gatt: Add support for storing Service Changed CCC value
This adds support for storing CCC value of Service Changed
characteristic. Once bluetoothd is restart stored values are read
and any device subscribed to indications will receive Service Changed
indication with 0x00010-0xffff value. This is to invalidate any
non-core services since there is no way to verify if applications
will register their services in same order (or at all).
This fix accessing invalid handles by stacks that rely only on Service
Changed indication for rediscovery ie. Apple iOS.
diff --git a/doc/settings-storage.txt b/doc/settings-storage.txt
index 160bbb2..90357f7 100644
--- a/doc/settings-storage.txt
+++ b/doc/settings-storage.txt
@@ -302,3 +302,11 @@
Counter Integer Signing counter
Authenticated Boolean True if the key is authenticated
+
+[ServiceChanged]
+
+ This section holds information related to Service Changed characteristic
+ of GATT core service.
+
+ CCC_LE Integer CCC value for LE transport
+ CCC_BR/EDR Integer CCC value for BR/EDR transport
diff --git a/src/adapter.c b/src/adapter.c
index daccfdc..f91b041 100644
--- a/src/adapter.c
+++ b/src/adapter.c
@@ -8018,6 +8018,9 @@
clear_blocked(adapter);
load_devices(adapter);
+ /* restore Service Changed CCC value for bonded devices */
+ btd_gatt_database_restore_svc_chng_ccc(adapter->database);
+
/* retrieve the active connections: address the scenario where
* the are active connections before the daemon've started */
if (adapter->current_settings & MGMT_SETTING_POWERED)
diff --git a/src/device.c b/src/device.c
index ce515be..f693b70 100644
--- a/src/device.c
+++ b/src/device.c
@@ -5250,6 +5250,10 @@
{
return &device->bdaddr;
}
+uint8_t device_get_le_address_type(struct btd_device *device)
+{
+ return device->bdaddr_type;
+}
const char *device_get_path(const struct btd_device *device)
{
@@ -5347,6 +5351,80 @@
DEVICE_INTERFACE, "LegacyPairing");
}
+void device_store_svc_chng_ccc(struct btd_device *device, uint8_t bdaddr_type,
+ uint16_t value)
+{
+ char filename[PATH_MAX];
+ char device_addr[18];
+ GKeyFile *key_file;
+ uint16_t old_value;
+ gsize length = 0;
+ char *str;
+
+ ba2str(&device->bdaddr, device_addr);
+ snprintf(filename, PATH_MAX, STORAGEDIR "/%s/%s/info",
+ btd_adapter_get_storage_dir(device->adapter),
+ device_addr);
+
+ key_file = g_key_file_new();
+ g_key_file_load_from_file(key_file, filename, 0, NULL);
+
+ /* for bonded devices this is done on every connection so limit writes
+ * to storage if no change needed
+ */
+ if (bdaddr_type == BDADDR_BREDR) {
+ old_value = g_key_file_get_integer(key_file, "ServiceChanged",
+ "CCC_BR/EDR", NULL);
+ if (old_value == value)
+ goto done;
+
+ g_key_file_set_integer(key_file, "ServiceChanged", "CCC_BR/EDR",
+ value);
+ } else {
+ old_value = g_key_file_get_integer(key_file, "ServiceChanged",
+ "CCC_LE", NULL);
+ if (old_value == value)
+ goto done;
+
+ g_key_file_set_integer(key_file, "ServiceChanged", "CCC_LE",
+ value);
+ }
+
+ create_file(filename, S_IRUSR | S_IWUSR);
+
+ str = g_key_file_to_data(key_file, &length, NULL);
+ g_file_set_contents(filename, str, length, NULL);
+ g_free(str);
+
+done:
+ g_key_file_free(key_file);
+}
+void device_load_svc_chng_ccc(struct btd_device *device, uint16_t *ccc_le,
+ uint16_t *ccc_bredr)
+{
+ char filename[PATH_MAX];
+ char device_addr[18];
+ GKeyFile *key_file;
+
+ ba2str(&device->bdaddr, device_addr);
+ snprintf(filename, PATH_MAX, STORAGEDIR "/%s/%s/info",
+ btd_adapter_get_storage_dir(device->adapter),
+ device_addr);
+
+ key_file = g_key_file_new();
+ g_key_file_load_from_file(key_file, filename, 0, NULL);
+
+ if (ccc_le)
+ *ccc_le = g_key_file_get_integer(key_file, "ServiceChanged",
+ "CCC_LE", NULL);
+
+ if (ccc_bredr)
+ *ccc_bredr = g_key_file_get_integer(key_file, "ServiceChanged",
+ "CCC_BR/EDR", NULL);
+
+ g_key_file_free(key_file);
+}
+
void device_set_rssi_with_delta(struct btd_device *device, int8_t rssi,
int8_t delta_threshold)
{
diff --git a/src/device.h b/src/device.h
index 306c813..b90f927 100644
--- a/src/device.h
+++ b/src/device.h
@@ -87,6 +87,7 @@
void device_remove_profile(gpointer a, gpointer b);
struct btd_adapter *device_get_adapter(struct btd_device *device);
const bdaddr_t *device_get_address(struct btd_device *device);
+uint8_t device_get_le_address_type(struct btd_device *device);
const char *device_get_path(const struct btd_device *device);
gboolean device_is_temporary(struct btd_device *device);
bool device_is_connectable(struct btd_device *device);
@@ -132,6 +133,11 @@
bool device_is_disconnecting(struct btd_device *device);
void device_set_ltk_enc_size(struct btd_device *device, uint8_t enc_size);
+void device_store_svc_chng_ccc(struct btd_device *device, uint8_t bdaddr_type,
+ uint16_t value);
+void device_load_svc_chng_ccc(struct btd_device *device, uint16_t *ccc_le,
+ uint16_t *ccc_bredr);
+
typedef void (*disconnect_watch) (struct btd_device *device, gboolean removal,
void *user_data);
diff --git a/src/gatt-database.c b/src/gatt-database.c
index 5e2390b..1cdc72e 100644
--- a/src/gatt-database.c
+++ b/src/gatt-database.c
@@ -264,7 +264,7 @@
}
static struct device_state *device_state_create(struct btd_gatt_database *db,
- bdaddr_t *bdaddr,
+ const bdaddr_t *bdaddr,
uint8_t bdaddr_type)
{
struct device_state *dev_state;
@@ -324,8 +324,19 @@
if (!device)
goto remove;
- if (device_is_bonded(device, state->bdaddr_type))
+ if (device_is_bonded(device, state->bdaddr_type)) {
+ struct ccc_state *ccc;
+ uint16_t handle;
+
+ handle = gatt_db_attribute_get_handle(state->db->svc_chngd_ccc);
+
+ ccc = find_ccc_state(state, handle);
+ if (ccc)
+ device_store_svc_chng_ccc(device, state->bdaddr_type,
+ ccc->value[0]);
+
return;
+ }
remove:
/* Remove device state if device no longer exists or is not paired */
@@ -1076,6 +1087,7 @@
{
uint16_t start, end, old_start, old_end;
+ /* Cache this only for Service Changed */
if (notify->conf != service_changed_conf)
return;
@@ -3275,3 +3287,72 @@
free(state->pending);
state->pending = NULL;
}
+
+static void restore_ccc(struct btd_gatt_database *database,
+ const bdaddr_t *addr, uint8_t addr_type, uint16_t value)
+{
+ struct device_state *dev_state;
+ struct ccc_state *ccc;
+
+ dev_state = device_state_create(database, addr, addr_type);
+ queue_push_tail(database->device_states, dev_state);
+
+ ccc = new0(struct ccc_state, 1);
+ ccc->handle = gatt_db_attribute_get_handle(database->svc_chngd_ccc);
+ memcpy(ccc->value, &value, sizeof(ccc->value));
+ queue_push_tail(dev_state->ccc_states, ccc);
+}
+
+static void restore_state(struct btd_device *device, void *data)
+{
+ struct btd_gatt_database *database = data;
+ uint16_t ccc_le, ccc_bredr;
+
+ device_load_svc_chng_ccc(device, &ccc_le, &ccc_bredr);
+
+ if (ccc_le) {
+ restore_ccc(database, device_get_address(device),
+ device_get_le_address_type(device), ccc_le);
+
+ DBG("%s LE", device_get_path(device));
+ }
+
+ if (ccc_bredr) {
+ restore_ccc(database, device_get_address(device),
+ BDADDR_BREDR, ccc_bredr);
+
+ DBG("%s BR/EDR", device_get_path(device));
+ }
+}
+
+void btd_gatt_database_restore_svc_chng_ccc(struct btd_gatt_database *database)
+{
+ uint8_t value[4];
+ uint16_t handle, ccc_handle;
+
+ handle = gatt_db_attribute_get_handle(database->svc_chngd);
+ ccc_handle = gatt_db_attribute_get_handle(database->svc_chngd_ccc);
+
+ if (!handle || !ccc_handle) {
+ error("Failed to obtain handles for \"Service Changed\""
+ " characteristic");
+ return;
+ }
+
+ /* restore states for bonded device that registered for Service Changed
+ * indication
+ */
+ btd_adapter_for_each_device(database->adapter, restore_state, database);
+
+ /* This needs to be updated (probably to 0x0001) if we ever change
+ * core services
+ *
+ * TODO we could also store this info (along with CCC value) and be able
+ * to send 0x0001-0xffff only once per device.
+ */
+ put_le16(0x000a, value);
+ put_le16(0xffff, value + 2);
+
+ send_notification_to_devices(database, handle, value, sizeof(value),
+ ccc_handle, service_changed_conf, NULL);
+}
diff --git a/src/gatt-database.h b/src/gatt-database.h
index 0da33f6..a6c3139 100644
--- a/src/gatt-database.h
+++ b/src/gatt-database.h
@@ -25,3 +25,5 @@
struct gatt_db *btd_gatt_database_get_db(struct btd_gatt_database *database);
void btd_gatt_database_att_connected(struct btd_gatt_database *database,
struct bt_att *att);
+
+void btd_gatt_database_restore_svc_chng_ccc(struct btd_gatt_database *database);
