From 288c06973daae4637f25a0d1bdaf65fdbf8455f9 Mon Sep 17 00:00:00 2001 From: Archie Pusaka Date: Wed, 11 Nov 2020 14:32:20 +0800 Subject: [PATCH] Bluetooth: Enforce key size of 16 bytes on FIPS level According to the spec Ver 5.2, Vol 3, Part C, Sec 5.2.2.8: Device in security mode 4 level 4 shall enforce: 128-bit equivalent strength for link and encryption keys required using FIPS approved algorithms (E0 not allowed, SAFER+ not allowed, and P-192 not allowed; encryption key not shortened) This patch rejects connection with key size below 16 for FIPS level services. Signed-off-by: Archie Pusaka Reviewed-by: Alain Michaud Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap_core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 1ab27b90ddcb..5817f5c2ec18 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1515,8 +1515,14 @@ static bool l2cap_check_enc_key_size(struct hci_conn *hcon) * that have no key size requirements. Ensure that the link is * actually encrypted before enforcing a key size. */ + 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) + min_key_size = 16; + return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) || - hcon->enc_key_size >= hcon->hdev->min_enc_key_size); + hcon->enc_key_size >= min_key_size); } static void l2cap_do_start(struct l2cap_chan *chan)