diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 76045497eaa1..a37f809591ad 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5391,7 +5391,8 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn, mutex_lock(&conn->chan_lock); l2cap_chan_lock(pchan); - if (!smp_sufficient_security(conn->hcon, pchan->sec_level)) { + if (!smp_sufficient_security(conn->hcon, pchan->sec_level, + SMP_ALLOW_STK)) { result = L2CAP_CR_AUTHENTICATION; chan = NULL; goto response_unlock; diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index 3b63c7f09dd5..3dc5f0e66405 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -1122,18 +1122,20 @@ static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) return true; } -bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level) +bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, + enum smp_key_pref key_pref) { if (sec_level == BT_SECURITY_LOW) return true; - /* If we're encrypted with an STK always claim insufficient - * security. This way we allow the connection to be re-encrypted - * with an LTK, even if the LTK provides the same level of - * security. Only exception is if we don't have an LTK (e.g. - * because of key distribution bits). + /* If we're encrypted with an STK but the caller prefers using + * LTK claim insufficient security. This way we allow the + * connection to be re-encrypted with an LTK, even if the LTK + * provides the same level of security. Only exception is if we + * don't have an LTK (e.g. because of key distribution bits). */ - if (test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && + if (key_pref == SMP_USE_LTK && + test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) return false; @@ -1167,7 +1169,7 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) else sec_level = authreq_to_seclevel(auth); - if (smp_sufficient_security(hcon, sec_level)) + if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) return 0; if (sec_level > hcon->pending_sec_level) @@ -1217,7 +1219,7 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) return 1; - if (smp_sufficient_security(hcon, sec_level)) + if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) return 1; if (sec_level > hcon->pending_sec_level) diff --git a/net/bluetooth/smp.h b/net/bluetooth/smp.h index 86a683a8b491..f76083b85005 100644 --- a/net/bluetooth/smp.h +++ b/net/bluetooth/smp.h @@ -133,8 +133,15 @@ static inline u8 smp_ltk_sec_level(struct smp_ltk *key) return BT_SECURITY_MEDIUM; } +/* Key preferences for smp_sufficient security */ +enum smp_key_pref { + SMP_ALLOW_STK, + SMP_USE_LTK, +}; + /* SMP Commands */ -bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level); +bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, + enum smp_key_pref key_pref); int smp_conn_security(struct hci_conn *hcon, __u8 sec_level); int smp_user_confirm_reply(struct hci_conn *conn, u16 mgmt_op, __le32 passkey);