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