static struct wpabuf * eap_eke_build_confirm(struct eap_sm *sm,
struct eap_eke_data *data, u8 id)
{
struct wpabuf *msg;
size_t plen, prot_len;
u8 nonces[2 * EAP_EKE_MAX_NONCE_LEN];
u8 *auth;
wpa_printf(MSG_DEBUG, "EAP-EKE: Request/Confirm");
plen = data->sess.pnonce_ps_len + data->sess.prf_len;
msg = eap_eke_build_msg(data, id, plen, EAP_EKE_CONFIRM);
if (msg == NULL) {
eap_eke_fail(data, EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
return eap_eke_build_failure(data, id);
}
if (random_get_bytes(data->nonce_s, data->sess.nonce_len)) {
wpabuf_free(msg);
eap_eke_fail(data, EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
return eap_eke_build_failure(data, id);
}
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Nonce_S",
data->nonce_s, data->sess.nonce_len);
os_memcpy(nonces, data->nonce_p, data->sess.nonce_len);
os_memcpy(nonces + data->sess.nonce_len, data->nonce_s,
data->sess.nonce_len);
prot_len = wpabuf_tailroom(msg);
if (eap_eke_prot(&data->sess, nonces, 2 * data->sess.nonce_len,
wpabuf_put(msg, 0), &prot_len) < 0) {
wpabuf_free(msg);
eap_eke_fail(data, EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
return eap_eke_build_failure(data, id);
}
wpabuf_put(msg, prot_len);
if (eap_eke_derive_ka(&data->sess,
sm->server_id, sm->server_id_len,
data->peerid, data->peerid_len,
data->nonce_p, data->nonce_s) < 0) {
wpabuf_free(msg);
eap_eke_fail(data, EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
return eap_eke_build_failure(data, id);
}
auth = wpabuf_put(msg, data->sess.prf_len);
if (eap_eke_auth(&data->sess, "EAP-EKE server", data->msgs, auth) < 0) {
wpabuf_free(msg);
eap_eke_fail(data, EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
return eap_eke_build_failure(data, id);
}
wpa_hexdump(MSG_DEBUG, "EAP-EKE: Auth_S", auth, data->sess.prf_len);
return msg;
}
static struct wpabuf * eap_eke_process_confirm(struct eap_eke_data *data,
struct eap_method_ret *ret,
const struct wpabuf *reqData,
const u8 *payload,
size_t payload_len)
{
struct wpabuf *resp;
const u8 *pos, *end;
size_t prot_len;
u8 nonces[2 * EAP_EKE_MAX_NONCE_LEN];
u8 auth_s[EAP_EKE_MAX_HASH_LEN];
size_t decrypt_len;
u8 *auth;
u8 id = eap_get_id(reqData);
if (data->state != CONFIRM) {
wpa_printf(MSG_DEBUG, "EAP-EKE: EAP-EKE-Confirm/Request received in unexpected state (%d)",
data->state);
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PROTO_ERROR);
}
wpa_printf(MSG_DEBUG, "EAP-EKE: Received EAP-EKE-Confirm/Request");
pos = payload;
end = payload + payload_len;
if (pos + data->sess.pnonce_ps_len + data->sess.prf_len > end) {
wpa_printf(MSG_DEBUG, "EAP-EKE: Too short EAP-EKE-Confirm");
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PROTO_ERROR);
}
decrypt_len = sizeof(nonces);
if (eap_eke_decrypt_prot(&data->sess, pos, data->sess.pnonce_ps_len,
nonces, &decrypt_len) < 0) {
wpa_printf(MSG_INFO, "EAP-EKE: Failed to decrypt PNonce_PS");
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_AUTHENTICATION_FAIL);
}
if (decrypt_len != (size_t) 2 * data->sess.nonce_len) {
wpa_printf(MSG_INFO, "EAP-EKE: PNonce_PS protected data length does not match length of Nonce_P and Nonce_S");
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_AUTHENTICATION_FAIL);
}
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Received Nonce_P | Nonce_S",
nonces, 2 * data->sess.nonce_len);
if (os_memcmp(data->nonce_p, nonces, data->sess.nonce_len) != 0) {
wpa_printf(MSG_INFO, "EAP-EKE: Received Nonce_P does not match transmitted Nonce_P");
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_AUTHENTICATION_FAIL);
}
os_memcpy(data->nonce_s, nonces + data->sess.nonce_len,
data->sess.nonce_len);
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Nonce_S",
data->nonce_s, data->sess.nonce_len);
if (eap_eke_derive_ka(&data->sess, data->serverid, data->serverid_len,
data->peerid, data->peerid_len,
data->nonce_p, data->nonce_s) < 0) {
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
if (eap_eke_auth(&data->sess, "EAP-EKE server", data->msgs, auth_s) < 0)
{
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
wpa_hexdump(MSG_DEBUG, "EAP-EKE: Auth_S", auth_s, data->sess.prf_len);
if (os_memcmp_const(auth_s, pos + data->sess.pnonce_ps_len,
data->sess.prf_len) != 0) {
wpa_printf(MSG_INFO, "EAP-EKE: Auth_S does not match");
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_AUTHENTICATION_FAIL);
}
wpa_printf(MSG_DEBUG, "EAP-EKE: Sending EAP-EKE-Confirm/Response");
resp = eap_eke_build_msg(data, id,
data->sess.pnonce_len + data->sess.prf_len,
EAP_EKE_CONFIRM);
if (resp == NULL) {
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
prot_len = wpabuf_tailroom(resp);
if (eap_eke_prot(&data->sess, data->nonce_s, data->sess.nonce_len,
wpabuf_put(resp, 0), &prot_len) < 0) {
wpabuf_free(resp);
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
wpabuf_put(resp, prot_len);
auth = wpabuf_put(resp, data->sess.prf_len);
if (eap_eke_auth(&data->sess, "EAP-EKE peer", data->msgs, auth) < 0) {
wpabuf_free(resp);
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
wpa_hexdump(MSG_DEBUG, "EAP-EKE: Auth_P", auth, data->sess.prf_len);
if (eap_eke_derive_msk(&data->sess, data->serverid, data->serverid_len,
data->peerid, data->peerid_len,
data->nonce_s, data->nonce_p,
data->msk, data->emsk) < 0) {
wpa_printf(MSG_INFO, "EAP-EKE: Failed to derive MSK/EMSK");
wpabuf_free(resp);
return eap_eke_build_fail(data, ret, id,
EAP_EKE_FAIL_PRIVATE_INTERNAL_ERROR);
}
os_memset(data->dh_priv, 0, sizeof(data->dh_priv));
eap_eke_session_clean(&data->sess);
eap_eke_state(data, SUCCESS);
ret->methodState = METHOD_MAY_CONT;
ret->decision = DECISION_COND_SUCC;
ret->allowNotifications = FALSE;
return resp;
}
