wpa_supplicant/ibss_rsn.c

   1 /*
   2  * wpa_supplicant - IBSS RSN
   3  * Copyright (c) 2009, 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 "l2_packet/l2_packet.h"
  19 #include "rsn_supp/wpa.h"
  20 #include "rsn_supp/wpa_ie.h"
  21 #include "ap/wpa_auth.h"
  22 #include "wpa_supplicant_i.h"
  23 #include "driver_i.h"
  24 #include "ibss_rsn.h"
  25
  26
  27 static void ibss_rsn_free(struct ibss_rsn_peer *peer)
  28 {
  29         wpa_auth_sta_deinit(peer->auth);
  30         wpa_sm_deinit(peer->supp);
  31         os_free(peer);
  32 }
  33
  34
  35 static void supp_set_state(void *ctx, enum wpa_states state)
  36 {
  37         struct ibss_rsn_peer *peer = ctx;
  38         peer->supp_state = state;
  39 }
  40
  41
  42 static enum wpa_states supp_get_state(void *ctx)
  43 {
  44         struct ibss_rsn_peer *peer = ctx;
  45         return peer->supp_state;
  46 }
  47
  48
  49 static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
  50                            size_t len)
  51 {
  52         struct ibss_rsn_peer *peer = ctx;
  53         struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
  54
  55         wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
  56                    "len=%lu)",
  57                    __func__, MAC2STR(dest), proto, (unsigned long) len);
  58
  59         if (wpa_s->l2)
  60                 return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
  61
  62         return wpa_drv_send_eapol(wpa_s, dest, proto, buf, len);
  63 }
  64
  65
  66 static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
  67                              u16 data_len, size_t *msg_len, void **data_pos)
  68 {
  69         struct ieee802_1x_hdr *hdr;
  70
  71         wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
  72                    __func__, type, data_len);
  73
  74         *msg_len = sizeof(*hdr) + data_len;
  75         hdr = os_malloc(*msg_len);
  76         if (hdr == NULL)
  77                 return NULL;
  78
  79         hdr->version = 2;
  80         hdr->type = type;
  81         hdr->length = host_to_be16(data_len);
  82
  83         if (data)
  84                 os_memcpy(hdr + 1, data, data_len);
  85         else
  86                 os_memset(hdr + 1, 0, data_len);
  87
  88         if (data_pos)
  89                 *data_pos = hdr + 1;
  90
  91         return (u8 *) hdr;
  92 }
  93
  94
  95 static int supp_get_beacon_ie(void *ctx)
  96 {
  97         struct ibss_rsn_peer *peer = ctx;
  98
  99         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
 100         /* TODO: get correct RSN IE */
 101         return wpa_sm_set_ap_rsn_ie(peer->supp,
 102                                     (u8 *) "\x30\x14\x01\x00"
 103                                     "\x00\x0f\xac\x04"
 104                                     "\x01\x00\x00\x0f\xac\x04"
 105                                     "\x01\x00\x00\x0f\xac\x02"
 106                                     "\x00\x00", 22);
 107 }
 108
 109
 110 static int supp_set_key(void *ctx, enum wpa_alg alg,
 111                         const u8 *addr, int key_idx, int set_tx,
 112                         const u8 *seq, size_t seq_len,
 113                         const u8 *key, size_t key_len)
 114 {
 115         struct ibss_rsn_peer *peer = ctx;
 116
 117         wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
 118                    "set_tx=%d)",
 119                    __func__, alg, MAC2STR(addr), key_idx, set_tx);
 120         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
 121         wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
 122
 123         if (key_idx == 0) {
 124                 /*
 125                  * In IBSS RSN, the pairwise key from the 4-way handshake
 126                  * initiated by the peer with highest MAC address is used.
 127                  */
 128                 if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
 129                               ETH_ALEN) > 0) {
 130                         wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
 131                         return 0;
 132                 }
 133         }
 134
 135         if (is_broadcast_ether_addr(addr))
 136                 addr = peer->addr;
 137         return wpa_drv_set_key(peer->ibss_rsn->wpa_s, alg, addr, key_idx,
 138                                set_tx, seq, seq_len, key, key_len);
 139 }
 140
 141
 142 static void * supp_get_network_ctx(void *ctx)
 143 {
 144         struct ibss_rsn_peer *peer = ctx;
 145         return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
 146 }
 147
 148
 149 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
 150                                    int protection_type, int key_type)
 151 {
 152         wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
 153                    "key_type=%d)",
 154                    __func__, MAC2STR(addr), protection_type, key_type);
 155         return 0;
 156 }
 157
 158
 159 static void supp_cancel_auth_timeout(void *ctx)
 160 {
 161         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
 162 }
 163
 164
 165 static void supp_deauthenticate(void * ctx, int reason_code)
 166 {
 167         wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
 168 }
 169
 170
 171 int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
 172                        const u8 *psk)
 173 {
 174         struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
 175         if (ctx == NULL)
 176                 return -1;
 177
 178         ctx->ctx = peer;
 179         ctx->msg_ctx = peer->ibss_rsn->wpa_s;
 180         ctx->set_state = supp_set_state;
 181         ctx->get_state = supp_get_state;
 182         ctx->ether_send = supp_ether_send;
 183         ctx->get_beacon_ie = supp_get_beacon_ie;
 184         ctx->alloc_eapol = supp_alloc_eapol;
 185         ctx->set_key = supp_set_key;
 186         ctx->get_network_ctx = supp_get_network_ctx;
 187         ctx->mlme_setprotection = supp_mlme_setprotection;
 188         ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
 189         ctx->deauthenticate = supp_deauthenticate;
 190         peer->supp = wpa_sm_init(ctx);
 191         if (peer->supp == NULL) {
 192                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
 193                 return -1;
 194         }
 195
 196         wpa_sm_set_own_addr(peer->supp, own_addr);
 197         wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
 198         wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
 199         wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
 200         wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
 201         wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
 202         wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
 203
 204         peer->supp_ie_len = sizeof(peer->supp_ie);
 205         if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
 206                                             &peer->supp_ie_len) < 0) {
 207                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
 208                            " failed");
 209                 return -1;
 210         }
 211
 212         wpa_sm_notify_assoc(peer->supp, peer->addr);
 213
 214         return 0;
 215 }
 216
 217
 218 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
 219                         const char *txt)
 220 {
 221         if (addr)
 222                 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
 223                            MAC2STR(addr), txt);
 224         else
 225                 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
 226 }
 227
 228
 229 static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
 230 {
 231         struct ibss_rsn *ibss_rsn = ctx;
 232         wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
 233                    __func__, MAC2STR(addr), prev_psk);
 234         if (prev_psk)
 235                 return NULL;
 236         return ibss_rsn->psk;
 237 }
 238
 239
 240 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
 241                            size_t data_len, int encrypt)
 242 {
 243         struct ibss_rsn *ibss_rsn = ctx;
 244         struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
 245
 246         wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
 247                    "encrypt=%d)",
 248                    __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
 249
 250         if (wpa_s->l2)
 251                 return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
 252                                       data_len);
 253
 254         return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
 255 }
 256
 257
 258 static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
 259                         const u8 *addr, int idx, u8 *key, size_t key_len)
 260 {
 261         struct ibss_rsn *ibss_rsn = ctx;
 262         u8 seq[6];
 263
 264         os_memset(seq, 0, sizeof(seq));
 265
 266         if (addr) {
 267                 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
 268                            " key_idx=%d)",
 269                            __func__, alg, MAC2STR(addr), idx);
 270         } else {
 271                 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
 272                            __func__, alg, idx);
 273         }
 274         wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
 275
 276         if (idx == 0) {
 277                 /*
 278                  * In IBSS RSN, the pairwise key from the 4-way handshake
 279                  * initiated by the peer with highest MAC address is used.
 280                  */
 281                 if (addr == NULL ||
 282                     os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
 283                         wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
 284                         return 0;
 285                 }
 286         }
 287
 288         return wpa_drv_set_key(ibss_rsn->wpa_s, alg, addr, idx,
 289                                1, seq, 6, key, key_len);
 290 }
 291
 292
 293 static int auth_for_each_sta(void *ctx, int (*cb)(struct wpa_state_machine *sm,
 294                                                   void *ctx),
 295                              void *cb_ctx)
 296 {
 297         struct ibss_rsn *ibss_rsn = ctx;
 298         struct ibss_rsn_peer *peer;
 299
 300         wpa_printf(MSG_DEBUG, "AUTH: for_each_sta");
 301
 302         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 303                 if (peer->auth && cb(peer->auth, cb_ctx))
 304                         return 1;
 305         }
 306
 307         return 0;
 308 }
 309
 310
 311 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
 312                                     const u8 *own_addr)
 313 {
 314         struct wpa_auth_config conf;
 315         struct wpa_auth_callbacks cb;
 316
 317         wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
 318
 319         os_memset(&conf, 0, sizeof(conf));
 320         conf.wpa = 2;
 321         conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
 322         conf.wpa_pairwise = WPA_CIPHER_CCMP;
 323         conf.rsn_pairwise = WPA_CIPHER_CCMP;
 324         conf.wpa_group = WPA_CIPHER_CCMP;
 325         conf.eapol_version = 2;
 326         conf.wpa_group_rekey = 600;
 327
 328         os_memset(&cb, 0, sizeof(cb));
 329         cb.ctx = ibss_rsn;
 330         cb.logger = auth_logger;
 331         cb.send_eapol = auth_send_eapol;
 332         cb.get_psk = auth_get_psk;
 333         cb.set_key = auth_set_key;
 334         cb.for_each_sta = auth_for_each_sta;
 335
 336         ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
 337         if (ibss_rsn->auth_group == NULL) {
 338                 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
 339                 return -1;
 340         }
 341
 342         return 0;
 343 }
 344
 345
 346 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
 347                               struct ibss_rsn_peer *peer)
 348 {
 349         peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
 350         if (peer->auth == NULL) {
 351                 wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
 352                 return -1;
 353         }
 354
 355         /* TODO: get peer RSN IE with Probe Request */
 356         if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
 357                                 (u8 *) "\x30\x14\x01\x00"
 358                                 "\x00\x0f\xac\x04"
 359                                 "\x01\x00\x00\x0f\xac\x04"
 360                                 "\x01\x00\x00\x0f\xac\x02"
 361                                 "\x00\x00", 22, NULL, 0) !=
 362             WPA_IE_OK) {
 363                 wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
 364                 return -1;
 365         }
 366
 367         if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
 368                 return -1;
 369
 370         if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
 371                 return -1;
 372
 373         return 0;
 374 }
 375
 376
 377 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
 378 {
 379         struct ibss_rsn_peer *peer;
 380
 381         if (ibss_rsn == NULL)
 382                 return -1;
 383
 384         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 385                 if (os_memcmp(addr, peer->addr, ETH_ALEN) == 0) {
 386                         wpa_printf(MSG_DEBUG, "RSN: IBSS Authenticator and "
 387                                    "Supplicant for peer " MACSTR " already "
 388                                    "running", MAC2STR(addr));
 389                         return 0;
 390                 }
 391         }
 392
 393         wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
 394                    "Supplicant for peer " MACSTR, MAC2STR(addr));
 395
 396         peer = os_zalloc(sizeof(*peer));
 397         if (peer == NULL)
 398                 return -1;
 399
 400         peer->ibss_rsn = ibss_rsn;
 401         os_memcpy(peer->addr, addr, ETH_ALEN);
 402
 403         if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
 404             < 0) {
 405                 ibss_rsn_free(peer);
 406                 return -1;
 407         }
 408
 409         if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
 410                 ibss_rsn_free(peer);
 411                 return -1;
 412         }
 413
 414         peer->next = ibss_rsn->peers;
 415         ibss_rsn->peers = peer;
 416
 417         return 0;
 418 }
 419
 420
 421 void ibss_rsn_stop(struct ibss_rsn *ibss_rsn, const u8 *peermac)
 422 {
 423         struct ibss_rsn_peer *peer, *prev;
 424
 425         if (ibss_rsn == NULL)
 426                 return;
 427
 428         if (peermac == NULL) {
 429                 /* remove all peers */
 430                 wpa_printf(MSG_DEBUG, "%s: Remove all peers", __func__);
 431                 peer = ibss_rsn->peers;
 432                 while (peer) {
 433                         prev = peer;
 434                         peer = peer->next;
 435                         ibss_rsn_free(prev);
 436                         ibss_rsn->peers = peer;
 437                 }
 438         } else {
 439                 /* remove specific peer */
 440                 wpa_printf(MSG_DEBUG, "%s: Remove specific peer " MACSTR,
 441                            __func__, MAC2STR(peermac));
 442
 443                 for (prev = NULL, peer = ibss_rsn->peers; peer != NULL;
 444                      prev = peer, peer = peer->next) {
 445                         if (os_memcmp(peermac, peer->addr, ETH_ALEN) == 0) {
 446                                 if (prev == NULL)
 447                                         ibss_rsn->peers = peer->next;
 448                                 else
 449                                         prev->next = peer->next;
 450                                 ibss_rsn_free(peer);
 451                                 wpa_printf(MSG_DEBUG, "%s: Successfully "
 452                                            "removed a specific peer",
 453                                            __func__);
 454                                 break;
 455                         }
 456                 }
 457         }
 458 }
 459
 460
 461 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
 462 {
 463         struct ibss_rsn *ibss_rsn;
 464
 465         ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
 466         if (ibss_rsn == NULL)
 467                 return NULL;
 468         ibss_rsn->wpa_s = wpa_s;
 469
 470         if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
 471                 ibss_rsn_deinit(ibss_rsn);
 472                 return NULL;
 473         }
 474
 475         return ibss_rsn;
 476 }
 477
 478
 479 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
 480 {
 481         struct ibss_rsn_peer *peer, *prev;
 482
 483         if (ibss_rsn == NULL)
 484                 return;
 485
 486         peer = ibss_rsn->peers;
 487         while (peer) {
 488                 prev = peer;
 489                 peer = peer->next;
 490                 ibss_rsn_free(prev);
 491         }
 492
 493         wpa_deinit(ibss_rsn->auth_group);
 494         os_free(ibss_rsn);
 495
 496 }
 497
 498
 499 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
 500 {
 501         const struct ieee802_1x_hdr *hdr;
 502         const struct wpa_eapol_key *key;
 503         u16 key_info;
 504         size_t plen;
 505
 506         /* TODO: Support other EAPOL packets than just EAPOL-Key */
 507
 508         if (len < sizeof(*hdr) + sizeof(*key))
 509                 return -1;
 510
 511         hdr = (const struct ieee802_1x_hdr *) buf;
 512         key = (const struct wpa_eapol_key *) (hdr + 1);
 513         plen = be_to_host16(hdr->length);
 514
 515         if (hdr->version < EAPOL_VERSION) {
 516                 /* TODO: backwards compatibility */
 517         }
 518         if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
 519                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
 520                         "not a Key frame", hdr->type);
 521                 return -1;
 522         }
 523         if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
 524                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
 525                            "invalid (frame size %lu)",
 526                            (unsigned long) plen, (unsigned long) len);
 527                 return -1;
 528         }
 529
 530         if (key->type != EAPOL_KEY_TYPE_RSN) {
 531                 wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
 532                            "discarded", key->type);
 533                 return -1;
 534         }
 535
 536         key_info = WPA_GET_BE16(key->key_info);
 537
 538         return !!(key_info & WPA_KEY_INFO_ACK);
 539 }
 540
 541
 542 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
 543                                      struct ibss_rsn_peer *peer,
 544                                      const u8 *buf, size_t len)
 545 {
 546         int supp;
 547         u8 *tmp;
 548
 549         supp = ibss_rsn_eapol_dst_supp(buf, len);
 550         if (supp < 0)
 551                 return -1;
 552
 553         tmp = os_malloc(len);
 554         if (tmp == NULL)
 555                 return -1;
 556         os_memcpy(tmp, buf, len);
 557         if (supp) {
 558                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
 559                 wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
 560         } else {
 561                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
 562                 wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
 563         }
 564         os_free(tmp);
 565
 566         return 1;
 567 }
 568
 569
 570 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
 571                       const u8 *buf, size_t len)
 572 {
 573         struct ibss_rsn_peer *peer;
 574
 575         if (ibss_rsn == NULL)
 576                 return -1;
 577
 578         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 579                 if (os_memcmp(src_addr, peer->addr, ETH_ALEN) == 0)
 580                         return ibss_rsn_process_rx_eapol(ibss_rsn, peer,
 581                                                          buf, len);
 582         }
 583
 584         if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
 585                 /*
 586                  * Create new IBSS peer based on an EAPOL message from the peer
 587                  * Authenticator.
 588                  */
 589                 if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
 590                         return -1;
 591                 return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
 592                                                  buf, len);
 593         }
 594
 595         return 0;
 596 }
 597
 598
 599 void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
 600 {
 601         if (ibss_rsn == NULL)
 602                 return;
 603         os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
 604 }