cfg80211: connect/disconnect API
[linux-2.6.git] / net / wireless / core.c
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2009          Johannes Berg <johannes@sipsolutions.net>
5  */
6
7 #include <linux/if.h>
8 #include <linux/module.h>
9 #include <linux/err.h>
10 #include <linux/list.h>
11 #include <linux/nl80211.h>
12 #include <linux/debugfs.h>
13 #include <linux/notifier.h>
14 #include <linux/device.h>
15 #include <linux/rtnetlink.h>
16 #include <net/genetlink.h>
17 #include <net/cfg80211.h>
18 #include "nl80211.h"
19 #include "core.h"
20 #include "sysfs.h"
21 #include "debugfs.h"
22
23 /* name for sysfs, %d is appended */
24 #define PHY_NAME "phy"
25
26 MODULE_AUTHOR("Johannes Berg");
27 MODULE_LICENSE("GPL");
28 MODULE_DESCRIPTION("wireless configuration support");
29
30 /* RCU might be appropriate here since we usually
31  * only read the list, and that can happen quite
32  * often because we need to do it for each command */
33 LIST_HEAD(cfg80211_drv_list);
34
35 /*
36  * This is used to protect the cfg80211_drv_list, cfg80211_regdomain,
37  * country_ie_regdomain, the reg_beacon_list and the the last regulatory
38  * request receipt (last_request).
39  */
40 DEFINE_MUTEX(cfg80211_mutex);
41
42 /* for debugfs */
43 static struct dentry *ieee80211_debugfs_dir;
44
45 /* requires cfg80211_mutex to be held! */
46 struct cfg80211_registered_device *cfg80211_drv_by_wiphy_idx(int wiphy_idx)
47 {
48         struct cfg80211_registered_device *result = NULL, *drv;
49
50         if (!wiphy_idx_valid(wiphy_idx))
51                 return NULL;
52
53         assert_cfg80211_lock();
54
55         list_for_each_entry(drv, &cfg80211_drv_list, list) {
56                 if (drv->wiphy_idx == wiphy_idx) {
57                         result = drv;
58                         break;
59                 }
60         }
61
62         return result;
63 }
64
65 int get_wiphy_idx(struct wiphy *wiphy)
66 {
67         struct cfg80211_registered_device *drv;
68         if (!wiphy)
69                 return WIPHY_IDX_STALE;
70         drv = wiphy_to_dev(wiphy);
71         return drv->wiphy_idx;
72 }
73
74 /* requires cfg80211_drv_mutex to be held! */
75 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
76 {
77         struct cfg80211_registered_device *drv;
78
79         if (!wiphy_idx_valid(wiphy_idx))
80                 return NULL;
81
82         assert_cfg80211_lock();
83
84         drv = cfg80211_drv_by_wiphy_idx(wiphy_idx);
85         if (!drv)
86                 return NULL;
87         return &drv->wiphy;
88 }
89
90 /* requires cfg80211_mutex to be held! */
91 struct cfg80211_registered_device *
92 __cfg80211_drv_from_info(struct genl_info *info)
93 {
94         int ifindex;
95         struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
96         struct net_device *dev;
97         int err = -EINVAL;
98
99         assert_cfg80211_lock();
100
101         if (info->attrs[NL80211_ATTR_WIPHY]) {
102                 bywiphyidx = cfg80211_drv_by_wiphy_idx(
103                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
104                 err = -ENODEV;
105         }
106
107         if (info->attrs[NL80211_ATTR_IFINDEX]) {
108                 ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
109                 dev = dev_get_by_index(&init_net, ifindex);
110                 if (dev) {
111                         if (dev->ieee80211_ptr)
112                                 byifidx =
113                                         wiphy_to_dev(dev->ieee80211_ptr->wiphy);
114                         dev_put(dev);
115                 }
116                 err = -ENODEV;
117         }
118
119         if (bywiphyidx && byifidx) {
120                 if (bywiphyidx != byifidx)
121                         return ERR_PTR(-EINVAL);
122                 else
123                         return bywiphyidx; /* == byifidx */
124         }
125         if (bywiphyidx)
126                 return bywiphyidx;
127
128         if (byifidx)
129                 return byifidx;
130
131         return ERR_PTR(err);
132 }
133
134 struct cfg80211_registered_device *
135 cfg80211_get_dev_from_info(struct genl_info *info)
136 {
137         struct cfg80211_registered_device *drv;
138
139         mutex_lock(&cfg80211_mutex);
140         drv = __cfg80211_drv_from_info(info);
141
142         /* if it is not an error we grab the lock on
143          * it to assure it won't be going away while
144          * we operate on it */
145         if (!IS_ERR(drv))
146                 mutex_lock(&drv->mtx);
147
148         mutex_unlock(&cfg80211_mutex);
149
150         return drv;
151 }
152
153 struct cfg80211_registered_device *
154 cfg80211_get_dev_from_ifindex(int ifindex)
155 {
156         struct cfg80211_registered_device *drv = ERR_PTR(-ENODEV);
157         struct net_device *dev;
158
159         mutex_lock(&cfg80211_mutex);
160         dev = dev_get_by_index(&init_net, ifindex);
161         if (!dev)
162                 goto out;
163         if (dev->ieee80211_ptr) {
164                 drv = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
165                 mutex_lock(&drv->mtx);
166         } else
167                 drv = ERR_PTR(-ENODEV);
168         dev_put(dev);
169  out:
170         mutex_unlock(&cfg80211_mutex);
171         return drv;
172 }
173
174 void cfg80211_put_dev(struct cfg80211_registered_device *drv)
175 {
176         BUG_ON(IS_ERR(drv));
177         mutex_unlock(&drv->mtx);
178 }
179
180 /* requires cfg80211_mutex to be held */
181 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
182                         char *newname)
183 {
184         struct cfg80211_registered_device *drv;
185         int wiphy_idx, taken = -1, result, digits;
186
187         assert_cfg80211_lock();
188
189         /* prohibit calling the thing phy%d when %d is not its number */
190         sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
191         if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
192                 /* count number of places needed to print wiphy_idx */
193                 digits = 1;
194                 while (wiphy_idx /= 10)
195                         digits++;
196                 /*
197                  * deny the name if it is phy<idx> where <idx> is printed
198                  * without leading zeroes. taken == strlen(newname) here
199                  */
200                 if (taken == strlen(PHY_NAME) + digits)
201                         return -EINVAL;
202         }
203
204
205         /* Ignore nop renames */
206         if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
207                 return 0;
208
209         /* Ensure another device does not already have this name. */
210         list_for_each_entry(drv, &cfg80211_drv_list, list)
211                 if (strcmp(newname, dev_name(&drv->wiphy.dev)) == 0)
212                         return -EINVAL;
213
214         result = device_rename(&rdev->wiphy.dev, newname);
215         if (result)
216                 return result;
217
218         if (rdev->wiphy.debugfsdir &&
219             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
220                             rdev->wiphy.debugfsdir,
221                             rdev->wiphy.debugfsdir->d_parent,
222                             newname))
223                 printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
224                        newname);
225
226         nl80211_notify_dev_rename(rdev);
227
228         return 0;
229 }
230
231 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
232 {
233         struct cfg80211_registered_device *drv = data;
234
235         drv->ops->rfkill_poll(&drv->wiphy);
236 }
237
238 static int cfg80211_rfkill_set_block(void *data, bool blocked)
239 {
240         struct cfg80211_registered_device *drv = data;
241         struct wireless_dev *wdev;
242
243         if (!blocked)
244                 return 0;
245
246         rtnl_lock();
247         mutex_lock(&drv->devlist_mtx);
248
249         list_for_each_entry(wdev, &drv->netdev_list, list)
250                 dev_close(wdev->netdev);
251
252         mutex_unlock(&drv->devlist_mtx);
253         rtnl_unlock();
254
255         return 0;
256 }
257
258 static void cfg80211_rfkill_sync_work(struct work_struct *work)
259 {
260         struct cfg80211_registered_device *drv;
261
262         drv = container_of(work, struct cfg80211_registered_device, rfkill_sync);
263         cfg80211_rfkill_set_block(drv, rfkill_blocked(drv->rfkill));
264 }
265
266 /* exported functions */
267
268 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
269 {
270         static int wiphy_counter;
271
272         struct cfg80211_registered_device *drv;
273         int alloc_size;
274
275         WARN_ON(!ops->add_key && ops->del_key);
276         WARN_ON(ops->add_key && !ops->del_key);
277
278         alloc_size = sizeof(*drv) + sizeof_priv;
279
280         drv = kzalloc(alloc_size, GFP_KERNEL);
281         if (!drv)
282                 return NULL;
283
284         drv->ops = ops;
285
286         mutex_lock(&cfg80211_mutex);
287
288         drv->wiphy_idx = wiphy_counter++;
289
290         if (unlikely(!wiphy_idx_valid(drv->wiphy_idx))) {
291                 wiphy_counter--;
292                 mutex_unlock(&cfg80211_mutex);
293                 /* ugh, wrapped! */
294                 kfree(drv);
295                 return NULL;
296         }
297
298         mutex_unlock(&cfg80211_mutex);
299
300         /* give it a proper name */
301         dev_set_name(&drv->wiphy.dev, PHY_NAME "%d", drv->wiphy_idx);
302
303         mutex_init(&drv->mtx);
304         mutex_init(&drv->devlist_mtx);
305         INIT_LIST_HEAD(&drv->netdev_list);
306         spin_lock_init(&drv->bss_lock);
307         INIT_LIST_HEAD(&drv->bss_list);
308
309         device_initialize(&drv->wiphy.dev);
310         drv->wiphy.dev.class = &ieee80211_class;
311         drv->wiphy.dev.platform_data = drv;
312
313         drv->rfkill_ops.set_block = cfg80211_rfkill_set_block;
314         drv->rfkill = rfkill_alloc(dev_name(&drv->wiphy.dev),
315                                    &drv->wiphy.dev, RFKILL_TYPE_WLAN,
316                                    &drv->rfkill_ops, drv);
317
318         if (!drv->rfkill) {
319                 kfree(drv);
320                 return NULL;
321         }
322
323         INIT_WORK(&drv->rfkill_sync, cfg80211_rfkill_sync_work);
324
325         /*
326          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
327          * Fragmentation and RTS threshold are disabled by default with the
328          * special -1 value.
329          */
330         drv->wiphy.retry_short = 7;
331         drv->wiphy.retry_long = 4;
332         drv->wiphy.frag_threshold = (u32) -1;
333         drv->wiphy.rts_threshold = (u32) -1;
334
335         return &drv->wiphy;
336 }
337 EXPORT_SYMBOL(wiphy_new);
338
339 int wiphy_register(struct wiphy *wiphy)
340 {
341         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
342         int res;
343         enum ieee80211_band band;
344         struct ieee80211_supported_band *sband;
345         bool have_band = false;
346         int i;
347         u16 ifmodes = wiphy->interface_modes;
348
349         /* sanity check ifmodes */
350         WARN_ON(!ifmodes);
351         ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
352         if (WARN_ON(ifmodes != wiphy->interface_modes))
353                 wiphy->interface_modes = ifmodes;
354
355         /* sanity check supported bands/channels */
356         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
357                 sband = wiphy->bands[band];
358                 if (!sband)
359                         continue;
360
361                 sband->band = band;
362
363                 if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
364                         return -EINVAL;
365
366                 /*
367                  * Since we use a u32 for rate bitmaps in
368                  * ieee80211_get_response_rate, we cannot
369                  * have more than 32 legacy rates.
370                  */
371                 if (WARN_ON(sband->n_bitrates > 32))
372                         return -EINVAL;
373
374                 for (i = 0; i < sband->n_channels; i++) {
375                         sband->channels[i].orig_flags =
376                                 sband->channels[i].flags;
377                         sband->channels[i].orig_mag =
378                                 sband->channels[i].max_antenna_gain;
379                         sband->channels[i].orig_mpwr =
380                                 sband->channels[i].max_power;
381                         sband->channels[i].band = band;
382                 }
383
384                 have_band = true;
385         }
386
387         if (!have_band) {
388                 WARN_ON(1);
389                 return -EINVAL;
390         }
391
392         /* check and set up bitrates */
393         ieee80211_set_bitrate_flags(wiphy);
394
395         res = device_add(&drv->wiphy.dev);
396         if (res)
397                 return res;
398
399         res = rfkill_register(drv->rfkill);
400         if (res)
401                 goto out_rm_dev;
402
403         mutex_lock(&cfg80211_mutex);
404
405         /* set up regulatory info */
406         wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
407
408         list_add(&drv->list, &cfg80211_drv_list);
409
410         mutex_unlock(&cfg80211_mutex);
411
412         /* add to debugfs */
413         drv->wiphy.debugfsdir =
414                 debugfs_create_dir(wiphy_name(&drv->wiphy),
415                                    ieee80211_debugfs_dir);
416         if (IS_ERR(drv->wiphy.debugfsdir))
417                 drv->wiphy.debugfsdir = NULL;
418
419         if (wiphy->custom_regulatory) {
420                 struct regulatory_request request;
421
422                 request.wiphy_idx = get_wiphy_idx(wiphy);
423                 request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
424                 request.alpha2[0] = '9';
425                 request.alpha2[1] = '9';
426
427                 nl80211_send_reg_change_event(&request);
428         }
429
430         cfg80211_debugfs_drv_add(drv);
431
432         return 0;
433
434  out_rm_dev:
435         device_del(&drv->wiphy.dev);
436         return res;
437 }
438 EXPORT_SYMBOL(wiphy_register);
439
440 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
441 {
442         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
443
444         if (!drv->ops->rfkill_poll)
445                 return;
446         drv->rfkill_ops.poll = cfg80211_rfkill_poll;
447         rfkill_resume_polling(drv->rfkill);
448 }
449 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
450
451 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
452 {
453         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
454
455         rfkill_pause_polling(drv->rfkill);
456 }
457 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
458
459 void wiphy_unregister(struct wiphy *wiphy)
460 {
461         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
462
463         rfkill_unregister(drv->rfkill);
464
465         /* protect the device list */
466         mutex_lock(&cfg80211_mutex);
467
468         BUG_ON(!list_empty(&drv->netdev_list));
469
470         /*
471          * Try to grab drv->mtx. If a command is still in progress,
472          * hopefully the driver will refuse it since it's tearing
473          * down the device already. We wait for this command to complete
474          * before unlinking the item from the list.
475          * Note: as codified by the BUG_ON above we cannot get here if
476          * a virtual interface is still associated. Hence, we can only
477          * get to lock contention here if userspace issues a command
478          * that identified the hardware by wiphy index.
479          */
480         mutex_lock(&drv->mtx);
481         /* unlock again before freeing */
482         mutex_unlock(&drv->mtx);
483
484         cfg80211_debugfs_drv_del(drv);
485
486         /* If this device got a regulatory hint tell core its
487          * free to listen now to a new shiny device regulatory hint */
488         reg_device_remove(wiphy);
489
490         list_del(&drv->list);
491         device_del(&drv->wiphy.dev);
492         debugfs_remove(drv->wiphy.debugfsdir);
493
494         mutex_unlock(&cfg80211_mutex);
495 }
496 EXPORT_SYMBOL(wiphy_unregister);
497
498 void cfg80211_dev_free(struct cfg80211_registered_device *drv)
499 {
500         struct cfg80211_internal_bss *scan, *tmp;
501         rfkill_destroy(drv->rfkill);
502         mutex_destroy(&drv->mtx);
503         mutex_destroy(&drv->devlist_mtx);
504         list_for_each_entry_safe(scan, tmp, &drv->bss_list, list)
505                 cfg80211_put_bss(&scan->pub);
506         kfree(drv);
507 }
508
509 void wiphy_free(struct wiphy *wiphy)
510 {
511         put_device(&wiphy->dev);
512 }
513 EXPORT_SYMBOL(wiphy_free);
514
515 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
516 {
517         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
518
519         if (rfkill_set_hw_state(drv->rfkill, blocked))
520                 schedule_work(&drv->rfkill_sync);
521 }
522 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
523
524 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
525                                          unsigned long state,
526                                          void *ndev)
527 {
528         struct net_device *dev = ndev;
529         struct wireless_dev *wdev = dev->ieee80211_ptr;
530         struct cfg80211_registered_device *rdev;
531
532         if (!wdev)
533                 return NOTIFY_DONE;
534
535         rdev = wiphy_to_dev(wdev->wiphy);
536
537         WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
538
539         switch (state) {
540         case NETDEV_REGISTER:
541                 mutex_lock(&rdev->devlist_mtx);
542                 list_add(&wdev->list, &rdev->netdev_list);
543                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
544                                       "phy80211")) {
545                         printk(KERN_ERR "wireless: failed to add phy80211 "
546                                 "symlink to netdev!\n");
547                 }
548                 wdev->netdev = dev;
549                 wdev->sme_state = CFG80211_SME_IDLE;
550 #ifdef CONFIG_WIRELESS_EXT
551                 wdev->wext.default_key = -1;
552                 wdev->wext.default_mgmt_key = -1;
553 #endif
554                 mutex_unlock(&rdev->devlist_mtx);
555                 break;
556         case NETDEV_GOING_DOWN:
557                 if (!wdev->ssid_len)
558                         break;
559
560                 switch (wdev->iftype) {
561                 case NL80211_IFTYPE_ADHOC:
562                         cfg80211_leave_ibss(rdev, dev, true);
563                         break;
564                 case NL80211_IFTYPE_STATION:
565                         cfg80211_disconnect(rdev, dev,
566                                             WLAN_REASON_DEAUTH_LEAVING);
567                         break;
568                 default:
569                         break;
570                 }
571                 break;
572         case NETDEV_UP:
573 #ifdef CONFIG_WIRELESS_EXT
574                 if (wdev->iftype != NL80211_IFTYPE_ADHOC)
575                         break;
576                 if (!wdev->wext.ibss.ssid_len)
577                         break;
578                 cfg80211_join_ibss(rdev, dev, &wdev->wext.ibss);
579 #endif
580                 break;
581         case NETDEV_UNREGISTER:
582                 mutex_lock(&rdev->devlist_mtx);
583                 if (!list_empty(&wdev->list)) {
584                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
585                         list_del_init(&wdev->list);
586                 }
587                 mutex_unlock(&rdev->devlist_mtx);
588                 break;
589         case NETDEV_PRE_UP:
590                 if (rfkill_blocked(rdev->rfkill))
591                         return notifier_from_errno(-ERFKILL);
592                 break;
593         }
594
595         return NOTIFY_DONE;
596 }
597
598 static struct notifier_block cfg80211_netdev_notifier = {
599         .notifier_call = cfg80211_netdev_notifier_call,
600 };
601
602 static int cfg80211_init(void)
603 {
604         int err;
605
606         err = wiphy_sysfs_init();
607         if (err)
608                 goto out_fail_sysfs;
609
610         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
611         if (err)
612                 goto out_fail_notifier;
613
614         err = nl80211_init();
615         if (err)
616                 goto out_fail_nl80211;
617
618         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
619
620         err = regulatory_init();
621         if (err)
622                 goto out_fail_reg;
623
624         return 0;
625
626 out_fail_reg:
627         debugfs_remove(ieee80211_debugfs_dir);
628 out_fail_nl80211:
629         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
630 out_fail_notifier:
631         wiphy_sysfs_exit();
632 out_fail_sysfs:
633         return err;
634 }
635
636 subsys_initcall(cfg80211_init);
637
638 static void cfg80211_exit(void)
639 {
640         debugfs_remove(ieee80211_debugfs_dir);
641         nl80211_exit();
642         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
643         wiphy_sysfs_exit();
644         regulatory_exit();
645 }
646 module_exit(cfg80211_exit);