Support a 3pcc INVITE without SDP-body

Submitted by Stefan Siegl

Assigned to Mikhail Zabaluev

Link to original bug (#32808)

Description

Hello,

I'm trying to connect my Nokia N900 to an Auerswald COMpact 5020 VoIP PBX, registration & outgoing calls work like a charm, but I've got a problem with incoming calls.

The PBX provides INVITEs without an SDP-body to the phone, which in turn answers 100 & 180 (ringing). If I click the accept-button the phone sends a 480:

--- LOG excerpt --- (telepathy-sofiasip:32602): tpsip-DEBUG: _tpsip_media_channel_add_member: accepting an incoming invite (telepathy-sofiasip:32602): tpsip-DEBUG: tpsip_media_session_debug: SIP media session [invite-received ]: accepting the session (telepathy-sofiasip:32602): tpsip-WARNING **: priv_session_respond: cannot respond with a valid SDP answer, were all streams closed? (telepathy-sofiasip:32602): tpsip-DEBUG: priv_session_rollback: enter (telepathy-sofiasip:32602): tpsip-DEBUG: tpsip_media_session_terminate: enter (telepathy-sofiasip:32602): tpsip-DEBUG: tpsip_media_session_terminate: sending the 480 response to an incoming INVITE --- full log at: http://paste.q0a.de/m3562

... instead of that I'd expect it to reply a 200 with SDP-answer, but I can't figure out how to get tp-sofiasip to do that for me :-)

I've tried several variations of ...

  user_sdp = g_string_append (user_sdp, "m=audio 0 RTP/AVP 0\r\n");
  nua_respond (priv->nua_op, SIP_200_OK,
               SOATAG_USER_SDP_STR (user_sdp->str),
               SOATAG_RTP_SORT(SOA_RTP_SORT_REMOTE),
               SOATAG_RTP_SELECT(SOA_RTP_SELECT_ALL),
               NUTAG_AUTOANSWER(0),
               TAG_END());

... and the like in the else-part of priv_session_respond, but that doesn't help much. Session negotiation doesn't work that way either, probably since a real port no. must be provided, but how to set these up!?

I have not much of a clue of all the SIP-stuff and really got stuck here :-/

any help appreciated, cheers,

stesie

PS: I've tried version 0.6.3 and Git/master