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