Stasis: Allow message types to be blocked

This introduces stasis.conf and a mechanism to prevent certain message
types from being published. Internally, this works by preventing the
chosen message types from being created which ensures that those
message types can never be published. This patch also adjusts message
publishers such that message payloads are not created if the related
message type is not available.

ASTERISK-23943 #close
Review: https://reviewboard.asterisk.org/r/3823/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@420124 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 269 insertions, 0 deletions

diff --git a/main/stasis.c b/main/stasis.c
index 594ec5e99..d8e0e5afc 100644
--- a/main/stasis.c
+++ b/main/stasis.c
@@ -41,6 +41,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$");
 #include "asterisk/stasis_channels.h"
 #include "asterisk/stasis_bridges.h"
 #include "asterisk/stasis_endpoints.h"
+#include "asterisk/config_options.h"
 
 /*** DOCUMENTATION
 	<managerEvent language="en_US" name="UserEvent">
@@ -60,6 +61,135 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$");
 			</see-also>
 		</managerEventInstance>
 	</managerEvent>
+	<configInfo name="stasis" language="en_US">
+		<configFile name="stasis.conf">
+			<configObject name="declined_message_types">
+				<synopsis>Stasis message types for which to decline creation.</synopsis>
+				<configOption name="decline">
+					<synopsis>The message type to decline.</synopsis>
+					<description>
+						<para>This configuration option defines the name of the Stasis
+						message type that Asterisk is forbidden from creating and can be
+						specified as many times as necessary to achieve the desired result.</para>
+						<enumlist>
+							<enum name="stasis_app_recording_snapshot_type" />
+							<enum name="stasis_app_playback_snapshot_type" />
+							<enum name="stasis_test_message_type" />
+							<enum name="confbridge_start_type" />
+							<enum name="confbridge_end_type" />
+							<enum name="confbridge_join_type" />
+							<enum name="confbridge_leave_type" />
+							<enum name="confbridge_start_record_type" />
+							<enum name="confbridge_stop_record_type" />
+							<enum name="confbridge_mute_type" />
+							<enum name="confbridge_unmute_type" />
+							<enum name="confbridge_talking_type" />
+							<enum name="cel_generic_type" />
+							<enum name="ast_bridge_snapshot_type" />
+							<enum name="ast_bridge_merge_message_type" />
+							<enum name="ast_channel_entered_bridge_type" />
+							<enum name="ast_channel_left_bridge_type" />
+							<enum name="ast_blind_transfer_type" />
+							<enum name="ast_attended_transfer_type" />
+							<enum name="ast_endpoint_snapshot_type" />
+							<enum name="ast_endpoint_state_type" />
+							<enum name="ast_device_state_message_type" />
+							<enum name="ast_test_suite_message_type" />
+							<enum name="ast_mwi_state_type" />
+							<enum name="ast_mwi_vm_app_type" />
+							<enum name="ast_format_register_type" />
+							<enum name="ast_format_unregister_type" />
+							<enum name="ast_manager_get_generic_type" />
+							<enum name="ast_parked_call_type" />
+							<enum name="ast_channel_snapshot_type" />
+							<enum name="ast_channel_dial_type" />
+							<enum name="ast_channel_varset_type" />
+							<enum name="ast_channel_hangup_request_type" />
+							<enum name="ast_channel_dtmf_begin_type" />
+							<enum name="ast_channel_dtmf_end_type" />
+							<enum name="ast_channel_hold_type" />
+							<enum name="ast_channel_unhold_type" />
+							<enum name="ast_channel_chanspy_start_type" />
+							<enum name="ast_channel_chanspy_stop_type" />
+							<enum name="ast_channel_fax_type" />
+							<enum name="ast_channel_hangup_handler_type" />
+							<enum name="ast_channel_moh_start_type" />
+							<enum name="ast_channel_moh_stop_type" />
+							<enum name="ast_channel_monitor_start_type" />
+							<enum name="ast_channel_monitor_stop_type" />
+							<enum name="ast_channel_agent_login_type" />
+							<enum name="ast_channel_agent_logoff_type" />
+							<enum name="ast_channel_talking_start" />
+							<enum name="ast_channel_talking_stop" />
+							<enum name="ast_security_event_type" />
+							<enum name="ast_named_acl_change_type" />
+							<enum name="ast_local_bridge_type" />
+							<enum name="ast_local_optimization_begin_type" />
+							<enum name="ast_local_optimization_end_type" />
+							<enum name="stasis_subscription_change_type" />
+							<enum name="ast_multi_user_event_type" />
+							<enum name="stasis_cache_clear_type" />
+							<enum name="stasis_cache_update_type" />
+							<enum name="ast_network_change_type" />
+							<enum name="ast_system_registry_type" />
+							<enum name="ast_cc_available_type" />
+							<enum name="ast_cc_offertimerstart_type" />
+							<enum name="ast_cc_requested_type" />
+							<enum name="ast_cc_requestacknowledged_type" />
+							<enum name="ast_cc_callerstopmonitoring_type" />
+							<enum name="ast_cc_callerstartmonitoring_type" />
+							<enum name="ast_cc_callerrecalling_type" />
+							<enum name="ast_cc_recallcomplete_type" />
+							<enum name="ast_cc_failure_type" />
+							<enum name="ast_cc_monitorfailed_type" />
+							<enum name="ast_presence_state_message_type" />
+							<enum name="ast_rtp_rtcp_sent_type" />
+							<enum name="ast_rtp_rtcp_received_type" />
+							<enum name="ast_call_pickup_type" />
+							<enum name="aoc_s_type" />
+							<enum name="aoc_d_type" />
+							<enum name="aoc_e_type" />
+							<enum name="dahdichannel_type" />
+							<enum name="mcid_type" />
+							<enum name="session_timeout_type" />
+							<enum name="cdr_read_message_type" />
+							<enum name="cdr_write_message_type" />
+							<enum name="cdr_prop_write_message_type" />
+							<enum name="corosync_ping_message_type" />
+							<enum name="agi_exec_start_type" />
+							<enum name="agi_exec_end_type" />
+							<enum name="agi_async_start_type" />
+							<enum name="agi_async_exec_type" />
+							<enum name="agi_async_end_type" />
+							<enum name="queue_caller_join_type" />
+							<enum name="queue_caller_leave_type" />
+							<enum name="queue_caller_abandon_type" />
+							<enum name="queue_member_status_type" />
+							<enum name="queue_member_added_type" />
+							<enum name="queue_member_removed_type" />
+							<enum name="queue_member_pause_type" />
+							<enum name="queue_member_penalty_type" />
+							<enum name="queue_member_ringinuse_type" />
+							<enum name="queue_agent_called_type" />
+							<enum name="queue_agent_connect_type" />
+							<enum name="queue_agent_complete_type" />
+							<enum name="queue_agent_dump_type" />
+							<enum name="queue_agent_ringnoanswer_type" />
+							<enum name="meetme_join_type" />
+							<enum name="meetme_leave_type" />
+							<enum name="meetme_end_type" />
+							<enum name="meetme_mute_type" />
+							<enum name="meetme_talking_type" />
+							<enum name="meetme_talk_request_type" />
+							<enum name="appcdr_message_type" />
+							<enum name="forkcdr_message_type" />
+							<enum name="cdr_sync_message_type" />
+						</enumlist>
+					</description>
+				</configOption>
+			</configObject>
+		</configFile>
+	</configInfo>
 ***/
 
 /*!
@@ -801,6 +931,10 @@ static void send_subscription_subscribe(struct stasis_topic *topic, struct stasi
 	/* This assumes that we have already unsubscribed */
 	ast_assert(stasis_subscription_is_subscribed(sub));
 
+	if (!stasis_subscription_change_type()) {
+		return;
+	}
+
 	change = subscription_change_alloc(topic, sub->uniqueid, "Subscribe");
 	if (!change) {
 		return;
@@ -826,6 +960,10 @@ static void send_subscription_unsubscribe(struct stasis_topic *topic,
 	/* This assumes that we have already unsubscribed */
 	ast_assert(!stasis_subscription_is_subscribed(sub));
 
+	if (!stasis_subscription_change_type()) {
+		return;
+	}
+
 	change = subscription_change_alloc(topic, sub->uniqueid, "Unsubscribe");
 	if (!change) {
 		return;
@@ -1066,6 +1204,10 @@ void ast_multi_object_blob_single_channel_publish(struct ast_channel *chan,
 	RAII_VAR(struct ast_channel_snapshot *, channel_snapshot, NULL, ao2_cleanup);
 	RAII_VAR(struct ast_multi_object_blob *, multi, NULL, ao2_cleanup);
 
+	if (!type) {
+		return;
+	}
+
 	multi = ast_multi_object_blob_create(blob);
 	if (!multi) {
 		return;
@@ -1215,6 +1357,113 @@ static struct ast_manager_event_blob *multi_user_event_to_ami(
 		ast_str_buffer(body));
 }
 
+/*! \brief A structure to hold global configuration-related options */
+struct stasis_declined_config {
+	/*! The list of message types to decline */
+	struct ao2_container *declined;
+};
+
+
+struct stasis_config {
+	struct stasis_declined_config *declined_message_types;
+};
+
+/*! \brief An aco_type structure to link the "declined_message_types" category to the stasis_declined_config type */
+static struct aco_type declined_option = {
+	.type = ACO_GLOBAL,
+	.name = "declined_message_types",
+	.item_offset = offsetof(struct stasis_config, declined_message_types),
+	.category_match = ACO_WHITELIST,
+	.category = "^declined_message_types$",
+};
+
+struct aco_type *declined_options[] = ACO_TYPES(&declined_option);
+
+struct aco_file stasis_conf = {
+        .filename = "stasis.conf",
+	.types = ACO_TYPES(&declined_option),
+};
+
+/*! \brief A global object container that will contain the stasis_config that gets swapped out on reloads */
+static AO2_GLOBAL_OBJ_STATIC(globals);
+
+static void *stasis_config_alloc(void);
+
+/*! \brief Register information about the configs being processed by this module */
+CONFIG_INFO_CORE("stasis", cfg_info, globals, stasis_config_alloc,
+        .files = ACO_FILES(&stasis_conf),
+);
+
+static void stasis_declined_config_destructor(void *obj)
+{
+	struct stasis_declined_config *declined = obj;
+	ao2_cleanup(declined->declined);
+}
+
+static void stasis_config_destructor(void *obj)
+{
+	struct stasis_config *cfg = obj;
+	ao2_cleanup(cfg->declined_message_types);
+}
+
+static void *stasis_config_alloc(void)
+{
+	struct stasis_config *cfg;
+
+	if (!(cfg = ao2_alloc(sizeof(*cfg), stasis_config_destructor))) {
+		return NULL;
+	}
+
+	/* Allocate/initialize memory */
+	cfg->declined_message_types = ao2_alloc(sizeof(*cfg->declined_message_types), stasis_declined_config_destructor);
+	if (!cfg->declined_message_types) {
+		goto error;
+	}
+
+	cfg->declined_message_types->declined = ast_str_container_alloc(13);
+	if (!cfg->declined_message_types->declined) {
+		goto error;
+	}
+
+	return cfg;
+error:
+	ao2_ref(cfg, -1);
+	return NULL;
+}
+
+int stasis_message_type_declined(const char *name)
+{
+	RAII_VAR(struct stasis_config *, cfg, ao2_global_obj_ref(globals), ao2_cleanup);
+	char *name_in_declined;
+	int res;
+
+	if (!cfg || !cfg->declined_message_types) {
+		return 0;
+	}
+
+	name_in_declined = ao2_find(cfg->declined_message_types->declined, name, OBJ_SEARCH_KEY);
+	res = name_in_declined ? 1 : 0;
+	ao2_cleanup(name_in_declined);
+	if (res) {
+		ast_log(LOG_NOTICE, "Declining to allocate Stasis message type '%s' due to configuration\n", name);
+	}
+	return res;
+}
+
+static int declined_handler(const struct aco_option *opt, struct ast_variable *var, void *obj)
+{
+	struct stasis_declined_config *declined = obj;
+
+	if (ast_strlen_zero(var->value)) {
+		return 0;
+	}
+
+	if (ast_str_container_add(declined->declined, var->value)) {
+		return -1;
+	}
+
+	return 0;
+}
 
 /*!
  * @{ \brief Define multi user event message type(s).
@@ -1232,6 +1481,8 @@ static void stasis_cleanup(void)
 {
 	STASIS_MESSAGE_TYPE_CLEANUP(stasis_subscription_change_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_multi_user_event_type);
+	aco_info_destroy(&cfg_info);
+	ao2_global_obj_release(globals);
 }
 
 int stasis_init(void)
@@ -1241,6 +1492,24 @@ int stasis_init(void)
 	/* Be sure the types are cleaned up after the message bus */
 	ast_register_cleanup(stasis_cleanup);
 
+	if (aco_info_init(&cfg_info)) {
+		return -1;
+	}
+
+	aco_option_register_custom(&cfg_info, "decline", ACO_EXACT, declined_options, "", declined_handler, 0);
+
+	if (aco_process_config(&cfg_info, 0) == ACO_PROCESS_ERROR) {
+		RAII_VAR(struct stasis_config *, stasis_cfg, stasis_config_alloc(), ao2_cleanup);
+
+		if (aco_set_defaults(&declined_option, "declined_message_types", stasis_cfg->declined_message_types)) {
+			ast_log(LOG_ERROR, "Failed to load stasis.conf and failed to initialize defaults.\n");
+			return -1;
+		}
+
+		ast_log(LOG_NOTICE, "Could not load stasis config; using defaults\n");
+		ao2_global_obj_replace_unref(globals, stasis_cfg);
+	}
+
 	cache_init = stasis_cache_init();
 	if (cache_init != 0) {
 		return -1;