Handle AVPF and SAVPF profiles.

coreapi/bellesip_sal/sal_op_call.c

@@ -70,7 +70,7 @@ static void sdp_process(SalOp *h){
 			strcpy(h->result->streams[i].rtcp_addr,h->base.remote_media->streams[i].rtcp_addr);
 			h->result->streams[i].rtcp_port=h->base.remote_media->streams[i].rtcp_port;
 
-			if (h->result->streams[i].proto == SalProtoRtpSavp) {
+			if ((h->result->streams[i].proto == SalProtoRtpSavpf) || (h->result->streams[i].proto == SalProtoRtpSavp)) {
 				h->result->streams[i].crypto[0] = h->base.remote_media->streams[i].crypto[0];
 			}
 		}

coreapi/bellesip_sal/sal_sdp.c

@@ -143,7 +143,7 @@ static void stream_description_to_sdp ( belle_sdp_session_description_t *session
 	if ( stream->bandwidth>0 )
 		belle_sdp_media_description_set_bandwidth ( media_desc,"AS",stream->bandwidth );
 
-	if ( stream->proto == SalProtoRtpSavp ) {
+	if ((stream->proto == SalProtoRtpSavpf) || (stream->proto == SalProtoRtpSavp)) {
 		/* add crypto lines */
 		for ( j=0; j<SAL_CRYPTO_ALGO_MAX; j++ ) {
 			MSCryptoSuiteNameParams desc;
@@ -469,11 +469,15 @@ static SalStreamDescription * sdp_to_stream_description(SalMediaDescription *md,
 	proto = belle_sdp_media_get_protocol ( media );
 	stream->proto=SalProtoOther;
 	if ( proto ) {
-		if ( strcasecmp ( proto,"RTP/AVP" ) ==0 )
-			stream->proto=SalProtoRtpAvp;
-		else if ( strcasecmp ( proto,"RTP/SAVP" ) ==0 ) {
-			stream->proto=SalProtoRtpSavp;
-		}else{
+		if (strcasecmp(proto, "RTP/AVP") == 0) {
+			stream->proto = SalProtoRtpAvp;
+		} else if (strcasecmp(proto, "RTP/SAVP") == 0) {
+			stream->proto = SalProtoRtpSavp;
+		} else if (strcasecmp(proto, "RTP/AVPF") == 0) {
+			stream->proto = SalProtoRtpAvpf;
+		} else if (strcasecmp(proto, "RTP/SAVPF") == 0) {
+			stream->proto = SalProtoRtpSavpf;
+		} else {
 			strncpy(stream->proto_other,proto,sizeof(stream->proto_other)-1);
 		}
 	}
@@ -532,7 +536,7 @@ static SalStreamDescription * sdp_to_stream_description(SalMediaDescription *md,
 	}
 
 	/* Read crypto lines if any */
-	if ( stream->proto == SalProtoRtpSavp ) {
+	if ((stream->proto == SalProtoRtpSavpf) || (stream->proto == SalProtoRtpSavp)) {
 		sdp_parse_media_crypto_parameters(media_desc, stream);
 	}
 

coreapi/callbacks.c

@@ -670,24 +670,32 @@ static void call_failure(SalOp *op){
 		break;
 		case SalReasonUnsupportedContent: /*<this is for compatibility: linphone sent 415 because of SDP offer answer failure*/
 		case SalReasonNotAcceptable:
-		//media_encryption_mandatory
-			if (call->params.media_encryption == LinphoneMediaEncryptionSRTP && 
-				!linphone_core_is_media_encryption_mandatory(lc)) {
+			ms_message("Outgoing call [%p] failed with SRTP and/or AVPF enabled", call);
+			if ((call->state == LinphoneCallOutgoingInit)
+				|| (call->state == LinphoneCallOutgoingProgress)
+				|| (call->state == LinphoneCallOutgoingRinging) /* Push notification case */
+				|| (call->state == LinphoneCallOutgoingEarlyMedia)) {
 				int i;
-				ms_message("Outgoing call [%p] failed with SRTP (SAVP) enabled",call);
-				if (call->state==LinphoneCallOutgoingInit
-						|| call->state==LinphoneCallOutgoingProgress
-						|| call->state==LinphoneCallOutgoingRinging /*push case*/
-						|| call->state==LinphoneCallOutgoingEarlyMedia){
-					ms_message("Retrying call [%p] with AVP",call);
-					/* clear SRTP local params */
-					call->params.media_encryption = LinphoneMediaEncryptionNone;
-					for(i=0; i<call->localdesc->n_active_streams; i++) {
-						call->localdesc->streams[i].proto = SalProtoRtpAvp;
-						memset(call->localdesc->streams[i].crypto, 0, sizeof(call->localdesc->streams[i].crypto));
+				for (i = 0; i < call->localdesc->n_active_streams; i++) {
+					if (call->params.media_encryption == LinphoneMediaEncryptionSRTP) {
+						if (call->params.avpf_enabled == TRUE) {
+							if (i == 0) ms_message("Retrying call [%p] with SAVP", call);
+							call->params.avpf_enabled = FALSE;
+							linphone_core_restart_invite(lc, call);
+							return;
+						} else if (!linphone_core_is_media_encryption_mandatory(lc)) {
+							if (i == 0) ms_message("Retrying call [%p] with AVP", call);
+							call->params.media_encryption = LinphoneMediaEncryptionNone;
+							memset(call->localdesc->streams[i].crypto, 0, sizeof(call->localdesc->streams[i].crypto));
+							linphone_core_restart_invite(lc, call);
+							return;
+						}
+					} else if (call->params.avpf_enabled == TRUE) {
+						if (i == 0) ms_message("Retrying call [%p] with AVP", call);
+						call->params.avpf_enabled = FALSE;
+						linphone_core_restart_invite(lc, call);
+						return;
 					}
-					linphone_core_restart_invite(lc, call);
-					return;
 				}
 			}
 			msg=_("Incompatible media parameters.");

coreapi/linphonecall.c

@@ -265,8 +265,8 @@ static void setup_encryption_keys(LinphoneCall *call, SalMediaDescription *md){
 	bool_t keep_srtp_keys=lp_config_get_int(lc->config,"sip","keep_srtp_keys",1);
 
 	for(i=0; i<md->n_active_streams; i++) {
-		if (md->streams[i].proto == SalProtoRtpSavp) {
-			if (keep_srtp_keys && old_md && old_md->streams[i].proto==SalProtoRtpSavp){
+		if (is_encryption_active(&md->streams[i]) == TRUE) {
+			if (keep_srtp_keys && old_md && is_encryption_active(&old_md->streams[i]) == TRUE){
 				int j;
 				ms_message("Keeping same crypto keys.");
 				for(j=0;j<SAL_CRYPTO_ALGO_MAX;++j){
@@ -311,6 +311,13 @@ void linphone_call_increment_local_media_description(LinphoneCall *call){
 	md->session_ver++;
 }
 
+static SalMediaProto get_proto_from_call_params(LinphoneCallParams *params) {
+	if ((params->media_encryption == LinphoneMediaEncryptionSRTP) && params->avpf_enabled) return SalProtoRtpSavpf;
+	if (params->media_encryption == LinphoneMediaEncryptionSRTP) return SalProtoRtpSavp;
+	if (params->avpf_enabled) return SalProtoRtpAvpf;
+	return SalProtoRtpAvp;
+}
+
 void linphone_call_make_local_media_description(LinphoneCore *lc, LinphoneCall *call){
 	MSList *l;
 	PayloadType *pt;
@@ -349,8 +356,7 @@ void linphone_call_make_local_media_description(LinphoneCore *lc, LinphoneCall *
 	strncpy(md->streams[0].name,"Audio",sizeof(md->streams[0].name)-1);
 	md->streams[0].rtp_port=call->media_ports[0].rtp_port;
 	md->streams[0].rtcp_port=call->media_ports[0].rtcp_port;
-	md->streams[0].proto=(call->params.media_encryption == LinphoneMediaEncryptionSRTP) ?
-		SalProtoRtpSavp : SalProtoRtpAvp;
+	md->streams[0].proto=get_proto_from_call_params(&call->params);
 	md->streams[0].type=SalAudio;
 	if (call->params.down_ptime)
 		md->streams[0].ptime=call->params.down_ptime;
@@ -961,10 +967,6 @@ const LinphoneCallParams * linphone_call_get_current_params(LinphoneCall *call){
 	return &call->current_params;
 }
 
-static bool_t is_video_active(const SalStreamDescription *sd){
-	return sd->rtp_port!=0 && sd->dir!=SalStreamInactive;
-}
-
 /**
  * Returns call parameters proposed by remote.
  *
@@ -976,19 +978,20 @@ const LinphoneCallParams * linphone_call_get_remote_params(LinphoneCall *call){
 	memset(cp,0,sizeof(*cp));
 	if (call->op){
 		SalMediaDescription *md=sal_call_get_remote_media_description(call->op);
-		if (md){
-			SalStreamDescription *asd,*vsd,*secure_asd,*secure_vsd;
-
-			asd=sal_media_description_find_stream(md,SalProtoRtpAvp,SalAudio);
-			vsd=sal_media_description_find_stream(md,SalProtoRtpAvp,SalVideo);
-			secure_asd=sal_media_description_find_stream(md,SalProtoRtpSavp,SalAudio);
-			secure_vsd=sal_media_description_find_stream(md,SalProtoRtpSavp,SalVideo);
-			if (secure_vsd){
-				cp->has_video=is_video_active(secure_vsd);
-				if (secure_asd || asd==NULL)
-					cp->media_encryption=LinphoneMediaEncryptionSRTP;
-			}else if (vsd){
-				cp->has_video=is_video_active(vsd);
+		if (md) {
+			SalStreamDescription *sd;
+			unsigned int i;
+			unsigned int nb_audio_streams = sal_media_description_nb_active_streams_of_type(md, SalAudio);
+			unsigned int nb_video_streams = sal_media_description_nb_active_streams_of_type(md, SalVideo);
+
+			for (i = 0; i < nb_video_streams; i++) {
+				sd = sal_media_description_get_active_stream_of_type(md, SalVideo, i);
+				if (is_video_active(sd) == TRUE) cp->has_video = TRUE;
+				if (is_encryption_active(sd) == TRUE) cp->media_encryption = LinphoneMediaEncryptionSRTP;
+			}
+			for (i = 0; i < nb_audio_streams; i++) {
+				sd = sal_media_description_get_active_stream_of_type(md, SalAudio, i);
+				if (is_encryption_active(sd) == TRUE) cp->media_encryption = LinphoneMediaEncryptionSRTP;
 			}
 			if (!cp->has_video){
 				if (md->bandwidth>0 && md->bandwidth<=linphone_core_get_edge_bw(call->core)){
@@ -1861,12 +1864,10 @@ static void configure_rtp_session_for_rtcp_xr(LinphoneCore *lc, LinphoneCall *ca
 	const SalStreamDescription *localstream;
 	const SalStreamDescription *remotestream;
 
-	localstream = sal_media_description_find_stream(call->localdesc, SalProtoRtpSavp, type);
-	if (!localstream) localstream = sal_media_description_find_stream(call->localdesc, SalProtoRtpAvp, type);
+	localstream = sal_media_description_find_best_stream(call->localdesc, type);
 	if (!localstream) return;
 	localconfig = &localstream->rtcp_xr;
-	remotestream = sal_media_description_find_stream(sal_call_get_remote_media_description(call->op), SalProtoRtpSavp, type);
-	if (!remotestream) remotestream = sal_media_description_find_stream(sal_call_get_remote_media_description(call->op), SalProtoRtpAvp, type);
+	remotestream = sal_media_description_find_best_stream(sal_call_get_remote_media_description(call->op), type);
 	if (!remotestream) return;
 	remoteconfig = &remotestream->rtcp_xr;
 
@@ -1902,14 +1903,8 @@ static void linphone_call_start_audio_stream(LinphoneCall *call, const char *cna
 	int crypto_idx;
 
 	snprintf(rtcp_tool,sizeof(rtcp_tool)-1,"%s-%s",linphone_core_get_user_agent_name(),linphone_core_get_user_agent_version());
-	/* look for savp stream first */
-	stream=sal_media_description_find_stream(call->resultdesc,
-							SalProtoRtpSavp,SalAudio);
-	/* no savp audio stream, use avp */
-	if (!stream)
-		stream=sal_media_description_find_stream(call->resultdesc,
-							SalProtoRtpAvp,SalAudio);
 
+	stream = sal_media_description_find_best_stream(call->resultdesc, SalAudio);
 	if (stream && stream->dir!=SalStreamInactive && stream->rtp_port!=0){
 		playcard=lc->sound_conf.lsd_card ?
 			lc->sound_conf.lsd_card : lc->sound_conf.play_sndcard;
@@ -1965,8 +1960,8 @@ static void linphone_call_start_audio_stream(LinphoneCall *call, const char *cna
 				call->current_params.record_file=ms_strdup(call->params.record_file);
 			}
 			/* valid local tags are > 0 */
-			if (stream->proto == SalProtoRtpSavp) {
-				local_st_desc=sal_media_description_find_stream(call->localdesc,SalProtoRtpSavp,SalAudio);
+			if (is_encryption_active(stream) == TRUE) {
+				local_st_desc=sal_media_description_find_stream(call->localdesc,stream->proto,SalAudio);
 				crypto_idx = find_crypto_index_from_tag(local_st_desc->crypto, stream->crypto_local_tag);
 
 				if (crypto_idx >= 0) {
@@ -2020,17 +2015,10 @@ static void linphone_call_start_video_stream(LinphoneCall *call, const char *cna
 #ifdef VIDEO_ENABLED
 	LinphoneCore *lc=call->core;
 	int used_pt=-1;
-
-	/* look for savp stream first */
-	const SalStreamDescription *vstream=sal_media_description_find_stream(call->resultdesc,
-							SalProtoRtpSavp,SalVideo);
 	char rtcp_tool[128]={0};
-	snprintf(rtcp_tool,sizeof(rtcp_tool)-1,"%s-%s",linphone_core_get_user_agent_name(),linphone_core_get_user_agent_version());
+	const SalStreamDescription *vstream;
 
-	/* no savp audio stream, use avp */
-	if (!vstream)
-		vstream=sal_media_description_find_stream(call->resultdesc,
-							SalProtoRtpAvp,SalVideo);
+	snprintf(rtcp_tool,sizeof(rtcp_tool)-1,"%s-%s",linphone_core_get_user_agent_name(),linphone_core_get_user_agent_version());
 
 	/* shutdown preview */
 	if (lc->previewstream!=NULL) {
@@ -2038,6 +2026,7 @@ static void linphone_call_start_video_stream(LinphoneCall *call, const char *cna
 		lc->previewstream=NULL;
 	}
 
+	vstream = sal_media_description_find_best_stream(call->resultdesc, SalVideo);
 	if (vstream!=NULL && vstream->dir!=SalStreamInactive && vstream->rtp_port!=0) {
 		const char *rtp_addr=vstream->rtp_addr[0]!='\0' ? vstream->rtp_addr : call->resultdesc->addr;
 		const char *rtcp_addr=vstream->rtcp_addr[0]!='\0' ? vstream->rtcp_addr : call->resultdesc->addr;
@@ -2088,7 +2077,7 @@ static void linphone_call_start_video_stream(LinphoneCall *call, const char *cna
 				cam=get_nowebcam_device();
 			}
 			if (!is_inactive){
-				if (vstream->proto == SalProtoRtpSavp) {
+				if (is_encryption_active(vstream) == TRUE) {
 					int crypto_idx = find_crypto_index_from_tag(local_st_desc->crypto, vstream->crypto_local_tag);
 					if (crypto_idx >= 0) {
 						media_stream_set_srtp_recv_key(&call->videostream->ms,vstream->crypto[0].algo,vstream->crypto[0].master_key);
@@ -2121,8 +2110,7 @@ void linphone_call_start_media_streams(LinphoneCall *call, bool_t all_inputs_mut
 	char *cname;
 	bool_t use_arc=linphone_core_adaptive_rate_control_enabled(lc);
 #ifdef VIDEO_ENABLED
-	const SalStreamDescription *vstream=sal_media_description_find_stream(call->resultdesc,
-								SalProtoRtpAvp,SalVideo);
+	const SalStreamDescription *vstream=sal_media_description_find_best_stream(call->resultdesc,SalVideo);
 #endif
 
 	call->current_params.audio_codec = NULL;
@@ -2209,17 +2197,17 @@ void linphone_call_update_crypto_parameters(LinphoneCall *call, SalMediaDescript
 	SalStreamDescription *new_stream;
 	const SalStreamDescription *local_st_desc;
 
-	local_st_desc = sal_media_description_find_stream(call->localdesc, SalProtoRtpSavp, SalAudio);
-	old_stream = sal_media_description_find_stream(old_md, SalProtoRtpSavp, SalAudio);
-	new_stream = sal_media_description_find_stream(new_md, SalProtoRtpSavp, SalAudio);
+	local_st_desc = sal_media_description_find_secure_stream_of_type(call->localdesc, SalAudio);
+	old_stream = sal_media_description_find_secure_stream_of_type(old_md, SalAudio);
+	new_stream = sal_media_description_find_secure_stream_of_type(new_md, SalAudio);
 	if (call->audiostream && local_st_desc && old_stream && new_stream &&
 		update_stream_crypto_params(call,local_st_desc,old_stream,new_stream,&call->audiostream->ms)){
 	}
 
 #ifdef VIDEO_ENABLED
-	local_st_desc = sal_media_description_find_stream(call->localdesc, SalProtoRtpSavp, SalVideo);
-	old_stream = sal_media_description_find_stream(old_md, SalProtoRtpSavp, SalVideo);
-	new_stream = sal_media_description_find_stream(new_md, SalProtoRtpSavp, SalVideo);
+	local_st_desc = sal_media_description_find_secure_stream_of_type(call->localdesc, SalVideo);
+	old_stream = sal_media_description_find_secure_stream_of_type(old_md, SalVideo);
+	new_stream = sal_media_description_find_secure_stream_of_type(new_md, SalVideo);
 	if (call->videostream && local_st_desc && old_stream && new_stream &&
 		update_stream_crypto_params(call,local_st_desc,old_stream,new_stream,&call->videostream->ms)){
 	}

coreapi/linphonecore.c

@@ -2972,7 +2972,7 @@ bool_t linphone_core_media_description_has_srtp(const SalMediaDescription *md){
 
 	for(i=0;i<md->n_active_streams;i++){
 		const SalStreamDescription *sd=&md->streams[i];
-		if (sd->proto!=SalProtoRtpSavp){
+		if (is_encryption_active(sd) != TRUE){
 			return FALSE;
 		}
 	}

coreapi/misc.c

@@ -1520,3 +1520,10 @@ const MSCryptoSuite * linphone_core_get_srtp_crypto_suites(LinphoneCore *lc){
 	return result;
 }
 
+bool_t is_video_active(const SalStreamDescription *sd) {
+	return (sd->rtp_port != 0) && (sd->dir != SalStreamInactive);
+}
+
+bool_t is_encryption_active(const SalStreamDescription *sd) {
+	return ((sd->proto == SalProtoRtpSavpf) || (sd->proto == SalProtoRtpSavp));
+}

coreapi/offeranswer.c

@@ -233,7 +233,7 @@ static void initiate_outgoing(const SalStreamDescription *local_offer,
 	}else{
 		result->rtp_port=0;
 	}
-	if (result->proto == SalProtoRtpSavp) {
+	if (is_encryption_active(result) == TRUE) {
 		/* verify crypto algo */
 		memset(result->crypto, 0, sizeof(result->crypto));
 		if (!match_crypto_algo(local_offer->crypto, remote_answer->crypto, &result->crypto[0], &result->crypto_local_tag, FALSE))
@@ -259,7 +259,7 @@ static void initiate_incoming(const SalStreamDescription *local_cap,
 	}else{
 		result->rtp_port=0;
 	}
-	if (result->proto == SalProtoRtpSavp) {
+	if (is_encryption_active(result) == TRUE) {
 		/* select crypto algo */
 		memset(result->crypto, 0, sizeof(result->crypto));
 		if (!match_crypto_algo(local_cap->crypto, remote_offer->crypto, &result->crypto[0], &result->crypto_local_tag, TRUE))
@@ -323,10 +323,11 @@ static bool_t local_stream_not_already_used(const SalMediaDescription *result, c
 	return TRUE;
 }
 
-/*in answering mode, we consider that if we are able to make SAVP, then we can do AVP as well*/
+/*in answering mode, we consider that if we are able to make AVPF/SAVP/SAVPF, then we can do AVP as well*/
 static bool_t proto_compatible(SalMediaProto local, SalMediaProto remote){
 	if (local==remote) return TRUE;
-	if (remote==SalProtoRtpAvp && local==SalProtoRtpSavp) return TRUE;
+	if ((remote==SalProtoRtpAvp) && ((local==SalProtoRtpSavp) || (local==SalProtoRtpAvpf) || (local==SalProtoRtpSavpf)))
+		return TRUE;
 	return FALSE;
 }
 

coreapi/private.h

@@ -95,6 +95,7 @@ struct _LinphoneCallParams{
 	char *session_name;
 	SalCustomHeader *custom_headers;
 	bool_t has_video;
+	bool_t avpf_enabled; /* RTCP feedback messages are enabled */
 	bool_t real_early_media; /*send real media even during early media (for outgoing calls)*/
 	bool_t in_conference; /*in conference mode */
 	bool_t low_bandwidth;
@@ -389,6 +390,8 @@ bool_t linphone_core_rtcp_enabled(const LinphoneCore *lc);
 
 LinphoneCall * is_a_linphone_call(void *user_pointer);
 LinphoneProxyConfig * is_a_linphone_proxy_config(void *user_pointer);
+bool_t is_video_active(const SalStreamDescription *sd);
+bool_t is_encryption_active(const SalStreamDescription *sd);
 
 void linphone_core_queue_task(LinphoneCore *lc, belle_sip_source_func_t task_fun, void *data, const char *task_description);
 

coreapi/sal.c

@@ -91,6 +91,39 @@ SalStreamDescription *sal_media_description_find_stream(SalMediaDescription *md,
 	return NULL;
 }
 
+unsigned int sal_media_description_nb_active_streams_of_type(SalMediaDescription *md, SalStreamType type) {
+	unsigned int i;
+	unsigned int nb = 0;
+	for (i = 0; i < md->n_active_streams; ++i) {
+		if (md->streams[i].type == type) nb++;
+	}
+	return nb;
+}
+
+SalStreamDescription * sal_media_description_get_active_stream_of_type(SalMediaDescription *md, SalStreamType type, unsigned int idx) {
+	unsigned int i;
+	for (i = 0; i < md->n_active_streams; ++i) {
+		if (md->streams[i].type == type) {
+			if (idx-- == 0) return &md->streams[i];
+		}
+	}
+	return NULL;
+}
+
+SalStreamDescription * sal_media_description_find_secure_stream_of_type(SalMediaDescription *md, SalStreamType type) {
+	SalStreamDescription *desc = sal_media_description_find_stream(md, SalProtoRtpSavpf, type);
+	if (desc == NULL) desc = sal_media_description_find_stream(md, SalProtoRtpSavp, type);
+	return desc;
+}
+
+SalStreamDescription * sal_media_description_find_best_stream(SalMediaDescription *md, SalStreamType type) {
+	SalStreamDescription *desc = sal_media_description_find_stream(md, SalProtoRtpSavpf, type);
+	if (desc == NULL) desc = sal_media_description_find_stream(md, SalProtoRtpSavp, type);
+	if (desc == NULL) desc = sal_media_description_find_stream(md, SalProtoRtpAvpf, type);
+	if (desc == NULL) desc = sal_media_description_find_stream(md, SalProtoRtpAvp, type);
+	return desc;
+}
+
 bool_t sal_media_description_empty(const SalMediaDescription *md){
 	if (md->n_active_streams > 0) return FALSE;
 	return TRUE;
@@ -515,6 +548,8 @@ const char* sal_media_proto_to_string(SalMediaProto type) {
 	switch (type) {
 	case SalProtoRtpAvp:return "RTP/AVP";
 	case SalProtoRtpSavp:return "RTP/SAVP";
+	case SalProtoRtpAvpf:return "RTP/AVPF";
+	case SalProtoRtpSavpf:return "RTP/SAVPF";
 	default: return "unknown";
 	}
 }

include/sal/sal.h

@@ -123,6 +123,8 @@ const char* sal_stream_type_to_string(SalStreamType type);
 typedef enum{
 	SalProtoRtpAvp,
 	SalProtoRtpSavp,
+	SalProtoRtpAvpf,
+	SalProtoRtpSavpf,
 	SalProtoOther
 }SalMediaProto;
 const char* sal_media_proto_to_string(SalMediaProto type);
@@ -251,6 +253,10 @@ int sal_media_description_equals(const SalMediaDescription *md1, const SalMediaD
 bool_t sal_media_description_has_dir(const SalMediaDescription *md, SalStreamDir dir);
 SalStreamDescription *sal_media_description_find_stream(SalMediaDescription *md,
     SalMediaProto proto, SalStreamType type);
+unsigned int sal_media_description_nb_active_streams_of_type(SalMediaDescription *md, SalStreamType type);
+SalStreamDescription * sal_media_description_get_active_stream_of_type(SalMediaDescription *md, SalStreamType type, unsigned int idx);
+SalStreamDescription * sal_media_description_find_secure_stream_of_type(SalMediaDescription *md, SalStreamType type);
+SalStreamDescription * sal_media_description_find_best_stream(SalMediaDescription *md, SalStreamType type);
 void sal_media_description_set_dir(SalMediaDescription *md, SalStreamDir stream_dir);