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