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         /* struct eap_wsc_data *data = ctx; */
  72
  73         wpa_printf(MSG_DEBUG, "EAP-WSC: Received new WPA/WPA2-PSK from WPS for"
  74                    " STA " MACSTR, MAC2STR(mac_addr));
  75         wpa_hexdump_key(MSG_DEBUG, "Per-device PSK", psk, psk_len);
  76
  77         /* TODO */
  78
  79         return 0;
  80 }
  81
  82
  83 static void eap_wsc_pin_needed_cb(void *ctx, const u8 *uuid_e,
  84                                   const struct wps_device_data *dev)
  85 {
  86         /* struct eap_wsc_data *data = ctx; */
  87         char uuid[40], txt[400];
  88         int len;
  89         if (uuid_bin2str(uuid_e, uuid, sizeof(uuid)))
  90                 return;
  91         wpa_printf(MSG_DEBUG, "EAP-WSC: PIN needed for E-UUID %s", uuid);
  92         len = os_snprintf(txt, sizeof(txt), "WPS-EVENT-PIN-NEEDED "
  93                           "%s " MACSTR " [%s|%s|%s|%s|%s|%d-%08X-%d]",
  94                           uuid, MAC2STR(dev->mac_addr), dev->device_name,
  95                           dev->manufacturer, dev->model_name,
  96                           dev->model_number, dev->serial_number,
  97                           dev->categ, dev->oui, dev->sub_categ);
  98         if (len > 0 && len < (int) sizeof(txt))
  99                 wpa_printf(MSG_INFO, "%s", txt);
 100 }
 101
 102
 103 static void * eap_wsc_init(struct eap_sm *sm)
 104 {
 105         struct eap_wsc_data *data;
 106         const u8 *identity;
 107         size_t identity_len;
 108         int registrar;
 109         struct wps_config cfg;
 110         const char *pos;
 111         const char *phase1;
 112         struct wps_context *wps = NULL;
 113
 114         identity = eap_get_config_identity(sm, &identity_len);
 115
 116         if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
 117             os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
 118                 registrar = 1; /* Supplicant is Registrar */
 119         else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
 120             os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
 121                 registrar = 0; /* Supplicant is Enrollee */
 122         else {
 123                 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
 124                                   identity, identity_len);
 125                 return NULL;
 126         }
 127
 128         data = os_zalloc(sizeof(*data));
 129         if (data == NULL)
 130                 return NULL;
 131         data->state = registrar ? MSG : WAIT_START;
 132         data->registrar = registrar;
 133
 134         if (registrar) {
 135                 struct wps_registrar_config rcfg;
 136
 137                 wps = os_zalloc(sizeof(*wps));
 138                 if (wps == NULL) {
 139                         os_free(data);
 140                         return NULL;
 141                 }
 142
 143                 wps->cb_ctx = data;
 144
 145                 wps->auth_types = WPS_AUTH_WPA2PSK | WPS_AUTH_WPAPSK;
 146                 wps->encr_types = WPS_ENCR_AES | WPS_ENCR_TKIP;
 147
 148                 os_memset(&rcfg, 0, sizeof(rcfg));
 149                 rcfg.new_psk_cb = eap_wsc_new_psk_cb;
 150                 rcfg.pin_needed_cb = eap_wsc_pin_needed_cb;
 151                 rcfg.cb_ctx = data;
 152
 153                 wps->registrar = wps_registrar_init(wps, &rcfg);
 154                 if (wps->registrar == NULL) {
 155                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to initialize "
 156                                    "WPS Registrar");
 157                         os_free(wps->network_key);
 158                         os_free(wps);
 159                         os_free(data);
 160                         return NULL;
 161                 }
 162
 163                 data->wps_ctx = wps;
 164         }
 165
 166         os_memset(&cfg, 0, sizeof(cfg));
 167         cfg.authenticator = 0;
 168         cfg.wps = wps;
 169         cfg.registrar = data->wps_ctx ? data->wps_ctx->registrar : NULL;
 170         cfg.enrollee_mac_addr = sm->mac_addr;
 171
 172         phase1 = eap_get_config_phase1(sm);
 173         if (phase1 == NULL) {
 174                 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
 175                            "set");
 176                 os_free(data);
 177                 return NULL;
 178         }
 179
 180         pos = os_strstr(phase1, "pin=");
 181         if (pos) {
 182                 pos += 4;
 183                 cfg.pin = (const u8 *) pos;
 184                 while (*pos != '\0' && *pos != ' ')
 185                         pos++;
 186                 cfg.pin_len = pos - (const char *) cfg.pin;
 187         } else {
 188                 pos = os_strstr(phase1, "pbc=1");
 189                 if (pos)
 190                         cfg.pbc = 1;
 191         }
 192
 193         if (cfg.pin == NULL && !cfg.pbc) {
 194                 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
 195                            "configuration data");
 196                 os_free(data);
 197                 return NULL;
 198         }
 199
 200         if (registrar && wps)
 201                 os_memcpy(wps->uuid, sm->uuid, UUID_LEN);
 202         else
 203                 cfg.uuid = sm->uuid;
 204         cfg.wps_cred_cb = sm->eapol_cb->wps_cred;
 205         cfg.cb_ctx = sm->eapol_ctx;
 206         data->wps = wps_init(&cfg);
 207         if (data->wps == NULL) {
 208                 os_free(data);
 209                 return NULL;
 210         }
 211         data->fragment_size = WSC_FRAGMENT_SIZE;
 212
 213
 214         if (registrar) {
 215                 /* Testing */
 216                 wpa_printf(MSG_INFO, "EAP-WSC: Registrar functionality not "
 217                            "yet fully supported - using test values");
 218                 u8 uuid_e[UUID_LEN];
 219                 os_memset(uuid_e, 0, UUID_LEN);
 220                 wps_registrar_add_pin(data->wps_ctx->registrar, uuid_e,
 221                                       (const u8 *) "12345670", 8);
 222         }
 223
 224         return data;
 225 }
 226
 227
 228 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
 229 {
 230         struct eap_wsc_data *data = priv;
 231         wpabuf_free(data->in_buf);
 232         wpabuf_free(data->out_buf);
 233         wps_deinit(data->wps);
 234         if (data->wps_ctx) {
 235                 wps_registrar_deinit(data->wps_ctx->registrar);
 236                 os_free(data->wps_ctx->network_key);
 237                 os_free(data->wps_ctx);
 238         }
 239         os_free(data);
 240 }
 241
 242
 243 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
 244                                          struct eap_method_ret *ret, u8 id)
 245 {
 246         struct wpabuf *resp;
 247         u8 flags;
 248         size_t send_len, plen;
 249
 250         ret->ignore = FALSE;
 251         wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
 252         ret->allowNotifications = TRUE;
 253
 254         flags = 0;
 255         send_len = wpabuf_len(data->out_buf) - data->out_used;
 256         if (2 + send_len > data->fragment_size) {
 257                 send_len = data->fragment_size - 2;
 258                 flags |= WSC_FLAGS_MF;
 259                 if (data->out_used == 0) {
 260                         flags |= WSC_FLAGS_LF;
 261                         send_len -= 2;
 262                 }
 263         }
 264         plen = 2 + send_len;
 265         if (flags & WSC_FLAGS_LF)
 266                 plen += 2;
 267         resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
 268                              EAP_CODE_RESPONSE, id);
 269         if (resp == NULL)
 270                 return NULL;
 271
 272         wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
 273         wpabuf_put_u8(resp, flags); /* Flags */
 274         if (flags & WSC_FLAGS_LF)
 275                 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
 276
 277         wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
 278                         send_len);
 279         data->out_used += send_len;
 280
 281         ret->methodState = METHOD_MAY_CONT;
 282         ret->decision = DECISION_FAIL;
 283
 284         if (data->out_used == wpabuf_len(data->out_buf)) {
 285                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 286                            "(message sent completely)",
 287                            (unsigned long) send_len);
 288                 wpabuf_free(data->out_buf);
 289                 data->out_buf = NULL;
 290                 data->out_used = 0;
 291                 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
 292                     data->out_op_code == WSC_NACK ||
 293                     data->out_op_code == WSC_Done) {
 294                         eap_wsc_state(data, FAIL);
 295                         ret->methodState = METHOD_DONE;
 296                 } else
 297                         eap_wsc_state(data, MSG);
 298         } else {
 299                 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
 300                            "(%lu more to send)", (unsigned long) send_len,
 301                            (unsigned long) wpabuf_len(data->out_buf) -
 302                            data->out_used);
 303                 eap_wsc_state(data, WAIT_FRAG_ACK);
 304         }
 305
 306         return resp;
 307 }
 308
 309
 310 static int eap_wsc_process_cont(struct eap_wsc_data *data,
 311                                 const u8 *buf, size_t len, u8 op_code)
 312 {
 313         /* Process continuation of a pending message */
 314         if (op_code != data->in_op_code) {
 315                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
 316                            "fragment (expected %d)",
 317                            op_code, data->in_op_code);
 318                 return -1;
 319         }
 320
 321         if (len > wpabuf_tailroom(data->in_buf)) {
 322                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
 323                 eap_wsc_state(data, FAIL);
 324                 return -1;
 325         }
 326
 327         wpabuf_put_data(data->in_buf, buf, len);
 328         wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
 329                    "for %lu bytes more", (unsigned long) len,
 330                    (unsigned long) wpabuf_tailroom(data->in_buf));
 331
 332         return 0;
 333 }
 334
 335
 336 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
 337                                                 struct eap_method_ret *ret,
 338                                                 u8 id, u8 flags, u8 op_code,
 339                                                 u16 message_length,
 340                                                 const u8 *buf, size_t len)
 341 {
 342         /* Process a fragment that is not the last one of the message */
 343         if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
 344                 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
 345                            "fragmented packet");
 346                 ret->ignore = TRUE;
 347                 return NULL;
 348         }
 349
 350         if (data->in_buf == NULL) {
 351                 /* First fragment of the message */
 352                 data->in_buf = wpabuf_alloc(message_length);
 353                 if (data->in_buf == NULL) {
 354                         wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
 355                                    "message");
 356                         ret->ignore = TRUE;
 357                         return NULL;
 358                 }
 359                 data->in_op_code = op_code;
 360                 wpabuf_put_data(data->in_buf, buf, len);
 361                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
 362                            "fragment, waiting for %lu bytes more",
 363                            (unsigned long) len,
 364                            (unsigned long) wpabuf_tailroom(data->in_buf));
 365         }
 366
 367         return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
 368 }
 369
 370
 371 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
 372                                        struct eap_method_ret *ret,
 373                                        const struct wpabuf *reqData)
 374 {
 375         struct eap_wsc_data *data = priv;
 376         const u8 *start, *pos, *end;
 377         size_t len;
 378         u8 op_code, flags, id;
 379         u16 message_length = 0;
 380         enum wps_process_res res;
 381         struct wpabuf tmpbuf;
 382
 383         pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
 384                                &len);
 385         if (pos == NULL || len < 2) {
 386                 ret->ignore = TRUE;
 387                 return NULL;
 388         }
 389
 390         id = eap_get_id(reqData);
 391
 392         start = pos;
 393         end = start + len;
 394
 395         op_code = *pos++;
 396         flags = *pos++;
 397         if (flags & WSC_FLAGS_LF) {
 398                 if (end - pos < 2) {
 399                         wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
 400                         ret->ignore = TRUE;
 401                         return NULL;
 402                 }
 403                 message_length = WPA_GET_BE16(pos);
 404                 pos += 2;
 405
 406                 if (message_length < end - pos) {
 407                         wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
 408                                    "Length");
 409                         ret->ignore = TRUE;
 410                         return NULL;
 411                 }
 412         }
 413
 414         wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
 415                    "Flags 0x%x Message Length %d",
 416                    op_code, flags, message_length);
 417
 418         if (data->state == WAIT_FRAG_ACK) {
 419                 if (op_code != WSC_FRAG_ACK) {
 420                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 421                                    "in WAIT_FRAG_ACK state", op_code);
 422                         ret->ignore = TRUE;
 423                         return NULL;
 424                 }
 425                 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
 426                 eap_wsc_state(data, MSG);
 427                 return eap_wsc_build_msg(data, ret, id);
 428         }
 429
 430         if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
 431             op_code != WSC_Done && op_code != WSC_Start) {
 432                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 433                            op_code);
 434                 ret->ignore = TRUE;
 435                 return NULL;
 436         }
 437
 438         if (data->state == WAIT_START) {
 439                 if (op_code != WSC_Start) {
 440                         wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
 441                                    "in WAIT_START state", op_code);
 442                         ret->ignore = TRUE;
 443                         return NULL;
 444                 }
 445                 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
 446                 eap_wsc_state(data, MSG);
 447                 /* Start message has empty payload, skip processing */
 448                 goto send_msg;
 449         } else if (op_code == WSC_Start) {
 450                 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
 451                            op_code);
 452                 ret->ignore = TRUE;
 453                 return NULL;
 454         }
 455
 456         if (data->in_buf &&
 457             eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
 458                 ret->ignore = TRUE;
 459                 return NULL;
 460         }
 461
 462         if (flags & WSC_FLAGS_MF) {
 463                 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
 464                                                 message_length, pos,
 465                                                 end - pos);
 466         }
 467
 468         if (data->in_buf == NULL) {
 469                 /* Wrap unfragmented messages as wpabuf without extra copy */
 470                 wpabuf_set(&tmpbuf, pos, end - pos);
 471                 data->in_buf = &tmpbuf;
 472         }
 473
 474         res = wps_process_msg(data->wps, op_code, data->in_buf);
 475         switch (res) {
 476         case WPS_DONE:
 477                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
 478                            "successfully - wait for EAP failure");
 479                 eap_wsc_state(data, FAIL);
 480                 break;
 481         case WPS_CONTINUE:
 482                 eap_wsc_state(data, MSG);
 483                 break;
 484         case WPS_FAILURE:
 485                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
 486                 eap_wsc_state(data, FAIL);
 487                 break;
 488         case WPS_PENDING:
 489                 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing pending");
 490                 ret->ignore = TRUE;
 491                 if (data->in_buf == &tmpbuf)
 492                         data->in_buf = NULL;
 493                 return NULL;
 494         }
 495
 496         if (data->in_buf != &tmpbuf)
 497                 wpabuf_free(data->in_buf);
 498         data->in_buf = NULL;
 499
 500 send_msg:
 501         if (data->out_buf == NULL) {
 502                 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
 503                 if (data->out_buf == NULL) {
 504                         wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
 505                                    "message from WPS");
 506                         return NULL;
 507                 }
 508                 data->out_used = 0;
 509         }
 510
 511         eap_wsc_state(data, MSG);
 512         return eap_wsc_build_msg(data, ret, id);
 513 }
 514
 515
 516 int eap_peer_wsc_register(void)
 517 {
 518         struct eap_method *eap;
 519         int ret;
 520
 521         eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
 522                                     EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
 523                                     "WSC");
 524         if (eap == NULL)
 525                 return -1;
 526
 527         eap->init = eap_wsc_init;
 528         eap->deinit = eap_wsc_deinit;
 529         eap->process = eap_wsc_process;
 530
 531         ret = eap_peer_method_register(eap);
 532         if (ret)
 533                 eap_peer_method_free(eap);
 534         return ret;
 535 }