#LyX 2.2 created this file. For more info see http://www.lyx.org/ \lyxformat 508 \begin_document \begin_header \save_transient_properties true \origin unavailable \textclass docbook-book \begin_preamble \end_preamble \use_default_options false \maintain_unincluded_children false \language english \language_package default \inputencoding default \fontencoding global \font_roman "default" "default" \font_sans "default" "default" \font_typewriter "default" "default" \font_math "auto" "auto" \font_default_family default \use_non_tex_fonts false \font_sc false \font_osf false \font_sf_scale 100 100 \font_tt_scale 100 100 \graphics default \default_output_format default \output_sync 0 \bibtex_command default \index_command default \paperfontsize default \spacing single \use_hyperref false \papersize default \use_geometry false \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 0 \use_package esint 0 \use_package mathdots 1 \use_package mathtools 0 \use_package mhchem 1 \use_package stackrel 0 \use_package stmaryrd 0 \use_package undertilde 0 \cite_engine basic \cite_engine_type default \biblio_style plain \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \justification true \use_refstyle 0 \index Index \shortcut idx \color #008000 \end_index \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \quotes_language swedish \papercolumns 1 \papersides 1 \paperpagestyle default \tracking_changes false \output_changes false \html_math_output 0 \html_css_as_file 0 \html_be_strict false \end_header \begin_body \begin_layout Title Linux IPv6 HOWTO (en) \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout PeterBieringerpb at bieringer dot de \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.67wip 2016-12-15 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.66 2014-05-15 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.65 2009-12-13 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.64 2009-06-11 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.60 2007-05-31 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout 0.51 2006-11-08 PB \end_layout \end_inset \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout \end_layout \end_inset \end_layout \begin_layout Abstract The goal of the Linux IPv6 HOWTO is to answer both basic and advanced questions about IPv6 on the Linux operating system. This HOWTO will provide the reader with enough information to install, configure, and use IPv6 applications on Linux machines. Intermediate releases of this HOWTO are available at \begin_inset CommandInset href LatexCommand href name "mirrors.bieringer.de" target "http://mirrors.bieringer.de/Linux+IPv6-HOWTO/" \end_inset or \begin_inset CommandInset href LatexCommand href name "mirrors.deepspace6.net" target "http://mirrors.deepspace6.net/Linux+IPv6-HOWTO/" \end_inset . See also \begin_inset CommandInset ref LatexCommand ref name "revision history" reference "revision-history" \end_inset for changes. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-general" \end_inset General \end_layout \begin_layout Standard Information about available translations you will find in section \begin_inset CommandInset ref LatexCommand ref name "Translations" reference "general-translations" \end_inset . \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "general-copright" \end_inset Copyright, license and others \end_layout \begin_layout Subsection Copyright \end_layout \begin_layout Standard Written and Copyright (C) 2001-2014 by Peter Bieringer \end_layout \begin_layout Subsection License \end_layout \begin_layout Standard \series bold This Linux IPv6 HOWTO is published under GNU GPL version 2 \series default : \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard The Linux IPv6 HOWTO, a guide how to configure and use IPv6 on Linux systems. \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard Copyright \lang ngerman © \lang english 2001-2014 Peter Bieringer \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard This documentation is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. \end_layout \begin_layout Standard This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. \end_layout \begin_layout Standard You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA. \end_layout \begin_layout Subsection About the author \end_layout \begin_layout Subsubsection Internet/IPv6 history of the author \end_layout \begin_layout Itemize 1993: I got in contact with the Internet using console based e-mail and news client (e.g. look for \begin_inset Quotes sld \end_inset e91abier \begin_inset Quotes srd \end_inset on \begin_inset CommandInset href LatexCommand href name "groups.google.com" target "http://groups.google.com/" \end_inset , that's me). \end_layout \begin_layout Itemize 1996: I got a request for designing a course on IPv6, including a workshop with the Linux operating system. \end_layout \begin_layout Itemize 1997: Started writing a guide on how to install, configure and use IPv6 on Linux systems, called \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset (see \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo/History" target "http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO-0.html#history" \end_inset for more information). \end_layout \begin_layout Itemize 2001: Started writing this new Linux IPv6 HOWTO. \end_layout \begin_layout Subsubsection Contact \end_layout \begin_layout Standard The author can be contacted via e-mail at and also via his \begin_inset CommandInset href LatexCommand href name "homepage" target "http://www.bieringer.de/pb/" \end_inset . \end_layout \begin_layout Standard He's currently living in Munich / Bavaria / Germany / Europe / Earth. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "general-category" \end_inset Category \end_layout \begin_layout Standard This HOWTO should be listed in category \begin_inset Quotes sld \end_inset \emph on Networking \emph default / \emph on Protocols \emph default \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Section Version, History and To-Do \end_layout \begin_layout Subsection Version \end_layout \begin_layout Standard The current version is shown at the beginning of the document. \end_layout \begin_layout Standard For other available versions/translations see also \begin_inset CommandInset href LatexCommand href name "http://www.bieringer.de/linux/IPv6/" target "http://www.bieringer.de/linux/IPv6/" \end_inset . \end_layout \begin_layout Subsection History \end_layout \begin_layout Subsubsection Major history \end_layout \begin_layout Standard 2001-11-30: Starting to design new HOWTO. \end_layout \begin_layout Standard 2002-01-02: A lot of content completed, first public release of chapter 1 (version 0.10). \end_layout \begin_layout Standard 2002-01-14: More completed, some reviews, public release of the whole document (version 0.14). \end_layout \begin_layout Standard 2002-08-16: Polish translation is in progress \end_layout \begin_layout Standard 2002-10-31: Chinese translation is available (see \begin_inset CommandInset ref LatexCommand ref name "Translations" reference "general-translations" \end_inset for more) \end_layout \begin_layout Standard 2002-11-10: German translation is in progress \end_layout \begin_layout Standard 2003-02-10: German translation is available \end_layout \begin_layout Standard 2003-04-09: French translation is in progress \end_layout \begin_layout Standard 2003-05-09: French translation is available \end_layout \begin_layout Standard 2003-10-16: Italian translation is in progress \end_layout \begin_layout Standard 2004-03-12: Italian translation is available \end_layout \begin_layout Standard 2004-06-18: Greek translation is in progress \end_layout \begin_layout Standard 2005-07-25: Turkish translation is availble \end_layout \begin_layout Standard 2007-03-28: Portuguese-Brazil translation is in progress \end_layout \begin_layout Standard 2008-07-30: Spanish translation is available (but still in progress) \end_layout \begin_layout Standard 2011-05-09: Portuguese-Brazil translation is again in progress \end_layout \begin_layout Subsubsection Full history \end_layout \begin_layout Standard See \begin_inset CommandInset ref LatexCommand ref name "revision history" reference "revision-history" \end_inset at the end of this document. \end_layout \begin_layout Subsection To-Do \end_layout \begin_layout Itemize Fill in missing content \end_layout \begin_layout Itemize Finishing grammar checking \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "general-translations" \end_inset Translations \end_layout \begin_layout Standard Translations always have to contain the URL, version number and copyright of the original document (but yours, too). Pls. don't translate the original changelog, this is not very useful - also do not translate the full section about available translations, can be run out-of-date, add an URL to this section here in the English howto. \end_layout \begin_layout Standard Looks like the document's change frequency is mostly less than once per month. Since version 0.27 it looks like that most of the content contributed by me has been written. Translations always have to use the English version as source. \end_layout \begin_layout Subsection To language \end_layout \begin_layout Standard Note: an overview with URLs can be found at \begin_inset CommandInset href LatexCommand href name "http://www.bieringer.de/linux/IPv6/" target "http://www.bieringer.de/linux/IPv6/" \end_inset . \end_layout \begin_layout Subsubsection Chinese \end_layout \begin_layout Standard A Chinese translation by Burma Chen (announced to me at 2002-10-31) can be found on the TLDP: \begin_inset CommandInset href LatexCommand href name "http://www.ibiblio.org/pub/Linux/docs/HOWTO/translations/zh/Linux-IPv6-HOWTO.txt.gz (g'zipped txt)" target "http://www.ibiblio.org/pub/Linux/docs/HOWTO/translations/zh/Linux-IPv6-HOWTO.txt.gz" \end_inset . It's a snapshot translation, don't know whether kept up-to-date. \end_layout \begin_layout Subsubsection Polish \end_layout \begin_layout Standard Since 2002-08-16 a Polish translation was started and is still in progress by Lukasz Jokiel . Taken source: CVS-version 1.29 of LyX file, which was source for howto version 0.27. Status is still work-in-progress (2004-08-30). \end_layout \begin_layout Subsubsection German \end_layout \begin_layout Standard With 2002-11-10 a German translation was started by Georg Käfer and the first public version was published 2003-02-10. It's originally available on Deep Space 6 at \begin_inset CommandInset href LatexCommand href name "http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-de/" target "http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-de/" \end_inset (mirrored e.g. on \begin_inset CommandInset href LatexCommand href name "http://mirrors.bieringer.de/Linux+IPv6-HOWTO-de/" target "http://mirrors.bieringer.de/Linux+IPv6-HOWTO-de/" \end_inset ). This version will stay up-to-date as much as possible. \end_layout \begin_layout Subsubsection French \end_layout \begin_layout Standard With 2003-04-09 a French translation was started by Michel Boucey and the first public version was published 2003-05-09. It's originally available on Deep Space 6 at \begin_inset CommandInset href LatexCommand href name "http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-fr/" target "http://mirrors.deepspace6.net/Linux+IPv6-HOWTO-fr/" \end_inset (mirrored e.g. on \begin_inset CommandInset href LatexCommand href name "http://mirrors.bieringer.de/Linux+IPv6-HOWTO-fr/" target "http://mirrors.bieringer.de/Linux+IPv6-HOWTO-fr/" \end_inset ). \end_layout \begin_layout Subsubsection Spanish \end_layout \begin_layout Standard A member of the MontevideoLibre, a project in Uruguay (South America) started the translation into Spanish in wiki format some time ago, but the URL is no longer available. \end_layout \begin_layout Subsubsection Italian \end_layout \begin_layout Standard With 2003-10-16 a Italian translation was started by Michele Ferritto for the \begin_inset CommandInset href LatexCommand href name "ILDP" target "http://ildp.pluto.linux.it/" \end_inset (Italian Linux Documentation Project) and the first public version was published 2004-03-12. It's originally available on the ILDP at \begin_inset CommandInset href LatexCommand href name "http://it.tldp.org/HOWTO/Linux+IPv6-HOWTO/" target "http://it.tldp.org/HOWTO/Linux+IPv6-HOWTO/" \end_inset . \end_layout \begin_layout Subsubsection Japanese \end_layout \begin_layout Standard On 2003-05-14 Shino Taketani send me a note that he planned to translate the HowTo into Japanese. \end_layout \begin_layout Subsubsection Greek \end_layout \begin_layout Standard On 2004-06-18 Nikolaos Tsarmpopoulos send me a note that he planned to translate the HowTo into Greek. \end_layout \begin_layout Subsubsection Turkish \end_layout \begin_layout Standard On 2005-07-18 Necdet Yucel send me a note that a Turkish translation is available. It's a snapshot translation (currently of 0.61) and can be found at \begin_inset CommandInset href LatexCommand href name "http://docs.comu.edu.tr/howto/ipv6-howto.html" target "http://docs.comu.edu.tr/howto/ipv6-howto.html" \end_inset . \end_layout \begin_layout Subsubsection Portuguese-Brazil \end_layout \begin_layout Standard On 2011-05-06 Gustavo Mendes de Carvalho start to translate the HowTo in Portuguese-Brazil. The first try in 2007 by Claudemir da Luz was never finished. \end_layout \begin_layout Section Technical \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "general-original-source" \end_inset Original source of this HOWTO \end_layout \begin_layout Standard This HOWTO is currently written with LyX version 1.6.1 on a Fedora 10 Linux system with template SGML/XML (DocBook book). It's available on \begin_inset CommandInset href LatexCommand href name "github / tLDP / LDP / users / Peter-Bieringer" target "https://github.com/tLDP/LDP/tree/master/LDP/users/Peter-Bieringer/" \end_inset for contribution. \end_layout \begin_layout Subsubsection Code line wrapping \end_layout \begin_layout Standard Code line wrapping is done using selfmade utility \begin_inset Quotes sld \end_inset lyxcodelinewrapper.pl \begin_inset Quotes srd \end_inset , you can get it from CVS for your own usage: \begin_inset CommandInset href LatexCommand href name "TLDP-CVS / users / Peter-Bieringer" target "http://cvs.tldp.org/go.to/LDP/LDP/users/Peter-Bieringer/" \end_inset \end_layout \begin_layout Subsubsection SGML generation \end_layout \begin_layout Standard SGML/XML is generated using export function in LyX. \end_layout \begin_layout Subsection On-line references to the HTML version of this HOWTO (linking/anchors) \end_layout \begin_layout Subsubsection Master index page \end_layout \begin_layout Standard Generally, a reference to the master index page is recommended. \end_layout \begin_layout Subsubsection Dedicated pages \end_layout \begin_layout Standard Because the HTML pages are generated out of the SGML file, the HTML filenames turn out to be quite random. However, some pages are tagged in LyX, resulting in static names. These tags are useful for references and shouldn't be changed in the future. \end_layout \begin_layout Standard If you think that I have forgotten a tag, please let me know, and I will add it. \end_layout \begin_layout Section Preface \end_layout \begin_layout Standard Some things first: \end_layout \begin_layout Subsection How many versions of a Linux & IPv6 related HOWTO are floating around? \end_layout \begin_layout Standard Including this, there are three (3) HOWTO documents available. Apologies, if that is too many ;-) \end_layout \begin_layout Subsubsection Linux IPv6 FAQ/HOWTO (outdated) \end_layout \begin_layout Standard The first IPv6 related document was written by \emph on Eric Osborne \emph default and called \begin_inset CommandInset href LatexCommand href name "Linux IPv6 FAQ/HOWTO" target "http://www.linuxhq.com/IPv6/" \end_inset (please use it only for historical issues). \series bold Latest \series default \series bold version \series default was 3.2.1 released July, 14 \series bold 1997 \series default . \end_layout \begin_layout Standard Please help: if someone knows the date of birth of this HOWTO, please send me an e-mail (information will be needed in \begin_inset Quotes sld \end_inset history \begin_inset Quotes srd \end_inset ). \end_layout \begin_layout Subsubsection IPv6 & Linux - HowTo (maintained) \end_layout \begin_layout Standard There exists a second version called \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset written by me ( \emph on Peter Bieringer \emph default ) in pure HTML. \series bold It was born \series default April \series bold 1997 \series default and the first English version was published in June 1997. I will continue to \series bold maintain \series default it, but it will slowly fade (but not full) in favour of the Linux IPv6 HOWTO you are currently reading. \end_layout \begin_layout Subsubsection Linux IPv6 HOWTO (this document) \end_layout \begin_layout Standard Because the \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset is written in pure HTML it's not really compatible with the \begin_inset CommandInset href LatexCommand href name "The Linux Documentation Project (TLDP)" target "http://www.tldp.org/" \end_inset . I ( \emph on Peter Bieringer \emph default ) got a request in late November 2001 to rewrite the \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset in SGML. However, because of the discontinuation of that HOWTO ( \begin_inset CommandInset href LatexCommand href name "Future of IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO-0.html#history" \end_inset ), and as IPv6 is becoming more and more standard, I decided to write a new document covering basic and advanced issues which will remain important over the next few years. More dynamic and some advanced content will be still found further on in the second HOWTO ( \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset ). \end_layout \begin_layout Section Used terms, glossary and shortcuts \end_layout \begin_layout Subsection Network related \end_layout \begin_layout Description Base \begin_inset space ~ \end_inset 10 Well known decimal number system, represent any value with digit 0-9. \end_layout \begin_layout Description Base \begin_inset space ~ \end_inset 16 Usually used in lower and higher programming languages, known also as hexadecimal number system, represent any value with digit 0-9 and char A-F (case insensitive). \end_layout \begin_layout Description Base \begin_inset space ~ \end_inset 85 Representation of a value with 85 different digits/chars, this can lead to shorter strings but never seen in the wild. \end_layout \begin_layout Description Bit Smallest storage unit, on/true (1) or off/false (0) \end_layout \begin_layout Description Byte Mostly a collection of 8 (but not really a must - see older computer systems) bits \end_layout \begin_layout Description Device Here, hardware of network connection, see also NIC \end_layout \begin_layout Description Dual \begin_inset space ~ \end_inset homed \begin_inset space ~ \end_inset host A dual homed host is a node with two network (physical or virtual) interfaces on two different links, but does not forward any packets between the interfaces. \end_layout \begin_layout Description Host Generally a single homed host on a link. Normally it has only one active network interface, e.g. Ethernet or (not and) PPP. \end_layout \begin_layout Description Interface Mostly same as \begin_inset Quotes sld \end_inset device \begin_inset Quotes srd \end_inset , see also NIC \end_layout \begin_layout Description IP \begin_inset space ~ \end_inset Header Header of an IP packet (each network packet has a header, kind of is depending on network layer) \end_layout \begin_layout Description Link A link is a layer 2 network packet transport medium, examples are Ethernet, Token Ring, PPP, SLIP, ATM, ISDN, Frame Relay,... \end_layout \begin_layout Description Node A node is a host or a router. \end_layout \begin_layout Description Octet A collection of 8 real bits, today also similar to \begin_inset Quotes sld \end_inset byte \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Description Port Information for the TCP/UDP dispatcher (layer 4) to transport information to upper layers \end_layout \begin_layout Description Protocol Each network layer contains mostly a protocol field to make life easier on dispatching transported information to upper layer, seen in layer 2 (MAC) and 3 (IP) \end_layout \begin_layout Description Router A router is a node with two or more network (physical or virtual) interfaces, capable of forwarding packets between the interfaces. \end_layout \begin_layout Description Socket An IP socket is defined by source and destination IP addresses and Ports and (binding) \end_layout \begin_layout Description Stack Network related a collection of layers \end_layout \begin_layout Description Subnetmask IP networks uses bit masks to separate local networks from remote ones \end_layout \begin_layout Description Tunnel A tunnel is typically a point-to-point connection over which packets are exchanged which carry the data of another protocol, e.g. an IPv6-in-IPv4 tunnel. \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "Glossar" \end_inset Shortcuts \end_layout \begin_layout Description ACL Access Control List \end_layout \begin_layout Description API Application Programming Interface \end_layout \begin_layout Description ASIC Application Specified Integrated Circuit \end_layout \begin_layout Description BSD Berkeley Software Distribution \end_layout \begin_layout Description CAN-Bus Controller Area Network Bus (physical bus system) \end_layout \begin_layout Description ISP Internet Service Provider \end_layout \begin_layout Description KAME Project - a joint effort of six companies in Japan to provide a free IPv6 and IPsec (for both IPv4 and IPv6) stack for BSD variants to the world \begin_inset CommandInset href LatexCommand href name "www.kame.net" target "http://www.kame.net/" \end_inset \end_layout \begin_layout Description LIR Local Internet Registry \end_layout \begin_layout Description NIC Network Interface Card \end_layout \begin_layout Description RFC Request For Comments - set of technical and organizational notes about the Internet \end_layout \begin_layout Description USAGI UniverSAl playGround for Ipv6 Project - works to deliver the production quality IPv6 protocol stack for the Linux system. \end_layout \begin_layout Subsection Document related \end_layout \begin_layout Subsubsection Long code line wrapping signal char \end_layout \begin_layout Standard The special character \begin_inset Quotes sld \end_inset ¬ \begin_inset Quotes srd \end_inset is used for signaling that this code line is wrapped for better viewing in PDF and PS files. \end_layout \begin_layout Subsubsection Placeholders \end_layout \begin_layout Standard In generic examples you will sometimes find the following: \end_layout \begin_layout Code \end_layout \begin_layout Standard For real use on your system command line or in scripts this has to be replaced with relevant content (removing the < and > of course), the result would be e.g. \end_layout \begin_layout Code 1.2.3.4 \end_layout \begin_layout Subsubsection Commands in the shell \end_layout \begin_layout Standard Commands executable as non-root user begin with $, e.g. \end_layout \begin_layout Code $ whoami \end_layout \begin_layout Standard Commands executable as root user begin with #, e.g. \end_layout \begin_layout Code # whoami \end_layout \begin_layout Section Requirements for using this HOWTO \end_layout \begin_layout Subsection Personal prerequisites \end_layout \begin_layout Subsubsection Experience with Unix tools \end_layout \begin_layout Standard You should be familiar with the major Unix tools e.g. \emph on grep \emph default , \emph on awk \emph default , \emph on find \emph default , ... , and know about their most commonly used command-line options. \end_layout \begin_layout Subsubsection Experience with networking theory \end_layout \begin_layout Standard You should know about layers, protocols, addresses, cables, plugs, etc. If you are new to this field, here is one good starting point for you: \lang ngerman \begin_inset CommandInset href LatexCommand href name "http://www.rigacci.org/docs/biblio/online/intro_to_networking/book1.htm" target "http://www.rigacci.org/docs/biblio/online/intro_to_networking/book1.htm" \end_inset \end_layout \begin_layout Subsubsection Experience with IPv4 configuration \end_layout \begin_layout Standard You should definitely have some experience in IPv4 configuration, otherwise it will be hard for you to understand what is really going on. \end_layout \begin_layout Subsubsection Experience with the Domain Name System (DNS) \end_layout \begin_layout Standard Also you should understand what the Domain Name System (DNS) is, what it provides and how to use it. \end_layout \begin_layout Subsubsection Experience with network debugging strategies \end_layout \begin_layout Standard You should at least understand how to use \emph on tcpdump \emph default and what \emph on \emph default it can show you. Otherwise, network debugging will very difficult for you. \end_layout \begin_layout Subsection Linux operating system compatible hardware \end_layout \begin_layout Standard Surely you wish to experiment with real hardware, and not only read this HOWTO to fall asleep here and there. ;-7) \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-basics" \end_inset Basics \end_layout \begin_layout Section What is IPv6? \end_layout \begin_layout Standard IPv6 is a new layer 3 protocol \color none which will supersede IPv4 (also known as IP). IPv4 was designed a long time ago ( \begin_inset CommandInset href LatexCommand href name "RFC 760 / Internet Protocol" target "http://www.faqs.org/rfcs/rfc760.html" \end_inset from January 1980) and since its inception, there have been many requests for more addresses and enhanced capabilities. Latest RFC is \begin_inset CommandInset href LatexCommand href name "RFC 2460 / Internet Protocol Version 6 Specification" target "http://www.faqs.org/rfcs/rfc2460.html" \end_inset . Major changes in IPv6 are the redesign of the header, including the increase of address size from 32 bits to 128 bits. Because layer 3 is responsible for end-to-end packet transport using packet routing based on addresses, it must include the new IPv6 addresses (source and destination), like IPv4. \end_layout \begin_layout Standard For more information about the IPv6 history take a look at older IPv6 related RFCs listed e.g. at \begin_inset CommandInset href LatexCommand href name "SWITCH IPv6 Pilot / References" target "http://www.switch.ch/lan/ipv6/references.html" \end_inset . \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "basic-history-IPv6-Linux" \end_inset History of IPv6 in Linux \end_layout \begin_layout Standard The years 1992, 1993 and 1994 of the IPv6 History (in general) are covered by the following document: \begin_inset CommandInset href LatexCommand href name "IPv6 or IPng (IP next generation)" target "http://www.laynetworks.com/IPv6.htm#CH3" \end_inset . \end_layout \begin_layout Standard To-do: better time-line, more content... \end_layout \begin_layout Subsection Beginning \end_layout \begin_layout Standard The first IPv6 related network code was added to the Linux kernel 2.1.8 in November 1996 by Pedro Roque. It was based on the BSD API: \end_layout \begin_layout Code diff -u --recursive --new-file v2.1.7/linux/include/linux/in6.h \end_layout \begin_layout Code ¬ linux/include/linux/in6.h \end_layout \begin_layout Code --- v2.1.7/linux/include/linux/in6.h Thu Jan 1 02:00:00 1970 \end_layout \begin_layout Code +++ linux/include/linux/in6.h Sun Nov 3 11:04:42 1996 \end_layout \begin_layout Code @@ -0,0 +1,99 @@ \end_layout \begin_layout Code +/* \end_layout \begin_layout Code + * Types and definitions for AF_INET6 \end_layout \begin_layout Code + * Linux INET6 implementation \end_layout \begin_layout Code + * + * Authors: \end_layout \begin_layout Code + * Pedro Roque <******> \end_layout \begin_layout Code + * \end_layout \begin_layout Code + * Source: \end_layout \begin_layout Code + * IPv6 Program Interfaces for BSD Systems \end_layout \begin_layout Code + * \end_layout \begin_layout Standard The shown lines were copied from patch-2.1.8 (e-mail address was blanked on copy&paste). \end_layout \begin_layout Subsection In between \end_layout \begin_layout Standard Because of lack of manpower, the IPv6 implementation in the kernel was unable to follow the discussed drafts or newly released RFCs. In October 2000, a project was started in Japan, called \begin_inset CommandInset href LatexCommand href name "USAGI" target "http://www.linux-ipv6.org/" \end_inset , whose aim was to implement all missing, or outdated IPv6 support in Linux. It tracks the current IPv6 implementation in FreeBSD made by the \begin_inset CommandInset href LatexCommand href name "KAME project" target "http://www.kame.net/" \end_inset . From time to time they create snapshots against current vanilla Linux kernel sources. \end_layout \begin_layout Standard Until kernel development series 2.5.x was started, the \begin_inset CommandInset href LatexCommand href name "USAGI" target "http://www.linux-ipv6.org/" \end_inset patch was so big, that Linux networking maintainers were unable to include it completly in the production source of the Linux kernel 2.4.x series. \end_layout \begin_layout Standard During kernel development series 2.5.x, \begin_inset CommandInset href LatexCommand href name "USAGI" target "http://www.linux-ipv6.org/" \end_inset tried to insert all of their current extensions into this. \end_layout \begin_layout Subsection Current \end_layout \begin_layout Standard Many of the long-term developed IPv6 related patches by \begin_inset CommandInset href LatexCommand href name "USAGI" target "http://www.linux-ipv6.org/" \end_inset and others are integrated into vanilla kernel series 2.6.x. \end_layout \begin_layout Subsection Future \end_layout \begin_layout Standard \begin_inset CommandInset href LatexCommand href name "USAGI" target "http://www.linux-ipv6.org/" \end_inset and others are still working on implementation of newer features like mobililty and others. From time to time, new extension patches are released and also integration into vanilla kernel series is made. \end_layout \begin_layout Section What do IPv6 addresses look like? \end_layout \begin_layout Standard \align left As previously mentioned, IPv6 addresses are 128 bits long. This number of bits generates very high decimal numbers with up to 39 digits: \end_layout \begin_layout Code 2^128-1: 340282366920938463463374607431768211455 \end_layout \begin_layout Standard \align left Such numbers are not really addresses that can be memorized. Also the IPv6 address schema is bitwise oriented (just like IPv4, but that's not often recognized). Therefore a better notation of such big numbers is hexadecimal. In hexadecimal, 4 bits (also known as \begin_inset Quotes sld \end_inset nibble \begin_inset Quotes srd \end_inset ) are represented by a digit or character from 0-9 and a-f (10-15). This format reduces the length of the IPv6 address to 32 characters. \end_layout \begin_layout Code 2^128-1: 0xffffffffffffffffffffffffffffffff \end_layout \begin_layout Standard \align left This representation is still not very convenient (possible mix-up or loss of single hexadecimal digits), so the designers of IPv6 chose a hexadecimal format with a colon as separator after each block of 16 bits. In addition, the leading " \family typewriter 0x \family default " (a signifier for hexadecimal values used in programming languages) is removed: \end_layout \begin_layout Code 2^128-1: ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff \end_layout \begin_layout Standard \align left A usable address (see address types later) is e.g.: \end_layout \begin_layout Code 2001:0db8:0100:f101:0210:a4ff:fee3:9566 \end_layout \begin_layout Standard \align left For simplifications, leading zeros of each 16 bit block can be omitted: \end_layout \begin_layout Code 2001:0db8:0100:f101:0210:a4ff:fee3:9566 -> \end_layout \begin_layout Code ¬ 2001:db8:100:f101:210:a4ff:fee3:9566 \end_layout \begin_layout Standard \align left One sequence of 16 bit blocks containing only zeroes can be replaced with \begin_inset Quotes eld \end_inset \family typewriter :: \family default \begin_inset Quotes eld \end_inset . But not more than one at a time, otherwise it is no longer a unique representat ion. \end_layout \begin_layout Code 2001:0db8:100:f101:0:0:0:1 -> 2001:db8:100:f101::1 \end_layout \begin_layout Standard \align left The biggest reduction is seen by the IPv6 localhost address: \end_layout \begin_layout Code 0000:0000:0000:0000:0000:0000:0000:0001 -> ::1 \end_layout \begin_layout Standard \align left There is also a so-called \emph on compact \emph default (base85 coded) representation defined in \begin_inset CommandInset href LatexCommand href name "RFC 1924 / A Compact Representation of IPv6 Addresses" target "http://www.faqs.org/rfcs/rfc1924.html" \end_inset (published on 1. April 1996), never seen in the wild, probably an April fool's joke, but here is an example: \end_layout \begin_layout Code # ipv6calc --addr_to_base85 2001:0db8:0100:f101:0210:a4ff:fee3:9566 \end_layout \begin_layout Code 9R}vSQZ1W=9A_Q74Lz&R \end_layout \begin_layout Quotation Info: \emph on ipv6calc \emph default is an IPv6 address format calculator and converter program and can be found here: \lang ngerman \begin_inset CommandInset href LatexCommand href name "ipv6calc homepage" target "http://www.deepspace6.net/projects/ipv6calc.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/projects/ipv6calc.html" \end_inset ) \end_layout \begin_layout Section FAQ (Basics) \end_layout \begin_layout Subsection Why is the name IPv6 and not IPv5 as successor for IPv4? \end_layout \begin_layout Standard \align left On any IP header, the first 4 bits are reserved for protocol version. So theoretically a protocol number between 0 and 15 is possible: \end_layout \begin_layout Itemize \align left 4: is already used for IPv4 \end_layout \begin_layout Itemize \align left 5: is reserved for the Stream Protocol (STP, \begin_inset CommandInset href LatexCommand href name "RFC 1819 / Internet Stream Protocol Version 2" target "http://www.faqs.org/rfcs/rfc1819.html" \end_inset ) (which never really made it to the public) \end_layout \begin_layout Standard \align left The next free number was 6. Hence IPv6 was born! \end_layout \begin_layout Subsection IPv6 addresses: why such a high number of bits? \end_layout \begin_layout Standard \align left During the design of IPv4, people thought that 32 bits were enough for the world. Looking back into the past, 32 bits were enough until now and will perhaps be enough for another few years. However, 32 bits are not enough to provide each network device with a global address in the future. Think about mobile phones, cars (including electronic devices on its CAN-bus), toasters, refrigerators, light switches, and so on... \end_layout \begin_layout Standard \align left So designers have chosen 128 bits, 4 times more in length than in IPv4 today. \end_layout \begin_layout Standard The usable size is smaller than it may appear however. This is because in the currently defined address schema, 64 bits are used for interface identifiers. The other 64 bits are used for routing. Assuming the current strict levels of aggregation (/48, /32, ...), it is still possible to \begin_inset Quotes sld \end_inset run out \begin_inset Quotes srd \end_inset of space, but hopefully not in the near future. \end_layout \begin_layout Standard See also for more information \begin_inset CommandInset href LatexCommand href name "RFC 1715 / The H Ratio for Address Assignment Efficiency" target "http://www.faqs.org/rfcs/rfc1715.html" \end_inset and \begin_inset CommandInset href LatexCommand href name "RFC 3194 / The Host-Density Ratio for Address Assignment Efficiency" target "http://www.faqs.org/rfcs/rfc3194.html" \end_inset . \end_layout \begin_layout Subsection IPv6 addresses: why so small a number of bits on a new design? \end_layout \begin_layout Standard \align left While, there are (possibly) some people (only know about Jim Fleming...) on the Internet who are thinking about IPv8 and IPv16, their design is far away from acceptance and implementation. In the meantime 128 bits was the best choice regarding header overhead and data transport. Consider the minimum Maximum Transfer Unit (MTU) in IPv4 (576 octets) and in IPv6 (1280 octets), the header length in IPv4 is 20 octets (minimum, can increase to 60 octets with IPv4 options) and in IPv6 is 40 octets (fixed). This is 3.4 % of minimum MTU in IPv4 and 3.1 % of minimum MTU in IPv6. This means the header overhead is almost equal. More bits for addresses would require bigger headers and therefore more overhead. Also, consider the maximum MTU on normal links (like Ethernet today): it's 1500 octets (in special cases: 9k octets using Jumbo frames). Ultimately, it wouldn't be a proper design if 10 % or 20 % of transported data in a Layer-3 packet were used for addresses and not for payload. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-addresstypes" \end_inset Address types \end_layout \begin_layout Standard Like IPv4, IPv6 addresses can be split into network and host parts using subnet masks. \end_layout \begin_layout Standard IPv4 has shown that sometimes it would be nice, if more than one IP address can be assigned to an interface, each for a different purpose (aliases, multi-cast). To remain extensible in the future, IPv6 is going further and allows more than one IPv6 address to be assigned to an interface. There is currently no limit defined by an RFC, only in the implementation of the IPv6 stack (to prevent DoS attacks). \end_layout \begin_layout Standard Using this large number of bits for addresses, IPv6 defines address types based on some leading bits, which are hopefully never going to be broken in the future (unlike IPv4 today and the history of class A, B, and C). \begin_inset Separator latexpar \end_inset \end_layout \begin_layout Standard \align left Also the number of bits are separated into a network part (upper 64 bits) and a host part (lower 64 bits), to facilitate auto-configuration. \end_layout \begin_layout Section Addresses without a special prefix \end_layout \begin_layout Subsection Localhost address \end_layout \begin_layout Standard This is a special address for the loopback interface, similiar to IPv4 with its \begin_inset Quotes sld \end_inset 127.0.0.1 \begin_inset Quotes srd \end_inset . With IPv6, the localhost address is: \end_layout \begin_layout Code 0000:0000:0000:0000:0000:0000:0000:0001 \end_layout \begin_layout Standard or compressed: \end_layout \begin_layout Code ::1 \end_layout \begin_layout Standard \align left Packets with this address as source or destination should never leave the sending host. \end_layout \begin_layout Subsection Unspecified address \end_layout \begin_layout Standard This is a special address like \begin_inset Quotes sld \end_inset any \begin_inset Quotes srd \end_inset or \begin_inset Quotes sld \end_inset 0.0.0.0 \begin_inset Quotes srd \end_inset in IPv4 . For IPv6 it's: \end_layout \begin_layout Code 0000:0000:0000:0000:0000:0000:0000:0000 \end_layout \begin_layout Standard or: \end_layout \begin_layout Code :: \end_layout \begin_layout Standard These addresses are mostly used/seen in socket binding (to any IPv6 address) or routing tables. \end_layout \begin_layout Standard Note: the unspecified address cannot be used as destination address. \end_layout \begin_layout Subsection IPv6 address with embedded IPv4 address \end_layout \begin_layout Standard There are two addresses which contain an IPv4 address. \end_layout \begin_layout Subsubsection IPv4-mapped IPv6 address \end_layout \begin_layout Standard IPv4-only IPv6-compatible addresses are sometimes used/shown for sockets created by an IPv6-enabled daemon, but only binding to an IPv4 address. \end_layout \begin_layout Standard These addresses are defined with a special prefix of length 96 (a.b.c.d is the IPv4 address): \end_layout \begin_layout Code 0:0:0:0:0:ffff:a.b.c.d/96 \end_layout \begin_layout Standard or in compressed format \end_layout \begin_layout Code ::ffff:a.b.c.d/96 \end_layout \begin_layout Standard For example, the IPv4 address 1.2.3.4 looks like this: \end_layout \begin_layout Code ::ffff:1.2.3.4 \end_layout \begin_layout Subsubsection IPv4-compatible IPv6 address \end_layout \begin_layout Standard IPv4-compatible IPv6 addresses are used for automatic tunneling ( \begin_inset CommandInset href LatexCommand href name "RFC 2893 / Transition Mechanisms for IPv6 Hosts and Routers" target "http://www.faqs.org/rfcs/rfc2893.html" \end_inset ), which is being replaced by \begin_inset CommandInset ref LatexCommand ref name "6to4 tunneling" reference "tunneling-6to4" \end_inset . \end_layout \begin_layout Code 0:0:0:0:0:0:a.b.c.d/96 \end_layout \begin_layout Standard or in compressed format \end_layout \begin_layout Code ::a.b.c.d/96 \end_layout \begin_layout Section Network part, also known as prefix \end_layout \begin_layout Standard Designers defined some address types and left a lot of scope for future definitions as currently unknown requirements arise. \begin_inset CommandInset href LatexCommand href name "RFC 4291 / IP Version 6 Addressing Architecture" target "http://www.faqs.org/rfcs/rfc4291.html" \end_inset defines the current addressing scheme. \begin_inset Separator latexpar \end_inset \end_layout \begin_layout Standard \align left Now lets take a look at the different types of prefixes (and therefore address types): \end_layout \begin_layout Subsection Link local address type \end_layout \begin_layout Standard \align left These are special addresses which will only be valid on a link of an interface. Using this address as destination the packet would never pass through a router. It's used for link communications such as: \end_layout \begin_layout Itemize \align left anyone else here on this link? \end_layout \begin_layout Itemize \align left anyone here with a special address (e.g. looking for a router)? \end_layout \begin_layout Standard \align left They begin with ( where \emph on \begin_inset Quotes sld \end_inset x \begin_inset Quotes srd \end_inset \emph default is any hex character, normally \emph on \begin_inset Quotes sld \end_inset 0 \emph default \begin_inset Quotes srd \end_inset ) \end_layout \begin_layout Code fe8x: <- currently the only one in use \end_layout \begin_layout Code fe9x: \end_layout \begin_layout Code feax: \end_layout \begin_layout Code febx: \end_layout \begin_layout Standard An address with this prefix is found on each IPv6-enabled interface after stateless auto-configuration (which is normally always the case). \end_layout \begin_layout Subsection Site local address type \end_layout \begin_layout Standard \align left These are addresses similar to the \begin_inset CommandInset href LatexCommand href name "RFC 1918 / Address Allocation for Private Internets" target "http://www.faqs.org/rfcs/rfc1918.html" \end_inset in IPv4 today, with the added advantage that everyone who use this address type has the capability to use the given 16 bits for a maximum number of 65536 subnets. Comparable with the \family typewriter 10.0.0.0/8 \family default in IPv4 today. \end_layout \begin_layout Standard \align left Another advantage: because it's possible to assign more than one address to an interface with IPv6, you can also assign such a site local address in addition to a global one. \end_layout \begin_layout Standard \align left It begins with: \end_layout \begin_layout Code fecx: <- most commonly used \end_layout \begin_layout Code fedx: \end_layout \begin_layout Code feex: \end_layout \begin_layout Code fefx: \end_layout \begin_layout Code \end_layout \begin_layout Standard (where \emph on \begin_inset Quotes sld \end_inset x \begin_inset Quotes srd \end_inset \emph default is any hex character, normally \emph on \begin_inset Quotes sld \end_inset 0 \emph default \begin_inset Quotes srd \end_inset ) \end_layout \begin_layout Standard This address type is now deprecated \begin_inset CommandInset href LatexCommand href name "RFC 3879 / Deprecating Site Local Addresses" target "http://www.faqs.org/rfcs/rfc3879.html" \end_inset , but for a test in a lab, such addresses are still a good choice in my humble opinion. \end_layout \begin_layout Subsection Unique Local IPv6 Unicast Addresses \end_layout \begin_layout Standard Because the original defined site local addresses are not unique, this can lead to major problems, if two former independend networks would be connected later (overlapping of subnets). This and other issues lead to a new address type named \begin_inset CommandInset href LatexCommand href name "RFC 4193 / Unique Local IPv6 Unicast Addresses" target "http://www.faqs.org/rfcs/rfc4193.html" \end_inset . \begin_inset Separator latexpar \end_inset \end_layout \begin_layout Standard \align left It begins with: \end_layout \begin_layout Code fcxx: \end_layout \begin_layout Code fdxx: <- currently the only one in use \end_layout \begin_layout Standard \align left A part of the prefix (40 bits) are generated using a pseudo-random algorithm and it's improbable, that two generated ones are equal. \end_layout \begin_layout Standard Example for a prefix (generated using a web-based tool: \begin_inset CommandInset href LatexCommand href name "Goebel Consult / createLULA" target "http://www.goebel-consult.de/ipv6/createLULA" \end_inset ): \end_layout \begin_layout Code fd0f:8b72:ac90::/48 \end_layout \begin_layout Subsection Global address type "(Aggregatable) global unicast" \end_layout \begin_layout Standard \align left Today, there is one global address type defined (the first design, called "provider based," was thrown away some years ago \begin_inset CommandInset href LatexCommand href name "RFC 1884 / IP Version 6 Addressing Architecture [obsolete]" target "http://www.faqs.org/rfcs/rfc1884.html" \end_inset , you will find some remains in older Linux kernel sources). \end_layout \begin_layout Standard \align left It begins with ( \emph on x \emph default are hex characters) \end_layout \begin_layout Code 2xxx: \end_layout \begin_layout Code 3xxx: \end_layout \begin_layout Standard Note: the prefix \begin_inset Quotes sld \end_inset aggregatable \begin_inset Quotes srd \end_inset is thrown away in current drafts. \begin_inset Newline newline \end_inset There are some further subtypes defined, see below: \end_layout \begin_layout Subsubsection 6bone test addresses \end_layout \begin_layout Standard \align left These were the first global addresses which were defined and in use. They all start with \end_layout \begin_layout Code 3ffe: \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code 3ffe:ffff:100:f102::1 \end_layout \begin_layout Standard A special 6bone test address which will never be globally unique begins with \end_layout \begin_layout Code 3ffe:ffff: \end_layout \begin_layout Standard and is mostly shown in older examples. The reason for this is, if real addresses are are shown, it's possible for someone to do a copy & paste to their configuration files, thus inadvertent ly causing duplicates on a globally unique address. This would cause serious problems for the original host (e.g. getting answer packets for request that were never sent). \begin_inset Newline newline \end_inset Because IPv6 is now in production, this prefix is no longer be delegated and is removed from routing after 6.6.2006 (see \begin_inset CommandInset href LatexCommand href name "RFC 3701 / 6bone Phaseout" target "http://www.faqs.org/rfcs/rfc3701.html" \end_inset for more). \end_layout \begin_layout Subsubsection 6to4 addresses \end_layout \begin_layout Standard \align left These addresses, designed for a special tunneling mechanism [ \begin_inset CommandInset href LatexCommand href name "RFC 3056 / Connection of IPv6 Domains via IPv4 Clouds" target "http://www.faqs.org/rfcs/rfc3056.html" \end_inset and \begin_inset CommandInset href LatexCommand href name "RFC 2893 / Transition Mechanisms for IPv6 Hosts and Routers" target "http://www.faqs.org/rfcs/rfc2893.html" \end_inset ], encode a given IPv4 address and a possible subnet and begin with \end_layout \begin_layout Code 2002: \end_layout \begin_layout Standard For example, representing 192.168.1.1/5: \end_layout \begin_layout Code 2002:c0a8:0101:5::1 \end_layout \begin_layout Standard A small shell command line can help you generating such address out of a given IPv4 one: \end_layout \begin_layout Code ipv4="1.2.3.4"; sla="5"; printf "2002:%02x%02x:%02x%02x:%04x::1" `echo $ipv4 \end_layout \begin_layout Code ¬ | tr "." " "` $sla \end_layout \begin_layout Standard See also \begin_inset CommandInset ref LatexCommand ref name "tunneling using 6to4" reference "tunneling-6to4" \end_inset and \begin_inset CommandInset ref LatexCommand ref name "information about 6to4 relay routers" reference "information-joinipv6-6to4-tunneling" \end_inset . \end_layout \begin_layout Subsubsection Assigned by provider for hierarchical routing \end_layout \begin_layout Standard These addresses are delegated to Internet service providers (ISP) and begin currently with \end_layout \begin_layout Code 2001: \end_layout \begin_layout Standard Prefixes to major (backbone owning) ISPs (also known as LIRs) are delegated by \begin_inset CommandInset ref LatexCommand ref name "local registries" reference "information-majorregionregistries" \end_inset and currently have a prefix with length 32 assigned. \end_layout \begin_layout Standard Any ISP customer can get a prefix with length 48. \end_layout \begin_layout Subsubsection Addresses reserved for examples and documentation \end_layout \begin_layout Standard Currently, two address ranges are reserved for examples and documentation \begin_inset CommandInset href LatexCommand href name "RFC 3849 / IPv6 Address Prefix Reserved for Documentation" target "http://www.faqs.org/rfcs/rfc3849.html" \end_inset : \end_layout \begin_layout Code 3fff:ffff::/32 \end_layout \begin_layout Code 2001:0DB8::/32 EXAMPLENET-WF \end_layout \begin_layout Standard These address ranges should be filtered based on source addresses and should NOT be routed on border routers to the internet, if possible. \end_layout \begin_layout Subsection Multicast addresses \end_layout \begin_layout Standard \align left Multicast addresses are used for related services. \end_layout \begin_layout Standard \align left They alway start with ( \emph on xx \emph default is the scope value) \end_layout \begin_layout Code ffxy: \end_layout \begin_layout Standard They are split into scopes and types: \end_layout \begin_layout Subsubsection Multicast scopes \end_layout \begin_layout Standard Multicast scope is a parameter to specify the maximum distance a multicast packet can travel from the sending entity. \end_layout \begin_layout Standard Currently, the following regions (scopes) are defined: \end_layout \begin_layout Itemize ffx1: node-local, packets never leave the node. \end_layout \begin_layout Itemize ffx2: link-local, packets are never forwarded by routers, so they never leave the specified link. \end_layout \begin_layout Itemize ffx5: site-local, packets never leave the site. \end_layout \begin_layout Itemize ffx8: organization-local, packets never leave the organization (not so easy to implement, must be covered by routing protocol). \end_layout \begin_layout Itemize ffxe: global scope. \end_layout \begin_layout Itemize others are reserved \end_layout \begin_layout Subsubsection Multicast types \end_layout \begin_layout Standard There are many types already defined/reserved (see \begin_inset CommandInset href LatexCommand href name "RFC 4291 / IP Version 6 Addressing Architecture" target "http://www.faqs.org/rfcs/rfc4291.html" \end_inset for details). Some examples are: \end_layout \begin_layout Itemize All Nodes Address: ID = 1h, addresses all hosts on the local node (ff01:0:0:0:0: 0:0:1) or the connected link (ff02:0:0:0:0:0:0:1). \end_layout \begin_layout Itemize All Routers Address: ID = 2h, addresses all routers on the local node (ff01:0:0: 0:0:0:0:2), on the connected link (ff02:0:0:0:0:0:0:2), or on the local site (ff05:0:0:0:0:0:0:2) \end_layout \begin_layout Subsubsection Solicited node link-local multicast address \end_layout \begin_layout Standard Special multicast address used as destination address in neighborhood discovery, because unlike in IPv4, ARP no longer exists in IPv6. \end_layout \begin_layout Standard An example of this address looks like \end_layout \begin_layout Code ff02::1:ff00:1234 \end_layout \begin_layout Standard Used prefix shows that this is a link-local multicast address. The suffix is generated from the destination address. In this example, a packet should be sent to address \begin_inset Quotes eld \end_inset fe80::1234 \begin_inset Quotes erd \end_inset , but the network stack doesn't know the current layer 2 MAC address. It replaces the upper 104 bits with \begin_inset Quotes eld \end_inset ff02:0:0:0:0:1:ff00::/104 \begin_inset Quotes erd \end_inset and leaves the lower 24 bits untouched. This address is now used `on-link' to find the corresponding node which has to send a reply containing its layer 2 MAC address. \end_layout \begin_layout Subsection Anycast addresses \end_layout \begin_layout Standard Anycast addresses are special addresses and are used to cover things like nearest DNS server, nearest DHCP server, or similar dynamic groups. Addresses are taken out of the unicast address space (aggregatable global or site-local at the moment). The anycast mechanism (client view) will be handled by dynamic routing protocols. \end_layout \begin_layout Standard Note: Anycast addresses cannot be used as source addresses, they are only used as destination addresses. \end_layout \begin_layout Subsubsection Subnet-router anycast address \end_layout \begin_layout Standard A simple example for an anycast address is the subnet-router anycast address. Assuming that a node has the following global assigned IPv6 address: \end_layout \begin_layout Code 2001:db8:100:f101:210:a4ff:fee3:9566/64 <- Node's address \end_layout \begin_layout Standard The subnet-router anycast address will be created blanking the suffix (least significant 64 bits) completely: \end_layout \begin_layout Code 2001:db8:100:f101::/64 <- subnet-router anycast address \end_layout \begin_layout Section Address types (host part) \end_layout \begin_layout Standard \align left For auto-configuration and mobility issues, it was decided to use the lower 64 bits as the host part of the address in most of the current address types. Therefore each single subnet can hold a large amount of addresses. \end_layout \begin_layout Standard \align left This host part can be inspected differently: \end_layout \begin_layout Subsection Automatically computed (also known as stateless) \end_layout \begin_layout Standard With auto-configuration, the host part of the address is computed by converting the MAC address of an interface (if available), with the EUI-64 method, to a unique IPv6 address. If no MAC address is available for this device (happens e.g. on virtual devices), something else (like the IPv4 address or the MAC address of a physical interface) is used instead. \end_layout \begin_layout Standard E.g. a NIC has following MAC address (48 bit): \end_layout \begin_layout Code 00:10:a4:01:23:45 \end_layout \begin_layout Standard \align left This would be expanded according to the \begin_inset CommandInset href LatexCommand href name "IEEE-Tutorial EUI-64" target "http://standards.ieee.org/regauth/oui/tutorials/EUI64.html" \end_inset design for EUI-48 identifiers to the 64 bit interface identifier: \end_layout \begin_layout Code 0210:a4ff:fe01:2345 \end_layout \begin_layout Standard \align left With a given prefix, the result is the IPv6 address shown in example above: \end_layout \begin_layout Code 2001:0db8:0100:f101:0210:a4ff:fe01:2345 \end_layout \begin_layout Subsubsection Privacy problem with automatically computed addresses and a solution \end_layout \begin_layout Standard \align left Because the "automatically computed" host part is globally unique (except when a vendor of a NIC uses the same MAC address on more than one NIC), client tracking is possible on the host when not using a proxy of any kind. \end_layout \begin_layout Standard \align left This is a known problem, and a solution was defined: privacy extension, defined in \begin_inset CommandInset href LatexCommand href name "RFC 3041 / Privacy Extensions for Stateless Address Autoconfiguration in IPv6" target "http://www.faqs.org/rfcs/rfc3041.html" \end_inset (there is also already a newer draft available: \begin_inset CommandInset href LatexCommand href name "draft-ietf-ipv6-privacy-addrs-v2-*" target "http://www.ietf.org/ids.by.wg/ipv6.html" \end_inset ). Using a random and a static value a new suffix is generated from time to time. Note: this is only reasonable for outgoing client connections and isn't really useful for well-known servers. \end_layout \begin_layout Subsection Manually set \end_layout \begin_layout Standard For servers, it's probably easier to remember simpler addresses, this can also be accommodated. It is possible to assign an additional IPv6 address to an interface, e.g. \end_layout \begin_layout Code 2001:0db8:100:f101::1 \end_layout \begin_layout Standard For manual suffixes like \begin_inset Quotes sld \end_inset ::1 \begin_inset Quotes srd \end_inset shown in the above example, it's required that the 7th most significant bit is set to 0 (the universal/local bit of the automatically generated identifier). Also some other (otherwise unchosen ) bit combinations are reserved for anycast addresses, too. \end_layout \begin_layout Section Prefix lengths for routing \end_layout \begin_layout Standard In the early design phase it was planned to use a fully hierarchical routing approach to reduce the size of the routing tables maximally. The reasons behind this approach were the number of current IPv4 routing entries in core routers (> 400 thousand in 2013), reducing the need of memory in hardware routers (ASIC \begin_inset Quotes sld \end_inset Application Specified Integrated Circuit \begin_inset Quotes srd \end_inset driven) to hold the routing table and increase speed (fewer entries hopefully result in faster lookups). \begin_inset Separator latexpar \end_inset \end_layout \begin_layout Standard \align left Todays view is that routing will be mostly hierarchically designed for networks with only one service provider. With more than one ISP connections, this is not possible, and subject to an issue named multi-homing (infos on multi-homing: \begin_inset CommandInset href LatexCommand href name "drafts-ietf-multi6-*" target "http://www.ietf.org/ids.by.wg/multi6.html" \end_inset , \begin_inset CommandInset href LatexCommand href name "IPv6 Multihoming Solutions" target "http://arneill-py.sacramento.ca.us/ipv6mh/" \end_inset ). \end_layout \begin_layout Subsection Prefix lengths (also known as "netmasks") \end_layout \begin_layout Standard \align left Similar to IPv4, the routable network path for routing to take place. Because standard netmask notation for 128 bits doesn't look nice, designers employed the IPv4 Classless Inter Domain Routing (CIDR, \begin_inset CommandInset href LatexCommand href name "RFC 1519 / Classless Inter-Domain Routing" target "http://www.faqs.org/rfcs/rfc1519.html" \end_inset ) scheme, which specifies the number of bits of the IP address to be used for routing. It is also called the "slash" notation. \end_layout \begin_layout Standard \align left An example: \end_layout \begin_layout Code 2001:0db8:100:1:2:3:4:5/48 \end_layout \begin_layout Standard \align left This notation will be expanded: \end_layout \begin_layout Itemize Network: \end_layout \begin_layout Code 2001:0db8:0100:0000:0000:0000:0000:0000 \end_layout \begin_layout Itemize Netmask: \end_layout \begin_layout Code ffff:ffff:ffff:0000:0000:0000:0000:0000 \end_layout \begin_layout Subsection Matching a route \end_layout \begin_layout Standard Under normal circumstances (no QoS), a lookup in a routing table results in the route with the most significant number of address bits being selected. In other words, the route with the biggest prefix length matches first. \end_layout \begin_layout Standard For example if a routing table shows following entries (list is not complete): \end_layout \begin_layout Code 2001:0db8:100::/48 :: U 1 0 0 sit1 \end_layout \begin_layout Code 2000::/3 ::192.88.99.1 UG 1 0 0 tun6to4 \end_layout \begin_layout Standard Shown destination addresses of IPv6 packets will be routed through shown device \end_layout \begin_layout Code 2001:0db8:100:1:2:3:4:5/48 -> routed through device sit1 \end_layout \begin_layout Code 2001:0db8:200:1:2:3:4:5/48 -> routed through device tun6to4 \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-systemcheck" \end_inset IPv6-ready system check \end_layout \begin_layout Standard \align left Before you can start using IPv6 on a Linux host, you have to test, whether your system is IPv6-ready. You may have to do some work to enable it first. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "systemcheck-kernel" \end_inset IPv6-ready kernel \end_layout \begin_layout Standard \align left Modern Linux distributions already contain IPv6-ready kernels, the IPv6 capability is generally compiled as a module, but it's possible that this module is not loaded automatically on startup. \end_layout \begin_layout Standard \series bold Note: you shouldn't anymore use kernel series 2.2.x, because it's not IPv6-up-to-d ate anymore. Also the IPv6 support in series 2.4.x is no longer improved according to definitions in latest RFCs. It's recommend to use series 2.6.x now. \end_layout \begin_layout Subsection Check for IPv6 support in the current running kernel \end_layout \begin_layout Standard \align left To check, whether your current running kernel supports IPv6, take a look into your \family typewriter /proc \family default -file-system. Following entry must exists: \end_layout \begin_layout Code /proc/net/if_inet6 \end_layout \begin_layout Standard \align left A short automatical test looks like: \end_layout \begin_layout Code # test -f /proc/net/if_inet6 && echo "Running kernel is IPv6 ready" \end_layout \begin_layout Standard \align left If this fails, it is quite likely, that the IPv6 module is not loaded. \end_layout \begin_layout Subsection Try to load IPv6 module \end_layout \begin_layout Standard \align left You can try to load the IPv6 module executing \end_layout \begin_layout Code # modprobe ipv6 \end_layout \begin_layout Standard \align left If this is successful, this module should be listed, testable with following auto-magically line: \end_layout \begin_layout Code # lsmod |grep -w 'ipv6' && echo "IPv6 module successfully loaded" \end_layout \begin_layout Standard \align left And the check shown above should now run successfully. \end_layout \begin_layout Standard Note: unloading the module is currently not supported and can result, under some circumstances, in a kernel crash. \end_layout \begin_layout Subsubsection Automatically loading of module \end_layout \begin_layout Standard Its possible to automatically load the IPv6 module on demand. You only have to add following line in the configuration file of the kernel module loader (normally /etc/modules.conf or /etc/conf.modules): \end_layout \begin_layout Code alias net-pf-10 ipv6 # automatically load IPv6 module on demand \end_layout \begin_layout Standard It's also possible to disable automatically loading of the IPv6 module using following line \end_layout \begin_layout Code alias net-pf-10 off # disable automatically load of IPv6 module on demand \end_layout \begin_layout Standard Additional note: in kernels series 2.6.x, the module loader mechanism was changed. The new configuration file has to be named /etc/modprobe.conf instead of /etc/modules.conf. \end_layout \begin_layout Subsection Compile kernel with IPv6 capabilities \end_layout \begin_layout Standard \align left If both above shown results were negative and your kernel has no IP6 support, than you have the following options: \end_layout \begin_layout Itemize \align left Update your distribution to a current one which supports IPv6 out-of-the-box (recommended for newbies) \end_layout \begin_layout Itemize \align left Compile a new vanilla kernel (easy, if you know which options you needed) \end_layout \begin_layout Itemize Recompile kernel sources given by your Linux distribution (sometimes not so easy) \end_layout \begin_layout Itemize \align left Compile a kernel with USAGI extensions \end_layout \begin_layout Standard \align left If you decide to compile a kernel, you should have previous experience in kernel compiling and read the \begin_inset CommandInset href LatexCommand href name "Linux Kernel HOWTO" target "http://www.tldp.org/HOWTO/Kernel-HOWTO.html" \end_inset . \end_layout \begin_layout Standard A comparison between vanilla and USAGI extended kernels is available on \begin_inset CommandInset href LatexCommand href name "IPv6+Linux-Status-Kernel" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-kernel.html" \end_inset . \end_layout \begin_layout Subsubsection Compiling a vanilla kernel \end_layout \begin_layout Standard More detailed hints about compiling an IPv6-enabled kernel can be found e.g. on \begin_inset CommandInset href LatexCommand href name "IPv6-HOWTO-2#kernel" target "http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO-2.html#kernel" \end_inset . \end_layout \begin_layout Standard Note: you should use whenever possible kernel series 2.6.x or above, because the IPv6 support in series 2.4.x only will no longer get backported features from 2.6.x and IPv6 support in series 2.2.x is hopeless outdated. \end_layout \begin_layout Subsubsection Compiling a kernel with USAGI extensions \end_layout \begin_layout Standard \align left Same as for vanilla kernel, only recommend for advanced users, which are already familiar with IPv6 and kernel compilation. See also \begin_inset CommandInset href LatexCommand href name "USAGI project / FAQ" target "http://www.linux-ipv6.org/faq.html" \end_inset and \begin_inset CommandInset href LatexCommand href name "Obtaining the best IPv6 support with Linux (Article)" target "http://www.deepspace6.net/docs/best_ipv6_support.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/docs/best_ipv6_support.html" \end_inset ). \end_layout \begin_layout Subsection IPv6-ready network devices \end_layout \begin_layout Standard Not all existing network devices have already (or ever) the capability to transport IPv6 packets. A current status can be found at \begin_inset CommandInset href LatexCommand href name "IPv6+Linux-status-kernel.html#transport" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-kernel.html#transport" \end_inset . \end_layout \begin_layout Standard A major issue is that because of the network layer structure of kernel implement ation an IPv6 packet isn't really recognized by it's IP header number (6 instead of 4). It's recognized by the protocol number of the Layer 2 transport protocol. Therefore any transport protocol which doesn't use such protocol number cannot dispatch IPv6 packets. Note: the packet is still transported over the link, but on receivers side, the dispatching won't work (you can see this e.g. using tcpdump). \end_layout \begin_layout Subsubsection Currently known never \begin_inset Quotes sld \end_inset IPv6 capable links \begin_inset Quotes srd \end_inset \end_layout \begin_layout Itemize Serial Line IP (SLIP, \begin_inset CommandInset href LatexCommand href name "RFC 1055 / SLIP" target "http://www.faqs.org/rfcs/rfc1055.html" \end_inset ), should be better called now to SLIPv4, device named: slX \end_layout \begin_layout Itemize Parallel Line IP (PLIP), same like SLIP, device names: plipX \end_layout \begin_layout Itemize ISDN with encapsulation \emph on rawip \emph default , device names: isdnX \end_layout \begin_layout Subsubsection Currently known \begin_inset Quotes sld \end_inset not supported IPv6 capable links \begin_inset Quotes srd \end_inset \end_layout \begin_layout Itemize ISDN with encapsulation \emph on syncppp \emph default , device names: ipppX (design issue of the ipppd, will be merged into more general PPP layer in kernel series 2.5.x) \end_layout \begin_layout Section IPv6-ready network configuration tools \end_layout \begin_layout Standard \align left You wont get very far, if you are running an IPv6-ready kernel, but have no tools to configure IPv6. There are several packages in existence which can configure IPv6. \end_layout \begin_layout Subsection net-tools package \end_layout \begin_layout Standard \align left The net-tool package includes some tools like \family typewriter ifconfig \family default and \family typewriter route \family default , which helps you to configure IPv6 on an interface. Look at the output of \family typewriter ifconfig -? \family default or \family typewriter route -? \family default , if something is shown like IPv6 or inet6, then the tool is IPv6-ready. \end_layout \begin_layout Standard \align left Auto-magically check: \end_layout \begin_layout Code # /sbin/ifconfig -? 2>& 1|grep -qw 'inet6' && echo "utility 'ifconfig' is \end_layout \begin_layout Code ¬ IPv6-ready" \end_layout \begin_layout Standard \align left Same check can be done for \family typewriter route \family default : \end_layout \begin_layout Code # /sbin/route -? 2>& 1|grep -qw 'inet6' && echo "utility 'route' is IPv6-ready" \end_layout \begin_layout Subsection iproute package \end_layout \begin_layout Standard \align left Alexey N. Kuznetsov (current a maintainer of the Linux networking code) created a tool-set which configures networks through the netlink device. Using this tool-set you have more functionality than net-tools provides, but its not very well documented and isn't for the faint of heart. \end_layout \begin_layout Code # /sbin/ip 2>&1 |grep -qw 'inet6' && echo "utility 'ip' is IPv6-ready" \end_layout \begin_layout Standard If the program /sbin/ip isn't found, then I strongly recommend you install the iproute package. \end_layout \begin_layout Itemize You can get it from your Linux distribution (if contained) \end_layout \begin_layout Itemize You're able to look for a proper RPM package at \begin_inset CommandInset href LatexCommand href name "RPMfind/iproute" target "http://rpmfind.net/linux/rpm2html/search.php?query=iproute" \end_inset (sometimes rebuilding of a SRPMS package is recommended) \end_layout \begin_layout Section IPv6-ready test/debug programs \end_layout \begin_layout Standard \align left After you have prepared your system for IPv6, you now want to use IPv6 for network communications. First you should learn how to examine IPv6 packets with a sniffer program. This is strongly recommended because for debugging/troubleshooting issues this can aide in providing a diagnosis very quickly. \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "program-ping6" \end_inset IPv6 ping \end_layout \begin_layout Standard This program is normally included in package \emph on iputils \emph default . It is designed for simple transport tests sending ICMPv6 echo-request packets and wait for ICMPv6 echo-reply packets. \end_layout \begin_layout Standard Usage \end_layout \begin_layout Code # ping6 \end_layout \begin_layout Code # ping6 \end_layout \begin_layout Code # ping6 [-I ] \end_layout \begin_layout Standard Some implementation also support % suffix instead of using -I , e.g. \end_layout \begin_layout Code # ping6 % \end_layout \begin_layout Standard Example \end_layout \begin_layout Code # ping6 -c 1 ::1 \end_layout \begin_layout Code PING ::1(::1) from ::1 : 56 data bytes \end_layout \begin_layout Code 64 bytes from ::1: icmp_seq=0 hops=64 time=292 usec \end_layout \begin_layout Code \end_layout \begin_layout Code --- ::1 ping statistics --- \end_layout \begin_layout Code 1 packets transmitted, 1 packets received, 0% packet loss \end_layout \begin_layout Code round-trip min/avg/max/mdev = 0.292/0.292/0.292/0.000 ms \end_layout \begin_layout Standard Hint: ping6 needs raw access to socket and therefore root permissions. So if non-root users cannot use ping6 then there are two possible problems: \end_layout \begin_layout Enumerate ping6 is not in users path (probably, because ping6 is generally stored in /usr/sbin -> add path (not really recommended) \end_layout \begin_layout Enumerate ping6 doesn't execute properly, generally because of missing root permissions -> chmod u+s /usr/sbin/ping6 \end_layout \begin_layout Subsubsection Specifying interface for IPv6 ping \end_layout \begin_layout Standard Using link-local addresses for an IPv6 ping, the kernel does not know through which (physically or virtual) device it must send the packet - each device has a link-local address. A try will result in following error message: \end_layout \begin_layout Code # ping6 fe80::212:34ff:fe12:3456 \end_layout \begin_layout Code connect: Invalid argument \end_layout \begin_layout Standard In this case you have to specify the interface additionally like shown here: \end_layout \begin_layout Code # ping6 -I eth0 -c 1 fe80::2e0:18ff:fe90:9205 \end_layout \begin_layout Code PING fe80::212:23ff:fe12:3456(fe80::212:23ff:fe12:3456) from \end_layout \begin_layout Code ¬ fe80::212:34ff:fe12:3478 eth0: 56 data bytes \end_layout \begin_layout Code 64 bytes from fe80::212:23ff:fe12:3456: icmp_seq=0 hops=64 time=445 usec \end_layout \begin_layout Code \end_layout \begin_layout Code --- fe80::2e0:18ff:fe90:9205 ping statistics --- \end_layout \begin_layout Code 1 packets transmitted, 1 packets received, 0% packet loss round-trip \end_layout \begin_layout Code ¬ min/avg/max/mdev = 0.445/0.445/0.445/0.000 ms \end_layout \begin_layout Standard Example for % notation: \end_layout \begin_layout Code # ping6 -c 1 fe80::2e0:18ff:fe90:9205%eth0 \end_layout \begin_layout Subsubsection Ping6 to multicast addresses \end_layout \begin_layout Standard An interesting mechanism to detect IPv6-active hosts on a link is to ping6 to the link-local all-node multicast address: \end_layout \begin_layout Code # ping6 -I eth0 ff02::1 \end_layout \begin_layout Code PING ff02::1(ff02::1) from fe80:::2ab:cdff:feef:0123 eth0: 56 data bytes \end_layout \begin_layout Code 64 bytes from ::1: icmp_seq=1 ttl=64 time=0.104 ms \end_layout \begin_layout Code 64 bytes from fe80::212:34ff:fe12:3450: icmp_seq=1 ttl=64 time=0.549 ms (DUP!) \end_layout \begin_layout Standard Example for % notation: \end_layout \begin_layout Code # ping6 ff02::1%eth0 \end_layout \begin_layout Standard Unlike in IPv4, where replies to a ping on the broadcast address can be disabled, in IPv6 currently this behavior cannot be disable except by local IPv6 firewalling. \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "program-traceroute6" \end_inset IPv6 traceroute6 \end_layout \begin_layout Standard This program is normally included in package \emph on iputils \emph default . It's a program similar to IPv4 traceroute. Below you will see an example: \end_layout \begin_layout Code # traceroute6 www.6bone.net \end_layout \begin_layout Code traceroute to 6bone.net (3ffe:b00:c18:1::10) from 2001:0db8:0000:f101::2, 30 \end_layout \begin_layout Code ¬ hops max, 16 byte packets \end_layout \begin_layout Code 1 localipv6gateway (2001:0db8:0000:f101::1) 1.354 ms 1.566 ms 0.407 ms \end_layout \begin_layout Code 2 swi6T1-T0.ipv6.switch.ch (3ffe:2000:0:400::1) 90.431 ms 91.956 ms 92.377 ms \end_layout \begin_layout Code 3 3ffe:2000:0:1::132 (3ffe:2000:0:1::132) 118.945 ms 107.982 ms 114.557 ms \end_layout \begin_layout Code 4 3ffe:c00:8023:2b::2 (3ffe:c00:8023:2b::2) 968.468 ms 993.392 ms 973.441 ms \end_layout \begin_layout Code 5 3ffe:2e00:e:c::3 (3ffe:2e00:e:c::3) 507.784 ms 505.549 ms 508.928 ms \end_layout \begin_layout Code 6 www.6bone.net (3ffe:b00:c18:1::10) 1265.85 ms * 1304.74 ms \end_layout \begin_layout Standard Note: unlike some modern versions of IPv4 traceroute, which can use ICMPv4 echo-request packets as well as UDP packets (default), current IPv6-traceroute is only able to send UDP packets. As you perhaps already know, ICMP echo-request packets are more accepted by firewalls or ACLs on routers inbetween than UDP packets. \end_layout \begin_layout Standard \lang ngerman If a dedicated interface must be specified, this can be done by -i or using
%. \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "program-tracepath6" \end_inset IPv6 tracepath6 \end_layout \begin_layout Standard This program is normally included in package \emph on iputils \emph default . It's a program like traceroute6 and traces the path to a given destination discovering the MTU along this path. Below you will see an example: \end_layout \begin_layout Code # tracepath6 www.6bone.net \end_layout \begin_layout Code 1?: [LOCALHOST] pmtu 1480 \end_layout \begin_layout Code 1: 3ffe:401::2c0:33ff:fe02:14 150.705ms \end_layout \begin_layout Code 2: 3ffe:b00:c18::5 267.864ms \end_layout \begin_layout Code 3: 3ffe:b00:c18::5 asymm 2 266.145ms pmtu 1280 \end_layout \begin_layout Code 3: 3ffe:3900:5::2 asymm 4 346.632ms \end_layout \begin_layout Code 4: 3ffe:28ff:ffff:4::3 asymm 5 365.965ms \end_layout \begin_layout Code 5: 3ffe:1cff:0:ee::2 asymm 4 534.704ms \end_layout \begin_layout Code 6: 3ffe:3800::1:1 asymm 4 578.126ms !N \end_layout \begin_layout Code Resume: pmtu 1280 \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "program-tcpdump" \end_inset IPv6 tcpdump \end_layout \begin_layout Standard On Linux, tcpdump is the major tool for packet capturing. Below you find some examples. IPv6 support is normally built-in in current releases of version 3.6. \end_layout \begin_layout Standard tcpdump uses expressions for filtering packets to minimize the noise: \end_layout \begin_layout Itemize icmp6: filters native ICMPv6 traffic \end_layout \begin_layout Itemize ip6: filters native IPv6 traffic (including ICMPv6) \end_layout \begin_layout Itemize proto ipv6: filters tunneled IPv6-in-IPv4 traffic \end_layout \begin_layout Itemize not port ssh: to suppress displaying SSH packets for running tcpdump in a remote SSH session \end_layout \begin_layout Standard Also some command line options are very useful to catch and print more informati on in a packet, mostly interesting for digging into ICMPv6 packets: \end_layout \begin_layout Itemize \begin_inset Quotes eld \end_inset -s 512 \begin_inset Quotes erd \end_inset : increase the snap length during capturing of a packet to 512 bytes \end_layout \begin_layout Itemize \begin_inset Quotes eld \end_inset -vv \begin_inset Quotes erd \end_inset : really verbose output \end_layout \begin_layout Itemize \begin_inset Quotes eld \end_inset -n \begin_inset Quotes erd \end_inset : don't resolve addresses to names, useful if reverse DNS resolving isn't working proper \end_layout \begin_layout Subsubsection IPv6 ping to \size footnotesize 2001:0db8:100:f101::1 \size default native over a local link \end_layout \begin_layout Code # tcpdump -t -n -i eth0 -s 512 -vv ip6 or proto ipv6 \end_layout \begin_layout Code tcpdump: listening on eth0 \end_layout \begin_layout Code 2001:0db8:100:f101:2e0:18ff:fe90:9205 > 2001:0db8:100:f101::1: icmp6: echo \end_layout \begin_layout Code ¬ request (len 64, hlim 64) \end_layout \begin_layout Code 2001:0db8:100:f101::1 > 2001:0db8:100:f101:2e0:18ff:fe90:9205: icmp6: echo \end_layout \begin_layout Code ¬ reply (len 64, hlim 64) \end_layout \begin_layout Subsubsection IPv6 ping to \size footnotesize 2001:0db8:100::1 \size default routed through an IPv6-in-IPv4-tunnel \end_layout \begin_layout Standard 1.2.3.4 and 5.6.7.8 are tunnel endpoints (all addresses are examples) \end_layout \begin_layout Code # tcpdump -t -n -i ppp0 -s 512 -vv ip6 or proto ipv6 \end_layout \begin_layout Code tcpdump: listening on ppp0 \end_layout \begin_layout Code 1.2.3.4 > 5.6.7.8: 2002:ffff:f5f8::1 > 2001:0db8:100::1: icmp6: echo request \end_layout \begin_layout Code ¬ (len 64, hlim 64) (DF) (ttl 64, id 0, len 124) \end_layout \begin_layout Code 5.6.7.8 > 1.2.3.4: 2001:0db8:100::1 > 2002:ffff:f5f8::1: icmp6: echo reply (len \end_layout \begin_layout Code ¬ 64, hlim 61) (ttl 23, id 29887, len 124) \end_layout \begin_layout Code 1.2.3.4 > 5.6.7.8: 2002:ffff:f5f8::1 > 2001:0db8:100::1: icmp6: echo request \end_layout \begin_layout Code ¬ (len 64, hlim 64) (DF) (ttl 64, id 0, len 124) \end_layout \begin_layout Code 5.6.7.8 > 1.2.3.4: 2001:0db8:100::1 > 2002:ffff:f5f8::1: icmp6: echo reply (len \end_layout \begin_layout Code ¬ 64, hlim 61) (ttl 23, id 29919, len 124) \end_layout \begin_layout Section IPv6-ready programs \end_layout \begin_layout Standard Current distributions already contain the most needed IPv6 enabled client and servers. See first on \begin_inset CommandInset href LatexCommand href name "IPv6+Linux-Status-Distribution" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-distributions.html" \end_inset . If still not included, you can check \lang ngerman \begin_inset CommandInset href LatexCommand href name "Current Status of IPv6 Support for Networking Applications" target "http://www.deepspace6.net/docs/ipv6_status_page_apps.html" \end_inset \lang english whether the program is already ported to IPv6 and usable with Linux. For common used programs there are some hints available here later in this document. \end_layout \begin_layout Section IPv6-ready client programs (selection) \end_layout \begin_layout Standard To run the following shown tests, it's required that your system is IPv6 enabled, and some examples show addresses which only can be reached if a connection to the global IPv6 network is available. \end_layout \begin_layout Standard Note: if using names instead of dedicated IPv4/IPv6 addresses which resolves to IPv4 and IPv6 addresses, some command line clients support explicitly use of specified protocol. Usually such clients have option \begin_inset Quotes sld \end_inset -4 \begin_inset Quotes srd \end_inset for IPv4 and \begin_inset Quotes sld \end_inset -6 \begin_inset Quotes srd \end_inset for IPv6. \end_layout \begin_layout Subsection Checking DNS for resolving IPv6 addresses \end_layout \begin_layout Standard Because of security updates in the last years every Domain Name System (DNS) server should run newer software which already understands the (intermediate) IPv6 address-type AAAA (the newer one named A6 isn't still common at the moment because only supported using BIND9 and newer and also the non-existent support of root domain IP6.ARPA). A simple test whether the used system can resolve IPv6 addresses is \end_layout \begin_layout Code # host -t AAAA www.join.uni-muenster.de \end_layout \begin_layout Standard and should show something like following: \end_layout \begin_layout Code www.join.uni-muenster.de. is an alias for tolot.join.uni-muenster.de. \end_layout \begin_layout Code tolot.join.uni-muenster.de. has AAAA address \end_layout \begin_layout Code ¬ 2001:638:500:101:2e0:81ff:fe24:37c6 \end_layout \begin_layout Subsection IPv6-ready telnet clients \end_layout \begin_layout Standard IPv6-ready telnet clients are available. A simple test can be done with \end_layout \begin_layout Code $ telnet 3ffe:400:100::1 80 \end_layout \begin_layout Code Trying 3ffe:400:100::1... \end_layout \begin_layout Code Connected to 3ffe:400:100::1. \end_layout \begin_layout Code Escape character is '^]'. \end_layout \begin_layout Code HEAD / HTTP/1.0 \end_layout \begin_layout Code \end_layout \begin_layout Code HTTP/1.1 200 OK \end_layout \begin_layout Code Date: Sun, 16 Dec 2001 16:07:21 \end_layout \begin_layout Code GMT Server: Apache/2.0.28 (Unix) \end_layout \begin_layout Code Last-Modified: Wed, 01 Aug 2001 21:34:42 GMT \end_layout \begin_layout Code ETag: "3f02-a4d-b1b3e080" \end_layout \begin_layout Code Accept-Ranges: bytes \end_layout \begin_layout Code Content-Length: 2637 \end_layout \begin_layout Code Connection: close \end_layout \begin_layout Code Content-Type: text/html; charset=ISO-8859-1 \end_layout \begin_layout Code \end_layout \begin_layout Code Connection closed by foreign host. \end_layout \begin_layout Standard If the telnet client don't understand the IPv6 address and says something like \begin_inset Quotes sld \end_inset cannot resolve hostname \begin_inset Quotes srd \end_inset , then it's not IPv6-enabled. \end_layout \begin_layout Subsection IPv6-ready ssh clients \end_layout \begin_layout Subsubsection openssh \end_layout \begin_layout Standard Current versions of openssh are IPv6-ready. Depending on configuring before compiling it has two behavior. \end_layout \begin_layout Itemize --without-ipv4-default: the client tries an IPv6 connect first automatically and fall back to IPv4 if not working \end_layout \begin_layout Itemize --with-ipv4-default: default connection is IPv4, IPv6 connection must be force like following example shows \end_layout \begin_layout Code $ ssh -6 ::1 \end_layout \begin_layout Code user@::1's password: ****** \end_layout \begin_layout Code [user@ipv6host user]$ \end_layout \begin_layout Standard If your ssh client doesn't understand the option \begin_inset Quotes sld \end_inset -6 \begin_inset Quotes srd \end_inset then it's not IPv6-enabled, like most ssh version 1 packages. \end_layout \begin_layout Subsubsection ssh.com \end_layout \begin_layout Standard SSH.com's SSH client and server is also IPv6 aware now and is free for all Linux and FreeBSD machine regardless if used for personal or commercial use. \end_layout \begin_layout Subsection IPv6-ready web browsers \end_layout \begin_layout Standard A current status of IPv6 enabled web browsers is available at \begin_inset CommandInset href LatexCommand href name "Current Status of IPv6 Support for Networking Applications - HTTP" target "http://www.deepspace6.net/docs/ipv6_status_page_apps.html#http" \end_inset . \end_layout \begin_layout Standard Most of them have unresolved problems at the moment \end_layout \begin_layout Enumerate If using an IPv4 only proxy in the settings, IPv6 requests will be sent to the proxy, but the proxy will fail to understand the request and the request fails. Solution: update proxy software (see later). \end_layout \begin_layout Enumerate Automatic proxy settings (*.pac) cannot be extended to handle IPv6 requests differently (e.g. don't use proxy) because of their nature (written in Java-script and well hard coded in source like to be seen in Mozilla source code). \end_layout \begin_layout Standard Also older versions don't understand an URL with IPv6 encoded addresses like \begin_inset CommandInset href LatexCommand href name "http://[2001:4dd0:f838:a006::6]/" target "http://[2001:4dd0:f838:a006::6]/" \end_inset , IPv6 address of \begin_inset CommandInset href LatexCommand href name "http://www.ipv6.bieringer.de/" target "http://www.ipv6.bieringer.de/" \end_inset (this given URLs only works with an IPv6-enabled browser!). \end_layout \begin_layout Standard A short test is to try shown URL with a given browser and using no proxy. \end_layout \begin_layout Subsubsection URLs for testing \end_layout \begin_layout Standard A good starting point for browsing using IPv6 is \begin_inset CommandInset href LatexCommand href name "http://www.kame.net/" target "http://www.kame.net/" \end_inset . If the turtle on this page is animated, the connection is via IPv6, otherwise the turtle is static. \end_layout \begin_layout Standard \lang ngerman Other test servers are e.g. \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "What Is My IPv6" target "http://www.whatismyipv6.com/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "ip.bieringer.de" target "http://ip.bieringer.de/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "IPv6 Test" target "http://ipv6-test.com/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "test-ipv6.com" target "http://test-ipv6.com/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "The ICSI Netalyzr" target "http://netalyzr.icsi.berkeley.edu/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "Speedtest Comcast" target "http://speedtest.comcast.net/" \end_inset , \begin_inset CommandInset href LatexCommand href name "IPv6 Speedtest Comcast" target "http://ipv6.speedtest.comcast.net/" \end_inset \end_layout \begin_layout Section IPv6-ready server programs \end_layout \begin_layout Standard In this part of this HOWTO, more client specific issues are mentioned. Therefore hints for IPv6-ready servers like sshd, httpd, telnetd, etc. are shown below in \begin_inset CommandInset ref LatexCommand ref name "Hints for IPv6-enabled daemons" reference "chapter-hints-daemons" \end_inset . \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "faq-ipv6-ready-system-check" \end_inset FAQ (IPv6-ready system check) \end_layout \begin_layout Subsection Using tools \end_layout \begin_layout Subsubsection Q: Cannot ping6 to link-local addresses \end_layout \begin_layout Standard Error message: " \emph on connect: Invalid argument \emph default " \end_layout \begin_layout Standard Kernel doesn't know, which physical or virtual link you want to use to send such ICMPv6 packets. Therefore it displays this error message. \end_layout \begin_layout Standard Solution: Specify interface like: \begin_inset Quotes sld \end_inset ping6 \series bold -I eth0 \series default fe80::2e0:18ff:fe90:9205 \begin_inset Quotes srd \end_inset , see also \begin_inset CommandInset ref LatexCommand ref name "program ping6 usage" reference "program-ping6" \end_inset . \end_layout \begin_layout Subsubsection Q: Cannot ping6 or traceroute6 as normal user \end_layout \begin_layout Standard Error message: \begin_inset Quotes sld \end_inset \emph on icmp socket: Operation not permitted \emph default \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard These utilities create special ICMPv6 packets and send them out. This is done by using raw sockets in the kernel. But raw sockets can only be used by the \begin_inset Quotes sld \end_inset root \begin_inset Quotes srd \end_inset user. Therefore normal users get such error message. \end_layout \begin_layout Standard Solution: If it's really needed that all users should be able to use these utilities, you can add the \begin_inset Quotes sld \end_inset suid \begin_inset Quotes srd \end_inset bit using \begin_inset Quotes srd \end_inset chmod u+s /path/to/program \begin_inset Quotes srd \end_inset , see also \begin_inset CommandInset ref LatexCommand ref name "program ping6 usage" reference "program-ping6" \end_inset . If not all users should be able to, you can change the group of the program to e.g. \begin_inset Quotes sld \end_inset wheel \begin_inset Quotes srd \end_inset , add these power users to this group and remove the execution bit for other users using \begin_inset Quotes sld \end_inset chmod o-rwx /path/to/program \begin_inset Quotes srd \end_inset . Or configure \begin_inset Quotes sld \end_inset sudo \begin_inset Quotes srd \end_inset to enable your security policy. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-configuration-interface" \end_inset Configuring interfaces \end_layout \begin_layout Section Different network devices \end_layout \begin_layout Standard On a node, there exist different network devices. They can be collected in classes \end_layout \begin_layout Itemize Physically bounded, like eth0, tr0 \end_layout \begin_layout Itemize Virtually existing, like ppp0, tun0, tap0, sit0, isdn0, ippp0 \end_layout \begin_layout Subsection Physically bounded \end_layout \begin_layout Standard Physically bounded interfaces like Ethernet or Token-Ring are normal ones and need no special treatment. \end_layout \begin_layout Subsection Virtually bounded \end_layout \begin_layout Standard Virtually bounded interfaces always need special support \end_layout \begin_layout Subsubsection IPv6-in-IPv4 tunnel interfaces \end_layout \begin_layout Standard These interfaces are normally named \series bold sit \emph on x \series default \emph default . The name \emph on sit \emph default is a shortcut for \series bold S \series default imple \series bold I \series default nternet \series bold T \series default ransition. This device has the capability to encapsulate IPv6 packets into IPv4 ones and tunnel them to a foreign endpoint. \end_layout \begin_layout Standard \series bold sit0 \series default has a special meaning and cannot be used for dedicated tunnels. \end_layout \begin_layout Subsubsection PPP interfaces \end_layout \begin_layout Standard PPP interfaces get their IPv6 capability from an IPv6 enabled PPP daemon. \end_layout \begin_layout Subsubsection ISDN HDLC interfaces \end_layout \begin_layout Standard IPv6 capability for HDLC with encapsulation \series bold ip \series default is already built-in in the kernel \end_layout \begin_layout Subsubsection ISDN PPP interfaces \end_layout \begin_layout Standard ISDN PPP interfaces (ippp) aren't IPv6 enabled by kernel. Also there are also no plans to do that because in kernel 2.5.+ they will be replaced by a more generic ppp interface layer. \end_layout \begin_layout Subsubsection SLIP + PLIP \end_layout \begin_layout Standard Like mentioned earlier, this interfaces don't support IPv6 transport (sending is OK, but dispatching on receiving don't work). \end_layout \begin_layout Subsubsection Ether-tap device \end_layout \begin_layout Standard Ether-tap devices are IPv6-enabled and also stateless configured. For use, the module \begin_inset Quotes sld \end_inset ethertap \begin_inset Quotes srd \end_inset has to be loaded before. \end_layout \begin_layout Subsubsection tun devices \end_layout \begin_layout Standard Currently not tested by me. \end_layout \begin_layout Subsubsection ATM \end_layout \begin_layout Standard 01/2002: Aren't currently supported by vanilla kernel, supported by USAGI extension \end_layout \begin_layout Subsubsection Others \end_layout \begin_layout Standard Did I forget an interface?... \end_layout \begin_layout Section Bringing interfaces up/down \end_layout \begin_layout Standard Two methods can be used to bring interfaces up or down. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # ip link set dev up \end_layout \begin_layout Code # ip link set dev down \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code \end_layout \begin_layout Code # ip link set dev eth0 up \end_layout \begin_layout Code # ip link set dev eth0 down \end_layout \begin_layout Subsection Using "ifconfig" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/ifconfig up \end_layout \begin_layout Code # /sbin/ifconfig down \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ifconfig eth0 up \end_layout \begin_layout Code # /sbin/ifconfig eth0 down \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-configuration-address" \end_inset Configuring IPv6 addresses \end_layout \begin_layout Standard \align left There are different ways to configure an IPv6 address on an interface. You can use use "ifconfig" or "ip". \end_layout \begin_layout Section Displaying existing IPv6 addresses \end_layout \begin_layout Standard \align left First you should check, whether and which IPv6 addresses are already configured (perhaps auto-magically during stateless auto-configuration). \end_layout \begin_layout Standard Just note that addresses beginning with \begin_inset Quotes sld \end_inset fec0 \begin_inset Quotes srd \end_inset are deprecated, but shown here for completness! \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 addr show dev \end_layout \begin_layout Standard Example for a static configured host: \end_layout \begin_layout Code # /sbin/ip -6 addr show dev eth0 \end_layout \begin_layout Code 2: eth0: \end_layout \begin_layout Standard Example (output filtered with grep to display only IPv6 addresses). Here you see different IPv6 addresses with different scopes. \end_layout \begin_layout Code # /sbin/ifconfig eth0 |grep "inet6 addr:" \end_layout \begin_layout Code inet6 addr: fe80::210:a4ff:fee3:9566/10 Scope:Link \end_layout \begin_layout Code inet6 addr: 2001:0db8:0:f101::1/64 Scope:Global \end_layout \begin_layout Code inet6 addr: fec0:0:0:f101::1/64 Scope:Site \end_layout \begin_layout Section Add an IPv6 address \end_layout \begin_layout Standard Adding an IPv6 address is similar to the mechanism of "IP ALIAS" addresses in Linux IPv4 addressed interfaces. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 addr add / dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 addr add 2001:0db8:0:f101::1/64 dev eth0 \end_layout \begin_layout Subsection Using "ifconfig" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/ifconfig inet6 add / \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ifconfig eth0 inet6 add 2001:0db8:0:f101::1/64 \end_layout \begin_layout Section Removing an IPv6 address \end_layout \begin_layout Standard \align left Not so often needed, be carefully with removing non existent IPv6 address, sometimes using older kernels it results in a crash. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 addr del / dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 addr del 2001:0db8:0:f101::1/64 dev eth0 \end_layout \begin_layout Subsection Using "ifconfig" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/ifconfig inet6 del / \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ifconfig eth0 inet6 del 2001:0db8:0:f101::1/64 \end_layout \begin_layout Section Automatic IPv6 Address Configuration \end_layout \begin_layout Standard In case, a Router Advertisement is received by a client, and IPv6 autoconfigurat ion is enabled (default on non-router), the client configures itself an IPv6 address according to the prefix contained in the advertisement (see also \begin_inset CommandInset ref LatexCommand ref reference "hints-daemons-radvd" \end_inset ). \end_layout \begin_layout Section Enable Privacy Extension \end_layout \begin_layout Standard Privacy Extension as described in \begin_inset CommandInset href LatexCommand href name "RFC 4941 / Privacy Extensions for Stateless Address Autoconfiguration in IPv6" target "http://www.faqs.org/rfcs/rfc4941.html" \end_inset (obsoleted \begin_inset CommandInset href LatexCommand href name "RFC 3041" target "http://www.faqs.org/rfcs/rfc3041.html" \end_inset ) is replacing the static interface ID (mostly based on word-wide unique MAC address) used during autoconfiguration by a pseudo-random one and generatin g from time to time a new one deprecating the old one. \end_layout \begin_layout Subsection Enable Privacy Extension using sysctl \end_layout \begin_layout Subsection* Temporary activation \end_layout \begin_layout Standard Enable privacy extension for e.g. interface \begin_inset Quotes sld \end_inset eth0 \begin_inset Quotes srd \end_inset and prefer the generated address: \end_layout \begin_layout Code # sysctl -w net.ipv6.conf.eth0.use_tempaddr=2 \end_layout \begin_layout Standard Afterwards, restart of the interface is necessary \end_layout \begin_layout Code # ip link set dev eth0 down \end_layout \begin_layout Code # ip link set dev eth0 up \end_layout \begin_layout Standard Once a router advertisement is received, the result should look like following \end_layout \begin_layout Code # ip -6 addr show dev eth0 \end_layout \begin_layout Code 2: eth0: mtu 1500 qlen 1000 \end_layout \begin_layout Code inet6 2001:db8:0:1:8992:3c03:d6e2:ed72/64 scope global secondary dynamic <- pseudo-random IID \end_layout \begin_layout Code valid_lft 604711sec preferred_lft 86311sec \end_layout \begin_layout Code inet6 2001:db8:0:1::224:21ff:fe01:2345/64 scope global <- IID based on MAC \end_layout \begin_layout Code valid_lft 604711sec preferred_lft 86311sec \end_layout \begin_layout Code ... \end_layout \begin_layout Subsection* Permanent activation \end_layout \begin_layout Standard For permanent activation, either a special initscript value per interface will enable privacy or an entry in the /etc/sysctl.conf file like \end_layout \begin_layout Code net.ipv6.conf.eth0.use_tempaddr=2 \end_layout \begin_layout Standard Note: interface must already exists with proper name when sysctl.conf is applied. If this is not the case (e.g. after reboot) one has to configure privacy for all interfaces by default: \end_layout \begin_layout Code net.ipv6.conf.all.use_tempaddr=2 \end_layout \begin_layout Code net.ipv6.conf.default.use_tempaddr=2 \end_layout \begin_layout Standard Changed/added values in /etc/sysctl.conf can be activated during runtime, but at least an interface down/up or a reboot is recommended. \end_layout \begin_layout Code # sysctl -p \end_layout \begin_layout Subsection Enable Privacy Extension using NetworkManager \end_layout \begin_layout Standard Modern (client) systems are using NetworkManager for configuring interfaces. A command line tool is built-in which can be used to change settings which are not available via GUI. \end_layout \begin_layout Standard Examples based on version 0.9.9.1-5.git20140319.fc21 \end_layout \begin_layout Standard Check existing interfaces with: \end_layout \begin_layout Code # nmcli connection \end_layout \begin_layout Code NAME UUID TYPE DEVICE \end_layout \begin_layout Code ens4v1 d0fc2b2e-5fa0-4675-96b5-b723ca5c46db 802-3-ethernet ens4v1 \end_layout \begin_layout Standard Current amount of IPv6 privacy extension addresses can be checked with \end_layout \begin_layout Code # ip -o addr show dev ens4v1 | grep temporary | wc -l \end_layout \begin_layout Code 0 \end_layout \begin_layout Standard Current IPv6 privacy extension settings can be checked with \end_layout \begin_layout Code # nmcli connection show ens4v1 |grep ip6-privacy \end_layout \begin_layout Code ipv6.ip6-privacy: -1 (unknown) \end_layout \begin_layout Standard Enable IPv6 privacy extension and restart interface \end_layout \begin_layout Code # nmcli connection modify ens4v1 ipv6.ip6-privacy 2 \end_layout \begin_layout Code # nmcli connection down ens4v1; nmcli connection up ens4v1 \end_layout \begin_layout Standard New IPv6 privacy extension settings can be checked with \end_layout \begin_layout Code # nmcli connection show ens4v1 |grep ip6-privacy \end_layout \begin_layout Code ipv6.ip6-privacy: 2 (active, prefer temporary IP) \end_layout \begin_layout Standard Now IPv6 privacy extension addresses are configured on the interface \end_layout \begin_layout Code # ip -o addr show dev ens4v1 | grep temporary | wc -l \end_layout \begin_layout Code 2 \end_layout \begin_layout Subsection Test real use of Privacy Extension IPv6 Addresses \end_layout \begin_layout Standard Whether the IPv6 address with an Interface ID generated by Privacy Extension is really used for outgoing connections, one can browse to \begin_inset CommandInset href LatexCommand href name "http://ip.bieringer.de/" target "http://ip.bieringer.de/" \end_inset , in case EUI64_SCOPE shows \begin_inset Quotes sld \end_inset iid-privacy \begin_inset Quotes srd \end_inset , then everything is working fine. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-configuration-route" \end_inset Configuring normal IPv6 routes \end_layout \begin_layout Standard \align left If you want to leave your link and want to send packets in the world wide IPv6-Internet, you need routing. If there is already an IPv6 enabled router on your link, it's possible enough to add IPv6 routes. \end_layout \begin_layout Standard Just note that addresses beginning with \begin_inset Quotes sld \end_inset fec0 \begin_inset Quotes srd \end_inset are deprecated, but shown here for completness! \end_layout \begin_layout Section Displaying existing IPv6 routes \end_layout \begin_layout Standard \align left First you should check, whether and which IPv6 addresses are already configured (perhaps auto-magically during auto-configuration). \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 route show [dev ] \end_layout \begin_layout Standard \align left Example: \end_layout \begin_layout Code # /sbin/ip -6 route show dev eth0 \end_layout \begin_layout Code 2001:0db8:0:f101::/64 proto kernel metric 256 mtu 1500 advmss 1440 \end_layout \begin_layout Code fe80::/10 proto kernel metric 256 mtu 1500 advmss 1440 \end_layout \begin_layout Code ff00::/8 proto kernel metric 256 mtu 1500 advmss 1440 \end_layout \begin_layout Code default proto kernel metric 256 mtu 1500 advmss 1440 \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 \end_layout \begin_layout Standard \align left Example (output is filtered for interface eth0). Here you see different IPv6 routes for different addresses on a single interface. \end_layout \begin_layout Code # /sbin/route -A inet6 |grep -w "eth0" \end_layout \begin_layout Code 2001:0db8:0:f101 ::/64 :: UA 256 0 0 eth0 <- Interface route for global \end_layout \begin_layout Code ¬ address \end_layout \begin_layout Code fe80::/10 :: UA 256 0 0 eth0 <- Interface route for link-local \end_layout \begin_layout Code ¬ address \end_layout \begin_layout Code ff00::/8 :: UA 256 0 0 eth0 <- Interface route for all multicast \end_layout \begin_layout Code ¬ addresses \end_layout \begin_layout Code ::/0 :: UDA 256 0 0 eth0 <- Automatic default route \end_layout \begin_layout Section Add an IPv6 route through a gateway \end_layout \begin_layout Standard \align left Mostly needed to reach the outside with IPv6 using an IPv6-enabled router on your link. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 route add / via \end_layout \begin_layout Code ¬ [dev ] \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 route add default via 2001:0db8:0:f101::1 \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 add / gw \end_layout \begin_layout Code ¬ [dev ] \end_layout \begin_layout Standard \align left A device can be needed, too, if the IPv6 address of the gateway is a link local one. \end_layout \begin_layout Standard Following shown example adds a default route through gateway \family typewriter \lang afrikaans 2001:0db8:0:f101::1 \end_layout \begin_layout Code # /sbin/route -A inet6 add default gw 2001:0db8:0:f101::1 \end_layout \begin_layout Section Removing an IPv6 route through a gateway \end_layout \begin_layout Standard \align left Not so often needed manually, mostly done by network configure scripts on shutdown (full or per interface) \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/ip -6 route del / via \end_layout \begin_layout Code ¬ [dev ] \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 route del default via 2001:0db8:0:f101::1 \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 del / gw [dev \end_layout \begin_layout Code ¬ ] \end_layout \begin_layout Standard Example for removing upper added route again: \end_layout \begin_layout Code # /sbin/route -A inet6 del default gw 2001:0db8:0:f101::1 \end_layout \begin_layout Section Add an IPv6 route through an interface \end_layout \begin_layout Standard \align left Not often needed, sometimes in cases of dedicated point-to-point links. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/ip -6 route add / dev \end_layout \begin_layout Code ¬ metric 1 \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 route add default dev eth0 metric 1 \end_layout \begin_layout Standard Metric \begin_inset Quotes sld \end_inset 1 \begin_inset Quotes srd \end_inset is used here to be compatible with the metric used by route, because the default metric on using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset is \begin_inset Quotes sld \end_inset 1024 \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 add / dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/route -A inet6 add default dev eth0 \end_layout \begin_layout Section Removing an IPv6 route through an interface \end_layout \begin_layout Standard \align left Not so often needed to use by hand, configuration scripts will use such on shutdown. \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 route del / dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 route del default dev eth0 \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard \align left Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 del / dev \end_layout \begin_layout Standard \align left Example: \end_layout \begin_layout Code # /sbin/route -A inet6 del default dev eth0 \end_layout \begin_layout Section FAQ for IPv6 routes \end_layout \begin_layout Subsection Support of an IPv6 default route \end_layout \begin_layout Standard One idea of IPv6 was a hierachical routing, therefore only less routing entries are needed in routers. \end_layout \begin_layout Standard There are some issues in current Linux kernels: \end_layout \begin_layout Subsubsection Clients (not routing any packet!) \end_layout \begin_layout Standard Client can setup a default route like prefix \begin_inset Quotes sld \end_inset ::/0 \begin_inset Quotes srd \end_inset , they also learn such route on autoconfiguration e.g. using radvd on the link like following example shows: \end_layout \begin_layout Code # ip -6 route show | grep ^default \end_layout \begin_layout Code default via fe80::212:34ff:fe12:3450 dev eth0 proto kernel metric 1024 expires \end_layout \begin_layout Code ¬ 29sec mtu 1500 advmss 1440 \end_layout \begin_layout Subsubsection Routers in case of packet forwarding \end_layout \begin_layout Standard Older Linux kernel (at least <= 2.4.17) don't support default routes. You can set them up, but the route lookup fails when a packet should be forwarded (normal intention of a router). If you're still using such older kernel, \begin_inset Quotes sld \end_inset default routing \begin_inset Quotes srd \end_inset can be setup using the currently used global address prefix \begin_inset Quotes sld \end_inset 2000::/3 \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Standard Note: take care about default routing without address filtering on edge routers. Otherwise unwanted multicast or site-local traffic can leave the edge. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-Neighbor-Discovery" \end_inset Neighbor Discovery \end_layout \begin_layout Standard Neighbor discovery was the IPv6 successor for the ARP (Address Resolution Protocol) in IPv4. You can retrieve information about the current neighbors, in addition you can set and delete entries. The kernel keeps tracking of successful neighbor detection (like ARP in IPv4). You can dig into the learnt table using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Section Displaying neighbors using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard With following command you can display the learnt or configured IPv6 neighbors \end_layout \begin_layout Code # ip -6 neigh show [dev ] \end_layout \begin_layout Standard The following example shows one neighbor, which is a reachable router \end_layout \begin_layout Code # ip -6 neigh show \end_layout \begin_layout Code fe80::201:23ff:fe45:6789 dev eth0 lladdr 00:01:23:45:67:89 router nud reachable \end_layout \begin_layout Section Manipulating neighbors table using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset \end_layout \begin_layout Subsection Manually add an entry \end_layout \begin_layout Standard With following command you are able to manually add an entry \end_layout \begin_layout Code # ip -6 neigh add lladdr dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # ip -6 neigh add fec0::1 lladdr 02:01:02:03:04:05 dev eth0 \end_layout \begin_layout Subsection Manually delete an entry \end_layout \begin_layout Standard Like adding also an entry can be deleted: \end_layout \begin_layout Code # ip -6 neigh del lladdr dev \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # ip -6 neigh del fec0::1 lladdr 02:01:02:03:04:05 dev eth0 \end_layout \begin_layout Subsection More advanced settings \end_layout \begin_layout Standard The tool \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset is less documentated, but very strong. See online \begin_inset Quotes sld \end_inset help \begin_inset Quotes srd \end_inset for more: \end_layout \begin_layout Code # ip -6 neigh help \end_layout \begin_layout Code Usage: ip neigh { add | del | change | replace } { ADDR [ lladdr LLADDR ] \end_layout \begin_layout Code [ nud { permanent | noarp | stale | reachable } ] \end_layout \begin_layout Code | proxy ADDR } [ dev DEV ] \end_layout \begin_layout Code ip neigh {show|flush} [ to PREFIX ] [ dev DEV ] [ nud STATE ] \end_layout \begin_layout Standard Looks like some options are only for IPv4...if you can contribute information about flags and advanced usage, pls. send. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-configuring-ipv6-in-ipv4-tunnels" \end_inset Configuring IPv6-in-IPv4 tunnels \end_layout \begin_layout Standard \align left If you want to leave your link and you have no IPv6 capable network around you, you need IPv6-in-IPv4 tunneling to reach the world wide IPv6-Internet. \end_layout \begin_layout Standard \align left There are some kind of tunnel mechanism and also some possibilities to setup tunnels. \end_layout \begin_layout Section Types of tunnels \end_layout \begin_layout Standard There are more than one possibility to tunnel IPv6 packets over IPv4-only links. \end_layout \begin_layout Subsection Static point-to-point tunneling \end_layout \begin_layout Standard \align left A point-to-point tunnel is a dedicated tunnel to an endpoint, which knows about your IPv6 network (for backward routing) and the IPv4 address of your tunnel endpoint and defined in \begin_inset CommandInset href LatexCommand href name "RFC 4213 / Basic Transition Mechanisms for IPv6 Hosts and Routers" target "http://www.faqs.org/rfcs/rfc4213.html" \end_inset . Requirements: \end_layout \begin_layout Itemize \align left IPv4 address of your local tunnel endpoint must be static, global unique and reachable from the foreign tunnel endpoint \begin_inset Separator latexpar \end_inset \end_layout \begin_deeper \begin_layout Itemize If no static IPv4 address is available, the tunnel provider must support authentication of the dynamic IPv4 address, like \begin_inset CommandInset href LatexCommand href name "SixXS / AICCU" target "http://www.sixxs.net/" \end_inset (3740/udp) or \begin_inset CommandInset href LatexCommand href name "gogo6" target "http://gogo6.com/" \end_inset (3653/udp). \end_layout \end_deeper \begin_layout Itemize \align left A global IPv6 prefix assigned to you \begin_inset Separator latexpar \end_inset \end_layout \begin_deeper \begin_layout Itemize It is also possible that additional IPv6 networks are routed through this tunnel. \end_layout \end_deeper \begin_layout Itemize \align left A foreign tunnel endpoint which is capable to route your IPv6 prefix to your local tunnel endpoint (mostly remote manual configuration required) \end_layout \begin_layout Standard \lang ngerman Tunnel provider for static point-to-point tunneling: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Hurricane Electric" target "http://he.com/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SixXS" target "http://www.sixxs.net/" \end_inset \end_layout \begin_layout Subsection Automatically tunneling \end_layout \begin_layout Standard Automatic tunneling occurs, when a node directly connects another node gotten the IPv4 address of the other node before. \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "tunneling-6to4" \end_inset 6to4-Tunneling \end_layout \begin_layout Standard 6to4 tunneling ( \begin_inset CommandInset href LatexCommand href name "RFC 3056 / Connection of IPv6 Domains via IPv4 Clouds" target "http://www.faqs.org/rfcs/rfc3056.html" \end_inset ) uses a simple mechanism to create automatic tunnels. Each node with a global unique IPv4 address is able to be a 6to4 tunnel endpoint (if no IPv4 firewall prohibits traffic). 6to4 tunneling is mostly not a one-to-one tunnel. This case of tunneling can be divided into upstream and downstream tunneling. Also, a special IPv6 address indicates that this node will use 6to4 tunneling for connecting the world-wide IPv6 network \end_layout \begin_layout Subsubsection Generation of 6to4 prefix \end_layout \begin_layout Standard The 6to4 address is defined like following (schema is taken from \begin_inset CommandInset href LatexCommand href name "RFC 3056 / Connection of IPv6 Domains via IPv4 Clouds" target "http://www.faqs.org/rfcs/rfc3056.html" \end_inset ): \end_layout \begin_layout Code | 3+13 | 32 | 16 | 64 bits | \end_layout \begin_layout Code +---+------+-----------+--------+--------------------------------+ \end_layout \begin_layout Code | FP+TLA | V4ADDR | SLA ID | Interface ID | \end_layout \begin_layout Code | 0x2002 | | | | \end_layout \begin_layout Code +---+------+-----------+--------+--------------------------------+ \end_layout \begin_layout Standard FP and TLA together (16 bits) have the value 0x2002. V4ADDR is the node's global unique IPv4 address (in hexadecimal notation). SLA is the subnet identifier (65536 local subnets possible) and are usable to represent your local network structure. \end_layout \begin_layout Standard For gateways, such prefix is generated by normally using SLA \begin_inset Quotes sld \end_inset 0000 \begin_inset Quotes srd \end_inset and suffix \begin_inset Quotes sld \end_inset ::1 \begin_inset Quotes srd \end_inset (not a must, can be an arbitrary one with local-scope) and assigned to the 6to4 tunnel interface. Note that Microsoft Windows uses V4ADDR also for suffix. \end_layout \begin_layout Subsubsection 6to4 upstream tunneling \end_layout \begin_layout Standard The node has to know to which foreign tunnel endpoint its in IPv4 packed IPv6 packets should be send to. In \begin_inset Quotes sld \end_inset early \begin_inset Quotes srd \end_inset days of 6to4 tunneling, dedicated upstream accepting routers were defined. See \begin_inset CommandInset href LatexCommand href name "NSayer's 6to4 information" target "http://www.kfu.com/~nsayer/6to4/" \end_inset for a list of routers. \end_layout \begin_layout Standard Nowadays, 6to4 upstream routers can be found auto-magically using the anycast address 192.88.99.1. In the background routing protocols handle this, see \begin_inset CommandInset href LatexCommand href name "RFC 3068 / An Anycast Prefix for 6to4 Relay Routers" target "http://www.faqs.org/rfcs/rfc3068.html" \end_inset for details. \end_layout \begin_layout Subsubsection 6to4 downstream tunneling \end_layout \begin_layout Standard The downstream (IPv6 backbone -> your 6to4 enabled node) is not really fix and can vary from foreign host which originated packets were send to. There exist two possibilities: \end_layout \begin_layout Itemize Foreign host uses 6to4 and sends packet direct back to your node (see below) \end_layout \begin_layout Itemize Foreign host sends packets back to the world-wide IPv6 network and depending on the dynamic routing a relay router of an ISP which announces 2002::/16 via BGP will create a automatic tunnel back to your node. \end_layout \begin_layout Subsubsection Possible 6to4 traffic \end_layout \begin_layout Itemize from 6to4 to 6to4: is normally directly tunneled between the both 6to4 enabled hosts \end_layout \begin_layout Itemize from 6to4 to non-6to4: is sent via upstream tunneling \end_layout \begin_layout Itemize non-6to4 to 6to4: is sent via downstream tunneling \end_layout \begin_layout Standard \lang ngerman Note, that because of possible asymmetric routing problems with a broken 6to4 relay can be hard to troubleshoot. \end_layout \begin_layout Subsection UDP encapsulated IPv6 tunneling \end_layout \begin_layout Standard UDP encapsulated IPv6 tunneling is usally used if no global IPv4 address is available on the internal endpoint, but using Network Adress Translation (NAT) it can still reach related endpoints using UDP ports described below. \end_layout \begin_layout Subsubsection Teredo Tunnel \end_layout \begin_layout Standard \begin_inset CommandInset href LatexCommand href name "RFC 4380 / Teredo: Tunneling IPv6 over UDP through Network Address Translations" target "http://www.faqs.org/rfcs/rfc4380.html" \end_inset describes tunneling of IPv6 packets via IPv4 UDP bubbles, see also \begin_inset CommandInset href LatexCommand href name "Wikipedia / Teredo" target "http://de.wikipedia.org/wiki/Teredo" \end_inset . It uses usually 3544/udp. Linux client is named \begin_inset CommandInset href LatexCommand href name "miredo" target "http://www.remlab.net/miredo/" \end_inset and usable out-of-the-box. This tunnel method can only connect a single client to the global IPv6 network.. \end_layout \begin_layout Subsubsection AYIYA Tunnel \end_layout \begin_layout Standard Tunnel provider \begin_inset CommandInset href LatexCommand href name "SixXS" target "http://www.sixxs.net/" \end_inset has also IPv6-in-UDP-in-IPv4 (5072/udp) capability, for using it, the AYIYA mode must be enabled. \end_layout \begin_layout Subsubsection gogo6 Tunnel \end_layout \begin_layout Standard Tunnel provider \begin_inset CommandInset href LatexCommand href name "gogo6" target "http://gogo6.com/" \end_inset has also IPv6-in-UDP-in-IPv4 (3653/udp) capability, for using it, the v6udpv4 mode must be enabled. \end_layout \begin_layout Section Displaying existing tunnels \end_layout \begin_layout Subsection Using "ip" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 tunnel show [] \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 tunnel show \end_layout \begin_layout Code sit0: ipv6/ip remote any local any ttl 64 nopmtudisc \end_layout \begin_layout Code sit1: ipv6/ip remote 195.226.187.50 local any ttl 64 \end_layout \begin_layout Subsection Using "route" \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/route -A inet6 \end_layout \begin_layout Standard Example (output is filtered to display only tunnels through virtual interface sit0): \end_layout \begin_layout Code # /sbin/route -A inet6 | grep " \backslash Wsit0 \backslash W*$" \end_layout \begin_layout Code ::/96 :: U 256 2 0 sit0 \end_layout \begin_layout Code 2002::/16 :: UA 256 0 0 sit0 \end_layout \begin_layout Code 2000::/3 ::193.113.58.75 UG 1 0 0 sit0 \end_layout \begin_layout Code fe80::/10 :: UA 256 0 0 sit0 \end_layout \begin_layout Code ff00::/8 :: UA 256 0 0 sit0 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "conf-ipv6-in-ipv4-point-to-point-tunnels" \end_inset Setup of point-to-point tunnel \end_layout \begin_layout Standard \align left There are 3 possibilities to add or remove point-to-point tunnels. \end_layout \begin_layout Standard A good additional information about tunnel setup using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset is \begin_inset CommandInset href LatexCommand href name "Configuring tunnels with iproute2 (article)" target "http://www.deepspace6.net/docs/iproute2tunnel-en.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/docs/iproute2tunnel-en.html" \end_inset ). \end_layout \begin_layout Subsection Add point-to-point tunnels \end_layout \begin_layout Subsubsection Using "ip" \end_layout \begin_layout Standard \align left Common method at the moment for a small amount of tunnels. \end_layout \begin_layout Standard Usage for creating a tunnel device (but it's not up afterward, also a TTL must be specified because the default value is 0). \end_layout \begin_layout Code # /sbin/ip tunnel add mode sit ttl remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ip tunnel add sit1 mode sit ttl remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev sit1 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev sit1 metric 1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip tunnel add sit2 mode sit ttl \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev sit2 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev sit2 metric 1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip tunnel add sit3 mode sit ttl \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev sit3 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev sit3 metric 1 \end_layout \begin_layout Subsubsection Using "ifconfig" and "route" (deprecated) \end_layout \begin_layout Standard \align left This not very recommended way to add a tunnel because it's a little bit strange. No problem if adding only one, but if you setup more than one, you cannot easy shutdown the first ones and leave the others running. \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ifconfig sit0 up \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ifconfig sit0 tunnel \end_layout \begin_layout Code # /sbin/ifconfig sit1 up \end_layout \begin_layout Code # /sbin/route -A inet6 add dev sit1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ifconfig sit0 tunnel \end_layout \begin_layout Code # /sbin/ifconfig sit2 up \end_layout \begin_layout Code # /sbin/route -A inet6 add dev sit2 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ifconfig sit0 tunnel \end_layout \begin_layout Code # /sbin/ifconfig sit3 up \end_layout \begin_layout Code # /sbin/route -A inet6 add dev sit3 \end_layout \begin_layout Standard Important: DON'T USE THIS, because this setup implicit enable "automatic tunneling" from anywhere in the Internet, this is a risk, and it should not be advocated. \end_layout \begin_layout Subsubsection Using "route" only \end_layout \begin_layout Standard \align left It's also possible to setup tunnels in Non Broadcast Multiple Access (NBMA) style, it's a easy way to add many tunnels at once. But none of the tunnel can be numbered (which is a not required feature). \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ifconfig sit0 up \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/route -A inet6 add gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Code # /sbin/route -A inet6 add gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Code # /sbin/route -A inet6 add gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Standard Important: DON'T USE THIS, because this setup implicit enable "automatic tunneling" from anywhere in the Internet, this is a risk, and it should not be advocated. \end_layout \begin_layout Subsection Removing point-to-point tunnels \end_layout \begin_layout Standard \align left Manually not so often needed, but used by scripts for clean shutdown or restart of IPv6 configuration. \end_layout \begin_layout Subsubsection Using "ip" \end_layout \begin_layout Standard Usage for removing a tunnel device: \end_layout \begin_layout Code # /sbin/ip tunnel del \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ip -6 route del dev sit1 \end_layout \begin_layout Code # /sbin/ip link set sit1 down \end_layout \begin_layout Code # /sbin/ip tunnel del sit1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 route del dev sit2 \end_layout \begin_layout Code # /sbin/ip link set sit2 down \end_layout \begin_layout Code # /sbin/ip tunnel del sit2 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 route del dev sit3 \end_layout \begin_layout Code # /sbin/ip link set sit3 down \end_layout \begin_layout Code # /sbin/ip tunnel del sit3 \end_layout \begin_layout Subsubsection Using "ifconfig" and "route" (deprecated because not very funny) \end_layout \begin_layout Standard \align left Not only the creation is strange, the shutdown also...you have to remove the tunnels in backorder, means the latest created must be removed first. \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/route -A inet6 del dev sit3 \end_layout \begin_layout Code # /sbin/ifconfig sit3 down \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/route -A inet6 del dev sit2 \end_layout \begin_layout Code # /sbin/ifconfig sit2 down \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/route -A inet6 add dev sit1 \end_layout \begin_layout Code # /sbin/ifconfig sit1 down \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ifconfig sit0 down \end_layout \begin_layout Code \end_layout \begin_layout Subsubsection Using "route" \end_layout \begin_layout Standard This is like removing normal IPv6 routes. \begin_inset Separator latexpar \end_inset \end_layout \begin_layout Standard \align left Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/route -A inet6 del gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Code # /sbin/route -A inet6 del gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Code # /sbin/route -A inet6 del gw \end_layout \begin_layout Code ¬ :: dev sit0 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ifconfig sit0 down \end_layout \begin_layout Subsection Numbered point-to-point tunnels \end_layout \begin_layout Standard Sometimes it's needed to configure a point-to-point tunnel with IPv6 addresses like in IPv4 today. This is only possible with the first (ifconfig+route - deprecated) and third (ip+route) tunnel setup. In such cases, you can add the IPv6 address to the tunnel interface like shown on interface configuration. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "configuring-ipv6to4-tunnels" \end_inset Setup of 6to4 tunnels \end_layout \begin_layout Standard Pay attention that the support of 6to4 tunnels currently lacks on vanilla kernel series 2.2.x (see \begin_inset CommandInset ref LatexCommand ref name "systemcheck/kernel" reference "systemcheck-kernel" \end_inset for more information). Also note that that the prefix length for a 6to4 address is 16 because of from network point of view, all other 6to4 enabled hosts are on the same layer 2. \end_layout \begin_layout Subsection Add a 6to4 tunnel \end_layout \begin_layout Standard First, you have to calculate your 6to4 prefix using your local assigned global routable IPv4 address (if your host has no global routable IPv4 address, in special cases NAT on border gateways is possible): \end_layout \begin_layout Standard Assuming your IPv4 address is \end_layout \begin_layout Code 1.2.3.4 \end_layout \begin_layout Standard the generated 6to4 prefix will be \end_layout \begin_layout Code 2002:0102:0304:: \end_layout \begin_layout Standard Local 6to4 gateways should (but it's not a must, you can choose an arbitrary suffix with local-scope, if you feel better) always assigned the suffix \begin_inset Quotes sld \end_inset ::1 \begin_inset Quotes srd \end_inset , therefore your local 6to4 address will be \end_layout \begin_layout Code 2002:0102:0304::1 \end_layout \begin_layout Standard Use e.g. following for automatic generation: \end_layout \begin_layout Code ipv4="1.2.3.4"; printf "2002:%02x%02x:%02x%02x::1" `echo $ipv4 | tr "." " "` \end_layout \begin_layout Standard There are two ways possible to setup 6to4 tunneling now. \end_layout \begin_layout Subsubsection Using "ip" and a dedicated tunnel device \end_layout \begin_layout Standard This is now the recommended way (a TTL must be specified because the default value is 0). \end_layout \begin_layout Standard Create a new tunnel device \end_layout \begin_layout Code # /sbin/ip tunnel add tun6to4 mode sit ttl remote any local \end_layout \begin_layout Code ¬ \end_layout \begin_layout Standard Bring interface up \end_layout \begin_layout Code # /sbin/ip link set dev tun6to4 up \end_layout \begin_layout Standard Add local 6to4 address to interface (note: prefix length 16 is important!) \end_layout \begin_layout Code # /sbin/ip -6 addr add /16 dev tun6to4 \end_layout \begin_layout Standard Add (default) route to the global IPv6 network using the all-6to4-routers IPv4 anycast address \end_layout \begin_layout Code # /sbin/ip -6 route add default via ::192.88.99.1 dev tun6to4 metric 1 \end_layout \begin_layout Standard It was reported that some versions of \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset (e.g. SuSE Linux 9.0) don't support IPv4-compatible IPv6 addresses for gateways, in this case the related IPv6 address has to be used: \end_layout \begin_layout Code # /sbin/ip -6 route add default via 2002:c058:6301::1 dev tun6to4 metric 1 \end_layout \begin_layout Subsubsection Using "ifconfig" and "route" and generic tunnel device \begin_inset Quotes sld \end_inset sit0 \begin_inset Quotes srd \end_inset (deprecated) \end_layout \begin_layout Standard This is now deprecated because using the generic tunnel device sit0 doesn't let specify filtering per device. \end_layout \begin_layout Standard Bring generic tunnel interface sit0 up \end_layout \begin_layout Code # /sbin/ifconfig sit0 up \end_layout \begin_layout Standard Add local 6to4 address to interface \end_layout \begin_layout Code # /sbin/ifconfig sit0 add /16 \end_layout \begin_layout Standard Add (default) route to the global IPv6 network using the all-6to4-relays IPv4 anycast address \end_layout \begin_layout Code # /sbin/route -A inet6 add default gw ::192.88.99.1 dev sit0 \end_layout \begin_layout Subsection Remove a 6to4 tunnel \end_layout \begin_layout Subsubsection Using "ip" and a dedicated tunnel device \end_layout \begin_layout Standard Remove all routes through this dedicated tunnel device \end_layout \begin_layout Code # /sbin/ip -6 route flush dev tun6to4 \end_layout \begin_layout Standard Shut down interface \end_layout \begin_layout Code # /sbin/ip link set dev tun6to4 down \end_layout \begin_layout Standard Remove created tunnel device \end_layout \begin_layout Code # /sbin/ip tunnel del tun6to4 \end_layout \begin_layout Subsubsection Using \begin_inset Quotes sld \end_inset ifconfig \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset route \begin_inset Quotes srd \end_inset and generic tunnel device \begin_inset Quotes sld \end_inset sit0 \begin_inset Quotes srd \end_inset (deprecated) \end_layout \begin_layout Standard Remove (default) route through the 6to4 tunnel interface \end_layout \begin_layout Code # /sbin/route -A inet6 del default gw ::192.88.99.1 dev sit0 \end_layout \begin_layout Standard Remove local 6to4 address to interface \end_layout \begin_layout Code # /sbin/ifconfig sit0 del /16 \end_layout \begin_layout Standard Shut down generic tunnel device (take care about this, perhaps it's still in use...) \end_layout \begin_layout Code # /sbin/ifconfig sit0 down \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-configuring-ipv4-in-ipv6-tunnels" \end_inset Configuring IPv4-in-IPv6 tunnels \end_layout \begin_layout Standard \begin_inset CommandInset href LatexCommand href name "RFC 2473 / Generic Packet Tunneling in IPv6 Specification" target "http://www.faqs.org/rfcs/rfc2473.html" \end_inset specifies mechanisms to tunnel several different packet types over IPv6 including IPv4. \end_layout \begin_layout Standard NOTE: Support for IPv4-in-IPv6 tunnel is available only since kernel version 2.6.22. \end_layout \begin_layout Section Displaying existing tunnels \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Code # /sbin/ip -6 tunnel show [] \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # /sbin/ip -6 tunnel show mode any \end_layout \begin_layout Code ip6tnl0: ipv6/ipv6 remote :: local :: encaplimit 0 hoplimit 0 tclass 0x00 \end_layout \begin_layout Code ¬ flowlabel 0x00000 (flowinfo 0x00000000) \end_layout \begin_layout Code ip6tnl1: ip/ipv6 remote fd00:0:0:2::a local fd00:0:0:2::1 dev eth1 encaplimit 4 \end_layout \begin_layout Code ¬ hoplimit 64 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000) \end_layout \begin_layout Standard NOTE: If you don't include "mode any", only IPv6-in-IPv6 tunnels are displayed. \end_layout \begin_layout Section Setup of point-to-point tunnel \end_layout \begin_layout Standard Usage for creating a 4over6 tunnel device (but it's not up afterward) \end_layout \begin_layout Code # /sbin/ip tunnel add mode ip4ip6 remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ip -6 tunnel add ip6tnl1 mode ip4ip6 remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev ip6tnl1 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev ip6tnl1 metric 1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 tunnel add ip6tnl2 mode ip4ip6 remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev ip6tnl2 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev ip6tnl2 metric 1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 tunnel add ip6tnl3 mode ip4ip6 remote \end_layout \begin_layout Code ¬ local \end_layout \begin_layout Code # /sbin/ip link set dev ip6tnl3 up \end_layout \begin_layout Code # /sbin/ip -6 route add dev ip6tnl3 metric 1 \end_layout \begin_layout Section Removing point-to-point tunnels \end_layout \begin_layout Standard Usage for removing a tunnel device: \end_layout \begin_layout Code # /sbin/ip -6 tunnel del \end_layout \begin_layout Standard Usage (generic example for three tunnels): \end_layout \begin_layout Code # /sbin/ip -6 route del dev ip6tnl1 \end_layout \begin_layout Code # /sbin/ip link set ip6tnl1 down \end_layout \begin_layout Code # /sbin/ip -6 tunnel del ip6tnl1 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 route del dev ip6tnl2 \end_layout \begin_layout Code # /sbin/ip link set ip6tnl2 down \end_layout \begin_layout Code # /sbin/ip -6 tunnel del ip6tnl2 \end_layout \begin_layout Code \end_layout \begin_layout Code # /sbin/ip -6 route del dev ip6tnl3 \end_layout \begin_layout Code # /sbin/ip link set ip6tnl3 down \end_layout \begin_layout Code # /sbin/ip -6 tunnel del ip6tnl3 \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-kernel-settings" \end_inset Kernel settings in /proc-filesystem \end_layout \begin_layout Standard \begin_inset CommandInset label LatexCommand label name "proc-filesystem" \end_inset Note: the source of this section is mostly the file \begin_inset Quotes sld \end_inset ip-sysctl.txt \begin_inset Quotes srd \end_inset which is included in current kernel sources in directory \begin_inset Quotes sld \end_inset Documentation/networking \begin_inset Quotes srd \end_inset . Credits to Pekka Savola for maintaining the IPv6-related part in this file. Also some text is more or less copied & pasted into this document. \end_layout \begin_layout Section How to access the /proc-filesystem \end_layout \begin_layout Subsection Using \begin_inset Quotes sld \end_inset cat \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset echo \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard Using \begin_inset Quotes sld \end_inset cat \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset echo \begin_inset Quotes srd \end_inset is the simplest way to access the /proc filesystem, but some requirements are needed for that \end_layout \begin_layout Itemize The /proc-filesystem had to be enabled in kernel, means on compiling following switch has to be set \end_layout \begin_layout Code CONFIG_PROC_FS=y \end_layout \begin_layout Itemize The /proc-filesystem was mounted before, which can be tested using \end_layout \begin_layout Code # mount | grep "type proc" \end_layout \begin_layout Code none on /proc type proc (rw) \end_layout \begin_layout Itemize You need read and sometimes also write access (normally root only) to the /proc-filesystem \end_layout \begin_layout Standard Normally, only entries in /proc/sys/* are writable, the others are readonly and for information retrieving only. \end_layout \begin_layout Subsubsection Retrieving a value \end_layout \begin_layout Standard The value of an entry can be retrieved using \begin_inset Quotes sld \end_inset cat \begin_inset Quotes srd \end_inset : \end_layout \begin_layout Code # cat /proc/sys/net/ipv6/conf/all/forwarding \end_layout \begin_layout Code 0 \end_layout \begin_layout Subsubsection Setting a value \end_layout \begin_layout Standard A new value can be set (if entry is writable) using \begin_inset Quotes sld \end_inset echo \begin_inset Quotes srd \end_inset : \end_layout \begin_layout Code # echo "1" >/proc/sys/net/ipv6/conf/all/forwarding \end_layout \begin_layout Subsection Using \begin_inset Quotes sld \end_inset sysctl \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard Using the \begin_inset Quotes sld \end_inset sysctl \begin_inset Quotes srd \end_inset program to access the kernel switches is a modern method today. You can use it also, if the /proc-filesystem isn't mounted. But you have only access to /proc/sys/*! \end_layout \begin_layout Standard The program \begin_inset Quotes sld \end_inset sysctl \begin_inset Quotes srd \end_inset is included in package \begin_inset Quotes sld \end_inset procps \begin_inset Quotes srd \end_inset (on Red Hat Linux systems). \end_layout \begin_layout Itemize The sysctl-interface had to be enabled in kernel, means on compiling following switch has to be set \end_layout \begin_layout Code CONFIG_SYSCTL=y \end_layout \begin_layout Subsubsection Retrieving a value \end_layout \begin_layout Standard The value of an entry can be retrieved now: \end_layout \begin_layout Code # sysctl net.ipv6.conf.all.forwarding \end_layout \begin_layout Code net.ipv6.conf.all.forwarding = 0 \end_layout \begin_layout Subsubsection Setting a value \end_layout \begin_layout Standard A new value can be set (if entry is writable): \end_layout \begin_layout Code # sysctl -w net.ipv6.conf.all.forwarding=1 \end_layout \begin_layout Code net.ipv6.conf.all.forwarding = 1 \end_layout \begin_layout Standard Note: Don't use spaces around the \begin_inset Quotes sld \end_inset = \begin_inset Quotes srd \end_inset on setting values. Also on multiple values per line, quote them like e.g. \end_layout \begin_layout Code # sysctl -w net.ipv4.ip_local_port_range="32768 61000" \end_layout \begin_layout Code net.ipv4.ip_local_port_range = 32768 61000 \end_layout \begin_layout Subsubsection Additionals \end_layout \begin_layout Standard Note: There are sysctl versions in the wild which displaying \begin_inset Quotes sld \end_inset / \begin_inset Quotes srd \end_inset instead of the \begin_inset Quotes sld \end_inset . \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard For more details take a look into sysctl's manpage. \end_layout \begin_layout Standard Hint: for digging fast into the settings, use the option \begin_inset Quotes sld \end_inset -a \begin_inset Quotes srd \end_inset (display all entries) in conjunction with \begin_inset Quotes sld \end_inset grep \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsection Values found in /proc-filesystems \end_layout \begin_layout Standard There are several formats seen in /proc-filesystem: \end_layout \begin_layout Itemize BOOLEAN: simple a \begin_inset Quotes sld \end_inset 0 \begin_inset Quotes srd \end_inset (false) or a \begin_inset Quotes sld \end_inset 1 \begin_inset Quotes srd \end_inset (true) \end_layout \begin_layout Itemize INTEGER: an integer value, can be unsigned, too \end_layout \begin_layout Itemize more sophisticated lines with several values: sometimes a header line is displayed also, if not, have a look into the kernel source to retrieve information about the meaning of each value... \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "proc-sys-net-ipv6" \end_inset Entries in /proc/sys/net/ipv6/ \end_layout \begin_layout Subsection conf/default/* \end_layout \begin_layout Standard Change the interface-specific default settings. \end_layout \begin_layout Subsection conf/all/* \end_layout \begin_layout Standard Change all the interface-specific settings. \end_layout \begin_layout Standard Exception: \begin_inset Quotes sld \end_inset conf/all/forwarding \begin_inset Quotes srd \end_inset has a different meaning here \end_layout \begin_layout Subsubsection conf/all/forwarding \end_layout \begin_layout Itemize Type: BOOLEAN \end_layout \begin_layout Standard This enables global IPv6 forwarding between all interfaces. \end_layout \begin_layout Standard In IPv6 you can't control forwarding per device, forwarding control has to be done using IPv6-netfilter (controlled with ip6tables) rulesets and specify input and output devices (see \begin_inset CommandInset ref LatexCommand ref name "Firewalling/Netfilter6" reference "firewalling-netfilter6" \end_inset for more). This is different to IPv4, where you are able to control forwarding per device (decision is made on interface where packet came in). \end_layout \begin_layout Standard This also sets all interfaces' Host/Router setting 'forwarding' to the specified value. See below for details. This referred to as global forwarding. \end_layout \begin_layout Standard If this value is 0, no IPv6 forwarding is enabled, packets never leave another interface, neither physical nor logical like e.g. tunnels. \end_layout \begin_layout Subsection conf/interface/* \end_layout \begin_layout Standard Change special settings per interface. \end_layout \begin_layout Standard The functional behaviour for certain settings is different depending on whether local forwarding is enabled or not. \end_layout \begin_layout Subsubsection accept_ra \end_layout \begin_layout Itemize Type: BOOLEAN \end_layout \begin_layout Itemize Functional default: enabled if local forwarding is disabled. disabled if local forwarding is enabled. \end_layout \begin_layout Standard Accept Router Advertisements, and autoconfigure this interface with received data. \end_layout \begin_layout Subsubsection accept_redirects \end_layout \begin_layout Itemize Type: BOOLEAN \end_layout \begin_layout Itemize Functional default: enabled if local forwarding is disabled. disabled if local forwarding is enabled. \end_layout \begin_layout Standard Accept Redirects sent by an IPv6 router. \end_layout \begin_layout Subsubsection autoconf \end_layout \begin_layout Itemize Type: BOOLEAN \end_layout \begin_layout Itemize Functional default: enabled if accept_ra_pinfo is enabled. disabled if accept_ra_pinfo is disabled. \end_layout \begin_layout Standard Autoconfigure addresses using prefix information from router advertisements. \end_layout \begin_layout Subsubsection dad_transmits \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 1 \end_layout \begin_layout Standard The amount of Duplicate Address Detection probes to send. \end_layout \begin_layout Subsubsection forwarding \end_layout \begin_layout Itemize Type: BOOLEAN \end_layout \begin_layout Itemize Default: FALSE if global forwarding is disabled (default), otherwise TRUE \end_layout \begin_layout Standard Configure interface-specific Host/Router behaviour. \end_layout \begin_layout Standard Note: It is recommended to have the same setting on all interfaces; mixed router/host scenarios are rather uncommon. \end_layout \begin_layout Itemize Value FALSE: By default, Host behaviour is assumed. This means: \end_layout \begin_layout Enumerate IsRouter flag is not set in Neighbour Advertisements. \end_layout \begin_layout Enumerate Router Solicitations are being sent when necessary. \end_layout \begin_layout Enumerate If accept_ra is TRUE (default), accept Router Advertisements (and do autoconfigu ration). \end_layout \begin_layout Enumerate If accept_redirects is TRUE (default), accept Redirects. \end_layout \begin_layout Itemize Value TRUE: If local forwarding is enabled, Router behaviour is assumed. This means exactly the reverse from the above: \end_layout \begin_layout Enumerate IsRouter flag is set in Neighbour Advertisements. \end_layout \begin_layout Enumerate Router Solicitations are not sent. \end_layout \begin_layout Enumerate Router Advertisements are ignored. \end_layout \begin_layout Enumerate Redirects are ignored. \end_layout \begin_layout Subsubsection hop_limit \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 64 \end_layout \begin_layout Standard Default Hop Limit to set. \end_layout \begin_layout Subsubsection mtu \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 1280 (IPv6 required minimum) \end_layout \begin_layout Standard Default Maximum Transfer Unit \end_layout \begin_layout Subsubsection router_solicitation_delay \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 1 \end_layout \begin_layout Standard Number of seconds to wait after interface is brought up before sending Router Solicitations. \end_layout \begin_layout Subsubsection router_solicitation_interval \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 4 \end_layout \begin_layout Standard Number of seconds to wait between Router Solicitations. \end_layout \begin_layout Subsubsection router_solicitations \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 3 \end_layout \begin_layout Standard Number of Router Solicitations to send until assuming no routers are present. \end_layout \begin_layout Subsection neigh/default/* \end_layout \begin_layout Standard Change default settings for neighbor detection and some special global interval and threshold values: \end_layout \begin_layout Subsubsection gc_thresh1 \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 128 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_thresh2 \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 512 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_thresh3 \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 1024 \end_layout \begin_layout Standard Tuning parameter for neighbour table size. \end_layout \begin_layout Standard Increase this value if you have a lot of interfaces and problem with routes start to act mysteriously and fail. Or if a running \begin_inset CommandInset href LatexCommand href name "Zebra (routing daemon)" target "http://www.zebra.org/" \end_inset reports: \end_layout \begin_layout Code ZEBRA: netlink-listen error: No buffer space available, type=RTM_NEWROUTE(24), \end_layout \begin_layout Code ¬ seq=426, pid=0 \end_layout \begin_layout Subsubsection gc_interval \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 30 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsection neigh/interface/* \end_layout \begin_layout Standard Change special settings per interface for neighbor detection. \end_layout \begin_layout Subsubsection anycast_delay \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 100 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_stale_time \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 60 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection proxy_qlen \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 64 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection unres_qlen \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 3 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection app_solicit \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 0 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection locktime \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 0 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection retrans_time \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 100 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection base_reachable_time \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 30 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection mcast_solicit \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 3 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection ucast_solicit \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 3 \end_layout \begin_layout Standard More to be filled \end_layout \begin_layout Subsubsection delay_first_probe_time \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 5 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection proxy_delay \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 80 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsection route/* \end_layout \begin_layout Standard Change global settings for routing. \end_layout \begin_layout Subsubsection flush \end_layout \begin_layout Standard Removed in newer kernel releases - more to be filled. \end_layout \begin_layout Subsubsection gc_interval \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 30 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_thresh \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 1024 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection mtu_expires \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 600 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_elasticity \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 0 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_min_interval \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 5 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection gc_timeout \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 60 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection min_adv_mss \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 12 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Subsubsection max_size \end_layout \begin_layout Itemize Type: INTEGER \end_layout \begin_layout Itemize Default: 4096 \end_layout \begin_layout Standard More to be filled. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "proc-sys-net-ipv4" \end_inset IPv6-related entries in /proc/sys/net/ipv4/ \end_layout \begin_layout Standard At the moment (and this will be until IPv4 is completly converted to an independend kernel module) some switches are also used here for IPv6. \end_layout \begin_layout Subsection ip_* \end_layout \begin_layout Subsubsection ip_local_port_range \end_layout \begin_layout Standard This control setting is used by IPv6 also. \end_layout \begin_layout Subsection tcp_* \end_layout \begin_layout Standard This control settings are used by IPv6 also. \end_layout \begin_layout Subsection icmp_* \end_layout \begin_layout Standard This control settings are not used by IPv6. To enable ICMPv6 rate limiting (which is very recommended because of the capability of ICMPv6 storms) netfilter-v6 rules must be used. \end_layout \begin_layout Subsection others \end_layout \begin_layout Standard Unknown, but probably not used by IPv6. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "proc-net" \end_inset IPv6-related entries in /proc/net/ \end_layout \begin_layout Standard In /proc/net there are several read-only entries available. You cannot retrieve information using \begin_inset Quotes sld \end_inset sysctl \begin_inset Quotes srd \end_inset here, so use e.g. \begin_inset Quotes sld \end_inset cat \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsection if_inet6 \end_layout \begin_layout Itemize Type: One line per addresss containing multiple values \end_layout \begin_layout Standard Here all configured IPv6 addresses are shown in a special format. The example displays for loopback interface only. The meaning is shown below (see \begin_inset Quotes sld \end_inset net/ipv6/addrconf.c \begin_inset Quotes srd \end_inset for more). \end_layout \begin_layout Code # cat /proc/net/if_inet6 \end_layout \begin_layout Code 00000000000000000000000000000001 01 80 10 80 lo \end_layout \begin_layout Code +------------------------------+ ++ ++ ++ ++ ++ \end_layout \begin_layout Code | | | | | | \end_layout \begin_layout Code 1 2 3 4 5 6 \end_layout \begin_layout Enumerate IPv6 address displayed in 32 hexadecimal chars without colons as separator \end_layout \begin_layout Enumerate Netlink device number (interface index) in hexadecimal (see \begin_inset Quotes sld \end_inset ip addr \begin_inset Quotes srd \end_inset , too) \end_layout \begin_layout Enumerate Prefix length in hexadecimal \end_layout \begin_layout Enumerate Scope value (see kernel source \begin_inset Quotes sld \end_inset include/net/ipv6.h \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset net/ipv6/addrconf.c \begin_inset Quotes srd \end_inset for more) \end_layout \begin_layout Enumerate Interface flags (see \begin_inset Quotes sld \end_inset include/linux/rtnetlink.h \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset net/ipv6/addrconf.c \begin_inset Quotes srd \end_inset for more) \end_layout \begin_layout Enumerate Device name \end_layout \begin_layout Subsection ipv6_route \end_layout \begin_layout Itemize Type: One line per route containing multiple values \end_layout \begin_layout Standard Here all configured IPv6 routes are shown in a special format. The example displays for loopback interface only. The meaning is shown below (see \begin_inset Quotes sld \end_inset net/ipv6/route.c \begin_inset Quotes srd \end_inset for more). \end_layout \begin_layout Code # cat /proc/net/ipv6_route \end_layout \begin_layout Code 00000000000000000000000000000000 00 00000000000000000000000000000000 00 \end_layout \begin_layout Code +------------------------------+ ++ +------------------------------+ ++ \end_layout \begin_layout Code | | | | \end_layout \begin_layout Code 1 2 3 4 \end_layout \begin_layout Code \end_layout \begin_layout Code ¬ 00000000000000000000000000000000 ffffffff 00000001 00000001 00200200 lo \end_layout \begin_layout Code ¬ +------------------------------+ +------+ +------+ +------+ +------+ ++ \end_layout \begin_layout Code ¬ | | | | | | \end_layout \begin_layout Code ¬ 5 6 7 8 9 10 \end_layout \begin_layout Enumerate IPv6 destination network displayed in 32 hexadecimal chars without colons as separator \end_layout \begin_layout Enumerate IPv6 destination prefix length in hexadecimal \end_layout \begin_layout Enumerate IPv6 source network displayed in 32 hexadecimal chars without colons as separator \end_layout \begin_layout Enumerate IPv6 source prefix length in hexadecimal \end_layout \begin_layout Enumerate IPv6 next hop displayed in 32 hexadecimal chars without colons as separator \end_layout \begin_layout Enumerate Metric in hexadecimal \end_layout \begin_layout Enumerate Reference counter \end_layout \begin_layout Enumerate Use counter \end_layout \begin_layout Enumerate Flags \end_layout \begin_layout Enumerate Device name \end_layout \begin_layout Subsection sockstat6 \end_layout \begin_layout Itemize Type: One line per protocol with description and value \end_layout \begin_layout Standard Statistics about used IPv6 sockets. Example: \end_layout \begin_layout Code # cat /proc/net/sockstat6 \end_layout \begin_layout Code TCP6: inuse 7 \end_layout \begin_layout Code UDP6: inuse 2 \end_layout \begin_layout Code RAW6: inuse 1 \end_layout \begin_layout Code FRAG6: inuse 0 memory 0 \end_layout \begin_layout Subsection tcp6 \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection udp6 \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection igmp6 \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection raw6 \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection ip6_flowlabel \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection rt6_stats \end_layout \begin_layout Standard To be filled. \end_layout \begin_layout Subsection snmp6 \end_layout \begin_layout Itemize Type: One line per SNMP description and value \end_layout \begin_layout Standard SNMP statistics, can be retrieved via SNMP server and related MIB table by network management software. \end_layout \begin_layout Subsection ip6_tables_names \end_layout \begin_layout Standard Available netfilter6 tables \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "netlink" \end_inset Netlink-Interface to kernel \end_layout \begin_layout Standard To be filled...I have no experience with that... \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "resolver" \end_inset Address Resolver & Selection \end_layout \begin_layout Standard Additional info can be found at \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Linux & IPv6: getaddrinfo and search domains - Research" target "http://www.bieringer.de/linux/IPv6/getaddrinfo/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3484 on Linux" target "http://people.redhat.com/drepper/linux-rfc3484.html" \end_inset \end_layout \begin_layout Itemize Karl Auer's Blog: \begin_inset CommandInset href LatexCommand href name "Controlling IPv6 source address selection" target "http://biplane.com.au/blog/?p=30" \end_inset , \begin_inset CommandInset href LatexCommand href name "IPv6 Source Address Selection - what, why, how" target "http://biplane.com.au/blog/?p=22" \end_inset \end_layout \begin_layout Itemize Into6: \begin_inset CommandInset href LatexCommand href name "/etc/gai.conf - it ain't what you think it is" target "http://into6.com.au/?p=288" \end_inset \end_layout \begin_layout Section* Address Resolver & Destination Address Selection \end_layout \begin_layout Standard Name to IPv4 or IPv6 address resolving is usually done using a libc resolver library. Usually the function \emph on getaddrinfo \emph default is used for that. In case of more than one IPv6 address is returned, according to \begin_inset CommandInset href LatexCommand href name "RFC 3484 / Default Address Selection for Internet Protocol version 6" target "http://www.faqs.org/rfcs/rfc3484.html" \end_inset a sorting should be applied, which can be optionally configured. \end_layout \begin_layout Standard The \begin_inset Quotes sld \end_inset magic \begin_inset Quotes srd \end_inset is controlled by a file named /etc/gai.conf (it can be that it is empty or missing by default). Default is usually somewhere stored in documentation, see \begin_inset Quotes sld \end_inset man gai.conf \begin_inset Quotes srd \end_inset or e.g. /usr/share/doc/glibc-common/gai.conf. \end_layout \begin_layout Standard For controlling sort order by configuration following are needed for testing: \end_layout \begin_layout Itemize A host in DNS returning more than one IPv6 address, e.g. \end_layout \begin_layout Code $ dig +short aaaa st1.bieringer.de \end_layout \begin_layout Code 2001:4dd0:ff00:834::2 \end_layout \begin_layout Code 2a01:238:423d:8800:85b3:9e6b:3019:8909 \end_layout \begin_layout Itemize Lookup via DNS (/etc/hosts won't work) \end_layout \begin_layout Itemize /etc/gai.conf with proper config, e.g. \end_layout \begin_layout Code precedence ::1/128 50 # default \end_layout \begin_layout Code precedence ::/0 40 # default \end_layout \begin_layout Code precedence 2002::/16 30 # default \end_layout \begin_layout Code precedence ::/96 20 # default \end_layout \begin_layout Code precedence ::ffff:0:0/96 10 # default \end_layout \begin_layout Code precedence 2001:4dd0:ff00:834::/64 80 # dst-A \end_layout \begin_layout Code precedence 2a01:238:423d:8800::/64 90 # dst-B \end_layout \begin_layout Itemize For tests use e.g. telnet client \end_layout \begin_layout Code $ telnet st1.bieringer.de \end_layout \begin_layout Code Trying 2a01:238:423d:8800:85b3:9e6b:3019:8909... (dst-B) \end_layout \begin_layout Code ... \end_layout \begin_layout Code Trying 2001:4dd0:ff00:834::2... (dst-A) \end_layout \begin_layout Code ... \end_layout \begin_layout Itemize If precedence is changed in configuration \end_layout \begin_layout Code precedence 2001:4dd0:ff00:834::/64 90 # dst-A ex 80 \end_layout \begin_layout Code precedence 2a01:238:423d:8800::/64 80 # dst-B ex 90 \end_layout \begin_layout Itemize The order is changed accordingly \end_layout \begin_layout Code $ telnet st1.bieringer.de \end_layout \begin_layout Code Trying 2001:4dd0:ff00:834::2... (dst-A) \end_layout \begin_layout Code ... \end_layout \begin_layout Code Trying 2a01:238:423d:8800:85b3:9e6b:3019:8909... (dst-B) \end_layout \begin_layout Code ... \end_layout \begin_layout Section* Source Address Selection \end_layout \begin_layout Standard Source address selection in Linux is done automatically by kernel and usually only using information from routing tables and try to match the same scope of address. \end_layout \begin_layout Subsection* Source Address Selection with \begin_inset Quotes sld \end_inset ip addrlabel \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard With extension of internal \begin_inset Quotes sld \end_inset ip addrlabel \begin_inset Quotes srd \end_inset a source address can be bound to a destination address (e.g. selected via mechanisms above). Binding means here: \begin_inset Quotes sld \end_inset same label \begin_inset Quotes srd \end_inset (label is a number). \end_layout \begin_layout Itemize Default of \begin_inset Quotes sld \end_inset ip addrlabel \begin_inset Quotes srd \end_inset (here on CentOS 6): \end_layout \begin_layout Code # ip addrlabel \end_layout \begin_layout Code prefix ::1/128 label 0 \end_layout \begin_layout Code prefix ::/96 label 3 \end_layout \begin_layout Code prefix ::ffff:0.0.0.0/96 label 4 \end_layout \begin_layout Code prefix 2001::/32 label 6 \end_layout \begin_layout Code prefix 2001:10::/28 label 7 \end_layout \begin_layout Code prefix 2002::/16 label 2 \end_layout \begin_layout Code prefix fc00::/7 label 5 \end_layout \begin_layout Code prefix ::/0 label 1 \end_layout \begin_layout Itemize System is multihomed (here on one interface), router provides 2 prefixes via radvd: \end_layout \begin_layout Code # ip -6 addr show dev eth1 | grep -w inet6 |grep -w global \end_layout \begin_layout Code inet6 2001:6f8:12d8:2:5054:ff:fefb:6582/64 scope global dynamic \end_layout \begin_layout Code inet6 2001:6f8:900:8cbc:5054:ff:fefb:6582/64 scope global dynamic \end_layout \begin_layout Itemize Connect now to server (shown above) \end_layout \begin_layout Code $ telnet st1.bieringer.de \end_layout \begin_layout Code Trying 2001:4dd0:ff00:834::2... (dst-A) \end_layout \begin_layout Code ... \end_layout \begin_layout Code Trying 2a01:238:423d:8800:85b3:9e6b:3019:8909... (dst-B) \end_layout \begin_layout Code ... \end_layout \begin_layout Itemize Related tcpdump with filter \begin_inset Quotes sld \end_inset tcp and dst port 23 \begin_inset Quotes srd \end_inset shows only the use of the upper local source IPv6 address \end_layout \begin_layout Code IP6 2001:6f8:12d8:2:5054:ff:fefb:6582.37762 > 2001:4dd0:ff00:834::2.telnet: (src-A -> dst-A) \end_layout \begin_layout Code IP6 2001:6f8:12d8:2:5054:ff:fefb:6582.45754 > 2a01:238:423d:8800:85b3:9e6b:3019:8 909.telnet: (src-A -> dst-B) \end_layout \begin_layout Itemize Binding now source and destination with \begin_inset Quotes sld \end_inset ip addrlabel \begin_inset Quotes srd \end_inset \end_layout \begin_layout Code # ip addrlabel add prefix 2001:6f8:12d8:2::/64 label 200 \end_layout \begin_layout Code # ip addrlabel add prefix 2001:6f8:900:8cbc::/64 label 300 \end_layout \begin_layout Code # ip addrlabel add prefix 2001:4dd0:ff00:834::/64 label 200 \end_layout \begin_layout Code # ip addrlabel add prefix 2a01:238:423d:8800::/64 label 300 \end_layout \begin_layout Itemize Resulting \begin_inset Quotes sld \end_inset ip addrlabel \begin_inset Quotes srd \end_inset \end_layout \begin_layout Code # ip addrlabel \end_layout \begin_layout Code prefix ::1/128 label 0 \end_layout \begin_layout Code prefix ::/96 label 3 \end_layout \begin_layout Code prefix ::ffff:0.0.0.0/96 label 4 \end_layout \begin_layout Code prefix 2a01:238:423d:8800::/64 label 300 # dst-B \end_layout \begin_layout Code prefix 2001:4dd0:ff00:834::/64 label 200 # dst-A \end_layout \begin_layout Code prefix 2001:6f8:900:8cbc::/64 label 300 # src-B \end_layout \begin_layout Code prefix 2001:6f8:12d8:2::/64 label 200 # src-A \end_layout \begin_layout Code prefix 2001::/32 label 6 \end_layout \begin_layout Code prefix 2001:10::/28 label 7 \end_layout \begin_layout Code prefix 2002::/16 label 2 \end_layout \begin_layout Code prefix fc00::/7 label 5 \end_layout \begin_layout Code prefix ::/0 label 1 \end_layout \begin_layout Itemize Connect now to server again \end_layout \begin_layout Code $ telnet st1.bieringer.de \end_layout \begin_layout Code Trying 2001:4dd0:ff00:834::2... (dst-A) \end_layout \begin_layout Code ... \end_layout \begin_layout Code Trying 2a01:238:423d:8800:85b3:9e6b:3019:8909... (dst-B) \end_layout \begin_layout Code ... \end_layout \begin_layout Itemize Related tcpdump with filter \begin_inset Quotes sld \end_inset tcp and dst port 23 \begin_inset Quotes srd \end_inset shows now the use of both local source IPv6 addresses according to the configured pairs A and B \end_layout \begin_layout Code IP6 2001:6f8:12d8:2:5054:ff:fefb:6582.37765 > 2001:4dd0:ff00:834::2.telnet: (src-A -> dst-A) \end_layout \begin_layout Code IP6 2001:6f8:900:8cbc:5054:ff:fefb:6582.39632 > 2a01:238:423d:8800:85b3:9e6b:3019 :8909.telnet: (src-B -> dst-B) \end_layout \begin_layout Standard Setup of persistent \begin_inset Quotes sld \end_inset ip addrtable \begin_inset Quotes srd \end_inset is probably currently not supported by Linux distributions, so extension of network init scripts or rc.local must be used for that. A script which uses information from /etc/gai.conf and configure \begin_inset Quotes sld \end_inset ip addrtable \begin_inset Quotes srd \end_inset accordingly can be found here: \begin_inset CommandInset href LatexCommand href name "/etc/gai.conf - it ain't what you think it is" target "http://into6.com.au/?p=288" \end_inset \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "network-debugging" \end_inset Network debugging \end_layout \begin_layout Section Server socket binding \end_layout \begin_layout Subsection Using \begin_inset Quotes sld \end_inset netstat \begin_inset Quotes srd \end_inset for server socket binding check \end_layout \begin_layout Standard It's always interesting which server sockets are currently active on a node. Using \begin_inset Quotes sld \end_inset netstat \begin_inset Quotes srd \end_inset is a short way to get such information: \end_layout \begin_layout Standard Used options: -nlptu \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # netstat -nlptu \end_layout \begin_layout Code Active Internet connections (only servers) \end_layout \begin_layout Code Proto Recv-Q Send-Q Local Address Foreign Address State \end_layout \begin_layout Code ¬ PID/Program name \end_layout \begin_layout Code tcp 0 0 0.0.0.0:32768 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 1258/rpc.statd \end_layout \begin_layout Code tcp 0 0 0.0.0.0:32769 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 1502/rpc.mountd \end_layout \begin_layout Code tcp 0 0 0.0.0.0:515 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 22433/lpd Waiting \end_layout \begin_layout Code tcp 0 0 1.2.3.1:139 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 1746/smbd \end_layout \begin_layout Code tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 1230/portmap \end_layout \begin_layout Code tcp 0 0 0.0.0.0:6000 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 3551/X \end_layout \begin_layout Code tcp 0 0 1.2.3.1:8081 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 18735/junkbuster \end_layout \begin_layout Code tcp 0 0 1.2.3.1:3128 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 18822/(squid) \end_layout \begin_layout Code tcp 0 0 127.0.0.1:953 0.0.0.0:* LISTEN \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Code tcp 0 0 ::ffff:1.2.3.1:993 :::* LISTEN \end_layout \begin_layout Code ¬ 6742/xinetd-ipv6 \end_layout \begin_layout Code tcp 0 0 :::13 :::* LISTEN \end_layout \begin_layout Code ¬ 6742/xinetd-ipv6 \end_layout \begin_layout Code tcp 0 0 ::ffff:1.2.3.1:143 :::* LISTEN \end_layout \begin_layout Code ¬ 6742/xinetd-ipv6 \end_layout \begin_layout Code tcp 0 0 :::53 :::* LISTEN \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Code tcp 0 0 :::22 :::* LISTEN \end_layout \begin_layout Code ¬ 1410/sshd \end_layout \begin_layout Code tcp 0 0 :::6010 :::* LISTEN \end_layout \begin_layout Code ¬ 13237/sshd \end_layout \begin_layout Code udp 0 0 0.0.0.0:32768 0.0.0.0:* \end_layout \begin_layout Code ¬ 1258/rpc.statd \end_layout \begin_layout Code udp 0 0 0.0.0.0:2049 0.0.0.0:* \end_layout \begin_layout Code ¬ - \end_layout \begin_layout Code udp 0 0 0.0.0.0:32770 0.0.0.0:* \end_layout \begin_layout Code ¬ 1502/rpc.mountd \end_layout \begin_layout Code udp 0 0 0.0.0.0:32771 0.0.0.0:* \end_layout \begin_layout Code ¬ - \end_layout \begin_layout Code udp 0 0 1.2.3.1:137 0.0.0.0:* \end_layout \begin_layout Code ¬ 1751/nmbd \end_layout \begin_layout Code udp 0 0 0.0.0.0:137 0.0.0.0:* \end_layout \begin_layout Code ¬ 1751/nmbd \end_layout \begin_layout Code udp 0 0 1.2.3.1:138 0.0.0.0:* \end_layout \begin_layout Code ¬ 1751/nmbd \end_layout \begin_layout Code udp 0 0 0.0.0.0:138 0.0.0.0:* \end_layout \begin_layout Code ¬ 1751/nmbd \end_layout \begin_layout Code udp 0 0 0.0.0.0:33044 0.0.0.0:* \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Code udp 0 0 1.2.3.1:53 0.0.0.0:* \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Code udp 0 0 127.0.0.1:53 0.0.0.0:* \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Code udp 0 0 0.0.0.0:67 0.0.0.0:* \end_layout \begin_layout Code ¬ 1530/dhcpd \end_layout \begin_layout Code udp 0 0 0.0.0.0:67 0.0.0.0:* \end_layout \begin_layout Code ¬ 1530/dhcpd \end_layout \begin_layout Code udp 0 0 0.0.0.0:32858 0.0.0.0:* \end_layout \begin_layout Code ¬ 18822/(squid) \end_layout \begin_layout Code udp 0 0 0.0.0.0:4827 0.0.0.0:* \end_layout \begin_layout Code ¬ 18822/(squid) \end_layout \begin_layout Code udp 0 0 0.0.0.0:111 0.0.0.0:* \end_layout \begin_layout Code ¬ 1230/portmap \end_layout \begin_layout Code udp 0 0 :::53 :::* \end_layout \begin_layout Code ¬ 30734/named \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "examples-tcpdump" \end_inset Examples for tcpdump packet dumps \end_layout \begin_layout Standard Here some examples of captured packets are shown, perhaps useful for your own debugging... \end_layout \begin_layout Standard ...more coming next... \end_layout \begin_layout Subsection Router discovery \end_layout \begin_layout Subsubsection Router advertisement \end_layout \begin_layout Code 15:43:49.484751 fe80::212:34ff:fe12:3450 > ff02::1: icmp6: router \end_layout \begin_layout Code ¬ advertisement(chlim=64, router_ltime=30, reachable_time=0, \end_layout \begin_layout Code ¬ retrans_time=0)(prefix info: AR valid_ltime=30, preffered_ltime=20, \end_layout \begin_layout Code ¬ prefix=2002:0102:0304:1::/64)(prefix info: LAR valid_ltime=2592000, \end_layout \begin_layout Code ¬ preffered_ltime=604800, prefix=2001:0db8:0:1::/64)(src lladdr: \end_layout \begin_layout Code ¬ 0:12:34:12:34:50) (len 88, hlim 255) \end_layout \begin_layout Standard Router with link-local address \begin_inset Quotes sld \end_inset fe80::212:34ff:fe12:3450 \begin_inset Quotes srd \end_inset send an advertisement to the all-node-on-link multicast address \begin_inset Quotes sld \end_inset ff02::1 \begin_inset Quotes srd \end_inset containing two prefixes \begin_inset Quotes sld \end_inset 2002:0102:0304:1::/64 \begin_inset Quotes srd \end_inset (lifetime 30 s) and \begin_inset Quotes sld \end_inset 2001:0db8:0:1::/64 \begin_inset Quotes srd \end_inset (lifetime 2592000 s) including its own layer 2 MAC address \begin_inset Quotes sld \end_inset 0:12:34:12:34:50 \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsubsection Router solicitation \end_layout \begin_layout Code 15:44:21.152646 fe80::212:34ff:fe12:3456 > ff02::2: icmp6: router solicitation \end_layout \begin_layout Code ¬ (src lladdr: 0:12:34:12:34:56) (len 16, hlim 255) \end_layout \begin_layout Standard Node with link-local address \begin_inset Quotes sld \end_inset fe80::212:34ff:fe12:3456 \begin_inset Quotes srd \end_inset and layer 2 MAC address \begin_inset Quotes sld \end_inset 0:12:34:12:34:56 \begin_inset Quotes srd \end_inset is looking for a router on-link, therefore sending this solicitation to the all-router-on-link multicast address \begin_inset Quotes sld \end_inset ff02::2 \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsection Neighbor discovery \end_layout \begin_layout Subsubsection Neighbor discovery solicitation for duplicate address detection \end_layout \begin_layout Standard Following packets are sent by a node with layer 2 MAC address \begin_inset Quotes sld \end_inset 0:12:34:12:34:56 \begin_inset Quotes srd \end_inset during autoconfiguration to check whether a potential address is already used by another node on the link sending this to the solicited-node link-local multicast address. \end_layout \begin_layout Itemize Node wants to configure its link-local address \begin_inset Quotes sld \end_inset fe80::212:34ff:fe12:3456 \begin_inset Quotes srd \end_inset , checks for duplicate now \end_layout \begin_layout Code 15:44:17.712338 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has \end_layout \begin_layout Code ¬ fe80::212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim 255) \end_layout \begin_layout Itemize Node wants to configure its global address \begin_inset Quotes sld \end_inset 2002:0102:0304:1:212:34ff:fe12:3456 \begin_inset Quotes srd \end_inset (after receiving advertisement shown above), checks for duplicate now \end_layout \begin_layout Code 15:44:21.905596 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has \end_layout \begin_layout Code ¬ 2002:0102:0304:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, \end_layout \begin_layout Code ¬ hlim 255) \end_layout \begin_layout Itemize Node wants to configure its global address \begin_inset Quotes sld \end_inset 2001:0db8:0:1:212:34ff:fe12:3456 \begin_inset Quotes srd \end_inset (after receiving advertisement shown above), checks for duplicate now \end_layout \begin_layout Code 15:44:22.304028 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has \end_layout \begin_layout Code ¬ 2001:0db8:0:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim \end_layout \begin_layout Code ¬ 255) \end_layout \begin_layout Subsubsection Neighbor discovery solicitation for looking for host or gateway \end_layout \begin_layout Itemize Node wants to send packages to \begin_inset Quotes sld \end_inset 2001:0db8:0:1::10 \begin_inset Quotes srd \end_inset but has no layer 2 MAC address to send packet, so send solicitation now \end_layout \begin_layout Code 13:07:47.664538 2002:0102:0304:1:2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6: \end_layout \begin_layout Code ¬ neighbor sol: who has 2001:0db8:0:1::10(src lladdr: 0:e0:18:90:92:5) (len 32, \end_layout \begin_layout Code ¬ hlim 255) \end_layout \begin_layout Itemize Node looks for \begin_inset Quotes sld \end_inset fe80::10 \begin_inset Quotes srd \end_inset now \end_layout \begin_layout Code 13:11:20.870070 fe80::2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6: neighbor \end_layout \begin_layout Code ¬ sol: who has fe80::10(src lladdr: 0:e0:18:90:92:5) (len 32, hlim 255) \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-support-persistent-configuration" \end_inset Support for persistent IPv6 configuration in Linux distributions \end_layout \begin_layout Standard Some Linux distribution contain already support of a persistent IPv6 configurati on using existing or new configuration and script files and some hook in the IPv4 script files. \end_layout \begin_layout Section Red Hat Linux and \begin_inset Quotes sld \end_inset clones \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard Since starting writing the \begin_inset CommandInset href LatexCommand href name "IPv6 & Linux - HowTo" target "http://www.bieringer.de/linux/IPv6/" \end_inset it was my intention to enable a persistent IPv6 configuration which catch most of the wished cases like host-only, router-only, dual-homed-host, router with second stub network, normal tunnels, 6to4 tunnels, and so on. Nowadays there exists a set of configuration and script files which do the job very well (never heard about real problems, but I don't know how many use the set). Because this configuration and script files are extended from time to time, they got their own homepage: \begin_inset CommandInset href LatexCommand href name "initscripts-ipv6 homepage" target "http://www.deepspace6.net/projects/initscripts-ipv6.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/projects/initscripts-ipv6.html" \end_inset ). Because I began my IPv6 experience using a Red Hat Linux 5.0 clone, my IPv6 development systems are mostly Red Hat Linux based now, it's kind a logic that the scripts are developed for this kind of distribution (so called \emph on historic issue \emph default ). Also it was very easy to extend some configuration files, create new ones and create some simple hook for calling IPv6 setup during IPv4 setup. \end_layout \begin_layout Standard Fortunately, in Red Hat Linux since 7.1 a snapshot of my IPv6 scripts is included, this was and is still further on assisted by Pekka Savola. \end_layout \begin_layout Standard Mandrake since version 8.0 also includes an IPv6-enabled initscript package, but a minor bug still prevents usage ( \begin_inset Quotes sld \end_inset ifconfig \begin_inset Quotes srd \end_inset misses \begin_inset Quotes sld \end_inset inet6 \begin_inset Quotes srd \end_inset before \begin_inset Quotes sld \end_inset add \begin_inset Quotes srd \end_inset ). \end_layout \begin_layout Subsection Test for IPv6 support of network configuration scripts \end_layout \begin_layout Standard You can test, whether your Linux distribution contain support for persistent IPv6 configuration using my set. Following script library should exist: \end_layout \begin_layout Code /etc/sysconfig/network-scripts/network-functions-ipv6 \end_layout \begin_layout Standard Auto-magically test: \end_layout \begin_layout Code # test -f /etc/sysconfig/network-scripts/network-functions-ipv6 && echo "Main \end_layout \begin_layout Code ¬ IPv6 script library exists" \end_layout \begin_layout Standard The version of the library is important if you miss some features. You can get it executing following (or easier look at the top of the file): \end_layout \begin_layout Code # source /etc/sysconfig/network-scripts/network-functions-ipv6 && \end_layout \begin_layout Code ¬ getversion_ipv6_functions \end_layout \begin_layout Code 20011124 \end_layout \begin_layout Standard In shown example, the used version is \series bold 20011124 \series default . Check this against latest information on \begin_inset CommandInset href LatexCommand href name "initscripts-ipv6 homepage" target "http://www.deepspace6.net/projects/initscripts-ipv6.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/projects/initscripts-ipv6.html" \end_inset ) to see what has been changed. You will find there also a change-log. \end_layout \begin_layout Subsection Short hint for enabling IPv6 on current RHL 7.1, 7.2, 7.3, ... \end_layout \begin_layout Itemize Check whether running system has already IPv6 module loaded \end_layout \begin_layout Code # modprobe -c | grep net-pf-10 \end_layout \begin_layout Code alias net-pf-10 off \end_layout \begin_layout Itemize If result is \begin_inset Quotes sld \end_inset off \begin_inset Quotes srd \end_inset , then enable IPv6 networking by editing /etc/sysconfig/network, add following new line \end_layout \begin_layout Code NETWORKING_IPV6=yes \end_layout \begin_layout Itemize Reboot or restart networking using \end_layout \begin_layout Code # service network restart \end_layout \begin_layout Itemize Now IPv6 module should be loaded \end_layout \begin_layout Code # modprobe -c | grep ipv6 \end_layout \begin_layout Code alias net-pf-10 ipv6 \end_layout \begin_layout Standard If your system is on a link which provides router advertisement, autoconfigurati on will be done automatically. For more information which settings are supported see /usr/share/doc/initscript s-$version/sysconfig.txt. \end_layout \begin_layout Section SuSE Linux \end_layout \begin_layout Standard In newer 7.x versions there is a really rudimentary support available, see /etc/rc.config for details. \end_layout \begin_layout Standard Because of the really different configuration and script file structure it is hard (or impossible) to use the set for Red Hat Linux and clones with this distribution. \begin_inset Newline newline \end_inset In versions 8.x they completly change their configuration setup. \end_layout \begin_layout Subsection SuSE Linux 7.3 \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "How to setup 6to4 IPv6 with SuSE 7.3" target "http://www.feyrer.de/IPv6/SuSE73-IPv6+6to4-setup.html" \end_inset \end_layout \begin_layout Subsection SuSE Linux 8.0 \end_layout \begin_layout Subsubsection IPv6 address configuration \end_layout \begin_layout Standard Edit file /etc/sysconfig/network/ifcfg- and setup following value \end_layout \begin_layout Code IP6ADDR="/" \end_layout \begin_layout Subsubsection Additional information \end_layout \begin_layout Standard See file /usr/share/doc/packages/sysconfig/README \end_layout \begin_layout Subsection SuSE Linux 8.1 \end_layout \begin_layout Subsubsection IPv6 address configuration \end_layout \begin_layout Standard Edit file /etc/sysconfig/network/ifcfg- and setup following value \end_layout \begin_layout Code IPADDR="/" \end_layout \begin_layout Subsubsection Additional information \end_layout \begin_layout Standard See file /usr/share/doc/packages/sysconfig/Network \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "Configuration-Debian-Linux" \end_inset Debian Linux \end_layout \begin_layout Standard Following information was contributed by Stephane Bortzmeyer \end_layout \begin_layout Enumerate Be sure that IPv6 is loaded, either because it is compiled into the kernel or because the module is loaded. For the latest, three solutions, adding it to /etc/modules, using the pre-up trick shown later or using kmod (not detailed here). \end_layout \begin_layout Enumerate Configure your interface. Here we assume eth0 and address (2001:0db8:1234:5::1:1). Edit /etc/network/interfaces: \end_layout \begin_layout Code iface eth0 inet6 static \end_layout \begin_layout Code pre-up modprobe ipv6 \end_layout \begin_layout Code address 2001:0db8:1234:5::1:1 \end_layout \begin_layout Code # To suppress completely autoconfiguration: \end_layout \begin_layout Code # up echo 0 > /proc/sys/net/ipv6/conf/all/autoconf \end_layout \begin_layout Code netmask 64 \end_layout \begin_layout Code # The router is autoconfigured and has no fixed address. \end_layout \begin_layout Code # It is magically \end_layout \begin_layout Code # found. (/proc/sys/net/ipv6/conf/all/accept_ra). Otherwise: \end_layout \begin_layout Code #gateway 2001:0db8:1234:5::1 \end_layout \begin_layout Standard And you reboot or you just \end_layout \begin_layout Code # ifup --force eth0 \end_layout \begin_layout Standard and you have your static address. \end_layout \begin_layout Subsection Further information \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "IPv6 with Debian Linux" target "http://ipv6.debian.net/" \end_inset \end_layout \begin_layout Itemize Jean-Marc V. Liotier's \begin_inset CommandInset href LatexCommand href name "HOWTO for Freenet6 & Debian Users" target "http://www.ruwenzori.net/ipv6/Jims_LAN_IPv6_global_connectivity_howto.html" \end_inset (announced 24.12.2002 on \begin_inset CommandInset ref LatexCommand ref name "mailinglist" reference "information-maillists" \end_inset users@ipv6.org ) \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-autoconfiguration" \end_inset Auto-configuration \end_layout \begin_layout Section Stateless auto-configuration out-of-the-box \end_layout \begin_layout Standard Is supported and seen on the assigned link-local address after an IPv6-enabled interface is up. \end_layout \begin_layout Standard Example: \end_layout \begin_layout Code # ip -6 addr show dev eth0 scope link \end_layout \begin_layout Code 2: eth0: mtu 1500 qlen1000 \end_layout \begin_layout Code inet6 fe80::211:d8ff:fe6b:f0f5/64 scope link \end_layout \begin_layout Code valid_lft forever preferred_lft forever \end_layout \begin_layout Section Stateless auto-configuration using Router Advertisement Daemon (radvd) \end_layout \begin_layout Standard to be filled. See \begin_inset CommandInset ref LatexCommand ref name "radvd daemon autoconfiguration" reference "hints-daemons-radvd" \end_inset below. \end_layout \begin_layout Section Dynamic Host Configuration Protocol v6 (DHCPv6) \end_layout \begin_layout Standard After a long time discussing issues, finally \begin_inset CommandInset href LatexCommand href name "RFC 3315 / Dynamic Host Configuration Protocol for IPv6 (DHCPv6)" target "http://www.faqs.org/rfcs/rfc3315.html" \end_inset was finished. At time updating this part (10/2005) currently two implementations are available: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Dibbler" target "http://klub.com.pl/dhcpv6/" \end_inset by Tomasz Mrugalski ( \begin_inset CommandInset ref LatexCommand ref name "Hints for configuration" reference "hints-daemons-dibbler" \end_inset ) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "dhcpv6" target "https://fedorahosted.org/dhcpv6/" \end_inset ( \begin_inset CommandInset ref LatexCommand ref name "Hints for configuration" reference "hints-daemons-dhcpv6" \end_inset ) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ISC DHCP" target "http://www.isc.org/software/dhcp" \end_inset ( \begin_inset CommandInset ref LatexCommand ref name "Hints for configuration" reference "hints-daemons-isc-dhcp" \end_inset ) \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-mobility" \end_inset Mobility \end_layout \begin_layout Section Common information \end_layout \begin_layout Subsection Node Mobility \end_layout \begin_layout Standard Support for IPv6 mobility can be enabled in Linux by installing the MIPL2 implementation found at: \begin_inset CommandInset href LatexCommand href name "http://www.mobile-ipv6.org/" target "http://www.mobile-ipv6.org/" \end_inset \end_layout \begin_layout Standard This implementation is compliant with RFC 3775. It is composed of a kernel patch and a mobility daemon called mip6d. Version 2.0.1 applies on Linux kernel 2.6.15. \end_layout \begin_layout Standard Installation and setup are described in the \begin_inset CommandInset href LatexCommand href name "Linux Mobile IPv6 HOWTO" target "http://tldp.org/HOWTO/Mobile-IPv6-HOWTO/" \end_inset . \end_layout \begin_layout Subsection Network Mobility \end_layout \begin_layout Standard There also exists an implementation of network mobility for Linux, it is called NEPL and is based on MIPL. It can also be downloaded from: \begin_inset CommandInset href LatexCommand href name "http://www.mobile-ipv6.org/" target "http://www.mobile-ipv6.org/" \end_inset . \end_layout \begin_layout Standard The HOWTO document describing setup and configuration is available at: \begin_inset CommandInset href LatexCommand href name "http://www.nautilus6.org/doc/nepl-howto/" target "http://www.nautilus6.org/doc/nepl-howto/" \end_inset . \end_layout \begin_layout Subsection Links \end_layout \begin_layout Itemize Mobile IPv6 for Linux (MIPL) project: \begin_inset CommandInset href LatexCommand href name "http://www.mobile-ipv6.org/" target "http://www.mobile-ipv6.org/" \end_inset \end_layout \begin_layout Itemize Nautilus6 working group: \begin_inset CommandInset href LatexCommand href name "http://nautilus6.org/" target "http://nautilus6.org/" \end_inset \end_layout \begin_layout Itemize Fast Handovers for Mobile IPv6 for Linux project: \begin_inset CommandInset href LatexCommand href name "http://www.fmipv6.org/" target "http://www.fmipv6.org/" \end_inset \end_layout \begin_layout Itemize USAGI-patched Mobile IPv6 for Linux (UMIP): \begin_inset CommandInset href LatexCommand href name "http://umip.linux-ipv6.org/" target "http://umip.linux-ipv6.org/" \end_inset \end_layout \begin_layout Itemize Deploying IPsec/IKE-protected MIPv6 under Linux: \begin_inset CommandInset href LatexCommand href name "http://natisbad.org/MIPv6/" target "http://natisbad.org/MIPv6/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3775 / Mobility Support in IPv6" target "http://www.faqs.org/rfcs/rfc3775.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3776 / Using IPsec to Protect Mobile IPv6 Signaling Between Mobile Nodes and Home Agents" target "http://www.faqs.org/rfcs/rfc3776.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3963 / Network Mobility (NEMO)" target "http://www.faqs.org/rfcs/rfc3963.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 4068 / Fast Handovers for Mobile IPv6" target "http://www.faqs.org/rfcs/rfc4068.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 4423 / Host Identity Protocol (HIP) Architecture" target "http://www.faqs.org/rfcs/rfc4423.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 5201 / Host Identity Protocol" target "http://www.faqs.org/rfcs/rfc5201.html" \end_inset \end_layout \begin_layout Itemize HIP implementations: \begin_inset CommandInset href LatexCommand href name "http://infrahip.hiit.fi/" target "http://infrahip.hiit.fi/" \end_inset , \begin_inset CommandInset href LatexCommand href name "http://hip4inter.net/" target "http://hip4inter.net/" \end_inset , \begin_inset CommandInset href LatexCommand href name "http://www.openhip.org/" target "http://www.openhip.org/" \end_inset \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-firewalling-security" \end_inset Firewalling \end_layout \begin_layout Standard IPv6 firewalling is important, especially if using IPv6 on internal networks with global IPv6 addresses. Because unlike at IPv4 networks where in common internal hosts are protected automatically using private IPv4 addresses like \begin_inset CommandInset href LatexCommand href name "RFC 1918 / Address Allocation for Private Internets" target "http://www.faqs.org/rfcs/rfc1918.html" \end_inset or Automatic Private IP Addressing (APIPA) \begin_inset CommandInset href LatexCommand href name "Google search for Microsoft + APIPA" target "http://www.google.com/search?q=apipa+microsoft" \end_inset , in IPv6 normally global addresses are used and someone with IPv6 connectivity can reach all internal IPv6 enabled nodes. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "firewalling-netfilter6" \end_inset Firewalling using netfilter6 \end_layout \begin_layout Standard Native IPv6 firewalling is only supported in kernel versions 2.4+. In older 2.2- you can only filter IPv6-in-IPv4 by protocol 41. \end_layout \begin_layout Standard Attention: no warranty that described rules or examples can really protect your system! \end_layout \begin_layout Standard Audit your ruleset after installation, see \begin_inset CommandInset ref LatexCommand ref reference "IPv6-security-auditing" \end_inset for more. \end_layout \begin_layout Standard Since kernel version 2.6.20 (February 2007) IPv6 connection tracking is fully working (and does not break IPv4 NAT anymore like versions before) \end_layout \begin_layout Standard Since kernel version 3.9.0 (April 2013) NAT for IPv6 is supported with ip6tables >= 1.4.18 \end_layout \begin_layout Standard Since kernel version 3.13 (April 2014) new framework introduced named: nftables \end_layout \begin_layout Subsection More information \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Netfilter project" target "http://www.netfilter.org/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "maillist archive of netfilter users" target "https://lists.netfilter.org/mailman/listinfo/netfilter" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "maillist archive of netfilter developers" target "https://lists.netfilter.org/mailman/listinfo/netfilter-devel" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Unofficial status informations" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-kernel.html#netfilter6 " \end_inset \end_layout \begin_layout Section Preparation \end_layout \begin_layout Standard This step is only needed if distributed kernel and netfilter doesn't fit your requirements and new features are available but still not built-in. \end_layout \begin_layout Subsection Get sources \end_layout \begin_layout Standard Get the latest kernel source: \begin_inset CommandInset href LatexCommand href name "http://www.kernel.org/" target "http://www.kernel.org/" \end_inset \end_layout \begin_layout Standard Get the latest iptables package: \end_layout \begin_layout Itemize Source tarball (for kernel patches): \begin_inset CommandInset href LatexCommand href name "http://www.netfilter.org/" target "http://www.netfilter.org/" \end_inset \end_layout \begin_layout Subsection Extract sources \end_layout \begin_layout Standard Change to source directory: \end_layout \begin_layout Code # cd /path/to/src \end_layout \begin_layout Standard Unpack and rename kernel sources \end_layout \begin_layout Code # tar z|jxf kernel-version.tar.gz|bz2 \end_layout \begin_layout Code # mv linux linux-version-iptables-version+IPv6 \end_layout \begin_layout Standard Unpack iptables sources \end_layout \begin_layout Code # tar z|jxf iptables-version.tar.gz|bz2 \end_layout \begin_layout Subsection Apply latest iptables/IPv6-related patches to kernel source \end_layout \begin_layout Standard Change to iptables directory \end_layout \begin_layout Code # cd iptables-version \end_layout \begin_layout Standard Apply pending patches \end_layout \begin_layout Code # make pending-patches KERNEL_DIR=/path/to/src/linux-version-iptables-version/ \end_layout \begin_layout Standard Apply additional IPv6 related patches (still not in the vanilla kernel included) \end_layout \begin_layout Code # make patch-o-matic KERNEL_DIR=/path/to/src/linux-version-iptables-version/ \end_layout \begin_layout Standard Say yes at following options (iptables-1.2.2) \end_layout \begin_layout Itemize ah-esp.patch \end_layout \begin_layout Itemize masq-dynaddr.patch (only needed for systems with dynamic IP assigned WAN connections like PPP or PPPoE) \end_layout \begin_layout Itemize ipv6-agr.patch.ipv6 \end_layout \begin_layout Itemize ipv6-ports.patch.ipv6 \end_layout \begin_layout Itemize LOG.patch.ipv6 \end_layout \begin_layout Itemize REJECT.patch.ipv6 \end_layout \begin_layout Standard Check IPv6 extensions \end_layout \begin_layout Code # make print-extensions \end_layout \begin_layout Code Extensions found: IPv6:owner IPv6:limit IPv6:mac IPv6:multiport \end_layout \begin_layout Subsection Configure, build and install new kernel \end_layout \begin_layout Standard Change to kernel sources \end_layout \begin_layout Code # cd /path/to/src/linux-version-iptables-version/ \end_layout \begin_layout Standard Edit Makefile \end_layout \begin_layout Code - EXTRAVERSION = \end_layout \begin_layout Code + EXTRAVERSION = -iptables-version+IPv6-try \end_layout \begin_layout Standard Run configure, enable IPv6 related \end_layout \begin_layout Code Code maturity level options \end_layout \begin_layout Code Prompt for development and/or incomplete code/drivers : yes \end_layout \begin_layout Code Networking options \end_layout \begin_layout Code Network packet filtering: yes \end_layout \begin_layout Code The IPv6 protocol: module \end_layout \begin_layout Code IPv6: Netfilter Configuration \end_layout \begin_layout Code IP6 tables support: module \end_layout \begin_layout Code All new options like following: \end_layout \begin_layout Code limit match support: module \end_layout \begin_layout Code MAC address match support: module \end_layout \begin_layout Code Multiple port match support: module \end_layout \begin_layout Code Owner match support: module \end_layout \begin_layout Code netfilter MARK match support: module \end_layout \begin_layout Code Aggregated address check: module \end_layout \begin_layout Code Packet filtering: module \end_layout \begin_layout Code REJECT target support: module \end_layout \begin_layout Code LOG target support: module \end_layout \begin_layout Code Packet mangling: module \end_layout \begin_layout Code MARK target support: module \end_layout \begin_layout Standard Configure other related to your system, too \end_layout \begin_layout Standard Compilation and installing: see the kernel section here and other HOWTOs \end_layout \begin_layout Subsection Rebuild and install binaries of iptables \end_layout \begin_layout Standard Make sure, that upper kernel source tree is also available at /usr/src/linux/ \end_layout \begin_layout Standard Rename older directory \end_layout \begin_layout Code # mv /usr/src/linux /usr/src/linux.old \end_layout \begin_layout Standard Create a new softlink \end_layout \begin_layout Code # ln -s /path/to/src/linux-version-iptables-version /usr/src/linux \end_layout \begin_layout Standard Rebuild SRPMS \end_layout \begin_layout Code # rpm --rebuild /path/to/SRPMS/iptables-version-release.src.rpm \end_layout \begin_layout Standard Install new iptables packages (iptables + iptables-ipv6) \end_layout \begin_layout Itemize On RH 7.1 systems, normally, already an older version is installed, therefore use "freshen" \end_layout \begin_layout Code # rpm -Fhv /path/to/RPMS/cpu/iptables*-version-release.cpu.rpm \end_layout \begin_layout Itemize If not already installed, use "install" \end_layout \begin_layout Code # rpm -ihv /path/to/RPMS/cpu/iptables*-version-release.cpu.rpm \end_layout \begin_layout Itemize On RH 6.2 systems, normally, no kernel 2.4.x is installed, therefore the requiremen ts don't fit. Use "--nodeps" to install it \end_layout \begin_layout Code # rpm -ihv --nodeps /path/to/RPMS/cpu/iptables*-version-release.cpu.rpm \end_layout \begin_layout Standard Perhaps it's necessary to create a softlink for iptables libraries where iptables looks for them \end_layout \begin_layout Code # ln -s /lib/iptables/ /usr/lib/iptables \end_layout \begin_layout Section Usage of ip6tables \end_layout \begin_layout Subsection Check for support \end_layout \begin_layout Standard Load module, if so compiled \end_layout \begin_layout Code # modprobe ip6_tables \end_layout \begin_layout Standard Check for capability \end_layout \begin_layout Code # [ ! -f /proc/net/ip6_tables_names ] && echo "Current kernel doesn't support \end_layout \begin_layout Code ¬ 'ip6tables' firewalling (IPv6)!" \end_layout \begin_layout Subsection Learn how to use ip6tables \end_layout \begin_layout Subsubsection List all IPv6 netfilter entries \end_layout \begin_layout Itemize Short \end_layout \begin_layout Code # ip6tables -L \end_layout \begin_layout Itemize Extended \end_layout \begin_layout Code # ip6tables -n -v --line-numbers -L \end_layout \begin_layout Subsubsection List specified filter \end_layout \begin_layout Code # ip6tables -n -v --line-numbers -L INPUT \end_layout \begin_layout Subsubsection Insert a log rule at the input filter with options \end_layout \begin_layout Code # ip6tables --table filter --append INPUT -j LOG --log-prefix "INPUT:" \end_layout \begin_layout Code ¬ --log-level 7 \end_layout \begin_layout Subsubsection Insert a drop rule at the input filter \end_layout \begin_layout Code # ip6tables --table filter --append INPUT -j DROP \end_layout \begin_layout Subsubsection Delete a rule by number \end_layout \begin_layout Code # ip6tables --table filter --delete INPUT 1 \end_layout \begin_layout Subsubsection Enable connection tracking \end_layout \begin_layout Standard Since kernel version 2.6.20 IPv6 connection tracking is well supported and should be used instead of using stateless filter rules. \end_layout \begin_layout Code # ip6tables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT \end_layout \begin_layout Subsubsection Allow ICMPv6 \end_layout \begin_layout Standard Using older kernels (unpatched kernel 2.4.5 and iptables-1.2.2) no type can be specified \end_layout \begin_layout Itemize Accept incoming ICMPv6 through tunnels \end_layout \begin_layout Code # ip6tables -A INPUT -i sit+ -p icmpv6 -j ACCEPT \end_layout \begin_layout Itemize Allow outgoing ICMPv6 through tunnels \end_layout \begin_layout Code # ip6tables -A OUTPUT -o sit+ -p icmpv6 -j ACCEPT \end_layout \begin_layout Standard Newer kernels allow specifying of ICMPv6 types: \end_layout \begin_layout Code # ip6tables -A INPUT -p icmpv6 --icmpv6-type echo-request -j ACCEPT \end_layout \begin_layout Subsubsection Rate-limiting \end_layout \begin_layout Standard Because it can happen (author already saw it to times) that an ICMPv6 storm will raise up, you should use available rate limiting for at least ICMPv6 ruleset. In addition logging rules should also get rate limiting to prevent DoS attacks against syslog and storage of log file partition. An example for a rate limited ICMPv6 looks like: \end_layout \begin_layout Code # ip6tables -A INPUT --protocol icmpv6 --icmpv6-type echo-request \end_layout \begin_layout Code ¬ -j ACCEPT --match limit --limit 30/minute \end_layout \begin_layout Subsubsection Allow incoming SSH \end_layout \begin_layout Standard Here an example is shown for a ruleset which allows incoming SSH connection from a specified IPv6 address \end_layout \begin_layout Itemize Allow incoming SSH from 2001:0db8:100::1/128 \end_layout \begin_layout Code # ip6tables -A INPUT -i sit+ -p tcp -s 2001:0db8:100::1/128 --sport 512:65535 \end_layout \begin_layout Code ¬ --dport 22 -j ACCEPT \end_layout \begin_layout Itemize Allow response packets ( \series bold no longer needed if connection tracking is used! \series default ) \end_layout \begin_layout Code # ip6tables -A OUTPUT -o sit+ -p tcp -d 2001:0db8:100::1/128 --dport 512:65535 \end_layout \begin_layout Code ¬ --sport 22 ! --syn -j ACCEPT \end_layout \begin_layout Subsubsection Enable tunneled IPv6-in-IPv4 \end_layout \begin_layout Standard To accept tunneled IPv6-in-IPv4 packets, you have to insert rules in your \series bold IPv4 firewall setup \series default relating to such packets, for example \end_layout \begin_layout Itemize Accept incoming IPv6-in-IPv4 on interface ppp0 \end_layout \begin_layout Code # iptables -A INPUT -i ppp0 -p ipv6 -j ACCEPT \end_layout \begin_layout Itemize Allow outgoing IPv6-in-IPv4 to interface ppp0 \end_layout \begin_layout Code # iptables -A OUTPUT -o ppp0 -p ipv6 -j ACCEPT \end_layout \begin_layout Standard If you have only a static tunnel, you can specify the IPv4 addresses, too, like \end_layout \begin_layout Itemize Accept incoming IPv6-in-IPv4 on interface ppp0 from tunnel endpoint 192.0.2.2 \end_layout \begin_layout Code # iptables -A INPUT -i ppp0 -p ipv6 -s 192.0.2.2 -j ACCEPT \end_layout \begin_layout Itemize Allow outgoing IPv6-in-IPv4 to interface ppp0 to tunnel endpoint 192.0.2.2 \end_layout \begin_layout Code # iptables -A OUTPUT -o ppp0 -p ipv6 -d 192.0.2.2 -j ACCEPT \end_layout \begin_layout Subsubsection Protection against incoming TCP connection requests \end_layout \begin_layout Standard \series bold VERY RECOMMENDED! \series default For security issues you should really insert a rule which blocks incoming TCP connection requests. Adapt "-i" option, if other interface names are in use! \end_layout \begin_layout Itemize Block incoming TCP connection requests to this host \end_layout \begin_layout Code # ip6tables -I INPUT -i sit+ -p tcp --syn -j DROP \end_layout \begin_layout Itemize Block incoming TCP connection requests to hosts behind this router \end_layout \begin_layout Code # ip6tables -I FORWARD -i sit+ -p tcp --syn -j DROP \end_layout \begin_layout Standard Perhaps the rules have to be placed below others, but that is work you have to think about it. Best way is to create a script and execute rules in a specified way. \end_layout \begin_layout Subsubsection Protection against incoming UDP connection requests \end_layout \begin_layout Standard \series bold ALSO RECOMMENDED! \series default Like mentioned on my firewall information it's possible to control the ports on outgoing UDP/TCP sessions. So if all of your local IPv6 systems are using local ports e.g. from 32768 to 60999 you are able to filter UDP connections also (until connection tracking works) like: \end_layout \begin_layout Itemize Block incoming UDP packets which cannot be responses of outgoing requests of this host \end_layout \begin_layout Code # ip6tables -I INPUT -i sit+ -p udp ! --dport 32768:60999 -j DROP \end_layout \begin_layout Itemize Block incoming UDP packets which cannot be responses of forwarded requests of hosts behind this router \end_layout \begin_layout Code # ip6tables -I FORWARD -i sit+ -p udp ! --dport 32768:60999 -j DROP \end_layout \begin_layout Subsection Examples \end_layout \begin_layout Subsubsection Simple example for Fedora \end_layout \begin_layout Standard Following lines show a simple firewall configuration for Fedora 6 (since kernel version 2.6.20). It was modfied from the default one (generated by \shape italic system-config-firewall \shape default ) for supporting connection \series bold tracking \series default and return the proper ICMPv6 code for rejects. Incoming SSH (port 22) connections are allowed. \end_layout \begin_layout Code File: /etc/sysconfig/ip6tables \end_layout \begin_layout Code \end_layout \begin_layout Code *filter :INPUT ACCEPT [0:0] \end_layout \begin_layout Code :FORWARD ACCEPT [0:0] \end_layout \begin_layout Code :OUTPUT ACCEPT [0:0] \end_layout \begin_layout Code :RH-Firewall-1-INPUT - [0:0] \end_layout \begin_layout Code -A INPUT -j RH-Firewall-1-INPUT \end_layout \begin_layout Code -A FORWARD -j RH-Firewall-1-INPUT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -i lo -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p icmpv6 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p 50 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p 51 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p udp --dport 5353 -d ff02::fb -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -m state --state NEW -p tcp --dport 22 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp6-adm-prohibited \end_layout \begin_layout Code COMMIT \end_layout \begin_layout Standard For completeness also the IPv4 configuration is shown here: \end_layout \begin_layout Code File: /etc/sysconfig/iptables \end_layout \begin_layout Code \end_layout \begin_layout Code *filter :INPUT ACCEPT [0:0] \end_layout \begin_layout Code :FORWARD ACCEPT [0:0] \end_layout \begin_layout Code :OUTPUT ACCEPT [0:0] \end_layout \begin_layout Code :RH-Firewall-1-INPUT - [0:0] \end_layout \begin_layout Code -A INPUT -j RH-Firewall-1-INPUT \end_layout \begin_layout Code -A FORWARD -j RH-Firewall-1-INPUT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -i lo -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p 50 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p 51 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT \end_layout \begin_layout Code -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited \end_layout \begin_layout Code COMMIT \end_layout \begin_layout Standard Usage: \end_layout \begin_layout Itemize Create/modify the configuration files \end_layout \begin_layout Itemize Activate IPv4 & IPv6 firewalling \end_layout \begin_layout Code # service iptables start \end_layout \begin_layout Code # service ip6tables start \end_layout \begin_layout Itemize Enable automatic start after reboot \end_layout \begin_layout Code # chkconfig iptables on \end_layout \begin_layout Code # chkconfig ip6tables on \end_layout \begin_layout Subsubsection Sophisticated example \end_layout \begin_layout Standard Following lines show a more sophisticated \series bold but still stateless filter \series default setup as an example. Happy netfilter6 ruleset creation.... \end_layout \begin_layout Code # ip6tables -n -v -L \end_layout \begin_layout Code Chain INPUT (policy DROP 0 packets, 0 bytes) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code 0 0 extIN all sit+ * ::/0 ::/0 \end_layout \begin_layout Code 4 384 intIN all eth0 * ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT all * * ::1/128 ::1/128 \end_layout \begin_layout Code 0 0 ACCEPT all lo * ::/0 ::/0 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `INPUT-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain FORWARD (policy DROP 0 packets, 0 bytes) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 int2ext all eth0 sit+ ::/0 ::/0 \end_layout \begin_layout Code 0 0 ext2int all sit+ eth0 ::/0 ::/0 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `FORWARD-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain OUTPUT (policy DROP 0 packets, 0 bytes) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 extOUT all * sit+ ::/0 ::/0 \end_layout \begin_layout Code 4 384 intOUT all * eth0 ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT all * * ::1/128 ::1/128 \end_layout \begin_layout Code 0 0 ACCEPT all * lo ::/0 ::/0 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `OUTPUT-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain ext2int (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT icmpv6 * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ tcp spts:1:65535 dpts:1024:65535 flags:!0x16/0x02 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `ext2int-default:' \end_layout \begin_layout Code 0 0 DROP tcp * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 DROP udp * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain extIN (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT tcp * * 3ffe:400:100::1/128 ::/0 \end_layout \begin_layout Code ¬ tcp spts:512:65535 dpt:22 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * 3ffe:400:100::2/128 ::/0 \end_layout \begin_layout Code ¬ tcp spts:512:65535 dpt:22 \end_layout \begin_layout Code 0 0 ACCEPT icmpv6 * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ tcp spts:1:65535 dpts:1024:65535 flags:!0x16/0x02 \end_layout \begin_layout Code 0 0 ACCEPT udp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ udp spts:1:65535 dpts:1024:65535 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ limit: avg 5/min burst 5 LOG flags 0 level 7 prefix `extIN-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain extOUT (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 \end_layout \begin_layout Code ¬ 2001:0db8:100::1/128tcp spt:22 dpts:512:65535 flags:!0x16/0x02 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 \end_layout \begin_layout Code ¬ 2001:0db8:100::2/128tcp spt:22 dpts:512:65535 flags:!0x16/0x02 \end_layout \begin_layout Code 0 0 ACCEPT icmpv6 * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ tcp spts:1024:65535 dpts:1:65535 \end_layout \begin_layout Code 0 0 ACCEPT udp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ udp spts:1024:65535 dpts:1:65535 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `extOUT-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain int2ext (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT icmpv6 * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 ACCEPT tcp * * ::/0 ::/0 \end_layout \begin_layout Code ¬ tcp spts:1024:65535 dpts:1:65535 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `int2ext:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `int2ext-default:' \end_layout \begin_layout Code 0 0 DROP tcp * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 DROP udp * * ::/0 ::/0 \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain intIN (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT all * * ::/0 \end_layout \begin_layout Code ¬ fe80::/ffc0:: \end_layout \begin_layout Code 4 384 ACCEPT all * * ::/0 ff02::/16 \end_layout \begin_layout Code \end_layout \begin_layout Code Chain intOUT (1 references) \end_layout \begin_layout Code pkts bytes target prot opt in out source destination \end_layout \begin_layout Code ¬ \end_layout \begin_layout Code 0 0 ACCEPT all * * ::/0 \end_layout \begin_layout Code ¬ fe80::/ffc0:: \end_layout \begin_layout Code 4 384 ACCEPT all * * ::/0 ff02::/16 \end_layout \begin_layout Code 0 0 LOG all * * ::/0 ::/0 \end_layout \begin_layout Code ¬ LOG flags 0 level 7 prefix `intOUT-default:' \end_layout \begin_layout Code 0 0 DROP all * * ::/0 ::/0 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "nat-netfilter6" \end_inset Network Address Translation (NAT) using netfilter6 \end_layout \begin_layout Standard Since at least Linux kernel version 3.9.0 and using ip6tables since 1.4.18 also Network Address Translation (NAT) is usable. \end_layout \begin_layout Subsection IPv6 Masquerading \end_layout \begin_layout Standard Like in IPv4 clients behind a router can be hided by using IPv6 masquerading (hide/overlap NAT), e.g. \end_layout \begin_layout Code # ip6tables -t nat -A POSTROUTING -o sixxs -s fec0::/64 -j MASQUERADE \end_layout \begin_layout Subsection IPv6 Destination NAT \end_layout \begin_layout Standard A dedicated public IPv6 address can be forwarded to an internal IPv6 address, e.g. \end_layout \begin_layout Code # ip6tables -t nat -A PREROUTING -d 2001:db8:0:1:5054:ff:fe01:2345 -i sixxs -j DNAT --to-destination fec0::5054:ff:fe01:2345 \end_layout \begin_layout Subsection IPv6 Port Forwarding \end_layout \begin_layout Standard A dedicated specified port can be forwarded to an internal system, e.g. \end_layout \begin_layout Code # ip6tables -t nat -A PREROUTING -i sixxs -p tcp --dport 8080 -j DNAT --to-desti nation [fec0::1234]:80 \end_layout \begin_layout Section Firewalling using nftables \end_layout \begin_layout Standard nftables adds in addition to protocol specific tables \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset (IPv4) and \begin_inset Quotes sld \end_inset ip6 \begin_inset Quotes srd \end_inset (IPv6) support for a IPv4/IPv6 aware table named \begin_inset Quotes sld \end_inset inet \begin_inset Quotes srd \end_inset . Using this table it's possible to add only one rule and match both protocols (in case of UDP and TCP). \end_layout \begin_layout Standard Take care if rules are contained in more than one table, because the tables are checked in sequence: \end_layout \begin_layout Code IPv4-Packet --> table "ip" --> table "inet" --> further checks \end_layout \begin_layout Code IPv6-Packet --> table "ip6" --> table "inet" --> further checks \end_layout \begin_layout Standard If table \begin_inset Quotes sld \end_inset ip6 \begin_inset Quotes srd \end_inset accepts the packet, also table \begin_inset Quotes sld \end_inset inet \begin_inset Quotes srd \end_inset must accept the packet, otherwise it can be dropped by a later drop rule. \end_layout \begin_layout Subsection Preparation for nftables usage \end_layout \begin_layout Standard Install a Linux distribution which has nftables support already included. At time of writing (May 2014) at least Fedora Rawhide (upcoming version 21) has support in conjunction with nftables version 0.2.0. \end_layout \begin_layout Subsection Basic nftables configuration \end_layout \begin_layout Standard Load kernel modules: \end_layout \begin_layout Code # modprobe nf_tables \end_layout \begin_layout Code # modprobe nf_tables_ipv4 \end_layout \begin_layout Code # modprobe nf_tables_ipv6 \end_layout \begin_layout Code # modprobe nf_tables_inet \end_layout \begin_layout Standard Flush iptables and ip6tables to avoid interferences: \end_layout \begin_layout Code # iptables -F \end_layout \begin_layout Code # ip6tables -F \end_layout \begin_layout Standard Create filter table: \end_layout \begin_layout Code # nft add table inet filter \end_layout \begin_layout Standard Create input chain: \end_layout \begin_layout Code # nft add chain inet filter input { type filter hook input priority 0 \backslash ; } \end_layout \begin_layout Subsection Simple filter policy with nftables using only table \begin_inset Quotes sld \end_inset inet \begin_inset Quotes srd \end_inset \end_layout \begin_layout Subsubsection Configuration \end_layout \begin_layout Standard Allow packets which are related to existing connection tracking entries \end_layout \begin_layout Code # nft add rule inet filter input ct state established,related counter accept \end_layout \begin_layout Standard Allow IPv4 and IPv6 ICMP echo-request (aka ping) \end_layout \begin_layout Code # nft add rule inet filter input meta nfproto ipv4 icmp type { echo-request } counter accept \end_layout \begin_layout Code # nft add rule inet filter input meta nfproto ipv6 icmpv6 type echo-request counter accept \end_layout \begin_layout Standard Allow some important IPv6 ICMP traffic, without counter, but checking hop-limit for security \end_layout \begin_layout Code # nft add rule inet filter input meta nfproto ipv6 \end_layout \begin_layout Code ¬ icmpv6 type { nd-neighbor-advert, nd-neighbor-solicit, nd-router-advert} ip6 hoplimit 1 accept \end_layout \begin_layout Code # nft add rule inet filter input meta nfproto ipv6 \end_layout \begin_layout Code ¬ icmpv6 type { nd-neighbor-advert, nd-neighbor-solicit, nd-router-advert} ip6 hoplimit 255 counter accept \end_layout \begin_layout Standard Allow incoming SSH for IPv4 and IPv6 \end_layout \begin_layout Code # nft add rule inet filter input tcp dport 22 ct state new tcp flags \backslash & \backslash (syn \backslash | ack \backslash ) == syn counter accept \end_layout \begin_layout Standard Reject/drop others \end_layout \begin_layout Code # nft add rule inet filter input tcp dport 0-65535 reject \end_layout \begin_layout Code # nft add rule inet filter input udp dport 0-65535 counter drop \end_layout \begin_layout Code # nft add rule inet filter input counter drop \end_layout \begin_layout Subsubsection Result \end_layout \begin_layout Standard Table for IP version aware filter \end_layout \begin_layout Code table inet filter { \end_layout \begin_layout Code chain input { \end_layout \begin_layout Code type filter hook input priority 0; \end_layout \begin_layout Code ct state established,related counter packets 0 bytes 0 accept \end_layout \begin_layout Code ip protocol icmp icmp type { echo-request} counter packets 0 bytes 0 accept \end_layout \begin_layout Code ip6 nexthdr ipv6-icmp icmpv6 type echo-request counter packets 0 bytes 0 accept \end_layout \begin_layout Code ip6 nexthdr ipv6-icmp ip6 hoplimit 1 icmpv6 type { nd-neighbor-advert, nd-neighbor-solicit, nd-router-advert} accept \end_layout \begin_layout Code ip6 nexthdr ipv6-icmp ip6 hoplimit 255 icmpv6 type { nd-neighbor-advert, nd-neighbor-solicit, nd-router-advert} accept \end_layout \begin_layout Code tcp dport ssh ct state new tcp flags & (syn | ack) == syn counter packets 0 bytes 0 accept \end_layout \begin_layout Code tcp dport >= 0 tcp dport <= 65535 counter packets 0 bytes 0 reject \end_layout \begin_layout Code udp dport >= 0 udp dport <= 65535 counter packets 0 bytes 0 drop \end_layout \begin_layout Code log prefix counter packets 0 bytes 0 drop \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Subsubsection Hints for logging \end_layout \begin_layout Standard To enable logging, an additonal kernel module must be loaded \end_layout \begin_layout Code # modprobe xt_LOG \end_layout \begin_layout Standard BUT TAKE CARE, IT LOOKS LIKE THAT NO LOG LEVEL CAN BE SPEFICIED CURRENTLY IN nftables, resulting that events are logged with kern.emerg - POSSIBILITY OF FLODDING THE CONSOLE WITH LOG ENTRIES! \end_layout \begin_layout Standard Fir initial test with logging it can be useful to disable kernel console logging in e.g. /etc/rsyslog.conf by putting a \begin_inset Quotes sld \end_inset # \begin_inset Quotes srd \end_inset in front of the related entry and restart logging daemon \end_layout \begin_layout Code #*.emerg :omusrmsg:* \end_layout \begin_layout Standard Rule from above accepting SSH on port 22, but now with logging: \end_layout \begin_layout Code # nft add rule inet filter input tcp dport 22 ct state new tcp flags \backslash & \backslash (syn \backslash | ack \backslash ) == syn log prefix \backslash "inet/input/accept: \backslash " counter accept \end_layout \begin_layout Subsection Filter policy with nftables using tables \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset , \begin_inset Quotes sld \end_inset ip6 \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset inet \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard As written above, if rules should be stored in related tables, it must be assured that earlier accepts are not discarded in the further table. This can be done using \begin_inset Quotes sld \end_inset meta mark set xxxx \begin_inset Quotes srd \end_inset on every accept rule and generic rules which accepts packets with \begin_inset Quotes sld \end_inset mark xxxx \begin_inset Quotes srd \end_inset . A resulting filter set would look like the following: \end_layout \begin_layout Code # for table in ip ip6 inet; do nft list table $table filter; done \end_layout \begin_layout Code table ip filter { \end_layout \begin_layout Code chain input { \end_layout \begin_layout Code type filter hook input priority 0; \end_layout \begin_layout Code ct state established,related counter packets 241 bytes 25193 accept \end_layout \begin_layout Code counter packets 2 bytes 120 mark 0x00000100 accept \end_layout \begin_layout Code icmp type { echo-request} counter packets 0 bytes 0 meta mark set 0x00000100 accept \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Code table ip6 filter { \end_layout \begin_layout Code chain input { \end_layout \begin_layout Code type filter hook input priority 0; \end_layout \begin_layout Code ct state established,related counter packets 14 bytes 4077 accept \end_layout \begin_layout Code counter packets 4 bytes 408 mark 0x00000100 accept \end_layout \begin_layout Code icmpv6 type echo-request counter packets 1 bytes 104 meta mark set 0x00000100 \end_layout \begin_layout Code icmpv6 type { nd-neighbor-advert, nd-neighbor-solicit, nd-router-advert} counter packets 2 bytes 224 meta mark set 0x00000100 accept \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Code table inet filter { \end_layout \begin_layout Code chain input { \end_layout \begin_layout Code type filter hook input priority 0; \end_layout \begin_layout Code ct state established,related counter packets 307 bytes 31974 accept \end_layout \begin_layout Code counter packets 6 bytes 528 mark 0x00000100 accept \end_layout \begin_layout Code tcp dport ssh ct state new tcp flags & (syn | ack) == syn log prefix "inet/input/accept: " meta mark set 0x00000100 counter packets 3 bytes 200 accept \end_layout \begin_layout Code log prefix "inet/input/reject: " counter packets 0 bytes 0 reject \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-security" \end_inset Security \end_layout \begin_layout Section Node security \end_layout \begin_layout Standard It's very recommended to apply all available patches and disable all not necessary services. Also bind services to the needed IPv4/IPv6 addresses only and install local firewalling. \end_layout \begin_layout Standard More to be filled... \end_layout \begin_layout Section Access limitations \end_layout \begin_layout Standard Many services uses the tcp_wrapper library for access control. Below is described the \begin_inset CommandInset ref LatexCommand ref name "use of tcp_wrapper" reference "hints-daemons-tcpwrapper" \end_inset . \end_layout \begin_layout Standard More to be filled... \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "IPv6-security-auditing" \end_inset IPv6 security auditing \end_layout \begin_layout Standard Currently there are no comfortable tools out which are able to check a system over network for IPv6 security issues. Neither \begin_inset CommandInset href LatexCommand href name "Nessus" target "http://www.nessus.org/" \end_inset nor any commercial security scanner is as far as I know able to scan IPv6 addresses. \end_layout \begin_layout Subsection Legal issues \end_layout \begin_layout Standard ATTENTION: always take care that you only scan your own systems or after receiving a written order, otherwise legal issues are able to come up to you. \begin_inset Newline newline \end_inset CHECK destination IPv6 addresses TWICE before starting a scan. \end_layout \begin_layout Subsection Security auditing using IPv6-enabled netcat \end_layout \begin_layout Standard With the IPv6-enabled netcat (see \begin_inset CommandInset href LatexCommand href name "IPv6+Linux-status-apps/security-auditing" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-apps.html#security-auditing" \end_inset for more) you can run a portscan by wrapping a script around which run through a port range, grab banners and so on. Usage example: \end_layout \begin_layout Code # nc6 ::1 daytime \end_layout \begin_layout Code 13 JUL 2002 11:22:22 CEST \end_layout \begin_layout Subsection Security auditing using IPv6-enabled nmap \end_layout \begin_layout Standard \begin_inset CommandInset href LatexCommand href name "NMap" target "http://www.insecure.org/nmap/" \end_inset , one of the best portscaner around the world, supports IPv6 since version 3.10ALPHA1. Usage example: \end_layout \begin_layout Code # nmap -6 -sT ::1 \end_layout \begin_layout Code Starting nmap V. 3.10ALPHA3 ( www.insecure.org/nmap/ ) \end_layout \begin_layout Code Interesting ports on localhost6 (::1): \end_layout \begin_layout Code (The 1600 ports scanned but not shown below are in state: closed) \end_layout \begin_layout Code Port State Service \end_layout \begin_layout Code 22/tcp open ssh \end_layout \begin_layout Code 53/tcp open domain \end_layout \begin_layout Code 515/tcp open printer \end_layout \begin_layout Code 2401/tcp open cvspserver \end_layout \begin_layout Code Nmap run completed -- 1 IP address (1 host up) scanned in 0.525 seconds \end_layout \begin_layout Subsection Security auditing using IPv6-enabled strobe \end_layout \begin_layout Standard Strobe is a (compared to NMap) more a low budget portscanner, but there is an IPv6-enabling patch available (see \begin_inset CommandInset href LatexCommand href name "IPv6+Linux-status-apps/security-auditing" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-apps.html#security-auditing" \end_inset for more). Usage example: \end_layout \begin_layout Code # ./strobe ::1 strobe 1.05 (c) 1995-1999 Julian Assange . \end_layout \begin_layout Code ::1 2401 unassigned unknown \end_layout \begin_layout Code ::1 22 ssh Secure Shell - RSA encrypted rsh \end_layout \begin_layout Code ::1 515 printer spooler (lpd) \end_layout \begin_layout Code ::1 6010 unassigned unknown \end_layout \begin_layout Code ::1 53 domain Domain Name Server \end_layout \begin_layout Standard Note: strobe isn't really developed further on, the shown version number isn't the right one. \end_layout \begin_layout Subsection Security auditing using online tools \end_layout \begin_layout Standard There are some IPv6 enabled online tools available which can support in testing inbound firewall configuration: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Tim's Online IPv6 TCP/UDP Port Scanner" target "http://ipv6.chappell-family.com/ipv6tcptest/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SubnetOnline IPv6 Scanner" target "http://www.subnetonline.com/pages/ipv6-network-tools/online-ipv6-port-scanner.php" \end_inset \end_layout \begin_layout Subsection Audit results \end_layout \begin_layout Standard If the result of an audit mismatch your IPv6 security policy, use IPv6 firewalli ng to close the holes, e.g. using netfilter6 (see \begin_inset CommandInset ref LatexCommand ref name "Firewalling/Netfilter6" reference "firewalling-netfilter6" \end_inset for more). \end_layout \begin_layout Standard Info: More detailed information concerning IPv6 Security can be found here: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IETF drafts - IPv6 Operations (v6ops)" target "http://www.ietf.org/ids.by.wg/v6ops.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3964 / Security Considerations for 6to4" target "http://www.faqs.org/rfcs/rfc3964.html" \end_inset \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-encryption-authentication" \end_inset Encryption and Authentication \end_layout \begin_layout Standard Unlike in IPv4, encryption and authentication is a mandatory feature of IPv6. Those features are normally implemented using IPsec (which can be also used by IPv4). \end_layout \begin_layout Section Modes of using encryption and authentication \end_layout \begin_layout Standard Two modes of encryption and authentication of a connection are possible: \end_layout \begin_layout Subsection Transport mode \end_layout \begin_layout Standard Transport mode is a real end-to-end connection mode. Here, only the payload (usually ICMP, TCP or UDP) is encrypted with their particular header, while the IP header is not encrypted (but usually included in authentication). \end_layout \begin_layout Standard Using AES-128 for encryption and SHA1 for authentication, this mode decreases the MTU by 42 octets. \end_layout \begin_layout Subsection Tunnel mode \end_layout \begin_layout Standard Tunnel mode can be used either for end-to-end or for gateway-to-gateway connection modes. Here, the complete IP packet is being encrypted and gets a new IP header prepended, all together constituing a new IP packet (this mechanism is also known as "encapsulation") \end_layout \begin_layout Standard This mode usually decreases the MTU by 40 octets from the MTU of transport mode. I.e. using AES-128 for encryption and SHA1 for authentication 82 octets less than the normal MTU. \end_layout \begin_layout Section Support in kernel (ESP and AH) \end_layout \begin_layout Subsection Support in vanilla Linux kernel 2.4.x \end_layout \begin_layout Standard At the time of writing missing in vanilla up to 2.4.28. There was an issue about keeping the Linux kernel source free of export/import- control-laws regarding encryption code. This is also one case why \begin_inset CommandInset href LatexCommand href name "FreeS/WAN project" target "http://www.freeswan.org/" \end_inset wasn't included in vanilla source. Perhaps a backport from 2.6.x will be done in the future. \end_layout \begin_layout Subsection Support in vanilla Linux kernel 2.6.x \end_layout \begin_layout Standard Current versions (as time of writing 2.6.9 and upper) support native IPsec for IPv4 and IPv6. \end_layout \begin_layout Standard Implementation was helped by the USAGI project. \end_layout \begin_layout Section Automatic key exchange (IKE) \end_layout \begin_layout Standard IPsec requires a key exchange of a secret. This is mostly done automatically by so called IKE daemons. They also handle the authentication of the peers, either by a common known secret (so called \begin_inset Quotes sld \end_inset pre-shared secret \begin_inset Quotes srd \end_inset ) or by RSA keys (which can also be used from X.509 certificates). \end_layout \begin_layout Standard Currently, two different IKE daemons are available for Linux, which totally differ in configuration and usage. \end_layout \begin_layout Standard I prefer \begin_inset Quotes sld \end_inset pluto \begin_inset Quotes srd \end_inset from the *S/WAN implementation because of the easier and one-config-only setup. \end_layout \begin_layout Subsection IKE daemon \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard The IKE daemon \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset is taken from the KAME project and ported to Linux. Modern Linux distributions contain this daemon in the package \begin_inset Quotes sld \end_inset ipsec-tools \begin_inset Quotes srd \end_inset . Two executables are required for a proper IPsec setup. Take a look on \begin_inset CommandInset href LatexCommand href name "Linux Advanced Routing & Traffic Control HOWTO / IPSEC" target "http://lartc.org/howto/lartc.ipsec.html" \end_inset , too. \end_layout \begin_layout Subsubsection Manipulation of the IPsec SA/SP database with the tool \begin_inset Quotes sld \end_inset setkey \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard \begin_inset Quotes sld \end_inset setkey \begin_inset Quotes srd \end_inset is important to define the security policy (SP) for the kernel. \end_layout \begin_layout Standard File: /etc/racoon/setkey.sh \end_layout \begin_layout Itemize Example for an end-to-end encrypted connection in transport mode \end_layout \begin_layout Code #!/sbin/setkey -f \end_layout \begin_layout Code flush; \end_layout \begin_layout Code spdflush; \end_layout \begin_layout Code spdadd 2001:db8:1:1::1 2001:db8:2:2::2 any -P out ipsec esp/transport//require; \end_layout \begin_layout Code spdadd 2001:db8:2:2::2 2001:db8:1:1::1 any -P in ipsec esp/transport//require; \end_layout \begin_layout Code \end_layout \begin_layout Itemize Example for a end-to-end encrypted connection in tunnel mode \end_layout \begin_layout Code #!/sbin/setkey -f \end_layout \begin_layout Code flush; \end_layout \begin_layout Code spdflush; \end_layout \begin_layout Code spdadd 2001:db8:1:1::1 2001:db8:2:2::2 any -P out ipsec \end_layout \begin_layout Code ¬ esp/tunnel/2001:db8:1:1::1-2001:db8:2:2::2/require; \end_layout \begin_layout Code spdadd 2001:db8:2:2::2 2001:db8:1:1::1 any -P in ipsec \end_layout \begin_layout Code ¬ esp/tunnel/2001:db8:2:2::2-2001:db8:1:1::1/require; \end_layout \begin_layout Standard For the other peer, you have to replace \begin_inset Quotes sld \end_inset in \begin_inset Quotes srd \end_inset with \begin_inset Quotes sld \end_inset out \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Subsubsection Configuration of the IKE daemon \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset requires a configuration file for proper execution. It includes the related settings to the security policy, which should be set up previously using \begin_inset Quotes sld \end_inset setkey \begin_inset Quotes srd \end_inset . \end_layout \begin_layout Standard File: /etc/racoon/racoon.conf \end_layout \begin_layout Code # Racoon IKE daemon configuration file. \end_layout \begin_layout Code # See 'man racoon.conf' for a description of the format and entries. \end_layout \begin_layout Code path include "/etc/racoon"; \end_layout \begin_layout Code path pre_shared_key "/etc/racoon/psk.txt"; \end_layout \begin_layout Code \end_layout \begin_layout Code listen \end_layout \begin_layout Code { \end_layout \begin_layout Code isakmp 2001:db8:1:1::1; \end_layout \begin_layout Code } \end_layout \begin_layout Code \end_layout \begin_layout Code remote 2001:db8:2:2::2 \end_layout \begin_layout Code { \end_layout \begin_layout Code exchange_mode main; \end_layout \begin_layout Code lifetime time 24 hour; \end_layout \begin_layout Code proposal \end_layout \begin_layout Code { \end_layout \begin_layout Code encryption_algorithm 3des; \end_layout \begin_layout Code hash_algorithm md5; \end_layout \begin_layout Code authentication_method pre_shared_key; \end_layout \begin_layout Code dh_group 2; \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Code \end_layout \begin_layout Code # gateway-to-gateway \end_layout \begin_layout Code sainfo address 2001:db8:1:1::1 any address 2001:db8:2:2::2 any \end_layout \begin_layout Code { \end_layout \begin_layout Code lifetime time 1 hour; \end_layout \begin_layout Code encryption_algorithm 3des; \end_layout \begin_layout Code authentication_algorithm hmac_md5; \end_layout \begin_layout Code compression_algorithm deflate; \end_layout \begin_layout Code } \end_layout \begin_layout Code \end_layout \begin_layout Code sainfo address 2001:db8:2:2::2 any address 2001:db8:1:1::1 any \end_layout \begin_layout Code { \end_layout \begin_layout Code lifetime time 1 hour; \end_layout \begin_layout Code encryption_algorithm 3des; \end_layout \begin_layout Code authentication_algorithm hmac_md5; \end_layout \begin_layout Code compression_algorithm deflate; \end_layout \begin_layout Code } \end_layout \begin_layout Standard Also set up the pre-shared secret: \end_layout \begin_layout Standard File: /etc/racoon/psk.txt \end_layout \begin_layout Code # file for pre-shared keys used for IKE authentication \end_layout \begin_layout Code # format is: 'identifier' 'key' \end_layout \begin_layout Code \end_layout \begin_layout Code 2001:db8:2:2::2 verysecret \end_layout \begin_layout Subsubsection Running IPsec with IKE daemon \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard At least the daemon needs to be started. For the first time, use debug and foreground mode. The following example shows a successful IKE phase 1 (ISAKMP-SA) and 2 (IPsec-SA) negotiation: \end_layout \begin_layout Code # racoon -F -v -f /etc/racoon/racoon.conf \end_layout \begin_layout Code Foreground mode. \end_layout \begin_layout Code 2005-01-01 20:30:15: INFO: @(#)ipsec-tools 0.3.3 \end_layout \begin_layout Code ¬ (http://ipsec-tools.sourceforge.net) \end_layout \begin_layout Code 2005-01-01 20:30:15: INFO: @(#)This product linked \end_layout \begin_layout Code ¬ OpenSSL 0.9.7a Feb 19 2003 (http://www.openssl.org/) \end_layout \begin_layout Code 2005-01-01 20:30:15: INFO: 2001:db8:1:1::1[500] used as isakmp port (fd=7) \end_layout \begin_layout Code 2005-01-01 20:31:06: INFO: IPsec-SA request for 2001:db8:2:2::2 \end_layout \begin_layout Code ¬ queued due to no phase1 found. \end_layout \begin_layout Code 2005-01-01 20:31:06: INFO: initiate new phase 1 negotiation: \end_layout \begin_layout Code ¬ 2001:db8:1:1::1[500]<=>2001:db8:2:2::2[500] \end_layout \begin_layout Code 2005-01-01 20:31:06: INFO: begin Identity Protection mode. \end_layout \begin_layout Code 2005-01-01 20:31:09: INFO: ISAKMP-SA established \end_layout \begin_layout Code ¬ 2001:db8:1:1::1[500]-2001:db8:2:2::2[500] spi:da3d3693289c9698:ac039a402b2db40 1 \end_layout \begin_layout Code 2005-01-01 20:31:09: INFO: initiate new phase 2 negotiation: \end_layout \begin_layout Code ¬ 2001:6f8:900:94::2[0]<=>2001:db8:2:2::2[0] \end_layout \begin_layout Code 2005-01-01 20:31:10: INFO: IPsec-SA established: \end_layout \begin_layout Code ¬ ESP/Tunnel 2001:db8:2:2::2->2001:db8:1:1::1 spi=253935531(0xf22bfab) \end_layout \begin_layout Code 2005-01-01 20:31:10: INFO: IPsec-SA established: \end_layout \begin_layout Code ¬ ESP/Tunnel 2001:db8:1:1::1->2001:db8:2:2::2 spi=175002564(0xa6e53c4) \end_layout \begin_layout Standard Each direction got its own IPsec-SA (like defined in the IPsec standard). With \begin_inset Quotes sld \end_inset tcpdump \begin_inset Quotes srd \end_inset on the related interface, you will see as result of an IPv6 ping: \end_layout \begin_layout Code 20:35:55.305707 2001:db8:1:1::1 > 2001:db8:2:2::2: ESP(spi=0x0a6e53c4,seq=0x3) \end_layout \begin_layout Code 20:35:55.537522 2001:db8:2:2::2 > 2001:db8:1:1::1: ESP(spi=0x0f22bfab,seq=0x3) \end_layout \begin_layout Standard As expected, the negotiated SPIs are being used here. \end_layout \begin_layout Standard And using \begin_inset Quotes sld \end_inset setkey \begin_inset Quotes srd \end_inset , current active parameters are shown: \end_layout \begin_layout Code # setkey -D \end_layout \begin_layout Code 2001:db8:1:1::1 2001:db8:2:2::2 \end_layout \begin_layout Code esp mode=tunnel spi=175002564(0x0a6e53c4) reqid=0(0x00000000) \end_layout \begin_layout Code E: 3des-cbc bd26bc45 aea0d249 ef9c6b89 7056080f 5d9fa49c 924e2edd \end_layout \begin_layout Code A: hmac-md5 60c2c505 517dd8b7 c9609128 a5efc2db \end_layout \begin_layout Code seq=0x00000000 replay=4 flags=0x00000000 state=mature \end_layout \begin_layout Code created: Jan 1 20:31:10 2005 current: Jan 1 20:40:47 2005 \end_layout \begin_layout Code diff: 577(s) hard: 3600(s) soft: 2880(s) \end_layout \begin_layout Code last: Jan 1 20:35:05 2005 hard: 0(s) soft: 0(s) \end_layout \begin_layout Code current: 540(bytes) hard: 0(bytes) soft: 0(bytes) \end_layout \begin_layout Code allocated: 3 hard: 0 soft: 0 \end_layout \begin_layout Code sadb_seq=1 pid=22358 refcnt=0 \end_layout \begin_layout Code 2001:db8:2:2::2 2001:db8:1:1::1 \end_layout \begin_layout Code esp mode=tunnel spi=253935531(0x0f22bfab) reqid=0(0x00000000) \end_layout \begin_layout Code E: 3des-cbc c1ddba65 83debd62 3f6683c1 20e747ac 933d203f 4777a7ce \end_layout \begin_layout Code A: hmac-md5 3f957db9 9adddc8c 44e5739d 3f53ca0e \end_layout \begin_layout Code seq=0x00000000 replay=4 flags=0x00000000 state=mature \end_layout \begin_layout Code created: Jan 1 20:31:10 2005 current: Jan 1 20:40:47 2005 \end_layout \begin_layout Code diff: 577(s) hard: 3600(s) soft: 2880(s) \end_layout \begin_layout Code last: Jan 1 20:35:05 2005 hard: 0(s) soft: 0(s) \end_layout \begin_layout Code current: 312(bytes) hard: 0(bytes) soft: 0(bytes) \end_layout \begin_layout Code allocated: 3 hard: 0 soft: 0 \end_layout \begin_layout Code sadb_seq=0 pid=22358 refcnt=0 \end_layout \begin_layout Subsection IKE daemon \begin_inset Quotes sld \end_inset pluto \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard The IKE daemon \begin_inset Quotes sld \end_inset pluto \begin_inset Quotes srd \end_inset is included in distributions of the *S/WAN projects. *S/WAN project starts at the beginning as \begin_inset CommandInset href LatexCommand href name "FreeS/WAN" target "http://www.freeswan.org/" \end_inset . Unfortunately, the FreeS/WAN project stopped further development in 2004. Because of the slow pace of development in the past, two spin-offs started: \begin_inset CommandInset href LatexCommand href name "strongSwan" target "http://www.strongswan.org/" \end_inset and \begin_inset CommandInset href LatexCommand href name "Openswan" target "http://www.openswan.org/" \end_inset . Today, readily installable packages are available for at least Openswan (included in Fedora Core 3). \end_layout \begin_layout Standard A major difference to \begin_inset Quotes sld \end_inset racoon \begin_inset Quotes srd \end_inset , only one configuration file is required. Also, an initscript exists for automatic setup after booting. \end_layout \begin_layout Subsubsection Configuration of the IKE daemon \begin_inset Quotes sld \end_inset pluto \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard The configuration is very similar to the IPv4 one, only one important option is necessary. \end_layout \begin_layout Standard File: /etc/ipsec.conf \end_layout \begin_layout Code # /etc/ipsec.conf - Openswan IPsec configuration file \end_layout \begin_layout Code # \end_layout \begin_layout Code # Manual: ipsec.conf.5 \end_layout \begin_layout Code version 2.0 # conforms to second version of ipsec.conf specification \end_layout \begin_layout Code \end_layout \begin_layout Code # basic configuration \end_layout \begin_layout Code config setup \end_layout \begin_layout Code # Debug-logging controls: "none" for (almost) none, "all" for lots. \end_layout \begin_layout Code # klipsdebug=none \end_layout \begin_layout Code # plutodebug="control parsing" \end_layout \begin_layout Code \end_layout \begin_layout Code #Disable Opportunistic Encryption \end_layout \begin_layout Code include /etc/ipsec.d/examples/no_oe.conf \end_layout \begin_layout Code \end_layout \begin_layout Code conn ipv6-p1-p2 \end_layout \begin_layout Code connaddrfamily=ipv6 # Important for IPv6, but no longer needed since StrongSwan 4 \end_layout \begin_layout Code left=2001:db8:1:1::1 \end_layout \begin_layout Code right=2001:db8:2:2::2 \end_layout \begin_layout Code authby=secret \end_layout \begin_layout Code esp=aes128-sha1 \end_layout \begin_layout Code ike=aes128-sha-modp1024 \end_layout \begin_layout Code type=transport \end_layout \begin_layout Code #type=tunnel \end_layout \begin_layout Code compress=no \end_layout \begin_layout Code #compress=yes \end_layout \begin_layout Code auto=add \end_layout \begin_layout Code #auto=up \end_layout \begin_layout Code \end_layout \begin_layout Standard Don't forget to define the pre-shared secret here also. \end_layout \begin_layout Standard File: /etc/ipsec.secrets \end_layout \begin_layout Code 2001:db8:1:1::1 2001:db8:2:2::2 : PSK "verysecret" \end_layout \begin_layout Subsubsection Running IPsec with IKE daemon \begin_inset Quotes sld \end_inset pluto \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard If installation of Openswan was successfully, an initscript should exist for starting IPsec, simply run (on each peer): \end_layout \begin_layout Code # /etc/rc.d/init.d/ipsec start \end_layout \begin_layout Standard Afterwards, start this connection on one peer. If you saw the line \begin_inset Quotes sld \end_inset IPsec SA established \begin_inset Quotes srd \end_inset , all worked fine. \end_layout \begin_layout Code # ipsec auto --up ipv6-peer1-peer2 \end_layout \begin_layout Code 104 "ipv6-p1-p2" #1: STATE_MAIN_I1: initiate \end_layout \begin_layout Code 106 "ipv6-p1-p2" #1: STATE_MAIN_I2: sent MI2, expecting MR2 \end_layout \begin_layout Code 108 "ipv6-p1-p2" #1: STATE_MAIN_I3: sent MI3, expecting MR3 \end_layout \begin_layout Code 004 "ipv6-p1-p2" #1: STATE_MAIN_I4: ISAKMP SA established \end_layout \begin_layout Code 112 "ipv6-p1-p2" #2: STATE_QUICK_I1: initiate \end_layout \begin_layout Code 004 "ipv6-p1-p2" #2: STATE_QUICK_I2: sent QI2, \end_layout \begin_layout Code ¬ IPsec SA established {ESP=>0xa98b7710 <0xa51e1f22} \end_layout \begin_layout Standard Because *S/WAN and setkey/racoon do use the same IPsec implementation in Linux 2.6.x kernel, \begin_inset Quotes sld \end_inset setkey \begin_inset Quotes srd \end_inset can be used here too to show current active parameters: \end_layout \begin_layout Code # setkey -D \end_layout \begin_layout Code 2001:db8:1:1::1 2001:db8:2:2::2 \end_layout \begin_layout Code esp mode=transport spi=2844489488(0xa98b7710) reqid=16385(0x00004001) \end_layout \begin_layout Code E: aes-cbc 082ee274 2744bae5 7451da37 1162b483 \end_layout \begin_layout Code A: hmac-sha1 b7803753 757417da 477b1c1a 64070455 ab79082c \end_layout \begin_layout Code seq=0x00000000 replay=64 flags=0x00000000 state=mature \end_layout \begin_layout Code created: Jan 1 21:16:32 2005 current: Jan 1 21:22:20 2005 \end_layout \begin_layout Code diff: 348(s) hard: 0(s) soft: 0(s) \end_layout \begin_layout Code last: hard: 0(s) soft: 0(s) \end_layout \begin_layout Code current: 0(bytes) hard: 0(bytes) soft: 0(bytes) \end_layout \begin_layout Code allocated: 0 hard: 0 soft: 0 \end_layout \begin_layout Code sadb_seq=1 pid=23825 refcnt=0 \end_layout \begin_layout Code 2001:db8:2:2::2 2001:db8:1:1::1 \end_layout \begin_layout Code esp mode=transport spi=2770214690(0xa51e1f22) reqid=16385(0x00004001) \end_layout \begin_layout Code E: aes-cbc 6f59cc30 8d856056 65e07b76 552cac18 \end_layout \begin_layout Code A: hmac-sha1 c7c7d82b abfca8b1 5440021f e0c3b335 975b508b \end_layout \begin_layout Code seq=0x00000000 replay=64 flags=0x00000000 state=mature \end_layout \begin_layout Code created: Jan 1 21:16:31 2005 current: Jan 1 21:22:20 2005 \end_layout \begin_layout Code diff: 349(s) hard: 0(s) soft: 0(s) \end_layout \begin_layout Code last: hard: 0(s) soft: 0(s) \end_layout \begin_layout Code current: 0(bytes) hard: 0(bytes) soft: 0(bytes) \end_layout \begin_layout Code allocated: 0 hard: 0 soft: 0 \end_layout \begin_layout Code sadb_seq=0 pid=23825 refcnt=0 \end_layout \begin_layout Section Additional informations: \end_layout \begin_layout Standard On Linux Kernel 2.6.x you can get the policy and status of IPsec also using \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset : \end_layout \begin_layout Code # ip xfrm policy \end_layout \begin_layout Code ... \end_layout \begin_layout Code \end_layout \begin_layout Code # ip xfrm state \end_layout \begin_layout Code ... \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-qos" \end_inset Quality of Service (QoS) \end_layout \begin_layout Standard IPv6 supports QoS with use of Flow Labels and Traffic Classes. \end_layout \begin_layout Standard Additional infos: \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "RFC 3697 / IPv6 Flow Label Specification" target "http://www.faqs.org/rfcs/rfc3697.html" \end_inset \end_layout \begin_layout Section General \end_layout \begin_layout Standard Proper working QoS is only possible on the outgoing interface of a router or host, where the bottleneck begins. Everything else is a hickup and not subject to work as expected or has a successful result. \end_layout \begin_layout Code -------------->------- \end_layout \begin_layout Code Queue 1 \backslash \end_layout \begin_layout Code --->--- ---->--------->--------->--------------- \end_layout \begin_layout Code Big pipe Queue 2 Queue 1 / Queue 2 / Queue 3 Thin Pipe \end_layout \begin_layout Code --->---- ---->--------->--------->--------------- \end_layout \begin_layout Code Queue 3 / \end_layout \begin_layout Code -------------->------- \end_layout \begin_layout Section Linux QoS using \begin_inset Quotes sld \end_inset tc \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard Linux is using \begin_inset Quotes sld \end_inset tc \begin_inset Quotes srd \end_inset from the \begin_inset Quotes sld \end_inset iproute2 \begin_inset Quotes srd \end_inset package to configure traffic shaping, generally described in the \begin_inset CommandInset href LatexCommand href name "Linux Advanced Routing & Traffic Control HOWTO" target "http://lartc.org/" \end_inset . \end_layout \begin_layout Subsection Example for a constant bitrate queuing \end_layout \begin_layout Standard With the \begin_inset Quotes sld \end_inset cbq \begin_inset Quotes srd \end_inset scheduler, pipes with constant bit rates can be defined. \end_layout \begin_layout Subsubsection Root qdisc definition \end_layout \begin_layout Standard Define root qdisc with a bandwidth of 1000 MBit/s on eth1 \end_layout \begin_layout Code # tc qdisc add dev eth1 root handle 1: cbq avpkt 1000 bandwidth 1000Mbit \end_layout \begin_layout Subsubsection QoS class definition \end_layout \begin_layout Standard Define a class 1:1 with 1 MBit/s \end_layout \begin_layout Code # tc class add dev eth1 parent 1: classid 1:1 cbq rate 1Mbit allot 1500 bounded \end_layout \begin_layout Standard Define a class 1:2 with 50 MBit/s \end_layout \begin_layout Code # tc class add dev eth1 parent 1: classid 1:2 cbq rate 50Mbit allot 1500 bounded \end_layout \begin_layout Standard Define a class 1:3 with 10 MBit/s \end_layout \begin_layout Code # tc class add dev eth1 parent 1: classid 1:3 cbq rate 10Mbit allot 1500 bounded \end_layout \begin_layout Standard Define a class 1:4 with 200 kBit/s \end_layout \begin_layout Code # tc class add dev eth1 parent 1: classid 1:4 cbq rate 200kbit allot 1500 bounded \end_layout \begin_layout Subsubsection QoS filter definition \end_layout \begin_layout Standard Define a filter for IPv4 ( \emph on protocol ip \emph default ), TCP ( \emph on match ip protocol 6 0xff \emph default ) destination port 5001 ( \emph on match ip dport 5001 0xffff \emph default ) using class 1:2 from above \end_layout \begin_layout Code # tc filter add dev eth1 parent 1: protocol ip u32 match ip protocol 6 0xff match ip dport 5001 0xffff flowid 1:1 \end_layout \begin_layout Standard Define a filter for IPv6 ( \emph on protocol ip \emph default ), TCP ( \emph on match ip6 protocol 6 0xff \emph default ) destination port 5001 using class 1:2 from above \end_layout \begin_layout Code # tc filter add dev eth1 parent 1: protocol ipv6 u32 match ip6 protocol 6 0xff match ip6 dport 5001 0xffff flowid 1:2 \end_layout \begin_layout Standard Define a filter for IPv6 for packets having flow label 12345 ( \emph on match ip6 flowlabel 12345 0x3ffff \emph default ) using class 1:3 from above \end_layout \begin_layout Code # tc filter add dev eth1 parent 1: protocol ipv6 u32 match ip6 flowlabel 12345 0x3ffff flowid 1:3 \end_layout \begin_layout Standard Define a filter for IPv6 for packets having Linux iptables mark 32 ( \emph on handle 32 fw \emph default ) specified using class 1:4 from above \end_layout \begin_layout Code # tc filter add dev eth1 parent 1: protocol ipv6 handle 32 fw flowid 1:4 \end_layout \begin_layout Standard The last filter definition requires an entry in the ip6tables to mark a packet \end_layout \begin_layout Code # ip6tables -A POSTROUTING -t mangle -p tcp --dport 5003 -j MARK --set-mark 32 \end_layout \begin_layout Subsubsection Testing filter definitions using iperf \end_layout \begin_layout Standard Start on server side each one one separate console: \end_layout \begin_layout Code # iperf -V -s -p 5001 \end_layout \begin_layout Code # iperf -V -s -p 5002 \end_layout \begin_layout Code # iperf -V -s -p 5003 \end_layout \begin_layout Standard Start on client side and compare results: \end_layout \begin_layout Code # iperf -V -c SERVER-IPv4 -p 5001 (expected: 1 MBit/s) \end_layout \begin_layout Code # iperf -V -c SERVER-IPv6 -p 5001 (expected: 50 MBit/s) \end_layout \begin_layout Code # iperf -V -c SERVER-IPv4 -p 5002 (expected: >> 50 MBit/s && <= 1000 MBit/s) \end_layout \begin_layout Code # iperf -V -c SERVER-IPv6 -p 5002 (expected: >> 50 MBit/s && <= 1000 MBit/s) \end_layout \begin_layout Code # iperf -V -c SERVER-IPv4 -p 5003 (expected: >> 50 MBit/s && <= 1000 MBit/s) \end_layout \begin_layout Code # iperf -V -c SERVER-IPv6 -p 5003 (expected: 200 kBit/s) \end_layout \begin_layout Standard The rate result should be as defined in the classes (see above), the results on port 5002 should be very similar independend from used IP version. \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-hints-daemons" \end_inset Hints for IPv6-enabled daemons \end_layout \begin_layout Standard Here some hints are shown for IPv6-enabled daemons. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-bind" \end_inset Berkeley Internet Name Domain (BIND) daemon \begin_inset Quotes sld \end_inset named \begin_inset Quotes srd \end_inset \end_layout \begin_layout Standard IPv6 is supported since version 9. Always use newest available version. At least version 9.1.3 must be used, older versions can contain remote exploitabl e security holes. \end_layout \begin_layout Subsection Listening on IPv6 addresses \end_layout \begin_layout Standard Note: unlike in IPv4 current versions doesn't allow to bind a server socket to dedicated IPv6 addresses, so only \emph on any \emph default or \emph on none \emph default are valid. Because this can be a security issue, check the Access Control List (ACL) section below, too! \end_layout \begin_layout Subsubsection Enable BIND named for listening on IPv6 address \end_layout \begin_layout Standard To enable IPv6 for listening, following options are requested to change \end_layout \begin_layout Code options { \end_layout \begin_layout Code # sure other options here, too \end_layout \begin_layout Code listen-on-v6 { any; }; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard This should result after restart in e.g. \end_layout \begin_layout Code # netstat -lnptu |grep "named \backslash W*$" \end_layout \begin_layout Code tcp 0 0 :::53 :::* LISTEN 1234/named \end_layout \begin_layout Code ¬ # incoming TCP requests \end_layout \begin_layout Code udp 0 0 1.2.3.4:53 0.0.0.0:* 1234/named \end_layout \begin_layout Code ¬ # incoming UDP requests to IPv4 1.2.3.4 \end_layout \begin_layout Code udp 0 0 127.0.0.1:53 0.0.0.0:* 1234/named \end_layout \begin_layout Code ¬ # incoming UDP requests to IPv4 localhost \end_layout \begin_layout Code udp 0 0 0.0.0.0:32868 0.0.0.0:* 1234/named \end_layout \begin_layout Code ¬ # dynamic chosen port for outgoing queries \end_layout \begin_layout Code udp 0 0 :::53 :::* 1234/named \end_layout \begin_layout Code ¬ # incoming UDP request to any IPv6 \end_layout \begin_layout Standard And a simple test looks like \end_layout \begin_layout Code # dig localhost @::1 \end_layout \begin_layout Standard and should show you a result. \end_layout \begin_layout Subsubsection Disable BIND named for listening on IPv6 address \end_layout \begin_layout Standard To disable IPv6 for listening, following options are requested to change \end_layout \begin_layout Code options { \end_layout \begin_layout Code # sure other options here, too \end_layout \begin_layout Code listen-on-v6 { none; }; \end_layout \begin_layout Code }; \end_layout \begin_layout Subsection IPv6 enabled Access Control Lists (ACL) \end_layout \begin_layout Standard IPv6 enabled ACLs are possible and should be used whenever it's possible. An example looks like following: \end_layout \begin_layout Code acl internal-net { \end_layout \begin_layout Code 127.0.0.1; \end_layout \begin_layout Code 1.2.3.0/24; \end_layout \begin_layout Code 2001:0db8:100::/56; \end_layout \begin_layout Code ::1/128; \end_layout \begin_layout Code ::ffff:1.2.3.4/128; \end_layout \begin_layout Code }; \end_layout \begin_layout Code acl ns-internal-net { \end_layout \begin_layout Code 1.2.3.4; \end_layout \begin_layout Code 1.2.3.5; \end_layout \begin_layout Code 2001:0db8:100::4/128; \end_layout \begin_layout Code 2001:0db8:100::5/128; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard This ACLs can be used e.g. for queries of clients and transfer zones to secondary name-servers. This prevents also your caching name-server to be used from outside using IPv6. \end_layout \begin_layout Code options { \end_layout \begin_layout Code # sure other options here, too \end_layout \begin_layout Code listen-on-v6 { none; }; \end_layout \begin_layout Code allow-query { internal-net; }; \end_layout \begin_layout Code allow-transfer { ns-internal-net; }; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard It's also possible to set the \emph on allow-query \emph default and \emph on allow-transfer \emph default option for most of single zone definitions, too. \end_layout \begin_layout Subsection Sending queries with dedicated IPv6 address \end_layout \begin_layout Standard This option is not required, but perhaps needed: \end_layout \begin_layout Code query-source-v6 address port ; \end_layout \begin_layout Subsection Per zone defined dedicated IPv6 addresses \end_layout \begin_layout Standard It's also possible to define per zone some IPv6 addresses. \end_layout \begin_layout Subsubsection Transfer source address \end_layout \begin_layout Standard Transfer source address is used for outgoing zone transfers: \end_layout \begin_layout Code transfer-source-v6 [port port]; \end_layout \begin_layout Subsubsection Notify source address \end_layout \begin_layout Standard Notify source address is used for outgoing notify messages: \end_layout \begin_layout Code notify-source-v6 [port port]; \end_layout \begin_layout Subsection IPv6 DNS zone files examples \end_layout \begin_layout Standard Some information can be also found at \begin_inset CommandInset href LatexCommand href name "IPv6 DNS Setup Information (article)" target "http://www.isi.edu/~bmanning/v6DNS.html" \end_inset . Perhaps also helpful is the \begin_inset CommandInset href LatexCommand href name "IPv6 Reverse DNS zone builder for BIND 8/9 (webtool)" target "http://tools.fpsn.net/ipv6-inaddr/" \end_inset . \end_layout \begin_layout Subsection Serving IPv6 related DNS data \end_layout \begin_layout Standard For IPv6 new types and root zones for reverse lookups are defined: \end_layout \begin_layout Itemize AAAA and reverse IP6.INT: specified in \begin_inset CommandInset href LatexCommand href name "RFC 1886 / DNS Extensions to support IP version 6" target "http://www.faqs.org/rfcs/rfc1886.html" \end_inset , usable since BIND version 4.9.6 \end_layout \begin_layout Itemize A6, DNAME (DEPRECATED NOW!) and reverse IP6.ARPA: specified in \begin_inset CommandInset href LatexCommand href name "RFC 2874 / DNS Extensions to Support IPv6 Address Aggregation and Renumbering" target "http://www.faqs.org/rfcs/rfc2874.html" \end_inset , usable since BIND 9, but see also an information about the current state at \begin_inset CommandInset href LatexCommand href name "Domain Name System Extension (dnsext)" target "http://www.ietf.org/ids.by.wg/dnsext.html" \end_inset \end_layout \begin_layout Standard Perhaps filled later more content, for the meantime take a look at given RFCs and \end_layout \begin_layout Itemize AAAA and reverse IP6.INT: \begin_inset CommandInset href LatexCommand href name "IPv6 DNS Setup Information" target "http://www.isi.edu/~bmanning/v6DNS.html" \end_inset \end_layout \begin_layout Itemize A6, DNAME (DEPRECATED NOW!) and reverse IP6.ARPA: take a look into chapter 4 and 6 of the BIND 9 Administrator Reference Manual (ARM) distributed with the bind-package or get this here: \begin_inset CommandInset href LatexCommand href name "BIND manual version 9.3" target "http://www.isc.org/sw/bind/arm93/" \end_inset \end_layout \begin_layout Standard Because IP6.INT is deprecated (but still in use), a DNS server which will support IPv6 information has to serve both reverse zones. \end_layout \begin_layout Subsubsection Current best practice \end_layout \begin_layout Standard Because there are some troubles around using the new formats, current best practice is: \end_layout \begin_layout Standard Forward lookup support: \end_layout \begin_layout Itemize AAAA \end_layout \begin_layout Standard Reverse lookup support: \end_layout \begin_layout Itemize Reverse nibble format for zone ip6.int (FOR BACKWARD COMPATIBILITY) \end_layout \begin_layout Itemize Reverse nibble format for zone ip6.arpa (RECOMMENDED) \end_layout \begin_layout Subsection Checking IPv6-enabled connect \end_layout \begin_layout Standard To check, whether BIND named is listening on an IPv6 socket and serving data see following examples. \end_layout \begin_layout Subsubsection IPv6 connect, but denied by ACL \end_layout \begin_layout Standard Specifying a dedicated server for the query, an IPv6 connect can be forced: \end_layout \begin_layout Code $ host -t aaaa www.6bone.net 2001:0db8:200:f101::1 \end_layout \begin_layout Code Using domain server: \end_layout \begin_layout Code Name: 2001:0db8:200:f101::1 \end_layout \begin_layout Code Address: 2001:0db8:200:f101::1#53 \end_layout \begin_layout Code Aliases: \end_layout \begin_layout Code \end_layout \begin_layout Code Host www.6bone.net. not found: 5(REFUSED) \end_layout \begin_layout Standard Related log entry looks like following: \end_layout \begin_layout Code Jan 3 12:43:32 gate named[12347]: client \end_layout \begin_layout Code ¬ 2001:0db8:200:f101:212:34ff:fe12:3456#32770: \end_layout \begin_layout Code query denied \end_layout \begin_layout Standard If you see such entries in the log, check whether requests from this client should be allowed and perhaps review your ACL configuration. \end_layout \begin_layout Subsubsection Successful IPv6 connect \end_layout \begin_layout Standard A successful IPv6 connect looks like following: \end_layout \begin_layout Code $ host -t aaaa www.6bone.net 2001:0db8:200:f101::1 \end_layout \begin_layout Code Using domain server: \end_layout \begin_layout Code Name: 2001:0db8:200:f101::1 \end_layout \begin_layout Code Address: 2001:0db8:200:f101::1#53 \end_layout \begin_layout Code Aliases: \end_layout \begin_layout Code \end_layout \begin_layout Code www.6bone.net. is an alias for 6bone.net. \end_layout \begin_layout Code 6bone.net. has AAAA address 3ffe:b00:c18:1::10 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-xinetd" \end_inset Internet super daemon (xinetd) \end_layout \begin_layout Standard IPv6 is supported since \begin_inset CommandInset href LatexCommand href name "xinetd" target "http://www.xinetd.org/" \end_inset version around 1.8.9. Always use newest available version. At least version 2.3.3 must be used, older versions can contain remote exploitabl e security holes. \end_layout \begin_layout Standard Some Linux distribution contain an extra package for the IPv6 enabled xinetd, some others start the IPv6-enabled xinetd if following variable is set: NETWORKING_IPV6="yes", mostly done by /etc/sysconfig/network (only valid for Red Hat like distributions). In newer releases, one binary supports IPv4 and IPv6. \end_layout \begin_layout Standard If you enable a built-in service like e.g. daytime by modifying the configuration file in /etc/xinetd.d/daytime like \end_layout \begin_layout Code # diff -u /etc/xinetd.d/daytime.orig /etc/xinetd.d/daytime \end_layout \begin_layout Code --- /etc/xinetd.d/daytime.orig Sun Dec 16 19:00:14 2001 \end_layout \begin_layout Code +++ /etc/xinetd.d/daytime Sun Dec 16 19:00:22 2001 \end_layout \begin_layout Code @@ -10,5 +10,5 @@ \end_layout \begin_layout Code protocol = tcp \end_layout \begin_layout Code user = root \end_layout \begin_layout Code wait = no \end_layout \begin_layout Code - disable = yes \end_layout \begin_layout Code + disable = no \end_layout \begin_layout Code } \end_layout \begin_layout Standard After restarting the xinetd you should get a positive result like: \end_layout \begin_layout Code # netstat -lnptu -A inet6 |grep "xinetd*" \end_layout \begin_layout Code tcp 0 0 ::ffff:192.168.1.1:993 :::* LISTEN 12345/xinetd-ipv6 \end_layout \begin_layout Code tcp 0 0 :::13 :::* LISTEN 12345/xinetd-ipv6 <- service \end_layout \begin_layout Code ¬ daytime/tcp \end_layout \begin_layout Code tcp 0 0 ::ffff:192.168.1.1:143 :::* LISTEN 12345/xinetd-ipv6 \end_layout \begin_layout Standard Shown example also displays an IMAP and IMAP-SSL IPv4-only listening xinetd. \end_layout \begin_layout Standard Note: earlier versions had a problem that an IPv4-only xinetd won't start on an IPv6-enabled node and also the IPv6-enabled xinetd won't start on an IPv4-only node. This is known to be fixed in later versions, at least version 2.3.11. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-apache2" \end_inset Webserver Apache2 (httpd2) \end_layout \begin_layout Standard Apache web server supports IPv6 native by maintainers since 2.0.14. Available patches for the older 1.3.x series are not current and shouldn't be used in public environment, but available at \begin_inset CommandInset href LatexCommand href name "KAME / Misc" target "ftp://ftp.kame.net/pub/kame/misc/" \end_inset . \end_layout \begin_layout Subsection Listening on IPv6 addresses \end_layout \begin_layout Standard Note: virtual hosts on IPv6 addresses are broken in versions until 2.0.28 (a patch is available for 2.0.28). But always try latest available version first because earlier versions had some security issues. \end_layout \begin_layout Subsubsection Virtual host listen on an IPv6 address only \end_layout \begin_layout Code Listen [2001:0db8:100::1]:80 \end_layout \begin_layout Code \end_layout \begin_layout Code ServerName ipv6only.yourdomain.yourtopleveldomain \end_layout \begin_layout Code # ...sure more config lines \end_layout \begin_layout Code \end_layout \begin_layout Subsubsection Virtual host listen on an IPv6 and on an IPv4 address \end_layout \begin_layout Code Listen [2001:0db8:100::2]:80 \end_layout \begin_layout Code Listen 1.2.3.4:80 \end_layout \begin_layout Code \end_layout \begin_layout Code ServerName ipv6andipv4.yourdomain.yourtopleveldomain \end_layout \begin_layout Code # ...sure more config lines \end_layout \begin_layout Code \end_layout \begin_layout Standard This should result after restart in e.g. \end_layout \begin_layout Code # netstat -lnptu |grep "httpd2 \backslash W*$" \end_layout \begin_layout Code tcp 0 0 1.2.3.4:80 0.0.0.0:* LISTEN 12345/httpd2 \end_layout \begin_layout Code tcp 0 0 2001:0db8:100::1:80 :::* LISTEN 12345/httpd2 \end_layout \begin_layout Code tcp 0 0 2001:0db8:100::2:80 :::* LISTEN 12345/httpd2 \end_layout \begin_layout Standard For simple tests use the telnet example already shown. \end_layout \begin_layout Subsubsection Additional notes \end_layout \begin_layout Itemize Apache2 supports a method called \begin_inset Quotes sld \end_inset sendfile \begin_inset Quotes srd \end_inset to speedup serving data. Some NIC drivers also support offline checksumming. In some cases, this can lead to connection problems and invalid TCP checksums. In this cases, disable \begin_inset Quotes sld \end_inset sendfile \begin_inset Quotes srd \end_inset either by recompiling using configure option \begin_inset Quotes sld \end_inset --without-sendfile \begin_inset Quotes srd \end_inset or by using the "EnableSendfile off" directive in configuration file. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-radvd" \end_inset Router Advertisement Daemon (radvd) \end_layout \begin_layout Standard The router advertisement daemon is very useful on a LAN, if clients should be auto-configured. The daemon itself should run on the Linux default IPv6 gateway router (it's not required that this is also the default IPv4 gateway, so pay attention who on your LAN is sending router advertisements). \end_layout \begin_layout Standard You can specify some information and flags which should be contained in the advertisement. Common used are \end_layout \begin_layout Itemize Prefix (needed) \end_layout \begin_layout Itemize Lifetime of the prefix \end_layout \begin_layout Itemize Frequency of sending advertisements (optional) \end_layout \begin_layout Standard After a proper configuration, the daemon sends advertisements through specified interfaces and clients are hopefully receive them and auto-magically configure addresses with received prefix and the default route. \end_layout \begin_layout Subsection Configuring radvd \end_layout \begin_layout Subsubsection Simple configuration \end_layout \begin_layout Standard Radvd's config file is normally /etc/radvd.conf. An simple example looks like following: \end_layout \begin_layout Code interface eth0 { \end_layout \begin_layout Code AdvSendAdvert on; \end_layout \begin_layout Code MinRtrAdvInterval 3; \end_layout \begin_layout Code MaxRtrAdvInterval 10; \end_layout \begin_layout Code prefix 2001:0db8:0100:f101::/64 { \end_layout \begin_layout Code AdvOnLink on; \end_layout \begin_layout Code AdvAutonomous on; \end_layout \begin_layout Code AdvRouterAddr on; \end_layout \begin_layout Code }; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard This results on client side in \end_layout \begin_layout Code # ip -6 addr show eth0 \end_layout \begin_layout Code 3: eth0: mtu 1500 qdisc pfifo_fast qlen 100 \end_layout \begin_layout Code inet6 2001:0db8:100:f101:2e0:12ff:fe34:1234/64 scope global dynamic \end_layout \begin_layout Code valid_lft 2591992sec preferred_lft 604792sec \end_layout \begin_layout Code inet6 fe80::2e0:12ff:fe34:1234/10 scope link \end_layout \begin_layout Standard Because no lifetime was defined, a very high value was used. \end_layout \begin_layout Subsubsection Special 6to4 configuration \end_layout \begin_layout Standard Version since 0.6.2pl3 support the automatic (re)-generation of the prefix depending on an IPv4 address of a specified interface. This can be used to distribute advertisements in a LAN after the 6to4 tunneling has changed. Mostly used behind a dynamic dial-on-demand Linux router. Because of the sure shorter lifetime of such prefix (after each dial-up, another prefix is valid), the lifetime configured to minimal values: \end_layout \begin_layout Code interface eth0 { \end_layout \begin_layout Code AdvSendAdvert on; \end_layout \begin_layout Code MinRtrAdvInterval 3; \end_layout \begin_layout Code MaxRtrAdvInterval 10; \end_layout \begin_layout Code prefix 0:0:0:f101::/64 { \end_layout \begin_layout Code AdvOnLink off; \end_layout \begin_layout Code AdvAutonomous on; \end_layout \begin_layout Code AdvRouterAddr on; \end_layout \begin_layout Code Base6to4Interface ppp0; \end_layout \begin_layout Code AdvPreferredLifetime 20; \end_layout \begin_layout Code AdvValidLifetime 30; \end_layout \begin_layout Code }; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard This results on client side in (assuming, ppp0 has currently 1.2.3.4 as local IPv4 address): \end_layout \begin_layout Code # /sbin/ip -6 addr show eth0 \end_layout \begin_layout Code 3: eth0: mtu 1500 qdisc pfifo_fast qlen 100 \end_layout \begin_layout Code inet6 2002:0102:0304:f101:2e0:12ff:fe34:1234/64 scope global dynamic \end_layout \begin_layout Code valid_lft 22sec preferred_lft 12sec \end_layout \begin_layout Code inet6 fe80::2e0:12ff:fe34:1234/10 scope link \end_layout \begin_layout Standard Because a small lifetime was defined, such prefix will be thrown away quickly, if no related advertisement was received. \end_layout \begin_layout Standard Additional note: if you do not used special 6to4 support in initscripts, you have to setup a special route on the internal interface on the router, otherwise you will get some backrouting problems. for the example showh here: \end_layout \begin_layout Code # /sbin/ip -6 route add 2002:0102:0304:f101::/64 dev eth0 metric 1 \end_layout \begin_layout Standard This route needs to be replaced every time the prefix changes, which is the case after a new IPv4 address was assigned to the dial-up interface. \end_layout \begin_layout Subsection Debugging \end_layout \begin_layout Standard A program called \begin_inset Quotes sld \end_inset radvdump \begin_inset Quotes srd \end_inset can help you looking into sent or received advertisements. Simple to use: \end_layout \begin_layout Code # radvdump \end_layout \begin_layout Code Router advertisement from fe80::280:c8ff:feb9:cef9 (hoplimit 255) \end_layout \begin_layout Code AdvCurHopLimit: 64 \end_layout \begin_layout Code AdvManagedFlag: off \end_layout \begin_layout Code AdvOtherConfigFlag: off \end_layout \begin_layout Code AdvHomeAgentFlag: off \end_layout \begin_layout Code AdvReachableTime: 0 \end_layout \begin_layout Code AdvRetransTimer: 0 \end_layout \begin_layout Code Prefix 2002:0102:0304:f101::/64 \end_layout \begin_layout Code AdvValidLifetime: 30 \end_layout \begin_layout Code AdvPreferredLifetime: 20 \end_layout \begin_layout Code AdvOnLink: off \end_layout \begin_layout Code AdvAutonomous: on \end_layout \begin_layout Code AdvRouterAddr: on \end_layout \begin_layout Code Prefix 2001:0db8:100:f101::/64 \end_layout \begin_layout Code AdvValidLifetime: 2592000 \end_layout \begin_layout Code AdvPreferredLifetime: 604800 \end_layout \begin_layout Code AdvOnLink: on \end_layout \begin_layout Code AdvAutonomous: on \end_layout \begin_layout Code AdvRouterAddr: on \end_layout \begin_layout Code AdvSourceLLAddress: 00 80 12 34 56 78 \end_layout \begin_layout Standard Output shows you each advertisement package in readable format. You should see your configured values here again, if not, perhaps it's not your radvd which sends the advertisement...look for another router on the link (and take the LLAddress, which is the MAC address for tracing). \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-dhcpv6" \end_inset Dynamic Host Configuration v6 Server (dhcp6s) \end_layout \begin_layout Standard DHCPv6 can be used for stateful configurations. The daemon itself need not necessary run on the Linux default IPv6 gateway router. \end_layout \begin_layout Standard You can specify more information than by using radvd. The are most similar to IPv4 DHCP server. \end_layout \begin_layout Standard After a proper configuration, the daemon reacts on received ICMPv6 multicast packets sent by a client to address ff02::1:2 \end_layout \begin_layout Subsection Configuration of the DHCPv6 server (dhcp6s) \end_layout \begin_layout Subsubsection Simple configuration \end_layout \begin_layout Standard dhcp6s's config file is normally /etc/dhcp6s.conf. An simple example looks like following: \end_layout \begin_layout Code interface eth0 { \end_layout \begin_layout Code server-preference 255; \end_layout \begin_layout Code renew-time 60; \end_layout \begin_layout Code rebind-time 90; \end_layout \begin_layout Code prefer-life-time 130; \end_layout \begin_layout Code valid-life-time 200; \end_layout \begin_layout Code allow rapid-commit; \end_layout \begin_layout Code option dns_servers 2001:db8:0:f101::1 sub.domain.example; \end_layout \begin_layout Code link AAA { \end_layout \begin_layout Code range 2001:db8:0:f101::1000 to 2001:db8:0:f101::ffff/64; \end_layout \begin_layout Code prefix 2001:db8:0:f101::/64; \end_layout \begin_layout Code }; \end_layout \begin_layout Code }; \end_layout \begin_layout Subsection Configuration of the DHCPv6 client (dhcp6c) \end_layout \begin_layout Subsubsection Simple configuration \end_layout \begin_layout Standard dhcp6c's config file is normally /etc/dhcp6c.conf. An simple example looks like following: \end_layout \begin_layout Code interface eth0 { \end_layout \begin_layout Code send rapid-commit; \end_layout \begin_layout Code request domain-name-servers; \end_layout \begin_layout Code }; \end_layout \begin_layout Subsection Usage \end_layout \begin_layout Subsubsection dhcpv6_server \end_layout \begin_layout Standard Start server, e.g. \end_layout \begin_layout Code # service dhcp6s start \end_layout \begin_layout Subsubsection dhcpv6_client \end_layout \begin_layout Standard Start client in foreground, e.g. \end_layout \begin_layout Code # dhcp6c -f eth0 \end_layout \begin_layout Subsection Debugging \end_layout \begin_layout Subsubsection dhcpv6_server \end_layout \begin_layout Standard The server has one foreground and two debug toggles (both should be used for debugging), here is an example: \end_layout \begin_layout Code # dhcp6s -d -D -f eth0 \end_layout \begin_layout Subsubsection dhcpv6_client \end_layout \begin_layout Standard As general debugging for test whether the IPv6 DHCP server is reable on the link use an IPv6 ping to the DHCP multicast address: \end_layout \begin_layout Code # ping6 -I eth0 ff02::1:2 \end_layout \begin_layout Standard The client has one foreground and two debug toggles, here is an example: \end_layout \begin_layout Code # dhcp6c -d -f eth0 \end_layout \begin_layout Code Oct/03/2005 17:18:16 dhcpv6 doesn't support hardware type 776 \end_layout \begin_layout Code Oct/03/2005 17:18:16 doesn't support sit0 address family 0 \end_layout \begin_layout Code Oct/03/2005 17:18:16 netlink_recv_rtgenmsg error \end_layout \begin_layout Code Oct/03/2005 17:18:16 netlink_recv_rtgenmsg error \end_layout \begin_layout Code Oct/03/2005 17:18:17 status code for this address is: success \end_layout \begin_layout Code Oct/03/2005 17:18:17 status code: success \end_layout \begin_layout Code Oct/03/2005 17:18:17 netlink_recv_rtgenmsg error \end_layout \begin_layout Code Oct/03/2005 17:18:17 netlink_recv_rtgenmsg error \end_layout \begin_layout Code Oct/03/2005 17:18:17 assigned address 2001:db8:0:f101::1002 prefix len is not \end_layout \begin_layout Code ¬ in any RAs prefix length using 64 bit instead \end_layout \begin_layout Code Oct/03/2005 17:18:17 renew time 60, rebind time 9 \end_layout \begin_layout Standard Note that the netlink error messages have no impact. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-isc-dhcp" \end_inset ISC Dynamic Host Configuration Server (dhcpd) \end_layout \begin_layout Standard ISC DHCP supports IPv6 since version 4.x. \end_layout \begin_layout Subsection Configuration of the ISC DHCP server for IPv6 (dhcpd) \end_layout \begin_layout Standard Note that currently, the ISC DHCP server can only serve IPv4 or IPv6, means you have to start the daemon twice (for IPv6 with option \begin_inset Quotes sld \end_inset -6 \begin_inset Quotes srd \end_inset ) to support both protocols. \end_layout \begin_layout Subsubsection Simple configuration \end_layout \begin_layout Standard Create a dedicated configuration file /etc/dhcp/dhcpd6.conf for the IPv6 part of the dhcpd. Note, that the router requires to have a interface configured with an IPv6 address out of the defined subnet. \end_layout \begin_layout Code default-lease-time 600; \end_layout \begin_layout Code max-lease-time 7200; \end_layout \begin_layout Code log-facility local7; \end_layout \begin_layout Code subnet6 2001:db8:0:1::/64 { \end_layout \begin_layout Code # Range for clients \end_layout \begin_layout Code range6 2001:db8:0:1::129 2001:db8:0:1::254; \end_layout \begin_layout Code \end_layout \begin_layout Code # Range for clients requesting a temporary address \end_layout \begin_layout Code range6 2001:db8:0:1::/64 temporary; \end_layout \begin_layout Code \end_layout \begin_layout Code # Additional options \end_layout \begin_layout Code option dhcp6.name-servers fec0:0:0:1::1; \end_layout \begin_layout Code option dhcp6.domain-search "domain.example"; \end_layout \begin_layout Code \end_layout \begin_layout Code # Prefix range for delegation to sub-routers \end_layout \begin_layout Code prefix6 2001:db8:0:100:: 2001:db8:0:f00:: /56; \end_layout \begin_layout Code \end_layout \begin_layout Code # Example for a fixed host address \end_layout \begin_layout Code host specialclient { \end_layout \begin_layout Code host-identifier option dhcp6.client-id 00:01:00:01:4a:1f:ba:e3:60:b9:1f:01: 23:45; \end_layout \begin_layout Code fixed-address6 2001:db8:0:1::127; \end_layout \begin_layout Code } \end_layout \begin_layout Code } \end_layout \begin_layout Standard Note that the \begin_inset Quotes sld \end_inset dhcp.client-id \begin_inset Quotes srd \end_inset no longer belongs to a MAC address, an unique ID is used instead! \begin_inset Quotes sld \end_inset dhcp6c \begin_inset Quotes srd \end_inset (see above) uses the file /var/lib/dhcpv6/dhcp6c_duid (would be created during first start, if not existing) as unique identity. It's a 14 byte long identifier, starting with a 2 byte length information (usually \begin_inset Quotes sld \end_inset 0x000e \begin_inset Quotes srd \end_inset ): \end_layout \begin_layout Code # hexdump -e '"%07.7_ax " 1/2 "%04x" " " 14/1 "%02x:" " \backslash n"' /var/lib/dhcpv6/dhcp6c_duid 0000000 000e 00:01:00:01:4a:1f:ba:e3:60:b9:1f:01 :23:45: \end_layout \begin_layout Subsection Usage \end_layout \begin_layout Subsubsection dhcpd \end_layout \begin_layout Standard Start server in foreground: \end_layout \begin_layout Code # /usr/sbin/dhcpd -6 -d -cf /etc/dhcp/dhcpd6.conf eth1 \end_layout \begin_layout Code Internet Systems Consortium DHCP Server 4.1.0 \end_layout \begin_layout Code Copyright 2004-2008 Internet Systems Consortium. \end_layout \begin_layout Code All rights reserved. \end_layout \begin_layout Code For info, please visit http://www.isc.org/sw/dhcp/ \end_layout \begin_layout Code Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file \end_layout \begin_layout Code Wrote 0 leases to leases file. \end_layout \begin_layout Code Bound to *:547 \end_layout \begin_layout Code Listening on Socket/5/eth1/2001:db8:0:1::/64 \end_layout \begin_layout Code Sending on Socket/5/eth1/2001:db8:0:1::/64 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-dibbler" \end_inset DHCP Server Dibbler \end_layout \begin_layout Standard Dibbler is also a DHCP server \end_layout \begin_layout Subsection Configuration of the Dibbler DHCP server for IPv6 \end_layout \begin_layout Subsubsection Simple configuration \end_layout \begin_layout Standard Create a dedicated configuration file /etc/dibbler/server.conf . Note, that the router requires to have a interface configured with an IPv6 address out of the defined subnet. \end_layout \begin_layout Code log-level 8 \end_layout \begin_layout Code log-mode short \end_layout \begin_layout Code preference 0 \end_layout \begin_layout Code iface "eth1" { \end_layout \begin_layout Code // also ranges can be defines, instead of exact values t1 1800-2000 t2 2700-3000 \end_layout \begin_layout Code prefered-lifetime 3600 \end_layout \begin_layout Code valid-lifetime 7200 \end_layout \begin_layout Code class { \end_layout \begin_layout Code pool 2001:6f8:12d8:1::/64 \end_layout \begin_layout Code } \end_layout \begin_layout Code option dns-server fec0:0:0:1::1 \end_layout \begin_layout Code option domain domain.example \end_layout \begin_layout Code } \end_layout \begin_layout Subsection Usage \end_layout \begin_layout Subsubsection dibbler-server \end_layout \begin_layout Standard Start server in foreground: \end_layout \begin_layout Code # dibbler-server run \end_layout \begin_layout Code | Dibbler - a portable DHCPv6, version 0.7.3 (SERVER, Linux port) \end_layout \begin_layout Code | Authors : Tomasz Mrugalski,Marek Senderski \end_layout \begin_layout Code | Licence : GNU GPL v2 only. Developed at Gdansk University of Technology. \end_layout \begin_layout Code | Homepage: http://klub.com.pl/dhcpv6/ \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Notice My pid (1789) is stored in /var/lib/dibbler/s erver.pid \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Notice Detected iface eth0/3, MAC=54:52:00:01:23:45. \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Notice Detected iface eth1/2, MAC=54:52:00:67:89:ab. \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Notice Detected iface lo/1, MAC=00:00:00:00:00:00. \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Debug Skipping database loading. \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Debug Cache:server-cache.xml file: parsing started, expecting 0 entries. \end_layout \begin_layout Code 2009.05.28 10:18:48 Server Notice Parsing /etc/dibbler/server.conf config file... \end_layout \begin_layout Code 18:48 Server Debug Setting 0 generic option(s). \end_layout \begin_layout Code 18:48 Server Debug 0 per-client configurations (exceptions) added. \end_layout \begin_layout Code 18:48 Server Debug Parsing /etc/dibbler/server.conf done. \end_layout \begin_layout Code 18:48 Server Info 0 client class(es) defined. \end_layout \begin_layout Code 18:48 Server Debug 1 interface(s) specified in /etc/dibbler/server.conf \end_layout \begin_layout Code 18:48 Server Info Mapping allow, deny list to class 0:0 allow/deny entries in total. \end_layout \begin_layout Code 18:48 Server Info Interface eth1/2 configuration has been loaded. \end_layout \begin_layout Code 18:48 Server Notice Running in stateful mode. \end_layout \begin_layout Code 18:48 Server Info My DUID is 00:01:00:01:11:aa:6d:a7:54:52:00:67:89:ab. \end_layout \begin_layout Code 18:48 Server Notice Creating multicast (ff02::1:2) socket on eth1/2 (eth1/2) interface. \end_layout \begin_layout Code 18:48 Server Debug Cache: size set to 1048576 bytes, 1 cache entry size is 87 bytes, so maximum 12052 address-client pair(s) may be cached. \end_layout \begin_layout Code 18:48 Server Notice Accepting connections. Next event in 4294967295 second(s). \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-tcpwrapper" \end_inset tcp_wrapper \end_layout \begin_layout Standard tcp_wrapper is a library which can help you to protect service against misuse. \end_layout \begin_layout Subsection Filtering capabilities \end_layout \begin_layout Standard You can use tcp_wrapper for \end_layout \begin_layout Itemize Filtering against source addresses (IPv4 or IPv6) \end_layout \begin_layout Itemize Filtering against users (requires a running ident daemon on the client) \end_layout \begin_layout Subsection Which program uses tcp_wrapper \end_layout \begin_layout Standard Following are known: \end_layout \begin_layout Itemize Each service which is called by xinetd (if xinetd is compiled using tcp_wrapper library) \end_layout \begin_layout Itemize sshd (if compiled using tcp_wrapper) \end_layout \begin_layout Subsection Usage \end_layout \begin_layout Standard tcp_wrapper is controlled by two files name /etc/hosts.allow and /etc/hosts.deny. For more information see \end_layout \begin_layout Code $ man hosts.allow \end_layout \begin_layout Subsubsection Example for /etc/hosts.allow \end_layout \begin_layout Standard In this file, each service which should be positive filtered (means connects are accepted) need a line. \end_layout \begin_layout Code sshd: 1.2.3. [2001:0db8:100:200::]/64 \end_layout \begin_layout Code daytime-stream: 1.2.3. [2001:0db8:100:200::]/64 \end_layout \begin_layout Standard Note: there are broken implementations around, which uses following broken IPv6 network description: [2001:0db8:100:200::/64]. Hopefully, such versions will be fixed soon. \end_layout \begin_layout Subsubsection Example for /etc/hosts.deny \end_layout \begin_layout Standard This file contains all negative filter entries and should normally deny the rest using \end_layout \begin_layout Code ALL: ALL \end_layout \begin_layout Standard If this node is a more sensible one you can replace the standard line above with this one, but this can cause a DoS attack (load of mailer and spool directory), if too many connects were made in short time. Perhaps a logwatch is better for such issues. \end_layout \begin_layout Code ALL: ALL: spawn (echo "Attempt from %h %a to %d at `date`" \end_layout \begin_layout Code | tee -a /var/log/tcp.deny.log | mail root@localhost) \end_layout \begin_layout Subsection Logging \end_layout \begin_layout Standard Depending on the entry in the syslog daemon configuration file /etc/syslog.conf the tcp_wrapper logs normally into /var/log/secure. \end_layout \begin_layout Subsubsection Refused connection \end_layout \begin_layout Standard A refused connection via IPv4 to an xinetd covered daytime service produces a line like following example \end_layout \begin_layout Code Jan 2 20:40:44 gate xinetd-ipv6[12346]: FAIL: daytime-stream libwrap \end_layout \begin_layout Code ¬ from=::ffff:1.2.3.4 \end_layout \begin_layout Code Jan 2 20:32:06 gate xinetd-ipv6[12346]: FAIL: daytime-stream libwrap \end_layout \begin_layout Code from=2001:0db8:100:200::212:34ff:fe12:3456 \end_layout \begin_layout Standard A refused connection via IPv4 to an dual-listen sshd produces a line like following example \end_layout \begin_layout Code Jan 2 20:24:17 gate sshd[12345]: refused connect from ::ffff:1.2.3.4 \end_layout \begin_layout Code ¬ (::ffff:1.2.3.4) \end_layout \begin_layout Code Jan 2 20:39:33 gate sshd[12345]: refused connect \end_layout \begin_layout Code from 2001:0db8:100:200::212:34ff:fe12:3456 \end_layout \begin_layout Code ¬ (2001:0db8:100:200::212:34ff:fe12:3456) \end_layout \begin_layout Subsubsection Permitted connection \end_layout \begin_layout Standard A permitted connection via IPv4 to an xinetd covered daytime service produces a line like following example \end_layout \begin_layout Code Jan 2 20:37:50 gate xinetd-ipv6[12346]: START: daytime-stream pid=0 \end_layout \begin_layout Code ¬ from=::ffff:1.2.3.4 \end_layout \begin_layout Code Jan 2 20:37:56 gate xinetd-ipv6[12346]: START: daytime-stream pid=0 \end_layout \begin_layout Code from=2001:0db8:100:200::212:34ff:fe12:3456 \end_layout \begin_layout Standard A permitted connection via IPv4 to an dual-listen sshd produces a line like following example \end_layout \begin_layout Code Jan 2 20:43:10 gate sshd[21975]: Accepted password for user from ::ffff:1.2.3.4 \end_layout \begin_layout Code ¬ port 33381 ssh2 \end_layout \begin_layout Code Jan 2 20:42:19 gate sshd[12345]: Accepted password for user \end_layout \begin_layout Code from 2001:0db8:100:200::212:34ff:fe12:3456 port 33380 ssh2 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-vsftpd" \end_inset vsftpd \end_layout \begin_layout Subsection Listening on IPv6 addresses \end_layout \begin_layout Standard Edit the configuration file, ususally /etc/vsftpd/vsftpd.conf, and adjust the listen option like \end_layout \begin_layout Code listen_ipv6=yes \end_layout \begin_layout Standard That's all. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-proftpd" \end_inset proftpd \end_layout \begin_layout Subsection Listening on IPv6 addresses \end_layout \begin_layout Standard Edit the configuration file, ususally /etc/proftpd.conf, but take care, not 100% logical in virtual host setup \end_layout \begin_layout Code \end_layout \begin_layout Code ... \end_layout \begin_layout Code Bind 2001:0DB8::1 \end_layout \begin_layout Code ... \end_layout \begin_layout Code \end_layout \begin_layout Standard That's all. \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "hints-daemons-others" \end_inset Other daemons \end_layout \begin_layout Standard Nowadays it's mostly simple, look for either a command line option or a configuration value to enable IPv6 listening. See manual page of the daemon or check related FAQs. It can happen that you can bind a daemon only to the IPv6- \begin_inset Quotes sld \end_inset any \begin_inset Quotes srd \end_inset -address (::) and not to bind to a dedicated IPv6 address, because the lack of support (depends on that what the programmer has implemented so far...). \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-programming" \end_inset Programming \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "chapter-section-using-API" \end_inset \begin_inset CommandInset label LatexCommand label name "chapter-programming-using-API" \end_inset Programming using C-API \end_layout \begin_layout Standard Related RFCs: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3493 / Basic Socket Interface Extensions for IPv6" target "http://www.faqs.org/rfcs/rfc3493.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3542 / Advanced Sockets Application Program Interface (API) for IPv6" target "http://www.faqs.org/rfcs/rfc3542.html" \end_inset \end_layout \begin_layout Standard Following contents of this section is contributed by John Wenker, Sr. Software Engineer Performance Technologies San Diego, CA USA \begin_inset CommandInset href LatexCommand href name "http://www.pt.com/" target "http://www.pt.com/" \end_inset . \end_layout \begin_layout Standard \begin_inset VSpace defskip \end_inset \end_layout \begin_layout Standard This section describes how to write IPv6 client-server applications under the Linux operating system. First thing's first, and credit must be given where it is due. The information contained in this section is derived from Chapters 2 through 4 of IPv6 Network Programming by Jun-ichiro itojun Hagino (ISBN 1-55558-318-0). The reader is encouraged to consult that book for more detailed information. It describes how to convert IPv4 applications to be IPv6 compatible in a protocol-independent way, and describes some of the common \bar under problems \bar default encountered during the conversion along with suggested solutions. At the time of this writing, this is the only book of which the author is aware that specifically addresses how to program IPv6 applications [since writing this section, the author has also become aware of the Porting applicati ons to IPv6 HowTo by Eva M. Castro at \begin_inset CommandInset href LatexCommand href name "http://jungla.dit.upm.es/~ecastro/IPv6-web/ipv6.html" target "http://jungla.dit.upm.es/~ecastro/IPv6-web/ipv6.html" \end_inset ]. Unfortunately, of the almost 360 pages in the book, maybe 60 are actually useful (the chapters mentioned). Nevertheless, without the guidance of that book, the author would have been unable to perform his job duties or compose this HowTo. While most (but certainly not all) of the information in the Hagino book is available via the Linux 'man' pages, application programmers will save a significant amount of time and frustration by reading the indicated chapters of the book rather than searching through the 'man' pages and online documentat ion. \end_layout \begin_layout Standard Other than the Hagino book, any other information presented in this HowTo was obtained through trial and error. Some items or explanations may not be entirely \begin_inset Quotes sld \end_inset correct \begin_inset Quotes srd \end_inset in the grand IPv6 scheme, but seem to work in practical application. \end_layout \begin_layout Standard The discussion that follows assumes the reader is already experienced with the traditional TCP/IP socket API. For more information on traditional socket programming, the Internetworking with TCP/IP series of textbooks by Comer & Stevens is hard to beat, specificall y Volume III: Client-Server Programming and Applications, Linux/POSIX Sockets Version (ISBN 0-13-032071-4). This HowTo also assumes that the reader has had at least a bare basic introduct ion to IPv6 and in particular the addressing scheme for network addresses (see Section 2.3). \end_layout \begin_layout Subsection Address Structures \end_layout \begin_layout Standard This section provides a brief overview of the structures provided in the socket API to represent network addresses (or more specifically transport endpoints) when using the Internet protocols in a client-server application. \end_layout \begin_layout Subsubsection IPv4 sockaddr_in \end_layout \begin_layout Standard In IPv4, network addresses are 32 bits long and define a network node. Addresses are written in dotted decimal notation, such as 192.0.2.1, where each number represents eight bits of the address. Such an IPv4 address is represented by the \family typewriter struct sockaddr_in \family default data type, which is defined in \family typewriter \family default . \end_layout \begin_layout Code struct sockaddr_in \end_layout \begin_layout Code { \end_layout \begin_layout Code sa_family_t sin_family; \end_layout \begin_layout Code in_port_t sin_port; \end_layout \begin_layout Code struct in_addr sin_addr; \end_layout \begin_layout Code /* Plus some padding for alignment */ \end_layout \begin_layout Code }; \end_layout \begin_layout Standard The \family typewriter sin_family \family default component indicates the address family. For IPv4 addresses, this is always set to \family typewriter AF_INET \family default . The \family typewriter sin_addr \family default field contains the 32-bit network address (in network byte order). Finally, the \family typewriter sin_port \family default component represents the transport layer port number (in network byte order). Readers should already be familiar with this structure, as this is the standard IPv4 address structure. \end_layout \begin_layout Subsubsection IPv6 sockaddr_in6 \end_layout \begin_layout Standard The biggest feature of IPv6 is its increased address space. Instead of 32-bit network addresses, IPv6 allots 128 bits to an address. Addresses are written in colon-hex notation of the form fe80::2c0:8cff:fe01:234 5, where each hex number separated by colons represents 16 bits of the address. Two consecutive colons indicate a string of consecutive zeros for brevity, and at most only one double-colon may appear in the address. IPv6 addresses are represented by the \family typewriter struct sockaddr_in6 \family default data type, also defined in \family typewriter \family default . \end_layout \begin_layout Code struct sockaddr_in6 \end_layout \begin_layout Code { \end_layout \begin_layout Code sa_family_t sin6_family; \end_layout \begin_layout Code in_port_t sin6_port; \end_layout \begin_layout Code uint32_t sin6_flowinfo; \end_layout \begin_layout Code struct in6_addr sin6_addr; \end_layout \begin_layout Code uint32_t sin6_scope_id; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard The \family typewriter sin6_family \family default , \family typewriter sin6_port \family default , and \family typewriter sin6_addr \family default components of the structure have the same meaning as the corresponding fields in the \family typewriter sockaddr_in \family default structure. However, the \family typewriter sin6_family \family default member is set to \family typewriter AF_INET6 \family default for IPv6 addresses, and the \family typewriter sin6_addr \family default field holds a 128-bit address instead of only 32 bits. \end_layout \begin_layout Standard The \family typewriter sin6_flowinfo \family default field is used for flow control, but is not yet standardized and can be ignored. \end_layout \begin_layout Standard The \family typewriter sin6_scope_id \family default field has an odd use, and it seems (at least to this naïve author) that the IPv6 designers took a huge step backwards when devising this. Apparently, 128-bit IPv6 network addresses are not unique. For example, it is possible to have two hosts, on separate networks, with the same link-local address (see Figure 1). In order to pass information to a specific host, more than just the network address is required; the scope identifier must also be specified. In Linux, the network interface name is used for the scope identifier (e.g. \begin_inset Quotes sld \end_inset eth0 \begin_inset Quotes srd \end_inset ) [be warned that the scope identifier is implementation dependent!]. Use the \family typewriter ifconfig(1M) \family default command to display a list of active network interfaces. \end_layout \begin_layout Standard A colon-hex network address can be augmented with the scope identifier to produce a "scoped address \begin_inset Quotes srd \end_inset . The percent sign ('%') is used to delimit the network address from the scope identifier. For example, \family typewriter fe80::1%eth0 \family default is a scoped IPv6 address where \family typewriter fe80::1 \family default represents the 128-bit network address and \family typewriter eth0 \family default is the network interface (i.e. the scope identifier). Thus, if a host resides on two networks, such as Host B in example below, the user now has to know which path to take in order to get to a particular host. In Figure 1, Host B addresses Host A using the scoped address \family typewriter fe80::1%eth0 \family default , while Host C is addressed with \family typewriter fe80::1%eth1 \family default . \end_layout \begin_layout Code Host A (fe80::1) ---- eth0 ---- Host B ---- eth1 ---- Host C (fe80::1) \end_layout \begin_layout Standard Getting back to the \family typewriter sockaddr_in6 \family default structure, its \family typewriter sin6_scope_id \family default field contains the index of the network interface on which a host may be found. Server applications will have this field set automatically by the socket API when they accept a connection or receive a datagram. For client applications, if a scoped address is passed as the node parameter to \family typewriter getaddrinfo(3) \family default (described later in this HowTo), then the \family typewriter sin6_scope_id \family default field will be filled in correctly by the system upon return from the function; if a scoped address is not supplied, then the sin6_scope_id field must be explicitly set by the client software prior to attempting to communicate with the remote server. The \family typewriter if_nametoindex(3) \family default function is used to translate a network interface name into its corresponding index. It is declared in \family typewriter \family default . \end_layout \begin_layout Subsubsection Generic Addresses \end_layout \begin_layout Standard As any programmer familiar with the traditional TCP/IP socket API knows, several socket functions deal with "generic" pointers. For example, a pointer to a generic \family typewriter struct sockaddr \family default data type is passed as a parameter to some socket functions (such as \family typewriter connect(2) \family default or \family typewriter bind(2) \family default ) rather than a pointer to a specific address type. Be careful\SpecialChar ldots the \family typewriter sockaddr_in6 \family default structure is larger than the generic \family typewriter sockaddr \family default structure! Thus, if your program \bar under receives \bar default a generic address whose actual type is unknown (e.g. it could be an IPv4 address structure or an IPv6 address structure), you must supply sufficient storage to hold the entire address. The \family typewriter struct sockaddr_storage \family default data type is defined in \family typewriter \family default for this purpose [do not #include this file directly within an application; use \family typewriter \family default as usual, and \family typewriter \family default will be implicitly included]. \end_layout \begin_layout Standard For example, consider the \family typewriter recvfrom(2) \family default system call, which is used to receive a message from a remote peer. Its function prototype is: \end_layout \begin_layout Code ssize_t recvfrom( int s, \end_layout \begin_layout Code void *buf, \end_layout \begin_layout Code size_t len, \end_layout \begin_layout Code int flags, \end_layout \begin_layout Code struct sockaddr *from, \end_layout \begin_layout Code socklen_t *fromlen ); \end_layout \begin_layout Standard The from parameter points to a generic \family typewriter sockaddr \family default structure. If data can be received from an IPv6 peer on the socket referenced by \family typewriter s \family default , then \family typewriter from \family default should point to a data type of \family typewriter struct sockaddr_storage \family default , as in the following dummy example: \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Read a message from a remote peer, and return a buffer pointer to \end_layout \begin_layout Code ** the caller. \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** 's' is the file descriptor for the socket. \end_layout \begin_layout Code */ \end_layout \begin_layout Code char *rcvMsg( int s ) \end_layout \begin_layout Code { \end_layout \begin_layout Code static char bfr[ 1025 ]; /* Where the msg is stored. */ \end_layout \begin_layout Code ssize_t count; \end_layout \begin_layout Code struct sockaddr_storage ss; /* Where the peer adr goes. */ \end_layout \begin_layout Code socklen_t sslen; \end_layout \begin_layout Code sslen = sizeof( ss ); \end_layout \begin_layout Code count = recvfrom( s, \end_layout \begin_layout Code bfr, \end_layout \begin_layout Code sizeof( bfr ) - 1, \end_layout \begin_layout Code 0, \end_layout \begin_layout Code (struct sockaddr*) &ss, \end_layout \begin_layout Code &sslen ); \end_layout \begin_layout Code bfr[ count ] = ' \backslash 0'; /* Null-terminates the message. */ \end_layout \begin_layout Code return bfr; \end_layout \begin_layout Code } /* End rcvMsg() */ \end_layout \begin_layout Standard As seen in the above example, \family typewriter ss \family default (a \family typewriter struct sockaddr_storage \family default data object) is used to receive the peer address information, but it's address is typecast to a generic \family typewriter struct sockaddr* \family default pointer in the call to \family typewriter recvfrom(2) \family default . \end_layout \begin_layout Subsection Lookup Functions \end_layout \begin_layout Standard Traditionally, hostname and service name resolution were performed by functions such as \family typewriter gethostbyname(3) \family default and \family typewriter getservbyname(3) \family default . These traditional lookup functions are still available, but they are not forward compatible to IPv6. Instead, the IPv6 socket API provides new lookup functions that consolidate the functionality of several traditional functions. These new lookup functions are also backward compatible with IPv4, so a programmer can use the same translation algorithm in an application for both the IPv4 and IPv6 protocols. This is an important feature, because obviously a global IPv6 infrastructure isn't going to be put in place overnight. Thus, during the transition period from IPv4 to IPv6, client-server application s should be designed with the flexibility to handle both protocols simultaneousl y. The example programs at the end of this chapter do just that. \end_layout \begin_layout Standard The primary lookup function in the new socket API is \family typewriter getaddrinfo(3) \family default . Its prototype is as follows. \end_layout \begin_layout Code int getaddrinfo( const char *node, \end_layout \begin_layout Code const char *service, \end_layout \begin_layout Code const struct addrinfo *hints, \end_layout \begin_layout Code struct addrinfo **res ); \end_layout \begin_layout Standard The node parameter is a pointer to the hostname or IP address being translated. The referenced string can be a hostname, IPv4 dotted decimal address, or IPv6 colon-hex address (possibly scoped). The \family typewriter service \family default parameter is a pointer to the transport layer's service name or port number. It can be specified as a name found in \family typewriter /etc/services \family default or a decimal number. \family typewriter getaddrinfo(3) \family default resolves the host/service combination and returns a \bar under list \bar default of address records; a pointer to the list is placed in the location pointed at by \family typewriter res \family default . For example, suppose a host can be identified by both an IPv4 and IPv6 address, and that the indicated service has both a TCP entry and UDP entry in \family typewriter /etc/services \family default . In such a scenario, it is not inconceivable that four address records are returned; one for TCP/IPv6, one for UDP/IPv6, one for TCP/IPv4, and one for UDP/IPv4. \end_layout \begin_layout Standard The definition for \family typewriter struct addrinfo \family default is found in \family typewriter \family default (as is the declaration for getaddrinfo(3) and the other functions described in this section). The structure has the following format: \end_layout \begin_layout Code struct addrinfo \end_layout \begin_layout Code { \end_layout \begin_layout Code int ai_flags; \end_layout \begin_layout Code int ai_family; \end_layout \begin_layout Code int ai_socktype; \end_layout \begin_layout Code int ai_protocol; \end_layout \begin_layout Code socklen_t ai_addrlen; \end_layout \begin_layout Code struct sockaddr *ai_addr; \end_layout \begin_layout Code char *ai_canonname; \end_layout \begin_layout Code struct addrinfo *ai_next; \end_layout \begin_layout Code }; \end_layout \begin_layout Standard Consult the 'man' page for \family typewriter getaddrinfo(3) \family default for detailed information about the various fields; this HowTo only describes a subset of them, and only to the extent necessary for normal IPv6 programming. \end_layout \begin_layout Standard The \family typewriter ai_family \family default , \family typewriter ai_socktype \family default , and \family typewriter ai_protocol \family default fields have the exact same meaning as the parameters to the \family typewriter socket(2) \family default system call. The \family typewriter ai_family \family default field indicates the \bar under protocol \bar default family (not the address family) associated with the record, and will be \family typewriter PF_INET6 \family default for IPv6 or \family typewriter PF_INET \family default for IPv4. The \family typewriter ai_socktype \family default parameter indicates the type of socket to which the record corresponds; \family typewriter SOCK_STREAM \family default for a reliable connection-oriented byte-stream or \family typewriter SOCK_DGRAM \family default for connectionless communication. The \family typewriter ai_protocol \family default field specifies the underlying transport protocol for the record. \end_layout \begin_layout Standard The \family typewriter ai_addr \family default field points to a generic \family typewriter struct sockaddr \family default object. Depending on the value in the \family typewriter ai_family \family default field, it will point to either a \family typewriter struct sockaddr_in \family default ( \family typewriter PF_INET \family default ) or a \family typewriter struct sockaddr_in6 \family default ( \family typewriter PF_INET6 \family default ). The \family typewriter ai_addrlen \family default field contains the size of the object pointed at by the \family typewriter ai_addr \family default field. \end_layout \begin_layout Standard As mentioned, \family typewriter getaddrinfo(3) \family default returns a list of address records. The \family typewriter ai_next \family default field points to the next record in the list. \end_layout \begin_layout Standard The \family typewriter hints \family default parameter to \family typewriter getaddrinfo(3) \family default is also of type \family typewriter struct addrinfo \family default and acts as a filter for the address records returned in \family typewriter res \family default . If \family typewriter hints \family default is \family typewriter NULL \family default , all matching records are returned; but if \family typewriter hints \family default is non- \family typewriter NULL \family default , the referenced structure gives "hints" to \family typewriter getaddrinfo(3) \family default about which records to return. Only the \family typewriter ai_flags \family default , \family typewriter ai_family \family default , \family typewriter ai_socktype \family default , and \family typewriter ai_protocol \family default fields are significant in the \family typewriter hints \family default structure, and all other fields should be set to zero. \end_layout \begin_layout Standard Programs can use \family typewriter hints->ai_family \family default to specify the protocol family. For example, if it is set to \family typewriter PF_INET6 \family default , then only IPv6 address records are returned. Likewise, setting \family typewriter hints->ai_family \family default to \family typewriter PF_INET \family default results in only IPv4 address records being returned. If an application wants both IPv4 and IPv6 records, the field should be set to \family typewriter PF_UNSPEC \family default . \end_layout \begin_layout Standard The \family typewriter hints->socktype \family default field can be set to \family typewriter SOCK_STREAM \family default to return only records that correspond to connection-oriented byte streams, \family typewriter SOCK_DGRAM \family default to return only records corresponding to connectionless communication, or \family typewriter 0 \family default to return both. \end_layout \begin_layout Standard For the Internet protocols, there is only one protocol associated with connectio n-oriented sockets (TCP) and one protocol associated with connectionless sockets (UDP), so setting \family typewriter hints->ai_socktype \family default to \family typewriter SOCK_STREAM \family default or \family typewriter SOCK_DGRAM \family default is the same as saying, "Give me only TCP records," or "Give me only UDP records," respectively. With that in mind, the \family typewriter hints->ai_protocol \family default field isn't really that important with the Internet protocols, and pretty much mirrors the \family typewriter hints->ai_socktype \family default field. Nevertheless, \family typewriter hints->ai_protocol \family default can be set to \family typewriter IPPROTO_TCP \family default to return only TCP records, \family typewriter IPPROTO_UDP \family default to return only UDP records, or \family typewriter 0 \family default for both. \end_layout \begin_layout Standard The \family typewriter node \family default or \family typewriter service \family default parameter to \family typewriter gethostbyname(3) \family default can be \family typewriter NULL \family default , but not both. If \family typewriter node \family default is \family typewriter NULL \family default , then the \family typewriter ai_flags field \family default of the \family typewriter hints \family default parameter specifies how the network address in a returned record is set (i.e. the \family typewriter sin_addr \family default or \family typewriter sin6_addr \family default field of the object pointed at by the \family typewriter ai_addr \family default component in a returned record). If the \family typewriter AI_PASSIVE \family default flag is set in \family typewriter hints \family default , then the returned network addresses are left unresolved (all zeros). This is how server applications would use \family typewriter getaddrinfo(3) \family default . If the flag is not set, then the address is set to the local loopback address (::1 for IPv6 or 127.0.0.1 for IPv4). This is one way a client application can specify that the target server is running on the same machine as the client. If the \family typewriter service \family default parameter is \family typewriter NULL \family default , the port number in the returned address records remains unresolved. \end_layout \begin_layout Standard The \family typewriter getaddrinfo(3) \family default function returns zero on success, or an error code. In the case of an error, the \family typewriter gai_strerror(3) \family default function is used to obtain a character pointer to an error message correspondin g to the error code, just like \family typewriter strerror(3) \family default does in the standard 'C' library. \end_layout \begin_layout Standard Once the address list is no longer needed, it must be freed by the application. This is done with the \family typewriter freeaddrinfo(3) \family default function. \end_layout \begin_layout Standard The last function that will be mentioned in this section is \family typewriter getnameinfo(3) \family default . This function is the inverse of \family typewriter getaddrinfo(3) \family default ; it is used to create a string representation of the hostname and service from a generic \family typewriter struct sockaddr \family default data object. It has the following prototype. \end_layout \begin_layout Code int getnameinfo( const struct sockaddr *sa, \end_layout \begin_layout Code socklen_t salen, \end_layout \begin_layout Code char *host, \end_layout \begin_layout Code size_t hostlen, \end_layout \begin_layout Code char *serv, \end_layout \begin_layout Code size_t servlen, \end_layout \begin_layout Code int flags ); \end_layout \begin_layout Standard The \family typewriter sa \family default parameter points to the address structure in question, and \family typewriter salen \family default contains its size. The \family typewriter host \family default parameter points to a buffer where the null-terminated hostname string is placed, and the hostlen parameter is the size of that buffer. If there is no hostname that corresponds to the address, then the network address (dotted decimal or colon-hex) is placed in \family typewriter host \family default . Likewise, the \family typewriter serv \family default parameter points to a buffer where the null-terminated service name string (or port number) is placed, and the \family typewriter servlen \family default parameter is the size of that buffer. The \family typewriter flags \family default parameter modifies the function's behavior; in particular, the \family typewriter NI_NUMERICHOST \family default flag indicates that the converted hostname should always be formatted in numeric form (i.e. dotted decimal or colon-hex), and the \family typewriter NI_NUMERICSERV \family default flag indicates that the converted service should always be in numeric form (i.e. the port number). \end_layout \begin_layout Standard The symbols \family typewriter NI_MAXHOST \family default and \family typewriter NI_MAXSERV \family default are available to applications and represent the maximum size of any converted hostname or service name, respectively. Use these when declaring output buffers for \family typewriter getnameinfo(3) \family default . \end_layout \begin_layout Subsection Quirks Encountered \end_layout \begin_layout Standard Before jumping into the programming examples, there are several quirks in IPv6 of which the reader should be aware. The more significant ones (in addition to the non-uniqueness of IPv6 network addresses already discussed) are described in the paragraphs below. \end_layout \begin_layout Subsubsection IPv4 Mapped Addresses \end_layout \begin_layout Standard For security reasons that this author won't pretend to understand, "IPv4 mapped addresses" should not be allowed in IPv6-capable server applications. To put it in terms that everyone can understand, this simply means that a server should not accept IPv4 traffic on an IPv6 socket (an otherwise legal operation). An IPv4 mapped address is a mixed-format address of the form: \end_layout \begin_layout Code ::ffff:192.0.2.1 \end_layout \begin_layout Standard where the first portion is in IPv6 colon-hex format and the last portion is in IPv4 dotted decimal notation. The dotted decimal IPv4 address is the actual network address, but it is being mapped into an IPv6 compatible format. \end_layout \begin_layout Standard To prevent IPv4 mapped addresses from being accepted on an IPv6 socket, server applications must explicitly set the \family typewriter IPV6_V6ONLY \family default socket option on all IPv6 sockets created [the Hagino book implies that this is only a concern with server applications. However, it has been observed during testing that if a client application uses an IPv4 mapped address to specify the target server, and the target server has IPv4 mapped addresses disabled, the connection still completes regardless. On the server side, the connection endpoint is an IPv4 socket as desired; but on the client side, the connection endpoint is an IPv6 socket. Setting the IPV6_V6ONLY socket option on the client side as well as the server side prevents any connection from being established at all.]. There's only one problem. Apparently, \family typewriter IPV6_V6ONLY \family default isn't defined on all systems [or at least it wasn't in 2005 when the Hagino book was written]. The server example at the end of this chapter provides a method for handling this problem. \end_layout \begin_layout Standard If IPv4 traffic cannot be handled on IPv6 sockets, then that implies that server applications must open both an IPv4 and IPv6 socket for a particular network service if it wants to handle requests from either protocol. This goes back to the flexibility issue mentioned earlier. If \family typewriter getaddrinfo(3) \family default returns multiple address records, then server applications should traverse the list and open a passive socket for each address provided. \end_layout \begin_layout Subsubsection Cannot Specify the Scope Identifier in /etc/hosts \end_layout \begin_layout Standard It is possible to assign a hostname to an IPv6 network address in \family typewriter /etc/hosts \family default . For example, the following is an excerpt from the \family typewriter /etc/hosts \family default file on the author's development system. \end_layout \begin_layout Code ::1 localhost \end_layout \begin_layout Code 127.0.0.1 localhost \end_layout \begin_layout Code fe80::2c0:8cff:fe01:2345 pt141 \end_layout \begin_layout Code 192.0.2.1 pt141 \end_layout \begin_layout Standard The "localhost" and "pt141" hostnames can be translated to either an IPv4 or IPv6 network address. So, for example, if "pt141" is passed as the node parameter to \family typewriter getaddrinfo(3) \family default , the function returns both an IPv4 and IPv6 address record for the host (assuming the behavior hasn't been modified by the hints parameter). Unfortunately, a scoped address cannot be used in \family typewriter /etc/hosts \family default . Doing so results in \family typewriter getaddrinfo(3) \family default returning only the IPv4 record. \end_layout \begin_layout Subsubsection Client & Server Residing on the Same Machine \end_layout \begin_layout Standard Suppose a machine has the IPv4 address 192.0.2.1. A client application running on that machine can connect to a server applicatio n on the same machine by using either the local loopback address (127.0.0.1) or the network address (192.0.2.1) as the target server. Much to this author's surprise (and dismay), it turns out that an IPv6 client application cannot connect to a server application on the same machine if it uses the network address of that machine as the target; it must use the local loopback address (::1). \end_layout \begin_layout Subsection Putting It All Together (A Client-Server Programming Example) \end_layout \begin_layout Standard Now it's time to put everything discussed thus far together into a sample client-server application. The remainder of this section is devoted to a remote time-of-day application (the 'daytime' Internet service) [I noticed that Ms. Castro used a 'daytime' example in her \emph on Porting applications to IPv6 HowTo \emph default . For the record, the source code presented here is original, developed from scratch, and any similarity between it and any other publicly available 'daytime' example is purely coincidental.]. The source code presented in this section was developed and tested on a RedHat Linux release using the 2.6 kernel (2.6.9 to be specific). Readers may use the source code freely, so long as proper credit is attributed; but of course the standard disclaimer must be given first: \end_layout \begin_layout Quotation Although the sample source code is believed to be free of errors, the author makes no guarantees as to its reliability, especially considering that some error paths were intentionally omitted for brevity. Use it at your own risk! \end_layout \begin_layout Standard When you get right down to it, there really aren't that many differences between IPv4 and IPv6 applications. The trick is to code IPv6 applications in a protocol-independent manner, such that they can handle both IPv4 and IPv6 simultaneously and transparently. This sample application does just that. The only protocol-dependent code in the example occurs when printing network addresses in verbose mode; but only \bar under after \bar default the \family typewriter ai_family field \family default in the \family typewriter addrinfo \family default structure has been checked, so the programs know exactly what type of address they're handling at the time. \end_layout \begin_layout Subsubsection 'Daytime' Server Code \end_layout \begin_layout Standard The server code is found in file tod6d.c (time-of-day IPv6 daemon). Once built, the server may be started using the following command syntax (assuming tod6d is the executable file): \end_layout \begin_layout Code tod6d [-v] [service] \end_layout \begin_layout Standard ARGUMENTS: \end_layout \begin_layout Description service The service (or well-known port) on which to listen. Default is "daytime". \end_layout \begin_layout Standard OPTIONS: \end_layout \begin_layout Description -v Turn on verbose mode. \end_layout \begin_layout Standard The server handles both TCP and UDP requests on the network. The server source code contained in tod6d.c follows: \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * File: tod6d.c \end_layout \begin_layout Code * Description: Contains source code for an IPv6-capable 'daytime' server. \end_layout \begin_layout Code * Author: John Wenker, Sr. Software Engineer, \end_layout \begin_layout Code * Performance Technologies, San Diego, USA \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** System header files. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #include /* errno declaration & error codes. */ \end_layout \begin_layout Code #include /* getaddrinfo(3) et al. */ \end_layout \begin_layout Code #include /* sockaddr_in & sockaddr_in6 definition. */ \end_layout \begin_layout Code #include /* printf(3) et al. */ \end_layout \begin_layout Code #include /* exit(2). */ \end_layout \begin_layout Code #include /* String manipulation & memory functions. */ \end_layout \begin_layout Code #include /* poll(2) and related definitions. */ \end_layout \begin_layout Code #include /* Socket functions (socket(2), bind(2), etc). */ \end_layout \begin_layout Code #include /* time(2) & ctime(3). */ \end_layout \begin_layout Code #include /* getopt(3), read(2), etc. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Constants. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define DFLT_SERVICE "daytime" /* Default service name. */ \end_layout \begin_layout Code #define INVALID_DESC -1 /* Invalid file descriptor. */ \end_layout \begin_layout Code #define MAXCONNQLEN 3 /* Max nbr of connection requests to queue. */ \end_layout \begin_layout Code #define MAXTCPSCKTS 2 /* One TCP socket for IPv4 & one for IPv6. */ \end_layout \begin_layout Code #define MAXUDPSCKTS 2 /* One UDP socket for IPv4 & one for IPv6. */ \end_layout \begin_layout Code #define VALIDOPTS "v" /* Valid command options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Simple boolean type definition. \end_layout \begin_layout Code */ \end_layout \begin_layout Code typedef enum { false = 0, true } boolean; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Prototypes for internal helper functions. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static int openSckt( const char *service, \end_layout \begin_layout Code const char *protocol, \end_layout \begin_layout Code int desc[ ], \end_layout \begin_layout Code size_t *descSize ); \end_layout \begin_layout Code static void tod( int tSckt[ ], \end_layout \begin_layout Code size_t tScktSize, \end_layout \begin_layout Code int uSckt[ ], \end_layout \begin_layout Code size_t uScktSize ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Global (within this file only) data objects. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static char hostBfr[ NI_MAXHOST ]; /* For use w/getnameinfo(3). */ \end_layout \begin_layout Code static const char *pgmName; /* Program name w/o dir prefix. */ \end_layout \begin_layout Code static char servBfr[ NI_MAXSERV ]; /* For use w/getnameinfo(3). */ \end_layout \begin_layout Code static boolean verbose = false; /* Verbose mode indication. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Usage macro for command syntax violations. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define USAGE \backslash \end_layout \begin_layout Code { \backslash \end_layout \begin_layout Code fprintf( stderr, \backslash \end_layout \begin_layout Code "Usage: %s [-v] [service] \backslash n", \backslash \end_layout \begin_layout Code pgmName ); \backslash \end_layout \begin_layout Code exit( 127 ); \backslash \end_layout \begin_layout Code } /* End USAGE macro. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Macro to terminate the program if a system call error occurs. The system \end_layout \begin_layout Code ** call must be one of the usual type that returns -1 on error. This macro is \end_layout \begin_layout Code ** a modified version of a macro authored by Dr. V. Vinge, SDSU Dept. of \end_layout \begin_layout Code ** Computer Science (retired)... best professor I ever had. I hear he writes \end_layout \begin_layout Code ** great science fiction in addition to robust code, too. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define CHK(expr) \backslash \end_layout \begin_layout Code do \backslash \end_layout \begin_layout Code { \backslash \end_layout \begin_layout Code if ( (expr) == -1 ) \backslash \end_layout \begin_layout Code { \backslash \end_layout \begin_layout Code fprintf( stderr, \backslash \end_layout \begin_layout Code "%s (line %d): System call ERROR - %s. \backslash n", \backslash \end_layout \begin_layout Code pgmName, \backslash \end_layout \begin_layout Code __LINE__, \backslash \end_layout \begin_layout Code strerror( errno ) ); \backslash \end_layout \begin_layout Code exit( 1 ); \backslash \end_layout \begin_layout Code } /* End IF system call failed. */ \backslash \end_layout \begin_layout Code } while ( false ) \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: main \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Set up a time-of-day server and handle network requests. This server \end_layout \begin_layout Code * handles both TCP and UDP requests. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * The usual argc and argv parameters to a main() function. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * This is a daemon program and never returns. However, in the degenerate \end_layout \begin_layout Code * case where no sockets are created, the function returns zero. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code int main( int argc, \end_layout \begin_layout Code char *argv[ ] ) \end_layout \begin_layout Code { \end_layout \begin_layout Code int opt; \end_layout \begin_layout Code const char *service = DFLT_SERVICE; \end_layout \begin_layout Code int tSckt[ MAXTCPSCKTS ]; /* Array of TCP socket descriptors. */ \end_layout \begin_layout Code size_t tScktSize = MAXTCPSCKTS; /* Size of uSckt (# of elements). */ \end_layout \begin_layout Code int uSckt[ MAXUDPSCKTS ]; /* Array of UDP socket descriptors. */ \end_layout \begin_layout Code size_t uScktSize = MAXUDPSCKTS; /* Size of uSckt (# of elements). */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Set the program name (w/o directory prefix). \end_layout \begin_layout Code */ \end_layout \begin_layout Code pgmName = strrchr( argv[ 0 ], '/' ); \end_layout \begin_layout Code pgmName = pgmName == NULL ? argv[ 0 ] : pgmName + 1; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command options. \end_layout \begin_layout Code */ \end_layout \begin_layout Code opterr = 0; /* Turns off "invalid option" error messages. */ \end_layout \begin_layout Code while ( ( opt = getopt( argc, argv, VALIDOPTS ) ) >= 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code switch ( opt ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 'v': /* Verbose mode. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code verbose = true; \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code default: \end_layout \begin_layout Code { \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on command option. */ \end_layout \begin_layout Code } /* End WHILE processing options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command line arguments. \end_layout \begin_layout Code */ \end_layout \begin_layout Code switch ( argc - optind ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 0: break; \end_layout \begin_layout Code case 1: service = argv[ optind ]; break; \end_layout \begin_layout Code default: USAGE; \end_layout \begin_layout Code } /* End SWITCH on number of command line arguments. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Open both a TCP and UDP socket, for both IPv4 & IPv6, on which to receive \end_layout \begin_layout Code ** service requests. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( openSckt( service, "tcp", tSckt, &tScktSize ) < 0 ) || \end_layout \begin_layout Code ( openSckt( service, "udp", uSckt, &uScktSize ) < 0 ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code exit( 1 ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Run the time-of-day server. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( tScktSize > 0 ) || ( uScktSize > 0 ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code tod( tSckt, /* tod() never returns. */ \end_layout \begin_layout Code tScktSize, \end_layout \begin_layout Code uSckt, \end_layout \begin_layout Code uScktSize ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Since tod() never returns, execution only gets here if no sockets were \end_layout \begin_layout Code ** created. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: No sockets opened... terminating. \backslash n", \end_layout \begin_layout Code pgmName ); \end_layout \begin_layout Code } \end_layout \begin_layout Code return 0; \end_layout \begin_layout Code } /* End main() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: openSckt \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Open passive (server) sockets for the indicated inet service & protocol. \end_layout \begin_layout Code * Notice in the last sentence that "sockets" is plural. During the interim \end_layout \begin_layout Code * transition period while everyone is switching over to IPv6, the server \end_layout \begin_layout Code * application has to open two sockets on which to listen for connections... \end_layout \begin_layout Code * one for IPv4 traffic and one for IPv6 traffic. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * service - Pointer to a character string representing the well-known port \end_layout \begin_layout Code * on which to listen (can be a service name or a decimal number). \end_layout \begin_layout Code * protocol - Pointer to a character string representing the transport layer \end_layout \begin_layout Code * protocol (only "tcp" or "udp" are valid). \end_layout \begin_layout Code * desc - Pointer to an array into which the socket descriptors are \end_layout \begin_layout Code * placed when opened. \end_layout \begin_layout Code * descSize - This is a value-result parameter. On input, it contains the \end_layout \begin_layout Code * max number of descriptors that can be put into 'desc' (i.e. the \end_layout \begin_layout Code * number of elements in the array). Upon return, it will contain \end_layout \begin_layout Code * the number of descriptors actually opened. Any unused slots in \end_layout \begin_layout Code * 'desc' are set to INVALID_DESC. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * 0 on success, -1 on error. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static int openSckt( const char *service, \end_layout \begin_layout Code const char *protocol, \end_layout \begin_layout Code int desc[ ], \end_layout \begin_layout Code size_t *descSize ) \end_layout \begin_layout Code { \end_layout \begin_layout Code struct addrinfo *ai; \end_layout \begin_layout Code int aiErr; \end_layout \begin_layout Code struct addrinfo *aiHead; \end_layout \begin_layout Code struct addrinfo hints = { .ai_flags = AI_PASSIVE, /* Server mode. \end_layout \begin_layout Code ¬ */ \end_layout \begin_layout Code .ai_family = PF_UNSPEC }; /* IPv4 or IPv6. \end_layout \begin_layout Code ¬ */ \end_layout \begin_layout Code size_t maxDescs = *descSize; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Initialize output parameters. When the loop completes, *descSize is 0. \end_layout \begin_layout Code */ \end_layout \begin_layout Code while ( *descSize > 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code desc[ --( *descSize ) ] = INVALID_DESC; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Check which protocol is selected (only TCP and UDP are valid). \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( strcmp( protocol, "tcp" ) == 0 ) /* TCP protocol. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code hints.ai_socktype = SOCK_STREAM; \end_layout \begin_layout Code hints.ai_protocol = IPPROTO_TCP; \end_layout \begin_layout Code } \end_layout \begin_layout Code else if ( strcmp( protocol, "udp" ) == 0 ) /* UDP protocol. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code hints.ai_socktype = SOCK_DGRAM; \end_layout \begin_layout Code hints.ai_protocol = IPPROTO_UDP; \end_layout \begin_layout Code } \end_layout \begin_layout Code else /* Invalid protocol. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown transport " \end_layout \begin_layout Code "layer protocol \backslash "%s \backslash ". \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code protocol ); \end_layout \begin_layout Code return -1; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Look up the service's well-known port number. Notice that NULL is being \end_layout \begin_layout Code ** passed for the 'node' parameter, and that the AI_PASSIVE flag is set in \end_layout \begin_layout Code ** 'hints'. Thus, the program is requesting passive address information. \end_layout \begin_layout Code ** The network address is initialized to :: (all zeros) for IPv6 records, or \end_layout \begin_layout Code ** 0.0.0.0 for IPv4 records. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( aiErr = getaddrinfo( NULL, \end_layout \begin_layout Code service, \end_layout \begin_layout Code &hints, \end_layout \begin_layout Code &aiHead ) ) != 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code gai_strerror( aiErr ) ); \end_layout \begin_layout Code return -1; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** For each of the address records returned, attempt to set up a passive \end_layout \begin_layout Code ** socket. \end_layout \begin_layout Code */ \end_layout \begin_layout Code for ( ai = aiHead; \end_layout \begin_layout Code ( ai != NULL ) && ( *descSize < maxDescs ); \end_layout \begin_layout Code ai = ai->ai_next ) \end_layout \begin_layout Code { \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the current address info. Start with the protocol- \end_layout \begin_layout Code ** independent fields first. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "Setting up a passive socket based on the " \end_layout \begin_layout Code "following address info: \backslash n" \end_layout \begin_layout Code " ai_flags = 0x%02X \backslash n" \end_layout \begin_layout Code " ai_family = %d (PF_INET = %d, PF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " ai_socktype = %d (SOCK_STREAM = %d, SOCK_DGRAM = %d) \backslash n" \end_layout \begin_layout Code " ai_protocol = %d (IPPROTO_TCP = %d, IPPROTO_UDP = %d) \backslash n" \end_layout \begin_layout Code " ai_addrlen = %d (sockaddr_in = %d, " \end_layout \begin_layout Code "sockaddr_in6 = %d) \backslash n", \end_layout \begin_layout Code ai->ai_flags, \end_layout \begin_layout Code ai->ai_family, \end_layout \begin_layout Code PF_INET, \end_layout \begin_layout Code PF_INET6, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code SOCK_STREAM, \end_layout \begin_layout Code SOCK_DGRAM, \end_layout \begin_layout Code ai->ai_protocol, \end_layout \begin_layout Code IPPROTO_TCP, \end_layout \begin_layout Code IPPROTO_UDP, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code sizeof( struct sockaddr_in ), \end_layout \begin_layout Code sizeof( struct sockaddr_in6 ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Now display the protocol-specific formatted socket address. Note \end_layout \begin_layout Code ** that the program is requesting that getnameinfo(3) convert the \end_layout \begin_layout Code ** host & service into numeric strings. \end_layout \begin_layout Code */ \end_layout \begin_layout Code getnameinfo( ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code sizeof( hostBfr ), \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code sizeof( servBfr ), \end_layout \begin_layout Code NI_NUMERICHOST | NI_NUMERICSERV ); \end_layout \begin_layout Code switch ( ai->ai_family ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case PF_INET: /* IPv4 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in *p = (struct sockaddr_in*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin_addr: %s \backslash n" \end_layout \begin_layout Code " sin_port: %s \backslash n", \end_layout \begin_layout Code p->sin_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv4. */ \end_layout \begin_layout Code case PF_INET6: /* IPv6 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in6 *p = (struct sockaddr_in6*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin6_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin6_addr: %s \backslash n" \end_layout \begin_layout Code " sin6_port: %s \backslash n" \end_layout \begin_layout Code " sin6_flowinfo: %d \backslash n" \end_layout \begin_layout Code " sin6_scope_id: %d \backslash n", \end_layout \begin_layout Code p->sin6_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code p->sin6_flowinfo, \end_layout \begin_layout Code p->sin6_scope_id ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv6. */ \end_layout \begin_layout Code default: /* Can never get here, but just for completeness. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown protocol family (%d). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code ai->ai_family ); \end_layout \begin_layout Code freeaddrinfo( aiHead ); \end_layout \begin_layout Code return -1; \end_layout \begin_layout Code } /* End DEFAULT case (unknown protocol family). */ \end_layout \begin_layout Code } /* End SWITCH on protocol family. */ \end_layout \begin_layout Code } /* End IF verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Create a socket using the info in the addrinfo structure. \end_layout \begin_layout Code */ \end_layout \begin_layout Code CHK( desc[ *descSize ] = socket( ai->ai_family, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code ai->ai_protocol ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Here is the code that prevents "IPv4 mapped addresses", as discussed \end_layout \begin_layout Code ** in Section 22.1.3.1. If an IPv6 socket was just created, then set the \end_layout \begin_layout Code ** IPV6_V6ONLY socket option. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ai->ai_family == PF_INET6 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code #if defined( IPV6_V6ONLY ) \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Disable IPv4 mapped addresses. \end_layout \begin_layout Code */ \end_layout \begin_layout Code int v6Only = 1; \end_layout \begin_layout Code CHK( setsockopt( desc[ *descSize ], \end_layout \begin_layout Code IPPROTO_IPV6, \end_layout \begin_layout Code IPV6_V6ONLY, \end_layout \begin_layout Code &v6Only, \end_layout \begin_layout Code sizeof( v6Only ) ) ); \end_layout \begin_layout Code #else \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** IPV6_V6ONLY is not defined, so the socket option can't be set and \end_layout \begin_layout Code ** thus IPv4 mapped addresses can't be disabled. Print a warning \end_layout \begin_layout Code ** message and close the socket. Design note: If the \end_layout \begin_layout Code ** #if...#else...#endif construct were removed, then this program \end_layout \begin_layout Code ** would not compile (because IPV6_V6ONLY isn't defined). That's an \end_layout \begin_layout Code ** acceptable approach; IPv4 mapped addresses are certainly disabled \end_layout \begin_layout Code ** if the program can't build! However, since this program is also \end_layout \begin_layout Code ** designed to work for IPv4 sockets as well as IPv6, I decided to \end_layout \begin_layout Code ** allow the program to compile when IPV6_V6ONLY is not defined, and \end_layout \begin_layout Code ** turn it into a run-time warning rather than a compile-time error. \end_layout \begin_layout Code ** IPv4 mapped addresses are still disabled because _all_ IPv6 traffic \end_layout \begin_layout Code ** is disabled (all IPv6 sockets are closed here), but at least this \end_layout \begin_layout Code ** way the server can still service IPv4 network traffic. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): WARNING - Cannot set IPV6_V6ONLY socket " \end_layout \begin_layout Code "option. Closing IPv6 %s socket. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code ai->ai_protocol == IPPROTO_TCP ? "TCP" : "UDP" ); \end_layout \begin_layout Code CHK( close( desc[ *descSize ] ) ); \end_layout \begin_layout Code continue; /* Go to top of FOR loop w/o updating *descSize! */ \end_layout \begin_layout Code #endif /* IPV6_V6ONLY */ \end_layout \begin_layout Code } /* End IF this is an IPv6 socket. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Bind the socket. Again, the info from the addrinfo structure is used. \end_layout \begin_layout Code */ \end_layout \begin_layout Code CHK( bind( desc[ *descSize ], \end_layout \begin_layout Code ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** If this is a TCP socket, put the socket into passive listening mode \end_layout \begin_layout Code ** (listen is only valid on connection-oriented sockets). \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ai->ai_socktype == SOCK_STREAM ) \end_layout \begin_layout Code { \end_layout \begin_layout Code CHK( listen( desc[ *descSize ], \end_layout \begin_layout Code MAXCONNQLEN ) ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Socket set up okay. Bump index to next descriptor array element. \end_layout \begin_layout Code */ \end_layout \begin_layout Code *descSize += 1; \end_layout \begin_layout Code } /* End FOR each address info structure returned. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Dummy check for unused address records. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose && ( ai != NULL ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): WARNING - Some address records were " \end_layout \begin_layout Code "not processed due to insufficient array space. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__ ); \end_layout \begin_layout Code } /* End IF verbose and some address records remain unprocessed. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Clean up. \end_layout \begin_layout Code */ \end_layout \begin_layout Code freeaddrinfo( aiHead ); \end_layout \begin_layout Code return 0; \end_layout \begin_layout Code } /* End openSckt() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: tod \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Listen on a set of sockets and send the current time-of-day to any \end_layout \begin_layout Code * clients. This function never returns. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * tSckt - Array of TCP socket descriptors on which to listen. \end_layout \begin_layout Code * tScktSize - Size of the tSckt array (nbr of elements). \end_layout \begin_layout Code * uSckt - Array of UDP socket descriptors on which to listen. \end_layout \begin_layout Code * uScktSize - Size of the uSckt array (nbr of elements). \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: None. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static void tod( int tSckt[ ], \end_layout \begin_layout Code size_t tScktSize, \end_layout \begin_layout Code int uSckt[ ], \end_layout \begin_layout Code size_t uScktSize ) \end_layout \begin_layout Code { \end_layout \begin_layout Code char bfr[ 256 ]; \end_layout \begin_layout Code ssize_t count; \end_layout \begin_layout Code struct pollfd *desc; \end_layout \begin_layout Code size_t descSize = tScktSize + uScktSize; \end_layout \begin_layout Code int idx; \end_layout \begin_layout Code int newSckt; \end_layout \begin_layout Code struct sockaddr *sadr; \end_layout \begin_layout Code socklen_t sadrLen; \end_layout \begin_layout Code struct sockaddr_storage sockStor; \end_layout \begin_layout Code int status; \end_layout \begin_layout Code size_t timeLen; \end_layout \begin_layout Code char *timeStr; \end_layout \begin_layout Code time_t timeVal; \end_layout \begin_layout Code ssize_t wBytes; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Allocate memory for the poll(2) array. \end_layout \begin_layout Code */ \end_layout \begin_layout Code desc = malloc( descSize * sizeof( struct pollfd ) ); \end_layout \begin_layout Code if ( desc == NULL ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code strerror( ENOMEM ) ); \end_layout \begin_layout Code exit( 1 ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Initialize the poll(2) array. \end_layout \begin_layout Code */ \end_layout \begin_layout Code for ( idx = 0; idx < descSize; idx++ ) \end_layout \begin_layout Code { \end_layout \begin_layout Code desc[ idx ].fd = idx < tScktSize ? tSckt[ idx ] \end_layout \begin_layout Code : uSckt[ idx - tScktSize ]; \end_layout \begin_layout Code desc[ idx ].events = POLLIN; \end_layout \begin_layout Code desc[ idx ].revents = 0; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Main time-of-day server loop. Handles both TCP & UDP requests. This is \end_layout \begin_layout Code ** an interative server, and all requests are handled directly within the \end_layout \begin_layout Code ** main loop. \end_layout \begin_layout Code */ \end_layout \begin_layout Code while ( true ) /* Do forever. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Wait for activity on one of the sockets. The DO..WHILE construct is \end_layout \begin_layout Code ** used to restart the system call in the event the process is \end_layout \begin_layout Code ** interrupted by a signal. \end_layout \begin_layout Code */ \end_layout \begin_layout Code do \end_layout \begin_layout Code { \end_layout \begin_layout Code status = poll( desc, \end_layout \begin_layout Code descSize, \end_layout \begin_layout Code -1 /* Wait indefinitely for input. */ ); \end_layout \begin_layout Code } while ( ( status < 0 ) && ( errno == EINTR ) ); \end_layout \begin_layout Code CHK( status ); /* Check for a bona fide system call error. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Get the current time. \end_layout \begin_layout Code */ \end_layout \begin_layout Code timeVal = time( NULL ); \end_layout \begin_layout Code timeStr = ctime( &timeVal ); \end_layout \begin_layout Code timeLen = strlen( timeStr ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Indicate that there is new network activity. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code char *s = malloc( timeLen+1 ); \end_layout \begin_layout Code strcpy( s, timeStr ); \end_layout \begin_layout Code s[ timeLen-1 ] = ' \backslash 0'; /* Overwrite ' \backslash n' in date string. */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: New network activity on %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code s ); \end_layout \begin_layout Code free( s ); \end_layout \begin_layout Code } /* End IF verbose. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process sockets with input available. \end_layout \begin_layout Code */ \end_layout \begin_layout Code for ( idx = 0; idx < descSize; idx++ ) \end_layout \begin_layout Code { \end_layout \begin_layout Code switch ( desc[ idx ].revents ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 0: /* No activity on this socket; try the next. */ \end_layout \begin_layout Code continue; \end_layout \begin_layout Code case POLLIN: /* Network activity. Go process it. */ \end_layout \begin_layout Code break; \end_layout \begin_layout Code default: /* Invalid poll events. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Invalid poll event (0x%02X). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code desc[ idx ].revents ); \end_layout \begin_layout Code exit( 1 ); \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on returned poll events. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Determine if this is a TCP request or UDP request. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( idx < tScktSize ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** TCP connection requested. Accept it. Notice the use of \end_layout \begin_layout Code ** the sockaddr_storage data type. \end_layout \begin_layout Code */ \end_layout \begin_layout Code sadrLen = sizeof( sockStor ); \end_layout \begin_layout Code sadr = (struct sockaddr*) &sockStor; \end_layout \begin_layout Code CHK( newSckt = accept( desc[ idx ].fd, \end_layout \begin_layout Code sadr, \end_layout \begin_layout Code &sadrLen ) ); \end_layout \begin_layout Code CHK( shutdown( newSckt, /* Server never recv's anything. */ \end_layout \begin_layout Code SHUT_RD ) ); \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the socket address of the remote client. Begin with \end_layout \begin_layout Code ** the address-independent fields. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "Sockaddr info for new TCP client: \backslash n" \end_layout \begin_layout Code " sa_family = %d (AF_INET = %d, AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " addr len = %d (sockaddr_in = %d, " \end_layout \begin_layout Code "sockaddr_in6 = %d) \backslash n", \end_layout \begin_layout Code sadr->sa_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code sadrLen, \end_layout \begin_layout Code sizeof( struct sockaddr_in ), \end_layout \begin_layout Code sizeof( struct sockaddr_in6 ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address-specific fields. \end_layout \begin_layout Code */ \end_layout \begin_layout Code getnameinfo( sadr, \end_layout \begin_layout Code sadrLen, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code sizeof( hostBfr ), \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code sizeof( servBfr ), \end_layout \begin_layout Code NI_NUMERICHOST | NI_NUMERICSERV ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Notice that we're switching on an address family now, not a \end_layout \begin_layout Code ** protocol family. \end_layout \begin_layout Code */ \end_layout \begin_layout Code switch ( sadr->sa_family ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case AF_INET: /* IPv4 address. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in *p = (struct sockaddr_in*) sadr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " sin_addr = sin_family: %d \backslash n" \end_layout \begin_layout Code " sin_addr: %s \backslash n" \end_layout \begin_layout Code " sin_port: %s \backslash n", \end_layout \begin_layout Code p->sin_family, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv4. */ \end_layout \begin_layout Code case AF_INET6: /* IPv6 address. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in6 *p = (struct sockaddr_in6*) sadr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " sin6_addr = sin6_family: %d \backslash n" \end_layout \begin_layout Code " sin6_addr: %s \backslash n" \end_layout \begin_layout Code " sin6_port: %s \backslash n" \end_layout \begin_layout Code " sin6_flowinfo: %d \backslash n" \end_layout \begin_layout Code " sin6_scope_id: %d \backslash n", \end_layout \begin_layout Code p->sin6_family, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code p->sin6_flowinfo, \end_layout \begin_layout Code p->sin6_scope_id ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv6. */ \end_layout \begin_layout Code default: /* Can never get here, but for completeness. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown address " \end_layout \begin_layout Code "family (%d). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code sadr->sa_family ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End DEFAULT case (unknown address family). */ \end_layout \begin_layout Code } /* End SWITCH on address family. */ \end_layout \begin_layout Code } /* End IF verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Send the TOD to the client. \end_layout \begin_layout Code */ \end_layout \begin_layout Code wBytes = timeLen; \end_layout \begin_layout Code while ( wBytes > 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code do \end_layout \begin_layout Code { \end_layout \begin_layout Code count = write( newSckt, \end_layout \begin_layout Code timeStr, \end_layout \begin_layout Code wBytes ); \end_layout \begin_layout Code } while ( ( count < 0 ) && ( errno == EINTR ) ); \end_layout \begin_layout Code CHK( count ); /* Check for a bona fide error. */ \end_layout \begin_layout Code wBytes -= count; \end_layout \begin_layout Code } /* End WHILE there is data to send. */ \end_layout \begin_layout Code CHK( close( newSckt ) ); \end_layout \begin_layout Code } /* End IF this was a TCP connection request. */ \end_layout \begin_layout Code else \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** This is a UDP socket, and a datagram is available. The funny \end_layout \begin_layout Code ** thing about UDP requests is that this server doesn't require any \end_layout \begin_layout Code ** client input; but it can't send the TOD unless it knows a client \end_layout \begin_layout Code ** wants the data, and the only way that can occur with UDP is if \end_layout \begin_layout Code ** the server receives a datagram from the client. Thus, the \end_layout \begin_layout Code ** server must receive _something_, but the content of the datagram \end_layout \begin_layout Code ** is irrelevant. Read in the datagram. Again note the use of \end_layout \begin_layout Code ** sockaddr_storage to receive the address. \end_layout \begin_layout Code */ \end_layout \begin_layout Code sadrLen = sizeof( sockStor ); \end_layout \begin_layout Code sadr = (struct sockaddr*) &sockStor; \end_layout \begin_layout Code CHK( count = recvfrom( desc[ idx ].fd, \end_layout \begin_layout Code bfr, \end_layout \begin_layout Code sizeof( bfr ), \end_layout \begin_layout Code 0, \end_layout \begin_layout Code sadr, \end_layout \begin_layout Code &sadrLen ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display whatever was received on stdout. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code ssize_t rBytes = count; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: UDP datagram received (%d bytes). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code count ); \end_layout \begin_layout Code while ( count > 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fputc( bfr[ rBytes - count-- ], \end_layout \begin_layout Code stdout ); \end_layout \begin_layout Code } \end_layout \begin_layout Code if ( bfr[ rBytes-1 ] != ' \backslash n' ) \end_layout \begin_layout Code fputc( ' \backslash n', stdout ); /* Newline also flushes stdout. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the socket address of the remote client. Address- \end_layout \begin_layout Code ** independent fields first. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "Remote client's sockaddr info: \backslash n" \end_layout \begin_layout Code " sa_family = %d (AF_INET = %d, AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " addr len = %d (sockaddr_in = %d, " \end_layout \begin_layout Code "sockaddr_in6 = %d) \backslash n", \end_layout \begin_layout Code sadr->sa_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code sadrLen, \end_layout \begin_layout Code sizeof( struct sockaddr_in ), \end_layout \begin_layout Code sizeof( struct sockaddr_in6 ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address-specific information. \end_layout \begin_layout Code */ \end_layout \begin_layout Code getnameinfo( sadr, \end_layout \begin_layout Code sadrLen, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code sizeof( hostBfr ), \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code sizeof( servBfr ), \end_layout \begin_layout Code NI_NUMERICHOST | NI_NUMERICSERV ); \end_layout \begin_layout Code switch ( sadr->sa_family ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case AF_INET: /* IPv4 address. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in *p = (struct sockaddr_in*) sadr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " sin_addr = sin_family: %d \backslash n" \end_layout \begin_layout Code " sin_addr: %s \backslash n" \end_layout \begin_layout Code " sin_port: %s \backslash n", \end_layout \begin_layout Code p->sin_family, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv4 address. */ \end_layout \begin_layout Code case AF_INET6: /* IPv6 address. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code struct sockaddr_in6 *p = (struct sockaddr_in6*) sadr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " sin6_addr = sin6_family: %d \backslash n" \end_layout \begin_layout Code " sin6_addr: %s \backslash n" \end_layout \begin_layout Code " sin6_port: %s \backslash n" \end_layout \begin_layout Code " sin6_flowinfo: %d \backslash n" \end_layout \begin_layout Code " sin6_scope_id: %d \backslash n", \end_layout \begin_layout Code p->sin6_family, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code p->sin6_flowinfo, \end_layout \begin_layout Code p->sin6_scope_id ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv6 address. */ \end_layout \begin_layout Code default: /* Can never get here, but for completeness. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown address " \end_layout \begin_layout Code "family (%d). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code sadr->sa_family ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End DEFAULT case (unknown address family). */ \end_layout \begin_layout Code } /* End SWITCH on address family. */ \end_layout \begin_layout Code } /* End IF verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Send the time-of-day to the client. \end_layout \begin_layout Code */ \end_layout \begin_layout Code wBytes = timeLen; \end_layout \begin_layout Code while ( wBytes > 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code do \end_layout \begin_layout Code { \end_layout \begin_layout Code count = sendto( desc[ idx ].fd, \end_layout \begin_layout Code timeStr, \end_layout \begin_layout Code wBytes, \end_layout \begin_layout Code 0, \end_layout \begin_layout Code sadr, /* Address & address length */ \end_layout \begin_layout Code sadrLen ); /* received in recvfrom(). */ \end_layout \begin_layout Code } while ( ( count < 0 ) && ( errno == EINTR ) ); \end_layout \begin_layout Code CHK( count ); /* Check for a bona fide error. */ \end_layout \begin_layout Code wBytes -= count; \end_layout \begin_layout Code } /* End WHILE there is data to send. */ \end_layout \begin_layout Code } /* End ELSE a UDP datagram is available. */ \end_layout \begin_layout Code desc[ idx ].revents = 0; /* Clear the returned poll events. */ \end_layout \begin_layout Code } /* End FOR each socket descriptor. */ \end_layout \begin_layout Code } /* End WHILE forever. */ \end_layout \begin_layout Code } /* End tod() */ \end_layout \begin_layout Subsubsection 'Daytime' TCP Client Code \end_layout \begin_layout Standard The TCP client code is found in file tod6tc.c (time-of-day IPv6 TCP client). Once built, the TCP client may be started using the following command syntax (assuming tod6tc is the executable file): \end_layout \begin_layout Code tod6tc [-v] [-s scope_id] [host [service]] \end_layout \begin_layout Standard ARGUMENTS: \end_layout \begin_layout Description host The hostname or IP address (dotted decimal or colon-hex) of the remote host providing the service. Default is "localhost". \end_layout \begin_layout Description service The TCP service (or well-known port number) to which a connection attempt is made. Default is "daytime". \end_layout \begin_layout Standard OPTIONS: \end_layout \begin_layout Description -s This option is only meaningful for IPv6 addresses, and is used to set the scope identifier (i.e. the network interface on which to establish the connection). Default is "eth0". If host is a scoped address, this option is ignored. \end_layout \begin_layout Description -v Turn on verbose mode. \end_layout \begin_layout Standard The TCP client source code contained in tod6tc.c follows: \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * File: tod6tc.c \end_layout \begin_layout Code * Description: Contains source code for an IPv6-capable 'daytime' TCP client. \end_layout \begin_layout Code * Author: John Wenker, Sr. Software Engineer \end_layout \begin_layout Code * Performance Technologies, San Diego, USA \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** System header files. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #include /* errno declaration and error codes. */ \end_layout \begin_layout Code #include /* if_nametoindex(3). */ \end_layout \begin_layout Code #include /* getaddrinfo(3) and associated definitions. */ \end_layout \begin_layout Code #include /* sockaddr_in and sockaddr_in6 definitions. */ \end_layout \begin_layout Code #include /* printf(3) et al. */ \end_layout \begin_layout Code #include /* exit(2). */ \end_layout \begin_layout Code #include /* String manipulation and memory functions. */ \end_layout \begin_layout Code #include /* Socket functions (socket(2), connect(2), etc). */ \end_layout \begin_layout Code #include /* getopt(3), read(2), etc. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Constants & macros. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define DFLT_HOST "localhost" /* Default server name. */ \end_layout \begin_layout Code #define DFLT_SCOPE_ID "eth0" /* Default scope identifier. */ \end_layout \begin_layout Code #define DFLT_SERVICE "daytime" /* Default service name. */ \end_layout \begin_layout Code #define INVALID_DESC -1 /* Invalid file (socket) descriptor. */ \end_layout \begin_layout Code #define MAXBFRSIZE 256 /* Max bfr sz to read remote TOD. */ \end_layout \begin_layout Code #define VALIDOPTS "s:v" /* Valid command options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Type definitions (for convenience). \end_layout \begin_layout Code */ \end_layout \begin_layout Code typedef enum { false = 0, true } boolean; \end_layout \begin_layout Code typedef struct sockaddr_in sockaddr_in_t; \end_layout \begin_layout Code typedef struct sockaddr_in6 sockaddr_in6_t; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Prototypes for internal helper functions. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static int openSckt( const char *host, \end_layout \begin_layout Code const char *service, \end_layout \begin_layout Code unsigned int scopeId ); \end_layout \begin_layout Code static void tod( int sckt ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Global (within this file only) data objects. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static const char *pgmName; /* Program name (w/o directory). */ \end_layout \begin_layout Code static boolean verbose = false; /* Verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Usage macro. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define USAGE \backslash \end_layout \begin_layout Code { \backslash \end_layout \begin_layout Code fprintf( stderr, \backslash \end_layout \begin_layout Code "Usage: %s [-v] [-s scope_id] [host [service]] \backslash n", \backslash \end_layout \begin_layout Code pgmName ); \backslash \end_layout \begin_layout Code exit( 127 ); \backslash \end_layout \begin_layout Code } /* End USAGE macro. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** This "macro" (even though it's really a function) is loosely based on the \end_layout \begin_layout Code ** CHK() macro by Dr. V. Vinge (see server code). The status parameter is \end_layout \begin_layout Code ** a boolean expression indicating the return code from one of the usual system \end_layout \begin_layout Code ** calls that returns -1 on error. If a system call error occurred, an alert \end_layout \begin_layout Code ** is written to stderr. It returns a boolean value indicating success/failure \end_layout \begin_layout Code ** of the system call. \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Example: if ( !SYSCALL( "write", \end_layout \begin_layout Code ** count = write( fd, bfr, size ) ) ) \end_layout \begin_layout Code ** { \end_layout \begin_layout Code ** // Error processing... but SYSCALL() will have already taken \end_layout \begin_layout Code ** // care of dumping an error alert to stderr. \end_layout \begin_layout Code ** } \end_layout \begin_layout Code */ \end_layout \begin_layout Code static __inline boolean SYSCALL( const char *syscallName, \end_layout \begin_layout Code int lineNbr, \end_layout \begin_layout Code int status ) \end_layout \begin_layout Code { \end_layout \begin_layout Code if ( ( status == -1 ) && verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): System call failed ('%s') - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code lineNbr, \end_layout \begin_layout Code syscallName, \end_layout \begin_layout Code strerror( errno ) ); \end_layout \begin_layout Code } \end_layout \begin_layout Code return status != -1; /* True if the system call was successful. */ \end_layout \begin_layout Code } /* End SYSCALL() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: main \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Connect to a remote time-of-day service and write the remote host's TOD to \end_layout \begin_layout Code * stdout. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * The usual argc & argv parameters to a main() program. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * This function always returns zero. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code int main( int argc, \end_layout \begin_layout Code char *argv[ ] ) \end_layout \begin_layout Code { \end_layout \begin_layout Code const char *host = DFLT_HOST; \end_layout \begin_layout Code int opt; \end_layout \begin_layout Code int sckt; \end_layout \begin_layout Code unsigned int scopeId = if_nametoindex( DFLT_SCOPE_ID ); \end_layout \begin_layout Code const char *service = DFLT_SERVICE; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Determine the program name (w/o directory prefix). \end_layout \begin_layout Code */ \end_layout \begin_layout Code pgmName = (const char*) strrchr( argv[ 0 ], '/' ); \end_layout \begin_layout Code pgmName = pgmName == NULL ? argv[ 0 ] : pgmName+1; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command line options. \end_layout \begin_layout Code */ \end_layout \begin_layout Code opterr = 0; /* Turns off "invalid option" error messages. */ \end_layout \begin_layout Code while ( ( opt = getopt( argc, argv, VALIDOPTS ) ) != -1 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code switch ( opt ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 's': /* Scope identifier (IPv6 kluge). */ \end_layout \begin_layout Code { \end_layout \begin_layout Code scopeId = if_nametoindex( optarg ); \end_layout \begin_layout Code if ( scopeId == 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: Unknown network interface (%s). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code optarg ); \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code case 'v': /* Verbose mode. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code verbose = true; \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code default: \end_layout \begin_layout Code { \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on command option. */ \end_layout \begin_layout Code } /* End WHILE processing command options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command arguments. At the end of the above loop, optind is the \end_layout \begin_layout Code ** index of the first NON-option argv element. \end_layout \begin_layout Code */ \end_layout \begin_layout Code switch ( argc - optind ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 2: /* Both host & service are specified on the command line. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code service = argv[ optind + 1 ]; \end_layout \begin_layout Code /***** Fall through *****/ \end_layout \begin_layout Code } \end_layout \begin_layout Code case 1: /* Host is specified on the command line. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code host = argv[ optind ]; \end_layout \begin_layout Code /***** Fall through *****/ \end_layout \begin_layout Code } \end_layout \begin_layout Code case 0: /* Use default host & service. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code default: \end_layout \begin_layout Code { \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on number of command arguments. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Open a connection to the indicated host/service. \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Note that if all three of the following conditions are met, then the \end_layout \begin_layout Code ** scope identifier remains unresolved at this point. \end_layout \begin_layout Code ** 1) The default network interface is unknown for some reason. \end_layout \begin_layout Code ** 2) The -s option was not used on the command line. \end_layout \begin_layout Code ** 3) An IPv6 "scoped address" was not specified for the hostname on the \end_layout \begin_layout Code ** command line. \end_layout \begin_layout Code ** If the above three conditions are met, then only an IPv4 socket can be \end_layout \begin_layout Code ** opened (connect(2) fails without the scope ID properly set for IPv6 \end_layout \begin_layout Code ** sockets). \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( sckt = openSckt( host, \end_layout \begin_layout Code service, \end_layout \begin_layout Code scopeId ) ) == INVALID_DESC ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: Sorry... a connection could not be established. \backslash n", \end_layout \begin_layout Code pgmName ); \end_layout \begin_layout Code exit( 1 ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Get the remote time-of-day. \end_layout \begin_layout Code */ \end_layout \begin_layout Code tod( sckt ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Close the connection and terminate. \end_layout \begin_layout Code */ \end_layout \begin_layout Code (void) SYSCALL( "close", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code close( sckt ) ); \end_layout \begin_layout Code return 0; \end_layout \begin_layout Code } /* End main() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: openSckt \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Sets up a TCP connection to a remote server. Getaddrinfo(3) is used to \end_layout \begin_layout Code * perform lookup functions and can return multiple address records (i.e. a \end_layout \begin_layout Code * list of 'struct addrinfo' records). This function traverses the list and \end_layout \begin_layout Code * tries to establish a connection to the remote server. The function ends \end_layout \begin_layout Code * when either a connection has been established or all records in the list \end_layout \begin_layout Code * have been processed. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * host - A pointer to a character string representing the hostname or IP \end_layout \begin_layout Code * address (IPv4 or IPv6) of the remote server. \end_layout \begin_layout Code * service - A pointer to a character string representing the service name or \end_layout \begin_layout Code * well-known port number. \end_layout \begin_layout Code * scopeId - For IPv6 sockets only. This is the index corresponding to the \end_layout \begin_layout Code * network interface on which to set up the connection. This \end_layout \begin_layout Code * parameter is ignored for IPv4 sockets or when an IPv6 "scoped \end_layout \begin_layout Code * address" is specified in 'host' (i.e. where the colon-hex \end_layout \begin_layout Code * network address is augmented with the scope ID). \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * Returns the socket descriptor for the connection, or INVALID_DESC if all \end_layout \begin_layout Code * address records have been processed and a connection could not be \end_layout \begin_layout Code * established. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static int openSckt( const char *host, \end_layout \begin_layout Code const char *service, \end_layout \begin_layout Code unsigned int scopeId ) \end_layout \begin_layout Code { \end_layout \begin_layout Code struct addrinfo *ai; \end_layout \begin_layout Code int aiErr; \end_layout \begin_layout Code struct addrinfo *aiHead; \end_layout \begin_layout Code struct addrinfo hints; \end_layout \begin_layout Code sockaddr_in6_t *pSadrIn6; \end_layout \begin_layout Code int sckt; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Initialize the 'hints' structure for getaddrinfo(3). \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Notice that the 'ai_family' field is set to PF_UNSPEC, indicating to \end_layout \begin_layout Code ** return both IPv4 and IPv6 address records for the host/service. Most of \end_layout \begin_layout Code ** the time, the user isn't going to care whether an IPv4 connection or an \end_layout \begin_layout Code ** IPv6 connection is established; the user simply wants to exchange data \end_layout \begin_layout Code ** with the remote host and doesn't care how it's done. Sometimes, however, \end_layout \begin_layout Code ** the user might want to explicitly specify the type of underlying socket. \end_layout \begin_layout Code ** It is left as an exercise for the motivated reader to add a command line \end_layout \begin_layout Code ** option allowing the user to specify the IP protocol, and then process the \end_layout \begin_layout Code ** list of addresses accordingly (it's not that difficult). \end_layout \begin_layout Code */ \end_layout \begin_layout Code memset( &hints, 0, sizeof( hints ) ); \end_layout \begin_layout Code hints.ai_family = PF_UNSPEC; /* IPv4 or IPv6 records (don't care). */ \end_layout \begin_layout Code hints.ai_socktype = SOCK_STREAM; /* Connection-oriented byte stream. */ \end_layout \begin_layout Code hints.ai_protocol = IPPROTO_TCP; /* TCP transport layer protocol only. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Look up the host/service information. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( aiErr = getaddrinfo( host, \end_layout \begin_layout Code service, \end_layout \begin_layout Code &hints, \end_layout \begin_layout Code &aiHead ) ) != 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code gai_strerror( aiErr ) ); \end_layout \begin_layout Code return INVALID_DESC; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Go through the list and try to open a connection. Continue until either \end_layout \begin_layout Code ** a connection is established or the entire list is exhausted. \end_layout \begin_layout Code */ \end_layout \begin_layout Code for ( ai = aiHead, sckt = INVALID_DESC; \end_layout \begin_layout Code ( ai != NULL ) && ( sckt == INVALID_DESC ); \end_layout \begin_layout Code ai = ai->ai_next ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** IPv6 kluge. Make sure the scope ID is set. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ai->ai_family == PF_INET6 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6 = (sockaddr_in6_t*) ai->ai_addr; \end_layout \begin_layout Code if ( pSadrIn6->sin6_scope_id == 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6->sin6_scope_id = scopeId; \end_layout \begin_layout Code } /* End IF the scope ID wasn't set. */ \end_layout \begin_layout Code } /* End IPv6 kluge. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address info for the remote host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Temporary character string buffers for host & service. \end_layout \begin_layout Code */ \end_layout \begin_layout Code char hostBfr[ NI_MAXHOST ]; \end_layout \begin_layout Code char servBfr[ NI_MAXSERV ]; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address information just fetched. Start with the \end_layout \begin_layout Code ** common (protocol-independent) stuff first. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "Address info: \backslash n" \end_layout \begin_layout Code " ai_flags = 0x%02X \backslash n" \end_layout \begin_layout Code " ai_family = %d (PF_INET = %d, PF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " ai_socktype = %d (SOCK_STREAM = %d, SOCK_DGRAM = %d) \backslash n" \end_layout \begin_layout Code " ai_protocol = %d (IPPROTO_TCP = %d, IPPROTO_UDP = %d) \backslash n" \end_layout \begin_layout Code " ai_addrlen = %d (sockaddr_in = %d, " \end_layout \begin_layout Code "sockaddr_in6 = %d) \backslash n", \end_layout \begin_layout Code ai->ai_flags, \end_layout \begin_layout Code ai->ai_family, \end_layout \begin_layout Code PF_INET, \end_layout \begin_layout Code PF_INET6, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code SOCK_STREAM, \end_layout \begin_layout Code SOCK_DGRAM, \end_layout \begin_layout Code ai->ai_protocol, \end_layout \begin_layout Code IPPROTO_TCP, \end_layout \begin_layout Code IPPROTO_UDP, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code sizeof( struct sockaddr_in ), \end_layout \begin_layout Code sizeof( struct sockaddr_in6 ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the protocol-specific formatted address. \end_layout \begin_layout Code */ \end_layout \begin_layout Code getnameinfo( ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code sizeof( hostBfr ), \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code sizeof( servBfr ), \end_layout \begin_layout Code NI_NUMERICHOST | NI_NUMERICSERV ); \end_layout \begin_layout Code switch ( ai->ai_family ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case PF_INET: /* IPv4 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code sockaddr_in_t *pSadrIn = (sockaddr_in_t*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin_addr: %s \backslash n" \end_layout \begin_layout Code " sin_port: %s \backslash n", \end_layout \begin_layout Code pSadrIn->sin_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv4 record. */ \end_layout \begin_layout Code case PF_INET6: /* IPv6 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6 = (sockaddr_in6_t*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin6_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin6_addr: %s \backslash n" \end_layout \begin_layout Code " sin6_port: %s \backslash n" \end_layout \begin_layout Code " sin6_flowinfo: %d \backslash n" \end_layout \begin_layout Code " sin6_scope_id: %d \backslash n", \end_layout \begin_layout Code pSadrIn6->sin6_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code pSadrIn6->sin6_flowinfo, \end_layout \begin_layout Code pSadrIn6->sin6_scope_id ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv6 record. */ \end_layout \begin_layout Code default: /* Can never get here, but just for completeness. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown protocol family (%d). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code ai->ai_family ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End DEFAULT case (unknown protocol family). */ \end_layout \begin_layout Code } /* End SWITCH on protocol family. */ \end_layout \begin_layout Code } /* End IF verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Create a socket. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "socket", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code sckt = socket( ai->ai_family, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code ai->ai_protocol ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code sckt = INVALID_DESC; \end_layout \begin_layout Code continue; /* Try the next address record in the list. */ \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Connect to the remote host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "connect", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code connect( sckt, \end_layout \begin_layout Code ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code (void) close( sckt ); /* Could use SYSCALL() again here, but why? */ \end_layout \begin_layout Code sckt = INVALID_DESC; \end_layout \begin_layout Code continue; /* Try the next address record in the list. */ \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End FOR each address record returned by getaddrinfo(3). */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Clean up & return. \end_layout \begin_layout Code */ \end_layout \begin_layout Code freeaddrinfo( aiHead ); \end_layout \begin_layout Code return sckt; \end_layout \begin_layout Code } /* End openSckt() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: tod \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Receive the time-of-day from the remote server and write it to stdout. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * sckt - The socket descriptor for the connection. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: None. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static void tod( int sckt ) \end_layout \begin_layout Code { \end_layout \begin_layout Code char bfr[ MAXBFRSIZE+1 ]; \end_layout \begin_layout Code int inBytes; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** The client never sends anything, so shut down the write side of the \end_layout \begin_layout Code ** connection. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "shutdown", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code shutdown( sckt, SHUT_WR ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code return; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Read the time-of-day from the remote host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code do \end_layout \begin_layout Code { \end_layout \begin_layout Code if ( !SYSCALL( "read", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code inBytes = read( sckt, \end_layout \begin_layout Code bfr, \end_layout \begin_layout Code MAXBFRSIZE ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code return; \end_layout \begin_layout Code } \end_layout \begin_layout Code bfr[ inBytes ] = ' \backslash 0'; /* Null-terminate the received string. */ \end_layout \begin_layout Code fputs( bfr, stdout ); /* Null string if EOF (inBytes == 0). */ \end_layout \begin_layout Code } while ( inBytes > 0 ); \end_layout \begin_layout Code fflush( stdout ); \end_layout \begin_layout Code } /* End tod() */ \end_layout \begin_layout Subsubsection 'Daytime' UDP Client Code \end_layout \begin_layout Standard The UDP client code is found in file tod6uc.c (time-of-day IPv6 UDP client). It is almost an exact duplicate of the TCP client (and in fact was derived from it), but is included in this HowTo for completeness. Once built, the UDP client may be started using the following command syntax (assuming tod6uc is the executable file): \end_layout \begin_layout Code tod6uc [-v] [-s scope_id] [host [service]] \end_layout \begin_layout Standard ARGUMENTS: \end_layout \begin_layout Description host The hostname or IP address (dotted decimal or colon-hex) of the remote host providing the service. Default is "localhost". \end_layout \begin_layout Description service The UDP service (or well-known port number) to which datagrams are sent. Default is "daytime". \end_layout \begin_layout Standard OPTIONS: \end_layout \begin_layout Description -s This option is only meaningful for IPv6 addresses, and is used to set the scope identifier (i.e. the network interface on which to exchange datagrams). Default is "eth0". If host is a scoped address, this option is ignored. \end_layout \begin_layout Description -v Turn on verbose mode. \end_layout \begin_layout Standard The UDP client source code contained in tod6uc.c follows: \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * File: tod6uc.c \end_layout \begin_layout Code * Description: Contains source code for an IPv6-capable 'daytime' UDP client. \end_layout \begin_layout Code * Author: John Wenker, Sr. Software Engineer \end_layout \begin_layout Code * Performance Technologies, San Diego, USA \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** System header files. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #include /* errno declaration and error codes. */ \end_layout \begin_layout Code #include /* if_nametoindex(3). */ \end_layout \begin_layout Code #include /* getaddrinfo(3) and associated definitions. */ \end_layout \begin_layout Code #include /* sockaddr_in and sockaddr_in6 definitions. */ \end_layout \begin_layout Code #include /* printf(3) et al. */ \end_layout \begin_layout Code #include /* exit(2). */ \end_layout \begin_layout Code #include /* String manipulation and memory functions. */ \end_layout \begin_layout Code #include /* Socket functions (socket(2), connect(2), etc). */ \end_layout \begin_layout Code #include /* getopt(3), recvfrom(2), sendto(2), etc. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Constants & macros. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define DFLT_HOST "localhost" /* Default server name. */ \end_layout \begin_layout Code #define DFLT_SCOPE_ID "eth0" /* Default scope identifier. */ \end_layout \begin_layout Code #define DFLT_SERVICE "daytime" /* Default service name. */ \end_layout \begin_layout Code #define INVALID_DESC -1 /* Invalid file (socket) descriptor. */ \end_layout \begin_layout Code #define MAXBFRSIZE 256 /* Max bfr sz to read remote TOD. */ \end_layout \begin_layout Code #define VALIDOPTS "s:v" /* Valid command options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Type definitions (for convenience). \end_layout \begin_layout Code */ \end_layout \begin_layout Code typedef enum { false = 0, true } boolean; \end_layout \begin_layout Code typedef struct sockaddr_in sockaddr_in_t; \end_layout \begin_layout Code typedef struct sockaddr_in6 sockaddr_in6_t; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Prototypes for internal helper functions. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static int openSckt( const char *host, \end_layout \begin_layout Code const char *service, \end_layout \begin_layout Code unsigned int scopeId ); \end_layout \begin_layout Code static void tod( int sckt ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Global (within this file only) data objects. \end_layout \begin_layout Code */ \end_layout \begin_layout Code static const char *pgmName; /* Program name (w/o directory). */ \end_layout \begin_layout Code static boolean verbose = false; /* Verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Usage macro. \end_layout \begin_layout Code */ \end_layout \begin_layout Code #define USAGE \backslash \end_layout \begin_layout Code { \backslash \end_layout \begin_layout Code fprintf( stderr, \backslash \end_layout \begin_layout Code "Usage: %s [-v] [-s scope_id] [host [service]] \backslash n", \backslash \end_layout \begin_layout Code pgmName ); \backslash \end_layout \begin_layout Code exit( 127 ); \backslash \end_layout \begin_layout Code } /* End USAGE macro. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** This "macro" (even though it's really a function) is loosely based on the \end_layout \begin_layout Code ** CHK() macro by Dr. V. Vinge (see server code). The status parameter is \end_layout \begin_layout Code ** a boolean expression indicating the return code from one of the usual system \end_layout \begin_layout Code ** calls that returns -1 on error. If a system call error occurred, an alert \end_layout \begin_layout Code ** is written to stderr. It returns a boolean value indicating success/failure \end_layout \begin_layout Code ** of the system call. \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Example: if ( !SYSCALL( "write", \end_layout \begin_layout Code ** count = write( fd, bfr, size ) ) ) \end_layout \begin_layout Code ** { \end_layout \begin_layout Code ** // Error processing... but SYSCALL() will have already taken \end_layout \begin_layout Code ** // care of dumping an error alert to stderr. \end_layout \begin_layout Code ** } \end_layout \begin_layout Code */ \end_layout \begin_layout Code static __inline boolean SYSCALL( const char *syscallName, \end_layout \begin_layout Code int lineNbr, \end_layout \begin_layout Code int status ) \end_layout \begin_layout Code { \end_layout \begin_layout Code if ( ( status == -1 ) && verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): System call failed ('%s') - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code lineNbr, \end_layout \begin_layout Code syscallName, \end_layout \begin_layout Code strerror( errno ) ); \end_layout \begin_layout Code } \end_layout \begin_layout Code return status != -1; /* True if the system call was successful. */ \end_layout \begin_layout Code } /* End SYSCALL() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: main \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Connect to a remote time-of-day service and write the remote host's TOD to \end_layout \begin_layout Code * stdout. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * The usual argc & argv parameters to a main() program. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * This function always returns zero. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code int main( int argc, \end_layout \begin_layout Code char *argv[ ] ) \end_layout \begin_layout Code { \end_layout \begin_layout Code const char *host = DFLT_HOST; \end_layout \begin_layout Code int opt; \end_layout \begin_layout Code int sckt; \end_layout \begin_layout Code unsigned int scopeId = if_nametoindex( DFLT_SCOPE_ID ); \end_layout \begin_layout Code const char *service = DFLT_SERVICE; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Determine the program name (w/o directory prefix). \end_layout \begin_layout Code */ \end_layout \begin_layout Code pgmName = (const char*) strrchr( argv[ 0 ], '/' ); \end_layout \begin_layout Code pgmName = pgmName == NULL ? argv[ 0 ] : pgmName+1; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command line options. \end_layout \begin_layout Code */ \end_layout \begin_layout Code opterr = 0; /* Turns off "invalid option" error messages. */ \end_layout \begin_layout Code while ( ( opt = getopt( argc, argv, VALIDOPTS ) ) != -1 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code switch ( opt ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 's': /* Scope identifier (IPv6 kluge). */ \end_layout \begin_layout Code { \end_layout \begin_layout Code scopeId = if_nametoindex( optarg ); \end_layout \begin_layout Code if ( scopeId == 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: Unknown network interface (%s). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code optarg ); \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code case 'v': /* Verbose mode. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code verbose = true; \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code default: \end_layout \begin_layout Code { \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on command option. */ \end_layout \begin_layout Code } /* End WHILE processing command options. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Process command arguments. At the end of the above loop, optind is the \end_layout \begin_layout Code ** index of the first NON-option argv element. \end_layout \begin_layout Code */ \end_layout \begin_layout Code switch ( argc - optind ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case 2: /* Both host & service are specified on the command line. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code service = argv[ optind + 1 ]; \end_layout \begin_layout Code /***** Fall through *****/ \end_layout \begin_layout Code } \end_layout \begin_layout Code case 1: /* Host is specified on the command line. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code host = argv[ optind ]; \end_layout \begin_layout Code /***** Fall through *****/ \end_layout \begin_layout Code } \end_layout \begin_layout Code case 0: /* Use default host & service. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code break; \end_layout \begin_layout Code } \end_layout \begin_layout Code default: \end_layout \begin_layout Code { \end_layout \begin_layout Code USAGE; \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End SWITCH on number of command arguments. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Open a connection to the indicated host/service. \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Note that if all three of the following conditions are met, then the \end_layout \begin_layout Code ** scope identifier remains unresolved at this point. \end_layout \begin_layout Code ** 1) The default network interface is unknown for some reason. \end_layout \begin_layout Code ** 2) The -s option was not used on the command line. \end_layout \begin_layout Code ** 3) An IPv6 "scoped address" was not specified for the hostname on the \end_layout \begin_layout Code ** command line. \end_layout \begin_layout Code ** If the above three conditions are met, then only an IPv4 socket can be \end_layout \begin_layout Code ** opened (connect(2) fails without the scope ID properly set for IPv6 \end_layout \begin_layout Code ** sockets). \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( sckt = openSckt( host, \end_layout \begin_layout Code service, \end_layout \begin_layout Code scopeId ) ) == INVALID_DESC ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s: Sorry... a connectionless socket could " \end_layout \begin_layout Code "not be set up. \backslash n", \end_layout \begin_layout Code pgmName ); \end_layout \begin_layout Code exit( 1 ); \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Get the remote time-of-day. \end_layout \begin_layout Code */ \end_layout \begin_layout Code tod( sckt ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Close the connection and terminate. \end_layout \begin_layout Code */ \end_layout \begin_layout Code (void) SYSCALL( "close", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code close( sckt ) ); \end_layout \begin_layout Code return 0; \end_layout \begin_layout Code } /* End main() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: openSckt \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Sets up a UDP socket to a remote server. Getaddrinfo(3) is used to \end_layout \begin_layout Code * perform lookup functions and can return multiple address records (i.e. a \end_layout \begin_layout Code * list of 'struct addrinfo' records). This function traverses the list and \end_layout \begin_layout Code * tries to establish a connection to the remote server. The function ends \end_layout \begin_layout Code * when either a connection has been established or all records in the list \end_layout \begin_layout Code * have been processed. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * host - A pointer to a character string representing the hostname or IP \end_layout \begin_layout Code * address (IPv4 or IPv6) of the remote server. \end_layout \begin_layout Code * service - A pointer to a character string representing the service name or \end_layout \begin_layout Code * well-known port number. \end_layout \begin_layout Code * scopeId - For IPv6 sockets only. This is the index corresponding to the \end_layout \begin_layout Code * network interface on which to exchange datagrams. This \end_layout \begin_layout Code * parameter is ignored for IPv4 sockets or when an IPv6 "scoped \end_layout \begin_layout Code * address" is specified in 'host' (i.e. where the colon-hex \end_layout \begin_layout Code * network address is augmented with the scope ID). \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: \end_layout \begin_layout Code * Returns the socket descriptor for the connection, or INVALID_DESC if all \end_layout \begin_layout Code * address records have been processed and a socket could not be initialized. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static int openSckt( const char *host, \end_layout \begin_layout Code const char *service, \end_layout \begin_layout Code unsigned int scopeId ) \end_layout \begin_layout Code { \end_layout \begin_layout Code struct addrinfo *ai; \end_layout \begin_layout Code int aiErr; \end_layout \begin_layout Code struct addrinfo *aiHead; \end_layout \begin_layout Code struct addrinfo hints; \end_layout \begin_layout Code sockaddr_in6_t *pSadrIn6; \end_layout \begin_layout Code int sckt; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Initialize the 'hints' structure for getaddrinfo(3). \end_layout \begin_layout Code ** \end_layout \begin_layout Code ** Notice that the 'ai_family' field is set to PF_UNSPEC, indicating to \end_layout \begin_layout Code ** return both IPv4 and IPv6 address records for the host/service. Most of \end_layout \begin_layout Code ** the time, the user isn't going to care whether an IPv4 connection or an \end_layout \begin_layout Code ** IPv6 connection is established; the user simply wants to exchange data \end_layout \begin_layout Code ** with the remote host and doesn't care how it's done. Sometimes, however, \end_layout \begin_layout Code ** the user might want to explicitly specify the type of underlying socket. \end_layout \begin_layout Code ** It is left as an exercise for the motivated reader to add a command line \end_layout \begin_layout Code ** option allowing the user to specify the IP protocol, and then process the \end_layout \begin_layout Code ** list of addresses accordingly (it's not that difficult). \end_layout \begin_layout Code */ \end_layout \begin_layout Code memset( &hints, 0, sizeof( hints ) ); \end_layout \begin_layout Code hints.ai_family = PF_UNSPEC; /* IPv4 or IPv6 records (don't care). */ \end_layout \begin_layout Code hints.ai_socktype = SOCK_DGRAM; /* Connectionless communication. */ \end_layout \begin_layout Code hints.ai_protocol = IPPROTO_UDP; /* UDP transport layer protocol only. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Look up the host/service information. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ( aiErr = getaddrinfo( host, \end_layout \begin_layout Code service, \end_layout \begin_layout Code &hints, \end_layout \begin_layout Code &aiHead ) ) != 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - %s. \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code gai_strerror( aiErr ) ); \end_layout \begin_layout Code return INVALID_DESC; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Go through the list and try to open a connection. Continue until either \end_layout \begin_layout Code ** a connection is established or the entire list is exhausted. \end_layout \begin_layout Code */ \end_layout \begin_layout Code for ( ai = aiHead, sckt = INVALID_DESC; \end_layout \begin_layout Code ( ai != NULL ) && ( sckt == INVALID_DESC ); \end_layout \begin_layout Code ai = ai->ai_next ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** IPv6 kluge. Make sure the scope ID is set. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( ai->ai_family == PF_INET6 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6 = (sockaddr_in6_t*) ai->ai_addr; \end_layout \begin_layout Code if ( pSadrIn6->sin6_scope_id == 0 ) \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6->sin6_scope_id = scopeId; \end_layout \begin_layout Code } /* End IF the scope ID wasn't set. */ \end_layout \begin_layout Code } /* End IPv6 kluge. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address info for the remote host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( verbose ) \end_layout \begin_layout Code { \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Temporary character string buffers for host & service. \end_layout \begin_layout Code */ \end_layout \begin_layout Code char hostBfr[ NI_MAXHOST ]; \end_layout \begin_layout Code char servBfr[ NI_MAXSERV ]; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the address information just fetched. Start with the \end_layout \begin_layout Code ** common (protocol-independent) stuff first. \end_layout \begin_layout Code */ \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "Address info: \backslash n" \end_layout \begin_layout Code " ai_flags = 0x%02X \backslash n" \end_layout \begin_layout Code " ai_family = %d (PF_INET = %d, PF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " ai_socktype = %d (SOCK_STREAM = %d, SOCK_DGRAM = %d) \backslash n" \end_layout \begin_layout Code " ai_protocol = %d (IPPROTO_TCP = %d, IPPROTO_UDP = %d) \backslash n" \end_layout \begin_layout Code " ai_addrlen = %d (sockaddr_in = %d, " \end_layout \begin_layout Code "sockaddr_in6 = %d) \backslash n", \end_layout \begin_layout Code ai->ai_flags, \end_layout \begin_layout Code ai->ai_family, \end_layout \begin_layout Code PF_INET, \end_layout \begin_layout Code PF_INET6, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code SOCK_STREAM, \end_layout \begin_layout Code SOCK_DGRAM, \end_layout \begin_layout Code ai->ai_protocol, \end_layout \begin_layout Code IPPROTO_TCP, \end_layout \begin_layout Code IPPROTO_UDP, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code sizeof( struct sockaddr_in ), \end_layout \begin_layout Code sizeof( struct sockaddr_in6 ) ); \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Display the protocol-specific formatted address. \end_layout \begin_layout Code */ \end_layout \begin_layout Code getnameinfo( ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code sizeof( hostBfr ), \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code sizeof( servBfr ), \end_layout \begin_layout Code NI_NUMERICHOST | NI_NUMERICSERV ); \end_layout \begin_layout Code switch ( ai->ai_family ) \end_layout \begin_layout Code { \end_layout \begin_layout Code case PF_INET: /* IPv4 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code sockaddr_in_t *pSadrIn = (sockaddr_in_t*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin_addr: %s \backslash n" \end_layout \begin_layout Code " sin_port: %s \backslash n", \end_layout \begin_layout Code pSadrIn->sin_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv4 record. */ \end_layout \begin_layout Code case PF_INET6: /* IPv6 address record. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code pSadrIn6 = (sockaddr_in6_t*) ai->ai_addr; \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code " ai_addr = sin6_family: %d (AF_INET = %d, " \end_layout \begin_layout Code "AF_INET6 = %d) \backslash n" \end_layout \begin_layout Code " sin6_addr: %s \backslash n" \end_layout \begin_layout Code " sin6_port: %s \backslash n" \end_layout \begin_layout Code " sin6_flowinfo: %d \backslash n" \end_layout \begin_layout Code " sin6_scope_id: %d \backslash n", \end_layout \begin_layout Code pSadrIn6->sin6_family, \end_layout \begin_layout Code AF_INET, \end_layout \begin_layout Code AF_INET6, \end_layout \begin_layout Code hostBfr, \end_layout \begin_layout Code servBfr, \end_layout \begin_layout Code pSadrIn6->sin6_flowinfo, \end_layout \begin_layout Code pSadrIn6->sin6_scope_id ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End CASE of IPv6 record. */ \end_layout \begin_layout Code default: /* Can never get here, but just for completeness. */ \end_layout \begin_layout Code { \end_layout \begin_layout Code fprintf( stderr, \end_layout \begin_layout Code "%s (line %d): ERROR - Unknown protocol family (%d). \backslash n", \end_layout \begin_layout Code pgmName, \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code ai->ai_family ); \end_layout \begin_layout Code break; \end_layout \begin_layout Code } /* End DEFAULT case (unknown protocol family). */ \end_layout \begin_layout Code } /* End SWITCH on protocol family. */ \end_layout \begin_layout Code } /* End IF verbose mode. */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Create a socket. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "socket", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code sckt = socket( ai->ai_family, \end_layout \begin_layout Code ai->ai_socktype, \end_layout \begin_layout Code ai->ai_protocol ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code sckt = INVALID_DESC; \end_layout \begin_layout Code continue; /* Try the next address record in the list. */ \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Set the target destination for the remote host on this socket. That \end_layout \begin_layout Code ** is, this socket only communicates with the specified host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "connect", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code connect( sckt, \end_layout \begin_layout Code ai->ai_addr, \end_layout \begin_layout Code ai->ai_addrlen ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code (void) close( sckt ); /* Could use SYSCALL() again here, but why? */ \end_layout \begin_layout Code sckt = INVALID_DESC; \end_layout \begin_layout Code continue; /* Try the next address record in the list. */ \end_layout \begin_layout Code } \end_layout \begin_layout Code } /* End FOR each address record returned by getaddrinfo(3). */ \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Clean up & return. \end_layout \begin_layout Code */ \end_layout \begin_layout Code freeaddrinfo( aiHead ); \end_layout \begin_layout Code return sckt; \end_layout \begin_layout Code } /* End openSckt() */ \end_layout \begin_layout Code /****************************************************************************** \end_layout \begin_layout Code * Function: tod \end_layout \begin_layout Code * \end_layout \begin_layout Code * Description: \end_layout \begin_layout Code * Receive the time-of-day from the remote server and write it to stdout. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Parameters: \end_layout \begin_layout Code * sckt - The socket descriptor for the connection. \end_layout \begin_layout Code * \end_layout \begin_layout Code * Return Value: None. \end_layout \begin_layout Code ******************************************************************************/ \end_layout \begin_layout Code static void tod( int sckt ) \end_layout \begin_layout Code { \end_layout \begin_layout Code char bfr[ MAXBFRSIZE+1 ]; \end_layout \begin_layout Code int inBytes; \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Send a datagram to the server to wake it up. The content isn't \end_layout \begin_layout Code ** important, but something must be sent to let it know we want the TOD. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "write", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code write( sckt, "Are you there?", 14 ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code return; \end_layout \begin_layout Code } \end_layout \begin_layout Code /* \end_layout \begin_layout Code ** Read the time-of-day from the remote host. \end_layout \begin_layout Code */ \end_layout \begin_layout Code if ( !SYSCALL( "read", \end_layout \begin_layout Code __LINE__, \end_layout \begin_layout Code inBytes = read( sckt, \end_layout \begin_layout Code bfr, \end_layout \begin_layout Code MAXBFRSIZE ) ) ) \end_layout \begin_layout Code { \end_layout \begin_layout Code return; \end_layout \begin_layout Code } \end_layout \begin_layout Code bfr[ inBytes ] = ' \backslash 0'; /* Null-terminate the received string. */ \end_layout \begin_layout Code fputs( bfr, stdout ); /* Null string if EOF (inBytes == 0). */ \end_layout \begin_layout Code fflush( stdout ); \end_layout \begin_layout Code } /* End tod() */ \end_layout \begin_layout Section Other programming languages \end_layout \begin_layout Subsection JAVA \end_layout \begin_layout Standard Sun Java versions since 1.4 are IPv6 enabled, see e.g. \begin_inset CommandInset href LatexCommand href name "Inet6Address (1.5/5.0)" target "http://java.sun.com/j2se/1.5.0/docs/api/java/net/Inet6Address.html" \end_inset class. Hints are available in the \emph on Networking IPv6 User Guide for JDK/JRE \emph default \begin_inset CommandInset href LatexCommand href name "1.4" target "http://java.sun.com/j2se/1.4.2/docs/guide/net/ipv6_guide/index.html" \end_inset and \begin_inset CommandInset href LatexCommand href name "1.5 (5.0)" target "http://java.sun.com/j2se/1.5.0/docs/guide/net/ipv6_guide/index.html" \end_inset . \end_layout \begin_layout Subsection Perl \end_layout \begin_layout Standard As of May 2007 it's not known that the Perl core itself already supports IPv6. It can be added by using following modules: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Socket6" target "http://search.cpan.org/~umemoto/Socket6/" \end_inset \end_layout \begin_layout Standard Anyway, some other modules exist for/with IPv6 support (e.g. Net::IP), search for \begin_inset Quotes sld \end_inset IPv6 \begin_inset Quotes srd \end_inset on \begin_inset CommandInset href LatexCommand href name "http://search.cpan.org/" target "http://search.cpan.org/" \end_inset . \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-interoperability" \end_inset Interoperability \end_layout \begin_layout Standard The \begin_inset CommandInset href LatexCommand href name "TAHI Project" target "http://www.tahi.org/" \end_inset checks the interoperability of different operating systems regarding the implementation of IPv6 features. Linux kernel already got the \begin_inset CommandInset href LatexCommand href name "IPv6 Ready Logo Phase 1" target "http://www.linux-ipv6.org/v6ready/" \end_inset . \end_layout \begin_layout Chapter \begin_inset CommandInset label LatexCommand label name "chapter-information" \end_inset Further information and URLs \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-books" \end_inset Paper printed books, articles, online reviews (mixed) \end_layout \begin_layout Subsection Printed Books (English) \end_layout \begin_layout Subsubsection Cisco \end_layout \begin_layout Itemize Cisco Self-Study: Implementing IPv6 Networks (IPV6) by Regis Desmeules. Cisco Press; ISBN 1587050862; 500 pages; 1st edition (April 11, 2003). \begin_inset Newline newline \end_inset Note: This item will be published on April 11, 2003. \end_layout \begin_layout Itemize Configuring IPv6 with Cisco IOS by Sam Brown, Sam Browne, Neal Chen, Robbie Harrell, Edgar, Jr. Parenti (Editor), Eric Knipp (Editor), Paul Fong (Editor)362 pages; Syngress Media Inc; ISBN 1928994849; (July 12, 2002). \end_layout \begin_layout Subsubsection General \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "IPv6 in Practice: A Unixer's Guide to the Next Generation Internet" target "http://www.benedikt-stockebrand.de/books_e.html#ipv6-in-practice" \end_inset von Benedikt Stockebrand, November 2006; ISBN 3-540-24524-3 \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Essentials" target "http://www.sunny.ch/publications/f_ipv6.htm" \end_inset by Silvia Hagen, \lang ngerman 2nd Edition, May 2006; ISBN 0-5961-0058-2 \lang english \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "ToC, Index, Sample Chapter etc." target "http://www.oreilly.com/catalog/ipv6ess/" \end_inset ; \begin_inset CommandInset href LatexCommand href name "O'Reilly Pressrelease" target "http://press.oreilly.com/ipv6ess.html" \end_inset \end_layout \begin_layout Itemize IPv6: The New Internet Protocol. By Christian Huitema; Published by Prentice-Hall; ISBN 0138505055. \begin_inset Newline newline \end_inset Description: This book, written by Christian Huitema - a member of the InternetA rchitecture Board, gives an excellent description of IPv6, how it differs from IPv4, and the hows and whys of it's development. \begin_inset Newline newline \end_inset Source: \begin_inset CommandInset href LatexCommand href name "http://www.cs.uu.nl/wais/html/na-dir/internet/tcp-ip/resource-list.html" target "http://www.cs.uu.nl/wais/html/na-dir/internet/tcp-ip/resource-list.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Networks" target "http://www.epinions.com/book_mu-3402412/display_~full_specs" \end_inset by Niles, Kitty; (ISBN 0070248079); 550 pages; Date Published 05/01/1998. \end_layout \begin_layout Itemize Implementing IPV6. Supporting the Next Generation Internet Protocols by P. E. Miller, Mark A. Miller; Publisher: John Wiley & Sons; ISBN 0764545892; 2nd edition (March 15, 2000); 402 pages. \end_layout \begin_layout Itemize Big Book of Ipv6 Addressing Rfcs by Peter H. Salus (Compiler), Morgan Kaufmann Publishers, April 2000, 450 pages ISBN 0126167702. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Understanding IPV6" target "http://www.epinions.com/book_mu-3922588/display_~full_specs" \end_inset by Davies, Joseph; ISBN 0735612455; Date Published 05/01/2001; Number of Pages: 350. \end_layout \begin_layout Itemize Migrating to IPv6 - IPv6 in Practice by Marc Blanchet Publisher: John Wiley & Sons; ISBN 0471498920; 1st edition (November 2002); 368 pages. \end_layout \begin_layout Itemize Ipv6 Network Programming by Jun-ichiro Hagino; ISBN 1555583180 \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Wireless boosting IPv6" target "http://www.nwfusion.com/news/2000/1023ipv6.html" \end_inset by Carolyn Duffy Marsan, 10/23/2000. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "O'reilly Network search for keyword IPv6" target "http://www.oreillynet.com/search/index.ncsp?sp-q=IPv6" \end_inset results in 29 hits (28. January 2002) \end_layout \begin_layout Subsection Articles, eBooks, Online Reviews (mixed) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Getting Connected with 6to4" target "http://www.onlamp.com/pub/a/onlamp/2001/06/01/ipv6_tutorial.html" \end_inset by Huber Feyrer, 06/01/2001 \end_layout \begin_layout Itemize Transient Addressing for Related Processes: Improved Firewalling by Using IPv6 and Multiple Addresses per Host; written by Peter M. Gleiz, Steven M. Bellovin ( \begin_inset CommandInset href LatexCommand href name "PC-PDF-Version" target "http://www.securiteinfo.com/ebooks/pdf/tarp.pdf" \end_inset ; \begin_inset CommandInset href LatexCommand href name "Palm-PDF-Version" target "http://www.securiteinfo.com/ebooks/palm/tarp.pdf" \end_inset ; \begin_inset CommandInset href LatexCommand href name "PDB-Version" target "http://www.securiteinfo.com/ebooks/pdb/tarp.pdb" \end_inset ) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Internetworking IPv6 with Cisco Routers" target "http://www.ip6.com/index.html" \end_inset by Silvano Gai, McGrawHill Italia, 1997. The 13 chapters and appendix A-D are downloadable as PDF-documents. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Migration and Co-existence of IPv4 and IPv6 in Residential Networks" target "http://www.csc.fi/~psavola/residential.html" \end_inset by Pekka Savola, CSC/FUNET, 2002 \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "information-sciencepublication" \end_inset Science Publications (abstracts, bibliographies, online resources) \end_layout \begin_layout Standard See also: \begin_inset CommandInset href LatexCommand href name "liinwww.ira.uka.de/ipv6" target "http://liinwww.ira.uka.de/mpsbib?query=ipv6&maxnum=200" \end_inset or \begin_inset CommandInset href LatexCommand href name "Google / Scholar / IPv6" target "http://www.google.com/scholar?q=ipv6" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "GEANT IPv6 Workplan" target "http://www.ipv6.ac.uk/gtpv6/workplan.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Trials on UK Academic Networks: Bermuda Project Aug.2002" target "http://www.ipv6.ac.uk/bermuda2/" \end_inset : Participants - Getting connected - Project deliverables - Network topology - Address assignments - Wireless IPv6 access - IPv6 migration - Project presentations - Internet 2 - Other IPv6 projects - IPv6 fora and standards Bermuda 2... \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "http://www.ipv6.ac.uk/" target "http://www.ipv6.ac.uk/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 at the University of Southampton" target "http://www.ipv6.ecs.soton.ac.uk/" \end_inset \end_layout \begin_layout Itemize Microsoft Research IPv6 Implementation (MSRIPv6): \begin_inset CommandInset href LatexCommand href name "MSRIPv6 Configuring 6to4 - Connectivity with MSR IPv6 - Our 6Bone Node... " target "http://www.research.microsoft.com/msripv6/" \end_inset \end_layout \begin_layout Subsection Others \end_layout \begin_layout Standard See following URL for more: \begin_inset CommandInset href LatexCommand href name "SWITCH IPv6 Pilot / References" target "http://www.switch.ch/lan/ipv6/references.html" \end_inset \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-conferences" \end_inset Conferences, Meetings, Summits \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsection 2004 \end_layout \begin_layout Itemize 1st Global IPv6 Summit in Sao Paul, Brazil \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-onlineinformation" \end_inset Online information \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "information-joinipv6" \end_inset Join the IPv6 backbone \end_layout \begin_layout Standard More to be filled later...suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-globalregistries" \end_inset Global registries \end_layout \begin_layout Standard See regional registries. \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-majorregionregistries" \end_inset Major regional registries \end_layout \begin_layout Itemize America: \begin_inset CommandInset href LatexCommand href name "ARIN" target "http://www.arin.net/" \end_inset , \begin_inset CommandInset href LatexCommand href name "ARIN / registration page" target "http://www.arin.net/registration/ipv6/index.html" \end_inset , \lang ngerman \begin_inset CommandInset href LatexCommand href name "ARIN / IPv6 guidelines" target "http://www.arin.net/registration/ipv6/index.html" \end_inset \end_layout \begin_layout Itemize EMEA: \begin_inset CommandInset href LatexCommand href name "Ripe NCC" target "http://www.ripe.net/" \end_inset , \begin_inset CommandInset href LatexCommand href name "Ripe NCC / registration page" target "http://www.ripe.net/ripencc/mem-services/registration/" \end_inset , \begin_inset CommandInset href LatexCommand href name "Ripe NCC / IPv6 registration" target "http://www.ripe.net/ripencc/mem-services/registration/ipv6/" \end_inset \end_layout \begin_layout Itemize Asia/Pacific: \begin_inset CommandInset href LatexCommand href name "APNIC" target "http://www.apnic.net/" \end_inset , \begin_inset CommandInset href LatexCommand href name "APNIC / IPv6 ressource guide" target "http://www.apnic.net/services/ipv6_guide.html" \end_inset \end_layout \begin_layout Itemize Latin America and Caribbea: \begin_inset CommandInset href LatexCommand href name "LACNIC" target "http://lacnic.org/" \end_inset , \begin_inset CommandInset href LatexCommand href name "IPv6 Registration Services" target "http://lacnic.net/en/bt-IPv6.html" \end_inset , \begin_inset CommandInset href LatexCommand href name "IPv6 Allocation Policy" target "http://lacnic.net/en/chapter-4-en.pdf" \end_inset \end_layout \begin_layout Itemize Africa: \begin_inset CommandInset href LatexCommand href name "AfriNIC" target "http://www.afrinic.org/" \end_inset \end_layout \begin_layout Standard Also a list of major (prefix length 32) allocations per local registry is available here: \begin_inset CommandInset href LatexCommand href name "Ripe NCC / IPv6 allocations" target "http://www.ripe.net/ripencc/mem-services/registration/ipv6/ipv6allocs.html" \end_inset . \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-joinipv6-tunnelbrokers" \end_inset Tunnel brokers \end_layout \begin_layout Standard Note: A list of available Tunnel broker can be found in the section \begin_inset CommandInset ref LatexCommand ref name "Tunnel broker" reference "information-Tunnelbroker" \end_inset below. \end_layout \begin_layout Itemize Former IPng. Tunnelbroker and IPv6 resources, now migrated to the \begin_inset CommandInset href LatexCommand href name "SixXs System" target "http://www.sixxs.net/main/" \end_inset . \end_layout \begin_layout Itemize Eckes' \begin_inset CommandInset href LatexCommand href name "IPv6-with-Linux" target "http://sites.inka.de/lina/linux/ipv6.html" \end_inset Page. \end_layout \begin_layout Itemize tunnelc - a perl based tunnel client script: \begin_inset Newline newline \end_inset freshmeat.net: \begin_inset CommandInset href LatexCommand href name "Project details for tunnel client" target "http://freshmeat.net/projects/tunnelc" \end_inset \begin_inset Newline newline \end_inset SourceForge: \begin_inset CommandInset href LatexCommand href name "Project Info - tunnelc" target "http://sourceforge.net/projects/tunnelc" \end_inset (also \begin_inset CommandInset href LatexCommand href name "here" target "http://tunnelc.sourceforge.net/" \end_inset ) \end_layout \begin_layout Itemize Linux Advanced Routing & Traffic Control HOWTO, \begin_inset CommandInset href LatexCommand href name "Chapter 6: IPv6 tunneling with Cisco and/or 6bone" target "http://howtos.linuxbroker.com/howtoreader.shtml?file=Adv-Routing-HOWTO.html#LARTC.TUNNEL-IPV6.ADDRESSING" \end_inset . \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-joinipv6-6to4-tunneling" \end_inset 6to4 \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NSayer's 6to4 information" target "http://www.kfu.com/~nsayer/6to4/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "RFC 3068 / An Anycast Prefix for 6to4 Relay Routers" target "http://www.faqs.org/rfcs/rfc3068.html" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-joinipv6-isatap-tunneling" \end_inset ISATAP \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ISATAP (Intra-Site Automatic Tunnel Access Protocol) Information" target "http://www.join.uni-muenster.de/Dokumente/Howtos/Howto_ISATAP.php?lang=en" \end_inset by \begin_inset CommandInset href LatexCommand href name "JOIN" target "http://www.join.uni-muenster.de/" \end_inset \end_layout \begin_layout Subsection Latest news and URLs to other documents \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Lot of URLs to others documents" target "http://www.estoile.com/links/ipv6" \end_inset by Anil Edathara \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "go6 - The IPv6 Portal" target "http://www.go6.net/" \end_inset : an IPv6 online portal with a wiki-based IPv6 knowledge center, an IPv6 discussion forum, an up-to-date collection of IPv6 Events and News, free IPv6 access and services, IPv6 software applications, and much more \end_layout \begin_layout Subsection Protocol references \end_layout \begin_layout Subsubsection IPv6-related Request For Comments (RFCs) \end_layout \begin_layout Standard Publishing the list of IPv6-related RFCs is beyond the scope of this document, but given URLs will lead you to such lists: \end_layout \begin_layout Itemize List sorted by \begin_inset CommandInset href LatexCommand href name "IPng Standardization Status" target "http://playground.sun.com/pub/ipng/html/specs/standards.html" \end_inset or \begin_inset CommandInset href LatexCommand href name "IPng Current Specifications" target "http://playground.sun.com/pub/ipng/html/specs/specifications.html" \end_inset by Robert Hinden \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Related Specifications" target "http://www.ipv6.org/specs.html" \end_inset on IPv6.org \end_layout \begin_layout Subsubsection Current drafts of working groups \end_layout \begin_layout Standard Current (also) IPv6-related drafts can be found here: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IP Version 6 (ipv6)" target "http://www.ietf.org/ids.by.wg/ipv6.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Next Generation Transition (ngtrans)" target "http://www.ietf.org/ids.by.wg/ngtrans.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Dynamic Host Configuration (dhc)" target "http://www.ietf.org/ids.by.wg/dhc.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Domain Name System Extension (dnsext)" target "http://www.ietf.org/ids.by.wg/dnsext.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Operations (v6ops)" target "http://www.ietf.org/ids.by.wg/v6ops.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Mobile IP (mobileip)" target "http://www.ietf.org/ids.by.wg/mobileip.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Get any information about IPv6, from overviews, through RFCs & drafts, to implementations" target "http://playground.sun.com/pub/ipng/html/ipng-main.html" \end_inset (including availability of stacks on various platforms & source code for IPv6 stacks) \end_layout \begin_layout Subsubsection Others \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SWITCH IPv6 Pilot / References" target "http://www.switch.ch/lan/ipv6/references.html" \end_inset , big list of IPv6 references maintained by Simon Leinen \end_layout \begin_layout Subsection More information \end_layout \begin_layout Standard \lang ngerman \begin_inset CommandInset href LatexCommand href name "DeepSpace6 / more interesting links" target "http://www.deepspace6.net/sections/links.html" \end_inset \end_layout \begin_layout Subsubsection Linux related \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DeepSpace6 / (Not only) Linux IPv6 Portal" target "http://www.deepspace6.net/" \end_inset - Italy ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/" \end_inset ) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6-HowTo for Linux by Peter Bieringer" target "http://www.bieringer.de/linux/IPv6/" \end_inset - Germany, and his \begin_inset CommandInset href LatexCommand href name "Bieringer / IPv6 - software archive" target "ftp://ftp.bieringer.de/pub/linux/IPv6/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Linux+IPv6 status by Peter Bieringer" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status.html" \end_inset - Germany (going obsolete) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DeepSpace6 / IPv6 Status Page" target "http://www.deepspace6.net/docs/ipv6_status_page_apps.html" \end_inset - Italy ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/docs/ipv6_status_page_apps.html" \end_inset ) (will superseed upper one) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "USAGI project" target "http://www.linux-ipv6.org/" \end_inset - Japan, and their \begin_inset CommandInset href LatexCommand href name "USAGI project - software archive" target "ftp://ftp.linux-ipv6.org/pub/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Linux Optimized Link State Routing Protocol (OLSR) IPv6 HOWTO" target "http://www.tldp.org/HOWTO/OLSR-IPv6-HOWTO/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "LinShim6" target "http://inl.info.ucl.ac.be/LinShim6/" \end_inset \end_layout \begin_layout Subsubsection Linux related per distribution \end_layout \begin_layout Description PLD \begin_inset CommandInset href LatexCommand href name "PLD Linux Distribution" target "http://www.pld-linux.org/" \end_inset ( \begin_inset Quotes sld \end_inset market leader \begin_inset Quotes srd \end_inset in containing IPv6 enabled packages) \end_layout \begin_layout Description Red \begin_inset space ~ \end_inset Hat \begin_inset CommandInset href LatexCommand href name "Red Hat Enterprise Linux" target "http://www.redhat.com/" \end_inset , \begin_inset CommandInset href LatexCommand href name " Pekka Savola's IPv6 packages (Historic)" target "http://www.netcore.fi/pekkas/linux/ipv6/" \end_inset \end_layout \begin_layout Description \lang ngerman Fedora \begin_inset CommandInset href LatexCommand href name "Fedora (Project) Linux" target "https://fedoraproject.org/" \end_inset \end_layout \begin_layout Description Debian \begin_inset CommandInset href LatexCommand href name "Debian Linux" target "http://www.debian.org/" \end_inset , \lang ngerman \begin_inset CommandInset href LatexCommand href name "IPv6 with Debian Linux" target "http://ipv6.debian.net/" \end_inset \end_layout \begin_layout Description \lang ngerman SuSE \begin_inset CommandInset href LatexCommand href name "SuSE Linux" target "https://www.suse.com/" \end_inset \end_layout \begin_layout Description Mandriva \begin_inset CommandInset href LatexCommand href name "Mandriva (Historic)" target "http://wiht.link/mandrivalinux" \end_inset \end_layout \begin_layout Standard For more see the \begin_inset CommandInset href LatexCommand href name "IPv6+Linux Status Distributions" target "http://www.bieringer.de/linux/IPv6/status/IPv6+Linux-status-distributions.html" \end_inset page. \end_layout \begin_layout Subsubsection General \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6.org" target "http://www.ipv6.org/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6bone" target "http://www.6bone.net/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "WIDE project" target "http://www.v6.wide.ad.jp/" \end_inset - Japan \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SWITCH IPv6 Pilot" target "http://www.switch.ch/lan/ipv6/" \end_inset - Switzerland \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Corner of Hubert Feyrer" target "http://www.feyrer.de/IPv6/" \end_inset - Germany \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Forum" target "http://www.ipv6forum.com/" \end_inset - a world-wide consortium of leading Internet vendors, Research & Education Networks... \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Playground.sun.com / IPv6 Info Page" target "http://playground.sun.com/pub/ipng/html/ipng-main.html" \end_inset - maintained by Robert Hinden, Nokia. Get any information about IPv6, from overviews, through RFCs & drafts, to implementations (including availability of stacks on various platforms & source code for IPv6 stacks). \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6INIT" target "http://www.6init.com/" \end_inset - IPv6 Internet Initiative - an EU Fifth Framework Project under the IST Programme. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Task Force (European Union)" target "http://www.ipv6-taskforce.org/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6init" target "http://www.6init.org/" \end_inset - IPv6 INternet IniTiative \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6: The New Version of the Internet Protocol" target "http://www.usenix.org/publications/library/proceedings/ana97/summaries/deering.html" \end_inset , by Steve Deering. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6: The Next Generation Internet Protocol" target "http://www.garykessler.net/library/ipv6_exp.html" \end_inset , by Gary C. Kessler. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6: Next Generation Internet Protocol" target "http://www.3com.com/nsc/ipv6.html" \end_inset - 3Com \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "internet || site" target "http://www.internet2.org/" \end_inset and \begin_inset CommandInset href LatexCommand href name "internet2 Working Group" target "http://ipv6.internet2.edu/" \end_inset \end_layout \begin_layout Itemize NetworkWorldFusion: Search / Doc Finder: \begin_inset CommandInset href LatexCommand href name "searched for IPv6" target "http://search.nwfusion.com/query.html?qt=IPv6&qp=&ch=cn&" \end_inset (102 documents found 22.12.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "The Register" target "http://www.theregister.co.uk/" \end_inset (Search for IPv6 will result in 30 documents, 22.12.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ZDNet Search for IPv6" target "http://zdnet.search.com/search?cat=279&q=IPv6" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "TechTarget Search for IPv6" target "http://whatis.techtarget.com/wsearchResults/1,290214,sid9,00.html?query=IPv6" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 & TCP Resources List" target "http://www.faqs.org/faqs/internet/tcp-ip/resource-list/index.html" \end_inset \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-marketresearch" \end_inset Market Research \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "statista - The Statistics Portal" target "http://www.statista.com/search/internet+america/" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "Market Research" target "http://www.marketresearch.com/" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-patents" \end_inset Patents \end_layout \begin_layout Itemize Delphion Research: \begin_inset CommandInset href LatexCommand href name "Patent Search Page" target "http://www.delphion.com/research/" \end_inset . Basic (free) registration needed. Examples found 21.12.2002 searching for IPv6: \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Communicating method between IPv4 terminal and IPv6 terminal and IPv4-IPv6 converting apparatus" target "http://www.delphion.com/details?pn=US06118784__" \end_inset \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Translator for IP networks, network system using the translator, and IP network coupling method therefor" target "http://www.delphion.com/details?pn=US06038233__" \end_inset \end_layout \begin_layout Subsection By countries \end_layout \begin_layout Subsubsection Europe \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "www.ist-ipv6.org" target "http://www.ist-ipv6.org/" \end_inset : IST IPv6 Cluster, European IPv6 Research and Development Projects \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Euro6IX" target "http://www.euro6ix.org/" \end_inset : European IPv6 Internet Exchanges Backbone \end_layout \begin_layout Subsubsection Austria \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6@IKNnet and MIPv6 Research Group" target "http://www.ikn.tuwien.ac.at/~ipv6/" \end_inset : TU Vienna, Austria (IPv6: project, publications, diploma / doctor thesis, Conference Proceedings etc.) \end_layout \begin_layout Subsubsection Australia \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Carl's Australian IPv6 Pages" target "http://oversteer.bl.echidna.id.au/IPv6/" \end_inset (old content) \end_layout \begin_layout Subsubsection Belgium \end_layout \begin_layout Standard Suggestions are welcome! \end_layout \begin_layout Subsubsection Brasil \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 do Brasil" target "http://www.ipv6dobrasil.com.br/" \end_inset \end_layout \begin_layout Subsubsection China \end_layout \begin_layout Standard Suggestions are welcome! \end_layout \begin_layout Subsubsection Czech \end_layout \begin_layout Standard Suggestions are welcome! \end_layout \begin_layout Subsubsection Germany \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Xing / IPv6" target "https://www.xing.com/net/ipv6/" \end_inset \end_layout \begin_layout Subsubsection France \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Renater" target "http://www.renater.fr/Projets/IPv6/index.htm" \end_inset : Renater IPv6 Project Page \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 - RSVP - ATM at INRIA" target "http://www.inria.fr/recherche/equipes/ipv6.fr.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NetBSD IPv6 Documentation" target "http://www.netbsd.org/fr/Documentation/network/ipv6/" \end_inset \end_layout \begin_layout Subsubsection Italy \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Project6" target "http://project6.ferrara.linux.it/" \end_inset : IPv6 networking with Linux \end_layout \begin_layout Subsubsection Japan \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Yamaha IPv6" target "http://www.rtpro.yamaha.co.jp/RT/ipv6/" \end_inset (sorry, all in japanese native ...) \end_layout \begin_layout Subsubsection Korea \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ETRI" target "http://www.krv6.net/" \end_inset : Electronics and Telecommunications Research Institut \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Forum Korea" target "http://www.ipv6.or.kr/english/index.new.htm" \end_inset : Korean IPv6 Deployment Project \end_layout \begin_layout Subsubsection Mexico \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Mexico" target "http://www.ipv6.unam.mx/" \end_inset (spain & english version): IPv6 Project Hompeage of The National Autonomous University of Mexico (UNAM) \end_layout \begin_layout Subsubsection Netherland \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SURFnet" target "http://www.ipv6.surfnet.nl/" \end_inset : SURFnet IPv6 Backbone \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "STACK" target "http://www.stack.nl/" \end_inset , \begin_inset CommandInset href LatexCommand href name "STACK (IPv6)" target "http://www.stack.nl/ipv6/" \end_inset : Students' computer association of the Eindhoven University of Technology, Netherland \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPng.nl" target "http://www.ipng.nl/" \end_inset : collaboration between WiseGuys and Intouch \end_layout \begin_layout Subsubsection Portugal \end_layout \begin_layout Standard Suggestions are welcome! \end_layout \begin_layout Subsubsection Russia \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Forum for Russia" target "http://www.ipv6.ru/" \end_inset : Yaroslavl State University Internet Center \end_layout \begin_layout Subsubsection Switzerland \end_layout \begin_layout Standard Suggestions are welcome! \end_layout \begin_layout Subsubsection United Kingdom \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "British Telecom IPv6 Home" target "http://www.bt.com/ipv6/" \end_inset : BT's ISP IPv6 Trial, UK's first IPv6 Internet Exchange etc. \end_layout \begin_layout Subsection By operating systems \end_layout \begin_layout Subsubsection *BSD \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "KAME project" target "http://www.kame.net/" \end_inset (*BSD) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NetBSD's IPv6 Networking FAQ" target "http://www.netbsd.org/Documentation/network/ipv6/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "FreeBSD Ports: Ipv6" target "http://www.freebsd.org/ports/ipv6.html" \end_inset \end_layout \begin_layout Subsubsection Cisco IOS \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Cisco IOS IPv6 Entry Page" target "http://www.cisco.com/warp/public/732/Tech/ipv6/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 for Cisco IOS Software" target "http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t2/ipv6/ftipv6c.htm" \end_inset , File 2 of 3: Aug 2002 -- Table of Contents: IPv6 for Cisco IOS Software; Configuring Documentation Specifics; Enabling IPv6 Routing and Configuring; IPv6 Addressing; Enabling IPv6 Processing Globally. \end_layout \begin_layout Itemize Cisco Internet Networking Handbook, \begin_inset CommandInset href LatexCommand href name "Chapter IPv6" target "http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/ipv6.htm" \end_inset \end_layout \begin_layout Subsubsection HPUX \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "comp.sys.hp.hpux FAQ" target "http://www.faqs.org/faqs/hp/hpux-faq/index.html" \end_inset \end_layout \begin_layout Subsubsection IBM \end_layout \begin_layout Itemize Now that IBM's announced the availability of z/OS V1.4, \begin_inset CommandInset href LatexCommand href name "what's new in this release?" target "http://search390.techtarget.com/ateQuestionNResponse/0,289625,sid10_cid486367_tax292523,00.html" \end_inset This question was posed on 15 August 2002 \end_layout \begin_layout Subsubsection Microsoft \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Microsoft Windows 2000 IPv6" target "http://www.microsoft.com/windows2000/technologies/communications/ipv6/default.asp" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "MSRIPv6" target "http://www.research.microsoft.com/msripv6" \end_inset - Microsoft Research Network - IPv6 Homepage \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Internet Connection Firewall Does Not Block Internet Protocol Version 6 Traffic" target "http://support.microsoft.com/default.aspx?scid=kb;en-us;306203" \end_inset (6.11.2001) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Internet Protocol Numbers" target "http://support.microsoft.com/default.aspx?scid=kb;en-us;289892" \end_inset (8.10.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Technology Preview Refresh" target "http://support.microsoft.com/default.aspx?scid=kb;en-us;273826" \end_inset (16.10.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "HOW TO: Install and Configure IP Version 6 in Windows .NET Enterprise Server" target "http://support.microsoft.com/default.aspx?scid=kb;en-us;325449" \end_inset (26.10.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Windows .NET Server 6to4 Router Service Quits When You Advertise a 2002 Address on the Public Interface" target "http://support.microsoft.com/default.aspx?scid=kb;en-us;329984" \end_inset (28.10.2002) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "msdn - Microsoft Windows CE .NET - IPv6 commands" target "http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wcetcpip/htm/cmconIPv6exe.asp" \end_inset \end_layout \begin_layout Subsubsection Solaris \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Sun Microsystems Solaris" target "http://www.sun.com/software/solaris/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Solaris 2 Frequently Asked Questions (FAQ) 1.73" target "http://www.cs.uu.nl/wais/html/na-dir/Solaris2/FAQ.html" \end_inset \end_layout \begin_layout Subsubsection Sumitoma \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Sumitomo Electric has implemented IPv6 on Suminet 3700 family routers" target "http://playground.sun.com/pub/ipng/html/ipng-implementations.html#Sumitomo" \end_inset \end_layout \begin_layout Subsubsection ZebOS \end_layout \begin_layout Itemize IpInfusion's \begin_inset CommandInset href LatexCommand href name "ZebOS Server Routing Software" target "http://www.ipinfusion.com/products/server/products_server.html" \end_inset \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "information-ipv6andsecurity" \end_inset IPv6 Security \end_layout \begin_layout Itemize Internet Security Systems: Security Center, \begin_inset CommandInset href LatexCommand href name "X-Force Database Search" target "http://www.iss.net/security_center/search.php?type=3&type=3&pattern=IPv6" \end_inset (21.12.2002 - 6 topics found relating to IPv6) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NIST IPsec Project" target "http://csrc.nist.gov/ipsec/" \end_inset ( National Institute of Standards and Technology, NIST) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Information Security" target "http://www.infosecuritymag.com/index.shtml" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NewOrder.box.sk (search for IPv6)" target "http://neworder.box.sk/search.php3?srch=IPv6" \end_inset (Articles, exploits, files database etc.) \end_layout \begin_layout Subsection Application lists \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DeepSpace6 / IPv6 Status Page" target "http://www.deepspace6.net/docs/ipv6_status_page_apps.html" \end_inset ( \begin_inset CommandInset href LatexCommand href name "Mirror" target "http://mirrors.bieringer.de/www.deepspace6.net/docs/ipv6_status_page_apps.html" \end_inset ) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6.org / IPv6 enabled applications" target "http://www.ipv6.org/v6-apps.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Freshmeat / IPv6 search" target "http://freshmeat.net/search/?q=IPv6" \end_inset , currently (14 Dec 2002) 62 projects \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Forum / Web Links" target "http://www.ipv6forum.com/modules.php?op=modload&name=Web_Links&file=index" \end_inset \end_layout \begin_layout Subsubsection Analyzer tools \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Wireshark" target "http://www.wireshark.org/" \end_inset (former known as \emph on Ethereal \emph default ) is a free network protocol analyzer for Unix and Windows \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Radcom RC100-WL" target "http://www.ip6.com/us/analyzer.htm" \end_inset - Download Radcom RC100-WL protocol analyzer version 3.20 \end_layout \begin_layout Subsubsection IPv6 Products \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6wind" target "http://www.6wind.com/" \end_inset - solutions for IPv4/IPv6 Router, QoS, Multicast, Mobility, Security/VPN/Firewa ll. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Fefe's patches for IPv6 with djbdns" target "http://www.fefe.de/dns/" \end_inset Aug 2002 -- What is djbdns and why does it need IPv6? djbdns is a full blown DNS server which outperforms BIND in nearly all respects. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ZebOS Server Routing Suite " target "http://www.ipinfusion.com/products/server/products_server.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Inframail (Advantage Server Edition)" target "http://download.cnet.com/Inframail-Advantage-Server-Edition/3000-10248_4-8202652.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "HTTrack Website Copier" target "http://download.cnet.com/HTTrack-Website-Copier/3000-2377_4-10149393.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "CommView" target "http://download.cnet.com/CommView/3000-2085_4-10132748.html" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Posadis" target "http://download.cnet.com/Posadis/3000-2155_4-10149750.html" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-snmp" \end_inset SNMP \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "comp.protocpols.snmp SNMP FAQ Part 1 of 2" target "http://www.cs.uu.nl/wais/html/na-dir/snmp-faq/part1.html" \end_inset \end_layout \begin_layout Section IPv6 Infrastructure \end_layout \begin_layout Subsection Statistics \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 routing table history" target "http://www.space.net/~gert/RIPE/" \end_inset created by Gert Döring, \begin_inset CommandInset href LatexCommand href name "Space.Net" target "http://www.space.net/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Official 6bone Webserver list Statisic" target "http://6bone.informatik.uni-leipzig.de/ipv6/stats/stats.php3" \end_inset \end_layout \begin_layout Subsection Internet Exchanges \end_layout \begin_layout Standard Another list of IPv6 Internet Exchanges can be found here: \begin_inset CommandInset href LatexCommand href name "IPv6 status of IXPs in Europe" target "http://www.euro-ix.net/isp/choosing/search/matrix.php" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-estonia" \end_inset Estonia \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "TIX" target "http://tix.estpak.ee/" \end_inset (tallinn interneti exchange with ipv6 support) \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-europe" \end_inset Europe \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Euro6IX" target "http://www.euro6ix.net/" \end_inset , European IPv6 Internet Exchange Backbone \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-france" \end_inset France \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "French National Internet Exchange IPv6" target "http://www.fnix6.net/" \end_inset (since 1.11.2002 active). \begin_inset Newline newline \end_inset FNIX6 provides a free and reliable high speed FastEthernet interconnection between ISP located in TeleCity Paris. \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-germany" \end_inset Germany \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "INXS" target "http://www.inxs.de/" \end_inset : (Cable & Wireless) Munich and Hamburg \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-japan" \end_inset Japan \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NSPIXP-6" target "http://www.wide.ad.jp/nspixp6/" \end_inset : IPv6-based Internet Exchange in Tokyo \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "JPIX" target "http://www.jpix.co.jp/" \end_inset , Tokyo \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-korea" \end_inset Korea \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6NGIX" target "http://www.ngix.ne.kr/" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-netherlands" \end_inset Netherlands \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "AMS-IX" target "http://www.ams-ix.net/" \end_inset \lang english : Amsterdam Internet Exchange \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-uk" \end_inset UK \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "UK6X" target "http://www.uk6x.com/" \end_inset : London \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "XchangePoint" target "http://www.xchangepoint.net/" \end_inset : London \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-ipv6exchanges-usa" \end_inset USA \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6TAP" target "http://www.6tap.net/" \end_inset : Chicago. Supports peerings around the globe. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "PAIX" target "http://www.paix.net/" \end_inset : Palo Alto \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "information-Tunnelbroker" \end_inset Tunnel broker \end_layout \begin_layout Standard See also: \begin_inset CommandInset href LatexCommand href name "http://www.deepspace6.net/docs/tunnelbrokers.html" target "http://www.deepspace6.net/docs/tunnelbrokers.html" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-belgium" \end_inset Belgium \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-canada" \end_inset Canada \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Freenet6" target "http://www.freenet6.net/" \end_inset - /48 Delegation, Canada \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Getting IPv6 Using Freenet6 on Debian" target "http://www.linuxjournal.com/article.php?sid=5963&mode=thread&order=0" \end_inset \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Freenet6 creater" target "http://www.viagenie.qc.ca/en/index.shtml" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-china" \end_inset China \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-estonia" \end_inset Estonia \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Estpak" target "http://tunnelbroker.ipv6.estpak.ee/?tunnel&PHPSESSID=aa2184190cc2cc6d3a6f6ddd01ae3635" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-germany" \end_inset Germany \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "6bone Knoten Leipzig" target "http://6bone.informatik.uni-leipzig.de/" \end_inset \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Info bez. Hackangriff (2001)" target "http://www.mail-archive.com/ipv6@uni-muenster.de/msg00056.html" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-italy" \end_inset Italy \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Comv6" target "http://www.comv6.com/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Bersafe" target "http://www.bersafe.it/" \end_inset (Italian language) \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-japan" \end_inset Japan \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-malaysia" \end_inset Malaysia \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-netherlands" \end_inset Netherlands \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPng Netherland" target "http://www.ipng.nl/" \end_inset - Intouch, SurfNet, AMS-IX, UUNet, Cistron, RIPE NCC and AT&T are connected at the AMS-IX. It is possible (there are requirements...) to get an static tunnel. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "SURFnet Customers" target "http://www.ipv6.surfnet.nl/" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-norway" \end_inset Norway \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "UNINETT" target "http://www.uninett.no/testnett/index.en.html" \end_inset - Pilot IPv6 Service (for Customers): tunnelbroker & address allocation \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Uninett-Autoupdate-HOWTO" target "http://www.guruz.de/Uninett-Autoupdate-HOWTO" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-spain" \end_inset Spain \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Consulintel" target "http://tb.consulintel.euro6ix.org/" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-switzerland" \end_inset Switzerland \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-uk" \end_inset UK \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "NTT" target "http://www.nttv6.net/" \end_inset , United Kingdom - IPv6 Trial. IPv4 Tunnel and native IPv6 leased Line connections. POPs are located in London, UK Dusseldorf, Germany New Jersey, USA (East Coast) Cupertino, USA (West Coast) Tokyo, Japan \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-usa" \end_inset USA \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "ESnet" target "http://www.es.net/hypertext/welcome/pr/ipv6.html" \end_inset , USA - Energy Sciences Network: Tunnel Registry & Address Delegation for directly connected ESnet sites and ESnet collaborators. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Hurricane Electric" target "http://ipv6tb.he.net/" \end_inset , US backbone; \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Hurrican Electric Tunnelbroker" target "http://tunnelbroker.net/" \end_inset (also available under \begin_inset CommandInset href LatexCommand href name "http://tunnelbroker.com/" target "http://tunnelbroker.com/" \end_inset ) \begin_inset Newline newline \end_inset Press Release: \begin_inset CommandInset href LatexCommand href name "Hurricane Electric Upgrades IPv6 Tunnel Broker" target "http://www.he.net/releases/release6.html" \end_inset \begin_inset Newline newline \end_inset \begin_inset CommandInset href LatexCommand href name "Tunnel Broker Endpoint Autoupdate" target "http://ipv6.he.net/tunnelbroker-update.php" \end_inset , Perl Script \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-singapore" \end_inset Singapore \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-tunnelbroker-more" \end_inset More Tunnel brokers... \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Public 6to4 relay routers" target "http://www.kfu.com/~nsayer/6to4/" \end_inset (MS IIE boycott!) \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "information-infrastructure-nativeipv6service" \end_inset Native IPv6 Services \end_layout \begin_layout Standard Note: These services are mostly only available with a valid IPv6 connection! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-nativeipv6nntp" \end_inset Net News (NNTP) \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-nativeipv6gameserver" \end_inset Game Server \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Quake2" target "http://www.viagenie.qc.ca/en/ipv6/quake2/ipv6-quake2.shtml" \end_inset over IPv6 \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-nativeipv6ircserver" \end_inset IRC Server \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection Radio Stations, Music Streams \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "information-nativeipv6webserver" \end_inset Webserver \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Peter Bieringer's Home of Linux IPv6 HOWTO " target "http://www.ipv6.bieringer.de/" \end_inset \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-maillists" \end_inset Maillists \end_layout \begin_layout Standard Lists of maillists are available at: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DeepSpace6 / Mailling Lists" target "http://www.deepspace6.net/sections/lists.html" \end_inset \end_layout \begin_layout Standard Major Mailinglists are listed in following table: \end_layout \begin_layout Standard \begin_inset Tabular \begin_inset Text \begin_layout Plain Layout Focus \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Request e-mail address \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout What to subscribe \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Maillist e-mail address \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Language \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Access through WWW \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Linux kernel networking including IPv6 \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout majordomo (at) vger.kernel.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout netdev \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout netdev (at) vger.kernel.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info" target "http://vger.kernel.org/vger-lists.html#netdev" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://www.spinics.net/lists/netdev/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Mobile IP(v6) for Linux \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Web-based, see URL \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout mipl \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout mipl (at) mobile-ipv6.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info" target "http://www.mobile-ipv6.org/cgi-bin/mailman/listinfo" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://www.mobile-ipv6.org/pipermail/mipl/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Linux IPv6 users using USAGI extension \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout usagi-users-ctl (at) linux-ipv6.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout usagi-users (at) linux-ipv6.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info / Search" target "http://www.linux-ipv6.org/ml/index.html#usagi-users" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://www.linux-ipv6.org/ml/usagi-users/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout IPv6 on Debian Linux \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout debian-ipv6 (at) lists.debian.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info/Subscription/Archive" target "http://lists.debian.org/debian-ipv6/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout 6bone \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout majordomo (at) isi.edu \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout 6bone \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout 6bone (at) isi.edu \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info" target "http://www.6bone.net/6bone_email.html" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://mailman.isi.edu/pipermail/6bone/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout IPv6 users in general \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout majordomo (at) ipv6.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout users \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout users (at) ipv6.org \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info" target "http://www.ipv6.org/mailing-lists.html" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://www.mail-archive.com/users@ipv6.org/" \end_inset \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout Bugtracking of Internet applications (1) \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout bugtraq-subscribe (at) securityfocus.com \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout bugtraq (at) securityfocus.com (2) \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout English \end_layout \end_inset \begin_inset Text \begin_layout Plain Layout \begin_inset CommandInset href LatexCommand href name "Info" target "http://online.securityfocus.com/popups/forums/bugtraq/intro.shtml" \end_inset , \begin_inset CommandInset href LatexCommand href name "Archive" target "http://online.securityfocus.com/archive/1" \end_inset \end_layout \end_inset \end_inset \end_layout \begin_layout Standard (1) very recommended if you provide server applications. \end_layout \begin_layout Standard \lang ngerman (2) list is moderated. \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard Following other maillinglists & newsgroups are available via web: \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "student-ipv6 (India)" target "http://groups.yahoo.com/group/student-ipv6" \end_inset \begin_inset Newline newline \end_inset Description: This is the group for the Student Awareness group of IPv6 in India \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "sun-ipv6-users" target "http://groups.yahoo.com/group/sun-ipv6-users" \end_inset \begin_inset Newline newline \end_inset Description: Please report problems/suggestions regarding SUN Microsystems IPng implementation \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6-BITS" target "http://groups.yahoo.com/group/IPv6-BITS" \end_inset \begin_inset Newline newline \end_inset Description: This List will co-ordinate the working of Project Vertebrae. \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "linux-bangalore-ipv6" target "http://groups.yahoo.com/group/linux-bangalore-ipv6" \end_inset \begin_inset Newline newline \end_inset Description: The IPv6 deployment list of the Bangalore Linux User Group \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "packet-switching" target "http://groups.yahoo.com/group/packet-switching" \end_inset \begin_inset Newline newline \end_inset Description: This mailing list provides a forum for discussion of packet switching theory, technology, implementation and application in any relevant aspect including without limitation LAPB, X.25, SDLC, P802.1d, LLC, IP, IPv6, IPX, DECNET, APPLETALK, FR, PPP, IP Telephony, LAN PBX systems, management protocols like SNMP, e-mail, network transparent window systems, protocol implementation, protocol verification, conformance testing and tools used in maintaining or developing packet switching systems. \end_layout \begin_layout Itemize de.comm.protocols.tcp-ip \begin_inset Newline newline \end_inset Description: Umstellung auf IPv6 \begin_inset Newline newline \end_inset Source: \begin_inset CommandInset href LatexCommand href name "Chartas der Newsgruppen in de.*" target "http://www.faqs.org/faqs/de-newsgroups/chartas/index.html" \end_inset \end_layout \begin_layout Itemize Google Group: \begin_inset CommandInset href LatexCommand href name "comp.protocols.tcp-ip" target "http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&group=comp.protocols.tcp-ip" \end_inset \end_layout \begin_layout Itemize Google Group: \begin_inset CommandInset href LatexCommand href name "linux.debian.maint.ipv6" target "http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&group=linux.debian.maint.ipv6" \end_inset \end_layout \begin_layout Itemize Google Group: \begin_inset CommandInset href LatexCommand href name "microsoft.public.platformsdk.networking.ipv6" target "http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&group=microsoft.public.platformsdk.networking.ipv6" \end_inset \end_layout \begin_layout Itemize Google Group: \begin_inset CommandInset href LatexCommand href name "fa.openbsd.ipv6" target "http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&group=fa.openbsd.ipv6" \end_inset \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-onlinetesttools" \end_inset Online tools \end_layout \begin_layout Subsection Testing tools \end_layout \begin_layout Itemize ping, traceroute, tracepath, 6bone registry, DNS: \begin_inset CommandInset href LatexCommand href name "JOIN / Testtools" target "http://www.join.uni-muenster.de/lab/testtools.html" \end_inset (German language only, but should be no problem for non German speakers) \end_layout \begin_layout Itemize traceroute6, whois: \begin_inset CommandInset href LatexCommand href name "IPng.nl" target "http://www.ipng.nl/" \end_inset \end_layout \begin_layout Itemize AAAA Lookup Checker \begin_inset CommandInset href LatexCommand href name "http://www.cnri.dit.ie/cgi-bin/check_aaaa.pl" target "http://www.cnri.dit.ie/cgi-bin/check_aaaa.pl" \end_inset \end_layout \begin_layout Subsection Information retrievement \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "List of worldwide all IPv6-aggregated IP-Blocks" target "http://www.ripe.net/ripencc/mem-services/registration/ipv6/ipv6allocs.html" \end_inset \end_layout \begin_layout Subsection IPv6 Looking Glasses \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DRENv6 Looking Glass" target "http://www.v6.dren.net/lg/" \end_inset \end_layout \begin_layout Subsection Helper applications \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "IPv6 Prefix Calculator" target "http://www.tdoi.org/prefcalc.php" \end_inset by \begin_inset CommandInset href LatexCommand href name "TDOI" target "http://www.tdoi.org/" \end_inset \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "DNS record checker" target "http://www.maths.tcd.ie/cgi-bin/check_dns.pl" \end_inset \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-trainingsandseminars" \end_inset Trainings, Seminars \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "CIW Internetworking Professional Training CBT CD" target "http://www.e-trainonline.com/html/ciw_internetworking_profession.html#IPv6" \end_inset \end_layout \begin_layout Itemize \lang ngerman \begin_inset CommandInset href LatexCommand href name "Training Pages" target "http://www.trainingpages.com/x/category,kw-1628,.html" \end_inset \lang english , U.K. - Search for IPv6 (13 Courses, 2006-08-21) \end_layout \begin_layout Itemize \begin_inset CommandInset href LatexCommand href name "Erion IPv6 Training" target "http://www.erion.co.uk/ipv6.html" \end_inset , UK \end_layout \begin_layout Standard Something missing? Suggestions are welcome! \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "information-onlinediscovery" \end_inset 'The Online Discovery' ... \end_layout \begin_layout Standard IPv6: Addressing The Needs Of the Future by Yankee Group (Author) \begin_inset Newline newline \end_inset List Price: $595.00 \begin_inset Newline newline \end_inset Edition: e-book (Acrobat Reader) \begin_inset Newline newline \end_inset Pages: 3 (three) \begin_inset Newline newline \end_inset Publisher: MarketResearch.com; ISBN B00006334Y; (November 1, 2001) \begin_inset Newline newline \end_inset \end_layout \begin_layout Standard ;-) The number of copies would be interesting... \begin_inset Newline newline \end_inset \end_layout \begin_layout Chapter Revision history / Credits / The End \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "revision-history" \end_inset Revision history \end_layout \begin_layout Standard Versions x.y are published on the Internet. \end_layout \begin_layout Standard Versions x.y.z are work-in-progress and published as LyX and SGML file on CVS. Because Deep Space 6 mirrors these SGML files and generate independend from TLDP public versions, this versions will show up there and also on its mirrors. \end_layout \begin_layout Subsection Releases 0.x \end_layout \begin_layout Description 0.67wip 2015-08-18/PB: fix some broken URLs, 20151016/bie: remove broken URL to Spanish transation, 20161215/bie: update some URLs \end_layout \begin_layout Description 0.66 2010-04-20/PB: extend QoS section with examples, 20130513/PB: add IPv6 NAT hints, 20130521/PB: review dhcpd, 20131019/bie: general review, 20140502/bi e: add hints for nftables, 20140513/bie: extend section regarding address resolution and add source/destination address selection information, 20140515/b ie: add hints for activation of privacy extension \end_layout \begin_layout Description 0.65 2009-12-13/PB: minor fixes \end_layout \begin_layout Description 0.64 2009-06-11/PB: extend DHCP server examples (ISC DHCP, Dibbler) \end_layout \begin_layout Description 0.63 2009-02-14/PB: Fix FSF address, major update on 4in6 tunnels, add new section for address resolving, add some URLs, remove broken URLs \end_layout \begin_layout Description 0.62 2008-11-09/PB: Adjust URL to Turkish howto, add some HIP related URLs, remove broken URLs \end_layout \begin_layout Description 0.61.1 2007-11-11/PB: fix broken description of shortcut BIND \end_layout \begin_layout Description 0.61 2007-10-06/PB: fix broken URLs to TLDP-CVS, minor URL update. \end_layout \begin_layout Description 0.60.2 2007-10-03/PB: fix description of sysctl/autoconf (credits to Francois-Xavi er Le Bail) \end_layout \begin_layout Description 0.60.1 2007-06-16/PB: speling fixes (credits to Larry W. Burton) \end_layout \begin_layout Description 0.60 2007-05-29/PB: import major contribution to Programming using C-API written by John Wenker, minor fixes \end_layout \begin_layout Description 0.52 2007-05-23/PB: update firewalling chapter, improve document for proper SGML validation, minor bugfixes \end_layout \begin_layout Description 0.51 2006-11-08/PB: remove broken URLs, add a new book (credits to Bryan Vukich) \end_layout \begin_layout Description 0.50.2 2006-10-25/PB: fix typo in dhcp6 section (credits to Michele Ferritto) \end_layout \begin_layout Description 0.50.1 2006-09-23/PB: add some URLs \end_layout \begin_layout Description 0.50 2006-08-24/PB: check RFC URLs, fix URL to Chinese translation, finalize for publishing \end_layout \begin_layout Description 0.49.5 2006-08-23/PB: fix/remove broken URLs \end_layout \begin_layout Description 0.49.4 2006-08-21/PB: some review, update and enhancement of the content, replace old 6bone example addresses with the current defined ones. \end_layout \begin_layout Description 0.49.3 2006-08-20/PB: fix bug in maillist entries, 'mobility' is now a separate chapter \end_layout \begin_layout Description 0.49.2 2006-08-20/PB: update and cleanup of maillist entries \end_layout \begin_layout Description 0.49.1 2006-06-13/PB: major update of mobility section (contributed by Benjamin Thery) \end_layout \begin_layout Description 0.49 2005-10-03/PB: add configuration hints for DHCPv6, major broken URL cleanup (credits to Necdet Yucel) \end_layout \begin_layout Description 0.48.1 2005-01-15/PB: minor fixes \end_layout \begin_layout Description 0.48 2005-01-11/PB: grammar check and minor review of IPv6 IPsec section \end_layout \begin_layout Description 0.47.1 2005-01-01/PB: add information and examples about IPv6 IPsec, add some URLs \end_layout \begin_layout Description 0.47 2004-08-30/PB: add some notes about proftpd, vsftpd and other daemons, add some URLs, minor fixes, update status of Spanish translation \end_layout \begin_layout Description 0.46.4 2004-07-19/PB: minor fixes \end_layout \begin_layout Description 0.46.3 2004-06-23/PB: add note about started Greek translation, replace Taiwanese with Chinese for related translation \end_layout \begin_layout Description 0.46.2 2004-05-22/PB: minor fixes \end_layout \begin_layout Description 0.46.1 2004-04-18/PB: minor fixes \end_layout \begin_layout Description 0.46 2004-03-04/PB: announce Italian translation, add information about DHCPv6, minor updates \end_layout \begin_layout Description 0.45.1 2004-01-12/PB: add note about the official example address space \end_layout \begin_layout Description 0.45 2004-01-11/PB: minor fixes, add/fix some URLs, some extensions \end_layout \begin_layout Description 0.44.2 2003-10-30/PB: fix some copy&paste text bugs \end_layout \begin_layout Description 0.44.1 2003-10-19/PB: add note about start of Italian translation \end_layout \begin_layout Description 0.44 2003-08-15/PB: fix URLs, add hint on tcp_wrappers (about broken notation in some versions) and Apache2 \end_layout \begin_layout Description 0.43.4 2003-07-26/PB: fix URL, add archive URL for maillist users at ipv6.org, add some ds6 URLs \end_layout \begin_layout Description 0.43.3 2003-06-19/PB: fix typos \end_layout \begin_layout Description 0.43.2 2003-06-11/PB: fix URL \end_layout \begin_layout Description 0.43.1 2003-06-07/PB: fix some URLs, fix credits, add some notes at IPsec \end_layout \begin_layout Description 0.43 2003-06-05/PB: add some notes about configuration in SuSE Linux, add URL of French translation \end_layout \begin_layout Description 0.42 2003-05-09/PB: minor fixes, announce French translation \end_layout \begin_layout Description 0.41.4 2003-05-02/PB: Remove a broken URL, update some others. \end_layout \begin_layout Description 0.41.3 2003-04-23/PB: Minor fixes, remove a broken URL, fix URL to Taiwanese translation \end_layout \begin_layout Description 0.41.2 2003-04-13/PB: Fix some typos, add a note about a French translation is in progress \end_layout \begin_layout Description 0.41.1 2003-03-31/PB: Remove a broken URL, fix another \end_layout \begin_layout Description 0.41 2003-03-22/PB: Add URL of German translation \end_layout \begin_layout Description 0.40.2 2003-02-27/PB: Fix a misaddressed URL \end_layout \begin_layout Description 0.40.1 2003-02-12/PB: Add Debian-Linux-Configuration, add a minor note on translations \end_layout \begin_layout Description 0.40 2003-02-10/PB: Announcing available German version \end_layout \begin_layout Description 0.39.2 2003-02-10/GK: Minor syntax and spelling fixes \end_layout \begin_layout Description 0.39.1 2003-01-09/PB: fix an URL (draft adopted to an RFC) \end_layout \begin_layout Description 0.39 2003-01-13/PB: fix a bug (forgotten 'link \begin_inset Quotes srd \end_inset on \begin_inset Quotes sld \end_inset ip link set \begin_inset Quotes srd \end_inset (credits to Yaniv Kaul) \end_layout \begin_layout Description 0.38.1 2003-01-09/PB: a minor fix \end_layout \begin_layout Description 0.38 2003-01-06/PB: minor fixes \end_layout \begin_layout Description 0.37.1 2003-01-05/PB: minor updates \end_layout \begin_layout Description 0.37 2002-12-31/GK: 270 new links added (searched in 1232 SearchEngines) in existing and 53 new (sub)sections \end_layout \begin_layout Description 0.36.1 2002-12-20/PB: Minor fixes \end_layout \begin_layout Description 0.36 2002-12-16/PB: Check of and fix broken links (credits to Georg Käfer), some spelling fixes \end_layout \begin_layout Description 0.35 2002-12-11/PB: Some fixes and extensions \end_layout \begin_layout Description 0.34.1 2002-11-25/PB: Some fixes (e.g. broken linuxdoc URLs) \end_layout \begin_layout Description 0.34 2002-11-19/PB: Add information about German translation (work in progress), some fixes, create a small shortcut explanation list, extend \begin_inset Quotes sld \end_inset used terms \begin_inset Quotes srd \end_inset and add two German books \end_layout \begin_layout Description 0.33 2002-11-18/PB: Fix broken RFC-URLs, add parameter ttl on 6to4 tunnel setup example \end_layout \begin_layout Description 0.32 2002-11-03/PB: Add information about Taiwanese translation \end_layout \begin_layout Description 0.31.1 2002-10-06/PB: Add another maillist \end_layout \begin_layout Description 0.31 2002-09-29/PB: Extend information in proc-filesystem entries \end_layout \begin_layout Description 0.30 2002-09-27/PB: Add some maillists \end_layout \begin_layout Description 0.29 2002-09-18/PB: Update statement about nmap (triggered by Fyodor) \end_layout \begin_layout Description 0.28.1 2002-09-16/PB: Add note about ping6 to multicast addresses, add some labels \end_layout \begin_layout Description 0.28 2002-08-17/PB: Fix broken LDP/CVS links, add info about Polish translation, add URL of the IPv6 Address Oracle \end_layout \begin_layout Description 0.27 2002-08-10/PB: Some minor updates \end_layout \begin_layout Description 0.26.2 2002-07-15/PB: Add information neighbor discovery, split of firewalling (got some updates) and security into extra chapters \end_layout \begin_layout Description 0.26.1 2002-07-13/PB: Update nmap/IPv6 information \end_layout \begin_layout Description 0.26 2002-07-13/PB: Fill /proc-filesystem chapter, update DNS information about depricated A6/DNAME, change P-t-P tunnel setup to use of \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset only \end_layout \begin_layout Description 0.25.2 2002-07-11/PB: Minor spelling fixes \end_layout \begin_layout Description 0.25.1 2002-06-23/PB: Minor spelling and other fixes \end_layout \begin_layout Description 0.25 2002-05-16/PB: Cosmetic fix for 2^128, thanks to José Abílio Oliveira Matos for help with LyX \end_layout \begin_layout Description 0.24 2002-05-02/PB: Add entries in URL list, minor spelling fixes \end_layout \begin_layout Description 0.23 2002-03-27/PB: Add entries in URL list and at maillists, add a label and minor information about IPv6 on RHL \end_layout \begin_layout Description 0.22 2002-03-04/PB: Add info about 6to4 support in kernel series 2.2.x and add an entry in URL list and at maillists \end_layout \begin_layout Description 0.21 2002-02-26/PB: Migrate next grammar checks submitted by John Ronan \end_layout \begin_layout Description 0.20.4 2002-02-21/PB: Migrate more grammar checks submitted by John Ronan, add some additional hints at DNS section \end_layout \begin_layout Description 0.20.3 2002-02-12/PB: Migrate a minor grammar check patch submitted by John Ronan \end_layout \begin_layout Description 0.20.2 2002-02-05/PB: Add mipl to maillist table \end_layout \begin_layout Description 0.20.1 2002-01-31/PB: Add a hint how to generate 6to4 addresses \end_layout \begin_layout Description 0.20 2002-01-30/PB: Add a hint about default route problem, some minor updates \end_layout \begin_layout Description 0.19.2 2002-01-29/PB: Add many new URLs \end_layout \begin_layout Description 0.19.1 2002-01-27/PB: Add some forgotten URLs \end_layout \begin_layout Description 0.19 2002-01-25/PB: Add two German books, fix quote entinities in exported SGML code \end_layout \begin_layout Description 0.18.2 2002-01-23/PB: Add a FAQ on the program chapter \end_layout \begin_layout Description 0.18.1 2002-01-23/PB: Move \begin_inset Quotes sld \end_inset the end \begin_inset Quotes srd \end_inset to the end, add USAGI to maillists \end_layout \begin_layout Description 0.18 2002-01-22/PB: Fix bugs in explanation of multicast address types \end_layout \begin_layout Description 0.17.2 2002-01-22/PB: Cosmetic fix double existing text in history (at 0.16), move all credits to the end of the document \end_layout \begin_layout Description 0.17.1 2002-01-20/PB: Add a reference, fix URL text in online-test-tools \end_layout \begin_layout Description 0.17 2002-01-19/PB: Add some forgotten information and URLs about global IPv6 addresses \end_layout \begin_layout Description 0.16 2002-01-19/PB: Minor fixes, remove \begin_inset Quotes sld \end_inset bold \begin_inset Quotes srd \end_inset and \begin_inset Quotes sld \end_inset emphasize \begin_inset Quotes srd \end_inset formats on code lines, fix \begin_inset Quotes sld \end_inset too long unwrapped code lines \begin_inset Quotes srd \end_inset using selfmade utility, extend list of URLs. \end_layout \begin_layout Description 0.15 2002-01-15/PB: Fix bug in addresstype/anycast, move content related credits to end of document \end_layout \begin_layout Description 0.14 2002-01-14/PB: Minor review at all, new chapter \begin_inset Quotes sld \end_inset debugging \begin_inset Quotes srd \end_inset , review \begin_inset Quotes sld \end_inset addresses \begin_inset Quotes srd \end_inset , spell checking, grammar checking (from beginning to 3.4.1) by Martin Krafft, add tcpdump examples, copy firewalling/netfilter6 from IPv6+Linux-HowTo, minor enhancements \end_layout \begin_layout Description 0.13 2002-01-05/PB: Add example BIND9/host, move revision history to end of document, minor extensions \end_layout \begin_layout Description 0.12 2002-01-03/PB: Merge review of David Ranch \end_layout \begin_layout Description 0.11 2002-01-02/PB: Spell checking and merge review of Pekka Savola \end_layout \begin_layout Description 0.10 2002-01-02/PB: First public release of chapter 1 \end_layout \begin_layout Section \begin_inset CommandInset label LatexCommand label name "credits" \end_inset Credits \end_layout \begin_layout Standard The quickest way to be added to this nice list is to send bug fixes, corrections , and/or updates to me ;-). \end_layout \begin_layout Standard If you want to do a major review, you can use the native LyX file (see \begin_inset CommandInset ref LatexCommand ref name "original source" reference "general-original-source" \end_inset ) and send diffs against it, because diffs against SGML don't help too much. \end_layout \begin_layout Subsection \begin_inset CommandInset label LatexCommand label name "major-credits" \end_inset Major credits \end_layout \begin_layout Itemize David Ranch : For encouraging me to write this HOWTO, his editorial comments on the first few revisions, and his contributions to various IPv6 testing results on my IPv6 web site. Also for his major reviews and suggestions. \end_layout \begin_layout Itemize Pekka Savola : For major reviews, input and suggestion s. \end_layout \begin_layout Itemize Martin F. Krafft : For grammar checks and general reviewing of the document. \end_layout \begin_layout Itemize John Ronan : For grammar checks. \end_layout \begin_layout Itemize Georg Käfer : For detection of no proper PDF creation (fixed now by LDP maintainer Greg Ferguson), input for German books, big list of URLs, checking all URLs, many more suggestions, corrections and contributions, and the German translation \end_layout \begin_layout Itemize Michel Boucey : Finding typos and some broken URLs, contribute some suggestions and URLs, and the French translation \end_layout \begin_layout Itemize Michele Ferritto : Finding bugs and the Italian translation \end_layout \begin_layout Itemize Daniel Roesen : For grammar checks \end_layout \begin_layout Itemize Benjamin Thery : For contribution of updated mobility section \end_layout \begin_layout Itemize John Wenker : major contribution to Programming using C-API \end_layout \begin_layout Itemize Srivats P. : major contribution for 4in6 tunnels \end_layout \begin_layout Subsection Other credits \end_layout \begin_layout Subsubsection Document technique related \end_layout \begin_layout Standard Writing a LDP HOWTO as a newbie (in LyX and exporting this to DocBook to conform to SGML) isn't as easy as some people say. There are some strange pitfalls... Nevertheless, thanks to: \end_layout \begin_layout Itemize Authors of the \begin_inset CommandInset href LatexCommand href name "LDP Author Guide" target "http://www.tldp.org/LDP/LDP-Author-Guide/" \end_inset \end_layout \begin_layout Itemize B. Guillon: For his \begin_inset CommandInset href LatexCommand href name "DocBook with LyX HOWTO" target "http://perso.libertysurf.fr/bgu/doc/db4lyx/" \end_inset \end_layout \begin_layout Subsubsection \begin_inset CommandInset label LatexCommand label name "content-related-credits" \end_inset Content related credits \end_layout \begin_layout Standard Credits for fixes and hints are listed here, will grow sure in the future \end_layout \begin_layout Itemize S .P. Meenakshi : For a hint using a \begin_inset Quotes sld \end_inset send mail \begin_inset Quotes srd \end_inset shell program on tcp_wrapper/hosts.deny \end_layout \begin_layout Itemize Frank Dinies : For a bugfix on IPv6 address explanati on \end_layout \begin_layout Itemize John Freed : For finding a bug in IPv6 multicast address explanation \end_layout \begin_layout Itemize Craig Rodrigues : For suggestion about RHL IPv6 setup \end_layout \begin_layout Itemize Fyodor : Note me about outdated nmap information \end_layout \begin_layout Itemize Mauro Tortonesi : For some suggestions \end_layout \begin_layout Itemize Tom Goodale : For some suggestions \end_layout \begin_layout Itemize Martin Luemkemann : For a suggestion \end_layout \begin_layout Itemize Jean-Marc V. Liotier : Finding a bug \end_layout \begin_layout Itemize Yaniv Kaul : Finding a bug \end_layout \begin_layout Itemize Arnout Engelen : For sending note about a draft was adopted to RFC now \end_layout \begin_layout Itemize Stephane Bortzmeyer : Contributing persistent configuration on Debian \end_layout \begin_layout Itemize lithis von saturnsys : Reporting a misaddressed URL \end_layout \begin_layout Itemize Guy Hulbert : Send a note that RFC1924 is probably an April fool's joke \end_layout \begin_layout Itemize Tero Pelander : Reporting a broken URL \end_layout \begin_layout Itemize Walter Jontofsohn : Hints for SuSE Linux 8.0/8.1 \end_layout \begin_layout Itemize Benjamin Hofstetter : Reporting a mispointing URL \end_layout \begin_layout Itemize J.P. Larocque : Reporting archive URL for maillist users at ipv6 dot org \end_layout \begin_layout Itemize Jorrit Kronjee : Reporting broken URLs \end_layout \begin_layout Itemize Colm MacCarthaigh : Hint for sendfile issue on Apache2 \end_layout \begin_layout Itemize Tiago Camilo : Contribute some URLs about Mobile IPv6 \end_layout \begin_layout Itemize Harald Geiger: Reporting a bug in how described the bit counting of the universal/global bit \end_layout \begin_layout Itemize Bjoern Jacke : Triggered me to fix some outdated informati on on xinetd \end_layout \begin_layout Itemize Christoph Egger : Sending note about \begin_inset Quotes sld \end_inset ip \begin_inset Quotes srd \end_inset has problems with IPv4-compatible addresses on SuSE Linux 9.0 and trigger to add a hint on 6to4-radvd example \end_layout \begin_layout Itemize David Lee Haw Ling : Sending information about a tunnel broker \end_layout \begin_layout Itemize Michael H. Warfield : Sending note about suffix for 6to4 routers \end_layout \begin_layout Itemize Tomasz Mrugalski : Sending updates for DHCPv6 section \end_layout \begin_layout Itemize Jan Minar : Reporting minor bugs \end_layout \begin_layout Itemize Kalin KOZHUHAROV : Fixing a not so well explanation \end_layout \begin_layout Itemize Roel van Dijk : Reporting broken URLs \end_layout \begin_layout Itemize Catalin Muresan : Reporting minor bugs \end_layout \begin_layout Itemize Dennis van Dok : Reporting minor bugs \end_layout \begin_layout Itemize Necdet Yucel : Reporting broken URLs \end_layout \begin_layout Itemize Bryan Vukich: Reporting a broken URL \end_layout \begin_layout Itemize Daniele Masini: reporting a broken iptables example \end_layout \begin_layout Itemize Yao Zhao: reporting a bug in IPv6 route remove description \end_layout \begin_layout Itemize Aaron Kunde: reporting a broken URL and a content related bug \end_layout \begin_layout Itemize Larry W. Burton: speling fixes \end_layout \begin_layout Itemize Justin Pryzby: reporting broken shortcut description of BIND \end_layout \begin_layout Section The End \end_layout \begin_layout Standard Thanks for reading. Hope it helps! \end_layout \begin_layout Standard If you have any questions, subscribe to proper \begin_inset CommandInset ref LatexCommand ref name "maillist" reference "information-maillists" \end_inset and describe your problem providing as much as information as possible. \end_layout \end_body \end_document