pjsip: Support dual stack automatically.

This change adds support for dual stack automatically. No
configuration is required and the IP address and version
in the SIP messages and SDP will be automatically changed
based on the transport over which the message is being
sent. RTP usage has also been changed to listen on both
IPv4 and IPv6 simultaneously to allow media to flow, and
to allow ICE support on both simultaneously. This also
allows failover between IPv6 and IPv4 to work as expected.

ASTERISK-26309 #close

Change-Id: I235a421d8f9a326606d861b449fa6fe3a030572d

1 files changed, 10 insertions, 14 deletions

diff --git a/res/res_pjsip_sdp_rtp.c b/res/res_pjsip_sdp_rtp.c
index 68d5fdb56..a69aa1a74 100644
--- a/res/res_pjsip_sdp_rtp.c
+++ b/res/res_pjsip_sdp_rtp.c
@@ -59,11 +59,8 @@ ASTERISK_REGISTER_FILE()
 /*! \brief Scheduler for RTCP purposes */
 static struct ast_sched_context *sched;
 
-/*! \brief Address for IPv4 RTP */
-static struct ast_sockaddr address_ipv4;
-
-/*! \brief Address for IPv6 RTP */
-static struct ast_sockaddr address_ipv6;
+/*! \brief Address for RTP */
+static struct ast_sockaddr address_rtp;
 
 static const char STR_AUDIO[] = "audio";
 static const int FD_AUDIO = 0;
@@ -173,11 +170,11 @@ static int rtp_check_timeout(const void *data)
 }
 
 /*! \brief Internal function which creates an RTP instance */
-static int create_rtp(struct ast_sip_session *session, struct ast_sip_session_media *session_media, unsigned int ipv6)
+static int create_rtp(struct ast_sip_session *session, struct ast_sip_session_media *session_media)
 {
 	struct ast_rtp_engine_ice *ice;
 	struct ast_sockaddr temp_media_address;
-	struct ast_sockaddr *media_address =  ipv6 ? &address_ipv6 : &address_ipv4;
+	struct ast_sockaddr *media_address =  &address_rtp;
 
 	if (session->endpoint->media.bind_rtp_to_media_address && !ast_strlen_zero(session->endpoint->media.address)) {
 		ast_sockaddr_parse(&temp_media_address, session->endpoint->media.address, 0);
@@ -903,7 +900,7 @@ static int negotiate_incoming_sdp_stream(struct ast_sip_session *session, struct
 	}
 
 	/* Using the connection information create an appropriate RTP instance */
-	if (!session_media->rtp && create_rtp(session, session_media, ast_sockaddr_is_ipv6(addrs))) {
+	if (!session_media->rtp && create_rtp(session, session_media)) {
 		return -1;
 	}
 
@@ -1055,7 +1052,6 @@ static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct as
 	pj_pool_t *pool = session->inv_session->pool_prov;
 	static const pj_str_t STR_IN = { "IN", 2 };
 	static const pj_str_t STR_IP4 = { "IP4", 3};
-	static const pj_str_t STR_IP6 = { "IP6", 3};
 	static const pj_str_t STR_SENDRECV = { "sendrecv", 8 };
 	static const pj_str_t STR_SENDONLY = { "sendonly", 8 };
 	pjmedia_sdp_media *media;
@@ -1079,7 +1075,7 @@ static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct as
 	    (!use_override_prefs && !ast_format_cap_has_type(session->endpoint->media.codecs, media_type))) {
 		/* If no type formats are configured don't add a stream */
 		return 0;
-	} else if (!session_media->rtp && create_rtp(session, session_media, session->endpoint->media.rtp.ipv6)) {
+	} else if (!session_media->rtp && create_rtp(session, session_media)) {
 		return -1;
 	}
 
@@ -1120,7 +1116,8 @@ static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct as
 	}
 
 	media->conn->net_type = STR_IN;
-	media->conn->addr_type = session->endpoint->media.rtp.ipv6 ? STR_IP6 : STR_IP4;
+	/* Connection information will be updated by the multihomed module */
+	media->conn->addr_type = STR_IP4;
 	pj_strdup2(pool, &media->conn->addr, hostip);
 	ast_rtp_instance_get_local_address(session_media->rtp, &addr);
 	media->desc.port = direct_media_enabled ? ast_sockaddr_port(&session_media->direct_media_addr) : (pj_uint16_t) ast_sockaddr_port(&addr);
@@ -1257,7 +1254,7 @@ static int apply_negotiated_sdp_stream(struct ast_sip_session *session, struct a
 	}
 
 	/* Create an RTP instance if need be */
-	if (!session_media->rtp && create_rtp(session, session_media, session->endpoint->media.rtp.ipv6)) {
+	if (!session_media->rtp && create_rtp(session, session_media)) {
 		return -1;
 	}
 
@@ -1493,8 +1490,7 @@ static int load_module(void)
 {
 	CHECK_PJSIP_SESSION_MODULE_LOADED();
 
-	ast_sockaddr_parse(&address_ipv4, "0.0.0.0", 0);
-	ast_sockaddr_parse(&address_ipv6, "::", 0);
+	ast_sockaddr_parse(&address_rtp, "::", 0);
 
 	if (!(sched = ast_sched_context_create())) {
 		ast_log(LOG_ERROR, "Unable to create scheduler context.\n");