a2dp: Invalidate cache if SetConfiguration fails

If SetConfiguration fails with Unsupported Configuration it might
indicate that either the capabilities stored are incorrect or the seid
may have changed, so this attempt to invalidate the remote seps loaded
from cache when that happens so the next time there is an attempt to
discover this will force Get(All)Capabilities to be called and cause
the cache to be updated.

Fixes https://github.com/bluez/bluez/issues/178

3 files changed, 130 insertions, 78 deletions

diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
index 86bc02994..02caa83e1 100644
--- a/profiles/audio/a2dp.c
+++ b/profiles/audio/a2dp.c
@@ -127,6 +127,7 @@ struct a2dp_remote_sep {
 	struct a2dp_channel *chan;
 	char *path;
 	struct avdtp_remote_sep *sep;
+	bool from_cache;
 };
 
 struct a2dp_last_used {
@@ -773,6 +774,105 @@ done:
 	setup_unref(setup);
 }
 
+static bool match_remote_sep(const void *data, const void *user_data)
+{
+	const struct a2dp_remote_sep *sep = data;
+	const struct avdtp_remote_sep *rsep = user_data;
+
+	return sep->sep == rsep;
+}
+
+static void store_remote_sep(void *data, void *user_data)
+{
+	struct a2dp_remote_sep *sep = data;
+	GKeyFile *key_file = user_data;
+	char seid[4], value[256];
+	struct avdtp_service_capability *service = avdtp_get_codec(sep->sep);
+	struct avdtp_media_codec_capability *codec;
+	unsigned int i;
+	ssize_t offset;
+
+	if (!service)
+		return;
+
+	codec = (void *) service->data;
+
+	sprintf(seid, "%02hhx", avdtp_get_seid(sep->sep));
+
+	offset = sprintf(value, "%02hhx:%02hhx:%02hhx:",
+			avdtp_get_type(sep->sep), codec->media_codec_type,
+			avdtp_get_delay_reporting(sep->sep));
+
+	for (i = 0; i < service->length - sizeof(*codec); i++)
+		offset += sprintf(value + offset, "%02hhx", codec->data[i]);
+
+	g_key_file_set_string(key_file, "Endpoints", seid, value);
+}
+
+static void store_remote_seps(struct a2dp_channel *chan)
+{
+	struct btd_device *device = chan->device;
+	char filename[PATH_MAX];
+	char dst_addr[18];
+	GKeyFile *key_file;
+	char *data;
+	gsize length = 0;
+
+	if (queue_isempty(chan->seps))
+		return;
+
+	ba2str(device_get_address(device), dst_addr);
+
+	snprintf(filename, PATH_MAX, STORAGEDIR "/%s/cache/%s",
+			btd_adapter_get_storage_dir(device_get_adapter(device)),
+			dst_addr);
+	key_file = g_key_file_new();
+	g_key_file_load_from_file(key_file, filename, 0, NULL);
+
+	data = g_key_file_get_string(key_file, "Endpoints", "LastUsed",
+								NULL);
+
+	/* Remove current endpoints since it might have changed */
+	g_key_file_remove_group(key_file, "Endpoints", NULL);
+
+	queue_foreach(chan->seps, store_remote_sep, key_file);
+
+	if (data) {
+		g_key_file_set_string(key_file, "Endpoints", "LastUsed",
+						data);
+		g_free(data);
+	}
+
+	data = g_key_file_to_data(key_file, &length, NULL);
+	g_file_set_contents(filename, data, length, NULL);
+
+	g_free(data);
+	g_key_file_free(key_file);
+}
+
+static void invalidate_remote_cache(struct a2dp_setup *setup,
+						struct avdtp_error *err)
+{
+	if (err->category == AVDTP_ERRNO ||
+			err->err.error_code != AVDTP_UNSUPPORTED_CONFIGURATION)
+		return;
+
+	/* Attempt to unregister Remote SEP if configuration
+	 * fails with Unsupported Configuration and it was
+	 * loaded from cache.
+	 */
+	if (setup->rsep && setup->rsep->from_cache) {
+		warn("Invalidating Remote SEP from cache");
+		avdtp_unregister_remote_sep(setup->session, setup->rsep->sep);
+		/* Update cache */
+		store_remote_seps(setup->chan);
+		/* Set error to -EAGAIN so the likes of policy plugin can
+		 * reattempt to connect.
+		 */
+		avdtp_error_init(setup->err, AVDTP_ERRNO, -EAGAIN);
+	}
+}
+
 static void setconf_cfm(struct avdtp *session, struct avdtp_local_sep *sep,
 				struct avdtp_stream *stream,
 				struct avdtp_error *err, void *user_data)
@@ -794,10 +894,12 @@ static void setconf_cfm(struct avdtp *session, struct avdtp_local_sep *sep,
 		if (setup) {
 			setup_ref(setup);
 			setup->err = err;
+			invalidate_remote_cache(setup, err);
 			finalize_config(setup);
 			setup->err = NULL;
 			setup_unref(setup);
 		}
+
 		return;
 	}
 
@@ -874,14 +976,6 @@ static void getconf_cfm(struct avdtp *session, struct avdtp_local_sep *sep,
 		DBG("Source %p: Set_Configuration_Cfm", sep);
 }
 
-static bool match_remote_sep(const void *data, const void *user_data)
-{
-	const struct a2dp_remote_sep *sep = data;
-	const struct avdtp_remote_sep *rsep = user_data;
-
-	return sep->sep == rsep;
-}
-
 static void store_last_used(struct a2dp_channel *chan, uint8_t lseid,
 							uint8_t rseid)
 {
@@ -1941,7 +2035,7 @@ static void remote_sep_destroy(void *user_data)
 		remove_remote_sep(sep);
 }
 
-static void register_remote_sep(void *data, void *user_data)
+static struct a2dp_remote_sep *register_remote_sep(void *data, void *user_data)
 {
 	struct avdtp_remote_sep *rsep = data;
 	struct a2dp_channel *chan = user_data;
@@ -1949,7 +2043,7 @@ static void register_remote_sep(void *data, void *user_data)
 
 	sep = queue_find(chan->seps, match_remote_sep, rsep);
 	if (sep)
-		return;
+		return sep;
 
 	sep = new0(struct a2dp_remote_sep, 1);
 	sep->chan = chan;
@@ -1972,7 +2066,7 @@ static void register_remote_sep(void *data, void *user_data)
 		error("Could not register remote sep %s", sep->path);
 		free(sep->path);
 		free(sep);
-		return;
+		return NULL;
 	}
 
 	DBG("Found remote SEP: %s", sep->path);
@@ -1981,6 +2075,8 @@ static void register_remote_sep(void *data, void *user_data)
 
 done:
 	queue_push_tail(chan->seps, sep);
+
+	return sep;
 }
 
 static bool match_seid(const void *data, const void *user_data)
@@ -2080,7 +2176,9 @@ static void load_remote_sep(struct a2dp_channel *chan, GKeyFile *key_file,
 			continue;
 		}
 
-		register_remote_sep(rsep, chan);
+		sep = register_remote_sep(rsep, chan);
+		if (sep)
+			sep->from_cache = true;
 	}
 
 	value = g_key_file_get_string(key_file, "Endpoints", "LastUsed", NULL);
@@ -2107,6 +2205,8 @@ static void load_remote_sep(struct a2dp_channel *chan, GKeyFile *key_file,
 		return;
 	}
 
+	DBG("LastUsed: lseid %u rseid %u", lseid, rseid);
+
 	add_last_used(chan, lsep, sep);
 }
 
@@ -2710,72 +2810,9 @@ static struct queue *a2dp_select_eps(struct avdtp *session, uint8_t type,
 	return a2dp_find_eps(session, l, NULL);
 }
 
-static void store_remote_sep(void *data, void *user_data)
+static void foreach_register_remote_sep(void *data, void *user_data)
 {
-	struct a2dp_remote_sep *sep = data;
-	GKeyFile *key_file = user_data;
-	char seid[4], value[256];
-	struct avdtp_service_capability *service = avdtp_get_codec(sep->sep);
-	struct avdtp_media_codec_capability *codec;
-	unsigned int i;
-	ssize_t offset;
-
-	if (!service)
-		return;
-
-	codec = (void *) service->data;
-
-	sprintf(seid, "%02hhx", avdtp_get_seid(sep->sep));
-
-	offset = sprintf(value, "%02hhx:%02hhx:%02hhx:",
-			avdtp_get_type(sep->sep), codec->media_codec_type,
-			avdtp_get_delay_reporting(sep->sep));
-
-	for (i = 0; i < service->length - sizeof(*codec); i++)
-		offset += sprintf(value + offset, "%02hhx", codec->data[i]);
-
-	g_key_file_set_string(key_file, "Endpoints", seid, value);
-}
-
-static void store_remote_seps(struct a2dp_channel *chan)
-{
-	struct btd_device *device = chan->device;
-	char filename[PATH_MAX];
-	char dst_addr[18];
-	GKeyFile *key_file;
-	char *data;
-	gsize length = 0;
-
-	if (queue_isempty(chan->seps))
-		return;
-
-	ba2str(device_get_address(device), dst_addr);
-
-	snprintf(filename, PATH_MAX, STORAGEDIR "/%s/cache/%s",
-			btd_adapter_get_storage_dir(device_get_adapter(device)),
-			dst_addr);
-	key_file = g_key_file_new();
-	g_key_file_load_from_file(key_file, filename, 0, NULL);
-
-	data = g_key_file_get_string(key_file, "Endpoints", "LastUsed",
-								NULL);
-
-	/* Remove current endpoints since it might have changed */
-	g_key_file_remove_group(key_file, "Endpoints", NULL);
-
-	queue_foreach(chan->seps, store_remote_sep, key_file);
-
-	if (data) {
-		g_key_file_set_string(key_file, "Endpoints", "LastUsed",
-						data);
-		g_free(data);
-	}
-
-	data = g_key_file_to_data(key_file, &length, NULL);
-	g_file_set_contents(filename, data, length, NULL);
-
-	g_free(data);
-	g_key_file_free(key_file);
+	register_remote_sep(data, user_data);
 }
 
 static void discover_cb(struct avdtp *session, GSList *seps,
@@ -2791,7 +2828,7 @@ static void discover_cb(struct avdtp *session, GSList *seps,
 		setup->err = err;
 
 	if (!err) {
-		g_slist_foreach(seps, register_remote_sep, setup->chan);
+		g_slist_foreach(seps, foreach_register_remote_sep, setup->chan);
 
 		/* Only store version has been initialized as features like
 		 * Delay Reporting may not be queried if the version in
diff --git a/profiles/audio/avdtp.c b/profiles/audio/avdtp.c
index 5d13104c1..946231b71 100644
--- a/profiles/audio/avdtp.c
+++ b/profiles/audio/avdtp.c
@@ -3364,6 +3364,19 @@ struct avdtp_remote_sep *avdtp_register_remote_sep(struct avdtp *session,
 	return sep;
 }
 
+int avdtp_unregister_remote_sep(struct avdtp *session,
+						struct avdtp_remote_sep *rsep)
+{
+	if (!session || !rsep)
+		return -EINVAL;
+
+	session->seps = g_slist_remove(session->seps, rsep);
+
+	sep_free(rsep);
+
+	return 0;
+}
+
 void avdtp_remote_sep_set_destroy(struct avdtp_remote_sep *sep, void *user_data,
 					avdtp_remote_sep_destroy_t destroy)
 {
diff --git a/profiles/audio/avdtp.h b/profiles/audio/avdtp.h
index b29d0621a..b02534cd5 100644
--- a/profiles/audio/avdtp.h
+++ b/profiles/audio/avdtp.h
@@ -215,6 +215,8 @@ struct avdtp_remote_sep *avdtp_register_remote_sep(struct avdtp *session,
 							uint8_t type,
 							GSList *caps,
 							bool delay_reporting);
+int avdtp_unregister_remote_sep(struct avdtp *session,
+						struct avdtp_remote_sep *rsep);
 
 typedef void (*avdtp_remote_sep_destroy_t)(void *user_data);