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 int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
  35                            size_t len)
  36 {
  37         struct ibss_rsn_peer *peer = ctx;
  38         struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
  39
  40         wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
  41                    "len=%lu)",
  42                    __func__, MAC2STR(dest), proto, (unsigned long) len);
  43
  44         if (wpa_s->l2)
  45                 return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
  46
  47         return wpa_drv_send_eapol(wpa_s, dest, proto, buf, len);
  48 }
  49
  50
  51 static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
  52                              u16 data_len, size_t *msg_len, void **data_pos)
  53 {
  54         struct ieee802_1x_hdr *hdr;
  55
  56         wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
  57                    __func__, type, data_len);
  58
  59         *msg_len = sizeof(*hdr) + data_len;
  60         hdr = os_malloc(*msg_len);
  61         if (hdr == NULL)
  62                 return NULL;
  63
  64         hdr->version = 2;
  65         hdr->type = type;
  66         hdr->length = host_to_be16(data_len);
  67
  68         if (data)
  69                 os_memcpy(hdr + 1, data, data_len);
  70         else
  71                 os_memset(hdr + 1, 0, data_len);
  72
  73         if (data_pos)
  74                 *data_pos = hdr + 1;
  75
  76         return (u8 *) hdr;
  77 }
  78
  79
  80 static int supp_get_beacon_ie(void *ctx)
  81 {
  82         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
  83         /* TODO */
  84         return -1;
  85 }
  86
  87
  88 static int supp_set_key(void *ctx, wpa_alg alg,
  89                         const u8 *addr, int key_idx, int set_tx,
  90                         const u8 *seq, size_t seq_len,
  91                         const u8 *key, size_t key_len)
  92 {
  93         wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
  94                    "set_tx=%d)",
  95                    __func__, alg, MAC2STR(addr), key_idx, set_tx);
  96         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
  97         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
  98         return 0;
  99 }
 100
 101
 102 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
 103                                    int protection_type, int key_type)
 104 {
 105         wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
 106                    "key_type=%d)",
 107                    __func__, MAC2STR(addr), protection_type, key_type);
 108         return 0;
 109 }
 110
 111
 112 static void supp_cancel_auth_timeout(void *ctx)
 113 {
 114         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
 115 }
 116
 117
 118 int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
 119                        const u8 *psk)
 120 {
 121         struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
 122         if (ctx == NULL)
 123                 return -1;
 124
 125         ctx->ctx = peer;
 126         ctx->ether_send = supp_ether_send;
 127         ctx->get_beacon_ie = supp_get_beacon_ie;
 128         ctx->alloc_eapol = supp_alloc_eapol;
 129         ctx->set_key = supp_set_key;
 130         ctx->mlme_setprotection = supp_mlme_setprotection;
 131         ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
 132         peer->supp = wpa_sm_init(ctx);
 133         if (peer->supp == NULL) {
 134                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
 135                 return -1;
 136         }
 137
 138         wpa_sm_set_own_addr(peer->supp, own_addr);
 139         wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
 140         wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
 141         wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
 142         wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
 143         wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
 144         wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
 145
 146 #if 0 /* TODO? */
 147         peer->supp_ie_len = sizeof(peer->supp_ie);
 148         if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
 149                                             &peer->supp_ie_len) < 0) {
 150                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
 151                            " failed");
 152                 return -1;
 153         }
 154 #endif
 155
 156         wpa_sm_notify_assoc(peer->supp, peer->addr);
 157
 158         return 0;
 159 }
 160
 161
 162 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
 163                         const char *txt)
 164 {
 165         if (addr)
 166                 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
 167                            MAC2STR(addr), txt);
 168         else
 169                 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
 170 }
 171
 172
 173 static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
 174 {
 175         struct ibss_rsn *ibss_rsn = ctx;
 176         wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
 177                    __func__, MAC2STR(addr), prev_psk);
 178         if (prev_psk)
 179                 return NULL;
 180         return ibss_rsn->psk;
 181 }
 182
 183
 184 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
 185                            size_t data_len, int encrypt)
 186 {
 187         struct ibss_rsn *ibss_rsn = ctx;
 188         struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
 189
 190         wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
 191                    "encrypt=%d)",
 192                    __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
 193
 194         if (wpa_s->l2)
 195                 return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
 196                                       data_len);
 197
 198         return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
 199 }
 200
 201
 202 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
 203                                     const u8 *own_addr)
 204 {
 205         struct wpa_auth_config conf;
 206         struct wpa_auth_callbacks cb;
 207
 208         wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
 209
 210         os_memset(&conf, 0, sizeof(conf));
 211         conf.wpa = 2;
 212         conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
 213         conf.wpa_pairwise = WPA_CIPHER_CCMP;
 214         conf.rsn_pairwise = WPA_CIPHER_CCMP;
 215         conf.wpa_group = WPA_CIPHER_CCMP;
 216         conf.eapol_version = 2;
 217
 218         os_memset(&cb, 0, sizeof(cb));
 219         cb.ctx = ibss_rsn;
 220         cb.logger = auth_logger;
 221         cb.send_eapol = auth_send_eapol;
 222         cb.get_psk = auth_get_psk;
 223
 224         ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
 225         if (ibss_rsn->auth_group == NULL) {
 226                 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
 227                 return -1;
 228         }
 229
 230         return 0;
 231 }
 232
 233
 234 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
 235                               struct ibss_rsn_peer *peer)
 236 {
 237         peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
 238         if (peer->auth == NULL) {
 239                 wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
 240                 return -1;
 241         }
 242
 243         /* TODO: get peer RSN IE with Probe Request */
 244         if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
 245                                 (u8 *) "\x30\x12\x01\x00"
 246                                 "\x00\x0f\xac\x04"
 247                                 "\x01\x00\x00\x0f\xac\x04"
 248                                 "\x01\x00\x00\x0f\xac\x02", 20, NULL, 0) !=
 249             WPA_IE_OK) {
 250                 wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
 251                 return -1;
 252         }
 253
 254         wpa_auth_sm_event(peer->auth, WPA_ASSOC);
 255
 256         wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth);
 257
 258         return 0;
 259 }
 260
 261
 262 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
 263 {
 264         struct ibss_rsn_peer *peer;
 265
 266         wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
 267                    "Supplicant for peer " MACSTR, MAC2STR(addr));
 268
 269         peer = os_zalloc(sizeof(*peer));
 270         if (peer == NULL)
 271                 return -1;
 272
 273         peer->ibss_rsn = ibss_rsn;
 274         os_memcpy(peer->addr, addr, ETH_ALEN);
 275
 276         if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
 277             < 0) {
 278                 ibss_rsn_free(peer);
 279                 return -1;
 280         }
 281
 282         if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
 283                 ibss_rsn_free(peer);
 284                 return -1;
 285         }
 286
 287         peer->next = ibss_rsn->peers;
 288         ibss_rsn->peers = peer;
 289
 290         return 0;
 291 }
 292
 293
 294 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
 295 {
 296         struct ibss_rsn *ibss_rsn;
 297
 298         ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
 299         if (ibss_rsn == NULL)
 300                 return NULL;
 301         ibss_rsn->wpa_s = wpa_s;
 302
 303         if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
 304                 ibss_rsn_deinit(ibss_rsn);
 305                 return NULL;
 306         }
 307
 308         return ibss_rsn;
 309 }
 310
 311
 312 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
 313 {
 314         struct ibss_rsn_peer *peer, *prev;
 315
 316         if (ibss_rsn == NULL)
 317                 return;
 318
 319         peer = ibss_rsn->peers;
 320         while (peer) {
 321                 prev = peer;
 322                 peer = peer->next;
 323                 ibss_rsn_free(prev);
 324         }
 325
 326         wpa_deinit(ibss_rsn->auth_group);
 327         os_free(ibss_rsn);
 328
 329 }
 330
 331
 332 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
 333 {
 334         const struct ieee802_1x_hdr *hdr;
 335         const struct wpa_eapol_key *key;
 336         u16 key_info;
 337         size_t plen;
 338
 339         /* TODO: Support other EAPOL packets than just EAPOL-Key */
 340
 341         if (len < sizeof(*hdr) + sizeof(*key))
 342                 return -1;
 343
 344         hdr = (const struct ieee802_1x_hdr *) buf;
 345         key = (const struct wpa_eapol_key *) (hdr + 1);
 346         plen = be_to_host16(hdr->length);
 347
 348         if (hdr->version < EAPOL_VERSION) {
 349                 /* TODO: backwards compatibility */
 350         }
 351         if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
 352                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
 353                         "not a Key frame", hdr->type);
 354                 return -1;
 355         }
 356         if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
 357                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
 358                            "invalid (frame size %lu)",
 359                            (unsigned long) plen, (unsigned long) len);
 360                 return -1;
 361         }
 362
 363         if (key->type != EAPOL_KEY_TYPE_RSN) {
 364                 wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
 365                            "discarded", key->type);
 366                 return -1;
 367         }
 368
 369         key_info = WPA_GET_BE16(key->key_info);
 370
 371         return !!(key_info & WPA_KEY_INFO_ACK);
 372 }
 373
 374
 375 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
 376                                      struct ibss_rsn_peer *peer,
 377                                      const u8 *buf, size_t len)
 378 {
 379         int supp;
 380         u8 *tmp;
 381
 382         supp = ibss_rsn_eapol_dst_supp(buf, len);
 383         if (supp < 0)
 384                 return -1;
 385
 386         tmp = os_malloc(len);
 387         if (tmp == NULL)
 388                 return -1;
 389         os_memcpy(tmp, buf, len);
 390         if (supp) {
 391                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
 392                 wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
 393         } else {
 394                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
 395                 wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
 396         }
 397         os_free(tmp);
 398
 399         return 1;
 400 }
 401
 402
 403 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
 404                       const u8 *buf, size_t len)
 405 {
 406         struct ibss_rsn_peer *peer;
 407
 408         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 409                 if (os_memcmp(src_addr, peer->addr, ETH_ALEN) == 0)
 410                         return ibss_rsn_process_rx_eapol(ibss_rsn, peer,
 411                                                          buf, len);
 412         }
 413
 414         if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
 415                 /*
 416                  * Create new IBSS peer based on an EAPOL message from the peer
 417                  * Authenticator.
 418                  */
 419                 if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
 420                         return -1;
 421                 return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
 422                                                  buf, len);
 423         }
 424
 425         return 0;
 426 }