SSMTP

Created Friday 13 January 2017

SSMTP is a program that can deliver E-mails from our local computer.

Installation

$ pacman -S ssmtp

Configuration

# This is setup to deliver mails to my private domain mail (info@sloa.dk)
# For obvious reasons, the password has been left out
# Corrected this, then override the default /etc/ssmtp/ssmtp.conf with the following

# The user that gets all the mails (UID < 1000, usually the admin)
root=info@sloa.dk

# The mail server (where the mail is sent to), both port 465 or 587 should be acceptable
# See also https://support.google.com/mail/answer/78799
mailhub=asmtp.unoeuro.com:587

# The address where the mail appears to come from for user authentication.
rewriteDomain=unoeuro.com

# The full hostname
hostname=dinnabo

# Use SSL/TLS before starting negotiation
UseTLS=Yes
UseSTARTTLS=Yes

# Username/Password
AuthUser=info@sloa.dk
AuthPass=
AuthMethod=LOGIN

# Email 'From header's can override the default domain?
FromLineOverride=yes

# Having passwords in plaintext is insecure - so we'll secure the newly edited ssmtp.conf file
# Create a ssmtp group
$ groupadd ssmtp

# Set the newly created group as owner of the ssmtp.conf file
$ chown :ssmtp /etc/ssmtp/ssmtp.conf

# Set the newly created group as owner of the ssmtp binary
$ chown :ssmtp /usr/bin/ssmtp

# Limit access to just root and ssmtp
$ chmod 640 /etc/ssmtp/ssmtp.conf

# And set the SGID on the ssmtp binary
$ chmod g+s /usr/bin/ssmtp

Usage

# Test if everything works
$ echo "this is the body" | mail -s "Subject" jeppesen@tutanota.com

# You can also send mails by creating a empty text file and providing it to the mail function.
# Here's a template; ~/test-mail.txt

To:jeppesen@tutanota.com
From:info@sloa.dk
Subject: Test

This is a test mail.

# Then provide the text-file to the mail function
$ mail jeppesen@tutanota.com < ~/test-mail.txt