xref: /openbmc/linux/net/wireless/scan.c (revision c10d12e3)
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 			if (ap->multi_bss && !ap->transmitted_bssid)
705 				continue;
706 
707 			return true;
708 		}
709 
710 		if (ap->ssid_len &&
711 		    ap->ssid_len == request->ssids[i].ssid_len) {
712 			if (!memcmp(request->ssids[i].ssid, ap->ssid,
713 				    ap->ssid_len))
714 				return true;
715 		} else if (ap->short_ssid_valid) {
716 			s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
717 					   request->ssids[i].ssid_len);
718 
719 			if (ap->short_ssid == s_ssid)
720 				return true;
721 		}
722 	}
723 
724 	return false;
725 }
726 
727 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
728 {
729 	u8 i;
730 	struct cfg80211_colocated_ap *ap;
731 	int n_channels, count = 0, err;
732 	struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
733 	LIST_HEAD(coloc_ap_list);
734 	bool need_scan_psc = true;
735 	const struct ieee80211_sband_iftype_data *iftd;
736 
737 	rdev_req->scan_6ghz = true;
738 
739 	if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
740 		return -EOPNOTSUPP;
741 
742 	iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
743 					       rdev_req->wdev->iftype);
744 	if (!iftd || !iftd->he_cap.has_he)
745 		return -EOPNOTSUPP;
746 
747 	n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
748 
749 	if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
750 		struct cfg80211_internal_bss *intbss;
751 
752 		spin_lock_bh(&rdev->bss_lock);
753 		list_for_each_entry(intbss, &rdev->bss_list, list) {
754 			struct cfg80211_bss *res = &intbss->pub;
755 			const struct cfg80211_bss_ies *ies;
756 
757 			ies = rcu_access_pointer(res->ies);
758 			count += cfg80211_parse_colocated_ap(ies,
759 							     &coloc_ap_list);
760 		}
761 		spin_unlock_bh(&rdev->bss_lock);
762 	}
763 
764 	request = kzalloc(struct_size(request, channels, n_channels) +
765 			  sizeof(*request->scan_6ghz_params) * count +
766 			  sizeof(*request->ssids) * rdev_req->n_ssids,
767 			  GFP_KERNEL);
768 	if (!request) {
769 		cfg80211_free_coloc_ap_list(&coloc_ap_list);
770 		return -ENOMEM;
771 	}
772 
773 	*request = *rdev_req;
774 	request->n_channels = 0;
775 	request->scan_6ghz_params =
776 		(void *)&request->channels[n_channels];
777 
778 	/*
779 	 * PSC channels should not be scanned in case of direct scan with 1 SSID
780 	 * and at least one of the reported co-located APs with same SSID
781 	 * indicating that all APs in the same ESS are co-located
782 	 */
783 	if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
784 		list_for_each_entry(ap, &coloc_ap_list, list) {
785 			if (ap->colocated_ess &&
786 			    cfg80211_find_ssid_match(ap, request)) {
787 				need_scan_psc = false;
788 				break;
789 			}
790 		}
791 	}
792 
793 	/*
794 	 * add to the scan request the channels that need to be scanned
795 	 * regardless of the collocated APs (PSC channels or all channels
796 	 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
797 	 */
798 	for (i = 0; i < rdev_req->n_channels; i++) {
799 		if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
800 		    ((need_scan_psc &&
801 		      cfg80211_channel_is_psc(rdev_req->channels[i])) ||
802 		     !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
803 			cfg80211_scan_req_add_chan(request,
804 						   rdev_req->channels[i],
805 						   false);
806 		}
807 	}
808 
809 	if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
810 		goto skip;
811 
812 	list_for_each_entry(ap, &coloc_ap_list, list) {
813 		bool found = false;
814 		struct cfg80211_scan_6ghz_params *scan_6ghz_params =
815 			&request->scan_6ghz_params[request->n_6ghz_params];
816 		struct ieee80211_channel *chan =
817 			ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
818 
819 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
820 			continue;
821 
822 		for (i = 0; i < rdev_req->n_channels; i++) {
823 			if (rdev_req->channels[i] == chan)
824 				found = true;
825 		}
826 
827 		if (!found)
828 			continue;
829 
830 		if (request->n_ssids > 0 &&
831 		    !cfg80211_find_ssid_match(ap, request))
832 			continue;
833 
834 		if (!request->n_ssids && ap->multi_bss && !ap->transmitted_bssid)
835 			continue;
836 
837 		cfg80211_scan_req_add_chan(request, chan, true);
838 		memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
839 		scan_6ghz_params->short_ssid = ap->short_ssid;
840 		scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
841 		scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
842 
843 		/*
844 		 * If a PSC channel is added to the scan and 'need_scan_psc' is
845 		 * set to false, then all the APs that the scan logic is
846 		 * interested with on the channel are collocated and thus there
847 		 * is no need to perform the initial PSC channel listen.
848 		 */
849 		if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
850 			scan_6ghz_params->psc_no_listen = true;
851 
852 		request->n_6ghz_params++;
853 	}
854 
855 skip:
856 	cfg80211_free_coloc_ap_list(&coloc_ap_list);
857 
858 	if (request->n_channels) {
859 		struct cfg80211_scan_request *old = rdev->int_scan_req;
860 		rdev->int_scan_req = request;
861 
862 		/*
863 		 * Add the ssids from the parent scan request to the new scan
864 		 * request, so the driver would be able to use them in its
865 		 * probe requests to discover hidden APs on PSC channels.
866 		 */
867 		request->ssids = (void *)&request->channels[request->n_channels];
868 		request->n_ssids = rdev_req->n_ssids;
869 		memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) *
870 		       request->n_ssids);
871 
872 		/*
873 		 * If this scan follows a previous scan, save the scan start
874 		 * info from the first part of the scan
875 		 */
876 		if (old)
877 			rdev->int_scan_req->info = old->info;
878 
879 		err = rdev_scan(rdev, request);
880 		if (err) {
881 			rdev->int_scan_req = old;
882 			kfree(request);
883 		} else {
884 			kfree(old);
885 		}
886 
887 		return err;
888 	}
889 
890 	kfree(request);
891 	return -EINVAL;
892 }
893 
894 int cfg80211_scan(struct cfg80211_registered_device *rdev)
895 {
896 	struct cfg80211_scan_request *request;
897 	struct cfg80211_scan_request *rdev_req = rdev->scan_req;
898 	u32 n_channels = 0, idx, i;
899 
900 	if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
901 		return rdev_scan(rdev, rdev_req);
902 
903 	for (i = 0; i < rdev_req->n_channels; i++) {
904 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
905 			n_channels++;
906 	}
907 
908 	if (!n_channels)
909 		return cfg80211_scan_6ghz(rdev);
910 
911 	request = kzalloc(struct_size(request, channels, n_channels),
912 			  GFP_KERNEL);
913 	if (!request)
914 		return -ENOMEM;
915 
916 	*request = *rdev_req;
917 	request->n_channels = n_channels;
918 
919 	for (i = idx = 0; i < rdev_req->n_channels; i++) {
920 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
921 			request->channels[idx++] = rdev_req->channels[i];
922 	}
923 
924 	rdev_req->scan_6ghz = false;
925 	rdev->int_scan_req = request;
926 	return rdev_scan(rdev, request);
927 }
928 
929 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
930 			   bool send_message)
931 {
932 	struct cfg80211_scan_request *request, *rdev_req;
933 	struct wireless_dev *wdev;
934 	struct sk_buff *msg;
935 #ifdef CONFIG_CFG80211_WEXT
936 	union iwreq_data wrqu;
937 #endif
938 
939 	lockdep_assert_held(&rdev->wiphy.mtx);
940 
941 	if (rdev->scan_msg) {
942 		nl80211_send_scan_msg(rdev, rdev->scan_msg);
943 		rdev->scan_msg = NULL;
944 		return;
945 	}
946 
947 	rdev_req = rdev->scan_req;
948 	if (!rdev_req)
949 		return;
950 
951 	wdev = rdev_req->wdev;
952 	request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
953 
954 	if (wdev_running(wdev) &&
955 	    (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
956 	    !rdev_req->scan_6ghz && !request->info.aborted &&
957 	    !cfg80211_scan_6ghz(rdev))
958 		return;
959 
960 	/*
961 	 * This must be before sending the other events!
962 	 * Otherwise, wpa_supplicant gets completely confused with
963 	 * wext events.
964 	 */
965 	if (wdev->netdev)
966 		cfg80211_sme_scan_done(wdev->netdev);
967 
968 	if (!request->info.aborted &&
969 	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
970 		/* flush entries from previous scans */
971 		spin_lock_bh(&rdev->bss_lock);
972 		__cfg80211_bss_expire(rdev, request->scan_start);
973 		spin_unlock_bh(&rdev->bss_lock);
974 	}
975 
976 	msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
977 
978 #ifdef CONFIG_CFG80211_WEXT
979 	if (wdev->netdev && !request->info.aborted) {
980 		memset(&wrqu, 0, sizeof(wrqu));
981 
982 		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
983 	}
984 #endif
985 
986 	dev_put(wdev->netdev);
987 
988 	kfree(rdev->int_scan_req);
989 	rdev->int_scan_req = NULL;
990 
991 	kfree(rdev->scan_req);
992 	rdev->scan_req = NULL;
993 
994 	if (!send_message)
995 		rdev->scan_msg = msg;
996 	else
997 		nl80211_send_scan_msg(rdev, msg);
998 }
999 
1000 void __cfg80211_scan_done(struct work_struct *wk)
1001 {
1002 	struct cfg80211_registered_device *rdev;
1003 
1004 	rdev = container_of(wk, struct cfg80211_registered_device,
1005 			    scan_done_wk);
1006 
1007 	wiphy_lock(&rdev->wiphy);
1008 	___cfg80211_scan_done(rdev, true);
1009 	wiphy_unlock(&rdev->wiphy);
1010 }
1011 
1012 void cfg80211_scan_done(struct cfg80211_scan_request *request,
1013 			struct cfg80211_scan_info *info)
1014 {
1015 	struct cfg80211_scan_info old_info = request->info;
1016 
1017 	trace_cfg80211_scan_done(request, info);
1018 	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1019 		request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1020 
1021 	request->info = *info;
1022 
1023 	/*
1024 	 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1025 	 * be of the first part. In such a case old_info.scan_start_tsf should
1026 	 * be non zero.
1027 	 */
1028 	if (request->scan_6ghz && old_info.scan_start_tsf) {
1029 		request->info.scan_start_tsf = old_info.scan_start_tsf;
1030 		memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1031 		       sizeof(request->info.tsf_bssid));
1032 	}
1033 
1034 	request->notified = true;
1035 	queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1036 }
1037 EXPORT_SYMBOL(cfg80211_scan_done);
1038 
1039 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1040 				 struct cfg80211_sched_scan_request *req)
1041 {
1042 	lockdep_assert_held(&rdev->wiphy.mtx);
1043 
1044 	list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1045 }
1046 
1047 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1048 					struct cfg80211_sched_scan_request *req)
1049 {
1050 	lockdep_assert_held(&rdev->wiphy.mtx);
1051 
1052 	list_del_rcu(&req->list);
1053 	kfree_rcu(req, rcu_head);
1054 }
1055 
1056 static struct cfg80211_sched_scan_request *
1057 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1058 {
1059 	struct cfg80211_sched_scan_request *pos;
1060 
1061 	list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1062 				lockdep_is_held(&rdev->wiphy.mtx)) {
1063 		if (pos->reqid == reqid)
1064 			return pos;
1065 	}
1066 	return NULL;
1067 }
1068 
1069 /*
1070  * Determines if a scheduled scan request can be handled. When a legacy
1071  * scheduled scan is running no other scheduled scan is allowed regardless
1072  * whether the request is for legacy or multi-support scan. When a multi-support
1073  * scheduled scan is running a request for legacy scan is not allowed. In this
1074  * case a request for multi-support scan can be handled if resources are
1075  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1076  */
1077 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1078 				     bool want_multi)
1079 {
1080 	struct cfg80211_sched_scan_request *pos;
1081 	int i = 0;
1082 
1083 	list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1084 		/* request id zero means legacy in progress */
1085 		if (!i && !pos->reqid)
1086 			return -EINPROGRESS;
1087 		i++;
1088 	}
1089 
1090 	if (i) {
1091 		/* no legacy allowed when multi request(s) are active */
1092 		if (!want_multi)
1093 			return -EINPROGRESS;
1094 
1095 		/* resource limit reached */
1096 		if (i == rdev->wiphy.max_sched_scan_reqs)
1097 			return -ENOSPC;
1098 	}
1099 	return 0;
1100 }
1101 
1102 void cfg80211_sched_scan_results_wk(struct work_struct *work)
1103 {
1104 	struct cfg80211_registered_device *rdev;
1105 	struct cfg80211_sched_scan_request *req, *tmp;
1106 
1107 	rdev = container_of(work, struct cfg80211_registered_device,
1108 			   sched_scan_res_wk);
1109 
1110 	wiphy_lock(&rdev->wiphy);
1111 	list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1112 		if (req->report_results) {
1113 			req->report_results = false;
1114 			if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1115 				/* flush entries from previous scans */
1116 				spin_lock_bh(&rdev->bss_lock);
1117 				__cfg80211_bss_expire(rdev, req->scan_start);
1118 				spin_unlock_bh(&rdev->bss_lock);
1119 				req->scan_start = jiffies;
1120 			}
1121 			nl80211_send_sched_scan(req,
1122 						NL80211_CMD_SCHED_SCAN_RESULTS);
1123 		}
1124 	}
1125 	wiphy_unlock(&rdev->wiphy);
1126 }
1127 
1128 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1129 {
1130 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1131 	struct cfg80211_sched_scan_request *request;
1132 
1133 	trace_cfg80211_sched_scan_results(wiphy, reqid);
1134 	/* ignore if we're not scanning */
1135 
1136 	rcu_read_lock();
1137 	request = cfg80211_find_sched_scan_req(rdev, reqid);
1138 	if (request) {
1139 		request->report_results = true;
1140 		queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1141 	}
1142 	rcu_read_unlock();
1143 }
1144 EXPORT_SYMBOL(cfg80211_sched_scan_results);
1145 
1146 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1147 {
1148 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1149 
1150 	lockdep_assert_held(&wiphy->mtx);
1151 
1152 	trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1153 
1154 	__cfg80211_stop_sched_scan(rdev, reqid, true);
1155 }
1156 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1157 
1158 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1159 {
1160 	wiphy_lock(wiphy);
1161 	cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1162 	wiphy_unlock(wiphy);
1163 }
1164 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1165 
1166 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1167 				 struct cfg80211_sched_scan_request *req,
1168 				 bool driver_initiated)
1169 {
1170 	lockdep_assert_held(&rdev->wiphy.mtx);
1171 
1172 	if (!driver_initiated) {
1173 		int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1174 		if (err)
1175 			return err;
1176 	}
1177 
1178 	nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1179 
1180 	cfg80211_del_sched_scan_req(rdev, req);
1181 
1182 	return 0;
1183 }
1184 
1185 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1186 			       u64 reqid, bool driver_initiated)
1187 {
1188 	struct cfg80211_sched_scan_request *sched_scan_req;
1189 
1190 	lockdep_assert_held(&rdev->wiphy.mtx);
1191 
1192 	sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1193 	if (!sched_scan_req)
1194 		return -ENOENT;
1195 
1196 	return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1197 					    driver_initiated);
1198 }
1199 
1200 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1201                       unsigned long age_secs)
1202 {
1203 	struct cfg80211_internal_bss *bss;
1204 	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1205 
1206 	spin_lock_bh(&rdev->bss_lock);
1207 	list_for_each_entry(bss, &rdev->bss_list, list)
1208 		bss->ts -= age_jiffies;
1209 	spin_unlock_bh(&rdev->bss_lock);
1210 }
1211 
1212 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1213 {
1214 	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1215 }
1216 
1217 void cfg80211_bss_flush(struct wiphy *wiphy)
1218 {
1219 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1220 
1221 	spin_lock_bh(&rdev->bss_lock);
1222 	__cfg80211_bss_expire(rdev, jiffies);
1223 	spin_unlock_bh(&rdev->bss_lock);
1224 }
1225 EXPORT_SYMBOL(cfg80211_bss_flush);
1226 
1227 const struct element *
1228 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1229 			 const u8 *match, unsigned int match_len,
1230 			 unsigned int match_offset)
1231 {
1232 	const struct element *elem;
1233 
1234 	for_each_element_id(elem, eid, ies, len) {
1235 		if (elem->datalen >= match_offset + match_len &&
1236 		    !memcmp(elem->data + match_offset, match, match_len))
1237 			return elem;
1238 	}
1239 
1240 	return NULL;
1241 }
1242 EXPORT_SYMBOL(cfg80211_find_elem_match);
1243 
1244 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1245 						const u8 *ies,
1246 						unsigned int len)
1247 {
1248 	const struct element *elem;
1249 	u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1250 	int match_len = (oui_type < 0) ? 3 : sizeof(match);
1251 
1252 	if (WARN_ON(oui_type > 0xff))
1253 		return NULL;
1254 
1255 	elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1256 					match, match_len, 0);
1257 
1258 	if (!elem || elem->datalen < 4)
1259 		return NULL;
1260 
1261 	return elem;
1262 }
1263 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1264 
1265 /**
1266  * enum bss_compare_mode - BSS compare mode
1267  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1268  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1269  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1270  */
1271 enum bss_compare_mode {
1272 	BSS_CMP_REGULAR,
1273 	BSS_CMP_HIDE_ZLEN,
1274 	BSS_CMP_HIDE_NUL,
1275 };
1276 
1277 static int cmp_bss(struct cfg80211_bss *a,
1278 		   struct cfg80211_bss *b,
1279 		   enum bss_compare_mode mode)
1280 {
1281 	const struct cfg80211_bss_ies *a_ies, *b_ies;
1282 	const u8 *ie1 = NULL;
1283 	const u8 *ie2 = NULL;
1284 	int i, r;
1285 
1286 	if (a->channel != b->channel)
1287 		return b->channel->center_freq - a->channel->center_freq;
1288 
1289 	a_ies = rcu_access_pointer(a->ies);
1290 	if (!a_ies)
1291 		return -1;
1292 	b_ies = rcu_access_pointer(b->ies);
1293 	if (!b_ies)
1294 		return 1;
1295 
1296 	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1297 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1298 				       a_ies->data, a_ies->len);
1299 	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1300 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1301 				       b_ies->data, b_ies->len);
1302 	if (ie1 && ie2) {
1303 		int mesh_id_cmp;
1304 
1305 		if (ie1[1] == ie2[1])
1306 			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1307 		else
1308 			mesh_id_cmp = ie2[1] - ie1[1];
1309 
1310 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1311 				       a_ies->data, a_ies->len);
1312 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1313 				       b_ies->data, b_ies->len);
1314 		if (ie1 && ie2) {
1315 			if (mesh_id_cmp)
1316 				return mesh_id_cmp;
1317 			if (ie1[1] != ie2[1])
1318 				return ie2[1] - ie1[1];
1319 			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1320 		}
1321 	}
1322 
1323 	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1324 	if (r)
1325 		return r;
1326 
1327 	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1328 	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1329 
1330 	if (!ie1 && !ie2)
1331 		return 0;
1332 
1333 	/*
1334 	 * Note that with "hide_ssid", the function returns a match if
1335 	 * the already-present BSS ("b") is a hidden SSID beacon for
1336 	 * the new BSS ("a").
1337 	 */
1338 
1339 	/* sort missing IE before (left of) present IE */
1340 	if (!ie1)
1341 		return -1;
1342 	if (!ie2)
1343 		return 1;
1344 
1345 	switch (mode) {
1346 	case BSS_CMP_HIDE_ZLEN:
1347 		/*
1348 		 * In ZLEN mode we assume the BSS entry we're
1349 		 * looking for has a zero-length SSID. So if
1350 		 * the one we're looking at right now has that,
1351 		 * return 0. Otherwise, return the difference
1352 		 * in length, but since we're looking for the
1353 		 * 0-length it's really equivalent to returning
1354 		 * the length of the one we're looking at.
1355 		 *
1356 		 * No content comparison is needed as we assume
1357 		 * the content length is zero.
1358 		 */
1359 		return ie2[1];
1360 	case BSS_CMP_REGULAR:
1361 	default:
1362 		/* sort by length first, then by contents */
1363 		if (ie1[1] != ie2[1])
1364 			return ie2[1] - ie1[1];
1365 		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1366 	case BSS_CMP_HIDE_NUL:
1367 		if (ie1[1] != ie2[1])
1368 			return ie2[1] - ie1[1];
1369 		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1370 		for (i = 0; i < ie2[1]; i++)
1371 			if (ie2[i + 2])
1372 				return -1;
1373 		return 0;
1374 	}
1375 }
1376 
1377 static bool cfg80211_bss_type_match(u16 capability,
1378 				    enum nl80211_band band,
1379 				    enum ieee80211_bss_type bss_type)
1380 {
1381 	bool ret = true;
1382 	u16 mask, val;
1383 
1384 	if (bss_type == IEEE80211_BSS_TYPE_ANY)
1385 		return ret;
1386 
1387 	if (band == NL80211_BAND_60GHZ) {
1388 		mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1389 		switch (bss_type) {
1390 		case IEEE80211_BSS_TYPE_ESS:
1391 			val = WLAN_CAPABILITY_DMG_TYPE_AP;
1392 			break;
1393 		case IEEE80211_BSS_TYPE_PBSS:
1394 			val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1395 			break;
1396 		case IEEE80211_BSS_TYPE_IBSS:
1397 			val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1398 			break;
1399 		default:
1400 			return false;
1401 		}
1402 	} else {
1403 		mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1404 		switch (bss_type) {
1405 		case IEEE80211_BSS_TYPE_ESS:
1406 			val = WLAN_CAPABILITY_ESS;
1407 			break;
1408 		case IEEE80211_BSS_TYPE_IBSS:
1409 			val = WLAN_CAPABILITY_IBSS;
1410 			break;
1411 		case IEEE80211_BSS_TYPE_MBSS:
1412 			val = 0;
1413 			break;
1414 		default:
1415 			return false;
1416 		}
1417 	}
1418 
1419 	ret = ((capability & mask) == val);
1420 	return ret;
1421 }
1422 
1423 /* Returned bss is reference counted and must be cleaned up appropriately. */
1424 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1425 				      struct ieee80211_channel *channel,
1426 				      const u8 *bssid,
1427 				      const u8 *ssid, size_t ssid_len,
1428 				      enum ieee80211_bss_type bss_type,
1429 				      enum ieee80211_privacy privacy)
1430 {
1431 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1432 	struct cfg80211_internal_bss *bss, *res = NULL;
1433 	unsigned long now = jiffies;
1434 	int bss_privacy;
1435 
1436 	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1437 			       privacy);
1438 
1439 	spin_lock_bh(&rdev->bss_lock);
1440 
1441 	list_for_each_entry(bss, &rdev->bss_list, list) {
1442 		if (!cfg80211_bss_type_match(bss->pub.capability,
1443 					     bss->pub.channel->band, bss_type))
1444 			continue;
1445 
1446 		bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1447 		if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1448 		    (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1449 			continue;
1450 		if (channel && bss->pub.channel != channel)
1451 			continue;
1452 		if (!is_valid_ether_addr(bss->pub.bssid))
1453 			continue;
1454 		/* Don't get expired BSS structs */
1455 		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1456 		    !atomic_read(&bss->hold))
1457 			continue;
1458 		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1459 			res = bss;
1460 			bss_ref_get(rdev, res);
1461 			break;
1462 		}
1463 	}
1464 
1465 	spin_unlock_bh(&rdev->bss_lock);
1466 	if (!res)
1467 		return NULL;
1468 	trace_cfg80211_return_bss(&res->pub);
1469 	return &res->pub;
1470 }
1471 EXPORT_SYMBOL(cfg80211_get_bss);
1472 
1473 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1474 			  struct cfg80211_internal_bss *bss)
1475 {
1476 	struct rb_node **p = &rdev->bss_tree.rb_node;
1477 	struct rb_node *parent = NULL;
1478 	struct cfg80211_internal_bss *tbss;
1479 	int cmp;
1480 
1481 	while (*p) {
1482 		parent = *p;
1483 		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1484 
1485 		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1486 
1487 		if (WARN_ON(!cmp)) {
1488 			/* will sort of leak this BSS */
1489 			return;
1490 		}
1491 
1492 		if (cmp < 0)
1493 			p = &(*p)->rb_left;
1494 		else
1495 			p = &(*p)->rb_right;
1496 	}
1497 
1498 	rb_link_node(&bss->rbn, parent, p);
1499 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
1500 }
1501 
1502 static struct cfg80211_internal_bss *
1503 rb_find_bss(struct cfg80211_registered_device *rdev,
1504 	    struct cfg80211_internal_bss *res,
1505 	    enum bss_compare_mode mode)
1506 {
1507 	struct rb_node *n = rdev->bss_tree.rb_node;
1508 	struct cfg80211_internal_bss *bss;
1509 	int r;
1510 
1511 	while (n) {
1512 		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1513 		r = cmp_bss(&res->pub, &bss->pub, mode);
1514 
1515 		if (r == 0)
1516 			return bss;
1517 		else if (r < 0)
1518 			n = n->rb_left;
1519 		else
1520 			n = n->rb_right;
1521 	}
1522 
1523 	return NULL;
1524 }
1525 
1526 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1527 				   struct cfg80211_internal_bss *new)
1528 {
1529 	const struct cfg80211_bss_ies *ies;
1530 	struct cfg80211_internal_bss *bss;
1531 	const u8 *ie;
1532 	int i, ssidlen;
1533 	u8 fold = 0;
1534 	u32 n_entries = 0;
1535 
1536 	ies = rcu_access_pointer(new->pub.beacon_ies);
1537 	if (WARN_ON(!ies))
1538 		return false;
1539 
1540 	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1541 	if (!ie) {
1542 		/* nothing to do */
1543 		return true;
1544 	}
1545 
1546 	ssidlen = ie[1];
1547 	for (i = 0; i < ssidlen; i++)
1548 		fold |= ie[2 + i];
1549 
1550 	if (fold) {
1551 		/* not a hidden SSID */
1552 		return true;
1553 	}
1554 
1555 	/* This is the bad part ... */
1556 
1557 	list_for_each_entry(bss, &rdev->bss_list, list) {
1558 		/*
1559 		 * we're iterating all the entries anyway, so take the
1560 		 * opportunity to validate the list length accounting
1561 		 */
1562 		n_entries++;
1563 
1564 		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1565 			continue;
1566 		if (bss->pub.channel != new->pub.channel)
1567 			continue;
1568 		if (bss->pub.scan_width != new->pub.scan_width)
1569 			continue;
1570 		if (rcu_access_pointer(bss->pub.beacon_ies))
1571 			continue;
1572 		ies = rcu_access_pointer(bss->pub.ies);
1573 		if (!ies)
1574 			continue;
1575 		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1576 		if (!ie)
1577 			continue;
1578 		if (ssidlen && ie[1] != ssidlen)
1579 			continue;
1580 		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1581 			continue;
1582 		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1583 			list_del(&bss->hidden_list);
1584 		/* combine them */
1585 		list_add(&bss->hidden_list, &new->hidden_list);
1586 		bss->pub.hidden_beacon_bss = &new->pub;
1587 		new->refcount += bss->refcount;
1588 		rcu_assign_pointer(bss->pub.beacon_ies,
1589 				   new->pub.beacon_ies);
1590 	}
1591 
1592 	WARN_ONCE(n_entries != rdev->bss_entries,
1593 		  "rdev bss entries[%d]/list[len:%d] corruption\n",
1594 		  rdev->bss_entries, n_entries);
1595 
1596 	return true;
1597 }
1598 
1599 struct cfg80211_non_tx_bss {
1600 	struct cfg80211_bss *tx_bss;
1601 	u8 max_bssid_indicator;
1602 	u8 bssid_index;
1603 };
1604 
1605 static bool
1606 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1607 			  struct cfg80211_internal_bss *known,
1608 			  struct cfg80211_internal_bss *new,
1609 			  bool signal_valid)
1610 {
1611 	lockdep_assert_held(&rdev->bss_lock);
1612 
1613 	/* Update IEs */
1614 	if (rcu_access_pointer(new->pub.proberesp_ies)) {
1615 		const struct cfg80211_bss_ies *old;
1616 
1617 		old = rcu_access_pointer(known->pub.proberesp_ies);
1618 
1619 		rcu_assign_pointer(known->pub.proberesp_ies,
1620 				   new->pub.proberesp_ies);
1621 		/* Override possible earlier Beacon frame IEs */
1622 		rcu_assign_pointer(known->pub.ies,
1623 				   new->pub.proberesp_ies);
1624 		if (old)
1625 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1626 	} else if (rcu_access_pointer(new->pub.beacon_ies)) {
1627 		const struct cfg80211_bss_ies *old;
1628 		struct cfg80211_internal_bss *bss;
1629 
1630 		if (known->pub.hidden_beacon_bss &&
1631 		    !list_empty(&known->hidden_list)) {
1632 			const struct cfg80211_bss_ies *f;
1633 
1634 			/* The known BSS struct is one of the probe
1635 			 * response members of a group, but we're
1636 			 * receiving a beacon (beacon_ies in the new
1637 			 * bss is used). This can only mean that the
1638 			 * AP changed its beacon from not having an
1639 			 * SSID to showing it, which is confusing so
1640 			 * drop this information.
1641 			 */
1642 
1643 			f = rcu_access_pointer(new->pub.beacon_ies);
1644 			kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1645 			return false;
1646 		}
1647 
1648 		old = rcu_access_pointer(known->pub.beacon_ies);
1649 
1650 		rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1651 
1652 		/* Override IEs if they were from a beacon before */
1653 		if (old == rcu_access_pointer(known->pub.ies))
1654 			rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1655 
1656 		/* Assign beacon IEs to all sub entries */
1657 		list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1658 			const struct cfg80211_bss_ies *ies;
1659 
1660 			ies = rcu_access_pointer(bss->pub.beacon_ies);
1661 			WARN_ON(ies != old);
1662 
1663 			rcu_assign_pointer(bss->pub.beacon_ies,
1664 					   new->pub.beacon_ies);
1665 		}
1666 
1667 		if (old)
1668 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1669 	}
1670 
1671 	known->pub.beacon_interval = new->pub.beacon_interval;
1672 
1673 	/* don't update the signal if beacon was heard on
1674 	 * adjacent channel.
1675 	 */
1676 	if (signal_valid)
1677 		known->pub.signal = new->pub.signal;
1678 	known->pub.capability = new->pub.capability;
1679 	known->ts = new->ts;
1680 	known->ts_boottime = new->ts_boottime;
1681 	known->parent_tsf = new->parent_tsf;
1682 	known->pub.chains = new->pub.chains;
1683 	memcpy(known->pub.chain_signal, new->pub.chain_signal,
1684 	       IEEE80211_MAX_CHAINS);
1685 	ether_addr_copy(known->parent_bssid, new->parent_bssid);
1686 	known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1687 	known->pub.bssid_index = new->pub.bssid_index;
1688 
1689 	return true;
1690 }
1691 
1692 /* Returned bss is reference counted and must be cleaned up appropriately. */
1693 struct cfg80211_internal_bss *
1694 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1695 		    struct cfg80211_internal_bss *tmp,
1696 		    bool signal_valid, unsigned long ts)
1697 {
1698 	struct cfg80211_internal_bss *found = NULL;
1699 
1700 	if (WARN_ON(!tmp->pub.channel))
1701 		return NULL;
1702 
1703 	tmp->ts = ts;
1704 
1705 	spin_lock_bh(&rdev->bss_lock);
1706 
1707 	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1708 		spin_unlock_bh(&rdev->bss_lock);
1709 		return NULL;
1710 	}
1711 
1712 	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1713 
1714 	if (found) {
1715 		if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1716 			goto drop;
1717 	} else {
1718 		struct cfg80211_internal_bss *new;
1719 		struct cfg80211_internal_bss *hidden;
1720 		struct cfg80211_bss_ies *ies;
1721 
1722 		/*
1723 		 * create a copy -- the "res" variable that is passed in
1724 		 * is allocated on the stack since it's not needed in the
1725 		 * more common case of an update
1726 		 */
1727 		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1728 			      GFP_ATOMIC);
1729 		if (!new) {
1730 			ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1731 			if (ies)
1732 				kfree_rcu(ies, rcu_head);
1733 			ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1734 			if (ies)
1735 				kfree_rcu(ies, rcu_head);
1736 			goto drop;
1737 		}
1738 		memcpy(new, tmp, sizeof(*new));
1739 		new->refcount = 1;
1740 		INIT_LIST_HEAD(&new->hidden_list);
1741 		INIT_LIST_HEAD(&new->pub.nontrans_list);
1742 
1743 		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1744 			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1745 			if (!hidden)
1746 				hidden = rb_find_bss(rdev, tmp,
1747 						     BSS_CMP_HIDE_NUL);
1748 			if (hidden) {
1749 				new->pub.hidden_beacon_bss = &hidden->pub;
1750 				list_add(&new->hidden_list,
1751 					 &hidden->hidden_list);
1752 				hidden->refcount++;
1753 				rcu_assign_pointer(new->pub.beacon_ies,
1754 						   hidden->pub.beacon_ies);
1755 			}
1756 		} else {
1757 			/*
1758 			 * Ok so we found a beacon, and don't have an entry. If
1759 			 * it's a beacon with hidden SSID, we might be in for an
1760 			 * expensive search for any probe responses that should
1761 			 * be grouped with this beacon for updates ...
1762 			 */
1763 			if (!cfg80211_combine_bsses(rdev, new)) {
1764 				bss_ref_put(rdev, new);
1765 				goto drop;
1766 			}
1767 		}
1768 
1769 		if (rdev->bss_entries >= bss_entries_limit &&
1770 		    !cfg80211_bss_expire_oldest(rdev)) {
1771 			bss_ref_put(rdev, new);
1772 			goto drop;
1773 		}
1774 
1775 		/* This must be before the call to bss_ref_get */
1776 		if (tmp->pub.transmitted_bss) {
1777 			struct cfg80211_internal_bss *pbss =
1778 				container_of(tmp->pub.transmitted_bss,
1779 					     struct cfg80211_internal_bss,
1780 					     pub);
1781 
1782 			new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1783 			bss_ref_get(rdev, pbss);
1784 		}
1785 
1786 		list_add_tail(&new->list, &rdev->bss_list);
1787 		rdev->bss_entries++;
1788 		rb_insert_bss(rdev, new);
1789 		found = new;
1790 	}
1791 
1792 	rdev->bss_generation++;
1793 	bss_ref_get(rdev, found);
1794 	spin_unlock_bh(&rdev->bss_lock);
1795 
1796 	return found;
1797  drop:
1798 	spin_unlock_bh(&rdev->bss_lock);
1799 	return NULL;
1800 }
1801 
1802 int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen,
1803 				    enum nl80211_band band,
1804 				    enum cfg80211_bss_frame_type ftype)
1805 {
1806 	const struct element *tmp;
1807 
1808 	if (band == NL80211_BAND_6GHZ) {
1809 		struct ieee80211_he_operation *he_oper;
1810 
1811 		tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie,
1812 					     ielen);
1813 		if (tmp && tmp->datalen >= sizeof(*he_oper) &&
1814 		    tmp->datalen >= ieee80211_he_oper_size(&tmp->data[1])) {
1815 			const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
1816 
1817 			he_oper = (void *)&tmp->data[1];
1818 
1819 			he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
1820 			if (!he_6ghz_oper)
1821 				return -1;
1822 
1823 			if (ftype != CFG80211_BSS_FTYPE_BEACON ||
1824 			    he_6ghz_oper->control & IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)
1825 				return he_6ghz_oper->primary;
1826 		}
1827 	} else if (band == NL80211_BAND_S1GHZ) {
1828 		tmp = cfg80211_find_elem(WLAN_EID_S1G_OPERATION, ie, ielen);
1829 		if (tmp && tmp->datalen >= sizeof(struct ieee80211_s1g_oper_ie)) {
1830 			struct ieee80211_s1g_oper_ie *s1gop = (void *)tmp->data;
1831 
1832 			return s1gop->primary_ch;
1833 		}
1834 	} else {
1835 		tmp = cfg80211_find_elem(WLAN_EID_DS_PARAMS, ie, ielen);
1836 		if (tmp && tmp->datalen == 1)
1837 			return tmp->data[0];
1838 
1839 		tmp = cfg80211_find_elem(WLAN_EID_HT_OPERATION, ie, ielen);
1840 		if (tmp &&
1841 		    tmp->datalen >= sizeof(struct ieee80211_ht_operation)) {
1842 			struct ieee80211_ht_operation *htop = (void *)tmp->data;
1843 
1844 			return htop->primary_chan;
1845 		}
1846 	}
1847 
1848 	return -1;
1849 }
1850 EXPORT_SYMBOL(cfg80211_get_ies_channel_number);
1851 
1852 /*
1853  * Update RX channel information based on the available frame payload
1854  * information. This is mainly for the 2.4 GHz band where frames can be received
1855  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1856  * element to indicate the current (transmitting) channel, but this might also
1857  * be needed on other bands if RX frequency does not match with the actual
1858  * operating channel of a BSS, or if the AP reports a different primary channel.
1859  */
1860 static struct ieee80211_channel *
1861 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1862 			 struct ieee80211_channel *channel,
1863 			 enum nl80211_bss_scan_width scan_width,
1864 			 enum cfg80211_bss_frame_type ftype)
1865 {
1866 	u32 freq;
1867 	int channel_number;
1868 	struct ieee80211_channel *alt_channel;
1869 
1870 	channel_number = cfg80211_get_ies_channel_number(ie, ielen,
1871 							 channel->band, ftype);
1872 
1873 	if (channel_number < 0) {
1874 		/* No channel information in frame payload */
1875 		return channel;
1876 	}
1877 
1878 	freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1879 
1880 	/*
1881 	 * In 6GHz, duplicated beacon indication is relevant for
1882 	 * beacons only.
1883 	 */
1884 	if (channel->band == NL80211_BAND_6GHZ &&
1885 	    (freq == channel->center_freq ||
1886 	     abs(freq - channel->center_freq) > 80))
1887 		return channel;
1888 
1889 	alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1890 	if (!alt_channel) {
1891 		if (channel->band == NL80211_BAND_2GHZ) {
1892 			/*
1893 			 * Better not allow unexpected channels when that could
1894 			 * be going beyond the 1-11 range (e.g., discovering
1895 			 * BSS on channel 12 when radio is configured for
1896 			 * channel 11.
1897 			 */
1898 			return NULL;
1899 		}
1900 
1901 		/* No match for the payload channel number - ignore it */
1902 		return channel;
1903 	}
1904 
1905 	if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1906 	    scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1907 		/*
1908 		 * Ignore channel number in 5 and 10 MHz channels where there
1909 		 * may not be an n:1 or 1:n mapping between frequencies and
1910 		 * channel numbers.
1911 		 */
1912 		return channel;
1913 	}
1914 
1915 	/*
1916 	 * Use the channel determined through the payload channel number
1917 	 * instead of the RX channel reported by the driver.
1918 	 */
1919 	if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1920 		return NULL;
1921 	return alt_channel;
1922 }
1923 
1924 /* Returned bss is reference counted and must be cleaned up appropriately. */
1925 static struct cfg80211_bss *
1926 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1927 				struct cfg80211_inform_bss *data,
1928 				enum cfg80211_bss_frame_type ftype,
1929 				const u8 *bssid, u64 tsf, u16 capability,
1930 				u16 beacon_interval, const u8 *ie, size_t ielen,
1931 				struct cfg80211_non_tx_bss *non_tx_data,
1932 				gfp_t gfp)
1933 {
1934 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1935 	struct cfg80211_bss_ies *ies;
1936 	struct ieee80211_channel *channel;
1937 	struct cfg80211_internal_bss tmp = {}, *res;
1938 	int bss_type;
1939 	bool signal_valid;
1940 	unsigned long ts;
1941 
1942 	if (WARN_ON(!wiphy))
1943 		return NULL;
1944 
1945 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1946 		    (data->signal < 0 || data->signal > 100)))
1947 		return NULL;
1948 
1949 	channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1950 					   data->scan_width, ftype);
1951 	if (!channel)
1952 		return NULL;
1953 
1954 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1955 	tmp.pub.channel = channel;
1956 	tmp.pub.scan_width = data->scan_width;
1957 	tmp.pub.signal = data->signal;
1958 	tmp.pub.beacon_interval = beacon_interval;
1959 	tmp.pub.capability = capability;
1960 	tmp.ts_boottime = data->boottime_ns;
1961 	tmp.parent_tsf = data->parent_tsf;
1962 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1963 
1964 	if (non_tx_data) {
1965 		tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1966 		ts = bss_from_pub(non_tx_data->tx_bss)->ts;
1967 		tmp.pub.bssid_index = non_tx_data->bssid_index;
1968 		tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1969 	} else {
1970 		ts = jiffies;
1971 	}
1972 
1973 	/*
1974 	 * If we do not know here whether the IEs are from a Beacon or Probe
1975 	 * Response frame, we need to pick one of the options and only use it
1976 	 * with the driver that does not provide the full Beacon/Probe Response
1977 	 * frame. Use Beacon frame pointer to avoid indicating that this should
1978 	 * override the IEs pointer should we have received an earlier
1979 	 * indication of Probe Response data.
1980 	 */
1981 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
1982 	if (!ies)
1983 		return NULL;
1984 	ies->len = ielen;
1985 	ies->tsf = tsf;
1986 	ies->from_beacon = false;
1987 	memcpy(ies->data, ie, ielen);
1988 
1989 	switch (ftype) {
1990 	case CFG80211_BSS_FTYPE_BEACON:
1991 		ies->from_beacon = true;
1992 		fallthrough;
1993 	case CFG80211_BSS_FTYPE_UNKNOWN:
1994 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1995 		break;
1996 	case CFG80211_BSS_FTYPE_PRESP:
1997 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1998 		break;
1999 	}
2000 	rcu_assign_pointer(tmp.pub.ies, ies);
2001 
2002 	signal_valid = data->chan == channel;
2003 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
2004 	if (!res)
2005 		return NULL;
2006 
2007 	if (channel->band == NL80211_BAND_60GHZ) {
2008 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2009 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2010 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2011 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2012 	} else {
2013 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
2014 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2015 	}
2016 
2017 	if (non_tx_data) {
2018 		/* this is a nontransmitting bss, we need to add it to
2019 		 * transmitting bss' list if it is not there
2020 		 */
2021 		if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
2022 					       &res->pub)) {
2023 			if (__cfg80211_unlink_bss(rdev, res))
2024 				rdev->bss_generation++;
2025 		}
2026 	}
2027 
2028 	trace_cfg80211_return_bss(&res->pub);
2029 	/* cfg80211_bss_update gives us a referenced result */
2030 	return &res->pub;
2031 }
2032 
2033 static const struct element
2034 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
2035 				   const struct element *mbssid_elem,
2036 				   const struct element *sub_elem)
2037 {
2038 	const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
2039 	const struct element *next_mbssid;
2040 	const struct element *next_sub;
2041 
2042 	next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2043 					 mbssid_end,
2044 					 ielen - (mbssid_end - ie));
2045 
2046 	/*
2047 	 * If it is not the last subelement in current MBSSID IE or there isn't
2048 	 * a next MBSSID IE - profile is complete.
2049 	*/
2050 	if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2051 	    !next_mbssid)
2052 		return NULL;
2053 
2054 	/* For any length error, just return NULL */
2055 
2056 	if (next_mbssid->datalen < 4)
2057 		return NULL;
2058 
2059 	next_sub = (void *)&next_mbssid->data[1];
2060 
2061 	if (next_mbssid->data + next_mbssid->datalen <
2062 	    next_sub->data + next_sub->datalen)
2063 		return NULL;
2064 
2065 	if (next_sub->id != 0 || next_sub->datalen < 2)
2066 		return NULL;
2067 
2068 	/*
2069 	 * Check if the first element in the next sub element is a start
2070 	 * of a new profile
2071 	 */
2072 	return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2073 	       NULL : next_mbssid;
2074 }
2075 
2076 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2077 			      const struct element *mbssid_elem,
2078 			      const struct element *sub_elem,
2079 			      u8 *merged_ie, size_t max_copy_len)
2080 {
2081 	size_t copied_len = sub_elem->datalen;
2082 	const struct element *next_mbssid;
2083 
2084 	if (sub_elem->datalen > max_copy_len)
2085 		return 0;
2086 
2087 	memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2088 
2089 	while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2090 								mbssid_elem,
2091 								sub_elem))) {
2092 		const struct element *next_sub = (void *)&next_mbssid->data[1];
2093 
2094 		if (copied_len + next_sub->datalen > max_copy_len)
2095 			break;
2096 		memcpy(merged_ie + copied_len, next_sub->data,
2097 		       next_sub->datalen);
2098 		copied_len += next_sub->datalen;
2099 	}
2100 
2101 	return copied_len;
2102 }
2103 EXPORT_SYMBOL(cfg80211_merge_profile);
2104 
2105 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2106 				       struct cfg80211_inform_bss *data,
2107 				       enum cfg80211_bss_frame_type ftype,
2108 				       const u8 *bssid, u64 tsf,
2109 				       u16 beacon_interval, const u8 *ie,
2110 				       size_t ielen,
2111 				       struct cfg80211_non_tx_bss *non_tx_data,
2112 				       gfp_t gfp)
2113 {
2114 	const u8 *mbssid_index_ie;
2115 	const struct element *elem, *sub;
2116 	size_t new_ie_len;
2117 	u8 new_bssid[ETH_ALEN];
2118 	u8 *new_ie, *profile;
2119 	u64 seen_indices = 0;
2120 	u16 capability;
2121 	struct cfg80211_bss *bss;
2122 
2123 	if (!non_tx_data)
2124 		return;
2125 	if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2126 		return;
2127 	if (!wiphy->support_mbssid)
2128 		return;
2129 	if (wiphy->support_only_he_mbssid &&
2130 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2131 		return;
2132 
2133 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2134 	if (!new_ie)
2135 		return;
2136 
2137 	profile = kmalloc(ielen, gfp);
2138 	if (!profile)
2139 		goto out;
2140 
2141 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
2142 		if (elem->datalen < 4)
2143 			continue;
2144 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2145 			u8 profile_len;
2146 
2147 			if (sub->id != 0 || sub->datalen < 4) {
2148 				/* not a valid BSS profile */
2149 				continue;
2150 			}
2151 
2152 			if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2153 			    sub->data[1] != 2) {
2154 				/* The first element within the Nontransmitted
2155 				 * BSSID Profile is not the Nontransmitted
2156 				 * BSSID Capability element.
2157 				 */
2158 				continue;
2159 			}
2160 
2161 			memset(profile, 0, ielen);
2162 			profile_len = cfg80211_merge_profile(ie, ielen,
2163 							     elem,
2164 							     sub,
2165 							     profile,
2166 							     ielen);
2167 
2168 			/* found a Nontransmitted BSSID Profile */
2169 			mbssid_index_ie = cfg80211_find_ie
2170 				(WLAN_EID_MULTI_BSSID_IDX,
2171 				 profile, profile_len);
2172 			if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2173 			    mbssid_index_ie[2] == 0 ||
2174 			    mbssid_index_ie[2] > 46) {
2175 				/* No valid Multiple BSSID-Index element */
2176 				continue;
2177 			}
2178 
2179 			if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2180 				/* We don't support legacy split of a profile */
2181 				net_dbg_ratelimited("Partial info for BSSID index %d\n",
2182 						    mbssid_index_ie[2]);
2183 
2184 			seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2185 
2186 			non_tx_data->bssid_index = mbssid_index_ie[2];
2187 			non_tx_data->max_bssid_indicator = elem->data[0];
2188 
2189 			cfg80211_gen_new_bssid(bssid,
2190 					       non_tx_data->max_bssid_indicator,
2191 					       non_tx_data->bssid_index,
2192 					       new_bssid);
2193 			memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2194 			new_ie_len = cfg80211_gen_new_ie(ie, ielen,
2195 							 profile,
2196 							 profile_len, new_ie,
2197 							 gfp);
2198 			if (!new_ie_len)
2199 				continue;
2200 
2201 			capability = get_unaligned_le16(profile + 2);
2202 			bss = cfg80211_inform_single_bss_data(wiphy, data,
2203 							      ftype,
2204 							      new_bssid, tsf,
2205 							      capability,
2206 							      beacon_interval,
2207 							      new_ie,
2208 							      new_ie_len,
2209 							      non_tx_data,
2210 							      gfp);
2211 			if (!bss)
2212 				break;
2213 			cfg80211_put_bss(wiphy, bss);
2214 		}
2215 	}
2216 
2217 out:
2218 	kfree(new_ie);
2219 	kfree(profile);
2220 }
2221 
2222 struct cfg80211_bss *
2223 cfg80211_inform_bss_data(struct wiphy *wiphy,
2224 			 struct cfg80211_inform_bss *data,
2225 			 enum cfg80211_bss_frame_type ftype,
2226 			 const u8 *bssid, u64 tsf, u16 capability,
2227 			 u16 beacon_interval, const u8 *ie, size_t ielen,
2228 			 gfp_t gfp)
2229 {
2230 	struct cfg80211_bss *res;
2231 	struct cfg80211_non_tx_bss non_tx_data;
2232 
2233 	res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
2234 					      capability, beacon_interval, ie,
2235 					      ielen, NULL, gfp);
2236 	if (!res)
2237 		return NULL;
2238 	non_tx_data.tx_bss = res;
2239 	cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
2240 				   beacon_interval, ie, ielen, &non_tx_data,
2241 				   gfp);
2242 	return res;
2243 }
2244 EXPORT_SYMBOL(cfg80211_inform_bss_data);
2245 
2246 static void
2247 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
2248 				 struct cfg80211_inform_bss *data,
2249 				 struct ieee80211_mgmt *mgmt, size_t len,
2250 				 struct cfg80211_non_tx_bss *non_tx_data,
2251 				 gfp_t gfp)
2252 {
2253 	enum cfg80211_bss_frame_type ftype;
2254 	const u8 *ie = mgmt->u.probe_resp.variable;
2255 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2256 				      u.probe_resp.variable);
2257 
2258 	ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2259 		CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2260 
2261 	cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
2262 				   le64_to_cpu(mgmt->u.probe_resp.timestamp),
2263 				   le16_to_cpu(mgmt->u.probe_resp.beacon_int),
2264 				   ie, ielen, non_tx_data, gfp);
2265 }
2266 
2267 static void
2268 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
2269 				   struct cfg80211_bss *nontrans_bss,
2270 				   struct ieee80211_mgmt *mgmt, size_t len)
2271 {
2272 	u8 *ie, *new_ie, *pos;
2273 	const struct element *nontrans_ssid;
2274 	const u8 *trans_ssid, *mbssid;
2275 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2276 				      u.probe_resp.variable);
2277 	size_t new_ie_len;
2278 	struct cfg80211_bss_ies *new_ies;
2279 	const struct cfg80211_bss_ies *old;
2280 	u8 cpy_len;
2281 
2282 	lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
2283 
2284 	ie = mgmt->u.probe_resp.variable;
2285 
2286 	new_ie_len = ielen;
2287 	trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
2288 	if (!trans_ssid)
2289 		return;
2290 	new_ie_len -= trans_ssid[1];
2291 	mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
2292 	/*
2293 	 * It's not valid to have the MBSSID element before SSID
2294 	 * ignore if that happens - the code below assumes it is
2295 	 * after (while copying things inbetween).
2296 	 */
2297 	if (!mbssid || mbssid < trans_ssid)
2298 		return;
2299 	new_ie_len -= mbssid[1];
2300 
2301 	nontrans_ssid = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
2302 	if (!nontrans_ssid)
2303 		return;
2304 
2305 	new_ie_len += nontrans_ssid->datalen;
2306 
2307 	/* generate new ie for nontrans BSS
2308 	 * 1. replace SSID with nontrans BSS' SSID
2309 	 * 2. skip MBSSID IE
2310 	 */
2311 	new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
2312 	if (!new_ie)
2313 		return;
2314 
2315 	new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
2316 	if (!new_ies)
2317 		goto out_free;
2318 
2319 	pos = new_ie;
2320 
2321 	/* copy the nontransmitted SSID */
2322 	cpy_len = nontrans_ssid->datalen + 2;
2323 	memcpy(pos, nontrans_ssid, cpy_len);
2324 	pos += cpy_len;
2325 	/* copy the IEs between SSID and MBSSID */
2326 	cpy_len = trans_ssid[1] + 2;
2327 	memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
2328 	pos += (mbssid - (trans_ssid + cpy_len));
2329 	/* copy the IEs after MBSSID */
2330 	cpy_len = mbssid[1] + 2;
2331 	memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
2332 
2333 	/* update ie */
2334 	new_ies->len = new_ie_len;
2335 	new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2336 	new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
2337 	memcpy(new_ies->data, new_ie, new_ie_len);
2338 	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
2339 		old = rcu_access_pointer(nontrans_bss->proberesp_ies);
2340 		rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
2341 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2342 		if (old)
2343 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2344 	} else {
2345 		old = rcu_access_pointer(nontrans_bss->beacon_ies);
2346 		rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
2347 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2348 		if (old)
2349 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2350 	}
2351 
2352 out_free:
2353 	kfree(new_ie);
2354 }
2355 
2356 /* cfg80211_inform_bss_width_frame helper */
2357 static struct cfg80211_bss *
2358 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2359 				      struct cfg80211_inform_bss *data,
2360 				      struct ieee80211_mgmt *mgmt, size_t len,
2361 				      gfp_t gfp)
2362 {
2363 	struct cfg80211_internal_bss tmp = {}, *res;
2364 	struct cfg80211_bss_ies *ies;
2365 	struct ieee80211_channel *channel;
2366 	bool signal_valid;
2367 	struct ieee80211_ext *ext = NULL;
2368 	u8 *bssid, *variable;
2369 	u16 capability, beacon_int;
2370 	size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2371 					     u.probe_resp.variable);
2372 	int bss_type;
2373 	enum cfg80211_bss_frame_type ftype;
2374 
2375 	BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2376 			offsetof(struct ieee80211_mgmt, u.beacon.variable));
2377 
2378 	trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2379 
2380 	if (WARN_ON(!mgmt))
2381 		return NULL;
2382 
2383 	if (WARN_ON(!wiphy))
2384 		return NULL;
2385 
2386 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2387 		    (data->signal < 0 || data->signal > 100)))
2388 		return NULL;
2389 
2390 	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2391 		ext = (void *) mgmt;
2392 		min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2393 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2394 			min_hdr_len = offsetof(struct ieee80211_ext,
2395 					       u.s1g_short_beacon.variable);
2396 	}
2397 
2398 	if (WARN_ON(len < min_hdr_len))
2399 		return NULL;
2400 
2401 	ielen = len - min_hdr_len;
2402 	variable = mgmt->u.probe_resp.variable;
2403 	if (ext) {
2404 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2405 			variable = ext->u.s1g_short_beacon.variable;
2406 		else
2407 			variable = ext->u.s1g_beacon.variable;
2408 	}
2409 
2410 	if (ieee80211_is_beacon(mgmt->frame_control))
2411 		ftype = CFG80211_BSS_FTYPE_BEACON;
2412 	else if (ieee80211_is_probe_resp(mgmt->frame_control))
2413 		ftype = CFG80211_BSS_FTYPE_PRESP;
2414 	else
2415 		ftype = CFG80211_BSS_FTYPE_UNKNOWN;
2416 
2417 	channel = cfg80211_get_bss_channel(wiphy, variable,
2418 					   ielen, data->chan, data->scan_width,
2419 					   ftype);
2420 	if (!channel)
2421 		return NULL;
2422 
2423 	if (ext) {
2424 		const struct ieee80211_s1g_bcn_compat_ie *compat;
2425 		const struct element *elem;
2426 
2427 		elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2428 					  variable, ielen);
2429 		if (!elem)
2430 			return NULL;
2431 		if (elem->datalen < sizeof(*compat))
2432 			return NULL;
2433 		compat = (void *)elem->data;
2434 		bssid = ext->u.s1g_beacon.sa;
2435 		capability = le16_to_cpu(compat->compat_info);
2436 		beacon_int = le16_to_cpu(compat->beacon_int);
2437 	} else {
2438 		bssid = mgmt->bssid;
2439 		beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2440 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2441 	}
2442 
2443 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
2444 	if (!ies)
2445 		return NULL;
2446 	ies->len = ielen;
2447 	ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2448 	ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2449 			   ieee80211_is_s1g_beacon(mgmt->frame_control);
2450 	memcpy(ies->data, variable, ielen);
2451 
2452 	if (ieee80211_is_probe_resp(mgmt->frame_control))
2453 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2454 	else
2455 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2456 	rcu_assign_pointer(tmp.pub.ies, ies);
2457 
2458 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2459 	tmp.pub.beacon_interval = beacon_int;
2460 	tmp.pub.capability = capability;
2461 	tmp.pub.channel = channel;
2462 	tmp.pub.scan_width = data->scan_width;
2463 	tmp.pub.signal = data->signal;
2464 	tmp.ts_boottime = data->boottime_ns;
2465 	tmp.parent_tsf = data->parent_tsf;
2466 	tmp.pub.chains = data->chains;
2467 	memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2468 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2469 
2470 	signal_valid = data->chan == channel;
2471 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
2472 				  jiffies);
2473 	if (!res)
2474 		return NULL;
2475 
2476 	if (channel->band == NL80211_BAND_60GHZ) {
2477 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2478 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2479 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2480 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2481 	} else {
2482 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
2483 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2484 	}
2485 
2486 	trace_cfg80211_return_bss(&res->pub);
2487 	/* cfg80211_bss_update gives us a referenced result */
2488 	return &res->pub;
2489 }
2490 
2491 struct cfg80211_bss *
2492 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2493 			       struct cfg80211_inform_bss *data,
2494 			       struct ieee80211_mgmt *mgmt, size_t len,
2495 			       gfp_t gfp)
2496 {
2497 	struct cfg80211_bss *res, *tmp_bss;
2498 	const u8 *ie = mgmt->u.probe_resp.variable;
2499 	const struct cfg80211_bss_ies *ies1, *ies2;
2500 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2501 				      u.probe_resp.variable);
2502 	struct cfg80211_non_tx_bss non_tx_data;
2503 
2504 	res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2505 						    len, gfp);
2506 	if (!res || !wiphy->support_mbssid ||
2507 	    !cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2508 		return res;
2509 	if (wiphy->support_only_he_mbssid &&
2510 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2511 		return res;
2512 
2513 	non_tx_data.tx_bss = res;
2514 	/* process each non-transmitting bss */
2515 	cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
2516 					 &non_tx_data, gfp);
2517 
2518 	spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2519 
2520 	/* check if the res has other nontransmitting bss which is not
2521 	 * in MBSSID IE
2522 	 */
2523 	ies1 = rcu_access_pointer(res->ies);
2524 
2525 	/* go through nontrans_list, if the timestamp of the BSS is
2526 	 * earlier than the timestamp of the transmitting BSS then
2527 	 * update it
2528 	 */
2529 	list_for_each_entry(tmp_bss, &res->nontrans_list,
2530 			    nontrans_list) {
2531 		ies2 = rcu_access_pointer(tmp_bss->ies);
2532 		if (ies2->tsf < ies1->tsf)
2533 			cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
2534 							   mgmt, len);
2535 	}
2536 	spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2537 
2538 	return res;
2539 }
2540 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2541 
2542 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2543 {
2544 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2545 	struct cfg80211_internal_bss *bss;
2546 
2547 	if (!pub)
2548 		return;
2549 
2550 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2551 
2552 	spin_lock_bh(&rdev->bss_lock);
2553 	bss_ref_get(rdev, bss);
2554 	spin_unlock_bh(&rdev->bss_lock);
2555 }
2556 EXPORT_SYMBOL(cfg80211_ref_bss);
2557 
2558 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2559 {
2560 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2561 	struct cfg80211_internal_bss *bss;
2562 
2563 	if (!pub)
2564 		return;
2565 
2566 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2567 
2568 	spin_lock_bh(&rdev->bss_lock);
2569 	bss_ref_put(rdev, bss);
2570 	spin_unlock_bh(&rdev->bss_lock);
2571 }
2572 EXPORT_SYMBOL(cfg80211_put_bss);
2573 
2574 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2575 {
2576 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2577 	struct cfg80211_internal_bss *bss, *tmp1;
2578 	struct cfg80211_bss *nontrans_bss, *tmp;
2579 
2580 	if (WARN_ON(!pub))
2581 		return;
2582 
2583 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2584 
2585 	spin_lock_bh(&rdev->bss_lock);
2586 	if (list_empty(&bss->list))
2587 		goto out;
2588 
2589 	list_for_each_entry_safe(nontrans_bss, tmp,
2590 				 &pub->nontrans_list,
2591 				 nontrans_list) {
2592 		tmp1 = container_of(nontrans_bss,
2593 				    struct cfg80211_internal_bss, pub);
2594 		if (__cfg80211_unlink_bss(rdev, tmp1))
2595 			rdev->bss_generation++;
2596 	}
2597 
2598 	if (__cfg80211_unlink_bss(rdev, bss))
2599 		rdev->bss_generation++;
2600 out:
2601 	spin_unlock_bh(&rdev->bss_lock);
2602 }
2603 EXPORT_SYMBOL(cfg80211_unlink_bss);
2604 
2605 void cfg80211_bss_iter(struct wiphy *wiphy,
2606 		       struct cfg80211_chan_def *chandef,
2607 		       void (*iter)(struct wiphy *wiphy,
2608 				    struct cfg80211_bss *bss,
2609 				    void *data),
2610 		       void *iter_data)
2611 {
2612 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2613 	struct cfg80211_internal_bss *bss;
2614 
2615 	spin_lock_bh(&rdev->bss_lock);
2616 
2617 	list_for_each_entry(bss, &rdev->bss_list, list) {
2618 		if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel))
2619 			iter(wiphy, &bss->pub, iter_data);
2620 	}
2621 
2622 	spin_unlock_bh(&rdev->bss_lock);
2623 }
2624 EXPORT_SYMBOL(cfg80211_bss_iter);
2625 
2626 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
2627 				     struct ieee80211_channel *chan)
2628 {
2629 	struct wiphy *wiphy = wdev->wiphy;
2630 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2631 	struct cfg80211_internal_bss *cbss = wdev->current_bss;
2632 	struct cfg80211_internal_bss *new = NULL;
2633 	struct cfg80211_internal_bss *bss;
2634 	struct cfg80211_bss *nontrans_bss;
2635 	struct cfg80211_bss *tmp;
2636 
2637 	spin_lock_bh(&rdev->bss_lock);
2638 
2639 	/*
2640 	 * Some APs use CSA also for bandwidth changes, i.e., without actually
2641 	 * changing the control channel, so no need to update in such a case.
2642 	 */
2643 	if (cbss->pub.channel == chan)
2644 		goto done;
2645 
2646 	/* use transmitting bss */
2647 	if (cbss->pub.transmitted_bss)
2648 		cbss = container_of(cbss->pub.transmitted_bss,
2649 				    struct cfg80211_internal_bss,
2650 				    pub);
2651 
2652 	cbss->pub.channel = chan;
2653 
2654 	list_for_each_entry(bss, &rdev->bss_list, list) {
2655 		if (!cfg80211_bss_type_match(bss->pub.capability,
2656 					     bss->pub.channel->band,
2657 					     wdev->conn_bss_type))
2658 			continue;
2659 
2660 		if (bss == cbss)
2661 			continue;
2662 
2663 		if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
2664 			new = bss;
2665 			break;
2666 		}
2667 	}
2668 
2669 	if (new) {
2670 		/* to save time, update IEs for transmitting bss only */
2671 		if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
2672 			new->pub.proberesp_ies = NULL;
2673 			new->pub.beacon_ies = NULL;
2674 		}
2675 
2676 		list_for_each_entry_safe(nontrans_bss, tmp,
2677 					 &new->pub.nontrans_list,
2678 					 nontrans_list) {
2679 			bss = container_of(nontrans_bss,
2680 					   struct cfg80211_internal_bss, pub);
2681 			if (__cfg80211_unlink_bss(rdev, bss))
2682 				rdev->bss_generation++;
2683 		}
2684 
2685 		WARN_ON(atomic_read(&new->hold));
2686 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
2687 			rdev->bss_generation++;
2688 	}
2689 
2690 	rb_erase(&cbss->rbn, &rdev->bss_tree);
2691 	rb_insert_bss(rdev, cbss);
2692 	rdev->bss_generation++;
2693 
2694 	list_for_each_entry_safe(nontrans_bss, tmp,
2695 				 &cbss->pub.nontrans_list,
2696 				 nontrans_list) {
2697 		bss = container_of(nontrans_bss,
2698 				   struct cfg80211_internal_bss, pub);
2699 		bss->pub.channel = chan;
2700 		rb_erase(&bss->rbn, &rdev->bss_tree);
2701 		rb_insert_bss(rdev, bss);
2702 		rdev->bss_generation++;
2703 	}
2704 
2705 done:
2706 	spin_unlock_bh(&rdev->bss_lock);
2707 }
2708 
2709 #ifdef CONFIG_CFG80211_WEXT
2710 static struct cfg80211_registered_device *
2711 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
2712 {
2713 	struct cfg80211_registered_device *rdev;
2714 	struct net_device *dev;
2715 
2716 	ASSERT_RTNL();
2717 
2718 	dev = dev_get_by_index(net, ifindex);
2719 	if (!dev)
2720 		return ERR_PTR(-ENODEV);
2721 	if (dev->ieee80211_ptr)
2722 		rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
2723 	else
2724 		rdev = ERR_PTR(-ENODEV);
2725 	dev_put(dev);
2726 	return rdev;
2727 }
2728 
2729 int cfg80211_wext_siwscan(struct net_device *dev,
2730 			  struct iw_request_info *info,
2731 			  union iwreq_data *wrqu, char *extra)
2732 {
2733 	struct cfg80211_registered_device *rdev;
2734 	struct wiphy *wiphy;
2735 	struct iw_scan_req *wreq = NULL;
2736 	struct cfg80211_scan_request *creq;
2737 	int i, err, n_channels = 0;
2738 	enum nl80211_band band;
2739 
2740 	if (!netif_running(dev))
2741 		return -ENETDOWN;
2742 
2743 	if (wrqu->data.length == sizeof(struct iw_scan_req))
2744 		wreq = (struct iw_scan_req *)extra;
2745 
2746 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2747 
2748 	if (IS_ERR(rdev))
2749 		return PTR_ERR(rdev);
2750 
2751 	if (rdev->scan_req || rdev->scan_msg)
2752 		return -EBUSY;
2753 
2754 	wiphy = &rdev->wiphy;
2755 
2756 	/* Determine number of channels, needed to allocate creq */
2757 	if (wreq && wreq->num_channels)
2758 		n_channels = wreq->num_channels;
2759 	else
2760 		n_channels = ieee80211_get_num_supported_channels(wiphy);
2761 
2762 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2763 		       n_channels * sizeof(void *),
2764 		       GFP_ATOMIC);
2765 	if (!creq)
2766 		return -ENOMEM;
2767 
2768 	creq->wiphy = wiphy;
2769 	creq->wdev = dev->ieee80211_ptr;
2770 	/* SSIDs come after channels */
2771 	creq->ssids = (void *)&creq->channels[n_channels];
2772 	creq->n_channels = n_channels;
2773 	creq->n_ssids = 1;
2774 	creq->scan_start = jiffies;
2775 
2776 	/* translate "Scan on frequencies" request */
2777 	i = 0;
2778 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
2779 		int j;
2780 
2781 		if (!wiphy->bands[band])
2782 			continue;
2783 
2784 		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2785 			/* ignore disabled channels */
2786 			if (wiphy->bands[band]->channels[j].flags &
2787 						IEEE80211_CHAN_DISABLED)
2788 				continue;
2789 
2790 			/* If we have a wireless request structure and the
2791 			 * wireless request specifies frequencies, then search
2792 			 * for the matching hardware channel.
2793 			 */
2794 			if (wreq && wreq->num_channels) {
2795 				int k;
2796 				int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2797 				for (k = 0; k < wreq->num_channels; k++) {
2798 					struct iw_freq *freq =
2799 						&wreq->channel_list[k];
2800 					int wext_freq =
2801 						cfg80211_wext_freq(freq);
2802 
2803 					if (wext_freq == wiphy_freq)
2804 						goto wext_freq_found;
2805 				}
2806 				goto wext_freq_not_found;
2807 			}
2808 
2809 		wext_freq_found:
2810 			creq->channels[i] = &wiphy->bands[band]->channels[j];
2811 			i++;
2812 		wext_freq_not_found: ;
2813 		}
2814 	}
2815 	/* No channels found? */
2816 	if (!i) {
2817 		err = -EINVAL;
2818 		goto out;
2819 	}
2820 
2821 	/* Set real number of channels specified in creq->channels[] */
2822 	creq->n_channels = i;
2823 
2824 	/* translate "Scan for SSID" request */
2825 	if (wreq) {
2826 		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2827 			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2828 				err = -EINVAL;
2829 				goto out;
2830 			}
2831 			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2832 			creq->ssids[0].ssid_len = wreq->essid_len;
2833 		}
2834 		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2835 			creq->n_ssids = 0;
2836 	}
2837 
2838 	for (i = 0; i < NUM_NL80211_BANDS; i++)
2839 		if (wiphy->bands[i])
2840 			creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2841 
2842 	eth_broadcast_addr(creq->bssid);
2843 
2844 	wiphy_lock(&rdev->wiphy);
2845 
2846 	rdev->scan_req = creq;
2847 	err = rdev_scan(rdev, creq);
2848 	if (err) {
2849 		rdev->scan_req = NULL;
2850 		/* creq will be freed below */
2851 	} else {
2852 		nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2853 		/* creq now owned by driver */
2854 		creq = NULL;
2855 		dev_hold(dev);
2856 	}
2857 	wiphy_unlock(&rdev->wiphy);
2858  out:
2859 	kfree(creq);
2860 	return err;
2861 }
2862 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2863 
2864 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2865 				    const struct cfg80211_bss_ies *ies,
2866 				    char *current_ev, char *end_buf)
2867 {
2868 	const u8 *pos, *end, *next;
2869 	struct iw_event iwe;
2870 
2871 	if (!ies)
2872 		return current_ev;
2873 
2874 	/*
2875 	 * If needed, fragment the IEs buffer (at IE boundaries) into short
2876 	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2877 	 */
2878 	pos = ies->data;
2879 	end = pos + ies->len;
2880 
2881 	while (end - pos > IW_GENERIC_IE_MAX) {
2882 		next = pos + 2 + pos[1];
2883 		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2884 			next = next + 2 + next[1];
2885 
2886 		memset(&iwe, 0, sizeof(iwe));
2887 		iwe.cmd = IWEVGENIE;
2888 		iwe.u.data.length = next - pos;
2889 		current_ev = iwe_stream_add_point_check(info, current_ev,
2890 							end_buf, &iwe,
2891 							(void *)pos);
2892 		if (IS_ERR(current_ev))
2893 			return current_ev;
2894 		pos = next;
2895 	}
2896 
2897 	if (end > pos) {
2898 		memset(&iwe, 0, sizeof(iwe));
2899 		iwe.cmd = IWEVGENIE;
2900 		iwe.u.data.length = end - pos;
2901 		current_ev = iwe_stream_add_point_check(info, current_ev,
2902 							end_buf, &iwe,
2903 							(void *)pos);
2904 		if (IS_ERR(current_ev))
2905 			return current_ev;
2906 	}
2907 
2908 	return current_ev;
2909 }
2910 
2911 static char *
2912 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2913 	      struct cfg80211_internal_bss *bss, char *current_ev,
2914 	      char *end_buf)
2915 {
2916 	const struct cfg80211_bss_ies *ies;
2917 	struct iw_event iwe;
2918 	const u8 *ie;
2919 	u8 buf[50];
2920 	u8 *cfg, *p, *tmp;
2921 	int rem, i, sig;
2922 	bool ismesh = false;
2923 
2924 	memset(&iwe, 0, sizeof(iwe));
2925 	iwe.cmd = SIOCGIWAP;
2926 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2927 	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2928 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2929 						IW_EV_ADDR_LEN);
2930 	if (IS_ERR(current_ev))
2931 		return current_ev;
2932 
2933 	memset(&iwe, 0, sizeof(iwe));
2934 	iwe.cmd = SIOCGIWFREQ;
2935 	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2936 	iwe.u.freq.e = 0;
2937 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2938 						IW_EV_FREQ_LEN);
2939 	if (IS_ERR(current_ev))
2940 		return current_ev;
2941 
2942 	memset(&iwe, 0, sizeof(iwe));
2943 	iwe.cmd = SIOCGIWFREQ;
2944 	iwe.u.freq.m = bss->pub.channel->center_freq;
2945 	iwe.u.freq.e = 6;
2946 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2947 						IW_EV_FREQ_LEN);
2948 	if (IS_ERR(current_ev))
2949 		return current_ev;
2950 
2951 	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2952 		memset(&iwe, 0, sizeof(iwe));
2953 		iwe.cmd = IWEVQUAL;
2954 		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2955 				     IW_QUAL_NOISE_INVALID |
2956 				     IW_QUAL_QUAL_UPDATED;
2957 		switch (wiphy->signal_type) {
2958 		case CFG80211_SIGNAL_TYPE_MBM:
2959 			sig = bss->pub.signal / 100;
2960 			iwe.u.qual.level = sig;
2961 			iwe.u.qual.updated |= IW_QUAL_DBM;
2962 			if (sig < -110)		/* rather bad */
2963 				sig = -110;
2964 			else if (sig > -40)	/* perfect */
2965 				sig = -40;
2966 			/* will give a range of 0 .. 70 */
2967 			iwe.u.qual.qual = sig + 110;
2968 			break;
2969 		case CFG80211_SIGNAL_TYPE_UNSPEC:
2970 			iwe.u.qual.level = bss->pub.signal;
2971 			/* will give range 0 .. 100 */
2972 			iwe.u.qual.qual = bss->pub.signal;
2973 			break;
2974 		default:
2975 			/* not reached */
2976 			break;
2977 		}
2978 		current_ev = iwe_stream_add_event_check(info, current_ev,
2979 							end_buf, &iwe,
2980 							IW_EV_QUAL_LEN);
2981 		if (IS_ERR(current_ev))
2982 			return current_ev;
2983 	}
2984 
2985 	memset(&iwe, 0, sizeof(iwe));
2986 	iwe.cmd = SIOCGIWENCODE;
2987 	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
2988 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
2989 	else
2990 		iwe.u.data.flags = IW_ENCODE_DISABLED;
2991 	iwe.u.data.length = 0;
2992 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2993 						&iwe, "");
2994 	if (IS_ERR(current_ev))
2995 		return current_ev;
2996 
2997 	rcu_read_lock();
2998 	ies = rcu_dereference(bss->pub.ies);
2999 	rem = ies->len;
3000 	ie = ies->data;
3001 
3002 	while (rem >= 2) {
3003 		/* invalid data */
3004 		if (ie[1] > rem - 2)
3005 			break;
3006 
3007 		switch (ie[0]) {
3008 		case WLAN_EID_SSID:
3009 			memset(&iwe, 0, sizeof(iwe));
3010 			iwe.cmd = SIOCGIWESSID;
3011 			iwe.u.data.length = ie[1];
3012 			iwe.u.data.flags = 1;
3013 			current_ev = iwe_stream_add_point_check(info,
3014 								current_ev,
3015 								end_buf, &iwe,
3016 								(u8 *)ie + 2);
3017 			if (IS_ERR(current_ev))
3018 				goto unlock;
3019 			break;
3020 		case WLAN_EID_MESH_ID:
3021 			memset(&iwe, 0, sizeof(iwe));
3022 			iwe.cmd = SIOCGIWESSID;
3023 			iwe.u.data.length = ie[1];
3024 			iwe.u.data.flags = 1;
3025 			current_ev = iwe_stream_add_point_check(info,
3026 								current_ev,
3027 								end_buf, &iwe,
3028 								(u8 *)ie + 2);
3029 			if (IS_ERR(current_ev))
3030 				goto unlock;
3031 			break;
3032 		case WLAN_EID_MESH_CONFIG:
3033 			ismesh = true;
3034 			if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
3035 				break;
3036 			cfg = (u8 *)ie + 2;
3037 			memset(&iwe, 0, sizeof(iwe));
3038 			iwe.cmd = IWEVCUSTOM;
3039 			sprintf(buf, "Mesh Network Path Selection Protocol ID: "
3040 				"0x%02X", cfg[0]);
3041 			iwe.u.data.length = strlen(buf);
3042 			current_ev = iwe_stream_add_point_check(info,
3043 								current_ev,
3044 								end_buf,
3045 								&iwe, buf);
3046 			if (IS_ERR(current_ev))
3047 				goto unlock;
3048 			sprintf(buf, "Path Selection Metric ID: 0x%02X",
3049 				cfg[1]);
3050 			iwe.u.data.length = strlen(buf);
3051 			current_ev = iwe_stream_add_point_check(info,
3052 								current_ev,
3053 								end_buf,
3054 								&iwe, buf);
3055 			if (IS_ERR(current_ev))
3056 				goto unlock;
3057 			sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3058 				cfg[2]);
3059 			iwe.u.data.length = strlen(buf);
3060 			current_ev = iwe_stream_add_point_check(info,
3061 								current_ev,
3062 								end_buf,
3063 								&iwe, buf);
3064 			if (IS_ERR(current_ev))
3065 				goto unlock;
3066 			sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3067 			iwe.u.data.length = strlen(buf);
3068 			current_ev = iwe_stream_add_point_check(info,
3069 								current_ev,
3070 								end_buf,
3071 								&iwe, buf);
3072 			if (IS_ERR(current_ev))
3073 				goto unlock;
3074 			sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3075 			iwe.u.data.length = strlen(buf);
3076 			current_ev = iwe_stream_add_point_check(info,
3077 								current_ev,
3078 								end_buf,
3079 								&iwe, buf);
3080 			if (IS_ERR(current_ev))
3081 				goto unlock;
3082 			sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3083 			iwe.u.data.length = strlen(buf);
3084 			current_ev = iwe_stream_add_point_check(info,
3085 								current_ev,
3086 								end_buf,
3087 								&iwe, buf);
3088 			if (IS_ERR(current_ev))
3089 				goto unlock;
3090 			sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3091 			iwe.u.data.length = strlen(buf);
3092 			current_ev = iwe_stream_add_point_check(info,
3093 								current_ev,
3094 								end_buf,
3095 								&iwe, buf);
3096 			if (IS_ERR(current_ev))
3097 				goto unlock;
3098 			break;
3099 		case WLAN_EID_SUPP_RATES:
3100 		case WLAN_EID_EXT_SUPP_RATES:
3101 			/* display all supported rates in readable format */
3102 			p = current_ev + iwe_stream_lcp_len(info);
3103 
3104 			memset(&iwe, 0, sizeof(iwe));
3105 			iwe.cmd = SIOCGIWRATE;
3106 			/* Those two flags are ignored... */
3107 			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3108 
3109 			for (i = 0; i < ie[1]; i++) {
3110 				iwe.u.bitrate.value =
3111 					((ie[i + 2] & 0x7f) * 500000);
3112 				tmp = p;
3113 				p = iwe_stream_add_value(info, current_ev, p,
3114 							 end_buf, &iwe,
3115 							 IW_EV_PARAM_LEN);
3116 				if (p == tmp) {
3117 					current_ev = ERR_PTR(-E2BIG);
3118 					goto unlock;
3119 				}
3120 			}
3121 			current_ev = p;
3122 			break;
3123 		}
3124 		rem -= ie[1] + 2;
3125 		ie += ie[1] + 2;
3126 	}
3127 
3128 	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3129 	    ismesh) {
3130 		memset(&iwe, 0, sizeof(iwe));
3131 		iwe.cmd = SIOCGIWMODE;
3132 		if (ismesh)
3133 			iwe.u.mode = IW_MODE_MESH;
3134 		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3135 			iwe.u.mode = IW_MODE_MASTER;
3136 		else
3137 			iwe.u.mode = IW_MODE_ADHOC;
3138 		current_ev = iwe_stream_add_event_check(info, current_ev,
3139 							end_buf, &iwe,
3140 							IW_EV_UINT_LEN);
3141 		if (IS_ERR(current_ev))
3142 			goto unlock;
3143 	}
3144 
3145 	memset(&iwe, 0, sizeof(iwe));
3146 	iwe.cmd = IWEVCUSTOM;
3147 	sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3148 	iwe.u.data.length = strlen(buf);
3149 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3150 						&iwe, buf);
3151 	if (IS_ERR(current_ev))
3152 		goto unlock;
3153 	memset(&iwe, 0, sizeof(iwe));
3154 	iwe.cmd = IWEVCUSTOM;
3155 	sprintf(buf, " Last beacon: %ums ago",
3156 		elapsed_jiffies_msecs(bss->ts));
3157 	iwe.u.data.length = strlen(buf);
3158 	current_ev = iwe_stream_add_point_check(info, current_ev,
3159 						end_buf, &iwe, buf);
3160 	if (IS_ERR(current_ev))
3161 		goto unlock;
3162 
3163 	current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3164 
3165  unlock:
3166 	rcu_read_unlock();
3167 	return current_ev;
3168 }
3169 
3170 
3171 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3172 				  struct iw_request_info *info,
3173 				  char *buf, size_t len)
3174 {
3175 	char *current_ev = buf;
3176 	char *end_buf = buf + len;
3177 	struct cfg80211_internal_bss *bss;
3178 	int err = 0;
3179 
3180 	spin_lock_bh(&rdev->bss_lock);
3181 	cfg80211_bss_expire(rdev);
3182 
3183 	list_for_each_entry(bss, &rdev->bss_list, list) {
3184 		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3185 			err = -E2BIG;
3186 			break;
3187 		}
3188 		current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3189 					   current_ev, end_buf);
3190 		if (IS_ERR(current_ev)) {
3191 			err = PTR_ERR(current_ev);
3192 			break;
3193 		}
3194 	}
3195 	spin_unlock_bh(&rdev->bss_lock);
3196 
3197 	if (err)
3198 		return err;
3199 	return current_ev - buf;
3200 }
3201 
3202 
3203 int cfg80211_wext_giwscan(struct net_device *dev,
3204 			  struct iw_request_info *info,
3205 			  struct iw_point *data, char *extra)
3206 {
3207 	struct cfg80211_registered_device *rdev;
3208 	int res;
3209 
3210 	if (!netif_running(dev))
3211 		return -ENETDOWN;
3212 
3213 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3214 
3215 	if (IS_ERR(rdev))
3216 		return PTR_ERR(rdev);
3217 
3218 	if (rdev->scan_req || rdev->scan_msg)
3219 		return -EAGAIN;
3220 
3221 	res = ieee80211_scan_results(rdev, info, extra, data->length);
3222 	data->length = 0;
3223 	if (res >= 0) {
3224 		data->length = res;
3225 		res = 0;
3226 	}
3227 
3228 	return res;
3229 }
3230 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3231 #endif
3232