Originally released in May of 2002, SpamPD is a program used within an e-mail delivery system to scan messages for possible Unsolicited Commercial E-mail (UCE, aka spam) content. It uses an excellent program called SpamAssassin (SA) to do the actual message scanning. SpamPD acts as a transparent SMTP/LMTP proxy between two mail servers, and during the transaction it passes the mail through SA. If SA decides the mail could be spam, then SpamPD will ask SA to add some headers and a report to the message indicating it's spam and why.
SpamPD is written in Perl and should theoretically run on any platform supported by Perl and SpamAssassin.
Here's an un-solicited comment someone sent regarding SpamPD performance:
Just to let you know: We have the SA/spampd combo up an running in a high volume environment. With 3 KAT-B Server (4x 2,5 GHz Xeon MP with Hyperthreading, 3 GB RAM) we handle 15.000 to 20.000 Mails/h (Hour!) with room to spare. We had some performance issues with the Bayes databases but now everything runs smoothly.
Check the Releases area for latest versions,
and see the "previous-versions" folder for some more ancient ones.
(Note that the Debian package version was added to this repo as a branch, and those tags will also show up in the Releases page.)
Please read the POD file for full documentation of the many available options. See the changelog for full version history.
HELP! Debian package maintainer needed. Please see GitHub Issue 46.
Linux packages data at right courtesy of Repology:
SpamPD was initially designed as a content filter mechanism for use with the Postfix MTA. However, it has no inherent dependencies on Postfix or any other MTA. Some more specific setup information is provided in the included documentation.
Version 2 of SpamPD is a major rewrite of the underlying methods. SpamPD no longer acts as a relay server but more as a "transparent" proxy server. That is, it never actually takes responsibility for the mail at any point. Instead, the origination and destination mail servers speak directly to each other. If a failure occurs within SpamPD (or SpamAssassin) during a transaction, then the mail servers will disconnect and the sending server is still responsible for retrying the message for as long as it is configured to do so. Responsibility for mail delivery always lies with the 2 mail servers, which would be "real" MTAs and not a 500 line Perl script :-) This removes a major problem with version 1 of SpamPD, and makes this a recommended upgrade.
While this is a much safer technique than previously employed, it does remove a possible feature which some users of SpamPD have implemented (sorry guys). That is redirecting spam to a spamtrap address instead of letting the message through to the original recipient. This is due to the fact that the recipient information is passed on to the destination server before the message data is scanned for spam. On the other hand it presents the possibility of rejecting spam at the S/LMTP level without having to generate bounce notices and such.
SpamPD now fully supports the LMTP
protocol (due to the nature of it's new transparency). Logging has been
improved and is now more compatible with spamd.
New parameters added: --children, --local-only, --childtimeout,
--satimeout, --dose, --log-rules-hit, --add-sc-header, and --hostname.
Three parameters are now deprecated: --dead-letters, --heloname, and
--stop-at-threshold.
More details and further changes are documented in the change log.
If you aren't familiar with SpamAssassin, then you should definitely start there (or end up there) first. There is a very helpful users discussion list for SA (see their site). For Postfix setup, be sure to read the FILTER_README document that is included with the distribution. SpamPD is meant to be used as an "advanced content filtering" method (some examples are included with the SpamPD documentation). Postfix also has a helpful users discussion list. Make sure you do your homework before you ask other people to help you!
Be sure to check out the SpamPD documentation, the change log, as well as comments in the actual code.
SpamPD is written and maintained by Maxim Paperno (https://github.com/mpaperno).
SpamPD contains code written by
Bennecode Todd (Copyright (C) 2001 Morgan Stanley Dean Witter) and is used
in accordance with the GNU General Public License. The code is in the
form of two Perl modules which have been included in the program. Also
his smtpproxy example program served as inspiration for this version of SpamPD.
SpamPD version 1 was based on code by Dave Carrigan named assassind. Trace amounts of his code or documentation may still remain. Thanks to him for the original inspiration and code.
Various people have contributed patches, bug reports, and ideas, all of whom I would like to thank. I have tried to include credits in code comments, documentation, and in the change log, as appropriate.
Copyright Maxim Paperno; All rights reserved.
Portions are Copyright © 2001 Morgan Stanley Dean Witter as mentioned above in the CREDITS section.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
The GNU GPL can be found at https://www.gnu.org/licenses/