Merge "res_pjsip_transport_management: Kill idle TCP connections."

res/res_pjsip_transport_management.c

@@ -32,7 +32,9 @@
 #include "asterisk/astobj2.h"
 
 /*! \brief Number of buckets for keepalive transports */
-#define KEEPALIVE_TRANSPORTS_BUCKETS 53
+#define TRANSPORTS_BUCKETS 53
+
+#define IDLE_TIMEOUT (pjsip_cfg()->tsx.td)
 
 /*! \brief The keep alive packet to send */
 static const pj_str_t keepalive_packet = { "\r\n\r\n", 4 };
@@ -40,6 +42,9 @@ static const pj_str_t keepalive_packet = { "\r\n\r\n", 4 };
 /*! \brief Global container of active transports */
 static struct ao2_container *transports;
 
+/*! \brief Scheduler context for timing out connections with no data received */
+static struct ast_sched_context *sched;
+
 /*! \brief Thread keeping things alive */
 static pthread_t keepalive_thread = AST_PTHREADT_NULL;
 
@@ -49,24 +54,26 @@ static unsigned int keepalive_interval;
 /*! \brief Existing transport manager callback that we need to invoke */
 static pjsip_tp_state_callback tpmgr_state_callback;
 
-/*! \brief Structure for transport to be kept alive */
-struct keepalive_transport {
+/*! \brief Structure for transport to be monitored */
+struct monitored_transport {
 	/*! \brief The underlying PJSIP transport */
 	pjsip_transport *transport;
+	/*! \brief Non-zero if a PJSIP request was received */
+	int sip_received;
 };
 
 /*! \brief Callback function to send keepalive */
 static int keepalive_transport_cb(void *obj, void *arg, int flags)
 {
-	struct keepalive_transport *keepalive = obj;
+	struct monitored_transport *monitored = obj;
 	pjsip_tpselector selector = {
 		.type = PJSIP_TPSELECTOR_TRANSPORT,
-		.u.transport = keepalive->transport,
+		.u.transport = monitored->transport,
 	};
 
 	pjsip_tpmgr_send_raw(pjsip_endpt_get_tpmgr(ast_sip_get_pjsip_endpoint()),
-		keepalive->transport->key.type, &selector, NULL, keepalive_packet.ptr, keepalive_packet.slen,
-		&keepalive->transport->key.rem_addr, pj_sockaddr_get_len(&keepalive->transport->key.rem_addr),
+		monitored->transport->key.type, &selector, NULL, keepalive_packet.ptr, keepalive_packet.slen,
+		&monitored->transport->key.rem_addr, pj_sockaddr_get_len(&monitored->transport->key.rem_addr),
 		NULL, NULL);
 
 	return 0;
@@ -94,32 +101,60 @@ static void *keepalive_transport_thread(void *data)
 	return NULL;
 }
 
-/*! \brief Destructor for keepalive transport */
-static void keepalive_transport_destroy(void *obj)
+static int idle_sched_cb(const void *data)
 {
-	struct keepalive_transport *keepalive = obj;
+	struct monitored_transport *keepalive = (struct monitored_transport *) data;
+	int sip_received = ast_atomic_fetchadd_int(&keepalive->sip_received, 0);
+
+	if (!sip_received) {
+		ast_log(LOG_NOTICE, "Shutting down transport '%s' since no request was received in %d seconds\n",
+				keepalive->transport->info, IDLE_TIMEOUT);
+		pjsip_transport_shutdown(keepalive->transport);
+	}
+
+	ao2_ref(keepalive, -1);
+	return 0;
+}
+
+/*! \brief Destructor for keepalive transport */
+static void monitored_transport_destroy(void *obj)
+{
+	struct monitored_transport *keepalive = obj;
 
 	pjsip_transport_dec_ref(keepalive->transport);
 }
 
 /*! \brief Callback invoked when transport changes occur */
-static void keepalive_transport_state_callback(pjsip_transport *transport, pjsip_transport_state state,
+static void monitored_transport_state_callback(pjsip_transport *transport, pjsip_transport_state state,
 	const pjsip_transport_state_info *info)
 {
-	/* We only care about connection-oriented transports */
-	if (transport->flag & PJSIP_TRANSPORT_RELIABLE) {
-		struct keepalive_transport *keepalive;
+	/* We only care about reliable transports */
+	if (PJSIP_TRANSPORT_IS_RELIABLE(transport) &&
+			(transport->dir == PJSIP_TP_DIR_INCOMING || keepalive_interval)) {
+		struct monitored_transport *monitored;
 
 		switch (state) {
 		case PJSIP_TP_STATE_CONNECTED:
-			keepalive = ao2_alloc(sizeof(*keepalive), keepalive_transport_destroy);
-			if (keepalive) {
-				keepalive->transport = transport;
-				pjsip_transport_add_ref(keepalive->transport);
-				ao2_link(transports, keepalive);
-				ao2_ref(keepalive, -1);
+			monitored = ao2_alloc(sizeof(*monitored), monitored_transport_destroy);
+			if (!monitored) {
+				break;
+			}
+			monitored->transport = transport;
+			pjsip_transport_add_ref(monitored->transport);
+			ao2_link(transports, monitored);
+			if (transport->dir == PJSIP_TP_DIR_INCOMING) {
+				/* Let the scheduler inherit the reference from allocation */
+				if (ast_sched_add_variable(sched, IDLE_TIMEOUT, idle_sched_cb, monitored, 1) < 0) {
+					ao2_unlink(transports, monitored);
+					ao2_ref(monitored, -1);
+					pjsip_transport_shutdown(transport);
+				}
+			} else {
+				/* No scheduled task, so get rid of the allocation reference */
+				ao2_ref(monitored, -1);
 			}
 			break;
+		case PJSIP_TP_STATE_SHUTDOWN:
 		case PJSIP_TP_STATE_DISCONNECTED:
 			ao2_find(transports, transport->obj_name, OBJ_SEARCH_KEY | OBJ_NODATA | OBJ_UNLINK);
 			break;
@@ -134,10 +169,10 @@ static void keepalive_transport_state_callback(pjsip_transport *transport, pjsip
 	}
 }
 
-/*! \brief Hashing function for keepalive transport */
-static int keepalive_transport_hash_fn(const void *obj, int flags)
+/*! \brief Hashing function for monitored transport */
+static int monitored_transport_hash_fn(const void *obj, int flags)
 {
-	const struct keepalive_transport *object;
+	const struct monitored_transport *object;
 	const char *key;
 
 	switch (flags & OBJ_SEARCH_MASK) {
@@ -156,11 +191,11 @@ static int keepalive_transport_hash_fn(const void *obj, int flags)
 	return ast_str_hash(key);
 }
 
-/*! \brief Comparison function for keepalive transport */
-static int keepalive_transport_cmp_fn(void *obj, void *arg, int flags)
+/*! \brief Comparison function for monitored transport */
+static int monitored_transport_cmp_fn(void *obj, void *arg, int flags)
 {
-	const struct keepalive_transport *object_left = obj;
-	const struct keepalive_transport *object_right = arg;
+	const struct monitored_transport *object_left = obj;
+	const struct monitored_transport *object_right = arg;
 	const char *right_key = arg;
 	int cmp;
 
@@ -193,7 +228,6 @@ static int keepalive_transport_cmp_fn(void *obj, void *arg, int flags)
 static void keepalive_global_loaded(const char *object_type)
 {
 	unsigned int new_interval = ast_sip_get_keep_alive_interval();
-	pjsip_tpmgr *tpmgr;
 
 	if (new_interval) {
 		keepalive_interval = new_interval;
@@ -209,28 +243,11 @@ static void keepalive_global_loaded(const char *object_type)
 		return;
 	}
 
-	transports = ao2_container_alloc(KEEPALIVE_TRANSPORTS_BUCKETS, keepalive_transport_hash_fn,
-		keepalive_transport_cmp_fn);
-	if (!transports) {
-		ast_log(LOG_ERROR, "Could not create container for transports to perform keepalive on.\n");
-		return;
-	}
-
-	tpmgr = pjsip_endpt_get_tpmgr(ast_sip_get_pjsip_endpoint());
-	if (!tpmgr) {
-		ast_log(LOG_ERROR, "No transport manager to attach keepalive functionality to.\n");
-		ao2_ref(transports, -1);
-		return;
-	}
-
 	if (ast_pthread_create(&keepalive_thread, NULL, keepalive_transport_thread, NULL)) {
 		ast_log(LOG_ERROR, "Could not create thread for sending keepalive messages.\n");
 		ao2_ref(transports, -1);
 		return;
 	}
-
-	tpmgr_state_callback = pjsip_tpmgr_get_state_cb(tpmgr);
-	pjsip_tpmgr_set_state_cb(tpmgr, &keepalive_transport_state_callback);
 }
 
 /*! \brief Observer which is used to update our interval when the global setting changes */
@@ -238,10 +255,72 @@ static struct ast_sorcery_observer keepalive_global_observer = {
 	.loaded = keepalive_global_loaded,
 };
 
+/*!
+ * \brief
+ * On incoming TCP connections, when we receive a SIP request, we mark that we have
+ * received a valid SIP request. This way, we will not shut the transport down for
+ * idleness
+ */
+static pj_bool_t idle_monitor_on_rx_request(pjsip_rx_data *rdata)
+{
+	struct monitored_transport *idle_trans;
+
+	idle_trans = ao2_find(transports, rdata->tp_info.transport->obj_name, OBJ_SEARCH_KEY);
+	if (!idle_trans) {
+		return PJ_FALSE;
+	}
+
+	ast_atomic_fetchadd_int(&idle_trans->sip_received, +1);
+	ao2_ref(idle_trans, -1);
+
+	return PJ_FALSE;
+}
+
+static pjsip_module idle_monitor_module = {
+	.name = {"idle monitor module", 19},
+	.priority = PJSIP_MOD_PRIORITY_TRANSPORT_LAYER + 3,
+	.on_rx_request = idle_monitor_on_rx_request,
+};
+
 static int load_module(void)
 {
+	pjsip_tpmgr *tpmgr;
+
 	CHECK_PJSIP_MODULE_LOADED();
 
+	transports = ao2_container_alloc(TRANSPORTS_BUCKETS, monitored_transport_hash_fn,
+		monitored_transport_cmp_fn);
+	if (!transports) {
+		ast_log(LOG_ERROR, "Could not create container for transports to perform keepalive on.\n");
+		return AST_MODULE_LOAD_DECLINE;
+	}
+
+	tpmgr = pjsip_endpt_get_tpmgr(ast_sip_get_pjsip_endpoint());
+	if (!tpmgr) {
+		ast_log(LOG_ERROR, "No transport manager to attach keepalive functionality to.\n");
+		ao2_ref(transports, -1);
+		return AST_MODULE_LOAD_DECLINE;
+	}
+
+	sched = ast_sched_context_create();
+	if (!sched) {
+		ast_log(LOG_ERROR, "Failed to create keepalive scheduler context.\n");
+		ao2_ref(transports, -1);
+		return AST_MODULE_LOAD_DECLINE;
+	}
+
+	if (ast_sched_start_thread(sched)) {
+		ast_log(LOG_ERROR, "Failed to start keepalive scheduler thread\n");
+		ast_sched_context_destroy(sched);
+		ao2_ref(transports, -1);
+		return AST_MODULE_LOAD_DECLINE;
+	}
+
+	ast_sip_register_service(&idle_monitor_module);
+
+	tpmgr_state_callback = pjsip_tpmgr_get_state_cb(tpmgr);
+	pjsip_tpmgr_set_state_cb(tpmgr, &monitored_transport_state_callback);
+
 	ast_sorcery_observer_add(ast_sip_get_sorcery(), "global", &keepalive_global_observer);
 	ast_sorcery_reload_object(ast_sip_get_sorcery(), "global");
 	ast_module_shutdown_ref(ast_module_info->self);
@@ -260,7 +339,7 @@ static int reload_module(void)
 	return 0;
 }
 
-AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP Stateful Connection Keepalive Support",
+AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP Reliable Transport Management",
 	.support_level = AST_MODULE_SUPPORT_CORE,
 	.load = load_module,
 	.reload = reload_module,