TT#14008 don't accept stray answer codecs that were not offered

Special handling for codec lists that were received as part of an
answer: If the list includes a codec that was not offered, ignore that
codec. This prevents transcoders from being set up that were not
requested.

This brought to light some tests that were actually broken.

Change-Id: Iac71056ec5e10b5de5567917974f2c4e0261eb0c

daemon/call.c

@@ -2347,9 +2347,11 @@ void codecs_offer_answer(struct call_media *media, struct call_media *other_medi
 				other_media->index);
 		if (flags) {
 			if (flags->reuse_codec)
-				codec_store_populate_reuse(&other_media->codecs, &sp->codecs, flags->codec_set);
+				codec_store_populate_reuse(&other_media->codecs, &sp->codecs, flags->codec_set,
+						false);
 			else
-				codec_store_populate(&other_media->codecs, &sp->codecs, flags->codec_set);
+				codec_store_populate(&other_media->codecs, &sp->codecs, flags->codec_set,
+						false);
 			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)
@@ -2359,7 +2361,8 @@ void codecs_offer_answer(struct call_media *media, struct call_media *other_medi
 			codec_store_accept(&other_media->codecs, &flags->codec_consume, &sp->codecs);
 			codec_store_track(&other_media->codecs, &flags->codec_mask);
 		} else
-			codec_store_populate(&other_media->codecs, &sp->codecs, NULL);
+			codec_store_populate(&other_media->codecs, &sp->codecs, NULL,
+					false);
 
 		// we don't update the answerer side if the offer is not RTP but is going
 		// to RTP (i.e. T.38 transcoding) - instead we leave the existing codec list
@@ -2374,9 +2377,9 @@ void codecs_offer_answer(struct call_media *media, struct call_media *other_medi
 					STR_FMT(&media->monologue->tag),
 					media->index);
 			if (flags && flags->reuse_codec)
-				codec_store_populate_reuse(&media->codecs, &sp->codecs, NULL);
+				codec_store_populate_reuse(&media->codecs, &sp->codecs, NULL, false);
 			else
-				codec_store_populate(&media->codecs, &sp->codecs, NULL);
+				codec_store_populate(&media->codecs, &sp->codecs, NULL, false);
 		}
 		if (flags) {
 			codec_store_strip(&media->codecs, &flags->codec_strip, flags->codec_except);
@@ -2406,9 +2409,9 @@ void codecs_offer_answer(struct call_media *media, struct call_media *other_medi
 				STR_FMT(&other_media->monologue->tag),
 				other_media->index);
 		if (flags->reuse_codec)
-			codec_store_populate_reuse(&other_media->codecs, &sp->codecs, flags->codec_set);
+			codec_store_populate_reuse(&other_media->codecs, &sp->codecs, flags->codec_set, true);
 		else
-			codec_store_populate(&other_media->codecs, &sp->codecs, flags->codec_set);
+			codec_store_populate(&other_media->codecs, &sp->codecs, flags->codec_set, true);
 		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);
@@ -2951,7 +2954,7 @@ 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, NULL);
+		codec_store_populate(&media->codecs, &sp->codecs, NULL, false);
 		if (codec_store_accept_one(&media->codecs, &flags->codec_accept, flags->accept_any ? true : false))
 			return -1;
 
@@ -3021,7 +3024,7 @@ static int monologue_subscribe_request1(struct call_monologue *src_ml, struct ca
 		if (__media_init_from_flags(src_media, dst_media, sp, flags) == 1)
 			continue;
 
-		codec_store_populate(&dst_media->codecs, &src_media->codecs, NULL);
+		codec_store_populate(&dst_media->codecs, &src_media->codecs, NULL, false);
 		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);
@@ -3121,12 +3124,12 @@ int monologue_subscribe_answer(struct call_monologue *dst_ml, struct sdp_ng_flag
 			continue;
 
 		if (flags && flags->allow_transcoding) {
-			codec_store_populate(&dst_media->codecs, &sp->codecs, flags->codec_set);
+			codec_store_populate(&dst_media->codecs, &sp->codecs, flags->codec_set, true);
 			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, NULL);
+			codec_store_populate(&dst_media->codecs, &sp->codecs, NULL, true);
 			if (!codec_store_is_full_answer(&src_media->codecs, &dst_media->codecs))
 				return -1;
 		}

daemon/codec.c

@@ -4189,7 +4189,9 @@ static void codec_store_add_end(struct codec_store *cs, struct rtp_payload_type
 	codec_store_add_link(cs, pt, NULL);
 }
 
-void codec_store_populate_reuse(struct codec_store *dst, struct codec_store *src, GHashTable *codec_set) {
+void codec_store_populate_reuse(struct codec_store *dst, struct codec_store *src, GHashTable *codec_set,
+		bool answer_only)
+{
 	// start fresh
 	struct call_media *media = dst->media;
 	struct call *call = media ? media->call : NULL;
@@ -4198,13 +4200,23 @@ void codec_store_populate_reuse(struct codec_store *dst, struct codec_store *src
 		struct rtp_payload_type *pt = l->data;
 		struct rtp_payload_type *orig_pt = g_hash_table_lookup(dst->codecs,
 				GINT_TO_POINTER(pt->payload_type));
-		ilogs(codec, LOG_DEBUG, "Adding codec " STR_FORMAT " (%i)",
-				STR_FMT(&pt->encoding_with_params),
-				pt->payload_type);
-				
-		if (!orig_pt) {
-			__codec_options_set(call, pt, codec_set);
-			codec_store_add_end(dst, pt);
+
+		if (orig_pt)
+			ilogs(codec, LOG_DEBUG, "Retaining codec " STR_FORMAT " (%i)",
+					STR_FMT(&pt->encoding_with_params),
+					pt->payload_type);
+		else {
+			if (!answer_only) {
+				ilogs(codec, LOG_DEBUG, "Adding codec " STR_FORMAT " (%i) to end of list",
+						STR_FMT(&pt->encoding_with_params),
+						pt->payload_type);
+				__codec_options_set(call, pt, codec_set);
+				codec_store_add_end(dst, pt);
+			}
+			else
+				ilogs(codec, LOG_DEBUG, "Not adding stray answer codec " STR_FORMAT " (%i)",
+						STR_FMT(&pt->encoding_with_params),
+						pt->payload_type);
 		}
 	}
 	if(dst->codec_prefs.head){
@@ -4228,10 +4240,12 @@ void codec_store_check_empty(struct codec_store *dst, struct codec_store *src) {
 	ilog(LOG_WARN, "Usage error: List of codecs empty. Restoring original list of codecs. "
 			"Results may be unexpected.");
 
-	codec_store_populate(dst, src, NULL);
+	codec_store_populate(dst, src, NULL, false);
 }
 
-void codec_store_populate(struct codec_store *dst, struct codec_store *src, GHashTable *codec_set) {
+void codec_store_populate(struct codec_store *dst, struct codec_store *src, GHashTable *codec_set,
+		bool answer_only)
+{
 	// start fresh
 	struct codec_store orig_dst;
 	codec_store_move(&orig_dst, dst);
@@ -4243,6 +4257,12 @@ void codec_store_populate(struct codec_store *dst, struct codec_store *src, GHas
 		struct rtp_payload_type *pt = l->data;
 		struct rtp_payload_type *orig_pt = g_hash_table_lookup(orig_dst.codecs,
 				GINT_TO_POINTER(pt->payload_type));
+		if (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;
+		}
 		ilogs(codec, LOG_DEBUG, "Adding codec " STR_FORMAT " (%i)",
 				STR_FMT(&pt->encoding_with_params),
 				pt->payload_type);

include/codec.h

@@ -94,8 +94,8 @@ void codec_update_all_handlers(struct call_monologue *ml);
 
 void codec_store_cleanup(struct codec_store *cs);
 void codec_store_init(struct codec_store *cs, struct call_media *);
-void codec_store_populate(struct codec_store *, struct codec_store *, GHashTable *);
-void codec_store_populate_reuse(struct codec_store *, struct codec_store *, GHashTable *);
+void codec_store_populate(struct codec_store *, struct codec_store *, GHashTable *, bool answer_only);
+void codec_store_populate_reuse(struct codec_store *, struct codec_store *, GHashTable *, bool answer_only);
 void codec_store_add_raw(struct codec_store *cs, struct rtp_payload_type *pt);
 void codec_store_strip(struct codec_store *, GQueue *strip, GHashTable *except);
 void codec_store_offer(struct codec_store *, GQueue *, struct codec_store *);

t/auto-daemon-tests.pl

@@ -5693,9 +5693,9 @@ o=Z 58440449 0 IN IP4 192.168.1.1
 s=Z
 c=IN IP4 192.168.1.1
 t=0 0
-m=audio 8000 RTP/AVP 96 97
-a=rtpmap:96 opus/48000
-a=rtpmap:97 telephone-event/48000
+m=audio 8000 RTP/AVP 97 102
+a=rtpmap:97 opus/48000
+a=rtpmap:102 telephone-event/48000
 a=sendrecv
 --------------------------------------
 v=0

t/test-transcode.c

@@ -1473,7 +1473,7 @@ int main(void) {
 	sdp_pt(0, PCMU, 8000);
 	sdp_pt(8, PCMA, 8000);
 	answer();
-	expect(B, "7/PCMA/8000 0/PCMU/8000 8/PCMA/8000");
+	expect(B, "0/PCMU/8000 8/PCMA/8000");
 	sdp_pt(0, PCMU, 8000);
 	sdp_pt(8, PCMA, 8000);
 	sdp_pt(9, PCMA, 8000);
@@ -1483,7 +1483,7 @@ int main(void) {
 	sdp_pt(0, PCMU, 8000);
 	sdp_pt(8, PCMA, 8000);
 	answer();
-	expect(B, "7/PCMA/8000 0/PCMU/8000 8/PCMA/8000");
+	expect(B, "0/PCMU/8000 8/PCMA/8000");
 	end();
 
 	start();