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 "notify.h"
  21 #include "bss.h"
  22 #include "scan.h"
  23
  24
  25 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
  26 {
  27         struct wpa_ssid *ssid;
  28         union wpa_event_data data;
  29
  30         ssid = wpa_supplicant_get_ssid(wpa_s);
  31         if (ssid == NULL)
  32                 return;
  33
  34         if (wpa_s->current_ssid == NULL) {
  35                 wpa_s->current_ssid = ssid;
  36                 if (wpa_s->current_ssid != NULL)
  37                         wpas_notify_network_changed(wpa_s);
  38         }
  39         wpa_supplicant_initiate_eapol(wpa_s);
  40         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
  41                 "network - generating associated event");
  42         os_memset(&data, 0, sizeof(data));
  43         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
  44 }
  45
  46
  47 #ifdef CONFIG_WPS
  48 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
  49                            enum wps_request_type *req_type)
  50 {
  51         struct wpa_ssid *ssid;
  52         int wps = 0;
  53
  54         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
  55                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
  56                         continue;
  57
  58                 wps = 1;
  59                 *req_type = wpas_wps_get_req_type(ssid);
  60                 if (!ssid->eap.phase1)
  61                         continue;
  62
  63                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
  64                         return 2;
  65         }
  66
  67 #ifdef CONFIG_P2P
  68         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p) {
  69                 wpa_s->wps->dev.p2p = 1;
  70                 if (!wps) {
  71                         wps = 1;
  72                         *req_type = WPS_REQ_ENROLLEE_INFO;
  73                 }
  74         }
  75 #endif /* CONFIG_P2P */
  76
  77         return wps;
  78 }
  79 #endif /* CONFIG_WPS */
  80
  81
  82 int wpa_supplicant_enabled_networks(struct wpa_config *conf)
  83 {
  84         struct wpa_ssid *ssid = conf->ssid;
  85         int count = 0;
  86         while (ssid) {
  87                 if (!ssid->disabled)
  88                         count++;
  89                 ssid = ssid->next;
  90         }
  91         return count;
  92 }
  93
  94
  95 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
  96                                      struct wpa_ssid *ssid)
  97 {
  98         while (ssid) {
  99                 if (!ssid->disabled)
 100                         break;
 101                 ssid = ssid->next;
 102         }
 103
 104         /* ap_scan=2 mode - try to associate with each SSID. */
 105         if (ssid == NULL) {
 106                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
 107                         "end of scan list - go back to beginning");
 108                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 109                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 110                 return;
 111         }
 112         if (ssid->next) {
 113                 /* Continue from the next SSID on the next attempt. */
 114                 wpa_s->prev_scan_ssid = ssid;
 115         } else {
 116                 /* Start from the beginning of the SSID list. */
 117                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 118         }
 119         wpa_supplicant_associate(wpa_s, NULL, ssid);
 120 }
 121
 122
 123 static int int_array_len(const int *a)
 124 {
 125         int i;
 126         for (i = 0; a && a[i]; i++)
 127                 ;
 128         return i;
 129 }
 130
 131
 132 static void int_array_concat(int **res, const int *a)
 133 {
 134         int reslen, alen, i;
 135         int *n;
 136
 137         reslen = int_array_len(*res);
 138         alen = int_array_len(a);
 139
 140         n = os_realloc(*res, (reslen + alen + 1) * sizeof(int));
 141         if (n == NULL) {
 142                 os_free(*res);
 143                 *res = NULL;
 144                 return;
 145         }
 146         for (i = 0; i <= alen; i++)
 147                 n[reslen + i] = a[i];
 148         *res = n;
 149 }
 150
 151
 152 static int freq_cmp(const void *a, const void *b)
 153 {
 154         int _a = *(int *) a;
 155         int _b = *(int *) b;
 156
 157         if (_a == 0)
 158                 return 1;
 159         if (_b == 0)
 160                 return -1;
 161         return _a - _b;
 162 }
 163
 164
 165 static void int_array_sort_unique(int *a)
 166 {
 167         int alen;
 168         int i, j;
 169
 170         if (a == NULL)
 171                 return;
 172
 173         alen = int_array_len(a);
 174         qsort(a, alen, sizeof(int), freq_cmp);
 175
 176         i = 0;
 177         j = 1;
 178         while (a[i] && a[j]) {
 179                 if (a[i] == a[j]) {
 180                         j++;
 181                         continue;
 182                 }
 183                 a[++i] = a[j++];
 184         }
 185         if (a[i])
 186                 i++;
 187         a[i] = 0;
 188 }
 189
 190
 191 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
 192                                 struct wpa_driver_scan_params *params)
 193 {
 194         int ret;
 195
 196         wpa_supplicant_notify_scanning(wpa_s, 1);
 197
 198         ret = wpa_drv_scan(wpa_s, params);
 199         if (ret) {
 200                 wpa_supplicant_notify_scanning(wpa_s, 0);
 201                 wpas_notify_scan_done(wpa_s, 0);
 202         } else {
 203                 wpa_s->scan_runs++;
 204                 wpa_s->normal_scans++;
 205         }
 206
 207         return ret;
 208 }
 209
 210
 211 static void
 212 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 213 {
 214         struct wpa_supplicant *wpa_s = eloop_ctx;
 215
 216         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
 217
 218         if (wpa_supplicant_req_sched_scan(wpa_s))
 219                 wpa_supplicant_req_scan(wpa_s, 0, 0);
 220 }
 221
 222
 223 static void
 224 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
 225 {
 226         struct wpa_supplicant *wpa_s = eloop_ctx;
 227
 228         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
 229
 230         wpa_s->sched_scan_timed_out = 1;
 231         wpa_supplicant_cancel_sched_scan(wpa_s);
 232 }
 233
 234
 235 static int
 236 wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
 237                                 struct wpa_driver_scan_params *params,
 238                                 int interval)
 239 {
 240         int ret;
 241
 242         wpa_supplicant_notify_scanning(wpa_s, 1);
 243         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
 244         if (ret)
 245                 wpa_supplicant_notify_scanning(wpa_s, 0);
 246         else
 247                 wpa_s->sched_scanning = 1;
 248
 249         return ret;
 250 }
 251
 252
 253 static int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
 254 {
 255         int ret;
 256
 257         ret = wpa_drv_stop_sched_scan(wpa_s);
 258         if (ret) {
 259                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
 260                 /* TODO: what to do if stopping fails? */
 261                 return -1;
 262         }
 263
 264         return ret;
 265 }
 266
 267
 268 static struct wpa_driver_scan_filter *
 269 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
 270 {
 271         struct wpa_driver_scan_filter *ssids;
 272         struct wpa_ssid *ssid;
 273         size_t count;
 274
 275         *num_ssids = 0;
 276         if (!conf->filter_ssids)
 277                 return NULL;
 278
 279         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
 280                 if (ssid->ssid && ssid->ssid_len)
 281                         count++;
 282         }
 283         if (count == 0)
 284                 return NULL;
 285         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
 286         if (ssids == NULL)
 287                 return NULL;
 288
 289         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
 290                 if (!ssid->ssid || !ssid->ssid_len)
 291                         continue;
 292                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
 293                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
 294                 (*num_ssids)++;
 295         }
 296
 297         return ssids;
 298 }
 299
 300
 301 static void wpa_supplicant_optimize_freqs(
 302         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
 303 {
 304 #ifdef CONFIG_P2P
 305         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
 306             wpa_s->go_params) {
 307                 /* Optimize provisioning state scan based on GO information */
 308                 if (wpa_s->p2p_in_provisioning < 5 &&
 309                     wpa_s->go_params->freq > 0) {
 310                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
 311                                 "preferred frequency %d MHz",
 312                                 wpa_s->go_params->freq);
 313                         params->freqs = os_zalloc(2 * sizeof(int));
 314                         if (params->freqs)
 315                                 params->freqs[0] = wpa_s->go_params->freq;
 316                 } else if (wpa_s->p2p_in_provisioning < 8 &&
 317                            wpa_s->go_params->freq_list[0]) {
 318                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
 319                                 "channels");
 320                         int_array_concat(&params->freqs,
 321                                          wpa_s->go_params->freq_list);
 322                         if (params->freqs)
 323                                 int_array_sort_unique(params->freqs);
 324                 }
 325                 wpa_s->p2p_in_provisioning++;
 326         }
 327 #endif /* CONFIG_P2P */
 328
 329 #ifdef CONFIG_WPS
 330         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
 331                 /*
 332                  * Optimize post-provisioning scan based on channel used
 333                  * during provisioning.
 334                  */
 335                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
 336                         "that was used during provisioning", wpa_s->wps_freq);
 337                 params->freqs = os_zalloc(2 * sizeof(int));
 338                 if (params->freqs)
 339                         params->freqs[0] = wpa_s->wps_freq;
 340                 wpa_s->after_wps--;
 341         }
 342
 343         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
 344         {
 345                 /* Optimize provisioning scan based on already known channel */
 346                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
 347                         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->known_wps_freq = 0; /* only do this once */
 352         }
 353 #endif /* CONFIG_WPS */
 354 }
 355
 356
 357 #ifdef CONFIG_INTERWORKING
 358 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
 359                                            struct wpabuf *buf)
 360 {
 361         if (wpa_s->conf->interworking == 0)
 362                 return;
 363
 364         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
 365         wpabuf_put_u8(buf, 4);
 366         wpabuf_put_u8(buf, 0x00);
 367         wpabuf_put_u8(buf, 0x00);
 368         wpabuf_put_u8(buf, 0x00);
 369         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
 370
 371         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
 372         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
 373                       1 + ETH_ALEN);
 374         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
 375         /* No Venue Info */
 376         if (!is_zero_ether_addr(wpa_s->conf->hessid))
 377                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
 378 }
 379 #endif /* CONFIG_INTERWORKING */
 380
 381
 382 static struct wpabuf *
 383 wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s,
 384                          struct wpa_driver_scan_params *params)
 385 {
 386         struct wpabuf *extra_ie = NULL;
 387 #ifdef CONFIG_WPS
 388         int wps = 0;
 389         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 390 #endif /* CONFIG_WPS */
 391
 392 #ifdef CONFIG_INTERWORKING
 393         if (wpa_s->conf->interworking &&
 394             wpabuf_resize(&extra_ie, 100) == 0)
 395                 wpas_add_interworking_elements(wpa_s, extra_ie);
 396 #endif /* CONFIG_INTERWORKING */
 397
 398 #ifdef CONFIG_WPS
 399         wps = wpas_wps_in_use(wpa_s, &req_type);
 400
 401         if (wps) {
 402                 struct wpabuf *wps_ie;
 403                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
 404                                                 DEV_PW_DEFAULT,
 405                                                 &wpa_s->wps->dev,
 406                                                 wpa_s->wps->uuid, req_type,
 407                                                 0, NULL);
 408                 if (wps_ie) {
 409                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
 410                                 wpabuf_put_buf(extra_ie, wps_ie);
 411                         wpabuf_free(wps_ie);
 412                 }
 413         }
 414
 415 #ifdef CONFIG_P2P
 416         if (wps) {
 417                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
 418                 if (wpabuf_resize(&extra_ie, ielen) == 0)
 419                         wpas_p2p_scan_ie(wpa_s, extra_ie);
 420         }
 421 #endif /* CONFIG_P2P */
 422
 423 #endif /* CONFIG_WPS */
 424
 425         return extra_ie;
 426 }
 427
 428
 429 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 430 {
 431         struct wpa_supplicant *wpa_s = eloop_ctx;
 432         struct wpa_ssid *ssid;
 433         int scan_req = 0, ret;
 434         struct wpabuf *extra_ie;
 435         struct wpa_driver_scan_params params;
 436         size_t max_ssids;
 437         enum wpa_states prev_state;
 438
 439         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
 440                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
 441                 return;
 442         }
 443
 444         if (wpa_s->disconnected && !wpa_s->scan_req) {
 445                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
 446                 return;
 447         }
 448
 449         if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
 450             !wpa_s->scan_req) {
 451                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
 452                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
 453                 return;
 454         }
 455
 456         if (wpa_s->conf->ap_scan != 0 &&
 457             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
 458                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
 459                         "overriding ap_scan configuration");
 460                 wpa_s->conf->ap_scan = 0;
 461                 wpas_notify_ap_scan_changed(wpa_s);
 462         }
 463
 464         if (wpa_s->conf->ap_scan == 0) {
 465                 wpa_supplicant_gen_assoc_event(wpa_s);
 466                 return;
 467         }
 468
 469 #ifdef CONFIG_P2P
 470         if (wpas_p2p_in_progress(wpa_s)) {
 471                 if (wpa_s->wpa_state == WPA_SCANNING) {
 472                         wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
 473                                 "while P2P operation is in progress");
 474                         wpa_supplicant_req_scan(wpa_s, 5, 0);
 475                 } else {
 476                         wpa_dbg(wpa_s, MSG_DEBUG, "Do not request scan while "
 477                                 "P2P operation is in progress");
 478                 }
 479                 return;
 480         }
 481 #endif /* CONFIG_P2P */
 482
 483         if (wpa_s->conf->ap_scan == 2)
 484                 max_ssids = 1;
 485         else {
 486                 max_ssids = wpa_s->max_scan_ssids;
 487                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
 488                         max_ssids = WPAS_MAX_SCAN_SSIDS;
 489         }
 490
 491         scan_req = wpa_s->scan_req;
 492         wpa_s->scan_req = 0;
 493
 494         os_memset(&params, 0, sizeof(params));
 495
 496         prev_state = wpa_s->wpa_state;
 497         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 498             wpa_s->wpa_state == WPA_INACTIVE)
 499                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 500
 501         if (scan_req != 2 && wpa_s->connect_without_scan) {
 502                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 503                         if (ssid == wpa_s->connect_without_scan)
 504                                 break;
 505                 }
 506                 wpa_s->connect_without_scan = NULL;
 507                 if (ssid) {
 508                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
 509                                    "without scan step");
 510                         wpa_supplicant_associate(wpa_s, NULL, ssid);
 511                         return;
 512                 }
 513         }
 514
 515         /* Find the starting point from which to continue scanning */
 516         ssid = wpa_s->conf->ssid;
 517         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
 518                 while (ssid) {
 519                         if (ssid == wpa_s->prev_scan_ssid) {
 520                                 ssid = ssid->next;
 521                                 break;
 522                         }
 523                         ssid = ssid->next;
 524                 }
 525         }
 526
 527         if (scan_req != 2 && wpa_s->conf->ap_scan == 2) {
 528                 wpa_s->connect_without_scan = NULL;
 529                 wpa_s->prev_scan_wildcard = 0;
 530                 wpa_supplicant_assoc_try(wpa_s, ssid);
 531                 return;
 532         } else if (wpa_s->conf->ap_scan == 2) {
 533                 /*
 534                  * User-initiated scan request in ap_scan == 2; scan with
 535                  * wildcard SSID.
 536                  */
 537                 ssid = NULL;
 538         } else {
 539                 struct wpa_ssid *start = ssid, *tssid;
 540                 int freqs_set = 0;
 541                 if (ssid == NULL && max_ssids > 1)
 542                         ssid = wpa_s->conf->ssid;
 543                 while (ssid) {
 544                         if (!ssid->disabled && ssid->scan_ssid) {
 545                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
 546                                                   ssid->ssid, ssid->ssid_len);
 547                                 params.ssids[params.num_ssids].ssid =
 548                                         ssid->ssid;
 549                                 params.ssids[params.num_ssids].ssid_len =
 550                                         ssid->ssid_len;
 551                                 params.num_ssids++;
 552                                 if (params.num_ssids + 1 >= max_ssids)
 553                                         break;
 554                         }
 555                         ssid = ssid->next;
 556                         if (ssid == start)
 557                                 break;
 558                         if (ssid == NULL && max_ssids > 1 &&
 559                             start != wpa_s->conf->ssid)
 560                                 ssid = wpa_s->conf->ssid;
 561                 }
 562
 563                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
 564                         if (tssid->disabled)
 565                                 continue;
 566                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
 567                                 int_array_concat(&params.freqs,
 568                                                  tssid->scan_freq);
 569                         } else {
 570                                 os_free(params.freqs);
 571                                 params.freqs = NULL;
 572                         }
 573                         freqs_set = 1;
 574                 }
 575                 int_array_sort_unique(params.freqs);
 576         }
 577
 578         if (ssid && max_ssids == 1) {
 579                 /*
 580                  * If the driver is limited to 1 SSID at a time interleave
 581                  * wildcard SSID scans with specific SSID scans to avoid
 582                  * waiting a long time for a wildcard scan.
 583                  */
 584                 if (!wpa_s->prev_scan_wildcard) {
 585                         params.ssids[0].ssid = NULL;
 586                         params.ssids[0].ssid_len = 0;
 587                         wpa_s->prev_scan_wildcard = 1;
 588                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
 589                                 "wildcard SSID (Interleave with specific)");
 590                 } else {
 591                         wpa_s->prev_scan_ssid = ssid;
 592                         wpa_s->prev_scan_wildcard = 0;
 593                         wpa_dbg(wpa_s, MSG_DEBUG,
 594                                 "Starting AP scan for specific SSID: %s",
 595                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 596                 }
 597         } else if (ssid) {
 598                 /* max_ssids > 1 */
 599
 600                 wpa_s->prev_scan_ssid = ssid;
 601                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
 602                         "the scan request");
 603                 params.num_ssids++;
 604         } else {
 605                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
 606                 params.num_ssids++;
 607                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
 608                         "SSID");
 609         }
 610
 611         wpa_supplicant_optimize_freqs(wpa_s, &params);
 612         extra_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 613
 614         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
 615                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
 616                         "generated frequency list");
 617                 params.freqs = wpa_s->next_scan_freqs;
 618         } else
 619                 os_free(wpa_s->next_scan_freqs);
 620         wpa_s->next_scan_freqs = NULL;
 621
 622         params.filter_ssids = wpa_supplicant_build_filter_ssids(
 623                 wpa_s->conf, &params.num_filter_ssids);
 624         if (extra_ie) {
 625                 params.extra_ies = wpabuf_head(extra_ie);
 626                 params.extra_ies_len = wpabuf_len(extra_ie);
 627         }
 628
 629 #ifdef CONFIG_P2P
 630         if (wpa_s->p2p_in_provisioning) {
 631                 /*
 632                  * The interface may not yet be in P2P mode, so we have to
 633                  * explicitly request P2P probe to disable CCK rates.
 634                  */
 635                 params.p2p_probe = 1;
 636         }
 637 #endif /* CONFIG_P2P */
 638
 639         ret = wpa_supplicant_trigger_scan(wpa_s, &params);
 640
 641         wpabuf_free(extra_ie);
 642         os_free(params.freqs);
 643         os_free(params.filter_ssids);
 644
 645         if (ret) {
 646                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
 647                 if (prev_state != wpa_s->wpa_state)
 648                         wpa_supplicant_set_state(wpa_s, prev_state);
 649                 wpa_supplicant_req_scan(wpa_s, 1, 0);
 650         }
 651 }
 652
 653
 654 /**
 655  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
 656  * @wpa_s: Pointer to wpa_supplicant data
 657  * @sec: Number of seconds after which to scan
 658  * @usec: Number of microseconds after which to scan
 659  *
 660  * This function is used to schedule a scan for neighboring access points after
 661  * the specified time.
 662  */
 663 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
 664 {
 665         /* If there's at least one network that should be specifically scanned
 666          * then don't cancel the scan and reschedule.  Some drivers do
 667          * background scanning which generates frequent scan results, and that
 668          * causes the specific SSID scan to get continually pushed back and
 669          * never happen, which causes hidden APs to never get probe-scanned.
 670          */
 671         if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
 672             wpa_s->conf->ap_scan == 1) {
 673                 struct wpa_ssid *ssid = wpa_s->conf->ssid;
 674
 675                 while (ssid) {
 676                         if (!ssid->disabled && ssid->scan_ssid)
 677                                 break;
 678                         ssid = ssid->next;
 679                 }
 680                 if (ssid) {
 681                         wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 682                                 "ensure that specific SSID scans occur");
 683                         return;
 684                 }
 685         }
 686
 687         wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
 688                 sec, usec);
 689         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 690         eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
 691 }
 692
 693
 694 /**
 695  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
 696  * @wpa_s: Pointer to wpa_supplicant data
 697  * @sec: Number of seconds after which to scan
 698  * @usec: Number of microseconds after which to scan
 699  *
 700  * This function is used to schedule periodic scans for neighboring
 701  * access points after the specified time.
 702  */
 703 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
 704                                       int sec, int usec)
 705 {
 706         if (!wpa_s->sched_scan_supported)
 707                 return -1;
 708
 709         eloop_register_timeout(sec, usec,
 710                                wpa_supplicant_delayed_sched_scan_timeout,
 711                                wpa_s, NULL);
 712
 713         return 0;
 714 }
 715
 716
 717 /**
 718  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
 719  * @wpa_s: Pointer to wpa_supplicant data
 720  *
 721  * This function is used to schedule periodic scans for neighboring
 722  * access points repeating the scan continuously.
 723  */
 724 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
 725 {
 726         struct wpa_driver_scan_params params;
 727         enum wpa_states prev_state;
 728         struct wpa_ssid *ssid;
 729         struct wpabuf *wps_ie = NULL;
 730         int ret;
 731         unsigned int max_sched_scan_ssids;
 732         int wildcard = 0;
 733         int need_ssids;
 734
 735         if (!wpa_s->sched_scan_supported)
 736                 return -1;
 737
 738         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
 739                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
 740         else
 741                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
 742         if (max_sched_scan_ssids < 1)
 743                 return -1;
 744
 745         if (wpa_s->sched_scanning) {
 746                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
 747                 return 0;
 748         }
 749
 750         need_ssids = 0;
 751         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
 752                 if (!ssid->disabled && !ssid->scan_ssid) {
 753                         /* Use wildcard SSID to find this network */
 754                         wildcard = 1;
 755                 } else if (!ssid->disabled && ssid->ssid_len)
 756                         need_ssids++;
 757
 758 #ifdef CONFIG_WPS
 759                 if (!ssid->disabled && ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
 760                         /*
 761                          * Normal scan is more reliable and faster for WPS
 762                          * operations and since these are for short periods of
 763                          * time, the benefit of trying to use sched_scan would
 764                          * be limited.
 765                          */
 766                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 767                                 "sched_scan for WPS");
 768                         return -1;
 769                 }
 770 #endif /* CONFIG_WPS */
 771         }
 772         if (wildcard)
 773                 need_ssids++;
 774
 775         if (wpa_s->normal_scans < 3 &&
 776             (need_ssids <= wpa_s->max_scan_ssids ||
 777              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
 778                 /*
 779                  * When normal scan can speed up operations, use that for the
 780                  * first operations before starting the sched_scan to allow
 781                  * user space sleep more. We do this only if the normal scan
 782                  * has functionality that is suitable for this or if the
 783                  * sched_scan does not have better support for multiple SSIDs.
 784                  */
 785                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
 786                         "sched_scan for initial scans (normal_scans=%d)",
 787                         wpa_s->normal_scans);
 788                 return -1;
 789         }
 790
 791         os_memset(&params, 0, sizeof(params));
 792
 793         /* If we can't allocate space for the filters, we just don't filter */
 794         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
 795                                         sizeof(struct wpa_driver_scan_filter));
 796
 797         prev_state = wpa_s->wpa_state;
 798         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 799             wpa_s->wpa_state == WPA_INACTIVE)
 800                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 801
 802         /* Find the starting point from which to continue scanning */
 803         ssid = wpa_s->conf->ssid;
 804         if (wpa_s->prev_sched_ssid) {
 805                 while (ssid) {
 806                         if (ssid == wpa_s->prev_sched_ssid) {
 807                                 ssid = ssid->next;
 808                                 break;
 809                         }
 810                         ssid = ssid->next;
 811                 }
 812         }
 813
 814         if (!ssid || !wpa_s->prev_sched_ssid) {
 815                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
 816
 817                 wpa_s->sched_scan_interval = 10;
 818                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
 819                 wpa_s->first_sched_scan = 1;
 820                 ssid = wpa_s->conf->ssid;
 821                 wpa_s->prev_sched_ssid = ssid;
 822         }
 823
 824         if (wildcard) {
 825                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
 826                 params.num_ssids++;
 827         }
 828
 829         while (ssid) {
 830                 if (ssid->disabled)
 831                         goto next;
 832
 833                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
 834                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
 835                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
 836                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 837                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
 838                                   ssid->ssid, ssid->ssid_len);
 839                         params.filter_ssids[params.num_filter_ssids].ssid_len =
 840                                 ssid->ssid_len;
 841                         params.num_filter_ssids++;
 842                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
 843                 {
 844                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
 845                                 "filter for sched_scan - drop filter");
 846                         os_free(params.filter_ssids);
 847                         params.filter_ssids = NULL;
 848                         params.num_filter_ssids = 0;
 849                 }
 850
 851                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
 852                         if (params.num_ssids == max_sched_scan_ssids)
 853                                 break; /* only room for broadcast SSID */
 854                         wpa_dbg(wpa_s, MSG_DEBUG,
 855                                 "add to active scan ssid: %s",
 856                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
 857                         params.ssids[params.num_ssids].ssid =
 858                                 ssid->ssid;
 859                         params.ssids[params.num_ssids].ssid_len =
 860                                 ssid->ssid_len;
 861                         params.num_ssids++;
 862                         if (params.num_ssids >= max_sched_scan_ssids) {
 863                                 wpa_s->prev_sched_ssid = ssid;
 864                                 break;
 865                         }
 866                 }
 867
 868         next:
 869                 wpa_s->prev_sched_ssid = ssid;
 870                 ssid = ssid->next;
 871         }
 872
 873         if (params.num_filter_ssids == 0) {
 874                 os_free(params.filter_ssids);
 875                 params.filter_ssids = NULL;
 876         }
 877
 878         if (wpa_s->wps)
 879                 wps_ie = wpa_supplicant_extra_ies(wpa_s, &params);
 880
 881         if (ssid || !wpa_s->first_sched_scan) {
 882                 wpa_dbg(wpa_s, MSG_DEBUG,
 883                         "Starting sched scan: interval %d (no timeout)",
 884                         wpa_s->sched_scan_interval);
 885         } else {
 886                 wpa_dbg(wpa_s, MSG_DEBUG,
 887                         "Starting sched scan: interval %d timeout %d",
 888                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
 889         }
 890
 891         ret = wpa_supplicant_start_sched_scan(wpa_s, &params,
 892                                               wpa_s->sched_scan_interval);
 893         wpabuf_free(wps_ie);
 894         os_free(params.filter_ssids);
 895         if (ret) {
 896                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
 897                 if (prev_state != wpa_s->wpa_state)
 898                         wpa_supplicant_set_state(wpa_s, prev_state);
 899                 return ret;
 900         }
 901
 902         /* If we have more SSIDs to scan, add a timeout so we scan them too */
 903         if (ssid || !wpa_s->first_sched_scan) {
 904                 wpa_s->sched_scan_timed_out = 0;
 905                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
 906                                        wpa_supplicant_sched_scan_timeout,
 907                                        wpa_s, NULL);
 908                 wpa_s->first_sched_scan = 0;
 909                 wpa_s->sched_scan_timeout /= 2;
 910                 wpa_s->sched_scan_interval *= 2;
 911         }
 912
 913         return 0;
 914 }
 915
 916
 917 /**
 918  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
 919  * @wpa_s: Pointer to wpa_supplicant data
 920  *
 921  * This function is used to cancel a scan request scheduled with
 922  * wpa_supplicant_req_scan().
 923  */
 924 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 925 {
 926         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 927         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 928 }
 929
 930
 931 /**
 932  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
 933  * @wpa_s: Pointer to wpa_supplicant data
 934  *
 935  * This function is used to stop a periodic scheduled scan.
 936  */
 937 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
 938 {
 939         if (!wpa_s->sched_scanning)
 940                 return;
 941
 942         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
 943         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
 944         wpa_supplicant_stop_sched_scan(wpa_s);
 945 }
 946
 947
 948 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
 949                                     int scanning)
 950 {
 951         if (wpa_s->scanning != scanning) {
 952                 wpa_s->scanning = scanning;
 953                 wpas_notify_scanning(wpa_s);
 954         }
 955 }
 956
 957
 958 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
 959 {
 960         int rate = 0;
 961         const u8 *ie;
 962         int i;
 963
 964         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
 965         for (i = 0; ie && i < ie[1]; i++) {
 966                 if ((ie[i + 2] & 0x7f) > rate)
 967                         rate = ie[i + 2] & 0x7f;
 968         }
 969
 970         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
 971         for (i = 0; ie && i < ie[1]; i++) {
 972                 if ((ie[i + 2] & 0x7f) > rate)
 973                         rate = ie[i + 2] & 0x7f;
 974         }
 975
 976         return rate;
 977 }
 978
 979
 980 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
 981 {
 982         const u8 *end, *pos;
 983
 984         pos = (const u8 *) (res + 1);
 985         end = pos + res->ie_len;
 986
 987         while (pos + 1 < end) {
 988                 if (pos + 2 + pos[1] > end)
 989                         break;
 990                 if (pos[0] == ie)
 991                         return pos;
 992                 pos += 2 + pos[1];
 993         }
 994
 995         return NULL;
 996 }
 997
 998
 999 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1000                                   u32 vendor_type)
1001 {
1002         const u8 *end, *pos;
1003
1004         pos = (const u8 *) (res + 1);
1005         end = pos + res->ie_len;
1006
1007         while (pos + 1 < end) {
1008                 if (pos + 2 + pos[1] > end)
1009                         break;
1010                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1011                     vendor_type == WPA_GET_BE32(&pos[2]))
1012                         return pos;
1013                 pos += 2 + pos[1];
1014         }
1015
1016         return NULL;
1017 }
1018
1019
1020 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1021                                              u32 vendor_type)
1022 {
1023         struct wpabuf *buf;
1024         const u8 *end, *pos;
1025
1026         buf = wpabuf_alloc(res->ie_len);
1027         if (buf == NULL)
1028                 return NULL;
1029
1030         pos = (const u8 *) (res + 1);
1031         end = pos + res->ie_len;
1032
1033         while (pos + 1 < end) {
1034                 if (pos + 2 + pos[1] > end)
1035                         break;
1036                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1037                     vendor_type == WPA_GET_BE32(&pos[2]))
1038                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1039                 pos += 2 + pos[1];
1040         }
1041
1042         if (wpabuf_len(buf) == 0) {
1043                 wpabuf_free(buf);
1044                 buf = NULL;
1045         }
1046
1047         return buf;
1048 }
1049
1050
1051 struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
1052         const struct wpa_scan_res *res, u32 vendor_type)
1053 {
1054         struct wpabuf *buf;
1055         const u8 *end, *pos;
1056
1057         if (res->beacon_ie_len == 0)
1058                 return NULL;
1059         buf = wpabuf_alloc(res->beacon_ie_len);
1060         if (buf == NULL)
1061                 return NULL;
1062
1063         pos = (const u8 *) (res + 1);
1064         pos += res->ie_len;
1065         end = pos + res->beacon_ie_len;
1066
1067         while (pos + 1 < end) {
1068                 if (pos + 2 + pos[1] > end)
1069                         break;
1070                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1071                     vendor_type == WPA_GET_BE32(&pos[2]))
1072                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1073                 pos += 2 + pos[1];
1074         }
1075
1076         if (wpabuf_len(buf) == 0) {
1077                 wpabuf_free(buf);
1078                 buf = NULL;
1079         }
1080
1081         return buf;
1082 }
1083
1084
1085 /*
1086  * Channels with a great SNR can operate at full rate. What is a great SNR?
1087  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1088  * rule of thumb is that any SNR above 20 is good." This one
1089  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1090  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1091  * conservative value.
1092  */
1093 #define GREAT_SNR 30
1094
1095 /* Compare function for sorting scan results. Return >0 if @b is considered
1096  * better. */
1097 static int wpa_scan_result_compar(const void *a, const void *b)
1098 {
1099 #define IS_5GHZ(n) (n > 4000)
1100 #define MIN(a,b) a < b ? a : b
1101         struct wpa_scan_res **_wa = (void *) a;
1102         struct wpa_scan_res **_wb = (void *) b;
1103         struct wpa_scan_res *wa = *_wa;
1104         struct wpa_scan_res *wb = *_wb;
1105         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1106         int snr_a, snr_b;
1107
1108         /* WPA/WPA2 support preferred */
1109         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1110                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1111         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1112                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1113
1114         if (wpa_b && !wpa_a)
1115                 return 1;
1116         if (!wpa_b && wpa_a)
1117                 return -1;
1118
1119         /* privacy support preferred */
1120         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1121             (wb->caps & IEEE80211_CAP_PRIVACY))
1122                 return 1;
1123         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1124             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1125                 return -1;
1126
1127         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1128             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1129                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1130                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1131         } else {
1132                 /* Not suitable information to calculate SNR, so use level */
1133                 snr_a = wa->level;
1134                 snr_b = wb->level;
1135         }
1136
1137         /* best/max rate preferred if SNR close enough */
1138         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1139             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1140                 maxrate_a = wpa_scan_get_max_rate(wa);
1141                 maxrate_b = wpa_scan_get_max_rate(wb);
1142                 if (maxrate_a != maxrate_b)
1143                         return maxrate_b - maxrate_a;
1144                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1145                         return IS_5GHZ(wa->freq) ? -1 : 1;
1146         }
1147
1148         /* use freq for channel preference */
1149
1150         /* all things being equal, use SNR; if SNRs are
1151          * identical, use quality values since some drivers may only report
1152          * that value and leave the signal level zero */
1153         if (snr_b == snr_a)
1154                 return wb->qual - wa->qual;
1155         return snr_b - snr_a;
1156 #undef MIN
1157 #undef IS_5GHZ
1158 }
1159
1160
1161 #ifdef CONFIG_WPS
1162 /* Compare function for sorting scan results when searching a WPS AP for
1163  * provisioning. Return >0 if @b is considered better. */
1164 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1165 {
1166         struct wpa_scan_res **_wa = (void *) a;
1167         struct wpa_scan_res **_wb = (void *) b;
1168         struct wpa_scan_res *wa = *_wa;
1169         struct wpa_scan_res *wb = *_wb;
1170         int uses_wps_a, uses_wps_b;
1171         struct wpabuf *wps_a, *wps_b;
1172         int res;
1173
1174         /* Optimization - check WPS IE existence before allocated memory and
1175          * doing full reassembly. */
1176         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1177         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1178         if (uses_wps_a && !uses_wps_b)
1179                 return -1;
1180         if (!uses_wps_a && uses_wps_b)
1181                 return 1;
1182
1183         if (uses_wps_a && uses_wps_b) {
1184                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1185                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1186                 res = wps_ap_priority_compar(wps_a, wps_b);
1187                 wpabuf_free(wps_a);
1188                 wpabuf_free(wps_b);
1189                 if (res)
1190                         return res;
1191         }
1192
1193         /*
1194          * Do not use current AP security policy as a sorting criteria during
1195          * WPS provisioning step since the AP may get reconfigured at the
1196          * completion of provisioning.
1197          */
1198
1199         /* all things being equal, use signal level; if signal levels are
1200          * identical, use quality values since some drivers may only report
1201          * that value and leave the signal level zero */
1202         if (wb->level == wa->level)
1203                 return wb->qual - wa->qual;
1204         return wb->level - wa->level;
1205 }
1206 #endif /* CONFIG_WPS */
1207
1208
1209 static void dump_scan_res(struct wpa_scan_results *scan_res)
1210 {
1211 #ifndef CONFIG_NO_STDOUT_DEBUG
1212         size_t i;
1213
1214         if (scan_res->res == NULL || scan_res->num == 0)
1215                 return;
1216
1217         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1218
1219         for (i = 0; i < scan_res->num; i++) {
1220                 struct wpa_scan_res *r = scan_res->res[i];
1221                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1222                     == WPA_SCAN_LEVEL_DBM) {
1223                         int snr = r->level - r->noise;
1224                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1225                                    "noise=%d level=%d snr=%d%s flags=0x%x",
1226                                    MAC2STR(r->bssid), r->freq, r->qual,
1227                                    r->noise, r->level, snr,
1228                                    snr >= GREAT_SNR ? "*" : "", r->flags);
1229                 } else {
1230                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1231                                    "noise=%d level=%d flags=0x%x",
1232                                    MAC2STR(r->bssid), r->freq, r->qual,
1233                                    r->noise, r->level, r->flags);
1234                 }
1235         }
1236 #endif /* CONFIG_NO_STDOUT_DEBUG */
1237 }
1238
1239
1240 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1241                                       const u8 *bssid)
1242 {
1243         size_t i;
1244
1245         if (wpa_s->bssid_filter == NULL)
1246                 return 1;
1247
1248         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1249                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1250                               ETH_ALEN) == 0)
1251                         return 1;
1252         }
1253
1254         return 0;
1255 }
1256
1257
1258 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1259                             struct wpa_scan_results *res)
1260 {
1261         size_t i, j;
1262
1263         if (wpa_s->bssid_filter == NULL)
1264                 return;
1265
1266         for (i = 0, j = 0; i < res->num; i++) {
1267                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1268                                                       res->res[i]->bssid)) {
1269                         res->res[j++] = res->res[i];
1270                 } else {
1271                         os_free(res->res[i]);
1272                         res->res[i] = NULL;
1273                 }
1274         }
1275
1276         if (res->num != j) {
1277                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1278                            (int) (res->num - j));
1279                 res->num = j;
1280         }
1281 }
1282
1283
1284 /**
1285  * wpa_supplicant_get_scan_results - Get scan results
1286  * @wpa_s: Pointer to wpa_supplicant data
1287  * @info: Information about what was scanned or %NULL if not available
1288  * @new_scan: Whether a new scan was performed
1289  * Returns: Scan results, %NULL on failure
1290  *
1291  * This function request the current scan results from the driver and updates
1292  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1293  * results with wpa_scan_results_free().
1294  */
1295 struct wpa_scan_results *
1296 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1297                                 struct scan_info *info, int new_scan)
1298 {
1299         struct wpa_scan_results *scan_res;
1300         size_t i;
1301         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1302
1303         scan_res = wpa_drv_get_scan_results2(wpa_s);
1304         if (scan_res == NULL) {
1305                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1306                 return NULL;
1307         }
1308         filter_scan_res(wpa_s, scan_res);
1309
1310 #ifdef CONFIG_WPS
1311         if (wpas_wps_in_progress(wpa_s)) {
1312                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1313                         "provisioning rules");
1314                 compar = wpa_scan_result_wps_compar;
1315         }
1316 #endif /* CONFIG_WPS */
1317
1318         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1319               compar);
1320         dump_scan_res(scan_res);
1321
1322         wpa_bss_update_start(wpa_s);
1323         for (i = 0; i < scan_res->num; i++)
1324                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
1325         wpa_bss_update_end(wpa_s, info, new_scan);
1326
1327         return scan_res;
1328 }
1329
1330
1331 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1332 {
1333         struct wpa_scan_results *scan_res;
1334         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1335         if (scan_res == NULL)
1336                 return -1;
1337         wpa_scan_results_free(scan_res);
1338
1339         return 0;
1340 }