NetBSD/dist/hostapd/eap_ttls.c
2006-04-12 15:19:32 +00:00

1194 lines
31 KiB
C

/*
* hostapd / EAP-TTLS (draft-ietf-pppext-eap-ttls-05.txt)
* Copyright (c) 2004-2005, Jouni Malinen <jkmaline@cc.hut.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <netinet/in.h>
#include "hostapd.h"
#include "common.h"
#include "eap_i.h"
#include "eap_tls_common.h"
#include "ms_funcs.h"
#include "md5.h"
#include "crypto.h"
#include "tls.h"
#include "eap_ttls.h"
#define EAP_TTLS_VERSION 0
static void eap_ttls_reset(struct eap_sm *sm, void *priv);
struct eap_ttls_data {
struct eap_ssl_data ssl;
enum {
START, PHASE1, PHASE2_START, PHASE2_METHOD,
PHASE2_MSCHAPV2_RESP, SUCCESS, FAILURE
} state;
int ttls_version;
const struct eap_method *phase2_method;
void *phase2_priv;
int mschapv2_resp_ok;
u8 mschapv2_auth_response[20];
u8 mschapv2_ident;
};
static const char * eap_ttls_state_txt(int state)
{
switch (state) {
case START:
return "START";
case PHASE1:
return "PHASE1";
case PHASE2_START:
return "PHASE2_START";
case PHASE2_METHOD:
return "PHASE2_METHOD";
case PHASE2_MSCHAPV2_RESP:
return "PHASE2_MSCHAPV2_RESP";
case SUCCESS:
return "SUCCESS";
case FAILURE:
return "FAILURE";
default:
return "Unknown?!";
}
}
static void eap_ttls_state(struct eap_ttls_data *data, int state)
{
wpa_printf(MSG_DEBUG, "EAP-TTLS: %s -> %s",
eap_ttls_state_txt(data->state),
eap_ttls_state_txt(state));
data->state = state;
}
static u8 * eap_ttls_avp_hdr(u8 *avphdr, u32 avp_code, u32 vendor_id,
int mandatory, size_t len)
{
struct ttls_avp_vendor *avp;
u8 flags;
size_t hdrlen;
avp = (struct ttls_avp_vendor *) avphdr;
flags = mandatory ? AVP_FLAGS_MANDATORY : 0;
if (vendor_id) {
flags |= AVP_FLAGS_VENDOR;
hdrlen = sizeof(*avp);
avp->vendor_id = host_to_be32(vendor_id);
} else {
hdrlen = sizeof(struct ttls_avp);
}
avp->avp_code = host_to_be32(avp_code);
avp->avp_length = host_to_be32((flags << 24) | (hdrlen + len));
return avphdr + hdrlen;
}
static int eap_ttls_avp_encapsulate(u8 **resp, size_t *resp_len, u32 avp_code,
int mandatory)
{
u8 *avp, *pos;
avp = malloc(sizeof(struct ttls_avp) + *resp_len + 4);
if (avp == NULL) {
free(*resp);
*resp_len = 0;
return -1;
}
pos = eap_ttls_avp_hdr(avp, avp_code, 0, mandatory, *resp_len);
memcpy(pos, *resp, *resp_len);
pos += *resp_len;
AVP_PAD(avp, pos);
free(*resp);
*resp = avp;
*resp_len = pos - avp;
return 0;
}
struct eap_ttls_avp {
/* Note: eap is allocated memory; caller is responsible for freeing
* it. All the other pointers are pointing to the packet data, i.e.,
* they must not be freed separately. */
u8 *eap;
size_t eap_len;
u8 *user_name;
size_t user_name_len;
u8 *user_password;
size_t user_password_len;
u8 *chap_challenge;
size_t chap_challenge_len;
u8 *chap_password;
size_t chap_password_len;
u8 *mschap_challenge;
size_t mschap_challenge_len;
u8 *mschap_response;
size_t mschap_response_len;
u8 *mschap2_response;
size_t mschap2_response_len;
};
static int eap_ttls_avp_parse(u8 *buf, size_t len, struct eap_ttls_avp *parse)
{
struct ttls_avp *avp;
u8 *pos;
int left;
pos = buf;
left = len;
memset(parse, 0, sizeof(*parse));
while (left > 0) {
u32 avp_code, avp_length, vendor_id = 0;
u8 avp_flags, *dpos;
size_t pad, dlen;
avp = (struct ttls_avp *) pos;
avp_code = be_to_host32(avp->avp_code);
avp_length = be_to_host32(avp->avp_length);
avp_flags = (avp_length >> 24) & 0xff;
avp_length &= 0xffffff;
wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP: code=%d flags=0x%02x "
"length=%d", (int) avp_code, avp_flags,
(int) avp_length);
if (avp_length > left) {
wpa_printf(MSG_WARNING, "EAP-TTLS: AVP overflow "
"(len=%d, left=%d) - dropped",
(int) avp_length, left);
return -1;
}
dpos = (u8 *) (avp + 1);
dlen = avp_length - sizeof(*avp);
if (avp_flags & AVP_FLAGS_VENDOR) {
if (dlen < 4) {
wpa_printf(MSG_WARNING, "EAP-TTLS: vendor AVP "
"underflow");
return -1;
}
vendor_id = be_to_host32(* (u32 *) dpos);
wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP vendor_id %d",
(int) vendor_id);
dpos += 4;
dlen -= 4;
}
wpa_hexdump(MSG_DEBUG, "EAP-TTLS: AVP data", dpos, dlen);
if (vendor_id == 0 && avp_code == RADIUS_ATTR_EAP_MESSAGE) {
wpa_printf(MSG_DEBUG, "EAP-TTLS: AVP - EAP Message");
if (parse->eap == NULL) {
parse->eap = malloc(dlen);
if (parse->eap == NULL) {
wpa_printf(MSG_WARNING, "EAP-TTLS: "
"failed to allocate memory "
"for Phase 2 EAP data");
return -1;
}
memcpy(parse->eap, dpos, dlen);
parse->eap_len = dlen;
} else {
u8 *neweap = realloc(parse->eap,
parse->eap_len + dlen);
if (neweap == NULL) {
wpa_printf(MSG_WARNING, "EAP-TTLS: "
"failed to allocate memory "
"for Phase 2 EAP data");
free(parse->eap);
parse->eap = NULL;
return -1;
}
memcpy(neweap + parse->eap_len, dpos, dlen);
parse->eap = neweap;
parse->eap_len += dlen;
}
} else if (vendor_id == 0 &&
avp_code == RADIUS_ATTR_USER_NAME) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-TTLS: User-Name",
dpos, dlen);
parse->user_name = dpos;
parse->user_name_len = dlen;
} else if (vendor_id == 0 &&
avp_code == RADIUS_ATTR_USER_PASSWORD) {
u8 *password = dpos;
size_t password_len = dlen;
while (password_len > 0 &&
password[password_len - 1] == '\0') {
password_len--;
}
wpa_hexdump_ascii_key(MSG_DEBUG, "EAP-TTLS: "
"User-Password (PAP)",
password, password_len);
parse->user_password = password;
parse->user_password_len = password_len;
} else if (vendor_id == 0 &&
avp_code == RADIUS_ATTR_CHAP_CHALLENGE) {
wpa_hexdump(MSG_DEBUG,
"EAP-TTLS: CHAP-Challenge (CHAP)",
dpos, dlen);
parse->chap_challenge = dpos;
parse->chap_challenge_len = dlen;
} else if (vendor_id == 0 &&
avp_code == RADIUS_ATTR_CHAP_PASSWORD) {
wpa_hexdump(MSG_DEBUG,
"EAP-TTLS: CHAP-Password (CHAP)",
dpos, dlen);
parse->chap_password = dpos;
parse->chap_password_len = dlen;
} else if (vendor_id == RADIUS_VENDOR_ID_MICROSOFT &&
avp_code == RADIUS_ATTR_MS_CHAP_CHALLENGE) {
wpa_hexdump(MSG_DEBUG,
"EAP-TTLS: MS-CHAP-Challenge",
dpos, dlen);
parse->mschap_challenge = dpos;
parse->mschap_challenge_len = dlen;
} else if (vendor_id == RADIUS_VENDOR_ID_MICROSOFT &&
avp_code == RADIUS_ATTR_MS_CHAP_RESPONSE) {
wpa_hexdump(MSG_DEBUG,
"EAP-TTLS: MS-CHAP-Response (MSCHAP)",
dpos, dlen);
parse->mschap_response = dpos;
parse->mschap_response_len = dlen;
} else if (vendor_id == RADIUS_VENDOR_ID_MICROSOFT &&
avp_code == RADIUS_ATTR_MS_CHAP2_RESPONSE) {
wpa_hexdump(MSG_DEBUG,
"EAP-TTLS: MS-CHAP2-Response (MSCHAPV2)",
dpos, dlen);
parse->mschap2_response = dpos;
parse->mschap2_response_len = dlen;
} else if (avp_flags & AVP_FLAGS_MANDATORY) {
wpa_printf(MSG_WARNING, "EAP-TTLS: Unsupported "
"mandatory AVP code %d vendor_id %d - "
"dropped", (int) avp_code, (int) vendor_id);
return -1;
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS: Ignoring unsupported "
"AVP code %d vendor_id %d",
(int) avp_code, (int) vendor_id);
}
pad = (4 - (avp_length & 3)) & 3;
pos += avp_length + pad;
left -= avp_length + pad;
}
return 0;
}
static void * eap_ttls_init(struct eap_sm *sm)
{
struct eap_ttls_data *data;
data = malloc(sizeof(*data));
if (data == NULL)
return data;
memset(data, 0, sizeof(*data));
data->ttls_version = EAP_TTLS_VERSION;
data->state = START;
if (eap_tls_ssl_init(sm, &data->ssl, 0)) {
wpa_printf(MSG_INFO, "EAP-TTLS: Failed to initialize SSL.");
eap_ttls_reset(sm, data);
return NULL;
}
return data;
}
static void eap_ttls_reset(struct eap_sm *sm, void *priv)
{
struct eap_ttls_data *data = priv;
if (data == NULL)
return;
if (data->phase2_priv && data->phase2_method)
data->phase2_method->reset(sm, data->phase2_priv);
eap_tls_ssl_deinit(sm, &data->ssl);
free(data);
}
static u8 * eap_ttls_build_start(struct eap_sm *sm, struct eap_ttls_data *data,
int id, size_t *reqDataLen)
{
struct eap_hdr *req;
u8 *pos;
*reqDataLen = sizeof(*req) + 2;
req = malloc(*reqDataLen);
if (req == NULL) {
wpa_printf(MSG_ERROR, "EAP-TTLS: Failed to allocate memory for"
" request");
eap_ttls_state(data, FAILURE);
return NULL;
}
req->code = EAP_CODE_REQUEST;
req->identifier = id;
req->length = htons(*reqDataLen);
pos = (u8 *) (req + 1);
*pos++ = EAP_TYPE_TTLS;
*pos = EAP_TLS_FLAGS_START | data->ttls_version;
eap_ttls_state(data, PHASE1);
return (u8 *) req;
}
static u8 * eap_ttls_build_req(struct eap_sm *sm, struct eap_ttls_data *data,
int id, size_t *reqDataLen)
{
int res;
u8 *req;
res = eap_tls_buildReq_helper(sm, &data->ssl, EAP_TYPE_TTLS,
data->ttls_version, id, &req,
reqDataLen);
if (tls_connection_established(sm->ssl_ctx, data->ssl.conn)) {
wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase1 done, starting "
"Phase2");
eap_ttls_state(data, PHASE2_START);
}
if (res == 1)
return eap_tls_build_ack(reqDataLen, id, EAP_TYPE_TTLS,
data->ttls_version);
return req;
}
static u8 * eap_ttls_encrypt(struct eap_sm *sm, struct eap_ttls_data *data,
int id, u8 *plain, size_t plain_len,
size_t *out_len)
{
int res;
u8 *pos;
struct eap_hdr *req;
/* TODO: add support for fragmentation, if needed. This will need to
* add TLS Message Length field, if the frame is fragmented. */
req = malloc(sizeof(struct eap_hdr) + 2 + data->ssl.tls_out_limit);
if (req == NULL)
return NULL;
req->code = EAP_CODE_REQUEST;
req->identifier = id;
pos = (u8 *) (req + 1);
*pos++ = EAP_TYPE_TTLS;
*pos++ = data->ttls_version;
res = tls_connection_encrypt(sm->ssl_ctx, data->ssl.conn,
plain, plain_len,
pos, data->ssl.tls_out_limit);
if (res < 0) {
wpa_printf(MSG_INFO, "EAP-TTLS: Failed to encrypt Phase 2 "
"data");
free(req);
return NULL;
}
*out_len = sizeof(struct eap_hdr) + 2 + res;
req->length = host_to_be16(*out_len);
return (u8 *) req;
}
static u8 * eap_ttls_build_phase2_eap_req(struct eap_sm *sm,
struct eap_ttls_data *data,
int id, size_t *reqDataLen)
{
u8 *req, *encr_req;
size_t req_len;
req = data->phase2_method->buildReq(sm, data->phase2_priv, id,
&req_len);
if (req == NULL)
return NULL;
wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS/EAP: Encapsulate Phase 2 data",
req, req_len);
if (eap_ttls_avp_encapsulate(&req, &req_len, RADIUS_ATTR_EAP_MESSAGE,
1) < 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: Failed to encapsulate "
"packet");
return NULL;
}
wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS/EAP: Encrypt encapsulated Phase "
"2 data", req, req_len);
encr_req = eap_ttls_encrypt(sm, data, id, req, req_len, reqDataLen);
free(req);
return encr_req;
}
static u8 * eap_ttls_build_phase2_mschapv2(struct eap_sm *sm,
struct eap_ttls_data *data,
int id, size_t *reqDataLen)
{
u8 *req, *encr_req, *pos, *end;
size_t req_len;
int i;
pos = req = malloc(100);
if (req == NULL)
return NULL;
end = req + 200;
if (data->mschapv2_resp_ok) {
pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_MS_CHAP2_SUCCESS,
RADIUS_VENDOR_ID_MICROSOFT, 1, 43);
*pos++ = data->mschapv2_ident;
pos += snprintf((char *) pos, end - pos, "S=");
for (i = 0; i < sizeof(data->mschapv2_auth_response); i++) {
pos += snprintf((char *) pos, end - pos, "%02X",
data->mschapv2_auth_response[i]);
}
} else {
pos = eap_ttls_avp_hdr(pos, RADIUS_ATTR_MS_CHAP_ERROR,
RADIUS_VENDOR_ID_MICROSOFT, 1, 6);
memcpy(pos, "Failed", 6);
pos += 6;
AVP_PAD(req, pos);
}
req_len = pos - req;
wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Encrypting Phase 2 "
"data", req, req_len);
encr_req = eap_ttls_encrypt(sm, data, id, req, req_len, reqDataLen);
free(req);
return encr_req;
}
static u8 * eap_ttls_buildReq(struct eap_sm *sm, void *priv, int id,
size_t *reqDataLen)
{
struct eap_ttls_data *data = priv;
switch (data->state) {
case START:
return eap_ttls_build_start(sm, data, id, reqDataLen);
case PHASE1:
return eap_ttls_build_req(sm, data, id, reqDataLen);
case PHASE2_METHOD:
return eap_ttls_build_phase2_eap_req(sm, data, id, reqDataLen);
case PHASE2_MSCHAPV2_RESP:
return eap_ttls_build_phase2_mschapv2(sm, data, id,
reqDataLen);
default:
wpa_printf(MSG_DEBUG, "EAP-TTLS: %s - unexpected state %d",
__func__, data->state);
return NULL;
}
}
static Boolean eap_ttls_check(struct eap_sm *sm, void *priv,
u8 *respData, size_t respDataLen)
{
struct eap_hdr *resp;
u8 *pos;
size_t len;
resp = (struct eap_hdr *) respData;
pos = (u8 *) (resp + 1);
if (respDataLen < sizeof(*resp) + 2 || *pos != EAP_TYPE_TTLS ||
(len = ntohs(resp->length)) > respDataLen) {
wpa_printf(MSG_INFO, "EAP-TTLS: Invalid frame");
return TRUE;
}
return FALSE;
}
static void eap_ttls_process_phase2_pap(struct eap_sm *sm,
struct eap_ttls_data *data,
const u8 *user_password,
size_t user_password_len)
{
/* TODO: add support for verifying that the user entry accepts
* EAP-TTLS/PAP. */
if (!sm->user || !sm->user->password) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/PAP: No user password "
"configured");
eap_ttls_state(data, FAILURE);
return;
}
if (sm->user->password_len != user_password_len ||
memcmp(sm->user->password, user_password, user_password_len) != 0)
{
wpa_printf(MSG_DEBUG, "EAP-TTLS/PAP: Invalid user password");
eap_ttls_state(data, FAILURE);
return;
}
wpa_printf(MSG_DEBUG, "EAP-TTLS/PAP: Correct user password");
eap_ttls_state(data, SUCCESS);
}
static void eap_ttls_process_phase2_chap(struct eap_sm *sm,
struct eap_ttls_data *data,
const u8 *challenge,
size_t challenge_len,
const u8 *password,
size_t password_len)
{
u8 *chal, hash[MD5_MAC_LEN];
const u8 *addr[3];
size_t len[3];
if (challenge == NULL || password == NULL ||
challenge_len != EAP_TTLS_CHAP_CHALLENGE_LEN ||
password_len != 1 + EAP_TTLS_CHAP_PASSWORD_LEN) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Invalid CHAP attributes "
"(challenge len %lu password len %lu)",
(unsigned long) challenge_len,
(unsigned long) password_len);
eap_ttls_state(data, FAILURE);
return;
}
/* TODO: add support for verifying that the user entry accepts
* EAP-TTLS/CHAP. */
if (!sm->user || !sm->user->password) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: No user password "
"configured");
eap_ttls_state(data, FAILURE);
return;
}
chal = eap_tls_derive_key(sm, &data->ssl, "ttls challenge",
EAP_TTLS_CHAP_CHALLENGE_LEN + 1);
if (chal == NULL) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Failed to generate "
"challenge from TLS data");
eap_ttls_state(data, FAILURE);
return;
}
if (memcmp(challenge, chal, EAP_TTLS_CHAP_CHALLENGE_LEN) != 0 ||
password[0] != chal[EAP_TTLS_CHAP_CHALLENGE_LEN]) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Challenge mismatch");
free(chal);
eap_ttls_state(data, FAILURE);
return;
}
free(chal);
/* MD5(Ident + Password + Challenge) */
addr[0] = password;
len[0] = 1;
addr[1] = sm->user->password;
len[1] = sm->user->password_len;
addr[2] = challenge;
len[2] = challenge_len;
md5_vector(3, addr, len, hash);
if (memcmp(hash, password + 1, EAP_TTLS_CHAP_PASSWORD_LEN) == 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Correct user password");
eap_ttls_state(data, SUCCESS);
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS/CHAP: Invalid user password");
eap_ttls_state(data, FAILURE);
}
}
static void eap_ttls_process_phase2_mschap(struct eap_sm *sm,
struct eap_ttls_data *data,
u8 *challenge, size_t challenge_len,
u8 *response, size_t response_len)
{
u8 *chal, nt_response[24];
if (challenge == NULL || response == NULL ||
challenge_len != EAP_TTLS_MSCHAP_CHALLENGE_LEN ||
response_len != EAP_TTLS_MSCHAP_RESPONSE_LEN) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Invalid MS-CHAP "
"attributes (challenge len %lu response len %lu)",
(unsigned long) challenge_len,
(unsigned long) response_len);
eap_ttls_state(data, FAILURE);
return;
}
/* TODO: add support for verifying that the user entry accepts
* EAP-TTLS/MSCHAP. */
if (!sm->user || !sm->user->password) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: No user password "
"configured");
eap_ttls_state(data, FAILURE);
return;
}
chal = eap_tls_derive_key(sm, &data->ssl, "ttls challenge",
EAP_TTLS_MSCHAP_CHALLENGE_LEN + 1);
if (chal == NULL) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Failed to generate "
"challenge from TLS data");
eap_ttls_state(data, FAILURE);
return;
}
if (memcmp(challenge, chal, EAP_TTLS_MSCHAP_CHALLENGE_LEN) != 0 ||
response[0] != chal[EAP_TTLS_MSCHAP_CHALLENGE_LEN]) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Challenge mismatch");
free(chal);
eap_ttls_state(data, FAILURE);
return;
}
free(chal);
nt_challenge_response(challenge, sm->user->password,
sm->user->password_len, nt_response);
if (memcmp(nt_response, response + 2 + 24, 24) == 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Correct response");
eap_ttls_state(data, SUCCESS);
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAP: Invalid NT-Response");
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAP: Received",
response + 2 + 24, 24);
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAP: Expected",
nt_response, 24);
eap_ttls_state(data, FAILURE);
}
}
static void eap_ttls_process_phase2_mschapv2(struct eap_sm *sm,
struct eap_ttls_data *data,
u8 *challenge,
size_t challenge_len,
u8 *response, size_t response_len)
{
u8 *chal, *username, nt_response[24], *pos, *rx_resp, *peer_challenge,
*auth_challenge;
size_t username_len;
int i;
if (challenge == NULL || response == NULL ||
challenge_len != EAP_TTLS_MSCHAPV2_CHALLENGE_LEN ||
response_len != EAP_TTLS_MSCHAPV2_RESPONSE_LEN) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Invalid MS-CHAP2 "
"attributes (challenge len %lu response len %lu)",
(unsigned long) challenge_len,
(unsigned long) response_len);
eap_ttls_state(data, FAILURE);
return;
}
/* TODO: add support for verifying that the user entry accepts
* EAP-TTLS/MSCHAPV2. */
if (!sm->user || !sm->user->password) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: No user password "
"configured");
eap_ttls_state(data, FAILURE);
return;
}
/* MSCHAPv2 does not include optional domain name in the
* challenge-response calculation, so remove domain prefix
* (if present). */
username = sm->identity;
username_len = sm->identity_len;
pos = username;
for (i = 0; i < username_len; i++) {
if (username[i] == '\\') {
username_len -= i + 1;
username += i + 1;
break;
}
}
chal = eap_tls_derive_key(sm, &data->ssl, "ttls challenge",
EAP_TTLS_MSCHAPV2_CHALLENGE_LEN + 1);
if (chal == NULL) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Failed to generate "
"challenge from TLS data");
eap_ttls_state(data, FAILURE);
return;
}
if (memcmp(challenge, chal, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN) != 0 ||
response[0] != chal[EAP_TTLS_MSCHAPV2_CHALLENGE_LEN]) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Challenge mismatch");
free(chal);
eap_ttls_state(data, FAILURE);
return;
}
free(chal);
auth_challenge = challenge;
peer_challenge = response + 2;
wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-TTLS/MSCHAPV2: User",
username, username_len);
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAPV2: auth_challenge",
auth_challenge, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN);
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAPV2: peer_challenge",
peer_challenge, EAP_TTLS_MSCHAPV2_CHALLENGE_LEN);
generate_nt_response(auth_challenge, peer_challenge,
username, username_len,
sm->user->password, sm->user->password_len,
nt_response);
rx_resp = response + 2 + EAP_TTLS_MSCHAPV2_CHALLENGE_LEN + 8;
if (memcmp(nt_response, rx_resp, 24) == 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Correct "
"NT-Response");
data->mschapv2_resp_ok = 1;
generate_authenticator_response(sm->user->password,
sm->user->password_len,
peer_challenge,
auth_challenge,
username, username_len,
nt_response,
data->mschapv2_auth_response);
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Invalid "
"NT-Response");
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAPV2: Received",
rx_resp, 24);
wpa_hexdump(MSG_MSGDUMP, "EAP-TTLS/MSCHAPV2: Expected",
nt_response, 24);
data->mschapv2_resp_ok = 0;
}
eap_ttls_state(data, PHASE2_MSCHAPV2_RESP);
data->mschapv2_ident = response[0];
}
static int eap_ttls_phase2_eap_init(struct eap_sm *sm,
struct eap_ttls_data *data, u8 eap_type)
{
if (data->phase2_priv && data->phase2_method) {
data->phase2_method->reset(sm, data->phase2_priv);
data->phase2_method = NULL;
data->phase2_priv = NULL;
}
data->phase2_method = eap_sm_get_eap_methods(eap_type);
if (!data->phase2_method)
return -1;
sm->init_phase2 = 1;
data->phase2_priv = data->phase2_method->init(sm);
sm->init_phase2 = 0;
return 0;
}
static void eap_ttls_process_phase2_eap_response(struct eap_sm *sm,
struct eap_ttls_data *data,
u8 *in_data, size_t in_len)
{
u8 next_type = EAP_TYPE_NONE;
struct eap_hdr *hdr;
u8 *pos;
size_t left;
if (data->phase2_priv == NULL) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: %s - Phase2 not "
"initialized?!", __func__);
return;
}
hdr = (struct eap_hdr *) in_data;
pos = (u8 *) (hdr + 1);
left = in_len - sizeof(*hdr);
if (in_len > sizeof(*hdr) && *pos == EAP_TYPE_NAK) {
wpa_hexdump(MSG_DEBUG, "EAP-TTLS/EAP: Phase2 type Nak'ed; "
"allowed types", pos + 1, left - 1);
eap_sm_process_nak(sm, pos + 1, left - 1);
if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS &&
sm->user->methods[sm->user_eap_method_index] !=
EAP_TYPE_NONE) {
next_type =
sm->user->methods[sm->user_eap_method_index++];
wpa_printf(MSG_DEBUG, "EAP-TTLS: try EAP type %d",
next_type);
eap_ttls_phase2_eap_init(sm, data, next_type);
} else {
eap_ttls_state(data, FAILURE);
}
return;
}
if (data->phase2_method->check(sm, data->phase2_priv, in_data,
in_len)) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: Phase2 check() asked to "
"ignore the packet");
return;
}
data->phase2_method->process(sm, data->phase2_priv, in_data, in_len);
if (!data->phase2_method->isDone(sm, data->phase2_priv))
return;
if (!data->phase2_method->isSuccess(sm, data->phase2_priv)) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: Phase2 method failed");
eap_ttls_state(data, FAILURE);
return;
}
switch (data->state) {
case PHASE2_START:
if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP_TTLS: Phase2 "
"Identity not found in the user "
"database",
sm->identity, sm->identity_len);
eap_ttls_state(data, FAILURE);
break;
}
eap_ttls_state(data, PHASE2_METHOD);
next_type = sm->user->methods[0];
sm->user_eap_method_index = 1;
wpa_printf(MSG_DEBUG, "EAP-TTLS: try EAP type %d", next_type);
break;
case PHASE2_METHOD:
eap_ttls_state(data, SUCCESS);
break;
case FAILURE:
break;
default:
wpa_printf(MSG_DEBUG, "EAP-TTLS: %s - unexpected state %d",
__func__, data->state);
break;
}
eap_ttls_phase2_eap_init(sm, data, next_type);
}
static void eap_ttls_process_phase2_eap(struct eap_sm *sm,
struct eap_ttls_data *data,
const u8 *eap, size_t eap_len)
{
struct eap_hdr *hdr;
size_t len;
if (data->state == PHASE2_START) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: initializing Phase 2");
if (eap_ttls_phase2_eap_init(sm, data, EAP_TYPE_IDENTITY) < 0)
{
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: failed to "
"initialize EAP-Identity");
return;
}
}
if (eap_len < sizeof(*hdr)) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: too short Phase 2 EAP "
"packet (len=%lu)", (unsigned long) eap_len);
return;
}
hdr = (struct eap_hdr *) eap;
len = be_to_host16(hdr->length);
wpa_printf(MSG_DEBUG, "EAP-TTLS/EAP: received Phase 2 EAP: code=%d "
"identifier=%d length=%lu", hdr->code, hdr->identifier,
(unsigned long) len);
if (len > eap_len) {
wpa_printf(MSG_INFO, "EAP-TTLS/EAP: Length mismatch in Phase 2"
" EAP frame (hdr len=%lu, data len in AVP=%lu)",
(unsigned long) len, (unsigned long) eap_len);
return;
}
switch (hdr->code) {
case EAP_CODE_RESPONSE:
eap_ttls_process_phase2_eap_response(sm, data, (u8 *) hdr,
len);
break;
default:
wpa_printf(MSG_INFO, "EAP-TTLS/EAP: Unexpected code=%d in "
"Phase 2 EAP header", hdr->code);
break;
}
}
static void eap_ttls_process_phase2(struct eap_sm *sm,
struct eap_ttls_data *data,
struct eap_hdr *resp,
u8 *in_data, size_t in_len)
{
u8 *in_decrypted;
int buf_len, len_decrypted, res;
struct eap_ttls_avp parse;
wpa_printf(MSG_DEBUG, "EAP-TTLS: received %lu bytes encrypted data for"
" Phase 2", (unsigned long) in_len);
res = eap_tls_data_reassemble(sm, &data->ssl, &in_data, &in_len);
if (res < 0 || res == 1)
return;
buf_len = in_len;
if (data->ssl.tls_in_total > buf_len)
buf_len = data->ssl.tls_in_total;
in_decrypted = malloc(buf_len);
if (in_decrypted == NULL) {
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
wpa_printf(MSG_WARNING, "EAP-TTLS: failed to allocate memory "
"for decryption");
return;
}
len_decrypted = tls_connection_decrypt(sm->ssl_ctx, data->ssl.conn,
in_data, in_len,
in_decrypted, buf_len);
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
if (len_decrypted < 0) {
wpa_printf(MSG_INFO, "EAP-TTLS: Failed to decrypt Phase 2 "
"data");
free(in_decrypted);
eap_ttls_state(data, FAILURE);
return;
}
wpa_hexdump_key(MSG_DEBUG, "EAP-TTLS: Decrypted Phase 2 EAP",
in_decrypted, len_decrypted);
if (eap_ttls_avp_parse(in_decrypted, len_decrypted, &parse) < 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS: Failed to parse AVPs");
free(in_decrypted);
eap_ttls_state(data, FAILURE);
return;
}
if (parse.user_name) {
free(sm->identity);
sm->identity = malloc(parse.user_name_len);
if (sm->identity) {
memcpy(sm->identity, parse.user_name,
parse.user_name_len);
sm->identity_len = parse.user_name_len;
}
if (eap_user_get(sm, parse.user_name, parse.user_name_len, 1)
!= 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS: Phase2 Identity not "
"found in the user database");
eap_ttls_state(data, FAILURE);
goto done;
}
}
if (parse.eap) {
eap_ttls_process_phase2_eap(sm, data, parse.eap,
parse.eap_len);
} else if (parse.user_password) {
eap_ttls_process_phase2_pap(sm, data, parse.user_password,
parse.user_password_len);
} else if (parse.chap_password) {
eap_ttls_process_phase2_chap(sm, data,
parse.chap_challenge,
parse.chap_challenge_len,
parse.chap_password,
parse.chap_password_len);
} else if (parse.mschap_response) {
eap_ttls_process_phase2_mschap(sm, data,
parse.mschap_challenge,
parse.mschap_challenge_len,
parse.mschap_response,
parse.mschap_response_len);
} else if (parse.mschap2_response) {
eap_ttls_process_phase2_mschapv2(sm, data,
parse.mschap_challenge,
parse.mschap_challenge_len,
parse.mschap2_response,
parse.mschap2_response_len);
}
done:
free(in_decrypted);
free(parse.eap);
}
static void eap_ttls_process(struct eap_sm *sm, void *priv,
u8 *respData, size_t respDataLen)
{
struct eap_ttls_data *data = priv;
struct eap_hdr *resp;
u8 *pos, flags;
int left;
unsigned int tls_msg_len;
int peer_version;
resp = (struct eap_hdr *) respData;
pos = (u8 *) (resp + 1);
pos++;
flags = *pos++;
left = htons(resp->length) - sizeof(struct eap_hdr) - 2;
wpa_printf(MSG_DEBUG, "EAP-TTLS: Received packet(len=%lu) - "
"Flags 0x%02x", (unsigned long) respDataLen, flags);
peer_version = flags & EAP_PEAP_VERSION_MASK;
if (peer_version < data->ttls_version) {
wpa_printf(MSG_DEBUG, "EAP-TTLS: peer ver=%d, own ver=%d; "
"use version %d",
peer_version, data->ttls_version, peer_version);
data->ttls_version = peer_version;
}
if (flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
if (left < 4) {
wpa_printf(MSG_INFO, "EAP-TTLS: Short frame with TLS "
"length");
eap_ttls_state(data, FAILURE);
return;
}
tls_msg_len = (pos[0] << 24) | (pos[1] << 16) | (pos[2] << 8) |
pos[3];
wpa_printf(MSG_DEBUG, "EAP-TTLS: TLS Message Length: %d",
tls_msg_len);
if (data->ssl.tls_in_left == 0) {
data->ssl.tls_in_total = tls_msg_len;
data->ssl.tls_in_left = tls_msg_len;
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
}
pos += 4;
left -= 4;
}
switch (data->state) {
case PHASE1:
if (eap_tls_process_helper(sm, &data->ssl, pos, left) < 0) {
wpa_printf(MSG_INFO, "EAP-TTLS: TLS processing "
"failed");
eap_ttls_state(data, FAILURE);
}
break;
case PHASE2_START:
case PHASE2_METHOD:
eap_ttls_process_phase2(sm, data, resp, pos, left);
break;
case PHASE2_MSCHAPV2_RESP:
if (data->mschapv2_resp_ok && left == 0) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Peer "
"acknowledged response");
eap_ttls_state(data, SUCCESS);
} else if (!data->mschapv2_resp_ok) {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Peer "
"acknowledged error");
eap_ttls_state(data, FAILURE);
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS/MSCHAPV2: Unexpected "
"frame from peer (payload len %d, expected "
"empty frame)", left);
eap_ttls_state(data, FAILURE);
}
break;
default:
wpa_printf(MSG_DEBUG, "EAP-TTLS: Unexpected state %d in %s",
data->state, __func__);
break;
}
if (tls_connection_get_write_alerts(sm->ssl_ctx, data->ssl.conn) > 1) {
wpa_printf(MSG_INFO, "EAP-TTLS: Locally detected fatal error "
"in TLS processing");
eap_ttls_state(data, FAILURE);
}
}
static Boolean eap_ttls_isDone(struct eap_sm *sm, void *priv)
{
struct eap_ttls_data *data = priv;
return data->state == SUCCESS || data->state == FAILURE;
}
static u8 * eap_ttls_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
struct eap_ttls_data *data = priv;
u8 *eapKeyData;
if (data->state != SUCCESS)
return NULL;
eapKeyData = eap_tls_derive_key(sm, &data->ssl,
"ttls keying material",
EAP_TLS_KEY_LEN);
if (eapKeyData) {
*len = EAP_TLS_KEY_LEN;
wpa_hexdump(MSG_DEBUG, "EAP-TTLS: Derived key",
eapKeyData, EAP_TLS_KEY_LEN);
} else {
wpa_printf(MSG_DEBUG, "EAP-TTLS: Failed to derive key");
}
return eapKeyData;
}
static Boolean eap_ttls_isSuccess(struct eap_sm *sm, void *priv)
{
struct eap_ttls_data *data = priv;
return data->state == SUCCESS;
}
const struct eap_method eap_method_ttls =
{
.method = EAP_TYPE_TTLS,
.name = "TTLS",
.init = eap_ttls_init,
.reset = eap_ttls_reset,
.buildReq = eap_ttls_buildReq,
.check = eap_ttls_check,
.process = eap_ttls_process,
.isDone = eap_ttls_isDone,
.getKey = eap_ttls_getKey,
.isSuccess = eap_ttls_isSuccess,
};