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Merge 4.4.71 into android-4.4
[GitHub/exynos8895/android_kernel_samsung_universal8895.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 */
7 #include <linux/kernel.h>
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/netdevice.h>
11 #include <linux/wireless.h>
12 #include <linux/nl80211.h>
13 #include <linux/etherdevice.h>
14 #include <net/arp.h>
15 #include <net/cfg80211.h>
16 #include <net/cfg80211-wext.h>
17 #include <net/iw_handler.h>
18 #include "core.h"
19 #include "nl80211.h"
20 #include "wext-compat.h"
21 #include "rdev-ops.h"
22
23 /**
24 * DOC: BSS tree/list structure
25 *
26 * At the top level, the BSS list is kept in both a list in each
27 * registered device (@bss_list) as well as an RB-tree for faster
28 * lookup. In the RB-tree, entries can be looked up using their
29 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
30 * for other BSSes.
31 *
32 * Due to the possibility of hidden SSIDs, there's a second level
33 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
34 * The hidden_list connects all BSSes belonging to a single AP
35 * that has a hidden SSID, and connects beacon and probe response
36 * entries. For a probe response entry for a hidden SSID, the
37 * hidden_beacon_bss pointer points to the BSS struct holding the
38 * beacon's information.
39 *
40 * Reference counting is done for all these references except for
41 * the hidden_list, so that a beacon BSS struct that is otherwise
42 * not referenced has one reference for being on the bss_list and
43 * one for each probe response entry that points to it using the
44 * hidden_beacon_bss pointer. When a BSS struct that has such a
45 * pointer is get/put, the refcount update is also propagated to
46 * the referenced struct, this ensure that it cannot get removed
47 * while somebody is using the probe response version.
48 *
49 * Note that the hidden_beacon_bss pointer never changes, due to
50 * the reference counting. Therefore, no locking is needed for
51 * it.
52 *
53 * Also note that the hidden_beacon_bss pointer is only relevant
54 * if the driver uses something other than the IEs, e.g. private
55 * data stored stored in the BSS struct, since the beacon IEs are
56 * also linked into the probe response struct.
57 */
58
59 /*
60 * Limit the number of BSS entries stored in mac80211. Each one is
61 * a bit over 4k at most, so this limits to roughly 4-5M of memory.
62 * If somebody wants to really attack this though, they'd likely
63 * use small beacons, and only one type of frame, limiting each of
64 * the entries to a much smaller size (in order to generate more
65 * entries in total, so overhead is bigger.)
66 */
67 static int bss_entries_limit = 1000;
68 module_param(bss_entries_limit, int, 0644);
69 MODULE_PARM_DESC(bss_entries_limit,
70 "limit to number of scan BSS entries (per wiphy, default 1000)");
71
72 #define IEEE80211_SCAN_RESULT_EXPIRE (7 * HZ)
73
74 static void bss_free(struct cfg80211_internal_bss *bss)
75 {
76 struct cfg80211_bss_ies *ies;
77
78 if (WARN_ON(atomic_read(&bss->hold)))
79 return;
80
81 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
82 if (ies && !bss->pub.hidden_beacon_bss)
83 kfree_rcu(ies, rcu_head);
84 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
85 if (ies)
86 kfree_rcu(ies, rcu_head);
87
88 /*
89 * This happens when the module is removed, it doesn't
90 * really matter any more save for completeness
91 */
92 if (!list_empty(&bss->hidden_list))
93 list_del(&bss->hidden_list);
94
95 kfree(bss);
96 }
97
98 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
99 struct cfg80211_internal_bss *bss)
100 {
101 lockdep_assert_held(&rdev->bss_lock);
102
103 bss->refcount++;
104 if (bss->pub.hidden_beacon_bss) {
105 bss = container_of(bss->pub.hidden_beacon_bss,
106 struct cfg80211_internal_bss,
107 pub);
108 bss->refcount++;
109 }
110 }
111
112 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
113 struct cfg80211_internal_bss *bss)
114 {
115 lockdep_assert_held(&rdev->bss_lock);
116
117 if (bss->pub.hidden_beacon_bss) {
118 struct cfg80211_internal_bss *hbss;
119 hbss = container_of(bss->pub.hidden_beacon_bss,
120 struct cfg80211_internal_bss,
121 pub);
122 hbss->refcount--;
123 if (hbss->refcount == 0)
124 bss_free(hbss);
125 }
126 bss->refcount--;
127 if (bss->refcount == 0)
128 bss_free(bss);
129 }
130
131 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
132 struct cfg80211_internal_bss *bss)
133 {
134 lockdep_assert_held(&rdev->bss_lock);
135
136 if (!list_empty(&bss->hidden_list)) {
137 /*
138 * don't remove the beacon entry if it has
139 * probe responses associated with it
140 */
141 if (!bss->pub.hidden_beacon_bss)
142 return false;
143 /*
144 * if it's a probe response entry break its
145 * link to the other entries in the group
146 */
147 list_del_init(&bss->hidden_list);
148 }
149
150 list_del_init(&bss->list);
151 rb_erase(&bss->rbn, &rdev->bss_tree);
152 rdev->bss_entries--;
153 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
154 "rdev bss entries[%d]/list[empty:%d] corruption\n",
155 rdev->bss_entries, list_empty(&rdev->bss_list));
156 bss_ref_put(rdev, bss);
157 return true;
158 }
159
160 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
161 unsigned long expire_time)
162 {
163 struct cfg80211_internal_bss *bss, *tmp;
164 bool expired = false;
165
166 lockdep_assert_held(&rdev->bss_lock);
167
168 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
169 if (atomic_read(&bss->hold))
170 continue;
171 if (!time_after(expire_time, bss->ts))
172 continue;
173
174 if (__cfg80211_unlink_bss(rdev, bss))
175 expired = true;
176 }
177
178 if (expired)
179 rdev->bss_generation++;
180 }
181
182 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
183 {
184 struct cfg80211_internal_bss *bss, *oldest = NULL;
185 bool ret;
186
187 lockdep_assert_held(&rdev->bss_lock);
188
189 list_for_each_entry(bss, &rdev->bss_list, list) {
190 if (atomic_read(&bss->hold))
191 continue;
192
193 if (!list_empty(&bss->hidden_list) &&
194 !bss->pub.hidden_beacon_bss)
195 continue;
196
197 if (oldest && time_before(oldest->ts, bss->ts))
198 continue;
199 oldest = bss;
200 }
201
202 if (WARN_ON(!oldest))
203 return false;
204
205 /*
206 * The callers make sure to increase rdev->bss_generation if anything
207 * gets removed (and a new entry added), so there's no need to also do
208 * it here.
209 */
210
211 ret = __cfg80211_unlink_bss(rdev, oldest);
212 WARN_ON(!ret);
213 return ret;
214 }
215
216 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
217 bool send_message)
218 {
219 struct cfg80211_scan_request *request;
220 struct wireless_dev *wdev;
221 struct sk_buff *msg;
222 #ifdef CONFIG_CFG80211_WEXT
223 union iwreq_data wrqu;
224 #endif
225
226 ASSERT_RTNL();
227
228 if (rdev->scan_msg) {
229 nl80211_send_scan_result(rdev, rdev->scan_msg);
230 rdev->scan_msg = NULL;
231 return;
232 }
233
234 request = rdev->scan_req;
235 if (!request)
236 return;
237
238 wdev = request->wdev;
239
240 /*
241 * This must be before sending the other events!
242 * Otherwise, wpa_supplicant gets completely confused with
243 * wext events.
244 */
245 if (wdev->netdev)
246 cfg80211_sme_scan_done(wdev->netdev);
247
248 if (!request->aborted &&
249 request->flags & NL80211_SCAN_FLAG_FLUSH) {
250 /* flush entries from previous scans */
251 spin_lock_bh(&rdev->bss_lock);
252 __cfg80211_bss_expire(rdev, request->scan_start);
253 spin_unlock_bh(&rdev->bss_lock);
254 }
255
256 msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
257
258 #ifdef CONFIG_CFG80211_WEXT
259 if (wdev->netdev && !request->aborted) {
260 memset(&wrqu, 0, sizeof(wrqu));
261
262 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
263 }
264 #endif
265
266 if (wdev->netdev)
267 dev_put(wdev->netdev);
268
269 rdev->scan_req = NULL;
270 kfree(request);
271
272 if (!send_message)
273 rdev->scan_msg = msg;
274 else
275 nl80211_send_scan_result(rdev, msg);
276 }
277
278 void __cfg80211_scan_done(struct work_struct *wk)
279 {
280 struct cfg80211_registered_device *rdev;
281
282 rdev = container_of(wk, struct cfg80211_registered_device,
283 scan_done_wk);
284
285 rtnl_lock();
286 ___cfg80211_scan_done(rdev, true);
287 rtnl_unlock();
288 }
289
290 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
291 {
292 trace_cfg80211_scan_done(request, aborted);
293 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
294
295 request->aborted = aborted;
296 request->notified = true;
297 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
298 }
299 EXPORT_SYMBOL(cfg80211_scan_done);
300
301 void __cfg80211_sched_scan_results(struct work_struct *wk)
302 {
303 struct cfg80211_registered_device *rdev;
304 struct cfg80211_sched_scan_request *request;
305
306 rdev = container_of(wk, struct cfg80211_registered_device,
307 sched_scan_results_wk);
308
309 rtnl_lock();
310
311 request = rtnl_dereference(rdev->sched_scan_req);
312
313 /* we don't have sched_scan_req anymore if the scan is stopping */
314 if (request) {
315 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
316 /* flush entries from previous scans */
317 spin_lock_bh(&rdev->bss_lock);
318 __cfg80211_bss_expire(rdev, request->scan_start);
319 spin_unlock_bh(&rdev->bss_lock);
320 request->scan_start = jiffies;
321 }
322 nl80211_send_sched_scan_results(rdev, request->dev);
323 }
324
325 rtnl_unlock();
326 }
327
328 void cfg80211_sched_scan_results(struct wiphy *wiphy)
329 {
330 trace_cfg80211_sched_scan_results(wiphy);
331 /* ignore if we're not scanning */
332
333 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
334 queue_work(cfg80211_wq,
335 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
336 }
337 EXPORT_SYMBOL(cfg80211_sched_scan_results);
338
339 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
340 {
341 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
342
343 ASSERT_RTNL();
344
345 trace_cfg80211_sched_scan_stopped(wiphy);
346
347 __cfg80211_stop_sched_scan(rdev, true);
348 }
349 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
350
351 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
352 {
353 rtnl_lock();
354 cfg80211_sched_scan_stopped_rtnl(wiphy);
355 rtnl_unlock();
356 }
357 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
358
359 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
360 bool driver_initiated)
361 {
362 struct cfg80211_sched_scan_request *sched_scan_req;
363 struct net_device *dev;
364
365 ASSERT_RTNL();
366
367 if (!rdev->sched_scan_req)
368 return -ENOENT;
369
370 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
371 dev = sched_scan_req->dev;
372
373 if (!driver_initiated) {
374 int err = rdev_sched_scan_stop(rdev, dev);
375 if (err)
376 return err;
377 }
378
379 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
380
381 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
382 kfree_rcu(sched_scan_req, rcu_head);
383
384 return 0;
385 }
386
387 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
388 unsigned long age_secs)
389 {
390 struct cfg80211_internal_bss *bss;
391 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
392
393 spin_lock_bh(&rdev->bss_lock);
394 list_for_each_entry(bss, &rdev->bss_list, list)
395 bss->ts -= age_jiffies;
396 spin_unlock_bh(&rdev->bss_lock);
397 }
398
399 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
400 {
401 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
402 }
403
404 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
405 {
406 while (len > 2 && ies[0] != eid) {
407 len -= ies[1] + 2;
408 ies += ies[1] + 2;
409 }
410 if (len < 2)
411 return NULL;
412 if (len < 2 + ies[1])
413 return NULL;
414 return ies;
415 }
416 EXPORT_SYMBOL(cfg80211_find_ie);
417
418 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
419 const u8 *ies, int len)
420 {
421 struct ieee80211_vendor_ie *ie;
422 const u8 *pos = ies, *end = ies + len;
423 int ie_oui;
424
425 while (pos < end) {
426 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
427 end - pos);
428 if (!pos)
429 return NULL;
430
431 ie = (struct ieee80211_vendor_ie *)pos;
432
433 /* make sure we can access ie->len */
434 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
435
436 if (ie->len < sizeof(*ie))
437 goto cont;
438
439 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
440 if (ie_oui == oui && ie->oui_type == oui_type)
441 return pos;
442 cont:
443 pos += 2 + ie->len;
444 }
445 return NULL;
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 ieee80211_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 == IEEE80211_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 } else {
905 struct cfg80211_internal_bss *new;
906 struct cfg80211_internal_bss *hidden;
907 struct cfg80211_bss_ies *ies;
908
909 /*
910 * create a copy -- the "res" variable that is passed in
911 * is allocated on the stack since it's not needed in the
912 * more common case of an update
913 */
914 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
915 GFP_ATOMIC);
916 if (!new) {
917 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
918 if (ies)
919 kfree_rcu(ies, rcu_head);
920 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
921 if (ies)
922 kfree_rcu(ies, rcu_head);
923 goto drop;
924 }
925 memcpy(new, tmp, sizeof(*new));
926 new->refcount = 1;
927 INIT_LIST_HEAD(&new->hidden_list);
928
929 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
930 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
931 if (!hidden)
932 hidden = rb_find_bss(rdev, tmp,
933 BSS_CMP_HIDE_NUL);
934 if (hidden) {
935 new->pub.hidden_beacon_bss = &hidden->pub;
936 list_add(&new->hidden_list,
937 &hidden->hidden_list);
938 hidden->refcount++;
939 rcu_assign_pointer(new->pub.beacon_ies,
940 hidden->pub.beacon_ies);
941 }
942 } else {
943 /*
944 * Ok so we found a beacon, and don't have an entry. If
945 * it's a beacon with hidden SSID, we might be in for an
946 * expensive search for any probe responses that should
947 * be grouped with this beacon for updates ...
948 */
949 if (!cfg80211_combine_bsses(rdev, new)) {
950 kfree(new);
951 goto drop;
952 }
953 }
954
955 if (rdev->bss_entries >= bss_entries_limit &&
956 !cfg80211_bss_expire_oldest(rdev)) {
957 kfree(new);
958 goto drop;
959 }
960
961 list_add_tail(&new->list, &rdev->bss_list);
962 rdev->bss_entries++;
963 rb_insert_bss(rdev, new);
964 found = new;
965 }
966
967 rdev->bss_generation++;
968 bss_ref_get(rdev, found);
969 spin_unlock_bh(&rdev->bss_lock);
970
971 return found;
972 drop:
973 spin_unlock_bh(&rdev->bss_lock);
974 return NULL;
975 }
976
977 static struct ieee80211_channel *
978 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
979 struct ieee80211_channel *channel)
980 {
981 const u8 *tmp;
982 u32 freq;
983 int channel_number = -1;
984
985 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
986 if (tmp && tmp[1] == 1) {
987 channel_number = tmp[2];
988 } else {
989 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
990 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
991 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
992
993 channel_number = htop->primary_chan;
994 }
995 }
996
997 if (channel_number < 0)
998 return channel;
999
1000 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
1001 channel = ieee80211_get_channel(wiphy, freq);
1002 if (!channel)
1003 return NULL;
1004 if (channel->flags & IEEE80211_CHAN_DISABLED)
1005 return NULL;
1006 return channel;
1007 }
1008
1009 /* Returned bss is reference counted and must be cleaned up appropriately. */
1010 struct cfg80211_bss *
1011 cfg80211_inform_bss_data(struct wiphy *wiphy,
1012 struct cfg80211_inform_bss *data,
1013 enum cfg80211_bss_frame_type ftype,
1014 const u8 *bssid, u64 tsf, u16 capability,
1015 u16 beacon_interval, const u8 *ie, size_t ielen,
1016 gfp_t gfp)
1017 {
1018 struct cfg80211_bss_ies *ies;
1019 struct ieee80211_channel *channel;
1020 struct cfg80211_internal_bss tmp = {}, *res;
1021 int bss_type;
1022 bool signal_valid;
1023
1024 if (WARN_ON(!wiphy))
1025 return NULL;
1026
1027 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1028 (data->signal < 0 || data->signal > 100)))
1029 return NULL;
1030
1031 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan);
1032 if (!channel)
1033 return NULL;
1034
1035 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1036 tmp.pub.channel = channel;
1037 tmp.pub.scan_width = data->scan_width;
1038 tmp.pub.signal = data->signal;
1039 tmp.pub.beacon_interval = beacon_interval;
1040 tmp.pub.capability = capability;
1041 tmp.ts_boottime = data->boottime_ns;
1042
1043 /*
1044 * If we do not know here whether the IEs are from a Beacon or Probe
1045 * Response frame, we need to pick one of the options and only use it
1046 * with the driver that does not provide the full Beacon/Probe Response
1047 * frame. Use Beacon frame pointer to avoid indicating that this should
1048 * override the IEs pointer should we have received an earlier
1049 * indication of Probe Response data.
1050 */
1051 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1052 if (!ies)
1053 return NULL;
1054 ies->len = ielen;
1055 ies->tsf = tsf;
1056 ies->from_beacon = false;
1057 memcpy(ies->data, ie, ielen);
1058
1059 switch (ftype) {
1060 case CFG80211_BSS_FTYPE_BEACON:
1061 ies->from_beacon = true;
1062 /* fall through to assign */
1063 case CFG80211_BSS_FTYPE_UNKNOWN:
1064 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1065 break;
1066 case CFG80211_BSS_FTYPE_PRESP:
1067 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1068 break;
1069 }
1070 rcu_assign_pointer(tmp.pub.ies, ies);
1071
1072 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1073 wiphy->max_adj_channel_rssi_comp;
1074 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1075 if (!res)
1076 return NULL;
1077
1078 if (channel->band == IEEE80211_BAND_60GHZ) {
1079 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1080 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1081 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1082 regulatory_hint_found_beacon(wiphy, channel, gfp);
1083 } else {
1084 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1085 regulatory_hint_found_beacon(wiphy, channel, gfp);
1086 }
1087
1088 trace_cfg80211_return_bss(&res->pub);
1089 /* cfg80211_bss_update gives us a referenced result */
1090 return &res->pub;
1091 }
1092 EXPORT_SYMBOL(cfg80211_inform_bss_data);
1093
1094 /* cfg80211_inform_bss_width_frame helper */
1095 struct cfg80211_bss *
1096 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1097 struct cfg80211_inform_bss *data,
1098 struct ieee80211_mgmt *mgmt, size_t len,
1099 gfp_t gfp)
1100
1101 {
1102 struct cfg80211_internal_bss tmp = {}, *res;
1103 struct cfg80211_bss_ies *ies;
1104 struct ieee80211_channel *channel;
1105 bool signal_valid;
1106 size_t ielen = len - offsetof(struct ieee80211_mgmt,
1107 u.probe_resp.variable);
1108 int bss_type;
1109
1110 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1111 offsetof(struct ieee80211_mgmt, u.beacon.variable));
1112
1113 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1114
1115 if (WARN_ON(!mgmt))
1116 return NULL;
1117
1118 if (WARN_ON(!wiphy))
1119 return NULL;
1120
1121 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1122 (data->signal < 0 || data->signal > 100)))
1123 return NULL;
1124
1125 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1126 return NULL;
1127
1128 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1129 ielen, data->chan);
1130 if (!channel)
1131 return NULL;
1132
1133 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1134 if (!ies)
1135 return NULL;
1136 ies->len = ielen;
1137 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1138 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1139 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1140
1141 if (ieee80211_is_probe_resp(mgmt->frame_control))
1142 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1143 else
1144 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1145 rcu_assign_pointer(tmp.pub.ies, ies);
1146
1147 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1148 tmp.pub.channel = channel;
1149 tmp.pub.scan_width = data->scan_width;
1150 tmp.pub.signal = data->signal;
1151 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1152 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1153 tmp.ts_boottime = data->boottime_ns;
1154
1155 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1156 wiphy->max_adj_channel_rssi_comp;
1157 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1158 if (!res)
1159 return NULL;
1160
1161 if (channel->band == IEEE80211_BAND_60GHZ) {
1162 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1163 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1164 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1165 regulatory_hint_found_beacon(wiphy, channel, gfp);
1166 } else {
1167 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1168 regulatory_hint_found_beacon(wiphy, channel, gfp);
1169 }
1170
1171 trace_cfg80211_return_bss(&res->pub);
1172 /* cfg80211_bss_update gives us a referenced result */
1173 return &res->pub;
1174 }
1175 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1176
1177 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1178 {
1179 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1180 struct cfg80211_internal_bss *bss;
1181
1182 if (!pub)
1183 return;
1184
1185 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1186
1187 spin_lock_bh(&rdev->bss_lock);
1188 bss_ref_get(rdev, bss);
1189 spin_unlock_bh(&rdev->bss_lock);
1190 }
1191 EXPORT_SYMBOL(cfg80211_ref_bss);
1192
1193 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1194 {
1195 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1196 struct cfg80211_internal_bss *bss;
1197
1198 if (!pub)
1199 return;
1200
1201 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1202
1203 spin_lock_bh(&rdev->bss_lock);
1204 bss_ref_put(rdev, bss);
1205 spin_unlock_bh(&rdev->bss_lock);
1206 }
1207 EXPORT_SYMBOL(cfg80211_put_bss);
1208
1209 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1210 {
1211 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1212 struct cfg80211_internal_bss *bss;
1213
1214 if (WARN_ON(!pub))
1215 return;
1216
1217 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1218
1219 spin_lock_bh(&rdev->bss_lock);
1220 if (!list_empty(&bss->list)) {
1221 if (__cfg80211_unlink_bss(rdev, bss))
1222 rdev->bss_generation++;
1223 }
1224 spin_unlock_bh(&rdev->bss_lock);
1225 }
1226 EXPORT_SYMBOL(cfg80211_unlink_bss);
1227
1228 #ifdef CONFIG_CFG80211_WEXT
1229 static struct cfg80211_registered_device *
1230 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1231 {
1232 struct cfg80211_registered_device *rdev;
1233 struct net_device *dev;
1234
1235 ASSERT_RTNL();
1236
1237 dev = dev_get_by_index(net, ifindex);
1238 if (!dev)
1239 return ERR_PTR(-ENODEV);
1240 if (dev->ieee80211_ptr)
1241 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1242 else
1243 rdev = ERR_PTR(-ENODEV);
1244 dev_put(dev);
1245 return rdev;
1246 }
1247
1248 int cfg80211_wext_siwscan(struct net_device *dev,
1249 struct iw_request_info *info,
1250 union iwreq_data *wrqu, char *extra)
1251 {
1252 struct cfg80211_registered_device *rdev;
1253 struct wiphy *wiphy;
1254 struct iw_scan_req *wreq = NULL;
1255 struct cfg80211_scan_request *creq = NULL;
1256 int i, err, n_channels = 0;
1257 enum ieee80211_band band;
1258
1259 if (!netif_running(dev))
1260 return -ENETDOWN;
1261
1262 if (wrqu->data.length == sizeof(struct iw_scan_req))
1263 wreq = (struct iw_scan_req *)extra;
1264
1265 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1266
1267 if (IS_ERR(rdev))
1268 return PTR_ERR(rdev);
1269
1270 if (rdev->scan_req || rdev->scan_msg) {
1271 err = -EBUSY;
1272 goto out;
1273 }
1274
1275 wiphy = &rdev->wiphy;
1276
1277 /* Determine number of channels, needed to allocate creq */
1278 if (wreq && wreq->num_channels)
1279 n_channels = wreq->num_channels;
1280 else
1281 n_channels = ieee80211_get_num_supported_channels(wiphy);
1282
1283 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1284 n_channels * sizeof(void *),
1285 GFP_ATOMIC);
1286 if (!creq) {
1287 err = -ENOMEM;
1288 goto out;
1289 }
1290
1291 creq->wiphy = wiphy;
1292 creq->wdev = dev->ieee80211_ptr;
1293 /* SSIDs come after channels */
1294 creq->ssids = (void *)&creq->channels[n_channels];
1295 creq->n_channels = n_channels;
1296 creq->n_ssids = 1;
1297 creq->scan_start = jiffies;
1298
1299 /* translate "Scan on frequencies" request */
1300 i = 0;
1301 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1302 int j;
1303
1304 if (!wiphy->bands[band])
1305 continue;
1306
1307 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1308 /* ignore disabled channels */
1309 if (wiphy->bands[band]->channels[j].flags &
1310 IEEE80211_CHAN_DISABLED)
1311 continue;
1312
1313 /* If we have a wireless request structure and the
1314 * wireless request specifies frequencies, then search
1315 * for the matching hardware channel.
1316 */
1317 if (wreq && wreq->num_channels) {
1318 int k;
1319 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1320 for (k = 0; k < wreq->num_channels; k++) {
1321 struct iw_freq *freq =
1322 &wreq->channel_list[k];
1323 int wext_freq =
1324 cfg80211_wext_freq(freq);
1325
1326 if (wext_freq == wiphy_freq)
1327 goto wext_freq_found;
1328 }
1329 goto wext_freq_not_found;
1330 }
1331
1332 wext_freq_found:
1333 creq->channels[i] = &wiphy->bands[band]->channels[j];
1334 i++;
1335 wext_freq_not_found: ;
1336 }
1337 }
1338 /* No channels found? */
1339 if (!i) {
1340 err = -EINVAL;
1341 goto out;
1342 }
1343
1344 /* Set real number of channels specified in creq->channels[] */
1345 creq->n_channels = i;
1346
1347 /* translate "Scan for SSID" request */
1348 if (wreq) {
1349 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1350 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1351 err = -EINVAL;
1352 goto out;
1353 }
1354 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1355 creq->ssids[0].ssid_len = wreq->essid_len;
1356 }
1357 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1358 creq->n_ssids = 0;
1359 }
1360
1361 for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1362 if (wiphy->bands[i])
1363 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1364
1365 rdev->scan_req = creq;
1366 err = rdev_scan(rdev, creq);
1367 if (err) {
1368 rdev->scan_req = NULL;
1369 /* creq will be freed below */
1370 } else {
1371 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1372 /* creq now owned by driver */
1373 creq = NULL;
1374 dev_hold(dev);
1375 }
1376 out:
1377 kfree(creq);
1378 return err;
1379 }
1380 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1381
1382 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1383 const struct cfg80211_bss_ies *ies,
1384 char *current_ev, char *end_buf)
1385 {
1386 const u8 *pos, *end, *next;
1387 struct iw_event iwe;
1388
1389 if (!ies)
1390 return current_ev;
1391
1392 /*
1393 * If needed, fragment the IEs buffer (at IE boundaries) into short
1394 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1395 */
1396 pos = ies->data;
1397 end = pos + ies->len;
1398
1399 while (end - pos > IW_GENERIC_IE_MAX) {
1400 next = pos + 2 + pos[1];
1401 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1402 next = next + 2 + next[1];
1403
1404 memset(&iwe, 0, sizeof(iwe));
1405 iwe.cmd = IWEVGENIE;
1406 iwe.u.data.length = next - pos;
1407 current_ev = iwe_stream_add_point_check(info, current_ev,
1408 end_buf, &iwe,
1409 (void *)pos);
1410 if (IS_ERR(current_ev))
1411 return current_ev;
1412 pos = next;
1413 }
1414
1415 if (end > pos) {
1416 memset(&iwe, 0, sizeof(iwe));
1417 iwe.cmd = IWEVGENIE;
1418 iwe.u.data.length = end - pos;
1419 current_ev = iwe_stream_add_point_check(info, current_ev,
1420 end_buf, &iwe,
1421 (void *)pos);
1422 if (IS_ERR(current_ev))
1423 return current_ev;
1424 }
1425
1426 return current_ev;
1427 }
1428
1429 static char *
1430 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1431 struct cfg80211_internal_bss *bss, char *current_ev,
1432 char *end_buf)
1433 {
1434 const struct cfg80211_bss_ies *ies;
1435 struct iw_event iwe;
1436 const u8 *ie;
1437 u8 buf[50];
1438 u8 *cfg, *p, *tmp;
1439 int rem, i, sig;
1440 bool ismesh = false;
1441
1442 memset(&iwe, 0, sizeof(iwe));
1443 iwe.cmd = SIOCGIWAP;
1444 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1445 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1446 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1447 IW_EV_ADDR_LEN);
1448 if (IS_ERR(current_ev))
1449 return current_ev;
1450
1451 memset(&iwe, 0, sizeof(iwe));
1452 iwe.cmd = SIOCGIWFREQ;
1453 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1454 iwe.u.freq.e = 0;
1455 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1456 IW_EV_FREQ_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 = bss->pub.channel->center_freq;
1463 iwe.u.freq.e = 6;
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 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1470 memset(&iwe, 0, sizeof(iwe));
1471 iwe.cmd = IWEVQUAL;
1472 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1473 IW_QUAL_NOISE_INVALID |
1474 IW_QUAL_QUAL_UPDATED;
1475 switch (wiphy->signal_type) {
1476 case CFG80211_SIGNAL_TYPE_MBM:
1477 sig = bss->pub.signal / 100;
1478 iwe.u.qual.level = sig;
1479 iwe.u.qual.updated |= IW_QUAL_DBM;
1480 if (sig < -110) /* rather bad */
1481 sig = -110;
1482 else if (sig > -40) /* perfect */
1483 sig = -40;
1484 /* will give a range of 0 .. 70 */
1485 iwe.u.qual.qual = sig + 110;
1486 break;
1487 case CFG80211_SIGNAL_TYPE_UNSPEC:
1488 iwe.u.qual.level = bss->pub.signal;
1489 /* will give range 0 .. 100 */
1490 iwe.u.qual.qual = bss->pub.signal;
1491 break;
1492 default:
1493 /* not reached */
1494 break;
1495 }
1496 current_ev = iwe_stream_add_event_check(info, current_ev,
1497 end_buf, &iwe,
1498 IW_EV_QUAL_LEN);
1499 if (IS_ERR(current_ev))
1500 return current_ev;
1501 }
1502
1503 memset(&iwe, 0, sizeof(iwe));
1504 iwe.cmd = SIOCGIWENCODE;
1505 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1506 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1507 else
1508 iwe.u.data.flags = IW_ENCODE_DISABLED;
1509 iwe.u.data.length = 0;
1510 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1511 &iwe, "");
1512 if (IS_ERR(current_ev))
1513 return current_ev;
1514
1515 rcu_read_lock();
1516 ies = rcu_dereference(bss->pub.ies);
1517 rem = ies->len;
1518 ie = ies->data;
1519
1520 while (rem >= 2) {
1521 /* invalid data */
1522 if (ie[1] > rem - 2)
1523 break;
1524
1525 switch (ie[0]) {
1526 case WLAN_EID_SSID:
1527 memset(&iwe, 0, sizeof(iwe));
1528 iwe.cmd = SIOCGIWESSID;
1529 iwe.u.data.length = ie[1];
1530 iwe.u.data.flags = 1;
1531 current_ev = iwe_stream_add_point_check(info,
1532 current_ev,
1533 end_buf, &iwe,
1534 (u8 *)ie + 2);
1535 if (IS_ERR(current_ev))
1536 goto unlock;
1537 break;
1538 case WLAN_EID_MESH_ID:
1539 memset(&iwe, 0, sizeof(iwe));
1540 iwe.cmd = SIOCGIWESSID;
1541 iwe.u.data.length = ie[1];
1542 iwe.u.data.flags = 1;
1543 current_ev = iwe_stream_add_point_check(info,
1544 current_ev,
1545 end_buf, &iwe,
1546 (u8 *)ie + 2);
1547 if (IS_ERR(current_ev))
1548 goto unlock;
1549 break;
1550 case WLAN_EID_MESH_CONFIG:
1551 ismesh = true;
1552 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1553 break;
1554 cfg = (u8 *)ie + 2;
1555 memset(&iwe, 0, sizeof(iwe));
1556 iwe.cmd = IWEVCUSTOM;
1557 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1558 "0x%02X", cfg[0]);
1559 iwe.u.data.length = strlen(buf);
1560 current_ev = iwe_stream_add_point_check(info,
1561 current_ev,
1562 end_buf,
1563 &iwe, buf);
1564 if (IS_ERR(current_ev))
1565 goto unlock;
1566 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1567 cfg[1]);
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, "Congestion Control Mode ID: 0x%02X",
1576 cfg[2]);
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, "Synchronization ID: 0x%02X", cfg[3]);
1585 iwe.u.data.length = strlen(buf);
1586 current_ev = iwe_stream_add_point_check(info,
1587 current_ev,
1588 end_buf,
1589 &iwe, buf);
1590 if (IS_ERR(current_ev))
1591 goto unlock;
1592 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1593 iwe.u.data.length = strlen(buf);
1594 current_ev = iwe_stream_add_point_check(info,
1595 current_ev,
1596 end_buf,
1597 &iwe, buf);
1598 if (IS_ERR(current_ev))
1599 goto unlock;
1600 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1601 iwe.u.data.length = strlen(buf);
1602 current_ev = iwe_stream_add_point_check(info,
1603 current_ev,
1604 end_buf,
1605 &iwe, buf);
1606 if (IS_ERR(current_ev))
1607 goto unlock;
1608 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1609 iwe.u.data.length = strlen(buf);
1610 current_ev = iwe_stream_add_point_check(info,
1611 current_ev,
1612 end_buf,
1613 &iwe, buf);
1614 if (IS_ERR(current_ev))
1615 goto unlock;
1616 break;
1617 case WLAN_EID_SUPP_RATES:
1618 case WLAN_EID_EXT_SUPP_RATES:
1619 /* display all supported rates in readable format */
1620 p = current_ev + iwe_stream_lcp_len(info);
1621
1622 memset(&iwe, 0, sizeof(iwe));
1623 iwe.cmd = SIOCGIWRATE;
1624 /* Those two flags are ignored... */
1625 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1626
1627 for (i = 0; i < ie[1]; i++) {
1628 iwe.u.bitrate.value =
1629 ((ie[i + 2] & 0x7f) * 500000);
1630 tmp = p;
1631 p = iwe_stream_add_value(info, current_ev, p,
1632 end_buf, &iwe,
1633 IW_EV_PARAM_LEN);
1634 if (p == tmp) {
1635 current_ev = ERR_PTR(-E2BIG);
1636 goto unlock;
1637 }
1638 }
1639 current_ev = p;
1640 break;
1641 }
1642 rem -= ie[1] + 2;
1643 ie += ie[1] + 2;
1644 }
1645
1646 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1647 ismesh) {
1648 memset(&iwe, 0, sizeof(iwe));
1649 iwe.cmd = SIOCGIWMODE;
1650 if (ismesh)
1651 iwe.u.mode = IW_MODE_MESH;
1652 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1653 iwe.u.mode = IW_MODE_MASTER;
1654 else
1655 iwe.u.mode = IW_MODE_ADHOC;
1656 current_ev = iwe_stream_add_event_check(info, current_ev,
1657 end_buf, &iwe,
1658 IW_EV_UINT_LEN);
1659 if (IS_ERR(current_ev))
1660 goto unlock;
1661 }
1662
1663 memset(&iwe, 0, sizeof(iwe));
1664 iwe.cmd = IWEVCUSTOM;
1665 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1666 iwe.u.data.length = strlen(buf);
1667 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1668 &iwe, buf);
1669 if (IS_ERR(current_ev))
1670 goto unlock;
1671 memset(&iwe, 0, sizeof(iwe));
1672 iwe.cmd = IWEVCUSTOM;
1673 sprintf(buf, " Last beacon: %ums ago",
1674 elapsed_jiffies_msecs(bss->ts));
1675 iwe.u.data.length = strlen(buf);
1676 current_ev = iwe_stream_add_point_check(info, current_ev,
1677 end_buf, &iwe, buf);
1678 if (IS_ERR(current_ev))
1679 goto unlock;
1680
1681 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1682
1683 unlock:
1684 rcu_read_unlock();
1685 return current_ev;
1686 }
1687
1688
1689 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1690 struct iw_request_info *info,
1691 char *buf, size_t len)
1692 {
1693 char *current_ev = buf;
1694 char *end_buf = buf + len;
1695 struct cfg80211_internal_bss *bss;
1696 int err = 0;
1697
1698 spin_lock_bh(&rdev->bss_lock);
1699 cfg80211_bss_expire(rdev);
1700
1701 list_for_each_entry(bss, &rdev->bss_list, list) {
1702 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1703 err = -E2BIG;
1704 break;
1705 }
1706 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1707 current_ev, end_buf);
1708 if (IS_ERR(current_ev)) {
1709 err = PTR_ERR(current_ev);
1710 break;
1711 }
1712 }
1713 spin_unlock_bh(&rdev->bss_lock);
1714
1715 if (err)
1716 return err;
1717 return current_ev - buf;
1718 }
1719
1720
1721 int cfg80211_wext_giwscan(struct net_device *dev,
1722 struct iw_request_info *info,
1723 struct iw_point *data, char *extra)
1724 {
1725 struct cfg80211_registered_device *rdev;
1726 int res;
1727
1728 if (!netif_running(dev))
1729 return -ENETDOWN;
1730
1731 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1732
1733 if (IS_ERR(rdev))
1734 return PTR_ERR(rdev);
1735
1736 if (rdev->scan_req || rdev->scan_msg)
1737 return -EAGAIN;
1738
1739 res = ieee80211_scan_results(rdev, info, extra, data->length);
1740 data->length = 0;
1741 if (res >= 0) {
1742 data->length = res;
1743 res = 0;
1744 }
1745
1746 return res;
1747 }
1748 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1749 #endif