xref: /openbmc/linux/net/wireless/core.c (revision acc6a093)
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010		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/etherdevice.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/sched.h>
18 #include <net/genetlink.h>
19 #include <net/cfg80211.h>
20 #include "nl80211.h"
21 #include "core.h"
22 #include "sysfs.h"
23 #include "debugfs.h"
24 #include "wext-compat.h"
25 #include "ethtool.h"
26 
27 /* name for sysfs, %d is appended */
28 #define PHY_NAME "phy"
29 
30 MODULE_AUTHOR("Johannes Berg");
31 MODULE_LICENSE("GPL");
32 MODULE_DESCRIPTION("wireless configuration support");
33 
34 /* RCU-protected (and cfg80211_mutex for writers) */
35 LIST_HEAD(cfg80211_rdev_list);
36 int cfg80211_rdev_list_generation;
37 
38 DEFINE_MUTEX(cfg80211_mutex);
39 
40 /* for debugfs */
41 static struct dentry *ieee80211_debugfs_dir;
42 
43 /* for the cleanup, scan and event works */
44 struct workqueue_struct *cfg80211_wq;
45 
46 /* requires cfg80211_mutex to be held! */
47 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
48 {
49 	struct cfg80211_registered_device *result = NULL, *rdev;
50 
51 	if (!wiphy_idx_valid(wiphy_idx))
52 		return NULL;
53 
54 	assert_cfg80211_lock();
55 
56 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
57 		if (rdev->wiphy_idx == wiphy_idx) {
58 			result = rdev;
59 			break;
60 		}
61 	}
62 
63 	return result;
64 }
65 
66 int get_wiphy_idx(struct wiphy *wiphy)
67 {
68 	struct cfg80211_registered_device *rdev;
69 	if (!wiphy)
70 		return WIPHY_IDX_STALE;
71 	rdev = wiphy_to_dev(wiphy);
72 	return rdev->wiphy_idx;
73 }
74 
75 /* requires cfg80211_rdev_mutex to be held! */
76 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
77 {
78 	struct cfg80211_registered_device *rdev;
79 
80 	if (!wiphy_idx_valid(wiphy_idx))
81 		return NULL;
82 
83 	assert_cfg80211_lock();
84 
85 	rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
86 	if (!rdev)
87 		return NULL;
88 	return &rdev->wiphy;
89 }
90 
91 /* requires cfg80211_mutex to be held! */
92 struct cfg80211_registered_device *
93 __cfg80211_rdev_from_info(struct genl_info *info)
94 {
95 	int ifindex;
96 	struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
97 	struct net_device *dev;
98 	int err = -EINVAL;
99 
100 	assert_cfg80211_lock();
101 
102 	if (info->attrs[NL80211_ATTR_WIPHY]) {
103 		bywiphyidx = cfg80211_rdev_by_wiphy_idx(
104 				nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
105 		err = -ENODEV;
106 	}
107 
108 	if (info->attrs[NL80211_ATTR_IFINDEX]) {
109 		ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
110 		dev = dev_get_by_index(genl_info_net(info), ifindex);
111 		if (dev) {
112 			if (dev->ieee80211_ptr)
113 				byifidx =
114 					wiphy_to_dev(dev->ieee80211_ptr->wiphy);
115 			dev_put(dev);
116 		}
117 		err = -ENODEV;
118 	}
119 
120 	if (bywiphyidx && byifidx) {
121 		if (bywiphyidx != byifidx)
122 			return ERR_PTR(-EINVAL);
123 		else
124 			return bywiphyidx; /* == byifidx */
125 	}
126 	if (bywiphyidx)
127 		return bywiphyidx;
128 
129 	if (byifidx)
130 		return byifidx;
131 
132 	return ERR_PTR(err);
133 }
134 
135 struct cfg80211_registered_device *
136 cfg80211_get_dev_from_info(struct genl_info *info)
137 {
138 	struct cfg80211_registered_device *rdev;
139 
140 	mutex_lock(&cfg80211_mutex);
141 	rdev = __cfg80211_rdev_from_info(info);
142 
143 	/* if it is not an error we grab the lock on
144 	 * it to assure it won't be going away while
145 	 * we operate on it */
146 	if (!IS_ERR(rdev))
147 		mutex_lock(&rdev->mtx);
148 
149 	mutex_unlock(&cfg80211_mutex);
150 
151 	return rdev;
152 }
153 
154 struct cfg80211_registered_device *
155 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
156 {
157 	struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
158 	struct net_device *dev;
159 
160 	mutex_lock(&cfg80211_mutex);
161 	dev = dev_get_by_index(net, ifindex);
162 	if (!dev)
163 		goto out;
164 	if (dev->ieee80211_ptr) {
165 		rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
166 		mutex_lock(&rdev->mtx);
167 	} else
168 		rdev = ERR_PTR(-ENODEV);
169 	dev_put(dev);
170  out:
171 	mutex_unlock(&cfg80211_mutex);
172 	return rdev;
173 }
174 
175 /* requires cfg80211_mutex to be held */
176 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
177 			char *newname)
178 {
179 	struct cfg80211_registered_device *rdev2;
180 	int wiphy_idx, taken = -1, result, digits;
181 
182 	assert_cfg80211_lock();
183 
184 	/* prohibit calling the thing phy%d when %d is not its number */
185 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
186 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
187 		/* count number of places needed to print wiphy_idx */
188 		digits = 1;
189 		while (wiphy_idx /= 10)
190 			digits++;
191 		/*
192 		 * deny the name if it is phy<idx> where <idx> is printed
193 		 * without leading zeroes. taken == strlen(newname) here
194 		 */
195 		if (taken == strlen(PHY_NAME) + digits)
196 			return -EINVAL;
197 	}
198 
199 
200 	/* Ignore nop renames */
201 	if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
202 		return 0;
203 
204 	/* Ensure another device does not already have this name. */
205 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
206 		if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
207 			return -EINVAL;
208 
209 	result = device_rename(&rdev->wiphy.dev, newname);
210 	if (result)
211 		return result;
212 
213 	if (rdev->wiphy.debugfsdir &&
214 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
215 			    rdev->wiphy.debugfsdir,
216 			    rdev->wiphy.debugfsdir->d_parent,
217 			    newname))
218 		printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
219 		       newname);
220 
221 	nl80211_notify_dev_rename(rdev);
222 
223 	return 0;
224 }
225 
226 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
227 			  struct net *net)
228 {
229 	struct wireless_dev *wdev;
230 	int err = 0;
231 
232 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
233 		return -EOPNOTSUPP;
234 
235 	list_for_each_entry(wdev, &rdev->netdev_list, list) {
236 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
237 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
238 		if (err)
239 			break;
240 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
241 	}
242 
243 	if (err) {
244 		/* failed -- clean up to old netns */
245 		net = wiphy_net(&rdev->wiphy);
246 
247 		list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,
248 						     list) {
249 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
250 			err = dev_change_net_namespace(wdev->netdev, net,
251 							"wlan%d");
252 			WARN_ON(err);
253 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
254 		}
255 	}
256 
257 	wiphy_net_set(&rdev->wiphy, net);
258 
259 	return err;
260 }
261 
262 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
263 {
264 	struct cfg80211_registered_device *rdev = data;
265 
266 	rdev->ops->rfkill_poll(&rdev->wiphy);
267 }
268 
269 static int cfg80211_rfkill_set_block(void *data, bool blocked)
270 {
271 	struct cfg80211_registered_device *rdev = data;
272 	struct wireless_dev *wdev;
273 
274 	if (!blocked)
275 		return 0;
276 
277 	rtnl_lock();
278 	mutex_lock(&rdev->devlist_mtx);
279 
280 	list_for_each_entry(wdev, &rdev->netdev_list, list)
281 		dev_close(wdev->netdev);
282 
283 	mutex_unlock(&rdev->devlist_mtx);
284 	rtnl_unlock();
285 
286 	return 0;
287 }
288 
289 static void cfg80211_rfkill_sync_work(struct work_struct *work)
290 {
291 	struct cfg80211_registered_device *rdev;
292 
293 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
294 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
295 }
296 
297 static void cfg80211_event_work(struct work_struct *work)
298 {
299 	struct cfg80211_registered_device *rdev;
300 
301 	rdev = container_of(work, struct cfg80211_registered_device,
302 			    event_work);
303 
304 	rtnl_lock();
305 	cfg80211_lock_rdev(rdev);
306 
307 	cfg80211_process_rdev_events(rdev);
308 	cfg80211_unlock_rdev(rdev);
309 	rtnl_unlock();
310 }
311 
312 /* exported functions */
313 
314 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
315 {
316 	static int wiphy_counter;
317 
318 	struct cfg80211_registered_device *rdev;
319 	int alloc_size;
320 
321 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
322 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
323 	WARN_ON(ops->connect && !ops->disconnect);
324 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
325 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
326 	WARN_ON(ops->add_station && !ops->del_station);
327 	WARN_ON(ops->add_mpath && !ops->del_mpath);
328 
329 	alloc_size = sizeof(*rdev) + sizeof_priv;
330 
331 	rdev = kzalloc(alloc_size, GFP_KERNEL);
332 	if (!rdev)
333 		return NULL;
334 
335 	rdev->ops = ops;
336 
337 	mutex_lock(&cfg80211_mutex);
338 
339 	rdev->wiphy_idx = wiphy_counter++;
340 
341 	if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
342 		wiphy_counter--;
343 		mutex_unlock(&cfg80211_mutex);
344 		/* ugh, wrapped! */
345 		kfree(rdev);
346 		return NULL;
347 	}
348 
349 	mutex_unlock(&cfg80211_mutex);
350 
351 	/* give it a proper name */
352 	dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
353 
354 	mutex_init(&rdev->mtx);
355 	mutex_init(&rdev->devlist_mtx);
356 	INIT_LIST_HEAD(&rdev->netdev_list);
357 	spin_lock_init(&rdev->bss_lock);
358 	INIT_LIST_HEAD(&rdev->bss_list);
359 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
360 
361 #ifdef CONFIG_CFG80211_WEXT
362 	rdev->wiphy.wext = &cfg80211_wext_handler;
363 #endif
364 
365 	device_initialize(&rdev->wiphy.dev);
366 	rdev->wiphy.dev.class = &ieee80211_class;
367 	rdev->wiphy.dev.platform_data = rdev;
368 
369 #ifdef CONFIG_CFG80211_DEFAULT_PS
370 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
371 #endif
372 
373 	wiphy_net_set(&rdev->wiphy, &init_net);
374 
375 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
376 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
377 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
378 				   &rdev->rfkill_ops, rdev);
379 
380 	if (!rdev->rfkill) {
381 		kfree(rdev);
382 		return NULL;
383 	}
384 
385 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
386 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
387 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
388 
389 	init_waitqueue_head(&rdev->dev_wait);
390 
391 	/*
392 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
393 	 * Fragmentation and RTS threshold are disabled by default with the
394 	 * special -1 value.
395 	 */
396 	rdev->wiphy.retry_short = 7;
397 	rdev->wiphy.retry_long = 4;
398 	rdev->wiphy.frag_threshold = (u32) -1;
399 	rdev->wiphy.rts_threshold = (u32) -1;
400 	rdev->wiphy.coverage_class = 0;
401 
402 	return &rdev->wiphy;
403 }
404 EXPORT_SYMBOL(wiphy_new);
405 
406 int wiphy_register(struct wiphy *wiphy)
407 {
408 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
409 	int res;
410 	enum ieee80211_band band;
411 	struct ieee80211_supported_band *sband;
412 	bool have_band = false;
413 	int i;
414 	u16 ifmodes = wiphy->interface_modes;
415 
416 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
417 		return -EINVAL;
418 
419 	if (WARN_ON(wiphy->addresses &&
420 		    !is_zero_ether_addr(wiphy->perm_addr) &&
421 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
422 			   ETH_ALEN)))
423 		return -EINVAL;
424 
425 	if (wiphy->addresses)
426 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
427 
428 	/* sanity check ifmodes */
429 	WARN_ON(!ifmodes);
430 	ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
431 	if (WARN_ON(ifmodes != wiphy->interface_modes))
432 		wiphy->interface_modes = ifmodes;
433 
434 	/* sanity check supported bands/channels */
435 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
436 		sband = wiphy->bands[band];
437 		if (!sband)
438 			continue;
439 
440 		sband->band = band;
441 
442 		if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
443 			return -EINVAL;
444 
445 		/*
446 		 * Since we use a u32 for rate bitmaps in
447 		 * ieee80211_get_response_rate, we cannot
448 		 * have more than 32 legacy rates.
449 		 */
450 		if (WARN_ON(sband->n_bitrates > 32))
451 			return -EINVAL;
452 
453 		for (i = 0; i < sband->n_channels; i++) {
454 			sband->channels[i].orig_flags =
455 				sband->channels[i].flags;
456 			sband->channels[i].orig_mag =
457 				sband->channels[i].max_antenna_gain;
458 			sband->channels[i].orig_mpwr =
459 				sband->channels[i].max_power;
460 			sband->channels[i].band = band;
461 		}
462 
463 		have_band = true;
464 	}
465 
466 	if (!have_band) {
467 		WARN_ON(1);
468 		return -EINVAL;
469 	}
470 
471 	/* check and set up bitrates */
472 	ieee80211_set_bitrate_flags(wiphy);
473 
474 	res = device_add(&rdev->wiphy.dev);
475 	if (res)
476 		return res;
477 
478 	res = rfkill_register(rdev->rfkill);
479 	if (res)
480 		goto out_rm_dev;
481 
482 	mutex_lock(&cfg80211_mutex);
483 
484 	/* set up regulatory info */
485 	wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
486 
487 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
488 	cfg80211_rdev_list_generation++;
489 
490 	mutex_unlock(&cfg80211_mutex);
491 
492 	/* add to debugfs */
493 	rdev->wiphy.debugfsdir =
494 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
495 				   ieee80211_debugfs_dir);
496 	if (IS_ERR(rdev->wiphy.debugfsdir))
497 		rdev->wiphy.debugfsdir = NULL;
498 
499 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
500 		struct regulatory_request request;
501 
502 		request.wiphy_idx = get_wiphy_idx(wiphy);
503 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
504 		request.alpha2[0] = '9';
505 		request.alpha2[1] = '9';
506 
507 		nl80211_send_reg_change_event(&request);
508 	}
509 
510 	cfg80211_debugfs_rdev_add(rdev);
511 
512 	return 0;
513 
514  out_rm_dev:
515 	device_del(&rdev->wiphy.dev);
516 	return res;
517 }
518 EXPORT_SYMBOL(wiphy_register);
519 
520 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
521 {
522 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
523 
524 	if (!rdev->ops->rfkill_poll)
525 		return;
526 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
527 	rfkill_resume_polling(rdev->rfkill);
528 }
529 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
530 
531 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
532 {
533 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
534 
535 	rfkill_pause_polling(rdev->rfkill);
536 }
537 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
538 
539 void wiphy_unregister(struct wiphy *wiphy)
540 {
541 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
542 
543 	rfkill_unregister(rdev->rfkill);
544 
545 	/* protect the device list */
546 	mutex_lock(&cfg80211_mutex);
547 
548 	wait_event(rdev->dev_wait, ({
549 		int __count;
550 		mutex_lock(&rdev->devlist_mtx);
551 		__count = rdev->opencount;
552 		mutex_unlock(&rdev->devlist_mtx);
553 		__count == 0;}));
554 
555 	mutex_lock(&rdev->devlist_mtx);
556 	BUG_ON(!list_empty(&rdev->netdev_list));
557 	mutex_unlock(&rdev->devlist_mtx);
558 
559 	/*
560 	 * First remove the hardware from everywhere, this makes
561 	 * it impossible to find from userspace.
562 	 */
563 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
564 	list_del_rcu(&rdev->list);
565 	synchronize_rcu();
566 
567 	/*
568 	 * Try to grab rdev->mtx. If a command is still in progress,
569 	 * hopefully the driver will refuse it since it's tearing
570 	 * down the device already. We wait for this command to complete
571 	 * before unlinking the item from the list.
572 	 * Note: as codified by the BUG_ON above we cannot get here if
573 	 * a virtual interface is still present. Hence, we can only get
574 	 * to lock contention here if userspace issues a command that
575 	 * identified the hardware by wiphy index.
576 	 */
577 	cfg80211_lock_rdev(rdev);
578 	/* nothing */
579 	cfg80211_unlock_rdev(rdev);
580 
581 	/* If this device got a regulatory hint tell core its
582 	 * free to listen now to a new shiny device regulatory hint */
583 	reg_device_remove(wiphy);
584 
585 	cfg80211_rdev_list_generation++;
586 	device_del(&rdev->wiphy.dev);
587 
588 	mutex_unlock(&cfg80211_mutex);
589 
590 	flush_work(&rdev->scan_done_wk);
591 	cancel_work_sync(&rdev->conn_work);
592 	flush_work(&rdev->event_work);
593 }
594 EXPORT_SYMBOL(wiphy_unregister);
595 
596 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
597 {
598 	struct cfg80211_internal_bss *scan, *tmp;
599 	rfkill_destroy(rdev->rfkill);
600 	mutex_destroy(&rdev->mtx);
601 	mutex_destroy(&rdev->devlist_mtx);
602 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
603 		cfg80211_put_bss(&scan->pub);
604 	kfree(rdev);
605 }
606 
607 void wiphy_free(struct wiphy *wiphy)
608 {
609 	put_device(&wiphy->dev);
610 }
611 EXPORT_SYMBOL(wiphy_free);
612 
613 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
614 {
615 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
616 
617 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
618 		schedule_work(&rdev->rfkill_sync);
619 }
620 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
621 
622 static void wdev_cleanup_work(struct work_struct *work)
623 {
624 	struct wireless_dev *wdev;
625 	struct cfg80211_registered_device *rdev;
626 
627 	wdev = container_of(work, struct wireless_dev, cleanup_work);
628 	rdev = wiphy_to_dev(wdev->wiphy);
629 
630 	cfg80211_lock_rdev(rdev);
631 
632 	if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) {
633 		rdev->scan_req->aborted = true;
634 		___cfg80211_scan_done(rdev, true);
635 	}
636 
637 	cfg80211_unlock_rdev(rdev);
638 
639 	mutex_lock(&rdev->devlist_mtx);
640 	rdev->opencount--;
641 	mutex_unlock(&rdev->devlist_mtx);
642 	wake_up(&rdev->dev_wait);
643 
644 	dev_put(wdev->netdev);
645 }
646 
647 static struct device_type wiphy_type = {
648 	.name	= "wlan",
649 };
650 
651 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
652 					 unsigned long state,
653 					 void *ndev)
654 {
655 	struct net_device *dev = ndev;
656 	struct wireless_dev *wdev = dev->ieee80211_ptr;
657 	struct cfg80211_registered_device *rdev;
658 
659 	if (!wdev)
660 		return NOTIFY_DONE;
661 
662 	rdev = wiphy_to_dev(wdev->wiphy);
663 
664 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
665 
666 	switch (state) {
667 	case NETDEV_POST_INIT:
668 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
669 		break;
670 	case NETDEV_REGISTER:
671 		/*
672 		 * NB: cannot take rdev->mtx here because this may be
673 		 * called within code protected by it when interfaces
674 		 * are added with nl80211.
675 		 */
676 		mutex_init(&wdev->mtx);
677 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
678 		INIT_LIST_HEAD(&wdev->event_list);
679 		spin_lock_init(&wdev->event_lock);
680 		INIT_LIST_HEAD(&wdev->action_registrations);
681 		spin_lock_init(&wdev->action_registrations_lock);
682 
683 		mutex_lock(&rdev->devlist_mtx);
684 		list_add_rcu(&wdev->list, &rdev->netdev_list);
685 		rdev->devlist_generation++;
686 		/* can only change netns with wiphy */
687 		dev->features |= NETIF_F_NETNS_LOCAL;
688 
689 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
690 				      "phy80211")) {
691 			printk(KERN_ERR "wireless: failed to add phy80211 "
692 				"symlink to netdev!\n");
693 		}
694 		wdev->netdev = dev;
695 		wdev->sme_state = CFG80211_SME_IDLE;
696 		mutex_unlock(&rdev->devlist_mtx);
697 #ifdef CONFIG_CFG80211_WEXT
698 		wdev->wext.default_key = -1;
699 		wdev->wext.default_mgmt_key = -1;
700 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
701 #endif
702 
703 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
704 			wdev->ps = true;
705 		else
706 			wdev->ps = false;
707 		wdev->ps_timeout = 100;
708 		if (rdev->ops->set_power_mgmt)
709 			if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
710 						      wdev->ps,
711 						      wdev->ps_timeout)) {
712 				/* assume this means it's off */
713 				wdev->ps = false;
714 			}
715 
716 		if (!dev->ethtool_ops)
717 			dev->ethtool_ops = &cfg80211_ethtool_ops;
718 
719 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
720 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
721 			dev->priv_flags |= IFF_DONT_BRIDGE;
722 		break;
723 	case NETDEV_GOING_DOWN:
724 		switch (wdev->iftype) {
725 		case NL80211_IFTYPE_ADHOC:
726 			cfg80211_leave_ibss(rdev, dev, true);
727 			break;
728 		case NL80211_IFTYPE_STATION:
729 			wdev_lock(wdev);
730 #ifdef CONFIG_CFG80211_WEXT
731 			kfree(wdev->wext.ie);
732 			wdev->wext.ie = NULL;
733 			wdev->wext.ie_len = 0;
734 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
735 #endif
736 			__cfg80211_disconnect(rdev, dev,
737 					      WLAN_REASON_DEAUTH_LEAVING, true);
738 			cfg80211_mlme_down(rdev, dev);
739 			wdev_unlock(wdev);
740 			break;
741 		default:
742 			break;
743 		}
744 		break;
745 	case NETDEV_DOWN:
746 		dev_hold(dev);
747 		queue_work(cfg80211_wq, &wdev->cleanup_work);
748 		break;
749 	case NETDEV_UP:
750 		/*
751 		 * If we have a really quick DOWN/UP succession we may
752 		 * have this work still pending ... cancel it and see
753 		 * if it was pending, in which case we need to account
754 		 * for some of the work it would have done.
755 		 */
756 		if (cancel_work_sync(&wdev->cleanup_work)) {
757 			mutex_lock(&rdev->devlist_mtx);
758 			rdev->opencount--;
759 			mutex_unlock(&rdev->devlist_mtx);
760 			dev_put(dev);
761 		}
762 		cfg80211_lock_rdev(rdev);
763 		mutex_lock(&rdev->devlist_mtx);
764 #ifdef CONFIG_CFG80211_WEXT
765 		wdev_lock(wdev);
766 		switch (wdev->iftype) {
767 		case NL80211_IFTYPE_ADHOC:
768 			cfg80211_ibss_wext_join(rdev, wdev);
769 			break;
770 		case NL80211_IFTYPE_STATION:
771 			cfg80211_mgd_wext_connect(rdev, wdev);
772 			break;
773 		default:
774 			break;
775 		}
776 		wdev_unlock(wdev);
777 #endif
778 		rdev->opencount++;
779 		mutex_unlock(&rdev->devlist_mtx);
780 		cfg80211_unlock_rdev(rdev);
781 		break;
782 	case NETDEV_UNREGISTER:
783 		/*
784 		 * NB: cannot take rdev->mtx here because this may be
785 		 * called within code protected by it when interfaces
786 		 * are removed with nl80211.
787 		 */
788 		mutex_lock(&rdev->devlist_mtx);
789 		/*
790 		 * It is possible to get NETDEV_UNREGISTER
791 		 * multiple times. To detect that, check
792 		 * that the interface is still on the list
793 		 * of registered interfaces, and only then
794 		 * remove and clean it up.
795 		 */
796 		if (!list_empty(&wdev->list)) {
797 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
798 			list_del_rcu(&wdev->list);
799 			rdev->devlist_generation++;
800 			cfg80211_mlme_purge_actions(wdev);
801 #ifdef CONFIG_CFG80211_WEXT
802 			kfree(wdev->wext.keys);
803 #endif
804 		}
805 		mutex_unlock(&rdev->devlist_mtx);
806 		/*
807 		 * synchronise (so that we won't find this netdev
808 		 * from other code any more) and then clear the list
809 		 * head so that the above code can safely check for
810 		 * !list_empty() to avoid double-cleanup.
811 		 */
812 		synchronize_rcu();
813 		INIT_LIST_HEAD(&wdev->list);
814 		break;
815 	case NETDEV_PRE_UP:
816 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
817 			return notifier_from_errno(-EOPNOTSUPP);
818 		if (rfkill_blocked(rdev->rfkill))
819 			return notifier_from_errno(-ERFKILL);
820 		break;
821 	}
822 
823 	return NOTIFY_DONE;
824 }
825 
826 static struct notifier_block cfg80211_netdev_notifier = {
827 	.notifier_call = cfg80211_netdev_notifier_call,
828 };
829 
830 static void __net_exit cfg80211_pernet_exit(struct net *net)
831 {
832 	struct cfg80211_registered_device *rdev;
833 
834 	rtnl_lock();
835 	mutex_lock(&cfg80211_mutex);
836 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
837 		if (net_eq(wiphy_net(&rdev->wiphy), net))
838 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
839 	}
840 	mutex_unlock(&cfg80211_mutex);
841 	rtnl_unlock();
842 }
843 
844 static struct pernet_operations cfg80211_pernet_ops = {
845 	.exit = cfg80211_pernet_exit,
846 };
847 
848 static int __init cfg80211_init(void)
849 {
850 	int err;
851 
852 	err = register_pernet_device(&cfg80211_pernet_ops);
853 	if (err)
854 		goto out_fail_pernet;
855 
856 	err = wiphy_sysfs_init();
857 	if (err)
858 		goto out_fail_sysfs;
859 
860 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
861 	if (err)
862 		goto out_fail_notifier;
863 
864 	err = nl80211_init();
865 	if (err)
866 		goto out_fail_nl80211;
867 
868 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
869 
870 	err = regulatory_init();
871 	if (err)
872 		goto out_fail_reg;
873 
874 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
875 	if (!cfg80211_wq)
876 		goto out_fail_wq;
877 
878 	return 0;
879 
880 out_fail_wq:
881 	regulatory_exit();
882 out_fail_reg:
883 	debugfs_remove(ieee80211_debugfs_dir);
884 out_fail_nl80211:
885 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
886 out_fail_notifier:
887 	wiphy_sysfs_exit();
888 out_fail_sysfs:
889 	unregister_pernet_device(&cfg80211_pernet_ops);
890 out_fail_pernet:
891 	return err;
892 }
893 subsys_initcall(cfg80211_init);
894 
895 static void cfg80211_exit(void)
896 {
897 	debugfs_remove(ieee80211_debugfs_dir);
898 	nl80211_exit();
899 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
900 	wiphy_sysfs_exit();
901 	regulatory_exit();
902 	unregister_pernet_device(&cfg80211_pernet_ops);
903 	destroy_workqueue(cfg80211_wq);
904 }
905 module_exit(cfg80211_exit);
906