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nl80211: rework {sched_,}scan event related functions
[mirror_ubuntu-bionic-kernel.git] / net / wireless / scan.c
1 /*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 * Copyright 2013-2014 Intel Mobile Communications GmbH
6 * Copyright 2016 Intel Deutschland GmbH
7 */
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/netdevice.h>
12 #include <linux/wireless.h>
13 #include <linux/nl80211.h>
14 #include <linux/etherdevice.h>
15 #include <net/arp.h>
16 #include <net/cfg80211.h>
17 #include <net/cfg80211-wext.h>
18 #include <net/iw_handler.h>
19 #include "core.h"
20 #include "nl80211.h"
21 #include "wext-compat.h"
22 #include "rdev-ops.h"
23
24 /**
25 * DOC: BSS tree/list structure
26 *
27 * At the top level, the BSS list is kept in both a list in each
28 * registered device (@bss_list) as well as an RB-tree for faster
29 * lookup. In the RB-tree, entries can be looked up using their
30 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
31 * for other BSSes.
32 *
33 * Due to the possibility of hidden SSIDs, there's a second level
34 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
35 * The hidden_list connects all BSSes belonging to a single AP
36 * that has a hidden SSID, and connects beacon and probe response
37 * entries. For a probe response entry for a hidden SSID, the
38 * hidden_beacon_bss pointer points to the BSS struct holding the
39 * beacon's information.
40 *
41 * Reference counting is done for all these references except for
42 * the hidden_list, so that a beacon BSS struct that is otherwise
43 * not referenced has one reference for being on the bss_list and
44 * one for each probe response entry that points to it using the
45 * hidden_beacon_bss pointer. When a BSS struct that has such a
46 * pointer is get/put, the refcount update is also propagated to
47 * the referenced struct, this ensure that it cannot get removed
48 * while somebody is using the probe response version.
49 *
50 * Note that the hidden_beacon_bss pointer never changes, due to
51 * the reference counting. Therefore, no locking is needed for
52 * it.
53 *
54 * Also note that the hidden_beacon_bss pointer is only relevant
55 * if the driver uses something other than the IEs, e.g. private
56 * data stored stored in the BSS struct, since the beacon IEs are
57 * also linked into the probe response struct.
58 */
59
60 /*
61 * Limit the number of BSS entries stored in mac80211. Each one is
62 * a bit over 4k at most, so this limits to roughly 4-5M of memory.
63 * If somebody wants to really attack this though, they'd likely
64 * use small beacons, and only one type of frame, limiting each of
65 * the entries to a much smaller size (in order to generate more
66 * entries in total, so overhead is bigger.)
67 */
68 static int bss_entries_limit = 1000;
69 module_param(bss_entries_limit, int, 0644);
70 MODULE_PARM_DESC(bss_entries_limit,
71 "limit to number of scan BSS entries (per wiphy, default 1000)");
72
73 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
74
75 static void bss_free(struct cfg80211_internal_bss *bss)
76 {
77 struct cfg80211_bss_ies *ies;
78
79 if (WARN_ON(atomic_read(&bss->hold)))
80 return;
81
82 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
83 if (ies && !bss->pub.hidden_beacon_bss)
84 kfree_rcu(ies, rcu_head);
85 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
86 if (ies)
87 kfree_rcu(ies, rcu_head);
88
89 /*
90 * This happens when the module is removed, it doesn't
91 * really matter any more save for completeness
92 */
93 if (!list_empty(&bss->hidden_list))
94 list_del(&bss->hidden_list);
95
96 kfree(bss);
97 }
98
99 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
100 struct cfg80211_internal_bss *bss)
101 {
102 lockdep_assert_held(&rdev->bss_lock);
103
104 bss->refcount++;
105 if (bss->pub.hidden_beacon_bss) {
106 bss = container_of(bss->pub.hidden_beacon_bss,
107 struct cfg80211_internal_bss,
108 pub);
109 bss->refcount++;
110 }
111 }
112
113 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
114 struct cfg80211_internal_bss *bss)
115 {
116 lockdep_assert_held(&rdev->bss_lock);
117
118 if (bss->pub.hidden_beacon_bss) {
119 struct cfg80211_internal_bss *hbss;
120 hbss = container_of(bss->pub.hidden_beacon_bss,
121 struct cfg80211_internal_bss,
122 pub);
123 hbss->refcount--;
124 if (hbss->refcount == 0)
125 bss_free(hbss);
126 }
127 bss->refcount--;
128 if (bss->refcount == 0)
129 bss_free(bss);
130 }
131
132 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
133 struct cfg80211_internal_bss *bss)
134 {
135 lockdep_assert_held(&rdev->bss_lock);
136
137 if (!list_empty(&bss->hidden_list)) {
138 /*
139 * don't remove the beacon entry if it has
140 * probe responses associated with it
141 */
142 if (!bss->pub.hidden_beacon_bss)
143 return false;
144 /*
145 * if it's a probe response entry break its
146 * link to the other entries in the group
147 */
148 list_del_init(&bss->hidden_list);
149 }
150
151 list_del_init(&bss->list);
152 rb_erase(&bss->rbn, &rdev->bss_tree);
153 rdev->bss_entries--;
154 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
155 "rdev bss entries[%d]/list[empty:%d] corruption\n",
156 rdev->bss_entries, list_empty(&rdev->bss_list));
157 bss_ref_put(rdev, bss);
158 return true;
159 }
160
161 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
162 unsigned long expire_time)
163 {
164 struct cfg80211_internal_bss *bss, *tmp;
165 bool expired = false;
166
167 lockdep_assert_held(&rdev->bss_lock);
168
169 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
170 if (atomic_read(&bss->hold))
171 continue;
172 if (!time_after(expire_time, bss->ts))
173 continue;
174
175 if (__cfg80211_unlink_bss(rdev, bss))
176 expired = true;
177 }
178
179 if (expired)
180 rdev->bss_generation++;
181 }
182
183 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
184 {
185 struct cfg80211_internal_bss *bss, *oldest = NULL;
186 bool ret;
187
188 lockdep_assert_held(&rdev->bss_lock);
189
190 list_for_each_entry(bss, &rdev->bss_list, list) {
191 if (atomic_read(&bss->hold))
192 continue;
193
194 if (!list_empty(&bss->hidden_list) &&
195 !bss->pub.hidden_beacon_bss)
196 continue;
197
198 if (oldest && time_before(oldest->ts, bss->ts))
199 continue;
200 oldest = bss;
201 }
202
203 if (WARN_ON(!oldest))
204 return false;
205
206 /*
207 * The callers make sure to increase rdev->bss_generation if anything
208 * gets removed (and a new entry added), so there's no need to also do
209 * it here.
210 */
211
212 ret = __cfg80211_unlink_bss(rdev, oldest);
213 WARN_ON(!ret);
214 return ret;
215 }
216
217 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
218 bool send_message)
219 {
220 struct cfg80211_scan_request *request;
221 struct wireless_dev *wdev;
222 struct sk_buff *msg;
223 #ifdef CONFIG_CFG80211_WEXT
224 union iwreq_data wrqu;
225 #endif
226
227 ASSERT_RTNL();
228
229 if (rdev->scan_msg) {
230 nl80211_send_scan_msg(rdev, rdev->scan_msg);
231 rdev->scan_msg = NULL;
232 return;
233 }
234
235 request = rdev->scan_req;
236 if (!request)
237 return;
238
239 wdev = request->wdev;
240
241 /*
242 * This must be before sending the other events!
243 * Otherwise, wpa_supplicant gets completely confused with
244 * wext events.
245 */
246 if (wdev->netdev)
247 cfg80211_sme_scan_done(wdev->netdev);
248
249 if (!request->info.aborted &&
250 request->flags & NL80211_SCAN_FLAG_FLUSH) {
251 /* flush entries from previous scans */
252 spin_lock_bh(&rdev->bss_lock);
253 __cfg80211_bss_expire(rdev, request->scan_start);
254 spin_unlock_bh(&rdev->bss_lock);
255 }
256
257 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
258
259 #ifdef CONFIG_CFG80211_WEXT
260 if (wdev->netdev && !request->info.aborted) {
261 memset(&wrqu, 0, sizeof(wrqu));
262
263 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
264 }
265 #endif
266
267 if (wdev->netdev)
268 dev_put(wdev->netdev);
269
270 rdev->scan_req = NULL;
271 kfree(request);
272
273 if (!send_message)
274 rdev->scan_msg = msg;
275 else
276 nl80211_send_scan_msg(rdev, msg);
277 }
278
279 void __cfg80211_scan_done(struct work_struct *wk)
280 {
281 struct cfg80211_registered_device *rdev;
282
283 rdev = container_of(wk, struct cfg80211_registered_device,
284 scan_done_wk);
285
286 rtnl_lock();
287 ___cfg80211_scan_done(rdev, true);
288 rtnl_unlock();
289 }
290
291 void cfg80211_scan_done(struct cfg80211_scan_request *request,
292 struct cfg80211_scan_info *info)
293 {
294 trace_cfg80211_scan_done(request, info);
295 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
296
297 request->info = *info;
298 request->notified = true;
299 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
300 }
301 EXPORT_SYMBOL(cfg80211_scan_done);
302
303 void __cfg80211_sched_scan_results(struct work_struct *wk)
304 {
305 struct cfg80211_registered_device *rdev;
306 struct cfg80211_sched_scan_request *request;
307
308 rdev = container_of(wk, struct cfg80211_registered_device,
309 sched_scan_results_wk);
310
311 rtnl_lock();
312
313 request = rtnl_dereference(rdev->sched_scan_req);
314
315 /* we don't have sched_scan_req anymore if the scan is stopping */
316 if (request) {
317 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
318 /* flush entries from previous scans */
319 spin_lock_bh(&rdev->bss_lock);
320 __cfg80211_bss_expire(rdev, request->scan_start);
321 spin_unlock_bh(&rdev->bss_lock);
322 request->scan_start = jiffies;
323 }
324 nl80211_send_sched_scan(rdev, request->dev,
325 NL80211_CMD_SCHED_SCAN_RESULTS);
326 }
327
328 rtnl_unlock();
329 }
330
331 void cfg80211_sched_scan_results(struct wiphy *wiphy)
332 {
333 trace_cfg80211_sched_scan_results(wiphy);
334 /* ignore if we're not scanning */
335
336 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
337 queue_work(cfg80211_wq,
338 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
339 }
340 EXPORT_SYMBOL(cfg80211_sched_scan_results);
341
342 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
343 {
344 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
345
346 ASSERT_RTNL();
347
348 trace_cfg80211_sched_scan_stopped(wiphy);
349
350 __cfg80211_stop_sched_scan(rdev, true);
351 }
352 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
353
354 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
355 {
356 rtnl_lock();
357 cfg80211_sched_scan_stopped_rtnl(wiphy);
358 rtnl_unlock();
359 }
360 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
361
362 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
363 bool driver_initiated)
364 {
365 struct cfg80211_sched_scan_request *sched_scan_req;
366 struct net_device *dev;
367
368 ASSERT_RTNL();
369
370 if (!rdev->sched_scan_req)
371 return -ENOENT;
372
373 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
374 dev = sched_scan_req->dev;
375
376 if (!driver_initiated) {
377 int err = rdev_sched_scan_stop(rdev, dev);
378 if (err)
379 return err;
380 }
381
382 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
383
384 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
385 kfree_rcu(sched_scan_req, rcu_head);
386
387 return 0;
388 }
389
390 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
391 unsigned long age_secs)
392 {
393 struct cfg80211_internal_bss *bss;
394 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
395
396 spin_lock_bh(&rdev->bss_lock);
397 list_for_each_entry(bss, &rdev->bss_list, list)
398 bss->ts -= age_jiffies;
399 spin_unlock_bh(&rdev->bss_lock);
400 }
401
402 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
403 {
404 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
405 }
406
407 const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,
408 const u8 *match, int match_len,
409 int match_offset)
410 {
411 /* match_offset can't be smaller than 2, unless match_len is
412 * zero, in which case match_offset must be zero as well.
413 */
414 if (WARN_ON((match_len && match_offset < 2) ||
415 (!match_len && match_offset)))
416 return NULL;
417
418 while (len >= 2 && len >= ies[1] + 2) {
419 if ((ies[0] == eid) &&
420 (ies[1] + 2 >= match_offset + match_len) &&
421 !memcmp(ies + match_offset, match, match_len))
422 return ies;
423
424 len -= ies[1] + 2;
425 ies += ies[1] + 2;
426 }
427
428 return NULL;
429 }
430 EXPORT_SYMBOL(cfg80211_find_ie_match);
431
432 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
433 const u8 *ies, int len)
434 {
435 const u8 *ie;
436 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
437 int match_len = (oui_type < 0) ? 3 : sizeof(match);
438
439 if (WARN_ON(oui_type > 0xff))
440 return NULL;
441
442 ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
443 match, match_len, 2);
444
445 if (ie && (ie[1] < 4))
446 return NULL;
447
448 return ie;
449 }
450 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
451
452 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
453 const u8 *ssid, size_t ssid_len)
454 {
455 const struct cfg80211_bss_ies *ies;
456 const u8 *ssidie;
457
458 if (bssid && !ether_addr_equal(a->bssid, bssid))
459 return false;
460
461 if (!ssid)
462 return true;
463
464 ies = rcu_access_pointer(a->ies);
465 if (!ies)
466 return false;
467 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
468 if (!ssidie)
469 return false;
470 if (ssidie[1] != ssid_len)
471 return false;
472 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
473 }
474
475 /**
476 * enum bss_compare_mode - BSS compare mode
477 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
478 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
479 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
480 */
481 enum bss_compare_mode {
482 BSS_CMP_REGULAR,
483 BSS_CMP_HIDE_ZLEN,
484 BSS_CMP_HIDE_NUL,
485 };
486
487 static int cmp_bss(struct cfg80211_bss *a,
488 struct cfg80211_bss *b,
489 enum bss_compare_mode mode)
490 {
491 const struct cfg80211_bss_ies *a_ies, *b_ies;
492 const u8 *ie1 = NULL;
493 const u8 *ie2 = NULL;
494 int i, r;
495
496 if (a->channel != b->channel)
497 return b->channel->center_freq - a->channel->center_freq;
498
499 a_ies = rcu_access_pointer(a->ies);
500 if (!a_ies)
501 return -1;
502 b_ies = rcu_access_pointer(b->ies);
503 if (!b_ies)
504 return 1;
505
506 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
507 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
508 a_ies->data, a_ies->len);
509 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
510 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
511 b_ies->data, b_ies->len);
512 if (ie1 && ie2) {
513 int mesh_id_cmp;
514
515 if (ie1[1] == ie2[1])
516 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
517 else
518 mesh_id_cmp = ie2[1] - ie1[1];
519
520 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
521 a_ies->data, a_ies->len);
522 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
523 b_ies->data, b_ies->len);
524 if (ie1 && ie2) {
525 if (mesh_id_cmp)
526 return mesh_id_cmp;
527 if (ie1[1] != ie2[1])
528 return ie2[1] - ie1[1];
529 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
530 }
531 }
532
533 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
534 if (r)
535 return r;
536
537 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
538 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
539
540 if (!ie1 && !ie2)
541 return 0;
542
543 /*
544 * Note that with "hide_ssid", the function returns a match if
545 * the already-present BSS ("b") is a hidden SSID beacon for
546 * the new BSS ("a").
547 */
548
549 /* sort missing IE before (left of) present IE */
550 if (!ie1)
551 return -1;
552 if (!ie2)
553 return 1;
554
555 switch (mode) {
556 case BSS_CMP_HIDE_ZLEN:
557 /*
558 * In ZLEN mode we assume the BSS entry we're
559 * looking for has a zero-length SSID. So if
560 * the one we're looking at right now has that,
561 * return 0. Otherwise, return the difference
562 * in length, but since we're looking for the
563 * 0-length it's really equivalent to returning
564 * the length of the one we're looking at.
565 *
566 * No content comparison is needed as we assume
567 * the content length is zero.
568 */
569 return ie2[1];
570 case BSS_CMP_REGULAR:
571 default:
572 /* sort by length first, then by contents */
573 if (ie1[1] != ie2[1])
574 return ie2[1] - ie1[1];
575 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
576 case BSS_CMP_HIDE_NUL:
577 if (ie1[1] != ie2[1])
578 return ie2[1] - ie1[1];
579 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
580 for (i = 0; i < ie2[1]; i++)
581 if (ie2[i + 2])
582 return -1;
583 return 0;
584 }
585 }
586
587 static bool cfg80211_bss_type_match(u16 capability,
588 enum nl80211_band band,
589 enum ieee80211_bss_type bss_type)
590 {
591 bool ret = true;
592 u16 mask, val;
593
594 if (bss_type == IEEE80211_BSS_TYPE_ANY)
595 return ret;
596
597 if (band == NL80211_BAND_60GHZ) {
598 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
599 switch (bss_type) {
600 case IEEE80211_BSS_TYPE_ESS:
601 val = WLAN_CAPABILITY_DMG_TYPE_AP;
602 break;
603 case IEEE80211_BSS_TYPE_PBSS:
604 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
605 break;
606 case IEEE80211_BSS_TYPE_IBSS:
607 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
608 break;
609 default:
610 return false;
611 }
612 } else {
613 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
614 switch (bss_type) {
615 case IEEE80211_BSS_TYPE_ESS:
616 val = WLAN_CAPABILITY_ESS;
617 break;
618 case IEEE80211_BSS_TYPE_IBSS:
619 val = WLAN_CAPABILITY_IBSS;
620 break;
621 case IEEE80211_BSS_TYPE_MBSS:
622 val = 0;
623 break;
624 default:
625 return false;
626 }
627 }
628
629 ret = ((capability & mask) == val);
630 return ret;
631 }
632
633 /* Returned bss is reference counted and must be cleaned up appropriately. */
634 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
635 struct ieee80211_channel *channel,
636 const u8 *bssid,
637 const u8 *ssid, size_t ssid_len,
638 enum ieee80211_bss_type bss_type,
639 enum ieee80211_privacy privacy)
640 {
641 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
642 struct cfg80211_internal_bss *bss, *res = NULL;
643 unsigned long now = jiffies;
644 int bss_privacy;
645
646 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
647 privacy);
648
649 spin_lock_bh(&rdev->bss_lock);
650
651 list_for_each_entry(bss, &rdev->bss_list, list) {
652 if (!cfg80211_bss_type_match(bss->pub.capability,
653 bss->pub.channel->band, bss_type))
654 continue;
655
656 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
657 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
658 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
659 continue;
660 if (channel && bss->pub.channel != channel)
661 continue;
662 if (!is_valid_ether_addr(bss->pub.bssid))
663 continue;
664 /* Don't get expired BSS structs */
665 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
666 !atomic_read(&bss->hold))
667 continue;
668 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
669 res = bss;
670 bss_ref_get(rdev, res);
671 break;
672 }
673 }
674
675 spin_unlock_bh(&rdev->bss_lock);
676 if (!res)
677 return NULL;
678 trace_cfg80211_return_bss(&res->pub);
679 return &res->pub;
680 }
681 EXPORT_SYMBOL(cfg80211_get_bss);
682
683 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
684 struct cfg80211_internal_bss *bss)
685 {
686 struct rb_node **p = &rdev->bss_tree.rb_node;
687 struct rb_node *parent = NULL;
688 struct cfg80211_internal_bss *tbss;
689 int cmp;
690
691 while (*p) {
692 parent = *p;
693 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
694
695 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
696
697 if (WARN_ON(!cmp)) {
698 /* will sort of leak this BSS */
699 return;
700 }
701
702 if (cmp < 0)
703 p = &(*p)->rb_left;
704 else
705 p = &(*p)->rb_right;
706 }
707
708 rb_link_node(&bss->rbn, parent, p);
709 rb_insert_color(&bss->rbn, &rdev->bss_tree);
710 }
711
712 static struct cfg80211_internal_bss *
713 rb_find_bss(struct cfg80211_registered_device *rdev,
714 struct cfg80211_internal_bss *res,
715 enum bss_compare_mode mode)
716 {
717 struct rb_node *n = rdev->bss_tree.rb_node;
718 struct cfg80211_internal_bss *bss;
719 int r;
720
721 while (n) {
722 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
723 r = cmp_bss(&res->pub, &bss->pub, mode);
724
725 if (r == 0)
726 return bss;
727 else if (r < 0)
728 n = n->rb_left;
729 else
730 n = n->rb_right;
731 }
732
733 return NULL;
734 }
735
736 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
737 struct cfg80211_internal_bss *new)
738 {
739 const struct cfg80211_bss_ies *ies;
740 struct cfg80211_internal_bss *bss;
741 const u8 *ie;
742 int i, ssidlen;
743 u8 fold = 0;
744 u32 n_entries = 0;
745
746 ies = rcu_access_pointer(new->pub.beacon_ies);
747 if (WARN_ON(!ies))
748 return false;
749
750 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
751 if (!ie) {
752 /* nothing to do */
753 return true;
754 }
755
756 ssidlen = ie[1];
757 for (i = 0; i < ssidlen; i++)
758 fold |= ie[2 + i];
759
760 if (fold) {
761 /* not a hidden SSID */
762 return true;
763 }
764
765 /* This is the bad part ... */
766
767 list_for_each_entry(bss, &rdev->bss_list, list) {
768 /*
769 * we're iterating all the entries anyway, so take the
770 * opportunity to validate the list length accounting
771 */
772 n_entries++;
773
774 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
775 continue;
776 if (bss->pub.channel != new->pub.channel)
777 continue;
778 if (bss->pub.scan_width != new->pub.scan_width)
779 continue;
780 if (rcu_access_pointer(bss->pub.beacon_ies))
781 continue;
782 ies = rcu_access_pointer(bss->pub.ies);
783 if (!ies)
784 continue;
785 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
786 if (!ie)
787 continue;
788 if (ssidlen && ie[1] != ssidlen)
789 continue;
790 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
791 continue;
792 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
793 list_del(&bss->hidden_list);
794 /* combine them */
795 list_add(&bss->hidden_list, &new->hidden_list);
796 bss->pub.hidden_beacon_bss = &new->pub;
797 new->refcount += bss->refcount;
798 rcu_assign_pointer(bss->pub.beacon_ies,
799 new->pub.beacon_ies);
800 }
801
802 WARN_ONCE(n_entries != rdev->bss_entries,
803 "rdev bss entries[%d]/list[len:%d] corruption\n",
804 rdev->bss_entries, n_entries);
805
806 return true;
807 }
808
809 /* Returned bss is reference counted and must be cleaned up appropriately. */
810 static struct cfg80211_internal_bss *
811 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
812 struct cfg80211_internal_bss *tmp,
813 bool signal_valid)
814 {
815 struct cfg80211_internal_bss *found = NULL;
816
817 if (WARN_ON(!tmp->pub.channel))
818 return NULL;
819
820 tmp->ts = jiffies;
821
822 spin_lock_bh(&rdev->bss_lock);
823
824 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
825 spin_unlock_bh(&rdev->bss_lock);
826 return NULL;
827 }
828
829 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
830
831 if (found) {
832 /* Update IEs */
833 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
834 const struct cfg80211_bss_ies *old;
835
836 old = rcu_access_pointer(found->pub.proberesp_ies);
837
838 rcu_assign_pointer(found->pub.proberesp_ies,
839 tmp->pub.proberesp_ies);
840 /* Override possible earlier Beacon frame IEs */
841 rcu_assign_pointer(found->pub.ies,
842 tmp->pub.proberesp_ies);
843 if (old)
844 kfree_rcu((struct cfg80211_bss_ies *)old,
845 rcu_head);
846 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
847 const struct cfg80211_bss_ies *old;
848 struct cfg80211_internal_bss *bss;
849
850 if (found->pub.hidden_beacon_bss &&
851 !list_empty(&found->hidden_list)) {
852 const struct cfg80211_bss_ies *f;
853
854 /*
855 * The found BSS struct is one of the probe
856 * response members of a group, but we're
857 * receiving a beacon (beacon_ies in the tmp
858 * bss is used). This can only mean that the
859 * AP changed its beacon from not having an
860 * SSID to showing it, which is confusing so
861 * drop this information.
862 */
863
864 f = rcu_access_pointer(tmp->pub.beacon_ies);
865 kfree_rcu((struct cfg80211_bss_ies *)f,
866 rcu_head);
867 goto drop;
868 }
869
870 old = rcu_access_pointer(found->pub.beacon_ies);
871
872 rcu_assign_pointer(found->pub.beacon_ies,
873 tmp->pub.beacon_ies);
874
875 /* Override IEs if they were from a beacon before */
876 if (old == rcu_access_pointer(found->pub.ies))
877 rcu_assign_pointer(found->pub.ies,
878 tmp->pub.beacon_ies);
879
880 /* Assign beacon IEs to all sub entries */
881 list_for_each_entry(bss, &found->hidden_list,
882 hidden_list) {
883 const struct cfg80211_bss_ies *ies;
884
885 ies = rcu_access_pointer(bss->pub.beacon_ies);
886 WARN_ON(ies != old);
887
888 rcu_assign_pointer(bss->pub.beacon_ies,
889 tmp->pub.beacon_ies);
890 }
891
892 if (old)
893 kfree_rcu((struct cfg80211_bss_ies *)old,
894 rcu_head);
895 }
896
897 found->pub.beacon_interval = tmp->pub.beacon_interval;
898 /*
899 * don't update the signal if beacon was heard on
900 * adjacent channel.
901 */
902 if (signal_valid)
903 found->pub.signal = tmp->pub.signal;
904 found->pub.capability = tmp->pub.capability;
905 found->ts = tmp->ts;
906 found->ts_boottime = tmp->ts_boottime;
907 found->parent_tsf = tmp->parent_tsf;
908 ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
909 } else {
910 struct cfg80211_internal_bss *new;
911 struct cfg80211_internal_bss *hidden;
912 struct cfg80211_bss_ies *ies;
913
914 /*
915 * create a copy -- the "res" variable that is passed in
916 * is allocated on the stack since it's not needed in the
917 * more common case of an update
918 */
919 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
920 GFP_ATOMIC);
921 if (!new) {
922 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
923 if (ies)
924 kfree_rcu(ies, rcu_head);
925 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
926 if (ies)
927 kfree_rcu(ies, rcu_head);
928 goto drop;
929 }
930 memcpy(new, tmp, sizeof(*new));
931 new->refcount = 1;
932 INIT_LIST_HEAD(&new->hidden_list);
933
934 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
935 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
936 if (!hidden)
937 hidden = rb_find_bss(rdev, tmp,
938 BSS_CMP_HIDE_NUL);
939 if (hidden) {
940 new->pub.hidden_beacon_bss = &hidden->pub;
941 list_add(&new->hidden_list,
942 &hidden->hidden_list);
943 hidden->refcount++;
944 rcu_assign_pointer(new->pub.beacon_ies,
945 hidden->pub.beacon_ies);
946 }
947 } else {
948 /*
949 * Ok so we found a beacon, and don't have an entry. If
950 * it's a beacon with hidden SSID, we might be in for an
951 * expensive search for any probe responses that should
952 * be grouped with this beacon for updates ...
953 */
954 if (!cfg80211_combine_bsses(rdev, new)) {
955 kfree(new);
956 goto drop;
957 }
958 }
959
960 if (rdev->bss_entries >= bss_entries_limit &&
961 !cfg80211_bss_expire_oldest(rdev)) {
962 kfree(new);
963 goto drop;
964 }
965
966 list_add_tail(&new->list, &rdev->bss_list);
967 rdev->bss_entries++;
968 rb_insert_bss(rdev, new);
969 found = new;
970 }
971
972 rdev->bss_generation++;
973 bss_ref_get(rdev, found);
974 spin_unlock_bh(&rdev->bss_lock);
975
976 return found;
977 drop:
978 spin_unlock_bh(&rdev->bss_lock);
979 return NULL;
980 }
981
982 static struct ieee80211_channel *
983 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
984 struct ieee80211_channel *channel)
985 {
986 const u8 *tmp;
987 u32 freq;
988 int channel_number = -1;
989
990 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
991 if (tmp && tmp[1] == 1) {
992 channel_number = tmp[2];
993 } else {
994 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
995 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
996 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
997
998 channel_number = htop->primary_chan;
999 }
1000 }
1001
1002 if (channel_number < 0)
1003 return channel;
1004
1005 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
1006 channel = ieee80211_get_channel(wiphy, freq);
1007 if (!channel)
1008 return NULL;
1009 if (channel->flags & IEEE80211_CHAN_DISABLED)
1010 return NULL;
1011 return channel;
1012 }
1013
1014 /* Returned bss is reference counted and must be cleaned up appropriately. */
1015 struct cfg80211_bss *
1016 cfg80211_inform_bss_data(struct wiphy *wiphy,
1017 struct cfg80211_inform_bss *data,
1018 enum cfg80211_bss_frame_type ftype,
1019 const u8 *bssid, u64 tsf, u16 capability,
1020 u16 beacon_interval, const u8 *ie, size_t ielen,
1021 gfp_t gfp)
1022 {
1023 struct cfg80211_bss_ies *ies;
1024 struct ieee80211_channel *channel;
1025 struct cfg80211_internal_bss tmp = {}, *res;
1026 int bss_type;
1027 bool signal_valid;
1028
1029 if (WARN_ON(!wiphy))
1030 return NULL;
1031
1032 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1033 (data->signal < 0 || data->signal > 100)))
1034 return NULL;
1035
1036 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan);
1037 if (!channel)
1038 return NULL;
1039
1040 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1041 tmp.pub.channel = channel;
1042 tmp.pub.scan_width = data->scan_width;
1043 tmp.pub.signal = data->signal;
1044 tmp.pub.beacon_interval = beacon_interval;
1045 tmp.pub.capability = capability;
1046 tmp.ts_boottime = data->boottime_ns;
1047
1048 /*
1049 * If we do not know here whether the IEs are from a Beacon or Probe
1050 * Response frame, we need to pick one of the options and only use it
1051 * with the driver that does not provide the full Beacon/Probe Response
1052 * frame. Use Beacon frame pointer to avoid indicating that this should
1053 * override the IEs pointer should we have received an earlier
1054 * indication of Probe Response data.
1055 */
1056 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1057 if (!ies)
1058 return NULL;
1059 ies->len = ielen;
1060 ies->tsf = tsf;
1061 ies->from_beacon = false;
1062 memcpy(ies->data, ie, ielen);
1063
1064 switch (ftype) {
1065 case CFG80211_BSS_FTYPE_BEACON:
1066 ies->from_beacon = true;
1067 /* fall through to assign */
1068 case CFG80211_BSS_FTYPE_UNKNOWN:
1069 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1070 break;
1071 case CFG80211_BSS_FTYPE_PRESP:
1072 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1073 break;
1074 }
1075 rcu_assign_pointer(tmp.pub.ies, ies);
1076
1077 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1078 wiphy->max_adj_channel_rssi_comp;
1079 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1080 if (!res)
1081 return NULL;
1082
1083 if (channel->band == NL80211_BAND_60GHZ) {
1084 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1085 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1086 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1087 regulatory_hint_found_beacon(wiphy, channel, gfp);
1088 } else {
1089 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1090 regulatory_hint_found_beacon(wiphy, channel, gfp);
1091 }
1092
1093 trace_cfg80211_return_bss(&res->pub);
1094 /* cfg80211_bss_update gives us a referenced result */
1095 return &res->pub;
1096 }
1097 EXPORT_SYMBOL(cfg80211_inform_bss_data);
1098
1099 /* cfg80211_inform_bss_width_frame helper */
1100 struct cfg80211_bss *
1101 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1102 struct cfg80211_inform_bss *data,
1103 struct ieee80211_mgmt *mgmt, size_t len,
1104 gfp_t gfp)
1105
1106 {
1107 struct cfg80211_internal_bss tmp = {}, *res;
1108 struct cfg80211_bss_ies *ies;
1109 struct ieee80211_channel *channel;
1110 bool signal_valid;
1111 size_t ielen = len - offsetof(struct ieee80211_mgmt,
1112 u.probe_resp.variable);
1113 int bss_type;
1114
1115 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1116 offsetof(struct ieee80211_mgmt, u.beacon.variable));
1117
1118 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1119
1120 if (WARN_ON(!mgmt))
1121 return NULL;
1122
1123 if (WARN_ON(!wiphy))
1124 return NULL;
1125
1126 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1127 (data->signal < 0 || data->signal > 100)))
1128 return NULL;
1129
1130 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1131 return NULL;
1132
1133 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1134 ielen, data->chan);
1135 if (!channel)
1136 return NULL;
1137
1138 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1139 if (!ies)
1140 return NULL;
1141 ies->len = ielen;
1142 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1143 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1144 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1145
1146 if (ieee80211_is_probe_resp(mgmt->frame_control))
1147 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1148 else
1149 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1150 rcu_assign_pointer(tmp.pub.ies, ies);
1151
1152 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1153 tmp.pub.channel = channel;
1154 tmp.pub.scan_width = data->scan_width;
1155 tmp.pub.signal = data->signal;
1156 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1157 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1158 tmp.ts_boottime = data->boottime_ns;
1159 tmp.parent_tsf = data->parent_tsf;
1160 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1161
1162 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1163 wiphy->max_adj_channel_rssi_comp;
1164 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1165 if (!res)
1166 return NULL;
1167
1168 if (channel->band == NL80211_BAND_60GHZ) {
1169 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1170 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1171 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1172 regulatory_hint_found_beacon(wiphy, channel, gfp);
1173 } else {
1174 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1175 regulatory_hint_found_beacon(wiphy, channel, gfp);
1176 }
1177
1178 trace_cfg80211_return_bss(&res->pub);
1179 /* cfg80211_bss_update gives us a referenced result */
1180 return &res->pub;
1181 }
1182 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1183
1184 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1185 {
1186 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1187 struct cfg80211_internal_bss *bss;
1188
1189 if (!pub)
1190 return;
1191
1192 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1193
1194 spin_lock_bh(&rdev->bss_lock);
1195 bss_ref_get(rdev, bss);
1196 spin_unlock_bh(&rdev->bss_lock);
1197 }
1198 EXPORT_SYMBOL(cfg80211_ref_bss);
1199
1200 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1201 {
1202 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1203 struct cfg80211_internal_bss *bss;
1204
1205 if (!pub)
1206 return;
1207
1208 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1209
1210 spin_lock_bh(&rdev->bss_lock);
1211 bss_ref_put(rdev, bss);
1212 spin_unlock_bh(&rdev->bss_lock);
1213 }
1214 EXPORT_SYMBOL(cfg80211_put_bss);
1215
1216 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1217 {
1218 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1219 struct cfg80211_internal_bss *bss;
1220
1221 if (WARN_ON(!pub))
1222 return;
1223
1224 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1225
1226 spin_lock_bh(&rdev->bss_lock);
1227 if (!list_empty(&bss->list)) {
1228 if (__cfg80211_unlink_bss(rdev, bss))
1229 rdev->bss_generation++;
1230 }
1231 spin_unlock_bh(&rdev->bss_lock);
1232 }
1233 EXPORT_SYMBOL(cfg80211_unlink_bss);
1234
1235 #ifdef CONFIG_CFG80211_WEXT
1236 static struct cfg80211_registered_device *
1237 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1238 {
1239 struct cfg80211_registered_device *rdev;
1240 struct net_device *dev;
1241
1242 ASSERT_RTNL();
1243
1244 dev = dev_get_by_index(net, ifindex);
1245 if (!dev)
1246 return ERR_PTR(-ENODEV);
1247 if (dev->ieee80211_ptr)
1248 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1249 else
1250 rdev = ERR_PTR(-ENODEV);
1251 dev_put(dev);
1252 return rdev;
1253 }
1254
1255 int cfg80211_wext_siwscan(struct net_device *dev,
1256 struct iw_request_info *info,
1257 union iwreq_data *wrqu, char *extra)
1258 {
1259 struct cfg80211_registered_device *rdev;
1260 struct wiphy *wiphy;
1261 struct iw_scan_req *wreq = NULL;
1262 struct cfg80211_scan_request *creq = NULL;
1263 int i, err, n_channels = 0;
1264 enum nl80211_band band;
1265
1266 if (!netif_running(dev))
1267 return -ENETDOWN;
1268
1269 if (wrqu->data.length == sizeof(struct iw_scan_req))
1270 wreq = (struct iw_scan_req *)extra;
1271
1272 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1273
1274 if (IS_ERR(rdev))
1275 return PTR_ERR(rdev);
1276
1277 if (rdev->scan_req || rdev->scan_msg) {
1278 err = -EBUSY;
1279 goto out;
1280 }
1281
1282 wiphy = &rdev->wiphy;
1283
1284 /* Determine number of channels, needed to allocate creq */
1285 if (wreq && wreq->num_channels)
1286 n_channels = wreq->num_channels;
1287 else
1288 n_channels = ieee80211_get_num_supported_channels(wiphy);
1289
1290 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1291 n_channels * sizeof(void *),
1292 GFP_ATOMIC);
1293 if (!creq) {
1294 err = -ENOMEM;
1295 goto out;
1296 }
1297
1298 creq->wiphy = wiphy;
1299 creq->wdev = dev->ieee80211_ptr;
1300 /* SSIDs come after channels */
1301 creq->ssids = (void *)&creq->channels[n_channels];
1302 creq->n_channels = n_channels;
1303 creq->n_ssids = 1;
1304 creq->scan_start = jiffies;
1305
1306 /* translate "Scan on frequencies" request */
1307 i = 0;
1308 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1309 int j;
1310
1311 if (!wiphy->bands[band])
1312 continue;
1313
1314 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1315 /* ignore disabled channels */
1316 if (wiphy->bands[band]->channels[j].flags &
1317 IEEE80211_CHAN_DISABLED)
1318 continue;
1319
1320 /* If we have a wireless request structure and the
1321 * wireless request specifies frequencies, then search
1322 * for the matching hardware channel.
1323 */
1324 if (wreq && wreq->num_channels) {
1325 int k;
1326 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1327 for (k = 0; k < wreq->num_channels; k++) {
1328 struct iw_freq *freq =
1329 &wreq->channel_list[k];
1330 int wext_freq =
1331 cfg80211_wext_freq(freq);
1332
1333 if (wext_freq == wiphy_freq)
1334 goto wext_freq_found;
1335 }
1336 goto wext_freq_not_found;
1337 }
1338
1339 wext_freq_found:
1340 creq->channels[i] = &wiphy->bands[band]->channels[j];
1341 i++;
1342 wext_freq_not_found: ;
1343 }
1344 }
1345 /* No channels found? */
1346 if (!i) {
1347 err = -EINVAL;
1348 goto out;
1349 }
1350
1351 /* Set real number of channels specified in creq->channels[] */
1352 creq->n_channels = i;
1353
1354 /* translate "Scan for SSID" request */
1355 if (wreq) {
1356 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1357 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1358 err = -EINVAL;
1359 goto out;
1360 }
1361 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1362 creq->ssids[0].ssid_len = wreq->essid_len;
1363 }
1364 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1365 creq->n_ssids = 0;
1366 }
1367
1368 for (i = 0; i < NUM_NL80211_BANDS; i++)
1369 if (wiphy->bands[i])
1370 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1371
1372 eth_broadcast_addr(creq->bssid);
1373
1374 rdev->scan_req = creq;
1375 err = rdev_scan(rdev, creq);
1376 if (err) {
1377 rdev->scan_req = NULL;
1378 /* creq will be freed below */
1379 } else {
1380 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1381 /* creq now owned by driver */
1382 creq = NULL;
1383 dev_hold(dev);
1384 }
1385 out:
1386 kfree(creq);
1387 return err;
1388 }
1389 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1390
1391 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1392 const struct cfg80211_bss_ies *ies,
1393 char *current_ev, char *end_buf)
1394 {
1395 const u8 *pos, *end, *next;
1396 struct iw_event iwe;
1397
1398 if (!ies)
1399 return current_ev;
1400
1401 /*
1402 * If needed, fragment the IEs buffer (at IE boundaries) into short
1403 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1404 */
1405 pos = ies->data;
1406 end = pos + ies->len;
1407
1408 while (end - pos > IW_GENERIC_IE_MAX) {
1409 next = pos + 2 + pos[1];
1410 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1411 next = next + 2 + next[1];
1412
1413 memset(&iwe, 0, sizeof(iwe));
1414 iwe.cmd = IWEVGENIE;
1415 iwe.u.data.length = next - pos;
1416 current_ev = iwe_stream_add_point_check(info, current_ev,
1417 end_buf, &iwe,
1418 (void *)pos);
1419 if (IS_ERR(current_ev))
1420 return current_ev;
1421 pos = next;
1422 }
1423
1424 if (end > pos) {
1425 memset(&iwe, 0, sizeof(iwe));
1426 iwe.cmd = IWEVGENIE;
1427 iwe.u.data.length = end - pos;
1428 current_ev = iwe_stream_add_point_check(info, current_ev,
1429 end_buf, &iwe,
1430 (void *)pos);
1431 if (IS_ERR(current_ev))
1432 return current_ev;
1433 }
1434
1435 return current_ev;
1436 }
1437
1438 static char *
1439 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1440 struct cfg80211_internal_bss *bss, char *current_ev,
1441 char *end_buf)
1442 {
1443 const struct cfg80211_bss_ies *ies;
1444 struct iw_event iwe;
1445 const u8 *ie;
1446 u8 buf[50];
1447 u8 *cfg, *p, *tmp;
1448 int rem, i, sig;
1449 bool ismesh = false;
1450
1451 memset(&iwe, 0, sizeof(iwe));
1452 iwe.cmd = SIOCGIWAP;
1453 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1454 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1455 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1456 IW_EV_ADDR_LEN);
1457 if (IS_ERR(current_ev))
1458 return current_ev;
1459
1460 memset(&iwe, 0, sizeof(iwe));
1461 iwe.cmd = SIOCGIWFREQ;
1462 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1463 iwe.u.freq.e = 0;
1464 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1465 IW_EV_FREQ_LEN);
1466 if (IS_ERR(current_ev))
1467 return current_ev;
1468
1469 memset(&iwe, 0, sizeof(iwe));
1470 iwe.cmd = SIOCGIWFREQ;
1471 iwe.u.freq.m = bss->pub.channel->center_freq;
1472 iwe.u.freq.e = 6;
1473 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1474 IW_EV_FREQ_LEN);
1475 if (IS_ERR(current_ev))
1476 return current_ev;
1477
1478 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1479 memset(&iwe, 0, sizeof(iwe));
1480 iwe.cmd = IWEVQUAL;
1481 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1482 IW_QUAL_NOISE_INVALID |
1483 IW_QUAL_QUAL_UPDATED;
1484 switch (wiphy->signal_type) {
1485 case CFG80211_SIGNAL_TYPE_MBM:
1486 sig = bss->pub.signal / 100;
1487 iwe.u.qual.level = sig;
1488 iwe.u.qual.updated |= IW_QUAL_DBM;
1489 if (sig < -110) /* rather bad */
1490 sig = -110;
1491 else if (sig > -40) /* perfect */
1492 sig = -40;
1493 /* will give a range of 0 .. 70 */
1494 iwe.u.qual.qual = sig + 110;
1495 break;
1496 case CFG80211_SIGNAL_TYPE_UNSPEC:
1497 iwe.u.qual.level = bss->pub.signal;
1498 /* will give range 0 .. 100 */
1499 iwe.u.qual.qual = bss->pub.signal;
1500 break;
1501 default:
1502 /* not reached */
1503 break;
1504 }
1505 current_ev = iwe_stream_add_event_check(info, current_ev,
1506 end_buf, &iwe,
1507 IW_EV_QUAL_LEN);
1508 if (IS_ERR(current_ev))
1509 return current_ev;
1510 }
1511
1512 memset(&iwe, 0, sizeof(iwe));
1513 iwe.cmd = SIOCGIWENCODE;
1514 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1515 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1516 else
1517 iwe.u.data.flags = IW_ENCODE_DISABLED;
1518 iwe.u.data.length = 0;
1519 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1520 &iwe, "");
1521 if (IS_ERR(current_ev))
1522 return current_ev;
1523
1524 rcu_read_lock();
1525 ies = rcu_dereference(bss->pub.ies);
1526 rem = ies->len;
1527 ie = ies->data;
1528
1529 while (rem >= 2) {
1530 /* invalid data */
1531 if (ie[1] > rem - 2)
1532 break;
1533
1534 switch (ie[0]) {
1535 case WLAN_EID_SSID:
1536 memset(&iwe, 0, sizeof(iwe));
1537 iwe.cmd = SIOCGIWESSID;
1538 iwe.u.data.length = ie[1];
1539 iwe.u.data.flags = 1;
1540 current_ev = iwe_stream_add_point_check(info,
1541 current_ev,
1542 end_buf, &iwe,
1543 (u8 *)ie + 2);
1544 if (IS_ERR(current_ev))
1545 goto unlock;
1546 break;
1547 case WLAN_EID_MESH_ID:
1548 memset(&iwe, 0, sizeof(iwe));
1549 iwe.cmd = SIOCGIWESSID;
1550 iwe.u.data.length = ie[1];
1551 iwe.u.data.flags = 1;
1552 current_ev = iwe_stream_add_point_check(info,
1553 current_ev,
1554 end_buf, &iwe,
1555 (u8 *)ie + 2);
1556 if (IS_ERR(current_ev))
1557 goto unlock;
1558 break;
1559 case WLAN_EID_MESH_CONFIG:
1560 ismesh = true;
1561 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1562 break;
1563 cfg = (u8 *)ie + 2;
1564 memset(&iwe, 0, sizeof(iwe));
1565 iwe.cmd = IWEVCUSTOM;
1566 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1567 "0x%02X", cfg[0]);
1568 iwe.u.data.length = strlen(buf);
1569 current_ev = iwe_stream_add_point_check(info,
1570 current_ev,
1571 end_buf,
1572 &iwe, buf);
1573 if (IS_ERR(current_ev))
1574 goto unlock;
1575 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1576 cfg[1]);
1577 iwe.u.data.length = strlen(buf);
1578 current_ev = iwe_stream_add_point_check(info,
1579 current_ev,
1580 end_buf,
1581 &iwe, buf);
1582 if (IS_ERR(current_ev))
1583 goto unlock;
1584 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1585 cfg[2]);
1586 iwe.u.data.length = strlen(buf);
1587 current_ev = iwe_stream_add_point_check(info,
1588 current_ev,
1589 end_buf,
1590 &iwe, buf);
1591 if (IS_ERR(current_ev))
1592 goto unlock;
1593 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1594 iwe.u.data.length = strlen(buf);
1595 current_ev = iwe_stream_add_point_check(info,
1596 current_ev,
1597 end_buf,
1598 &iwe, buf);
1599 if (IS_ERR(current_ev))
1600 goto unlock;
1601 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1602 iwe.u.data.length = strlen(buf);
1603 current_ev = iwe_stream_add_point_check(info,
1604 current_ev,
1605 end_buf,
1606 &iwe, buf);
1607 if (IS_ERR(current_ev))
1608 goto unlock;
1609 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1610 iwe.u.data.length = strlen(buf);
1611 current_ev = iwe_stream_add_point_check(info,
1612 current_ev,
1613 end_buf,
1614 &iwe, buf);
1615 if (IS_ERR(current_ev))
1616 goto unlock;
1617 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1618 iwe.u.data.length = strlen(buf);
1619 current_ev = iwe_stream_add_point_check(info,
1620 current_ev,
1621 end_buf,
1622 &iwe, buf);
1623 if (IS_ERR(current_ev))
1624 goto unlock;
1625 break;
1626 case WLAN_EID_SUPP_RATES:
1627 case WLAN_EID_EXT_SUPP_RATES:
1628 /* display all supported rates in readable format */
1629 p = current_ev + iwe_stream_lcp_len(info);
1630
1631 memset(&iwe, 0, sizeof(iwe));
1632 iwe.cmd = SIOCGIWRATE;
1633 /* Those two flags are ignored... */
1634 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1635
1636 for (i = 0; i < ie[1]; i++) {
1637 iwe.u.bitrate.value =
1638 ((ie[i + 2] & 0x7f) * 500000);
1639 tmp = p;
1640 p = iwe_stream_add_value(info, current_ev, p,
1641 end_buf, &iwe,
1642 IW_EV_PARAM_LEN);
1643 if (p == tmp) {
1644 current_ev = ERR_PTR(-E2BIG);
1645 goto unlock;
1646 }
1647 }
1648 current_ev = p;
1649 break;
1650 }
1651 rem -= ie[1] + 2;
1652 ie += ie[1] + 2;
1653 }
1654
1655 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1656 ismesh) {
1657 memset(&iwe, 0, sizeof(iwe));
1658 iwe.cmd = SIOCGIWMODE;
1659 if (ismesh)
1660 iwe.u.mode = IW_MODE_MESH;
1661 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1662 iwe.u.mode = IW_MODE_MASTER;
1663 else
1664 iwe.u.mode = IW_MODE_ADHOC;
1665 current_ev = iwe_stream_add_event_check(info, current_ev,
1666 end_buf, &iwe,
1667 IW_EV_UINT_LEN);
1668 if (IS_ERR(current_ev))
1669 goto unlock;
1670 }
1671
1672 memset(&iwe, 0, sizeof(iwe));
1673 iwe.cmd = IWEVCUSTOM;
1674 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1675 iwe.u.data.length = strlen(buf);
1676 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1677 &iwe, buf);
1678 if (IS_ERR(current_ev))
1679 goto unlock;
1680 memset(&iwe, 0, sizeof(iwe));
1681 iwe.cmd = IWEVCUSTOM;
1682 sprintf(buf, " Last beacon: %ums ago",
1683 elapsed_jiffies_msecs(bss->ts));
1684 iwe.u.data.length = strlen(buf);
1685 current_ev = iwe_stream_add_point_check(info, current_ev,
1686 end_buf, &iwe, buf);
1687 if (IS_ERR(current_ev))
1688 goto unlock;
1689
1690 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1691
1692 unlock:
1693 rcu_read_unlock();
1694 return current_ev;
1695 }
1696
1697
1698 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1699 struct iw_request_info *info,
1700 char *buf, size_t len)
1701 {
1702 char *current_ev = buf;
1703 char *end_buf = buf + len;
1704 struct cfg80211_internal_bss *bss;
1705 int err = 0;
1706
1707 spin_lock_bh(&rdev->bss_lock);
1708 cfg80211_bss_expire(rdev);
1709
1710 list_for_each_entry(bss, &rdev->bss_list, list) {
1711 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1712 err = -E2BIG;
1713 break;
1714 }
1715 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1716 current_ev, end_buf);
1717 if (IS_ERR(current_ev)) {
1718 err = PTR_ERR(current_ev);
1719 break;
1720 }
1721 }
1722 spin_unlock_bh(&rdev->bss_lock);
1723
1724 if (err)
1725 return err;
1726 return current_ev - buf;
1727 }
1728
1729
1730 int cfg80211_wext_giwscan(struct net_device *dev,
1731 struct iw_request_info *info,
1732 struct iw_point *data, char *extra)
1733 {
1734 struct cfg80211_registered_device *rdev;
1735 int res;
1736
1737 if (!netif_running(dev))
1738 return -ENETDOWN;
1739
1740 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1741
1742 if (IS_ERR(rdev))
1743 return PTR_ERR(rdev);
1744
1745 if (rdev->scan_req || rdev->scan_msg)
1746 return -EAGAIN;
1747
1748 res = ieee80211_scan_results(rdev, info, extra, data->length);
1749 data->length = 0;
1750 if (res >= 0) {
1751 data->length = res;
1752 res = 0;
1753 }
1754
1755 return res;
1756 }
1757 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1758 #endif
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