Mason is a Linux based firewall, but none like you've ever used. In short, you put Mason into learning mode and run the services to the Internet you wish to support. Mason will then take these log entries and turn them into a set of packet filtering rules. Pretty cool eh? No ACK compliment rules to worry about, no "what was that service port again?" decisions to worry about, simply plug it in, let it learn and off you go. :)". Mason is a tool that interactively builds a firewall using Linux' ipfwadm or ipchains firewalling. You leave mason running on the firewall machine while you are making all the kinds of connections that you want the firewall to support (and want it to block). Mason gives you a list of firewall rules that exactly allow and block those connections. Developer's release. Official Site: here.
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