EAP-SAKE: 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/eap_peer/eap_sake.c

@@ -315,7 +315,7 @@ static struct wpabuf * eap_sake_process_confirm(struct eap_sm *sm,
 			     data->peerid, data->peerid_len, 0,
 			     wpabuf_head(reqData), wpabuf_len(reqData),
 			     attr.mic_s, mic_s);
-	if (os_memcmp(attr.mic_s, mic_s, EAP_SAKE_MIC_LEN) != 0) {
+	if (os_memcmp_const(attr.mic_s, mic_s, EAP_SAKE_MIC_LEN) != 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_S");
 		eap_sake_state(data, FAILURE);
 		ret->methodState = METHOD_DONE;

src/eap_server/eap_server_sake.c

@@ -351,7 +351,7 @@ static void eap_sake_process_challenge(struct eap_sm *sm,
 			     data->peerid, data->peerid_len, 1,
 			     wpabuf_head(respData), wpabuf_len(respData),
 			     attr.mic_p, mic_p);
-	if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
+	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
 		eap_sake_state(data, FAILURE);
 		return;
@@ -388,7 +388,7 @@ static void eap_sake_process_confirm(struct eap_sm *sm,
 			     data->peerid, data->peerid_len, 1,
 			     wpabuf_head(respData), wpabuf_len(respData),
 			     attr.mic_p, mic_p);
-	if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
+	if (os_memcmp_const(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
 		wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
 		eap_sake_state(data, FAILURE);
 	} else