wpa_supplicant/scan.c

   1 /*
   2  * WPA Supplicant - Scanning
   3  * Copyright (c) 2003-2010, 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 "config.h"
  15 #include "wpa_supplicant_i.h"
  16 #include "driver_i.h"
  17 #include "wps_supplicant.h"
  18 #include "p2p_supplicant.h"
  19 #include "p2p/p2p.h"
  20 #include "hs20_supplicant.h"
  21 #include "notify.h"
  22 #include "bss.h"
  23 #include "scan.h"
  24
  25
  26 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  27 {
  28         struct wpa_ssid *ssid;
  29         union wpa_event_data data;
  30
  31         ssid = wpa_supplicant_get_ssid(wpa_s);
  32         if (ssid == NULL)
  33                 return;
  34
  35         if (wpa_s->current_ssid == NULL) {
  36                 wpa_s->current_ssid = ssid;
  37                 if (wpa_s->current_ssid != NULL)
  38                         wpas_notify_network_changed(wpa_s);
  39         }
  40         wpa_supplicant_initiate_eapol(wpa_s);
  41         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
  42                 "network - generating associated event");
  43         os_memset(&data, 0, sizeof(data));
  44         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  45 }
  46
  47
  48 #ifdef CONFIG_WPS
  49 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
  50                            enum wps_request_type *req_type)
  51 {
  52         struct wpa_ssid *ssid;
  53         int wps = 0;
  54
  55         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
  56                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  57                         continue;
  58
  59                 wps = 1;
  60                 *req_type = wpas_wps_get_req_type(ssid);
  61                 if (!ssid->eap.phase1)
  62                         continue;
  63
  64                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  65                         return 2;
  66         }
  67
  68 #ifdef CONFIG_P2P
  69         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
  70             !wpa_s->conf->p2p_disabled) {
  71                 wpa_s->wps->dev.p2p = 1;
  72                 if (!wps) {
  73                         wps = 1;
  74                         *req_type = WPS_REQ_ENROLLEE_INFO;
  75                 }
  76         }
  77 #endif /* CONFIG_P2P */
  78
  79         return wps;
  80 }
  81 #endif /* CONFIG_WPS */
  82
  83
  84 int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
  85 {
  86         struct wpa_ssid *ssid = wpa_s->conf->ssid;
  87         int count = 0, disabled = 0;
  88         while (ssid) {
  89                 if (!wpas_network_disabled(wpa_s, ssid))
  90                         count++;
  91                 else
  92                         disabled++;
  93                 ssid = ssid->next;
  94         }
  95         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
  96             wpa_s->conf->auto_interworking)
  97                 count++;
  98         if (count == 0 && disabled > 0) {
  99                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
 100                         "networks)", disabled);
 101         }
 102         return count;
 103 }
 104
 105
 106 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
 107                                      struct wpa_ssid *ssid)
 108 {
 109         while (ssid) {
 110                 if (!wpas_network_disabled(wpa_s, ssid))
 111                         break;
 112                 ssid = ssid->next;
 113         }
 114
 115         /* ap_scan=2 mode - try to associate with each SSID. */
 116         if (ssid == NULL) {
 117                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 118                         "end of scan list - go back to beginning");
 119                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 120                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 121                 return;
 122         }
 123         if (ssid->next) {
 124                 /* Continue from the next SSID on the next attempt. */
 125                 wpa_s->prev_scan_ssid = ssid;
 126         } else {
 127                 /* Start from the beginning of the SSID list. */
 128                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 129         }
 130         wpa_supplicant_associate(wpa_s, NULL, ssid);
 131 }
 132
 133
 134 static int int_array_len(const int *a)
 135 {
 136         int i;
 137         for (i = 0; a && a[i]; i++)
 138                 ;
 139         return i;
 140 }
 141
 142
 143 static void int_array_concat(int **res, const int *a)
 144 {
 145         int reslen, alen, i;
 146         int *n;
 147
 148         reslen = int_array_len(*res);
 149         alen = int_array_len(a);
 150
 151         n = os_realloc_array(*res, reslen + alen + 1, sizeof(int));
 152         if (n == NULL) {
 153                 os_free(*res);
 154                 *res = NULL;
 155                 return;
 156         }
 157         for (i = 0; i <= alen; i++)
 158                 n[reslen + i] = a[i];
 159         *res = n;
 160 }
 161
 162
 163 static int freq_cmp(const void *a, const void *b)
 164 {
 165         int _a = *(int *) a;
 166         int _b = *(int *) b;
 167
 168         if (_a == 0)
 169                 return 1;
 170         if (_b == 0)
 171                 return -1;
 172         return _a - _b;
 173 }
 174
 175
 176 static void int_array_sort_unique(int *a)
 177 {
 178         int alen;
 179         int i, j;
 180
 181         if (a == NULL)
 182                 return;
 183
 184         alen = int_array_len(a);
 185         qsort(a, alen, sizeof(int), freq_cmp);
 186
 187         i = 0;
 188         j = 1;
 189         while (a[i] && a[j]) {
 190                 if (a[i] == a[j]) {
 191                         j++;
 192                         continue;
 193                 }
 194                 a[++i] = a[j++];
 195         }
 196         if (a[i])
 197                 i++;
 198         a[i] = 0;
 199 }
 200
 201
 202 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 203                                 struct wpa_driver_scan_params *params)
 204 {
 205         int ret;
 206
 207         wpa_supplicant_notify_scanning(wpa_s, 1);
 208
 209         ret = wpa_drv_scan(wpa_s, params);
 210         if (ret) {
 211                 wpa_supplicant_notify_scanning(wpa_s, 0);
 212                 wpas_notify_scan_done(wpa_s, 0);
 213         } else {
 214                 wpa_s->scan_runs++;
 215                 wpa_s->normal_scans++;
 216         }
 217
 218         return ret;
 219 }
 220
 221
 222 static void
 223 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 224 {
 225         struct wpa_supplicant *wpa_s = eloop_ctx;
 226
 227         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 228
 229         if (wpa_supplicant_req_sched_scan(wpa_s))
 230                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 231 }
 232
 233
 234 static void
 235 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 236 {
 237         struct wpa_supplicant *wpa_s = eloop_ctx;
 238
 239         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 240
 241         wpa_s->sched_scan_timed_out = 1;
 242         wpa_supplicant_cancel_sched_scan(wpa_s);
 243 }
 244
 245
 246 static int
 247 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 248                                 struct wpa_driver_scan_params *params,
 249                                 int interval)
 250 {
 251         int ret;
 252 #ifndef ANDROID_P2P
 253         wpa_supplicant_notify_scanning(wpa_s, 1);
 254 #endif
 255         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 256         if (ret)
 257                 wpa_supplicant_notify_scanning(wpa_s, 0);
 258         else {
 259                 wpa_s->sched_scanning = 1;
 260 #ifdef ANDROID_P2P
 261                 wpa_supplicant_notify_scanning(wpa_s, 1);
 262 #endif
 263         }
 264
 265         return ret;
 266 }
 267
 268
 269 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 270 {
 271         int ret;
 272
 273         ret = wpa_drv_stop_sched_scan(wpa_s);
 274         if (ret) {
 275                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 276                 /* TODO: what to do if stopping fails? */
 277                 return -1;
 278         }
 279
 280         return ret;
 281 }
 282
 283
 284 static struct wpa_driver_scan_filter *
 285 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 286 {
 287         struct wpa_driver_scan_filter *ssids;
 288         struct wpa_ssid *ssid;
 289         size_t count;
 290
 291         *num_ssids = 0;
 292         if (!conf->filter_ssids)
 293                 return NULL;
 294
 295         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 296                 if (ssid->ssid && ssid->ssid_len)
 297                         count++;
 298         }
 299         if (count == 0)
 300                 return NULL;
 301         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 302         if (ssids == NULL)
 303                 return NULL;
 304
 305         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 306                 if (!ssid->ssid || !ssid->ssid_len)
 307                         continue;
 308                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 309                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 310                 (*num_ssids)++;
 311         }
 312
 313         return ssids;
 314 }
 315
 316
 317 static void wpa_supplicant_optimize_freqs(
 318         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 319 {
 320 #ifdef CONFIG_P2P
 321         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 322             wpa_s->go_params) {
 323                 /* Optimize provisioning state scan based on GO information */
 324                 if (wpa_s->p2p_in_provisioning < 5 &&
 325                     wpa_s->go_params->freq > 0) {
 326                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 327                                 "preferred frequency %d MHz",
 328                                 wpa_s->go_params->freq);
 329                         params->freqs = os_zalloc(2 * sizeof(int));
 330                         if (params->freqs)
 331                                 params->freqs[0] = wpa_s->go_params->freq;
 332                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 333                            wpa_s->go_params->freq_list[0]) {
 334                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 335                                 "channels");
 336                         int_array_concat(&params->freqs,
 337                                          wpa_s->go_params->freq_list);
 338                         if (params->freqs)
 339                                 int_array_sort_unique(params->freqs);
 340                 }
 341                 wpa_s->p2p_in_provisioning++;
 342         }
 343 #endif /* CONFIG_P2P */
 344
 345 #ifdef CONFIG_WPS
 346         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 347                 /*
 348                  * Optimize post-provisioning scan based on channel used
 349                  * during provisioning.
 350                  */
 351                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 352                         "that was used during provisioning", wpa_s->wps_freq);
 353                 params->freqs = os_zalloc(2 * sizeof(int));
 354                 if (params->freqs)
 355                         params->freqs[0] = wpa_s->wps_freq;
 356                 wpa_s->after_wps--;
 357         }
 358
 359         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 360         {
 361                 /* Optimize provisioning scan based on already known channel */
 362                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 363                         wpa_s->wps_freq);
 364                 params->freqs = os_zalloc(2 * sizeof(int));
 365                 if (params->freqs)
 366                         params->freqs[0] = wpa_s->wps_freq;
 367                 wpa_s->known_wps_freq = 0; /* only do this once */
 368         }
 369 #endif /* CONFIG_WPS */
 370 }
 371
 372
 373 #ifdef CONFIG_INTERWORKING
 374 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 375                                            struct wpabuf *buf)
 376 {
 377         if (wpa_s->conf->interworking == 0)
 378                 return;
 379
 380         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 381         wpabuf_put_u8(buf, 4);
 382         wpabuf_put_u8(buf, 0x00);
 383         wpabuf_put_u8(buf, 0x00);
 384         wpabuf_put_u8(buf, 0x00);
 385         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 386
 387         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 388         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 389                       1 + ETH_ALEN);
 390         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 391         /* No Venue Info */
 392         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 393                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 394 }
 395 #endif /* CONFIG_INTERWORKING */
 396
 397
 398 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
 399 {
 400         struct wpabuf *extra_ie = NULL;
 401 #ifdef CONFIG_WPS
 402         int wps = 0;
 403         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 404 #endif /* CONFIG_WPS */
 405
 406 #ifdef CONFIG_INTERWORKING
 407         if (wpa_s->conf->interworking &&
 408             wpabuf_resize(&extra_ie, 100) == 0)
 409                 wpas_add_interworking_elements(wpa_s, extra_ie);
 410 #endif /* CONFIG_INTERWORKING */
 411
 412 #ifdef CONFIG_WPS
 413         wps = wpas_wps_in_use(wpa_s, &req_type);
 414
 415         if (wps) {
 416                 struct wpabuf *wps_ie;
 417                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
 418                                                 DEV_PW_DEFAULT,
 419                                                 &wpa_s->wps->dev,
 420                                                 wpa_s->wps->uuid, req_type,
 421                                                 0, NULL);
 422                 if (wps_ie) {
 423                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 424                                 wpabuf_put_buf(extra_ie, wps_ie);
 425                         wpabuf_free(wps_ie);
 426                 }
 427         }
 428
 429 #ifdef CONFIG_P2P
 430         if (wps) {
 431                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 432                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 433                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 434         }
 435 #endif /* CONFIG_P2P */
 436
 437 #endif /* CONFIG_WPS */
 438
 439         return extra_ie;
 440 }
 441
 442
 443 #ifdef CONFIG_P2P
 444
 445 /*
 446  * Check whether there are any enabled networks or credentials that could be
 447  * used for a non-P2P connection.
 448  */
 449 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
 450 {
 451         struct wpa_ssid *ssid;
 452
 453         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 454                 if (wpas_network_disabled(wpa_s, ssid))
 455                         continue;
 456                 if (!ssid->p2p_group)
 457                         return 1;
 458         }
 459
 460         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 461             wpa_s->conf->auto_interworking)
 462                 return 1;
 463
 464         return 0;
 465 }
 466
 467
 468 /*
 469  * Find the operating frequency of any other virtual interface that is using
 470  * the same radio concurrently.
 471  */
 472 static int shared_vif_oper_freq(struct wpa_supplicant *wpa_s)
 473 {
 474         const char *rn, *rn2;
 475         struct wpa_supplicant *ifs;
 476         u8 bssid[ETH_ALEN];
 477
 478         if (!wpa_s->driver->get_radio_name)
 479                 return -1;
 480
 481         rn = wpa_s->driver->get_radio_name(wpa_s->drv_priv);
 482         if (rn == NULL || rn[0] == '\0')
 483                 return -1;
 484
 485         for (ifs = wpa_s->global->ifaces; ifs; ifs = ifs->next) {
 486                 if (ifs == wpa_s || !ifs->driver->get_radio_name)
 487                         continue;
 488
 489                 rn2 = ifs->driver->get_radio_name(ifs->drv_priv);
 490                 if (!rn2 || os_strcmp(rn, rn2) != 0)
 491                         continue;
 492
 493                 if (ifs->current_ssid == NULL || ifs->assoc_freq == 0)
 494                         continue;
 495
 496                 if (ifs->current_ssid->mode == WPAS_MODE_AP ||
 497                     ifs->current_ssid->mode == WPAS_MODE_P2P_GO)
 498                         return ifs->current_ssid->frequency;
 499                 if (wpa_drv_get_bssid(ifs, bssid) == 0)
 500                         return ifs->assoc_freq;
 501         }
 502
 503         return 0;
 504 }
 505
 506 #endif /* CONFIG_P2P */
 507
 508
 509 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 510 {
 511         struct wpa_supplicant *wpa_s = eloop_ctx;
 512         struct wpa_ssid *ssid;
 513         enum scan_req_type scan_req = NORMAL_SCAN_REQ;
 514         int ret;
 515         struct wpabuf *extra_ie = NULL;
 516         struct wpa_driver_scan_params params;
 517         struct wpa_driver_scan_params *scan_params;
 518         size_t max_ssids;
 519         enum wpa_states prev_state;
 520
 521         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 522                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 523                 return;
 524         }
 525
 526         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
 527                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
 528                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 529                 return;
 530         }
 531 #ifdef ANDROID
 532         if (wpa_s->scanning) {
 533                 /* If we are already in scanning state, we shall ignore this new scan request*/
 534                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - already scanning");
 535                 return;
 536         }
 537 #endif
 538         if (!wpa_supplicant_enabled_networks(wpa_s) &&
 539             wpa_s->scan_req == NORMAL_SCAN_REQ) {
 540                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 541                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 542 #ifdef CONFIG_P2P
 543                 wpa_s->sta_scan_pending = 0;
 544 #endif /* CONFIG_P2P */
 545                 return;
 546         }
 547
 548         if (wpa_s->conf->ap_scan != 0 &&
 549             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 550                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 551                         "overriding ap_scan configuration");
 552                 wpa_s->conf->ap_scan = 0;
 553                 wpas_notify_ap_scan_changed(wpa_s);
 554         }
 555
 556         if (wpa_s->conf->ap_scan == 0) {
 557                 wpa_supplicant_gen_assoc_event(wpa_s);
 558                 return;
 559         }
 560
 561 #ifdef CONFIG_P2P
 562         if (wpas_p2p_in_progress(wpa_s)) {
 563                 if (wpa_s->sta_scan_pending &&
 564                     wpas_p2p_in_progress(wpa_s) == 2 &&
 565                     wpa_s->global->p2p_cb_on_scan_complete) {
 566                         wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
 567                                 "mode scan during P2P search");
 568                 } else {
 569                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 570                                 "while P2P operation is in progress");
 571                         wpa_s->sta_scan_pending = 1;
 572                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 573                         return;
 574                 }
 575         }
 576 #endif /* CONFIG_P2P */
 577
 578         if (wpa_s->conf->ap_scan == 2)
 579                 max_ssids = 1;
 580         else {
 581                 max_ssids = wpa_s->max_scan_ssids;
 582                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 583                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 584         }
 585
 586         scan_req = wpa_s->scan_req;
 587         wpa_s->scan_req = NORMAL_SCAN_REQ;
 588
 589         os_memset(&params, 0, sizeof(params));
 590
 591         prev_state = wpa_s->wpa_state;
 592         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 593             wpa_s->wpa_state == WPA_INACTIVE)
 594                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 595
 596         /*
 597          * If autoscan has set its own scanning parameters
 598          */
 599         if (wpa_s->autoscan_params != NULL) {
 600                 scan_params = wpa_s->autoscan_params;
 601                 goto scan;
 602         }
 603
 604         if (scan_req != MANUAL_SCAN_REQ && wpa_s->connect_without_scan) {
 605                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 606                         if (ssid == wpa_s->connect_without_scan)
 607                                 break;
 608                 }
 609                 wpa_s->connect_without_scan = NULL;
 610                 if (ssid) {
 611                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 612                                    "without scan step");
 613                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 614                         return;
 615                 }
 616         }
 617
 618 #ifdef CONFIG_P2P
 619         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
 620             wpa_s->go_params) {
 621                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during "
 622                            "P2P group formation");
 623                 params.ssids[0].ssid = wpa_s->go_params->ssid;
 624                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
 625                 params.num_ssids = 1;
 626                 goto ssid_list_set;
 627         }
 628 #endif /* CONFIG_P2P */
 629
 630         /* Find the starting point from which to continue scanning */
 631         ssid = wpa_s->conf->ssid;
 632         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 633                 while (ssid) {
 634                         if (ssid == wpa_s->prev_scan_ssid) {
 635                                 ssid = ssid->next;
 636                                 break;
 637                         }
 638                         ssid = ssid->next;
 639                 }
 640         }
 641
 642         if (scan_req != MANUAL_SCAN_REQ && wpa_s->conf->ap_scan == 2) {
 643                 wpa_s->connect_without_scan = NULL;
 644                 wpa_s->prev_scan_wildcard = 0;
 645                 wpa_supplicant_assoc_try(wpa_s, ssid);
 646                 return;
 647 #ifndef ANDROID
 648         } else if (wpa_s->conf->ap_scan == 2) {
 649                 /*
 650                  * User-initiated scan request in ap_scan == 2; scan with
 651                  * wildcard SSID.
 652                  */
 653                 ssid = NULL;
 654 #endif
 655         } else {
 656                 struct wpa_ssid *start = ssid, *tssid;
 657                 int freqs_set = 0;
 658                 if (ssid == NULL && max_ssids > 1)
 659                         ssid = wpa_s->conf->ssid;
 660                 while (ssid) {
 661                         if (!wpas_network_disabled(wpa_s, ssid) &&
 662                             ssid->scan_ssid) {
 663                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 664                                                   ssid->ssid, ssid->ssid_len);
 665                                 params.ssids[params.num_ssids].ssid =
 666                                         ssid->ssid;
 667                                 params.ssids[params.num_ssids].ssid_len =
 668                                         ssid->ssid_len;
 669                                 params.num_ssids++;
 670                                 if (params.num_ssids + 1 >= max_ssids)
 671                                         break;
 672                         }
 673                         ssid = ssid->next;
 674                         if (ssid == start)
 675                                 break;
 676                         if (ssid == NULL && max_ssids > 1 &&
 677                             start != wpa_s->conf->ssid)
 678                                 ssid = wpa_s->conf->ssid;
 679                 }
 680
 681                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 682                         if (wpas_network_disabled(wpa_s, tssid))
 683                                 continue;
 684                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 685                                 int_array_concat(&params.freqs,
 686                                                  tssid->scan_freq);
 687                         } else {
 688                                 os_free(params.freqs);
 689                                 params.freqs = NULL;
 690                         }
 691                         freqs_set = 1;
 692                 }
 693                 int_array_sort_unique(params.freqs);
 694         }
 695
 696         if (ssid && max_ssids == 1) {
 697                 /*
 698                  * If the driver is limited to 1 SSID at a time interleave
 699                  * wildcard SSID scans with specific SSID scans to avoid
 700                  * waiting a long time for a wildcard scan.
 701                  */
 702                 if (!wpa_s->prev_scan_wildcard) {
 703                         params.ssids[0].ssid = NULL;
 704                         params.ssids[0].ssid_len = 0;
 705                         wpa_s->prev_scan_wildcard = 1;
 706                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 707                                 "wildcard SSID (Interleave with specific)");
 708                 } else {
 709                         wpa_s->prev_scan_ssid = ssid;
 710                         wpa_s->prev_scan_wildcard = 0;
 711                         wpa_dbg(wpa_s, MSG_DEBUG,
 712                                 "Starting AP scan for specific SSID: %s",
 713                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 714                 }
 715         } else if (ssid) {
 716                 /* max_ssids > 1 */
 717
 718                 wpa_s->prev_scan_ssid = ssid;
 719                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 720                         "the scan request");
 721                 params.num_ssids++;
 722         } else {
 723                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 724                 params.num_ssids++;
 725                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 726                         "SSID");
 727         }
 728 #ifdef CONFIG_P2P
 729 ssid_list_set:
 730 #endif /* CONFIG_P2P */
 731
 732         wpa_supplicant_optimize_freqs(wpa_s, &params);
 733         extra_ie = wpa_supplicant_extra_ies(wpa_s);
 734
 735 #ifdef CONFIG_HS20
 736         if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 6) == 0)
 737                 wpas_hs20_add_indication(extra_ie);
 738 #endif /* CONFIG_HS20 */
 739
 740         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 741                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 742                         "generated frequency list");
 743                 params.freqs = wpa_s->next_scan_freqs;
 744         } else
 745                 os_free(wpa_s->next_scan_freqs);
 746         wpa_s->next_scan_freqs = NULL;
 747
 748         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 749                 wpa_s->conf, &params.num_filter_ssids);
 750         if (extra_ie) {
 751                 params.extra_ies = wpabuf_head(extra_ie);
 752                 params.extra_ies_len = wpabuf_len(extra_ie);
 753         }
 754
 755 #ifdef CONFIG_P2P
 756         if (wpa_s->p2p_in_provisioning ||
 757             (wpa_s->show_group_started && wpa_s->go_params)) {
 758                 /*
 759                  * The interface may not yet be in P2P mode, so we have to
 760                  * explicitly request P2P probe to disable CCK rates.
 761                  */
 762                 params.p2p_probe = 1;
 763         }
 764 #endif /* CONFIG_P2P */
 765
 766         scan_params = &params;
 767
 768 scan:
 769 #ifdef CONFIG_P2P
 770         /*
 771          * If the driver does not support multi-channel concurrency and a
 772          * virtual interface that shares the same radio with the wpa_s interface
 773          * is operating there may not be need to scan other channels apart from
 774          * the current operating channel on the other virtual interface. Filter
 775          * out other channels in case we are trying to find a connection for a
 776          * station interface when we are not configured to prefer station
 777          * connection and a concurrent operation is already in process.
 778          */
 779         if (wpa_s->scan_for_connection && scan_req == NORMAL_SCAN_REQ &&
 780             !scan_params->freqs && !params.freqs &&
 781             wpas_is_p2p_prioritized(wpa_s) &&
 782             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_MULTI_CHANNEL_CONCURRENT) &&
 783             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
 784             non_p2p_network_enabled(wpa_s)) {
 785                 int freq = shared_vif_oper_freq(wpa_s);
 786                 if (freq > 0) {
 787                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only the current "
 788                                 "operating channel (%d MHz) since driver does "
 789                                 "not support multi-channel concurrency", freq);
 790                         params.freqs = os_zalloc(sizeof(int) * 2);
 791                         if (params.freqs)
 792                                 params.freqs[0] = freq;
 793                         scan_params->freqs = params.freqs;
 794                 }
 795         }
 796 #endif /* CONFIG_P2P */
 797
 798         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
 799
 800         wpabuf_free(extra_ie);
 801         os_free(params.freqs);
 802         os_free(params.filter_ssids);
 803
 804         if (ret) {
 805                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 806                 if (prev_state != wpa_s->wpa_state)
 807                         wpa_supplicant_set_state(wpa_s, prev_state);
 808                 /* Restore scan_req since we will try to scan again */
 809                 wpa_s->scan_req = scan_req;
 810                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 811         } else {
 812                 wpa_s->scan_for_connection = 0;
 813         }
 814 }
 815
 816
 817 /**
 818  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 819  * @wpa_s: Pointer to wpa_supplicant data
 820  * @sec: Number of seconds after which to scan
 821  * @usec: Number of microseconds after which to scan
 822  *
 823  * This function is used to schedule a scan for neighboring access points after
 824  * the specified time.
 825  */
 826 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 827 {
 828 #ifndef ANDROID
 829         /* If there's at least one network that should be specifically scanned
 830          * then don't cancel the scan and reschedule.  Some drivers do
 831          * background scanning which generates frequent scan results, and that
 832          * causes the specific SSID scan to get continually pushed back and
 833          * never happen, which causes hidden APs to never get probe-scanned.
 834          */
 835         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 836             wpa_s->conf->ap_scan == 1) {
 837                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 838
 839                 while (ssid) {
 840                         if (!wpas_network_disabled(wpa_s, ssid) &&
 841                             ssid->scan_ssid)
 842                                 break;
 843                         ssid = ssid->next;
 844                 }
 845                 if (ssid) {
 846                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 847                                 "ensure that specific SSID scans occur");
 848                         return;
 849                 }
 850         }
 851 #endif
 852         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 853                 sec, usec);
 854         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 855         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 856 }
 857
 858
 859 /**
 860  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 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 periodic scans for neighboring
 866  * access points after the specified time.
 867  */
 868 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 869                                       int sec, int usec)
 870 {
 871         if (!wpa_s->sched_scan_supported)
 872                 return -1;
 873
 874         eloop_register_timeout(sec, usec,
 875                                wpa_supplicant_delayed_sched_scan_timeout,
 876                                wpa_s, NULL);
 877
 878         return 0;
 879 }
 880
 881
 882 /**
 883  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 884  * @wpa_s: Pointer to wpa_supplicant data
 885  *
 886  * This function is used to schedule periodic scans for neighboring
 887  * access points repeating the scan continuously.
 888  */
 889 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 890 {
 891         struct wpa_driver_scan_params params;
 892         struct wpa_driver_scan_params *scan_params;
 893         enum wpa_states prev_state;
 894         struct wpa_ssid *ssid = NULL;
 895         struct wpabuf *extra_ie = NULL;
 896         int ret;
 897         unsigned int max_sched_scan_ssids;
 898         int wildcard = 0;
 899         int need_ssids;
 900
 901         if (!wpa_s->sched_scan_supported)
 902                 return -1;
 903
 904         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 905                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 906         else
 907                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 908         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
 909                 return -1;
 910
 911         if (wpa_s->sched_scanning) {
 912                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 913                 return 0;
 914         }
 915
 916         need_ssids = 0;
 917         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 918                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
 919                         /* Use wildcard SSID to find this network */
 920                         wildcard = 1;
 921                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
 922                            ssid->ssid_len)
 923                         need_ssids++;
 924
 925 #ifdef CONFIG_WPS
 926                 if (!wpas_network_disabled(wpa_s, ssid) &&
 927                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
 928                         /*
 929                          * Normal scan is more reliable and faster for WPS
 930                          * operations and since these are for short periods of
 931                          * time, the benefit of trying to use sched_scan would
 932                          * be limited.
 933                          */
 934                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 935                                 "sched_scan for WPS");
 936                         return -1;
 937                 }
 938 #endif /* CONFIG_WPS */
 939         }
 940         if (wildcard)
 941                 need_ssids++;
 942
 943         if (wpa_s->normal_scans < 3 &&
 944             (need_ssids <= wpa_s->max_scan_ssids ||
 945              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
 946                 /*
 947                  * When normal scan can speed up operations, use that for the
 948                  * first operations before starting the sched_scan to allow
 949                  * user space sleep more. We do this only if the normal scan
 950                  * has functionality that is suitable for this or if the
 951                  * sched_scan does not have better support for multiple SSIDs.
 952                  */
 953                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 954                         "sched_scan for initial scans (normal_scans=%d)",
 955                         wpa_s->normal_scans);
 956                 return -1;
 957         }
 958
 959         os_memset(&params, 0, sizeof(params));
 960
 961         /* If we can't allocate space for the filters, we just don't filter */
 962         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
 963                                         sizeof(struct wpa_driver_scan_filter));
 964
 965         prev_state = wpa_s->wpa_state;
 966 #ifndef ANDROID_P2P
 967         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 968             wpa_s->wpa_state == WPA_INACTIVE)
 969                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 970 #endif
 971
 972         if (wpa_s->autoscan_params != NULL) {
 973                 scan_params = wpa_s->autoscan_params;
 974                 goto scan;
 975         }
 976
 977         /* Find the starting point from which to continue scanning */
 978         ssid = wpa_s->conf->ssid;
 979         if (wpa_s->prev_sched_ssid) {
 980                 while (ssid) {
 981                         if (ssid == wpa_s->prev_sched_ssid) {
 982                                 ssid = ssid->next;
 983                                 break;
 984                         }
 985                         ssid = ssid->next;
 986                 }
 987         }
 988
 989         if (!ssid || !wpa_s->prev_sched_ssid) {
 990                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
 991
 992                 if (wpa_s->sched_scan_interval == 0)
 993                         wpa_s->sched_scan_interval = 10;
 994                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
 995                 wpa_s->first_sched_scan = 1;
 996                 ssid = wpa_s->conf->ssid;
 997                 wpa_s->prev_sched_ssid = ssid;
 998         }
 999
1000         if (wildcard) {
1001                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1002                 params.num_ssids++;
1003         }
1004
1005         while (ssid) {
1006                 if (wpas_network_disabled(wpa_s, ssid))
1007                         goto next;
1008
1009                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
1010                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1011                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1012                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1013                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1014                                   ssid->ssid, ssid->ssid_len);
1015                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1016                                 ssid->ssid_len;
1017                         params.num_filter_ssids++;
1018                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1019                 {
1020                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1021                                 "filter for sched_scan - drop filter");
1022                         os_free(params.filter_ssids);
1023                         params.filter_ssids = NULL;
1024                         params.num_filter_ssids = 0;
1025                 }
1026
1027                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1028                         if (params.num_ssids == max_sched_scan_ssids)
1029                                 break; /* only room for broadcast SSID */
1030                         wpa_dbg(wpa_s, MSG_DEBUG,
1031                                 "add to active scan ssid: %s",
1032                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1033                         params.ssids[params.num_ssids].ssid =
1034                                 ssid->ssid;
1035                         params.ssids[params.num_ssids].ssid_len =
1036                                 ssid->ssid_len;
1037                         params.num_ssids++;
1038                         if (params.num_ssids >= max_sched_scan_ssids) {
1039                                 wpa_s->prev_sched_ssid = ssid;
1040                                 do {
1041                                         ssid = ssid->next;
1042                                 } while (ssid &&
1043                                          (wpas_network_disabled(wpa_s, ssid) ||
1044                                           !ssid->scan_ssid));
1045                                 break;
1046                         }
1047                 }
1048
1049         next:
1050                 wpa_s->prev_sched_ssid = ssid;
1051                 ssid = ssid->next;
1052         }
1053
1054         if (params.num_filter_ssids == 0) {
1055                 os_free(params.filter_ssids);
1056                 params.filter_ssids = NULL;
1057         }
1058
1059         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1060         if (extra_ie) {
1061                 params.extra_ies = wpabuf_head(extra_ie);
1062                 params.extra_ies_len = wpabuf_len(extra_ie);
1063         }
1064
1065         scan_params = &params;
1066
1067 scan:
1068         if (ssid || !wpa_s->first_sched_scan) {
1069                 wpa_dbg(wpa_s, MSG_DEBUG,
1070                         "Starting sched scan: interval %d timeout %d",
1071                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1072         } else {
1073                 wpa_dbg(wpa_s, MSG_DEBUG,
1074                         "Starting sched scan: interval %d (no timeout)",
1075                         wpa_s->sched_scan_interval);
1076         }
1077
1078         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1079                                               wpa_s->sched_scan_interval);
1080         wpabuf_free(extra_ie);
1081         os_free(params.filter_ssids);
1082         if (ret) {
1083                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1084                 if (prev_state != wpa_s->wpa_state)
1085                         wpa_supplicant_set_state(wpa_s, prev_state);
1086                 return ret;
1087         }
1088
1089         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1090         if (ssid || !wpa_s->first_sched_scan) {
1091                 wpa_s->sched_scan_timed_out = 0;
1092                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1093                                        wpa_supplicant_sched_scan_timeout,
1094                                        wpa_s, NULL);
1095                 wpa_s->first_sched_scan = 0;
1096                 wpa_s->sched_scan_timeout /= 2;
1097                 wpa_s->sched_scan_interval *= 2;
1098         }
1099
1100         return 0;
1101 }
1102
1103
1104 /**
1105  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1106  * @wpa_s: Pointer to wpa_supplicant data
1107  *
1108  * This function is used to cancel a scan request scheduled with
1109  * wpa_supplicant_req_scan().
1110  */
1111 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1112 {
1113         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1114         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1115 #ifdef ANDROID
1116         wpa_supplicant_notify_scanning(wpa_s, 0);
1117 #endif
1118 }
1119
1120
1121 /**
1122  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1123  * @wpa_s: Pointer to wpa_supplicant data
1124  *
1125  * This function is used to stop a periodic scheduled scan.
1126  */
1127 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1128 {
1129         if (!wpa_s->sched_scanning)
1130                 return;
1131
1132         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1133         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1134         wpa_supplicant_stop_sched_scan(wpa_s);
1135 }
1136
1137
1138 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1139                                     int scanning)
1140 {
1141         if (wpa_s->scanning != scanning) {
1142 #ifdef ANDROID_P2P
1143                 if(!wpa_s->sched_scanning)
1144                         wpa_s->scanning = scanning;
1145 #else
1146                 wpa_s->scanning = scanning;
1147 #endif
1148                 wpas_notify_scanning(wpa_s);
1149         }
1150 }
1151
1152
1153 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1154 {
1155         int rate = 0;
1156         const u8 *ie;
1157         int i;
1158
1159         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1160         for (i = 0; ie && i < ie[1]; i++) {
1161                 if ((ie[i + 2] & 0x7f) > rate)
1162                         rate = ie[i + 2] & 0x7f;
1163         }
1164
1165         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1166         for (i = 0; ie && i < ie[1]; i++) {
1167                 if ((ie[i + 2] & 0x7f) > rate)
1168                         rate = ie[i + 2] & 0x7f;
1169         }
1170
1171         return rate;
1172 }
1173
1174
1175 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1176 {
1177         const u8 *end, *pos;
1178
1179         pos = (const u8 *) (res + 1);
1180         end = pos + res->ie_len;
1181
1182         while (pos + 1 < end) {
1183                 if (pos + 2 + pos[1] > end)
1184                         break;
1185                 if (pos[0] == ie)
1186                         return pos;
1187                 pos += 2 + pos[1];
1188         }
1189
1190         return NULL;
1191 }
1192
1193
1194 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1195                                   u32 vendor_type)
1196 {
1197         const u8 *end, *pos;
1198
1199         pos = (const u8 *) (res + 1);
1200         end = pos + res->ie_len;
1201
1202         while (pos + 1 < end) {
1203                 if (pos + 2 + pos[1] > end)
1204                         break;
1205                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1206                     vendor_type == WPA_GET_BE32(&pos[2]))
1207                         return pos;
1208                 pos += 2 + pos[1];
1209         }
1210
1211         return NULL;
1212 }
1213
1214
1215 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1216                                              u32 vendor_type)
1217 {
1218         struct wpabuf *buf;
1219         const u8 *end, *pos;
1220
1221         buf = wpabuf_alloc(res->ie_len);
1222         if (buf == NULL)
1223                 return NULL;
1224
1225         pos = (const u8 *) (res + 1);
1226         end = pos + res->ie_len;
1227
1228         while (pos + 1 < end) {
1229                 if (pos + 2 + pos[1] > end)
1230                         break;
1231                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1232                     vendor_type == WPA_GET_BE32(&pos[2]))
1233                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1234                 pos += 2 + pos[1];
1235         }
1236
1237         if (wpabuf_len(buf) == 0) {
1238                 wpabuf_free(buf);
1239                 buf = NULL;
1240         }
1241
1242         return buf;
1243 }
1244
1245
1246 struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
1247         const struct wpa_scan_res *res, u32 vendor_type)
1248 {
1249         struct wpabuf *buf;
1250         const u8 *end, *pos;
1251
1252         if (res->beacon_ie_len == 0)
1253                 return NULL;
1254         buf = wpabuf_alloc(res->beacon_ie_len);
1255         if (buf == NULL)
1256                 return NULL;
1257
1258         pos = (const u8 *) (res + 1);
1259         pos += res->ie_len;
1260         end = pos + res->beacon_ie_len;
1261
1262         while (pos + 1 < end) {
1263                 if (pos + 2 + pos[1] > end)
1264                         break;
1265                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1266                     vendor_type == WPA_GET_BE32(&pos[2]))
1267                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1268                 pos += 2 + pos[1];
1269         }
1270
1271         if (wpabuf_len(buf) == 0) {
1272                 wpabuf_free(buf);
1273                 buf = NULL;
1274         }
1275
1276         return buf;
1277 }
1278
1279
1280 /*
1281  * Channels with a great SNR can operate at full rate. What is a great SNR?
1282  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1283  * rule of thumb is that any SNR above 20 is good." This one
1284  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1285  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1286  * conservative value.
1287  */
1288 #define GREAT_SNR 30
1289
1290 /* Compare function for sorting scan results. Return >0 if @b is considered
1291  * better. */
1292 static int wpa_scan_result_compar(const void *a, const void *b)
1293 {
1294 #define IS_5GHZ(n) (n > 4000)
1295 #define MIN(a,b) a < b ? a : b
1296         struct wpa_scan_res **_wa = (void *) a;
1297         struct wpa_scan_res **_wb = (void *) b;
1298         struct wpa_scan_res *wa = *_wa;
1299         struct wpa_scan_res *wb = *_wb;
1300         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1301         int snr_a, snr_b;
1302
1303         /* WPA/WPA2 support preferred */
1304         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1305                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1306         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1307                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1308
1309         if (wpa_b && !wpa_a)
1310                 return 1;
1311         if (!wpa_b && wpa_a)
1312                 return -1;
1313
1314         /* privacy support preferred */
1315         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1316             (wb->caps & IEEE80211_CAP_PRIVACY))
1317                 return 1;
1318         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1319             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1320                 return -1;
1321
1322         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1323             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1324                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1325                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1326         } else {
1327                 /* Not suitable information to calculate SNR, so use level */
1328                 snr_a = wa->level;
1329                 snr_b = wb->level;
1330         }
1331
1332         /* best/max rate preferred if SNR close enough */
1333         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1334             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1335                 maxrate_a = wpa_scan_get_max_rate(wa);
1336                 maxrate_b = wpa_scan_get_max_rate(wb);
1337                 if (maxrate_a != maxrate_b)
1338                         return maxrate_b - maxrate_a;
1339                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1340                         return IS_5GHZ(wa->freq) ? -1 : 1;
1341         }
1342
1343         /* use freq for channel preference */
1344
1345         /* all things being equal, use SNR; if SNRs are
1346          * identical, use quality values since some drivers may only report
1347          * that value and leave the signal level zero */
1348         if (snr_b == snr_a)
1349                 return wb->qual - wa->qual;
1350         return snr_b - snr_a;
1351 #undef MIN
1352 #undef IS_5GHZ
1353 }
1354
1355
1356 #ifdef CONFIG_WPS
1357 /* Compare function for sorting scan results when searching a WPS AP for
1358  * provisioning. Return >0 if @b is considered better. */
1359 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1360 {
1361         struct wpa_scan_res **_wa = (void *) a;
1362         struct wpa_scan_res **_wb = (void *) b;
1363         struct wpa_scan_res *wa = *_wa;
1364         struct wpa_scan_res *wb = *_wb;
1365         int uses_wps_a, uses_wps_b;
1366         struct wpabuf *wps_a, *wps_b;
1367         int res;
1368
1369         /* Optimization - check WPS IE existence before allocated memory and
1370          * doing full reassembly. */
1371         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1372         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1373         if (uses_wps_a && !uses_wps_b)
1374                 return -1;
1375         if (!uses_wps_a && uses_wps_b)
1376                 return 1;
1377
1378         if (uses_wps_a && uses_wps_b) {
1379                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1380                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1381                 res = wps_ap_priority_compar(wps_a, wps_b);
1382                 wpabuf_free(wps_a);
1383                 wpabuf_free(wps_b);
1384                 if (res)
1385                         return res;
1386         }
1387
1388         /*
1389          * Do not use current AP security policy as a sorting criteria during
1390          * WPS provisioning step since the AP may get reconfigured at the
1391          * completion of provisioning.
1392          */
1393
1394         /* all things being equal, use signal level; if signal levels are
1395          * identical, use quality values since some drivers may only report
1396          * that value and leave the signal level zero */
1397         if (wb->level == wa->level)
1398                 return wb->qual - wa->qual;
1399         return wb->level - wa->level;
1400 }
1401 #endif /* CONFIG_WPS */
1402
1403
1404 static void dump_scan_res(struct wpa_scan_results *scan_res)
1405 {
1406 #ifndef CONFIG_NO_STDOUT_DEBUG
1407         size_t i;
1408
1409         if (scan_res->res == NULL || scan_res->num == 0)
1410                 return;
1411
1412         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1413
1414         for (i = 0; i < scan_res->num; i++) {
1415                 struct wpa_scan_res *r = scan_res->res[i];
1416                 u8 *pos;
1417                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1418                     == WPA_SCAN_LEVEL_DBM) {
1419                         int snr = r->level - r->noise;
1420                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1421                                    "noise=%d level=%d snr=%d%s flags=0x%x",
1422                                    MAC2STR(r->bssid), r->freq, r->qual,
1423                                    r->noise, r->level, snr,
1424                                    snr >= GREAT_SNR ? "*" : "", r->flags);
1425                 } else {
1426                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1427                                    "noise=%d level=%d flags=0x%x",
1428                                    MAC2STR(r->bssid), r->freq, r->qual,
1429                                    r->noise, r->level, r->flags);
1430                 }
1431                 pos = (u8 *) (r + 1);
1432                 if (r->ie_len)
1433                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1434                 pos += r->ie_len;
1435                 if (r->beacon_ie_len)
1436                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1437                                     pos, r->beacon_ie_len);
1438         }
1439 #endif /* CONFIG_NO_STDOUT_DEBUG */
1440 }
1441
1442
1443 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1444                                       const u8 *bssid)
1445 {
1446         size_t i;
1447
1448         if (wpa_s->bssid_filter == NULL)
1449                 return 1;
1450
1451         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1452                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1453                               ETH_ALEN) == 0)
1454                         return 1;
1455         }
1456
1457         return 0;
1458 }
1459
1460
1461 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1462                             struct wpa_scan_results *res)
1463 {
1464         size_t i, j;
1465
1466         if (wpa_s->bssid_filter == NULL)
1467                 return;
1468
1469         for (i = 0, j = 0; i < res->num; i++) {
1470                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1471                                                       res->res[i]->bssid)) {
1472                         res->res[j++] = res->res[i];
1473                 } else {
1474                         os_free(res->res[i]);
1475                         res->res[i] = NULL;
1476                 }
1477         }
1478
1479         if (res->num != j) {
1480                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1481                            (int) (res->num - j));
1482                 res->num = j;
1483         }
1484 }
1485
1486
1487 /**
1488  * wpa_supplicant_get_scan_results - Get scan results
1489  * @wpa_s: Pointer to wpa_supplicant data
1490  * @info: Information about what was scanned or %NULL if not available
1491  * @new_scan: Whether a new scan was performed
1492  * Returns: Scan results, %NULL on failure
1493  *
1494  * This function request the current scan results from the driver and updates
1495  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1496  * results with wpa_scan_results_free().
1497  */
1498 struct wpa_scan_results *
1499 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1500                                 struct scan_info *info, int new_scan)
1501 {
1502         struct wpa_scan_results *scan_res;
1503         size_t i;
1504         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1505
1506         scan_res = wpa_drv_get_scan_results2(wpa_s);
1507         if (scan_res == NULL) {
1508                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1509                 return NULL;
1510         }
1511         filter_scan_res(wpa_s, scan_res);
1512
1513 #ifdef CONFIG_WPS
1514         if (wpas_wps_in_progress(wpa_s)) {
1515                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1516                         "provisioning rules");
1517                 compar = wpa_scan_result_wps_compar;
1518         }
1519 #endif /* CONFIG_WPS */
1520
1521         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1522               compar);
1523         dump_scan_res(scan_res);
1524
1525         wpa_bss_update_start(wpa_s);
1526         for (i = 0; i < scan_res->num; i++)
1527                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
1528         wpa_bss_update_end(wpa_s, info, new_scan);
1529
1530         return scan_res;
1531 }
1532
1533
1534 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1535 {
1536         struct wpa_scan_results *scan_res;
1537         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1538         if (scan_res == NULL)
1539                 return -1;
1540         wpa_scan_results_free(scan_res);
1541
1542         return 0;
1543 }