Milenage: 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>

src/crypto/milenage.c

@@ -217,7 +217,7 @@ int milenage_auts(const u8 *opc, const u8 *k, const u8 *_rand, const u8 *auts,
 	for (i = 0; i < 6; i++)
 		sqn[i] = auts[i] ^ ak[i];
 	if (milenage_f1(opc, k, _rand, sqn, amf, NULL, mac_s) ||
-	    memcmp(mac_s, auts + 6, 8) != 0)
+	    os_memcmp_const(mac_s, auts + 6, 8) != 0)
 		return -1;
 	return 0;
 }
@@ -312,7 +312,7 @@ int milenage_check(const u8 *opc, const u8 *k, const u8 *sqn, const u8 *_rand,
 
 	wpa_hexdump(MSG_DEBUG, "Milenage: MAC_A", mac_a, 8);
 
-	if (os_memcmp(mac_a, autn + 8, 8) != 0) {
+	if (os_memcmp_const(mac_a, autn + 8, 8) != 0) {
 		wpa_printf(MSG_DEBUG, "Milenage: MAC mismatch");
 		wpa_hexdump(MSG_DEBUG, "Milenage: Received MAC_A",
 			    autn + 8, 8);