void rtp_session_rtp_parse(RtpSession *session, mblk_t *mp, uint32_t local_str_ts, struct sockaddr *addr, socklen_t addrlen)
{
int i;
int discarded;
int duplicate;
rtp_header_t *rtp;
int msgsize;
RtpStream *rtpstream=&session->rtp;
rtp_stats_t *stats=&rtpstream->stats;
msgsize=(int)(mp->b_wptr-mp->b_rptr);
if (msgsize<RTP_FIXED_HEADER_SIZE){
ortp_warning("Packet too small to be a rtp packet (%i)!",msgsize);
rtpstream->stats.bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
rtp=(rtp_header_t*)mp->b_rptr;
if (rtp->version!=2)
{
/* try to see if it is a STUN packet */
uint16_t stunlen=*((uint16_t*)(mp->b_rptr + sizeof(uint16_t)));
stunlen = ntohs(stunlen);
if (stunlen+20==mp->b_wptr-mp->b_rptr){
/* this looks like a stun packet */
if (session->eventqs!=NULL){
OrtpEvent *ev=ortp_event_new(ORTP_EVENT_STUN_PACKET_RECEIVED);
OrtpEventData *ed=ortp_event_get_data(ev);
ed->packet=mp;
memcpy(&ed->source_addr,addr,addrlen);
ed->source_addrlen=addrlen;
ed->info.socket_type = OrtpRTPSocket;
rtp_session_dispatch_event(session,ev);
return;
}
}
/* discard in two case: the packet is not stun OR nobody is interested by STUN (no eventqs) */
ortp_debug("Receiving rtp packet with version number !=2...discarded");
stats->bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
/* only count non-stun packets. */
ortp_global_stats.packet_recv++;
stats->packet_recv++;
ortp_global_stats.hw_recv+=msgsize;
stats->hw_recv+=msgsize;
session->rtp.hwrcv_since_last_SR++;
session->rtcp_xr_stats.rcv_since_last_stat_summary++;
/* convert all header data from network order to host order */
rtp->seq_number=ntohs(rtp->seq_number);
rtp->timestamp=ntohl(rtp->timestamp);
rtp->ssrc=ntohl(rtp->ssrc);
/* convert csrc if necessary */
if (rtp->cc*sizeof(uint32_t) > (uint32_t) (msgsize-RTP_FIXED_HEADER_SIZE)){
ortp_debug("Receiving too short rtp packet.");
stats->bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
#ifndef PERF
/* Write down the last RTP/RTCP packet reception time. */
ortp_gettimeofday(&session->last_recv_time, NULL);
#endif
for (i=0;i<rtp->cc;i++)
rtp->csrc[i]=ntohl(rtp->csrc[i]);
/*the goal of the following code is to lock on an incoming SSRC to avoid
receiving "mixed streams"*/
if (session->ssrc_set){
/*the ssrc is set, so we must check it */
if (session->rcv.ssrc!=rtp->ssrc){
if (session->inc_ssrc_candidate==rtp->ssrc){
session->inc_same_ssrc_count++;
}else{
session->inc_same_ssrc_count=0;
session->inc_ssrc_candidate=rtp->ssrc;
}
if (session->inc_same_ssrc_count>=session->rtp.ssrc_changed_thres){
/* store the sender rtp address to do symmetric RTP */
if (!session->use_connect){
if (session->rtp.gs.socket>0 && session->symmetric_rtp){
/* store the sender rtp address to do symmetric RTP */
memcpy(&session->rtp.gs.rem_addr,addr,addrlen);
session->rtp.gs.rem_addrlen=addrlen;
}
}
session->rtp.rcv_last_ts = rtp->timestamp;
session->rcv.ssrc=rtp->ssrc;
rtp_signal_table_emit(&session->on_ssrc_changed);
}else{
/*discard the packet*/
ortp_debug("Receiving packet with unknown ssrc.");
stats->bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
} else{
/* The SSRC change must not happen if we still receive
ssrc from the initial source. */
session->inc_same_ssrc_count=0;
}
}else{
session->ssrc_set=TRUE;
session->rcv.ssrc=rtp->ssrc;
if (!session->use_connect){
if (session->rtp.gs.socket>0 && session->symmetric_rtp){
/* store the sender rtp address to do symmetric RTP */
memcpy(&session->rtp.gs.rem_addr,addr,addrlen);
session->rtp.gs.rem_addrlen=addrlen;
}
}
}
/* update some statistics */
{
poly32_t *extseq=(poly32_t*)&rtpstream->hwrcv_extseq;
if (rtp->seq_number>extseq->split.lo){
extseq->split.lo=rtp->seq_number;
}else if (rtp->seq_number<200 && extseq->split.lo>((1<<16) - 200)){
/* this is a check for sequence number looping */
extseq->split.lo=rtp->seq_number;
extseq->split.hi++;
}
/* the first sequence number received should be initialized at the beginning
or at any resync, so that the first receiver reports contains valid loss rate*/
if (!(session->flags & RTP_SESSION_RECV_SEQ_INIT)){
rtp_session_set_flag(session, RTP_SESSION_RECV_SEQ_INIT);
rtpstream->hwrcv_seq_at_last_SR=rtp->seq_number-1;
session->rtcp_xr_stats.rcv_seq_at_last_stat_summary=rtp->seq_number-1;
}
if (stats->packet_recv==1){
session->rtcp_xr_stats.first_rcv_seq=extseq->one;
}
session->rtcp_xr_stats.last_rcv_seq=extseq->one;
}
/* check for possible telephone events */
if (rtp_profile_is_telephone_event(session->snd.profile, rtp->paytype)){
queue_packet(&session->rtp.tev_rq,session->rtp.max_rq_size,mp,rtp,&discarded,&duplicate);
stats->discarded+=discarded;
ortp_global_stats.discarded+=discarded;
stats->packet_dup_recv+=duplicate;
ortp_global_stats.packet_dup_recv+=duplicate;
session->rtcp_xr_stats.discarded_count += discarded;
session->rtcp_xr_stats.dup_since_last_stat_summary += duplicate;
return;
}
/* check for possible payload type change, in order to update accordingly our clock-rate dependant
parameters */
if (session->hw_recv_pt!=rtp->paytype){
rtp_session_update_payload_type(session,rtp->paytype);
}
/* Drop the packets while the RTP_SESSION_FLUSH flag is set. */
if (session->flags & RTP_SESSION_FLUSH) {
freemsg(mp);
return;
}
jitter_control_new_packet(&session->rtp.jittctl,rtp->timestamp,local_str_ts);
update_rtcp_xr_stat_summary(session, mp, local_str_ts);
if (session->flags & RTP_SESSION_FIRST_PACKET_DELIVERED) {
/* detect timestamp important jumps in the future, to workaround stupid rtp senders */
if (RTP_TIMESTAMP_IS_NEWER_THAN(rtp->timestamp,session->rtp.rcv_last_ts+session->rtp.ts_jump)){
ortp_warning("rtp_parse: timestamp jump in the future detected.");
rtp_signal_table_emit2(&session->on_timestamp_jump,&rtp->timestamp);
}
else if (RTP_TIMESTAMP_IS_STRICTLY_NEWER_THAN(session->rtp.rcv_last_ts,rtp->timestamp)
|| RTP_SEQ_IS_STRICTLY_GREATER_THAN(session->rtp.rcv_last_seq,rtp->seq_number)){
/* don't queue packets older than the last returned packet to the application, or whose sequence number
is behind the last packet returned to the application*/
/* Call timstamp jumb in case of
* large negative Ts jump or if ts is set to 0
*/
if ( RTP_TIMESTAMP_IS_STRICTLY_NEWER_THAN(session->rtp.rcv_last_ts, rtp->timestamp + session->rtp.ts_jump) ){
ortp_warning("rtp_parse: negative timestamp jump detected");
rtp_signal_table_emit2(&session->on_timestamp_jump, &rtp->timestamp);
}
ortp_debug("rtp_parse: discarding too old packet (ts=%i)",rtp->timestamp);
freemsg(mp);
stats->outoftime++;
ortp_global_stats.outoftime++;
session->rtcp_xr_stats.discarded_count++;
return;
}
}
if (queue_packet(&session->rtp.rq,session->rtp.max_rq_size,mp,rtp,&discarded,&duplicate))
jitter_control_update_size(&session->rtp.jittctl,&session->rtp.rq);
stats->discarded+=discarded;
ortp_global_stats.discarded+=discarded;
stats->packet_dup_recv+=duplicate;
ortp_global_stats.packet_dup_recv+=duplicate;
session->rtcp_xr_stats.discarded_count += discarded;
session->rtcp_xr_stats.dup_since_last_stat_summary += duplicate;
if ((discarded == 0) && (duplicate == 0)) {
session->rtcp_xr_stats.rcv_count++;
}
}
void rtp_session_rtp_parse(RtpSession *session, mblk_t *mp, uint32_t local_str_ts, struct sockaddr *addr, socklen_t addrlen)
{
int i;
rtp_header_t *rtp;
int msgsize;
RtpStream *rtpstream=&session->rtp;
rtp_stats_t *stats=&rtpstream->stats;
return_if_fail(mp!=NULL);
msgsize=msgdsize(mp);
if (msgsize<RTP_FIXED_HEADER_SIZE){
ortp_warning("Packet too small to be a rtp packet (%i)!",msgsize);
rtpstream->stats.bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
rtp=(rtp_header_t*)mp->b_rptr;
if (rtp->version!=2)
{
/* try to see if it is a STUN packet */
uint16_t stunlen=*((uint16_t*)(mp->b_rptr + sizeof(uint16_t)));
stunlen = ntohs(stunlen);
if (stunlen+20==mp->b_wptr-mp->b_rptr){
/* this looks like a stun packet */
if (session->eventqs!=NULL){
OrtpEvent *ev=ortp_event_new(ORTP_EVENT_STUN_PACKET_RECEIVED);
OrtpEventData *ed=ortp_event_get_data(ev);
ed->packet=mp;
ed->ep=rtp_endpoint_new(addr,addrlen);
rtp_session_dispatch_event(session,ev);
return;
}
}
freemsg(mp);
return;
}
/* only count non-stun packets. */
ortp_global_stats.packet_recv++;
stats->packet_recv++;
ortp_global_stats.hw_recv+=msgsize;
stats->hw_recv+=msgsize;
session->rtp.hwrcv_since_last_SR++;
if (rtp->version!=2)
{
/* discard*/
ortp_debug("Receiving rtp packet with version number !=2...discarded");
stats->bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
/* convert all header data from network order to host order */
rtp->seq_number=ntohs(rtp->seq_number);
rtp->timestamp=ntohl(rtp->timestamp);
rtp->ssrc=ntohl(rtp->ssrc);
/* convert csrc if necessary */
if (rtp->cc*sizeof(uint32_t) > (uint32_t) (msgsize-RTP_FIXED_HEADER_SIZE)){
ortp_debug("Receiving too short rtp packet.");
stats->bad++;
ortp_global_stats.bad++;
freemsg(mp);
return;
}
/* Write down the last RTP/RTCP packet reception time. */
gettimeofday(&session->last_recv_time, NULL);
for (i=0;i<rtp->cc;i++)
rtp->csrc[i]=ntohl(rtp->csrc[i]);
if (session->rcv.ssrc!=0)
{
/*the ssrc is set, so we must check it */
if (session->rcv.ssrc!=rtp->ssrc){
/*ortp_debug("rtp_parse: bad ssrc - %i",rtp->ssrc);*/
session->rcv.ssrc=rtp->ssrc;
rtp_signal_table_emit(&session->on_ssrc_changed);
}
}else session->rcv.ssrc=rtp->ssrc;
/* update some statistics */
{
poly32_t *extseq=(poly32_t*)&rtpstream->hwrcv_extseq;
if (rtp->seq_number>extseq->split.lo){
extseq->split.lo=rtp->seq_number;
}else if (rtp->seq_number<200 && extseq->split.lo>((1<<16) - 200)){
/* this is a check for sequence number looping */
extseq->split.lo=rtp->seq_number;
extseq->split.hi++;
}
}
/* check for possible telephone events */
if (rtp->paytype==session->rcv.telephone_events_pt){
split_and_queue(&session->rtp.tev_rq,session->rtp.max_rq_size,mp,rtp,&i);
stats->discarded+=i;
ortp_global_stats.discarded+=i;
return;
}
/* check for possible payload type change, in order to update accordingly our clock-rate dependant
parameters */
if (session->hw_recv_pt!=rtp->paytype){
rtp_session_update_payload_type(session,rtp->paytype);
}
if (session->flags & RTP_SESSION_FIRST_PACKET_DELIVERED) {
int32_t slide=0;
int32_t safe_delay=0;
jitter_control_new_packet(&session->rtp.jittctl,rtp->timestamp,local_str_ts,&slide,&safe_delay);
session->rtp.rcv_diff_ts=session->rtp.hwrcv_diff_ts + slide - safe_delay;
ortp_debug(" rcv_diff_ts=%i", session->rtp.rcv_diff_ts);
/* detect timestamp important jumps in the future, to workaround stupid rtp senders */
if (RTP_TIMESTAMP_IS_NEWER_THAN(rtp->timestamp,session->rtp.rcv_last_ts+session->rtp.ts_jump)){
ortp_debug("rtp_parse: timestamp jump ?");
rtp_signal_table_emit2(&session->on_timestamp_jump,(long)&rtp->timestamp);
}
else if (RTP_TIMESTAMP_IS_STRICTLY_NEWER_THAN(session->rtp.rcv_last_ts,rtp->timestamp)){
/* don't queue packets older than the last returned packet to the application*/
/* Call timstamp jumb in case of
* large negative Ts jump or if ts is set to 0
*/
if ( RTP_TIMESTAMP_IS_STRICTLY_NEWER_THAN(session->rtp.rcv_last_ts, rtp->timestamp + session->rtp.ts_jump) ){
ortp_warning("rtp_parse: negative timestamp jump");
rtp_signal_table_emit2(&session->on_timestamp_jump,
(long)&rtp->timestamp);
}
ortp_debug("rtp_parse: discarding too old packet (ts=%i)",rtp->timestamp);
freemsg(mp);
stats->outoftime++;
ortp_global_stats.outoftime++;
return;
}
}
split_and_queue(&session->rtp.rq,session->rtp.max_rq_size,mp,rtp,&i);
stats->discarded+=i;
ortp_global_stats.discarded+=i;
}
