This article shows how to make an Slackware machine your personal Mail Server. This howto is for Slackware 64 13.37, but with few changes you can adapt it to the newest member of Slackware familly Slackware 14.

Before we begin I must say that you need a normal installation of Slackware, without any special packages. The packages we will need to make the Mail Server we will manually download and install from Slackbuilds.org. I preffer the Cyrus SASL authentication method and Cyrus IMAP for remote login, insted of other alternatives like qpopper or dovecot.

Let's get started then , we will need to install Cyrus-SASL, Postfix, Cyurs-IMAP and then configure them all to use Certificates for encrypting the mail packages that traverse the Internet.

# cd /tmp
# mkdir cyrus-sal
# cd cyrus-sasl
# wget ftp://ftp.slackware.com/pub/slackware/slackware64-13.37/source/n/cyrus-sasl/cyrus-sasl-2.1.23.tar.xz
# wget ftp://ftp.slackware.com/pub/slackware/slackware64-13.37/source/n/cyrus-sasl/cyrus-sasl.SlackBuild
# wget ftp://ftp.slackware.com/pub/slackware/slackware64-13.37/source/n/cyrus-sasl/doinst.sh.gz
# wget ftp://ftp.slackware.com/pub/slackware/slackware64-13.37/source/n/cyrus-sasl/rc.saslauthd.gz
# wget ftp://ftp.slackware.com/pub/slackware/slackware64-13.37/source/n/cyrus-sasl/slack-desc

# joe cyrus-sasl.SlackBuild

and add the following lines after “–disable static”

--enable-plain \
--disable-digest \

# sh cyrus-sasl.SlackBuild
# installpkg /tmp/cyrus-sasl-2.1.23-x86_64-1.txz

# cd /tmp
# mkdir postfix
# cd postfix
# wget http://postfix.cs.utah.edu/source/official/postfix-2.8.3.tar.gz
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/README
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/doinst.sh
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/postfix.SlackBuild
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/postfix.info
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/rc.postfix
# wget http://slackbuilds.org/slackbuilds/13.37/network/postfix/slack-desc

# joe postfix.Slackbuild

Edit the following line and replace “dovecot” with “cyrus” like this

SASL=${SASL:-cyrus}

In order to begin Postfix installation you will need to create postfix user and group (also keep in mind that we need to add user postfix and user cyrus to the same group, mail group that is).

# groupadd -g 200 postfix
# useradd -u 200 -d /dev/null -s /bin/false -g postfix postfix -G mail
# groupadd -g 201 postdrop
# sh postfix.SlackBuild  
# installpkg /tmp/postfix-2.8.3-x86_64-1_SBo.tgz 

Before we continue with installation of Imap server we need to assure that Postfix is working and we can authenticate with sasl. Let's make some basic Postfix configuration and some basic SASL configuration. I will be explaining plain auth because later on we will use it togheter with sasl to authenticate.

First of all we need to make our aliases and tell postfix to use aliases maps from /etc/postfix/aliases, so :

# joe /etc/postfix/main.cf

Edit these lines and make them look like this :

alias_maps = hash:/etc/postfix/aliases
alias_database = hash:/etc/postfix/aliases  

Now let's add a user to the Slackware machine, a user who will also can read and send mail.

# adduser

Login name for new user []:xxxxxx
User ID ('UID') [ defaults to next available ]: press ENTER
Initial group [ users ]: 200
Home directory [ /home/xxxxxx ]: press ENTER
Shell [ /bin/bash ]: /bin/false
Do you wish to change the sheel? (Y/n): n
Expiry date (YYYY-MM-DD) []: press ENTER
Press ENTER and imput full name and other account relates stuff. Also specify an password for your newly created user.

Now edit /etc/postfix/aliases and modifiy it to your needs :

root:           your_user
office:	  your_user, your_next_user

Now update your aliases database issuing the command :

# postalias hash:/etc/postfix/aliases   

It is now time to make our important configurations for Postfix in order for it to run.

# joe /etc/postfix/main.cf
myhostname = mx.yourdomain.tld
mydomain = yourdomain.tld 
myorigin = $mydomain
inet_interfaces = all
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
mynetworks = 127.0.0.0/8

Let's now configure Postfix to authenticate users using SASL

# mkdir /etc/sasl2
# cd /etc/sasl2
# touch smtpd.conf
# joe smtpd.conf 

pwcheck_method: saslauthd
mech_list: PLAIN LOGIN

Now let's configure Postfix to have users authenticate using SASL. Edit /etc/postfix/main.cf and add the folowing code to the end of the file :

smtpd_sasl_auth_enable = yes   
broken_sasl_auth_clients = yes  
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination

Let's start the daemons and test our configurations until now:

# saslauthd -a shadow
# postfix start

Then from another machine telnet into your mail server on port 25 and issue the following commands :

# telnet mx.mailserver.com 25
ehlo user.mailserver.tld   
250-mx.mailserver.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-AUTH PLAIN LOGIN
250-AUTH=PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
AUTH PLAIN Y4R0QYxpcuHsFBRbbGjnPHIwYjB0MWrpMTk7La==
235 2.7.0 Authentication successful
MAIL FROM: <user@mailserver.com>
250 2.1.0 Ok
RCPT TO: <user@yahoo.com>
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
HI. This mail is a test .
.
250 2.0.0 Ok: queued as 4C0EE221E93
QUIT