wpa_supplicant/bss.c

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