EAP-GTC: Use os_memcmp_const() for hash/password comparisons

This makes the implementation less likely to provide useful timing
information to potential attackers from comparisons of information
received from a remote device and private material known only by the
authorized devices.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/eap_server/eap_server_gtc.c b/src/eap_server/eap_server_gtc.c
index f423106bfc9c861480f8055191b54f231cab7a2e..98ac3c6ec49585043269283bfada465bd8cd82a8 100644 (file)
--- a/src/eap_server/eap_server_gtc.c
+++ b/src/eap_server/eap_server_gtc.c
@@ -175,7 +175,7 @@ static void eap_gtc_process(struct eap_sm *sm, void *priv,
        }
 
        if (rlen != sm->user->password_len ||
-           os_memcmp(pos, sm->user->password, rlen) != 0) {
+           os_memcmp_const(pos, sm->user->password, rlen) != 0) {
                wpa_printf(MSG_DEBUG, "EAP-GTC: Done - Failure");
                data->state = FAILURE;
        } else {