From: Marcel Holtmann marcel@holtmann.org
commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.
The minimum encryption key size for LE connections is 56 bits and to align LE with BR/EDR, enforce 56 bits of minimum encryption key size for BR/EDR connections as well.
Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Johan Hedberg johan.hedberg@intel.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/net/bluetooth/hci_core.h | 3 +++ net/bluetooth/hci_conn.c | 8 ++++++++ 2 files changed, 11 insertions(+)
--- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -176,6 +176,9 @@ struct adv_info {
#define HCI_MAX_SHORT_NAME_LENGTH 10
+/* Min encryption key size to match with SMP */ +#define HCI_MIN_ENC_KEY_SIZE 7 + /* Default LE RPA expiry time, 15 minutes */ #define HCI_DEFAULT_RPA_TIMEOUT (15 * 60)
--- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1165,6 +1165,14 @@ int hci_conn_check_link_mode(struct hci_ !test_bit(HCI_CONN_ENCRYPT, &conn->flags)) return 0;
+ /* The minimum encryption key size needs to be enforced by the + * host stack before establishing any L2CAP connections. The + * specification in theory allows a minimum of 1, but to align + * BR/EDR and LE transports, a minimum of 7 is chosen. + */ + if (conn->enc_key_size < HCI_MIN_ENC_KEY_SIZE) + return 0; + return 1; }