cfg80211: minimal error handling for wext-compat freq scanning
[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 #include "wext-compat.h"
18
19 #define IEEE80211_SCAN_RESULT_EXPIRE    (15 * HZ)
20
21 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
22 {
23         struct cfg80211_scan_request *request;
24         struct net_device *dev;
25 #ifdef CONFIG_WIRELESS_EXT
26         union iwreq_data wrqu;
27 #endif
28
29         ASSERT_RDEV_LOCK(rdev);
30
31         request = rdev->scan_req;
32
33         if (!request)
34                 return;
35
36         dev = request->dev;
37
38         /*
39          * This must be before sending the other events!
40          * Otherwise, wpa_supplicant gets completely confused with
41          * wext events.
42          */
43         cfg80211_sme_scan_done(dev);
44
45         if (request->aborted)
46                 nl80211_send_scan_aborted(rdev, dev);
47         else
48                 nl80211_send_scan_done(rdev, dev);
49
50 #ifdef CONFIG_WIRELESS_EXT
51         if (!request->aborted) {
52                 memset(&wrqu, 0, sizeof(wrqu));
53
54                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
55         }
56 #endif
57
58         dev_put(dev);
59
60         rdev->scan_req = NULL;
61
62         /*
63          * OK. If this is invoked with "leak" then we can't
64          * free this ... but we've cleaned it up anyway. The
65          * driver failed to call the scan_done callback, so
66          * all bets are off, it might still be trying to use
67          * the scan request or not ... if it accesses the dev
68          * in there (it shouldn't anyway) then it may crash.
69          */
70         if (!leak)
71                 kfree(request);
72 }
73
74 void __cfg80211_scan_done(struct work_struct *wk)
75 {
76         struct cfg80211_registered_device *rdev;
77
78         rdev = container_of(wk, struct cfg80211_registered_device,
79                             scan_done_wk);
80
81         cfg80211_lock_rdev(rdev);
82         ___cfg80211_scan_done(rdev, false);
83         cfg80211_unlock_rdev(rdev);
84 }
85
86 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
87 {
88         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
89
90         request->aborted = aborted;
91         schedule_work(&wiphy_to_dev(request->wiphy)->scan_done_wk);
92 }
93 EXPORT_SYMBOL(cfg80211_scan_done);
94
95 static void bss_release(struct kref *ref)
96 {
97         struct cfg80211_internal_bss *bss;
98
99         bss = container_of(ref, struct cfg80211_internal_bss, ref);
100         if (bss->pub.free_priv)
101                 bss->pub.free_priv(&bss->pub);
102
103         if (bss->ies_allocated)
104                 kfree(bss->pub.information_elements);
105
106         BUG_ON(atomic_read(&bss->hold));
107
108         kfree(bss);
109 }
110
111 /* must hold dev->bss_lock! */
112 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
113                       unsigned long age_secs)
114 {
115         struct cfg80211_internal_bss *bss;
116         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
117
118         list_for_each_entry(bss, &dev->bss_list, list) {
119                 bss->ts -= age_jiffies;
120         }
121 }
122
123 /* must hold dev->bss_lock! */
124 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
125 {
126         struct cfg80211_internal_bss *bss, *tmp;
127         bool expired = false;
128
129         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
130                 if (atomic_read(&bss->hold))
131                         continue;
132                 if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
133                         continue;
134                 list_del(&bss->list);
135                 rb_erase(&bss->rbn, &dev->bss_tree);
136                 kref_put(&bss->ref, bss_release);
137                 expired = true;
138         }
139
140         if (expired)
141                 dev->bss_generation++;
142 }
143
144 static u8 *find_ie(u8 num, u8 *ies, int len)
145 {
146         while (len > 2 && ies[0] != num) {
147                 len -= ies[1] + 2;
148                 ies += ies[1] + 2;
149         }
150         if (len < 2)
151                 return NULL;
152         if (len < 2 + ies[1])
153                 return NULL;
154         return ies;
155 }
156
157 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
158 {
159         const u8 *ie1 = find_ie(num, ies1, len1);
160         const u8 *ie2 = find_ie(num, ies2, len2);
161         int r;
162
163         if (!ie1 && !ie2)
164                 return 0;
165         if (!ie1 || !ie2)
166                 return -1;
167
168         r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
169         if (r == 0 && ie1[1] != ie2[1])
170                 return ie2[1] - ie1[1];
171         return r;
172 }
173
174 static bool is_bss(struct cfg80211_bss *a,
175                    const u8 *bssid,
176                    const u8 *ssid, size_t ssid_len)
177 {
178         const u8 *ssidie;
179
180         if (bssid && compare_ether_addr(a->bssid, bssid))
181                 return false;
182
183         if (!ssid)
184                 return true;
185
186         ssidie = find_ie(WLAN_EID_SSID,
187                          a->information_elements,
188                          a->len_information_elements);
189         if (!ssidie)
190                 return false;
191         if (ssidie[1] != ssid_len)
192                 return false;
193         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
194 }
195
196 static bool is_mesh(struct cfg80211_bss *a,
197                     const u8 *meshid, size_t meshidlen,
198                     const u8 *meshcfg)
199 {
200         const u8 *ie;
201
202         if (!is_zero_ether_addr(a->bssid))
203                 return false;
204
205         ie = find_ie(WLAN_EID_MESH_ID,
206                      a->information_elements,
207                      a->len_information_elements);
208         if (!ie)
209                 return false;
210         if (ie[1] != meshidlen)
211                 return false;
212         if (memcmp(ie + 2, meshid, meshidlen))
213                 return false;
214
215         ie = find_ie(WLAN_EID_MESH_CONFIG,
216                      a->information_elements,
217                      a->len_information_elements);
218         if (!ie)
219                 return false;
220         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
221                 return false;
222
223         /*
224          * Ignore mesh capability (last two bytes of the IE) when
225          * comparing since that may differ between stations taking
226          * part in the same mesh.
227          */
228         return memcmp(ie + 2, meshcfg, IEEE80211_MESH_CONFIG_LEN - 2) == 0;
229 }
230
231 static int cmp_bss(struct cfg80211_bss *a,
232                    struct cfg80211_bss *b)
233 {
234         int r;
235
236         if (a->channel != b->channel)
237                 return b->channel->center_freq - a->channel->center_freq;
238
239         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
240         if (r)
241                 return r;
242
243         if (is_zero_ether_addr(a->bssid)) {
244                 r = cmp_ies(WLAN_EID_MESH_ID,
245                             a->information_elements,
246                             a->len_information_elements,
247                             b->information_elements,
248                             b->len_information_elements);
249                 if (r)
250                         return r;
251                 return cmp_ies(WLAN_EID_MESH_CONFIG,
252                                a->information_elements,
253                                a->len_information_elements,
254                                b->information_elements,
255                                b->len_information_elements);
256         }
257
258         return cmp_ies(WLAN_EID_SSID,
259                        a->information_elements,
260                        a->len_information_elements,
261                        b->information_elements,
262                        b->len_information_elements);
263 }
264
265 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
266                                       struct ieee80211_channel *channel,
267                                       const u8 *bssid,
268                                       const u8 *ssid, size_t ssid_len,
269                                       u16 capa_mask, u16 capa_val)
270 {
271         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
272         struct cfg80211_internal_bss *bss, *res = NULL;
273
274         spin_lock_bh(&dev->bss_lock);
275
276         list_for_each_entry(bss, &dev->bss_list, list) {
277                 if ((bss->pub.capability & capa_mask) != capa_val)
278                         continue;
279                 if (channel && bss->pub.channel != channel)
280                         continue;
281                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
282                         res = bss;
283                         kref_get(&res->ref);
284                         break;
285                 }
286         }
287
288         spin_unlock_bh(&dev->bss_lock);
289         if (!res)
290                 return NULL;
291         return &res->pub;
292 }
293 EXPORT_SYMBOL(cfg80211_get_bss);
294
295 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
296                                        struct ieee80211_channel *channel,
297                                        const u8 *meshid, size_t meshidlen,
298                                        const u8 *meshcfg)
299 {
300         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
301         struct cfg80211_internal_bss *bss, *res = NULL;
302
303         spin_lock_bh(&dev->bss_lock);
304
305         list_for_each_entry(bss, &dev->bss_list, list) {
306                 if (channel && bss->pub.channel != channel)
307                         continue;
308                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
309                         res = bss;
310                         kref_get(&res->ref);
311                         break;
312                 }
313         }
314
315         spin_unlock_bh(&dev->bss_lock);
316         if (!res)
317                 return NULL;
318         return &res->pub;
319 }
320 EXPORT_SYMBOL(cfg80211_get_mesh);
321
322
323 static void rb_insert_bss(struct cfg80211_registered_device *dev,
324                           struct cfg80211_internal_bss *bss)
325 {
326         struct rb_node **p = &dev->bss_tree.rb_node;
327         struct rb_node *parent = NULL;
328         struct cfg80211_internal_bss *tbss;
329         int cmp;
330
331         while (*p) {
332                 parent = *p;
333                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
334
335                 cmp = cmp_bss(&bss->pub, &tbss->pub);
336
337                 if (WARN_ON(!cmp)) {
338                         /* will sort of leak this BSS */
339                         return;
340                 }
341
342                 if (cmp < 0)
343                         p = &(*p)->rb_left;
344                 else
345                         p = &(*p)->rb_right;
346         }
347
348         rb_link_node(&bss->rbn, parent, p);
349         rb_insert_color(&bss->rbn, &dev->bss_tree);
350 }
351
352 static struct cfg80211_internal_bss *
353 rb_find_bss(struct cfg80211_registered_device *dev,
354             struct cfg80211_internal_bss *res)
355 {
356         struct rb_node *n = dev->bss_tree.rb_node;
357         struct cfg80211_internal_bss *bss;
358         int r;
359
360         while (n) {
361                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
362                 r = cmp_bss(&res->pub, &bss->pub);
363
364                 if (r == 0)
365                         return bss;
366                 else if (r < 0)
367                         n = n->rb_left;
368                 else
369                         n = n->rb_right;
370         }
371
372         return NULL;
373 }
374
375 static struct cfg80211_internal_bss *
376 cfg80211_bss_update(struct cfg80211_registered_device *dev,
377                     struct cfg80211_internal_bss *res,
378                     bool overwrite)
379 {
380         struct cfg80211_internal_bss *found = NULL;
381         const u8 *meshid, *meshcfg;
382
383         /*
384          * The reference to "res" is donated to this function.
385          */
386
387         if (WARN_ON(!res->pub.channel)) {
388                 kref_put(&res->ref, bss_release);
389                 return NULL;
390         }
391
392         res->ts = jiffies;
393
394         if (is_zero_ether_addr(res->pub.bssid)) {
395                 /* must be mesh, verify */
396                 meshid = find_ie(WLAN_EID_MESH_ID, res->pub.information_elements,
397                                  res->pub.len_information_elements);
398                 meshcfg = find_ie(WLAN_EID_MESH_CONFIG,
399                                   res->pub.information_elements,
400                                   res->pub.len_information_elements);
401                 if (!meshid || !meshcfg ||
402                     meshcfg[1] != IEEE80211_MESH_CONFIG_LEN) {
403                         /* bogus mesh */
404                         kref_put(&res->ref, bss_release);
405                         return NULL;
406                 }
407         }
408
409         spin_lock_bh(&dev->bss_lock);
410
411         found = rb_find_bss(dev, res);
412
413         if (found) {
414                 found->pub.beacon_interval = res->pub.beacon_interval;
415                 found->pub.tsf = res->pub.tsf;
416                 found->pub.signal = res->pub.signal;
417                 found->pub.capability = res->pub.capability;
418                 found->ts = res->ts;
419
420                 /* overwrite IEs */
421                 if (overwrite) {
422                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
423                         size_t ielen = res->pub.len_information_elements;
424
425                         if (!found->ies_allocated && ksize(found) >= used + ielen) {
426                                 memcpy(found->pub.information_elements,
427                                        res->pub.information_elements, ielen);
428                                 found->pub.len_information_elements = ielen;
429                         } else {
430                                 u8 *ies = found->pub.information_elements;
431
432                                 if (found->ies_allocated)
433                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
434                                 else
435                                         ies = kmalloc(ielen, GFP_ATOMIC);
436
437                                 if (ies) {
438                                         memcpy(ies, res->pub.information_elements, ielen);
439                                         found->ies_allocated = true;
440                                         found->pub.information_elements = ies;
441                                         found->pub.len_information_elements = ielen;
442                                 }
443                         }
444                 }
445
446                 kref_put(&res->ref, bss_release);
447         } else {
448                 /* this "consumes" the reference */
449                 list_add_tail(&res->list, &dev->bss_list);
450                 rb_insert_bss(dev, res);
451                 found = res;
452         }
453
454         dev->bss_generation++;
455         spin_unlock_bh(&dev->bss_lock);
456
457         kref_get(&found->ref);
458         return found;
459 }
460
461 struct cfg80211_bss*
462 cfg80211_inform_bss(struct wiphy *wiphy,
463                     struct ieee80211_channel *channel,
464                     const u8 *bssid,
465                     u64 timestamp, u16 capability, u16 beacon_interval,
466                     const u8 *ie, size_t ielen,
467                     s32 signal, gfp_t gfp)
468 {
469         struct cfg80211_internal_bss *res;
470         size_t privsz;
471
472         if (WARN_ON(!wiphy))
473                 return NULL;
474
475         privsz = wiphy->bss_priv_size;
476
477         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
478                         (signal < 0 || signal > 100)))
479                 return NULL;
480
481         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
482         if (!res)
483                 return NULL;
484
485         memcpy(res->pub.bssid, bssid, ETH_ALEN);
486         res->pub.channel = channel;
487         res->pub.signal = signal;
488         res->pub.tsf = timestamp;
489         res->pub.beacon_interval = beacon_interval;
490         res->pub.capability = capability;
491         /* point to after the private area */
492         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
493         memcpy(res->pub.information_elements, ie, ielen);
494         res->pub.len_information_elements = ielen;
495
496         kref_init(&res->ref);
497
498         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, 0);
499         if (!res)
500                 return NULL;
501
502         if (res->pub.capability & WLAN_CAPABILITY_ESS)
503                 regulatory_hint_found_beacon(wiphy, channel, gfp);
504
505         /* cfg80211_bss_update gives us a referenced result */
506         return &res->pub;
507 }
508 EXPORT_SYMBOL(cfg80211_inform_bss);
509
510 struct cfg80211_bss *
511 cfg80211_inform_bss_frame(struct wiphy *wiphy,
512                           struct ieee80211_channel *channel,
513                           struct ieee80211_mgmt *mgmt, size_t len,
514                           s32 signal, gfp_t gfp)
515 {
516         struct cfg80211_internal_bss *res;
517         size_t ielen = len - offsetof(struct ieee80211_mgmt,
518                                       u.probe_resp.variable);
519         bool overwrite;
520         size_t privsz = wiphy->bss_priv_size;
521
522         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
523                     (signal < 0 || signal > 100)))
524                 return NULL;
525
526         if (WARN_ON(!mgmt || !wiphy ||
527                     len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
528                 return NULL;
529
530         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
531         if (!res)
532                 return NULL;
533
534         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
535         res->pub.channel = channel;
536         res->pub.signal = signal;
537         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
538         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
539         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
540         /* point to after the private area */
541         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
542         memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
543         res->pub.len_information_elements = ielen;
544
545         kref_init(&res->ref);
546
547         overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
548
549         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
550         if (!res)
551                 return NULL;
552
553         if (res->pub.capability & WLAN_CAPABILITY_ESS)
554                 regulatory_hint_found_beacon(wiphy, channel, gfp);
555
556         /* cfg80211_bss_update gives us a referenced result */
557         return &res->pub;
558 }
559 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
560
561 void cfg80211_put_bss(struct cfg80211_bss *pub)
562 {
563         struct cfg80211_internal_bss *bss;
564
565         if (!pub)
566                 return;
567
568         bss = container_of(pub, struct cfg80211_internal_bss, pub);
569         kref_put(&bss->ref, bss_release);
570 }
571 EXPORT_SYMBOL(cfg80211_put_bss);
572
573 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
574 {
575         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
576         struct cfg80211_internal_bss *bss;
577
578         if (WARN_ON(!pub))
579                 return;
580
581         bss = container_of(pub, struct cfg80211_internal_bss, pub);
582
583         spin_lock_bh(&dev->bss_lock);
584
585         list_del(&bss->list);
586         dev->bss_generation++;
587         rb_erase(&bss->rbn, &dev->bss_tree);
588
589         spin_unlock_bh(&dev->bss_lock);
590
591         kref_put(&bss->ref, bss_release);
592 }
593 EXPORT_SYMBOL(cfg80211_unlink_bss);
594
595 #ifdef CONFIG_WIRELESS_EXT
596 int cfg80211_wext_siwscan(struct net_device *dev,
597                           struct iw_request_info *info,
598                           union iwreq_data *wrqu, char *extra)
599 {
600         struct cfg80211_registered_device *rdev;
601         struct wiphy *wiphy;
602         struct iw_scan_req *wreq = NULL;
603         struct cfg80211_scan_request *creq;
604         int i, err, n_channels = 0;
605         enum ieee80211_band band;
606
607         if (!netif_running(dev))
608                 return -ENETDOWN;
609
610         if (wrqu->data.length == sizeof(struct iw_scan_req))
611                 wreq = (struct iw_scan_req *)extra;
612
613         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
614
615         if (IS_ERR(rdev))
616                 return PTR_ERR(rdev);
617
618         if (rdev->scan_req) {
619                 err = -EBUSY;
620                 goto out;
621         }
622
623         wiphy = &rdev->wiphy;
624
625         /* Determine number of channels, needed to allocate creq */
626         if (wreq && wreq->num_channels)
627                 n_channels = wreq->num_channels;
628         else {
629                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
630                         if (wiphy->bands[band])
631                                 n_channels += wiphy->bands[band]->n_channels;
632         }
633
634         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
635                        n_channels * sizeof(void *),
636                        GFP_ATOMIC);
637         if (!creq) {
638                 err = -ENOMEM;
639                 goto out;
640         }
641
642         creq->wiphy = wiphy;
643         creq->dev = dev;
644         /* SSIDs come after channels */
645         creq->ssids = (void *)&creq->channels[n_channels];
646         creq->n_channels = n_channels;
647         creq->n_ssids = 1;
648
649         /* translate "Scan on frequencies" request */
650         i = 0;
651         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
652                 int j;
653                 if (!wiphy->bands[band])
654                         continue;
655                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
656
657                         /* If we have a wireless request structure and the
658                          * wireless request specifies frequencies, then search
659                          * for the matching hardware channel.
660                          */
661                         if (wreq && wreq->num_channels) {
662                                 int k;
663                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
664                                 for (k = 0; k < wreq->num_channels; k++) {
665                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
666                                         if (wext_freq == wiphy_freq)
667                                                 goto wext_freq_found;
668                                 }
669                                 goto wext_freq_not_found;
670                         }
671
672                 wext_freq_found:
673                         creq->channels[i] = &wiphy->bands[band]->channels[j];
674                         i++;
675                 wext_freq_not_found: ;
676                 }
677         }
678         /* No channels found? */
679         if (!i) {
680                 err = -EINVAL;
681                 goto out;
682         }
683
684         /* Set real number of channels specified in creq->channels[] */
685         creq->n_channels = i;
686
687         /* translate "Scan for SSID" request */
688         if (wreq) {
689                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
690                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
691                                 return -EINVAL;
692                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
693                         creq->ssids[0].ssid_len = wreq->essid_len;
694                 }
695                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
696                         creq->n_ssids = 0;
697         }
698
699         rdev->scan_req = creq;
700         err = rdev->ops->scan(wiphy, dev, creq);
701         if (err) {
702                 rdev->scan_req = NULL;
703                 kfree(creq);
704         } else {
705                 nl80211_send_scan_start(rdev, dev);
706                 dev_hold(dev);
707         }
708  out:
709         cfg80211_unlock_rdev(rdev);
710         return err;
711 }
712 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
713
714 static void ieee80211_scan_add_ies(struct iw_request_info *info,
715                                    struct cfg80211_bss *bss,
716                                    char **current_ev, char *end_buf)
717 {
718         u8 *pos, *end, *next;
719         struct iw_event iwe;
720
721         if (!bss->information_elements ||
722             !bss->len_information_elements)
723                 return;
724
725         /*
726          * If needed, fragment the IEs buffer (at IE boundaries) into short
727          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
728          */
729         pos = bss->information_elements;
730         end = pos + bss->len_information_elements;
731
732         while (end - pos > IW_GENERIC_IE_MAX) {
733                 next = pos + 2 + pos[1];
734                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
735                         next = next + 2 + next[1];
736
737                 memset(&iwe, 0, sizeof(iwe));
738                 iwe.cmd = IWEVGENIE;
739                 iwe.u.data.length = next - pos;
740                 *current_ev = iwe_stream_add_point(info, *current_ev,
741                                                    end_buf, &iwe, pos);
742
743                 pos = next;
744         }
745
746         if (end > pos) {
747                 memset(&iwe, 0, sizeof(iwe));
748                 iwe.cmd = IWEVGENIE;
749                 iwe.u.data.length = end - pos;
750                 *current_ev = iwe_stream_add_point(info, *current_ev,
751                                                    end_buf, &iwe, pos);
752         }
753 }
754
755 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
756 {
757         unsigned long end = jiffies;
758
759         if (end >= start)
760                 return jiffies_to_msecs(end - start);
761
762         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
763 }
764
765 static char *
766 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
767               struct cfg80211_internal_bss *bss, char *current_ev,
768               char *end_buf)
769 {
770         struct iw_event iwe;
771         u8 *buf, *cfg, *p;
772         u8 *ie = bss->pub.information_elements;
773         int rem = bss->pub.len_information_elements, i, sig;
774         bool ismesh = false;
775
776         memset(&iwe, 0, sizeof(iwe));
777         iwe.cmd = SIOCGIWAP;
778         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
779         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
780         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
781                                           IW_EV_ADDR_LEN);
782
783         memset(&iwe, 0, sizeof(iwe));
784         iwe.cmd = SIOCGIWFREQ;
785         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
786         iwe.u.freq.e = 0;
787         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
788                                           IW_EV_FREQ_LEN);
789
790         memset(&iwe, 0, sizeof(iwe));
791         iwe.cmd = SIOCGIWFREQ;
792         iwe.u.freq.m = bss->pub.channel->center_freq;
793         iwe.u.freq.e = 6;
794         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
795                                           IW_EV_FREQ_LEN);
796
797         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
798                 memset(&iwe, 0, sizeof(iwe));
799                 iwe.cmd = IWEVQUAL;
800                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
801                                      IW_QUAL_NOISE_INVALID |
802                                      IW_QUAL_QUAL_UPDATED;
803                 switch (wiphy->signal_type) {
804                 case CFG80211_SIGNAL_TYPE_MBM:
805                         sig = bss->pub.signal / 100;
806                         iwe.u.qual.level = sig;
807                         iwe.u.qual.updated |= IW_QUAL_DBM;
808                         if (sig < -110)         /* rather bad */
809                                 sig = -110;
810                         else if (sig > -40)     /* perfect */
811                                 sig = -40;
812                         /* will give a range of 0 .. 70 */
813                         iwe.u.qual.qual = sig + 110;
814                         break;
815                 case CFG80211_SIGNAL_TYPE_UNSPEC:
816                         iwe.u.qual.level = bss->pub.signal;
817                         /* will give range 0 .. 100 */
818                         iwe.u.qual.qual = bss->pub.signal;
819                         break;
820                 default:
821                         /* not reached */
822                         break;
823                 }
824                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
825                                                   &iwe, IW_EV_QUAL_LEN);
826         }
827
828         memset(&iwe, 0, sizeof(iwe));
829         iwe.cmd = SIOCGIWENCODE;
830         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
831                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
832         else
833                 iwe.u.data.flags = IW_ENCODE_DISABLED;
834         iwe.u.data.length = 0;
835         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
836                                           &iwe, "");
837
838         while (rem >= 2) {
839                 /* invalid data */
840                 if (ie[1] > rem - 2)
841                         break;
842
843                 switch (ie[0]) {
844                 case WLAN_EID_SSID:
845                         memset(&iwe, 0, sizeof(iwe));
846                         iwe.cmd = SIOCGIWESSID;
847                         iwe.u.data.length = ie[1];
848                         iwe.u.data.flags = 1;
849                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
850                                                           &iwe, ie + 2);
851                         break;
852                 case WLAN_EID_MESH_ID:
853                         memset(&iwe, 0, sizeof(iwe));
854                         iwe.cmd = SIOCGIWESSID;
855                         iwe.u.data.length = ie[1];
856                         iwe.u.data.flags = 1;
857                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
858                                                           &iwe, ie + 2);
859                         break;
860                 case WLAN_EID_MESH_CONFIG:
861                         ismesh = true;
862                         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
863                                 break;
864                         buf = kmalloc(50, GFP_ATOMIC);
865                         if (!buf)
866                                 break;
867                         cfg = ie + 2;
868                         memset(&iwe, 0, sizeof(iwe));
869                         iwe.cmd = IWEVCUSTOM;
870                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
871                         iwe.u.data.length = strlen(buf);
872                         current_ev = iwe_stream_add_point(info, current_ev,
873                                                           end_buf,
874                                                           &iwe, buf);
875                         sprintf(buf, "Path Selection Protocol ID: "
876                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
877                                                         cfg[4]);
878                         iwe.u.data.length = strlen(buf);
879                         current_ev = iwe_stream_add_point(info, current_ev,
880                                                           end_buf,
881                                                           &iwe, buf);
882                         sprintf(buf, "Path Selection Metric ID: "
883                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
884                                                         cfg[8]);
885                         iwe.u.data.length = strlen(buf);
886                         current_ev = iwe_stream_add_point(info, current_ev,
887                                                           end_buf,
888                                                           &iwe, buf);
889                         sprintf(buf, "Congestion Control Mode ID: "
890                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
891                                                         cfg[11], cfg[12]);
892                         iwe.u.data.length = strlen(buf);
893                         current_ev = iwe_stream_add_point(info, current_ev,
894                                                           end_buf,
895                                                           &iwe, buf);
896                         sprintf(buf, "Channel Precedence: "
897                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
898                                                         cfg[15], cfg[16]);
899                         iwe.u.data.length = strlen(buf);
900                         current_ev = iwe_stream_add_point(info, current_ev,
901                                                           end_buf,
902                                                           &iwe, buf);
903                         kfree(buf);
904                         break;
905                 case WLAN_EID_SUPP_RATES:
906                 case WLAN_EID_EXT_SUPP_RATES:
907                         /* display all supported rates in readable format */
908                         p = current_ev + iwe_stream_lcp_len(info);
909
910                         memset(&iwe, 0, sizeof(iwe));
911                         iwe.cmd = SIOCGIWRATE;
912                         /* Those two flags are ignored... */
913                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
914
915                         for (i = 0; i < ie[1]; i++) {
916                                 iwe.u.bitrate.value =
917                                         ((ie[i + 2] & 0x7f) * 500000);
918                                 p = iwe_stream_add_value(info, current_ev, p,
919                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
920                         }
921                         current_ev = p;
922                         break;
923                 }
924                 rem -= ie[1] + 2;
925                 ie += ie[1] + 2;
926         }
927
928         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
929             || ismesh) {
930                 memset(&iwe, 0, sizeof(iwe));
931                 iwe.cmd = SIOCGIWMODE;
932                 if (ismesh)
933                         iwe.u.mode = IW_MODE_MESH;
934                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
935                         iwe.u.mode = IW_MODE_MASTER;
936                 else
937                         iwe.u.mode = IW_MODE_ADHOC;
938                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
939                                                   &iwe, IW_EV_UINT_LEN);
940         }
941
942         buf = kmalloc(30, GFP_ATOMIC);
943         if (buf) {
944                 memset(&iwe, 0, sizeof(iwe));
945                 iwe.cmd = IWEVCUSTOM;
946                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
947                 iwe.u.data.length = strlen(buf);
948                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
949                                                   &iwe, buf);
950                 memset(&iwe, 0, sizeof(iwe));
951                 iwe.cmd = IWEVCUSTOM;
952                 sprintf(buf, " Last beacon: %ums ago",
953                         elapsed_jiffies_msecs(bss->ts));
954                 iwe.u.data.length = strlen(buf);
955                 current_ev = iwe_stream_add_point(info, current_ev,
956                                                   end_buf, &iwe, buf);
957                 kfree(buf);
958         }
959
960         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
961
962         return current_ev;
963 }
964
965
966 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
967                                   struct iw_request_info *info,
968                                   char *buf, size_t len)
969 {
970         char *current_ev = buf;
971         char *end_buf = buf + len;
972         struct cfg80211_internal_bss *bss;
973
974         spin_lock_bh(&dev->bss_lock);
975         cfg80211_bss_expire(dev);
976
977         list_for_each_entry(bss, &dev->bss_list, list) {
978                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
979                         spin_unlock_bh(&dev->bss_lock);
980                         return -E2BIG;
981                 }
982                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
983                                            current_ev, end_buf);
984         }
985         spin_unlock_bh(&dev->bss_lock);
986         return current_ev - buf;
987 }
988
989
990 int cfg80211_wext_giwscan(struct net_device *dev,
991                           struct iw_request_info *info,
992                           struct iw_point *data, char *extra)
993 {
994         struct cfg80211_registered_device *rdev;
995         int res;
996
997         if (!netif_running(dev))
998                 return -ENETDOWN;
999
1000         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1001
1002         if (IS_ERR(rdev))
1003                 return PTR_ERR(rdev);
1004
1005         if (rdev->scan_req) {
1006                 res = -EAGAIN;
1007                 goto out;
1008         }
1009
1010         res = ieee80211_scan_results(rdev, info, extra, data->length);
1011         data->length = 0;
1012         if (res >= 0) {
1013                 data->length = res;
1014                 res = 0;
1015         }
1016
1017  out:
1018         cfg80211_unlock_rdev(rdev);
1019         return res;
1020 }
1021 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1022 #endif