diff options
| -rw-r--r-- | res/res_pjsip_session.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/res/res_pjsip_session.c b/res/res_pjsip_session.c index 80fe8f393..59d759fdc 100644 --- a/res/res_pjsip_session.c +++ b/res/res_pjsip_session.c @@ -1125,7 +1125,54 @@ static pj_bool_t session_reinvite_on_rx_request(pjsip_rx_data *rdata) } if (!sdp_info->sdp) { + const pjmedia_sdp_session *local; + int i; + ast_queue_unhold(session->channel); + + pjmedia_sdp_neg_get_active_local(session->inv_session->neg, &local); + if (!local) { + return PJ_FALSE; + } + + /* + * Some devices indicate hold with deferred SDP reinvites (i.e. no SDP in the reinvite). + * When hold is initially indicated, we + * - Receive an INVITE with no SDP + * - Send a 200 OK with SDP, indicating sendrecv in the media streams + * - Receive an ACK with SDP, indicating sendonly in the media streams + * + * At this point, the pjmedia negotiator saves the state of the media direction so that + * if we are to send any offers, we'll offer recvonly in the media streams. This is + * problematic if the device is attempting to unhold, though. If the device unholds + * by sending a reinvite with no SDP, then we will respond with a 200 OK with recvonly. + * According to RFC 3264, if an offerer offers recvonly, then the answerer MUST respond + * with sendonly or inactive. The result of this is that the stream is not off hold. + * + * Therefore, in this case, when we receive a reinvite while the stream is on hold, we + * need to be sure to offer sendrecv. This way, the answerer can respond with sendrecv + * in order to get the stream off hold. If this is actually a different purpose reinvite + * (like a session timer refresh), then the answerer can respond to our sendrecv with + * sendonly, keeping the stream on hold. + */ + for (i = 0; i < local->media_count; ++i) { + pjmedia_sdp_media *m = local->media[i]; + pjmedia_sdp_attr *recvonly; + pjmedia_sdp_attr *inactive; + + recvonly = pjmedia_sdp_attr_find2(m->attr_count, m->attr, "recvonly", NULL); + inactive = pjmedia_sdp_attr_find2(m->attr_count, m->attr, "inactive", NULL); + if (recvonly || inactive) { + pjmedia_sdp_attr *to_remove = recvonly ?: inactive; + pjmedia_sdp_attr *sendrecv; + + pjmedia_sdp_attr_remove(&m->attr_count, m->attr, to_remove); + + sendrecv = pjmedia_sdp_attr_create(session->inv_session->pool, "sendrecv", NULL); + pjmedia_sdp_media_add_attr(m, sendrecv); + } + } + return PJ_FALSE; } |