1/*
2 * BSS table
3 * Copyright (c) 2009-2012, 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 "drivers/driver.h"
15#include "wpa_supplicant_i.h"
16#include "config.h"
17#include "notify.h"
18#include "scan.h"
19#include "bss.h"
20
21
22/**
23 * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
24 */
25#define WPA_BSS_EXPIRATION_PERIOD 10
26
27#define WPA_BSS_FREQ_CHANGED_FLAG	BIT(0)
28#define WPA_BSS_SIGNAL_CHANGED_FLAG	BIT(1)
29#define WPA_BSS_PRIVACY_CHANGED_FLAG	BIT(2)
30#define WPA_BSS_MODE_CHANGED_FLAG	BIT(3)
31#define WPA_BSS_WPAIE_CHANGED_FLAG	BIT(4)
32#define WPA_BSS_RSNIE_CHANGED_FLAG	BIT(5)
33#define WPA_BSS_WPS_CHANGED_FLAG	BIT(6)
34#define WPA_BSS_RATES_CHANGED_FLAG	BIT(7)
35#define WPA_BSS_IES_CHANGED_FLAG	BIT(8)
36
37
38static void wpa_bss_set_hessid(struct wpa_bss *bss)
39{
40#ifdef CONFIG_INTERWORKING
41	const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING);
42	if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) {
43		os_memset(bss->hessid, 0, ETH_ALEN);
44		return;
45	}
46	if (ie[1] == 7)
47		os_memcpy(bss->hessid, ie + 3, ETH_ALEN);
48	else
49		os_memcpy(bss->hessid, ie + 5, ETH_ALEN);
50#endif /* CONFIG_INTERWORKING */
51}
52
53
54/**
55 * wpa_bss_anqp_alloc - Allocate ANQP data structure for a BSS entry
56 * Returns: Allocated ANQP data structure or %NULL on failure
57 *
58 * The allocated ANQP data structure has its users count set to 1. It may be
59 * shared by multiple BSS entries and each shared entry is freed with
60 * wpa_bss_anqp_free().
61 */
62struct wpa_bss_anqp * wpa_bss_anqp_alloc(void)
63{
64	struct wpa_bss_anqp *anqp;
65	anqp = os_zalloc(sizeof(*anqp));
66	if (anqp == NULL)
67		return NULL;
68	anqp->users = 1;
69	return anqp;
70}
71
72
73/**
74 * wpa_bss_anqp_clone - Clone an ANQP data structure
75 * @anqp: ANQP data structure from wpa_bss_anqp_alloc()
76 * Returns: Cloned ANQP data structure or %NULL on failure
77 */
78static struct wpa_bss_anqp * wpa_bss_anqp_clone(struct wpa_bss_anqp *anqp)
79{
80	struct wpa_bss_anqp *n;
81
82	n = os_zalloc(sizeof(*n));
83	if (n == NULL)
84		return NULL;
85
86#define ANQP_DUP(f) if (anqp->f) n->f = wpabuf_dup(anqp->f)
87#ifdef CONFIG_INTERWORKING
88	ANQP_DUP(venue_name);
89	ANQP_DUP(network_auth_type);
90	ANQP_DUP(roaming_consortium);
91	ANQP_DUP(ip_addr_type_availability);
92	ANQP_DUP(nai_realm);
93	ANQP_DUP(anqp_3gpp);
94	ANQP_DUP(domain_name);
95#endif /* CONFIG_INTERWORKING */
96#ifdef CONFIG_HS20
97	ANQP_DUP(hs20_operator_friendly_name);
98	ANQP_DUP(hs20_wan_metrics);
99	ANQP_DUP(hs20_connection_capability);
100	ANQP_DUP(hs20_operating_class);
101#endif /* CONFIG_HS20 */
102#undef ANQP_DUP
103
104	return n;
105}
106
107
108/**
109 * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry
110 * @bss: BSS entry
111 * Returns: 0 on success, -1 on failure
112 *
113 * This function ensures the specific BSS entry has an ANQP data structure that
114 * is not shared with any other BSS entry.
115 */
116int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss)
117{
118	struct wpa_bss_anqp *anqp;
119
120	if (bss->anqp && bss->anqp->users > 1) {
121		/* allocated, but shared - clone an unshared copy */
122		anqp = wpa_bss_anqp_clone(bss->anqp);
123		if (anqp == NULL)
124			return -1;
125		anqp->users = 1;
126		bss->anqp->users--;
127		bss->anqp = anqp;
128		return 0;
129	}
130
131	if (bss->anqp)
132		return 0; /* already allocated and not shared */
133
134	/* not allocated - allocate a new storage area */
135	bss->anqp = wpa_bss_anqp_alloc();
136	return bss->anqp ? 0 : -1;
137}
138
139
140/**
141 * wpa_bss_anqp_free - Free an ANQP data structure
142 * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone()
143 */
144static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp)
145{
146	if (anqp == NULL)
147		return;
148
149	anqp->users--;
150	if (anqp->users > 0) {
151		/* Another BSS entry holds a pointer to this ANQP info */
152		return;
153	}
154
155#ifdef CONFIG_INTERWORKING
156	wpabuf_free(anqp->venue_name);
157	wpabuf_free(anqp->network_auth_type);
158	wpabuf_free(anqp->roaming_consortium);
159	wpabuf_free(anqp->ip_addr_type_availability);
160	wpabuf_free(anqp->nai_realm);
161	wpabuf_free(anqp->anqp_3gpp);
162	wpabuf_free(anqp->domain_name);
163#endif /* CONFIG_INTERWORKING */
164#ifdef CONFIG_HS20
165	wpabuf_free(anqp->hs20_operator_friendly_name);
166	wpabuf_free(anqp->hs20_wan_metrics);
167	wpabuf_free(anqp->hs20_connection_capability);
168	wpabuf_free(anqp->hs20_operating_class);
169#endif /* CONFIG_HS20 */
170
171	os_free(anqp);
172}
173
174
175static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
176			   const char *reason)
177{
178	if (wpa_s->last_scan_res) {
179		unsigned int i;
180		for (i = 0; i < wpa_s->last_scan_res_used; i++) {
181			if (wpa_s->last_scan_res[i] == bss) {
182				os_memmove(&wpa_s->last_scan_res[i],
183					   &wpa_s->last_scan_res[i + 1],
184					   (wpa_s->last_scan_res_used - i - 1)
185					   * sizeof(struct wpa_bss *));
186				wpa_s->last_scan_res_used--;
187				break;
188			}
189		}
190	}
191	dl_list_del(&bss->list);
192	dl_list_del(&bss->list_id);
193	wpa_s->num_bss--;
194	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
195		" SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
196		wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
197	wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
198	wpa_bss_anqp_free(bss->anqp);
199	os_free(bss);
200}
201
202
203/**
204 * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID
205 * @wpa_s: Pointer to wpa_supplicant data
206 * @bssid: BSSID
207 * @ssid: SSID
208 * @ssid_len: Length of @ssid
209 * Returns: Pointer to the BSS entry or %NULL if not found
210 */
211struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
212			     const u8 *ssid, size_t ssid_len)
213{
214	struct wpa_bss *bss;
215	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
216		return NULL;
217	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
218		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
219		    bss->ssid_len == ssid_len &&
220		    os_memcmp(bss->ssid, ssid, ssid_len) == 0)
221			return bss;
222	}
223	return NULL;
224}
225
226
227static void calculate_update_time(const struct os_time *fetch_time,
228				  unsigned int age_ms,
229				  struct os_time *update_time)
230{
231	os_time_t usec;
232
233	update_time->sec = fetch_time->sec;
234	update_time->usec = fetch_time->usec;
235	update_time->sec -= age_ms / 1000;
236	usec = (age_ms % 1000) * 1000;
237	if (update_time->usec < usec) {
238		update_time->sec--;
239		update_time->usec += 1000000;
240	}
241	update_time->usec -= usec;
242}
243
244
245static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src,
246			     struct os_time *fetch_time)
247{
248	dst->flags = src->flags;
249	os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
250	dst->freq = src->freq;
251	dst->beacon_int = src->beacon_int;
252	dst->caps = src->caps;
253	dst->qual = src->qual;
254	dst->noise = src->noise;
255	dst->level = src->level;
256	dst->tsf = src->tsf;
257
258	calculate_update_time(fetch_time, src->age, &dst->last_update);
259}
260
261
262static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
263{
264	struct wpa_ssid *ssid;
265
266	for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
267		if (ssid->ssid == NULL || ssid->ssid_len == 0)
268			continue;
269		if (ssid->ssid_len == bss->ssid_len &&
270		    os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
271			return 1;
272	}
273
274	return 0;
275}
276
277
278static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
279{
280	return bss == wpa_s->current_bss ||
281		os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
282		os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
283}
284
285
286static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
287{
288	struct wpa_bss *bss;
289
290	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
291		if (!wpa_bss_known(wpa_s, bss)) {
292			wpa_bss_remove(wpa_s, bss, __func__);
293			return 0;
294		}
295	}
296
297	return -1;
298}
299
300
301static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
302{
303	struct wpa_bss *bss;
304
305	/*
306	 * Remove the oldest entry that does not match with any configured
307	 * network.
308	 */
309	if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
310		return 0;
311
312	/*
313	 * Remove the oldest entry that isn't currently in use.
314	 */
315	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
316		if (!wpa_bss_in_use(wpa_s, bss)) {
317			wpa_bss_remove(wpa_s, bss, __func__);
318			return 0;
319		}
320	}
321
322	return -1;
323}
324
325
326static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s,
327				    const u8 *ssid, size_t ssid_len,
328				    struct wpa_scan_res *res,
329				    struct os_time *fetch_time)
330{
331	struct wpa_bss *bss;
332
333	bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
334	if (bss == NULL)
335		return NULL;
336	bss->id = wpa_s->bss_next_id++;
337	bss->last_update_idx = wpa_s->bss_update_idx;
338	wpa_bss_copy_res(bss, res, fetch_time);
339	os_memcpy(bss->ssid, ssid, ssid_len);
340	bss->ssid_len = ssid_len;
341	bss->ie_len = res->ie_len;
342	bss->beacon_ie_len = res->beacon_ie_len;
343	os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
344	wpa_bss_set_hessid(bss);
345
346	if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count &&
347	    wpa_bss_remove_oldest(wpa_s) != 0) {
348		wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d "
349			   "because all BSSes are in use. We should normally "
350			   "not get here!", (int) wpa_s->num_bss + 1);
351		wpa_s->conf->bss_max_count = wpa_s->num_bss + 1;
352	}
353
354	dl_list_add_tail(&wpa_s->bss, &bss->list);
355	dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
356	wpa_s->num_bss++;
357	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
358		" SSID '%s'",
359		bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
360	wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
361	return bss;
362}
363
364
365static int are_ies_equal(const struct wpa_bss *old,
366			 const struct wpa_scan_res *new, u32 ie)
367{
368	const u8 *old_ie, *new_ie;
369	struct wpabuf *old_ie_buff = NULL;
370	struct wpabuf *new_ie_buff = NULL;
371	int new_ie_len, old_ie_len, ret, is_multi;
372
373	switch (ie) {
374	case WPA_IE_VENDOR_TYPE:
375		old_ie = wpa_bss_get_vendor_ie(old, ie);
376		new_ie = wpa_scan_get_vendor_ie(new, ie);
377		is_multi = 0;
378		break;
379	case WPS_IE_VENDOR_TYPE:
380		old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
381		new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
382		is_multi = 1;
383		break;
384	case WLAN_EID_RSN:
385	case WLAN_EID_SUPP_RATES:
386	case WLAN_EID_EXT_SUPP_RATES:
387		old_ie = wpa_bss_get_ie(old, ie);
388		new_ie = wpa_scan_get_ie(new, ie);
389		is_multi = 0;
390		break;
391	default:
392		wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
393		return 0;
394	}
395
396	if (is_multi) {
397		/* in case of multiple IEs stored in buffer */
398		old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
399		new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
400		old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
401		new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
402	} else {
403		/* in case of single IE */
404		old_ie_len = old_ie ? old_ie[1] + 2 : 0;
405		new_ie_len = new_ie ? new_ie[1] + 2 : 0;
406	}
407
408	if (!old_ie || !new_ie)
409		ret = !old_ie && !new_ie;
410	else
411		ret = (old_ie_len == new_ie_len &&
412		       os_memcmp(old_ie, new_ie, old_ie_len) == 0);
413
414	wpabuf_free(old_ie_buff);
415	wpabuf_free(new_ie_buff);
416
417	return ret;
418}
419
420
421static u32 wpa_bss_compare_res(const struct wpa_bss *old,
422			       const struct wpa_scan_res *new)
423{
424	u32 changes = 0;
425	int caps_diff = old->caps ^ new->caps;
426
427	if (old->freq != new->freq)
428		changes |= WPA_BSS_FREQ_CHANGED_FLAG;
429
430	if (old->level != new->level)
431		changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
432
433	if (caps_diff & IEEE80211_CAP_PRIVACY)
434		changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
435
436	if (caps_diff & IEEE80211_CAP_IBSS)
437		changes |= WPA_BSS_MODE_CHANGED_FLAG;
438
439	if (old->ie_len == new->ie_len &&
440	    os_memcmp(old + 1, new + 1, old->ie_len) == 0)
441		return changes;
442	changes |= WPA_BSS_IES_CHANGED_FLAG;
443
444	if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
445		changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
446
447	if (!are_ies_equal(old, new, WLAN_EID_RSN))
448		changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
449
450	if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
451		changes |= WPA_BSS_WPS_CHANGED_FLAG;
452
453	if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
454	    !are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
455		changes |= WPA_BSS_RATES_CHANGED_FLAG;
456
457	return changes;
458}
459
460
461static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
462			       const struct wpa_bss *bss)
463{
464	if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
465		wpas_notify_bss_freq_changed(wpa_s, bss->id);
466
467	if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
468		wpas_notify_bss_signal_changed(wpa_s, bss->id);
469
470	if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
471		wpas_notify_bss_privacy_changed(wpa_s, bss->id);
472
473	if (changes & WPA_BSS_MODE_CHANGED_FLAG)
474		wpas_notify_bss_mode_changed(wpa_s, bss->id);
475
476	if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
477		wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
478
479	if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
480		wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
481
482	if (changes & WPA_BSS_WPS_CHANGED_FLAG)
483		wpas_notify_bss_wps_changed(wpa_s, bss->id);
484
485	if (changes & WPA_BSS_IES_CHANGED_FLAG)
486		wpas_notify_bss_ies_changed(wpa_s, bss->id);
487
488	if (changes & WPA_BSS_RATES_CHANGED_FLAG)
489		wpas_notify_bss_rates_changed(wpa_s, bss->id);
490}
491
492
493static struct wpa_bss *
494wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
495	       struct wpa_scan_res *res, struct os_time *fetch_time)
496{
497	u32 changes;
498
499	changes = wpa_bss_compare_res(bss, res);
500	bss->scan_miss_count = 0;
501	bss->last_update_idx = wpa_s->bss_update_idx;
502	wpa_bss_copy_res(bss, res, fetch_time);
503	/* Move the entry to the end of the list */
504	dl_list_del(&bss->list);
505	if (bss->ie_len + bss->beacon_ie_len >=
506	    res->ie_len + res->beacon_ie_len) {
507		os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
508		bss->ie_len = res->ie_len;
509		bss->beacon_ie_len = res->beacon_ie_len;
510	} else {
511		struct wpa_bss *nbss;
512		struct dl_list *prev = bss->list_id.prev;
513		dl_list_del(&bss->list_id);
514		nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
515				  res->beacon_ie_len);
516		if (nbss) {
517			unsigned int i;
518			for (i = 0; i < wpa_s->last_scan_res_used; i++) {
519				if (wpa_s->last_scan_res[i] == bss) {
520					wpa_s->last_scan_res[i] = nbss;
521					break;
522				}
523			}
524			if (wpa_s->current_bss == bss)
525				wpa_s->current_bss = nbss;
526			bss = nbss;
527			os_memcpy(bss + 1, res + 1,
528				  res->ie_len + res->beacon_ie_len);
529			bss->ie_len = res->ie_len;
530			bss->beacon_ie_len = res->beacon_ie_len;
531		}
532		dl_list_add(prev, &bss->list_id);
533	}
534	if (changes & WPA_BSS_IES_CHANGED_FLAG)
535		wpa_bss_set_hessid(bss);
536	dl_list_add_tail(&wpa_s->bss, &bss->list);
537
538	notify_bss_changes(wpa_s, changes, bss);
539
540	return bss;
541}
542
543
544/**
545 * wpa_bss_update_start - Start a BSS table update from scan results
546 * @wpa_s: Pointer to wpa_supplicant data
547 *
548 * This function is called at the start of each BSS table update round for new
549 * scan results. The actual scan result entries are indicated with calls to
550 * wpa_bss_update_scan_res() and the update round is finished with a call to
551 * wpa_bss_update_end().
552 */
553void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
554{
555	wpa_s->bss_update_idx++;
556	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
557		wpa_s->bss_update_idx);
558	wpa_s->last_scan_res_used = 0;
559}
560
561
562/**
563 * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result
564 * @wpa_s: Pointer to wpa_supplicant data
565 * @res: Scan result
566 * @fetch_time: Time when the result was fetched from the driver
567 *
568 * This function updates a BSS table entry (or adds one) based on a scan result.
569 * This is called separately for each scan result between the calls to
570 * wpa_bss_update_start() and wpa_bss_update_end().
571 */
572void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
573			     struct wpa_scan_res *res,
574			     struct os_time *fetch_time)
575{
576	const u8 *ssid, *p2p;
577	struct wpa_bss *bss;
578
579	if (wpa_s->conf->ignore_old_scan_res) {
580		struct os_time update;
581		calculate_update_time(fetch_time, res->age, &update);
582		if (os_time_before(&update, &wpa_s->scan_trigger_time)) {
583			struct os_time age;
584			os_time_sub(&wpa_s->scan_trigger_time, &update, &age);
585			wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS "
586				"table entry that is %u.%06u seconds older "
587				"than our scan trigger",
588				(unsigned int) age.sec,
589				(unsigned int) age.usec);
590			return;
591		}
592	}
593
594	ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
595	if (ssid == NULL) {
596		wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
597			MACSTR, MAC2STR(res->bssid));
598		return;
599	}
600	if (ssid[1] > 32) {
601		wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
602			MACSTR, MAC2STR(res->bssid));
603		return;
604	}
605
606	p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
607#ifdef CONFIG_P2P
608	if (p2p == NULL &&
609	    wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
610		/*
611		 * If it's a P2P specific interface, then don't update
612		 * the scan result without a P2P IE.
613		 */
614		wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
615			   " update for P2P interface", MAC2STR(res->bssid));
616		return;
617	}
618#endif /* CONFIG_P2P */
619	if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
620	    os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
621		return; /* Skip P2P listen discovery results here */
622
623	/* TODO: add option for ignoring BSSes we are not interested in
624	 * (to save memory) */
625	bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
626	if (bss == NULL)
627		bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time);
628	else
629		bss = wpa_bss_update(wpa_s, bss, res, fetch_time);
630
631	if (bss == NULL)
632		return;
633	if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) {
634		struct wpa_bss **n;
635		unsigned int siz;
636		if (wpa_s->last_scan_res_size == 0)
637			siz = 32;
638		else
639			siz = wpa_s->last_scan_res_size * 2;
640		n = os_realloc_array(wpa_s->last_scan_res, siz,
641				     sizeof(struct wpa_bss *));
642		if (n == NULL)
643			return;
644		wpa_s->last_scan_res = n;
645		wpa_s->last_scan_res_size = siz;
646	}
647
648	wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss;
649}
650
651
652static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
653				    const struct scan_info *info)
654{
655	int found;
656	size_t i;
657
658	if (info == NULL)
659		return 1;
660
661	if (info->num_freqs) {
662		found = 0;
663		for (i = 0; i < info->num_freqs; i++) {
664			if (bss->freq == info->freqs[i]) {
665				found = 1;
666				break;
667			}
668		}
669		if (!found)
670			return 0;
671	}
672
673	if (info->num_ssids) {
674		found = 0;
675		for (i = 0; i < info->num_ssids; i++) {
676			const struct wpa_driver_scan_ssid *s = &info->ssids[i];
677			if ((s->ssid == NULL || s->ssid_len == 0) ||
678			    (s->ssid_len == bss->ssid_len &&
679			     os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
680			     0)) {
681				found = 1;
682				break;
683			}
684		}
685		if (!found)
686			return 0;
687	}
688
689	return 1;
690}
691
692
693/**
694 * wpa_bss_update_end - End a BSS table update from scan results
695 * @wpa_s: Pointer to wpa_supplicant data
696 * @info: Information about scan parameters
697 * @new_scan: Whether this update round was based on a new scan
698 *
699 * This function is called at the end of each BSS table update round for new
700 * scan results. The start of the update was indicated with a call to
701 * wpa_bss_update_start().
702 */
703void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
704			int new_scan)
705{
706	struct wpa_bss *bss, *n;
707
708	wpa_s->last_scan_full = 0;
709	os_get_time(&wpa_s->last_scan);
710	if (!new_scan)
711		return; /* do not expire entries without new scan */
712
713	if (info && !info->aborted && !info->freqs) {
714		size_t i;
715		if (info->num_ssids == 0) {
716			wpa_s->last_scan_full = 1;
717		} else {
718			for (i = 0; i < info->num_ssids; i++) {
719				if (info->ssids[i].ssid == NULL ||
720				    info->ssids[i].ssid_len == 0) {
721					wpa_s->last_scan_full = 1;
722					break;
723				}
724			}
725		}
726	}
727
728	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
729		if (wpa_bss_in_use(wpa_s, bss))
730			continue;
731		if (!wpa_bss_included_in_scan(bss, info))
732			continue; /* expire only BSSes that were scanned */
733		if (bss->last_update_idx < wpa_s->bss_update_idx)
734			bss->scan_miss_count++;
735		if (bss->scan_miss_count >=
736		    wpa_s->conf->bss_expiration_scan_count) {
737			wpa_bss_remove(wpa_s, bss, "no match in scan");
738		}
739	}
740
741	wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u "
742		   "last_scan_full=%d",
743		   wpa_s->last_scan_res_used, wpa_s->last_scan_res_size,
744		   wpa_s->last_scan_full);
745}
746
747
748/**
749 * wpa_bss_flush_by_age - Flush old BSS entries
750 * @wpa_s: Pointer to wpa_supplicant data
751 * @age: Maximum entry age in seconds
752 *
753 * Remove BSS entries that have not been updated during the last @age seconds.
754 */
755void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
756{
757	struct wpa_bss *bss, *n;
758	struct os_time t;
759
760	if (dl_list_empty(&wpa_s->bss))
761		return;
762
763	os_get_time(&t);
764	t.sec -= age;
765
766	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
767		if (wpa_bss_in_use(wpa_s, bss))
768			continue;
769
770		if (os_time_before(&bss->last_update, &t)) {
771			wpa_bss_remove(wpa_s, bss, __func__);
772		} else
773			break;
774	}
775}
776
777
778static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
779{
780	struct wpa_supplicant *wpa_s = eloop_ctx;
781
782	wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age);
783	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
784			       wpa_bss_timeout, wpa_s, NULL);
785}
786
787
788/**
789 * wpa_bss_init - Initialize BSS table
790 * @wpa_s: Pointer to wpa_supplicant data
791 * Returns: 0 on success, -1 on failure
792 *
793 * This prepares BSS table lists and timer for periodic updates. The BSS table
794 * is deinitialized with wpa_bss_deinit() once not needed anymore.
795 */
796int wpa_bss_init(struct wpa_supplicant *wpa_s)
797{
798	dl_list_init(&wpa_s->bss);
799	dl_list_init(&wpa_s->bss_id);
800	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
801			       wpa_bss_timeout, wpa_s, NULL);
802	return 0;
803}
804
805
806/**
807 * wpa_bss_flush - Flush all unused BSS entries
808 * @wpa_s: Pointer to wpa_supplicant data
809 */
810void wpa_bss_flush(struct wpa_supplicant *wpa_s)
811{
812	struct wpa_bss *bss, *n;
813
814	if (wpa_s->bss.next == NULL)
815		return; /* BSS table not yet initialized */
816
817	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
818		if (wpa_bss_in_use(wpa_s, bss))
819			continue;
820		wpa_bss_remove(wpa_s, bss, __func__);
821	}
822}
823
824
825/**
826 * wpa_bss_deinit - Deinitialize BSS table
827 * @wpa_s: Pointer to wpa_supplicant data
828 */
829void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
830{
831	eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
832	wpa_bss_flush(wpa_s);
833}
834
835
836/**
837 * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID
838 * @wpa_s: Pointer to wpa_supplicant data
839 * @bssid: BSSID
840 * Returns: Pointer to the BSS entry or %NULL if not found
841 */
842struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
843				   const u8 *bssid)
844{
845	struct wpa_bss *bss;
846	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
847		return NULL;
848	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
849		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
850			return bss;
851	}
852	return NULL;
853}
854
855
856/**
857 * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID
858 * @wpa_s: Pointer to wpa_supplicant data
859 * @bssid: BSSID
860 * Returns: Pointer to the BSS entry or %NULL if not found
861 *
862 * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to
863 * find the entry that has the most recent update. This can help in finding the
864 * correct entry in cases where the SSID of the AP may have changed recently
865 * (e.g., in WPS reconfiguration cases).
866 */
867struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s,
868					  const u8 *bssid)
869{
870	struct wpa_bss *bss, *found = NULL;
871	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
872		return NULL;
873	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
874		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0)
875			continue;
876		if (found == NULL ||
877		    os_time_before(&found->last_update, &bss->last_update))
878			found = bss;
879	}
880	return found;
881}
882
883
884#ifdef CONFIG_P2P
885/**
886 * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr
887 * @wpa_s: Pointer to wpa_supplicant data
888 * @dev_addr: P2P Device Address of the GO
889 * Returns: Pointer to the BSS entry or %NULL if not found
890 */
891struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
892					  const u8 *dev_addr)
893{
894	struct wpa_bss *bss;
895	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
896		u8 addr[ETH_ALEN];
897		if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
898				       addr) == 0 &&
899		    os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
900			return bss;
901	}
902	return NULL;
903}
904#endif /* CONFIG_P2P */
905
906
907/**
908 * wpa_bss_get_id - Fetch a BSS table entry based on identifier
909 * @wpa_s: Pointer to wpa_supplicant data
910 * @id: Unique identifier (struct wpa_bss::id) assigned for the entry
911 * Returns: Pointer to the BSS entry or %NULL if not found
912 */
913struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
914{
915	struct wpa_bss *bss;
916	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
917		if (bss->id == id)
918			return bss;
919	}
920	return NULL;
921}
922
923
924/**
925 * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range
926 * @wpa_s: Pointer to wpa_supplicant data
927 * @idf: Smallest allowed identifier assigned for the entry
928 * @idf: Largest allowed identifier assigned for the entry
929 * Returns: Pointer to the BSS entry or %NULL if not found
930 *
931 * This function is similar to wpa_bss_get_id() but allows a BSS entry with the
932 * smallest id value to be fetched within the specified range without the
933 * caller having to know the exact id.
934 */
935struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s,
936				      unsigned int idf, unsigned int idl)
937{
938	struct wpa_bss *bss;
939	dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) {
940		if (bss->id >= idf && bss->id <= idl)
941			return bss;
942	}
943	return NULL;
944}
945
946
947/**
948 * wpa_bss_get_ie - Fetch a specified information element from a BSS entry
949 * @bss: BSS table entry
950 * @ie: Information element identitifier (WLAN_EID_*)
951 * Returns: Pointer to the information element (id field) or %NULL if not found
952 *
953 * This function returns the first matching information element in the BSS
954 * entry.
955 */
956const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
957{
958	const u8 *end, *pos;
959
960	pos = (const u8 *) (bss + 1);
961	end = pos + bss->ie_len;
962
963	while (pos + 1 < end) {
964		if (pos + 2 + pos[1] > end)
965			break;
966		if (pos[0] == ie)
967			return pos;
968		pos += 2 + pos[1];
969	}
970
971	return NULL;
972}
973
974
975/**
976 * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry
977 * @bss: BSS table entry
978 * @vendor_type: Vendor type (four octets starting the IE payload)
979 * Returns: Pointer to the information element (id field) or %NULL if not found
980 *
981 * This function returns the first matching information element in the BSS
982 * entry.
983 */
984const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
985{
986	const u8 *end, *pos;
987
988	pos = (const u8 *) (bss + 1);
989	end = pos + bss->ie_len;
990
991	while (pos + 1 < end) {
992		if (pos + 2 + pos[1] > end)
993			break;
994		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
995		    vendor_type == WPA_GET_BE32(&pos[2]))
996			return pos;
997		pos += 2 + pos[1];
998	}
999
1000	return NULL;
1001}
1002
1003
1004/**
1005 * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry
1006 * @bss: BSS table entry
1007 * @vendor_type: Vendor type (four octets starting the IE payload)
1008 * Returns: Pointer to the information element payload or %NULL if not found
1009 *
1010 * This function returns concatenated payload of possibly fragmented vendor
1011 * specific information elements in the BSS entry. The caller is responsible for
1012 * freeing the returned buffer.
1013 */
1014struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
1015					    u32 vendor_type)
1016{
1017	struct wpabuf *buf;
1018	const u8 *end, *pos;
1019
1020	buf = wpabuf_alloc(bss->ie_len);
1021	if (buf == NULL)
1022		return NULL;
1023
1024	pos = (const u8 *) (bss + 1);
1025	end = pos + bss->ie_len;
1026
1027	while (pos + 1 < end) {
1028		if (pos + 2 + pos[1] > end)
1029			break;
1030		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1031		    vendor_type == WPA_GET_BE32(&pos[2]))
1032			wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1033		pos += 2 + pos[1];
1034	}
1035
1036	if (wpabuf_len(buf) == 0) {
1037		wpabuf_free(buf);
1038		buf = NULL;
1039	}
1040
1041	return buf;
1042}
1043
1044
1045/**
1046 * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry
1047 * @bss: BSS table entry
1048 * @vendor_type: Vendor type (four octets starting the IE payload)
1049 * Returns: Pointer to the information element payload or %NULL if not found
1050 *
1051 * This function returns concatenated payload of possibly fragmented vendor
1052 * specific information elements in the BSS entry. The caller is responsible for
1053 * freeing the returned buffer.
1054 *
1055 * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only
1056 * from Beacon frames instead of either Beacon or Probe Response frames.
1057 */
1058struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss,
1059						   u32 vendor_type)
1060{
1061	struct wpabuf *buf;
1062	const u8 *end, *pos;
1063
1064	buf = wpabuf_alloc(bss->beacon_ie_len);
1065	if (buf == NULL)
1066		return NULL;
1067
1068	pos = (const u8 *) (bss + 1);
1069	pos += bss->ie_len;
1070	end = pos + bss->beacon_ie_len;
1071
1072	while (pos + 1 < end) {
1073		if (pos + 2 + pos[1] > end)
1074			break;
1075		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
1076		    vendor_type == WPA_GET_BE32(&pos[2]))
1077			wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
1078		pos += 2 + pos[1];
1079	}
1080
1081	if (wpabuf_len(buf) == 0) {
1082		wpabuf_free(buf);
1083		buf = NULL;
1084	}
1085
1086	return buf;
1087}
1088
1089
1090/**
1091 * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS
1092 * @bss: BSS table entry
1093 * Returns: Maximum legacy rate in units of 500 kbps
1094 */
1095int wpa_bss_get_max_rate(const struct wpa_bss *bss)
1096{
1097	int rate = 0;
1098	const u8 *ie;
1099	int i;
1100
1101	ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
1102	for (i = 0; ie && i < ie[1]; i++) {
1103		if ((ie[i + 2] & 0x7f) > rate)
1104			rate = ie[i + 2] & 0x7f;
1105	}
1106
1107	ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
1108	for (i = 0; ie && i < ie[1]; i++) {
1109		if ((ie[i + 2] & 0x7f) > rate)
1110			rate = ie[i + 2] & 0x7f;
1111	}
1112
1113	return rate;
1114}
1115
1116
1117/**
1118 * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS
1119 * @bss: BSS table entry
1120 * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps)
1121 * Returns: number of legacy TX rates or -1 on failure
1122 *
1123 * The caller is responsible for freeing the returned buffer with os_free() in
1124 * case of success.
1125 */
1126int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
1127{
1128	const u8 *ie, *ie2;
1129	int i, j;
1130	unsigned int len;
1131	u8 *r;
1132
1133	ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
1134	ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
1135
1136	len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
1137
1138	r = os_malloc(len);
1139	if (!r)
1140		return -1;
1141
1142	for (i = 0; ie && i < ie[1]; i++)
1143		r[i] = ie[i + 2] & 0x7f;
1144
1145	for (j = 0; ie2 && j < ie2[1]; j++)
1146		r[i + j] = ie2[j + 2] & 0x7f;
1147
1148	*rates = r;
1149	return len;
1150}
1151