[Freeswitch-users] Accepting an "optional" SRTP offer (crypto in RTP/AVP) and establishing SRTP

[William Simon]

We are working with an endpoint that offers optional SRTP in the non-RFC-compliant way of an a=crypto attribute within RTP/AVP.

I have told FreeSWITCH to allow this with rtp_allow_crypto_in_avp=true at the right place in the dialplan.

Immediately after that in the dialplan I have to reject SRTP by using rtp_secure_media=forbidden, otherwise the call setup still fails. By setting the value to forbidden, the call does proceed unencrypted.

We want FreeSWITCH to proceed with media encryption. Setting rtp_secure_media to any other value results in FreeSWITCH rejecting the offer like this:

v=0
o=FreeSWITCH 1538660754 1538660755 IN IP4 192.168.100.104
s=FreeSWITCH
c=IN IP4 192.168.100.104
t=0 0
m=audio 0 RTP/AVP 19
m=video 0 RTP/AVP 19

Is there anything else I can do to force SRTP in the answer?







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