Exim-4.98

groupadd -g 31 exim &&
useradd -d /dev/null -c "Exim Daemon" -g exim -s /bin/false -u 31 exim

sed -e 's,^BIN_DIR.*$,BIN_DIRECTORY=/usr/sbin,'    \
    -e 's,^CONF.*$,CONFIGURE_FILE=/etc/exim.conf,' \
    -e 's,^EXIM_USER.*$,EXIM_USER=exim,'           \
    -e '/# USE_OPENSSL/s,^#,,' src/EDITME > Local/Makefile &&

printf "USE_GDBM = yes\nDBMLIB = -lgdbm\n" >> Local/Makefile

sed -i '/# SUPPORT_PAM=yes/s,^#,,' Local/Makefile
echo "EXTRALIBS=-lpam" >> Local/Makefile

make

make install                                    &&
install -v -m644 doc/exim.8 /usr/share/man/man8 &&

install -vdm 755    /usr/share/doc/exim-4.98 &&
cp      -Rv doc/*   /usr/share/doc/exim-4.98 &&

ln -sfv exim /usr/sbin/sendmail                 &&
install -v -d -m750 -o exim -g exim /var/spool/exim

Command Explanations

sed -e ... > Local/Makefile: Most of Exim's configuration options are defined in Local/Makefile, which is created from the src/EDITME file. This command specifies the minimum set of options. Descriptions for the options are listed below.

printf ... > Local/Makefile: Setting those variables allows to use GDBM instead of the default Berkeley DB. Remove this command if you have installed Berkeley DB (deprecated).

BIN_DIRECTORY=/usr/sbin: This installs all of Exim's binaries and scripts in /usr/sbin.

CONFIGURE_FILE=/etc/exim.conf: This installs Exim's main configuration file in /etc.

EXIM_USER=exim: This tells Exim that after the daemon no longer needs root privileges, the process needs to hand off the daemon to the exim user.

USE_OPENSSL: uncommenting USE_OPENSSL=yes and USE_OPNSSL_PC=yes tells the build system to use OpenSSL, and to find the needed libraries with pkg-config.

Uncomment EXIM_MONITOR: This allows building the Exim monitor program, which requires X Window System support, and is commented out by default.

ln -sfv exim /usr/sbin/sendmail: Creates a link to sendmail for applications which need it. Exim will accept most Sendmail command-line options.

install -v -m750 -o exim -g exim /var/spool/exim: Since /var/spool is owned by root and this version of exim drops root privileges early, to run as user exim, it cannot create the /var/spool/exim directory. As a work around, it is created manually.

Adding Additional Functionality

To utilize some or all of the dependency packages, you'll need to modify Local/Makefile to include the appropriate directives and parameters to link additional libraries before you build Exim. Local/Makefile is heavily commented with instructions on how to do this. Listed below is additional information to help you link these dependency packages or add additional functionality.

If you wish to build and install the .info documentation, refer to https://exim.org/exim-html-4.98/doc/html/spec_html/ch04.html#SECTinsinfdoc.

If you wish to build in Exim's interfaces for calling virus and spam scanning software directly from access control lists, uncomment the WITH_CONTENT_SCAN=yes parameter and review the information found at https://exim.org/exim-html-4.98/doc/html/spec_html/ch45.html.

To use a backend database other than GDBM, see the instructions at https://exim.org/exim-html-4.98/doc/html/spec_html/ch04.html#SECTdb.

For SSL functionality, see the instructions at https://exim.org/exim-html-4.98/doc/html/spec_html/ch04.html#SECTinctlsssl and https://exim.org/exim-html-4.98/doc/html/spec_html/ch42.html.

For tcpwrappers functionality, see the instructions at https://exim.org/exim-html-4.98/doc/html/spec_html/ch04.html#SECID27.

For information about adding authentication mechanisms to the build, see chapters 33—41 of https://exim.org/exim-html-4.98/doc/html/spec_html/index.html.

For information about linking Linux-PAM, refer to the instructions https://exim.org/exim-html-4.98/doc/html/spec_html/ch11.html#SECTexpcond.

For information about linking database engine libraries used for Exim name lookups, see the instructions at https://exim.org/exim-html-4.98/doc/html/spec_html/ch09.html.

If you wish to add Readline support to Exim when invoked in “test expansion” (-be) mode, see the information in the -be section of https://exim.org/exim-html-4.98/doc/html/spec_html/ch05.html#id2525974.

You may wish to modify the default configuration and send log files to syslog instead of the default /var/spool/exim/log directory. See the information at https://exim.org/exim-html-4.98/doc/html/spec_html/ch-log_files.html.

A wealth of information can be also found at the Exim Wiki.

chmod -v a+wt /var/mail

cat >> /etc/aliases << "EOF"
postmaster: root
MAILER-DAEMON: root
EOF
/usr/sbin/exim -bd -q15m

cat > /etc/pam.d/exim << "EOF"
# Begin /etc/pam.d/exim

auth    include system-auth
account include system-account
session include system-session

# End /etc/pam.d/exim
EOF

make install-exim