wpa_supplicant/scan.c

   1 /*
   2  * WPA Supplicant - Scanning
   3  * Copyright (c) 2003-2012, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "utils/includes.h"
  10
  11 #include "utils/common.h"
  12 #include "utils/eloop.h"
  13 #include "common/ieee802_11_defs.h"
  14 #include "common/wpa_ctrl.h"
  15 #include "config.h"
  16 #include "wpa_supplicant_i.h"
  17 #include "driver_i.h"
  18 #include "wps_supplicant.h"
  19 #include "p2p_supplicant.h"
  20 #include "p2p/p2p.h"
  21 #include "hs20_supplicant.h"
  22 #include "notify.h"
  23 #include "bss.h"
  24 #include "gas_query.h"
  25 #include "scan.h"
  26
  27
  28 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  29 {
  30         struct wpa_ssid *ssid;
  31         union wpa_event_data data;
  32
  33         ssid = wpa_supplicant_get_ssid(wpa_s);
  34         if (ssid == NULL)
  35                 return;
  36
  37         if (wpa_s->current_ssid == NULL) {
  38                 wpa_s->current_ssid = ssid;
  39                 if (wpa_s->current_ssid != NULL)
  40                         wpas_notify_network_changed(wpa_s);
  41         }
  42         wpa_supplicant_initiate_eapol(wpa_s);
  43         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
  44                 "network - generating associated event");
  45         os_memset(&data, 0, sizeof(data));
  46         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  47 }
  48
  49
  50 #ifdef CONFIG_WPS
  51 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
  52                            enum wps_request_type *req_type)
  53 {
  54         struct wpa_ssid *ssid;
  55         int wps = 0;
  56
  57         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
  58                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  59                         continue;
  60
  61                 wps = 1;
  62                 *req_type = wpas_wps_get_req_type(ssid);
  63                 if (!ssid->eap.phase1)
  64                         continue;
  65
  66                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  67                         return 2;
  68         }
  69
  70 #ifdef CONFIG_P2P
  71         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
  72             !wpa_s->conf->p2p_disabled) {
  73                 wpa_s->wps->dev.p2p = 1;
  74                 if (!wps) {
  75                         wps = 1;
  76                         *req_type = WPS_REQ_ENROLLEE_INFO;
  77                 }
  78         }
  79 #endif /* CONFIG_P2P */
  80
  81         return wps;
  82 }
  83 #endif /* CONFIG_WPS */
  84
  85
  86 /**
  87  * wpa_supplicant_enabled_networks - Check whether there are enabled networks
  88  * @wpa_s: Pointer to wpa_supplicant data
  89  * Returns: 0 if no networks are enabled, >0 if networks are enabled
  90  *
  91  * This function is used to figure out whether any networks (or Interworking
  92  * with enabled credentials and auto_interworking) are present in the current
  93  * configuration.
  94  */
  95 int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
  96 {
  97         struct wpa_ssid *ssid = wpa_s->conf->ssid;
  98         int count = 0, disabled = 0;
  99         while (ssid) {
 100                 if (!wpas_network_disabled(wpa_s, ssid))
 101                         count++;
 102                 else
 103                         disabled++;
 104                 ssid = ssid->next;
 105         }
 106         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 107             wpa_s->conf->auto_interworking)
 108                 count++;
 109         if (count == 0 && disabled > 0) {
 110                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
 111                         "networks)", disabled);
 112         }
 113         return count;
 114 }
 115
 116
 117 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
 118                                      struct wpa_ssid *ssid)
 119 {
 120         while (ssid) {
 121                 if (!wpas_network_disabled(wpa_s, ssid))
 122                         break;
 123                 ssid = ssid->next;
 124         }
 125
 126         /* ap_scan=2 mode - try to associate with each SSID. */
 127         if (ssid == NULL) {
 128                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 129                         "end of scan list - go back to beginning");
 130                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 131                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 132                 return;
 133         }
 134         if (ssid->next) {
 135                 /* Continue from the next SSID on the next attempt. */
 136                 wpa_s->prev_scan_ssid = ssid;
 137         } else {
 138                 /* Start from the beginning of the SSID list. */
 139                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 140         }
 141         wpa_supplicant_associate(wpa_s, NULL, ssid);
 142 }
 143
 144
 145 static int int_array_len(const int *a)
 146 {
 147         int i;
 148         for (i = 0; a && a[i]; i++)
 149                 ;
 150         return i;
 151 }
 152
 153
 154 static void int_array_concat(int **res, const int *a)
 155 {
 156         int reslen, alen, i;
 157         int *n;
 158
 159         reslen = int_array_len(*res);
 160         alen = int_array_len(a);
 161
 162         n = os_realloc_array(*res, reslen + alen + 1, sizeof(int));
 163         if (n == NULL) {
 164                 os_free(*res);
 165                 *res = NULL;
 166                 return;
 167         }
 168         for (i = 0; i <= alen; i++)
 169                 n[reslen + i] = a[i];
 170         *res = n;
 171 }
 172
 173
 174 static int freq_cmp(const void *a, const void *b)
 175 {
 176         int _a = *(int *) a;
 177         int _b = *(int *) b;
 178
 179         if (_a == 0)
 180                 return 1;
 181         if (_b == 0)
 182                 return -1;
 183         return _a - _b;
 184 }
 185
 186
 187 static void int_array_sort_unique(int *a)
 188 {
 189         int alen;
 190         int i, j;
 191
 192         if (a == NULL)
 193                 return;
 194
 195         alen = int_array_len(a);
 196         qsort(a, alen, sizeof(int), freq_cmp);
 197
 198         i = 0;
 199         j = 1;
 200         while (a[i] && a[j]) {
 201                 if (a[i] == a[j]) {
 202                         j++;
 203                         continue;
 204                 }
 205                 a[++i] = a[j++];
 206         }
 207         if (a[i])
 208                 i++;
 209         a[i] = 0;
 210 }
 211
 212
 213 /**
 214  * wpa_supplicant_trigger_scan - Request driver to start a scan
 215  * @wpa_s: Pointer to wpa_supplicant data
 216  * @params: Scan parameters
 217  * Returns: 0 on success, -1 on failure
 218  */
 219 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 220                                 struct wpa_driver_scan_params *params)
 221 {
 222         int ret;
 223
 224         wpa_supplicant_notify_scanning(wpa_s, 1);
 225
 226         ret = wpa_drv_scan(wpa_s, params);
 227         if (ret) {
 228                 wpa_supplicant_notify_scanning(wpa_s, 0);
 229                 wpas_notify_scan_done(wpa_s, 0);
 230         } else {
 231                 os_get_time(&wpa_s->scan_trigger_time);
 232                 wpa_s->scan_runs++;
 233                 wpa_s->normal_scans++;
 234         }
 235
 236         return ret;
 237 }
 238
 239
 240 static void
 241 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 242 {
 243         struct wpa_supplicant *wpa_s = eloop_ctx;
 244
 245         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 246
 247         if (wpa_supplicant_req_sched_scan(wpa_s))
 248                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 249 }
 250
 251
 252 static void
 253 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 254 {
 255         struct wpa_supplicant *wpa_s = eloop_ctx;
 256
 257         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 258
 259         wpa_s->sched_scan_timed_out = 1;
 260         wpa_supplicant_cancel_sched_scan(wpa_s);
 261 }
 262
 263
 264 static int
 265 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 266                                 struct wpa_driver_scan_params *params,
 267                                 int interval)
 268 {
 269         int ret;
 270
 271         wpa_supplicant_notify_scanning(wpa_s, 1);
 272         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 273         if (ret)
 274                 wpa_supplicant_notify_scanning(wpa_s, 0);
 275         else
 276                 wpa_s->sched_scanning = 1;
 277
 278         return ret;
 279 }
 280
 281
 282 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 283 {
 284         int ret;
 285
 286         ret = wpa_drv_stop_sched_scan(wpa_s);
 287         if (ret) {
 288                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 289                 /* TODO: what to do if stopping fails? */
 290                 return -1;
 291         }
 292
 293         return ret;
 294 }
 295
 296
 297 static struct wpa_driver_scan_filter *
 298 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 299 {
 300         struct wpa_driver_scan_filter *ssids;
 301         struct wpa_ssid *ssid;
 302         size_t count;
 303
 304         *num_ssids = 0;
 305         if (!conf->filter_ssids)
 306                 return NULL;
 307
 308         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 309                 if (ssid->ssid && ssid->ssid_len)
 310                         count++;
 311         }
 312         if (count == 0)
 313                 return NULL;
 314         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 315         if (ssids == NULL)
 316                 return NULL;
 317
 318         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 319                 if (!ssid->ssid || !ssid->ssid_len)
 320                         continue;
 321                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 322                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 323                 (*num_ssids)++;
 324         }
 325
 326         return ssids;
 327 }
 328
 329
 330 static void wpa_supplicant_optimize_freqs(
 331         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 332 {
 333 #ifdef CONFIG_P2P
 334         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 335             wpa_s->go_params) {
 336                 /* Optimize provisioning state scan based on GO information */
 337                 if (wpa_s->p2p_in_provisioning < 5 &&
 338                     wpa_s->go_params->freq > 0) {
 339                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 340                                 "preferred frequency %d MHz",
 341                                 wpa_s->go_params->freq);
 342                         params->freqs = os_zalloc(2 * sizeof(int));
 343                         if (params->freqs)
 344                                 params->freqs[0] = wpa_s->go_params->freq;
 345                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 346                            wpa_s->go_params->freq_list[0]) {
 347                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 348                                 "channels");
 349                         int_array_concat(&params->freqs,
 350                                          wpa_s->go_params->freq_list);
 351                         if (params->freqs)
 352                                 int_array_sort_unique(params->freqs);
 353                 }
 354                 wpa_s->p2p_in_provisioning++;
 355         }
 356 #endif /* CONFIG_P2P */
 357
 358 #ifdef CONFIG_WPS
 359         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 360                 /*
 361                  * Optimize post-provisioning scan based on channel used
 362                  * during provisioning.
 363                  */
 364                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 365                         "that was used during provisioning", wpa_s->wps_freq);
 366                 params->freqs = os_zalloc(2 * sizeof(int));
 367                 if (params->freqs)
 368                         params->freqs[0] = wpa_s->wps_freq;
 369                 wpa_s->after_wps--;
 370         }
 371
 372         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 373         {
 374                 /* Optimize provisioning scan based on already known channel */
 375                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 376                         wpa_s->wps_freq);
 377                 params->freqs = os_zalloc(2 * sizeof(int));
 378                 if (params->freqs)
 379                         params->freqs[0] = wpa_s->wps_freq;
 380                 wpa_s->known_wps_freq = 0; /* only do this once */
 381         }
 382 #endif /* CONFIG_WPS */
 383 }
 384
 385
 386 #ifdef CONFIG_INTERWORKING
 387 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 388                                            struct wpabuf *buf)
 389 {
 390         if (wpa_s->conf->interworking == 0)
 391                 return;
 392
 393         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 394         wpabuf_put_u8(buf, 4);
 395         wpabuf_put_u8(buf, 0x00);
 396         wpabuf_put_u8(buf, 0x00);
 397         wpabuf_put_u8(buf, 0x00);
 398         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 399
 400         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 401         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 402                       1 + ETH_ALEN);
 403         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 404         /* No Venue Info */
 405         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 406                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 407 }
 408 #endif /* CONFIG_INTERWORKING */
 409
 410
 411 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
 412 {
 413         struct wpabuf *extra_ie = NULL;
 414 #ifdef CONFIG_WPS
 415         int wps = 0;
 416         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 417 #endif /* CONFIG_WPS */
 418
 419 #ifdef CONFIG_INTERWORKING
 420         if (wpa_s->conf->interworking &&
 421             wpabuf_resize(&extra_ie, 100) == 0)
 422                 wpas_add_interworking_elements(wpa_s, extra_ie);
 423 #endif /* CONFIG_INTERWORKING */
 424
 425 #ifdef CONFIG_WPS
 426         wps = wpas_wps_in_use(wpa_s, &req_type);
 427
 428         if (wps) {
 429                 struct wpabuf *wps_ie;
 430                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
 431                                                 DEV_PW_DEFAULT,
 432                                                 &wpa_s->wps->dev,
 433                                                 wpa_s->wps->uuid, req_type,
 434                                                 0, NULL);
 435                 if (wps_ie) {
 436                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 437                                 wpabuf_put_buf(extra_ie, wps_ie);
 438                         wpabuf_free(wps_ie);
 439                 }
 440         }
 441
 442 #ifdef CONFIG_P2P
 443         if (wps) {
 444                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 445                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 446                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 447         }
 448 #endif /* CONFIG_P2P */
 449
 450 #endif /* CONFIG_WPS */
 451
 452 #ifdef CONFIG_HS20
 453         if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
 454                 wpas_hs20_add_indication(extra_ie);
 455 #endif /* CONFIG_HS20 */
 456
 457         return extra_ie;
 458 }
 459
 460
 461 #ifdef CONFIG_P2P
 462
 463 /*
 464  * Check whether there are any enabled networks or credentials that could be
 465  * used for a non-P2P connection.
 466  */
 467 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
 468 {
 469         struct wpa_ssid *ssid;
 470
 471         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 472                 if (wpas_network_disabled(wpa_s, ssid))
 473                         continue;
 474                 if (!ssid->p2p_group)
 475                         return 1;
 476         }
 477
 478         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 479             wpa_s->conf->auto_interworking)
 480                 return 1;
 481
 482         return 0;
 483 }
 484
 485 #endif /* CONFIG_P2P */
 486
 487
 488 static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
 489                                           u16 num_modes,
 490                                           enum hostapd_hw_mode mode)
 491 {
 492         u16 i;
 493
 494         for (i = 0; i < num_modes; i++) {
 495                 if (modes[i].mode == mode)
 496                         return &modes[i];
 497         }
 498
 499         return NULL;
 500 }
 501
 502
 503 static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
 504                                         enum hostapd_hw_mode band,
 505                                         struct wpa_driver_scan_params *params)
 506 {
 507         /* Include only supported channels for the specified band */
 508         struct hostapd_hw_modes *mode;
 509         int count, i;
 510
 511         mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
 512         if (mode == NULL) {
 513                 /* No channels supported in this band - use empty list */
 514                 params->freqs = os_zalloc(sizeof(int));
 515                 return;
 516         }
 517
 518         params->freqs = os_zalloc((mode->num_channels + 1) * sizeof(int));
 519         if (params->freqs == NULL)
 520                 return;
 521         for (count = 0, i = 0; i < mode->num_channels; i++) {
 522                 if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
 523                         continue;
 524                 params->freqs[count++] = mode->channels[i].freq;
 525         }
 526 }
 527
 528
 529 static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
 530                                    struct wpa_driver_scan_params *params)
 531 {
 532         if (wpa_s->hw.modes == NULL)
 533                 return; /* unknown what channels the driver supports */
 534         if (params->freqs)
 535                 return; /* already using a limited channel set */
 536         if (wpa_s->setband == WPA_SETBAND_5G)
 537                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
 538                                             params);
 539         else if (wpa_s->setband == WPA_SETBAND_2G)
 540                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
 541                                             params);
 542 }
 543
 544
 545 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 546 {
 547         struct wpa_supplicant *wpa_s = eloop_ctx;
 548         struct wpa_ssid *ssid;
 549         enum scan_req_type scan_req = NORMAL_SCAN_REQ;
 550         int ret;
 551         struct wpabuf *extra_ie = NULL;
 552         struct wpa_driver_scan_params params;
 553         struct wpa_driver_scan_params *scan_params;
 554         size_t max_ssids;
 555         enum wpa_states prev_state;
 556
 557         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 558                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 559                 wpas_p2p_continue_after_scan(wpa_s);
 560                 return;
 561         }
 562
 563         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
 564                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
 565                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 566                 wpas_p2p_continue_after_scan(wpa_s);
 567                 return;
 568         }
 569
 570         if (!wpa_supplicant_enabled_networks(wpa_s) &&
 571             wpa_s->scan_req == NORMAL_SCAN_REQ) {
 572                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 573                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 574                 wpas_p2p_continue_after_scan(wpa_s);
 575                 return;
 576         }
 577
 578         if (wpa_s->conf->ap_scan != 0 &&
 579             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 580                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 581                         "overriding ap_scan configuration");
 582                 wpa_s->conf->ap_scan = 0;
 583                 wpas_notify_ap_scan_changed(wpa_s);
 584         }
 585
 586         if (wpa_s->conf->ap_scan == 0) {
 587                 wpa_supplicant_gen_assoc_event(wpa_s);
 588                 return;
 589         }
 590
 591 #ifdef CONFIG_P2P
 592         if (wpas_p2p_in_progress(wpa_s) || wpas_wpa_is_in_progress(wpa_s, 0)) {
 593                 if (wpa_s->sta_scan_pending &&
 594                     wpas_p2p_in_progress(wpa_s) == 2 &&
 595                     wpa_s->global->p2p_cb_on_scan_complete) {
 596                         wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
 597                                 "mode scan during P2P search");
 598                 } else {
 599                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 600                                 "while P2P operation is in progress");
 601                         wpa_s->sta_scan_pending = 1;
 602                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 603                         return;
 604                 }
 605         }
 606 #endif /* CONFIG_P2P */
 607
 608 #ifdef CONFIG_GAS
 609         if (gas_query_in_progress(wpa_s->gas)) {
 610                 wpa_dbg(wpa_s, MSG_DEBUG, "Delay scan while GAS query is in progress");
 611                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 612                 return;
 613         }
 614 #endif /* CONFIG_GAS */
 615
 616         if (wpa_s->conf->ap_scan == 2)
 617                 max_ssids = 1;
 618         else {
 619                 max_ssids = wpa_s->max_scan_ssids;
 620                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 621                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 622         }
 623
 624         scan_req = wpa_s->scan_req;
 625         wpa_s->scan_req = NORMAL_SCAN_REQ;
 626
 627         os_memset(&params, 0, sizeof(params));
 628
 629         prev_state = wpa_s->wpa_state;
 630         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 631             wpa_s->wpa_state == WPA_INACTIVE)
 632                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 633
 634         /*
 635          * If autoscan has set its own scanning parameters
 636          */
 637         if (wpa_s->autoscan_params != NULL) {
 638                 scan_params = wpa_s->autoscan_params;
 639                 goto scan;
 640         }
 641
 642         if (scan_req != MANUAL_SCAN_REQ && wpa_s->connect_without_scan) {
 643                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 644                         if (ssid == wpa_s->connect_without_scan)
 645                                 break;
 646                 }
 647                 wpa_s->connect_without_scan = NULL;
 648                 if (ssid) {
 649                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 650                                    "without scan step");
 651                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 652                         return;
 653                 }
 654         }
 655
 656 #ifdef CONFIG_P2P
 657         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
 658             wpa_s->go_params) {
 659                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during P2P group formation (p2p_in_provisioning=%d show_group_started=%d)",
 660                            wpa_s->p2p_in_provisioning,
 661                            wpa_s->show_group_started);
 662                 params.ssids[0].ssid = wpa_s->go_params->ssid;
 663                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
 664                 params.num_ssids = 1;
 665                 goto ssid_list_set;
 666         }
 667 #endif /* CONFIG_P2P */
 668
 669         /* Find the starting point from which to continue scanning */
 670         ssid = wpa_s->conf->ssid;
 671         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 672                 while (ssid) {
 673                         if (ssid == wpa_s->prev_scan_ssid) {
 674                                 ssid = ssid->next;
 675                                 break;
 676                         }
 677                         ssid = ssid->next;
 678                 }
 679         }
 680
 681         if (scan_req != MANUAL_SCAN_REQ && wpa_s->conf->ap_scan == 2) {
 682                 wpa_s->connect_without_scan = NULL;
 683                 wpa_s->prev_scan_wildcard = 0;
 684                 wpa_supplicant_assoc_try(wpa_s, ssid);
 685                 return;
 686         } else if (wpa_s->conf->ap_scan == 2) {
 687                 /*
 688                  * User-initiated scan request in ap_scan == 2; scan with
 689                  * wildcard SSID.
 690                  */
 691                 ssid = NULL;
 692         } else {
 693                 struct wpa_ssid *start = ssid, *tssid;
 694                 int freqs_set = 0;
 695                 if (ssid == NULL && max_ssids > 1)
 696                         ssid = wpa_s->conf->ssid;
 697                 while (ssid) {
 698                         if (!wpas_network_disabled(wpa_s, ssid) &&
 699                             ssid->scan_ssid) {
 700                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 701                                                   ssid->ssid, ssid->ssid_len);
 702                                 params.ssids[params.num_ssids].ssid =
 703                                         ssid->ssid;
 704                                 params.ssids[params.num_ssids].ssid_len =
 705                                         ssid->ssid_len;
 706                                 params.num_ssids++;
 707                                 if (params.num_ssids + 1 >= max_ssids)
 708                                         break;
 709                         }
 710                         ssid = ssid->next;
 711                         if (ssid == start)
 712                                 break;
 713                         if (ssid == NULL && max_ssids > 1 &&
 714                             start != wpa_s->conf->ssid)
 715                                 ssid = wpa_s->conf->ssid;
 716                 }
 717
 718                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 719                         if (wpas_network_disabled(wpa_s, tssid))
 720                                 continue;
 721                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 722                                 int_array_concat(&params.freqs,
 723                                                  tssid->scan_freq);
 724                         } else {
 725                                 os_free(params.freqs);
 726                                 params.freqs = NULL;
 727                         }
 728                         freqs_set = 1;
 729                 }
 730                 int_array_sort_unique(params.freqs);
 731         }
 732
 733         if (ssid && max_ssids == 1) {
 734                 /*
 735                  * If the driver is limited to 1 SSID at a time interleave
 736                  * wildcard SSID scans with specific SSID scans to avoid
 737                  * waiting a long time for a wildcard scan.
 738                  */
 739                 if (!wpa_s->prev_scan_wildcard) {
 740                         params.ssids[0].ssid = NULL;
 741                         params.ssids[0].ssid_len = 0;
 742                         wpa_s->prev_scan_wildcard = 1;
 743                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 744                                 "wildcard SSID (Interleave with specific)");
 745                 } else {
 746                         wpa_s->prev_scan_ssid = ssid;
 747                         wpa_s->prev_scan_wildcard = 0;
 748                         wpa_dbg(wpa_s, MSG_DEBUG,
 749                                 "Starting AP scan for specific SSID: %s",
 750                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 751                 }
 752         } else if (ssid) {
 753                 /* max_ssids > 1 */
 754
 755                 wpa_s->prev_scan_ssid = ssid;
 756                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 757                         "the scan request");
 758                 params.num_ssids++;
 759         } else {
 760                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 761                 params.num_ssids++;
 762                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 763                         "SSID");
 764         }
 765 #ifdef CONFIG_P2P
 766 ssid_list_set:
 767 #endif /* CONFIG_P2P */
 768
 769         wpa_supplicant_optimize_freqs(wpa_s, &params);
 770         extra_ie = wpa_supplicant_extra_ies(wpa_s);
 771
 772         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 773                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 774                         "generated frequency list");
 775                 params.freqs = wpa_s->next_scan_freqs;
 776         } else
 777                 os_free(wpa_s->next_scan_freqs);
 778         wpa_s->next_scan_freqs = NULL;
 779         wpa_setband_scan_freqs(wpa_s, &params);
 780
 781         /* See if user specified frequencies. If so, scan only those. */
 782         if (wpa_s->conf->freq_list && !params.freqs) {
 783                 wpa_dbg(wpa_s, MSG_DEBUG,
 784                         "Optimize scan based on conf->freq_list");
 785                 int_array_concat(&params.freqs, wpa_s->conf->freq_list);
 786         }
 787
 788         /* Use current associated channel? */
 789         if (wpa_s->conf->scan_cur_freq && !params.freqs) {
 790                 unsigned int num = wpa_s->num_multichan_concurrent;
 791
 792                 params.freqs = os_calloc(num + 1, sizeof(int));
 793                 if (params.freqs) {
 794                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
 795                         if (num > 0) {
 796                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the "
 797                                         "current operating channels since "
 798                                         "scan_cur_freq is enabled");
 799                         } else {
 800                                 os_free(params.freqs);
 801                                 params.freqs = NULL;
 802                         }
 803                 }
 804         }
 805
 806         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 807                 wpa_s->conf, &params.num_filter_ssids);
 808         if (extra_ie) {
 809                 params.extra_ies = wpabuf_head(extra_ie);
 810                 params.extra_ies_len = wpabuf_len(extra_ie);
 811         }
 812
 813 #ifdef CONFIG_P2P
 814         if (wpa_s->p2p_in_provisioning ||
 815             (wpa_s->show_group_started && wpa_s->go_params)) {
 816                 /*
 817                  * The interface may not yet be in P2P mode, so we have to
 818                  * explicitly request P2P probe to disable CCK rates.
 819                  */
 820                 params.p2p_probe = 1;
 821         }
 822 #endif /* CONFIG_P2P */
 823
 824         scan_params = &params;
 825
 826 scan:
 827 #ifdef CONFIG_P2P
 828         /*
 829          * If the driver does not support multi-channel concurrency and a
 830          * virtual interface that shares the same radio with the wpa_s interface
 831          * is operating there may not be need to scan other channels apart from
 832          * the current operating channel on the other virtual interface. Filter
 833          * out other channels in case we are trying to find a connection for a
 834          * station interface when we are not configured to prefer station
 835          * connection and a concurrent operation is already in process.
 836          */
 837         if (wpa_s->scan_for_connection && scan_req == NORMAL_SCAN_REQ &&
 838             !scan_params->freqs && !params.freqs &&
 839             wpas_is_p2p_prioritized(wpa_s) &&
 840             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
 841             non_p2p_network_enabled(wpa_s)) {
 842                 unsigned int num = wpa_s->num_multichan_concurrent;
 843
 844                 params.freqs = os_calloc(num + 1, sizeof(int));
 845                 if (params.freqs) {
 846                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
 847                         if (num > 0 && num == wpa_s->num_multichan_concurrent) {
 848                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current operating channels since all channels are already used");
 849                         } else {
 850                                 os_free(params.freqs);
 851                                 params.freqs = NULL;
 852                         }
 853                 }
 854         }
 855 #endif /* CONFIG_P2P */
 856
 857         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
 858
 859         wpabuf_free(extra_ie);
 860         os_free(params.freqs);
 861         os_free(params.filter_ssids);
 862
 863         if (ret) {
 864                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 865                 if (prev_state != wpa_s->wpa_state)
 866                         wpa_supplicant_set_state(wpa_s, prev_state);
 867                 /* Restore scan_req since we will try to scan again */
 868                 wpa_s->scan_req = scan_req;
 869                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 870         } else {
 871                 wpa_s->scan_for_connection = 0;
 872         }
 873 }
 874
 875
 876 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 877 {
 878         struct os_time remaining, new_int;
 879         int cancelled;
 880
 881         cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
 882                                              &remaining);
 883
 884         new_int.sec = sec;
 885         new_int.usec = 0;
 886         if (cancelled && os_time_before(&remaining, &new_int)) {
 887                 new_int.sec = remaining.sec;
 888                 new_int.usec = remaining.usec;
 889         }
 890
 891         if (cancelled) {
 892                 eloop_register_timeout(new_int.sec, new_int.usec,
 893                                        wpa_supplicant_scan, wpa_s, NULL);
 894         }
 895         wpa_s->scan_interval = sec;
 896 }
 897
 898
 899 /**
 900  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 901  * @wpa_s: Pointer to wpa_supplicant data
 902  * @sec: Number of seconds after which to scan
 903  * @usec: Number of microseconds after which to scan
 904  *
 905  * This function is used to schedule a scan for neighboring access points after
 906  * the specified time.
 907  */
 908 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 909 {
 910         if (eloop_deplete_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL))
 911         {
 912                 wpa_dbg(wpa_s, MSG_DEBUG, "Rescheduling scan request: %d sec %d usec",
 913                         sec, usec);
 914                 return;
 915         }
 916
 917         /* If there's at least one network that should be specifically scanned
 918          * then don't cancel the scan and reschedule.  Some drivers do
 919          * background scanning which generates frequent scan results, and that
 920          * causes the specific SSID scan to get continually pushed back and
 921          * never happen, which causes hidden APs to never get probe-scanned.
 922          */
 923         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 924             wpa_s->conf->ap_scan == 1) {
 925                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 926
 927                 while (ssid) {
 928                         if (!wpas_network_disabled(wpa_s, ssid) &&
 929                             ssid->scan_ssid)
 930                                 break;
 931                         ssid = ssid->next;
 932                 }
 933                 if (ssid) {
 934                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 935                                 "ensure that specific SSID scans occur");
 936                         return;
 937                 }
 938         }
 939
 940         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 941                 sec, usec);
 942         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 943         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 944 }
 945
 946
 947 /**
 948  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 949  * @wpa_s: Pointer to wpa_supplicant data
 950  * @sec: Number of seconds after which to scan
 951  * @usec: Number of microseconds after which to scan
 952  * Returns: 0 on success or -1 otherwise
 953  *
 954  * This function is used to schedule periodic scans for neighboring
 955  * access points after the specified time.
 956  */
 957 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 958                                       int sec, int usec)
 959 {
 960         if (!wpa_s->sched_scan_supported)
 961                 return -1;
 962
 963         eloop_register_timeout(sec, usec,
 964                                wpa_supplicant_delayed_sched_scan_timeout,
 965                                wpa_s, NULL);
 966
 967         return 0;
 968 }
 969
 970
 971 /**
 972  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 973  * @wpa_s: Pointer to wpa_supplicant data
 974  * Returns: 0 is sched_scan was started or -1 otherwise
 975  *
 976  * This function is used to schedule periodic scans for neighboring
 977  * access points repeating the scan continuously.
 978  */
 979 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 980 {
 981         struct wpa_driver_scan_params params;
 982         struct wpa_driver_scan_params *scan_params;
 983         enum wpa_states prev_state;
 984         struct wpa_ssid *ssid = NULL;
 985         struct wpabuf *extra_ie = NULL;
 986         int ret;
 987         unsigned int max_sched_scan_ssids;
 988         int wildcard = 0;
 989         int need_ssids;
 990
 991         if (!wpa_s->sched_scan_supported)
 992                 return -1;
 993
 994         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 995                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 996         else
 997                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 998         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
 999                 return -1;
1000
1001         if (wpa_s->sched_scanning) {
1002                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
1003                 return 0;
1004         }
1005
1006         need_ssids = 0;
1007         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
1008                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
1009                         /* Use wildcard SSID to find this network */
1010                         wildcard = 1;
1011                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
1012                            ssid->ssid_len)
1013                         need_ssids++;
1014
1015 #ifdef CONFIG_WPS
1016                 if (!wpas_network_disabled(wpa_s, ssid) &&
1017                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
1018                         /*
1019                          * Normal scan is more reliable and faster for WPS
1020                          * operations and since these are for short periods of
1021                          * time, the benefit of trying to use sched_scan would
1022                          * be limited.
1023                          */
1024                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1025                                 "sched_scan for WPS");
1026                         return -1;
1027                 }
1028 #endif /* CONFIG_WPS */
1029         }
1030         if (wildcard)
1031                 need_ssids++;
1032
1033         if (wpa_s->normal_scans < 3 &&
1034             (need_ssids <= wpa_s->max_scan_ssids ||
1035              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
1036                 /*
1037                  * When normal scan can speed up operations, use that for the
1038                  * first operations before starting the sched_scan to allow
1039                  * user space sleep more. We do this only if the normal scan
1040                  * has functionality that is suitable for this or if the
1041                  * sched_scan does not have better support for multiple SSIDs.
1042                  */
1043                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1044                         "sched_scan for initial scans (normal_scans=%d)",
1045                         wpa_s->normal_scans);
1046                 return -1;
1047         }
1048
1049         os_memset(&params, 0, sizeof(params));
1050
1051         /* If we can't allocate space for the filters, we just don't filter */
1052         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
1053                                         sizeof(struct wpa_driver_scan_filter));
1054
1055         prev_state = wpa_s->wpa_state;
1056         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
1057             wpa_s->wpa_state == WPA_INACTIVE)
1058                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
1059
1060         if (wpa_s->autoscan_params != NULL) {
1061                 scan_params = wpa_s->autoscan_params;
1062                 goto scan;
1063         }
1064
1065         /* Find the starting point from which to continue scanning */
1066         ssid = wpa_s->conf->ssid;
1067         if (wpa_s->prev_sched_ssid) {
1068                 while (ssid) {
1069                         if (ssid == wpa_s->prev_sched_ssid) {
1070                                 ssid = ssid->next;
1071                                 break;
1072                         }
1073                         ssid = ssid->next;
1074                 }
1075         }
1076
1077         if (!ssid || !wpa_s->prev_sched_ssid) {
1078                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
1079                 if (wpa_s->conf->sched_scan_interval)
1080                         wpa_s->sched_scan_interval =
1081                                 wpa_s->conf->sched_scan_interval;
1082                 if (wpa_s->sched_scan_interval == 0)
1083                         wpa_s->sched_scan_interval = 10;
1084                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1085                 wpa_s->first_sched_scan = 1;
1086                 ssid = wpa_s->conf->ssid;
1087                 wpa_s->prev_sched_ssid = ssid;
1088         }
1089
1090         if (wildcard) {
1091                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1092                 params.num_ssids++;
1093         }
1094
1095         while (ssid) {
1096                 if (wpas_network_disabled(wpa_s, ssid))
1097                         goto next;
1098
1099                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
1100                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1101                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1102                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1103                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1104                                   ssid->ssid, ssid->ssid_len);
1105                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1106                                 ssid->ssid_len;
1107                         params.num_filter_ssids++;
1108                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1109                 {
1110                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1111                                 "filter for sched_scan - drop filter");
1112                         os_free(params.filter_ssids);
1113                         params.filter_ssids = NULL;
1114                         params.num_filter_ssids = 0;
1115                 }
1116
1117                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1118                         if (params.num_ssids == max_sched_scan_ssids)
1119                                 break; /* only room for broadcast SSID */
1120                         wpa_dbg(wpa_s, MSG_DEBUG,
1121                                 "add to active scan ssid: %s",
1122                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1123                         params.ssids[params.num_ssids].ssid =
1124                                 ssid->ssid;
1125                         params.ssids[params.num_ssids].ssid_len =
1126                                 ssid->ssid_len;
1127                         params.num_ssids++;
1128                         if (params.num_ssids >= max_sched_scan_ssids) {
1129                                 wpa_s->prev_sched_ssid = ssid;
1130                                 do {
1131                                         ssid = ssid->next;
1132                                 } while (ssid &&
1133                                          (wpas_network_disabled(wpa_s, ssid) ||
1134                                           !ssid->scan_ssid));
1135                                 break;
1136                         }
1137                 }
1138
1139         next:
1140                 wpa_s->prev_sched_ssid = ssid;
1141                 ssid = ssid->next;
1142         }
1143
1144         if (params.num_filter_ssids == 0) {
1145                 os_free(params.filter_ssids);
1146                 params.filter_ssids = NULL;
1147         }
1148
1149         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1150         if (extra_ie) {
1151                 params.extra_ies = wpabuf_head(extra_ie);
1152                 params.extra_ies_len = wpabuf_len(extra_ie);
1153         }
1154
1155         scan_params = &params;
1156
1157 scan:
1158         if (ssid || !wpa_s->first_sched_scan) {
1159                 wpa_dbg(wpa_s, MSG_DEBUG,
1160                         "Starting sched scan: interval %d timeout %d",
1161                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1162         } else {
1163                 wpa_dbg(wpa_s, MSG_DEBUG,
1164                         "Starting sched scan: interval %d (no timeout)",
1165                         wpa_s->sched_scan_interval);
1166         }
1167
1168         wpa_setband_scan_freqs(wpa_s, scan_params);
1169
1170         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1171                                               wpa_s->sched_scan_interval);
1172         wpabuf_free(extra_ie);
1173         os_free(params.filter_ssids);
1174         if (ret) {
1175                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1176                 if (prev_state != wpa_s->wpa_state)
1177                         wpa_supplicant_set_state(wpa_s, prev_state);
1178                 return ret;
1179         }
1180
1181         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1182         if (ssid || !wpa_s->first_sched_scan) {
1183                 wpa_s->sched_scan_timed_out = 0;
1184                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1185                                        wpa_supplicant_sched_scan_timeout,
1186                                        wpa_s, NULL);
1187                 wpa_s->first_sched_scan = 0;
1188                 wpa_s->sched_scan_timeout /= 2;
1189                 wpa_s->sched_scan_interval *= 2;
1190                 if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
1191                         wpa_s->sched_scan_interval = 10;
1192                         wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1193                 }
1194         }
1195
1196         /* If there is no more ssids, start next time from the beginning */
1197         if (!ssid)
1198                 wpa_s->prev_sched_ssid = NULL;
1199
1200         return 0;
1201 }
1202
1203
1204 /**
1205  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1206  * @wpa_s: Pointer to wpa_supplicant data
1207  *
1208  * This function is used to cancel a scan request scheduled with
1209  * wpa_supplicant_req_scan().
1210  */
1211 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1212 {
1213         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1214         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1215         wpas_p2p_continue_after_scan(wpa_s);
1216 }
1217
1218
1219 /**
1220  * wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
1221  * @wpa_s: Pointer to wpa_supplicant data
1222  *
1223  * This function is used to stop a delayed scheduled scan.
1224  */
1225 void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
1226 {
1227         if (!wpa_s->sched_scan_supported)
1228                 return;
1229
1230         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
1231         eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
1232                              wpa_s, NULL);
1233 }
1234
1235
1236 /**
1237  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1238  * @wpa_s: Pointer to wpa_supplicant data
1239  *
1240  * This function is used to stop a periodic scheduled scan.
1241  */
1242 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1243 {
1244         if (!wpa_s->sched_scanning)
1245                 return;
1246
1247         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1248         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1249         wpa_supplicant_stop_sched_scan(wpa_s);
1250 }
1251
1252
1253 /**
1254  * wpa_supplicant_notify_scanning - Indicate possible scan state change
1255  * @wpa_s: Pointer to wpa_supplicant data
1256  * @scanning: Whether scanning is currently in progress
1257  *
1258  * This function is to generate scanning notifycations. It is called whenever
1259  * there may have been a change in scanning (scan started, completed, stopped).
1260  * wpas_notify_scanning() is called whenever the scanning state changed from the
1261  * previously notified state.
1262  */
1263 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1264                                     int scanning)
1265 {
1266         if (wpa_s->scanning != scanning) {
1267                 wpa_s->scanning = scanning;
1268                 wpas_notify_scanning(wpa_s);
1269         }
1270 }
1271
1272
1273 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1274 {
1275         int rate = 0;
1276         const u8 *ie;
1277         int i;
1278
1279         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1280         for (i = 0; ie && i < ie[1]; i++) {
1281                 if ((ie[i + 2] & 0x7f) > rate)
1282                         rate = ie[i + 2] & 0x7f;
1283         }
1284
1285         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1286         for (i = 0; ie && i < ie[1]; i++) {
1287                 if ((ie[i + 2] & 0x7f) > rate)
1288                         rate = ie[i + 2] & 0x7f;
1289         }
1290
1291         return rate;
1292 }
1293
1294
1295 /**
1296  * wpa_scan_get_ie - Fetch a specified information element from a scan result
1297  * @res: Scan result entry
1298  * @ie: Information element identitifier (WLAN_EID_*)
1299  * Returns: Pointer to the information element (id field) or %NULL if not found
1300  *
1301  * This function returns the first matching information element in the scan
1302  * result.
1303  */
1304 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1305 {
1306         const u8 *end, *pos;
1307
1308         pos = (const u8 *) (res + 1);
1309         end = pos + res->ie_len;
1310
1311         while (pos + 1 < end) {
1312                 if (pos + 2 + pos[1] > end)
1313                         break;
1314                 if (pos[0] == ie)
1315                         return pos;
1316                 pos += 2 + pos[1];
1317         }
1318
1319         return NULL;
1320 }
1321
1322
1323 /**
1324  * wpa_scan_get_vendor_ie - Fetch vendor information element from a scan result
1325  * @res: Scan result entry
1326  * @vendor_type: Vendor type (four octets starting the IE payload)
1327  * Returns: Pointer to the information element (id field) or %NULL if not found
1328  *
1329  * This function returns the first matching information element in the scan
1330  * result.
1331  */
1332 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1333                                   u32 vendor_type)
1334 {
1335         const u8 *end, *pos;
1336
1337         pos = (const u8 *) (res + 1);
1338         end = pos + res->ie_len;
1339
1340         while (pos + 1 < end) {
1341                 if (pos + 2 + pos[1] > end)
1342                         break;
1343                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1344                     vendor_type == WPA_GET_BE32(&pos[2]))
1345                         return pos;
1346                 pos += 2 + pos[1];
1347         }
1348
1349         return NULL;
1350 }
1351
1352
1353 /**
1354  * wpa_scan_get_vendor_ie_beacon - Fetch vendor information from a scan result
1355  * @res: Scan result entry
1356  * @vendor_type: Vendor type (four octets starting the IE payload)
1357  * Returns: Pointer to the information element (id field) or %NULL if not found
1358  *
1359  * This function returns the first matching information element in the scan
1360  * result.
1361  *
1362  * This function is like wpa_scan_get_vendor_ie(), but uses IE buffer only
1363  * from Beacon frames instead of either Beacon or Probe Response frames.
1364  */
1365 const u8 * wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res *res,
1366                                          u32 vendor_type)
1367 {
1368         const u8 *end, *pos;
1369
1370         if (res->beacon_ie_len == 0)
1371                 return NULL;
1372
1373         pos = (const u8 *) (res + 1);
1374         pos += res->ie_len;
1375         end = pos + res->beacon_ie_len;
1376
1377         while (pos + 1 < end) {
1378                 if (pos + 2 + pos[1] > end)
1379                         break;
1380                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1381                     vendor_type == WPA_GET_BE32(&pos[2]))
1382                         return pos;
1383                 pos += 2 + pos[1];
1384         }
1385
1386         return NULL;
1387 }
1388
1389
1390 /**
1391  * wpa_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
1392  * @res: Scan result entry
1393  * @vendor_type: Vendor type (four octets starting the IE payload)
1394  * Returns: Pointer to the information element payload or %NULL if not found
1395  *
1396  * This function returns concatenated payload of possibly fragmented vendor
1397  * specific information elements in the scan result. The caller is responsible
1398  * for freeing the returned buffer.
1399  */
1400 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1401                                              u32 vendor_type)
1402 {
1403         struct wpabuf *buf;
1404         const u8 *end, *pos;
1405
1406         buf = wpabuf_alloc(res->ie_len);
1407         if (buf == NULL)
1408                 return NULL;
1409
1410         pos = (const u8 *) (res + 1);
1411         end = pos + res->ie_len;
1412
1413         while (pos + 1 < end) {
1414                 if (pos + 2 + pos[1] > end)
1415                         break;
1416                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1417                     vendor_type == WPA_GET_BE32(&pos[2]))
1418                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1419                 pos += 2 + pos[1];
1420         }
1421
1422         if (wpabuf_len(buf) == 0) {
1423                 wpabuf_free(buf);
1424                 buf = NULL;
1425         }
1426
1427         return buf;
1428 }
1429
1430
1431 /*
1432  * Channels with a great SNR can operate at full rate. What is a great SNR?
1433  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1434  * rule of thumb is that any SNR above 20 is good." This one
1435  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1436  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1437  * conservative value.
1438  */
1439 #define GREAT_SNR 30
1440
1441 /* Compare function for sorting scan results. Return >0 if @b is considered
1442  * better. */
1443 static int wpa_scan_result_compar(const void *a, const void *b)
1444 {
1445 #define IS_5GHZ(n) (n > 4000)
1446 #define MIN(a,b) a < b ? a : b
1447         struct wpa_scan_res **_wa = (void *) a;
1448         struct wpa_scan_res **_wb = (void *) b;
1449         struct wpa_scan_res *wa = *_wa;
1450         struct wpa_scan_res *wb = *_wb;
1451         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1452         int snr_a, snr_b;
1453
1454         /* WPA/WPA2 support preferred */
1455         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1456                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1457         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1458                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1459
1460         if (wpa_b && !wpa_a)
1461                 return 1;
1462         if (!wpa_b && wpa_a)
1463                 return -1;
1464
1465         /* privacy support preferred */
1466         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1467             (wb->caps & IEEE80211_CAP_PRIVACY))
1468                 return 1;
1469         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1470             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1471                 return -1;
1472
1473         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1474             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1475                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1476                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1477         } else {
1478                 /* Not suitable information to calculate SNR, so use level */
1479                 snr_a = wa->level;
1480                 snr_b = wb->level;
1481         }
1482
1483         /* best/max rate preferred if SNR close enough */
1484         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1485             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1486                 maxrate_a = wpa_scan_get_max_rate(wa);
1487                 maxrate_b = wpa_scan_get_max_rate(wb);
1488                 if (maxrate_a != maxrate_b)
1489                         return maxrate_b - maxrate_a;
1490                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1491                         return IS_5GHZ(wa->freq) ? -1 : 1;
1492         }
1493
1494         /* use freq for channel preference */
1495
1496         /* all things being equal, use SNR; if SNRs are
1497          * identical, use quality values since some drivers may only report
1498          * that value and leave the signal level zero */
1499         if (snr_b == snr_a)
1500                 return wb->qual - wa->qual;
1501         return snr_b - snr_a;
1502 #undef MIN
1503 #undef IS_5GHZ
1504 }
1505
1506
1507 #ifdef CONFIG_WPS
1508 /* Compare function for sorting scan results when searching a WPS AP for
1509  * provisioning. Return >0 if @b is considered better. */
1510 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1511 {
1512         struct wpa_scan_res **_wa = (void *) a;
1513         struct wpa_scan_res **_wb = (void *) b;
1514         struct wpa_scan_res *wa = *_wa;
1515         struct wpa_scan_res *wb = *_wb;
1516         int uses_wps_a, uses_wps_b;
1517         struct wpabuf *wps_a, *wps_b;
1518         int res;
1519
1520         /* Optimization - check WPS IE existence before allocated memory and
1521          * doing full reassembly. */
1522         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1523         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1524         if (uses_wps_a && !uses_wps_b)
1525                 return -1;
1526         if (!uses_wps_a && uses_wps_b)
1527                 return 1;
1528
1529         if (uses_wps_a && uses_wps_b) {
1530                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1531                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1532                 res = wps_ap_priority_compar(wps_a, wps_b);
1533                 wpabuf_free(wps_a);
1534                 wpabuf_free(wps_b);
1535                 if (res)
1536                         return res;
1537         }
1538
1539         /*
1540          * Do not use current AP security policy as a sorting criteria during
1541          * WPS provisioning step since the AP may get reconfigured at the
1542          * completion of provisioning.
1543          */
1544
1545         /* all things being equal, use signal level; if signal levels are
1546          * identical, use quality values since some drivers may only report
1547          * that value and leave the signal level zero */
1548         if (wb->level == wa->level)
1549                 return wb->qual - wa->qual;
1550         return wb->level - wa->level;
1551 }
1552 #endif /* CONFIG_WPS */
1553
1554
1555 static void dump_scan_res(struct wpa_scan_results *scan_res)
1556 {
1557 #ifndef CONFIG_NO_STDOUT_DEBUG
1558         size_t i;
1559
1560         if (scan_res->res == NULL || scan_res->num == 0)
1561                 return;
1562
1563         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1564
1565         for (i = 0; i < scan_res->num; i++) {
1566                 struct wpa_scan_res *r = scan_res->res[i];
1567                 u8 *pos;
1568                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1569                     == WPA_SCAN_LEVEL_DBM) {
1570                         int snr = r->level - r->noise;
1571                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1572                                    "noise=%d level=%d snr=%d%s flags=0x%x "
1573                                    "age=%u",
1574                                    MAC2STR(r->bssid), r->freq, r->qual,
1575                                    r->noise, r->level, snr,
1576                                    snr >= GREAT_SNR ? "*" : "", r->flags,
1577                                    r->age);
1578                 } else {
1579                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1580                                    "noise=%d level=%d flags=0x%x age=%u",
1581                                    MAC2STR(r->bssid), r->freq, r->qual,
1582                                    r->noise, r->level, r->flags, r->age);
1583                 }
1584                 pos = (u8 *) (r + 1);
1585                 if (r->ie_len)
1586                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1587                 pos += r->ie_len;
1588                 if (r->beacon_ie_len)
1589                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1590                                     pos, r->beacon_ie_len);
1591         }
1592 #endif /* CONFIG_NO_STDOUT_DEBUG */
1593 }
1594
1595
1596 /**
1597  * wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
1598  * @wpa_s: Pointer to wpa_supplicant data
1599  * @bssid: BSSID to check
1600  * Returns: 0 if the BSSID is filtered or 1 if not
1601  *
1602  * This function is used to filter out specific BSSIDs from scan reslts mainly
1603  * for testing purposes (SET bssid_filter ctrl_iface command).
1604  */
1605 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1606                                       const u8 *bssid)
1607 {
1608         size_t i;
1609
1610         if (wpa_s->bssid_filter == NULL)
1611                 return 1;
1612
1613         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1614                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1615                               ETH_ALEN) == 0)
1616                         return 1;
1617         }
1618
1619         return 0;
1620 }
1621
1622
1623 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1624                             struct wpa_scan_results *res)
1625 {
1626         size_t i, j;
1627
1628         if (wpa_s->bssid_filter == NULL)
1629                 return;
1630
1631         for (i = 0, j = 0; i < res->num; i++) {
1632                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1633                                                       res->res[i]->bssid)) {
1634                         res->res[j++] = res->res[i];
1635                 } else {
1636                         os_free(res->res[i]);
1637                         res->res[i] = NULL;
1638                 }
1639         }
1640
1641         if (res->num != j) {
1642                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1643                            (int) (res->num - j));
1644                 res->num = j;
1645         }
1646 }
1647
1648
1649 /**
1650  * wpa_supplicant_get_scan_results - Get scan results
1651  * @wpa_s: Pointer to wpa_supplicant data
1652  * @info: Information about what was scanned or %NULL if not available
1653  * @new_scan: Whether a new scan was performed
1654  * Returns: Scan results, %NULL on failure
1655  *
1656  * This function request the current scan results from the driver and updates
1657  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1658  * results with wpa_scan_results_free().
1659  */
1660 struct wpa_scan_results *
1661 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1662                                 struct scan_info *info, int new_scan)
1663 {
1664         struct wpa_scan_results *scan_res;
1665         size_t i;
1666         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1667
1668         scan_res = wpa_drv_get_scan_results2(wpa_s);
1669         if (scan_res == NULL) {
1670                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1671                 return NULL;
1672         }
1673         if (scan_res->fetch_time.sec == 0) {
1674                 /*
1675                  * Make sure we have a valid timestamp if the driver wrapper
1676                  * does not set this.
1677                  */
1678                 os_get_time(&scan_res->fetch_time);
1679         }
1680         filter_scan_res(wpa_s, scan_res);
1681
1682 #ifdef CONFIG_WPS
1683         if (wpas_wps_in_progress(wpa_s)) {
1684                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1685                         "provisioning rules");
1686                 compar = wpa_scan_result_wps_compar;
1687         }
1688 #endif /* CONFIG_WPS */
1689
1690         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1691               compar);
1692         dump_scan_res(scan_res);
1693
1694         wpa_bss_update_start(wpa_s);
1695         for (i = 0; i < scan_res->num; i++)
1696                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
1697                                         &scan_res->fetch_time);
1698         wpa_bss_update_end(wpa_s, info, new_scan);
1699
1700         return scan_res;
1701 }
1702
1703
1704 /**
1705  * wpa_supplicant_update_scan_results - Update scan results from the driver
1706  * @wpa_s: Pointer to wpa_supplicant data
1707  * Returns: 0 on success, -1 on failure
1708  *
1709  * This function updates the BSS table within wpa_supplicant based on the
1710  * currently available scan results from the driver without requesting a new
1711  * scan. This is used in cases where the driver indicates an association
1712  * (including roaming within ESS) and wpa_supplicant does not yet have the
1713  * needed information to complete the connection (e.g., to perform validation
1714  * steps in 4-way handshake).
1715  */
1716 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1717 {
1718         struct wpa_scan_results *scan_res;
1719         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1720         if (scan_res == NULL)
1721                 return -1;
1722         wpa_scan_results_free(scan_res);
1723
1724         return 0;
1725 }
1726
1727
1728 /**
1729  * scan_only_handler - Reports scan results
1730  */
1731 void scan_only_handler(struct wpa_supplicant *wpa_s,
1732                        struct wpa_scan_results *scan_res)
1733 {
1734         wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
1735         wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
1736         wpas_notify_scan_results(wpa_s);
1737         wpas_notify_scan_done(wpa_s, 1);
1738 }
1739
1740
1741 int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
1742 {
1743         return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
1744 }