dfb53d19fd77b5df5e9d0aaa73ba73bd6c9a6dec
[linux-2.6.git] / net / wireless / scan.c
1 /*
2  * cfg80211 scan result handling
3  *
4  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5  */
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/netdevice.h>
9 #include <linux/wireless.h>
10 #include <linux/nl80211.h>
11 #include <linux/etherdevice.h>
12 #include <net/arp.h>
13 #include <net/cfg80211.h>
14 #include <net/iw_handler.h>
15 #include "core.h"
16 #include "nl80211.h"
17
18 #define IEEE80211_SCAN_RESULT_EXPIRE    (10 * HZ)
19
20 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
21 {
22         struct net_device *dev;
23 #ifdef CONFIG_WIRELESS_EXT
24         union iwreq_data wrqu;
25 #endif
26
27         dev = dev_get_by_index(&init_net, request->ifidx);
28         if (!dev)
29                 goto out;
30
31         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
32         wiphy_to_dev(request->wiphy)->scan_req = NULL;
33
34         if (aborted)
35                 nl80211_send_scan_aborted(wiphy_to_dev(request->wiphy), dev);
36         else
37                 nl80211_send_scan_done(wiphy_to_dev(request->wiphy), dev);
38
39 #ifdef CONFIG_WIRELESS_EXT
40         if (!aborted) {
41                 memset(&wrqu, 0, sizeof(wrqu));
42
43                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
44         }
45 #endif
46
47         dev_put(dev);
48
49  out:
50         kfree(request);
51 }
52 EXPORT_SYMBOL(cfg80211_scan_done);
53
54 static void bss_release(struct kref *ref)
55 {
56         struct cfg80211_internal_bss *bss;
57
58         bss = container_of(ref, struct cfg80211_internal_bss, ref);
59         if (bss->pub.free_priv)
60                 bss->pub.free_priv(&bss->pub);
61
62         if (bss->ies_allocated)
63                 kfree(bss->pub.information_elements);
64
65         kfree(bss);
66 }
67
68 /* must hold dev->bss_lock! */
69 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
70                       unsigned long age_secs)
71 {
72         struct cfg80211_internal_bss *bss;
73         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
74
75         list_for_each_entry(bss, &dev->bss_list, list) {
76                 bss->ts -= age_jiffies;
77         }
78 }
79
80 /* must hold dev->bss_lock! */
81 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
82 {
83         struct cfg80211_internal_bss *bss, *tmp;
84         bool expired = false;
85
86         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
87                 if (bss->hold ||
88                     !time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
89                         continue;
90                 list_del(&bss->list);
91                 rb_erase(&bss->rbn, &dev->bss_tree);
92                 kref_put(&bss->ref, bss_release);
93                 expired = true;
94         }
95
96         if (expired)
97                 dev->bss_generation++;
98 }
99
100 static u8 *find_ie(u8 num, u8 *ies, size_t len)
101 {
102         while (len > 2 && ies[0] != num) {
103                 len -= ies[1] + 2;
104                 ies += ies[1] + 2;
105         }
106         if (len < 2)
107                 return NULL;
108         if (len < 2 + ies[1])
109                 return NULL;
110         return ies;
111 }
112
113 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
114 {
115         const u8 *ie1 = find_ie(num, ies1, len1);
116         const u8 *ie2 = find_ie(num, ies2, len2);
117         int r;
118
119         if (!ie1 && !ie2)
120                 return 0;
121         if (!ie1)
122                 return -1;
123
124         r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
125         if (r == 0 && ie1[1] != ie2[1])
126                 return ie2[1] - ie1[1];
127         return r;
128 }
129
130 static bool is_bss(struct cfg80211_bss *a,
131                    const u8 *bssid,
132                    const u8 *ssid, size_t ssid_len)
133 {
134         const u8 *ssidie;
135
136         if (bssid && compare_ether_addr(a->bssid, bssid))
137                 return false;
138
139         if (!ssid)
140                 return true;
141
142         ssidie = find_ie(WLAN_EID_SSID,
143                          a->information_elements,
144                          a->len_information_elements);
145         if (!ssidie)
146                 return false;
147         if (ssidie[1] != ssid_len)
148                 return false;
149         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
150 }
151
152 static bool is_mesh(struct cfg80211_bss *a,
153                     const u8 *meshid, size_t meshidlen,
154                     const u8 *meshcfg)
155 {
156         const u8 *ie;
157
158         if (!is_zero_ether_addr(a->bssid))
159                 return false;
160
161         ie = find_ie(WLAN_EID_MESH_ID,
162                      a->information_elements,
163                      a->len_information_elements);
164         if (!ie)
165                 return false;
166         if (ie[1] != meshidlen)
167                 return false;
168         if (memcmp(ie + 2, meshid, meshidlen))
169                 return false;
170
171         ie = find_ie(WLAN_EID_MESH_CONFIG,
172                      a->information_elements,
173                      a->len_information_elements);
174         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
175                 return false;
176
177         /*
178          * Ignore mesh capability (last two bytes of the IE) when
179          * comparing since that may differ between stations taking
180          * part in the same mesh.
181          */
182         return memcmp(ie + 2, meshcfg, IEEE80211_MESH_CONFIG_LEN - 2) == 0;
183 }
184
185 static int cmp_bss(struct cfg80211_bss *a,
186                    struct cfg80211_bss *b)
187 {
188         int r;
189
190         if (a->channel != b->channel)
191                 return b->channel->center_freq - a->channel->center_freq;
192
193         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
194         if (r)
195                 return r;
196
197         if (is_zero_ether_addr(a->bssid)) {
198                 r = cmp_ies(WLAN_EID_MESH_ID,
199                             a->information_elements,
200                             a->len_information_elements,
201                             b->information_elements,
202                             b->len_information_elements);
203                 if (r)
204                         return r;
205                 return cmp_ies(WLAN_EID_MESH_CONFIG,
206                                a->information_elements,
207                                a->len_information_elements,
208                                b->information_elements,
209                                b->len_information_elements);
210         }
211
212         return cmp_ies(WLAN_EID_SSID,
213                        a->information_elements,
214                        a->len_information_elements,
215                        b->information_elements,
216                        b->len_information_elements);
217 }
218
219 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
220                                       struct ieee80211_channel *channel,
221                                       const u8 *bssid,
222                                       const u8 *ssid, size_t ssid_len,
223                                       u16 capa_mask, u16 capa_val)
224 {
225         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
226         struct cfg80211_internal_bss *bss, *res = NULL;
227
228         spin_lock_bh(&dev->bss_lock);
229
230         list_for_each_entry(bss, &dev->bss_list, list) {
231                 if ((bss->pub.capability & capa_mask) != capa_val)
232                         continue;
233                 if (channel && bss->pub.channel != channel)
234                         continue;
235                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
236                         res = bss;
237                         kref_get(&res->ref);
238                         break;
239                 }
240         }
241
242         spin_unlock_bh(&dev->bss_lock);
243         if (!res)
244                 return NULL;
245         return &res->pub;
246 }
247 EXPORT_SYMBOL(cfg80211_get_bss);
248
249 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
250                                        struct ieee80211_channel *channel,
251                                        const u8 *meshid, size_t meshidlen,
252                                        const u8 *meshcfg)
253 {
254         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
255         struct cfg80211_internal_bss *bss, *res = NULL;
256
257         spin_lock_bh(&dev->bss_lock);
258
259         list_for_each_entry(bss, &dev->bss_list, list) {
260                 if (channel && bss->pub.channel != channel)
261                         continue;
262                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
263                         res = bss;
264                         kref_get(&res->ref);
265                         break;
266                 }
267         }
268
269         spin_unlock_bh(&dev->bss_lock);
270         if (!res)
271                 return NULL;
272         return &res->pub;
273 }
274 EXPORT_SYMBOL(cfg80211_get_mesh);
275
276
277 static void rb_insert_bss(struct cfg80211_registered_device *dev,
278                           struct cfg80211_internal_bss *bss)
279 {
280         struct rb_node **p = &dev->bss_tree.rb_node;
281         struct rb_node *parent = NULL;
282         struct cfg80211_internal_bss *tbss;
283         int cmp;
284
285         while (*p) {
286                 parent = *p;
287                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
288
289                 cmp = cmp_bss(&bss->pub, &tbss->pub);
290
291                 if (WARN_ON(!cmp)) {
292                         /* will sort of leak this BSS */
293                         return;
294                 }
295
296                 if (cmp < 0)
297                         p = &(*p)->rb_left;
298                 else
299                         p = &(*p)->rb_right;
300         }
301
302         rb_link_node(&bss->rbn, parent, p);
303         rb_insert_color(&bss->rbn, &dev->bss_tree);
304 }
305
306 static struct cfg80211_internal_bss *
307 rb_find_bss(struct cfg80211_registered_device *dev,
308             struct cfg80211_internal_bss *res)
309 {
310         struct rb_node *n = dev->bss_tree.rb_node;
311         struct cfg80211_internal_bss *bss;
312         int r;
313
314         while (n) {
315                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
316                 r = cmp_bss(&res->pub, &bss->pub);
317
318                 if (r == 0)
319                         return bss;
320                 else if (r < 0)
321                         n = n->rb_left;
322                 else
323                         n = n->rb_right;
324         }
325
326         return NULL;
327 }
328
329 static struct cfg80211_internal_bss *
330 cfg80211_bss_update(struct cfg80211_registered_device *dev,
331                     struct cfg80211_internal_bss *res,
332                     bool overwrite)
333 {
334         struct cfg80211_internal_bss *found = NULL;
335         const u8 *meshid, *meshcfg;
336
337         /*
338          * The reference to "res" is donated to this function.
339          */
340
341         if (WARN_ON(!res->pub.channel)) {
342                 kref_put(&res->ref, bss_release);
343                 return NULL;
344         }
345
346         res->ts = jiffies;
347
348         if (is_zero_ether_addr(res->pub.bssid)) {
349                 /* must be mesh, verify */
350                 meshid = find_ie(WLAN_EID_MESH_ID, res->pub.information_elements,
351                                  res->pub.len_information_elements);
352                 meshcfg = find_ie(WLAN_EID_MESH_CONFIG,
353                                   res->pub.information_elements,
354                                   res->pub.len_information_elements);
355                 if (!meshid || !meshcfg ||
356                     meshcfg[1] != IEEE80211_MESH_CONFIG_LEN) {
357                         /* bogus mesh */
358                         kref_put(&res->ref, bss_release);
359                         return NULL;
360                 }
361         }
362
363         spin_lock_bh(&dev->bss_lock);
364
365         found = rb_find_bss(dev, res);
366
367         if (found) {
368                 kref_get(&found->ref);
369                 found->pub.beacon_interval = res->pub.beacon_interval;
370                 found->pub.tsf = res->pub.tsf;
371                 found->pub.signal = res->pub.signal;
372                 found->pub.capability = res->pub.capability;
373                 found->ts = res->ts;
374
375                 /* overwrite IEs */
376                 if (overwrite) {
377                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
378                         size_t ielen = res->pub.len_information_elements;
379
380                         if (ksize(found) >= used + ielen) {
381                                 memcpy(found->pub.information_elements,
382                                        res->pub.information_elements, ielen);
383                                 found->pub.len_information_elements = ielen;
384                         } else {
385                                 u8 *ies = found->pub.information_elements;
386
387                                 if (found->ies_allocated) {
388                                         if (ksize(ies) < ielen)
389                                                 ies = krealloc(ies, ielen,
390                                                                GFP_ATOMIC);
391                                 } else
392                                         ies = kmalloc(ielen, GFP_ATOMIC);
393
394                                 if (ies) {
395                                         memcpy(ies, res->pub.information_elements, ielen);
396                                         found->ies_allocated = true;
397                                         found->pub.information_elements = ies;
398                                         found->pub.len_information_elements = ielen;
399                                 }
400                         }
401                 }
402
403                 kref_put(&res->ref, bss_release);
404         } else {
405                 /* this "consumes" the reference */
406                 list_add_tail(&res->list, &dev->bss_list);
407                 rb_insert_bss(dev, res);
408                 found = res;
409         }
410
411         dev->bss_generation++;
412         spin_unlock_bh(&dev->bss_lock);
413
414         kref_get(&found->ref);
415         return found;
416 }
417
418 struct cfg80211_bss*
419 cfg80211_inform_bss(struct wiphy *wiphy,
420                     struct ieee80211_channel *channel,
421                     const u8 *bssid,
422                     u64 timestamp, u16 capability, u16 beacon_interval,
423                     const u8 *ie, size_t ielen,
424                     s32 signal, gfp_t gfp)
425 {
426         struct cfg80211_internal_bss *res;
427         size_t privsz;
428
429         if (WARN_ON(!wiphy))
430                 return NULL;
431
432         privsz = wiphy->bss_priv_size;
433
434         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
435                         (signal < 0 || signal > 100)))
436                 return NULL;
437
438         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
439         if (!res)
440                 return NULL;
441
442         memcpy(res->pub.bssid, bssid, ETH_ALEN);
443         res->pub.channel = channel;
444         res->pub.signal = signal;
445         res->pub.tsf = timestamp;
446         res->pub.beacon_interval = beacon_interval;
447         res->pub.capability = capability;
448         /* point to after the private area */
449         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
450         memcpy(res->pub.information_elements, ie, ielen);
451         res->pub.len_information_elements = ielen;
452
453         kref_init(&res->ref);
454
455         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, 0);
456         if (!res)
457                 return NULL;
458
459         if (res->pub.capability & WLAN_CAPABILITY_ESS)
460                 regulatory_hint_found_beacon(wiphy, channel, gfp);
461
462         /* cfg80211_bss_update gives us a referenced result */
463         return &res->pub;
464 }
465 EXPORT_SYMBOL(cfg80211_inform_bss);
466
467 struct cfg80211_bss *
468 cfg80211_inform_bss_frame(struct wiphy *wiphy,
469                           struct ieee80211_channel *channel,
470                           struct ieee80211_mgmt *mgmt, size_t len,
471                           s32 signal, gfp_t gfp)
472 {
473         struct cfg80211_internal_bss *res;
474         size_t ielen = len - offsetof(struct ieee80211_mgmt,
475                                       u.probe_resp.variable);
476         bool overwrite;
477         size_t privsz = wiphy->bss_priv_size;
478
479         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
480                     (signal < 0 || signal > 100)))
481                 return NULL;
482
483         if (WARN_ON(!mgmt || !wiphy ||
484                     len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
485                 return NULL;
486
487         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
488         if (!res)
489                 return NULL;
490
491         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
492         res->pub.channel = channel;
493         res->pub.signal = signal;
494         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
495         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
496         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
497         /* point to after the private area */
498         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
499         memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
500         res->pub.len_information_elements = ielen;
501
502         kref_init(&res->ref);
503
504         overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
505
506         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
507         if (!res)
508                 return NULL;
509
510         if (res->pub.capability & WLAN_CAPABILITY_ESS)
511                 regulatory_hint_found_beacon(wiphy, channel, gfp);
512
513         /* cfg80211_bss_update gives us a referenced result */
514         return &res->pub;
515 }
516 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
517
518 void cfg80211_put_bss(struct cfg80211_bss *pub)
519 {
520         struct cfg80211_internal_bss *bss;
521
522         if (!pub)
523                 return;
524
525         bss = container_of(pub, struct cfg80211_internal_bss, pub);
526         kref_put(&bss->ref, bss_release);
527 }
528 EXPORT_SYMBOL(cfg80211_put_bss);
529
530 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
531 {
532         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
533         struct cfg80211_internal_bss *bss;
534
535         if (WARN_ON(!pub))
536                 return;
537
538         bss = container_of(pub, struct cfg80211_internal_bss, pub);
539
540         spin_lock_bh(&dev->bss_lock);
541
542         list_del(&bss->list);
543         rb_erase(&bss->rbn, &dev->bss_tree);
544
545         spin_unlock_bh(&dev->bss_lock);
546
547         kref_put(&bss->ref, bss_release);
548 }
549 EXPORT_SYMBOL(cfg80211_unlink_bss);
550
551 void cfg80211_hold_bss(struct cfg80211_bss *pub)
552 {
553         struct cfg80211_internal_bss *bss;
554
555         if (!pub)
556                 return;
557
558         bss = container_of(pub, struct cfg80211_internal_bss, pub);
559         bss->hold = true;
560 }
561 EXPORT_SYMBOL(cfg80211_hold_bss);
562
563 void cfg80211_unhold_bss(struct cfg80211_bss *pub)
564 {
565         struct cfg80211_internal_bss *bss;
566
567         if (!pub)
568                 return;
569
570         bss = container_of(pub, struct cfg80211_internal_bss, pub);
571         bss->hold = false;
572 }
573 EXPORT_SYMBOL(cfg80211_unhold_bss);
574
575 #ifdef CONFIG_WIRELESS_EXT
576 int cfg80211_wext_siwscan(struct net_device *dev,
577                           struct iw_request_info *info,
578                           union iwreq_data *wrqu, char *extra)
579 {
580         struct cfg80211_registered_device *rdev;
581         struct wiphy *wiphy;
582         struct iw_scan_req *wreq = NULL;
583         struct cfg80211_scan_request *creq;
584         int i, err, n_channels = 0;
585         enum ieee80211_band band;
586
587         if (!netif_running(dev))
588                 return -ENETDOWN;
589
590         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
591
592         if (IS_ERR(rdev))
593                 return PTR_ERR(rdev);
594
595         if (rdev->scan_req) {
596                 err = -EBUSY;
597                 goto out;
598         }
599
600         wiphy = &rdev->wiphy;
601
602         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
603                 if (wiphy->bands[band])
604                         n_channels += wiphy->bands[band]->n_channels;
605
606         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
607                        n_channels * sizeof(void *),
608                        GFP_ATOMIC);
609         if (!creq) {
610                 err = -ENOMEM;
611                 goto out;
612         }
613
614         creq->wiphy = wiphy;
615         creq->ifidx = dev->ifindex;
616         creq->ssids = (void *)(creq + 1);
617         creq->channels = (void *)(creq->ssids + 1);
618         creq->n_channels = n_channels;
619         creq->n_ssids = 1;
620
621         /* all channels */
622         i = 0;
623         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
624                 int j;
625                 if (!wiphy->bands[band])
626                         continue;
627                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
628                         creq->channels[i] = &wiphy->bands[band]->channels[j];
629                         i++;
630                 }
631         }
632
633         /* translate scan request */
634         if (wrqu->data.length == sizeof(struct iw_scan_req)) {
635                 wreq = (struct iw_scan_req *)extra;
636
637                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
638                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
639                                 return -EINVAL;
640                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
641                         creq->ssids[0].ssid_len = wreq->essid_len;
642                 }
643                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
644                         creq->n_ssids = 0;
645         }
646
647         rdev->scan_req = creq;
648         err = rdev->ops->scan(wiphy, dev, creq);
649         if (err) {
650                 rdev->scan_req = NULL;
651                 kfree(creq);
652         }
653  out:
654         cfg80211_put_dev(rdev);
655         return err;
656 }
657 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
658
659 static void ieee80211_scan_add_ies(struct iw_request_info *info,
660                                    struct cfg80211_bss *bss,
661                                    char **current_ev, char *end_buf)
662 {
663         u8 *pos, *end, *next;
664         struct iw_event iwe;
665
666         if (!bss->information_elements ||
667             !bss->len_information_elements)
668                 return;
669
670         /*
671          * If needed, fragment the IEs buffer (at IE boundaries) into short
672          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
673          */
674         pos = bss->information_elements;
675         end = pos + bss->len_information_elements;
676
677         while (end - pos > IW_GENERIC_IE_MAX) {
678                 next = pos + 2 + pos[1];
679                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
680                         next = next + 2 + next[1];
681
682                 memset(&iwe, 0, sizeof(iwe));
683                 iwe.cmd = IWEVGENIE;
684                 iwe.u.data.length = next - pos;
685                 *current_ev = iwe_stream_add_point(info, *current_ev,
686                                                    end_buf, &iwe, pos);
687
688                 pos = next;
689         }
690
691         if (end > pos) {
692                 memset(&iwe, 0, sizeof(iwe));
693                 iwe.cmd = IWEVGENIE;
694                 iwe.u.data.length = end - pos;
695                 *current_ev = iwe_stream_add_point(info, *current_ev,
696                                                    end_buf, &iwe, pos);
697         }
698 }
699
700 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
701 {
702         unsigned long end = jiffies;
703
704         if (end >= start)
705                 return jiffies_to_msecs(end - start);
706
707         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
708 }
709
710 static char *
711 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
712               struct cfg80211_internal_bss *bss, char *current_ev,
713               char *end_buf)
714 {
715         struct iw_event iwe;
716         u8 *buf, *cfg, *p;
717         u8 *ie = bss->pub.information_elements;
718         int rem = bss->pub.len_information_elements, i, sig;
719         bool ismesh = false;
720
721         memset(&iwe, 0, sizeof(iwe));
722         iwe.cmd = SIOCGIWAP;
723         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
724         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
725         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
726                                           IW_EV_ADDR_LEN);
727
728         memset(&iwe, 0, sizeof(iwe));
729         iwe.cmd = SIOCGIWFREQ;
730         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
731         iwe.u.freq.e = 0;
732         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
733                                           IW_EV_FREQ_LEN);
734
735         memset(&iwe, 0, sizeof(iwe));
736         iwe.cmd = SIOCGIWFREQ;
737         iwe.u.freq.m = bss->pub.channel->center_freq;
738         iwe.u.freq.e = 6;
739         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
740                                           IW_EV_FREQ_LEN);
741
742         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
743                 memset(&iwe, 0, sizeof(iwe));
744                 iwe.cmd = IWEVQUAL;
745                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
746                                      IW_QUAL_NOISE_INVALID |
747                                      IW_QUAL_QUAL_UPDATED;
748                 switch (wiphy->signal_type) {
749                 case CFG80211_SIGNAL_TYPE_MBM:
750                         sig = bss->pub.signal / 100;
751                         iwe.u.qual.level = sig;
752                         iwe.u.qual.updated |= IW_QUAL_DBM;
753                         if (sig < -110)         /* rather bad */
754                                 sig = -110;
755                         else if (sig > -40)     /* perfect */
756                                 sig = -40;
757                         /* will give a range of 0 .. 70 */
758                         iwe.u.qual.qual = sig + 110;
759                         break;
760                 case CFG80211_SIGNAL_TYPE_UNSPEC:
761                         iwe.u.qual.level = bss->pub.signal;
762                         /* will give range 0 .. 100 */
763                         iwe.u.qual.qual = bss->pub.signal;
764                         break;
765                 default:
766                         /* not reached */
767                         break;
768                 }
769                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
770                                                   &iwe, IW_EV_QUAL_LEN);
771         }
772
773         memset(&iwe, 0, sizeof(iwe));
774         iwe.cmd = SIOCGIWENCODE;
775         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
776                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
777         else
778                 iwe.u.data.flags = IW_ENCODE_DISABLED;
779         iwe.u.data.length = 0;
780         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
781                                           &iwe, "");
782
783         while (rem >= 2) {
784                 /* invalid data */
785                 if (ie[1] > rem - 2)
786                         break;
787
788                 switch (ie[0]) {
789                 case WLAN_EID_SSID:
790                         memset(&iwe, 0, sizeof(iwe));
791                         iwe.cmd = SIOCGIWESSID;
792                         iwe.u.data.length = ie[1];
793                         iwe.u.data.flags = 1;
794                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
795                                                           &iwe, ie + 2);
796                         break;
797                 case WLAN_EID_MESH_ID:
798                         memset(&iwe, 0, sizeof(iwe));
799                         iwe.cmd = SIOCGIWESSID;
800                         iwe.u.data.length = ie[1];
801                         iwe.u.data.flags = 1;
802                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
803                                                           &iwe, ie + 2);
804                         break;
805                 case WLAN_EID_MESH_CONFIG:
806                         ismesh = true;
807                         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
808                                 break;
809                         buf = kmalloc(50, GFP_ATOMIC);
810                         if (!buf)
811                                 break;
812                         cfg = ie + 2;
813                         memset(&iwe, 0, sizeof(iwe));
814                         iwe.cmd = IWEVCUSTOM;
815                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
816                         iwe.u.data.length = strlen(buf);
817                         current_ev = iwe_stream_add_point(info, current_ev,
818                                                           end_buf,
819                                                           &iwe, buf);
820                         sprintf(buf, "Path Selection Protocol ID: "
821                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
822                                                         cfg[4]);
823                         iwe.u.data.length = strlen(buf);
824                         current_ev = iwe_stream_add_point(info, current_ev,
825                                                           end_buf,
826                                                           &iwe, buf);
827                         sprintf(buf, "Path Selection Metric ID: "
828                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
829                                                         cfg[8]);
830                         iwe.u.data.length = strlen(buf);
831                         current_ev = iwe_stream_add_point(info, current_ev,
832                                                           end_buf,
833                                                           &iwe, buf);
834                         sprintf(buf, "Congestion Control Mode ID: "
835                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
836                                                         cfg[11], cfg[12]);
837                         iwe.u.data.length = strlen(buf);
838                         current_ev = iwe_stream_add_point(info, current_ev,
839                                                           end_buf,
840                                                           &iwe, buf);
841                         sprintf(buf, "Channel Precedence: "
842                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
843                                                         cfg[15], cfg[16]);
844                         iwe.u.data.length = strlen(buf);
845                         current_ev = iwe_stream_add_point(info, current_ev,
846                                                           end_buf,
847                                                           &iwe, buf);
848                         kfree(buf);
849                         break;
850                 case WLAN_EID_SUPP_RATES:
851                 case WLAN_EID_EXT_SUPP_RATES:
852                         /* display all supported rates in readable format */
853                         p = current_ev + iwe_stream_lcp_len(info);
854
855                         memset(&iwe, 0, sizeof(iwe));
856                         iwe.cmd = SIOCGIWRATE;
857                         /* Those two flags are ignored... */
858                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
859
860                         for (i = 0; i < ie[1]; i++) {
861                                 iwe.u.bitrate.value =
862                                         ((ie[i + 2] & 0x7f) * 500000);
863                                 p = iwe_stream_add_value(info, current_ev, p,
864                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
865                         }
866                         current_ev = p;
867                         break;
868                 }
869                 rem -= ie[1] + 2;
870                 ie += ie[1] + 2;
871         }
872
873         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
874             || ismesh) {
875                 memset(&iwe, 0, sizeof(iwe));
876                 iwe.cmd = SIOCGIWMODE;
877                 if (ismesh)
878                         iwe.u.mode = IW_MODE_MESH;
879                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
880                         iwe.u.mode = IW_MODE_MASTER;
881                 else
882                         iwe.u.mode = IW_MODE_ADHOC;
883                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
884                                                   &iwe, IW_EV_UINT_LEN);
885         }
886
887         buf = kmalloc(30, GFP_ATOMIC);
888         if (buf) {
889                 memset(&iwe, 0, sizeof(iwe));
890                 iwe.cmd = IWEVCUSTOM;
891                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
892                 iwe.u.data.length = strlen(buf);
893                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
894                                                   &iwe, buf);
895                 memset(&iwe, 0, sizeof(iwe));
896                 iwe.cmd = IWEVCUSTOM;
897                 sprintf(buf, " Last beacon: %ums ago",
898                         elapsed_jiffies_msecs(bss->ts));
899                 iwe.u.data.length = strlen(buf);
900                 current_ev = iwe_stream_add_point(info, current_ev,
901                                                   end_buf, &iwe, buf);
902                 kfree(buf);
903         }
904
905         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
906
907         return current_ev;
908 }
909
910
911 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
912                                   struct iw_request_info *info,
913                                   char *buf, size_t len)
914 {
915         char *current_ev = buf;
916         char *end_buf = buf + len;
917         struct cfg80211_internal_bss *bss;
918
919         spin_lock_bh(&dev->bss_lock);
920         cfg80211_bss_expire(dev);
921
922         list_for_each_entry(bss, &dev->bss_list, list) {
923                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
924                         spin_unlock_bh(&dev->bss_lock);
925                         return -E2BIG;
926                 }
927                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
928                                            current_ev, end_buf);
929         }
930         spin_unlock_bh(&dev->bss_lock);
931         return current_ev - buf;
932 }
933
934
935 int cfg80211_wext_giwscan(struct net_device *dev,
936                           struct iw_request_info *info,
937                           struct iw_point *data, char *extra)
938 {
939         struct cfg80211_registered_device *rdev;
940         int res;
941
942         if (!netif_running(dev))
943                 return -ENETDOWN;
944
945         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
946
947         if (IS_ERR(rdev))
948                 return PTR_ERR(rdev);
949
950         if (rdev->scan_req) {
951                 res = -EAGAIN;
952                 goto out;
953         }
954
955         res = ieee80211_scan_results(rdev, info, extra, data->length);
956         data->length = 0;
957         if (res >= 0) {
958                 data->length = res;
959                 res = 0;
960         }
961
962  out:
963         cfg80211_put_dev(rdev);
964         return res;
965 }
966 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
967 #endif