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         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
  90         /* TODO */
  91         return -1;
  92 }
  93
  94
  95 static int supp_set_key(void *ctx, wpa_alg alg,
  96                         const u8 *addr, int key_idx, int set_tx,
  97                         const u8 *seq, size_t seq_len,
  98                         const u8 *key, size_t key_len)
  99 {
 100         wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
 101                    "set_tx=%d)",
 102                    __func__, alg, MAC2STR(addr), key_idx, set_tx);
 103         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
 104         wpa_hexdump(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
 105         return 0;
 106 }
 107
 108
 109 static void * supp_get_network_ctx(void *ctx)
 110 {
 111         struct ibss_rsn_peer *peer = ctx;
 112         return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
 113 }
 114
 115
 116 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
 117                                    int protection_type, int key_type)
 118 {
 119         wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
 120                    "key_type=%d)",
 121                    __func__, MAC2STR(addr), protection_type, key_type);
 122         return 0;
 123 }
 124
 125
 126 static void supp_cancel_auth_timeout(void *ctx)
 127 {
 128         wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
 129 }
 130
 131
 132 int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
 133                        const u8 *psk)
 134 {
 135         struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
 136         if (ctx == NULL)
 137                 return -1;
 138
 139         ctx->ctx = peer;
 140         ctx->set_state = supp_set_state;
 141         ctx->ether_send = supp_ether_send;
 142         ctx->get_beacon_ie = supp_get_beacon_ie;
 143         ctx->alloc_eapol = supp_alloc_eapol;
 144         ctx->set_key = supp_set_key;
 145         ctx->get_network_ctx = supp_get_network_ctx;
 146         ctx->mlme_setprotection = supp_mlme_setprotection;
 147         ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
 148         peer->supp = wpa_sm_init(ctx);
 149         if (peer->supp == NULL) {
 150                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
 151                 return -1;
 152         }
 153
 154         wpa_sm_set_own_addr(peer->supp, own_addr);
 155         wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
 156         wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
 157         wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
 158         wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
 159         wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
 160         wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
 161
 162 #if 0 /* TODO? */
 163         peer->supp_ie_len = sizeof(peer->supp_ie);
 164         if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
 165                                             &peer->supp_ie_len) < 0) {
 166                 wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
 167                            " failed");
 168                 return -1;
 169         }
 170 #endif
 171
 172         wpa_sm_notify_assoc(peer->supp, peer->addr);
 173
 174         return 0;
 175 }
 176
 177
 178 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
 179                         const char *txt)
 180 {
 181         if (addr)
 182                 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
 183                            MAC2STR(addr), txt);
 184         else
 185                 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
 186 }
 187
 188
 189 static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
 190 {
 191         struct ibss_rsn *ibss_rsn = ctx;
 192         wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
 193                    __func__, MAC2STR(addr), prev_psk);
 194         if (prev_psk)
 195                 return NULL;
 196         return ibss_rsn->psk;
 197 }
 198
 199
 200 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
 201                            size_t data_len, int encrypt)
 202 {
 203         struct ibss_rsn *ibss_rsn = ctx;
 204         struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
 205
 206         wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
 207                    "encrypt=%d)",
 208                    __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
 209
 210         if (wpa_s->l2)
 211                 return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
 212                                       data_len);
 213
 214         return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
 215 }
 216
 217
 218 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
 219                                     const u8 *own_addr)
 220 {
 221         struct wpa_auth_config conf;
 222         struct wpa_auth_callbacks cb;
 223
 224         wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
 225
 226         os_memset(&conf, 0, sizeof(conf));
 227         conf.wpa = 2;
 228         conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
 229         conf.wpa_pairwise = WPA_CIPHER_CCMP;
 230         conf.rsn_pairwise = WPA_CIPHER_CCMP;
 231         conf.wpa_group = WPA_CIPHER_CCMP;
 232         conf.eapol_version = 2;
 233
 234         os_memset(&cb, 0, sizeof(cb));
 235         cb.ctx = ibss_rsn;
 236         cb.logger = auth_logger;
 237         cb.send_eapol = auth_send_eapol;
 238         cb.get_psk = auth_get_psk;
 239
 240         ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
 241         if (ibss_rsn->auth_group == NULL) {
 242                 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
 243                 return -1;
 244         }
 245
 246         return 0;
 247 }
 248
 249
 250 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
 251                               struct ibss_rsn_peer *peer)
 252 {
 253         peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
 254         if (peer->auth == NULL) {
 255                 wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
 256                 return -1;
 257         }
 258
 259         /* TODO: get peer RSN IE with Probe Request */
 260         if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
 261                                 (u8 *) "\x30\x12\x01\x00"
 262                                 "\x00\x0f\xac\x04"
 263                                 "\x01\x00\x00\x0f\xac\x04"
 264                                 "\x01\x00\x00\x0f\xac\x02", 20, NULL, 0) !=
 265             WPA_IE_OK) {
 266                 wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
 267                 return -1;
 268         }
 269
 270         wpa_auth_sm_event(peer->auth, WPA_ASSOC);
 271
 272         wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth);
 273
 274         return 0;
 275 }
 276
 277
 278 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
 279 {
 280         struct ibss_rsn_peer *peer;
 281
 282         wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
 283                    "Supplicant for peer " MACSTR, MAC2STR(addr));
 284
 285         peer = os_zalloc(sizeof(*peer));
 286         if (peer == NULL)
 287                 return -1;
 288
 289         peer->ibss_rsn = ibss_rsn;
 290         os_memcpy(peer->addr, addr, ETH_ALEN);
 291
 292         if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
 293             < 0) {
 294                 ibss_rsn_free(peer);
 295                 return -1;
 296         }
 297
 298         if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
 299                 ibss_rsn_free(peer);
 300                 return -1;
 301         }
 302
 303         peer->next = ibss_rsn->peers;
 304         ibss_rsn->peers = peer;
 305
 306         return 0;
 307 }
 308
 309
 310 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
 311 {
 312         struct ibss_rsn *ibss_rsn;
 313
 314         ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
 315         if (ibss_rsn == NULL)
 316                 return NULL;
 317         ibss_rsn->wpa_s = wpa_s;
 318
 319         if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
 320                 ibss_rsn_deinit(ibss_rsn);
 321                 return NULL;
 322         }
 323
 324         return ibss_rsn;
 325 }
 326
 327
 328 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
 329 {
 330         struct ibss_rsn_peer *peer, *prev;
 331
 332         if (ibss_rsn == NULL)
 333                 return;
 334
 335         peer = ibss_rsn->peers;
 336         while (peer) {
 337                 prev = peer;
 338                 peer = peer->next;
 339                 ibss_rsn_free(prev);
 340         }
 341
 342         wpa_deinit(ibss_rsn->auth_group);
 343         os_free(ibss_rsn);
 344
 345 }
 346
 347
 348 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
 349 {
 350         const struct ieee802_1x_hdr *hdr;
 351         const struct wpa_eapol_key *key;
 352         u16 key_info;
 353         size_t plen;
 354
 355         /* TODO: Support other EAPOL packets than just EAPOL-Key */
 356
 357         if (len < sizeof(*hdr) + sizeof(*key))
 358                 return -1;
 359
 360         hdr = (const struct ieee802_1x_hdr *) buf;
 361         key = (const struct wpa_eapol_key *) (hdr + 1);
 362         plen = be_to_host16(hdr->length);
 363
 364         if (hdr->version < EAPOL_VERSION) {
 365                 /* TODO: backwards compatibility */
 366         }
 367         if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
 368                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
 369                         "not a Key frame", hdr->type);
 370                 return -1;
 371         }
 372         if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
 373                 wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
 374                            "invalid (frame size %lu)",
 375                            (unsigned long) plen, (unsigned long) len);
 376                 return -1;
 377         }
 378
 379         if (key->type != EAPOL_KEY_TYPE_RSN) {
 380                 wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
 381                            "discarded", key->type);
 382                 return -1;
 383         }
 384
 385         key_info = WPA_GET_BE16(key->key_info);
 386
 387         return !!(key_info & WPA_KEY_INFO_ACK);
 388 }
 389
 390
 391 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
 392                                      struct ibss_rsn_peer *peer,
 393                                      const u8 *buf, size_t len)
 394 {
 395         int supp;
 396         u8 *tmp;
 397
 398         supp = ibss_rsn_eapol_dst_supp(buf, len);
 399         if (supp < 0)
 400                 return -1;
 401
 402         tmp = os_malloc(len);
 403         if (tmp == NULL)
 404                 return -1;
 405         os_memcpy(tmp, buf, len);
 406         if (supp) {
 407                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
 408                 wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
 409         } else {
 410                 wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
 411                 wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
 412         }
 413         os_free(tmp);
 414
 415         return 1;
 416 }
 417
 418
 419 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
 420                       const u8 *buf, size_t len)
 421 {
 422         struct ibss_rsn_peer *peer;
 423
 424         for (peer = ibss_rsn->peers; peer; peer = peer->next) {
 425                 if (os_memcmp(src_addr, peer->addr, ETH_ALEN) == 0)
 426                         return ibss_rsn_process_rx_eapol(ibss_rsn, peer,
 427                                                          buf, len);
 428         }
 429
 430         if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
 431                 /*
 432                  * Create new IBSS peer based on an EAPOL message from the peer
 433                  * Authenticator.
 434                  */
 435                 if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
 436                         return -1;
 437                 return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
 438                                                  buf, len);
 439         }
 440
 441         return 0;
 442 }