1 /* 2 * EAP-WSC peer for Wi-Fi Protected Setup 3 * Copyright (c) 2007-2009, 2012, Jouni Malinen <j@w1.fi> 4 * 5 * This software may be distributed under the terms of the BSD license. 6 * See README for more details. 7 */ 8 9 #include "includes.h" 10 11 #include "common.h" 12 #include "uuid.h" 13 #include "eap_i.h" 14 #include "eap_common/eap_wsc_common.h" 15 #include "wps/wps.h" 16 #include "wps/wps_defs.h" 17 18 19 struct eap_wsc_data { 20 enum { WAIT_START, MESG, WAIT_FRAG_ACK, FAIL } state; 21 int registrar; 22 struct wpabuf *in_buf; 23 struct wpabuf *out_buf; 24 enum wsc_op_code in_op_code, out_op_code; 25 size_t out_used; 26 size_t fragment_size; 27 struct wps_data *wps; 28 struct wps_context *wps_ctx; 29 }; 30 31 32 static const char * eap_wsc_state_txt(int state) 33 { 34 switch (state) { 35 case WAIT_START: 36 return "WAIT_START"; 37 case MESG: 38 return "MESG"; 39 case WAIT_FRAG_ACK: 40 return "WAIT_FRAG_ACK"; 41 case FAIL: 42 return "FAIL"; 43 default: 44 return "?"; 45 } 46 } 47 48 49 static void eap_wsc_state(struct eap_wsc_data *data, int state) 50 { 51 wpa_printf(MSG_DEBUG, "EAP-WSC: %s -> %s", 52 eap_wsc_state_txt(data->state), 53 eap_wsc_state_txt(state)); 54 data->state = state; 55 } 56 57 58 static int eap_wsc_new_ap_settings(struct wps_credential *cred, 59 const char *params) 60 { 61 const char *pos, *end; 62 size_t len; 63 64 os_memset(cred, 0, sizeof(*cred)); 65 66 pos = os_strstr(params, "new_ssid="); 67 if (pos == NULL) 68 return 0; 69 pos += 9; 70 end = os_strchr(pos, ' '); 71 if (end == NULL) 72 len = os_strlen(pos); 73 else 74 len = end - pos; 75 if ((len & 1) || len > 2 * sizeof(cred->ssid) || 76 hexstr2bin(pos, cred->ssid, len / 2)) { 77 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_ssid"); 78 return -1; 79 } 80 cred->ssid_len = len / 2; 81 82 pos = os_strstr(params, "new_auth="); 83 if (pos == NULL) { 84 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_auth"); 85 return -1; 86 } 87 if (os_strncmp(pos + 9, "OPEN", 4) == 0) 88 cred->auth_type = WPS_AUTH_OPEN; 89 else if (os_strncmp(pos + 9, "WPAPSK", 6) == 0) 90 cred->auth_type = WPS_AUTH_WPAPSK; 91 else if (os_strncmp(pos + 9, "WPA2PSK", 7) == 0) 92 cred->auth_type = WPS_AUTH_WPA2PSK; 93 else { 94 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_auth"); 95 return -1; 96 } 97 98 pos = os_strstr(params, "new_encr="); 99 if (pos == NULL) { 100 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_encr"); 101 return -1; 102 } 103 if (os_strncmp(pos + 9, "NONE", 4) == 0) 104 cred->encr_type = WPS_ENCR_NONE; 105 #ifdef CONFIG_TESTING_OPTIONS 106 else if (os_strncmp(pos + 9, "WEP", 3) == 0) 107 cred->encr_type = WPS_ENCR_WEP; 108 #endif /* CONFIG_TESTING_OPTIONS */ 109 else if (os_strncmp(pos + 9, "TKIP", 4) == 0) 110 cred->encr_type = WPS_ENCR_TKIP; 111 else if (os_strncmp(pos + 9, "CCMP", 4) == 0) 112 cred->encr_type = WPS_ENCR_AES; 113 else { 114 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_encr"); 115 return -1; 116 } 117 118 pos = os_strstr(params, "new_key="); 119 if (pos == NULL) 120 return 0; 121 pos += 8; 122 end = os_strchr(pos, ' '); 123 if (end == NULL) 124 len = os_strlen(pos); 125 else 126 len = end - pos; 127 if ((len & 1) || len > 2 * sizeof(cred->key) || 128 hexstr2bin(pos, cred->key, len / 2)) { 129 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_key"); 130 return -1; 131 } 132 cred->key_len = len / 2; 133 134 return 1; 135 } 136 137 138 static void * eap_wsc_init(struct eap_sm *sm) 139 { 140 struct eap_wsc_data *data; 141 const u8 *identity; 142 size_t identity_len; 143 int registrar; 144 struct wps_config cfg; 145 const char *pos, *end; 146 const char *phase1; 147 struct wps_context *wps; 148 struct wps_credential new_ap_settings; 149 int res; 150 int nfc = 0; 151 u8 pkhash[WPS_OOB_PUBKEY_HASH_LEN]; 152 153 wps = sm->wps; 154 if (wps == NULL) { 155 wpa_printf(MSG_ERROR, "EAP-WSC: WPS context not available"); 156 return NULL; 157 } 158 159 identity = eap_get_config_identity(sm, &identity_len); 160 161 if (identity && identity_len == WSC_ID_REGISTRAR_LEN && 162 os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0) 163 registrar = 1; /* Supplicant is Registrar */ 164 else if (identity && identity_len == WSC_ID_ENROLLEE_LEN && 165 os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0) 166 registrar = 0; /* Supplicant is Enrollee */ 167 else { 168 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity", 169 identity, identity_len); 170 return NULL; 171 } 172 173 data = os_zalloc(sizeof(*data)); 174 if (data == NULL) 175 return NULL; 176 data->state = registrar ? MESG : WAIT_START; 177 data->registrar = registrar; 178 data->wps_ctx = wps; 179 180 os_memset(&cfg, 0, sizeof(cfg)); 181 cfg.wps = wps; 182 cfg.registrar = registrar; 183 184 phase1 = eap_get_config_phase1(sm); 185 if (phase1 == NULL) { 186 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not " 187 "set"); 188 os_free(data); 189 return NULL; 190 } 191 192 pos = os_strstr(phase1, "pin="); 193 if (pos) { 194 pos += 4; 195 cfg.pin = (const u8 *) pos; 196 while (*pos != '\0' && *pos != ' ') 197 pos++; 198 cfg.pin_len = pos - (const char *) cfg.pin; 199 if (cfg.pin_len == 6 && 200 os_strncmp((const char *) cfg.pin, "nfc-pw", 6) == 0) { 201 cfg.pin = NULL; 202 cfg.pin_len = 0; 203 nfc = 1; 204 } 205 } else { 206 pos = os_strstr(phase1, "pbc=1"); 207 if (pos) 208 cfg.pbc = 1; 209 } 210 211 pos = os_strstr(phase1, "dev_pw_id="); 212 if (pos) { 213 u16 id = atoi(pos + 10); 214 if (id == DEV_PW_NFC_CONNECTION_HANDOVER) 215 nfc = 1; 216 if (cfg.pin || id == DEV_PW_NFC_CONNECTION_HANDOVER) 217 cfg.dev_pw_id = id; 218 } 219 220 if (cfg.pin == NULL && !cfg.pbc && !nfc) { 221 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 " 222 "configuration data"); 223 os_free(data); 224 return NULL; 225 } 226 227 pos = os_strstr(phase1, " pkhash="); 228 if (pos) { 229 size_t len; 230 pos += 8; 231 end = os_strchr(pos, ' '); 232 if (end) 233 len = end - pos; 234 else 235 len = os_strlen(pos); 236 if (len != 2 * WPS_OOB_PUBKEY_HASH_LEN || 237 hexstr2bin(pos, pkhash, WPS_OOB_PUBKEY_HASH_LEN)) { 238 wpa_printf(MSG_INFO, "EAP-WSC: Invalid pkhash"); 239 os_free(data); 240 return NULL; 241 } 242 cfg.peer_pubkey_hash = pkhash; 243 } 244 245 res = eap_wsc_new_ap_settings(&new_ap_settings, phase1); 246 if (res < 0) { 247 os_free(data); 248 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to parse new AP " 249 "settings"); 250 return NULL; 251 } 252 if (res == 1) { 253 wpa_printf(MSG_DEBUG, "EAP-WSC: Provide new AP settings for " 254 "WPS"); 255 cfg.new_ap_settings = &new_ap_settings; 256 } 257 258 if (os_strstr(phase1, "multi_ap=1")) 259 cfg.multi_ap_backhaul_sta = 1; 260 261 data->wps = wps_init(&cfg); 262 if (data->wps == NULL) { 263 os_free(data); 264 wpa_printf(MSG_DEBUG, "EAP-WSC: wps_init failed"); 265 return NULL; 266 } 267 res = eap_get_config_fragment_size(sm); 268 if (res > 0) 269 data->fragment_size = res; 270 else 271 data->fragment_size = WSC_FRAGMENT_SIZE; 272 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u", 273 (unsigned int) data->fragment_size); 274 275 if (registrar && cfg.pin) { 276 wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL, 277 cfg.pin, cfg.pin_len, 0); 278 } 279 280 /* Use reduced client timeout for WPS to avoid long wait */ 281 if (sm->ClientTimeout > 30) 282 sm->ClientTimeout = 30; 283 284 return data; 285 } 286 287 288 static void eap_wsc_deinit(struct eap_sm *sm, void *priv) 289 { 290 struct eap_wsc_data *data = priv; 291 wpabuf_free(data->in_buf); 292 wpabuf_free(data->out_buf); 293 wps_deinit(data->wps); 294 os_free(data->wps_ctx->network_key); 295 data->wps_ctx->network_key = NULL; 296 os_free(data); 297 } 298 299 300 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data, 301 struct eap_method_ret *ret, u8 id) 302 { 303 struct wpabuf *resp; 304 u8 flags; 305 size_t send_len, plen; 306 307 ret->ignore = false; 308 wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response"); 309 ret->allowNotifications = true; 310 311 flags = 0; 312 send_len = wpabuf_len(data->out_buf) - data->out_used; 313 if (2 + send_len > data->fragment_size) { 314 send_len = data->fragment_size - 2; 315 flags |= WSC_FLAGS_MF; 316 if (data->out_used == 0) { 317 flags |= WSC_FLAGS_LF; 318 send_len -= 2; 319 } 320 } 321 plen = 2 + send_len; 322 if (flags & WSC_FLAGS_LF) 323 plen += 2; 324 resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen, 325 EAP_CODE_RESPONSE, id); 326 if (resp == NULL) 327 return NULL; 328 329 wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */ 330 wpabuf_put_u8(resp, flags); /* Flags */ 331 if (flags & WSC_FLAGS_LF) 332 wpabuf_put_be16(resp, wpabuf_len(data->out_buf)); 333 334 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used, 335 send_len); 336 data->out_used += send_len; 337 338 ret->methodState = METHOD_MAY_CONT; 339 ret->decision = DECISION_FAIL; 340 341 if (data->out_used == wpabuf_len(data->out_buf)) { 342 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes " 343 "(message sent completely)", 344 (unsigned long) send_len); 345 wpabuf_free(data->out_buf); 346 data->out_buf = NULL; 347 data->out_used = 0; 348 if ((data->state == FAIL && data->out_op_code == WSC_ACK) || 349 data->out_op_code == WSC_NACK || 350 data->out_op_code == WSC_Done) { 351 eap_wsc_state(data, FAIL); 352 ret->methodState = METHOD_DONE; 353 } else 354 eap_wsc_state(data, MESG); 355 } else { 356 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes " 357 "(%lu more to send)", (unsigned long) send_len, 358 (unsigned long) wpabuf_len(data->out_buf) - 359 data->out_used); 360 eap_wsc_state(data, WAIT_FRAG_ACK); 361 } 362 363 return resp; 364 } 365 366 367 static int eap_wsc_process_cont(struct eap_wsc_data *data, 368 const u8 *buf, size_t len, u8 op_code) 369 { 370 /* Process continuation of a pending message */ 371 if (op_code != data->in_op_code) { 372 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in " 373 "fragment (expected %d)", 374 op_code, data->in_op_code); 375 return -1; 376 } 377 378 if (len > wpabuf_tailroom(data->in_buf)) { 379 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow"); 380 eap_wsc_state(data, FAIL); 381 return -1; 382 } 383 384 wpabuf_put_data(data->in_buf, buf, len); 385 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting " 386 "for %lu bytes more", (unsigned long) len, 387 (unsigned long) wpabuf_tailroom(data->in_buf)); 388 389 return 0; 390 } 391 392 393 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data, 394 struct eap_method_ret *ret, 395 u8 id, u8 flags, u8 op_code, 396 u16 message_length, 397 const u8 *buf, size_t len) 398 { 399 /* Process a fragment that is not the last one of the message */ 400 if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) { 401 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a " 402 "fragmented packet"); 403 ret->ignore = true; 404 return NULL; 405 } 406 407 if (data->in_buf == NULL) { 408 /* First fragment of the message */ 409 data->in_buf = wpabuf_alloc(message_length); 410 if (data->in_buf == NULL) { 411 wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for " 412 "message"); 413 ret->ignore = true; 414 return NULL; 415 } 416 data->in_op_code = op_code; 417 wpabuf_put_data(data->in_buf, buf, len); 418 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first " 419 "fragment, waiting for %lu bytes more", 420 (unsigned long) len, 421 (unsigned long) wpabuf_tailroom(data->in_buf)); 422 } 423 424 return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE); 425 } 426 427 428 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv, 429 struct eap_method_ret *ret, 430 const struct wpabuf *reqData) 431 { 432 struct eap_wsc_data *data = priv; 433 const u8 *start, *pos, *end; 434 size_t len; 435 u8 op_code, flags, id; 436 u16 message_length = 0; 437 enum wps_process_res res; 438 struct wpabuf tmpbuf; 439 struct wpabuf *r; 440 441 pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData, 442 &len); 443 if (pos == NULL || len < 2) { 444 ret->ignore = true; 445 return NULL; 446 } 447 448 id = eap_get_id(reqData); 449 450 start = pos; 451 end = start + len; 452 453 op_code = *pos++; 454 flags = *pos++; 455 if (flags & WSC_FLAGS_LF) { 456 if (end - pos < 2) { 457 wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow"); 458 ret->ignore = true; 459 return NULL; 460 } 461 message_length = WPA_GET_BE16(pos); 462 pos += 2; 463 464 if (message_length < end - pos || message_length > 50000) { 465 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message " 466 "Length"); 467 ret->ignore = true; 468 return NULL; 469 } 470 } 471 472 wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d " 473 "Flags 0x%x Message Length %d", 474 op_code, flags, message_length); 475 476 if (data->state == WAIT_FRAG_ACK) { 477 if (op_code != WSC_FRAG_ACK) { 478 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d " 479 "in WAIT_FRAG_ACK state", op_code); 480 ret->ignore = true; 481 return NULL; 482 } 483 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged"); 484 eap_wsc_state(data, MESG); 485 return eap_wsc_build_msg(data, ret, id); 486 } 487 488 if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG && 489 op_code != WSC_Done && op_code != WSC_Start) { 490 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d", 491 op_code); 492 ret->ignore = true; 493 return NULL; 494 } 495 496 if (data->state == WAIT_START) { 497 if (op_code != WSC_Start) { 498 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d " 499 "in WAIT_START state", op_code); 500 ret->ignore = true; 501 return NULL; 502 } 503 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start"); 504 eap_wsc_state(data, MESG); 505 /* Start message has empty payload, skip processing */ 506 goto send_msg; 507 } else if (op_code == WSC_Start) { 508 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d", 509 op_code); 510 ret->ignore = true; 511 return NULL; 512 } 513 514 if (data->in_buf && 515 eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) { 516 ret->ignore = true; 517 return NULL; 518 } 519 520 if (flags & WSC_FLAGS_MF) { 521 return eap_wsc_process_fragment(data, ret, id, flags, op_code, 522 message_length, pos, 523 end - pos); 524 } 525 526 if (data->in_buf == NULL) { 527 /* Wrap unfragmented messages as wpabuf without extra copy */ 528 wpabuf_set(&tmpbuf, pos, end - pos); 529 data->in_buf = &tmpbuf; 530 } 531 532 res = wps_process_msg(data->wps, op_code, data->in_buf); 533 switch (res) { 534 case WPS_DONE: 535 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed " 536 "successfully - wait for EAP failure"); 537 eap_wsc_state(data, FAIL); 538 break; 539 case WPS_CONTINUE: 540 eap_wsc_state(data, MESG); 541 break; 542 case WPS_FAILURE: 543 case WPS_PENDING: 544 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed"); 545 eap_wsc_state(data, FAIL); 546 break; 547 } 548 549 if (data->in_buf != &tmpbuf) 550 wpabuf_free(data->in_buf); 551 data->in_buf = NULL; 552 553 send_msg: 554 if (data->out_buf == NULL) { 555 data->out_buf = wps_get_msg(data->wps, &data->out_op_code); 556 if (data->out_buf == NULL) { 557 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive " 558 "message from WPS"); 559 eap_wsc_state(data, FAIL); 560 ret->methodState = METHOD_DONE; 561 ret->decision = DECISION_FAIL; 562 return NULL; 563 } 564 data->out_used = 0; 565 } 566 567 eap_wsc_state(data, MESG); 568 r = eap_wsc_build_msg(data, ret, id); 569 if (data->state == FAIL && ret->methodState == METHOD_DONE) { 570 /* Use reduced client timeout for WPS to avoid long wait */ 571 if (sm->ClientTimeout > 2) 572 sm->ClientTimeout = 2; 573 } 574 return r; 575 } 576 577 578 int eap_peer_wsc_register(void) 579 { 580 struct eap_method *eap; 581 582 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION, 583 EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, 584 "WSC"); 585 if (eap == NULL) 586 return -1; 587 588 eap->init = eap_wsc_init; 589 eap->deinit = eap_wsc_deinit; 590 eap->process = eap_wsc_process; 591 592 return eap_peer_method_register(eap); 593 } 594