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