bzrtp (ZRTP Key Exchange Library)

bzrtp is an opensource implementation of the ZRTP key exchange
protocol.

The library written in C89 is fully portable and can be executed on
many platforms including both ARM processors and x86.

Licensing: The source code is licensed under GPLv2.

Compatibility with RFC6189 (ZRTP: Media Path Key Agreement for Unicast
Secure RTP):

*** Mandatory but NOT implemented:
- Sas Relay mechanism (section 7.3)
- Error message generation, emission or reception (which doesn't imply
  any security problem, they are mostly for debug purposes)

*** Optional and implemented:
- multistream mode
- cacheless implementation
- key agreement DH2048

*** Optional and NOT implemented:
- zrtp-hash attribute in SDP
- Go Clear/Clear ACK messages
- SAS signing