diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index 6f875c2b51176c11f35e868b76c77270f5fde128..72105aec8054c8173e9ce28a9b8cfd64fef2991b 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -1722,6 +1722,7 @@ struct hci_conn_params *hci_pend_le_action_lookup(struct list_head *list, void hci_uuids_clear(struct hci_dev *hdev); void hci_link_keys_clear(struct hci_dev *hdev); +u8 *hci_conn_key_enc_size(struct hci_conn *conn); struct link_key *hci_find_link_key(struct hci_dev *hdev, bdaddr_t *bdaddr); struct link_key *hci_add_link_key(struct hci_dev *hdev, struct hci_conn *conn, bdaddr_t *bdaddr, u8 *val, u8 type, diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 549ee9e87d636664c1bb9f120d1a49f17eb2a685..38eb5d923ff89e459b0da4efbfc6b49a3104c443 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1015,6 +1015,30 @@ static struct hci_conn *__hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t return conn; } +u8 *hci_conn_key_enc_size(struct hci_conn *conn) +{ + if (conn->type == ACL_LINK) { + struct link_key *key; + + key = hci_find_link_key(conn->hdev, &conn->dst); + if (!key) + return NULL; + + return &key->pin_len; + } else if (conn->type == LE_LINK) { + struct smp_ltk *ltk; + + ltk = hci_find_ltk(conn->hdev, &conn->dst, conn->dst_type, + conn->role); + if (!ltk) + return NULL; + + return <k->enc_size; + } + + return NULL; +} + struct hci_conn *hci_conn_add_unset(struct hci_dev *hdev, int type, bdaddr_t *dst, u8 role) { diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 2e0a2ed1955d424338c0464830327ca14d182470..24aec718299502fe5a3cb0aadabce760a921400b 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -742,10 +742,17 @@ static u8 hci_cc_read_enc_key_size(struct hci_dev *hdev, void *data, handle); conn->enc_key_size = 0; } else { + u8 *key_enc_size = hci_conn_key_enc_size(conn); + conn->enc_key_size = rp->key_size; status = 0; - if (conn->enc_key_size < hdev->min_enc_key_size) { + /* Attempt to check if the key size is too small or if it has + * been downgraded from the last time it was stored as part of + * the link_key. + */ + if (conn->enc_key_size < hdev->min_enc_key_size || + (key_enc_size && conn->enc_key_size < *key_enc_size)) { /* As slave role, the conn->state has been set to * BT_CONNECTED and l2cap conn req might not be received * yet, at this moment the l2cap layer almost does @@ -758,6 +765,10 @@ static u8 hci_cc_read_enc_key_size(struct hci_dev *hdev, void *data, clear_bit(HCI_CONN_ENCRYPT, &conn->flags); clear_bit(HCI_CONN_AES_CCM, &conn->flags); } + + /* Update the key encryption size with the connection one */ + if (key_enc_size && *key_enc_size != conn->enc_key_size) + *key_enc_size = conn->enc_key_size; } hci_encrypt_cfm(conn, status); @@ -3068,6 +3079,34 @@ static void hci_inquiry_result_evt(struct hci_dev *hdev, void *edata, hci_dev_unlock(hdev); } +static int hci_read_enc_key_size(struct hci_dev *hdev, struct hci_conn *conn) +{ + struct hci_cp_read_enc_key_size cp; + u8 *key_enc_size = hci_conn_key_enc_size(conn); + + if (!read_key_size_capable(hdev)) { + conn->enc_key_size = HCI_LINK_KEY_SIZE; + return -EOPNOTSUPP; + } + + bt_dev_dbg(hdev, "hcon %p", conn); + + memset(&cp, 0, sizeof(cp)); + cp.handle = cpu_to_le16(conn->handle); + + /* If the key enc_size is already known, use it as conn->enc_key_size, + * otherwise use hdev->min_enc_key_size so the likes of + * l2cap_check_enc_key_size don't fail while waiting for + * HCI_OP_READ_ENC_KEY_SIZE response. + */ + if (key_enc_size && *key_enc_size) + conn->enc_key_size = *key_enc_size; + else + conn->enc_key_size = hdev->min_enc_key_size; + + return hci_send_cmd(hdev, HCI_OP_READ_ENC_KEY_SIZE, sizeof(cp), &cp); +} + static void hci_conn_complete_evt(struct hci_dev *hdev, void *data, struct sk_buff *skb) { @@ -3160,23 +3199,11 @@ static void hci_conn_complete_evt(struct hci_dev *hdev, void *data, if (ev->encr_mode == 1 && !test_bit(HCI_CONN_ENCRYPT, &conn->flags) && ev->link_type == ACL_LINK) { struct link_key *key; - struct hci_cp_read_enc_key_size cp; key = hci_find_link_key(hdev, &ev->bdaddr); if (key) { set_bit(HCI_CONN_ENCRYPT, &conn->flags); - - if (!read_key_size_capable(hdev)) { - conn->enc_key_size = HCI_LINK_KEY_SIZE; - } else { - cp.handle = cpu_to_le16(conn->handle); - if (hci_send_cmd(hdev, HCI_OP_READ_ENC_KEY_SIZE, - sizeof(cp), &cp)) { - bt_dev_err(hdev, "sending read key size failed"); - conn->enc_key_size = HCI_LINK_KEY_SIZE; - } - } - + hci_read_enc_key_size(hdev, conn); hci_encrypt_cfm(conn, ev->status); } } @@ -3615,24 +3642,8 @@ static void hci_encrypt_change_evt(struct hci_dev *hdev, void *data, /* Try reading the encryption key size for encrypted ACL links */ if (!ev->status && ev->encrypt && conn->type == ACL_LINK) { - struct hci_cp_read_enc_key_size cp; - - /* Only send HCI_Read_Encryption_Key_Size if the - * controller really supports it. If it doesn't, assume - * the default size (16). - */ - if (!read_key_size_capable(hdev)) { - conn->enc_key_size = HCI_LINK_KEY_SIZE; - goto notify; - } - - cp.handle = cpu_to_le16(conn->handle); - if (hci_send_cmd(hdev, HCI_OP_READ_ENC_KEY_SIZE, - sizeof(cp), &cp)) { - bt_dev_err(hdev, "sending read key size failed"); - conn->enc_key_size = HCI_LINK_KEY_SIZE; + if (hci_read_enc_key_size(hdev, conn)) goto notify; - } goto unlock; } diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 8d6fc186950334c7b572fa7323dcf8f2d7dca0ce..a4ba69331708aa3eeefd0c0f9e2df2bc62c155d9 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1411,7 +1411,8 @@ static void l2cap_request_info(struct l2cap_conn *conn) sizeof(req), &req); } -static bool l2cap_check_enc_key_size(struct hci_conn *hcon) +static bool l2cap_check_enc_key_size(struct hci_conn *hcon, + struct l2cap_chan *chan) { /* The minimum encryption key size needs to be enforced by the * host stack before establishing any L2CAP connections. The @@ -1425,7 +1426,7 @@ static bool l2cap_check_enc_key_size(struct hci_conn *hcon) int min_key_size = hcon->hdev->min_enc_key_size; /* On FIPS security level, key size must be 16 bytes */ - if (hcon->sec_level == BT_SECURITY_FIPS) + if (chan->sec_level == BT_SECURITY_FIPS) min_key_size = 16; return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) || @@ -1453,7 +1454,7 @@ static void l2cap_do_start(struct l2cap_chan *chan) !__l2cap_no_conn_pending(chan)) return; - if (l2cap_check_enc_key_size(conn->hcon)) + if (l2cap_check_enc_key_size(conn->hcon, chan)) l2cap_start_connection(chan); else __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); @@ -1528,7 +1529,7 @@ static void l2cap_conn_start(struct l2cap_conn *conn) continue; } - if (l2cap_check_enc_key_size(conn->hcon)) + if (l2cap_check_enc_key_size(conn->hcon, chan)) l2cap_start_connection(chan); else l2cap_chan_close(chan, ECONNREFUSED); @@ -3954,7 +3955,8 @@ static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, /* Check if the ACL is secure enough (if not SDP) */ if (psm != cpu_to_le16(L2CAP_PSM_SDP) && - !hci_conn_check_link_mode(conn->hcon)) { + (!hci_conn_check_link_mode(conn->hcon) || + !l2cap_check_enc_key_size(conn->hcon, pchan))) { conn->disc_reason = HCI_ERROR_AUTH_FAILURE; result = L2CAP_CR_SEC_BLOCK; goto response; @@ -7322,7 +7324,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) } if (chan->state == BT_CONNECT) { - if (!status && l2cap_check_enc_key_size(hcon)) + if (!status && l2cap_check_enc_key_size(hcon, chan)) l2cap_start_connection(chan); else __set_chan_timer(chan, L2CAP_DISC_TIMEOUT); @@ -7332,7 +7334,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt) struct l2cap_conn_rsp rsp; __u16 res, stat; - if (!status && l2cap_check_enc_key_size(hcon)) { + if (!status && l2cap_check_enc_key_size(hcon, chan)) { if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) { res = L2CAP_CR_PEND; stat = L2CAP_CS_AUTHOR_PEND;