V8 sendmail is available from:
When you cd into this directory, a banner is displayed that describes the latest release and available patches. You may choose between two forms of compressed tar(1) distributions. Those that end in .Z are compressed with UNIX compress(1); those that end in .gz are compressed with GNU gzip(1). The latter is the preferred form because the file is smaller and quicker to transfer.
In addition to the two forms of distribution, each release has associated with it a PGP signature file. It is a signature of the uncompressed file, so you need to uncompress the tar(1) file before verifying it. To verify a pre-V8.6 distribution, get Eric Allman's public key by sending email to [email protected] with the following subject line:
Subject: MGET Allman
Eric Allman's public key will be mailed back to you a few minutes later. [2] Save that returned email to a file, for example /tmp/eric.asc, and add that key to your public "keyring" with the command:
[2] As an alternative, you can run the command
finger -l [email protected] > /tmp/eric.ascand use that PGP information in place of the email information. They are equivalent.
pgp -ka /tmp/eric.asc
For V8.6 and above, you download a special signing key from www.sendmail.org, instead of Eric's key. The fingerprint for the signing key is:
CA AE F2 94 3B 1D 41 3C 94 7B 72 5F AE 0B 6A 11
The fingerprint for Eric's key is:
C0 28 E6 7B 13 5B 29 02 6F 7E 43 3A 48 4F 45 29
then execute:
pgp signature file here
If the uncompressed tar file is good, pgp(1) will report the following or some variation on it:
Good signature from user "Eric P. Allman <[email protected]>".
A few things can go wrong here, causing the verification to fail:
Signature and tar(1) files must match each other's versions. Transfer them again, this time with matching versions.
When transferring the files with ftp(1), you must be sure to use binary mode. Transfer them again, this time with the correct mode.
A presumed mirror FTP site might not be as official as you expect. If a secondary distribution fails to verify, get the official distributions from the official site shown above.
The official distribution may appear bad. If it fails to verify, first check that your copy of pgp was correctly installed, then check that your network connection is clean and that it has not been compromised. If all else fails (including getting the distribution anew as above), describe your problem to the folks at [email protected].
If your copy of the sendmail distribution fails to verify, don't use it!
V8.8.6 sendmail unpacks by creating a directory, then unpacking into that directory. The directory name is the same as the compressed file name but with the first dot a dash instead:
%zcat sendmail.8.8.6.tar.Z | tar xvf -
x sendmail-8.8.6/FAQ, 32312 bytes, 64 tape blocks x sendmail-8.8.6/KNOWNBUGS, 4714 bytes, 10 tape blocks x sendmail-8.8.6/Makefile, 1215 bytes, 3 tape blocks ... and so on
Inside the newly created directory you will find the full sendmail distribution:
%cd sendmail-8.8.6
%ls
FAQ RELEASE_NOTES mail.local rmail KNOWNBUGS cf mailstats smrsh Makefile contrib makemap src READ_ME doc praliases test
The READ_ME and RELEASE_NOTES files provide the most up-to-date information about changes, new features, and bug fixes. Read the documents in the doc directory. Also note that there are important comments in the src/READ_ME and cf/README files.
You will find almost everything you need to build sendmail in the src subdirectory. There are a few exceptions that we will cover in this chapter.
The first step in compiling sendmail is to establish an object directory and a Makefile that is appropriate to your machine architecture and operating system. You do this by running the makesendmail script in the src directory:
%cd src
%./makesendmail -n
Configuration: os=SunOS, rel=4.1.4, rbase=4, arch=sun4, sfx= Creating obj.SunOS.4.1.4.sun4 using Makefile.SunOS Making dependencies in obj.SunOS.4.1.4.sun4 many more lines here %
Here, makesendmail found that ours was a sun4
machine,
running the SunOS 4.1.4 release of UNIX. It created the working
directory obj.SunOS.4.1.4.sun4, set up symbolic links to
all the source files
in that directory, and copied a Makefile there.
The -n
switch
[3]
prevents make from actually
building sendmail.
Note that, except for the -m
switch, all command-line arguments following
the makesendmail are passed to make(1) as its own command-line arguments.
[3] As an alternative, the
-m
command-line switch causes makesendmail to print the name of your Makefile without actually creating the obj.* subdirectory.
The makesendmail script knows how to build sendmail on many versions of UNIX, including offshoots such as OSF/1 and NextStep. In the unlikely case that your operating system is not supported, you will see an error message instead of the above output:
Configuration: os=EX/Unix, rel=1, rbase=1, arch=sun4, sfx= Cannot determine how to support sun4.EX/Unix.1
Here, an experimental version of UNIX called EX/Unix on a
sun4 computer was unrecognized by the makesendmail
script. Porting sendmail to new operating systems is really
beyond the scope of this book. But we offer a complete listing
of #define
macros in Section 18.8 at the
end of this chapter, and that, as well as
much of the tuning that we discuss here, can also be germane to porting.
Before you let makesendmail run to completion, you may need to tune three of sendmail's files for your site:
*
Specifies where to install the binaries and how to compile them. Makefile is normally the only file you will have to modify if you are running an already supported operating system
Specifies maximum sizes and other properties that are tunable for porting:
Specifies C language code to support specific and unusual needs. Tunable items in conf.c include the checkcompat() routine (see Chapter 20, The checkcompat() Cookbook) and default header behavior (see Section 35.5, "Header Behavior in conf.c").