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Merge tag 'nios2-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2
[mirror_ubuntu-bionic-kernel.git] / net / wireless / scan.c
1 /*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 * Copyright 2013-2014 Intel Mobile Communications GmbH
6 */
7 #include <linux/kernel.h>
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/netdevice.h>
11 #include <linux/wireless.h>
12 #include <linux/nl80211.h>
13 #include <linux/etherdevice.h>
14 #include <net/arp.h>
15 #include <net/cfg80211.h>
16 #include <net/cfg80211-wext.h>
17 #include <net/iw_handler.h>
18 #include "core.h"
19 #include "nl80211.h"
20 #include "wext-compat.h"
21 #include "rdev-ops.h"
22
23 /**
24 * DOC: BSS tree/list structure
25 *
26 * At the top level, the BSS list is kept in both a list in each
27 * registered device (@bss_list) as well as an RB-tree for faster
28 * lookup. In the RB-tree, entries can be looked up using their
29 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
30 * for other BSSes.
31 *
32 * Due to the possibility of hidden SSIDs, there's a second level
33 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
34 * The hidden_list connects all BSSes belonging to a single AP
35 * that has a hidden SSID, and connects beacon and probe response
36 * entries. For a probe response entry for a hidden SSID, the
37 * hidden_beacon_bss pointer points to the BSS struct holding the
38 * beacon's information.
39 *
40 * Reference counting is done for all these references except for
41 * the hidden_list, so that a beacon BSS struct that is otherwise
42 * not referenced has one reference for being on the bss_list and
43 * one for each probe response entry that points to it using the
44 * hidden_beacon_bss pointer. When a BSS struct that has such a
45 * pointer is get/put, the refcount update is also propagated to
46 * the referenced struct, this ensure that it cannot get removed
47 * while somebody is using the probe response version.
48 *
49 * Note that the hidden_beacon_bss pointer never changes, due to
50 * the reference counting. Therefore, no locking is needed for
51 * it.
52 *
53 * Also note that the hidden_beacon_bss pointer is only relevant
54 * if the driver uses something other than the IEs, e.g. private
55 * data stored stored in the BSS struct, since the beacon IEs are
56 * also linked into the probe response struct.
57 */
58
59 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
60
61 static void bss_free(struct cfg80211_internal_bss *bss)
62 {
63 struct cfg80211_bss_ies *ies;
64
65 if (WARN_ON(atomic_read(&bss->hold)))
66 return;
67
68 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
69 if (ies && !bss->pub.hidden_beacon_bss)
70 kfree_rcu(ies, rcu_head);
71 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
72 if (ies)
73 kfree_rcu(ies, rcu_head);
74
75 /*
76 * This happens when the module is removed, it doesn't
77 * really matter any more save for completeness
78 */
79 if (!list_empty(&bss->hidden_list))
80 list_del(&bss->hidden_list);
81
82 kfree(bss);
83 }
84
85 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
86 struct cfg80211_internal_bss *bss)
87 {
88 lockdep_assert_held(&rdev->bss_lock);
89
90 bss->refcount++;
91 if (bss->pub.hidden_beacon_bss) {
92 bss = container_of(bss->pub.hidden_beacon_bss,
93 struct cfg80211_internal_bss,
94 pub);
95 bss->refcount++;
96 }
97 }
98
99 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
100 struct cfg80211_internal_bss *bss)
101 {
102 lockdep_assert_held(&rdev->bss_lock);
103
104 if (bss->pub.hidden_beacon_bss) {
105 struct cfg80211_internal_bss *hbss;
106 hbss = container_of(bss->pub.hidden_beacon_bss,
107 struct cfg80211_internal_bss,
108 pub);
109 hbss->refcount--;
110 if (hbss->refcount == 0)
111 bss_free(hbss);
112 }
113 bss->refcount--;
114 if (bss->refcount == 0)
115 bss_free(bss);
116 }
117
118 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
119 struct cfg80211_internal_bss *bss)
120 {
121 lockdep_assert_held(&rdev->bss_lock);
122
123 if (!list_empty(&bss->hidden_list)) {
124 /*
125 * don't remove the beacon entry if it has
126 * probe responses associated with it
127 */
128 if (!bss->pub.hidden_beacon_bss)
129 return false;
130 /*
131 * if it's a probe response entry break its
132 * link to the other entries in the group
133 */
134 list_del_init(&bss->hidden_list);
135 }
136
137 list_del_init(&bss->list);
138 rb_erase(&bss->rbn, &rdev->bss_tree);
139 bss_ref_put(rdev, bss);
140 return true;
141 }
142
143 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
144 unsigned long expire_time)
145 {
146 struct cfg80211_internal_bss *bss, *tmp;
147 bool expired = false;
148
149 lockdep_assert_held(&rdev->bss_lock);
150
151 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
152 if (atomic_read(&bss->hold))
153 continue;
154 if (!time_after(expire_time, bss->ts))
155 continue;
156
157 if (__cfg80211_unlink_bss(rdev, bss))
158 expired = true;
159 }
160
161 if (expired)
162 rdev->bss_generation++;
163 }
164
165 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
166 bool send_message)
167 {
168 struct cfg80211_scan_request *request;
169 struct wireless_dev *wdev;
170 struct sk_buff *msg;
171 #ifdef CONFIG_CFG80211_WEXT
172 union iwreq_data wrqu;
173 #endif
174
175 ASSERT_RTNL();
176
177 if (rdev->scan_msg) {
178 nl80211_send_scan_result(rdev, rdev->scan_msg);
179 rdev->scan_msg = NULL;
180 return;
181 }
182
183 request = rdev->scan_req;
184 if (!request)
185 return;
186
187 wdev = request->wdev;
188
189 /*
190 * This must be before sending the other events!
191 * Otherwise, wpa_supplicant gets completely confused with
192 * wext events.
193 */
194 if (wdev->netdev)
195 cfg80211_sme_scan_done(wdev->netdev);
196
197 if (!request->aborted &&
198 request->flags & NL80211_SCAN_FLAG_FLUSH) {
199 /* flush entries from previous scans */
200 spin_lock_bh(&rdev->bss_lock);
201 __cfg80211_bss_expire(rdev, request->scan_start);
202 spin_unlock_bh(&rdev->bss_lock);
203 }
204
205 msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
206
207 #ifdef CONFIG_CFG80211_WEXT
208 if (wdev->netdev && !request->aborted) {
209 memset(&wrqu, 0, sizeof(wrqu));
210
211 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
212 }
213 #endif
214
215 if (wdev->netdev)
216 dev_put(wdev->netdev);
217
218 rdev->scan_req = NULL;
219 kfree(request);
220
221 if (!send_message)
222 rdev->scan_msg = msg;
223 else
224 nl80211_send_scan_result(rdev, msg);
225 }
226
227 void __cfg80211_scan_done(struct work_struct *wk)
228 {
229 struct cfg80211_registered_device *rdev;
230
231 rdev = container_of(wk, struct cfg80211_registered_device,
232 scan_done_wk);
233
234 rtnl_lock();
235 ___cfg80211_scan_done(rdev, true);
236 rtnl_unlock();
237 }
238
239 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
240 {
241 trace_cfg80211_scan_done(request, aborted);
242 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
243
244 request->aborted = aborted;
245 request->notified = true;
246 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
247 }
248 EXPORT_SYMBOL(cfg80211_scan_done);
249
250 void __cfg80211_sched_scan_results(struct work_struct *wk)
251 {
252 struct cfg80211_registered_device *rdev;
253 struct cfg80211_sched_scan_request *request;
254
255 rdev = container_of(wk, struct cfg80211_registered_device,
256 sched_scan_results_wk);
257
258 rtnl_lock();
259
260 request = rtnl_dereference(rdev->sched_scan_req);
261
262 /* we don't have sched_scan_req anymore if the scan is stopping */
263 if (request) {
264 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
265 /* flush entries from previous scans */
266 spin_lock_bh(&rdev->bss_lock);
267 __cfg80211_bss_expire(rdev, request->scan_start);
268 spin_unlock_bh(&rdev->bss_lock);
269 request->scan_start = jiffies;
270 }
271 nl80211_send_sched_scan_results(rdev, request->dev);
272 }
273
274 rtnl_unlock();
275 }
276
277 void cfg80211_sched_scan_results(struct wiphy *wiphy)
278 {
279 trace_cfg80211_sched_scan_results(wiphy);
280 /* ignore if we're not scanning */
281
282 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
283 queue_work(cfg80211_wq,
284 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
285 }
286 EXPORT_SYMBOL(cfg80211_sched_scan_results);
287
288 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
289 {
290 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
291
292 ASSERT_RTNL();
293
294 trace_cfg80211_sched_scan_stopped(wiphy);
295
296 __cfg80211_stop_sched_scan(rdev, true);
297 }
298 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
299
300 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
301 {
302 rtnl_lock();
303 cfg80211_sched_scan_stopped_rtnl(wiphy);
304 rtnl_unlock();
305 }
306 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
307
308 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
309 bool driver_initiated)
310 {
311 struct cfg80211_sched_scan_request *sched_scan_req;
312 struct net_device *dev;
313
314 ASSERT_RTNL();
315
316 if (!rdev->sched_scan_req)
317 return -ENOENT;
318
319 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
320 dev = sched_scan_req->dev;
321
322 if (!driver_initiated) {
323 int err = rdev_sched_scan_stop(rdev, dev);
324 if (err)
325 return err;
326 }
327
328 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
329
330 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
331 kfree_rcu(sched_scan_req, rcu_head);
332
333 return 0;
334 }
335
336 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
337 unsigned long age_secs)
338 {
339 struct cfg80211_internal_bss *bss;
340 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
341
342 spin_lock_bh(&rdev->bss_lock);
343 list_for_each_entry(bss, &rdev->bss_list, list)
344 bss->ts -= age_jiffies;
345 spin_unlock_bh(&rdev->bss_lock);
346 }
347
348 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
349 {
350 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
351 }
352
353 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
354 {
355 while (len > 2 && ies[0] != eid) {
356 len -= ies[1] + 2;
357 ies += ies[1] + 2;
358 }
359 if (len < 2)
360 return NULL;
361 if (len < 2 + ies[1])
362 return NULL;
363 return ies;
364 }
365 EXPORT_SYMBOL(cfg80211_find_ie);
366
367 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
368 const u8 *ies, int len)
369 {
370 struct ieee80211_vendor_ie *ie;
371 const u8 *pos = ies, *end = ies + len;
372 int ie_oui;
373
374 if (WARN_ON(oui_type > 0xff))
375 return NULL;
376
377 while (pos < end) {
378 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
379 end - pos);
380 if (!pos)
381 return NULL;
382
383 ie = (struct ieee80211_vendor_ie *)pos;
384
385 /* make sure we can access ie->len */
386 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
387
388 if (ie->len < sizeof(*ie))
389 goto cont;
390
391 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
392 if (ie_oui == oui &&
393 (oui_type < 0 || ie->oui_type == oui_type))
394 return pos;
395 cont:
396 pos += 2 + ie->len;
397 }
398 return NULL;
399 }
400 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
401
402 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
403 const u8 *ssid, size_t ssid_len)
404 {
405 const struct cfg80211_bss_ies *ies;
406 const u8 *ssidie;
407
408 if (bssid && !ether_addr_equal(a->bssid, bssid))
409 return false;
410
411 if (!ssid)
412 return true;
413
414 ies = rcu_access_pointer(a->ies);
415 if (!ies)
416 return false;
417 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
418 if (!ssidie)
419 return false;
420 if (ssidie[1] != ssid_len)
421 return false;
422 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
423 }
424
425 /**
426 * enum bss_compare_mode - BSS compare mode
427 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
428 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
429 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
430 */
431 enum bss_compare_mode {
432 BSS_CMP_REGULAR,
433 BSS_CMP_HIDE_ZLEN,
434 BSS_CMP_HIDE_NUL,
435 };
436
437 static int cmp_bss(struct cfg80211_bss *a,
438 struct cfg80211_bss *b,
439 enum bss_compare_mode mode)
440 {
441 const struct cfg80211_bss_ies *a_ies, *b_ies;
442 const u8 *ie1 = NULL;
443 const u8 *ie2 = NULL;
444 int i, r;
445
446 if (a->channel != b->channel)
447 return b->channel->center_freq - a->channel->center_freq;
448
449 a_ies = rcu_access_pointer(a->ies);
450 if (!a_ies)
451 return -1;
452 b_ies = rcu_access_pointer(b->ies);
453 if (!b_ies)
454 return 1;
455
456 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
457 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
458 a_ies->data, a_ies->len);
459 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
460 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
461 b_ies->data, b_ies->len);
462 if (ie1 && ie2) {
463 int mesh_id_cmp;
464
465 if (ie1[1] == ie2[1])
466 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
467 else
468 mesh_id_cmp = ie2[1] - ie1[1];
469
470 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
471 a_ies->data, a_ies->len);
472 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
473 b_ies->data, b_ies->len);
474 if (ie1 && ie2) {
475 if (mesh_id_cmp)
476 return mesh_id_cmp;
477 if (ie1[1] != ie2[1])
478 return ie2[1] - ie1[1];
479 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
480 }
481 }
482
483 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
484 if (r)
485 return r;
486
487 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
488 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
489
490 if (!ie1 && !ie2)
491 return 0;
492
493 /*
494 * Note that with "hide_ssid", the function returns a match if
495 * the already-present BSS ("b") is a hidden SSID beacon for
496 * the new BSS ("a").
497 */
498
499 /* sort missing IE before (left of) present IE */
500 if (!ie1)
501 return -1;
502 if (!ie2)
503 return 1;
504
505 switch (mode) {
506 case BSS_CMP_HIDE_ZLEN:
507 /*
508 * In ZLEN mode we assume the BSS entry we're
509 * looking for has a zero-length SSID. So if
510 * the one we're looking at right now has that,
511 * return 0. Otherwise, return the difference
512 * in length, but since we're looking for the
513 * 0-length it's really equivalent to returning
514 * the length of the one we're looking at.
515 *
516 * No content comparison is needed as we assume
517 * the content length is zero.
518 */
519 return ie2[1];
520 case BSS_CMP_REGULAR:
521 default:
522 /* sort by length first, then by contents */
523 if (ie1[1] != ie2[1])
524 return ie2[1] - ie1[1];
525 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
526 case BSS_CMP_HIDE_NUL:
527 if (ie1[1] != ie2[1])
528 return ie2[1] - ie1[1];
529 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
530 for (i = 0; i < ie2[1]; i++)
531 if (ie2[i + 2])
532 return -1;
533 return 0;
534 }
535 }
536
537 static bool cfg80211_bss_type_match(u16 capability,
538 enum nl80211_band band,
539 enum ieee80211_bss_type bss_type)
540 {
541 bool ret = true;
542 u16 mask, val;
543
544 if (bss_type == IEEE80211_BSS_TYPE_ANY)
545 return ret;
546
547 if (band == NL80211_BAND_60GHZ) {
548 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
549 switch (bss_type) {
550 case IEEE80211_BSS_TYPE_ESS:
551 val = WLAN_CAPABILITY_DMG_TYPE_AP;
552 break;
553 case IEEE80211_BSS_TYPE_PBSS:
554 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
555 break;
556 case IEEE80211_BSS_TYPE_IBSS:
557 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
558 break;
559 default:
560 return false;
561 }
562 } else {
563 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
564 switch (bss_type) {
565 case IEEE80211_BSS_TYPE_ESS:
566 val = WLAN_CAPABILITY_ESS;
567 break;
568 case IEEE80211_BSS_TYPE_IBSS:
569 val = WLAN_CAPABILITY_IBSS;
570 break;
571 case IEEE80211_BSS_TYPE_MBSS:
572 val = 0;
573 break;
574 default:
575 return false;
576 }
577 }
578
579 ret = ((capability & mask) == val);
580 return ret;
581 }
582
583 /* Returned bss is reference counted and must be cleaned up appropriately. */
584 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
585 struct ieee80211_channel *channel,
586 const u8 *bssid,
587 const u8 *ssid, size_t ssid_len,
588 enum ieee80211_bss_type bss_type,
589 enum ieee80211_privacy privacy)
590 {
591 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
592 struct cfg80211_internal_bss *bss, *res = NULL;
593 unsigned long now = jiffies;
594 int bss_privacy;
595
596 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
597 privacy);
598
599 spin_lock_bh(&rdev->bss_lock);
600
601 list_for_each_entry(bss, &rdev->bss_list, list) {
602 if (!cfg80211_bss_type_match(bss->pub.capability,
603 bss->pub.channel->band, bss_type))
604 continue;
605
606 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
607 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
608 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
609 continue;
610 if (channel && bss->pub.channel != channel)
611 continue;
612 if (!is_valid_ether_addr(bss->pub.bssid))
613 continue;
614 /* Don't get expired BSS structs */
615 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
616 !atomic_read(&bss->hold))
617 continue;
618 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
619 res = bss;
620 bss_ref_get(rdev, res);
621 break;
622 }
623 }
624
625 spin_unlock_bh(&rdev->bss_lock);
626 if (!res)
627 return NULL;
628 trace_cfg80211_return_bss(&res->pub);
629 return &res->pub;
630 }
631 EXPORT_SYMBOL(cfg80211_get_bss);
632
633 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
634 struct cfg80211_internal_bss *bss)
635 {
636 struct rb_node **p = &rdev->bss_tree.rb_node;
637 struct rb_node *parent = NULL;
638 struct cfg80211_internal_bss *tbss;
639 int cmp;
640
641 while (*p) {
642 parent = *p;
643 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
644
645 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
646
647 if (WARN_ON(!cmp)) {
648 /* will sort of leak this BSS */
649 return;
650 }
651
652 if (cmp < 0)
653 p = &(*p)->rb_left;
654 else
655 p = &(*p)->rb_right;
656 }
657
658 rb_link_node(&bss->rbn, parent, p);
659 rb_insert_color(&bss->rbn, &rdev->bss_tree);
660 }
661
662 static struct cfg80211_internal_bss *
663 rb_find_bss(struct cfg80211_registered_device *rdev,
664 struct cfg80211_internal_bss *res,
665 enum bss_compare_mode mode)
666 {
667 struct rb_node *n = rdev->bss_tree.rb_node;
668 struct cfg80211_internal_bss *bss;
669 int r;
670
671 while (n) {
672 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
673 r = cmp_bss(&res->pub, &bss->pub, mode);
674
675 if (r == 0)
676 return bss;
677 else if (r < 0)
678 n = n->rb_left;
679 else
680 n = n->rb_right;
681 }
682
683 return NULL;
684 }
685
686 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
687 struct cfg80211_internal_bss *new)
688 {
689 const struct cfg80211_bss_ies *ies;
690 struct cfg80211_internal_bss *bss;
691 const u8 *ie;
692 int i, ssidlen;
693 u8 fold = 0;
694
695 ies = rcu_access_pointer(new->pub.beacon_ies);
696 if (WARN_ON(!ies))
697 return false;
698
699 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
700 if (!ie) {
701 /* nothing to do */
702 return true;
703 }
704
705 ssidlen = ie[1];
706 for (i = 0; i < ssidlen; i++)
707 fold |= ie[2 + i];
708
709 if (fold) {
710 /* not a hidden SSID */
711 return true;
712 }
713
714 /* This is the bad part ... */
715
716 list_for_each_entry(bss, &rdev->bss_list, list) {
717 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
718 continue;
719 if (bss->pub.channel != new->pub.channel)
720 continue;
721 if (bss->pub.scan_width != new->pub.scan_width)
722 continue;
723 if (rcu_access_pointer(bss->pub.beacon_ies))
724 continue;
725 ies = rcu_access_pointer(bss->pub.ies);
726 if (!ies)
727 continue;
728 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
729 if (!ie)
730 continue;
731 if (ssidlen && ie[1] != ssidlen)
732 continue;
733 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
734 continue;
735 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
736 list_del(&bss->hidden_list);
737 /* combine them */
738 list_add(&bss->hidden_list, &new->hidden_list);
739 bss->pub.hidden_beacon_bss = &new->pub;
740 new->refcount += bss->refcount;
741 rcu_assign_pointer(bss->pub.beacon_ies,
742 new->pub.beacon_ies);
743 }
744
745 return true;
746 }
747
748 /* Returned bss is reference counted and must be cleaned up appropriately. */
749 static struct cfg80211_internal_bss *
750 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
751 struct cfg80211_internal_bss *tmp,
752 bool signal_valid)
753 {
754 struct cfg80211_internal_bss *found = NULL;
755
756 if (WARN_ON(!tmp->pub.channel))
757 return NULL;
758
759 tmp->ts = jiffies;
760
761 spin_lock_bh(&rdev->bss_lock);
762
763 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
764 spin_unlock_bh(&rdev->bss_lock);
765 return NULL;
766 }
767
768 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
769
770 if (found) {
771 /* Update IEs */
772 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
773 const struct cfg80211_bss_ies *old;
774
775 old = rcu_access_pointer(found->pub.proberesp_ies);
776
777 rcu_assign_pointer(found->pub.proberesp_ies,
778 tmp->pub.proberesp_ies);
779 /* Override possible earlier Beacon frame IEs */
780 rcu_assign_pointer(found->pub.ies,
781 tmp->pub.proberesp_ies);
782 if (old)
783 kfree_rcu((struct cfg80211_bss_ies *)old,
784 rcu_head);
785 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
786 const struct cfg80211_bss_ies *old;
787 struct cfg80211_internal_bss *bss;
788
789 if (found->pub.hidden_beacon_bss &&
790 !list_empty(&found->hidden_list)) {
791 const struct cfg80211_bss_ies *f;
792
793 /*
794 * The found BSS struct is one of the probe
795 * response members of a group, but we're
796 * receiving a beacon (beacon_ies in the tmp
797 * bss is used). This can only mean that the
798 * AP changed its beacon from not having an
799 * SSID to showing it, which is confusing so
800 * drop this information.
801 */
802
803 f = rcu_access_pointer(tmp->pub.beacon_ies);
804 kfree_rcu((struct cfg80211_bss_ies *)f,
805 rcu_head);
806 goto drop;
807 }
808
809 old = rcu_access_pointer(found->pub.beacon_ies);
810
811 rcu_assign_pointer(found->pub.beacon_ies,
812 tmp->pub.beacon_ies);
813
814 /* Override IEs if they were from a beacon before */
815 if (old == rcu_access_pointer(found->pub.ies))
816 rcu_assign_pointer(found->pub.ies,
817 tmp->pub.beacon_ies);
818
819 /* Assign beacon IEs to all sub entries */
820 list_for_each_entry(bss, &found->hidden_list,
821 hidden_list) {
822 const struct cfg80211_bss_ies *ies;
823
824 ies = rcu_access_pointer(bss->pub.beacon_ies);
825 WARN_ON(ies != old);
826
827 rcu_assign_pointer(bss->pub.beacon_ies,
828 tmp->pub.beacon_ies);
829 }
830
831 if (old)
832 kfree_rcu((struct cfg80211_bss_ies *)old,
833 rcu_head);
834 }
835
836 found->pub.beacon_interval = tmp->pub.beacon_interval;
837 /*
838 * don't update the signal if beacon was heard on
839 * adjacent channel.
840 */
841 if (signal_valid)
842 found->pub.signal = tmp->pub.signal;
843 found->pub.capability = tmp->pub.capability;
844 found->ts = tmp->ts;
845 found->ts_boottime = tmp->ts_boottime;
846 } else {
847 struct cfg80211_internal_bss *new;
848 struct cfg80211_internal_bss *hidden;
849 struct cfg80211_bss_ies *ies;
850
851 /*
852 * create a copy -- the "res" variable that is passed in
853 * is allocated on the stack since it's not needed in the
854 * more common case of an update
855 */
856 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
857 GFP_ATOMIC);
858 if (!new) {
859 ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
860 if (ies)
861 kfree_rcu(ies, rcu_head);
862 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
863 if (ies)
864 kfree_rcu(ies, rcu_head);
865 goto drop;
866 }
867 memcpy(new, tmp, sizeof(*new));
868 new->refcount = 1;
869 INIT_LIST_HEAD(&new->hidden_list);
870
871 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
872 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
873 if (!hidden)
874 hidden = rb_find_bss(rdev, tmp,
875 BSS_CMP_HIDE_NUL);
876 if (hidden) {
877 new->pub.hidden_beacon_bss = &hidden->pub;
878 list_add(&new->hidden_list,
879 &hidden->hidden_list);
880 hidden->refcount++;
881 rcu_assign_pointer(new->pub.beacon_ies,
882 hidden->pub.beacon_ies);
883 }
884 } else {
885 /*
886 * Ok so we found a beacon, and don't have an entry. If
887 * it's a beacon with hidden SSID, we might be in for an
888 * expensive search for any probe responses that should
889 * be grouped with this beacon for updates ...
890 */
891 if (!cfg80211_combine_bsses(rdev, new)) {
892 kfree(new);
893 goto drop;
894 }
895 }
896
897 list_add_tail(&new->list, &rdev->bss_list);
898 rb_insert_bss(rdev, new);
899 found = new;
900 }
901
902 rdev->bss_generation++;
903 bss_ref_get(rdev, found);
904 spin_unlock_bh(&rdev->bss_lock);
905
906 return found;
907 drop:
908 spin_unlock_bh(&rdev->bss_lock);
909 return NULL;
910 }
911
912 static struct ieee80211_channel *
913 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
914 struct ieee80211_channel *channel)
915 {
916 const u8 *tmp;
917 u32 freq;
918 int channel_number = -1;
919
920 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
921 if (tmp && tmp[1] == 1) {
922 channel_number = tmp[2];
923 } else {
924 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
925 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
926 struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
927
928 channel_number = htop->primary_chan;
929 }
930 }
931
932 if (channel_number < 0)
933 return channel;
934
935 freq = ieee80211_channel_to_frequency(channel_number, channel->band);
936 channel = ieee80211_get_channel(wiphy, freq);
937 if (!channel)
938 return NULL;
939 if (channel->flags & IEEE80211_CHAN_DISABLED)
940 return NULL;
941 return channel;
942 }
943
944 /* Returned bss is reference counted and must be cleaned up appropriately. */
945 struct cfg80211_bss *
946 cfg80211_inform_bss_data(struct wiphy *wiphy,
947 struct cfg80211_inform_bss *data,
948 enum cfg80211_bss_frame_type ftype,
949 const u8 *bssid, u64 tsf, u16 capability,
950 u16 beacon_interval, const u8 *ie, size_t ielen,
951 gfp_t gfp)
952 {
953 struct cfg80211_bss_ies *ies;
954 struct ieee80211_channel *channel;
955 struct cfg80211_internal_bss tmp = {}, *res;
956 int bss_type;
957 bool signal_valid;
958
959 if (WARN_ON(!wiphy))
960 return NULL;
961
962 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
963 (data->signal < 0 || data->signal > 100)))
964 return NULL;
965
966 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan);
967 if (!channel)
968 return NULL;
969
970 memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
971 tmp.pub.channel = channel;
972 tmp.pub.scan_width = data->scan_width;
973 tmp.pub.signal = data->signal;
974 tmp.pub.beacon_interval = beacon_interval;
975 tmp.pub.capability = capability;
976 tmp.ts_boottime = data->boottime_ns;
977
978 /*
979 * If we do not know here whether the IEs are from a Beacon or Probe
980 * Response frame, we need to pick one of the options and only use it
981 * with the driver that does not provide the full Beacon/Probe Response
982 * frame. Use Beacon frame pointer to avoid indicating that this should
983 * override the IEs pointer should we have received an earlier
984 * indication of Probe Response data.
985 */
986 ies = kzalloc(sizeof(*ies) + ielen, gfp);
987 if (!ies)
988 return NULL;
989 ies->len = ielen;
990 ies->tsf = tsf;
991 ies->from_beacon = false;
992 memcpy(ies->data, ie, ielen);
993
994 switch (ftype) {
995 case CFG80211_BSS_FTYPE_BEACON:
996 ies->from_beacon = true;
997 /* fall through to assign */
998 case CFG80211_BSS_FTYPE_UNKNOWN:
999 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1000 break;
1001 case CFG80211_BSS_FTYPE_PRESP:
1002 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1003 break;
1004 }
1005 rcu_assign_pointer(tmp.pub.ies, ies);
1006
1007 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1008 wiphy->max_adj_channel_rssi_comp;
1009 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1010 if (!res)
1011 return NULL;
1012
1013 if (channel->band == NL80211_BAND_60GHZ) {
1014 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1015 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1016 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1017 regulatory_hint_found_beacon(wiphy, channel, gfp);
1018 } else {
1019 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1020 regulatory_hint_found_beacon(wiphy, channel, gfp);
1021 }
1022
1023 trace_cfg80211_return_bss(&res->pub);
1024 /* cfg80211_bss_update gives us a referenced result */
1025 return &res->pub;
1026 }
1027 EXPORT_SYMBOL(cfg80211_inform_bss_data);
1028
1029 /* cfg80211_inform_bss_width_frame helper */
1030 struct cfg80211_bss *
1031 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
1032 struct cfg80211_inform_bss *data,
1033 struct ieee80211_mgmt *mgmt, size_t len,
1034 gfp_t gfp)
1035
1036 {
1037 struct cfg80211_internal_bss tmp = {}, *res;
1038 struct cfg80211_bss_ies *ies;
1039 struct ieee80211_channel *channel;
1040 bool signal_valid;
1041 size_t ielen = len - offsetof(struct ieee80211_mgmt,
1042 u.probe_resp.variable);
1043 int bss_type;
1044
1045 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
1046 offsetof(struct ieee80211_mgmt, u.beacon.variable));
1047
1048 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
1049
1050 if (WARN_ON(!mgmt))
1051 return NULL;
1052
1053 if (WARN_ON(!wiphy))
1054 return NULL;
1055
1056 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1057 (data->signal < 0 || data->signal > 100)))
1058 return NULL;
1059
1060 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
1061 return NULL;
1062
1063 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
1064 ielen, data->chan);
1065 if (!channel)
1066 return NULL;
1067
1068 ies = kzalloc(sizeof(*ies) + ielen, gfp);
1069 if (!ies)
1070 return NULL;
1071 ies->len = ielen;
1072 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
1073 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
1074 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
1075
1076 if (ieee80211_is_probe_resp(mgmt->frame_control))
1077 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1078 else
1079 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1080 rcu_assign_pointer(tmp.pub.ies, ies);
1081
1082 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
1083 tmp.pub.channel = channel;
1084 tmp.pub.scan_width = data->scan_width;
1085 tmp.pub.signal = data->signal;
1086 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
1087 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
1088 tmp.ts_boottime = data->boottime_ns;
1089
1090 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1091 wiphy->max_adj_channel_rssi_comp;
1092 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1093 if (!res)
1094 return NULL;
1095
1096 if (channel->band == NL80211_BAND_60GHZ) {
1097 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1098 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1099 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1100 regulatory_hint_found_beacon(wiphy, channel, gfp);
1101 } else {
1102 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1103 regulatory_hint_found_beacon(wiphy, channel, gfp);
1104 }
1105
1106 trace_cfg80211_return_bss(&res->pub);
1107 /* cfg80211_bss_update gives us a referenced result */
1108 return &res->pub;
1109 }
1110 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1111
1112 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1113 {
1114 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1115 struct cfg80211_internal_bss *bss;
1116
1117 if (!pub)
1118 return;
1119
1120 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1121
1122 spin_lock_bh(&rdev->bss_lock);
1123 bss_ref_get(rdev, bss);
1124 spin_unlock_bh(&rdev->bss_lock);
1125 }
1126 EXPORT_SYMBOL(cfg80211_ref_bss);
1127
1128 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1129 {
1130 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1131 struct cfg80211_internal_bss *bss;
1132
1133 if (!pub)
1134 return;
1135
1136 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1137
1138 spin_lock_bh(&rdev->bss_lock);
1139 bss_ref_put(rdev, bss);
1140 spin_unlock_bh(&rdev->bss_lock);
1141 }
1142 EXPORT_SYMBOL(cfg80211_put_bss);
1143
1144 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1145 {
1146 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1147 struct cfg80211_internal_bss *bss;
1148
1149 if (WARN_ON(!pub))
1150 return;
1151
1152 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1153
1154 spin_lock_bh(&rdev->bss_lock);
1155 if (!list_empty(&bss->list)) {
1156 if (__cfg80211_unlink_bss(rdev, bss))
1157 rdev->bss_generation++;
1158 }
1159 spin_unlock_bh(&rdev->bss_lock);
1160 }
1161 EXPORT_SYMBOL(cfg80211_unlink_bss);
1162
1163 #ifdef CONFIG_CFG80211_WEXT
1164 static struct cfg80211_registered_device *
1165 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1166 {
1167 struct cfg80211_registered_device *rdev;
1168 struct net_device *dev;
1169
1170 ASSERT_RTNL();
1171
1172 dev = dev_get_by_index(net, ifindex);
1173 if (!dev)
1174 return ERR_PTR(-ENODEV);
1175 if (dev->ieee80211_ptr)
1176 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1177 else
1178 rdev = ERR_PTR(-ENODEV);
1179 dev_put(dev);
1180 return rdev;
1181 }
1182
1183 int cfg80211_wext_siwscan(struct net_device *dev,
1184 struct iw_request_info *info,
1185 union iwreq_data *wrqu, char *extra)
1186 {
1187 struct cfg80211_registered_device *rdev;
1188 struct wiphy *wiphy;
1189 struct iw_scan_req *wreq = NULL;
1190 struct cfg80211_scan_request *creq = NULL;
1191 int i, err, n_channels = 0;
1192 enum nl80211_band band;
1193
1194 if (!netif_running(dev))
1195 return -ENETDOWN;
1196
1197 if (wrqu->data.length == sizeof(struct iw_scan_req))
1198 wreq = (struct iw_scan_req *)extra;
1199
1200 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1201
1202 if (IS_ERR(rdev))
1203 return PTR_ERR(rdev);
1204
1205 if (rdev->scan_req || rdev->scan_msg) {
1206 err = -EBUSY;
1207 goto out;
1208 }
1209
1210 wiphy = &rdev->wiphy;
1211
1212 /* Determine number of channels, needed to allocate creq */
1213 if (wreq && wreq->num_channels)
1214 n_channels = wreq->num_channels;
1215 else
1216 n_channels = ieee80211_get_num_supported_channels(wiphy);
1217
1218 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1219 n_channels * sizeof(void *),
1220 GFP_ATOMIC);
1221 if (!creq) {
1222 err = -ENOMEM;
1223 goto out;
1224 }
1225
1226 creq->wiphy = wiphy;
1227 creq->wdev = dev->ieee80211_ptr;
1228 /* SSIDs come after channels */
1229 creq->ssids = (void *)&creq->channels[n_channels];
1230 creq->n_channels = n_channels;
1231 creq->n_ssids = 1;
1232 creq->scan_start = jiffies;
1233
1234 /* translate "Scan on frequencies" request */
1235 i = 0;
1236 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1237 int j;
1238
1239 if (!wiphy->bands[band])
1240 continue;
1241
1242 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1243 /* ignore disabled channels */
1244 if (wiphy->bands[band]->channels[j].flags &
1245 IEEE80211_CHAN_DISABLED)
1246 continue;
1247
1248 /* If we have a wireless request structure and the
1249 * wireless request specifies frequencies, then search
1250 * for the matching hardware channel.
1251 */
1252 if (wreq && wreq->num_channels) {
1253 int k;
1254 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1255 for (k = 0; k < wreq->num_channels; k++) {
1256 struct iw_freq *freq =
1257 &wreq->channel_list[k];
1258 int wext_freq =
1259 cfg80211_wext_freq(freq);
1260
1261 if (wext_freq == wiphy_freq)
1262 goto wext_freq_found;
1263 }
1264 goto wext_freq_not_found;
1265 }
1266
1267 wext_freq_found:
1268 creq->channels[i] = &wiphy->bands[band]->channels[j];
1269 i++;
1270 wext_freq_not_found: ;
1271 }
1272 }
1273 /* No channels found? */
1274 if (!i) {
1275 err = -EINVAL;
1276 goto out;
1277 }
1278
1279 /* Set real number of channels specified in creq->channels[] */
1280 creq->n_channels = i;
1281
1282 /* translate "Scan for SSID" request */
1283 if (wreq) {
1284 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1285 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1286 err = -EINVAL;
1287 goto out;
1288 }
1289 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1290 creq->ssids[0].ssid_len = wreq->essid_len;
1291 }
1292 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1293 creq->n_ssids = 0;
1294 }
1295
1296 for (i = 0; i < NUM_NL80211_BANDS; i++)
1297 if (wiphy->bands[i])
1298 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1299
1300 eth_broadcast_addr(creq->bssid);
1301
1302 rdev->scan_req = creq;
1303 err = rdev_scan(rdev, creq);
1304 if (err) {
1305 rdev->scan_req = NULL;
1306 /* creq will be freed below */
1307 } else {
1308 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1309 /* creq now owned by driver */
1310 creq = NULL;
1311 dev_hold(dev);
1312 }
1313 out:
1314 kfree(creq);
1315 return err;
1316 }
1317 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1318
1319 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1320 const struct cfg80211_bss_ies *ies,
1321 char *current_ev, char *end_buf)
1322 {
1323 const u8 *pos, *end, *next;
1324 struct iw_event iwe;
1325
1326 if (!ies)
1327 return current_ev;
1328
1329 /*
1330 * If needed, fragment the IEs buffer (at IE boundaries) into short
1331 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1332 */
1333 pos = ies->data;
1334 end = pos + ies->len;
1335
1336 while (end - pos > IW_GENERIC_IE_MAX) {
1337 next = pos + 2 + pos[1];
1338 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1339 next = next + 2 + next[1];
1340
1341 memset(&iwe, 0, sizeof(iwe));
1342 iwe.cmd = IWEVGENIE;
1343 iwe.u.data.length = next - pos;
1344 current_ev = iwe_stream_add_point_check(info, current_ev,
1345 end_buf, &iwe,
1346 (void *)pos);
1347 if (IS_ERR(current_ev))
1348 return current_ev;
1349 pos = next;
1350 }
1351
1352 if (end > pos) {
1353 memset(&iwe, 0, sizeof(iwe));
1354 iwe.cmd = IWEVGENIE;
1355 iwe.u.data.length = end - pos;
1356 current_ev = iwe_stream_add_point_check(info, current_ev,
1357 end_buf, &iwe,
1358 (void *)pos);
1359 if (IS_ERR(current_ev))
1360 return current_ev;
1361 }
1362
1363 return current_ev;
1364 }
1365
1366 static char *
1367 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1368 struct cfg80211_internal_bss *bss, char *current_ev,
1369 char *end_buf)
1370 {
1371 const struct cfg80211_bss_ies *ies;
1372 struct iw_event iwe;
1373 const u8 *ie;
1374 u8 buf[50];
1375 u8 *cfg, *p, *tmp;
1376 int rem, i, sig;
1377 bool ismesh = false;
1378
1379 memset(&iwe, 0, sizeof(iwe));
1380 iwe.cmd = SIOCGIWAP;
1381 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1382 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1383 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1384 IW_EV_ADDR_LEN);
1385 if (IS_ERR(current_ev))
1386 return current_ev;
1387
1388 memset(&iwe, 0, sizeof(iwe));
1389 iwe.cmd = SIOCGIWFREQ;
1390 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1391 iwe.u.freq.e = 0;
1392 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1393 IW_EV_FREQ_LEN);
1394 if (IS_ERR(current_ev))
1395 return current_ev;
1396
1397 memset(&iwe, 0, sizeof(iwe));
1398 iwe.cmd = SIOCGIWFREQ;
1399 iwe.u.freq.m = bss->pub.channel->center_freq;
1400 iwe.u.freq.e = 6;
1401 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1402 IW_EV_FREQ_LEN);
1403 if (IS_ERR(current_ev))
1404 return current_ev;
1405
1406 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1407 memset(&iwe, 0, sizeof(iwe));
1408 iwe.cmd = IWEVQUAL;
1409 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1410 IW_QUAL_NOISE_INVALID |
1411 IW_QUAL_QUAL_UPDATED;
1412 switch (wiphy->signal_type) {
1413 case CFG80211_SIGNAL_TYPE_MBM:
1414 sig = bss->pub.signal / 100;
1415 iwe.u.qual.level = sig;
1416 iwe.u.qual.updated |= IW_QUAL_DBM;
1417 if (sig < -110) /* rather bad */
1418 sig = -110;
1419 else if (sig > -40) /* perfect */
1420 sig = -40;
1421 /* will give a range of 0 .. 70 */
1422 iwe.u.qual.qual = sig + 110;
1423 break;
1424 case CFG80211_SIGNAL_TYPE_UNSPEC:
1425 iwe.u.qual.level = bss->pub.signal;
1426 /* will give range 0 .. 100 */
1427 iwe.u.qual.qual = bss->pub.signal;
1428 break;
1429 default:
1430 /* not reached */
1431 break;
1432 }
1433 current_ev = iwe_stream_add_event_check(info, current_ev,
1434 end_buf, &iwe,
1435 IW_EV_QUAL_LEN);
1436 if (IS_ERR(current_ev))
1437 return current_ev;
1438 }
1439
1440 memset(&iwe, 0, sizeof(iwe));
1441 iwe.cmd = SIOCGIWENCODE;
1442 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1443 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1444 else
1445 iwe.u.data.flags = IW_ENCODE_DISABLED;
1446 iwe.u.data.length = 0;
1447 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1448 &iwe, "");
1449 if (IS_ERR(current_ev))
1450 return current_ev;
1451
1452 rcu_read_lock();
1453 ies = rcu_dereference(bss->pub.ies);
1454 rem = ies->len;
1455 ie = ies->data;
1456
1457 while (rem >= 2) {
1458 /* invalid data */
1459 if (ie[1] > rem - 2)
1460 break;
1461
1462 switch (ie[0]) {
1463 case WLAN_EID_SSID:
1464 memset(&iwe, 0, sizeof(iwe));
1465 iwe.cmd = SIOCGIWESSID;
1466 iwe.u.data.length = ie[1];
1467 iwe.u.data.flags = 1;
1468 current_ev = iwe_stream_add_point_check(info,
1469 current_ev,
1470 end_buf, &iwe,
1471 (u8 *)ie + 2);
1472 if (IS_ERR(current_ev))
1473 goto unlock;
1474 break;
1475 case WLAN_EID_MESH_ID:
1476 memset(&iwe, 0, sizeof(iwe));
1477 iwe.cmd = SIOCGIWESSID;
1478 iwe.u.data.length = ie[1];
1479 iwe.u.data.flags = 1;
1480 current_ev = iwe_stream_add_point_check(info,
1481 current_ev,
1482 end_buf, &iwe,
1483 (u8 *)ie + 2);
1484 if (IS_ERR(current_ev))
1485 goto unlock;
1486 break;
1487 case WLAN_EID_MESH_CONFIG:
1488 ismesh = true;
1489 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1490 break;
1491 cfg = (u8 *)ie + 2;
1492 memset(&iwe, 0, sizeof(iwe));
1493 iwe.cmd = IWEVCUSTOM;
1494 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1495 "0x%02X", cfg[0]);
1496 iwe.u.data.length = strlen(buf);
1497 current_ev = iwe_stream_add_point_check(info,
1498 current_ev,
1499 end_buf,
1500 &iwe, buf);
1501 if (IS_ERR(current_ev))
1502 goto unlock;
1503 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1504 cfg[1]);
1505 iwe.u.data.length = strlen(buf);
1506 current_ev = iwe_stream_add_point_check(info,
1507 current_ev,
1508 end_buf,
1509 &iwe, buf);
1510 if (IS_ERR(current_ev))
1511 goto unlock;
1512 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1513 cfg[2]);
1514 iwe.u.data.length = strlen(buf);
1515 current_ev = iwe_stream_add_point_check(info,
1516 current_ev,
1517 end_buf,
1518 &iwe, buf);
1519 if (IS_ERR(current_ev))
1520 goto unlock;
1521 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1522 iwe.u.data.length = strlen(buf);
1523 current_ev = iwe_stream_add_point_check(info,
1524 current_ev,
1525 end_buf,
1526 &iwe, buf);
1527 if (IS_ERR(current_ev))
1528 goto unlock;
1529 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1530 iwe.u.data.length = strlen(buf);
1531 current_ev = iwe_stream_add_point_check(info,
1532 current_ev,
1533 end_buf,
1534 &iwe, buf);
1535 if (IS_ERR(current_ev))
1536 goto unlock;
1537 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1538 iwe.u.data.length = strlen(buf);
1539 current_ev = iwe_stream_add_point_check(info,
1540 current_ev,
1541 end_buf,
1542 &iwe, buf);
1543 if (IS_ERR(current_ev))
1544 goto unlock;
1545 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1546 iwe.u.data.length = strlen(buf);
1547 current_ev = iwe_stream_add_point_check(info,
1548 current_ev,
1549 end_buf,
1550 &iwe, buf);
1551 if (IS_ERR(current_ev))
1552 goto unlock;
1553 break;
1554 case WLAN_EID_SUPP_RATES:
1555 case WLAN_EID_EXT_SUPP_RATES:
1556 /* display all supported rates in readable format */
1557 p = current_ev + iwe_stream_lcp_len(info);
1558
1559 memset(&iwe, 0, sizeof(iwe));
1560 iwe.cmd = SIOCGIWRATE;
1561 /* Those two flags are ignored... */
1562 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1563
1564 for (i = 0; i < ie[1]; i++) {
1565 iwe.u.bitrate.value =
1566 ((ie[i + 2] & 0x7f) * 500000);
1567 tmp = p;
1568 p = iwe_stream_add_value(info, current_ev, p,
1569 end_buf, &iwe,
1570 IW_EV_PARAM_LEN);
1571 if (p == tmp) {
1572 current_ev = ERR_PTR(-E2BIG);
1573 goto unlock;
1574 }
1575 }
1576 current_ev = p;
1577 break;
1578 }
1579 rem -= ie[1] + 2;
1580 ie += ie[1] + 2;
1581 }
1582
1583 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1584 ismesh) {
1585 memset(&iwe, 0, sizeof(iwe));
1586 iwe.cmd = SIOCGIWMODE;
1587 if (ismesh)
1588 iwe.u.mode = IW_MODE_MESH;
1589 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1590 iwe.u.mode = IW_MODE_MASTER;
1591 else
1592 iwe.u.mode = IW_MODE_ADHOC;
1593 current_ev = iwe_stream_add_event_check(info, current_ev,
1594 end_buf, &iwe,
1595 IW_EV_UINT_LEN);
1596 if (IS_ERR(current_ev))
1597 goto unlock;
1598 }
1599
1600 memset(&iwe, 0, sizeof(iwe));
1601 iwe.cmd = IWEVCUSTOM;
1602 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1603 iwe.u.data.length = strlen(buf);
1604 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1605 &iwe, buf);
1606 if (IS_ERR(current_ev))
1607 goto unlock;
1608 memset(&iwe, 0, sizeof(iwe));
1609 iwe.cmd = IWEVCUSTOM;
1610 sprintf(buf, " Last beacon: %ums ago",
1611 elapsed_jiffies_msecs(bss->ts));
1612 iwe.u.data.length = strlen(buf);
1613 current_ev = iwe_stream_add_point_check(info, current_ev,
1614 end_buf, &iwe, buf);
1615 if (IS_ERR(current_ev))
1616 goto unlock;
1617
1618 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1619
1620 unlock:
1621 rcu_read_unlock();
1622 return current_ev;
1623 }
1624
1625
1626 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1627 struct iw_request_info *info,
1628 char *buf, size_t len)
1629 {
1630 char *current_ev = buf;
1631 char *end_buf = buf + len;
1632 struct cfg80211_internal_bss *bss;
1633 int err = 0;
1634
1635 spin_lock_bh(&rdev->bss_lock);
1636 cfg80211_bss_expire(rdev);
1637
1638 list_for_each_entry(bss, &rdev->bss_list, list) {
1639 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1640 err = -E2BIG;
1641 break;
1642 }
1643 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1644 current_ev, end_buf);
1645 if (IS_ERR(current_ev)) {
1646 err = PTR_ERR(current_ev);
1647 break;
1648 }
1649 }
1650 spin_unlock_bh(&rdev->bss_lock);
1651
1652 if (err)
1653 return err;
1654 return current_ev - buf;
1655 }
1656
1657
1658 int cfg80211_wext_giwscan(struct net_device *dev,
1659 struct iw_request_info *info,
1660 struct iw_point *data, char *extra)
1661 {
1662 struct cfg80211_registered_device *rdev;
1663 int res;
1664
1665 if (!netif_running(dev))
1666 return -ENETDOWN;
1667
1668 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1669
1670 if (IS_ERR(rdev))
1671 return PTR_ERR(rdev);
1672
1673 if (rdev->scan_req || rdev->scan_msg)
1674 return -EAGAIN;
1675
1676 res = ieee80211_scan_results(rdev, info, extra, data->length);
1677 data->length = 0;
1678 if (res >= 0) {
1679 data->length = res;
1680 res = 0;
1681 }
1682
1683 return res;
1684 }
1685 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1686 #endif
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