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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) 2018-2024 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  * @psd_20: The 20MHz PSD EIRP of the primary 20MHz channel for the reported AP
100  */
101 struct cfg80211_colocated_ap {
102 	struct list_head list;
103 	u8 bssid[ETH_ALEN];
104 	u8 ssid[IEEE80211_MAX_SSID_LEN];
105 	size_t ssid_len;
106 	u32 short_ssid;
107 	u32 center_freq;
108 	u8 unsolicited_probe:1,
109 	   oct_recommended:1,
110 	   same_ssid:1,
111 	   multi_bss:1,
112 	   transmitted_bssid:1,
113 	   colocated_ess:1,
114 	   short_ssid_valid:1;
115 	s8 psd_20;
116 };
117 
bss_free(struct cfg80211_internal_bss * bss)118 static void bss_free(struct cfg80211_internal_bss *bss)
119 {
120 	struct cfg80211_bss_ies *ies;
121 
122 	if (WARN_ON(atomic_read(&bss->hold)))
123 		return;
124 
125 	ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
126 	if (ies && !bss->pub.hidden_beacon_bss)
127 		kfree_rcu(ies, rcu_head);
128 	ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
129 	if (ies)
130 		kfree_rcu(ies, rcu_head);
131 
132 	/*
133 	 * This happens when the module is removed, it doesn't
134 	 * really matter any more save for completeness
135 	 */
136 	if (!list_empty(&bss->hidden_list))
137 		list_del(&bss->hidden_list);
138 
139 	kfree(bss);
140 }
141 
bss_ref_get(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * bss)142 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
143 			       struct cfg80211_internal_bss *bss)
144 {
145 	lockdep_assert_held(&rdev->bss_lock);
146 
147 	bss->refcount++;
148 
149 	if (bss->pub.hidden_beacon_bss)
150 		bss_from_pub(bss->pub.hidden_beacon_bss)->refcount++;
151 
152 	if (bss->pub.transmitted_bss)
153 		bss_from_pub(bss->pub.transmitted_bss)->refcount++;
154 }
155 
bss_ref_put(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * bss)156 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
157 			       struct cfg80211_internal_bss *bss)
158 {
159 	lockdep_assert_held(&rdev->bss_lock);
160 
161 	if (bss->pub.hidden_beacon_bss) {
162 		struct cfg80211_internal_bss *hbss;
163 
164 		hbss = bss_from_pub(bss->pub.hidden_beacon_bss);
165 		hbss->refcount--;
166 		if (hbss->refcount == 0)
167 			bss_free(hbss);
168 	}
169 
170 	if (bss->pub.transmitted_bss) {
171 		struct cfg80211_internal_bss *tbss;
172 
173 		tbss = bss_from_pub(bss->pub.transmitted_bss);
174 		tbss->refcount--;
175 		if (tbss->refcount == 0)
176 			bss_free(tbss);
177 	}
178 
179 	bss->refcount--;
180 	if (bss->refcount == 0)
181 		bss_free(bss);
182 }
183 
__cfg80211_unlink_bss(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * bss)184 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
185 				  struct cfg80211_internal_bss *bss)
186 {
187 	lockdep_assert_held(&rdev->bss_lock);
188 
189 	if (!list_empty(&bss->hidden_list)) {
190 		/*
191 		 * don't remove the beacon entry if it has
192 		 * probe responses associated with it
193 		 */
194 		if (!bss->pub.hidden_beacon_bss)
195 			return false;
196 		/*
197 		 * if it's a probe response entry break its
198 		 * link to the other entries in the group
199 		 */
200 		list_del_init(&bss->hidden_list);
201 	}
202 
203 	list_del_init(&bss->list);
204 	list_del_init(&bss->pub.nontrans_list);
205 	rb_erase(&bss->rbn, &rdev->bss_tree);
206 	rdev->bss_entries--;
207 	WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
208 		  "rdev bss entries[%d]/list[empty:%d] corruption\n",
209 		  rdev->bss_entries, list_empty(&rdev->bss_list));
210 	bss_ref_put(rdev, bss);
211 	return true;
212 }
213 
cfg80211_is_element_inherited(const struct element * elem,const struct element * non_inherit_elem)214 bool cfg80211_is_element_inherited(const struct element *elem,
215 				   const struct element *non_inherit_elem)
216 {
217 	u8 id_len, ext_id_len, i, loop_len, id;
218 	const u8 *list;
219 
220 	if (elem->id == WLAN_EID_MULTIPLE_BSSID)
221 		return false;
222 
223 	if (elem->id == WLAN_EID_EXTENSION && elem->datalen > 1 &&
224 	    elem->data[0] == WLAN_EID_EXT_EHT_MULTI_LINK)
225 		return false;
226 
227 	if (!non_inherit_elem || non_inherit_elem->datalen < 2)
228 		return true;
229 
230 	/*
231 	 * non inheritance element format is:
232 	 * ext ID (56) | IDs list len | list | extension IDs list len | list
233 	 * Both lists are optional. Both lengths are mandatory.
234 	 * This means valid length is:
235 	 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
236 	 */
237 	id_len = non_inherit_elem->data[1];
238 	if (non_inherit_elem->datalen < 3 + id_len)
239 		return true;
240 
241 	ext_id_len = non_inherit_elem->data[2 + id_len];
242 	if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
243 		return true;
244 
245 	if (elem->id == WLAN_EID_EXTENSION) {
246 		if (!ext_id_len)
247 			return true;
248 		loop_len = ext_id_len;
249 		list = &non_inherit_elem->data[3 + id_len];
250 		id = elem->data[0];
251 	} else {
252 		if (!id_len)
253 			return true;
254 		loop_len = id_len;
255 		list = &non_inherit_elem->data[2];
256 		id = elem->id;
257 	}
258 
259 	for (i = 0; i < loop_len; i++) {
260 		if (list[i] == id)
261 			return false;
262 	}
263 
264 	return true;
265 }
266 EXPORT_SYMBOL(cfg80211_is_element_inherited);
267 
cfg80211_copy_elem_with_frags(const struct element * elem,const u8 * ie,size_t ie_len,u8 ** pos,u8 * buf,size_t buf_len)268 static size_t cfg80211_copy_elem_with_frags(const struct element *elem,
269 					    const u8 *ie, size_t ie_len,
270 					    u8 **pos, u8 *buf, size_t buf_len)
271 {
272 	if (WARN_ON((u8 *)elem < ie || elem->data > ie + ie_len ||
273 		    elem->data + elem->datalen > ie + ie_len))
274 		return 0;
275 
276 	if (elem->datalen + 2 > buf + buf_len - *pos)
277 		return 0;
278 
279 	memcpy(*pos, elem, elem->datalen + 2);
280 	*pos += elem->datalen + 2;
281 
282 	/* Finish if it is not fragmented  */
283 	if (elem->datalen != 255)
284 		return *pos - buf;
285 
286 	ie_len = ie + ie_len - elem->data - elem->datalen;
287 	ie = (const u8 *)elem->data + elem->datalen;
288 
289 	for_each_element(elem, ie, ie_len) {
290 		if (elem->id != WLAN_EID_FRAGMENT)
291 			break;
292 
293 		if (elem->datalen + 2 > buf + buf_len - *pos)
294 			return 0;
295 
296 		memcpy(*pos, elem, elem->datalen + 2);
297 		*pos += elem->datalen + 2;
298 
299 		if (elem->datalen != 255)
300 			break;
301 	}
302 
303 	return *pos - buf;
304 }
305 
cfg80211_gen_new_ie(const u8 * ie,size_t ielen,const u8 * subie,size_t subie_len,u8 * new_ie,size_t new_ie_len)306 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
307 				  const u8 *subie, size_t subie_len,
308 				  u8 *new_ie, size_t new_ie_len)
309 {
310 	const struct element *non_inherit_elem, *parent, *sub;
311 	u8 *pos = new_ie;
312 	u8 id, ext_id;
313 	unsigned int match_len;
314 
315 	non_inherit_elem = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
316 						  subie, subie_len);
317 
318 	/* We copy the elements one by one from the parent to the generated
319 	 * elements.
320 	 * If they are not inherited (included in subie or in the non
321 	 * inheritance element), then we copy all occurrences the first time
322 	 * we see this element type.
323 	 */
324 	for_each_element(parent, ie, ielen) {
325 		if (parent->id == WLAN_EID_FRAGMENT)
326 			continue;
327 
328 		if (parent->id == WLAN_EID_EXTENSION) {
329 			if (parent->datalen < 1)
330 				continue;
331 
332 			id = WLAN_EID_EXTENSION;
333 			ext_id = parent->data[0];
334 			match_len = 1;
335 		} else {
336 			id = parent->id;
337 			match_len = 0;
338 		}
339 
340 		/* Find first occurrence in subie */
341 		sub = cfg80211_find_elem_match(id, subie, subie_len,
342 					       &ext_id, match_len, 0);
343 
344 		/* Copy from parent if not in subie and inherited */
345 		if (!sub &&
346 		    cfg80211_is_element_inherited(parent, non_inherit_elem)) {
347 			if (!cfg80211_copy_elem_with_frags(parent,
348 							   ie, ielen,
349 							   &pos, new_ie,
350 							   new_ie_len))
351 				return 0;
352 
353 			continue;
354 		}
355 
356 		/* Already copied if an earlier element had the same type */
357 		if (cfg80211_find_elem_match(id, ie, (u8 *)parent - ie,
358 					     &ext_id, match_len, 0))
359 			continue;
360 
361 		/* Not inheriting, copy all similar elements from subie */
362 		while (sub) {
363 			if (!cfg80211_copy_elem_with_frags(sub,
364 							   subie, subie_len,
365 							   &pos, new_ie,
366 							   new_ie_len))
367 				return 0;
368 
369 			sub = cfg80211_find_elem_match(id,
370 						       sub->data + sub->datalen,
371 						       subie_len + subie -
372 						       (sub->data +
373 							sub->datalen),
374 						       &ext_id, match_len, 0);
375 		}
376 	}
377 
378 	/* The above misses elements that are included in subie but not in the
379 	 * parent, so do a pass over subie and append those.
380 	 * Skip the non-tx BSSID caps and non-inheritance element.
381 	 */
382 	for_each_element(sub, subie, subie_len) {
383 		if (sub->id == WLAN_EID_NON_TX_BSSID_CAP)
384 			continue;
385 
386 		if (sub->id == WLAN_EID_FRAGMENT)
387 			continue;
388 
389 		if (sub->id == WLAN_EID_EXTENSION) {
390 			if (sub->datalen < 1)
391 				continue;
392 
393 			id = WLAN_EID_EXTENSION;
394 			ext_id = sub->data[0];
395 			match_len = 1;
396 
397 			if (ext_id == WLAN_EID_EXT_NON_INHERITANCE)
398 				continue;
399 		} else {
400 			id = sub->id;
401 			match_len = 0;
402 		}
403 
404 		/* Processed if one was included in the parent */
405 		if (cfg80211_find_elem_match(id, ie, ielen,
406 					     &ext_id, match_len, 0))
407 			continue;
408 
409 		if (!cfg80211_copy_elem_with_frags(sub, subie, subie_len,
410 						   &pos, new_ie, new_ie_len))
411 			return 0;
412 	}
413 
414 	return pos - new_ie;
415 }
416 
is_bss(struct cfg80211_bss * a,const u8 * bssid,const u8 * ssid,size_t ssid_len)417 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
418 		   const u8 *ssid, size_t ssid_len)
419 {
420 	const struct cfg80211_bss_ies *ies;
421 	const struct element *ssid_elem;
422 
423 	if (bssid && !ether_addr_equal(a->bssid, bssid))
424 		return false;
425 
426 	if (!ssid)
427 		return true;
428 
429 	ies = rcu_access_pointer(a->ies);
430 	if (!ies)
431 		return false;
432 	ssid_elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
433 	if (!ssid_elem)
434 		return false;
435 	if (ssid_elem->datalen != ssid_len)
436 		return false;
437 	return memcmp(ssid_elem->data, ssid, ssid_len) == 0;
438 }
439 
440 static int
cfg80211_add_nontrans_list(struct cfg80211_bss * trans_bss,struct cfg80211_bss * nontrans_bss)441 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
442 			   struct cfg80211_bss *nontrans_bss)
443 {
444 	const struct element *ssid_elem;
445 	struct cfg80211_bss *bss = NULL;
446 
447 	rcu_read_lock();
448 	ssid_elem = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
449 	if (!ssid_elem) {
450 		rcu_read_unlock();
451 		return -EINVAL;
452 	}
453 
454 	/* check if nontrans_bss is in the list */
455 	list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
456 		if (is_bss(bss, nontrans_bss->bssid, ssid_elem->data,
457 			   ssid_elem->datalen)) {
458 			rcu_read_unlock();
459 			return 0;
460 		}
461 	}
462 
463 	rcu_read_unlock();
464 
465 	/*
466 	 * This is a bit weird - it's not on the list, but already on another
467 	 * one! The only way that could happen is if there's some BSSID/SSID
468 	 * shared by multiple APs in their multi-BSSID profiles, potentially
469 	 * with hidden SSID mixed in ... ignore it.
470 	 */
471 	if (!list_empty(&nontrans_bss->nontrans_list))
472 		return -EINVAL;
473 
474 	/* add to the list */
475 	list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
476 	return 0;
477 }
478 
__cfg80211_bss_expire(struct cfg80211_registered_device * rdev,unsigned long expire_time)479 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
480 				  unsigned long expire_time)
481 {
482 	struct cfg80211_internal_bss *bss, *tmp;
483 	bool expired = false;
484 
485 	lockdep_assert_held(&rdev->bss_lock);
486 
487 	list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
488 		if (atomic_read(&bss->hold))
489 			continue;
490 		if (!time_after(expire_time, bss->ts))
491 			continue;
492 
493 		if (__cfg80211_unlink_bss(rdev, bss))
494 			expired = true;
495 	}
496 
497 	if (expired)
498 		rdev->bss_generation++;
499 }
500 
cfg80211_bss_expire_oldest(struct cfg80211_registered_device * rdev)501 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
502 {
503 	struct cfg80211_internal_bss *bss, *oldest = NULL;
504 	bool ret;
505 
506 	lockdep_assert_held(&rdev->bss_lock);
507 
508 	list_for_each_entry(bss, &rdev->bss_list, list) {
509 		if (atomic_read(&bss->hold))
510 			continue;
511 
512 		if (!list_empty(&bss->hidden_list) &&
513 		    !bss->pub.hidden_beacon_bss)
514 			continue;
515 
516 		if (oldest && time_before(oldest->ts, bss->ts))
517 			continue;
518 		oldest = bss;
519 	}
520 
521 	if (WARN_ON(!oldest))
522 		return false;
523 
524 	/*
525 	 * The callers make sure to increase rdev->bss_generation if anything
526 	 * gets removed (and a new entry added), so there's no need to also do
527 	 * it here.
528 	 */
529 
530 	ret = __cfg80211_unlink_bss(rdev, oldest);
531 	WARN_ON(!ret);
532 	return ret;
533 }
534 
cfg80211_parse_bss_param(u8 data,struct cfg80211_colocated_ap * coloc_ap)535 static u8 cfg80211_parse_bss_param(u8 data,
536 				   struct cfg80211_colocated_ap *coloc_ap)
537 {
538 	coloc_ap->oct_recommended =
539 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
540 	coloc_ap->same_ssid =
541 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
542 	coloc_ap->multi_bss =
543 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
544 	coloc_ap->transmitted_bssid =
545 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
546 	coloc_ap->unsolicited_probe =
547 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
548 	coloc_ap->colocated_ess =
549 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
550 
551 	return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
552 }
553 
cfg80211_calc_short_ssid(const struct cfg80211_bss_ies * ies,const struct element ** elem,u32 * s_ssid)554 static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
555 				    const struct element **elem, u32 *s_ssid)
556 {
557 
558 	*elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
559 	if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
560 		return -EINVAL;
561 
562 	*s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
563 	return 0;
564 }
565 
cfg80211_free_coloc_ap_list(struct list_head * coloc_ap_list)566 static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
567 {
568 	struct cfg80211_colocated_ap *ap, *tmp_ap;
569 
570 	list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
571 		list_del(&ap->list);
572 		kfree(ap);
573 	}
574 }
575 
cfg80211_parse_ap_info(struct cfg80211_colocated_ap * entry,const u8 * pos,u8 length,const struct element * ssid_elem,u32 s_ssid_tmp)576 static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
577 				  const u8 *pos, u8 length,
578 				  const struct element *ssid_elem,
579 				  u32 s_ssid_tmp)
580 {
581 	u8 bss_params;
582 
583 	entry->psd_20 = IEEE80211_RNR_TBTT_PARAMS_PSD_RESERVED;
584 
585 	/* The length is already verified by the caller to contain bss_params */
586 	if (length > sizeof(struct ieee80211_tbtt_info_7_8_9)) {
587 		struct ieee80211_tbtt_info_ge_11 *tbtt_info = (void *)pos;
588 
589 		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);
590 		entry->short_ssid = le32_to_cpu(tbtt_info->short_ssid);
591 		entry->short_ssid_valid = true;
592 
593 		bss_params = tbtt_info->bss_params;
594 
595 		/* Ignore disabled links */
596 		if (length >= offsetofend(typeof(*tbtt_info), mld_params)) {
597 			if (le16_get_bits(tbtt_info->mld_params.params,
598 					  IEEE80211_RNR_MLD_PARAMS_DISABLED_LINK))
599 				return -EINVAL;
600 		}
601 
602 		if (length >= offsetofend(struct ieee80211_tbtt_info_ge_11,
603 					  psd_20))
604 			entry->psd_20 = tbtt_info->psd_20;
605 	} else {
606 		struct ieee80211_tbtt_info_7_8_9 *tbtt_info = (void *)pos;
607 
608 		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);
609 
610 		bss_params = tbtt_info->bss_params;
611 
612 		if (length == offsetofend(struct ieee80211_tbtt_info_7_8_9,
613 					  psd_20))
614 			entry->psd_20 = tbtt_info->psd_20;
615 	}
616 
617 	/* ignore entries with invalid BSSID */
618 	if (!is_valid_ether_addr(entry->bssid))
619 		return -EINVAL;
620 
621 	/* skip non colocated APs */
622 	if (!cfg80211_parse_bss_param(bss_params, entry))
623 		return -EINVAL;
624 
625 	/* no information about the short ssid. Consider the entry valid
626 	 * for now. It would later be dropped in case there are explicit
627 	 * SSIDs that need to be matched
628 	 */
629 	if (!entry->same_ssid && !entry->short_ssid_valid)
630 		return 0;
631 
632 	if (entry->same_ssid) {
633 		entry->short_ssid = s_ssid_tmp;
634 		entry->short_ssid_valid = true;
635 
636 		/*
637 		 * This is safe because we validate datalen in
638 		 * cfg80211_parse_colocated_ap(), before calling this
639 		 * function.
640 		 */
641 		memcpy(&entry->ssid, &ssid_elem->data, ssid_elem->datalen);
642 		entry->ssid_len = ssid_elem->datalen;
643 	}
644 
645 	return 0;
646 }
647 
648 enum cfg80211_rnr_iter_ret {
649 	RNR_ITER_CONTINUE,
650 	RNR_ITER_BREAK,
651 	RNR_ITER_ERROR,
652 };
653 
654 static bool
cfg80211_iter_rnr(const u8 * elems,size_t elems_len,enum cfg80211_rnr_iter_ret (* iter)(void * data,u8 type,const struct ieee80211_neighbor_ap_info * info,const u8 * tbtt_info,u8 tbtt_info_len),void * iter_data)655 cfg80211_iter_rnr(const u8 *elems, size_t elems_len,
656 		  enum cfg80211_rnr_iter_ret
657 		  (*iter)(void *data, u8 type,
658 			  const struct ieee80211_neighbor_ap_info *info,
659 			  const u8 *tbtt_info, u8 tbtt_info_len),
660 		  void *iter_data)
661 {
662 	const struct element *rnr;
663 	const u8 *pos, *end;
664 
665 	for_each_element_id(rnr, WLAN_EID_REDUCED_NEIGHBOR_REPORT,
666 			    elems, elems_len) {
667 		const struct ieee80211_neighbor_ap_info *info;
668 
669 		pos = rnr->data;
670 		end = rnr->data + rnr->datalen;
671 
672 		/* RNR IE may contain more than one NEIGHBOR_AP_INFO */
673 		while (sizeof(*info) <= end - pos) {
674 			u8 length, i, count;
675 			u8 type;
676 
677 			info = (void *)pos;
678 			count = u8_get_bits(info->tbtt_info_hdr,
679 					    IEEE80211_AP_INFO_TBTT_HDR_COUNT) +
680 				1;
681 			length = info->tbtt_info_len;
682 
683 			pos += sizeof(*info);
684 
685 			if (count * length > end - pos)
686 				return false;
687 
688 			type = u8_get_bits(info->tbtt_info_hdr,
689 					   IEEE80211_AP_INFO_TBTT_HDR_TYPE);
690 
691 			for (i = 0; i < count; i++) {
692 				switch (iter(iter_data, type, info,
693 					     pos, length)) {
694 				case RNR_ITER_CONTINUE:
695 					break;
696 				case RNR_ITER_BREAK:
697 					return true;
698 				case RNR_ITER_ERROR:
699 					return false;
700 				}
701 
702 				pos += length;
703 			}
704 		}
705 
706 		if (pos != end)
707 			return false;
708 	}
709 
710 	return true;
711 }
712 
713 struct colocated_ap_data {
714 	const struct element *ssid_elem;
715 	struct list_head ap_list;
716 	u32 s_ssid_tmp;
717 	int n_coloc;
718 };
719 
720 static enum cfg80211_rnr_iter_ret
cfg80211_parse_colocated_ap_iter(void * _data,u8 type,const struct ieee80211_neighbor_ap_info * info,const u8 * tbtt_info,u8 tbtt_info_len)721 cfg80211_parse_colocated_ap_iter(void *_data, u8 type,
722 				 const struct ieee80211_neighbor_ap_info *info,
723 				 const u8 *tbtt_info, u8 tbtt_info_len)
724 {
725 	struct colocated_ap_data *data = _data;
726 	struct cfg80211_colocated_ap *entry;
727 	enum nl80211_band band;
728 
729 	if (type != IEEE80211_TBTT_INFO_TYPE_TBTT)
730 		return RNR_ITER_CONTINUE;
731 
732 	if (!ieee80211_operating_class_to_band(info->op_class, &band))
733 		return RNR_ITER_CONTINUE;
734 
735 	/* TBTT info must include bss param + BSSID + (short SSID or
736 	 * same_ssid bit to be set). Ignore other options, and move to
737 	 * the next AP info
738 	 */
739 	if (band != NL80211_BAND_6GHZ ||
740 	    !(tbtt_info_len == offsetofend(struct ieee80211_tbtt_info_7_8_9,
741 					   bss_params) ||
742 	      tbtt_info_len == sizeof(struct ieee80211_tbtt_info_7_8_9) ||
743 	      tbtt_info_len >= offsetofend(struct ieee80211_tbtt_info_ge_11,
744 					   bss_params)))
745 		return RNR_ITER_CONTINUE;
746 
747 	entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN, GFP_ATOMIC);
748 	if (!entry)
749 		return RNR_ITER_ERROR;
750 
751 	entry->center_freq =
752 		ieee80211_channel_to_frequency(info->channel, band);
753 
754 	if (!cfg80211_parse_ap_info(entry, tbtt_info, tbtt_info_len,
755 				    data->ssid_elem, data->s_ssid_tmp)) {
756 		data->n_coloc++;
757 		list_add_tail(&entry->list, &data->ap_list);
758 	} else {
759 		kfree(entry);
760 	}
761 
762 	return RNR_ITER_CONTINUE;
763 }
764 
cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies * ies,struct list_head * list)765 static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
766 				       struct list_head *list)
767 {
768 	struct colocated_ap_data data = {};
769 	int ret;
770 
771 	INIT_LIST_HEAD(&data.ap_list);
772 
773 	ret = cfg80211_calc_short_ssid(ies, &data.ssid_elem, &data.s_ssid_tmp);
774 	if (ret)
775 		return 0;
776 
777 	if (!cfg80211_iter_rnr(ies->data, ies->len,
778 			       cfg80211_parse_colocated_ap_iter, &data)) {
779 		cfg80211_free_coloc_ap_list(&data.ap_list);
780 		return 0;
781 	}
782 
783 	list_splice_tail(&data.ap_list, list);
784 	return data.n_coloc;
785 }
786 
cfg80211_scan_req_add_chan(struct cfg80211_scan_request * request,struct ieee80211_channel * chan,bool add_to_6ghz)787 static  void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
788 					struct ieee80211_channel *chan,
789 					bool add_to_6ghz)
790 {
791 	int i;
792 	u32 n_channels = request->n_channels;
793 	struct cfg80211_scan_6ghz_params *params =
794 		&request->scan_6ghz_params[request->n_6ghz_params];
795 
796 	for (i = 0; i < n_channels; i++) {
797 		if (request->channels[i] == chan) {
798 			if (add_to_6ghz)
799 				params->channel_idx = i;
800 			return;
801 		}
802 	}
803 
804 	request->channels[n_channels] = chan;
805 	if (add_to_6ghz)
806 		request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
807 			n_channels;
808 
809 	request->n_channels++;
810 }
811 
cfg80211_find_ssid_match(struct cfg80211_colocated_ap * ap,struct cfg80211_scan_request * request)812 static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
813 				     struct cfg80211_scan_request *request)
814 {
815 	int i;
816 	u32 s_ssid;
817 
818 	for (i = 0; i < request->n_ssids; i++) {
819 		/* wildcard ssid in the scan request */
820 		if (!request->ssids[i].ssid_len) {
821 			if (ap->multi_bss && !ap->transmitted_bssid)
822 				continue;
823 
824 			return true;
825 		}
826 
827 		if (ap->ssid_len &&
828 		    ap->ssid_len == request->ssids[i].ssid_len) {
829 			if (!memcmp(request->ssids[i].ssid, ap->ssid,
830 				    ap->ssid_len))
831 				return true;
832 		} else if (ap->short_ssid_valid) {
833 			s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
834 					   request->ssids[i].ssid_len);
835 
836 			if (ap->short_ssid == s_ssid)
837 				return true;
838 		}
839 	}
840 
841 	return false;
842 }
843 
cfg80211_scan_6ghz(struct cfg80211_registered_device * rdev)844 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
845 {
846 	u8 i;
847 	struct cfg80211_colocated_ap *ap;
848 	int n_channels, count = 0, err;
849 	struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
850 	LIST_HEAD(coloc_ap_list);
851 	bool need_scan_psc = true;
852 	const struct ieee80211_sband_iftype_data *iftd;
853 	size_t size, offs_ssids, offs_6ghz_params, offs_ies;
854 
855 	rdev_req->scan_6ghz = true;
856 
857 	if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
858 		return -EOPNOTSUPP;
859 
860 	iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
861 					       rdev_req->wdev->iftype);
862 	if (!iftd || !iftd->he_cap.has_he)
863 		return -EOPNOTSUPP;
864 
865 	n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
866 
867 	if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
868 		struct cfg80211_internal_bss *intbss;
869 
870 		spin_lock_bh(&rdev->bss_lock);
871 		list_for_each_entry(intbss, &rdev->bss_list, list) {
872 			struct cfg80211_bss *res = &intbss->pub;
873 			const struct cfg80211_bss_ies *ies;
874 			const struct element *ssid_elem;
875 			struct cfg80211_colocated_ap *entry;
876 			u32 s_ssid_tmp;
877 			int ret;
878 
879 			ies = rcu_access_pointer(res->ies);
880 			count += cfg80211_parse_colocated_ap(ies,
881 							     &coloc_ap_list);
882 
883 			/* In case the scan request specified a specific BSSID
884 			 * and the BSS is found and operating on 6GHz band then
885 			 * add this AP to the collocated APs list.
886 			 * This is relevant for ML probe requests when the lower
887 			 * band APs have not been discovered.
888 			 */
889 			if (is_broadcast_ether_addr(rdev_req->bssid) ||
890 			    !ether_addr_equal(rdev_req->bssid, res->bssid) ||
891 			    res->channel->band != NL80211_BAND_6GHZ)
892 				continue;
893 
894 			ret = cfg80211_calc_short_ssid(ies, &ssid_elem,
895 						       &s_ssid_tmp);
896 			if (ret)
897 				continue;
898 
899 			entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
900 					GFP_ATOMIC);
901 
902 			if (!entry)
903 				continue;
904 
905 			memcpy(entry->bssid, res->bssid, ETH_ALEN);
906 			entry->short_ssid = s_ssid_tmp;
907 			memcpy(entry->ssid, ssid_elem->data,
908 			       ssid_elem->datalen);
909 			entry->ssid_len = ssid_elem->datalen;
910 			entry->short_ssid_valid = true;
911 			entry->center_freq = res->channel->center_freq;
912 
913 			list_add_tail(&entry->list, &coloc_ap_list);
914 			count++;
915 		}
916 		spin_unlock_bh(&rdev->bss_lock);
917 	}
918 
919 	size = struct_size(request, channels, n_channels);
920 	offs_ssids = size;
921 	size += sizeof(*request->ssids) * rdev_req->n_ssids;
922 	offs_6ghz_params = size;
923 	size += sizeof(*request->scan_6ghz_params) * count;
924 	offs_ies = size;
925 	size += rdev_req->ie_len;
926 
927 	request = kzalloc(size, GFP_KERNEL);
928 	if (!request) {
929 		cfg80211_free_coloc_ap_list(&coloc_ap_list);
930 		return -ENOMEM;
931 	}
932 
933 	*request = *rdev_req;
934 	request->n_channels = 0;
935 	request->n_6ghz_params = 0;
936 	if (rdev_req->n_ssids) {
937 		/*
938 		 * Add the ssids from the parent scan request to the new
939 		 * scan request, so the driver would be able to use them
940 		 * in its probe requests to discover hidden APs on PSC
941 		 * channels.
942 		 */
943 		request->ssids = (void *)request + offs_ssids;
944 		memcpy(request->ssids, rdev_req->ssids,
945 		       sizeof(*request->ssids) * request->n_ssids);
946 	}
947 	request->scan_6ghz_params = (void *)request + offs_6ghz_params;
948 
949 	if (rdev_req->ie_len) {
950 		void *ie = (void *)request + offs_ies;
951 
952 		memcpy(ie, rdev_req->ie, rdev_req->ie_len);
953 		request->ie = ie;
954 	}
955 
956 	/*
957 	 * PSC channels should not be scanned in case of direct scan with 1 SSID
958 	 * and at least one of the reported co-located APs with same SSID
959 	 * indicating that all APs in the same ESS are co-located
960 	 */
961 	if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
962 		list_for_each_entry(ap, &coloc_ap_list, list) {
963 			if (ap->colocated_ess &&
964 			    cfg80211_find_ssid_match(ap, request)) {
965 				need_scan_psc = false;
966 				break;
967 			}
968 		}
969 	}
970 
971 	/*
972 	 * add to the scan request the channels that need to be scanned
973 	 * regardless of the collocated APs (PSC channels or all channels
974 	 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
975 	 */
976 	for (i = 0; i < rdev_req->n_channels; i++) {
977 		if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
978 		    ((need_scan_psc &&
979 		      cfg80211_channel_is_psc(rdev_req->channels[i])) ||
980 		     !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
981 			cfg80211_scan_req_add_chan(request,
982 						   rdev_req->channels[i],
983 						   false);
984 		}
985 	}
986 
987 	if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
988 		goto skip;
989 
990 	list_for_each_entry(ap, &coloc_ap_list, list) {
991 		bool found = false;
992 		struct cfg80211_scan_6ghz_params *scan_6ghz_params =
993 			&request->scan_6ghz_params[request->n_6ghz_params];
994 		struct ieee80211_channel *chan =
995 			ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
996 
997 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
998 			continue;
999 
1000 		for (i = 0; i < rdev_req->n_channels; i++) {
1001 			if (rdev_req->channels[i] == chan)
1002 				found = true;
1003 		}
1004 
1005 		if (!found)
1006 			continue;
1007 
1008 		if (request->n_ssids > 0 &&
1009 		    !cfg80211_find_ssid_match(ap, request))
1010 			continue;
1011 
1012 		if (!is_broadcast_ether_addr(request->bssid) &&
1013 		    !ether_addr_equal(request->bssid, ap->bssid))
1014 			continue;
1015 
1016 		if (!request->n_ssids && ap->multi_bss && !ap->transmitted_bssid)
1017 			continue;
1018 
1019 		cfg80211_scan_req_add_chan(request, chan, true);
1020 		memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
1021 		scan_6ghz_params->short_ssid = ap->short_ssid;
1022 		scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
1023 		scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
1024 		scan_6ghz_params->psd_20 = ap->psd_20;
1025 
1026 		/*
1027 		 * If a PSC channel is added to the scan and 'need_scan_psc' is
1028 		 * set to false, then all the APs that the scan logic is
1029 		 * interested with on the channel are collocated and thus there
1030 		 * is no need to perform the initial PSC channel listen.
1031 		 */
1032 		if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
1033 			scan_6ghz_params->psc_no_listen = true;
1034 
1035 		request->n_6ghz_params++;
1036 	}
1037 
1038 skip:
1039 	cfg80211_free_coloc_ap_list(&coloc_ap_list);
1040 
1041 	if (request->n_channels) {
1042 		struct cfg80211_scan_request *old = rdev->int_scan_req;
1043 
1044 		rdev->int_scan_req = request;
1045 
1046 		/*
1047 		 * If this scan follows a previous scan, save the scan start
1048 		 * info from the first part of the scan
1049 		 */
1050 		if (old)
1051 			rdev->int_scan_req->info = old->info;
1052 
1053 		err = rdev_scan(rdev, request);
1054 		if (err) {
1055 			rdev->int_scan_req = old;
1056 			kfree(request);
1057 		} else {
1058 			kfree(old);
1059 		}
1060 
1061 		return err;
1062 	}
1063 
1064 	kfree(request);
1065 	return -EINVAL;
1066 }
1067 
cfg80211_scan(struct cfg80211_registered_device * rdev)1068 int cfg80211_scan(struct cfg80211_registered_device *rdev)
1069 {
1070 	struct cfg80211_scan_request *request;
1071 	struct cfg80211_scan_request *rdev_req = rdev->scan_req;
1072 	u32 n_channels = 0, idx, i;
1073 
1074 	if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
1075 		return rdev_scan(rdev, rdev_req);
1076 
1077 	for (i = 0; i < rdev_req->n_channels; i++) {
1078 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
1079 			n_channels++;
1080 	}
1081 
1082 	if (!n_channels)
1083 		return cfg80211_scan_6ghz(rdev);
1084 
1085 	request = kzalloc(struct_size(request, channels, n_channels),
1086 			  GFP_KERNEL);
1087 	if (!request)
1088 		return -ENOMEM;
1089 
1090 	*request = *rdev_req;
1091 	request->n_channels = n_channels;
1092 
1093 	for (i = idx = 0; i < rdev_req->n_channels; i++) {
1094 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
1095 			request->channels[idx++] = rdev_req->channels[i];
1096 	}
1097 
1098 	rdev_req->scan_6ghz = false;
1099 	rdev->int_scan_req = request;
1100 	return rdev_scan(rdev, request);
1101 }
1102 
___cfg80211_scan_done(struct cfg80211_registered_device * rdev,bool send_message)1103 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
1104 			   bool send_message)
1105 {
1106 	struct cfg80211_scan_request *request, *rdev_req;
1107 	struct wireless_dev *wdev;
1108 	struct sk_buff *msg;
1109 #ifdef CONFIG_CFG80211_WEXT
1110 	union iwreq_data wrqu;
1111 #endif
1112 
1113 	lockdep_assert_held(&rdev->wiphy.mtx);
1114 
1115 	if (rdev->scan_msg) {
1116 		nl80211_send_scan_msg(rdev, rdev->scan_msg);
1117 		rdev->scan_msg = NULL;
1118 		return;
1119 	}
1120 
1121 	rdev_req = rdev->scan_req;
1122 	if (!rdev_req)
1123 		return;
1124 
1125 	wdev = rdev_req->wdev;
1126 	request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
1127 
1128 	if (wdev_running(wdev) &&
1129 	    (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
1130 	    !rdev_req->scan_6ghz && !request->info.aborted &&
1131 	    !cfg80211_scan_6ghz(rdev))
1132 		return;
1133 
1134 	/*
1135 	 * This must be before sending the other events!
1136 	 * Otherwise, wpa_supplicant gets completely confused with
1137 	 * wext events.
1138 	 */
1139 	if (wdev->netdev)
1140 		cfg80211_sme_scan_done(wdev->netdev);
1141 
1142 	if (!request->info.aborted &&
1143 	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
1144 		/* flush entries from previous scans */
1145 		spin_lock_bh(&rdev->bss_lock);
1146 		__cfg80211_bss_expire(rdev, request->scan_start);
1147 		spin_unlock_bh(&rdev->bss_lock);
1148 	}
1149 
1150 	msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
1151 
1152 #ifdef CONFIG_CFG80211_WEXT
1153 	if (wdev->netdev && !request->info.aborted) {
1154 		memset(&wrqu, 0, sizeof(wrqu));
1155 
1156 		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
1157 	}
1158 #endif
1159 
1160 	dev_put(wdev->netdev);
1161 
1162 	kfree(rdev->int_scan_req);
1163 	rdev->int_scan_req = NULL;
1164 
1165 	kfree(rdev->scan_req);
1166 	rdev->scan_req = NULL;
1167 
1168 	if (!send_message)
1169 		rdev->scan_msg = msg;
1170 	else
1171 		nl80211_send_scan_msg(rdev, msg);
1172 }
1173 
__cfg80211_scan_done(struct wiphy * wiphy,struct wiphy_work * wk)1174 void __cfg80211_scan_done(struct wiphy *wiphy, struct wiphy_work *wk)
1175 {
1176 	___cfg80211_scan_done(wiphy_to_rdev(wiphy), true);
1177 }
1178 
cfg80211_scan_done(struct cfg80211_scan_request * request,struct cfg80211_scan_info * info)1179 void cfg80211_scan_done(struct cfg80211_scan_request *request,
1180 			struct cfg80211_scan_info *info)
1181 {
1182 	struct cfg80211_scan_info old_info = request->info;
1183 
1184 	trace_cfg80211_scan_done(request, info);
1185 	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1186 		request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1187 
1188 	request->info = *info;
1189 
1190 	/*
1191 	 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1192 	 * be of the first part. In such a case old_info.scan_start_tsf should
1193 	 * be non zero.
1194 	 */
1195 	if (request->scan_6ghz && old_info.scan_start_tsf) {
1196 		request->info.scan_start_tsf = old_info.scan_start_tsf;
1197 		memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1198 		       sizeof(request->info.tsf_bssid));
1199 	}
1200 
1201 	request->notified = true;
1202 	wiphy_work_queue(request->wiphy,
1203 			 &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1204 }
1205 EXPORT_SYMBOL(cfg80211_scan_done);
1206 
cfg80211_add_sched_scan_req(struct cfg80211_registered_device * rdev,struct cfg80211_sched_scan_request * req)1207 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1208 				 struct cfg80211_sched_scan_request *req)
1209 {
1210 	lockdep_assert_held(&rdev->wiphy.mtx);
1211 
1212 	list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1213 }
1214 
cfg80211_del_sched_scan_req(struct cfg80211_registered_device * rdev,struct cfg80211_sched_scan_request * req)1215 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1216 					struct cfg80211_sched_scan_request *req)
1217 {
1218 	lockdep_assert_held(&rdev->wiphy.mtx);
1219 
1220 	list_del_rcu(&req->list);
1221 	kfree_rcu(req, rcu_head);
1222 }
1223 
1224 static struct cfg80211_sched_scan_request *
cfg80211_find_sched_scan_req(struct cfg80211_registered_device * rdev,u64 reqid)1225 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1226 {
1227 	struct cfg80211_sched_scan_request *pos;
1228 
1229 	list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1230 				lockdep_is_held(&rdev->wiphy.mtx)) {
1231 		if (pos->reqid == reqid)
1232 			return pos;
1233 	}
1234 	return NULL;
1235 }
1236 
1237 /*
1238  * Determines if a scheduled scan request can be handled. When a legacy
1239  * scheduled scan is running no other scheduled scan is allowed regardless
1240  * whether the request is for legacy or multi-support scan. When a multi-support
1241  * scheduled scan is running a request for legacy scan is not allowed. In this
1242  * case a request for multi-support scan can be handled if resources are
1243  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1244  */
cfg80211_sched_scan_req_possible(struct cfg80211_registered_device * rdev,bool want_multi)1245 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1246 				     bool want_multi)
1247 {
1248 	struct cfg80211_sched_scan_request *pos;
1249 	int i = 0;
1250 
1251 	list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1252 		/* request id zero means legacy in progress */
1253 		if (!i && !pos->reqid)
1254 			return -EINPROGRESS;
1255 		i++;
1256 	}
1257 
1258 	if (i) {
1259 		/* no legacy allowed when multi request(s) are active */
1260 		if (!want_multi)
1261 			return -EINPROGRESS;
1262 
1263 		/* resource limit reached */
1264 		if (i == rdev->wiphy.max_sched_scan_reqs)
1265 			return -ENOSPC;
1266 	}
1267 	return 0;
1268 }
1269 
cfg80211_sched_scan_results_wk(struct work_struct * work)1270 void cfg80211_sched_scan_results_wk(struct work_struct *work)
1271 {
1272 	struct cfg80211_registered_device *rdev;
1273 	struct cfg80211_sched_scan_request *req, *tmp;
1274 
1275 	rdev = container_of(work, struct cfg80211_registered_device,
1276 			   sched_scan_res_wk);
1277 
1278 	wiphy_lock(&rdev->wiphy);
1279 	list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1280 		if (req->report_results) {
1281 			req->report_results = false;
1282 			if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1283 				/* flush entries from previous scans */
1284 				spin_lock_bh(&rdev->bss_lock);
1285 				__cfg80211_bss_expire(rdev, req->scan_start);
1286 				spin_unlock_bh(&rdev->bss_lock);
1287 				req->scan_start = jiffies;
1288 			}
1289 			nl80211_send_sched_scan(req,
1290 						NL80211_CMD_SCHED_SCAN_RESULTS);
1291 		}
1292 	}
1293 	wiphy_unlock(&rdev->wiphy);
1294 }
1295 
cfg80211_sched_scan_results(struct wiphy * wiphy,u64 reqid)1296 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1297 {
1298 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1299 	struct cfg80211_sched_scan_request *request;
1300 
1301 	trace_cfg80211_sched_scan_results(wiphy, reqid);
1302 	/* ignore if we're not scanning */
1303 
1304 	rcu_read_lock();
1305 	request = cfg80211_find_sched_scan_req(rdev, reqid);
1306 	if (request) {
1307 		request->report_results = true;
1308 		queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1309 	}
1310 	rcu_read_unlock();
1311 }
1312 EXPORT_SYMBOL(cfg80211_sched_scan_results);
1313 
cfg80211_sched_scan_stopped_locked(struct wiphy * wiphy,u64 reqid)1314 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1315 {
1316 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1317 
1318 	lockdep_assert_held(&wiphy->mtx);
1319 
1320 	trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1321 
1322 	__cfg80211_stop_sched_scan(rdev, reqid, true);
1323 }
1324 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1325 
cfg80211_sched_scan_stopped(struct wiphy * wiphy,u64 reqid)1326 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1327 {
1328 	wiphy_lock(wiphy);
1329 	cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1330 	wiphy_unlock(wiphy);
1331 }
1332 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1333 
cfg80211_stop_sched_scan_req(struct cfg80211_registered_device * rdev,struct cfg80211_sched_scan_request * req,bool driver_initiated)1334 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1335 				 struct cfg80211_sched_scan_request *req,
1336 				 bool driver_initiated)
1337 {
1338 	lockdep_assert_held(&rdev->wiphy.mtx);
1339 
1340 	if (!driver_initiated) {
1341 		int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1342 		if (err)
1343 			return err;
1344 	}
1345 
1346 	nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1347 
1348 	cfg80211_del_sched_scan_req(rdev, req);
1349 
1350 	return 0;
1351 }
1352 
__cfg80211_stop_sched_scan(struct cfg80211_registered_device * rdev,u64 reqid,bool driver_initiated)1353 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1354 			       u64 reqid, bool driver_initiated)
1355 {
1356 	struct cfg80211_sched_scan_request *sched_scan_req;
1357 
1358 	lockdep_assert_held(&rdev->wiphy.mtx);
1359 
1360 	sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1361 	if (!sched_scan_req)
1362 		return -ENOENT;
1363 
1364 	return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1365 					    driver_initiated);
1366 }
1367 
cfg80211_bss_age(struct cfg80211_registered_device * rdev,unsigned long age_secs)1368 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1369                       unsigned long age_secs)
1370 {
1371 	struct cfg80211_internal_bss *bss;
1372 	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1373 
1374 	spin_lock_bh(&rdev->bss_lock);
1375 	list_for_each_entry(bss, &rdev->bss_list, list)
1376 		bss->ts -= age_jiffies;
1377 	spin_unlock_bh(&rdev->bss_lock);
1378 }
1379 
cfg80211_bss_expire(struct cfg80211_registered_device * rdev)1380 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1381 {
1382 	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1383 }
1384 
cfg80211_bss_flush(struct wiphy * wiphy)1385 void cfg80211_bss_flush(struct wiphy *wiphy)
1386 {
1387 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1388 
1389 	spin_lock_bh(&rdev->bss_lock);
1390 	__cfg80211_bss_expire(rdev, jiffies);
1391 	spin_unlock_bh(&rdev->bss_lock);
1392 }
1393 EXPORT_SYMBOL(cfg80211_bss_flush);
1394 
1395 const struct element *
cfg80211_find_elem_match(u8 eid,const u8 * ies,unsigned int len,const u8 * match,unsigned int match_len,unsigned int match_offset)1396 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1397 			 const u8 *match, unsigned int match_len,
1398 			 unsigned int match_offset)
1399 {
1400 	const struct element *elem;
1401 
1402 	for_each_element_id(elem, eid, ies, len) {
1403 		if (elem->datalen >= match_offset + match_len &&
1404 		    !memcmp(elem->data + match_offset, match, match_len))
1405 			return elem;
1406 	}
1407 
1408 	return NULL;
1409 }
1410 EXPORT_SYMBOL(cfg80211_find_elem_match);
1411 
cfg80211_find_vendor_elem(unsigned int oui,int oui_type,const u8 * ies,unsigned int len)1412 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1413 						const u8 *ies,
1414 						unsigned int len)
1415 {
1416 	const struct element *elem;
1417 	u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1418 	int match_len = (oui_type < 0) ? 3 : sizeof(match);
1419 
1420 	if (WARN_ON(oui_type > 0xff))
1421 		return NULL;
1422 
1423 	elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1424 					match, match_len, 0);
1425 
1426 	if (!elem || elem->datalen < 4)
1427 		return NULL;
1428 
1429 	return elem;
1430 }
1431 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1432 
1433 /**
1434  * enum bss_compare_mode - BSS compare mode
1435  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1436  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1437  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1438  */
1439 enum bss_compare_mode {
1440 	BSS_CMP_REGULAR,
1441 	BSS_CMP_HIDE_ZLEN,
1442 	BSS_CMP_HIDE_NUL,
1443 };
1444 
cmp_bss(struct cfg80211_bss * a,struct cfg80211_bss * b,enum bss_compare_mode mode)1445 static int cmp_bss(struct cfg80211_bss *a,
1446 		   struct cfg80211_bss *b,
1447 		   enum bss_compare_mode mode)
1448 {
1449 	const struct cfg80211_bss_ies *a_ies, *b_ies;
1450 	const u8 *ie1 = NULL;
1451 	const u8 *ie2 = NULL;
1452 	int i, r;
1453 
1454 	if (a->channel != b->channel)
1455 		return (b->channel->center_freq * 1000 + b->channel->freq_offset) -
1456 		       (a->channel->center_freq * 1000 + a->channel->freq_offset);
1457 
1458 	a_ies = rcu_access_pointer(a->ies);
1459 	if (!a_ies)
1460 		return -1;
1461 	b_ies = rcu_access_pointer(b->ies);
1462 	if (!b_ies)
1463 		return 1;
1464 
1465 	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1466 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1467 				       a_ies->data, a_ies->len);
1468 	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1469 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1470 				       b_ies->data, b_ies->len);
1471 	if (ie1 && ie2) {
1472 		int mesh_id_cmp;
1473 
1474 		if (ie1[1] == ie2[1])
1475 			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1476 		else
1477 			mesh_id_cmp = ie2[1] - ie1[1];
1478 
1479 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1480 				       a_ies->data, a_ies->len);
1481 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1482 				       b_ies->data, b_ies->len);
1483 		if (ie1 && ie2) {
1484 			if (mesh_id_cmp)
1485 				return mesh_id_cmp;
1486 			if (ie1[1] != ie2[1])
1487 				return ie2[1] - ie1[1];
1488 			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1489 		}
1490 	}
1491 
1492 	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1493 	if (r)
1494 		return r;
1495 
1496 	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1497 	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1498 
1499 	if (!ie1 && !ie2)
1500 		return 0;
1501 
1502 	/*
1503 	 * Note that with "hide_ssid", the function returns a match if
1504 	 * the already-present BSS ("b") is a hidden SSID beacon for
1505 	 * the new BSS ("a").
1506 	 */
1507 
1508 	/* sort missing IE before (left of) present IE */
1509 	if (!ie1)
1510 		return -1;
1511 	if (!ie2)
1512 		return 1;
1513 
1514 	switch (mode) {
1515 	case BSS_CMP_HIDE_ZLEN:
1516 		/*
1517 		 * In ZLEN mode we assume the BSS entry we're
1518 		 * looking for has a zero-length SSID. So if
1519 		 * the one we're looking at right now has that,
1520 		 * return 0. Otherwise, return the difference
1521 		 * in length, but since we're looking for the
1522 		 * 0-length it's really equivalent to returning
1523 		 * the length of the one we're looking at.
1524 		 *
1525 		 * No content comparison is needed as we assume
1526 		 * the content length is zero.
1527 		 */
1528 		return ie2[1];
1529 	case BSS_CMP_REGULAR:
1530 	default:
1531 		/* sort by length first, then by contents */
1532 		if (ie1[1] != ie2[1])
1533 			return ie2[1] - ie1[1];
1534 		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1535 	case BSS_CMP_HIDE_NUL:
1536 		if (ie1[1] != ie2[1])
1537 			return ie2[1] - ie1[1];
1538 		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1539 		for (i = 0; i < ie2[1]; i++)
1540 			if (ie2[i + 2])
1541 				return -1;
1542 		return 0;
1543 	}
1544 }
1545 
cfg80211_bss_type_match(u16 capability,enum nl80211_band band,enum ieee80211_bss_type bss_type)1546 static bool cfg80211_bss_type_match(u16 capability,
1547 				    enum nl80211_band band,
1548 				    enum ieee80211_bss_type bss_type)
1549 {
1550 	bool ret = true;
1551 	u16 mask, val;
1552 
1553 	if (bss_type == IEEE80211_BSS_TYPE_ANY)
1554 		return ret;
1555 
1556 	if (band == NL80211_BAND_60GHZ) {
1557 		mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1558 		switch (bss_type) {
1559 		case IEEE80211_BSS_TYPE_ESS:
1560 			val = WLAN_CAPABILITY_DMG_TYPE_AP;
1561 			break;
1562 		case IEEE80211_BSS_TYPE_PBSS:
1563 			val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1564 			break;
1565 		case IEEE80211_BSS_TYPE_IBSS:
1566 			val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1567 			break;
1568 		default:
1569 			return false;
1570 		}
1571 	} else {
1572 		mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1573 		switch (bss_type) {
1574 		case IEEE80211_BSS_TYPE_ESS:
1575 			val = WLAN_CAPABILITY_ESS;
1576 			break;
1577 		case IEEE80211_BSS_TYPE_IBSS:
1578 			val = WLAN_CAPABILITY_IBSS;
1579 			break;
1580 		case IEEE80211_BSS_TYPE_MBSS:
1581 			val = 0;
1582 			break;
1583 		default:
1584 			return false;
1585 		}
1586 	}
1587 
1588 	ret = ((capability & mask) == val);
1589 	return ret;
1590 }
1591 
1592 /* Returned bss is reference counted and must be cleaned up appropriately. */
__cfg80211_get_bss(struct wiphy * wiphy,struct ieee80211_channel * channel,const u8 * bssid,const u8 * ssid,size_t ssid_len,enum ieee80211_bss_type bss_type,enum ieee80211_privacy privacy,u32 use_for)1593 struct cfg80211_bss *__cfg80211_get_bss(struct wiphy *wiphy,
1594 					struct ieee80211_channel *channel,
1595 					const u8 *bssid,
1596 					const u8 *ssid, size_t ssid_len,
1597 					enum ieee80211_bss_type bss_type,
1598 					enum ieee80211_privacy privacy,
1599 					u32 use_for)
1600 {
1601 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1602 	struct cfg80211_internal_bss *bss, *res = NULL;
1603 	unsigned long now = jiffies;
1604 	int bss_privacy;
1605 
1606 	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1607 			       privacy);
1608 
1609 	spin_lock_bh(&rdev->bss_lock);
1610 
1611 	list_for_each_entry(bss, &rdev->bss_list, list) {
1612 		if (!cfg80211_bss_type_match(bss->pub.capability,
1613 					     bss->pub.channel->band, bss_type))
1614 			continue;
1615 
1616 		bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1617 		if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1618 		    (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1619 			continue;
1620 		if (channel && bss->pub.channel != channel)
1621 			continue;
1622 		if (!is_valid_ether_addr(bss->pub.bssid))
1623 			continue;
1624 		if ((bss->pub.use_for & use_for) != use_for)
1625 			continue;
1626 		/* Don't get expired BSS structs */
1627 		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1628 		    !atomic_read(&bss->hold))
1629 			continue;
1630 		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1631 			res = bss;
1632 			bss_ref_get(rdev, res);
1633 			break;
1634 		}
1635 	}
1636 
1637 	spin_unlock_bh(&rdev->bss_lock);
1638 	if (!res)
1639 		return NULL;
1640 	trace_cfg80211_return_bss(&res->pub);
1641 	return &res->pub;
1642 }
1643 EXPORT_SYMBOL(__cfg80211_get_bss);
1644 
rb_insert_bss(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * bss)1645 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1646 			  struct cfg80211_internal_bss *bss)
1647 {
1648 	struct rb_node **p = &rdev->bss_tree.rb_node;
1649 	struct rb_node *parent = NULL;
1650 	struct cfg80211_internal_bss *tbss;
1651 	int cmp;
1652 
1653 	while (*p) {
1654 		parent = *p;
1655 		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1656 
1657 		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1658 
1659 		if (WARN_ON(!cmp)) {
1660 			/* will sort of leak this BSS */
1661 			return;
1662 		}
1663 
1664 		if (cmp < 0)
1665 			p = &(*p)->rb_left;
1666 		else
1667 			p = &(*p)->rb_right;
1668 	}
1669 
1670 	rb_link_node(&bss->rbn, parent, p);
1671 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
1672 }
1673 
1674 static struct cfg80211_internal_bss *
rb_find_bss(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * res,enum bss_compare_mode mode)1675 rb_find_bss(struct cfg80211_registered_device *rdev,
1676 	    struct cfg80211_internal_bss *res,
1677 	    enum bss_compare_mode mode)
1678 {
1679 	struct rb_node *n = rdev->bss_tree.rb_node;
1680 	struct cfg80211_internal_bss *bss;
1681 	int r;
1682 
1683 	while (n) {
1684 		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1685 		r = cmp_bss(&res->pub, &bss->pub, mode);
1686 
1687 		if (r == 0)
1688 			return bss;
1689 		else if (r < 0)
1690 			n = n->rb_left;
1691 		else
1692 			n = n->rb_right;
1693 	}
1694 
1695 	return NULL;
1696 }
1697 
cfg80211_combine_bsses(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * new)1698 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1699 				   struct cfg80211_internal_bss *new)
1700 {
1701 	const struct cfg80211_bss_ies *ies;
1702 	struct cfg80211_internal_bss *bss;
1703 	const u8 *ie;
1704 	int i, ssidlen;
1705 	u8 fold = 0;
1706 	u32 n_entries = 0;
1707 
1708 	ies = rcu_access_pointer(new->pub.beacon_ies);
1709 	if (WARN_ON(!ies))
1710 		return false;
1711 
1712 	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1713 	if (!ie) {
1714 		/* nothing to do */
1715 		return true;
1716 	}
1717 
1718 	ssidlen = ie[1];
1719 	for (i = 0; i < ssidlen; i++)
1720 		fold |= ie[2 + i];
1721 
1722 	if (fold) {
1723 		/* not a hidden SSID */
1724 		return true;
1725 	}
1726 
1727 	/* This is the bad part ... */
1728 
1729 	list_for_each_entry(bss, &rdev->bss_list, list) {
1730 		/*
1731 		 * we're iterating all the entries anyway, so take the
1732 		 * opportunity to validate the list length accounting
1733 		 */
1734 		n_entries++;
1735 
1736 		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1737 			continue;
1738 		if (bss->pub.channel != new->pub.channel)
1739 			continue;
1740 		if (rcu_access_pointer(bss->pub.beacon_ies))
1741 			continue;
1742 		ies = rcu_access_pointer(bss->pub.ies);
1743 		if (!ies)
1744 			continue;
1745 		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1746 		if (!ie)
1747 			continue;
1748 		if (ssidlen && ie[1] != ssidlen)
1749 			continue;
1750 		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1751 			continue;
1752 		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1753 			list_del(&bss->hidden_list);
1754 		/* combine them */
1755 		list_add(&bss->hidden_list, &new->hidden_list);
1756 		bss->pub.hidden_beacon_bss = &new->pub;
1757 		new->refcount += bss->refcount;
1758 		rcu_assign_pointer(bss->pub.beacon_ies,
1759 				   new->pub.beacon_ies);
1760 	}
1761 
1762 	WARN_ONCE(n_entries != rdev->bss_entries,
1763 		  "rdev bss entries[%d]/list[len:%d] corruption\n",
1764 		  rdev->bss_entries, n_entries);
1765 
1766 	return true;
1767 }
1768 
cfg80211_update_hidden_bsses(struct cfg80211_internal_bss * known,const struct cfg80211_bss_ies * new_ies,const struct cfg80211_bss_ies * old_ies)1769 static void cfg80211_update_hidden_bsses(struct cfg80211_internal_bss *known,
1770 					 const struct cfg80211_bss_ies *new_ies,
1771 					 const struct cfg80211_bss_ies *old_ies)
1772 {
1773 	struct cfg80211_internal_bss *bss;
1774 
1775 	/* Assign beacon IEs to all sub entries */
1776 	list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1777 		const struct cfg80211_bss_ies *ies;
1778 
1779 		ies = rcu_access_pointer(bss->pub.beacon_ies);
1780 		WARN_ON(ies != old_ies);
1781 
1782 		rcu_assign_pointer(bss->pub.beacon_ies, new_ies);
1783 	}
1784 }
1785 
1786 static bool
cfg80211_update_known_bss(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * known,struct cfg80211_internal_bss * new,bool signal_valid)1787 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1788 			  struct cfg80211_internal_bss *known,
1789 			  struct cfg80211_internal_bss *new,
1790 			  bool signal_valid)
1791 {
1792 	lockdep_assert_held(&rdev->bss_lock);
1793 
1794 	/* Update IEs */
1795 	if (rcu_access_pointer(new->pub.proberesp_ies)) {
1796 		const struct cfg80211_bss_ies *old;
1797 
1798 		old = rcu_access_pointer(known->pub.proberesp_ies);
1799 
1800 		rcu_assign_pointer(known->pub.proberesp_ies,
1801 				   new->pub.proberesp_ies);
1802 		/* Override possible earlier Beacon frame IEs */
1803 		rcu_assign_pointer(known->pub.ies,
1804 				   new->pub.proberesp_ies);
1805 		if (old)
1806 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1807 	}
1808 
1809 	if (rcu_access_pointer(new->pub.beacon_ies)) {
1810 		const struct cfg80211_bss_ies *old;
1811 
1812 		if (known->pub.hidden_beacon_bss &&
1813 		    !list_empty(&known->hidden_list)) {
1814 			const struct cfg80211_bss_ies *f;
1815 
1816 			/* The known BSS struct is one of the probe
1817 			 * response members of a group, but we're
1818 			 * receiving a beacon (beacon_ies in the new
1819 			 * bss is used). This can only mean that the
1820 			 * AP changed its beacon from not having an
1821 			 * SSID to showing it, which is confusing so
1822 			 * drop this information.
1823 			 */
1824 
1825 			f = rcu_access_pointer(new->pub.beacon_ies);
1826 			kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1827 			return false;
1828 		}
1829 
1830 		old = rcu_access_pointer(known->pub.beacon_ies);
1831 
1832 		rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1833 
1834 		/* Override IEs if they were from a beacon before */
1835 		if (old == rcu_access_pointer(known->pub.ies))
1836 			rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1837 
1838 		cfg80211_update_hidden_bsses(known,
1839 					     rcu_access_pointer(new->pub.beacon_ies),
1840 					     old);
1841 
1842 		if (old)
1843 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1844 	}
1845 
1846 	known->pub.beacon_interval = new->pub.beacon_interval;
1847 
1848 	/* don't update the signal if beacon was heard on
1849 	 * adjacent channel.
1850 	 */
1851 	if (signal_valid)
1852 		known->pub.signal = new->pub.signal;
1853 	known->pub.capability = new->pub.capability;
1854 	known->ts = new->ts;
1855 	known->ts_boottime = new->ts_boottime;
1856 	known->parent_tsf = new->parent_tsf;
1857 	known->pub.chains = new->pub.chains;
1858 	memcpy(known->pub.chain_signal, new->pub.chain_signal,
1859 	       IEEE80211_MAX_CHAINS);
1860 	ether_addr_copy(known->parent_bssid, new->parent_bssid);
1861 	known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1862 	known->pub.bssid_index = new->pub.bssid_index;
1863 	known->pub.use_for &= new->pub.use_for;
1864 	known->pub.cannot_use_reasons = new->pub.cannot_use_reasons;
1865 
1866 	return true;
1867 }
1868 
1869 /* Returned bss is reference counted and must be cleaned up appropriately. */
1870 static struct cfg80211_internal_bss *
__cfg80211_bss_update(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * tmp,bool signal_valid,unsigned long ts)1871 __cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1872 		      struct cfg80211_internal_bss *tmp,
1873 		      bool signal_valid, unsigned long ts)
1874 {
1875 	struct cfg80211_internal_bss *found = NULL;
1876 	struct cfg80211_bss_ies *ies;
1877 
1878 	if (WARN_ON(!tmp->pub.channel))
1879 		goto free_ies;
1880 
1881 	tmp->ts = ts;
1882 
1883 	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies)))
1884 		goto free_ies;
1885 
1886 	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1887 
1888 	if (found) {
1889 		if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1890 			return NULL;
1891 	} else {
1892 		struct cfg80211_internal_bss *new;
1893 		struct cfg80211_internal_bss *hidden;
1894 
1895 		/*
1896 		 * create a copy -- the "res" variable that is passed in
1897 		 * is allocated on the stack since it's not needed in the
1898 		 * more common case of an update
1899 		 */
1900 		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1901 			      GFP_ATOMIC);
1902 		if (!new)
1903 			goto free_ies;
1904 		memcpy(new, tmp, sizeof(*new));
1905 		new->refcount = 1;
1906 		INIT_LIST_HEAD(&new->hidden_list);
1907 		INIT_LIST_HEAD(&new->pub.nontrans_list);
1908 		/* we'll set this later if it was non-NULL */
1909 		new->pub.transmitted_bss = NULL;
1910 
1911 		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1912 			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1913 			if (!hidden)
1914 				hidden = rb_find_bss(rdev, tmp,
1915 						     BSS_CMP_HIDE_NUL);
1916 			if (hidden) {
1917 				new->pub.hidden_beacon_bss = &hidden->pub;
1918 				list_add(&new->hidden_list,
1919 					 &hidden->hidden_list);
1920 				hidden->refcount++;
1921 
1922 				ies = (void *)rcu_access_pointer(new->pub.beacon_ies);
1923 				rcu_assign_pointer(new->pub.beacon_ies,
1924 						   hidden->pub.beacon_ies);
1925 				if (ies)
1926 					kfree_rcu(ies, rcu_head);
1927 			}
1928 		} else {
1929 			/*
1930 			 * Ok so we found a beacon, and don't have an entry. If
1931 			 * it's a beacon with hidden SSID, we might be in for an
1932 			 * expensive search for any probe responses that should
1933 			 * be grouped with this beacon for updates ...
1934 			 */
1935 			if (!cfg80211_combine_bsses(rdev, new)) {
1936 				bss_ref_put(rdev, new);
1937 				return NULL;
1938 			}
1939 		}
1940 
1941 		if (rdev->bss_entries >= bss_entries_limit &&
1942 		    !cfg80211_bss_expire_oldest(rdev)) {
1943 			bss_ref_put(rdev, new);
1944 			return NULL;
1945 		}
1946 
1947 		/* This must be before the call to bss_ref_get */
1948 		if (tmp->pub.transmitted_bss) {
1949 			new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1950 			bss_ref_get(rdev, bss_from_pub(tmp->pub.transmitted_bss));
1951 		}
1952 
1953 		list_add_tail(&new->list, &rdev->bss_list);
1954 		rdev->bss_entries++;
1955 		rb_insert_bss(rdev, new);
1956 		found = new;
1957 	}
1958 
1959 	rdev->bss_generation++;
1960 	bss_ref_get(rdev, found);
1961 
1962 	return found;
1963 
1964 free_ies:
1965 	ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1966 	if (ies)
1967 		kfree_rcu(ies, rcu_head);
1968 	ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1969 	if (ies)
1970 		kfree_rcu(ies, rcu_head);
1971 
1972 	return NULL;
1973 }
1974 
1975 struct cfg80211_internal_bss *
cfg80211_bss_update(struct cfg80211_registered_device * rdev,struct cfg80211_internal_bss * tmp,bool signal_valid,unsigned long ts)1976 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1977 		    struct cfg80211_internal_bss *tmp,
1978 		    bool signal_valid, unsigned long ts)
1979 {
1980 	struct cfg80211_internal_bss *res;
1981 
1982 	spin_lock_bh(&rdev->bss_lock);
1983 	res = __cfg80211_bss_update(rdev, tmp, signal_valid, ts);
1984 	spin_unlock_bh(&rdev->bss_lock);
1985 
1986 	return res;
1987 }
1988 
cfg80211_get_ies_channel_number(const u8 * ie,size_t ielen,enum nl80211_band band)1989 int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen,
1990 				    enum nl80211_band band)
1991 {
1992 	const struct element *tmp;
1993 
1994 	if (band == NL80211_BAND_6GHZ) {
1995 		struct ieee80211_he_operation *he_oper;
1996 
1997 		tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie,
1998 					     ielen);
1999 		if (tmp && tmp->datalen >= sizeof(*he_oper) &&
2000 		    tmp->datalen >= ieee80211_he_oper_size(&tmp->data[1])) {
2001 			const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
2002 
2003 			he_oper = (void *)&tmp->data[1];
2004 
2005 			he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
2006 			if (!he_6ghz_oper)
2007 				return -1;
2008 
2009 			return he_6ghz_oper->primary;
2010 		}
2011 	} else if (band == NL80211_BAND_S1GHZ) {
2012 		tmp = cfg80211_find_elem(WLAN_EID_S1G_OPERATION, ie, ielen);
2013 		if (tmp && tmp->datalen >= sizeof(struct ieee80211_s1g_oper_ie)) {
2014 			struct ieee80211_s1g_oper_ie *s1gop = (void *)tmp->data;
2015 
2016 			return s1gop->oper_ch;
2017 		}
2018 	} else {
2019 		tmp = cfg80211_find_elem(WLAN_EID_DS_PARAMS, ie, ielen);
2020 		if (tmp && tmp->datalen == 1)
2021 			return tmp->data[0];
2022 
2023 		tmp = cfg80211_find_elem(WLAN_EID_HT_OPERATION, ie, ielen);
2024 		if (tmp &&
2025 		    tmp->datalen >= sizeof(struct ieee80211_ht_operation)) {
2026 			struct ieee80211_ht_operation *htop = (void *)tmp->data;
2027 
2028 			return htop->primary_chan;
2029 		}
2030 	}
2031 
2032 	return -1;
2033 }
2034 EXPORT_SYMBOL(cfg80211_get_ies_channel_number);
2035 
2036 /*
2037  * Update RX channel information based on the available frame payload
2038  * information. This is mainly for the 2.4 GHz band where frames can be received
2039  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
2040  * element to indicate the current (transmitting) channel, but this might also
2041  * be needed on other bands if RX frequency does not match with the actual
2042  * operating channel of a BSS, or if the AP reports a different primary channel.
2043  */
2044 static struct ieee80211_channel *
cfg80211_get_bss_channel(struct wiphy * wiphy,const u8 * ie,size_t ielen,struct ieee80211_channel * channel)2045 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
2046 			 struct ieee80211_channel *channel)
2047 {
2048 	u32 freq;
2049 	int channel_number;
2050 	struct ieee80211_channel *alt_channel;
2051 
2052 	channel_number = cfg80211_get_ies_channel_number(ie, ielen,
2053 							 channel->band);
2054 
2055 	if (channel_number < 0) {
2056 		/* No channel information in frame payload */
2057 		return channel;
2058 	}
2059 
2060 	freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
2061 
2062 	/*
2063 	 * Frame info (beacon/prob res) is the same as received channel,
2064 	 * no need for further processing.
2065 	 */
2066 	if (freq == ieee80211_channel_to_khz(channel))
2067 		return channel;
2068 
2069 	alt_channel = ieee80211_get_channel_khz(wiphy, freq);
2070 	if (!alt_channel) {
2071 		if (channel->band == NL80211_BAND_2GHZ ||
2072 		    channel->band == NL80211_BAND_6GHZ) {
2073 			/*
2074 			 * Better not allow unexpected channels when that could
2075 			 * be going beyond the 1-11 range (e.g., discovering
2076 			 * BSS on channel 12 when radio is configured for
2077 			 * channel 11) or beyond the 6 GHz channel range.
2078 			 */
2079 			return NULL;
2080 		}
2081 
2082 		/* No match for the payload channel number - ignore it */
2083 		return channel;
2084 	}
2085 
2086 	/*
2087 	 * Use the channel determined through the payload channel number
2088 	 * instead of the RX channel reported by the driver.
2089 	 */
2090 	if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
2091 		return NULL;
2092 	return alt_channel;
2093 }
2094 
2095 struct cfg80211_inform_single_bss_data {
2096 	struct cfg80211_inform_bss *drv_data;
2097 	enum cfg80211_bss_frame_type ftype;
2098 	struct ieee80211_channel *channel;
2099 	u8 bssid[ETH_ALEN];
2100 	u64 tsf;
2101 	u16 capability;
2102 	u16 beacon_interval;
2103 	const u8 *ie;
2104 	size_t ielen;
2105 
2106 	enum {
2107 		BSS_SOURCE_DIRECT = 0,
2108 		BSS_SOURCE_MBSSID,
2109 		BSS_SOURCE_STA_PROFILE,
2110 	} bss_source;
2111 	/* Set if reporting bss_source != BSS_SOURCE_DIRECT */
2112 	struct cfg80211_bss *source_bss;
2113 	u8 max_bssid_indicator;
2114 	u8 bssid_index;
2115 
2116 	u8 use_for;
2117 	u64 cannot_use_reasons;
2118 };
2119 
cfg80211_6ghz_power_type_valid(const u8 * ie,size_t ielen,const u32 flags)2120 static bool cfg80211_6ghz_power_type_valid(const u8 *ie, size_t ielen,
2121 					   const u32 flags)
2122 {
2123 	const struct element *tmp;
2124 	struct ieee80211_he_operation *he_oper;
2125 
2126 	tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie, ielen);
2127 	if (tmp && tmp->datalen >= sizeof(*he_oper) + 1) {
2128 		const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
2129 
2130 		he_oper = (void *)&tmp->data[1];
2131 		he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
2132 
2133 		if (!he_6ghz_oper)
2134 			return false;
2135 
2136 		switch (u8_get_bits(he_6ghz_oper->control,
2137 				    IEEE80211_HE_6GHZ_OPER_CTRL_REG_INFO)) {
2138 		case IEEE80211_6GHZ_CTRL_REG_LPI_AP:
2139 			return true;
2140 		case IEEE80211_6GHZ_CTRL_REG_SP_AP:
2141 			return !(flags & IEEE80211_CHAN_NO_6GHZ_AFC_CLIENT);
2142 		case IEEE80211_6GHZ_CTRL_REG_VLP_AP:
2143 			return !(flags & IEEE80211_CHAN_NO_6GHZ_VLP_CLIENT);
2144 		}
2145 	}
2146 	return false;
2147 }
2148 
2149 /* Returned bss is reference counted and must be cleaned up appropriately. */
2150 static struct cfg80211_bss *
cfg80211_inform_single_bss_data(struct wiphy * wiphy,struct cfg80211_inform_single_bss_data * data,gfp_t gfp)2151 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
2152 				struct cfg80211_inform_single_bss_data *data,
2153 				gfp_t gfp)
2154 {
2155 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2156 	struct cfg80211_inform_bss *drv_data = data->drv_data;
2157 	struct cfg80211_bss_ies *ies;
2158 	struct ieee80211_channel *channel;
2159 	struct cfg80211_internal_bss tmp = {}, *res;
2160 	int bss_type;
2161 	bool signal_valid;
2162 	unsigned long ts;
2163 
2164 	if (WARN_ON(!wiphy))
2165 		return NULL;
2166 
2167 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2168 		    (drv_data->signal < 0 || drv_data->signal > 100)))
2169 		return NULL;
2170 
2171 	if (WARN_ON(data->bss_source != BSS_SOURCE_DIRECT && !data->source_bss))
2172 		return NULL;
2173 
2174 	channel = data->channel;
2175 	if (!channel)
2176 		channel = cfg80211_get_bss_channel(wiphy, data->ie, data->ielen,
2177 						   drv_data->chan);
2178 	if (!channel)
2179 		return NULL;
2180 
2181 	if (channel->band == NL80211_BAND_6GHZ &&
2182 	    !cfg80211_6ghz_power_type_valid(data->ie, data->ielen,
2183 					    channel->flags)) {
2184 		data->use_for = 0;
2185 		data->cannot_use_reasons =
2186 			NL80211_BSS_CANNOT_USE_6GHZ_PWR_MISMATCH;
2187 	}
2188 
2189 	memcpy(tmp.pub.bssid, data->bssid, ETH_ALEN);
2190 	tmp.pub.channel = channel;
2191 	if (data->bss_source != BSS_SOURCE_STA_PROFILE)
2192 		tmp.pub.signal = drv_data->signal;
2193 	else
2194 		tmp.pub.signal = 0;
2195 	tmp.pub.beacon_interval = data->beacon_interval;
2196 	tmp.pub.capability = data->capability;
2197 	tmp.ts_boottime = drv_data->boottime_ns;
2198 	tmp.parent_tsf = drv_data->parent_tsf;
2199 	ether_addr_copy(tmp.parent_bssid, drv_data->parent_bssid);
2200 	tmp.pub.chains = drv_data->chains;
2201 	memcpy(tmp.pub.chain_signal, drv_data->chain_signal,
2202 	       IEEE80211_MAX_CHAINS);
2203 	tmp.pub.use_for = data->use_for;
2204 	tmp.pub.cannot_use_reasons = data->cannot_use_reasons;
2205 
2206 	switch (data->bss_source) {
2207 	case BSS_SOURCE_MBSSID:
2208 		tmp.pub.transmitted_bss = data->source_bss;
2209 		fallthrough;
2210 	case BSS_SOURCE_STA_PROFILE:
2211 		ts = bss_from_pub(data->source_bss)->ts;
2212 		tmp.pub.bssid_index = data->bssid_index;
2213 		tmp.pub.max_bssid_indicator = data->max_bssid_indicator;
2214 		break;
2215 	case BSS_SOURCE_DIRECT:
2216 		ts = jiffies;
2217 
2218 		if (channel->band == NL80211_BAND_60GHZ) {
2219 			bss_type = data->capability &
2220 				   WLAN_CAPABILITY_DMG_TYPE_MASK;
2221 			if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2222 			    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2223 				regulatory_hint_found_beacon(wiphy, channel,
2224 							     gfp);
2225 		} else {
2226 			if (data->capability & WLAN_CAPABILITY_ESS)
2227 				regulatory_hint_found_beacon(wiphy, channel,
2228 							     gfp);
2229 		}
2230 		break;
2231 	}
2232 
2233 	/*
2234 	 * If we do not know here whether the IEs are from a Beacon or Probe
2235 	 * Response frame, we need to pick one of the options and only use it
2236 	 * with the driver that does not provide the full Beacon/Probe Response
2237 	 * frame. Use Beacon frame pointer to avoid indicating that this should
2238 	 * override the IEs pointer should we have received an earlier
2239 	 * indication of Probe Response data.
2240 	 */
2241 	ies = kzalloc(sizeof(*ies) + data->ielen, gfp);
2242 	if (!ies)
2243 		return NULL;
2244 	ies->len = data->ielen;
2245 	ies->tsf = data->tsf;
2246 	ies->from_beacon = false;
2247 	memcpy(ies->data, data->ie, data->ielen);
2248 
2249 	switch (data->ftype) {
2250 	case CFG80211_BSS_FTYPE_BEACON:
2251 	case CFG80211_BSS_FTYPE_S1G_BEACON:
2252 		ies->from_beacon = true;
2253 		fallthrough;
2254 	case CFG80211_BSS_FTYPE_UNKNOWN:
2255 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2256 		break;
2257 	case CFG80211_BSS_FTYPE_PRESP:
2258 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2259 		break;
2260 	}
2261 	rcu_assign_pointer(tmp.pub.ies, ies);
2262 
2263 	signal_valid = drv_data->chan == channel;
2264 	spin_lock_bh(&rdev->bss_lock);
2265 	res = __cfg80211_bss_update(rdev, &tmp, signal_valid, ts);
2266 	if (!res)
2267 		goto drop;
2268 
2269 	rdev_inform_bss(rdev, &res->pub, ies, drv_data->drv_data);
2270 
2271 	if (data->bss_source == BSS_SOURCE_MBSSID) {
2272 		/* this is a nontransmitting bss, we need to add it to
2273 		 * transmitting bss' list if it is not there
2274 		 */
2275 		if (cfg80211_add_nontrans_list(data->source_bss, &res->pub)) {
2276 			if (__cfg80211_unlink_bss(rdev, res)) {
2277 				rdev->bss_generation++;
2278 				res = NULL;
2279 			}
2280 		}
2281 
2282 		if (!res)
2283 			goto drop;
2284 	}
2285 	spin_unlock_bh(&rdev->bss_lock);
2286 
2287 	trace_cfg80211_return_bss(&res->pub);
2288 	/* __cfg80211_bss_update gives us a referenced result */
2289 	return &res->pub;
2290 
2291 drop:
2292 	spin_unlock_bh(&rdev->bss_lock);
2293 	return NULL;
2294 }
2295 
2296 static const struct element
cfg80211_get_profile_continuation(const u8 * ie,size_t ielen,const struct element * mbssid_elem,const struct element * sub_elem)2297 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
2298 				   const struct element *mbssid_elem,
2299 				   const struct element *sub_elem)
2300 {
2301 	const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
2302 	const struct element *next_mbssid;
2303 	const struct element *next_sub;
2304 
2305 	next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2306 					 mbssid_end,
2307 					 ielen - (mbssid_end - ie));
2308 
2309 	/*
2310 	 * If it is not the last subelement in current MBSSID IE or there isn't
2311 	 * a next MBSSID IE - profile is complete.
2312 	*/
2313 	if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2314 	    !next_mbssid)
2315 		return NULL;
2316 
2317 	/* For any length error, just return NULL */
2318 
2319 	if (next_mbssid->datalen < 4)
2320 		return NULL;
2321 
2322 	next_sub = (void *)&next_mbssid->data[1];
2323 
2324 	if (next_mbssid->data + next_mbssid->datalen <
2325 	    next_sub->data + next_sub->datalen)
2326 		return NULL;
2327 
2328 	if (next_sub->id != 0 || next_sub->datalen < 2)
2329 		return NULL;
2330 
2331 	/*
2332 	 * Check if the first element in the next sub element is a start
2333 	 * of a new profile
2334 	 */
2335 	return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2336 	       NULL : next_mbssid;
2337 }
2338 
cfg80211_merge_profile(const u8 * ie,size_t ielen,const struct element * mbssid_elem,const struct element * sub_elem,u8 * merged_ie,size_t max_copy_len)2339 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2340 			      const struct element *mbssid_elem,
2341 			      const struct element *sub_elem,
2342 			      u8 *merged_ie, size_t max_copy_len)
2343 {
2344 	size_t copied_len = sub_elem->datalen;
2345 	const struct element *next_mbssid;
2346 
2347 	if (sub_elem->datalen > max_copy_len)
2348 		return 0;
2349 
2350 	memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2351 
2352 	while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2353 								mbssid_elem,
2354 								sub_elem))) {
2355 		const struct element *next_sub = (void *)&next_mbssid->data[1];
2356 
2357 		if (copied_len + next_sub->datalen > max_copy_len)
2358 			break;
2359 		memcpy(merged_ie + copied_len, next_sub->data,
2360 		       next_sub->datalen);
2361 		copied_len += next_sub->datalen;
2362 	}
2363 
2364 	return copied_len;
2365 }
2366 EXPORT_SYMBOL(cfg80211_merge_profile);
2367 
2368 static void
cfg80211_parse_mbssid_data(struct wiphy * wiphy,struct cfg80211_inform_single_bss_data * tx_data,struct cfg80211_bss * source_bss,gfp_t gfp)2369 cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2370 			   struct cfg80211_inform_single_bss_data *tx_data,
2371 			   struct cfg80211_bss *source_bss,
2372 			   gfp_t gfp)
2373 {
2374 	struct cfg80211_inform_single_bss_data data = {
2375 		.drv_data = tx_data->drv_data,
2376 		.ftype = tx_data->ftype,
2377 		.tsf = tx_data->tsf,
2378 		.beacon_interval = tx_data->beacon_interval,
2379 		.source_bss = source_bss,
2380 		.bss_source = BSS_SOURCE_MBSSID,
2381 		.use_for = tx_data->use_for,
2382 		.cannot_use_reasons = tx_data->cannot_use_reasons,
2383 	};
2384 	const u8 *mbssid_index_ie;
2385 	const struct element *elem, *sub;
2386 	u8 *new_ie, *profile;
2387 	u64 seen_indices = 0;
2388 	struct cfg80211_bss *bss;
2389 
2390 	if (!source_bss)
2391 		return;
2392 	if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2393 				tx_data->ie, tx_data->ielen))
2394 		return;
2395 	if (!wiphy->support_mbssid)
2396 		return;
2397 	if (wiphy->support_only_he_mbssid &&
2398 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY,
2399 				    tx_data->ie, tx_data->ielen))
2400 		return;
2401 
2402 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2403 	if (!new_ie)
2404 		return;
2405 
2406 	profile = kmalloc(tx_data->ielen, gfp);
2407 	if (!profile)
2408 		goto out;
2409 
2410 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID,
2411 			    tx_data->ie, tx_data->ielen) {
2412 		if (elem->datalen < 4)
2413 			continue;
2414 		if (elem->data[0] < 1 || (int)elem->data[0] > 8)
2415 			continue;
2416 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2417 			u8 profile_len;
2418 
2419 			if (sub->id != 0 || sub->datalen < 4) {
2420 				/* not a valid BSS profile */
2421 				continue;
2422 			}
2423 
2424 			if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2425 			    sub->data[1] != 2) {
2426 				/* The first element within the Nontransmitted
2427 				 * BSSID Profile is not the Nontransmitted
2428 				 * BSSID Capability element.
2429 				 */
2430 				continue;
2431 			}
2432 
2433 			memset(profile, 0, tx_data->ielen);
2434 			profile_len = cfg80211_merge_profile(tx_data->ie,
2435 							     tx_data->ielen,
2436 							     elem,
2437 							     sub,
2438 							     profile,
2439 							     tx_data->ielen);
2440 
2441 			/* found a Nontransmitted BSSID Profile */
2442 			mbssid_index_ie = cfg80211_find_ie
2443 				(WLAN_EID_MULTI_BSSID_IDX,
2444 				 profile, profile_len);
2445 			if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2446 			    mbssid_index_ie[2] == 0 ||
2447 			    mbssid_index_ie[2] > 46 ||
2448 			    mbssid_index_ie[2] >= (1 << elem->data[0])) {
2449 				/* No valid Multiple BSSID-Index element */
2450 				continue;
2451 			}
2452 
2453 			if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2454 				/* We don't support legacy split of a profile */
2455 				net_dbg_ratelimited("Partial info for BSSID index %d\n",
2456 						    mbssid_index_ie[2]);
2457 
2458 			seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2459 
2460 			data.bssid_index = mbssid_index_ie[2];
2461 			data.max_bssid_indicator = elem->data[0];
2462 
2463 			cfg80211_gen_new_bssid(tx_data->bssid,
2464 					       data.max_bssid_indicator,
2465 					       data.bssid_index,
2466 					       data.bssid);
2467 
2468 			memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2469 			data.ie = new_ie;
2470 			data.ielen = cfg80211_gen_new_ie(tx_data->ie,
2471 							 tx_data->ielen,
2472 							 profile,
2473 							 profile_len,
2474 							 new_ie,
2475 							 IEEE80211_MAX_DATA_LEN);
2476 			if (!data.ielen)
2477 				continue;
2478 
2479 			data.capability = get_unaligned_le16(profile + 2);
2480 			bss = cfg80211_inform_single_bss_data(wiphy, &data, gfp);
2481 			if (!bss)
2482 				break;
2483 			cfg80211_put_bss(wiphy, bss);
2484 		}
2485 	}
2486 
2487 out:
2488 	kfree(new_ie);
2489 	kfree(profile);
2490 }
2491 
cfg80211_defragment_element(const struct element * elem,const u8 * ies,size_t ieslen,u8 * data,size_t data_len,u8 frag_id)2492 ssize_t cfg80211_defragment_element(const struct element *elem, const u8 *ies,
2493 				    size_t ieslen, u8 *data, size_t data_len,
2494 				    u8 frag_id)
2495 {
2496 	const struct element *next;
2497 	ssize_t copied;
2498 	u8 elem_datalen;
2499 
2500 	if (!elem)
2501 		return -EINVAL;
2502 
2503 	/* elem might be invalid after the memmove */
2504 	next = (void *)(elem->data + elem->datalen);
2505 	elem_datalen = elem->datalen;
2506 
2507 	if (elem->id == WLAN_EID_EXTENSION) {
2508 		copied = elem->datalen - 1;
2509 
2510 		if (data) {
2511 			if (copied > data_len)
2512 				return -ENOSPC;
2513 
2514 			memmove(data, elem->data + 1, copied);
2515 		}
2516 	} else {
2517 		copied = elem->datalen;
2518 
2519 		if (data) {
2520 			if (copied > data_len)
2521 				return -ENOSPC;
2522 
2523 			memmove(data, elem->data, copied);
2524 		}
2525 	}
2526 
2527 	/* Fragmented elements must have 255 bytes */
2528 	if (elem_datalen < 255)
2529 		return copied;
2530 
2531 	for (elem = next;
2532 	     elem->data < ies + ieslen &&
2533 		elem->data + elem->datalen <= ies + ieslen;
2534 	     elem = next) {
2535 		/* elem might be invalid after the memmove */
2536 		next = (void *)(elem->data + elem->datalen);
2537 
2538 		if (elem->id != frag_id)
2539 			break;
2540 
2541 		elem_datalen = elem->datalen;
2542 
2543 		if (data) {
2544 			if (copied + elem_datalen > data_len)
2545 				return -ENOSPC;
2546 
2547 			memmove(data + copied, elem->data, elem_datalen);
2548 		}
2549 
2550 		copied += elem_datalen;
2551 
2552 		/* Only the last fragment may be short */
2553 		if (elem_datalen != 255)
2554 			break;
2555 	}
2556 
2557 	return copied;
2558 }
2559 EXPORT_SYMBOL(cfg80211_defragment_element);
2560 
2561 struct cfg80211_mle {
2562 	struct ieee80211_multi_link_elem *mle;
2563 	struct ieee80211_mle_per_sta_profile
2564 		*sta_prof[IEEE80211_MLD_MAX_NUM_LINKS];
2565 	ssize_t sta_prof_len[IEEE80211_MLD_MAX_NUM_LINKS];
2566 
2567 	u8 data[];
2568 };
2569 
2570 static struct cfg80211_mle *
cfg80211_defrag_mle(const struct element * mle,const u8 * ie,size_t ielen,gfp_t gfp)2571 cfg80211_defrag_mle(const struct element *mle, const u8 *ie, size_t ielen,
2572 		    gfp_t gfp)
2573 {
2574 	const struct element *elem;
2575 	struct cfg80211_mle *res;
2576 	size_t buf_len;
2577 	ssize_t mle_len;
2578 	u8 common_size, idx;
2579 
2580 	if (!mle || !ieee80211_mle_size_ok(mle->data + 1, mle->datalen - 1))
2581 		return NULL;
2582 
2583 	/* Required length for first defragmentation */
2584 	buf_len = mle->datalen - 1;
2585 	for_each_element(elem, mle->data + mle->datalen,
2586 			 ielen - sizeof(*mle) + mle->datalen) {
2587 		if (elem->id != WLAN_EID_FRAGMENT)
2588 			break;
2589 
2590 		buf_len += elem->datalen;
2591 	}
2592 
2593 	res = kzalloc(struct_size(res, data, buf_len), gfp);
2594 	if (!res)
2595 		return NULL;
2596 
2597 	mle_len = cfg80211_defragment_element(mle, ie, ielen,
2598 					      res->data, buf_len,
2599 					      WLAN_EID_FRAGMENT);
2600 	if (mle_len < 0)
2601 		goto error;
2602 
2603 	res->mle = (void *)res->data;
2604 
2605 	/* Find the sub-element area in the buffer */
2606 	common_size = ieee80211_mle_common_size((u8 *)res->mle);
2607 	ie = res->data + common_size;
2608 	ielen = mle_len - common_size;
2609 
2610 	idx = 0;
2611 	for_each_element_id(elem, IEEE80211_MLE_SUBELEM_PER_STA_PROFILE,
2612 			    ie, ielen) {
2613 		res->sta_prof[idx] = (void *)elem->data;
2614 		res->sta_prof_len[idx] = elem->datalen;
2615 
2616 		idx++;
2617 		if (idx >= IEEE80211_MLD_MAX_NUM_LINKS)
2618 			break;
2619 	}
2620 	if (!for_each_element_completed(elem, ie, ielen))
2621 		goto error;
2622 
2623 	/* Defragment sta_info in-place */
2624 	for (idx = 0; idx < IEEE80211_MLD_MAX_NUM_LINKS && res->sta_prof[idx];
2625 	     idx++) {
2626 		if (res->sta_prof_len[idx] < 255)
2627 			continue;
2628 
2629 		elem = (void *)res->sta_prof[idx] - 2;
2630 
2631 		if (idx + 1 < ARRAY_SIZE(res->sta_prof) &&
2632 		    res->sta_prof[idx + 1])
2633 			buf_len = (u8 *)res->sta_prof[idx + 1] -
2634 				  (u8 *)res->sta_prof[idx];
2635 		else
2636 			buf_len = ielen + ie - (u8 *)elem;
2637 
2638 		res->sta_prof_len[idx] =
2639 			cfg80211_defragment_element(elem,
2640 						    (u8 *)elem, buf_len,
2641 						    (u8 *)res->sta_prof[idx],
2642 						    buf_len,
2643 						    IEEE80211_MLE_SUBELEM_FRAGMENT);
2644 		if (res->sta_prof_len[idx] < 0)
2645 			goto error;
2646 	}
2647 
2648 	return res;
2649 
2650 error:
2651 	kfree(res);
2652 	return NULL;
2653 }
2654 
2655 struct tbtt_info_iter_data {
2656 	const struct ieee80211_neighbor_ap_info *ap_info;
2657 	u8 param_ch_count;
2658 	u32 use_for;
2659 	u8 mld_id, link_id;
2660 	bool non_tx;
2661 };
2662 
2663 static enum cfg80211_rnr_iter_ret
cfg802121_mld_ap_rnr_iter(void * _data,u8 type,const struct ieee80211_neighbor_ap_info * info,const u8 * tbtt_info,u8 tbtt_info_len)2664 cfg802121_mld_ap_rnr_iter(void *_data, u8 type,
2665 			  const struct ieee80211_neighbor_ap_info *info,
2666 			  const u8 *tbtt_info, u8 tbtt_info_len)
2667 {
2668 	const struct ieee80211_rnr_mld_params *mld_params;
2669 	struct tbtt_info_iter_data *data = _data;
2670 	u8 link_id;
2671 	bool non_tx = false;
2672 
2673 	if (type == IEEE80211_TBTT_INFO_TYPE_TBTT &&
2674 	    tbtt_info_len >= offsetofend(struct ieee80211_tbtt_info_ge_11,
2675 					 mld_params)) {
2676 		const struct ieee80211_tbtt_info_ge_11 *tbtt_info_ge_11 =
2677 			(void *)tbtt_info;
2678 
2679 		non_tx = (tbtt_info_ge_11->bss_params &
2680 			  (IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID |
2681 			   IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID)) ==
2682 			 IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID;
2683 		mld_params = &tbtt_info_ge_11->mld_params;
2684 	} else if (type == IEEE80211_TBTT_INFO_TYPE_MLD &&
2685 		 tbtt_info_len >= sizeof(struct ieee80211_rnr_mld_params))
2686 		mld_params = (void *)tbtt_info;
2687 	else
2688 		return RNR_ITER_CONTINUE;
2689 
2690 	link_id = le16_get_bits(mld_params->params,
2691 				IEEE80211_RNR_MLD_PARAMS_LINK_ID);
2692 
2693 	if (data->mld_id != mld_params->mld_id)
2694 		return RNR_ITER_CONTINUE;
2695 
2696 	if (data->link_id != link_id)
2697 		return RNR_ITER_CONTINUE;
2698 
2699 	data->ap_info = info;
2700 	data->param_ch_count =
2701 		le16_get_bits(mld_params->params,
2702 			      IEEE80211_RNR_MLD_PARAMS_BSS_CHANGE_COUNT);
2703 	data->non_tx = non_tx;
2704 
2705 	if (type == IEEE80211_TBTT_INFO_TYPE_TBTT)
2706 		data->use_for = NL80211_BSS_USE_FOR_ALL;
2707 	else
2708 		data->use_for = NL80211_BSS_USE_FOR_MLD_LINK;
2709 	return RNR_ITER_BREAK;
2710 }
2711 
2712 static u8
cfg80211_rnr_info_for_mld_ap(const u8 * ie,size_t ielen,u8 mld_id,u8 link_id,const struct ieee80211_neighbor_ap_info ** ap_info,u8 * param_ch_count,bool * non_tx)2713 cfg80211_rnr_info_for_mld_ap(const u8 *ie, size_t ielen, u8 mld_id, u8 link_id,
2714 			     const struct ieee80211_neighbor_ap_info **ap_info,
2715 			     u8 *param_ch_count, bool *non_tx)
2716 {
2717 	struct tbtt_info_iter_data data = {
2718 		.mld_id = mld_id,
2719 		.link_id = link_id,
2720 	};
2721 
2722 	cfg80211_iter_rnr(ie, ielen, cfg802121_mld_ap_rnr_iter, &data);
2723 
2724 	*ap_info = data.ap_info;
2725 	*param_ch_count = data.param_ch_count;
2726 	*non_tx = data.non_tx;
2727 
2728 	return data.use_for;
2729 }
2730 
2731 static struct element *
cfg80211_gen_reporter_rnr(struct cfg80211_bss * source_bss,bool is_mbssid,bool same_mld,u8 link_id,u8 bss_change_count,gfp_t gfp)2732 cfg80211_gen_reporter_rnr(struct cfg80211_bss *source_bss, bool is_mbssid,
2733 			  bool same_mld, u8 link_id, u8 bss_change_count,
2734 			  gfp_t gfp)
2735 {
2736 	const struct cfg80211_bss_ies *ies;
2737 	struct ieee80211_neighbor_ap_info ap_info;
2738 	struct ieee80211_tbtt_info_ge_11 tbtt_info;
2739 	u32 short_ssid;
2740 	const struct element *elem;
2741 	struct element *res;
2742 
2743 	/*
2744 	 * We only generate the RNR to permit ML lookups. For that we do not
2745 	 * need an entry for the corresponding transmitting BSS, lets just skip
2746 	 * it even though it would be easy to add.
2747 	 */
2748 	if (!same_mld)
2749 		return NULL;
2750 
2751 	/* We could use tx_data->ies if we change cfg80211_calc_short_ssid */
2752 	rcu_read_lock();
2753 	ies = rcu_dereference(source_bss->ies);
2754 
2755 	ap_info.tbtt_info_len = offsetofend(typeof(tbtt_info), mld_params);
2756 	ap_info.tbtt_info_hdr =
2757 			u8_encode_bits(IEEE80211_TBTT_INFO_TYPE_TBTT,
2758 				       IEEE80211_AP_INFO_TBTT_HDR_TYPE) |
2759 			u8_encode_bits(0, IEEE80211_AP_INFO_TBTT_HDR_COUNT);
2760 
2761 	ap_info.channel = ieee80211_frequency_to_channel(source_bss->channel->center_freq);
2762 
2763 	/* operating class */
2764 	elem = cfg80211_find_elem(WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
2765 				  ies->data, ies->len);
2766 	if (elem && elem->datalen >= 1) {
2767 		ap_info.op_class = elem->data[0];
2768 	} else {
2769 		struct cfg80211_chan_def chandef;
2770 
2771 		/* The AP is not providing us with anything to work with. So
2772 		 * make up a somewhat reasonable operating class, but don't
2773 		 * bother with it too much as no one will ever use the
2774 		 * information.
2775 		 */
2776 		cfg80211_chandef_create(&chandef, source_bss->channel,
2777 					NL80211_CHAN_NO_HT);
2778 
2779 		if (!ieee80211_chandef_to_operating_class(&chandef,
2780 							  &ap_info.op_class))
2781 			goto out_unlock;
2782 	}
2783 
2784 	/* Just set TBTT offset and PSD 20 to invalid/unknown */
2785 	tbtt_info.tbtt_offset = 255;
2786 	tbtt_info.psd_20 = IEEE80211_RNR_TBTT_PARAMS_PSD_RESERVED;
2787 
2788 	memcpy(tbtt_info.bssid, source_bss->bssid, ETH_ALEN);
2789 	if (cfg80211_calc_short_ssid(ies, &elem, &short_ssid))
2790 		goto out_unlock;
2791 
2792 	rcu_read_unlock();
2793 
2794 	tbtt_info.short_ssid = cpu_to_le32(short_ssid);
2795 
2796 	tbtt_info.bss_params = IEEE80211_RNR_TBTT_PARAMS_SAME_SSID;
2797 
2798 	if (is_mbssid) {
2799 		tbtt_info.bss_params |= IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID;
2800 		tbtt_info.bss_params |= IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID;
2801 	}
2802 
2803 	tbtt_info.mld_params.mld_id = 0;
2804 	tbtt_info.mld_params.params =
2805 		le16_encode_bits(link_id, IEEE80211_RNR_MLD_PARAMS_LINK_ID) |
2806 		le16_encode_bits(bss_change_count,
2807 				 IEEE80211_RNR_MLD_PARAMS_BSS_CHANGE_COUNT);
2808 
2809 	res = kzalloc(struct_size(res, data,
2810 				  sizeof(ap_info) + ap_info.tbtt_info_len),
2811 		      gfp);
2812 	if (!res)
2813 		return NULL;
2814 
2815 	/* Copy the data */
2816 	res->id = WLAN_EID_REDUCED_NEIGHBOR_REPORT;
2817 	res->datalen = sizeof(ap_info) + ap_info.tbtt_info_len;
2818 	memcpy(res->data, &ap_info, sizeof(ap_info));
2819 	memcpy(res->data + sizeof(ap_info), &tbtt_info, ap_info.tbtt_info_len);
2820 
2821 	return res;
2822 
2823 out_unlock:
2824 	rcu_read_unlock();
2825 	return NULL;
2826 }
2827 
2828 static void
cfg80211_parse_ml_elem_sta_data(struct wiphy * wiphy,struct cfg80211_inform_single_bss_data * tx_data,struct cfg80211_bss * source_bss,const struct element * elem,gfp_t gfp)2829 cfg80211_parse_ml_elem_sta_data(struct wiphy *wiphy,
2830 				struct cfg80211_inform_single_bss_data *tx_data,
2831 				struct cfg80211_bss *source_bss,
2832 				const struct element *elem,
2833 				gfp_t gfp)
2834 {
2835 	struct cfg80211_inform_single_bss_data data = {
2836 		.drv_data = tx_data->drv_data,
2837 		.ftype = tx_data->ftype,
2838 		.source_bss = source_bss,
2839 		.bss_source = BSS_SOURCE_STA_PROFILE,
2840 	};
2841 	struct element *reporter_rnr = NULL;
2842 	struct ieee80211_multi_link_elem *ml_elem;
2843 	struct cfg80211_mle *mle;
2844 	u16 control;
2845 	u8 ml_common_len;
2846 	u8 *new_ie = NULL;
2847 	struct cfg80211_bss *bss;
2848 	u8 mld_id, reporter_link_id, bss_change_count;
2849 	u16 seen_links = 0;
2850 	u8 i;
2851 
2852 	if (!ieee80211_mle_type_ok(elem->data + 1,
2853 				   IEEE80211_ML_CONTROL_TYPE_BASIC,
2854 				   elem->datalen - 1))
2855 		return;
2856 
2857 	ml_elem = (void *)(elem->data + 1);
2858 	control = le16_to_cpu(ml_elem->control);
2859 	ml_common_len = ml_elem->variable[0];
2860 
2861 	/* Must be present when transmitted by an AP (in a probe response) */
2862 	if (!(control & IEEE80211_MLC_BASIC_PRES_BSS_PARAM_CH_CNT) ||
2863 	    !(control & IEEE80211_MLC_BASIC_PRES_LINK_ID) ||
2864 	    !(control & IEEE80211_MLC_BASIC_PRES_MLD_CAPA_OP))
2865 		return;
2866 
2867 	reporter_link_id = ieee80211_mle_get_link_id(elem->data + 1);
2868 	bss_change_count = ieee80211_mle_get_bss_param_ch_cnt(elem->data + 1);
2869 
2870 	/*
2871 	 * The MLD ID of the reporting AP is always zero. It is set if the AP
2872 	 * is part of an MBSSID set and will be non-zero for ML Elements
2873 	 * relating to a nontransmitted BSS (matching the Multi-BSSID Index,
2874 	 * Draft P802.11be_D3.2, 35.3.4.2)
2875 	 */
2876 	mld_id = ieee80211_mle_get_mld_id(elem->data + 1);
2877 
2878 	/* Fully defrag the ML element for sta information/profile iteration */
2879 	mle = cfg80211_defrag_mle(elem, tx_data->ie, tx_data->ielen, gfp);
2880 	if (!mle)
2881 		return;
2882 
2883 	/* No point in doing anything if there is no per-STA profile */
2884 	if (!mle->sta_prof[0])
2885 		goto out;
2886 
2887 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2888 	if (!new_ie)
2889 		goto out;
2890 
2891 	reporter_rnr = cfg80211_gen_reporter_rnr(source_bss,
2892 						 u16_get_bits(control,
2893 							      IEEE80211_MLC_BASIC_PRES_MLD_ID),
2894 						 mld_id == 0, reporter_link_id,
2895 						 bss_change_count,
2896 						 gfp);
2897 
2898 	for (i = 0; i < ARRAY_SIZE(mle->sta_prof) && mle->sta_prof[i]; i++) {
2899 		const struct ieee80211_neighbor_ap_info *ap_info;
2900 		enum nl80211_band band;
2901 		u32 freq;
2902 		const u8 *profile;
2903 		ssize_t profile_len;
2904 		u8 param_ch_count;
2905 		u8 link_id, use_for;
2906 		bool non_tx;
2907 
2908 		if (!ieee80211_mle_basic_sta_prof_size_ok((u8 *)mle->sta_prof[i],
2909 							  mle->sta_prof_len[i]))
2910 			continue;
2911 
2912 		control = le16_to_cpu(mle->sta_prof[i]->control);
2913 
2914 		if (!(control & IEEE80211_MLE_STA_CONTROL_COMPLETE_PROFILE))
2915 			continue;
2916 
2917 		link_id = u16_get_bits(control,
2918 				       IEEE80211_MLE_STA_CONTROL_LINK_ID);
2919 		if (seen_links & BIT(link_id))
2920 			break;
2921 		seen_links |= BIT(link_id);
2922 
2923 		if (!(control & IEEE80211_MLE_STA_CONTROL_BEACON_INT_PRESENT) ||
2924 		    !(control & IEEE80211_MLE_STA_CONTROL_TSF_OFFS_PRESENT) ||
2925 		    !(control & IEEE80211_MLE_STA_CONTROL_STA_MAC_ADDR_PRESENT))
2926 			continue;
2927 
2928 		memcpy(data.bssid, mle->sta_prof[i]->variable, ETH_ALEN);
2929 		data.beacon_interval =
2930 			get_unaligned_le16(mle->sta_prof[i]->variable + 6);
2931 		data.tsf = tx_data->tsf +
2932 			   get_unaligned_le64(mle->sta_prof[i]->variable + 8);
2933 
2934 		/* sta_info_len counts itself */
2935 		profile = mle->sta_prof[i]->variable +
2936 			  mle->sta_prof[i]->sta_info_len - 1;
2937 		profile_len = (u8 *)mle->sta_prof[i] + mle->sta_prof_len[i] -
2938 			      profile;
2939 
2940 		if (profile_len < 2)
2941 			continue;
2942 
2943 		data.capability = get_unaligned_le16(profile);
2944 		profile += 2;
2945 		profile_len -= 2;
2946 
2947 		/* Find in RNR to look up channel information */
2948 		use_for = cfg80211_rnr_info_for_mld_ap(tx_data->ie,
2949 						       tx_data->ielen,
2950 						       mld_id, link_id,
2951 						       &ap_info,
2952 						       &param_ch_count,
2953 						       &non_tx);
2954 		if (!use_for)
2955 			continue;
2956 
2957 		/*
2958 		 * As of 802.11be_D5.0, the specification does not give us any
2959 		 * way of discovering both the MaxBSSID and the Multiple-BSSID
2960 		 * Index. It does seem like the Multiple-BSSID Index element
2961 		 * may be provided, but section 9.4.2.45 explicitly forbids
2962 		 * including a Multiple-BSSID Element (in this case without any
2963 		 * subelements).
2964 		 * Without both pieces of information we cannot calculate the
2965 		 * reference BSSID, so simply ignore the BSS.
2966 		 */
2967 		if (non_tx)
2968 			continue;
2969 
2970 		/* We could sanity check the BSSID is included */
2971 
2972 		if (!ieee80211_operating_class_to_band(ap_info->op_class,
2973 						       &band))
2974 			continue;
2975 
2976 		freq = ieee80211_channel_to_freq_khz(ap_info->channel, band);
2977 		data.channel = ieee80211_get_channel_khz(wiphy, freq);
2978 
2979 		if (use_for == NL80211_BSS_USE_FOR_MLD_LINK &&
2980 		    !(wiphy->flags & WIPHY_FLAG_SUPPORTS_NSTR_NONPRIMARY)) {
2981 			use_for = 0;
2982 			data.cannot_use_reasons =
2983 				NL80211_BSS_CANNOT_USE_NSTR_NONPRIMARY;
2984 		}
2985 		data.use_for = use_for;
2986 
2987 		/* Generate new elements */
2988 		memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2989 		data.ie = new_ie;
2990 		data.ielen = cfg80211_gen_new_ie(tx_data->ie, tx_data->ielen,
2991 						 profile, profile_len,
2992 						 new_ie,
2993 						 IEEE80211_MAX_DATA_LEN);
2994 		if (!data.ielen)
2995 			continue;
2996 
2997 		/* The generated elements do not contain:
2998 		 *  - Basic ML element
2999 		 *  - A TBTT entry in the RNR for the transmitting AP
3000 		 *
3001 		 * This information is needed both internally and in userspace
3002 		 * as such, we should append it here.
3003 		 */
3004 		if (data.ielen + 3 + sizeof(*ml_elem) + ml_common_len >
3005 		    IEEE80211_MAX_DATA_LEN)
3006 			continue;
3007 
3008 		/* Copy the Basic Multi-Link element including the common
3009 		 * information, and then fix up the link ID and BSS param
3010 		 * change count.
3011 		 * Note that the ML element length has been verified and we
3012 		 * also checked that it contains the link ID.
3013 		 */
3014 		new_ie[data.ielen++] = WLAN_EID_EXTENSION;
3015 		new_ie[data.ielen++] = 1 + sizeof(*ml_elem) + ml_common_len;
3016 		new_ie[data.ielen++] = WLAN_EID_EXT_EHT_MULTI_LINK;
3017 		memcpy(new_ie + data.ielen, ml_elem,
3018 		       sizeof(*ml_elem) + ml_common_len);
3019 
3020 		new_ie[data.ielen + sizeof(*ml_elem) + 1 + ETH_ALEN] = link_id;
3021 		new_ie[data.ielen + sizeof(*ml_elem) + 1 + ETH_ALEN + 1] =
3022 			param_ch_count;
3023 
3024 		data.ielen += sizeof(*ml_elem) + ml_common_len;
3025 
3026 		if (reporter_rnr && (use_for & NL80211_BSS_USE_FOR_NORMAL)) {
3027 			if (data.ielen + sizeof(struct element) +
3028 			    reporter_rnr->datalen > IEEE80211_MAX_DATA_LEN)
3029 				continue;
3030 
3031 			memcpy(new_ie + data.ielen, reporter_rnr,
3032 			       sizeof(struct element) + reporter_rnr->datalen);
3033 			data.ielen += sizeof(struct element) +
3034 				      reporter_rnr->datalen;
3035 		}
3036 
3037 		bss = cfg80211_inform_single_bss_data(wiphy, &data, gfp);
3038 		if (!bss)
3039 			break;
3040 		cfg80211_put_bss(wiphy, bss);
3041 	}
3042 
3043 out:
3044 	kfree(reporter_rnr);
3045 	kfree(new_ie);
3046 	kfree(mle);
3047 }
3048 
cfg80211_parse_ml_sta_data(struct wiphy * wiphy,struct cfg80211_inform_single_bss_data * tx_data,struct cfg80211_bss * source_bss,gfp_t gfp)3049 static void cfg80211_parse_ml_sta_data(struct wiphy *wiphy,
3050 				       struct cfg80211_inform_single_bss_data *tx_data,
3051 				       struct cfg80211_bss *source_bss,
3052 				       gfp_t gfp)
3053 {
3054 	const struct element *elem;
3055 
3056 	if (!source_bss)
3057 		return;
3058 
3059 	if (tx_data->ftype != CFG80211_BSS_FTYPE_PRESP)
3060 		return;
3061 
3062 	for_each_element_extid(elem, WLAN_EID_EXT_EHT_MULTI_LINK,
3063 			       tx_data->ie, tx_data->ielen)
3064 		cfg80211_parse_ml_elem_sta_data(wiphy, tx_data, source_bss,
3065 						elem, gfp);
3066 }
3067 
3068 struct cfg80211_bss *
cfg80211_inform_bss_data(struct wiphy * wiphy,struct cfg80211_inform_bss * data,enum cfg80211_bss_frame_type ftype,const u8 * bssid,u64 tsf,u16 capability,u16 beacon_interval,const u8 * ie,size_t ielen,gfp_t gfp)3069 cfg80211_inform_bss_data(struct wiphy *wiphy,
3070 			 struct cfg80211_inform_bss *data,
3071 			 enum cfg80211_bss_frame_type ftype,
3072 			 const u8 *bssid, u64 tsf, u16 capability,
3073 			 u16 beacon_interval, const u8 *ie, size_t ielen,
3074 			 gfp_t gfp)
3075 {
3076 	struct cfg80211_inform_single_bss_data inform_data = {
3077 		.drv_data = data,
3078 		.ftype = ftype,
3079 		.tsf = tsf,
3080 		.capability = capability,
3081 		.beacon_interval = beacon_interval,
3082 		.ie = ie,
3083 		.ielen = ielen,
3084 		.use_for = data->restrict_use ?
3085 				data->use_for :
3086 				NL80211_BSS_USE_FOR_ALL,
3087 		.cannot_use_reasons = data->cannot_use_reasons,
3088 	};
3089 	struct cfg80211_bss *res;
3090 
3091 	memcpy(inform_data.bssid, bssid, ETH_ALEN);
3092 
3093 	res = cfg80211_inform_single_bss_data(wiphy, &inform_data, gfp);
3094 	if (!res)
3095 		return NULL;
3096 
3097 	/* don't do any further MBSSID/ML handling for S1G */
3098 	if (ftype == CFG80211_BSS_FTYPE_S1G_BEACON)
3099 		return res;
3100 
3101 	cfg80211_parse_mbssid_data(wiphy, &inform_data, res, gfp);
3102 
3103 	cfg80211_parse_ml_sta_data(wiphy, &inform_data, res, gfp);
3104 
3105 	return res;
3106 }
3107 EXPORT_SYMBOL(cfg80211_inform_bss_data);
3108 
3109 struct cfg80211_bss *
cfg80211_inform_bss_frame_data(struct wiphy * wiphy,struct cfg80211_inform_bss * data,struct ieee80211_mgmt * mgmt,size_t len,gfp_t gfp)3110 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
3111 			       struct cfg80211_inform_bss *data,
3112 			       struct ieee80211_mgmt *mgmt, size_t len,
3113 			       gfp_t gfp)
3114 {
3115 	size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
3116 				      u.probe_resp.variable);
3117 	struct ieee80211_ext *ext = NULL;
3118 	enum cfg80211_bss_frame_type ftype;
3119 	u16 beacon_interval;
3120 	const u8 *bssid;
3121 	u16 capability;
3122 	const u8 *ie;
3123 	size_t ielen;
3124 	u64 tsf;
3125 
3126 	if (WARN_ON(!mgmt))
3127 		return NULL;
3128 
3129 	if (WARN_ON(!wiphy))
3130 		return NULL;
3131 
3132 	BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
3133 		     offsetof(struct ieee80211_mgmt, u.beacon.variable));
3134 
3135 	trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
3136 
3137 	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
3138 		ext = (void *) mgmt;
3139 		min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
3140 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
3141 			min_hdr_len = offsetof(struct ieee80211_ext,
3142 					       u.s1g_short_beacon.variable);
3143 	}
3144 
3145 	if (WARN_ON(len < min_hdr_len))
3146 		return NULL;
3147 
3148 	ielen = len - min_hdr_len;
3149 	ie = mgmt->u.probe_resp.variable;
3150 	if (ext) {
3151 		const struct ieee80211_s1g_bcn_compat_ie *compat;
3152 		const struct element *elem;
3153 
3154 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
3155 			ie = ext->u.s1g_short_beacon.variable;
3156 		else
3157 			ie = ext->u.s1g_beacon.variable;
3158 
3159 		elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT, ie, ielen);
3160 		if (!elem)
3161 			return NULL;
3162 		if (elem->datalen < sizeof(*compat))
3163 			return NULL;
3164 		compat = (void *)elem->data;
3165 		bssid = ext->u.s1g_beacon.sa;
3166 		capability = le16_to_cpu(compat->compat_info);
3167 		beacon_interval = le16_to_cpu(compat->beacon_int);
3168 	} else {
3169 		bssid = mgmt->bssid;
3170 		beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
3171 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
3172 	}
3173 
3174 	tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
3175 
3176 	if (ieee80211_is_probe_resp(mgmt->frame_control))
3177 		ftype = CFG80211_BSS_FTYPE_PRESP;
3178 	else if (ext)
3179 		ftype = CFG80211_BSS_FTYPE_S1G_BEACON;
3180 	else
3181 		ftype = CFG80211_BSS_FTYPE_BEACON;
3182 
3183 	return cfg80211_inform_bss_data(wiphy, data, ftype,
3184 					bssid, tsf, capability,
3185 					beacon_interval, ie, ielen,
3186 					gfp);
3187 }
3188 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
3189 
cfg80211_ref_bss(struct wiphy * wiphy,struct cfg80211_bss * pub)3190 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
3191 {
3192 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3193 
3194 	if (!pub)
3195 		return;
3196 
3197 	spin_lock_bh(&rdev->bss_lock);
3198 	bss_ref_get(rdev, bss_from_pub(pub));
3199 	spin_unlock_bh(&rdev->bss_lock);
3200 }
3201 EXPORT_SYMBOL(cfg80211_ref_bss);
3202 
cfg80211_put_bss(struct wiphy * wiphy,struct cfg80211_bss * pub)3203 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
3204 {
3205 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3206 
3207 	if (!pub)
3208 		return;
3209 
3210 	spin_lock_bh(&rdev->bss_lock);
3211 	bss_ref_put(rdev, bss_from_pub(pub));
3212 	spin_unlock_bh(&rdev->bss_lock);
3213 }
3214 EXPORT_SYMBOL(cfg80211_put_bss);
3215 
cfg80211_unlink_bss(struct wiphy * wiphy,struct cfg80211_bss * pub)3216 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
3217 {
3218 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3219 	struct cfg80211_internal_bss *bss, *tmp1;
3220 	struct cfg80211_bss *nontrans_bss, *tmp;
3221 
3222 	if (WARN_ON(!pub))
3223 		return;
3224 
3225 	bss = bss_from_pub(pub);
3226 
3227 	spin_lock_bh(&rdev->bss_lock);
3228 	if (list_empty(&bss->list))
3229 		goto out;
3230 
3231 	list_for_each_entry_safe(nontrans_bss, tmp,
3232 				 &pub->nontrans_list,
3233 				 nontrans_list) {
3234 		tmp1 = bss_from_pub(nontrans_bss);
3235 		if (__cfg80211_unlink_bss(rdev, tmp1))
3236 			rdev->bss_generation++;
3237 	}
3238 
3239 	if (__cfg80211_unlink_bss(rdev, bss))
3240 		rdev->bss_generation++;
3241 out:
3242 	spin_unlock_bh(&rdev->bss_lock);
3243 }
3244 EXPORT_SYMBOL(cfg80211_unlink_bss);
3245 
cfg80211_bss_iter(struct wiphy * wiphy,struct cfg80211_chan_def * chandef,void (* iter)(struct wiphy * wiphy,struct cfg80211_bss * bss,void * data),void * iter_data)3246 void cfg80211_bss_iter(struct wiphy *wiphy,
3247 		       struct cfg80211_chan_def *chandef,
3248 		       void (*iter)(struct wiphy *wiphy,
3249 				    struct cfg80211_bss *bss,
3250 				    void *data),
3251 		       void *iter_data)
3252 {
3253 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3254 	struct cfg80211_internal_bss *bss;
3255 
3256 	spin_lock_bh(&rdev->bss_lock);
3257 
3258 	list_for_each_entry(bss, &rdev->bss_list, list) {
3259 		if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel,
3260 						     false))
3261 			iter(wiphy, &bss->pub, iter_data);
3262 	}
3263 
3264 	spin_unlock_bh(&rdev->bss_lock);
3265 }
3266 EXPORT_SYMBOL(cfg80211_bss_iter);
3267 
cfg80211_update_assoc_bss_entry(struct wireless_dev * wdev,unsigned int link_id,struct ieee80211_channel * chan)3268 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
3269 				     unsigned int link_id,
3270 				     struct ieee80211_channel *chan)
3271 {
3272 	struct wiphy *wiphy = wdev->wiphy;
3273 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3274 	struct cfg80211_internal_bss *cbss = wdev->links[link_id].client.current_bss;
3275 	struct cfg80211_internal_bss *new = NULL;
3276 	struct cfg80211_internal_bss *bss;
3277 	struct cfg80211_bss *nontrans_bss;
3278 	struct cfg80211_bss *tmp;
3279 
3280 	spin_lock_bh(&rdev->bss_lock);
3281 
3282 	/*
3283 	 * Some APs use CSA also for bandwidth changes, i.e., without actually
3284 	 * changing the control channel, so no need to update in such a case.
3285 	 */
3286 	if (cbss->pub.channel == chan)
3287 		goto done;
3288 
3289 	/* use transmitting bss */
3290 	if (cbss->pub.transmitted_bss)
3291 		cbss = bss_from_pub(cbss->pub.transmitted_bss);
3292 
3293 	cbss->pub.channel = chan;
3294 
3295 	list_for_each_entry(bss, &rdev->bss_list, list) {
3296 		if (!cfg80211_bss_type_match(bss->pub.capability,
3297 					     bss->pub.channel->band,
3298 					     wdev->conn_bss_type))
3299 			continue;
3300 
3301 		if (bss == cbss)
3302 			continue;
3303 
3304 		if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
3305 			new = bss;
3306 			break;
3307 		}
3308 	}
3309 
3310 	if (new) {
3311 		/* to save time, update IEs for transmitting bss only */
3312 		cfg80211_update_known_bss(rdev, cbss, new, false);
3313 		new->pub.proberesp_ies = NULL;
3314 		new->pub.beacon_ies = NULL;
3315 
3316 		list_for_each_entry_safe(nontrans_bss, tmp,
3317 					 &new->pub.nontrans_list,
3318 					 nontrans_list) {
3319 			bss = bss_from_pub(nontrans_bss);
3320 			if (__cfg80211_unlink_bss(rdev, bss))
3321 				rdev->bss_generation++;
3322 		}
3323 
3324 		WARN_ON(atomic_read(&new->hold));
3325 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
3326 			rdev->bss_generation++;
3327 	}
3328 
3329 	rb_erase(&cbss->rbn, &rdev->bss_tree);
3330 	rb_insert_bss(rdev, cbss);
3331 	rdev->bss_generation++;
3332 
3333 	list_for_each_entry_safe(nontrans_bss, tmp,
3334 				 &cbss->pub.nontrans_list,
3335 				 nontrans_list) {
3336 		bss = bss_from_pub(nontrans_bss);
3337 		bss->pub.channel = chan;
3338 		rb_erase(&bss->rbn, &rdev->bss_tree);
3339 		rb_insert_bss(rdev, bss);
3340 		rdev->bss_generation++;
3341 	}
3342 
3343 done:
3344 	spin_unlock_bh(&rdev->bss_lock);
3345 }
3346 
3347 #ifdef CONFIG_CFG80211_WEXT
3348 static struct cfg80211_registered_device *
cfg80211_get_dev_from_ifindex(struct net * net,int ifindex)3349 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
3350 {
3351 	struct cfg80211_registered_device *rdev;
3352 	struct net_device *dev;
3353 
3354 	ASSERT_RTNL();
3355 
3356 	dev = dev_get_by_index(net, ifindex);
3357 	if (!dev)
3358 		return ERR_PTR(-ENODEV);
3359 	if (dev->ieee80211_ptr)
3360 		rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
3361 	else
3362 		rdev = ERR_PTR(-ENODEV);
3363 	dev_put(dev);
3364 	return rdev;
3365 }
3366 
cfg80211_wext_siwscan(struct net_device * dev,struct iw_request_info * info,union iwreq_data * wrqu,char * extra)3367 int cfg80211_wext_siwscan(struct net_device *dev,
3368 			  struct iw_request_info *info,
3369 			  union iwreq_data *wrqu, char *extra)
3370 {
3371 	struct cfg80211_registered_device *rdev;
3372 	struct wiphy *wiphy;
3373 	struct iw_scan_req *wreq = NULL;
3374 	struct cfg80211_scan_request *creq;
3375 	int i, err, n_channels = 0;
3376 	enum nl80211_band band;
3377 
3378 	if (!netif_running(dev))
3379 		return -ENETDOWN;
3380 
3381 	if (wrqu->data.length == sizeof(struct iw_scan_req))
3382 		wreq = (struct iw_scan_req *)extra;
3383 
3384 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3385 
3386 	if (IS_ERR(rdev))
3387 		return PTR_ERR(rdev);
3388 
3389 	if (rdev->scan_req || rdev->scan_msg)
3390 		return -EBUSY;
3391 
3392 	wiphy = &rdev->wiphy;
3393 
3394 	/* Determine number of channels, needed to allocate creq */
3395 	if (wreq && wreq->num_channels) {
3396 		/* Passed from userspace so should be checked */
3397 		if (unlikely(wreq->num_channels > IW_MAX_FREQUENCIES))
3398 			return -EINVAL;
3399 		n_channels = wreq->num_channels;
3400 	} else {
3401 		n_channels = ieee80211_get_num_supported_channels(wiphy);
3402 	}
3403 
3404 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
3405 		       n_channels * sizeof(void *),
3406 		       GFP_ATOMIC);
3407 	if (!creq)
3408 		return -ENOMEM;
3409 
3410 	creq->wiphy = wiphy;
3411 	creq->wdev = dev->ieee80211_ptr;
3412 	/* SSIDs come after channels */
3413 	creq->ssids = (void *)&creq->channels[n_channels];
3414 	creq->n_channels = n_channels;
3415 	creq->n_ssids = 1;
3416 	creq->scan_start = jiffies;
3417 
3418 	/* translate "Scan on frequencies" request */
3419 	i = 0;
3420 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
3421 		int j;
3422 
3423 		if (!wiphy->bands[band])
3424 			continue;
3425 
3426 		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
3427 			/* ignore disabled channels */
3428 			if (wiphy->bands[band]->channels[j].flags &
3429 						IEEE80211_CHAN_DISABLED)
3430 				continue;
3431 
3432 			/* If we have a wireless request structure and the
3433 			 * wireless request specifies frequencies, then search
3434 			 * for the matching hardware channel.
3435 			 */
3436 			if (wreq && wreq->num_channels) {
3437 				int k;
3438 				int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
3439 				for (k = 0; k < wreq->num_channels; k++) {
3440 					struct iw_freq *freq =
3441 						&wreq->channel_list[k];
3442 					int wext_freq =
3443 						cfg80211_wext_freq(freq);
3444 
3445 					if (wext_freq == wiphy_freq)
3446 						goto wext_freq_found;
3447 				}
3448 				goto wext_freq_not_found;
3449 			}
3450 
3451 		wext_freq_found:
3452 			creq->channels[i] = &wiphy->bands[band]->channels[j];
3453 			i++;
3454 		wext_freq_not_found: ;
3455 		}
3456 	}
3457 	/* No channels found? */
3458 	if (!i) {
3459 		err = -EINVAL;
3460 		goto out;
3461 	}
3462 
3463 	/* Set real number of channels specified in creq->channels[] */
3464 	creq->n_channels = i;
3465 
3466 	/* translate "Scan for SSID" request */
3467 	if (wreq) {
3468 		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
3469 			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
3470 				err = -EINVAL;
3471 				goto out;
3472 			}
3473 			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
3474 			creq->ssids[0].ssid_len = wreq->essid_len;
3475 		}
3476 		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) {
3477 			creq->ssids = NULL;
3478 			creq->n_ssids = 0;
3479 		}
3480 	}
3481 
3482 	for (i = 0; i < NUM_NL80211_BANDS; i++)
3483 		if (wiphy->bands[i])
3484 			creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
3485 
3486 	eth_broadcast_addr(creq->bssid);
3487 
3488 	wiphy_lock(&rdev->wiphy);
3489 
3490 	rdev->scan_req = creq;
3491 	err = rdev_scan(rdev, creq);
3492 	if (err) {
3493 		rdev->scan_req = NULL;
3494 		/* creq will be freed below */
3495 	} else {
3496 		nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
3497 		/* creq now owned by driver */
3498 		creq = NULL;
3499 		dev_hold(dev);
3500 	}
3501 	wiphy_unlock(&rdev->wiphy);
3502  out:
3503 	kfree(creq);
3504 	return err;
3505 }
3506 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
3507 
ieee80211_scan_add_ies(struct iw_request_info * info,const struct cfg80211_bss_ies * ies,char * current_ev,char * end_buf)3508 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
3509 				    const struct cfg80211_bss_ies *ies,
3510 				    char *current_ev, char *end_buf)
3511 {
3512 	const u8 *pos, *end, *next;
3513 	struct iw_event iwe;
3514 
3515 	if (!ies)
3516 		return current_ev;
3517 
3518 	/*
3519 	 * If needed, fragment the IEs buffer (at IE boundaries) into short
3520 	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
3521 	 */
3522 	pos = ies->data;
3523 	end = pos + ies->len;
3524 
3525 	while (end - pos > IW_GENERIC_IE_MAX) {
3526 		next = pos + 2 + pos[1];
3527 		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
3528 			next = next + 2 + next[1];
3529 
3530 		memset(&iwe, 0, sizeof(iwe));
3531 		iwe.cmd = IWEVGENIE;
3532 		iwe.u.data.length = next - pos;
3533 		current_ev = iwe_stream_add_point_check(info, current_ev,
3534 							end_buf, &iwe,
3535 							(void *)pos);
3536 		if (IS_ERR(current_ev))
3537 			return current_ev;
3538 		pos = next;
3539 	}
3540 
3541 	if (end > pos) {
3542 		memset(&iwe, 0, sizeof(iwe));
3543 		iwe.cmd = IWEVGENIE;
3544 		iwe.u.data.length = end - pos;
3545 		current_ev = iwe_stream_add_point_check(info, current_ev,
3546 							end_buf, &iwe,
3547 							(void *)pos);
3548 		if (IS_ERR(current_ev))
3549 			return current_ev;
3550 	}
3551 
3552 	return current_ev;
3553 }
3554 
3555 static char *
ieee80211_bss(struct wiphy * wiphy,struct iw_request_info * info,struct cfg80211_internal_bss * bss,char * current_ev,char * end_buf)3556 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
3557 	      struct cfg80211_internal_bss *bss, char *current_ev,
3558 	      char *end_buf)
3559 {
3560 	const struct cfg80211_bss_ies *ies;
3561 	struct iw_event iwe;
3562 	const u8 *ie;
3563 	u8 buf[50];
3564 	u8 *cfg, *p, *tmp;
3565 	int rem, i, sig;
3566 	bool ismesh = false;
3567 
3568 	memset(&iwe, 0, sizeof(iwe));
3569 	iwe.cmd = SIOCGIWAP;
3570 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
3571 	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
3572 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3573 						IW_EV_ADDR_LEN);
3574 	if (IS_ERR(current_ev))
3575 		return current_ev;
3576 
3577 	memset(&iwe, 0, sizeof(iwe));
3578 	iwe.cmd = SIOCGIWFREQ;
3579 	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
3580 	iwe.u.freq.e = 0;
3581 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3582 						IW_EV_FREQ_LEN);
3583 	if (IS_ERR(current_ev))
3584 		return current_ev;
3585 
3586 	memset(&iwe, 0, sizeof(iwe));
3587 	iwe.cmd = SIOCGIWFREQ;
3588 	iwe.u.freq.m = bss->pub.channel->center_freq;
3589 	iwe.u.freq.e = 6;
3590 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3591 						IW_EV_FREQ_LEN);
3592 	if (IS_ERR(current_ev))
3593 		return current_ev;
3594 
3595 	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
3596 		memset(&iwe, 0, sizeof(iwe));
3597 		iwe.cmd = IWEVQUAL;
3598 		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
3599 				     IW_QUAL_NOISE_INVALID |
3600 				     IW_QUAL_QUAL_UPDATED;
3601 		switch (wiphy->signal_type) {
3602 		case CFG80211_SIGNAL_TYPE_MBM:
3603 			sig = bss->pub.signal / 100;
3604 			iwe.u.qual.level = sig;
3605 			iwe.u.qual.updated |= IW_QUAL_DBM;
3606 			if (sig < -110)		/* rather bad */
3607 				sig = -110;
3608 			else if (sig > -40)	/* perfect */
3609 				sig = -40;
3610 			/* will give a range of 0 .. 70 */
3611 			iwe.u.qual.qual = sig + 110;
3612 			break;
3613 		case CFG80211_SIGNAL_TYPE_UNSPEC:
3614 			iwe.u.qual.level = bss->pub.signal;
3615 			/* will give range 0 .. 100 */
3616 			iwe.u.qual.qual = bss->pub.signal;
3617 			break;
3618 		default:
3619 			/* not reached */
3620 			break;
3621 		}
3622 		current_ev = iwe_stream_add_event_check(info, current_ev,
3623 							end_buf, &iwe,
3624 							IW_EV_QUAL_LEN);
3625 		if (IS_ERR(current_ev))
3626 			return current_ev;
3627 	}
3628 
3629 	memset(&iwe, 0, sizeof(iwe));
3630 	iwe.cmd = SIOCGIWENCODE;
3631 	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
3632 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
3633 	else
3634 		iwe.u.data.flags = IW_ENCODE_DISABLED;
3635 	iwe.u.data.length = 0;
3636 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3637 						&iwe, "");
3638 	if (IS_ERR(current_ev))
3639 		return current_ev;
3640 
3641 	rcu_read_lock();
3642 	ies = rcu_dereference(bss->pub.ies);
3643 	rem = ies->len;
3644 	ie = ies->data;
3645 
3646 	while (rem >= 2) {
3647 		/* invalid data */
3648 		if (ie[1] > rem - 2)
3649 			break;
3650 
3651 		switch (ie[0]) {
3652 		case WLAN_EID_SSID:
3653 			memset(&iwe, 0, sizeof(iwe));
3654 			iwe.cmd = SIOCGIWESSID;
3655 			iwe.u.data.length = ie[1];
3656 			iwe.u.data.flags = 1;
3657 			current_ev = iwe_stream_add_point_check(info,
3658 								current_ev,
3659 								end_buf, &iwe,
3660 								(u8 *)ie + 2);
3661 			if (IS_ERR(current_ev))
3662 				goto unlock;
3663 			break;
3664 		case WLAN_EID_MESH_ID:
3665 			memset(&iwe, 0, sizeof(iwe));
3666 			iwe.cmd = SIOCGIWESSID;
3667 			iwe.u.data.length = ie[1];
3668 			iwe.u.data.flags = 1;
3669 			current_ev = iwe_stream_add_point_check(info,
3670 								current_ev,
3671 								end_buf, &iwe,
3672 								(u8 *)ie + 2);
3673 			if (IS_ERR(current_ev))
3674 				goto unlock;
3675 			break;
3676 		case WLAN_EID_MESH_CONFIG:
3677 			ismesh = true;
3678 			if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
3679 				break;
3680 			cfg = (u8 *)ie + 2;
3681 			memset(&iwe, 0, sizeof(iwe));
3682 			iwe.cmd = IWEVCUSTOM;
3683 			sprintf(buf, "Mesh Network Path Selection Protocol ID: "
3684 				"0x%02X", cfg[0]);
3685 			iwe.u.data.length = strlen(buf);
3686 			current_ev = iwe_stream_add_point_check(info,
3687 								current_ev,
3688 								end_buf,
3689 								&iwe, buf);
3690 			if (IS_ERR(current_ev))
3691 				goto unlock;
3692 			sprintf(buf, "Path Selection Metric ID: 0x%02X",
3693 				cfg[1]);
3694 			iwe.u.data.length = strlen(buf);
3695 			current_ev = iwe_stream_add_point_check(info,
3696 								current_ev,
3697 								end_buf,
3698 								&iwe, buf);
3699 			if (IS_ERR(current_ev))
3700 				goto unlock;
3701 			sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3702 				cfg[2]);
3703 			iwe.u.data.length = strlen(buf);
3704 			current_ev = iwe_stream_add_point_check(info,
3705 								current_ev,
3706 								end_buf,
3707 								&iwe, buf);
3708 			if (IS_ERR(current_ev))
3709 				goto unlock;
3710 			sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3711 			iwe.u.data.length = strlen(buf);
3712 			current_ev = iwe_stream_add_point_check(info,
3713 								current_ev,
3714 								end_buf,
3715 								&iwe, buf);
3716 			if (IS_ERR(current_ev))
3717 				goto unlock;
3718 			sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3719 			iwe.u.data.length = strlen(buf);
3720 			current_ev = iwe_stream_add_point_check(info,
3721 								current_ev,
3722 								end_buf,
3723 								&iwe, buf);
3724 			if (IS_ERR(current_ev))
3725 				goto unlock;
3726 			sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3727 			iwe.u.data.length = strlen(buf);
3728 			current_ev = iwe_stream_add_point_check(info,
3729 								current_ev,
3730 								end_buf,
3731 								&iwe, buf);
3732 			if (IS_ERR(current_ev))
3733 				goto unlock;
3734 			sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3735 			iwe.u.data.length = strlen(buf);
3736 			current_ev = iwe_stream_add_point_check(info,
3737 								current_ev,
3738 								end_buf,
3739 								&iwe, buf);
3740 			if (IS_ERR(current_ev))
3741 				goto unlock;
3742 			break;
3743 		case WLAN_EID_SUPP_RATES:
3744 		case WLAN_EID_EXT_SUPP_RATES:
3745 			/* display all supported rates in readable format */
3746 			p = current_ev + iwe_stream_lcp_len(info);
3747 
3748 			memset(&iwe, 0, sizeof(iwe));
3749 			iwe.cmd = SIOCGIWRATE;
3750 			/* Those two flags are ignored... */
3751 			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3752 
3753 			for (i = 0; i < ie[1]; i++) {
3754 				iwe.u.bitrate.value =
3755 					((ie[i + 2] & 0x7f) * 500000);
3756 				tmp = p;
3757 				p = iwe_stream_add_value(info, current_ev, p,
3758 							 end_buf, &iwe,
3759 							 IW_EV_PARAM_LEN);
3760 				if (p == tmp) {
3761 					current_ev = ERR_PTR(-E2BIG);
3762 					goto unlock;
3763 				}
3764 			}
3765 			current_ev = p;
3766 			break;
3767 		}
3768 		rem -= ie[1] + 2;
3769 		ie += ie[1] + 2;
3770 	}
3771 
3772 	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3773 	    ismesh) {
3774 		memset(&iwe, 0, sizeof(iwe));
3775 		iwe.cmd = SIOCGIWMODE;
3776 		if (ismesh)
3777 			iwe.u.mode = IW_MODE_MESH;
3778 		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3779 			iwe.u.mode = IW_MODE_MASTER;
3780 		else
3781 			iwe.u.mode = IW_MODE_ADHOC;
3782 		current_ev = iwe_stream_add_event_check(info, current_ev,
3783 							end_buf, &iwe,
3784 							IW_EV_UINT_LEN);
3785 		if (IS_ERR(current_ev))
3786 			goto unlock;
3787 	}
3788 
3789 	memset(&iwe, 0, sizeof(iwe));
3790 	iwe.cmd = IWEVCUSTOM;
3791 	sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3792 	iwe.u.data.length = strlen(buf);
3793 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3794 						&iwe, buf);
3795 	if (IS_ERR(current_ev))
3796 		goto unlock;
3797 	memset(&iwe, 0, sizeof(iwe));
3798 	iwe.cmd = IWEVCUSTOM;
3799 	sprintf(buf, " Last beacon: %ums ago",
3800 		elapsed_jiffies_msecs(bss->ts));
3801 	iwe.u.data.length = strlen(buf);
3802 	current_ev = iwe_stream_add_point_check(info, current_ev,
3803 						end_buf, &iwe, buf);
3804 	if (IS_ERR(current_ev))
3805 		goto unlock;
3806 
3807 	current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3808 
3809  unlock:
3810 	rcu_read_unlock();
3811 	return current_ev;
3812 }
3813 
3814 
ieee80211_scan_results(struct cfg80211_registered_device * rdev,struct iw_request_info * info,char * buf,size_t len)3815 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3816 				  struct iw_request_info *info,
3817 				  char *buf, size_t len)
3818 {
3819 	char *current_ev = buf;
3820 	char *end_buf = buf + len;
3821 	struct cfg80211_internal_bss *bss;
3822 	int err = 0;
3823 
3824 	spin_lock_bh(&rdev->bss_lock);
3825 	cfg80211_bss_expire(rdev);
3826 
3827 	list_for_each_entry(bss, &rdev->bss_list, list) {
3828 		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3829 			err = -E2BIG;
3830 			break;
3831 		}
3832 		current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3833 					   current_ev, end_buf);
3834 		if (IS_ERR(current_ev)) {
3835 			err = PTR_ERR(current_ev);
3836 			break;
3837 		}
3838 	}
3839 	spin_unlock_bh(&rdev->bss_lock);
3840 
3841 	if (err)
3842 		return err;
3843 	return current_ev - buf;
3844 }
3845 
3846 
cfg80211_wext_giwscan(struct net_device * dev,struct iw_request_info * info,union iwreq_data * wrqu,char * extra)3847 int cfg80211_wext_giwscan(struct net_device *dev,
3848 			  struct iw_request_info *info,
3849 			  union iwreq_data *wrqu, char *extra)
3850 {
3851 	struct iw_point *data = &wrqu->data;
3852 	struct cfg80211_registered_device *rdev;
3853 	int res;
3854 
3855 	if (!netif_running(dev))
3856 		return -ENETDOWN;
3857 
3858 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3859 
3860 	if (IS_ERR(rdev))
3861 		return PTR_ERR(rdev);
3862 
3863 	if (rdev->scan_req || rdev->scan_msg)
3864 		return -EAGAIN;
3865 
3866 	res = ieee80211_scan_results(rdev, info, extra, data->length);
3867 	data->length = 0;
3868 	if (res >= 0) {
3869 		data->length = res;
3870 		res = 0;
3871 	}
3872 
3873 	return res;
3874 }
3875 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3876 #endif
3877