Bluetooth: Use the LTK after receiving a LE Security Request

When receiving a security request from the remote device we should find
if there is already a LTK associated with the remote device, if found
we should use it to encrypt the link.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

1 files changed, 28 insertions, 18 deletions

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 7e558465133f..8a7eaaedd67a 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -499,6 +499,29 @@ 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)
+{
+        struct link_key *key;
+        struct key_master_id *master;
+        struct hci_conn *hcon = conn->hcon;
+
+        key = hci_find_link_key_type(hcon->hdev, conn->dst,
+                                                HCI_LK_SMP_LTK);
+        if (!key)
+                return 0;
+
+        if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND,
+                                        &hcon->pend))
+                return 1;
+
+        master = (void *) key->data;
+        hci_le_start_enc(hcon, master->ediv, master->rand,
+                                                key->val);
+        hcon->enc_key_size = key->pin_len;
+
+        return 1;
+
+}
 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
 {
         struct smp_cmd_security_req *rp = (void *) skb->data;
@@ -508,6 +531,9 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
 
         BT_DBG("conn %p", conn);
 
+        if (smp_ltk_encrypt(conn))
+                return 0;
+
         if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend))
                 return 0;
 
@@ -542,25 +568,9 @@ int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
         if (hcon->sec_level >= sec_level)
                 return 1;
 
-        if (hcon->link_mode & HCI_LM_MASTER) {
-                struct link_key *key;
-
-                key = hci_find_link_key_type(hcon->hdev, conn->dst,
-                                                        HCI_LK_SMP_LTK);
-                if (key) {
-                        struct key_master_id *master = (void *) key->data;
-
-                        if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND,
-                                                        &hcon->pend))
-                                goto done;
-
-                        hci_le_start_enc(hcon, master->ediv, master->rand,
-                                                                key->val);
-                        hcon->enc_key_size = key->pin_len;
-
+        if (hcon->link_mode & HCI_LM_MASTER)
+                if (smp_ltk_encrypt(conn))
                         goto done;
-                }
-        }
 
         if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend))
                 return 0;