From 4dab786482d706a2a41cd16cf174671d640a9870 Mon Sep 17 00:00:00 2001 From: Johan Hedberg Date: Thu, 7 Jun 2012 14:58:37 +0800 Subject: [PATCH] Bluetooth: Fix SMP security elevation from medium to high If we have an unauthenticated key it is not sufficient to acheive high security. Therefore, when deciding whether to encrypt the link or request pairing, it is essential to in addition to checking the existence of a key to also check whether it is authenticated or not. Signed-off-by: Johan Hedberg Signed-off-by: Gustavo Padovan --- net/bluetooth/smp.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index c4ac2849d9c2..37df4e9b3896 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -703,7 +703,7 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) return 0; } -static u8 smp_ltk_encrypt(struct l2cap_conn *conn) +static u8 smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) { struct smp_ltk *key; struct hci_conn *hcon = conn->hcon; @@ -712,6 +712,9 @@ static u8 smp_ltk_encrypt(struct l2cap_conn *conn) if (!key) return 0; + if (sec_level > BT_SECURITY_MEDIUM && !key->authenticated) + return 0; + if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) return 1; @@ -732,7 +735,7 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) hcon->pending_sec_level = authreq_to_seclevel(rp->auth_req); - if (smp_ltk_encrypt(conn)) + if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) return 0; if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) @@ -771,7 +774,7 @@ int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level) return 1; if (hcon->link_mode & HCI_LM_MASTER) - if (smp_ltk_encrypt(conn)) + if (smp_ltk_encrypt(conn, sec_level)) goto done; if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) -- 2.39.5