[Linphone-users] Incorrect m=video media-field in 200 OK SDP

[Ivan Khvatov]

Hello all.

Linphone 3.4.2 in audio mode sends incorrect SDP message on incoming 
video-calls. Specially, video media-field does not match the RFC4566 grammar.

Part of SDP message in 200 OK message from Linphone (full trace see in debug 
logs in footer of this email):
"""
m=video 0 RTP/AVP
a=inactive
"""

media-field grammar:
"""
media-field =         %x6d "=" media SP port ["/" integer]
                      SP proto 1*(SP fmt) CRLF
"""

i.e.: m=<media> <port> <proto> <fmt> ...

So, at least one "fmt" field is required. By the way, older Linphone (3.3.2) 
does not put m=video in this case. Linphone 3.4.2 and 3.3.2 uses same version 
of eXosip2 library (according User-Agent header version is 3.3.0).


How to reproduce:
1. Switch Linphone to "Audio only" mode.
2. Make video call to Linphone.
3. Answer call on Linphone.


Actual results:
Call establishing fails. Remote party did not understand SDP in 200 OK reply 
and drop call.


Expected results:
Successfully established audio call.


Linphone version: 3.4.2
Linphone 3.3.2 works fine.


Debug logs:

Linphone 3.4.2 debug log (from startup to test call, call failed):
http://dev.sgu.ru/pub/linphone-3.4.2-audio-only.log

Linphone 3.3.2 debug log (from startup to test call, successful call):
http://dev.sgu.ru/pub/linphone-3.3.2-audio-only.log

I hope that this is right mailing list for this report. If not, let me know.

-- 
WBR, Ivan Khvatov