Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-microblaze.git] / net / wireless / scan.c
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) 2018-2019 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 <net/arp.h>
18 #include <net/cfg80211.h>
19 #include <net/cfg80211-wext.h>
20 #include <net/iw_handler.h>
21 #include "core.h"
22 #include "nl80211.h"
23 #include "wext-compat.h"
24 #include "rdev-ops.h"
25
26 /**
27  * DOC: BSS tree/list structure
28  *
29  * At the top level, the BSS list is kept in both a list in each
30  * registered device (@bss_list) as well as an RB-tree for faster
31  * lookup. In the RB-tree, entries can be looked up using their
32  * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
33  * for other BSSes.
34  *
35  * Due to the possibility of hidden SSIDs, there's a second level
36  * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
37  * The hidden_list connects all BSSes belonging to a single AP
38  * that has a hidden SSID, and connects beacon and probe response
39  * entries. For a probe response entry for a hidden SSID, the
40  * hidden_beacon_bss pointer points to the BSS struct holding the
41  * beacon's information.
42  *
43  * Reference counting is done for all these references except for
44  * the hidden_list, so that a beacon BSS struct that is otherwise
45  * not referenced has one reference for being on the bss_list and
46  * one for each probe response entry that points to it using the
47  * hidden_beacon_bss pointer. When a BSS struct that has such a
48  * pointer is get/put, the refcount update is also propagated to
49  * the referenced struct, this ensure that it cannot get removed
50  * while somebody is using the probe response version.
51  *
52  * Note that the hidden_beacon_bss pointer never changes, due to
53  * the reference counting. Therefore, no locking is needed for
54  * it.
55  *
56  * Also note that the hidden_beacon_bss pointer is only relevant
57  * if the driver uses something other than the IEs, e.g. private
58  * data stored stored in the BSS struct, since the beacon IEs are
59  * also linked into the probe response struct.
60  */
61
62 /*
63  * Limit the number of BSS entries stored in mac80211. Each one is
64  * a bit over 4k at most, so this limits to roughly 4-5M of memory.
65  * If somebody wants to really attack this though, they'd likely
66  * use small beacons, and only one type of frame, limiting each of
67  * the entries to a much smaller size (in order to generate more
68  * entries in total, so overhead is bigger.)
69  */
70 static int bss_entries_limit = 1000;
71 module_param(bss_entries_limit, int, 0644);
72 MODULE_PARM_DESC(bss_entries_limit,
73                  "limit to number of scan BSS entries (per wiphy, default 1000)");
74
75 #define IEEE80211_SCAN_RESULT_EXPIRE    (30 * HZ)
76
77 static void bss_free(struct cfg80211_internal_bss *bss)
78 {
79         struct cfg80211_bss_ies *ies;
80
81         if (WARN_ON(atomic_read(&bss->hold)))
82                 return;
83
84         ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
85         if (ies && !bss->pub.hidden_beacon_bss)
86                 kfree_rcu(ies, rcu_head);
87         ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
88         if (ies)
89                 kfree_rcu(ies, rcu_head);
90
91         /*
92          * This happens when the module is removed, it doesn't
93          * really matter any more save for completeness
94          */
95         if (!list_empty(&bss->hidden_list))
96                 list_del(&bss->hidden_list);
97
98         kfree(bss);
99 }
100
101 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
102                                struct cfg80211_internal_bss *bss)
103 {
104         lockdep_assert_held(&rdev->bss_lock);
105
106         bss->refcount++;
107         if (bss->pub.hidden_beacon_bss) {
108                 bss = container_of(bss->pub.hidden_beacon_bss,
109                                    struct cfg80211_internal_bss,
110                                    pub);
111                 bss->refcount++;
112         }
113         if (bss->pub.transmitted_bss) {
114                 bss = container_of(bss->pub.transmitted_bss,
115                                    struct cfg80211_internal_bss,
116                                    pub);
117                 bss->refcount++;
118         }
119 }
120
121 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
122                                struct cfg80211_internal_bss *bss)
123 {
124         lockdep_assert_held(&rdev->bss_lock);
125
126         if (bss->pub.hidden_beacon_bss) {
127                 struct cfg80211_internal_bss *hbss;
128                 hbss = container_of(bss->pub.hidden_beacon_bss,
129                                     struct cfg80211_internal_bss,
130                                     pub);
131                 hbss->refcount--;
132                 if (hbss->refcount == 0)
133                         bss_free(hbss);
134         }
135
136         if (bss->pub.transmitted_bss) {
137                 struct cfg80211_internal_bss *tbss;
138
139                 tbss = container_of(bss->pub.transmitted_bss,
140                                     struct cfg80211_internal_bss,
141                                     pub);
142                 tbss->refcount--;
143                 if (tbss->refcount == 0)
144                         bss_free(tbss);
145         }
146
147         bss->refcount--;
148         if (bss->refcount == 0)
149                 bss_free(bss);
150 }
151
152 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
153                                   struct cfg80211_internal_bss *bss)
154 {
155         lockdep_assert_held(&rdev->bss_lock);
156
157         if (!list_empty(&bss->hidden_list)) {
158                 /*
159                  * don't remove the beacon entry if it has
160                  * probe responses associated with it
161                  */
162                 if (!bss->pub.hidden_beacon_bss)
163                         return false;
164                 /*
165                  * if it's a probe response entry break its
166                  * link to the other entries in the group
167                  */
168                 list_del_init(&bss->hidden_list);
169         }
170
171         list_del_init(&bss->list);
172         list_del_init(&bss->pub.nontrans_list);
173         rb_erase(&bss->rbn, &rdev->bss_tree);
174         rdev->bss_entries--;
175         WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
176                   "rdev bss entries[%d]/list[empty:%d] corruption\n",
177                   rdev->bss_entries, list_empty(&rdev->bss_list));
178         bss_ref_put(rdev, bss);
179         return true;
180 }
181
182 bool cfg80211_is_element_inherited(const struct element *elem,
183                                    const struct element *non_inherit_elem)
184 {
185         u8 id_len, ext_id_len, i, loop_len, id;
186         const u8 *list;
187
188         if (elem->id == WLAN_EID_MULTIPLE_BSSID)
189                 return false;
190
191         if (!non_inherit_elem || non_inherit_elem->datalen < 2)
192                 return true;
193
194         /*
195          * non inheritance element format is:
196          * ext ID (56) | IDs list len | list | extension IDs list len | list
197          * Both lists are optional. Both lengths are mandatory.
198          * This means valid length is:
199          * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
200          */
201         id_len = non_inherit_elem->data[1];
202         if (non_inherit_elem->datalen < 3 + id_len)
203                 return true;
204
205         ext_id_len = non_inherit_elem->data[2 + id_len];
206         if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
207                 return true;
208
209         if (elem->id == WLAN_EID_EXTENSION) {
210                 if (!ext_id_len)
211                         return true;
212                 loop_len = ext_id_len;
213                 list = &non_inherit_elem->data[3 + id_len];
214                 id = elem->data[0];
215         } else {
216                 if (!id_len)
217                         return true;
218                 loop_len = id_len;
219                 list = &non_inherit_elem->data[2];
220                 id = elem->id;
221         }
222
223         for (i = 0; i < loop_len; i++) {
224                 if (list[i] == id)
225                         return false;
226         }
227
228         return true;
229 }
230 EXPORT_SYMBOL(cfg80211_is_element_inherited);
231
232 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
233                                   const u8 *subelement, size_t subie_len,
234                                   u8 *new_ie, gfp_t gfp)
235 {
236         u8 *pos, *tmp;
237         const u8 *tmp_old, *tmp_new;
238         const struct element *non_inherit_elem;
239         u8 *sub_copy;
240
241         /* copy subelement as we need to change its content to
242          * mark an ie after it is processed.
243          */
244         sub_copy = kmemdup(subelement, subie_len, gfp);
245         if (!sub_copy)
246                 return 0;
247
248         pos = &new_ie[0];
249
250         /* set new ssid */
251         tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
252         if (tmp_new) {
253                 memcpy(pos, tmp_new, tmp_new[1] + 2);
254                 pos += (tmp_new[1] + 2);
255         }
256
257         /* get non inheritance list if exists */
258         non_inherit_elem =
259                 cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
260                                        sub_copy, subie_len);
261
262         /* go through IEs in ie (skip SSID) and subelement,
263          * merge them into new_ie
264          */
265         tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
266         tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
267
268         while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {
269                 if (tmp_old[0] == 0) {
270                         tmp_old++;
271                         continue;
272                 }
273
274                 if (tmp_old[0] == WLAN_EID_EXTENSION)
275                         tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
276                                                          subie_len);
277                 else
278                         tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
279                                                      subie_len);
280
281                 if (!tmp) {
282                         const struct element *old_elem = (void *)tmp_old;
283
284                         /* ie in old ie but not in subelement */
285                         if (cfg80211_is_element_inherited(old_elem,
286                                                           non_inherit_elem)) {
287                                 memcpy(pos, tmp_old, tmp_old[1] + 2);
288                                 pos += tmp_old[1] + 2;
289                         }
290                 } else {
291                         /* ie in transmitting ie also in subelement,
292                          * copy from subelement and flag the ie in subelement
293                          * as copied (by setting eid field to WLAN_EID_SSID,
294                          * which is skipped anyway).
295                          * For vendor ie, compare OUI + type + subType to
296                          * determine if they are the same ie.
297                          */
298                         if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
299                                 if (!memcmp(tmp_old + 2, tmp + 2, 5)) {
300                                         /* same vendor ie, copy from
301                                          * subelement
302                                          */
303                                         memcpy(pos, tmp, tmp[1] + 2);
304                                         pos += tmp[1] + 2;
305                                         tmp[0] = WLAN_EID_SSID;
306                                 } else {
307                                         memcpy(pos, tmp_old, tmp_old[1] + 2);
308                                         pos += tmp_old[1] + 2;
309                                 }
310                         } else {
311                                 /* copy ie from subelement into new ie */
312                                 memcpy(pos, tmp, tmp[1] + 2);
313                                 pos += tmp[1] + 2;
314                                 tmp[0] = WLAN_EID_SSID;
315                         }
316                 }
317
318                 if (tmp_old + tmp_old[1] + 2 - ie == ielen)
319                         break;
320
321                 tmp_old += tmp_old[1] + 2;
322         }
323
324         /* go through subelement again to check if there is any ie not
325          * copied to new ie, skip ssid, capability, bssid-index ie
326          */
327         tmp_new = sub_copy;
328         while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
329                 if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
330                       tmp_new[0] == WLAN_EID_SSID)) {
331                         memcpy(pos, tmp_new, tmp_new[1] + 2);
332                         pos += tmp_new[1] + 2;
333                 }
334                 if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
335                         break;
336                 tmp_new += tmp_new[1] + 2;
337         }
338
339         kfree(sub_copy);
340         return pos - new_ie;
341 }
342
343 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
344                    const u8 *ssid, size_t ssid_len)
345 {
346         const struct cfg80211_bss_ies *ies;
347         const u8 *ssidie;
348
349         if (bssid && !ether_addr_equal(a->bssid, bssid))
350                 return false;
351
352         if (!ssid)
353                 return true;
354
355         ies = rcu_access_pointer(a->ies);
356         if (!ies)
357                 return false;
358         ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
359         if (!ssidie)
360                 return false;
361         if (ssidie[1] != ssid_len)
362                 return false;
363         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
364 }
365
366 static int
367 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
368                            struct cfg80211_bss *nontrans_bss)
369 {
370         const u8 *ssid;
371         size_t ssid_len;
372         struct cfg80211_bss *bss = NULL;
373
374         rcu_read_lock();
375         ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
376         if (!ssid) {
377                 rcu_read_unlock();
378                 return -EINVAL;
379         }
380         ssid_len = ssid[1];
381         ssid = ssid + 2;
382         rcu_read_unlock();
383
384         /* check if nontrans_bss is in the list */
385         list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
386                 if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
387                         return 0;
388         }
389
390         /* add to the list */
391         list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
392         return 0;
393 }
394
395 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
396                                   unsigned long expire_time)
397 {
398         struct cfg80211_internal_bss *bss, *tmp;
399         bool expired = false;
400
401         lockdep_assert_held(&rdev->bss_lock);
402
403         list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
404                 if (atomic_read(&bss->hold))
405                         continue;
406                 if (!time_after(expire_time, bss->ts))
407                         continue;
408
409                 if (__cfg80211_unlink_bss(rdev, bss))
410                         expired = true;
411         }
412
413         if (expired)
414                 rdev->bss_generation++;
415 }
416
417 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
418 {
419         struct cfg80211_internal_bss *bss, *oldest = NULL;
420         bool ret;
421
422         lockdep_assert_held(&rdev->bss_lock);
423
424         list_for_each_entry(bss, &rdev->bss_list, list) {
425                 if (atomic_read(&bss->hold))
426                         continue;
427
428                 if (!list_empty(&bss->hidden_list) &&
429                     !bss->pub.hidden_beacon_bss)
430                         continue;
431
432                 if (oldest && time_before(oldest->ts, bss->ts))
433                         continue;
434                 oldest = bss;
435         }
436
437         if (WARN_ON(!oldest))
438                 return false;
439
440         /*
441          * The callers make sure to increase rdev->bss_generation if anything
442          * gets removed (and a new entry added), so there's no need to also do
443          * it here.
444          */
445
446         ret = __cfg80211_unlink_bss(rdev, oldest);
447         WARN_ON(!ret);
448         return ret;
449 }
450
451 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
452                            bool send_message)
453 {
454         struct cfg80211_scan_request *request;
455         struct wireless_dev *wdev;
456         struct sk_buff *msg;
457 #ifdef CONFIG_CFG80211_WEXT
458         union iwreq_data wrqu;
459 #endif
460
461         ASSERT_RTNL();
462
463         if (rdev->scan_msg) {
464                 nl80211_send_scan_msg(rdev, rdev->scan_msg);
465                 rdev->scan_msg = NULL;
466                 return;
467         }
468
469         request = rdev->scan_req;
470         if (!request)
471                 return;
472
473         wdev = request->wdev;
474
475         /*
476          * This must be before sending the other events!
477          * Otherwise, wpa_supplicant gets completely confused with
478          * wext events.
479          */
480         if (wdev->netdev)
481                 cfg80211_sme_scan_done(wdev->netdev);
482
483         if (!request->info.aborted &&
484             request->flags & NL80211_SCAN_FLAG_FLUSH) {
485                 /* flush entries from previous scans */
486                 spin_lock_bh(&rdev->bss_lock);
487                 __cfg80211_bss_expire(rdev, request->scan_start);
488                 spin_unlock_bh(&rdev->bss_lock);
489         }
490
491         msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
492
493 #ifdef CONFIG_CFG80211_WEXT
494         if (wdev->netdev && !request->info.aborted) {
495                 memset(&wrqu, 0, sizeof(wrqu));
496
497                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
498         }
499 #endif
500
501         if (wdev->netdev)
502                 dev_put(wdev->netdev);
503
504         rdev->scan_req = NULL;
505         kfree(request);
506
507         if (!send_message)
508                 rdev->scan_msg = msg;
509         else
510                 nl80211_send_scan_msg(rdev, msg);
511 }
512
513 void __cfg80211_scan_done(struct work_struct *wk)
514 {
515         struct cfg80211_registered_device *rdev;
516
517         rdev = container_of(wk, struct cfg80211_registered_device,
518                             scan_done_wk);
519
520         rtnl_lock();
521         ___cfg80211_scan_done(rdev, true);
522         rtnl_unlock();
523 }
524
525 void cfg80211_scan_done(struct cfg80211_scan_request *request,
526                         struct cfg80211_scan_info *info)
527 {
528         trace_cfg80211_scan_done(request, info);
529         WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
530
531         request->info = *info;
532         request->notified = true;
533         queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
534 }
535 EXPORT_SYMBOL(cfg80211_scan_done);
536
537 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
538                                  struct cfg80211_sched_scan_request *req)
539 {
540         ASSERT_RTNL();
541
542         list_add_rcu(&req->list, &rdev->sched_scan_req_list);
543 }
544
545 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
546                                         struct cfg80211_sched_scan_request *req)
547 {
548         ASSERT_RTNL();
549
550         list_del_rcu(&req->list);
551         kfree_rcu(req, rcu_head);
552 }
553
554 static struct cfg80211_sched_scan_request *
555 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
556 {
557         struct cfg80211_sched_scan_request *pos;
558
559         WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
560
561         list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list) {
562                 if (pos->reqid == reqid)
563                         return pos;
564         }
565         return NULL;
566 }
567
568 /*
569  * Determines if a scheduled scan request can be handled. When a legacy
570  * scheduled scan is running no other scheduled scan is allowed regardless
571  * whether the request is for legacy or multi-support scan. When a multi-support
572  * scheduled scan is running a request for legacy scan is not allowed. In this
573  * case a request for multi-support scan can be handled if resources are
574  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
575  */
576 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
577                                      bool want_multi)
578 {
579         struct cfg80211_sched_scan_request *pos;
580         int i = 0;
581
582         list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
583                 /* request id zero means legacy in progress */
584                 if (!i && !pos->reqid)
585                         return -EINPROGRESS;
586                 i++;
587         }
588
589         if (i) {
590                 /* no legacy allowed when multi request(s) are active */
591                 if (!want_multi)
592                         return -EINPROGRESS;
593
594                 /* resource limit reached */
595                 if (i == rdev->wiphy.max_sched_scan_reqs)
596                         return -ENOSPC;
597         }
598         return 0;
599 }
600
601 void cfg80211_sched_scan_results_wk(struct work_struct *work)
602 {
603         struct cfg80211_registered_device *rdev;
604         struct cfg80211_sched_scan_request *req, *tmp;
605
606         rdev = container_of(work, struct cfg80211_registered_device,
607                            sched_scan_res_wk);
608
609         rtnl_lock();
610         list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
611                 if (req->report_results) {
612                         req->report_results = false;
613                         if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
614                                 /* flush entries from previous scans */
615                                 spin_lock_bh(&rdev->bss_lock);
616                                 __cfg80211_bss_expire(rdev, req->scan_start);
617                                 spin_unlock_bh(&rdev->bss_lock);
618                                 req->scan_start = jiffies;
619                         }
620                         nl80211_send_sched_scan(req,
621                                                 NL80211_CMD_SCHED_SCAN_RESULTS);
622                 }
623         }
624         rtnl_unlock();
625 }
626
627 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
628 {
629         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
630         struct cfg80211_sched_scan_request *request;
631
632         trace_cfg80211_sched_scan_results(wiphy, reqid);
633         /* ignore if we're not scanning */
634
635         rcu_read_lock();
636         request = cfg80211_find_sched_scan_req(rdev, reqid);
637         if (request) {
638                 request->report_results = true;
639                 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
640         }
641         rcu_read_unlock();
642 }
643 EXPORT_SYMBOL(cfg80211_sched_scan_results);
644
645 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy, u64 reqid)
646 {
647         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
648
649         ASSERT_RTNL();
650
651         trace_cfg80211_sched_scan_stopped(wiphy, reqid);
652
653         __cfg80211_stop_sched_scan(rdev, reqid, true);
654 }
655 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
656
657 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
658 {
659         rtnl_lock();
660         cfg80211_sched_scan_stopped_rtnl(wiphy, reqid);
661         rtnl_unlock();
662 }
663 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
664
665 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
666                                  struct cfg80211_sched_scan_request *req,
667                                  bool driver_initiated)
668 {
669         ASSERT_RTNL();
670
671         if (!driver_initiated) {
672                 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
673                 if (err)
674                         return err;
675         }
676
677         nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
678
679         cfg80211_del_sched_scan_req(rdev, req);
680
681         return 0;
682 }
683
684 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
685                                u64 reqid, bool driver_initiated)
686 {
687         struct cfg80211_sched_scan_request *sched_scan_req;
688
689         ASSERT_RTNL();
690
691         sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
692         if (!sched_scan_req)
693                 return -ENOENT;
694
695         return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
696                                             driver_initiated);
697 }
698
699 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
700                       unsigned long age_secs)
701 {
702         struct cfg80211_internal_bss *bss;
703         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
704
705         spin_lock_bh(&rdev->bss_lock);
706         list_for_each_entry(bss, &rdev->bss_list, list)
707                 bss->ts -= age_jiffies;
708         spin_unlock_bh(&rdev->bss_lock);
709 }
710
711 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
712 {
713         __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
714 }
715
716 const struct element *
717 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
718                          const u8 *match, unsigned int match_len,
719                          unsigned int match_offset)
720 {
721         const struct element *elem;
722
723         for_each_element_id(elem, eid, ies, len) {
724                 if (elem->datalen >= match_offset + match_len &&
725                     !memcmp(elem->data + match_offset, match, match_len))
726                         return elem;
727         }
728
729         return NULL;
730 }
731 EXPORT_SYMBOL(cfg80211_find_elem_match);
732
733 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
734                                                 const u8 *ies,
735                                                 unsigned int len)
736 {
737         const struct element *elem;
738         u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
739         int match_len = (oui_type < 0) ? 3 : sizeof(match);
740
741         if (WARN_ON(oui_type > 0xff))
742                 return NULL;
743
744         elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
745                                         match, match_len, 0);
746
747         if (!elem || elem->datalen < 4)
748                 return NULL;
749
750         return elem;
751 }
752 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
753
754 /**
755  * enum bss_compare_mode - BSS compare mode
756  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
757  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
758  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
759  */
760 enum bss_compare_mode {
761         BSS_CMP_REGULAR,
762         BSS_CMP_HIDE_ZLEN,
763         BSS_CMP_HIDE_NUL,
764 };
765
766 static int cmp_bss(struct cfg80211_bss *a,
767                    struct cfg80211_bss *b,
768                    enum bss_compare_mode mode)
769 {
770         const struct cfg80211_bss_ies *a_ies, *b_ies;
771         const u8 *ie1 = NULL;
772         const u8 *ie2 = NULL;
773         int i, r;
774
775         if (a->channel != b->channel)
776                 return b->channel->center_freq - a->channel->center_freq;
777
778         a_ies = rcu_access_pointer(a->ies);
779         if (!a_ies)
780                 return -1;
781         b_ies = rcu_access_pointer(b->ies);
782         if (!b_ies)
783                 return 1;
784
785         if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
786                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
787                                        a_ies->data, a_ies->len);
788         if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
789                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
790                                        b_ies->data, b_ies->len);
791         if (ie1 && ie2) {
792                 int mesh_id_cmp;
793
794                 if (ie1[1] == ie2[1])
795                         mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
796                 else
797                         mesh_id_cmp = ie2[1] - ie1[1];
798
799                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
800                                        a_ies->data, a_ies->len);
801                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
802                                        b_ies->data, b_ies->len);
803                 if (ie1 && ie2) {
804                         if (mesh_id_cmp)
805                                 return mesh_id_cmp;
806                         if (ie1[1] != ie2[1])
807                                 return ie2[1] - ie1[1];
808                         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
809                 }
810         }
811
812         r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
813         if (r)
814                 return r;
815
816         ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
817         ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
818
819         if (!ie1 && !ie2)
820                 return 0;
821
822         /*
823          * Note that with "hide_ssid", the function returns a match if
824          * the already-present BSS ("b") is a hidden SSID beacon for
825          * the new BSS ("a").
826          */
827
828         /* sort missing IE before (left of) present IE */
829         if (!ie1)
830                 return -1;
831         if (!ie2)
832                 return 1;
833
834         switch (mode) {
835         case BSS_CMP_HIDE_ZLEN:
836                 /*
837                  * In ZLEN mode we assume the BSS entry we're
838                  * looking for has a zero-length SSID. So if
839                  * the one we're looking at right now has that,
840                  * return 0. Otherwise, return the difference
841                  * in length, but since we're looking for the
842                  * 0-length it's really equivalent to returning
843                  * the length of the one we're looking at.
844                  *
845                  * No content comparison is needed as we assume
846                  * the content length is zero.
847                  */
848                 return ie2[1];
849         case BSS_CMP_REGULAR:
850         default:
851                 /* sort by length first, then by contents */
852                 if (ie1[1] != ie2[1])
853                         return ie2[1] - ie1[1];
854                 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
855         case BSS_CMP_HIDE_NUL:
856                 if (ie1[1] != ie2[1])
857                         return ie2[1] - ie1[1];
858                 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
859                 for (i = 0; i < ie2[1]; i++)
860                         if (ie2[i + 2])
861                                 return -1;
862                 return 0;
863         }
864 }
865
866 static bool cfg80211_bss_type_match(u16 capability,
867                                     enum nl80211_band band,
868                                     enum ieee80211_bss_type bss_type)
869 {
870         bool ret = true;
871         u16 mask, val;
872
873         if (bss_type == IEEE80211_BSS_TYPE_ANY)
874                 return ret;
875
876         if (band == NL80211_BAND_60GHZ) {
877                 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
878                 switch (bss_type) {
879                 case IEEE80211_BSS_TYPE_ESS:
880                         val = WLAN_CAPABILITY_DMG_TYPE_AP;
881                         break;
882                 case IEEE80211_BSS_TYPE_PBSS:
883                         val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
884                         break;
885                 case IEEE80211_BSS_TYPE_IBSS:
886                         val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
887                         break;
888                 default:
889                         return false;
890                 }
891         } else {
892                 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
893                 switch (bss_type) {
894                 case IEEE80211_BSS_TYPE_ESS:
895                         val = WLAN_CAPABILITY_ESS;
896                         break;
897                 case IEEE80211_BSS_TYPE_IBSS:
898                         val = WLAN_CAPABILITY_IBSS;
899                         break;
900                 case IEEE80211_BSS_TYPE_MBSS:
901                         val = 0;
902                         break;
903                 default:
904                         return false;
905                 }
906         }
907
908         ret = ((capability & mask) == val);
909         return ret;
910 }
911
912 /* Returned bss is reference counted and must be cleaned up appropriately. */
913 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
914                                       struct ieee80211_channel *channel,
915                                       const u8 *bssid,
916                                       const u8 *ssid, size_t ssid_len,
917                                       enum ieee80211_bss_type bss_type,
918                                       enum ieee80211_privacy privacy)
919 {
920         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
921         struct cfg80211_internal_bss *bss, *res = NULL;
922         unsigned long now = jiffies;
923         int bss_privacy;
924
925         trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
926                                privacy);
927
928         spin_lock_bh(&rdev->bss_lock);
929
930         list_for_each_entry(bss, &rdev->bss_list, list) {
931                 if (!cfg80211_bss_type_match(bss->pub.capability,
932                                              bss->pub.channel->band, bss_type))
933                         continue;
934
935                 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
936                 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
937                     (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
938                         continue;
939                 if (channel && bss->pub.channel != channel)
940                         continue;
941                 if (!is_valid_ether_addr(bss->pub.bssid))
942                         continue;
943                 /* Don't get expired BSS structs */
944                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
945                     !atomic_read(&bss->hold))
946                         continue;
947                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
948                         res = bss;
949                         bss_ref_get(rdev, res);
950                         break;
951                 }
952         }
953
954         spin_unlock_bh(&rdev->bss_lock);
955         if (!res)
956                 return NULL;
957         trace_cfg80211_return_bss(&res->pub);
958         return &res->pub;
959 }
960 EXPORT_SYMBOL(cfg80211_get_bss);
961
962 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
963                           struct cfg80211_internal_bss *bss)
964 {
965         struct rb_node **p = &rdev->bss_tree.rb_node;
966         struct rb_node *parent = NULL;
967         struct cfg80211_internal_bss *tbss;
968         int cmp;
969
970         while (*p) {
971                 parent = *p;
972                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
973
974                 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
975
976                 if (WARN_ON(!cmp)) {
977                         /* will sort of leak this BSS */
978                         return;
979                 }
980
981                 if (cmp < 0)
982                         p = &(*p)->rb_left;
983                 else
984                         p = &(*p)->rb_right;
985         }
986
987         rb_link_node(&bss->rbn, parent, p);
988         rb_insert_color(&bss->rbn, &rdev->bss_tree);
989 }
990
991 static struct cfg80211_internal_bss *
992 rb_find_bss(struct cfg80211_registered_device *rdev,
993             struct cfg80211_internal_bss *res,
994             enum bss_compare_mode mode)
995 {
996         struct rb_node *n = rdev->bss_tree.rb_node;
997         struct cfg80211_internal_bss *bss;
998         int r;
999
1000         while (n) {
1001                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1002                 r = cmp_bss(&res->pub, &bss->pub, mode);
1003
1004                 if (r == 0)
1005                         return bss;
1006                 else if (r < 0)
1007                         n = n->rb_left;
1008                 else
1009                         n = n->rb_right;
1010         }
1011
1012         return NULL;
1013 }
1014
1015 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1016                                    struct cfg80211_internal_bss *new)
1017 {
1018         const struct cfg80211_bss_ies *ies;
1019         struct cfg80211_internal_bss *bss;
1020         const u8 *ie;
1021         int i, ssidlen;
1022         u8 fold = 0;
1023         u32 n_entries = 0;
1024
1025         ies = rcu_access_pointer(new->pub.beacon_ies);
1026         if (WARN_ON(!ies))
1027                 return false;
1028
1029         ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1030         if (!ie) {
1031                 /* nothing to do */
1032                 return true;
1033         }
1034
1035         ssidlen = ie[1];
1036         for (i = 0; i < ssidlen; i++)
1037                 fold |= ie[2 + i];
1038
1039         if (fold) {
1040                 /* not a hidden SSID */
1041                 return true;
1042         }
1043
1044         /* This is the bad part ... */
1045
1046         list_for_each_entry(bss, &rdev->bss_list, list) {
1047                 /*
1048                  * we're iterating all the entries anyway, so take the
1049                  * opportunity to validate the list length accounting
1050                  */
1051                 n_entries++;
1052
1053                 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1054                         continue;
1055                 if (bss->pub.channel != new->pub.channel)
1056                         continue;
1057                 if (bss->pub.scan_width != new->pub.scan_width)
1058                         continue;
1059                 if (rcu_access_pointer(bss->pub.beacon_ies))
1060                         continue;
1061                 ies = rcu_access_pointer(bss->pub.ies);
1062                 if (!ies)
1063                         continue;
1064                 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1065                 if (!ie)
1066                         continue;
1067                 if (ssidlen && ie[1] != ssidlen)
1068                         continue;
1069                 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1070                         continue;
1071                 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1072                         list_del(&bss->hidden_list);
1073                 /* combine them */
1074                 list_add(&bss->hidden_list, &new->hidden_list);
1075                 bss->pub.hidden_beacon_bss = &new->pub;
1076                 new->refcount += bss->refcount;
1077                 rcu_assign_pointer(bss->pub.beacon_ies,
1078                                    new->pub.beacon_ies);
1079         }
1080
1081         WARN_ONCE(n_entries != rdev->bss_entries,
1082                   "rdev bss entries[%d]/list[len:%d] corruption\n",
1083                   rdev->bss_entries, n_entries);
1084
1085         return true;
1086 }
1087
1088 struct cfg80211_non_tx_bss {
1089         struct cfg80211_bss *tx_bss;
1090         u8 max_bssid_indicator;
1091         u8 bssid_index;
1092 };
1093
1094 /* Returned bss is reference counted and must be cleaned up appropriately. */
1095 static struct cfg80211_internal_bss *
1096 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1097                     struct cfg80211_internal_bss *tmp,
1098                     bool signal_valid)
1099 {
1100         struct cfg80211_internal_bss *found = NULL;
1101
1102         if (WARN_ON(!tmp->pub.channel))
1103                 return NULL;
1104
1105         tmp->ts = jiffies;
1106
1107         spin_lock_bh(&rdev->bss_lock);
1108
1109         if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1110                 spin_unlock_bh(&rdev->bss_lock);
1111                 return NULL;
1112         }
1113
1114         found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1115
1116         if (found) {
1117                 /* Update IEs */
1118                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1119                         const struct cfg80211_bss_ies *old;
1120
1121                         old = rcu_access_pointer(found->pub.proberesp_ies);
1122
1123                         rcu_assign_pointer(found->pub.proberesp_ies,
1124                                            tmp->pub.proberesp_ies);
1125                         /* Override possible earlier Beacon frame IEs */
1126                         rcu_assign_pointer(found->pub.ies,
1127                                            tmp->pub.proberesp_ies);
1128                         if (old)
1129                                 kfree_rcu((struct cfg80211_bss_ies *)old,
1130                                           rcu_head);
1131                 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
1132                         const struct cfg80211_bss_ies *old;
1133                         struct cfg80211_internal_bss *bss;
1134
1135                         if (found->pub.hidden_beacon_bss &&
1136                             !list_empty(&found->hidden_list)) {
1137                                 const struct cfg80211_bss_ies *f;
1138
1139                                 /*
1140                                  * The found BSS struct is one of the probe
1141                                  * response members of a group, but we're
1142                                  * receiving a beacon (beacon_ies in the tmp
1143                                  * bss is used). This can only mean that the
1144                                  * AP changed its beacon from not having an
1145                                  * SSID to showing it, which is confusing so
1146                                  * drop this information.
1147                                  */
1148
1149                                 f = rcu_access_pointer(tmp->pub.beacon_ies);
1150                                 kfree_rcu((struct cfg80211_bss_ies *)f,
1151                                           rcu_head);
1152                                 goto drop;
1153                         }
1154
1155                         old = rcu_access_pointer(found->pub.beacon_ies);
1156
1157                         rcu_assign_pointer(found->pub.beacon_ies,
1158                                            tmp->pub.beacon_ies);
1159
1160                         /* Override IEs if they were from a beacon before */
1161                         if (old == rcu_access_pointer(found->pub.ies))
1162                                 rcu_assign_pointer(found->pub.ies,
1163                                                    tmp->pub.beacon_ies);
1164
1165                         /* Assign beacon IEs to all sub entries */
1166                         list_for_each_entry(bss, &found->hidden_list,
1167                                             hidden_list) {
1168                                 const struct cfg80211_bss_ies *ies;
1169
1170                                 ies = rcu_access_pointer(bss->pub.beacon_ies);
1171                                 WARN_ON(ies != old);
1172
1173                                 rcu_assign_pointer(bss->pub.beacon_ies,
1174                                                    tmp->pub.beacon_ies);
1175                         }
1176
1177                         if (old)
1178                                 kfree_rcu((struct cfg80211_bss_ies *)old,
1179                                           rcu_head);
1180                 }
1181
1182                 found->pub.beacon_interval = tmp->pub.beacon_interval;
1183                 /*
1184                  * don't update the signal if beacon was heard on
1185                  * adjacent channel.
1186                  */
1187                 if (signal_valid)
1188                         found->pub.signal = tmp->pub.signal;
1189                 found->pub.capability = tmp->pub.capability;
1190                 found->ts = tmp->ts;
1191                 found->ts_boottime = tmp->ts_boottime;
1192                 found->parent_tsf = tmp->parent_tsf;
1193                 found->pub.chains = tmp->pub.chains;
1194                 memcpy(found->pub.chain_signal, tmp->pub.chain_signal,
1195                        IEEE80211_MAX_CHAINS);
1196                 ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
1197                 found->pub.max_bssid_indicator = tmp->pub.max_bssid_indicator;
1198                 found->pub.bssid_index = tmp->pub.bssid_index;
1199         } else {
1200                 struct cfg80211_internal_bss *new;
1201                 struct cfg80211_internal_bss *hidden;
1202                 struct cfg80211_bss_ies *ies;
1203
1204                 /*
1205                  * create a copy -- the "res" variable that is passed in
1206                  * is allocated on the stack since it's not needed in the
1207                  * more common case of an update
1208                  */
1209                 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1210                               GFP_ATOMIC);
1211                 if (!new) {
1212                         ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1213                         if (ies)
1214                                 kfree_rcu(ies, rcu_head);
1215                         ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1216                         if (ies)
1217                                 kfree_rcu(ies, rcu_head);
1218                         goto drop;
1219                 }
1220                 memcpy(new, tmp, sizeof(*new));
1221                 new->refcount = 1;
1222                 INIT_LIST_HEAD(&new->hidden_list);
1223                 INIT_LIST_HEAD(&new->pub.nontrans_list);
1224
1225                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1226                         hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1227                         if (!hidden)
1228                                 hidden = rb_find_bss(rdev, tmp,
1229                                                      BSS_CMP_HIDE_NUL);
1230                         if (hidden) {
1231                                 new->pub.hidden_beacon_bss = &hidden->pub;
1232                                 list_add(&new->hidden_list,
1233                                          &hidden->hidden_list);
1234                                 hidden->refcount++;
1235                                 rcu_assign_pointer(new->pub.beacon_ies,
1236                                                    hidden->pub.beacon_ies);
1237                         }
1238                 } else {
1239                         /*
1240                          * Ok so we found a beacon, and don't have an entry. If
1241                          * it's a beacon with hidden SSID, we might be in for an
1242                          * expensive search for any probe responses that should
1243                          * be grouped with this beacon for updates ...
1244                          */
1245                         if (!cfg80211_combine_bsses(rdev, new)) {
1246                                 kfree(new);
1247                                 goto drop;
1248                         }
1249                 }
1250
1251                 if (rdev->bss_entries >= bss_entries_limit &&
1252                     !cfg80211_bss_expire_oldest(rdev)) {
1253                         kfree(new);
1254                         goto drop;
1255                 }
1256
1257                 /* This must be before the call to bss_ref_get */
1258                 if (tmp->pub.transmitted_bss) {
1259                         struct cfg80211_internal_bss *pbss =
1260                                 container_of(tmp->pub.transmitted_bss,
1261                                              struct cfg80211_internal_bss,
1262                                              pub);
1263
1264                         new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1265                         bss_ref_get(rdev, pbss);
1266                 }
1267
1268                 list_add_tail(&new->list, &rdev->bss_list);
1269                 rdev->bss_entries++;
1270                 rb_insert_bss(rdev, new);
1271                 found = new;
1272         }
1273
1274         rdev->bss_generation++;
1275         bss_ref_get(rdev, found);
1276         spin_unlock_bh(&rdev->bss_lock);
1277
1278         return found;
1279  drop:
1280         spin_unlock_bh(&rdev->bss_lock);
1281         return NULL;
1282 }
1283
1284 /*
1285  * Update RX channel information based on the available frame payload
1286  * information. This is mainly for the 2.4 GHz band where frames can be received
1287  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1288  * element to indicate the current (transmitting) channel, but this might also
1289  * be needed on other bands if RX frequency does not match with the actual
1290  * operating channel of a BSS.
1291  */
1292 static struct ieee80211_channel *
1293 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1294                          struct ieee80211_channel *channel,
1295                          enum nl80211_bss_scan_width scan_width)
1296 {
1297         const u8 *tmp;
1298         u32 freq;
1299         int channel_number = -1;
1300         struct ieee80211_channel *alt_channel;
1301
1302         tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
1303         if (tmp && tmp[1] == 1) {
1304                 channel_number = tmp[2];
1305         } else {
1306                 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
1307                 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
1308                         struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
1309
1310                         channel_number = htop->primary_chan;
1311                 }
1312         }
1313
1314         if (channel_number < 0) {
1315                 /* No channel information in frame payload */
1316                 return channel;
1317         }
1318
1319         freq = ieee80211_channel_to_frequency(channel_number, channel->band);
1320         alt_channel = ieee80211_get_channel(wiphy, freq);
1321         if (!alt_channel) {
1322                 if (channel->band == NL80211_BAND_2GHZ) {
1323                         /*
1324                          * Better not allow unexpected channels when that could
1325                          * be going beyond the 1-11 range (e.g., discovering
1326                          * BSS on channel 12 when radio is configured for
1327                          * channel 11.
1328                          */
1329                         return NULL;
1330                 }
1331
1332                 /* No match for the payload channel number - ignore it */
1333                 return channel;
1334         }
1335
1336         if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1337             scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1338                 /*
1339                  * Ignore channel number in 5 and 10 MHz channels where there
1340                  * may not be an n:1 or 1:n mapping between frequencies and
1341                  * channel numbers.
1342                  */
1343                 return channel;
1344         }
1345
1346         /*
1347          * Use the channel determined through the payload channel number
1348          * instead of the RX channel reported by the driver.
1349          */
1350         if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1351                 return NULL;
1352         return alt_channel;
1353 }
1354
1355 /* Returned bss is reference counted and must be cleaned up appropriately. */
1356 static struct cfg80211_bss *
1357 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1358                                 struct cfg80211_inform_bss *data,
1359                                 enum cfg80211_bss_frame_type ftype,
1360                                 const u8 *bssid, u64 tsf, u16 capability,
1361                                 u16 beacon_interval, const u8 *ie, size_t ielen,
1362                                 struct cfg80211_non_tx_bss *non_tx_data,
1363                                 gfp_t gfp)
1364 {
1365         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1366         struct cfg80211_bss_ies *ies;
1367         struct ieee80211_channel *channel;
1368         struct cfg80211_internal_bss tmp = {}, *res;
1369         int bss_type;
1370         bool signal_valid;
1371
1372         if (WARN_ON(!wiphy))
1373                 return NULL;
1374
1375         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1376                     (data->signal < 0 || data->signal > 100)))
1377                 return NULL;
1378
1379         channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1380                                            data->scan_width);
1381         if (!channel)
1382                 return NULL;
1383
1384         memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1385         tmp.pub.channel = channel;
1386         tmp.pub.scan_width = data->scan_width;
1387         tmp.pub.signal = data->signal;
1388         tmp.pub.beacon_interval = beacon_interval;
1389         tmp.pub.capability = capability;
1390         tmp.ts_boottime = data->boottime_ns;
1391         if (non_tx_data) {
1392                 tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1393                 tmp.pub.bssid_index = non_tx_data->bssid_index;
1394                 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1395         }
1396
1397         /*
1398          * If we do not know here whether the IEs are from a Beacon or Probe
1399          * Response frame, we need to pick one of the options and only use it
1400          * with the driver that does not provide the full Beacon/Probe Response
1401          * frame. Use Beacon frame pointer to avoid indicating that this should
1402          * override the IEs pointer should we have received an earlier
1403          * indication of Probe Response data.
1404          */
1405         ies = kzalloc(sizeof(*ies) + ielen, gfp);
1406         if (!ies)
1407                 return NULL;
1408         ies->len = ielen;
1409         ies->tsf = tsf;
1410         ies->from_beacon = false;
1411         memcpy(ies->data, ie, ielen);
1412
1413         switch (ftype) {
1414         case CFG80211_BSS_FTYPE_BEACON:
1415                 ies->from_beacon = true;
1416                 /* fall through */
1417         case CFG80211_BSS_FTYPE_UNKNOWN:
1418                 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1419                 break;
1420         case CFG80211_BSS_FTYPE_PRESP:
1421                 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1422                 break;
1423         }
1424         rcu_assign_pointer(tmp.pub.ies, ies);
1425
1426         signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1427                 wiphy->max_adj_channel_rssi_comp;
1428         res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1429         if (!res)
1430                 return NULL;
1431
1432         if (channel->band == NL80211_BAND_60GHZ) {
1433                 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1434                 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1435                     bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1436                         regulatory_hint_found_beacon(wiphy, channel, gfp);
1437         } else {
1438                 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1439                         regulatory_hint_found_beacon(wiphy, channel, gfp);
1440         }
1441
1442         if (non_tx_data && non_tx_data->tx_bss) {
1443                 /* this is a nontransmitting bss, we need to add it to
1444                  * transmitting bss' list if it is not there
1445                  */
1446                 if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
1447                                                &res->pub)) {
1448                         if (__cfg80211_unlink_bss(rdev, res))
1449                                 rdev->bss_generation++;
1450                 }
1451         }
1452
1453         trace_cfg80211_return_bss(&res->pub);
1454         /* cfg80211_bss_update gives us a referenced result */
1455         return &res->pub;
1456 }
1457
1458 static const struct element
1459 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
1460                                    const struct element *mbssid_elem,
1461                                    const struct element *sub_elem)
1462 {
1463         const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
1464         const struct element *next_mbssid;
1465         const struct element *next_sub;
1466
1467         next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
1468                                          mbssid_end,
1469                                          ielen - (mbssid_end - ie));
1470
1471         /*
1472          * If is is not the last subelement in current MBSSID IE or there isn't
1473          * a next MBSSID IE - profile is complete.
1474         */
1475         if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
1476             !next_mbssid)
1477                 return NULL;
1478
1479         /* For any length error, just return NULL */
1480
1481         if (next_mbssid->datalen < 4)
1482                 return NULL;
1483
1484         next_sub = (void *)&next_mbssid->data[1];
1485
1486         if (next_mbssid->data + next_mbssid->datalen <
1487             next_sub->data + next_sub->datalen)
1488                 return NULL;
1489
1490         if (next_sub->id != 0 || next_sub->datalen < 2)
1491                 return NULL;
1492
1493         /*
1494          * Check if the first element in the next sub element is a start
1495          * of a new profile
1496          */
1497         return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
1498                NULL : next_mbssid;
1499 }
1500
1501 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
1502                               const struct element *mbssid_elem,
1503                               const struct element *sub_elem,
1504                               u8 *merged_ie, size_t max_copy_len)
1505 {
1506         size_t copied_len = sub_elem->datalen;
1507         const struct element *next_mbssid;
1508
1509         if (sub_elem->datalen > max_copy_len)
1510                 return 0;
1511
1512         memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
1513
1514         while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
1515                                                                 mbssid_elem,
1516                                                                 sub_elem))) {
1517                 const struct element *next_sub = (void *)&next_mbssid->data[1];
1518
1519                 if (copied_len + next_sub->datalen > max_copy_len)
1520                         break;
1521                 memcpy(merged_ie + copied_len, next_sub->data,
1522                        next_sub->datalen);
1523                 copied_len += next_sub->datalen;
1524         }
1525
1526         return copied_len;
1527 }
1528 EXPORT_SYMBOL(cfg80211_merge_profile);
1529
1530 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
1531                                        struct cfg80211_inform_bss *data,
1532                                        enum cfg80211_bss_frame_type ftype,
1533                                        const u8 *bssid, u64 tsf,
1534                                        u16 beacon_interval, const u8 *ie,
1535                                        size_t ielen,
1536                                        struct cfg80211_non_tx_bss *non_tx_data,
1537                                        gfp_t gfp)
1538 {
1539         const u8 *mbssid_index_ie;
1540         const struct element *elem, *sub;
1541         size_t new_ie_len;
1542         u8 new_bssid[ETH_ALEN];
1543         u8 *new_ie, *profile;
1544         u64 seen_indices = 0;
1545         u16 capability;
1546         struct cfg80211_bss *bss;
1547
1548         if (!non_tx_data)
1549                 return;
1550         if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
1551                 return;
1552         if (!wiphy->support_mbssid)
1553                 return;
1554         if (wiphy->support_only_he_mbssid &&
1555             !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
1556                 return;
1557
1558         new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
1559         if (!new_ie)
1560                 return;
1561
1562         profile = kmalloc(ielen, gfp);
1563         if (!profile)
1564                 goto out;
1565
1566         for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
1567                 if (elem->datalen < 4)
1568                         continue;
1569                 for_each_element(sub, elem->data + 1, elem->datalen - 1) {
1570                         u8 profile_len;
1571
1572                         if (sub->id != 0 || sub->datalen < 4) {
1573                                 /* not a valid BSS profile */
1574                                 continue;
1575                         }
1576
1577                         if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
1578                             sub->data[1] != 2) {
1579                                 /* The first element within the Nontransmitted
1580                                  * BSSID Profile is not the Nontransmitted
1581                                  * BSSID Capability element.
1582                                  */
1583                                 continue;
1584                         }
1585
1586                         memset(profile, 0, ielen);
1587                         profile_len = cfg80211_merge_profile(ie, ielen,
1588                                                              elem,
1589                                                              sub,
1590                                                              profile,
1591                                                              ielen);
1592
1593                         /* found a Nontransmitted BSSID Profile */
1594                         mbssid_index_ie = cfg80211_find_ie
1595                                 (WLAN_EID_MULTI_BSSID_IDX,
1596                                  profile, profile_len);
1597                         if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
1598                             mbssid_index_ie[2] == 0 ||
1599                             mbssid_index_ie[2] > 46) {
1600                                 /* No valid Multiple BSSID-Index element */
1601                                 continue;
1602                         }
1603
1604                         if (seen_indices & BIT(mbssid_index_ie[2]))
1605                                 /* We don't support legacy split of a profile */
1606                                 net_dbg_ratelimited("Partial info for BSSID index %d\n",
1607                                                     mbssid_index_ie[2]);
1608
1609                         seen_indices |= BIT(mbssid_index_ie[2]);
1610
1611                         non_tx_data->bssid_index = mbssid_index_ie[2];
1612                         non_tx_data->max_bssid_indicator = elem->data[0];
1613
1614                         cfg80211_gen_new_bssid(bssid,
1615                                                non_tx_data->max_bssid_indicator,
1616                                                non_tx_data->bssid_index,
1617                                                new_bssid);
1618                         memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
1619                         new_ie_len = cfg80211_gen_new_ie(ie, ielen,
1620                                                          profile,
1621                                                          profile_len, new_ie,
1622                                                          gfp);
1623                         if (!new_ie_len)
1624                                 continue;
1625
1626                         capability = get_unaligned_le16(profile + 2);
1627                         bss = cfg80211_inform_single_bss_data(wiphy, data,
1628                                                               ftype,
1629                                                               new_bssid, tsf,
1630                                                               capability,
1631                                                               beacon_interval,
1632                                                               new_ie,
1633                                                               new_ie_len,
1634                                                               non_tx_data,
1635                                                               gfp);
1636                         if (!bss)
1637                                 break;
1638                         cfg80211_put_bss(wiphy, bss);
1639                 }
1640         }
1641
1642 out:
1643         kfree(new_ie);
1644         kfree(profile);
1645 }
1646
1647 struct cfg80211_bss *
1648 cfg80211_inform_bss_data(struct wiphy *wiphy,
1649                          struct cfg80211_inform_bss *data,
1650                          enum cfg80211_bss_frame_type ftype,
1651                          const u8 *bssid, u64 tsf, u16 capability,
1652                          u16 beacon_interval, const u8 *ie, size_t ielen,
1653                          gfp_t gfp)
1654 {
1655         struct cfg80211_bss *res;
1656         struct cfg80211_non_tx_bss non_tx_data;
1657
1658         res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
1659                                               capability, beacon_interval, ie,
1660                                               ielen, NULL, gfp);
1661         non_tx_data.tx_bss = res;
1662         cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
1663                                    beacon_interval, ie, ielen, &non_tx_data,
1664                                    gfp);
1665         return res;
1666 }
1667 EXPORT_SYMBOL(cfg80211_inform_bss_data);
1668
1669 static void
1670 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
1671                                  struct cfg80211_inform_bss *data,
1672                                  struct ieee80211_mgmt *mgmt, size_t len,
1673                                  struct cfg80211_non_tx_bss *non_tx_data,
1674                                  gfp_t gfp)
1675 {
1676         enum cfg80211_bss_frame_type ftype;
1677         const u8 *ie = mgmt->u.probe_resp.variable;
1678         size_t ielen = len - offsetof(struct ieee80211_mgmt,
1679                                       u.probe_resp.variable);
1680
1681         ftype = ieee80211_is_beacon(mgmt->frame_control) ?
1682                 CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
1683
1684         cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
1685                                    le64_to_cpu(mgmt->u.probe_resp.timestamp),
1686                                    le16_to_cpu(mgmt->u.probe_resp.beacon_int),
1687                                    ie, ielen, non_tx_data, gfp);
1688 }
1689
1690 static void
1691 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
1692                                    struct cfg80211_bss *nontrans_bss,
1693                                    struct ieee80211_mgmt *mgmt, size_t len,
1694                                    gfp_t gfp)
1695 {
1696         u8 *ie, *new_ie, *pos;
1697         const u8 *nontrans_ssid, *trans_ssid, *mbssid;
1698         size_t ielen = len - offsetof(struct ieee80211_mgmt,
1699                                       u.probe_resp.variable);
1700         size_t new_ie_len;
1701         struct cfg80211_bss_ies *new_ies;
1702         const struct cfg80211_bss_ies *old;
1703         u8 cpy_len;
1704
1705         ie = mgmt->u.probe_resp.variable;
1706
1707         new_ie_len = ielen;
1708         trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
1709         if (!trans_ssid)
1710                 return;
1711         new_ie_len -= trans_ssid[1];
1712         mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
1713         if (!mbssid)
1714                 return;
1715         new_ie_len -= mbssid[1];
1716         rcu_read_lock();
1717         nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
1718         if (!nontrans_ssid) {
1719                 rcu_read_unlock();
1720                 return;
1721         }
1722         new_ie_len += nontrans_ssid[1];
1723         rcu_read_unlock();
1724
1725         /* generate new ie for nontrans BSS
1726          * 1. replace SSID with nontrans BSS' SSID
1727          * 2. skip MBSSID IE
1728          */
1729         new_ie = kzalloc(new_ie_len, gfp);
1730         if (!new_ie)
1731                 return;
1732         new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, gfp);
1733         if (!new_ies)
1734                 goto out_free;
1735
1736         pos = new_ie;
1737
1738         /* copy the nontransmitted SSID */
1739         cpy_len = nontrans_ssid[1] + 2;
1740         memcpy(pos, nontrans_ssid, cpy_len);
1741         pos += cpy_len;
1742         /* copy the IEs between SSID and MBSSID */
1743         cpy_len = trans_ssid[1] + 2;
1744         memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
1745         pos += (mbssid - (trans_ssid + cpy_len));
1746         /* copy the IEs after MBSSID */
1747         cpy_len = mbssid[1] + 2;
1748         memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
1749
1750         /* update ie */
1751         new_ies->len = new_ie_len;
1752         new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1753         new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1754         memcpy(new_ies->data, new_ie, new_ie_len);
1755         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
1756                 old = rcu_access_pointer(nontrans_bss->proberesp_ies);
1757                 rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
1758                 rcu_assign_pointer(nontrans_bss->ies, new_ies);
1759                 if (old)
1760                         kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1761         } else {
1762                 old = rcu_access_pointer(nontrans_bss->beacon_ies);
1763                 rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
1764                 rcu_assign_pointer(nontrans_bss->ies, new_ies);
1765                 if (old)
1766                         kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1767         }
1768
1769 out_free:
1770         kfree(new_ie);
1771 }
1772
1773 /* cfg80211_inform_bss_width_frame helper */
1774 static struct cfg80211_bss *
1775 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
1776                                       struct cfg80211_inform_bss *data,
1777                                       struct ieee80211_mgmt *mgmt, size_t len,
1778                                       struct cfg80211_non_tx_bss *non_tx_data,
1779                                       gfp_t gfp)
1780 {
1781         struct cfg80211_internal_bss tmp = {}, *res;
1782         struct cfg80211_bss_ies *ies;
1783         struct ieee80211_channel *channel;
1784         bool signal_valid;
1785         size_t ielen = len - offsetof(struct ieee80211_mgmt,
1786                                       u.probe_resp.variable);
1787         int bss_type;
1788
1789         BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1790                         offsetof(struct ieee80211_mgmt, u.beacon.variable));
1791
1792         trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1793
1794         if (WARN_ON(!mgmt))
1795                 return NULL;
1796
1797         if (WARN_ON(!wiphy))
1798                 return NULL;
1799
1800         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1801                     (data->signal < 0 || data->signal > 100)))
1802                 return NULL;
1803
1804         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1805                 return NULL;
1806
1807         channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1808                                            ielen, data->chan, data->scan_width);
1809         if (!channel)
1810                 return NULL;
1811
1812         ies = kzalloc(sizeof(*ies) + ielen, gfp);
1813         if (!ies)
1814                 return NULL;
1815         ies->len = ielen;
1816         ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1817         ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1818         memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1819
1820         if (ieee80211_is_probe_resp(mgmt->frame_control))
1821                 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1822         else
1823                 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1824         rcu_assign_pointer(tmp.pub.ies, ies);
1825
1826         memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1827         tmp.pub.channel = channel;
1828         tmp.pub.scan_width = data->scan_width;
1829         tmp.pub.signal = data->signal;
1830         tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1831         tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1832         tmp.ts_boottime = data->boottime_ns;
1833         tmp.parent_tsf = data->parent_tsf;
1834         tmp.pub.chains = data->chains;
1835         memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
1836         ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1837         if (non_tx_data) {
1838                 tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1839                 tmp.pub.bssid_index = non_tx_data->bssid_index;
1840                 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1841         }
1842
1843         signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1844                 wiphy->max_adj_channel_rssi_comp;
1845         res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1846         if (!res)
1847                 return NULL;
1848
1849         if (channel->band == NL80211_BAND_60GHZ) {
1850                 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1851                 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1852                     bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1853                         regulatory_hint_found_beacon(wiphy, channel, gfp);
1854         } else {
1855                 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1856                         regulatory_hint_found_beacon(wiphy, channel, gfp);
1857         }
1858
1859         trace_cfg80211_return_bss(&res->pub);
1860         /* cfg80211_bss_update gives us a referenced result */
1861         return &res->pub;
1862 }
1863
1864 struct cfg80211_bss *
1865 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1866                                struct cfg80211_inform_bss *data,
1867                                struct ieee80211_mgmt *mgmt, size_t len,
1868                                gfp_t gfp)
1869 {
1870         struct cfg80211_bss *res, *tmp_bss;
1871         const u8 *ie = mgmt->u.probe_resp.variable;
1872         const struct cfg80211_bss_ies *ies1, *ies2;
1873         size_t ielen = len - offsetof(struct ieee80211_mgmt,
1874                                       u.probe_resp.variable);
1875         struct cfg80211_non_tx_bss non_tx_data;
1876
1877         res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
1878                                                     len, NULL, gfp);
1879         if (!res || !wiphy->support_mbssid ||
1880             !cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
1881                 return res;
1882         if (wiphy->support_only_he_mbssid &&
1883             !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
1884                 return res;
1885
1886         non_tx_data.tx_bss = res;
1887         /* process each non-transmitting bss */
1888         cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
1889                                          &non_tx_data, gfp);
1890
1891         /* check if the res has other nontransmitting bss which is not
1892          * in MBSSID IE
1893          */
1894         ies1 = rcu_access_pointer(res->ies);
1895
1896         /* go through nontrans_list, if the timestamp of the BSS is
1897          * earlier than the timestamp of the transmitting BSS then
1898          * update it
1899          */
1900         list_for_each_entry(tmp_bss, &res->nontrans_list,
1901                             nontrans_list) {
1902                 ies2 = rcu_access_pointer(tmp_bss->ies);
1903                 if (ies2->tsf < ies1->tsf)
1904                         cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
1905                                                            mgmt, len, gfp);
1906         }
1907
1908         return res;
1909 }
1910 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1911
1912 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1913 {
1914         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1915         struct cfg80211_internal_bss *bss;
1916
1917         if (!pub)
1918                 return;
1919
1920         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1921
1922         spin_lock_bh(&rdev->bss_lock);
1923         bss_ref_get(rdev, bss);
1924         spin_unlock_bh(&rdev->bss_lock);
1925 }
1926 EXPORT_SYMBOL(cfg80211_ref_bss);
1927
1928 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1929 {
1930         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1931         struct cfg80211_internal_bss *bss;
1932
1933         if (!pub)
1934                 return;
1935
1936         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1937
1938         spin_lock_bh(&rdev->bss_lock);
1939         bss_ref_put(rdev, bss);
1940         spin_unlock_bh(&rdev->bss_lock);
1941 }
1942 EXPORT_SYMBOL(cfg80211_put_bss);
1943
1944 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1945 {
1946         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1947         struct cfg80211_internal_bss *bss, *tmp1;
1948         struct cfg80211_bss *nontrans_bss, *tmp;
1949
1950         if (WARN_ON(!pub))
1951                 return;
1952
1953         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1954
1955         spin_lock_bh(&rdev->bss_lock);
1956         if (list_empty(&bss->list))
1957                 goto out;
1958
1959         list_for_each_entry_safe(nontrans_bss, tmp,
1960                                  &pub->nontrans_list,
1961                                  nontrans_list) {
1962                 tmp1 = container_of(nontrans_bss,
1963                                     struct cfg80211_internal_bss, pub);
1964                 if (__cfg80211_unlink_bss(rdev, tmp1))
1965                         rdev->bss_generation++;
1966         }
1967
1968         if (__cfg80211_unlink_bss(rdev, bss))
1969                 rdev->bss_generation++;
1970 out:
1971         spin_unlock_bh(&rdev->bss_lock);
1972 }
1973 EXPORT_SYMBOL(cfg80211_unlink_bss);
1974
1975 #ifdef CONFIG_CFG80211_WEXT
1976 static struct cfg80211_registered_device *
1977 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1978 {
1979         struct cfg80211_registered_device *rdev;
1980         struct net_device *dev;
1981
1982         ASSERT_RTNL();
1983
1984         dev = dev_get_by_index(net, ifindex);
1985         if (!dev)
1986                 return ERR_PTR(-ENODEV);
1987         if (dev->ieee80211_ptr)
1988                 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1989         else
1990                 rdev = ERR_PTR(-ENODEV);
1991         dev_put(dev);
1992         return rdev;
1993 }
1994
1995 int cfg80211_wext_siwscan(struct net_device *dev,
1996                           struct iw_request_info *info,
1997                           union iwreq_data *wrqu, char *extra)
1998 {
1999         struct cfg80211_registered_device *rdev;
2000         struct wiphy *wiphy;
2001         struct iw_scan_req *wreq = NULL;
2002         struct cfg80211_scan_request *creq = NULL;
2003         int i, err, n_channels = 0;
2004         enum nl80211_band band;
2005
2006         if (!netif_running(dev))
2007                 return -ENETDOWN;
2008
2009         if (wrqu->data.length == sizeof(struct iw_scan_req))
2010                 wreq = (struct iw_scan_req *)extra;
2011
2012         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2013
2014         if (IS_ERR(rdev))
2015                 return PTR_ERR(rdev);
2016
2017         if (rdev->scan_req || rdev->scan_msg) {
2018                 err = -EBUSY;
2019                 goto out;
2020         }
2021
2022         wiphy = &rdev->wiphy;
2023
2024         /* Determine number of channels, needed to allocate creq */
2025         if (wreq && wreq->num_channels)
2026                 n_channels = wreq->num_channels;
2027         else
2028                 n_channels = ieee80211_get_num_supported_channels(wiphy);
2029
2030         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2031                        n_channels * sizeof(void *),
2032                        GFP_ATOMIC);
2033         if (!creq) {
2034                 err = -ENOMEM;
2035                 goto out;
2036         }
2037
2038         creq->wiphy = wiphy;
2039         creq->wdev = dev->ieee80211_ptr;
2040         /* SSIDs come after channels */
2041         creq->ssids = (void *)&creq->channels[n_channels];
2042         creq->n_channels = n_channels;
2043         creq->n_ssids = 1;
2044         creq->scan_start = jiffies;
2045
2046         /* translate "Scan on frequencies" request */
2047         i = 0;
2048         for (band = 0; band < NUM_NL80211_BANDS; band++) {
2049                 int j;
2050
2051                 if (!wiphy->bands[band])
2052                         continue;
2053
2054                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2055                         /* ignore disabled channels */
2056                         if (wiphy->bands[band]->channels[j].flags &
2057                                                 IEEE80211_CHAN_DISABLED)
2058                                 continue;
2059
2060                         /* If we have a wireless request structure and the
2061                          * wireless request specifies frequencies, then search
2062                          * for the matching hardware channel.
2063                          */
2064                         if (wreq && wreq->num_channels) {
2065                                 int k;
2066                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2067                                 for (k = 0; k < wreq->num_channels; k++) {
2068                                         struct iw_freq *freq =
2069                                                 &wreq->channel_list[k];
2070                                         int wext_freq =
2071                                                 cfg80211_wext_freq(freq);
2072
2073                                         if (wext_freq == wiphy_freq)
2074                                                 goto wext_freq_found;
2075                                 }
2076                                 goto wext_freq_not_found;
2077                         }
2078
2079                 wext_freq_found:
2080                         creq->channels[i] = &wiphy->bands[band]->channels[j];
2081                         i++;
2082                 wext_freq_not_found: ;
2083                 }
2084         }
2085         /* No channels found? */
2086         if (!i) {
2087                 err = -EINVAL;
2088                 goto out;
2089         }
2090
2091         /* Set real number of channels specified in creq->channels[] */
2092         creq->n_channels = i;
2093
2094         /* translate "Scan for SSID" request */
2095         if (wreq) {
2096                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2097                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2098                                 err = -EINVAL;
2099                                 goto out;
2100                         }
2101                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2102                         creq->ssids[0].ssid_len = wreq->essid_len;
2103                 }
2104                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2105                         creq->n_ssids = 0;
2106         }
2107
2108         for (i = 0; i < NUM_NL80211_BANDS; i++)
2109                 if (wiphy->bands[i])
2110                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2111
2112         eth_broadcast_addr(creq->bssid);
2113
2114         rdev->scan_req = creq;
2115         err = rdev_scan(rdev, creq);
2116         if (err) {
2117                 rdev->scan_req = NULL;
2118                 /* creq will be freed below */
2119         } else {
2120                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2121                 /* creq now owned by driver */
2122                 creq = NULL;
2123                 dev_hold(dev);
2124         }
2125  out:
2126         kfree(creq);
2127         return err;
2128 }
2129 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2130
2131 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2132                                     const struct cfg80211_bss_ies *ies,
2133                                     char *current_ev, char *end_buf)
2134 {
2135         const u8 *pos, *end, *next;
2136         struct iw_event iwe;
2137
2138         if (!ies)
2139                 return current_ev;
2140
2141         /*
2142          * If needed, fragment the IEs buffer (at IE boundaries) into short
2143          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2144          */
2145         pos = ies->data;
2146         end = pos + ies->len;
2147
2148         while (end - pos > IW_GENERIC_IE_MAX) {
2149                 next = pos + 2 + pos[1];
2150                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2151                         next = next + 2 + next[1];
2152
2153                 memset(&iwe, 0, sizeof(iwe));
2154                 iwe.cmd = IWEVGENIE;
2155                 iwe.u.data.length = next - pos;
2156                 current_ev = iwe_stream_add_point_check(info, current_ev,
2157                                                         end_buf, &iwe,
2158                                                         (void *)pos);
2159                 if (IS_ERR(current_ev))
2160                         return current_ev;
2161                 pos = next;
2162         }
2163
2164         if (end > pos) {
2165                 memset(&iwe, 0, sizeof(iwe));
2166                 iwe.cmd = IWEVGENIE;
2167                 iwe.u.data.length = end - pos;
2168                 current_ev = iwe_stream_add_point_check(info, current_ev,
2169                                                         end_buf, &iwe,
2170                                                         (void *)pos);
2171                 if (IS_ERR(current_ev))
2172                         return current_ev;
2173         }
2174
2175         return current_ev;
2176 }
2177
2178 static char *
2179 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2180               struct cfg80211_internal_bss *bss, char *current_ev,
2181               char *end_buf)
2182 {
2183         const struct cfg80211_bss_ies *ies;
2184         struct iw_event iwe;
2185         const u8 *ie;
2186         u8 buf[50];
2187         u8 *cfg, *p, *tmp;
2188         int rem, i, sig;
2189         bool ismesh = false;
2190
2191         memset(&iwe, 0, sizeof(iwe));
2192         iwe.cmd = SIOCGIWAP;
2193         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2194         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2195         current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2196                                                 IW_EV_ADDR_LEN);
2197         if (IS_ERR(current_ev))
2198                 return current_ev;
2199
2200         memset(&iwe, 0, sizeof(iwe));
2201         iwe.cmd = SIOCGIWFREQ;
2202         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2203         iwe.u.freq.e = 0;
2204         current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2205                                                 IW_EV_FREQ_LEN);
2206         if (IS_ERR(current_ev))
2207                 return current_ev;
2208
2209         memset(&iwe, 0, sizeof(iwe));
2210         iwe.cmd = SIOCGIWFREQ;
2211         iwe.u.freq.m = bss->pub.channel->center_freq;
2212         iwe.u.freq.e = 6;
2213         current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2214                                                 IW_EV_FREQ_LEN);
2215         if (IS_ERR(current_ev))
2216                 return current_ev;
2217
2218         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2219                 memset(&iwe, 0, sizeof(iwe));
2220                 iwe.cmd = IWEVQUAL;
2221                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2222                                      IW_QUAL_NOISE_INVALID |
2223                                      IW_QUAL_QUAL_UPDATED;
2224                 switch (wiphy->signal_type) {
2225                 case CFG80211_SIGNAL_TYPE_MBM:
2226                         sig = bss->pub.signal / 100;
2227                         iwe.u.qual.level = sig;
2228                         iwe.u.qual.updated |= IW_QUAL_DBM;
2229                         if (sig < -110)         /* rather bad */
2230                                 sig = -110;
2231                         else if (sig > -40)     /* perfect */
2232                                 sig = -40;
2233                         /* will give a range of 0 .. 70 */
2234                         iwe.u.qual.qual = sig + 110;
2235                         break;
2236                 case CFG80211_SIGNAL_TYPE_UNSPEC:
2237                         iwe.u.qual.level = bss->pub.signal;
2238                         /* will give range 0 .. 100 */
2239                         iwe.u.qual.qual = bss->pub.signal;
2240                         break;
2241                 default:
2242                         /* not reached */
2243                         break;
2244                 }
2245                 current_ev = iwe_stream_add_event_check(info, current_ev,
2246                                                         end_buf, &iwe,
2247                                                         IW_EV_QUAL_LEN);
2248                 if (IS_ERR(current_ev))
2249                         return current_ev;
2250         }
2251
2252         memset(&iwe, 0, sizeof(iwe));
2253         iwe.cmd = SIOCGIWENCODE;
2254         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
2255                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
2256         else
2257                 iwe.u.data.flags = IW_ENCODE_DISABLED;
2258         iwe.u.data.length = 0;
2259         current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2260                                                 &iwe, "");
2261         if (IS_ERR(current_ev))
2262                 return current_ev;
2263
2264         rcu_read_lock();
2265         ies = rcu_dereference(bss->pub.ies);
2266         rem = ies->len;
2267         ie = ies->data;
2268
2269         while (rem >= 2) {
2270                 /* invalid data */
2271                 if (ie[1] > rem - 2)
2272                         break;
2273
2274                 switch (ie[0]) {
2275                 case WLAN_EID_SSID:
2276                         memset(&iwe, 0, sizeof(iwe));
2277                         iwe.cmd = SIOCGIWESSID;
2278                         iwe.u.data.length = ie[1];
2279                         iwe.u.data.flags = 1;
2280                         current_ev = iwe_stream_add_point_check(info,
2281                                                                 current_ev,
2282                                                                 end_buf, &iwe,
2283                                                                 (u8 *)ie + 2);
2284                         if (IS_ERR(current_ev))
2285                                 goto unlock;
2286                         break;
2287                 case WLAN_EID_MESH_ID:
2288                         memset(&iwe, 0, sizeof(iwe));
2289                         iwe.cmd = SIOCGIWESSID;
2290                         iwe.u.data.length = ie[1];
2291                         iwe.u.data.flags = 1;
2292                         current_ev = iwe_stream_add_point_check(info,
2293                                                                 current_ev,
2294                                                                 end_buf, &iwe,
2295                                                                 (u8 *)ie + 2);
2296                         if (IS_ERR(current_ev))
2297                                 goto unlock;
2298                         break;
2299                 case WLAN_EID_MESH_CONFIG:
2300                         ismesh = true;
2301                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
2302                                 break;
2303                         cfg = (u8 *)ie + 2;
2304                         memset(&iwe, 0, sizeof(iwe));
2305                         iwe.cmd = IWEVCUSTOM;
2306                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
2307                                 "0x%02X", cfg[0]);
2308                         iwe.u.data.length = strlen(buf);
2309                         current_ev = iwe_stream_add_point_check(info,
2310                                                                 current_ev,
2311                                                                 end_buf,
2312                                                                 &iwe, buf);
2313                         if (IS_ERR(current_ev))
2314                                 goto unlock;
2315                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
2316                                 cfg[1]);
2317                         iwe.u.data.length = strlen(buf);
2318                         current_ev = iwe_stream_add_point_check(info,
2319                                                                 current_ev,
2320                                                                 end_buf,
2321                                                                 &iwe, buf);
2322                         if (IS_ERR(current_ev))
2323                                 goto unlock;
2324                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
2325                                 cfg[2]);
2326                         iwe.u.data.length = strlen(buf);
2327                         current_ev = iwe_stream_add_point_check(info,
2328                                                                 current_ev,
2329                                                                 end_buf,
2330                                                                 &iwe, buf);
2331                         if (IS_ERR(current_ev))
2332                                 goto unlock;
2333                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
2334                         iwe.u.data.length = strlen(buf);
2335                         current_ev = iwe_stream_add_point_check(info,
2336                                                                 current_ev,
2337                                                                 end_buf,
2338                                                                 &iwe, buf);
2339                         if (IS_ERR(current_ev))
2340                                 goto unlock;
2341                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
2342                         iwe.u.data.length = strlen(buf);
2343                         current_ev = iwe_stream_add_point_check(info,
2344                                                                 current_ev,
2345                                                                 end_buf,
2346                                                                 &iwe, buf);
2347                         if (IS_ERR(current_ev))
2348                                 goto unlock;
2349                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
2350                         iwe.u.data.length = strlen(buf);
2351                         current_ev = iwe_stream_add_point_check(info,
2352                                                                 current_ev,
2353                                                                 end_buf,
2354                                                                 &iwe, buf);
2355                         if (IS_ERR(current_ev))
2356                                 goto unlock;
2357                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
2358                         iwe.u.data.length = strlen(buf);
2359                         current_ev = iwe_stream_add_point_check(info,
2360                                                                 current_ev,
2361                                                                 end_buf,
2362                                                                 &iwe, buf);
2363                         if (IS_ERR(current_ev))
2364                                 goto unlock;
2365                         break;
2366                 case WLAN_EID_SUPP_RATES:
2367                 case WLAN_EID_EXT_SUPP_RATES:
2368                         /* display all supported rates in readable format */
2369                         p = current_ev + iwe_stream_lcp_len(info);
2370
2371                         memset(&iwe, 0, sizeof(iwe));
2372                         iwe.cmd = SIOCGIWRATE;
2373                         /* Those two flags are ignored... */
2374                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
2375
2376                         for (i = 0; i < ie[1]; i++) {
2377                                 iwe.u.bitrate.value =
2378                                         ((ie[i + 2] & 0x7f) * 500000);
2379                                 tmp = p;
2380                                 p = iwe_stream_add_value(info, current_ev, p,
2381                                                          end_buf, &iwe,
2382                                                          IW_EV_PARAM_LEN);
2383                                 if (p == tmp) {
2384                                         current_ev = ERR_PTR(-E2BIG);
2385                                         goto unlock;
2386                                 }
2387                         }
2388                         current_ev = p;
2389                         break;
2390                 }
2391                 rem -= ie[1] + 2;
2392                 ie += ie[1] + 2;
2393         }
2394
2395         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
2396             ismesh) {
2397                 memset(&iwe, 0, sizeof(iwe));
2398                 iwe.cmd = SIOCGIWMODE;
2399                 if (ismesh)
2400                         iwe.u.mode = IW_MODE_MESH;
2401                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
2402                         iwe.u.mode = IW_MODE_MASTER;
2403                 else
2404                         iwe.u.mode = IW_MODE_ADHOC;
2405                 current_ev = iwe_stream_add_event_check(info, current_ev,
2406                                                         end_buf, &iwe,
2407                                                         IW_EV_UINT_LEN);
2408                 if (IS_ERR(current_ev))
2409                         goto unlock;
2410         }
2411
2412         memset(&iwe, 0, sizeof(iwe));
2413         iwe.cmd = IWEVCUSTOM;
2414         sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
2415         iwe.u.data.length = strlen(buf);
2416         current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2417                                                 &iwe, buf);
2418         if (IS_ERR(current_ev))
2419                 goto unlock;
2420         memset(&iwe, 0, sizeof(iwe));
2421         iwe.cmd = IWEVCUSTOM;
2422         sprintf(buf, " Last beacon: %ums ago",
2423                 elapsed_jiffies_msecs(bss->ts));
2424         iwe.u.data.length = strlen(buf);
2425         current_ev = iwe_stream_add_point_check(info, current_ev,
2426                                                 end_buf, &iwe, buf);
2427         if (IS_ERR(current_ev))
2428                 goto unlock;
2429
2430         current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
2431
2432  unlock:
2433         rcu_read_unlock();
2434         return current_ev;
2435 }
2436
2437
2438 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
2439                                   struct iw_request_info *info,
2440                                   char *buf, size_t len)
2441 {
2442         char *current_ev = buf;
2443         char *end_buf = buf + len;
2444         struct cfg80211_internal_bss *bss;
2445         int err = 0;
2446
2447         spin_lock_bh(&rdev->bss_lock);
2448         cfg80211_bss_expire(rdev);
2449
2450         list_for_each_entry(bss, &rdev->bss_list, list) {
2451                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
2452                         err = -E2BIG;
2453                         break;
2454                 }
2455                 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
2456                                            current_ev, end_buf);
2457                 if (IS_ERR(current_ev)) {
2458                         err = PTR_ERR(current_ev);
2459                         break;
2460                 }
2461         }
2462         spin_unlock_bh(&rdev->bss_lock);
2463
2464         if (err)
2465                 return err;
2466         return current_ev - buf;
2467 }
2468
2469
2470 int cfg80211_wext_giwscan(struct net_device *dev,
2471                           struct iw_request_info *info,
2472                           struct iw_point *data, char *extra)
2473 {
2474         struct cfg80211_registered_device *rdev;
2475         int res;
2476
2477         if (!netif_running(dev))
2478                 return -ENETDOWN;
2479
2480         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2481
2482         if (IS_ERR(rdev))
2483                 return PTR_ERR(rdev);
2484
2485         if (rdev->scan_req || rdev->scan_msg)
2486                 return -EAGAIN;
2487
2488         res = ieee80211_scan_results(rdev, info, extra, data->length);
2489         data->length = 0;
2490         if (res >= 0) {
2491                 data->length = res;
2492                 res = 0;
2493         }
2494
2495         return res;
2496 }
2497 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
2498 #endif