MT#55283 add `allow-asymmetric-codecs` option

Change-Id: I6e9a6e04b9e6192b906c872e478784efb3fe5c6a

daemon/call.c

@@ -2385,7 +2385,8 @@ static void codecs_offer(struct call_media *media, struct call_media *other_medi
 					.codec_set = flags->codec_set);
 		else
 			codec_store_populate(&other_media->codecs, &sp->codecs,
-					.codec_set = flags->codec_set);
+					.codec_set = flags->codec_set,
+					.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 		codec_store_strip(&other_media->codecs, &flags->codec_strip, flags->codec_except);
 		codec_store_offer(&other_media->codecs, &flags->codec_offer, &sp->codecs);
 		if (!other_media->codecs.strip_full)
@@ -2412,7 +2413,8 @@ static void codecs_offer(struct call_media *media, struct call_media *other_medi
 		if (flags && flags->reuse_codec)
 			codec_store_populate_reuse(&media->codecs, &sp->codecs);
 		else
-			codec_store_populate(&media->codecs, &sp->codecs);
+			codec_store_populate(&media->codecs, &sp->codecs,
+					.allow_asymmetric = !!(flags && flags->allow_asymmetric_codecs));
 	}
 	if (flags) {
 		codec_store_strip(&media->codecs, &flags->codec_strip, flags->codec_except);
@@ -2428,13 +2430,15 @@ static void codecs_offer(struct call_media *media, struct call_media *other_medi
 	codec_tracker_update(&media->codecs);
 
 	// set up handlers
-	codec_handlers_update(media, other_media, .flags = flags, .sp = sp);
+	codec_handlers_update(media, other_media, .flags = flags, .sp = sp,
+			.allow_asymmetric = !!(flags && flags->allow_asymmetric_codecs));
 
 	// updating the handlers may have removed some codecs, so run update the supp codecs again
 	codec_tracker_update(&media->codecs);
 
 	// finally set up handlers again based on final results
-	codec_handlers_update(media, other_media, .flags = flags, .sp = sp, .sub = dialogue[1]);
+	codec_handlers_update(media, other_media, .flags = flags, .sp = sp, .sub = dialogue[1],
+			.allow_asymmetric = !!(flags && flags->allow_asymmetric_codecs));
 }
 
 __attribute__((nonnull(1, 2, 3, 4, 5)))
@@ -2459,7 +2463,8 @@ static void codecs_answer(struct call_media *media, struct call_media *other_med
 	else
 		codec_store_populate(&other_media->codecs, &sp->codecs,
 				.codec_set = flags->codec_set,
-				.answer_only = codec_answer_only);
+				.answer_only = codec_answer_only,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 	codec_store_strip(&other_media->codecs, &flags->codec_strip, flags->codec_except);
 	codec_store_offer(&other_media->codecs, &flags->codec_offer, &sp->codecs);
 	codec_store_check_empty(&other_media->codecs, &sp->codecs);
@@ -2467,7 +2472,7 @@ static void codecs_answer(struct call_media *media, struct call_media *other_med
 	// update callee side codec handlers again (second pass after the offer) as we
 	// might need to update some handlers, e.g. when supplemental codecs have been
 	// rejected
-	codec_handlers_update(other_media, media);
+	codec_handlers_update(other_media, media, .allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
 	// finally set up our caller side codecs
 	ilogs(codec, LOG_DEBUG, "Codec answer for " STR_FORMAT " #%u",
@@ -2476,15 +2481,18 @@ static void codecs_answer(struct call_media *media, struct call_media *other_med
 	codec_store_answer(&media->codecs, &other_media->codecs, flags);
 
 	// set up handlers
-	codec_handlers_update(media, other_media, .flags = flags, .sp = sp);
+	codec_handlers_update(media, other_media, .flags = flags, .sp = sp,
+			.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
 	// updating the handlers may have removed some codecs, so run update the supp codecs again
 	codec_tracker_update(&media->codecs);
 	codec_tracker_update(&other_media->codecs);
 
 	// finally set up handlers again based on final results
-	codec_handlers_update(media, other_media, .flags = flags, .sp = sp, .sub = dialogue[1]);
-	codec_handlers_update(other_media, media, .sub = dialogue[0]);
+	codec_handlers_update(media, other_media, .flags = flags, .sp = sp, .sub = dialogue[1],
+			.allow_asymmetric = !!flags->allow_asymmetric_codecs);
+	codec_handlers_update(other_media, media, .sub = dialogue[0],
+			.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
 	// activate audio player if needed (not done by codec_handlers_update without `flags`)
 	audio_player_activate(media);
@@ -3065,7 +3073,8 @@ int monologue_publish(struct call_monologue *ml, GQueue *streams, struct sdp_ng_
 
 		__media_init_from_flags(media, NULL, sp, flags);
 
-		codec_store_populate(&media->codecs, &sp->codecs);
+		codec_store_populate(&media->codecs, &sp->codecs,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 		if (codec_store_accept_one(&media->codecs, &flags->codec_accept, !!flags->accept_any))
 			return -1;
 
@@ -3137,7 +3146,8 @@ static int monologue_subscribe_request1(struct call_monologue *src_ml, struct ca
 
 		__media_init_from_flags(src_media, dst_media, sp, flags);
 
-		codec_store_populate(&dst_media->codecs, &src_media->codecs);
+		codec_store_populate(&dst_media->codecs, &src_media->codecs,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 		codec_store_strip(&dst_media->codecs, &flags->codec_strip, flags->codec_except);
 		codec_store_strip(&dst_media->codecs, &flags->codec_consume, flags->codec_except);
 		codec_store_strip(&dst_media->codecs, &flags->codec_mask, flags->codec_except);
@@ -3145,7 +3155,8 @@ static int monologue_subscribe_request1(struct call_monologue *src_ml, struct ca
 		codec_store_transcode(&dst_media->codecs, &flags->codec_transcode, &sp->codecs);
 		codec_store_synthesise(&dst_media->codecs, &src_media->codecs);
 
-		codec_handlers_update(dst_media, src_media, .flags = flags, .sp = sp);
+		codec_handlers_update(dst_media, src_media, .flags = flags, .sp = sp,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
 		if (!flags->inactive)
 			bf_copy(&dst_media->media_flags, MEDIA_FLAG_SEND, &src_media->media_flags, SP_FLAG_RECV);
@@ -3251,18 +3262,22 @@ int monologue_subscribe_answer(struct call_monologue *dst_ml, struct sdp_ng_flag
 		if (flags->allow_transcoding) {
 			codec_store_populate(&dst_media->codecs, &sp->codecs,
 					.codec_set = flags->codec_set,
-					.answer_only = true);
+					.answer_only = true,
+					.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 			codec_store_strip(&dst_media->codecs, &flags->codec_strip, flags->codec_except);
 			codec_store_offer(&dst_media->codecs, &flags->codec_offer, &sp->codecs);
 		}
 		else {
-			codec_store_populate(&dst_media->codecs, &sp->codecs, .answer_only = true);
+			codec_store_populate(&dst_media->codecs, &sp->codecs, .answer_only = true,
+					.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 			if (!codec_store_is_full_answer(&src_media->codecs, &dst_media->codecs))
 				return -1;
 		}
 
-		codec_handlers_update(src_media, dst_media, .flags = flags);
-		codec_handlers_update(dst_media, src_media, .flags = flags, .sp = sp, .sub = rev_cs);
+		codec_handlers_update(src_media, dst_media, .flags = flags,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
+		codec_handlers_update(dst_media, src_media, .flags = flags, .sp = sp, .sub = rev_cs,
+				.allow_asymmetric = !!flags->allow_asymmetric_codecs);
 
 		__dtls_logic(flags, dst_media, sp);
 

daemon/call_interfaces.c

@@ -1105,6 +1105,10 @@ static void call_ng_flags_flags(struct sdp_ng_flags *out, str *s, void *dummy) {
 		case CSH_LOOKUP("allow-transcoding"):
 			out->allow_transcoding = 1;
 			break;
+		case CSH_LOOKUP("allow-asymmetric-codecs"):
+		case CSH_LOOKUP("allow-asymmetric-codec"):
+			out->allow_asymmetric_codecs = 1;
+			break;
 		case CSH_LOOKUP("inject-DTMF"):
 		case CSH_LOOKUP("inject-dtmf"):
 			out->inject_dtmf = 1;

daemon/codec.c

@@ -54,6 +54,8 @@ static struct timerthread codec_timers_thread;
 
 static void rtp_payload_type_copy(struct rtp_payload_type *dst, const struct rtp_payload_type *src);
 static void codec_store_add_raw_order(struct codec_store *cs, struct rtp_payload_type *pt);
+static struct rtp_payload_type *codec_store_find_compatible(struct codec_store *cs,
+		const struct rtp_payload_type *pt);
 static void __rtp_payload_type_add_name(GHashTable *, struct rtp_payload_type *pt);
 static void codec_calc_lost(struct ssrc_ctx *ssrc, uint16_t seq);
 
@@ -351,8 +353,10 @@ static struct codec_handler *__handler_new(const struct rtp_payload_type *pt, st
 
 static void __make_passthrough(struct codec_handler *handler, int dtmf_pt, int cn_pt) {
 	__handler_shutdown(handler);
-	ilogs(codec, LOG_DEBUG, "Using passthrough handler for " STR_FORMAT " with DTMF %i, CN %i",
-			STR_FMT(&handler->source_pt.encoding_with_params), dtmf_pt, cn_pt);
+	ilogs(codec, LOG_DEBUG, "Using passthrough handler for " STR_FORMAT " (%i) with DTMF %i, CN %i",
+			STR_FMT(&handler->source_pt.encoding_with_params),
+			handler->source_pt.payload_type,
+			dtmf_pt, cn_pt);
 	if (handler->source_pt.codec_def && handler->source_pt.codec_def->dtmf)
 		handler->handler_func = handler_func_dtmf;
 	else {
@@ -640,8 +644,9 @@ static void __check_codec_list(GHashTable **supplemental_sinks, struct rtp_paylo
 		pdc = first_tc_codec;
 	if (pdc && pref_dest_codec) {
 		*pref_dest_codec = pdc;
-		ilogs(codec, LOG_DEBUG, "Default sink codec is " STR_FORMAT,
-				STR_FMT(&(*pref_dest_codec)->encoding_with_params));
+		ilogs(codec, LOG_DEBUG, "Default sink codec is " STR_FORMAT " (%i)",
+				STR_FMT(&(*pref_dest_codec)->encoding_with_params),
+				(*pref_dest_codec)->payload_type);
 	}
 }
 
@@ -1135,23 +1140,7 @@ void __codec_handlers_update(struct call_media *receiver, struct call_media *sin
 		if (!sink_pt) {
 			// no matching/identical output codec. maybe we have the same output codec,
 			// but with a different payload type or a different format?
-			GQueue *dest_codecs = g_hash_table_lookup(sink->codecs.codec_names, &pt->encoding);
-			if (dest_codecs) {
-				// the sink supports this codec - check offered formats
-				for (GList *k = dest_codecs->head; k; k = k->next) {
-					unsigned int dest_ptype = GPOINTER_TO_UINT(k->data);
-					sink_pt = g_hash_table_lookup(sink->codecs.codecs,
-							GINT_TO_POINTER(dest_ptype));
-					if (!sink_pt)
-						continue;
-					if (sink_pt->clock_rate != pt->clock_rate ||
-							sink_pt->channels != pt->channels) {
-						sink_pt = NULL;
-						continue;
-					}
-					break;
-				}
-			}
+			sink_pt = codec_store_find_compatible(&sink->codecs, pt);
 		}
 
 		if (sink_pt && !pt->codec_def->supplemental) {
@@ -1253,8 +1242,9 @@ sink_pt_fixed:;
 		// we can now decide whether we can do passthrough, or transcode
 
 		// different codecs? this will only be true for non-supplemental codecs
-		// XXX needs more intelligent fmtp matching
-		if (!rtp_payload_type_eq_nf(pt, sink_pt))
+		if (!a.allow_asymmetric && pt->payload_type != sink_pt->payload_type)
+			goto transcode;
+		if (!rtp_payload_type_fmt_eq_nf(pt, sink_pt))
 			goto transcode;
 
 		// supplemental codecs are always matched up. we want them as passthrough if
@@ -1311,8 +1301,10 @@ sink_pt_fixed:;
 			goto transcode;
 
 		// everything matches - we can do passthrough
-		ilogs(codec, LOG_DEBUG, "Sink supports codec " STR_FORMAT " for passthrough",
-				STR_FMT(&pt->encoding_with_params));
+		ilogs(codec, LOG_DEBUG, "Sink supports codec " STR_FORMAT " (%i) for passthrough (to %i)",
+				STR_FMT(&pt->encoding_with_params),
+				pt->payload_type,
+				sink_pt->payload_type);
 		__make_passthrough_gsl(handler, &passthrough_handlers, sink_dtmf_pt, sink_cn_pt,
 				use_ssrc_passthrough);
 		goto next;
@@ -4806,6 +4798,40 @@ static void codec_store_add_end(struct codec_store *cs, struct rtp_payload_type
 	codec_store_add_link(cs, pt, NULL);
 }
 
+static struct rtp_payload_type *codec_store_find_compatible_q(struct codec_store *cs, GQueue *q,
+		const struct rtp_payload_type *pt)
+{
+	if (!q)
+		return NULL;
+	for (GList *l = q->head; l; l = l->next) {
+		struct rtp_payload_type *ret = g_hash_table_lookup(cs->codecs, l->data);
+		if (rtp_payload_type_fmt_eq_compat(ret, pt))
+			return ret;
+	}
+	return NULL;
+}
+static struct rtp_payload_type *codec_store_find_compatible(struct codec_store *cs,
+		const struct rtp_payload_type *pt)
+{
+	struct rtp_payload_type *ret;
+	ret = codec_store_find_compatible_q(cs,
+			g_hash_table_lookup(cs->codec_names, &pt->encoding_with_full_params),
+			pt);
+	if (ret)
+		return ret;
+	ret = codec_store_find_compatible_q(cs,
+			g_hash_table_lookup(cs->codec_names, &pt->encoding_with_params),
+			pt);
+	if (ret)
+		return ret;
+	ret = codec_store_find_compatible_q(cs,
+			g_hash_table_lookup(cs->codec_names, &pt->encoding),
+			pt);
+	if (ret)
+		return ret;
+	return NULL;
+}
+
 void __codec_store_populate_reuse(struct codec_store *dst, struct codec_store *src, struct codec_store_args a) {
 	// start fresh
 	struct call_media *media = dst->media;
@@ -4816,6 +4842,8 @@ void __codec_store_populate_reuse(struct codec_store *dst, struct codec_store *s
 		struct rtp_payload_type *orig_pt = g_hash_table_lookup(dst->codecs,
 				GINT_TO_POINTER(pt->payload_type));
 
+		pt->reverse_payload_type = pt->payload_type;
+
 		if (orig_pt)
 			ilogs(codec, LOG_DEBUG, "Retaining codec " STR_FORMAT " (%i)",
 					STR_FMT(&pt->encoding_with_params),
@@ -4871,16 +4899,24 @@ void __codec_store_populate(struct codec_store *dst, struct codec_store *src, st
 		struct rtp_payload_type *orig_pt = g_hash_table_lookup(orig_dst.codecs,
 				GINT_TO_POINTER(pt->payload_type));
 		if (a.answer_only && !orig_pt) {
-			ilogs(codec, LOG_DEBUG, "Not adding stray answer codec " STR_FORMAT " (%i)",
-					STR_FMT(&pt->encoding_with_params),
-					pt->payload_type);
-			continue;
+			if (a.allow_asymmetric)
+				orig_pt = codec_store_find_compatible(&orig_dst, pt);
+			if (!orig_pt) {
+				ilogs(codec, LOG_DEBUG, "Not adding stray answer codec " STR_FORMAT " (%i)",
+						STR_FMT(&pt->encoding_with_params),
+						pt->payload_type);
+				continue;
+			}
 		}
 		ilogs(codec, LOG_DEBUG, "Adding codec " STR_FORMAT " (%i)",
 				STR_FMT(&pt->encoding_with_params),
 				pt->payload_type);
+
+		pt->reverse_payload_type = pt->payload_type;
+
 		if (orig_pt) {
 			// carry over existing options
+			pt->payload_type = orig_pt->payload_type;
 			pt->ptime = orig_pt->ptime;
 			pt->for_transcoding = orig_pt->for_transcoding;
 			pt->accepted = orig_pt->accepted;
@@ -5303,8 +5339,11 @@ void codec_store_answer(struct codec_store *dst, struct codec_store *src, struct
 				STR_FMT(&h->dest_pt.encoding_with_params),
 				h->dest_pt.payload_type);
 		if (!g_hash_table_lookup(dst->codecs, GINT_TO_POINTER(h->dest_pt.payload_type))) {
-			if (h->passthrough)
-				codec_store_add_end(dst, pt);
+			if (h->passthrough) {
+				struct rtp_payload_type copy = *pt;
+				copy.payload_type = pt->reverse_payload_type;
+				codec_store_add_end(dst, &copy);
+			}
 			else
 				codec_store_add_end(dst, &h->dest_pt);
 			if (!is_supp)

include/call_interfaces.h

@@ -167,6 +167,7 @@ struct sdp_ng_flags {
 	             single_codec:1,
 		     reuse_codec:1,
 		     allow_transcoding:1,
+		     allow_asymmetric_codecs:1,
 		     early_media:1,
 		     accept_any:1,
 	             inject_dtmf:1,

include/codec.h

@@ -114,6 +114,7 @@ void codec_update_all_source_handlers(struct call_monologue *ml, const struct sd
 struct codec_store_args {
 	GHashTable *codec_set;
 	bool answer_only;
+	bool allow_asymmetric;
 };
 
 __attribute__((nonnull(1)))
@@ -172,6 +173,7 @@ struct chu_args {
 	const struct sdp_ng_flags *flags;
 	const struct stream_params *sp;
 	struct call_subscription *sub;
+	bool allow_asymmetric;
 };
 #define codec_handlers_update(r, s, ...) \
 	__codec_handlers_update(r, s, (struct chu_args) {__VA_ARGS__})

lib/rtplib.c

@@ -145,8 +145,7 @@ const struct rtp_payload_type *rtp_get_rfc_codec(const str *codec) {
 }
 
 // helper function: matches only basic params, without matching payload type number
-__attribute__((nonnull(1, 2)))
-static bool rtp_payload_type_fmt_eq_nf(const struct rtp_payload_type *a, const struct rtp_payload_type *b) {
+bool rtp_payload_type_fmt_eq_nf(const struct rtp_payload_type *a, const struct rtp_payload_type *b) {
 	if (a->clock_rate != b->clock_rate)
 		return false;
 	if (a->channels != b->channels)

lib/rtplib.h

@@ -92,6 +92,7 @@ struct rtp_codec_format {
 
 struct rtp_payload_type {
 	int payload_type;
+	int reverse_payload_type;
 	str encoding_with_params; // "opus/48000/2"
 	str encoding_with_full_params; // "opus/48000/1"
 	str encoding; // "opus"
@@ -129,6 +130,9 @@ __attribute__((nonnull(1, 2)))
 bool rtp_payload_type_eq_exact(const struct rtp_payload_type *a, const struct rtp_payload_type *b);
 __attribute__((nonnull(1, 2)))
 bool rtp_payload_type_eq_compat(const struct rtp_payload_type *a, const struct rtp_payload_type *b);
+// matches only basic params but not payload type number
+__attribute__((nonnull(1, 2)))
+bool rtp_payload_type_fmt_eq_nf(const struct rtp_payload_type *a, const struct rtp_payload_type *b);
 // matches only basic params and payload type number
 __attribute__((nonnull(1, 2)))
 bool rtp_payload_type_eq_nf(const struct rtp_payload_type *, const struct rtp_payload_type *);

t/auto-daemon-tests.pl

@@ -82,6 +82,214 @@ sub stun_succ {
 
 
 
+new_call;
+
+offer('AMR asymmetric, control', {}, <<SDP);
+v=0
+o=ccs-0-615-7 61271729250917 1201132646 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.144
+b=AS:80
+b=RS:1000
+b=RR:3000
+t=0 0
+a=sendrecv
+m=audio 18918 RTP/AVP 96 97 8 98
+b=AS:80
+b=RS:362
+b=RR:1087
+a=ptime:20
+a=maxptime:40
+a=msi:mavodi-0-15b-6c6-2-ffffffff-d3c00000-6005c95738e64-171f-ffffffffffffffff-@127.0.0.1-127.0.0.1;UAG-ELL-45-108
+a=rtpmap:96 AMR/8000
+a=fmtp:96 mode-set=0,2,4,7;mode-change-period=2;mode-change-neighbor=1;mode-change-capability=2;max-red=0
+a=rtpmap:97 AMR/8000
+a=fmtp:97 mode-set=7;max-red=0
+a=rtpmap:8 PCMA/8000
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+-----------------------------------------
+v=0
+o=ccs-0-615-7 61271729250917 1201132646 IN IP4 10.104.1.81
+s=-
+c=IN IP4 203.0.113.1
+b=AS:80
+b=RS:1000
+b=RR:3000
+t=0 0
+m=audio PORT RTP/AVP 96 97 8 98
+b=AS:80
+b=RS:362
+b=RR:1087
+a=maxptime:40
+a=msi:mavodi-0-15b-6c6-2-ffffffff-d3c00000-6005c95738e64-171f-ffffffffffffffff-.0.0.1-127.0.0.1;UAG-ELL-45-108
+a=rtpmap:96 AMR/8000
+a=fmtp:96 mode-set=0,2,4,7;mode-change-period=2;mode-change-neighbor=1;mode-change-capability=2;max-red=0
+a=rtpmap:97 AMR/8000
+a=fmtp:97 mode-set=7;max-red=0
+a=rtpmap:8 PCMA/8000
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+answer('AMR asymmetric, control', {}, <<SDP);
+v=0
+o=- 4694032 4694033 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.141
+t=0 0
+a=sendrecv
+m=audio 18914 RTP/AVP 118 98
+c=IN IP4 10.104.1.141
+b=RR:1087
+b=RS:362
+a=rtpmap:118 AMR/8000
+a=fmtp:118 mode-set=0,2,4,7;mode-change-period=2;mode-change-capability=2;mode-change-neighbor=1;max-red=0
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=ptime:20
+a=maxptime:40
+-----------------------------------------
+v=0
+o=- 4694032 4694033 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.141
+t=0 0
+m=audio PORT RTP/AVP 98
+c=IN IP4 203.0.113.1
+b=RR:1087
+b=RS:362
+a=maxptime:40
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+
+new_call;
+
+offer('AMR asymmetric', {}, <<SDP);
+v=0
+o=ccs-0-615-7 61271729250917 1201132646 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.144
+b=AS:80
+b=RS:1000
+b=RR:3000
+t=0 0
+a=sendrecv
+m=audio 18918 RTP/AVP 96 97 8 98
+b=AS:80
+b=RS:362
+b=RR:1087
+a=ptime:20
+a=maxptime:40
+a=msi:mavodi-0-15b-6c6-2-ffffffff-d3c00000-6005c95738e64-171f-ffffffffffffffff-@127.0.0.1-127.0.0.1;UAG-ELL-45-108
+a=rtpmap:96 AMR/8000
+a=fmtp:96 mode-set=0,2,4,7;mode-change-period=2;mode-change-neighbor=1;mode-change-capability=2;max-red=0
+a=rtpmap:97 AMR/8000
+a=fmtp:97 mode-set=7;max-red=0
+a=rtpmap:8 PCMA/8000
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+-----------------------------------------
+v=0
+o=ccs-0-615-7 61271729250917 1201132646 IN IP4 10.104.1.81
+s=-
+c=IN IP4 203.0.113.1
+b=AS:80
+b=RS:1000
+b=RR:3000
+t=0 0
+m=audio PORT RTP/AVP 96 97 8 98
+b=AS:80
+b=RS:362
+b=RR:1087
+a=maxptime:40
+a=msi:mavodi-0-15b-6c6-2-ffffffff-d3c00000-6005c95738e64-171f-ffffffffffffffff-.0.0.1-127.0.0.1;UAG-ELL-45-108
+a=rtpmap:96 AMR/8000
+a=fmtp:96 mode-set=0,2,4,7;mode-change-period=2;mode-change-neighbor=1;mode-change-capability=2;max-red=0
+a=rtpmap:97 AMR/8000
+a=fmtp:97 mode-set=7;max-red=0
+a=rtpmap:8 PCMA/8000
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+answer('AMR asymmetric', {flags => ['allow asymmetric codecs']}, <<SDP);
+v=0
+o=- 4694032 4694033 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.141
+t=0 0
+a=sendrecv
+m=audio 18914 RTP/AVP 118 98
+c=IN IP4 10.104.1.141
+b=RR:1087
+b=RS:362
+a=rtpmap:118 AMR/8000
+a=fmtp:118 mode-set=0,2,4,7;mode-change-period=2;mode-change-capability=2;mode-change-neighbor=1;max-red=0
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=ptime:20
+a=maxptime:40
+-----------------------------------------
+v=0
+o=- 4694032 4694033 IN IP4 10.104.1.81
+s=-
+c=IN IP4 10.104.1.141
+t=0 0
+m=audio PORT RTP/AVP 118 98
+c=IN IP4 203.0.113.1
+b=RR:1087
+b=RS:362
+a=maxptime:40
+a=rtpmap:118 AMR/8000
+a=fmtp:118 mode-set=0,2,4,7;mode-change-period=2;mode-change-capability=2;mode-change-neighbor=1;max-red=0
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendrecv
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+subscribe_request('AMR asymmetric', {flags => [qw/SIPREC all/]}, <<SDP);
+v=0
+o=- SDP_VERSION IN IP4 203.0.113.1
+s=RTPE_VERSION
+t=0 0
+m=audio PORT RTP/AVP 118 98
+c=IN IP4 203.0.113.1
+a=label:1
+a=rtpmap:118 AMR/8000
+a=fmtp:118 mode-set=0,2,4,7;mode-change-period=2;mode-change-capability=2;mode-change-neighbor=1;max-red=0
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendonly
+a=rtcp:PORT
+a=ptime:20
+m=audio PORT RTP/AVP 96 98
+c=IN IP4 203.0.113.1
+a=label:0
+a=rtpmap:96 AMR/8000
+a=fmtp:96 mode-set=0,2,4,7;mode-change-period=2;mode-change-capability=2;mode-change-neighbor=1;max-red=0
+a=rtpmap:98 telephone-event/8000
+a=fmtp:98 0-15
+a=sendonly
+a=rtcp:PORT
+a=ptime:20
+SDP
+
+
+
 # inject DTMF with passthrough
 
 ($sock_a, $sock_b) = new_call([qw(198.51.100.50 3000)], [qw(198.51.100.50 3002)]);