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<!doctype linuxdoc system>
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<article>
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<!-- Title information -->
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<title>Chroot-BIND8 HOWTO
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<author>Scott Wunsch, <tt>scott at wunsch.org</>
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<date>v1.4, 1 July 2001
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<abstract>
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This document describes installing the BIND 8 nameserver to run in a chroot
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jail and as a non-root user, to provide added security and minimise the
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potential effects of a security compromise. This version of the document
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covers the old but still popular BIND 8; there is another document which
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provides similar information for BIND 9.
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</abstract>
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<!-- Table of contents -->
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<toc>
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<!-- Begin the document -->
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<sect>Introduction
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<p>
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This is the Chroot-BIND8 HOWTO; see <ref id="where" Name="Where?"> for the
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master site, which contains the latest copy. It is assumed that you already
|
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know how to configure and use BIND (the Berkeley Internet Name Domain). If
|
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not, I would recommend that you read the DNS HOWTO first. It is also assumed
|
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that you have a basic familiarity with compiling and installing software on
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your UNIX-like system.
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|
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<sect1>What?
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<p>
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This document describes some extra security precautions that you can take when
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you install BIND. It explains how to configure BIND so that it resides in a
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``chroot jail'', meaning that it cannot see or access files outside its own
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little directory tree. We shall also configure it to run as a non-root user.
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The idea behind chroot is fairly simple. When you run BIND (or any other
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process) in a chroot jail, the process is simply unable to see any part of the
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filesystem outside the jail. For example, in this document, we'll set BIND up
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to run chrooted to the directory <tt>/chroot/named</>. Well, to BIND, the
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contents of this directory will appear to be <tt>/</>, the root directory.
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Nothing outside this directory will be accessible to it. You've probably
|
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encounted a chroot jail before, if you've ever ftped into a public system.
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|
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<sect1>Why?
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|
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<p>
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The idea behind running BIND in a chroot jail is to limit the amount of access
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any malicious individual could gain by exploiting vulnerabilities in BIND. It
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is for the same reason that we run BIND as a non-root user.
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|
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This should be considered as a supplement to the normal security precautions
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(running the latest version, using access control, etc.), not a replacement for
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them.
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|
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If you're interested in DNS security, you might also be interested in a few
|
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other products. Building BIND with <url
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url="http://www.immunix.org/products.html#stackguard" name="StackGuard"> would
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probably be a good idea for even more protection. Using it is easy; it's
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just like using ordinary gcc. Also, <url
|
||||
url="http://cr.yp.to/dnscache.html" name="DNScache"> is a secure replacement
|
||||
for BIND, written by Dan Bernstein. Dan is the author of qmail, and DNScache
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||||
appears to follow a similar philosophy.
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|
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<sect1>Where?<label id="where">
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|
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<p>
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The latest version of this document is always available from the web site of the
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Linux/Open Source Users of Regina, Sask., at <url
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url="http://www.losurs.org/docs/howto/Chroot-BIND8.html">.
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There is now a Japanese translation of this document, maintained by <tt>nakano
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at apm.seikei.ac.jp</>. This is available at <url
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url="http://www.linux.or.jp/JF/JFdocs/Chroot-BIND8-HOWTO.html">.
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|
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BIND is available from <url url="http://www.isc.org/" name="the Internet
|
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Software Consortium"> at <url url="http://www.isc.org/bind.html">. As of this
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writing, the current version of BIND 8 is 8.2.4. BIND 9.x has now been
|
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released, and has been around for a little while. You may consider upgrading
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to it; the chroot process is certainly much simpler and cleaner. If you are
|
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running BIND 9, then you want the Chroot-BIND HOWTO, which should be available
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from the same location as this document.
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|
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Keep in mind that there are <bf>known</> security holes in all
|
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versions of BIND 8 less than <bf>8.2.3</>, so make very sure that you're
|
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running the latest version!
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|
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<sect1>How?
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|
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<p>
|
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I wrote this document based on my experiences in setting BIND up in a chroot
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environment. In my case, I already had an existing BIND installation in the
|
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form of a package that came with my Linux distribution. I'll assume that most
|
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of you are probably in the same situation, and will simply be transferring over
|
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and modifying the configuration files from your existing BIND installation, and
|
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then removing the package before installing the new one. Don't remove the
|
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package yet, though; we may want some files from it first.
|
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|
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If this is not the case for you, you should still be able to follow this
|
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document. The only difference is that, where I refer to copying an existing
|
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file, you first have to create it yourself. The DNS HOWTO may be helpful for
|
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this.
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|
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<sect1>Disclaimer
|
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|
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<p>
|
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These steps worked for me, on my system. Your mileage may vary. This is but
|
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one way to approach this; there are other ways to set the same thing up
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(although the general approach will be the same). It just happens that this
|
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was the first way that I tried that worked, so I wrote it down.
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|
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My BIND experience to date has been installing on Linux servers. However, most
|
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of the instructions in this document should be easily applicable to other
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flavours of UNIX as well, and I shall try to point out differences of which I am
|
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aware.
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|
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<sect>Preparing the Jail
|
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|
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<sect1>Creating a User
|
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|
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<p>
|
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As mentioned in the introduction, it's not a good idea to run BIND as root. So,
|
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before we begin, let's create a separate user for BIND. Note that you should
|
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never use an existing generic user like <tt>nobody</> for this purpose.
|
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However, some distributions, such as SuSE and Linux Mandrake have started
|
||||
providing a specific user (generally called <tt>named</>); you can simply adapt
|
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this user for our purposes, if you like.
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|
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This requires adding a line something like the following to <tt>/etc/passwd</>:
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<tscreen><verb>
|
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named:x:200:200:Nameserver:/chroot/named:/bin/false
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</verb></tscreen>
|
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And one like this to <tt>/etc/group</>:
|
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<tscreen><verb>
|
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named:x:200:
|
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</verb></tscreen>
|
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This creates a user and group called <tt>named</> for BIND. Make sure that the
|
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UID and GID (both 200 in this example) are unique on your system. The shell is
|
||||
set to <tt>/bin/false</> because this user will never need to log in.
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|
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<sect1>Directory Structure
|
||||
|
||||
<p>
|
||||
Now, we must set up the directory structure that we will use for the chroot jail
|
||||
in which BIND will live. This can be anywhere on your filesystem; the truly
|
||||
paranoid may even want to put it on a separate volume. I shall assume that you
|
||||
will use <tt>/chroot/named</>. Let's start by creating the following directory
|
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structure:
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|
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<tscreen><verb>
|
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/chroot
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+-- named
|
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+-- bin
|
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+-- dev
|
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+-- etc
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| +-- namedb
|
||||
+-- lib
|
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+-- var
|
||||
+-- run
|
||||
</verb></tscreen>
|
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|
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<sect1>Placing the BIND Data
|
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|
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<p>
|
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Assuming that you have already done a conventional installation of BIND and are
|
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using it, you will already have an existing <tt>named.conf</> and zone files.
|
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These files must now be moved (or copied, to be safe) into the chroot jail, so
|
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that BIND can get at them. <tt>named.conf</> goes in <tt>/chroot/named/etc</>,
|
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and the zone files can go in <tt>/chroot/named/etc/namedb</>. For example:
|
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<tscreen><verb>
|
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# cp -p /etc/named.conf /chroot/named/etc/
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|
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# cp -a /var/named/* /chroot/named/etc/namedb/
|
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</verb></tscreen>
|
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|
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BIND will likely need to write to the <tt>namedb</> directory, and probably some
|
||||
of the files in it. For example, if your DNS serves as a slave for a zone, it
|
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will have to update that zone file. Also, BIND can dump statistical
|
||||
information, and does so in this directory. For that reason, you should
|
||||
probably make the <tt>named</> user the owner of this directory and its contents:
|
||||
<tscreen><verb>
|
||||
# chown -R named:named /chroot/named/etc/namedb
|
||||
</verb></tscreen>
|
||||
BIND will also need to write to the <tt>/var/run</> directory, to put its
|
||||
pidfile and ndc socket there, so let's allow it to do so:
|
||||
<tscreen><verb>
|
||||
# chown named:named /chroot/named/var/run
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||||
</verb></tscreen>
|
||||
|
||||
<sect1>System Support Files
|
||||
|
||||
<p>
|
||||
Once BIND is running in the chroot jail, it will not be able to access files
|
||||
outside the jail <bf>at all</>. However, it needs to access a few key files, such
|
||||
as the system's C library. Exactly what libraries are required will depend on
|
||||
your flavour of UNIX. For most modern Linux systems, the following commands
|
||||
will be sufficient to put the necessary libraries in place:
|
||||
<tscreen><verb>
|
||||
# cd /chroot/named/lib
|
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# cp -p /lib/libc-2.*.so .
|
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# ln -s libc-2.*.so libc.so.6
|
||||
# cp -p /lib/ld-2.*.so .
|
||||
# ln -s ld-2.*.so ld-linux.so.2
|
||||
</verb></tscreen>
|
||||
As an alternative, you could simply build statically-linked versions of the BIND
|
||||
binaries to put in your chroot jail. You should also copy <tt>ldconfig</> into
|
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the jail, and run it to create an <tt>etc/ld.so.cache</> for the jail environment.
|
||||
The following commands could take care of this:
|
||||
<tscreen><verb>
|
||||
# cp /sbin/ldconfig /chroot/named/bin/
|
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# chroot /chroot/named /bin/ldconfig -v
|
||||
</verb></tscreen>
|
||||
|
||||
BIND needs one more system file in its jail: good ol' <tt>/dev/null</>. Again,
|
||||
the exact command necessary to create this device node may vary from system to
|
||||
system; check your <tt>/dev/MAKEDEV</> script to be sure. Some systems may also
|
||||
require <tt>/dev/zero</>. For most Linux systems, we can use the following
|
||||
command:
|
||||
<tscreen><verb>
|
||||
# mknod /chroot/named/dev/null c 1 3
|
||||
</verb></tscreen>
|
||||
|
||||
Finally, you need a couple extra files in the <tt>/etc</> directory inside the
|
||||
jail. In particular, you must copy <tt>/etc/localtime</> (this sometimes known
|
||||
as <tt>/usr/lib/zoneinfo/localtime</> on some systems) in there so that BIND
|
||||
logs things with the right time on them, and you must make a simple <tt>group</>
|
||||
file with the <tt>named</> group in it. The following two commands will take
|
||||
care of this:
|
||||
<tscreen><verb>
|
||||
# cp /etc/localtime /chroot/named/etc/
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||||
|
||||
# echo 'named:x:200:' > /chroot/named/etc/group
|
||||
</verb></tscreen>
|
||||
|
||||
Keep in mind that the GID, 200 in this example, must match the one you defined
|
||||
in the real <tt>/etc/group</> above.
|
||||
|
||||
<sect1>Logging<label id="logging">
|
||||
|
||||
<p>
|
||||
Unlike a conventional jailbird, BIND can't just scribble its log entries on the
|
||||
walls :-). Normally, BIND logs through <tt>syslogd</>, the system logging daemon.
|
||||
However, this type of logging is performed by sending the log entries to the
|
||||
special socket <tt>/dev/log</>. Since this is outside the jail, BIND can't use
|
||||
it any more. Fortuantely, there are a couple options to work around this.
|
||||
|
||||
<sect2>The Ideal Solution
|
||||
|
||||
<p>
|
||||
The ideal solution to this dilemma requires a reasonably recent version of
|
||||
<tt>syslogd</> which supports the <tt>-a</> switch introduced by OpenBSD.
|
||||
Check the manpage for your <tt>syslogd(8)</> to see if you have such a
|
||||
version.
|
||||
|
||||
If you do, all you have to do is add the switch ``<tt>-a
|
||||
/chroot/named/dev/log</>'' to the command line when you launch <tt>syslogd</>.
|
||||
On systems which use a full SysV-init (which includes most Linux distributions),
|
||||
this is typically done in the file <tt>/etc/rc.d/init.d/syslog</>. For example,
|
||||
on my Red Hat Linux system, I changed the line
|
||||
<tscreen><verb>
|
||||
daemon syslogd -m 0
|
||||
</verb></tscreen>
|
||||
to
|
||||
<tscreen><verb>
|
||||
daemon syslogd -m 0 -a /chroot/named/dev/log
|
||||
</verb></tscreen>
|
||||
|
||||
On Caldera OpenLinux systems, they use a daemon launcher called <tt>ssd</>,
|
||||
which reads configuration from <tt>/etc/sysconfig/daemons/syslog</>. You
|
||||
simply need to modify the options line to look like this:
|
||||
<tscreen><verb>
|
||||
OPTIONS_SYSLOGD="-m 0 -a /chroot/named/dev/log"
|
||||
</verb></tscreen>
|
||||
|
||||
Similarly, on SuSE systems, I'm told that the best place to add this switch
|
||||
is in the <tt>/etc/rc.config</> file. Changing the line
|
||||
<tscreen><verb>
|
||||
SYSLOGD_PARAMS=""
|
||||
</verb></tscreen>
|
||||
to read
|
||||
<tscreen><verb>
|
||||
SYSLOGD_PARAMS="-a /chroot/named/dev/log"
|
||||
</verb></tscreen>
|
||||
should do the trick.
|
||||
|
||||
Once you've figured out how to make this change for your system, simply
|
||||
restart <tt>syslogd</>, either by killing it and launching it again (with
|
||||
the extra parameters), or by using the SysV-init script to do it for you:
|
||||
<tscreen><verb>
|
||||
# /etc/rc.d/init.d/syslog stop
|
||||
# /etc/rc.d/init.d/syslog start
|
||||
</verb></tscreen>
|
||||
|
||||
Once it's been restarted, you should see a ``file'' in <tt>/chroot/named/dev</>
|
||||
called <tt>log</>, that looks something like this:
|
||||
|
||||
<verb>srw-rw-rw- 1 root root 0 Mar 13 20:58 log</verb>
|
||||
|
||||
<sect2>The Other Solutions
|
||||
|
||||
<p>
|
||||
If you have an older <tt>syslogd</>, then you'll have to find another way to do
|
||||
your logging. There are a couple programs out there, such as <tt>holelogd</>,
|
||||
which are designed to help by acting as a ``proxy'' and accepting log entries
|
||||
from the chrooted BIND and passing them out to the regular <tt>/dev/log</>
|
||||
socket.
|
||||
|
||||
Alteratively, you can simply configure BIND to log to files instead of going
|
||||
through syslog. See the BIND documentation for more details if you choose to go
|
||||
this route.
|
||||
|
||||
<sect>Compiling BIND<label id="compiling">
|
||||
|
||||
<p>
|
||||
You should be able to find the BIND source by visiting <url
|
||||
url="http://www.isc.org/bind.html">. You need the <tt>bind-src.tar.gz</>
|
||||
package. Be sure to get the latest version!
|
||||
|
||||
<sect1>Modifying Paths
|
||||
|
||||
<p>
|
||||
Things can get a bit confusing at this point, because different parts of the
|
||||
BIND package will be referring to the same directories by different names
|
||||
(depending on whether or not they're running inside the jail). I'll try not to
|
||||
confuse you <bf>too</> much :-).
|
||||
|
||||
The main directory that we have to worry about here is <tt>/var/run</>, because
|
||||
its contents are required for both the main <tt>named</> daemon (inside the
|
||||
jail), and the <tt>ndc</> utility (on the outside). We'll start by setting
|
||||
everything up to find this directory from the outside world. To do this, we
|
||||
need to modify <tt>src/port/linux/Makefile.set</> (substitute your port's
|
||||
directory if you're not running Linux), and change the line
|
||||
<tscreen><verb>
|
||||
DESTRUN=/var/run
|
||||
</verb></tscreen>
|
||||
to
|
||||
<tscreen><verb>
|
||||
DESTRUN=/chroot/named/var/run
|
||||
</verb></tscreen>
|
||||
While you're in there, you may want to change the other destination paths from
|
||||
<tt>/usr</> to <tt>/usr/local</>.
|
||||
|
||||
Now everything should be able to find that directory... except the <tt/named/
|
||||
daemon itself, to which it's still just <tt>/var/run</> inside the jail. We can
|
||||
get around this by making a small change in the <tt/named/ source. In the file
|
||||
<tt>src/bin/named/named.h</>, find the line
|
||||
<tscreen><verb>
|
||||
#include "pathnames.h"
|
||||
</verb></tscreen>
|
||||
and add the following line immediately after it
|
||||
<tscreen><verb>
|
||||
#define _PATH_NDCSOCK "/var/run/ndc"
|
||||
</verb></tscreen>
|
||||
This way, <tt/named/ will ignore our definition of <tt/DESTRUN/ over in
|
||||
<tt/Makefile.set/ and use the correct location (from its perspective in the
|
||||
chroot jail). You will notice some warnings about redefinitions of
|
||||
_PATH_NDCSOCK when you do the build; just ignore them.
|
||||
|
||||
<sect1>Doing the Build
|
||||
|
||||
<p>
|
||||
You should now be able to compile BIND as normal, following the instructions in
|
||||
the <tt/INSTALL/ file. At this stage, we only want to compile BIND, not install
|
||||
it. Don't go too far when following the <tt/INSTALL/ file. Essentially, it's
|
||||
just <tt/make clean/, <tt/make depend/, and <tt/make/.
|
||||
|
||||
<sect>Installing Your Shiny New BIND<label id="installing">
|
||||
|
||||
<p>
|
||||
I should mention that if you have an existing installation of BIND, such as from
|
||||
an RPM, you should probably remove it before installing the new one. On Red Hat
|
||||
systems, this probably means removing the packages <tt/bind/ and
|
||||
<tt/bind-utils/, and possibly <tt/bind-devel/ and <tt/caching-nameserver/, if
|
||||
you have them.
|
||||
|
||||
You may want to save a copy of the init script (e.g.,
|
||||
<tt>/etc/rc.d/init.d/named</>), if any, before doing so; it'll be useful later
|
||||
on.
|
||||
|
||||
<sect1>Installing the Tools Outside the Jail
|
||||
|
||||
<p>
|
||||
This is the easy part :-). Just run <tt/make install/ and let it take care of
|
||||
it for you. You may want to <tt>chmod 000 /usr/local/sbin/named</> afterwards,
|
||||
to make sure you don't accidentally run the non-chrooted copy of BIND. (This
|
||||
is <tt>/usr/sbin/named</> if you didn't tell it to go in <tt>/usr/local/sbin</>
|
||||
like I suggested.)
|
||||
|
||||
<sect1>Installing the Binaries in the Jail
|
||||
|
||||
<p>
|
||||
Only two parts of the package have to live inside the chroot jail: the main
|
||||
<tt/named/ daemon itself, and <tt/named-xfer/, which it uses for zone transfers.
|
||||
You can simply copy them in from the source tree:
|
||||
<tscreen><verb>
|
||||
# cp src/bin/named/named /chroot/named/bin
|
||||
|
||||
# cp src/bin/named-xfer/named-xfer /chroot/named/bin
|
||||
</verb></tscreen>
|
||||
|
||||
<sect1>Setting up the Init Script
|
||||
|
||||
<p>
|
||||
If you have an existing init script from your distribution, it would probably be
|
||||
best simply to modify it to run <tt>/chroot/named/bin/named</>, with the
|
||||
appropriate switches. The switches are... <it/(drumroll please...)/
|
||||
<itemize>
|
||||
<item><tt/-u named/, which tells BIND to run as the user <tt/named/, rather than
|
||||
<tt/root/.
|
||||
<item><tt/-g named/, to run BIND under the group <tt/named/ too, rather than
|
||||
<tt/root/ or <tt/wheel/.
|
||||
<item><tt>-t /chroot/named</>, which tells BIND to chroot itself to the jail
|
||||
that we've set up.
|
||||
</itemize>
|
||||
|
||||
The following is the init script I use with my Red Hat 6.0 system. As you can
|
||||
see, it is almost exactly the same as the way it shipped from Red Hat. I have
|
||||
also modified the <tt>ndc restart</> command so that it restarts the server
|
||||
properly, and keeps it chrooted. You should probably do the same in your init
|
||||
script, even if you don't copy this one.
|
||||
<tscreen><code>
|
||||
#!/bin/sh
|
||||
#
|
||||
# named This shell script takes care of starting and stopping
|
||||
# named (BIND DNS server).
|
||||
#
|
||||
# chkconfig: 345 55 45
|
||||
# description: named (BIND) is a Domain Name Server (DNS) \
|
||||
# that is used to resolve host names to IP addresses.
|
||||
# probe: true
|
||||
|
||||
# Source function library.
|
||||
. /etc/rc.d/init.d/functions
|
||||
|
||||
# Source networking configuration.
|
||||
. /etc/sysconfig/network
|
||||
|
||||
# Check that networking is up.
|
||||
[ ${NETWORKING} = "no" ] && exit 0
|
||||
|
||||
[ -f /chroot/named/bin/named ] || exit 0
|
||||
|
||||
[ -f /chroot/named/etc/named.conf ] || exit 0
|
||||
|
||||
# See how we were called.
|
||||
case "$1" in
|
||||
start)
|
||||
# Start daemons.
|
||||
echo -n "Starting named: "
|
||||
daemon /chroot/named/bin/named -u named -g named -t /chroot/named
|
||||
echo
|
||||
touch /var/lock/subsys/named
|
||||
;;
|
||||
stop)
|
||||
# Stop daemons.
|
||||
echo -n "Shutting down named: "
|
||||
killproc named
|
||||
rm -f /var/lock/subsys/named
|
||||
echo
|
||||
;;
|
||||
status)
|
||||
/usr/local/sbin/ndc status
|
||||
exit $?
|
||||
;;
|
||||
restart)
|
||||
/usr/local/sbin/ndc -n /chroot/named/bin/named "restart -u named -g named -t /chroot/named"
|
||||
exit $?
|
||||
;;
|
||||
reload)
|
||||
/usr/local/sbin/ndc reload
|
||||
exit $?
|
||||
;;
|
||||
probe)
|
||||
# named knows how to reload intelligently; we don't want linuxconf
|
||||
# to offer to restart every time
|
||||
/usr/local/sbin/ndc reload >/dev/null 2>&1 || echo start
|
||||
exit 0
|
||||
;;
|
||||
|
||||
*)
|
||||
echo "Usage: named {start|stop|status|restart}"
|
||||
exit 1
|
||||
esac
|
||||
|
||||
exit 0
|
||||
</code></tscreen>
|
||||
|
||||
On Caldera OpenLinux systems, you simply need to modify the variables defined
|
||||
at the top, and it will apparently take care of the rest for you:
|
||||
<tscreen><verb>
|
||||
NAME=named
|
||||
DAEMON=/chroot/named/bin/$NAME
|
||||
OPTIONS="-t /chroot/named -u named -g named"
|
||||
</verb></tscreen>
|
||||
|
||||
<sect1>Configuration Changes
|
||||
|
||||
<p>
|
||||
You will also have to add or change a few options in your <tt>named.conf</> to
|
||||
keep the various directories straight. In particular, you should add (or
|
||||
change, if you already have them) the following directives in the <tt>options</>
|
||||
section:
|
||||
<tscreen><verb>
|
||||
directory "/etc/namedb";
|
||||
pid-file "/var/run/named.pid";
|
||||
named-xfer "/bin/named-xfer";
|
||||
</verb></tscreen>
|
||||
Since this file is being read by the <tt>named</> daemon, all the paths are of
|
||||
course relative to the chroot jail.
|
||||
|
||||
Some people have also reported having to add an extra block to their
|
||||
<tt>named.conf</> to get <tt>ndc</> working properly:
|
||||
<tscreen><verb>
|
||||
controls {
|
||||
unix "/var/run/ndc" perm 0600 owner 0 group 0;
|
||||
};
|
||||
</verb></tscreen>
|
||||
|
||||
<sect>The End
|
||||
|
||||
<sect1>Launching BIND
|
||||
|
||||
<p>
|
||||
Everything should be set up, and you should be ready to put your new, more
|
||||
secure BIND into action. Assuming you set up a SysV-style init script, you can
|
||||
simply launch it as:
|
||||
<tscreen><verb>
|
||||
# /etc/rc.d/init.d/named start
|
||||
</verb></tscreen>
|
||||
Make sure you kill any old versions of BIND still running before doing this.
|
||||
|
||||
If you take a look at your logs, you should find the initialisation messages
|
||||
that BIND spits out when it loads. (If not, there's a problem with your <ref
|
||||
id="logging" name="logging configuration"> that you need to fix.) Amongst those
|
||||
messages, BIND should tell you that it chrooted successfully, and that it is
|
||||
running as the user and group <tt>named</>. If not, you have a problem.
|
||||
|
||||
<sect1>That's It!
|
||||
|
||||
<p>
|
||||
You can go take a nap now ;-).
|
||||
|
||||
<sect>Appendix - Upgrading BIND Later<label id="upgrading">
|
||||
|
||||
<p>So, you had BIND 8.2.2_P7 all nicely chrooted and tweaked to your taste...
|
||||
and then you hear this nasty rumour that there's a remotely-exploitable root
|
||||
hole in that version too, and you need to upgrade to 8.2.3 right away. Do
|
||||
you have to go through this whole long process to install this new version?
|
||||
|
||||
Nope. In fact, you really just need the section on <ref id="compiling"
|
||||
name="Compiling BIND"> and the first two parts of the section on <ref
|
||||
id="installing" name="Installing BIND"> (installing the binaries outside and
|
||||
inside the jail, respectively).
|
||||
|
||||
The rest of the HOWTO deals with setting up the jail and other things like
|
||||
that, which shouldn't need to be altered between versions of BIND. You can
|
||||
just dump the new binaries in over top of the old ones, and you're good to go.
|
||||
But don't forget to kill and restart BIND afterwards, or the old, vulnerable
|
||||
version will still be running!
|
||||
|
||||
<sect>Appendix - Thanks<label id="thanks">
|
||||
|
||||
<p>
|
||||
I'd like to thank the following people for their assistance in the creation
|
||||
of this HOWTO:
|
||||
|
||||
<itemize>
|
||||
|
||||
<item>Lonny Selinger <tt><lonny at abyss.za.org></> for "testing" the
|
||||
first version of this HOWTO and making sure that I didn't miss any steps.
|
||||
|
||||
<item>Chirik <tt><chirik at CastleFur.COM></>, Dwayne Litzenberger
|
||||
<tt><dlitz at dlitz.net></>, Phil Bambridge <tt><phil.b at
|
||||
cableinet.co.uk></>, Robert Cole <tt><rcole at metrum-datatape.com></>,
|
||||
Colin MacDonald <tt><colinm at telus.net></>, and others for pointing out
|
||||
errors, omissions, and providing other useful advice to make this HOWTO even
|
||||
better.
|
||||
|
||||
<item>Erik Wallin <tt><erikw at sec.se></> and Brian Cervenka
|
||||
<tt><brian at zerobelow.org></> for providing good suggestions for
|
||||
further tightening the jail.
|
||||
|
||||
</itemize>
|
||||
|
||||
And last but certainly not least, I'd like to thank Nakano Takeo <tt><nakano
|
||||
at apm.seikei.ac.jp></> for translating the Chroot-BIND HOWTO into
|
||||
Japanese. You can find his translation at <url
|
||||
url="http://www.linux.or.jp/JF/JFdocs/Chroot-BIND-HOWTO.html">.
|
||||
|
||||
<sect>Appendix - Document Distribution Policy<label id="legal">
|
||||
|
||||
<p>
|
||||
Copyright © Scott Wunsch, 2000-2001. This document may be distributed only
|
||||
subject to the terms set forth in the LDP licence at <url
|
||||
url="http://metalab.unc.edu/LDP/COPYRIGHT.html">.
|
||||
|
||||
This HOWTO is free documentation; you can redistribute it and/or modify it under
|
||||
the terms of the LDP licence. It is distributed in the hope that it will be
|
||||
useful, but <bf>without any warranty</>; without even the impled warranty of
|
||||
merchantability or fitness for a particular purpose. See the LDP licence for
|
||||
more details.
|
||||
|
||||
</article>
|
||||
Loading…
Reference in New Issue