xref: /openbmc/linux/net/wireless/core.c (revision 4f3db074)
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010		Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2013-2014  Intel Mobile Communications GmbH
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/if.h>
11 #include <linux/module.h>
12 #include <linux/err.h>
13 #include <linux/list.h>
14 #include <linux/slab.h>
15 #include <linux/nl80211.h>
16 #include <linux/debugfs.h>
17 #include <linux/notifier.h>
18 #include <linux/device.h>
19 #include <linux/etherdevice.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/sched.h>
22 #include <net/genetlink.h>
23 #include <net/cfg80211.h>
24 #include "nl80211.h"
25 #include "core.h"
26 #include "sysfs.h"
27 #include "debugfs.h"
28 #include "wext-compat.h"
29 #include "rdev-ops.h"
30 
31 /* name for sysfs, %d is appended */
32 #define PHY_NAME "phy"
33 
34 MODULE_AUTHOR("Johannes Berg");
35 MODULE_LICENSE("GPL");
36 MODULE_DESCRIPTION("wireless configuration support");
37 MODULE_ALIAS_GENL_FAMILY(NL80211_GENL_NAME);
38 
39 /* RCU-protected (and RTNL for writers) */
40 LIST_HEAD(cfg80211_rdev_list);
41 int cfg80211_rdev_list_generation;
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 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
55 {
56 	struct cfg80211_registered_device *result = NULL, *rdev;
57 
58 	ASSERT_RTNL();
59 
60 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
61 		if (rdev->wiphy_idx == wiphy_idx) {
62 			result = rdev;
63 			break;
64 		}
65 	}
66 
67 	return result;
68 }
69 
70 int get_wiphy_idx(struct wiphy *wiphy)
71 {
72 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
73 
74 	return rdev->wiphy_idx;
75 }
76 
77 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
78 {
79 	struct cfg80211_registered_device *rdev;
80 
81 	ASSERT_RTNL();
82 
83 	rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
84 	if (!rdev)
85 		return NULL;
86 	return &rdev->wiphy;
87 }
88 
89 static int cfg80211_dev_check_name(struct cfg80211_registered_device *rdev,
90 				   const char *newname)
91 {
92 	struct cfg80211_registered_device *rdev2;
93 	int wiphy_idx, taken = -1, digits;
94 
95 	ASSERT_RTNL();
96 
97 	/* prohibit calling the thing phy%d when %d is not its number */
98 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
99 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
100 		/* count number of places needed to print wiphy_idx */
101 		digits = 1;
102 		while (wiphy_idx /= 10)
103 			digits++;
104 		/*
105 		 * deny the name if it is phy<idx> where <idx> is printed
106 		 * without leading zeroes. taken == strlen(newname) here
107 		 */
108 		if (taken == strlen(PHY_NAME) + digits)
109 			return -EINVAL;
110 	}
111 
112 	/* Ensure another device does not already have this name. */
113 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
114 		if (strcmp(newname, wiphy_name(&rdev2->wiphy)) == 0)
115 			return -EINVAL;
116 
117 	return 0;
118 }
119 
120 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
121 			char *newname)
122 {
123 	int result;
124 
125 	ASSERT_RTNL();
126 
127 	/* Ignore nop renames */
128 	if (strcmp(newname, wiphy_name(&rdev->wiphy)) == 0)
129 		return 0;
130 
131 	result = cfg80211_dev_check_name(rdev, newname);
132 	if (result < 0)
133 		return result;
134 
135 	result = device_rename(&rdev->wiphy.dev, newname);
136 	if (result)
137 		return result;
138 
139 	if (rdev->wiphy.debugfsdir &&
140 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
141 			    rdev->wiphy.debugfsdir,
142 			    rdev->wiphy.debugfsdir->d_parent,
143 			    newname))
144 		pr_err("failed to rename debugfs dir to %s!\n", newname);
145 
146 	nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
147 
148 	return 0;
149 }
150 
151 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
152 			  struct net *net)
153 {
154 	struct wireless_dev *wdev;
155 	int err = 0;
156 
157 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
158 		return -EOPNOTSUPP;
159 
160 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
161 		if (!wdev->netdev)
162 			continue;
163 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
164 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
165 		if (err)
166 			break;
167 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
168 	}
169 
170 	if (err) {
171 		/* failed -- clean up to old netns */
172 		net = wiphy_net(&rdev->wiphy);
173 
174 		list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,
175 						     list) {
176 			if (!wdev->netdev)
177 				continue;
178 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
179 			err = dev_change_net_namespace(wdev->netdev, net,
180 							"wlan%d");
181 			WARN_ON(err);
182 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
183 		}
184 
185 		return err;
186 	}
187 
188 	wiphy_net_set(&rdev->wiphy, net);
189 
190 	err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
191 	WARN_ON(err);
192 
193 	return 0;
194 }
195 
196 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
197 {
198 	struct cfg80211_registered_device *rdev = data;
199 
200 	rdev_rfkill_poll(rdev);
201 }
202 
203 void cfg80211_stop_p2p_device(struct cfg80211_registered_device *rdev,
204 			      struct wireless_dev *wdev)
205 {
206 	ASSERT_RTNL();
207 
208 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_P2P_DEVICE))
209 		return;
210 
211 	if (!wdev->p2p_started)
212 		return;
213 
214 	rdev_stop_p2p_device(rdev, wdev);
215 	wdev->p2p_started = false;
216 
217 	rdev->opencount--;
218 
219 	if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
220 		if (WARN_ON(!rdev->scan_req->notified))
221 			rdev->scan_req->aborted = true;
222 		___cfg80211_scan_done(rdev, false);
223 	}
224 }
225 
226 void cfg80211_shutdown_all_interfaces(struct wiphy *wiphy)
227 {
228 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
229 	struct wireless_dev *wdev;
230 
231 	ASSERT_RTNL();
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 			cfg80211_stop_p2p_device(rdev, wdev);
242 			break;
243 		default:
244 			break;
245 		}
246 	}
247 }
248 EXPORT_SYMBOL_GPL(cfg80211_shutdown_all_interfaces);
249 
250 static int cfg80211_rfkill_set_block(void *data, bool blocked)
251 {
252 	struct cfg80211_registered_device *rdev = data;
253 
254 	if (!blocked)
255 		return 0;
256 
257 	rtnl_lock();
258 	cfg80211_shutdown_all_interfaces(&rdev->wiphy);
259 	rtnl_unlock();
260 
261 	return 0;
262 }
263 
264 static void cfg80211_rfkill_sync_work(struct work_struct *work)
265 {
266 	struct cfg80211_registered_device *rdev;
267 
268 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
269 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
270 }
271 
272 static void cfg80211_event_work(struct work_struct *work)
273 {
274 	struct cfg80211_registered_device *rdev;
275 
276 	rdev = container_of(work, struct cfg80211_registered_device,
277 			    event_work);
278 
279 	rtnl_lock();
280 	cfg80211_process_rdev_events(rdev);
281 	rtnl_unlock();
282 }
283 
284 void cfg80211_destroy_ifaces(struct cfg80211_registered_device *rdev)
285 {
286 	struct cfg80211_iface_destroy *item;
287 
288 	ASSERT_RTNL();
289 
290 	spin_lock_irq(&rdev->destroy_list_lock);
291 	while ((item = list_first_entry_or_null(&rdev->destroy_list,
292 						struct cfg80211_iface_destroy,
293 						list))) {
294 		struct wireless_dev *wdev, *tmp;
295 		u32 nlportid = item->nlportid;
296 
297 		list_del(&item->list);
298 		kfree(item);
299 		spin_unlock_irq(&rdev->destroy_list_lock);
300 
301 		list_for_each_entry_safe(wdev, tmp, &rdev->wdev_list, list) {
302 			if (nlportid == wdev->owner_nlportid)
303 				rdev_del_virtual_intf(rdev, wdev);
304 		}
305 
306 		spin_lock_irq(&rdev->destroy_list_lock);
307 	}
308 	spin_unlock_irq(&rdev->destroy_list_lock);
309 }
310 
311 static void cfg80211_destroy_iface_wk(struct work_struct *work)
312 {
313 	struct cfg80211_registered_device *rdev;
314 
315 	rdev = container_of(work, struct cfg80211_registered_device,
316 			    destroy_work);
317 
318 	rtnl_lock();
319 	cfg80211_destroy_ifaces(rdev);
320 	rtnl_unlock();
321 }
322 
323 static void cfg80211_sched_scan_stop_wk(struct work_struct *work)
324 {
325 	struct cfg80211_registered_device *rdev;
326 
327 	rdev = container_of(work, struct cfg80211_registered_device,
328 			   sched_scan_stop_wk);
329 
330 	rtnl_lock();
331 
332 	__cfg80211_stop_sched_scan(rdev, false);
333 
334 	rtnl_unlock();
335 }
336 
337 /* exported functions */
338 
339 struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
340 			   const char *requested_name)
341 {
342 	static atomic_t wiphy_counter = ATOMIC_INIT(0);
343 
344 	struct cfg80211_registered_device *rdev;
345 	int alloc_size;
346 
347 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
348 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
349 	WARN_ON(ops->connect && !ops->disconnect);
350 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
351 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
352 	WARN_ON(ops->add_station && !ops->del_station);
353 	WARN_ON(ops->add_mpath && !ops->del_mpath);
354 	WARN_ON(ops->join_mesh && !ops->leave_mesh);
355 
356 	alloc_size = sizeof(*rdev) + sizeof_priv;
357 
358 	rdev = kzalloc(alloc_size, GFP_KERNEL);
359 	if (!rdev)
360 		return NULL;
361 
362 	rdev->ops = ops;
363 
364 	rdev->wiphy_idx = atomic_inc_return(&wiphy_counter);
365 
366 	if (unlikely(rdev->wiphy_idx < 0)) {
367 		/* ugh, wrapped! */
368 		atomic_dec(&wiphy_counter);
369 		kfree(rdev);
370 		return NULL;
371 	}
372 
373 	/* atomic_inc_return makes it start at 1, make it start at 0 */
374 	rdev->wiphy_idx--;
375 
376 	/* give it a proper name */
377 	if (requested_name && requested_name[0]) {
378 		int rv;
379 
380 		rtnl_lock();
381 		rv = cfg80211_dev_check_name(rdev, requested_name);
382 
383 		if (rv < 0) {
384 			rtnl_unlock();
385 			goto use_default_name;
386 		}
387 
388 		rv = dev_set_name(&rdev->wiphy.dev, "%s", requested_name);
389 		rtnl_unlock();
390 		if (rv)
391 			goto use_default_name;
392 	} else {
393 use_default_name:
394 		/* NOTE:  This is *probably* safe w/out holding rtnl because of
395 		 * the restrictions on phy names.  Probably this call could
396 		 * fail if some other part of the kernel (re)named a device
397 		 * phyX.  But, might should add some locking and check return
398 		 * value, and use a different name if this one exists?
399 		 */
400 		dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
401 	}
402 
403 	INIT_LIST_HEAD(&rdev->wdev_list);
404 	INIT_LIST_HEAD(&rdev->beacon_registrations);
405 	spin_lock_init(&rdev->beacon_registrations_lock);
406 	spin_lock_init(&rdev->bss_lock);
407 	INIT_LIST_HEAD(&rdev->bss_list);
408 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
409 	INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
410 	INIT_DELAYED_WORK(&rdev->dfs_update_channels_wk,
411 			  cfg80211_dfs_channels_update_work);
412 #ifdef CONFIG_CFG80211_WEXT
413 	rdev->wiphy.wext = &cfg80211_wext_handler;
414 #endif
415 
416 	device_initialize(&rdev->wiphy.dev);
417 	rdev->wiphy.dev.class = &ieee80211_class;
418 	rdev->wiphy.dev.platform_data = rdev;
419 
420 	INIT_LIST_HEAD(&rdev->destroy_list);
421 	spin_lock_init(&rdev->destroy_list_lock);
422 	INIT_WORK(&rdev->destroy_work, cfg80211_destroy_iface_wk);
423 	INIT_WORK(&rdev->sched_scan_stop_wk, cfg80211_sched_scan_stop_wk);
424 
425 #ifdef CONFIG_CFG80211_DEFAULT_PS
426 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
427 #endif
428 
429 	wiphy_net_set(&rdev->wiphy, &init_net);
430 
431 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
432 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
433 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
434 				   &rdev->rfkill_ops, rdev);
435 
436 	if (!rdev->rfkill) {
437 		kfree(rdev);
438 		return NULL;
439 	}
440 
441 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
442 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
443 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
444 
445 	init_waitqueue_head(&rdev->dev_wait);
446 
447 	/*
448 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
449 	 * Fragmentation and RTS threshold are disabled by default with the
450 	 * special -1 value.
451 	 */
452 	rdev->wiphy.retry_short = 7;
453 	rdev->wiphy.retry_long = 4;
454 	rdev->wiphy.frag_threshold = (u32) -1;
455 	rdev->wiphy.rts_threshold = (u32) -1;
456 	rdev->wiphy.coverage_class = 0;
457 
458 	rdev->wiphy.max_num_csa_counters = 1;
459 
460 	return &rdev->wiphy;
461 }
462 EXPORT_SYMBOL(wiphy_new_nm);
463 
464 static int wiphy_verify_combinations(struct wiphy *wiphy)
465 {
466 	const struct ieee80211_iface_combination *c;
467 	int i, j;
468 
469 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
470 		u32 cnt = 0;
471 		u16 all_iftypes = 0;
472 
473 		c = &wiphy->iface_combinations[i];
474 
475 		/*
476 		 * Combinations with just one interface aren't real,
477 		 * however we make an exception for DFS.
478 		 */
479 		if (WARN_ON((c->max_interfaces < 2) && !c->radar_detect_widths))
480 			return -EINVAL;
481 
482 		/* Need at least one channel */
483 		if (WARN_ON(!c->num_different_channels))
484 			return -EINVAL;
485 
486 		/*
487 		 * Put a sane limit on maximum number of different
488 		 * channels to simplify channel accounting code.
489 		 */
490 		if (WARN_ON(c->num_different_channels >
491 				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
492 			return -EINVAL;
493 
494 		/* DFS only works on one channel. */
495 		if (WARN_ON(c->radar_detect_widths &&
496 			    (c->num_different_channels > 1)))
497 			return -EINVAL;
498 
499 		if (WARN_ON(!c->n_limits))
500 			return -EINVAL;
501 
502 		for (j = 0; j < c->n_limits; j++) {
503 			u16 types = c->limits[j].types;
504 
505 			/* interface types shouldn't overlap */
506 			if (WARN_ON(types & all_iftypes))
507 				return -EINVAL;
508 			all_iftypes |= types;
509 
510 			if (WARN_ON(!c->limits[j].max))
511 				return -EINVAL;
512 
513 			/* Shouldn't list software iftypes in combinations! */
514 			if (WARN_ON(wiphy->software_iftypes & types))
515 				return -EINVAL;
516 
517 			/* Only a single P2P_DEVICE can be allowed */
518 			if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
519 				    c->limits[j].max > 1))
520 				return -EINVAL;
521 
522 			cnt += c->limits[j].max;
523 			/*
524 			 * Don't advertise an unsupported type
525 			 * in a combination.
526 			 */
527 			if (WARN_ON((wiphy->interface_modes & types) != types))
528 				return -EINVAL;
529 		}
530 
531 		/* You can't even choose that many! */
532 		if (WARN_ON(cnt < c->max_interfaces))
533 			return -EINVAL;
534 	}
535 
536 	return 0;
537 }
538 
539 int wiphy_register(struct wiphy *wiphy)
540 {
541 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
542 	int res;
543 	enum ieee80211_band band;
544 	struct ieee80211_supported_band *sband;
545 	bool have_band = false;
546 	int i;
547 	u16 ifmodes = wiphy->interface_modes;
548 
549 #ifdef CONFIG_PM
550 	if (WARN_ON(wiphy->wowlan &&
551 		    (wiphy->wowlan->flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
552 		    !(wiphy->wowlan->flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
553 		return -EINVAL;
554 	if (WARN_ON(wiphy->wowlan &&
555 		    !wiphy->wowlan->flags && !wiphy->wowlan->n_patterns &&
556 		    !wiphy->wowlan->tcp))
557 		return -EINVAL;
558 #endif
559 	if (WARN_ON((wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH) &&
560 		    (!rdev->ops->tdls_channel_switch ||
561 		     !rdev->ops->tdls_cancel_channel_switch)))
562 		return -EINVAL;
563 
564 	/*
565 	 * if a wiphy has unsupported modes for regulatory channel enforcement,
566 	 * opt-out of enforcement checking
567 	 */
568 	if (wiphy->interface_modes & ~(BIT(NL80211_IFTYPE_STATION) |
569 				       BIT(NL80211_IFTYPE_P2P_CLIENT) |
570 				       BIT(NL80211_IFTYPE_AP) |
571 				       BIT(NL80211_IFTYPE_P2P_GO) |
572 				       BIT(NL80211_IFTYPE_ADHOC) |
573 				       BIT(NL80211_IFTYPE_P2P_DEVICE) |
574 				       BIT(NL80211_IFTYPE_AP_VLAN) |
575 				       BIT(NL80211_IFTYPE_MONITOR)))
576 		wiphy->regulatory_flags |= REGULATORY_IGNORE_STALE_KICKOFF;
577 
578 	if (WARN_ON((wiphy->regulatory_flags & REGULATORY_WIPHY_SELF_MANAGED) &&
579 		    (wiphy->regulatory_flags &
580 					(REGULATORY_CUSTOM_REG |
581 					 REGULATORY_STRICT_REG |
582 					 REGULATORY_COUNTRY_IE_FOLLOW_POWER |
583 					 REGULATORY_COUNTRY_IE_IGNORE))))
584 		return -EINVAL;
585 
586 	if (WARN_ON(wiphy->coalesce &&
587 		    (!wiphy->coalesce->n_rules ||
588 		     !wiphy->coalesce->n_patterns) &&
589 		    (!wiphy->coalesce->pattern_min_len ||
590 		     wiphy->coalesce->pattern_min_len >
591 			wiphy->coalesce->pattern_max_len)))
592 		return -EINVAL;
593 
594 	if (WARN_ON(wiphy->ap_sme_capa &&
595 		    !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
596 		return -EINVAL;
597 
598 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
599 		return -EINVAL;
600 
601 	if (WARN_ON(wiphy->addresses &&
602 		    !is_zero_ether_addr(wiphy->perm_addr) &&
603 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
604 			   ETH_ALEN)))
605 		return -EINVAL;
606 
607 	if (WARN_ON(wiphy->max_acl_mac_addrs &&
608 		    (!(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME) ||
609 		     !rdev->ops->set_mac_acl)))
610 		return -EINVAL;
611 
612 	if (wiphy->addresses)
613 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
614 
615 	/* sanity check ifmodes */
616 	WARN_ON(!ifmodes);
617 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
618 	if (WARN_ON(ifmodes != wiphy->interface_modes))
619 		wiphy->interface_modes = ifmodes;
620 
621 	res = wiphy_verify_combinations(wiphy);
622 	if (res)
623 		return res;
624 
625 	/* sanity check supported bands/channels */
626 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
627 		sband = wiphy->bands[band];
628 		if (!sband)
629 			continue;
630 
631 		sband->band = band;
632 		if (WARN_ON(!sband->n_channels))
633 			return -EINVAL;
634 		/*
635 		 * on 60gHz band, there are no legacy rates, so
636 		 * n_bitrates is 0
637 		 */
638 		if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
639 			    !sband->n_bitrates))
640 			return -EINVAL;
641 
642 		/*
643 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
644 		 * modify the sband's ht data even if the driver uses a
645 		 * global structure for that.
646 		 */
647 		if (cfg80211_disable_40mhz_24ghz &&
648 		    band == IEEE80211_BAND_2GHZ &&
649 		    sband->ht_cap.ht_supported) {
650 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
651 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
652 		}
653 
654 		/*
655 		 * Since we use a u32 for rate bitmaps in
656 		 * ieee80211_get_response_rate, we cannot
657 		 * have more than 32 legacy rates.
658 		 */
659 		if (WARN_ON(sband->n_bitrates > 32))
660 			return -EINVAL;
661 
662 		for (i = 0; i < sband->n_channels; i++) {
663 			sband->channels[i].orig_flags =
664 				sband->channels[i].flags;
665 			sband->channels[i].orig_mag = INT_MAX;
666 			sband->channels[i].orig_mpwr =
667 				sband->channels[i].max_power;
668 			sband->channels[i].band = band;
669 		}
670 
671 		have_band = true;
672 	}
673 
674 	if (!have_band) {
675 		WARN_ON(1);
676 		return -EINVAL;
677 	}
678 
679 #ifdef CONFIG_PM
680 	if (WARN_ON(rdev->wiphy.wowlan && rdev->wiphy.wowlan->n_patterns &&
681 		    (!rdev->wiphy.wowlan->pattern_min_len ||
682 		     rdev->wiphy.wowlan->pattern_min_len >
683 				rdev->wiphy.wowlan->pattern_max_len)))
684 		return -EINVAL;
685 #endif
686 
687 	/* check and set up bitrates */
688 	ieee80211_set_bitrate_flags(wiphy);
689 
690 	rdev->wiphy.features |= NL80211_FEATURE_SCAN_FLUSH;
691 
692 	rtnl_lock();
693 	res = device_add(&rdev->wiphy.dev);
694 	if (res) {
695 		rtnl_unlock();
696 		return res;
697 	}
698 
699 	/* set up regulatory info */
700 	wiphy_regulatory_register(wiphy);
701 
702 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
703 	cfg80211_rdev_list_generation++;
704 
705 	/* add to debugfs */
706 	rdev->wiphy.debugfsdir =
707 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
708 				   ieee80211_debugfs_dir);
709 	if (IS_ERR(rdev->wiphy.debugfsdir))
710 		rdev->wiphy.debugfsdir = NULL;
711 
712 	cfg80211_debugfs_rdev_add(rdev);
713 	nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
714 
715 	if (wiphy->regulatory_flags & REGULATORY_CUSTOM_REG) {
716 		struct regulatory_request request;
717 
718 		request.wiphy_idx = get_wiphy_idx(wiphy);
719 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
720 		request.alpha2[0] = '9';
721 		request.alpha2[1] = '9';
722 
723 		nl80211_send_reg_change_event(&request);
724 	}
725 
726 	rdev->wiphy.registered = true;
727 	rtnl_unlock();
728 
729 	res = rfkill_register(rdev->rfkill);
730 	if (res) {
731 		rfkill_destroy(rdev->rfkill);
732 		rdev->rfkill = NULL;
733 		wiphy_unregister(&rdev->wiphy);
734 		return res;
735 	}
736 
737 	return 0;
738 }
739 EXPORT_SYMBOL(wiphy_register);
740 
741 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
742 {
743 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
744 
745 	if (!rdev->ops->rfkill_poll)
746 		return;
747 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
748 	rfkill_resume_polling(rdev->rfkill);
749 }
750 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
751 
752 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
753 {
754 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
755 
756 	rfkill_pause_polling(rdev->rfkill);
757 }
758 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
759 
760 void wiphy_unregister(struct wiphy *wiphy)
761 {
762 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
763 
764 	wait_event(rdev->dev_wait, ({
765 		int __count;
766 		rtnl_lock();
767 		__count = rdev->opencount;
768 		rtnl_unlock();
769 		__count == 0; }));
770 
771 	if (rdev->rfkill)
772 		rfkill_unregister(rdev->rfkill);
773 
774 	rtnl_lock();
775 	nl80211_notify_wiphy(rdev, NL80211_CMD_DEL_WIPHY);
776 	rdev->wiphy.registered = false;
777 
778 	WARN_ON(!list_empty(&rdev->wdev_list));
779 
780 	/*
781 	 * First remove the hardware from everywhere, this makes
782 	 * it impossible to find from userspace.
783 	 */
784 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
785 	list_del_rcu(&rdev->list);
786 	synchronize_rcu();
787 
788 	/*
789 	 * If this device got a regulatory hint tell core its
790 	 * free to listen now to a new shiny device regulatory hint
791 	 */
792 	wiphy_regulatory_deregister(wiphy);
793 
794 	cfg80211_rdev_list_generation++;
795 	device_del(&rdev->wiphy.dev);
796 
797 	rtnl_unlock();
798 
799 	flush_work(&rdev->scan_done_wk);
800 	cancel_work_sync(&rdev->conn_work);
801 	flush_work(&rdev->event_work);
802 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
803 	flush_work(&rdev->destroy_work);
804 	flush_work(&rdev->sched_scan_stop_wk);
805 
806 #ifdef CONFIG_PM
807 	if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
808 		rdev_set_wakeup(rdev, false);
809 #endif
810 	cfg80211_rdev_free_wowlan(rdev);
811 	cfg80211_rdev_free_coalesce(rdev);
812 }
813 EXPORT_SYMBOL(wiphy_unregister);
814 
815 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
816 {
817 	struct cfg80211_internal_bss *scan, *tmp;
818 	struct cfg80211_beacon_registration *reg, *treg;
819 	rfkill_destroy(rdev->rfkill);
820 	list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
821 		list_del(&reg->list);
822 		kfree(reg);
823 	}
824 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
825 		cfg80211_put_bss(&rdev->wiphy, &scan->pub);
826 	kfree(rdev);
827 }
828 
829 void wiphy_free(struct wiphy *wiphy)
830 {
831 	put_device(&wiphy->dev);
832 }
833 EXPORT_SYMBOL(wiphy_free);
834 
835 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
836 {
837 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
838 
839 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
840 		schedule_work(&rdev->rfkill_sync);
841 }
842 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
843 
844 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
845 {
846 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
847 
848 	ASSERT_RTNL();
849 
850 	if (WARN_ON(wdev->netdev))
851 		return;
852 
853 	list_del_rcu(&wdev->list);
854 	rdev->devlist_generation++;
855 
856 	switch (wdev->iftype) {
857 	case NL80211_IFTYPE_P2P_DEVICE:
858 		cfg80211_stop_p2p_device(rdev, wdev);
859 		break;
860 	default:
861 		WARN_ON_ONCE(1);
862 		break;
863 	}
864 }
865 EXPORT_SYMBOL(cfg80211_unregister_wdev);
866 
867 static const struct device_type wiphy_type = {
868 	.name	= "wlan",
869 };
870 
871 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
872 			       enum nl80211_iftype iftype, int num)
873 {
874 	ASSERT_RTNL();
875 
876 	rdev->num_running_ifaces += num;
877 	if (iftype == NL80211_IFTYPE_MONITOR)
878 		rdev->num_running_monitor_ifaces += num;
879 }
880 
881 void __cfg80211_leave(struct cfg80211_registered_device *rdev,
882 		      struct wireless_dev *wdev)
883 {
884 	struct net_device *dev = wdev->netdev;
885 	struct cfg80211_sched_scan_request *sched_scan_req;
886 
887 	ASSERT_RTNL();
888 	ASSERT_WDEV_LOCK(wdev);
889 
890 	switch (wdev->iftype) {
891 	case NL80211_IFTYPE_ADHOC:
892 		__cfg80211_leave_ibss(rdev, dev, true);
893 		break;
894 	case NL80211_IFTYPE_P2P_CLIENT:
895 	case NL80211_IFTYPE_STATION:
896 		sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
897 		if (sched_scan_req && dev == sched_scan_req->dev)
898 			__cfg80211_stop_sched_scan(rdev, false);
899 
900 #ifdef CONFIG_CFG80211_WEXT
901 		kfree(wdev->wext.ie);
902 		wdev->wext.ie = NULL;
903 		wdev->wext.ie_len = 0;
904 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
905 #endif
906 		cfg80211_disconnect(rdev, dev,
907 				    WLAN_REASON_DEAUTH_LEAVING, true);
908 		break;
909 	case NL80211_IFTYPE_MESH_POINT:
910 		__cfg80211_leave_mesh(rdev, dev);
911 		break;
912 	case NL80211_IFTYPE_AP:
913 	case NL80211_IFTYPE_P2P_GO:
914 		__cfg80211_stop_ap(rdev, dev, true);
915 		break;
916 	case NL80211_IFTYPE_OCB:
917 		__cfg80211_leave_ocb(rdev, dev);
918 		break;
919 	case NL80211_IFTYPE_WDS:
920 		/* must be handled by mac80211/driver, has no APIs */
921 		break;
922 	case NL80211_IFTYPE_P2P_DEVICE:
923 		/* cannot happen, has no netdev */
924 		break;
925 	case NL80211_IFTYPE_AP_VLAN:
926 	case NL80211_IFTYPE_MONITOR:
927 		/* nothing to do */
928 		break;
929 	case NL80211_IFTYPE_UNSPECIFIED:
930 	case NUM_NL80211_IFTYPES:
931 		/* invalid */
932 		break;
933 	}
934 }
935 
936 void cfg80211_leave(struct cfg80211_registered_device *rdev,
937 		    struct wireless_dev *wdev)
938 {
939 	wdev_lock(wdev);
940 	__cfg80211_leave(rdev, wdev);
941 	wdev_unlock(wdev);
942 }
943 
944 void cfg80211_stop_iface(struct wiphy *wiphy, struct wireless_dev *wdev,
945 			 gfp_t gfp)
946 {
947 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
948 	struct cfg80211_event *ev;
949 	unsigned long flags;
950 
951 	trace_cfg80211_stop_iface(wiphy, wdev);
952 
953 	ev = kzalloc(sizeof(*ev), gfp);
954 	if (!ev)
955 		return;
956 
957 	ev->type = EVENT_STOPPED;
958 
959 	spin_lock_irqsave(&wdev->event_lock, flags);
960 	list_add_tail(&ev->list, &wdev->event_list);
961 	spin_unlock_irqrestore(&wdev->event_lock, flags);
962 	queue_work(cfg80211_wq, &rdev->event_work);
963 }
964 EXPORT_SYMBOL(cfg80211_stop_iface);
965 
966 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
967 					 unsigned long state, void *ptr)
968 {
969 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
970 	struct wireless_dev *wdev = dev->ieee80211_ptr;
971 	struct cfg80211_registered_device *rdev;
972 	struct cfg80211_sched_scan_request *sched_scan_req;
973 
974 	if (!wdev)
975 		return NOTIFY_DONE;
976 
977 	rdev = wiphy_to_rdev(wdev->wiphy);
978 
979 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
980 
981 	switch (state) {
982 	case NETDEV_POST_INIT:
983 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
984 		break;
985 	case NETDEV_REGISTER:
986 		/*
987 		 * NB: cannot take rdev->mtx here because this may be
988 		 * called within code protected by it when interfaces
989 		 * are added with nl80211.
990 		 */
991 		mutex_init(&wdev->mtx);
992 		INIT_LIST_HEAD(&wdev->event_list);
993 		spin_lock_init(&wdev->event_lock);
994 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
995 		spin_lock_init(&wdev->mgmt_registrations_lock);
996 
997 		wdev->identifier = ++rdev->wdev_id;
998 		list_add_rcu(&wdev->list, &rdev->wdev_list);
999 		rdev->devlist_generation++;
1000 		/* can only change netns with wiphy */
1001 		dev->features |= NETIF_F_NETNS_LOCAL;
1002 
1003 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
1004 				      "phy80211")) {
1005 			pr_err("failed to add phy80211 symlink to netdev!\n");
1006 		}
1007 		wdev->netdev = dev;
1008 #ifdef CONFIG_CFG80211_WEXT
1009 		wdev->wext.default_key = -1;
1010 		wdev->wext.default_mgmt_key = -1;
1011 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
1012 #endif
1013 
1014 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
1015 			wdev->ps = true;
1016 		else
1017 			wdev->ps = false;
1018 		/* allow mac80211 to determine the timeout */
1019 		wdev->ps_timeout = -1;
1020 
1021 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
1022 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
1023 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
1024 			dev->priv_flags |= IFF_DONT_BRIDGE;
1025 		break;
1026 	case NETDEV_GOING_DOWN:
1027 		cfg80211_leave(rdev, wdev);
1028 		break;
1029 	case NETDEV_DOWN:
1030 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);
1031 		if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
1032 			if (WARN_ON(!rdev->scan_req->notified))
1033 				rdev->scan_req->aborted = true;
1034 			___cfg80211_scan_done(rdev, false);
1035 		}
1036 
1037 		sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
1038 		if (WARN_ON(sched_scan_req &&
1039 			    sched_scan_req->dev == wdev->netdev)) {
1040 			__cfg80211_stop_sched_scan(rdev, false);
1041 		}
1042 
1043 		rdev->opencount--;
1044 		wake_up(&rdev->dev_wait);
1045 		break;
1046 	case NETDEV_UP:
1047 		cfg80211_update_iface_num(rdev, wdev->iftype, 1);
1048 		wdev_lock(wdev);
1049 		switch (wdev->iftype) {
1050 #ifdef CONFIG_CFG80211_WEXT
1051 		case NL80211_IFTYPE_ADHOC:
1052 			cfg80211_ibss_wext_join(rdev, wdev);
1053 			break;
1054 		case NL80211_IFTYPE_STATION:
1055 			cfg80211_mgd_wext_connect(rdev, wdev);
1056 			break;
1057 #endif
1058 #ifdef CONFIG_MAC80211_MESH
1059 		case NL80211_IFTYPE_MESH_POINT:
1060 			{
1061 				/* backward compat code... */
1062 				struct mesh_setup setup;
1063 				memcpy(&setup, &default_mesh_setup,
1064 						sizeof(setup));
1065 				 /* back compat only needed for mesh_id */
1066 				setup.mesh_id = wdev->ssid;
1067 				setup.mesh_id_len = wdev->mesh_id_up_len;
1068 				if (wdev->mesh_id_up_len)
1069 					__cfg80211_join_mesh(rdev, dev,
1070 							&setup,
1071 							&default_mesh_config);
1072 				break;
1073 			}
1074 #endif
1075 		default:
1076 			break;
1077 		}
1078 		wdev_unlock(wdev);
1079 		rdev->opencount++;
1080 
1081 		/*
1082 		 * Configure power management to the driver here so that its
1083 		 * correctly set also after interface type changes etc.
1084 		 */
1085 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
1086 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
1087 		    rdev->ops->set_power_mgmt)
1088 			if (rdev_set_power_mgmt(rdev, dev, wdev->ps,
1089 						wdev->ps_timeout)) {
1090 				/* assume this means it's off */
1091 				wdev->ps = false;
1092 			}
1093 		break;
1094 	case NETDEV_UNREGISTER:
1095 		/*
1096 		 * It is possible to get NETDEV_UNREGISTER
1097 		 * multiple times. To detect that, check
1098 		 * that the interface is still on the list
1099 		 * of registered interfaces, and only then
1100 		 * remove and clean it up.
1101 		 */
1102 		if (!list_empty(&wdev->list)) {
1103 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
1104 			list_del_rcu(&wdev->list);
1105 			rdev->devlist_generation++;
1106 			cfg80211_mlme_purge_registrations(wdev);
1107 #ifdef CONFIG_CFG80211_WEXT
1108 			kzfree(wdev->wext.keys);
1109 #endif
1110 		}
1111 		/*
1112 		 * synchronise (so that we won't find this netdev
1113 		 * from other code any more) and then clear the list
1114 		 * head so that the above code can safely check for
1115 		 * !list_empty() to avoid double-cleanup.
1116 		 */
1117 		synchronize_rcu();
1118 		INIT_LIST_HEAD(&wdev->list);
1119 		/*
1120 		 * Ensure that all events have been processed and
1121 		 * freed.
1122 		 */
1123 		cfg80211_process_wdev_events(wdev);
1124 
1125 		if (WARN_ON(wdev->current_bss)) {
1126 			cfg80211_unhold_bss(wdev->current_bss);
1127 			cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
1128 			wdev->current_bss = NULL;
1129 		}
1130 		break;
1131 	case NETDEV_PRE_UP:
1132 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1133 			return notifier_from_errno(-EOPNOTSUPP);
1134 		if (rfkill_blocked(rdev->rfkill))
1135 			return notifier_from_errno(-ERFKILL);
1136 		break;
1137 	default:
1138 		return NOTIFY_DONE;
1139 	}
1140 
1141 	return NOTIFY_OK;
1142 }
1143 
1144 static struct notifier_block cfg80211_netdev_notifier = {
1145 	.notifier_call = cfg80211_netdev_notifier_call,
1146 };
1147 
1148 static void __net_exit cfg80211_pernet_exit(struct net *net)
1149 {
1150 	struct cfg80211_registered_device *rdev;
1151 
1152 	rtnl_lock();
1153 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1154 		if (net_eq(wiphy_net(&rdev->wiphy), net))
1155 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1156 	}
1157 	rtnl_unlock();
1158 }
1159 
1160 static struct pernet_operations cfg80211_pernet_ops = {
1161 	.exit = cfg80211_pernet_exit,
1162 };
1163 
1164 static int __init cfg80211_init(void)
1165 {
1166 	int err;
1167 
1168 	err = register_pernet_device(&cfg80211_pernet_ops);
1169 	if (err)
1170 		goto out_fail_pernet;
1171 
1172 	err = wiphy_sysfs_init();
1173 	if (err)
1174 		goto out_fail_sysfs;
1175 
1176 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1177 	if (err)
1178 		goto out_fail_notifier;
1179 
1180 	err = nl80211_init();
1181 	if (err)
1182 		goto out_fail_nl80211;
1183 
1184 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1185 
1186 	err = regulatory_init();
1187 	if (err)
1188 		goto out_fail_reg;
1189 
1190 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1191 	if (!cfg80211_wq) {
1192 		err = -ENOMEM;
1193 		goto out_fail_wq;
1194 	}
1195 
1196 	return 0;
1197 
1198 out_fail_wq:
1199 	regulatory_exit();
1200 out_fail_reg:
1201 	debugfs_remove(ieee80211_debugfs_dir);
1202 	nl80211_exit();
1203 out_fail_nl80211:
1204 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1205 out_fail_notifier:
1206 	wiphy_sysfs_exit();
1207 out_fail_sysfs:
1208 	unregister_pernet_device(&cfg80211_pernet_ops);
1209 out_fail_pernet:
1210 	return err;
1211 }
1212 subsys_initcall(cfg80211_init);
1213 
1214 static void __exit cfg80211_exit(void)
1215 {
1216 	debugfs_remove(ieee80211_debugfs_dir);
1217 	nl80211_exit();
1218 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1219 	wiphy_sysfs_exit();
1220 	regulatory_exit();
1221 	unregister_pernet_device(&cfg80211_pernet_ops);
1222 	destroy_workqueue(cfg80211_wq);
1223 }
1224 module_exit(cfg80211_exit);
1225