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 #include "mesh.h"
26 
27 
wpa_supplicant_gen_assoc_event(struct wpa_supplicant * wpa_s)28 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
29 {
30 	struct wpa_ssid *ssid;
31 	union wpa_event_data data;
32 
33 	ssid = wpa_supplicant_get_ssid(wpa_s);
34 	if (ssid == NULL)
35 		return;
36 
37 	if (wpa_s->current_ssid == NULL) {
38 		wpa_s->current_ssid = ssid;
39 		if (wpa_s->current_ssid != NULL)
40 			wpas_notify_network_changed(wpa_s);
41 	}
42 	wpa_supplicant_initiate_eapol(wpa_s);
43 	wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
44 		"network - generating associated event");
45 	os_memset(&data, 0, sizeof(data));
46 	wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
47 }
48 
49 
50 #ifdef CONFIG_WPS
wpas_wps_in_use(struct wpa_supplicant * wpa_s,enum wps_request_type * req_type)51 static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
52 			   enum wps_request_type *req_type)
53 {
54 	struct wpa_ssid *ssid;
55 	int wps = 0;
56 
57 	for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
58 		if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
59 			continue;
60 
61 		wps = 1;
62 		*req_type = wpas_wps_get_req_type(ssid);
63 		if (!ssid->eap.phase1)
64 			continue;
65 
66 		if (os_strstr(ssid->eap.phase1, "pbc=1"))
67 			return 2;
68 	}
69 
70 #ifdef CONFIG_P2P
71 	if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
72 	    !wpa_s->conf->p2p_disabled) {
73 		wpa_s->wps->dev.p2p = 1;
74 		if (!wps) {
75 			wps = 1;
76 			*req_type = WPS_REQ_ENROLLEE_INFO;
77 		}
78 	}
79 #endif /* CONFIG_P2P */
80 
81 	return wps;
82 }
83 #endif /* CONFIG_WPS */
84 
85 
86 /**
87  * wpa_supplicant_enabled_networks - Check whether there are enabled networks
88  * @wpa_s: Pointer to wpa_supplicant data
89  * Returns: 0 if no networks are enabled, >0 if networks are enabled
90  *
91  * This function is used to figure out whether any networks (or Interworking
92  * with enabled credentials and auto_interworking) are present in the current
93  * configuration.
94  */
wpa_supplicant_enabled_networks(struct wpa_supplicant * wpa_s)95 int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
96 {
97 	struct wpa_ssid *ssid = wpa_s->conf->ssid;
98 	int count = 0, disabled = 0;
99 
100 	if (wpa_s->p2p_mgmt)
101 		return 0; /* no normal network profiles on p2p_mgmt interface */
102 
103 	while (ssid) {
104 		if (!wpas_network_disabled(wpa_s, ssid))
105 			count++;
106 		else
107 			disabled++;
108 		ssid = ssid->next;
109 	}
110 	if (wpa_s->conf->cred && wpa_s->conf->interworking &&
111 	    wpa_s->conf->auto_interworking)
112 		count++;
113 	if (count == 0 && disabled > 0) {
114 		wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
115 			"networks)", disabled);
116 	}
117 	return count;
118 }
119 
120 
wpa_supplicant_assoc_try(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid)121 static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
122 				     struct wpa_ssid *ssid)
123 {
124 	while (ssid) {
125 		if (!wpas_network_disabled(wpa_s, ssid))
126 			break;
127 		ssid = ssid->next;
128 	}
129 
130 	/* ap_scan=2 mode - try to associate with each SSID. */
131 	if (ssid == NULL) {
132 		wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
133 			"end of scan list - go back to beginning");
134 		wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
135 		wpa_supplicant_req_scan(wpa_s, 0, 0);
136 		return;
137 	}
138 	if (ssid->next) {
139 		/* Continue from the next SSID on the next attempt. */
140 		wpa_s->prev_scan_ssid = ssid;
141 	} else {
142 		/* Start from the beginning of the SSID list. */
143 		wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
144 	}
145 	wpa_supplicant_associate(wpa_s, NULL, ssid);
146 }
147 
148 
wpas_trigger_scan_cb(struct wpa_radio_work * work,int deinit)149 static void wpas_trigger_scan_cb(struct wpa_radio_work *work, int deinit)
150 {
151 	struct wpa_supplicant *wpa_s = work->wpa_s;
152 	struct wpa_driver_scan_params *params = work->ctx;
153 	int ret;
154 
155 	if (deinit) {
156 		if (!work->started) {
157 			wpa_scan_free_params(params);
158 			return;
159 		}
160 		wpa_supplicant_notify_scanning(wpa_s, 0);
161 		wpas_notify_scan_done(wpa_s, 0);
162 		wpa_s->scan_work = NULL;
163 		return;
164 	}
165 
166 	if (wpas_update_random_addr_disassoc(wpa_s) < 0) {
167 		wpa_msg(wpa_s, MSG_INFO,
168 			"Failed to assign random MAC address for a scan");
169 		radio_work_done(work);
170 		return;
171 	}
172 
173 	wpa_supplicant_notify_scanning(wpa_s, 1);
174 
175 	if (wpa_s->clear_driver_scan_cache) {
176 		wpa_printf(MSG_DEBUG,
177 			   "Request driver to clear scan cache due to local BSS flush");
178 		params->only_new_results = 1;
179 	}
180 	ret = wpa_drv_scan(wpa_s, params);
181 	wpa_scan_free_params(params);
182 	work->ctx = NULL;
183 	if (ret) {
184 		int retry = wpa_s->last_scan_req != MANUAL_SCAN_REQ;
185 
186 		if (wpa_s->disconnected)
187 			retry = 0;
188 
189 		wpa_supplicant_notify_scanning(wpa_s, 0);
190 		wpas_notify_scan_done(wpa_s, 0);
191 		if (wpa_s->wpa_state == WPA_SCANNING)
192 			wpa_supplicant_set_state(wpa_s,
193 						 wpa_s->scan_prev_wpa_state);
194 		wpa_msg(wpa_s, MSG_INFO, WPA_EVENT_SCAN_FAILED "ret=%d%s",
195 			ret, retry ? " retry=1" : "");
196 		radio_work_done(work);
197 
198 		if (retry) {
199 			/* Restore scan_req since we will try to scan again */
200 			wpa_s->scan_req = wpa_s->last_scan_req;
201 			wpa_supplicant_req_scan(wpa_s, 1, 0);
202 		}
203 		return;
204 	}
205 
206 	os_get_reltime(&wpa_s->scan_trigger_time);
207 	wpa_s->scan_runs++;
208 	wpa_s->normal_scans++;
209 	wpa_s->own_scan_requested = 1;
210 	wpa_s->clear_driver_scan_cache = 0;
211 	wpa_s->scan_work = work;
212 }
213 
214 
215 /**
216  * wpa_supplicant_trigger_scan - Request driver to start a scan
217  * @wpa_s: Pointer to wpa_supplicant data
218  * @params: Scan parameters
219  * Returns: 0 on success, -1 on failure
220  */
wpa_supplicant_trigger_scan(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params)221 int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
222 				struct wpa_driver_scan_params *params)
223 {
224 	struct wpa_driver_scan_params *ctx;
225 
226 	if (wpa_s->scan_work) {
227 		wpa_dbg(wpa_s, MSG_INFO, "Reject scan trigger since one is already pending");
228 		return -1;
229 	}
230 
231 	ctx = wpa_scan_clone_params(params);
232 	if (ctx == NULL)
233 		return -1;
234 
235 	if (radio_add_work(wpa_s, 0, "scan", 0, wpas_trigger_scan_cb, ctx) < 0)
236 	{
237 		wpa_scan_free_params(ctx);
238 		return -1;
239 	}
240 
241 	return 0;
242 }
243 
244 
245 static void
wpa_supplicant_delayed_sched_scan_timeout(void * eloop_ctx,void * timeout_ctx)246 wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
247 {
248 	struct wpa_supplicant *wpa_s = eloop_ctx;
249 
250 	wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
251 
252 	if (wpa_supplicant_req_sched_scan(wpa_s))
253 		wpa_supplicant_req_scan(wpa_s, 0, 0);
254 }
255 
256 
257 static void
wpa_supplicant_sched_scan_timeout(void * eloop_ctx,void * timeout_ctx)258 wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
259 {
260 	struct wpa_supplicant *wpa_s = eloop_ctx;
261 
262 	wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
263 
264 	wpa_s->sched_scan_timed_out = 1;
265 	wpa_supplicant_cancel_sched_scan(wpa_s);
266 }
267 
268 
wpa_supplicant_start_sched_scan(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params,int interval)269 int wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
270 				    struct wpa_driver_scan_params *params,
271 				    int interval)
272 {
273 	int ret;
274 
275 	wpa_supplicant_notify_scanning(wpa_s, 1);
276 	ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
277 	if (ret)
278 		wpa_supplicant_notify_scanning(wpa_s, 0);
279 	else
280 		wpa_s->sched_scanning = 1;
281 
282 	return ret;
283 }
284 
285 
wpa_supplicant_stop_sched_scan(struct wpa_supplicant * wpa_s)286 int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
287 {
288 	int ret;
289 
290 	ret = wpa_drv_stop_sched_scan(wpa_s);
291 	if (ret) {
292 		wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
293 		/* TODO: what to do if stopping fails? */
294 		return -1;
295 	}
296 
297 	return ret;
298 }
299 
300 
301 static struct wpa_driver_scan_filter *
wpa_supplicant_build_filter_ssids(struct wpa_config * conf,size_t * num_ssids)302 wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
303 {
304 	struct wpa_driver_scan_filter *ssids;
305 	struct wpa_ssid *ssid;
306 	size_t count;
307 
308 	*num_ssids = 0;
309 	if (!conf->filter_ssids)
310 		return NULL;
311 
312 	for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
313 		if (ssid->ssid && ssid->ssid_len)
314 			count++;
315 	}
316 	if (count == 0)
317 		return NULL;
318 	ssids = os_calloc(count, sizeof(struct wpa_driver_scan_filter));
319 	if (ssids == NULL)
320 		return NULL;
321 
322 	for (ssid = conf->ssid; ssid; ssid = ssid->next) {
323 		if (!ssid->ssid || !ssid->ssid_len)
324 			continue;
325 		os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
326 		ssids[*num_ssids].ssid_len = ssid->ssid_len;
327 		(*num_ssids)++;
328 	}
329 
330 	return ssids;
331 }
332 
333 
wpa_supplicant_optimize_freqs(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params)334 static void wpa_supplicant_optimize_freqs(
335 	struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
336 {
337 #ifdef CONFIG_P2P
338 	if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
339 	    wpa_s->go_params) {
340 		/* Optimize provisioning state scan based on GO information */
341 		if (wpa_s->p2p_in_provisioning < 5 &&
342 		    wpa_s->go_params->freq > 0) {
343 			wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
344 				"preferred frequency %d MHz",
345 				wpa_s->go_params->freq);
346 			params->freqs = os_calloc(2, sizeof(int));
347 			if (params->freqs)
348 				params->freqs[0] = wpa_s->go_params->freq;
349 		} else if (wpa_s->p2p_in_provisioning < 8 &&
350 			   wpa_s->go_params->freq_list[0]) {
351 			wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
352 				"channels");
353 			int_array_concat(&params->freqs,
354 					 wpa_s->go_params->freq_list);
355 			if (params->freqs)
356 				int_array_sort_unique(params->freqs);
357 		}
358 		wpa_s->p2p_in_provisioning++;
359 	}
360 
361 	if (params->freqs == NULL && wpa_s->p2p_in_invitation) {
362 		/*
363 		 * Optimize scan based on GO information during persistent
364 		 * group reinvocation
365 		 */
366 		if (wpa_s->p2p_in_invitation < 5 &&
367 		    wpa_s->p2p_invite_go_freq > 0) {
368 			wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO preferred frequency %d MHz during invitation",
369 				wpa_s->p2p_invite_go_freq);
370 			params->freqs = os_calloc(2, sizeof(int));
371 			if (params->freqs)
372 				params->freqs[0] = wpa_s->p2p_invite_go_freq;
373 		}
374 		wpa_s->p2p_in_invitation++;
375 		if (wpa_s->p2p_in_invitation > 20) {
376 			/*
377 			 * This should not really happen since the variable is
378 			 * cleared on group removal, but if it does happen, make
379 			 * sure we do not get stuck in special invitation scan
380 			 * mode.
381 			 */
382 			wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Clear p2p_in_invitation");
383 			wpa_s->p2p_in_invitation = 0;
384 		}
385 	}
386 #endif /* CONFIG_P2P */
387 
388 #ifdef CONFIG_WPS
389 	if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
390 		/*
391 		 * Optimize post-provisioning scan based on channel used
392 		 * during provisioning.
393 		 */
394 		wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
395 			"that was used during provisioning", wpa_s->wps_freq);
396 		params->freqs = os_calloc(2, sizeof(int));
397 		if (params->freqs)
398 			params->freqs[0] = wpa_s->wps_freq;
399 		wpa_s->after_wps--;
400 	} else if (wpa_s->after_wps)
401 		wpa_s->after_wps--;
402 
403 	if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
404 	{
405 		/* Optimize provisioning scan based on already known channel */
406 		wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
407 			wpa_s->wps_freq);
408 		params->freqs = os_calloc(2, sizeof(int));
409 		if (params->freqs)
410 			params->freqs[0] = wpa_s->wps_freq;
411 		wpa_s->known_wps_freq = 0; /* only do this once */
412 	}
413 #endif /* CONFIG_WPS */
414 }
415 
416 
417 #ifdef CONFIG_INTERWORKING
wpas_add_interworking_elements(struct wpa_supplicant * wpa_s,struct wpabuf * buf)418 static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
419 					   struct wpabuf *buf)
420 {
421 	wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
422 	wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
423 		      1 + ETH_ALEN);
424 	wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
425 	/* No Venue Info */
426 	if (!is_zero_ether_addr(wpa_s->conf->hessid))
427 		wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
428 }
429 #endif /* CONFIG_INTERWORKING */
430 
431 
wpa_supplicant_extra_ies(struct wpa_supplicant * wpa_s)432 static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
433 {
434 	struct wpabuf *extra_ie = NULL;
435 	u8 ext_capab[18];
436 	int ext_capab_len;
437 #ifdef CONFIG_WPS
438 	int wps = 0;
439 	enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
440 #endif /* CONFIG_WPS */
441 
442 	ext_capab_len = wpas_build_ext_capab(wpa_s, ext_capab,
443 					     sizeof(ext_capab));
444 	if (ext_capab_len > 0 &&
445 	    wpabuf_resize(&extra_ie, ext_capab_len) == 0)
446 		wpabuf_put_data(extra_ie, ext_capab, ext_capab_len);
447 
448 #ifdef CONFIG_INTERWORKING
449 	if (wpa_s->conf->interworking &&
450 	    wpabuf_resize(&extra_ie, 100) == 0)
451 		wpas_add_interworking_elements(wpa_s, extra_ie);
452 #endif /* CONFIG_INTERWORKING */
453 
454 #ifdef CONFIG_WPS
455 	wps = wpas_wps_in_use(wpa_s, &req_type);
456 
457 	if (wps) {
458 		struct wpabuf *wps_ie;
459 		wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
460 						DEV_PW_DEFAULT,
461 						&wpa_s->wps->dev,
462 						wpa_s->wps->uuid, req_type,
463 						0, NULL);
464 		if (wps_ie) {
465 			if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
466 				wpabuf_put_buf(extra_ie, wps_ie);
467 			wpabuf_free(wps_ie);
468 		}
469 	}
470 
471 #ifdef CONFIG_P2P
472 	if (wps) {
473 		size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
474 		if (wpabuf_resize(&extra_ie, ielen) == 0)
475 			wpas_p2p_scan_ie(wpa_s, extra_ie);
476 	}
477 #endif /* CONFIG_P2P */
478 
479 	wpa_supplicant_mesh_add_scan_ie(wpa_s, &extra_ie);
480 
481 #endif /* CONFIG_WPS */
482 
483 #ifdef CONFIG_HS20
484 	if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
485 		wpas_hs20_add_indication(extra_ie, -1);
486 #endif /* CONFIG_HS20 */
487 
488 	return extra_ie;
489 }
490 
491 
492 #ifdef CONFIG_P2P
493 
494 /*
495  * Check whether there are any enabled networks or credentials that could be
496  * used for a non-P2P connection.
497  */
non_p2p_network_enabled(struct wpa_supplicant * wpa_s)498 static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
499 {
500 	struct wpa_ssid *ssid;
501 
502 	for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
503 		if (wpas_network_disabled(wpa_s, ssid))
504 			continue;
505 		if (!ssid->p2p_group)
506 			return 1;
507 	}
508 
509 	if (wpa_s->conf->cred && wpa_s->conf->interworking &&
510 	    wpa_s->conf->auto_interworking)
511 		return 1;
512 
513 	return 0;
514 }
515 
516 #endif /* CONFIG_P2P */
517 
518 
get_mode(struct hostapd_hw_modes * modes,u16 num_modes,enum hostapd_hw_mode mode)519 static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
520 					  u16 num_modes,
521 					  enum hostapd_hw_mode mode)
522 {
523 	u16 i;
524 
525 	for (i = 0; i < num_modes; i++) {
526 		if (modes[i].mode == mode)
527 			return &modes[i];
528 	}
529 
530 	return NULL;
531 }
532 
533 
wpa_setband_scan_freqs_list(struct wpa_supplicant * wpa_s,enum hostapd_hw_mode band,struct wpa_driver_scan_params * params)534 static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
535 					enum hostapd_hw_mode band,
536 					struct wpa_driver_scan_params *params)
537 {
538 	/* Include only supported channels for the specified band */
539 	struct hostapd_hw_modes *mode;
540 	int count, i;
541 
542 	mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
543 	if (mode == NULL) {
544 		/* No channels supported in this band - use empty list */
545 		params->freqs = os_zalloc(sizeof(int));
546 		return;
547 	}
548 
549 	params->freqs = os_calloc(mode->num_channels + 1, sizeof(int));
550 	if (params->freqs == NULL)
551 		return;
552 	for (count = 0, i = 0; i < mode->num_channels; i++) {
553 		if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
554 			continue;
555 		params->freqs[count++] = mode->channels[i].freq;
556 	}
557 }
558 
559 
wpa_setband_scan_freqs(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params)560 static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
561 				   struct wpa_driver_scan_params *params)
562 {
563 	if (wpa_s->hw.modes == NULL)
564 		return; /* unknown what channels the driver supports */
565 	if (params->freqs)
566 		return; /* already using a limited channel set */
567 	if (wpa_s->setband == WPA_SETBAND_5G)
568 		wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
569 					    params);
570 	else if (wpa_s->setband == WPA_SETBAND_2G)
571 		wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
572 					    params);
573 }
574 
575 
wpa_set_scan_ssids(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params,size_t max_ssids)576 static void wpa_set_scan_ssids(struct wpa_supplicant *wpa_s,
577 			       struct wpa_driver_scan_params *params,
578 			       size_t max_ssids)
579 {
580 	unsigned int i;
581 	struct wpa_ssid *ssid;
582 
583 	for (i = 0; i < wpa_s->scan_id_count; i++) {
584 		unsigned int j;
585 
586 		ssid = wpa_config_get_network(wpa_s->conf, wpa_s->scan_id[i]);
587 		if (!ssid || !ssid->scan_ssid)
588 			continue;
589 
590 		for (j = 0; j < params->num_ssids; j++) {
591 			if (params->ssids[j].ssid_len == ssid->ssid_len &&
592 			    params->ssids[j].ssid &&
593 			    os_memcmp(params->ssids[j].ssid, ssid->ssid,
594 				      ssid->ssid_len) == 0)
595 				break;
596 		}
597 		if (j < params->num_ssids)
598 			continue; /* already in the list */
599 
600 		if (params->num_ssids + 1 > max_ssids) {
601 			wpa_printf(MSG_DEBUG,
602 				   "Over max scan SSIDs for manual request");
603 			break;
604 		}
605 
606 		wpa_printf(MSG_DEBUG, "Scan SSID (manual request): %s",
607 			   wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
608 		params->ssids[params->num_ssids].ssid = ssid->ssid;
609 		params->ssids[params->num_ssids].ssid_len = ssid->ssid_len;
610 		params->num_ssids++;
611 	}
612 
613 	wpa_s->scan_id_count = 0;
614 }
615 
616 
wpa_set_ssids_from_scan_req(struct wpa_supplicant * wpa_s,struct wpa_driver_scan_params * params,size_t max_ssids)617 static int wpa_set_ssids_from_scan_req(struct wpa_supplicant *wpa_s,
618 				       struct wpa_driver_scan_params *params,
619 				       size_t max_ssids)
620 {
621 	unsigned int i;
622 
623 	if (wpa_s->ssids_from_scan_req == NULL ||
624 	    wpa_s->num_ssids_from_scan_req == 0)
625 		return 0;
626 
627 	if (wpa_s->num_ssids_from_scan_req > max_ssids) {
628 		wpa_s->num_ssids_from_scan_req = max_ssids;
629 		wpa_printf(MSG_DEBUG, "Over max scan SSIDs from scan req: %u",
630 			   (unsigned int) max_ssids);
631 	}
632 
633 	for (i = 0; i < wpa_s->num_ssids_from_scan_req; i++) {
634 		params->ssids[i].ssid = wpa_s->ssids_from_scan_req[i].ssid;
635 		params->ssids[i].ssid_len =
636 			wpa_s->ssids_from_scan_req[i].ssid_len;
637 		wpa_hexdump_ascii(MSG_DEBUG, "specific SSID",
638 				  params->ssids[i].ssid,
639 				  params->ssids[i].ssid_len);
640 	}
641 
642 	params->num_ssids = wpa_s->num_ssids_from_scan_req;
643 	wpa_s->num_ssids_from_scan_req = 0;
644 	return 1;
645 }
646 
647 
wpa_supplicant_scan(void * eloop_ctx,void * timeout_ctx)648 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
649 {
650 	struct wpa_supplicant *wpa_s = eloop_ctx;
651 	struct wpa_ssid *ssid;
652 	int ret, p2p_in_prog;
653 	struct wpabuf *extra_ie = NULL;
654 	struct wpa_driver_scan_params params;
655 	struct wpa_driver_scan_params *scan_params;
656 	size_t max_ssids;
657 	int connect_without_scan = 0;
658 
659 	if (wpa_s->pno || wpa_s->pno_sched_pending) {
660 		wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - PNO is in progress");
661 		return;
662 	}
663 
664 	if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
665 		wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
666 		return;
667 	}
668 
669 	if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
670 		wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
671 		wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
672 		return;
673 	}
674 
675 	if (wpa_s->scanning) {
676 		/*
677 		 * If we are already in scanning state, we shall reschedule the
678 		 * the incoming scan request.
679 		 */
680 		wpa_dbg(wpa_s, MSG_DEBUG, "Already scanning - Reschedule the incoming scan req");
681 		wpa_supplicant_req_scan(wpa_s, 1, 0);
682 		return;
683 	}
684 
685 	if (!wpa_supplicant_enabled_networks(wpa_s) &&
686 	    wpa_s->scan_req == NORMAL_SCAN_REQ) {
687 		wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
688 		wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
689 		return;
690 	}
691 
692 	if (wpa_s->conf->ap_scan != 0 &&
693 	    (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
694 		wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
695 			"overriding ap_scan configuration");
696 		wpa_s->conf->ap_scan = 0;
697 		wpas_notify_ap_scan_changed(wpa_s);
698 	}
699 
700 	if (wpa_s->conf->ap_scan == 0) {
701 		wpa_supplicant_gen_assoc_event(wpa_s);
702 		return;
703 	}
704 
705 	ssid = NULL;
706 	if (wpa_s->scan_req != MANUAL_SCAN_REQ &&
707 	    wpa_s->connect_without_scan) {
708 		connect_without_scan = 1;
709 		for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
710 			if (ssid == wpa_s->connect_without_scan)
711 				break;
712 		}
713 	}
714 
715 	p2p_in_prog = wpas_p2p_in_progress(wpa_s);
716 	if (p2p_in_prog && p2p_in_prog != 2 &&
717 	    (!ssid ||
718 	     (ssid->mode != WPAS_MODE_AP && ssid->mode != WPAS_MODE_P2P_GO))) {
719 		wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan while P2P operation is in progress");
720 		wpa_supplicant_req_scan(wpa_s, 5, 0);
721 		return;
722 	}
723 
724 	if (wpa_s->conf->ap_scan == 2)
725 		max_ssids = 1;
726 	else {
727 		max_ssids = wpa_s->max_scan_ssids;
728 		if (max_ssids > WPAS_MAX_SCAN_SSIDS)
729 			max_ssids = WPAS_MAX_SCAN_SSIDS;
730 	}
731 
732 	wpa_s->last_scan_req = wpa_s->scan_req;
733 	wpa_s->scan_req = NORMAL_SCAN_REQ;
734 
735 	if (connect_without_scan) {
736 		wpa_s->connect_without_scan = NULL;
737 		if (ssid) {
738 			wpa_printf(MSG_DEBUG, "Start a pre-selected network "
739 				   "without scan step");
740 			wpa_supplicant_associate(wpa_s, NULL, ssid);
741 			return;
742 		}
743 	}
744 
745 	os_memset(&params, 0, sizeof(params));
746 
747 	wpa_s->scan_prev_wpa_state = wpa_s->wpa_state;
748 	if (wpa_s->wpa_state == WPA_DISCONNECTED ||
749 	    wpa_s->wpa_state == WPA_INACTIVE)
750 		wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
751 
752 	/*
753 	 * If autoscan has set its own scanning parameters
754 	 */
755 	if (wpa_s->autoscan_params != NULL) {
756 		scan_params = wpa_s->autoscan_params;
757 		goto scan;
758 	}
759 
760 	if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
761 	    wpa_set_ssids_from_scan_req(wpa_s, &params, max_ssids)) {
762 		wpa_printf(MSG_DEBUG, "Use specific SSIDs from SCAN command");
763 		goto ssid_list_set;
764 	}
765 
766 #ifdef CONFIG_P2P
767 	if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
768 	    wpa_s->go_params && !wpa_s->conf->passive_scan) {
769 		wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during P2P group formation (p2p_in_provisioning=%d show_group_started=%d)",
770 			   wpa_s->p2p_in_provisioning,
771 			   wpa_s->show_group_started);
772 		params.ssids[0].ssid = wpa_s->go_params->ssid;
773 		params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
774 		params.num_ssids = 1;
775 		goto ssid_list_set;
776 	}
777 
778 	if (wpa_s->p2p_in_invitation) {
779 		if (wpa_s->current_ssid) {
780 			wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during invitation");
781 			params.ssids[0].ssid = wpa_s->current_ssid->ssid;
782 			params.ssids[0].ssid_len =
783 				wpa_s->current_ssid->ssid_len;
784 			params.num_ssids = 1;
785 		} else {
786 			wpa_printf(MSG_DEBUG, "P2P: No specific SSID known for scan during invitation");
787 		}
788 		goto ssid_list_set;
789 	}
790 #endif /* CONFIG_P2P */
791 
792 	/* Find the starting point from which to continue scanning */
793 	ssid = wpa_s->conf->ssid;
794 	if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
795 		while (ssid) {
796 			if (ssid == wpa_s->prev_scan_ssid) {
797 				ssid = ssid->next;
798 				break;
799 			}
800 			ssid = ssid->next;
801 		}
802 	}
803 
804 	if (wpa_s->last_scan_req != MANUAL_SCAN_REQ &&
805 	    wpa_s->conf->ap_scan == 2) {
806 		wpa_s->connect_without_scan = NULL;
807 		wpa_s->prev_scan_wildcard = 0;
808 		wpa_supplicant_assoc_try(wpa_s, ssid);
809 		return;
810 	} else if (wpa_s->conf->ap_scan == 2) {
811 		/*
812 		 * User-initiated scan request in ap_scan == 2; scan with
813 		 * wildcard SSID.
814 		 */
815 		ssid = NULL;
816 	} else if (wpa_s->reattach && wpa_s->current_ssid != NULL) {
817 		/*
818 		 * Perform single-channel single-SSID scan for
819 		 * reassociate-to-same-BSS operation.
820 		 */
821 		/* Setup SSID */
822 		ssid = wpa_s->current_ssid;
823 		wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
824 				  ssid->ssid, ssid->ssid_len);
825 		params.ssids[0].ssid = ssid->ssid;
826 		params.ssids[0].ssid_len = ssid->ssid_len;
827 		params.num_ssids = 1;
828 
829 		/*
830 		 * Allocate memory for frequency array, allocate one extra
831 		 * slot for the zero-terminator.
832 		 */
833 		params.freqs = os_malloc(sizeof(int) * 2);
834 		if (params.freqs == NULL) {
835 			wpa_dbg(wpa_s, MSG_ERROR, "Memory allocation failed");
836 			return;
837 		}
838 		params.freqs[0] = wpa_s->assoc_freq;
839 		params.freqs[1] = 0;
840 
841 		/*
842 		 * Reset the reattach flag so that we fall back to full scan if
843 		 * this scan fails.
844 		 */
845 		wpa_s->reattach = 0;
846 	} else {
847 		struct wpa_ssid *start = ssid, *tssid;
848 		int freqs_set = 0;
849 		if (ssid == NULL && max_ssids > 1)
850 			ssid = wpa_s->conf->ssid;
851 		while (ssid) {
852 			if (!wpas_network_disabled(wpa_s, ssid) &&
853 			    ssid->scan_ssid) {
854 				wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
855 						  ssid->ssid, ssid->ssid_len);
856 				params.ssids[params.num_ssids].ssid =
857 					ssid->ssid;
858 				params.ssids[params.num_ssids].ssid_len =
859 					ssid->ssid_len;
860 				params.num_ssids++;
861 				if (params.num_ssids + 1 >= max_ssids)
862 					break;
863 			}
864 			ssid = ssid->next;
865 			if (ssid == start)
866 				break;
867 			if (ssid == NULL && max_ssids > 1 &&
868 			    start != wpa_s->conf->ssid)
869 				ssid = wpa_s->conf->ssid;
870 		}
871 
872 		if (wpa_s->scan_id_count &&
873 		    wpa_s->last_scan_req == MANUAL_SCAN_REQ)
874 			wpa_set_scan_ssids(wpa_s, &params, max_ssids);
875 
876 		for (tssid = wpa_s->conf->ssid;
877 		     wpa_s->last_scan_req != MANUAL_SCAN_REQ && tssid;
878 		     tssid = tssid->next) {
879 			if (wpas_network_disabled(wpa_s, tssid))
880 				continue;
881 			if ((params.freqs || !freqs_set) && tssid->scan_freq) {
882 				int_array_concat(&params.freqs,
883 						 tssid->scan_freq);
884 			} else {
885 				os_free(params.freqs);
886 				params.freqs = NULL;
887 			}
888 			freqs_set = 1;
889 		}
890 		int_array_sort_unique(params.freqs);
891 	}
892 
893 	if (ssid && max_ssids == 1) {
894 		/*
895 		 * If the driver is limited to 1 SSID at a time interleave
896 		 * wildcard SSID scans with specific SSID scans to avoid
897 		 * waiting a long time for a wildcard scan.
898 		 */
899 		if (!wpa_s->prev_scan_wildcard) {
900 			params.ssids[0].ssid = NULL;
901 			params.ssids[0].ssid_len = 0;
902 			wpa_s->prev_scan_wildcard = 1;
903 			wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
904 				"wildcard SSID (Interleave with specific)");
905 		} else {
906 			wpa_s->prev_scan_ssid = ssid;
907 			wpa_s->prev_scan_wildcard = 0;
908 			wpa_dbg(wpa_s, MSG_DEBUG,
909 				"Starting AP scan for specific SSID: %s",
910 				wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
911 		}
912 	} else if (ssid) {
913 		/* max_ssids > 1 */
914 
915 		wpa_s->prev_scan_ssid = ssid;
916 		wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
917 			"the scan request");
918 		params.num_ssids++;
919 	} else if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
920 		   wpa_s->manual_scan_passive && params.num_ssids == 0) {
921 		wpa_dbg(wpa_s, MSG_DEBUG, "Use passive scan based on manual request");
922 	} else if (wpa_s->conf->passive_scan) {
923 		wpa_dbg(wpa_s, MSG_DEBUG,
924 			"Use passive scan based on configuration");
925 	} else {
926 		wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
927 		params.num_ssids++;
928 		wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
929 			"SSID");
930 	}
931 
932 ssid_list_set:
933 	wpa_supplicant_optimize_freqs(wpa_s, &params);
934 	extra_ie = wpa_supplicant_extra_ies(wpa_s);
935 
936 	if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
937 	    wpa_s->manual_scan_only_new) {
938 		wpa_printf(MSG_DEBUG,
939 			   "Request driver to clear scan cache due to manual only_new=1 scan");
940 		params.only_new_results = 1;
941 	}
942 
943 	if (wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs == NULL &&
944 	    wpa_s->manual_scan_freqs) {
945 		wpa_dbg(wpa_s, MSG_DEBUG, "Limit manual scan to specified channels");
946 		params.freqs = wpa_s->manual_scan_freqs;
947 		wpa_s->manual_scan_freqs = NULL;
948 	}
949 
950 	if (params.freqs == NULL && wpa_s->next_scan_freqs) {
951 		wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
952 			"generated frequency list");
953 		params.freqs = wpa_s->next_scan_freqs;
954 	} else
955 		os_free(wpa_s->next_scan_freqs);
956 	wpa_s->next_scan_freqs = NULL;
957 	wpa_setband_scan_freqs(wpa_s, &params);
958 
959 	/* See if user specified frequencies. If so, scan only those. */
960 	if (wpa_s->conf->freq_list && !params.freqs) {
961 		wpa_dbg(wpa_s, MSG_DEBUG,
962 			"Optimize scan based on conf->freq_list");
963 		int_array_concat(&params.freqs, wpa_s->conf->freq_list);
964 	}
965 
966 	/* Use current associated channel? */
967 	if (wpa_s->conf->scan_cur_freq && !params.freqs) {
968 		unsigned int num = wpa_s->num_multichan_concurrent;
969 
970 		params.freqs = os_calloc(num + 1, sizeof(int));
971 		if (params.freqs) {
972 			num = get_shared_radio_freqs(wpa_s, params.freqs, num);
973 			if (num > 0) {
974 				wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the "
975 					"current operating channels since "
976 					"scan_cur_freq is enabled");
977 			} else {
978 				os_free(params.freqs);
979 				params.freqs = NULL;
980 			}
981 		}
982 	}
983 
984 	params.filter_ssids = wpa_supplicant_build_filter_ssids(
985 		wpa_s->conf, &params.num_filter_ssids);
986 	if (extra_ie) {
987 		params.extra_ies = wpabuf_head(extra_ie);
988 		params.extra_ies_len = wpabuf_len(extra_ie);
989 	}
990 
991 #ifdef CONFIG_P2P
992 	if (wpa_s->p2p_in_provisioning || wpa_s->p2p_in_invitation ||
993 	    (wpa_s->show_group_started && wpa_s->go_params)) {
994 		/*
995 		 * The interface may not yet be in P2P mode, so we have to
996 		 * explicitly request P2P probe to disable CCK rates.
997 		 */
998 		params.p2p_probe = 1;
999 	}
1000 #endif /* CONFIG_P2P */
1001 
1002 	if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_SCAN) {
1003 		params.mac_addr_rand = 1;
1004 		if (wpa_s->mac_addr_scan) {
1005 			params.mac_addr = wpa_s->mac_addr_scan;
1006 			params.mac_addr_mask = wpa_s->mac_addr_scan + ETH_ALEN;
1007 		}
1008 	}
1009 
1010 	scan_params = &params;
1011 
1012 scan:
1013 #ifdef CONFIG_P2P
1014 	/*
1015 	 * If the driver does not support multi-channel concurrency and a
1016 	 * virtual interface that shares the same radio with the wpa_s interface
1017 	 * is operating there may not be need to scan other channels apart from
1018 	 * the current operating channel on the other virtual interface. Filter
1019 	 * out other channels in case we are trying to find a connection for a
1020 	 * station interface when we are not configured to prefer station
1021 	 * connection and a concurrent operation is already in process.
1022 	 */
1023 	if (wpa_s->scan_for_connection &&
1024 	    wpa_s->last_scan_req == NORMAL_SCAN_REQ &&
1025 	    !scan_params->freqs && !params.freqs &&
1026 	    wpas_is_p2p_prioritized(wpa_s) &&
1027 	    wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
1028 	    non_p2p_network_enabled(wpa_s)) {
1029 		unsigned int num = wpa_s->num_multichan_concurrent;
1030 
1031 		params.freqs = os_calloc(num + 1, sizeof(int));
1032 		if (params.freqs) {
1033 			num = get_shared_radio_freqs(wpa_s, params.freqs, num);
1034 			if (num > 0 && num == wpa_s->num_multichan_concurrent) {
1035 				wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current operating channels since all channels are already used");
1036 			} else {
1037 				os_free(params.freqs);
1038 				params.freqs = NULL;
1039 			}
1040 		}
1041 	}
1042 #endif /* CONFIG_P2P */
1043 
1044 	ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
1045 
1046 	if (ret && wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs &&
1047 	    !wpa_s->manual_scan_freqs) {
1048 		/* Restore manual_scan_freqs for the next attempt */
1049 		wpa_s->manual_scan_freqs = params.freqs;
1050 		params.freqs = NULL;
1051 	}
1052 
1053 	wpabuf_free(extra_ie);
1054 	os_free(params.freqs);
1055 	os_free(params.filter_ssids);
1056 
1057 	if (ret) {
1058 		wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
1059 		if (wpa_s->scan_prev_wpa_state != wpa_s->wpa_state)
1060 			wpa_supplicant_set_state(wpa_s,
1061 						 wpa_s->scan_prev_wpa_state);
1062 		/* Restore scan_req since we will try to scan again */
1063 		wpa_s->scan_req = wpa_s->last_scan_req;
1064 		wpa_supplicant_req_scan(wpa_s, 1, 0);
1065 	} else {
1066 		wpa_s->scan_for_connection = 0;
1067 #ifdef CONFIG_INTERWORKING
1068 		wpa_s->interworking_fast_assoc_tried = 0;
1069 #endif /* CONFIG_INTERWORKING */
1070 	}
1071 }
1072 
1073 
wpa_supplicant_update_scan_int(struct wpa_supplicant * wpa_s,int sec)1074 void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
1075 {
1076 	struct os_reltime remaining, new_int;
1077 	int cancelled;
1078 
1079 	cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
1080 					     &remaining);
1081 
1082 	new_int.sec = sec;
1083 	new_int.usec = 0;
1084 	if (cancelled && os_reltime_before(&remaining, &new_int)) {
1085 		new_int.sec = remaining.sec;
1086 		new_int.usec = remaining.usec;
1087 	}
1088 
1089 	if (cancelled) {
1090 		eloop_register_timeout(new_int.sec, new_int.usec,
1091 				       wpa_supplicant_scan, wpa_s, NULL);
1092 	}
1093 	wpa_s->scan_interval = sec;
1094 }
1095 
1096 
1097 /**
1098  * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
1099  * @wpa_s: Pointer to wpa_supplicant data
1100  * @sec: Number of seconds after which to scan
1101  * @usec: Number of microseconds after which to scan
1102  *
1103  * This function is used to schedule a scan for neighboring access points after
1104  * the specified time.
1105  */
wpa_supplicant_req_scan(struct wpa_supplicant * wpa_s,int sec,int usec)1106 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
1107 {
1108 	int res;
1109 
1110 	if (wpa_s->p2p_mgmt) {
1111 		wpa_dbg(wpa_s, MSG_DEBUG,
1112 			"Ignore scan request (%d.%06d sec) on p2p_mgmt interface",
1113 			sec, usec);
1114 		return;
1115 	}
1116 
1117 	res = eloop_deplete_timeout(sec, usec, wpa_supplicant_scan, wpa_s,
1118 				    NULL);
1119 	if (res == 1) {
1120 		wpa_dbg(wpa_s, MSG_DEBUG, "Rescheduling scan request: %d.%06d sec",
1121 			sec, usec);
1122 	} else if (res == 0) {
1123 		wpa_dbg(wpa_s, MSG_DEBUG, "Ignore new scan request for %d.%06d sec since an earlier request is scheduled to trigger sooner",
1124 			sec, usec);
1125 	} else {
1126 		wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d.%06d sec",
1127 			sec, usec);
1128 		eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
1129 	}
1130 }
1131 
1132 
1133 /**
1134  * wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
1135  * @wpa_s: Pointer to wpa_supplicant data
1136  * @sec: Number of seconds after which to scan
1137  * @usec: Number of microseconds after which to scan
1138  * Returns: 0 on success or -1 otherwise
1139  *
1140  * This function is used to schedule periodic scans for neighboring
1141  * access points after the specified time.
1142  */
wpa_supplicant_delayed_sched_scan(struct wpa_supplicant * wpa_s,int sec,int usec)1143 int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
1144 				      int sec, int usec)
1145 {
1146 	if (!wpa_s->sched_scan_supported)
1147 		return -1;
1148 
1149 	eloop_register_timeout(sec, usec,
1150 			       wpa_supplicant_delayed_sched_scan_timeout,
1151 			       wpa_s, NULL);
1152 
1153 	return 0;
1154 }
1155 
1156 
1157 /**
1158  * wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
1159  * @wpa_s: Pointer to wpa_supplicant data
1160  * Returns: 0 is sched_scan was started or -1 otherwise
1161  *
1162  * This function is used to schedule periodic scans for neighboring
1163  * access points repeating the scan continuously.
1164  */
wpa_supplicant_req_sched_scan(struct wpa_supplicant * wpa_s)1165 int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
1166 {
1167 	struct wpa_driver_scan_params params;
1168 	struct wpa_driver_scan_params *scan_params;
1169 	enum wpa_states prev_state;
1170 	struct wpa_ssid *ssid = NULL;
1171 	struct wpabuf *extra_ie = NULL;
1172 	int ret;
1173 	unsigned int max_sched_scan_ssids;
1174 	int wildcard = 0;
1175 	int need_ssids;
1176 
1177 	if (!wpa_s->sched_scan_supported)
1178 		return -1;
1179 
1180 	if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
1181 		max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
1182 	else
1183 		max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
1184 	if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
1185 		return -1;
1186 
1187 	if (wpa_s->sched_scanning) {
1188 		wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
1189 		return 0;
1190 	}
1191 
1192 	need_ssids = 0;
1193 	for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
1194 		if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
1195 			/* Use wildcard SSID to find this network */
1196 			wildcard = 1;
1197 		} else if (!wpas_network_disabled(wpa_s, ssid) &&
1198 			   ssid->ssid_len)
1199 			need_ssids++;
1200 
1201 #ifdef CONFIG_WPS
1202 		if (!wpas_network_disabled(wpa_s, ssid) &&
1203 		    ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
1204 			/*
1205 			 * Normal scan is more reliable and faster for WPS
1206 			 * operations and since these are for short periods of
1207 			 * time, the benefit of trying to use sched_scan would
1208 			 * be limited.
1209 			 */
1210 			wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1211 				"sched_scan for WPS");
1212 			return -1;
1213 		}
1214 #endif /* CONFIG_WPS */
1215 	}
1216 	if (wildcard)
1217 		need_ssids++;
1218 
1219 	if (wpa_s->normal_scans < 3 &&
1220 	    (need_ssids <= wpa_s->max_scan_ssids ||
1221 	     wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
1222 		/*
1223 		 * When normal scan can speed up operations, use that for the
1224 		 * first operations before starting the sched_scan to allow
1225 		 * user space sleep more. We do this only if the normal scan
1226 		 * has functionality that is suitable for this or if the
1227 		 * sched_scan does not have better support for multiple SSIDs.
1228 		 */
1229 		wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
1230 			"sched_scan for initial scans (normal_scans=%d)",
1231 			wpa_s->normal_scans);
1232 		return -1;
1233 	}
1234 
1235 	os_memset(&params, 0, sizeof(params));
1236 
1237 	/* If we can't allocate space for the filters, we just don't filter */
1238 	params.filter_ssids = os_calloc(wpa_s->max_match_sets,
1239 					sizeof(struct wpa_driver_scan_filter));
1240 
1241 	prev_state = wpa_s->wpa_state;
1242 	if (wpa_s->wpa_state == WPA_DISCONNECTED ||
1243 	    wpa_s->wpa_state == WPA_INACTIVE)
1244 		wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
1245 
1246 	if (wpa_s->autoscan_params != NULL) {
1247 		scan_params = wpa_s->autoscan_params;
1248 		goto scan;
1249 	}
1250 
1251 	/* Find the starting point from which to continue scanning */
1252 	ssid = wpa_s->conf->ssid;
1253 	if (wpa_s->prev_sched_ssid) {
1254 		while (ssid) {
1255 			if (ssid == wpa_s->prev_sched_ssid) {
1256 				ssid = ssid->next;
1257 				break;
1258 			}
1259 			ssid = ssid->next;
1260 		}
1261 	}
1262 
1263 	if (!ssid || !wpa_s->prev_sched_ssid) {
1264 		wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
1265 		if (wpa_s->conf->sched_scan_interval)
1266 			wpa_s->sched_scan_interval =
1267 				wpa_s->conf->sched_scan_interval;
1268 		if (wpa_s->sched_scan_interval == 0)
1269 			wpa_s->sched_scan_interval = 10;
1270 		wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1271 		wpa_s->first_sched_scan = 1;
1272 		ssid = wpa_s->conf->ssid;
1273 		wpa_s->prev_sched_ssid = ssid;
1274 	}
1275 
1276 	if (wildcard) {
1277 		wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
1278 		params.num_ssids++;
1279 	}
1280 
1281 	while (ssid) {
1282 		if (wpas_network_disabled(wpa_s, ssid))
1283 			goto next;
1284 
1285 		if (params.num_filter_ssids < wpa_s->max_match_sets &&
1286 		    params.filter_ssids && ssid->ssid && ssid->ssid_len) {
1287 			wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
1288 				wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1289 			os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
1290 				  ssid->ssid, ssid->ssid_len);
1291 			params.filter_ssids[params.num_filter_ssids].ssid_len =
1292 				ssid->ssid_len;
1293 			params.num_filter_ssids++;
1294 		} else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
1295 		{
1296 			wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
1297 				"filter for sched_scan - drop filter");
1298 			os_free(params.filter_ssids);
1299 			params.filter_ssids = NULL;
1300 			params.num_filter_ssids = 0;
1301 		}
1302 
1303 		if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
1304 			if (params.num_ssids == max_sched_scan_ssids)
1305 				break; /* only room for broadcast SSID */
1306 			wpa_dbg(wpa_s, MSG_DEBUG,
1307 				"add to active scan ssid: %s",
1308 				wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
1309 			params.ssids[params.num_ssids].ssid =
1310 				ssid->ssid;
1311 			params.ssids[params.num_ssids].ssid_len =
1312 				ssid->ssid_len;
1313 			params.num_ssids++;
1314 			if (params.num_ssids >= max_sched_scan_ssids) {
1315 				wpa_s->prev_sched_ssid = ssid;
1316 				do {
1317 					ssid = ssid->next;
1318 				} while (ssid &&
1319 					 (wpas_network_disabled(wpa_s, ssid) ||
1320 					  !ssid->scan_ssid));
1321 				break;
1322 			}
1323 		}
1324 
1325 	next:
1326 		wpa_s->prev_sched_ssid = ssid;
1327 		ssid = ssid->next;
1328 	}
1329 
1330 	if (params.num_filter_ssids == 0) {
1331 		os_free(params.filter_ssids);
1332 		params.filter_ssids = NULL;
1333 	}
1334 
1335 	extra_ie = wpa_supplicant_extra_ies(wpa_s);
1336 	if (extra_ie) {
1337 		params.extra_ies = wpabuf_head(extra_ie);
1338 		params.extra_ies_len = wpabuf_len(extra_ie);
1339 	}
1340 
1341 	if (wpa_s->conf->filter_rssi)
1342 		params.filter_rssi = wpa_s->conf->filter_rssi;
1343 
1344 	/* See if user specified frequencies. If so, scan only those. */
1345 	if (wpa_s->conf->freq_list && !params.freqs) {
1346 		wpa_dbg(wpa_s, MSG_DEBUG,
1347 			"Optimize scan based on conf->freq_list");
1348 		int_array_concat(&params.freqs, wpa_s->conf->freq_list);
1349 	}
1350 
1351 	scan_params = &params;
1352 
1353 scan:
1354 	if (ssid || !wpa_s->first_sched_scan) {
1355 		wpa_dbg(wpa_s, MSG_DEBUG,
1356 			"Starting sched scan: interval %d timeout %d",
1357 			wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
1358 	} else {
1359 		wpa_dbg(wpa_s, MSG_DEBUG,
1360 			"Starting sched scan: interval %d (no timeout)",
1361 			wpa_s->sched_scan_interval);
1362 	}
1363 
1364 	wpa_setband_scan_freqs(wpa_s, scan_params);
1365 
1366 	if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_SCHED_SCAN) {
1367 		params.mac_addr_rand = 1;
1368 		if (wpa_s->mac_addr_sched_scan) {
1369 			params.mac_addr = wpa_s->mac_addr_sched_scan;
1370 			params.mac_addr_mask = wpa_s->mac_addr_sched_scan +
1371 				ETH_ALEN;
1372 		}
1373 	}
1374 
1375 	ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
1376 					      wpa_s->sched_scan_interval);
1377 	wpabuf_free(extra_ie);
1378 	os_free(params.filter_ssids);
1379 	if (ret) {
1380 		wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
1381 		if (prev_state != wpa_s->wpa_state)
1382 			wpa_supplicant_set_state(wpa_s, prev_state);
1383 		return ret;
1384 	}
1385 
1386 	/* If we have more SSIDs to scan, add a timeout so we scan them too */
1387 	if (ssid || !wpa_s->first_sched_scan) {
1388 		wpa_s->sched_scan_timed_out = 0;
1389 		eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
1390 				       wpa_supplicant_sched_scan_timeout,
1391 				       wpa_s, NULL);
1392 		wpa_s->first_sched_scan = 0;
1393 		wpa_s->sched_scan_timeout /= 2;
1394 		wpa_s->sched_scan_interval *= 2;
1395 		if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
1396 			wpa_s->sched_scan_interval = 10;
1397 			wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
1398 		}
1399 	}
1400 
1401 	/* If there is no more ssids, start next time from the beginning */
1402 	if (!ssid)
1403 		wpa_s->prev_sched_ssid = NULL;
1404 
1405 	return 0;
1406 }
1407 
1408 
1409 /**
1410  * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
1411  * @wpa_s: Pointer to wpa_supplicant data
1412  *
1413  * This function is used to cancel a scan request scheduled with
1414  * wpa_supplicant_req_scan().
1415  */
wpa_supplicant_cancel_scan(struct wpa_supplicant * wpa_s)1416 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
1417 {
1418 	wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
1419 	eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
1420 }
1421 
1422 
1423 /**
1424  * wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
1425  * @wpa_s: Pointer to wpa_supplicant data
1426  *
1427  * This function is used to stop a delayed scheduled scan.
1428  */
wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant * wpa_s)1429 void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
1430 {
1431 	if (!wpa_s->sched_scan_supported)
1432 		return;
1433 
1434 	wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
1435 	eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
1436 			     wpa_s, NULL);
1437 }
1438 
1439 
1440 /**
1441  * wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
1442  * @wpa_s: Pointer to wpa_supplicant data
1443  *
1444  * This function is used to stop a periodic scheduled scan.
1445  */
wpa_supplicant_cancel_sched_scan(struct wpa_supplicant * wpa_s)1446 void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
1447 {
1448 	if (!wpa_s->sched_scanning)
1449 		return;
1450 
1451 	wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
1452 	eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
1453 	wpa_supplicant_stop_sched_scan(wpa_s);
1454 }
1455 
1456 
1457 /**
1458  * wpa_supplicant_notify_scanning - Indicate possible scan state change
1459  * @wpa_s: Pointer to wpa_supplicant data
1460  * @scanning: Whether scanning is currently in progress
1461  *
1462  * This function is to generate scanning notifycations. It is called whenever
1463  * there may have been a change in scanning (scan started, completed, stopped).
1464  * wpas_notify_scanning() is called whenever the scanning state changed from the
1465  * previously notified state.
1466  */
wpa_supplicant_notify_scanning(struct wpa_supplicant * wpa_s,int scanning)1467 void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
1468 				    int scanning)
1469 {
1470 	if (wpa_s->scanning != scanning) {
1471 		wpa_s->scanning = scanning;
1472 		wpas_notify_scanning(wpa_s);
1473 	}
1474 }
1475 
1476 
wpa_scan_get_max_rate(const struct wpa_scan_res * res)1477 static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
1478 {
1479 	int rate = 0;
1480 	const u8 *ie;
1481 	int i;
1482 
1483 	ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
1484 	for (i = 0; ie && i < ie[1]; i++) {
1485 		if ((ie[i + 2] & 0x7f) > rate)
1486 			rate = ie[i + 2] & 0x7f;
1487 	}
1488 
1489 	ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
1490 	for (i = 0; ie && i < ie[1]; i++) {
1491 		if ((ie[i + 2] & 0x7f) > rate)
1492 			rate = ie[i + 2] & 0x7f;
1493 	}
1494 
1495 	return rate;
1496 }
1497 
1498 
1499 /**
1500  * wpa_scan_get_ie - Fetch a specified information element from a scan result
1501  * @res: Scan result entry
1502  * @ie: Information element identitifier (WLAN_EID_*)
1503  * Returns: Pointer to the information element (id field) or %NULL if not found
1504  *
1505  * This function returns the first matching information element in the scan
1506  * result.
1507  */
wpa_scan_get_ie(const struct wpa_scan_res * res,u8 ie)1508 const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
1509 {
1510 	const u8 *end, *pos;
1511 
1512 	pos = (const u8 *) (res + 1);
1513 	end = pos + res->ie_len;
1514 
1515 	while (pos + 1 < end) {
1516 		if (pos + 2 + pos[1] > end)
1517 			break;
1518 		if (pos[0] == ie)
1519 			return pos;
1520 		pos += 2 + pos[1];
1521 	}
1522 
1523 	return NULL;
1524 }
1525 
1526 
1527 /**
1528  * wpa_scan_get_vendor_ie - Fetch vendor information element from a scan result
1529  * @res: Scan result entry
1530  * @vendor_type: Vendor type (four octets starting the IE payload)
1531  * Returns: Pointer to the information element (id field) or %NULL if not found
1532  *
1533  * This function returns the first matching information element in the scan
1534  * result.
1535  */
wpa_scan_get_vendor_ie(const struct wpa_scan_res * res,u32 vendor_type)1536 const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
1537 				  u32 vendor_type)
1538 {
1539 	const u8 *end, *pos;
1540 
1541 	pos = (const u8 *) (res + 1);
1542 	end = pos + res->ie_len;
1543 
1544 	while (pos + 1 < end) {
1545 		if (pos + 2 + pos[1] > end)
1546 			break;
1547 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1548 		    vendor_type == WPA_GET_BE32(&pos[2]))
1549 			return pos;
1550 		pos += 2 + pos[1];
1551 	}
1552 
1553 	return NULL;
1554 }
1555 
1556 
1557 /**
1558  * wpa_scan_get_vendor_ie_beacon - Fetch vendor information from a scan result
1559  * @res: Scan result entry
1560  * @vendor_type: Vendor type (four octets starting the IE payload)
1561  * Returns: Pointer to the information element (id field) or %NULL if not found
1562  *
1563  * This function returns the first matching information element in the scan
1564  * result.
1565  *
1566  * This function is like wpa_scan_get_vendor_ie(), but uses IE buffer only
1567  * from Beacon frames instead of either Beacon or Probe Response frames.
1568  */
wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res * res,u32 vendor_type)1569 const u8 * wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res *res,
1570 					 u32 vendor_type)
1571 {
1572 	const u8 *end, *pos;
1573 
1574 	if (res->beacon_ie_len == 0)
1575 		return NULL;
1576 
1577 	pos = (const u8 *) (res + 1);
1578 	pos += res->ie_len;
1579 	end = pos + res->beacon_ie_len;
1580 
1581 	while (pos + 1 < end) {
1582 		if (pos + 2 + pos[1] > end)
1583 			break;
1584 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1585 		    vendor_type == WPA_GET_BE32(&pos[2]))
1586 			return pos;
1587 		pos += 2 + pos[1];
1588 	}
1589 
1590 	return NULL;
1591 }
1592 
1593 
1594 /**
1595  * wpa_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
1596  * @res: Scan result entry
1597  * @vendor_type: Vendor type (four octets starting the IE payload)
1598  * Returns: Pointer to the information element payload or %NULL if not found
1599  *
1600  * This function returns concatenated payload of possibly fragmented vendor
1601  * specific information elements in the scan result. The caller is responsible
1602  * for freeing the returned buffer.
1603  */
wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res * res,u32 vendor_type)1604 struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
1605 					     u32 vendor_type)
1606 {
1607 	struct wpabuf *buf;
1608 	const u8 *end, *pos;
1609 
1610 	buf = wpabuf_alloc(res->ie_len);
1611 	if (buf == NULL)
1612 		return NULL;
1613 
1614 	pos = (const u8 *) (res + 1);
1615 	end = pos + res->ie_len;
1616 
1617 	while (pos + 1 < end) {
1618 		if (pos + 2 + pos[1] > end)
1619 			break;
1620 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1621 		    vendor_type == WPA_GET_BE32(&pos[2]))
1622 			wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1623 		pos += 2 + pos[1];
1624 	}
1625 
1626 	if (wpabuf_len(buf) == 0) {
1627 		wpabuf_free(buf);
1628 		buf = NULL;
1629 	}
1630 
1631 	return buf;
1632 }
1633 
1634 
1635 /*
1636  * Channels with a great SNR can operate at full rate. What is a great SNR?
1637  * This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
1638  * rule of thumb is that any SNR above 20 is good." This one
1639  * http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
1640  * recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
1641  * conservative value.
1642  */
1643 #define GREAT_SNR 30
1644 
1645 #define IS_5GHZ(n) (n > 4000)
1646 
1647 /* Compare function for sorting scan results. Return >0 if @b is considered
1648  * better. */
wpa_scan_result_compar(const void * a,const void * b)1649 static int wpa_scan_result_compar(const void *a, const void *b)
1650 {
1651 #define MIN(a,b) a < b ? a : b
1652 	struct wpa_scan_res **_wa = (void *) a;
1653 	struct wpa_scan_res **_wb = (void *) b;
1654 	struct wpa_scan_res *wa = *_wa;
1655 	struct wpa_scan_res *wb = *_wb;
1656 	int wpa_a, wpa_b;
1657 	int snr_a, snr_b, snr_a_full, snr_b_full;
1658 
1659 	/* WPA/WPA2 support preferred */
1660 	wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
1661 		wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
1662 	wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
1663 		wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
1664 
1665 	if (wpa_b && !wpa_a)
1666 		return 1;
1667 	if (!wpa_b && wpa_a)
1668 		return -1;
1669 
1670 	/* privacy support preferred */
1671 	if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
1672 	    (wb->caps & IEEE80211_CAP_PRIVACY))
1673 		return 1;
1674 	if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
1675 	    (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
1676 		return -1;
1677 
1678 	if (wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) {
1679 		snr_a_full = wa->snr;
1680 		snr_a = MIN(wa->snr, GREAT_SNR);
1681 		snr_b_full = wb->snr;
1682 		snr_b = MIN(wa->snr, GREAT_SNR);
1683 	} else {
1684 		/* Level is not in dBm, so we can't calculate
1685 		 * SNR. Just use raw level (units unknown). */
1686 		snr_a = snr_a_full = wa->level;
1687 		snr_b = snr_b_full = wb->level;
1688 	}
1689 
1690 	/* if SNR is close, decide by max rate or frequency band */
1691 	if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
1692 	    (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
1693 		if (wa->est_throughput != wb->est_throughput)
1694 			return wb->est_throughput - wa->est_throughput;
1695 		if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
1696 			return IS_5GHZ(wa->freq) ? -1 : 1;
1697 	}
1698 
1699 	/* all things being equal, use SNR; if SNRs are
1700 	 * identical, use quality values since some drivers may only report
1701 	 * that value and leave the signal level zero */
1702 	if (snr_b_full == snr_a_full)
1703 		return wb->qual - wa->qual;
1704 	return snr_b_full - snr_a_full;
1705 #undef MIN
1706 }
1707 
1708 
1709 #ifdef CONFIG_WPS
1710 /* Compare function for sorting scan results when searching a WPS AP for
1711  * provisioning. Return >0 if @b is considered better. */
wpa_scan_result_wps_compar(const void * a,const void * b)1712 static int wpa_scan_result_wps_compar(const void *a, const void *b)
1713 {
1714 	struct wpa_scan_res **_wa = (void *) a;
1715 	struct wpa_scan_res **_wb = (void *) b;
1716 	struct wpa_scan_res *wa = *_wa;
1717 	struct wpa_scan_res *wb = *_wb;
1718 	int uses_wps_a, uses_wps_b;
1719 	struct wpabuf *wps_a, *wps_b;
1720 	int res;
1721 
1722 	/* Optimization - check WPS IE existence before allocated memory and
1723 	 * doing full reassembly. */
1724 	uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
1725 	uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
1726 	if (uses_wps_a && !uses_wps_b)
1727 		return -1;
1728 	if (!uses_wps_a && uses_wps_b)
1729 		return 1;
1730 
1731 	if (uses_wps_a && uses_wps_b) {
1732 		wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
1733 		wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
1734 		res = wps_ap_priority_compar(wps_a, wps_b);
1735 		wpabuf_free(wps_a);
1736 		wpabuf_free(wps_b);
1737 		if (res)
1738 			return res;
1739 	}
1740 
1741 	/*
1742 	 * Do not use current AP security policy as a sorting criteria during
1743 	 * WPS provisioning step since the AP may get reconfigured at the
1744 	 * completion of provisioning.
1745 	 */
1746 
1747 	/* all things being equal, use signal level; if signal levels are
1748 	 * identical, use quality values since some drivers may only report
1749 	 * that value and leave the signal level zero */
1750 	if (wb->level == wa->level)
1751 		return wb->qual - wa->qual;
1752 	return wb->level - wa->level;
1753 }
1754 #endif /* CONFIG_WPS */
1755 
1756 
dump_scan_res(struct wpa_scan_results * scan_res)1757 static void dump_scan_res(struct wpa_scan_results *scan_res)
1758 {
1759 #ifndef CONFIG_NO_STDOUT_DEBUG
1760 	size_t i;
1761 
1762 	if (scan_res->res == NULL || scan_res->num == 0)
1763 		return;
1764 
1765 	wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
1766 
1767 	for (i = 0; i < scan_res->num; i++) {
1768 		struct wpa_scan_res *r = scan_res->res[i];
1769 		u8 *pos;
1770 		if (r->flags & WPA_SCAN_LEVEL_DBM) {
1771 			int noise_valid = !(r->flags & WPA_SCAN_NOISE_INVALID);
1772 
1773 			wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1774 				   "noise=%d%s level=%d snr=%d%s flags=0x%x age=%u est=%u",
1775 				   MAC2STR(r->bssid), r->freq, r->qual,
1776 				   r->noise, noise_valid ? "" : "~", r->level,
1777 				   r->snr, r->snr >= GREAT_SNR ? "*" : "",
1778 				   r->flags,
1779 				   r->age, r->est_throughput);
1780 		} else {
1781 			wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
1782 				   "noise=%d level=%d flags=0x%x age=%u est=%u",
1783 				   MAC2STR(r->bssid), r->freq, r->qual,
1784 				   r->noise, r->level, r->flags, r->age,
1785 				   r->est_throughput);
1786 		}
1787 		pos = (u8 *) (r + 1);
1788 		if (r->ie_len)
1789 			wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
1790 		pos += r->ie_len;
1791 		if (r->beacon_ie_len)
1792 			wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
1793 				    pos, r->beacon_ie_len);
1794 	}
1795 #endif /* CONFIG_NO_STDOUT_DEBUG */
1796 }
1797 
1798 
1799 /**
1800  * wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
1801  * @wpa_s: Pointer to wpa_supplicant data
1802  * @bssid: BSSID to check
1803  * Returns: 0 if the BSSID is filtered or 1 if not
1804  *
1805  * This function is used to filter out specific BSSIDs from scan reslts mainly
1806  * for testing purposes (SET bssid_filter ctrl_iface command).
1807  */
wpa_supplicant_filter_bssid_match(struct wpa_supplicant * wpa_s,const u8 * bssid)1808 int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
1809 				      const u8 *bssid)
1810 {
1811 	size_t i;
1812 
1813 	if (wpa_s->bssid_filter == NULL)
1814 		return 1;
1815 
1816 	for (i = 0; i < wpa_s->bssid_filter_count; i++) {
1817 		if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
1818 			      ETH_ALEN) == 0)
1819 			return 1;
1820 	}
1821 
1822 	return 0;
1823 }
1824 
1825 
filter_scan_res(struct wpa_supplicant * wpa_s,struct wpa_scan_results * res)1826 static void filter_scan_res(struct wpa_supplicant *wpa_s,
1827 			    struct wpa_scan_results *res)
1828 {
1829 	size_t i, j;
1830 
1831 	if (wpa_s->bssid_filter == NULL)
1832 		return;
1833 
1834 	for (i = 0, j = 0; i < res->num; i++) {
1835 		if (wpa_supplicant_filter_bssid_match(wpa_s,
1836 						      res->res[i]->bssid)) {
1837 			res->res[j++] = res->res[i];
1838 		} else {
1839 			os_free(res->res[i]);
1840 			res->res[i] = NULL;
1841 		}
1842 	}
1843 
1844 	if (res->num != j) {
1845 		wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
1846 			   (int) (res->num - j));
1847 		res->num = j;
1848 	}
1849 }
1850 
1851 
1852 /*
1853  * Noise floor values to use when we have signal strength
1854  * measurements, but no noise floor measurments. These values were
1855  * measured in an office environment with many APs.
1856  */
1857 #define DEFAULT_NOISE_FLOOR_2GHZ (-89)
1858 #define DEFAULT_NOISE_FLOOR_5GHZ (-92)
1859 
scan_snr(struct wpa_scan_res * res)1860 static void scan_snr(struct wpa_scan_res *res)
1861 {
1862 	if (res->flags & WPA_SCAN_NOISE_INVALID) {
1863 		res->noise = IS_5GHZ(res->freq) ?
1864 			DEFAULT_NOISE_FLOOR_5GHZ :
1865 			DEFAULT_NOISE_FLOOR_2GHZ;
1866 	}
1867 
1868 	if (res->flags & WPA_SCAN_LEVEL_DBM) {
1869 		res->snr = res->level - res->noise;
1870 	} else {
1871 		/* Level is not in dBm, so we can't calculate
1872 		 * SNR. Just use raw level (units unknown). */
1873 		res->snr = res->level;
1874 	}
1875 }
1876 
1877 
max_ht20_rate(int snr)1878 static unsigned int max_ht20_rate(int snr)
1879 {
1880 	if (snr < 6)
1881 		return 6500; /* HT20 MCS0 */
1882 	if (snr < 8)
1883 		return 13000; /* HT20 MCS1 */
1884 	if (snr < 13)
1885 		return 19500; /* HT20 MCS2 */
1886 	if (snr < 17)
1887 		return 26000; /* HT20 MCS3 */
1888 	if (snr < 20)
1889 		return 39000; /* HT20 MCS4 */
1890 	if (snr < 23)
1891 		return 52000; /* HT20 MCS5 */
1892 	if (snr < 24)
1893 		return 58500; /* HT20 MCS6 */
1894 	return 65000; /* HT20 MCS7 */
1895 }
1896 
1897 
max_ht40_rate(int snr)1898 static unsigned int max_ht40_rate(int snr)
1899 {
1900 	if (snr < 3)
1901 		return 13500; /* HT40 MCS0 */
1902 	if (snr < 6)
1903 		return 27000; /* HT40 MCS1 */
1904 	if (snr < 10)
1905 		return 40500; /* HT40 MCS2 */
1906 	if (snr < 15)
1907 		return 54000; /* HT40 MCS3 */
1908 	if (snr < 17)
1909 		return 81000; /* HT40 MCS4 */
1910 	if (snr < 22)
1911 		return 108000; /* HT40 MCS5 */
1912 	if (snr < 24)
1913 		return 121500; /* HT40 MCS6 */
1914 	return 135000; /* HT40 MCS7 */
1915 }
1916 
1917 
max_vht80_rate(int snr)1918 static unsigned int max_vht80_rate(int snr)
1919 {
1920 	if (snr < 1)
1921 		return 0;
1922 	if (snr < 2)
1923 		return 29300; /* VHT80 MCS0 */
1924 	if (snr < 5)
1925 		return 58500; /* VHT80 MCS1 */
1926 	if (snr < 9)
1927 		return 87800; /* VHT80 MCS2 */
1928 	if (snr < 11)
1929 		return 117000; /* VHT80 MCS3 */
1930 	if (snr < 15)
1931 		return 175500; /* VHT80 MCS4 */
1932 	if (snr < 16)
1933 		return 234000; /* VHT80 MCS5 */
1934 	if (snr < 18)
1935 		return 263300; /* VHT80 MCS6 */
1936 	if (snr < 20)
1937 		return 292500; /* VHT80 MCS7 */
1938 	if (snr < 22)
1939 		return 351000; /* VHT80 MCS8 */
1940 	return 390000; /* VHT80 MCS9 */
1941 }
1942 
1943 
scan_est_throughput(struct wpa_supplicant * wpa_s,struct wpa_scan_res * res)1944 static void scan_est_throughput(struct wpa_supplicant *wpa_s,
1945 				struct wpa_scan_res *res)
1946 {
1947 	enum local_hw_capab capab = wpa_s->hw_capab;
1948 	int rate; /* max legacy rate in 500 kb/s units */
1949 	const u8 *ie;
1950 	unsigned int est, tmp;
1951 	int snr = res->snr;
1952 
1953 	if (res->est_throughput)
1954 		return;
1955 
1956 	/* Get maximum legacy rate */
1957 	rate = wpa_scan_get_max_rate(res);
1958 
1959 	/* Limit based on estimated SNR */
1960 	if (rate > 1 * 2 && snr < 1)
1961 		rate = 1 * 2;
1962 	else if (rate > 2 * 2 && snr < 4)
1963 		rate = 2 * 2;
1964 	else if (rate > 6 * 2 && snr < 5)
1965 		rate = 6 * 2;
1966 	else if (rate > 9 * 2 && snr < 6)
1967 		rate = 9 * 2;
1968 	else if (rate > 12 * 2 && snr < 7)
1969 		rate = 12 * 2;
1970 	else if (rate > 18 * 2 && snr < 10)
1971 		rate = 18 * 2;
1972 	else if (rate > 24 * 2 && snr < 11)
1973 		rate = 24 * 2;
1974 	else if (rate > 36 * 2 && snr < 15)
1975 		rate = 36 * 2;
1976 	else if (rate > 48 * 2 && snr < 19)
1977 		rate = 48 * 2;
1978 	else if (rate > 54 * 2 && snr < 21)
1979 		rate = 54 * 2;
1980 	est = rate * 500;
1981 
1982 	if (capab == CAPAB_HT || capab == CAPAB_HT40 || capab == CAPAB_VHT) {
1983 		ie = wpa_scan_get_ie(res, WLAN_EID_HT_CAP);
1984 		if (ie) {
1985 			tmp = max_ht20_rate(snr);
1986 			if (tmp > est)
1987 				est = tmp;
1988 		}
1989 	}
1990 
1991 	if (capab == CAPAB_HT40 || capab == CAPAB_VHT) {
1992 		ie = wpa_scan_get_ie(res, WLAN_EID_HT_OPERATION);
1993 		if (ie && ie[1] >= 2 &&
1994 		    (ie[3] & HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK)) {
1995 			tmp = max_ht40_rate(snr);
1996 			if (tmp > est)
1997 				est = tmp;
1998 		}
1999 	}
2000 
2001 	if (capab == CAPAB_VHT) {
2002 		/* Use +1 to assume VHT is always faster than HT */
2003 		ie = wpa_scan_get_ie(res, WLAN_EID_VHT_CAP);
2004 		if (ie) {
2005 			tmp = max_ht20_rate(snr) + 1;
2006 			if (tmp > est)
2007 				est = tmp;
2008 
2009 			ie = wpa_scan_get_ie(res, WLAN_EID_HT_OPERATION);
2010 			if (ie && ie[1] >= 2 &&
2011 			    (ie[3] &
2012 			     HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK)) {
2013 				tmp = max_ht40_rate(snr) + 1;
2014 				if (tmp > est)
2015 					est = tmp;
2016 			}
2017 
2018 			ie = wpa_scan_get_ie(res, WLAN_EID_VHT_OPERATION);
2019 			if (ie && ie[1] >= 1 &&
2020 			    (ie[2] & VHT_OPMODE_CHANNEL_WIDTH_MASK)) {
2021 				tmp = max_vht80_rate(snr) + 1;
2022 				if (tmp > est)
2023 					est = tmp;
2024 			}
2025 		}
2026 	}
2027 
2028 	/* TODO: channel utilization and AP load (e.g., from AP Beacon) */
2029 
2030 	res->est_throughput = est;
2031 }
2032 
2033 
2034 /**
2035  * wpa_supplicant_get_scan_results - Get scan results
2036  * @wpa_s: Pointer to wpa_supplicant data
2037  * @info: Information about what was scanned or %NULL if not available
2038  * @new_scan: Whether a new scan was performed
2039  * Returns: Scan results, %NULL on failure
2040  *
2041  * This function request the current scan results from the driver and updates
2042  * the local BSS list wpa_s->bss. The caller is responsible for freeing the
2043  * results with wpa_scan_results_free().
2044  */
2045 struct wpa_scan_results *
wpa_supplicant_get_scan_results(struct wpa_supplicant * wpa_s,struct scan_info * info,int new_scan)2046 wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
2047 				struct scan_info *info, int new_scan)
2048 {
2049 	struct wpa_scan_results *scan_res;
2050 	size_t i;
2051 	int (*compar)(const void *, const void *) = wpa_scan_result_compar;
2052 
2053 	scan_res = wpa_drv_get_scan_results2(wpa_s);
2054 	if (scan_res == NULL) {
2055 		wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
2056 		return NULL;
2057 	}
2058 	if (scan_res->fetch_time.sec == 0) {
2059 		/*
2060 		 * Make sure we have a valid timestamp if the driver wrapper
2061 		 * does not set this.
2062 		 */
2063 		os_get_reltime(&scan_res->fetch_time);
2064 	}
2065 	filter_scan_res(wpa_s, scan_res);
2066 
2067 	for (i = 0; i < scan_res->num; i++) {
2068 		struct wpa_scan_res *scan_res_item = scan_res->res[i];
2069 
2070 		scan_snr(scan_res_item);
2071 		scan_est_throughput(wpa_s, scan_res_item);
2072 	}
2073 
2074 #ifdef CONFIG_WPS
2075 	if (wpas_wps_searching(wpa_s)) {
2076 		wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
2077 			"provisioning rules");
2078 		compar = wpa_scan_result_wps_compar;
2079 	}
2080 #endif /* CONFIG_WPS */
2081 
2082 	qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
2083 	      compar);
2084 	dump_scan_res(scan_res);
2085 
2086 	wpa_bss_update_start(wpa_s);
2087 	for (i = 0; i < scan_res->num; i++)
2088 		wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
2089 					&scan_res->fetch_time);
2090 	wpa_bss_update_end(wpa_s, info, new_scan);
2091 
2092 	return scan_res;
2093 }
2094 
2095 
2096 /**
2097  * wpa_supplicant_update_scan_results - Update scan results from the driver
2098  * @wpa_s: Pointer to wpa_supplicant data
2099  * Returns: 0 on success, -1 on failure
2100  *
2101  * This function updates the BSS table within wpa_supplicant based on the
2102  * currently available scan results from the driver without requesting a new
2103  * scan. This is used in cases where the driver indicates an association
2104  * (including roaming within ESS) and wpa_supplicant does not yet have the
2105  * needed information to complete the connection (e.g., to perform validation
2106  * steps in 4-way handshake).
2107  */
wpa_supplicant_update_scan_results(struct wpa_supplicant * wpa_s)2108 int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
2109 {
2110 	struct wpa_scan_results *scan_res;
2111 	scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
2112 	if (scan_res == NULL)
2113 		return -1;
2114 	wpa_scan_results_free(scan_res);
2115 
2116 	return 0;
2117 }
2118 
2119 
2120 /**
2121  * scan_only_handler - Reports scan results
2122  */
scan_only_handler(struct wpa_supplicant * wpa_s,struct wpa_scan_results * scan_res)2123 void scan_only_handler(struct wpa_supplicant *wpa_s,
2124 		       struct wpa_scan_results *scan_res)
2125 {
2126 	wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
2127 	if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
2128 	    wpa_s->manual_scan_use_id && wpa_s->own_scan_running) {
2129 		wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS "id=%u",
2130 			     wpa_s->manual_scan_id);
2131 		wpa_s->manual_scan_use_id = 0;
2132 	} else {
2133 		wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
2134 	}
2135 	wpas_notify_scan_results(wpa_s);
2136 	wpas_notify_scan_done(wpa_s, 1);
2137 	if (wpa_s->scan_work) {
2138 		struct wpa_radio_work *work = wpa_s->scan_work;
2139 		wpa_s->scan_work = NULL;
2140 		radio_work_done(work);
2141 	}
2142 }
2143 
2144 
wpas_scan_scheduled(struct wpa_supplicant * wpa_s)2145 int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
2146 {
2147 	return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
2148 }
2149 
2150 
2151 struct wpa_driver_scan_params *
wpa_scan_clone_params(const struct wpa_driver_scan_params * src)2152 wpa_scan_clone_params(const struct wpa_driver_scan_params *src)
2153 {
2154 	struct wpa_driver_scan_params *params;
2155 	size_t i;
2156 	u8 *n;
2157 
2158 	params = os_zalloc(sizeof(*params));
2159 	if (params == NULL)
2160 		return NULL;
2161 
2162 	for (i = 0; i < src->num_ssids; i++) {
2163 		if (src->ssids[i].ssid) {
2164 			n = os_malloc(src->ssids[i].ssid_len);
2165 			if (n == NULL)
2166 				goto failed;
2167 			os_memcpy(n, src->ssids[i].ssid,
2168 				  src->ssids[i].ssid_len);
2169 			params->ssids[i].ssid = n;
2170 			params->ssids[i].ssid_len = src->ssids[i].ssid_len;
2171 		}
2172 	}
2173 	params->num_ssids = src->num_ssids;
2174 
2175 	if (src->extra_ies) {
2176 		n = os_malloc(src->extra_ies_len);
2177 		if (n == NULL)
2178 			goto failed;
2179 		os_memcpy(n, src->extra_ies, src->extra_ies_len);
2180 		params->extra_ies = n;
2181 		params->extra_ies_len = src->extra_ies_len;
2182 	}
2183 
2184 	if (src->freqs) {
2185 		int len = int_array_len(src->freqs);
2186 		params->freqs = os_malloc((len + 1) * sizeof(int));
2187 		if (params->freqs == NULL)
2188 			goto failed;
2189 		os_memcpy(params->freqs, src->freqs, (len + 1) * sizeof(int));
2190 	}
2191 
2192 	if (src->filter_ssids) {
2193 		params->filter_ssids = os_malloc(sizeof(*params->filter_ssids) *
2194 						 src->num_filter_ssids);
2195 		if (params->filter_ssids == NULL)
2196 			goto failed;
2197 		os_memcpy(params->filter_ssids, src->filter_ssids,
2198 			  sizeof(*params->filter_ssids) *
2199 			  src->num_filter_ssids);
2200 		params->num_filter_ssids = src->num_filter_ssids;
2201 	}
2202 
2203 	params->filter_rssi = src->filter_rssi;
2204 	params->p2p_probe = src->p2p_probe;
2205 	params->only_new_results = src->only_new_results;
2206 	params->low_priority = src->low_priority;
2207 
2208 	if (src->mac_addr_rand) {
2209 		params->mac_addr_rand = src->mac_addr_rand;
2210 
2211 		if (src->mac_addr && src->mac_addr_mask) {
2212 			u8 *mac_addr;
2213 
2214 			mac_addr = os_malloc(2 * ETH_ALEN);
2215 			if (!mac_addr)
2216 				goto failed;
2217 
2218 			os_memcpy(mac_addr, src->mac_addr, ETH_ALEN);
2219 			os_memcpy(mac_addr + ETH_ALEN, src->mac_addr_mask,
2220 				  ETH_ALEN);
2221 			params->mac_addr = mac_addr;
2222 			params->mac_addr_mask = mac_addr + ETH_ALEN;
2223 		}
2224 	}
2225 	return params;
2226 
2227 failed:
2228 	wpa_scan_free_params(params);
2229 	return NULL;
2230 }
2231 
2232 
wpa_scan_free_params(struct wpa_driver_scan_params * params)2233 void wpa_scan_free_params(struct wpa_driver_scan_params *params)
2234 {
2235 	size_t i;
2236 
2237 	if (params == NULL)
2238 		return;
2239 
2240 	for (i = 0; i < params->num_ssids; i++)
2241 		os_free((u8 *) params->ssids[i].ssid);
2242 	os_free((u8 *) params->extra_ies);
2243 	os_free(params->freqs);
2244 	os_free(params->filter_ssids);
2245 
2246 	/*
2247 	 * Note: params->mac_addr_mask points to same memory allocation and
2248 	 * must not be freed separately.
2249 	 */
2250 	os_free((u8 *) params->mac_addr);
2251 
2252 	os_free(params);
2253 }
2254 
2255 
wpas_start_pno(struct wpa_supplicant * wpa_s)2256 int wpas_start_pno(struct wpa_supplicant *wpa_s)
2257 {
2258 	int ret, interval, prio;
2259 	size_t i, num_ssid, num_match_ssid;
2260 	struct wpa_ssid *ssid;
2261 	struct wpa_driver_scan_params params;
2262 
2263 	if (!wpa_s->sched_scan_supported)
2264 		return -1;
2265 
2266 	if (wpa_s->pno || wpa_s->pno_sched_pending)
2267 		return 0;
2268 
2269 	if ((wpa_s->wpa_state > WPA_SCANNING) &&
2270 	    (wpa_s->wpa_state <= WPA_COMPLETED)) {
2271 		wpa_printf(MSG_ERROR, "PNO: In assoc process");
2272 		return -EAGAIN;
2273 	}
2274 
2275 	if (wpa_s->wpa_state == WPA_SCANNING) {
2276 		wpa_supplicant_cancel_scan(wpa_s);
2277 		if (wpa_s->sched_scanning) {
2278 			wpa_printf(MSG_DEBUG, "Schedule PNO on completion of "
2279 				   "ongoing sched scan");
2280 			wpa_supplicant_cancel_sched_scan(wpa_s);
2281 			wpa_s->pno_sched_pending = 1;
2282 			return 0;
2283 		}
2284 	}
2285 
2286 	os_memset(&params, 0, sizeof(params));
2287 
2288 	num_ssid = num_match_ssid = 0;
2289 	ssid = wpa_s->conf->ssid;
2290 	while (ssid) {
2291 		if (!wpas_network_disabled(wpa_s, ssid)) {
2292 			num_match_ssid++;
2293 			if (ssid->scan_ssid)
2294 				num_ssid++;
2295 		}
2296 		ssid = ssid->next;
2297 	}
2298 
2299 	if (num_match_ssid == 0) {
2300 		wpa_printf(MSG_DEBUG, "PNO: No configured SSIDs");
2301 		return -1;
2302 	}
2303 
2304 	if (num_match_ssid > num_ssid) {
2305 		params.num_ssids++; /* wildcard */
2306 		num_ssid++;
2307 	}
2308 
2309 	if (num_ssid > WPAS_MAX_SCAN_SSIDS) {
2310 		wpa_printf(MSG_DEBUG, "PNO: Use only the first %u SSIDs from "
2311 			   "%u", WPAS_MAX_SCAN_SSIDS, (unsigned int) num_ssid);
2312 		num_ssid = WPAS_MAX_SCAN_SSIDS;
2313 	}
2314 
2315 	if (num_match_ssid > wpa_s->max_match_sets) {
2316 		num_match_ssid = wpa_s->max_match_sets;
2317 		wpa_dbg(wpa_s, MSG_DEBUG, "PNO: Too many SSIDs to match");
2318 	}
2319 	params.filter_ssids = os_calloc(num_match_ssid,
2320 					sizeof(struct wpa_driver_scan_filter));
2321 	if (params.filter_ssids == NULL)
2322 		return -1;
2323 
2324 	i = 0;
2325 	prio = 0;
2326 	ssid = wpa_s->conf->pssid[prio];
2327 	while (ssid) {
2328 		if (!wpas_network_disabled(wpa_s, ssid)) {
2329 			if (ssid->scan_ssid && params.num_ssids < num_ssid) {
2330 				params.ssids[params.num_ssids].ssid =
2331 					ssid->ssid;
2332 				params.ssids[params.num_ssids].ssid_len =
2333 					 ssid->ssid_len;
2334 				params.num_ssids++;
2335 			}
2336 			os_memcpy(params.filter_ssids[i].ssid, ssid->ssid,
2337 				  ssid->ssid_len);
2338 			params.filter_ssids[i].ssid_len = ssid->ssid_len;
2339 			params.num_filter_ssids++;
2340 			i++;
2341 			if (i == num_match_ssid)
2342 				break;
2343 		}
2344 		if (ssid->pnext)
2345 			ssid = ssid->pnext;
2346 		else if (prio + 1 == wpa_s->conf->num_prio)
2347 			break;
2348 		else
2349 			ssid = wpa_s->conf->pssid[++prio];
2350 	}
2351 
2352 	if (wpa_s->conf->filter_rssi)
2353 		params.filter_rssi = wpa_s->conf->filter_rssi;
2354 
2355 	interval = wpa_s->conf->sched_scan_interval ?
2356 		wpa_s->conf->sched_scan_interval : 10;
2357 
2358 	if (params.freqs == NULL && wpa_s->manual_sched_scan_freqs) {
2359 		wpa_dbg(wpa_s, MSG_DEBUG, "Limit sched scan to specified channels");
2360 		params.freqs = wpa_s->manual_sched_scan_freqs;
2361 	}
2362 
2363 	if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_PNO) {
2364 		params.mac_addr_rand = 1;
2365 		if (wpa_s->mac_addr_pno) {
2366 			params.mac_addr = wpa_s->mac_addr_pno;
2367 			params.mac_addr_mask = wpa_s->mac_addr_pno + ETH_ALEN;
2368 		}
2369 	}
2370 
2371 	ret = wpa_supplicant_start_sched_scan(wpa_s, &params, interval);
2372 	os_free(params.filter_ssids);
2373 	if (ret == 0)
2374 		wpa_s->pno = 1;
2375 	else
2376 		wpa_msg(wpa_s, MSG_ERROR, "Failed to schedule PNO");
2377 	return ret;
2378 }
2379 
2380 
wpas_stop_pno(struct wpa_supplicant * wpa_s)2381 int wpas_stop_pno(struct wpa_supplicant *wpa_s)
2382 {
2383 	int ret = 0;
2384 
2385 	if (!wpa_s->pno)
2386 		return 0;
2387 
2388 	ret = wpa_supplicant_stop_sched_scan(wpa_s);
2389 
2390 	wpa_s->pno = 0;
2391 	wpa_s->pno_sched_pending = 0;
2392 
2393 	if (wpa_s->wpa_state == WPA_SCANNING)
2394 		wpa_supplicant_req_scan(wpa_s, 0, 0);
2395 
2396 	return ret;
2397 }
2398 
2399 
wpas_mac_addr_rand_scan_clear(struct wpa_supplicant * wpa_s,unsigned int type)2400 void wpas_mac_addr_rand_scan_clear(struct wpa_supplicant *wpa_s,
2401 				    unsigned int type)
2402 {
2403 	type &= MAC_ADDR_RAND_ALL;
2404 	wpa_s->mac_addr_rand_enable &= ~type;
2405 
2406 	if (type & MAC_ADDR_RAND_SCAN) {
2407 		os_free(wpa_s->mac_addr_scan);
2408 		wpa_s->mac_addr_scan = NULL;
2409 	}
2410 
2411 	if (type & MAC_ADDR_RAND_SCHED_SCAN) {
2412 		os_free(wpa_s->mac_addr_sched_scan);
2413 		wpa_s->mac_addr_sched_scan = NULL;
2414 	}
2415 
2416 	if (type & MAC_ADDR_RAND_PNO) {
2417 		os_free(wpa_s->mac_addr_pno);
2418 		wpa_s->mac_addr_pno = NULL;
2419 	}
2420 }
2421 
2422 
wpas_mac_addr_rand_scan_set(struct wpa_supplicant * wpa_s,unsigned int type,const u8 * addr,const u8 * mask)2423 int wpas_mac_addr_rand_scan_set(struct wpa_supplicant *wpa_s,
2424 				unsigned int type, const u8 *addr,
2425 				const u8 *mask)
2426 {
2427 	u8 *tmp = NULL;
2428 
2429 	wpas_mac_addr_rand_scan_clear(wpa_s, type);
2430 
2431 	if (addr) {
2432 		tmp = os_malloc(2 * ETH_ALEN);
2433 		if (!tmp)
2434 			return -1;
2435 		os_memcpy(tmp, addr, ETH_ALEN);
2436 		os_memcpy(tmp + ETH_ALEN, mask, ETH_ALEN);
2437 	}
2438 
2439 	if (type == MAC_ADDR_RAND_SCAN) {
2440 		wpa_s->mac_addr_scan = tmp;
2441 	} else if (type == MAC_ADDR_RAND_SCHED_SCAN) {
2442 		wpa_s->mac_addr_sched_scan = tmp;
2443 	} else if (type == MAC_ADDR_RAND_PNO) {
2444 		wpa_s->mac_addr_pno = tmp;
2445 	} else {
2446 		wpa_printf(MSG_INFO,
2447 			   "scan: Invalid MAC randomization type=0x%x",
2448 			   type);
2449 		os_free(tmp);
2450 		return -1;
2451 	}
2452 
2453 	wpa_s->mac_addr_rand_enable |= type;
2454 	return 0;
2455 }
2456