vcs.maemo.org Git - wpasupplicant/blob - src/eap_server/eap_wsc.c

   1 /*
   2  * EAP-WSC server for Wi-Fi Protected Setup
   3  * Copyright (c) 2007, 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 "eap_i.h"
  19 #include "eap_common/eap_wsc_common.h"
  20 #include "wps/wps.h"
  21
  22
  23 struct eap_wsc_data {
  24         enum { START, MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
  25         int registrar;
  26         struct wpabuf *in_buf;
  27         struct wpabuf *out_buf;
  28         u8 in_op_code, out_op_code;
  29         size_t out_used;
  30         size_t fragment_size;
  31         struct wps_data *wps;
  32 };
  33
  34
  35 static const char * eap_wsc_state_txt(int state)
  36 {
  37         switch (state) {
  38         case START:
  39                 return "START";
  40         case MSG:
  41                 return "MSG";
  42         case FRAG_ACK:
  43                 return "FRAG_ACK";
  44         case WAIT_FRAG_ACK:
  45                 return "WAIT_FRAG_ACK";
  46         case DONE:
  47                 return "DONE";
  48         case FAIL:
  49                 return "FAIL";
  50         default:
  51                 return "?";
  52         }
  53 }
  54
  55
  56 static void eap_wsc_state(struct eap_wsc_data *data, int state)
  57 {
  58         wpa_printf(MSG_DEBUG, "EAP-WSC: %s -> %s",
  59                    eap_wsc_state_txt(data->state),
  60                    eap_wsc_state_txt(state));
  61         data->state = state;
  62 }
  63
  64
  65 static void * eap_wsc_init(struct eap_sm *sm)
  66 {
  67         struct eap_wsc_data *data;
  68         int registrar;
  69         struct wps_config cfg;
  70
  71         if (sm->identity && sm->identity_len == WSC_ID_REGISTRAR_LEN &&
  72             os_memcmp(sm->identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) ==
  73             0)
  74                 registrar = 0; /* Supplicant is Registrar */
  75         else if (sm->identity && sm->identity_len == WSC_ID_ENROLLEE_LEN &&
  76                  os_memcmp(sm->identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN)
  77                  == 0)
  78                 registrar = 1; /* Supplicant is Enrollee */
  79         else {
  80                 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
  81                                   sm->identity, sm->identity_len);
  82                 return NULL;
  83         }
  84
  85         data = os_zalloc(sizeof(*data));
  86         if (data == NULL)
  87                 return NULL;
  88         data->state = registrar ? START : MSG;
  89         data->registrar = registrar;
  90
  91         os_memset(&cfg, 0, sizeof(cfg));
  92         cfg.authenticator = 1;
  93         cfg.wps = sm->wps;
  94         if (registrar) {
  95                 if (sm->wps == NULL || sm->wps->registrar == NULL) {
  96                         wpa_printf(MSG_INFO, "EAP-WSC: WPS Registrar not "
  97                                    "initialized");
  98                         os_free(data);
  99                         return NULL;
 100                 }
 101                 cfg.registrar = sm->wps->registrar;
 102         } else {
 103                 if (sm->user == NULL || sm->user->password == NULL) {
 104                         wpa_printf(MSG_INFO, "EAP-WSC: No AP PIN (password) "
 105                                    "configured for Enrollee functionality");
 106                         os_free(data);
 107                         return NULL;
 108                 }
 109                 cfg.pin = sm->user->password;
 110                 cfg.pin_len = sm->user->password_len;
 111         }
 112         data->wps = wps_init(&cfg);
 113         if (data->wps == NULL) {
 114                 os_free(data);
 115                 return NULL;
 116         }
 117         data->fragment_size = WSC_FRAGMENT_SIZE;
 118
 119         return data;
 120 }
 121
 122
 123 static void eap_wsc_reset(struct eap_sm *sm, void *priv)
 124 {
 125         struct eap_wsc_data *data = priv;
 126         wpabuf_free(data->in_buf);
 127         wpabuf_free(data->out_buf);
 128         wps_deinit(data->wps);
 129         os_free(data);
 130 }
 131
 132
 133 static struct wpabuf * eap_wsc_build_start(struct eap_sm *sm,
 134                                            struct eap_wsc_data *data, u8 id)
 135 {
 136         struct wpabuf *req;
 137
 138         req = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, 2,
 139                             EAP_CODE_REQUEST, id);
 140         if (req == NULL) {
 141                 wpa_printf(MSG_ERROR, "EAP-WSC: Failed to allocate memory for "
 142                            "request");
 143                 return NULL;
 144         }
 145
 146         wpa_printf(MSG_DEBUG, "EAP-WSC: Send WSC/Start");
 147         wpabuf_put_u8(req, WSC_Start); /* Op-Code */
 148         wpabuf_put_u8(req, 0); /* Flags */
 149
 150         return req;
 151 }
 152
 153
 154 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data, u8 id)
 155 {
 156         struct wpabuf *req;
 157         u8 flags;
 158         size_t send_len, plen;
 159
 160         flags = 0;
 161         send_len = wpabuf_len(data->out_buf) - data->out_used;
 162         if (2 + send_len > data->fragment_size) {
 163                 send_len = data->fragment_size - 2;
 164                 flags |= WSC_FLAGS_MF;
 165                 if (data->out_used == 0) {
 166                         flags |= WSC_FLAGS_LF;
 167                         send_len -= 2;
 168                 }
 169         }
 170         plen = 2 + send_len;
 171         if (flags & WSC_FLAGS_LF)
 172                 plen += 2;
 173         req = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 174                             EAP_CODE_REQUEST, id);
 175         if (req == NULL) {
 176                 wpa_printf(MSG_ERROR, "EAP-WSC: Failed to allocate memory for "
 177                            "request");
 178                 return NULL;
 179         }
 180
 181         wpabuf_put_u8(req, data->out_op_code); /* Op-Code */
 182         wpabuf_put_u8(req, flags); /* Flags */
 183         if (flags & WSC_FLAGS_LF)
 184                 wpabuf_put_be16(req, wpabuf_len(data->out_buf));
 185
 186         wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
 187                         send_len);
 188         data->out_used += send_len;
 189
 190         if (data->out_used == wpabuf_len(data->out_buf)) {
 191                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 192                            "(message sent completely)",
 193                            (unsigned long) send_len);
 194                 wpabuf_free(data->out_buf);
 195                 data->out_buf = NULL;
 196                 data->out_used = 0;
 197                 eap_wsc_state(data, MSG);
 198         } else {
 199                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 200                            "(%lu more to send)", (unsigned long) send_len,
 201                            (unsigned long) wpabuf_len(data->out_buf) -
 202                            data->out_used);
 203                 eap_wsc_state(data, WAIT_FRAG_ACK);
 204         }
 205
 206         return req;
 207 }
 208
 209
 210 static struct wpabuf * eap_wsc_buildReq(struct eap_sm *sm, void *priv, u8 id)
 211 {
 212         struct eap_wsc_data *data = priv;
 213
 214         switch (data->state) {
 215         case START:
 216                 return eap_wsc_build_start(sm, data, id);
 217         case MSG:
 218                 if (data->out_buf == NULL) {
 219                         data->out_buf = wps_get_msg(data->wps,
 220                                                     &data->out_op_code);
 221                         if (data->out_buf == NULL) {
 222                                 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to "
 223                                            "receive message from WPS");
 224                                 return NULL;
 225                         }
 226                         data->out_used = 0;
 227                 }
 228                 /* pass through */
 229         case WAIT_FRAG_ACK:
 230                 return eap_wsc_build_msg(data, id);
 231         case FRAG_ACK:
 232                 return eap_wsc_build_frag_ack(id, EAP_CODE_REQUEST);
 233         default:
 234                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected state %d in "
 235                            "buildReq", data->state);
 236                 return NULL;
 237         }
 238 }
 239
 240
 241 static Boolean eap_wsc_check(struct eap_sm *sm, void *priv,
 242                              struct wpabuf *respData)
 243 {
 244         const u8 *pos;
 245         size_t len;
 246
 247         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 248                                respData, &len);
 249         if (pos == NULL || len < 2) {
 250                 wpa_printf(MSG_INFO, "EAP-WSC: Invalid frame");
 251                 return TRUE;
 252         }
 253
 254         return FALSE;
 255 }
 256
 257
 258 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 259                                 const u8 *buf, size_t len, u8 op_code)
 260 {
 261         /* Process continuation of a pending message */
 262         if (op_code != data->in_op_code) {
 263                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 264                            "fragment (expected %d)",
 265                            op_code, data->in_op_code);
 266                 eap_wsc_state(data, FAIL);
 267                 return -1;
 268         }
 269
 270         if (len > wpabuf_tailroom(data->in_buf)) {
 271                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 272                 eap_wsc_state(data, FAIL);
 273                 return -1;
 274         }
 275
 276         wpabuf_put_data(data->in_buf, buf, len);
 277         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting for %lu "
 278                    "bytes more", (unsigned long) len,
 279                    (unsigned long) wpabuf_tailroom(data->in_buf));
 280
 281         return 0;
 282 }
 283
 284
 285 static int eap_wsc_process_fragment(struct eap_wsc_data *data,
 286                                     u8 flags, u8 op_code, u16 message_length,
 287                                     const u8 *buf, size_t len)
 288 {
 289         /* Process a fragment that is not the last one of the message */
 290         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 291                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length "
 292                            "field in a fragmented packet");
 293                 return -1;
 294         }
 295
 296         if (data->in_buf == NULL) {
 297                 /* First fragment of the message */
 298                 data->in_buf = wpabuf_alloc(message_length);
 299                 if (data->in_buf == NULL) {
 300                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 301                                    "message");
 302                         return -1;
 303                 }
 304                 data->in_op_code = op_code;
 305                 wpabuf_put_data(data->in_buf, buf, len);
 306                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in "
 307                            "first fragment, waiting for %lu bytes more",
 308                            (unsigned long) len,
 309                            (unsigned long) wpabuf_tailroom(data->in_buf));
 310         }
 311
 312         return 0;
 313 }
 314
 315
 316 static void eap_wsc_process(struct eap_sm *sm, void *priv,
 317                             struct wpabuf *respData)
 318 {
 319         struct eap_wsc_data *data = priv;
 320         const u8 *start, *pos, *end;
 321         size_t len;
 322         u8 op_code, flags;
 323         u16 message_length = 0;
 324         enum wps_process_res res;
 325         struct wpabuf tmpbuf;
 326
 327         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 328                                respData, &len);
 329         if (pos == NULL || len < 2)
 330                 return; /* Should not happen; message already verified */
 331
 332         start = pos;
 333         end = start + len;
 334
 335         op_code = *pos++;
 336         flags = *pos++;
 337         if (flags & WSC_FLAGS_LF) {
 338                 if (end - pos < 2) {
 339                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 340                         return;
 341                 }
 342                 message_length = WPA_GET_BE16(pos);
 343                 pos += 2;
 344
 345                 if (message_length < end - pos) {
 346                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 347                                    "Length");
 348                         return;
 349                 }
 350         }
 351
 352         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 353                    "Flags 0x%x Message Length %d",
 354                    op_code, flags, message_length);
 355
 356         if (data->state == WAIT_FRAG_ACK) {
 357                 if (op_code != WSC_FRAG_ACK) {
 358                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 359                                    "in WAIT_FRAG_ACK state", op_code);
 360                         eap_wsc_state(data, FAIL);
 361                         return;
 362                 }
 363                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 364                 eap_wsc_state(data, MSG);
 365                 return;
 366         }
 367
 368         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 369             op_code != WSC_Done) {
 370                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 371                            op_code);
 372                 eap_wsc_state(data, FAIL);
 373                 return;
 374         }
 375
 376         if (data->in_buf &&
 377             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 378                 eap_wsc_state(data, FAIL);
 379                 return;
 380         }
 381
 382         if (flags & WSC_FLAGS_MF) {
 383                 if (eap_wsc_process_fragment(data, flags, op_code,
 384                                              message_length, pos, end - pos) <
 385                     0)
 386                         eap_wsc_state(data, FAIL);
 387                 else
 388                         eap_wsc_state(data, FRAG_ACK);
 389                 return;
 390         }
 391
 392         if (data->in_buf == NULL) {
 393                 /* Wrap unfragmented messages as wpabuf without extra copy */
 394                 wpabuf_set(&tmpbuf, pos, end - pos);
 395                 data->in_buf = &tmpbuf;
 396         }
 397
 398         res = wps_process_msg(data->wps, op_code, data->in_buf);
 399         switch (res) {
 400         case WPS_DONE:
 401                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 402                            "successfully - report EAP failure");
 403                 eap_wsc_state(data, FAIL);
 404                 break;
 405         case WPS_CONTINUE:
 406                 eap_wsc_state(data, MSG);
 407                 break;
 408         case WPS_FAILURE:
 409                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 410                 eap_wsc_state(data, FAIL);
 411                 break;
 412         case WPS_PENDING:
 413                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing pending");
 414                 sm->method_pending = METHOD_PENDING_WAIT;
 415                 break;
 416         }
 417
 418         if (data->in_buf != &tmpbuf)
 419                 wpabuf_free(data->in_buf);
 420         data->in_buf = NULL;
 421 }
 422
 423
 424 static Boolean eap_wsc_isDone(struct eap_sm *sm, void *priv)
 425 {
 426         struct eap_wsc_data *data = priv;
 427         return data->state == FAIL;
 428 }
 429
 430
 431 static Boolean eap_wsc_isSuccess(struct eap_sm *sm, void *priv)
 432 {
 433         /* EAP-WSC will always result in EAP-Failure */
 434         return FALSE;
 435 }
 436
 437
 438 int eap_server_wsc_register(void)
 439 {
 440         struct eap_method *eap;
 441         int ret;
 442
 443         eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
 444                                       EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 445                                       "WSC");
 446         if (eap == NULL)
 447                 return -1;
 448
 449         eap->init = eap_wsc_init;
 450         eap->reset = eap_wsc_reset;
 451         eap->buildReq = eap_wsc_buildReq;
 452         eap->check = eap_wsc_check;
 453         eap->process = eap_wsc_process;
 454         eap->isDone = eap_wsc_isDone;
 455         eap->isSuccess = eap_wsc_isSuccess;
 456
 457         ret = eap_server_method_register(eap);
 458         if (ret)
 459                 eap_server_method_free(eap);
 460         return ret;
 461 }