There is an open GSM client stack in OsmocomBB: http://bb.osmocom.org/trac/wiki/Software/GettingStarted http://bb.osmocom.org/trac/wiki/Software/GettingStarted

There is an open GSM client stack in OsmocomBB: http://bb.osmocom.org/trac/wiki/Software/GettingStarted http://bb.osmocom.org/trac/wiki/Software/GettingStarted It only works with certain baseband chips though, but has already been used to crack the A5/1 GSM crypto: http://www.youtube.com/watch?v=ZrbatnnRxFc http://www.youtube.com/watch?v=ZrbatnnRxFc Many of the other things you mention can already be done by using off the shelf GSM baseband chips, since they don't necessarily do much access control of what gets sent.