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/*
* EAP peer method: LEAP
* Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "common.h"
#include "crypto/ms_funcs.h"
#include "crypto/crypto.h"
#include "crypto/random.h"
#include "eap_i.h"
#define LEAP_VERSION 1
#define LEAP_CHALLENGE_LEN 8
#define LEAP_RESPONSE_LEN 24
#define LEAP_KEY_LEN 16
struct eap_leap_data {
enum {
LEAP_WAIT_CHALLENGE,
LEAP_WAIT_SUCCESS,
LEAP_WAIT_RESPONSE,
LEAP_DONE
} state;
u8 peer_challenge[LEAP_CHALLENGE_LEN];
u8 peer_response[LEAP_RESPONSE_LEN];
u8 ap_challenge[LEAP_CHALLENGE_LEN];
u8 ap_response[LEAP_RESPONSE_LEN];
};
static void * eap_leap_init(struct eap_sm *sm)
{
struct eap_leap_data *data;
data = os_zalloc(sizeof(*data));
if (data == NULL)
return NULL;
data->state = LEAP_WAIT_CHALLENGE;
sm->leap_done = false;
return data;
}
static void eap_leap_deinit(struct eap_sm *sm, void *priv)
{
os_free(priv);
}
static struct wpabuf * eap_leap_process_request(struct eap_sm *sm, void *priv,
struct eap_method_ret *ret,
const struct wpabuf *reqData)
{
struct eap_leap_data *data = priv;
struct wpabuf *resp;
const u8 *pos, *challenge, *identity, *password;
u8 challenge_len, *rpos;
size_t identity_len, password_len, len;
int pwhash;
wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Request");
identity = eap_get_config_identity(sm, &identity_len);
password = eap_get_config_password2(sm, &password_len, &pwhash);
if (identity == NULL || password == NULL)
return NULL;
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_LEAP, reqData, &len);
if (pos == NULL || len < 3) {
wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Request frame");
ret->ignore = true;
return NULL;
}
if (*pos != LEAP_VERSION) {
wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version "
"%d", *pos);
ret->ignore = true;
return NULL;
}
pos++;
pos++; /* skip unused byte */
challenge_len = *pos++;
if (challenge_len != LEAP_CHALLENGE_LEN || challenge_len > len - 3) {
wpa_printf(MSG_INFO, "EAP-LEAP: Invalid challenge "
"(challenge_len=%d reqDataLen=%lu)",
challenge_len, (unsigned long) wpabuf_len(reqData));
ret->ignore = true;
return NULL;
}
challenge = pos;
os_memcpy(data->peer_challenge, challenge, LEAP_CHALLENGE_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge from AP",
challenge, LEAP_CHALLENGE_LEN);
wpa_printf(MSG_DEBUG, "EAP-LEAP: Generating Challenge Response");
resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP,
3 + LEAP_RESPONSE_LEN + identity_len,
EAP_CODE_RESPONSE, eap_get_id(reqData));
if (resp == NULL)
return NULL;
wpabuf_put_u8(resp, LEAP_VERSION);
wpabuf_put_u8(resp, 0); /* unused */
wpabuf_put_u8(resp, LEAP_RESPONSE_LEN);
rpos = wpabuf_put(resp, LEAP_RESPONSE_LEN);
if ((pwhash && challenge_response(challenge, password, rpos)) ||
(!pwhash &&
nt_challenge_response(challenge, password, password_len, rpos))) {
wpa_printf(MSG_DEBUG, "EAP-LEAP: Failed to derive response");
ret->ignore = true;
wpabuf_free(resp);
return NULL;
}
os_memcpy(data->peer_response, rpos, LEAP_RESPONSE_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Response",
rpos, LEAP_RESPONSE_LEN);
wpabuf_put_data(resp, identity, identity_len);
data->state = LEAP_WAIT_SUCCESS;
return resp;
}
static struct wpabuf * eap_leap_process_success(struct eap_sm *sm, void *priv,
struct eap_method_ret *ret,
const struct wpabuf *reqData)
{
struct eap_leap_data *data = priv;
struct wpabuf *resp;
u8 *pos;
const u8 *identity;
size_t identity_len;
wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Success");
identity = eap_get_config_identity(sm, &identity_len);
if (identity == NULL)
return NULL;
if (data->state != LEAP_WAIT_SUCCESS) {
wpa_printf(MSG_INFO, "EAP-LEAP: EAP-Success received in "
"unexpected state (%d) - ignored", data->state);
ret->ignore = true;
return NULL;
}
resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP,
3 + LEAP_CHALLENGE_LEN + identity_len,
EAP_CODE_REQUEST, eap_get_id(reqData));
if (resp == NULL)
return NULL;
wpabuf_put_u8(resp, LEAP_VERSION);
wpabuf_put_u8(resp, 0); /* unused */
wpabuf_put_u8(resp, LEAP_CHALLENGE_LEN);
pos = wpabuf_put(resp, LEAP_CHALLENGE_LEN);
if (random_get_bytes(pos, LEAP_CHALLENGE_LEN)) {
wpa_printf(MSG_WARNING, "EAP-LEAP: Failed to read random data "
"for challenge");
wpabuf_free(resp);
ret->ignore = true;
return NULL;
}
os_memcpy(data->ap_challenge, pos, LEAP_CHALLENGE_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge to AP/AS", pos,
LEAP_CHALLENGE_LEN);
wpabuf_put_data(resp, identity, identity_len);
data->state = LEAP_WAIT_RESPONSE;
return resp;
}
static struct wpabuf * eap_leap_process_response(struct eap_sm *sm, void *priv,
struct eap_method_ret *ret,
const struct wpabuf *reqData)
{
struct eap_leap_data *data = priv;
const u8 *pos, *password;
u8 response_len, pw_hash[16], pw_hash_hash[16],
expected[LEAP_RESPONSE_LEN];
size_t password_len, len;
int pwhash;
wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Response");
password = eap_get_config_password2(sm, &password_len, &pwhash);
if (password == NULL)
return NULL;
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_LEAP, reqData, &len);
if (pos == NULL || len < 3) {
wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Response frame");
ret->ignore = true;
return NULL;
}
if (*pos != LEAP_VERSION) {
wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version "
"%d", *pos);
ret->ignore = true;
return NULL;
}
pos++;
pos++; /* skip unused byte */
response_len = *pos++;
if (response_len != LEAP_RESPONSE_LEN || response_len > len - 3) {
wpa_printf(MSG_INFO, "EAP-LEAP: Invalid response "
"(response_len=%d reqDataLen=%lu)",
response_len, (unsigned long) wpabuf_len(reqData));
ret->ignore = true;
return NULL;
}
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Response from AP",
pos, LEAP_RESPONSE_LEN);
os_memcpy(data->ap_response, pos, LEAP_RESPONSE_LEN);
if (pwhash) {
if (hash_nt_password_hash(password, pw_hash_hash)) {
ret->ignore = true;
return NULL;
}
} else {
if (nt_password_hash(password, password_len, pw_hash) ||
hash_nt_password_hash(pw_hash, pw_hash_hash)) {
ret->ignore = true;
return NULL;
}
}
if (challenge_response(data->ap_challenge, pw_hash_hash, expected)) {
ret->ignore = true;
return NULL;
}
ret->methodState = METHOD_DONE;
ret->allowNotifications = false;
if (os_memcmp_const(pos, expected, LEAP_RESPONSE_LEN) != 0) {
wpa_printf(MSG_WARNING, "EAP-LEAP: AP sent an invalid "
"response - authentication failed");
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Expected response from AP",
expected, LEAP_RESPONSE_LEN);
ret->decision = DECISION_FAIL;
return NULL;
}
ret->decision = DECISION_UNCOND_SUCC;
/* LEAP is somewhat odd method since it sends EAP-Success in the middle
* of the authentication. Use special variable to transit EAP state
* machine to SUCCESS state. */
sm->leap_done = true;
data->state = LEAP_DONE;
/* No more authentication messages expected; AP will send EAPOL-Key
* frames if encryption is enabled. */
return NULL;
}
static struct wpabuf * eap_leap_process(struct eap_sm *sm, void *priv,
struct eap_method_ret *ret,
const struct wpabuf *reqData)
{
const struct eap_hdr *eap;
size_t password_len;
const u8 *password;
password = eap_get_config_password(sm, &password_len);
if (password == NULL) {
wpa_printf(MSG_INFO, "EAP-LEAP: Password not configured");
eap_sm_request_password(sm);
ret->ignore = true;
return NULL;
}
/*
* LEAP needs to be able to handle EAP-Success frame which does not
* include Type field. Consequently, eap_hdr_validate() cannot be used
* here. This validation will be done separately for EAP-Request and
* EAP-Response frames.
*/
eap = wpabuf_head(reqData);
if (wpabuf_len(reqData) < sizeof(*eap) ||
be_to_host16(eap->length) > wpabuf_len(reqData)) {
wpa_printf(MSG_INFO, "EAP-LEAP: Invalid frame");
ret->ignore = true;
return NULL;
}
ret->ignore = false;
ret->allowNotifications = true;
ret->methodState = METHOD_MAY_CONT;
ret->decision = DECISION_FAIL;
sm->leap_done = false;
switch (eap->code) {
case EAP_CODE_REQUEST:
return eap_leap_process_request(sm, priv, ret, reqData);
case EAP_CODE_SUCCESS:
return eap_leap_process_success(sm, priv, ret, reqData);
case EAP_CODE_RESPONSE:
return eap_leap_process_response(sm, priv, ret, reqData);
default:
wpa_printf(MSG_INFO, "EAP-LEAP: Unexpected EAP code (%d) - "
"ignored", eap->code);
ret->ignore = true;
return NULL;
}
}
static bool eap_leap_isKeyAvailable(struct eap_sm *sm, void *priv)
{
struct eap_leap_data *data = priv;
return data->state == LEAP_DONE;
}
static u8 * eap_leap_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
struct eap_leap_data *data = priv;
u8 *key, pw_hash_hash[16], pw_hash[16];
const u8 *addr[5], *password;
size_t elen[5], password_len;
int pwhash;
if (data->state != LEAP_DONE)
return NULL;
password = eap_get_config_password2(sm, &password_len, &pwhash);
if (password == NULL)
return NULL;
key = os_malloc(LEAP_KEY_LEN);
if (key == NULL)
return NULL;
if (pwhash) {
if (hash_nt_password_hash(password, pw_hash_hash)) {
os_free(key);
return NULL;
}
} else {
if (nt_password_hash(password, password_len, pw_hash) ||
hash_nt_password_hash(pw_hash, pw_hash_hash)) {
os_free(key);
return NULL;
}
}
wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: pw_hash_hash",
pw_hash_hash, 16);
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_challenge",
data->peer_challenge, LEAP_CHALLENGE_LEN);
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_response",
data->peer_response, LEAP_RESPONSE_LEN);
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_challenge",
data->ap_challenge, LEAP_CHALLENGE_LEN);
wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_response",
data->ap_response, LEAP_RESPONSE_LEN);
addr[0] = pw_hash_hash;
elen[0] = 16;
addr[1] = data->ap_challenge;
elen[1] = LEAP_CHALLENGE_LEN;
addr[2] = data->ap_response;
elen[2] = LEAP_RESPONSE_LEN;
addr[3] = data->peer_challenge;
elen[3] = LEAP_CHALLENGE_LEN;
addr[4] = data->peer_response;
elen[4] = LEAP_RESPONSE_LEN;
md5_vector(5, addr, elen, key);
wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: master key", key, LEAP_KEY_LEN);
*len = LEAP_KEY_LEN;
forced_memzero(pw_hash, sizeof(pw_hash));
forced_memzero(pw_hash_hash, sizeof(pw_hash_hash));
return key;
}
int eap_peer_leap_register(void)
{
struct eap_method *eap;
eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
EAP_VENDOR_IETF, EAP_TYPE_LEAP, "LEAP");
if (eap == NULL)
return -1;
eap->init = eap_leap_init;
eap->deinit = eap_leap_deinit;
eap->process = eap_leap_process;
eap->isKeyAvailable = eap_leap_isKeyAvailable;
eap->getKey = eap_leap_getKey;
return eap_peer_method_register(eap);
}