Amavis

Amavis is a virus scanner for e-mail services.

Installation

Aptitude command:

 aptitude install amavis

Configuration

Open file:

 nano /etc/amavis/conf.d/15-content_filter_mode

and remove number sign (#) from the lines:

@bypass_virus_checks_maps = (
  \%bypass_virus_checks, \@bypass_virus_checks_acl, \$bypass_virus_checks_re);

and

@bypass_spam_checks_maps = (
  \%bypass_spam_checks, \@bypass_spam_checks_acl, \$bypass_spam_checks_re);

Restart service

 service amavis restart

Postfix integration

Open the Postfix configuration file

 nano /etc/postfix/main.cf

Add the following line in the file:

 content_filter = smtp-amavis:[127.0.0.1]:10024

Open another Popstfix configuration file master.cf:

 nano /etc/postfix/master.cf

Add the following snip to the end of the file:

 smtp-amavis     unix    -       -       -       -       2       smtp
       -o smtp_data_done_timeout=1200
       -o smtp_send_xforward_command=yes
       -o disable_dns_lookups=yes
       -o max_use=20

127.0.0.1:10025 inet    n       -       -       -       -       smtpd
       -o content_filter=
       -o local_recipient_maps=
       -o relay_recipient_maps=
       -o smtpd_restriction_classes=
       -o smtpd_delay_reject=no
       -o smtpd_client_restrictions=permit_mynetworks,reject
       -o smtpd_helo_restrictions=
       -o smtpd_sender_restrictions=
       -o smtpd_recipient_restrictions=permit_mynetworks,reject
       -o smtpd_data_restrictions=reject_unauth_pipelining
       -o smtpd_end_of_data_restrictions=
       -o mynetworks=127.0.0.0/8
       -o smtpd_error_sleep_time=0
       -o smtpd_soft_error_limit=1001
       -o smtpd_hard_error_limit=1000
       -o smtpd_client_connection_count_limit=0
       -o smtpd_client_connection_rate_limit=0
       -o receive_override_options=no_header_body_checks,no_unknown_recipient_checks

Add this to the same file in the "pickup" section:

   -o content_filter=
   -o receive_override_options=no_header_body_checks

Reload postfix

 sudo /etc/init.d/postfix reload

Sources

https://help.ubuntu.com/community/PostfixAmavisNew