[Bluetooth] Export details about authentication requirements

With the Simple Pairing support, the authentication requirements are
an explicit setting during the bonding process. Track and enforce the
requirements and allow higher layers like L2CAP and RFCOMM to increase
them if needed.

This patch introduces a new IOCTL that allows to query the current
authentication requirements. It is also possible to detect Simple
Pairing support in the kernel this way.

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

1 files changed, 10 insertions, 4 deletions

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 2522640..30ad59b 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -2150,7 +2150,7 @@ static int l2cap_disconn_ind(struct hci_conn *hcon, u8 reason)
 static int l2cap_auth_cfm(struct hci_conn *hcon, u8 status)
 {
 	struct l2cap_chan_list *l;
-	struct l2cap_conn *conn = conn = hcon->l2cap_data;
+	struct l2cap_conn *conn = hcon->l2cap_data;
 	struct l2cap_conn_rsp rsp;
 	struct sock *sk;
 	int result;
@@ -2165,11 +2165,17 @@ static int l2cap_auth_cfm(struct hci_conn *hcon, u8 status)
 	read_lock(&l->lock);
 
 	for (sk = l->head; sk; sk = l2cap_pi(sk)->next_c) {
+		struct l2cap_pinfo *pi = l2cap_pi(sk);
+
 		bh_lock_sock(sk);
 
-		if (sk->sk_state != BT_CONNECT2 ||
-				(l2cap_pi(sk)->link_mode & L2CAP_LM_ENCRYPT) ||
-				(l2cap_pi(sk)->link_mode & L2CAP_LM_SECURE)) {
+		if (sk->sk_state != BT_CONNECT2) {
+			bh_unlock_sock(sk);
+			continue;
+		}
+
+		if ((pi->link_mode & (L2CAP_LM_ENCRYPT | L2CAP_LM_SECURE)) &&
+					!(hcon->link_mode & HCI_LM_ENCRYPT)) {
 			bh_unlock_sock(sk);
 			continue;
 		}