spmfilter is a high-performance interface between mailer (MTA) and custom plugins, written in C. It provides a mail filtering framework and attemps to be a general framework for any purpose. Filtering mechanisms are provided by plugins, the API enables spmfilter plugins to access messages as they are being processed by the MTA. This allows them to examine and modify message content and meta-information during the SMTP transaction. Plugins are loaded at runtime and can be processed in any sequence, the processing chain can also be altered by a single plugin, for example if the plugin has to stop further processing (e.g. the clamav-plugin detected malicious software like a virus and the infected message is actually discarded - so further processing is stopped by the plugin).
You can download the sources at http://spmfilter.org/files
Development is done using Git
Follow these links to find available documentation and installation notes:
There are two mailing lists devoted to spmfilter.
If you believe you have found a bug, please send this information, plus information about the machine and OS platform used along with a description of the problem to bugs@.firstname.lastname@example.org@m.ilter.nosp@m..org
We're happy about developers who want to share their usefull spmfilter-plugins with the community. Just contact us on the developers mailing list if you want to contribute spmfilter-plugins to spmfilter.
spmfilter is released under the LGPL . This means (in short..) that you are free to use, change and distribute it.