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 "wpa_supplicant_i.h"
  20 #include "wpa.h"
  21 #include "wpa_ie.h"
  22 #include "../hostapd/wpa.h"
  23 #include "ibss_rsn.h"
  24
  25
  26 static void ibss_rsn_free(struct ibss_rsn_peer *peer)
  27 {
  28         wpa_auth_sta_deinit(peer->auth);
  29         wpa_sm_deinit(peer->supp);
  30         os_free(peer);
  31 }
  32
  33
  34 static void supp_set_state(void *ctx, wpa_states state)
  35 {
  36         struct ibss_rsn_peer *peer = ctx;
  37         peer->supp_state = state;
  38 }
  39
  40
  41 static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
  42                            size_t len)
  43 {
  44         struct ibss_rsn_peer *peer = ctx;
  45         struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
  46
  47         wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
  48                    "len=%lu)",
  49                    __func__, MAC2STR(dest), proto, (unsigned long) len);
  50
  51         if (wpa_s->l2)
  52                 return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
  53
  54         return wpa_drv_send_eapol(wpa_s, dest, proto, buf, len);
  55 }
  56
  57
  58 static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
  59                              u16 data_len, size_t *msg_len, void **data_pos)
  60 {
  61         struct ieee802_1x_hdr *hdr;
  62
  63         wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
  64                    __func__, type, data_len);
  65
  66         *msg_len = sizeof(*hdr) + data_len;
  67         hdr = os_malloc(*msg_len);
  68         if (hdr == NULL)
  69                 return NULL;
  70
  71         hdr->version = 2;
  72         hdr->type = type;
  73         hdr->length = host_to_be16(data_len);
  74
  75         if (data)
  76                 os_memcpy(hdr + 1, data, data_len);
  77         else
  78                 os_memset(hdr + 1, 0, data_len);
  79
  80         if (data_pos)
  81                 *data_pos = hdr + 1;
  82
  83         return (u8 *) hdr;
  84 }
  85
  86
  87 static int supp_get_beacon_ie(void *ctx)
  88 {
  89         struct ibss_rsn_peer *peer = ctx;
  90
  91         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
  92         /* TODO: get correct RSN IE */
  93         return wpa_sm_set_ap_rsn_ie(peer->supp,
  94                                     (u8 *) "\x30\x14\x01\x00"
  95                                     "\x00\x0f\xac\x04"
  96                                     "\x01\x00\x00\x0f\xac\x04"
  97                                     "\x01\x00\x00\x0f\xac\x02"
  98                                     "\x00\x00", 22);
  99 }
 100
 101
 102 static int supp_set_key(void *ctx, wpa_alg alg,
 103                         const u8 *addr, int key_idx, int set_tx,
 104                         const u8 *seq, size_t seq_len,
 105                         const u8 *key, size_t key_len)
 106 {
 107         wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
 108                    "set_tx=%d)",
 109                    __func__, alg, MAC2STR(addr), key_idx, set_tx);
 110         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
 111         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
 112         return 0;
 113 }
 114
 115
 116 static void * supp_get_network_ctx(void *ctx)
 117 {
 118         struct ibss_rsn_peer *peer = ctx;
 119         return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
 120 }
 121
 122
 123 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
 124                                    int protection_type, int key_type)
 125 {
 126         wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
 127                    "key_type=%d)",
 128                    __func__, MAC2STR(addr), protection_type, key_type);
 129         return 0;
 130 }
 131
 132
 133 static void supp_cancel_auth_timeout(void *ctx)
 134 {
 135         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
 136 }
 137
 138
 139 int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
 140                        const u8 *psk)
 141 {
 142         struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
 143         if (ctx == NULL)
 144                 return -1;
 145
 146         ctx->ctx = peer;
 147         ctx->set_state = supp_set_state;
 148         ctx->ether_send = supp_ether_send;
 149         ctx->get_beacon_ie = supp_get_beacon_ie;
 150         ctx->alloc_eapol = supp_alloc_eapol;
 151         ctx->set_key = supp_set_key;
 152         ctx->get_network_ctx = supp_get_network_ctx;
 153         ctx->mlme_setprotection = supp_mlme_setprotection;
 154         ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
 155         peer->supp = wpa_sm_init(ctx);
 156         if (peer->supp == NULL) {
 157                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
 158                 return -1;
 159         }
 160
 161         wpa_sm_set_own_addr(peer->supp, own_addr);
 162         wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
 163         wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
 164         wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
 165         wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
 166         wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
 167         wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
 168
 169         peer->supp_ie_len = sizeof(peer->supp_ie);
 170         if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
 171                                             &peer->supp_ie_len) < 0) {
 172                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
 173                            " failed");
 174                 return -1;
 175         }
 176
 177         wpa_sm_notify_assoc(peer->supp, peer->addr);
 178
 179         return 0;
 180 }
 181
 182
 183 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
 184                         const char *txt)
 185 {
 186         if (addr)
 187                 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
 188                            MAC2STR(addr), txt);
 189         else
 190                 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
 191 }
 192
 193
 194 static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
 195 {
 196         struct ibss_rsn *ibss_rsn = ctx;
 197         wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
 198                    __func__, MAC2STR(addr), prev_psk);
 199         if (prev_psk)
 200                 return NULL;
 201         return ibss_rsn->psk;
 202 }
 203
 204
 205 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
 206                            size_t data_len, int encrypt)
 207 {
 208         struct ibss_rsn *ibss_rsn = ctx;
 209         struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
 210
 211         wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
 212                    "encrypt=%d)",
 213                    __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
 214
 215         if (wpa_s->l2)
 216                 return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
 217                                       data_len);
 218
 219         return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
 220 }
 221
 222
 223 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
 224                                     const u8 *own_addr)
 225 {
 226         struct wpa_auth_config conf;
 227         struct wpa_auth_callbacks cb;
 228
 229         wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
 230
 231         os_memset(&conf, 0, sizeof(conf));
 232         conf.wpa = 2;
 233         conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
 234         conf.wpa_pairwise = WPA_CIPHER_CCMP;
 235         conf.rsn_pairwise = WPA_CIPHER_CCMP;
 236         conf.wpa_group = WPA_CIPHER_CCMP;
 237         conf.eapol_version = 2;
 238
 239         os_memset(&cb, 0, sizeof(cb));
 240         cb.ctx = ibss_rsn;
 241         cb.logger = auth_logger;
 242         cb.send_eapol = auth_send_eapol;
 243         cb.get_psk = auth_get_psk;
 244
 245         ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
 246         if (ibss_rsn->auth_group == NULL) {
 247                 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
 248                 return -1;
 249         }
 250
 251         return 0;
 252 }
 253
 254
 255 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
 256                               struct ibss_rsn_peer *peer)
 257 {
 258         peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
 259         if (peer->auth == NULL) {
 260                 wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
 261                 return -1;
 262         }
 263
 264         /* TODO: get peer RSN IE with Probe Request */
 265         if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
 266                                 (u8 *) "\x30\x14\x01\x00"
 267                                 "\x00\x0f\xac\x04"
 268                                 "\x01\x00\x00\x0f\xac\x04"
 269                                 "\x01\x00\x00\x0f\xac\x02"
 270                                 "\x00\x00", 22, NULL, 0) !=
 271             WPA_IE_OK) {
 272                 wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
 273                 return -1;
 274         }
 275
 276         wpa_auth_sm_event(peer->auth, WPA_ASSOC);
 277
 278         wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth);
 279
 280         return 0;
 281 }
 282
 283
 284 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
 285 {
 286         struct ibss_rsn_peer *peer;
 287
 288         wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
 289                    "Supplicant for peer " MACSTR, MAC2STR(addr));
 290
 291         peer = os_zalloc(sizeof(*peer));
 292         if (peer == NULL)
 293                 return -1;
 294
 295         peer->ibss_rsn = ibss_rsn;
 296         os_memcpy(peer->addr, addr, ETH_ALEN);
 297
 298         if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
 299             < 0) {
 300                 ibss_rsn_free(peer);
 301                 return -1;
 302         }
 303
 304         if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
 305                 ibss_rsn_free(peer);
 306                 return -1;
 307         }
 308
 309         peer->next = ibss_rsn->peers;
 310         ibss_rsn->peers = peer;
 311
 312         return 0;
 313 }
 314
 315
 316 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
 317 {
 318         struct ibss_rsn *ibss_rsn;
 319
 320         ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
 321         if (ibss_rsn == NULL)
 322                 return NULL;
 323         ibss_rsn->wpa_s = wpa_s;
 324
 325         if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
 326                 ibss_rsn_deinit(ibss_rsn);
 327                 return NULL;
 328         }
 329
 330         return ibss_rsn;
 331 }
 332
 333
 334 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
 335 {
 336         struct ibss_rsn_peer *peer, *prev;
 337
 338         if (ibss_rsn == NULL)
 339                 return;
 340
 341         peer = ibss_rsn->peers;
 342         while (peer) {
 343                 prev = peer;
 344                 peer = peer->next;
 345                 ibss_rsn_free(prev);
 346         }
 347
 348         wpa_deinit(ibss_rsn->auth_group);
 349         os_free(ibss_rsn);
 350
 351 }
 352
 353
 354 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
 355 {
 356         const struct ieee802_1x_hdr *hdr;
 357         const struct wpa_eapol_key *key;
 358         u16 key_info;
 359         size_t plen;
 360
 361         /* TODO: Support other EAPOL packets than just EAPOL-Key */
 362
 363         if (len < sizeof(*hdr) + sizeof(*key))
 364                 return -1;
 365
 366         hdr = (const struct ieee802_1x_hdr *) buf;
 367         key = (const struct wpa_eapol_key *) (hdr + 1);
 368         plen = be_to_host16(hdr->length);
 369
 370         if (hdr->version < EAPOL_VERSION) {
 371                 /* TODO: backwards compatibility */
 372         }
 373         if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
 374                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
 375                         "not a Key frame", hdr->type);
 376                 return -1;
 377         }
 378         if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
 379                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
 380                            "invalid (frame size %lu)",
 381                            (unsigned long) plen, (unsigned long) len);
 382                 return -1;
 383         }
 384
 385         if (key->type != EAPOL_KEY_TYPE_RSN) {
 386                 wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
 387                            "discarded", key->type);
 388                 return -1;
 389         }
 390
 391         key_info = WPA_GET_BE16(key->key_info);
 392
 393         return !!(key_info & WPA_KEY_INFO_ACK);
 394 }
 395
 396
 397 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
 398                                      struct ibss_rsn_peer *peer,
 399                                      const u8 *buf, size_t len)
 400 {
 401         int supp;
 402         u8 *tmp;
 403
 404         supp = ibss_rsn_eapol_dst_supp(buf, len);
 405         if (supp < 0)
 406                 return -1;
 407
 408         tmp = os_malloc(len);
 409         if (tmp == NULL)
 410                 return -1;
 411         os_memcpy(tmp, buf, len);
 412         if (supp) {
 413                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
 414                 wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
 415         } else {
 416                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
 417                 wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
 418         }
 419         os_free(tmp);
 420
 421         return 1;
 422 }
 423
 424
 425 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
 426                       const u8 *buf, size_t len)
 427 {
 428         struct ibss_rsn_peer *peer;
 429
 430         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 431                 if (os_memcmp(src_addr, peer->addr, ETH_ALEN) == 0)
 432                         return ibss_rsn_process_rx_eapol(ibss_rsn, peer,
 433                                                          buf, len);
 434         }
 435
 436         if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
 437                 /*
 438                  * Create new IBSS peer based on an EAPOL message from the peer
 439                  * Authenticator.
 440                  */
 441                 if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
 442                         return -1;
 443                 return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
 444                                                  buf, len);
 445         }
 446
 447         return 0;
 448 }