sipscreen is a Linux iptables QUEUE target handler written in perl for screening incoming SIP phone calls. If you have a network configuration similar to mine, with a Vonage or other Voice-over-IP adapter located behind a Linux gateway, you may find sipscreen useful for programmatically accepting or rejecting inbound calls, based on the caller ID information, the time of day, or any other clever algorithm you can think of.

For more information, see the POD information contained in the sipscreen-ipqueue. file, and the sample sipscreen-decider.sample program included in the distribution.

For more information about writing ipqueue target handlers in perl, see the slides from the talk I gave to the Philadelphia Perl Mongers in 2003. You may also be interested in countertrace, another ipqueue target handler for faking traceroutes.

sipscreen is free software, distributed under the terms of the GPL.

• sipscreen-1.00.tar.gz, released 2007-06-09
• MD5 checksums, clearsigned with GPG.
• svn repository, also available at svn://svn.netisland.net/sipscreen/

Questions? Comments? Reports of successful installations? Let me know.