res_pjsip contact: Lock expiration/addition of contacts

Contact expiration can occur in several places:  res_pjsip_registrar,
res_pjsip_registrar_expire, and automatically when anyone calls
ast_sip_location_retrieve_aor_contact.  At the same time, res_pjsip_registrar
may also be attempting to renew or add a contact.  Since none of this was locked
it was possible for one thread to be renewing a contact and another thread to
expire it immediately because it was working off of stale data.  This was the
casue of intermittent registration/inbound/nominal/multiple_contacts test
failures.

Now, the new named lock functionality is used to lock the aor during contact
expire and add operations and res_pjsip_registrar_expire now checks the
expiration with the lock held before deleting the contact.

ASTERISK-25885 #close
Reported-by: Josh Colp

Change-Id: I83d413c46a47796f3ab052ca3b349f21cca47059

1 files changed, 42 insertions, 2 deletions

diff --git a/res/res_pjsip/location.c b/res/res_pjsip/location.c
index 3145daca0..bc14f184b 100644
--- a/res/res_pjsip/location.c
+++ b/res/res_pjsip/location.c
@@ -27,6 +27,7 @@
 #include "include/res_pjsip_private.h"
 #include "asterisk/res_pjsip_cli.h"
 #include "asterisk/statsd.h"
+#include "asterisk/named_locks.h"
 
 /*! \brief Destructor for AOR */
 static void aor_destroy(void *obj)
@@ -168,7 +169,7 @@ struct ast_sip_contact *ast_sip_location_retrieve_first_aor_contact(const struct
 	return contact;
 }
 
-struct ao2_container *ast_sip_location_retrieve_aor_contacts(const struct ast_sip_aor *aor)
+struct ao2_container *ast_sip_location_retrieve_aor_contacts_nolock(const struct ast_sip_aor *aor)
 {
 	/* Give enough space for ^ at the beginning and ;@ at the end, since that is our object naming scheme */
 	char regex[strlen(ast_sorcery_object_get_id(aor)) + 4];
@@ -191,6 +192,24 @@ struct ao2_container *ast_sip_location_retrieve_aor_contacts(const struct ast_si
 	return contacts;
 }
 
+struct ao2_container *ast_sip_location_retrieve_aor_contacts(const struct ast_sip_aor *aor)
+{
+	struct ao2_container *contacts;
+	struct ast_named_lock *lock;
+
+	lock = ast_named_lock_get(AST_NAMED_LOCK_TYPE_RWLOCK, "aor", ast_sorcery_object_get_id(aor));
+	if (!lock) {
+		return NULL;
+	}
+
+	ao2_wrlock(lock);
+	contacts = ast_sip_location_retrieve_aor_contacts_nolock(aor);
+	ao2_unlock(lock);
+	ast_named_lock_put(lock);
+
+	return contacts;
+}
+
 void ast_sip_location_retrieve_contact_and_aor_from_list(const char *aor_list, struct ast_sip_aor **aor,
 	struct ast_sip_contact **contact)
 {
@@ -274,7 +293,7 @@ struct ast_sip_contact *ast_sip_location_retrieve_contact(const char *contact_na
 	return ast_sorcery_retrieve_by_id(ast_sip_get_sorcery(), "contact", contact_name);
 }
 
-int ast_sip_location_add_contact(struct ast_sip_aor *aor, const char *uri,
+int ast_sip_location_add_contact_nolock(struct ast_sip_aor *aor, const char *uri,
 		struct timeval expiration_time, const char *path_info, const char *user_agent,
 		struct ast_sip_endpoint *endpoint)
 {
@@ -311,6 +330,27 @@ int ast_sip_location_add_contact(struct ast_sip_aor *aor, const char *uri,
 	return ast_sorcery_create(ast_sip_get_sorcery(), contact);
 }
 
+int ast_sip_location_add_contact(struct ast_sip_aor *aor, const char *uri,
+		struct timeval expiration_time, const char *path_info, const char *user_agent,
+		struct ast_sip_endpoint *endpoint)
+{
+	int res;
+	struct ast_named_lock *lock;
+
+	lock = ast_named_lock_get(AST_NAMED_LOCK_TYPE_RWLOCK, "aor", ast_sorcery_object_get_id(aor));
+	if (!lock) {
+		return -1;
+	}
+
+	ao2_wrlock(lock);
+	res = ast_sip_location_add_contact_nolock(aor, uri, expiration_time, path_info, user_agent,
+		endpoint);
+	ao2_unlock(lock);
+	ast_named_lock_put(lock);
+
+	return res;
+}
+
 int ast_sip_location_update_contact(struct ast_sip_contact *contact)
 {
 	return ast_sorcery_update(ast_sip_get_sorcery(), contact);