res_pjsip_mwi: Add voicemail extension and mwi_subscribe_replaces_unsolicited

res_pjsip_mwi was missing the chan_sip "vmexten" functionality which adds
the Message-Account header to the MWI NOTIFY.  Also, specifying mailboxes
on endpoints for unsolicited mwi and on aors for subscriptions required
that the admin know in advance which the client wanted.  If you specified
mailboxes on the endpoint, subscriptions were rejected even if you also
specified mailboxes on the aor.

Voicemail extension:
* Added a global default_voicemail_extension which defaults to "".
* Added voicemail_extension to both endpoint and aor.
* Added ast_sip_subscription_get_dialog for support.
* Added ast_sip_subscription_get_sip_uri for support.

When an unsolicited NOTIFY is constructed, the From header is parsed, the
voicemail extension from the endpoint is substituted for the user, and the
result placed in the Message-Account field in the body.

When a subscribed NOTIFY is constructed, the subscription dialog local uri
is parsed, the voicemail_extension from the aor (looked up from the
subscription resource name) is substituted for the user, and the result
placed in the Message-Account field in the body.

If no voicemail extension was defined, the Message-Account field is not added
to the NOTIFY body.

mwi_subscribe_replaces_unsolicited:
* Added mwi_subscribe_replaces_unsolicited to endpoint.

The previous behavior was to reject a subscribe if a previous internal
subscription for unsolicited MWI was found for the mailbox.  That remains the
default.  However, if there are mailboxes also set on the aor and the client
subscribes and mwi_subscribe_replaces_unsolicited is set, the existing internal
subscription is removed and replaced with the external subscription.  This
allows an admin to configure mailboxes on both the endpoint and aor and allows
the client to select which to use.

ASTERISK-25865 #close
Reported-by: Ross Beer

Change-Id: Ic15a9415091760539c7134a5ba3dc4a6a1217cea

1 files changed, 96 insertions, 34 deletions

diff --git a/res/res_pjsip_mwi.c b/res/res_pjsip_mwi.c
index be38b44c1..bb8f004e3 100644
--- a/res/res_pjsip_mwi.c
+++ b/res/res_pjsip_mwi.c
@@ -42,6 +42,8 @@
 struct mwi_subscription;
 static struct ao2_container *unsolicited_mwi;
 
+static char *default_voicemail_extension;
+
 #define STASIS_BUCKETS 13
 #define MWI_BUCKETS 53
 
@@ -326,11 +328,30 @@ static int get_message_count(void *obj, void *arg, int flags)
 	return 0;
 }
 
+static void set_voicemail_extension(pj_pool_t *pool, pjsip_sip_uri *local_uri,
+	struct ast_sip_message_accumulator *counter, const char *voicemail_extension)
+{
+	pjsip_sip_uri *account_uri;
+	const char *vm_exten;
+
+	if (ast_strlen_zero(voicemail_extension)) {
+		vm_exten = default_voicemail_extension;
+	} else {
+		vm_exten = voicemail_extension;
+	}
+
+	if (!ast_strlen_zero(vm_exten)) {
+		account_uri = pjsip_uri_clone(pool, local_uri);
+		pj_strdup2(pool, &account_uri->user, vm_exten);
+		pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, account_uri, counter->message_account, sizeof(counter->message_account));
+	}
+}
+
 struct unsolicited_mwi_data {
 	struct mwi_subscription *sub;
 	struct ast_sip_endpoint *endpoint;
 	pjsip_evsub_state state;
-	const struct ast_sip_body *body;
+	struct ast_sip_message_accumulator *counter;
 };
 
 static int send_unsolicited_mwi_notify_to_contact(void *obj, void *arg, int flags)
@@ -339,27 +360,50 @@ static int send_unsolicited_mwi_notify_to_contact(void *obj, void *arg, int flag
 	struct mwi_subscription *sub = mwi_data->sub;
 	struct ast_sip_endpoint *endpoint = mwi_data->endpoint;
 	pjsip_evsub_state state = mwi_data->state;
-	const struct ast_sip_body *body = mwi_data->body;
 	struct ast_sip_contact *contact = obj;
 	const char *state_name;
 	pjsip_tx_data *tdata;
 	pjsip_sub_state_hdr *sub_state;
 	pjsip_event_hdr *event;
+	pjsip_from_hdr *from;
+	pjsip_sip_uri *from_uri;
 	const pjsip_hdr *allow_events = pjsip_evsub_get_allow_events_hdr(NULL);
+	struct ast_sip_body body;
+	struct ast_str *body_text;
+	struct ast_sip_body_data body_data = {
+		.body_type = AST_SIP_MESSAGE_ACCUMULATOR,
+		.body_data = mwi_data->counter,
+	};
 
 	if (ast_sip_create_request("NOTIFY", NULL, endpoint, NULL, contact, &tdata)) {
 		ast_log(LOG_WARNING, "Unable to create unsolicited NOTIFY request to endpoint %s URI %s\n", sub->id, contact->uri);
 		return 0;
 	}
 
-	if (!ast_strlen_zero(endpoint->subscription.mwi.fromuser)) {
-		pjsip_fromto_hdr *from = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_FROM, NULL);
-		pjsip_name_addr *from_name_addr = (pjsip_name_addr *) from->uri;
-		pjsip_sip_uri *from_uri = pjsip_uri_get_uri(from_name_addr->uri);
+	body.type = MWI_TYPE;
+	body.subtype = MWI_SUBTYPE;
+	body_text = ast_str_create(64);
+	if (!body_text) {
+		return 0;
+	}
 
+	from = PJSIP_MSG_FROM_HDR(tdata->msg);
+	from_uri = pjsip_uri_get_uri(from->uri);
+
+	if (!ast_strlen_zero(endpoint->subscription.mwi.fromuser)) {
 		pj_strdup2(tdata->pool, &from_uri->user, endpoint->subscription.mwi.fromuser);
 	}
 
+	set_voicemail_extension(tdata->pool, from_uri, mwi_data->counter, endpoint->subscription.mwi.voicemail_extension);
+
+	if (ast_sip_pubsub_generate_body_content(body.type, body.subtype, &body_data, &body_text)) {
+		ast_log(LOG_WARNING, "Unable to generate SIP MWI NOTIFY body.\n");
+		ast_free(body_text);
+		return 0;
+	}
+
+	body.body_text = ast_str_buffer(body_text);
+
 	switch (state) {
 	case PJSIP_EVSUB_STATE_ACTIVE:
 		state_name = "active";
@@ -379,9 +423,11 @@ static int send_unsolicited_mwi_notify_to_contact(void *obj, void *arg, int flag
 	pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr *) event);
 
 	pjsip_msg_add_hdr(tdata->msg, pjsip_hdr_shallow_clone(tdata->pool, allow_events));
-	ast_sip_add_body(tdata, body);
+	ast_sip_add_body(tdata, &body);
 	ast_sip_send_request(tdata, NULL, endpoint, NULL, NULL);
 
+	ast_free(body_text);
+
 	return 0;
 }
 
@@ -392,12 +438,6 @@ static void send_unsolicited_mwi_notify(struct mwi_subscription *sub,
 				"endpoint", sub->id), ao2_cleanup);
 	char *endpoint_aors;
 	char *aor_name;
-	struct ast_sip_body body;
-	struct ast_str *body_text;
-	struct ast_sip_body_data body_data = {
-		.body_type = AST_SIP_MESSAGE_ACCUMULATOR,
-		.body_data = counter,
-	};
 
 	if (!endpoint) {
 		ast_log(LOG_WARNING, "Unable to send unsolicited MWI to %s because endpoint does not exist\n",
@@ -410,23 +450,6 @@ static void send_unsolicited_mwi_notify(struct mwi_subscription *sub,
 		return;
 	}
 
-	body.type = MWI_TYPE;
-	body.subtype = MWI_SUBTYPE;
-
-	body_text = ast_str_create(64);
-
-	if (!body_text) {
-		return;
-	}
-
-	if (ast_sip_pubsub_generate_body_content(body.type, body.subtype, &body_data, &body_text)) {
-		ast_log(LOG_WARNING, "Unable to generate SIP MWI NOTIFY body.\n");
-		ast_free(body_text);
-		return;
-	}
-
-	body.body_text = ast_str_buffer(body_text);
-
 	endpoint_aors = ast_strdupa(endpoint->aors);
 
 	ast_debug(5, "Sending unsolicited MWI NOTIFY to endpoint %s, new messages: %d, old messages: %d\n",
@@ -438,7 +461,7 @@ static void send_unsolicited_mwi_notify(struct mwi_subscription *sub,
 		struct unsolicited_mwi_data mwi_data = {
 			.sub = sub,
 			.endpoint = endpoint,
-			.body = &body,
+			.counter = counter,
 		};
 
 		if (!aor) {
@@ -454,8 +477,6 @@ static void send_unsolicited_mwi_notify(struct mwi_subscription *sub,
 
 		ao2_callback(contacts, OBJ_NODATA, send_unsolicited_mwi_notify_to_contact, &mwi_data);
 	}
-
-	ast_free(body_text);
 }
 
 static void send_mwi_notify(struct mwi_subscription *sub)
@@ -463,6 +484,7 @@ static void send_mwi_notify(struct mwi_subscription *sub)
 	struct ast_sip_message_accumulator counter = {
 		.old_msgs = 0,
 		.new_msgs = 0,
+		.message_account[0] = '\0',
 	};
 	struct ast_sip_body_data data = {
 		.body_type = AST_SIP_MESSAGE_ACCUMULATOR,
@@ -472,7 +494,17 @@ static void send_mwi_notify(struct mwi_subscription *sub)
 	ao2_callback(sub->stasis_subs, OBJ_NODATA, get_message_count, &counter);
 
 	if (sub->is_solicited) {
+		struct ast_sip_aor *aor = ast_sip_location_retrieve_aor(ast_sip_subscription_get_resource_name(sub->sip_sub));
+		pjsip_dialog *dlg = ast_sip_subscription_get_dialog(sub->sip_sub);
+		pjsip_sip_uri *sip_uri = ast_sip_subscription_get_sip_uri(sub->sip_sub);
+
+		if (aor && dlg && sip_uri) {
+			set_voicemail_extension(dlg->pool, sip_uri, &counter, aor->voicemail_extension);
+		}
+
+		ao2_cleanup(aor);
 		ast_sip_subscription_notify(sub->sip_sub, &data, 0);
+
 		return;
 	}
 
@@ -565,7 +597,12 @@ static int endpoint_receives_unsolicited_mwi_for_mailbox(struct ast_sip_endpoint
 
 		mwi_stasis = ao2_find(mwi_sub->stasis_subs, mailbox, OBJ_SEARCH_KEY);
 		if (mwi_stasis) {
-			ret = 1;
+			if (endpoint->subscription.mwi.subscribe_replaces_unsolicited) {
+				unsubscribe_stasis(mwi_stasis, NULL, 0);
+				ao2_unlink(mwi_sub->stasis_subs, mwi_stasis);
+			} else {
+				ret = 1;
+			}
 			ao2_cleanup(mwi_stasis);
 		}
 	}
@@ -771,6 +808,7 @@ static void *mwi_get_notify_data(struct ast_sip_subscription *sub)
 	struct ast_sip_message_accumulator *counter;
 	struct mwi_subscription *mwi_sub;
 	struct ast_datastore *mwi_datastore;
+	struct ast_sip_aor *aor;
 
 	mwi_datastore = ast_sip_subscription_get_datastore(sub, MWI_DATASTORE);
 	if (!mwi_datastore) {
@@ -784,6 +822,16 @@ static void *mwi_get_notify_data(struct ast_sip_subscription *sub)
 		return NULL;
 	}
 
+	if ((aor = ast_sip_location_retrieve_aor(ast_sip_subscription_get_resource_name(sub)))) {
+		pjsip_dialog *dlg = ast_sip_subscription_get_dialog(sub);
+		pjsip_sip_uri *sip_uri = ast_sip_subscription_get_sip_uri(sub);
+
+		if (dlg && sip_uri) {
+			set_voicemail_extension(dlg->pool, sip_uri, counter, aor->voicemail_extension);
+		}
+		ao2_ref(aor, -1);
+	}
+
 	ao2_callback(mwi_sub->stasis_subs, OBJ_NODATA, get_message_count, counter);
 	ao2_cleanup(mwi_datastore);
 	return counter;
@@ -1084,6 +1132,16 @@ static void mwi_startup_event_cb(void *data, struct stasis_subscription *sub, st
 	stasis_unsubscribe(sub);
 }
 
+static void global_loaded(const char *object_type)
+{
+	ast_free(default_voicemail_extension);
+	default_voicemail_extension = ast_sip_get_default_voicemail_extension();
+}
+
+static struct ast_sorcery_observer global_observer = {
+	.loaded = global_loaded,
+};
+
 static int reload(void)
 {
 	create_mwi_subscriptions();
@@ -1106,6 +1164,8 @@ static int load_module(void)
 
 	create_mwi_subscriptions();
 	ast_sorcery_observer_add(ast_sip_get_sorcery(), "contact", &mwi_contact_observer);
+	ast_sorcery_observer_add(ast_sip_get_sorcery(), "global", &global_observer);
+	ast_sorcery_reload_object(ast_sip_get_sorcery(), "global");
 
 	if (ast_test_flag(&ast_options, AST_OPT_FLAG_FULLY_BOOTED)) {
 		ast_sip_push_task(NULL, send_initial_notify_all, NULL);
@@ -1120,8 +1180,10 @@ static int unload_module(void)
 {
 	ao2_callback(unsolicited_mwi, OBJ_UNLINK | OBJ_NODATA | OBJ_MULTIPLE, unsubscribe, NULL);
 	ao2_ref(unsolicited_mwi, -1);
+	ast_sorcery_observer_remove(ast_sip_get_sorcery(), "global", &global_observer);
 	ast_sorcery_observer_remove(ast_sip_get_sorcery(), "contact", &mwi_contact_observer);
 	ast_sip_unregister_subscription_handler(&mwi_handler);
+	ast_free(default_voicemail_extension);
 	return 0;
 }