wpa_supplicant/scan.c

   1 /*
   2  * WPA Supplicant - Scanning
   3  * Copyright (c) 2003-2010, 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 "config.h"
  21 #include "wpa_supplicant_i.h"
  22 #include "driver_i.h"
  23 #include "mlme.h"
  24 #include "wps_supplicant.h"
  25 #include "notify.h"
  26 #include "bss.h"
  27 #include "scan.h"
  28
  29
  30 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  31 {
  32         struct wpa_ssid *ssid;
  33         union wpa_event_data data;
  34
  35         ssid = wpa_supplicant_get_ssid(wpa_s);
  36         if (ssid == NULL)
  37                 return;
  38
  39         if (wpa_s->current_ssid == NULL) {
  40                 wpa_s->current_ssid = ssid;
  41                 if (wpa_s->current_ssid != NULL)
  42                         wpas_notify_network_changed(wpa_s);
  43         }
  44         wpa_supplicant_initiate_eapol(wpa_s);
  45         wpa_printf(MSG_DEBUG, "Already associated with a configured network - "
  46                    "generating associated event");
  47         os_memset(&data, 0, sizeof(data));
  48         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  49 }
  50
  51
  52 #ifdef CONFIG_WPS
  53 static int wpas_wps_in_use(struct wpa_config *conf,
  54                            enum wps_request_type *req_type)
  55 {
  56         struct wpa_ssid *ssid;
  57         int wps = 0;
  58
  59         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
  60                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  61                         continue;
  62
  63                 wps = 1;
  64                 *req_type = wpas_wps_get_req_type(ssid);
  65                 if (!ssid->eap.phase1)
  66                         continue;
  67
  68                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  69                         return 2;
  70         }
  71
  72         return wps;
  73 }
  74 #endif /* CONFIG_WPS */
  75
  76
  77 int wpa_supplicant_enabled_networks(struct wpa_config *conf)
  78 {
  79         struct wpa_ssid *ssid = conf->ssid;
  80         while (ssid) {
  81                 if (!ssid->disabled)
  82                         return 1;
  83                 ssid = ssid->next;
  84         }
  85         return 0;
  86 }
  87
  88
  89 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
  90                                      struct wpa_ssid *ssid)
  91 {
  92         while (ssid) {
  93                 if (!ssid->disabled)
  94                         break;
  95                 ssid = ssid->next;
  96         }
  97
  98         /* ap_scan=2 mode - try to associate with each SSID. */
  99         if (ssid == NULL) {
 100                 wpa_printf(MSG_DEBUG, "wpa_supplicant_scan: Reached "
 101                            "end of scan list - go back to beginning");
 102                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 103                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 104                 return;
 105         }
 106         if (ssid->next) {
 107                 /* Continue from the next SSID on the next attempt. */
 108                 wpa_s->prev_scan_ssid = ssid;
 109         } else {
 110                 /* Start from the beginning of the SSID list. */
 111                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 112         }
 113         wpa_supplicant_associate(wpa_s, NULL, ssid);
 114 }
 115
 116
 117 static int int_array_len(const int *a)
 118 {
 119         int i;
 120         for (i = 0; a && a[i]; i++)
 121                 ;
 122         return i;
 123 }
 124
 125
 126 static void int_array_concat(int **res, const int *a)
 127 {
 128         int reslen, alen, i;
 129         int *n;
 130
 131         reslen = int_array_len(*res);
 132         alen = int_array_len(a);
 133
 134         n = os_realloc(*res, (reslen + alen + 1) * sizeof(int));
 135         if (n == NULL) {
 136                 os_free(*res);
 137                 *res = NULL;
 138                 return;
 139         }
 140         for (i = 0; i <= alen; i++)
 141                 n[reslen + i] = a[i];
 142         *res = n;
 143 }
 144
 145
 146 static int freq_cmp(const void *a, const void *b)
 147 {
 148         int _a = *(int *) a;
 149         int _b = *(int *) b;
 150
 151         if (_a == 0)
 152                 return 1;
 153         if (_b == 0)
 154                 return -1;
 155         return _a - _b;
 156 }
 157
 158
 159 static void int_array_sort_unique(int *a)
 160 {
 161         int alen;
 162         int i, j;
 163
 164         if (a == NULL)
 165                 return;
 166
 167         alen = int_array_len(a);
 168         qsort(a, alen, sizeof(int), freq_cmp);
 169
 170         i = 0;
 171         j = 1;
 172         while (a[i] && a[j]) {
 173                 if (a[i] == a[j]) {
 174                         j++;
 175                         continue;
 176                 }
 177                 a[++i] = a[j++];
 178         }
 179         if (a[i])
 180                 i++;
 181         a[i] = 0;
 182 }
 183
 184
 185 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 186                                 struct wpa_driver_scan_params *params)
 187 {
 188         int ret;
 189
 190         wpa_supplicant_notify_scanning(wpa_s, 1);
 191
 192         if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)
 193                 ret = ieee80211_sta_req_scan(wpa_s, params);
 194         else
 195                 ret = wpa_drv_scan(wpa_s, params);
 196
 197         if (ret) {
 198                 wpa_supplicant_notify_scanning(wpa_s, 0);
 199                 wpas_notify_scan_done(wpa_s, 0);
 200         } else
 201                 wpa_s->scan_runs++;
 202
 203         return ret;
 204 }
 205
 206
 207 static struct wpa_driver_scan_filter *
 208 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 209 {
 210         struct wpa_driver_scan_filter *ssids;
 211         struct wpa_ssid *ssid;
 212         size_t count;
 213
 214         *num_ssids = 0;
 215         if (!conf->filter_ssids)
 216                 return NULL;
 217
 218         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 219                 if (ssid->ssid && ssid->ssid_len)
 220                         count++;
 221         }
 222         if (count == 0)
 223                 return NULL;
 224         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 225         if (ssids == NULL)
 226                 return NULL;
 227
 228         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 229                 if (!ssid->ssid || !ssid->ssid_len)
 230                         continue;
 231                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 232                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 233                 (*num_ssids)++;
 234         }
 235
 236         return ssids;
 237 }
 238
 239
 240 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 241 {
 242         struct wpa_supplicant *wpa_s = eloop_ctx;
 243         struct wpa_ssid *ssid;
 244         int scan_req = 0, ret;
 245         struct wpabuf *wps_ie = NULL;
 246         int wps = 0;
 247 #ifdef CONFIG_WPS
 248         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 249 #endif /* CONFIG_WPS */
 250         struct wpa_driver_scan_params params;
 251         size_t max_ssids;
 252         enum wpa_states prev_state;
 253
 254         if (wpa_s->disconnected && !wpa_s->scan_req) {
 255                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 256                 return;
 257         }
 258
 259         if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
 260             !wpa_s->scan_req) {
 261                 wpa_printf(MSG_DEBUG, "No enabled networks - do not scan");
 262                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 263                 return;
 264         }
 265
 266         if (wpa_s->conf->ap_scan != 0 &&
 267             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 268                 wpa_printf(MSG_DEBUG, "Using wired authentication - "
 269                            "overriding ap_scan configuration");
 270                 wpa_s->conf->ap_scan = 0;
 271                 wpas_notify_ap_scan_changed(wpa_s);
 272         }
 273
 274         if (wpa_s->conf->ap_scan == 0) {
 275                 wpa_supplicant_gen_assoc_event(wpa_s);
 276                 return;
 277         }
 278
 279         if ((wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) ||
 280             wpa_s->conf->ap_scan == 2)
 281                 max_ssids = 1;
 282         else {
 283                 max_ssids = wpa_s->max_scan_ssids;
 284                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 285                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 286         }
 287
 288 #ifdef CONFIG_WPS
 289         wps = wpas_wps_in_use(wpa_s->conf, &req_type);
 290 #endif /* CONFIG_WPS */
 291
 292         if (wpa_s->scan_res_tried == 0 && wpa_s->conf->ap_scan == 1 &&
 293             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) &&
 294             wps != 2 && !wpa_s->conf->filter_ssids) {
 295                 wpa_s->scan_res_tried++;
 296                 wpa_printf(MSG_DEBUG, "Trying to get current scan results "
 297                            "first without requesting a new scan to speed up "
 298                            "initial association");
 299                 wpa_supplicant_event(wpa_s, EVENT_SCAN_RESULTS, NULL);
 300                 return;
 301         }
 302
 303         scan_req = wpa_s->scan_req;
 304         wpa_s->scan_req = 0;
 305
 306         os_memset(&params, 0, sizeof(params));
 307
 308         prev_state = wpa_s->wpa_state;
 309         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 310             wpa_s->wpa_state == WPA_INACTIVE)
 311                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 312
 313         /* Find the starting point from which to continue scanning */
 314         ssid = wpa_s->conf->ssid;
 315         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 316                 while (ssid) {
 317                         if (ssid == wpa_s->prev_scan_ssid) {
 318                                 ssid = ssid->next;
 319                                 break;
 320                         }
 321                         ssid = ssid->next;
 322                 }
 323         }
 324
 325         if (scan_req != 2 && wpa_s->conf->ap_scan == 2) {
 326                 wpa_supplicant_assoc_try(wpa_s, ssid);
 327                 return;
 328         } else if (wpa_s->conf->ap_scan == 2) {
 329                 /*
 330                  * User-initiated scan request in ap_scan == 2; scan with
 331                  * wildcard SSID.
 332                  */
 333                 ssid = NULL;
 334         } else {
 335                 struct wpa_ssid *start = ssid, *tssid;
 336                 int freqs_set = 0;
 337                 if (ssid == NULL && max_ssids > 1)
 338                         ssid = wpa_s->conf->ssid;
 339                 while (ssid) {
 340                         if (!ssid->disabled && ssid->scan_ssid) {
 341                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 342                                                   ssid->ssid, ssid->ssid_len);
 343                                 params.ssids[params.num_ssids].ssid =
 344                                         ssid->ssid;
 345                                 params.ssids[params.num_ssids].ssid_len =
 346                                         ssid->ssid_len;
 347                                 params.num_ssids++;
 348                                 if (params.num_ssids + 1 >= max_ssids)
 349                                         break;
 350                         }
 351                         ssid = ssid->next;
 352                         if (ssid == start)
 353                                 break;
 354                         if (ssid == NULL && max_ssids > 1 &&
 355                             start != wpa_s->conf->ssid)
 356                                 ssid = wpa_s->conf->ssid;
 357                 }
 358
 359                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 360                         if (tssid->disabled)
 361                                 continue;
 362                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 363                                 int_array_concat(&params.freqs,
 364                                                  tssid->scan_freq);
 365                         } else {
 366                                 os_free(params.freqs);
 367                                 params.freqs = NULL;
 368                         }
 369                         freqs_set = 1;
 370                 }
 371                 int_array_sort_unique(params.freqs);
 372         }
 373
 374         if (ssid) {
 375                 wpa_s->prev_scan_ssid = ssid;
 376                 if (max_ssids > 1) {
 377                         wpa_printf(MSG_DEBUG, "Include wildcard SSID in the "
 378                                    "scan request");
 379                         params.num_ssids++;
 380                 }
 381                 wpa_printf(MSG_DEBUG, "Starting AP scan for specific SSID(s)");
 382         } else {
 383                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 384                 params.num_ssids++;
 385                 wpa_printf(MSG_DEBUG, "Starting AP scan for wildcard SSID");
 386         }
 387
 388 #ifdef CONFIG_WPS
 389         if (params.freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 390                 /*
 391                  * Optimize post-provisioning scan based on channel used
 392                  * during provisioning.
 393                  */
 394                 wpa_printf(MSG_DEBUG, "WPS: Scan only frequency %u MHz that "
 395                            "was used during provisioning", wpa_s->wps_freq);
 396                 params.freqs = os_zalloc(2 * sizeof(int));
 397                 if (params.freqs)
 398                         params.freqs[0] = wpa_s->wps_freq;
 399                 wpa_s->after_wps--;
 400         }
 401
 402         if (wps) {
 403                 wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev,
 404                                                 wpa_s->wps->uuid, req_type);
 405                 if (wps_ie) {
 406                         params.extra_ies = wpabuf_head(wps_ie);
 407                         params.extra_ies_len = wpabuf_len(wps_ie);
 408                 }
 409         }
 410 #endif /* CONFIG_WPS */
 411
 412         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 413                 wpa_s->conf, &params.num_filter_ssids);
 414
 415         ret = wpa_supplicant_trigger_scan(wpa_s, &params);
 416
 417         wpabuf_free(wps_ie);
 418         os_free(params.freqs);
 419         os_free(params.filter_ssids);
 420
 421         if (ret) {
 422                 wpa_printf(MSG_WARNING, "Failed to initiate AP scan.");
 423                 if (prev_state != wpa_s->wpa_state)
 424                         wpa_supplicant_set_state(wpa_s, prev_state);
 425                 wpa_supplicant_req_scan(wpa_s, 10, 0);
 426         } else
 427                 wpa_s->scan_runs++;
 428 }
 429
 430
 431 /**
 432  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 433  * @wpa_s: Pointer to wpa_supplicant data
 434  * @sec: Number of seconds after which to scan
 435  * @usec: Number of microseconds after which to scan
 436  *
 437  * This function is used to schedule a scan for neighboring access points after
 438  * the specified time.
 439  */
 440 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 441 {
 442         /* If there's at least one network that should be specifically scanned
 443          * then don't cancel the scan and reschedule.  Some drivers do
 444          * background scanning which generates frequent scan results, and that
 445          * causes the specific SSID scan to get continually pushed back and
 446          * never happen, which causes hidden APs to never get probe-scanned.
 447          */
 448         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 449             wpa_s->conf->ap_scan == 1) {
 450                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 451
 452                 while (ssid) {
 453                         if (!ssid->disabled && ssid->scan_ssid)
 454                                 break;
 455                         ssid = ssid->next;
 456                 }
 457                 if (ssid) {
 458                         wpa_msg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 459                                 "ensure that specific SSID scans occur");
 460                         return;
 461                 }
 462         }
 463
 464         wpa_msg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 465                 sec, usec);
 466         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 467         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 468 }
 469
 470
 471 /**
 472  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
 473  * @wpa_s: Pointer to wpa_supplicant data
 474  *
 475  * This function is used to cancel a scan request scheduled with
 476  * wpa_supplicant_req_scan().
 477  */
 478 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 479 {
 480         wpa_msg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 481         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 482 }
 483
 484
 485 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
 486                                     int scanning)
 487 {
 488         if (wpa_s->scanning != scanning) {
 489                 wpa_s->scanning = scanning;
 490                 wpas_notify_scanning(wpa_s);
 491         }
 492 }
 493
 494
 495 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
 496 {
 497         int rate = 0;
 498         const u8 *ie;
 499         int i;
 500
 501         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
 502         for (i = 0; ie && i < ie[1]; i++) {
 503                 if ((ie[i + 2] & 0x7f) > rate)
 504                         rate = ie[i + 2] & 0x7f;
 505         }
 506
 507         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
 508         for (i = 0; ie && i < ie[1]; i++) {
 509                 if ((ie[i + 2] & 0x7f) > rate)
 510                         rate = ie[i + 2] & 0x7f;
 511         }
 512
 513         return rate;
 514 }
 515
 516
 517 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
 518 {
 519         const u8 *end, *pos;
 520
 521         pos = (const u8 *) (res + 1);
 522         end = pos + res->ie_len;
 523
 524         while (pos + 1 < end) {
 525                 if (pos + 2 + pos[1] > end)
 526                         break;
 527                 if (pos[0] == ie)
 528                         return pos;
 529                 pos += 2 + pos[1];
 530         }
 531
 532         return NULL;
 533 }
 534
 535
 536 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
 537                                   u32 vendor_type)
 538 {
 539         const u8 *end, *pos;
 540
 541         pos = (const u8 *) (res + 1);
 542         end = pos + res->ie_len;
 543
 544         while (pos + 1 < end) {
 545                 if (pos + 2 + pos[1] > end)
 546                         break;
 547                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 548                     vendor_type == WPA_GET_BE32(&pos[2]))
 549                         return pos;
 550                 pos += 2 + pos[1];
 551         }
 552
 553         return NULL;
 554 }
 555
 556
 557 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
 558                                              u32 vendor_type)
 559 {
 560         struct wpabuf *buf;
 561         const u8 *end, *pos;
 562
 563         buf = wpabuf_alloc(res->ie_len);
 564         if (buf == NULL)
 565                 return NULL;
 566
 567         pos = (const u8 *) (res + 1);
 568         end = pos + res->ie_len;
 569
 570         while (pos + 1 < end) {
 571                 if (pos + 2 + pos[1] > end)
 572                         break;
 573                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 574                     vendor_type == WPA_GET_BE32(&pos[2]))
 575                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
 576                 pos += 2 + pos[1];
 577         }
 578
 579         if (wpabuf_len(buf) == 0) {
 580                 wpabuf_free(buf);
 581                 buf = NULL;
 582         }
 583
 584         return buf;
 585 }
 586
 587
 588 /* Compare function for sorting scan results. Return >0 if @b is considered
 589  * better. */
 590 static int wpa_scan_result_compar(const void *a, const void *b)
 591 {
 592         struct wpa_scan_res **_wa = (void *) a;
 593         struct wpa_scan_res **_wb = (void *) b;
 594         struct wpa_scan_res *wa = *_wa;
 595         struct wpa_scan_res *wb = *_wb;
 596         int wpa_a, wpa_b, maxrate_a, maxrate_b;
 597
 598         /* WPA/WPA2 support preferred */
 599         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
 600                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
 601         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
 602                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
 603
 604         if (wpa_b && !wpa_a)
 605                 return 1;
 606         if (!wpa_b && wpa_a)
 607                 return -1;
 608
 609         /* privacy support preferred */
 610         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
 611             (wb->caps & IEEE80211_CAP_PRIVACY))
 612                 return 1;
 613         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
 614             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
 615                 return -1;
 616
 617         /* best/max rate preferred if signal level close enough XXX */
 618         if ((wa->level && wb->level && abs(wb->level - wa->level) < 5) ||
 619             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
 620                 maxrate_a = wpa_scan_get_max_rate(wa);
 621                 maxrate_b = wpa_scan_get_max_rate(wb);
 622                 if (maxrate_a != maxrate_b)
 623                         return maxrate_b - maxrate_a;
 624         }
 625
 626         /* use freq for channel preference */
 627
 628         /* all things being equal, use signal level; if signal levels are
 629          * identical, use quality values since some drivers may only report
 630          * that value and leave the signal level zero */
 631         if (wb->level == wa->level)
 632                 return wb->qual - wa->qual;
 633         return wb->level - wa->level;
 634 }
 635
 636
 637 /**
 638  * wpa_supplicant_get_scan_results - Get scan results
 639  * @wpa_s: Pointer to wpa_supplicant data
 640  * @info: Information about what was scanned or %NULL if not available
 641  * @new_scan: Whether a new scan was performed
 642  * Returns: Scan results, %NULL on failure
 643  *
 644  * This function request the current scan results from the driver and updates
 645  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
 646  * results with wpa_scan_results_free().
 647  */
 648 struct wpa_scan_results *
 649 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
 650                                 struct scan_info *info, int new_scan)
 651 {
 652         struct wpa_scan_results *scan_res;
 653         size_t i;
 654
 655         if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)
 656                 scan_res = ieee80211_sta_get_scan_results(wpa_s);
 657         else
 658                 scan_res = wpa_drv_get_scan_results2(wpa_s);
 659         if (scan_res == NULL) {
 660                 wpa_printf(MSG_DEBUG, "Failed to get scan results");
 661                 return NULL;
 662         }
 663
 664         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
 665               wpa_scan_result_compar);
 666
 667         wpa_bss_update_start(wpa_s);
 668         for (i = 0; i < scan_res->num; i++)
 669                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
 670         wpa_bss_update_end(wpa_s, info, new_scan);
 671
 672         return scan_res;
 673 }
 674
 675
 676 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
 677 {
 678         struct wpa_scan_results *scan_res;
 679         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
 680         if (scan_res == NULL)
 681                 return -1;
 682         wpa_scan_results_free(scan_res);
 683
 684         return 0;
 685 }
 686
 687
 688 void wpa_scan_results_free(struct wpa_scan_results *res)
 689 {
 690         size_t i;
 691
 692         if (res == NULL)
 693                 return;
 694
 695         for (i = 0; i < res->num; i++)
 696                 os_free(res->res[i]);
 697         os_free(res->res);
 698         os_free(res);
 699 }