xref: /linux/net/wireless/scan.c (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * cfg80211 scan result handling
4  *
5  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  * Copyright 2016	Intel Deutschland GmbH
8  * Copyright (C) 2018-2021 Intel Corporation
9  */
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/netdevice.h>
14 #include <linux/wireless.h>
15 #include <linux/nl80211.h>
16 #include <linux/etherdevice.h>
17 #include <linux/crc32.h>
18 #include <linux/bitfield.h>
19 #include <net/arp.h>
20 #include <net/cfg80211.h>
21 #include <net/cfg80211-wext.h>
22 #include <net/iw_handler.h>
23 #include "core.h"
24 #include "nl80211.h"
25 #include "wext-compat.h"
26 #include "rdev-ops.h"
27 
28 /**
29  * DOC: BSS tree/list structure
30  *
31  * At the top level, the BSS list is kept in both a list in each
32  * registered device (@bss_list) as well as an RB-tree for faster
33  * lookup. In the RB-tree, entries can be looked up using their
34  * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
35  * for other BSSes.
36  *
37  * Due to the possibility of hidden SSIDs, there's a second level
38  * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
39  * The hidden_list connects all BSSes belonging to a single AP
40  * that has a hidden SSID, and connects beacon and probe response
41  * entries. For a probe response entry for a hidden SSID, the
42  * hidden_beacon_bss pointer points to the BSS struct holding the
43  * beacon's information.
44  *
45  * Reference counting is done for all these references except for
46  * the hidden_list, so that a beacon BSS struct that is otherwise
47  * not referenced has one reference for being on the bss_list and
48  * one for each probe response entry that points to it using the
49  * hidden_beacon_bss pointer. When a BSS struct that has such a
50  * pointer is get/put, the refcount update is also propagated to
51  * the referenced struct, this ensure that it cannot get removed
52  * while somebody is using the probe response version.
53  *
54  * Note that the hidden_beacon_bss pointer never changes, due to
55  * the reference counting. Therefore, no locking is needed for
56  * it.
57  *
58  * Also note that the hidden_beacon_bss pointer is only relevant
59  * if the driver uses something other than the IEs, e.g. private
60  * data stored in the BSS struct, since the beacon IEs are
61  * also linked into the probe response struct.
62  */
63 
64 /*
65  * Limit the number of BSS entries stored in mac80211. Each one is
66  * a bit over 4k at most, so this limits to roughly 4-5M of memory.
67  * If somebody wants to really attack this though, they'd likely
68  * use small beacons, and only one type of frame, limiting each of
69  * the entries to a much smaller size (in order to generate more
70  * entries in total, so overhead is bigger.)
71  */
72 static int bss_entries_limit = 1000;
73 module_param(bss_entries_limit, int, 0644);
74 MODULE_PARM_DESC(bss_entries_limit,
75                  "limit to number of scan BSS entries (per wiphy, default 1000)");
76 
77 #define IEEE80211_SCAN_RESULT_EXPIRE	(30 * HZ)
78 
79 /**
80  * struct cfg80211_colocated_ap - colocated AP information
81  *
82  * @list: linked list to all colocated aPS
83  * @bssid: BSSID of the reported AP
84  * @ssid: SSID of the reported AP
85  * @ssid_len: length of the ssid
86  * @center_freq: frequency the reported AP is on
87  * @unsolicited_probe: the reported AP is part of an ESS, where all the APs
88  *	that operate in the same channel as the reported AP and that might be
89  *	detected by a STA receiving this frame, are transmitting unsolicited
90  *	Probe Response frames every 20 TUs
91  * @oct_recommended: OCT is recommended to exchange MMPDUs with the reported AP
92  * @same_ssid: the reported AP has the same SSID as the reporting AP
93  * @multi_bss: the reported AP is part of a multiple BSSID set
94  * @transmitted_bssid: the reported AP is the transmitting BSSID
95  * @colocated_ess: all the APs that share the same ESS as the reported AP are
96  *	colocated and can be discovered via legacy bands.
97  * @short_ssid_valid: short_ssid is valid and can be used
98  * @short_ssid: the short SSID for this SSID
99  */
100 struct cfg80211_colocated_ap {
101 	struct list_head list;
102 	u8 bssid[ETH_ALEN];
103 	u8 ssid[IEEE80211_MAX_SSID_LEN];
104 	size_t ssid_len;
105 	u32 short_ssid;
106 	u32 center_freq;
107 	u8 unsolicited_probe:1,
108 	   oct_recommended:1,
109 	   same_ssid:1,
110 	   multi_bss:1,
111 	   transmitted_bssid:1,
112 	   colocated_ess:1,
113 	   short_ssid_valid:1;
114 };
115 
116 static void bss_free(struct cfg80211_internal_bss *bss)
117 {
118 	struct cfg80211_bss_ies *ies;
119 
120 	if (WARN_ON(atomic_read(&bss->hold)))
121 		return;
122 
123 	ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
124 	if (ies && !bss->pub.hidden_beacon_bss)
125 		kfree_rcu(ies, rcu_head);
126 	ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
127 	if (ies)
128 		kfree_rcu(ies, rcu_head);
129 
130 	/*
131 	 * This happens when the module is removed, it doesn't
132 	 * really matter any more save for completeness
133 	 */
134 	if (!list_empty(&bss->hidden_list))
135 		list_del(&bss->hidden_list);
136 
137 	kfree(bss);
138 }
139 
140 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
141 			       struct cfg80211_internal_bss *bss)
142 {
143 	lockdep_assert_held(&rdev->bss_lock);
144 
145 	bss->refcount++;
146 	if (bss->pub.hidden_beacon_bss) {
147 		bss = container_of(bss->pub.hidden_beacon_bss,
148 				   struct cfg80211_internal_bss,
149 				   pub);
150 		bss->refcount++;
151 	}
152 	if (bss->pub.transmitted_bss) {
153 		bss = container_of(bss->pub.transmitted_bss,
154 				   struct cfg80211_internal_bss,
155 				   pub);
156 		bss->refcount++;
157 	}
158 }
159 
160 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
161 			       struct cfg80211_internal_bss *bss)
162 {
163 	lockdep_assert_held(&rdev->bss_lock);
164 
165 	if (bss->pub.hidden_beacon_bss) {
166 		struct cfg80211_internal_bss *hbss;
167 		hbss = container_of(bss->pub.hidden_beacon_bss,
168 				    struct cfg80211_internal_bss,
169 				    pub);
170 		hbss->refcount--;
171 		if (hbss->refcount == 0)
172 			bss_free(hbss);
173 	}
174 
175 	if (bss->pub.transmitted_bss) {
176 		struct cfg80211_internal_bss *tbss;
177 
178 		tbss = container_of(bss->pub.transmitted_bss,
179 				    struct cfg80211_internal_bss,
180 				    pub);
181 		tbss->refcount--;
182 		if (tbss->refcount == 0)
183 			bss_free(tbss);
184 	}
185 
186 	bss->refcount--;
187 	if (bss->refcount == 0)
188 		bss_free(bss);
189 }
190 
191 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
192 				  struct cfg80211_internal_bss *bss)
193 {
194 	lockdep_assert_held(&rdev->bss_lock);
195 
196 	if (!list_empty(&bss->hidden_list)) {
197 		/*
198 		 * don't remove the beacon entry if it has
199 		 * probe responses associated with it
200 		 */
201 		if (!bss->pub.hidden_beacon_bss)
202 			return false;
203 		/*
204 		 * if it's a probe response entry break its
205 		 * link to the other entries in the group
206 		 */
207 		list_del_init(&bss->hidden_list);
208 	}
209 
210 	list_del_init(&bss->list);
211 	list_del_init(&bss->pub.nontrans_list);
212 	rb_erase(&bss->rbn, &rdev->bss_tree);
213 	rdev->bss_entries--;
214 	WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
215 		  "rdev bss entries[%d]/list[empty:%d] corruption\n",
216 		  rdev->bss_entries, list_empty(&rdev->bss_list));
217 	bss_ref_put(rdev, bss);
218 	return true;
219 }
220 
221 bool cfg80211_is_element_inherited(const struct element *elem,
222 				   const struct element *non_inherit_elem)
223 {
224 	u8 id_len, ext_id_len, i, loop_len, id;
225 	const u8 *list;
226 
227 	if (elem->id == WLAN_EID_MULTIPLE_BSSID)
228 		return false;
229 
230 	if (!non_inherit_elem || non_inherit_elem->datalen < 2)
231 		return true;
232 
233 	/*
234 	 * non inheritance element format is:
235 	 * ext ID (56) | IDs list len | list | extension IDs list len | list
236 	 * Both lists are optional. Both lengths are mandatory.
237 	 * This means valid length is:
238 	 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
239 	 */
240 	id_len = non_inherit_elem->data[1];
241 	if (non_inherit_elem->datalen < 3 + id_len)
242 		return true;
243 
244 	ext_id_len = non_inherit_elem->data[2 + id_len];
245 	if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
246 		return true;
247 
248 	if (elem->id == WLAN_EID_EXTENSION) {
249 		if (!ext_id_len)
250 			return true;
251 		loop_len = ext_id_len;
252 		list = &non_inherit_elem->data[3 + id_len];
253 		id = elem->data[0];
254 	} else {
255 		if (!id_len)
256 			return true;
257 		loop_len = id_len;
258 		list = &non_inherit_elem->data[2];
259 		id = elem->id;
260 	}
261 
262 	for (i = 0; i < loop_len; i++) {
263 		if (list[i] == id)
264 			return false;
265 	}
266 
267 	return true;
268 }
269 EXPORT_SYMBOL(cfg80211_is_element_inherited);
270 
271 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
272 				  const u8 *subelement, size_t subie_len,
273 				  u8 *new_ie, gfp_t gfp)
274 {
275 	u8 *pos, *tmp;
276 	const u8 *tmp_old, *tmp_new;
277 	const struct element *non_inherit_elem;
278 	u8 *sub_copy;
279 
280 	/* copy subelement as we need to change its content to
281 	 * mark an ie after it is processed.
282 	 */
283 	sub_copy = kmemdup(subelement, subie_len, gfp);
284 	if (!sub_copy)
285 		return 0;
286 
287 	pos = &new_ie[0];
288 
289 	/* set new ssid */
290 	tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
291 	if (tmp_new) {
292 		memcpy(pos, tmp_new, tmp_new[1] + 2);
293 		pos += (tmp_new[1] + 2);
294 	}
295 
296 	/* get non inheritance list if exists */
297 	non_inherit_elem =
298 		cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
299 				       sub_copy, subie_len);
300 
301 	/* go through IEs in ie (skip SSID) and subelement,
302 	 * merge them into new_ie
303 	 */
304 	tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
305 	tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
306 
307 	while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {
308 		if (tmp_old[0] == 0) {
309 			tmp_old++;
310 			continue;
311 		}
312 
313 		if (tmp_old[0] == WLAN_EID_EXTENSION)
314 			tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
315 							 subie_len);
316 		else
317 			tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
318 						     subie_len);
319 
320 		if (!tmp) {
321 			const struct element *old_elem = (void *)tmp_old;
322 
323 			/* ie in old ie but not in subelement */
324 			if (cfg80211_is_element_inherited(old_elem,
325 							  non_inherit_elem)) {
326 				memcpy(pos, tmp_old, tmp_old[1] + 2);
327 				pos += tmp_old[1] + 2;
328 			}
329 		} else {
330 			/* ie in transmitting ie also in subelement,
331 			 * copy from subelement and flag the ie in subelement
332 			 * as copied (by setting eid field to WLAN_EID_SSID,
333 			 * which is skipped anyway).
334 			 * For vendor ie, compare OUI + type + subType to
335 			 * determine if they are the same ie.
336 			 */
337 			if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
338 				if (!memcmp(tmp_old + 2, tmp + 2, 5)) {
339 					/* same vendor ie, copy from
340 					 * subelement
341 					 */
342 					memcpy(pos, tmp, tmp[1] + 2);
343 					pos += tmp[1] + 2;
344 					tmp[0] = WLAN_EID_SSID;
345 				} else {
346 					memcpy(pos, tmp_old, tmp_old[1] + 2);
347 					pos += tmp_old[1] + 2;
348 				}
349 			} else {
350 				/* copy ie from subelement into new ie */
351 				memcpy(pos, tmp, tmp[1] + 2);
352 				pos += tmp[1] + 2;
353 				tmp[0] = WLAN_EID_SSID;
354 			}
355 		}
356 
357 		if (tmp_old + tmp_old[1] + 2 - ie == ielen)
358 			break;
359 
360 		tmp_old += tmp_old[1] + 2;
361 	}
362 
363 	/* go through subelement again to check if there is any ie not
364 	 * copied to new ie, skip ssid, capability, bssid-index ie
365 	 */
366 	tmp_new = sub_copy;
367 	while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
368 		if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
369 		      tmp_new[0] == WLAN_EID_SSID)) {
370 			memcpy(pos, tmp_new, tmp_new[1] + 2);
371 			pos += tmp_new[1] + 2;
372 		}
373 		if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
374 			break;
375 		tmp_new += tmp_new[1] + 2;
376 	}
377 
378 	kfree(sub_copy);
379 	return pos - new_ie;
380 }
381 
382 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
383 		   const u8 *ssid, size_t ssid_len)
384 {
385 	const struct cfg80211_bss_ies *ies;
386 	const struct element *ssid_elem;
387 
388 	if (bssid && !ether_addr_equal(a->bssid, bssid))
389 		return false;
390 
391 	if (!ssid)
392 		return true;
393 
394 	ies = rcu_access_pointer(a->ies);
395 	if (!ies)
396 		return false;
397 	ssid_elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
398 	if (!ssid_elem)
399 		return false;
400 	if (ssid_elem->datalen != ssid_len)
401 		return false;
402 	return memcmp(ssid_elem->data, ssid, ssid_len) == 0;
403 }
404 
405 static int
406 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
407 			   struct cfg80211_bss *nontrans_bss)
408 {
409 	const struct element *ssid_elem;
410 	struct cfg80211_bss *bss = NULL;
411 
412 	rcu_read_lock();
413 	ssid_elem = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
414 	if (!ssid_elem) {
415 		rcu_read_unlock();
416 		return -EINVAL;
417 	}
418 
419 	/* check if nontrans_bss is in the list */
420 	list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
421 		if (is_bss(bss, nontrans_bss->bssid, ssid_elem->data,
422 			   ssid_elem->datalen)) {
423 			rcu_read_unlock();
424 			return 0;
425 		}
426 	}
427 
428 	rcu_read_unlock();
429 
430 	/* add to the list */
431 	list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
432 	return 0;
433 }
434 
435 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
436 				  unsigned long expire_time)
437 {
438 	struct cfg80211_internal_bss *bss, *tmp;
439 	bool expired = false;
440 
441 	lockdep_assert_held(&rdev->bss_lock);
442 
443 	list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
444 		if (atomic_read(&bss->hold))
445 			continue;
446 		if (!time_after(expire_time, bss->ts))
447 			continue;
448 
449 		if (__cfg80211_unlink_bss(rdev, bss))
450 			expired = true;
451 	}
452 
453 	if (expired)
454 		rdev->bss_generation++;
455 }
456 
457 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
458 {
459 	struct cfg80211_internal_bss *bss, *oldest = NULL;
460 	bool ret;
461 
462 	lockdep_assert_held(&rdev->bss_lock);
463 
464 	list_for_each_entry(bss, &rdev->bss_list, list) {
465 		if (atomic_read(&bss->hold))
466 			continue;
467 
468 		if (!list_empty(&bss->hidden_list) &&
469 		    !bss->pub.hidden_beacon_bss)
470 			continue;
471 
472 		if (oldest && time_before(oldest->ts, bss->ts))
473 			continue;
474 		oldest = bss;
475 	}
476 
477 	if (WARN_ON(!oldest))
478 		return false;
479 
480 	/*
481 	 * The callers make sure to increase rdev->bss_generation if anything
482 	 * gets removed (and a new entry added), so there's no need to also do
483 	 * it here.
484 	 */
485 
486 	ret = __cfg80211_unlink_bss(rdev, oldest);
487 	WARN_ON(!ret);
488 	return ret;
489 }
490 
491 static u8 cfg80211_parse_bss_param(u8 data,
492 				   struct cfg80211_colocated_ap *coloc_ap)
493 {
494 	coloc_ap->oct_recommended =
495 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
496 	coloc_ap->same_ssid =
497 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
498 	coloc_ap->multi_bss =
499 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
500 	coloc_ap->transmitted_bssid =
501 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
502 	coloc_ap->unsolicited_probe =
503 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
504 	coloc_ap->colocated_ess =
505 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
506 
507 	return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
508 }
509 
510 static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
511 				    const struct element **elem, u32 *s_ssid)
512 {
513 
514 	*elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
515 	if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
516 		return -EINVAL;
517 
518 	*s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
519 	return 0;
520 }
521 
522 static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
523 {
524 	struct cfg80211_colocated_ap *ap, *tmp_ap;
525 
526 	list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
527 		list_del(&ap->list);
528 		kfree(ap);
529 	}
530 }
531 
532 static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
533 				  const u8 *pos, u8 length,
534 				  const struct element *ssid_elem,
535 				  int s_ssid_tmp)
536 {
537 	/* skip the TBTT offset */
538 	pos++;
539 
540 	memcpy(entry->bssid, pos, ETH_ALEN);
541 	pos += ETH_ALEN;
542 
543 	if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) {
544 		memcpy(&entry->short_ssid, pos,
545 		       sizeof(entry->short_ssid));
546 		entry->short_ssid_valid = true;
547 		pos += 4;
548 	}
549 
550 	/* skip non colocated APs */
551 	if (!cfg80211_parse_bss_param(*pos, entry))
552 		return -EINVAL;
553 	pos++;
554 
555 	if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) {
556 		/*
557 		 * no information about the short ssid. Consider the entry valid
558 		 * for now. It would later be dropped in case there are explicit
559 		 * SSIDs that need to be matched
560 		 */
561 		if (!entry->same_ssid)
562 			return 0;
563 	}
564 
565 	if (entry->same_ssid) {
566 		entry->short_ssid = s_ssid_tmp;
567 		entry->short_ssid_valid = true;
568 
569 		/*
570 		 * This is safe because we validate datalen in
571 		 * cfg80211_parse_colocated_ap(), before calling this
572 		 * function.
573 		 */
574 		memcpy(&entry->ssid, &ssid_elem->data,
575 		       ssid_elem->datalen);
576 		entry->ssid_len = ssid_elem->datalen;
577 	}
578 	return 0;
579 }
580 
581 static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
582 				       struct list_head *list)
583 {
584 	struct ieee80211_neighbor_ap_info *ap_info;
585 	const struct element *elem, *ssid_elem;
586 	const u8 *pos, *end;
587 	u32 s_ssid_tmp;
588 	int n_coloc = 0, ret;
589 	LIST_HEAD(ap_list);
590 
591 	elem = cfg80211_find_elem(WLAN_EID_REDUCED_NEIGHBOR_REPORT, ies->data,
592 				  ies->len);
593 	if (!elem)
594 		return 0;
595 
596 	pos = elem->data;
597 	end = pos + elem->datalen;
598 
599 	ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp);
600 	if (ret)
601 		return ret;
602 
603 	/* RNR IE may contain more than one NEIGHBOR_AP_INFO */
604 	while (pos + sizeof(*ap_info) <= end) {
605 		enum nl80211_band band;
606 		int freq;
607 		u8 length, i, count;
608 
609 		ap_info = (void *)pos;
610 		count = u8_get_bits(ap_info->tbtt_info_hdr,
611 				    IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
612 		length = ap_info->tbtt_info_len;
613 
614 		pos += sizeof(*ap_info);
615 
616 		if (!ieee80211_operating_class_to_band(ap_info->op_class,
617 						       &band))
618 			break;
619 
620 		freq = ieee80211_channel_to_frequency(ap_info->channel, band);
621 
622 		if (end - pos < count * length)
623 			break;
624 
625 		/*
626 		 * TBTT info must include bss param + BSSID +
627 		 * (short SSID or same_ssid bit to be set).
628 		 * ignore other options, and move to the
629 		 * next AP info
630 		 */
631 		if (band != NL80211_BAND_6GHZ ||
632 		    (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&
633 		     length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {
634 			pos += count * length;
635 			continue;
636 		}
637 
638 		for (i = 0; i < count; i++) {
639 			struct cfg80211_colocated_ap *entry;
640 
641 			entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
642 					GFP_ATOMIC);
643 
644 			if (!entry)
645 				break;
646 
647 			entry->center_freq = freq;
648 
649 			if (!cfg80211_parse_ap_info(entry, pos, length,
650 						    ssid_elem, s_ssid_tmp)) {
651 				n_coloc++;
652 				list_add_tail(&entry->list, &ap_list);
653 			} else {
654 				kfree(entry);
655 			}
656 
657 			pos += length;
658 		}
659 	}
660 
661 	if (pos != end) {
662 		cfg80211_free_coloc_ap_list(&ap_list);
663 		return 0;
664 	}
665 
666 	list_splice_tail(&ap_list, list);
667 	return n_coloc;
668 }
669 
670 static  void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
671 					struct ieee80211_channel *chan,
672 					bool add_to_6ghz)
673 {
674 	int i;
675 	u32 n_channels = request->n_channels;
676 	struct cfg80211_scan_6ghz_params *params =
677 		&request->scan_6ghz_params[request->n_6ghz_params];
678 
679 	for (i = 0; i < n_channels; i++) {
680 		if (request->channels[i] == chan) {
681 			if (add_to_6ghz)
682 				params->channel_idx = i;
683 			return;
684 		}
685 	}
686 
687 	request->channels[n_channels] = chan;
688 	if (add_to_6ghz)
689 		request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
690 			n_channels;
691 
692 	request->n_channels++;
693 }
694 
695 static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
696 				     struct cfg80211_scan_request *request)
697 {
698 	int i;
699 	u32 s_ssid;
700 
701 	for (i = 0; i < request->n_ssids; i++) {
702 		/* wildcard ssid in the scan request */
703 		if (!request->ssids[i].ssid_len)
704 			return true;
705 
706 		if (ap->ssid_len &&
707 		    ap->ssid_len == request->ssids[i].ssid_len) {
708 			if (!memcmp(request->ssids[i].ssid, ap->ssid,
709 				    ap->ssid_len))
710 				return true;
711 		} else if (ap->short_ssid_valid) {
712 			s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
713 					   request->ssids[i].ssid_len);
714 
715 			if (ap->short_ssid == s_ssid)
716 				return true;
717 		}
718 	}
719 
720 	return false;
721 }
722 
723 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
724 {
725 	u8 i;
726 	struct cfg80211_colocated_ap *ap;
727 	int n_channels, count = 0, err;
728 	struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
729 	LIST_HEAD(coloc_ap_list);
730 	bool need_scan_psc = true;
731 	const struct ieee80211_sband_iftype_data *iftd;
732 
733 	rdev_req->scan_6ghz = true;
734 
735 	if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
736 		return -EOPNOTSUPP;
737 
738 	iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
739 					       rdev_req->wdev->iftype);
740 	if (!iftd || !iftd->he_cap.has_he)
741 		return -EOPNOTSUPP;
742 
743 	n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
744 
745 	if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
746 		struct cfg80211_internal_bss *intbss;
747 
748 		spin_lock_bh(&rdev->bss_lock);
749 		list_for_each_entry(intbss, &rdev->bss_list, list) {
750 			struct cfg80211_bss *res = &intbss->pub;
751 			const struct cfg80211_bss_ies *ies;
752 
753 			ies = rcu_access_pointer(res->ies);
754 			count += cfg80211_parse_colocated_ap(ies,
755 							     &coloc_ap_list);
756 		}
757 		spin_unlock_bh(&rdev->bss_lock);
758 	}
759 
760 	request = kzalloc(struct_size(request, channels, n_channels) +
761 			  sizeof(*request->scan_6ghz_params) * count +
762 			  sizeof(*request->ssids) * rdev_req->n_ssids,
763 			  GFP_KERNEL);
764 	if (!request) {
765 		cfg80211_free_coloc_ap_list(&coloc_ap_list);
766 		return -ENOMEM;
767 	}
768 
769 	*request = *rdev_req;
770 	request->n_channels = 0;
771 	request->scan_6ghz_params =
772 		(void *)&request->channels[n_channels];
773 
774 	/*
775 	 * PSC channels should not be scanned in case of direct scan with 1 SSID
776 	 * and at least one of the reported co-located APs with same SSID
777 	 * indicating that all APs in the same ESS are co-located
778 	 */
779 	if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
780 		list_for_each_entry(ap, &coloc_ap_list, list) {
781 			if (ap->colocated_ess &&
782 			    cfg80211_find_ssid_match(ap, request)) {
783 				need_scan_psc = false;
784 				break;
785 			}
786 		}
787 	}
788 
789 	/*
790 	 * add to the scan request the channels that need to be scanned
791 	 * regardless of the collocated APs (PSC channels or all channels
792 	 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
793 	 */
794 	for (i = 0; i < rdev_req->n_channels; i++) {
795 		if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
796 		    ((need_scan_psc &&
797 		      cfg80211_channel_is_psc(rdev_req->channels[i])) ||
798 		     !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
799 			cfg80211_scan_req_add_chan(request,
800 						   rdev_req->channels[i],
801 						   false);
802 		}
803 	}
804 
805 	if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
806 		goto skip;
807 
808 	list_for_each_entry(ap, &coloc_ap_list, list) {
809 		bool found = false;
810 		struct cfg80211_scan_6ghz_params *scan_6ghz_params =
811 			&request->scan_6ghz_params[request->n_6ghz_params];
812 		struct ieee80211_channel *chan =
813 			ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
814 
815 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
816 			continue;
817 
818 		for (i = 0; i < rdev_req->n_channels; i++) {
819 			if (rdev_req->channels[i] == chan)
820 				found = true;
821 		}
822 
823 		if (!found)
824 			continue;
825 
826 		if (request->n_ssids > 0 &&
827 		    !cfg80211_find_ssid_match(ap, request))
828 			continue;
829 
830 		cfg80211_scan_req_add_chan(request, chan, true);
831 		memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
832 		scan_6ghz_params->short_ssid = ap->short_ssid;
833 		scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
834 		scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
835 
836 		/*
837 		 * If a PSC channel is added to the scan and 'need_scan_psc' is
838 		 * set to false, then all the APs that the scan logic is
839 		 * interested with on the channel are collocated and thus there
840 		 * is no need to perform the initial PSC channel listen.
841 		 */
842 		if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
843 			scan_6ghz_params->psc_no_listen = true;
844 
845 		request->n_6ghz_params++;
846 	}
847 
848 skip:
849 	cfg80211_free_coloc_ap_list(&coloc_ap_list);
850 
851 	if (request->n_channels) {
852 		struct cfg80211_scan_request *old = rdev->int_scan_req;
853 		rdev->int_scan_req = request;
854 
855 		/*
856 		 * Add the ssids from the parent scan request to the new scan
857 		 * request, so the driver would be able to use them in its
858 		 * probe requests to discover hidden APs on PSC channels.
859 		 */
860 		request->ssids = (void *)&request->channels[request->n_channels];
861 		request->n_ssids = rdev_req->n_ssids;
862 		memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) *
863 		       request->n_ssids);
864 
865 		/*
866 		 * If this scan follows a previous scan, save the scan start
867 		 * info from the first part of the scan
868 		 */
869 		if (old)
870 			rdev->int_scan_req->info = old->info;
871 
872 		err = rdev_scan(rdev, request);
873 		if (err) {
874 			rdev->int_scan_req = old;
875 			kfree(request);
876 		} else {
877 			kfree(old);
878 		}
879 
880 		return err;
881 	}
882 
883 	kfree(request);
884 	return -EINVAL;
885 }
886 
887 int cfg80211_scan(struct cfg80211_registered_device *rdev)
888 {
889 	struct cfg80211_scan_request *request;
890 	struct cfg80211_scan_request *rdev_req = rdev->scan_req;
891 	u32 n_channels = 0, idx, i;
892 
893 	if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
894 		return rdev_scan(rdev, rdev_req);
895 
896 	for (i = 0; i < rdev_req->n_channels; i++) {
897 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
898 			n_channels++;
899 	}
900 
901 	if (!n_channels)
902 		return cfg80211_scan_6ghz(rdev);
903 
904 	request = kzalloc(struct_size(request, channels, n_channels),
905 			  GFP_KERNEL);
906 	if (!request)
907 		return -ENOMEM;
908 
909 	*request = *rdev_req;
910 	request->n_channels = n_channels;
911 
912 	for (i = idx = 0; i < rdev_req->n_channels; i++) {
913 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
914 			request->channels[idx++] = rdev_req->channels[i];
915 	}
916 
917 	rdev_req->scan_6ghz = false;
918 	rdev->int_scan_req = request;
919 	return rdev_scan(rdev, request);
920 }
921 
922 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
923 			   bool send_message)
924 {
925 	struct cfg80211_scan_request *request, *rdev_req;
926 	struct wireless_dev *wdev;
927 	struct sk_buff *msg;
928 #ifdef CONFIG_CFG80211_WEXT
929 	union iwreq_data wrqu;
930 #endif
931 
932 	lockdep_assert_held(&rdev->wiphy.mtx);
933 
934 	if (rdev->scan_msg) {
935 		nl80211_send_scan_msg(rdev, rdev->scan_msg);
936 		rdev->scan_msg = NULL;
937 		return;
938 	}
939 
940 	rdev_req = rdev->scan_req;
941 	if (!rdev_req)
942 		return;
943 
944 	wdev = rdev_req->wdev;
945 	request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
946 
947 	if (wdev_running(wdev) &&
948 	    (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
949 	    !rdev_req->scan_6ghz && !request->info.aborted &&
950 	    !cfg80211_scan_6ghz(rdev))
951 		return;
952 
953 	/*
954 	 * This must be before sending the other events!
955 	 * Otherwise, wpa_supplicant gets completely confused with
956 	 * wext events.
957 	 */
958 	if (wdev->netdev)
959 		cfg80211_sme_scan_done(wdev->netdev);
960 
961 	if (!request->info.aborted &&
962 	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
963 		/* flush entries from previous scans */
964 		spin_lock_bh(&rdev->bss_lock);
965 		__cfg80211_bss_expire(rdev, request->scan_start);
966 		spin_unlock_bh(&rdev->bss_lock);
967 	}
968 
969 	msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
970 
971 #ifdef CONFIG_CFG80211_WEXT
972 	if (wdev->netdev && !request->info.aborted) {
973 		memset(&wrqu, 0, sizeof(wrqu));
974 
975 		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
976 	}
977 #endif
978 
979 	dev_put(wdev->netdev);
980 
981 	kfree(rdev->int_scan_req);
982 	rdev->int_scan_req = NULL;
983 
984 	kfree(rdev->scan_req);
985 	rdev->scan_req = NULL;
986 
987 	if (!send_message)
988 		rdev->scan_msg = msg;
989 	else
990 		nl80211_send_scan_msg(rdev, msg);
991 }
992 
993 void __cfg80211_scan_done(struct work_struct *wk)
994 {
995 	struct cfg80211_registered_device *rdev;
996 
997 	rdev = container_of(wk, struct cfg80211_registered_device,
998 			    scan_done_wk);
999 
1000 	wiphy_lock(&rdev->wiphy);
1001 	___cfg80211_scan_done(rdev, true);
1002 	wiphy_unlock(&rdev->wiphy);
1003 }
1004 
1005 void cfg80211_scan_done(struct cfg80211_scan_request *request,
1006 			struct cfg80211_scan_info *info)
1007 {
1008 	struct cfg80211_scan_info old_info = request->info;
1009 
1010 	trace_cfg80211_scan_done(request, info);
1011 	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1012 		request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1013 
1014 	request->info = *info;
1015 
1016 	/*
1017 	 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1018 	 * be of the first part. In such a case old_info.scan_start_tsf should
1019 	 * be non zero.
1020 	 */
1021 	if (request->scan_6ghz && old_info.scan_start_tsf) {
1022 		request->info.scan_start_tsf = old_info.scan_start_tsf;
1023 		memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1024 		       sizeof(request->info.tsf_bssid));
1025 	}
1026 
1027 	request->notified = true;
1028 	queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1029 }
1030 EXPORT_SYMBOL(cfg80211_scan_done);
1031 
1032 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1033 				 struct cfg80211_sched_scan_request *req)
1034 {
1035 	lockdep_assert_held(&rdev->wiphy.mtx);
1036 
1037 	list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1038 }
1039 
1040 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1041 					struct cfg80211_sched_scan_request *req)
1042 {
1043 	lockdep_assert_held(&rdev->wiphy.mtx);
1044 
1045 	list_del_rcu(&req->list);
1046 	kfree_rcu(req, rcu_head);
1047 }
1048 
1049 static struct cfg80211_sched_scan_request *
1050 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1051 {
1052 	struct cfg80211_sched_scan_request *pos;
1053 
1054 	list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1055 				lockdep_is_held(&rdev->wiphy.mtx)) {
1056 		if (pos->reqid == reqid)
1057 			return pos;
1058 	}
1059 	return NULL;
1060 }
1061 
1062 /*
1063  * Determines if a scheduled scan request can be handled. When a legacy
1064  * scheduled scan is running no other scheduled scan is allowed regardless
1065  * whether the request is for legacy or multi-support scan. When a multi-support
1066  * scheduled scan is running a request for legacy scan is not allowed. In this
1067  * case a request for multi-support scan can be handled if resources are
1068  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1069  */
1070 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1071 				     bool want_multi)
1072 {
1073 	struct cfg80211_sched_scan_request *pos;
1074 	int i = 0;
1075 
1076 	list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1077 		/* request id zero means legacy in progress */
1078 		if (!i && !pos->reqid)
1079 			return -EINPROGRESS;
1080 		i++;
1081 	}
1082 
1083 	if (i) {
1084 		/* no legacy allowed when multi request(s) are active */
1085 		if (!want_multi)
1086 			return -EINPROGRESS;
1087 
1088 		/* resource limit reached */
1089 		if (i == rdev->wiphy.max_sched_scan_reqs)
1090 			return -ENOSPC;
1091 	}
1092 	return 0;
1093 }
1094 
1095 void cfg80211_sched_scan_results_wk(struct work_struct *work)
1096 {
1097 	struct cfg80211_registered_device *rdev;
1098 	struct cfg80211_sched_scan_request *req, *tmp;
1099 
1100 	rdev = container_of(work, struct cfg80211_registered_device,
1101 			   sched_scan_res_wk);
1102 
1103 	wiphy_lock(&rdev->wiphy);
1104 	list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1105 		if (req->report_results) {
1106 			req->report_results = false;
1107 			if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1108 				/* flush entries from previous scans */
1109 				spin_lock_bh(&rdev->bss_lock);
1110 				__cfg80211_bss_expire(rdev, req->scan_start);
1111 				spin_unlock_bh(&rdev->bss_lock);
1112 				req->scan_start = jiffies;
1113 			}
1114 			nl80211_send_sched_scan(req,
1115 						NL80211_CMD_SCHED_SCAN_RESULTS);
1116 		}
1117 	}
1118 	wiphy_unlock(&rdev->wiphy);
1119 }
1120 
1121 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1122 {
1123 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1124 	struct cfg80211_sched_scan_request *request;
1125 
1126 	trace_cfg80211_sched_scan_results(wiphy, reqid);
1127 	/* ignore if we're not scanning */
1128 
1129 	rcu_read_lock();
1130 	request = cfg80211_find_sched_scan_req(rdev, reqid);
1131 	if (request) {
1132 		request->report_results = true;
1133 		queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1134 	}
1135 	rcu_read_unlock();
1136 }
1137 EXPORT_SYMBOL(cfg80211_sched_scan_results);
1138 
1139 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1140 {
1141 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1142 
1143 	lockdep_assert_held(&wiphy->mtx);
1144 
1145 	trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1146 
1147 	__cfg80211_stop_sched_scan(rdev, reqid, true);
1148 }
1149 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1150 
1151 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1152 {
1153 	wiphy_lock(wiphy);
1154 	cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1155 	wiphy_unlock(wiphy);
1156 }
1157 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1158 
1159 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1160 				 struct cfg80211_sched_scan_request *req,
1161 				 bool driver_initiated)
1162 {
1163 	lockdep_assert_held(&rdev->wiphy.mtx);
1164 
1165 	if (!driver_initiated) {
1166 		int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1167 		if (err)
1168 			return err;
1169 	}
1170 
1171 	nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1172 
1173 	cfg80211_del_sched_scan_req(rdev, req);
1174 
1175 	return 0;
1176 }
1177 
1178 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1179 			       u64 reqid, bool driver_initiated)
1180 {
1181 	struct cfg80211_sched_scan_request *sched_scan_req;
1182 
1183 	lockdep_assert_held(&rdev->wiphy.mtx);
1184 
1185 	sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1186 	if (!sched_scan_req)
1187 		return -ENOENT;
1188 
1189 	return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1190 					    driver_initiated);
1191 }
1192 
1193 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1194                       unsigned long age_secs)
1195 {
1196 	struct cfg80211_internal_bss *bss;
1197 	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1198 
1199 	spin_lock_bh(&rdev->bss_lock);
1200 	list_for_each_entry(bss, &rdev->bss_list, list)
1201 		bss->ts -= age_jiffies;
1202 	spin_unlock_bh(&rdev->bss_lock);
1203 }
1204 
1205 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1206 {
1207 	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1208 }
1209 
1210 void cfg80211_bss_flush(struct wiphy *wiphy)
1211 {
1212 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1213 
1214 	spin_lock_bh(&rdev->bss_lock);
1215 	__cfg80211_bss_expire(rdev, jiffies);
1216 	spin_unlock_bh(&rdev->bss_lock);
1217 }
1218 EXPORT_SYMBOL(cfg80211_bss_flush);
1219 
1220 const struct element *
1221 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1222 			 const u8 *match, unsigned int match_len,
1223 			 unsigned int match_offset)
1224 {
1225 	const struct element *elem;
1226 
1227 	for_each_element_id(elem, eid, ies, len) {
1228 		if (elem->datalen >= match_offset + match_len &&
1229 		    !memcmp(elem->data + match_offset, match, match_len))
1230 			return elem;
1231 	}
1232 
1233 	return NULL;
1234 }
1235 EXPORT_SYMBOL(cfg80211_find_elem_match);
1236 
1237 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1238 						const u8 *ies,
1239 						unsigned int len)
1240 {
1241 	const struct element *elem;
1242 	u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1243 	int match_len = (oui_type < 0) ? 3 : sizeof(match);
1244 
1245 	if (WARN_ON(oui_type > 0xff))
1246 		return NULL;
1247 
1248 	elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1249 					match, match_len, 0);
1250 
1251 	if (!elem || elem->datalen < 4)
1252 		return NULL;
1253 
1254 	return elem;
1255 }
1256 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1257 
1258 /**
1259  * enum bss_compare_mode - BSS compare mode
1260  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1261  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1262  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1263  */
1264 enum bss_compare_mode {
1265 	BSS_CMP_REGULAR,
1266 	BSS_CMP_HIDE_ZLEN,
1267 	BSS_CMP_HIDE_NUL,
1268 };
1269 
1270 static int cmp_bss(struct cfg80211_bss *a,
1271 		   struct cfg80211_bss *b,
1272 		   enum bss_compare_mode mode)
1273 {
1274 	const struct cfg80211_bss_ies *a_ies, *b_ies;
1275 	const u8 *ie1 = NULL;
1276 	const u8 *ie2 = NULL;
1277 	int i, r;
1278 
1279 	if (a->channel != b->channel)
1280 		return b->channel->center_freq - a->channel->center_freq;
1281 
1282 	a_ies = rcu_access_pointer(a->ies);
1283 	if (!a_ies)
1284 		return -1;
1285 	b_ies = rcu_access_pointer(b->ies);
1286 	if (!b_ies)
1287 		return 1;
1288 
1289 	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1290 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1291 				       a_ies->data, a_ies->len);
1292 	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1293 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1294 				       b_ies->data, b_ies->len);
1295 	if (ie1 && ie2) {
1296 		int mesh_id_cmp;
1297 
1298 		if (ie1[1] == ie2[1])
1299 			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1300 		else
1301 			mesh_id_cmp = ie2[1] - ie1[1];
1302 
1303 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1304 				       a_ies->data, a_ies->len);
1305 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1306 				       b_ies->data, b_ies->len);
1307 		if (ie1 && ie2) {
1308 			if (mesh_id_cmp)
1309 				return mesh_id_cmp;
1310 			if (ie1[1] != ie2[1])
1311 				return ie2[1] - ie1[1];
1312 			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1313 		}
1314 	}
1315 
1316 	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1317 	if (r)
1318 		return r;
1319 
1320 	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1321 	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1322 
1323 	if (!ie1 && !ie2)
1324 		return 0;
1325 
1326 	/*
1327 	 * Note that with "hide_ssid", the function returns a match if
1328 	 * the already-present BSS ("b") is a hidden SSID beacon for
1329 	 * the new BSS ("a").
1330 	 */
1331 
1332 	/* sort missing IE before (left of) present IE */
1333 	if (!ie1)
1334 		return -1;
1335 	if (!ie2)
1336 		return 1;
1337 
1338 	switch (mode) {
1339 	case BSS_CMP_HIDE_ZLEN:
1340 		/*
1341 		 * In ZLEN mode we assume the BSS entry we're
1342 		 * looking for has a zero-length SSID. So if
1343 		 * the one we're looking at right now has that,
1344 		 * return 0. Otherwise, return the difference
1345 		 * in length, but since we're looking for the
1346 		 * 0-length it's really equivalent to returning
1347 		 * the length of the one we're looking at.
1348 		 *
1349 		 * No content comparison is needed as we assume
1350 		 * the content length is zero.
1351 		 */
1352 		return ie2[1];
1353 	case BSS_CMP_REGULAR:
1354 	default:
1355 		/* sort by length first, then by contents */
1356 		if (ie1[1] != ie2[1])
1357 			return ie2[1] - ie1[1];
1358 		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1359 	case BSS_CMP_HIDE_NUL:
1360 		if (ie1[1] != ie2[1])
1361 			return ie2[1] - ie1[1];
1362 		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1363 		for (i = 0; i < ie2[1]; i++)
1364 			if (ie2[i + 2])
1365 				return -1;
1366 		return 0;
1367 	}
1368 }
1369 
1370 static bool cfg80211_bss_type_match(u16 capability,
1371 				    enum nl80211_band band,
1372 				    enum ieee80211_bss_type bss_type)
1373 {
1374 	bool ret = true;
1375 	u16 mask, val;
1376 
1377 	if (bss_type == IEEE80211_BSS_TYPE_ANY)
1378 		return ret;
1379 
1380 	if (band == NL80211_BAND_60GHZ) {
1381 		mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1382 		switch (bss_type) {
1383 		case IEEE80211_BSS_TYPE_ESS:
1384 			val = WLAN_CAPABILITY_DMG_TYPE_AP;
1385 			break;
1386 		case IEEE80211_BSS_TYPE_PBSS:
1387 			val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1388 			break;
1389 		case IEEE80211_BSS_TYPE_IBSS:
1390 			val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1391 			break;
1392 		default:
1393 			return false;
1394 		}
1395 	} else {
1396 		mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1397 		switch (bss_type) {
1398 		case IEEE80211_BSS_TYPE_ESS:
1399 			val = WLAN_CAPABILITY_ESS;
1400 			break;
1401 		case IEEE80211_BSS_TYPE_IBSS:
1402 			val = WLAN_CAPABILITY_IBSS;
1403 			break;
1404 		case IEEE80211_BSS_TYPE_MBSS:
1405 			val = 0;
1406 			break;
1407 		default:
1408 			return false;
1409 		}
1410 	}
1411 
1412 	ret = ((capability & mask) == val);
1413 	return ret;
1414 }
1415 
1416 /* Returned bss is reference counted and must be cleaned up appropriately. */
1417 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1418 				      struct ieee80211_channel *channel,
1419 				      const u8 *bssid,
1420 				      const u8 *ssid, size_t ssid_len,
1421 				      enum ieee80211_bss_type bss_type,
1422 				      enum ieee80211_privacy privacy)
1423 {
1424 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1425 	struct cfg80211_internal_bss *bss, *res = NULL;
1426 	unsigned long now = jiffies;
1427 	int bss_privacy;
1428 
1429 	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1430 			       privacy);
1431 
1432 	spin_lock_bh(&rdev->bss_lock);
1433 
1434 	list_for_each_entry(bss, &rdev->bss_list, list) {
1435 		if (!cfg80211_bss_type_match(bss->pub.capability,
1436 					     bss->pub.channel->band, bss_type))
1437 			continue;
1438 
1439 		bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1440 		if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1441 		    (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1442 			continue;
1443 		if (channel && bss->pub.channel != channel)
1444 			continue;
1445 		if (!is_valid_ether_addr(bss->pub.bssid))
1446 			continue;
1447 		/* Don't get expired BSS structs */
1448 		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1449 		    !atomic_read(&bss->hold))
1450 			continue;
1451 		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1452 			res = bss;
1453 			bss_ref_get(rdev, res);
1454 			break;
1455 		}
1456 	}
1457 
1458 	spin_unlock_bh(&rdev->bss_lock);
1459 	if (!res)
1460 		return NULL;
1461 	trace_cfg80211_return_bss(&res->pub);
1462 	return &res->pub;
1463 }
1464 EXPORT_SYMBOL(cfg80211_get_bss);
1465 
1466 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1467 			  struct cfg80211_internal_bss *bss)
1468 {
1469 	struct rb_node **p = &rdev->bss_tree.rb_node;
1470 	struct rb_node *parent = NULL;
1471 	struct cfg80211_internal_bss *tbss;
1472 	int cmp;
1473 
1474 	while (*p) {
1475 		parent = *p;
1476 		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1477 
1478 		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1479 
1480 		if (WARN_ON(!cmp)) {
1481 			/* will sort of leak this BSS */
1482 			return;
1483 		}
1484 
1485 		if (cmp < 0)
1486 			p = &(*p)->rb_left;
1487 		else
1488 			p = &(*p)->rb_right;
1489 	}
1490 
1491 	rb_link_node(&bss->rbn, parent, p);
1492 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
1493 }
1494 
1495 static struct cfg80211_internal_bss *
1496 rb_find_bss(struct cfg80211_registered_device *rdev,
1497 	    struct cfg80211_internal_bss *res,
1498 	    enum bss_compare_mode mode)
1499 {
1500 	struct rb_node *n = rdev->bss_tree.rb_node;
1501 	struct cfg80211_internal_bss *bss;
1502 	int r;
1503 
1504 	while (n) {
1505 		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1506 		r = cmp_bss(&res->pub, &bss->pub, mode);
1507 
1508 		if (r == 0)
1509 			return bss;
1510 		else if (r < 0)
1511 			n = n->rb_left;
1512 		else
1513 			n = n->rb_right;
1514 	}
1515 
1516 	return NULL;
1517 }
1518 
1519 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1520 				   struct cfg80211_internal_bss *new)
1521 {
1522 	const struct cfg80211_bss_ies *ies;
1523 	struct cfg80211_internal_bss *bss;
1524 	const u8 *ie;
1525 	int i, ssidlen;
1526 	u8 fold = 0;
1527 	u32 n_entries = 0;
1528 
1529 	ies = rcu_access_pointer(new->pub.beacon_ies);
1530 	if (WARN_ON(!ies))
1531 		return false;
1532 
1533 	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1534 	if (!ie) {
1535 		/* nothing to do */
1536 		return true;
1537 	}
1538 
1539 	ssidlen = ie[1];
1540 	for (i = 0; i < ssidlen; i++)
1541 		fold |= ie[2 + i];
1542 
1543 	if (fold) {
1544 		/* not a hidden SSID */
1545 		return true;
1546 	}
1547 
1548 	/* This is the bad part ... */
1549 
1550 	list_for_each_entry(bss, &rdev->bss_list, list) {
1551 		/*
1552 		 * we're iterating all the entries anyway, so take the
1553 		 * opportunity to validate the list length accounting
1554 		 */
1555 		n_entries++;
1556 
1557 		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1558 			continue;
1559 		if (bss->pub.channel != new->pub.channel)
1560 			continue;
1561 		if (bss->pub.scan_width != new->pub.scan_width)
1562 			continue;
1563 		if (rcu_access_pointer(bss->pub.beacon_ies))
1564 			continue;
1565 		ies = rcu_access_pointer(bss->pub.ies);
1566 		if (!ies)
1567 			continue;
1568 		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1569 		if (!ie)
1570 			continue;
1571 		if (ssidlen && ie[1] != ssidlen)
1572 			continue;
1573 		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1574 			continue;
1575 		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1576 			list_del(&bss->hidden_list);
1577 		/* combine them */
1578 		list_add(&bss->hidden_list, &new->hidden_list);
1579 		bss->pub.hidden_beacon_bss = &new->pub;
1580 		new->refcount += bss->refcount;
1581 		rcu_assign_pointer(bss->pub.beacon_ies,
1582 				   new->pub.beacon_ies);
1583 	}
1584 
1585 	WARN_ONCE(n_entries != rdev->bss_entries,
1586 		  "rdev bss entries[%d]/list[len:%d] corruption\n",
1587 		  rdev->bss_entries, n_entries);
1588 
1589 	return true;
1590 }
1591 
1592 struct cfg80211_non_tx_bss {
1593 	struct cfg80211_bss *tx_bss;
1594 	u8 max_bssid_indicator;
1595 	u8 bssid_index;
1596 };
1597 
1598 static bool
1599 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1600 			  struct cfg80211_internal_bss *known,
1601 			  struct cfg80211_internal_bss *new,
1602 			  bool signal_valid)
1603 {
1604 	lockdep_assert_held(&rdev->bss_lock);
1605 
1606 	/* Update IEs */
1607 	if (rcu_access_pointer(new->pub.proberesp_ies)) {
1608 		const struct cfg80211_bss_ies *old;
1609 
1610 		old = rcu_access_pointer(known->pub.proberesp_ies);
1611 
1612 		rcu_assign_pointer(known->pub.proberesp_ies,
1613 				   new->pub.proberesp_ies);
1614 		/* Override possible earlier Beacon frame IEs */
1615 		rcu_assign_pointer(known->pub.ies,
1616 				   new->pub.proberesp_ies);
1617 		if (old)
1618 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1619 	} else if (rcu_access_pointer(new->pub.beacon_ies)) {
1620 		const struct cfg80211_bss_ies *old;
1621 		struct cfg80211_internal_bss *bss;
1622 
1623 		if (known->pub.hidden_beacon_bss &&
1624 		    !list_empty(&known->hidden_list)) {
1625 			const struct cfg80211_bss_ies *f;
1626 
1627 			/* The known BSS struct is one of the probe
1628 			 * response members of a group, but we're
1629 			 * receiving a beacon (beacon_ies in the new
1630 			 * bss is used). This can only mean that the
1631 			 * AP changed its beacon from not having an
1632 			 * SSID to showing it, which is confusing so
1633 			 * drop this information.
1634 			 */
1635 
1636 			f = rcu_access_pointer(new->pub.beacon_ies);
1637 			kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1638 			return false;
1639 		}
1640 
1641 		old = rcu_access_pointer(known->pub.beacon_ies);
1642 
1643 		rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1644 
1645 		/* Override IEs if they were from a beacon before */
1646 		if (old == rcu_access_pointer(known->pub.ies))
1647 			rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1648 
1649 		/* Assign beacon IEs to all sub entries */
1650 		list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1651 			const struct cfg80211_bss_ies *ies;
1652 
1653 			ies = rcu_access_pointer(bss->pub.beacon_ies);
1654 			WARN_ON(ies != old);
1655 
1656 			rcu_assign_pointer(bss->pub.beacon_ies,
1657 					   new->pub.beacon_ies);
1658 		}
1659 
1660 		if (old)
1661 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1662 	}
1663 
1664 	known->pub.beacon_interval = new->pub.beacon_interval;
1665 
1666 	/* don't update the signal if beacon was heard on
1667 	 * adjacent channel.
1668 	 */
1669 	if (signal_valid)
1670 		known->pub.signal = new->pub.signal;
1671 	known->pub.capability = new->pub.capability;
1672 	known->ts = new->ts;
1673 	known->ts_boottime = new->ts_boottime;
1674 	known->parent_tsf = new->parent_tsf;
1675 	known->pub.chains = new->pub.chains;
1676 	memcpy(known->pub.chain_signal, new->pub.chain_signal,
1677 	       IEEE80211_MAX_CHAINS);
1678 	ether_addr_copy(known->parent_bssid, new->parent_bssid);
1679 	known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1680 	known->pub.bssid_index = new->pub.bssid_index;
1681 
1682 	return true;
1683 }
1684 
1685 /* Returned bss is reference counted and must be cleaned up appropriately. */
1686 struct cfg80211_internal_bss *
1687 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1688 		    struct cfg80211_internal_bss *tmp,
1689 		    bool signal_valid, unsigned long ts)
1690 {
1691 	struct cfg80211_internal_bss *found = NULL;
1692 
1693 	if (WARN_ON(!tmp->pub.channel))
1694 		return NULL;
1695 
1696 	tmp->ts = ts;
1697 
1698 	spin_lock_bh(&rdev->bss_lock);
1699 
1700 	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1701 		spin_unlock_bh(&rdev->bss_lock);
1702 		return NULL;
1703 	}
1704 
1705 	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1706 
1707 	if (found) {
1708 		if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1709 			goto drop;
1710 	} else {
1711 		struct cfg80211_internal_bss *new;
1712 		struct cfg80211_internal_bss *hidden;
1713 		struct cfg80211_bss_ies *ies;
1714 
1715 		/*
1716 		 * create a copy -- the "res" variable that is passed in
1717 		 * is allocated on the stack since it's not needed in the
1718 		 * more common case of an update
1719 		 */
1720 		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1721 			      GFP_ATOMIC);
1722 		if (!new) {
1723 			ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1724 			if (ies)
1725 				kfree_rcu(ies, rcu_head);
1726 			ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1727 			if (ies)
1728 				kfree_rcu(ies, rcu_head);
1729 			goto drop;
1730 		}
1731 		memcpy(new, tmp, sizeof(*new));
1732 		new->refcount = 1;
1733 		INIT_LIST_HEAD(&new->hidden_list);
1734 		INIT_LIST_HEAD(&new->pub.nontrans_list);
1735 
1736 		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1737 			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1738 			if (!hidden)
1739 				hidden = rb_find_bss(rdev, tmp,
1740 						     BSS_CMP_HIDE_NUL);
1741 			if (hidden) {
1742 				new->pub.hidden_beacon_bss = &hidden->pub;
1743 				list_add(&new->hidden_list,
1744 					 &hidden->hidden_list);
1745 				hidden->refcount++;
1746 				rcu_assign_pointer(new->pub.beacon_ies,
1747 						   hidden->pub.beacon_ies);
1748 			}
1749 		} else {
1750 			/*
1751 			 * Ok so we found a beacon, and don't have an entry. If
1752 			 * it's a beacon with hidden SSID, we might be in for an
1753 			 * expensive search for any probe responses that should
1754 			 * be grouped with this beacon for updates ...
1755 			 */
1756 			if (!cfg80211_combine_bsses(rdev, new)) {
1757 				bss_ref_put(rdev, new);
1758 				goto drop;
1759 			}
1760 		}
1761 
1762 		if (rdev->bss_entries >= bss_entries_limit &&
1763 		    !cfg80211_bss_expire_oldest(rdev)) {
1764 			bss_ref_put(rdev, new);
1765 			goto drop;
1766 		}
1767 
1768 		/* This must be before the call to bss_ref_get */
1769 		if (tmp->pub.transmitted_bss) {
1770 			struct cfg80211_internal_bss *pbss =
1771 				container_of(tmp->pub.transmitted_bss,
1772 					     struct cfg80211_internal_bss,
1773 					     pub);
1774 
1775 			new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1776 			bss_ref_get(rdev, pbss);
1777 		}
1778 
1779 		list_add_tail(&new->list, &rdev->bss_list);
1780 		rdev->bss_entries++;
1781 		rb_insert_bss(rdev, new);
1782 		found = new;
1783 	}
1784 
1785 	rdev->bss_generation++;
1786 	bss_ref_get(rdev, found);
1787 	spin_unlock_bh(&rdev->bss_lock);
1788 
1789 	return found;
1790  drop:
1791 	spin_unlock_bh(&rdev->bss_lock);
1792 	return NULL;
1793 }
1794 
1795 int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen,
1796 				    enum nl80211_band band,
1797 				    enum cfg80211_bss_frame_type ftype)
1798 {
1799 	const struct element *tmp;
1800 
1801 	if (band == NL80211_BAND_6GHZ) {
1802 		struct ieee80211_he_operation *he_oper;
1803 
1804 		tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie,
1805 					     ielen);
1806 		if (tmp && tmp->datalen >= sizeof(*he_oper) &&
1807 		    tmp->datalen >= ieee80211_he_oper_size(&tmp->data[1])) {
1808 			const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
1809 
1810 			he_oper = (void *)&tmp->data[1];
1811 
1812 			he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
1813 			if (!he_6ghz_oper)
1814 				return -1;
1815 
1816 			if (ftype != CFG80211_BSS_FTYPE_BEACON ||
1817 			    he_6ghz_oper->control & IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)
1818 				return he_6ghz_oper->primary;
1819 		}
1820 	} else if (band == NL80211_BAND_S1GHZ) {
1821 		tmp = cfg80211_find_elem(WLAN_EID_S1G_OPERATION, ie, ielen);
1822 		if (tmp && tmp->datalen >= sizeof(struct ieee80211_s1g_oper_ie)) {
1823 			struct ieee80211_s1g_oper_ie *s1gop = (void *)tmp->data;
1824 
1825 			return s1gop->primary_ch;
1826 		}
1827 	} else {
1828 		tmp = cfg80211_find_elem(WLAN_EID_DS_PARAMS, ie, ielen);
1829 		if (tmp && tmp->datalen == 1)
1830 			return tmp->data[0];
1831 
1832 		tmp = cfg80211_find_elem(WLAN_EID_HT_OPERATION, ie, ielen);
1833 		if (tmp &&
1834 		    tmp->datalen >= sizeof(struct ieee80211_ht_operation)) {
1835 			struct ieee80211_ht_operation *htop = (void *)tmp->data;
1836 
1837 			return htop->primary_chan;
1838 		}
1839 	}
1840 
1841 	return -1;
1842 }
1843 EXPORT_SYMBOL(cfg80211_get_ies_channel_number);
1844 
1845 /*
1846  * Update RX channel information based on the available frame payload
1847  * information. This is mainly for the 2.4 GHz band where frames can be received
1848  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1849  * element to indicate the current (transmitting) channel, but this might also
1850  * be needed on other bands if RX frequency does not match with the actual
1851  * operating channel of a BSS, or if the AP reports a different primary channel.
1852  */
1853 static struct ieee80211_channel *
1854 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1855 			 struct ieee80211_channel *channel,
1856 			 enum nl80211_bss_scan_width scan_width,
1857 			 enum cfg80211_bss_frame_type ftype)
1858 {
1859 	u32 freq;
1860 	int channel_number;
1861 	struct ieee80211_channel *alt_channel;
1862 
1863 	channel_number = cfg80211_get_ies_channel_number(ie, ielen,
1864 							 channel->band, ftype);
1865 
1866 	if (channel_number < 0) {
1867 		/* No channel information in frame payload */
1868 		return channel;
1869 	}
1870 
1871 	freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1872 
1873 	/*
1874 	 * In 6GHz, duplicated beacon indication is relevant for
1875 	 * beacons only.
1876 	 */
1877 	if (channel->band == NL80211_BAND_6GHZ &&
1878 	    (freq == channel->center_freq ||
1879 	     abs(freq - channel->center_freq) > 80))
1880 		return channel;
1881 
1882 	alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1883 	if (!alt_channel) {
1884 		if (channel->band == NL80211_BAND_2GHZ) {
1885 			/*
1886 			 * Better not allow unexpected channels when that could
1887 			 * be going beyond the 1-11 range (e.g., discovering
1888 			 * BSS on channel 12 when radio is configured for
1889 			 * channel 11.
1890 			 */
1891 			return NULL;
1892 		}
1893 
1894 		/* No match for the payload channel number - ignore it */
1895 		return channel;
1896 	}
1897 
1898 	if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1899 	    scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1900 		/*
1901 		 * Ignore channel number in 5 and 10 MHz channels where there
1902 		 * may not be an n:1 or 1:n mapping between frequencies and
1903 		 * channel numbers.
1904 		 */
1905 		return channel;
1906 	}
1907 
1908 	/*
1909 	 * Use the channel determined through the payload channel number
1910 	 * instead of the RX channel reported by the driver.
1911 	 */
1912 	if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1913 		return NULL;
1914 	return alt_channel;
1915 }
1916 
1917 /* Returned bss is reference counted and must be cleaned up appropriately. */
1918 static struct cfg80211_bss *
1919 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1920 				struct cfg80211_inform_bss *data,
1921 				enum cfg80211_bss_frame_type ftype,
1922 				const u8 *bssid, u64 tsf, u16 capability,
1923 				u16 beacon_interval, const u8 *ie, size_t ielen,
1924 				struct cfg80211_non_tx_bss *non_tx_data,
1925 				gfp_t gfp)
1926 {
1927 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1928 	struct cfg80211_bss_ies *ies;
1929 	struct ieee80211_channel *channel;
1930 	struct cfg80211_internal_bss tmp = {}, *res;
1931 	int bss_type;
1932 	bool signal_valid;
1933 	unsigned long ts;
1934 
1935 	if (WARN_ON(!wiphy))
1936 		return NULL;
1937 
1938 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1939 		    (data->signal < 0 || data->signal > 100)))
1940 		return NULL;
1941 
1942 	channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1943 					   data->scan_width, ftype);
1944 	if (!channel)
1945 		return NULL;
1946 
1947 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1948 	tmp.pub.channel = channel;
1949 	tmp.pub.scan_width = data->scan_width;
1950 	tmp.pub.signal = data->signal;
1951 	tmp.pub.beacon_interval = beacon_interval;
1952 	tmp.pub.capability = capability;
1953 	tmp.ts_boottime = data->boottime_ns;
1954 	tmp.parent_tsf = data->parent_tsf;
1955 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1956 
1957 	if (non_tx_data) {
1958 		tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1959 		ts = bss_from_pub(non_tx_data->tx_bss)->ts;
1960 		tmp.pub.bssid_index = non_tx_data->bssid_index;
1961 		tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1962 	} else {
1963 		ts = jiffies;
1964 	}
1965 
1966 	/*
1967 	 * If we do not know here whether the IEs are from a Beacon or Probe
1968 	 * Response frame, we need to pick one of the options and only use it
1969 	 * with the driver that does not provide the full Beacon/Probe Response
1970 	 * frame. Use Beacon frame pointer to avoid indicating that this should
1971 	 * override the IEs pointer should we have received an earlier
1972 	 * indication of Probe Response data.
1973 	 */
1974 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
1975 	if (!ies)
1976 		return NULL;
1977 	ies->len = ielen;
1978 	ies->tsf = tsf;
1979 	ies->from_beacon = false;
1980 	memcpy(ies->data, ie, ielen);
1981 
1982 	switch (ftype) {
1983 	case CFG80211_BSS_FTYPE_BEACON:
1984 		ies->from_beacon = true;
1985 		fallthrough;
1986 	case CFG80211_BSS_FTYPE_UNKNOWN:
1987 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1988 		break;
1989 	case CFG80211_BSS_FTYPE_PRESP:
1990 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1991 		break;
1992 	}
1993 	rcu_assign_pointer(tmp.pub.ies, ies);
1994 
1995 	signal_valid = data->chan == channel;
1996 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
1997 	if (!res)
1998 		return NULL;
1999 
2000 	if (channel->band == NL80211_BAND_60GHZ) {
2001 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2002 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2003 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2004 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2005 	} else {
2006 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
2007 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2008 	}
2009 
2010 	if (non_tx_data) {
2011 		/* this is a nontransmitting bss, we need to add it to
2012 		 * transmitting bss' list if it is not there
2013 		 */
2014 		if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
2015 					       &res->pub)) {
2016 			if (__cfg80211_unlink_bss(rdev, res))
2017 				rdev->bss_generation++;
2018 		}
2019 	}
2020 
2021 	trace_cfg80211_return_bss(&res->pub);
2022 	/* cfg80211_bss_update gives us a referenced result */
2023 	return &res->pub;
2024 }
2025 
2026 static const struct element
2027 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
2028 				   const struct element *mbssid_elem,
2029 				   const struct element *sub_elem)
2030 {
2031 	const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
2032 	const struct element *next_mbssid;
2033 	const struct element *next_sub;
2034 
2035 	next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2036 					 mbssid_end,
2037 					 ielen - (mbssid_end - ie));
2038 
2039 	/*
2040 	 * If it is not the last subelement in current MBSSID IE or there isn't
2041 	 * a next MBSSID IE - profile is complete.
2042 	*/
2043 	if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2044 	    !next_mbssid)
2045 		return NULL;
2046 
2047 	/* For any length error, just return NULL */
2048 
2049 	if (next_mbssid->datalen < 4)
2050 		return NULL;
2051 
2052 	next_sub = (void *)&next_mbssid->data[1];
2053 
2054 	if (next_mbssid->data + next_mbssid->datalen <
2055 	    next_sub->data + next_sub->datalen)
2056 		return NULL;
2057 
2058 	if (next_sub->id != 0 || next_sub->datalen < 2)
2059 		return NULL;
2060 
2061 	/*
2062 	 * Check if the first element in the next sub element is a start
2063 	 * of a new profile
2064 	 */
2065 	return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2066 	       NULL : next_mbssid;
2067 }
2068 
2069 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2070 			      const struct element *mbssid_elem,
2071 			      const struct element *sub_elem,
2072 			      u8 *merged_ie, size_t max_copy_len)
2073 {
2074 	size_t copied_len = sub_elem->datalen;
2075 	const struct element *next_mbssid;
2076 
2077 	if (sub_elem->datalen > max_copy_len)
2078 		return 0;
2079 
2080 	memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2081 
2082 	while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2083 								mbssid_elem,
2084 								sub_elem))) {
2085 		const struct element *next_sub = (void *)&next_mbssid->data[1];
2086 
2087 		if (copied_len + next_sub->datalen > max_copy_len)
2088 			break;
2089 		memcpy(merged_ie + copied_len, next_sub->data,
2090 		       next_sub->datalen);
2091 		copied_len += next_sub->datalen;
2092 	}
2093 
2094 	return copied_len;
2095 }
2096 EXPORT_SYMBOL(cfg80211_merge_profile);
2097 
2098 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2099 				       struct cfg80211_inform_bss *data,
2100 				       enum cfg80211_bss_frame_type ftype,
2101 				       const u8 *bssid, u64 tsf,
2102 				       u16 beacon_interval, const u8 *ie,
2103 				       size_t ielen,
2104 				       struct cfg80211_non_tx_bss *non_tx_data,
2105 				       gfp_t gfp)
2106 {
2107 	const u8 *mbssid_index_ie;
2108 	const struct element *elem, *sub;
2109 	size_t new_ie_len;
2110 	u8 new_bssid[ETH_ALEN];
2111 	u8 *new_ie, *profile;
2112 	u64 seen_indices = 0;
2113 	u16 capability;
2114 	struct cfg80211_bss *bss;
2115 
2116 	if (!non_tx_data)
2117 		return;
2118 	if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2119 		return;
2120 	if (!wiphy->support_mbssid)
2121 		return;
2122 	if (wiphy->support_only_he_mbssid &&
2123 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2124 		return;
2125 
2126 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2127 	if (!new_ie)
2128 		return;
2129 
2130 	profile = kmalloc(ielen, gfp);
2131 	if (!profile)
2132 		goto out;
2133 
2134 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
2135 		if (elem->datalen < 4)
2136 			continue;
2137 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2138 			u8 profile_len;
2139 
2140 			if (sub->id != 0 || sub->datalen < 4) {
2141 				/* not a valid BSS profile */
2142 				continue;
2143 			}
2144 
2145 			if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2146 			    sub->data[1] != 2) {
2147 				/* The first element within the Nontransmitted
2148 				 * BSSID Profile is not the Nontransmitted
2149 				 * BSSID Capability element.
2150 				 */
2151 				continue;
2152 			}
2153 
2154 			memset(profile, 0, ielen);
2155 			profile_len = cfg80211_merge_profile(ie, ielen,
2156 							     elem,
2157 							     sub,
2158 							     profile,
2159 							     ielen);
2160 
2161 			/* found a Nontransmitted BSSID Profile */
2162 			mbssid_index_ie = cfg80211_find_ie
2163 				(WLAN_EID_MULTI_BSSID_IDX,
2164 				 profile, profile_len);
2165 			if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2166 			    mbssid_index_ie[2] == 0 ||
2167 			    mbssid_index_ie[2] > 46) {
2168 				/* No valid Multiple BSSID-Index element */
2169 				continue;
2170 			}
2171 
2172 			if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2173 				/* We don't support legacy split of a profile */
2174 				net_dbg_ratelimited("Partial info for BSSID index %d\n",
2175 						    mbssid_index_ie[2]);
2176 
2177 			seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2178 
2179 			non_tx_data->bssid_index = mbssid_index_ie[2];
2180 			non_tx_data->max_bssid_indicator = elem->data[0];
2181 
2182 			cfg80211_gen_new_bssid(bssid,
2183 					       non_tx_data->max_bssid_indicator,
2184 					       non_tx_data->bssid_index,
2185 					       new_bssid);
2186 			memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2187 			new_ie_len = cfg80211_gen_new_ie(ie, ielen,
2188 							 profile,
2189 							 profile_len, new_ie,
2190 							 gfp);
2191 			if (!new_ie_len)
2192 				continue;
2193 
2194 			capability = get_unaligned_le16(profile + 2);
2195 			bss = cfg80211_inform_single_bss_data(wiphy, data,
2196 							      ftype,
2197 							      new_bssid, tsf,
2198 							      capability,
2199 							      beacon_interval,
2200 							      new_ie,
2201 							      new_ie_len,
2202 							      non_tx_data,
2203 							      gfp);
2204 			if (!bss)
2205 				break;
2206 			cfg80211_put_bss(wiphy, bss);
2207 		}
2208 	}
2209 
2210 out:
2211 	kfree(new_ie);
2212 	kfree(profile);
2213 }
2214 
2215 struct cfg80211_bss *
2216 cfg80211_inform_bss_data(struct wiphy *wiphy,
2217 			 struct cfg80211_inform_bss *data,
2218 			 enum cfg80211_bss_frame_type ftype,
2219 			 const u8 *bssid, u64 tsf, u16 capability,
2220 			 u16 beacon_interval, const u8 *ie, size_t ielen,
2221 			 gfp_t gfp)
2222 {
2223 	struct cfg80211_bss *res;
2224 	struct cfg80211_non_tx_bss non_tx_data;
2225 
2226 	res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
2227 					      capability, beacon_interval, ie,
2228 					      ielen, NULL, gfp);
2229 	if (!res)
2230 		return NULL;
2231 	non_tx_data.tx_bss = res;
2232 	cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
2233 				   beacon_interval, ie, ielen, &non_tx_data,
2234 				   gfp);
2235 	return res;
2236 }
2237 EXPORT_SYMBOL(cfg80211_inform_bss_data);
2238 
2239 static void
2240 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
2241 				 struct cfg80211_inform_bss *data,
2242 				 struct ieee80211_mgmt *mgmt, size_t len,
2243 				 struct cfg80211_non_tx_bss *non_tx_data,
2244 				 gfp_t gfp)
2245 {
2246 	enum cfg80211_bss_frame_type ftype;
2247 	const u8 *ie = mgmt->u.probe_resp.variable;
2248 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2249 				      u.probe_resp.variable);
2250 
2251 	ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2252 		CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2253 
2254 	cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
2255 				   le64_to_cpu(mgmt->u.probe_resp.timestamp),
2256 				   le16_to_cpu(mgmt->u.probe_resp.beacon_int),
2257 				   ie, ielen, non_tx_data, gfp);
2258 }
2259 
2260 static void
2261 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
2262 				   struct cfg80211_bss *nontrans_bss,
2263 				   struct ieee80211_mgmt *mgmt, size_t len)
2264 {
2265 	u8 *ie, *new_ie, *pos;
2266 	const struct element *nontrans_ssid;
2267 	const u8 *trans_ssid, *mbssid;
2268 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2269 				      u.probe_resp.variable);
2270 	size_t new_ie_len;
2271 	struct cfg80211_bss_ies *new_ies;
2272 	const struct cfg80211_bss_ies *old;
2273 	u8 cpy_len;
2274 
2275 	lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
2276 
2277 	ie = mgmt->u.probe_resp.variable;
2278 
2279 	new_ie_len = ielen;
2280 	trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
2281 	if (!trans_ssid)
2282 		return;
2283 	new_ie_len -= trans_ssid[1];
2284 	mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
2285 	/*
2286 	 * It's not valid to have the MBSSID element before SSID
2287 	 * ignore if that happens - the code below assumes it is
2288 	 * after (while copying things inbetween).
2289 	 */
2290 	if (!mbssid || mbssid < trans_ssid)
2291 		return;
2292 	new_ie_len -= mbssid[1];
2293 
2294 	nontrans_ssid = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
2295 	if (!nontrans_ssid)
2296 		return;
2297 
2298 	new_ie_len += nontrans_ssid->datalen;
2299 
2300 	/* generate new ie for nontrans BSS
2301 	 * 1. replace SSID with nontrans BSS' SSID
2302 	 * 2. skip MBSSID IE
2303 	 */
2304 	new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
2305 	if (!new_ie)
2306 		return;
2307 
2308 	new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
2309 	if (!new_ies)
2310 		goto out_free;
2311 
2312 	pos = new_ie;
2313 
2314 	/* copy the nontransmitted SSID */
2315 	cpy_len = nontrans_ssid->datalen + 2;
2316 	memcpy(pos, nontrans_ssid, cpy_len);
2317 	pos += cpy_len;
2318 	/* copy the IEs between SSID and MBSSID */
2319 	cpy_len = trans_ssid[1] + 2;
2320 	memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
2321 	pos += (mbssid - (trans_ssid + cpy_len));
2322 	/* copy the IEs after MBSSID */
2323 	cpy_len = mbssid[1] + 2;
2324 	memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
2325 
2326 	/* update ie */
2327 	new_ies->len = new_ie_len;
2328 	new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2329 	new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
2330 	memcpy(new_ies->data, new_ie, new_ie_len);
2331 	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
2332 		old = rcu_access_pointer(nontrans_bss->proberesp_ies);
2333 		rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
2334 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2335 		if (old)
2336 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2337 	} else {
2338 		old = rcu_access_pointer(nontrans_bss->beacon_ies);
2339 		rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
2340 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2341 		if (old)
2342 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2343 	}
2344 
2345 out_free:
2346 	kfree(new_ie);
2347 }
2348 
2349 /* cfg80211_inform_bss_width_frame helper */
2350 static struct cfg80211_bss *
2351 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2352 				      struct cfg80211_inform_bss *data,
2353 				      struct ieee80211_mgmt *mgmt, size_t len,
2354 				      gfp_t gfp)
2355 {
2356 	struct cfg80211_internal_bss tmp = {}, *res;
2357 	struct cfg80211_bss_ies *ies;
2358 	struct ieee80211_channel *channel;
2359 	bool signal_valid;
2360 	struct ieee80211_ext *ext = NULL;
2361 	u8 *bssid, *variable;
2362 	u16 capability, beacon_int;
2363 	size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2364 					     u.probe_resp.variable);
2365 	int bss_type;
2366 	enum cfg80211_bss_frame_type ftype;
2367 
2368 	BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2369 			offsetof(struct ieee80211_mgmt, u.beacon.variable));
2370 
2371 	trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2372 
2373 	if (WARN_ON(!mgmt))
2374 		return NULL;
2375 
2376 	if (WARN_ON(!wiphy))
2377 		return NULL;
2378 
2379 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2380 		    (data->signal < 0 || data->signal > 100)))
2381 		return NULL;
2382 
2383 	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2384 		ext = (void *) mgmt;
2385 		min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2386 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2387 			min_hdr_len = offsetof(struct ieee80211_ext,
2388 					       u.s1g_short_beacon.variable);
2389 	}
2390 
2391 	if (WARN_ON(len < min_hdr_len))
2392 		return NULL;
2393 
2394 	ielen = len - min_hdr_len;
2395 	variable = mgmt->u.probe_resp.variable;
2396 	if (ext) {
2397 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2398 			variable = ext->u.s1g_short_beacon.variable;
2399 		else
2400 			variable = ext->u.s1g_beacon.variable;
2401 	}
2402 
2403 	if (ieee80211_is_beacon(mgmt->frame_control))
2404 		ftype = CFG80211_BSS_FTYPE_BEACON;
2405 	else if (ieee80211_is_probe_resp(mgmt->frame_control))
2406 		ftype = CFG80211_BSS_FTYPE_PRESP;
2407 	else
2408 		ftype = CFG80211_BSS_FTYPE_UNKNOWN;
2409 
2410 	channel = cfg80211_get_bss_channel(wiphy, variable,
2411 					   ielen, data->chan, data->scan_width,
2412 					   ftype);
2413 	if (!channel)
2414 		return NULL;
2415 
2416 	if (ext) {
2417 		const struct ieee80211_s1g_bcn_compat_ie *compat;
2418 		const struct element *elem;
2419 
2420 		elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2421 					  variable, ielen);
2422 		if (!elem)
2423 			return NULL;
2424 		if (elem->datalen < sizeof(*compat))
2425 			return NULL;
2426 		compat = (void *)elem->data;
2427 		bssid = ext->u.s1g_beacon.sa;
2428 		capability = le16_to_cpu(compat->compat_info);
2429 		beacon_int = le16_to_cpu(compat->beacon_int);
2430 	} else {
2431 		bssid = mgmt->bssid;
2432 		beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2433 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2434 	}
2435 
2436 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
2437 	if (!ies)
2438 		return NULL;
2439 	ies->len = ielen;
2440 	ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2441 	ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2442 			   ieee80211_is_s1g_beacon(mgmt->frame_control);
2443 	memcpy(ies->data, variable, ielen);
2444 
2445 	if (ieee80211_is_probe_resp(mgmt->frame_control))
2446 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2447 	else
2448 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2449 	rcu_assign_pointer(tmp.pub.ies, ies);
2450 
2451 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2452 	tmp.pub.beacon_interval = beacon_int;
2453 	tmp.pub.capability = capability;
2454 	tmp.pub.channel = channel;
2455 	tmp.pub.scan_width = data->scan_width;
2456 	tmp.pub.signal = data->signal;
2457 	tmp.ts_boottime = data->boottime_ns;
2458 	tmp.parent_tsf = data->parent_tsf;
2459 	tmp.pub.chains = data->chains;
2460 	memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2461 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2462 
2463 	signal_valid = data->chan == channel;
2464 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
2465 				  jiffies);
2466 	if (!res)
2467 		return NULL;
2468 
2469 	if (channel->band == NL80211_BAND_60GHZ) {
2470 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2471 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2472 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2473 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2474 	} else {
2475 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
2476 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2477 	}
2478 
2479 	trace_cfg80211_return_bss(&res->pub);
2480 	/* cfg80211_bss_update gives us a referenced result */
2481 	return &res->pub;
2482 }
2483 
2484 struct cfg80211_bss *
2485 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2486 			       struct cfg80211_inform_bss *data,
2487 			       struct ieee80211_mgmt *mgmt, size_t len,
2488 			       gfp_t gfp)
2489 {
2490 	struct cfg80211_bss *res, *tmp_bss;
2491 	const u8 *ie = mgmt->u.probe_resp.variable;
2492 	const struct cfg80211_bss_ies *ies1, *ies2;
2493 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2494 				      u.probe_resp.variable);
2495 	struct cfg80211_non_tx_bss non_tx_data;
2496 
2497 	res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2498 						    len, gfp);
2499 	if (!res || !wiphy->support_mbssid ||
2500 	    !cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2501 		return res;
2502 	if (wiphy->support_only_he_mbssid &&
2503 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2504 		return res;
2505 
2506 	non_tx_data.tx_bss = res;
2507 	/* process each non-transmitting bss */
2508 	cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
2509 					 &non_tx_data, gfp);
2510 
2511 	spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2512 
2513 	/* check if the res has other nontransmitting bss which is not
2514 	 * in MBSSID IE
2515 	 */
2516 	ies1 = rcu_access_pointer(res->ies);
2517 
2518 	/* go through nontrans_list, if the timestamp of the BSS is
2519 	 * earlier than the timestamp of the transmitting BSS then
2520 	 * update it
2521 	 */
2522 	list_for_each_entry(tmp_bss, &res->nontrans_list,
2523 			    nontrans_list) {
2524 		ies2 = rcu_access_pointer(tmp_bss->ies);
2525 		if (ies2->tsf < ies1->tsf)
2526 			cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
2527 							   mgmt, len);
2528 	}
2529 	spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2530 
2531 	return res;
2532 }
2533 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2534 
2535 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2536 {
2537 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2538 	struct cfg80211_internal_bss *bss;
2539 
2540 	if (!pub)
2541 		return;
2542 
2543 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2544 
2545 	spin_lock_bh(&rdev->bss_lock);
2546 	bss_ref_get(rdev, bss);
2547 	spin_unlock_bh(&rdev->bss_lock);
2548 }
2549 EXPORT_SYMBOL(cfg80211_ref_bss);
2550 
2551 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2552 {
2553 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2554 	struct cfg80211_internal_bss *bss;
2555 
2556 	if (!pub)
2557 		return;
2558 
2559 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2560 
2561 	spin_lock_bh(&rdev->bss_lock);
2562 	bss_ref_put(rdev, bss);
2563 	spin_unlock_bh(&rdev->bss_lock);
2564 }
2565 EXPORT_SYMBOL(cfg80211_put_bss);
2566 
2567 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2568 {
2569 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2570 	struct cfg80211_internal_bss *bss, *tmp1;
2571 	struct cfg80211_bss *nontrans_bss, *tmp;
2572 
2573 	if (WARN_ON(!pub))
2574 		return;
2575 
2576 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2577 
2578 	spin_lock_bh(&rdev->bss_lock);
2579 	if (list_empty(&bss->list))
2580 		goto out;
2581 
2582 	list_for_each_entry_safe(nontrans_bss, tmp,
2583 				 &pub->nontrans_list,
2584 				 nontrans_list) {
2585 		tmp1 = container_of(nontrans_bss,
2586 				    struct cfg80211_internal_bss, pub);
2587 		if (__cfg80211_unlink_bss(rdev, tmp1))
2588 			rdev->bss_generation++;
2589 	}
2590 
2591 	if (__cfg80211_unlink_bss(rdev, bss))
2592 		rdev->bss_generation++;
2593 out:
2594 	spin_unlock_bh(&rdev->bss_lock);
2595 }
2596 EXPORT_SYMBOL(cfg80211_unlink_bss);
2597 
2598 void cfg80211_bss_iter(struct wiphy *wiphy,
2599 		       struct cfg80211_chan_def *chandef,
2600 		       void (*iter)(struct wiphy *wiphy,
2601 				    struct cfg80211_bss *bss,
2602 				    void *data),
2603 		       void *iter_data)
2604 {
2605 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2606 	struct cfg80211_internal_bss *bss;
2607 
2608 	spin_lock_bh(&rdev->bss_lock);
2609 
2610 	list_for_each_entry(bss, &rdev->bss_list, list) {
2611 		if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel))
2612 			iter(wiphy, &bss->pub, iter_data);
2613 	}
2614 
2615 	spin_unlock_bh(&rdev->bss_lock);
2616 }
2617 EXPORT_SYMBOL(cfg80211_bss_iter);
2618 
2619 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
2620 				     struct ieee80211_channel *chan)
2621 {
2622 	struct wiphy *wiphy = wdev->wiphy;
2623 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2624 	struct cfg80211_internal_bss *cbss = wdev->current_bss;
2625 	struct cfg80211_internal_bss *new = NULL;
2626 	struct cfg80211_internal_bss *bss;
2627 	struct cfg80211_bss *nontrans_bss;
2628 	struct cfg80211_bss *tmp;
2629 
2630 	spin_lock_bh(&rdev->bss_lock);
2631 
2632 	/*
2633 	 * Some APs use CSA also for bandwidth changes, i.e., without actually
2634 	 * changing the control channel, so no need to update in such a case.
2635 	 */
2636 	if (cbss->pub.channel == chan)
2637 		goto done;
2638 
2639 	/* use transmitting bss */
2640 	if (cbss->pub.transmitted_bss)
2641 		cbss = container_of(cbss->pub.transmitted_bss,
2642 				    struct cfg80211_internal_bss,
2643 				    pub);
2644 
2645 	cbss->pub.channel = chan;
2646 
2647 	list_for_each_entry(bss, &rdev->bss_list, list) {
2648 		if (!cfg80211_bss_type_match(bss->pub.capability,
2649 					     bss->pub.channel->band,
2650 					     wdev->conn_bss_type))
2651 			continue;
2652 
2653 		if (bss == cbss)
2654 			continue;
2655 
2656 		if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
2657 			new = bss;
2658 			break;
2659 		}
2660 	}
2661 
2662 	if (new) {
2663 		/* to save time, update IEs for transmitting bss only */
2664 		if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
2665 			new->pub.proberesp_ies = NULL;
2666 			new->pub.beacon_ies = NULL;
2667 		}
2668 
2669 		list_for_each_entry_safe(nontrans_bss, tmp,
2670 					 &new->pub.nontrans_list,
2671 					 nontrans_list) {
2672 			bss = container_of(nontrans_bss,
2673 					   struct cfg80211_internal_bss, pub);
2674 			if (__cfg80211_unlink_bss(rdev, bss))
2675 				rdev->bss_generation++;
2676 		}
2677 
2678 		WARN_ON(atomic_read(&new->hold));
2679 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
2680 			rdev->bss_generation++;
2681 	}
2682 
2683 	rb_erase(&cbss->rbn, &rdev->bss_tree);
2684 	rb_insert_bss(rdev, cbss);
2685 	rdev->bss_generation++;
2686 
2687 	list_for_each_entry_safe(nontrans_bss, tmp,
2688 				 &cbss->pub.nontrans_list,
2689 				 nontrans_list) {
2690 		bss = container_of(nontrans_bss,
2691 				   struct cfg80211_internal_bss, pub);
2692 		bss->pub.channel = chan;
2693 		rb_erase(&bss->rbn, &rdev->bss_tree);
2694 		rb_insert_bss(rdev, bss);
2695 		rdev->bss_generation++;
2696 	}
2697 
2698 done:
2699 	spin_unlock_bh(&rdev->bss_lock);
2700 }
2701 
2702 #ifdef CONFIG_CFG80211_WEXT
2703 static struct cfg80211_registered_device *
2704 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
2705 {
2706 	struct cfg80211_registered_device *rdev;
2707 	struct net_device *dev;
2708 
2709 	ASSERT_RTNL();
2710 
2711 	dev = dev_get_by_index(net, ifindex);
2712 	if (!dev)
2713 		return ERR_PTR(-ENODEV);
2714 	if (dev->ieee80211_ptr)
2715 		rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
2716 	else
2717 		rdev = ERR_PTR(-ENODEV);
2718 	dev_put(dev);
2719 	return rdev;
2720 }
2721 
2722 int cfg80211_wext_siwscan(struct net_device *dev,
2723 			  struct iw_request_info *info,
2724 			  union iwreq_data *wrqu, char *extra)
2725 {
2726 	struct cfg80211_registered_device *rdev;
2727 	struct wiphy *wiphy;
2728 	struct iw_scan_req *wreq = NULL;
2729 	struct cfg80211_scan_request *creq;
2730 	int i, err, n_channels = 0;
2731 	enum nl80211_band band;
2732 
2733 	if (!netif_running(dev))
2734 		return -ENETDOWN;
2735 
2736 	if (wrqu->data.length == sizeof(struct iw_scan_req))
2737 		wreq = (struct iw_scan_req *)extra;
2738 
2739 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2740 
2741 	if (IS_ERR(rdev))
2742 		return PTR_ERR(rdev);
2743 
2744 	if (rdev->scan_req || rdev->scan_msg)
2745 		return -EBUSY;
2746 
2747 	wiphy = &rdev->wiphy;
2748 
2749 	/* Determine number of channels, needed to allocate creq */
2750 	if (wreq && wreq->num_channels)
2751 		n_channels = wreq->num_channels;
2752 	else
2753 		n_channels = ieee80211_get_num_supported_channels(wiphy);
2754 
2755 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2756 		       n_channels * sizeof(void *),
2757 		       GFP_ATOMIC);
2758 	if (!creq)
2759 		return -ENOMEM;
2760 
2761 	creq->wiphy = wiphy;
2762 	creq->wdev = dev->ieee80211_ptr;
2763 	/* SSIDs come after channels */
2764 	creq->ssids = (void *)&creq->channels[n_channels];
2765 	creq->n_channels = n_channels;
2766 	creq->n_ssids = 1;
2767 	creq->scan_start = jiffies;
2768 
2769 	/* translate "Scan on frequencies" request */
2770 	i = 0;
2771 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
2772 		int j;
2773 
2774 		if (!wiphy->bands[band])
2775 			continue;
2776 
2777 		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2778 			/* ignore disabled channels */
2779 			if (wiphy->bands[band]->channels[j].flags &
2780 						IEEE80211_CHAN_DISABLED)
2781 				continue;
2782 
2783 			/* If we have a wireless request structure and the
2784 			 * wireless request specifies frequencies, then search
2785 			 * for the matching hardware channel.
2786 			 */
2787 			if (wreq && wreq->num_channels) {
2788 				int k;
2789 				int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2790 				for (k = 0; k < wreq->num_channels; k++) {
2791 					struct iw_freq *freq =
2792 						&wreq->channel_list[k];
2793 					int wext_freq =
2794 						cfg80211_wext_freq(freq);
2795 
2796 					if (wext_freq == wiphy_freq)
2797 						goto wext_freq_found;
2798 				}
2799 				goto wext_freq_not_found;
2800 			}
2801 
2802 		wext_freq_found:
2803 			creq->channels[i] = &wiphy->bands[band]->channels[j];
2804 			i++;
2805 		wext_freq_not_found: ;
2806 		}
2807 	}
2808 	/* No channels found? */
2809 	if (!i) {
2810 		err = -EINVAL;
2811 		goto out;
2812 	}
2813 
2814 	/* Set real number of channels specified in creq->channels[] */
2815 	creq->n_channels = i;
2816 
2817 	/* translate "Scan for SSID" request */
2818 	if (wreq) {
2819 		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2820 			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2821 				err = -EINVAL;
2822 				goto out;
2823 			}
2824 			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2825 			creq->ssids[0].ssid_len = wreq->essid_len;
2826 		}
2827 		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2828 			creq->n_ssids = 0;
2829 	}
2830 
2831 	for (i = 0; i < NUM_NL80211_BANDS; i++)
2832 		if (wiphy->bands[i])
2833 			creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2834 
2835 	eth_broadcast_addr(creq->bssid);
2836 
2837 	wiphy_lock(&rdev->wiphy);
2838 
2839 	rdev->scan_req = creq;
2840 	err = rdev_scan(rdev, creq);
2841 	if (err) {
2842 		rdev->scan_req = NULL;
2843 		/* creq will be freed below */
2844 	} else {
2845 		nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2846 		/* creq now owned by driver */
2847 		creq = NULL;
2848 		dev_hold(dev);
2849 	}
2850 	wiphy_unlock(&rdev->wiphy);
2851  out:
2852 	kfree(creq);
2853 	return err;
2854 }
2855 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2856 
2857 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2858 				    const struct cfg80211_bss_ies *ies,
2859 				    char *current_ev, char *end_buf)
2860 {
2861 	const u8 *pos, *end, *next;
2862 	struct iw_event iwe;
2863 
2864 	if (!ies)
2865 		return current_ev;
2866 
2867 	/*
2868 	 * If needed, fragment the IEs buffer (at IE boundaries) into short
2869 	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2870 	 */
2871 	pos = ies->data;
2872 	end = pos + ies->len;
2873 
2874 	while (end - pos > IW_GENERIC_IE_MAX) {
2875 		next = pos + 2 + pos[1];
2876 		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2877 			next = next + 2 + next[1];
2878 
2879 		memset(&iwe, 0, sizeof(iwe));
2880 		iwe.cmd = IWEVGENIE;
2881 		iwe.u.data.length = next - pos;
2882 		current_ev = iwe_stream_add_point_check(info, current_ev,
2883 							end_buf, &iwe,
2884 							(void *)pos);
2885 		if (IS_ERR(current_ev))
2886 			return current_ev;
2887 		pos = next;
2888 	}
2889 
2890 	if (end > pos) {
2891 		memset(&iwe, 0, sizeof(iwe));
2892 		iwe.cmd = IWEVGENIE;
2893 		iwe.u.data.length = end - pos;
2894 		current_ev = iwe_stream_add_point_check(info, current_ev,
2895 							end_buf, &iwe,
2896 							(void *)pos);
2897 		if (IS_ERR(current_ev))
2898 			return current_ev;
2899 	}
2900 
2901 	return current_ev;
2902 }
2903 
2904 static char *
2905 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2906 	      struct cfg80211_internal_bss *bss, char *current_ev,
2907 	      char *end_buf)
2908 {
2909 	const struct cfg80211_bss_ies *ies;
2910 	struct iw_event iwe;
2911 	const u8 *ie;
2912 	u8 buf[50];
2913 	u8 *cfg, *p, *tmp;
2914 	int rem, i, sig;
2915 	bool ismesh = false;
2916 
2917 	memset(&iwe, 0, sizeof(iwe));
2918 	iwe.cmd = SIOCGIWAP;
2919 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2920 	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2921 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2922 						IW_EV_ADDR_LEN);
2923 	if (IS_ERR(current_ev))
2924 		return current_ev;
2925 
2926 	memset(&iwe, 0, sizeof(iwe));
2927 	iwe.cmd = SIOCGIWFREQ;
2928 	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2929 	iwe.u.freq.e = 0;
2930 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2931 						IW_EV_FREQ_LEN);
2932 	if (IS_ERR(current_ev))
2933 		return current_ev;
2934 
2935 	memset(&iwe, 0, sizeof(iwe));
2936 	iwe.cmd = SIOCGIWFREQ;
2937 	iwe.u.freq.m = bss->pub.channel->center_freq;
2938 	iwe.u.freq.e = 6;
2939 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2940 						IW_EV_FREQ_LEN);
2941 	if (IS_ERR(current_ev))
2942 		return current_ev;
2943 
2944 	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2945 		memset(&iwe, 0, sizeof(iwe));
2946 		iwe.cmd = IWEVQUAL;
2947 		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2948 				     IW_QUAL_NOISE_INVALID |
2949 				     IW_QUAL_QUAL_UPDATED;
2950 		switch (wiphy->signal_type) {
2951 		case CFG80211_SIGNAL_TYPE_MBM:
2952 			sig = bss->pub.signal / 100;
2953 			iwe.u.qual.level = sig;
2954 			iwe.u.qual.updated |= IW_QUAL_DBM;
2955 			if (sig < -110)		/* rather bad */
2956 				sig = -110;
2957 			else if (sig > -40)	/* perfect */
2958 				sig = -40;
2959 			/* will give a range of 0 .. 70 */
2960 			iwe.u.qual.qual = sig + 110;
2961 			break;
2962 		case CFG80211_SIGNAL_TYPE_UNSPEC:
2963 			iwe.u.qual.level = bss->pub.signal;
2964 			/* will give range 0 .. 100 */
2965 			iwe.u.qual.qual = bss->pub.signal;
2966 			break;
2967 		default:
2968 			/* not reached */
2969 			break;
2970 		}
2971 		current_ev = iwe_stream_add_event_check(info, current_ev,
2972 							end_buf, &iwe,
2973 							IW_EV_QUAL_LEN);
2974 		if (IS_ERR(current_ev))
2975 			return current_ev;
2976 	}
2977 
2978 	memset(&iwe, 0, sizeof(iwe));
2979 	iwe.cmd = SIOCGIWENCODE;
2980 	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
2981 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
2982 	else
2983 		iwe.u.data.flags = IW_ENCODE_DISABLED;
2984 	iwe.u.data.length = 0;
2985 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2986 						&iwe, "");
2987 	if (IS_ERR(current_ev))
2988 		return current_ev;
2989 
2990 	rcu_read_lock();
2991 	ies = rcu_dereference(bss->pub.ies);
2992 	rem = ies->len;
2993 	ie = ies->data;
2994 
2995 	while (rem >= 2) {
2996 		/* invalid data */
2997 		if (ie[1] > rem - 2)
2998 			break;
2999 
3000 		switch (ie[0]) {
3001 		case WLAN_EID_SSID:
3002 			memset(&iwe, 0, sizeof(iwe));
3003 			iwe.cmd = SIOCGIWESSID;
3004 			iwe.u.data.length = ie[1];
3005 			iwe.u.data.flags = 1;
3006 			current_ev = iwe_stream_add_point_check(info,
3007 								current_ev,
3008 								end_buf, &iwe,
3009 								(u8 *)ie + 2);
3010 			if (IS_ERR(current_ev))
3011 				goto unlock;
3012 			break;
3013 		case WLAN_EID_MESH_ID:
3014 			memset(&iwe, 0, sizeof(iwe));
3015 			iwe.cmd = SIOCGIWESSID;
3016 			iwe.u.data.length = ie[1];
3017 			iwe.u.data.flags = 1;
3018 			current_ev = iwe_stream_add_point_check(info,
3019 								current_ev,
3020 								end_buf, &iwe,
3021 								(u8 *)ie + 2);
3022 			if (IS_ERR(current_ev))
3023 				goto unlock;
3024 			break;
3025 		case WLAN_EID_MESH_CONFIG:
3026 			ismesh = true;
3027 			if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
3028 				break;
3029 			cfg = (u8 *)ie + 2;
3030 			memset(&iwe, 0, sizeof(iwe));
3031 			iwe.cmd = IWEVCUSTOM;
3032 			sprintf(buf, "Mesh Network Path Selection Protocol ID: "
3033 				"0x%02X", cfg[0]);
3034 			iwe.u.data.length = strlen(buf);
3035 			current_ev = iwe_stream_add_point_check(info,
3036 								current_ev,
3037 								end_buf,
3038 								&iwe, buf);
3039 			if (IS_ERR(current_ev))
3040 				goto unlock;
3041 			sprintf(buf, "Path Selection Metric ID: 0x%02X",
3042 				cfg[1]);
3043 			iwe.u.data.length = strlen(buf);
3044 			current_ev = iwe_stream_add_point_check(info,
3045 								current_ev,
3046 								end_buf,
3047 								&iwe, buf);
3048 			if (IS_ERR(current_ev))
3049 				goto unlock;
3050 			sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3051 				cfg[2]);
3052 			iwe.u.data.length = strlen(buf);
3053 			current_ev = iwe_stream_add_point_check(info,
3054 								current_ev,
3055 								end_buf,
3056 								&iwe, buf);
3057 			if (IS_ERR(current_ev))
3058 				goto unlock;
3059 			sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3060 			iwe.u.data.length = strlen(buf);
3061 			current_ev = iwe_stream_add_point_check(info,
3062 								current_ev,
3063 								end_buf,
3064 								&iwe, buf);
3065 			if (IS_ERR(current_ev))
3066 				goto unlock;
3067 			sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3068 			iwe.u.data.length = strlen(buf);
3069 			current_ev = iwe_stream_add_point_check(info,
3070 								current_ev,
3071 								end_buf,
3072 								&iwe, buf);
3073 			if (IS_ERR(current_ev))
3074 				goto unlock;
3075 			sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3076 			iwe.u.data.length = strlen(buf);
3077 			current_ev = iwe_stream_add_point_check(info,
3078 								current_ev,
3079 								end_buf,
3080 								&iwe, buf);
3081 			if (IS_ERR(current_ev))
3082 				goto unlock;
3083 			sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3084 			iwe.u.data.length = strlen(buf);
3085 			current_ev = iwe_stream_add_point_check(info,
3086 								current_ev,
3087 								end_buf,
3088 								&iwe, buf);
3089 			if (IS_ERR(current_ev))
3090 				goto unlock;
3091 			break;
3092 		case WLAN_EID_SUPP_RATES:
3093 		case WLAN_EID_EXT_SUPP_RATES:
3094 			/* display all supported rates in readable format */
3095 			p = current_ev + iwe_stream_lcp_len(info);
3096 
3097 			memset(&iwe, 0, sizeof(iwe));
3098 			iwe.cmd = SIOCGIWRATE;
3099 			/* Those two flags are ignored... */
3100 			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3101 
3102 			for (i = 0; i < ie[1]; i++) {
3103 				iwe.u.bitrate.value =
3104 					((ie[i + 2] & 0x7f) * 500000);
3105 				tmp = p;
3106 				p = iwe_stream_add_value(info, current_ev, p,
3107 							 end_buf, &iwe,
3108 							 IW_EV_PARAM_LEN);
3109 				if (p == tmp) {
3110 					current_ev = ERR_PTR(-E2BIG);
3111 					goto unlock;
3112 				}
3113 			}
3114 			current_ev = p;
3115 			break;
3116 		}
3117 		rem -= ie[1] + 2;
3118 		ie += ie[1] + 2;
3119 	}
3120 
3121 	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3122 	    ismesh) {
3123 		memset(&iwe, 0, sizeof(iwe));
3124 		iwe.cmd = SIOCGIWMODE;
3125 		if (ismesh)
3126 			iwe.u.mode = IW_MODE_MESH;
3127 		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3128 			iwe.u.mode = IW_MODE_MASTER;
3129 		else
3130 			iwe.u.mode = IW_MODE_ADHOC;
3131 		current_ev = iwe_stream_add_event_check(info, current_ev,
3132 							end_buf, &iwe,
3133 							IW_EV_UINT_LEN);
3134 		if (IS_ERR(current_ev))
3135 			goto unlock;
3136 	}
3137 
3138 	memset(&iwe, 0, sizeof(iwe));
3139 	iwe.cmd = IWEVCUSTOM;
3140 	sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3141 	iwe.u.data.length = strlen(buf);
3142 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3143 						&iwe, buf);
3144 	if (IS_ERR(current_ev))
3145 		goto unlock;
3146 	memset(&iwe, 0, sizeof(iwe));
3147 	iwe.cmd = IWEVCUSTOM;
3148 	sprintf(buf, " Last beacon: %ums ago",
3149 		elapsed_jiffies_msecs(bss->ts));
3150 	iwe.u.data.length = strlen(buf);
3151 	current_ev = iwe_stream_add_point_check(info, current_ev,
3152 						end_buf, &iwe, buf);
3153 	if (IS_ERR(current_ev))
3154 		goto unlock;
3155 
3156 	current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3157 
3158  unlock:
3159 	rcu_read_unlock();
3160 	return current_ev;
3161 }
3162 
3163 
3164 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3165 				  struct iw_request_info *info,
3166 				  char *buf, size_t len)
3167 {
3168 	char *current_ev = buf;
3169 	char *end_buf = buf + len;
3170 	struct cfg80211_internal_bss *bss;
3171 	int err = 0;
3172 
3173 	spin_lock_bh(&rdev->bss_lock);
3174 	cfg80211_bss_expire(rdev);
3175 
3176 	list_for_each_entry(bss, &rdev->bss_list, list) {
3177 		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3178 			err = -E2BIG;
3179 			break;
3180 		}
3181 		current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3182 					   current_ev, end_buf);
3183 		if (IS_ERR(current_ev)) {
3184 			err = PTR_ERR(current_ev);
3185 			break;
3186 		}
3187 	}
3188 	spin_unlock_bh(&rdev->bss_lock);
3189 
3190 	if (err)
3191 		return err;
3192 	return current_ev - buf;
3193 }
3194 
3195 
3196 int cfg80211_wext_giwscan(struct net_device *dev,
3197 			  struct iw_request_info *info,
3198 			  struct iw_point *data, char *extra)
3199 {
3200 	struct cfg80211_registered_device *rdev;
3201 	int res;
3202 
3203 	if (!netif_running(dev))
3204 		return -ENETDOWN;
3205 
3206 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3207 
3208 	if (IS_ERR(rdev))
3209 		return PTR_ERR(rdev);
3210 
3211 	if (rdev->scan_req || rdev->scan_msg)
3212 		return -EAGAIN;
3213 
3214 	res = ieee80211_scan_results(rdev, info, extra, data->length);
3215 	data->length = 0;
3216 	if (res >= 0) {
3217 		data->length = res;
3218 		res = 0;
3219 	}
3220 
3221 	return res;
3222 }
3223 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3224 #endif
3225