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.wps = wps;
 163         cfg.registrar = registrar ? data->wps_ctx->registrar : NULL;
 164
 165         phase1 = eap_get_config_phase1(sm);
 166         if (phase1 == NULL) {
 167                 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
 168                            "set");
 169                 os_free(data);
 170                 return NULL;
 171         }
 172
 173         pos = os_strstr(phase1, "pin=");
 174         if (pos) {
 175                 pos += 4;
 176                 cfg.pin = (const u8 *) pos;
 177                 while (*pos != '\0' && *pos != ' ')
 178                         pos++;
 179                 cfg.pin_len = pos - (const char *) cfg.pin;
 180         } else {
 181                 pos = os_strstr(phase1, "pbc=1");
 182                 if (pos)
 183                         cfg.pbc = 1;
 184         }
 185
 186         if (cfg.pin == NULL && !cfg.pbc) {
 187                 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
 188                            "configuration data");
 189                 os_free(data);
 190                 return NULL;
 191         }
 192
 193         data->wps = wps_init(&cfg);
 194         if (data->wps == NULL) {
 195                 os_free(data);
 196                 return NULL;
 197         }
 198         data->fragment_size = WSC_FRAGMENT_SIZE;
 199
 200         if (registrar && cfg.pin) {
 201                 wps_registrar_add_pin(data->wps_ctx->registrar, NULL,
 202                                       cfg.pin, cfg.pin_len);
 203         }
 204
 205         return data;
 206 }
 207
 208
 209 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
 210 {
 211         struct eap_wsc_data *data = priv;
 212         wpabuf_free(data->in_buf);
 213         wpabuf_free(data->out_buf);
 214         wps_deinit(data->wps);
 215         wps_registrar_deinit(data->wps_ctx->registrar);
 216         data->wps_ctx->registrar = NULL;
 217         os_free(data->wps_ctx->network_key);
 218         data->wps_ctx->network_key = NULL;
 219         os_free(data);
 220 }
 221
 222
 223 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
 224                                          struct eap_method_ret *ret, u8 id)
 225 {
 226         struct wpabuf *resp;
 227         u8 flags;
 228         size_t send_len, plen;
 229
 230         ret->ignore = FALSE;
 231         wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
 232         ret->allowNotifications = TRUE;
 233
 234         flags = 0;
 235         send_len = wpabuf_len(data->out_buf) - data->out_used;
 236         if (2 + send_len > data->fragment_size) {
 237                 send_len = data->fragment_size - 2;
 238                 flags |= WSC_FLAGS_MF;
 239                 if (data->out_used == 0) {
 240                         flags |= WSC_FLAGS_LF;
 241                         send_len -= 2;
 242                 }
 243         }
 244         plen = 2 + send_len;
 245         if (flags & WSC_FLAGS_LF)
 246                 plen += 2;
 247         resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 248                              EAP_CODE_RESPONSE, id);
 249         if (resp == NULL)
 250                 return NULL;
 251
 252         wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
 253         wpabuf_put_u8(resp, flags); /* Flags */
 254         if (flags & WSC_FLAGS_LF)
 255                 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
 256
 257         wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
 258                         send_len);
 259         data->out_used += send_len;
 260
 261         ret->methodState = METHOD_MAY_CONT;
 262         ret->decision = DECISION_FAIL;
 263
 264         if (data->out_used == wpabuf_len(data->out_buf)) {
 265                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 266                            "(message sent completely)",
 267                            (unsigned long) send_len);
 268                 wpabuf_free(data->out_buf);
 269                 data->out_buf = NULL;
 270                 data->out_used = 0;
 271                 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
 272                     data->out_op_code == WSC_NACK ||
 273                     data->out_op_code == WSC_Done) {
 274                         eap_wsc_state(data, FAIL);
 275                         ret->methodState = METHOD_DONE;
 276                 } else
 277                         eap_wsc_state(data, MESG);
 278         } else {
 279                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 280                            "(%lu more to send)", (unsigned long) send_len,
 281                            (unsigned long) wpabuf_len(data->out_buf) -
 282                            data->out_used);
 283                 eap_wsc_state(data, WAIT_FRAG_ACK);
 284         }
 285
 286         return resp;
 287 }
 288
 289
 290 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 291                                 const u8 *buf, size_t len, u8 op_code)
 292 {
 293         /* Process continuation of a pending message */
 294         if (op_code != data->in_op_code) {
 295                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 296                            "fragment (expected %d)",
 297                            op_code, data->in_op_code);
 298                 return -1;
 299         }
 300
 301         if (len > wpabuf_tailroom(data->in_buf)) {
 302                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 303                 eap_wsc_state(data, FAIL);
 304                 return -1;
 305         }
 306
 307         wpabuf_put_data(data->in_buf, buf, len);
 308         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
 309                    "for %lu bytes more", (unsigned long) len,
 310                    (unsigned long) wpabuf_tailroom(data->in_buf));
 311
 312         return 0;
 313 }
 314
 315
 316 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
 317                                                 struct eap_method_ret *ret,
 318                                                 u8 id, u8 flags, u8 op_code,
 319                                                 u16 message_length,
 320                                                 const u8 *buf, size_t len)
 321 {
 322         /* Process a fragment that is not the last one of the message */
 323         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 324                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
 325                            "fragmented packet");
 326                 ret->ignore = TRUE;
 327                 return NULL;
 328         }
 329
 330         if (data->in_buf == NULL) {
 331                 /* First fragment of the message */
 332                 data->in_buf = wpabuf_alloc(message_length);
 333                 if (data->in_buf == NULL) {
 334                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 335                                    "message");
 336                         ret->ignore = TRUE;
 337                         return NULL;
 338                 }
 339                 data->in_op_code = op_code;
 340                 wpabuf_put_data(data->in_buf, buf, len);
 341                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
 342                            "fragment, waiting for %lu bytes more",
 343                            (unsigned long) len,
 344                            (unsigned long) wpabuf_tailroom(data->in_buf));
 345         }
 346
 347         return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
 348 }
 349
 350
 351 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
 352                                        struct eap_method_ret *ret,
 353                                        const struct wpabuf *reqData)
 354 {
 355         struct eap_wsc_data *data = priv;
 356         const u8 *start, *pos, *end;
 357         size_t len;
 358         u8 op_code, flags, id;
 359         u16 message_length = 0;
 360         enum wps_process_res res;
 361         struct wpabuf tmpbuf;
 362
 363         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
 364                                &len);
 365         if (pos == NULL || len < 2) {
 366                 ret->ignore = TRUE;
 367                 return NULL;
 368         }
 369
 370         id = eap_get_id(reqData);
 371
 372         start = pos;
 373         end = start + len;
 374
 375         op_code = *pos++;
 376         flags = *pos++;
 377         if (flags & WSC_FLAGS_LF) {
 378                 if (end - pos < 2) {
 379                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 380                         ret->ignore = TRUE;
 381                         return NULL;
 382                 }
 383                 message_length = WPA_GET_BE16(pos);
 384                 pos += 2;
 385
 386                 if (message_length < end - pos) {
 387                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 388                                    "Length");
 389                         ret->ignore = TRUE;
 390                         return NULL;
 391                 }
 392         }
 393
 394         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 395                    "Flags 0x%x Message Length %d",
 396                    op_code, flags, message_length);
 397
 398         if (data->state == WAIT_FRAG_ACK) {
 399                 if (op_code != WSC_FRAG_ACK) {
 400                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 401                                    "in WAIT_FRAG_ACK state", op_code);
 402                         ret->ignore = TRUE;
 403                         return NULL;
 404                 }
 405                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 406                 eap_wsc_state(data, MESG);
 407                 return eap_wsc_build_msg(data, ret, id);
 408         }
 409
 410         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 411             op_code != WSC_Done && op_code != WSC_Start) {
 412                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 413                            op_code);
 414                 ret->ignore = TRUE;
 415                 return NULL;
 416         }
 417
 418         if (data->state == WAIT_START) {
 419                 if (op_code != WSC_Start) {
 420                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 421                                    "in WAIT_START state", op_code);
 422                         ret->ignore = TRUE;
 423                         return NULL;
 424                 }
 425                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
 426                 eap_wsc_state(data, MESG);
 427                 /* Start message has empty payload, skip processing */
 428                 goto send_msg;
 429         } else if (op_code == WSC_Start) {
 430                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 431                            op_code);
 432                 ret->ignore = TRUE;
 433                 return NULL;
 434         }
 435
 436         if (data->in_buf &&
 437             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 438                 ret->ignore = TRUE;
 439                 return NULL;
 440         }
 441
 442         if (flags & WSC_FLAGS_MF) {
 443                 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
 444                                                 message_length, pos,
 445                                                 end - pos);
 446         }
 447
 448         if (data->in_buf == NULL) {
 449                 /* Wrap unfragmented messages as wpabuf without extra copy */
 450                 wpabuf_set(&tmpbuf, pos, end - pos);
 451                 data->in_buf = &tmpbuf;
 452         }
 453
 454         res = wps_process_msg(data->wps, op_code, data->in_buf);
 455         switch (res) {
 456         case WPS_DONE:
 457                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 458                            "successfully - wait for EAP failure");
 459                 eap_wsc_state(data, FAIL);
 460                 break;
 461         case WPS_CONTINUE:
 462                 eap_wsc_state(data, MESG);
 463                 break;
 464         case WPS_FAILURE:
 465                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 466                 eap_wsc_state(data, FAIL);
 467                 break;
 468         }
 469
 470         if (data->in_buf != &tmpbuf)
 471                 wpabuf_free(data->in_buf);
 472         data->in_buf = NULL;
 473
 474 send_msg:
 475         if (data->out_buf == NULL) {
 476                 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
 477                 if (data->out_buf == NULL) {
 478                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
 479                                    "message from WPS");
 480                         return NULL;
 481                 }
 482                 data->out_used = 0;
 483         }
 484
 485         eap_wsc_state(data, MESG);
 486         return eap_wsc_build_msg(data, ret, id);
 487 }
 488
 489
 490 int eap_peer_wsc_register(void)
 491 {
 492         struct eap_method *eap;
 493         int ret;
 494
 495         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 496                                     EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 497                                     "WSC");
 498         if (eap == NULL)
 499                 return -1;
 500
 501         eap->init = eap_wsc_init;
 502         eap->deinit = eap_wsc_deinit;
 503         eap->process = eap_wsc_process;
 504
 505         ret = eap_peer_method_register(eap);
 506         if (ret)
 507                 eap_peer_method_free(eap);
 508         return ret;
 509 }