Using the RelayCountry plugin
The \[http://spamassassin.apache.org/full/3.0.x/dist/doc/Mail_SpamAssassin_Plugin_RelayCountry.html RelayCountry\] plugin exposes the countries that a mail was relayed from -- – turn it on by reading that documentation page, installing the required CPAN module {{ Wiki Markup IP::Country::Fast
}}, and uncommenting the 'loadplugin' line in the {{/etc/mail/spamassassin/init.pre
}} file for {{Mail::SpamAssassin::Plugin::RelayCountry
}}.
The \[http://spamassassin.apache.org/full/3.0.x/dist/doc/Mail_SpamAssassin_Plugin_RelayCountry.html RelayCountry\] plugin will add metadata to the Bayesian filtering process, allowing the Bayesian filters to learn information based on countries. Wiki Markup
When using SA 3.1.0, you can also write rules that match specific countries and add them to your /etc/mail/spamassassin/local.cf
file. For example:
No Format |
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header RELAYCOUNTRY_CN X-Relay-Countries =~ /CN/ describe RELAYCOUNTRY_CN Relayed through China score RELAYCOUNTRY_CN 3.0 header RELAYCOUNTRY_RU X-Relay-Countries =~ /RU/ describe RELAYCOUNTRY_RU Relayed through Russian Federation score RELAYCOUNTRY_RU 2.0 |
You can get a list of IANA country codes from \[http://www.iana.org/cctld/cctld-whois.htm\]. You can get a list of countries that statistically relay most of the spam by looking at the source file for \from SpamAssassin::EvalTests.pm]. You can get a list of countries that statistically relay most of the spam by looking at the source file for [http://svn.apache.org/repos/asf/spamassassin/branches/3.1/lib/Mail/SpamAssassin/EvalTests.pm SpamAssassin::EvalTests.pm\] and reading the comments surrounding {{ Wiki Markup $CCTLDS_WITH_LOTS_OF_OPEN_RELAYS
}}.
Also for 3.1.0, you can apply a patch \[http://bugzilla.spamassassin.org/show_bug.cgi?id=3815\] which will allow you to add a separate MIME header that shows all the message's relay countries, independent of the rules. Wiki Markup
No Format |
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add_header all Relay-Country _RELAYCOUNTRY_ |
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