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
 253         wpa_supplicant_notify_scanning(wpa_s, 1);
 254         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 255         if (ret)
 256                 wpa_supplicant_notify_scanning(wpa_s, 0);
 257         else
 258                 wpa_s->sched_scanning = 1;
 259
 260         return ret;
 261 }
 262
 263
 264 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 265 {
 266         int ret;
 267
 268         ret = wpa_drv_stop_sched_scan(wpa_s);
 269         if (ret) {
 270                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 271                 /* TODO: what to do if stopping fails? */
 272                 return -1;
 273         }
 274
 275         return ret;
 276 }
 277
 278
 279 static struct wpa_driver_scan_filter *
 280 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 281 {
 282         struct wpa_driver_scan_filter *ssids;
 283         struct wpa_ssid *ssid;
 284         size_t count;
 285
 286         *num_ssids = 0;
 287         if (!conf->filter_ssids)
 288                 return NULL;
 289
 290         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 291                 if (ssid->ssid && ssid->ssid_len)
 292                         count++;
 293         }
 294         if (count == 0)
 295                 return NULL;
 296         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 297         if (ssids == NULL)
 298                 return NULL;
 299
 300         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 301                 if (!ssid->ssid || !ssid->ssid_len)
 302                         continue;
 303                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 304                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 305                 (*num_ssids)++;
 306         }
 307
 308         return ssids;
 309 }
 310
 311
 312 static void wpa_supplicant_optimize_freqs(
 313         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 314 {
 315 #ifdef CONFIG_P2P
 316         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 317             wpa_s->go_params) {
 318                 /* Optimize provisioning state scan based on GO information */
 319                 if (wpa_s->p2p_in_provisioning < 5 &&
 320                     wpa_s->go_params->freq > 0) {
 321                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 322                                 "preferred frequency %d MHz",
 323                                 wpa_s->go_params->freq);
 324                         params->freqs = os_zalloc(2 * sizeof(int));
 325                         if (params->freqs)
 326                                 params->freqs[0] = wpa_s->go_params->freq;
 327                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 328                            wpa_s->go_params->freq_list[0]) {
 329                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 330                                 "channels");
 331                         int_array_concat(&params->freqs,
 332                                          wpa_s->go_params->freq_list);
 333                         if (params->freqs)
 334                                 int_array_sort_unique(params->freqs);
 335                 }
 336                 wpa_s->p2p_in_provisioning++;
 337         }
 338 #endif /* CONFIG_P2P */
 339
 340 #ifdef CONFIG_WPS
 341         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 342                 /*
 343                  * Optimize post-provisioning scan based on channel used
 344                  * during provisioning.
 345                  */
 346                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 347                         "that was used during provisioning", wpa_s->wps_freq);
 348                 params->freqs = os_zalloc(2 * sizeof(int));
 349                 if (params->freqs)
 350                         params->freqs[0] = wpa_s->wps_freq;
 351                 wpa_s->after_wps--;
 352         }
 353
 354         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 355         {
 356                 /* Optimize provisioning scan based on already known channel */
 357                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 358                         wpa_s->wps_freq);
 359                 params->freqs = os_zalloc(2 * sizeof(int));
 360                 if (params->freqs)
 361                         params->freqs[0] = wpa_s->wps_freq;
 362                 wpa_s->known_wps_freq = 0; /* only do this once */
 363         }
 364 #endif /* CONFIG_WPS */
 365 }
 366
 367
 368 #ifdef CONFIG_INTERWORKING
 369 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 370                                            struct wpabuf *buf)
 371 {
 372         if (wpa_s->conf->interworking == 0)
 373                 return;
 374
 375         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 376         wpabuf_put_u8(buf, 4);
 377         wpabuf_put_u8(buf, 0x00);
 378         wpabuf_put_u8(buf, 0x00);
 379         wpabuf_put_u8(buf, 0x00);
 380         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 381
 382         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 383         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 384                       1 + ETH_ALEN);
 385         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 386         /* No Venue Info */
 387         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 388                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 389 }
 390 #endif /* CONFIG_INTERWORKING */
 391
 392
 393 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
 394 {
 395         struct wpabuf *extra_ie = NULL;
 396 #ifdef CONFIG_WPS
 397         int wps = 0;
 398         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 399 #endif /* CONFIG_WPS */
 400
 401 #ifdef CONFIG_INTERWORKING
 402         if (wpa_s->conf->interworking &&
 403             wpabuf_resize(&extra_ie, 100) == 0)
 404                 wpas_add_interworking_elements(wpa_s, extra_ie);
 405 #endif /* CONFIG_INTERWORKING */
 406
 407 #ifdef CONFIG_WPS
 408         wps = wpas_wps_in_use(wpa_s, &req_type);
 409
 410         if (wps) {
 411                 struct wpabuf *wps_ie;
 412                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
 413                                                 DEV_PW_DEFAULT,
 414                                                 &wpa_s->wps->dev,
 415                                                 wpa_s->wps->uuid, req_type,
 416                                                 0, NULL);
 417                 if (wps_ie) {
 418                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 419                                 wpabuf_put_buf(extra_ie, wps_ie);
 420                         wpabuf_free(wps_ie);
 421                 }
 422         }
 423
 424 #ifdef CONFIG_P2P
 425         if (wps) {
 426                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 427                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 428                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 429         }
 430 #endif /* CONFIG_P2P */
 431
 432 #endif /* CONFIG_WPS */
 433
 434         return extra_ie;
 435 }
 436
 437
 438 #ifdef CONFIG_P2P
 439
 440 /*
 441  * Check whether there are any enabled networks or credentials that could be
 442  * used for a non-P2P connection.
 443  */
 444 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
 445 {
 446         struct wpa_ssid *ssid;
 447
 448         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 449                 if (wpas_network_disabled(wpa_s, ssid))
 450                         continue;
 451                 if (!ssid->p2p_group)
 452                         return 1;
 453         }
 454
 455         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
 456             wpa_s->conf->auto_interworking)
 457                 return 1;
 458
 459         return 0;
 460 }
 461
 462
 463 /*
 464  * Find the operating frequency of any other virtual interface that is using
 465  * the same radio concurrently.
 466  */
 467 static int shared_vif_oper_freq(struct wpa_supplicant *wpa_s)
 468 {
 469         const char *rn, *rn2;
 470         struct wpa_supplicant *ifs;
 471         u8 bssid[ETH_ALEN];
 472
 473         if (!wpa_s->driver->get_radio_name)
 474                 return -1;
 475
 476         rn = wpa_s->driver->get_radio_name(wpa_s->drv_priv);
 477         if (rn == NULL || rn[0] == '\0')
 478                 return -1;
 479
 480         for (ifs = wpa_s->global->ifaces; ifs; ifs = ifs->next) {
 481                 if (ifs == wpa_s || !ifs->driver->get_radio_name)
 482                         continue;
 483
 484                 rn2 = ifs->driver->get_radio_name(ifs->drv_priv);
 485                 if (!rn2 || os_strcmp(rn, rn2) != 0)
 486                         continue;
 487
 488                 if (ifs->current_ssid == NULL || ifs->assoc_freq == 0)
 489                         continue;
 490
 491                 if (ifs->current_ssid->mode == WPAS_MODE_AP ||
 492                     ifs->current_ssid->mode == WPAS_MODE_P2P_GO)
 493                         return ifs->current_ssid->frequency;
 494                 if (wpa_drv_get_bssid(ifs, bssid) == 0)
 495                         return ifs->assoc_freq;
 496         }
 497
 498         return 0;
 499 }
 500
 501 #endif /* CONFIG_P2P */
 502
 503
 504 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 505 {
 506         struct wpa_supplicant *wpa_s = eloop_ctx;
 507         struct wpa_ssid *ssid;
 508         enum scan_req_type scan_req = NORMAL_SCAN_REQ;
 509         int ret;
 510         struct wpabuf *extra_ie = NULL;
 511         struct wpa_driver_scan_params params;
 512         struct wpa_driver_scan_params *scan_params;
 513         size_t max_ssids;
 514         enum wpa_states prev_state;
 515
 516         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 517                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 518                 return;
 519         }
 520
 521         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
 522                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
 523                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 524                 return;
 525         }
 526
 527         if (!wpa_supplicant_enabled_networks(wpa_s) &&
 528             wpa_s->scan_req == NORMAL_SCAN_REQ) {
 529                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 530                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 531 #ifdef CONFIG_P2P
 532                 wpa_s->sta_scan_pending = 0;
 533 #endif /* CONFIG_P2P */
 534                 return;
 535         }
 536
 537         if (wpa_s->conf->ap_scan != 0 &&
 538             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 539                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 540                         "overriding ap_scan configuration");
 541                 wpa_s->conf->ap_scan = 0;
 542                 wpas_notify_ap_scan_changed(wpa_s);
 543         }
 544
 545         if (wpa_s->conf->ap_scan == 0) {
 546                 wpa_supplicant_gen_assoc_event(wpa_s);
 547                 return;
 548         }
 549
 550 #ifdef CONFIG_P2P
 551         if (wpas_p2p_in_progress(wpa_s)) {
 552                 if (wpa_s->sta_scan_pending &&
 553                     wpas_p2p_in_progress(wpa_s) == 2 &&
 554                     wpa_s->global->p2p_cb_on_scan_complete) {
 555                         wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
 556                                 "mode scan during P2P search");
 557                 } else {
 558                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 559                                 "while P2P operation is in progress");
 560                         wpa_s->sta_scan_pending = 1;
 561                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 562                         return;
 563                 }
 564         }
 565 #endif /* CONFIG_P2P */
 566
 567         if (wpa_s->conf->ap_scan == 2)
 568                 max_ssids = 1;
 569         else {
 570                 max_ssids = wpa_s->max_scan_ssids;
 571                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 572                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 573         }
 574
 575         scan_req = wpa_s->scan_req;
 576         wpa_s->scan_req = NORMAL_SCAN_REQ;
 577
 578         os_memset(&params, 0, sizeof(params));
 579
 580         prev_state = wpa_s->wpa_state;
 581         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 582             wpa_s->wpa_state == WPA_INACTIVE)
 583                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 584
 585         /*
 586          * If autoscan has set its own scanning parameters
 587          */
 588         if (wpa_s->autoscan_params != NULL) {
 589                 scan_params = wpa_s->autoscan_params;
 590                 goto scan;
 591         }
 592
 593         if (scan_req != MANUAL_SCAN_REQ && wpa_s->connect_without_scan) {
 594                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 595                         if (ssid == wpa_s->connect_without_scan)
 596                                 break;
 597                 }
 598                 wpa_s->connect_without_scan = NULL;
 599                 if (ssid) {
 600                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 601                                    "without scan step");
 602                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 603                         return;
 604                 }
 605         }
 606
 607 #ifdef CONFIG_P2P
 608         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
 609             wpa_s->go_params) {
 610                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during "
 611                            "P2P group formation");
 612                 params.ssids[0].ssid = wpa_s->go_params->ssid;
 613                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
 614                 params.num_ssids = 1;
 615                 goto ssid_list_set;
 616         }
 617 #endif /* CONFIG_P2P */
 618
 619         /* Find the starting point from which to continue scanning */
 620         ssid = wpa_s->conf->ssid;
 621         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 622                 while (ssid) {
 623                         if (ssid == wpa_s->prev_scan_ssid) {
 624                                 ssid = ssid->next;
 625                                 break;
 626                         }
 627                         ssid = ssid->next;
 628                 }
 629         }
 630
 631         if (scan_req != MANUAL_SCAN_REQ && wpa_s->conf->ap_scan == 2) {
 632                 wpa_s->connect_without_scan = NULL;
 633                 wpa_s->prev_scan_wildcard = 0;
 634                 wpa_supplicant_assoc_try(wpa_s, ssid);
 635                 return;
 636         } else if (wpa_s->conf->ap_scan == 2) {
 637                 /*
 638                  * User-initiated scan request in ap_scan == 2; scan with
 639                  * wildcard SSID.
 640                  */
 641                 ssid = NULL;
 642         } else {
 643                 struct wpa_ssid *start = ssid, *tssid;
 644                 int freqs_set = 0;
 645                 if (ssid == NULL && max_ssids > 1)
 646                         ssid = wpa_s->conf->ssid;
 647                 while (ssid) {
 648                         if (!wpas_network_disabled(wpa_s, ssid) &&
 649                             ssid->scan_ssid) {
 650                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 651                                                   ssid->ssid, ssid->ssid_len);
 652                                 params.ssids[params.num_ssids].ssid =
 653                                         ssid->ssid;
 654                                 params.ssids[params.num_ssids].ssid_len =
 655                                         ssid->ssid_len;
 656                                 params.num_ssids++;
 657                                 if (params.num_ssids + 1 >= max_ssids)
 658                                         break;
 659                         }
 660                         ssid = ssid->next;
 661                         if (ssid == start)
 662                                 break;
 663                         if (ssid == NULL && max_ssids > 1 &&
 664                             start != wpa_s->conf->ssid)
 665                                 ssid = wpa_s->conf->ssid;
 666                 }
 667
 668                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 669                         if (wpas_network_disabled(wpa_s, tssid))
 670                                 continue;
 671                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 672                                 int_array_concat(&params.freqs,
 673                                                  tssid->scan_freq);
 674                         } else {
 675                                 os_free(params.freqs);
 676                                 params.freqs = NULL;
 677                         }
 678                         freqs_set = 1;
 679                 }
 680                 int_array_sort_unique(params.freqs);
 681         }
 682
 683         if (ssid && max_ssids == 1) {
 684                 /*
 685                  * If the driver is limited to 1 SSID at a time interleave
 686                  * wildcard SSID scans with specific SSID scans to avoid
 687                  * waiting a long time for a wildcard scan.
 688                  */
 689                 if (!wpa_s->prev_scan_wildcard) {
 690                         params.ssids[0].ssid = NULL;
 691                         params.ssids[0].ssid_len = 0;
 692                         wpa_s->prev_scan_wildcard = 1;
 693                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 694                                 "wildcard SSID (Interleave with specific)");
 695                 } else {
 696                         wpa_s->prev_scan_ssid = ssid;
 697                         wpa_s->prev_scan_wildcard = 0;
 698                         wpa_dbg(wpa_s, MSG_DEBUG,
 699                                 "Starting AP scan for specific SSID: %s",
 700                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 701                 }
 702         } else if (ssid) {
 703                 /* max_ssids > 1 */
 704
 705                 wpa_s->prev_scan_ssid = ssid;
 706                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 707                         "the scan request");
 708                 params.num_ssids++;
 709         } else {
 710                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 711                 params.num_ssids++;
 712                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 713                         "SSID");
 714         }
 715 #ifdef CONFIG_P2P
 716 ssid_list_set:
 717 #endif /* CONFIG_P2P */
 718
 719         wpa_supplicant_optimize_freqs(wpa_s, &params);
 720         extra_ie = wpa_supplicant_extra_ies(wpa_s);
 721
 722 #ifdef CONFIG_HS20
 723         if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 6) == 0)
 724                 wpas_hs20_add_indication(extra_ie);
 725 #endif /* CONFIG_HS20 */
 726
 727         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 728                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 729                         "generated frequency list");
 730                 params.freqs = wpa_s->next_scan_freqs;
 731         } else
 732                 os_free(wpa_s->next_scan_freqs);
 733         wpa_s->next_scan_freqs = NULL;
 734
 735         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 736                 wpa_s->conf, &params.num_filter_ssids);
 737         if (extra_ie) {
 738                 params.extra_ies = wpabuf_head(extra_ie);
 739                 params.extra_ies_len = wpabuf_len(extra_ie);
 740         }
 741
 742 #ifdef CONFIG_P2P
 743         if (wpa_s->p2p_in_provisioning ||
 744             (wpa_s->show_group_started && wpa_s->go_params)) {
 745                 /*
 746                  * The interface may not yet be in P2P mode, so we have to
 747                  * explicitly request P2P probe to disable CCK rates.
 748                  */
 749                 params.p2p_probe = 1;
 750         }
 751 #endif /* CONFIG_P2P */
 752
 753         scan_params = &params;
 754
 755 scan:
 756 #ifdef CONFIG_P2P
 757         /*
 758          * If the driver does not support multi-channel concurrency and a
 759          * virtual interface that shares the same radio with the wpa_s interface
 760          * is operating there may not be need to scan other channels apart from
 761          * the current operating channel on the other virtual interface. Filter
 762          * out other channels in case we are trying to find a connection for a
 763          * station interface when we are not configured to prefer station
 764          * connection and a concurrent operation is already in process.
 765          */
 766         if (wpa_s->scan_for_connection && scan_req == NORMAL_SCAN_REQ &&
 767             !scan_params->freqs && !params.freqs &&
 768             wpas_is_p2p_prioritized(wpa_s) &&
 769             !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_MULTI_CHANNEL_CONCURRENT) &&
 770             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
 771             non_p2p_network_enabled(wpa_s)) {
 772                 int freq = shared_vif_oper_freq(wpa_s);
 773                 if (freq > 0) {
 774                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only the current "
 775                                 "operating channel (%d MHz) since driver does "
 776                                 "not support multi-channel concurrency", freq);
 777                         params.freqs = os_zalloc(sizeof(int) * 2);
 778                         if (params.freqs)
 779                                 params.freqs[0] = freq;
 780                         scan_params->freqs = params.freqs;
 781                 }
 782         }
 783 #endif /* CONFIG_P2P */
 784
 785         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
 786
 787         wpabuf_free(extra_ie);
 788         os_free(params.freqs);
 789         os_free(params.filter_ssids);
 790
 791         if (ret) {
 792                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 793                 if (prev_state != wpa_s->wpa_state)
 794                         wpa_supplicant_set_state(wpa_s, prev_state);
 795                 /* Restore scan_req since we will try to scan again */
 796                 wpa_s->scan_req = scan_req;
 797                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 798         } else {
 799                 wpa_s->scan_for_connection = 0;
 800         }
 801 }
 802
 803
 804 /**
 805  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 806  * @wpa_s: Pointer to wpa_supplicant data
 807  * @sec: Number of seconds after which to scan
 808  * @usec: Number of microseconds after which to scan
 809  *
 810  * This function is used to schedule a scan for neighboring access points after
 811  * the specified time.
 812  */
 813 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 814 {
 815         /* If there's at least one network that should be specifically scanned
 816          * then don't cancel the scan and reschedule.  Some drivers do
 817          * background scanning which generates frequent scan results, and that
 818          * causes the specific SSID scan to get continually pushed back and
 819          * never happen, which causes hidden APs to never get probe-scanned.
 820          */
 821         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 822             wpa_s->conf->ap_scan == 1) {
 823                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 824
 825                 while (ssid) {
 826                         if (!wpas_network_disabled(wpa_s, ssid) &&
 827                             ssid->scan_ssid)
 828                                 break;
 829                         ssid = ssid->next;
 830                 }
 831                 if (ssid) {
 832                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 833                                 "ensure that specific SSID scans occur");
 834                         return;
 835                 }
 836         }
 837
 838         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 839                 sec, usec);
 840         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 841         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 842 }
 843
 844
 845 /**
 846  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 847  * @wpa_s: Pointer to wpa_supplicant data
 848  * @sec: Number of seconds after which to scan
 849  * @usec: Number of microseconds after which to scan
 850  *
 851  * This function is used to schedule periodic scans for neighboring
 852  * access points after the specified time.
 853  */
 854 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 855                                       int sec, int usec)
 856 {
 857         if (!wpa_s->sched_scan_supported)
 858                 return -1;
 859
 860         eloop_register_timeout(sec, usec,
 861                                wpa_supplicant_delayed_sched_scan_timeout,
 862                                wpa_s, NULL);
 863
 864         return 0;
 865 }
 866
 867
 868 /**
 869  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 870  * @wpa_s: Pointer to wpa_supplicant data
 871  *
 872  * This function is used to schedule periodic scans for neighboring
 873  * access points repeating the scan continuously.
 874  */
 875 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 876 {
 877         struct wpa_driver_scan_params params;
 878         struct wpa_driver_scan_params *scan_params;
 879         enum wpa_states prev_state;
 880         struct wpa_ssid *ssid = NULL;
 881         struct wpabuf *extra_ie = NULL;
 882         int ret;
 883         unsigned int max_sched_scan_ssids;
 884         int wildcard = 0;
 885         int need_ssids;
 886
 887         if (!wpa_s->sched_scan_supported)
 888                 return -1;
 889
 890         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 891                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 892         else
 893                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 894         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
 895                 return -1;
 896
 897         if (wpa_s->sched_scanning) {
 898                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 899                 return 0;
 900         }
 901
 902         need_ssids = 0;
 903         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 904                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
 905                         /* Use wildcard SSID to find this network */
 906                         wildcard = 1;
 907                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
 908                            ssid->ssid_len)
 909                         need_ssids++;
 910
 911 #ifdef CONFIG_WPS
 912                 if (!wpas_network_disabled(wpa_s, ssid) &&
 913                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
 914                         /*
 915                          * Normal scan is more reliable and faster for WPS
 916                          * operations and since these are for short periods of
 917                          * time, the benefit of trying to use sched_scan would
 918                          * be limited.
 919                          */
 920                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 921                                 "sched_scan for WPS");
 922                         return -1;
 923                 }
 924 #endif /* CONFIG_WPS */
 925         }
 926         if (wildcard)
 927                 need_ssids++;
 928
 929         if (wpa_s->normal_scans < 3 &&
 930             (need_ssids <= wpa_s->max_scan_ssids ||
 931              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
 932                 /*
 933                  * When normal scan can speed up operations, use that for the
 934                  * first operations before starting the sched_scan to allow
 935                  * user space sleep more. We do this only if the normal scan
 936                  * has functionality that is suitable for this or if the
 937                  * sched_scan does not have better support for multiple SSIDs.
 938                  */
 939                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 940                         "sched_scan for initial scans (normal_scans=%d)",
 941                         wpa_s->normal_scans);
 942                 return -1;
 943         }
 944
 945         os_memset(&params, 0, sizeof(params));
 946
 947         /* If we can't allocate space for the filters, we just don't filter */
 948         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
 949                                         sizeof(struct wpa_driver_scan_filter));
 950
 951         prev_state = wpa_s->wpa_state;
 952         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 953             wpa_s->wpa_state == WPA_INACTIVE)
 954                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 955
 956         if (wpa_s->autoscan_params != NULL) {
 957                 scan_params = wpa_s->autoscan_params;
 958                 goto scan;
 959         }
 960
 961         /* Find the starting point from which to continue scanning */
 962         ssid = wpa_s->conf->ssid;
 963         if (wpa_s->prev_sched_ssid) {
 964                 while (ssid) {
 965                         if (ssid == wpa_s->prev_sched_ssid) {
 966                                 ssid = ssid->next;
 967                                 break;
 968                         }
 969                         ssid = ssid->next;
 970                 }
 971         }
 972
 973         if (!ssid || !wpa_s->prev_sched_ssid) {
 974                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
 975
 976                 if (wpa_s->sched_scan_interval == 0)
 977                         wpa_s->sched_scan_interval = 10;
 978                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
 979                 wpa_s->first_sched_scan = 1;
 980                 ssid = wpa_s->conf->ssid;
 981                 wpa_s->prev_sched_ssid = ssid;
 982         }
 983
 984         if (wildcard) {
 985                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
 986                 params.num_ssids++;
 987         }
 988
 989         while (ssid) {
 990                 if (wpas_network_disabled(wpa_s, ssid))
 991                         goto next;
 992
 993                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
 994                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
 995                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
 996                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 997                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
 998                                   ssid->ssid, ssid->ssid_len);
 999                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1000                                 ssid->ssid_len;
1001                         params.num_filter_ssids++;
1002                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1003                 {
1004                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1005                                 "filter for sched_scan - drop filter");
1006                         os_free(params.filter_ssids);
1007                         params.filter_ssids = NULL;
1008                         params.num_filter_ssids = 0;
1009                 }
1010
1011                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1012                         if (params.num_ssids == max_sched_scan_ssids)
1013                                 break; /* only room for broadcast SSID */
1014                         wpa_dbg(wpa_s, MSG_DEBUG,
1015                                 "add to active scan ssid: %s",
1016                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1017                         params.ssids[params.num_ssids].ssid =
1018                                 ssid->ssid;
1019                         params.ssids[params.num_ssids].ssid_len =
1020                                 ssid->ssid_len;
1021                         params.num_ssids++;
1022                         if (params.num_ssids >= max_sched_scan_ssids) {
1023                                 wpa_s->prev_sched_ssid = ssid;
1024                                 do {
1025                                         ssid = ssid->next;
1026                                 } while (ssid &&
1027                                          (wpas_network_disabled(wpa_s, ssid) ||
1028                                           !ssid->scan_ssid));
1029                                 break;
1030                         }
1031                 }
1032
1033         next:
1034                 wpa_s->prev_sched_ssid = ssid;
1035                 ssid = ssid->next;
1036         }
1037
1038         if (params.num_filter_ssids == 0) {
1039                 os_free(params.filter_ssids);
1040                 params.filter_ssids = NULL;
1041         }
1042
1043         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1044         if (extra_ie) {
1045                 params.extra_ies = wpabuf_head(extra_ie);
1046                 params.extra_ies_len = wpabuf_len(extra_ie);
1047         }
1048
1049         scan_params = &params;
1050
1051 scan:
1052         if (ssid || !wpa_s->first_sched_scan) {
1053                 wpa_dbg(wpa_s, MSG_DEBUG,
1054                         "Starting sched scan: interval %d timeout %d",
1055                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1056         } else {
1057                 wpa_dbg(wpa_s, MSG_DEBUG,
1058                         "Starting sched scan: interval %d (no timeout)",
1059                         wpa_s->sched_scan_interval);
1060         }
1061
1062         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1063                                               wpa_s->sched_scan_interval);
1064         wpabuf_free(extra_ie);
1065         os_free(params.filter_ssids);
1066         if (ret) {
1067                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1068                 if (prev_state != wpa_s->wpa_state)
1069                         wpa_supplicant_set_state(wpa_s, prev_state);
1070                 return ret;
1071         }
1072
1073         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1074         if (ssid || !wpa_s->first_sched_scan) {
1075                 wpa_s->sched_scan_timed_out = 0;
1076                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1077                                        wpa_supplicant_sched_scan_timeout,
1078                                        wpa_s, NULL);
1079                 wpa_s->first_sched_scan = 0;
1080                 wpa_s->sched_scan_timeout /= 2;
1081                 wpa_s->sched_scan_interval *= 2;
1082         }
1083
1084         return 0;
1085 }
1086
1087
1088 /**
1089  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1090  * @wpa_s: Pointer to wpa_supplicant data
1091  *
1092  * This function is used to cancel a scan request scheduled with
1093  * wpa_supplicant_req_scan().
1094  */
1095 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1096 {
1097         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1098         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1099 }
1100
1101
1102 /**
1103  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1104  * @wpa_s: Pointer to wpa_supplicant data
1105  *
1106  * This function is used to stop a periodic scheduled scan.
1107  */
1108 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1109 {
1110         if (!wpa_s->sched_scanning)
1111                 return;
1112
1113         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1114         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1115         wpa_supplicant_stop_sched_scan(wpa_s);
1116 }
1117
1118
1119 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1120                                     int scanning)
1121 {
1122         if (wpa_s->scanning != scanning) {
1123                 wpa_s->scanning = scanning;
1124                 wpas_notify_scanning(wpa_s);
1125         }
1126 }
1127
1128
1129 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1130 {
1131         int rate = 0;
1132         const u8 *ie;
1133         int i;
1134
1135         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1136         for (i = 0; ie && i < ie[1]; i++) {
1137                 if ((ie[i + 2] & 0x7f) > rate)
1138                         rate = ie[i + 2] & 0x7f;
1139         }
1140
1141         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1142         for (i = 0; ie && i < ie[1]; i++) {
1143                 if ((ie[i + 2] & 0x7f) > rate)
1144                         rate = ie[i + 2] & 0x7f;
1145         }
1146
1147         return rate;
1148 }
1149
1150
1151 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1152 {
1153         const u8 *end, *pos;
1154
1155         pos = (const u8 *) (res + 1);
1156         end = pos + res->ie_len;
1157
1158         while (pos + 1 < end) {
1159                 if (pos + 2 + pos[1] > end)
1160                         break;
1161                 if (pos[0] == ie)
1162                         return pos;
1163                 pos += 2 + pos[1];
1164         }
1165
1166         return NULL;
1167 }
1168
1169
1170 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1171                                   u32 vendor_type)
1172 {
1173         const u8 *end, *pos;
1174
1175         pos = (const u8 *) (res + 1);
1176         end = pos + res->ie_len;
1177
1178         while (pos + 1 < end) {
1179                 if (pos + 2 + pos[1] > end)
1180                         break;
1181                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1182                     vendor_type == WPA_GET_BE32(&pos[2]))
1183                         return pos;
1184                 pos += 2 + pos[1];
1185         }
1186
1187         return NULL;
1188 }
1189
1190
1191 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1192                                              u32 vendor_type)
1193 {
1194         struct wpabuf *buf;
1195         const u8 *end, *pos;
1196
1197         buf = wpabuf_alloc(res->ie_len);
1198         if (buf == NULL)
1199                 return NULL;
1200
1201         pos = (const u8 *) (res + 1);
1202         end = pos + res->ie_len;
1203
1204         while (pos + 1 < end) {
1205                 if (pos + 2 + pos[1] > end)
1206                         break;
1207                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1208                     vendor_type == WPA_GET_BE32(&pos[2]))
1209                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1210                 pos += 2 + pos[1];
1211         }
1212
1213         if (wpabuf_len(buf) == 0) {
1214                 wpabuf_free(buf);
1215                 buf = NULL;
1216         }
1217
1218         return buf;
1219 }
1220
1221
1222 struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
1223         const struct wpa_scan_res *res, u32 vendor_type)
1224 {
1225         struct wpabuf *buf;
1226         const u8 *end, *pos;
1227
1228         if (res->beacon_ie_len == 0)
1229                 return NULL;
1230         buf = wpabuf_alloc(res->beacon_ie_len);
1231         if (buf == NULL)
1232                 return NULL;
1233
1234         pos = (const u8 *) (res + 1);
1235         pos += res->ie_len;
1236         end = pos + res->beacon_ie_len;
1237
1238         while (pos + 1 < end) {
1239                 if (pos + 2 + pos[1] > end)
1240                         break;
1241                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1242                     vendor_type == WPA_GET_BE32(&pos[2]))
1243                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1244                 pos += 2 + pos[1];
1245         }
1246
1247         if (wpabuf_len(buf) == 0) {
1248                 wpabuf_free(buf);
1249                 buf = NULL;
1250         }
1251
1252         return buf;
1253 }
1254
1255
1256 /*
1257  * Channels with a great SNR can operate at full rate. What is a great SNR?
1258  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1259  * rule of thumb is that any SNR above 20 is good." This one
1260  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1261  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1262  * conservative value.
1263  */
1264 #define GREAT_SNR 30
1265
1266 /* Compare function for sorting scan results. Return >0 if @b is considered
1267  * better. */
1268 static int wpa_scan_result_compar(const void *a, const void *b)
1269 {
1270 #define IS_5GHZ(n) (n > 4000)
1271 #define MIN(a,b) a < b ? a : b
1272         struct wpa_scan_res **_wa = (void *) a;
1273         struct wpa_scan_res **_wb = (void *) b;
1274         struct wpa_scan_res *wa = *_wa;
1275         struct wpa_scan_res *wb = *_wb;
1276         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1277         int snr_a, snr_b;
1278
1279         /* WPA/WPA2 support preferred */
1280         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1281                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1282         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1283                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1284
1285         if (wpa_b && !wpa_a)
1286                 return 1;
1287         if (!wpa_b && wpa_a)
1288                 return -1;
1289
1290         /* privacy support preferred */
1291         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1292             (wb->caps & IEEE80211_CAP_PRIVACY))
1293                 return 1;
1294         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1295             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1296                 return -1;
1297
1298         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1299             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1300                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1301                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1302         } else {
1303                 /* Not suitable information to calculate SNR, so use level */
1304                 snr_a = wa->level;
1305                 snr_b = wb->level;
1306         }
1307
1308         /* best/max rate preferred if SNR close enough */
1309         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1310             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1311                 maxrate_a = wpa_scan_get_max_rate(wa);
1312                 maxrate_b = wpa_scan_get_max_rate(wb);
1313                 if (maxrate_a != maxrate_b)
1314                         return maxrate_b - maxrate_a;
1315                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1316                         return IS_5GHZ(wa->freq) ? -1 : 1;
1317         }
1318
1319         /* use freq for channel preference */
1320
1321         /* all things being equal, use SNR; if SNRs are
1322          * identical, use quality values since some drivers may only report
1323          * that value and leave the signal level zero */
1324         if (snr_b == snr_a)
1325                 return wb->qual - wa->qual;
1326         return snr_b - snr_a;
1327 #undef MIN
1328 #undef IS_5GHZ
1329 }
1330
1331
1332 #ifdef CONFIG_WPS
1333 /* Compare function for sorting scan results when searching a WPS AP for
1334  * provisioning. Return >0 if @b is considered better. */
1335 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1336 {
1337         struct wpa_scan_res **_wa = (void *) a;
1338         struct wpa_scan_res **_wb = (void *) b;
1339         struct wpa_scan_res *wa = *_wa;
1340         struct wpa_scan_res *wb = *_wb;
1341         int uses_wps_a, uses_wps_b;
1342         struct wpabuf *wps_a, *wps_b;
1343         int res;
1344
1345         /* Optimization - check WPS IE existence before allocated memory and
1346          * doing full reassembly. */
1347         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1348         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1349         if (uses_wps_a && !uses_wps_b)
1350                 return -1;
1351         if (!uses_wps_a && uses_wps_b)
1352                 return 1;
1353
1354         if (uses_wps_a && uses_wps_b) {
1355                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1356                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1357                 res = wps_ap_priority_compar(wps_a, wps_b);
1358                 wpabuf_free(wps_a);
1359                 wpabuf_free(wps_b);
1360                 if (res)
1361                         return res;
1362         }
1363
1364         /*
1365          * Do not use current AP security policy as a sorting criteria during
1366          * WPS provisioning step since the AP may get reconfigured at the
1367          * completion of provisioning.
1368          */
1369
1370         /* all things being equal, use signal level; if signal levels are
1371          * identical, use quality values since some drivers may only report
1372          * that value and leave the signal level zero */
1373         if (wb->level == wa->level)
1374                 return wb->qual - wa->qual;
1375         return wb->level - wa->level;
1376 }
1377 #endif /* CONFIG_WPS */
1378
1379
1380 static void dump_scan_res(struct wpa_scan_results *scan_res)
1381 {
1382 #ifndef CONFIG_NO_STDOUT_DEBUG
1383         size_t i;
1384
1385         if (scan_res->res == NULL || scan_res->num == 0)
1386                 return;
1387
1388         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1389
1390         for (i = 0; i < scan_res->num; i++) {
1391                 struct wpa_scan_res *r = scan_res->res[i];
1392                 u8 *pos;
1393                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1394                     == WPA_SCAN_LEVEL_DBM) {
1395                         int snr = r->level - r->noise;
1396                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1397                                    "noise=%d level=%d snr=%d%s flags=0x%x",
1398                                    MAC2STR(r->bssid), r->freq, r->qual,
1399                                    r->noise, r->level, snr,
1400                                    snr >= GREAT_SNR ? "*" : "", r->flags);
1401                 } else {
1402                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1403                                    "noise=%d level=%d flags=0x%x",
1404                                    MAC2STR(r->bssid), r->freq, r->qual,
1405                                    r->noise, r->level, r->flags);
1406                 }
1407                 pos = (u8 *) (r + 1);
1408                 if (r->ie_len)
1409                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1410                 pos += r->ie_len;
1411                 if (r->beacon_ie_len)
1412                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1413                                     pos, r->beacon_ie_len);
1414         }
1415 #endif /* CONFIG_NO_STDOUT_DEBUG */
1416 }
1417
1418
1419 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1420                                       const u8 *bssid)
1421 {
1422         size_t i;
1423
1424         if (wpa_s->bssid_filter == NULL)
1425                 return 1;
1426
1427         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1428                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1429                               ETH_ALEN) == 0)
1430                         return 1;
1431         }
1432
1433         return 0;
1434 }
1435
1436
1437 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1438                             struct wpa_scan_results *res)
1439 {
1440         size_t i, j;
1441
1442         if (wpa_s->bssid_filter == NULL)
1443                 return;
1444
1445         for (i = 0, j = 0; i < res->num; i++) {
1446                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1447                                                       res->res[i]->bssid)) {
1448                         res->res[j++] = res->res[i];
1449                 } else {
1450                         os_free(res->res[i]);
1451                         res->res[i] = NULL;
1452                 }
1453         }
1454
1455         if (res->num != j) {
1456                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1457                            (int) (res->num - j));
1458                 res->num = j;
1459         }
1460 }
1461
1462
1463 /**
1464  * wpa_supplicant_get_scan_results - Get scan results
1465  * @wpa_s: Pointer to wpa_supplicant data
1466  * @info: Information about what was scanned or %NULL if not available
1467  * @new_scan: Whether a new scan was performed
1468  * Returns: Scan results, %NULL on failure
1469  *
1470  * This function request the current scan results from the driver and updates
1471  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1472  * results with wpa_scan_results_free().
1473  */
1474 struct wpa_scan_results *
1475 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1476                                 struct scan_info *info, int new_scan)
1477 {
1478         struct wpa_scan_results *scan_res;
1479         size_t i;
1480         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1481
1482         scan_res = wpa_drv_get_scan_results2(wpa_s);
1483         if (scan_res == NULL) {
1484                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1485                 return NULL;
1486         }
1487         filter_scan_res(wpa_s, scan_res);
1488
1489 #ifdef CONFIG_WPS
1490         if (wpas_wps_in_progress(wpa_s)) {
1491                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1492                         "provisioning rules");
1493                 compar = wpa_scan_result_wps_compar;
1494         }
1495 #endif /* CONFIG_WPS */
1496
1497         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1498               compar);
1499         dump_scan_res(scan_res);
1500
1501         wpa_bss_update_start(wpa_s);
1502         for (i = 0; i < scan_res->num; i++)
1503                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
1504         wpa_bss_update_end(wpa_s, info, new_scan);
1505
1506         return scan_res;
1507 }
1508
1509
1510 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1511 {
1512         struct wpa_scan_results *scan_res;
1513         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1514         if (scan_res == NULL)
1515                 return -1;
1516         wpa_scan_results_free(scan_res);
1517
1518         return 0;
1519 }