Bluetooth: Use general bonding whenever possible

When receiving incoming connection to specific services, always use
general bonding. This ensures that the link key gets stored and can be
used for further authentications.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

4 files changed, 40 insertions, 17 deletions

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 4b14972..f75028b 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -328,7 +328,7 @@ void hci_conn_check_pending(struct hci_dev *hdev);
 
 struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8 sec_level, __u8 auth_type);
 int hci_conn_check_link_mode(struct hci_conn *conn);
-int hci_conn_security(struct hci_conn *conn, __u8 sec_level);
+int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
 int hci_conn_change_link_key(struct hci_conn *conn);
 int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
 
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 2435e83..7fc4c04 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -391,19 +391,14 @@ int hci_conn_check_link_mode(struct hci_conn *conn)
 EXPORT_SYMBOL(hci_conn_check_link_mode);
 
 /* Authenticate remote device */
-static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level)
+static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
 {
 	BT_DBG("conn %p", conn);
 
-	if (sec_level > conn->sec_level)
-		conn->link_mode &= ~HCI_LM_AUTH;
-
-	conn->sec_level = sec_level;
-
-	if (sec_level == BT_SECURITY_HIGH)
-		conn->auth_type |= 0x01;
-
-	if (conn->link_mode & HCI_LM_AUTH)
+	if (sec_level > conn->sec_level) {
+		conn->sec_level = sec_level;
+		conn->auth_type = auth_type;
+	} else if (conn->link_mode & HCI_LM_AUTH)
 		return 1;
 
 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->pend)) {
@@ -417,7 +412,7 @@ static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level)
 }
 
 /* Enable security */
-int hci_conn_security(struct hci_conn *conn, __u8 sec_level)
+int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
 {
 	BT_DBG("conn %p", conn);
 
@@ -426,18 +421,18 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level)
 
 	if (sec_level == BT_SECURITY_LOW) {
 		if (conn->ssp_mode > 0 && conn->hdev->ssp_mode > 0)
-			return hci_conn_auth(conn, sec_level);
+			return hci_conn_auth(conn, sec_level, auth_type);
 		else
 			return 1;
 	}
 
 	if (conn->link_mode & HCI_LM_ENCRYPT)
-		return hci_conn_auth(conn, sec_level);
+		return hci_conn_auth(conn, sec_level, auth_type);
 
 	if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
 		return 0;
 
-	if (hci_conn_auth(conn, sec_level)) {
+	if (hci_conn_auth(conn, sec_level, auth_type)) {
 		struct hci_cp_set_conn_encrypt cp;
 		cp.handle  = cpu_to_le16(conn->handle);
 		cp.encrypt = 1;
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index b677af6..8a93dde 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -263,8 +263,22 @@ static void l2cap_chan_del(struct sock *sk, int err)
 static inline int l2cap_check_security(struct sock *sk)
 {
 	struct l2cap_conn *conn = l2cap_pi(sk)->conn;
+	__u8 auth_type;
+
+	switch (l2cap_pi(sk)->sec_level) {
+	case BT_SECURITY_HIGH:
+		auth_type = HCI_AT_GENERAL_BONDING_MITM;
+		break;
+	case BT_SECURITY_MEDIUM:
+		auth_type = HCI_AT_GENERAL_BONDING;
+		break;
+	default:
+		auth_type = HCI_AT_NO_BONDING;
+		break;
+	}
 
-	return hci_conn_security(conn->hcon, l2cap_pi(sk)->sec_level);
+	return hci_conn_security(conn->hcon, l2cap_pi(sk)->sec_level,
+								auth_type);
 }
 
 static inline u8 l2cap_get_ident(struct l2cap_conn *conn)
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 3717c25..1828ec0 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -226,8 +226,22 @@ static int rfcomm_l2sock_create(struct socket **sock)
 static inline int rfcomm_check_security(struct rfcomm_dlc *d)
 {
 	struct sock *sk = d->session->sock->sk;
+	__u8 auth_type;
 
-	return hci_conn_security(l2cap_pi(sk)->conn->hcon, d->sec_level);
+	switch (d->sec_level) {
+	case BT_SECURITY_HIGH:
+		auth_type = HCI_AT_GENERAL_BONDING_MITM;
+		break;
+	case BT_SECURITY_MEDIUM:
+		auth_type = HCI_AT_GENERAL_BONDING;
+		break;
+	default:
+		auth_type = HCI_AT_NO_BONDING;
+		break;
+	}
+
+	return hci_conn_security(l2cap_pi(sk)->conn->hcon, d->sec_level,
+								auth_type);
 }
 
 /* ---- RFCOMM DLCs ---- */