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         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p) {
  75                 wpa_s->wps->dev.p2p = 1;
  76                 if (!wps) {
  77                         wps = 1;
  78                         *req_type = WPS_REQ_ENROLLEE_INFO;
  79                 }
  80         }
  81 #endif /* CONFIG_P2P */
  82
  83         return wps;
  84 }
  85 #endif /* CONFIG_WPS */
  86
  87
  88 int wpa_supplicant_enabled_networks(struct wpa_config *conf)
  89 {
  90         struct wpa_ssid *ssid = conf->ssid;
  91         int count = 0;
  92         while (ssid) {
  93                 if (!ssid->disabled)
  94                         count++;
  95                 ssid = ssid->next;
  96         }
  97         return count;
  98 }
  99
 100
 101 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
 102                                      struct wpa_ssid *ssid)
 103 {
 104         while (ssid) {
 105                 if (!ssid->disabled)
 106                         break;
 107                 ssid = ssid->next;
 108         }
 109
 110         /* ap_scan=2 mode - try to associate with each SSID. */
 111         if (ssid == NULL) {
 112                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 113                         "end of scan list - go back to beginning");
 114                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 115                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 116                 return;
 117         }
 118         if (ssid->next) {
 119                 /* Continue from the next SSID on the next attempt. */
 120                 wpa_s->prev_scan_ssid = ssid;
 121         } else {
 122                 /* Start from the beginning of the SSID list. */
 123                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 124         }
 125         wpa_supplicant_associate(wpa_s, NULL, ssid);
 126 }
 127
 128
 129 static int int_array_len(const int *a)
 130 {
 131         int i;
 132         for (i = 0; a && a[i]; i++)
 133                 ;
 134         return i;
 135 }
 136
 137
 138 static void int_array_concat(int **res, const int *a)
 139 {
 140         int reslen, alen, i;
 141         int *n;
 142
 143         reslen = int_array_len(*res);
 144         alen = int_array_len(a);
 145
 146         n = os_realloc(*res, (reslen + alen + 1) * sizeof(int));
 147         if (n == NULL) {
 148                 os_free(*res);
 149                 *res = NULL;
 150                 return;
 151         }
 152         for (i = 0; i <= alen; i++)
 153                 n[reslen + i] = a[i];
 154         *res = n;
 155 }
 156
 157
 158 static int freq_cmp(const void *a, const void *b)
 159 {
 160         int _a = *(int *) a;
 161         int _b = *(int *) b;
 162
 163         if (_a == 0)
 164                 return 1;
 165         if (_b == 0)
 166                 return -1;
 167         return _a - _b;
 168 }
 169
 170
 171 static void int_array_sort_unique(int *a)
 172 {
 173         int alen;
 174         int i, j;
 175
 176         if (a == NULL)
 177                 return;
 178
 179         alen = int_array_len(a);
 180         qsort(a, alen, sizeof(int), freq_cmp);
 181
 182         i = 0;
 183         j = 1;
 184         while (a[i] && a[j]) {
 185                 if (a[i] == a[j]) {
 186                         j++;
 187                         continue;
 188                 }
 189                 a[++i] = a[j++];
 190         }
 191         if (a[i])
 192                 i++;
 193         a[i] = 0;
 194 }
 195
 196
 197 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 198                                 struct wpa_driver_scan_params *params)
 199 {
 200         int ret;
 201
 202         wpa_supplicant_notify_scanning(wpa_s, 1);
 203
 204         ret = wpa_drv_scan(wpa_s, params);
 205         if (ret) {
 206                 wpa_supplicant_notify_scanning(wpa_s, 0);
 207                 wpas_notify_scan_done(wpa_s, 0);
 208         } else {
 209                 wpa_s->scan_runs++;
 210                 wpa_s->normal_scans++;
 211         }
 212
 213         return ret;
 214 }
 215
 216
 217 static void
 218 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 219 {
 220         struct wpa_supplicant *wpa_s = eloop_ctx;
 221
 222         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 223
 224         if (wpa_supplicant_req_sched_scan(wpa_s))
 225                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 226 }
 227
 228
 229 static void
 230 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 231 {
 232         struct wpa_supplicant *wpa_s = eloop_ctx;
 233
 234         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 235
 236         wpa_s->sched_scan_timed_out = 1;
 237         wpa_supplicant_cancel_sched_scan(wpa_s);
 238 }
 239
 240
 241 static int
 242 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 243                                 struct wpa_driver_scan_params *params,
 244                                 int interval)
 245 {
 246         int ret;
 247
 248         wpa_supplicant_notify_scanning(wpa_s, 1);
 249         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 250         if (ret)
 251                 wpa_supplicant_notify_scanning(wpa_s, 0);
 252         else
 253                 wpa_s->sched_scanning = 1;
 254
 255         return ret;
 256 }
 257
 258
 259 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 260 {
 261         int ret;
 262
 263         ret = wpa_drv_stop_sched_scan(wpa_s);
 264         if (ret) {
 265                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 266                 /* TODO: what to do if stopping fails? */
 267                 return -1;
 268         }
 269
 270         return ret;
 271 }
 272
 273
 274 static struct wpa_driver_scan_filter *
 275 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 276 {
 277         struct wpa_driver_scan_filter *ssids;
 278         struct wpa_ssid *ssid;
 279         size_t count;
 280
 281         *num_ssids = 0;
 282         if (!conf->filter_ssids)
 283                 return NULL;
 284
 285         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 286                 if (ssid->ssid && ssid->ssid_len)
 287                         count++;
 288         }
 289         if (count == 0)
 290                 return NULL;
 291         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 292         if (ssids == NULL)
 293                 return NULL;
 294
 295         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 296                 if (!ssid->ssid || !ssid->ssid_len)
 297                         continue;
 298                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 299                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 300                 (*num_ssids)++;
 301         }
 302
 303         return ssids;
 304 }
 305
 306
 307 static void wpa_supplicant_optimize_freqs(
 308         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 309 {
 310 #ifdef CONFIG_P2P
 311         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 312             wpa_s->go_params) {
 313                 /* Optimize provisioning state scan based on GO information */
 314                 if (wpa_s->p2p_in_provisioning < 5 &&
 315                     wpa_s->go_params->freq > 0) {
 316                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 317                                 "preferred frequency %d MHz",
 318                                 wpa_s->go_params->freq);
 319                         params->freqs = os_zalloc(2 * sizeof(int));
 320                         if (params->freqs)
 321                                 params->freqs[0] = wpa_s->go_params->freq;
 322                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 323                            wpa_s->go_params->freq_list[0]) {
 324                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 325                                 "channels");
 326                         int_array_concat(&params->freqs,
 327                                          wpa_s->go_params->freq_list);
 328                         if (params->freqs)
 329                                 int_array_sort_unique(params->freqs);
 330                 }
 331                 wpa_s->p2p_in_provisioning++;
 332         }
 333 #endif /* CONFIG_P2P */
 334
 335 #ifdef CONFIG_WPS
 336         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 337                 /*
 338                  * Optimize post-provisioning scan based on channel used
 339                  * during provisioning.
 340                  */
 341                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 342                         "that was used during provisioning", wpa_s->wps_freq);
 343                 params->freqs = os_zalloc(2 * sizeof(int));
 344                 if (params->freqs)
 345                         params->freqs[0] = wpa_s->wps_freq;
 346                 wpa_s->after_wps--;
 347         }
 348
 349         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 350         {
 351                 /* Optimize provisioning scan based on already known channel */
 352                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 353                         wpa_s->wps_freq);
 354                 params->freqs = os_zalloc(2 * sizeof(int));
 355                 if (params->freqs)
 356                         params->freqs[0] = wpa_s->wps_freq;
 357                 wpa_s->known_wps_freq = 0; /* only do this once */
 358         }
 359 #endif /* CONFIG_WPS */
 360 }
 361
 362
 363 #ifdef CONFIG_INTERWORKING
 364 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 365                                            struct wpabuf *buf)
 366 {
 367         if (wpa_s->conf->interworking == 0)
 368                 return;
 369
 370         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 371         wpabuf_put_u8(buf, 4);
 372         wpabuf_put_u8(buf, 0x00);
 373         wpabuf_put_u8(buf, 0x00);
 374         wpabuf_put_u8(buf, 0x00);
 375         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 376
 377         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 378         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 379                       1 + ETH_ALEN);
 380         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 381         /* No Venue Info */
 382         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 383                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 384 }
 385 #endif /* CONFIG_INTERWORKING */
 386
 387
 388 static struct wpabuf *
 389 wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s,
 390                          struct wpa_driver_scan_params *params)
 391 {
 392         struct wpabuf *extra_ie = NULL;
 393 #ifdef CONFIG_WPS
 394         int wps = 0;
 395         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 396 #endif /* CONFIG_WPS */
 397
 398 #ifdef CONFIG_INTERWORKING
 399         if (wpa_s->conf->interworking &&
 400             wpabuf_resize(&extra_ie, 100) == 0)
 401                 wpas_add_interworking_elements(wpa_s, extra_ie);
 402 #endif /* CONFIG_INTERWORKING */
 403
 404 #ifdef CONFIG_WPS
 405         wps = wpas_wps_in_use(wpa_s, &req_type);
 406
 407         if (wps) {
 408                 struct wpabuf *wps_ie;
 409                 wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev,
 410                                                 wpa_s->wps->uuid, req_type,
 411                                                 0, NULL);
 412                 if (wps_ie) {
 413                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 414                                 wpabuf_put_buf(extra_ie, wps_ie);
 415                         wpabuf_free(wps_ie);
 416                 }
 417         }
 418
 419 #ifdef CONFIG_P2P
 420         if (wps) {
 421                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 422                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 423                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 424         }
 425 #endif /* CONFIG_P2P */
 426
 427 #endif /* CONFIG_WPS */
 428
 429         return extra_ie;
 430 }
 431
 432
 433 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 434 {
 435         struct wpa_supplicant *wpa_s = eloop_ctx;
 436         struct wpa_ssid *ssid;
 437         int scan_req = 0, ret;
 438         struct wpabuf *extra_ie;
 439         struct wpa_driver_scan_params params;
 440         size_t max_ssids;
 441         enum wpa_states prev_state;
 442
 443         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 444                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 445                 return;
 446         }
 447
 448         if (wpa_s->disconnected && !wpa_s->scan_req) {
 449                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 450                 return;
 451         }
 452
 453         if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
 454             !wpa_s->scan_req) {
 455                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 456                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 457                 return;
 458         }
 459
 460         if (wpa_s->conf->ap_scan != 0 &&
 461             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 462                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 463                         "overriding ap_scan configuration");
 464                 wpa_s->conf->ap_scan = 0;
 465                 wpas_notify_ap_scan_changed(wpa_s);
 466         }
 467
 468         if (wpa_s->conf->ap_scan == 0) {
 469                 wpa_supplicant_gen_assoc_event(wpa_s);
 470                 return;
 471         }
 472
 473 #ifdef CONFIG_P2P
 474         if (wpas_p2p_in_progress(wpa_s)) {
 475                 if (wpa_s->wpa_state == WPA_SCANNING) {
 476                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 477                                 "while P2P operation is in progress");
 478                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 479                 } else {
 480                         wpa_dbg(wpa_s, MSG_DEBUG, "Do not request scan while "
 481                                 "P2P operation is in progress");
 482                 }
 483                 return;
 484         }
 485 #endif /* CONFIG_P2P */
 486
 487         if (wpa_s->conf->ap_scan == 2)
 488                 max_ssids = 1;
 489         else {
 490                 max_ssids = wpa_s->max_scan_ssids;
 491                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 492                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 493         }
 494
 495         scan_req = wpa_s->scan_req;
 496         wpa_s->scan_req = 0;
 497
 498         os_memset(&params, 0, sizeof(params));
 499
 500         prev_state = wpa_s->wpa_state;
 501         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 502             wpa_s->wpa_state == WPA_INACTIVE)
 503                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 504
 505         if (scan_req != 2 && wpa_s->connect_without_scan) {
 506                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 507                         if (ssid == wpa_s->connect_without_scan)
 508                                 break;
 509                 }
 510                 wpa_s->connect_without_scan = NULL;
 511                 if (ssid) {
 512                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 513                                    "without scan step");
 514                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 515                         return;
 516                 }
 517         }
 518
 519         /* Find the starting point from which to continue scanning */
 520         ssid = wpa_s->conf->ssid;
 521         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 522                 while (ssid) {
 523                         if (ssid == wpa_s->prev_scan_ssid) {
 524                                 ssid = ssid->next;
 525                                 break;
 526                         }
 527                         ssid = ssid->next;
 528                 }
 529         }
 530
 531         if (scan_req != 2 && wpa_s->conf->ap_scan == 2) {
 532                 wpa_s->connect_without_scan = NULL;
 533                 wpa_supplicant_assoc_try(wpa_s, ssid);
 534                 return;
 535         } else if (wpa_s->conf->ap_scan == 2) {
 536                 /*
 537                  * User-initiated scan request in ap_scan == 2; scan with
 538                  * wildcard SSID.
 539                  */
 540                 ssid = NULL;
 541         } else {
 542                 struct wpa_ssid *start = ssid, *tssid;
 543                 int freqs_set = 0;
 544                 if (ssid == NULL && max_ssids > 1)
 545                         ssid = wpa_s->conf->ssid;
 546                 while (ssid) {
 547                         if (!ssid->disabled && ssid->scan_ssid) {
 548                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 549                                                   ssid->ssid, ssid->ssid_len);
 550                                 params.ssids[params.num_ssids].ssid =
 551                                         ssid->ssid;
 552                                 params.ssids[params.num_ssids].ssid_len =
 553                                         ssid->ssid_len;
 554                                 params.num_ssids++;
 555                                 if (params.num_ssids + 1 >= max_ssids)
 556                                         break;
 557                         }
 558                         ssid = ssid->next;
 559                         if (ssid == start)
 560                                 break;
 561                         if (ssid == NULL && max_ssids > 1 &&
 562                             start != wpa_s->conf->ssid)
 563                                 ssid = wpa_s->conf->ssid;
 564                 }
 565
 566                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 567                         if (tssid->disabled)
 568                                 continue;
 569                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 570                                 int_array_concat(&params.freqs,
 571                                                  tssid->scan_freq);
 572                         } else {
 573                                 os_free(params.freqs);
 574                                 params.freqs = NULL;
 575                         }
 576                         freqs_set = 1;
 577                 }
 578                 int_array_sort_unique(params.freqs);
 579         }
 580
 581         if (ssid) {
 582                 wpa_s->prev_scan_ssid = ssid;
 583                 if (max_ssids > 1) {
 584                         wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 585                                 "the scan request");
 586                         params.num_ssids++;
 587                 }
 588                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for specific "
 589                         "SSID(s)");
 590         } else {
 591                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 592                 params.num_ssids++;
 593                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 594                         "SSID");
 595         }
 596
 597         wpa_supplicant_optimize_freqs(wpa_s, &params);
 598         extra_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 599
 600         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 601                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 602                         "generated frequency list");
 603                 params.freqs = wpa_s->next_scan_freqs;
 604         } else
 605                 os_free(wpa_s->next_scan_freqs);
 606         wpa_s->next_scan_freqs = NULL;
 607
 608         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 609                 wpa_s->conf, &params.num_filter_ssids);
 610         if (extra_ie) {
 611                 params.extra_ies = wpabuf_head(extra_ie);
 612                 params.extra_ies_len = wpabuf_len(extra_ie);
 613         }
 614
 615 #ifdef CONFIG_P2P
 616         if (wpa_s->p2p_in_provisioning) {
 617                 /*
 618                  * The interface may not yet be in P2P mode, so we have to
 619                  * explicitly request P2P probe to disable CCK rates.
 620                  */
 621                 params.p2p_probe = 1;
 622         }
 623 #endif /* CONFIG_P2P */
 624
 625         ret = wpa_supplicant_trigger_scan(wpa_s, &params);
 626
 627         wpabuf_free(extra_ie);
 628         os_free(params.freqs);
 629         os_free(params.filter_ssids);
 630
 631         if (ret) {
 632                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 633                 if (prev_state != wpa_s->wpa_state)
 634                         wpa_supplicant_set_state(wpa_s, prev_state);
 635                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 636         }
 637 }
 638
 639
 640 /**
 641  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 642  * @wpa_s: Pointer to wpa_supplicant data
 643  * @sec: Number of seconds after which to scan
 644  * @usec: Number of microseconds after which to scan
 645  *
 646  * This function is used to schedule a scan for neighboring access points after
 647  * the specified time.
 648  */
 649 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 650 {
 651         /* If there's at least one network that should be specifically scanned
 652          * then don't cancel the scan and reschedule.  Some drivers do
 653          * background scanning which generates frequent scan results, and that
 654          * causes the specific SSID scan to get continually pushed back and
 655          * never happen, which causes hidden APs to never get probe-scanned.
 656          */
 657         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 658             wpa_s->conf->ap_scan == 1) {
 659                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 660
 661                 while (ssid) {
 662                         if (!ssid->disabled && ssid->scan_ssid)
 663                                 break;
 664                         ssid = ssid->next;
 665                 }
 666                 if (ssid) {
 667                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 668                                 "ensure that specific SSID scans occur");
 669                         return;
 670                 }
 671         }
 672
 673         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 674                 sec, usec);
 675         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 676         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 677 }
 678
 679
 680 /**
 681  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 682  * @wpa_s: Pointer to wpa_supplicant data
 683  * @sec: Number of seconds after which to scan
 684  * @usec: Number of microseconds after which to scan
 685  *
 686  * This function is used to schedule periodic scans for neighboring
 687  * access points after the specified time.
 688  */
 689 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 690                                       int sec, int usec)
 691 {
 692         if (!wpa_s->sched_scan_supported)
 693                 return -1;
 694
 695         eloop_register_timeout(sec, usec,
 696                                wpa_supplicant_delayed_sched_scan_timeout,
 697                                wpa_s, NULL);
 698
 699         return 0;
 700 }
 701
 702
 703 /**
 704  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 705  * @wpa_s: Pointer to wpa_supplicant data
 706  *
 707  * This function is used to schedule periodic scans for neighboring
 708  * access points repeating the scan continuously.
 709  */
 710 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 711 {
 712         struct wpa_driver_scan_params params;
 713         enum wpa_states prev_state;
 714         struct wpa_ssid *ssid;
 715         struct wpabuf *wps_ie = NULL;
 716         int ret;
 717         unsigned int max_sched_scan_ssids;
 718         int wildcard = 0;
 719         int need_ssids;
 720
 721         if (!wpa_s->sched_scan_supported)
 722                 return -1;
 723
 724         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 725                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 726         else
 727                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 728         if (max_sched_scan_ssids < 1)
 729                 return -1;
 730
 731         if (wpa_s->sched_scanning) {
 732                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 733                 return 0;
 734         }
 735
 736         need_ssids = 0;
 737         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 738                 if (!ssid->disabled && !ssid->scan_ssid) {
 739                         /* Use wildcard SSID to find this network */
 740                         wildcard = 1;
 741                 } else if (!ssid->disabled && ssid->ssid_len)
 742                         need_ssids++;
 743         }
 744         if (wildcard)
 745                 need_ssids++;
 746
 747         if (wpa_s->normal_scans < 3 &&
 748             (need_ssids <= wpa_s->max_scan_ssids ||
 749              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
 750                 /*
 751                  * When normal scan can speed up operations, use that for the
 752                  * first operations before starting the sched_scan to allow
 753                  * user space sleep more. We do this only if the normal scan
 754                  * has functionality that is suitable for this or if the
 755                  * sched_scan does not have better support for multiple SSIDs.
 756                  */
 757                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 758                         "sched_scan for initial scans (normal_scans=%d)",
 759                         wpa_s->normal_scans);
 760                 return -1;
 761         }
 762
 763         os_memset(&params, 0, sizeof(params));
 764
 765         /* If we can't allocate space for the filters, we just don't filter */
 766         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
 767                                         sizeof(struct wpa_driver_scan_filter));
 768
 769         prev_state = wpa_s->wpa_state;
 770         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 771             wpa_s->wpa_state == WPA_INACTIVE)
 772                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 773
 774         /* Find the starting point from which to continue scanning */
 775         ssid = wpa_s->conf->ssid;
 776         if (wpa_s->prev_sched_ssid) {
 777                 while (ssid) {
 778                         if (ssid == wpa_s->prev_sched_ssid) {
 779                                 ssid = ssid->next;
 780                                 break;
 781                         }
 782                         ssid = ssid->next;
 783                 }
 784         }
 785
 786         if (!ssid || !wpa_s->prev_sched_ssid) {
 787                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
 788
 789                 wpa_s->sched_scan_interval = 10;
 790                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
 791                 wpa_s->first_sched_scan = 1;
 792                 ssid = wpa_s->conf->ssid;
 793                 wpa_s->prev_sched_ssid = ssid;
 794         }
 795
 796         if (wildcard) {
 797                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
 798                 params.num_ssids++;
 799         }
 800
 801         while (ssid) {
 802                 if (ssid->disabled)
 803                         goto next;
 804
 805                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
 806                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
 807                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
 808                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 809                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
 810                                   ssid->ssid, ssid->ssid_len);
 811                         params.filter_ssids[params.num_filter_ssids].ssid_len =
 812                                 ssid->ssid_len;
 813                         params.num_filter_ssids++;
 814                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
 815                 {
 816                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
 817                                 "filter for sched_scan - drop filter");
 818                         os_free(params.filter_ssids);
 819                         params.filter_ssids = NULL;
 820                         params.num_filter_ssids = 0;
 821                 }
 822
 823                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
 824                         if (params.num_ssids == max_sched_scan_ssids)
 825                                 break; /* only room for broadcast SSID */
 826                         wpa_dbg(wpa_s, MSG_DEBUG,
 827                                 "add to active scan ssid: %s",
 828                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 829                         params.ssids[params.num_ssids].ssid =
 830                                 ssid->ssid;
 831                         params.ssids[params.num_ssids].ssid_len =
 832                                 ssid->ssid_len;
 833                         params.num_ssids++;
 834                         if (params.num_ssids >= max_sched_scan_ssids) {
 835                                 wpa_s->prev_sched_ssid = ssid;
 836                                 break;
 837                         }
 838                 }
 839
 840         next:
 841                 wpa_s->prev_sched_ssid = ssid;
 842                 ssid = ssid->next;
 843         }
 844
 845         if (params.num_filter_ssids == 0) {
 846                 os_free(params.filter_ssids);
 847                 params.filter_ssids = NULL;
 848         }
 849
 850         if (wpa_s->wps)
 851                 wps_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 852
 853         if (ssid || !wpa_s->first_sched_scan) {
 854                 wpa_dbg(wpa_s, MSG_DEBUG,
 855                         "Starting sched scan: interval %d (no timeout)",
 856                         wpa_s->sched_scan_interval);
 857         } else {
 858                 wpa_dbg(wpa_s, MSG_DEBUG,
 859                         "Starting sched scan: interval %d timeout %d",
 860                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
 861         }
 862
 863         ret = wpa_supplicant_start_sched_scan(wpa_s, &params,
 864                                               wpa_s->sched_scan_interval);
 865         wpabuf_free(wps_ie);
 866         os_free(params.filter_ssids);
 867         if (ret) {
 868                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
 869                 if (prev_state != wpa_s->wpa_state)
 870                         wpa_supplicant_set_state(wpa_s, prev_state);
 871                 return ret;
 872         }
 873
 874         /* If we have more SSIDs to scan, add a timeout so we scan them too */
 875         if (ssid || !wpa_s->first_sched_scan) {
 876                 wpa_s->sched_scan_timed_out = 0;
 877                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
 878                                        wpa_supplicant_sched_scan_timeout,
 879                                        wpa_s, NULL);
 880                 wpa_s->first_sched_scan = 0;
 881                 wpa_s->sched_scan_timeout /= 2;
 882                 wpa_s->sched_scan_interval *= 2;
 883         }
 884
 885         return 0;
 886 }
 887
 888
 889 /**
 890  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
 891  * @wpa_s: Pointer to wpa_supplicant data
 892  *
 893  * This function is used to cancel a scan request scheduled with
 894  * wpa_supplicant_req_scan().
 895  */
 896 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 897 {
 898         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 899         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 900 }
 901
 902
 903 /**
 904  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
 905  * @wpa_s: Pointer to wpa_supplicant data
 906  *
 907  * This function is used to stop a periodic scheduled scan.
 908  */
 909 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
 910 {
 911         if (!wpa_s->sched_scanning)
 912                 return;
 913
 914         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
 915         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
 916         wpa_supplicant_stop_sched_scan(wpa_s);
 917 }
 918
 919
 920 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
 921                                     int scanning)
 922 {
 923         if (wpa_s->scanning != scanning) {
 924                 wpa_s->scanning = scanning;
 925                 wpas_notify_scanning(wpa_s);
 926         }
 927 }
 928
 929
 930 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
 931 {
 932         int rate = 0;
 933         const u8 *ie;
 934         int i;
 935
 936         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
 937         for (i = 0; ie && i < ie[1]; i++) {
 938                 if ((ie[i + 2] & 0x7f) > rate)
 939                         rate = ie[i + 2] & 0x7f;
 940         }
 941
 942         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
 943         for (i = 0; ie && i < ie[1]; i++) {
 944                 if ((ie[i + 2] & 0x7f) > rate)
 945                         rate = ie[i + 2] & 0x7f;
 946         }
 947
 948         return rate;
 949 }
 950
 951
 952 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
 953 {
 954         const u8 *end, *pos;
 955
 956         pos = (const u8 *) (res + 1);
 957         end = pos + res->ie_len;
 958
 959         while (pos + 1 < end) {
 960                 if (pos + 2 + pos[1] > end)
 961                         break;
 962                 if (pos[0] == ie)
 963                         return pos;
 964                 pos += 2 + pos[1];
 965         }
 966
 967         return NULL;
 968 }
 969
 970
 971 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
 972                                   u32 vendor_type)
 973 {
 974         const u8 *end, *pos;
 975
 976         pos = (const u8 *) (res + 1);
 977         end = pos + res->ie_len;
 978
 979         while (pos + 1 < end) {
 980                 if (pos + 2 + pos[1] > end)
 981                         break;
 982                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
 983                     vendor_type == WPA_GET_BE32(&pos[2]))
 984                         return pos;
 985                 pos += 2 + pos[1];
 986         }
 987
 988         return NULL;
 989 }
 990
 991
 992 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
 993                                              u32 vendor_type)
 994 {
 995         struct wpabuf *buf;
 996         const u8 *end, *pos;
 997
 998         buf = wpabuf_alloc(res->ie_len);
 999         if (buf == NULL)
1000                 return NULL;
1001
1002         pos = (const u8 *) (res + 1);
1003         end = pos + res->ie_len;
1004
1005         while (pos + 1 < end) {
1006                 if (pos + 2 + pos[1] > end)
1007                         break;
1008                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1009                     vendor_type == WPA_GET_BE32(&pos[2]))
1010                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1011                 pos += 2 + pos[1];
1012         }
1013
1014         if (wpabuf_len(buf) == 0) {
1015                 wpabuf_free(buf);
1016                 buf = NULL;
1017         }
1018
1019         return buf;
1020 }
1021
1022
1023 struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
1024         const struct wpa_scan_res *res, u32 vendor_type)
1025 {
1026         struct wpabuf *buf;
1027         const u8 *end, *pos;
1028
1029         if (res->beacon_ie_len == 0)
1030                 return NULL;
1031         buf = wpabuf_alloc(res->beacon_ie_len);
1032         if (buf == NULL)
1033                 return NULL;
1034
1035         pos = (const u8 *) (res + 1);
1036         pos += res->ie_len;
1037         end = pos + res->beacon_ie_len;
1038
1039         while (pos + 1 < end) {
1040                 if (pos + 2 + pos[1] > end)
1041                         break;
1042                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1043                     vendor_type == WPA_GET_BE32(&pos[2]))
1044                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1045                 pos += 2 + pos[1];
1046         }
1047
1048         if (wpabuf_len(buf) == 0) {
1049                 wpabuf_free(buf);
1050                 buf = NULL;
1051         }
1052
1053         return buf;
1054 }
1055
1056
1057 /*
1058  * Channels with a great SNR can operate at full rate. What is a great SNR?
1059  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1060  * rule of thumb is that any SNR above 20 is good." This one
1061  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1062  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1063  * conservative value.
1064  */
1065 #define GREAT_SNR 30
1066
1067 /* Compare function for sorting scan results. Return >0 if @b is considered
1068  * better. */
1069 static int wpa_scan_result_compar(const void *a, const void *b)
1070 {
1071 #define IS_5GHZ(n) (n > 4000)
1072 #define MIN(a,b) a < b ? a : b
1073         struct wpa_scan_res **_wa = (void *) a;
1074         struct wpa_scan_res **_wb = (void *) b;
1075         struct wpa_scan_res *wa = *_wa;
1076         struct wpa_scan_res *wb = *_wb;
1077         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1078         int snr_a, snr_b;
1079
1080         /* WPA/WPA2 support preferred */
1081         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1082                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1083         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1084                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1085
1086         if (wpa_b && !wpa_a)
1087                 return 1;
1088         if (!wpa_b && wpa_a)
1089                 return -1;
1090
1091         /* privacy support preferred */
1092         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1093             (wb->caps & IEEE80211_CAP_PRIVACY))
1094                 return 1;
1095         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1096             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1097                 return -1;
1098
1099         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1100             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1101                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1102                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1103         } else {
1104                 /* Not suitable information to calculate SNR, so use level */
1105                 snr_a = wa->level;
1106                 snr_b = wb->level;
1107         }
1108
1109         /* best/max rate preferred if SNR close enough */
1110         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1111             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1112                 maxrate_a = wpa_scan_get_max_rate(wa);
1113                 maxrate_b = wpa_scan_get_max_rate(wb);
1114                 if (maxrate_a != maxrate_b)
1115                         return maxrate_b - maxrate_a;
1116                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1117                         return IS_5GHZ(wa->freq) ? -1 : 1;
1118         }
1119
1120         /* use freq for channel preference */
1121
1122         /* all things being equal, use SNR; if SNRs are
1123          * identical, use quality values since some drivers may only report
1124          * that value and leave the signal level zero */
1125         if (snr_b == snr_a)
1126                 return wb->qual - wa->qual;
1127         return snr_b - snr_a;
1128 #undef MIN
1129 #undef IS_5GHZ
1130 }
1131
1132
1133 #ifdef CONFIG_WPS
1134 /* Compare function for sorting scan results when searching a WPS AP for
1135  * provisioning. Return >0 if @b is considered better. */
1136 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1137 {
1138         struct wpa_scan_res **_wa = (void *) a;
1139         struct wpa_scan_res **_wb = (void *) b;
1140         struct wpa_scan_res *wa = *_wa;
1141         struct wpa_scan_res *wb = *_wb;
1142         int uses_wps_a, uses_wps_b;
1143         struct wpabuf *wps_a, *wps_b;
1144         int res;
1145
1146         /* Optimization - check WPS IE existence before allocated memory and
1147          * doing full reassembly. */
1148         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1149         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1150         if (uses_wps_a && !uses_wps_b)
1151                 return -1;
1152         if (!uses_wps_a && uses_wps_b)
1153                 return 1;
1154
1155         if (uses_wps_a && uses_wps_b) {
1156                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1157                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1158                 res = wps_ap_priority_compar(wps_a, wps_b);
1159                 wpabuf_free(wps_a);
1160                 wpabuf_free(wps_b);
1161                 if (res)
1162                         return res;
1163         }
1164
1165         /*
1166          * Do not use current AP security policy as a sorting criteria during
1167          * WPS provisioning step since the AP may get reconfigured at the
1168          * completion of provisioning.
1169          */
1170
1171         /* all things being equal, use signal level; if signal levels are
1172          * identical, use quality values since some drivers may only report
1173          * that value and leave the signal level zero */
1174         if (wb->level == wa->level)
1175                 return wb->qual - wa->qual;
1176         return wb->level - wa->level;
1177 }
1178 #endif /* CONFIG_WPS */
1179
1180
1181 static void dump_scan_res(struct wpa_scan_results *scan_res)
1182 {
1183 #ifndef CONFIG_NO_STDOUT_DEBUG
1184         size_t i;
1185
1186         if (scan_res->res == NULL || scan_res->num == 0)
1187                 return;
1188
1189         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1190
1191         for (i = 0; i < scan_res->num; i++) {
1192                 struct wpa_scan_res *r = scan_res->res[i];
1193                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1194                     == WPA_SCAN_LEVEL_DBM) {
1195                         int snr = r->level - r->noise;
1196                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1197                                    "noise=%d level=%d snr=%d%s flags=0x%x",
1198                                    MAC2STR(r->bssid), r->freq, r->qual,
1199                                    r->noise, r->level, snr,
1200                                    snr >= GREAT_SNR ? "*" : "", r->flags);
1201                 } else {
1202                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1203                                    "noise=%d level=%d flags=0x%x",
1204                                    MAC2STR(r->bssid), r->freq, r->qual,
1205                                    r->noise, r->level, r->flags);
1206                 }
1207         }
1208 #endif /* CONFIG_NO_STDOUT_DEBUG */
1209 }
1210
1211
1212 /**
1213  * wpa_supplicant_get_scan_results - Get scan results
1214  * @wpa_s: Pointer to wpa_supplicant data
1215  * @info: Information about what was scanned or %NULL if not available
1216  * @new_scan: Whether a new scan was performed
1217  * Returns: Scan results, %NULL on failure
1218  *
1219  * This function request the current scan results from the driver and updates
1220  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1221  * results with wpa_scan_results_free().
1222  */
1223 struct wpa_scan_results *
1224 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1225                                 struct scan_info *info, int new_scan)
1226 {
1227         struct wpa_scan_results *scan_res;
1228         size_t i;
1229         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1230
1231         scan_res = wpa_drv_get_scan_results2(wpa_s);
1232         if (scan_res == NULL) {
1233                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1234                 return NULL;
1235         }
1236
1237 #ifdef CONFIG_WPS
1238         if (wpas_wps_in_progress(wpa_s)) {
1239                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1240                         "provisioning rules");
1241                 compar = wpa_scan_result_wps_compar;
1242         }
1243 #endif /* CONFIG_WPS */
1244
1245         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1246               compar);
1247         dump_scan_res(scan_res);
1248
1249         wpa_bss_update_start(wpa_s);
1250         for (i = 0; i < scan_res->num; i++)
1251                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
1252         wpa_bss_update_end(wpa_s, info, new_scan);
1253
1254         return scan_res;
1255 }
1256
1257
1258 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1259 {
1260         struct wpa_scan_results *scan_res;
1261         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1262         if (scan_res == NULL)
1263                 return -1;
1264         wpa_scan_results_free(scan_res);
1265
1266         return 0;
1267 }