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, MESG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
  27         int registrar;
  28         struct wpabuf *in_buf;
  29         struct wpabuf *out_buf;
  30         enum wsc_op_code 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 MESG:
  44                 return "MESG";
  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 ? MESG : 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
 166         phase1 = eap_get_config_phase1(sm);
 167         if (phase1 == NULL) {
 168                 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
 169                            "set");
 170                 os_free(data);
 171                 return NULL;
 172         }
 173
 174         pos = os_strstr(phase1, "pin=");
 175         if (pos) {
 176                 pos += 4;
 177                 cfg.pin = (const u8 *) pos;
 178                 while (*pos != '\0' && *pos != ' ')
 179                         pos++;
 180                 cfg.pin_len = pos - (const char *) cfg.pin;
 181         } else {
 182                 pos = os_strstr(phase1, "pbc=1");
 183                 if (pos)
 184                         cfg.pbc = 1;
 185         }
 186
 187         if (cfg.pin == NULL && !cfg.pbc) {
 188                 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
 189                            "configuration data");
 190                 os_free(data);
 191                 return NULL;
 192         }
 193
 194         data->wps = wps_init(&cfg);
 195         if (data->wps == NULL) {
 196                 os_free(data);
 197                 return NULL;
 198         }
 199         data->fragment_size = WSC_FRAGMENT_SIZE;
 200
 201         if (registrar && cfg.pin) {
 202                 wps_registrar_add_pin(data->wps_ctx->registrar, NULL,
 203                                       cfg.pin, cfg.pin_len);
 204         }
 205
 206         return data;
 207 }
 208
 209
 210 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
 211 {
 212         struct eap_wsc_data *data = priv;
 213         wpabuf_free(data->in_buf);
 214         wpabuf_free(data->out_buf);
 215         wps_deinit(data->wps);
 216         wps_registrar_deinit(data->wps_ctx->registrar);
 217         data->wps_ctx->registrar = NULL;
 218         os_free(data->wps_ctx->network_key);
 219         data->wps_ctx->network_key = NULL;
 220         os_free(data);
 221 }
 222
 223
 224 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
 225                                          struct eap_method_ret *ret, u8 id)
 226 {
 227         struct wpabuf *resp;
 228         u8 flags;
 229         size_t send_len, plen;
 230
 231         ret->ignore = FALSE;
 232         wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
 233         ret->allowNotifications = TRUE;
 234
 235         flags = 0;
 236         send_len = wpabuf_len(data->out_buf) - data->out_used;
 237         if (2 + send_len > data->fragment_size) {
 238                 send_len = data->fragment_size - 2;
 239                 flags |= WSC_FLAGS_MF;
 240                 if (data->out_used == 0) {
 241                         flags |= WSC_FLAGS_LF;
 242                         send_len -= 2;
 243                 }
 244         }
 245         plen = 2 + send_len;
 246         if (flags & WSC_FLAGS_LF)
 247                 plen += 2;
 248         resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 249                              EAP_CODE_RESPONSE, id);
 250         if (resp == NULL)
 251                 return NULL;
 252
 253         wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
 254         wpabuf_put_u8(resp, flags); /* Flags */
 255         if (flags & WSC_FLAGS_LF)
 256                 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
 257
 258         wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
 259                         send_len);
 260         data->out_used += send_len;
 261
 262         ret->methodState = METHOD_MAY_CONT;
 263         ret->decision = DECISION_FAIL;
 264
 265         if (data->out_used == wpabuf_len(data->out_buf)) {
 266                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 267                            "(message sent completely)",
 268                            (unsigned long) send_len);
 269                 wpabuf_free(data->out_buf);
 270                 data->out_buf = NULL;
 271                 data->out_used = 0;
 272                 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
 273                     data->out_op_code == WSC_NACK ||
 274                     data->out_op_code == WSC_Done) {
 275                         eap_wsc_state(data, FAIL);
 276                         ret->methodState = METHOD_DONE;
 277                 } else
 278                         eap_wsc_state(data, MESG);
 279         } else {
 280                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 281                            "(%lu more to send)", (unsigned long) send_len,
 282                            (unsigned long) wpabuf_len(data->out_buf) -
 283                            data->out_used);
 284                 eap_wsc_state(data, WAIT_FRAG_ACK);
 285         }
 286
 287         return resp;
 288 }
 289
 290
 291 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 292                                 const u8 *buf, size_t len, u8 op_code)
 293 {
 294         /* Process continuation of a pending message */
 295         if (op_code != data->in_op_code) {
 296                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 297                            "fragment (expected %d)",
 298                            op_code, data->in_op_code);
 299                 return -1;
 300         }
 301
 302         if (len > wpabuf_tailroom(data->in_buf)) {
 303                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 304                 eap_wsc_state(data, FAIL);
 305                 return -1;
 306         }
 307
 308         wpabuf_put_data(data->in_buf, buf, len);
 309         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
 310                    "for %lu bytes more", (unsigned long) len,
 311                    (unsigned long) wpabuf_tailroom(data->in_buf));
 312
 313         return 0;
 314 }
 315
 316
 317 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
 318                                                 struct eap_method_ret *ret,
 319                                                 u8 id, u8 flags, u8 op_code,
 320                                                 u16 message_length,
 321                                                 const u8 *buf, size_t len)
 322 {
 323         /* Process a fragment that is not the last one of the message */
 324         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 325                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
 326                            "fragmented packet");
 327                 ret->ignore = TRUE;
 328                 return NULL;
 329         }
 330
 331         if (data->in_buf == NULL) {
 332                 /* First fragment of the message */
 333                 data->in_buf = wpabuf_alloc(message_length);
 334                 if (data->in_buf == NULL) {
 335                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 336                                    "message");
 337                         ret->ignore = TRUE;
 338                         return NULL;
 339                 }
 340                 data->in_op_code = op_code;
 341                 wpabuf_put_data(data->in_buf, buf, len);
 342                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
 343                            "fragment, waiting for %lu bytes more",
 344                            (unsigned long) len,
 345                            (unsigned long) wpabuf_tailroom(data->in_buf));
 346         }
 347
 348         return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
 349 }
 350
 351
 352 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
 353                                        struct eap_method_ret *ret,
 354                                        const struct wpabuf *reqData)
 355 {
 356         struct eap_wsc_data *data = priv;
 357         const u8 *start, *pos, *end;
 358         size_t len;
 359         u8 op_code, flags, id;
 360         u16 message_length = 0;
 361         enum wps_process_res res;
 362         struct wpabuf tmpbuf;
 363
 364         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
 365                                &len);
 366         if (pos == NULL || len < 2) {
 367                 ret->ignore = TRUE;
 368                 return NULL;
 369         }
 370
 371         id = eap_get_id(reqData);
 372
 373         start = pos;
 374         end = start + len;
 375
 376         op_code = *pos++;
 377         flags = *pos++;
 378         if (flags & WSC_FLAGS_LF) {
 379                 if (end - pos < 2) {
 380                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 381                         ret->ignore = TRUE;
 382                         return NULL;
 383                 }
 384                 message_length = WPA_GET_BE16(pos);
 385                 pos += 2;
 386
 387                 if (message_length < end - pos) {
 388                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 389                                    "Length");
 390                         ret->ignore = TRUE;
 391                         return NULL;
 392                 }
 393         }
 394
 395         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 396                    "Flags 0x%x Message Length %d",
 397                    op_code, flags, message_length);
 398
 399         if (data->state == WAIT_FRAG_ACK) {
 400                 if (op_code != WSC_FRAG_ACK) {
 401                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 402                                    "in WAIT_FRAG_ACK state", op_code);
 403                         ret->ignore = TRUE;
 404                         return NULL;
 405                 }
 406                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 407                 eap_wsc_state(data, MESG);
 408                 return eap_wsc_build_msg(data, ret, id);
 409         }
 410
 411         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 412             op_code != WSC_Done && op_code != WSC_Start) {
 413                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 414                            op_code);
 415                 ret->ignore = TRUE;
 416                 return NULL;
 417         }
 418
 419         if (data->state == WAIT_START) {
 420                 if (op_code != WSC_Start) {
 421                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 422                                    "in WAIT_START state", op_code);
 423                         ret->ignore = TRUE;
 424                         return NULL;
 425                 }
 426                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
 427                 eap_wsc_state(data, MESG);
 428                 /* Start message has empty payload, skip processing */
 429                 goto send_msg;
 430         } else if (op_code == WSC_Start) {
 431                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 432                            op_code);
 433                 ret->ignore = TRUE;
 434                 return NULL;
 435         }
 436
 437         if (data->in_buf &&
 438             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 439                 ret->ignore = TRUE;
 440                 return NULL;
 441         }
 442
 443         if (flags & WSC_FLAGS_MF) {
 444                 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
 445                                                 message_length, pos,
 446                                                 end - pos);
 447         }
 448
 449         if (data->in_buf == NULL) {
 450                 /* Wrap unfragmented messages as wpabuf without extra copy */
 451                 wpabuf_set(&tmpbuf, pos, end - pos);
 452                 data->in_buf = &tmpbuf;
 453         }
 454
 455         res = wps_process_msg(data->wps, op_code, data->in_buf);
 456         switch (res) {
 457         case WPS_DONE:
 458                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 459                            "successfully - wait for EAP failure");
 460                 eap_wsc_state(data, FAIL);
 461                 break;
 462         case WPS_CONTINUE:
 463                 eap_wsc_state(data, MESG);
 464                 break;
 465         case WPS_FAILURE:
 466                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 467                 eap_wsc_state(data, FAIL);
 468                 break;
 469         case WPS_PENDING:
 470                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing pending");
 471                 ret->ignore = TRUE;
 472                 if (data->in_buf == &tmpbuf)
 473                         data->in_buf = NULL;
 474                 return NULL;
 475         }
 476
 477         if (data->in_buf != &tmpbuf)
 478                 wpabuf_free(data->in_buf);
 479         data->in_buf = NULL;
 480
 481 send_msg:
 482         if (data->out_buf == NULL) {
 483                 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
 484                 if (data->out_buf == NULL) {
 485                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
 486                                    "message from WPS");
 487                         return NULL;
 488                 }
 489                 data->out_used = 0;
 490         }
 491
 492         eap_wsc_state(data, MESG);
 493         return eap_wsc_build_msg(data, ret, id);
 494 }
 495
 496
 497 int eap_peer_wsc_register(void)
 498 {
 499         struct eap_method *eap;
 500         int ret;
 501
 502         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 503                                     EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 504                                     "WSC");
 505         if (eap == NULL)
 506                 return -1;
 507
 508         eap->init = eap_wsc_init;
 509         eap->deinit = eap_wsc_deinit;
 510         eap->process = eap_wsc_process;
 511
 512         ret = eap_peer_method_register(eap);
 513         if (ret)
 514                 eap_peer_method_free(eap);
 515         return ret;
 516 }