src/eap_peer/eap_wsc.c

   1 /*
   2  * EAP-WSC peer for Wi-Fi Protected Setup
   3  * Copyright (c) 2007-2008, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "uuid.h"
  19 #include "eap_i.h"
  20 #include "eap_common/eap_wsc_common.h"
  21 #include "wps/wps.h"
  22 #include "wps/wps_defs.h"
  23
  24
  25 struct eap_wsc_data {
  26         enum { WAIT_START, MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
  27         int registrar;
  28         struct wpabuf *in_buf;
  29         struct wpabuf *out_buf;
  30         u8 in_op_code, out_op_code;
  31         size_t out_used;
  32         size_t fragment_size;
  33         struct wps_data *wps;
  34         struct wps_context *wps_ctx;
  35 };
  36
  37
  38 static const char * eap_wsc_state_txt(int state)
  39 {
  40         switch (state) {
  41         case WAIT_START:
  42                 return "WAIT_START";
  43         case MSG:
  44                 return "MSG";
  45         case FRAG_ACK:
  46                 return "FRAG_ACK";
  47         case WAIT_FRAG_ACK:
  48                 return "WAIT_FRAG_ACK";
  49         case DONE:
  50                 return "DONE";
  51         case FAIL:
  52                 return "FAIL";
  53         default:
  54                 return "?";
  55         }
  56 }
  57
  58
  59 static void eap_wsc_state(struct eap_wsc_data *data, int state)
  60 {
  61         wpa_printf(MSG_DEBUG, "EAP-WSC: %s -> %s",
  62                    eap_wsc_state_txt(data->state),
  63                    eap_wsc_state_txt(state));
  64         data->state = state;
  65 }
  66
  67
  68 static int eap_wsc_new_psk_cb(void *ctx, const u8 *mac_addr, const u8 *psk,
  69                               size_t psk_len)
  70 {
  71         /* struct eap_wsc_data *data = ctx; */
  72
  73         wpa_printf(MSG_DEBUG, "EAP-SC: Received new WPA/WPA2-PSK from WPS for "
  74                    "STA " MACSTR, MAC2STR(mac_addr));
  75         wpa_hexdump_key(MSG_DEBUG, "Per-device PSK", psk, psk_len);
  76
  77         /* TODO */
  78
  79         return 0;
  80 }
  81
  82
  83 static void eap_wsc_pin_needed_cb(void *ctx, const u8 *uuid_e,
  84                                   const struct wps_device_data *dev)
  85 {
  86         /* struct eap_wsc_data *data = ctx; */
  87         char uuid[40], txt[400];
  88         int len;
  89         if (uuid_bin2str(uuid_e, uuid, sizeof(uuid)))
  90                 return;
  91         wpa_printf(MSG_DEBUG, "EAP-WSC: PIN needed for E-UUID %s", uuid);
  92         len = os_snprintf(txt, sizeof(txt), "WPS-EVENT-PIN-NEEDED "
  93                           "%s " MACSTR " [%s|%s|%s|%s|%s|%d-%08X-%d]",
  94                           uuid, MAC2STR(dev->mac_addr), dev->device_name,
  95                           dev->manufacturer, dev->model_name,
  96                           dev->model_number, dev->serial_number,
  97                           dev->categ, dev->oui, dev->sub_categ);
  98         if (len > 0 && len < (int) sizeof(txt))
  99                 wpa_printf(MSG_INFO, "%s", txt);
 100 }
 101
 102
 103 static void * eap_wsc_init(struct eap_sm *sm)
 104 {
 105         struct eap_wsc_data *data;
 106         const u8 *identity;
 107         size_t identity_len;
 108         int registrar;
 109         struct wps_config cfg;
 110         u8 uuid[UUID_LEN];
 111         const char *pos;
 112         const char *phase1;
 113         struct wps_context *wps = NULL;
 114
 115         identity = eap_get_config_identity(sm, &identity_len);
 116
 117         if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
 118             os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
 119                 registrar = 1; /* Supplicant is Registrar */
 120         else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
 121             os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
 122                 registrar = 0; /* Supplicant is Enrollee */
 123         else {
 124                 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
 125                                   identity, identity_len);
 126                 return NULL;
 127         }
 128
 129         data = os_zalloc(sizeof(*data));
 130         if (data == NULL)
 131                 return NULL;
 132         data->state = registrar ? MSG : WAIT_START;
 133         data->registrar = registrar;
 134
 135         if (registrar) {
 136                 struct wps_registrar_config rcfg;
 137
 138                 wps = os_zalloc(sizeof(*wps));
 139                 if (wps == NULL) {
 140                         os_free(data);
 141                         return NULL;
 142                 }
 143
 144                 wps->cb_ctx = data;
 145
 146                 /* TODO: configure.. */
 147                 wps->auth_types = WPS_AUTH_WPA2PSK;
 148                 wps->encr_types = WPS_ENCR_AES;
 149                 os_memcpy(wps->ssid, "test", 4);
 150                 wps->ssid_len = 4;
 151
 152                 os_memset(&rcfg, 0, sizeof(rcfg));
 153                 rcfg.new_psk_cb = eap_wsc_new_psk_cb;
 154                 rcfg.pin_needed_cb = eap_wsc_pin_needed_cb;
 155                 rcfg.cb_ctx = data;
 156
 157                 wps->registrar = wps_registrar_init(wps, &rcfg);
 158                 if (wps->registrar == NULL) {
 159                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to initialize "
 160                                    "WPS Registrar");
 161                         os_free(wps->network_key);
 162                         os_free(wps);
 163                         os_free(data);
 164                         return NULL;
 165                 }
 166
 167                 data->wps_ctx = wps;
 168         }
 169
 170         os_memset(&cfg, 0, sizeof(cfg));
 171         cfg.authenticator = 0;
 172         cfg.wps = wps;
 173         cfg.registrar = data->wps_ctx ? data->wps_ctx->registrar : NULL;
 174         cfg.enrollee_mac_addr = sm->mac_addr;
 175
 176         phase1 = eap_get_config_phase1(sm);
 177         if (phase1 == NULL) {
 178                 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
 179                            "set");
 180                 os_free(data);
 181                 return NULL;
 182         }
 183
 184         pos = os_strstr(phase1, "pin=");
 185         if (pos) {
 186                 pos += 4;
 187                 cfg.pin = (const u8 *) pos;
 188                 while (*pos != '\0' && *pos != ' ')
 189                         pos++;
 190                 cfg.pin_len = pos - (const char *) cfg.pin;
 191         } else {
 192                 pos = os_strstr(phase1, "pbc=1");
 193                 if (pos)
 194                         cfg.pbc = 1;
 195         }
 196
 197         if (cfg.pin == NULL && !cfg.pbc) {
 198                 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
 199                            "configuration data");
 200                 os_free(data);
 201                 return NULL;
 202         }
 203
 204         pos = os_strstr(phase1, "uuid=");
 205         if (pos == NULL) {
 206                 wpa_printf(MSG_INFO, "EAP-WSC: UUID not set in phase1 "
 207                            "configuration data");
 208                 os_free(data);
 209                 return NULL;
 210         }
 211         if (uuid_str2bin(pos + 5, uuid)) {
 212                 wpa_printf(MSG_INFO, "EAP-WSC: Invalid UUID in phase1 "
 213                            "configuration data");
 214                 os_free(data);
 215                 return NULL;
 216         }
 217         if (registrar && wps)
 218                 os_memcpy(wps->uuid, uuid, UUID_LEN);
 219         else
 220                 cfg.uuid = uuid;
 221         cfg.wps_cred_cb = sm->eapol_cb->wps_cred;
 222         cfg.cb_ctx = sm->eapol_ctx;
 223         data->wps = wps_init(&cfg);
 224         if (data->wps == NULL) {
 225                 os_free(data);
 226                 return NULL;
 227         }
 228         data->fragment_size = WSC_FRAGMENT_SIZE;
 229
 230
 231         if (registrar) {
 232                 /* Testing */
 233                 wpa_printf(MSG_INFO, "EAP-WSC: Registrar functionality not "
 234                            "yet fully supported - using test values");
 235                 u8 uuid_e[UUID_LEN];
 236                 os_memset(uuid_e, 0, UUID_LEN);
 237                 wps_registrar_add_pin(data->wps_ctx->registrar, uuid_e,
 238                                       (const u8 *) "12345670", 8);
 239         }
 240
 241         return data;
 242 }
 243
 244
 245 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
 246 {
 247         struct eap_wsc_data *data = priv;
 248         wpabuf_free(data->in_buf);
 249         wpabuf_free(data->out_buf);
 250         wps_deinit(data->wps);
 251         if (data->wps_ctx) {
 252                 wps_registrar_deinit(data->wps_ctx->registrar);
 253                 os_free(data->wps_ctx->network_key);
 254                 os_free(data->wps_ctx);
 255         }
 256         os_free(data);
 257 }
 258
 259
 260 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
 261                                          struct eap_method_ret *ret, u8 id)
 262 {
 263         struct wpabuf *resp;
 264         u8 flags;
 265         size_t send_len, plen;
 266
 267         ret->ignore = FALSE;
 268         wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
 269         ret->allowNotifications = TRUE;
 270
 271         flags = 0;
 272         send_len = wpabuf_len(data->out_buf) - data->out_used;
 273         if (2 + send_len > data->fragment_size) {
 274                 send_len = data->fragment_size - 2;
 275                 flags |= WSC_FLAGS_MF;
 276                 if (data->out_used == 0) {
 277                         flags |= WSC_FLAGS_LF;
 278                         send_len -= 2;
 279                 }
 280         }
 281         plen = 2 + send_len;
 282         if (flags & WSC_FLAGS_LF)
 283                 plen += 2;
 284         resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 285                              EAP_CODE_RESPONSE, id);
 286         if (resp == NULL)
 287                 return NULL;
 288
 289         wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
 290         wpabuf_put_u8(resp, flags); /* Flags */
 291         if (flags & WSC_FLAGS_LF)
 292                 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
 293
 294         wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
 295                         send_len);
 296         data->out_used += send_len;
 297
 298         ret->methodState = METHOD_MAY_CONT;
 299         ret->decision = DECISION_FAIL;
 300
 301         if (data->out_used == wpabuf_len(data->out_buf)) {
 302                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 303                            "(message sent completely)",
 304                            (unsigned long) send_len);
 305                 wpabuf_free(data->out_buf);
 306                 data->out_buf = NULL;
 307                 data->out_used = 0;
 308                 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
 309                     data->out_op_code == WSC_NACK ||
 310                     data->out_op_code == WSC_Done) {
 311                         eap_wsc_state(data, FAIL);
 312                         ret->methodState = METHOD_DONE;
 313                 } else
 314                         eap_wsc_state(data, MSG);
 315         } else {
 316                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 317                            "(%lu more to send)", (unsigned long) send_len,
 318                            (unsigned long) wpabuf_len(data->out_buf) -
 319                            data->out_used);
 320                 eap_wsc_state(data, WAIT_FRAG_ACK);
 321         }
 322
 323         return resp;
 324 }
 325
 326
 327 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 328                                 const u8 *buf, size_t len, u8 op_code)
 329 {
 330         /* Process continuation of a pending message */
 331         if (op_code != data->in_op_code) {
 332                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 333                            "fragment (expected %d)",
 334                            op_code, data->in_op_code);
 335                 return -1;
 336         }
 337
 338         if (len > wpabuf_tailroom(data->in_buf)) {
 339                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 340                 eap_wsc_state(data, FAIL);
 341                 return -1;
 342         }
 343
 344         wpabuf_put_data(data->in_buf, buf, len);
 345         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
 346                    "for %lu bytes more", (unsigned long) len,
 347                    (unsigned long) wpabuf_tailroom(data->in_buf));
 348
 349         return 0;
 350 }
 351
 352
 353 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
 354                                                 struct eap_method_ret *ret,
 355                                                 u8 id, u8 flags, u8 op_code,
 356                                                 u16 message_length,
 357                                                 const u8 *buf, size_t len)
 358 {
 359         /* Process a fragment that is not the last one of the message */
 360         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 361                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
 362                            "fragmented packet");
 363                 ret->ignore = TRUE;
 364                 return NULL;
 365         }
 366
 367         if (data->in_buf == NULL) {
 368                 /* First fragment of the message */
 369                 data->in_buf = wpabuf_alloc(message_length);
 370                 if (data->in_buf == NULL) {
 371                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 372                                    "message");
 373                         ret->ignore = TRUE;
 374                         return NULL;
 375                 }
 376                 data->in_op_code = op_code;
 377                 wpabuf_put_data(data->in_buf, buf, len);
 378                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
 379                            "fragment, waiting for %lu bytes more",
 380                            (unsigned long) len,
 381                            (unsigned long) wpabuf_tailroom(data->in_buf));
 382         }
 383
 384         return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
 385 }
 386
 387
 388 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
 389                                        struct eap_method_ret *ret,
 390                                        const struct wpabuf *reqData)
 391 {
 392         struct eap_wsc_data *data = priv;
 393         const u8 *start, *pos, *end;
 394         size_t len;
 395         u8 op_code, flags, id;
 396         u16 message_length = 0;
 397         enum wps_process_res res;
 398         struct wpabuf tmpbuf;
 399
 400         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
 401                                &len);
 402         if (pos == NULL || len < 2) {
 403                 ret->ignore = TRUE;
 404                 return NULL;
 405         }
 406
 407         id = eap_get_id(reqData);
 408
 409         start = pos;
 410         end = start + len;
 411
 412         op_code = *pos++;
 413         flags = *pos++;
 414         if (flags & WSC_FLAGS_LF) {
 415                 if (end - pos < 2) {
 416                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 417                         ret->ignore = TRUE;
 418                         return NULL;
 419                 }
 420                 message_length = WPA_GET_BE16(pos);
 421                 pos += 2;
 422
 423                 if (message_length < end - pos) {
 424                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 425                                    "Length");
 426                         ret->ignore = TRUE;
 427                         return NULL;
 428                 }
 429         }
 430
 431         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 432                    "Flags 0x%x Message Length %d",
 433                    op_code, flags, message_length);
 434
 435         if (data->state == WAIT_FRAG_ACK) {
 436                 if (op_code != WSC_FRAG_ACK) {
 437                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 438                                    "in WAIT_FRAG_ACK state", op_code);
 439                         ret->ignore = TRUE;
 440                         return NULL;
 441                 }
 442                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 443                 eap_wsc_state(data, MSG);
 444                 return eap_wsc_build_msg(data, ret, id);
 445         }
 446
 447         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 448             op_code != WSC_Done && op_code != WSC_Start) {
 449                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 450                            op_code);
 451                 ret->ignore = TRUE;
 452                 return NULL;
 453         }
 454
 455         if (data->state == WAIT_START) {
 456                 if (op_code != WSC_Start) {
 457                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 458                                    "in WAIT_START state", op_code);
 459                         ret->ignore = TRUE;
 460                         return NULL;
 461                 }
 462                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
 463                 eap_wsc_state(data, MSG);
 464                 /* Start message has empty payload, skip processing */
 465                 goto send_msg;
 466         } else if (op_code == WSC_Start) {
 467                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 468                            op_code);
 469                 ret->ignore = TRUE;
 470                 return NULL;
 471         }
 472
 473         if (data->in_buf &&
 474             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 475                 ret->ignore = TRUE;
 476                 return NULL;
 477         }
 478
 479         if (flags & WSC_FLAGS_MF) {
 480                 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
 481                                                 message_length, pos,
 482                                                 end - pos);
 483         }
 484
 485         if (data->in_buf == NULL) {
 486                 /* Wrap unfragmented messages as wpabuf without extra copy */
 487                 wpabuf_set(&tmpbuf, pos, end - pos);
 488                 data->in_buf = &tmpbuf;
 489         }
 490
 491         res = wps_process_msg(data->wps, op_code, data->in_buf);
 492         switch (res) {
 493         case WPS_DONE:
 494                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 495                            "successfully - wait for EAP failure");
 496                 eap_wsc_state(data, FAIL);
 497                 break;
 498         case WPS_CONTINUE:
 499                 eap_wsc_state(data, MSG);
 500                 break;
 501         case WPS_FAILURE:
 502                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 503                 eap_wsc_state(data, FAIL);
 504                 break;
 505         case WPS_PENDING:
 506                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing pending");
 507                 ret->ignore = TRUE;
 508                 if (data->in_buf == &tmpbuf)
 509                         data->in_buf = NULL;
 510                 return NULL;
 511         }
 512
 513         if (data->in_buf != &tmpbuf)
 514                 wpabuf_free(data->in_buf);
 515         data->in_buf = NULL;
 516
 517 send_msg:
 518         if (data->out_buf == NULL) {
 519                 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
 520                 if (data->out_buf == NULL) {
 521                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
 522                                    "message from WPS");
 523                         return NULL;
 524                 }
 525                 data->out_used = 0;
 526         }
 527
 528         eap_wsc_state(data, MSG);
 529         return eap_wsc_build_msg(data, ret, id);
 530 }
 531
 532
 533 int eap_peer_wsc_register(void)
 534 {
 535         struct eap_method *eap;
 536         int ret;
 537
 538         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 539                                     EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 540                                     "WSC");
 541         if (eap == NULL)
 542                 return -1;
 543
 544         eap->init = eap_wsc_init;
 545         eap->deinit = eap_wsc_deinit;
 546         eap->process = eap_wsc_process;
 547
 548         ret = eap_peer_method_register(eap);
 549         if (ret)
 550                 eap_peer_method_free(eap);
 551         return ret;
 552 }