The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements auto-whitelists, self learning Bayesian, Greylisting, DNSBL, DNSWL, URIBL, SPF, SRS, Backscatter, Virus scanning, attachment blocking, Senderbase and multiple other filter methods. Click 'Browse all files' to download the professional version 2.4.1 build 14200.
V1 development has been stopped in May 2014. Possibly there will be done some bugfixing until end of 2014.
EOL of V1 is anounced for the 31 December 2014.
Please upgrade to V2, which is and will be actively maintained.
- Multiple Weighted DNSBLs
- Multiple Weighted URIBLs
- Weighted Regular Expression Filtering
- Penalty Box
- Attachment Blocking
- ClamAV and FileScan
- Blocking Reporting
- LDAP support
- Backscatter Detection
- V2 - recipient replacement / GUI user access rights management
- V2 - MIME charset conversion / DKIM check and signing
- V2 - DB support for all hashes / level based open plugin support
- V2 - transparent proxy support / BATV check and signing
- V2 - Plugins: archive, full attachment check and replacement, OCR
- V2 - damping (steal spammers time)
- V2 - AUTH to relay host / POP3 collector
- V2 - configuration value and file synchronization
- V2 - Block Reports design could be customized
- V2 - Razor2 and DCC support via Plugin
- V2 - SNMP support (monitoring, configuring, controll-API)
- V2 - user group import (file or LDAP or command based)
- V2 - automatic crash analyzer Hidden Markov Model
- V2 - IPv6 socket support
- V2 - word stemming (several languages) for Bayesian analyzer
- V2 - Perl module autoupdate via PPM or CPAN
- V2 - Hidden Markov Model spam detection engine
- V2 - full unicode support
- V2 - DMARC support
- V2 - privat Whitelist (legacy, domain based, user based)
- V2 - privat IP and Domain lists (legacy, domain based, user based)
- V2 - CPU affinity settings
- V2 - web file commander
- V2 - graphical statistic output (SVG)
- V2 - native SSL support for target hosts
- V2 - client SSL-certificate validation
Insanely hard to configure, no helpfull tutorial available what can be a good start, but its worth a try for sure.