Hi,
We're interested in getting GTP protocol [1,2] support into OpenBSD's
tcpdump, however there doesn't appear to be any upstream support for
it [0].
So, if any of the devs are interested in paid work to add this then
please drop me a line. This would ideally be someone with CVS write
access, so that we're supporting the project more directly.
Ethereal/wireshark, already has some support [4] so that could be of
assistance, but appears to be GPL.
The official protocol specs are freely available from [3]
[0] http://github.com/mcr/tcpdump/tree/master
[1] http://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol
[2] http://en.wikipedia.org/wiki/GTP%27
[3] http://www.3gpp.org/ftp/Specs/
[4] http://anonsvn.wireshark.org/wireshark/trunk/epan/dissectors/packet-gtp.c
/Pete
