iredmail-doc/store.spamassassin.bayes.in.sql.md

http://www.iredmail.org/wiki/index.php?title=IRedMail/FAQ/Store.SpamAssassin.Bayes.In.SQL #How to store spamassassin bayes in SQL

THIS ARTICLE IS STILL A DRAFT, DO NOT APPLY IT IN PRODUCTION SERVER.

##Summary This article is used to configure related components to store SpamAssassin Bayes data in SQL server, and allow webmail users to report spam with one click.

Tested with:

• iRedMail-0.8.0, iRedMail-0.8.7.
• CentOS 6.2 (x86_64)
• SpamAssassin-3.3.1
• Amavisd-new-2.6.6
• MySQL-5.1.61
• Roundcubemail-0.7.2

Notes:

• This article should work with all iRedMail releases. We take iRedMail-0.8.0 for example.
• This article should work with all backends: OpenLDAP, MySQL, PostgreSQL. We take MySQL backend for example.
• This article should work with Amavisd-new-2.6.0 and later versions, includes Amavisd-new-2.7.x.

IMPORTANT NOTE:

• The bayesian classifier can only score new messages if it already has 200 known spams and 200 known hams.
• If Spamassassin fails to identify a spam, teach it so it can do better next time. e.g. Mark it as spam in roundcube webmail.
• Read References section at the end of this article before asking.

##Create required SQL database used to store bayes data

We need to create a SQL database and necessary tables to store SpamAssassin bayes data. The RPM package installed on CentOS 6 doesn't ship SQL template for bayes database, but we can download it from Apache web site. We're running SpamAssassin-3.3.1, so what we need is this SQL template file: http://svn.apache.org/repos/asf/spamassassin/tags/spamassassin_release_3_3_1/sql/bayes_mysql.sql (if you're running different version, please find the proper SQL file here: http://svn.apache.org/repos/asf/spamassassin/tags/)

# cd /root/
# wget http://svn.apache.org/repos/asf/spamassassin/tags/spamassassin_release_3_3_1/sql/bayes_mysql.sql

Create MySQL database and import SQL template file:

# mysql -uroot -p
mysql> CREATE DATABASE sa_bayes;
mysql> USE sa_bayes;
mysql> SOURCE /root/bayes_mysql.sql;

Create a new MySQL user (with password sa_user_password) and grant permissions:

• Note: Please replace password sa_user_password by your own.

mysql> GRANT SELECT, INSERT, UPDATE, DELETE ON sa_bayes.* TO sa_user@localhost IDENTIFIED BY 'sa_user_password';
mysql> FLUSH PRIVILEGES;

##Enable Bayes modules in SpamAssassin

Edit /etc/mail/spamassassin/local.cf, add (or modify below settings):

use_bayes          1
bayes_auto_learn   1
bayes_auto_expire  1

# Store bayesian data in MySQL
bayes_store_module Mail::SpamAssassin::BayesStore::MySQL
bayes_sql_dsn      DBI:mysql:sa_bayes:127.0.0.1:3306

# Store bayesian data in PostgreSQL
#bayes_store_module Mail::SpamAssassin::BayesStore::PgSQL
#bayes_sql_dsn      DBI:Pg:sa_bayes:127.0.0.1:5432

bayes_sql_username sa_user
bayes_sql_password sa_user_password

# Override the username used for storing
# data in the database. This could be used to group users together to
# share bayesian filter data. You can also use this config option to
# trick sa-learn to learn data as a specific user.
bayes_sql_override_username vmail

Make sure SpamAssassin will load bayes modules:

# /etc/init.d/amavisd stop
# amavisd -c /etc/amavisd/amavisd.conf debug 2>&1 | grep -i 'bayes'
May 16 09:59:33 ... SpamAssassin loaded plugins: ..., Bayes, ...
May 16 10:27:38 ... extra modules loaded after daemonizing/chrooting:
    Mail/SpamAssassin/BayesStore/MySQL.pm, Mail/SpamAssassin/BayesStore/SQL.pm, ...

Looks fine. Now press 'Ctrl-C' to terminate above command.

Start Amavisd service:

# /etc/init.d/amavisd restart

It is required we initialize the database by learning a message. We use the sample spam email shipped in the RPM package provided by CentOS 6:

# rpm -ql spamassassin | grep 'sample-spam'
/usr/share/doc/spamassassin-3.3.1/sample-spam.txt

# sa-learn --spam --username=vmail /usr/share/doc/spamassassin-3.3.1/sample-spam.txt
Learned tokens from 1 message(s) (1 message(s) examined)

##Enable Roundcube plugin: markasjunk2

• We need a third-party Roundcube plugin to allow webmail users to report spam: Mark as Junk 2. You can download it here: https://github.com/JohnDoh/Roundcube-Plugin-Mark-as-Junk-2/releases

• After download, please uncompress it and copy it to roundcube plugins directory: /var/www/roundcubemail/plugins/. Then we get a new directory: /var/www/roundcubemail/plugins/markasjunk2/

• Enter directory /var/www/roundcubemail/plugins/markasjunk2/, generate config file by copying its sample config file:

# cd /var/www/roundcubemail/plugins/markasjunk2/
# cp config.inc.php.dist config.inc.php

• Edit roundcubemail/plugins/markasjunk2/config.inc.php, update below settings:

$rcmail_config['markasjunk2_learning_driver'] = 'cmd_learn';
$rcmail_config['markasjunk2_read_spam'] = true;
$rcmail_config['markasjunk2_unread_ham'] = false;
$rcmail_config['markasjunk2_move_spam'] = true;
$rcmail_config['markasjunk2_move_ham'] = true;
$rcmail_config['markasjunk2_mb_toolbar'] = true;


$rcmail_config['markasjunk2_spam_cmd'] = 'sa-learn --spam --username=vmail %f';
$rcmail_config['markasjunk2_ham_cmd'] = 'sa-learn --ham --username=vmail %f';

• Enable this plugin in Roundcube config file(/var/www/roundcubemail/config/main.inc.php) by appending 'markasjunk2' in plugin list:

$rcmail_config['plugins'] = array("password", "managesieve", "markasjunk2");

• Since learning driver cmd_learn requires PHP function exec, we have to enable it in /etc/php.ini:

# OLD SETTING
# disable_functions =show_source,system,shell_exec,passthru,exec,phpinfo,proc_open ;

# NEW SETTING. exec is removed.
disable_functions =show_source,system,shell_exec,passthru,phpinfo,proc_open ;

• Restarting Apache web server.

You will see a new toolbar button after logging into Roundcube webmail:

Check SQL database sa_bayes before we testing this plugin:

# mysql -uroot -p
mysql> USE sa_bayes;
mysql> SELECT COUNT(*) FROM bayes_token;
+----------+
| count(*) |
+----------+
|       65 |
+----------+

Back to Roundcube webmail, select a spam email (or a testing email), click "Mark as Junk" button, then this email will be scanned by command sa-learn. Check database sa_bayes again to make sure it's working:

# mysql -uroot -p
mysql> USE sa_bayes;
mysql> SELECT COUNT(*) FROM bayes_token;
+----------+
| count(*) |
+----------+
|      143 |
+----------+

Note: You may get different result number as shown above.
So far so good. That's all we need to do. ##References

• Bayes Introduction. Please do read section Things to remember.
• SpamAssassin Bayes Frequently Asked Questions