wpa_supplicant/bss.c

   1 /*
   2  * BSS table
   3  * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "utils/includes.h"
  10
  11 #include "utils/common.h"
  12 #include "utils/eloop.h"
  13 #include "common/ieee802_11_defs.h"
  14 #include "drivers/driver.h"
  15 #include "wpa_supplicant_i.h"
  16 #include "config.h"
  17 #include "notify.h"
  18 #include "scan.h"
  19 #include "bss.h"
  20
  21
  22 /**
  23  * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
  24  */
  25 #define WPA_BSS_EXPIRATION_PERIOD 10
  26
  27 #define WPA_BSS_FREQ_CHANGED_FLAG       BIT(0)
  28 #define WPA_BSS_SIGNAL_CHANGED_FLAG     BIT(1)
  29 #define WPA_BSS_PRIVACY_CHANGED_FLAG    BIT(2)
  30 #define WPA_BSS_MODE_CHANGED_FLAG       BIT(3)
  31 #define WPA_BSS_WPAIE_CHANGED_FLAG      BIT(4)
  32 #define WPA_BSS_RSNIE_CHANGED_FLAG      BIT(5)
  33 #define WPA_BSS_WPS_CHANGED_FLAG        BIT(6)
  34 #define WPA_BSS_RATES_CHANGED_FLAG      BIT(7)
  35 #define WPA_BSS_IES_CHANGED_FLAG        BIT(8)
  36
  37
  38 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
  39 {
  40         dl_list_del(&bss->list);
  41         dl_list_del(&bss->list_id);
  42         wpa_s->num_bss--;
  43         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
  44                 " SSID '%s'", bss->id, MAC2STR(bss->bssid),
  45                 wpa_ssid_txt(bss->ssid, bss->ssid_len));
  46         wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
  47 #ifdef CONFIG_INTERWORKING
  48         wpabuf_free(bss->anqp_venue_name);
  49         wpabuf_free(bss->anqp_network_auth_type);
  50         wpabuf_free(bss->anqp_roaming_consortium);
  51         wpabuf_free(bss->anqp_ip_addr_type_availability);
  52         wpabuf_free(bss->anqp_nai_realm);
  53         wpabuf_free(bss->anqp_3gpp);
  54         wpabuf_free(bss->anqp_domain_name);
  55 #endif /* CONFIG_INTERWORKING */
  56         os_free(bss);
  57 }
  58
  59
  60 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
  61                              const u8 *ssid, size_t ssid_len)
  62 {
  63         struct wpa_bss *bss;
  64         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
  65                 return NULL;
  66         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
  67                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
  68                     bss->ssid_len == ssid_len &&
  69                     os_memcmp(bss->ssid, ssid, ssid_len) == 0)
  70                         return bss;
  71         }
  72         return NULL;
  73 }
  74
  75
  76 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
  77 {
  78         os_time_t usec;
  79
  80         dst->flags = src->flags;
  81         os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
  82         dst->freq = src->freq;
  83         dst->beacon_int = src->beacon_int;
  84         dst->caps = src->caps;
  85         dst->qual = src->qual;
  86         dst->noise = src->noise;
  87         dst->level = src->level;
  88         dst->tsf = src->tsf;
  89
  90         os_get_time(&dst->last_update);
  91         dst->last_update.sec -= src->age / 1000;
  92         usec = (src->age % 1000) * 1000;
  93         if (dst->last_update.usec < usec) {
  94                 dst->last_update.sec--;
  95                 dst->last_update.usec += 1000000;
  96         }
  97         dst->last_update.usec -= usec;
  98 }
  99
 100
 101 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 102 {
 103         struct wpa_ssid *ssid;
 104
 105         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 106                 if (ssid->ssid == NULL || ssid->ssid_len == 0)
 107                         continue;
 108                 if (ssid->ssid_len == bss->ssid_len &&
 109                     os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
 110                         return 1;
 111         }
 112
 113         return 0;
 114 }
 115
 116
 117 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
 118 {
 119         struct wpa_bss *bss;
 120
 121         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 122                 if (!wpa_bss_known(wpa_s, bss)) {
 123                         wpa_bss_remove(wpa_s, bss);
 124                         return 0;
 125                 }
 126         }
 127
 128         return -1;
 129 }
 130
 131
 132 static void wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
 133 {
 134         /*
 135          * Remove the oldest entry that does not match with any configured
 136          * network.
 137          */
 138         if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
 139                 return;
 140
 141         /*
 142          * Remove the oldest entry since no better candidate for removal was
 143          * found.
 144          */
 145         wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
 146                                             struct wpa_bss, list));
 147 }
 148
 149
 150 static void wpa_bss_add(struct wpa_supplicant *wpa_s,
 151                         const u8 *ssid, size_t ssid_len,
 152                         struct wpa_scan_res *res)
 153 {
 154         struct wpa_bss *bss;
 155
 156         bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
 157         if (bss == NULL)
 158                 return;
 159         bss->id = wpa_s->bss_next_id++;
 160         bss->last_update_idx = wpa_s->bss_update_idx;
 161         wpa_bss_copy_res(bss, res);
 162         os_memcpy(bss->ssid, ssid, ssid_len);
 163         bss->ssid_len = ssid_len;
 164         bss->ie_len = res->ie_len;
 165         bss->beacon_ie_len = res->beacon_ie_len;
 166         os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 167
 168         dl_list_add_tail(&wpa_s->bss, &bss->list);
 169         dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
 170         wpa_s->num_bss++;
 171         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
 172                 " SSID '%s'",
 173                 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
 174         wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
 175         if (wpa_s->num_bss > wpa_s->conf->bss_max_count)
 176                 wpa_bss_remove_oldest(wpa_s);
 177 }
 178
 179
 180 static int are_ies_equal(const struct wpa_bss *old,
 181                          const struct wpa_scan_res *new, u32 ie)
 182 {
 183         const u8 *old_ie, *new_ie;
 184         struct wpabuf *old_ie_buff = NULL;
 185         struct wpabuf *new_ie_buff = NULL;
 186         int new_ie_len, old_ie_len, ret, is_multi;
 187
 188         switch (ie) {
 189         case WPA_IE_VENDOR_TYPE:
 190                 old_ie = wpa_bss_get_vendor_ie(old, ie);
 191                 new_ie = wpa_scan_get_vendor_ie(new, ie);
 192                 is_multi = 0;
 193                 break;
 194         case WPS_IE_VENDOR_TYPE:
 195                 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
 196                 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
 197                 is_multi = 1;
 198                 break;
 199         case WLAN_EID_RSN:
 200         case WLAN_EID_SUPP_RATES:
 201         case WLAN_EID_EXT_SUPP_RATES:
 202                 old_ie = wpa_bss_get_ie(old, ie);
 203                 new_ie = wpa_scan_get_ie(new, ie);
 204                 is_multi = 0;
 205                 break;
 206         default:
 207                 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
 208                 return 0;
 209         }
 210
 211         if (is_multi) {
 212                 /* in case of multiple IEs stored in buffer */
 213                 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
 214                 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
 215                 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
 216                 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
 217         } else {
 218                 /* in case of single IE */
 219                 old_ie_len = old_ie ? old_ie[1] + 2 : 0;
 220                 new_ie_len = new_ie ? new_ie[1] + 2 : 0;
 221         }
 222
 223         if (!old_ie || !new_ie)
 224                 ret = !old_ie && !new_ie;
 225         else
 226                 ret = (old_ie_len == new_ie_len &&
 227                        os_memcmp(old_ie, new_ie, old_ie_len) == 0);
 228
 229         wpabuf_free(old_ie_buff);
 230         wpabuf_free(new_ie_buff);
 231
 232         return ret;
 233 }
 234
 235
 236 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
 237                                const struct wpa_scan_res *new)
 238 {
 239         u32 changes = 0;
 240         int caps_diff = old->caps ^ new->caps;
 241
 242         if (old->freq != new->freq)
 243                 changes |= WPA_BSS_FREQ_CHANGED_FLAG;
 244
 245         if (old->level != new->level)
 246                 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
 247
 248         if (caps_diff & IEEE80211_CAP_PRIVACY)
 249                 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
 250
 251         if (caps_diff & IEEE80211_CAP_IBSS)
 252                 changes |= WPA_BSS_MODE_CHANGED_FLAG;
 253
 254         if (old->ie_len == new->ie_len &&
 255             os_memcmp(old + 1, new + 1, old->ie_len) == 0)
 256                 return changes;
 257         changes |= WPA_BSS_IES_CHANGED_FLAG;
 258
 259         if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
 260                 changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
 261
 262         if (!are_ies_equal(old, new, WLAN_EID_RSN))
 263                 changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
 264
 265         if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
 266                 changes |= WPA_BSS_WPS_CHANGED_FLAG;
 267
 268         if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
 269             !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
 270                 changes |= WPA_BSS_RATES_CHANGED_FLAG;
 271
 272         return changes;
 273 }
 274
 275
 276 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
 277                                const struct wpa_bss *bss)
 278 {
 279         if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
 280                 wpas_notify_bss_freq_changed(wpa_s, bss->id);
 281
 282         if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
 283                 wpas_notify_bss_signal_changed(wpa_s, bss->id);
 284
 285         if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
 286                 wpas_notify_bss_privacy_changed(wpa_s, bss->id);
 287
 288         if (changes & WPA_BSS_MODE_CHANGED_FLAG)
 289                 wpas_notify_bss_mode_changed(wpa_s, bss->id);
 290
 291         if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
 292                 wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
 293
 294         if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
 295                 wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
 296
 297         if (changes & WPA_BSS_WPS_CHANGED_FLAG)
 298                 wpas_notify_bss_wps_changed(wpa_s, bss->id);
 299
 300         if (changes & WPA_BSS_IES_CHANGED_FLAG)
 301                 wpas_notify_bss_ies_changed(wpa_s, bss->id);
 302
 303         if (changes & WPA_BSS_RATES_CHANGED_FLAG)
 304                 wpas_notify_bss_rates_changed(wpa_s, bss->id);
 305 }
 306
 307
 308 static void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
 309                            struct wpa_scan_res *res)
 310 {
 311         u32 changes;
 312
 313         changes = wpa_bss_compare_res(bss, res);
 314         bss->scan_miss_count = 0;
 315         bss->last_update_idx = wpa_s->bss_update_idx;
 316         wpa_bss_copy_res(bss, res);
 317         /* Move the entry to the end of the list */
 318         dl_list_del(&bss->list);
 319         if (bss->ie_len + bss->beacon_ie_len >=
 320             res->ie_len + res->beacon_ie_len) {
 321                 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 322                 bss->ie_len = res->ie_len;
 323                 bss->beacon_ie_len = res->beacon_ie_len;
 324         } else {
 325                 struct wpa_bss *nbss;
 326                 struct dl_list *prev = bss->list_id.prev;
 327                 dl_list_del(&bss->list_id);
 328                 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
 329                                   res->beacon_ie_len);
 330                 if (nbss) {
 331                         bss = nbss;
 332                         os_memcpy(bss + 1, res + 1,
 333                                   res->ie_len + res->beacon_ie_len);
 334                         bss->ie_len = res->ie_len;
 335                         bss->beacon_ie_len = res->beacon_ie_len;
 336                 }
 337                 dl_list_add(prev, &bss->list_id);
 338         }
 339         dl_list_add_tail(&wpa_s->bss, &bss->list);
 340
 341         notify_bss_changes(wpa_s, changes, bss);
 342 }
 343
 344
 345 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 346 {
 347         return bss == wpa_s->current_bss ||
 348                 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
 349                 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
 350 }
 351
 352
 353 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
 354 {
 355         wpa_s->bss_update_idx++;
 356         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
 357                 wpa_s->bss_update_idx);
 358 }
 359
 360
 361 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
 362                              struct wpa_scan_res *res)
 363 {
 364         const u8 *ssid, *p2p;
 365         struct wpa_bss *bss;
 366
 367         ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
 368         if (ssid == NULL) {
 369                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
 370                         MACSTR, MAC2STR(res->bssid));
 371                 return;
 372         }
 373         if (ssid[1] > 32) {
 374                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
 375                         MACSTR, MAC2STR(res->bssid));
 376                 return;
 377         }
 378
 379         p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
 380         if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
 381             os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
 382                 return; /* Skip P2P listen discovery results here */
 383
 384         /* TODO: add option for ignoring BSSes we are not interested in
 385          * (to save memory) */
 386         bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
 387         if (bss == NULL)
 388                 wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
 389         else
 390                 wpa_bss_update(wpa_s, bss, res);
 391 }
 392
 393
 394 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
 395                                     const struct scan_info *info)
 396 {
 397         int found;
 398         size_t i;
 399
 400         if (info == NULL)
 401                 return 1;
 402
 403         if (info->num_freqs) {
 404                 found = 0;
 405                 for (i = 0; i < info->num_freqs; i++) {
 406                         if (bss->freq == info->freqs[i]) {
 407                                 found = 1;
 408                                 break;
 409                         }
 410                 }
 411                 if (!found)
 412                         return 0;
 413         }
 414
 415         if (info->num_ssids) {
 416                 found = 0;
 417                 for (i = 0; i < info->num_ssids; i++) {
 418                         const struct wpa_driver_scan_ssid *s = &info->ssids[i];
 419                         if ((s->ssid == NULL || s->ssid_len == 0) ||
 420                             (s->ssid_len == bss->ssid_len &&
 421                              os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
 422                              0)) {
 423                                 found = 1;
 424                                 break;
 425                         }
 426                 }
 427                 if (!found)
 428                         return 0;
 429         }
 430
 431         return 1;
 432 }
 433
 434
 435 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
 436                         int new_scan)
 437 {
 438         struct wpa_bss *bss, *n;
 439
 440         if (!new_scan)
 441                 return; /* do not expire entries without new scan */
 442
 443         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 444                 if (wpa_bss_in_use(wpa_s, bss))
 445                         continue;
 446                 if (!wpa_bss_included_in_scan(bss, info))
 447                         continue; /* expire only BSSes that were scanned */
 448                 if (bss->last_update_idx < wpa_s->bss_update_idx)
 449                         bss->scan_miss_count++;
 450                 if (bss->scan_miss_count >=
 451                     wpa_s->conf->bss_expiration_scan_count) {
 452                         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
 453                                 "no match in scan", bss->id);
 454                         wpa_bss_remove(wpa_s, bss);
 455                 }
 456         }
 457 }
 458
 459
 460 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
 461 {
 462         struct wpa_bss *bss, *n;
 463         struct os_time t;
 464
 465         if (dl_list_empty(&wpa_s->bss))
 466                 return;
 467
 468         os_get_time(&t);
 469         t.sec -= age;
 470
 471         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 472                 if (wpa_bss_in_use(wpa_s, bss))
 473                         continue;
 474
 475                 if (os_time_before(&bss->last_update, &t)) {
 476                         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
 477                                 "age", bss->id);
 478                         wpa_bss_remove(wpa_s, bss);
 479                 } else
 480                         break;
 481         }
 482 }
 483
 484
 485 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
 486 {
 487         struct wpa_supplicant *wpa_s = eloop_ctx;
 488
 489         wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age);
 490         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 491                                wpa_bss_timeout, wpa_s, NULL);
 492 }
 493
 494
 495 int wpa_bss_init(struct wpa_supplicant *wpa_s)
 496 {
 497         dl_list_init(&wpa_s->bss);
 498         dl_list_init(&wpa_s->bss_id);
 499         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 500                                wpa_bss_timeout, wpa_s, NULL);
 501         return 0;
 502 }
 503
 504
 505 void wpa_bss_flush(struct wpa_supplicant *wpa_s)
 506 {
 507         struct wpa_bss *bss, *n;
 508
 509         if (wpa_s->bss.next == NULL)
 510                 return; /* BSS table not yet initialized */
 511
 512         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 513                 if (wpa_bss_in_use(wpa_s, bss))
 514                         continue;
 515                 wpa_bss_remove(wpa_s, bss);
 516         }
 517 }
 518
 519
 520 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
 521 {
 522         eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
 523         wpa_bss_flush(wpa_s);
 524 }
 525
 526
 527 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
 528                                    const u8 *bssid)
 529 {
 530         struct wpa_bss *bss;
 531         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
 532                 return NULL;
 533         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 534                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
 535                         return bss;
 536         }
 537         return NULL;
 538 }
 539
 540
 541 #ifdef CONFIG_P2P
 542 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
 543                                           const u8 *dev_addr)
 544 {
 545         struct wpa_bss *bss;
 546         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 547                 u8 addr[ETH_ALEN];
 548                 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
 549                                        addr) == 0 &&
 550                     os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
 551                         return bss;
 552         }
 553         return NULL;
 554 }
 555 #endif /* CONFIG_P2P */
 556
 557
 558 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
 559 {
 560         struct wpa_bss *bss;
 561         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 562                 if (bss->id == id)
 563                         return bss;
 564         }
 565         return NULL;
 566 }
 567
 568
 569 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
 570 {
 571         const u8 *end, *pos;
 572
 573         pos = (const u8 *) (bss + 1);
 574         end = pos + bss->ie_len;
 575
 576         while (pos + 1 < end) {
 577                 if (pos + 2 + pos[1] > end)
 578                         break;
 579                 if (pos[0] == ie)
 580                         return pos;
 581                 pos += 2 + pos[1];
 582         }
 583
 584         return NULL;
 585 }
 586
 587
 588 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
 589 {
 590         const u8 *end, *pos;
 591
 592         pos = (const u8 *) (bss + 1);
 593         end = pos + bss->ie_len;
 594
 595         while (pos + 1 < end) {
 596                 if (pos + 2 + pos[1] > end)
 597                         break;
 598                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 599                     vendor_type == WPA_GET_BE32(&pos[2]))
 600                         return pos;
 601                 pos += 2 + pos[1];
 602         }
 603
 604         return NULL;
 605 }
 606
 607
 608 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
 609                                             u32 vendor_type)
 610 {
 611         struct wpabuf *buf;
 612         const u8 *end, *pos;
 613
 614         buf = wpabuf_alloc(bss->ie_len);
 615         if (buf == NULL)
 616                 return NULL;
 617
 618         pos = (const u8 *) (bss + 1);
 619         end = pos + bss->ie_len;
 620
 621         while (pos + 1 < end) {
 622                 if (pos + 2 + pos[1] > end)
 623                         break;
 624                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 625                     vendor_type == WPA_GET_BE32(&pos[2]))
 626                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
 627                 pos += 2 + pos[1];
 628         }
 629
 630         if (wpabuf_len(buf) == 0) {
 631                 wpabuf_free(buf);
 632                 buf = NULL;
 633         }
 634
 635         return buf;
 636 }
 637
 638
 639 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
 640 {
 641         int rate = 0;
 642         const u8 *ie;
 643         int i;
 644
 645         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 646         for (i = 0; ie && i < ie[1]; i++) {
 647                 if ((ie[i + 2] & 0x7f) > rate)
 648                         rate = ie[i + 2] & 0x7f;
 649         }
 650
 651         ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 652         for (i = 0; ie && i < ie[1]; i++) {
 653                 if ((ie[i + 2] & 0x7f) > rate)
 654                         rate = ie[i + 2] & 0x7f;
 655         }
 656
 657         return rate;
 658 }
 659
 660
 661 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
 662 {
 663         const u8 *ie, *ie2;
 664         int i, j;
 665         unsigned int len;
 666         u8 *r;
 667
 668         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 669         ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 670
 671         len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
 672
 673         r = os_malloc(len);
 674         if (!r)
 675                 return -1;
 676
 677         for (i = 0; ie && i < ie[1]; i++)
 678                 r[i] = ie[i + 2] & 0x7f;
 679
 680         for (j = 0; ie2 && j < ie2[1]; j++)
 681                 r[i + j] = ie2[j + 2] & 0x7f;
 682
 683         *rates = r;
 684         return len;
 685 }