www.project-moonshot.org Git - mech_eap.orig/blob - libeap/src/eap_peer/eap_leap.c

   1 /*
   2  * EAP peer method: LEAP
   3  * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "crypto/ms_funcs.h"
  19 #include "crypto/crypto.h"
  20 #include "eap_i.h"
  21
  22 #define LEAP_VERSION 1
  23 #define LEAP_CHALLENGE_LEN 8
  24 #define LEAP_RESPONSE_LEN 24
  25 #define LEAP_KEY_LEN 16
  26
  27
  28 struct eap_leap_data {
  29         enum {
  30                 LEAP_WAIT_CHALLENGE,
  31                 LEAP_WAIT_SUCCESS,
  32                 LEAP_WAIT_RESPONSE,
  33                 LEAP_DONE
  34         } state;
  35
  36         u8 peer_challenge[LEAP_CHALLENGE_LEN];
  37         u8 peer_response[LEAP_RESPONSE_LEN];
  38
  39         u8 ap_challenge[LEAP_CHALLENGE_LEN];
  40         u8 ap_response[LEAP_RESPONSE_LEN];
  41 };
  42
  43
  44 static void * eap_leap_init(struct eap_sm *sm)
  45 {
  46         struct eap_leap_data *data;
  47
  48         data = os_zalloc(sizeof(*data));
  49         if (data == NULL)
  50                 return NULL;
  51         data->state = LEAP_WAIT_CHALLENGE;
  52
  53         sm->leap_done = FALSE;
  54         return data;
  55 }
  56
  57
  58 static void eap_leap_deinit(struct eap_sm *sm, void *priv)
  59 {
  60         os_free(priv);
  61 }
  62
  63
  64 static struct wpabuf * eap_leap_process_request(struct eap_sm *sm, void *priv,
  65                                                 struct eap_method_ret *ret,
  66                                                 const struct wpabuf *reqData)
  67 {
  68         struct eap_leap_data *data = priv;
  69         struct wpabuf *resp;
  70         const u8 *pos, *challenge, *identity, *password;
  71         u8 challenge_len, *rpos;
  72         size_t identity_len, password_len, len;
  73         int pwhash;
  74
  75         wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Request");
  76
  77         identity = eap_get_config_identity(sm, &identity_len);
  78         password = eap_get_config_password2(sm, &password_len, &pwhash);
  79         if (identity == NULL || password == NULL)
  80                 return NULL;
  81
  82         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_LEAP, reqData, &len);
  83         if (pos == NULL || len < 3) {
  84                 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Request frame");
  85                 ret->ignore = TRUE;
  86                 return NULL;
  87         }
  88
  89         if (*pos != LEAP_VERSION) {
  90                 wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version "
  91                            "%d", *pos);
  92                 ret->ignore = TRUE;
  93                 return NULL;
  94         }
  95         pos++;
  96
  97         pos++; /* skip unused byte */
  98
  99         challenge_len = *pos++;
 100         if (challenge_len != LEAP_CHALLENGE_LEN || challenge_len > len - 3) {
 101                 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid challenge "
 102                            "(challenge_len=%d reqDataLen=%lu)",
 103                            challenge_len, (unsigned long) wpabuf_len(reqData));
 104                 ret->ignore = TRUE;
 105                 return NULL;
 106         }
 107         challenge = pos;
 108         os_memcpy(data->peer_challenge, challenge, LEAP_CHALLENGE_LEN);
 109         wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge from AP",
 110                     challenge, LEAP_CHALLENGE_LEN);
 111
 112         wpa_printf(MSG_DEBUG, "EAP-LEAP: Generating Challenge Response");
 113
 114         resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP,
 115                              3 + LEAP_RESPONSE_LEN + identity_len,
 116                              EAP_CODE_RESPONSE, eap_get_id(reqData));
 117         if (resp == NULL)
 118                 return NULL;
 119         wpabuf_put_u8(resp, LEAP_VERSION);
 120         wpabuf_put_u8(resp, 0); /* unused */
 121         wpabuf_put_u8(resp, LEAP_RESPONSE_LEN);
 122         rpos = wpabuf_put(resp, LEAP_RESPONSE_LEN);
 123         if (pwhash)
 124                 challenge_response(challenge, password, rpos);
 125         else
 126                 nt_challenge_response(challenge, password, password_len, rpos);
 127         os_memcpy(data->peer_response, rpos, LEAP_RESPONSE_LEN);
 128         wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Response",
 129                     rpos, LEAP_RESPONSE_LEN);
 130         wpabuf_put_data(resp, identity, identity_len);
 131
 132         data->state = LEAP_WAIT_SUCCESS;
 133
 134         return resp;
 135 }
 136
 137
 138 static struct wpabuf * eap_leap_process_success(struct eap_sm *sm, void *priv,
 139                                                 struct eap_method_ret *ret,
 140                                                 const struct wpabuf *reqData)
 141 {
 142         struct eap_leap_data *data = priv;
 143         struct wpabuf *resp;
 144         u8 *pos;
 145         const u8 *identity;
 146         size_t identity_len;
 147
 148         wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Success");
 149
 150         identity = eap_get_config_identity(sm, &identity_len);
 151         if (identity == NULL)
 152                 return NULL;
 153
 154         if (data->state != LEAP_WAIT_SUCCESS) {
 155                 wpa_printf(MSG_INFO, "EAP-LEAP: EAP-Success received in "
 156                            "unexpected state (%d) - ignored", data->state);
 157                 ret->ignore = TRUE;
 158                 return NULL;
 159         }
 160
 161         resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_LEAP,
 162                              3 + LEAP_CHALLENGE_LEN + identity_len,
 163                              EAP_CODE_REQUEST, eap_get_id(reqData));
 164         if (resp == NULL)
 165                 return NULL;
 166         wpabuf_put_u8(resp, LEAP_VERSION);
 167         wpabuf_put_u8(resp, 0); /* unused */
 168         wpabuf_put_u8(resp, LEAP_CHALLENGE_LEN);
 169         pos = wpabuf_put(resp, LEAP_CHALLENGE_LEN);
 170         if (os_get_random(pos, LEAP_CHALLENGE_LEN)) {
 171                 wpa_printf(MSG_WARNING, "EAP-LEAP: Failed to read random data "
 172                            "for challenge");
 173                 wpabuf_free(resp);
 174                 ret->ignore = TRUE;
 175                 return NULL;
 176         }
 177         os_memcpy(data->ap_challenge, pos, LEAP_CHALLENGE_LEN);
 178         wpa_hexdump(MSG_MSGDUMP, "EAP-LEAP: Challenge to AP/AS", pos,
 179                     LEAP_CHALLENGE_LEN);
 180         wpabuf_put_data(resp, identity, identity_len);
 181
 182         data->state = LEAP_WAIT_RESPONSE;
 183
 184         return resp;
 185 }
 186
 187
 188 static struct wpabuf * eap_leap_process_response(struct eap_sm *sm, void *priv,
 189                                                  struct eap_method_ret *ret,
 190                                                  const struct wpabuf *reqData)
 191 {
 192         struct eap_leap_data *data = priv;
 193         const u8 *pos, *password;
 194         u8 response_len, pw_hash[16], pw_hash_hash[16],
 195                 expected[LEAP_RESPONSE_LEN];
 196         size_t password_len, len;
 197         int pwhash;
 198
 199         wpa_printf(MSG_DEBUG, "EAP-LEAP: Processing EAP-Response");
 200
 201         password = eap_get_config_password2(sm, &password_len, &pwhash);
 202         if (password == NULL)
 203                 return NULL;
 204
 205         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_LEAP, reqData, &len);
 206         if (pos == NULL || len < 3) {
 207                 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid EAP-Response frame");
 208                 ret->ignore = TRUE;
 209                 return NULL;
 210         }
 211
 212         if (*pos != LEAP_VERSION) {
 213                 wpa_printf(MSG_WARNING, "EAP-LEAP: Unsupported LEAP version "
 214                            "%d", *pos);
 215                 ret->ignore = TRUE;
 216                 return NULL;
 217         }
 218         pos++;
 219
 220         pos++; /* skip unused byte */
 221
 222         response_len = *pos++;
 223         if (response_len != LEAP_RESPONSE_LEN || response_len > len - 3) {
 224                 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid response "
 225                            "(response_len=%d reqDataLen=%lu)",
 226                            response_len, (unsigned long) wpabuf_len(reqData));
 227                 ret->ignore = TRUE;
 228                 return NULL;
 229         }
 230
 231         wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Response from AP",
 232                     pos, LEAP_RESPONSE_LEN);
 233         os_memcpy(data->ap_response, pos, LEAP_RESPONSE_LEN);
 234
 235         if (pwhash) {
 236                 if (hash_nt_password_hash(password, pw_hash_hash)) {
 237                         ret->ignore = TRUE;
 238                         return NULL;
 239                 }
 240         } else {
 241                 if (nt_password_hash(password, password_len, pw_hash) ||
 242                     hash_nt_password_hash(pw_hash, pw_hash_hash)) {
 243                         ret->ignore = TRUE;
 244                         return NULL;
 245                 }
 246         }
 247         challenge_response(data->ap_challenge, pw_hash_hash, expected);
 248
 249         ret->methodState = METHOD_DONE;
 250         ret->allowNotifications = FALSE;
 251
 252         if (os_memcmp(pos, expected, LEAP_RESPONSE_LEN) != 0) {
 253                 wpa_printf(MSG_WARNING, "EAP-LEAP: AP sent an invalid "
 254                            "response - authentication failed");
 255                 wpa_hexdump(MSG_DEBUG, "EAP-LEAP: Expected response from AP",
 256                             expected, LEAP_RESPONSE_LEN);
 257                 ret->decision = DECISION_FAIL;
 258                 return NULL;
 259         }
 260
 261         ret->decision = DECISION_UNCOND_SUCC;
 262
 263         /* LEAP is somewhat odd method since it sends EAP-Success in the middle
 264          * of the authentication. Use special variable to transit EAP state
 265          * machine to SUCCESS state. */
 266         sm->leap_done = TRUE;
 267         data->state = LEAP_DONE;
 268
 269         /* No more authentication messages expected; AP will send EAPOL-Key
 270          * frames if encryption is enabled. */
 271         return NULL;
 272 }
 273
 274
 275 static struct wpabuf * eap_leap_process(struct eap_sm *sm, void *priv,
 276                                         struct eap_method_ret *ret,
 277                                         const struct wpabuf *reqData)
 278 {
 279         const struct eap_hdr *eap;
 280         size_t password_len;
 281         const u8 *password;
 282
 283         password = eap_get_config_password(sm, &password_len);
 284         if (password == NULL) {
 285                 wpa_printf(MSG_INFO, "EAP-LEAP: Password not configured");
 286                 eap_sm_request_password(sm);
 287                 ret->ignore = TRUE;
 288                 return NULL;
 289         }
 290
 291         /*
 292          * LEAP needs to be able to handle EAP-Success frame which does not
 293          * include Type field. Consequently, eap_hdr_validate() cannot be used
 294          * here. This validation will be done separately for EAP-Request and
 295          * EAP-Response frames.
 296          */
 297         eap = wpabuf_head(reqData);
 298         if (wpabuf_len(reqData) < sizeof(*eap) ||
 299             be_to_host16(eap->length) > wpabuf_len(reqData)) {
 300                 wpa_printf(MSG_INFO, "EAP-LEAP: Invalid frame");
 301                 ret->ignore = TRUE;
 302                 return NULL;
 303         }
 304
 305         ret->ignore = FALSE;
 306         ret->allowNotifications = TRUE;
 307         ret->methodState = METHOD_MAY_CONT;
 308         ret->decision = DECISION_FAIL;
 309
 310         sm->leap_done = FALSE;
 311
 312         switch (eap->code) {
 313         case EAP_CODE_REQUEST:
 314                 return eap_leap_process_request(sm, priv, ret, reqData);
 315         case EAP_CODE_SUCCESS:
 316                 return eap_leap_process_success(sm, priv, ret, reqData);
 317         case EAP_CODE_RESPONSE:
 318                 return eap_leap_process_response(sm, priv, ret, reqData);
 319         default:
 320                 wpa_printf(MSG_INFO, "EAP-LEAP: Unexpected EAP code (%d) - "
 321                            "ignored", eap->code);
 322                 ret->ignore = TRUE;
 323                 return NULL;
 324         }
 325 }
 326
 327
 328 static Boolean eap_leap_isKeyAvailable(struct eap_sm *sm, void *priv)
 329 {
 330         struct eap_leap_data *data = priv;
 331         return data->state == LEAP_DONE;
 332 }
 333
 334
 335 static u8 * eap_leap_getKey(struct eap_sm *sm, void *priv, size_t *len)
 336 {
 337         struct eap_leap_data *data = priv;
 338         u8 *key, pw_hash_hash[16], pw_hash[16];
 339         const u8 *addr[5], *password;
 340         size_t elen[5], password_len;
 341         int pwhash;
 342
 343         if (data->state != LEAP_DONE)
 344                 return NULL;
 345
 346         password = eap_get_config_password2(sm, &password_len, &pwhash);
 347         if (password == NULL)
 348                 return NULL;
 349
 350         key = os_malloc(LEAP_KEY_LEN);
 351         if (key == NULL)
 352                 return NULL;
 353
 354         if (pwhash) {
 355                 if (hash_nt_password_hash(password, pw_hash_hash)) {
 356                         os_free(key);
 357                         return NULL;
 358                 }
 359         } else {
 360                 if (nt_password_hash(password, password_len, pw_hash) ||
 361                     hash_nt_password_hash(pw_hash, pw_hash_hash)) {
 362                         os_free(key);
 363                         return NULL;
 364                 }
 365         }
 366         wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: pw_hash_hash",
 367                         pw_hash_hash, 16);
 368         wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_challenge",
 369                     data->peer_challenge, LEAP_CHALLENGE_LEN);
 370         wpa_hexdump(MSG_DEBUG, "EAP-LEAP: peer_response",
 371                     data->peer_response, LEAP_RESPONSE_LEN);
 372         wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_challenge",
 373                     data->ap_challenge, LEAP_CHALLENGE_LEN);
 374         wpa_hexdump(MSG_DEBUG, "EAP-LEAP: ap_response",
 375                     data->ap_response, LEAP_RESPONSE_LEN);
 376
 377         addr[0] = pw_hash_hash;
 378         elen[0] = 16;
 379         addr[1] = data->ap_challenge;
 380         elen[1] = LEAP_CHALLENGE_LEN;
 381         addr[2] = data->ap_response;
 382         elen[2] = LEAP_RESPONSE_LEN;
 383         addr[3] = data->peer_challenge;
 384         elen[3] = LEAP_CHALLENGE_LEN;
 385         addr[4] = data->peer_response;
 386         elen[4] = LEAP_RESPONSE_LEN;
 387         md5_vector(5, addr, elen, key);
 388         wpa_hexdump_key(MSG_DEBUG, "EAP-LEAP: master key", key, LEAP_KEY_LEN);
 389         *len = LEAP_KEY_LEN;
 390
 391         return key;
 392 }
 393
 394
 395 int eap_peer_leap_register(void)
 396 {
 397         struct eap_method *eap;
 398         int ret;
 399
 400         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 401                                     EAP_VENDOR_IETF, EAP_TYPE_LEAP, "LEAP");
 402         if (eap == NULL)
 403                 return -1;
 404
 405         eap->init = eap_leap_init;
 406         eap->deinit = eap_leap_deinit;
 407         eap->process = eap_leap_process;
 408         eap->isKeyAvailable = eap_leap_isKeyAvailable;
 409         eap->getKey = eap_leap_getKey;
 410
 411         ret = eap_peer_method_register(eap);
 412         if (ret)
 413                 eap_peer_method_free(eap);
 414         return ret;
 415 }