Building, Installing, and Configuring sendmail 8.8.x Mini HOWTO
by John E. Gotts <jgotts@linuxsavvy.com>
v1.0, November 22, 1997

Attached is a patch for Makefile.Linux that turns on TCP wrappers and makes a
few other other harmless modifications.  (With TCP wrappers enabled you can
restrict remote access to your sendmail daemon according to the hosts_access(5)
man page). (1)  Assuming that you've saved it as sendmail.diff, apply it from
the directory below sendmail-8.8.x with:

patch -p0 < sendmail.diff

Change into the src directory and execute

./makesendmail

sendmail should build without any problems.

Henceforth I'm going to assume that you just use TCP/IP electronic mail.  UUCP
support is beyond the scope of this document.

Change into the cf/cf directory and create a new file, generic-linux2.mc:

divert(-1)
divert(0)dnl
VERSIONID(`@(#)generic-linux2.mc 8.8 (Local) 11/22/97')
OSTYPE(linux)dnl
FEATURE(nouucp)dnl
MAILER(local)dnl
MAILER(smtp)dnl

If you want to use masquerading, add the following two lines:

MASQUERADE_AS(<hostname>)dnl
EXPOSED_USER(root)dnl

This means that all the e-mail that gets sent from your machine (except e-mail
from root) will appear to have originated from the hostname that you specify.
(This option is useful for people with intermittent network connections, i.e.
users of SLIP and PPP, and for machines that have dynamically assigned IP
addresses via BOOTP or DHCP).  For sendmail versions 8.8.8 and newer, omit
EXPOSED_USER(root) as it has become the default behavior.

If you want to use procmail as your local mailer (standard practice with Red
Hat Linux), add:

FEATURE(local_procmail)dnl

Transform "generic-linux2.mc" into a sendmail.cf file:

m4 ../m4/cf.m4 generic-linux2.mc > obj/sendmail.cf

You might need to comment out

Cwlocalhost

in obj/sendmail.cf with a # sign as it appears to disrupt incoming e-mail on
newer Linux distributions.

Back up your old /etc/sendmail.cf file and install obj/sendmail.cf:

install -m 644 obj/sendmail.cf /etc/sendmail.cf

After you've installed your new sendmail.cf, kill the sendmail daemon, change
back into the src directory, and execute:

cd obj.Linux.*.* ; make install

This will install the sendmail binary and symbolic links.  You'll need to
install the manual pages by hand.

If you haven't opted to use procmail, change into the main sendmail directory
and type:

uudecode contrib/mail.local.linux
mv mail.local mail.local.old
tar zxvf mail.local.linux.tar.Z
cd mail.local
gcc -O3 -o mail.local mail.local.c
strip mail.local
install -m 2711 -g mail mail.local /bin
install -m 644 mail.local.8 /usr/man/man8

Your /var/spool/mail directory needs to be mode 775, owned by user root and
group mail.  Your mail clients need to be SGID mail (mode 2711 and owned by
user root and group mail).

Now you should be ready to restart your sendmail daemon.  Mine is started like
this:

/usr/sbin/sendmail -bd -q1h

NOTE: Red Hat 3.0.3 (and quite possibly 4.x) starts sendmail without its full
path name.  This can lead to problems such as preventing you from being able to
HUP sendmail to cause it to reread its configuration file.  To fix this, make
sure /etc/rc.d/init.d/sendmail.init starts sendmail as /usr/sbin/sendmail (with
the same arguments).

If you have an intermittent connection, you might want to start sendmail in
deferred mode:

/usr/sbin/sendmail -bd -o DeliveryMode=d

on boot and invoke sendmail as:

/usr/sbin/sendmail -q

to deliver all deferred e-mail when you first connect to the network and
periodically while you are connected (perhaps as a cron job).

At this point, you should test your new sendmail installation.  Here's one way
to do this:

% telnet localhost smtp
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 <hostname> ESMTP Sendmail 8.8.8/8.8.8; Fri, 22 Nov 1997 03:21:18 -0500
helo localhost
250 <hostname> Hello jgotts@localhost [127.0.0.1], pleased to meet you
mail from: jgotts
250 jgotts... Sender ok
rcpt to: jgotts
250 jgotts... Recipient ok
data
354 Enter mail, end with "." on a line by itself
This is a test.
.
250 DAA23297 Message accepted for delivery

Also, be sure to test that your e-mail clients still work and try sending a
test message to your machine from an outside source to verify that incoming
e-mail still works.

Footnotes:

(1) TCP wrapper support is broken in 8.8.8.  For a patch see

    http://linuxsavvy.com/resources/linux/sendmail-8.8.8-tcp-wrappers-patch

    While you're at it, you might as well also apply:

    http://linuxsavvy.com/resources/linux/sendmail-8.8.8-core-dump-patch

--- sendmail-8.8.8/src/Makefiles/Makefile.Linux.orig	Sun Jul  6 14:22:57 1997
+++ sendmail-8.8.8/src/Makefiles/Makefile.Linux	Sat Aug  9 03:46:24 1997
@@ -24,7 +24,7 @@
 #
 
 # use O=-O (usual) or O=-g (debugging)
-O=	-O
+O=	-O3
 
 # define the database mechanisms available for map & alias lookups:
 #	-DNDBM -- use new DBM
@@ -36,20 +36,20 @@
 DBMDEF=	-DNEWDB
 
 # environment definitions (e.g., -D_AIX3)
-ENVDEF=
+ENVDEF= -DTCPWRAPPERS
 
 # see also conf.h for additional compilation flags
 
 # include directories
-INCDIRS=-I/usr/local/include
+INCDIRS=
 
 # library directories
-LIBDIRS=-L/usr/local/lib
+LIBDIRS=
 
 # libraries required on your system
 #  you may need to add -lresolv if you've installed BIND on
 #  your system (see the BIND section for linux in src/READ_ME)
-LIBS=	-ldb
+LIBS=	-ldb -lwrap
 
 # location of sendmail binary (usually /usr/sbin or /usr/lib)
 BINDIR=	${DESTDIR}/usr/sbin
@@ -80,8 +80,8 @@
 	${DESTDIR}/usr/bin/hoststat ${DESTDIR}/usr/bin/purgestat
 INSTALL=install
 BINOWN=	root
-BINGRP=	kmem
-BINMODE=4555
+BINGRP=	0
+BINMODE=4711
 
 ALL=	sendmail aliases.0 mailq.0 newaliases.0 sendmail.0