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 "wps_supplicant.h"
  24 #include "p2p_supplicant.h"
  25 #include "p2p/p2p.h"
  26 #include "notify.h"
  27 #include "bss.h"
  28 #include "scan.h"
  29
  30
  31 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  32 {
  33         struct wpa_ssid *ssid;
  34         union wpa_event_data data;
  35
  36         ssid = wpa_supplicant_get_ssid(wpa_s);
  37         if (ssid == NULL)
  38                 return;
  39
  40         if (wpa_s->current_ssid == NULL) {
  41                 wpa_s->current_ssid = ssid;
  42                 if (wpa_s->current_ssid != NULL)
  43                         wpas_notify_network_changed(wpa_s);
  44         }
  45         wpa_supplicant_initiate_eapol(wpa_s);
  46         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
  47                 "network - generating associated event");
  48         os_memset(&data, 0, sizeof(data));
  49         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  50 }
  51
  52
  53 #ifdef CONFIG_WPS
  54 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
  55                            enum wps_request_type *req_type)
  56 {
  57         struct wpa_ssid *ssid;
  58         int wps = 0;
  59
  60         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
  61                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  62                         continue;
  63
  64                 wps = 1;
  65                 *req_type = wpas_wps_get_req_type(ssid);
  66                 if (!ssid->eap.phase1)
  67                         continue;
  68
  69                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  70                         return 2;
  71         }
  72
  73 #ifdef CONFIG_P2P
  74         wpa_s->wps->dev.p2p = 1;
  75         if (!wps) {
  76                 wps = 1;
  77                 *req_type = WPS_REQ_ENROLLEE_INFO;
  78         }
  79 #endif /* CONFIG_P2P */
  80
  81         return wps;
  82 }
  83 #endif /* CONFIG_WPS */
  84
  85
  86 int wpa_supplicant_enabled_networks(struct wpa_config *conf)
  87 {
  88         struct wpa_ssid *ssid = conf->ssid;
  89         int count = 0;
  90         while (ssid) {
  91                 if (!ssid->disabled)
  92                         count++;
  93                 ssid = ssid->next;
  94         }
  95         return count;
  96 }
  97
  98
  99 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
 100                                      struct wpa_ssid *ssid)
 101 {
 102         while (ssid) {
 103                 if (!ssid->disabled)
 104                         break;
 105                 ssid = ssid->next;
 106         }
 107
 108         /* ap_scan=2 mode - try to associate with each SSID. */
 109         if (ssid == NULL) {
 110                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 111                         "end of scan list - go back to beginning");
 112                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 113                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 114                 return;
 115         }
 116         if (ssid->next) {
 117                 /* Continue from the next SSID on the next attempt. */
 118                 wpa_s->prev_scan_ssid = ssid;
 119         } else {
 120                 /* Start from the beginning of the SSID list. */
 121                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 122         }
 123         wpa_supplicant_associate(wpa_s, NULL, ssid);
 124 }
 125
 126
 127 static int int_array_len(const int *a)
 128 {
 129         int i;
 130         for (i = 0; a && a[i]; i++)
 131                 ;
 132         return i;
 133 }
 134
 135
 136 static void int_array_concat(int **res, const int *a)
 137 {
 138         int reslen, alen, i;
 139         int *n;
 140
 141         reslen = int_array_len(*res);
 142         alen = int_array_len(a);
 143
 144         n = os_realloc(*res, (reslen + alen + 1) * sizeof(int));
 145         if (n == NULL) {
 146                 os_free(*res);
 147                 *res = NULL;
 148                 return;
 149         }
 150         for (i = 0; i <= alen; i++)
 151                 n[reslen + i] = a[i];
 152         *res = n;
 153 }
 154
 155
 156 static int freq_cmp(const void *a, const void *b)
 157 {
 158         int _a = *(int *) a;
 159         int _b = *(int *) b;
 160
 161         if (_a == 0)
 162                 return 1;
 163         if (_b == 0)
 164                 return -1;
 165         return _a - _b;
 166 }
 167
 168
 169 static void int_array_sort_unique(int *a)
 170 {
 171         int alen;
 172         int i, j;
 173
 174         if (a == NULL)
 175                 return;
 176
 177         alen = int_array_len(a);
 178         qsort(a, alen, sizeof(int), freq_cmp);
 179
 180         i = 0;
 181         j = 1;
 182         while (a[i] && a[j]) {
 183                 if (a[i] == a[j]) {
 184                         j++;
 185                         continue;
 186                 }
 187                 a[++i] = a[j++];
 188         }
 189         if (a[i])
 190                 i++;
 191         a[i] = 0;
 192 }
 193
 194
 195 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 196                                 struct wpa_driver_scan_params *params)
 197 {
 198         int ret;
 199
 200         wpa_supplicant_notify_scanning(wpa_s, 1);
 201
 202         ret = wpa_drv_scan(wpa_s, params);
 203         if (ret) {
 204                 wpa_supplicant_notify_scanning(wpa_s, 0);
 205                 wpas_notify_scan_done(wpa_s, 0);
 206         } else {
 207                 wpa_s->scan_runs++;
 208                 wpa_s->normal_scans++;
 209         }
 210
 211         return ret;
 212 }
 213
 214
 215 static void
 216 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 217 {
 218         struct wpa_supplicant *wpa_s = eloop_ctx;
 219
 220         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 221
 222         if (wpa_supplicant_req_sched_scan(wpa_s))
 223                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 224 }
 225
 226
 227 static void
 228 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 229 {
 230         struct wpa_supplicant *wpa_s = eloop_ctx;
 231
 232         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 233
 234         wpa_s->sched_scan_timed_out = 1;
 235         wpa_supplicant_cancel_sched_scan(wpa_s);
 236 }
 237
 238
 239 static int
 240 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 241                                 struct wpa_driver_scan_params *params,
 242                                 int interval)
 243 {
 244         int ret;
 245
 246         wpa_supplicant_notify_scanning(wpa_s, 1);
 247         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 248         if (ret)
 249                 wpa_supplicant_notify_scanning(wpa_s, 0);
 250         else
 251                 wpa_s->sched_scanning = 1;
 252
 253         return ret;
 254 }
 255
 256
 257 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 258 {
 259         int ret;
 260
 261         ret = wpa_drv_stop_sched_scan(wpa_s);
 262         if (ret) {
 263                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 264                 /* TODO: what to do if stopping fails? */
 265                 return -1;
 266         }
 267
 268         return ret;
 269 }
 270
 271
 272 static struct wpa_driver_scan_filter *
 273 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 274 {
 275         struct wpa_driver_scan_filter *ssids;
 276         struct wpa_ssid *ssid;
 277         size_t count;
 278
 279         *num_ssids = 0;
 280         if (!conf->filter_ssids)
 281                 return NULL;
 282
 283         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 284                 if (ssid->ssid && ssid->ssid_len)
 285                         count++;
 286         }
 287         if (count == 0)
 288                 return NULL;
 289         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 290         if (ssids == NULL)
 291                 return NULL;
 292
 293         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 294                 if (!ssid->ssid || !ssid->ssid_len)
 295                         continue;
 296                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 297                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 298                 (*num_ssids)++;
 299         }
 300
 301         return ssids;
 302 }
 303
 304
 305 static void wpa_supplicant_optimize_freqs(
 306         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 307 {
 308 #ifdef CONFIG_P2P
 309         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 310             wpa_s->go_params) {
 311                 /* Optimize provisioning state scan based on GO information */
 312                 if (wpa_s->p2p_in_provisioning < 5 &&
 313                     wpa_s->go_params->freq > 0) {
 314                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 315                                 "preferred frequency %d MHz",
 316                                 wpa_s->go_params->freq);
 317                         params->freqs = os_zalloc(2 * sizeof(int));
 318                         if (params->freqs)
 319                                 params->freqs[0] = wpa_s->go_params->freq;
 320                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 321                            wpa_s->go_params->freq_list[0]) {
 322                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 323                                 "channels");
 324                         int_array_concat(&params->freqs,
 325                                          wpa_s->go_params->freq_list);
 326                         if (params->freqs)
 327                                 int_array_sort_unique(params->freqs);
 328                 }
 329                 wpa_s->p2p_in_provisioning++;
 330         }
 331 #endif /* CONFIG_P2P */
 332
 333 #ifdef CONFIG_WPS
 334         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 335                 /*
 336                  * Optimize post-provisioning scan based on channel used
 337                  * during provisioning.
 338                  */
 339                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 340                         "that was used during provisioning", wpa_s->wps_freq);
 341                 params->freqs = os_zalloc(2 * sizeof(int));
 342                 if (params->freqs)
 343                         params->freqs[0] = wpa_s->wps_freq;
 344                 wpa_s->after_wps--;
 345         }
 346
 347         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 348         {
 349                 /* Optimize provisioning scan based on already known channel */
 350                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 351                         wpa_s->wps_freq);
 352                 params->freqs = os_zalloc(2 * sizeof(int));
 353                 if (params->freqs)
 354                         params->freqs[0] = wpa_s->wps_freq;
 355                 wpa_s->known_wps_freq = 0; /* only do this once */
 356         }
 357 #endif /* CONFIG_WPS */
 358 }
 359
 360
 361 #ifdef CONFIG_INTERWORKING
 362 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 363                                            struct wpabuf *buf)
 364 {
 365         if (wpa_s->conf->interworking == 0)
 366                 return;
 367
 368         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 369         wpabuf_put_u8(buf, 4);
 370         wpabuf_put_u8(buf, 0x00);
 371         wpabuf_put_u8(buf, 0x00);
 372         wpabuf_put_u8(buf, 0x00);
 373         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 374
 375         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 376         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 377                       1 + ETH_ALEN);
 378         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 379         /* No Venue Info */
 380         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 381                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 382 }
 383 #endif /* CONFIG_INTERWORKING */
 384
 385
 386 static struct wpabuf *
 387 wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s,
 388                          struct wpa_driver_scan_params *params)
 389 {
 390         struct wpabuf *extra_ie = NULL;
 391 #ifdef CONFIG_WPS
 392         int wps = 0;
 393         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 394 #endif /* CONFIG_WPS */
 395
 396 #ifdef CONFIG_INTERWORKING
 397         if (wpa_s->conf->interworking &&
 398             wpabuf_resize(&extra_ie, 100) == 0)
 399                 wpas_add_interworking_elements(wpa_s, extra_ie);
 400 #endif /* CONFIG_INTERWORKING */
 401
 402 #ifdef CONFIG_WPS
 403         wps = wpas_wps_in_use(wpa_s, &req_type);
 404
 405         if (wps) {
 406                 struct wpabuf *wps_ie;
 407                 wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev,
 408                                                 wpa_s->wps->uuid, req_type,
 409                                                 0, NULL);
 410                 if (wps_ie) {
 411                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 412                                 wpabuf_put_buf(extra_ie, wps_ie);
 413                         wpabuf_free(wps_ie);
 414                 }
 415         }
 416
 417 #ifdef CONFIG_P2P
 418         if (wps) {
 419                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 420                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 421                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 422         }
 423 #endif /* CONFIG_P2P */
 424
 425 #endif /* CONFIG_WPS */
 426
 427         return extra_ie;
 428 }
 429
 430
 431 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 432 {
 433         struct wpa_supplicant *wpa_s = eloop_ctx;
 434         struct wpa_ssid *ssid;
 435         int scan_req = 0, ret;
 436         struct wpabuf *extra_ie;
 437         struct wpa_driver_scan_params params;
 438         size_t max_ssids;
 439         enum wpa_states prev_state;
 440
 441         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 442                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 443                 return;
 444         }
 445
 446         if (wpa_s->disconnected && !wpa_s->scan_req) {
 447                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 448                 return;
 449         }
 450
 451         if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
 452             !wpa_s->scan_req) {
 453                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 454                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 455                 return;
 456         }
 457
 458         if (wpa_s->conf->ap_scan != 0 &&
 459             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 460                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 461                         "overriding ap_scan configuration");
 462                 wpa_s->conf->ap_scan = 0;
 463                 wpas_notify_ap_scan_changed(wpa_s);
 464         }
 465
 466         if (wpa_s->conf->ap_scan == 0) {
 467                 wpa_supplicant_gen_assoc_event(wpa_s);
 468                 return;
 469         }
 470
 471 #ifdef CONFIG_P2P
 472         if (wpas_p2p_in_progress(wpa_s)) {
 473                 if (wpa_s->wpa_state == WPA_SCANNING) {
 474                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 475                                 "while P2P operation is in progress");
 476                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 477                 } else {
 478                         wpa_dbg(wpa_s, MSG_DEBUG, "Do not request scan while "
 479                                 "P2P operation is in progress");
 480                 }
 481                 return;
 482         }
 483 #endif /* CONFIG_P2P */
 484
 485         if (wpa_s->conf->ap_scan == 2)
 486                 max_ssids = 1;
 487         else {
 488                 max_ssids = wpa_s->max_scan_ssids;
 489                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 490                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 491         }
 492
 493         scan_req = wpa_s->scan_req;
 494         wpa_s->scan_req = 0;
 495
 496         os_memset(&params, 0, sizeof(params));
 497
 498         prev_state = wpa_s->wpa_state;
 499         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 500             wpa_s->wpa_state == WPA_INACTIVE)
 501                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 502
 503         if (scan_req != 2 && wpa_s->connect_without_scan) {
 504                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 505                         if (ssid == wpa_s->connect_without_scan)
 506                                 break;
 507                 }
 508                 wpa_s->connect_without_scan = NULL;
 509                 if (ssid) {
 510                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 511                                    "without scan step");
 512                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 513                         return;
 514                 }
 515         }
 516
 517         /* Find the starting point from which to continue scanning */
 518         ssid = wpa_s->conf->ssid;
 519         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 520                 while (ssid) {
 521                         if (ssid == wpa_s->prev_scan_ssid) {
 522                                 ssid = ssid->next;
 523                                 break;
 524                         }
 525                         ssid = ssid->next;
 526                 }
 527         }
 528
 529         if (scan_req != 2 && wpa_s->conf->ap_scan == 2) {
 530                 wpa_s->connect_without_scan = NULL;
 531                 wpa_supplicant_assoc_try(wpa_s, ssid);
 532                 return;
 533         } else if (wpa_s->conf->ap_scan == 2) {
 534                 /*
 535                  * User-initiated scan request in ap_scan == 2; scan with
 536                  * wildcard SSID.
 537                  */
 538                 ssid = NULL;
 539         } else {
 540                 struct wpa_ssid *start = ssid, *tssid;
 541                 int freqs_set = 0;
 542                 if (ssid == NULL && max_ssids > 1)
 543                         ssid = wpa_s->conf->ssid;
 544                 while (ssid) {
 545                         if (!ssid->disabled && ssid->scan_ssid) {
 546                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 547                                                   ssid->ssid, ssid->ssid_len);
 548                                 params.ssids[params.num_ssids].ssid =
 549                                         ssid->ssid;
 550                                 params.ssids[params.num_ssids].ssid_len =
 551                                         ssid->ssid_len;
 552                                 params.num_ssids++;
 553                                 if (params.num_ssids + 1 >= max_ssids)
 554                                         break;
 555                         }
 556                         ssid = ssid->next;
 557                         if (ssid == start)
 558                                 break;
 559                         if (ssid == NULL && max_ssids > 1 &&
 560                             start != wpa_s->conf->ssid)
 561                                 ssid = wpa_s->conf->ssid;
 562                 }
 563
 564                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 565                         if (tssid->disabled)
 566                                 continue;
 567                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 568                                 int_array_concat(&params.freqs,
 569                                                  tssid->scan_freq);
 570                         } else {
 571                                 os_free(params.freqs);
 572                                 params.freqs = NULL;
 573                         }
 574                         freqs_set = 1;
 575                 }
 576                 int_array_sort_unique(params.freqs);
 577         }
 578
 579         if (ssid) {
 580                 wpa_s->prev_scan_ssid = ssid;
 581                 if (max_ssids > 1) {
 582                         wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 583                                 "the scan request");
 584                         params.num_ssids++;
 585                 }
 586                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for specific "
 587                         "SSID(s)");
 588         } else {
 589                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 590                 params.num_ssids++;
 591                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 592                         "SSID");
 593         }
 594
 595         wpa_supplicant_optimize_freqs(wpa_s, &params);
 596         extra_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 597
 598         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 599                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 600                         "generated frequency list");
 601                 params.freqs = wpa_s->next_scan_freqs;
 602         } else
 603                 os_free(wpa_s->next_scan_freqs);
 604         wpa_s->next_scan_freqs = NULL;
 605
 606         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 607                 wpa_s->conf, &params.num_filter_ssids);
 608         if (extra_ie) {
 609                 params.extra_ies = wpabuf_head(extra_ie);
 610                 params.extra_ies_len = wpabuf_len(extra_ie);
 611         }
 612
 613 #ifdef CONFIG_P2P
 614         if (wpa_s->p2p_in_provisioning) {
 615                 /*
 616                  * The interface may not yet be in P2P mode, so we have to
 617                  * explicitly request P2P probe to disable CCK rates.
 618                  */
 619                 params.p2p_probe = 1;
 620         }
 621 #endif /* CONFIG_P2P */
 622
 623         ret = wpa_supplicant_trigger_scan(wpa_s, &params);
 624
 625         wpabuf_free(extra_ie);
 626         os_free(params.freqs);
 627         os_free(params.filter_ssids);
 628
 629         if (ret) {
 630                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 631                 if (prev_state != wpa_s->wpa_state)
 632                         wpa_supplicant_set_state(wpa_s, prev_state);
 633                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 634         }
 635 }
 636
 637
 638 /**
 639  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 640  * @wpa_s: Pointer to wpa_supplicant data
 641  * @sec: Number of seconds after which to scan
 642  * @usec: Number of microseconds after which to scan
 643  *
 644  * This function is used to schedule a scan for neighboring access points after
 645  * the specified time.
 646  */
 647 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 648 {
 649         /* If there's at least one network that should be specifically scanned
 650          * then don't cancel the scan and reschedule.  Some drivers do
 651          * background scanning which generates frequent scan results, and that
 652          * causes the specific SSID scan to get continually pushed back and
 653          * never happen, which causes hidden APs to never get probe-scanned.
 654          */
 655         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 656             wpa_s->conf->ap_scan == 1) {
 657                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 658
 659                 while (ssid) {
 660                         if (!ssid->disabled && ssid->scan_ssid)
 661                                 break;
 662                         ssid = ssid->next;
 663                 }
 664                 if (ssid) {
 665                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 666                                 "ensure that specific SSID scans occur");
 667                         return;
 668                 }
 669         }
 670
 671         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 672                 sec, usec);
 673         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 674         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 675 }
 676
 677
 678 /**
 679  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 680  * @wpa_s: Pointer to wpa_supplicant data
 681  * @sec: Number of seconds after which to scan
 682  * @usec: Number of microseconds after which to scan
 683  *
 684  * This function is used to schedule periodic scans for neighboring
 685  * access points after the specified time.
 686  */
 687 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 688                                       int sec, int usec)
 689 {
 690         if (!wpa_s->sched_scan_supported)
 691                 return -1;
 692
 693         eloop_register_timeout(sec, usec,
 694                                wpa_supplicant_delayed_sched_scan_timeout,
 695                                wpa_s, NULL);
 696
 697         return 0;
 698 }
 699
 700
 701 /**
 702  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 703  * @wpa_s: Pointer to wpa_supplicant data
 704  *
 705  * This function is used to schedule periodic scans for neighboring
 706  * access points repeating the scan continuously.
 707  */
 708 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 709 {
 710         struct wpa_driver_scan_params params;
 711         enum wpa_states prev_state;
 712         struct wpa_ssid *ssid;
 713         struct wpabuf *wps_ie = NULL;
 714         int ret;
 715         unsigned int max_sched_scan_ssids;
 716         int wildcard = 0;
 717         int need_ssids;
 718
 719         if (!wpa_s->sched_scan_supported)
 720                 return -1;
 721
 722         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 723                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 724         else
 725                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 726         if (max_sched_scan_ssids < 1)
 727                 return -1;
 728
 729         if (wpa_s->sched_scanning) {
 730                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 731                 return 0;
 732         }
 733
 734         need_ssids = 0;
 735         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 736                 if (!ssid->disabled && !ssid->scan_ssid) {
 737                         /* Use wildcard SSID to find this network */
 738                         wildcard = 1;
 739                 } else if (!ssid->disabled && ssid->ssid_len)
 740                         need_ssids++;
 741         }
 742         if (wildcard)
 743                 need_ssids++;
 744
 745         if (wpa_s->normal_scans < 3 &&
 746             (need_ssids <= wpa_s->max_scan_ssids ||
 747              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
 748                 /*
 749                  * When normal scan can speed up operations, use that for the
 750                  * first operations before starting the sched_scan to allow
 751                  * user space sleep more. We do this only if the normal scan
 752                  * has functionality that is suitable for this or if the
 753                  * sched_scan does not have better support for multiple SSIDs.
 754                  */
 755                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 756                         "sched_scan for initial scans (normal_scans=%d)",
 757                         wpa_s->normal_scans);
 758                 return -1;
 759         }
 760
 761         os_memset(&params, 0, sizeof(params));
 762
 763         /* If we can't allocate space for the filters, we just don't filter */
 764         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
 765                                         sizeof(struct wpa_driver_scan_filter));
 766
 767         prev_state = wpa_s->wpa_state;
 768         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 769             wpa_s->wpa_state == WPA_INACTIVE)
 770                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 771
 772         /* Find the starting point from which to continue scanning */
 773         ssid = wpa_s->conf->ssid;
 774         if (wpa_s->prev_sched_ssid) {
 775                 while (ssid) {
 776                         if (ssid == wpa_s->prev_sched_ssid) {
 777                                 ssid = ssid->next;
 778                                 break;
 779                         }
 780                         ssid = ssid->next;
 781                 }
 782         }
 783
 784         if (!ssid || !wpa_s->prev_sched_ssid) {
 785                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
 786
 787                 wpa_s->sched_scan_interval = 10;
 788                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
 789                 wpa_s->first_sched_scan = 1;
 790                 ssid = wpa_s->conf->ssid;
 791                 wpa_s->prev_sched_ssid = ssid;
 792         }
 793
 794         if (wildcard) {
 795                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
 796                 params.num_ssids++;
 797         }
 798
 799         while (ssid) {
 800                 if (ssid->disabled)
 801                         goto next;
 802
 803                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
 804                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
 805                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
 806                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 807                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
 808                                   ssid->ssid, ssid->ssid_len);
 809                         params.filter_ssids[params.num_filter_ssids].ssid_len =
 810                                 ssid->ssid_len;
 811                         params.num_filter_ssids++;
 812                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
 813                 {
 814                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
 815                                 "filter for sched_scan - drop filter");
 816                         os_free(params.filter_ssids);
 817                         params.filter_ssids = NULL;
 818                         params.num_filter_ssids = 0;
 819                 }
 820
 821                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
 822                         if (params.num_ssids == max_sched_scan_ssids)
 823                                 break; /* only room for broadcast SSID */
 824                         wpa_dbg(wpa_s, MSG_DEBUG,
 825                                 "add to active scan ssid: %s",
 826                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 827                         params.ssids[params.num_ssids].ssid =
 828                                 ssid->ssid;
 829                         params.ssids[params.num_ssids].ssid_len =
 830                                 ssid->ssid_len;
 831                         params.num_ssids++;
 832                         if (params.num_ssids >= max_sched_scan_ssids) {
 833                                 wpa_s->prev_sched_ssid = ssid;
 834                                 break;
 835                         }
 836                 }
 837
 838         next:
 839                 wpa_s->prev_sched_ssid = ssid;
 840                 ssid = ssid->next;
 841         }
 842
 843         if (params.num_filter_ssids == 0) {
 844                 os_free(params.filter_ssids);
 845                 params.filter_ssids = NULL;
 846         }
 847
 848         if (wpa_s->wps)
 849                 wps_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 850
 851         if (ssid || !wpa_s->first_sched_scan) {
 852                 wpa_dbg(wpa_s, MSG_DEBUG,
 853                         "Starting sched scan: interval %d (no timeout)",
 854                         wpa_s->sched_scan_interval);
 855         } else {
 856                 wpa_dbg(wpa_s, MSG_DEBUG,
 857                         "Starting sched scan: interval %d timeout %d",
 858                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
 859         }
 860
 861         ret = wpa_supplicant_start_sched_scan(wpa_s, &params,
 862                                               wpa_s->sched_scan_interval);
 863         wpabuf_free(wps_ie);
 864         os_free(params.filter_ssids);
 865         if (ret) {
 866                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
 867                 if (prev_state != wpa_s->wpa_state)
 868                         wpa_supplicant_set_state(wpa_s, prev_state);
 869                 return ret;
 870         }
 871
 872         /* If we have more SSIDs to scan, add a timeout so we scan them too */
 873         if (ssid || !wpa_s->first_sched_scan) {
 874                 wpa_s->sched_scan_timed_out = 0;
 875                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
 876                                        wpa_supplicant_sched_scan_timeout,
 877                                        wpa_s, NULL);
 878                 wpa_s->first_sched_scan = 0;
 879                 wpa_s->sched_scan_timeout /= 2;
 880                 wpa_s->sched_scan_interval *= 2;
 881         }
 882
 883         return 0;
 884 }
 885
 886
 887 /**
 888  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
 889  * @wpa_s: Pointer to wpa_supplicant data
 890  *
 891  * This function is used to cancel a scan request scheduled with
 892  * wpa_supplicant_req_scan().
 893  */
 894 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 895 {
 896         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 897         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 898 }
 899
 900
 901 /**
 902  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
 903  * @wpa_s: Pointer to wpa_supplicant data
 904  *
 905  * This function is used to stop a periodic scheduled scan.
 906  */
 907 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
 908 {
 909         if (!wpa_s->sched_scanning)
 910                 return;
 911
 912         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
 913         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
 914         wpa_supplicant_stop_sched_scan(wpa_s);
 915 }
 916
 917
 918 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
 919                                     int scanning)
 920 {
 921         if (wpa_s->scanning != scanning) {
 922                 wpa_s->scanning = scanning;
 923                 wpas_notify_scanning(wpa_s);
 924         }
 925 }
 926
 927
 928 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
 929 {
 930         int rate = 0;
 931         const u8 *ie;
 932         int i;
 933
 934         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
 935         for (i = 0; ie && i < ie[1]; i++) {
 936                 if ((ie[i + 2] & 0x7f) > rate)
 937                         rate = ie[i + 2] & 0x7f;
 938         }
 939
 940         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
 941         for (i = 0; ie && i < ie[1]; i++) {
 942                 if ((ie[i + 2] & 0x7f) > rate)
 943                         rate = ie[i + 2] & 0x7f;
 944         }
 945
 946         return rate;
 947 }
 948
 949
 950 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
 951 {
 952         const u8 *end, *pos;
 953
 954         pos = (const u8 *) (res + 1);
 955         end = pos + res->ie_len;
 956
 957         while (pos + 1 < end) {
 958                 if (pos + 2 + pos[1] > end)
 959                         break;
 960                 if (pos[0] == ie)
 961                         return pos;
 962                 pos += 2 + pos[1];
 963         }
 964
 965         return NULL;
 966 }
 967
 968
 969 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
 970                                   u32 vendor_type)
 971 {
 972         const u8 *end, *pos;
 973
 974         pos = (const u8 *) (res + 1);
 975         end = pos + res->ie_len;
 976
 977         while (pos + 1 < end) {
 978                 if (pos + 2 + pos[1] > end)
 979                         break;
 980                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 981                     vendor_type == WPA_GET_BE32(&pos[2]))
 982                         return pos;
 983                 pos += 2 + pos[1];
 984         }
 985
 986         return NULL;
 987 }
 988
 989
 990 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
 991                                              u32 vendor_type)
 992 {
 993         struct wpabuf *buf;
 994         const u8 *end, *pos;
 995
 996         buf = wpabuf_alloc(res->ie_len);
 997         if (buf == NULL)
 998                 return NULL;
 999
1000         pos = (const u8 *) (res + 1);
1001         end = pos + res->ie_len;
1002
1003         while (pos + 1 < end) {
1004                 if (pos + 2 + pos[1] > end)
1005                         break;
1006                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1007                     vendor_type == WPA_GET_BE32(&pos[2]))
1008                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1009                 pos += 2 + pos[1];
1010         }
1011
1012         if (wpabuf_len(buf) == 0) {
1013                 wpabuf_free(buf);
1014                 buf = NULL;
1015         }
1016
1017         return buf;
1018 }
1019
1020
1021 struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
1022         const struct wpa_scan_res *res, u32 vendor_type)
1023 {
1024         struct wpabuf *buf;
1025         const u8 *end, *pos;
1026
1027         if (res->beacon_ie_len == 0)
1028                 return NULL;
1029         buf = wpabuf_alloc(res->beacon_ie_len);
1030         if (buf == NULL)
1031                 return NULL;
1032
1033         pos = (const u8 *) (res + 1);
1034         pos += res->ie_len;
1035         end = pos + res->beacon_ie_len;
1036
1037         while (pos + 1 < end) {
1038                 if (pos + 2 + pos[1] > end)
1039                         break;
1040                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1041                     vendor_type == WPA_GET_BE32(&pos[2]))
1042                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1043                 pos += 2 + pos[1];
1044         }
1045
1046         if (wpabuf_len(buf) == 0) {
1047                 wpabuf_free(buf);
1048                 buf = NULL;
1049         }
1050
1051         return buf;
1052 }
1053
1054
1055 /*
1056  * Channels with a great SNR can operate at full rate. What is a great SNR?
1057  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1058  * rule of thumb is that any SNR above 20 is good." This one
1059  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1060  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1061  * conservative value.
1062  */
1063 #define GREAT_SNR 30
1064
1065 /* Compare function for sorting scan results. Return >0 if @b is considered
1066  * better. */
1067 static int wpa_scan_result_compar(const void *a, const void *b)
1068 {
1069 #define IS_5GHZ(n) (n > 4000)
1070 #define MIN(a,b) a < b ? a : b
1071         struct wpa_scan_res **_wa = (void *) a;
1072         struct wpa_scan_res **_wb = (void *) b;
1073         struct wpa_scan_res *wa = *_wa;
1074         struct wpa_scan_res *wb = *_wb;
1075         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1076         int snr_a, snr_b;
1077
1078         /* WPA/WPA2 support preferred */
1079         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1080                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1081         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1082                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1083
1084         if (wpa_b && !wpa_a)
1085                 return 1;
1086         if (!wpa_b && wpa_a)
1087                 return -1;
1088
1089         /* privacy support preferred */
1090         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1091             (wb->caps & IEEE80211_CAP_PRIVACY))
1092                 return 1;
1093         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1094             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1095                 return -1;
1096
1097         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1098             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1099                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1100                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1101         } else {
1102                 /* Not suitable information to calculate SNR, so use level */
1103                 snr_a = wa->level;
1104                 snr_b = wb->level;
1105         }
1106
1107         /* best/max rate preferred if SNR close enough */
1108         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1109             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1110                 maxrate_a = wpa_scan_get_max_rate(wa);
1111                 maxrate_b = wpa_scan_get_max_rate(wb);
1112                 if (maxrate_a != maxrate_b)
1113                         return maxrate_b - maxrate_a;
1114                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1115                         return IS_5GHZ(wa->freq) ? -1 : 1;
1116         }
1117
1118         /* use freq for channel preference */
1119
1120         /* all things being equal, use SNR; if SNRs are
1121          * identical, use quality values since some drivers may only report
1122          * that value and leave the signal level zero */
1123         if (snr_b == snr_a)
1124                 return wb->qual - wa->qual;
1125         return snr_b - snr_a;
1126 #undef MIN
1127 #undef IS_5GHZ
1128 }
1129
1130
1131 #ifdef CONFIG_WPS
1132 /* Compare function for sorting scan results when searching a WPS AP for
1133  * provisioning. Return >0 if @b is considered better. */
1134 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1135 {
1136         struct wpa_scan_res **_wa = (void *) a;
1137         struct wpa_scan_res **_wb = (void *) b;
1138         struct wpa_scan_res *wa = *_wa;
1139         struct wpa_scan_res *wb = *_wb;
1140         int uses_wps_a, uses_wps_b;
1141         struct wpabuf *wps_a, *wps_b;
1142         int res;
1143
1144         /* Optimization - check WPS IE existence before allocated memory and
1145          * doing full reassembly. */
1146         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1147         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1148         if (uses_wps_a && !uses_wps_b)
1149                 return -1;
1150         if (!uses_wps_a && uses_wps_b)
1151                 return 1;
1152
1153         if (uses_wps_a && uses_wps_b) {
1154                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1155                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1156                 res = wps_ap_priority_compar(wps_a, wps_b);
1157                 wpabuf_free(wps_a);
1158                 wpabuf_free(wps_b);
1159                 if (res)
1160                         return res;
1161         }
1162
1163         /*
1164          * Do not use current AP security policy as a sorting criteria during
1165          * WPS provisioning step since the AP may get reconfigured at the
1166          * completion of provisioning.
1167          */
1168
1169         /* all things being equal, use signal level; if signal levels are
1170          * identical, use quality values since some drivers may only report
1171          * that value and leave the signal level zero */
1172         if (wb->level == wa->level)
1173                 return wb->qual - wa->qual;
1174         return wb->level - wa->level;
1175 }
1176 #endif /* CONFIG_WPS */
1177
1178
1179 static void dump_scan_res(struct wpa_scan_results *scan_res)
1180 {
1181 #ifndef CONFIG_NO_STDOUT_DEBUG
1182         size_t i;
1183
1184         if (scan_res->res == NULL || scan_res->num == 0)
1185                 return;
1186
1187         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1188
1189         for (i = 0; i < scan_res->num; i++) {
1190                 struct wpa_scan_res *r = scan_res->res[i];
1191                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1192                     == WPA_SCAN_LEVEL_DBM) {
1193                         int snr = r->level - r->noise;
1194                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1195                                    "noise=%d level=%d snr=%d%s flags=0x%x",
1196                                    MAC2STR(r->bssid), r->freq, r->qual,
1197                                    r->noise, r->level, snr,
1198                                    snr >= GREAT_SNR ? "*" : "", r->flags);
1199                 } else {
1200                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1201                                    "noise=%d level=%d flags=0x%x",
1202                                    MAC2STR(r->bssid), r->freq, r->qual,
1203                                    r->noise, r->level, r->flags);
1204                 }
1205         }
1206 #endif /* CONFIG_NO_STDOUT_DEBUG */
1207 }
1208
1209
1210 /**
1211  * wpa_supplicant_get_scan_results - Get scan results
1212  * @wpa_s: Pointer to wpa_supplicant data
1213  * @info: Information about what was scanned or %NULL if not available
1214  * @new_scan: Whether a new scan was performed
1215  * Returns: Scan results, %NULL on failure
1216  *
1217  * This function request the current scan results from the driver and updates
1218  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1219  * results with wpa_scan_results_free().
1220  */
1221 struct wpa_scan_results *
1222 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1223                                 struct scan_info *info, int new_scan)
1224 {
1225         struct wpa_scan_results *scan_res;
1226         size_t i;
1227         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1228
1229         scan_res = wpa_drv_get_scan_results2(wpa_s);
1230         if (scan_res == NULL) {
1231                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1232                 return NULL;
1233         }
1234
1235 #ifdef CONFIG_WPS
1236         if (wpas_wps_in_progress(wpa_s)) {
1237                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1238                         "provisioning rules");
1239                 compar = wpa_scan_result_wps_compar;
1240         }
1241 #endif /* CONFIG_WPS */
1242
1243         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1244               compar);
1245         dump_scan_res(scan_res);
1246
1247         wpa_bss_update_start(wpa_s);
1248         for (i = 0; i < scan_res->num; i++)
1249                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
1250         wpa_bss_update_end(wpa_s, info, new_scan);
1251
1252         return scan_res;
1253 }
1254
1255
1256 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1257 {
1258         struct wpa_scan_results *scan_res;
1259         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1260         if (scan_res == NULL)
1261                 return -1;
1262         wpa_scan_results_free(scan_res);
1263
1264         return 0;
1265 }