xref: /linux/net/wireless/core.c (revision f49f4ab95c301dbccad0efe85296d908b8ae7ad4)
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010		Johannes Berg <johannes@sipsolutions.net>
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/if.h>
10 #include <linux/module.h>
11 #include <linux/err.h>
12 #include <linux/list.h>
13 #include <linux/slab.h>
14 #include <linux/nl80211.h>
15 #include <linux/debugfs.h>
16 #include <linux/notifier.h>
17 #include <linux/device.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/sched.h>
21 #include <net/genetlink.h>
22 #include <net/cfg80211.h>
23 #include "nl80211.h"
24 #include "core.h"
25 #include "sysfs.h"
26 #include "debugfs.h"
27 #include "wext-compat.h"
28 #include "ethtool.h"
29 
30 /* name for sysfs, %d is appended */
31 #define PHY_NAME "phy"
32 
33 MODULE_AUTHOR("Johannes Berg");
34 MODULE_LICENSE("GPL");
35 MODULE_DESCRIPTION("wireless configuration support");
36 
37 /* RCU-protected (and cfg80211_mutex for writers) */
38 LIST_HEAD(cfg80211_rdev_list);
39 int cfg80211_rdev_list_generation;
40 
41 DEFINE_MUTEX(cfg80211_mutex);
42 
43 /* for debugfs */
44 static struct dentry *ieee80211_debugfs_dir;
45 
46 /* for the cleanup, scan and event works */
47 struct workqueue_struct *cfg80211_wq;
48 
49 static bool cfg80211_disable_40mhz_24ghz;
50 module_param(cfg80211_disable_40mhz_24ghz, bool, 0644);
51 MODULE_PARM_DESC(cfg80211_disable_40mhz_24ghz,
52 		 "Disable 40MHz support in the 2.4GHz band");
53 
54 /* requires cfg80211_mutex to be held! */
55 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
56 {
57 	struct cfg80211_registered_device *result = NULL, *rdev;
58 
59 	if (!wiphy_idx_valid(wiphy_idx))
60 		return NULL;
61 
62 	assert_cfg80211_lock();
63 
64 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
65 		if (rdev->wiphy_idx == wiphy_idx) {
66 			result = rdev;
67 			break;
68 		}
69 	}
70 
71 	return result;
72 }
73 
74 int get_wiphy_idx(struct wiphy *wiphy)
75 {
76 	struct cfg80211_registered_device *rdev;
77 	if (!wiphy)
78 		return WIPHY_IDX_STALE;
79 	rdev = wiphy_to_dev(wiphy);
80 	return rdev->wiphy_idx;
81 }
82 
83 /* requires cfg80211_rdev_mutex to be held! */
84 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
85 {
86 	struct cfg80211_registered_device *rdev;
87 
88 	if (!wiphy_idx_valid(wiphy_idx))
89 		return NULL;
90 
91 	assert_cfg80211_lock();
92 
93 	rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
94 	if (!rdev)
95 		return NULL;
96 	return &rdev->wiphy;
97 }
98 
99 struct cfg80211_registered_device *
100 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
101 {
102 	struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
103 	struct net_device *dev;
104 
105 	mutex_lock(&cfg80211_mutex);
106 	dev = dev_get_by_index(net, ifindex);
107 	if (!dev)
108 		goto out;
109 	if (dev->ieee80211_ptr) {
110 		rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
111 		mutex_lock(&rdev->mtx);
112 	} else
113 		rdev = ERR_PTR(-ENODEV);
114 	dev_put(dev);
115  out:
116 	mutex_unlock(&cfg80211_mutex);
117 	return rdev;
118 }
119 
120 /* requires cfg80211_mutex to be held */
121 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
122 			char *newname)
123 {
124 	struct cfg80211_registered_device *rdev2;
125 	int wiphy_idx, taken = -1, result, digits;
126 
127 	assert_cfg80211_lock();
128 
129 	/* prohibit calling the thing phy%d when %d is not its number */
130 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
131 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
132 		/* count number of places needed to print wiphy_idx */
133 		digits = 1;
134 		while (wiphy_idx /= 10)
135 			digits++;
136 		/*
137 		 * deny the name if it is phy<idx> where <idx> is printed
138 		 * without leading zeroes. taken == strlen(newname) here
139 		 */
140 		if (taken == strlen(PHY_NAME) + digits)
141 			return -EINVAL;
142 	}
143 
144 
145 	/* Ignore nop renames */
146 	if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
147 		return 0;
148 
149 	/* Ensure another device does not already have this name. */
150 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
151 		if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
152 			return -EINVAL;
153 
154 	result = device_rename(&rdev->wiphy.dev, newname);
155 	if (result)
156 		return result;
157 
158 	if (rdev->wiphy.debugfsdir &&
159 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
160 			    rdev->wiphy.debugfsdir,
161 			    rdev->wiphy.debugfsdir->d_parent,
162 			    newname))
163 		pr_err("failed to rename debugfs dir to %s!\n", newname);
164 
165 	nl80211_notify_dev_rename(rdev);
166 
167 	return 0;
168 }
169 
170 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
171 			  struct net *net)
172 {
173 	struct wireless_dev *wdev;
174 	int err = 0;
175 
176 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
177 		return -EOPNOTSUPP;
178 
179 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
180 		if (!wdev->netdev)
181 			continue;
182 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
183 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
184 		if (err)
185 			break;
186 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
187 	}
188 
189 	if (err) {
190 		/* failed -- clean up to old netns */
191 		net = wiphy_net(&rdev->wiphy);
192 
193 		list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,
194 						     list) {
195 			if (!wdev->netdev)
196 				continue;
197 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
198 			err = dev_change_net_namespace(wdev->netdev, net,
199 							"wlan%d");
200 			WARN_ON(err);
201 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
202 		}
203 
204 		return err;
205 	}
206 
207 	wiphy_net_set(&rdev->wiphy, net);
208 
209 	err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
210 	WARN_ON(err);
211 
212 	return 0;
213 }
214 
215 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
216 {
217 	struct cfg80211_registered_device *rdev = data;
218 
219 	rdev->ops->rfkill_poll(&rdev->wiphy);
220 }
221 
222 static int cfg80211_rfkill_set_block(void *data, bool blocked)
223 {
224 	struct cfg80211_registered_device *rdev = data;
225 	struct wireless_dev *wdev;
226 
227 	if (!blocked)
228 		return 0;
229 
230 	rtnl_lock();
231 	mutex_lock(&rdev->devlist_mtx);
232 
233 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
234 		if (wdev->netdev) {
235 			dev_close(wdev->netdev);
236 			continue;
237 		}
238 		/* otherwise, check iftype */
239 		switch (wdev->iftype) {
240 		case NL80211_IFTYPE_P2P_DEVICE:
241 			if (!wdev->p2p_started)
242 				break;
243 			rdev->ops->stop_p2p_device(&rdev->wiphy, wdev);
244 			wdev->p2p_started = false;
245 			rdev->opencount--;
246 			break;
247 		default:
248 			break;
249 		}
250 	}
251 
252 	mutex_unlock(&rdev->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 *rdev;
261 
262 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
263 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
264 }
265 
266 static void cfg80211_event_work(struct work_struct *work)
267 {
268 	struct cfg80211_registered_device *rdev;
269 
270 	rdev = container_of(work, struct cfg80211_registered_device,
271 			    event_work);
272 
273 	rtnl_lock();
274 	cfg80211_lock_rdev(rdev);
275 
276 	cfg80211_process_rdev_events(rdev);
277 	cfg80211_unlock_rdev(rdev);
278 	rtnl_unlock();
279 }
280 
281 /* exported functions */
282 
283 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
284 {
285 	static int wiphy_counter;
286 
287 	struct cfg80211_registered_device *rdev;
288 	int alloc_size;
289 
290 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
291 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
292 	WARN_ON(ops->connect && !ops->disconnect);
293 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
294 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
295 	WARN_ON(ops->add_station && !ops->del_station);
296 	WARN_ON(ops->add_mpath && !ops->del_mpath);
297 	WARN_ON(ops->join_mesh && !ops->leave_mesh);
298 
299 	alloc_size = sizeof(*rdev) + sizeof_priv;
300 
301 	rdev = kzalloc(alloc_size, GFP_KERNEL);
302 	if (!rdev)
303 		return NULL;
304 
305 	rdev->ops = ops;
306 
307 	mutex_lock(&cfg80211_mutex);
308 
309 	rdev->wiphy_idx = wiphy_counter++;
310 
311 	if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
312 		wiphy_counter--;
313 		mutex_unlock(&cfg80211_mutex);
314 		/* ugh, wrapped! */
315 		kfree(rdev);
316 		return NULL;
317 	}
318 
319 	mutex_unlock(&cfg80211_mutex);
320 
321 	/* give it a proper name */
322 	dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
323 
324 	mutex_init(&rdev->mtx);
325 	mutex_init(&rdev->devlist_mtx);
326 	mutex_init(&rdev->sched_scan_mtx);
327 	INIT_LIST_HEAD(&rdev->wdev_list);
328 	spin_lock_init(&rdev->bss_lock);
329 	INIT_LIST_HEAD(&rdev->bss_list);
330 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
331 	INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
332 #ifdef CONFIG_CFG80211_WEXT
333 	rdev->wiphy.wext = &cfg80211_wext_handler;
334 #endif
335 
336 	device_initialize(&rdev->wiphy.dev);
337 	rdev->wiphy.dev.class = &ieee80211_class;
338 	rdev->wiphy.dev.platform_data = rdev;
339 
340 #ifdef CONFIG_CFG80211_DEFAULT_PS
341 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
342 #endif
343 
344 	wiphy_net_set(&rdev->wiphy, &init_net);
345 
346 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
347 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
348 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
349 				   &rdev->rfkill_ops, rdev);
350 
351 	if (!rdev->rfkill) {
352 		kfree(rdev);
353 		return NULL;
354 	}
355 
356 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
357 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
358 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
359 
360 	init_waitqueue_head(&rdev->dev_wait);
361 
362 	/*
363 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
364 	 * Fragmentation and RTS threshold are disabled by default with the
365 	 * special -1 value.
366 	 */
367 	rdev->wiphy.retry_short = 7;
368 	rdev->wiphy.retry_long = 4;
369 	rdev->wiphy.frag_threshold = (u32) -1;
370 	rdev->wiphy.rts_threshold = (u32) -1;
371 	rdev->wiphy.coverage_class = 0;
372 
373 	return &rdev->wiphy;
374 }
375 EXPORT_SYMBOL(wiphy_new);
376 
377 static int wiphy_verify_combinations(struct wiphy *wiphy)
378 {
379 	const struct ieee80211_iface_combination *c;
380 	int i, j;
381 
382 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
383 		u32 cnt = 0;
384 		u16 all_iftypes = 0;
385 
386 		c = &wiphy->iface_combinations[i];
387 
388 		/* Combinations with just one interface aren't real */
389 		if (WARN_ON(c->max_interfaces < 2))
390 			return -EINVAL;
391 
392 		/* Need at least one channel */
393 		if (WARN_ON(!c->num_different_channels))
394 			return -EINVAL;
395 
396 		/*
397 		 * Put a sane limit on maximum number of different
398 		 * channels to simplify channel accounting code.
399 		 */
400 		if (WARN_ON(c->num_different_channels >
401 				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
402 			return -EINVAL;
403 
404 		if (WARN_ON(!c->n_limits))
405 			return -EINVAL;
406 
407 		for (j = 0; j < c->n_limits; j++) {
408 			u16 types = c->limits[j].types;
409 
410 			/*
411 			 * interface types shouldn't overlap, this is
412 			 * used in cfg80211_can_change_interface()
413 			 */
414 			if (WARN_ON(types & all_iftypes))
415 				return -EINVAL;
416 			all_iftypes |= types;
417 
418 			if (WARN_ON(!c->limits[j].max))
419 				return -EINVAL;
420 
421 			/* Shouldn't list software iftypes in combinations! */
422 			if (WARN_ON(wiphy->software_iftypes & types))
423 				return -EINVAL;
424 
425 			/* Only a single P2P_DEVICE can be allowed */
426 			if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
427 				    c->limits[j].max > 1))
428 				return -EINVAL;
429 
430 			cnt += c->limits[j].max;
431 			/*
432 			 * Don't advertise an unsupported type
433 			 * in a combination.
434 			 */
435 			if (WARN_ON((wiphy->interface_modes & types) != types))
436 				return -EINVAL;
437 		}
438 
439 		/* You can't even choose that many! */
440 		if (WARN_ON(cnt < c->max_interfaces))
441 			return -EINVAL;
442 	}
443 
444 	return 0;
445 }
446 
447 int wiphy_register(struct wiphy *wiphy)
448 {
449 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
450 	int res;
451 	enum ieee80211_band band;
452 	struct ieee80211_supported_band *sband;
453 	bool have_band = false;
454 	int i;
455 	u16 ifmodes = wiphy->interface_modes;
456 
457 #ifdef CONFIG_PM
458 	if (WARN_ON((wiphy->wowlan.flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
459 		    !(wiphy->wowlan.flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
460 		return -EINVAL;
461 #endif
462 
463 	if (WARN_ON(wiphy->ap_sme_capa &&
464 		    !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
465 		return -EINVAL;
466 
467 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
468 		return -EINVAL;
469 
470 	if (WARN_ON(wiphy->addresses &&
471 		    !is_zero_ether_addr(wiphy->perm_addr) &&
472 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
473 			   ETH_ALEN)))
474 		return -EINVAL;
475 
476 	if (wiphy->addresses)
477 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
478 
479 	/* sanity check ifmodes */
480 	WARN_ON(!ifmodes);
481 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
482 	if (WARN_ON(ifmodes != wiphy->interface_modes))
483 		wiphy->interface_modes = ifmodes;
484 
485 	res = wiphy_verify_combinations(wiphy);
486 	if (res)
487 		return res;
488 
489 	/* sanity check supported bands/channels */
490 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
491 		sband = wiphy->bands[band];
492 		if (!sband)
493 			continue;
494 
495 		sband->band = band;
496 		if (WARN_ON(!sband->n_channels))
497 			return -EINVAL;
498 		/*
499 		 * on 60gHz band, there are no legacy rates, so
500 		 * n_bitrates is 0
501 		 */
502 		if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
503 			    !sband->n_bitrates))
504 			return -EINVAL;
505 
506 		/*
507 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
508 		 * modify the sband's ht data even if the driver uses a
509 		 * global structure for that.
510 		 */
511 		if (cfg80211_disable_40mhz_24ghz &&
512 		    band == IEEE80211_BAND_2GHZ &&
513 		    sband->ht_cap.ht_supported) {
514 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
515 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
516 		}
517 
518 		/*
519 		 * Since we use a u32 for rate bitmaps in
520 		 * ieee80211_get_response_rate, we cannot
521 		 * have more than 32 legacy rates.
522 		 */
523 		if (WARN_ON(sband->n_bitrates > 32))
524 			return -EINVAL;
525 
526 		for (i = 0; i < sband->n_channels; i++) {
527 			sband->channels[i].orig_flags =
528 				sband->channels[i].flags;
529 			sband->channels[i].orig_mag =
530 				sband->channels[i].max_antenna_gain;
531 			sband->channels[i].orig_mpwr =
532 				sband->channels[i].max_power;
533 			sband->channels[i].band = band;
534 		}
535 
536 		have_band = true;
537 	}
538 
539 	if (!have_band) {
540 		WARN_ON(1);
541 		return -EINVAL;
542 	}
543 
544 #ifdef CONFIG_PM
545 	if (rdev->wiphy.wowlan.n_patterns) {
546 		if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
547 			    rdev->wiphy.wowlan.pattern_min_len >
548 			    rdev->wiphy.wowlan.pattern_max_len))
549 			return -EINVAL;
550 	}
551 #endif
552 
553 	/* check and set up bitrates */
554 	ieee80211_set_bitrate_flags(wiphy);
555 
556 	mutex_lock(&cfg80211_mutex);
557 
558 	res = device_add(&rdev->wiphy.dev);
559 	if (res) {
560 		mutex_unlock(&cfg80211_mutex);
561 		return res;
562 	}
563 
564 	/* set up regulatory info */
565 	wiphy_regulatory_register(wiphy);
566 
567 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
568 	cfg80211_rdev_list_generation++;
569 
570 	/* add to debugfs */
571 	rdev->wiphy.debugfsdir =
572 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
573 				   ieee80211_debugfs_dir);
574 	if (IS_ERR(rdev->wiphy.debugfsdir))
575 		rdev->wiphy.debugfsdir = NULL;
576 
577 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
578 		struct regulatory_request request;
579 
580 		request.wiphy_idx = get_wiphy_idx(wiphy);
581 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
582 		request.alpha2[0] = '9';
583 		request.alpha2[1] = '9';
584 
585 		nl80211_send_reg_change_event(&request);
586 	}
587 
588 	cfg80211_debugfs_rdev_add(rdev);
589 	mutex_unlock(&cfg80211_mutex);
590 
591 	/*
592 	 * due to a locking dependency this has to be outside of the
593 	 * cfg80211_mutex lock
594 	 */
595 	res = rfkill_register(rdev->rfkill);
596 	if (res)
597 		goto out_rm_dev;
598 
599 	rtnl_lock();
600 	rdev->wiphy.registered = true;
601 	rtnl_unlock();
602 	return 0;
603 
604 out_rm_dev:
605 	device_del(&rdev->wiphy.dev);
606 	return res;
607 }
608 EXPORT_SYMBOL(wiphy_register);
609 
610 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
611 {
612 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
613 
614 	if (!rdev->ops->rfkill_poll)
615 		return;
616 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
617 	rfkill_resume_polling(rdev->rfkill);
618 }
619 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
620 
621 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
622 {
623 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
624 
625 	rfkill_pause_polling(rdev->rfkill);
626 }
627 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
628 
629 void wiphy_unregister(struct wiphy *wiphy)
630 {
631 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
632 
633 	rtnl_lock();
634 	rdev->wiphy.registered = false;
635 	rtnl_unlock();
636 
637 	rfkill_unregister(rdev->rfkill);
638 
639 	/* protect the device list */
640 	mutex_lock(&cfg80211_mutex);
641 
642 	wait_event(rdev->dev_wait, ({
643 		int __count;
644 		mutex_lock(&rdev->devlist_mtx);
645 		__count = rdev->opencount;
646 		mutex_unlock(&rdev->devlist_mtx);
647 		__count == 0; }));
648 
649 	mutex_lock(&rdev->devlist_mtx);
650 	BUG_ON(!list_empty(&rdev->wdev_list));
651 	mutex_unlock(&rdev->devlist_mtx);
652 
653 	/*
654 	 * First remove the hardware from everywhere, this makes
655 	 * it impossible to find from userspace.
656 	 */
657 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
658 	list_del_rcu(&rdev->list);
659 	synchronize_rcu();
660 
661 	/*
662 	 * Try to grab rdev->mtx. If a command is still in progress,
663 	 * hopefully the driver will refuse it since it's tearing
664 	 * down the device already. We wait for this command to complete
665 	 * before unlinking the item from the list.
666 	 * Note: as codified by the BUG_ON above we cannot get here if
667 	 * a virtual interface is still present. Hence, we can only get
668 	 * to lock contention here if userspace issues a command that
669 	 * identified the hardware by wiphy index.
670 	 */
671 	cfg80211_lock_rdev(rdev);
672 	/* nothing */
673 	cfg80211_unlock_rdev(rdev);
674 
675 	/*
676 	 * If this device got a regulatory hint tell core its
677 	 * free to listen now to a new shiny device regulatory hint
678 	 */
679 	wiphy_regulatory_deregister(wiphy);
680 
681 	cfg80211_rdev_list_generation++;
682 	device_del(&rdev->wiphy.dev);
683 
684 	mutex_unlock(&cfg80211_mutex);
685 
686 	flush_work(&rdev->scan_done_wk);
687 	cancel_work_sync(&rdev->conn_work);
688 	flush_work(&rdev->event_work);
689 
690 	if (rdev->wowlan && rdev->ops->set_wakeup)
691 		rdev->ops->set_wakeup(&rdev->wiphy, false);
692 	cfg80211_rdev_free_wowlan(rdev);
693 }
694 EXPORT_SYMBOL(wiphy_unregister);
695 
696 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
697 {
698 	struct cfg80211_internal_bss *scan, *tmp;
699 	rfkill_destroy(rdev->rfkill);
700 	mutex_destroy(&rdev->mtx);
701 	mutex_destroy(&rdev->devlist_mtx);
702 	mutex_destroy(&rdev->sched_scan_mtx);
703 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
704 		cfg80211_put_bss(&scan->pub);
705 	kfree(rdev);
706 }
707 
708 void wiphy_free(struct wiphy *wiphy)
709 {
710 	put_device(&wiphy->dev);
711 }
712 EXPORT_SYMBOL(wiphy_free);
713 
714 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
715 {
716 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
717 
718 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
719 		schedule_work(&rdev->rfkill_sync);
720 }
721 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
722 
723 static void wdev_cleanup_work(struct work_struct *work)
724 {
725 	struct wireless_dev *wdev;
726 	struct cfg80211_registered_device *rdev;
727 
728 	wdev = container_of(work, struct wireless_dev, cleanup_work);
729 	rdev = wiphy_to_dev(wdev->wiphy);
730 
731 	cfg80211_lock_rdev(rdev);
732 
733 	if (WARN_ON(rdev->scan_req && rdev->scan_req->wdev == wdev)) {
734 		rdev->scan_req->aborted = true;
735 		___cfg80211_scan_done(rdev, true);
736 	}
737 
738 	cfg80211_unlock_rdev(rdev);
739 
740 	mutex_lock(&rdev->sched_scan_mtx);
741 
742 	if (WARN_ON(rdev->sched_scan_req &&
743 		    rdev->sched_scan_req->dev == wdev->netdev)) {
744 		__cfg80211_stop_sched_scan(rdev, false);
745 	}
746 
747 	mutex_unlock(&rdev->sched_scan_mtx);
748 
749 	mutex_lock(&rdev->devlist_mtx);
750 	rdev->opencount--;
751 	mutex_unlock(&rdev->devlist_mtx);
752 	wake_up(&rdev->dev_wait);
753 
754 	dev_put(wdev->netdev);
755 }
756 
757 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
758 {
759 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
760 
761 	ASSERT_RTNL();
762 
763 	if (WARN_ON(wdev->netdev))
764 		return;
765 
766 	mutex_lock(&rdev->devlist_mtx);
767 	list_del_rcu(&wdev->list);
768 	rdev->devlist_generation++;
769 
770 	switch (wdev->iftype) {
771 	case NL80211_IFTYPE_P2P_DEVICE:
772 		if (!wdev->p2p_started)
773 			break;
774 		rdev->ops->stop_p2p_device(&rdev->wiphy, wdev);
775 		wdev->p2p_started = false;
776 		rdev->opencount--;
777 		break;
778 	default:
779 		WARN_ON_ONCE(1);
780 		break;
781 	}
782 	mutex_unlock(&rdev->devlist_mtx);
783 }
784 EXPORT_SYMBOL(cfg80211_unregister_wdev);
785 
786 static struct device_type wiphy_type = {
787 	.name	= "wlan",
788 };
789 
790 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
791 			       enum nl80211_iftype iftype, int num)
792 {
793 	ASSERT_RTNL();
794 
795 	rdev->num_running_ifaces += num;
796 	if (iftype == NL80211_IFTYPE_MONITOR)
797 		rdev->num_running_monitor_ifaces += num;
798 }
799 
800 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
801 					 unsigned long state,
802 					 void *ndev)
803 {
804 	struct net_device *dev = ndev;
805 	struct wireless_dev *wdev = dev->ieee80211_ptr;
806 	struct cfg80211_registered_device *rdev;
807 	int ret;
808 
809 	if (!wdev)
810 		return NOTIFY_DONE;
811 
812 	rdev = wiphy_to_dev(wdev->wiphy);
813 
814 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
815 
816 	switch (state) {
817 	case NETDEV_POST_INIT:
818 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
819 		break;
820 	case NETDEV_REGISTER:
821 		/*
822 		 * NB: cannot take rdev->mtx here because this may be
823 		 * called within code protected by it when interfaces
824 		 * are added with nl80211.
825 		 */
826 		mutex_init(&wdev->mtx);
827 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
828 		INIT_LIST_HEAD(&wdev->event_list);
829 		spin_lock_init(&wdev->event_lock);
830 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
831 		spin_lock_init(&wdev->mgmt_registrations_lock);
832 
833 		mutex_lock(&rdev->devlist_mtx);
834 		wdev->identifier = ++rdev->wdev_id;
835 		list_add_rcu(&wdev->list, &rdev->wdev_list);
836 		rdev->devlist_generation++;
837 		/* can only change netns with wiphy */
838 		dev->features |= NETIF_F_NETNS_LOCAL;
839 
840 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
841 				      "phy80211")) {
842 			pr_err("failed to add phy80211 symlink to netdev!\n");
843 		}
844 		wdev->netdev = dev;
845 		wdev->sme_state = CFG80211_SME_IDLE;
846 		mutex_unlock(&rdev->devlist_mtx);
847 #ifdef CONFIG_CFG80211_WEXT
848 		wdev->wext.default_key = -1;
849 		wdev->wext.default_mgmt_key = -1;
850 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
851 #endif
852 
853 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
854 			wdev->ps = true;
855 		else
856 			wdev->ps = false;
857 		/* allow mac80211 to determine the timeout */
858 		wdev->ps_timeout = -1;
859 
860 		if (!dev->ethtool_ops)
861 			dev->ethtool_ops = &cfg80211_ethtool_ops;
862 
863 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
864 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
865 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
866 			dev->priv_flags |= IFF_DONT_BRIDGE;
867 		break;
868 	case NETDEV_GOING_DOWN:
869 		switch (wdev->iftype) {
870 		case NL80211_IFTYPE_ADHOC:
871 			cfg80211_leave_ibss(rdev, dev, true);
872 			break;
873 		case NL80211_IFTYPE_P2P_CLIENT:
874 		case NL80211_IFTYPE_STATION:
875 			mutex_lock(&rdev->sched_scan_mtx);
876 			__cfg80211_stop_sched_scan(rdev, false);
877 			mutex_unlock(&rdev->sched_scan_mtx);
878 
879 			wdev_lock(wdev);
880 #ifdef CONFIG_CFG80211_WEXT
881 			kfree(wdev->wext.ie);
882 			wdev->wext.ie = NULL;
883 			wdev->wext.ie_len = 0;
884 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
885 #endif
886 			__cfg80211_disconnect(rdev, dev,
887 					      WLAN_REASON_DEAUTH_LEAVING, true);
888 			cfg80211_mlme_down(rdev, dev);
889 			wdev_unlock(wdev);
890 			break;
891 		case NL80211_IFTYPE_MESH_POINT:
892 			cfg80211_leave_mesh(rdev, dev);
893 			break;
894 		case NL80211_IFTYPE_AP:
895 			cfg80211_stop_ap(rdev, dev);
896 			break;
897 		default:
898 			break;
899 		}
900 		wdev->beacon_interval = 0;
901 		break;
902 	case NETDEV_DOWN:
903 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);
904 		dev_hold(dev);
905 		queue_work(cfg80211_wq, &wdev->cleanup_work);
906 		break;
907 	case NETDEV_UP:
908 		/*
909 		 * If we have a really quick DOWN/UP succession we may
910 		 * have this work still pending ... cancel it and see
911 		 * if it was pending, in which case we need to account
912 		 * for some of the work it would have done.
913 		 */
914 		if (cancel_work_sync(&wdev->cleanup_work)) {
915 			mutex_lock(&rdev->devlist_mtx);
916 			rdev->opencount--;
917 			mutex_unlock(&rdev->devlist_mtx);
918 			dev_put(dev);
919 		}
920 		cfg80211_update_iface_num(rdev, wdev->iftype, 1);
921 		cfg80211_lock_rdev(rdev);
922 		mutex_lock(&rdev->devlist_mtx);
923 		wdev_lock(wdev);
924 		switch (wdev->iftype) {
925 #ifdef CONFIG_CFG80211_WEXT
926 		case NL80211_IFTYPE_ADHOC:
927 			cfg80211_ibss_wext_join(rdev, wdev);
928 			break;
929 		case NL80211_IFTYPE_STATION:
930 			cfg80211_mgd_wext_connect(rdev, wdev);
931 			break;
932 #endif
933 #ifdef CONFIG_MAC80211_MESH
934 		case NL80211_IFTYPE_MESH_POINT:
935 			{
936 				/* backward compat code... */
937 				struct mesh_setup setup;
938 				memcpy(&setup, &default_mesh_setup,
939 						sizeof(setup));
940 				 /* back compat only needed for mesh_id */
941 				setup.mesh_id = wdev->ssid;
942 				setup.mesh_id_len = wdev->mesh_id_up_len;
943 				if (wdev->mesh_id_up_len)
944 					__cfg80211_join_mesh(rdev, dev,
945 							&setup,
946 							&default_mesh_config);
947 				break;
948 			}
949 #endif
950 		default:
951 			break;
952 		}
953 		wdev_unlock(wdev);
954 		rdev->opencount++;
955 		mutex_unlock(&rdev->devlist_mtx);
956 		cfg80211_unlock_rdev(rdev);
957 
958 		/*
959 		 * Configure power management to the driver here so that its
960 		 * correctly set also after interface type changes etc.
961 		 */
962 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
963 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
964 		    rdev->ops->set_power_mgmt)
965 			if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
966 						      wdev->ps,
967 						      wdev->ps_timeout)) {
968 				/* assume this means it's off */
969 				wdev->ps = false;
970 			}
971 		break;
972 	case NETDEV_UNREGISTER:
973 		/*
974 		 * NB: cannot take rdev->mtx here because this may be
975 		 * called within code protected by it when interfaces
976 		 * are removed with nl80211.
977 		 */
978 		mutex_lock(&rdev->devlist_mtx);
979 		/*
980 		 * It is possible to get NETDEV_UNREGISTER
981 		 * multiple times. To detect that, check
982 		 * that the interface is still on the list
983 		 * of registered interfaces, and only then
984 		 * remove and clean it up.
985 		 */
986 		if (!list_empty(&wdev->list)) {
987 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
988 			list_del_rcu(&wdev->list);
989 			rdev->devlist_generation++;
990 			cfg80211_mlme_purge_registrations(wdev);
991 #ifdef CONFIG_CFG80211_WEXT
992 			kfree(wdev->wext.keys);
993 #endif
994 		}
995 		mutex_unlock(&rdev->devlist_mtx);
996 		/*
997 		 * synchronise (so that we won't find this netdev
998 		 * from other code any more) and then clear the list
999 		 * head so that the above code can safely check for
1000 		 * !list_empty() to avoid double-cleanup.
1001 		 */
1002 		synchronize_rcu();
1003 		INIT_LIST_HEAD(&wdev->list);
1004 		/*
1005 		 * Ensure that all events have been processed and
1006 		 * freed.
1007 		 */
1008 		cfg80211_process_wdev_events(wdev);
1009 		break;
1010 	case NETDEV_PRE_UP:
1011 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1012 			return notifier_from_errno(-EOPNOTSUPP);
1013 		if (rfkill_blocked(rdev->rfkill))
1014 			return notifier_from_errno(-ERFKILL);
1015 		mutex_lock(&rdev->devlist_mtx);
1016 		ret = cfg80211_can_add_interface(rdev, wdev->iftype);
1017 		mutex_unlock(&rdev->devlist_mtx);
1018 		if (ret)
1019 			return notifier_from_errno(ret);
1020 		break;
1021 	}
1022 
1023 	return NOTIFY_DONE;
1024 }
1025 
1026 static struct notifier_block cfg80211_netdev_notifier = {
1027 	.notifier_call = cfg80211_netdev_notifier_call,
1028 };
1029 
1030 static void __net_exit cfg80211_pernet_exit(struct net *net)
1031 {
1032 	struct cfg80211_registered_device *rdev;
1033 
1034 	rtnl_lock();
1035 	mutex_lock(&cfg80211_mutex);
1036 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1037 		if (net_eq(wiphy_net(&rdev->wiphy), net))
1038 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1039 	}
1040 	mutex_unlock(&cfg80211_mutex);
1041 	rtnl_unlock();
1042 }
1043 
1044 static struct pernet_operations cfg80211_pernet_ops = {
1045 	.exit = cfg80211_pernet_exit,
1046 };
1047 
1048 static int __init cfg80211_init(void)
1049 {
1050 	int err;
1051 
1052 	err = register_pernet_device(&cfg80211_pernet_ops);
1053 	if (err)
1054 		goto out_fail_pernet;
1055 
1056 	err = wiphy_sysfs_init();
1057 	if (err)
1058 		goto out_fail_sysfs;
1059 
1060 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1061 	if (err)
1062 		goto out_fail_notifier;
1063 
1064 	err = nl80211_init();
1065 	if (err)
1066 		goto out_fail_nl80211;
1067 
1068 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1069 
1070 	err = regulatory_init();
1071 	if (err)
1072 		goto out_fail_reg;
1073 
1074 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1075 	if (!cfg80211_wq)
1076 		goto out_fail_wq;
1077 
1078 	return 0;
1079 
1080 out_fail_wq:
1081 	regulatory_exit();
1082 out_fail_reg:
1083 	debugfs_remove(ieee80211_debugfs_dir);
1084 out_fail_nl80211:
1085 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1086 out_fail_notifier:
1087 	wiphy_sysfs_exit();
1088 out_fail_sysfs:
1089 	unregister_pernet_device(&cfg80211_pernet_ops);
1090 out_fail_pernet:
1091 	return err;
1092 }
1093 subsys_initcall(cfg80211_init);
1094 
1095 static void __exit cfg80211_exit(void)
1096 {
1097 	debugfs_remove(ieee80211_debugfs_dir);
1098 	nl80211_exit();
1099 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1100 	wiphy_sysfs_exit();
1101 	regulatory_exit();
1102 	unregister_pernet_device(&cfg80211_pernet_ops);
1103 	destroy_workqueue(cfg80211_wq);
1104 }
1105 module_exit(cfg80211_exit);
1106