Bluetooth: Mesh: Prevent duplicate cdb appkeys

Fixes issue where it is possible to store the same appkey multiple times in CDB implementation. Signed-off-by: Anders Storrø <[email protected]>
zephyrproject-rtos · Feb 29, 2024 · 25c26ff · 25c26ff
1 parent ff8c892
commit 25c26ff
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Showing 2 changed files with 22 additions and 9 deletions.
diff --git a/include/zephyr/bluetooth/mesh/cdb.h b/include/zephyr/bluetooth/mesh/cdb.h
@@ -247,9 +247,13 @@ void bt_mesh_cdb_node_foreach(bt_mesh_cdb_node_func_t func, void *user_data);
  *
  *  Allocate a new subnet in the CDB.
  *
+ *  @note The provided net_idx must be unique, since multiple keys for the same index
+ *        is not supported.
+ *
  *  @param net_idx NetIdx of the subnet.
  *
- *  @return The new subnet or NULL if it cannot be allocated.
+ *  @return The new subnet or NULL if it cannot be allocated due to
+ *          lack of resources or the subnet has been already allocated.
  */
 struct bt_mesh_cdb_subnet *bt_mesh_cdb_subnet_alloc(uint16_t net_idx);
 
@@ -328,7 +332,8 @@ int bt_mesh_cdb_subnet_key_export(const struct bt_mesh_cdb_subnet *sub, int key_
  *  @param net_idx NetIdx of NetKey that the application key is bound to.
  *  @param app_idx AppIdx of the application key.
  *
- *  @return The new application key or NULL if it cannot be allocated.
+ *  @return The new application key or NULL if it cannot be allocated due to
+ *          lack of resources or the key has been already allocated.
  */
 struct bt_mesh_cdb_app_key *bt_mesh_cdb_app_key_alloc(uint16_t net_idx,
 						      uint16_t app_idx);

diff --git a/subsys/bluetooth/mesh/cdb.c b/subsys/bluetooth/mesh/cdb.c
@@ -94,6 +94,7 @@ struct bt_mesh_cdb bt_mesh_cdb = {
 	},
 	.app_keys = {
 		[0 ... (CONFIG_BT_MESH_CDB_APP_KEY_COUNT - 1)] = {
+			.app_idx = BT_MESH_KEY_UNUSED,
 			.net_idx = BT_MESH_KEY_UNUSED,
 		}
 	},
@@ -1024,26 +1025,32 @@ int bt_mesh_cdb_node_key_export(const struct bt_mesh_cdb_node *node, uint8_t out
 	return bt_mesh_key_export(out, &node->dev_key);
 }
 
-struct bt_mesh_cdb_app_key *bt_mesh_cdb_app_key_alloc(uint16_t net_idx,
-						      uint16_t app_idx)
+struct bt_mesh_cdb_app_key *bt_mesh_cdb_app_key_alloc(uint16_t net_idx, uint16_t app_idx)
 {
 	struct bt_mesh_cdb_app_key *key;
+	struct bt_mesh_cdb_app_key *vacant_key = NULL;
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(bt_mesh_cdb.app_keys); ++i) {
 		key = &bt_mesh_cdb.app_keys[i];
 
-		if (key->net_idx != BT_MESH_KEY_UNUSED) {
+		if (key->app_idx == app_idx) {
+			return NULL;
+		}
+
+		if (key->net_idx != BT_MESH_KEY_UNUSED || vacant_key) {
 			continue;
 		}
 
-		key->net_idx = net_idx;
-		key->app_idx = app_idx;
+		vacant_key = key;
+	}
 
-		return key;
+	if (vacant_key) {
+		vacant_key->net_idx = net_idx;
+		vacant_key->app_idx = app_idx;
 	}
 
-	return NULL;
+	return vacant_key;
 }
 
 void bt_mesh_cdb_app_key_del(struct bt_mesh_cdb_app_key *key, bool store)
@@ -1055,6 +1062,7 @@ void bt_mesh_cdb_app_key_del(struct bt_mesh_cdb_app_key *key, bool store)
 	}
 
 	key->net_idx = BT_MESH_KEY_UNUSED;
+	key->app_idx = BT_MESH_KEY_UNUSED;
 	bt_mesh_key_destroy(&key->keys[0].app_key);
 	bt_mesh_key_destroy(&key->keys[1].app_key);
 	memset(key->keys, 0, sizeof(key->keys));