contrib/hostapd-0.5.8/eap.c

   1 /*
   2  * hostapd / EAP Standalone Authenticator state machine (RFC 4137)
   3  * Copyright (c) 2004-2006, 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 "hostapd.h"
  18 #include "sta_info.h"
  19 #include "eap_i.h"
  20 #include "state_machine.h"
  21
  22 #define STATE_MACHINE_DATA struct eap_sm
  23 #define STATE_MACHINE_DEBUG_PREFIX "EAP"
  24
  25 #define EAP_MAX_AUTH_ROUNDS 50
  26
  27 static void eap_user_free(struct eap_user *user);
  28
  29
  30 /* EAP state machines are described in RFC 4137 */
  31
  32 static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount,
  33                                    int eapSRTT, int eapRTTVAR,
  34                                    int methodTimeout);
  35 static void eap_sm_parseEapResp(struct eap_sm *sm, u8 *resp, size_t len);
  36 static u8 * eap_sm_buildSuccess(struct eap_sm *sm, int id, size_t *len);
  37 static u8 * eap_sm_buildFailure(struct eap_sm *sm, int id, size_t *len);
  38 static int eap_sm_nextId(struct eap_sm *sm, int id);
  39 static void eap_sm_Policy_update(struct eap_sm *sm, u8 *nak_list, size_t len);
  40 static EapType eap_sm_Policy_getNextMethod(struct eap_sm *sm, int *vendor);
  41 static int eap_sm_Policy_getDecision(struct eap_sm *sm);
  42 static Boolean eap_sm_Policy_doPickUp(struct eap_sm *sm, EapType method);
  43
  44
  45 static Boolean eapol_get_bool(struct eap_sm *sm, enum eapol_bool_var var)
  46 {
  47         return sm->eapol_cb->get_bool(sm->eapol_ctx, var);
  48 }
  49
  50
  51 static void eapol_set_bool(struct eap_sm *sm, enum eapol_bool_var var,
  52                            Boolean value)
  53 {
  54         sm->eapol_cb->set_bool(sm->eapol_ctx, var, value);
  55 }
  56
  57
  58 static void eapol_set_eapReqData(struct eap_sm *sm,
  59                                  const u8 *eapReqData, size_t eapReqDataLen)
  60 {
  61         wpa_hexdump(MSG_MSGDUMP, "EAP: eapReqData -> EAPOL",
  62                     sm->eapReqData, sm->eapReqDataLen);
  63         sm->eapol_cb->set_eapReqData(sm->eapol_ctx, eapReqData, eapReqDataLen);
  64 }
  65
  66
  67 static void eapol_set_eapKeyData(struct eap_sm *sm,
  68                                  const u8 *eapKeyData, size_t eapKeyDataLen)
  69 {
  70         wpa_hexdump(MSG_MSGDUMP, "EAP: eapKeyData -> EAPOL",
  71                     sm->eapKeyData, sm->eapKeyDataLen);
  72         sm->eapol_cb->set_eapKeyData(sm->eapol_ctx, eapKeyData, eapKeyDataLen);
  73 }
  74
  75
  76 /**
  77  * eap_user_get - Fetch user information from the database
  78  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
  79  * @identity: Identity (User-Name) of the user
  80  * @identity_len: Length of identity in bytes
  81  * @phase2: 0 = EAP phase1 user, 1 = EAP phase2 (tunneled) user
  82  * Returns: 0 on success, or -1 on failure
  83  *
  84  * This function is used to fetch user information for EAP. The user will be
  85  * selected based on the specified identity. sm->user and
  86  * sm->user_eap_method_index are updated for the new user when a matching user
  87  * is found. sm->user can be used to get user information (e.g., password).
  88  */
  89 int eap_user_get(struct eap_sm *sm, const u8 *identity, size_t identity_len,
  90                  int phase2)
  91 {
  92         struct eap_user *user;
  93
  94         if (sm == NULL || sm->eapol_cb == NULL ||
  95             sm->eapol_cb->get_eap_user == NULL)
  96                 return -1;
  97
  98         eap_user_free(sm->user);
  99         sm->user = NULL;
 100
 101         user = wpa_zalloc(sizeof(*user));
 102         if (user == NULL)
 103             return -1;
 104
 105         if (sm->eapol_cb->get_eap_user(sm->eapol_ctx, identity,
 106                                        identity_len, phase2, user) != 0) {
 107                 eap_user_free(user);
 108                 return -1;
 109         }
 110
 111         sm->user = user;
 112         sm->user_eap_method_index = 0;
 113
 114         return 0;
 115 }
 116
 117
 118 SM_STATE(EAP, DISABLED)
 119 {
 120         SM_ENTRY(EAP, DISABLED);
 121         sm->num_rounds = 0;
 122 }
 123
 124
 125 SM_STATE(EAP, INITIALIZE)
 126 {
 127         SM_ENTRY(EAP, INITIALIZE);
 128
 129         sm->currentId = -1;
 130         eapol_set_bool(sm, EAPOL_eapSuccess, FALSE);
 131         eapol_set_bool(sm, EAPOL_eapFail, FALSE);
 132         eapol_set_bool(sm, EAPOL_eapTimeout, FALSE);
 133         free(sm->eapKeyData);
 134         sm->eapKeyData = NULL;
 135         sm->eapKeyDataLen = 0;
 136         /* eapKeyAvailable = FALSE */
 137         eapol_set_bool(sm, EAPOL_eapRestart, FALSE);
 138
 139         /*
 140          * This is not defined in RFC 4137, but method state needs to be
 141          * reseted here so that it does not remain in success state when
 142          * re-authentication starts.
 143          */
 144         if (sm->m && sm->eap_method_priv) {
 145                 sm->m->reset(sm, sm->eap_method_priv);
 146                 sm->eap_method_priv = NULL;
 147         }
 148         sm->m = NULL;
 149         sm->user_eap_method_index = 0;
 150
 151         if (sm->backend_auth) {
 152                 sm->currentMethod = EAP_TYPE_NONE;
 153                 /* parse rxResp, respId, respMethod */
 154                 eap_sm_parseEapResp(sm, sm->eapRespData, sm->eapRespDataLen);
 155                 if (sm->rxResp) {
 156                         sm->currentId = sm->respId;
 157                 }
 158         }
 159         sm->num_rounds = 0;
 160         sm->method_pending = METHOD_PENDING_NONE;
 161 }
 162
 163
 164 SM_STATE(EAP, PICK_UP_METHOD)
 165 {
 166         SM_ENTRY(EAP, PICK_UP_METHOD);
 167
 168         if (eap_sm_Policy_doPickUp(sm, sm->respMethod)) {
 169                 sm->currentMethod = sm->respMethod;
 170                 if (sm->m && sm->eap_method_priv) {
 171                         sm->m->reset(sm, sm->eap_method_priv);
 172                         sm->eap_method_priv = NULL;
 173                 }
 174                 sm->m = eap_sm_get_eap_methods(EAP_VENDOR_IETF,
 175                                                sm->currentMethod);
 176                 if (sm->m && sm->m->initPickUp) {
 177                         sm->eap_method_priv = sm->m->initPickUp(sm);
 178                         if (sm->eap_method_priv == NULL) {
 179                                 wpa_printf(MSG_DEBUG, "EAP: Failed to "
 180                                            "initialize EAP method %d",
 181                                            sm->currentMethod);
 182                                 sm->m = NULL;
 183                                 sm->currentMethod = EAP_TYPE_NONE;
 184                         }
 185                 } else {
 186                         sm->m = NULL;
 187                         sm->currentMethod = EAP_TYPE_NONE;
 188                 }
 189         }
 190 }
 191
 192
 193 SM_STATE(EAP, IDLE)
 194 {
 195         SM_ENTRY(EAP, IDLE);
 196
 197         sm->retransWhile = eap_sm_calculateTimeout(sm, sm->retransCount,
 198                                                    sm->eapSRTT, sm->eapRTTVAR,
 199                                                    sm->methodTimeout);
 200 }
 201
 202
 203 SM_STATE(EAP, RETRANSMIT)
 204 {
 205         SM_ENTRY(EAP, RETRANSMIT);
 206
 207         /* TODO: Is this needed since EAPOL state machines take care of
 208          * retransmit? */
 209 }
 210
 211
 212 SM_STATE(EAP, RECEIVED)
 213 {
 214         SM_ENTRY(EAP, RECEIVED);
 215
 216         /* parse rxResp, respId, respMethod */
 217         eap_sm_parseEapResp(sm, sm->eapRespData, sm->eapRespDataLen);
 218         sm->num_rounds++;
 219 }
 220
 221
 222 SM_STATE(EAP, DISCARD)
 223 {
 224         SM_ENTRY(EAP, DISCARD);
 225         eapol_set_bool(sm, EAPOL_eapResp, FALSE);
 226         eapol_set_bool(sm, EAPOL_eapNoReq, TRUE);
 227 }
 228
 229
 230 SM_STATE(EAP, SEND_REQUEST)
 231 {
 232         SM_ENTRY(EAP, SEND_REQUEST);
 233
 234         sm->retransCount = 0;
 235         if (sm->eapReqData) {
 236                 eapol_set_eapReqData(sm, sm->eapReqData, sm->eapReqDataLen);
 237                 free(sm->lastReqData);
 238                 sm->lastReqData = sm->eapReqData;
 239                 sm->lastReqDataLen = sm->eapReqDataLen;
 240                 sm->eapReqData = NULL;
 241                 sm->eapReqDataLen = 0;
 242                 eapol_set_bool(sm, EAPOL_eapResp, FALSE);
 243                 eapol_set_bool(sm, EAPOL_eapReq, TRUE);
 244         } else {
 245                 wpa_printf(MSG_INFO, "EAP: SEND_REQUEST - no eapReqData");
 246                 eapol_set_bool(sm, EAPOL_eapResp, FALSE);
 247                 eapol_set_bool(sm, EAPOL_eapReq, FALSE);
 248                 eapol_set_bool(sm, EAPOL_eapNoReq, TRUE);
 249         }
 250 }
 251
 252
 253 SM_STATE(EAP, INTEGRITY_CHECK)
 254 {
 255         SM_ENTRY(EAP, INTEGRITY_CHECK);
 256
 257         if (sm->m->check) {
 258                 sm->ignore = sm->m->check(sm, sm->eap_method_priv,
 259                                           sm->eapRespData, sm->eapRespDataLen);
 260         }
 261 }
 262
 263
 264 SM_STATE(EAP, METHOD_REQUEST)
 265 {
 266         SM_ENTRY(EAP, METHOD_REQUEST);
 267
 268         if (sm->m == NULL) {
 269                 wpa_printf(MSG_DEBUG, "EAP: method not initialized");
 270                 return;
 271         }
 272
 273         sm->currentId = eap_sm_nextId(sm, sm->currentId);
 274         wpa_printf(MSG_DEBUG, "EAP: building EAP-Request: Identifier %d",
 275                    sm->currentId);
 276         sm->lastId = sm->currentId;
 277         free(sm->eapReqData);
 278         sm->eapReqData = sm->m->buildReq(sm, sm->eap_method_priv,
 279                                          sm->currentId, &sm->eapReqDataLen);
 280         if (sm->m->getTimeout)
 281                 sm->methodTimeout = sm->m->getTimeout(sm, sm->eap_method_priv);
 282         else
 283                 sm->methodTimeout = 0;
 284 }
 285
 286
 287 SM_STATE(EAP, METHOD_RESPONSE)
 288 {
 289         SM_ENTRY(EAP, METHOD_RESPONSE);
 290
 291         sm->m->process(sm, sm->eap_method_priv, sm->eapRespData,
 292                        sm->eapRespDataLen);
 293         if (sm->m->isDone(sm, sm->eap_method_priv)) {
 294                 eap_sm_Policy_update(sm, NULL, 0);
 295                 free(sm->eapKeyData);
 296                 if (sm->m->getKey) {
 297                         sm->eapKeyData = sm->m->getKey(sm, sm->eap_method_priv,
 298                                                        &sm->eapKeyDataLen);
 299                 } else {
 300                         sm->eapKeyData = NULL;
 301                         sm->eapKeyDataLen = 0;
 302                 }
 303                 sm->methodState = METHOD_END;
 304         } else {
 305                 sm->methodState = METHOD_CONTINUE;
 306         }
 307 }
 308
 309
 310 SM_STATE(EAP, PROPOSE_METHOD)
 311 {
 312         int vendor;
 313         EapType type;
 314
 315         SM_ENTRY(EAP, PROPOSE_METHOD);
 316
 317         type = eap_sm_Policy_getNextMethod(sm, &vendor);
 318         if (vendor == EAP_VENDOR_IETF)
 319                 sm->currentMethod = type;
 320         else
 321                 sm->currentMethod = EAP_TYPE_EXPANDED;
 322         if (sm->m && sm->eap_method_priv) {
 323                 sm->m->reset(sm, sm->eap_method_priv);
 324                 sm->eap_method_priv = NULL;
 325         }
 326         sm->m = eap_sm_get_eap_methods(vendor, type);
 327         if (sm->m) {
 328                 sm->eap_method_priv = sm->m->init(sm);
 329                 if (sm->eap_method_priv == NULL) {
 330                         wpa_printf(MSG_DEBUG, "EAP: Failed to initialize EAP "
 331                                    "method %d", sm->currentMethod);
 332                         sm->m = NULL;
 333                         sm->currentMethod = EAP_TYPE_NONE;
 334                 }
 335         }
 336         if (sm->currentMethod == EAP_TYPE_IDENTITY ||
 337             sm->currentMethod == EAP_TYPE_NOTIFICATION)
 338                 sm->methodState = METHOD_CONTINUE;
 339         else
 340                 sm->methodState = METHOD_PROPOSED;
 341 }
 342
 343
 344 SM_STATE(EAP, NAK)
 345 {
 346         struct eap_hdr *nak;
 347         size_t len = 0;
 348         u8 *pos, *nak_list = NULL;
 349
 350         SM_ENTRY(EAP, NAK);
 351
 352         if (sm->eap_method_priv) {
 353                 sm->m->reset(sm, sm->eap_method_priv);
 354                 sm->eap_method_priv = NULL;
 355         }
 356         sm->m = NULL;
 357
 358         nak = (struct eap_hdr *) sm->eapRespData;
 359         if (nak && sm->eapRespDataLen > sizeof(*nak)) {
 360                 len = ntohs(nak->length);
 361                 if (len > sm->eapRespDataLen)
 362                         len = sm->eapRespDataLen;
 363                 pos = (u8 *) (nak + 1);
 364                 len -= sizeof(*nak);
 365                 if (*pos == EAP_TYPE_NAK) {
 366                         pos++;
 367                         len--;
 368                         nak_list = pos;
 369                 }
 370         }
 371         eap_sm_Policy_update(sm, nak_list, len);
 372 }
 373
 374
 375 SM_STATE(EAP, SELECT_ACTION)
 376 {
 377         SM_ENTRY(EAP, SELECT_ACTION);
 378
 379         sm->decision = eap_sm_Policy_getDecision(sm);
 380 }
 381
 382
 383 SM_STATE(EAP, TIMEOUT_FAILURE)
 384 {
 385         SM_ENTRY(EAP, TIMEOUT_FAILURE);
 386
 387         eapol_set_bool(sm, EAPOL_eapTimeout, TRUE);
 388 }
 389
 390
 391 SM_STATE(EAP, FAILURE)
 392 {
 393         SM_ENTRY(EAP, FAILURE);
 394
 395         free(sm->eapReqData);
 396         sm->eapReqData = eap_sm_buildFailure(sm, sm->currentId,
 397                                              &sm->eapReqDataLen);
 398         if (sm->eapReqData) {
 399                 eapol_set_eapReqData(sm, sm->eapReqData, sm->eapReqDataLen);
 400                 free(sm->eapReqData);
 401                 sm->eapReqData = NULL;
 402                 sm->eapReqDataLen = 0;
 403         }
 404         free(sm->lastReqData);
 405         sm->lastReqData = NULL;
 406         sm->lastReqDataLen = 0;
 407         eapol_set_bool(sm, EAPOL_eapFail, TRUE);
 408 }
 409
 410
 411 SM_STATE(EAP, SUCCESS)
 412 {
 413         SM_ENTRY(EAP, SUCCESS);
 414
 415         free(sm->eapReqData);
 416         sm->eapReqData = eap_sm_buildSuccess(sm, sm->currentId,
 417                                              &sm->eapReqDataLen);
 418         if (sm->eapReqData) {
 419                 eapol_set_eapReqData(sm, sm->eapReqData, sm->eapReqDataLen);
 420                 free(sm->eapReqData);
 421                 sm->eapReqData = NULL;
 422                 sm->eapReqDataLen = 0;
 423         }
 424         free(sm->lastReqData);
 425         sm->lastReqData = NULL;
 426         sm->lastReqDataLen = 0;
 427         if (sm->eapKeyData) {
 428                 eapol_set_eapKeyData(sm, sm->eapKeyData, sm->eapKeyDataLen);
 429         }
 430         eapol_set_bool(sm, EAPOL_eapSuccess, TRUE);
 431 }
 432
 433
 434 SM_STEP(EAP)
 435 {
 436         if (eapol_get_bool(sm, EAPOL_eapRestart) &&
 437             eapol_get_bool(sm, EAPOL_portEnabled))
 438                 SM_ENTER_GLOBAL(EAP, INITIALIZE);
 439         else if (!eapol_get_bool(sm, EAPOL_portEnabled))
 440                 SM_ENTER_GLOBAL(EAP, DISABLED);
 441         else if (sm->num_rounds > EAP_MAX_AUTH_ROUNDS) {
 442                 if (sm->num_rounds == EAP_MAX_AUTH_ROUNDS + 1) {
 443                         wpa_printf(MSG_DEBUG, "EAP: more than %d "
 444                                    "authentication rounds - abort",
 445                                    EAP_MAX_AUTH_ROUNDS);
 446                         sm->num_rounds++;
 447                         SM_ENTER_GLOBAL(EAP, FAILURE);
 448                 }
 449         } else switch (sm->EAP_state) {
 450         case EAP_INITIALIZE:
 451                 if (sm->backend_auth) {
 452                         if (!sm->rxResp)
 453                                 SM_ENTER(EAP, SELECT_ACTION);
 454                         else if (sm->rxResp &&
 455                                  (sm->respMethod == EAP_TYPE_NAK ||
 456                                   (sm->respMethod == EAP_TYPE_EXPANDED &&
 457                                    sm->respVendor == EAP_VENDOR_IETF &&
 458                                    sm->respVendorMethod == EAP_TYPE_NAK)))
 459                                 SM_ENTER(EAP, NAK);
 460                         else
 461                                 SM_ENTER(EAP, PICK_UP_METHOD);
 462                 } else {
 463                         SM_ENTER(EAP, SELECT_ACTION);
 464                 }
 465                 break;
 466         case EAP_PICK_UP_METHOD:
 467                 if (sm->currentMethod == EAP_TYPE_NONE) {
 468                         SM_ENTER(EAP, SELECT_ACTION);
 469                 } else {
 470                         SM_ENTER(EAP, METHOD_RESPONSE);
 471                 }
 472                 break;
 473         case EAP_DISABLED:
 474                 if (eapol_get_bool(sm, EAPOL_portEnabled))
 475                         SM_ENTER(EAP, INITIALIZE);
 476                 break;
 477         case EAP_IDLE:
 478                 if (sm->retransWhile == 0)
 479                         SM_ENTER(EAP, RETRANSMIT);
 480                 else if (eapol_get_bool(sm, EAPOL_eapResp))
 481                         SM_ENTER(EAP, RECEIVED);
 482                 break;
 483         case EAP_RETRANSMIT:
 484                 if (sm->retransCount > sm->MaxRetrans)
 485                         SM_ENTER(EAP, TIMEOUT_FAILURE);
 486                 else
 487                         SM_ENTER(EAP, IDLE);
 488                 break;
 489         case EAP_RECEIVED:
 490                 if (sm->rxResp && (sm->respId == sm->currentId) &&
 491                     (sm->respMethod == EAP_TYPE_NAK ||
 492                      (sm->respMethod == EAP_TYPE_EXPANDED &&
 493                       sm->respVendor == EAP_VENDOR_IETF &&
 494                       sm->respVendorMethod == EAP_TYPE_NAK))
 495                     && (sm->methodState == METHOD_PROPOSED))
 496                         SM_ENTER(EAP, NAK);
 497                 else if (sm->rxResp && (sm->respId == sm->currentId) &&
 498                          ((sm->respMethod == sm->currentMethod) ||
 499                           (sm->respMethod == EAP_TYPE_EXPANDED &&
 500                            sm->respVendor == EAP_VENDOR_IETF &&
 501                            sm->respVendorMethod == sm->currentMethod)))
 502                         SM_ENTER(EAP, INTEGRITY_CHECK);
 503                 else {
 504                         wpa_printf(MSG_DEBUG, "EAP: RECEIVED->DISCARD: "
 505                                    "rxResp=%d respId=%d currentId=%d "
 506                                    "respMethod=%d currentMethod=%d",
 507                                    sm->rxResp, sm->respId, sm->currentId,
 508                                    sm->respMethod, sm->currentMethod);
 509                         SM_ENTER(EAP, DISCARD);
 510                 }
 511                 break;
 512         case EAP_DISCARD:
 513                 SM_ENTER(EAP, IDLE);
 514                 break;
 515         case EAP_SEND_REQUEST:
 516                 SM_ENTER(EAP, IDLE);
 517                 break;
 518         case EAP_INTEGRITY_CHECK:
 519                 if (sm->ignore)
 520                         SM_ENTER(EAP, DISCARD);
 521                 else
 522                         SM_ENTER(EAP, METHOD_RESPONSE);
 523                 break;
 524         case EAP_METHOD_REQUEST:
 525                 SM_ENTER(EAP, SEND_REQUEST);
 526                 break;
 527         case EAP_METHOD_RESPONSE:
 528                 /*
 529                  * Note: Mechanism to allow EAP methods to wait while going
 530                  * through pending processing is an extension to RFC 4137
 531                  * which only defines the transits to SELECT_ACTION and
 532                  * METHOD_REQUEST from this METHOD_RESPONSE state.
 533                  */
 534                 if (sm->methodState == METHOD_END)
 535                         SM_ENTER(EAP, SELECT_ACTION);
 536                 else if (sm->method_pending == METHOD_PENDING_WAIT) {
 537                         wpa_printf(MSG_DEBUG, "EAP: Method has pending "
 538                                    "processing - wait before proceeding to "
 539                                    "METHOD_REQUEST state");
 540                 } else if (sm->method_pending == METHOD_PENDING_CONT) {
 541                         wpa_printf(MSG_DEBUG, "EAP: Method has completed "
 542                                    "pending processing - reprocess pending "
 543                                    "EAP message");
 544                         sm->method_pending = METHOD_PENDING_NONE;
 545                         SM_ENTER(EAP, METHOD_RESPONSE);
 546                 } else
 547                         SM_ENTER(EAP, METHOD_REQUEST);
 548                 break;
 549         case EAP_PROPOSE_METHOD:
 550                 /*
 551                  * Note: Mechanism to allow EAP methods to wait while going
 552                  * through pending processing is an extension to RFC 4137
 553                  * which only defines the transit to METHOD_REQUEST from this
 554                  * PROPOSE_METHOD state.
 555                  */
 556                 if (sm->method_pending == METHOD_PENDING_WAIT) {
 557                         wpa_printf(MSG_DEBUG, "EAP: Method has pending "
 558                                    "processing - wait before proceeding to "
 559                                    "METHOD_REQUEST state");
 560                         if (sm->user_eap_method_index > 0)
 561                                 sm->user_eap_method_index--;
 562                 } else if (sm->method_pending == METHOD_PENDING_CONT) {
 563                         wpa_printf(MSG_DEBUG, "EAP: Method has completed "
 564                                    "pending processing - reprocess pending "
 565                                    "EAP message");
 566                         sm->method_pending = METHOD_PENDING_NONE;
 567                         SM_ENTER(EAP, PROPOSE_METHOD);
 568                 } else
 569                         SM_ENTER(EAP, METHOD_REQUEST);
 570                 break;
 571         case EAP_NAK:
 572                 SM_ENTER(EAP, SELECT_ACTION);
 573                 break;
 574         case EAP_SELECT_ACTION:
 575                 if (sm->decision == DECISION_FAILURE)
 576                         SM_ENTER(EAP, FAILURE);
 577                 else if (sm->decision == DECISION_SUCCESS)
 578                         SM_ENTER(EAP, SUCCESS);
 579                 else
 580                         SM_ENTER(EAP, PROPOSE_METHOD);
 581                 break;
 582         case EAP_TIMEOUT_FAILURE:
 583                 break;
 584         case EAP_FAILURE:
 585                 break;
 586         case EAP_SUCCESS:
 587                 break;
 588         }
 589 }
 590
 591
 592 static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount,
 593                                    int eapSRTT, int eapRTTVAR,
 594                                    int methodTimeout)
 595 {
 596         /* For now, retransmission is done in EAPOL state machines, so make
 597          * sure EAP state machine does not end up trying to retransmit packets.
 598          */
 599         return 1;
 600 }
 601
 602
 603 static void eap_sm_parseEapResp(struct eap_sm *sm, u8 *resp, size_t len)
 604 {
 605         struct eap_hdr *hdr;
 606         size_t plen;
 607
 608         /* parse rxResp, respId, respMethod */
 609         sm->rxResp = FALSE;
 610         sm->respId = -1;
 611         sm->respMethod = EAP_TYPE_NONE;
 612         sm->respVendor = EAP_VENDOR_IETF;
 613         sm->respVendorMethod = EAP_TYPE_NONE;
 614
 615         if (resp == NULL || len < sizeof(*hdr))
 616                 return;
 617
 618         hdr = (struct eap_hdr *) resp;
 619         plen = ntohs(hdr->length);
 620         if (plen > len) {
 621                 wpa_printf(MSG_DEBUG, "EAP: Ignored truncated EAP-Packet "
 622                            "(len=%lu plen=%lu)", (unsigned long) len,
 623                            (unsigned long) plen);
 624                 return;
 625         }
 626
 627         sm->respId = hdr->identifier;
 628
 629         if (hdr->code == EAP_CODE_RESPONSE)
 630                 sm->rxResp = TRUE;
 631
 632         if (plen > sizeof(*hdr)) {
 633                 u8 *pos = (u8 *) (hdr + 1);
 634                 sm->respMethod = *pos++;
 635                 if (sm->respMethod == EAP_TYPE_EXPANDED) {
 636                         if (plen < sizeof(*hdr) + 8) {
 637                                 wpa_printf(MSG_DEBUG, "EAP: Ignored truncated "
 638                                            "expanded EAP-Packet (plen=%lu)",
 639                                            (unsigned long) plen);
 640                                 return;
 641                         }
 642                         sm->respVendor = WPA_GET_BE24(pos);
 643                         pos += 3;
 644                         sm->respVendorMethod = WPA_GET_BE32(pos);
 645                 }
 646         }
 647
 648         wpa_printf(MSG_DEBUG, "EAP: parseEapResp: rxResp=%d respId=%d "
 649                    "respMethod=%u respVendor=%u respVendorMethod=%u",
 650                    sm->rxResp, sm->respId, sm->respMethod, sm->respVendor,
 651                    sm->respVendorMethod);
 652 }
 653
 654
 655 static u8 * eap_sm_buildSuccess(struct eap_sm *sm, int id, size_t *len)
 656 {
 657         struct eap_hdr *resp;
 658         wpa_printf(MSG_DEBUG, "EAP: Building EAP-Success (id=%d)", id);
 659
 660         *len = sizeof(*resp);
 661         resp = malloc(*len);
 662         if (resp == NULL)
 663                 return NULL;
 664         resp->code = EAP_CODE_SUCCESS;
 665         resp->identifier = id;
 666         resp->length = htons(*len);
 667
 668         return (u8 *) resp;
 669 }
 670
 671
 672 static u8 * eap_sm_buildFailure(struct eap_sm *sm, int id, size_t *len)
 673 {
 674         struct eap_hdr *resp;
 675         wpa_printf(MSG_DEBUG, "EAP: Building EAP-Failure (id=%d)", id);
 676
 677         *len = sizeof(*resp);
 678         resp = malloc(*len);
 679         if (resp == NULL)
 680                 return NULL;
 681         resp->code = EAP_CODE_FAILURE;
 682         resp->identifier = id;
 683         resp->length = htons(*len);
 684
 685         return (u8 *) resp;
 686 }
 687
 688
 689 static int eap_sm_nextId(struct eap_sm *sm, int id)
 690 {
 691         if (id < 0) {
 692                 /* RFC 3748 Ch 4.1: recommended to initialize Identifier with a
 693                  * random number */
 694                 id = rand() & 0xff;
 695                 if (id != sm->lastId)
 696                         return id;
 697         }
 698         return (id + 1) & 0xff;
 699 }
 700
 701
 702 /**
 703  * eap_sm_process_nak - Process EAP-Response/Nak
 704  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 705  * @nak_list: Nak list (allowed methods) from the supplicant
 706  * @len: Length of nak_list in bytes
 707  *
 708  * This function is called when EAP-Response/Nak is received from the
 709  * supplicant. This can happen for both phase 1 and phase 2 authentications.
 710  */
 711 void eap_sm_process_nak(struct eap_sm *sm, u8 *nak_list, size_t len)
 712 {
 713         int i;
 714         size_t j;
 715
 716         if (sm->user == NULL)
 717                 return;
 718
 719         wpa_printf(MSG_MSGDUMP, "EAP: processing NAK (current EAP method "
 720                    "index %d)", sm->user_eap_method_index);
 721
 722         wpa_hexdump(MSG_MSGDUMP, "EAP: configured methods",
 723                     (u8 *) sm->user->methods,
 724                     EAP_MAX_METHODS * sizeof(sm->user->methods[0]));
 725         wpa_hexdump(MSG_MSGDUMP, "EAP: list of methods supported by the peer",
 726                     nak_list, len);
 727
 728         i = sm->user_eap_method_index;
 729         while (i < EAP_MAX_METHODS &&
 730                (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
 731                 sm->user->methods[i].method != EAP_TYPE_NONE)) {
 732                 if (sm->user->methods[i].vendor != EAP_VENDOR_IETF)
 733                         goto not_found;
 734                 for (j = 0; j < len; j++) {
 735                         if (nak_list[j] == sm->user->methods[i].method) {
 736                                 break;
 737                         }
 738                 }
 739
 740                 if (j < len) {
 741                         /* found */
 742                         i++;
 743                         continue;
 744                 }
 745
 746         not_found:
 747                 /* not found - remove from the list */
 748                 memmove(&sm->user->methods[i], &sm->user->methods[i + 1],
 749                         (EAP_MAX_METHODS - i - 1) *
 750                         sizeof(sm->user->methods[0]));
 751                 sm->user->methods[EAP_MAX_METHODS - 1].vendor =
 752                         EAP_VENDOR_IETF;
 753                 sm->user->methods[EAP_MAX_METHODS - 1].method = EAP_TYPE_NONE;
 754         }
 755
 756         wpa_hexdump(MSG_MSGDUMP, "EAP: new list of configured methods",
 757                     (u8 *) sm->user->methods, EAP_MAX_METHODS *
 758                     sizeof(sm->user->methods[0]));
 759 }
 760
 761
 762 static void eap_sm_Policy_update(struct eap_sm *sm, u8 *nak_list, size_t len)
 763 {
 764         if (nak_list == NULL || sm == NULL || sm->user == NULL)
 765                 return;
 766
 767         if (sm->user->phase2) {
 768                 wpa_printf(MSG_DEBUG, "EAP: EAP-Nak received after Phase2 user"
 769                            " info was selected - reject");
 770                 sm->decision = DECISION_FAILURE;
 771                 return;
 772         }
 773
 774         eap_sm_process_nak(sm, nak_list, len);
 775 }
 776
 777
 778 static EapType eap_sm_Policy_getNextMethod(struct eap_sm *sm, int *vendor)
 779 {
 780         EapType next;
 781         int idx = sm->user_eap_method_index;
 782
 783         /* In theory, there should be no problems with starting
 784          * re-authentication with something else than EAP-Request/Identity and
 785          * this does indeed work with wpa_supplicant. However, at least Funk
 786          * Supplicant seemed to ignore re-auth if it skipped
 787          * EAP-Request/Identity.
 788          * Re-auth sets currentId == -1, so that can be used here to select
 789          * whether Identity needs to be requested again. */
 790         if (sm->identity == NULL || sm->currentId == -1) {
 791                 *vendor = EAP_VENDOR_IETF;
 792                 next = EAP_TYPE_IDENTITY;
 793                 sm->update_user = TRUE;
 794         } else if (sm->user && idx < EAP_MAX_METHODS &&
 795                    (sm->user->methods[idx].vendor != EAP_VENDOR_IETF ||
 796                     sm->user->methods[idx].method != EAP_TYPE_NONE)) {
 797                 *vendor = sm->user->methods[idx].vendor;
 798                 next = sm->user->methods[idx].method;
 799                 sm->user_eap_method_index++;
 800         } else {
 801                 *vendor = EAP_VENDOR_IETF;
 802                 next = EAP_TYPE_NONE;
 803         }
 804         wpa_printf(MSG_DEBUG, "EAP: getNextMethod: vendor %d type %d",
 805                    *vendor, next);
 806         return next;
 807 }
 808
 809
 810 static int eap_sm_Policy_getDecision(struct eap_sm *sm)
 811 {
 812         if (sm->m && sm->currentMethod != EAP_TYPE_IDENTITY &&
 813             sm->m->isSuccess(sm, sm->eap_method_priv)) {
 814                 wpa_printf(MSG_DEBUG, "EAP: getDecision: method succeeded -> "
 815                            "SUCCESS");
 816                 sm->update_user = TRUE;
 817                 return DECISION_SUCCESS;
 818         }
 819
 820         if (sm->m && sm->m->isDone(sm, sm->eap_method_priv) &&
 821             !sm->m->isSuccess(sm, sm->eap_method_priv)) {
 822                 wpa_printf(MSG_DEBUG, "EAP: getDecision: method failed -> "
 823                            "FAILURE");
 824                 sm->update_user = TRUE;
 825                 return DECISION_FAILURE;
 826         }
 827
 828         if ((sm->user == NULL || sm->update_user) && sm->identity) {
 829                 if (eap_user_get(sm, sm->identity, sm->identity_len, 0) != 0) {
 830                         wpa_printf(MSG_DEBUG, "EAP: getDecision: user not "
 831                                    "found from database -> FAILURE");
 832                         return DECISION_FAILURE;
 833                 }
 834                 sm->update_user = FALSE;
 835         }
 836
 837         if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS &&
 838             (sm->user->methods[sm->user_eap_method_index].vendor !=
 839              EAP_VENDOR_IETF ||
 840              sm->user->methods[sm->user_eap_method_index].method !=
 841              EAP_TYPE_NONE)) {
 842                 wpa_printf(MSG_DEBUG, "EAP: getDecision: another method "
 843                            "available -> CONTINUE");
 844                 return DECISION_CONTINUE;
 845         }
 846
 847         if (sm->identity == NULL || sm->currentId == -1) {
 848                 wpa_printf(MSG_DEBUG, "EAP: getDecision: no identity known "
 849                            "yet -> CONTINUE");
 850                 return DECISION_CONTINUE;
 851         }
 852
 853         wpa_printf(MSG_DEBUG, "EAP: getDecision: no more methods available -> "
 854                    "FAILURE");
 855         return DECISION_FAILURE;
 856 }
 857
 858
 859 static Boolean eap_sm_Policy_doPickUp(struct eap_sm *sm, EapType method)
 860 {
 861         return method == EAP_TYPE_IDENTITY ? TRUE : FALSE;
 862 }
 863
 864
 865 /**
 866  * eap_sm_step - Step EAP state machine
 867  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 868  * Returns: 1 if EAP state was changed or 0 if not
 869  *
 870  * This function advances EAP state machine to a new state to match with the
 871  * current variables. This should be called whenever variables used by the EAP
 872  * state machine have changed.
 873  */
 874 int eap_sm_step(struct eap_sm *sm)
 875 {
 876         int res = 0;
 877         do {
 878                 sm->changed = FALSE;
 879                 SM_STEP_RUN(EAP);
 880                 if (sm->changed)
 881                         res = 1;
 882         } while (sm->changed);
 883         return res;
 884 }
 885
 886
 887 /**
 888  * eap_set_eapRespData - Set EAP response (eapRespData)
 889  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 890  * @eapRespData: EAP-Response payload from the supplicant
 891  * @eapRespDataLen: Length of eapRespData in bytes
 892  *
 893  * This function is called when an EAP-Response is received from a supplicant.
 894  */
 895 void eap_set_eapRespData(struct eap_sm *sm, const u8 *eapRespData,
 896                          size_t eapRespDataLen)
 897 {
 898         if (sm == NULL)
 899                 return;
 900         free(sm->eapRespData);
 901         sm->eapRespData = malloc(eapRespDataLen);
 902         if (sm->eapRespData == NULL)
 903                 return;
 904         memcpy(sm->eapRespData, eapRespData, eapRespDataLen);
 905         sm->eapRespDataLen = eapRespDataLen;
 906         wpa_hexdump(MSG_MSGDUMP, "EAP: EAP-Response received",
 907                     eapRespData, eapRespDataLen);
 908 }
 909
 910
 911 static void eap_user_free(struct eap_user *user)
 912 {
 913         if (user == NULL)
 914                 return;
 915         free(user->password);
 916         user->password = NULL;
 917         free(user);
 918 }
 919
 920
 921 /**
 922  * eap_sm_init - Allocate and initialize EAP state machine
 923  * @eapol_ctx: Context data to be used with eapol_cb calls
 924  * @eapol_cb: Pointer to EAPOL callback functions
 925  * @conf: EAP configuration
 926  * Returns: Pointer to the allocated EAP state machine or %NULL on failure
 927  *
 928  * This function allocates and initializes an EAP state machine.
 929  */
 930 struct eap_sm * eap_sm_init(void *eapol_ctx, struct eapol_callbacks *eapol_cb,
 931                             struct eap_config *conf)
 932 {
 933         struct eap_sm *sm;
 934
 935         sm = wpa_zalloc(sizeof(*sm));
 936         if (sm == NULL)
 937                 return NULL;
 938         sm->eapol_ctx = eapol_ctx;
 939         sm->eapol_cb = eapol_cb;
 940         sm->MaxRetrans = 10;
 941         sm->ssl_ctx = conf->ssl_ctx;
 942         sm->eap_sim_db_priv = conf->eap_sim_db_priv;
 943         sm->backend_auth = conf->backend_auth;
 944
 945         wpa_printf(MSG_DEBUG, "EAP: State machine created");
 946
 947         return sm;
 948 }
 949
 950
 951 /**
 952  * eap_sm_deinit - Deinitialize and free an EAP state machine
 953  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 954  *
 955  * This function deinitializes EAP state machine and frees all allocated
 956  * resources.
 957  */
 958 void eap_sm_deinit(struct eap_sm *sm)
 959 {
 960         if (sm == NULL)
 961                 return;
 962         wpa_printf(MSG_DEBUG, "EAP: State machine removed");
 963         if (sm->m && sm->eap_method_priv)
 964                 sm->m->reset(sm, sm->eap_method_priv);
 965         free(sm->eapReqData);
 966         free(sm->eapKeyData);
 967         free(sm->lastReqData);
 968         free(sm->eapRespData);
 969         free(sm->identity);
 970         eap_user_free(sm->user);
 971         free(sm);
 972 }
 973
 974
 975 /**
 976  * eap_sm_notify_cached - Notify EAP state machine of cached PMK
 977  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 978  *
 979  * This function is called when PMKSA caching is used to skip EAP
 980  * authentication.
 981  */
 982 void eap_sm_notify_cached(struct eap_sm *sm)
 983 {
 984         if (sm == NULL)
 985                 return;
 986
 987         sm->EAP_state = EAP_SUCCESS;
 988 }
 989
 990
 991 /**
 992  * eap_sm_pending_cb - EAP state machine callback for a pending EAP request
 993  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
 994  *
 995  * This function is called when data for a pending EAP-Request is received.
 996  */
 997 void eap_sm_pending_cb(struct eap_sm *sm)
 998 {
 999         if (sm == NULL)
1000                 return;
1001         wpa_printf(MSG_DEBUG, "EAP: Callback for pending request received");
1002         if (sm->method_pending == METHOD_PENDING_WAIT)
1003                 sm->method_pending = METHOD_PENDING_CONT;
1004 }
1005
1006
1007 /**
1008  * eap_sm_method_pending - Query whether EAP method is waiting for pending data
1009  * @sm: Pointer to EAP state machine allocated with eap_sm_init()
1010  * Returns: 1 if method is waiting for pending data or 0 if not
1011  */
1012 int eap_sm_method_pending(struct eap_sm *sm)
1013 {
1014         if (sm == NULL)
1015                 return 0;
1016         return sm->method_pending == METHOD_PENDING_WAIT;
1017 }
1018
1019
1020 /**
1021  * eap_hdr_validate - Validate EAP header
1022  * @vendor: Expected EAP Vendor-Id (0 = IETF)
1023  * @eap_type: Expected EAP type number
1024  * @msg: EAP frame (starting with EAP header)
1025  * @msglen: Length of msg
1026  * @plen: Pointer to variable to contain the returned payload length
1027  * Returns: Pointer to EAP payload (after type field), or %NULL on failure
1028  *
1029  * This is a helper function for EAP method implementations. This is usually
1030  * called in the beginning of struct eap_method::process() function to verify
1031  * that the received EAP request packet has a valid header. This function is
1032  * able to process both legacy and expanded EAP headers and in most cases, the
1033  * caller can just use the returned payload pointer (into *plen) for processing
1034  * the payload regardless of whether the packet used the expanded EAP header or
1035  * not.
1036  */
1037 const u8 * eap_hdr_validate(int vendor, EapType eap_type,
1038                             const u8 *msg, size_t msglen, size_t *plen)
1039 {
1040         const struct eap_hdr *hdr;
1041         const u8 *pos;
1042         size_t len;
1043
1044         hdr = (const struct eap_hdr *) msg;
1045
1046         if (msglen < sizeof(*hdr)) {
1047                 wpa_printf(MSG_INFO, "EAP: Too short EAP frame");
1048                 return NULL;
1049         }
1050
1051         len = be_to_host16(hdr->length);
1052         if (len < sizeof(*hdr) + 1 || len > msglen) {
1053                 wpa_printf(MSG_INFO, "EAP: Invalid EAP length");
1054                 return NULL;
1055         }
1056
1057         pos = (const u8 *) (hdr + 1);
1058
1059         if (*pos == EAP_TYPE_EXPANDED) {
1060                 int exp_vendor;
1061                 u32 exp_type;
1062                 if (len < sizeof(*hdr) + 8) {
1063                         wpa_printf(MSG_INFO, "EAP: Invalid expanded EAP "
1064                                    "length");
1065                         return NULL;
1066                 }
1067                 pos++;
1068                 exp_vendor = WPA_GET_BE24(pos);
1069                 pos += 3;
1070                 exp_type = WPA_GET_BE32(pos);
1071                 pos += 4;
1072                 if (exp_vendor != vendor || exp_type != (u32) eap_type) {
1073                         wpa_printf(MSG_INFO, "EAP: Invalid expanded frame "
1074                                    "type");
1075                         return NULL;
1076                 }
1077
1078                 *plen = len - sizeof(*hdr) - 8;
1079                 return pos;
1080         } else {
1081                 if (vendor != EAP_VENDOR_IETF || *pos != eap_type) {
1082                         wpa_printf(MSG_INFO, "EAP: Invalid frame type");
1083                         return NULL;
1084                 }
1085                 *plen = len - sizeof(*hdr) - 1;
1086                 return pos + 1;
1087         }
1088 }
1089
1090
1091 /**
1092  * eap_msg_alloc - Allocate a buffer for an EAP message
1093  * @vendor: Vendor-Id (0 = IETF)
1094  * @type: EAP type
1095  * @len: Buffer for returning message length
1096  * @payload_len: Payload length in bytes (data after Type)
1097  * @code: Message Code (EAP_CODE_*)
1098  * @identifier: Identifier
1099  * @payload: Pointer to payload pointer that will be set to point to the
1100  * beginning of the payload or %NULL if payload pointer is not needed
1101  * Returns: Pointer to the allocated message buffer or %NULL on error
1102  *
1103  * This function can be used to allocate a buffer for an EAP message and fill
1104  * in the EAP header. This function is automatically using expanded EAP header
1105  * if the selected Vendor-Id is not IETF. In other words, most EAP methods do
1106  * not need to separately select which header type to use when using this
1107  * function to allocate the message buffers.
1108  */
1109 struct eap_hdr * eap_msg_alloc(int vendor, EapType type, size_t *len,
1110                                size_t payload_len, u8 code, u8 identifier,
1111                                u8 **payload)
1112 {
1113         struct eap_hdr *hdr;
1114         u8 *pos;
1115
1116         *len = sizeof(struct eap_hdr) + (vendor == EAP_VENDOR_IETF ? 1 : 8) +
1117                 payload_len;
1118         hdr = malloc(*len);
1119         if (hdr) {
1120                 hdr->code = code;
1121                 hdr->identifier = identifier;
1122                 hdr->length = host_to_be16(*len);
1123                 pos = (u8 *) (hdr + 1);
1124                 if (vendor == EAP_VENDOR_IETF) {
1125                         *pos++ = type;
1126                 } else {
1127                         *pos++ = EAP_TYPE_EXPANDED;
1128                         WPA_PUT_BE24(pos, vendor);
1129                         pos += 3;
1130                         WPA_PUT_BE32(pos, type);
1131                         pos += 4;
1132                 }
1133                 if (payload)
1134                         *payload = pos;
1135         }
1136
1137         return hdr;
1138 }