lib80211: silence excessive crypto debugging messages
[linux-3.10.git] / net / wireless / core.c
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2008          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/mutex.h>
11 #include <linux/list.h>
12 #include <linux/nl80211.h>
13 #include <linux/debugfs.h>
14 #include <linux/notifier.h>
15 #include <linux/device.h>
16 #include <net/genetlink.h>
17 #include <net/cfg80211.h>
18 #include <net/wireless.h>
19 #include "nl80211.h"
20 #include "core.h"
21 #include "sysfs.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 DEFINE_MUTEX(cfg80211_drv_mutex);
35
36 /* for debugfs */
37 static struct dentry *ieee80211_debugfs_dir;
38
39 /* requires cfg80211_drv_mutex to be held! */
40 static struct cfg80211_registered_device *cfg80211_drv_by_wiphy(int wiphy)
41 {
42         struct cfg80211_registered_device *result = NULL, *drv;
43
44         list_for_each_entry(drv, &cfg80211_drv_list, list) {
45                 if (drv->idx == wiphy) {
46                         result = drv;
47                         break;
48                 }
49         }
50
51         return result;
52 }
53
54 /* requires cfg80211_drv_mutex to be held! */
55 static struct cfg80211_registered_device *
56 __cfg80211_drv_from_info(struct genl_info *info)
57 {
58         int ifindex;
59         struct cfg80211_registered_device *bywiphy = NULL, *byifidx = NULL;
60         struct net_device *dev;
61         int err = -EINVAL;
62
63         if (info->attrs[NL80211_ATTR_WIPHY]) {
64                 bywiphy = cfg80211_drv_by_wiphy(
65                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
66                 err = -ENODEV;
67         }
68
69         if (info->attrs[NL80211_ATTR_IFINDEX]) {
70                 ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
71                 dev = dev_get_by_index(&init_net, ifindex);
72                 if (dev) {
73                         if (dev->ieee80211_ptr)
74                                 byifidx =
75                                         wiphy_to_dev(dev->ieee80211_ptr->wiphy);
76                         dev_put(dev);
77                 }
78                 err = -ENODEV;
79         }
80
81         if (bywiphy && byifidx) {
82                 if (bywiphy != byifidx)
83                         return ERR_PTR(-EINVAL);
84                 else
85                         return bywiphy; /* == byifidx */
86         }
87         if (bywiphy)
88                 return bywiphy;
89
90         if (byifidx)
91                 return byifidx;
92
93         return ERR_PTR(err);
94 }
95
96 struct cfg80211_registered_device *
97 cfg80211_get_dev_from_info(struct genl_info *info)
98 {
99         struct cfg80211_registered_device *drv;
100
101         mutex_lock(&cfg80211_drv_mutex);
102         drv = __cfg80211_drv_from_info(info);
103
104         /* if it is not an error we grab the lock on
105          * it to assure it won't be going away while
106          * we operate on it */
107         if (!IS_ERR(drv))
108                 mutex_lock(&drv->mtx);
109
110         mutex_unlock(&cfg80211_drv_mutex);
111
112         return drv;
113 }
114
115 struct cfg80211_registered_device *
116 cfg80211_get_dev_from_ifindex(int ifindex)
117 {
118         struct cfg80211_registered_device *drv = ERR_PTR(-ENODEV);
119         struct net_device *dev;
120
121         mutex_lock(&cfg80211_drv_mutex);
122         dev = dev_get_by_index(&init_net, ifindex);
123         if (!dev)
124                 goto out;
125         if (dev->ieee80211_ptr) {
126                 drv = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
127                 mutex_lock(&drv->mtx);
128         } else
129                 drv = ERR_PTR(-ENODEV);
130         dev_put(dev);
131  out:
132         mutex_unlock(&cfg80211_drv_mutex);
133         return drv;
134 }
135
136 void cfg80211_put_dev(struct cfg80211_registered_device *drv)
137 {
138         BUG_ON(IS_ERR(drv));
139         mutex_unlock(&drv->mtx);
140 }
141
142 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
143                         char *newname)
144 {
145         struct cfg80211_registered_device *drv;
146         int idx, taken = -1, result, digits;
147
148         mutex_lock(&cfg80211_drv_mutex);
149
150         /* prohibit calling the thing phy%d when %d is not its number */
151         sscanf(newname, PHY_NAME "%d%n", &idx, &taken);
152         if (taken == strlen(newname) && idx != rdev->idx) {
153                 /* count number of places needed to print idx */
154                 digits = 1;
155                 while (idx /= 10)
156                         digits++;
157                 /*
158                  * deny the name if it is phy<idx> where <idx> is printed
159                  * without leading zeroes. taken == strlen(newname) here
160                  */
161                 result = -EINVAL;
162                 if (taken == strlen(PHY_NAME) + digits)
163                         goto out_unlock;
164         }
165
166
167         /* Ignore nop renames */
168         result = 0;
169         if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
170                 goto out_unlock;
171
172         /* Ensure another device does not already have this name. */
173         list_for_each_entry(drv, &cfg80211_drv_list, list) {
174                 result = -EINVAL;
175                 if (strcmp(newname, dev_name(&drv->wiphy.dev)) == 0)
176                         goto out_unlock;
177         }
178
179         /* this will only check for collisions in sysfs
180          * which is not even always compiled in.
181          */
182         result = device_rename(&rdev->wiphy.dev, newname);
183         if (result)
184                 goto out_unlock;
185
186         if (rdev->wiphy.debugfsdir &&
187             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
188                             rdev->wiphy.debugfsdir,
189                             rdev->wiphy.debugfsdir->d_parent,
190                             newname))
191                 printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
192                        newname);
193
194         result = 0;
195 out_unlock:
196         mutex_unlock(&cfg80211_drv_mutex);
197         if (result == 0)
198                 nl80211_notify_dev_rename(rdev);
199
200         return result;
201 }
202
203 /* exported functions */
204
205 struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
206 {
207         static int wiphy_counter;
208
209         struct cfg80211_registered_device *drv;
210         int alloc_size;
211
212         WARN_ON(!ops->add_key && ops->del_key);
213         WARN_ON(ops->add_key && !ops->del_key);
214
215         alloc_size = sizeof(*drv) + sizeof_priv;
216
217         drv = kzalloc(alloc_size, GFP_KERNEL);
218         if (!drv)
219                 return NULL;
220
221         drv->ops = ops;
222
223         mutex_lock(&cfg80211_drv_mutex);
224
225         drv->idx = wiphy_counter++;
226
227         if (unlikely(drv->idx < 0)) {
228                 wiphy_counter--;
229                 mutex_unlock(&cfg80211_drv_mutex);
230                 /* ugh, wrapped! */
231                 kfree(drv);
232                 return NULL;
233         }
234
235         mutex_unlock(&cfg80211_drv_mutex);
236
237         /* give it a proper name */
238         dev_set_name(&drv->wiphy.dev, PHY_NAME "%d", drv->idx);
239
240         mutex_init(&drv->mtx);
241         mutex_init(&drv->devlist_mtx);
242         INIT_LIST_HEAD(&drv->netdev_list);
243
244         device_initialize(&drv->wiphy.dev);
245         drv->wiphy.dev.class = &ieee80211_class;
246         drv->wiphy.dev.platform_data = drv;
247
248         return &drv->wiphy;
249 }
250 EXPORT_SYMBOL(wiphy_new);
251
252 int wiphy_register(struct wiphy *wiphy)
253 {
254         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
255         int res;
256         enum ieee80211_band band;
257         struct ieee80211_supported_band *sband;
258         bool have_band = false;
259         int i;
260         u16 ifmodes = wiphy->interface_modes;
261
262         /* sanity check ifmodes */
263         WARN_ON(!ifmodes);
264         ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
265         if (WARN_ON(ifmodes != wiphy->interface_modes))
266                 wiphy->interface_modes = ifmodes;
267
268         /* sanity check supported bands/channels */
269         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
270                 sband = wiphy->bands[band];
271                 if (!sband)
272                         continue;
273
274                 sband->band = band;
275
276                 if (!sband->n_channels || !sband->n_bitrates) {
277                         WARN_ON(1);
278                         return -EINVAL;
279                 }
280
281                 for (i = 0; i < sband->n_channels; i++) {
282                         sband->channels[i].orig_flags =
283                                 sband->channels[i].flags;
284                         sband->channels[i].orig_mag =
285                                 sband->channels[i].max_antenna_gain;
286                         sband->channels[i].orig_mpwr =
287                                 sband->channels[i].max_power;
288                         sband->channels[i].band = band;
289                 }
290
291                 have_band = true;
292         }
293
294         if (!have_band) {
295                 WARN_ON(1);
296                 return -EINVAL;
297         }
298
299         /* check and set up bitrates */
300         ieee80211_set_bitrate_flags(wiphy);
301
302         mutex_lock(&cfg80211_drv_mutex);
303
304         /* set up regulatory info */
305         wiphy_update_regulatory(wiphy, REGDOM_SET_BY_CORE);
306
307         res = device_add(&drv->wiphy.dev);
308         if (res)
309                 goto out_unlock;
310
311         list_add(&drv->list, &cfg80211_drv_list);
312
313         /* add to debugfs */
314         drv->wiphy.debugfsdir =
315                 debugfs_create_dir(wiphy_name(&drv->wiphy),
316                                    ieee80211_debugfs_dir);
317         if (IS_ERR(drv->wiphy.debugfsdir))
318                 drv->wiphy.debugfsdir = NULL;
319
320         res = 0;
321 out_unlock:
322         mutex_unlock(&cfg80211_drv_mutex);
323         return res;
324 }
325 EXPORT_SYMBOL(wiphy_register);
326
327 void wiphy_unregister(struct wiphy *wiphy)
328 {
329         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
330
331         /* protect the device list */
332         mutex_lock(&cfg80211_drv_mutex);
333
334         BUG_ON(!list_empty(&drv->netdev_list));
335
336         /*
337          * Try to grab drv->mtx. If a command is still in progress,
338          * hopefully the driver will refuse it since it's tearing
339          * down the device already. We wait for this command to complete
340          * before unlinking the item from the list.
341          * Note: as codified by the BUG_ON above we cannot get here if
342          * a virtual interface is still associated. Hence, we can only
343          * get to lock contention here if userspace issues a command
344          * that identified the hardware by wiphy index.
345          */
346         mutex_lock(&drv->mtx);
347         /* unlock again before freeing */
348         mutex_unlock(&drv->mtx);
349
350         /* If this device got a regulatory hint tell core its
351          * free to listen now to a new shiny device regulatory hint */
352         reg_device_remove(wiphy);
353
354         list_del(&drv->list);
355         device_del(&drv->wiphy.dev);
356         debugfs_remove(drv->wiphy.debugfsdir);
357
358         mutex_unlock(&cfg80211_drv_mutex);
359 }
360 EXPORT_SYMBOL(wiphy_unregister);
361
362 void cfg80211_dev_free(struct cfg80211_registered_device *drv)
363 {
364         mutex_destroy(&drv->mtx);
365         mutex_destroy(&drv->devlist_mtx);
366         kfree(drv);
367 }
368
369 void wiphy_free(struct wiphy *wiphy)
370 {
371         put_device(&wiphy->dev);
372 }
373 EXPORT_SYMBOL(wiphy_free);
374
375 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
376                                          unsigned long state,
377                                          void *ndev)
378 {
379         struct net_device *dev = ndev;
380         struct cfg80211_registered_device *rdev;
381
382         if (!dev->ieee80211_ptr)
383                 return 0;
384
385         rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
386
387         WARN_ON(dev->ieee80211_ptr->iftype == NL80211_IFTYPE_UNSPECIFIED);
388
389         switch (state) {
390         case NETDEV_REGISTER:
391                 mutex_lock(&rdev->devlist_mtx);
392                 list_add(&dev->ieee80211_ptr->list, &rdev->netdev_list);
393                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
394                                       "phy80211")) {
395                         printk(KERN_ERR "wireless: failed to add phy80211 "
396                                 "symlink to netdev!\n");
397                 }
398                 dev->ieee80211_ptr->netdev = dev;
399                 mutex_unlock(&rdev->devlist_mtx);
400                 break;
401         case NETDEV_UNREGISTER:
402                 mutex_lock(&rdev->devlist_mtx);
403                 if (!list_empty(&dev->ieee80211_ptr->list)) {
404                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
405                         list_del_init(&dev->ieee80211_ptr->list);
406                 }
407                 mutex_unlock(&rdev->devlist_mtx);
408                 break;
409         }
410
411         return 0;
412 }
413
414 static struct notifier_block cfg80211_netdev_notifier = {
415         .notifier_call = cfg80211_netdev_notifier_call,
416 };
417
418 static int cfg80211_init(void)
419 {
420         int err;
421
422         err = wiphy_sysfs_init();
423         if (err)
424                 goto out_fail_sysfs;
425
426         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
427         if (err)
428                 goto out_fail_notifier;
429
430         err = nl80211_init();
431         if (err)
432                 goto out_fail_nl80211;
433
434         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
435
436         err = regulatory_init();
437         if (err)
438                 goto out_fail_reg;
439
440         return 0;
441
442 out_fail_reg:
443         debugfs_remove(ieee80211_debugfs_dir);
444 out_fail_nl80211:
445         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
446 out_fail_notifier:
447         wiphy_sysfs_exit();
448 out_fail_sysfs:
449         return err;
450 }
451
452 subsys_initcall(cfg80211_init);
453
454 static void cfg80211_exit(void)
455 {
456         debugfs_remove(ieee80211_debugfs_dir);
457         nl80211_exit();
458         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
459         wiphy_sysfs_exit();
460         regulatory_exit();
461 }
462 module_exit(cfg80211_exit);