Bluetooth: Implement the Add Advertising command

This patch adds the most basic implementation for the
"Add Advertisement" command. All state updates between the
various HCI settings (POWERED, ADVERTISING, ADVERTISING_INSTANCE,
and LE_ENABLED) has been implemented. The command currently
supports only setting the advertising data fields, with no flags
and no scan response data.
Signed-off-by: NArman Uguray <armansito@chromium.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/bluetooth/mgmt.c

@@ -100,6 +100,7 @@ static const u16 mgmt_commands[] = {
 	MGMT_OP_READ_LOCAL_OOB_EXT_DATA,
 	MGMT_OP_READ_EXT_INDEX_LIST,
 	MGMT_OP_READ_ADV_FEATURES,
+	MGMT_OP_ADD_ADVERTISING,
 };
 
 static const u16 mgmt_events[] = {
@@ -135,6 +136,8 @@ static const u16 mgmt_events[] = {
 	MGMT_EV_EXT_INDEX_ADDED,
 	MGMT_EV_EXT_INDEX_REMOVED,
 	MGMT_EV_LOCAL_OOB_DATA_UPDATED,
+	MGMT_EV_ADVERTISING_ADDED,
+	MGMT_EV_ADVERTISING_REMOVED,
 };
 
 #define CACHE_TIMEOUT	msecs_to_jiffies(2 * 1000)
@@ -864,7 +867,7 @@ static u8 get_adv_discov_flags(struct hci_dev *hdev)
 	return 0;
 }
 
-static u8 create_adv_data(struct hci_dev *hdev, u8 *ptr)
+static u8 create_default_adv_data(struct hci_dev *hdev, u8 *ptr)
 {
 	u8 ad_len = 0, flags = 0;
 
@@ -896,7 +899,18 @@ static u8 create_adv_data(struct hci_dev *hdev, u8 *ptr)
 	return ad_len;
 }
 
-static void update_adv_data(struct hci_request *req)
+static u8 create_instance_adv_data(struct hci_dev *hdev, u8 *ptr)
+{
+	/* TODO: Set the appropriate entries based on advertising instance flags
+	 * here once flags other than 0 are supported.
+	 */
+	memcpy(ptr, hdev->adv_instance.adv_data,
+	       hdev->adv_instance.adv_data_len);
+
+	return hdev->adv_instance.adv_data_len;
+}
+
+static void update_adv_data_for_instance(struct hci_request *req, u8 instance)
 {
 	struct hci_dev *hdev = req->hdev;
 	struct hci_cp_le_set_adv_data cp;
@@ -907,8 +921,12 @@ static void update_adv_data(struct hci_request *req)
 
 	memset(&cp, 0, sizeof(cp));
 
-	len = create_adv_data(hdev, cp.data);
+	if (instance)
+		len = create_instance_adv_data(hdev, cp.data);
+	else
+		len = create_default_adv_data(hdev, cp.data);
 
+	/* There's nothing to do if the data hasn't changed */
 	if (hdev->adv_data_len == len &&
 	    memcmp(cp.data, hdev->adv_data, len) == 0)
 		return;
@@ -921,6 +939,25 @@ static void update_adv_data(struct hci_request *req)
 	hci_req_add(req, HCI_OP_LE_SET_ADV_DATA, sizeof(cp), &cp);
 }
 
+static void update_adv_data(struct hci_request *req)
+{
+	struct hci_dev *hdev = req->hdev;
+	u8 instance;
+
+	/* The "Set Advertising" setting supersedes the "Add Advertising"
+	 * setting. Here we set the advertising data based on which
+	 * setting was set. When neither apply, default to the global settings,
+	 * represented by instance "0".
+	 */
+	if (hci_dev_test_flag(hdev, HCI_ADVERTISING_INSTANCE) &&
+	    !hci_dev_test_flag(hdev, HCI_ADVERTISING))
+		instance = 0x01;
+	else
+		instance = 0x00;
+
+	update_adv_data_for_instance(req, instance);
+}
+
 int mgmt_update_adv_data(struct hci_dev *hdev)
 {
 	struct hci_request req;
@@ -4374,10 +4411,17 @@ static int set_device_id(struct sock *sk, struct hci_dev *hdev, void *data,
 	return err;
 }
 
+static void enable_advertising_instance(struct hci_dev *hdev, u8 status,
+					u16 opcode)
+{
+	BT_DBG("status %d", status);
+}
+
 static void set_advertising_complete(struct hci_dev *hdev, u8 status,
 				     u16 opcode)
 {
 	struct cmd_lookup match = { NULL, hdev };
+	struct hci_request req;
 
 	hci_dev_lock(hdev);
 
@@ -4402,6 +4446,21 @@ static void set_advertising_complete(struct hci_dev *hdev, u8 status,
 	if (match.sk)
 		sock_put(match.sk);
 
+	/* If "Set Advertising" was just disabled and instance advertising was
+	 * set up earlier, then enable the advertising instance.
+	 */
+	if (hci_dev_test_flag(hdev, HCI_ADVERTISING) ||
+	    !hci_dev_test_flag(hdev, HCI_ADVERTISING_INSTANCE))
+		goto unlock;
+
+	hci_req_init(&req, hdev);
+
+	update_adv_data(&req);
+	enable_advertising(&req);
+
+	if (hci_req_run(&req, enable_advertising_instance) < 0)
+		BT_ERR("Failed to re-configure advertising");
+
 unlock:
 	hci_dev_unlock(hdev);
 }
@@ -4484,10 +4543,13 @@ static int set_advertising(struct sock *sk, struct hci_dev *hdev, void *data,
 	else
 		hci_dev_clear_flag(hdev, HCI_ADVERTISING_CONNECTABLE);
 
-	if (val)
+	if (val) {
+		/* Switch to instance "0" for the Set Advertising setting. */
+		update_adv_data_for_instance(&req, 0);
 		enable_advertising(&req);
-	else
+	} else {
 		disable_advertising(&req);
+	}
 
 	err = hci_req_run(&req, set_advertising_complete);
 	if (err < 0)
@@ -6299,12 +6361,21 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
 	struct mgmt_rp_read_adv_features *rp;
 	size_t rp_len;
 	int err;
+	bool instance;
 
 	BT_DBG("%s", hdev->name);
 
 	hci_dev_lock(hdev);
 
 	rp_len = sizeof(*rp);
+
+	/* Currently only one instance is supported, so just add 1 to the
+	 * response length.
+	 */
+	instance = hci_dev_test_flag(hdev, HCI_ADVERTISING_INSTANCE);
+	if (instance)
+		rp_len++;
+
 	rp = kmalloc(rp_len, GFP_ATOMIC);
 	if (!rp) {
 		hci_dev_unlock(hdev);
@@ -6314,8 +6385,17 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
 	rp->supported_flags = cpu_to_le32(0);
 	rp->max_adv_data_len = HCI_MAX_AD_LENGTH;
 	rp->max_scan_rsp_len = HCI_MAX_AD_LENGTH;
-	rp->max_instances = 0;
-	rp->num_instances = 0;
+	rp->max_instances = 1;
+
+	/* Currently only one instance is supported, so simply return the
+	 * current instance number.
+	 */
+	if (instance) {
+		rp->num_instances = 1;
+		rp->instance[0] = 1;
+	} else {
+		rp->num_instances = 0;
+	}
 
 	hci_dev_unlock(hdev);
 
@@ -6327,6 +6407,179 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
 	return err;
 }
 
+static bool adv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *adv_data,
+			      u8 adv_data_len)
+{
+	u8 max_adv_len = HCI_MAX_AD_LENGTH;
+	int i, cur_len;
+
+	/* TODO: Correctly reduce adv_len based on adv_flags. */
+
+	if (adv_data_len > max_adv_len)
+		return false;
+
+	/* Make sure that adv_data is correctly formatted. */
+	for (i = 0, cur_len = 0; i < adv_data_len; i += (cur_len + 1)) {
+		cur_len = adv_data[i];
+
+		/* If the current field length would exceed the total data
+		 * length, then it's invalid.
+		 */
+		if (i + cur_len >= adv_data_len)
+			return false;
+	}
+
+	return true;
+}
+
+static void advertising_added(struct sock *sk, struct hci_dev *hdev,
+			      u8 instance)
+{
+	struct mgmt_ev_advertising_added ev;
+
+	ev.instance = instance;
+
+	mgmt_event(MGMT_EV_ADVERTISING_ADDED, hdev, &ev, sizeof(ev), sk);
+}
+
+static void advertising_removed(struct sock *sk, struct hci_dev *hdev,
+				u8 instance)
+{
+	struct mgmt_ev_advertising_removed ev;
+
+	ev.instance = instance;
+
+	mgmt_event(MGMT_EV_ADVERTISING_REMOVED, hdev, &ev, sizeof(ev), sk);
+}
+
+static void add_advertising_complete(struct hci_dev *hdev, u8 status,
+				     u16 opcode)
+{
+	struct mgmt_pending_cmd *cmd;
+	struct mgmt_rp_add_advertising rp;
+
+	BT_DBG("status %d", status);
+
+	hci_dev_lock(hdev);
+
+	cmd = pending_find(MGMT_OP_ADD_ADVERTISING, hdev);
+
+	if (status) {
+		hci_dev_clear_flag(hdev, HCI_ADVERTISING_INSTANCE);
+		memset(&hdev->adv_instance, 0, sizeof(hdev->adv_instance));
+		advertising_removed(cmd ? cmd->sk : NULL, hdev, 1);
+	}
+
+	if (!cmd)
+		goto unlock;
+
+	rp.instance = 0x01;
+
+	if (status)
+		mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode,
+				mgmt_status(status));
+	else
+		mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
+				  mgmt_status(status), &rp, sizeof(rp));
+
+	mgmt_pending_remove(cmd);
+
+unlock:
+	hci_dev_unlock(hdev);
+}
+
+static int add_advertising(struct sock *sk, struct hci_dev *hdev,
+			   void *data, u16 data_len)
+{
+	struct mgmt_cp_add_advertising *cp = data;
+	struct mgmt_rp_add_advertising rp;
+	u32 flags;
+	u8 status;
+	int err;
+	struct mgmt_pending_cmd *cmd;
+	struct hci_request req;
+
+	BT_DBG("%s", hdev->name);
+
+	status = mgmt_le_support(hdev);
+	if (status)
+		return mgmt_cmd_status(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
+				       status);
+
+	flags = __le32_to_cpu(cp->flags);
+
+	/* The current implementation only supports adding one instance and
+	 * doesn't support flags.
+	 */
+	if (cp->instance != 0x01 || flags)
+		return mgmt_cmd_status(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
+				       MGMT_STATUS_INVALID_PARAMS);
+
+	hci_dev_lock(hdev);
+
+	if (pending_find(MGMT_OP_ADD_ADVERTISING, hdev) ||
+	    pending_find(MGMT_OP_SET_LE, hdev)) {
+		err = mgmt_cmd_status(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
+				      MGMT_STATUS_BUSY);
+		goto unlock;
+	}
+
+	if (!adv_data_is_valid(hdev, flags, cp->data, cp->adv_data_len)) {
+		err = mgmt_cmd_status(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
+				      MGMT_STATUS_INVALID_PARAMS);
+		goto unlock;
+	}
+
+	hdev->adv_instance.flags = flags;
+	hdev->adv_instance.adv_data_len = cp->adv_data_len;
+	hdev->adv_instance.scan_rsp_len = cp->scan_rsp_len;
+
+	if (cp->adv_data_len)
+		memcpy(hdev->adv_instance.adv_data, cp->data, cp->adv_data_len);
+
+	if (cp->scan_rsp_len)
+		memcpy(hdev->adv_instance.scan_rsp_data,
+		       cp->data + cp->adv_data_len, cp->scan_rsp_len);
+
+	if (!hci_dev_test_and_set_flag(hdev, HCI_ADVERTISING_INSTANCE))
+		advertising_added(sk, hdev, 1);
+
+	/* If the HCI_ADVERTISING flag is set or the device isn't powered then
+	 * we have no HCI communication to make. Simply return.
+	 */
+	if (!hdev_is_powered(hdev) ||
+	    hci_dev_test_flag(hdev, HCI_ADVERTISING)) {
+		rp.instance = 0x01;
+		err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
+					MGMT_STATUS_SUCCESS, &rp, sizeof(rp));
+		goto unlock;
+	}
+
+	/* We're good to go, update advertising data, parameters, and start
+	 * advertising.
+	 */
+	cmd = mgmt_pending_add(sk, MGMT_OP_ADD_ADVERTISING, hdev, data,
+			       data_len);
+	if (!cmd) {
+		err = -ENOMEM;
+		goto unlock;
+	}
+
+	hci_req_init(&req, hdev);
+
+	update_adv_data(&req);
+	enable_advertising(&req);
+
+	err = hci_req_run(&req, add_advertising_complete);
+	if (err < 0)
+		mgmt_pending_remove(cmd);
+
+unlock:
+	hci_dev_unlock(hdev);
+
+	return err;
+}
+
 static const struct hci_mgmt_handler mgmt_handlers[] = {
 	{ NULL }, /* 0x0000 (no command) */
 	{ read_version,            MGMT_READ_VERSION_SIZE,
@@ -6411,6 +6664,8 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
 						HCI_MGMT_NO_HDEV |
 						HCI_MGMT_UNTRUSTED },
 	{ read_adv_features,       MGMT_READ_ADV_FEATURES_SIZE },
+	{ add_advertising,	   MGMT_ADD_ADVERTISING_SIZE,
+						HCI_MGMT_VAR_LEN },
 };
 
 void mgmt_index_added(struct hci_dev *hdev)
@@ -6582,7 +6837,8 @@ static int powered_update_hci(struct hci_dev *hdev)
 			update_scan_rsp_data(&req);
 		}
 
-		if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
+		if (hci_dev_test_flag(hdev, HCI_ADVERTISING) ||
+		    hci_dev_test_flag(hdev, HCI_ADVERTISING_INSTANCE))
 			enable_advertising(&req);
 
 		restart_le_actions(&req);
@@ -6694,7 +6950,13 @@ void mgmt_discoverable_timeout(struct hci_dev *hdev)
 			    sizeof(scan), &scan);
 	}
 	update_class(&req);
-	update_adv_data(&req);
+
+	/* Advertising instances don't use the global discoverable setting, so
+	 * only update AD if advertising was enabled using Set Advertising.
+	 */
+	if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
+		update_adv_data(&req);
+
 	hci_req_run(&req, NULL);
 
 	hdev->discov_timeout = 0;
@@ -7595,7 +7857,8 @@ void mgmt_reenable_advertising(struct hci_dev *hdev)
 {
 	struct hci_request req;
 
-	if (!hci_dev_test_flag(hdev, HCI_ADVERTISING))
+	if (!hci_dev_test_flag(hdev, HCI_ADVERTISING) &&
+	    !hci_dev_test_flag(hdev, HCI_ADVERTISING_INSTANCE))
 		return;
 
 	hci_req_init(&req, hdev);