date: 08/21/2008

This HowTo describes the setup of a Gentoo based spam and virus filtering mailgateway. This server is meant to run in front of the servers keeping the mail accounts i.e. Zarafa, Lotus Notes or Microsoft Exchange.
The MTA is postfix which will listen on port 25 for inbound mail. Recieved mails are forwarded to amavisd-new on port 10024. Amavisd-new filters the mail for virii and spam before passing it back to Postfix on port 10025 for final delivery.
In this Setup ClamAV is used for virusscans, if a virus is found the mail is discarded or optional quarantined, if no virus is found the mail first runs through dspam and afterwards through Spamassassin for antispam. dspam gets better detection rates than SpamAssassin's Bayes filter, it writes it's headers which will then be scored by SpamAssassin together with some other tests.

HAVP (HTTP AntiVirus proxy) is a proxy with an anti-virus filter. It does not cache or filter content, but is scanning the complete http traffic for viruses or malicious content. It's amining to stop dialers or browser exploits and features Continuous and non-blocking downloads, Smooth scanning of dynamic and password protected homepages

I've got a PC Engines WRAP.1E and a 32mb compact flash card, and I wanted Gentoo on it to be used and abused as a home router / firewall appliance. For this purpose some nice projects are available, like Gentoo Network Appliance (GNAP) for example. An other nice project is Soentoo although it's aiming for Soekris boards it works on WRAP since the hardware is similar. If you want the benefit of a nice webgui for your router check out M0n0wall or pfSense both FreeBSD based firewall distributions. First I started using the WRAP with M0n0wall but I don't need the webgui and the other solutions available didn't satisfy me.