MIMEDefang Filter (and more)

Additions | Notes | Files | GNU GPL

The perl stuff below is the filter we're currently using with MIMEDefang in the hope that we'll get less spam, and some other stuff used together with the filter.

If you use MIMEDefang yourself, this filter will show you how to do some more advanced stuff that's not in the distributions example filter.

Important:

This stuff is done using perl. It's not a simple configuration file. This is the main power of MIMEDefang. You loose simplicity but gain flexibility.

If you don't feel comfortable editing perl code for something as important as a mail server, you're probably better of with CanIt from Roaring Penguin or SPAM-P from Tadcom AB.

Main additions

• A flexible selective greylist implementation.
• A simple dictionary attack resource-saver scheme.
• A relaydb-inspired automagic blacklisting scheme.
• Checking of received lines.
• Simple regular expression based black and white lists.
• Checking mismatching file types/extensions.
• Some simple (dirty) header "cleaning".
• Moderate HTML cleansing.
• Result querying/reporting.
• Boilerplate config.
• Verification of DomainKey, DKIM, SPF and PGP.
• SpamAssassin bypassing based on verified senders.
• SpamAssassin bypassing based on previous mails.
• SpamAssassin plugins that uses info from the same database as the filter.
• Automatgic whitelist.
• Caching MX and address checks.
• SMTP EXPN forward check.
• Caching of virus scan results.
• SRS envelope rewriting.
• A spam trapper and reporter.
• A web based quarantine tool.

Possible future additions?

• Split the monster into multiple modules/files...

Notes

• Do read the comments for the different settings before using this code straight off!
• Actually, read through the whole file before using any of it.
• Understand what the code actually does before you use it.
• The code may contain errors (though it is code we use on our mail gateway handling all our mail). I'm probably not doing everything in the most efficient way.
• If you use any of the stuff that uses the SQL database, you also need the little cleaner/creator for the SQL database.
• If you use SpamAssassin you might also like our SpamAssassin stuff, including the SentOutDB, DictionaryCheckDB and RepeatMessageDB plugins.
• If you like the p0f headers in this filter, you might want to use my p0f stuff as well.

Files

• The configuration (view)
• The filter (view)
• A log handler (view)
• SQL Database Cleaner/Creator (view)
• SQL Database Info Lister (view)
• A Reporter (view)
• A Mail Reporter (view)
• A Quarantine Tool (view)
• SentOutDB.pm (view)
• DictionaryCheckDB.pm (view)
• RepeatMessageDB.pm (view)

Regards
/Jonas EckermanDon't send mail to trammer@frukt.org.

(2009-01-28)