1 /* 2 * Wi-Fi Protected Setup - attribute parsing 3 * Copyright (c) 2008, Jouni Malinen <j (at) 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 "wps_defs.h" 13 #include "wps_attr_parse.h" 14 15 #ifndef CONFIG_WPS_STRICT 16 #define WPS_WORKAROUNDS 17 #endif /* CONFIG_WPS_STRICT */ 18 19 20 static int wps_set_vendor_ext_wfa_subelem(struct wps_parse_attr *attr, 21 u8 id, u8 len, const u8 *pos) 22 { 23 wpa_printf(MSG_EXCESSIVE, "WPS: WFA subelement id=%u len=%u", 24 id, len); 25 switch (id) { 26 case WFA_ELEM_VERSION2: 27 if (len != 1) { 28 wpa_printf(MSG_DEBUG, "WPS: Invalid Version2 length " 29 "%u", len); 30 return -1; 31 } 32 attr->version2 = pos; 33 break; 34 case WFA_ELEM_AUTHORIZEDMACS: 35 attr->authorized_macs = pos; 36 attr->authorized_macs_len = len; 37 break; 38 case WFA_ELEM_NETWORK_KEY_SHAREABLE: 39 if (len != 1) { 40 wpa_printf(MSG_DEBUG, "WPS: Invalid Network Key " 41 "Shareable length %u", len); 42 return -1; 43 } 44 attr->network_key_shareable = pos; 45 break; 46 case WFA_ELEM_REQUEST_TO_ENROLL: 47 if (len != 1) { 48 wpa_printf(MSG_DEBUG, "WPS: Invalid Request to Enroll " 49 "length %u", len); 50 return -1; 51 } 52 attr->request_to_enroll = pos; 53 break; 54 case WFA_ELEM_SETTINGS_DELAY_TIME: 55 if (len != 1) { 56 wpa_printf(MSG_DEBUG, "WPS: Invalid Settings Delay " 57 "Time length %u", len); 58 return -1; 59 } 60 attr->settings_delay_time = pos; 61 break; 62 case WFA_ELEM_REGISTRAR_CONFIGURATION_METHODS: 63 if (len != 2) { 64 wpa_printf(MSG_DEBUG, "WPS: Invalid Registrar Configuration Methods length %u", 65 len); 66 return -1; 67 } 68 attr->registrar_configuration_methods = pos; 69 break; 70 default: 71 wpa_printf(MSG_MSGDUMP, "WPS: Skipped unknown WFA Vendor " 72 "Extension subelement %u", id); 73 break; 74 } 75 76 return 0; 77 } 78 79 80 static int wps_parse_vendor_ext_wfa(struct wps_parse_attr *attr, const u8 *pos, 81 u16 len) 82 { 83 const u8 *end = pos + len; 84 u8 id, elen; 85 86 while (end - pos >= 2) { 87 id = *pos++; 88 elen = *pos++; 89 if (elen > end - pos) 90 break; 91 if (wps_set_vendor_ext_wfa_subelem(attr, id, elen, pos) < 0) 92 return -1; 93 pos += elen; 94 } 95 96 return 0; 97 } 98 99 100 static int wps_parse_vendor_ext(struct wps_parse_attr *attr, const u8 *pos, 101 u16 len) 102 { 103 u32 vendor_id; 104 105 if (len < 3) { 106 wpa_printf(MSG_DEBUG, "WPS: Skip invalid Vendor Extension"); 107 return 0; 108 } 109 110 vendor_id = WPA_GET_BE24(pos); 111 switch (vendor_id) { 112 case WPS_VENDOR_ID_WFA: 113 return wps_parse_vendor_ext_wfa(attr, pos + 3, len - 3); 114 } 115 116 /* Handle unknown vendor extensions */ 117 118 wpa_printf(MSG_MSGDUMP, "WPS: Unknown Vendor Extension (Vendor ID %u)", 119 vendor_id); 120 121 if (len > WPS_MAX_VENDOR_EXT_LEN) { 122 wpa_printf(MSG_DEBUG, "WPS: Too long Vendor Extension (%u)", 123 len); 124 return -1; 125 } 126 127 if (attr->num_vendor_ext >= MAX_WPS_PARSE_VENDOR_EXT) { 128 wpa_printf(MSG_DEBUG, "WPS: Skipped Vendor Extension " 129 "attribute (max %d vendor extensions)", 130 MAX_WPS_PARSE_VENDOR_EXT); 131 return -1; 132 } 133 attr->vendor_ext[attr->num_vendor_ext] = pos; 134 attr->vendor_ext_len[attr->num_vendor_ext] = len; 135 attr->num_vendor_ext++; 136 137 return 0; 138 } 139 140 141 static int wps_set_attr(struct wps_parse_attr *attr, u16 type, 142 const u8 *pos, u16 len) 143 { 144 switch (type) { 145 case ATTR_VERSION: 146 if (len != 1) { 147 wpa_printf(MSG_DEBUG, "WPS: Invalid Version length %u", 148 len); 149 return -1; 150 } 151 attr->version = pos; 152 break; 153 case ATTR_MSG_TYPE: 154 if (len != 1) { 155 wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type " 156 "length %u", len); 157 return -1; 158 } 159 attr->msg_type = pos; 160 break; 161 case ATTR_ENROLLEE_NONCE: 162 if (len != WPS_NONCE_LEN) { 163 wpa_printf(MSG_DEBUG, "WPS: Invalid Enrollee Nonce " 164 "length %u", len); 165 return -1; 166 } 167 attr->enrollee_nonce = pos; 168 break; 169 case ATTR_REGISTRAR_NONCE: 170 if (len != WPS_NONCE_LEN) { 171 wpa_printf(MSG_DEBUG, "WPS: Invalid Registrar Nonce " 172 "length %u", len); 173 return -1; 174 } 175 attr->registrar_nonce = pos; 176 break; 177 case ATTR_UUID_E: 178 if (len != WPS_UUID_LEN) { 179 wpa_printf(MSG_DEBUG, "WPS: Invalid UUID-E length %u", 180 len); 181 return -1; 182 } 183 attr->uuid_e = pos; 184 break; 185 case ATTR_UUID_R: 186 if (len != WPS_UUID_LEN) { 187 wpa_printf(MSG_DEBUG, "WPS: Invalid UUID-R length %u", 188 len); 189 return -1; 190 } 191 attr->uuid_r = pos; 192 break; 193 case ATTR_AUTH_TYPE_FLAGS: 194 if (len != 2) { 195 wpa_printf(MSG_DEBUG, "WPS: Invalid Authentication " 196 "Type Flags length %u", len); 197 return -1; 198 } 199 attr->auth_type_flags = pos; 200 break; 201 case ATTR_ENCR_TYPE_FLAGS: 202 if (len != 2) { 203 wpa_printf(MSG_DEBUG, "WPS: Invalid Encryption Type " 204 "Flags length %u", len); 205 return -1; 206 } 207 attr->encr_type_flags = pos; 208 break; 209 case ATTR_CONN_TYPE_FLAGS: 210 if (len != 1) { 211 wpa_printf(MSG_DEBUG, "WPS: Invalid Connection Type " 212 "Flags length %u", len); 213 return -1; 214 } 215 attr->conn_type_flags = pos; 216 break; 217 case ATTR_CONFIG_METHODS: 218 if (len != 2) { 219 wpa_printf(MSG_DEBUG, "WPS: Invalid Config Methods " 220 "length %u", len); 221 return -1; 222 } 223 attr->config_methods = pos; 224 break; 225 case ATTR_SELECTED_REGISTRAR_CONFIG_METHODS: 226 if (len != 2) { 227 wpa_printf(MSG_DEBUG, "WPS: Invalid Selected " 228 "Registrar Config Methods length %u", len); 229 return -1; 230 } 231 attr->sel_reg_config_methods = pos; 232 break; 233 case ATTR_PRIMARY_DEV_TYPE: 234 if (len != WPS_DEV_TYPE_LEN) { 235 wpa_printf(MSG_DEBUG, "WPS: Invalid Primary Device " 236 "Type length %u", len); 237 return -1; 238 } 239 attr->primary_dev_type = pos; 240 break; 241 case ATTR_RF_BANDS: 242 if (len != 1) { 243 wpa_printf(MSG_DEBUG, "WPS: Invalid RF Bands length " 244 "%u", len); 245 return -1; 246 } 247 attr->rf_bands = pos; 248 break; 249 case ATTR_ASSOC_STATE: 250 if (len != 2) { 251 wpa_printf(MSG_DEBUG, "WPS: Invalid Association State " 252 "length %u", len); 253 return -1; 254 } 255 attr->assoc_state = pos; 256 break; 257 case ATTR_CONFIG_ERROR: 258 if (len != 2) { 259 wpa_printf(MSG_DEBUG, "WPS: Invalid Configuration " 260 "Error length %u", len); 261 return -1; 262 } 263 attr->config_error = pos; 264 break; 265 case ATTR_DEV_PASSWORD_ID: 266 if (len != 2) { 267 wpa_printf(MSG_DEBUG, "WPS: Invalid Device Password " 268 "ID length %u", len); 269 return -1; 270 } 271 attr->dev_password_id = pos; 272 break; 273 case ATTR_OOB_DEVICE_PASSWORD: 274 if (len < WPS_OOB_PUBKEY_HASH_LEN + 2 || 275 len > WPS_OOB_PUBKEY_HASH_LEN + 2 + 276 WPS_OOB_DEVICE_PASSWORD_LEN || 277 (len < WPS_OOB_PUBKEY_HASH_LEN + 2 + 278 WPS_OOB_DEVICE_PASSWORD_MIN_LEN && 279 WPA_GET_BE16(pos + WPS_OOB_PUBKEY_HASH_LEN) != 280 DEV_PW_NFC_CONNECTION_HANDOVER)) { 281 wpa_printf(MSG_DEBUG, "WPS: Invalid OOB Device " 282 "Password length %u", len); 283 return -1; 284 } 285 attr->oob_dev_password = pos; 286 attr->oob_dev_password_len = len; 287 break; 288 case ATTR_OS_VERSION: 289 if (len != 4) { 290 wpa_printf(MSG_DEBUG, "WPS: Invalid OS Version length " 291 "%u", len); 292 return -1; 293 } 294 attr->os_version = pos; 295 break; 296 case ATTR_WPS_STATE: 297 if (len != 1) { 298 wpa_printf(MSG_DEBUG, "WPS: Invalid Wi-Fi Protected " 299 "Setup State length %u", len); 300 return -1; 301 } 302 attr->wps_state = pos; 303 break; 304 case ATTR_AUTHENTICATOR: 305 if (len != WPS_AUTHENTICATOR_LEN) { 306 wpa_printf(MSG_DEBUG, "WPS: Invalid Authenticator " 307 "length %u", len); 308 return -1; 309 } 310 attr->authenticator = pos; 311 break; 312 case ATTR_R_HASH1: 313 if (len != WPS_HASH_LEN) { 314 wpa_printf(MSG_DEBUG, "WPS: Invalid R-Hash1 length %u", 315 len); 316 return -1; 317 } 318 attr->r_hash1 = pos; 319 break; 320 case ATTR_R_HASH2: 321 if (len != WPS_HASH_LEN) { 322 wpa_printf(MSG_DEBUG, "WPS: Invalid R-Hash2 length %u", 323 len); 324 return -1; 325 } 326 attr->r_hash2 = pos; 327 break; 328 case ATTR_E_HASH1: 329 if (len != WPS_HASH_LEN) { 330 wpa_printf(MSG_DEBUG, "WPS: Invalid E-Hash1 length %u", 331 len); 332 return -1; 333 } 334 attr->e_hash1 = pos; 335 break; 336 case ATTR_E_HASH2: 337 if (len != WPS_HASH_LEN) { 338 wpa_printf(MSG_DEBUG, "WPS: Invalid E-Hash2 length %u", 339 len); 340 return -1; 341 } 342 attr->e_hash2 = pos; 343 break; 344 case ATTR_R_SNONCE1: 345 if (len != WPS_SECRET_NONCE_LEN) { 346 wpa_printf(MSG_DEBUG, "WPS: Invalid R-SNonce1 length " 347 "%u", len); 348 return -1; 349 } 350 attr->r_snonce1 = pos; 351 break; 352 case ATTR_R_SNONCE2: 353 if (len != WPS_SECRET_NONCE_LEN) { 354 wpa_printf(MSG_DEBUG, "WPS: Invalid R-SNonce2 length " 355 "%u", len); 356 return -1; 357 } 358 attr->r_snonce2 = pos; 359 break; 360 case ATTR_E_SNONCE1: 361 if (len != WPS_SECRET_NONCE_LEN) { 362 wpa_printf(MSG_DEBUG, "WPS: Invalid E-SNonce1 length " 363 "%u", len); 364 return -1; 365 } 366 attr->e_snonce1 = pos; 367 break; 368 case ATTR_E_SNONCE2: 369 if (len != WPS_SECRET_NONCE_LEN) { 370 wpa_printf(MSG_DEBUG, "WPS: Invalid E-SNonce2 length " 371 "%u", len); 372 return -1; 373 } 374 attr->e_snonce2 = pos; 375 break; 376 case ATTR_KEY_WRAP_AUTH: 377 if (len != WPS_KWA_LEN) { 378 wpa_printf(MSG_DEBUG, "WPS: Invalid Key Wrap " 379 "Authenticator length %u", len); 380 return -1; 381 } 382 attr->key_wrap_auth = pos; 383 break; 384 case ATTR_AUTH_TYPE: 385 if (len != 2) { 386 wpa_printf(MSG_DEBUG, "WPS: Invalid Authentication " 387 "Type length %u", len); 388 return -1; 389 } 390 attr->auth_type = pos; 391 break; 392 case ATTR_ENCR_TYPE: 393 if (len != 2) { 394 wpa_printf(MSG_DEBUG, "WPS: Invalid Encryption " 395 "Type length %u", len); 396 return -1; 397 } 398 attr->encr_type = pos; 399 break; 400 case ATTR_NETWORK_INDEX: 401 if (len != 1) { 402 wpa_printf(MSG_DEBUG, "WPS: Invalid Network Index " 403 "length %u", len); 404 return -1; 405 } 406 attr->network_idx = pos; 407 break; 408 case ATTR_NETWORK_KEY_INDEX: 409 if (len != 1) { 410 wpa_printf(MSG_DEBUG, "WPS: Invalid Network Key Index " 411 "length %u", len); 412 return -1; 413 } 414 attr->network_key_idx = pos; 415 break; 416 case ATTR_MAC_ADDR: 417 if (len != ETH_ALEN) { 418 wpa_printf(MSG_DEBUG, "WPS: Invalid MAC Address " 419 "length %u", len); 420 return -1; 421 } 422 attr->mac_addr = pos; 423 break; 424 case ATTR_SELECTED_REGISTRAR: 425 if (len != 1) { 426 wpa_printf(MSG_DEBUG, "WPS: Invalid Selected Registrar" 427 " length %u", len); 428 return -1; 429 } 430 attr->selected_registrar = pos; 431 break; 432 case ATTR_REQUEST_TYPE: 433 if (len != 1) { 434 wpa_printf(MSG_DEBUG, "WPS: Invalid Request Type " 435 "length %u", len); 436 return -1; 437 } 438 attr->request_type = pos; 439 break; 440 case ATTR_RESPONSE_TYPE: 441 if (len != 1) { 442 wpa_printf(MSG_DEBUG, "WPS: Invalid Response Type " 443 "length %u", len); 444 return -1; 445 } 446 attr->response_type = pos; 447 break; 448 case ATTR_MANUFACTURER: 449 attr->manufacturer = pos; 450 if (len > WPS_MANUFACTURER_MAX_LEN) 451 attr->manufacturer_len = WPS_MANUFACTURER_MAX_LEN; 452 else 453 attr->manufacturer_len = len; 454 break; 455 case ATTR_MODEL_NAME: 456 attr->model_name = pos; 457 if (len > WPS_MODEL_NAME_MAX_LEN) 458 attr->model_name_len = WPS_MODEL_NAME_MAX_LEN; 459 else 460 attr->model_name_len = len; 461 break; 462 case ATTR_MODEL_NUMBER: 463 attr->model_number = pos; 464 if (len > WPS_MODEL_NUMBER_MAX_LEN) 465 attr->model_number_len = WPS_MODEL_NUMBER_MAX_LEN; 466 else 467 attr->model_number_len = len; 468 break; 469 case ATTR_SERIAL_NUMBER: 470 attr->serial_number = pos; 471 if (len > WPS_SERIAL_NUMBER_MAX_LEN) 472 attr->serial_number_len = WPS_SERIAL_NUMBER_MAX_LEN; 473 else 474 attr->serial_number_len = len; 475 break; 476 case ATTR_DEV_NAME: 477 if (len > WPS_DEV_NAME_MAX_LEN) { 478 wpa_printf(MSG_DEBUG, 479 "WPS: Ignore too long Device Name (len=%u)", 480 len); 481 break; 482 } 483 attr->dev_name = pos; 484 attr->dev_name_len = len; 485 break; 486 case ATTR_PUBLIC_KEY: 487 /* 488 * The Public Key attribute is supposed to be exactly 192 bytes 489 * in length. Allow couple of bytes shorter one to try to 490 * interoperate with implementations that do not use proper 491 * zero-padding. 492 */ 493 if (len < 190 || len > 192) { 494 wpa_printf(MSG_DEBUG, 495 "WPS: Ignore Public Key with unexpected length %u", 496 len); 497 break; 498 } 499 attr->public_key = pos; 500 attr->public_key_len = len; 501 break; 502 case ATTR_ENCR_SETTINGS: 503 attr->encr_settings = pos; 504 attr->encr_settings_len = len; 505 break; 506 case ATTR_CRED: 507 if (attr->num_cred >= MAX_CRED_COUNT) { 508 wpa_printf(MSG_DEBUG, "WPS: Skipped Credential " 509 "attribute (max %d credentials)", 510 MAX_CRED_COUNT); 511 break; 512 } 513 attr->cred[attr->num_cred] = pos; 514 attr->cred_len[attr->num_cred] = len; 515 attr->num_cred++; 516 break; 517 case ATTR_SSID: 518 if (len > SSID_MAX_LEN) { 519 wpa_printf(MSG_DEBUG, 520 "WPS: Ignore too long SSID (len=%u)", len); 521 break; 522 } 523 attr->ssid = pos; 524 attr->ssid_len = len; 525 break; 526 case ATTR_NETWORK_KEY: 527 attr->network_key = pos; 528 attr->network_key_len = len; 529 break; 530 case ATTR_AP_SETUP_LOCKED: 531 if (len != 1) { 532 wpa_printf(MSG_DEBUG, "WPS: Invalid AP Setup Locked " 533 "length %u", len); 534 return -1; 535 } 536 attr->ap_setup_locked = pos; 537 break; 538 case ATTR_REQUESTED_DEV_TYPE: 539 if (len != WPS_DEV_TYPE_LEN) { 540 wpa_printf(MSG_DEBUG, "WPS: Invalid Requested Device " 541 "Type length %u", len); 542 return -1; 543 } 544 if (attr->num_req_dev_type >= MAX_REQ_DEV_TYPE_COUNT) { 545 wpa_printf(MSG_DEBUG, "WPS: Skipped Requested Device " 546 "Type attribute (max %u types)", 547 MAX_REQ_DEV_TYPE_COUNT); 548 break; 549 } 550 attr->req_dev_type[attr->num_req_dev_type] = pos; 551 attr->num_req_dev_type++; 552 break; 553 case ATTR_SECONDARY_DEV_TYPE_LIST: 554 if (len > WPS_SEC_DEV_TYPE_MAX_LEN || 555 (len % WPS_DEV_TYPE_LEN) > 0) { 556 wpa_printf(MSG_DEBUG, "WPS: Invalid Secondary Device " 557 "Type length %u", len); 558 return -1; 559 } 560 attr->sec_dev_type_list = pos; 561 attr->sec_dev_type_list_len = len; 562 break; 563 case ATTR_VENDOR_EXT: 564 if (wps_parse_vendor_ext(attr, pos, len) < 0) 565 return -1; 566 break; 567 case ATTR_AP_CHANNEL: 568 if (len != 2) { 569 wpa_printf(MSG_DEBUG, "WPS: Invalid AP Channel " 570 "length %u", len); 571 return -1; 572 } 573 attr->ap_channel = pos; 574 break; 575 default: 576 wpa_printf(MSG_DEBUG, "WPS: Unsupported attribute type 0x%x " 577 "len=%u", type, len); 578 break; 579 } 580 581 return 0; 582 } 583 584 585 int wps_parse_msg(const struct wpabuf *msg, struct wps_parse_attr *attr) 586 { 587 const u8 *pos, *end; 588 u16 type, len; 589 #ifdef WPS_WORKAROUNDS 590 u16 prev_type = 0; 591 #endif /* WPS_WORKAROUNDS */ 592 593 os_memset(attr, 0, sizeof(*attr)); 594 pos = wpabuf_head(msg); 595 end = pos + wpabuf_len(msg); 596 597 while (pos < end) { 598 if (end - pos < 4) { 599 wpa_printf(MSG_DEBUG, "WPS: Invalid message - " 600 "%lu bytes remaining", 601 (unsigned long) (end - pos)); 602 return -1; 603 } 604 605 type = WPA_GET_BE16(pos); 606 pos += 2; 607 len = WPA_GET_BE16(pos); 608 pos += 2; 609 wpa_printf(MSG_EXCESSIVE, "WPS: attr type=0x%x len=%u", 610 type, len); 611 if (len > end - pos) { 612 wpa_printf(MSG_DEBUG, "WPS: Attribute overflow"); 613 wpa_hexdump_buf(MSG_MSGDUMP, "WPS: Message data", msg); 614 #ifdef WPS_WORKAROUNDS 615 /* 616 * Some deployed APs seem to have a bug in encoding of 617 * Network Key attribute in the Credential attribute 618 * where they add an extra octet after the Network Key 619 * attribute at least when open network is being 620 * provisioned. 621 */ 622 if ((type & 0xff00) != 0x1000 && 623 prev_type == ATTR_NETWORK_KEY) { 624 wpa_printf(MSG_DEBUG, "WPS: Workaround - try " 625 "to skip unexpected octet after " 626 "Network Key"); 627 pos -= 3; 628 continue; 629 } 630 #endif /* WPS_WORKAROUNDS */ 631 return -1; 632 } 633 634 #ifdef WPS_WORKAROUNDS 635 if (type == 0 && len == 0) { 636 /* 637 * Mac OS X 10.6 seems to be adding 0x00 padding to the 638 * end of M1. Skip those to avoid interop issues. 639 */ 640 int i; 641 for (i = 0; i < end - pos; i++) { 642 if (pos[i]) 643 break; 644 } 645 if (i == end - pos) { 646 wpa_printf(MSG_DEBUG, "WPS: Workaround - skip " 647 "unexpected message padding"); 648 break; 649 } 650 } 651 #endif /* WPS_WORKAROUNDS */ 652 653 if (wps_set_attr(attr, type, pos, len) < 0) 654 return -1; 655 656 #ifdef WPS_WORKAROUNDS 657 prev_type = type; 658 #endif /* WPS_WORKAROUNDS */ 659 pos += len; 660 } 661 662 return 0; 663 } 664
