contrib/hostapd/eap_sim.c

   1 /*
   2  * hostapd / EAP-SIM (RFC 4186)
   3  * Copyright (c) 2005-2007, 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 "hostapd.h"
  18 #include "common.h"
  19 #include "crypto.h"
  20 #include "eap_i.h"
  21 #include "eap_sim_common.h"
  22 #include "eap_sim_db.h"
  23
  24
  25 struct eap_sim_data {
  26         u8 mk[EAP_SIM_MK_LEN];
  27         u8 nonce_mt[EAP_SIM_NONCE_MT_LEN];
  28         u8 nonce_s[EAP_SIM_NONCE_S_LEN];
  29         u8 k_aut[EAP_SIM_K_AUT_LEN];
  30         u8 k_encr[EAP_SIM_K_ENCR_LEN];
  31         u8 msk[EAP_SIM_KEYING_DATA_LEN];
  32         u8 emsk[EAP_EMSK_LEN];
  33         u8 kc[EAP_SIM_MAX_CHAL][EAP_SIM_KC_LEN];
  34         u8 sres[EAP_SIM_MAX_CHAL][EAP_SIM_SRES_LEN];
  35         u8 rand[EAP_SIM_MAX_CHAL][GSM_RAND_LEN];
  36         int num_chal;
  37         enum { START, CHALLENGE, REAUTH, SUCCESS, FAILURE } state;
  38         char *next_pseudonym;
  39         char *next_reauth_id;
  40         u16 counter;
  41         struct eap_sim_reauth *reauth;
  42 };
  43
  44
  45 static const char * eap_sim_state_txt(int state)
  46 {
  47         switch (state) {
  48         case START:
  49                 return "START";
  50         case CHALLENGE:
  51                 return "CHALLENGE";
  52         case REAUTH:
  53                 return "REAUTH";
  54         case SUCCESS:
  55                 return "SUCCESS";
  56         case FAILURE:
  57                 return "FAILURE";
  58         default:
  59                 return "Unknown?!";
  60         }
  61 }
  62
  63
  64 static void eap_sim_state(struct eap_sim_data *data, int state)
  65 {
  66         wpa_printf(MSG_DEBUG, "EAP-SIM: %s -> %s",
  67                    eap_sim_state_txt(data->state),
  68                    eap_sim_state_txt(state));
  69         data->state = state;
  70 }
  71
  72
  73 static void * eap_sim_init(struct eap_sm *sm)
  74 {
  75         struct eap_sim_data *data;
  76
  77         if (sm->eap_sim_db_priv == NULL) {
  78                 wpa_printf(MSG_WARNING, "EAP-SIM: eap_sim_db not configured");
  79                 return NULL;
  80         }
  81
  82         data = wpa_zalloc(sizeof(*data));
  83         if (data == NULL)
  84                 return NULL;
  85         data->state = START;
  86
  87         return data;
  88 }
  89
  90
  91 static void eap_sim_reset(struct eap_sm *sm, void *priv)
  92 {
  93         struct eap_sim_data *data = priv;
  94         free(data->next_pseudonym);
  95         free(data->next_reauth_id);
  96         free(data);
  97 }
  98
  99
 100 static u8 * eap_sim_build_start(struct eap_sm *sm, struct eap_sim_data *data,
 101                                 int id, size_t *reqDataLen)
 102 {
 103         struct eap_sim_msg *msg;
 104         u8 ver[2];
 105
 106         wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Start");
 107         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
 108                                EAP_SIM_SUBTYPE_START);
 109         if (eap_sim_db_identity_known(sm->eap_sim_db_priv, sm->identity,
 110                                       sm->identity_len)) {
 111                 wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
 112                 eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
 113         }
 114         wpa_printf(MSG_DEBUG, "   AT_VERSION_LIST");
 115         ver[0] = 0;
 116         ver[1] = EAP_SIM_VERSION;
 117         eap_sim_msg_add(msg, EAP_SIM_AT_VERSION_LIST, sizeof(ver),
 118                         ver, sizeof(ver));
 119         return eap_sim_msg_finish(msg, reqDataLen, NULL, NULL, 0);
 120 }
 121
 122
 123 static int eap_sim_build_encr(struct eap_sm *sm, struct eap_sim_data *data,
 124                               struct eap_sim_msg *msg, u16 counter,
 125                               const u8 *nonce_s)
 126 {
 127         free(data->next_pseudonym);
 128         data->next_pseudonym =
 129                 eap_sim_db_get_next_pseudonym(sm->eap_sim_db_priv, 0);
 130         free(data->next_reauth_id);
 131         if (data->counter <= EAP_SIM_MAX_FAST_REAUTHS) {
 132                 data->next_reauth_id =
 133                         eap_sim_db_get_next_reauth_id(sm->eap_sim_db_priv, 0);
 134         } else {
 135                 wpa_printf(MSG_DEBUG, "EAP-SIM: Max fast re-authentication "
 136                            "count exceeded - force full authentication");
 137                 data->next_reauth_id = NULL;
 138         }
 139
 140         if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
 141             counter == 0 && nonce_s == NULL)
 142                 return 0;
 143
 144         wpa_printf(MSG_DEBUG, "   AT_IV");
 145         wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
 146         eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
 147
 148         if (counter > 0) {
 149                 wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
 150                 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
 151         }
 152
 153         if (nonce_s) {
 154                 wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
 155                 eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
 156                                 EAP_SIM_NONCE_S_LEN);
 157         }
 158
 159         if (data->next_pseudonym) {
 160                 wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
 161                            data->next_pseudonym);
 162                 eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
 163                                 strlen(data->next_pseudonym),
 164                                 (u8 *) data->next_pseudonym,
 165                                 strlen(data->next_pseudonym));
 166         }
 167
 168         if (data->next_reauth_id) {
 169                 wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
 170                            data->next_reauth_id);
 171                 eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
 172                                 strlen(data->next_reauth_id),
 173                                 (u8 *) data->next_reauth_id,
 174                                 strlen(data->next_reauth_id));
 175         }
 176
 177         if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
 178                 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt "
 179                            "AT_ENCR_DATA");
 180                 return -1;
 181         }
 182
 183         return 0;
 184 }
 185
 186
 187 static u8 * eap_sim_build_challenge(struct eap_sm *sm,
 188                                     struct eap_sim_data *data,
 189                                     int id, size_t *reqDataLen)
 190 {
 191         struct eap_sim_msg *msg;
 192
 193         wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Challenge");
 194         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
 195                                EAP_SIM_SUBTYPE_CHALLENGE);
 196         wpa_printf(MSG_DEBUG, "   AT_RAND");
 197         eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, (u8 *) data->rand,
 198                         data->num_chal * GSM_RAND_LEN);
 199
 200         if (eap_sim_build_encr(sm, data, msg, 0, NULL)) {
 201                 eap_sim_msg_free(msg);
 202                 return NULL;
 203         }
 204
 205         wpa_printf(MSG_DEBUG, "   AT_MAC");
 206         eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
 207         return eap_sim_msg_finish(msg, reqDataLen, data->k_aut, data->nonce_mt,
 208                                   EAP_SIM_NONCE_MT_LEN);
 209 }
 210
 211
 212 static u8 * eap_sim_build_reauth(struct eap_sm *sm,
 213                                  struct eap_sim_data *data,
 214                                  int id, size_t *reqDataLen)
 215 {
 216         struct eap_sim_msg *msg;
 217
 218         wpa_printf(MSG_DEBUG, "EAP-SIM: Generating Re-authentication");
 219
 220         if (hostapd_get_rand(data->nonce_s, EAP_SIM_NONCE_S_LEN))
 221                 return NULL;
 222         wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: NONCE_S",
 223                         data->nonce_s, EAP_SIM_NONCE_S_LEN);
 224
 225         eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
 226                             data->emsk);
 227         eap_sim_derive_keys_reauth(data->counter, sm->identity,
 228                                    sm->identity_len, data->nonce_s, data->mk,
 229                                    data->msk, data->emsk);
 230
 231         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, EAP_TYPE_SIM,
 232                                EAP_SIM_SUBTYPE_REAUTHENTICATION);
 233
 234         if (eap_sim_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
 235                 eap_sim_msg_free(msg);
 236                 return NULL;
 237         }
 238
 239         wpa_printf(MSG_DEBUG, "   AT_MAC");
 240         eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
 241         return eap_sim_msg_finish(msg, reqDataLen, data->k_aut, NULL, 0);
 242 }
 243
 244
 245 static u8 * eap_sim_buildReq(struct eap_sm *sm, void *priv, int id,
 246                              size_t *reqDataLen)
 247 {
 248         struct eap_sim_data *data = priv;
 249
 250         switch (data->state) {
 251         case START:
 252                 return eap_sim_build_start(sm, data, id, reqDataLen);
 253         case CHALLENGE:
 254                 return eap_sim_build_challenge(sm, data, id, reqDataLen);
 255         case REAUTH:
 256                 return eap_sim_build_reauth(sm, data, id, reqDataLen);
 257         default:
 258                 wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
 259                            "buildReq", data->state);
 260                 break;
 261         }
 262         return NULL;
 263 }
 264
 265
 266 static Boolean eap_sim_check(struct eap_sm *sm, void *priv,
 267                              u8 *respData, size_t respDataLen)
 268 {
 269         struct eap_sim_data *data = priv;
 270         struct eap_hdr *resp;
 271         u8 *pos, subtype;
 272
 273         resp = (struct eap_hdr *) respData;
 274         pos = (u8 *) (resp + 1);
 275         if (respDataLen < sizeof(*resp) + 4 || *pos != EAP_TYPE_SIM ||
 276             (ntohs(resp->length)) > respDataLen) {
 277                 wpa_printf(MSG_INFO, "EAP-SIM: Invalid frame");
 278                 return TRUE;
 279         }
 280         subtype = pos[1];
 281
 282         if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR)
 283                 return FALSE;
 284
 285         switch (data->state) {
 286         case START:
 287                 if (subtype != EAP_SIM_SUBTYPE_START) {
 288                         wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
 289                                    "subtype %d", subtype);
 290                         return TRUE;
 291                 }
 292                 break;
 293         case CHALLENGE:
 294                 if (subtype != EAP_SIM_SUBTYPE_CHALLENGE) {
 295                         wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
 296                                    "subtype %d", subtype);
 297                         return TRUE;
 298                 }
 299                 break;
 300         case REAUTH:
 301                 if (subtype != EAP_SIM_SUBTYPE_REAUTHENTICATION) {
 302                         wpa_printf(MSG_INFO, "EAP-SIM: Unexpected response "
 303                                    "subtype %d", subtype);
 304                         return TRUE;
 305                 }
 306                 break;
 307         default:
 308                 wpa_printf(MSG_INFO, "EAP-SIM: Unexpected state (%d) for "
 309                            "processing a response", data->state);
 310                 return TRUE;
 311         }
 312
 313         return FALSE;
 314 }
 315
 316
 317 static int eap_sim_supported_ver(struct eap_sim_data *data, int version)
 318 {
 319         return version == EAP_SIM_VERSION;
 320 }
 321
 322
 323 static void eap_sim_process_start(struct eap_sm *sm,
 324                                   struct eap_sim_data *data,
 325                                   u8 *respData, size_t respDataLen,
 326                                   struct eap_sim_attrs *attr)
 327 {
 328         const u8 *identity;
 329         size_t identity_len;
 330         u8 ver_list[2];
 331
 332         wpa_printf(MSG_DEBUG, "EAP-SIM: Receive start response");
 333
 334         if (attr->nonce_mt == NULL || attr->selected_version < 0) {
 335                 wpa_printf(MSG_DEBUG, "EAP-SIM: Start/Response missing "
 336                            "required attributes");
 337                 eap_sim_state(data, FAILURE);
 338                 return;
 339         }
 340
 341         if (!eap_sim_supported_ver(data, attr->selected_version)) {
 342                 wpa_printf(MSG_DEBUG, "EAP-SIM: Peer selected unsupported "
 343                            "version %d", attr->selected_version);
 344                 eap_sim_state(data, FAILURE);
 345                 return;
 346         }
 347
 348         if (attr->identity) {
 349                 free(sm->identity);
 350                 sm->identity = malloc(attr->identity_len);
 351                 if (sm->identity) {
 352                         memcpy(sm->identity, attr->identity,
 353                                attr->identity_len);
 354                         sm->identity_len = attr->identity_len;
 355                 }
 356         }
 357
 358         identity = NULL;
 359         identity_len = 0;
 360
 361         if (sm->identity && sm->identity_len > 0 &&
 362             sm->identity[0] == EAP_SIM_PERMANENT_PREFIX) {
 363                 identity = sm->identity;
 364                 identity_len = sm->identity_len;
 365         } else {
 366                 identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv,
 367                                                     sm->identity,
 368                                                     sm->identity_len,
 369                                                     &identity_len);
 370                 if (identity == NULL) {
 371                         data->reauth = eap_sim_db_get_reauth_entry(
 372                                 sm->eap_sim_db_priv, sm->identity,
 373                                 sm->identity_len);
 374                         if (data->reauth) {
 375                                 wpa_printf(MSG_DEBUG, "EAP-SIM: Using fast "
 376                                            "re-authentication");
 377                                 identity = data->reauth->identity;
 378                                 identity_len = data->reauth->identity_len;
 379                                 data->counter = data->reauth->counter;
 380                                 memcpy(data->mk, data->reauth->mk,
 381                                        EAP_SIM_MK_LEN);
 382                         }
 383                 }
 384         }
 385
 386         if (identity == NULL) {
 387                 wpa_printf(MSG_DEBUG, "EAP-SIM: Could not get proper permanent"
 388                            " user name");
 389                 eap_sim_state(data, FAILURE);
 390                 return;
 391         }
 392
 393         wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
 394                           identity, identity_len);
 395
 396         if (data->reauth) {
 397                 eap_sim_state(data, REAUTH);
 398                 return;
 399         }
 400
 401         data->counter = 0; /* reset re-auth counter since this is full auth */
 402         data->reauth = NULL;
 403
 404         data->num_chal = eap_sim_db_get_gsm_triplets(
 405                 sm->eap_sim_db_priv, identity, identity_len,
 406                 EAP_SIM_MAX_CHAL,
 407                 (u8 *) data->rand, (u8 *) data->kc, (u8 *) data->sres, sm);
 408         if (data->num_chal == EAP_SIM_DB_PENDING) {
 409                 wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication triplets "
 410                            "not yet available - pending request");
 411                 sm->method_pending = METHOD_PENDING_WAIT;
 412                 return;
 413         }
 414         if (data->num_chal < 2) {
 415                 wpa_printf(MSG_INFO, "EAP-SIM: Failed to get GSM "
 416                            "authentication triplets for the peer");
 417                 eap_sim_state(data, FAILURE);
 418                 return;
 419         }
 420
 421         wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity for MK derivation",
 422                           sm->identity, sm->identity_len);
 423
 424         memcpy(data->nonce_mt, attr->nonce_mt, EAP_SIM_NONCE_MT_LEN);
 425         WPA_PUT_BE16(ver_list, EAP_SIM_VERSION);
 426         eap_sim_derive_mk(sm->identity, sm->identity_len, attr->nonce_mt,
 427                           attr->selected_version, ver_list, sizeof(ver_list),
 428                           data->num_chal, (const u8 *) data->kc, data->mk);
 429         eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
 430                             data->emsk);
 431
 432         eap_sim_state(data, CHALLENGE);
 433 }
 434
 435
 436 static void eap_sim_process_challenge(struct eap_sm *sm,
 437                                       struct eap_sim_data *data,
 438                                       u8 *respData, size_t respDataLen,
 439                                       struct eap_sim_attrs *attr)
 440 {
 441         const u8 *identity;
 442         size_t identity_len;
 443
 444         if (attr->mac == NULL ||
 445             eap_sim_verify_mac(data->k_aut, respData, respDataLen, attr->mac,
 446                                (u8 *) data->sres,
 447                                data->num_chal * EAP_SIM_SRES_LEN)) {
 448                 wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
 449                            "did not include valid AT_MAC");
 450                 eap_sim_state(data, FAILURE);
 451                 return;
 452         }
 453
 454         wpa_printf(MSG_DEBUG, "EAP-SIM: Challenge response includes the "
 455                    "correct AT_MAC");
 456         eap_sim_state(data, SUCCESS);
 457
 458         identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv, sm->identity,
 459                                             sm->identity_len, &identity_len);
 460         if (identity == NULL) {
 461                 identity = sm->identity;
 462                 identity_len = sm->identity_len;
 463         }
 464
 465         if (data->next_pseudonym) {
 466                 eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
 467                                          identity_len,
 468                                          data->next_pseudonym);
 469                 data->next_pseudonym = NULL;
 470         }
 471         if (data->next_reauth_id) {
 472                 eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
 473                                       identity_len,
 474                                       data->next_reauth_id, data->counter + 1,
 475                                       data->mk);
 476                 data->next_reauth_id = NULL;
 477         }
 478 }
 479
 480
 481 static void eap_sim_process_reauth(struct eap_sm *sm,
 482                                    struct eap_sim_data *data,
 483                                    u8 *respData, size_t respDataLen,
 484                                    struct eap_sim_attrs *attr)
 485 {
 486         struct eap_sim_attrs eattr;
 487         u8 *decrypted = NULL;
 488         const u8 *identity, *id2;
 489         size_t identity_len, id2_len;
 490
 491         if (attr->mac == NULL ||
 492             eap_sim_verify_mac(data->k_aut, respData, respDataLen, attr->mac,
 493                                data->nonce_s, EAP_SIM_NONCE_S_LEN)) {
 494                 wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
 495                            "did not include valid AT_MAC");
 496                 goto fail;
 497         }
 498
 499         if (attr->encr_data == NULL || attr->iv == NULL) {
 500                 wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication "
 501                            "message did not include encrypted data");
 502                 goto fail;
 503         }
 504
 505         decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
 506                                        attr->encr_data_len, attr->iv, &eattr,
 507                                        0);
 508         if (decrypted == NULL) {
 509                 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted "
 510                            "data from reauthentication message");
 511                 goto fail;
 512         }
 513
 514         if (eattr.counter != data->counter) {
 515                 wpa_printf(MSG_WARNING, "EAP-SIM: Re-authentication message "
 516                            "used incorrect counter %u, expected %u",
 517                            eattr.counter, data->counter);
 518                 goto fail;
 519         }
 520         free(decrypted);
 521         decrypted = NULL;
 522
 523         wpa_printf(MSG_DEBUG, "EAP-SIM: Re-authentication response includes "
 524                    "the correct AT_MAC");
 525         eap_sim_state(data, SUCCESS);
 526
 527         if (data->reauth) {
 528                 identity = data->reauth->identity;
 529                 identity_len = data->reauth->identity_len;
 530         } else {
 531                 identity = sm->identity;
 532                 identity_len = sm->identity_len;
 533         }
 534
 535         id2 = eap_sim_db_get_permanent(sm->eap_sim_db_priv, identity,
 536                                        identity_len, &id2_len);
 537         if (id2) {
 538                 identity = id2;
 539                 identity_len = id2_len;
 540         }
 541
 542         if (data->next_pseudonym) {
 543                 eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
 544                                          identity_len, data->next_pseudonym);
 545                 data->next_pseudonym = NULL;
 546         }
 547         if (data->next_reauth_id) {
 548                 eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
 549                                       identity_len, data->next_reauth_id,
 550                                       data->counter + 1, data->mk);
 551                 data->next_reauth_id = NULL;
 552         } else {
 553                 eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
 554                 data->reauth = NULL;
 555         }
 556
 557         return;
 558
 559 fail:
 560         eap_sim_state(data, FAILURE);
 561         eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
 562         data->reauth = NULL;
 563         free(decrypted);
 564 }
 565
 566
 567 static void eap_sim_process_client_error(struct eap_sm *sm,
 568                                          struct eap_sim_data *data,
 569                                          u8 *respData, size_t respDataLen,
 570                                          struct eap_sim_attrs *attr)
 571 {
 572         wpa_printf(MSG_DEBUG, "EAP-SIM: Client reported error %d",
 573                    attr->client_error_code);
 574         eap_sim_state(data, FAILURE);
 575 }
 576
 577
 578 static void eap_sim_process(struct eap_sm *sm, void *priv,
 579                             u8 *respData, size_t respDataLen)
 580 {
 581         struct eap_sim_data *data = priv;
 582         struct eap_hdr *resp;
 583         u8 *pos, subtype;
 584         size_t len;
 585         struct eap_sim_attrs attr;
 586
 587         resp = (struct eap_hdr *) respData;
 588         pos = (u8 *) (resp + 1);
 589         subtype = pos[1];
 590         len = ntohs(resp->length);
 591         pos += 4;
 592
 593         if (eap_sim_parse_attr(pos, respData + len, &attr, 0, 0)) {
 594                 wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to parse attributes");
 595                 eap_sim_state(data, FAILURE);
 596                 return;
 597         }
 598
 599         if (subtype == EAP_SIM_SUBTYPE_CLIENT_ERROR) {
 600                 eap_sim_process_client_error(sm, data, respData, len, &attr);
 601                 return;
 602         }
 603
 604         switch (data->state) {
 605         case START:
 606                 eap_sim_process_start(sm, data, respData, len, &attr);
 607                 break;
 608         case CHALLENGE:
 609                 eap_sim_process_challenge(sm, data, respData, len, &attr);
 610                 break;
 611         case REAUTH:
 612                 eap_sim_process_reauth(sm, data, respData, len, &attr);
 613                 break;
 614         default:
 615                 wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown state %d in "
 616                            "process", data->state);
 617                 break;
 618         }
 619 }
 620
 621
 622 static Boolean eap_sim_isDone(struct eap_sm *sm, void *priv)
 623 {
 624         struct eap_sim_data *data = priv;
 625         return data->state == SUCCESS || data->state == FAILURE;
 626 }
 627
 628
 629 static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len)
 630 {
 631         struct eap_sim_data *data = priv;
 632         u8 *key;
 633
 634         if (data->state != SUCCESS)
 635                 return NULL;
 636
 637         key = malloc(EAP_SIM_KEYING_DATA_LEN);
 638         if (key == NULL)
 639                 return NULL;
 640         memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
 641         *len = EAP_SIM_KEYING_DATA_LEN;
 642         return key;
 643 }
 644
 645
 646 static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
 647 {
 648         struct eap_sim_data *data = priv;
 649         u8 *key;
 650
 651         if (data->state != SUCCESS)
 652                 return NULL;
 653
 654         key = malloc(EAP_EMSK_LEN);
 655         if (key == NULL)
 656                 return NULL;
 657         memcpy(key, data->emsk, EAP_EMSK_LEN);
 658         *len = EAP_EMSK_LEN;
 659         return key;
 660 }
 661
 662
 663 static Boolean eap_sim_isSuccess(struct eap_sm *sm, void *priv)
 664 {
 665         struct eap_sim_data *data = priv;
 666         return data->state == SUCCESS;
 667 }
 668
 669
 670 int eap_server_sim_register(void)
 671 {
 672         struct eap_method *eap;
 673         int ret;
 674
 675         eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
 676                                       EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM");
 677         if (eap == NULL)
 678                 return -1;
 679
 680         eap->init = eap_sim_init;
 681         eap->reset = eap_sim_reset;
 682         eap->buildReq = eap_sim_buildReq;
 683         eap->check = eap_sim_check;
 684         eap->process = eap_sim_process;
 685         eap->isDone = eap_sim_isDone;
 686         eap->getKey = eap_sim_getKey;
 687         eap->isSuccess = eap_sim_isSuccess;
 688         eap->get_emsk = eap_sim_get_emsk;
 689
 690         ret = eap_server_method_register(eap);
 691         if (ret)
 692                 eap_server_method_free(eap);
 693         return ret;
 694 }