ENGDESK-27616: Support for sofia module to handle waiting for PRACK

team-telnyx · Jan 30, 2024 · ade1129 · ade1129
1 parent beecace
commit ade1129
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Showing 4 changed files with 105 additions and 0 deletions.
diff --git a/src/mod/endpoints/mod_sofia/mod_sofia.c b/src/mod/endpoints/mod_sofia/mod_sofia.c
@@ -448,6 +448,18 @@ switch_status_t sofia_on_hangup(switch_core_session_t *session)
 		return SWITCH_STATUS_SUCCESS;
 	}
 
+	if (switch_channel_var_true(channel, "apply_100rel_sync")) {
+		private_object_t *tech_pvt = switch_core_session_get_private(session);					
+		switch_mutex_lock(tech_pvt->prack_mutex);
+		if (sofia_test_flag(tech_pvt, TFLAG_PRACK_LOCK)) {
+			sofia_clear_flag(tech_pvt, TFLAG_PRACK_LOCK);
+			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG,
+					"%s Received Hangup while waiting PRACK: release PRACK lock\n", switch_channel_get_name(channel));
+			switch_thread_cond_signal(tech_pvt->prack_cond);
+		}
+		switch_mutex_unlock(tech_pvt->prack_mutex);
+	}
+
 	switch_mutex_lock(tech_pvt->sofia_mutex);
 
 
@@ -1462,6 +1474,8 @@ static switch_status_t sofia_send_dtmf(switch_core_session_t *session, const swi
 	return SWITCH_STATUS_SUCCESS;
 }
 
+#define SIP_100REL_MIN_DIFF_PROGRESS_TIME 300
+
 static switch_status_t sofia_receive_message(switch_core_session_t *session, switch_core_session_message_t *msg)
 {
 	switch_channel_t *channel = switch_core_session_get_channel(session);
@@ -1494,6 +1508,50 @@ static switch_status_t sofia_receive_message(switch_core_session_t *session, swi
 		tech_pvt->reply_contact = switch_core_session_sprintf(session, "%s;isfocus", tech_pvt->reply_contact);
 	}
 
+	// TODO
+	// Temporary solution until sofia-sip has been patch
+	// Possible race condition if 1xx and 200 OK is sent 
+	// immediately that may cause crash or will not wait
+	// for the prack before sending the final response.
+	if (switch_channel_var_true(channel, "apply_100rel_sync")) {
+		const char* message_str = "N/A";
+		switch (msg->message_id) {
+		case SWITCH_MESSAGE_INDICATE_RINGING:
+			message_str = "RINGING";
+		case SWITCH_MESSAGE_INDICATE_PROGRESS:
+			message_str = "PROGRESS";
+		case SWITCH_MESSAGE_INDICATE_ANSWER:
+			message_str = "ANSWER";
+			{
+				// PRACK timeout is also based on timer t1x64
+				// to prevent deadlock, will need to time the
+				// lock based on the value of t1x64
+				uint32_t t1x64 = tech_pvt->profile->timer_t1x64 ? tech_pvt->profile->timer_t1x64 : 32000;
+				switch_mutex_lock(tech_pvt->prack_mutex);
+				if (sofia_test_flag(tech_pvt, TFLAG_PRACK_LOCK)) {
+					switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO,
+							"%s Waiting for incoming PRACK! (Blocking %s message)\n", switch_channel_get_name(channel), message_str);
+					if (switch_thread_cond_timedwait(tech_pvt->prack_cond, tech_pvt->prack_mutex, t1x64 * 1000) == SWITCH_STATUS_TIMEOUT) {
+						switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR,
+							"%s Timeout on waiting for PRACK! (Unblock %s message)\n", switch_channel_get_name(channel), message_str);
+					} else {
+						switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO,
+							"%s Received PRACK! (Unblock %s message)\n", switch_channel_get_name(channel), message_str);
+					}
+				} else {
+					if (msg->message_id != SWITCH_MESSAGE_INDICATE_ANSWER) {
+						sofia_set_flag(tech_pvt, TFLAG_PRACK_LOCK);
+					}
+				}
+				switch_mutex_unlock(tech_pvt->prack_mutex);
+			}
+			break;
+		default:
+			break;
+		}
+	}
+
+
 	/* ones that do not need to lock sofia mutex */
 	switch (msg->message_id) {
 	case SWITCH_MESSAGE_INDICATE_KEEPALIVE:

diff --git a/src/mod/endpoints/mod_sofia/mod_sofia.h b/src/mod/endpoints/mod_sofia/mod_sofia.h
@@ -320,6 +320,7 @@ typedef enum {
 	PFLAG_TAGGED_ON_PRACK,
 	PFLAG_SDP_MEDIA_STRICT_FMT,
 	PFLAG_ALWAYS_BRIDGE_EARLY_MEDIA,
+	PFLAG_ENABLE_100REL_SYNC,
 	/* No new flags below this line */
 	PFLAG_MAX
 } PFLAGS;
@@ -373,6 +374,7 @@ typedef enum {
 	TFLAG_KEEPALIVE,
 	TFLAG_SKIP_EARLY,
 	TFLAG_100_UEPOCH_SET,
+	TFLAG_PRACK_LOCK,
 	/* No new flags below this line */
 	TFLAG_MAX
 } TFLAGS;
@@ -927,6 +929,9 @@ struct private_object {
 	switch_time_t last_audio_activity_signal_write;
 	switch_time_t last_audio_inactivity_signal_write;
 	uint8_t recovered_call_route_fixed;
+
+	switch_mutex_t *prack_mutex;
+	switch_thread_cond_t *prack_cond;
 };
 
 

diff --git a/src/mod/endpoints/mod_sofia/sofia.c b/src/mod/endpoints/mod_sofia/sofia.c
@@ -2618,6 +2618,26 @@ void sofia_event_callback(nua_event_t event,
 
 		break;
 
+	case nua_i_prack:
+		if (sofia_private) {
+			switch_core_session_t *session;
+			if ((session = switch_core_session_locate(sofia_private->uuid))) {
+				switch_channel_t *channel = switch_core_session_get_channel(session);
+				if (switch_channel_var_true(channel, "apply_100rel_sync")) {
+					private_object_t *tech_pvt = switch_core_session_get_private(session);					
+					switch_mutex_lock(tech_pvt->prack_mutex);
+					if (sofia_test_flag(tech_pvt, TFLAG_PRACK_LOCK)) {
+						sofia_clear_flag(tech_pvt, TFLAG_PRACK_LOCK);
+						switch_thread_cond_signal(tech_pvt->prack_cond);
+					}
+					switch_mutex_unlock(tech_pvt->prack_mutex);
+				}
+				switch_core_session_rwunlock(session);
+			}
+		}
+
+		break;
+
 	default:
 		break;
 
@@ -5899,6 +5919,12 @@ switch_status_t config_sofia(sofia_config_t reload, char *profile_name)
 						} else {
 							sofia_set_pflag(profile, PFLAG_DISABLE_100REL);
 						}
+					} else if (!strcasecmp(var, "enable-100rel-sync")) {
+						if (switch_true(val)) {
+							sofia_set_pflag(profile, PFLAG_ENABLE_100REL_SYNC);
+						} else {
+							sofia_clear_pflag(profile, PFLAG_ENABLE_100REL_SYNC);
+						}					
 					} else if (!strcasecmp(var, "enable-compact-headers")) {
 						if (switch_true(val)) {
 							sofia_set_pflag(profile, PFLAG_SIPCOMPACT);
@@ -11266,6 +11292,18 @@ void sofia_handle_sip_i_invite(switch_core_session_t *session, nua_t *nua, sofia
 		}
 	}
 
+	if (sip && sip->sip_supported && !sofia_test_pflag(profile, PFLAG_DISABLE_100REL)) {
+		int supported_100rel = sip_has_feature(sip->sip_supported, "100rel");
+		if (supported_100rel) {
+			const char *sync = switch_channel_get_variable(channel, "apply_100rel_sync");
+			if (sync) {
+				switch_channel_set_variable(channel, "apply_100rel_sync", switch_true(sync) ? "true" : "false");
+			} else if (sofia_test_pflag(profile, PFLAG_ENABLE_100REL_SYNC)) {
+				switch_channel_set_variable(channel, "apply_100rel_sync", "true");
+			}
+		}
+	}
+
 	if (sofia_test_media_flag(profile, SCMF_REJECT_IPV6) && sip->sip_payload && sip->sip_payload->pl_data 
 		&& switch_stristr("c=IN IP6", sip->sip_payload->pl_data)) {
 		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Reject IPv6 media address!\n");

diff --git a/src/mod/endpoints/mod_sofia/sofia_glue.c b/src/mod/endpoints/mod_sofia/sofia_glue.c
@@ -55,6 +55,8 @@ private_object_t *sofia_glue_new_pvt(switch_core_session_t *session)
 	private_object_t *tech_pvt = (private_object_t *) switch_core_session_alloc(session, sizeof(private_object_t));
 	switch_mutex_init(&tech_pvt->flag_mutex, SWITCH_MUTEX_NESTED, switch_core_session_get_pool(session));
 	switch_mutex_init(&tech_pvt->sofia_mutex, SWITCH_MUTEX_NESTED, switch_core_session_get_pool(session));
+	switch_mutex_init(&tech_pvt->prack_mutex, SWITCH_MUTEX_DEFAULT, switch_core_session_get_pool(session));
+	switch_thread_cond_create(&tech_pvt->prack_cond, switch_core_session_get_pool(session));
 	return tech_pvt;
 }
 
@@ -2393,6 +2395,8 @@ int sofia_recover_callback(switch_core_session_t *session)
 
 	switch_mutex_init(&tech_pvt->flag_mutex, SWITCH_MUTEX_NESTED, switch_core_session_get_pool(session));
 	switch_mutex_init(&tech_pvt->sofia_mutex, SWITCH_MUTEX_NESTED, switch_core_session_get_pool(session));
+	switch_mutex_init(&tech_pvt->prack_mutex, SWITCH_MUTEX_DEFAULT, switch_core_session_get_pool(session));
+	switch_thread_cond_create(&tech_pvt->prack_cond, switch_core_session_get_pool(session));
 
 	tech_pvt->mparams.remote_ip = (char *) switch_channel_get_variable(channel, "sip_network_ip");
 	tech_pvt->mparams.remote_port = atoi(switch_str_nil(switch_channel_get_variable(channel, "sip_network_port")));