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         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 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         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                 if (cfg.pin) {
 211                         wps_registrar_add_pin(data->wps_ctx->registrar, uuid_e,
 212                                               cfg.pin, cfg.pin_len);
 213                 }
 214         }
 215
 216         return data;
 217 }
 218
 219
 220 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
 221 {
 222         struct eap_wsc_data *data = priv;
 223         wpabuf_free(data->in_buf);
 224         wpabuf_free(data->out_buf);
 225         wps_deinit(data->wps);
 226         wps_registrar_deinit(data->wps_ctx->registrar);
 227         data->wps_ctx->registrar = NULL;
 228         os_free(data->wps_ctx->network_key);
 229         data->wps_ctx->network_key = NULL;
 230         os_free(data);
 231 }
 232
 233
 234 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
 235                                          struct eap_method_ret *ret, u8 id)
 236 {
 237         struct wpabuf *resp;
 238         u8 flags;
 239         size_t send_len, plen;
 240
 241         ret->ignore = FALSE;
 242         wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
 243         ret->allowNotifications = TRUE;
 244
 245         flags = 0;
 246         send_len = wpabuf_len(data->out_buf) - data->out_used;
 247         if (2 + send_len > data->fragment_size) {
 248                 send_len = data->fragment_size - 2;
 249                 flags |= WSC_FLAGS_MF;
 250                 if (data->out_used == 0) {
 251                         flags |= WSC_FLAGS_LF;
 252                         send_len -= 2;
 253                 }
 254         }
 255         plen = 2 + send_len;
 256         if (flags & WSC_FLAGS_LF)
 257                 plen += 2;
 258         resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 259                              EAP_CODE_RESPONSE, id);
 260         if (resp == NULL)
 261                 return NULL;
 262
 263         wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
 264         wpabuf_put_u8(resp, flags); /* Flags */
 265         if (flags & WSC_FLAGS_LF)
 266                 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
 267
 268         wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
 269                         send_len);
 270         data->out_used += send_len;
 271
 272         ret->methodState = METHOD_MAY_CONT;
 273         ret->decision = DECISION_FAIL;
 274
 275         if (data->out_used == wpabuf_len(data->out_buf)) {
 276                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 277                            "(message sent completely)",
 278                            (unsigned long) send_len);
 279                 wpabuf_free(data->out_buf);
 280                 data->out_buf = NULL;
 281                 data->out_used = 0;
 282                 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
 283                     data->out_op_code == WSC_NACK ||
 284                     data->out_op_code == WSC_Done) {
 285                         eap_wsc_state(data, FAIL);
 286                         ret->methodState = METHOD_DONE;
 287                 } else
 288                         eap_wsc_state(data, MESG);
 289         } else {
 290                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 291                            "(%lu more to send)", (unsigned long) send_len,
 292                            (unsigned long) wpabuf_len(data->out_buf) -
 293                            data->out_used);
 294                 eap_wsc_state(data, WAIT_FRAG_ACK);
 295         }
 296
 297         return resp;
 298 }
 299
 300
 301 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 302                                 const u8 *buf, size_t len, u8 op_code)
 303 {
 304         /* Process continuation of a pending message */
 305         if (op_code != data->in_op_code) {
 306                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 307                            "fragment (expected %d)",
 308                            op_code, data->in_op_code);
 309                 return -1;
 310         }
 311
 312         if (len > wpabuf_tailroom(data->in_buf)) {
 313                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 314                 eap_wsc_state(data, FAIL);
 315                 return -1;
 316         }
 317
 318         wpabuf_put_data(data->in_buf, buf, len);
 319         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
 320                    "for %lu bytes more", (unsigned long) len,
 321                    (unsigned long) wpabuf_tailroom(data->in_buf));
 322
 323         return 0;
 324 }
 325
 326
 327 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
 328                                                 struct eap_method_ret *ret,
 329                                                 u8 id, u8 flags, u8 op_code,
 330                                                 u16 message_length,
 331                                                 const u8 *buf, size_t len)
 332 {
 333         /* Process a fragment that is not the last one of the message */
 334         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 335                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
 336                            "fragmented packet");
 337                 ret->ignore = TRUE;
 338                 return NULL;
 339         }
 340
 341         if (data->in_buf == NULL) {
 342                 /* First fragment of the message */
 343                 data->in_buf = wpabuf_alloc(message_length);
 344                 if (data->in_buf == NULL) {
 345                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 346                                    "message");
 347                         ret->ignore = TRUE;
 348                         return NULL;
 349                 }
 350                 data->in_op_code = op_code;
 351                 wpabuf_put_data(data->in_buf, buf, len);
 352                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
 353                            "fragment, waiting for %lu bytes more",
 354                            (unsigned long) len,
 355                            (unsigned long) wpabuf_tailroom(data->in_buf));
 356         }
 357
 358         return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
 359 }
 360
 361
 362 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
 363                                        struct eap_method_ret *ret,
 364                                        const struct wpabuf *reqData)
 365 {
 366         struct eap_wsc_data *data = priv;
 367         const u8 *start, *pos, *end;
 368         size_t len;
 369         u8 op_code, flags, id;
 370         u16 message_length = 0;
 371         enum wps_process_res res;
 372         struct wpabuf tmpbuf;
 373
 374         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
 375                                &len);
 376         if (pos == NULL || len < 2) {
 377                 ret->ignore = TRUE;
 378                 return NULL;
 379         }
 380
 381         id = eap_get_id(reqData);
 382
 383         start = pos;
 384         end = start + len;
 385
 386         op_code = *pos++;
 387         flags = *pos++;
 388         if (flags & WSC_FLAGS_LF) {
 389                 if (end - pos < 2) {
 390                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 391                         ret->ignore = TRUE;
 392                         return NULL;
 393                 }
 394                 message_length = WPA_GET_BE16(pos);
 395                 pos += 2;
 396
 397                 if (message_length < end - pos) {
 398                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 399                                    "Length");
 400                         ret->ignore = TRUE;
 401                         return NULL;
 402                 }
 403         }
 404
 405         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 406                    "Flags 0x%x Message Length %d",
 407                    op_code, flags, message_length);
 408
 409         if (data->state == WAIT_FRAG_ACK) {
 410                 if (op_code != WSC_FRAG_ACK) {
 411                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 412                                    "in WAIT_FRAG_ACK state", op_code);
 413                         ret->ignore = TRUE;
 414                         return NULL;
 415                 }
 416                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 417                 eap_wsc_state(data, MESG);
 418                 return eap_wsc_build_msg(data, ret, id);
 419         }
 420
 421         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 422             op_code != WSC_Done && op_code != WSC_Start) {
 423                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 424                            op_code);
 425                 ret->ignore = TRUE;
 426                 return NULL;
 427         }
 428
 429         if (data->state == WAIT_START) {
 430                 if (op_code != WSC_Start) {
 431                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 432                                    "in WAIT_START state", op_code);
 433                         ret->ignore = TRUE;
 434                         return NULL;
 435                 }
 436                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
 437                 eap_wsc_state(data, MESG);
 438                 /* Start message has empty payload, skip processing */
 439                 goto send_msg;
 440         } else if (op_code == WSC_Start) {
 441                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 442                            op_code);
 443                 ret->ignore = TRUE;
 444                 return NULL;
 445         }
 446
 447         if (data->in_buf &&
 448             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 449                 ret->ignore = TRUE;
 450                 return NULL;
 451         }
 452
 453         if (flags & WSC_FLAGS_MF) {
 454                 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
 455                                                 message_length, pos,
 456                                                 end - pos);
 457         }
 458
 459         if (data->in_buf == NULL) {
 460                 /* Wrap unfragmented messages as wpabuf without extra copy */
 461                 wpabuf_set(&tmpbuf, pos, end - pos);
 462                 data->in_buf = &tmpbuf;
 463         }
 464
 465         res = wps_process_msg(data->wps, op_code, data->in_buf);
 466         switch (res) {
 467         case WPS_DONE:
 468                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 469                            "successfully - wait for EAP failure");
 470                 eap_wsc_state(data, FAIL);
 471                 break;
 472         case WPS_CONTINUE:
 473                 eap_wsc_state(data, MESG);
 474                 break;
 475         case WPS_FAILURE:
 476                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 477                 eap_wsc_state(data, FAIL);
 478                 break;
 479         case WPS_PENDING:
 480                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing pending");
 481                 ret->ignore = TRUE;
 482                 if (data->in_buf == &tmpbuf)
 483                         data->in_buf = NULL;
 484                 return NULL;
 485         }
 486
 487         if (data->in_buf != &tmpbuf)
 488                 wpabuf_free(data->in_buf);
 489         data->in_buf = NULL;
 490
 491 send_msg:
 492         if (data->out_buf == NULL) {
 493                 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
 494                 if (data->out_buf == NULL) {
 495                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
 496                                    "message from WPS");
 497                         return NULL;
 498                 }
 499                 data->out_used = 0;
 500         }
 501
 502         eap_wsc_state(data, MESG);
 503         return eap_wsc_build_msg(data, ret, id);
 504 }
 505
 506
 507 int eap_peer_wsc_register(void)
 508 {
 509         struct eap_method *eap;
 510         int ret;
 511
 512         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 513                                     EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 514                                     "WSC");
 515         if (eap == NULL)
 516                 return -1;
 517
 518         eap->init = eap_wsc_init;
 519         eap->deinit = eap_wsc_deinit;
 520         eap->process = eap_wsc_process;
 521
 522         ret = eap_peer_method_register(eap);
 523         if (ret)
 524                 eap_peer_method_free(eap);
 525         return ret;
 526 }