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Revert "ALSA: hda: Flush interrupts on disabling"
[linux/fpc-iii.git] / net / wireless / scan.c
blobc60be11b5e08bf76c14c0b75b42a12ab4b0c2ec0
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_result(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_result(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_results(rdev, request->dev);
325 }
326
327 rtnl_unlock();
328 }
329
330 void cfg80211_sched_scan_results(struct wiphy *wiphy)
331 {
332 trace_cfg80211_sched_scan_results(wiphy);
333 /* ignore if we're not scanning */
334
335 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
336 queue_work(cfg80211_wq,
337 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
338 }
339 EXPORT_SYMBOL(cfg80211_sched_scan_results);
340
341 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
342 {
343 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
344
345 ASSERT_RTNL();
346
347 trace_cfg80211_sched_scan_stopped(wiphy);
348
349 __cfg80211_stop_sched_scan(rdev, true);
350 }
351 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
352
353 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
354 {
355 rtnl_lock();
356 cfg80211_sched_scan_stopped_rtnl(wiphy);
357 rtnl_unlock();
358 }
359 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
360
361 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
362 bool driver_initiated)
363 {
364 struct cfg80211_sched_scan_request *sched_scan_req;
365 struct net_device *dev;
366
367 ASSERT_RTNL();
368
369 if (!rdev->sched_scan_req)
370 return -ENOENT;
371
372 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
373 dev = sched_scan_req->dev;
374
375 if (!driver_initiated) {
376 int err = rdev_sched_scan_stop(rdev, dev);
377 if (err)
378 return err;
379 }
380
381 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
382
383 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
384 kfree_rcu(sched_scan_req, rcu_head);
385
386 return 0;
387 }
388
389 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
390 unsigned long age_secs)
391 {
392 struct cfg80211_internal_bss *bss;
393 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
394
395 spin_lock_bh(&rdev->bss_lock);
396 list_for_each_entry(bss, &rdev->bss_list, list)
397 bss->ts -= age_jiffies;
398 spin_unlock_bh(&rdev->bss_lock);
399 }
400
401 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
402 {
403 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
404 }
405
406 const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,
407 const u8 *match, int match_len,
408 int match_offset)
409 {
410 const struct element *elem;
411
412 /* match_offset can't be smaller than 2, unless match_len is
413 * zero, in which case match_offset must be zero as well.
414 */
415 if (WARN_ON((match_len && match_offset < 2) ||
416 (!match_len && match_offset)))
417 return NULL;
418
419 for_each_element_id(elem, eid, ies, len) {
420 if (elem->datalen >= match_offset - 2 + match_len &&
421 !memcmp(elem->data + match_offset - 2, match, match_len))
422 return (void *)elem;
423 }
424
425 return NULL;
426 }
427 EXPORT_SYMBOL(cfg80211_find_ie_match);
428
429 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
430 const u8 *ies, int len)
431 {
432 const u8 *ie;
433 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
434 int match_len = (oui_type < 0) ? 3 : sizeof(match);
435
436 if (WARN_ON(oui_type > 0xff))
437 return NULL;
438
439 ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
440 match, match_len, 2);
441
442 if (ie && (ie[1] < 4))
443 return NULL;
444
445 return ie;
446 }
447 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
448
449 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
450 const u8 *ssid, size_t ssid_len)
451 {
452 const struct cfg80211_bss_ies *ies;
453 const u8 *ssidie;
454
455 if (bssid && !ether_addr_equal(a->bssid, bssid))
456 return false;
457
458 if (!ssid)
459 return true;
460
461 ies = rcu_access_pointer(a->ies);
462 if (!ies)
463 return false;
464 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
465 if (!ssidie)
466 return false;
467 if (ssidie[1] != ssid_len)
468 return false;
469 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
470 }
471
472 /**
473 * enum bss_compare_mode - BSS compare mode
474 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
475 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
476 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
477 */
478 enum bss_compare_mode {
479 BSS_CMP_REGULAR,
480 BSS_CMP_HIDE_ZLEN,
481 BSS_CMP_HIDE_NUL,
482 };
483
484 static int cmp_bss(struct cfg80211_bss *a,
485 struct cfg80211_bss *b,
486 enum bss_compare_mode mode)
487 {
488 const struct cfg80211_bss_ies *a_ies, *b_ies;
489 const u8 *ie1 = NULL;
490 const u8 *ie2 = NULL;
491 int i, r;
492
493 if (a->channel != b->channel)
494 return b->channel->center_freq - a->channel->center_freq;
495
496 a_ies = rcu_access_pointer(a->ies);
497 if (!a_ies)
498 return -1;
499 b_ies = rcu_access_pointer(b->ies);
500 if (!b_ies)
501 return 1;
502
503 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
504 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
505 a_ies->data, a_ies->len);
506 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
507 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
508 b_ies->data, b_ies->len);
509 if (ie1 && ie2) {
510 int mesh_id_cmp;
511
512 if (ie1[1] == ie2[1])
513 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
514 else
515 mesh_id_cmp = ie2[1] - ie1[1];
516
517 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
518 a_ies->data, a_ies->len);
519 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
520 b_ies->data, b_ies->len);
521 if (ie1 && ie2) {
522 if (mesh_id_cmp)
523 return mesh_id_cmp;
524 if (ie1[1] != ie2[1])
525 return ie2[1] - ie1[1];
526 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
527 }
528 }
529
530 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
531 if (r)
532 return r;
533
534 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
535 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
536
537 if (!ie1 && !ie2)
538 return 0;
539
540 /*
541 * Note that with "hide_ssid", the function returns a match if
542 * the already-present BSS ("b") is a hidden SSID beacon for
543 * the new BSS ("a").
544 */
545
546 /* sort missing IE before (left of) present IE */
547 if (!ie1)
548 return -1;
549 if (!ie2)
550 return 1;
551
552 switch (mode) {
553 case BSS_CMP_HIDE_ZLEN:
554 /*
555 * In ZLEN mode we assume the BSS entry we're
556 * looking for has a zero-length SSID. So if
557 * the one we're looking at right now has that,
558 * return 0. Otherwise, return the difference
559 * in length, but since we're looking for the
560 * 0-length it's really equivalent to returning
561 * the length of the one we're looking at.
562 *
563 * No content comparison is needed as we assume
564 * the content length is zero.
565 */
566 return ie2[1];
567 case BSS_CMP_REGULAR:
568 default:
569 /* sort by length first, then by contents */
570 if (ie1[1] != ie2[1])
571 return ie2[1] - ie1[1];
572 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
573 case BSS_CMP_HIDE_NUL:
574 if (ie1[1] != ie2[1])
575 return ie2[1] - ie1[1];
576 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
577 for (i = 0; i < ie2[1]; i++)
578 if (ie2[i + 2])
579 return -1;
580 return 0;
581 }
582 }
583
584 static bool cfg80211_bss_type_match(u16 capability,
585 enum nl80211_band band,
586 enum ieee80211_bss_type bss_type)
587 {
588 bool ret = true;
589 u16 mask, val;
590
591 if (bss_type == IEEE80211_BSS_TYPE_ANY)
592 return ret;
593
594 if (band == NL80211_BAND_60GHZ) {
595 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
596 switch (bss_type) {
597 case IEEE80211_BSS_TYPE_ESS:
598 val = WLAN_CAPABILITY_DMG_TYPE_AP;
599 break;
600 case IEEE80211_BSS_TYPE_PBSS:
601 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
602 break;
603 case IEEE80211_BSS_TYPE_IBSS:
604 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
605 break;
606 default:
607 return false;
608 }
609 } else {
610 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
611 switch (bss_type) {
612 case IEEE80211_BSS_TYPE_ESS:
613 val = WLAN_CAPABILITY_ESS;
614 break;
615 case IEEE80211_BSS_TYPE_IBSS:
616 val = WLAN_CAPABILITY_IBSS;
617 break;
618 case IEEE80211_BSS_TYPE_MBSS:
619 val = 0;
620 break;
621 default:
622 return false;
623 }
624 }
625
626 ret = ((capability & mask) == val);
627 return ret;
628 }
629
630 /* Returned bss is reference counted and must be cleaned up appropriately. */
631 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
632 struct ieee80211_channel *channel,
633 const u8 *bssid,
634 const u8 *ssid, size_t ssid_len,
635 enum ieee80211_bss_type bss_type,
636 enum ieee80211_privacy privacy)
637 {
638 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
639 struct cfg80211_internal_bss *bss, *res = NULL;
640 unsigned long now = jiffies;
641 int bss_privacy;
642
643 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
644 privacy);
645
646 spin_lock_bh(&rdev->bss_lock);
647
648 list_for_each_entry(bss, &rdev->bss_list, list) {
649 if (!cfg80211_bss_type_match(bss->pub.capability,
650 bss->pub.channel->band, bss_type))
651 continue;
652
653 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
654 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
655 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
656 continue;
657 if (channel && bss->pub.channel != channel)
658 continue;
659 if (!is_valid_ether_addr(bss->pub.bssid))
660 continue;
661 /* Don't get expired BSS structs */
662 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
663 !atomic_read(&bss->hold))
664 continue;
665 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
666 res = bss;
667 bss_ref_get(rdev, res);
668 break;
669 }
670 }
671
672 spin_unlock_bh(&rdev->bss_lock);
673 if (!res)
674 return NULL;
675 trace_cfg80211_return_bss(&res->pub);
676 return &res->pub;
677 }
678 EXPORT_SYMBOL(cfg80211_get_bss);
679
680 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
681 struct cfg80211_internal_bss *bss)
682 {
683 struct rb_node **p = &rdev->bss_tree.rb_node;
684 struct rb_node *parent = NULL;
685 struct cfg80211_internal_bss *tbss;
686 int cmp;
687
688 while (*p) {
689 parent = *p;
690 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
691
692 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
693
694 if (WARN_ON(!cmp)) {
695 /* will sort of leak this BSS */
696 return;
697 }
698
699 if (cmp < 0)
700 p = &(*p)->rb_left;
701 else
702 p = &(*p)->rb_right;
703 }
704
705 rb_link_node(&bss->rbn, parent, p);
706 rb_insert_color(&bss->rbn, &rdev->bss_tree);
707 }
708
709 static struct cfg80211_internal_bss *
710 rb_find_bss(struct cfg80211_registered_device *rdev,
711 struct cfg80211_internal_bss *res,
712 enum bss_compare_mode mode)
713 {
714 struct rb_node *n = rdev->bss_tree.rb_node;
715 struct cfg80211_internal_bss *bss;
716 int r;
717
718 while (n) {
719 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
720 r = cmp_bss(&res->pub, &bss->pub, mode);
721
722 if (r == 0)
723 return bss;
724 else if (r < 0)
725 n = n->rb_left;
726 else
727 n = n->rb_right;
728 }
729
730 return NULL;
731 }
732
733 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
734 struct cfg80211_internal_bss *new)
735 {
736 const struct cfg80211_bss_ies *ies;
737 struct cfg80211_internal_bss *bss;
738 const u8 *ie;
739 int i, ssidlen;
740 u8 fold = 0;
741 u32 n_entries = 0;
742
743 ies = rcu_access_pointer(new->pub.beacon_ies);
744 if (WARN_ON(!ies))
745 return false;
746
747 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
748 if (!ie) {
749 /* nothing to do */
750 return true;
751 }
752
753 ssidlen = ie[1];
754 for (i = 0; i < ssidlen; i++)
755 fold |= ie[2 + i];
756
757 if (fold) {
758 /* not a hidden SSID */
759 return true;
760 }
761
762 /* This is the bad part ... */
763
764 list_for_each_entry(bss, &rdev->bss_list, list) {
765 /*
766 * we're iterating all the entries anyway, so take the
767 * opportunity to validate the list length accounting
768 */
769 n_entries++;
770
771 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
772 continue;
773 if (bss->pub.channel != new->pub.channel)
774 continue;
775 if (bss->pub.scan_width != new->pub.scan_width)
776 continue;
777 if (rcu_access_pointer(bss->pub.beacon_ies))
778 continue;
779 ies = rcu_access_pointer(bss->pub.ies);
780 if (!ies)
781 continue;
782 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
783 if (!ie)
784 continue;
785 if (ssidlen && ie[1] != ssidlen)
786 continue;
787 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
788 continue;
789 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
790 list_del(&bss->hidden_list);
791 /* combine them */
792 list_add(&bss->hidden_list, &new->hidden_list);
793 bss->pub.hidden_beacon_bss = &new->pub;
794 new->refcount += bss->refcount;
795 rcu_assign_pointer(bss->pub.beacon_ies,
796 new->pub.beacon_ies);
797 }
798
799 WARN_ONCE(n_entries != rdev->bss_entries,
800 "rdev bss entries[%d]/list[len:%d] corruption\n",
801 rdev->bss_entries, n_entries);
802
803 return true;
804 }
805
806 /* Returned bss is reference counted and must be cleaned up appropriately. */
807 static struct cfg80211_internal_bss *
808 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
809 struct cfg80211_internal_bss *tmp,
810 bool signal_valid)
811 {
812 struct cfg80211_internal_bss *found = NULL;
813
814 if (WARN_ON(!tmp->pub.channel))
815 return NULL;
816
817 tmp->ts = jiffies;
818
819 spin_lock_bh(&rdev->bss_lock);
820
821 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
822 spin_unlock_bh(&rdev->bss_lock);
823 return NULL;
824 }
825
826 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
827
828 if (found) {
829 /* Update IEs */
830 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
831 const struct cfg80211_bss_ies *old;
832
833 old = rcu_access_pointer(found->pub.proberesp_ies);
834
835 rcu_assign_pointer(found->pub.proberesp_ies,
836 tmp->pub.proberesp_ies);
837 /* Override possible earlier Beacon frame IEs */
838 rcu_assign_pointer(found->pub.ies,
839 tmp->pub.proberesp_ies);
840 if (old)
841 kfree_rcu((struct cfg80211_bss_ies *)old,
842 rcu_head);
843 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
844 const struct cfg80211_bss_ies *old;
845 struct cfg80211_internal_bss *bss;
846
847 if (found->pub.hidden_beacon_bss &&
848 !list_empty(&found->hidden_list)) {
849 const struct cfg80211_bss_ies *f;
850
851 /*
852 * The found BSS struct is one of the probe
853 * response members of a group, but we're
854 * receiving a beacon (beacon_ies in the tmp
855 * bss is used). This can only mean that the
856 * AP changed its beacon from not having an
857 * SSID to showing it, which is confusing so
858 * drop this information.
859 */
860
861 f = rcu_access_pointer(tmp->pub.beacon_ies);
862 kfree_rcu((struct cfg80211_bss_ies *)f,
863 rcu_head);
864 goto drop;
865 }
866
867 old = rcu_access_pointer(found->pub.beacon_ies);
868
869 rcu_assign_pointer(found->pub.beacon_ies,
870 tmp->pub.beacon_ies);
871
872 /* Override IEs if they were from a beacon before */
873 if (old == rcu_access_pointer(found->pub.ies))
874 rcu_assign_pointer(found->pub.ies,
875 tmp->pub.beacon_ies);
876
877 /* Assign beacon IEs to all sub entries */
878 list_for_each_entry(bss, &found->hidden_list,
879 hidden_list) {
880 const struct cfg80211_bss_ies *ies;
881
882 ies = rcu_access_pointer(bss->pub.beacon_ies);
883 WARN_ON(ies != old);
884
885 rcu_assign_pointer(bss->pub.beacon_ies,
886 tmp->pub.beacon_ies);
887 }
888
889 if (old)
890 kfree_rcu((struct cfg80211_bss_ies *)old,
891 rcu_head);
892 }
893
894 found->pub.beacon_interval = tmp->pub.beacon_interval;
895 /*
896 * don't update the signal if beacon was heard on
897 * adjacent channel.
898 */
899 if (signal_valid)
900 found->pub.signal = tmp->pub.signal;
901 found->pub.capability = tmp->pub.capability;
902 found->ts = tmp->ts;
903 found->ts_boottime = tmp->ts_boottime;
904 found->parent_tsf = tmp->parent_tsf;
905 ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
906 } else {
907 struct cfg80211_internal_bss *new;
908 struct cfg80211_internal_bss *hidden;
909 struct cfg80211_bss_ies *ies;
910
911 /*
912 * create a copy -- the "res" variable that is passed in
913 * is allocated on the stack since it's not needed in the
914 * more common case of an update
915 */
916 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
917 GFP_ATOMIC);
918 if (!new) {
919 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
920 if (ies)
921 kfree_rcu(ies, rcu_head);
922 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
923 if (ies)
924 kfree_rcu(ies, rcu_head);
925 goto drop;
926 }
927 memcpy(new, tmp, sizeof(*new));
928 new->refcount = 1;
929 INIT_LIST_HEAD(&new->hidden_list);
930
931 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
932 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
933 if (!hidden)
934 hidden = rb_find_bss(rdev, tmp,
935 BSS_CMP_HIDE_NUL);
936 if (hidden) {
937 new->pub.hidden_beacon_bss = &hidden->pub;
938 list_add(&new->hidden_list,
939 &hidden->hidden_list);
940 hidden->refcount++;
941 rcu_assign_pointer(new->pub.beacon_ies,
942 hidden->pub.beacon_ies);
943 }
944 } else {
945 /*
946 * Ok so we found a beacon, and don't have an entry. If
947 * it's a beacon with hidden SSID, we might be in for an
948 * expensive search for any probe responses that should
949 * be grouped with this beacon for updates ...
950 */
951 if (!cfg80211_combine_bsses(rdev, new)) {
952 kfree(new);
953 goto drop;
954 }
955 }
956
957 if (rdev->bss_entries >= bss_entries_limit &&
958 !cfg80211_bss_expire_oldest(rdev)) {
959 kfree(new);
960 goto drop;
961 }
962
963 list_add_tail(&new->list, &rdev->bss_list);
964 rdev->bss_entries++;
965 rb_insert_bss(rdev, new);
966 found = new;
967 }
968
969 rdev->bss_generation++;
970 bss_ref_get(rdev, found);
971 spin_unlock_bh(&rdev->bss_lock);
972
973 return found;
974 drop:
975 spin_unlock_bh(&rdev->bss_lock);
976 return NULL;
977 }
978
979 /*
980 * Update RX channel information based on the available frame payload
981 * information. This is mainly for the 2.4 GHz band where frames can be received
982 * from neighboring channels and the Beacon frames use the DSSS Parameter Set
983 * element to indicate the current (transmitting) channel, but this might also
984 * be needed on other bands if RX frequency does not match with the actual
985 * operating channel of a BSS.
986 */
987 static struct ieee80211_channel *
988 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
989 struct ieee80211_channel *channel,
990 enum nl80211_bss_scan_width scan_width)
991 {
992 const u8 *tmp;
993 u32 freq;
994 int channel_number = -1;
995 struct ieee80211_channel *alt_channel;
996
997 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
998 if (tmp && tmp[1] == 1) {
999 channel_number = tmp[2];
1000 } else {
1001 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
1002 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
1003 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
1004
1005 channel_number = htop->primary_chan;
1006 }
1007 }
1008
1009 if (channel_number < 0) {
1010 /* No channel information in frame payload */
1011 return channel;
1012 }
1013
1014 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
1015 alt_channel = ieee80211_get_channel(wiphy, freq);
1016 if (!alt_channel) {
1017 if (channel->band == NL80211_BAND_2GHZ) {
1018 /*
1019 * Better not allow unexpected channels when that could
1020 * be going beyond the 1-11 range (e.g., discovering
1021 * BSS on channel 12 when radio is configured for
1022 * channel 11.
1023 */
1024 return NULL;
1025 }
1026
1027 /* No match for the payload channel number - ignore it */
1028 return channel;
1029 }
1030
1031 if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1032 scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1033 /*
1034 * Ignore channel number in 5 and 10 MHz channels where there
1035 * may not be an n:1 or 1:n mapping between frequencies and
1036 * channel numbers.
1037 */
1038 return channel;
1039 }
1040
1041 /*
1042 * Use the channel determined through the payload channel number
1043 * instead of the RX channel reported by the driver.
1044 */
1045 if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1046 return NULL;
1047 return alt_channel;
1048 }
1049
1050 /* Returned bss is reference counted and must be cleaned up appropriately. */
1051 struct cfg80211_bss *
1052 cfg80211_inform_bss_data(struct wiphy *wiphy,
1053 struct cfg80211_inform_bss *data,
1054 enum cfg80211_bss_frame_type ftype,
1055 const u8 *bssid, u64 tsf, u16 capability,
1056 u16 beacon_interval, const u8 *ie, size_t ielen,
1057 gfp_t gfp)
1058 {
1059 struct cfg80211_bss_ies *ies;
1060 struct ieee80211_channel *channel;
1061 struct cfg80211_internal_bss tmp = {}, *res;
1062 int bss_type;
1063 bool signal_valid;
1064
1065 if (WARN_ON(!wiphy))
1066 return NULL;
1067
1068 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1069 (data->signal < 0 || data->signal > 100)))
1070 return NULL;
1071
1072 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1073 data->scan_width);
1074 if (!channel)
1075 return NULL;
1076
1077 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1078 tmp.pub.channel = channel;
1079 tmp.pub.scan_width = data->scan_width;
1080 tmp.pub.signal = data->signal;
1081 tmp.pub.beacon_interval = beacon_interval;
1082 tmp.pub.capability = capability;
1083 tmp.ts_boottime = data->boottime_ns;
1084
1085 /*
1086 * If we do not know here whether the IEs are from a Beacon or Probe
1087 * Response frame, we need to pick one of the options and only use it
1088 * with the driver that does not provide the full Beacon/Probe Response
1089 * frame. Use Beacon frame pointer to avoid indicating that this should
1090 * override the IEs pointer should we have received an earlier
1091 * indication of Probe Response data.
1092 */
1093 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1094 if (!ies)
1095 return NULL;
1096 ies->len = ielen;
1097 ies->tsf = tsf;
1098 ies->from_beacon = false;
1099 memcpy(ies->data, ie, ielen);
1100
1101 switch (ftype) {
1102 case CFG80211_BSS_FTYPE_BEACON:
1103 ies->from_beacon = true;
1104 /* fall through to assign */
1105 case CFG80211_BSS_FTYPE_UNKNOWN:
1106 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1107 break;
1108 case CFG80211_BSS_FTYPE_PRESP:
1109 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1110 break;
1111 }
1112 rcu_assign_pointer(tmp.pub.ies, ies);
1113
1114 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1115 wiphy->max_adj_channel_rssi_comp;
1116 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1117 if (!res)
1118 return NULL;
1119
1120 if (channel->band == NL80211_BAND_60GHZ) {
1121 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1122 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1123 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1124 regulatory_hint_found_beacon(wiphy, channel, gfp);
1125 } else {
1126 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1127 regulatory_hint_found_beacon(wiphy, channel, gfp);
1128 }
1129
1130 trace_cfg80211_return_bss(&res->pub);
1131 /* cfg80211_bss_update gives us a referenced result */
1132 return &res->pub;
1133 }
1134 EXPORT_SYMBOL(cfg80211_inform_bss_data);
1135
1136 /* cfg80211_inform_bss_width_frame helper */
1137 struct cfg80211_bss *
1138 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1139 struct cfg80211_inform_bss *data,
1140 struct ieee80211_mgmt *mgmt, size_t len,
1141 gfp_t gfp)
1142
1143 {
1144 struct cfg80211_internal_bss tmp = {}, *res;
1145 struct cfg80211_bss_ies *ies;
1146 struct ieee80211_channel *channel;
1147 bool signal_valid;
1148 size_t ielen = len - offsetof(struct ieee80211_mgmt,
1149 u.probe_resp.variable);
1150 int bss_type;
1151
1152 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1153 offsetof(struct ieee80211_mgmt, u.beacon.variable));
1154
1155 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1156
1157 if (WARN_ON(!mgmt))
1158 return NULL;
1159
1160 if (WARN_ON(!wiphy))
1161 return NULL;
1162
1163 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1164 (data->signal < 0 || data->signal > 100)))
1165 return NULL;
1166
1167 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1168 return NULL;
1169
1170 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1171 ielen, data->chan, data->scan_width);
1172 if (!channel)
1173 return NULL;
1174
1175 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1176 if (!ies)
1177 return NULL;
1178 ies->len = ielen;
1179 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1180 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1181 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1182
1183 if (ieee80211_is_probe_resp(mgmt->frame_control))
1184 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1185 else
1186 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1187 rcu_assign_pointer(tmp.pub.ies, ies);
1188
1189 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1190 tmp.pub.channel = channel;
1191 tmp.pub.scan_width = data->scan_width;
1192 tmp.pub.signal = data->signal;
1193 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1194 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1195 tmp.ts_boottime = data->boottime_ns;
1196 tmp.parent_tsf = data->parent_tsf;
1197 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1198
1199 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1200 wiphy->max_adj_channel_rssi_comp;
1201 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1202 if (!res)
1203 return NULL;
1204
1205 if (channel->band == NL80211_BAND_60GHZ) {
1206 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1207 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1208 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1209 regulatory_hint_found_beacon(wiphy, channel, gfp);
1210 } else {
1211 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1212 regulatory_hint_found_beacon(wiphy, channel, gfp);
1213 }
1214
1215 trace_cfg80211_return_bss(&res->pub);
1216 /* cfg80211_bss_update gives us a referenced result */
1217 return &res->pub;
1218 }
1219 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1220
1221 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1222 {
1223 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1224 struct cfg80211_internal_bss *bss;
1225
1226 if (!pub)
1227 return;
1228
1229 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1230
1231 spin_lock_bh(&rdev->bss_lock);
1232 bss_ref_get(rdev, bss);
1233 spin_unlock_bh(&rdev->bss_lock);
1234 }
1235 EXPORT_SYMBOL(cfg80211_ref_bss);
1236
1237 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1238 {
1239 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1240 struct cfg80211_internal_bss *bss;
1241
1242 if (!pub)
1243 return;
1244
1245 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1246
1247 spin_lock_bh(&rdev->bss_lock);
1248 bss_ref_put(rdev, bss);
1249 spin_unlock_bh(&rdev->bss_lock);
1250 }
1251 EXPORT_SYMBOL(cfg80211_put_bss);
1252
1253 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1254 {
1255 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1256 struct cfg80211_internal_bss *bss;
1257
1258 if (WARN_ON(!pub))
1259 return;
1260
1261 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1262
1263 spin_lock_bh(&rdev->bss_lock);
1264 if (!list_empty(&bss->list)) {
1265 if (__cfg80211_unlink_bss(rdev, bss))
1266 rdev->bss_generation++;
1267 }
1268 spin_unlock_bh(&rdev->bss_lock);
1269 }
1270 EXPORT_SYMBOL(cfg80211_unlink_bss);
1271
1272 #ifdef CONFIG_CFG80211_WEXT
1273 static struct cfg80211_registered_device *
1274 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1275 {
1276 struct cfg80211_registered_device *rdev;
1277 struct net_device *dev;
1278
1279 ASSERT_RTNL();
1280
1281 dev = dev_get_by_index(net, ifindex);
1282 if (!dev)
1283 return ERR_PTR(-ENODEV);
1284 if (dev->ieee80211_ptr)
1285 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1286 else
1287 rdev = ERR_PTR(-ENODEV);
1288 dev_put(dev);
1289 return rdev;
1290 }
1291
1292 int cfg80211_wext_siwscan(struct net_device *dev,
1293 struct iw_request_info *info,
1294 union iwreq_data *wrqu, char *extra)
1295 {
1296 struct cfg80211_registered_device *rdev;
1297 struct wiphy *wiphy;
1298 struct iw_scan_req *wreq = NULL;
1299 struct cfg80211_scan_request *creq = NULL;
1300 int i, err, n_channels = 0;
1301 enum nl80211_band band;
1302
1303 if (!netif_running(dev))
1304 return -ENETDOWN;
1305
1306 if (wrqu->data.length == sizeof(struct iw_scan_req))
1307 wreq = (struct iw_scan_req *)extra;
1308
1309 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1310
1311 if (IS_ERR(rdev))
1312 return PTR_ERR(rdev);
1313
1314 if (rdev->scan_req || rdev->scan_msg) {
1315 err = -EBUSY;
1316 goto out;
1317 }
1318
1319 wiphy = &rdev->wiphy;
1320
1321 /* Determine number of channels, needed to allocate creq */
1322 if (wreq && wreq->num_channels)
1323 n_channels = wreq->num_channels;
1324 else
1325 n_channels = ieee80211_get_num_supported_channels(wiphy);
1326
1327 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1328 n_channels * sizeof(void *),
1329 GFP_ATOMIC);
1330 if (!creq) {
1331 err = -ENOMEM;
1332 goto out;
1333 }
1334
1335 creq->wiphy = wiphy;
1336 creq->wdev = dev->ieee80211_ptr;
1337 /* SSIDs come after channels */
1338 creq->ssids = (void *)&creq->channels[n_channels];
1339 creq->n_channels = n_channels;
1340 creq->n_ssids = 1;
1341 creq->scan_start = jiffies;
1342
1343 /* translate "Scan on frequencies" request */
1344 i = 0;
1345 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1346 int j;
1347
1348 if (!wiphy->bands[band])
1349 continue;
1350
1351 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1352 /* ignore disabled channels */
1353 if (wiphy->bands[band]->channels[j].flags &
1354 IEEE80211_CHAN_DISABLED)
1355 continue;
1356
1357 /* If we have a wireless request structure and the
1358 * wireless request specifies frequencies, then search
1359 * for the matching hardware channel.
1360 */
1361 if (wreq && wreq->num_channels) {
1362 int k;
1363 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1364 for (k = 0; k < wreq->num_channels; k++) {
1365 struct iw_freq *freq =
1366 &wreq->channel_list[k];
1367 int wext_freq =
1368 cfg80211_wext_freq(freq);
1369
1370 if (wext_freq == wiphy_freq)
1371 goto wext_freq_found;
1372 }
1373 goto wext_freq_not_found;
1374 }
1375
1376 wext_freq_found:
1377 creq->channels[i] = &wiphy->bands[band]->channels[j];
1378 i++;
1379 wext_freq_not_found: ;
1380 }
1381 }
1382 /* No channels found? */
1383 if (!i) {
1384 err = -EINVAL;
1385 goto out;
1386 }
1387
1388 /* Set real number of channels specified in creq->channels[] */
1389 creq->n_channels = i;
1390
1391 /* translate "Scan for SSID" request */
1392 if (wreq) {
1393 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1394 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1395 err = -EINVAL;
1396 goto out;
1397 }
1398 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1399 creq->ssids[0].ssid_len = wreq->essid_len;
1400 }
1401 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1402 creq->n_ssids = 0;
1403 }
1404
1405 for (i = 0; i < NUM_NL80211_BANDS; i++)
1406 if (wiphy->bands[i])
1407 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1408
1409 eth_broadcast_addr(creq->bssid);
1410
1411 rdev->scan_req = creq;
1412 err = rdev_scan(rdev, creq);
1413 if (err) {
1414 rdev->scan_req = NULL;
1415 /* creq will be freed below */
1416 } else {
1417 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1418 /* creq now owned by driver */
1419 creq = NULL;
1420 dev_hold(dev);
1421 }
1422 out:
1423 kfree(creq);
1424 return err;
1425 }
1426 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1427
1428 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1429 const struct cfg80211_bss_ies *ies,
1430 char *current_ev, char *end_buf)
1431 {
1432 const u8 *pos, *end, *next;
1433 struct iw_event iwe;
1434
1435 if (!ies)
1436 return current_ev;
1437
1438 /*
1439 * If needed, fragment the IEs buffer (at IE boundaries) into short
1440 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1441 */
1442 pos = ies->data;
1443 end = pos + ies->len;
1444
1445 while (end - pos > IW_GENERIC_IE_MAX) {
1446 next = pos + 2 + pos[1];
1447 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1448 next = next + 2 + next[1];
1449
1450 memset(&iwe, 0, sizeof(iwe));
1451 iwe.cmd = IWEVGENIE;
1452 iwe.u.data.length = next - pos;
1453 current_ev = iwe_stream_add_point_check(info, current_ev,
1454 end_buf, &iwe,
1455 (void *)pos);
1456 if (IS_ERR(current_ev))
1457 return current_ev;
1458 pos = next;
1459 }
1460
1461 if (end > pos) {
1462 memset(&iwe, 0, sizeof(iwe));
1463 iwe.cmd = IWEVGENIE;
1464 iwe.u.data.length = end - pos;
1465 current_ev = iwe_stream_add_point_check(info, current_ev,
1466 end_buf, &iwe,
1467 (void *)pos);
1468 if (IS_ERR(current_ev))
1469 return current_ev;
1470 }
1471
1472 return current_ev;
1473 }
1474
1475 static char *
1476 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1477 struct cfg80211_internal_bss *bss, char *current_ev,
1478 char *end_buf)
1479 {
1480 const struct cfg80211_bss_ies *ies;
1481 struct iw_event iwe;
1482 const u8 *ie;
1483 u8 buf[50];
1484 u8 *cfg, *p, *tmp;
1485 int rem, i, sig;
1486 bool ismesh = false;
1487
1488 memset(&iwe, 0, sizeof(iwe));
1489 iwe.cmd = SIOCGIWAP;
1490 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1491 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1492 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1493 IW_EV_ADDR_LEN);
1494 if (IS_ERR(current_ev))
1495 return current_ev;
1496
1497 memset(&iwe, 0, sizeof(iwe));
1498 iwe.cmd = SIOCGIWFREQ;
1499 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1500 iwe.u.freq.e = 0;
1501 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1502 IW_EV_FREQ_LEN);
1503 if (IS_ERR(current_ev))
1504 return current_ev;
1505
1506 memset(&iwe, 0, sizeof(iwe));
1507 iwe.cmd = SIOCGIWFREQ;
1508 iwe.u.freq.m = bss->pub.channel->center_freq;
1509 iwe.u.freq.e = 6;
1510 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1511 IW_EV_FREQ_LEN);
1512 if (IS_ERR(current_ev))
1513 return current_ev;
1514
1515 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1516 memset(&iwe, 0, sizeof(iwe));
1517 iwe.cmd = IWEVQUAL;
1518 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1519 IW_QUAL_NOISE_INVALID |
1520 IW_QUAL_QUAL_UPDATED;
1521 switch (wiphy->signal_type) {
1522 case CFG80211_SIGNAL_TYPE_MBM:
1523 sig = bss->pub.signal / 100;
1524 iwe.u.qual.level = sig;
1525 iwe.u.qual.updated |= IW_QUAL_DBM;
1526 if (sig < -110) /* rather bad */
1527 sig = -110;
1528 else if (sig > -40) /* perfect */
1529 sig = -40;
1530 /* will give a range of 0 .. 70 */
1531 iwe.u.qual.qual = sig + 110;
1532 break;
1533 case CFG80211_SIGNAL_TYPE_UNSPEC:
1534 iwe.u.qual.level = bss->pub.signal;
1535 /* will give range 0 .. 100 */
1536 iwe.u.qual.qual = bss->pub.signal;
1537 break;
1538 default:
1539 /* not reached */
1540 break;
1541 }
1542 current_ev = iwe_stream_add_event_check(info, current_ev,
1543 end_buf, &iwe,
1544 IW_EV_QUAL_LEN);
1545 if (IS_ERR(current_ev))
1546 return current_ev;
1547 }
1548
1549 memset(&iwe, 0, sizeof(iwe));
1550 iwe.cmd = SIOCGIWENCODE;
1551 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1552 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1553 else
1554 iwe.u.data.flags = IW_ENCODE_DISABLED;
1555 iwe.u.data.length = 0;
1556 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1557 &iwe, "");
1558 if (IS_ERR(current_ev))
1559 return current_ev;
1560
1561 rcu_read_lock();
1562 ies = rcu_dereference(bss->pub.ies);
1563 rem = ies->len;
1564 ie = ies->data;
1565
1566 while (rem >= 2) {
1567 /* invalid data */
1568 if (ie[1] > rem - 2)
1569 break;
1570
1571 switch (ie[0]) {
1572 case WLAN_EID_SSID:
1573 memset(&iwe, 0, sizeof(iwe));
1574 iwe.cmd = SIOCGIWESSID;
1575 iwe.u.data.length = ie[1];
1576 iwe.u.data.flags = 1;
1577 current_ev = iwe_stream_add_point_check(info,
1578 current_ev,
1579 end_buf, &iwe,
1580 (u8 *)ie + 2);
1581 if (IS_ERR(current_ev))
1582 goto unlock;
1583 break;
1584 case WLAN_EID_MESH_ID:
1585 memset(&iwe, 0, sizeof(iwe));
1586 iwe.cmd = SIOCGIWESSID;
1587 iwe.u.data.length = ie[1];
1588 iwe.u.data.flags = 1;
1589 current_ev = iwe_stream_add_point_check(info,
1590 current_ev,
1591 end_buf, &iwe,
1592 (u8 *)ie + 2);
1593 if (IS_ERR(current_ev))
1594 goto unlock;
1595 break;
1596 case WLAN_EID_MESH_CONFIG:
1597 ismesh = true;
1598 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1599 break;
1600 cfg = (u8 *)ie + 2;
1601 memset(&iwe, 0, sizeof(iwe));
1602 iwe.cmd = IWEVCUSTOM;
1603 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1604 "0x%02X", cfg[0]);
1605 iwe.u.data.length = strlen(buf);
1606 current_ev = iwe_stream_add_point_check(info,
1607 current_ev,
1608 end_buf,
1609 &iwe, buf);
1610 if (IS_ERR(current_ev))
1611 goto unlock;
1612 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1613 cfg[1]);
1614 iwe.u.data.length = strlen(buf);
1615 current_ev = iwe_stream_add_point_check(info,
1616 current_ev,
1617 end_buf,
1618 &iwe, buf);
1619 if (IS_ERR(current_ev))
1620 goto unlock;
1621 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1622 cfg[2]);
1623 iwe.u.data.length = strlen(buf);
1624 current_ev = iwe_stream_add_point_check(info,
1625 current_ev,
1626 end_buf,
1627 &iwe, buf);
1628 if (IS_ERR(current_ev))
1629 goto unlock;
1630 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1631 iwe.u.data.length = strlen(buf);
1632 current_ev = iwe_stream_add_point_check(info,
1633 current_ev,
1634 end_buf,
1635 &iwe, buf);
1636 if (IS_ERR(current_ev))
1637 goto unlock;
1638 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1639 iwe.u.data.length = strlen(buf);
1640 current_ev = iwe_stream_add_point_check(info,
1641 current_ev,
1642 end_buf,
1643 &iwe, buf);
1644 if (IS_ERR(current_ev))
1645 goto unlock;
1646 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1647 iwe.u.data.length = strlen(buf);
1648 current_ev = iwe_stream_add_point_check(info,
1649 current_ev,
1650 end_buf,
1651 &iwe, buf);
1652 if (IS_ERR(current_ev))
1653 goto unlock;
1654 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1655 iwe.u.data.length = strlen(buf);
1656 current_ev = iwe_stream_add_point_check(info,
1657 current_ev,
1658 end_buf,
1659 &iwe, buf);
1660 if (IS_ERR(current_ev))
1661 goto unlock;
1662 break;
1663 case WLAN_EID_SUPP_RATES:
1664 case WLAN_EID_EXT_SUPP_RATES:
1665 /* display all supported rates in readable format */
1666 p = current_ev + iwe_stream_lcp_len(info);
1667
1668 memset(&iwe, 0, sizeof(iwe));
1669 iwe.cmd = SIOCGIWRATE;
1670 /* Those two flags are ignored... */
1671 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1672
1673 for (i = 0; i < ie[1]; i++) {
1674 iwe.u.bitrate.value =
1675 ((ie[i + 2] & 0x7f) * 500000);
1676 tmp = p;
1677 p = iwe_stream_add_value(info, current_ev, p,
1678 end_buf, &iwe,
1679 IW_EV_PARAM_LEN);
1680 if (p == tmp) {
1681 current_ev = ERR_PTR(-E2BIG);
1682 goto unlock;
1683 }
1684 }
1685 current_ev = p;
1686 break;
1687 }
1688 rem -= ie[1] + 2;
1689 ie += ie[1] + 2;
1690 }
1691
1692 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1693 ismesh) {
1694 memset(&iwe, 0, sizeof(iwe));
1695 iwe.cmd = SIOCGIWMODE;
1696 if (ismesh)
1697 iwe.u.mode = IW_MODE_MESH;
1698 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1699 iwe.u.mode = IW_MODE_MASTER;
1700 else
1701 iwe.u.mode = IW_MODE_ADHOC;
1702 current_ev = iwe_stream_add_event_check(info, current_ev,
1703 end_buf, &iwe,
1704 IW_EV_UINT_LEN);
1705 if (IS_ERR(current_ev))
1706 goto unlock;
1707 }
1708
1709 memset(&iwe, 0, sizeof(iwe));
1710 iwe.cmd = IWEVCUSTOM;
1711 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1712 iwe.u.data.length = strlen(buf);
1713 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1714 &iwe, buf);
1715 if (IS_ERR(current_ev))
1716 goto unlock;
1717 memset(&iwe, 0, sizeof(iwe));
1718 iwe.cmd = IWEVCUSTOM;
1719 sprintf(buf, " Last beacon: %ums ago",
1720 elapsed_jiffies_msecs(bss->ts));
1721 iwe.u.data.length = strlen(buf);
1722 current_ev = iwe_stream_add_point_check(info, current_ev,
1723 end_buf, &iwe, buf);
1724 if (IS_ERR(current_ev))
1725 goto unlock;
1726
1727 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1728
1729 unlock:
1730 rcu_read_unlock();
1731 return current_ev;
1732 }
1733
1734
1735 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1736 struct iw_request_info *info,
1737 char *buf, size_t len)
1738 {
1739 char *current_ev = buf;
1740 char *end_buf = buf + len;
1741 struct cfg80211_internal_bss *bss;
1742 int err = 0;
1743
1744 spin_lock_bh(&rdev->bss_lock);
1745 cfg80211_bss_expire(rdev);
1746
1747 list_for_each_entry(bss, &rdev->bss_list, list) {
1748 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1749 err = -E2BIG;
1750 break;
1751 }
1752 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1753 current_ev, end_buf);
1754 if (IS_ERR(current_ev)) {
1755 err = PTR_ERR(current_ev);
1756 break;
1757 }
1758 }
1759 spin_unlock_bh(&rdev->bss_lock);
1760
1761 if (err)
1762 return err;
1763 return current_ev - buf;
1764 }
1765
1766
1767 int cfg80211_wext_giwscan(struct net_device *dev,
1768 struct iw_request_info *info,
1769 struct iw_point *data, char *extra)
1770 {
1771 struct cfg80211_registered_device *rdev;
1772 int res;
1773
1774 if (!netif_running(dev))
1775 return -ENETDOWN;
1776
1777 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1778
1779 if (IS_ERR(rdev))
1780 return PTR_ERR(rdev);
1781
1782 if (rdev->scan_req || rdev->scan_msg)
1783 return -EAGAIN;
1784
1785 res = ieee80211_scan_results(rdev, info, extra, data->length);
1786 data->length = 0;
1787 if (res >= 0) {
1788 data->length = res;
1789 res = 0;
1790 }
1791
1792 return res;
1793 }
1794 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1795 #endif
Linux with added FPC-III support