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 "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 if (k_aut && data->reauth) { 472 wpa_printf(MSG_DEBUG, " AT_IV"); 473 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA"); 474 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, 475 EAP_SIM_AT_ENCR_DATA); 476 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", data->counter); 477 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter, 478 NULL, 0); 479 if (eap_sim_msg_add_encr_end(msg, data->k_encr, 480 EAP_SIM_AT_PADDING)) { 481 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to encrypt " 482 "AT_ENCR_DATA"); 483 eap_sim_msg_free(msg); 484 return NULL; 485 } 486 } 487 if (k_aut) { 488 wpa_printf(MSG_DEBUG, " AT_MAC"); 489 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); 490 } 491 return eap_sim_msg_finish(msg, k_aut, (u8 *) "", 0); 492 } 493 494 495 static struct wpabuf * eap_sim_process_start(struct eap_sm *sm, 496 struct eap_sim_data *data, u8 id, 497 struct eap_sim_attrs *attr) 498 { 499 int selected_version = -1, id_error; 500 size_t i; 501 u8 *pos; 502 503 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Start"); 504 if (attr->version_list == NULL) { 505 wpa_printf(MSG_INFO, "EAP-SIM: No AT_VERSION_LIST in " 506 "SIM/Start"); 507 return eap_sim_client_error(data, id, 508 EAP_SIM_UNSUPPORTED_VERSION); 509 } 510 511 os_free(data->ver_list); 512 data->ver_list = os_malloc(attr->version_list_len); 513 if (data->ver_list == NULL) { 514 wpa_printf(MSG_DEBUG, "EAP-SIM: Failed to allocate " 515 "memory for version list"); 516 return eap_sim_client_error(data, id, 517 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 518 } 519 os_memcpy(data->ver_list, attr->version_list, attr->version_list_len); 520 data->ver_list_len = attr->version_list_len; 521 pos = data->ver_list; 522 for (i = 0; i < data->ver_list_len / 2; i++) { 523 int ver = pos[0] * 256 + pos[1]; 524 pos += 2; 525 if (eap_sim_supported_ver(ver)) { 526 selected_version = ver; 527 break; 528 } 529 } 530 if (selected_version < 0) { 531 wpa_printf(MSG_INFO, "EAP-SIM: Could not find a supported " 532 "version"); 533 return eap_sim_client_error(data, id, 534 EAP_SIM_UNSUPPORTED_VERSION); 535 } 536 wpa_printf(MSG_DEBUG, "EAP-SIM: Selected Version %d", 537 selected_version); 538 data->selected_version = selected_version; 539 540 id_error = 0; 541 switch (attr->id_req) { 542 case NO_ID_REQ: 543 break; 544 case ANY_ID: 545 if (data->num_id_req > 0) 546 id_error++; 547 data->num_id_req++; 548 break; 549 case FULLAUTH_ID: 550 if (data->num_id_req > 1) 551 id_error++; 552 data->num_id_req++; 553 break; 554 case PERMANENT_ID: 555 if (data->num_id_req > 2) 556 id_error++; 557 data->num_id_req++; 558 break; 559 } 560 if (id_error) { 561 wpa_printf(MSG_INFO, "EAP-SIM: Too many ID requests " 562 "used within one authentication"); 563 return eap_sim_client_error(data, id, 564 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 565 } 566 567 return eap_sim_response_start(sm, data, id, attr->id_req); 568 } 569 570 571 static struct wpabuf * eap_sim_process_challenge(struct eap_sm *sm, 572 struct eap_sim_data *data, 573 u8 id, 574 const struct wpabuf *reqData, 575 struct eap_sim_attrs *attr) 576 { 577 const u8 *identity; 578 size_t identity_len; 579 struct eap_sim_attrs eattr; 580 581 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge"); 582 data->reauth = 0; 583 if (!attr->mac || !attr->rand) { 584 wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " 585 "did not include%s%s", 586 !attr->mac ? " AT_MAC" : "", 587 !attr->rand ? " AT_RAND" : ""); 588 return eap_sim_client_error(data, id, 589 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 590 } 591 592 wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges", 593 (unsigned long) attr->num_chal); 594 if (attr->num_chal < data->min_num_chal) { 595 wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of " 596 "challenges (%lu)", (unsigned long) attr->num_chal); 597 return eap_sim_client_error(data, id, 598 EAP_SIM_INSUFFICIENT_NUM_OF_CHAL); 599 } 600 if (attr->num_chal > 3) { 601 wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges " 602 "(%lu)", (unsigned long) attr->num_chal); 603 return eap_sim_client_error(data, id, 604 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 605 } 606 607 /* Verify that RANDs are different */ 608 if (os_memcmp(attr->rand, attr->rand + GSM_RAND_LEN, 609 GSM_RAND_LEN) == 0 || 610 (attr->num_chal > 2 && 611 (os_memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN, 612 GSM_RAND_LEN) == 0 || 613 os_memcmp(attr->rand + GSM_RAND_LEN, 614 attr->rand + 2 * GSM_RAND_LEN, 615 GSM_RAND_LEN) == 0))) { 616 wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times"); 617 return eap_sim_client_error(data, id, 618 EAP_SIM_RAND_NOT_FRESH); 619 } 620 621 os_memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN); 622 data->num_chal = attr->num_chal; 623 624 if (eap_sim_gsm_auth(sm, data)) { 625 wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed"); 626 return eap_sim_client_error(data, id, 627 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 628 } 629 if (data->last_eap_identity) { 630 identity = data->last_eap_identity; 631 identity_len = data->last_eap_identity_len; 632 } else if (data->pseudonym) { 633 identity = data->pseudonym; 634 identity_len = data->pseudonym_len; 635 } else 636 identity = eap_get_config_identity(sm, &identity_len); 637 wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK " 638 "derivation", identity, identity_len); 639 eap_sim_derive_mk(identity, identity_len, data->nonce_mt, 640 data->selected_version, data->ver_list, 641 data->ver_list_len, data->num_chal, 642 (const u8 *) data->kc, data->mk); 643 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk, 644 data->emsk); 645 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, data->nonce_mt, 646 EAP_SIM_NONCE_MT_LEN)) { 647 wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " 648 "used invalid AT_MAC"); 649 return eap_sim_client_error(data, id, 650 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 651 } 652 653 /* Old reauthentication and pseudonym identities must not be used 654 * anymore. In other words, if no new identities are received, full 655 * authentication will be used on next reauthentication. */ 656 eap_sim_clear_identities(data, CLEAR_PSEUDONYM | CLEAR_REAUTH_ID | 657 CLEAR_EAP_ID); 658 659 if (attr->encr_data) { 660 u8 *decrypted; 661 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 662 attr->encr_data_len, attr->iv, 663 &eattr, 0); 664 if (decrypted == NULL) { 665 return eap_sim_client_error( 666 data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); 667 } 668 eap_sim_learn_ids(data, &eattr); 669 os_free(decrypted); 670 } 671 672 if (data->result_ind && attr->result_ind) 673 data->use_result_ind = 1; 674 675 if (data->state != FAILURE && data->state != RESULT_FAILURE) { 676 eap_sim_state(data, data->use_result_ind ? 677 RESULT_SUCCESS : SUCCESS); 678 } 679 680 data->num_id_req = 0; 681 data->num_notification = 0; 682 /* RFC 4186 specifies that counter is initialized to one after 683 * fullauth, but initializing it to zero makes it easier to implement 684 * reauth verification. */ 685 data->counter = 0; 686 return eap_sim_response_challenge(data, id); 687 } 688 689 690 static int eap_sim_process_notification_reauth(struct eap_sim_data *data, 691 struct eap_sim_attrs *attr) 692 { 693 struct eap_sim_attrs eattr; 694 u8 *decrypted; 695 696 if (attr->encr_data == NULL || attr->iv == NULL) { 697 wpa_printf(MSG_WARNING, "EAP-SIM: Notification message after " 698 "reauth did not include encrypted data"); 699 return -1; 700 } 701 702 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 703 attr->encr_data_len, attr->iv, &eattr, 704 0); 705 if (decrypted == NULL) { 706 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted " 707 "data from notification message"); 708 return -1; 709 } 710 711 if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) { 712 wpa_printf(MSG_WARNING, "EAP-SIM: Counter in notification " 713 "message does not match with counter in reauth " 714 "message"); 715 os_free(decrypted); 716 return -1; 717 } 718 719 os_free(decrypted); 720 return 0; 721 } 722 723 724 static int eap_sim_process_notification_auth(struct eap_sim_data *data, 725 const struct wpabuf *reqData, 726 struct eap_sim_attrs *attr) 727 { 728 if (attr->mac == NULL) { 729 wpa_printf(MSG_INFO, "EAP-SIM: no AT_MAC in after_auth " 730 "Notification message"); 731 return -1; 732 } 733 734 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0)) 735 { 736 wpa_printf(MSG_WARNING, "EAP-SIM: Notification message " 737 "used invalid AT_MAC"); 738 return -1; 739 } 740 741 if (data->reauth && 742 eap_sim_process_notification_reauth(data, attr)) { 743 wpa_printf(MSG_WARNING, "EAP-SIM: Invalid notification " 744 "message after reauth"); 745 return -1; 746 } 747 748 return 0; 749 } 750 751 752 static struct wpabuf * eap_sim_process_notification( 753 struct eap_sm *sm, struct eap_sim_data *data, u8 id, 754 const struct wpabuf *reqData, struct eap_sim_attrs *attr) 755 { 756 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Notification"); 757 if (data->num_notification > 0) { 758 wpa_printf(MSG_INFO, "EAP-SIM: too many notification " 759 "rounds (only one allowed)"); 760 return eap_sim_client_error(data, id, 761 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 762 } 763 data->num_notification++; 764 if (attr->notification == -1) { 765 wpa_printf(MSG_INFO, "EAP-SIM: no AT_NOTIFICATION in " 766 "Notification message"); 767 return eap_sim_client_error(data, id, 768 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 769 } 770 771 if ((attr->notification & 0x4000) == 0 && 772 eap_sim_process_notification_auth(data, reqData, attr)) { 773 return eap_sim_client_error(data, id, 774 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 775 } 776 777 eap_sim_report_notification(sm->msg_ctx, attr->notification, 0); 778 if (attr->notification >= 0 && attr->notification < 32768) { 779 eap_sim_state(data, FAILURE); 780 } else if (attr->notification == EAP_SIM_SUCCESS && 781 data->state == RESULT_SUCCESS) 782 eap_sim_state(data, SUCCESS); 783 return eap_sim_response_notification(data, id, attr->notification); 784 } 785 786 787 static struct wpabuf * eap_sim_process_reauthentication( 788 struct eap_sm *sm, struct eap_sim_data *data, u8 id, 789 const struct wpabuf *reqData, struct eap_sim_attrs *attr) 790 { 791 struct eap_sim_attrs eattr; 792 u8 *decrypted; 793 794 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Reauthentication"); 795 796 if (data->reauth_id == NULL) { 797 wpa_printf(MSG_WARNING, "EAP-SIM: Server is trying " 798 "reauthentication, but no reauth_id available"); 799 return eap_sim_client_error(data, id, 800 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 801 } 802 803 data->reauth = 1; 804 if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, (u8 *) "", 0)) 805 { 806 wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication " 807 "did not have valid AT_MAC"); 808 return eap_sim_client_error(data, id, 809 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 810 } 811 812 if (attr->encr_data == NULL || attr->iv == NULL) { 813 wpa_printf(MSG_WARNING, "EAP-SIM: Reauthentication " 814 "message did not include encrypted data"); 815 return eap_sim_client_error(data, id, 816 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 817 } 818 819 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, 820 attr->encr_data_len, attr->iv, &eattr, 821 0); 822 if (decrypted == NULL) { 823 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to parse encrypted " 824 "data from reauthentication message"); 825 return eap_sim_client_error(data, id, 826 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 827 } 828 829 if (eattr.nonce_s == NULL || eattr.counter < 0) { 830 wpa_printf(MSG_INFO, "EAP-SIM: (encr) No%s%s in reauth packet", 831 !eattr.nonce_s ? " AT_NONCE_S" : "", 832 eattr.counter < 0 ? " AT_COUNTER" : ""); 833 os_free(decrypted); 834 return eap_sim_client_error(data, id, 835 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 836 } 837 838 if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) { 839 wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid counter " 840 "(%d <= %d)", eattr.counter, data->counter); 841 data->counter_too_small = eattr.counter; 842 /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current 843 * reauth_id must not be used to start a new reauthentication. 844 * However, since it was used in the last EAP-Response-Identity 845 * packet, it has to saved for the following fullauth to be 846 * used in MK derivation. */ 847 os_free(data->last_eap_identity); 848 data->last_eap_identity = data->reauth_id; 849 data->last_eap_identity_len = data->reauth_id_len; 850 data->reauth_id = NULL; 851 data->reauth_id_len = 0; 852 os_free(decrypted); 853 return eap_sim_response_reauth(data, id, 1); 854 } 855 data->counter = eattr.counter; 856 857 os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN); 858 wpa_hexdump(MSG_DEBUG, "EAP-SIM: (encr) AT_NONCE_S", 859 data->nonce_s, EAP_SIM_NONCE_S_LEN); 860 861 eap_sim_derive_keys_reauth(data->counter, 862 data->reauth_id, data->reauth_id_len, 863 data->nonce_s, data->mk, data->msk, 864 data->emsk); 865 eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); 866 eap_sim_learn_ids(data, &eattr); 867 868 if (data->result_ind && attr->result_ind) 869 data->use_result_ind = 1; 870 871 if (data->state != FAILURE && data->state != RESULT_FAILURE) { 872 eap_sim_state(data, data->use_result_ind ? 873 RESULT_SUCCESS : SUCCESS); 874 } 875 876 data->num_id_req = 0; 877 data->num_notification = 0; 878 if (data->counter > EAP_SIM_MAX_FAST_REAUTHS) { 879 wpa_printf(MSG_DEBUG, "EAP-SIM: Maximum number of " 880 "fast reauths performed - force fullauth"); 881 eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); 882 } 883 os_free(decrypted); 884 return eap_sim_response_reauth(data, id, 0); 885 } 886 887 888 static struct wpabuf * eap_sim_process(struct eap_sm *sm, void *priv, 889 struct eap_method_ret *ret, 890 const struct wpabuf *reqData) 891 { 892 struct eap_sim_data *data = priv; 893 const struct eap_hdr *req; 894 u8 subtype, id; 895 struct wpabuf *res; 896 const u8 *pos; 897 struct eap_sim_attrs attr; 898 size_t len; 899 900 wpa_hexdump_buf(MSG_DEBUG, "EAP-SIM: EAP data", reqData); 901 if (eap_get_config_identity(sm, &len) == NULL) { 902 wpa_printf(MSG_INFO, "EAP-SIM: Identity not configured"); 903 eap_sm_request_identity(sm); 904 ret->ignore = TRUE; 905 return NULL; 906 } 907 908 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SIM, reqData, &len); 909 if (pos == NULL || len < 1) { 910 ret->ignore = TRUE; 911 return NULL; 912 } 913 req = wpabuf_head(reqData); 914 id = req->identifier; 915 len = be_to_host16(req->length); 916 917 ret->ignore = FALSE; 918 ret->methodState = METHOD_MAY_CONT; 919 ret->decision = DECISION_FAIL; 920 ret->allowNotifications = TRUE; 921 922 subtype = *pos++; 923 wpa_printf(MSG_DEBUG, "EAP-SIM: Subtype=%d", subtype); 924 pos += 2; /* Reserved */ 925 926 if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr, 0, 927 0)) { 928 res = eap_sim_client_error(data, id, 929 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 930 goto done; 931 } 932 933 switch (subtype) { 934 case EAP_SIM_SUBTYPE_START: 935 res = eap_sim_process_start(sm, data, id, &attr); 936 break; 937 case EAP_SIM_SUBTYPE_CHALLENGE: 938 res = eap_sim_process_challenge(sm, data, id, reqData, &attr); 939 break; 940 case EAP_SIM_SUBTYPE_NOTIFICATION: 941 res = eap_sim_process_notification(sm, data, id, reqData, 942 &attr); 943 break; 944 case EAP_SIM_SUBTYPE_REAUTHENTICATION: 945 res = eap_sim_process_reauthentication(sm, data, id, reqData, 946 &attr); 947 break; 948 case EAP_SIM_SUBTYPE_CLIENT_ERROR: 949 wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Client-Error"); 950 res = eap_sim_client_error(data, id, 951 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 952 break; 953 default: 954 wpa_printf(MSG_DEBUG, "EAP-SIM: Unknown subtype=%d", subtype); 955 res = eap_sim_client_error(data, id, 956 EAP_SIM_UNABLE_TO_PROCESS_PACKET); 957 break; 958 } 959 960 done: 961 if (data->state == FAILURE) { 962 ret->decision = DECISION_FAIL; 963 ret->methodState = METHOD_DONE; 964 } else if (data->state == SUCCESS) { 965 ret->decision = data->use_result_ind ? 966 DECISION_UNCOND_SUCC : DECISION_COND_SUCC; 967 ret->methodState = data->use_result_ind ? 968 METHOD_DONE : METHOD_MAY_CONT; 969 } else if (data->state == RESULT_FAILURE) 970 ret->methodState = METHOD_CONT; 971 else if (data->state == RESULT_SUCCESS) 972 ret->methodState = METHOD_CONT; 973 974 if (ret->methodState == METHOD_DONE) { 975 ret->allowNotifications = FALSE; 976 } 977 978 return res; 979 } 980 981 982 static Boolean eap_sim_has_reauth_data(struct eap_sm *sm, void *priv) 983 { 984 struct eap_sim_data *data = priv; 985 return data->pseudonym || data->reauth_id; 986 } 987 988 989 static void eap_sim_deinit_for_reauth(struct eap_sm *sm, void *priv) 990 { 991 struct eap_sim_data *data = priv; 992 eap_sim_clear_identities(data, CLEAR_EAP_ID); 993 data->use_result_ind = 0; 994 } 995 996 997 static void * eap_sim_init_for_reauth(struct eap_sm *sm, void *priv) 998 { 999 struct eap_sim_data *data = priv; 1000 if (os_get_random(data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) { 1001 wpa_printf(MSG_WARNING, "EAP-SIM: Failed to get random data " 1002 "for NONCE_MT"); 1003 os_free(data); 1004 return NULL; 1005 } 1006 data->num_id_req = 0; 1007 data->num_notification = 0; 1008 eap_sim_state(data, CONTINUE); 1009 return priv; 1010 } 1011 1012 1013 static const u8 * eap_sim_get_identity(struct eap_sm *sm, void *priv, 1014 size_t *len) 1015 { 1016 struct eap_sim_data *data = priv; 1017 1018 if (data->reauth_id) { 1019 *len = data->reauth_id_len; 1020 return data->reauth_id; 1021 } 1022 1023 if (data->pseudonym) { 1024 *len = data->pseudonym_len; 1025 return data->pseudonym; 1026 } 1027 1028 return NULL; 1029 } 1030 1031 1032 static Boolean eap_sim_isKeyAvailable(struct eap_sm *sm, void *priv) 1033 { 1034 struct eap_sim_data *data = priv; 1035 return data->state == SUCCESS; 1036 } 1037 1038 1039 static u8 * eap_sim_getKey(struct eap_sm *sm, void *priv, size_t *len) 1040 { 1041 struct eap_sim_data *data = priv; 1042 u8 *key; 1043 1044 if (data->state != SUCCESS) 1045 return NULL; 1046 1047 key = os_malloc(EAP_SIM_KEYING_DATA_LEN); 1048 if (key == NULL) 1049 return NULL; 1050 1051 *len = EAP_SIM_KEYING_DATA_LEN; 1052 os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN); 1053 1054 return key; 1055 } 1056 1057 1058 static u8 * eap_sim_get_emsk(struct eap_sm *sm, void *priv, size_t *len) 1059 { 1060 struct eap_sim_data *data = priv; 1061 u8 *key; 1062 1063 if (data->state != SUCCESS) 1064 return NULL; 1065 1066 key = os_malloc(EAP_EMSK_LEN); 1067 if (key == NULL) 1068 return NULL; 1069 1070 *len = EAP_EMSK_LEN; 1071 os_memcpy(key, data->emsk, EAP_EMSK_LEN); 1072 1073 return key; 1074 } 1075 1076 1077 int eap_peer_sim_register(void) 1078 { 1079 struct eap_method *eap; 1080 int ret; 1081 1082 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, 1083 EAP_VENDOR_IETF, EAP_TYPE_SIM, "SIM"); 1084 if (eap == NULL) 1085 return -1; 1086 1087 eap->init = eap_sim_init; 1088 eap->deinit = eap_sim_deinit; 1089 eap->process = eap_sim_process; 1090 eap->isKeyAvailable = eap_sim_isKeyAvailable; 1091 eap->getKey = eap_sim_getKey; 1092 eap->has_reauth_data = eap_sim_has_reauth_data; 1093 eap->deinit_for_reauth = eap_sim_deinit_for_reauth; 1094 eap->init_for_reauth = eap_sim_init_for_reauth; 1095 eap->get_identity = eap_sim_get_identity; 1096 eap->get_emsk = eap_sim_get_emsk; 1097 1098 ret = eap_peer_method_register(eap); 1099 if (ret) 1100 eap_peer_method_free(eap); 1101 return ret; 1102 } 1103
