30da097d902fc30cc44aecfc8c9a179d0d45e57d
[mech_eap.git] / wpa_supplicant / scan.c
1 /*
2  * WPA Supplicant - Scanning
3  * Copyright (c) 2003-2014, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8
9 #include "utils/includes.h"
10
11 #include "utils/common.h"
12 #include "utils/eloop.h"
13 #include "common/ieee802_11_defs.h"
14 #include "common/wpa_ctrl.h"
15 #include "config.h"
16 #include "wpa_supplicant_i.h"
17 #include "driver_i.h"
18 #include "wps_supplicant.h"
19 #include "p2p_supplicant.h"
20 #include "p2p/p2p.h"
21 #include "hs20_supplicant.h"
22 #include "notify.h"
23 #include "bss.h"
24 #include "scan.h"
25
26
27 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
28 {
29         struct wpa_ssid *ssid;
30         union wpa_event_data data;
31
32         ssid = wpa_supplicant_get_ssid(wpa_s);
33         if (ssid == NULL)
34                 return;
35
36         if (wpa_s->current_ssid == NULL) {
37                 wpa_s->current_ssid = ssid;
38                 if (wpa_s->current_ssid != NULL)
39                         wpas_notify_network_changed(wpa_s);
40         }
41         wpa_supplicant_initiate_eapol(wpa_s);
42         wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
43                 "network - generating associated event");
44         os_memset(&data, 0, sizeof(data));
45         wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
46 }
47
48
49 #ifdef CONFIG_WPS
50 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
51                            enum wps_request_type *req_type)
52 {
53         struct wpa_ssid *ssid;
54         int wps = 0;
55
56         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
57                 if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
58                         continue;
59
60                 wps = 1;
61                 *req_type = wpas_wps_get_req_type(ssid);
62                 if (!ssid->eap.phase1)
63                         continue;
64
65                 if (os_strstr(ssid->eap.phase1, "pbc=1"))
66                         return 2;
67         }
68
69 #ifdef CONFIG_P2P
70         if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
71             !wpa_s->conf->p2p_disabled) {
72                 wpa_s->wps->dev.p2p = 1;
73                 if (!wps) {
74                         wps = 1;
75                         *req_type = WPS_REQ_ENROLLEE_INFO;
76                 }
77         }
78 #endif /* CONFIG_P2P */
79
80         return wps;
81 }
82 #endif /* CONFIG_WPS */
83
84
85 /**
86  * wpa_supplicant_enabled_networks - Check whether there are enabled networks
87  * @wpa_s: Pointer to wpa_supplicant data
88  * Returns: 0 if no networks are enabled, >0 if networks are enabled
89  *
90  * This function is used to figure out whether any networks (or Interworking
91  * with enabled credentials and auto_interworking) are present in the current
92  * configuration.
93  */
94 int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
95 {
96         struct wpa_ssid *ssid = wpa_s->conf->ssid;
97         int count = 0, disabled = 0;
98         while (ssid) {
99                 if (!wpas_network_disabled(wpa_s, ssid))
100                         count++;
101                 else
102                         disabled++;
103                 ssid = ssid->next;
104         }
105         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
106             wpa_s->conf->auto_interworking)
107                 count++;
108         if (count == 0 && disabled > 0) {
109                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
110                         "networks)", disabled);
111         }
112         return count;
113 }
114
115
116 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
117                                      struct wpa_ssid *ssid)
118 {
119         while (ssid) {
120                 if (!wpas_network_disabled(wpa_s, ssid))
121                         break;
122                 ssid = ssid->next;
123         }
124
125         /* ap_scan=2 mode - try to associate with each SSID. */
126         if (ssid == NULL) {
127                 wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
128                         "end of scan list - go back to beginning");
129                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
130                 wpa_supplicant_req_scan(wpa_s, 0, 0);
131                 return;
132         }
133         if (ssid->next) {
134                 /* Continue from the next SSID on the next attempt. */
135                 wpa_s->prev_scan_ssid = ssid;
136         } else {
137                 /* Start from the beginning of the SSID list. */
138                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
139         }
140         wpa_supplicant_associate(wpa_s, NULL, ssid);
141 }
142
143
144 static void wpas_trigger_scan_cb(struct wpa_radio_work *work, int deinit)
145 {
146         struct wpa_supplicant *wpa_s = work->wpa_s;
147         struct wpa_driver_scan_params *params = work->ctx;
148         int ret;
149
150         if (deinit) {
151                 wpa_scan_free_params(params);
152                 return;
153         }
154
155         wpa_supplicant_notify_scanning(wpa_s, 1);
156
157         if (wpa_s->clear_driver_scan_cache)
158                 params->only_new_results = 1;
159         ret = wpa_drv_scan(wpa_s, params);
160         wpa_scan_free_params(params);
161         work->ctx = NULL;
162         if (ret) {
163                 wpa_supplicant_notify_scanning(wpa_s, 0);
164                 wpas_notify_scan_done(wpa_s, 0);
165                 radio_work_done(work);
166                 return;
167         }
168
169         os_get_reltime(&wpa_s->scan_trigger_time);
170         wpa_s->scan_runs++;
171         wpa_s->normal_scans++;
172         wpa_s->own_scan_requested = 1;
173         wpa_s->clear_driver_scan_cache = 0;
174         wpa_s->scan_work = work;
175 }
176
177
178 /**
179  * wpa_supplicant_trigger_scan - Request driver to start a scan
180  * @wpa_s: Pointer to wpa_supplicant data
181  * @params: Scan parameters
182  * Returns: 0 on success, -1 on failure
183  */
184 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
185                                 struct wpa_driver_scan_params *params)
186 {
187         struct wpa_driver_scan_params *ctx;
188
189         if (wpa_s->scan_work) {
190                 wpa_dbg(wpa_s, MSG_INFO, "Reject scan trigger since one is already pending");
191                 return -1;
192         }
193
194         ctx = wpa_scan_clone_params(params);
195         if (ctx == NULL)
196                 return -1;
197
198         if (radio_add_work(wpa_s, 0, "scan", 0, wpas_trigger_scan_cb, ctx) < 0)
199         {
200                 wpa_scan_free_params(ctx);
201                 return -1;
202         }
203
204         return 0;
205 }
206
207
208 static void
209 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
210 {
211         struct wpa_supplicant *wpa_s = eloop_ctx;
212
213         wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
214
215         if (wpa_supplicant_req_sched_scan(wpa_s))
216                 wpa_supplicant_req_scan(wpa_s, 0, 0);
217 }
218
219
220 static void
221 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
222 {
223         struct wpa_supplicant *wpa_s = eloop_ctx;
224
225         wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
226
227         wpa_s->sched_scan_timed_out = 1;
228         wpa_supplicant_cancel_sched_scan(wpa_s);
229 }
230
231
232 int wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
233                                     struct wpa_driver_scan_params *params,
234                                     int interval)
235 {
236         int ret;
237
238         wpa_supplicant_notify_scanning(wpa_s, 1);
239         ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
240         if (ret)
241                 wpa_supplicant_notify_scanning(wpa_s, 0);
242         else
243                 wpa_s->sched_scanning = 1;
244
245         return ret;
246 }
247
248
249 int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
250 {
251         int ret;
252
253         ret = wpa_drv_stop_sched_scan(wpa_s);
254         if (ret) {
255                 wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
256                 /* TODO: what to do if stopping fails? */
257                 return -1;
258         }
259
260         return ret;
261 }
262
263
264 static struct wpa_driver_scan_filter *
265 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
266 {
267         struct wpa_driver_scan_filter *ssids;
268         struct wpa_ssid *ssid;
269         size_t count;
270
271         *num_ssids = 0;
272         if (!conf->filter_ssids)
273                 return NULL;
274
275         for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
276                 if (ssid->ssid && ssid->ssid_len)
277                         count++;
278         }
279         if (count == 0)
280                 return NULL;
281         ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
282         if (ssids == NULL)
283                 return NULL;
284
285         for (ssid = conf->ssid; ssid; ssid = ssid->next) {
286                 if (!ssid->ssid || !ssid->ssid_len)
287                         continue;
288                 os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
289                 ssids[*num_ssids].ssid_len = ssid->ssid_len;
290                 (*num_ssids)++;
291         }
292
293         return ssids;
294 }
295
296
297 static void wpa_supplicant_optimize_freqs(
298         struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
299 {
300 #ifdef CONFIG_P2P
301         if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
302             wpa_s->go_params) {
303                 /* Optimize provisioning state scan based on GO information */
304                 if (wpa_s->p2p_in_provisioning < 5 &&
305                     wpa_s->go_params->freq > 0) {
306                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
307                                 "preferred frequency %d MHz",
308                                 wpa_s->go_params->freq);
309                         params->freqs = os_zalloc(2 * sizeof(int));
310                         if (params->freqs)
311                                 params->freqs[0] = wpa_s->go_params->freq;
312                 } else if (wpa_s->p2p_in_provisioning < 8 &&
313                            wpa_s->go_params->freq_list[0]) {
314                         wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
315                                 "channels");
316                         int_array_concat(&params->freqs,
317                                          wpa_s->go_params->freq_list);
318                         if (params->freqs)
319                                 int_array_sort_unique(params->freqs);
320                 }
321                 wpa_s->p2p_in_provisioning++;
322         }
323 #endif /* CONFIG_P2P */
324
325 #ifdef CONFIG_WPS
326         if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
327                 /*
328                  * Optimize post-provisioning scan based on channel used
329                  * during provisioning.
330                  */
331                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
332                         "that was used during provisioning", wpa_s->wps_freq);
333                 params->freqs = os_zalloc(2 * sizeof(int));
334                 if (params->freqs)
335                         params->freqs[0] = wpa_s->wps_freq;
336                 wpa_s->after_wps--;
337         } else if (wpa_s->after_wps)
338                 wpa_s->after_wps--;
339
340         if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
341         {
342                 /* Optimize provisioning scan based on already known channel */
343                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
344                         wpa_s->wps_freq);
345                 params->freqs = os_zalloc(2 * sizeof(int));
346                 if (params->freqs)
347                         params->freqs[0] = wpa_s->wps_freq;
348                 wpa_s->known_wps_freq = 0; /* only do this once */
349         }
350 #endif /* CONFIG_WPS */
351 }
352
353
354 #ifdef CONFIG_INTERWORKING
355 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
356                                            struct wpabuf *buf)
357 {
358         if (wpa_s->conf->interworking == 0)
359                 return;
360
361         wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
362         wpabuf_put_u8(buf, 4);
363         wpabuf_put_u8(buf, 0x00);
364         wpabuf_put_u8(buf, 0x00);
365         wpabuf_put_u8(buf, 0x00);
366         wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
367
368         wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
369         wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
370                       1 + ETH_ALEN);
371         wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
372         /* No Venue Info */
373         if (!is_zero_ether_addr(wpa_s->conf->hessid))
374                 wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
375 }
376 #endif /* CONFIG_INTERWORKING */
377
378
379 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
380 {
381         struct wpabuf *extra_ie = NULL;
382 #ifdef CONFIG_WPS
383         int wps = 0;
384         enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
385 #endif /* CONFIG_WPS */
386
387 #ifdef CONFIG_INTERWORKING
388         if (wpa_s->conf->interworking &&
389             wpabuf_resize(&extra_ie, 100) == 0)
390                 wpas_add_interworking_elements(wpa_s, extra_ie);
391 #endif /* CONFIG_INTERWORKING */
392
393 #ifdef CONFIG_WPS
394         wps = wpas_wps_in_use(wpa_s, &req_type);
395
396         if (wps) {
397                 struct wpabuf *wps_ie;
398                 wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
399                                                 DEV_PW_DEFAULT,
400                                                 &wpa_s->wps->dev,
401                                                 wpa_s->wps->uuid, req_type,
402                                                 0, NULL);
403                 if (wps_ie) {
404                         if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
405                                 wpabuf_put_buf(extra_ie, wps_ie);
406                         wpabuf_free(wps_ie);
407                 }
408         }
409
410 #ifdef CONFIG_P2P
411         if (wps) {
412                 size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
413                 if (wpabuf_resize(&extra_ie, ielen) == 0)
414                         wpas_p2p_scan_ie(wpa_s, extra_ie);
415         }
416 #endif /* CONFIG_P2P */
417
418 #endif /* CONFIG_WPS */
419
420 #ifdef CONFIG_HS20
421         if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
422                 wpas_hs20_add_indication(extra_ie);
423 #endif /* CONFIG_HS20 */
424
425         return extra_ie;
426 }
427
428
429 #ifdef CONFIG_P2P
430
431 /*
432  * Check whether there are any enabled networks or credentials that could be
433  * used for a non-P2P connection.
434  */
435 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
436 {
437         struct wpa_ssid *ssid;
438
439         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
440                 if (wpas_network_disabled(wpa_s, ssid))
441                         continue;
442                 if (!ssid->p2p_group)
443                         return 1;
444         }
445
446         if (wpa_s->conf->cred && wpa_s->conf->interworking &&
447             wpa_s->conf->auto_interworking)
448                 return 1;
449
450         return 0;
451 }
452
453 #endif /* CONFIG_P2P */
454
455
456 static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
457                                           u16 num_modes,
458                                           enum hostapd_hw_mode mode)
459 {
460         u16 i;
461
462         for (i = 0; i < num_modes; i++) {
463                 if (modes[i].mode == mode)
464                         return &modes[i];
465         }
466
467         return NULL;
468 }
469
470
471 static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
472                                         enum hostapd_hw_mode band,
473                                         struct wpa_driver_scan_params *params)
474 {
475         /* Include only supported channels for the specified band */
476         struct hostapd_hw_modes *mode;
477         int count, i;
478
479         mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
480         if (mode == NULL) {
481                 /* No channels supported in this band - use empty list */
482                 params->freqs = os_zalloc(sizeof(int));
483                 return;
484         }
485
486         params->freqs = os_zalloc((mode->num_channels + 1) * sizeof(int));
487         if (params->freqs == NULL)
488                 return;
489         for (count = 0, i = 0; i < mode->num_channels; i++) {
490                 if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
491                         continue;
492                 params->freqs[count++] = mode->channels[i].freq;
493         }
494 }
495
496
497 static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
498                                    struct wpa_driver_scan_params *params)
499 {
500         if (wpa_s->hw.modes == NULL)
501                 return; /* unknown what channels the driver supports */
502         if (params->freqs)
503                 return; /* already using a limited channel set */
504         if (wpa_s->setband == WPA_SETBAND_5G)
505                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
506                                             params);
507         else if (wpa_s->setband == WPA_SETBAND_2G)
508                 wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
509                                             params);
510 }
511
512
513 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
514 {
515         struct wpa_supplicant *wpa_s = eloop_ctx;
516         struct wpa_ssid *ssid;
517         int ret;
518         struct wpabuf *extra_ie = NULL;
519         struct wpa_driver_scan_params params;
520         struct wpa_driver_scan_params *scan_params;
521         size_t max_ssids;
522         enum wpa_states prev_state;
523
524         if (wpa_s->pno || wpa_s->pno_sched_pending) {
525                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - PNO is in progress");
526                 return;
527         }
528
529         if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
530                 wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
531                 return;
532         }
533
534         if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
535                 wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
536                 wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
537                 return;
538         }
539
540         if (wpa_s->scanning) {
541                 /*
542                  * If we are already in scanning state, we shall reschedule the
543                  * the incoming scan request.
544                  */
545                 wpa_dbg(wpa_s, MSG_DEBUG, "Already scanning - Reschedule the incoming scan req");
546                 wpa_supplicant_req_scan(wpa_s, 1, 0);
547                 return;
548         }
549
550         if (!wpa_supplicant_enabled_networks(wpa_s) &&
551             wpa_s->scan_req == NORMAL_SCAN_REQ) {
552                 wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
553                 wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
554                 return;
555         }
556
557         if (wpa_s->conf->ap_scan != 0 &&
558             (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
559                 wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
560                         "overriding ap_scan configuration");
561                 wpa_s->conf->ap_scan = 0;
562                 wpas_notify_ap_scan_changed(wpa_s);
563         }
564
565         if (wpa_s->conf->ap_scan == 0) {
566                 wpa_supplicant_gen_assoc_event(wpa_s);
567                 return;
568         }
569
570 #ifdef CONFIG_P2P
571         if (wpas_p2p_in_progress(wpa_s)) {
572                 wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan while P2P operation is in progress");
573                 wpa_supplicant_req_scan(wpa_s, 5, 0);
574                 return;
575         }
576 #endif /* CONFIG_P2P */
577
578         if (wpa_s->conf->ap_scan == 2)
579                 max_ssids = 1;
580         else {
581                 max_ssids = wpa_s->max_scan_ssids;
582                 if (max_ssids > WPAS_MAX_SCAN_SSIDS)
583                         max_ssids = WPAS_MAX_SCAN_SSIDS;
584         }
585
586         wpa_s->last_scan_req = wpa_s->scan_req;
587         wpa_s->scan_req = NORMAL_SCAN_REQ;
588
589         os_memset(&params, 0, sizeof(params));
590
591         prev_state = wpa_s->wpa_state;
592         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
593             wpa_s->wpa_state == WPA_INACTIVE)
594                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
595
596         /*
597          * If autoscan has set its own scanning parameters
598          */
599         if (wpa_s->autoscan_params != NULL) {
600                 scan_params = wpa_s->autoscan_params;
601                 goto scan;
602         }
603
604         if (wpa_s->last_scan_req != MANUAL_SCAN_REQ &&
605             wpa_s->connect_without_scan) {
606                 for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
607                         if (ssid == wpa_s->connect_without_scan)
608                                 break;
609                 }
610                 wpa_s->connect_without_scan = NULL;
611                 if (ssid) {
612                         wpa_printf(MSG_DEBUG, "Start a pre-selected network "
613                                    "without scan step");
614                         wpa_supplicant_associate(wpa_s, NULL, ssid);
615                         return;
616                 }
617         }
618
619 #ifdef CONFIG_P2P
620         if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
621             wpa_s->go_params) {
622                 wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during P2P group formation (p2p_in_provisioning=%d show_group_started=%d)",
623                            wpa_s->p2p_in_provisioning,
624                            wpa_s->show_group_started);
625                 params.ssids[0].ssid = wpa_s->go_params->ssid;
626                 params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
627                 params.num_ssids = 1;
628                 goto ssid_list_set;
629         }
630 #endif /* CONFIG_P2P */
631
632         /* Find the starting point from which to continue scanning */
633         ssid = wpa_s->conf->ssid;
634         if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
635                 while (ssid) {
636                         if (ssid == wpa_s->prev_scan_ssid) {
637                                 ssid = ssid->next;
638                                 break;
639                         }
640                         ssid = ssid->next;
641                 }
642         }
643
644         if (wpa_s->last_scan_req != MANUAL_SCAN_REQ &&
645             wpa_s->conf->ap_scan == 2) {
646                 wpa_s->connect_without_scan = NULL;
647                 wpa_s->prev_scan_wildcard = 0;
648                 wpa_supplicant_assoc_try(wpa_s, ssid);
649                 return;
650         } else if (wpa_s->conf->ap_scan == 2) {
651                 /*
652                  * User-initiated scan request in ap_scan == 2; scan with
653                  * wildcard SSID.
654                  */
655                 ssid = NULL;
656         } else {
657                 struct wpa_ssid *start = ssid, *tssid;
658                 int freqs_set = 0;
659                 if (ssid == NULL && max_ssids > 1)
660                         ssid = wpa_s->conf->ssid;
661                 while (ssid) {
662                         if (!wpas_network_disabled(wpa_s, ssid) &&
663                             ssid->scan_ssid) {
664                                 wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
665                                                   ssid->ssid, ssid->ssid_len);
666                                 params.ssids[params.num_ssids].ssid =
667                                         ssid->ssid;
668                                 params.ssids[params.num_ssids].ssid_len =
669                                         ssid->ssid_len;
670                                 params.num_ssids++;
671                                 if (params.num_ssids + 1 >= max_ssids)
672                                         break;
673                         }
674                         ssid = ssid->next;
675                         if (ssid == start)
676                                 break;
677                         if (ssid == NULL && max_ssids > 1 &&
678                             start != wpa_s->conf->ssid)
679                                 ssid = wpa_s->conf->ssid;
680                 }
681
682                 for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
683                         if (wpas_network_disabled(wpa_s, tssid))
684                                 continue;
685                         if ((params.freqs || !freqs_set) && tssid->scan_freq) {
686                                 int_array_concat(&params.freqs,
687                                                  tssid->scan_freq);
688                         } else {
689                                 os_free(params.freqs);
690                                 params.freqs = NULL;
691                         }
692                         freqs_set = 1;
693                 }
694                 int_array_sort_unique(params.freqs);
695         }
696
697         if (ssid && max_ssids == 1) {
698                 /*
699                  * If the driver is limited to 1 SSID at a time interleave
700                  * wildcard SSID scans with specific SSID scans to avoid
701                  * waiting a long time for a wildcard scan.
702                  */
703                 if (!wpa_s->prev_scan_wildcard) {
704                         params.ssids[0].ssid = NULL;
705                         params.ssids[0].ssid_len = 0;
706                         wpa_s->prev_scan_wildcard = 1;
707                         wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
708                                 "wildcard SSID (Interleave with specific)");
709                 } else {
710                         wpa_s->prev_scan_ssid = ssid;
711                         wpa_s->prev_scan_wildcard = 0;
712                         wpa_dbg(wpa_s, MSG_DEBUG,
713                                 "Starting AP scan for specific SSID: %s",
714                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
715                 }
716         } else if (ssid) {
717                 /* max_ssids > 1 */
718
719                 wpa_s->prev_scan_ssid = ssid;
720                 wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
721                         "the scan request");
722                 params.num_ssids++;
723         } else if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
724                    wpa_s->manual_scan_passive && params.num_ssids == 0) {
725                 wpa_dbg(wpa_s, MSG_DEBUG, "Use passive scan based on manual request");
726         } else {
727                 wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
728                 params.num_ssids++;
729                 wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
730                         "SSID");
731         }
732 #ifdef CONFIG_P2P
733 ssid_list_set:
734 #endif /* CONFIG_P2P */
735
736         wpa_supplicant_optimize_freqs(wpa_s, &params);
737         extra_ie = wpa_supplicant_extra_ies(wpa_s);
738
739         if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
740             wpa_s->manual_scan_only_new)
741                 params.only_new_results = 1;
742
743         if (wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs == NULL &&
744             wpa_s->manual_scan_freqs) {
745                 wpa_dbg(wpa_s, MSG_DEBUG, "Limit manual scan to specified channels");
746                 params.freqs = wpa_s->manual_scan_freqs;
747                 wpa_s->manual_scan_freqs = NULL;
748         }
749
750         if (params.freqs == NULL && wpa_s->next_scan_freqs) {
751                 wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
752                         "generated frequency list");
753                 params.freqs = wpa_s->next_scan_freqs;
754         } else
755                 os_free(wpa_s->next_scan_freqs);
756         wpa_s->next_scan_freqs = NULL;
757         wpa_setband_scan_freqs(wpa_s, &params);
758
759         /* See if user specified frequencies. If so, scan only those. */
760         if (wpa_s->conf->freq_list && !params.freqs) {
761                 wpa_dbg(wpa_s, MSG_DEBUG,
762                         "Optimize scan based on conf->freq_list");
763                 int_array_concat(&params.freqs, wpa_s->conf->freq_list);
764         }
765
766         /* Use current associated channel? */
767         if (wpa_s->conf->scan_cur_freq && !params.freqs) {
768                 unsigned int num = wpa_s->num_multichan_concurrent;
769
770                 params.freqs = os_calloc(num + 1, sizeof(int));
771                 if (params.freqs) {
772                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
773                         if (num > 0) {
774                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the "
775                                         "current operating channels since "
776                                         "scan_cur_freq is enabled");
777                         } else {
778                                 os_free(params.freqs);
779                                 params.freqs = NULL;
780                         }
781                 }
782         }
783
784         params.filter_ssids = wpa_supplicant_build_filter_ssids(
785                 wpa_s->conf, &params.num_filter_ssids);
786         if (extra_ie) {
787                 params.extra_ies = wpabuf_head(extra_ie);
788                 params.extra_ies_len = wpabuf_len(extra_ie);
789         }
790
791 #ifdef CONFIG_P2P
792         if (wpa_s->p2p_in_provisioning ||
793             (wpa_s->show_group_started && wpa_s->go_params)) {
794                 /*
795                  * The interface may not yet be in P2P mode, so we have to
796                  * explicitly request P2P probe to disable CCK rates.
797                  */
798                 params.p2p_probe = 1;
799         }
800 #endif /* CONFIG_P2P */
801
802         scan_params = &params;
803
804 scan:
805 #ifdef CONFIG_P2P
806         /*
807          * If the driver does not support multi-channel concurrency and a
808          * virtual interface that shares the same radio with the wpa_s interface
809          * is operating there may not be need to scan other channels apart from
810          * the current operating channel on the other virtual interface. Filter
811          * out other channels in case we are trying to find a connection for a
812          * station interface when we are not configured to prefer station
813          * connection and a concurrent operation is already in process.
814          */
815         if (wpa_s->scan_for_connection &&
816             wpa_s->last_scan_req == NORMAL_SCAN_REQ &&
817             !scan_params->freqs && !params.freqs &&
818             wpas_is_p2p_prioritized(wpa_s) &&
819             wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
820             non_p2p_network_enabled(wpa_s)) {
821                 unsigned int num = wpa_s->num_multichan_concurrent;
822
823                 params.freqs = os_calloc(num + 1, sizeof(int));
824                 if (params.freqs) {
825                         num = get_shared_radio_freqs(wpa_s, params.freqs, num);
826                         if (num > 0 && num == wpa_s->num_multichan_concurrent) {
827                                 wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current operating channels since all channels are already used");
828                         } else {
829                                 os_free(params.freqs);
830                                 params.freqs = NULL;
831                         }
832                 }
833         }
834 #endif /* CONFIG_P2P */
835
836         ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
837
838         if (ret && wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs &&
839             !wpa_s->manual_scan_freqs) {
840                 /* Restore manual_scan_freqs for the next attempt */
841                 wpa_s->manual_scan_freqs = params.freqs;
842                 params.freqs = NULL;
843         }
844
845         wpabuf_free(extra_ie);
846         os_free(params.freqs);
847         os_free(params.filter_ssids);
848
849         if (ret) {
850                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
851                 if (prev_state != wpa_s->wpa_state)
852                         wpa_supplicant_set_state(wpa_s, prev_state);
853                 /* Restore scan_req since we will try to scan again */
854                 wpa_s->scan_req = wpa_s->last_scan_req;
855                 wpa_supplicant_req_scan(wpa_s, 1, 0);
856         } else {
857                 wpa_s->scan_for_connection = 0;
858         }
859 }
860
861
862 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
863 {
864         struct os_reltime remaining, new_int;
865         int cancelled;
866
867         cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
868                                              &remaining);
869
870         new_int.sec = sec;
871         new_int.usec = 0;
872         if (cancelled && os_reltime_before(&remaining, &new_int)) {
873                 new_int.sec = remaining.sec;
874                 new_int.usec = remaining.usec;
875         }
876
877         if (cancelled) {
878                 eloop_register_timeout(new_int.sec, new_int.usec,
879                                        wpa_supplicant_scan, wpa_s, NULL);
880         }
881         wpa_s->scan_interval = sec;
882 }
883
884
885 /**
886  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
887  * @wpa_s: Pointer to wpa_supplicant data
888  * @sec: Number of seconds after which to scan
889  * @usec: Number of microseconds after which to scan
890  *
891  * This function is used to schedule a scan for neighboring access points after
892  * the specified time.
893  */
894 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
895 {
896         int res = eloop_deplete_timeout(sec, usec, wpa_supplicant_scan, wpa_s,
897                                         NULL);
898         if (res == 1) {
899                 wpa_dbg(wpa_s, MSG_DEBUG, "Rescheduling scan request: %d.%06d sec",
900                         sec, usec);
901         } else if (res == 0) {
902                 wpa_dbg(wpa_s, MSG_DEBUG, "Ignore new scan request for %d.%06d sec since an earlier request is scheduled to trigger sooner",
903                         sec, usec);
904         } else {
905                 wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d.%06d sec",
906                         sec, usec);
907                 eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
908         }
909 }
910
911
912 /**
913  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
914  * @wpa_s: Pointer to wpa_supplicant data
915  * @sec: Number of seconds after which to scan
916  * @usec: Number of microseconds after which to scan
917  * Returns: 0 on success or -1 otherwise
918  *
919  * This function is used to schedule periodic scans for neighboring
920  * access points after the specified time.
921  */
922 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
923                                       int sec, int usec)
924 {
925         if (!wpa_s->sched_scan_supported)
926                 return -1;
927
928         eloop_register_timeout(sec, usec,
929                                wpa_supplicant_delayed_sched_scan_timeout,
930                                wpa_s, NULL);
931
932         return 0;
933 }
934
935
936 /**
937  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
938  * @wpa_s: Pointer to wpa_supplicant data
939  * Returns: 0 is sched_scan was started or -1 otherwise
940  *
941  * This function is used to schedule periodic scans for neighboring
942  * access points repeating the scan continuously.
943  */
944 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
945 {
946         struct wpa_driver_scan_params params;
947         struct wpa_driver_scan_params *scan_params;
948         enum wpa_states prev_state;
949         struct wpa_ssid *ssid = NULL;
950         struct wpabuf *extra_ie = NULL;
951         int ret;
952         unsigned int max_sched_scan_ssids;
953         int wildcard = 0;
954         int need_ssids;
955
956         if (!wpa_s->sched_scan_supported)
957                 return -1;
958
959         if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
960                 max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
961         else
962                 max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
963         if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
964                 return -1;
965
966         if (wpa_s->sched_scanning) {
967                 wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
968                 return 0;
969         }
970
971         need_ssids = 0;
972         for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
973                 if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
974                         /* Use wildcard SSID to find this network */
975                         wildcard = 1;
976                 } else if (!wpas_network_disabled(wpa_s, ssid) &&
977                            ssid->ssid_len)
978                         need_ssids++;
979
980 #ifdef CONFIG_WPS
981                 if (!wpas_network_disabled(wpa_s, ssid) &&
982                     ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
983                         /*
984                          * Normal scan is more reliable and faster for WPS
985                          * operations and since these are for short periods of
986                          * time, the benefit of trying to use sched_scan would
987                          * be limited.
988                          */
989                         wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
990                                 "sched_scan for WPS");
991                         return -1;
992                 }
993 #endif /* CONFIG_WPS */
994         }
995         if (wildcard)
996                 need_ssids++;
997
998         if (wpa_s->normal_scans < 3 &&
999             (need_ssids <= wpa_s->max_scan_ssids ||
1000              wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
1001                 /*
1002                  * When normal scan can speed up operations, use that for the
1003                  * first operations before starting the sched_scan to allow
1004                  * user space sleep more. We do this only if the normal scan
1005                  * has functionality that is suitable for this or if the
1006                  * sched_scan does not have better support for multiple SSIDs.
1007                  */
1008                 wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1009                         "sched_scan for initial scans (normal_scans=%d)",
1010                         wpa_s->normal_scans);
1011                 return -1;
1012         }
1013
1014         os_memset(&params, 0, sizeof(params));
1015
1016         /* If we can't allocate space for the filters, we just don't filter */
1017         params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
1018                                         sizeof(struct wpa_driver_scan_filter));
1019
1020         prev_state = wpa_s->wpa_state;
1021         if (wpa_s->wpa_state == WPA_DISCONNECTED ||
1022             wpa_s->wpa_state == WPA_INACTIVE)
1023                 wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
1024
1025         if (wpa_s->autoscan_params != NULL) {
1026                 scan_params = wpa_s->autoscan_params;
1027                 goto scan;
1028         }
1029
1030         /* Find the starting point from which to continue scanning */
1031         ssid = wpa_s->conf->ssid;
1032         if (wpa_s->prev_sched_ssid) {
1033                 while (ssid) {
1034                         if (ssid == wpa_s->prev_sched_ssid) {
1035                                 ssid = ssid->next;
1036                                 break;
1037                         }
1038                         ssid = ssid->next;
1039                 }
1040         }
1041
1042         if (!ssid || !wpa_s->prev_sched_ssid) {
1043                 wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
1044                 if (wpa_s->conf->sched_scan_interval)
1045                         wpa_s->sched_scan_interval =
1046                                 wpa_s->conf->sched_scan_interval;
1047                 if (wpa_s->sched_scan_interval == 0)
1048                         wpa_s->sched_scan_interval = 10;
1049                 wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1050                 wpa_s->first_sched_scan = 1;
1051                 ssid = wpa_s->conf->ssid;
1052                 wpa_s->prev_sched_ssid = ssid;
1053         }
1054
1055         if (wildcard) {
1056                 wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1057                 params.num_ssids++;
1058         }
1059
1060         while (ssid) {
1061                 if (wpas_network_disabled(wpa_s, ssid))
1062                         goto next;
1063
1064                 if (params.num_filter_ssids < wpa_s->max_match_sets &&
1065                     params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1066                         wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1067                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1068                         os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1069                                   ssid->ssid, ssid->ssid_len);
1070                         params.filter_ssids[params.num_filter_ssids].ssid_len =
1071                                 ssid->ssid_len;
1072                         params.num_filter_ssids++;
1073                 } else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1074                 {
1075                         wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1076                                 "filter for sched_scan - drop filter");
1077                         os_free(params.filter_ssids);
1078                         params.filter_ssids = NULL;
1079                         params.num_filter_ssids = 0;
1080                 }
1081
1082                 if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1083                         if (params.num_ssids == max_sched_scan_ssids)
1084                                 break; /* only room for broadcast SSID */
1085                         wpa_dbg(wpa_s, MSG_DEBUG,
1086                                 "add to active scan ssid: %s",
1087                                 wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1088                         params.ssids[params.num_ssids].ssid =
1089                                 ssid->ssid;
1090                         params.ssids[params.num_ssids].ssid_len =
1091                                 ssid->ssid_len;
1092                         params.num_ssids++;
1093                         if (params.num_ssids >= max_sched_scan_ssids) {
1094                                 wpa_s->prev_sched_ssid = ssid;
1095                                 do {
1096                                         ssid = ssid->next;
1097                                 } while (ssid &&
1098                                          (wpas_network_disabled(wpa_s, ssid) ||
1099                                           !ssid->scan_ssid));
1100                                 break;
1101                         }
1102                 }
1103
1104         next:
1105                 wpa_s->prev_sched_ssid = ssid;
1106                 ssid = ssid->next;
1107         }
1108
1109         if (params.num_filter_ssids == 0) {
1110                 os_free(params.filter_ssids);
1111                 params.filter_ssids = NULL;
1112         }
1113
1114         extra_ie = wpa_supplicant_extra_ies(wpa_s);
1115         if (extra_ie) {
1116                 params.extra_ies = wpabuf_head(extra_ie);
1117                 params.extra_ies_len = wpabuf_len(extra_ie);
1118         }
1119
1120         if (wpa_s->conf->filter_rssi)
1121                 params.filter_rssi = wpa_s->conf->filter_rssi;
1122
1123         scan_params = &params;
1124
1125 scan:
1126         if (ssid || !wpa_s->first_sched_scan) {
1127                 wpa_dbg(wpa_s, MSG_DEBUG,
1128                         "Starting sched scan: interval %d timeout %d",
1129                         wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1130         } else {
1131                 wpa_dbg(wpa_s, MSG_DEBUG,
1132                         "Starting sched scan: interval %d (no timeout)",
1133                         wpa_s->sched_scan_interval);
1134         }
1135
1136         wpa_setband_scan_freqs(wpa_s, scan_params);
1137
1138         ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1139                                               wpa_s->sched_scan_interval);
1140         wpabuf_free(extra_ie);
1141         os_free(params.filter_ssids);
1142         if (ret) {
1143                 wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1144                 if (prev_state != wpa_s->wpa_state)
1145                         wpa_supplicant_set_state(wpa_s, prev_state);
1146                 return ret;
1147         }
1148
1149         /* If we have more SSIDs to scan, add a timeout so we scan them too */
1150         if (ssid || !wpa_s->first_sched_scan) {
1151                 wpa_s->sched_scan_timed_out = 0;
1152                 eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1153                                        wpa_supplicant_sched_scan_timeout,
1154                                        wpa_s, NULL);
1155                 wpa_s->first_sched_scan = 0;
1156                 wpa_s->sched_scan_timeout /= 2;
1157                 wpa_s->sched_scan_interval *= 2;
1158                 if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
1159                         wpa_s->sched_scan_interval = 10;
1160                         wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1161                 }
1162         }
1163
1164         /* If there is no more ssids, start next time from the beginning */
1165         if (!ssid)
1166                 wpa_s->prev_sched_ssid = NULL;
1167
1168         return 0;
1169 }
1170
1171
1172 /**
1173  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1174  * @wpa_s: Pointer to wpa_supplicant data
1175  *
1176  * This function is used to cancel a scan request scheduled with
1177  * wpa_supplicant_req_scan().
1178  */
1179 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1180 {
1181         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1182         eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1183 }
1184
1185
1186 /**
1187  * wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
1188  * @wpa_s: Pointer to wpa_supplicant data
1189  *
1190  * This function is used to stop a delayed scheduled scan.
1191  */
1192 void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
1193 {
1194         if (!wpa_s->sched_scan_supported)
1195                 return;
1196
1197         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
1198         eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
1199                              wpa_s, NULL);
1200 }
1201
1202
1203 /**
1204  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1205  * @wpa_s: Pointer to wpa_supplicant data
1206  *
1207  * This function is used to stop a periodic scheduled scan.
1208  */
1209 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1210 {
1211         if (!wpa_s->sched_scanning)
1212                 return;
1213
1214         wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1215         eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1216         wpa_supplicant_stop_sched_scan(wpa_s);
1217 }
1218
1219
1220 /**
1221  * wpa_supplicant_notify_scanning - Indicate possible scan state change
1222  * @wpa_s: Pointer to wpa_supplicant data
1223  * @scanning: Whether scanning is currently in progress
1224  *
1225  * This function is to generate scanning notifycations. It is called whenever
1226  * there may have been a change in scanning (scan started, completed, stopped).
1227  * wpas_notify_scanning() is called whenever the scanning state changed from the
1228  * previously notified state.
1229  */
1230 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1231                                     int scanning)
1232 {
1233         if (wpa_s->scanning != scanning) {
1234                 wpa_s->scanning = scanning;
1235                 wpas_notify_scanning(wpa_s);
1236         }
1237 }
1238
1239
1240 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1241 {
1242         int rate = 0;
1243         const u8 *ie;
1244         int i;
1245
1246         ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1247         for (i = 0; ie && i < ie[1]; i++) {
1248                 if ((ie[i + 2] & 0x7f) > rate)
1249                         rate = ie[i + 2] & 0x7f;
1250         }
1251
1252         ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1253         for (i = 0; ie && i < ie[1]; i++) {
1254                 if ((ie[i + 2] & 0x7f) > rate)
1255                         rate = ie[i + 2] & 0x7f;
1256         }
1257
1258         return rate;
1259 }
1260
1261
1262 /**
1263  * wpa_scan_get_ie - Fetch a specified information element from a scan result
1264  * @res: Scan result entry
1265  * @ie: Information element identitifier (WLAN_EID_*)
1266  * Returns: Pointer to the information element (id field) or %NULL if not found
1267  *
1268  * This function returns the first matching information element in the scan
1269  * result.
1270  */
1271 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1272 {
1273         const u8 *end, *pos;
1274
1275         pos = (const u8 *) (res + 1);
1276         end = pos + res->ie_len;
1277
1278         while (pos + 1 < end) {
1279                 if (pos + 2 + pos[1] > end)
1280                         break;
1281                 if (pos[0] == ie)
1282                         return pos;
1283                 pos += 2 + pos[1];
1284         }
1285
1286         return NULL;
1287 }
1288
1289
1290 /**
1291  * wpa_scan_get_vendor_ie - Fetch vendor information element from a scan result
1292  * @res: Scan result entry
1293  * @vendor_type: Vendor type (four octets starting the IE payload)
1294  * Returns: Pointer to the information element (id field) or %NULL if not found
1295  *
1296  * This function returns the first matching information element in the scan
1297  * result.
1298  */
1299 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1300                                   u32 vendor_type)
1301 {
1302         const u8 *end, *pos;
1303
1304         pos = (const u8 *) (res + 1);
1305         end = pos + res->ie_len;
1306
1307         while (pos + 1 < end) {
1308                 if (pos + 2 + pos[1] > end)
1309                         break;
1310                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1311                     vendor_type == WPA_GET_BE32(&pos[2]))
1312                         return pos;
1313                 pos += 2 + pos[1];
1314         }
1315
1316         return NULL;
1317 }
1318
1319
1320 /**
1321  * wpa_scan_get_vendor_ie_beacon - Fetch vendor information from a scan result
1322  * @res: Scan result entry
1323  * @vendor_type: Vendor type (four octets starting the IE payload)
1324  * Returns: Pointer to the information element (id field) or %NULL if not found
1325  *
1326  * This function returns the first matching information element in the scan
1327  * result.
1328  *
1329  * This function is like wpa_scan_get_vendor_ie(), but uses IE buffer only
1330  * from Beacon frames instead of either Beacon or Probe Response frames.
1331  */
1332 const u8 * wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res *res,
1333                                          u32 vendor_type)
1334 {
1335         const u8 *end, *pos;
1336
1337         if (res->beacon_ie_len == 0)
1338                 return NULL;
1339
1340         pos = (const u8 *) (res + 1);
1341         pos += res->ie_len;
1342         end = pos + res->beacon_ie_len;
1343
1344         while (pos + 1 < end) {
1345                 if (pos + 2 + pos[1] > end)
1346                         break;
1347                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1348                     vendor_type == WPA_GET_BE32(&pos[2]))
1349                         return pos;
1350                 pos += 2 + pos[1];
1351         }
1352
1353         return NULL;
1354 }
1355
1356
1357 /**
1358  * wpa_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
1359  * @res: Scan result entry
1360  * @vendor_type: Vendor type (four octets starting the IE payload)
1361  * Returns: Pointer to the information element payload or %NULL if not found
1362  *
1363  * This function returns concatenated payload of possibly fragmented vendor
1364  * specific information elements in the scan result. The caller is responsible
1365  * for freeing the returned buffer.
1366  */
1367 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1368                                              u32 vendor_type)
1369 {
1370         struct wpabuf *buf;
1371         const u8 *end, *pos;
1372
1373         buf = wpabuf_alloc(res->ie_len);
1374         if (buf == NULL)
1375                 return NULL;
1376
1377         pos = (const u8 *) (res + 1);
1378         end = pos + res->ie_len;
1379
1380         while (pos + 1 < end) {
1381                 if (pos + 2 + pos[1] > end)
1382                         break;
1383                 if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1384                     vendor_type == WPA_GET_BE32(&pos[2]))
1385                         wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1386                 pos += 2 + pos[1];
1387         }
1388
1389         if (wpabuf_len(buf) == 0) {
1390                 wpabuf_free(buf);
1391                 buf = NULL;
1392         }
1393
1394         return buf;
1395 }
1396
1397
1398 /*
1399  * Channels with a great SNR can operate at full rate. What is a great SNR?
1400  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1401  * rule of thumb is that any SNR above 20 is good." This one
1402  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1403  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1404  * conservative value.
1405  */
1406 #define GREAT_SNR 30
1407
1408 /* Compare function for sorting scan results. Return >0 if @b is considered
1409  * better. */
1410 static int wpa_scan_result_compar(const void *a, const void *b)
1411 {
1412 #define IS_5GHZ(n) (n > 4000)
1413 #define MIN(a,b) a < b ? a : b
1414         struct wpa_scan_res **_wa = (void *) a;
1415         struct wpa_scan_res **_wb = (void *) b;
1416         struct wpa_scan_res *wa = *_wa;
1417         struct wpa_scan_res *wb = *_wb;
1418         int wpa_a, wpa_b, maxrate_a, maxrate_b;
1419         int snr_a, snr_b;
1420
1421         /* WPA/WPA2 support preferred */
1422         wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1423                 wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1424         wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1425                 wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1426
1427         if (wpa_b && !wpa_a)
1428                 return 1;
1429         if (!wpa_b && wpa_a)
1430                 return -1;
1431
1432         /* privacy support preferred */
1433         if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1434             (wb->caps & IEEE80211_CAP_PRIVACY))
1435                 return 1;
1436         if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1437             (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1438                 return -1;
1439
1440         if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
1441             !((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
1442                 snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
1443                 snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
1444         } else {
1445                 /* Not suitable information to calculate SNR, so use level */
1446                 snr_a = wa->level;
1447                 snr_b = wb->level;
1448         }
1449
1450         /* best/max rate preferred if SNR close enough */
1451         if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1452             (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1453                 maxrate_a = wpa_scan_get_max_rate(wa);
1454                 maxrate_b = wpa_scan_get_max_rate(wb);
1455                 if (maxrate_a != maxrate_b)
1456                         return maxrate_b - maxrate_a;
1457                 if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1458                         return IS_5GHZ(wa->freq) ? -1 : 1;
1459         }
1460
1461         /* use freq for channel preference */
1462
1463         /* all things being equal, use SNR; if SNRs are
1464          * identical, use quality values since some drivers may only report
1465          * that value and leave the signal level zero */
1466         if (snr_b == snr_a)
1467                 return wb->qual - wa->qual;
1468         return snr_b - snr_a;
1469 #undef MIN
1470 #undef IS_5GHZ
1471 }
1472
1473
1474 #ifdef CONFIG_WPS
1475 /* Compare function for sorting scan results when searching a WPS AP for
1476  * provisioning. Return >0 if @b is considered better. */
1477 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1478 {
1479         struct wpa_scan_res **_wa = (void *) a;
1480         struct wpa_scan_res **_wb = (void *) b;
1481         struct wpa_scan_res *wa = *_wa;
1482         struct wpa_scan_res *wb = *_wb;
1483         int uses_wps_a, uses_wps_b;
1484         struct wpabuf *wps_a, *wps_b;
1485         int res;
1486
1487         /* Optimization - check WPS IE existence before allocated memory and
1488          * doing full reassembly. */
1489         uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1490         uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1491         if (uses_wps_a && !uses_wps_b)
1492                 return -1;
1493         if (!uses_wps_a && uses_wps_b)
1494                 return 1;
1495
1496         if (uses_wps_a && uses_wps_b) {
1497                 wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1498                 wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1499                 res = wps_ap_priority_compar(wps_a, wps_b);
1500                 wpabuf_free(wps_a);
1501                 wpabuf_free(wps_b);
1502                 if (res)
1503                         return res;
1504         }
1505
1506         /*
1507          * Do not use current AP security policy as a sorting criteria during
1508          * WPS provisioning step since the AP may get reconfigured at the
1509          * completion of provisioning.
1510          */
1511
1512         /* all things being equal, use signal level; if signal levels are
1513          * identical, use quality values since some drivers may only report
1514          * that value and leave the signal level zero */
1515         if (wb->level == wa->level)
1516                 return wb->qual - wa->qual;
1517         return wb->level - wa->level;
1518 }
1519 #endif /* CONFIG_WPS */
1520
1521
1522 static void dump_scan_res(struct wpa_scan_results *scan_res)
1523 {
1524 #ifndef CONFIG_NO_STDOUT_DEBUG
1525         size_t i;
1526
1527         if (scan_res->res == NULL || scan_res->num == 0)
1528                 return;
1529
1530         wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1531
1532         for (i = 0; i < scan_res->num; i++) {
1533                 struct wpa_scan_res *r = scan_res->res[i];
1534                 u8 *pos;
1535                 if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
1536                     == WPA_SCAN_LEVEL_DBM) {
1537                         int snr = r->level - r->noise;
1538                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1539                                    "noise=%d level=%d snr=%d%s flags=0x%x "
1540                                    "age=%u",
1541                                    MAC2STR(r->bssid), r->freq, r->qual,
1542                                    r->noise, r->level, snr,
1543                                    snr >= GREAT_SNR ? "*" : "", r->flags,
1544                                    r->age);
1545                 } else {
1546                         wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1547                                    "noise=%d level=%d flags=0x%x age=%u",
1548                                    MAC2STR(r->bssid), r->freq, r->qual,
1549                                    r->noise, r->level, r->flags, r->age);
1550                 }
1551                 pos = (u8 *) (r + 1);
1552                 if (r->ie_len)
1553                         wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1554                 pos += r->ie_len;
1555                 if (r->beacon_ie_len)
1556                         wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1557                                     pos, r->beacon_ie_len);
1558         }
1559 #endif /* CONFIG_NO_STDOUT_DEBUG */
1560 }
1561
1562
1563 /**
1564  * wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
1565  * @wpa_s: Pointer to wpa_supplicant data
1566  * @bssid: BSSID to check
1567  * Returns: 0 if the BSSID is filtered or 1 if not
1568  *
1569  * This function is used to filter out specific BSSIDs from scan reslts mainly
1570  * for testing purposes (SET bssid_filter ctrl_iface command).
1571  */
1572 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1573                                       const u8 *bssid)
1574 {
1575         size_t i;
1576
1577         if (wpa_s->bssid_filter == NULL)
1578                 return 1;
1579
1580         for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1581                 if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1582                               ETH_ALEN) == 0)
1583                         return 1;
1584         }
1585
1586         return 0;
1587 }
1588
1589
1590 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1591                             struct wpa_scan_results *res)
1592 {
1593         size_t i, j;
1594
1595         if (wpa_s->bssid_filter == NULL)
1596                 return;
1597
1598         for (i = 0, j = 0; i < res->num; i++) {
1599                 if (wpa_supplicant_filter_bssid_match(wpa_s,
1600                                                       res->res[i]->bssid)) {
1601                         res->res[j++] = res->res[i];
1602                 } else {
1603                         os_free(res->res[i]);
1604                         res->res[i] = NULL;
1605                 }
1606         }
1607
1608         if (res->num != j) {
1609                 wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1610                            (int) (res->num - j));
1611                 res->num = j;
1612         }
1613 }
1614
1615
1616 /**
1617  * wpa_supplicant_get_scan_results - Get scan results
1618  * @wpa_s: Pointer to wpa_supplicant data
1619  * @info: Information about what was scanned or %NULL if not available
1620  * @new_scan: Whether a new scan was performed
1621  * Returns: Scan results, %NULL on failure
1622  *
1623  * This function request the current scan results from the driver and updates
1624  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
1625  * results with wpa_scan_results_free().
1626  */
1627 struct wpa_scan_results *
1628 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
1629                                 struct scan_info *info, int new_scan)
1630 {
1631         struct wpa_scan_results *scan_res;
1632         size_t i;
1633         int (*compar)(const void *, const void *) = wpa_scan_result_compar;
1634
1635         scan_res = wpa_drv_get_scan_results2(wpa_s);
1636         if (scan_res == NULL) {
1637                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
1638                 return NULL;
1639         }
1640         if (scan_res->fetch_time.sec == 0) {
1641                 /*
1642                  * Make sure we have a valid timestamp if the driver wrapper
1643                  * does not set this.
1644                  */
1645                 os_get_reltime(&scan_res->fetch_time);
1646         }
1647         filter_scan_res(wpa_s, scan_res);
1648
1649 #ifdef CONFIG_WPS
1650         if (wpas_wps_searching(wpa_s)) {
1651                 wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
1652                         "provisioning rules");
1653                 compar = wpa_scan_result_wps_compar;
1654         }
1655 #endif /* CONFIG_WPS */
1656
1657         qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
1658               compar);
1659         dump_scan_res(scan_res);
1660
1661         wpa_bss_update_start(wpa_s);
1662         for (i = 0; i < scan_res->num; i++)
1663                 wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
1664                                         &scan_res->fetch_time);
1665         wpa_bss_update_end(wpa_s, info, new_scan);
1666
1667         return scan_res;
1668 }
1669
1670
1671 /**
1672  * wpa_supplicant_update_scan_results - Update scan results from the driver
1673  * @wpa_s: Pointer to wpa_supplicant data
1674  * Returns: 0 on success, -1 on failure
1675  *
1676  * This function updates the BSS table within wpa_supplicant based on the
1677  * currently available scan results from the driver without requesting a new
1678  * scan. This is used in cases where the driver indicates an association
1679  * (including roaming within ESS) and wpa_supplicant does not yet have the
1680  * needed information to complete the connection (e.g., to perform validation
1681  * steps in 4-way handshake).
1682  */
1683 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
1684 {
1685         struct wpa_scan_results *scan_res;
1686         scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
1687         if (scan_res == NULL)
1688                 return -1;
1689         wpa_scan_results_free(scan_res);
1690
1691         return 0;
1692 }
1693
1694
1695 /**
1696  * scan_only_handler - Reports scan results
1697  */
1698 void scan_only_handler(struct wpa_supplicant *wpa_s,
1699                        struct wpa_scan_results *scan_res)
1700 {
1701         wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
1702         if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
1703             wpa_s->manual_scan_use_id && wpa_s->own_scan_running) {
1704                 wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS "id=%u",
1705                              wpa_s->manual_scan_id);
1706                 wpa_s->manual_scan_use_id = 0;
1707         } else {
1708                 wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
1709         }
1710         wpas_notify_scan_results(wpa_s);
1711         wpas_notify_scan_done(wpa_s, 1);
1712         if (wpa_s->scan_work) {
1713                 struct wpa_radio_work *work = wpa_s->scan_work;
1714                 wpa_s->scan_work = NULL;
1715                 radio_work_done(work);
1716         }
1717 }
1718
1719
1720 int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
1721 {
1722         return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
1723 }
1724
1725
1726 struct wpa_driver_scan_params *
1727 wpa_scan_clone_params(const struct wpa_driver_scan_params *src)
1728 {
1729         struct wpa_driver_scan_params *params;
1730         size_t i;
1731         u8 *n;
1732
1733         params = os_zalloc(sizeof(*params));
1734         if (params == NULL)
1735                 return NULL;
1736
1737         for (i = 0; i < src->num_ssids; i++) {
1738                 if (src->ssids[i].ssid) {
1739                         n = os_malloc(src->ssids[i].ssid_len);
1740                         if (n == NULL)
1741                                 goto failed;
1742                         os_memcpy(n, src->ssids[i].ssid,
1743                                   src->ssids[i].ssid_len);
1744                         params->ssids[i].ssid = n;
1745                         params->ssids[i].ssid_len = src->ssids[i].ssid_len;
1746                 }
1747         }
1748         params->num_ssids = src->num_ssids;
1749
1750         if (src->extra_ies) {
1751                 n = os_malloc(src->extra_ies_len);
1752                 if (n == NULL)
1753                         goto failed;
1754                 os_memcpy(n, src->extra_ies, src->extra_ies_len);
1755                 params->extra_ies = n;
1756                 params->extra_ies_len = src->extra_ies_len;
1757         }
1758
1759         if (src->freqs) {
1760                 int len = int_array_len(src->freqs);
1761                 params->freqs = os_malloc((len + 1) * sizeof(int));
1762                 if (params->freqs == NULL)
1763                         goto failed;
1764                 os_memcpy(params->freqs, src->freqs, (len + 1) * sizeof(int));
1765         }
1766
1767         if (src->filter_ssids) {
1768                 params->filter_ssids = os_malloc(sizeof(params->filter_ssids) *
1769                                                  src->num_filter_ssids);
1770                 if (params->filter_ssids == NULL)
1771                         goto failed;
1772                 os_memcpy(params->filter_ssids, src->filter_ssids,
1773                           sizeof(params->filter_ssids) * src->num_filter_ssids);
1774                 params->num_filter_ssids = src->num_filter_ssids;
1775         }
1776
1777         params->filter_rssi = src->filter_rssi;
1778         params->p2p_probe = src->p2p_probe;
1779         params->only_new_results = src->only_new_results;
1780
1781         return params;
1782
1783 failed:
1784         wpa_scan_free_params(params);
1785         return NULL;
1786 }
1787
1788
1789 void wpa_scan_free_params(struct wpa_driver_scan_params *params)
1790 {
1791         size_t i;
1792
1793         if (params == NULL)
1794                 return;
1795
1796         for (i = 0; i < params->num_ssids; i++)
1797                 os_free((u8 *) params->ssids[i].ssid);
1798         os_free((u8 *) params->extra_ies);
1799         os_free(params->freqs);
1800         os_free(params->filter_ssids);
1801         os_free(params);
1802 }