ARI: Don't leak implementation details

This change prevents channels used as implementation details from
leaking out to ARI. It does this by preventing creation of JSON blobs
of channel snapshots created from those channels and sanitizing JSON
blobs of bridge snapshots as they are created. This introduces a
framework for excluding information from output targeted at Stasis
applications on a consumer-by-consumer basis using channel sanitization
callbacks which could be extended to bridges or endpoints if necessary.

This prevents unhelpful error messages from being generated by
ast_json_pack.

This also corrects a bug where BridgeCreated events would not be
created.

(closes issue ASTERISK-22744)
Review: https://reviewboard.asterisk.org/r/2987/
Reported by: David M. Lee
........

Merged revisions 403069 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@403070 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 60 insertions, 27 deletions

diff --git a/main/stasis_bridges.c b/main/stasis_bridges.c
index 7d078f9d0..b92d048bc 100644
--- a/main/stasis_bridges.c
+++ b/main/stasis_bridges.c
@@ -135,9 +135,15 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 
 static struct ast_manager_event_blob *attended_transfer_to_ami(struct stasis_message *message);
 static struct ast_manager_event_blob *blind_transfer_to_ami(struct stasis_message *message);
-static struct ast_json *ast_channel_entered_bridge_to_json(struct stasis_message *msg);
-static struct ast_json *ast_channel_left_bridge_to_json(struct stasis_message *msg);
-static struct ast_json *ast_bridge_merge_message_to_json(struct stasis_message *msg);
+static struct ast_json *ast_channel_entered_bridge_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize);
+static struct ast_json *ast_channel_left_bridge_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize);
+static struct ast_json *ast_bridge_merge_message_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize);
 
 static struct stasis_cp_all *bridge_cache_all;
 
@@ -316,17 +322,25 @@ static struct ast_bridge_merge_message *bridge_merge_message_create(struct ast_b
 	return msg;
 }
 
-static struct ast_json *ast_bridge_merge_message_to_json(struct stasis_message *msg)
+static struct ast_json *ast_bridge_merge_message_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize)
 {
-	struct ast_bridge_merge_message *merge;
+	struct ast_bridge_merge_message *merge = stasis_message_data(msg);
+	RAII_VAR(struct ast_json *, json_bridge_to,
+		ast_bridge_snapshot_to_json(merge->to, sanitize), ast_json_unref);
+	RAII_VAR(struct ast_json *, json_bridge_from,
+		ast_bridge_snapshot_to_json(merge->from, sanitize), ast_json_unref);
 
-	merge = stasis_message_data(msg);
+	if (!json_bridge_to || !json_bridge_from) {
+		return NULL;
+	}
 
-        return ast_json_pack("{s: s, s: o, s: o, s: o}",
+        return ast_json_pack("{s: s, s: o, s: O, s: O}",
                 "type", "BridgeMerged",
                 "timestamp", ast_json_timeval(*stasis_message_timestamp(msg), NULL),
-                "bridge", ast_bridge_snapshot_to_json(merge->to),
-                "bridge_from", ast_bridge_snapshot_to_json(merge->from));
+                "bridge", json_bridge_to,
+                "bridge_from", json_bridge_from);
 }
 
 void ast_bridge_publish_merge(struct ast_bridge *to, struct ast_bridge *from)
@@ -443,45 +457,63 @@ static struct ast_json *simple_bridge_channel_event(
         const char *type,
         struct ast_bridge_snapshot *bridge_snapshot,
         struct ast_channel_snapshot *channel_snapshot,
-        const struct timeval *tv)
+        const struct timeval *tv,
+	const struct stasis_message_sanitizer *sanitize)
 {
-        return ast_json_pack("{s: s, s: o, s: o, s: o}",
+	RAII_VAR(struct ast_json *, json_bridge,
+		ast_bridge_snapshot_to_json(bridge_snapshot, sanitize), ast_json_unref);
+	RAII_VAR(struct ast_json *, json_channel,
+		ast_channel_snapshot_to_json(channel_snapshot, sanitize), ast_json_unref);
+
+	if (!json_bridge || !json_channel) {
+		return NULL;
+	}
+
+        return ast_json_pack("{s: s, s: o, s: O, s: O}",
                 "type", type,
                 "timestamp", ast_json_timeval(*tv, NULL),
-                "bridge", ast_bridge_snapshot_to_json(bridge_snapshot),
-                "channel", ast_channel_snapshot_to_json(channel_snapshot));
+                "bridge", json_bridge,
+                "channel", json_channel);
 }
 
-struct ast_json *ast_channel_entered_bridge_to_json(struct stasis_message *msg)
+struct ast_json *ast_channel_entered_bridge_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize)
 {
         struct ast_bridge_blob *obj = stasis_message_data(msg);
 
 	return simple_bridge_channel_event("ChannelEnteredBridge", obj->bridge,
-                obj->channel, stasis_message_timestamp(msg));
+                obj->channel, stasis_message_timestamp(msg), sanitize);
 }
 
-struct ast_json *ast_channel_left_bridge_to_json(struct stasis_message *msg)
+struct ast_json *ast_channel_left_bridge_to_json(
+	struct stasis_message *msg,
+	const struct stasis_message_sanitizer *sanitize)
 {
         struct ast_bridge_blob *obj = stasis_message_data(msg);
 
 	return simple_bridge_channel_event("ChannelLeftBridge", obj->bridge,
-                obj->channel, stasis_message_timestamp(msg));
+                obj->channel, stasis_message_timestamp(msg), sanitize);
 }
 
-typedef struct ast_json *(*json_item_serializer_cb)(void *obj);
-
-static struct ast_json *container_to_json_array(struct ao2_container *items, json_item_serializer_cb item_cb)
+static struct ast_json *container_to_json_array(struct ao2_container *items,
+	const struct stasis_message_sanitizer *sanitize)
 {
 	RAII_VAR(struct ast_json *, json_items, ast_json_array_create(), ast_json_unref);
-	void *item;
+	char *item;
 	struct ao2_iterator it;
 	if (!json_items) {
 		return NULL;
 	}
 
-	it = ao2_iterator_init(items, 0);
-	while ((item = ao2_iterator_next(&it))) {
-		if (ast_json_array_append(json_items, item_cb(item))) {
+	for (it = ao2_iterator_init(items, 0);
+		(item = ao2_iterator_next(&it)); ao2_cleanup(item)) {
+		if (sanitize && sanitize->channel_id && sanitize->channel_id(item)) {
+			continue;
+		}
+
+		if (ast_json_array_append(json_items, ast_json_string_create(item))) {
+			ao2_cleanup(item);
 			ao2_iterator_destroy(&it);
 			return NULL;
 		}
@@ -500,7 +532,9 @@ static const char *capability2str(uint32_t capabilities)
 	}
 }
 
-struct ast_json *ast_bridge_snapshot_to_json(const struct ast_bridge_snapshot *snapshot)
+struct ast_json *ast_bridge_snapshot_to_json(
+	const struct ast_bridge_snapshot *snapshot,
+	const struct stasis_message_sanitizer *sanitize)
 {
 	RAII_VAR(struct ast_json *, json_bridge, NULL, ast_json_unref);
 	struct ast_json *json_channels;
@@ -509,8 +543,7 @@ struct ast_json *ast_bridge_snapshot_to_json(const struct ast_bridge_snapshot *s
 		return NULL;
 	}
 
-	json_channels = container_to_json_array(snapshot->channels,
-		(json_item_serializer_cb)ast_json_string_create);
+	json_channels = container_to_json_array(snapshot->channels, sanitize);
 	if (!json_channels) {
 		return NULL;
 	}