1 /* 2 * EAP peer method: EAP-SIM (RFC 4186) 3 * Copyright (c) 2004-2008, 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 "eap_peer/eap_i.h" 19 #include "eap_config.h" 20 #include "pcsc_funcs.h" 21 #include "eap_common/eap_sim_common.h" 22 #ifdef CONFIG_SIM_SIMULATOR 23 #include "hlr_auc_gw/milenage.h" 24 #endif /* CONFIG_SIM_SIMULATOR */ 25 26 27 struct eap_sim_data { 28 u8 *ver_list; 29 size_t ver_list_len; 30 int selected_version; 31 size_t min_num_chal, num_chal; 32 33 u8 kc[3][EAP_SIM_KC_LEN]; 34 u8 sres[3][EAP_SIM_SRES_LEN]; 35 u8 nonce_mt[EAP_SIM_NONCE_MT_LEN], nonce_s[EAP_SIM_NONCE_S_LEN]; 36 u8 mk[EAP_SIM_MK_LEN]; 37 u8 k_aut[EAP_SIM_K_AUT_LEN]; 38 u8 k_encr[EAP_SIM_K_ENCR_LEN]; 39 u8 msk[EAP_SIM_KEYING_DATA_LEN]; 40 u8 emsk[EAP_EMSK_LEN]; 41 u8 rand[3][GSM_RAND_LEN]; 42 43 int num_id_req, num_notification; 44 u8 *pseudonym; 45 size_t pseudonym_len; 46 u8 *reauth_id; 47 size_t reauth_id_len; 48 int reauth; 49 unsigned int counter, counter_too_small; 50 u8 *last_eap_identity; 51 size_t last_eap_identity_len; 52 enum { 53 CONTINUE, RESULT_SUCCESS, RESULT_FAILURE, SUCCESS, FAILURE 54 } state; 55 int result_ind, use_result_ind; 56 }; 57 58 59 #ifndef CONFIG_NO_STDOUT_DEBUG 60 static const char * eap_sim_state_txt(int state) 61 { 62 switch (state) { 63 case CONTINUE: 64 return "CONTINUE"; 65 case RESULT_SUCCESS: 66 return "RESULT_SUCCESS"; 67 case RESULT_FAILURE: 68 return "RESULT_FAILURE"; 69 case SUCCESS: 70 return "SUCCESS"; 71 case FAILURE: 72 return "FAILURE"; 73 default: 74 return "?"; 75 } 76 } 77 #endif /* CONFIG_NO_STDOUT_DEBUG */ 78 79 80 static void eap_sim_state(struct eap_sim_data *data, int state) 81 { 82 wpa_printf(MSG_DEBUG, "EAP-SIM: %s -> %s", 83 eap_sim_state_txt(data->state), 84 eap_sim_state_txt(state)); 85 data->state = state; 86 } 87 88 89 static void * eap_sim_init(struct eap_sm *sm) 90 { 91 struct eap_sim_data *data; 92 struct eap_peer_config *config = eap_get_config(sm); 93 94 data = os_zalloc(sizeof(*data)); 95 if (data == NULL) 96 return NULL; 97 98 if (os_get_random(data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) { 99 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to get random data " 100 "for NONCE_MT"); 101 os_free(data); 102 return NULL; 103 } 104 105 data->min_num_chal = 2; 106 if (config && config->phase1) { 107 char *pos = os_strstr(config->phase1, "sim_min_num_chal="); 108 if (pos) { 109 data->min_num_chal = atoi(pos + 17); 110 if (data->min_num_chal < 2 || data->min_num_chal > 3) { 111 wpa_printf(MSG_WARNING, "EAP-SIM: Invalid " 112 "sim_min_num_chal configuration " 113 "(%lu, expected 2 or 3)", 114 (unsigned long) data->min_num_chal); 115 os_free(data); 116 return NULL; 117 } 118 wpa_printf(MSG_DEBUG, "EAP-SIM: Set minimum number of " 119 "challenges to %lu", 120 (unsigned long) data->min_num_chal); 121 } 122 123 data->result_ind = os_strstr(config->phase1, "result_ind=1") != 124 NULL; 125 } 126 127 eap_sim_state(data, CONTINUE); 128 129 return data; 130 } 131 132 133 static void eap_sim_deinit(struct eap_sm *sm, void *priv) 134 { 135 struct eap_sim_data *data = priv; 136 if (data) { 137 os_free(data->ver_list); 138 os_free(data->pseudonym); 139 os_free(data->reauth_id); 140 os_free(data->last_eap_identity); 141 os_free(data); 142 } 143 } 144 145 146 static int eap_sim_gsm_auth(struct eap_sm *sm, struct eap_sim_data *data) 147 { 148 struct eap_peer_config *conf; 149 150 wpa_printf(MSG_DEBUG, "EAP-SIM: GSM authentication algorithm"); 151 152 conf = eap_get_config(sm); 153 if (conf == NULL) 154 return -1; 155 if (conf->pcsc) { 156 if (scard_gsm_auth(sm->scard_ctx, data->rand[0], 157 data->sres[0], data->kc[0]) || 158 scard_gsm_auth(sm->scard_ctx, data->rand[1], 159 data->sres[1], data->kc[1]) || 160 (data->num_chal > 2 && 161 scard_gsm_auth(sm->scard_ctx, data->rand[2], 162 data->sres[2], data->kc[2]))) { 163 wpa_printf(MSG_DEBUG, "EAP-SIM: GSM SIM " 164 "authentication could not be completed"); 165 return -1; 166 } 167 return 0; 168 } 169 170 #ifdef CONFIG_SIM_SIMULATOR 171 if (conf->password) { 172 u8 opc[16], k[16]; 173 const char *pos; 174 size_t i; 175 wpa_printf(MSG_DEBUG, "EAP-SIM: Use internal GSM-Milenage " 176 "implementation for authentication"); 177 if (conf->password_len < 65) { 178 wpa_printf(MSG_DEBUG, "EAP-SIM: invalid GSM-Milenage " 179 "password"); 180 return -1; 181 } 182 pos = (const char *) conf->password; 183 if (hexstr2bin(pos, k, 16)) 184 return -1; 185 pos += 32; 186 if (*pos != ':') 187 return -1; 188 pos++; 189 190 if (hexstr2bin(pos, opc, 16)) 191 return -1; 192 193 for (i = 0; i < data->num_chal; i++) { 194 if (gsm_milenage(opc, k, data->rand[i], 195 data->sres[i], data->kc[i])) { 196 wpa_printf(MSG_DEBUG, "EAP-SIM: " 197 "GSM-Milenage authentication " 198 "could not be completed"); 199 return -1; 200 } 201 wpa_hexdump(MSG_DEBUG, "EAP-SIM: RAND", 202 data->rand[i], GSM_RAND_LEN); 203 wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: SRES", 204 data->sres[i], EAP_SIM_SRES_LEN); 205 wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: Kc", 206 data->kc[i], EAP_SIM_KC_LEN); 207 } 208 return 0; 209 } 210 #endif /* CONFIG_SIM_SIMULATOR */ 211 212 #ifdef CONFIG_SIM_HARDCODED 213 /* These hardcoded Kc and SRES values are used for testing. RAND to 214 * KC/SREC mapping is very bogus as far as real authentication is 215 * concerned, but it is quite useful for cases where the AS is rotating 216 * the order of pre-configured values. */ 217 { 218 size_t i; 219 220 wpa_printf(MSG_DEBUG, "EAP-SIM: Use hardcoded Kc and SRES " 221 "values for testing"); 222 223 for (i = 0; i < data->num_chal; i++) { 224 if (data->rand[i][0] == 0xaa) { 225 os_memcpy(data->kc[i], 226 "\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7", 227 EAP_SIM_KC_LEN); 228 os_memcpy(data->sres[i], "\xd1\xd2\xd3\xd4", 229 EAP_SIM_SRES_LEN); 230 } else if (data->rand[i][0] == 0xbb) { 231 os_memcpy(data->kc[i], 232 "\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7", 233 EAP_SIM_KC_LEN); 234 os_memcpy(data->sres[i], "\xe1\xe2\xe3\xe4", 235 EAP_SIM_SRES_LEN); 236 } else { 237 os_memcpy(data->kc[i], 238 "\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7", 239 EAP_SIM_KC_LEN); 240 os_memcpy(data->sres[i], "\xf1\xf2\xf3\xf4", 241 EAP_SIM_SRES_LEN); 242 } 243 } 244 } 245 246 return 0; 247 248 #else /* CONFIG_SIM_HARDCODED */ 249 250 wpa_printf(MSG_DEBUG, "EAP-SIM: No GSM authentication algorithm " 251 "enabled"); 252 return -1; 253 254 #endif /* CONFIG_SIM_HARDCODED */ 255 } 256 257 258 static int eap_sim_supported_ver(int version) 259 { 260 return version == EAP_SIM_VERSION; 261 } 262 263 264 #define CLEAR_PSEUDONYM 0x01 265 #define CLEAR_REAUTH_ID 0x02 266 #define CLEAR_EAP_ID 0x04 267 268 static void eap_sim_clear_identities(struct eap_sim_data *data, int id) 269 { 270 wpa_printf(MSG_DEBUG, "EAP-SIM: forgetting old%s%s%s", 271 id & CLEAR_PSEUDONYM ? " pseudonym" : "", 272 id & CLEAR_REAUTH_ID ? " reauth_id" : "", 273 id & CLEAR_EAP_ID ? " eap_id" : ""); 274 if (id & CLEAR_PSEUDONYM) { 275 os_free(data->pseudonym); 276 data->pseudonym = NULL; 277 data->pseudonym_len = 0; 278 } 279 if (id & CLEAR_REAUTH_ID) { 280 os_free(data->reauth_id); 281 data->reauth_id = NULL; 282 data->reauth_id_len = 0; 283 } 284 if (id & CLEAR_EAP_ID) { 285 os_free(data->last_eap_identity); 286 data->last_eap_identity = NULL; 287 data->last_eap_identity_len = 0; 288 } 289 } 290 291 292 static int eap_sim_learn_ids(struct eap_sim_data *data, 293 struct eap_sim_attrs *attr) 294 { 295 if (attr->next_pseudonym) { 296 os_free(data->pseudonym); 297 data->pseudonym = os_malloc(attr->next_pseudonym_len); 298 if (data->pseudonym == NULL) { 299 wpa_printf(MSG_INFO, "EAP-SIM: (encr) No memory for " 300 "next pseudonym"); 301 return -1; 302 } 303 os_memcpy(data->pseudonym, attr->next_pseudonym, 304 attr->next_pseudonym_len); 305 data->pseudonym_len = attr->next_pseudonym_len; 306 wpa_hexdump_ascii(MSG_DEBUG, 307 "EAP-SIM: (encr) AT_NEXT_PSEUDONYM", 308 data->pseudonym, 309 data->pseudonym_len); 310 } 311 312 if (attr->next_reauth_id) { 313 os_free(data->reauth_id); 314 data->reauth_id = os_malloc(attr->next_reauth_id_len); 315 if (data->reauth_id == NULL) { 316 wpa_printf(MSG_INFO, "EAP-SIM: (encr) No memory for " 317 "next reauth_id"); 318 return -1; 319 } 320 os_memcpy(data->reauth_id, attr->next_reauth_id, 321 attr->next_reauth_id_len); 322 data->reauth_id_len = attr->next_reauth_id_len; 323 wpa_hexdump_ascii(MSG_DEBUG, 324 "EAP-SIM: (encr) AT_NEXT_REAUTH_ID", 325 data->reauth_id, 326 data->reauth_id_len); 327 } 328 329 return 0; 330 } 331 332 333 static struct wpabuf * eap_sim_client_error(struct eap_sim_data *data, u8 id, 334 int err) 335 { 336 struct eap_sim_msg *msg; 337 338 eap_sim_state(data, FAILURE); 339 data->num_id_req = 0; 340 data->num_notification = 0; 341 342 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM, 343 EAP_SIM_SUBTYPE_CLIENT_ERROR); 344 eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0); 345 return eap_sim_msg_finish(msg, NULL, NULL, 0); 346 } 347 348 349 static struct wpabuf * eap_sim_response_start(struct eap_sm *sm, 350 struct eap_sim_data *data, u8 id, 351 enum eap_sim_id_req id_req) 352 { 353 const u8 *identity = NULL; 354 size_t identity_len = 0; 355 struct eap_sim_msg *msg; 356 357 data->reauth = 0; 358 if (id_req == ANY_ID && data->reauth_id) { 359 identity = data->reauth_id; 360 identity_len = data->reauth_id_len; 361 data->reauth = 1; 362 } else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) && 363 data->pseudonym) { 364 identity = data->pseudonym; 365 identity_len = data->pseudonym_len; 366 eap_sim_clear_identities(data, CLEAR_REAUTH_ID); 367 } else if (id_req != NO_ID_REQ) { 368 identity = eap_get_config_identity(sm, &identity_len); 369 if (identity) { 370 eap_sim_clear_identities(data, CLEAR_PSEUDONYM | 371 CLEAR_REAUTH_ID); 372 } 373 } 374 if (id_req != NO_ID_REQ) 375 eap_sim_clear_identities(data, CLEAR_EAP_ID); 376 377 wpa_printf(MSG_DEBUG, "Generating EAP-SIM Start (id=%d)", id); 378 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, 379 EAP_TYPE_SIM, EAP_SIM_SUBTYPE_START); 380 if (!data->reauth) { 381 wpa_hexdump(MSG_DEBUG, " AT_NONCE_MT", 382 data->nonce_mt, EAP_SIM_NONCE_MT_LEN); 383 eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_MT, 0, 384 data->nonce_mt, EAP_SIM_NONCE_MT_LEN); 385 wpa_printf(MSG_DEBUG, " AT_SELECTED_VERSION %d", 386 data->selected_version); 387 eap_sim_msg_add(msg, EAP_SIM_AT_SELECTED_VERSION, 388 data->selected_version, NULL, 0); 389 } 390 391 if (identity) { 392 wpa_hexdump_ascii(MSG_DEBUG, " AT_IDENTITY", 393 identity, identity_len); 394 eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len, 395 identity, identity_len); 396 } 397 398 return eap_sim_msg_finish(msg, NULL, NULL, 0); 399 } 400 401 402 static struct wpabuf * eap_sim_response_challenge(struct eap_sim_data *data, 403 u8 id) 404 { 405 struct eap_sim_msg *msg; 406 407 wpa_printf(MSG_DEBUG, "Generating EAP-SIM Challenge (id=%d)", id); 408 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM, 409 EAP_SIM_SUBTYPE_CHALLENGE); 410 if (data->use_result_ind) { 411 wpa_printf(MSG_DEBUG, " AT_RESULT_IND"); 412 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0); 413 } 414 wpa_printf(MSG_DEBUG, " AT_MAC"); 415 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); 416 return eap_sim_msg_finish(msg, data->k_aut, (u8 *) data->sres, 417 data->num_chal * EAP_SIM_SRES_LEN); 418 } 419 420 421 static struct wpabuf * eap_sim_response_reauth(struct eap_sim_data *data, 422 u8 id, int counter_too_small) 423 { 424 struct eap_sim_msg *msg; 425 unsigned int counter; 426 427 wpa_printf(MSG_DEBUG, "Generating EAP-SIM Reauthentication (id=%d)", 428 id); 429 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, EAP_TYPE_SIM, 430 EAP_SIM_SUBTYPE_REAUTHENTICATION); 431 wpa_printf(MSG_DEBUG, " AT_IV"); 432 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA"); 433 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA); 434 435 if (counter_too_small) { 436 wpa_printf(MSG_DEBUG, " *AT_COUNTER_TOO_SMALL"); 437 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0); 438 counter = data->counter_too_small; 439 } else 440 counter = data->counter; 441 442 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", counter); 443 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0); 444 445 if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) { 446 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt " 447 "AT_ENCR_DATA"); 448 eap_sim_msg_free(msg); 449 return NULL; 450 } 451 if (data->use_result_ind) { 452 wpa_printf(MSG_DEBUG, " AT_RESULT_IND"); 453 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0); 454 } 455 wpa_printf(MSG_DEBUG, " AT_MAC"); 456 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); 457 return eap_sim_msg_finish(msg, data->k_aut, data->nonce_s, 458 EAP_SIM_NONCE_S_LEN); 459 } 460 461 462 static struct wpabuf * eap_sim_response_notification(struct eap_sim_data *data, 463 u8 id, u16 notification) 464 { 465 struct eap_sim_msg *msg; 466 u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL; 467 468 wpa_printf(MSG_DEBUG, "Generating EAP-SIM Notification (id=%d)", id); 469 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, 470 EAP_TYPE_SIM, EAP_SIM_SUBTYPE_NOTIFICATION); 471 wpa_printf(MSG_DEBUG, " AT_NOTIFICATION"); 472 eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, notification, NULL, 0); 473 if (k_aut && data->reauth) { 474 wpa_printf(MSG_DEBUG, " AT_IV"); 475 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA"); 476 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, 477 EAP_SIM_AT_ENCR_DATA); 478 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", data->counter); 479 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter, 480 NULL, 0); 481 if (eap_sim_msg_add_encr_end(msg, data->k_encr, 482 EAP_SIM_AT_PADDING)) { 483 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt " 484 "AT_ENCR_DATA"); 485 eap_sim_msg_free(msg); 486 return NULL; 487 } 488 } 489 if (k_aut) { 490 wpa_printf(MSG_DEBUG, " AT_MAC"); 491 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); 492 } 493 return eap_sim_msg_finish(msg, k_aut, (u8 *) "", 0); 494 } 495 496 497 static struct wpabuf * eap_sim_process_start(struct eap_sm *sm, 498 struct eap_sim_data *data, u8 id, 499 struct eap_sim_attrs *attr) 500 { 501 int selected_version = -1, id_error; 502 size_t i; 503 u8 *pos; 504 505 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Start"); 506 if (attr->version_list == NULL) { 507 wpa_printf(MSG_INFO, "EAP-SIM: No AT_VERSION_LIST in " 508 "SIM/Start"); 509 return eap_sim_client_error(data, id, 510 EAP_SIM_UNSUPPORTED_VERSION); 511 } 512 513 os_free(data->ver_list); 514 data->ver_list = os_malloc(attr->version_list_len); 515 if (data->ver_list == NULL) { 516 wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to allocate " 517 "memory for version list"); 518 return eap_sim_client_error(data, id, 519 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 520 } 521 os_memcpy(data->ver_list, attr->version_list, attr->version_list_len); 522 data->ver_list_len = attr->version_list_len; 523 pos = data->ver_list; 524 for (i = 0; i < data->ver_list_len / 2; i++) { 525 int ver = pos[0] * 256 + pos[1]; 526 pos += 2; 527 if (eap_sim_supported_ver(ver)) { 528 selected_version = ver; 529 break; 530 } 531 } 532 if (selected_version < 0) { 533 wpa_printf(MSG_INFO, "EAP-SIM: Could not find a supported " 534 "version"); 535 return eap_sim_client_error(data, id, 536 EAP_SIM_UNSUPPORTED_VERSION); 537 } 538 wpa_printf(MSG_DEBUG, "EAP-SIM: Selected Version %d", 539 selected_version); 540 data->selected_version = selected_version; 541 542 id_error = 0; 543 switch (attr->id_req) { 544 case NO_ID_REQ: 545 break; 546 case ANY_ID: 547 if (data->num_id_req > 0) 548 id_error++; 549 data->num_id_req++; 550 break; 551 case FULLAUTH_ID: 552 if (data->num_id_req > 1) 553 id_error++; 554 data->num_id_req++; 555 break; 556 case PERMANENT_ID: 557 if (data->num_id_req > 2) 558 id_error++; 559 data->num_id_req++; 560 break; 561 } 562 if (id_error) { 563 wpa_printf(MSG_INFO, "EAP-SIM: Too many ID requests " 564 "used within one authentication"); 565 return eap_sim_client_error(data, id, 566 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 567 } 568 569 return eap_sim_response_start(sm, data, id, attr->id_req); 570 } 571 572 573 static struct wpabuf * eap_sim_process_challenge(struct eap_sm *sm, 574 struct eap_sim_data *data, 575 u8 id, 576 const struct wpabuf *reqData, 577 struct eap_sim_attrs *attr) 578 { 579 const u8 *identity; 580 size_t identity_len; 581 struct eap_sim_attrs eattr; 582 583 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge"); 584 data->reauth = 0; 585 if (!attr->mac || !attr->rand) { 586 wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " 587 "did not include%s%s", 588 !attr->mac ? " AT_MAC" : "", 589 !attr->rand ? " AT_RAND" : ""); 590 return eap_sim_client_error(data, id, 591 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 592 } 593 594 wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges", 595 (unsigned long) attr->num_chal); 596 if (attr->num_chal < data->min_num_chal) { 597 wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of " 598 "challenges (%lu)", (unsigned long) attr->num_chal); 599 return eap_sim_client_error(data, id, 600 EAP_SIM_INSUFFICIENT_NUM_OF_CHAL); 601 } 602 if (attr->num_chal > 3) { 603 wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges " 604 "(%lu)", (unsigned long) attr->num_chal); 605 return eap_sim_client_error(data, id, 606 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 607 } 608 609 /* Verify that RANDs are different */ 610 if (os_memcmp(attr->rand, attr->rand + GSM_RAND_LEN, 611 GSM_RAND_LEN) == 0 || 612 (attr->num_chal > 2 && 613 (os_memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN, 614 GSM_RAND_LEN) == 0 || 615 os_memcmp(attr->rand + GSM_RAND_LEN, 616 attr->rand + 2 * GSM_RAND_LEN, 617 GSM_RAND_LEN) == 0))) { 618 wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times"); 619 return eap_sim_client_error(data, id, 620 EAP_SIM_RAND_NOT_FRESH); 621 } 622 623 os_memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN); 624 data->num_chal = attr->num_chal; 625 626 if (eap_sim_gsm_auth(sm, data)) { 627 wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed"); 628 return eap_sim_client_error(data, id, 629 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 630 } 631 if (data->last_eap_identity) { 632 identity = data->last_eap_identity; 633 identity_len = data->last_eap_identity_len; 634 } else if (data->pseudonym) { 635 identity = data->pseudonym; 636 identity_len = data->pseudonym_len; 637 } else 638 identity = eap_get_config_identity(sm, &identity_len); 639 wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK " 640 "derivation", identity, identity_len); 641 eap_sim_derive_mk(identity, identity_len, data->nonce_mt, 642 data->selected_version, data->ver_list, 643 data->ver_list_len, data->num_chal, 644 (const u8 *) data->kc, data->mk); 645 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk, 646 data->emsk); 647 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, data->nonce_mt, 648 EAP_SIM_NONCE_MT_LEN)) { 649 wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " 650 "used invalid AT_MAC"); 651 return eap_sim_client_error(data, id, 652 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 653 } 654 655 /* Old reauthentication and pseudonym identities must not be used 656 * anymore. In other words, if no new identities are received, full 657 * authentication will be used on next reauthentication. */ 658 eap_sim_clear_identities(data, CLEAR_PSEUDONYM | CLEAR_REAUTH_ID | 659 CLEAR_EAP_ID); 660 661 if (attr->encr_data) { 662 u8 *decrypted; 663 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 664 attr->encr_data_len, attr->iv, 665 &eattr, 0); 666 if (decrypted == NULL) { 667 return eap_sim_client_error( 668 data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); 669 } 670 eap_sim_learn_ids(data, &eattr); 671 os_free(decrypted); 672 } 673 674 if (data->result_ind && attr->result_ind) 675 data->use_result_ind = 1; 676 677 if (data->state != FAILURE && data->state != RESULT_FAILURE) { 678 eap_sim_state(data, data->use_result_ind ? 679 RESULT_SUCCESS : SUCCESS); 680 } 681 682 data->num_id_req = 0; 683 data->num_notification = 0; 684 /* RFC 4186 specifies that counter is initialized to one after 685 * fullauth, but initializing it to zero makes it easier to implement 686 * reauth verification. */ 687 data->counter = 0; 688 return eap_sim_response_challenge(data, id); 689 } 690 691 692 static int eap_sim_process_notification_reauth(struct eap_sim_data *data, 693 struct eap_sim_attrs *attr) 694 { 695 struct eap_sim_attrs eattr; 696 u8 *decrypted; 697 698 if (attr->encr_data == NULL || attr->iv == NULL) { 699 wpa_printf(MSG_WARNING, "EAP-SIM: Notification message after " 700 "reauth did not include encrypted data"); 701 return -1; 702 } 703 704 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 705 attr->encr_data_len, attr->iv, &eattr, 706 0); 707 if (decrypted == NULL) { 708 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted " 709 "data from notification message"); 710 return -1; 711 } 712 713 if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) { 714 wpa_printf(MSG_WARNING, "EAP-SIM: Counter in notification " 715 "message does not match with counter in reauth " 716 "message"); 717 os_free(decrypted); 718 return -1; 719 } 720 721 os_free(decrypted); 722 return 0; 723 } 724 725 726 static int eap_sim_process_notification_auth(struct eap_sim_data *data, 727 const struct wpabuf *reqData, 728 struct eap_sim_attrs *attr) 729 { 730 if (attr->mac == NULL) { 731 wpa_printf(MSG_INFO, "EAP-SIM: no AT_MAC in after_auth " 732 "Notification message"); 733 return -1; 734 } 735 736 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0)) 737 { 738 wpa_printf(MSG_WARNING, "EAP-SIM: Notification message " 739 "used invalid AT_MAC"); 740 return -1; 741 } 742 743 if (data->reauth && 744 eap_sim_process_notification_reauth(data, attr)) { 745 wpa_printf(MSG_WARNING, "EAP-SIM: Invalid notification " 746 "message after reauth"); 747 return -1; 748 } 749 750 return 0; 751 } 752 753 754 static struct wpabuf * eap_sim_process_notification( 755 struct eap_sm *sm, struct eap_sim_data *data, u8 id, 756 const struct wpabuf *reqData, struct eap_sim_attrs *attr) 757 { 758 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Notification"); 759 if (data->num_notification > 0) { 760 wpa_printf(MSG_INFO, "EAP-SIM: too many notification " 761 "rounds (only one allowed)"); 762 return eap_sim_client_error(data, id, 763 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 764 } 765 data->num_notification++; 766 if (attr->notification == -1) { 767 wpa_printf(MSG_INFO, "EAP-SIM: no AT_NOTIFICATION in " 768 "Notification message"); 769 return eap_sim_client_error(data, id, 770 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 771 } 772 773 if ((attr->notification & 0x4000) == 0 && 774 eap_sim_process_notification_auth(data, reqData, attr)) { 775 return eap_sim_client_error(data, id, 776 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 777 } 778 779 eap_sim_report_notification(sm->msg_ctx, attr->notification, 0); 780 if (attr->notification >= 0 && attr->notification < 32768) { 781 eap_sim_state(data, FAILURE); 782 } else if (attr->notification == EAP_SIM_SUCCESS && 783 data->state == RESULT_SUCCESS) 784 eap_sim_state(data, SUCCESS); 785 return eap_sim_response_notification(data, id, attr->notification); 786 } 787 788 789 static struct wpabuf * eap_sim_process_reauthentication( 790 struct eap_sm *sm, struct eap_sim_data *data, u8 id, 791 const struct wpabuf *reqData, struct eap_sim_attrs *attr) 792 { 793 struct eap_sim_attrs eattr; 794 u8 *decrypted; 795 796 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Reauthentication"); 797 798 if (data->reauth_id == NULL) { 799 wpa_printf(MSG_WARNING, "EAP-SIM: Server is trying " 800 "reauthentication, but no reauth_id available"); 801 return eap_sim_client_error(data, id, 802 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 803 } 804 805 data->reauth = 1; 806 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0)) 807 { 808 wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication " 809 "did not have valid AT_MAC"); 810 return eap_sim_client_error(data, id, 811 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 812 } 813 814 if (attr->encr_data == NULL || attr->iv == NULL) { 815 wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication " 816 "message did not include encrypted data"); 817 return eap_sim_client_error(data, id, 818 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 819 } 820 821 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 822 attr->encr_data_len, attr->iv, &eattr, 823 0); 824 if (decrypted == NULL) { 825 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted " 826 "data from reauthentication message"); 827 return eap_sim_client_error(data, id, 828 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 829 } 830 831 if (eattr.nonce_s == NULL || eattr.counter < 0) { 832 wpa_printf(MSG_INFO, "EAP-SIM: (encr) No%s%s in reauth packet", 833 !eattr.nonce_s ? " AT_NONCE_S" : "", 834 eattr.counter < 0 ? " AT_COUNTER" : ""); 835 os_free(decrypted); 836 return eap_sim_client_error(data, id, 837 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 838 } 839 840 if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) { 841 wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid counter " 842 "(%d <= %d)", eattr.counter, data->counter); 843 data->counter_too_small = eattr.counter; 844 /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current 845 * reauth_id must not be used to start a new reauthentication. 846 * However, since it was used in the last EAP-Response-Identity 847 * packet, it has to saved for the following fullauth to be 848 * used in MK derivation. */ 849 os_free(data->last_eap_identity); 850 data->last_eap_identity = data->reauth_id; 851 data->last_eap_identity_len = data->reauth_id_len; 852 data->reauth_id = NULL; 853 data->reauth_id_len = 0; 854 os_free(decrypted); 855 return eap_sim_response_reauth(data, id, 1); 856 } 857 data->counter = eattr.counter; 858 859 os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN); 860 wpa_hexdump(MSG_DEBUG, "EAP-SIM: (encr) AT_NONCE_S", 861 data->nonce_s, EAP_SIM_NONCE_S_LEN); 862 863 eap_sim_derive_keys_reauth(data->counter, 864 data->reauth_id, data->reauth_id_len, 865 data->nonce_s, data->mk, data->msk, 866 data->emsk); 867 eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); 868 eap_sim_learn_ids(data, &eattr); 869 870 if (data->result_ind && attr->result_ind) 871 data->use_result_ind = 1; 872 873 if (data->state != FAILURE && data->state != RESULT_FAILURE) { 874 eap_sim_state(data, data->use_result_ind ? 875 RESULT_SUCCESS : SUCCESS); 876 } 877 878 data->num_id_req = 0; 879 data->num_notification = 0; 880 if (data->counter > EAP_SIM_MAX_FAST_REAUTHS) { 881 wpa_printf(MSG_DEBUG, "EAP-SIM: Maximum number of " 882 "fast reauths performed - force fullauth"); 883 eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); 884 } 885 os_free(decrypted); 886 return eap_sim_response_reauth(data, id, 0); 887 } 888 889 890 static struct wpabuf * eap_sim_process(struct eap_sm *sm, void *priv, 891 struct eap_method_ret *ret, 892 const struct wpabuf *reqData) 893 { 894 struct eap_sim_data *data = priv; 895 const struct eap_hdr *req; 896 u8 subtype, id; 897 struct wpabuf *res; 898 const u8 *pos; 899 struct eap_sim_attrs attr; 900 size_t len; 901 902 wpa_hexdump_buf(MSG_DEBUG, "EAP-SIM: EAP data", reqData); 903 if (eap_get_config_identity(sm, &len) == NULL) { 904 wpa_printf(MSG_INFO, "EAP-SIM: Identity not configured"); 905 eap_sm_request_identity(sm); 906 ret->ignore = TRUE; 907 return NULL; 908 } 909 910 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, reqData, &len); 911 if (pos == NULL || len < 1) { 912 ret->ignore = TRUE; 913 return NULL; 914 } 915 req = wpabuf_head(reqData); 916 id = req->identifier; 917 len = be_to_host16(req->length); 918 919 ret->ignore = FALSE; 920 ret->methodState = METHOD_MAY_CONT; 921 ret->decision = DECISION_FAIL; 922 ret->allowNotifications = TRUE; 923 924 subtype = *pos++; 925 wpa_printf(MSG_DEBUG, "EAP-SIM: Subtype=%d", subtype); 926 pos += 2; /* Reserved */ 927 928 if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr, 0, 929 0)) { 930 res = eap_sim_client_error(data, id, 931 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 932 goto done; 933 } 934 935 switch (subtype) { 936 case EAP_SIM_SUBTYPE_START: 937 res = eap_sim_process_start(sm, data, id, &attr); 938 break; 939 case EAP_SIM_SUBTYPE_CHALLENGE: 940 res = eap_sim_process_challenge(sm, data, id, reqData, &attr); 941 break; 942 case EAP_SIM_SUBTYPE_NOTIFICATION: 943 res = eap_sim_process_notification(sm, data, id, reqData, 944 &attr); 945 break; 946 case EAP_SIM_SUBTYPE_REAUTHENTICATION: 947 res = eap_sim_process_reauthentication(sm, data, id, reqData, 948 &attr); 949 break; 950 case EAP_SIM_SUBTYPE_CLIENT_ERROR: 951 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Client-Error"); 952 res = eap_sim_client_error(data, id, 953 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 954 break; 955 default: 956 wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown subtype=%d", subtype); 957 res = eap_sim_client_error(data, id, 958 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 959 break; 960 } 961 962 done: 963 if (data->state == FAILURE) { 964 ret->decision = DECISION_FAIL; 965 ret->methodState = METHOD_DONE; 966 } else if (data->state == SUCCESS) { 967 ret->decision = data->use_result_ind ? 968 DECISION_UNCOND_SUCC : DECISION_COND_SUCC; 969 ret->methodState = data->use_result_ind ? 970 METHOD_DONE : METHOD_MAY_CONT; 971 } else if (data->state == RESULT_FAILURE) 972 ret->methodState = METHOD_CONT; 973 else if (data->state == RESULT_SUCCESS) 974 ret->methodState = METHOD_CONT; 975 976 if (ret->methodState == METHOD_DONE) { 977 ret->allowNotifications = FALSE; 978 } 979 980 return res; 981 } 982 983 984 static Boolean eap_sim_has_reauth_data(struct eap_sm *sm, void *priv) 985 { 986 struct eap_sim_data *data = priv; 987 return data->pseudonym || data->reauth_id; 988 } 989 990 991 static void eap_sim_deinit_for_reauth(struct eap_sm *sm, void *priv) 992 { 993 struct eap_sim_data *data = priv; 994 eap_sim_clear_identities(data, CLEAR_EAP_ID); 995 data->use_result_ind = 0; 996 } 997 998 999 static void * eap_sim_init_for_reauth(struct eap_sm *sm, void *priv) 1000 { 1001 struct eap_sim_data *data = priv; 1002 if (os_get_random(data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) { 1003 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to get random data " 1004 "for NONCE_MT"); 1005 os_free(data); 1006 return NULL; 1007 } 1008 data->num_id_req = 0; 1009 data->num_notification = 0; 1010 eap_sim_state(data, CONTINUE); 1011 return priv; 1012 } 1013 1014 1015 static const u8 * eap_sim_get_identity(struct eap_sm *sm, void *priv, 1016 size_t *len) 1017 { 1018 struct eap_sim_data *data = priv; 1019 1020 if (data->reauth_id) { 1021 *len = data->reauth_id_len; 1022 return data->reauth_id; 1023 } 1024 1025 if (data->pseudonym) { 1026 *len = data->pseudonym_len; 1027 return data->pseudonym; 1028 } 1029 1030 return NULL; 1031 } 1032 1033 1034 static Boolean eap_sim_isKeyAvailable(struct eap_sm *sm, void *priv) 1035 { 1036 struct eap_sim_data *data = priv; 1037 return data->state == SUCCESS; 1038 } 1039 1040 1041 static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len) 1042 { 1043 struct eap_sim_data *data = priv; 1044 u8 *key; 1045 1046 if (data->state != SUCCESS) 1047 return NULL; 1048 1049 key = os_malloc(EAP_SIM_KEYING_DATA_LEN); 1050 if (key == NULL) 1051 return NULL; 1052 1053 *len = EAP_SIM_KEYING_DATA_LEN; 1054 os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN); 1055 1056 return key; 1057 } 1058 1059 1060 static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len) 1061 { 1062 struct eap_sim_data *data = priv; 1063 u8 *key; 1064 1065 if (data->state != SUCCESS) 1066 return NULL; 1067 1068 key = os_malloc(EAP_EMSK_LEN); 1069 if (key == NULL) 1070 return NULL; 1071 1072 *len = EAP_EMSK_LEN; 1073 os_memcpy(key, data->emsk, EAP_EMSK_LEN); 1074 1075 return key; 1076 } 1077 1078 1079 int eap_peer_sim_register(void) 1080 { 1081 struct eap_method *eap; 1082 int ret; 1083 1084 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, 1085 EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM"); 1086 if (eap == NULL) 1087 return -1; 1088 1089 eap->init = eap_sim_init; 1090 eap->deinit = eap_sim_deinit; 1091 eap->process = eap_sim_process; 1092 eap->isKeyAvailable = eap_sim_isKeyAvailable; 1093 eap->getKey = eap_sim_getKey; 1094 eap->has_reauth_data = eap_sim_has_reauth_data; 1095 eap->deinit_for_reauth = eap_sim_deinit_for_reauth; 1096 eap->init_for_reauth = eap_sim_init_for_reauth; 1097 eap->get_identity = eap_sim_get_identity; 1098 eap->get_emsk = eap_sim_get_emsk; 1099 1100 ret = eap_peer_method_register(eap); 1101 if (ret) 1102 eap_peer_method_free(eap); 1103 return ret; 1104 } 1105