mac80211: fix beacon enable more
[safe/jmp/linux-2.6] / net / mac80211 / scan.c
1 /*
2  * Scanning implementation
3  *
4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5  * Copyright 2004, Instant802 Networks, Inc.
6  * Copyright 2005, Devicescape Software, Inc.
7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14
15 /* TODO:
16  * order BSS list by RSSI(?) ("quality of AP")
17  * scan result table filtering (by capability (privacy, IBSS/BSS, WPA/RSN IE,
18  *    SSID)
19  */
20
21 #include <linux/wireless.h>
22 #include <linux/if_arp.h>
23 #include <linux/rtnetlink.h>
24 #include <net/mac80211.h>
25 #include <net/iw_handler.h>
26
27 #include "ieee80211_i.h"
28 #include "mesh.h"
29
30 #define IEEE80211_PROBE_DELAY (HZ / 33)
31 #define IEEE80211_CHANNEL_TIME (HZ / 33)
32 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
33
34 void ieee80211_rx_bss_list_init(struct ieee80211_local *local)
35 {
36         spin_lock_init(&local->bss_lock);
37         INIT_LIST_HEAD(&local->bss_list);
38 }
39
40 void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local)
41 {
42         struct ieee80211_bss *bss, *tmp;
43
44         list_for_each_entry_safe(bss, tmp, &local->bss_list, list)
45                 ieee80211_rx_bss_put(local, bss);
46 }
47
48 struct ieee80211_bss *
49 ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
50                      u8 *ssid, u8 ssid_len)
51 {
52         struct ieee80211_bss *bss;
53
54         spin_lock_bh(&local->bss_lock);
55         bss = local->bss_hash[STA_HASH(bssid)];
56         while (bss) {
57                 if (!bss_mesh_cfg(bss) &&
58                     !memcmp(bss->bssid, bssid, ETH_ALEN) &&
59                     bss->freq == freq &&
60                     bss->ssid_len == ssid_len &&
61                     (ssid_len == 0 || !memcmp(bss->ssid, ssid, ssid_len))) {
62                         atomic_inc(&bss->users);
63                         break;
64                 }
65                 bss = bss->hnext;
66         }
67         spin_unlock_bh(&local->bss_lock);
68         return bss;
69 }
70
71 /* Caller must hold local->bss_lock */
72 static void __ieee80211_rx_bss_hash_add(struct ieee80211_local *local,
73                                         struct ieee80211_bss *bss)
74 {
75         u8 hash_idx;
76
77         if (bss_mesh_cfg(bss))
78                 hash_idx = mesh_id_hash(bss_mesh_id(bss),
79                                         bss_mesh_id_len(bss));
80         else
81                 hash_idx = STA_HASH(bss->bssid);
82
83         bss->hnext = local->bss_hash[hash_idx];
84         local->bss_hash[hash_idx] = bss;
85 }
86
87 /* Caller must hold local->bss_lock */
88 static void __ieee80211_rx_bss_hash_del(struct ieee80211_local *local,
89                                         struct ieee80211_bss *bss)
90 {
91         struct ieee80211_bss *b, *prev = NULL;
92         b = local->bss_hash[STA_HASH(bss->bssid)];
93         while (b) {
94                 if (b == bss) {
95                         if (!prev)
96                                 local->bss_hash[STA_HASH(bss->bssid)] =
97                                         bss->hnext;
98                         else
99                                 prev->hnext = bss->hnext;
100                         break;
101                 }
102                 prev = b;
103                 b = b->hnext;
104         }
105 }
106
107 struct ieee80211_bss *
108 ieee80211_rx_bss_add(struct ieee80211_local *local, u8 *bssid, int freq,
109                      u8 *ssid, u8 ssid_len)
110 {
111         struct ieee80211_bss *bss;
112
113         bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
114         if (!bss)
115                 return NULL;
116         atomic_set(&bss->users, 2);
117         memcpy(bss->bssid, bssid, ETH_ALEN);
118         bss->freq = freq;
119         if (ssid && ssid_len <= IEEE80211_MAX_SSID_LEN) {
120                 memcpy(bss->ssid, ssid, ssid_len);
121                 bss->ssid_len = ssid_len;
122         }
123
124         spin_lock_bh(&local->bss_lock);
125         /* TODO: order by RSSI? */
126         list_add_tail(&bss->list, &local->bss_list);
127         __ieee80211_rx_bss_hash_add(local, bss);
128         spin_unlock_bh(&local->bss_lock);
129         return bss;
130 }
131
132 #ifdef CONFIG_MAC80211_MESH
133 static struct ieee80211_bss *
134 ieee80211_rx_mesh_bss_get(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
135                           u8 *mesh_cfg, int freq)
136 {
137         struct ieee80211_bss *bss;
138
139         spin_lock_bh(&local->bss_lock);
140         bss = local->bss_hash[mesh_id_hash(mesh_id, mesh_id_len)];
141         while (bss) {
142                 if (bss_mesh_cfg(bss) &&
143                     !memcmp(bss_mesh_cfg(bss), mesh_cfg, MESH_CFG_CMP_LEN) &&
144                     bss->freq == freq &&
145                     mesh_id_len == bss->mesh_id_len &&
146                     (mesh_id_len == 0 || !memcmp(bss->mesh_id, mesh_id,
147                                                  mesh_id_len))) {
148                         atomic_inc(&bss->users);
149                         break;
150                 }
151                 bss = bss->hnext;
152         }
153         spin_unlock_bh(&local->bss_lock);
154         return bss;
155 }
156
157 static struct ieee80211_bss *
158 ieee80211_rx_mesh_bss_add(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
159                           u8 *mesh_cfg, int mesh_config_len, int freq)
160 {
161         struct ieee80211_bss *bss;
162
163         if (mesh_config_len != IEEE80211_MESH_CONFIG_LEN)
164                 return NULL;
165
166         bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
167         if (!bss)
168                 return NULL;
169
170         bss->mesh_cfg = kmalloc(MESH_CFG_CMP_LEN, GFP_ATOMIC);
171         if (!bss->mesh_cfg) {
172                 kfree(bss);
173                 return NULL;
174         }
175
176         if (mesh_id_len && mesh_id_len <= IEEE80211_MAX_MESH_ID_LEN) {
177                 bss->mesh_id = kmalloc(mesh_id_len, GFP_ATOMIC);
178                 if (!bss->mesh_id) {
179                         kfree(bss->mesh_cfg);
180                         kfree(bss);
181                         return NULL;
182                 }
183                 memcpy(bss->mesh_id, mesh_id, mesh_id_len);
184         }
185
186         atomic_set(&bss->users, 2);
187         memcpy(bss->mesh_cfg, mesh_cfg, MESH_CFG_CMP_LEN);
188         bss->mesh_id_len = mesh_id_len;
189         bss->freq = freq;
190         spin_lock_bh(&local->bss_lock);
191         /* TODO: order by RSSI? */
192         list_add_tail(&bss->list, &local->bss_list);
193         __ieee80211_rx_bss_hash_add(local, bss);
194         spin_unlock_bh(&local->bss_lock);
195         return bss;
196 }
197 #endif
198
199 static void ieee80211_rx_bss_free(struct ieee80211_bss *bss)
200 {
201         kfree(bss->ies);
202         kfree(bss_mesh_id(bss));
203         kfree(bss_mesh_cfg(bss));
204         kfree(bss);
205 }
206
207 void ieee80211_rx_bss_put(struct ieee80211_local *local,
208                           struct ieee80211_bss *bss)
209 {
210         local_bh_disable();
211         if (!atomic_dec_and_lock(&bss->users, &local->bss_lock)) {
212                 local_bh_enable();
213                 return;
214         }
215
216         __ieee80211_rx_bss_hash_del(local, bss);
217         list_del(&bss->list);
218         spin_unlock_bh(&local->bss_lock);
219         ieee80211_rx_bss_free(bss);
220 }
221
222 struct ieee80211_bss *
223 ieee80211_bss_info_update(struct ieee80211_local *local,
224                           struct ieee80211_rx_status *rx_status,
225                           struct ieee80211_mgmt *mgmt,
226                           size_t len,
227                           struct ieee802_11_elems *elems,
228                           int freq, bool beacon)
229 {
230         struct ieee80211_bss *bss;
231         int clen;
232
233 #ifdef CONFIG_MAC80211_MESH
234         if (elems->mesh_config)
235                 bss = ieee80211_rx_mesh_bss_get(local, elems->mesh_id,
236                                 elems->mesh_id_len, elems->mesh_config, freq);
237         else
238 #endif
239                 bss = ieee80211_rx_bss_get(local, mgmt->bssid, freq,
240                                            elems->ssid, elems->ssid_len);
241         if (!bss) {
242 #ifdef CONFIG_MAC80211_MESH
243                 if (elems->mesh_config)
244                         bss = ieee80211_rx_mesh_bss_add(local, elems->mesh_id,
245                                 elems->mesh_id_len, elems->mesh_config,
246                                 elems->mesh_config_len, freq);
247                 else
248 #endif
249                         bss = ieee80211_rx_bss_add(local, mgmt->bssid, freq,
250                                                   elems->ssid, elems->ssid_len);
251                 if (!bss)
252                         return NULL;
253         } else {
254 #if 0
255                 /* TODO: order by RSSI? */
256                 spin_lock_bh(&local->bss_lock);
257                 list_move_tail(&bss->list, &local->bss_list);
258                 spin_unlock_bh(&local->bss_lock);
259 #endif
260         }
261
262         /* save the ERP value so that it is available at association time */
263         if (elems->erp_info && elems->erp_info_len >= 1) {
264                 bss->erp_value = elems->erp_info[0];
265                 bss->has_erp_value = 1;
266         }
267
268         bss->beacon_int = le16_to_cpu(mgmt->u.beacon.beacon_int);
269         bss->capability = le16_to_cpu(mgmt->u.beacon.capab_info);
270
271         if (elems->tim) {
272                 struct ieee80211_tim_ie *tim_ie =
273                         (struct ieee80211_tim_ie *)elems->tim;
274                 bss->dtim_period = tim_ie->dtim_period;
275         }
276
277         /* set default value for buggy APs */
278         if (!elems->tim || bss->dtim_period == 0)
279                 bss->dtim_period = 1;
280
281         bss->supp_rates_len = 0;
282         if (elems->supp_rates) {
283                 clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
284                 if (clen > elems->supp_rates_len)
285                         clen = elems->supp_rates_len;
286                 memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates,
287                        clen);
288                 bss->supp_rates_len += clen;
289         }
290         if (elems->ext_supp_rates) {
291                 clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
292                 if (clen > elems->ext_supp_rates_len)
293                         clen = elems->ext_supp_rates_len;
294                 memcpy(&bss->supp_rates[bss->supp_rates_len],
295                        elems->ext_supp_rates, clen);
296                 bss->supp_rates_len += clen;
297         }
298
299         bss->band = rx_status->band;
300
301         bss->timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
302         bss->last_update = jiffies;
303         bss->signal = rx_status->signal;
304         bss->noise = rx_status->noise;
305         bss->qual = rx_status->qual;
306         bss->wmm_used = elems->wmm_param || elems->wmm_info;
307
308         if (!beacon)
309                 bss->last_probe_resp = jiffies;
310
311         /*
312          * For probe responses, or if we don't have any information yet,
313          * use the IEs from the beacon.
314          */
315         if (!bss->ies || !beacon) {
316                 if (bss->ies == NULL || bss->ies_len < elems->total_len) {
317                         kfree(bss->ies);
318                         bss->ies = kmalloc(elems->total_len, GFP_ATOMIC);
319                 }
320                 if (bss->ies) {
321                         memcpy(bss->ies, elems->ie_start, elems->total_len);
322                         bss->ies_len = elems->total_len;
323                 } else
324                         bss->ies_len = 0;
325         }
326
327         return bss;
328 }
329
330 void ieee80211_rx_bss_remove(struct ieee80211_sub_if_data *sdata, u8 *bssid,
331                              int freq, u8 *ssid, u8 ssid_len)
332 {
333         struct ieee80211_bss *bss;
334         struct ieee80211_local *local = sdata->local;
335
336         bss = ieee80211_rx_bss_get(local, bssid, freq, ssid, ssid_len);
337         if (bss) {
338                 atomic_dec(&bss->users);
339                 ieee80211_rx_bss_put(local, bss);
340         }
341 }
342
343 ieee80211_rx_result
344 ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
345                   struct ieee80211_rx_status *rx_status)
346 {
347         struct ieee80211_mgmt *mgmt;
348         struct ieee80211_bss *bss;
349         u8 *elements;
350         struct ieee80211_channel *channel;
351         size_t baselen;
352         int freq;
353         __le16 fc;
354         bool presp, beacon = false;
355         struct ieee802_11_elems elems;
356
357         if (skb->len < 2)
358                 return RX_DROP_UNUSABLE;
359
360         mgmt = (struct ieee80211_mgmt *) skb->data;
361         fc = mgmt->frame_control;
362
363         if (ieee80211_is_ctl(fc))
364                 return RX_CONTINUE;
365
366         if (skb->len < 24)
367                 return RX_DROP_MONITOR;
368
369         presp = ieee80211_is_probe_resp(fc);
370         if (presp) {
371                 /* ignore ProbeResp to foreign address */
372                 if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
373                         return RX_DROP_MONITOR;
374
375                 presp = true;
376                 elements = mgmt->u.probe_resp.variable;
377                 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
378         } else {
379                 beacon = ieee80211_is_beacon(fc);
380                 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
381                 elements = mgmt->u.beacon.variable;
382         }
383
384         if (!presp && !beacon)
385                 return RX_CONTINUE;
386
387         if (baselen > skb->len)
388                 return RX_DROP_MONITOR;
389
390         ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
391
392         if (elems.ds_params && elems.ds_params_len == 1)
393                 freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
394         else
395                 freq = rx_status->freq;
396
397         channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
398
399         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
400                 return RX_DROP_MONITOR;
401
402         bss = ieee80211_bss_info_update(sdata->local, rx_status,
403                                         mgmt, skb->len, &elems,
404                                         freq, beacon);
405         if (bss)
406                 ieee80211_rx_bss_put(sdata->local, bss);
407
408         dev_kfree_skb(skb);
409         return RX_QUEUED;
410 }
411
412 void ieee80211_send_nullfunc(struct ieee80211_local *local,
413                                     struct ieee80211_sub_if_data *sdata,
414                                     int powersave)
415 {
416         struct sk_buff *skb;
417         struct ieee80211_hdr *nullfunc;
418         __le16 fc;
419
420         skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
421         if (!skb) {
422                 printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
423                        "frame\n", sdata->dev->name);
424                 return;
425         }
426         skb_reserve(skb, local->hw.extra_tx_headroom);
427
428         nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
429         memset(nullfunc, 0, 24);
430         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
431                          IEEE80211_FCTL_TODS);
432         if (powersave)
433                 fc |= cpu_to_le16(IEEE80211_FCTL_PM);
434         nullfunc->frame_control = fc;
435         memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
436         memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
437         memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
438
439         ieee80211_tx_skb(sdata, skb, 0);
440 }
441
442 void ieee80211_scan_completed(struct ieee80211_hw *hw)
443 {
444         struct ieee80211_local *local = hw_to_local(hw);
445         struct ieee80211_sub_if_data *sdata;
446         union iwreq_data wrqu;
447
448         if (WARN_ON(!local->hw_scanning && !local->sw_scanning))
449                 return;
450
451         local->last_scan_completed = jiffies;
452         memset(&wrqu, 0, sizeof(wrqu));
453
454         /*
455          * local->scan_sdata could have been NULLed by the interface
456          * down code in case we were scanning on an interface that is
457          * being taken down.
458          */
459         sdata = local->scan_sdata;
460         if (sdata)
461                 wireless_send_event(sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
462
463         if (local->hw_scanning) {
464                 local->hw_scanning = false;
465                 /*
466                  * Somebody might have requested channel change during scan
467                  * that we won't have acted upon, try now. ieee80211_hw_config
468                  * will set the flag based on actual changes.
469                  */
470                 ieee80211_hw_config(local, 0);
471                 goto done;
472         }
473
474         local->sw_scanning = false;
475         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
476
477         netif_tx_lock_bh(local->mdev);
478         netif_addr_lock(local->mdev);
479         local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
480         local->ops->configure_filter(local_to_hw(local),
481                                      FIF_BCN_PRBRESP_PROMISC,
482                                      &local->filter_flags,
483                                      local->mdev->mc_count,
484                                      local->mdev->mc_list);
485
486         netif_addr_unlock(local->mdev);
487         netif_tx_unlock_bh(local->mdev);
488
489         mutex_lock(&local->iflist_mtx);
490         list_for_each_entry(sdata, &local->interfaces, list) {
491                 if (!netif_running(sdata->dev))
492                         continue;
493
494                 /* Tell AP we're back */
495                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
496                         if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
497                                 ieee80211_send_nullfunc(local, sdata, 0);
498                                 netif_tx_wake_all_queues(sdata->dev);
499                         }
500                 } else
501                         netif_tx_wake_all_queues(sdata->dev);
502
503                 /* re-enable beaconing */
504                 if (sdata->vif.type == NL80211_IFTYPE_AP ||
505                     sdata->vif.type == NL80211_IFTYPE_ADHOC ||
506                     sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
507                         ieee80211_if_config(sdata,
508                                             IEEE80211_IFCC_BEACON_ENABLED);
509         }
510         mutex_unlock(&local->iflist_mtx);
511
512  done:
513         ieee80211_mlme_notify_scan_completed(local);
514         ieee80211_mesh_notify_scan_completed(local);
515 }
516 EXPORT_SYMBOL(ieee80211_scan_completed);
517
518 void ieee80211_scan_work(struct work_struct *work)
519 {
520         struct ieee80211_local *local =
521                 container_of(work, struct ieee80211_local, scan_work.work);
522         struct ieee80211_sub_if_data *sdata = local->scan_sdata;
523         struct ieee80211_supported_band *sband;
524         struct ieee80211_channel *chan;
525         int skip;
526         unsigned long next_delay = 0;
527
528         /*
529          * Avoid re-scheduling when the sdata is going away.
530          */
531         if (!netif_running(sdata->dev))
532                 return;
533
534         switch (local->scan_state) {
535         case SCAN_SET_CHANNEL:
536                 /*
537                  * Get current scan band. scan_band may be IEEE80211_NUM_BANDS
538                  * after we successfully scanned the last channel of the last
539                  * band (and the last band is supported by the hw)
540                  */
541                 if (local->scan_band < IEEE80211_NUM_BANDS)
542                         sband = local->hw.wiphy->bands[local->scan_band];
543                 else
544                         sband = NULL;
545
546                 /*
547                  * If we are at an unsupported band and have more bands
548                  * left to scan, advance to the next supported one.
549                  */
550                 while (!sband && local->scan_band < IEEE80211_NUM_BANDS - 1) {
551                         local->scan_band++;
552                         sband = local->hw.wiphy->bands[local->scan_band];
553                         local->scan_channel_idx = 0;
554                 }
555
556                 /* if no more bands/channels left, complete scan */
557                 if (!sband || local->scan_channel_idx >= sband->n_channels) {
558                         ieee80211_scan_completed(local_to_hw(local));
559                         return;
560                 }
561                 skip = 0;
562                 chan = &sband->channels[local->scan_channel_idx];
563
564                 if (chan->flags & IEEE80211_CHAN_DISABLED ||
565                     (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
566                      chan->flags & IEEE80211_CHAN_NO_IBSS))
567                         skip = 1;
568
569                 if (!skip) {
570                         local->scan_channel = chan;
571                         if (ieee80211_hw_config(local,
572                                                 IEEE80211_CONF_CHANGE_CHANNEL))
573                                 skip = 1;
574                 }
575
576                 /* advance state machine to next channel/band */
577                 local->scan_channel_idx++;
578                 if (local->scan_channel_idx >= sband->n_channels) {
579                         /*
580                          * scan_band may end up == IEEE80211_NUM_BANDS, but
581                          * we'll catch that case above and complete the scan
582                          * if that is the case.
583                          */
584                         local->scan_band++;
585                         local->scan_channel_idx = 0;
586                 }
587
588                 if (skip)
589                         break;
590
591                 next_delay = IEEE80211_PROBE_DELAY +
592                              usecs_to_jiffies(local->hw.channel_change_time);
593                 local->scan_state = SCAN_SEND_PROBE;
594                 break;
595         case SCAN_SEND_PROBE:
596                 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
597                 local->scan_state = SCAN_SET_CHANNEL;
598
599                 if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN)
600                         break;
601                 ieee80211_send_probe_req(sdata, NULL, local->scan_ssid,
602                                          local->scan_ssid_len);
603                 next_delay = IEEE80211_CHANNEL_TIME;
604                 break;
605         }
606
607         queue_delayed_work(local->hw.workqueue, &local->scan_work,
608                            next_delay);
609 }
610
611
612 int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata,
613                          u8 *ssid, size_t ssid_len)
614 {
615         struct ieee80211_local *local = scan_sdata->local;
616         struct ieee80211_sub_if_data *sdata;
617
618         if (ssid_len > IEEE80211_MAX_SSID_LEN)
619                 return -EINVAL;
620
621         /* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
622          * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
623          * BSSID: MACAddress
624          * SSID
625          * ScanType: ACTIVE, PASSIVE
626          * ProbeDelay: delay (in microseconds) to be used prior to transmitting
627          *    a Probe frame during active scanning
628          * ChannelList
629          * MinChannelTime (>= ProbeDelay), in TU
630          * MaxChannelTime: (>= MinChannelTime), in TU
631          */
632
633          /* MLME-SCAN.confirm
634           * BSSDescriptionSet
635           * ResultCode: SUCCESS, INVALID_PARAMETERS
636          */
637
638         if (local->sw_scanning || local->hw_scanning) {
639                 if (local->scan_sdata == scan_sdata)
640                         return 0;
641                 return -EBUSY;
642         }
643
644         if (local->ops->hw_scan) {
645                 int rc;
646
647                 local->hw_scanning = true;
648                 rc = local->ops->hw_scan(local_to_hw(local), ssid, ssid_len);
649                 if (rc) {
650                         local->hw_scanning = false;
651                         return rc;
652                 }
653                 local->scan_sdata = scan_sdata;
654                 return 0;
655         }
656
657         local->sw_scanning = true;
658
659         mutex_lock(&local->iflist_mtx);
660         list_for_each_entry(sdata, &local->interfaces, list) {
661                 if (!netif_running(sdata->dev))
662                         continue;
663
664                 /* disable beaconing */
665                 if (sdata->vif.type == NL80211_IFTYPE_AP ||
666                     sdata->vif.type == NL80211_IFTYPE_ADHOC ||
667                     sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
668                         ieee80211_if_config(sdata,
669                                             IEEE80211_IFCC_BEACON_ENABLED);
670
671                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
672                         if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
673                                 netif_tx_stop_all_queues(sdata->dev);
674                                 ieee80211_send_nullfunc(local, sdata, 1);
675                         }
676                 } else
677                         netif_tx_stop_all_queues(sdata->dev);
678         }
679         mutex_unlock(&local->iflist_mtx);
680
681         if (ssid) {
682                 local->scan_ssid_len = ssid_len;
683                 memcpy(local->scan_ssid, ssid, ssid_len);
684         } else
685                 local->scan_ssid_len = 0;
686         local->scan_state = SCAN_SET_CHANNEL;
687         local->scan_channel_idx = 0;
688         local->scan_band = IEEE80211_BAND_2GHZ;
689         local->scan_sdata = scan_sdata;
690
691         netif_addr_lock_bh(local->mdev);
692         local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
693         local->ops->configure_filter(local_to_hw(local),
694                                      FIF_BCN_PRBRESP_PROMISC,
695                                      &local->filter_flags,
696                                      local->mdev->mc_count,
697                                      local->mdev->mc_list);
698         netif_addr_unlock_bh(local->mdev);
699
700         /* TODO: start scan as soon as all nullfunc frames are ACKed */
701         queue_delayed_work(local->hw.workqueue, &local->scan_work,
702                            IEEE80211_CHANNEL_TIME);
703
704         return 0;
705 }
706
707
708 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
709                            u8 *ssid, size_t ssid_len)
710 {
711         struct ieee80211_local *local = sdata->local;
712         struct ieee80211_if_sta *ifsta;
713
714         if (sdata->vif.type != NL80211_IFTYPE_STATION)
715                 return ieee80211_start_scan(sdata, ssid, ssid_len);
716
717         /*
718          * STA has a state machine that might need to defer scanning
719          * while it's trying to associate/authenticate, therefore we
720          * queue it up to the state machine in that case.
721          */
722
723         if (local->sw_scanning || local->hw_scanning) {
724                 if (local->scan_sdata == sdata)
725                         return 0;
726                 return -EBUSY;
727         }
728
729         ifsta = &sdata->u.sta;
730
731         ifsta->scan_ssid_len = ssid_len;
732         if (ssid_len)
733                 memcpy(ifsta->scan_ssid, ssid, ssid_len);
734         set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
735         queue_work(local->hw.workqueue, &ifsta->work);
736
737         return 0;
738 }
739
740
741 static void ieee80211_scan_add_ies(struct iw_request_info *info,
742                                    struct ieee80211_bss *bss,
743                                    char **current_ev, char *end_buf)
744 {
745         u8 *pos, *end, *next;
746         struct iw_event iwe;
747
748         if (bss == NULL || bss->ies == NULL)
749                 return;
750
751         /*
752          * If needed, fragment the IEs buffer (at IE boundaries) into short
753          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
754          */
755         pos = bss->ies;
756         end = pos + bss->ies_len;
757
758         while (end - pos > IW_GENERIC_IE_MAX) {
759                 next = pos + 2 + pos[1];
760                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
761                         next = next + 2 + next[1];
762
763                 memset(&iwe, 0, sizeof(iwe));
764                 iwe.cmd = IWEVGENIE;
765                 iwe.u.data.length = next - pos;
766                 *current_ev = iwe_stream_add_point(info, *current_ev,
767                                                    end_buf, &iwe, pos);
768
769                 pos = next;
770         }
771
772         if (end > pos) {
773                 memset(&iwe, 0, sizeof(iwe));
774                 iwe.cmd = IWEVGENIE;
775                 iwe.u.data.length = end - pos;
776                 *current_ev = iwe_stream_add_point(info, *current_ev,
777                                                    end_buf, &iwe, pos);
778         }
779 }
780
781
782 static char *
783 ieee80211_scan_result(struct ieee80211_local *local,
784                       struct iw_request_info *info,
785                       struct ieee80211_bss *bss,
786                       char *current_ev, char *end_buf)
787 {
788         struct iw_event iwe;
789         char *buf;
790
791         if (time_after(jiffies,
792                        bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE))
793                 return current_ev;
794
795         memset(&iwe, 0, sizeof(iwe));
796         iwe.cmd = SIOCGIWAP;
797         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
798         memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN);
799         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
800                                           IW_EV_ADDR_LEN);
801
802         memset(&iwe, 0, sizeof(iwe));
803         iwe.cmd = SIOCGIWESSID;
804         if (bss_mesh_cfg(bss)) {
805                 iwe.u.data.length = bss_mesh_id_len(bss);
806                 iwe.u.data.flags = 1;
807                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
808                                                   &iwe, bss_mesh_id(bss));
809         } else {
810                 iwe.u.data.length = bss->ssid_len;
811                 iwe.u.data.flags = 1;
812                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
813                                                   &iwe, bss->ssid);
814         }
815
816         if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
817             || bss_mesh_cfg(bss)) {
818                 memset(&iwe, 0, sizeof(iwe));
819                 iwe.cmd = SIOCGIWMODE;
820                 if (bss_mesh_cfg(bss))
821                         iwe.u.mode = IW_MODE_MESH;
822                 else if (bss->capability & WLAN_CAPABILITY_ESS)
823                         iwe.u.mode = IW_MODE_MASTER;
824                 else
825                         iwe.u.mode = IW_MODE_ADHOC;
826                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
827                                                   &iwe, IW_EV_UINT_LEN);
828         }
829
830         memset(&iwe, 0, sizeof(iwe));
831         iwe.cmd = SIOCGIWFREQ;
832         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq);
833         iwe.u.freq.e = 0;
834         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
835                                           IW_EV_FREQ_LEN);
836
837         memset(&iwe, 0, sizeof(iwe));
838         iwe.cmd = SIOCGIWFREQ;
839         iwe.u.freq.m = bss->freq;
840         iwe.u.freq.e = 6;
841         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
842                                           IW_EV_FREQ_LEN);
843         memset(&iwe, 0, sizeof(iwe));
844         iwe.cmd = IWEVQUAL;
845         iwe.u.qual.qual = bss->qual;
846         iwe.u.qual.level = bss->signal;
847         iwe.u.qual.noise = bss->noise;
848         iwe.u.qual.updated = local->wstats_flags;
849         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
850                                           IW_EV_QUAL_LEN);
851
852         memset(&iwe, 0, sizeof(iwe));
853         iwe.cmd = SIOCGIWENCODE;
854         if (bss->capability & WLAN_CAPABILITY_PRIVACY)
855                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
856         else
857                 iwe.u.data.flags = IW_ENCODE_DISABLED;
858         iwe.u.data.length = 0;
859         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
860                                           &iwe, "");
861
862         ieee80211_scan_add_ies(info, bss, &current_ev, end_buf);
863
864         if (bss->supp_rates_len > 0) {
865                 /* display all supported rates in readable format */
866                 char *p = current_ev + iwe_stream_lcp_len(info);
867                 int i;
868
869                 memset(&iwe, 0, sizeof(iwe));
870                 iwe.cmd = SIOCGIWRATE;
871                 /* Those two flags are ignored... */
872                 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
873
874                 for (i = 0; i < bss->supp_rates_len; i++) {
875                         iwe.u.bitrate.value = ((bss->supp_rates[i] &
876                                                         0x7f) * 500000);
877                         p = iwe_stream_add_value(info, current_ev, p,
878                                         end_buf, &iwe, IW_EV_PARAM_LEN);
879                 }
880                 current_ev = p;
881         }
882
883         buf = kmalloc(30, GFP_ATOMIC);
884         if (buf) {
885                 memset(&iwe, 0, sizeof(iwe));
886                 iwe.cmd = IWEVCUSTOM;
887                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp));
888                 iwe.u.data.length = strlen(buf);
889                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
890                                                   &iwe, buf);
891                 memset(&iwe, 0, sizeof(iwe));
892                 iwe.cmd = IWEVCUSTOM;
893                 sprintf(buf, " Last beacon: %dms ago",
894                         jiffies_to_msecs(jiffies - bss->last_update));
895                 iwe.u.data.length = strlen(buf);
896                 current_ev = iwe_stream_add_point(info, current_ev,
897                                                   end_buf, &iwe, buf);
898                 kfree(buf);
899         }
900
901         if (bss_mesh_cfg(bss)) {
902                 u8 *cfg = bss_mesh_cfg(bss);
903                 buf = kmalloc(50, GFP_ATOMIC);
904                 if (buf) {
905                         memset(&iwe, 0, sizeof(iwe));
906                         iwe.cmd = IWEVCUSTOM;
907                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
908                         iwe.u.data.length = strlen(buf);
909                         current_ev = iwe_stream_add_point(info, current_ev,
910                                                           end_buf,
911                                                           &iwe, buf);
912                         sprintf(buf, "Path Selection Protocol ID: "
913                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
914                                                         cfg[4]);
915                         iwe.u.data.length = strlen(buf);
916                         current_ev = iwe_stream_add_point(info, current_ev,
917                                                           end_buf,
918                                                           &iwe, buf);
919                         sprintf(buf, "Path Selection Metric ID: "
920                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
921                                                         cfg[8]);
922                         iwe.u.data.length = strlen(buf);
923                         current_ev = iwe_stream_add_point(info, current_ev,
924                                                           end_buf,
925                                                           &iwe, buf);
926                         sprintf(buf, "Congestion Control Mode ID: "
927                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
928                                                         cfg[11], cfg[12]);
929                         iwe.u.data.length = strlen(buf);
930                         current_ev = iwe_stream_add_point(info, current_ev,
931                                                           end_buf,
932                                                           &iwe, buf);
933                         sprintf(buf, "Channel Precedence: "
934                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
935                                                         cfg[15], cfg[16]);
936                         iwe.u.data.length = strlen(buf);
937                         current_ev = iwe_stream_add_point(info, current_ev,
938                                                           end_buf,
939                                                           &iwe, buf);
940                         kfree(buf);
941                 }
942         }
943
944         return current_ev;
945 }
946
947
948 int ieee80211_scan_results(struct ieee80211_local *local,
949                            struct iw_request_info *info,
950                            char *buf, size_t len)
951 {
952         char *current_ev = buf;
953         char *end_buf = buf + len;
954         struct ieee80211_bss *bss;
955
956         spin_lock_bh(&local->bss_lock);
957         list_for_each_entry(bss, &local->bss_list, list) {
958                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
959                         spin_unlock_bh(&local->bss_lock);
960                         return -E2BIG;
961                 }
962                 current_ev = ieee80211_scan_result(local, info, bss,
963                                                        current_ev, end_buf);
964         }
965         spin_unlock_bh(&local->bss_lock);
966         return current_ev - buf;
967 }