Bluetooth: Add support for pairing via mgmt over LE

Using the advertising cache we are able to infer the type
of the remote device, and so trigger pairing over the correct
link type.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/mgmt.c

@@ -1347,6 +1347,7 @@ static int pair_device(struct sock *sk, u16 index, unsigned char *data, u16 len)
 	struct hci_dev *hdev;
 	struct mgmt_cp_pair_device *cp;
 	struct pending_cmd *cmd;
+	struct adv_entry *entry;
 	u8 sec_level, auth_type;
 	struct hci_conn *conn;
 	int err;
@@ -1372,7 +1373,14 @@ static int pair_device(struct sock *sk, u16 index, unsigned char *data, u16 len)
 		auth_type = HCI_AT_DEDICATED_BONDING_MITM;
 	}
 
-	conn = hci_connect(hdev, ACL_LINK, &cp->bdaddr, sec_level, auth_type);
+	entry = hci_find_adv_entry(hdev, &cp->bdaddr);
+	if (entry)
+		conn = hci_connect(hdev, LE_LINK, &cp->bdaddr, sec_level,
+								auth_type);
+	else
+		conn = hci_connect(hdev, ACL_LINK, &cp->bdaddr, sec_level,
+								auth_type);
+
 	if (IS_ERR(conn)) {
 		err = PTR_ERR(conn);
 		goto unlock;
@@ -1391,7 +1399,10 @@ static int pair_device(struct sock *sk, u16 index, unsigned char *data, u16 len)
 		goto unlock;
 	}
 
+	/* For LE, just connecting isn't a proof that the pairing finished */
+	if (!entry)
 		conn->connect_cfm_cb = pairing_complete_cb;
+
 	conn->security_cfm_cb = pairing_complete_cb;
 	conn->disconn_cfm_cb = pairing_complete_cb;
 	conn->io_capability = cp->io_cap;