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 static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
 488                                           u16 num_modes,
 489                                           enum hostapd_hw_mode mode)
 490 {
 491         u16 i;
 492
 493         for (i = 0; i < num_modes; i++) {
 494                 if (modes[i].mode == mode)
 495                         return &modes[i];
 496         }
 497
 498         return NULL;
 499 }
 500
 501
 502 static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
 503                                         enum hostapd_hw_mode band,
 504                                         struct wpa_driver_scan_params *params)
 505 {
 506         /* Include only supported channels for the specified band */
 507         struct hostapd_hw_modes *mode;
 508         int count, i;
 509
 510         mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
 511         if (mode == NULL) {
 512                 /* No channels supported in this band - use empty list */
 513                 params->freqs = os_zalloc(sizeof(int));
 514                 return;
 515         }
 516
 517         params->freqs = os_zalloc((mode->num_channels + 1) * sizeof(int));
 518         if (params->freqs == NULL)
 519                 return;
 520         for (count = 0, i = 0; i < mode->num_channels; i++) {
 521                 if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
 522                         continue;
 523                 params->freqs[count++] = mode->channels[i].freq;
 524         }
 525 }
 526
 527
 528 static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
 529                                    struct wpa_driver_scan_params *params)
 530 {
 531         if (wpa_s->hw.modes == NULL)
 532                 return; /* unknown what channels the driver supports */
 533         if (params->freqs)
 534                 return; /* already using a limited channel set */
 535         if (wpa_s->setband == WPA_SETBAND_5G)
 536                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
 537                                             params);
 538         else if (wpa_s->setband == WPA_SETBAND_2G)
 539                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
 540                                             params);
 541 }
 542
 543
 544 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 545 {
 546         struct wpa_supplicant *wpa_s = eloop_ctx;
 547         struct wpa_ssid *ssid;
 548         enum scan_req_type scan_req = NORMAL_SCAN_REQ;
 549         int ret;
 550         struct wpabuf *extra_ie = NULL;
 551         struct wpa_driver_scan_params params;
 552         struct wpa_driver_scan_params *scan_params;
 553         size_t max_ssids;
 554         enum wpa_states prev_state;
 555
 556         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 557                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 558                 wpas_p2p_continue_after_scan(wpa_s);
 559                 return;
 560         }
 561
 562         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
 563                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
 564                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 565                 wpas_p2p_continue_after_scan(wpa_s);
 566                 return;
 567         }
 568
 569         if (!wpa_supplicant_enabled_networks(wpa_s) &&
 570             wpa_s->scan_req == NORMAL_SCAN_REQ) {
 571                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 572                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 573                 wpas_p2p_continue_after_scan(wpa_s);
 574                 return;
 575         }
 576
 577         if (wpa_s->conf->ap_scan != 0 &&
 578             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 579                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 580                         "overriding ap_scan configuration");
 581                 wpa_s->conf->ap_scan = 0;
 582                 wpas_notify_ap_scan_changed(wpa_s);
 583         }
 584
 585         if (wpa_s->conf->ap_scan == 0) {
 586                 wpa_supplicant_gen_assoc_event(wpa_s);
 587                 return;
 588         }
 589
 590 #ifdef CONFIG_P2P
 591         if (wpas_p2p_in_progress(wpa_s) || wpas_wpa_is_in_progress(wpa_s)) {
 592                 if (wpa_s->sta_scan_pending &&
 593                     wpas_p2p_in_progress(wpa_s) == 2 &&
 594                     wpa_s->global->p2p_cb_on_scan_complete) {
 595                         wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
 596                                 "mode scan during P2P search");
 597                 } else {
 598                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 599                                 "while P2P operation is in progress");
 600                         wpa_s->sta_scan_pending = 1;
 601                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 602                         return;
 603                 }
 604         }
 605 #endif /* CONFIG_P2P */
 606
 607         if (wpa_s->conf->ap_scan == 2)
 608                 max_ssids = 1;
 609         else {
 610                 max_ssids = wpa_s->max_scan_ssids;
 611                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 612                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 613         }
 614
 615         scan_req = wpa_s->scan_req;
 616         wpa_s->scan_req = NORMAL_SCAN_REQ;
 617
 618         os_memset(&params, 0, sizeof(params));
 619
 620         prev_state = wpa_s->wpa_state;
 621         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 622             wpa_s->wpa_state == WPA_INACTIVE)
 623                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 624
 625         /*
 626          * If autoscan has set its own scanning parameters
 627          */
 628         if (wpa_s->autoscan_params != NULL) {
 629                 scan_params = wpa_s->autoscan_params;
 630                 goto scan;
 631         }
 632
 633         if (scan_req != MANUAL_SCAN_REQ && wpa_s->connect_without_scan) {
 634                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 635                         if (ssid == wpa_s->connect_without_scan)
 636                                 break;
 637                 }
 638                 wpa_s->connect_without_scan = NULL;
 639                 if (ssid) {
 640                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 641                                    "without scan step");
 642                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 643                         return;
 644                 }
 645         }
 646
 647 #ifdef CONFIG_P2P
 648         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
 649             wpa_s->go_params) {
 650                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during "
 651                            "P2P group formation");
 652                 params.ssids[0].ssid = wpa_s->go_params->ssid;
 653                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
 654                 params.num_ssids = 1;
 655                 goto ssid_list_set;
 656         }
 657 #endif /* CONFIG_P2P */
 658
 659         /* Find the starting point from which to continue scanning */
 660         ssid = wpa_s->conf->ssid;
 661         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 662                 while (ssid) {
 663                         if (ssid == wpa_s->prev_scan_ssid) {
 664                                 ssid = ssid->next;
 665                                 break;
 666                         }
 667                         ssid = ssid->next;
 668                 }
 669         }
 670
 671         if (scan_req != MANUAL_SCAN_REQ && wpa_s->conf->ap_scan == 2) {
 672                 wpa_s->connect_without_scan = NULL;
 673                 wpa_s->prev_scan_wildcard = 0;
 674                 wpa_supplicant_assoc_try(wpa_s, ssid);
 675                 return;
 676         } else if (wpa_s->conf->ap_scan == 2) {
 677                 /*
 678                  * User-initiated scan request in ap_scan == 2; scan with
 679                  * wildcard SSID.
 680                  */
 681                 ssid = NULL;
 682         } else {
 683                 struct wpa_ssid *start = ssid, *tssid;
 684                 int freqs_set = 0;
 685                 if (ssid == NULL && max_ssids > 1)
 686                         ssid = wpa_s->conf->ssid;
 687                 while (ssid) {
 688                         if (!wpas_network_disabled(wpa_s, ssid) &&
 689                             ssid->scan_ssid) {
 690                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 691                                                   ssid->ssid, ssid->ssid_len);
 692                                 params.ssids[params.num_ssids].ssid =
 693                                         ssid->ssid;
 694                                 params.ssids[params.num_ssids].ssid_len =
 695                                         ssid->ssid_len;
 696                                 params.num_ssids++;
 697                                 if (params.num_ssids + 1 >= max_ssids)
 698                                         break;
 699                         }
 700                         ssid = ssid->next;
 701                         if (ssid == start)
 702                                 break;
 703                         if (ssid == NULL && max_ssids > 1 &&
 704                             start != wpa_s->conf->ssid)
 705                                 ssid = wpa_s->conf->ssid;
 706                 }
 707
 708                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 709                         if (wpas_network_disabled(wpa_s, tssid))
 710                                 continue;
 711                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 712                                 int_array_concat(&params.freqs,
 713                                                  tssid->scan_freq);
 714                         } else {
 715                                 os_free(params.freqs);
 716                                 params.freqs = NULL;
 717                         }
 718                         freqs_set = 1;
 719                 }
 720                 int_array_sort_unique(params.freqs);
 721         }
 722
 723         if (ssid && max_ssids == 1) {
 724                 /*
 725                  * If the driver is limited to 1 SSID at a time interleave
 726                  * wildcard SSID scans with specific SSID scans to avoid
 727                  * waiting a long time for a wildcard scan.
 728                  */
 729                 if (!wpa_s->prev_scan_wildcard) {
 730                         params.ssids[0].ssid = NULL;
 731                         params.ssids[0].ssid_len = 0;
 732                         wpa_s->prev_scan_wildcard = 1;
 733                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 734                                 "wildcard SSID (Interleave with specific)");
 735                 } else {
 736                         wpa_s->prev_scan_ssid = ssid;
 737                         wpa_s->prev_scan_wildcard = 0;
 738                         wpa_dbg(wpa_s, MSG_DEBUG,
 739                                 "Starting AP scan for specific SSID: %s",
 740                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 741                 }
 742         } else if (ssid) {
 743                 /* max_ssids > 1 */
 744
 745                 wpa_s->prev_scan_ssid = ssid;
 746                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 747                         "the scan request");
 748                 params.num_ssids++;
 749         } else {
 750                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 751                 params.num_ssids++;
 752                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 753                         "SSID");
 754         }
 755 #ifdef CONFIG_P2P
 756 ssid_list_set:
 757 #endif /* CONFIG_P2P */
 758
 759         wpa_supplicant_optimize_freqs(wpa_s, &params);
 760         extra_ie = wpa_supplicant_extra_ies(wpa_s);
 761
 762         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 763                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 764                         "generated frequency list");
 765                 params.freqs = wpa_s->next_scan_freqs;
 766         } else
 767                 os_free(wpa_s->next_scan_freqs);
 768         wpa_s->next_scan_freqs = NULL;
 769         wpa_setband_scan_freqs(wpa_s, &params);
 770
 771         /* See if user specified frequencies. If so, scan only those. */
 772         if (wpa_s->conf->freq_list && !params.freqs) {
 773                 wpa_dbg(wpa_s, MSG_DEBUG,
 774                         "Optimize scan based on conf->freq_list");
 775                 int_array_concat(&params.freqs, wpa_s->conf->freq_list);
 776         }
 777
 778         /* Use current associated channel? */
 779         if (wpa_s->conf->scan_cur_freq && !params.freqs) {
 780                 unsigned int num = wpa_s->num_multichan_concurrent;
 781
 782                 params.freqs = os_calloc(num + 1, sizeof(int));
 783                 if (params.freqs) {
 784                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
 785                         if (num > 0) {
 786                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the "
 787                                         "current operating channels since "
 788                                         "scan_cur_freq is enabled");
 789                         } else {
 790                                 os_free(params.freqs);
 791                                 params.freqs = NULL;
 792                         }
 793                 }
 794         }
 795
 796         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 797                 wpa_s->conf, &params.num_filter_ssids);
 798         if (extra_ie) {
 799                 params.extra_ies = wpabuf_head(extra_ie);
 800                 params.extra_ies_len = wpabuf_len(extra_ie);
 801         }
 802
 803 #ifdef CONFIG_P2P
 804         if (wpa_s->p2p_in_provisioning ||
 805             (wpa_s->show_group_started && wpa_s->go_params)) {
 806                 /*
 807                  * The interface may not yet be in P2P mode, so we have to
 808                  * explicitly request P2P probe to disable CCK rates.
 809                  */
 810                 params.p2p_probe = 1;
 811         }
 812 #endif /* CONFIG_P2P */
 813
 814         scan_params = &params;
 815
 816 scan:
 817 #ifdef CONFIG_P2P
 818         /*
 819          * If the driver does not support multi-channel concurrency and a
 820          * virtual interface that shares the same radio with the wpa_s interface
 821          * is operating there may not be need to scan other channels apart from
 822          * the current operating channel on the other virtual interface. Filter
 823          * out other channels in case we are trying to find a connection for a
 824          * station interface when we are not configured to prefer station
 825          * connection and a concurrent operation is already in process.
 826          */
 827         if (wpa_s->scan_for_connection && scan_req == NORMAL_SCAN_REQ &&
 828             !scan_params->freqs && !params.freqs &&
 829             wpas_is_p2p_prioritized(wpa_s) &&
 830             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
 831             non_p2p_network_enabled(wpa_s)) {
 832                 unsigned int num = wpa_s->num_multichan_concurrent;
 833
 834                 params.freqs = os_calloc(num + 1, sizeof(int));
 835                 if (params.freqs) {
 836                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
 837                         if (num > 0 && num == wpa_s->num_multichan_concurrent) {
 838                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current operating channels since all channels are already used");
 839                         } else {
 840                                 os_free(params.freqs);
 841                                 params.freqs = NULL;
 842                         }
 843                 }
 844         }
 845 #endif /* CONFIG_P2P */
 846
 847         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
 848
 849         wpabuf_free(extra_ie);
 850         os_free(params.freqs);
 851         os_free(params.filter_ssids);
 852
 853         if (ret) {
 854                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 855                 if (prev_state != wpa_s->wpa_state)
 856                         wpa_supplicant_set_state(wpa_s, prev_state);
 857                 /* Restore scan_req since we will try to scan again */
 858                 wpa_s->scan_req = scan_req;
 859                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 860         } else {
 861                 wpa_s->scan_for_connection = 0;
 862         }
 863 }
 864
 865
 866 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
 867 {
 868         struct os_time remaining, new_int;
 869         int cancelled;
 870
 871         cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
 872                                              &remaining);
 873
 874         new_int.sec = sec;
 875         new_int.usec = 0;
 876         if (cancelled && os_time_before(&remaining, &new_int)) {
 877                 new_int.sec = remaining.sec;
 878                 new_int.usec = remaining.usec;
 879         }
 880
 881         eloop_register_timeout(new_int.sec, new_int.usec, wpa_supplicant_scan,
 882                                wpa_s, NULL);
 883         wpa_s->scan_interval = sec;
 884 }
 885
 886
 887 /**
 888  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 889  * @wpa_s: Pointer to wpa_supplicant data
 890  * @sec: Number of seconds after which to scan
 891  * @usec: Number of microseconds after which to scan
 892  *
 893  * This function is used to schedule a scan for neighboring access points after
 894  * the specified time.
 895  */
 896 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 897 {
 898         /* If there's at least one network that should be specifically scanned
 899          * then don't cancel the scan and reschedule.  Some drivers do
 900          * background scanning which generates frequent scan results, and that
 901          * causes the specific SSID scan to get continually pushed back and
 902          * never happen, which causes hidden APs to never get probe-scanned.
 903          */
 904         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 905             wpa_s->conf->ap_scan == 1) {
 906                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 907
 908                 while (ssid) {
 909                         if (!wpas_network_disabled(wpa_s, ssid) &&
 910                             ssid->scan_ssid)
 911                                 break;
 912                         ssid = ssid->next;
 913                 }
 914                 if (ssid) {
 915                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 916                                 "ensure that specific SSID scans occur");
 917                         return;
 918                 }
 919         }
 920
 921         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 922                 sec, usec);
 923         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 924         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 925 }
 926
 927
 928 /**
 929  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 930  * @wpa_s: Pointer to wpa_supplicant data
 931  * @sec: Number of seconds after which to scan
 932  * @usec: Number of microseconds after which to scan
 933  * Returns: 0 on success or -1 otherwise
 934  *
 935  * This function is used to schedule periodic scans for neighboring
 936  * access points after the specified time.
 937  */
 938 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 939                                       int sec, int usec)
 940 {
 941         if (!wpa_s->sched_scan_supported)
 942                 return -1;
 943
 944         eloop_register_timeout(sec, usec,
 945                                wpa_supplicant_delayed_sched_scan_timeout,
 946                                wpa_s, NULL);
 947
 948         return 0;
 949 }
 950
 951
 952 /**
 953  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 954  * @wpa_s: Pointer to wpa_supplicant data
 955  * Returns: 0 is sched_scan was started or -1 otherwise
 956  *
 957  * This function is used to schedule periodic scans for neighboring
 958  * access points repeating the scan continuously.
 959  */
 960 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 961 {
 962         struct wpa_driver_scan_params params;
 963         struct wpa_driver_scan_params *scan_params;
 964         enum wpa_states prev_state;
 965         struct wpa_ssid *ssid = NULL;
 966         struct wpabuf *extra_ie = NULL;
 967         int ret;
 968         unsigned int max_sched_scan_ssids;
 969         int wildcard = 0;
 970         int need_ssids;
 971
 972         if (!wpa_s->sched_scan_supported)
 973                 return -1;
 974
 975         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 976                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 977         else
 978                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 979         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
 980                 return -1;
 981
 982         if (wpa_s->sched_scanning) {
 983                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 984                 return 0;
 985         }
 986
 987         need_ssids = 0;
 988         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 989                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
 990                         /* Use wildcard SSID to find this network */
 991                         wildcard = 1;
 992                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
 993                            ssid->ssid_len)
 994                         need_ssids++;
 995
 996 #ifdef CONFIG_WPS
 997                 if (!wpas_network_disabled(wpa_s, ssid) &&
 998                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
 999                         /*
1000                          * Normal scan is more reliable and faster for WPS
1001                          * operations and since these are for short periods of
1002                          * time, the benefit of trying to use sched_scan would
1003                          * be limited.
1004                          */
1005                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1006                                 "sched_scan for WPS");
1007                         return -1;
1008                 }
1009 #endif /* CONFIG_WPS */
1010         }
1011         if (wildcard)
1012                 need_ssids++;
1013
1014         if (wpa_s->normal_scans < 3 &&
1015             (need_ssids <= wpa_s->max_scan_ssids ||
1016              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
1017                 /*
1018                  * When normal scan can speed up operations, use that for the
1019                  * first operations before starting the sched_scan to allow
1020                  * user space sleep more. We do this only if the normal scan
1021                  * has functionality that is suitable for this or if the
1022                  * sched_scan does not have better support for multiple SSIDs.
1023                  */
1024                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1025                         "sched_scan for initial scans (normal_scans=%d)",
1026                         wpa_s->normal_scans);
1027                 return -1;
1028         }
1029
1030         os_memset(&params, 0, sizeof(params));
1031
1032         /* If we can't allocate space for the filters, we just don't filter */
1033         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
1034                                         sizeof(struct wpa_driver_scan_filter));
1035
1036         prev_state = wpa_s->wpa_state;
1037         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
1038             wpa_s->wpa_state == WPA_INACTIVE)
1039                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
1040
1041         if (wpa_s->autoscan_params != NULL) {
1042                 scan_params = wpa_s->autoscan_params;
1043                 goto scan;
1044         }
1045
1046         /* Find the starting point from which to continue scanning */
1047         ssid = wpa_s->conf->ssid;
1048         if (wpa_s->prev_sched_ssid) {
1049                 while (ssid) {
1050                         if (ssid == wpa_s->prev_sched_ssid) {
1051                                 ssid = ssid->next;
1052                                 break;
1053                         }
1054                         ssid = ssid->next;
1055                 }
1056         }
1057
1058         if (!ssid || !wpa_s->prev_sched_ssid) {
1059                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
1060                 if (wpa_s->conf->sched_scan_interval)
1061                         wpa_s->sched_scan_interval =
1062                                 wpa_s->conf->sched_scan_interval;
1063                 if (wpa_s->sched_scan_interval == 0)
1064                         wpa_s->sched_scan_interval = 10;
1065                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1066                 wpa_s->first_sched_scan = 1;
1067                 ssid = wpa_s->conf->ssid;
1068                 wpa_s->prev_sched_ssid = ssid;
1069         }
1070
1071         if (wildcard) {
1072                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1073                 params.num_ssids++;
1074         }
1075
1076         while (ssid) {
1077                 if (wpas_network_disabled(wpa_s, ssid))
1078                         goto next;
1079
1080                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
1081                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1082                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1083                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1084                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1085                                   ssid->ssid, ssid->ssid_len);
1086                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1087                                 ssid->ssid_len;
1088                         params.num_filter_ssids++;
1089                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1090                 {
1091                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1092                                 "filter for sched_scan - drop filter");
1093                         os_free(params.filter_ssids);
1094                         params.filter_ssids = NULL;
1095                         params.num_filter_ssids = 0;
1096                 }
1097
1098                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1099                         if (params.num_ssids == max_sched_scan_ssids)
1100                                 break; /* only room for broadcast SSID */
1101                         wpa_dbg(wpa_s, MSG_DEBUG,
1102                                 "add to active scan ssid: %s",
1103                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1104                         params.ssids[params.num_ssids].ssid =
1105                                 ssid->ssid;
1106                         params.ssids[params.num_ssids].ssid_len =
1107                                 ssid->ssid_len;
1108                         params.num_ssids++;
1109                         if (params.num_ssids >= max_sched_scan_ssids) {
1110                                 wpa_s->prev_sched_ssid = ssid;
1111                                 do {
1112                                         ssid = ssid->next;
1113                                 } while (ssid &&
1114                                          (wpas_network_disabled(wpa_s, ssid) ||
1115                                           !ssid->scan_ssid));
1116                                 break;
1117                         }
1118                 }
1119
1120         next:
1121                 wpa_s->prev_sched_ssid = ssid;
1122                 ssid = ssid->next;
1123         }
1124
1125         if (params.num_filter_ssids == 0) {
1126                 os_free(params.filter_ssids);
1127                 params.filter_ssids = NULL;
1128         }
1129
1130         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1131         if (extra_ie) {
1132                 params.extra_ies = wpabuf_head(extra_ie);
1133                 params.extra_ies_len = wpabuf_len(extra_ie);
1134         }
1135
1136         scan_params = &params;
1137
1138 scan:
1139         if (ssid || !wpa_s->first_sched_scan) {
1140                 wpa_dbg(wpa_s, MSG_DEBUG,
1141                         "Starting sched scan: interval %d timeout %d",
1142                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1143         } else {
1144                 wpa_dbg(wpa_s, MSG_DEBUG,
1145                         "Starting sched scan: interval %d (no timeout)",
1146                         wpa_s->sched_scan_interval);
1147         }
1148
1149         wpa_setband_scan_freqs(wpa_s, scan_params);
1150
1151         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1152                                               wpa_s->sched_scan_interval);
1153         wpabuf_free(extra_ie);
1154         os_free(params.filter_ssids);
1155         if (ret) {
1156                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1157                 if (prev_state != wpa_s->wpa_state)
1158                         wpa_supplicant_set_state(wpa_s, prev_state);
1159                 return ret;
1160         }
1161
1162         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1163         if (ssid || !wpa_s->first_sched_scan) {
1164                 wpa_s->sched_scan_timed_out = 0;
1165                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1166                                        wpa_supplicant_sched_scan_timeout,
1167                                        wpa_s, NULL);
1168                 wpa_s->first_sched_scan = 0;
1169                 wpa_s->sched_scan_timeout /= 2;
1170                 wpa_s->sched_scan_interval *= 2;
1171                 if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
1172                         wpa_s->sched_scan_interval = 10;
1173                         wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1174                 }
1175         }
1176
1177         /* If there is no more ssids, start next time from the beginning */
1178         if (!ssid)
1179                 wpa_s->prev_sched_ssid = NULL;
1180
1181         return 0;
1182 }
1183
1184
1185 /**
1186  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1187  * @wpa_s: Pointer to wpa_supplicant data
1188  *
1189  * This function is used to cancel a scan request scheduled with
1190  * wpa_supplicant_req_scan().
1191  */
1192 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1193 {
1194         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1195         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1196         wpas_p2p_continue_after_scan(wpa_s);
1197 }
1198
1199
1200 /**
1201  * wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
1202  * @wpa_s: Pointer to wpa_supplicant data
1203  *
1204  * This function is used to stop a delayed scheduled scan.
1205  */
1206 void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
1207 {
1208         if (!wpa_s->sched_scan_supported)
1209                 return;
1210
1211         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
1212         eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
1213                              wpa_s, NULL);
1214 }
1215
1216
1217 /**
1218  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1219  * @wpa_s: Pointer to wpa_supplicant data
1220  *
1221  * This function is used to stop a periodic scheduled scan.
1222  */
1223 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1224 {
1225         if (!wpa_s->sched_scanning)
1226                 return;
1227
1228         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1229         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1230         wpa_supplicant_stop_sched_scan(wpa_s);
1231 }
1232
1233
1234 /**
1235  * wpa_supplicant_notify_scanning - Indicate possible scan state change
1236  * @wpa_s: Pointer to wpa_supplicant data
1237  * @scanning: Whether scanning is currently in progress
1238  *
1239  * This function is to generate scanning notifycations. It is called whenever
1240  * there may have been a change in scanning (scan started, completed, stopped).
1241  * wpas_notify_scanning() is called whenever the scanning state changed from the
1242  * previously notified state.
1243  */
1244 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1245                                     int scanning)
1246 {
1247         if (wpa_s->scanning != scanning) {
1248                 wpa_s->scanning = scanning;
1249                 wpas_notify_scanning(wpa_s);
1250         }
1251 }
1252
1253
1254 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1255 {
1256         int rate = 0;
1257         const u8 *ie;
1258         int i;
1259
1260         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1261         for (i = 0; ie && i < ie[1]; i++) {
1262                 if ((ie[i + 2] & 0x7f) > rate)
1263                         rate = ie[i + 2] & 0x7f;
1264         }
1265
1266         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1267         for (i = 0; ie && i < ie[1]; i++) {
1268                 if ((ie[i + 2] & 0x7f) > rate)
1269                         rate = ie[i + 2] & 0x7f;
1270         }
1271
1272         return rate;
1273 }
1274
1275
1276 /**
1277  * wpa_scan_get_ie - Fetch a specified information element from a scan result
1278  * @res: Scan result entry
1279  * @ie: Information element identitifier (WLAN_EID_*)
1280  * Returns: Pointer to the information element (id field) or %NULL if not found
1281  *
1282  * This function returns the first matching information element in the scan
1283  * result.
1284  */
1285 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1286 {
1287         const u8 *end, *pos;
1288
1289         pos = (const u8 *) (res + 1);
1290         end = pos + res->ie_len;
1291
1292         while (pos + 1 < end) {
1293                 if (pos + 2 + pos[1] > end)
1294                         break;
1295                 if (pos[0] == ie)
1296                         return pos;
1297                 pos += 2 + pos[1];
1298         }
1299
1300         return NULL;
1301 }
1302
1303
1304 /**
1305  * wpa_scan_get_vendor_ie - Fetch vendor information element from a scan result
1306  * @res: Scan result entry
1307  * @vendor_type: Vendor type (four octets starting the IE payload)
1308  * Returns: Pointer to the information element (id field) or %NULL if not found
1309  *
1310  * This function returns the first matching information element in the scan
1311  * result.
1312  */
1313 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1314                                   u32 vendor_type)
1315 {
1316         const u8 *end, *pos;
1317
1318         pos = (const u8 *) (res + 1);
1319         end = pos + res->ie_len;
1320
1321         while (pos + 1 < end) {
1322                 if (pos + 2 + pos[1] > end)
1323                         break;
1324                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1325                     vendor_type == WPA_GET_BE32(&pos[2]))
1326                         return pos;
1327                 pos += 2 + pos[1];
1328         }
1329
1330         return NULL;
1331 }
1332
1333
1334 /**
1335  * wpa_scan_get_vendor_ie_beacon - Fetch vendor information from a scan result
1336  * @res: Scan result entry
1337  * @vendor_type: Vendor type (four octets starting the IE payload)
1338  * Returns: Pointer to the information element (id field) or %NULL if not found
1339  *
1340  * This function returns the first matching information element in the scan
1341  * result.
1342  *
1343  * This function is like wpa_scan_get_vendor_ie(), but uses IE buffer only
1344  * from Beacon frames instead of either Beacon or Probe Response frames.
1345  */
1346 const u8 * wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res *res,
1347                                          u32 vendor_type)
1348 {
1349         const u8 *end, *pos;
1350
1351         if (res->beacon_ie_len == 0)
1352                 return NULL;
1353
1354         pos = (const u8 *) (res + 1);
1355         pos += res->ie_len;
1356         end = pos + res->beacon_ie_len;
1357
1358         while (pos + 1 < end) {
1359                 if (pos + 2 + pos[1] > end)
1360                         break;
1361                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1362                     vendor_type == WPA_GET_BE32(&pos[2]))
1363                         return pos;
1364                 pos += 2 + pos[1];
1365         }
1366
1367         return NULL;
1368 }
1369
1370
1371 /**
1372  * wpa_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
1373  * @res: Scan result entry
1374  * @vendor_type: Vendor type (four octets starting the IE payload)
1375  * Returns: Pointer to the information element payload or %NULL if not found
1376  *
1377  * This function returns concatenated payload of possibly fragmented vendor
1378  * specific information elements in the scan result. The caller is responsible
1379  * for freeing the returned buffer.
1380  */
1381 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1382                                              u32 vendor_type)
1383 {
1384         struct wpabuf *buf;
1385         const u8 *end, *pos;
1386
1387         buf = wpabuf_alloc(res->ie_len);
1388         if (buf == NULL)
1389                 return NULL;
1390
1391         pos = (const u8 *) (res + 1);
1392         end = pos + res->ie_len;
1393
1394         while (pos + 1 < end) {
1395                 if (pos + 2 + pos[1] > end)
1396                         break;
1397                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1398                     vendor_type == WPA_GET_BE32(&pos[2]))
1399                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1400                 pos += 2 + pos[1];
1401         }
1402
1403         if (wpabuf_len(buf) == 0) {
1404                 wpabuf_free(buf);
1405                 buf = NULL;
1406         }
1407
1408         return buf;
1409 }
1410
1411
1412 /*
1413  * Channels with a great SNR can operate at full rate. What is a great SNR?
1414  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1415  * rule of thumb is that any SNR above 20 is good." This one
1416  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1417  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1418  * conservative value.
1419  */
1420 #define GREAT_SNR 30
1421
1422 /* Compare function for sorting scan results. Return >0 if @b is considered
1423  * better. */
1424 static int wpa_scan_result_compar(const void *a, const void *b)
1425 {
1426 #define IS_5GHZ(n) (n > 4000)
1427 #define MIN(a,b) a < b ? a : b
1428         struct wpa_scan_res **_wa = (void *) a;
1429         struct wpa_scan_res **_wb = (void *) b;
1430         struct wpa_scan_res *wa = *_wa;
1431         struct wpa_scan_res *wb = *_wb;
1432         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1433         int snr_a, snr_b;
1434
1435         /* WPA/WPA2 support preferred */
1436         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1437                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1438         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1439                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1440
1441         if (wpa_b && !wpa_a)
1442                 return 1;
1443         if (!wpa_b && wpa_a)
1444                 return -1;
1445
1446         /* privacy support preferred */
1447         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1448             (wb->caps & IEEE80211_CAP_PRIVACY))
1449                 return 1;
1450         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1451             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1452                 return -1;
1453
1454         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1455             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1456                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1457                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1458         } else {
1459                 /* Not suitable information to calculate SNR, so use level */
1460                 snr_a = wa->level;
1461                 snr_b = wb->level;
1462         }
1463
1464         /* best/max rate preferred if SNR close enough */
1465         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1466             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1467                 maxrate_a = wpa_scan_get_max_rate(wa);
1468                 maxrate_b = wpa_scan_get_max_rate(wb);
1469                 if (maxrate_a != maxrate_b)
1470                         return maxrate_b - maxrate_a;
1471                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1472                         return IS_5GHZ(wa->freq) ? -1 : 1;
1473         }
1474
1475         /* use freq for channel preference */
1476
1477         /* all things being equal, use SNR; if SNRs are
1478          * identical, use quality values since some drivers may only report
1479          * that value and leave the signal level zero */
1480         if (snr_b == snr_a)
1481                 return wb->qual - wa->qual;
1482         return snr_b - snr_a;
1483 #undef MIN
1484 #undef IS_5GHZ
1485 }
1486
1487
1488 #ifdef CONFIG_WPS
1489 /* Compare function for sorting scan results when searching a WPS AP for
1490  * provisioning. Return >0 if @b is considered better. */
1491 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1492 {
1493         struct wpa_scan_res **_wa = (void *) a;
1494         struct wpa_scan_res **_wb = (void *) b;
1495         struct wpa_scan_res *wa = *_wa;
1496         struct wpa_scan_res *wb = *_wb;
1497         int uses_wps_a, uses_wps_b;
1498         struct wpabuf *wps_a, *wps_b;
1499         int res;
1500
1501         /* Optimization - check WPS IE existence before allocated memory and
1502          * doing full reassembly. */
1503         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1504         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1505         if (uses_wps_a && !uses_wps_b)
1506                 return -1;
1507         if (!uses_wps_a && uses_wps_b)
1508                 return 1;
1509
1510         if (uses_wps_a && uses_wps_b) {
1511                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1512                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1513                 res = wps_ap_priority_compar(wps_a, wps_b);
1514                 wpabuf_free(wps_a);
1515                 wpabuf_free(wps_b);
1516                 if (res)
1517                         return res;
1518         }
1519
1520         /*
1521          * Do not use current AP security policy as a sorting criteria during
1522          * WPS provisioning step since the AP may get reconfigured at the
1523          * completion of provisioning.
1524          */
1525
1526         /* all things being equal, use signal level; if signal levels are
1527          * identical, use quality values since some drivers may only report
1528          * that value and leave the signal level zero */
1529         if (wb->level == wa->level)
1530                 return wb->qual - wa->qual;
1531         return wb->level - wa->level;
1532 }
1533 #endif /* CONFIG_WPS */
1534
1535
1536 static void dump_scan_res(struct wpa_scan_results *scan_res)
1537 {
1538 #ifndef CONFIG_NO_STDOUT_DEBUG
1539         size_t i;
1540
1541         if (scan_res->res == NULL || scan_res->num == 0)
1542                 return;
1543
1544         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1545
1546         for (i = 0; i < scan_res->num; i++) {
1547                 struct wpa_scan_res *r = scan_res->res[i];
1548                 u8 *pos;
1549                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1550                     == WPA_SCAN_LEVEL_DBM) {
1551                         int snr = r->level - r->noise;
1552                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1553                                    "noise=%d level=%d snr=%d%s flags=0x%x "
1554                                    "age=%u",
1555                                    MAC2STR(r->bssid), r->freq, r->qual,
1556                                    r->noise, r->level, snr,
1557                                    snr >= GREAT_SNR ? "*" : "", r->flags,
1558                                    r->age);
1559                 } else {
1560                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1561                                    "noise=%d level=%d flags=0x%x age=%u",
1562                                    MAC2STR(r->bssid), r->freq, r->qual,
1563                                    r->noise, r->level, r->flags, r->age);
1564                 }
1565                 pos = (u8 *) (r + 1);
1566                 if (r->ie_len)
1567                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1568                 pos += r->ie_len;
1569                 if (r->beacon_ie_len)
1570                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1571                                     pos, r->beacon_ie_len);
1572         }
1573 #endif /* CONFIG_NO_STDOUT_DEBUG */
1574 }
1575
1576
1577 /**
1578  * wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
1579  * @wpa_s: Pointer to wpa_supplicant data
1580  * @bssid: BSSID to check
1581  * Returns: 0 if the BSSID is filtered or 1 if not
1582  *
1583  * This function is used to filter out specific BSSIDs from scan reslts mainly
1584  * for testing purposes (SET bssid_filter ctrl_iface command).
1585  */
1586 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1587                                       const u8 *bssid)
1588 {
1589         size_t i;
1590
1591         if (wpa_s->bssid_filter == NULL)
1592                 return 1;
1593
1594         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1595                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1596                               ETH_ALEN) == 0)
1597                         return 1;
1598         }
1599
1600         return 0;
1601 }
1602
1603
1604 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1605                             struct wpa_scan_results *res)
1606 {
1607         size_t i, j;
1608
1609         if (wpa_s->bssid_filter == NULL)
1610                 return;
1611
1612         for (i = 0, j = 0; i < res->num; i++) {
1613                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1614                                                       res->res[i]->bssid)) {
1615                         res->res[j++] = res->res[i];
1616                 } else {
1617                         os_free(res->res[i]);
1618                         res->res[i] = NULL;
1619                 }
1620         }
1621
1622         if (res->num != j) {
1623                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1624                            (int) (res->num - j));
1625                 res->num = j;
1626         }
1627 }
1628
1629
1630 /**
1631  * wpa_supplicant_get_scan_results - Get scan results
1632  * @wpa_s: Pointer to wpa_supplicant data
1633  * @info: Information about what was scanned or %NULL if not available
1634  * @new_scan: Whether a new scan was performed
1635  * Returns: Scan results, %NULL on failure
1636  *
1637  * This function request the current scan results from the driver and updates
1638  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1639  * results with wpa_scan_results_free().
1640  */
1641 struct wpa_scan_results *
1642 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1643                                 struct scan_info *info, int new_scan)
1644 {
1645         struct wpa_scan_results *scan_res;
1646         size_t i;
1647         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1648
1649         scan_res = wpa_drv_get_scan_results2(wpa_s);
1650         if (scan_res == NULL) {
1651                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1652                 return NULL;
1653         }
1654         if (scan_res->fetch_time.sec == 0) {
1655                 /*
1656                  * Make sure we have a valid timestamp if the driver wrapper
1657                  * does not set this.
1658                  */
1659                 os_get_time(&scan_res->fetch_time);
1660         }
1661         filter_scan_res(wpa_s, scan_res);
1662
1663 #ifdef CONFIG_WPS
1664         if (wpas_wps_in_progress(wpa_s)) {
1665                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1666                         "provisioning rules");
1667                 compar = wpa_scan_result_wps_compar;
1668         }
1669 #endif /* CONFIG_WPS */
1670
1671         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1672               compar);
1673         dump_scan_res(scan_res);
1674
1675         wpa_bss_update_start(wpa_s);
1676         for (i = 0; i < scan_res->num; i++)
1677                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
1678                                         &scan_res->fetch_time);
1679         wpa_bss_update_end(wpa_s, info, new_scan);
1680
1681         return scan_res;
1682 }
1683
1684
1685 /**
1686  * wpa_supplicant_update_scan_results - Update scan results from the driver
1687  * @wpa_s: Pointer to wpa_supplicant data
1688  * Returns: 0 on success, -1 on failure
1689  *
1690  * This function updates the BSS table within wpa_supplicant based on the
1691  * currently available scan results from the driver without requesting a new
1692  * scan. This is used in cases where the driver indicates an association
1693  * (including roaming within ESS) and wpa_supplicant does not yet have the
1694  * needed information to complete the connection (e.g., to perform validation
1695  * steps in 4-way handshake).
1696  */
1697 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1698 {
1699         struct wpa_scan_results *scan_res;
1700         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1701         if (scan_res == NULL)
1702                 return -1;
1703         wpa_scan_results_free(scan_res);
1704
1705         return 0;
1706 }
1707
1708
1709 /**
1710  * scan_only_handler - Reports scan results
1711  */
1712 void scan_only_handler(struct wpa_supplicant *wpa_s,
1713                        struct wpa_scan_results *scan_res)
1714 {
1715         wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
1716         wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
1717         wpas_notify_scan_results(wpa_s);
1718         wpas_notify_scan_done(wpa_s, 1);
1719 }
1720
1721
1722 int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
1723 {
1724         return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
1725 }