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1/*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 */
6#include <linux/kernel.h>
7#include <linux/slab.h>
8#include <linux/module.h>
9#include <linux/netdevice.h>
10#include <linux/wireless.h>
11#include <linux/nl80211.h>
12#include <linux/etherdevice.h>
13#include <net/arp.h>
14#include <net/cfg80211.h>
15#include <net/cfg80211-wext.h>
16#include <net/iw_handler.h>
17#include "core.h"
18#include "nl80211.h"
19#include "wext-compat.h"
20#include "rdev-ops.h"
21
22/**
23 * DOC: BSS tree/list structure
24 *
25 * At the top level, the BSS list is kept in both a list in each
26 * registered device (@bss_list) as well as an RB-tree for faster
27 * lookup. In the RB-tree, entries can be looked up using their
28 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
29 * for other BSSes.
30 *
31 * Due to the possibility of hidden SSIDs, there's a second level
32 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
33 * The hidden_list connects all BSSes belonging to a single AP
34 * that has a hidden SSID, and connects beacon and probe response
35 * entries. For a probe response entry for a hidden SSID, the
36 * hidden_beacon_bss pointer points to the BSS struct holding the
37 * beacon's information.
38 *
39 * Reference counting is done for all these references except for
40 * the hidden_list, so that a beacon BSS struct that is otherwise
41 * not referenced has one reference for being on the bss_list and
42 * one for each probe response entry that points to it using the
43 * hidden_beacon_bss pointer. When a BSS struct that has such a
44 * pointer is get/put, the refcount update is also propagated to
45 * the referenced struct, this ensure that it cannot get removed
46 * while somebody is using the probe response version.
47 *
48 * Note that the hidden_beacon_bss pointer never changes, due to
49 * the reference counting. Therefore, no locking is needed for
50 * it.
51 *
52 * Also note that the hidden_beacon_bss pointer is only relevant
53 * if the driver uses something other than the IEs, e.g. private
54 * data stored stored in the BSS struct, since the beacon IEs are
55 * also linked into the probe response struct.
56 */
57
58#define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
59
60static void bss_free(struct cfg80211_internal_bss *bss)
61{
62 struct cfg80211_bss_ies *ies;
63
64 if (WARN_ON(atomic_read(&bss->hold)))
65 return;
66
67 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
68 if (ies && !bss->pub.hidden_beacon_bss)
69 kfree_rcu(ies, rcu_head);
70 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
71 if (ies)
72 kfree_rcu(ies, rcu_head);
73
74 /*
75 * This happens when the module is removed, it doesn't
76 * really matter any more save for completeness
77 */
78 if (!list_empty(&bss->hidden_list))
79 list_del(&bss->hidden_list);
80
81 kfree(bss);
82}
83
84static inline void bss_ref_get(struct cfg80211_registered_device *dev,
85 struct cfg80211_internal_bss *bss)
86{
87 lockdep_assert_held(&dev->bss_lock);
88
89 bss->refcount++;
90 if (bss->pub.hidden_beacon_bss) {
91 bss = container_of(bss->pub.hidden_beacon_bss,
92 struct cfg80211_internal_bss,
93 pub);
94 bss->refcount++;
95 }
96}
97
98static inline void bss_ref_put(struct cfg80211_registered_device *dev,
99 struct cfg80211_internal_bss *bss)
100{
101 lockdep_assert_held(&dev->bss_lock);
102
103 if (bss->pub.hidden_beacon_bss) {
104 struct cfg80211_internal_bss *hbss;
105 hbss = container_of(bss->pub.hidden_beacon_bss,
106 struct cfg80211_internal_bss,
107 pub);
108 hbss->refcount--;
109 if (hbss->refcount == 0)
110 bss_free(hbss);
111 }
112 bss->refcount--;
113 if (bss->refcount == 0)
114 bss_free(bss);
115}
116
117static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
118 struct cfg80211_internal_bss *bss)
119{
120 lockdep_assert_held(&dev->bss_lock);
121
122 if (!list_empty(&bss->hidden_list)) {
123 /*
124 * don't remove the beacon entry if it has
125 * probe responses associated with it
126 */
127 if (!bss->pub.hidden_beacon_bss)
128 return false;
129 /*
130 * if it's a probe response entry break its
131 * link to the other entries in the group
132 */
133 list_del_init(&bss->hidden_list);
134 }
135
136 list_del_init(&bss->list);
137 rb_erase(&bss->rbn, &dev->bss_tree);
138 bss_ref_put(dev, bss);
139 return true;
140}
141
142static void __cfg80211_bss_expire(struct cfg80211_registered_device *dev,
143 unsigned long expire_time)
144{
145 struct cfg80211_internal_bss *bss, *tmp;
146 bool expired = false;
147
148 lockdep_assert_held(&dev->bss_lock);
149
150 list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
151 if (atomic_read(&bss->hold))
152 continue;
153 if (!time_after(expire_time, bss->ts))
154 continue;
155
156 if (__cfg80211_unlink_bss(dev, bss))
157 expired = true;
158 }
159
160 if (expired)
161 dev->bss_generation++;
162}
163
164void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
165 bool send_message)
166{
167 struct cfg80211_scan_request *request;
168 struct wireless_dev *wdev;
169 struct sk_buff *msg;
170#ifdef CONFIG_CFG80211_WEXT
171 union iwreq_data wrqu;
172#endif
173
174 ASSERT_RTNL();
175
176 if (rdev->scan_msg) {
177 nl80211_send_scan_result(rdev, rdev->scan_msg);
178 rdev->scan_msg = NULL;
179 return;
180 }
181
182 request = rdev->scan_req;
183 if (!request)
184 return;
185
186 wdev = request->wdev;
187
188 /*
189 * This must be before sending the other events!
190 * Otherwise, wpa_supplicant gets completely confused with
191 * wext events.
192 */
193 if (wdev->netdev)
194 cfg80211_sme_scan_done(wdev->netdev);
195
196 if (!request->aborted &&
197 request->flags & NL80211_SCAN_FLAG_FLUSH) {
198 /* flush entries from previous scans */
199 spin_lock_bh(&rdev->bss_lock);
200 __cfg80211_bss_expire(rdev, request->scan_start);
201 spin_unlock_bh(&rdev->bss_lock);
202 }
203
204 msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
205
206#ifdef CONFIG_CFG80211_WEXT
207 if (wdev->netdev && !request->aborted) {
208 memset(&wrqu, 0, sizeof(wrqu));
209
210 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
211 }
212#endif
213
214 if (wdev->netdev)
215 dev_put(wdev->netdev);
216
217 rdev->scan_req = NULL;
218 kfree(request);
219
220 if (!send_message)
221 rdev->scan_msg = msg;
222 else
223 nl80211_send_scan_result(rdev, msg);
224}
225
226void __cfg80211_scan_done(struct work_struct *wk)
227{
228 struct cfg80211_registered_device *rdev;
229
230 rdev = container_of(wk, struct cfg80211_registered_device,
231 scan_done_wk);
232
233 rtnl_lock();
234 ___cfg80211_scan_done(rdev, true);
235 rtnl_unlock();
236}
237
238void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
239{
240 trace_cfg80211_scan_done(request, aborted);
241 WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
242
243 request->aborted = aborted;
244 request->notified = true;
245 queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
246}
247EXPORT_SYMBOL(cfg80211_scan_done);
248
249void __cfg80211_sched_scan_results(struct work_struct *wk)
250{
251 struct cfg80211_registered_device *rdev;
252 struct cfg80211_sched_scan_request *request;
253
254 rdev = container_of(wk, struct cfg80211_registered_device,
255 sched_scan_results_wk);
256
257 rtnl_lock();
258
259 request = rdev->sched_scan_req;
260
261 /* we don't have sched_scan_req anymore if the scan is stopping */
262 if (request) {
263 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
264 /* flush entries from previous scans */
265 spin_lock_bh(&rdev->bss_lock);
266 __cfg80211_bss_expire(rdev, request->scan_start);
267 spin_unlock_bh(&rdev->bss_lock);
268 request->scan_start =
269 jiffies + msecs_to_jiffies(request->interval);
270 }
271 nl80211_send_sched_scan_results(rdev, request->dev);
272 }
273
274 rtnl_unlock();
275}
276
277void cfg80211_sched_scan_results(struct wiphy *wiphy)
278{
279 trace_cfg80211_sched_scan_results(wiphy);
280 /* ignore if we're not scanning */
281 if (wiphy_to_dev(wiphy)->sched_scan_req)
282 queue_work(cfg80211_wq,
283 &wiphy_to_dev(wiphy)->sched_scan_results_wk);
284}
285EXPORT_SYMBOL(cfg80211_sched_scan_results);
286
287void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
288{
289 struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
290
291 ASSERT_RTNL();
292
293 trace_cfg80211_sched_scan_stopped(wiphy);
294
295 __cfg80211_stop_sched_scan(rdev, true);
296}
297EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
298
299void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
300{
301 rtnl_lock();
302 cfg80211_sched_scan_stopped_rtnl(wiphy);
303 rtnl_unlock();
304}
305EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
306
307int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
308 bool driver_initiated)
309{
310 struct net_device *dev;
311
312 ASSERT_RTNL();
313
314 if (!rdev->sched_scan_req)
315 return -ENOENT;
316
317 dev = rdev->sched_scan_req->dev;
318
319 if (!driver_initiated) {
320 int err = rdev_sched_scan_stop(rdev, dev);
321 if (err)
322 return err;
323 }
324
325 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
326
327 kfree(rdev->sched_scan_req);
328 rdev->sched_scan_req = NULL;
329
330 return 0;
331}
332
333void cfg80211_bss_age(struct cfg80211_registered_device *dev,
334 unsigned long age_secs)
335{
336 struct cfg80211_internal_bss *bss;
337 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
338
339 spin_lock_bh(&dev->bss_lock);
340 list_for_each_entry(bss, &dev->bss_list, list)
341 bss->ts -= age_jiffies;
342 spin_unlock_bh(&dev->bss_lock);
343}
344
345void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
346{
347 __cfg80211_bss_expire(dev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
348}
349
350const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
351{
352 while (len > 2 && ies[0] != eid) {
353 len -= ies[1] + 2;
354 ies += ies[1] + 2;
355 }
356 if (len < 2)
357 return NULL;
358 if (len < 2 + ies[1])
359 return NULL;
360 return ies;
361}
362EXPORT_SYMBOL(cfg80211_find_ie);
363
364const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
365 const u8 *ies, int len)
366{
367 struct ieee80211_vendor_ie *ie;
368 const u8 *pos = ies, *end = ies + len;
369 int ie_oui;
370
371 while (pos < end) {
372 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
373 end - pos);
374 if (!pos)
375 return NULL;
376
377 ie = (struct ieee80211_vendor_ie *)pos;
378
379 /* make sure we can access ie->len */
380 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
381
382 if (ie->len < sizeof(*ie))
383 goto cont;
384
385 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
386 if (ie_oui == oui && ie->oui_type == oui_type)
387 return pos;
388cont:
389 pos += 2 + ie->len;
390 }
391 return NULL;
392}
393EXPORT_SYMBOL(cfg80211_find_vendor_ie);
394
395static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
396 const u8 *ssid, size_t ssid_len)
397{
398 const struct cfg80211_bss_ies *ies;
399 const u8 *ssidie;
400
401 if (bssid && !ether_addr_equal(a->bssid, bssid))
402 return false;
403
404 if (!ssid)
405 return true;
406
407 ies = rcu_access_pointer(a->ies);
408 if (!ies)
409 return false;
410 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
411 if (!ssidie)
412 return false;
413 if (ssidie[1] != ssid_len)
414 return false;
415 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
416}
417
418/**
419 * enum bss_compare_mode - BSS compare mode
420 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
421 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
422 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
423 */
424enum bss_compare_mode {
425 BSS_CMP_REGULAR,
426 BSS_CMP_HIDE_ZLEN,
427 BSS_CMP_HIDE_NUL,
428};
429
430static int cmp_bss(struct cfg80211_bss *a,
431 struct cfg80211_bss *b,
432 enum bss_compare_mode mode)
433{
434 const struct cfg80211_bss_ies *a_ies, *b_ies;
435 const u8 *ie1 = NULL;
436 const u8 *ie2 = NULL;
437 int i, r;
438
439 if (a->channel != b->channel)
440 return b->channel->center_freq - a->channel->center_freq;
441
442 a_ies = rcu_access_pointer(a->ies);
443 if (!a_ies)
444 return -1;
445 b_ies = rcu_access_pointer(b->ies);
446 if (!b_ies)
447 return 1;
448
449 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
450 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
451 a_ies->data, a_ies->len);
452 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
453 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
454 b_ies->data, b_ies->len);
455 if (ie1 && ie2) {
456 int mesh_id_cmp;
457
458 if (ie1[1] == ie2[1])
459 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
460 else
461 mesh_id_cmp = ie2[1] - ie1[1];
462
463 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
464 a_ies->data, a_ies->len);
465 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
466 b_ies->data, b_ies->len);
467 if (ie1 && ie2) {
468 if (mesh_id_cmp)
469 return mesh_id_cmp;
470 if (ie1[1] != ie2[1])
471 return ie2[1] - ie1[1];
472 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
473 }
474 }
475
476 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
477 if (r)
478 return r;
479
480 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
481 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
482
483 if (!ie1 && !ie2)
484 return 0;
485
486 /*
487 * Note that with "hide_ssid", the function returns a match if
488 * the already-present BSS ("b") is a hidden SSID beacon for
489 * the new BSS ("a").
490 */
491
492 /* sort missing IE before (left of) present IE */
493 if (!ie1)
494 return -1;
495 if (!ie2)
496 return 1;
497
498 switch (mode) {
499 case BSS_CMP_HIDE_ZLEN:
500 /*
501 * In ZLEN mode we assume the BSS entry we're
502 * looking for has a zero-length SSID. So if
503 * the one we're looking at right now has that,
504 * return 0. Otherwise, return the difference
505 * in length, but since we're looking for the
506 * 0-length it's really equivalent to returning
507 * the length of the one we're looking at.
508 *
509 * No content comparison is needed as we assume
510 * the content length is zero.
511 */
512 return ie2[1];
513 case BSS_CMP_REGULAR:
514 default:
515 /* sort by length first, then by contents */
516 if (ie1[1] != ie2[1])
517 return ie2[1] - ie1[1];
518 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
519 case BSS_CMP_HIDE_NUL:
520 if (ie1[1] != ie2[1])
521 return ie2[1] - ie1[1];
522 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
523 for (i = 0; i < ie2[1]; i++)
524 if (ie2[i + 2])
525 return -1;
526 return 0;
527 }
528}
529
530/* Returned bss is reference counted and must be cleaned up appropriately. */
531struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
532 struct ieee80211_channel *channel,
533 const u8 *bssid,
534 const u8 *ssid, size_t ssid_len,
535 u16 capa_mask, u16 capa_val)
536{
537 struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
538 struct cfg80211_internal_bss *bss, *res = NULL;
539 unsigned long now = jiffies;
540
541 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
542 capa_val);
543
544 spin_lock_bh(&dev->bss_lock);
545
546 list_for_each_entry(bss, &dev->bss_list, list) {
547 if ((bss->pub.capability & capa_mask) != capa_val)
548 continue;
549 if (channel && bss->pub.channel != channel)
550 continue;
551 /* Don't get expired BSS structs */
552 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
553 !atomic_read(&bss->hold))
554 continue;
555 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
556 res = bss;
557 bss_ref_get(dev, res);
558 break;
559 }
560 }
561
562 spin_unlock_bh(&dev->bss_lock);
563 if (!res)
564 return NULL;
565 trace_cfg80211_return_bss(&res->pub);
566 return &res->pub;
567}
568EXPORT_SYMBOL(cfg80211_get_bss);
569
570static void rb_insert_bss(struct cfg80211_registered_device *dev,
571 struct cfg80211_internal_bss *bss)
572{
573 struct rb_node **p = &dev->bss_tree.rb_node;
574 struct rb_node *parent = NULL;
575 struct cfg80211_internal_bss *tbss;
576 int cmp;
577
578 while (*p) {
579 parent = *p;
580 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
581
582 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
583
584 if (WARN_ON(!cmp)) {
585 /* will sort of leak this BSS */
586 return;
587 }
588
589 if (cmp < 0)
590 p = &(*p)->rb_left;
591 else
592 p = &(*p)->rb_right;
593 }
594
595 rb_link_node(&bss->rbn, parent, p);
596 rb_insert_color(&bss->rbn, &dev->bss_tree);
597}
598
599static struct cfg80211_internal_bss *
600rb_find_bss(struct cfg80211_registered_device *dev,
601 struct cfg80211_internal_bss *res,
602 enum bss_compare_mode mode)
603{
604 struct rb_node *n = dev->bss_tree.rb_node;
605 struct cfg80211_internal_bss *bss;
606 int r;
607
608 while (n) {
609 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
610 r = cmp_bss(&res->pub, &bss->pub, mode);
611
612 if (r == 0)
613 return bss;
614 else if (r < 0)
615 n = n->rb_left;
616 else
617 n = n->rb_right;
618 }
619
620 return NULL;
621}
622
623static bool cfg80211_combine_bsses(struct cfg80211_registered_device *dev,
624 struct cfg80211_internal_bss *new)
625{
626 const struct cfg80211_bss_ies *ies;
627 struct cfg80211_internal_bss *bss;
628 const u8 *ie;
629 int i, ssidlen;
630 u8 fold = 0;
631
632 ies = rcu_access_pointer(new->pub.beacon_ies);
633 if (WARN_ON(!ies))
634 return false;
635
636 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
637 if (!ie) {
638 /* nothing to do */
639 return true;
640 }
641
642 ssidlen = ie[1];
643 for (i = 0; i < ssidlen; i++)
644 fold |= ie[2 + i];
645
646 if (fold) {
647 /* not a hidden SSID */
648 return true;
649 }
650
651 /* This is the bad part ... */
652
653 list_for_each_entry(bss, &dev->bss_list, list) {
654 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
655 continue;
656 if (bss->pub.channel != new->pub.channel)
657 continue;
658 if (bss->pub.scan_width != new->pub.scan_width)
659 continue;
660 if (rcu_access_pointer(bss->pub.beacon_ies))
661 continue;
662 ies = rcu_access_pointer(bss->pub.ies);
663 if (!ies)
664 continue;
665 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
666 if (!ie)
667 continue;
668 if (ssidlen && ie[1] != ssidlen)
669 continue;
670 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
671 continue;
672 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
673 list_del(&bss->hidden_list);
674 /* combine them */
675 list_add(&bss->hidden_list, &new->hidden_list);
676 bss->pub.hidden_beacon_bss = &new->pub;
677 new->refcount += bss->refcount;
678 rcu_assign_pointer(bss->pub.beacon_ies,
679 new->pub.beacon_ies);
680 }
681
682 return true;
683}
684
685/* Returned bss is reference counted and must be cleaned up appropriately. */
686static struct cfg80211_internal_bss *
687cfg80211_bss_update(struct cfg80211_registered_device *dev,
688 struct cfg80211_internal_bss *tmp,
689 bool signal_valid)
690{
691 struct cfg80211_internal_bss *found = NULL;
692
693 if (WARN_ON(!tmp->pub.channel))
694 return NULL;
695
696 tmp->ts = jiffies;
697
698 spin_lock_bh(&dev->bss_lock);
699
700 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
701 spin_unlock_bh(&dev->bss_lock);
702 return NULL;
703 }
704
705 found = rb_find_bss(dev, tmp, BSS_CMP_REGULAR);
706
707 if (found) {
708 /* Update IEs */
709 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
710 const struct cfg80211_bss_ies *old;
711
712 old = rcu_access_pointer(found->pub.proberesp_ies);
713
714 rcu_assign_pointer(found->pub.proberesp_ies,
715 tmp->pub.proberesp_ies);
716 /* Override possible earlier Beacon frame IEs */
717 rcu_assign_pointer(found->pub.ies,
718 tmp->pub.proberesp_ies);
719 if (old)
720 kfree_rcu((struct cfg80211_bss_ies *)old,
721 rcu_head);
722 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
723 const struct cfg80211_bss_ies *old;
724 struct cfg80211_internal_bss *bss;
725
726 if (found->pub.hidden_beacon_bss &&
727 !list_empty(&found->hidden_list)) {
728 const struct cfg80211_bss_ies *f;
729
730 /*
731 * The found BSS struct is one of the probe
732 * response members of a group, but we're
733 * receiving a beacon (beacon_ies in the tmp
734 * bss is used). This can only mean that the
735 * AP changed its beacon from not having an
736 * SSID to showing it, which is confusing so
737 * drop this information.
738 */
739
740 f = rcu_access_pointer(tmp->pub.beacon_ies);
741 kfree_rcu((struct cfg80211_bss_ies *)f,
742 rcu_head);
743 goto drop;
744 }
745
746 old = rcu_access_pointer(found->pub.beacon_ies);
747
748 rcu_assign_pointer(found->pub.beacon_ies,
749 tmp->pub.beacon_ies);
750
751 /* Override IEs if they were from a beacon before */
752 if (old == rcu_access_pointer(found->pub.ies))
753 rcu_assign_pointer(found->pub.ies,
754 tmp->pub.beacon_ies);
755
756 /* Assign beacon IEs to all sub entries */
757 list_for_each_entry(bss, &found->hidden_list,
758 hidden_list) {
759 const struct cfg80211_bss_ies *ies;
760
761 ies = rcu_access_pointer(bss->pub.beacon_ies);
762 WARN_ON(ies != old);
763
764 rcu_assign_pointer(bss->pub.beacon_ies,
765 tmp->pub.beacon_ies);
766 }
767
768 if (old)
769 kfree_rcu((struct cfg80211_bss_ies *)old,
770 rcu_head);
771 }
772
773 found->pub.beacon_interval = tmp->pub.beacon_interval;
774 /*
775 * don't update the signal if beacon was heard on
776 * adjacent channel.
777 */
778 if (signal_valid)
779 found->pub.signal = tmp->pub.signal;
780 found->pub.capability = tmp->pub.capability;
781 found->ts = tmp->ts;
782 } else {
783 struct cfg80211_internal_bss *new;
784 struct cfg80211_internal_bss *hidden;
785 struct cfg80211_bss_ies *ies;
786
787 /*
788 * create a copy -- the "res" variable that is passed in
789 * is allocated on the stack since it's not needed in the
790 * more common case of an update
791 */
792 new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size,
793 GFP_ATOMIC);
794 if (!new) {
795 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
796 if (ies)
797 kfree_rcu(ies, rcu_head);
798 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
799 if (ies)
800 kfree_rcu(ies, rcu_head);
801 goto drop;
802 }
803 memcpy(new, tmp, sizeof(*new));
804 new->refcount = 1;
805 INIT_LIST_HEAD(&new->hidden_list);
806
807 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
808 hidden = rb_find_bss(dev, tmp, BSS_CMP_HIDE_ZLEN);
809 if (!hidden)
810 hidden = rb_find_bss(dev, tmp,
811 BSS_CMP_HIDE_NUL);
812 if (hidden) {
813 new->pub.hidden_beacon_bss = &hidden->pub;
814 list_add(&new->hidden_list,
815 &hidden->hidden_list);
816 hidden->refcount++;
817 rcu_assign_pointer(new->pub.beacon_ies,
818 hidden->pub.beacon_ies);
819 }
820 } else {
821 /*
822 * Ok so we found a beacon, and don't have an entry. If
823 * it's a beacon with hidden SSID, we might be in for an
824 * expensive search for any probe responses that should
825 * be grouped with this beacon for updates ...
826 */
827 if (!cfg80211_combine_bsses(dev, new)) {
828 kfree(new);
829 goto drop;
830 }
831 }
832
833 list_add_tail(&new->list, &dev->bss_list);
834 rb_insert_bss(dev, new);
835 found = new;
836 }
837
838 dev->bss_generation++;
839 bss_ref_get(dev, found);
840 spin_unlock_bh(&dev->bss_lock);
841
842 return found;
843 drop:
844 spin_unlock_bh(&dev->bss_lock);
845 return NULL;
846}
847
848static struct ieee80211_channel *
849cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
850 struct ieee80211_channel *channel)
851{
852 const u8 *tmp;
853 u32 freq;
854 int channel_number = -1;
855
856 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
857 if (tmp && tmp[1] == 1) {
858 channel_number = tmp[2];
859 } else {
860 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
861 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
862 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
863
864 channel_number = htop->primary_chan;
865 }
866 }
867
868 if (channel_number < 0)
869 return channel;
870
871 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
872 channel = ieee80211_get_channel(wiphy, freq);
873 if (!channel)
874 return NULL;
875 if (channel->flags & IEEE80211_CHAN_DISABLED)
876 return NULL;
877 return channel;
878}
879
880/* Returned bss is reference counted and must be cleaned up appropriately. */
881struct cfg80211_bss*
882cfg80211_inform_bss_width(struct wiphy *wiphy,
883 struct ieee80211_channel *rx_channel,
884 enum nl80211_bss_scan_width scan_width,
885 const u8 *bssid, u64 tsf, u16 capability,
886 u16 beacon_interval, const u8 *ie, size_t ielen,
887 s32 signal, gfp_t gfp)
888{
889 struct cfg80211_bss_ies *ies;
890 struct ieee80211_channel *channel;
891 struct cfg80211_internal_bss tmp = {}, *res;
892
893 if (WARN_ON(!wiphy))
894 return NULL;
895
896 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
897 (signal < 0 || signal > 100)))
898 return NULL;
899
900 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, rx_channel);
901 if (!channel)
902 return NULL;
903
904 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
905 tmp.pub.channel = channel;
906 tmp.pub.scan_width = scan_width;
907 tmp.pub.signal = signal;
908 tmp.pub.beacon_interval = beacon_interval;
909 tmp.pub.capability = capability;
910 /*
911 * Since we do not know here whether the IEs are from a Beacon or Probe
912 * Response frame, we need to pick one of the options and only use it
913 * with the driver that does not provide the full Beacon/Probe Response
914 * frame. Use Beacon frame pointer to avoid indicating that this should
915 * override the IEs pointer should we have received an earlier
916 * indication of Probe Response data.
917 */
918 ies = kmalloc(sizeof(*ies) + ielen, gfp);
919 if (!ies)
920 return NULL;
921 ies->len = ielen;
922 ies->tsf = tsf;
923 memcpy(ies->data, ie, ielen);
924
925 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
926 rcu_assign_pointer(tmp.pub.ies, ies);
927
928 res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp,
929 rx_channel == channel);
930 if (!res)
931 return NULL;
932
933 if (res->pub.capability & WLAN_CAPABILITY_ESS)
934 regulatory_hint_found_beacon(wiphy, channel, gfp);
935
936 trace_cfg80211_return_bss(&res->pub);
937 /* cfg80211_bss_update gives us a referenced result */
938 return &res->pub;
939}
940EXPORT_SYMBOL(cfg80211_inform_bss_width);
941
942/* Returned bss is reference counted and must be cleaned up appropriately. */
943struct cfg80211_bss *
944cfg80211_inform_bss_width_frame(struct wiphy *wiphy,
945 struct ieee80211_channel *rx_channel,
946 enum nl80211_bss_scan_width scan_width,
947 struct ieee80211_mgmt *mgmt, size_t len,
948 s32 signal, gfp_t gfp)
949{
950 struct cfg80211_internal_bss tmp = {}, *res;
951 struct cfg80211_bss_ies *ies;
952 struct ieee80211_channel *channel;
953 size_t ielen = len - offsetof(struct ieee80211_mgmt,
954 u.probe_resp.variable);
955
956 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
957 offsetof(struct ieee80211_mgmt, u.beacon.variable));
958
959 trace_cfg80211_inform_bss_width_frame(wiphy, rx_channel, scan_width, mgmt,
960 len, signal);
961
962 if (WARN_ON(!mgmt))
963 return NULL;
964
965 if (WARN_ON(!wiphy))
966 return NULL;
967
968 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
969 (signal < 0 || signal > 100)))
970 return NULL;
971
972 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
973 return NULL;
974
975 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
976 ielen, rx_channel);
977 if (!channel)
978 return NULL;
979
980 ies = kmalloc(sizeof(*ies) + ielen, gfp);
981 if (!ies)
982 return NULL;
983 ies->len = ielen;
984 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
985 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
986
987 if (ieee80211_is_probe_resp(mgmt->frame_control))
988 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
989 else
990 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
991 rcu_assign_pointer(tmp.pub.ies, ies);
992
993 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
994 tmp.pub.channel = channel;
995 tmp.pub.scan_width = scan_width;
996 tmp.pub.signal = signal;
997 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
998 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
999
1000 res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp,
1001 rx_channel == channel);
1002 if (!res)
1003 return NULL;
1004
1005 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1006 regulatory_hint_found_beacon(wiphy, channel, gfp);
1007
1008 trace_cfg80211_return_bss(&res->pub);
1009 /* cfg80211_bss_update gives us a referenced result */
1010 return &res->pub;
1011}
1012EXPORT_SYMBOL(cfg80211_inform_bss_width_frame);
1013
1014void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1015{
1016 struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1017 struct cfg80211_internal_bss *bss;
1018
1019 if (!pub)
1020 return;
1021
1022 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1023
1024 spin_lock_bh(&dev->bss_lock);
1025 bss_ref_get(dev, bss);
1026 spin_unlock_bh(&dev->bss_lock);
1027}
1028EXPORT_SYMBOL(cfg80211_ref_bss);
1029
1030void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1031{
1032 struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1033 struct cfg80211_internal_bss *bss;
1034
1035 if (!pub)
1036 return;
1037
1038 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1039
1040 spin_lock_bh(&dev->bss_lock);
1041 bss_ref_put(dev, bss);
1042 spin_unlock_bh(&dev->bss_lock);
1043}
1044EXPORT_SYMBOL(cfg80211_put_bss);
1045
1046void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1047{
1048 struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1049 struct cfg80211_internal_bss *bss;
1050
1051 if (WARN_ON(!pub))
1052 return;
1053
1054 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1055
1056 spin_lock_bh(&dev->bss_lock);
1057 if (!list_empty(&bss->list)) {
1058 if (__cfg80211_unlink_bss(dev, bss))
1059 dev->bss_generation++;
1060 }
1061 spin_unlock_bh(&dev->bss_lock);
1062}
1063EXPORT_SYMBOL(cfg80211_unlink_bss);
1064
1065#ifdef CONFIG_CFG80211_WEXT
1066static struct cfg80211_registered_device *
1067cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1068{
1069 struct cfg80211_registered_device *rdev;
1070 struct net_device *dev;
1071
1072 ASSERT_RTNL();
1073
1074 dev = dev_get_by_index(net, ifindex);
1075 if (!dev)
1076 return ERR_PTR(-ENODEV);
1077 if (dev->ieee80211_ptr)
1078 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
1079 else
1080 rdev = ERR_PTR(-ENODEV);
1081 dev_put(dev);
1082 return rdev;
1083}
1084
1085int cfg80211_wext_siwscan(struct net_device *dev,
1086 struct iw_request_info *info,
1087 union iwreq_data *wrqu, char *extra)
1088{
1089 struct cfg80211_registered_device *rdev;
1090 struct wiphy *wiphy;
1091 struct iw_scan_req *wreq = NULL;
1092 struct cfg80211_scan_request *creq = NULL;
1093 int i, err, n_channels = 0;
1094 enum ieee80211_band band;
1095
1096 if (!netif_running(dev))
1097 return -ENETDOWN;
1098
1099 if (wrqu->data.length == sizeof(struct iw_scan_req))
1100 wreq = (struct iw_scan_req *)extra;
1101
1102 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1103
1104 if (IS_ERR(rdev))
1105 return PTR_ERR(rdev);
1106
1107 if (rdev->scan_req || rdev->scan_msg) {
1108 err = -EBUSY;
1109 goto out;
1110 }
1111
1112 wiphy = &rdev->wiphy;
1113
1114 /* Determine number of channels, needed to allocate creq */
1115 if (wreq && wreq->num_channels)
1116 n_channels = wreq->num_channels;
1117 else
1118 n_channels = ieee80211_get_num_supported_channels(wiphy);
1119
1120 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1121 n_channels * sizeof(void *),
1122 GFP_ATOMIC);
1123 if (!creq) {
1124 err = -ENOMEM;
1125 goto out;
1126 }
1127
1128 creq->wiphy = wiphy;
1129 creq->wdev = dev->ieee80211_ptr;
1130 /* SSIDs come after channels */
1131 creq->ssids = (void *)&creq->channels[n_channels];
1132 creq->n_channels = n_channels;
1133 creq->n_ssids = 1;
1134 creq->scan_start = jiffies;
1135
1136 /* translate "Scan on frequencies" request */
1137 i = 0;
1138 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1139 int j;
1140
1141 if (!wiphy->bands[band])
1142 continue;
1143
1144 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1145 /* ignore disabled channels */
1146 if (wiphy->bands[band]->channels[j].flags &
1147 IEEE80211_CHAN_DISABLED)
1148 continue;
1149
1150 /* If we have a wireless request structure and the
1151 * wireless request specifies frequencies, then search
1152 * for the matching hardware channel.
1153 */
1154 if (wreq && wreq->num_channels) {
1155 int k;
1156 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1157 for (k = 0; k < wreq->num_channels; k++) {
1158 int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
1159 if (wext_freq == wiphy_freq)
1160 goto wext_freq_found;
1161 }
1162 goto wext_freq_not_found;
1163 }
1164
1165 wext_freq_found:
1166 creq->channels[i] = &wiphy->bands[band]->channels[j];
1167 i++;
1168 wext_freq_not_found: ;
1169 }
1170 }
1171 /* No channels found? */
1172 if (!i) {
1173 err = -EINVAL;
1174 goto out;
1175 }
1176
1177 /* Set real number of channels specified in creq->channels[] */
1178 creq->n_channels = i;
1179
1180 /* translate "Scan for SSID" request */
1181 if (wreq) {
1182 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1183 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1184 err = -EINVAL;
1185 goto out;
1186 }
1187 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1188 creq->ssids[0].ssid_len = wreq->essid_len;
1189 }
1190 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1191 creq->n_ssids = 0;
1192 }
1193
1194 for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1195 if (wiphy->bands[i])
1196 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1197
1198 rdev->scan_req = creq;
1199 err = rdev_scan(rdev, creq);
1200 if (err) {
1201 rdev->scan_req = NULL;
1202 /* creq will be freed below */
1203 } else {
1204 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1205 /* creq now owned by driver */
1206 creq = NULL;
1207 dev_hold(dev);
1208 }
1209 out:
1210 kfree(creq);
1211 return err;
1212}
1213EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1214
1215static void ieee80211_scan_add_ies(struct iw_request_info *info,
1216 const struct cfg80211_bss_ies *ies,
1217 char **current_ev, char *end_buf)
1218{
1219 const u8 *pos, *end, *next;
1220 struct iw_event iwe;
1221
1222 if (!ies)
1223 return;
1224
1225 /*
1226 * If needed, fragment the IEs buffer (at IE boundaries) into short
1227 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1228 */
1229 pos = ies->data;
1230 end = pos + ies->len;
1231
1232 while (end - pos > IW_GENERIC_IE_MAX) {
1233 next = pos + 2 + pos[1];
1234 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1235 next = next + 2 + next[1];
1236
1237 memset(&iwe, 0, sizeof(iwe));
1238 iwe.cmd = IWEVGENIE;
1239 iwe.u.data.length = next - pos;
1240 *current_ev = iwe_stream_add_point(info, *current_ev,
1241 end_buf, &iwe,
1242 (void *)pos);
1243
1244 pos = next;
1245 }
1246
1247 if (end > pos) {
1248 memset(&iwe, 0, sizeof(iwe));
1249 iwe.cmd = IWEVGENIE;
1250 iwe.u.data.length = end - pos;
1251 *current_ev = iwe_stream_add_point(info, *current_ev,
1252 end_buf, &iwe,
1253 (void *)pos);
1254 }
1255}
1256
1257static char *
1258ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1259 struct cfg80211_internal_bss *bss, char *current_ev,
1260 char *end_buf)
1261{
1262 const struct cfg80211_bss_ies *ies;
1263 struct iw_event iwe;
1264 const u8 *ie;
1265 u8 *buf, *cfg, *p;
1266 int rem, i, sig;
1267 bool ismesh = false;
1268
1269 memset(&iwe, 0, sizeof(iwe));
1270 iwe.cmd = SIOCGIWAP;
1271 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1272 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1273 current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1274 IW_EV_ADDR_LEN);
1275
1276 memset(&iwe, 0, sizeof(iwe));
1277 iwe.cmd = SIOCGIWFREQ;
1278 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1279 iwe.u.freq.e = 0;
1280 current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1281 IW_EV_FREQ_LEN);
1282
1283 memset(&iwe, 0, sizeof(iwe));
1284 iwe.cmd = SIOCGIWFREQ;
1285 iwe.u.freq.m = bss->pub.channel->center_freq;
1286 iwe.u.freq.e = 6;
1287 current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1288 IW_EV_FREQ_LEN);
1289
1290 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1291 memset(&iwe, 0, sizeof(iwe));
1292 iwe.cmd = IWEVQUAL;
1293 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1294 IW_QUAL_NOISE_INVALID |
1295 IW_QUAL_QUAL_UPDATED;
1296 switch (wiphy->signal_type) {
1297 case CFG80211_SIGNAL_TYPE_MBM:
1298 sig = bss->pub.signal / 100;
1299 iwe.u.qual.level = sig;
1300 iwe.u.qual.updated |= IW_QUAL_DBM;
1301 if (sig < -110) /* rather bad */
1302 sig = -110;
1303 else if (sig > -40) /* perfect */
1304 sig = -40;
1305 /* will give a range of 0 .. 70 */
1306 iwe.u.qual.qual = sig + 110;
1307 break;
1308 case CFG80211_SIGNAL_TYPE_UNSPEC:
1309 iwe.u.qual.level = bss->pub.signal;
1310 /* will give range 0 .. 100 */
1311 iwe.u.qual.qual = bss->pub.signal;
1312 break;
1313 default:
1314 /* not reached */
1315 break;
1316 }
1317 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1318 &iwe, IW_EV_QUAL_LEN);
1319 }
1320
1321 memset(&iwe, 0, sizeof(iwe));
1322 iwe.cmd = SIOCGIWENCODE;
1323 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1324 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1325 else
1326 iwe.u.data.flags = IW_ENCODE_DISABLED;
1327 iwe.u.data.length = 0;
1328 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1329 &iwe, "");
1330
1331 rcu_read_lock();
1332 ies = rcu_dereference(bss->pub.ies);
1333 rem = ies->len;
1334 ie = ies->data;
1335
1336 while (rem >= 2) {
1337 /* invalid data */
1338 if (ie[1] > rem - 2)
1339 break;
1340
1341 switch (ie[0]) {
1342 case WLAN_EID_SSID:
1343 memset(&iwe, 0, sizeof(iwe));
1344 iwe.cmd = SIOCGIWESSID;
1345 iwe.u.data.length = ie[1];
1346 iwe.u.data.flags = 1;
1347 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1348 &iwe, (u8 *)ie + 2);
1349 break;
1350 case WLAN_EID_MESH_ID:
1351 memset(&iwe, 0, sizeof(iwe));
1352 iwe.cmd = SIOCGIWESSID;
1353 iwe.u.data.length = ie[1];
1354 iwe.u.data.flags = 1;
1355 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1356 &iwe, (u8 *)ie + 2);
1357 break;
1358 case WLAN_EID_MESH_CONFIG:
1359 ismesh = true;
1360 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1361 break;
1362 buf = kmalloc(50, GFP_ATOMIC);
1363 if (!buf)
1364 break;
1365 cfg = (u8 *)ie + 2;
1366 memset(&iwe, 0, sizeof(iwe));
1367 iwe.cmd = IWEVCUSTOM;
1368 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1369 "0x%02X", cfg[0]);
1370 iwe.u.data.length = strlen(buf);
1371 current_ev = iwe_stream_add_point(info, current_ev,
1372 end_buf,
1373 &iwe, buf);
1374 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1375 cfg[1]);
1376 iwe.u.data.length = strlen(buf);
1377 current_ev = iwe_stream_add_point(info, current_ev,
1378 end_buf,
1379 &iwe, buf);
1380 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1381 cfg[2]);
1382 iwe.u.data.length = strlen(buf);
1383 current_ev = iwe_stream_add_point(info, current_ev,
1384 end_buf,
1385 &iwe, buf);
1386 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1387 iwe.u.data.length = strlen(buf);
1388 current_ev = iwe_stream_add_point(info, current_ev,
1389 end_buf,
1390 &iwe, buf);
1391 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1392 iwe.u.data.length = strlen(buf);
1393 current_ev = iwe_stream_add_point(info, current_ev,
1394 end_buf,
1395 &iwe, buf);
1396 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1397 iwe.u.data.length = strlen(buf);
1398 current_ev = iwe_stream_add_point(info, current_ev,
1399 end_buf,
1400 &iwe, buf);
1401 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1402 iwe.u.data.length = strlen(buf);
1403 current_ev = iwe_stream_add_point(info, current_ev,
1404 end_buf,
1405 &iwe, buf);
1406 kfree(buf);
1407 break;
1408 case WLAN_EID_SUPP_RATES:
1409 case WLAN_EID_EXT_SUPP_RATES:
1410 /* display all supported rates in readable format */
1411 p = current_ev + iwe_stream_lcp_len(info);
1412
1413 memset(&iwe, 0, sizeof(iwe));
1414 iwe.cmd = SIOCGIWRATE;
1415 /* Those two flags are ignored... */
1416 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1417
1418 for (i = 0; i < ie[1]; i++) {
1419 iwe.u.bitrate.value =
1420 ((ie[i + 2] & 0x7f) * 500000);
1421 p = iwe_stream_add_value(info, current_ev, p,
1422 end_buf, &iwe, IW_EV_PARAM_LEN);
1423 }
1424 current_ev = p;
1425 break;
1426 }
1427 rem -= ie[1] + 2;
1428 ie += ie[1] + 2;
1429 }
1430
1431 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1432 ismesh) {
1433 memset(&iwe, 0, sizeof(iwe));
1434 iwe.cmd = SIOCGIWMODE;
1435 if (ismesh)
1436 iwe.u.mode = IW_MODE_MESH;
1437 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1438 iwe.u.mode = IW_MODE_MASTER;
1439 else
1440 iwe.u.mode = IW_MODE_ADHOC;
1441 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1442 &iwe, IW_EV_UINT_LEN);
1443 }
1444
1445 buf = kmalloc(31, GFP_ATOMIC);
1446 if (buf) {
1447 memset(&iwe, 0, sizeof(iwe));
1448 iwe.cmd = IWEVCUSTOM;
1449 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1450 iwe.u.data.length = strlen(buf);
1451 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1452 &iwe, buf);
1453 memset(&iwe, 0, sizeof(iwe));
1454 iwe.cmd = IWEVCUSTOM;
1455 sprintf(buf, " Last beacon: %ums ago",
1456 elapsed_jiffies_msecs(bss->ts));
1457 iwe.u.data.length = strlen(buf);
1458 current_ev = iwe_stream_add_point(info, current_ev,
1459 end_buf, &iwe, buf);
1460 kfree(buf);
1461 }
1462
1463 ieee80211_scan_add_ies(info, ies, ¤t_ev, end_buf);
1464 rcu_read_unlock();
1465
1466 return current_ev;
1467}
1468
1469
1470static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1471 struct iw_request_info *info,
1472 char *buf, size_t len)
1473{
1474 char *current_ev = buf;
1475 char *end_buf = buf + len;
1476 struct cfg80211_internal_bss *bss;
1477
1478 spin_lock_bh(&dev->bss_lock);
1479 cfg80211_bss_expire(dev);
1480
1481 list_for_each_entry(bss, &dev->bss_list, list) {
1482 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1483 spin_unlock_bh(&dev->bss_lock);
1484 return -E2BIG;
1485 }
1486 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1487 current_ev, end_buf);
1488 }
1489 spin_unlock_bh(&dev->bss_lock);
1490 return current_ev - buf;
1491}
1492
1493
1494int cfg80211_wext_giwscan(struct net_device *dev,
1495 struct iw_request_info *info,
1496 struct iw_point *data, char *extra)
1497{
1498 struct cfg80211_registered_device *rdev;
1499 int res;
1500
1501 if (!netif_running(dev))
1502 return -ENETDOWN;
1503
1504 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1505
1506 if (IS_ERR(rdev))
1507 return PTR_ERR(rdev);
1508
1509 if (rdev->scan_req || rdev->scan_msg)
1510 return -EAGAIN;
1511
1512 res = ieee80211_scan_results(rdev, info, extra, data->length);
1513 data->length = 0;
1514 if (res >= 0) {
1515 data->length = res;
1516 res = 0;
1517 }
1518
1519 return res;
1520}
1521EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1522#endif
1/*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 * Copyright 2013-2014 Intel Mobile Communications GmbH
6 */
7#include <linux/kernel.h>
8#include <linux/slab.h>
9#include <linux/module.h>
10#include <linux/netdevice.h>
11#include <linux/wireless.h>
12#include <linux/nl80211.h>
13#include <linux/etherdevice.h>
14#include <net/arp.h>
15#include <net/cfg80211.h>
16#include <net/cfg80211-wext.h>
17#include <net/iw_handler.h>
18#include "core.h"
19#include "nl80211.h"
20#include "wext-compat.h"
21#include "rdev-ops.h"
22
23/**
24 * DOC: BSS tree/list structure
25 *
26 * At the top level, the BSS list is kept in both a list in each
27 * registered device (@bss_list) as well as an RB-tree for faster
28 * lookup. In the RB-tree, entries can be looked up using their
29 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
30 * for other BSSes.
31 *
32 * Due to the possibility of hidden SSIDs, there's a second level
33 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
34 * The hidden_list connects all BSSes belonging to a single AP
35 * that has a hidden SSID, and connects beacon and probe response
36 * entries. For a probe response entry for a hidden SSID, the
37 * hidden_beacon_bss pointer points to the BSS struct holding the
38 * beacon's information.
39 *
40 * Reference counting is done for all these references except for
41 * the hidden_list, so that a beacon BSS struct that is otherwise
42 * not referenced has one reference for being on the bss_list and
43 * one for each probe response entry that points to it using the
44 * hidden_beacon_bss pointer. When a BSS struct that has such a
45 * pointer is get/put, the refcount update is also propagated to
46 * the referenced struct, this ensure that it cannot get removed
47 * while somebody is using the probe response version.
48 *
49 * Note that the hidden_beacon_bss pointer never changes, due to
50 * the reference counting. Therefore, no locking is needed for
51 * it.
52 *
53 * Also note that the hidden_beacon_bss pointer is only relevant
54 * if the driver uses something other than the IEs, e.g. private
55 * data stored stored in the BSS struct, since the beacon IEs are
56 * also linked into the probe response struct.
57 */
58
59#define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
60
61static void bss_free(struct cfg80211_internal_bss *bss)
62{
63 struct cfg80211_bss_ies *ies;
64
65 if (WARN_ON(atomic_read(&bss->hold)))
66 return;
67
68 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
69 if (ies && !bss->pub.hidden_beacon_bss)
70 kfree_rcu(ies, rcu_head);
71 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
72 if (ies)
73 kfree_rcu(ies, rcu_head);
74
75 /*
76 * This happens when the module is removed, it doesn't
77 * really matter any more save for completeness
78 */
79 if (!list_empty(&bss->hidden_list))
80 list_del(&bss->hidden_list);
81
82 kfree(bss);
83}
84
85static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
86 struct cfg80211_internal_bss *bss)
87{
88 lockdep_assert_held(&rdev->bss_lock);
89
90 bss->refcount++;
91 if (bss->pub.hidden_beacon_bss) {
92 bss = container_of(bss->pub.hidden_beacon_bss,
93 struct cfg80211_internal_bss,
94 pub);
95 bss->refcount++;
96 }
97}
98
99static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
100 struct cfg80211_internal_bss *bss)
101{
102 lockdep_assert_held(&rdev->bss_lock);
103
104 if (bss->pub.hidden_beacon_bss) {
105 struct cfg80211_internal_bss *hbss;
106 hbss = container_of(bss->pub.hidden_beacon_bss,
107 struct cfg80211_internal_bss,
108 pub);
109 hbss->refcount--;
110 if (hbss->refcount == 0)
111 bss_free(hbss);
112 }
113 bss->refcount--;
114 if (bss->refcount == 0)
115 bss_free(bss);
116}
117
118static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
119 struct cfg80211_internal_bss *bss)
120{
121 lockdep_assert_held(&rdev->bss_lock);
122
123 if (!list_empty(&bss->hidden_list)) {
124 /*
125 * don't remove the beacon entry if it has
126 * probe responses associated with it
127 */
128 if (!bss->pub.hidden_beacon_bss)
129 return false;
130 /*
131 * if it's a probe response entry break its
132 * link to the other entries in the group
133 */
134 list_del_init(&bss->hidden_list);
135 }
136
137 list_del_init(&bss->list);
138 rb_erase(&bss->rbn, &rdev->bss_tree);
139 bss_ref_put(rdev, bss);
140 return true;
141}
142
143static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
144 unsigned long expire_time)
145{
146 struct cfg80211_internal_bss *bss, *tmp;
147 bool expired = false;
148
149 lockdep_assert_held(&rdev->bss_lock);
150
151 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
152 if (atomic_read(&bss->hold))
153 continue;
154 if (!time_after(expire_time, bss->ts))
155 continue;
156
157 if (__cfg80211_unlink_bss(rdev, bss))
158 expired = true;
159 }
160
161 if (expired)
162 rdev->bss_generation++;
163}
164
165void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
166 bool send_message)
167{
168 struct cfg80211_scan_request *request;
169 struct wireless_dev *wdev;
170 struct sk_buff *msg;
171#ifdef CONFIG_CFG80211_WEXT
172 union iwreq_data wrqu;
173#endif
174
175 ASSERT_RTNL();
176
177 if (rdev->scan_msg) {
178 nl80211_send_scan_result(rdev, rdev->scan_msg);
179 rdev->scan_msg = NULL;
180 return;
181 }
182
183 request = rdev->scan_req;
184 if (!request)
185 return;
186
187 wdev = request->wdev;
188
189 /*
190 * This must be before sending the other events!
191 * Otherwise, wpa_supplicant gets completely confused with
192 * wext events.
193 */
194 if (wdev->netdev)
195 cfg80211_sme_scan_done(wdev->netdev);
196
197 if (!request->aborted &&
198 request->flags & NL80211_SCAN_FLAG_FLUSH) {
199 /* flush entries from previous scans */
200 spin_lock_bh(&rdev->bss_lock);
201 __cfg80211_bss_expire(rdev, request->scan_start);
202 spin_unlock_bh(&rdev->bss_lock);
203 }
204
205 msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
206
207#ifdef CONFIG_CFG80211_WEXT
208 if (wdev->netdev && !request->aborted) {
209 memset(&wrqu, 0, sizeof(wrqu));
210
211 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
212 }
213#endif
214
215 if (wdev->netdev)
216 dev_put(wdev->netdev);
217
218 rdev->scan_req = NULL;
219 kfree(request);
220
221 if (!send_message)
222 rdev->scan_msg = msg;
223 else
224 nl80211_send_scan_result(rdev, msg);
225}
226
227void __cfg80211_scan_done(struct work_struct *wk)
228{
229 struct cfg80211_registered_device *rdev;
230
231 rdev = container_of(wk, struct cfg80211_registered_device,
232 scan_done_wk);
233
234 rtnl_lock();
235 ___cfg80211_scan_done(rdev, true);
236 rtnl_unlock();
237}
238
239void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
240{
241 trace_cfg80211_scan_done(request, aborted);
242 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
243
244 request->aborted = aborted;
245 request->notified = true;
246 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
247}
248EXPORT_SYMBOL(cfg80211_scan_done);
249
250void __cfg80211_sched_scan_results(struct work_struct *wk)
251{
252 struct cfg80211_registered_device *rdev;
253 struct cfg80211_sched_scan_request *request;
254
255 rdev = container_of(wk, struct cfg80211_registered_device,
256 sched_scan_results_wk);
257
258 rtnl_lock();
259
260 request = rtnl_dereference(rdev->sched_scan_req);
261
262 /* we don't have sched_scan_req anymore if the scan is stopping */
263 if (request) {
264 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
265 /* flush entries from previous scans */
266 spin_lock_bh(&rdev->bss_lock);
267 __cfg80211_bss_expire(rdev, request->scan_start);
268 spin_unlock_bh(&rdev->bss_lock);
269 request->scan_start = jiffies;
270 }
271 nl80211_send_sched_scan_results(rdev, request->dev);
272 }
273
274 rtnl_unlock();
275}
276
277void cfg80211_sched_scan_results(struct wiphy *wiphy)
278{
279 trace_cfg80211_sched_scan_results(wiphy);
280 /* ignore if we're not scanning */
281
282 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
283 queue_work(cfg80211_wq,
284 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
285}
286EXPORT_SYMBOL(cfg80211_sched_scan_results);
287
288void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
289{
290 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
291
292 ASSERT_RTNL();
293
294 trace_cfg80211_sched_scan_stopped(wiphy);
295
296 __cfg80211_stop_sched_scan(rdev, true);
297}
298EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
299
300void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
301{
302 rtnl_lock();
303 cfg80211_sched_scan_stopped_rtnl(wiphy);
304 rtnl_unlock();
305}
306EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
307
308int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
309 bool driver_initiated)
310{
311 struct cfg80211_sched_scan_request *sched_scan_req;
312 struct net_device *dev;
313
314 ASSERT_RTNL();
315
316 if (!rdev->sched_scan_req)
317 return -ENOENT;
318
319 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
320 dev = sched_scan_req->dev;
321
322 if (!driver_initiated) {
323 int err = rdev_sched_scan_stop(rdev, dev);
324 if (err)
325 return err;
326 }
327
328 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
329
330 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
331 kfree_rcu(sched_scan_req, rcu_head);
332
333 return 0;
334}
335
336void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
337 unsigned long age_secs)
338{
339 struct cfg80211_internal_bss *bss;
340 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
341
342 spin_lock_bh(&rdev->bss_lock);
343 list_for_each_entry(bss, &rdev->bss_list, list)
344 bss->ts -= age_jiffies;
345 spin_unlock_bh(&rdev->bss_lock);
346}
347
348void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
349{
350 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
351}
352
353const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
354{
355 while (len > 2 && ies[0] != eid) {
356 len -= ies[1] + 2;
357 ies += ies[1] + 2;
358 }
359 if (len < 2)
360 return NULL;
361 if (len < 2 + ies[1])
362 return NULL;
363 return ies;
364}
365EXPORT_SYMBOL(cfg80211_find_ie);
366
367const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
368 const u8 *ies, int len)
369{
370 struct ieee80211_vendor_ie *ie;
371 const u8 *pos = ies, *end = ies + len;
372 int ie_oui;
373
374 while (pos < end) {
375 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
376 end - pos);
377 if (!pos)
378 return NULL;
379
380 ie = (struct ieee80211_vendor_ie *)pos;
381
382 /* make sure we can access ie->len */
383 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
384
385 if (ie->len < sizeof(*ie))
386 goto cont;
387
388 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
389 if (ie_oui == oui && ie->oui_type == oui_type)
390 return pos;
391cont:
392 pos += 2 + ie->len;
393 }
394 return NULL;
395}
396EXPORT_SYMBOL(cfg80211_find_vendor_ie);
397
398static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
399 const u8 *ssid, size_t ssid_len)
400{
401 const struct cfg80211_bss_ies *ies;
402 const u8 *ssidie;
403
404 if (bssid && !ether_addr_equal(a->bssid, bssid))
405 return false;
406
407 if (!ssid)
408 return true;
409
410 ies = rcu_access_pointer(a->ies);
411 if (!ies)
412 return false;
413 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
414 if (!ssidie)
415 return false;
416 if (ssidie[1] != ssid_len)
417 return false;
418 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
419}
420
421/**
422 * enum bss_compare_mode - BSS compare mode
423 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
424 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
425 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
426 */
427enum bss_compare_mode {
428 BSS_CMP_REGULAR,
429 BSS_CMP_HIDE_ZLEN,
430 BSS_CMP_HIDE_NUL,
431};
432
433static int cmp_bss(struct cfg80211_bss *a,
434 struct cfg80211_bss *b,
435 enum bss_compare_mode mode)
436{
437 const struct cfg80211_bss_ies *a_ies, *b_ies;
438 const u8 *ie1 = NULL;
439 const u8 *ie2 = NULL;
440 int i, r;
441
442 if (a->channel != b->channel)
443 return b->channel->center_freq - a->channel->center_freq;
444
445 a_ies = rcu_access_pointer(a->ies);
446 if (!a_ies)
447 return -1;
448 b_ies = rcu_access_pointer(b->ies);
449 if (!b_ies)
450 return 1;
451
452 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
453 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
454 a_ies->data, a_ies->len);
455 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
456 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
457 b_ies->data, b_ies->len);
458 if (ie1 && ie2) {
459 int mesh_id_cmp;
460
461 if (ie1[1] == ie2[1])
462 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
463 else
464 mesh_id_cmp = ie2[1] - ie1[1];
465
466 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
467 a_ies->data, a_ies->len);
468 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
469 b_ies->data, b_ies->len);
470 if (ie1 && ie2) {
471 if (mesh_id_cmp)
472 return mesh_id_cmp;
473 if (ie1[1] != ie2[1])
474 return ie2[1] - ie1[1];
475 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
476 }
477 }
478
479 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
480 if (r)
481 return r;
482
483 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
484 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
485
486 if (!ie1 && !ie2)
487 return 0;
488
489 /*
490 * Note that with "hide_ssid", the function returns a match if
491 * the already-present BSS ("b") is a hidden SSID beacon for
492 * the new BSS ("a").
493 */
494
495 /* sort missing IE before (left of) present IE */
496 if (!ie1)
497 return -1;
498 if (!ie2)
499 return 1;
500
501 switch (mode) {
502 case BSS_CMP_HIDE_ZLEN:
503 /*
504 * In ZLEN mode we assume the BSS entry we're
505 * looking for has a zero-length SSID. So if
506 * the one we're looking at right now has that,
507 * return 0. Otherwise, return the difference
508 * in length, but since we're looking for the
509 * 0-length it's really equivalent to returning
510 * the length of the one we're looking at.
511 *
512 * No content comparison is needed as we assume
513 * the content length is zero.
514 */
515 return ie2[1];
516 case BSS_CMP_REGULAR:
517 default:
518 /* sort by length first, then by contents */
519 if (ie1[1] != ie2[1])
520 return ie2[1] - ie1[1];
521 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
522 case BSS_CMP_HIDE_NUL:
523 if (ie1[1] != ie2[1])
524 return ie2[1] - ie1[1];
525 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
526 for (i = 0; i < ie2[1]; i++)
527 if (ie2[i + 2])
528 return -1;
529 return 0;
530 }
531}
532
533static bool cfg80211_bss_type_match(u16 capability,
534 enum ieee80211_band band,
535 enum ieee80211_bss_type bss_type)
536{
537 bool ret = true;
538 u16 mask, val;
539
540 if (bss_type == IEEE80211_BSS_TYPE_ANY)
541 return ret;
542
543 if (band == IEEE80211_BAND_60GHZ) {
544 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
545 switch (bss_type) {
546 case IEEE80211_BSS_TYPE_ESS:
547 val = WLAN_CAPABILITY_DMG_TYPE_AP;
548 break;
549 case IEEE80211_BSS_TYPE_PBSS:
550 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
551 break;
552 case IEEE80211_BSS_TYPE_IBSS:
553 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
554 break;
555 default:
556 return false;
557 }
558 } else {
559 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
560 switch (bss_type) {
561 case IEEE80211_BSS_TYPE_ESS:
562 val = WLAN_CAPABILITY_ESS;
563 break;
564 case IEEE80211_BSS_TYPE_IBSS:
565 val = WLAN_CAPABILITY_IBSS;
566 break;
567 case IEEE80211_BSS_TYPE_MBSS:
568 val = 0;
569 break;
570 default:
571 return false;
572 }
573 }
574
575 ret = ((capability & mask) == val);
576 return ret;
577}
578
579/* Returned bss is reference counted and must be cleaned up appropriately. */
580struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
581 struct ieee80211_channel *channel,
582 const u8 *bssid,
583 const u8 *ssid, size_t ssid_len,
584 enum ieee80211_bss_type bss_type,
585 enum ieee80211_privacy privacy)
586{
587 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
588 struct cfg80211_internal_bss *bss, *res = NULL;
589 unsigned long now = jiffies;
590 int bss_privacy;
591
592 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
593 privacy);
594
595 spin_lock_bh(&rdev->bss_lock);
596
597 list_for_each_entry(bss, &rdev->bss_list, list) {
598 if (!cfg80211_bss_type_match(bss->pub.capability,
599 bss->pub.channel->band, bss_type))
600 continue;
601
602 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
603 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
604 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
605 continue;
606 if (channel && bss->pub.channel != channel)
607 continue;
608 if (!is_valid_ether_addr(bss->pub.bssid))
609 continue;
610 /* Don't get expired BSS structs */
611 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
612 !atomic_read(&bss->hold))
613 continue;
614 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
615 res = bss;
616 bss_ref_get(rdev, res);
617 break;
618 }
619 }
620
621 spin_unlock_bh(&rdev->bss_lock);
622 if (!res)
623 return NULL;
624 trace_cfg80211_return_bss(&res->pub);
625 return &res->pub;
626}
627EXPORT_SYMBOL(cfg80211_get_bss);
628
629static void rb_insert_bss(struct cfg80211_registered_device *rdev,
630 struct cfg80211_internal_bss *bss)
631{
632 struct rb_node **p = &rdev->bss_tree.rb_node;
633 struct rb_node *parent = NULL;
634 struct cfg80211_internal_bss *tbss;
635 int cmp;
636
637 while (*p) {
638 parent = *p;
639 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
640
641 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
642
643 if (WARN_ON(!cmp)) {
644 /* will sort of leak this BSS */
645 return;
646 }
647
648 if (cmp < 0)
649 p = &(*p)->rb_left;
650 else
651 p = &(*p)->rb_right;
652 }
653
654 rb_link_node(&bss->rbn, parent, p);
655 rb_insert_color(&bss->rbn, &rdev->bss_tree);
656}
657
658static struct cfg80211_internal_bss *
659rb_find_bss(struct cfg80211_registered_device *rdev,
660 struct cfg80211_internal_bss *res,
661 enum bss_compare_mode mode)
662{
663 struct rb_node *n = rdev->bss_tree.rb_node;
664 struct cfg80211_internal_bss *bss;
665 int r;
666
667 while (n) {
668 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
669 r = cmp_bss(&res->pub, &bss->pub, mode);
670
671 if (r == 0)
672 return bss;
673 else if (r < 0)
674 n = n->rb_left;
675 else
676 n = n->rb_right;
677 }
678
679 return NULL;
680}
681
682static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
683 struct cfg80211_internal_bss *new)
684{
685 const struct cfg80211_bss_ies *ies;
686 struct cfg80211_internal_bss *bss;
687 const u8 *ie;
688 int i, ssidlen;
689 u8 fold = 0;
690
691 ies = rcu_access_pointer(new->pub.beacon_ies);
692 if (WARN_ON(!ies))
693 return false;
694
695 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
696 if (!ie) {
697 /* nothing to do */
698 return true;
699 }
700
701 ssidlen = ie[1];
702 for (i = 0; i < ssidlen; i++)
703 fold |= ie[2 + i];
704
705 if (fold) {
706 /* not a hidden SSID */
707 return true;
708 }
709
710 /* This is the bad part ... */
711
712 list_for_each_entry(bss, &rdev->bss_list, list) {
713 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
714 continue;
715 if (bss->pub.channel != new->pub.channel)
716 continue;
717 if (bss->pub.scan_width != new->pub.scan_width)
718 continue;
719 if (rcu_access_pointer(bss->pub.beacon_ies))
720 continue;
721 ies = rcu_access_pointer(bss->pub.ies);
722 if (!ies)
723 continue;
724 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
725 if (!ie)
726 continue;
727 if (ssidlen && ie[1] != ssidlen)
728 continue;
729 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
730 continue;
731 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
732 list_del(&bss->hidden_list);
733 /* combine them */
734 list_add(&bss->hidden_list, &new->hidden_list);
735 bss->pub.hidden_beacon_bss = &new->pub;
736 new->refcount += bss->refcount;
737 rcu_assign_pointer(bss->pub.beacon_ies,
738 new->pub.beacon_ies);
739 }
740
741 return true;
742}
743
744/* Returned bss is reference counted and must be cleaned up appropriately. */
745static struct cfg80211_internal_bss *
746cfg80211_bss_update(struct cfg80211_registered_device *rdev,
747 struct cfg80211_internal_bss *tmp,
748 bool signal_valid)
749{
750 struct cfg80211_internal_bss *found = NULL;
751
752 if (WARN_ON(!tmp->pub.channel))
753 return NULL;
754
755 tmp->ts = jiffies;
756
757 spin_lock_bh(&rdev->bss_lock);
758
759 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
760 spin_unlock_bh(&rdev->bss_lock);
761 return NULL;
762 }
763
764 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
765
766 if (found) {
767 /* Update IEs */
768 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
769 const struct cfg80211_bss_ies *old;
770
771 old = rcu_access_pointer(found->pub.proberesp_ies);
772
773 rcu_assign_pointer(found->pub.proberesp_ies,
774 tmp->pub.proberesp_ies);
775 /* Override possible earlier Beacon frame IEs */
776 rcu_assign_pointer(found->pub.ies,
777 tmp->pub.proberesp_ies);
778 if (old)
779 kfree_rcu((struct cfg80211_bss_ies *)old,
780 rcu_head);
781 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
782 const struct cfg80211_bss_ies *old;
783 struct cfg80211_internal_bss *bss;
784
785 if (found->pub.hidden_beacon_bss &&
786 !list_empty(&found->hidden_list)) {
787 const struct cfg80211_bss_ies *f;
788
789 /*
790 * The found BSS struct is one of the probe
791 * response members of a group, but we're
792 * receiving a beacon (beacon_ies in the tmp
793 * bss is used). This can only mean that the
794 * AP changed its beacon from not having an
795 * SSID to showing it, which is confusing so
796 * drop this information.
797 */
798
799 f = rcu_access_pointer(tmp->pub.beacon_ies);
800 kfree_rcu((struct cfg80211_bss_ies *)f,
801 rcu_head);
802 goto drop;
803 }
804
805 old = rcu_access_pointer(found->pub.beacon_ies);
806
807 rcu_assign_pointer(found->pub.beacon_ies,
808 tmp->pub.beacon_ies);
809
810 /* Override IEs if they were from a beacon before */
811 if (old == rcu_access_pointer(found->pub.ies))
812 rcu_assign_pointer(found->pub.ies,
813 tmp->pub.beacon_ies);
814
815 /* Assign beacon IEs to all sub entries */
816 list_for_each_entry(bss, &found->hidden_list,
817 hidden_list) {
818 const struct cfg80211_bss_ies *ies;
819
820 ies = rcu_access_pointer(bss->pub.beacon_ies);
821 WARN_ON(ies != old);
822
823 rcu_assign_pointer(bss->pub.beacon_ies,
824 tmp->pub.beacon_ies);
825 }
826
827 if (old)
828 kfree_rcu((struct cfg80211_bss_ies *)old,
829 rcu_head);
830 }
831
832 found->pub.beacon_interval = tmp->pub.beacon_interval;
833 /*
834 * don't update the signal if beacon was heard on
835 * adjacent channel.
836 */
837 if (signal_valid)
838 found->pub.signal = tmp->pub.signal;
839 found->pub.capability = tmp->pub.capability;
840 found->ts = tmp->ts;
841 found->ts_boottime = tmp->ts_boottime;
842 } else {
843 struct cfg80211_internal_bss *new;
844 struct cfg80211_internal_bss *hidden;
845 struct cfg80211_bss_ies *ies;
846
847 /*
848 * create a copy -- the "res" variable that is passed in
849 * is allocated on the stack since it's not needed in the
850 * more common case of an update
851 */
852 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
853 GFP_ATOMIC);
854 if (!new) {
855 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
856 if (ies)
857 kfree_rcu(ies, rcu_head);
858 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
859 if (ies)
860 kfree_rcu(ies, rcu_head);
861 goto drop;
862 }
863 memcpy(new, tmp, sizeof(*new));
864 new->refcount = 1;
865 INIT_LIST_HEAD(&new->hidden_list);
866
867 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
868 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
869 if (!hidden)
870 hidden = rb_find_bss(rdev, tmp,
871 BSS_CMP_HIDE_NUL);
872 if (hidden) {
873 new->pub.hidden_beacon_bss = &hidden->pub;
874 list_add(&new->hidden_list,
875 &hidden->hidden_list);
876 hidden->refcount++;
877 rcu_assign_pointer(new->pub.beacon_ies,
878 hidden->pub.beacon_ies);
879 }
880 } else {
881 /*
882 * Ok so we found a beacon, and don't have an entry. If
883 * it's a beacon with hidden SSID, we might be in for an
884 * expensive search for any probe responses that should
885 * be grouped with this beacon for updates ...
886 */
887 if (!cfg80211_combine_bsses(rdev, new)) {
888 kfree(new);
889 goto drop;
890 }
891 }
892
893 list_add_tail(&new->list, &rdev->bss_list);
894 rb_insert_bss(rdev, new);
895 found = new;
896 }
897
898 rdev->bss_generation++;
899 bss_ref_get(rdev, found);
900 spin_unlock_bh(&rdev->bss_lock);
901
902 return found;
903 drop:
904 spin_unlock_bh(&rdev->bss_lock);
905 return NULL;
906}
907
908static struct ieee80211_channel *
909cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
910 struct ieee80211_channel *channel)
911{
912 const u8 *tmp;
913 u32 freq;
914 int channel_number = -1;
915
916 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
917 if (tmp && tmp[1] == 1) {
918 channel_number = tmp[2];
919 } else {
920 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
921 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
922 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
923
924 channel_number = htop->primary_chan;
925 }
926 }
927
928 if (channel_number < 0)
929 return channel;
930
931 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
932 channel = ieee80211_get_channel(wiphy, freq);
933 if (!channel)
934 return NULL;
935 if (channel->flags & IEEE80211_CHAN_DISABLED)
936 return NULL;
937 return channel;
938}
939
940/* Returned bss is reference counted and must be cleaned up appropriately. */
941struct cfg80211_bss *
942cfg80211_inform_bss_data(struct wiphy *wiphy,
943 struct cfg80211_inform_bss *data,
944 enum cfg80211_bss_frame_type ftype,
945 const u8 *bssid, u64 tsf, u16 capability,
946 u16 beacon_interval, const u8 *ie, size_t ielen,
947 gfp_t gfp)
948{
949 struct cfg80211_bss_ies *ies;
950 struct ieee80211_channel *channel;
951 struct cfg80211_internal_bss tmp = {}, *res;
952 int bss_type;
953 bool signal_valid;
954
955 if (WARN_ON(!wiphy))
956 return NULL;
957
958 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
959 (data->signal < 0 || data->signal > 100)))
960 return NULL;
961
962 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan);
963 if (!channel)
964 return NULL;
965
966 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
967 tmp.pub.channel = channel;
968 tmp.pub.scan_width = data->scan_width;
969 tmp.pub.signal = data->signal;
970 tmp.pub.beacon_interval = beacon_interval;
971 tmp.pub.capability = capability;
972 tmp.ts_boottime = data->boottime_ns;
973
974 /*
975 * If we do not know here whether the IEs are from a Beacon or Probe
976 * Response frame, we need to pick one of the options and only use it
977 * with the driver that does not provide the full Beacon/Probe Response
978 * frame. Use Beacon frame pointer to avoid indicating that this should
979 * override the IEs pointer should we have received an earlier
980 * indication of Probe Response data.
981 */
982 ies = kzalloc(sizeof(*ies) + ielen, gfp);
983 if (!ies)
984 return NULL;
985 ies->len = ielen;
986 ies->tsf = tsf;
987 ies->from_beacon = false;
988 memcpy(ies->data, ie, ielen);
989
990 switch (ftype) {
991 case CFG80211_BSS_FTYPE_BEACON:
992 ies->from_beacon = true;
993 /* fall through to assign */
994 case CFG80211_BSS_FTYPE_UNKNOWN:
995 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
996 break;
997 case CFG80211_BSS_FTYPE_PRESP:
998 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
999 break;
1000 }
1001 rcu_assign_pointer(tmp.pub.ies, ies);
1002
1003 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1004 wiphy->max_adj_channel_rssi_comp;
1005 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1006 if (!res)
1007 return NULL;
1008
1009 if (channel->band == IEEE80211_BAND_60GHZ) {
1010 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1011 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1012 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1013 regulatory_hint_found_beacon(wiphy, channel, gfp);
1014 } else {
1015 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1016 regulatory_hint_found_beacon(wiphy, channel, gfp);
1017 }
1018
1019 trace_cfg80211_return_bss(&res->pub);
1020 /* cfg80211_bss_update gives us a referenced result */
1021 return &res->pub;
1022}
1023EXPORT_SYMBOL(cfg80211_inform_bss_data);
1024
1025/* cfg80211_inform_bss_width_frame helper */
1026struct cfg80211_bss *
1027cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1028 struct cfg80211_inform_bss *data,
1029 struct ieee80211_mgmt *mgmt, size_t len,
1030 gfp_t gfp)
1031
1032{
1033 struct cfg80211_internal_bss tmp = {}, *res;
1034 struct cfg80211_bss_ies *ies;
1035 struct ieee80211_channel *channel;
1036 bool signal_valid;
1037 size_t ielen = len - offsetof(struct ieee80211_mgmt,
1038 u.probe_resp.variable);
1039 int bss_type;
1040
1041 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1042 offsetof(struct ieee80211_mgmt, u.beacon.variable));
1043
1044 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1045
1046 if (WARN_ON(!mgmt))
1047 return NULL;
1048
1049 if (WARN_ON(!wiphy))
1050 return NULL;
1051
1052 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1053 (data->signal < 0 || data->signal > 100)))
1054 return NULL;
1055
1056 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1057 return NULL;
1058
1059 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1060 ielen, data->chan);
1061 if (!channel)
1062 return NULL;
1063
1064 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1065 if (!ies)
1066 return NULL;
1067 ies->len = ielen;
1068 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1069 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1070 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1071
1072 if (ieee80211_is_probe_resp(mgmt->frame_control))
1073 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1074 else
1075 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1076 rcu_assign_pointer(tmp.pub.ies, ies);
1077
1078 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1079 tmp.pub.channel = channel;
1080 tmp.pub.scan_width = data->scan_width;
1081 tmp.pub.signal = data->signal;
1082 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1083 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1084 tmp.ts_boottime = data->boottime_ns;
1085
1086 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1087 wiphy->max_adj_channel_rssi_comp;
1088 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1089 if (!res)
1090 return NULL;
1091
1092 if (channel->band == IEEE80211_BAND_60GHZ) {
1093 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1094 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1095 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1096 regulatory_hint_found_beacon(wiphy, channel, gfp);
1097 } else {
1098 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1099 regulatory_hint_found_beacon(wiphy, channel, gfp);
1100 }
1101
1102 trace_cfg80211_return_bss(&res->pub);
1103 /* cfg80211_bss_update gives us a referenced result */
1104 return &res->pub;
1105}
1106EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1107
1108void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1109{
1110 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1111 struct cfg80211_internal_bss *bss;
1112
1113 if (!pub)
1114 return;
1115
1116 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1117
1118 spin_lock_bh(&rdev->bss_lock);
1119 bss_ref_get(rdev, bss);
1120 spin_unlock_bh(&rdev->bss_lock);
1121}
1122EXPORT_SYMBOL(cfg80211_ref_bss);
1123
1124void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1125{
1126 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1127 struct cfg80211_internal_bss *bss;
1128
1129 if (!pub)
1130 return;
1131
1132 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1133
1134 spin_lock_bh(&rdev->bss_lock);
1135 bss_ref_put(rdev, bss);
1136 spin_unlock_bh(&rdev->bss_lock);
1137}
1138EXPORT_SYMBOL(cfg80211_put_bss);
1139
1140void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1141{
1142 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1143 struct cfg80211_internal_bss *bss;
1144
1145 if (WARN_ON(!pub))
1146 return;
1147
1148 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1149
1150 spin_lock_bh(&rdev->bss_lock);
1151 if (!list_empty(&bss->list)) {
1152 if (__cfg80211_unlink_bss(rdev, bss))
1153 rdev->bss_generation++;
1154 }
1155 spin_unlock_bh(&rdev->bss_lock);
1156}
1157EXPORT_SYMBOL(cfg80211_unlink_bss);
1158
1159#ifdef CONFIG_CFG80211_WEXT
1160static struct cfg80211_registered_device *
1161cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1162{
1163 struct cfg80211_registered_device *rdev;
1164 struct net_device *dev;
1165
1166 ASSERT_RTNL();
1167
1168 dev = dev_get_by_index(net, ifindex);
1169 if (!dev)
1170 return ERR_PTR(-ENODEV);
1171 if (dev->ieee80211_ptr)
1172 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1173 else
1174 rdev = ERR_PTR(-ENODEV);
1175 dev_put(dev);
1176 return rdev;
1177}
1178
1179int cfg80211_wext_siwscan(struct net_device *dev,
1180 struct iw_request_info *info,
1181 union iwreq_data *wrqu, char *extra)
1182{
1183 struct cfg80211_registered_device *rdev;
1184 struct wiphy *wiphy;
1185 struct iw_scan_req *wreq = NULL;
1186 struct cfg80211_scan_request *creq = NULL;
1187 int i, err, n_channels = 0;
1188 enum ieee80211_band band;
1189
1190 if (!netif_running(dev))
1191 return -ENETDOWN;
1192
1193 if (wrqu->data.length == sizeof(struct iw_scan_req))
1194 wreq = (struct iw_scan_req *)extra;
1195
1196 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1197
1198 if (IS_ERR(rdev))
1199 return PTR_ERR(rdev);
1200
1201 if (rdev->scan_req || rdev->scan_msg) {
1202 err = -EBUSY;
1203 goto out;
1204 }
1205
1206 wiphy = &rdev->wiphy;
1207
1208 /* Determine number of channels, needed to allocate creq */
1209 if (wreq && wreq->num_channels)
1210 n_channels = wreq->num_channels;
1211 else
1212 n_channels = ieee80211_get_num_supported_channels(wiphy);
1213
1214 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1215 n_channels * sizeof(void *),
1216 GFP_ATOMIC);
1217 if (!creq) {
1218 err = -ENOMEM;
1219 goto out;
1220 }
1221
1222 creq->wiphy = wiphy;
1223 creq->wdev = dev->ieee80211_ptr;
1224 /* SSIDs come after channels */
1225 creq->ssids = (void *)&creq->channels[n_channels];
1226 creq->n_channels = n_channels;
1227 creq->n_ssids = 1;
1228 creq->scan_start = jiffies;
1229
1230 /* translate "Scan on frequencies" request */
1231 i = 0;
1232 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1233 int j;
1234
1235 if (!wiphy->bands[band])
1236 continue;
1237
1238 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1239 /* ignore disabled channels */
1240 if (wiphy->bands[band]->channels[j].flags &
1241 IEEE80211_CHAN_DISABLED)
1242 continue;
1243
1244 /* If we have a wireless request structure and the
1245 * wireless request specifies frequencies, then search
1246 * for the matching hardware channel.
1247 */
1248 if (wreq && wreq->num_channels) {
1249 int k;
1250 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1251 for (k = 0; k < wreq->num_channels; k++) {
1252 struct iw_freq *freq =
1253 &wreq->channel_list[k];
1254 int wext_freq =
1255 cfg80211_wext_freq(freq);
1256
1257 if (wext_freq == wiphy_freq)
1258 goto wext_freq_found;
1259 }
1260 goto wext_freq_not_found;
1261 }
1262
1263 wext_freq_found:
1264 creq->channels[i] = &wiphy->bands[band]->channels[j];
1265 i++;
1266 wext_freq_not_found: ;
1267 }
1268 }
1269 /* No channels found? */
1270 if (!i) {
1271 err = -EINVAL;
1272 goto out;
1273 }
1274
1275 /* Set real number of channels specified in creq->channels[] */
1276 creq->n_channels = i;
1277
1278 /* translate "Scan for SSID" request */
1279 if (wreq) {
1280 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1281 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1282 err = -EINVAL;
1283 goto out;
1284 }
1285 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1286 creq->ssids[0].ssid_len = wreq->essid_len;
1287 }
1288 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1289 creq->n_ssids = 0;
1290 }
1291
1292 for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1293 if (wiphy->bands[i])
1294 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1295
1296 rdev->scan_req = creq;
1297 err = rdev_scan(rdev, creq);
1298 if (err) {
1299 rdev->scan_req = NULL;
1300 /* creq will be freed below */
1301 } else {
1302 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1303 /* creq now owned by driver */
1304 creq = NULL;
1305 dev_hold(dev);
1306 }
1307 out:
1308 kfree(creq);
1309 return err;
1310}
1311EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1312
1313static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1314 const struct cfg80211_bss_ies *ies,
1315 char *current_ev, char *end_buf)
1316{
1317 const u8 *pos, *end, *next;
1318 struct iw_event iwe;
1319
1320 if (!ies)
1321 return current_ev;
1322
1323 /*
1324 * If needed, fragment the IEs buffer (at IE boundaries) into short
1325 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1326 */
1327 pos = ies->data;
1328 end = pos + ies->len;
1329
1330 while (end - pos > IW_GENERIC_IE_MAX) {
1331 next = pos + 2 + pos[1];
1332 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1333 next = next + 2 + next[1];
1334
1335 memset(&iwe, 0, sizeof(iwe));
1336 iwe.cmd = IWEVGENIE;
1337 iwe.u.data.length = next - pos;
1338 current_ev = iwe_stream_add_point_check(info, current_ev,
1339 end_buf, &iwe,
1340 (void *)pos);
1341 if (IS_ERR(current_ev))
1342 return current_ev;
1343 pos = next;
1344 }
1345
1346 if (end > pos) {
1347 memset(&iwe, 0, sizeof(iwe));
1348 iwe.cmd = IWEVGENIE;
1349 iwe.u.data.length = end - pos;
1350 current_ev = iwe_stream_add_point_check(info, current_ev,
1351 end_buf, &iwe,
1352 (void *)pos);
1353 if (IS_ERR(current_ev))
1354 return current_ev;
1355 }
1356
1357 return current_ev;
1358}
1359
1360static char *
1361ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1362 struct cfg80211_internal_bss *bss, char *current_ev,
1363 char *end_buf)
1364{
1365 const struct cfg80211_bss_ies *ies;
1366 struct iw_event iwe;
1367 const u8 *ie;
1368 u8 buf[50];
1369 u8 *cfg, *p, *tmp;
1370 int rem, i, sig;
1371 bool ismesh = false;
1372
1373 memset(&iwe, 0, sizeof(iwe));
1374 iwe.cmd = SIOCGIWAP;
1375 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1376 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1377 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1378 IW_EV_ADDR_LEN);
1379 if (IS_ERR(current_ev))
1380 return current_ev;
1381
1382 memset(&iwe, 0, sizeof(iwe));
1383 iwe.cmd = SIOCGIWFREQ;
1384 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1385 iwe.u.freq.e = 0;
1386 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1387 IW_EV_FREQ_LEN);
1388 if (IS_ERR(current_ev))
1389 return current_ev;
1390
1391 memset(&iwe, 0, sizeof(iwe));
1392 iwe.cmd = SIOCGIWFREQ;
1393 iwe.u.freq.m = bss->pub.channel->center_freq;
1394 iwe.u.freq.e = 6;
1395 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1396 IW_EV_FREQ_LEN);
1397 if (IS_ERR(current_ev))
1398 return current_ev;
1399
1400 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1401 memset(&iwe, 0, sizeof(iwe));
1402 iwe.cmd = IWEVQUAL;
1403 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1404 IW_QUAL_NOISE_INVALID |
1405 IW_QUAL_QUAL_UPDATED;
1406 switch (wiphy->signal_type) {
1407 case CFG80211_SIGNAL_TYPE_MBM:
1408 sig = bss->pub.signal / 100;
1409 iwe.u.qual.level = sig;
1410 iwe.u.qual.updated |= IW_QUAL_DBM;
1411 if (sig < -110) /* rather bad */
1412 sig = -110;
1413 else if (sig > -40) /* perfect */
1414 sig = -40;
1415 /* will give a range of 0 .. 70 */
1416 iwe.u.qual.qual = sig + 110;
1417 break;
1418 case CFG80211_SIGNAL_TYPE_UNSPEC:
1419 iwe.u.qual.level = bss->pub.signal;
1420 /* will give range 0 .. 100 */
1421 iwe.u.qual.qual = bss->pub.signal;
1422 break;
1423 default:
1424 /* not reached */
1425 break;
1426 }
1427 current_ev = iwe_stream_add_event_check(info, current_ev,
1428 end_buf, &iwe,
1429 IW_EV_QUAL_LEN);
1430 if (IS_ERR(current_ev))
1431 return current_ev;
1432 }
1433
1434 memset(&iwe, 0, sizeof(iwe));
1435 iwe.cmd = SIOCGIWENCODE;
1436 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1437 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1438 else
1439 iwe.u.data.flags = IW_ENCODE_DISABLED;
1440 iwe.u.data.length = 0;
1441 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1442 &iwe, "");
1443 if (IS_ERR(current_ev))
1444 return current_ev;
1445
1446 rcu_read_lock();
1447 ies = rcu_dereference(bss->pub.ies);
1448 rem = ies->len;
1449 ie = ies->data;
1450
1451 while (rem >= 2) {
1452 /* invalid data */
1453 if (ie[1] > rem - 2)
1454 break;
1455
1456 switch (ie[0]) {
1457 case WLAN_EID_SSID:
1458 memset(&iwe, 0, sizeof(iwe));
1459 iwe.cmd = SIOCGIWESSID;
1460 iwe.u.data.length = ie[1];
1461 iwe.u.data.flags = 1;
1462 current_ev = iwe_stream_add_point_check(info,
1463 current_ev,
1464 end_buf, &iwe,
1465 (u8 *)ie + 2);
1466 if (IS_ERR(current_ev))
1467 goto unlock;
1468 break;
1469 case WLAN_EID_MESH_ID:
1470 memset(&iwe, 0, sizeof(iwe));
1471 iwe.cmd = SIOCGIWESSID;
1472 iwe.u.data.length = ie[1];
1473 iwe.u.data.flags = 1;
1474 current_ev = iwe_stream_add_point_check(info,
1475 current_ev,
1476 end_buf, &iwe,
1477 (u8 *)ie + 2);
1478 if (IS_ERR(current_ev))
1479 goto unlock;
1480 break;
1481 case WLAN_EID_MESH_CONFIG:
1482 ismesh = true;
1483 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1484 break;
1485 cfg = (u8 *)ie + 2;
1486 memset(&iwe, 0, sizeof(iwe));
1487 iwe.cmd = IWEVCUSTOM;
1488 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1489 "0x%02X", cfg[0]);
1490 iwe.u.data.length = strlen(buf);
1491 current_ev = iwe_stream_add_point_check(info,
1492 current_ev,
1493 end_buf,
1494 &iwe, buf);
1495 if (IS_ERR(current_ev))
1496 goto unlock;
1497 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1498 cfg[1]);
1499 iwe.u.data.length = strlen(buf);
1500 current_ev = iwe_stream_add_point_check(info,
1501 current_ev,
1502 end_buf,
1503 &iwe, buf);
1504 if (IS_ERR(current_ev))
1505 goto unlock;
1506 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1507 cfg[2]);
1508 iwe.u.data.length = strlen(buf);
1509 current_ev = iwe_stream_add_point_check(info,
1510 current_ev,
1511 end_buf,
1512 &iwe, buf);
1513 if (IS_ERR(current_ev))
1514 goto unlock;
1515 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1516 iwe.u.data.length = strlen(buf);
1517 current_ev = iwe_stream_add_point_check(info,
1518 current_ev,
1519 end_buf,
1520 &iwe, buf);
1521 if (IS_ERR(current_ev))
1522 goto unlock;
1523 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1524 iwe.u.data.length = strlen(buf);
1525 current_ev = iwe_stream_add_point_check(info,
1526 current_ev,
1527 end_buf,
1528 &iwe, buf);
1529 if (IS_ERR(current_ev))
1530 goto unlock;
1531 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1532 iwe.u.data.length = strlen(buf);
1533 current_ev = iwe_stream_add_point_check(info,
1534 current_ev,
1535 end_buf,
1536 &iwe, buf);
1537 if (IS_ERR(current_ev))
1538 goto unlock;
1539 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1540 iwe.u.data.length = strlen(buf);
1541 current_ev = iwe_stream_add_point_check(info,
1542 current_ev,
1543 end_buf,
1544 &iwe, buf);
1545 if (IS_ERR(current_ev))
1546 goto unlock;
1547 break;
1548 case WLAN_EID_SUPP_RATES:
1549 case WLAN_EID_EXT_SUPP_RATES:
1550 /* display all supported rates in readable format */
1551 p = current_ev + iwe_stream_lcp_len(info);
1552
1553 memset(&iwe, 0, sizeof(iwe));
1554 iwe.cmd = SIOCGIWRATE;
1555 /* Those two flags are ignored... */
1556 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1557
1558 for (i = 0; i < ie[1]; i++) {
1559 iwe.u.bitrate.value =
1560 ((ie[i + 2] & 0x7f) * 500000);
1561 tmp = p;
1562 p = iwe_stream_add_value(info, current_ev, p,
1563 end_buf, &iwe,
1564 IW_EV_PARAM_LEN);
1565 if (p == tmp) {
1566 current_ev = ERR_PTR(-E2BIG);
1567 goto unlock;
1568 }
1569 }
1570 current_ev = p;
1571 break;
1572 }
1573 rem -= ie[1] + 2;
1574 ie += ie[1] + 2;
1575 }
1576
1577 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1578 ismesh) {
1579 memset(&iwe, 0, sizeof(iwe));
1580 iwe.cmd = SIOCGIWMODE;
1581 if (ismesh)
1582 iwe.u.mode = IW_MODE_MESH;
1583 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1584 iwe.u.mode = IW_MODE_MASTER;
1585 else
1586 iwe.u.mode = IW_MODE_ADHOC;
1587 current_ev = iwe_stream_add_event_check(info, current_ev,
1588 end_buf, &iwe,
1589 IW_EV_UINT_LEN);
1590 if (IS_ERR(current_ev))
1591 goto unlock;
1592 }
1593
1594 memset(&iwe, 0, sizeof(iwe));
1595 iwe.cmd = IWEVCUSTOM;
1596 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1597 iwe.u.data.length = strlen(buf);
1598 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1599 &iwe, buf);
1600 if (IS_ERR(current_ev))
1601 goto unlock;
1602 memset(&iwe, 0, sizeof(iwe));
1603 iwe.cmd = IWEVCUSTOM;
1604 sprintf(buf, " Last beacon: %ums ago",
1605 elapsed_jiffies_msecs(bss->ts));
1606 iwe.u.data.length = strlen(buf);
1607 current_ev = iwe_stream_add_point_check(info, current_ev,
1608 end_buf, &iwe, buf);
1609 if (IS_ERR(current_ev))
1610 goto unlock;
1611
1612 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1613
1614 unlock:
1615 rcu_read_unlock();
1616 return current_ev;
1617}
1618
1619
1620static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1621 struct iw_request_info *info,
1622 char *buf, size_t len)
1623{
1624 char *current_ev = buf;
1625 char *end_buf = buf + len;
1626 struct cfg80211_internal_bss *bss;
1627 int err = 0;
1628
1629 spin_lock_bh(&rdev->bss_lock);
1630 cfg80211_bss_expire(rdev);
1631
1632 list_for_each_entry(bss, &rdev->bss_list, list) {
1633 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1634 err = -E2BIG;
1635 break;
1636 }
1637 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1638 current_ev, end_buf);
1639 if (IS_ERR(current_ev)) {
1640 err = PTR_ERR(current_ev);
1641 break;
1642 }
1643 }
1644 spin_unlock_bh(&rdev->bss_lock);
1645
1646 if (err)
1647 return err;
1648 return current_ev - buf;
1649}
1650
1651
1652int cfg80211_wext_giwscan(struct net_device *dev,
1653 struct iw_request_info *info,
1654 struct iw_point *data, char *extra)
1655{
1656 struct cfg80211_registered_device *rdev;
1657 int res;
1658
1659 if (!netif_running(dev))
1660 return -ENETDOWN;
1661
1662 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1663
1664 if (IS_ERR(rdev))
1665 return PTR_ERR(rdev);
1666
1667 if (rdev->scan_req || rdev->scan_msg)
1668 return -EAGAIN;
1669
1670 res = ieee80211_scan_results(rdev, info, extra, data->length);
1671 data->length = 0;
1672 if (res >= 0) {
1673 data->length = res;
1674 res = 0;
1675 }
1676
1677 return res;
1678}
1679EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1680#endif