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