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From: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
To: linux-bluetooth@vger.kernel.org
Subject: [PATCH BlueZ v2] adapter: Fix link key address type for old kernels
Date: Wed, 20 Dec 2023 12:40:42 -0500
Message-ID: <20231220174042.2335819-1-luiz.dentz@gmail.com>
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From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

On old kernels only BDADDR_BREDR is supported so this attempts to detect
that and retry.

Fixes: https://github.com/bluez/bluez/issues/686
---
 src/adapter.c | 59 ++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 44 insertions(+), 15 deletions(-)

diff --git a/src/adapter.c b/src/adapter.c
index ee70b00d249e..022390f0d95d 100644
--- a/src/adapter.c
+++ b/src/adapter.c
@@ -311,6 +311,7 @@ struct btd_adapter {
 	bool pincode_requested;		/* PIN requested during last bonding */
 	GSList *connections;		/* Connected devices */
 	GSList *devices;		/* Devices structure pointers */
+	GSList *load_keys;		/* Devices keys to be loaded */
 	GSList *connect_list;		/* Devices to connect when found */
 	struct btd_device *connect_le;	/* LE device waiting to be connected */
 	sdp_list_t *services;		/* Services associated to adapter */
@@ -4284,6 +4285,9 @@ static int set_privacy(struct btd_adapter *adapter, uint8_t privacy)
 	return -1;
 }
 
+static void load_link_keys(struct btd_adapter *adapter, bool debug_keys,
+							bool retry);
+
 static void load_link_keys_complete(uint8_t status, uint16_t length,
 					const void *param, void *user_data)
 {
@@ -4293,18 +4297,31 @@ static void load_link_keys_complete(uint8_t status, uint16_t length,
 		btd_error(adapter->dev_id,
 			"Failed to load link keys for hci%u: %s (0x%02x)",
 				adapter->dev_id, mgmt_errstr(status), status);
+
+		if (status == MGMT_STATUS_INVALID_PARAMS) {
+			load_link_keys(adapter, btd_opts.debug_keys, true);
+			/* Release keys after retry since we shall only retry
+			 * once.
+			 */
+			goto done;
+		}
+
 		return;
 	}
 
 	DBG("link keys loaded for hci%u", adapter->dev_id);
+
+done:
+	g_slist_free_full(adapter->load_keys, g_free);
+	adapter->load_keys = NULL;
 }
 
-static void load_link_keys(struct btd_adapter *adapter, GSList *keys,
-							bool debug_keys)
+static void load_link_keys(struct btd_adapter *adapter, bool debug_keys,
+							bool retry)
 {
 	struct mgmt_cp_load_link_keys *cp;
 	struct mgmt_link_key_info *key;
-	size_t key_count, cp_size;
+	size_t count, cp_size;
 	unsigned int id;
 	GSList *l;
 
@@ -4318,12 +4335,14 @@ static void load_link_keys(struct btd_adapter *adapter, GSList *keys,
 	if (!(adapter->supported_settings & MGMT_SETTING_BREDR))
 		return;
 
-	key_count = g_slist_length(keys);
+	count = g_slist_length(adapter->load_keys);
+	if (!count)
+		return;
 
-	DBG("hci%u keys %zu debug_keys %d", adapter->dev_id, key_count,
-								debug_keys);
+	DBG("hci%u keys %zu debug_keys %d retry %s", adapter->dev_id, count,
+				debug_keys, retry ? "true" : "false");
 
-	cp_size = sizeof(*cp) + (key_count * sizeof(*key));
+	cp_size = sizeof(*cp) + (count * sizeof(*key));
 
 	cp = g_try_malloc0(cp_size);
 	if (cp == NULL) {
@@ -4341,13 +4360,18 @@ static void load_link_keys(struct btd_adapter *adapter, GSList *keys,
 	 * behavior for debug keys.
 	 */
 	cp->debug_keys = debug_keys;
-	cp->key_count = htobs(key_count);
+	cp->key_count = htobs(count);
 
-	for (l = keys, key = cp->keys; l != NULL; l = g_slist_next(l), key++) {
+	for (l = adapter->load_keys, key = cp->keys; l != NULL;
+					l = g_slist_next(l), key++) {
 		struct link_key_info *info = l->data;
 
 		bacpy(&key->addr.bdaddr, &info->bdaddr);
-		key->addr.type = info->bdaddr_type;
+		/* Old kernels might only support loading with type set to
+		 * BDADDR_BREDR so on retry set that instead of using the stored
+		 * info.
+		 */
+		key->addr.type = retry ? BDADDR_BREDR : info->bdaddr_type;
 		key->type = info->type;
 		memcpy(key->val, info->key, 16);
 		key->pin_len = info->pin_len;
@@ -4359,9 +4383,12 @@ static void load_link_keys(struct btd_adapter *adapter, GSList *keys,
 
 	g_free(cp);
 
-	if (id == 0)
+	if (id == 0) {
 		btd_error(adapter->dev_id, "Failed to load link keys for hci%u",
 							adapter->dev_id);
+		g_slist_free_full(adapter->load_keys, g_free);
+		adapter->load_keys = NULL;
+	}
 }
 
 static void load_ltks_complete(uint8_t status, uint16_t length,
@@ -4873,7 +4900,6 @@ done:
 static void load_devices(struct btd_adapter *adapter)
 {
 	char dirname[PATH_MAX];
-	GSList *keys = NULL;
 	GSList *ltks = NULL;
 	GSList *irks = NULL;
 	GSList *params = NULL;
@@ -4964,7 +4990,8 @@ static void load_devices(struct btd_adapter *adapter)
 		}
 
 		if (key_info)
-			keys = g_slist_append(keys, key_info);
+			adapter->load_keys = g_slist_append(adapter->load_keys,
+								key_info);
 
 		if (ltk_info)
 			ltks = g_slist_append(ltks, ltk_info);
@@ -5013,8 +5040,7 @@ free:
 
 	closedir(dir);
 
-	load_link_keys(adapter, keys, btd_opts.debug_keys);
-	g_slist_free_full(keys, g_free);
+	load_link_keys(adapter, btd_opts.debug_keys, false);
 
 	load_ltks(adapter, ltks);
 	g_slist_free_full(ltks, g_free);
@@ -6930,6 +6956,9 @@ static void adapter_remove(struct btd_adapter *adapter)
 	g_slist_free(adapter->devices);
 	adapter->devices = NULL;
 
+	g_slist_free(adapter->load_keys);
+	adapter->load_keys = NULL;
+
 	discovery_cleanup(adapter, 0);
 
 	unload_drivers(adapter);
-- 
2.43.0