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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) 2018-2021 Intel Corporation
9 */
10#include <linux/kernel.h>
11#include <linux/slab.h>
12#include <linux/module.h>
13#include <linux/netdevice.h>
14#include <linux/wireless.h>
15#include <linux/nl80211.h>
16#include <linux/etherdevice.h>
17#include <linux/crc32.h>
18#include <linux/bitfield.h>
19#include <net/arp.h>
20#include <net/cfg80211.h>
21#include <net/cfg80211-wext.h>
22#include <net/iw_handler.h>
23#include "core.h"
24#include "nl80211.h"
25#include "wext-compat.h"
26#include "rdev-ops.h"
27
28/**
29 * DOC: BSS tree/list structure
30 *
31 * At the top level, the BSS list is kept in both a list in each
32 * registered device (@bss_list) as well as an RB-tree for faster
33 * lookup. In the RB-tree, entries can be looked up using their
34 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
35 * for other BSSes.
36 *
37 * Due to the possibility of hidden SSIDs, there's a second level
38 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
39 * The hidden_list connects all BSSes belonging to a single AP
40 * that has a hidden SSID, and connects beacon and probe response
41 * entries. For a probe response entry for a hidden SSID, the
42 * hidden_beacon_bss pointer points to the BSS struct holding the
43 * beacon's information.
44 *
45 * Reference counting is done for all these references except for
46 * the hidden_list, so that a beacon BSS struct that is otherwise
47 * not referenced has one reference for being on the bss_list and
48 * one for each probe response entry that points to it using the
49 * hidden_beacon_bss pointer. When a BSS struct that has such a
50 * pointer is get/put, the refcount update is also propagated to
51 * the referenced struct, this ensure that it cannot get removed
52 * while somebody is using the probe response version.
53 *
54 * Note that the hidden_beacon_bss pointer never changes, due to
55 * the reference counting. Therefore, no locking is needed for
56 * it.
57 *
58 * Also note that the hidden_beacon_bss pointer is only relevant
59 * if the driver uses something other than the IEs, e.g. private
60 * data stored in the BSS struct, since the beacon IEs are
61 * also linked into the probe response struct.
62 */
63
64/*
65 * Limit the number of BSS entries stored in mac80211. Each one is
66 * a bit over 4k at most, so this limits to roughly 4-5M of memory.
67 * If somebody wants to really attack this though, they'd likely
68 * use small beacons, and only one type of frame, limiting each of
69 * the entries to a much smaller size (in order to generate more
70 * entries in total, so overhead is bigger.)
71 */
72static int bss_entries_limit = 1000;
73module_param(bss_entries_limit, int, 0644);
74MODULE_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 */
100struct cfg80211_colocated_ap {
101 struct list_head list;
102 u8 bssid[ETH_ALEN];
103 u8 ssid[IEEE80211_MAX_SSID_LEN];
104 size_t ssid_len;
105 u32 short_ssid;
106 u32 center_freq;
107 u8 unsolicited_probe:1,
108 oct_recommended:1,
109 same_ssid:1,
110 multi_bss:1,
111 transmitted_bssid:1,
112 colocated_ess:1,
113 short_ssid_valid:1;
114};
115
116static void bss_free(struct cfg80211_internal_bss *bss)
117{
118 struct cfg80211_bss_ies *ies;
119
120 if (WARN_ON(atomic_read(&bss->hold)))
121 return;
122
123 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
124 if (ies && !bss->pub.hidden_beacon_bss)
125 kfree_rcu(ies, rcu_head);
126 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
127 if (ies)
128 kfree_rcu(ies, rcu_head);
129
130 /*
131 * This happens when the module is removed, it doesn't
132 * really matter any more save for completeness
133 */
134 if (!list_empty(&bss->hidden_list))
135 list_del(&bss->hidden_list);
136
137 kfree(bss);
138}
139
140static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
141 struct cfg80211_internal_bss *bss)
142{
143 lockdep_assert_held(&rdev->bss_lock);
144
145 bss->refcount++;
146 if (bss->pub.hidden_beacon_bss) {
147 bss = container_of(bss->pub.hidden_beacon_bss,
148 struct cfg80211_internal_bss,
149 pub);
150 bss->refcount++;
151 }
152 if (bss->pub.transmitted_bss) {
153 bss = container_of(bss->pub.transmitted_bss,
154 struct cfg80211_internal_bss,
155 pub);
156 bss->refcount++;
157 }
158}
159
160static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
161 struct cfg80211_internal_bss *bss)
162{
163 lockdep_assert_held(&rdev->bss_lock);
164
165 if (bss->pub.hidden_beacon_bss) {
166 struct cfg80211_internal_bss *hbss;
167 hbss = container_of(bss->pub.hidden_beacon_bss,
168 struct cfg80211_internal_bss,
169 pub);
170 hbss->refcount--;
171 if (hbss->refcount == 0)
172 bss_free(hbss);
173 }
174
175 if (bss->pub.transmitted_bss) {
176 struct cfg80211_internal_bss *tbss;
177
178 tbss = container_of(bss->pub.transmitted_bss,
179 struct cfg80211_internal_bss,
180 pub);
181 tbss->refcount--;
182 if (tbss->refcount == 0)
183 bss_free(tbss);
184 }
185
186 bss->refcount--;
187 if (bss->refcount == 0)
188 bss_free(bss);
189}
190
191static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
192 struct cfg80211_internal_bss *bss)
193{
194 lockdep_assert_held(&rdev->bss_lock);
195
196 if (!list_empty(&bss->hidden_list)) {
197 /*
198 * don't remove the beacon entry if it has
199 * probe responses associated with it
200 */
201 if (!bss->pub.hidden_beacon_bss)
202 return false;
203 /*
204 * if it's a probe response entry break its
205 * link to the other entries in the group
206 */
207 list_del_init(&bss->hidden_list);
208 }
209
210 list_del_init(&bss->list);
211 list_del_init(&bss->pub.nontrans_list);
212 rb_erase(&bss->rbn, &rdev->bss_tree);
213 rdev->bss_entries--;
214 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
215 "rdev bss entries[%d]/list[empty:%d] corruption\n",
216 rdev->bss_entries, list_empty(&rdev->bss_list));
217 bss_ref_put(rdev, bss);
218 return true;
219}
220
221bool cfg80211_is_element_inherited(const struct element *elem,
222 const struct element *non_inherit_elem)
223{
224 u8 id_len, ext_id_len, i, loop_len, id;
225 const u8 *list;
226
227 if (elem->id == WLAN_EID_MULTIPLE_BSSID)
228 return false;
229
230 if (!non_inherit_elem || non_inherit_elem->datalen < 2)
231 return true;
232
233 /*
234 * non inheritance element format is:
235 * ext ID (56) | IDs list len | list | extension IDs list len | list
236 * Both lists are optional. Both lengths are mandatory.
237 * This means valid length is:
238 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
239 */
240 id_len = non_inherit_elem->data[1];
241 if (non_inherit_elem->datalen < 3 + id_len)
242 return true;
243
244 ext_id_len = non_inherit_elem->data[2 + id_len];
245 if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
246 return true;
247
248 if (elem->id == WLAN_EID_EXTENSION) {
249 if (!ext_id_len)
250 return true;
251 loop_len = ext_id_len;
252 list = &non_inherit_elem->data[3 + id_len];
253 id = elem->data[0];
254 } else {
255 if (!id_len)
256 return true;
257 loop_len = id_len;
258 list = &non_inherit_elem->data[2];
259 id = elem->id;
260 }
261
262 for (i = 0; i < loop_len; i++) {
263 if (list[i] == id)
264 return false;
265 }
266
267 return true;
268}
269EXPORT_SYMBOL(cfg80211_is_element_inherited);
270
271static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
272 const u8 *subelement, size_t subie_len,
273 u8 *new_ie, gfp_t gfp)
274{
275 u8 *pos, *tmp;
276 const u8 *tmp_old, *tmp_new;
277 const struct element *non_inherit_elem;
278 u8 *sub_copy;
279
280 /* copy subelement as we need to change its content to
281 * mark an ie after it is processed.
282 */
283 sub_copy = kmemdup(subelement, subie_len, gfp);
284 if (!sub_copy)
285 return 0;
286
287 pos = &new_ie[0];
288
289 /* set new ssid */
290 tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
291 if (tmp_new) {
292 memcpy(pos, tmp_new, tmp_new[1] + 2);
293 pos += (tmp_new[1] + 2);
294 }
295
296 /* get non inheritance list if exists */
297 non_inherit_elem =
298 cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
299 sub_copy, subie_len);
300
301 /* go through IEs in ie (skip SSID) and subelement,
302 * merge them into new_ie
303 */
304 tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
305 tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
306
307 while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {
308 if (tmp_old[0] == 0) {
309 tmp_old++;
310 continue;
311 }
312
313 if (tmp_old[0] == WLAN_EID_EXTENSION)
314 tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
315 subie_len);
316 else
317 tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
318 subie_len);
319
320 if (!tmp) {
321 const struct element *old_elem = (void *)tmp_old;
322
323 /* ie in old ie but not in subelement */
324 if (cfg80211_is_element_inherited(old_elem,
325 non_inherit_elem)) {
326 memcpy(pos, tmp_old, tmp_old[1] + 2);
327 pos += tmp_old[1] + 2;
328 }
329 } else {
330 /* ie in transmitting ie also in subelement,
331 * copy from subelement and flag the ie in subelement
332 * as copied (by setting eid field to WLAN_EID_SSID,
333 * which is skipped anyway).
334 * For vendor ie, compare OUI + type + subType to
335 * determine if they are the same ie.
336 */
337 if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
338 if (!memcmp(tmp_old + 2, tmp + 2, 5)) {
339 /* same vendor ie, copy from
340 * subelement
341 */
342 memcpy(pos, tmp, tmp[1] + 2);
343 pos += tmp[1] + 2;
344 tmp[0] = WLAN_EID_SSID;
345 } else {
346 memcpy(pos, tmp_old, tmp_old[1] + 2);
347 pos += tmp_old[1] + 2;
348 }
349 } else {
350 /* copy ie from subelement into new ie */
351 memcpy(pos, tmp, tmp[1] + 2);
352 pos += tmp[1] + 2;
353 tmp[0] = WLAN_EID_SSID;
354 }
355 }
356
357 if (tmp_old + tmp_old[1] + 2 - ie == ielen)
358 break;
359
360 tmp_old += tmp_old[1] + 2;
361 }
362
363 /* go through subelement again to check if there is any ie not
364 * copied to new ie, skip ssid, capability, bssid-index ie
365 */
366 tmp_new = sub_copy;
367 while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
368 if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
369 tmp_new[0] == WLAN_EID_SSID)) {
370 memcpy(pos, tmp_new, tmp_new[1] + 2);
371 pos += tmp_new[1] + 2;
372 }
373 if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
374 break;
375 tmp_new += tmp_new[1] + 2;
376 }
377
378 kfree(sub_copy);
379 return pos - new_ie;
380}
381
382static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
383 const u8 *ssid, size_t ssid_len)
384{
385 const struct cfg80211_bss_ies *ies;
386 const u8 *ssidie;
387
388 if (bssid && !ether_addr_equal(a->bssid, bssid))
389 return false;
390
391 if (!ssid)
392 return true;
393
394 ies = rcu_access_pointer(a->ies);
395 if (!ies)
396 return false;
397 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
398 if (!ssidie)
399 return false;
400 if (ssidie[1] != ssid_len)
401 return false;
402 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
403}
404
405static int
406cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
407 struct cfg80211_bss *nontrans_bss)
408{
409 const u8 *ssid;
410 size_t ssid_len;
411 struct cfg80211_bss *bss = NULL;
412
413 rcu_read_lock();
414 ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
415 if (!ssid) {
416 rcu_read_unlock();
417 return -EINVAL;
418 }
419 ssid_len = ssid[1];
420 ssid = ssid + 2;
421 rcu_read_unlock();
422
423 /* check if nontrans_bss is in the list */
424 list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
425 if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
426 return 0;
427 }
428
429 /* add to the list */
430 list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
431 return 0;
432}
433
434static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
435 unsigned long expire_time)
436{
437 struct cfg80211_internal_bss *bss, *tmp;
438 bool expired = false;
439
440 lockdep_assert_held(&rdev->bss_lock);
441
442 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
443 if (atomic_read(&bss->hold))
444 continue;
445 if (!time_after(expire_time, bss->ts))
446 continue;
447
448 if (__cfg80211_unlink_bss(rdev, bss))
449 expired = true;
450 }
451
452 if (expired)
453 rdev->bss_generation++;
454}
455
456static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
457{
458 struct cfg80211_internal_bss *bss, *oldest = NULL;
459 bool ret;
460
461 lockdep_assert_held(&rdev->bss_lock);
462
463 list_for_each_entry(bss, &rdev->bss_list, list) {
464 if (atomic_read(&bss->hold))
465 continue;
466
467 if (!list_empty(&bss->hidden_list) &&
468 !bss->pub.hidden_beacon_bss)
469 continue;
470
471 if (oldest && time_before(oldest->ts, bss->ts))
472 continue;
473 oldest = bss;
474 }
475
476 if (WARN_ON(!oldest))
477 return false;
478
479 /*
480 * The callers make sure to increase rdev->bss_generation if anything
481 * gets removed (and a new entry added), so there's no need to also do
482 * it here.
483 */
484
485 ret = __cfg80211_unlink_bss(rdev, oldest);
486 WARN_ON(!ret);
487 return ret;
488}
489
490static u8 cfg80211_parse_bss_param(u8 data,
491 struct cfg80211_colocated_ap *coloc_ap)
492{
493 coloc_ap->oct_recommended =
494 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
495 coloc_ap->same_ssid =
496 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
497 coloc_ap->multi_bss =
498 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
499 coloc_ap->transmitted_bssid =
500 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
501 coloc_ap->unsolicited_probe =
502 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
503 coloc_ap->colocated_ess =
504 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
505
506 return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
507}
508
509static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
510 const struct element **elem, u32 *s_ssid)
511{
512
513 *elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
514 if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
515 return -EINVAL;
516
517 *s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
518 return 0;
519}
520
521static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
522{
523 struct cfg80211_colocated_ap *ap, *tmp_ap;
524
525 list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
526 list_del(&ap->list);
527 kfree(ap);
528 }
529}
530
531static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
532 const u8 *pos, u8 length,
533 const struct element *ssid_elem,
534 int s_ssid_tmp)
535{
536 /* skip the TBTT offset */
537 pos++;
538
539 memcpy(entry->bssid, pos, ETH_ALEN);
540 pos += ETH_ALEN;
541
542 if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) {
543 memcpy(&entry->short_ssid, pos,
544 sizeof(entry->short_ssid));
545 entry->short_ssid_valid = true;
546 pos += 4;
547 }
548
549 /* skip non colocated APs */
550 if (!cfg80211_parse_bss_param(*pos, entry))
551 return -EINVAL;
552 pos++;
553
554 if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) {
555 /*
556 * no information about the short ssid. Consider the entry valid
557 * for now. It would later be dropped in case there are explicit
558 * SSIDs that need to be matched
559 */
560 if (!entry->same_ssid)
561 return 0;
562 }
563
564 if (entry->same_ssid) {
565 entry->short_ssid = s_ssid_tmp;
566 entry->short_ssid_valid = true;
567
568 /*
569 * This is safe because we validate datalen in
570 * cfg80211_parse_colocated_ap(), before calling this
571 * function.
572 */
573 memcpy(&entry->ssid, &ssid_elem->data,
574 ssid_elem->datalen);
575 entry->ssid_len = ssid_elem->datalen;
576 }
577 return 0;
578}
579
580static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
581 struct list_head *list)
582{
583 struct ieee80211_neighbor_ap_info *ap_info;
584 const struct element *elem, *ssid_elem;
585 const u8 *pos, *end;
586 u32 s_ssid_tmp;
587 int n_coloc = 0, ret;
588 LIST_HEAD(ap_list);
589
590 elem = cfg80211_find_elem(WLAN_EID_REDUCED_NEIGHBOR_REPORT, ies->data,
591 ies->len);
592 if (!elem)
593 return 0;
594
595 pos = elem->data;
596 end = pos + elem->datalen;
597
598 ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp);
599 if (ret)
600 return ret;
601
602 /* RNR IE may contain more than one NEIGHBOR_AP_INFO */
603 while (pos + sizeof(*ap_info) <= end) {
604 enum nl80211_band band;
605 int freq;
606 u8 length, i, count;
607
608 ap_info = (void *)pos;
609 count = u8_get_bits(ap_info->tbtt_info_hdr,
610 IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
611 length = ap_info->tbtt_info_len;
612
613 pos += sizeof(*ap_info);
614
615 if (!ieee80211_operating_class_to_band(ap_info->op_class,
616 &band))
617 break;
618
619 freq = ieee80211_channel_to_frequency(ap_info->channel, band);
620
621 if (end - pos < count * length)
622 break;
623
624 /*
625 * TBTT info must include bss param + BSSID +
626 * (short SSID or same_ssid bit to be set).
627 * ignore other options, and move to the
628 * next AP info
629 */
630 if (band != NL80211_BAND_6GHZ ||
631 (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&
632 length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {
633 pos += count * length;
634 continue;
635 }
636
637 for (i = 0; i < count; i++) {
638 struct cfg80211_colocated_ap *entry;
639
640 entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
641 GFP_ATOMIC);
642
643 if (!entry)
644 break;
645
646 entry->center_freq = freq;
647
648 if (!cfg80211_parse_ap_info(entry, pos, length,
649 ssid_elem, s_ssid_tmp)) {
650 n_coloc++;
651 list_add_tail(&entry->list, &ap_list);
652 } else {
653 kfree(entry);
654 }
655
656 pos += length;
657 }
658 }
659
660 if (pos != end) {
661 cfg80211_free_coloc_ap_list(&ap_list);
662 return 0;
663 }
664
665 list_splice_tail(&ap_list, list);
666 return n_coloc;
667}
668
669static void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
670 struct ieee80211_channel *chan,
671 bool add_to_6ghz)
672{
673 int i;
674 u32 n_channels = request->n_channels;
675 struct cfg80211_scan_6ghz_params *params =
676 &request->scan_6ghz_params[request->n_6ghz_params];
677
678 for (i = 0; i < n_channels; i++) {
679 if (request->channels[i] == chan) {
680 if (add_to_6ghz)
681 params->channel_idx = i;
682 return;
683 }
684 }
685
686 request->channels[n_channels] = chan;
687 if (add_to_6ghz)
688 request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
689 n_channels;
690
691 request->n_channels++;
692}
693
694static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
695 struct cfg80211_scan_request *request)
696{
697 int i;
698 u32 s_ssid;
699
700 for (i = 0; i < request->n_ssids; i++) {
701 /* wildcard ssid in the scan request */
702 if (!request->ssids[i].ssid_len)
703 return true;
704
705 if (ap->ssid_len &&
706 ap->ssid_len == request->ssids[i].ssid_len) {
707 if (!memcmp(request->ssids[i].ssid, ap->ssid,
708 ap->ssid_len))
709 return true;
710 } else if (ap->short_ssid_valid) {
711 s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
712 request->ssids[i].ssid_len);
713
714 if (ap->short_ssid == s_ssid)
715 return true;
716 }
717 }
718
719 return false;
720}
721
722static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
723{
724 u8 i;
725 struct cfg80211_colocated_ap *ap;
726 int n_channels, count = 0, err;
727 struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
728 LIST_HEAD(coloc_ap_list);
729 bool need_scan_psc = true;
730 const struct ieee80211_sband_iftype_data *iftd;
731
732 rdev_req->scan_6ghz = true;
733
734 if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
735 return -EOPNOTSUPP;
736
737 iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
738 rdev_req->wdev->iftype);
739 if (!iftd || !iftd->he_cap.has_he)
740 return -EOPNOTSUPP;
741
742 n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
743
744 if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
745 struct cfg80211_internal_bss *intbss;
746
747 spin_lock_bh(&rdev->bss_lock);
748 list_for_each_entry(intbss, &rdev->bss_list, list) {
749 struct cfg80211_bss *res = &intbss->pub;
750 const struct cfg80211_bss_ies *ies;
751
752 ies = rcu_access_pointer(res->ies);
753 count += cfg80211_parse_colocated_ap(ies,
754 &coloc_ap_list);
755 }
756 spin_unlock_bh(&rdev->bss_lock);
757 }
758
759 request = kzalloc(struct_size(request, channels, n_channels) +
760 sizeof(*request->scan_6ghz_params) * count +
761 sizeof(*request->ssids) * rdev_req->n_ssids,
762 GFP_KERNEL);
763 if (!request) {
764 cfg80211_free_coloc_ap_list(&coloc_ap_list);
765 return -ENOMEM;
766 }
767
768 *request = *rdev_req;
769 request->n_channels = 0;
770 request->scan_6ghz_params =
771 (void *)&request->channels[n_channels];
772
773 /*
774 * PSC channels should not be scanned in case of direct scan with 1 SSID
775 * and at least one of the reported co-located APs with same SSID
776 * indicating that all APs in the same ESS are co-located
777 */
778 if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
779 list_for_each_entry(ap, &coloc_ap_list, list) {
780 if (ap->colocated_ess &&
781 cfg80211_find_ssid_match(ap, request)) {
782 need_scan_psc = false;
783 break;
784 }
785 }
786 }
787
788 /*
789 * add to the scan request the channels that need to be scanned
790 * regardless of the collocated APs (PSC channels or all channels
791 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
792 */
793 for (i = 0; i < rdev_req->n_channels; i++) {
794 if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
795 ((need_scan_psc &&
796 cfg80211_channel_is_psc(rdev_req->channels[i])) ||
797 !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
798 cfg80211_scan_req_add_chan(request,
799 rdev_req->channels[i],
800 false);
801 }
802 }
803
804 if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
805 goto skip;
806
807 list_for_each_entry(ap, &coloc_ap_list, list) {
808 bool found = false;
809 struct cfg80211_scan_6ghz_params *scan_6ghz_params =
810 &request->scan_6ghz_params[request->n_6ghz_params];
811 struct ieee80211_channel *chan =
812 ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
813
814 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
815 continue;
816
817 for (i = 0; i < rdev_req->n_channels; i++) {
818 if (rdev_req->channels[i] == chan)
819 found = true;
820 }
821
822 if (!found)
823 continue;
824
825 if (request->n_ssids > 0 &&
826 !cfg80211_find_ssid_match(ap, request))
827 continue;
828
829 cfg80211_scan_req_add_chan(request, chan, true);
830 memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
831 scan_6ghz_params->short_ssid = ap->short_ssid;
832 scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
833 scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
834
835 /*
836 * If a PSC channel is added to the scan and 'need_scan_psc' is
837 * set to false, then all the APs that the scan logic is
838 * interested with on the channel are collocated and thus there
839 * is no need to perform the initial PSC channel listen.
840 */
841 if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
842 scan_6ghz_params->psc_no_listen = true;
843
844 request->n_6ghz_params++;
845 }
846
847skip:
848 cfg80211_free_coloc_ap_list(&coloc_ap_list);
849
850 if (request->n_channels) {
851 struct cfg80211_scan_request *old = rdev->int_scan_req;
852 rdev->int_scan_req = request;
853
854 /*
855 * Add the ssids from the parent scan request to the new scan
856 * request, so the driver would be able to use them in its
857 * probe requests to discover hidden APs on PSC channels.
858 */
859 request->ssids = (void *)&request->channels[request->n_channels];
860 request->n_ssids = rdev_req->n_ssids;
861 memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) *
862 request->n_ssids);
863
864 /*
865 * If this scan follows a previous scan, save the scan start
866 * info from the first part of the scan
867 */
868 if (old)
869 rdev->int_scan_req->info = old->info;
870
871 err = rdev_scan(rdev, request);
872 if (err) {
873 rdev->int_scan_req = old;
874 kfree(request);
875 } else {
876 kfree(old);
877 }
878
879 return err;
880 }
881
882 kfree(request);
883 return -EINVAL;
884}
885
886int cfg80211_scan(struct cfg80211_registered_device *rdev)
887{
888 struct cfg80211_scan_request *request;
889 struct cfg80211_scan_request *rdev_req = rdev->scan_req;
890 u32 n_channels = 0, idx, i;
891
892 if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
893 return rdev_scan(rdev, rdev_req);
894
895 for (i = 0; i < rdev_req->n_channels; i++) {
896 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
897 n_channels++;
898 }
899
900 if (!n_channels)
901 return cfg80211_scan_6ghz(rdev);
902
903 request = kzalloc(struct_size(request, channels, n_channels),
904 GFP_KERNEL);
905 if (!request)
906 return -ENOMEM;
907
908 *request = *rdev_req;
909 request->n_channels = n_channels;
910
911 for (i = idx = 0; i < rdev_req->n_channels; i++) {
912 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
913 request->channels[idx++] = rdev_req->channels[i];
914 }
915
916 rdev_req->scan_6ghz = false;
917 rdev->int_scan_req = request;
918 return rdev_scan(rdev, request);
919}
920
921void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
922 bool send_message)
923{
924 struct cfg80211_scan_request *request, *rdev_req;
925 struct wireless_dev *wdev;
926 struct sk_buff *msg;
927#ifdef CONFIG_CFG80211_WEXT
928 union iwreq_data wrqu;
929#endif
930
931 lockdep_assert_held(&rdev->wiphy.mtx);
932
933 if (rdev->scan_msg) {
934 nl80211_send_scan_msg(rdev, rdev->scan_msg);
935 rdev->scan_msg = NULL;
936 return;
937 }
938
939 rdev_req = rdev->scan_req;
940 if (!rdev_req)
941 return;
942
943 wdev = rdev_req->wdev;
944 request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
945
946 if (wdev_running(wdev) &&
947 (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
948 !rdev_req->scan_6ghz && !request->info.aborted &&
949 !cfg80211_scan_6ghz(rdev))
950 return;
951
952 /*
953 * This must be before sending the other events!
954 * Otherwise, wpa_supplicant gets completely confused with
955 * wext events.
956 */
957 if (wdev->netdev)
958 cfg80211_sme_scan_done(wdev->netdev);
959
960 if (!request->info.aborted &&
961 request->flags & NL80211_SCAN_FLAG_FLUSH) {
962 /* flush entries from previous scans */
963 spin_lock_bh(&rdev->bss_lock);
964 __cfg80211_bss_expire(rdev, request->scan_start);
965 spin_unlock_bh(&rdev->bss_lock);
966 }
967
968 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
969
970#ifdef CONFIG_CFG80211_WEXT
971 if (wdev->netdev && !request->info.aborted) {
972 memset(&wrqu, 0, sizeof(wrqu));
973
974 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
975 }
976#endif
977
978 if (wdev->netdev)
979 dev_put(wdev->netdev);
980
981 kfree(rdev->int_scan_req);
982 rdev->int_scan_req = NULL;
983
984 kfree(rdev->scan_req);
985 rdev->scan_req = NULL;
986
987 if (!send_message)
988 rdev->scan_msg = msg;
989 else
990 nl80211_send_scan_msg(rdev, msg);
991}
992
993void __cfg80211_scan_done(struct work_struct *wk)
994{
995 struct cfg80211_registered_device *rdev;
996
997 rdev = container_of(wk, struct cfg80211_registered_device,
998 scan_done_wk);
999
1000 wiphy_lock(&rdev->wiphy);
1001 ___cfg80211_scan_done(rdev, true);
1002 wiphy_unlock(&rdev->wiphy);
1003}
1004
1005void cfg80211_scan_done(struct cfg80211_scan_request *request,
1006 struct cfg80211_scan_info *info)
1007{
1008 struct cfg80211_scan_info old_info = request->info;
1009
1010 trace_cfg80211_scan_done(request, info);
1011 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1012 request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1013
1014 request->info = *info;
1015
1016 /*
1017 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1018 * be of the first part. In such a case old_info.scan_start_tsf should
1019 * be non zero.
1020 */
1021 if (request->scan_6ghz && old_info.scan_start_tsf) {
1022 request->info.scan_start_tsf = old_info.scan_start_tsf;
1023 memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1024 sizeof(request->info.tsf_bssid));
1025 }
1026
1027 request->notified = true;
1028 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1029}
1030EXPORT_SYMBOL(cfg80211_scan_done);
1031
1032void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1033 struct cfg80211_sched_scan_request *req)
1034{
1035 lockdep_assert_held(&rdev->wiphy.mtx);
1036
1037 list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1038}
1039
1040static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1041 struct cfg80211_sched_scan_request *req)
1042{
1043 lockdep_assert_held(&rdev->wiphy.mtx);
1044
1045 list_del_rcu(&req->list);
1046 kfree_rcu(req, rcu_head);
1047}
1048
1049static struct cfg80211_sched_scan_request *
1050cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1051{
1052 struct cfg80211_sched_scan_request *pos;
1053
1054 list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1055 lockdep_is_held(&rdev->wiphy.mtx)) {
1056 if (pos->reqid == reqid)
1057 return pos;
1058 }
1059 return NULL;
1060}
1061
1062/*
1063 * Determines if a scheduled scan request can be handled. When a legacy
1064 * scheduled scan is running no other scheduled scan is allowed regardless
1065 * whether the request is for legacy or multi-support scan. When a multi-support
1066 * scheduled scan is running a request for legacy scan is not allowed. In this
1067 * case a request for multi-support scan can be handled if resources are
1068 * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1069 */
1070int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1071 bool want_multi)
1072{
1073 struct cfg80211_sched_scan_request *pos;
1074 int i = 0;
1075
1076 list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1077 /* request id zero means legacy in progress */
1078 if (!i && !pos->reqid)
1079 return -EINPROGRESS;
1080 i++;
1081 }
1082
1083 if (i) {
1084 /* no legacy allowed when multi request(s) are active */
1085 if (!want_multi)
1086 return -EINPROGRESS;
1087
1088 /* resource limit reached */
1089 if (i == rdev->wiphy.max_sched_scan_reqs)
1090 return -ENOSPC;
1091 }
1092 return 0;
1093}
1094
1095void cfg80211_sched_scan_results_wk(struct work_struct *work)
1096{
1097 struct cfg80211_registered_device *rdev;
1098 struct cfg80211_sched_scan_request *req, *tmp;
1099
1100 rdev = container_of(work, struct cfg80211_registered_device,
1101 sched_scan_res_wk);
1102
1103 wiphy_lock(&rdev->wiphy);
1104 list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1105 if (req->report_results) {
1106 req->report_results = false;
1107 if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1108 /* flush entries from previous scans */
1109 spin_lock_bh(&rdev->bss_lock);
1110 __cfg80211_bss_expire(rdev, req->scan_start);
1111 spin_unlock_bh(&rdev->bss_lock);
1112 req->scan_start = jiffies;
1113 }
1114 nl80211_send_sched_scan(req,
1115 NL80211_CMD_SCHED_SCAN_RESULTS);
1116 }
1117 }
1118 wiphy_unlock(&rdev->wiphy);
1119}
1120
1121void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1122{
1123 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1124 struct cfg80211_sched_scan_request *request;
1125
1126 trace_cfg80211_sched_scan_results(wiphy, reqid);
1127 /* ignore if we're not scanning */
1128
1129 rcu_read_lock();
1130 request = cfg80211_find_sched_scan_req(rdev, reqid);
1131 if (request) {
1132 request->report_results = true;
1133 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1134 }
1135 rcu_read_unlock();
1136}
1137EXPORT_SYMBOL(cfg80211_sched_scan_results);
1138
1139void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1140{
1141 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1142
1143 lockdep_assert_held(&wiphy->mtx);
1144
1145 trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1146
1147 __cfg80211_stop_sched_scan(rdev, reqid, true);
1148}
1149EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1150
1151void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1152{
1153 wiphy_lock(wiphy);
1154 cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1155 wiphy_unlock(wiphy);
1156}
1157EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1158
1159int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1160 struct cfg80211_sched_scan_request *req,
1161 bool driver_initiated)
1162{
1163 lockdep_assert_held(&rdev->wiphy.mtx);
1164
1165 if (!driver_initiated) {
1166 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1167 if (err)
1168 return err;
1169 }
1170
1171 nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1172
1173 cfg80211_del_sched_scan_req(rdev, req);
1174
1175 return 0;
1176}
1177
1178int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1179 u64 reqid, bool driver_initiated)
1180{
1181 struct cfg80211_sched_scan_request *sched_scan_req;
1182
1183 lockdep_assert_held(&rdev->wiphy.mtx);
1184
1185 sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1186 if (!sched_scan_req)
1187 return -ENOENT;
1188
1189 return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1190 driver_initiated);
1191}
1192
1193void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1194 unsigned long age_secs)
1195{
1196 struct cfg80211_internal_bss *bss;
1197 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1198
1199 spin_lock_bh(&rdev->bss_lock);
1200 list_for_each_entry(bss, &rdev->bss_list, list)
1201 bss->ts -= age_jiffies;
1202 spin_unlock_bh(&rdev->bss_lock);
1203}
1204
1205void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1206{
1207 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1208}
1209
1210void cfg80211_bss_flush(struct wiphy *wiphy)
1211{
1212 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1213
1214 spin_lock_bh(&rdev->bss_lock);
1215 __cfg80211_bss_expire(rdev, jiffies);
1216 spin_unlock_bh(&rdev->bss_lock);
1217}
1218EXPORT_SYMBOL(cfg80211_bss_flush);
1219
1220const struct element *
1221cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1222 const u8 *match, unsigned int match_len,
1223 unsigned int match_offset)
1224{
1225 const struct element *elem;
1226
1227 for_each_element_id(elem, eid, ies, len) {
1228 if (elem->datalen >= match_offset + match_len &&
1229 !memcmp(elem->data + match_offset, match, match_len))
1230 return elem;
1231 }
1232
1233 return NULL;
1234}
1235EXPORT_SYMBOL(cfg80211_find_elem_match);
1236
1237const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1238 const u8 *ies,
1239 unsigned int len)
1240{
1241 const struct element *elem;
1242 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1243 int match_len = (oui_type < 0) ? 3 : sizeof(match);
1244
1245 if (WARN_ON(oui_type > 0xff))
1246 return NULL;
1247
1248 elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1249 match, match_len, 0);
1250
1251 if (!elem || elem->datalen < 4)
1252 return NULL;
1253
1254 return elem;
1255}
1256EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1257
1258/**
1259 * enum bss_compare_mode - BSS compare mode
1260 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1261 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1262 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1263 */
1264enum bss_compare_mode {
1265 BSS_CMP_REGULAR,
1266 BSS_CMP_HIDE_ZLEN,
1267 BSS_CMP_HIDE_NUL,
1268};
1269
1270static int cmp_bss(struct cfg80211_bss *a,
1271 struct cfg80211_bss *b,
1272 enum bss_compare_mode mode)
1273{
1274 const struct cfg80211_bss_ies *a_ies, *b_ies;
1275 const u8 *ie1 = NULL;
1276 const u8 *ie2 = NULL;
1277 int i, r;
1278
1279 if (a->channel != b->channel)
1280 return b->channel->center_freq - a->channel->center_freq;
1281
1282 a_ies = rcu_access_pointer(a->ies);
1283 if (!a_ies)
1284 return -1;
1285 b_ies = rcu_access_pointer(b->ies);
1286 if (!b_ies)
1287 return 1;
1288
1289 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1290 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1291 a_ies->data, a_ies->len);
1292 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1293 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1294 b_ies->data, b_ies->len);
1295 if (ie1 && ie2) {
1296 int mesh_id_cmp;
1297
1298 if (ie1[1] == ie2[1])
1299 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1300 else
1301 mesh_id_cmp = ie2[1] - ie1[1];
1302
1303 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1304 a_ies->data, a_ies->len);
1305 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1306 b_ies->data, b_ies->len);
1307 if (ie1 && ie2) {
1308 if (mesh_id_cmp)
1309 return mesh_id_cmp;
1310 if (ie1[1] != ie2[1])
1311 return ie2[1] - ie1[1];
1312 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1313 }
1314 }
1315
1316 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1317 if (r)
1318 return r;
1319
1320 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1321 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1322
1323 if (!ie1 && !ie2)
1324 return 0;
1325
1326 /*
1327 * Note that with "hide_ssid", the function returns a match if
1328 * the already-present BSS ("b") is a hidden SSID beacon for
1329 * the new BSS ("a").
1330 */
1331
1332 /* sort missing IE before (left of) present IE */
1333 if (!ie1)
1334 return -1;
1335 if (!ie2)
1336 return 1;
1337
1338 switch (mode) {
1339 case BSS_CMP_HIDE_ZLEN:
1340 /*
1341 * In ZLEN mode we assume the BSS entry we're
1342 * looking for has a zero-length SSID. So if
1343 * the one we're looking at right now has that,
1344 * return 0. Otherwise, return the difference
1345 * in length, but since we're looking for the
1346 * 0-length it's really equivalent to returning
1347 * the length of the one we're looking at.
1348 *
1349 * No content comparison is needed as we assume
1350 * the content length is zero.
1351 */
1352 return ie2[1];
1353 case BSS_CMP_REGULAR:
1354 default:
1355 /* sort by length first, then by contents */
1356 if (ie1[1] != ie2[1])
1357 return ie2[1] - ie1[1];
1358 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1359 case BSS_CMP_HIDE_NUL:
1360 if (ie1[1] != ie2[1])
1361 return ie2[1] - ie1[1];
1362 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1363 for (i = 0; i < ie2[1]; i++)
1364 if (ie2[i + 2])
1365 return -1;
1366 return 0;
1367 }
1368}
1369
1370static bool cfg80211_bss_type_match(u16 capability,
1371 enum nl80211_band band,
1372 enum ieee80211_bss_type bss_type)
1373{
1374 bool ret = true;
1375 u16 mask, val;
1376
1377 if (bss_type == IEEE80211_BSS_TYPE_ANY)
1378 return ret;
1379
1380 if (band == NL80211_BAND_60GHZ) {
1381 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1382 switch (bss_type) {
1383 case IEEE80211_BSS_TYPE_ESS:
1384 val = WLAN_CAPABILITY_DMG_TYPE_AP;
1385 break;
1386 case IEEE80211_BSS_TYPE_PBSS:
1387 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1388 break;
1389 case IEEE80211_BSS_TYPE_IBSS:
1390 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1391 break;
1392 default:
1393 return false;
1394 }
1395 } else {
1396 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1397 switch (bss_type) {
1398 case IEEE80211_BSS_TYPE_ESS:
1399 val = WLAN_CAPABILITY_ESS;
1400 break;
1401 case IEEE80211_BSS_TYPE_IBSS:
1402 val = WLAN_CAPABILITY_IBSS;
1403 break;
1404 case IEEE80211_BSS_TYPE_MBSS:
1405 val = 0;
1406 break;
1407 default:
1408 return false;
1409 }
1410 }
1411
1412 ret = ((capability & mask) == val);
1413 return ret;
1414}
1415
1416/* Returned bss is reference counted and must be cleaned up appropriately. */
1417struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1418 struct ieee80211_channel *channel,
1419 const u8 *bssid,
1420 const u8 *ssid, size_t ssid_len,
1421 enum ieee80211_bss_type bss_type,
1422 enum ieee80211_privacy privacy)
1423{
1424 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1425 struct cfg80211_internal_bss *bss, *res = NULL;
1426 unsigned long now = jiffies;
1427 int bss_privacy;
1428
1429 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1430 privacy);
1431
1432 spin_lock_bh(&rdev->bss_lock);
1433
1434 list_for_each_entry(bss, &rdev->bss_list, list) {
1435 if (!cfg80211_bss_type_match(bss->pub.capability,
1436 bss->pub.channel->band, bss_type))
1437 continue;
1438
1439 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1440 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1441 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1442 continue;
1443 if (channel && bss->pub.channel != channel)
1444 continue;
1445 if (!is_valid_ether_addr(bss->pub.bssid))
1446 continue;
1447 /* Don't get expired BSS structs */
1448 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1449 !atomic_read(&bss->hold))
1450 continue;
1451 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1452 res = bss;
1453 bss_ref_get(rdev, res);
1454 break;
1455 }
1456 }
1457
1458 spin_unlock_bh(&rdev->bss_lock);
1459 if (!res)
1460 return NULL;
1461 trace_cfg80211_return_bss(&res->pub);
1462 return &res->pub;
1463}
1464EXPORT_SYMBOL(cfg80211_get_bss);
1465
1466static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1467 struct cfg80211_internal_bss *bss)
1468{
1469 struct rb_node **p = &rdev->bss_tree.rb_node;
1470 struct rb_node *parent = NULL;
1471 struct cfg80211_internal_bss *tbss;
1472 int cmp;
1473
1474 while (*p) {
1475 parent = *p;
1476 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1477
1478 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1479
1480 if (WARN_ON(!cmp)) {
1481 /* will sort of leak this BSS */
1482 return;
1483 }
1484
1485 if (cmp < 0)
1486 p = &(*p)->rb_left;
1487 else
1488 p = &(*p)->rb_right;
1489 }
1490
1491 rb_link_node(&bss->rbn, parent, p);
1492 rb_insert_color(&bss->rbn, &rdev->bss_tree);
1493}
1494
1495static struct cfg80211_internal_bss *
1496rb_find_bss(struct cfg80211_registered_device *rdev,
1497 struct cfg80211_internal_bss *res,
1498 enum bss_compare_mode mode)
1499{
1500 struct rb_node *n = rdev->bss_tree.rb_node;
1501 struct cfg80211_internal_bss *bss;
1502 int r;
1503
1504 while (n) {
1505 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1506 r = cmp_bss(&res->pub, &bss->pub, mode);
1507
1508 if (r == 0)
1509 return bss;
1510 else if (r < 0)
1511 n = n->rb_left;
1512 else
1513 n = n->rb_right;
1514 }
1515
1516 return NULL;
1517}
1518
1519static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1520 struct cfg80211_internal_bss *new)
1521{
1522 const struct cfg80211_bss_ies *ies;
1523 struct cfg80211_internal_bss *bss;
1524 const u8 *ie;
1525 int i, ssidlen;
1526 u8 fold = 0;
1527 u32 n_entries = 0;
1528
1529 ies = rcu_access_pointer(new->pub.beacon_ies);
1530 if (WARN_ON(!ies))
1531 return false;
1532
1533 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1534 if (!ie) {
1535 /* nothing to do */
1536 return true;
1537 }
1538
1539 ssidlen = ie[1];
1540 for (i = 0; i < ssidlen; i++)
1541 fold |= ie[2 + i];
1542
1543 if (fold) {
1544 /* not a hidden SSID */
1545 return true;
1546 }
1547
1548 /* This is the bad part ... */
1549
1550 list_for_each_entry(bss, &rdev->bss_list, list) {
1551 /*
1552 * we're iterating all the entries anyway, so take the
1553 * opportunity to validate the list length accounting
1554 */
1555 n_entries++;
1556
1557 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1558 continue;
1559 if (bss->pub.channel != new->pub.channel)
1560 continue;
1561 if (bss->pub.scan_width != new->pub.scan_width)
1562 continue;
1563 if (rcu_access_pointer(bss->pub.beacon_ies))
1564 continue;
1565 ies = rcu_access_pointer(bss->pub.ies);
1566 if (!ies)
1567 continue;
1568 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1569 if (!ie)
1570 continue;
1571 if (ssidlen && ie[1] != ssidlen)
1572 continue;
1573 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1574 continue;
1575 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1576 list_del(&bss->hidden_list);
1577 /* combine them */
1578 list_add(&bss->hidden_list, &new->hidden_list);
1579 bss->pub.hidden_beacon_bss = &new->pub;
1580 new->refcount += bss->refcount;
1581 rcu_assign_pointer(bss->pub.beacon_ies,
1582 new->pub.beacon_ies);
1583 }
1584
1585 WARN_ONCE(n_entries != rdev->bss_entries,
1586 "rdev bss entries[%d]/list[len:%d] corruption\n",
1587 rdev->bss_entries, n_entries);
1588
1589 return true;
1590}
1591
1592struct cfg80211_non_tx_bss {
1593 struct cfg80211_bss *tx_bss;
1594 u8 max_bssid_indicator;
1595 u8 bssid_index;
1596};
1597
1598static bool
1599cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1600 struct cfg80211_internal_bss *known,
1601 struct cfg80211_internal_bss *new,
1602 bool signal_valid)
1603{
1604 lockdep_assert_held(&rdev->bss_lock);
1605
1606 /* Update IEs */
1607 if (rcu_access_pointer(new->pub.proberesp_ies)) {
1608 const struct cfg80211_bss_ies *old;
1609
1610 old = rcu_access_pointer(known->pub.proberesp_ies);
1611
1612 rcu_assign_pointer(known->pub.proberesp_ies,
1613 new->pub.proberesp_ies);
1614 /* Override possible earlier Beacon frame IEs */
1615 rcu_assign_pointer(known->pub.ies,
1616 new->pub.proberesp_ies);
1617 if (old)
1618 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1619 } else if (rcu_access_pointer(new->pub.beacon_ies)) {
1620 const struct cfg80211_bss_ies *old;
1621 struct cfg80211_internal_bss *bss;
1622
1623 if (known->pub.hidden_beacon_bss &&
1624 !list_empty(&known->hidden_list)) {
1625 const struct cfg80211_bss_ies *f;
1626
1627 /* The known BSS struct is one of the probe
1628 * response members of a group, but we're
1629 * receiving a beacon (beacon_ies in the new
1630 * bss is used). This can only mean that the
1631 * AP changed its beacon from not having an
1632 * SSID to showing it, which is confusing so
1633 * drop this information.
1634 */
1635
1636 f = rcu_access_pointer(new->pub.beacon_ies);
1637 kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1638 return false;
1639 }
1640
1641 old = rcu_access_pointer(known->pub.beacon_ies);
1642
1643 rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1644
1645 /* Override IEs if they were from a beacon before */
1646 if (old == rcu_access_pointer(known->pub.ies))
1647 rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1648
1649 /* Assign beacon IEs to all sub entries */
1650 list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1651 const struct cfg80211_bss_ies *ies;
1652
1653 ies = rcu_access_pointer(bss->pub.beacon_ies);
1654 WARN_ON(ies != old);
1655
1656 rcu_assign_pointer(bss->pub.beacon_ies,
1657 new->pub.beacon_ies);
1658 }
1659
1660 if (old)
1661 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1662 }
1663
1664 known->pub.beacon_interval = new->pub.beacon_interval;
1665
1666 /* don't update the signal if beacon was heard on
1667 * adjacent channel.
1668 */
1669 if (signal_valid)
1670 known->pub.signal = new->pub.signal;
1671 known->pub.capability = new->pub.capability;
1672 known->ts = new->ts;
1673 known->ts_boottime = new->ts_boottime;
1674 known->parent_tsf = new->parent_tsf;
1675 known->pub.chains = new->pub.chains;
1676 memcpy(known->pub.chain_signal, new->pub.chain_signal,
1677 IEEE80211_MAX_CHAINS);
1678 ether_addr_copy(known->parent_bssid, new->parent_bssid);
1679 known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1680 known->pub.bssid_index = new->pub.bssid_index;
1681
1682 return true;
1683}
1684
1685/* Returned bss is reference counted and must be cleaned up appropriately. */
1686struct cfg80211_internal_bss *
1687cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1688 struct cfg80211_internal_bss *tmp,
1689 bool signal_valid, unsigned long ts)
1690{
1691 struct cfg80211_internal_bss *found = NULL;
1692
1693 if (WARN_ON(!tmp->pub.channel))
1694 return NULL;
1695
1696 tmp->ts = ts;
1697
1698 spin_lock_bh(&rdev->bss_lock);
1699
1700 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1701 spin_unlock_bh(&rdev->bss_lock);
1702 return NULL;
1703 }
1704
1705 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1706
1707 if (found) {
1708 if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1709 goto drop;
1710 } else {
1711 struct cfg80211_internal_bss *new;
1712 struct cfg80211_internal_bss *hidden;
1713 struct cfg80211_bss_ies *ies;
1714
1715 /*
1716 * create a copy -- the "res" variable that is passed in
1717 * is allocated on the stack since it's not needed in the
1718 * more common case of an update
1719 */
1720 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1721 GFP_ATOMIC);
1722 if (!new) {
1723 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1724 if (ies)
1725 kfree_rcu(ies, rcu_head);
1726 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1727 if (ies)
1728 kfree_rcu(ies, rcu_head);
1729 goto drop;
1730 }
1731 memcpy(new, tmp, sizeof(*new));
1732 new->refcount = 1;
1733 INIT_LIST_HEAD(&new->hidden_list);
1734 INIT_LIST_HEAD(&new->pub.nontrans_list);
1735
1736 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1737 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1738 if (!hidden)
1739 hidden = rb_find_bss(rdev, tmp,
1740 BSS_CMP_HIDE_NUL);
1741 if (hidden) {
1742 new->pub.hidden_beacon_bss = &hidden->pub;
1743 list_add(&new->hidden_list,
1744 &hidden->hidden_list);
1745 hidden->refcount++;
1746 rcu_assign_pointer(new->pub.beacon_ies,
1747 hidden->pub.beacon_ies);
1748 }
1749 } else {
1750 /*
1751 * Ok so we found a beacon, and don't have an entry. If
1752 * it's a beacon with hidden SSID, we might be in for an
1753 * expensive search for any probe responses that should
1754 * be grouped with this beacon for updates ...
1755 */
1756 if (!cfg80211_combine_bsses(rdev, new)) {
1757 bss_ref_put(rdev, new);
1758 goto drop;
1759 }
1760 }
1761
1762 if (rdev->bss_entries >= bss_entries_limit &&
1763 !cfg80211_bss_expire_oldest(rdev)) {
1764 bss_ref_put(rdev, new);
1765 goto drop;
1766 }
1767
1768 /* This must be before the call to bss_ref_get */
1769 if (tmp->pub.transmitted_bss) {
1770 struct cfg80211_internal_bss *pbss =
1771 container_of(tmp->pub.transmitted_bss,
1772 struct cfg80211_internal_bss,
1773 pub);
1774
1775 new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1776 bss_ref_get(rdev, pbss);
1777 }
1778
1779 list_add_tail(&new->list, &rdev->bss_list);
1780 rdev->bss_entries++;
1781 rb_insert_bss(rdev, new);
1782 found = new;
1783 }
1784
1785 rdev->bss_generation++;
1786 bss_ref_get(rdev, found);
1787 spin_unlock_bh(&rdev->bss_lock);
1788
1789 return found;
1790 drop:
1791 spin_unlock_bh(&rdev->bss_lock);
1792 return NULL;
1793}
1794
1795/*
1796 * Update RX channel information based on the available frame payload
1797 * information. This is mainly for the 2.4 GHz band where frames can be received
1798 * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1799 * element to indicate the current (transmitting) channel, but this might also
1800 * be needed on other bands if RX frequency does not match with the actual
1801 * operating channel of a BSS.
1802 */
1803static struct ieee80211_channel *
1804cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1805 struct ieee80211_channel *channel,
1806 enum nl80211_bss_scan_width scan_width)
1807{
1808 const u8 *tmp;
1809 u32 freq;
1810 int channel_number = -1;
1811 struct ieee80211_channel *alt_channel;
1812
1813 if (channel->band == NL80211_BAND_S1GHZ) {
1814 tmp = cfg80211_find_ie(WLAN_EID_S1G_OPERATION, ie, ielen);
1815 if (tmp && tmp[1] >= sizeof(struct ieee80211_s1g_oper_ie)) {
1816 struct ieee80211_s1g_oper_ie *s1gop = (void *)(tmp + 2);
1817
1818 channel_number = s1gop->primary_ch;
1819 }
1820 } else {
1821 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
1822 if (tmp && tmp[1] == 1) {
1823 channel_number = tmp[2];
1824 } else {
1825 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
1826 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
1827 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
1828
1829 channel_number = htop->primary_chan;
1830 }
1831 }
1832 }
1833
1834 if (channel_number < 0) {
1835 /* No channel information in frame payload */
1836 return channel;
1837 }
1838
1839 freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1840 alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1841 if (!alt_channel) {
1842 if (channel->band == NL80211_BAND_2GHZ) {
1843 /*
1844 * Better not allow unexpected channels when that could
1845 * be going beyond the 1-11 range (e.g., discovering
1846 * BSS on channel 12 when radio is configured for
1847 * channel 11.
1848 */
1849 return NULL;
1850 }
1851
1852 /* No match for the payload channel number - ignore it */
1853 return channel;
1854 }
1855
1856 if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1857 scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1858 /*
1859 * Ignore channel number in 5 and 10 MHz channels where there
1860 * may not be an n:1 or 1:n mapping between frequencies and
1861 * channel numbers.
1862 */
1863 return channel;
1864 }
1865
1866 /*
1867 * Use the channel determined through the payload channel number
1868 * instead of the RX channel reported by the driver.
1869 */
1870 if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1871 return NULL;
1872 return alt_channel;
1873}
1874
1875/* Returned bss is reference counted and must be cleaned up appropriately. */
1876static struct cfg80211_bss *
1877cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1878 struct cfg80211_inform_bss *data,
1879 enum cfg80211_bss_frame_type ftype,
1880 const u8 *bssid, u64 tsf, u16 capability,
1881 u16 beacon_interval, const u8 *ie, size_t ielen,
1882 struct cfg80211_non_tx_bss *non_tx_data,
1883 gfp_t gfp)
1884{
1885 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1886 struct cfg80211_bss_ies *ies;
1887 struct ieee80211_channel *channel;
1888 struct cfg80211_internal_bss tmp = {}, *res;
1889 int bss_type;
1890 bool signal_valid;
1891 unsigned long ts;
1892
1893 if (WARN_ON(!wiphy))
1894 return NULL;
1895
1896 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1897 (data->signal < 0 || data->signal > 100)))
1898 return NULL;
1899
1900 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1901 data->scan_width);
1902 if (!channel)
1903 return NULL;
1904
1905 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1906 tmp.pub.channel = channel;
1907 tmp.pub.scan_width = data->scan_width;
1908 tmp.pub.signal = data->signal;
1909 tmp.pub.beacon_interval = beacon_interval;
1910 tmp.pub.capability = capability;
1911 tmp.ts_boottime = data->boottime_ns;
1912 tmp.parent_tsf = data->parent_tsf;
1913 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1914
1915 if (non_tx_data) {
1916 tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1917 ts = bss_from_pub(non_tx_data->tx_bss)->ts;
1918 tmp.pub.bssid_index = non_tx_data->bssid_index;
1919 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1920 } else {
1921 ts = jiffies;
1922 }
1923
1924 /*
1925 * If we do not know here whether the IEs are from a Beacon or Probe
1926 * Response frame, we need to pick one of the options and only use it
1927 * with the driver that does not provide the full Beacon/Probe Response
1928 * frame. Use Beacon frame pointer to avoid indicating that this should
1929 * override the IEs pointer should we have received an earlier
1930 * indication of Probe Response data.
1931 */
1932 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1933 if (!ies)
1934 return NULL;
1935 ies->len = ielen;
1936 ies->tsf = tsf;
1937 ies->from_beacon = false;
1938 memcpy(ies->data, ie, ielen);
1939
1940 switch (ftype) {
1941 case CFG80211_BSS_FTYPE_BEACON:
1942 ies->from_beacon = true;
1943 fallthrough;
1944 case CFG80211_BSS_FTYPE_UNKNOWN:
1945 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1946 break;
1947 case CFG80211_BSS_FTYPE_PRESP:
1948 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1949 break;
1950 }
1951 rcu_assign_pointer(tmp.pub.ies, ies);
1952
1953 signal_valid = data->chan == channel;
1954 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
1955 if (!res)
1956 return NULL;
1957
1958 if (channel->band == NL80211_BAND_60GHZ) {
1959 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1960 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1961 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1962 regulatory_hint_found_beacon(wiphy, channel, gfp);
1963 } else {
1964 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1965 regulatory_hint_found_beacon(wiphy, channel, gfp);
1966 }
1967
1968 if (non_tx_data) {
1969 /* this is a nontransmitting bss, we need to add it to
1970 * transmitting bss' list if it is not there
1971 */
1972 if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
1973 &res->pub)) {
1974 if (__cfg80211_unlink_bss(rdev, res))
1975 rdev->bss_generation++;
1976 }
1977 }
1978
1979 trace_cfg80211_return_bss(&res->pub);
1980 /* cfg80211_bss_update gives us a referenced result */
1981 return &res->pub;
1982}
1983
1984static const struct element
1985*cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
1986 const struct element *mbssid_elem,
1987 const struct element *sub_elem)
1988{
1989 const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
1990 const struct element *next_mbssid;
1991 const struct element *next_sub;
1992
1993 next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
1994 mbssid_end,
1995 ielen - (mbssid_end - ie));
1996
1997 /*
1998 * If it is not the last subelement in current MBSSID IE or there isn't
1999 * a next MBSSID IE - profile is complete.
2000 */
2001 if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2002 !next_mbssid)
2003 return NULL;
2004
2005 /* For any length error, just return NULL */
2006
2007 if (next_mbssid->datalen < 4)
2008 return NULL;
2009
2010 next_sub = (void *)&next_mbssid->data[1];
2011
2012 if (next_mbssid->data + next_mbssid->datalen <
2013 next_sub->data + next_sub->datalen)
2014 return NULL;
2015
2016 if (next_sub->id != 0 || next_sub->datalen < 2)
2017 return NULL;
2018
2019 /*
2020 * Check if the first element in the next sub element is a start
2021 * of a new profile
2022 */
2023 return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2024 NULL : next_mbssid;
2025}
2026
2027size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2028 const struct element *mbssid_elem,
2029 const struct element *sub_elem,
2030 u8 *merged_ie, size_t max_copy_len)
2031{
2032 size_t copied_len = sub_elem->datalen;
2033 const struct element *next_mbssid;
2034
2035 if (sub_elem->datalen > max_copy_len)
2036 return 0;
2037
2038 memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2039
2040 while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2041 mbssid_elem,
2042 sub_elem))) {
2043 const struct element *next_sub = (void *)&next_mbssid->data[1];
2044
2045 if (copied_len + next_sub->datalen > max_copy_len)
2046 break;
2047 memcpy(merged_ie + copied_len, next_sub->data,
2048 next_sub->datalen);
2049 copied_len += next_sub->datalen;
2050 }
2051
2052 return copied_len;
2053}
2054EXPORT_SYMBOL(cfg80211_merge_profile);
2055
2056static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2057 struct cfg80211_inform_bss *data,
2058 enum cfg80211_bss_frame_type ftype,
2059 const u8 *bssid, u64 tsf,
2060 u16 beacon_interval, const u8 *ie,
2061 size_t ielen,
2062 struct cfg80211_non_tx_bss *non_tx_data,
2063 gfp_t gfp)
2064{
2065 const u8 *mbssid_index_ie;
2066 const struct element *elem, *sub;
2067 size_t new_ie_len;
2068 u8 new_bssid[ETH_ALEN];
2069 u8 *new_ie, *profile;
2070 u64 seen_indices = 0;
2071 u16 capability;
2072 struct cfg80211_bss *bss;
2073
2074 if (!non_tx_data)
2075 return;
2076 if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2077 return;
2078 if (!wiphy->support_mbssid)
2079 return;
2080 if (wiphy->support_only_he_mbssid &&
2081 !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2082 return;
2083
2084 new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2085 if (!new_ie)
2086 return;
2087
2088 profile = kmalloc(ielen, gfp);
2089 if (!profile)
2090 goto out;
2091
2092 for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
2093 if (elem->datalen < 4)
2094 continue;
2095 for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2096 u8 profile_len;
2097
2098 if (sub->id != 0 || sub->datalen < 4) {
2099 /* not a valid BSS profile */
2100 continue;
2101 }
2102
2103 if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2104 sub->data[1] != 2) {
2105 /* The first element within the Nontransmitted
2106 * BSSID Profile is not the Nontransmitted
2107 * BSSID Capability element.
2108 */
2109 continue;
2110 }
2111
2112 memset(profile, 0, ielen);
2113 profile_len = cfg80211_merge_profile(ie, ielen,
2114 elem,
2115 sub,
2116 profile,
2117 ielen);
2118
2119 /* found a Nontransmitted BSSID Profile */
2120 mbssid_index_ie = cfg80211_find_ie
2121 (WLAN_EID_MULTI_BSSID_IDX,
2122 profile, profile_len);
2123 if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2124 mbssid_index_ie[2] == 0 ||
2125 mbssid_index_ie[2] > 46) {
2126 /* No valid Multiple BSSID-Index element */
2127 continue;
2128 }
2129
2130 if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2131 /* We don't support legacy split of a profile */
2132 net_dbg_ratelimited("Partial info for BSSID index %d\n",
2133 mbssid_index_ie[2]);
2134
2135 seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2136
2137 non_tx_data->bssid_index = mbssid_index_ie[2];
2138 non_tx_data->max_bssid_indicator = elem->data[0];
2139
2140 cfg80211_gen_new_bssid(bssid,
2141 non_tx_data->max_bssid_indicator,
2142 non_tx_data->bssid_index,
2143 new_bssid);
2144 memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2145 new_ie_len = cfg80211_gen_new_ie(ie, ielen,
2146 profile,
2147 profile_len, new_ie,
2148 gfp);
2149 if (!new_ie_len)
2150 continue;
2151
2152 capability = get_unaligned_le16(profile + 2);
2153 bss = cfg80211_inform_single_bss_data(wiphy, data,
2154 ftype,
2155 new_bssid, tsf,
2156 capability,
2157 beacon_interval,
2158 new_ie,
2159 new_ie_len,
2160 non_tx_data,
2161 gfp);
2162 if (!bss)
2163 break;
2164 cfg80211_put_bss(wiphy, bss);
2165 }
2166 }
2167
2168out:
2169 kfree(new_ie);
2170 kfree(profile);
2171}
2172
2173struct cfg80211_bss *
2174cfg80211_inform_bss_data(struct wiphy *wiphy,
2175 struct cfg80211_inform_bss *data,
2176 enum cfg80211_bss_frame_type ftype,
2177 const u8 *bssid, u64 tsf, u16 capability,
2178 u16 beacon_interval, const u8 *ie, size_t ielen,
2179 gfp_t gfp)
2180{
2181 struct cfg80211_bss *res;
2182 struct cfg80211_non_tx_bss non_tx_data;
2183
2184 res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
2185 capability, beacon_interval, ie,
2186 ielen, NULL, gfp);
2187 if (!res)
2188 return NULL;
2189 non_tx_data.tx_bss = res;
2190 cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
2191 beacon_interval, ie, ielen, &non_tx_data,
2192 gfp);
2193 return res;
2194}
2195EXPORT_SYMBOL(cfg80211_inform_bss_data);
2196
2197static void
2198cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
2199 struct cfg80211_inform_bss *data,
2200 struct ieee80211_mgmt *mgmt, size_t len,
2201 struct cfg80211_non_tx_bss *non_tx_data,
2202 gfp_t gfp)
2203{
2204 enum cfg80211_bss_frame_type ftype;
2205 const u8 *ie = mgmt->u.probe_resp.variable;
2206 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2207 u.probe_resp.variable);
2208
2209 ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2210 CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2211
2212 cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
2213 le64_to_cpu(mgmt->u.probe_resp.timestamp),
2214 le16_to_cpu(mgmt->u.probe_resp.beacon_int),
2215 ie, ielen, non_tx_data, gfp);
2216}
2217
2218static void
2219cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
2220 struct cfg80211_bss *nontrans_bss,
2221 struct ieee80211_mgmt *mgmt, size_t len)
2222{
2223 u8 *ie, *new_ie, *pos;
2224 const u8 *nontrans_ssid, *trans_ssid, *mbssid;
2225 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2226 u.probe_resp.variable);
2227 size_t new_ie_len;
2228 struct cfg80211_bss_ies *new_ies;
2229 const struct cfg80211_bss_ies *old;
2230 u8 cpy_len;
2231
2232 lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
2233
2234 ie = mgmt->u.probe_resp.variable;
2235
2236 new_ie_len = ielen;
2237 trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
2238 if (!trans_ssid)
2239 return;
2240 new_ie_len -= trans_ssid[1];
2241 mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
2242 /*
2243 * It's not valid to have the MBSSID element before SSID
2244 * ignore if that happens - the code below assumes it is
2245 * after (while copying things inbetween).
2246 */
2247 if (!mbssid || mbssid < trans_ssid)
2248 return;
2249 new_ie_len -= mbssid[1];
2250
2251 nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
2252 if (!nontrans_ssid)
2253 return;
2254
2255 new_ie_len += nontrans_ssid[1];
2256
2257 /* generate new ie for nontrans BSS
2258 * 1. replace SSID with nontrans BSS' SSID
2259 * 2. skip MBSSID IE
2260 */
2261 new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
2262 if (!new_ie)
2263 return;
2264
2265 new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
2266 if (!new_ies)
2267 goto out_free;
2268
2269 pos = new_ie;
2270
2271 /* copy the nontransmitted SSID */
2272 cpy_len = nontrans_ssid[1] + 2;
2273 memcpy(pos, nontrans_ssid, cpy_len);
2274 pos += cpy_len;
2275 /* copy the IEs between SSID and MBSSID */
2276 cpy_len = trans_ssid[1] + 2;
2277 memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
2278 pos += (mbssid - (trans_ssid + cpy_len));
2279 /* copy the IEs after MBSSID */
2280 cpy_len = mbssid[1] + 2;
2281 memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
2282
2283 /* update ie */
2284 new_ies->len = new_ie_len;
2285 new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2286 new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
2287 memcpy(new_ies->data, new_ie, new_ie_len);
2288 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
2289 old = rcu_access_pointer(nontrans_bss->proberesp_ies);
2290 rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
2291 rcu_assign_pointer(nontrans_bss->ies, new_ies);
2292 if (old)
2293 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2294 } else {
2295 old = rcu_access_pointer(nontrans_bss->beacon_ies);
2296 rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
2297 rcu_assign_pointer(nontrans_bss->ies, new_ies);
2298 if (old)
2299 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2300 }
2301
2302out_free:
2303 kfree(new_ie);
2304}
2305
2306/* cfg80211_inform_bss_width_frame helper */
2307static struct cfg80211_bss *
2308cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2309 struct cfg80211_inform_bss *data,
2310 struct ieee80211_mgmt *mgmt, size_t len,
2311 gfp_t gfp)
2312{
2313 struct cfg80211_internal_bss tmp = {}, *res;
2314 struct cfg80211_bss_ies *ies;
2315 struct ieee80211_channel *channel;
2316 bool signal_valid;
2317 struct ieee80211_ext *ext = NULL;
2318 u8 *bssid, *variable;
2319 u16 capability, beacon_int;
2320 size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2321 u.probe_resp.variable);
2322 int bss_type;
2323
2324 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2325 offsetof(struct ieee80211_mgmt, u.beacon.variable));
2326
2327 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2328
2329 if (WARN_ON(!mgmt))
2330 return NULL;
2331
2332 if (WARN_ON(!wiphy))
2333 return NULL;
2334
2335 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2336 (data->signal < 0 || data->signal > 100)))
2337 return NULL;
2338
2339 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2340 ext = (void *) mgmt;
2341 min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2342 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2343 min_hdr_len = offsetof(struct ieee80211_ext,
2344 u.s1g_short_beacon.variable);
2345 }
2346
2347 if (WARN_ON(len < min_hdr_len))
2348 return NULL;
2349
2350 ielen = len - min_hdr_len;
2351 variable = mgmt->u.probe_resp.variable;
2352 if (ext) {
2353 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2354 variable = ext->u.s1g_short_beacon.variable;
2355 else
2356 variable = ext->u.s1g_beacon.variable;
2357 }
2358
2359 channel = cfg80211_get_bss_channel(wiphy, variable,
2360 ielen, data->chan, data->scan_width);
2361 if (!channel)
2362 return NULL;
2363
2364 if (ext) {
2365 const struct ieee80211_s1g_bcn_compat_ie *compat;
2366 const struct element *elem;
2367
2368 elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2369 variable, ielen);
2370 if (!elem)
2371 return NULL;
2372 if (elem->datalen < sizeof(*compat))
2373 return NULL;
2374 compat = (void *)elem->data;
2375 bssid = ext->u.s1g_beacon.sa;
2376 capability = le16_to_cpu(compat->compat_info);
2377 beacon_int = le16_to_cpu(compat->beacon_int);
2378 } else {
2379 bssid = mgmt->bssid;
2380 beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2381 capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2382 }
2383
2384 ies = kzalloc(sizeof(*ies) + ielen, gfp);
2385 if (!ies)
2386 return NULL;
2387 ies->len = ielen;
2388 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2389 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2390 ieee80211_is_s1g_beacon(mgmt->frame_control);
2391 memcpy(ies->data, variable, ielen);
2392
2393 if (ieee80211_is_probe_resp(mgmt->frame_control))
2394 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2395 else
2396 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2397 rcu_assign_pointer(tmp.pub.ies, ies);
2398
2399 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2400 tmp.pub.beacon_interval = beacon_int;
2401 tmp.pub.capability = capability;
2402 tmp.pub.channel = channel;
2403 tmp.pub.scan_width = data->scan_width;
2404 tmp.pub.signal = data->signal;
2405 tmp.ts_boottime = data->boottime_ns;
2406 tmp.parent_tsf = data->parent_tsf;
2407 tmp.pub.chains = data->chains;
2408 memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2409 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2410
2411 signal_valid = data->chan == channel;
2412 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
2413 jiffies);
2414 if (!res)
2415 return NULL;
2416
2417 if (channel->band == NL80211_BAND_60GHZ) {
2418 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2419 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2420 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2421 regulatory_hint_found_beacon(wiphy, channel, gfp);
2422 } else {
2423 if (res->pub.capability & WLAN_CAPABILITY_ESS)
2424 regulatory_hint_found_beacon(wiphy, channel, gfp);
2425 }
2426
2427 trace_cfg80211_return_bss(&res->pub);
2428 /* cfg80211_bss_update gives us a referenced result */
2429 return &res->pub;
2430}
2431
2432struct cfg80211_bss *
2433cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2434 struct cfg80211_inform_bss *data,
2435 struct ieee80211_mgmt *mgmt, size_t len,
2436 gfp_t gfp)
2437{
2438 struct cfg80211_bss *res, *tmp_bss;
2439 const u8 *ie = mgmt->u.probe_resp.variable;
2440 const struct cfg80211_bss_ies *ies1, *ies2;
2441 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2442 u.probe_resp.variable);
2443 struct cfg80211_non_tx_bss non_tx_data;
2444
2445 res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2446 len, gfp);
2447 if (!res || !wiphy->support_mbssid ||
2448 !cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2449 return res;
2450 if (wiphy->support_only_he_mbssid &&
2451 !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2452 return res;
2453
2454 non_tx_data.tx_bss = res;
2455 /* process each non-transmitting bss */
2456 cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
2457 &non_tx_data, gfp);
2458
2459 spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2460
2461 /* check if the res has other nontransmitting bss which is not
2462 * in MBSSID IE
2463 */
2464 ies1 = rcu_access_pointer(res->ies);
2465
2466 /* go through nontrans_list, if the timestamp of the BSS is
2467 * earlier than the timestamp of the transmitting BSS then
2468 * update it
2469 */
2470 list_for_each_entry(tmp_bss, &res->nontrans_list,
2471 nontrans_list) {
2472 ies2 = rcu_access_pointer(tmp_bss->ies);
2473 if (ies2->tsf < ies1->tsf)
2474 cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
2475 mgmt, len);
2476 }
2477 spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2478
2479 return res;
2480}
2481EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2482
2483void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2484{
2485 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2486 struct cfg80211_internal_bss *bss;
2487
2488 if (!pub)
2489 return;
2490
2491 bss = container_of(pub, struct cfg80211_internal_bss, pub);
2492
2493 spin_lock_bh(&rdev->bss_lock);
2494 bss_ref_get(rdev, bss);
2495 spin_unlock_bh(&rdev->bss_lock);
2496}
2497EXPORT_SYMBOL(cfg80211_ref_bss);
2498
2499void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2500{
2501 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2502 struct cfg80211_internal_bss *bss;
2503
2504 if (!pub)
2505 return;
2506
2507 bss = container_of(pub, struct cfg80211_internal_bss, pub);
2508
2509 spin_lock_bh(&rdev->bss_lock);
2510 bss_ref_put(rdev, bss);
2511 spin_unlock_bh(&rdev->bss_lock);
2512}
2513EXPORT_SYMBOL(cfg80211_put_bss);
2514
2515void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2516{
2517 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2518 struct cfg80211_internal_bss *bss, *tmp1;
2519 struct cfg80211_bss *nontrans_bss, *tmp;
2520
2521 if (WARN_ON(!pub))
2522 return;
2523
2524 bss = container_of(pub, struct cfg80211_internal_bss, pub);
2525
2526 spin_lock_bh(&rdev->bss_lock);
2527 if (list_empty(&bss->list))
2528 goto out;
2529
2530 list_for_each_entry_safe(nontrans_bss, tmp,
2531 &pub->nontrans_list,
2532 nontrans_list) {
2533 tmp1 = container_of(nontrans_bss,
2534 struct cfg80211_internal_bss, pub);
2535 if (__cfg80211_unlink_bss(rdev, tmp1))
2536 rdev->bss_generation++;
2537 }
2538
2539 if (__cfg80211_unlink_bss(rdev, bss))
2540 rdev->bss_generation++;
2541out:
2542 spin_unlock_bh(&rdev->bss_lock);
2543}
2544EXPORT_SYMBOL(cfg80211_unlink_bss);
2545
2546void cfg80211_bss_iter(struct wiphy *wiphy,
2547 struct cfg80211_chan_def *chandef,
2548 void (*iter)(struct wiphy *wiphy,
2549 struct cfg80211_bss *bss,
2550 void *data),
2551 void *iter_data)
2552{
2553 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2554 struct cfg80211_internal_bss *bss;
2555
2556 spin_lock_bh(&rdev->bss_lock);
2557
2558 list_for_each_entry(bss, &rdev->bss_list, list) {
2559 if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel))
2560 iter(wiphy, &bss->pub, iter_data);
2561 }
2562
2563 spin_unlock_bh(&rdev->bss_lock);
2564}
2565EXPORT_SYMBOL(cfg80211_bss_iter);
2566
2567void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
2568 struct ieee80211_channel *chan)
2569{
2570 struct wiphy *wiphy = wdev->wiphy;
2571 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2572 struct cfg80211_internal_bss *cbss = wdev->current_bss;
2573 struct cfg80211_internal_bss *new = NULL;
2574 struct cfg80211_internal_bss *bss;
2575 struct cfg80211_bss *nontrans_bss;
2576 struct cfg80211_bss *tmp;
2577
2578 spin_lock_bh(&rdev->bss_lock);
2579
2580 /*
2581 * Some APs use CSA also for bandwidth changes, i.e., without actually
2582 * changing the control channel, so no need to update in such a case.
2583 */
2584 if (cbss->pub.channel == chan)
2585 goto done;
2586
2587 /* use transmitting bss */
2588 if (cbss->pub.transmitted_bss)
2589 cbss = container_of(cbss->pub.transmitted_bss,
2590 struct cfg80211_internal_bss,
2591 pub);
2592
2593 cbss->pub.channel = chan;
2594
2595 list_for_each_entry(bss, &rdev->bss_list, list) {
2596 if (!cfg80211_bss_type_match(bss->pub.capability,
2597 bss->pub.channel->band,
2598 wdev->conn_bss_type))
2599 continue;
2600
2601 if (bss == cbss)
2602 continue;
2603
2604 if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
2605 new = bss;
2606 break;
2607 }
2608 }
2609
2610 if (new) {
2611 /* to save time, update IEs for transmitting bss only */
2612 if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
2613 new->pub.proberesp_ies = NULL;
2614 new->pub.beacon_ies = NULL;
2615 }
2616
2617 list_for_each_entry_safe(nontrans_bss, tmp,
2618 &new->pub.nontrans_list,
2619 nontrans_list) {
2620 bss = container_of(nontrans_bss,
2621 struct cfg80211_internal_bss, pub);
2622 if (__cfg80211_unlink_bss(rdev, bss))
2623 rdev->bss_generation++;
2624 }
2625
2626 WARN_ON(atomic_read(&new->hold));
2627 if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
2628 rdev->bss_generation++;
2629 }
2630
2631 rb_erase(&cbss->rbn, &rdev->bss_tree);
2632 rb_insert_bss(rdev, cbss);
2633 rdev->bss_generation++;
2634
2635 list_for_each_entry_safe(nontrans_bss, tmp,
2636 &cbss->pub.nontrans_list,
2637 nontrans_list) {
2638 bss = container_of(nontrans_bss,
2639 struct cfg80211_internal_bss, pub);
2640 bss->pub.channel = chan;
2641 rb_erase(&bss->rbn, &rdev->bss_tree);
2642 rb_insert_bss(rdev, bss);
2643 rdev->bss_generation++;
2644 }
2645
2646done:
2647 spin_unlock_bh(&rdev->bss_lock);
2648}
2649
2650#ifdef CONFIG_CFG80211_WEXT
2651static struct cfg80211_registered_device *
2652cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
2653{
2654 struct cfg80211_registered_device *rdev;
2655 struct net_device *dev;
2656
2657 ASSERT_RTNL();
2658
2659 dev = dev_get_by_index(net, ifindex);
2660 if (!dev)
2661 return ERR_PTR(-ENODEV);
2662 if (dev->ieee80211_ptr)
2663 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
2664 else
2665 rdev = ERR_PTR(-ENODEV);
2666 dev_put(dev);
2667 return rdev;
2668}
2669
2670int cfg80211_wext_siwscan(struct net_device *dev,
2671 struct iw_request_info *info,
2672 union iwreq_data *wrqu, char *extra)
2673{
2674 struct cfg80211_registered_device *rdev;
2675 struct wiphy *wiphy;
2676 struct iw_scan_req *wreq = NULL;
2677 struct cfg80211_scan_request *creq = NULL;
2678 int i, err, n_channels = 0;
2679 enum nl80211_band band;
2680
2681 if (!netif_running(dev))
2682 return -ENETDOWN;
2683
2684 if (wrqu->data.length == sizeof(struct iw_scan_req))
2685 wreq = (struct iw_scan_req *)extra;
2686
2687 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2688
2689 if (IS_ERR(rdev))
2690 return PTR_ERR(rdev);
2691
2692 if (rdev->scan_req || rdev->scan_msg) {
2693 err = -EBUSY;
2694 goto out;
2695 }
2696
2697 wiphy = &rdev->wiphy;
2698
2699 /* Determine number of channels, needed to allocate creq */
2700 if (wreq && wreq->num_channels)
2701 n_channels = wreq->num_channels;
2702 else
2703 n_channels = ieee80211_get_num_supported_channels(wiphy);
2704
2705 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2706 n_channels * sizeof(void *),
2707 GFP_ATOMIC);
2708 if (!creq) {
2709 err = -ENOMEM;
2710 goto out;
2711 }
2712
2713 creq->wiphy = wiphy;
2714 creq->wdev = dev->ieee80211_ptr;
2715 /* SSIDs come after channels */
2716 creq->ssids = (void *)&creq->channels[n_channels];
2717 creq->n_channels = n_channels;
2718 creq->n_ssids = 1;
2719 creq->scan_start = jiffies;
2720
2721 /* translate "Scan on frequencies" request */
2722 i = 0;
2723 for (band = 0; band < NUM_NL80211_BANDS; band++) {
2724 int j;
2725
2726 if (!wiphy->bands[band])
2727 continue;
2728
2729 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2730 /* ignore disabled channels */
2731 if (wiphy->bands[band]->channels[j].flags &
2732 IEEE80211_CHAN_DISABLED)
2733 continue;
2734
2735 /* If we have a wireless request structure and the
2736 * wireless request specifies frequencies, then search
2737 * for the matching hardware channel.
2738 */
2739 if (wreq && wreq->num_channels) {
2740 int k;
2741 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2742 for (k = 0; k < wreq->num_channels; k++) {
2743 struct iw_freq *freq =
2744 &wreq->channel_list[k];
2745 int wext_freq =
2746 cfg80211_wext_freq(freq);
2747
2748 if (wext_freq == wiphy_freq)
2749 goto wext_freq_found;
2750 }
2751 goto wext_freq_not_found;
2752 }
2753
2754 wext_freq_found:
2755 creq->channels[i] = &wiphy->bands[band]->channels[j];
2756 i++;
2757 wext_freq_not_found: ;
2758 }
2759 }
2760 /* No channels found? */
2761 if (!i) {
2762 err = -EINVAL;
2763 goto out;
2764 }
2765
2766 /* Set real number of channels specified in creq->channels[] */
2767 creq->n_channels = i;
2768
2769 /* translate "Scan for SSID" request */
2770 if (wreq) {
2771 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2772 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2773 err = -EINVAL;
2774 goto out;
2775 }
2776 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2777 creq->ssids[0].ssid_len = wreq->essid_len;
2778 }
2779 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2780 creq->n_ssids = 0;
2781 }
2782
2783 for (i = 0; i < NUM_NL80211_BANDS; i++)
2784 if (wiphy->bands[i])
2785 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2786
2787 eth_broadcast_addr(creq->bssid);
2788
2789 wiphy_lock(&rdev->wiphy);
2790
2791 rdev->scan_req = creq;
2792 err = rdev_scan(rdev, creq);
2793 if (err) {
2794 rdev->scan_req = NULL;
2795 /* creq will be freed below */
2796 } else {
2797 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2798 /* creq now owned by driver */
2799 creq = NULL;
2800 dev_hold(dev);
2801 }
2802 wiphy_unlock(&rdev->wiphy);
2803 out:
2804 kfree(creq);
2805 return err;
2806}
2807EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2808
2809static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2810 const struct cfg80211_bss_ies *ies,
2811 char *current_ev, char *end_buf)
2812{
2813 const u8 *pos, *end, *next;
2814 struct iw_event iwe;
2815
2816 if (!ies)
2817 return current_ev;
2818
2819 /*
2820 * If needed, fragment the IEs buffer (at IE boundaries) into short
2821 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2822 */
2823 pos = ies->data;
2824 end = pos + ies->len;
2825
2826 while (end - pos > IW_GENERIC_IE_MAX) {
2827 next = pos + 2 + pos[1];
2828 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2829 next = next + 2 + next[1];
2830
2831 memset(&iwe, 0, sizeof(iwe));
2832 iwe.cmd = IWEVGENIE;
2833 iwe.u.data.length = next - pos;
2834 current_ev = iwe_stream_add_point_check(info, current_ev,
2835 end_buf, &iwe,
2836 (void *)pos);
2837 if (IS_ERR(current_ev))
2838 return current_ev;
2839 pos = next;
2840 }
2841
2842 if (end > pos) {
2843 memset(&iwe, 0, sizeof(iwe));
2844 iwe.cmd = IWEVGENIE;
2845 iwe.u.data.length = end - pos;
2846 current_ev = iwe_stream_add_point_check(info, current_ev,
2847 end_buf, &iwe,
2848 (void *)pos);
2849 if (IS_ERR(current_ev))
2850 return current_ev;
2851 }
2852
2853 return current_ev;
2854}
2855
2856static char *
2857ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2858 struct cfg80211_internal_bss *bss, char *current_ev,
2859 char *end_buf)
2860{
2861 const struct cfg80211_bss_ies *ies;
2862 struct iw_event iwe;
2863 const u8 *ie;
2864 u8 buf[50];
2865 u8 *cfg, *p, *tmp;
2866 int rem, i, sig;
2867 bool ismesh = false;
2868
2869 memset(&iwe, 0, sizeof(iwe));
2870 iwe.cmd = SIOCGIWAP;
2871 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2872 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2873 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2874 IW_EV_ADDR_LEN);
2875 if (IS_ERR(current_ev))
2876 return current_ev;
2877
2878 memset(&iwe, 0, sizeof(iwe));
2879 iwe.cmd = SIOCGIWFREQ;
2880 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2881 iwe.u.freq.e = 0;
2882 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2883 IW_EV_FREQ_LEN);
2884 if (IS_ERR(current_ev))
2885 return current_ev;
2886
2887 memset(&iwe, 0, sizeof(iwe));
2888 iwe.cmd = SIOCGIWFREQ;
2889 iwe.u.freq.m = bss->pub.channel->center_freq;
2890 iwe.u.freq.e = 6;
2891 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2892 IW_EV_FREQ_LEN);
2893 if (IS_ERR(current_ev))
2894 return current_ev;
2895
2896 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2897 memset(&iwe, 0, sizeof(iwe));
2898 iwe.cmd = IWEVQUAL;
2899 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2900 IW_QUAL_NOISE_INVALID |
2901 IW_QUAL_QUAL_UPDATED;
2902 switch (wiphy->signal_type) {
2903 case CFG80211_SIGNAL_TYPE_MBM:
2904 sig = bss->pub.signal / 100;
2905 iwe.u.qual.level = sig;
2906 iwe.u.qual.updated |= IW_QUAL_DBM;
2907 if (sig < -110) /* rather bad */
2908 sig = -110;
2909 else if (sig > -40) /* perfect */
2910 sig = -40;
2911 /* will give a range of 0 .. 70 */
2912 iwe.u.qual.qual = sig + 110;
2913 break;
2914 case CFG80211_SIGNAL_TYPE_UNSPEC:
2915 iwe.u.qual.level = bss->pub.signal;
2916 /* will give range 0 .. 100 */
2917 iwe.u.qual.qual = bss->pub.signal;
2918 break;
2919 default:
2920 /* not reached */
2921 break;
2922 }
2923 current_ev = iwe_stream_add_event_check(info, current_ev,
2924 end_buf, &iwe,
2925 IW_EV_QUAL_LEN);
2926 if (IS_ERR(current_ev))
2927 return current_ev;
2928 }
2929
2930 memset(&iwe, 0, sizeof(iwe));
2931 iwe.cmd = SIOCGIWENCODE;
2932 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
2933 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
2934 else
2935 iwe.u.data.flags = IW_ENCODE_DISABLED;
2936 iwe.u.data.length = 0;
2937 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2938 &iwe, "");
2939 if (IS_ERR(current_ev))
2940 return current_ev;
2941
2942 rcu_read_lock();
2943 ies = rcu_dereference(bss->pub.ies);
2944 rem = ies->len;
2945 ie = ies->data;
2946
2947 while (rem >= 2) {
2948 /* invalid data */
2949 if (ie[1] > rem - 2)
2950 break;
2951
2952 switch (ie[0]) {
2953 case WLAN_EID_SSID:
2954 memset(&iwe, 0, sizeof(iwe));
2955 iwe.cmd = SIOCGIWESSID;
2956 iwe.u.data.length = ie[1];
2957 iwe.u.data.flags = 1;
2958 current_ev = iwe_stream_add_point_check(info,
2959 current_ev,
2960 end_buf, &iwe,
2961 (u8 *)ie + 2);
2962 if (IS_ERR(current_ev))
2963 goto unlock;
2964 break;
2965 case WLAN_EID_MESH_ID:
2966 memset(&iwe, 0, sizeof(iwe));
2967 iwe.cmd = SIOCGIWESSID;
2968 iwe.u.data.length = ie[1];
2969 iwe.u.data.flags = 1;
2970 current_ev = iwe_stream_add_point_check(info,
2971 current_ev,
2972 end_buf, &iwe,
2973 (u8 *)ie + 2);
2974 if (IS_ERR(current_ev))
2975 goto unlock;
2976 break;
2977 case WLAN_EID_MESH_CONFIG:
2978 ismesh = true;
2979 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
2980 break;
2981 cfg = (u8 *)ie + 2;
2982 memset(&iwe, 0, sizeof(iwe));
2983 iwe.cmd = IWEVCUSTOM;
2984 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
2985 "0x%02X", cfg[0]);
2986 iwe.u.data.length = strlen(buf);
2987 current_ev = iwe_stream_add_point_check(info,
2988 current_ev,
2989 end_buf,
2990 &iwe, buf);
2991 if (IS_ERR(current_ev))
2992 goto unlock;
2993 sprintf(buf, "Path Selection Metric ID: 0x%02X",
2994 cfg[1]);
2995 iwe.u.data.length = strlen(buf);
2996 current_ev = iwe_stream_add_point_check(info,
2997 current_ev,
2998 end_buf,
2999 &iwe, buf);
3000 if (IS_ERR(current_ev))
3001 goto unlock;
3002 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3003 cfg[2]);
3004 iwe.u.data.length = strlen(buf);
3005 current_ev = iwe_stream_add_point_check(info,
3006 current_ev,
3007 end_buf,
3008 &iwe, buf);
3009 if (IS_ERR(current_ev))
3010 goto unlock;
3011 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3012 iwe.u.data.length = strlen(buf);
3013 current_ev = iwe_stream_add_point_check(info,
3014 current_ev,
3015 end_buf,
3016 &iwe, buf);
3017 if (IS_ERR(current_ev))
3018 goto unlock;
3019 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3020 iwe.u.data.length = strlen(buf);
3021 current_ev = iwe_stream_add_point_check(info,
3022 current_ev,
3023 end_buf,
3024 &iwe, buf);
3025 if (IS_ERR(current_ev))
3026 goto unlock;
3027 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3028 iwe.u.data.length = strlen(buf);
3029 current_ev = iwe_stream_add_point_check(info,
3030 current_ev,
3031 end_buf,
3032 &iwe, buf);
3033 if (IS_ERR(current_ev))
3034 goto unlock;
3035 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3036 iwe.u.data.length = strlen(buf);
3037 current_ev = iwe_stream_add_point_check(info,
3038 current_ev,
3039 end_buf,
3040 &iwe, buf);
3041 if (IS_ERR(current_ev))
3042 goto unlock;
3043 break;
3044 case WLAN_EID_SUPP_RATES:
3045 case WLAN_EID_EXT_SUPP_RATES:
3046 /* display all supported rates in readable format */
3047 p = current_ev + iwe_stream_lcp_len(info);
3048
3049 memset(&iwe, 0, sizeof(iwe));
3050 iwe.cmd = SIOCGIWRATE;
3051 /* Those two flags are ignored... */
3052 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3053
3054 for (i = 0; i < ie[1]; i++) {
3055 iwe.u.bitrate.value =
3056 ((ie[i + 2] & 0x7f) * 500000);
3057 tmp = p;
3058 p = iwe_stream_add_value(info, current_ev, p,
3059 end_buf, &iwe,
3060 IW_EV_PARAM_LEN);
3061 if (p == tmp) {
3062 current_ev = ERR_PTR(-E2BIG);
3063 goto unlock;
3064 }
3065 }
3066 current_ev = p;
3067 break;
3068 }
3069 rem -= ie[1] + 2;
3070 ie += ie[1] + 2;
3071 }
3072
3073 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3074 ismesh) {
3075 memset(&iwe, 0, sizeof(iwe));
3076 iwe.cmd = SIOCGIWMODE;
3077 if (ismesh)
3078 iwe.u.mode = IW_MODE_MESH;
3079 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3080 iwe.u.mode = IW_MODE_MASTER;
3081 else
3082 iwe.u.mode = IW_MODE_ADHOC;
3083 current_ev = iwe_stream_add_event_check(info, current_ev,
3084 end_buf, &iwe,
3085 IW_EV_UINT_LEN);
3086 if (IS_ERR(current_ev))
3087 goto unlock;
3088 }
3089
3090 memset(&iwe, 0, sizeof(iwe));
3091 iwe.cmd = IWEVCUSTOM;
3092 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3093 iwe.u.data.length = strlen(buf);
3094 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3095 &iwe, buf);
3096 if (IS_ERR(current_ev))
3097 goto unlock;
3098 memset(&iwe, 0, sizeof(iwe));
3099 iwe.cmd = IWEVCUSTOM;
3100 sprintf(buf, " Last beacon: %ums ago",
3101 elapsed_jiffies_msecs(bss->ts));
3102 iwe.u.data.length = strlen(buf);
3103 current_ev = iwe_stream_add_point_check(info, current_ev,
3104 end_buf, &iwe, buf);
3105 if (IS_ERR(current_ev))
3106 goto unlock;
3107
3108 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3109
3110 unlock:
3111 rcu_read_unlock();
3112 return current_ev;
3113}
3114
3115
3116static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3117 struct iw_request_info *info,
3118 char *buf, size_t len)
3119{
3120 char *current_ev = buf;
3121 char *end_buf = buf + len;
3122 struct cfg80211_internal_bss *bss;
3123 int err = 0;
3124
3125 spin_lock_bh(&rdev->bss_lock);
3126 cfg80211_bss_expire(rdev);
3127
3128 list_for_each_entry(bss, &rdev->bss_list, list) {
3129 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3130 err = -E2BIG;
3131 break;
3132 }
3133 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3134 current_ev, end_buf);
3135 if (IS_ERR(current_ev)) {
3136 err = PTR_ERR(current_ev);
3137 break;
3138 }
3139 }
3140 spin_unlock_bh(&rdev->bss_lock);
3141
3142 if (err)
3143 return err;
3144 return current_ev - buf;
3145}
3146
3147
3148int cfg80211_wext_giwscan(struct net_device *dev,
3149 struct iw_request_info *info,
3150 struct iw_point *data, char *extra)
3151{
3152 struct cfg80211_registered_device *rdev;
3153 int res;
3154
3155 if (!netif_running(dev))
3156 return -ENETDOWN;
3157
3158 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3159
3160 if (IS_ERR(rdev))
3161 return PTR_ERR(rdev);
3162
3163 if (rdev->scan_req || rdev->scan_msg)
3164 return -EAGAIN;
3165
3166 res = ieee80211_scan_results(rdev, info, extra, data->length);
3167 data->length = 0;
3168 if (res >= 0) {
3169 data->length = res;
3170 res = 0;
3171 }
3172
3173 return res;
3174}
3175EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3176#endif
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) 2018-2022 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 */
72static int bss_entries_limit = 1000;
73module_param(bss_entries_limit, int, 0644);
74MODULE_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 */
100struct cfg80211_colocated_ap {
101 struct list_head list;
102 u8 bssid[ETH_ALEN];
103 u8 ssid[IEEE80211_MAX_SSID_LEN];
104 size_t ssid_len;
105 u32 short_ssid;
106 u32 center_freq;
107 u8 unsolicited_probe:1,
108 oct_recommended:1,
109 same_ssid:1,
110 multi_bss:1,
111 transmitted_bssid:1,
112 colocated_ess:1,
113 short_ssid_valid:1;
114};
115
116static void bss_free(struct cfg80211_internal_bss *bss)
117{
118 struct cfg80211_bss_ies *ies;
119
120 if (WARN_ON(atomic_read(&bss->hold)))
121 return;
122
123 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
124 if (ies && !bss->pub.hidden_beacon_bss)
125 kfree_rcu(ies, rcu_head);
126 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
127 if (ies)
128 kfree_rcu(ies, rcu_head);
129
130 /*
131 * This happens when the module is removed, it doesn't
132 * really matter any more save for completeness
133 */
134 if (!list_empty(&bss->hidden_list))
135 list_del(&bss->hidden_list);
136
137 kfree(bss);
138}
139
140static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
141 struct cfg80211_internal_bss *bss)
142{
143 lockdep_assert_held(&rdev->bss_lock);
144
145 bss->refcount++;
146
147 if (bss->pub.hidden_beacon_bss)
148 bss_from_pub(bss->pub.hidden_beacon_bss)->refcount++;
149
150 if (bss->pub.transmitted_bss)
151 bss_from_pub(bss->pub.transmitted_bss)->refcount++;
152}
153
154static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
155 struct cfg80211_internal_bss *bss)
156{
157 lockdep_assert_held(&rdev->bss_lock);
158
159 if (bss->pub.hidden_beacon_bss) {
160 struct cfg80211_internal_bss *hbss;
161
162 hbss = bss_from_pub(bss->pub.hidden_beacon_bss);
163 hbss->refcount--;
164 if (hbss->refcount == 0)
165 bss_free(hbss);
166 }
167
168 if (bss->pub.transmitted_bss) {
169 struct cfg80211_internal_bss *tbss;
170
171 tbss = bss_from_pub(bss->pub.transmitted_bss);
172 tbss->refcount--;
173 if (tbss->refcount == 0)
174 bss_free(tbss);
175 }
176
177 bss->refcount--;
178 if (bss->refcount == 0)
179 bss_free(bss);
180}
181
182static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
183 struct cfg80211_internal_bss *bss)
184{
185 lockdep_assert_held(&rdev->bss_lock);
186
187 if (!list_empty(&bss->hidden_list)) {
188 /*
189 * don't remove the beacon entry if it has
190 * probe responses associated with it
191 */
192 if (!bss->pub.hidden_beacon_bss)
193 return false;
194 /*
195 * if it's a probe response entry break its
196 * link to the other entries in the group
197 */
198 list_del_init(&bss->hidden_list);
199 }
200
201 list_del_init(&bss->list);
202 list_del_init(&bss->pub.nontrans_list);
203 rb_erase(&bss->rbn, &rdev->bss_tree);
204 rdev->bss_entries--;
205 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
206 "rdev bss entries[%d]/list[empty:%d] corruption\n",
207 rdev->bss_entries, list_empty(&rdev->bss_list));
208 bss_ref_put(rdev, bss);
209 return true;
210}
211
212bool cfg80211_is_element_inherited(const struct element *elem,
213 const struct element *non_inherit_elem)
214{
215 u8 id_len, ext_id_len, i, loop_len, id;
216 const u8 *list;
217
218 if (elem->id == WLAN_EID_MULTIPLE_BSSID)
219 return false;
220
221 if (!non_inherit_elem || non_inherit_elem->datalen < 2)
222 return true;
223
224 /*
225 * non inheritance element format is:
226 * ext ID (56) | IDs list len | list | extension IDs list len | list
227 * Both lists are optional. Both lengths are mandatory.
228 * This means valid length is:
229 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
230 */
231 id_len = non_inherit_elem->data[1];
232 if (non_inherit_elem->datalen < 3 + id_len)
233 return true;
234
235 ext_id_len = non_inherit_elem->data[2 + id_len];
236 if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
237 return true;
238
239 if (elem->id == WLAN_EID_EXTENSION) {
240 if (!ext_id_len)
241 return true;
242 loop_len = ext_id_len;
243 list = &non_inherit_elem->data[3 + id_len];
244 id = elem->data[0];
245 } else {
246 if (!id_len)
247 return true;
248 loop_len = id_len;
249 list = &non_inherit_elem->data[2];
250 id = elem->id;
251 }
252
253 for (i = 0; i < loop_len; i++) {
254 if (list[i] == id)
255 return false;
256 }
257
258 return true;
259}
260EXPORT_SYMBOL(cfg80211_is_element_inherited);
261
262static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
263 const u8 *subelement, size_t subie_len,
264 u8 *new_ie, gfp_t gfp)
265{
266 u8 *pos, *tmp;
267 const u8 *tmp_old, *tmp_new;
268 const struct element *non_inherit_elem;
269 u8 *sub_copy;
270
271 /* copy subelement as we need to change its content to
272 * mark an ie after it is processed.
273 */
274 sub_copy = kmemdup(subelement, subie_len, gfp);
275 if (!sub_copy)
276 return 0;
277
278 pos = &new_ie[0];
279
280 /* set new ssid */
281 tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
282 if (tmp_new) {
283 memcpy(pos, tmp_new, tmp_new[1] + 2);
284 pos += (tmp_new[1] + 2);
285 }
286
287 /* get non inheritance list if exists */
288 non_inherit_elem =
289 cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
290 sub_copy, subie_len);
291
292 /* go through IEs in ie (skip SSID) and subelement,
293 * merge them into new_ie
294 */
295 tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
296 tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
297
298 while (tmp_old + 2 - ie <= ielen &&
299 tmp_old + tmp_old[1] + 2 - ie <= ielen) {
300 if (tmp_old[0] == 0) {
301 tmp_old++;
302 continue;
303 }
304
305 if (tmp_old[0] == WLAN_EID_EXTENSION)
306 tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
307 subie_len);
308 else
309 tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
310 subie_len);
311
312 if (!tmp) {
313 const struct element *old_elem = (void *)tmp_old;
314
315 /* ie in old ie but not in subelement */
316 if (cfg80211_is_element_inherited(old_elem,
317 non_inherit_elem)) {
318 memcpy(pos, tmp_old, tmp_old[1] + 2);
319 pos += tmp_old[1] + 2;
320 }
321 } else {
322 /* ie in transmitting ie also in subelement,
323 * copy from subelement and flag the ie in subelement
324 * as copied (by setting eid field to WLAN_EID_SSID,
325 * which is skipped anyway).
326 * For vendor ie, compare OUI + type + subType to
327 * determine if they are the same ie.
328 */
329 if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
330 if (tmp_old[1] >= 5 && tmp[1] >= 5 &&
331 !memcmp(tmp_old + 2, tmp + 2, 5)) {
332 /* same vendor ie, copy from
333 * subelement
334 */
335 memcpy(pos, tmp, tmp[1] + 2);
336 pos += tmp[1] + 2;
337 tmp[0] = WLAN_EID_SSID;
338 } else {
339 memcpy(pos, tmp_old, tmp_old[1] + 2);
340 pos += tmp_old[1] + 2;
341 }
342 } else {
343 /* copy ie from subelement into new ie */
344 memcpy(pos, tmp, tmp[1] + 2);
345 pos += tmp[1] + 2;
346 tmp[0] = WLAN_EID_SSID;
347 }
348 }
349
350 if (tmp_old + tmp_old[1] + 2 - ie == ielen)
351 break;
352
353 tmp_old += tmp_old[1] + 2;
354 }
355
356 /* go through subelement again to check if there is any ie not
357 * copied to new ie, skip ssid, capability, bssid-index ie
358 */
359 tmp_new = sub_copy;
360 while (tmp_new + 2 - sub_copy <= subie_len &&
361 tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
362 if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
363 tmp_new[0] == WLAN_EID_SSID)) {
364 memcpy(pos, tmp_new, tmp_new[1] + 2);
365 pos += tmp_new[1] + 2;
366 }
367 if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
368 break;
369 tmp_new += tmp_new[1] + 2;
370 }
371
372 kfree(sub_copy);
373 return pos - new_ie;
374}
375
376static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
377 const u8 *ssid, size_t ssid_len)
378{
379 const struct cfg80211_bss_ies *ies;
380 const struct element *ssid_elem;
381
382 if (bssid && !ether_addr_equal(a->bssid, bssid))
383 return false;
384
385 if (!ssid)
386 return true;
387
388 ies = rcu_access_pointer(a->ies);
389 if (!ies)
390 return false;
391 ssid_elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
392 if (!ssid_elem)
393 return false;
394 if (ssid_elem->datalen != ssid_len)
395 return false;
396 return memcmp(ssid_elem->data, ssid, ssid_len) == 0;
397}
398
399static int
400cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
401 struct cfg80211_bss *nontrans_bss)
402{
403 const struct element *ssid_elem;
404 struct cfg80211_bss *bss = NULL;
405
406 rcu_read_lock();
407 ssid_elem = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
408 if (!ssid_elem) {
409 rcu_read_unlock();
410 return -EINVAL;
411 }
412
413 /* check if nontrans_bss is in the list */
414 list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
415 if (is_bss(bss, nontrans_bss->bssid, ssid_elem->data,
416 ssid_elem->datalen)) {
417 rcu_read_unlock();
418 return 0;
419 }
420 }
421
422 rcu_read_unlock();
423
424 /*
425 * This is a bit weird - it's not on the list, but already on another
426 * one! The only way that could happen is if there's some BSSID/SSID
427 * shared by multiple APs in their multi-BSSID profiles, potentially
428 * with hidden SSID mixed in ... ignore it.
429 */
430 if (!list_empty(&nontrans_bss->nontrans_list))
431 return -EINVAL;
432
433 /* add to the list */
434 list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
435 return 0;
436}
437
438static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
439 unsigned long expire_time)
440{
441 struct cfg80211_internal_bss *bss, *tmp;
442 bool expired = false;
443
444 lockdep_assert_held(&rdev->bss_lock);
445
446 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
447 if (atomic_read(&bss->hold))
448 continue;
449 if (!time_after(expire_time, bss->ts))
450 continue;
451
452 if (__cfg80211_unlink_bss(rdev, bss))
453 expired = true;
454 }
455
456 if (expired)
457 rdev->bss_generation++;
458}
459
460static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
461{
462 struct cfg80211_internal_bss *bss, *oldest = NULL;
463 bool ret;
464
465 lockdep_assert_held(&rdev->bss_lock);
466
467 list_for_each_entry(bss, &rdev->bss_list, list) {
468 if (atomic_read(&bss->hold))
469 continue;
470
471 if (!list_empty(&bss->hidden_list) &&
472 !bss->pub.hidden_beacon_bss)
473 continue;
474
475 if (oldest && time_before(oldest->ts, bss->ts))
476 continue;
477 oldest = bss;
478 }
479
480 if (WARN_ON(!oldest))
481 return false;
482
483 /*
484 * The callers make sure to increase rdev->bss_generation if anything
485 * gets removed (and a new entry added), so there's no need to also do
486 * it here.
487 */
488
489 ret = __cfg80211_unlink_bss(rdev, oldest);
490 WARN_ON(!ret);
491 return ret;
492}
493
494static u8 cfg80211_parse_bss_param(u8 data,
495 struct cfg80211_colocated_ap *coloc_ap)
496{
497 coloc_ap->oct_recommended =
498 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
499 coloc_ap->same_ssid =
500 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
501 coloc_ap->multi_bss =
502 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
503 coloc_ap->transmitted_bssid =
504 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
505 coloc_ap->unsolicited_probe =
506 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
507 coloc_ap->colocated_ess =
508 u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
509
510 return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
511}
512
513static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
514 const struct element **elem, u32 *s_ssid)
515{
516
517 *elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
518 if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
519 return -EINVAL;
520
521 *s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
522 return 0;
523}
524
525static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
526{
527 struct cfg80211_colocated_ap *ap, *tmp_ap;
528
529 list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
530 list_del(&ap->list);
531 kfree(ap);
532 }
533}
534
535static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
536 const u8 *pos, u8 length,
537 const struct element *ssid_elem,
538 int s_ssid_tmp)
539{
540 /* skip the TBTT offset */
541 pos++;
542
543 memcpy(entry->bssid, pos, ETH_ALEN);
544 pos += ETH_ALEN;
545
546 if (length >= IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) {
547 memcpy(&entry->short_ssid, pos,
548 sizeof(entry->short_ssid));
549 entry->short_ssid_valid = true;
550 pos += 4;
551 }
552
553 /* skip non colocated APs */
554 if (!cfg80211_parse_bss_param(*pos, entry))
555 return -EINVAL;
556 pos++;
557
558 if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) {
559 /*
560 * no information about the short ssid. Consider the entry valid
561 * for now. It would later be dropped in case there are explicit
562 * SSIDs that need to be matched
563 */
564 if (!entry->same_ssid)
565 return 0;
566 }
567
568 if (entry->same_ssid) {
569 entry->short_ssid = s_ssid_tmp;
570 entry->short_ssid_valid = true;
571
572 /*
573 * This is safe because we validate datalen in
574 * cfg80211_parse_colocated_ap(), before calling this
575 * function.
576 */
577 memcpy(&entry->ssid, &ssid_elem->data,
578 ssid_elem->datalen);
579 entry->ssid_len = ssid_elem->datalen;
580 }
581 return 0;
582}
583
584static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
585 struct list_head *list)
586{
587 struct ieee80211_neighbor_ap_info *ap_info;
588 const struct element *elem, *ssid_elem;
589 const u8 *pos, *end;
590 u32 s_ssid_tmp;
591 int n_coloc = 0, ret;
592 LIST_HEAD(ap_list);
593
594 elem = cfg80211_find_elem(WLAN_EID_REDUCED_NEIGHBOR_REPORT, ies->data,
595 ies->len);
596 if (!elem)
597 return 0;
598
599 pos = elem->data;
600 end = pos + elem->datalen;
601
602 ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp);
603 if (ret)
604 return ret;
605
606 /* RNR IE may contain more than one NEIGHBOR_AP_INFO */
607 while (pos + sizeof(*ap_info) <= end) {
608 enum nl80211_band band;
609 int freq;
610 u8 length, i, count;
611
612 ap_info = (void *)pos;
613 count = u8_get_bits(ap_info->tbtt_info_hdr,
614 IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
615 length = ap_info->tbtt_info_len;
616
617 pos += sizeof(*ap_info);
618
619 if (!ieee80211_operating_class_to_band(ap_info->op_class,
620 &band))
621 break;
622
623 freq = ieee80211_channel_to_frequency(ap_info->channel, band);
624
625 if (end - pos < count * length)
626 break;
627
628 /*
629 * TBTT info must include bss param + BSSID +
630 * (short SSID or same_ssid bit to be set).
631 * ignore other options, and move to the
632 * next AP info
633 */
634 if (band != NL80211_BAND_6GHZ ||
635 (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&
636 length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {
637 pos += count * length;
638 continue;
639 }
640
641 for (i = 0; i < count; i++) {
642 struct cfg80211_colocated_ap *entry;
643
644 entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
645 GFP_ATOMIC);
646
647 if (!entry)
648 break;
649
650 entry->center_freq = freq;
651
652 if (!cfg80211_parse_ap_info(entry, pos, length,
653 ssid_elem, s_ssid_tmp)) {
654 n_coloc++;
655 list_add_tail(&entry->list, &ap_list);
656 } else {
657 kfree(entry);
658 }
659
660 pos += length;
661 }
662 }
663
664 if (pos != end) {
665 cfg80211_free_coloc_ap_list(&ap_list);
666 return 0;
667 }
668
669 list_splice_tail(&ap_list, list);
670 return n_coloc;
671}
672
673static void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
674 struct ieee80211_channel *chan,
675 bool add_to_6ghz)
676{
677 int i;
678 u32 n_channels = request->n_channels;
679 struct cfg80211_scan_6ghz_params *params =
680 &request->scan_6ghz_params[request->n_6ghz_params];
681
682 for (i = 0; i < n_channels; i++) {
683 if (request->channels[i] == chan) {
684 if (add_to_6ghz)
685 params->channel_idx = i;
686 return;
687 }
688 }
689
690 request->channels[n_channels] = chan;
691 if (add_to_6ghz)
692 request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
693 n_channels;
694
695 request->n_channels++;
696}
697
698static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
699 struct cfg80211_scan_request *request)
700{
701 int i;
702 u32 s_ssid;
703
704 for (i = 0; i < request->n_ssids; i++) {
705 /* wildcard ssid in the scan request */
706 if (!request->ssids[i].ssid_len) {
707 if (ap->multi_bss && !ap->transmitted_bssid)
708 continue;
709
710 return true;
711 }
712
713 if (ap->ssid_len &&
714 ap->ssid_len == request->ssids[i].ssid_len) {
715 if (!memcmp(request->ssids[i].ssid, ap->ssid,
716 ap->ssid_len))
717 return true;
718 } else if (ap->short_ssid_valid) {
719 s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
720 request->ssids[i].ssid_len);
721
722 if (ap->short_ssid == s_ssid)
723 return true;
724 }
725 }
726
727 return false;
728}
729
730static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
731{
732 u8 i;
733 struct cfg80211_colocated_ap *ap;
734 int n_channels, count = 0, err;
735 struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
736 LIST_HEAD(coloc_ap_list);
737 bool need_scan_psc = true;
738 const struct ieee80211_sband_iftype_data *iftd;
739
740 rdev_req->scan_6ghz = true;
741
742 if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
743 return -EOPNOTSUPP;
744
745 iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
746 rdev_req->wdev->iftype);
747 if (!iftd || !iftd->he_cap.has_he)
748 return -EOPNOTSUPP;
749
750 n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
751
752 if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
753 struct cfg80211_internal_bss *intbss;
754
755 spin_lock_bh(&rdev->bss_lock);
756 list_for_each_entry(intbss, &rdev->bss_list, list) {
757 struct cfg80211_bss *res = &intbss->pub;
758 const struct cfg80211_bss_ies *ies;
759
760 ies = rcu_access_pointer(res->ies);
761 count += cfg80211_parse_colocated_ap(ies,
762 &coloc_ap_list);
763 }
764 spin_unlock_bh(&rdev->bss_lock);
765 }
766
767 request = kzalloc(struct_size(request, channels, n_channels) +
768 sizeof(*request->scan_6ghz_params) * count +
769 sizeof(*request->ssids) * rdev_req->n_ssids,
770 GFP_KERNEL);
771 if (!request) {
772 cfg80211_free_coloc_ap_list(&coloc_ap_list);
773 return -ENOMEM;
774 }
775
776 *request = *rdev_req;
777 request->n_channels = 0;
778 request->scan_6ghz_params =
779 (void *)&request->channels[n_channels];
780
781 /*
782 * PSC channels should not be scanned in case of direct scan with 1 SSID
783 * and at least one of the reported co-located APs with same SSID
784 * indicating that all APs in the same ESS are co-located
785 */
786 if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
787 list_for_each_entry(ap, &coloc_ap_list, list) {
788 if (ap->colocated_ess &&
789 cfg80211_find_ssid_match(ap, request)) {
790 need_scan_psc = false;
791 break;
792 }
793 }
794 }
795
796 /*
797 * add to the scan request the channels that need to be scanned
798 * regardless of the collocated APs (PSC channels or all channels
799 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
800 */
801 for (i = 0; i < rdev_req->n_channels; i++) {
802 if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
803 ((need_scan_psc &&
804 cfg80211_channel_is_psc(rdev_req->channels[i])) ||
805 !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
806 cfg80211_scan_req_add_chan(request,
807 rdev_req->channels[i],
808 false);
809 }
810 }
811
812 if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
813 goto skip;
814
815 list_for_each_entry(ap, &coloc_ap_list, list) {
816 bool found = false;
817 struct cfg80211_scan_6ghz_params *scan_6ghz_params =
818 &request->scan_6ghz_params[request->n_6ghz_params];
819 struct ieee80211_channel *chan =
820 ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
821
822 if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
823 continue;
824
825 for (i = 0; i < rdev_req->n_channels; i++) {
826 if (rdev_req->channels[i] == chan)
827 found = true;
828 }
829
830 if (!found)
831 continue;
832
833 if (request->n_ssids > 0 &&
834 !cfg80211_find_ssid_match(ap, request))
835 continue;
836
837 if (!request->n_ssids && ap->multi_bss && !ap->transmitted_bssid)
838 continue;
839
840 cfg80211_scan_req_add_chan(request, chan, true);
841 memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
842 scan_6ghz_params->short_ssid = ap->short_ssid;
843 scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
844 scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
845
846 /*
847 * If a PSC channel is added to the scan and 'need_scan_psc' is
848 * set to false, then all the APs that the scan logic is
849 * interested with on the channel are collocated and thus there
850 * is no need to perform the initial PSC channel listen.
851 */
852 if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
853 scan_6ghz_params->psc_no_listen = true;
854
855 request->n_6ghz_params++;
856 }
857
858skip:
859 cfg80211_free_coloc_ap_list(&coloc_ap_list);
860
861 if (request->n_channels) {
862 struct cfg80211_scan_request *old = rdev->int_scan_req;
863 rdev->int_scan_req = request;
864
865 /*
866 * Add the ssids from the parent scan request to the new scan
867 * request, so the driver would be able to use them in its
868 * probe requests to discover hidden APs on PSC channels.
869 */
870 request->ssids = (void *)&request->channels[request->n_channels];
871 request->n_ssids = rdev_req->n_ssids;
872 memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) *
873 request->n_ssids);
874
875 /*
876 * If this scan follows a previous scan, save the scan start
877 * info from the first part of the scan
878 */
879 if (old)
880 rdev->int_scan_req->info = old->info;
881
882 err = rdev_scan(rdev, request);
883 if (err) {
884 rdev->int_scan_req = old;
885 kfree(request);
886 } else {
887 kfree(old);
888 }
889
890 return err;
891 }
892
893 kfree(request);
894 return -EINVAL;
895}
896
897int cfg80211_scan(struct cfg80211_registered_device *rdev)
898{
899 struct cfg80211_scan_request *request;
900 struct cfg80211_scan_request *rdev_req = rdev->scan_req;
901 u32 n_channels = 0, idx, i;
902
903 if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
904 return rdev_scan(rdev, rdev_req);
905
906 for (i = 0; i < rdev_req->n_channels; i++) {
907 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
908 n_channels++;
909 }
910
911 if (!n_channels)
912 return cfg80211_scan_6ghz(rdev);
913
914 request = kzalloc(struct_size(request, channels, n_channels),
915 GFP_KERNEL);
916 if (!request)
917 return -ENOMEM;
918
919 *request = *rdev_req;
920 request->n_channels = n_channels;
921
922 for (i = idx = 0; i < rdev_req->n_channels; i++) {
923 if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
924 request->channels[idx++] = rdev_req->channels[i];
925 }
926
927 rdev_req->scan_6ghz = false;
928 rdev->int_scan_req = request;
929 return rdev_scan(rdev, request);
930}
931
932void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
933 bool send_message)
934{
935 struct cfg80211_scan_request *request, *rdev_req;
936 struct wireless_dev *wdev;
937 struct sk_buff *msg;
938#ifdef CONFIG_CFG80211_WEXT
939 union iwreq_data wrqu;
940#endif
941
942 lockdep_assert_held(&rdev->wiphy.mtx);
943
944 if (rdev->scan_msg) {
945 nl80211_send_scan_msg(rdev, rdev->scan_msg);
946 rdev->scan_msg = NULL;
947 return;
948 }
949
950 rdev_req = rdev->scan_req;
951 if (!rdev_req)
952 return;
953
954 wdev = rdev_req->wdev;
955 request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
956
957 if (wdev_running(wdev) &&
958 (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
959 !rdev_req->scan_6ghz && !request->info.aborted &&
960 !cfg80211_scan_6ghz(rdev))
961 return;
962
963 /*
964 * This must be before sending the other events!
965 * Otherwise, wpa_supplicant gets completely confused with
966 * wext events.
967 */
968 if (wdev->netdev)
969 cfg80211_sme_scan_done(wdev->netdev);
970
971 if (!request->info.aborted &&
972 request->flags & NL80211_SCAN_FLAG_FLUSH) {
973 /* flush entries from previous scans */
974 spin_lock_bh(&rdev->bss_lock);
975 __cfg80211_bss_expire(rdev, request->scan_start);
976 spin_unlock_bh(&rdev->bss_lock);
977 }
978
979 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
980
981#ifdef CONFIG_CFG80211_WEXT
982 if (wdev->netdev && !request->info.aborted) {
983 memset(&wrqu, 0, sizeof(wrqu));
984
985 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
986 }
987#endif
988
989 dev_put(wdev->netdev);
990
991 kfree(rdev->int_scan_req);
992 rdev->int_scan_req = NULL;
993
994 kfree(rdev->scan_req);
995 rdev->scan_req = NULL;
996
997 if (!send_message)
998 rdev->scan_msg = msg;
999 else
1000 nl80211_send_scan_msg(rdev, msg);
1001}
1002
1003void __cfg80211_scan_done(struct work_struct *wk)
1004{
1005 struct cfg80211_registered_device *rdev;
1006
1007 rdev = container_of(wk, struct cfg80211_registered_device,
1008 scan_done_wk);
1009
1010 wiphy_lock(&rdev->wiphy);
1011 ___cfg80211_scan_done(rdev, true);
1012 wiphy_unlock(&rdev->wiphy);
1013}
1014
1015void cfg80211_scan_done(struct cfg80211_scan_request *request,
1016 struct cfg80211_scan_info *info)
1017{
1018 struct cfg80211_scan_info old_info = request->info;
1019
1020 trace_cfg80211_scan_done(request, info);
1021 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1022 request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1023
1024 request->info = *info;
1025
1026 /*
1027 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1028 * be of the first part. In such a case old_info.scan_start_tsf should
1029 * be non zero.
1030 */
1031 if (request->scan_6ghz && old_info.scan_start_tsf) {
1032 request->info.scan_start_tsf = old_info.scan_start_tsf;
1033 memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1034 sizeof(request->info.tsf_bssid));
1035 }
1036
1037 request->notified = true;
1038 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1039}
1040EXPORT_SYMBOL(cfg80211_scan_done);
1041
1042void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1043 struct cfg80211_sched_scan_request *req)
1044{
1045 lockdep_assert_held(&rdev->wiphy.mtx);
1046
1047 list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1048}
1049
1050static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1051 struct cfg80211_sched_scan_request *req)
1052{
1053 lockdep_assert_held(&rdev->wiphy.mtx);
1054
1055 list_del_rcu(&req->list);
1056 kfree_rcu(req, rcu_head);
1057}
1058
1059static struct cfg80211_sched_scan_request *
1060cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1061{
1062 struct cfg80211_sched_scan_request *pos;
1063
1064 list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1065 lockdep_is_held(&rdev->wiphy.mtx)) {
1066 if (pos->reqid == reqid)
1067 return pos;
1068 }
1069 return NULL;
1070}
1071
1072/*
1073 * Determines if a scheduled scan request can be handled. When a legacy
1074 * scheduled scan is running no other scheduled scan is allowed regardless
1075 * whether the request is for legacy or multi-support scan. When a multi-support
1076 * scheduled scan is running a request for legacy scan is not allowed. In this
1077 * case a request for multi-support scan can be handled if resources are
1078 * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1079 */
1080int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1081 bool want_multi)
1082{
1083 struct cfg80211_sched_scan_request *pos;
1084 int i = 0;
1085
1086 list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1087 /* request id zero means legacy in progress */
1088 if (!i && !pos->reqid)
1089 return -EINPROGRESS;
1090 i++;
1091 }
1092
1093 if (i) {
1094 /* no legacy allowed when multi request(s) are active */
1095 if (!want_multi)
1096 return -EINPROGRESS;
1097
1098 /* resource limit reached */
1099 if (i == rdev->wiphy.max_sched_scan_reqs)
1100 return -ENOSPC;
1101 }
1102 return 0;
1103}
1104
1105void cfg80211_sched_scan_results_wk(struct work_struct *work)
1106{
1107 struct cfg80211_registered_device *rdev;
1108 struct cfg80211_sched_scan_request *req, *tmp;
1109
1110 rdev = container_of(work, struct cfg80211_registered_device,
1111 sched_scan_res_wk);
1112
1113 wiphy_lock(&rdev->wiphy);
1114 list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1115 if (req->report_results) {
1116 req->report_results = false;
1117 if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1118 /* flush entries from previous scans */
1119 spin_lock_bh(&rdev->bss_lock);
1120 __cfg80211_bss_expire(rdev, req->scan_start);
1121 spin_unlock_bh(&rdev->bss_lock);
1122 req->scan_start = jiffies;
1123 }
1124 nl80211_send_sched_scan(req,
1125 NL80211_CMD_SCHED_SCAN_RESULTS);
1126 }
1127 }
1128 wiphy_unlock(&rdev->wiphy);
1129}
1130
1131void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1132{
1133 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1134 struct cfg80211_sched_scan_request *request;
1135
1136 trace_cfg80211_sched_scan_results(wiphy, reqid);
1137 /* ignore if we're not scanning */
1138
1139 rcu_read_lock();
1140 request = cfg80211_find_sched_scan_req(rdev, reqid);
1141 if (request) {
1142 request->report_results = true;
1143 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1144 }
1145 rcu_read_unlock();
1146}
1147EXPORT_SYMBOL(cfg80211_sched_scan_results);
1148
1149void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1150{
1151 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1152
1153 lockdep_assert_held(&wiphy->mtx);
1154
1155 trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1156
1157 __cfg80211_stop_sched_scan(rdev, reqid, true);
1158}
1159EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1160
1161void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1162{
1163 wiphy_lock(wiphy);
1164 cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1165 wiphy_unlock(wiphy);
1166}
1167EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1168
1169int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1170 struct cfg80211_sched_scan_request *req,
1171 bool driver_initiated)
1172{
1173 lockdep_assert_held(&rdev->wiphy.mtx);
1174
1175 if (!driver_initiated) {
1176 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1177 if (err)
1178 return err;
1179 }
1180
1181 nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1182
1183 cfg80211_del_sched_scan_req(rdev, req);
1184
1185 return 0;
1186}
1187
1188int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1189 u64 reqid, bool driver_initiated)
1190{
1191 struct cfg80211_sched_scan_request *sched_scan_req;
1192
1193 lockdep_assert_held(&rdev->wiphy.mtx);
1194
1195 sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1196 if (!sched_scan_req)
1197 return -ENOENT;
1198
1199 return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1200 driver_initiated);
1201}
1202
1203void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1204 unsigned long age_secs)
1205{
1206 struct cfg80211_internal_bss *bss;
1207 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1208
1209 spin_lock_bh(&rdev->bss_lock);
1210 list_for_each_entry(bss, &rdev->bss_list, list)
1211 bss->ts -= age_jiffies;
1212 spin_unlock_bh(&rdev->bss_lock);
1213}
1214
1215void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1216{
1217 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1218}
1219
1220void cfg80211_bss_flush(struct wiphy *wiphy)
1221{
1222 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1223
1224 spin_lock_bh(&rdev->bss_lock);
1225 __cfg80211_bss_expire(rdev, jiffies);
1226 spin_unlock_bh(&rdev->bss_lock);
1227}
1228EXPORT_SYMBOL(cfg80211_bss_flush);
1229
1230const struct element *
1231cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1232 const u8 *match, unsigned int match_len,
1233 unsigned int match_offset)
1234{
1235 const struct element *elem;
1236
1237 for_each_element_id(elem, eid, ies, len) {
1238 if (elem->datalen >= match_offset + match_len &&
1239 !memcmp(elem->data + match_offset, match, match_len))
1240 return elem;
1241 }
1242
1243 return NULL;
1244}
1245EXPORT_SYMBOL(cfg80211_find_elem_match);
1246
1247const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1248 const u8 *ies,
1249 unsigned int len)
1250{
1251 const struct element *elem;
1252 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1253 int match_len = (oui_type < 0) ? 3 : sizeof(match);
1254
1255 if (WARN_ON(oui_type > 0xff))
1256 return NULL;
1257
1258 elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1259 match, match_len, 0);
1260
1261 if (!elem || elem->datalen < 4)
1262 return NULL;
1263
1264 return elem;
1265}
1266EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1267
1268/**
1269 * enum bss_compare_mode - BSS compare mode
1270 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1271 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1272 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1273 */
1274enum bss_compare_mode {
1275 BSS_CMP_REGULAR,
1276 BSS_CMP_HIDE_ZLEN,
1277 BSS_CMP_HIDE_NUL,
1278};
1279
1280static int cmp_bss(struct cfg80211_bss *a,
1281 struct cfg80211_bss *b,
1282 enum bss_compare_mode mode)
1283{
1284 const struct cfg80211_bss_ies *a_ies, *b_ies;
1285 const u8 *ie1 = NULL;
1286 const u8 *ie2 = NULL;
1287 int i, r;
1288
1289 if (a->channel != b->channel)
1290 return (b->channel->center_freq * 1000 + b->channel->freq_offset) -
1291 (a->channel->center_freq * 1000 + a->channel->freq_offset);
1292
1293 a_ies = rcu_access_pointer(a->ies);
1294 if (!a_ies)
1295 return -1;
1296 b_ies = rcu_access_pointer(b->ies);
1297 if (!b_ies)
1298 return 1;
1299
1300 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1301 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1302 a_ies->data, a_ies->len);
1303 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1304 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1305 b_ies->data, b_ies->len);
1306 if (ie1 && ie2) {
1307 int mesh_id_cmp;
1308
1309 if (ie1[1] == ie2[1])
1310 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1311 else
1312 mesh_id_cmp = ie2[1] - ie1[1];
1313
1314 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1315 a_ies->data, a_ies->len);
1316 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1317 b_ies->data, b_ies->len);
1318 if (ie1 && ie2) {
1319 if (mesh_id_cmp)
1320 return mesh_id_cmp;
1321 if (ie1[1] != ie2[1])
1322 return ie2[1] - ie1[1];
1323 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1324 }
1325 }
1326
1327 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1328 if (r)
1329 return r;
1330
1331 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1332 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1333
1334 if (!ie1 && !ie2)
1335 return 0;
1336
1337 /*
1338 * Note that with "hide_ssid", the function returns a match if
1339 * the already-present BSS ("b") is a hidden SSID beacon for
1340 * the new BSS ("a").
1341 */
1342
1343 /* sort missing IE before (left of) present IE */
1344 if (!ie1)
1345 return -1;
1346 if (!ie2)
1347 return 1;
1348
1349 switch (mode) {
1350 case BSS_CMP_HIDE_ZLEN:
1351 /*
1352 * In ZLEN mode we assume the BSS entry we're
1353 * looking for has a zero-length SSID. So if
1354 * the one we're looking at right now has that,
1355 * return 0. Otherwise, return the difference
1356 * in length, but since we're looking for the
1357 * 0-length it's really equivalent to returning
1358 * the length of the one we're looking at.
1359 *
1360 * No content comparison is needed as we assume
1361 * the content length is zero.
1362 */
1363 return ie2[1];
1364 case BSS_CMP_REGULAR:
1365 default:
1366 /* sort by length first, then by contents */
1367 if (ie1[1] != ie2[1])
1368 return ie2[1] - ie1[1];
1369 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1370 case BSS_CMP_HIDE_NUL:
1371 if (ie1[1] != ie2[1])
1372 return ie2[1] - ie1[1];
1373 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1374 for (i = 0; i < ie2[1]; i++)
1375 if (ie2[i + 2])
1376 return -1;
1377 return 0;
1378 }
1379}
1380
1381static bool cfg80211_bss_type_match(u16 capability,
1382 enum nl80211_band band,
1383 enum ieee80211_bss_type bss_type)
1384{
1385 bool ret = true;
1386 u16 mask, val;
1387
1388 if (bss_type == IEEE80211_BSS_TYPE_ANY)
1389 return ret;
1390
1391 if (band == NL80211_BAND_60GHZ) {
1392 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1393 switch (bss_type) {
1394 case IEEE80211_BSS_TYPE_ESS:
1395 val = WLAN_CAPABILITY_DMG_TYPE_AP;
1396 break;
1397 case IEEE80211_BSS_TYPE_PBSS:
1398 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1399 break;
1400 case IEEE80211_BSS_TYPE_IBSS:
1401 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1402 break;
1403 default:
1404 return false;
1405 }
1406 } else {
1407 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1408 switch (bss_type) {
1409 case IEEE80211_BSS_TYPE_ESS:
1410 val = WLAN_CAPABILITY_ESS;
1411 break;
1412 case IEEE80211_BSS_TYPE_IBSS:
1413 val = WLAN_CAPABILITY_IBSS;
1414 break;
1415 case IEEE80211_BSS_TYPE_MBSS:
1416 val = 0;
1417 break;
1418 default:
1419 return false;
1420 }
1421 }
1422
1423 ret = ((capability & mask) == val);
1424 return ret;
1425}
1426
1427/* Returned bss is reference counted and must be cleaned up appropriately. */
1428struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1429 struct ieee80211_channel *channel,
1430 const u8 *bssid,
1431 const u8 *ssid, size_t ssid_len,
1432 enum ieee80211_bss_type bss_type,
1433 enum ieee80211_privacy privacy)
1434{
1435 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1436 struct cfg80211_internal_bss *bss, *res = NULL;
1437 unsigned long now = jiffies;
1438 int bss_privacy;
1439
1440 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1441 privacy);
1442
1443 spin_lock_bh(&rdev->bss_lock);
1444
1445 list_for_each_entry(bss, &rdev->bss_list, list) {
1446 if (!cfg80211_bss_type_match(bss->pub.capability,
1447 bss->pub.channel->band, bss_type))
1448 continue;
1449
1450 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1451 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1452 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1453 continue;
1454 if (channel && bss->pub.channel != channel)
1455 continue;
1456 if (!is_valid_ether_addr(bss->pub.bssid))
1457 continue;
1458 /* Don't get expired BSS structs */
1459 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1460 !atomic_read(&bss->hold))
1461 continue;
1462 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1463 res = bss;
1464 bss_ref_get(rdev, res);
1465 break;
1466 }
1467 }
1468
1469 spin_unlock_bh(&rdev->bss_lock);
1470 if (!res)
1471 return NULL;
1472 trace_cfg80211_return_bss(&res->pub);
1473 return &res->pub;
1474}
1475EXPORT_SYMBOL(cfg80211_get_bss);
1476
1477static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1478 struct cfg80211_internal_bss *bss)
1479{
1480 struct rb_node **p = &rdev->bss_tree.rb_node;
1481 struct rb_node *parent = NULL;
1482 struct cfg80211_internal_bss *tbss;
1483 int cmp;
1484
1485 while (*p) {
1486 parent = *p;
1487 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1488
1489 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1490
1491 if (WARN_ON(!cmp)) {
1492 /* will sort of leak this BSS */
1493 return;
1494 }
1495
1496 if (cmp < 0)
1497 p = &(*p)->rb_left;
1498 else
1499 p = &(*p)->rb_right;
1500 }
1501
1502 rb_link_node(&bss->rbn, parent, p);
1503 rb_insert_color(&bss->rbn, &rdev->bss_tree);
1504}
1505
1506static struct cfg80211_internal_bss *
1507rb_find_bss(struct cfg80211_registered_device *rdev,
1508 struct cfg80211_internal_bss *res,
1509 enum bss_compare_mode mode)
1510{
1511 struct rb_node *n = rdev->bss_tree.rb_node;
1512 struct cfg80211_internal_bss *bss;
1513 int r;
1514
1515 while (n) {
1516 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1517 r = cmp_bss(&res->pub, &bss->pub, mode);
1518
1519 if (r == 0)
1520 return bss;
1521 else if (r < 0)
1522 n = n->rb_left;
1523 else
1524 n = n->rb_right;
1525 }
1526
1527 return NULL;
1528}
1529
1530static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1531 struct cfg80211_internal_bss *new)
1532{
1533 const struct cfg80211_bss_ies *ies;
1534 struct cfg80211_internal_bss *bss;
1535 const u8 *ie;
1536 int i, ssidlen;
1537 u8 fold = 0;
1538 u32 n_entries = 0;
1539
1540 ies = rcu_access_pointer(new->pub.beacon_ies);
1541 if (WARN_ON(!ies))
1542 return false;
1543
1544 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1545 if (!ie) {
1546 /* nothing to do */
1547 return true;
1548 }
1549
1550 ssidlen = ie[1];
1551 for (i = 0; i < ssidlen; i++)
1552 fold |= ie[2 + i];
1553
1554 if (fold) {
1555 /* not a hidden SSID */
1556 return true;
1557 }
1558
1559 /* This is the bad part ... */
1560
1561 list_for_each_entry(bss, &rdev->bss_list, list) {
1562 /*
1563 * we're iterating all the entries anyway, so take the
1564 * opportunity to validate the list length accounting
1565 */
1566 n_entries++;
1567
1568 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1569 continue;
1570 if (bss->pub.channel != new->pub.channel)
1571 continue;
1572 if (bss->pub.scan_width != new->pub.scan_width)
1573 continue;
1574 if (rcu_access_pointer(bss->pub.beacon_ies))
1575 continue;
1576 ies = rcu_access_pointer(bss->pub.ies);
1577 if (!ies)
1578 continue;
1579 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1580 if (!ie)
1581 continue;
1582 if (ssidlen && ie[1] != ssidlen)
1583 continue;
1584 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1585 continue;
1586 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1587 list_del(&bss->hidden_list);
1588 /* combine them */
1589 list_add(&bss->hidden_list, &new->hidden_list);
1590 bss->pub.hidden_beacon_bss = &new->pub;
1591 new->refcount += bss->refcount;
1592 rcu_assign_pointer(bss->pub.beacon_ies,
1593 new->pub.beacon_ies);
1594 }
1595
1596 WARN_ONCE(n_entries != rdev->bss_entries,
1597 "rdev bss entries[%d]/list[len:%d] corruption\n",
1598 rdev->bss_entries, n_entries);
1599
1600 return true;
1601}
1602
1603struct cfg80211_non_tx_bss {
1604 struct cfg80211_bss *tx_bss;
1605 u8 max_bssid_indicator;
1606 u8 bssid_index;
1607};
1608
1609static void cfg80211_update_hidden_bsses(struct cfg80211_internal_bss *known,
1610 const struct cfg80211_bss_ies *new_ies,
1611 const struct cfg80211_bss_ies *old_ies)
1612{
1613 struct cfg80211_internal_bss *bss;
1614
1615 /* Assign beacon IEs to all sub entries */
1616 list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1617 const struct cfg80211_bss_ies *ies;
1618
1619 ies = rcu_access_pointer(bss->pub.beacon_ies);
1620 WARN_ON(ies != old_ies);
1621
1622 rcu_assign_pointer(bss->pub.beacon_ies, new_ies);
1623 }
1624}
1625
1626static bool
1627cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1628 struct cfg80211_internal_bss *known,
1629 struct cfg80211_internal_bss *new,
1630 bool signal_valid)
1631{
1632 lockdep_assert_held(&rdev->bss_lock);
1633
1634 /* Update IEs */
1635 if (rcu_access_pointer(new->pub.proberesp_ies)) {
1636 const struct cfg80211_bss_ies *old;
1637
1638 old = rcu_access_pointer(known->pub.proberesp_ies);
1639
1640 rcu_assign_pointer(known->pub.proberesp_ies,
1641 new->pub.proberesp_ies);
1642 /* Override possible earlier Beacon frame IEs */
1643 rcu_assign_pointer(known->pub.ies,
1644 new->pub.proberesp_ies);
1645 if (old)
1646 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1647 } else if (rcu_access_pointer(new->pub.beacon_ies)) {
1648 const struct cfg80211_bss_ies *old;
1649
1650 if (known->pub.hidden_beacon_bss &&
1651 !list_empty(&known->hidden_list)) {
1652 const struct cfg80211_bss_ies *f;
1653
1654 /* The known BSS struct is one of the probe
1655 * response members of a group, but we're
1656 * receiving a beacon (beacon_ies in the new
1657 * bss is used). This can only mean that the
1658 * AP changed its beacon from not having an
1659 * SSID to showing it, which is confusing so
1660 * drop this information.
1661 */
1662
1663 f = rcu_access_pointer(new->pub.beacon_ies);
1664 kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1665 return false;
1666 }
1667
1668 old = rcu_access_pointer(known->pub.beacon_ies);
1669
1670 rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1671
1672 /* Override IEs if they were from a beacon before */
1673 if (old == rcu_access_pointer(known->pub.ies))
1674 rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1675
1676 cfg80211_update_hidden_bsses(known,
1677 rcu_access_pointer(new->pub.beacon_ies),
1678 old);
1679
1680 if (old)
1681 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1682 }
1683
1684 known->pub.beacon_interval = new->pub.beacon_interval;
1685
1686 /* don't update the signal if beacon was heard on
1687 * adjacent channel.
1688 */
1689 if (signal_valid)
1690 known->pub.signal = new->pub.signal;
1691 known->pub.capability = new->pub.capability;
1692 known->ts = new->ts;
1693 known->ts_boottime = new->ts_boottime;
1694 known->parent_tsf = new->parent_tsf;
1695 known->pub.chains = new->pub.chains;
1696 memcpy(known->pub.chain_signal, new->pub.chain_signal,
1697 IEEE80211_MAX_CHAINS);
1698 ether_addr_copy(known->parent_bssid, new->parent_bssid);
1699 known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1700 known->pub.bssid_index = new->pub.bssid_index;
1701
1702 return true;
1703}
1704
1705/* Returned bss is reference counted and must be cleaned up appropriately. */
1706struct cfg80211_internal_bss *
1707cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1708 struct cfg80211_internal_bss *tmp,
1709 bool signal_valid, unsigned long ts)
1710{
1711 struct cfg80211_internal_bss *found = NULL;
1712
1713 if (WARN_ON(!tmp->pub.channel))
1714 return NULL;
1715
1716 tmp->ts = ts;
1717
1718 spin_lock_bh(&rdev->bss_lock);
1719
1720 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1721 spin_unlock_bh(&rdev->bss_lock);
1722 return NULL;
1723 }
1724
1725 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1726
1727 if (found) {
1728 if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1729 goto drop;
1730 } else {
1731 struct cfg80211_internal_bss *new;
1732 struct cfg80211_internal_bss *hidden;
1733 struct cfg80211_bss_ies *ies;
1734
1735 /*
1736 * create a copy -- the "res" variable that is passed in
1737 * is allocated on the stack since it's not needed in the
1738 * more common case of an update
1739 */
1740 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1741 GFP_ATOMIC);
1742 if (!new) {
1743 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1744 if (ies)
1745 kfree_rcu(ies, rcu_head);
1746 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1747 if (ies)
1748 kfree_rcu(ies, rcu_head);
1749 goto drop;
1750 }
1751 memcpy(new, tmp, sizeof(*new));
1752 new->refcount = 1;
1753 INIT_LIST_HEAD(&new->hidden_list);
1754 INIT_LIST_HEAD(&new->pub.nontrans_list);
1755 /* we'll set this later if it was non-NULL */
1756 new->pub.transmitted_bss = NULL;
1757
1758 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1759 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1760 if (!hidden)
1761 hidden = rb_find_bss(rdev, tmp,
1762 BSS_CMP_HIDE_NUL);
1763 if (hidden) {
1764 new->pub.hidden_beacon_bss = &hidden->pub;
1765 list_add(&new->hidden_list,
1766 &hidden->hidden_list);
1767 hidden->refcount++;
1768 rcu_assign_pointer(new->pub.beacon_ies,
1769 hidden->pub.beacon_ies);
1770 }
1771 } else {
1772 /*
1773 * Ok so we found a beacon, and don't have an entry. If
1774 * it's a beacon with hidden SSID, we might be in for an
1775 * expensive search for any probe responses that should
1776 * be grouped with this beacon for updates ...
1777 */
1778 if (!cfg80211_combine_bsses(rdev, new)) {
1779 bss_ref_put(rdev, new);
1780 goto drop;
1781 }
1782 }
1783
1784 if (rdev->bss_entries >= bss_entries_limit &&
1785 !cfg80211_bss_expire_oldest(rdev)) {
1786 bss_ref_put(rdev, new);
1787 goto drop;
1788 }
1789
1790 /* This must be before the call to bss_ref_get */
1791 if (tmp->pub.transmitted_bss) {
1792 new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1793 bss_ref_get(rdev, bss_from_pub(tmp->pub.transmitted_bss));
1794 }
1795
1796 list_add_tail(&new->list, &rdev->bss_list);
1797 rdev->bss_entries++;
1798 rb_insert_bss(rdev, new);
1799 found = new;
1800 }
1801
1802 rdev->bss_generation++;
1803 bss_ref_get(rdev, found);
1804 spin_unlock_bh(&rdev->bss_lock);
1805
1806 return found;
1807 drop:
1808 spin_unlock_bh(&rdev->bss_lock);
1809 return NULL;
1810}
1811
1812int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen,
1813 enum nl80211_band band,
1814 enum cfg80211_bss_frame_type ftype)
1815{
1816 const struct element *tmp;
1817
1818 if (band == NL80211_BAND_6GHZ) {
1819 struct ieee80211_he_operation *he_oper;
1820
1821 tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie,
1822 ielen);
1823 if (tmp && tmp->datalen >= sizeof(*he_oper) &&
1824 tmp->datalen >= ieee80211_he_oper_size(&tmp->data[1])) {
1825 const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
1826
1827 he_oper = (void *)&tmp->data[1];
1828
1829 he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
1830 if (!he_6ghz_oper)
1831 return -1;
1832
1833 if (ftype != CFG80211_BSS_FTYPE_BEACON ||
1834 he_6ghz_oper->control & IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)
1835 return he_6ghz_oper->primary;
1836 }
1837 } else if (band == NL80211_BAND_S1GHZ) {
1838 tmp = cfg80211_find_elem(WLAN_EID_S1G_OPERATION, ie, ielen);
1839 if (tmp && tmp->datalen >= sizeof(struct ieee80211_s1g_oper_ie)) {
1840 struct ieee80211_s1g_oper_ie *s1gop = (void *)tmp->data;
1841
1842 return s1gop->oper_ch;
1843 }
1844 } else {
1845 tmp = cfg80211_find_elem(WLAN_EID_DS_PARAMS, ie, ielen);
1846 if (tmp && tmp->datalen == 1)
1847 return tmp->data[0];
1848
1849 tmp = cfg80211_find_elem(WLAN_EID_HT_OPERATION, ie, ielen);
1850 if (tmp &&
1851 tmp->datalen >= sizeof(struct ieee80211_ht_operation)) {
1852 struct ieee80211_ht_operation *htop = (void *)tmp->data;
1853
1854 return htop->primary_chan;
1855 }
1856 }
1857
1858 return -1;
1859}
1860EXPORT_SYMBOL(cfg80211_get_ies_channel_number);
1861
1862/*
1863 * Update RX channel information based on the available frame payload
1864 * information. This is mainly for the 2.4 GHz band where frames can be received
1865 * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1866 * element to indicate the current (transmitting) channel, but this might also
1867 * be needed on other bands if RX frequency does not match with the actual
1868 * operating channel of a BSS, or if the AP reports a different primary channel.
1869 */
1870static struct ieee80211_channel *
1871cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1872 struct ieee80211_channel *channel,
1873 enum nl80211_bss_scan_width scan_width,
1874 enum cfg80211_bss_frame_type ftype)
1875{
1876 u32 freq;
1877 int channel_number;
1878 struct ieee80211_channel *alt_channel;
1879
1880 channel_number = cfg80211_get_ies_channel_number(ie, ielen,
1881 channel->band, ftype);
1882
1883 if (channel_number < 0) {
1884 /* No channel information in frame payload */
1885 return channel;
1886 }
1887
1888 freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1889
1890 /*
1891 * In 6GHz, duplicated beacon indication is relevant for
1892 * beacons only.
1893 */
1894 if (channel->band == NL80211_BAND_6GHZ &&
1895 (freq == channel->center_freq ||
1896 abs(freq - channel->center_freq) > 80))
1897 return channel;
1898
1899 alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1900 if (!alt_channel) {
1901 if (channel->band == NL80211_BAND_2GHZ) {
1902 /*
1903 * Better not allow unexpected channels when that could
1904 * be going beyond the 1-11 range (e.g., discovering
1905 * BSS on channel 12 when radio is configured for
1906 * channel 11.
1907 */
1908 return NULL;
1909 }
1910
1911 /* No match for the payload channel number - ignore it */
1912 return channel;
1913 }
1914
1915 if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1916 scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1917 /*
1918 * Ignore channel number in 5 and 10 MHz channels where there
1919 * may not be an n:1 or 1:n mapping between frequencies and
1920 * channel numbers.
1921 */
1922 return channel;
1923 }
1924
1925 /*
1926 * Use the channel determined through the payload channel number
1927 * instead of the RX channel reported by the driver.
1928 */
1929 if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1930 return NULL;
1931 return alt_channel;
1932}
1933
1934/* Returned bss is reference counted and must be cleaned up appropriately. */
1935static struct cfg80211_bss *
1936cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1937 struct cfg80211_inform_bss *data,
1938 enum cfg80211_bss_frame_type ftype,
1939 const u8 *bssid, u64 tsf, u16 capability,
1940 u16 beacon_interval, const u8 *ie, size_t ielen,
1941 struct cfg80211_non_tx_bss *non_tx_data,
1942 gfp_t gfp)
1943{
1944 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1945 struct cfg80211_bss_ies *ies;
1946 struct ieee80211_channel *channel;
1947 struct cfg80211_internal_bss tmp = {}, *res;
1948 int bss_type;
1949 bool signal_valid;
1950 unsigned long ts;
1951
1952 if (WARN_ON(!wiphy))
1953 return NULL;
1954
1955 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1956 (data->signal < 0 || data->signal > 100)))
1957 return NULL;
1958
1959 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1960 data->scan_width, ftype);
1961 if (!channel)
1962 return NULL;
1963
1964 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1965 tmp.pub.channel = channel;
1966 tmp.pub.scan_width = data->scan_width;
1967 tmp.pub.signal = data->signal;
1968 tmp.pub.beacon_interval = beacon_interval;
1969 tmp.pub.capability = capability;
1970 tmp.ts_boottime = data->boottime_ns;
1971 tmp.parent_tsf = data->parent_tsf;
1972 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1973
1974 if (non_tx_data) {
1975 tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1976 ts = bss_from_pub(non_tx_data->tx_bss)->ts;
1977 tmp.pub.bssid_index = non_tx_data->bssid_index;
1978 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1979 } else {
1980 ts = jiffies;
1981 }
1982
1983 /*
1984 * If we do not know here whether the IEs are from a Beacon or Probe
1985 * Response frame, we need to pick one of the options and only use it
1986 * with the driver that does not provide the full Beacon/Probe Response
1987 * frame. Use Beacon frame pointer to avoid indicating that this should
1988 * override the IEs pointer should we have received an earlier
1989 * indication of Probe Response data.
1990 */
1991 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1992 if (!ies)
1993 return NULL;
1994 ies->len = ielen;
1995 ies->tsf = tsf;
1996 ies->from_beacon = false;
1997 memcpy(ies->data, ie, ielen);
1998
1999 switch (ftype) {
2000 case CFG80211_BSS_FTYPE_BEACON:
2001 ies->from_beacon = true;
2002 fallthrough;
2003 case CFG80211_BSS_FTYPE_UNKNOWN:
2004 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2005 break;
2006 case CFG80211_BSS_FTYPE_PRESP:
2007 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2008 break;
2009 }
2010 rcu_assign_pointer(tmp.pub.ies, ies);
2011
2012 signal_valid = data->chan == channel;
2013 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
2014 if (!res)
2015 return NULL;
2016
2017 if (channel->band == NL80211_BAND_60GHZ) {
2018 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2019 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2020 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2021 regulatory_hint_found_beacon(wiphy, channel, gfp);
2022 } else {
2023 if (res->pub.capability & WLAN_CAPABILITY_ESS)
2024 regulatory_hint_found_beacon(wiphy, channel, gfp);
2025 }
2026
2027 if (non_tx_data) {
2028 /* this is a nontransmitting bss, we need to add it to
2029 * transmitting bss' list if it is not there
2030 */
2031 spin_lock_bh(&rdev->bss_lock);
2032 if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
2033 &res->pub)) {
2034 if (__cfg80211_unlink_bss(rdev, res)) {
2035 rdev->bss_generation++;
2036 res = NULL;
2037 }
2038 }
2039 spin_unlock_bh(&rdev->bss_lock);
2040
2041 if (!res)
2042 return NULL;
2043 }
2044
2045 trace_cfg80211_return_bss(&res->pub);
2046 /* cfg80211_bss_update gives us a referenced result */
2047 return &res->pub;
2048}
2049
2050static const struct element
2051*cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
2052 const struct element *mbssid_elem,
2053 const struct element *sub_elem)
2054{
2055 const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
2056 const struct element *next_mbssid;
2057 const struct element *next_sub;
2058
2059 next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2060 mbssid_end,
2061 ielen - (mbssid_end - ie));
2062
2063 /*
2064 * If it is not the last subelement in current MBSSID IE or there isn't
2065 * a next MBSSID IE - profile is complete.
2066 */
2067 if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2068 !next_mbssid)
2069 return NULL;
2070
2071 /* For any length error, just return NULL */
2072
2073 if (next_mbssid->datalen < 4)
2074 return NULL;
2075
2076 next_sub = (void *)&next_mbssid->data[1];
2077
2078 if (next_mbssid->data + next_mbssid->datalen <
2079 next_sub->data + next_sub->datalen)
2080 return NULL;
2081
2082 if (next_sub->id != 0 || next_sub->datalen < 2)
2083 return NULL;
2084
2085 /*
2086 * Check if the first element in the next sub element is a start
2087 * of a new profile
2088 */
2089 return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2090 NULL : next_mbssid;
2091}
2092
2093size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2094 const struct element *mbssid_elem,
2095 const struct element *sub_elem,
2096 u8 *merged_ie, size_t max_copy_len)
2097{
2098 size_t copied_len = sub_elem->datalen;
2099 const struct element *next_mbssid;
2100
2101 if (sub_elem->datalen > max_copy_len)
2102 return 0;
2103
2104 memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2105
2106 while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2107 mbssid_elem,
2108 sub_elem))) {
2109 const struct element *next_sub = (void *)&next_mbssid->data[1];
2110
2111 if (copied_len + next_sub->datalen > max_copy_len)
2112 break;
2113 memcpy(merged_ie + copied_len, next_sub->data,
2114 next_sub->datalen);
2115 copied_len += next_sub->datalen;
2116 }
2117
2118 return copied_len;
2119}
2120EXPORT_SYMBOL(cfg80211_merge_profile);
2121
2122static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2123 struct cfg80211_inform_bss *data,
2124 enum cfg80211_bss_frame_type ftype,
2125 const u8 *bssid, u64 tsf,
2126 u16 beacon_interval, const u8 *ie,
2127 size_t ielen,
2128 struct cfg80211_non_tx_bss *non_tx_data,
2129 gfp_t gfp)
2130{
2131 const u8 *mbssid_index_ie;
2132 const struct element *elem, *sub;
2133 size_t new_ie_len;
2134 u8 new_bssid[ETH_ALEN];
2135 u8 *new_ie, *profile;
2136 u64 seen_indices = 0;
2137 u16 capability;
2138 struct cfg80211_bss *bss;
2139
2140 if (!non_tx_data)
2141 return;
2142 if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2143 return;
2144 if (!wiphy->support_mbssid)
2145 return;
2146 if (wiphy->support_only_he_mbssid &&
2147 !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2148 return;
2149
2150 new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2151 if (!new_ie)
2152 return;
2153
2154 profile = kmalloc(ielen, gfp);
2155 if (!profile)
2156 goto out;
2157
2158 for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
2159 if (elem->datalen < 4)
2160 continue;
2161 if (elem->data[0] < 1 || (int)elem->data[0] > 8)
2162 continue;
2163 for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2164 u8 profile_len;
2165
2166 if (sub->id != 0 || sub->datalen < 4) {
2167 /* not a valid BSS profile */
2168 continue;
2169 }
2170
2171 if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2172 sub->data[1] != 2) {
2173 /* The first element within the Nontransmitted
2174 * BSSID Profile is not the Nontransmitted
2175 * BSSID Capability element.
2176 */
2177 continue;
2178 }
2179
2180 memset(profile, 0, ielen);
2181 profile_len = cfg80211_merge_profile(ie, ielen,
2182 elem,
2183 sub,
2184 profile,
2185 ielen);
2186
2187 /* found a Nontransmitted BSSID Profile */
2188 mbssid_index_ie = cfg80211_find_ie
2189 (WLAN_EID_MULTI_BSSID_IDX,
2190 profile, profile_len);
2191 if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2192 mbssid_index_ie[2] == 0 ||
2193 mbssid_index_ie[2] > 46) {
2194 /* No valid Multiple BSSID-Index element */
2195 continue;
2196 }
2197
2198 if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2199 /* We don't support legacy split of a profile */
2200 net_dbg_ratelimited("Partial info for BSSID index %d\n",
2201 mbssid_index_ie[2]);
2202
2203 seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2204
2205 non_tx_data->bssid_index = mbssid_index_ie[2];
2206 non_tx_data->max_bssid_indicator = elem->data[0];
2207
2208 cfg80211_gen_new_bssid(bssid,
2209 non_tx_data->max_bssid_indicator,
2210 non_tx_data->bssid_index,
2211 new_bssid);
2212 memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2213 new_ie_len = cfg80211_gen_new_ie(ie, ielen,
2214 profile,
2215 profile_len, new_ie,
2216 gfp);
2217 if (!new_ie_len)
2218 continue;
2219
2220 capability = get_unaligned_le16(profile + 2);
2221 bss = cfg80211_inform_single_bss_data(wiphy, data,
2222 ftype,
2223 new_bssid, tsf,
2224 capability,
2225 beacon_interval,
2226 new_ie,
2227 new_ie_len,
2228 non_tx_data,
2229 gfp);
2230 if (!bss)
2231 break;
2232 cfg80211_put_bss(wiphy, bss);
2233 }
2234 }
2235
2236out:
2237 kfree(new_ie);
2238 kfree(profile);
2239}
2240
2241struct cfg80211_bss *
2242cfg80211_inform_bss_data(struct wiphy *wiphy,
2243 struct cfg80211_inform_bss *data,
2244 enum cfg80211_bss_frame_type ftype,
2245 const u8 *bssid, u64 tsf, u16 capability,
2246 u16 beacon_interval, const u8 *ie, size_t ielen,
2247 gfp_t gfp)
2248{
2249 struct cfg80211_bss *res;
2250 struct cfg80211_non_tx_bss non_tx_data;
2251
2252 res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
2253 capability, beacon_interval, ie,
2254 ielen, NULL, gfp);
2255 if (!res)
2256 return NULL;
2257 non_tx_data.tx_bss = res;
2258 cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
2259 beacon_interval, ie, ielen, &non_tx_data,
2260 gfp);
2261 return res;
2262}
2263EXPORT_SYMBOL(cfg80211_inform_bss_data);
2264
2265static void
2266cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
2267 struct cfg80211_inform_bss *data,
2268 struct ieee80211_mgmt *mgmt, size_t len,
2269 struct cfg80211_non_tx_bss *non_tx_data,
2270 gfp_t gfp)
2271{
2272 enum cfg80211_bss_frame_type ftype;
2273 const u8 *ie = mgmt->u.probe_resp.variable;
2274 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2275 u.probe_resp.variable);
2276
2277 ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2278 CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2279
2280 cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
2281 le64_to_cpu(mgmt->u.probe_resp.timestamp),
2282 le16_to_cpu(mgmt->u.probe_resp.beacon_int),
2283 ie, ielen, non_tx_data, gfp);
2284}
2285
2286static void
2287cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
2288 struct cfg80211_bss *nontrans_bss,
2289 struct ieee80211_mgmt *mgmt, size_t len)
2290{
2291 u8 *ie, *new_ie, *pos;
2292 const struct element *nontrans_ssid;
2293 const u8 *trans_ssid, *mbssid;
2294 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2295 u.probe_resp.variable);
2296 size_t new_ie_len;
2297 struct cfg80211_bss_ies *new_ies;
2298 const struct cfg80211_bss_ies *old;
2299 size_t cpy_len;
2300
2301 lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
2302
2303 ie = mgmt->u.probe_resp.variable;
2304
2305 new_ie_len = ielen;
2306 trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
2307 if (!trans_ssid)
2308 return;
2309 new_ie_len -= trans_ssid[1];
2310 mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
2311 /*
2312 * It's not valid to have the MBSSID element before SSID
2313 * ignore if that happens - the code below assumes it is
2314 * after (while copying things inbetween).
2315 */
2316 if (!mbssid || mbssid < trans_ssid)
2317 return;
2318 new_ie_len -= mbssid[1];
2319
2320 nontrans_ssid = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
2321 if (!nontrans_ssid)
2322 return;
2323
2324 new_ie_len += nontrans_ssid->datalen;
2325
2326 /* generate new ie for nontrans BSS
2327 * 1. replace SSID with nontrans BSS' SSID
2328 * 2. skip MBSSID IE
2329 */
2330 new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
2331 if (!new_ie)
2332 return;
2333
2334 new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
2335 if (!new_ies)
2336 goto out_free;
2337
2338 pos = new_ie;
2339
2340 /* copy the nontransmitted SSID */
2341 cpy_len = nontrans_ssid->datalen + 2;
2342 memcpy(pos, nontrans_ssid, cpy_len);
2343 pos += cpy_len;
2344 /* copy the IEs between SSID and MBSSID */
2345 cpy_len = trans_ssid[1] + 2;
2346 memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
2347 pos += (mbssid - (trans_ssid + cpy_len));
2348 /* copy the IEs after MBSSID */
2349 cpy_len = mbssid[1] + 2;
2350 memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
2351
2352 /* update ie */
2353 new_ies->len = new_ie_len;
2354 new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2355 new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
2356 memcpy(new_ies->data, new_ie, new_ie_len);
2357 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
2358 old = rcu_access_pointer(nontrans_bss->proberesp_ies);
2359 rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
2360 rcu_assign_pointer(nontrans_bss->ies, new_ies);
2361 if (old)
2362 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2363 } else {
2364 old = rcu_access_pointer(nontrans_bss->beacon_ies);
2365 rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
2366 cfg80211_update_hidden_bsses(bss_from_pub(nontrans_bss),
2367 new_ies, old);
2368 rcu_assign_pointer(nontrans_bss->ies, new_ies);
2369 if (old)
2370 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2371 }
2372
2373out_free:
2374 kfree(new_ie);
2375}
2376
2377/* cfg80211_inform_bss_width_frame helper */
2378static struct cfg80211_bss *
2379cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2380 struct cfg80211_inform_bss *data,
2381 struct ieee80211_mgmt *mgmt, size_t len,
2382 gfp_t gfp)
2383{
2384 struct cfg80211_internal_bss tmp = {}, *res;
2385 struct cfg80211_bss_ies *ies;
2386 struct ieee80211_channel *channel;
2387 bool signal_valid;
2388 struct ieee80211_ext *ext = NULL;
2389 u8 *bssid, *variable;
2390 u16 capability, beacon_int;
2391 size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2392 u.probe_resp.variable);
2393 int bss_type;
2394 enum cfg80211_bss_frame_type ftype;
2395
2396 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2397 offsetof(struct ieee80211_mgmt, u.beacon.variable));
2398
2399 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2400
2401 if (WARN_ON(!mgmt))
2402 return NULL;
2403
2404 if (WARN_ON(!wiphy))
2405 return NULL;
2406
2407 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2408 (data->signal < 0 || data->signal > 100)))
2409 return NULL;
2410
2411 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2412 ext = (void *) mgmt;
2413 min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2414 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2415 min_hdr_len = offsetof(struct ieee80211_ext,
2416 u.s1g_short_beacon.variable);
2417 }
2418
2419 if (WARN_ON(len < min_hdr_len))
2420 return NULL;
2421
2422 ielen = len - min_hdr_len;
2423 variable = mgmt->u.probe_resp.variable;
2424 if (ext) {
2425 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2426 variable = ext->u.s1g_short_beacon.variable;
2427 else
2428 variable = ext->u.s1g_beacon.variable;
2429 }
2430
2431 if (ieee80211_is_beacon(mgmt->frame_control))
2432 ftype = CFG80211_BSS_FTYPE_BEACON;
2433 else if (ieee80211_is_probe_resp(mgmt->frame_control))
2434 ftype = CFG80211_BSS_FTYPE_PRESP;
2435 else
2436 ftype = CFG80211_BSS_FTYPE_UNKNOWN;
2437
2438 channel = cfg80211_get_bss_channel(wiphy, variable,
2439 ielen, data->chan, data->scan_width,
2440 ftype);
2441 if (!channel)
2442 return NULL;
2443
2444 if (ext) {
2445 const struct ieee80211_s1g_bcn_compat_ie *compat;
2446 const struct element *elem;
2447
2448 elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2449 variable, ielen);
2450 if (!elem)
2451 return NULL;
2452 if (elem->datalen < sizeof(*compat))
2453 return NULL;
2454 compat = (void *)elem->data;
2455 bssid = ext->u.s1g_beacon.sa;
2456 capability = le16_to_cpu(compat->compat_info);
2457 beacon_int = le16_to_cpu(compat->beacon_int);
2458 } else {
2459 bssid = mgmt->bssid;
2460 beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2461 capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2462 }
2463
2464 ies = kzalloc(sizeof(*ies) + ielen, gfp);
2465 if (!ies)
2466 return NULL;
2467 ies->len = ielen;
2468 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2469 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2470 ieee80211_is_s1g_beacon(mgmt->frame_control);
2471 memcpy(ies->data, variable, ielen);
2472
2473 if (ieee80211_is_probe_resp(mgmt->frame_control))
2474 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2475 else
2476 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2477 rcu_assign_pointer(tmp.pub.ies, ies);
2478
2479 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2480 tmp.pub.beacon_interval = beacon_int;
2481 tmp.pub.capability = capability;
2482 tmp.pub.channel = channel;
2483 tmp.pub.scan_width = data->scan_width;
2484 tmp.pub.signal = data->signal;
2485 tmp.ts_boottime = data->boottime_ns;
2486 tmp.parent_tsf = data->parent_tsf;
2487 tmp.pub.chains = data->chains;
2488 memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2489 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2490
2491 signal_valid = data->chan == channel;
2492 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
2493 jiffies);
2494 if (!res)
2495 return NULL;
2496
2497 if (channel->band == NL80211_BAND_60GHZ) {
2498 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2499 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2500 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2501 regulatory_hint_found_beacon(wiphy, channel, gfp);
2502 } else {
2503 if (res->pub.capability & WLAN_CAPABILITY_ESS)
2504 regulatory_hint_found_beacon(wiphy, channel, gfp);
2505 }
2506
2507 trace_cfg80211_return_bss(&res->pub);
2508 /* cfg80211_bss_update gives us a referenced result */
2509 return &res->pub;
2510}
2511
2512struct cfg80211_bss *
2513cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2514 struct cfg80211_inform_bss *data,
2515 struct ieee80211_mgmt *mgmt, size_t len,
2516 gfp_t gfp)
2517{
2518 struct cfg80211_bss *res, *tmp_bss;
2519 const u8 *ie = mgmt->u.probe_resp.variable;
2520 const struct cfg80211_bss_ies *ies1, *ies2;
2521 size_t ielen = len - offsetof(struct ieee80211_mgmt,
2522 u.probe_resp.variable);
2523 struct cfg80211_non_tx_bss non_tx_data = {};
2524
2525 res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2526 len, gfp);
2527
2528 /* don't do any further MBSSID handling for S1G */
2529 if (ieee80211_is_s1g_beacon(mgmt->frame_control))
2530 return res;
2531
2532 if (!res || !wiphy->support_mbssid ||
2533 !cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2534 return res;
2535 if (wiphy->support_only_he_mbssid &&
2536 !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2537 return res;
2538
2539 non_tx_data.tx_bss = res;
2540 /* process each non-transmitting bss */
2541 cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
2542 &non_tx_data, gfp);
2543
2544 spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2545
2546 /* check if the res has other nontransmitting bss which is not
2547 * in MBSSID IE
2548 */
2549 ies1 = rcu_access_pointer(res->ies);
2550
2551 /* go through nontrans_list, if the timestamp of the BSS is
2552 * earlier than the timestamp of the transmitting BSS then
2553 * update it
2554 */
2555 list_for_each_entry(tmp_bss, &res->nontrans_list,
2556 nontrans_list) {
2557 ies2 = rcu_access_pointer(tmp_bss->ies);
2558 if (ies2->tsf < ies1->tsf)
2559 cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
2560 mgmt, len);
2561 }
2562 spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2563
2564 return res;
2565}
2566EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2567
2568void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2569{
2570 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2571
2572 if (!pub)
2573 return;
2574
2575 spin_lock_bh(&rdev->bss_lock);
2576 bss_ref_get(rdev, bss_from_pub(pub));
2577 spin_unlock_bh(&rdev->bss_lock);
2578}
2579EXPORT_SYMBOL(cfg80211_ref_bss);
2580
2581void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2582{
2583 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2584
2585 if (!pub)
2586 return;
2587
2588 spin_lock_bh(&rdev->bss_lock);
2589 bss_ref_put(rdev, bss_from_pub(pub));
2590 spin_unlock_bh(&rdev->bss_lock);
2591}
2592EXPORT_SYMBOL(cfg80211_put_bss);
2593
2594void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2595{
2596 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2597 struct cfg80211_internal_bss *bss, *tmp1;
2598 struct cfg80211_bss *nontrans_bss, *tmp;
2599
2600 if (WARN_ON(!pub))
2601 return;
2602
2603 bss = bss_from_pub(pub);
2604
2605 spin_lock_bh(&rdev->bss_lock);
2606 if (list_empty(&bss->list))
2607 goto out;
2608
2609 list_for_each_entry_safe(nontrans_bss, tmp,
2610 &pub->nontrans_list,
2611 nontrans_list) {
2612 tmp1 = bss_from_pub(nontrans_bss);
2613 if (__cfg80211_unlink_bss(rdev, tmp1))
2614 rdev->bss_generation++;
2615 }
2616
2617 if (__cfg80211_unlink_bss(rdev, bss))
2618 rdev->bss_generation++;
2619out:
2620 spin_unlock_bh(&rdev->bss_lock);
2621}
2622EXPORT_SYMBOL(cfg80211_unlink_bss);
2623
2624void cfg80211_bss_iter(struct wiphy *wiphy,
2625 struct cfg80211_chan_def *chandef,
2626 void (*iter)(struct wiphy *wiphy,
2627 struct cfg80211_bss *bss,
2628 void *data),
2629 void *iter_data)
2630{
2631 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2632 struct cfg80211_internal_bss *bss;
2633
2634 spin_lock_bh(&rdev->bss_lock);
2635
2636 list_for_each_entry(bss, &rdev->bss_list, list) {
2637 if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel,
2638 false))
2639 iter(wiphy, &bss->pub, iter_data);
2640 }
2641
2642 spin_unlock_bh(&rdev->bss_lock);
2643}
2644EXPORT_SYMBOL(cfg80211_bss_iter);
2645
2646void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
2647 unsigned int link_id,
2648 struct ieee80211_channel *chan)
2649{
2650 struct wiphy *wiphy = wdev->wiphy;
2651 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2652 struct cfg80211_internal_bss *cbss = wdev->links[link_id].client.current_bss;
2653 struct cfg80211_internal_bss *new = NULL;
2654 struct cfg80211_internal_bss *bss;
2655 struct cfg80211_bss *nontrans_bss;
2656 struct cfg80211_bss *tmp;
2657
2658 spin_lock_bh(&rdev->bss_lock);
2659
2660 /*
2661 * Some APs use CSA also for bandwidth changes, i.e., without actually
2662 * changing the control channel, so no need to update in such a case.
2663 */
2664 if (cbss->pub.channel == chan)
2665 goto done;
2666
2667 /* use transmitting bss */
2668 if (cbss->pub.transmitted_bss)
2669 cbss = bss_from_pub(cbss->pub.transmitted_bss);
2670
2671 cbss->pub.channel = chan;
2672
2673 list_for_each_entry(bss, &rdev->bss_list, list) {
2674 if (!cfg80211_bss_type_match(bss->pub.capability,
2675 bss->pub.channel->band,
2676 wdev->conn_bss_type))
2677 continue;
2678
2679 if (bss == cbss)
2680 continue;
2681
2682 if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
2683 new = bss;
2684 break;
2685 }
2686 }
2687
2688 if (new) {
2689 /* to save time, update IEs for transmitting bss only */
2690 if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
2691 new->pub.proberesp_ies = NULL;
2692 new->pub.beacon_ies = NULL;
2693 }
2694
2695 list_for_each_entry_safe(nontrans_bss, tmp,
2696 &new->pub.nontrans_list,
2697 nontrans_list) {
2698 bss = bss_from_pub(nontrans_bss);
2699 if (__cfg80211_unlink_bss(rdev, bss))
2700 rdev->bss_generation++;
2701 }
2702
2703 WARN_ON(atomic_read(&new->hold));
2704 if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
2705 rdev->bss_generation++;
2706 }
2707
2708 rb_erase(&cbss->rbn, &rdev->bss_tree);
2709 rb_insert_bss(rdev, cbss);
2710 rdev->bss_generation++;
2711
2712 list_for_each_entry_safe(nontrans_bss, tmp,
2713 &cbss->pub.nontrans_list,
2714 nontrans_list) {
2715 bss = bss_from_pub(nontrans_bss);
2716 bss->pub.channel = chan;
2717 rb_erase(&bss->rbn, &rdev->bss_tree);
2718 rb_insert_bss(rdev, bss);
2719 rdev->bss_generation++;
2720 }
2721
2722done:
2723 spin_unlock_bh(&rdev->bss_lock);
2724}
2725
2726#ifdef CONFIG_CFG80211_WEXT
2727static struct cfg80211_registered_device *
2728cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
2729{
2730 struct cfg80211_registered_device *rdev;
2731 struct net_device *dev;
2732
2733 ASSERT_RTNL();
2734
2735 dev = dev_get_by_index(net, ifindex);
2736 if (!dev)
2737 return ERR_PTR(-ENODEV);
2738 if (dev->ieee80211_ptr)
2739 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
2740 else
2741 rdev = ERR_PTR(-ENODEV);
2742 dev_put(dev);
2743 return rdev;
2744}
2745
2746int cfg80211_wext_siwscan(struct net_device *dev,
2747 struct iw_request_info *info,
2748 union iwreq_data *wrqu, char *extra)
2749{
2750 struct cfg80211_registered_device *rdev;
2751 struct wiphy *wiphy;
2752 struct iw_scan_req *wreq = NULL;
2753 struct cfg80211_scan_request *creq;
2754 int i, err, n_channels = 0;
2755 enum nl80211_band band;
2756
2757 if (!netif_running(dev))
2758 return -ENETDOWN;
2759
2760 if (wrqu->data.length == sizeof(struct iw_scan_req))
2761 wreq = (struct iw_scan_req *)extra;
2762
2763 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2764
2765 if (IS_ERR(rdev))
2766 return PTR_ERR(rdev);
2767
2768 if (rdev->scan_req || rdev->scan_msg)
2769 return -EBUSY;
2770
2771 wiphy = &rdev->wiphy;
2772
2773 /* Determine number of channels, needed to allocate creq */
2774 if (wreq && wreq->num_channels)
2775 n_channels = wreq->num_channels;
2776 else
2777 n_channels = ieee80211_get_num_supported_channels(wiphy);
2778
2779 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2780 n_channels * sizeof(void *),
2781 GFP_ATOMIC);
2782 if (!creq)
2783 return -ENOMEM;
2784
2785 creq->wiphy = wiphy;
2786 creq->wdev = dev->ieee80211_ptr;
2787 /* SSIDs come after channels */
2788 creq->ssids = (void *)&creq->channels[n_channels];
2789 creq->n_channels = n_channels;
2790 creq->n_ssids = 1;
2791 creq->scan_start = jiffies;
2792
2793 /* translate "Scan on frequencies" request */
2794 i = 0;
2795 for (band = 0; band < NUM_NL80211_BANDS; band++) {
2796 int j;
2797
2798 if (!wiphy->bands[band])
2799 continue;
2800
2801 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2802 /* ignore disabled channels */
2803 if (wiphy->bands[band]->channels[j].flags &
2804 IEEE80211_CHAN_DISABLED)
2805 continue;
2806
2807 /* If we have a wireless request structure and the
2808 * wireless request specifies frequencies, then search
2809 * for the matching hardware channel.
2810 */
2811 if (wreq && wreq->num_channels) {
2812 int k;
2813 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2814 for (k = 0; k < wreq->num_channels; k++) {
2815 struct iw_freq *freq =
2816 &wreq->channel_list[k];
2817 int wext_freq =
2818 cfg80211_wext_freq(freq);
2819
2820 if (wext_freq == wiphy_freq)
2821 goto wext_freq_found;
2822 }
2823 goto wext_freq_not_found;
2824 }
2825
2826 wext_freq_found:
2827 creq->channels[i] = &wiphy->bands[band]->channels[j];
2828 i++;
2829 wext_freq_not_found: ;
2830 }
2831 }
2832 /* No channels found? */
2833 if (!i) {
2834 err = -EINVAL;
2835 goto out;
2836 }
2837
2838 /* Set real number of channels specified in creq->channels[] */
2839 creq->n_channels = i;
2840
2841 /* translate "Scan for SSID" request */
2842 if (wreq) {
2843 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2844 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2845 err = -EINVAL;
2846 goto out;
2847 }
2848 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2849 creq->ssids[0].ssid_len = wreq->essid_len;
2850 }
2851 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2852 creq->n_ssids = 0;
2853 }
2854
2855 for (i = 0; i < NUM_NL80211_BANDS; i++)
2856 if (wiphy->bands[i])
2857 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2858
2859 eth_broadcast_addr(creq->bssid);
2860
2861 wiphy_lock(&rdev->wiphy);
2862
2863 rdev->scan_req = creq;
2864 err = rdev_scan(rdev, creq);
2865 if (err) {
2866 rdev->scan_req = NULL;
2867 /* creq will be freed below */
2868 } else {
2869 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2870 /* creq now owned by driver */
2871 creq = NULL;
2872 dev_hold(dev);
2873 }
2874 wiphy_unlock(&rdev->wiphy);
2875 out:
2876 kfree(creq);
2877 return err;
2878}
2879EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2880
2881static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2882 const struct cfg80211_bss_ies *ies,
2883 char *current_ev, char *end_buf)
2884{
2885 const u8 *pos, *end, *next;
2886 struct iw_event iwe;
2887
2888 if (!ies)
2889 return current_ev;
2890
2891 /*
2892 * If needed, fragment the IEs buffer (at IE boundaries) into short
2893 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2894 */
2895 pos = ies->data;
2896 end = pos + ies->len;
2897
2898 while (end - pos > IW_GENERIC_IE_MAX) {
2899 next = pos + 2 + pos[1];
2900 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2901 next = next + 2 + next[1];
2902
2903 memset(&iwe, 0, sizeof(iwe));
2904 iwe.cmd = IWEVGENIE;
2905 iwe.u.data.length = next - pos;
2906 current_ev = iwe_stream_add_point_check(info, current_ev,
2907 end_buf, &iwe,
2908 (void *)pos);
2909 if (IS_ERR(current_ev))
2910 return current_ev;
2911 pos = next;
2912 }
2913
2914 if (end > pos) {
2915 memset(&iwe, 0, sizeof(iwe));
2916 iwe.cmd = IWEVGENIE;
2917 iwe.u.data.length = end - pos;
2918 current_ev = iwe_stream_add_point_check(info, current_ev,
2919 end_buf, &iwe,
2920 (void *)pos);
2921 if (IS_ERR(current_ev))
2922 return current_ev;
2923 }
2924
2925 return current_ev;
2926}
2927
2928static char *
2929ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2930 struct cfg80211_internal_bss *bss, char *current_ev,
2931 char *end_buf)
2932{
2933 const struct cfg80211_bss_ies *ies;
2934 struct iw_event iwe;
2935 const u8 *ie;
2936 u8 buf[50];
2937 u8 *cfg, *p, *tmp;
2938 int rem, i, sig;
2939 bool ismesh = false;
2940
2941 memset(&iwe, 0, sizeof(iwe));
2942 iwe.cmd = SIOCGIWAP;
2943 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2944 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2945 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2946 IW_EV_ADDR_LEN);
2947 if (IS_ERR(current_ev))
2948 return current_ev;
2949
2950 memset(&iwe, 0, sizeof(iwe));
2951 iwe.cmd = SIOCGIWFREQ;
2952 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2953 iwe.u.freq.e = 0;
2954 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2955 IW_EV_FREQ_LEN);
2956 if (IS_ERR(current_ev))
2957 return current_ev;
2958
2959 memset(&iwe, 0, sizeof(iwe));
2960 iwe.cmd = SIOCGIWFREQ;
2961 iwe.u.freq.m = bss->pub.channel->center_freq;
2962 iwe.u.freq.e = 6;
2963 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2964 IW_EV_FREQ_LEN);
2965 if (IS_ERR(current_ev))
2966 return current_ev;
2967
2968 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2969 memset(&iwe, 0, sizeof(iwe));
2970 iwe.cmd = IWEVQUAL;
2971 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2972 IW_QUAL_NOISE_INVALID |
2973 IW_QUAL_QUAL_UPDATED;
2974 switch (wiphy->signal_type) {
2975 case CFG80211_SIGNAL_TYPE_MBM:
2976 sig = bss->pub.signal / 100;
2977 iwe.u.qual.level = sig;
2978 iwe.u.qual.updated |= IW_QUAL_DBM;
2979 if (sig < -110) /* rather bad */
2980 sig = -110;
2981 else if (sig > -40) /* perfect */
2982 sig = -40;
2983 /* will give a range of 0 .. 70 */
2984 iwe.u.qual.qual = sig + 110;
2985 break;
2986 case CFG80211_SIGNAL_TYPE_UNSPEC:
2987 iwe.u.qual.level = bss->pub.signal;
2988 /* will give range 0 .. 100 */
2989 iwe.u.qual.qual = bss->pub.signal;
2990 break;
2991 default:
2992 /* not reached */
2993 break;
2994 }
2995 current_ev = iwe_stream_add_event_check(info, current_ev,
2996 end_buf, &iwe,
2997 IW_EV_QUAL_LEN);
2998 if (IS_ERR(current_ev))
2999 return current_ev;
3000 }
3001
3002 memset(&iwe, 0, sizeof(iwe));
3003 iwe.cmd = SIOCGIWENCODE;
3004 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
3005 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
3006 else
3007 iwe.u.data.flags = IW_ENCODE_DISABLED;
3008 iwe.u.data.length = 0;
3009 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3010 &iwe, "");
3011 if (IS_ERR(current_ev))
3012 return current_ev;
3013
3014 rcu_read_lock();
3015 ies = rcu_dereference(bss->pub.ies);
3016 rem = ies->len;
3017 ie = ies->data;
3018
3019 while (rem >= 2) {
3020 /* invalid data */
3021 if (ie[1] > rem - 2)
3022 break;
3023
3024 switch (ie[0]) {
3025 case WLAN_EID_SSID:
3026 memset(&iwe, 0, sizeof(iwe));
3027 iwe.cmd = SIOCGIWESSID;
3028 iwe.u.data.length = ie[1];
3029 iwe.u.data.flags = 1;
3030 current_ev = iwe_stream_add_point_check(info,
3031 current_ev,
3032 end_buf, &iwe,
3033 (u8 *)ie + 2);
3034 if (IS_ERR(current_ev))
3035 goto unlock;
3036 break;
3037 case WLAN_EID_MESH_ID:
3038 memset(&iwe, 0, sizeof(iwe));
3039 iwe.cmd = SIOCGIWESSID;
3040 iwe.u.data.length = ie[1];
3041 iwe.u.data.flags = 1;
3042 current_ev = iwe_stream_add_point_check(info,
3043 current_ev,
3044 end_buf, &iwe,
3045 (u8 *)ie + 2);
3046 if (IS_ERR(current_ev))
3047 goto unlock;
3048 break;
3049 case WLAN_EID_MESH_CONFIG:
3050 ismesh = true;
3051 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
3052 break;
3053 cfg = (u8 *)ie + 2;
3054 memset(&iwe, 0, sizeof(iwe));
3055 iwe.cmd = IWEVCUSTOM;
3056 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
3057 "0x%02X", cfg[0]);
3058 iwe.u.data.length = strlen(buf);
3059 current_ev = iwe_stream_add_point_check(info,
3060 current_ev,
3061 end_buf,
3062 &iwe, buf);
3063 if (IS_ERR(current_ev))
3064 goto unlock;
3065 sprintf(buf, "Path Selection Metric ID: 0x%02X",
3066 cfg[1]);
3067 iwe.u.data.length = strlen(buf);
3068 current_ev = iwe_stream_add_point_check(info,
3069 current_ev,
3070 end_buf,
3071 &iwe, buf);
3072 if (IS_ERR(current_ev))
3073 goto unlock;
3074 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3075 cfg[2]);
3076 iwe.u.data.length = strlen(buf);
3077 current_ev = iwe_stream_add_point_check(info,
3078 current_ev,
3079 end_buf,
3080 &iwe, buf);
3081 if (IS_ERR(current_ev))
3082 goto unlock;
3083 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3084 iwe.u.data.length = strlen(buf);
3085 current_ev = iwe_stream_add_point_check(info,
3086 current_ev,
3087 end_buf,
3088 &iwe, buf);
3089 if (IS_ERR(current_ev))
3090 goto unlock;
3091 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3092 iwe.u.data.length = strlen(buf);
3093 current_ev = iwe_stream_add_point_check(info,
3094 current_ev,
3095 end_buf,
3096 &iwe, buf);
3097 if (IS_ERR(current_ev))
3098 goto unlock;
3099 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3100 iwe.u.data.length = strlen(buf);
3101 current_ev = iwe_stream_add_point_check(info,
3102 current_ev,
3103 end_buf,
3104 &iwe, buf);
3105 if (IS_ERR(current_ev))
3106 goto unlock;
3107 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3108 iwe.u.data.length = strlen(buf);
3109 current_ev = iwe_stream_add_point_check(info,
3110 current_ev,
3111 end_buf,
3112 &iwe, buf);
3113 if (IS_ERR(current_ev))
3114 goto unlock;
3115 break;
3116 case WLAN_EID_SUPP_RATES:
3117 case WLAN_EID_EXT_SUPP_RATES:
3118 /* display all supported rates in readable format */
3119 p = current_ev + iwe_stream_lcp_len(info);
3120
3121 memset(&iwe, 0, sizeof(iwe));
3122 iwe.cmd = SIOCGIWRATE;
3123 /* Those two flags are ignored... */
3124 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3125
3126 for (i = 0; i < ie[1]; i++) {
3127 iwe.u.bitrate.value =
3128 ((ie[i + 2] & 0x7f) * 500000);
3129 tmp = p;
3130 p = iwe_stream_add_value(info, current_ev, p,
3131 end_buf, &iwe,
3132 IW_EV_PARAM_LEN);
3133 if (p == tmp) {
3134 current_ev = ERR_PTR(-E2BIG);
3135 goto unlock;
3136 }
3137 }
3138 current_ev = p;
3139 break;
3140 }
3141 rem -= ie[1] + 2;
3142 ie += ie[1] + 2;
3143 }
3144
3145 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3146 ismesh) {
3147 memset(&iwe, 0, sizeof(iwe));
3148 iwe.cmd = SIOCGIWMODE;
3149 if (ismesh)
3150 iwe.u.mode = IW_MODE_MESH;
3151 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3152 iwe.u.mode = IW_MODE_MASTER;
3153 else
3154 iwe.u.mode = IW_MODE_ADHOC;
3155 current_ev = iwe_stream_add_event_check(info, current_ev,
3156 end_buf, &iwe,
3157 IW_EV_UINT_LEN);
3158 if (IS_ERR(current_ev))
3159 goto unlock;
3160 }
3161
3162 memset(&iwe, 0, sizeof(iwe));
3163 iwe.cmd = IWEVCUSTOM;
3164 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3165 iwe.u.data.length = strlen(buf);
3166 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3167 &iwe, buf);
3168 if (IS_ERR(current_ev))
3169 goto unlock;
3170 memset(&iwe, 0, sizeof(iwe));
3171 iwe.cmd = IWEVCUSTOM;
3172 sprintf(buf, " Last beacon: %ums ago",
3173 elapsed_jiffies_msecs(bss->ts));
3174 iwe.u.data.length = strlen(buf);
3175 current_ev = iwe_stream_add_point_check(info, current_ev,
3176 end_buf, &iwe, buf);
3177 if (IS_ERR(current_ev))
3178 goto unlock;
3179
3180 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3181
3182 unlock:
3183 rcu_read_unlock();
3184 return current_ev;
3185}
3186
3187
3188static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3189 struct iw_request_info *info,
3190 char *buf, size_t len)
3191{
3192 char *current_ev = buf;
3193 char *end_buf = buf + len;
3194 struct cfg80211_internal_bss *bss;
3195 int err = 0;
3196
3197 spin_lock_bh(&rdev->bss_lock);
3198 cfg80211_bss_expire(rdev);
3199
3200 list_for_each_entry(bss, &rdev->bss_list, list) {
3201 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3202 err = -E2BIG;
3203 break;
3204 }
3205 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3206 current_ev, end_buf);
3207 if (IS_ERR(current_ev)) {
3208 err = PTR_ERR(current_ev);
3209 break;
3210 }
3211 }
3212 spin_unlock_bh(&rdev->bss_lock);
3213
3214 if (err)
3215 return err;
3216 return current_ev - buf;
3217}
3218
3219
3220int cfg80211_wext_giwscan(struct net_device *dev,
3221 struct iw_request_info *info,
3222 union iwreq_data *wrqu, char *extra)
3223{
3224 struct iw_point *data = &wrqu->data;
3225 struct cfg80211_registered_device *rdev;
3226 int res;
3227
3228 if (!netif_running(dev))
3229 return -ENETDOWN;
3230
3231 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3232
3233 if (IS_ERR(rdev))
3234 return PTR_ERR(rdev);
3235
3236 if (rdev->scan_req || rdev->scan_msg)
3237 return -EAGAIN;
3238
3239 res = ieee80211_scan_results(rdev, info, extra, data->length);
3240 data->length = 0;
3241 if (res >= 0) {
3242 data->length = res;
3243 res = 0;
3244 }
3245
3246 return res;
3247}
3248EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3249#endif