xref: /openbmc/linux/net/wireless/core.c (revision 81d67439)
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 /* requires cfg80211_mutex to be held! */
100 struct cfg80211_registered_device *
101 __cfg80211_rdev_from_info(struct genl_info *info)
102 {
103 	int ifindex;
104 	struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
105 	struct net_device *dev;
106 	int err = -EINVAL;
107 
108 	assert_cfg80211_lock();
109 
110 	if (info->attrs[NL80211_ATTR_WIPHY]) {
111 		bywiphyidx = cfg80211_rdev_by_wiphy_idx(
112 				nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
113 		err = -ENODEV;
114 	}
115 
116 	if (info->attrs[NL80211_ATTR_IFINDEX]) {
117 		ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
118 		dev = dev_get_by_index(genl_info_net(info), ifindex);
119 		if (dev) {
120 			if (dev->ieee80211_ptr)
121 				byifidx =
122 					wiphy_to_dev(dev->ieee80211_ptr->wiphy);
123 			dev_put(dev);
124 		}
125 		err = -ENODEV;
126 	}
127 
128 	if (bywiphyidx && byifidx) {
129 		if (bywiphyidx != byifidx)
130 			return ERR_PTR(-EINVAL);
131 		else
132 			return bywiphyidx; /* == byifidx */
133 	}
134 	if (bywiphyidx)
135 		return bywiphyidx;
136 
137 	if (byifidx)
138 		return byifidx;
139 
140 	return ERR_PTR(err);
141 }
142 
143 struct cfg80211_registered_device *
144 cfg80211_get_dev_from_info(struct genl_info *info)
145 {
146 	struct cfg80211_registered_device *rdev;
147 
148 	mutex_lock(&cfg80211_mutex);
149 	rdev = __cfg80211_rdev_from_info(info);
150 
151 	/* if it is not an error we grab the lock on
152 	 * it to assure it won't be going away while
153 	 * we operate on it */
154 	if (!IS_ERR(rdev))
155 		mutex_lock(&rdev->mtx);
156 
157 	mutex_unlock(&cfg80211_mutex);
158 
159 	return rdev;
160 }
161 
162 struct cfg80211_registered_device *
163 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
164 {
165 	struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
166 	struct net_device *dev;
167 
168 	mutex_lock(&cfg80211_mutex);
169 	dev = dev_get_by_index(net, ifindex);
170 	if (!dev)
171 		goto out;
172 	if (dev->ieee80211_ptr) {
173 		rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
174 		mutex_lock(&rdev->mtx);
175 	} else
176 		rdev = ERR_PTR(-ENODEV);
177 	dev_put(dev);
178  out:
179 	mutex_unlock(&cfg80211_mutex);
180 	return rdev;
181 }
182 
183 /* requires cfg80211_mutex to be held */
184 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
185 			char *newname)
186 {
187 	struct cfg80211_registered_device *rdev2;
188 	int wiphy_idx, taken = -1, result, digits;
189 
190 	assert_cfg80211_lock();
191 
192 	/* prohibit calling the thing phy%d when %d is not its number */
193 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
194 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
195 		/* count number of places needed to print wiphy_idx */
196 		digits = 1;
197 		while (wiphy_idx /= 10)
198 			digits++;
199 		/*
200 		 * deny the name if it is phy<idx> where <idx> is printed
201 		 * without leading zeroes. taken == strlen(newname) here
202 		 */
203 		if (taken == strlen(PHY_NAME) + digits)
204 			return -EINVAL;
205 	}
206 
207 
208 	/* Ignore nop renames */
209 	if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
210 		return 0;
211 
212 	/* Ensure another device does not already have this name. */
213 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
214 		if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
215 			return -EINVAL;
216 
217 	result = device_rename(&rdev->wiphy.dev, newname);
218 	if (result)
219 		return result;
220 
221 	if (rdev->wiphy.debugfsdir &&
222 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
223 			    rdev->wiphy.debugfsdir,
224 			    rdev->wiphy.debugfsdir->d_parent,
225 			    newname))
226 		pr_err("failed to rename debugfs dir to %s!\n", newname);
227 
228 	nl80211_notify_dev_rename(rdev);
229 
230 	return 0;
231 }
232 
233 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
234 			  struct net *net)
235 {
236 	struct wireless_dev *wdev;
237 	int err = 0;
238 
239 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
240 		return -EOPNOTSUPP;
241 
242 	list_for_each_entry(wdev, &rdev->netdev_list, list) {
243 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
244 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
245 		if (err)
246 			break;
247 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
248 	}
249 
250 	if (err) {
251 		/* failed -- clean up to old netns */
252 		net = wiphy_net(&rdev->wiphy);
253 
254 		list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,
255 						     list) {
256 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
257 			err = dev_change_net_namespace(wdev->netdev, net,
258 							"wlan%d");
259 			WARN_ON(err);
260 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
261 		}
262 
263 		return err;
264 	}
265 
266 	wiphy_net_set(&rdev->wiphy, net);
267 
268 	err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
269 	WARN_ON(err);
270 
271 	return 0;
272 }
273 
274 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
275 {
276 	struct cfg80211_registered_device *rdev = data;
277 
278 	rdev->ops->rfkill_poll(&rdev->wiphy);
279 }
280 
281 static int cfg80211_rfkill_set_block(void *data, bool blocked)
282 {
283 	struct cfg80211_registered_device *rdev = data;
284 	struct wireless_dev *wdev;
285 
286 	if (!blocked)
287 		return 0;
288 
289 	rtnl_lock();
290 	mutex_lock(&rdev->devlist_mtx);
291 
292 	list_for_each_entry(wdev, &rdev->netdev_list, list)
293 		dev_close(wdev->netdev);
294 
295 	mutex_unlock(&rdev->devlist_mtx);
296 	rtnl_unlock();
297 
298 	return 0;
299 }
300 
301 static void cfg80211_rfkill_sync_work(struct work_struct *work)
302 {
303 	struct cfg80211_registered_device *rdev;
304 
305 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
306 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
307 }
308 
309 static void cfg80211_event_work(struct work_struct *work)
310 {
311 	struct cfg80211_registered_device *rdev;
312 
313 	rdev = container_of(work, struct cfg80211_registered_device,
314 			    event_work);
315 
316 	rtnl_lock();
317 	cfg80211_lock_rdev(rdev);
318 
319 	cfg80211_process_rdev_events(rdev);
320 	cfg80211_unlock_rdev(rdev);
321 	rtnl_unlock();
322 }
323 
324 /* exported functions */
325 
326 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
327 {
328 	static int wiphy_counter;
329 
330 	struct cfg80211_registered_device *rdev;
331 	int alloc_size;
332 
333 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
334 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
335 	WARN_ON(ops->connect && !ops->disconnect);
336 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
337 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
338 	WARN_ON(ops->add_station && !ops->del_station);
339 	WARN_ON(ops->add_mpath && !ops->del_mpath);
340 	WARN_ON(ops->join_mesh && !ops->leave_mesh);
341 
342 	alloc_size = sizeof(*rdev) + sizeof_priv;
343 
344 	rdev = kzalloc(alloc_size, GFP_KERNEL);
345 	if (!rdev)
346 		return NULL;
347 
348 	rdev->ops = ops;
349 
350 	mutex_lock(&cfg80211_mutex);
351 
352 	rdev->wiphy_idx = wiphy_counter++;
353 
354 	if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
355 		wiphy_counter--;
356 		mutex_unlock(&cfg80211_mutex);
357 		/* ugh, wrapped! */
358 		kfree(rdev);
359 		return NULL;
360 	}
361 
362 	mutex_unlock(&cfg80211_mutex);
363 
364 	/* give it a proper name */
365 	dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
366 
367 	mutex_init(&rdev->mtx);
368 	mutex_init(&rdev->devlist_mtx);
369 	mutex_init(&rdev->sched_scan_mtx);
370 	INIT_LIST_HEAD(&rdev->netdev_list);
371 	spin_lock_init(&rdev->bss_lock);
372 	INIT_LIST_HEAD(&rdev->bss_list);
373 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
374 	INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
375 #ifdef CONFIG_CFG80211_WEXT
376 	rdev->wiphy.wext = &cfg80211_wext_handler;
377 #endif
378 
379 	device_initialize(&rdev->wiphy.dev);
380 	rdev->wiphy.dev.class = &ieee80211_class;
381 	rdev->wiphy.dev.platform_data = rdev;
382 
383 #ifdef CONFIG_CFG80211_DEFAULT_PS
384 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
385 #endif
386 
387 	wiphy_net_set(&rdev->wiphy, &init_net);
388 
389 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
390 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
391 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
392 				   &rdev->rfkill_ops, rdev);
393 
394 	if (!rdev->rfkill) {
395 		kfree(rdev);
396 		return NULL;
397 	}
398 
399 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
400 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
401 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
402 
403 	init_waitqueue_head(&rdev->dev_wait);
404 
405 	/*
406 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
407 	 * Fragmentation and RTS threshold are disabled by default with the
408 	 * special -1 value.
409 	 */
410 	rdev->wiphy.retry_short = 7;
411 	rdev->wiphy.retry_long = 4;
412 	rdev->wiphy.frag_threshold = (u32) -1;
413 	rdev->wiphy.rts_threshold = (u32) -1;
414 	rdev->wiphy.coverage_class = 0;
415 
416 	return &rdev->wiphy;
417 }
418 EXPORT_SYMBOL(wiphy_new);
419 
420 static int wiphy_verify_combinations(struct wiphy *wiphy)
421 {
422 	const struct ieee80211_iface_combination *c;
423 	int i, j;
424 
425 	/* If we have combinations enforce them */
426 	if (wiphy->n_iface_combinations)
427 		wiphy->flags |= WIPHY_FLAG_ENFORCE_COMBINATIONS;
428 
429 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
430 		u32 cnt = 0;
431 		u16 all_iftypes = 0;
432 
433 		c = &wiphy->iface_combinations[i];
434 
435 		/* Combinations with just one interface aren't real */
436 		if (WARN_ON(c->max_interfaces < 2))
437 			return -EINVAL;
438 
439 		/* Need at least one channel */
440 		if (WARN_ON(!c->num_different_channels))
441 			return -EINVAL;
442 
443 		if (WARN_ON(!c->n_limits))
444 			return -EINVAL;
445 
446 		for (j = 0; j < c->n_limits; j++) {
447 			u16 types = c->limits[j].types;
448 
449 			/*
450 			 * interface types shouldn't overlap, this is
451 			 * used in cfg80211_can_change_interface()
452 			 */
453 			if (WARN_ON(types & all_iftypes))
454 				return -EINVAL;
455 			all_iftypes |= types;
456 
457 			if (WARN_ON(!c->limits[j].max))
458 				return -EINVAL;
459 
460 			/* Shouldn't list software iftypes in combinations! */
461 			if (WARN_ON(wiphy->software_iftypes & types))
462 				return -EINVAL;
463 
464 			cnt += c->limits[j].max;
465 			/*
466 			 * Don't advertise an unsupported type
467 			 * in a combination.
468 			 */
469 			if (WARN_ON((wiphy->interface_modes & types) != types))
470 				return -EINVAL;
471 		}
472 
473 		/* You can't even choose that many! */
474 		if (WARN_ON(cnt < c->max_interfaces))
475 			return -EINVAL;
476 	}
477 
478 	return 0;
479 }
480 
481 int wiphy_register(struct wiphy *wiphy)
482 {
483 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
484 	int res;
485 	enum ieee80211_band band;
486 	struct ieee80211_supported_band *sband;
487 	bool have_band = false;
488 	int i;
489 	u16 ifmodes = wiphy->interface_modes;
490 
491 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
492 		return -EINVAL;
493 
494 	if (WARN_ON(wiphy->addresses &&
495 		    !is_zero_ether_addr(wiphy->perm_addr) &&
496 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
497 			   ETH_ALEN)))
498 		return -EINVAL;
499 
500 	if (wiphy->addresses)
501 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
502 
503 	/* sanity check ifmodes */
504 	WARN_ON(!ifmodes);
505 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
506 	if (WARN_ON(ifmodes != wiphy->interface_modes))
507 		wiphy->interface_modes = ifmodes;
508 
509 	res = wiphy_verify_combinations(wiphy);
510 	if (res)
511 		return res;
512 
513 	/* sanity check supported bands/channels */
514 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
515 		sband = wiphy->bands[band];
516 		if (!sband)
517 			continue;
518 
519 		sband->band = band;
520 
521 		if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
522 			return -EINVAL;
523 
524 		/*
525 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
526 		 * modify the sband's ht data even if the driver uses a
527 		 * global structure for that.
528 		 */
529 		if (cfg80211_disable_40mhz_24ghz &&
530 		    band == IEEE80211_BAND_2GHZ &&
531 		    sband->ht_cap.ht_supported) {
532 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
533 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
534 		}
535 
536 		/*
537 		 * Since we use a u32 for rate bitmaps in
538 		 * ieee80211_get_response_rate, we cannot
539 		 * have more than 32 legacy rates.
540 		 */
541 		if (WARN_ON(sband->n_bitrates > 32))
542 			return -EINVAL;
543 
544 		for (i = 0; i < sband->n_channels; i++) {
545 			sband->channels[i].orig_flags =
546 				sband->channels[i].flags;
547 			sband->channels[i].orig_mag =
548 				sband->channels[i].max_antenna_gain;
549 			sband->channels[i].orig_mpwr =
550 				sband->channels[i].max_power;
551 			sband->channels[i].band = band;
552 		}
553 
554 		have_band = true;
555 	}
556 
557 	if (!have_band) {
558 		WARN_ON(1);
559 		return -EINVAL;
560 	}
561 
562 	if (rdev->wiphy.wowlan.n_patterns) {
563 		if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
564 			    rdev->wiphy.wowlan.pattern_min_len >
565 			    rdev->wiphy.wowlan.pattern_max_len))
566 			return -EINVAL;
567 	}
568 
569 	/* check and set up bitrates */
570 	ieee80211_set_bitrate_flags(wiphy);
571 
572 	mutex_lock(&cfg80211_mutex);
573 
574 	res = device_add(&rdev->wiphy.dev);
575 	if (res) {
576 		mutex_unlock(&cfg80211_mutex);
577 		return res;
578 	}
579 
580 	/* set up regulatory info */
581 	wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
582 
583 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
584 	cfg80211_rdev_list_generation++;
585 
586 	/* add to debugfs */
587 	rdev->wiphy.debugfsdir =
588 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
589 				   ieee80211_debugfs_dir);
590 	if (IS_ERR(rdev->wiphy.debugfsdir))
591 		rdev->wiphy.debugfsdir = NULL;
592 
593 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
594 		struct regulatory_request request;
595 
596 		request.wiphy_idx = get_wiphy_idx(wiphy);
597 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
598 		request.alpha2[0] = '9';
599 		request.alpha2[1] = '9';
600 
601 		nl80211_send_reg_change_event(&request);
602 	}
603 
604 	cfg80211_debugfs_rdev_add(rdev);
605 	mutex_unlock(&cfg80211_mutex);
606 
607 	/*
608 	 * due to a locking dependency this has to be outside of the
609 	 * cfg80211_mutex lock
610 	 */
611 	res = rfkill_register(rdev->rfkill);
612 	if (res)
613 		goto out_rm_dev;
614 
615 	return 0;
616 
617 out_rm_dev:
618 	device_del(&rdev->wiphy.dev);
619 	return res;
620 }
621 EXPORT_SYMBOL(wiphy_register);
622 
623 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
624 {
625 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
626 
627 	if (!rdev->ops->rfkill_poll)
628 		return;
629 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
630 	rfkill_resume_polling(rdev->rfkill);
631 }
632 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
633 
634 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
635 {
636 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
637 
638 	rfkill_pause_polling(rdev->rfkill);
639 }
640 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
641 
642 void wiphy_unregister(struct wiphy *wiphy)
643 {
644 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
645 
646 	rfkill_unregister(rdev->rfkill);
647 
648 	/* protect the device list */
649 	mutex_lock(&cfg80211_mutex);
650 
651 	wait_event(rdev->dev_wait, ({
652 		int __count;
653 		mutex_lock(&rdev->devlist_mtx);
654 		__count = rdev->opencount;
655 		mutex_unlock(&rdev->devlist_mtx);
656 		__count == 0;}));
657 
658 	mutex_lock(&rdev->devlist_mtx);
659 	BUG_ON(!list_empty(&rdev->netdev_list));
660 	mutex_unlock(&rdev->devlist_mtx);
661 
662 	/*
663 	 * First remove the hardware from everywhere, this makes
664 	 * it impossible to find from userspace.
665 	 */
666 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
667 	list_del_rcu(&rdev->list);
668 	synchronize_rcu();
669 
670 	/*
671 	 * Try to grab rdev->mtx. If a command is still in progress,
672 	 * hopefully the driver will refuse it since it's tearing
673 	 * down the device already. We wait for this command to complete
674 	 * before unlinking the item from the list.
675 	 * Note: as codified by the BUG_ON above we cannot get here if
676 	 * a virtual interface is still present. Hence, we can only get
677 	 * to lock contention here if userspace issues a command that
678 	 * identified the hardware by wiphy index.
679 	 */
680 	cfg80211_lock_rdev(rdev);
681 	/* nothing */
682 	cfg80211_unlock_rdev(rdev);
683 
684 	/* If this device got a regulatory hint tell core its
685 	 * free to listen now to a new shiny device regulatory hint */
686 	reg_device_remove(wiphy);
687 
688 	cfg80211_rdev_list_generation++;
689 	device_del(&rdev->wiphy.dev);
690 
691 	mutex_unlock(&cfg80211_mutex);
692 
693 	flush_work(&rdev->scan_done_wk);
694 	cancel_work_sync(&rdev->conn_work);
695 	flush_work(&rdev->event_work);
696 }
697 EXPORT_SYMBOL(wiphy_unregister);
698 
699 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
700 {
701 	struct cfg80211_internal_bss *scan, *tmp;
702 	rfkill_destroy(rdev->rfkill);
703 	mutex_destroy(&rdev->mtx);
704 	mutex_destroy(&rdev->devlist_mtx);
705 	mutex_destroy(&rdev->sched_scan_mtx);
706 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
707 		cfg80211_put_bss(&scan->pub);
708 	cfg80211_rdev_free_wowlan(rdev);
709 	kfree(rdev);
710 }
711 
712 void wiphy_free(struct wiphy *wiphy)
713 {
714 	put_device(&wiphy->dev);
715 }
716 EXPORT_SYMBOL(wiphy_free);
717 
718 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
719 {
720 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
721 
722 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
723 		schedule_work(&rdev->rfkill_sync);
724 }
725 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
726 
727 static void wdev_cleanup_work(struct work_struct *work)
728 {
729 	struct wireless_dev *wdev;
730 	struct cfg80211_registered_device *rdev;
731 
732 	wdev = container_of(work, struct wireless_dev, cleanup_work);
733 	rdev = wiphy_to_dev(wdev->wiphy);
734 
735 	cfg80211_lock_rdev(rdev);
736 
737 	if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) {
738 		rdev->scan_req->aborted = true;
739 		___cfg80211_scan_done(rdev, true);
740 	}
741 
742 	cfg80211_unlock_rdev(rdev);
743 
744 	mutex_lock(&rdev->sched_scan_mtx);
745 
746 	if (WARN_ON(rdev->sched_scan_req &&
747 		    rdev->sched_scan_req->dev == wdev->netdev)) {
748 		__cfg80211_stop_sched_scan(rdev, false);
749 	}
750 
751 	mutex_unlock(&rdev->sched_scan_mtx);
752 
753 	mutex_lock(&rdev->devlist_mtx);
754 	rdev->opencount--;
755 	mutex_unlock(&rdev->devlist_mtx);
756 	wake_up(&rdev->dev_wait);
757 
758 	dev_put(wdev->netdev);
759 }
760 
761 static struct device_type wiphy_type = {
762 	.name	= "wlan",
763 };
764 
765 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
766 					 unsigned long state,
767 					 void *ndev)
768 {
769 	struct net_device *dev = ndev;
770 	struct wireless_dev *wdev = dev->ieee80211_ptr;
771 	struct cfg80211_registered_device *rdev;
772 	int ret;
773 
774 	if (!wdev)
775 		return NOTIFY_DONE;
776 
777 	rdev = wiphy_to_dev(wdev->wiphy);
778 
779 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
780 
781 	switch (state) {
782 	case NETDEV_POST_INIT:
783 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
784 		break;
785 	case NETDEV_REGISTER:
786 		/*
787 		 * NB: cannot take rdev->mtx here because this may be
788 		 * called within code protected by it when interfaces
789 		 * are added with nl80211.
790 		 */
791 		mutex_init(&wdev->mtx);
792 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
793 		INIT_LIST_HEAD(&wdev->event_list);
794 		spin_lock_init(&wdev->event_lock);
795 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
796 		spin_lock_init(&wdev->mgmt_registrations_lock);
797 
798 		mutex_lock(&rdev->devlist_mtx);
799 		list_add_rcu(&wdev->list, &rdev->netdev_list);
800 		rdev->devlist_generation++;
801 		/* can only change netns with wiphy */
802 		dev->features |= NETIF_F_NETNS_LOCAL;
803 
804 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
805 				      "phy80211")) {
806 			pr_err("failed to add phy80211 symlink to netdev!\n");
807 		}
808 		wdev->netdev = dev;
809 		wdev->sme_state = CFG80211_SME_IDLE;
810 		mutex_unlock(&rdev->devlist_mtx);
811 #ifdef CONFIG_CFG80211_WEXT
812 		wdev->wext.default_key = -1;
813 		wdev->wext.default_mgmt_key = -1;
814 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
815 #endif
816 
817 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
818 			wdev->ps = true;
819 		else
820 			wdev->ps = false;
821 		/* allow mac80211 to determine the timeout */
822 		wdev->ps_timeout = -1;
823 
824 		if (!dev->ethtool_ops)
825 			dev->ethtool_ops = &cfg80211_ethtool_ops;
826 
827 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
828 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
829 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
830 			dev->priv_flags |= IFF_DONT_BRIDGE;
831 		break;
832 	case NETDEV_GOING_DOWN:
833 		switch (wdev->iftype) {
834 		case NL80211_IFTYPE_ADHOC:
835 			cfg80211_leave_ibss(rdev, dev, true);
836 			break;
837 		case NL80211_IFTYPE_P2P_CLIENT:
838 		case NL80211_IFTYPE_STATION:
839 			mutex_lock(&rdev->sched_scan_mtx);
840 			__cfg80211_stop_sched_scan(rdev, false);
841 			mutex_unlock(&rdev->sched_scan_mtx);
842 
843 			wdev_lock(wdev);
844 #ifdef CONFIG_CFG80211_WEXT
845 			kfree(wdev->wext.ie);
846 			wdev->wext.ie = NULL;
847 			wdev->wext.ie_len = 0;
848 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
849 #endif
850 			__cfg80211_disconnect(rdev, dev,
851 					      WLAN_REASON_DEAUTH_LEAVING, true);
852 			cfg80211_mlme_down(rdev, dev);
853 			wdev_unlock(wdev);
854 			break;
855 		case NL80211_IFTYPE_MESH_POINT:
856 			cfg80211_leave_mesh(rdev, dev);
857 			break;
858 		default:
859 			break;
860 		}
861 		wdev->beacon_interval = 0;
862 		break;
863 	case NETDEV_DOWN:
864 		dev_hold(dev);
865 		queue_work(cfg80211_wq, &wdev->cleanup_work);
866 		break;
867 	case NETDEV_UP:
868 		/*
869 		 * If we have a really quick DOWN/UP succession we may
870 		 * have this work still pending ... cancel it and see
871 		 * if it was pending, in which case we need to account
872 		 * for some of the work it would have done.
873 		 */
874 		if (cancel_work_sync(&wdev->cleanup_work)) {
875 			mutex_lock(&rdev->devlist_mtx);
876 			rdev->opencount--;
877 			mutex_unlock(&rdev->devlist_mtx);
878 			dev_put(dev);
879 		}
880 		cfg80211_lock_rdev(rdev);
881 		mutex_lock(&rdev->devlist_mtx);
882 		wdev_lock(wdev);
883 		switch (wdev->iftype) {
884 #ifdef CONFIG_CFG80211_WEXT
885 		case NL80211_IFTYPE_ADHOC:
886 			cfg80211_ibss_wext_join(rdev, wdev);
887 			break;
888 		case NL80211_IFTYPE_STATION:
889 			cfg80211_mgd_wext_connect(rdev, wdev);
890 			break;
891 #endif
892 #ifdef CONFIG_MAC80211_MESH
893 		case NL80211_IFTYPE_MESH_POINT:
894 			{
895 				/* backward compat code... */
896 				struct mesh_setup setup;
897 				memcpy(&setup, &default_mesh_setup,
898 						sizeof(setup));
899 				 /* back compat only needed for mesh_id */
900 				setup.mesh_id = wdev->ssid;
901 				setup.mesh_id_len = wdev->mesh_id_up_len;
902 				if (wdev->mesh_id_up_len)
903 					__cfg80211_join_mesh(rdev, dev,
904 							&setup,
905 							&default_mesh_config);
906 				break;
907 			}
908 #endif
909 		default:
910 			break;
911 		}
912 		wdev_unlock(wdev);
913 		rdev->opencount++;
914 		mutex_unlock(&rdev->devlist_mtx);
915 		cfg80211_unlock_rdev(rdev);
916 
917 		/*
918 		 * Configure power management to the driver here so that its
919 		 * correctly set also after interface type changes etc.
920 		 */
921 		if (wdev->iftype == NL80211_IFTYPE_STATION &&
922 		    rdev->ops->set_power_mgmt)
923 			if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
924 						      wdev->ps,
925 						      wdev->ps_timeout)) {
926 				/* assume this means it's off */
927 				wdev->ps = false;
928 			}
929 		break;
930 	case NETDEV_UNREGISTER:
931 		/*
932 		 * NB: cannot take rdev->mtx here because this may be
933 		 * called within code protected by it when interfaces
934 		 * are removed with nl80211.
935 		 */
936 		mutex_lock(&rdev->devlist_mtx);
937 		/*
938 		 * It is possible to get NETDEV_UNREGISTER
939 		 * multiple times. To detect that, check
940 		 * that the interface is still on the list
941 		 * of registered interfaces, and only then
942 		 * remove and clean it up.
943 		 */
944 		if (!list_empty(&wdev->list)) {
945 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
946 			list_del_rcu(&wdev->list);
947 			rdev->devlist_generation++;
948 			cfg80211_mlme_purge_registrations(wdev);
949 #ifdef CONFIG_CFG80211_WEXT
950 			kfree(wdev->wext.keys);
951 #endif
952 		}
953 		mutex_unlock(&rdev->devlist_mtx);
954 		/*
955 		 * synchronise (so that we won't find this netdev
956 		 * from other code any more) and then clear the list
957 		 * head so that the above code can safely check for
958 		 * !list_empty() to avoid double-cleanup.
959 		 */
960 		synchronize_rcu();
961 		INIT_LIST_HEAD(&wdev->list);
962 		break;
963 	case NETDEV_PRE_UP:
964 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
965 			return notifier_from_errno(-EOPNOTSUPP);
966 		if (rfkill_blocked(rdev->rfkill))
967 			return notifier_from_errno(-ERFKILL);
968 		ret = cfg80211_can_add_interface(rdev, wdev->iftype);
969 		if (ret)
970 			return notifier_from_errno(ret);
971 		break;
972 	}
973 
974 	return NOTIFY_DONE;
975 }
976 
977 static struct notifier_block cfg80211_netdev_notifier = {
978 	.notifier_call = cfg80211_netdev_notifier_call,
979 };
980 
981 static void __net_exit cfg80211_pernet_exit(struct net *net)
982 {
983 	struct cfg80211_registered_device *rdev;
984 
985 	rtnl_lock();
986 	mutex_lock(&cfg80211_mutex);
987 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
988 		if (net_eq(wiphy_net(&rdev->wiphy), net))
989 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
990 	}
991 	mutex_unlock(&cfg80211_mutex);
992 	rtnl_unlock();
993 }
994 
995 static struct pernet_operations cfg80211_pernet_ops = {
996 	.exit = cfg80211_pernet_exit,
997 };
998 
999 static int __init cfg80211_init(void)
1000 {
1001 	int err;
1002 
1003 	err = register_pernet_device(&cfg80211_pernet_ops);
1004 	if (err)
1005 		goto out_fail_pernet;
1006 
1007 	err = wiphy_sysfs_init();
1008 	if (err)
1009 		goto out_fail_sysfs;
1010 
1011 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1012 	if (err)
1013 		goto out_fail_notifier;
1014 
1015 	err = nl80211_init();
1016 	if (err)
1017 		goto out_fail_nl80211;
1018 
1019 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1020 
1021 	err = regulatory_init();
1022 	if (err)
1023 		goto out_fail_reg;
1024 
1025 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1026 	if (!cfg80211_wq)
1027 		goto out_fail_wq;
1028 
1029 	return 0;
1030 
1031 out_fail_wq:
1032 	regulatory_exit();
1033 out_fail_reg:
1034 	debugfs_remove(ieee80211_debugfs_dir);
1035 out_fail_nl80211:
1036 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1037 out_fail_notifier:
1038 	wiphy_sysfs_exit();
1039 out_fail_sysfs:
1040 	unregister_pernet_device(&cfg80211_pernet_ops);
1041 out_fail_pernet:
1042 	return err;
1043 }
1044 subsys_initcall(cfg80211_init);
1045 
1046 static void __exit cfg80211_exit(void)
1047 {
1048 	debugfs_remove(ieee80211_debugfs_dir);
1049 	nl80211_exit();
1050 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1051 	wiphy_sysfs_exit();
1052 	regulatory_exit();
1053 	unregister_pernet_device(&cfg80211_pernet_ops);
1054 	destroy_workqueue(cfg80211_wq);
1055 }
1056 module_exit(cfg80211_exit);
1057