DGNum/hostapd
6
0
Fork 0
Code Issues Pull requests 1 Projects Releases Packages Wiki Activity Actions

SAE: Add processing of the confirm message

Browse source 
This adds validation of the received confirm messages for SAE.

Signed-hostap: Jouni Malinen <j@w1.fi>
This commit is contained in:
Jouni Malinen 2012-12-30 22:31:19 +02:00
parent fb8fcc2950
commit f2e9818f73
4 changed files with 56 additions and 36 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

26
src/ap/ieee802_11.c
View file

@ -365,22 +365,6 @@ static struct wpabuf * auth_build_sae_confirm(struct hostapd_data *hapd,
}
static u16 handle_sae_confirm(struct hostapd_data *hapd, struct sta_info *sta,
const u8 *data, size_t len)
{
u16 rc;
wpa_hexdump(MSG_DEBUG, "SAE confirm fields", data, len);
if (len < 2)
return WLAN_STATUS_UNSPECIFIED_FAILURE;
rc = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "SAE: peer-send-confirm %u", rc);
return WLAN_STATUS_SUCCESS;
}
static void handle_auth_sae(struct hostapd_data *hapd, struct sta_info *sta,
const struct ieee80211_mgmt *mgmt, size_t len,
u8 auth_transaction)
@ -418,10 +402,12 @@ static void handle_auth_sae(struct hostapd_data *hapd, struct sta_info *sta,
hostapd_logger(hapd, sta->addr, HOSTAPD_MODULE_IEEE80211,
HOSTAPD_LEVEL_DEBUG,
"SAE authentication (RX confirm)");
resp = handle_sae_confirm(hapd, sta, mgmt->u.auth.variable,
((u8 *) mgmt) + len -
mgmt->u.auth.variable);
if (resp == WLAN_STATUS_SUCCESS) {
if (sae_check_confirm(sta->sae, mgmt->u.auth.variable,
((u8 *) mgmt) + len -
mgmt->u.auth.variable) < 0) {
resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
} else {
resp = WLAN_STATUS_SUCCESS;
sta->flags |= WLAN_STA_AUTH;
wpa_auth_sm_event(sta->wpa_sm, WPA_AUTH);
sta->auth_alg = WLAN_AUTH_SAE;

48
src/common/sae.c
View file

@ -574,3 +574,51 @@ void sae_write_confirm(struct sae_data *sae, struct wpabuf *buf)
hmac_sha256_vector(sae->kck, sizeof(sae->kck), 5, addr, len,
wpabuf_put(buf, SHA256_MAC_LEN));
}
int sae_check_confirm(struct sae_data *sae, const u8 *data, size_t len)
{
u16 rc;
const u8 *addr[5];
size_t elen[5];
u8 verifier[SHA256_MAC_LEN];
wpa_hexdump(MSG_DEBUG, "SAE: Confirm fields", data, len);
if (len < 2 + SHA256_MAC_LEN) {
wpa_printf(MSG_DEBUG, "SAE: Too short confirm message");
return -1;
}
rc = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "SAE: peer-send-confirm %u", rc);
/* Confirm
* CN(key, X, Y, Z, ...) =
* HMAC-SHA256(key, D2OS(X) || D2OS(Y) || D2OS(Z) | ...)
* verifier = CN(KCK, peer-send-confirm, peer-commit-scalar,
* PEER-COMMIT-ELEMENT, commit-scalar, COMMIT-ELEMENT)
*/
addr[0] = data;
elen[0] = 2;
addr[1] = sae->peer_commit_scalar;
elen[1] = 32;
addr[2] = sae->peer_commit_element;
elen[2] = 2 * 32;
addr[3] = sae->own_commit_scalar;
elen[3] = 32;
addr[4] = sae->own_commit_element;
elen[4] = 2 * 32;
hmac_sha256_vector(sae->kck, sizeof(sae->kck), 5, addr, elen, verifier);
if (os_memcmp(verifier, data + 2, SHA256_MAC_LEN) != 0) {
wpa_printf(MSG_DEBUG, "SAE: Confirm mismatch");
wpa_hexdump(MSG_DEBUG, "SAE: Received confirm",
data + 2, SHA256_MAC_LEN);
wpa_hexdump(MSG_DEBUG, "SAE: Calculated verifier",
verifier, SHA256_MAC_LEN);
return -1;
}
return 0;
}

1
src/common/sae.h
View file

@ -32,5 +32,6 @@ int sae_process_commit(struct sae_data *sae);
void sae_write_commit(struct sae_data *sae, struct wpabuf *buf);
u16 sae_parse_commit(struct sae_data *sae, const u8 *data, size_t len);
void sae_write_confirm(struct sae_data *sae, struct wpabuf *buf);
int sae_check_confirm(struct sae_data *sae, const u8 *data, size_t len);
#endif /* SAE_H */

17
wpa_supplicant/sme.c
View file

@ -399,21 +399,6 @@ void sme_authenticate(struct wpa_supplicant *wpa_s,
#ifdef CONFIG_SAE
static int sme_sae_process_confirm(struct wpa_supplicant *wpa_s, const u8 *data,
size_t len)
{
u16 rc;
if (len < 2)
return -1;
rc = WPA_GET_LE16(data);
wpa_printf(MSG_DEBUG, "SAE: peer-send-confirm %u", rc);
/* TODO */
return 0;
}
static int sme_sae_auth(struct wpa_supplicant *wpa_s, u16 auth_transaction,
u16 status_code, const u8 *data, size_t len)
{
@ -448,7 +433,7 @@ static int sme_sae_auth(struct wpa_supplicant *wpa_s, u16 auth_transaction,
wpa_dbg(wpa_s, MSG_DEBUG, "SME SAE confirm");
if (wpa_s->sme.sae.state != SAE_CONFIRM)
return -1;
if (sme_sae_process_confirm(wpa_s, data, len) < 0)
if (sae_check_confirm(&wpa_s->sme.sae, data, len) < 0)
return -1;
return 1;
}