[PATCH v3 1/2] Bluetooth: Send device found event on name resolve failure

[Archie Pusaka <apusaka@google.com>]

From: Archie Pusaka <apusaka@chromium.org>

Introducing NAME_REQUEST_FAILED flag that will be sent together with
device found event on name resolve failure. This will provide the
userspace with an information so it can decide not to resolve the
name for these devices in the future.

Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

---
Hi maintainers,

This is the patch series for remote name request as was discussed here.
https://patchwork.kernel.org/project/bluetooth/patch/20211028191805.1.I35b7f3a496f834de6b43a32f94b6160cb1467c94@changeid/
Please also review the corresponding userspace change.

Thanks,
Archie

Changes in v3:
* Reindent defines
* Assign variables inside if block instead of initializing

Changes in v2:
* Remove the part which accepts DONT_CARE flag in MGMT_OP_CONFIRM_NAME
* Rename MGMT constant to conform with the docs

 include/net/bluetooth/mgmt.h |  9 +++++----
 net/bluetooth/hci_event.c    | 11 ++++-------
 net/bluetooth/mgmt.c         | 12 ++++++++++--
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 23a0524061b7..107b25deae68 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -936,10 +936,11 @@ struct mgmt_ev_auth_failed {
 	__u8	status;
 } __packed;
 
-#define MGMT_DEV_FOUND_CONFIRM_NAME    0x01
-#define MGMT_DEV_FOUND_LEGACY_PAIRING  0x02
-#define MGMT_DEV_FOUND_NOT_CONNECTABLE 0x04
-#define MGMT_DEV_FOUND_INITIATED_CONN  0x08
+#define MGMT_DEV_FOUND_CONFIRM_NAME		0x01
+#define MGMT_DEV_FOUND_LEGACY_PAIRING		0x02
+#define MGMT_DEV_FOUND_NOT_CONNECTABLE		0x04
+#define MGMT_DEV_FOUND_INITIATED_CONN		0x08
+#define MGMT_DEV_FOUND_NAME_REQUEST_FAILED	0x10
 
 #define MGMT_EV_DEVICE_FOUND		0x0012
 struct mgmt_ev_device_found {
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index dee4ef22fc88..bb4c04aecccf 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -2175,13 +2175,10 @@ static void hci_check_pending_name(struct hci_dev *hdev, struct hci_conn *conn,
 		return;
 
 	list_del(&e->list);
-	if (name) {
-		e->name_state = NAME_KNOWN;
-		mgmt_remote_name(hdev, bdaddr, ACL_LINK, 0x00,
-				 e->data.rssi, name, name_len);
-	} else {
-		e->name_state = NAME_NOT_KNOWN;
-	}
+
+	e->name_state = name ? NAME_KNOWN : NAME_NOT_KNOWN;
+	mgmt_remote_name(hdev, bdaddr, ACL_LINK, 0x00, e->data.rssi,
+			 name, name_len);
 
 	if (hci_resolve_next_name(hdev))
 		return;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index f8f74d344297..bf989ae03f9f 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -9615,6 +9615,7 @@ void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 	struct mgmt_ev_device_found *ev;
 	char buf[sizeof(*ev) + HCI_MAX_NAME_LENGTH + 2];
 	u16 eir_len;
+	u32 flags;
 
 	ev = (struct mgmt_ev_device_found *) buf;
 
@@ -9624,10 +9625,17 @@ void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 	ev->addr.type = link_to_bdaddr(link_type, addr_type);
 	ev->rssi = rssi;
 
-	eir_len = eir_append_data(ev->eir, 0, EIR_NAME_COMPLETE, name,
-				  name_len);
+	if (name) {
+		eir_len = eir_append_data(ev->eir, 0, EIR_NAME_COMPLETE, name,
+					  name_len);
+		flags = 0;
+	} else {
+		eir_len = 0;
+		flags = MGMT_DEV_FOUND_NAME_REQUEST_FAILED;
+	}
 
 	ev->eir_len = cpu_to_le16(eir_len);
+	ev->flags = cpu_to_le32(flags);
 
 	mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, sizeof(*ev) + eir_len, NULL);
 }
-- 
2.34.0.rc2.393.gf8c9666880-goog