wpa_supplicant/scan.c

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