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 #ifdef CONFIG_HS20
  57         wpabuf_free(bss->hs20_operator_friendly_name);
  58         wpabuf_free(bss->hs20_wan_metrics);
  59         wpabuf_free(bss->hs20_connection_capability);
  60         wpabuf_free(bss->hs20_operating_class);
  61 #endif /* CONFIG_HS20 */
  62         os_free(bss);
  63 }
  64
  65
  66 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
  67                              const u8 *ssid, size_t ssid_len)
  68 {
  69         struct wpa_bss *bss;
  70         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
  71                 return NULL;
  72         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
  73                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
  74                     bss->ssid_len == ssid_len &&
  75                     os_memcmp(bss->ssid, ssid, ssid_len) == 0)
  76                         return bss;
  77         }
  78         return NULL;
  79 }
  80
  81
  82 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
  83 {
  84         os_time_t usec;
  85
  86         dst->flags = src->flags;
  87         os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
  88         dst->freq = src->freq;
  89         dst->beacon_int = src->beacon_int;
  90         dst->caps = src->caps;
  91         dst->qual = src->qual;
  92         dst->noise = src->noise;
  93         dst->level = src->level;
  94         dst->tsf = src->tsf;
  95
  96         os_get_time(&dst->last_update);
  97         dst->last_update.sec -= src->age / 1000;
  98         usec = (src->age % 1000) * 1000;
  99         if (dst->last_update.usec < usec) {
 100                 dst->last_update.sec--;
 101                 dst->last_update.usec += 1000000;
 102         }
 103         dst->last_update.usec -= usec;
 104 }
 105
 106
 107 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 108 {
 109         struct wpa_ssid *ssid;
 110
 111         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 112                 if (ssid->ssid == NULL || ssid->ssid_len == 0)
 113                         continue;
 114                 if (ssid->ssid_len == bss->ssid_len &&
 115                     os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
 116                         return 1;
 117         }
 118
 119         return 0;
 120 }
 121
 122
 123 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
 124 {
 125         struct wpa_bss *bss;
 126
 127         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 128                 if (!wpa_bss_known(wpa_s, bss)) {
 129                         wpa_bss_remove(wpa_s, bss);
 130                         return 0;
 131                 }
 132         }
 133
 134         return -1;
 135 }
 136
 137
 138 static void wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
 139 {
 140         /*
 141          * Remove the oldest entry that does not match with any configured
 142          * network.
 143          */
 144         if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
 145                 return;
 146
 147         /*
 148          * Remove the oldest entry since no better candidate for removal was
 149          * found.
 150          */
 151         wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
 152                                             struct wpa_bss, list));
 153 }
 154
 155
 156 static void wpa_bss_add(struct wpa_supplicant *wpa_s,
 157                         const u8 *ssid, size_t ssid_len,
 158                         struct wpa_scan_res *res)
 159 {
 160         struct wpa_bss *bss;
 161
 162         bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
 163         if (bss == NULL)
 164                 return;
 165         bss->id = wpa_s->bss_next_id++;
 166         bss->last_update_idx = wpa_s->bss_update_idx;
 167         wpa_bss_copy_res(bss, res);
 168         os_memcpy(bss->ssid, ssid, ssid_len);
 169         bss->ssid_len = ssid_len;
 170         bss->ie_len = res->ie_len;
 171         bss->beacon_ie_len = res->beacon_ie_len;
 172         os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 173
 174         dl_list_add_tail(&wpa_s->bss, &bss->list);
 175         dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
 176         wpa_s->num_bss++;
 177         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
 178                 " SSID '%s'",
 179                 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
 180         wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
 181         if (wpa_s->num_bss > wpa_s->conf->bss_max_count)
 182                 wpa_bss_remove_oldest(wpa_s);
 183 }
 184
 185
 186 static int are_ies_equal(const struct wpa_bss *old,
 187                          const struct wpa_scan_res *new, u32 ie)
 188 {
 189         const u8 *old_ie, *new_ie;
 190         struct wpabuf *old_ie_buff = NULL;
 191         struct wpabuf *new_ie_buff = NULL;
 192         int new_ie_len, old_ie_len, ret, is_multi;
 193
 194         switch (ie) {
 195         case WPA_IE_VENDOR_TYPE:
 196                 old_ie = wpa_bss_get_vendor_ie(old, ie);
 197                 new_ie = wpa_scan_get_vendor_ie(new, ie);
 198                 is_multi = 0;
 199                 break;
 200         case WPS_IE_VENDOR_TYPE:
 201                 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
 202                 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
 203                 is_multi = 1;
 204                 break;
 205         case WLAN_EID_RSN:
 206         case WLAN_EID_SUPP_RATES:
 207         case WLAN_EID_EXT_SUPP_RATES:
 208                 old_ie = wpa_bss_get_ie(old, ie);
 209                 new_ie = wpa_scan_get_ie(new, ie);
 210                 is_multi = 0;
 211                 break;
 212         default:
 213                 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
 214                 return 0;
 215         }
 216
 217         if (is_multi) {
 218                 /* in case of multiple IEs stored in buffer */
 219                 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
 220                 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
 221                 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
 222                 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
 223         } else {
 224                 /* in case of single IE */
 225                 old_ie_len = old_ie ? old_ie[1] + 2 : 0;
 226                 new_ie_len = new_ie ? new_ie[1] + 2 : 0;
 227         }
 228
 229         if (!old_ie || !new_ie)
 230                 ret = !old_ie && !new_ie;
 231         else
 232                 ret = (old_ie_len == new_ie_len &&
 233                        os_memcmp(old_ie, new_ie, old_ie_len) == 0);
 234
 235         wpabuf_free(old_ie_buff);
 236         wpabuf_free(new_ie_buff);
 237
 238         return ret;
 239 }
 240
 241
 242 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
 243                                const struct wpa_scan_res *new)
 244 {
 245         u32 changes = 0;
 246         int caps_diff = old->caps ^ new->caps;
 247
 248         if (old->freq != new->freq)
 249                 changes |= WPA_BSS_FREQ_CHANGED_FLAG;
 250
 251         if (old->level != new->level)
 252                 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
 253
 254         if (caps_diff & IEEE80211_CAP_PRIVACY)
 255                 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
 256
 257         if (caps_diff & IEEE80211_CAP_IBSS)
 258                 changes |= WPA_BSS_MODE_CHANGED_FLAG;
 259
 260         if (old->ie_len == new->ie_len &&
 261             os_memcmp(old + 1, new + 1, old->ie_len) == 0)
 262                 return changes;
 263         changes |= WPA_BSS_IES_CHANGED_FLAG;
 264
 265         if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
 266                 changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
 267
 268         if (!are_ies_equal(old, new, WLAN_EID_RSN))
 269                 changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
 270
 271         if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
 272                 changes |= WPA_BSS_WPS_CHANGED_FLAG;
 273
 274         if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
 275             !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
 276                 changes |= WPA_BSS_RATES_CHANGED_FLAG;
 277
 278         return changes;
 279 }
 280
 281
 282 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
 283                                const struct wpa_bss *bss)
 284 {
 285         if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
 286                 wpas_notify_bss_freq_changed(wpa_s, bss->id);
 287
 288         if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
 289                 wpas_notify_bss_signal_changed(wpa_s, bss->id);
 290
 291         if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
 292                 wpas_notify_bss_privacy_changed(wpa_s, bss->id);
 293
 294         if (changes & WPA_BSS_MODE_CHANGED_FLAG)
 295                 wpas_notify_bss_mode_changed(wpa_s, bss->id);
 296
 297         if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
 298                 wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
 299
 300         if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
 301                 wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
 302
 303         if (changes & WPA_BSS_WPS_CHANGED_FLAG)
 304                 wpas_notify_bss_wps_changed(wpa_s, bss->id);
 305
 306         if (changes & WPA_BSS_IES_CHANGED_FLAG)
 307                 wpas_notify_bss_ies_changed(wpa_s, bss->id);
 308
 309         if (changes & WPA_BSS_RATES_CHANGED_FLAG)
 310                 wpas_notify_bss_rates_changed(wpa_s, bss->id);
 311 }
 312
 313
 314 static void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
 315                            struct wpa_scan_res *res)
 316 {
 317         u32 changes;
 318
 319         changes = wpa_bss_compare_res(bss, res);
 320         bss->scan_miss_count = 0;
 321         bss->last_update_idx = wpa_s->bss_update_idx;
 322         wpa_bss_copy_res(bss, res);
 323         /* Move the entry to the end of the list */
 324         dl_list_del(&bss->list);
 325         if (bss->ie_len + bss->beacon_ie_len >=
 326             res->ie_len + res->beacon_ie_len) {
 327                 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 328                 bss->ie_len = res->ie_len;
 329                 bss->beacon_ie_len = res->beacon_ie_len;
 330         } else {
 331                 struct wpa_bss *nbss;
 332                 struct dl_list *prev = bss->list_id.prev;
 333                 dl_list_del(&bss->list_id);
 334                 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
 335                                   res->beacon_ie_len);
 336                 if (nbss) {
 337                         if (wpa_s->current_bss == bss)
 338                                 wpa_s->current_bss = nbss;
 339                         bss = nbss;
 340                         os_memcpy(bss + 1, res + 1,
 341                                   res->ie_len + res->beacon_ie_len);
 342                         bss->ie_len = res->ie_len;
 343                         bss->beacon_ie_len = res->beacon_ie_len;
 344                 }
 345                 dl_list_add(prev, &bss->list_id);
 346         }
 347         dl_list_add_tail(&wpa_s->bss, &bss->list);
 348
 349         notify_bss_changes(wpa_s, changes, bss);
 350 }
 351
 352
 353 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 354 {
 355         return bss == wpa_s->current_bss ||
 356                 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
 357                 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
 358 }
 359
 360
 361 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
 362 {
 363         wpa_s->bss_update_idx++;
 364         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
 365                 wpa_s->bss_update_idx);
 366 }
 367
 368
 369 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
 370                              struct wpa_scan_res *res)
 371 {
 372         const u8 *ssid, *p2p;
 373         struct wpa_bss *bss;
 374
 375         ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
 376         if (ssid == NULL) {
 377                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
 378                         MACSTR, MAC2STR(res->bssid));
 379                 return;
 380         }
 381         if (ssid[1] > 32) {
 382                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
 383                         MACSTR, MAC2STR(res->bssid));
 384                 return;
 385         }
 386
 387         p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
 388 #ifdef CONFIG_P2P
 389         if (p2p == NULL &&
 390             wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
 391                 /*
 392                  * If it's a P2P specific interface, then don't update
 393                  * the scan result without a P2P IE.
 394                  */
 395                 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
 396                            " update for P2P interface", MAC2STR(res->bssid));
 397                 return;
 398         }
 399 #endif /* CONFIG_P2P */
 400         if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
 401             os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
 402                 return; /* Skip P2P listen discovery results here */
 403
 404         /* TODO: add option for ignoring BSSes we are not interested in
 405          * (to save memory) */
 406         bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
 407         if (bss == NULL)
 408                 wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
 409         else
 410                 wpa_bss_update(wpa_s, bss, res);
 411 }
 412
 413
 414 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
 415                                     const struct scan_info *info)
 416 {
 417         int found;
 418         size_t i;
 419
 420         if (info == NULL)
 421                 return 1;
 422
 423         if (info->num_freqs) {
 424                 found = 0;
 425                 for (i = 0; i < info->num_freqs; i++) {
 426                         if (bss->freq == info->freqs[i]) {
 427                                 found = 1;
 428                                 break;
 429                         }
 430                 }
 431                 if (!found)
 432                         return 0;
 433         }
 434
 435         if (info->num_ssids) {
 436                 found = 0;
 437                 for (i = 0; i < info->num_ssids; i++) {
 438                         const struct wpa_driver_scan_ssid *s = &info->ssids[i];
 439                         if ((s->ssid == NULL || s->ssid_len == 0) ||
 440                             (s->ssid_len == bss->ssid_len &&
 441                              os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
 442                              0)) {
 443                                 found = 1;
 444                                 break;
 445                         }
 446                 }
 447                 if (!found)
 448                         return 0;
 449         }
 450
 451         return 1;
 452 }
 453
 454
 455 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
 456                         int new_scan)
 457 {
 458         struct wpa_bss *bss, *n;
 459
 460         if (!new_scan)
 461                 return; /* do not expire entries without new scan */
 462
 463         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 464                 if (wpa_bss_in_use(wpa_s, bss))
 465                         continue;
 466                 if (!wpa_bss_included_in_scan(bss, info))
 467                         continue; /* expire only BSSes that were scanned */
 468                 if (bss->last_update_idx < wpa_s->bss_update_idx)
 469                         bss->scan_miss_count++;
 470                 if (bss->scan_miss_count >=
 471                     wpa_s->conf->bss_expiration_scan_count) {
 472                         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
 473                                 "no match in scan", bss->id);
 474                         wpa_bss_remove(wpa_s, bss);
 475                 }
 476         }
 477 }
 478
 479
 480 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
 481 {
 482         struct wpa_bss *bss, *n;
 483         struct os_time t;
 484
 485         if (dl_list_empty(&wpa_s->bss))
 486                 return;
 487
 488         os_get_time(&t);
 489         t.sec -= age;
 490
 491         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 492                 if (wpa_bss_in_use(wpa_s, bss))
 493                         continue;
 494
 495                 if (os_time_before(&bss->last_update, &t)) {
 496                         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
 497                                 "age", bss->id);
 498                         wpa_bss_remove(wpa_s, bss);
 499                 } else
 500                         break;
 501         }
 502 }
 503
 504
 505 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
 506 {
 507         struct wpa_supplicant *wpa_s = eloop_ctx;
 508
 509         wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age);
 510         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 511                                wpa_bss_timeout, wpa_s, NULL);
 512 }
 513
 514
 515 int wpa_bss_init(struct wpa_supplicant *wpa_s)
 516 {
 517         dl_list_init(&wpa_s->bss);
 518         dl_list_init(&wpa_s->bss_id);
 519         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 520                                wpa_bss_timeout, wpa_s, NULL);
 521         return 0;
 522 }
 523
 524
 525 void wpa_bss_flush(struct wpa_supplicant *wpa_s)
 526 {
 527         struct wpa_bss *bss, *n;
 528
 529         if (wpa_s->bss.next == NULL)
 530                 return; /* BSS table not yet initialized */
 531
 532         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 533                 if (wpa_bss_in_use(wpa_s, bss))
 534                         continue;
 535                 wpa_bss_remove(wpa_s, bss);
 536         }
 537 }
 538
 539
 540 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
 541 {
 542         eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
 543         wpa_bss_flush(wpa_s);
 544 }
 545
 546
 547 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
 548                                    const u8 *bssid)
 549 {
 550         struct wpa_bss *bss;
 551         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
 552                 return NULL;
 553         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 554                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
 555                         return bss;
 556         }
 557         return NULL;
 558 }
 559
 560
 561 #ifdef CONFIG_P2P
 562 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
 563                                           const u8 *dev_addr)
 564 {
 565         struct wpa_bss *bss;
 566         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 567                 u8 addr[ETH_ALEN];
 568                 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
 569                                        addr) == 0 &&
 570                     os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
 571                         return bss;
 572         }
 573         return NULL;
 574 }
 575 #endif /* CONFIG_P2P */
 576
 577
 578 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
 579 {
 580         struct wpa_bss *bss;
 581         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 582                 if (bss->id == id)
 583                         return bss;
 584         }
 585         return NULL;
 586 }
 587
 588
 589 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
 590 {
 591         const u8 *end, *pos;
 592
 593         pos = (const u8 *) (bss + 1);
 594         end = pos + bss->ie_len;
 595
 596         while (pos + 1 < end) {
 597                 if (pos + 2 + pos[1] > end)
 598                         break;
 599                 if (pos[0] == ie)
 600                         return pos;
 601                 pos += 2 + pos[1];
 602         }
 603
 604         return NULL;
 605 }
 606
 607
 608 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
 609 {
 610         const u8 *end, *pos;
 611
 612         pos = (const u8 *) (bss + 1);
 613         end = pos + bss->ie_len;
 614
 615         while (pos + 1 < end) {
 616                 if (pos + 2 + pos[1] > end)
 617                         break;
 618                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 619                     vendor_type == WPA_GET_BE32(&pos[2]))
 620                         return pos;
 621                 pos += 2 + pos[1];
 622         }
 623
 624         return NULL;
 625 }
 626
 627
 628 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
 629                                             u32 vendor_type)
 630 {
 631         struct wpabuf *buf;
 632         const u8 *end, *pos;
 633
 634         buf = wpabuf_alloc(bss->ie_len);
 635         if (buf == NULL)
 636                 return NULL;
 637
 638         pos = (const u8 *) (bss + 1);
 639         end = pos + bss->ie_len;
 640
 641         while (pos + 1 < end) {
 642                 if (pos + 2 + pos[1] > end)
 643                         break;
 644                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 645                     vendor_type == WPA_GET_BE32(&pos[2]))
 646                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
 647                 pos += 2 + pos[1];
 648         }
 649
 650         if (wpabuf_len(buf) == 0) {
 651                 wpabuf_free(buf);
 652                 buf = NULL;
 653         }
 654
 655         return buf;
 656 }
 657
 658
 659 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
 660 {
 661         int rate = 0;
 662         const u8 *ie;
 663         int i;
 664
 665         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 666         for (i = 0; ie && i < ie[1]; i++) {
 667                 if ((ie[i + 2] & 0x7f) > rate)
 668                         rate = ie[i + 2] & 0x7f;
 669         }
 670
 671         ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 672         for (i = 0; ie && i < ie[1]; i++) {
 673                 if ((ie[i + 2] & 0x7f) > rate)
 674                         rate = ie[i + 2] & 0x7f;
 675         }
 676
 677         return rate;
 678 }
 679
 680
 681 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
 682 {
 683         const u8 *ie, *ie2;
 684         int i, j;
 685         unsigned int len;
 686         u8 *r;
 687
 688         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 689         ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 690
 691         len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
 692
 693         r = os_malloc(len);
 694         if (!r)
 695                 return -1;
 696
 697         for (i = 0; ie && i < ie[1]; i++)
 698                 r[i] = ie[i + 2] & 0x7f;
 699
 700         for (j = 0; ie2 && j < ie2[1]; j++)
 701                 r[i + j] = ie2[j + 2] & 0x7f;
 702
 703         *rates = r;
 704         return len;
 705 }