]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - net/wireless/scan.c
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
[mirror_ubuntu-bionic-kernel.git] / net / wireless / scan.c
1 /*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 * Copyright 2013-2014 Intel Mobile Communications GmbH
6 * Copyright 2016 Intel Deutschland GmbH
7 */
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/netdevice.h>
12 #include <linux/wireless.h>
13 #include <linux/nl80211.h>
14 #include <linux/etherdevice.h>
15 #include <net/arp.h>
16 #include <net/cfg80211.h>
17 #include <net/cfg80211-wext.h>
18 #include <net/iw_handler.h>
19 #include "core.h"
20 #include "nl80211.h"
21 #include "wext-compat.h"
22 #include "rdev-ops.h"
23
24 /**
25 * DOC: BSS tree/list structure
26 *
27 * At the top level, the BSS list is kept in both a list in each
28 * registered device (@bss_list) as well as an RB-tree for faster
29 * lookup. In the RB-tree, entries can be looked up using their
30 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
31 * for other BSSes.
32 *
33 * Due to the possibility of hidden SSIDs, there's a second level
34 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
35 * The hidden_list connects all BSSes belonging to a single AP
36 * that has a hidden SSID, and connects beacon and probe response
37 * entries. For a probe response entry for a hidden SSID, the
38 * hidden_beacon_bss pointer points to the BSS struct holding the
39 * beacon's information.
40 *
41 * Reference counting is done for all these references except for
42 * the hidden_list, so that a beacon BSS struct that is otherwise
43 * not referenced has one reference for being on the bss_list and
44 * one for each probe response entry that points to it using the
45 * hidden_beacon_bss pointer. When a BSS struct that has such a
46 * pointer is get/put, the refcount update is also propagated to
47 * the referenced struct, this ensure that it cannot get removed
48 * while somebody is using the probe response version.
49 *
50 * Note that the hidden_beacon_bss pointer never changes, due to
51 * the reference counting. Therefore, no locking is needed for
52 * it.
53 *
54 * Also note that the hidden_beacon_bss pointer is only relevant
55 * if the driver uses something other than the IEs, e.g. private
56 * data stored stored in the BSS struct, since the beacon IEs are
57 * also linked into the probe response struct.
58 */
59
60 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
61
62 static void bss_free(struct cfg80211_internal_bss *bss)
63 {
64 struct cfg80211_bss_ies *ies;
65
66 if (WARN_ON(atomic_read(&bss->hold)))
67 return;
68
69 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
70 if (ies && !bss->pub.hidden_beacon_bss)
71 kfree_rcu(ies, rcu_head);
72 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
73 if (ies)
74 kfree_rcu(ies, rcu_head);
75
76 /*
77 * This happens when the module is removed, it doesn't
78 * really matter any more save for completeness
79 */
80 if (!list_empty(&bss->hidden_list))
81 list_del(&bss->hidden_list);
82
83 kfree(bss);
84 }
85
86 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
87 struct cfg80211_internal_bss *bss)
88 {
89 lockdep_assert_held(&rdev->bss_lock);
90
91 bss->refcount++;
92 if (bss->pub.hidden_beacon_bss) {
93 bss = container_of(bss->pub.hidden_beacon_bss,
94 struct cfg80211_internal_bss,
95 pub);
96 bss->refcount++;
97 }
98 }
99
100 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
101 struct cfg80211_internal_bss *bss)
102 {
103 lockdep_assert_held(&rdev->bss_lock);
104
105 if (bss->pub.hidden_beacon_bss) {
106 struct cfg80211_internal_bss *hbss;
107 hbss = container_of(bss->pub.hidden_beacon_bss,
108 struct cfg80211_internal_bss,
109 pub);
110 hbss->refcount--;
111 if (hbss->refcount == 0)
112 bss_free(hbss);
113 }
114 bss->refcount--;
115 if (bss->refcount == 0)
116 bss_free(bss);
117 }
118
119 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
120 struct cfg80211_internal_bss *bss)
121 {
122 lockdep_assert_held(&rdev->bss_lock);
123
124 if (!list_empty(&bss->hidden_list)) {
125 /*
126 * don't remove the beacon entry if it has
127 * probe responses associated with it
128 */
129 if (!bss->pub.hidden_beacon_bss)
130 return false;
131 /*
132 * if it's a probe response entry break its
133 * link to the other entries in the group
134 */
135 list_del_init(&bss->hidden_list);
136 }
137
138 list_del_init(&bss->list);
139 rb_erase(&bss->rbn, &rdev->bss_tree);
140 bss_ref_put(rdev, bss);
141 return true;
142 }
143
144 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
145 unsigned long expire_time)
146 {
147 struct cfg80211_internal_bss *bss, *tmp;
148 bool expired = false;
149
150 lockdep_assert_held(&rdev->bss_lock);
151
152 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
153 if (atomic_read(&bss->hold))
154 continue;
155 if (!time_after(expire_time, bss->ts))
156 continue;
157
158 if (__cfg80211_unlink_bss(rdev, bss))
159 expired = true;
160 }
161
162 if (expired)
163 rdev->bss_generation++;
164 }
165
166 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
167 bool send_message)
168 {
169 struct cfg80211_scan_request *request;
170 struct wireless_dev *wdev;
171 struct sk_buff *msg;
172 #ifdef CONFIG_CFG80211_WEXT
173 union iwreq_data wrqu;
174 #endif
175
176 ASSERT_RTNL();
177
178 if (rdev->scan_msg) {
179 nl80211_send_scan_result(rdev, rdev->scan_msg);
180 rdev->scan_msg = NULL;
181 return;
182 }
183
184 request = rdev->scan_req;
185 if (!request)
186 return;
187
188 wdev = request->wdev;
189
190 /*
191 * This must be before sending the other events!
192 * Otherwise, wpa_supplicant gets completely confused with
193 * wext events.
194 */
195 if (wdev->netdev)
196 cfg80211_sme_scan_done(wdev->netdev);
197
198 if (!request->info.aborted &&
199 request->flags & NL80211_SCAN_FLAG_FLUSH) {
200 /* flush entries from previous scans */
201 spin_lock_bh(&rdev->bss_lock);
202 __cfg80211_bss_expire(rdev, request->scan_start);
203 spin_unlock_bh(&rdev->bss_lock);
204 }
205
206 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
207
208 #ifdef CONFIG_CFG80211_WEXT
209 if (wdev->netdev && !request->info.aborted) {
210 memset(&wrqu, 0, sizeof(wrqu));
211
212 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
213 }
214 #endif
215
216 if (wdev->netdev)
217 dev_put(wdev->netdev);
218
219 rdev->scan_req = NULL;
220 kfree(request);
221
222 if (!send_message)
223 rdev->scan_msg = msg;
224 else
225 nl80211_send_scan_result(rdev, msg);
226 }
227
228 void __cfg80211_scan_done(struct work_struct *wk)
229 {
230 struct cfg80211_registered_device *rdev;
231
232 rdev = container_of(wk, struct cfg80211_registered_device,
233 scan_done_wk);
234
235 rtnl_lock();
236 ___cfg80211_scan_done(rdev, true);
237 rtnl_unlock();
238 }
239
240 void cfg80211_scan_done(struct cfg80211_scan_request *request,
241 struct cfg80211_scan_info *info)
242 {
243 trace_cfg80211_scan_done(request, info);
244 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);
245
246 request->info = *info;
247 request->notified = true;
248 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
249 }
250 EXPORT_SYMBOL(cfg80211_scan_done);
251
252 void __cfg80211_sched_scan_results(struct work_struct *wk)
253 {
254 struct cfg80211_registered_device *rdev;
255 struct cfg80211_sched_scan_request *request;
256
257 rdev = container_of(wk, struct cfg80211_registered_device,
258 sched_scan_results_wk);
259
260 rtnl_lock();
261
262 request = rtnl_dereference(rdev->sched_scan_req);
263
264 /* we don't have sched_scan_req anymore if the scan is stopping */
265 if (request) {
266 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
267 /* flush entries from previous scans */
268 spin_lock_bh(&rdev->bss_lock);
269 __cfg80211_bss_expire(rdev, request->scan_start);
270 spin_unlock_bh(&rdev->bss_lock);
271 request->scan_start = jiffies;
272 }
273 nl80211_send_sched_scan_results(rdev, request->dev);
274 }
275
276 rtnl_unlock();
277 }
278
279 void cfg80211_sched_scan_results(struct wiphy *wiphy)
280 {
281 trace_cfg80211_sched_scan_results(wiphy);
282 /* ignore if we're not scanning */
283
284 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req))
285 queue_work(cfg80211_wq,
286 &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
287 }
288 EXPORT_SYMBOL(cfg80211_sched_scan_results);
289
290 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
291 {
292 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
293
294 ASSERT_RTNL();
295
296 trace_cfg80211_sched_scan_stopped(wiphy);
297
298 __cfg80211_stop_sched_scan(rdev, true);
299 }
300 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);
301
302 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
303 {
304 rtnl_lock();
305 cfg80211_sched_scan_stopped_rtnl(wiphy);
306 rtnl_unlock();
307 }
308 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
309
310 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
311 bool driver_initiated)
312 {
313 struct cfg80211_sched_scan_request *sched_scan_req;
314 struct net_device *dev;
315
316 ASSERT_RTNL();
317
318 if (!rdev->sched_scan_req)
319 return -ENOENT;
320
321 sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
322 dev = sched_scan_req->dev;
323
324 if (!driver_initiated) {
325 int err = rdev_sched_scan_stop(rdev, dev);
326 if (err)
327 return err;
328 }
329
330 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
331
332 RCU_INIT_POINTER(rdev->sched_scan_req, NULL);
333 kfree_rcu(sched_scan_req, rcu_head);
334
335 return 0;
336 }
337
338 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
339 unsigned long age_secs)
340 {
341 struct cfg80211_internal_bss *bss;
342 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
343
344 spin_lock_bh(&rdev->bss_lock);
345 list_for_each_entry(bss, &rdev->bss_list, list)
346 bss->ts -= age_jiffies;
347 spin_unlock_bh(&rdev->bss_lock);
348 }
349
350 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
351 {
352 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
353 }
354
355 const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,
356 const u8 *match, int match_len,
357 int match_offset)
358 {
359 /* match_offset can't be smaller than 2, unless match_len is
360 * zero, in which case match_offset must be zero as well.
361 */
362 if (WARN_ON((match_len && match_offset < 2) ||
363 (!match_len && match_offset)))
364 return NULL;
365
366 while (len >= 2 && len >= ies[1] + 2) {
367 if ((ies[0] == eid) &&
368 (ies[1] + 2 >= match_offset + match_len) &&
369 !memcmp(ies + match_offset, match, match_len))
370 return ies;
371
372 len -= ies[1] + 2;
373 ies += ies[1] + 2;
374 }
375
376 return NULL;
377 }
378 EXPORT_SYMBOL(cfg80211_find_ie_match);
379
380 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
381 const u8 *ies, int len)
382 {
383 const u8 *ie;
384 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
385 int match_len = (oui_type < 0) ? 3 : sizeof(match);
386
387 if (WARN_ON(oui_type > 0xff))
388 return NULL;
389
390 ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
391 match, match_len, 2);
392
393 if (ie && (ie[1] < 4))
394 return NULL;
395
396 return ie;
397 }
398 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
399
400 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
401 const u8 *ssid, size_t ssid_len)
402 {
403 const struct cfg80211_bss_ies *ies;
404 const u8 *ssidie;
405
406 if (bssid && !ether_addr_equal(a->bssid, bssid))
407 return false;
408
409 if (!ssid)
410 return true;
411
412 ies = rcu_access_pointer(a->ies);
413 if (!ies)
414 return false;
415 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
416 if (!ssidie)
417 return false;
418 if (ssidie[1] != ssid_len)
419 return false;
420 return memcmp(ssidie + 2, ssid, ssid_len) == 0;
421 }
422
423 /**
424 * enum bss_compare_mode - BSS compare mode
425 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
426 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
427 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
428 */
429 enum bss_compare_mode {
430 BSS_CMP_REGULAR,
431 BSS_CMP_HIDE_ZLEN,
432 BSS_CMP_HIDE_NUL,
433 };
434
435 static int cmp_bss(struct cfg80211_bss *a,
436 struct cfg80211_bss *b,
437 enum bss_compare_mode mode)
438 {
439 const struct cfg80211_bss_ies *a_ies, *b_ies;
440 const u8 *ie1 = NULL;
441 const u8 *ie2 = NULL;
442 int i, r;
443
444 if (a->channel != b->channel)
445 return b->channel->center_freq - a->channel->center_freq;
446
447 a_ies = rcu_access_pointer(a->ies);
448 if (!a_ies)
449 return -1;
450 b_ies = rcu_access_pointer(b->ies);
451 if (!b_ies)
452 return 1;
453
454 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
455 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
456 a_ies->data, a_ies->len);
457 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
458 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
459 b_ies->data, b_ies->len);
460 if (ie1 && ie2) {
461 int mesh_id_cmp;
462
463 if (ie1[1] == ie2[1])
464 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
465 else
466 mesh_id_cmp = ie2[1] - ie1[1];
467
468 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
469 a_ies->data, a_ies->len);
470 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
471 b_ies->data, b_ies->len);
472 if (ie1 && ie2) {
473 if (mesh_id_cmp)
474 return mesh_id_cmp;
475 if (ie1[1] != ie2[1])
476 return ie2[1] - ie1[1];
477 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
478 }
479 }
480
481 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
482 if (r)
483 return r;
484
485 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
486 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
487
488 if (!ie1 && !ie2)
489 return 0;
490
491 /*
492 * Note that with "hide_ssid", the function returns a match if
493 * the already-present BSS ("b") is a hidden SSID beacon for
494 * the new BSS ("a").
495 */
496
497 /* sort missing IE before (left of) present IE */
498 if (!ie1)
499 return -1;
500 if (!ie2)
501 return 1;
502
503 switch (mode) {
504 case BSS_CMP_HIDE_ZLEN:
505 /*
506 * In ZLEN mode we assume the BSS entry we're
507 * looking for has a zero-length SSID. So if
508 * the one we're looking at right now has that,
509 * return 0. Otherwise, return the difference
510 * in length, but since we're looking for the
511 * 0-length it's really equivalent to returning
512 * the length of the one we're looking at.
513 *
514 * No content comparison is needed as we assume
515 * the content length is zero.
516 */
517 return ie2[1];
518 case BSS_CMP_REGULAR:
519 default:
520 /* sort by length first, then by contents */
521 if (ie1[1] != ie2[1])
522 return ie2[1] - ie1[1];
523 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
524 case BSS_CMP_HIDE_NUL:
525 if (ie1[1] != ie2[1])
526 return ie2[1] - ie1[1];
527 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
528 for (i = 0; i < ie2[1]; i++)
529 if (ie2[i + 2])
530 return -1;
531 return 0;
532 }
533 }
534
535 static bool cfg80211_bss_type_match(u16 capability,
536 enum nl80211_band band,
537 enum ieee80211_bss_type bss_type)
538 {
539 bool ret = true;
540 u16 mask, val;
541
542 if (bss_type == IEEE80211_BSS_TYPE_ANY)
543 return ret;
544
545 if (band == NL80211_BAND_60GHZ) {
546 mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
547 switch (bss_type) {
548 case IEEE80211_BSS_TYPE_ESS:
549 val = WLAN_CAPABILITY_DMG_TYPE_AP;
550 break;
551 case IEEE80211_BSS_TYPE_PBSS:
552 val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
553 break;
554 case IEEE80211_BSS_TYPE_IBSS:
555 val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
556 break;
557 default:
558 return false;
559 }
560 } else {
561 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
562 switch (bss_type) {
563 case IEEE80211_BSS_TYPE_ESS:
564 val = WLAN_CAPABILITY_ESS;
565 break;
566 case IEEE80211_BSS_TYPE_IBSS:
567 val = WLAN_CAPABILITY_IBSS;
568 break;
569 case IEEE80211_BSS_TYPE_MBSS:
570 val = 0;
571 break;
572 default:
573 return false;
574 }
575 }
576
577 ret = ((capability & mask) == val);
578 return ret;
579 }
580
581 /* Returned bss is reference counted and must be cleaned up appropriately. */
582 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
583 struct ieee80211_channel *channel,
584 const u8 *bssid,
585 const u8 *ssid, size_t ssid_len,
586 enum ieee80211_bss_type bss_type,
587 enum ieee80211_privacy privacy)
588 {
589 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
590 struct cfg80211_internal_bss *bss, *res = NULL;
591 unsigned long now = jiffies;
592 int bss_privacy;
593
594 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
595 privacy);
596
597 spin_lock_bh(&rdev->bss_lock);
598
599 list_for_each_entry(bss, &rdev->bss_list, list) {
600 if (!cfg80211_bss_type_match(bss->pub.capability,
601 bss->pub.channel->band, bss_type))
602 continue;
603
604 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
605 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
606 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
607 continue;
608 if (channel && bss->pub.channel != channel)
609 continue;
610 if (!is_valid_ether_addr(bss->pub.bssid))
611 continue;
612 /* Don't get expired BSS structs */
613 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
614 !atomic_read(&bss->hold))
615 continue;
616 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
617 res = bss;
618 bss_ref_get(rdev, res);
619 break;
620 }
621 }
622
623 spin_unlock_bh(&rdev->bss_lock);
624 if (!res)
625 return NULL;
626 trace_cfg80211_return_bss(&res->pub);
627 return &res->pub;
628 }
629 EXPORT_SYMBOL(cfg80211_get_bss);
630
631 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
632 struct cfg80211_internal_bss *bss)
633 {
634 struct rb_node **p = &rdev->bss_tree.rb_node;
635 struct rb_node *parent = NULL;
636 struct cfg80211_internal_bss *tbss;
637 int cmp;
638
639 while (*p) {
640 parent = *p;
641 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
642
643 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
644
645 if (WARN_ON(!cmp)) {
646 /* will sort of leak this BSS */
647 return;
648 }
649
650 if (cmp < 0)
651 p = &(*p)->rb_left;
652 else
653 p = &(*p)->rb_right;
654 }
655
656 rb_link_node(&bss->rbn, parent, p);
657 rb_insert_color(&bss->rbn, &rdev->bss_tree);
658 }
659
660 static struct cfg80211_internal_bss *
661 rb_find_bss(struct cfg80211_registered_device *rdev,
662 struct cfg80211_internal_bss *res,
663 enum bss_compare_mode mode)
664 {
665 struct rb_node *n = rdev->bss_tree.rb_node;
666 struct cfg80211_internal_bss *bss;
667 int r;
668
669 while (n) {
670 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
671 r = cmp_bss(&res->pub, &bss->pub, mode);
672
673 if (r == 0)
674 return bss;
675 else if (r < 0)
676 n = n->rb_left;
677 else
678 n = n->rb_right;
679 }
680
681 return NULL;
682 }
683
684 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
685 struct cfg80211_internal_bss *new)
686 {
687 const struct cfg80211_bss_ies *ies;
688 struct cfg80211_internal_bss *bss;
689 const u8 *ie;
690 int i, ssidlen;
691 u8 fold = 0;
692
693 ies = rcu_access_pointer(new->pub.beacon_ies);
694 if (WARN_ON(!ies))
695 return false;
696
697 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
698 if (!ie) {
699 /* nothing to do */
700 return true;
701 }
702
703 ssidlen = ie[1];
704 for (i = 0; i < ssidlen; i++)
705 fold |= ie[2 + i];
706
707 if (fold) {
708 /* not a hidden SSID */
709 return true;
710 }
711
712 /* This is the bad part ... */
713
714 list_for_each_entry(bss, &rdev->bss_list, list) {
715 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
716 continue;
717 if (bss->pub.channel != new->pub.channel)
718 continue;
719 if (bss->pub.scan_width != new->pub.scan_width)
720 continue;
721 if (rcu_access_pointer(bss->pub.beacon_ies))
722 continue;
723 ies = rcu_access_pointer(bss->pub.ies);
724 if (!ies)
725 continue;
726 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
727 if (!ie)
728 continue;
729 if (ssidlen && ie[1] != ssidlen)
730 continue;
731 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
732 continue;
733 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
734 list_del(&bss->hidden_list);
735 /* combine them */
736 list_add(&bss->hidden_list, &new->hidden_list);
737 bss->pub.hidden_beacon_bss = &new->pub;
738 new->refcount += bss->refcount;
739 rcu_assign_pointer(bss->pub.beacon_ies,
740 new->pub.beacon_ies);
741 }
742
743 return true;
744 }
745
746 /* Returned bss is reference counted and must be cleaned up appropriately. */
747 static struct cfg80211_internal_bss *
748 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
749 struct cfg80211_internal_bss *tmp,
750 bool signal_valid)
751 {
752 struct cfg80211_internal_bss *found = NULL;
753
754 if (WARN_ON(!tmp->pub.channel))
755 return NULL;
756
757 tmp->ts = jiffies;
758
759 spin_lock_bh(&rdev->bss_lock);
760
761 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
762 spin_unlock_bh(&rdev->bss_lock);
763 return NULL;
764 }
765
766 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
767
768 if (found) {
769 /* Update IEs */
770 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
771 const struct cfg80211_bss_ies *old;
772
773 old = rcu_access_pointer(found->pub.proberesp_ies);
774
775 rcu_assign_pointer(found->pub.proberesp_ies,
776 tmp->pub.proberesp_ies);
777 /* Override possible earlier Beacon frame IEs */
778 rcu_assign_pointer(found->pub.ies,
779 tmp->pub.proberesp_ies);
780 if (old)
781 kfree_rcu((struct cfg80211_bss_ies *)old,
782 rcu_head);
783 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
784 const struct cfg80211_bss_ies *old;
785 struct cfg80211_internal_bss *bss;
786
787 if (found->pub.hidden_beacon_bss &&
788 !list_empty(&found->hidden_list)) {
789 const struct cfg80211_bss_ies *f;
790
791 /*
792 * The found BSS struct is one of the probe
793 * response members of a group, but we're
794 * receiving a beacon (beacon_ies in the tmp
795 * bss is used). This can only mean that the
796 * AP changed its beacon from not having an
797 * SSID to showing it, which is confusing so
798 * drop this information.
799 */
800
801 f = rcu_access_pointer(tmp->pub.beacon_ies);
802 kfree_rcu((struct cfg80211_bss_ies *)f,
803 rcu_head);
804 goto drop;
805 }
806
807 old = rcu_access_pointer(found->pub.beacon_ies);
808
809 rcu_assign_pointer(found->pub.beacon_ies,
810 tmp->pub.beacon_ies);
811
812 /* Override IEs if they were from a beacon before */
813 if (old == rcu_access_pointer(found->pub.ies))
814 rcu_assign_pointer(found->pub.ies,
815 tmp->pub.beacon_ies);
816
817 /* Assign beacon IEs to all sub entries */
818 list_for_each_entry(bss, &found->hidden_list,
819 hidden_list) {
820 const struct cfg80211_bss_ies *ies;
821
822 ies = rcu_access_pointer(bss->pub.beacon_ies);
823 WARN_ON(ies != old);
824
825 rcu_assign_pointer(bss->pub.beacon_ies,
826 tmp->pub.beacon_ies);
827 }
828
829 if (old)
830 kfree_rcu((struct cfg80211_bss_ies *)old,
831 rcu_head);
832 }
833
834 found->pub.beacon_interval = tmp->pub.beacon_interval;
835 /*
836 * don't update the signal if beacon was heard on
837 * adjacent channel.
838 */
839 if (signal_valid)
840 found->pub.signal = tmp->pub.signal;
841 found->pub.capability = tmp->pub.capability;
842 found->ts = tmp->ts;
843 found->ts_boottime = tmp->ts_boottime;
844 found->parent_tsf = tmp->parent_tsf;
845 ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
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 tmp.parent_tsf = data->parent_tsf;
1090 ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1091
1092 signal_valid = abs(data->chan->center_freq - channel->center_freq) <=
1093 wiphy->max_adj_channel_rssi_comp;
1094 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid);
1095 if (!res)
1096 return NULL;
1097
1098 if (channel->band == NL80211_BAND_60GHZ) {
1099 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1100 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1101 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1102 regulatory_hint_found_beacon(wiphy, channel, gfp);
1103 } else {
1104 if (res->pub.capability & WLAN_CAPABILITY_ESS)
1105 regulatory_hint_found_beacon(wiphy, channel, gfp);
1106 }
1107
1108 trace_cfg80211_return_bss(&res->pub);
1109 /* cfg80211_bss_update gives us a referenced result */
1110 return &res->pub;
1111 }
1112 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
1113
1114 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1115 {
1116 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1117 struct cfg80211_internal_bss *bss;
1118
1119 if (!pub)
1120 return;
1121
1122 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1123
1124 spin_lock_bh(&rdev->bss_lock);
1125 bss_ref_get(rdev, bss);
1126 spin_unlock_bh(&rdev->bss_lock);
1127 }
1128 EXPORT_SYMBOL(cfg80211_ref_bss);
1129
1130 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1131 {
1132 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1133 struct cfg80211_internal_bss *bss;
1134
1135 if (!pub)
1136 return;
1137
1138 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1139
1140 spin_lock_bh(&rdev->bss_lock);
1141 bss_ref_put(rdev, bss);
1142 spin_unlock_bh(&rdev->bss_lock);
1143 }
1144 EXPORT_SYMBOL(cfg80211_put_bss);
1145
1146 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1147 {
1148 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1149 struct cfg80211_internal_bss *bss;
1150
1151 if (WARN_ON(!pub))
1152 return;
1153
1154 bss = container_of(pub, struct cfg80211_internal_bss, pub);
1155
1156 spin_lock_bh(&rdev->bss_lock);
1157 if (!list_empty(&bss->list)) {
1158 if (__cfg80211_unlink_bss(rdev, bss))
1159 rdev->bss_generation++;
1160 }
1161 spin_unlock_bh(&rdev->bss_lock);
1162 }
1163 EXPORT_SYMBOL(cfg80211_unlink_bss);
1164
1165 #ifdef CONFIG_CFG80211_WEXT
1166 static struct cfg80211_registered_device *
1167 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1168 {
1169 struct cfg80211_registered_device *rdev;
1170 struct net_device *dev;
1171
1172 ASSERT_RTNL();
1173
1174 dev = dev_get_by_index(net, ifindex);
1175 if (!dev)
1176 return ERR_PTR(-ENODEV);
1177 if (dev->ieee80211_ptr)
1178 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
1179 else
1180 rdev = ERR_PTR(-ENODEV);
1181 dev_put(dev);
1182 return rdev;
1183 }
1184
1185 int cfg80211_wext_siwscan(struct net_device *dev,
1186 struct iw_request_info *info,
1187 union iwreq_data *wrqu, char *extra)
1188 {
1189 struct cfg80211_registered_device *rdev;
1190 struct wiphy *wiphy;
1191 struct iw_scan_req *wreq = NULL;
1192 struct cfg80211_scan_request *creq = NULL;
1193 int i, err, n_channels = 0;
1194 enum nl80211_band band;
1195
1196 if (!netif_running(dev))
1197 return -ENETDOWN;
1198
1199 if (wrqu->data.length == sizeof(struct iw_scan_req))
1200 wreq = (struct iw_scan_req *)extra;
1201
1202 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1203
1204 if (IS_ERR(rdev))
1205 return PTR_ERR(rdev);
1206
1207 if (rdev->scan_req || rdev->scan_msg) {
1208 err = -EBUSY;
1209 goto out;
1210 }
1211
1212 wiphy = &rdev->wiphy;
1213
1214 /* Determine number of channels, needed to allocate creq */
1215 if (wreq && wreq->num_channels)
1216 n_channels = wreq->num_channels;
1217 else
1218 n_channels = ieee80211_get_num_supported_channels(wiphy);
1219
1220 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1221 n_channels * sizeof(void *),
1222 GFP_ATOMIC);
1223 if (!creq) {
1224 err = -ENOMEM;
1225 goto out;
1226 }
1227
1228 creq->wiphy = wiphy;
1229 creq->wdev = dev->ieee80211_ptr;
1230 /* SSIDs come after channels */
1231 creq->ssids = (void *)&creq->channels[n_channels];
1232 creq->n_channels = n_channels;
1233 creq->n_ssids = 1;
1234 creq->scan_start = jiffies;
1235
1236 /* translate "Scan on frequencies" request */
1237 i = 0;
1238 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1239 int j;
1240
1241 if (!wiphy->bands[band])
1242 continue;
1243
1244 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1245 /* ignore disabled channels */
1246 if (wiphy->bands[band]->channels[j].flags &
1247 IEEE80211_CHAN_DISABLED)
1248 continue;
1249
1250 /* If we have a wireless request structure and the
1251 * wireless request specifies frequencies, then search
1252 * for the matching hardware channel.
1253 */
1254 if (wreq && wreq->num_channels) {
1255 int k;
1256 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1257 for (k = 0; k < wreq->num_channels; k++) {
1258 struct iw_freq *freq =
1259 &wreq->channel_list[k];
1260 int wext_freq =
1261 cfg80211_wext_freq(freq);
1262
1263 if (wext_freq == wiphy_freq)
1264 goto wext_freq_found;
1265 }
1266 goto wext_freq_not_found;
1267 }
1268
1269 wext_freq_found:
1270 creq->channels[i] = &wiphy->bands[band]->channels[j];
1271 i++;
1272 wext_freq_not_found: ;
1273 }
1274 }
1275 /* No channels found? */
1276 if (!i) {
1277 err = -EINVAL;
1278 goto out;
1279 }
1280
1281 /* Set real number of channels specified in creq->channels[] */
1282 creq->n_channels = i;
1283
1284 /* translate "Scan for SSID" request */
1285 if (wreq) {
1286 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1287 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1288 err = -EINVAL;
1289 goto out;
1290 }
1291 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1292 creq->ssids[0].ssid_len = wreq->essid_len;
1293 }
1294 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1295 creq->n_ssids = 0;
1296 }
1297
1298 for (i = 0; i < NUM_NL80211_BANDS; i++)
1299 if (wiphy->bands[i])
1300 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1301
1302 eth_broadcast_addr(creq->bssid);
1303
1304 rdev->scan_req = creq;
1305 err = rdev_scan(rdev, creq);
1306 if (err) {
1307 rdev->scan_req = NULL;
1308 /* creq will be freed below */
1309 } else {
1310 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1311 /* creq now owned by driver */
1312 creq = NULL;
1313 dev_hold(dev);
1314 }
1315 out:
1316 kfree(creq);
1317 return err;
1318 }
1319 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
1320
1321 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
1322 const struct cfg80211_bss_ies *ies,
1323 char *current_ev, char *end_buf)
1324 {
1325 const u8 *pos, *end, *next;
1326 struct iw_event iwe;
1327
1328 if (!ies)
1329 return current_ev;
1330
1331 /*
1332 * If needed, fragment the IEs buffer (at IE boundaries) into short
1333 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1334 */
1335 pos = ies->data;
1336 end = pos + ies->len;
1337
1338 while (end - pos > IW_GENERIC_IE_MAX) {
1339 next = pos + 2 + pos[1];
1340 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1341 next = next + 2 + next[1];
1342
1343 memset(&iwe, 0, sizeof(iwe));
1344 iwe.cmd = IWEVGENIE;
1345 iwe.u.data.length = next - pos;
1346 current_ev = iwe_stream_add_point_check(info, current_ev,
1347 end_buf, &iwe,
1348 (void *)pos);
1349 if (IS_ERR(current_ev))
1350 return current_ev;
1351 pos = next;
1352 }
1353
1354 if (end > pos) {
1355 memset(&iwe, 0, sizeof(iwe));
1356 iwe.cmd = IWEVGENIE;
1357 iwe.u.data.length = end - pos;
1358 current_ev = iwe_stream_add_point_check(info, current_ev,
1359 end_buf, &iwe,
1360 (void *)pos);
1361 if (IS_ERR(current_ev))
1362 return current_ev;
1363 }
1364
1365 return current_ev;
1366 }
1367
1368 static char *
1369 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1370 struct cfg80211_internal_bss *bss, char *current_ev,
1371 char *end_buf)
1372 {
1373 const struct cfg80211_bss_ies *ies;
1374 struct iw_event iwe;
1375 const u8 *ie;
1376 u8 buf[50];
1377 u8 *cfg, *p, *tmp;
1378 int rem, i, sig;
1379 bool ismesh = false;
1380
1381 memset(&iwe, 0, sizeof(iwe));
1382 iwe.cmd = SIOCGIWAP;
1383 iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1384 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1385 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1386 IW_EV_ADDR_LEN);
1387 if (IS_ERR(current_ev))
1388 return current_ev;
1389
1390 memset(&iwe, 0, sizeof(iwe));
1391 iwe.cmd = SIOCGIWFREQ;
1392 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1393 iwe.u.freq.e = 0;
1394 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1395 IW_EV_FREQ_LEN);
1396 if (IS_ERR(current_ev))
1397 return current_ev;
1398
1399 memset(&iwe, 0, sizeof(iwe));
1400 iwe.cmd = SIOCGIWFREQ;
1401 iwe.u.freq.m = bss->pub.channel->center_freq;
1402 iwe.u.freq.e = 6;
1403 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
1404 IW_EV_FREQ_LEN);
1405 if (IS_ERR(current_ev))
1406 return current_ev;
1407
1408 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1409 memset(&iwe, 0, sizeof(iwe));
1410 iwe.cmd = IWEVQUAL;
1411 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1412 IW_QUAL_NOISE_INVALID |
1413 IW_QUAL_QUAL_UPDATED;
1414 switch (wiphy->signal_type) {
1415 case CFG80211_SIGNAL_TYPE_MBM:
1416 sig = bss->pub.signal / 100;
1417 iwe.u.qual.level = sig;
1418 iwe.u.qual.updated |= IW_QUAL_DBM;
1419 if (sig < -110) /* rather bad */
1420 sig = -110;
1421 else if (sig > -40) /* perfect */
1422 sig = -40;
1423 /* will give a range of 0 .. 70 */
1424 iwe.u.qual.qual = sig + 110;
1425 break;
1426 case CFG80211_SIGNAL_TYPE_UNSPEC:
1427 iwe.u.qual.level = bss->pub.signal;
1428 /* will give range 0 .. 100 */
1429 iwe.u.qual.qual = bss->pub.signal;
1430 break;
1431 default:
1432 /* not reached */
1433 break;
1434 }
1435 current_ev = iwe_stream_add_event_check(info, current_ev,
1436 end_buf, &iwe,
1437 IW_EV_QUAL_LEN);
1438 if (IS_ERR(current_ev))
1439 return current_ev;
1440 }
1441
1442 memset(&iwe, 0, sizeof(iwe));
1443 iwe.cmd = SIOCGIWENCODE;
1444 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1445 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1446 else
1447 iwe.u.data.flags = IW_ENCODE_DISABLED;
1448 iwe.u.data.length = 0;
1449 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1450 &iwe, "");
1451 if (IS_ERR(current_ev))
1452 return current_ev;
1453
1454 rcu_read_lock();
1455 ies = rcu_dereference(bss->pub.ies);
1456 rem = ies->len;
1457 ie = ies->data;
1458
1459 while (rem >= 2) {
1460 /* invalid data */
1461 if (ie[1] > rem - 2)
1462 break;
1463
1464 switch (ie[0]) {
1465 case WLAN_EID_SSID:
1466 memset(&iwe, 0, sizeof(iwe));
1467 iwe.cmd = SIOCGIWESSID;
1468 iwe.u.data.length = ie[1];
1469 iwe.u.data.flags = 1;
1470 current_ev = iwe_stream_add_point_check(info,
1471 current_ev,
1472 end_buf, &iwe,
1473 (u8 *)ie + 2);
1474 if (IS_ERR(current_ev))
1475 goto unlock;
1476 break;
1477 case WLAN_EID_MESH_ID:
1478 memset(&iwe, 0, sizeof(iwe));
1479 iwe.cmd = SIOCGIWESSID;
1480 iwe.u.data.length = ie[1];
1481 iwe.u.data.flags = 1;
1482 current_ev = iwe_stream_add_point_check(info,
1483 current_ev,
1484 end_buf, &iwe,
1485 (u8 *)ie + 2);
1486 if (IS_ERR(current_ev))
1487 goto unlock;
1488 break;
1489 case WLAN_EID_MESH_CONFIG:
1490 ismesh = true;
1491 if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1492 break;
1493 cfg = (u8 *)ie + 2;
1494 memset(&iwe, 0, sizeof(iwe));
1495 iwe.cmd = IWEVCUSTOM;
1496 sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1497 "0x%02X", cfg[0]);
1498 iwe.u.data.length = strlen(buf);
1499 current_ev = iwe_stream_add_point_check(info,
1500 current_ev,
1501 end_buf,
1502 &iwe, buf);
1503 if (IS_ERR(current_ev))
1504 goto unlock;
1505 sprintf(buf, "Path Selection Metric ID: 0x%02X",
1506 cfg[1]);
1507 iwe.u.data.length = strlen(buf);
1508 current_ev = iwe_stream_add_point_check(info,
1509 current_ev,
1510 end_buf,
1511 &iwe, buf);
1512 if (IS_ERR(current_ev))
1513 goto unlock;
1514 sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1515 cfg[2]);
1516 iwe.u.data.length = strlen(buf);
1517 current_ev = iwe_stream_add_point_check(info,
1518 current_ev,
1519 end_buf,
1520 &iwe, buf);
1521 if (IS_ERR(current_ev))
1522 goto unlock;
1523 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1524 iwe.u.data.length = strlen(buf);
1525 current_ev = iwe_stream_add_point_check(info,
1526 current_ev,
1527 end_buf,
1528 &iwe, buf);
1529 if (IS_ERR(current_ev))
1530 goto unlock;
1531 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1532 iwe.u.data.length = strlen(buf);
1533 current_ev = iwe_stream_add_point_check(info,
1534 current_ev,
1535 end_buf,
1536 &iwe, buf);
1537 if (IS_ERR(current_ev))
1538 goto unlock;
1539 sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1540 iwe.u.data.length = strlen(buf);
1541 current_ev = iwe_stream_add_point_check(info,
1542 current_ev,
1543 end_buf,
1544 &iwe, buf);
1545 if (IS_ERR(current_ev))
1546 goto unlock;
1547 sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1548 iwe.u.data.length = strlen(buf);
1549 current_ev = iwe_stream_add_point_check(info,
1550 current_ev,
1551 end_buf,
1552 &iwe, buf);
1553 if (IS_ERR(current_ev))
1554 goto unlock;
1555 break;
1556 case WLAN_EID_SUPP_RATES:
1557 case WLAN_EID_EXT_SUPP_RATES:
1558 /* display all supported rates in readable format */
1559 p = current_ev + iwe_stream_lcp_len(info);
1560
1561 memset(&iwe, 0, sizeof(iwe));
1562 iwe.cmd = SIOCGIWRATE;
1563 /* Those two flags are ignored... */
1564 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1565
1566 for (i = 0; i < ie[1]; i++) {
1567 iwe.u.bitrate.value =
1568 ((ie[i + 2] & 0x7f) * 500000);
1569 tmp = p;
1570 p = iwe_stream_add_value(info, current_ev, p,
1571 end_buf, &iwe,
1572 IW_EV_PARAM_LEN);
1573 if (p == tmp) {
1574 current_ev = ERR_PTR(-E2BIG);
1575 goto unlock;
1576 }
1577 }
1578 current_ev = p;
1579 break;
1580 }
1581 rem -= ie[1] + 2;
1582 ie += ie[1] + 2;
1583 }
1584
1585 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1586 ismesh) {
1587 memset(&iwe, 0, sizeof(iwe));
1588 iwe.cmd = SIOCGIWMODE;
1589 if (ismesh)
1590 iwe.u.mode = IW_MODE_MESH;
1591 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1592 iwe.u.mode = IW_MODE_MASTER;
1593 else
1594 iwe.u.mode = IW_MODE_ADHOC;
1595 current_ev = iwe_stream_add_event_check(info, current_ev,
1596 end_buf, &iwe,
1597 IW_EV_UINT_LEN);
1598 if (IS_ERR(current_ev))
1599 goto unlock;
1600 }
1601
1602 memset(&iwe, 0, sizeof(iwe));
1603 iwe.cmd = IWEVCUSTOM;
1604 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1605 iwe.u.data.length = strlen(buf);
1606 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
1607 &iwe, buf);
1608 if (IS_ERR(current_ev))
1609 goto unlock;
1610 memset(&iwe, 0, sizeof(iwe));
1611 iwe.cmd = IWEVCUSTOM;
1612 sprintf(buf, " Last beacon: %ums ago",
1613 elapsed_jiffies_msecs(bss->ts));
1614 iwe.u.data.length = strlen(buf);
1615 current_ev = iwe_stream_add_point_check(info, current_ev,
1616 end_buf, &iwe, buf);
1617 if (IS_ERR(current_ev))
1618 goto unlock;
1619
1620 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
1621
1622 unlock:
1623 rcu_read_unlock();
1624 return current_ev;
1625 }
1626
1627
1628 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
1629 struct iw_request_info *info,
1630 char *buf, size_t len)
1631 {
1632 char *current_ev = buf;
1633 char *end_buf = buf + len;
1634 struct cfg80211_internal_bss *bss;
1635 int err = 0;
1636
1637 spin_lock_bh(&rdev->bss_lock);
1638 cfg80211_bss_expire(rdev);
1639
1640 list_for_each_entry(bss, &rdev->bss_list, list) {
1641 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1642 err = -E2BIG;
1643 break;
1644 }
1645 current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
1646 current_ev, end_buf);
1647 if (IS_ERR(current_ev)) {
1648 err = PTR_ERR(current_ev);
1649 break;
1650 }
1651 }
1652 spin_unlock_bh(&rdev->bss_lock);
1653
1654 if (err)
1655 return err;
1656 return current_ev - buf;
1657 }
1658
1659
1660 int cfg80211_wext_giwscan(struct net_device *dev,
1661 struct iw_request_info *info,
1662 struct iw_point *data, char *extra)
1663 {
1664 struct cfg80211_registered_device *rdev;
1665 int res;
1666
1667 if (!netif_running(dev))
1668 return -ENETDOWN;
1669
1670 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1671
1672 if (IS_ERR(rdev))
1673 return PTR_ERR(rdev);
1674
1675 if (rdev->scan_req || rdev->scan_msg)
1676 return -EAGAIN;
1677
1678 res = ieee80211_scan_results(rdev, info, extra, data->length);
1679 data->length = 0;
1680 if (res >= 0) {
1681 data->length = res;
1682 res = 0;
1683 }
1684
1685 return res;
1686 }
1687 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
1688 #endif