Merge "res_pjsip_sdp_rtp: No rtpmap for static RTP payload IDs in SDP."

4 files changed, 26 insertions, 15 deletions

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index affe937e8..6fd7e8634 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -13097,7 +13097,7 @@ static void add_codec_to_sdp(const struct sip_pvt *p,
 	/* Opus mandates 2 channels in rtpmap */
 	if (ast_format_cmp(format, ast_format_opus) == AST_FORMAT_CMP_EQUAL) {
 		ast_str_append(a_buf, 0, "a=rtpmap:%d %s/%u/2\r\n", rtp_code, mime, rate);
-	} else if ((35 <= rtp_code) || !(sip_cfg.compactheaders)) {
+	} else if ((AST_RTP_PT_LAST_STATIC < rtp_code) || !(sip_cfg.compactheaders)) {
 		ast_str_append(a_buf, 0, "a=rtpmap:%d %s/%u\r\n", rtp_code, mime, rate);
 	}
 
diff --git a/include/asterisk/rtp_engine.h b/include/asterisk/rtp_engine.h
index fa7fed8a1..55acf6529 100644
--- a/include/asterisk/rtp_engine.h
+++ b/include/asterisk/rtp_engine.h
@@ -81,6 +81,12 @@ extern "C" {
 /*! Maximum number of payload types RTP can support. */
 #define AST_RTP_MAX_PT 128
 
+/*!
+ * Last RTP payload type statically assigned, see
+ * http://www.iana.org/assignments/rtp-parameters
+ */
+#define AST_RTP_PT_LAST_STATIC 34
+
 /*! First dynamic RTP payload type */
 #define AST_RTP_PT_FIRST_DYNAMIC 96
 
diff --git a/main/rtp_engine.c b/main/rtp_engine.c
index 0a2e84fcd..82298901d 100644
--- a/main/rtp_engine.c
+++ b/main/rtp_engine.c
@@ -1426,28 +1426,31 @@ static int find_unused_payload(const struct ast_rtp_codecs *codecs)
 	 * https://tools.ietf.org/html/draft-roach-mmusic-unified-plan#section-3.2.1.2
 	 * https://tools.ietf.org/html/draft-wu-avtcore-dynamic-pt-usage#section-3
 	 */
-	res = find_unused_payload_in_range(codecs, MAX(ast_option_rtpptdynamic, 35),
+	res = find_unused_payload_in_range(
+		codecs, MAX(ast_option_rtpptdynamic, AST_RTP_PT_LAST_STATIC + 1),
 		AST_RTP_PT_LAST_REASSIGN, static_RTP_PT);
 	if (res != -1) {
 		return res;
 	}
 
-	/* Yet, reusing mappings below 35 is not supported in Asterisk because
-	 * when Compact Headers are activated, no rtpmap is send for those below
-	 * 35. If you want to use 35 and below
+	/* Yet, reusing mappings below AST_RTP_PT_LAST_STATIC (35) is not supported
+	 * in Asterisk because when Compact Headers are activated, no rtpmap is
+	 * send for those below 35. If you want to use 35 and below
 	 * A) do not use Compact Headers,
 	 * B) remove that code in chan_sip/res_pjsip, or
 	 * C) add a flag that this RTP Payload Type got reassigned dynamically
 	 *    and requires a rtpmap even with Compact Headers enabled.
 	 */
 	res = find_unused_payload_in_range(
-		codecs, MAX(ast_option_rtpptdynamic, 20), 35, static_RTP_PT);
+		codecs, MAX(ast_option_rtpptdynamic, 20),
+		AST_RTP_PT_LAST_STATIC + 1, static_RTP_PT);
 	if (res != -1) {
 		return res;
 	}
 
 	return find_unused_payload_in_range(
-		codecs, MAX(ast_option_rtpptdynamic, 0), 20, static_RTP_PT);
+		codecs, MAX(ast_option_rtpptdynamic, 0),
+		20, static_RTP_PT);
 }
 
 /*!
diff --git a/res/res_pjsip_sdp_rtp.c b/res/res_pjsip_sdp_rtp.c
index dfa6957c7..97e365c10 100644
--- a/res/res_pjsip_sdp_rtp.c
+++ b/res/res_pjsip_sdp_rtp.c
@@ -453,6 +453,7 @@ static int set_caps(struct ast_sip_session *session,
 static pjmedia_sdp_attr* generate_rtpmap_attr(struct ast_sip_session *session, pjmedia_sdp_media *media, pj_pool_t *pool,
 					      int rtp_code, int asterisk_format, struct ast_format *format, int code)
 {
+	extern pj_bool_t pjsip_use_compact_form;
 	pjmedia_sdp_rtpmap rtpmap;
 	pjmedia_sdp_attr *attr = NULL;
 	char tmp[64];
@@ -461,6 +462,11 @@ static pjmedia_sdp_attr* generate_rtpmap_attr(struct ast_sip_session *session, p
 
 	snprintf(tmp, sizeof(tmp), "%d", rtp_code);
 	pj_strdup2(pool, &media->desc.fmt[media->desc.fmt_count++], tmp);
+
+	if (rtp_code <= AST_RTP_PT_LAST_STATIC && pjsip_use_compact_form) {
+		return NULL;
+	}
+
 	rtpmap.pt = media->desc.fmt[media->desc.fmt_count - 1];
 	rtpmap.clock_rate = ast_rtp_lookup_sample_rate2(asterisk_format, format, code);
 	pj_strdup2(pool, &rtpmap.enc_name, ast_rtp_lookup_mime_subtype2(asterisk_format, format, code, options));
@@ -1260,11 +1266,9 @@ static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct as
 			continue;
 		}
 
-		if (!(attr = generate_rtpmap_attr(session, media, pool, rtp_code, 1, format, 0))) {
-			ao2_ref(format, -1);
-			continue;
+		if ((attr = generate_rtpmap_attr(session, media, pool, rtp_code, 1, format, 0))) {
+			media->attr[media->attr_count++] = attr;
 		}
-		media->attr[media->attr_count++] = attr;
 
 		if ((attr = generate_fmtp_attr(pool, format, rtp_code))) {
 			media->attr[media->attr_count++] = attr;
@@ -1293,12 +1297,10 @@ static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct as
 				continue;
 			}
 
-			if (!(attr = generate_rtpmap_attr(session, media, pool, rtp_code, 0, NULL, index))) {
-				continue;
+			if ((attr = generate_rtpmap_attr(session, media, pool, rtp_code, 0, NULL, index))) {
+				media->attr[media->attr_count++] = attr;
 			}
 
-			media->attr[media->attr_count++] = attr;
-
 			if (index == AST_RTP_DTMF) {
 				snprintf(tmp, sizeof(tmp), "%d 0-16", rtp_code);
 				attr = pjmedia_sdp_attr_create(pool, "fmtp", pj_cstr(&stmp, tmp));