270 lines
4.3 KiB
HTML
270 lines
4.3 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Installing sendmail</TITLE
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><META
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NAME="GENERATOR"
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TITLE="Linux Network Administrators Guide"
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TITLE="Sendmail"
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TITLE="Introduction to sendmail"
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><TD
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WIDTH="80%"
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>Chapter 18. Sendmail</TD
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><TD
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WIDTH="10%"
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><A
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CLASS="SECT1"
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><H1
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CLASS="SECT1"
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><A
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NAME="AEN14607"
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>18.2. Installing sendmail</A
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></H1
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><P
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>
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The <B
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CLASS="COMMAND"
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>sendmail</B
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> mail transport agent is included in
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prepackaged form in most Linux distributions. Installation in this case is
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relatively simple. Despite this fact, there are some good reasons to install
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<B
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CLASS="COMMAND"
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>sendmail</B
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> from source, especially if you are security
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conscious. The <B
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CLASS="COMMAND"
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>sendmail</B
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> program is very complex and has
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earned a reputation over the years for containing bugs that allow security
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breaches. One of the best known examples is the RTM Internet worm that
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exploited a buffer overflow problem in early versions of
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<B
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CLASS="COMMAND"
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>sendmail</B
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>. We touched on this briefly in
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<A
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HREF="x-087-2-firewall.html"
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>Chapter 9</A
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>. Most security exploits involving buffer
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overflows rely on all copies of <B
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CLASS="COMMAND"
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>sendmail</B
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> on different
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machines being identical, as the exploits rely on data being stored in
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specific locations. This, of course, is precisely what happens with
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<B
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CLASS="COMMAND"
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>sendmail</B
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> installed from Linux distributions. Compiling
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<B
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CLASS="COMMAND"
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>sendmail</B
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> from source yourself can help reduce this risk.
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Modern versions of <B
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CLASS="COMMAND"
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>sendmail</B
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> are less vulnerable because
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they have come under exceedingly close scrutiny as security has become a more
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widespread concern throughout the Internet community.</P
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><P
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> The <B
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CLASS="COMMAND"
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>sendmail</B
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> source code is available via anonymous FTP from
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<SPAN
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CLASS="SYSTEMITEM"
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>ftp.sendmail.org</SPAN
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>.</P
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><P
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>Compilation is very simple bceause the <B
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CLASS="COMMAND"
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>sendmail</B
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> source
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package directly supports Linux. The steps involved in compiling
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<B
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CLASS="COMMAND"
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>sendmail</B
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> are:
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<TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><PRE
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CLASS="SCREEN"
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><TT
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CLASS="USERINPUT"
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><B
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># cd /usr/local/src
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# tar xvfz sendmail.8.9.3.tar.gz
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# cd src
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# ./Build</B
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></TT
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></PRE
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></TD
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></TR
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></TABLE
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>
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You need <TT
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CLASS="LITERAL"
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>root</TT
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> permissions to complete the installation
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of the resulting binary files using:
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<TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><PRE
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CLASS="SCREEN"
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><TT
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CLASS="USERINPUT"
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><B
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># cd obj.Linux.2.0.36.i586
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# make install</B
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></TT
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></PRE
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></TD
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></TR
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></TABLE
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>
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You have now installed the <B
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CLASS="COMMAND"
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>sendmail</B
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> binary into the
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<TT
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CLASS="FILENAME"
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>/usr/sbin</TT
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> directory. Several symbolic links to
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the <B
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CLASS="COMMAND"
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>sendmail</B
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> binary will be installed into the
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<TT
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CLASS="FILENAME"
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>/usr/bin/</TT
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> directory. We'll talk about those links when
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we discuss common tasks in running <B
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CLASS="COMMAND"
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>sendmail</B
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>.</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="x14586.html"
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="index.html"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="x14644.html"
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>Next</A
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></TD
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></TR
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><TR
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><TD
|
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WIDTH="33%"
|
|
ALIGN="left"
|
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VALIGN="top"
|
|
>Introduction to sendmail</TD
|
|
><TD
|
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WIDTH="34%"
|
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ALIGN="center"
|
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VALIGN="top"
|
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><A
|
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HREF="x-087-2-sendmail.html"
|
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>Up</A
|
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
|
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VALIGN="top"
|
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>Overview of Configuration Files</TD
|
|
></TR
|
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></TABLE
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></DIV
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></BODY
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></HTML
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> |