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