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_set_hessid(struct wpa_bss *bss)
  39 {
  40 #ifdef CONFIG_INTERWORKING
  41         const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING);
  42         if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) {
  43                 os_memset(bss->hessid, 0, ETH_ALEN);
  44                 return;
  45         }
  46         if (ie[1] == 7)
  47                 os_memcpy(bss->hessid, ie + 3, ETH_ALEN);
  48         else
  49                 os_memcpy(bss->hessid, ie + 5, ETH_ALEN);
  50 #endif /* CONFIG_INTERWORKING */
  51 }
  52
  53
  54 struct wpa_bss_anqp * wpa_bss_anqp_alloc(void)
  55 {
  56         struct wpa_bss_anqp *anqp;
  57         anqp = os_zalloc(sizeof(*anqp));
  58         if (anqp == NULL)
  59                 return NULL;
  60         anqp->users = 1;
  61         return anqp;
  62 }
  63
  64
  65 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp)
  66 {
  67         if (anqp == NULL)
  68                 return;
  69
  70         anqp->users--;
  71         if (anqp->users > 0) {
  72                 /* Another BSS entry holds a pointer to this ANQP info */
  73                 return;
  74         }
  75
  76 #ifdef CONFIG_INTERWORKING
  77         wpabuf_free(anqp->venue_name);
  78         wpabuf_free(anqp->network_auth_type);
  79         wpabuf_free(anqp->roaming_consortium);
  80         wpabuf_free(anqp->ip_addr_type_availability);
  81         wpabuf_free(anqp->nai_realm);
  82         wpabuf_free(anqp->anqp_3gpp);
  83         wpabuf_free(anqp->domain_name);
  84 #endif /* CONFIG_INTERWORKING */
  85 #ifdef CONFIG_HS20
  86         wpabuf_free(anqp->hs20_operator_friendly_name);
  87         wpabuf_free(anqp->hs20_wan_metrics);
  88         wpabuf_free(anqp->hs20_connection_capability);
  89         wpabuf_free(anqp->hs20_operating_class);
  90 #endif /* CONFIG_HS20 */
  91
  92         os_free(anqp);
  93 }
  94
  95
  96 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
  97                            const char *reason)
  98 {
  99         dl_list_del(&bss->list);
 100         dl_list_del(&bss->list_id);
 101         wpa_s->num_bss--;
 102         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
 103                 " SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
 104                 wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
 105         wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
 106         wpa_bss_anqp_free(bss->anqp);
 107         os_free(bss);
 108 }
 109
 110
 111 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
 112                              const u8 *ssid, size_t ssid_len)
 113 {
 114         struct wpa_bss *bss;
 115         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
 116                 return NULL;
 117         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 118                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
 119                     bss->ssid_len == ssid_len &&
 120                     os_memcmp(bss->ssid, ssid, ssid_len) == 0)
 121                         return bss;
 122         }
 123         return NULL;
 124 }
 125
 126
 127 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
 128 {
 129         os_time_t usec;
 130
 131         dst->flags = src->flags;
 132         os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
 133         dst->freq = src->freq;
 134         dst->beacon_int = src->beacon_int;
 135         dst->caps = src->caps;
 136         dst->qual = src->qual;
 137         dst->noise = src->noise;
 138         dst->level = src->level;
 139         dst->tsf = src->tsf;
 140
 141         os_get_time(&dst->last_update);
 142         dst->last_update.sec -= src->age / 1000;
 143         usec = (src->age % 1000) * 1000;
 144         if (dst->last_update.usec < usec) {
 145                 dst->last_update.sec--;
 146                 dst->last_update.usec += 1000000;
 147         }
 148         dst->last_update.usec -= usec;
 149 }
 150
 151
 152 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 153 {
 154         struct wpa_ssid *ssid;
 155
 156         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 157                 if (ssid->ssid == NULL || ssid->ssid_len == 0)
 158                         continue;
 159                 if (ssid->ssid_len == bss->ssid_len &&
 160                     os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
 161                         return 1;
 162         }
 163
 164         return 0;
 165 }
 166
 167
 168 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
 169 {
 170         return bss == wpa_s->current_bss ||
 171                 os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
 172                 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
 173 }
 174
 175
 176 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
 177 {
 178         struct wpa_bss *bss;
 179
 180         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 181                 if (!wpa_bss_known(wpa_s, bss)) {
 182                         wpa_bss_remove(wpa_s, bss, __func__);
 183                         return 0;
 184                 }
 185         }
 186
 187         return -1;
 188 }
 189
 190
 191 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
 192 {
 193         struct wpa_bss *bss;
 194
 195         /*
 196          * Remove the oldest entry that does not match with any configured
 197          * network.
 198          */
 199         if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
 200                 return 0;
 201
 202         /*
 203          * Remove the oldest entry that isn't currently in use.
 204          */
 205         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 206                 if (!wpa_bss_in_use(wpa_s, bss)) {
 207                         wpa_bss_remove(wpa_s, bss, __func__);
 208                         return 0;
 209                 }
 210         }
 211
 212         return -1;
 213 }
 214
 215
 216 static void wpa_bss_add(struct wpa_supplicant *wpa_s,
 217                         const u8 *ssid, size_t ssid_len,
 218                         struct wpa_scan_res *res)
 219 {
 220         struct wpa_bss *bss;
 221
 222         bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
 223         if (bss == NULL)
 224                 return;
 225         bss->id = wpa_s->bss_next_id++;
 226         bss->last_update_idx = wpa_s->bss_update_idx;
 227         wpa_bss_copy_res(bss, res);
 228         os_memcpy(bss->ssid, ssid, ssid_len);
 229         bss->ssid_len = ssid_len;
 230         bss->ie_len = res->ie_len;
 231         bss->beacon_ie_len = res->beacon_ie_len;
 232         os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 233         wpa_bss_set_hessid(bss);
 234
 235         dl_list_add_tail(&wpa_s->bss, &bss->list);
 236         dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
 237         wpa_s->num_bss++;
 238         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
 239                 " SSID '%s'",
 240                 bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
 241         wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
 242         if (wpa_s->num_bss > wpa_s->conf->bss_max_count &&
 243             wpa_bss_remove_oldest(wpa_s) != 0) {
 244                 wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d "
 245                            "because all BSSes are in use. We should normally "
 246                            "not get here!", (int) wpa_s->num_bss);
 247                 wpa_s->conf->bss_max_count = wpa_s->num_bss;
 248         }
 249 }
 250
 251
 252 static int are_ies_equal(const struct wpa_bss *old,
 253                          const struct wpa_scan_res *new, u32 ie)
 254 {
 255         const u8 *old_ie, *new_ie;
 256         struct wpabuf *old_ie_buff = NULL;
 257         struct wpabuf *new_ie_buff = NULL;
 258         int new_ie_len, old_ie_len, ret, is_multi;
 259
 260         switch (ie) {
 261         case WPA_IE_VENDOR_TYPE:
 262                 old_ie = wpa_bss_get_vendor_ie(old, ie);
 263                 new_ie = wpa_scan_get_vendor_ie(new, ie);
 264                 is_multi = 0;
 265                 break;
 266         case WPS_IE_VENDOR_TYPE:
 267                 old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
 268                 new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
 269                 is_multi = 1;
 270                 break;
 271         case WLAN_EID_RSN:
 272         case WLAN_EID_SUPP_RATES:
 273         case WLAN_EID_EXT_SUPP_RATES:
 274                 old_ie = wpa_bss_get_ie(old, ie);
 275                 new_ie = wpa_scan_get_ie(new, ie);
 276                 is_multi = 0;
 277                 break;
 278         default:
 279                 wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
 280                 return 0;
 281         }
 282
 283         if (is_multi) {
 284                 /* in case of multiple IEs stored in buffer */
 285                 old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
 286                 new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
 287                 old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
 288                 new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
 289         } else {
 290                 /* in case of single IE */
 291                 old_ie_len = old_ie ? old_ie[1] + 2 : 0;
 292                 new_ie_len = new_ie ? new_ie[1] + 2 : 0;
 293         }
 294
 295         if (!old_ie || !new_ie)
 296                 ret = !old_ie && !new_ie;
 297         else
 298                 ret = (old_ie_len == new_ie_len &&
 299                        os_memcmp(old_ie, new_ie, old_ie_len) == 0);
 300
 301         wpabuf_free(old_ie_buff);
 302         wpabuf_free(new_ie_buff);
 303
 304         return ret;
 305 }
 306
 307
 308 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
 309                                const struct wpa_scan_res *new)
 310 {
 311         u32 changes = 0;
 312         int caps_diff = old->caps ^ new->caps;
 313
 314         if (old->freq != new->freq)
 315                 changes |= WPA_BSS_FREQ_CHANGED_FLAG;
 316
 317         if (old->level != new->level)
 318                 changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
 319
 320         if (caps_diff & IEEE80211_CAP_PRIVACY)
 321                 changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
 322
 323         if (caps_diff & IEEE80211_CAP_IBSS)
 324                 changes |= WPA_BSS_MODE_CHANGED_FLAG;
 325
 326         if (old->ie_len == new->ie_len &&
 327             os_memcmp(old + 1, new + 1, old->ie_len) == 0)
 328                 return changes;
 329         changes |= WPA_BSS_IES_CHANGED_FLAG;
 330
 331         if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
 332                 changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
 333
 334         if (!are_ies_equal(old, new, WLAN_EID_RSN))
 335                 changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
 336
 337         if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
 338                 changes |= WPA_BSS_WPS_CHANGED_FLAG;
 339
 340         if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
 341             !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
 342                 changes |= WPA_BSS_RATES_CHANGED_FLAG;
 343
 344         return changes;
 345 }
 346
 347
 348 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
 349                                const struct wpa_bss *bss)
 350 {
 351         if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
 352                 wpas_notify_bss_freq_changed(wpa_s, bss->id);
 353
 354         if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
 355                 wpas_notify_bss_signal_changed(wpa_s, bss->id);
 356
 357         if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
 358                 wpas_notify_bss_privacy_changed(wpa_s, bss->id);
 359
 360         if (changes & WPA_BSS_MODE_CHANGED_FLAG)
 361                 wpas_notify_bss_mode_changed(wpa_s, bss->id);
 362
 363         if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
 364                 wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
 365
 366         if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
 367                 wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
 368
 369         if (changes & WPA_BSS_WPS_CHANGED_FLAG)
 370                 wpas_notify_bss_wps_changed(wpa_s, bss->id);
 371
 372         if (changes & WPA_BSS_IES_CHANGED_FLAG)
 373                 wpas_notify_bss_ies_changed(wpa_s, bss->id);
 374
 375         if (changes & WPA_BSS_RATES_CHANGED_FLAG)
 376                 wpas_notify_bss_rates_changed(wpa_s, bss->id);
 377 }
 378
 379
 380 static void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
 381                            struct wpa_scan_res *res)
 382 {
 383         u32 changes;
 384
 385         changes = wpa_bss_compare_res(bss, res);
 386         bss->scan_miss_count = 0;
 387         bss->last_update_idx = wpa_s->bss_update_idx;
 388         wpa_bss_copy_res(bss, res);
 389         /* Move the entry to the end of the list */
 390         dl_list_del(&bss->list);
 391         if (bss->ie_len + bss->beacon_ie_len >=
 392             res->ie_len + res->beacon_ie_len) {
 393                 os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
 394                 bss->ie_len = res->ie_len;
 395                 bss->beacon_ie_len = res->beacon_ie_len;
 396         } else {
 397                 struct wpa_bss *nbss;
 398                 struct dl_list *prev = bss->list_id.prev;
 399                 dl_list_del(&bss->list_id);
 400                 nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
 401                                   res->beacon_ie_len);
 402                 if (nbss) {
 403                         if (wpa_s->current_bss == bss)
 404                                 wpa_s->current_bss = nbss;
 405                         bss = nbss;
 406                         os_memcpy(bss + 1, res + 1,
 407                                   res->ie_len + res->beacon_ie_len);
 408                         bss->ie_len = res->ie_len;
 409                         bss->beacon_ie_len = res->beacon_ie_len;
 410                 }
 411                 dl_list_add(prev, &bss->list_id);
 412         }
 413         if (changes & WPA_BSS_IES_CHANGED_FLAG)
 414                 wpa_bss_set_hessid(bss);
 415         dl_list_add_tail(&wpa_s->bss, &bss->list);
 416
 417         notify_bss_changes(wpa_s, changes, bss);
 418 }
 419
 420
 421 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
 422 {
 423         wpa_s->bss_update_idx++;
 424         wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
 425                 wpa_s->bss_update_idx);
 426 }
 427
 428
 429 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
 430                              struct wpa_scan_res *res)
 431 {
 432         const u8 *ssid, *p2p;
 433         struct wpa_bss *bss;
 434
 435         ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
 436         if (ssid == NULL) {
 437                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
 438                         MACSTR, MAC2STR(res->bssid));
 439                 return;
 440         }
 441         if (ssid[1] > 32) {
 442                 wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
 443                         MACSTR, MAC2STR(res->bssid));
 444                 return;
 445         }
 446
 447         p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
 448 #ifdef CONFIG_P2P
 449         if (p2p == NULL &&
 450             wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
 451                 /*
 452                  * If it's a P2P specific interface, then don't update
 453                  * the scan result without a P2P IE.
 454                  */
 455                 wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
 456                            " update for P2P interface", MAC2STR(res->bssid));
 457                 return;
 458         }
 459 #endif /* CONFIG_P2P */
 460         if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
 461             os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
 462                 return; /* Skip P2P listen discovery results here */
 463
 464         /* TODO: add option for ignoring BSSes we are not interested in
 465          * (to save memory) */
 466         bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
 467         if (bss == NULL)
 468                 wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
 469         else
 470                 wpa_bss_update(wpa_s, bss, res);
 471 }
 472
 473
 474 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
 475                                     const struct scan_info *info)
 476 {
 477         int found;
 478         size_t i;
 479
 480         if (info == NULL)
 481                 return 1;
 482
 483         if (info->num_freqs) {
 484                 found = 0;
 485                 for (i = 0; i < info->num_freqs; i++) {
 486                         if (bss->freq == info->freqs[i]) {
 487                                 found = 1;
 488                                 break;
 489                         }
 490                 }
 491                 if (!found)
 492                         return 0;
 493         }
 494
 495         if (info->num_ssids) {
 496                 found = 0;
 497                 for (i = 0; i < info->num_ssids; i++) {
 498                         const struct wpa_driver_scan_ssid *s = &info->ssids[i];
 499                         if ((s->ssid == NULL || s->ssid_len == 0) ||
 500                             (s->ssid_len == bss->ssid_len &&
 501                              os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
 502                              0)) {
 503                                 found = 1;
 504                                 break;
 505                         }
 506                 }
 507                 if (!found)
 508                         return 0;
 509         }
 510
 511         return 1;
 512 }
 513
 514
 515 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
 516                         int new_scan)
 517 {
 518         struct wpa_bss *bss, *n;
 519
 520         if (!new_scan)
 521                 return; /* do not expire entries without new scan */
 522
 523         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 524                 if (wpa_bss_in_use(wpa_s, bss))
 525                         continue;
 526                 if (!wpa_bss_included_in_scan(bss, info))
 527                         continue; /* expire only BSSes that were scanned */
 528                 if (bss->last_update_idx < wpa_s->bss_update_idx)
 529                         bss->scan_miss_count++;
 530                 if (bss->scan_miss_count >=
 531                     wpa_s->conf->bss_expiration_scan_count) {
 532                         wpa_bss_remove(wpa_s, bss, "no match in scan");
 533                 }
 534         }
 535 }
 536
 537
 538 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
 539 {
 540         struct wpa_bss *bss, *n;
 541         struct os_time t;
 542
 543         if (dl_list_empty(&wpa_s->bss))
 544                 return;
 545
 546         os_get_time(&t);
 547         t.sec -= age;
 548
 549         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 550                 if (wpa_bss_in_use(wpa_s, bss))
 551                         continue;
 552
 553                 if (os_time_before(&bss->last_update, &t)) {
 554                         wpa_bss_remove(wpa_s, bss, __func__);
 555                 } else
 556                         break;
 557         }
 558 }
 559
 560
 561 static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
 562 {
 563         struct wpa_supplicant *wpa_s = eloop_ctx;
 564
 565         wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age);
 566         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 567                                wpa_bss_timeout, wpa_s, NULL);
 568 }
 569
 570
 571 int wpa_bss_init(struct wpa_supplicant *wpa_s)
 572 {
 573         dl_list_init(&wpa_s->bss);
 574         dl_list_init(&wpa_s->bss_id);
 575         eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
 576                                wpa_bss_timeout, wpa_s, NULL);
 577         return 0;
 578 }
 579
 580
 581 void wpa_bss_flush(struct wpa_supplicant *wpa_s)
 582 {
 583         struct wpa_bss *bss, *n;
 584
 585         if (wpa_s->bss.next == NULL)
 586                 return; /* BSS table not yet initialized */
 587
 588         dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
 589                 if (wpa_bss_in_use(wpa_s, bss))
 590                         continue;
 591                 wpa_bss_remove(wpa_s, bss, __func__);
 592         }
 593 }
 594
 595
 596 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
 597 {
 598         eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
 599         wpa_bss_flush(wpa_s);
 600 }
 601
 602
 603 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
 604                                    const u8 *bssid)
 605 {
 606         struct wpa_bss *bss;
 607         if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
 608                 return NULL;
 609         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 610                 if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
 611                         return bss;
 612         }
 613         return NULL;
 614 }
 615
 616
 617 #ifdef CONFIG_P2P
 618 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
 619                                           const u8 *dev_addr)
 620 {
 621         struct wpa_bss *bss;
 622         dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
 623                 u8 addr[ETH_ALEN];
 624                 if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
 625                                        addr) == 0 &&
 626                     os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
 627                         return bss;
 628         }
 629         return NULL;
 630 }
 631 #endif /* CONFIG_P2P */
 632
 633
 634 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
 635 {
 636         struct wpa_bss *bss;
 637         dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
 638                 if (bss->id == id)
 639                         return bss;
 640         }
 641         return NULL;
 642 }
 643
 644
 645 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
 646 {
 647         const u8 *end, *pos;
 648
 649         pos = (const u8 *) (bss + 1);
 650         end = pos + bss->ie_len;
 651
 652         while (pos + 1 < end) {
 653                 if (pos + 2 + pos[1] > end)
 654                         break;
 655                 if (pos[0] == ie)
 656                         return pos;
 657                 pos += 2 + pos[1];
 658         }
 659
 660         return NULL;
 661 }
 662
 663
 664 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
 665 {
 666         const u8 *end, *pos;
 667
 668         pos = (const u8 *) (bss + 1);
 669         end = pos + bss->ie_len;
 670
 671         while (pos + 1 < end) {
 672                 if (pos + 2 + pos[1] > end)
 673                         break;
 674                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 675                     vendor_type == WPA_GET_BE32(&pos[2]))
 676                         return pos;
 677                 pos += 2 + pos[1];
 678         }
 679
 680         return NULL;
 681 }
 682
 683
 684 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
 685                                             u32 vendor_type)
 686 {
 687         struct wpabuf *buf;
 688         const u8 *end, *pos;
 689
 690         buf = wpabuf_alloc(bss->ie_len);
 691         if (buf == NULL)
 692                 return NULL;
 693
 694         pos = (const u8 *) (bss + 1);
 695         end = pos + bss->ie_len;
 696
 697         while (pos + 1 < end) {
 698                 if (pos + 2 + pos[1] > end)
 699                         break;
 700                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 701                     vendor_type == WPA_GET_BE32(&pos[2]))
 702                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
 703                 pos += 2 + pos[1];
 704         }
 705
 706         if (wpabuf_len(buf) == 0) {
 707                 wpabuf_free(buf);
 708                 buf = NULL;
 709         }
 710
 711         return buf;
 712 }
 713
 714
 715 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
 716 {
 717         int rate = 0;
 718         const u8 *ie;
 719         int i;
 720
 721         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 722         for (i = 0; ie && i < ie[1]; i++) {
 723                 if ((ie[i + 2] & 0x7f) > rate)
 724                         rate = ie[i + 2] & 0x7f;
 725         }
 726
 727         ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 728         for (i = 0; ie && i < ie[1]; i++) {
 729                 if ((ie[i + 2] & 0x7f) > rate)
 730                         rate = ie[i + 2] & 0x7f;
 731         }
 732
 733         return rate;
 734 }
 735
 736
 737 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
 738 {
 739         const u8 *ie, *ie2;
 740         int i, j;
 741         unsigned int len;
 742         u8 *r;
 743
 744         ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
 745         ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
 746
 747         len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
 748
 749         r = os_malloc(len);
 750         if (!r)
 751                 return -1;
 752
 753         for (i = 0; ie && i < ie[1]; i++)
 754                 r[i] = ie[i + 2] & 0x7f;
 755
 756         for (j = 0; ie2 && j < ie2[1]; j++)
 757                 r[i + j] = ie2[j + 2] & 0x7f;
 758
 759         *rates = r;
 760         return len;
 761 }