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 "scan.h"
  25
  26
  27 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  28 {
  29         struct wpa_ssid *ssid;
  30         union wpa_event_data data;
  31
  32         ssid = wpa_supplicant_get_ssid(wpa_s);
  33         if (ssid == NULL)
  34                 return;
  35
  36         if (wpa_s->current_ssid == NULL) {
  37                 wpa_s->current_ssid = ssid;
  38                 if (wpa_s->current_ssid != NULL)
  39                         wpas_notify_network_changed(wpa_s);
  40         }
  41         wpa_supplicant_initiate_eapol(wpa_s);
  42         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
  43                 "network - generating associated event");
  44         os_memset(&data, 0, sizeof(data));
  45         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  46 }
  47
  48
  49 #ifdef CONFIG_WPS
  50 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
  51                            enum wps_request_type *req_type)
  52 {
  53         struct wpa_ssid *ssid;
  54         int wps = 0;
  55
  56         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
  57                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  58                         continue;
  59
  60                 wps = 1;
  61                 *req_type = wpas_wps_get_req_type(ssid);
  62                 if (!ssid->eap.phase1)
  63                         continue;
  64
  65                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  66                         return 2;
  67         }
  68
  69 #ifdef CONFIG_P2P
  70         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
  71             !wpa_s->conf->p2p_disabled) {
  72                 wpa_s->wps->dev.p2p = 1;
  73                 if (!wps) {
  74                         wps = 1;
  75                         *req_type = WPS_REQ_ENROLLEE_INFO;
  76                 }
  77         }
  78 #endif /* CONFIG_P2P */
  79
  80         return wps;
  81 }
  82 #endif /* CONFIG_WPS */
  83
  84
  85 /**
  86  * wpa_supplicant_enabled_networks - Check whether there are enabled networks
  87  * @wpa_s: Pointer to wpa_supplicant data
  88  * Returns: 0 if no networks are enabled, >0 if networks are enabled
  89  *
  90  * This function is used to figure out whether any networks (or Interworking
  91  * with enabled credentials and auto_interworking) are present in the current
  92  * configuration.
  93  */
  94 int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
  95 {
  96         struct wpa_ssid *ssid = wpa_s->conf->ssid;
  97         int count = 0, disabled = 0;
  98         while (ssid) {
  99                 if (!wpas_network_disabled(wpa_s, ssid))
 100                         count++;
 101                 else
 102                         disabled++;
 103                 ssid = ssid->next;
 104         }
 105         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 106             wpa_s->conf->auto_interworking)
 107                 count++;
 108         if (count == 0 && disabled > 0) {
 109                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
 110                         "networks)", disabled);
 111         }
 112         return count;
 113 }
 114
 115
 116 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
 117                                      struct wpa_ssid *ssid)
 118 {
 119         while (ssid) {
 120                 if (!wpas_network_disabled(wpa_s, ssid))
 121                         break;
 122                 ssid = ssid->next;
 123         }
 124
 125         /* ap_scan=2 mode - try to associate with each SSID. */
 126         if (ssid == NULL) {
 127                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 128                         "end of scan list - go back to beginning");
 129                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 130                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 131                 return;
 132         }
 133         if (ssid->next) {
 134                 /* Continue from the next SSID on the next attempt. */
 135                 wpa_s->prev_scan_ssid = ssid;
 136         } else {
 137                 /* Start from the beginning of the SSID list. */
 138                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 139         }
 140         wpa_supplicant_associate(wpa_s, NULL, ssid);
 141 }
 142
 143
 144 static int int_array_len(const int *a)
 145 {
 146         int i;
 147         for (i = 0; a && a[i]; i++)
 148                 ;
 149         return i;
 150 }
 151
 152
 153 static void int_array_concat(int **res, const int *a)
 154 {
 155         int reslen, alen, i;
 156         int *n;
 157
 158         reslen = int_array_len(*res);
 159         alen = int_array_len(a);
 160
 161         n = os_realloc_array(*res, reslen + alen + 1, sizeof(int));
 162         if (n == NULL) {
 163                 os_free(*res);
 164                 *res = NULL;
 165                 return;
 166         }
 167         for (i = 0; i <= alen; i++)
 168                 n[reslen + i] = a[i];
 169         *res = n;
 170 }
 171
 172
 173 static int freq_cmp(const void *a, const void *b)
 174 {
 175         int _a = *(int *) a;
 176         int _b = *(int *) b;
 177
 178         if (_a == 0)
 179                 return 1;
 180         if (_b == 0)
 181                 return -1;
 182         return _a - _b;
 183 }
 184
 185
 186 static void int_array_sort_unique(int *a)
 187 {
 188         int alen;
 189         int i, j;
 190
 191         if (a == NULL)
 192                 return;
 193
 194         alen = int_array_len(a);
 195         qsort(a, alen, sizeof(int), freq_cmp);
 196
 197         i = 0;
 198         j = 1;
 199         while (a[i] && a[j]) {
 200                 if (a[i] == a[j]) {
 201                         j++;
 202                         continue;
 203                 }
 204                 a[++i] = a[j++];
 205         }
 206         if (a[i])
 207                 i++;
 208         a[i] = 0;
 209 }
 210
 211
 212 /**
 213  * wpa_supplicant_trigger_scan - Request driver to start a scan
 214  * @wpa_s: Pointer to wpa_supplicant data
 215  * @params: Scan parameters
 216  * Returns: 0 on success, -1 on failure
 217  */
 218 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 219                                 struct wpa_driver_scan_params *params)
 220 {
 221         int ret;
 222
 223         wpa_supplicant_notify_scanning(wpa_s, 1);
 224
 225         ret = wpa_drv_scan(wpa_s, params);
 226         if (ret) {
 227                 wpa_supplicant_notify_scanning(wpa_s, 0);
 228                 wpas_notify_scan_done(wpa_s, 0);
 229         } else {
 230                 os_get_time(&wpa_s->scan_trigger_time);
 231                 wpa_s->scan_runs++;
 232                 wpa_s->normal_scans++;
 233         }
 234
 235         return ret;
 236 }
 237
 238
 239 static void
 240 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 241 {
 242         struct wpa_supplicant *wpa_s = eloop_ctx;
 243
 244         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 245
 246         if (wpa_supplicant_req_sched_scan(wpa_s))
 247                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 248 }
 249
 250
 251 static void
 252 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 253 {
 254         struct wpa_supplicant *wpa_s = eloop_ctx;
 255
 256         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 257
 258         wpa_s->sched_scan_timed_out = 1;
 259         wpa_supplicant_cancel_sched_scan(wpa_s);
 260 }
 261
 262
 263 static int
 264 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 265                                 struct wpa_driver_scan_params *params,
 266                                 int interval)
 267 {
 268         int ret;
 269
 270         wpa_supplicant_notify_scanning(wpa_s, 1);
 271         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 272         if (ret)
 273                 wpa_supplicant_notify_scanning(wpa_s, 0);
 274         else
 275                 wpa_s->sched_scanning = 1;
 276
 277         return ret;
 278 }
 279
 280
 281 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 282 {
 283         int ret;
 284
 285         ret = wpa_drv_stop_sched_scan(wpa_s);
 286         if (ret) {
 287                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 288                 /* TODO: what to do if stopping fails? */
 289                 return -1;
 290         }
 291
 292         return ret;
 293 }
 294
 295
 296 static struct wpa_driver_scan_filter *
 297 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 298 {
 299         struct wpa_driver_scan_filter *ssids;
 300         struct wpa_ssid *ssid;
 301         size_t count;
 302
 303         *num_ssids = 0;
 304         if (!conf->filter_ssids)
 305                 return NULL;
 306
 307         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 308                 if (ssid->ssid && ssid->ssid_len)
 309                         count++;
 310         }
 311         if (count == 0)
 312                 return NULL;
 313         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 314         if (ssids == NULL)
 315                 return NULL;
 316
 317         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 318                 if (!ssid->ssid || !ssid->ssid_len)
 319                         continue;
 320                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 321                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 322                 (*num_ssids)++;
 323         }
 324
 325         return ssids;
 326 }
 327
 328
 329 static void wpa_supplicant_optimize_freqs(
 330         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 331 {
 332 #ifdef CONFIG_P2P
 333         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 334             wpa_s->go_params) {
 335                 /* Optimize provisioning state scan based on GO information */
 336                 if (wpa_s->p2p_in_provisioning < 5 &&
 337                     wpa_s->go_params->freq > 0) {
 338                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 339                                 "preferred frequency %d MHz",
 340                                 wpa_s->go_params->freq);
 341                         params->freqs = os_zalloc(2 * sizeof(int));
 342                         if (params->freqs)
 343                                 params->freqs[0] = wpa_s->go_params->freq;
 344                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 345                            wpa_s->go_params->freq_list[0]) {
 346                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 347                                 "channels");
 348                         int_array_concat(&params->freqs,
 349                                          wpa_s->go_params->freq_list);
 350                         if (params->freqs)
 351                                 int_array_sort_unique(params->freqs);
 352                 }
 353                 wpa_s->p2p_in_provisioning++;
 354         }
 355 #endif /* CONFIG_P2P */
 356
 357 #ifdef CONFIG_WPS
 358         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 359                 /*
 360                  * Optimize post-provisioning scan based on channel used
 361                  * during provisioning.
 362                  */
 363                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 364                         "that was used during provisioning", wpa_s->wps_freq);
 365                 params->freqs = os_zalloc(2 * sizeof(int));
 366                 if (params->freqs)
 367                         params->freqs[0] = wpa_s->wps_freq;
 368                 wpa_s->after_wps--;
 369         }
 370
 371         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 372         {
 373                 /* Optimize provisioning scan based on already known channel */
 374                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 375                         wpa_s->wps_freq);
 376                 params->freqs = os_zalloc(2 * sizeof(int));
 377                 if (params->freqs)
 378                         params->freqs[0] = wpa_s->wps_freq;
 379                 wpa_s->known_wps_freq = 0; /* only do this once */
 380         }
 381 #endif /* CONFIG_WPS */
 382 }
 383
 384
 385 #ifdef CONFIG_INTERWORKING
 386 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 387                                            struct wpabuf *buf)
 388 {
 389         if (wpa_s->conf->interworking == 0)
 390                 return;
 391
 392         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 393         wpabuf_put_u8(buf, 4);
 394         wpabuf_put_u8(buf, 0x00);
 395         wpabuf_put_u8(buf, 0x00);
 396         wpabuf_put_u8(buf, 0x00);
 397         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 398
 399         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 400         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 401                       1 + ETH_ALEN);
 402         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 403         /* No Venue Info */
 404         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 405                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 406 }
 407 #endif /* CONFIG_INTERWORKING */
 408
 409
 410 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
 411 {
 412         struct wpabuf *extra_ie = NULL;
 413 #ifdef CONFIG_WPS
 414         int wps = 0;
 415         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 416 #endif /* CONFIG_WPS */
 417
 418 #ifdef CONFIG_INTERWORKING
 419         if (wpa_s->conf->interworking &&
 420             wpabuf_resize(&extra_ie, 100) == 0)
 421                 wpas_add_interworking_elements(wpa_s, extra_ie);
 422 #endif /* CONFIG_INTERWORKING */
 423
 424 #ifdef CONFIG_WPS
 425         wps = wpas_wps_in_use(wpa_s, &req_type);
 426
 427         if (wps) {
 428                 struct wpabuf *wps_ie;
 429                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
 430                                                 DEV_PW_DEFAULT,
 431                                                 &wpa_s->wps->dev,
 432                                                 wpa_s->wps->uuid, req_type,
 433                                                 0, NULL);
 434                 if (wps_ie) {
 435                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 436                                 wpabuf_put_buf(extra_ie, wps_ie);
 437                         wpabuf_free(wps_ie);
 438                 }
 439         }
 440
 441 #ifdef CONFIG_P2P
 442         if (wps) {
 443                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 444                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 445                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 446         }
 447 #endif /* CONFIG_P2P */
 448
 449 #endif /* CONFIG_WPS */
 450
 451 #ifdef CONFIG_HS20
 452         if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
 453                 wpas_hs20_add_indication(extra_ie);
 454 #endif /* CONFIG_HS20 */
 455
 456         return extra_ie;
 457 }
 458
 459
 460 #ifdef CONFIG_P2P
 461
 462 /*
 463  * Check whether there are any enabled networks or credentials that could be
 464  * used for a non-P2P connection.
 465  */
 466 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
 467 {
 468         struct wpa_ssid *ssid;
 469
 470         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 471                 if (wpas_network_disabled(wpa_s, ssid))
 472                         continue;
 473                 if (!ssid->p2p_group)
 474                         return 1;
 475         }
 476
 477         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 478             wpa_s->conf->auto_interworking)
 479                 return 1;
 480
 481         return 0;
 482 }
 483
 484 #endif /* CONFIG_P2P */
 485
 486 /*
 487  * Find the operating frequency of any other virtual interface that is using
 488  * the same radio concurrently.
 489  */
 490 static int shared_vif_oper_freq(struct wpa_supplicant *wpa_s)
 491 {
 492         const char *rn, *rn2;
 493         struct wpa_supplicant *ifs;
 494         u8 bssid[ETH_ALEN];
 495
 496         if (!wpa_s->driver->get_radio_name)
 497                 return -1;
 498
 499         rn = wpa_s->driver->get_radio_name(wpa_s->drv_priv);
 500         if (rn == NULL || rn[0] == '\0')
 501                 return -1;
 502
 503         for (ifs = wpa_s->global->ifaces; ifs; ifs = ifs->next) {
 504                 if (ifs == wpa_s || !ifs->driver->get_radio_name)
 505                         continue;
 506
 507                 rn2 = ifs->driver->get_radio_name(ifs->drv_priv);
 508                 if (!rn2 || os_strcmp(rn, rn2) != 0)
 509                         continue;
 510
 511                 if (ifs->current_ssid == NULL || ifs->assoc_freq == 0)
 512                         continue;
 513
 514                 if (ifs->current_ssid->mode == WPAS_MODE_AP ||
 515                     ifs->current_ssid->mode == WPAS_MODE_P2P_GO)
 516                         return ifs->current_ssid->frequency;
 517                 if (wpa_drv_get_bssid(ifs, bssid) == 0)
 518                         return ifs->assoc_freq;
 519         }
 520
 521         return 0;
 522 }
 523
 524
 525 static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
 526                                           u16 num_modes,
 527                                           enum hostapd_hw_mode mode)
 528 {
 529         u16 i;
 530
 531         for (i = 0; i < num_modes; i++) {
 532                 if (modes[i].mode == mode)
 533                         return &modes[i];
 534         }
 535
 536         return NULL;
 537 }
 538
 539
 540 static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
 541                                         enum hostapd_hw_mode band,
 542                                         struct wpa_driver_scan_params *params)
 543 {
 544         /* Include only supported channels for the specified band */
 545         struct hostapd_hw_modes *mode;
 546         int count, i;
 547
 548         mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
 549         if (mode == NULL) {
 550                 /* No channels supported in this band - use empty list */
 551                 params->freqs = os_zalloc(sizeof(int));
 552                 return;
 553         }
 554
 555         params->freqs = os_zalloc((mode->num_channels + 1) * sizeof(int));
 556         if (params->freqs == NULL)
 557                 return;
 558         for (count = 0, i = 0; i < mode->num_channels; i++) {
 559                 if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
 560                         continue;
 561                 params->freqs[count++] = mode->channels[i].freq;
 562         }
 563 }
 564
 565
 566 static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
 567                                    struct wpa_driver_scan_params *params)
 568 {
 569         if (wpa_s->hw.modes == NULL)
 570                 return; /* unknown what channels the driver supports */
 571         if (params->freqs)
 572                 return; /* already using a limited channel set */
 573         if (wpa_s->setband == WPA_SETBAND_5G)
 574                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
 575                                             params);
 576         else if (wpa_s->setband == WPA_SETBAND_2G)
 577                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
 578                                             params);
 579 }
 580
 581
 582 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 583 {
 584         struct wpa_supplicant *wpa_s = eloop_ctx;
 585         struct wpa_ssid *ssid;
 586         enum scan_req_type scan_req = NORMAL_SCAN_REQ;
 587         int ret;
 588         struct wpabuf *extra_ie = NULL;
 589         struct wpa_driver_scan_params params;
 590         struct wpa_driver_scan_params *scan_params;
 591         size_t max_ssids;
 592         enum wpa_states prev_state;
 593
 594         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 595                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 596                 wpas_p2p_continue_after_scan(wpa_s);
 597                 return;
 598         }
 599
 600         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
 601                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
 602                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 603                 wpas_p2p_continue_after_scan(wpa_s);
 604                 return;
 605         }
 606
 607         if (!wpa_supplicant_enabled_networks(wpa_s) &&
 608             wpa_s->scan_req == NORMAL_SCAN_REQ) {
 609                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 610                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 611                 wpas_p2p_continue_after_scan(wpa_s);
 612                 return;
 613         }
 614
 615         if (wpa_s->conf->ap_scan != 0 &&
 616             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 617                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 618                         "overriding ap_scan configuration");
 619                 wpa_s->conf->ap_scan = 0;
 620                 wpas_notify_ap_scan_changed(wpa_s);
 621         }
 622
 623         if (wpa_s->conf->ap_scan == 0) {
 624                 wpa_supplicant_gen_assoc_event(wpa_s);
 625                 return;
 626         }
 627
 628 #ifdef CONFIG_P2P
 629         if (wpas_p2p_in_progress(wpa_s) || wpas_wpa_is_in_progress(wpa_s)) {
 630                 if (wpa_s->sta_scan_pending &&
 631                     wpas_p2p_in_progress(wpa_s) == 2 &&
 632                     wpa_s->global->p2p_cb_on_scan_complete) {
 633                         wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
 634                                 "mode scan during P2P search");
 635                 } else {
 636                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 637                                 "while P2P operation is in progress");
 638                         wpa_s->sta_scan_pending = 1;
 639                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 640                         return;
 641                 }
 642         }
 643 #endif /* CONFIG_P2P */
 644
 645         if (wpa_s->conf->ap_scan == 2)
 646                 max_ssids = 1;
 647         else {
 648                 max_ssids = wpa_s->max_scan_ssids;
 649                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 650                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 651         }
 652
 653         scan_req = wpa_s->scan_req;
 654         wpa_s->scan_req = NORMAL_SCAN_REQ;
 655
 656         os_memset(&params, 0, sizeof(params));
 657
 658         prev_state = wpa_s->wpa_state;
 659         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 660             wpa_s->wpa_state == WPA_INACTIVE)
 661                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 662
 663         /*
 664          * If autoscan has set its own scanning parameters
 665          */
 666         if (wpa_s->autoscan_params != NULL) {
 667                 scan_params = wpa_s->autoscan_params;
 668                 goto scan;
 669         }
 670
 671         if (scan_req != MANUAL_SCAN_REQ && wpa_s->connect_without_scan) {
 672                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 673                         if (ssid == wpa_s->connect_without_scan)
 674                                 break;
 675                 }
 676                 wpa_s->connect_without_scan = NULL;
 677                 if (ssid) {
 678                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 679                                    "without scan step");
 680                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 681                         return;
 682                 }
 683         }
 684
 685 #ifdef CONFIG_P2P
 686         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
 687             wpa_s->go_params) {
 688                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during "
 689                            "P2P group formation");
 690                 params.ssids[0].ssid = wpa_s->go_params->ssid;
 691                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
 692                 params.num_ssids = 1;
 693                 goto ssid_list_set;
 694         }
 695 #endif /* CONFIG_P2P */
 696
 697         /* Find the starting point from which to continue scanning */
 698         ssid = wpa_s->conf->ssid;
 699         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 700                 while (ssid) {
 701                         if (ssid == wpa_s->prev_scan_ssid) {
 702                                 ssid = ssid->next;
 703                                 break;
 704                         }
 705                         ssid = ssid->next;
 706                 }
 707         }
 708
 709         if (scan_req != MANUAL_SCAN_REQ && wpa_s->conf->ap_scan == 2) {
 710                 wpa_s->connect_without_scan = NULL;
 711                 wpa_s->prev_scan_wildcard = 0;
 712                 wpa_supplicant_assoc_try(wpa_s, ssid);
 713                 return;
 714         } else if (wpa_s->conf->ap_scan == 2) {
 715                 /*
 716                  * User-initiated scan request in ap_scan == 2; scan with
 717                  * wildcard SSID.
 718                  */
 719                 ssid = NULL;
 720         } else {
 721                 struct wpa_ssid *start = ssid, *tssid;
 722                 int freqs_set = 0;
 723                 if (ssid == NULL && max_ssids > 1)
 724                         ssid = wpa_s->conf->ssid;
 725                 while (ssid) {
 726                         if (!wpas_network_disabled(wpa_s, ssid) &&
 727                             ssid->scan_ssid) {
 728                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 729                                                   ssid->ssid, ssid->ssid_len);
 730                                 params.ssids[params.num_ssids].ssid =
 731                                         ssid->ssid;
 732                                 params.ssids[params.num_ssids].ssid_len =
 733                                         ssid->ssid_len;
 734                                 params.num_ssids++;
 735                                 if (params.num_ssids + 1 >= max_ssids)
 736                                         break;
 737                         }
 738                         ssid = ssid->next;
 739                         if (ssid == start)
 740                                 break;
 741                         if (ssid == NULL && max_ssids > 1 &&
 742                             start != wpa_s->conf->ssid)
 743                                 ssid = wpa_s->conf->ssid;
 744                 }
 745
 746                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 747                         if (wpas_network_disabled(wpa_s, tssid))
 748                                 continue;
 749                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 750                                 int_array_concat(&params.freqs,
 751                                                  tssid->scan_freq);
 752                         } else {
 753                                 os_free(params.freqs);
 754                                 params.freqs = NULL;
 755                         }
 756                         freqs_set = 1;
 757                 }
 758                 int_array_sort_unique(params.freqs);
 759         }
 760
 761         if (ssid && max_ssids == 1) {
 762                 /*
 763                  * If the driver is limited to 1 SSID at a time interleave
 764                  * wildcard SSID scans with specific SSID scans to avoid
 765                  * waiting a long time for a wildcard scan.
 766                  */
 767                 if (!wpa_s->prev_scan_wildcard) {
 768                         params.ssids[0].ssid = NULL;
 769                         params.ssids[0].ssid_len = 0;
 770                         wpa_s->prev_scan_wildcard = 1;
 771                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 772                                 "wildcard SSID (Interleave with specific)");
 773                 } else {
 774                         wpa_s->prev_scan_ssid = ssid;
 775                         wpa_s->prev_scan_wildcard = 0;
 776                         wpa_dbg(wpa_s, MSG_DEBUG,
 777                                 "Starting AP scan for specific SSID: %s",
 778                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 779                 }
 780         } else if (ssid) {
 781                 /* max_ssids > 1 */
 782
 783                 wpa_s->prev_scan_ssid = ssid;
 784                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 785                         "the scan request");
 786                 params.num_ssids++;
 787         } else {
 788                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 789                 params.num_ssids++;
 790                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 791                         "SSID");
 792         }
 793 #ifdef CONFIG_P2P
 794 ssid_list_set:
 795 #endif /* CONFIG_P2P */
 796
 797         wpa_supplicant_optimize_freqs(wpa_s, &params);
 798         extra_ie = wpa_supplicant_extra_ies(wpa_s);
 799
 800         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 801                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 802                         "generated frequency list");
 803                 params.freqs = wpa_s->next_scan_freqs;
 804         } else
 805                 os_free(wpa_s->next_scan_freqs);
 806         wpa_s->next_scan_freqs = NULL;
 807         wpa_setband_scan_freqs(wpa_s, &params);
 808
 809         /* See if user specified frequencies. If so, scan only those. */
 810         if (wpa_s->conf->freq_list && !params.freqs) {
 811                 wpa_dbg(wpa_s, MSG_DEBUG,
 812                         "Optimize scan based on conf->freq_list");
 813                 int_array_concat(&params.freqs, wpa_s->conf->freq_list);
 814         }
 815
 816         /* Use current associated channel? */
 817         if (wpa_s->conf->scan_cur_freq && !params.freqs) {
 818                 int freq = shared_vif_oper_freq(wpa_s);
 819                 if (freq > 0) {
 820                         wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current "
 821                                 "operating channel (%d MHz) since "
 822                                 "scan_cur_freq is enabled", freq);
 823                         params.freqs = os_zalloc(sizeof(int) * 2);
 824                         if (params.freqs)
 825                                 params.freqs[0] = freq;
 826                 }
 827         }
 828
 829         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 830                 wpa_s->conf, &params.num_filter_ssids);
 831         if (extra_ie) {
 832                 params.extra_ies = wpabuf_head(extra_ie);
 833                 params.extra_ies_len = wpabuf_len(extra_ie);
 834         }
 835
 836 #ifdef CONFIG_P2P
 837         if (wpa_s->p2p_in_provisioning ||
 838             (wpa_s->show_group_started && wpa_s->go_params)) {
 839                 /*
 840                  * The interface may not yet be in P2P mode, so we have to
 841                  * explicitly request P2P probe to disable CCK rates.
 842                  */
 843                 params.p2p_probe = 1;
 844         }
 845 #endif /* CONFIG_P2P */
 846
 847         scan_params = &params;
 848
 849 scan:
 850 #ifdef CONFIG_P2P
 851         /*
 852          * If the driver does not support multi-channel concurrency and a
 853          * virtual interface that shares the same radio with the wpa_s interface
 854          * is operating there may not be need to scan other channels apart from
 855          * the current operating channel on the other virtual interface. Filter
 856          * out other channels in case we are trying to find a connection for a
 857          * station interface when we are not configured to prefer station
 858          * connection and a concurrent operation is already in process.
 859          */
 860         if (wpa_s->scan_for_connection && scan_req == NORMAL_SCAN_REQ &&
 861             !scan_params->freqs && !params.freqs &&
 862             wpas_is_p2p_prioritized(wpa_s) &&
 863             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_MULTI_CHANNEL_CONCURRENT) &&
 864             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
 865             non_p2p_network_enabled(wpa_s)) {
 866                 int freq = shared_vif_oper_freq(wpa_s);
 867                 if (freq > 0) {
 868                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only the current "
 869                                 "operating channel (%d MHz) since driver does "
 870                                 "not support multi-channel concurrency", freq);
 871                         params.freqs = os_zalloc(sizeof(int) * 2);
 872                         if (params.freqs)
 873                                 params.freqs[0] = freq;
 874                         scan_params->freqs = params.freqs;
 875                 }
 876         }
 877 #endif /* CONFIG_P2P */
 878
 879         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
 880
 881         wpabuf_free(extra_ie);
 882         os_free(params.freqs);
 883         os_free(params.filter_ssids);
 884
 885         if (ret) {
 886                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 887                 if (prev_state != wpa_s->wpa_state)
 888                         wpa_supplicant_set_state(wpa_s, prev_state);
 889                 /* Restore scan_req since we will try to scan again */
 890                 wpa_s->scan_req = scan_req;
 891                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 892         } else {
 893                 wpa_s->scan_for_connection = 0;
 894         }
 895 }
 896
 897
 898 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 899 {
 900         struct os_time remaining, new_int;
 901         int cancelled;
 902
 903         cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
 904                                              &remaining);
 905
 906         new_int.sec = sec;
 907         new_int.usec = 0;
 908         if (cancelled && os_time_before(&remaining, &new_int)) {
 909                 new_int.sec = remaining.sec;
 910                 new_int.usec = remaining.usec;
 911         }
 912
 913         eloop_register_timeout(new_int.sec, new_int.usec, wpa_supplicant_scan,
 914                                wpa_s, NULL);
 915         wpa_s->scan_interval = sec;
 916 }
 917
 918
 919 /**
 920  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 921  * @wpa_s: Pointer to wpa_supplicant data
 922  * @sec: Number of seconds after which to scan
 923  * @usec: Number of microseconds after which to scan
 924  *
 925  * This function is used to schedule a scan for neighboring access points after
 926  * the specified time.
 927  */
 928 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 929 {
 930         /* If there's at least one network that should be specifically scanned
 931          * then don't cancel the scan and reschedule.  Some drivers do
 932          * background scanning which generates frequent scan results, and that
 933          * causes the specific SSID scan to get continually pushed back and
 934          * never happen, which causes hidden APs to never get probe-scanned.
 935          */
 936         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 937             wpa_s->conf->ap_scan == 1) {
 938                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 939
 940                 while (ssid) {
 941                         if (!wpas_network_disabled(wpa_s, ssid) &&
 942                             ssid->scan_ssid)
 943                                 break;
 944                         ssid = ssid->next;
 945                 }
 946                 if (ssid) {
 947                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 948                                 "ensure that specific SSID scans occur");
 949                         return;
 950                 }
 951         }
 952
 953         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 954                 sec, usec);
 955         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 956         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 957 }
 958
 959
 960 /**
 961  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 962  * @wpa_s: Pointer to wpa_supplicant data
 963  * @sec: Number of seconds after which to scan
 964  * @usec: Number of microseconds after which to scan
 965  * Returns: 0 on success or -1 otherwise
 966  *
 967  * This function is used to schedule periodic scans for neighboring
 968  * access points after the specified time.
 969  */
 970 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 971                                       int sec, int usec)
 972 {
 973         if (!wpa_s->sched_scan_supported)
 974                 return -1;
 975
 976         eloop_register_timeout(sec, usec,
 977                                wpa_supplicant_delayed_sched_scan_timeout,
 978                                wpa_s, NULL);
 979
 980         return 0;
 981 }
 982
 983
 984 /**
 985  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 986  * @wpa_s: Pointer to wpa_supplicant data
 987  * Returns: 0 is sched_scan was started or -1 otherwise
 988  *
 989  * This function is used to schedule periodic scans for neighboring
 990  * access points repeating the scan continuously.
 991  */
 992 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 993 {
 994         struct wpa_driver_scan_params params;
 995         struct wpa_driver_scan_params *scan_params;
 996         enum wpa_states prev_state;
 997         struct wpa_ssid *ssid = NULL;
 998         struct wpabuf *extra_ie = NULL;
 999         int ret;
1000         unsigned int max_sched_scan_ssids;
1001         int wildcard = 0;
1002         int need_ssids;
1003
1004         if (!wpa_s->sched_scan_supported)
1005                 return -1;
1006
1007         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
1008                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
1009         else
1010                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
1011         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
1012                 return -1;
1013
1014         if (wpa_s->sched_scanning) {
1015                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
1016                 return 0;
1017         }
1018
1019         need_ssids = 0;
1020         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
1021                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
1022                         /* Use wildcard SSID to find this network */
1023                         wildcard = 1;
1024                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
1025                            ssid->ssid_len)
1026                         need_ssids++;
1027
1028 #ifdef CONFIG_WPS
1029                 if (!wpas_network_disabled(wpa_s, ssid) &&
1030                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
1031                         /*
1032                          * Normal scan is more reliable and faster for WPS
1033                          * operations and since these are for short periods of
1034                          * time, the benefit of trying to use sched_scan would
1035                          * be limited.
1036                          */
1037                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1038                                 "sched_scan for WPS");
1039                         return -1;
1040                 }
1041 #endif /* CONFIG_WPS */
1042         }
1043         if (wildcard)
1044                 need_ssids++;
1045
1046         if (wpa_s->normal_scans < 3 &&
1047             (need_ssids <= wpa_s->max_scan_ssids ||
1048              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
1049                 /*
1050                  * When normal scan can speed up operations, use that for the
1051                  * first operations before starting the sched_scan to allow
1052                  * user space sleep more. We do this only if the normal scan
1053                  * has functionality that is suitable for this or if the
1054                  * sched_scan does not have better support for multiple SSIDs.
1055                  */
1056                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1057                         "sched_scan for initial scans (normal_scans=%d)",
1058                         wpa_s->normal_scans);
1059                 return -1;
1060         }
1061
1062         os_memset(&params, 0, sizeof(params));
1063
1064         /* If we can't allocate space for the filters, we just don't filter */
1065         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
1066                                         sizeof(struct wpa_driver_scan_filter));
1067
1068         prev_state = wpa_s->wpa_state;
1069         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
1070             wpa_s->wpa_state == WPA_INACTIVE)
1071                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
1072
1073         if (wpa_s->autoscan_params != NULL) {
1074                 scan_params = wpa_s->autoscan_params;
1075                 goto scan;
1076         }
1077
1078         /* Find the starting point from which to continue scanning */
1079         ssid = wpa_s->conf->ssid;
1080         if (wpa_s->prev_sched_ssid) {
1081                 while (ssid) {
1082                         if (ssid == wpa_s->prev_sched_ssid) {
1083                                 ssid = ssid->next;
1084                                 break;
1085                         }
1086                         ssid = ssid->next;
1087                 }
1088         }
1089
1090         if (!ssid || !wpa_s->prev_sched_ssid) {
1091                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
1092                 if (wpa_s->conf->sched_scan_interval)
1093                         wpa_s->sched_scan_interval =
1094                                 wpa_s->conf->sched_scan_interval;
1095                 if (wpa_s->sched_scan_interval == 0)
1096                         wpa_s->sched_scan_interval = 10;
1097                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1098                 wpa_s->first_sched_scan = 1;
1099                 ssid = wpa_s->conf->ssid;
1100                 wpa_s->prev_sched_ssid = ssid;
1101         }
1102
1103         if (wildcard) {
1104                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1105                 params.num_ssids++;
1106         }
1107
1108         while (ssid) {
1109                 if (wpas_network_disabled(wpa_s, ssid))
1110                         goto next;
1111
1112                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
1113                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1114                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1115                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1116                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1117                                   ssid->ssid, ssid->ssid_len);
1118                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1119                                 ssid->ssid_len;
1120                         params.num_filter_ssids++;
1121                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1122                 {
1123                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1124                                 "filter for sched_scan - drop filter");
1125                         os_free(params.filter_ssids);
1126                         params.filter_ssids = NULL;
1127                         params.num_filter_ssids = 0;
1128                 }
1129
1130                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1131                         if (params.num_ssids == max_sched_scan_ssids)
1132                                 break; /* only room for broadcast SSID */
1133                         wpa_dbg(wpa_s, MSG_DEBUG,
1134                                 "add to active scan ssid: %s",
1135                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1136                         params.ssids[params.num_ssids].ssid =
1137                                 ssid->ssid;
1138                         params.ssids[params.num_ssids].ssid_len =
1139                                 ssid->ssid_len;
1140                         params.num_ssids++;
1141                         if (params.num_ssids >= max_sched_scan_ssids) {
1142                                 wpa_s->prev_sched_ssid = ssid;
1143                                 do {
1144                                         ssid = ssid->next;
1145                                 } while (ssid &&
1146                                          (wpas_network_disabled(wpa_s, ssid) ||
1147                                           !ssid->scan_ssid));
1148                                 break;
1149                         }
1150                 }
1151
1152         next:
1153                 wpa_s->prev_sched_ssid = ssid;
1154                 ssid = ssid->next;
1155         }
1156
1157         if (params.num_filter_ssids == 0) {
1158                 os_free(params.filter_ssids);
1159                 params.filter_ssids = NULL;
1160         }
1161
1162         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1163         if (extra_ie) {
1164                 params.extra_ies = wpabuf_head(extra_ie);
1165                 params.extra_ies_len = wpabuf_len(extra_ie);
1166         }
1167
1168         scan_params = &params;
1169
1170 scan:
1171         if (ssid || !wpa_s->first_sched_scan) {
1172                 wpa_dbg(wpa_s, MSG_DEBUG,
1173                         "Starting sched scan: interval %d timeout %d",
1174                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1175         } else {
1176                 wpa_dbg(wpa_s, MSG_DEBUG,
1177                         "Starting sched scan: interval %d (no timeout)",
1178                         wpa_s->sched_scan_interval);
1179         }
1180
1181         wpa_setband_scan_freqs(wpa_s, scan_params);
1182
1183         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1184                                               wpa_s->sched_scan_interval);
1185         wpabuf_free(extra_ie);
1186         os_free(params.filter_ssids);
1187         if (ret) {
1188                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1189                 if (prev_state != wpa_s->wpa_state)
1190                         wpa_supplicant_set_state(wpa_s, prev_state);
1191                 return ret;
1192         }
1193
1194         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1195         if (ssid || !wpa_s->first_sched_scan) {
1196                 wpa_s->sched_scan_timed_out = 0;
1197                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1198                                        wpa_supplicant_sched_scan_timeout,
1199                                        wpa_s, NULL);
1200                 wpa_s->first_sched_scan = 0;
1201                 wpa_s->sched_scan_timeout /= 2;
1202                 wpa_s->sched_scan_interval *= 2;
1203                 if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
1204                         wpa_s->sched_scan_interval = 10;
1205                         wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1206                 }
1207         }
1208
1209         /* If there is no more ssids, start next time from the beginning */
1210         if (!ssid)
1211                 wpa_s->prev_sched_ssid = NULL;
1212
1213         return 0;
1214 }
1215
1216
1217 /**
1218  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1219  * @wpa_s: Pointer to wpa_supplicant data
1220  *
1221  * This function is used to cancel a scan request scheduled with
1222  * wpa_supplicant_req_scan().
1223  */
1224 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1225 {
1226         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1227         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1228         wpas_p2p_continue_after_scan(wpa_s);
1229 }
1230
1231
1232 /**
1233  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1234  * @wpa_s: Pointer to wpa_supplicant data
1235  *
1236  * This function is used to stop a periodic scheduled scan.
1237  */
1238 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1239 {
1240         if (!wpa_s->sched_scanning)
1241                 return;
1242
1243         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1244         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1245         wpa_supplicant_stop_sched_scan(wpa_s);
1246 }
1247
1248
1249 /**
1250  * wpa_supplicant_notify_scanning - Indicate possible scan state change
1251  * @wpa_s: Pointer to wpa_supplicant data
1252  * @scanning: Whether scanning is currently in progress
1253  *
1254  * This function is to generate scanning notifycations. It is called whenever
1255  * there may have been a change in scanning (scan started, completed, stopped).
1256  * wpas_notify_scanning() is called whenever the scanning state changed from the
1257  * previously notified state.
1258  */
1259 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1260                                     int scanning)
1261 {
1262         if (wpa_s->scanning != scanning) {
1263                 wpa_s->scanning = scanning;
1264                 wpas_notify_scanning(wpa_s);
1265         }
1266 }
1267
1268
1269 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1270 {
1271         int rate = 0;
1272         const u8 *ie;
1273         int i;
1274
1275         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1276         for (i = 0; ie && i < ie[1]; i++) {
1277                 if ((ie[i + 2] & 0x7f) > rate)
1278                         rate = ie[i + 2] & 0x7f;
1279         }
1280
1281         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1282         for (i = 0; ie && i < ie[1]; i++) {
1283                 if ((ie[i + 2] & 0x7f) > rate)
1284                         rate = ie[i + 2] & 0x7f;
1285         }
1286
1287         return rate;
1288 }
1289
1290
1291 /**
1292  * wpa_scan_get_ie - Fetch a specified information element from a scan result
1293  * @res: Scan result entry
1294  * @ie: Information element identitifier (WLAN_EID_*)
1295  * Returns: Pointer to the information element (id field) or %NULL if not found
1296  *
1297  * This function returns the first matching information element in the scan
1298  * result.
1299  */
1300 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1301 {
1302         const u8 *end, *pos;
1303
1304         pos = (const u8 *) (res + 1);
1305         end = pos + res->ie_len;
1306
1307         while (pos + 1 < end) {
1308                 if (pos + 2 + pos[1] > end)
1309                         break;
1310                 if (pos[0] == ie)
1311                         return pos;
1312                 pos += 2 + pos[1];
1313         }
1314
1315         return NULL;
1316 }
1317
1318
1319 /**
1320  * wpa_scan_get_vendor_ie - Fetch vendor information element from a scan result
1321  * @res: Scan result entry
1322  * @vendor_type: Vendor type (four octets starting the IE payload)
1323  * Returns: Pointer to the information element (id field) or %NULL if not found
1324  *
1325  * This function returns the first matching information element in the scan
1326  * result.
1327  */
1328 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1329                                   u32 vendor_type)
1330 {
1331         const u8 *end, *pos;
1332
1333         pos = (const u8 *) (res + 1);
1334         end = pos + res->ie_len;
1335
1336         while (pos + 1 < end) {
1337                 if (pos + 2 + pos[1] > end)
1338                         break;
1339                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1340                     vendor_type == WPA_GET_BE32(&pos[2]))
1341                         return pos;
1342                 pos += 2 + pos[1];
1343         }
1344
1345         return NULL;
1346 }
1347
1348
1349 /**
1350  * wpa_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
1351  * @res: Scan result entry
1352  * @vendor_type: Vendor type (four octets starting the IE payload)
1353  * Returns: Pointer to the information element payload or %NULL if not found
1354  *
1355  * This function returns concatenated payload of possibly fragmented vendor
1356  * specific information elements in the scan result. The caller is responsible
1357  * for freeing the returned buffer.
1358  */
1359 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1360                                              u32 vendor_type)
1361 {
1362         struct wpabuf *buf;
1363         const u8 *end, *pos;
1364
1365         buf = wpabuf_alloc(res->ie_len);
1366         if (buf == NULL)
1367                 return NULL;
1368
1369         pos = (const u8 *) (res + 1);
1370         end = pos + res->ie_len;
1371
1372         while (pos + 1 < end) {
1373                 if (pos + 2 + pos[1] > end)
1374                         break;
1375                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1376                     vendor_type == WPA_GET_BE32(&pos[2]))
1377                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1378                 pos += 2 + pos[1];
1379         }
1380
1381         if (wpabuf_len(buf) == 0) {
1382                 wpabuf_free(buf);
1383                 buf = NULL;
1384         }
1385
1386         return buf;
1387 }
1388
1389
1390 /*
1391  * Channels with a great SNR can operate at full rate. What is a great SNR?
1392  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1393  * rule of thumb is that any SNR above 20 is good." This one
1394  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1395  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1396  * conservative value.
1397  */
1398 #define GREAT_SNR 30
1399
1400 /* Compare function for sorting scan results. Return >0 if @b is considered
1401  * better. */
1402 static int wpa_scan_result_compar(const void *a, const void *b)
1403 {
1404 #define IS_5GHZ(n) (n > 4000)
1405 #define MIN(a,b) a < b ? a : b
1406         struct wpa_scan_res **_wa = (void *) a;
1407         struct wpa_scan_res **_wb = (void *) b;
1408         struct wpa_scan_res *wa = *_wa;
1409         struct wpa_scan_res *wb = *_wb;
1410         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1411         int snr_a, snr_b;
1412
1413         /* WPA/WPA2 support preferred */
1414         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1415                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1416         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1417                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1418
1419         if (wpa_b && !wpa_a)
1420                 return 1;
1421         if (!wpa_b && wpa_a)
1422                 return -1;
1423
1424         /* privacy support preferred */
1425         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1426             (wb->caps & IEEE80211_CAP_PRIVACY))
1427                 return 1;
1428         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1429             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1430                 return -1;
1431
1432         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1433             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1434                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1435                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1436         } else {
1437                 /* Not suitable information to calculate SNR, so use level */
1438                 snr_a = wa->level;
1439                 snr_b = wb->level;
1440         }
1441
1442         /* best/max rate preferred if SNR close enough */
1443         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1444             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1445                 maxrate_a = wpa_scan_get_max_rate(wa);
1446                 maxrate_b = wpa_scan_get_max_rate(wb);
1447                 if (maxrate_a != maxrate_b)
1448                         return maxrate_b - maxrate_a;
1449                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1450                         return IS_5GHZ(wa->freq) ? -1 : 1;
1451         }
1452
1453         /* use freq for channel preference */
1454
1455         /* all things being equal, use SNR; if SNRs are
1456          * identical, use quality values since some drivers may only report
1457          * that value and leave the signal level zero */
1458         if (snr_b == snr_a)
1459                 return wb->qual - wa->qual;
1460         return snr_b - snr_a;
1461 #undef MIN
1462 #undef IS_5GHZ
1463 }
1464
1465
1466 #ifdef CONFIG_WPS
1467 /* Compare function for sorting scan results when searching a WPS AP for
1468  * provisioning. Return >0 if @b is considered better. */
1469 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1470 {
1471         struct wpa_scan_res **_wa = (void *) a;
1472         struct wpa_scan_res **_wb = (void *) b;
1473         struct wpa_scan_res *wa = *_wa;
1474         struct wpa_scan_res *wb = *_wb;
1475         int uses_wps_a, uses_wps_b;
1476         struct wpabuf *wps_a, *wps_b;
1477         int res;
1478
1479         /* Optimization - check WPS IE existence before allocated memory and
1480          * doing full reassembly. */
1481         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1482         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1483         if (uses_wps_a && !uses_wps_b)
1484                 return -1;
1485         if (!uses_wps_a && uses_wps_b)
1486                 return 1;
1487
1488         if (uses_wps_a && uses_wps_b) {
1489                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1490                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1491                 res = wps_ap_priority_compar(wps_a, wps_b);
1492                 wpabuf_free(wps_a);
1493                 wpabuf_free(wps_b);
1494                 if (res)
1495                         return res;
1496         }
1497
1498         /*
1499          * Do not use current AP security policy as a sorting criteria during
1500          * WPS provisioning step since the AP may get reconfigured at the
1501          * completion of provisioning.
1502          */
1503
1504         /* all things being equal, use signal level; if signal levels are
1505          * identical, use quality values since some drivers may only report
1506          * that value and leave the signal level zero */
1507         if (wb->level == wa->level)
1508                 return wb->qual - wa->qual;
1509         return wb->level - wa->level;
1510 }
1511 #endif /* CONFIG_WPS */
1512
1513
1514 static void dump_scan_res(struct wpa_scan_results *scan_res)
1515 {
1516 #ifndef CONFIG_NO_STDOUT_DEBUG
1517         size_t i;
1518
1519         if (scan_res->res == NULL || scan_res->num == 0)
1520                 return;
1521
1522         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1523
1524         for (i = 0; i < scan_res->num; i++) {
1525                 struct wpa_scan_res *r = scan_res->res[i];
1526                 u8 *pos;
1527                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1528                     == WPA_SCAN_LEVEL_DBM) {
1529                         int snr = r->level - r->noise;
1530                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1531                                    "noise=%d level=%d snr=%d%s flags=0x%x "
1532                                    "age=%u",
1533                                    MAC2STR(r->bssid), r->freq, r->qual,
1534                                    r->noise, r->level, snr,
1535                                    snr >= GREAT_SNR ? "*" : "", r->flags,
1536                                    r->age);
1537                 } else {
1538                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1539                                    "noise=%d level=%d flags=0x%x age=%u",
1540                                    MAC2STR(r->bssid), r->freq, r->qual,
1541                                    r->noise, r->level, r->flags, r->age);
1542                 }
1543                 pos = (u8 *) (r + 1);
1544                 if (r->ie_len)
1545                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1546                 pos += r->ie_len;
1547                 if (r->beacon_ie_len)
1548                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1549                                     pos, r->beacon_ie_len);
1550         }
1551 #endif /* CONFIG_NO_STDOUT_DEBUG */
1552 }
1553
1554
1555 /**
1556  * wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
1557  * @wpa_s: Pointer to wpa_supplicant data
1558  * @bssid: BSSID to check
1559  * Returns: 0 if the BSSID is filtered or 1 if not
1560  *
1561  * This function is used to filter out specific BSSIDs from scan reslts mainly
1562  * for testing purposes (SET bssid_filter ctrl_iface command).
1563  */
1564 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1565                                       const u8 *bssid)
1566 {
1567         size_t i;
1568
1569         if (wpa_s->bssid_filter == NULL)
1570                 return 1;
1571
1572         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1573                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1574                               ETH_ALEN) == 0)
1575                         return 1;
1576         }
1577
1578         return 0;
1579 }
1580
1581
1582 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1583                             struct wpa_scan_results *res)
1584 {
1585         size_t i, j;
1586
1587         if (wpa_s->bssid_filter == NULL)
1588                 return;
1589
1590         for (i = 0, j = 0; i < res->num; i++) {
1591                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1592                                                       res->res[i]->bssid)) {
1593                         res->res[j++] = res->res[i];
1594                 } else {
1595                         os_free(res->res[i]);
1596                         res->res[i] = NULL;
1597                 }
1598         }
1599
1600         if (res->num != j) {
1601                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1602                            (int) (res->num - j));
1603                 res->num = j;
1604         }
1605 }
1606
1607
1608 /**
1609  * wpa_supplicant_get_scan_results - Get scan results
1610  * @wpa_s: Pointer to wpa_supplicant data
1611  * @info: Information about what was scanned or %NULL if not available
1612  * @new_scan: Whether a new scan was performed
1613  * Returns: Scan results, %NULL on failure
1614  *
1615  * This function request the current scan results from the driver and updates
1616  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1617  * results with wpa_scan_results_free().
1618  */
1619 struct wpa_scan_results *
1620 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1621                                 struct scan_info *info, int new_scan)
1622 {
1623         struct wpa_scan_results *scan_res;
1624         size_t i;
1625         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1626
1627         scan_res = wpa_drv_get_scan_results2(wpa_s);
1628         if (scan_res == NULL) {
1629                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1630                 return NULL;
1631         }
1632         if (scan_res->fetch_time.sec == 0) {
1633                 /*
1634                  * Make sure we have a valid timestamp if the driver wrapper
1635                  * does not set this.
1636                  */
1637                 os_get_time(&scan_res->fetch_time);
1638         }
1639         filter_scan_res(wpa_s, scan_res);
1640
1641 #ifdef CONFIG_WPS
1642         if (wpas_wps_in_progress(wpa_s)) {
1643                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1644                         "provisioning rules");
1645                 compar = wpa_scan_result_wps_compar;
1646         }
1647 #endif /* CONFIG_WPS */
1648
1649         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1650               compar);
1651         dump_scan_res(scan_res);
1652
1653         wpa_bss_update_start(wpa_s);
1654         for (i = 0; i < scan_res->num; i++)
1655                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
1656                                         &scan_res->fetch_time);
1657         wpa_bss_update_end(wpa_s, info, new_scan);
1658
1659         return scan_res;
1660 }
1661
1662
1663 /**
1664  * wpa_supplicant_update_scan_results - Update scan results from the driver
1665  * @wpa_s: Pointer to wpa_supplicant data
1666  * Returns: 0 on success, -1 on failure
1667  *
1668  * This function updates the BSS table within wpa_supplicant based on the
1669  * currently available scan results from the driver without requesting a new
1670  * scan. This is used in cases where the driver indicates an association
1671  * (including roaming within ESS) and wpa_supplicant does not yet have the
1672  * needed information to complete the connection (e.g., to perform validation
1673  * steps in 4-way handshake).
1674  */
1675 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1676 {
1677         struct wpa_scan_results *scan_res;
1678         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1679         if (scan_res == NULL)
1680                 return -1;
1681         wpa_scan_results_free(scan_res);
1682
1683         return 0;
1684 }
1685
1686
1687 /**
1688  * scan_only_handler - Reports scan results
1689  */
1690 void scan_only_handler(struct wpa_supplicant *wpa_s,
1691                        struct wpa_scan_results *scan_res)
1692 {
1693         wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
1694         wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
1695         wpas_notify_scan_results(wpa_s);
1696         wpas_notify_scan_done(wpa_s, 1);
1697 }
1698
1699
1700 int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
1701 {
1702         return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
1703 }