27727027d76d31246e2fa7dacc6e415ce6dc0135
[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->sta_bss_lock);
36         INIT_LIST_HEAD(&local->sta_bss_list);
37 }
38
39 void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local)
40 {
41         struct ieee80211_sta_bss *bss, *tmp;
42
43         list_for_each_entry_safe(bss, tmp, &local->sta_bss_list, list)
44                 ieee80211_rx_bss_put(local, bss);
45 }
46
47 struct ieee80211_sta_bss *
48 ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
49                      u8 *ssid, u8 ssid_len)
50 {
51         struct ieee80211_sta_bss *bss;
52
53         spin_lock_bh(&local->sta_bss_lock);
54         bss = local->sta_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->sta_bss_lock);
67         return bss;
68 }
69
70 /* Caller must hold local->sta_bss_lock */
71 static void __ieee80211_rx_bss_hash_add(struct ieee80211_local *local,
72                                         struct ieee80211_sta_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->sta_bss_hash[hash_idx];
83         local->sta_bss_hash[hash_idx] = bss;
84 }
85
86 /* Caller must hold local->sta_bss_lock */
87 static void __ieee80211_rx_bss_hash_del(struct ieee80211_local *local,
88                                         struct ieee80211_sta_bss *bss)
89 {
90         struct ieee80211_sta_bss *b, *prev = NULL;
91         b = local->sta_bss_hash[STA_HASH(bss->bssid)];
92         while (b) {
93                 if (b == bss) {
94                         if (!prev)
95                                 local->sta_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_sta_bss *
107 ieee80211_rx_bss_add(struct ieee80211_local *local, u8 *bssid, int freq,
108                      u8 *ssid, u8 ssid_len)
109 {
110         struct ieee80211_sta_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->sta_bss_lock);
124         /* TODO: order by RSSI? */
125         list_add_tail(&bss->list, &local->sta_bss_list);
126         __ieee80211_rx_bss_hash_add(local, bss);
127         spin_unlock_bh(&local->sta_bss_lock);
128         return bss;
129 }
130
131 #ifdef CONFIG_MAC80211_MESH
132 static struct ieee80211_sta_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_sta_bss *bss;
137
138         spin_lock_bh(&local->sta_bss_lock);
139         bss = local->sta_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->sta_bss_lock);
153         return bss;
154 }
155
156 static struct ieee80211_sta_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_sta_bss *bss;
161
162         if (mesh_config_len != MESH_CFG_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->sta_bss_lock);
190         /* TODO: order by RSSI? */
191         list_add_tail(&bss->list, &local->sta_bss_list);
192         __ieee80211_rx_bss_hash_add(local, bss);
193         spin_unlock_bh(&local->sta_bss_lock);
194         return bss;
195 }
196 #endif
197
198 static void ieee80211_rx_bss_free(struct ieee80211_sta_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_sta_bss *bss)
208 {
209         local_bh_disable();
210         if (!atomic_dec_and_lock(&bss->users, &local->sta_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->sta_bss_lock);
218         ieee80211_rx_bss_free(bss);
219 }
220
221 struct ieee80211_sta_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_sta_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->sta_bss_lock);
256                 list_move_tail(&bss->list, &local->sta_bss_list);
257                 spin_unlock_bh(&local->sta_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_sta_rx_scan(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_sta_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         ieee80211_rx_bss_put(sdata->local, bss);
392
393         dev_kfree_skb(skb);
394         return RX_QUEUED;
395 }
396
397 static void ieee80211_send_nullfunc(struct ieee80211_local *local,
398                                     struct ieee80211_sub_if_data *sdata,
399                                     int powersave)
400 {
401         struct sk_buff *skb;
402         struct ieee80211_hdr *nullfunc;
403         __le16 fc;
404
405         skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
406         if (!skb) {
407                 printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
408                        "frame\n", sdata->dev->name);
409                 return;
410         }
411         skb_reserve(skb, local->hw.extra_tx_headroom);
412
413         nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
414         memset(nullfunc, 0, 24);
415         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
416                          IEEE80211_FCTL_TODS);
417         if (powersave)
418                 fc |= cpu_to_le16(IEEE80211_FCTL_PM);
419         nullfunc->frame_control = fc;
420         memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
421         memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
422         memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
423
424         ieee80211_tx_skb(sdata, skb, 0);
425 }
426
427 void ieee80211_scan_completed(struct ieee80211_hw *hw)
428 {
429         struct ieee80211_local *local = hw_to_local(hw);
430         struct ieee80211_sub_if_data *sdata;
431         union iwreq_data wrqu;
432
433         if (WARN_ON(!local->sta_hw_scanning && !local->sta_sw_scanning))
434                 return;
435
436         local->last_scan_completed = jiffies;
437         memset(&wrqu, 0, sizeof(wrqu));
438
439         /*
440          * local->scan_sdata could have been NULLed by the interface
441          * down code in case we were scanning on an interface that is
442          * being taken down.
443          */
444         sdata = local->scan_sdata;
445         if (sdata)
446                 wireless_send_event(sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
447
448         if (local->sta_hw_scanning) {
449                 local->sta_hw_scanning = 0;
450                 if (ieee80211_hw_config(local))
451                         printk(KERN_DEBUG "%s: failed to restore operational "
452                                "channel after scan\n", wiphy_name(local->hw.wiphy));
453
454                 goto done;
455         }
456
457         local->sta_sw_scanning = 0;
458         if (ieee80211_hw_config(local))
459                 printk(KERN_DEBUG "%s: failed to restore operational "
460                        "channel after scan\n", wiphy_name(local->hw.wiphy));
461
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 == IEEE80211_IF_TYPE_STA) {
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_sta_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 == IEEE80211_IF_TYPE_IBSS &&
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                                 printk(KERN_DEBUG "%s: failed to set freq to "
550                                        "%d MHz for scan\n", wiphy_name(local->hw.wiphy),
551                                        chan->center_freq);
552                                 skip = 1;
553                         }
554                 }
555
556                 /* advance state machine to next channel/band */
557                 local->scan_channel_idx++;
558                 if (local->scan_channel_idx >= sband->n_channels) {
559                         /*
560                          * scan_band may end up == IEEE80211_NUM_BANDS, but
561                          * we'll catch that case above and complete the scan
562                          * if that is the case.
563                          */
564                         local->scan_band++;
565                         local->scan_channel_idx = 0;
566                 }
567
568                 if (skip)
569                         break;
570
571                 next_delay = IEEE80211_PROBE_DELAY +
572                              usecs_to_jiffies(local->hw.channel_change_time);
573                 local->scan_state = SCAN_SEND_PROBE;
574                 break;
575         case SCAN_SEND_PROBE:
576                 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
577                 local->scan_state = SCAN_SET_CHANNEL;
578
579                 if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN)
580                         break;
581                 ieee80211_send_probe_req(sdata, NULL, local->scan_ssid,
582                                          local->scan_ssid_len);
583                 next_delay = IEEE80211_CHANNEL_TIME;
584                 break;
585         }
586
587         queue_delayed_work(local->hw.workqueue, &local->scan_work,
588                            next_delay);
589 }
590
591
592 int ieee80211_sta_start_scan(struct ieee80211_sub_if_data *scan_sdata,
593                              u8 *ssid, size_t ssid_len)
594 {
595         struct ieee80211_local *local = scan_sdata->local;
596         struct ieee80211_sub_if_data *sdata;
597
598         if (ssid_len > IEEE80211_MAX_SSID_LEN)
599                 return -EINVAL;
600
601         /* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
602          * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
603          * BSSID: MACAddress
604          * SSID
605          * ScanType: ACTIVE, PASSIVE
606          * ProbeDelay: delay (in microseconds) to be used prior to transmitting
607          *    a Probe frame during active scanning
608          * ChannelList
609          * MinChannelTime (>= ProbeDelay), in TU
610          * MaxChannelTime: (>= MinChannelTime), in TU
611          */
612
613          /* MLME-SCAN.confirm
614           * BSSDescriptionSet
615           * ResultCode: SUCCESS, INVALID_PARAMETERS
616          */
617
618         if (local->sta_sw_scanning || local->sta_hw_scanning) {
619                 if (local->scan_sdata == scan_sdata)
620                         return 0;
621                 return -EBUSY;
622         }
623
624         if (local->ops->hw_scan) {
625                 int rc;
626
627                 local->sta_hw_scanning = 1;
628                 rc = local->ops->hw_scan(local_to_hw(local), ssid, ssid_len);
629                 if (rc) {
630                         local->sta_hw_scanning = 0;
631                         return rc;
632                 }
633                 local->scan_sdata = scan_sdata;
634                 return 0;
635         }
636
637         local->sta_sw_scanning = 1;
638
639         rcu_read_lock();
640         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
641                 if (sdata->vif.type == IEEE80211_IF_TYPE_STA) {
642                         if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
643                                 netif_tx_stop_all_queues(sdata->dev);
644                                 ieee80211_send_nullfunc(local, sdata, 1);
645                         }
646                 } else
647                         netif_tx_stop_all_queues(sdata->dev);
648         }
649         rcu_read_unlock();
650
651         if (ssid) {
652                 local->scan_ssid_len = ssid_len;
653                 memcpy(local->scan_ssid, ssid, ssid_len);
654         } else
655                 local->scan_ssid_len = 0;
656         local->scan_state = SCAN_SET_CHANNEL;
657         local->scan_channel_idx = 0;
658         local->scan_band = IEEE80211_BAND_2GHZ;
659         local->scan_sdata = scan_sdata;
660
661         netif_addr_lock_bh(local->mdev);
662         local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
663         local->ops->configure_filter(local_to_hw(local),
664                                      FIF_BCN_PRBRESP_PROMISC,
665                                      &local->filter_flags,
666                                      local->mdev->mc_count,
667                                      local->mdev->mc_list);
668         netif_addr_unlock_bh(local->mdev);
669
670         /* TODO: start scan as soon as all nullfunc frames are ACKed */
671         queue_delayed_work(local->hw.workqueue, &local->scan_work,
672                            IEEE80211_CHANNEL_TIME);
673
674         return 0;
675 }
676
677
678 int ieee80211_sta_req_scan(struct ieee80211_sub_if_data *sdata, u8 *ssid, size_t ssid_len)
679 {
680         struct ieee80211_local *local = sdata->local;
681         struct ieee80211_if_sta *ifsta;
682
683         if (sdata->vif.type != IEEE80211_IF_TYPE_STA)
684                 return ieee80211_sta_start_scan(sdata, ssid, ssid_len);
685
686         /*
687          * STA has a state machine that might need to defer scanning
688          * while it's trying to associate/authenticate, therefore we
689          * queue it up to the state machine in that case.
690          */
691
692         if (local->sta_sw_scanning || local->sta_hw_scanning) {
693                 if (local->scan_sdata == sdata)
694                         return 0;
695                 return -EBUSY;
696         }
697
698         ifsta = &sdata->u.sta;
699
700         ifsta->scan_ssid_len = ssid_len;
701         if (ssid_len)
702                 memcpy(ifsta->scan_ssid, ssid, ssid_len);
703         set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
704         queue_work(local->hw.workqueue, &ifsta->work);
705
706         return 0;
707 }
708
709
710 static void ieee80211_sta_add_scan_ies(struct iw_request_info *info,
711                                        struct ieee80211_sta_bss *bss,
712                                        char **current_ev, char *end_buf)
713 {
714         u8 *pos, *end, *next;
715         struct iw_event iwe;
716
717         if (bss == NULL || bss->ies == NULL)
718                 return;
719
720         /*
721          * If needed, fragment the IEs buffer (at IE boundaries) into short
722          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
723          */
724         pos = bss->ies;
725         end = pos + bss->ies_len;
726
727         while (end - pos > IW_GENERIC_IE_MAX) {
728                 next = pos + 2 + pos[1];
729                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
730                         next = next + 2 + next[1];
731
732                 memset(&iwe, 0, sizeof(iwe));
733                 iwe.cmd = IWEVGENIE;
734                 iwe.u.data.length = next - pos;
735                 *current_ev = iwe_stream_add_point(info, *current_ev,
736                                                    end_buf, &iwe, pos);
737
738                 pos = next;
739         }
740
741         if (end > pos) {
742                 memset(&iwe, 0, sizeof(iwe));
743                 iwe.cmd = IWEVGENIE;
744                 iwe.u.data.length = end - pos;
745                 *current_ev = iwe_stream_add_point(info, *current_ev,
746                                                    end_buf, &iwe, pos);
747         }
748 }
749
750
751 static char *
752 ieee80211_sta_scan_result(struct ieee80211_local *local,
753                           struct iw_request_info *info,
754                           struct ieee80211_sta_bss *bss,
755                           char *current_ev, char *end_buf)
756 {
757         struct iw_event iwe;
758         char *buf;
759
760         if (time_after(jiffies,
761                        bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE))
762                 return current_ev;
763
764         memset(&iwe, 0, sizeof(iwe));
765         iwe.cmd = SIOCGIWAP;
766         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
767         memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN);
768         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
769                                           IW_EV_ADDR_LEN);
770
771         memset(&iwe, 0, sizeof(iwe));
772         iwe.cmd = SIOCGIWESSID;
773         if (bss_mesh_cfg(bss)) {
774                 iwe.u.data.length = bss_mesh_id_len(bss);
775                 iwe.u.data.flags = 1;
776                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
777                                                   &iwe, bss_mesh_id(bss));
778         } else {
779                 iwe.u.data.length = bss->ssid_len;
780                 iwe.u.data.flags = 1;
781                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
782                                                   &iwe, bss->ssid);
783         }
784
785         if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
786             || bss_mesh_cfg(bss)) {
787                 memset(&iwe, 0, sizeof(iwe));
788                 iwe.cmd = SIOCGIWMODE;
789                 if (bss_mesh_cfg(bss))
790                         iwe.u.mode = IW_MODE_MESH;
791                 else if (bss->capability & WLAN_CAPABILITY_ESS)
792                         iwe.u.mode = IW_MODE_MASTER;
793                 else
794                         iwe.u.mode = IW_MODE_ADHOC;
795                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
796                                                   &iwe, IW_EV_UINT_LEN);
797         }
798
799         memset(&iwe, 0, sizeof(iwe));
800         iwe.cmd = SIOCGIWFREQ;
801         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq);
802         iwe.u.freq.e = 0;
803         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
804                                           IW_EV_FREQ_LEN);
805
806         memset(&iwe, 0, sizeof(iwe));
807         iwe.cmd = SIOCGIWFREQ;
808         iwe.u.freq.m = bss->freq;
809         iwe.u.freq.e = 6;
810         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
811                                           IW_EV_FREQ_LEN);
812         memset(&iwe, 0, sizeof(iwe));
813         iwe.cmd = IWEVQUAL;
814         iwe.u.qual.qual = bss->qual;
815         iwe.u.qual.level = bss->signal;
816         iwe.u.qual.noise = bss->noise;
817         iwe.u.qual.updated = local->wstats_flags;
818         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
819                                           IW_EV_QUAL_LEN);
820
821         memset(&iwe, 0, sizeof(iwe));
822         iwe.cmd = SIOCGIWENCODE;
823         if (bss->capability & WLAN_CAPABILITY_PRIVACY)
824                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
825         else
826                 iwe.u.data.flags = IW_ENCODE_DISABLED;
827         iwe.u.data.length = 0;
828         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
829                                           &iwe, "");
830
831         ieee80211_sta_add_scan_ies(info, bss, &current_ev, end_buf);
832
833         if (bss->supp_rates_len > 0) {
834                 /* display all supported rates in readable format */
835                 char *p = current_ev + iwe_stream_lcp_len(info);
836                 int i;
837
838                 memset(&iwe, 0, sizeof(iwe));
839                 iwe.cmd = SIOCGIWRATE;
840                 /* Those two flags are ignored... */
841                 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
842
843                 for (i = 0; i < bss->supp_rates_len; i++) {
844                         iwe.u.bitrate.value = ((bss->supp_rates[i] &
845                                                         0x7f) * 500000);
846                         p = iwe_stream_add_value(info, current_ev, p,
847                                         end_buf, &iwe, IW_EV_PARAM_LEN);
848                 }
849                 current_ev = p;
850         }
851
852         buf = kmalloc(30, GFP_ATOMIC);
853         if (buf) {
854                 memset(&iwe, 0, sizeof(iwe));
855                 iwe.cmd = IWEVCUSTOM;
856                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp));
857                 iwe.u.data.length = strlen(buf);
858                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
859                                                   &iwe, buf);
860                 memset(&iwe, 0, sizeof(iwe));
861                 iwe.cmd = IWEVCUSTOM;
862                 sprintf(buf, " Last beacon: %dms ago",
863                         jiffies_to_msecs(jiffies - bss->last_update));
864                 iwe.u.data.length = strlen(buf);
865                 current_ev = iwe_stream_add_point(info, current_ev,
866                                                   end_buf, &iwe, buf);
867                 kfree(buf);
868         }
869
870         if (bss_mesh_cfg(bss)) {
871                 u8 *cfg = bss_mesh_cfg(bss);
872                 buf = kmalloc(50, GFP_ATOMIC);
873                 if (buf) {
874                         memset(&iwe, 0, sizeof(iwe));
875                         iwe.cmd = IWEVCUSTOM;
876                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
877                         iwe.u.data.length = strlen(buf);
878                         current_ev = iwe_stream_add_point(info, current_ev,
879                                                           end_buf,
880                                                           &iwe, buf);
881                         sprintf(buf, "Path Selection Protocol ID: "
882                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
883                                                         cfg[4]);
884                         iwe.u.data.length = strlen(buf);
885                         current_ev = iwe_stream_add_point(info, current_ev,
886                                                           end_buf,
887                                                           &iwe, buf);
888                         sprintf(buf, "Path Selection Metric ID: "
889                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
890                                                         cfg[8]);
891                         iwe.u.data.length = strlen(buf);
892                         current_ev = iwe_stream_add_point(info, current_ev,
893                                                           end_buf,
894                                                           &iwe, buf);
895                         sprintf(buf, "Congestion Control Mode ID: "
896                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
897                                                         cfg[11], cfg[12]);
898                         iwe.u.data.length = strlen(buf);
899                         current_ev = iwe_stream_add_point(info, current_ev,
900                                                           end_buf,
901                                                           &iwe, buf);
902                         sprintf(buf, "Channel Precedence: "
903                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
904                                                         cfg[15], cfg[16]);
905                         iwe.u.data.length = strlen(buf);
906                         current_ev = iwe_stream_add_point(info, current_ev,
907                                                           end_buf,
908                                                           &iwe, buf);
909                         kfree(buf);
910                 }
911         }
912
913         return current_ev;
914 }
915
916
917 int ieee80211_sta_scan_results(struct ieee80211_local *local,
918                                struct iw_request_info *info,
919                                char *buf, size_t len)
920 {
921         char *current_ev = buf;
922         char *end_buf = buf + len;
923         struct ieee80211_sta_bss *bss;
924
925         spin_lock_bh(&local->sta_bss_lock);
926         list_for_each_entry(bss, &local->sta_bss_list, list) {
927                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
928                         spin_unlock_bh(&local->sta_bss_lock);
929                         return -E2BIG;
930                 }
931                 current_ev = ieee80211_sta_scan_result(local, info, bss,
932                                                        current_ev, end_buf);
933         }
934         spin_unlock_bh(&local->sta_bss_lock);
935         return current_ev - buf;
936 }