res_pjsip: Fix infinite recursion when loading transports from realtime

Attempting to load a transport from realtime was forcing asterisk into an
infinite recursion loop.  The first thing transport_apply did was to do a
sorcery retrieve by id for an existing transport of the same name. For files,
this just returns the previous object from res_sorcery_config's internal
container, if any.  For realtime, the res_sourcery_realtime driver looks in the
database and finds the existing row but now it has to rehydrate it into a
sorcery object which means calling... transport_apply.  And so it goes.

The main issue with loading from realtime (apart from the loop) was that
transport stores structures and pointers directly in the ast_sip_transport
structure instead of the separate ast_transport_state structure.  This patch
separates those items into the ast_sip_transport_state structure.  The pattern
is roughly the same as res_pjsip_outbound_registration.

Although all current usages of ast_sip_transport and ast_sip_transport_state
were modified to use the new ast_sip_get_transport_state API, the original
items are left in ast_sip_transport and kept updated to maintain ABI
compatability for third-party modules.  They are marked as deprecated and
noted that they're now in ast_sip_transport_state.

ASTERISK-25606 #close
Reported-by: Martin Moučka

Change-Id: Ic7a836ea8e786e8def51fe3f8cce855ea54f5f19

include/asterisk/res_pjsip.h

@@ -54,34 +54,59 @@ struct pjsip_tpfactory;
 struct pjsip_tls_setting;
 struct pjsip_tpselector;
 
+/*! \brief Maximum number of ciphers supported for a TLS transport */
+#define SIP_TLS_MAX_CIPHERS 64
+
 /*!
  * \brief Structure for SIP transport information
  */
 struct ast_sip_transport_state {
 	/*! \brief Transport itself */
 	struct pjsip_transport *transport;
-
 	/*! \brief Transport factory */
 	struct pjsip_tpfactory *factory;
+	/*!
+	 * Transport id
+	 * \since 13.8.0
+	 */
+	char *id;
+	/*!
+	 * Transport type
+	 * \since 13.8.0
+	 */
+	enum ast_transport type;
+	/*!
+	 * Address and port to bind to
+	 * \since 13.8.0
+	 */
+	pj_sockaddr host;
+	/*!
+	 * TLS settings
+	 * \since 13.8.0
+	 */
+	pjsip_tls_setting tls;
+	/*!
+	 * Configured TLS ciphers
+	 * \since 13.8.0
+	 */
+	pj_ssl_cipher ciphers[SIP_TLS_MAX_CIPHERS];
+	/*!
+	 * Optional local network information, used for NAT purposes
+	 * \since 13.8.0
+	 */
+	struct ast_ha *localnet;
+	/*!
+	 * DNS manager for refreshing the external address
+	 * \since 13.8.0
+	 */
+	struct ast_dnsmgr_entry *external_address_refresher;
+	/*!
+	 * Optional external address information
+	 * \since 13.8.0
+	 */
+	struct ast_sockaddr external_address;
 };
 
-#define SIP_SORCERY_DOMAIN_ALIAS_TYPE "domain_alias"
-
-/*!
- * Details about a SIP domain alias
- */
-struct ast_sip_domain_alias {
-	/*! Sorcery object details */
-	SORCERY_OBJECT(details);
-	AST_DECLARE_STRING_FIELDS(
-		/*! Domain to be aliased to */
-		AST_STRING_FIELD(domain);
-	);
-};
-
-/*! \brief Maximum number of ciphers supported for a TLS transport */
-#define SIP_TLS_MAX_CIPHERS 64
-
 /*
  * \brief Transport to bind to
  */
@@ -108,23 +133,51 @@ struct ast_sip_transport {
 		);
 	/*! Type of transport */
 	enum ast_transport type;
-	/*! Address and port to bind to */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.8.0 deprecated
+	 * Address and port to bind to
+	 */
 	pj_sockaddr host;
 	/*! Number of simultaneous asynchronous operations */
 	unsigned int async_operations;
 	/*! Optional external port for signaling */
 	unsigned int external_signaling_port;
-	/*! TLS settings */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.7.1 deprecated
+	 * TLS settings
+	 */
 	pjsip_tls_setting tls;
-	/*! Configured TLS ciphers */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.7.1 deprecated
+	 * Configured TLS ciphers
+	 */
 	pj_ssl_cipher ciphers[SIP_TLS_MAX_CIPHERS];
-	/*! Optional local network information, used for NAT purposes */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.7.1 deprecated
+	 * Optional local network information, used for NAT purposes
+	 */
 	struct ast_ha *localnet;
-	/*! DNS manager for refreshing the external address */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.7.1 deprecated
+	 * DNS manager for refreshing the external address
+	 */
 	struct ast_dnsmgr_entry *external_address_refresher;
-	/*! Optional external address information */
+	/*!
+	 * \deprecated Moved to ast_sip_transport_state
+	 * \version 13.7.1 deprecated
+	 * Optional external address information
+	 */
 	struct ast_sockaddr external_address;
-	/*! Transport state information */
+	/*!
+	 * \deprecated
+	 * \version 13.7.1 deprecated
+	 * Transport state information
+	 */
 	struct ast_sip_transport_state *state;
 	/*! QOS DSCP TOS bits */
 	unsigned int tos;
@@ -134,6 +187,20 @@ struct ast_sip_transport {
 	int write_timeout;
 };
 
+#define SIP_SORCERY_DOMAIN_ALIAS_TYPE "domain_alias"
+
+/*!
+ * Details about a SIP domain alias
+ */
+struct ast_sip_domain_alias {
+	/*! Sorcery object details */
+	SORCERY_OBJECT(details);
+	AST_DECLARE_STRING_FIELDS(
+		/*! Domain to be aliased to */
+		AST_STRING_FIELD(domain);
+	);
+};
+
 /*!
  * \brief Structure for SIP nat hook information
  */
@@ -2172,4 +2239,25 @@ const char *ast_sip_get_host_ip_string(int af);
  */
 long ast_sip_threadpool_queue_size(void);
 
+/*!
+ * \brief Retrieve transport state
+ * \since 13.7.1
+ *
+ * @param transport_id
+ * @returns transport_state
+ *
+ * \note ao2_cleanup(...) or ao2_ref(...,  -1) must be called on the returned object
+ */
+struct ast_sip_transport_state *ast_sip_get_transport_state(const char *transport_id);
+
+/*!
+ * \brief Retrieves all transport states
+ * \since 13.7.1
+ *
+ * @returns ao2_container
+ *
+ * \note ao2_cleanup(...) or ao2_ref(...,  -1) must be called on the returned object
+ */
+struct ao2_container *ast_sip_get_transport_states(void);
+
 #endif /* _RES_PJSIP_H */