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