Ejemplo n.º 1
0
static int register_aor_core(pjsip_rx_data *rdata,
	struct ast_sip_endpoint *endpoint,
	struct ast_sip_aor *aor,
	const char *aor_name,
	struct ao2_container *contacts)
{
	static const pj_str_t USER_AGENT = { "User-Agent", 10 };

	int added = 0, updated = 0, deleted = 0;
	pjsip_contact_hdr *contact_hdr = NULL;
	struct registrar_contact_details details = { 0, };
	pjsip_tx_data *tdata;
	RAII_VAR(struct ast_str *, path_str, NULL, ast_free);
	struct ast_sip_contact *response_contact;
	char *user_agent = NULL;
	pjsip_user_agent_hdr *user_agent_hdr;
	pjsip_expires_hdr *expires_hdr;
	pjsip_via_hdr *via_hdr;
	pjsip_via_hdr *via_hdr_last;
	char *via_addr = NULL;
	int via_port = 0;
	pjsip_cid_hdr *call_id_hdr;
	char *call_id = NULL;
	size_t alloc_size;

	/* So we don't count static contacts against max_contacts we prune them out from the container */
	ao2_callback(contacts, OBJ_NODATA | OBJ_UNLINK | OBJ_MULTIPLE, registrar_prune_static, NULL);

	if (registrar_validate_contacts(rdata, contacts, aor, &added, &updated, &deleted)) {
		/* The provided Contact headers do not conform to the specification */
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 400, NULL, NULL, NULL);
		ast_sip_report_failed_acl(endpoint, rdata, "registrar_invalid_contacts_provided");
		ast_log(LOG_WARNING, "Failed to validate contacts in REGISTER request from '%s'\n",
				ast_sorcery_object_get_id(endpoint));
		return PJ_TRUE;
	}

	if (registrar_validate_path(rdata, aor, &path_str)) {
		/* Ensure that intervening proxies did not make invalid modifications to the request */
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 420, NULL, NULL, NULL);
		ast_log(LOG_WARNING, "Invalid modifications made to REGISTER request from '%s' by intervening proxy\n",
				ast_sorcery_object_get_id(endpoint));
		return PJ_TRUE;
	}

	if ((MAX(added - deleted, 0) + (!aor->remove_existing ? ao2_container_count(contacts) : 0)) > aor->max_contacts) {
		/* Enforce the maximum number of contacts */
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 403, NULL, NULL, NULL);
		ast_sip_report_failed_acl(endpoint, rdata, "registrar_attempt_exceeds_maximum_configured_contacts");
		ast_log(LOG_WARNING, "Registration attempt from endpoint '%s' to AOR '%s' will exceed max contacts of %u\n",
				ast_sorcery_object_get_id(endpoint), aor_name, aor->max_contacts);
		return PJ_TRUE;
	}

	if (!(details.pool = pjsip_endpt_create_pool(ast_sip_get_pjsip_endpoint(), "Contact Comparison", 256, 256))) {
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 500, NULL, NULL, NULL);
		return PJ_TRUE;
	}

	user_agent_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &USER_AGENT, NULL);
	if (user_agent_hdr) {
		alloc_size = pj_strlen(&user_agent_hdr->hvalue) + 1;
		user_agent = ast_alloca(alloc_size);
		ast_copy_pj_str(user_agent, &user_agent_hdr->hvalue, alloc_size);
	}

	/* Find the first Via header */
	via_hdr = via_hdr_last = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_VIA, NULL);
	if (via_hdr) {
		/* Find the last Via header */
		while ( (via_hdr = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg,
				PJSIP_H_VIA, via_hdr->next)) != NULL) {
			via_hdr_last = via_hdr;
		}
		alloc_size = pj_strlen(&via_hdr_last->sent_by.host) + 1;
		via_addr = ast_alloca(alloc_size);
		ast_copy_pj_str(via_addr, &via_hdr_last->sent_by.host, alloc_size);
		via_port=via_hdr_last->sent_by.port;
	}

	call_id_hdr = (pjsip_cid_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CALL_ID, NULL);
	if (call_id_hdr) {
		alloc_size = pj_strlen(&call_id_hdr->id) + 1;
		call_id = ast_alloca(alloc_size);
		ast_copy_pj_str(call_id, &call_id_hdr->id, alloc_size);
	}

	/* Iterate each provided Contact header and add, update, or delete */
	while ((contact_hdr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, contact_hdr ? contact_hdr->next : NULL))) {
		int expiration;
		char contact_uri[pjsip_max_url_size];
		RAII_VAR(struct ast_sip_contact *, contact, NULL, ao2_cleanup);

		if (contact_hdr->star) {
			/* A star means to unregister everything, so do so for the possible contacts */
			ao2_callback(contacts, OBJ_NODATA | OBJ_MULTIPLE, registrar_delete_contact, (void *)aor_name);
			break;
		}

		if (!PJSIP_URI_SCHEME_IS_SIP(contact_hdr->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact_hdr->uri)) {
			/* This registrar only currently supports sip: and sips: URI schemes */
			continue;
		}

		expiration = registrar_get_expiration(aor, contact_hdr, rdata);
		details.uri = pjsip_uri_get_uri(contact_hdr->uri);
		pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, details.uri, contact_uri, sizeof(contact_uri));

		if (!(contact = ao2_callback(contacts, OBJ_UNLINK, registrar_find_contact, &details))) {
			/* If they are actually trying to delete a contact that does not exist... be forgiving */
			if (!expiration) {
				ast_verb(3, "Attempted to remove non-existent contact '%s' from AOR '%s' by request\n",
					contact_uri, aor_name);
				continue;
			}

			if (ast_sip_location_add_contact_nolock(aor, contact_uri, ast_tvadd(ast_tvnow(),
				ast_samp2tv(expiration, 1)), path_str ? ast_str_buffer(path_str) : NULL,
					user_agent, via_addr, via_port, call_id, endpoint)) {
				ast_log(LOG_ERROR, "Unable to bind contact '%s' to AOR '%s'\n",
						contact_uri, aor_name);
				continue;
			}

			ast_verb(3, "Added contact '%s' to AOR '%s' with expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_ADDED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					expiration,
					user_agent);
		} else if (expiration) {
			struct ast_sip_contact *contact_update;

			contact_update = ast_sorcery_copy(ast_sip_get_sorcery(), contact);
			if (!contact_update) {
				ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
					contact->uri, expiration);
				continue;
			}

			contact_update->expiration_time = ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1));
			contact_update->qualify_frequency = aor->qualify_frequency;
			contact_update->authenticate_qualify = aor->authenticate_qualify;
			if (path_str) {
				ast_string_field_set(contact_update, path, ast_str_buffer(path_str));
			}
			if (user_agent) {
				ast_string_field_set(contact_update, user_agent, user_agent);
			}
			if (!ast_strlen_zero(ast_config_AST_SYSTEM_NAME)) {
				ast_string_field_set(contact_update, reg_server, ast_config_AST_SYSTEM_NAME);
			}

			if (ast_sip_location_update_contact(contact_update)) {
				ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
					contact->uri, expiration);
				ast_sip_location_delete_contact(contact);
				continue;
			}
			ast_debug(3, "Refreshed contact '%s' on AOR '%s' with new expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_REFRESHED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					expiration,
					contact_update->user_agent);
			ao2_cleanup(contact_update);
		} else {
			/* We want to report the user agent that was actually in the removed contact */
			ast_sip_location_delete_contact(contact);
			ast_verb(3, "Removed contact '%s' from AOR '%s' due to request\n", contact_uri, aor_name);
			ast_test_suite_event_notify("AOR_CONTACT_REMOVED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					contact->user_agent);
		}
	}

	pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);

	/* If the AOR is configured to remove any existing contacts that have not been updated/added as a result of this REGISTER
	 * do so
	 */
	if (aor->remove_existing) {
		ao2_callback(contacts, OBJ_NODATA | OBJ_MULTIPLE, registrar_delete_contact, NULL);
	}

	/* Re-retrieve contacts.  Caller will clean up the original container. */
	contacts = ast_sip_location_retrieve_aor_contacts_nolock(aor);
	response_contact = ao2_callback(contacts, 0, NULL, NULL);

	/* Send a response containing all of the contacts (including static) that are present on this AOR */
	if (ast_sip_create_response(rdata, 200, response_contact, &tdata) != PJ_SUCCESS) {
		ao2_cleanup(response_contact);
		ao2_cleanup(contacts);
		return PJ_TRUE;
	}
	ao2_cleanup(response_contact);

	/* Add the date header to the response, some UAs use this to set their date and time */
	registrar_add_date_header(tdata);

	ao2_callback(contacts, 0, registrar_add_contact, tdata);
	ao2_cleanup(contacts);

	if ((expires_hdr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_EXPIRES, NULL))) {
		expires_hdr = pjsip_expires_hdr_create(tdata->pool, registrar_get_expiration(aor, NULL, rdata));
		pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)expires_hdr);
	}

	ast_sip_send_stateful_response(rdata, tdata, endpoint);

	return PJ_TRUE;
}
Ejemplo n.º 2
0
static int rx_task(void *data)
{
	RAII_VAR(struct rx_task_data *, task_data, data, ao2_cleanup);
	RAII_VAR(struct ao2_container *, contacts, NULL, ao2_cleanup);

	int added = 0, updated = 0, deleted = 0;
	pjsip_contact_hdr *contact_hdr = NULL;
	struct registrar_contact_details details = { 0, };
	pjsip_tx_data *tdata;
	pjsip_response_addr addr;
	const char *aor_name = ast_sorcery_object_get_id(task_data->aor);

	/* Retrieve the current contacts, we'll need to know whether to update or not */
	contacts = ast_sip_location_retrieve_aor_contacts(task_data->aor);

	/* So we don't count static contacts against max_contacts we prune them out from the container */
	ao2_callback(contacts, OBJ_NODATA | OBJ_UNLINK | OBJ_MULTIPLE, registrar_prune_static, NULL);

	if (registrar_validate_contacts(task_data->rdata, contacts, task_data->aor, &added, &updated, &deleted)) {
		/* The provided Contact headers do not conform to the specification */
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), task_data->rdata, 400, NULL, NULL, NULL);
		ast_sip_report_failed_acl(task_data->endpoint, task_data->rdata, "registrar_invalid_contacts_provided");
		ast_log(LOG_WARNING, "Failed to validate contacts in REGISTER request from '%s'\n",
				ast_sorcery_object_get_id(task_data->endpoint));
		return PJ_TRUE;
	}

	if ((MAX(added - deleted, 0) + (!task_data->aor->remove_existing ? ao2_container_count(contacts) : 0)) > task_data->aor->max_contacts) {
		/* Enforce the maximum number of contacts */
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), task_data->rdata, 403, NULL, NULL, NULL);
		ast_sip_report_failed_acl(task_data->endpoint, task_data->rdata, "registrar_attempt_exceeds_maximum_configured_contacts");
		ast_log(LOG_WARNING, "Registration attempt from endpoint '%s' to AOR '%s' will exceed max contacts of %d\n",
				ast_sorcery_object_get_id(task_data->endpoint), ast_sorcery_object_get_id(task_data->aor), task_data->aor->max_contacts);
		return PJ_TRUE;
	}

	if (!(details.pool = pjsip_endpt_create_pool(ast_sip_get_pjsip_endpoint(), "Contact Comparison", 256, 256))) {
		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), task_data->rdata, 500, NULL, NULL, NULL);
		return PJ_TRUE;
	}

	/* Iterate each provided Contact header and add, update, or delete */
	while ((contact_hdr = pjsip_msg_find_hdr(task_data->rdata->msg_info.msg, PJSIP_H_CONTACT, contact_hdr ? contact_hdr->next : NULL))) {
		int expiration;
		char contact_uri[PJSIP_MAX_URL_SIZE];
		RAII_VAR(struct ast_sip_contact *, contact, NULL, ao2_cleanup);

		if (contact_hdr->star) {
			/* A star means to unregister everything, so do so for the possible contacts */
			ao2_callback(contacts, OBJ_NODATA | OBJ_MULTIPLE, registrar_delete_contact, (void *)aor_name);
			break;
		}

		if (!PJSIP_URI_SCHEME_IS_SIP(contact_hdr->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact_hdr->uri)) {
			/* This registrar only currently supports sip: and sips: URI schemes */
			continue;
		}

		expiration = registrar_get_expiration(task_data->aor, contact_hdr, task_data->rdata);
		details.uri = pjsip_uri_get_uri(contact_hdr->uri);
		pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, details.uri, contact_uri, sizeof(contact_uri));

		if (!(contact = ao2_callback(contacts, OBJ_UNLINK, registrar_find_contact, &details))) {
			/* If they are actually trying to delete a contact that does not exist... be forgiving */
			if (!expiration) {
				ast_verb(3, "Attempted to remove non-existent contact '%s' from AOR '%s' by request\n",
					contact_uri, aor_name);
				continue;
			}

			ast_sip_location_add_contact(task_data->aor, contact_uri, ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1)));
			ast_verb(3, "Added contact '%s' to AOR '%s' with expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_ADDED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d",
					contact_uri,
					aor_name,
					expiration);
		} else if (expiration) {
			RAII_VAR(struct ast_sip_contact *, updated, ast_sorcery_copy(ast_sip_get_sorcery(), contact), ao2_cleanup);
			updated->expiration_time = ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1));
			updated->qualify_frequency = task_data->aor->qualify_frequency;
			updated->authenticate_qualify = task_data->aor->authenticate_qualify;

			ast_sip_location_update_contact(updated);
			ast_debug(3, "Refreshed contact '%s' on AOR '%s' with new expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_REFRESHED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d",
					contact_uri,
					aor_name,
					expiration);
		} else {
			ast_sip_location_delete_contact(contact);
			ast_verb(3, "Removed contact '%s' from AOR '%s' due to request\n", contact_uri, aor_name);
			ast_test_suite_event_notify("AOR_CONTACT_REMOVED",
					"Contact: %s\r\n"
					"AOR: %s",
					contact_uri,
					aor_name);
		}
	}

	pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);

	/* If the AOR is configured to remove any existing contacts that have not been updated/added as a result of this REGISTER
	 * do so
	 */
	if (task_data->aor->remove_existing) {
		ao2_callback(contacts, OBJ_NODATA | OBJ_MULTIPLE, registrar_delete_contact, NULL);
	}

	/* Update the contacts as things will probably have changed */
	ao2_cleanup(contacts);
	contacts = ast_sip_location_retrieve_aor_contacts(task_data->aor);

	/* Send a response containing all of the contacts (including static) that are present on this AOR */
	if (pjsip_endpt_create_response(ast_sip_get_pjsip_endpoint(), task_data->rdata, 200, NULL, &tdata) != PJ_SUCCESS) {
		return PJ_TRUE;
	}

	/* Add the date header to the response, some UAs use this to set their date and time */
	registrar_add_date_header(tdata);

	ao2_callback(contacts, 0, registrar_add_contact, tdata);

	if (pjsip_get_response_addr(tdata->pool, task_data->rdata, &addr) == PJ_SUCCESS) {
		pjsip_endpt_send_response(ast_sip_get_pjsip_endpoint(), &addr, tdata, NULL, NULL);
	} else {
		pjsip_tx_data_dec_ref(tdata);
	}

	return PJ_TRUE;
}
Ejemplo n.º 3
0
static void register_aor_core(pjsip_rx_data *rdata,
	struct ast_sip_endpoint *endpoint,
	struct ast_sip_aor *aor,
	const char *aor_name,
	struct ao2_container *contacts,
	struct aor_core_response *response)
{
	static const pj_str_t USER_AGENT = { "User-Agent", 10 };

	int added = 0;
	int updated = 0;
	int deleted = 0;
	int permanent = 0;
	int contact_count;
	struct ao2_container *existing_contacts = NULL;
	pjsip_contact_hdr *contact_hdr = (pjsip_contact_hdr *)&rdata->msg_info.msg->hdr;
	struct registrar_contact_details details = { 0, };
	pjsip_tx_data *tdata;
	RAII_VAR(struct ast_str *, path_str, NULL, ast_free);
	struct ast_sip_contact *response_contact;
	char *user_agent = NULL;
	pjsip_user_agent_hdr *user_agent_hdr;
	pjsip_expires_hdr *expires_hdr;
	pjsip_via_hdr *via_hdr;
	pjsip_via_hdr *via_hdr_last;
	char *via_addr = NULL;
	int via_port = 0;
	pjsip_cid_hdr *call_id_hdr;
	char *call_id = NULL;
	size_t alloc_size;

	/* We create a single pool and use it throughout this function where we need one */
	details.pool = pjsip_endpt_create_pool(ast_sip_get_pjsip_endpoint(),
		"Contact Comparison", 1024, 256);
	if (!details.pool) {
		response->code = 500;
		return;
	}

	/* If there are any permanent contacts configured on the AOR we need to take them
	 * into account when counting contacts.
	 */
	if (aor->permanent_contacts) {
		permanent = ao2_container_count(aor->permanent_contacts);
	}

	if (registrar_validate_contacts(rdata, details.pool, contacts, aor, permanent, &added, &updated, &deleted)) {
		/* The provided Contact headers do not conform to the specification */
		ast_sip_report_failed_acl(endpoint, rdata, "registrar_invalid_contacts_provided");
		ast_log(LOG_WARNING, "Failed to validate contacts in REGISTER request from '%s'\n",
				ast_sorcery_object_get_id(endpoint));
		response->code = 400;
		pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
		return;
	}

	if (registrar_validate_path(rdata, aor, &path_str)) {
		/* Ensure that intervening proxies did not make invalid modifications to the request */
		ast_log(LOG_WARNING, "Invalid modifications made to REGISTER request from '%s' by intervening proxy\n",
				ast_sorcery_object_get_id(endpoint));
		response->code = 420;
		pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
		return;
	}

	if (aor->remove_existing) {
		/* Cumulative number of contacts affected by this registration */
		contact_count = MAX(updated + added - deleted,  0);

		/* We need to keep track of only existing contacts so we can later
		 * remove them if need be.
		 */
		existing_contacts = ao2_container_alloc_list(AO2_ALLOC_OPT_LOCK_NOLOCK, 0,
			NULL, ast_sorcery_object_id_compare);
		if (!existing_contacts) {
			response->code = 500;
			pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
			return;
		}

		ao2_callback(contacts, OBJ_NODATA, registrar_add_non_permanent, existing_contacts);
	} else {
		/* Total contacts after this registration */
		contact_count = ao2_container_count(contacts) - permanent + added - deleted;
	}
	if (contact_count > aor->max_contacts) {
		/* Enforce the maximum number of contacts */
		ast_sip_report_failed_acl(endpoint, rdata, "registrar_attempt_exceeds_maximum_configured_contacts");
		ast_log(LOG_WARNING, "Registration attempt from endpoint '%s' to AOR '%s' will exceed max contacts of %u\n",
				ast_sorcery_object_get_id(endpoint), aor_name, aor->max_contacts);
		response->code = 403;
		pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);
		ao2_cleanup(existing_contacts);
		return;
	}

	user_agent_hdr = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &USER_AGENT, NULL);
	if (user_agent_hdr) {
		alloc_size = pj_strlen(&user_agent_hdr->hvalue) + 1;
		user_agent = ast_alloca(alloc_size);
		ast_copy_pj_str(user_agent, &user_agent_hdr->hvalue, alloc_size);
	}

	/* Find the first Via header */
	via_hdr = via_hdr_last = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_VIA, NULL);
	if (via_hdr) {
		/* Find the last Via header */
		while ( (via_hdr = (pjsip_via_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg,
				PJSIP_H_VIA, via_hdr->next)) != NULL) {
			via_hdr_last = via_hdr;
		}
		alloc_size = pj_strlen(&via_hdr_last->sent_by.host) + 1;
		via_addr = ast_alloca(alloc_size);
		ast_copy_pj_str(via_addr, &via_hdr_last->sent_by.host, alloc_size);
		via_port=via_hdr_last->sent_by.port;
	}

	call_id_hdr = (pjsip_cid_hdr*) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CALL_ID, NULL);
	if (call_id_hdr) {
		alloc_size = pj_strlen(&call_id_hdr->id) + 1;
		call_id = ast_alloca(alloc_size);
		ast_copy_pj_str(call_id, &call_id_hdr->id, alloc_size);
	}

	/* Iterate each provided Contact header and add, update, or delete */
	for (; (contact_hdr = (pjsip_contact_hdr *) pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, contact_hdr->next)); pj_pool_reset(details.pool)) {
		int expiration;
		char contact_uri[pjsip_max_url_size];
		RAII_VAR(struct ast_sip_contact *, contact, NULL, ao2_cleanup);

		if (contact_hdr->star) {
			/* A star means to unregister everything, so do so for the possible contacts */
			ao2_callback(contacts, OBJ_NODATA | OBJ_UNLINK | OBJ_MULTIPLE,
				registrar_delete_contact, (void *)aor_name);
			/* If we are keeping track of existing contacts for removal then, well, there is
			 * absolutely nothing left so no need to try to remove any.
			 */
			if (existing_contacts) {
				ao2_ref(existing_contacts, -1);
				existing_contacts = NULL;
			}
			break;
		}

		if (!PJSIP_URI_SCHEME_IS_SIP(contact_hdr->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact_hdr->uri)) {
			/* This registrar only currently supports sip: and sips: URI schemes */
			continue;
		}

		expiration = registrar_get_expiration(aor, contact_hdr, rdata);
		details.uri = pjsip_uri_get_uri(contact_hdr->uri);
		pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, details.uri, contact_uri, sizeof(contact_uri));

		contact = ao2_callback(contacts, OBJ_UNLINK, registrar_find_contact, &details);

		/* If a contact was returned and we need to keep track of existing contacts then it
		 * should be removed.
		 */
		if (contact && existing_contacts) {
			ao2_unlink(existing_contacts, contact);
		}

		if (!contact) {
			int prune_on_boot;

			/* If they are actually trying to delete a contact that does not exist... be forgiving */
			if (!expiration) {
				ast_verb(3, "Attempted to remove non-existent contact '%s' from AOR '%s' by request\n",
					contact_uri, aor_name);
				continue;
			}

			prune_on_boot = !ast_sip_will_uri_survive_restart(details.uri, endpoint, rdata);

			contact = ast_sip_location_create_contact(aor, contact_uri,
				ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1)),
				path_str ? ast_str_buffer(path_str) : NULL,
				user_agent, via_addr, via_port, call_id, prune_on_boot, endpoint);
			if (!contact) {
				ast_log(LOG_ERROR, "Unable to bind contact '%s' to AOR '%s'\n",
					contact_uri, aor_name);
				continue;
			}

			if (prune_on_boot) {
				const char *contact_name;
				struct contact_transport_monitor *monitor;

				/*
				 * Monitor the transport in case it gets disconnected because
				 * the contact won't be valid anymore if that happens.
				 */
				contact_name = ast_sorcery_object_get_id(contact);
				monitor = ao2_alloc_options(sizeof(*monitor) + 2 + strlen(aor_name)
					+ strlen(contact_name), NULL, AO2_ALLOC_OPT_LOCK_NOLOCK);
				if (monitor) {
					strcpy(monitor->aor_name, aor_name);/* Safe */
					monitor->contact_name = monitor->aor_name + strlen(aor_name) + 1;
					strcpy(monitor->contact_name, contact_name);/* Safe */

					ast_sip_transport_monitor_register(rdata->tp_info.transport,
						register_contact_transport_shutdown_cb, monitor);
					ao2_ref(monitor, -1);
				}
			}

			ast_verb(3, "Added contact '%s' to AOR '%s' with expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_ADDED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					expiration,
					user_agent);

			ao2_link(contacts, contact);
		} else if (expiration) {
			struct ast_sip_contact *contact_update;

			contact_update = ast_sorcery_copy(ast_sip_get_sorcery(), contact);
			if (!contact_update) {
				ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
					contact->uri, expiration);
				continue;
			}

			contact_update->expiration_time = ast_tvadd(ast_tvnow(), ast_samp2tv(expiration, 1));
			contact_update->qualify_frequency = aor->qualify_frequency;
			contact_update->authenticate_qualify = aor->authenticate_qualify;
			if (path_str) {
				ast_string_field_set(contact_update, path, ast_str_buffer(path_str));
			}
			if (user_agent) {
				ast_string_field_set(contact_update, user_agent, user_agent);
			}
			if (!ast_strlen_zero(ast_config_AST_SYSTEM_NAME)) {
				ast_string_field_set(contact_update, reg_server, ast_config_AST_SYSTEM_NAME);
			}

			if (ast_sip_location_update_contact(contact_update)) {
				ast_log(LOG_ERROR, "Failed to update contact '%s' expiration time to %d seconds.\n",
					contact->uri, expiration);
				ast_sip_location_delete_contact(contact);
				continue;
			}
			ast_debug(3, "Refreshed contact '%s' on AOR '%s' with new expiration of %d seconds\n",
				contact_uri, aor_name, expiration);
			ast_test_suite_event_notify("AOR_CONTACT_REFRESHED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"Expiration: %d\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					expiration,
					contact_update->user_agent);
			ao2_link(contacts, contact_update);
			ao2_cleanup(contact_update);
		} else {
			if (contact->prune_on_boot) {
				struct contact_transport_monitor *monitor;
				const char *contact_name =
					ast_sorcery_object_get_id(contact);

				monitor = ast_alloca(sizeof(*monitor) + 2 + strlen(aor_name)
					+ strlen(contact_name));
				strcpy(monitor->aor_name, aor_name);/* Safe */
				monitor->contact_name = monitor->aor_name + strlen(aor_name) + 1;
				strcpy(monitor->contact_name, contact_name);/* Safe */

				ast_sip_transport_monitor_unregister(rdata->tp_info.transport,
					register_contact_transport_shutdown_cb, monitor, contact_transport_monitor_matcher);
			}

			/* We want to report the user agent that was actually in the removed contact */
			ast_sip_location_delete_contact(contact);
			ast_verb(3, "Removed contact '%s' from AOR '%s' due to request\n", contact_uri, aor_name);
			ast_test_suite_event_notify("AOR_CONTACT_REMOVED",
					"Contact: %s\r\n"
					"AOR: %s\r\n"
					"UserAgent: %s",
					contact_uri,
					aor_name,
					contact->user_agent);
		}
	}

	pjsip_endpt_release_pool(ast_sip_get_pjsip_endpoint(), details.pool);

	/*
	 * If the AOR is configured to remove any contacts over max_contacts
	 * that have not been updated/added/deleted as a result of this
	 * REGISTER do so.
	 *
	 * The existing contacts container holds all contacts that were not
	 * involved in this REGISTER.
	 * The contacts container holds the current contacts of the AOR.
	 */
	if (aor->remove_existing && existing_contacts) {
		/* Total contacts after this registration */
		contact_count = ao2_container_count(existing_contacts) + updated + added;
		if (contact_count > aor->max_contacts) {
			/* Remove excess existing contacts that expire the soonest */
			remove_excess_contacts(existing_contacts, contacts, contact_count - aor->max_contacts);
		}
		ao2_ref(existing_contacts, -1);
	}

	response_contact = ao2_callback(contacts, 0, NULL, NULL);

	/* Send a response containing all of the contacts (including static) that are present on this AOR */
	if (ast_sip_create_response(rdata, 200, response_contact, &tdata) != PJ_SUCCESS) {
		ao2_cleanup(response_contact);
		ao2_cleanup(contacts);
		response->code = 500;
		return;
	}
	ao2_cleanup(response_contact);

	/* Add the date header to the response, some UAs use this to set their date and time */
	registrar_add_date_header(tdata);

	ao2_callback(contacts, 0, registrar_add_contact, tdata);

	if ((expires_hdr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_EXPIRES, NULL))) {
		expires_hdr = pjsip_expires_hdr_create(tdata->pool, registrar_get_expiration(aor, NULL, rdata));
		pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)expires_hdr);
	}

	response->tdata = tdata;
}