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>
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 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 ---- */