Replacing antispam plugin with IMAPSieve
========================================

Contents


 1. Replacing antispam plugin with IMAPSieve

     1. Caveats and possible pitfalls

     2. Dovecot configuration

     3. Sieve scripts

     4. Shell scripts

         1. For spamassassin

         2. For rspamd

     5. Debugging

You will need at least pigeonhole v0.4.14 for this. If you have already
configured sieve, please adjust the following to match your setup.

Caveats and possible pitfalls
-----------------------------

 * INBOX name is case-sensitive
 * <IMAP Sieve> [Pigeonhole.Sieve.Plugins.IMAPSieve.txt] will *only* apply to
   IMAP. It *will not* apply to LDA or LMTP. Use <Sieve> [Pigeonhole.Sieve.txt]
   normally for LDA/LMTP.
 * With this configuration, moving mails will slow down due to learn being done
   per email. If you want to avoid this, you need to think of something else.
   Probably piping things into a FIFO or perhaps using a socket based worker
   might work better.
 * Please read <Pigeonhole.Sieve.txt> and <Pigeonhole.Sieve.Configuration.txt>
   to understand sieve configuration better.
 * Please read <Pigeonhole.Sieve.Plugins.txt> for more information about sieve
   extensions.

Changes:

 * 2017/04/01 - Pass imap user to scripts.
 * 2017/03/19 - Added rspamd scripts and mention about sieve plugins.
 * 2017/02/13 - Improved documentation and added instructions for Spam->Trash.
   (Thanks for everyone who commented on mailing list)
 * 2017/02/10 - Removed imap_stats (it's not needed).

Dovecot configuration
---------------------

---%<-------------------------------------------------------------------------
protocol imap {
  mail_plugins = $mail_plugins imap_sieve
}

plugin {
  sieve_plugins = sieve_imapsieve sieve_extprograms

  # From elsewhere to Spam folder
  imapsieve_mailbox1_name = Spam
  imapsieve_mailbox1_causes = COPY
  imapsieve_mailbox1_before = file:/usr/lib/dovecot/sieve/report-spam.sieve

  # From Spam folder to elsewhere
  imapsieve_mailbox2_name = *
  imapsieve_mailbox2_from = Spam
  imapsieve_mailbox2_causes = COPY
  imapsieve_mailbox2_before = file:/usr/lib/dovecot/sieve/report-ham.sieve

  sieve_pipe_bin_dir = /usr/lib/dovecot/sieve

  sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.execute
}
---%<-------------------------------------------------------------------------

Sieve scripts
-------------

Create directory /usr/lib/dovecot/sieve and put following files to that:

report-spam.sieve

---%<-------------------------------------------------------------------------
require ["vnd.dovecot.pipe", "copy", "imapsieve", "environment", "variables"];

if environment :matches "imap.user" "*" {
  set "username" "${1}";
}

pipe :copy "sa-learn-spam.sh" [ "${username}" ];
---%<-------------------------------------------------------------------------

report-ham.sieve

---%<-------------------------------------------------------------------------
require ["vnd.dovecot.pipe", "copy", "imapsieve", "environment", "variables"];

if environment :matches "imap.mailbox" "*" {
  set "mailbox" "${1}";
}

if string "${mailbox}" "Trash" {
  stop;
}

if environment :matches "imap.user" "*" {
  set "username" "${1}";
}

pipe :copy "sa-learn-ham.sh" [ "${username}" ];
---%<-------------------------------------------------------------------------

Shell scripts
-------------

For spamassassin
----------------

sa-learn-spam.sh

---%<-------------------------------------------------------------------------
exec /usr/bin/sa-learn -u ${1} --spam
---%<-------------------------------------------------------------------------

sa-learn-ham.sh

---%<-------------------------------------------------------------------------
exec /usr/bin/sa-learn -u ${1} --ham
---%<-------------------------------------------------------------------------

For rspamd
----------

By default, rspamd does global learning. If you want per-user classification,
or something more complex, see
https://rspamd.com/doc/configuration/statistic.html

sa-learn-spam.sh

---%<-------------------------------------------------------------------------
exec /usr/bin/rspamc -h /run/rspamd/worker-controller.socket -P <secret>
learn_spam
---%<-------------------------------------------------------------------------

sa-learn-ham.sh

---%<-------------------------------------------------------------------------
exec /usr/bin/rspamc -h /run/rspamd/worker-controller.socket -P <secret>
learn_ham
---%<-------------------------------------------------------------------------

Before running following commands, make sure dovecot.conf has all the sieve
configuration you want. Then run following commands:

---%<-------------------------------------------------------------------------
sievec /usr/lib/dovecot/sieve/report-spam.sieve
sievec /usr/lib/dovecot/sieve/report-ham.sieve
chmod +x /usr/lib/dovecot/sieve/sa-learn-ham.sh
/usr/lib/dovecot/sieve/sa-learn-spam.sh
---%<-------------------------------------------------------------------------

Now your learn scripts should be invoked when you move mails between folders.

Debugging
---------

To debug, you need to import "vnd.dovecot.debug" extension. Then you can put,
when required

---%<-------------------------------------------------------------------------
debug_log "something"
---%<-------------------------------------------------------------------------

variables are supported in this.

(This file was created from the wiki on 2017-05-11 04:42)