xref: /openbmc/linux/net/wireless/core.c (revision c819e2cf)
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 /* exported functions */
324 
325 struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
326 			   const char *requested_name)
327 {
328 	static atomic_t wiphy_counter = ATOMIC_INIT(0);
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 	rdev->wiphy_idx = atomic_inc_return(&wiphy_counter);
351 
352 	if (unlikely(rdev->wiphy_idx < 0)) {
353 		/* ugh, wrapped! */
354 		atomic_dec(&wiphy_counter);
355 		kfree(rdev);
356 		return NULL;
357 	}
358 
359 	/* atomic_inc_return makes it start at 1, make it start at 0 */
360 	rdev->wiphy_idx--;
361 
362 	/* give it a proper name */
363 	if (requested_name && requested_name[0]) {
364 		int rv;
365 
366 		rtnl_lock();
367 		rv = cfg80211_dev_check_name(rdev, requested_name);
368 
369 		if (rv < 0) {
370 			rtnl_unlock();
371 			goto use_default_name;
372 		}
373 
374 		rv = dev_set_name(&rdev->wiphy.dev, "%s", requested_name);
375 		rtnl_unlock();
376 		if (rv)
377 			goto use_default_name;
378 	} else {
379 use_default_name:
380 		/* NOTE:  This is *probably* safe w/out holding rtnl because of
381 		 * the restrictions on phy names.  Probably this call could
382 		 * fail if some other part of the kernel (re)named a device
383 		 * phyX.  But, might should add some locking and check return
384 		 * value, and use a different name if this one exists?
385 		 */
386 		dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
387 	}
388 
389 	INIT_LIST_HEAD(&rdev->wdev_list);
390 	INIT_LIST_HEAD(&rdev->beacon_registrations);
391 	spin_lock_init(&rdev->beacon_registrations_lock);
392 	spin_lock_init(&rdev->bss_lock);
393 	INIT_LIST_HEAD(&rdev->bss_list);
394 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
395 	INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
396 	INIT_DELAYED_WORK(&rdev->dfs_update_channels_wk,
397 			  cfg80211_dfs_channels_update_work);
398 #ifdef CONFIG_CFG80211_WEXT
399 	rdev->wiphy.wext = &cfg80211_wext_handler;
400 #endif
401 
402 	device_initialize(&rdev->wiphy.dev);
403 	rdev->wiphy.dev.class = &ieee80211_class;
404 	rdev->wiphy.dev.platform_data = rdev;
405 
406 	INIT_LIST_HEAD(&rdev->destroy_list);
407 	spin_lock_init(&rdev->destroy_list_lock);
408 	INIT_WORK(&rdev->destroy_work, cfg80211_destroy_iface_wk);
409 
410 #ifdef CONFIG_CFG80211_DEFAULT_PS
411 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
412 #endif
413 
414 	wiphy_net_set(&rdev->wiphy, &init_net);
415 
416 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
417 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
418 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
419 				   &rdev->rfkill_ops, rdev);
420 
421 	if (!rdev->rfkill) {
422 		kfree(rdev);
423 		return NULL;
424 	}
425 
426 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
427 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
428 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
429 
430 	init_waitqueue_head(&rdev->dev_wait);
431 
432 	/*
433 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
434 	 * Fragmentation and RTS threshold are disabled by default with the
435 	 * special -1 value.
436 	 */
437 	rdev->wiphy.retry_short = 7;
438 	rdev->wiphy.retry_long = 4;
439 	rdev->wiphy.frag_threshold = (u32) -1;
440 	rdev->wiphy.rts_threshold = (u32) -1;
441 	rdev->wiphy.coverage_class = 0;
442 
443 	rdev->wiphy.max_num_csa_counters = 1;
444 
445 	return &rdev->wiphy;
446 }
447 EXPORT_SYMBOL(wiphy_new_nm);
448 
449 static int wiphy_verify_combinations(struct wiphy *wiphy)
450 {
451 	const struct ieee80211_iface_combination *c;
452 	int i, j;
453 
454 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
455 		u32 cnt = 0;
456 		u16 all_iftypes = 0;
457 
458 		c = &wiphy->iface_combinations[i];
459 
460 		/*
461 		 * Combinations with just one interface aren't real,
462 		 * however we make an exception for DFS.
463 		 */
464 		if (WARN_ON((c->max_interfaces < 2) && !c->radar_detect_widths))
465 			return -EINVAL;
466 
467 		/* Need at least one channel */
468 		if (WARN_ON(!c->num_different_channels))
469 			return -EINVAL;
470 
471 		/*
472 		 * Put a sane limit on maximum number of different
473 		 * channels to simplify channel accounting code.
474 		 */
475 		if (WARN_ON(c->num_different_channels >
476 				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
477 			return -EINVAL;
478 
479 		/* DFS only works on one channel. */
480 		if (WARN_ON(c->radar_detect_widths &&
481 			    (c->num_different_channels > 1)))
482 			return -EINVAL;
483 
484 		if (WARN_ON(!c->n_limits))
485 			return -EINVAL;
486 
487 		for (j = 0; j < c->n_limits; j++) {
488 			u16 types = c->limits[j].types;
489 
490 			/* interface types shouldn't overlap */
491 			if (WARN_ON(types & all_iftypes))
492 				return -EINVAL;
493 			all_iftypes |= types;
494 
495 			if (WARN_ON(!c->limits[j].max))
496 				return -EINVAL;
497 
498 			/* Shouldn't list software iftypes in combinations! */
499 			if (WARN_ON(wiphy->software_iftypes & types))
500 				return -EINVAL;
501 
502 			/* Only a single P2P_DEVICE can be allowed */
503 			if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
504 				    c->limits[j].max > 1))
505 				return -EINVAL;
506 
507 			cnt += c->limits[j].max;
508 			/*
509 			 * Don't advertise an unsupported type
510 			 * in a combination.
511 			 */
512 			if (WARN_ON((wiphy->interface_modes & types) != types))
513 				return -EINVAL;
514 		}
515 
516 		/* You can't even choose that many! */
517 		if (WARN_ON(cnt < c->max_interfaces))
518 			return -EINVAL;
519 	}
520 
521 	return 0;
522 }
523 
524 int wiphy_register(struct wiphy *wiphy)
525 {
526 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
527 	int res;
528 	enum ieee80211_band band;
529 	struct ieee80211_supported_band *sband;
530 	bool have_band = false;
531 	int i;
532 	u16 ifmodes = wiphy->interface_modes;
533 
534 #ifdef CONFIG_PM
535 	if (WARN_ON(wiphy->wowlan &&
536 		    (wiphy->wowlan->flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
537 		    !(wiphy->wowlan->flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
538 		return -EINVAL;
539 	if (WARN_ON(wiphy->wowlan &&
540 		    !wiphy->wowlan->flags && !wiphy->wowlan->n_patterns &&
541 		    !wiphy->wowlan->tcp))
542 		return -EINVAL;
543 #endif
544 	if (WARN_ON((wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH) &&
545 		    (!rdev->ops->tdls_channel_switch ||
546 		     !rdev->ops->tdls_cancel_channel_switch)))
547 		return -EINVAL;
548 
549 	/*
550 	 * if a wiphy has unsupported modes for regulatory channel enforcement,
551 	 * opt-out of enforcement checking
552 	 */
553 	if (wiphy->interface_modes & ~(BIT(NL80211_IFTYPE_STATION) |
554 				       BIT(NL80211_IFTYPE_P2P_CLIENT) |
555 				       BIT(NL80211_IFTYPE_AP) |
556 				       BIT(NL80211_IFTYPE_P2P_GO) |
557 				       BIT(NL80211_IFTYPE_ADHOC) |
558 				       BIT(NL80211_IFTYPE_P2P_DEVICE) |
559 				       BIT(NL80211_IFTYPE_AP_VLAN) |
560 				       BIT(NL80211_IFTYPE_MONITOR)))
561 		wiphy->regulatory_flags |= REGULATORY_IGNORE_STALE_KICKOFF;
562 
563 	if (WARN_ON(wiphy->coalesce &&
564 		    (!wiphy->coalesce->n_rules ||
565 		     !wiphy->coalesce->n_patterns) &&
566 		    (!wiphy->coalesce->pattern_min_len ||
567 		     wiphy->coalesce->pattern_min_len >
568 			wiphy->coalesce->pattern_max_len)))
569 		return -EINVAL;
570 
571 	if (WARN_ON(wiphy->ap_sme_capa &&
572 		    !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
573 		return -EINVAL;
574 
575 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
576 		return -EINVAL;
577 
578 	if (WARN_ON(wiphy->addresses &&
579 		    !is_zero_ether_addr(wiphy->perm_addr) &&
580 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
581 			   ETH_ALEN)))
582 		return -EINVAL;
583 
584 	if (WARN_ON(wiphy->max_acl_mac_addrs &&
585 		    (!(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME) ||
586 		     !rdev->ops->set_mac_acl)))
587 		return -EINVAL;
588 
589 	if (wiphy->addresses)
590 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
591 
592 	/* sanity check ifmodes */
593 	WARN_ON(!ifmodes);
594 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
595 	if (WARN_ON(ifmodes != wiphy->interface_modes))
596 		wiphy->interface_modes = ifmodes;
597 
598 	res = wiphy_verify_combinations(wiphy);
599 	if (res)
600 		return res;
601 
602 	/* sanity check supported bands/channels */
603 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
604 		sband = wiphy->bands[band];
605 		if (!sband)
606 			continue;
607 
608 		sband->band = band;
609 		if (WARN_ON(!sband->n_channels))
610 			return -EINVAL;
611 		/*
612 		 * on 60gHz band, there are no legacy rates, so
613 		 * n_bitrates is 0
614 		 */
615 		if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
616 			    !sband->n_bitrates))
617 			return -EINVAL;
618 
619 		/*
620 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
621 		 * modify the sband's ht data even if the driver uses a
622 		 * global structure for that.
623 		 */
624 		if (cfg80211_disable_40mhz_24ghz &&
625 		    band == IEEE80211_BAND_2GHZ &&
626 		    sband->ht_cap.ht_supported) {
627 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
628 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
629 		}
630 
631 		/*
632 		 * Since we use a u32 for rate bitmaps in
633 		 * ieee80211_get_response_rate, we cannot
634 		 * have more than 32 legacy rates.
635 		 */
636 		if (WARN_ON(sband->n_bitrates > 32))
637 			return -EINVAL;
638 
639 		for (i = 0; i < sband->n_channels; i++) {
640 			sband->channels[i].orig_flags =
641 				sband->channels[i].flags;
642 			sband->channels[i].orig_mag = INT_MAX;
643 			sband->channels[i].orig_mpwr =
644 				sband->channels[i].max_power;
645 			sband->channels[i].band = band;
646 		}
647 
648 		have_band = true;
649 	}
650 
651 	if (!have_band) {
652 		WARN_ON(1);
653 		return -EINVAL;
654 	}
655 
656 #ifdef CONFIG_PM
657 	if (WARN_ON(rdev->wiphy.wowlan && rdev->wiphy.wowlan->n_patterns &&
658 		    (!rdev->wiphy.wowlan->pattern_min_len ||
659 		     rdev->wiphy.wowlan->pattern_min_len >
660 				rdev->wiphy.wowlan->pattern_max_len)))
661 		return -EINVAL;
662 #endif
663 
664 	/* check and set up bitrates */
665 	ieee80211_set_bitrate_flags(wiphy);
666 
667 	rdev->wiphy.features |= NL80211_FEATURE_SCAN_FLUSH;
668 
669 	rtnl_lock();
670 	res = device_add(&rdev->wiphy.dev);
671 	if (res) {
672 		rtnl_unlock();
673 		return res;
674 	}
675 
676 	/* set up regulatory info */
677 	wiphy_regulatory_register(wiphy);
678 
679 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
680 	cfg80211_rdev_list_generation++;
681 
682 	/* add to debugfs */
683 	rdev->wiphy.debugfsdir =
684 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
685 				   ieee80211_debugfs_dir);
686 	if (IS_ERR(rdev->wiphy.debugfsdir))
687 		rdev->wiphy.debugfsdir = NULL;
688 
689 	cfg80211_debugfs_rdev_add(rdev);
690 	nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
691 
692 	if (wiphy->regulatory_flags & REGULATORY_CUSTOM_REG) {
693 		struct regulatory_request request;
694 
695 		request.wiphy_idx = get_wiphy_idx(wiphy);
696 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
697 		request.alpha2[0] = '9';
698 		request.alpha2[1] = '9';
699 
700 		nl80211_send_reg_change_event(&request);
701 	}
702 
703 	rdev->wiphy.registered = true;
704 	rtnl_unlock();
705 
706 	res = rfkill_register(rdev->rfkill);
707 	if (res) {
708 		rfkill_destroy(rdev->rfkill);
709 		rdev->rfkill = NULL;
710 		wiphy_unregister(&rdev->wiphy);
711 		return res;
712 	}
713 
714 	return 0;
715 }
716 EXPORT_SYMBOL(wiphy_register);
717 
718 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
719 {
720 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
721 
722 	if (!rdev->ops->rfkill_poll)
723 		return;
724 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
725 	rfkill_resume_polling(rdev->rfkill);
726 }
727 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
728 
729 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
730 {
731 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
732 
733 	rfkill_pause_polling(rdev->rfkill);
734 }
735 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
736 
737 void wiphy_unregister(struct wiphy *wiphy)
738 {
739 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
740 
741 	wait_event(rdev->dev_wait, ({
742 		int __count;
743 		rtnl_lock();
744 		__count = rdev->opencount;
745 		rtnl_unlock();
746 		__count == 0; }));
747 
748 	if (rdev->rfkill)
749 		rfkill_unregister(rdev->rfkill);
750 
751 	rtnl_lock();
752 	nl80211_notify_wiphy(rdev, NL80211_CMD_DEL_WIPHY);
753 	rdev->wiphy.registered = false;
754 
755 	WARN_ON(!list_empty(&rdev->wdev_list));
756 
757 	/*
758 	 * First remove the hardware from everywhere, this makes
759 	 * it impossible to find from userspace.
760 	 */
761 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
762 	list_del_rcu(&rdev->list);
763 	synchronize_rcu();
764 
765 	/*
766 	 * If this device got a regulatory hint tell core its
767 	 * free to listen now to a new shiny device regulatory hint
768 	 */
769 	wiphy_regulatory_deregister(wiphy);
770 
771 	cfg80211_rdev_list_generation++;
772 	device_del(&rdev->wiphy.dev);
773 
774 	rtnl_unlock();
775 
776 	flush_work(&rdev->scan_done_wk);
777 	cancel_work_sync(&rdev->conn_work);
778 	flush_work(&rdev->event_work);
779 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
780 	flush_work(&rdev->destroy_work);
781 
782 #ifdef CONFIG_PM
783 	if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
784 		rdev_set_wakeup(rdev, false);
785 #endif
786 	cfg80211_rdev_free_wowlan(rdev);
787 	cfg80211_rdev_free_coalesce(rdev);
788 }
789 EXPORT_SYMBOL(wiphy_unregister);
790 
791 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
792 {
793 	struct cfg80211_internal_bss *scan, *tmp;
794 	struct cfg80211_beacon_registration *reg, *treg;
795 	rfkill_destroy(rdev->rfkill);
796 	list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
797 		list_del(&reg->list);
798 		kfree(reg);
799 	}
800 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
801 		cfg80211_put_bss(&rdev->wiphy, &scan->pub);
802 	kfree(rdev);
803 }
804 
805 void wiphy_free(struct wiphy *wiphy)
806 {
807 	put_device(&wiphy->dev);
808 }
809 EXPORT_SYMBOL(wiphy_free);
810 
811 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
812 {
813 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
814 
815 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
816 		schedule_work(&rdev->rfkill_sync);
817 }
818 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
819 
820 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
821 {
822 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
823 
824 	ASSERT_RTNL();
825 
826 	if (WARN_ON(wdev->netdev))
827 		return;
828 
829 	list_del_rcu(&wdev->list);
830 	rdev->devlist_generation++;
831 
832 	switch (wdev->iftype) {
833 	case NL80211_IFTYPE_P2P_DEVICE:
834 		cfg80211_stop_p2p_device(rdev, wdev);
835 		break;
836 	default:
837 		WARN_ON_ONCE(1);
838 		break;
839 	}
840 }
841 EXPORT_SYMBOL(cfg80211_unregister_wdev);
842 
843 static const struct device_type wiphy_type = {
844 	.name	= "wlan",
845 };
846 
847 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
848 			       enum nl80211_iftype iftype, int num)
849 {
850 	ASSERT_RTNL();
851 
852 	rdev->num_running_ifaces += num;
853 	if (iftype == NL80211_IFTYPE_MONITOR)
854 		rdev->num_running_monitor_ifaces += num;
855 }
856 
857 void __cfg80211_leave(struct cfg80211_registered_device *rdev,
858 		      struct wireless_dev *wdev)
859 {
860 	struct net_device *dev = wdev->netdev;
861 
862 	ASSERT_RTNL();
863 	ASSERT_WDEV_LOCK(wdev);
864 
865 	switch (wdev->iftype) {
866 	case NL80211_IFTYPE_ADHOC:
867 		__cfg80211_leave_ibss(rdev, dev, true);
868 		break;
869 	case NL80211_IFTYPE_P2P_CLIENT:
870 	case NL80211_IFTYPE_STATION:
871 		if (rdev->sched_scan_req && dev == rdev->sched_scan_req->dev)
872 			__cfg80211_stop_sched_scan(rdev, false);
873 
874 #ifdef CONFIG_CFG80211_WEXT
875 		kfree(wdev->wext.ie);
876 		wdev->wext.ie = NULL;
877 		wdev->wext.ie_len = 0;
878 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
879 #endif
880 		cfg80211_disconnect(rdev, dev,
881 				    WLAN_REASON_DEAUTH_LEAVING, true);
882 		break;
883 	case NL80211_IFTYPE_MESH_POINT:
884 		__cfg80211_leave_mesh(rdev, dev);
885 		break;
886 	case NL80211_IFTYPE_AP:
887 	case NL80211_IFTYPE_P2P_GO:
888 		__cfg80211_stop_ap(rdev, dev, true);
889 		break;
890 	case NL80211_IFTYPE_OCB:
891 		__cfg80211_leave_ocb(rdev, dev);
892 		break;
893 	case NL80211_IFTYPE_WDS:
894 		/* must be handled by mac80211/driver, has no APIs */
895 		break;
896 	case NL80211_IFTYPE_P2P_DEVICE:
897 		/* cannot happen, has no netdev */
898 		break;
899 	case NL80211_IFTYPE_AP_VLAN:
900 	case NL80211_IFTYPE_MONITOR:
901 		/* nothing to do */
902 		break;
903 	case NL80211_IFTYPE_UNSPECIFIED:
904 	case NUM_NL80211_IFTYPES:
905 		/* invalid */
906 		break;
907 	}
908 }
909 
910 void cfg80211_leave(struct cfg80211_registered_device *rdev,
911 		    struct wireless_dev *wdev)
912 {
913 	wdev_lock(wdev);
914 	__cfg80211_leave(rdev, wdev);
915 	wdev_unlock(wdev);
916 }
917 
918 void cfg80211_stop_iface(struct wiphy *wiphy, struct wireless_dev *wdev,
919 			 gfp_t gfp)
920 {
921 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
922 	struct cfg80211_event *ev;
923 	unsigned long flags;
924 
925 	trace_cfg80211_stop_iface(wiphy, wdev);
926 
927 	ev = kzalloc(sizeof(*ev), gfp);
928 	if (!ev)
929 		return;
930 
931 	ev->type = EVENT_STOPPED;
932 
933 	spin_lock_irqsave(&wdev->event_lock, flags);
934 	list_add_tail(&ev->list, &wdev->event_list);
935 	spin_unlock_irqrestore(&wdev->event_lock, flags);
936 	queue_work(cfg80211_wq, &rdev->event_work);
937 }
938 EXPORT_SYMBOL(cfg80211_stop_iface);
939 
940 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
941 					 unsigned long state, void *ptr)
942 {
943 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
944 	struct wireless_dev *wdev = dev->ieee80211_ptr;
945 	struct cfg80211_registered_device *rdev;
946 
947 	if (!wdev)
948 		return NOTIFY_DONE;
949 
950 	rdev = wiphy_to_rdev(wdev->wiphy);
951 
952 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
953 
954 	switch (state) {
955 	case NETDEV_POST_INIT:
956 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
957 		break;
958 	case NETDEV_REGISTER:
959 		/*
960 		 * NB: cannot take rdev->mtx here because this may be
961 		 * called within code protected by it when interfaces
962 		 * are added with nl80211.
963 		 */
964 		mutex_init(&wdev->mtx);
965 		INIT_LIST_HEAD(&wdev->event_list);
966 		spin_lock_init(&wdev->event_lock);
967 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
968 		spin_lock_init(&wdev->mgmt_registrations_lock);
969 
970 		wdev->identifier = ++rdev->wdev_id;
971 		list_add_rcu(&wdev->list, &rdev->wdev_list);
972 		rdev->devlist_generation++;
973 		/* can only change netns with wiphy */
974 		dev->features |= NETIF_F_NETNS_LOCAL;
975 
976 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
977 				      "phy80211")) {
978 			pr_err("failed to add phy80211 symlink to netdev!\n");
979 		}
980 		wdev->netdev = dev;
981 #ifdef CONFIG_CFG80211_WEXT
982 		wdev->wext.default_key = -1;
983 		wdev->wext.default_mgmt_key = -1;
984 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
985 #endif
986 
987 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
988 			wdev->ps = true;
989 		else
990 			wdev->ps = false;
991 		/* allow mac80211 to determine the timeout */
992 		wdev->ps_timeout = -1;
993 
994 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
995 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
996 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
997 			dev->priv_flags |= IFF_DONT_BRIDGE;
998 		break;
999 	case NETDEV_GOING_DOWN:
1000 		cfg80211_leave(rdev, wdev);
1001 		break;
1002 	case NETDEV_DOWN:
1003 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);
1004 		if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
1005 			if (WARN_ON(!rdev->scan_req->notified))
1006 				rdev->scan_req->aborted = true;
1007 			___cfg80211_scan_done(rdev, false);
1008 		}
1009 
1010 		if (WARN_ON(rdev->sched_scan_req &&
1011 			    rdev->sched_scan_req->dev == wdev->netdev)) {
1012 			__cfg80211_stop_sched_scan(rdev, false);
1013 		}
1014 
1015 		rdev->opencount--;
1016 		wake_up(&rdev->dev_wait);
1017 		break;
1018 	case NETDEV_UP:
1019 		cfg80211_update_iface_num(rdev, wdev->iftype, 1);
1020 		wdev_lock(wdev);
1021 		switch (wdev->iftype) {
1022 #ifdef CONFIG_CFG80211_WEXT
1023 		case NL80211_IFTYPE_ADHOC:
1024 			cfg80211_ibss_wext_join(rdev, wdev);
1025 			break;
1026 		case NL80211_IFTYPE_STATION:
1027 			cfg80211_mgd_wext_connect(rdev, wdev);
1028 			break;
1029 #endif
1030 #ifdef CONFIG_MAC80211_MESH
1031 		case NL80211_IFTYPE_MESH_POINT:
1032 			{
1033 				/* backward compat code... */
1034 				struct mesh_setup setup;
1035 				memcpy(&setup, &default_mesh_setup,
1036 						sizeof(setup));
1037 				 /* back compat only needed for mesh_id */
1038 				setup.mesh_id = wdev->ssid;
1039 				setup.mesh_id_len = wdev->mesh_id_up_len;
1040 				if (wdev->mesh_id_up_len)
1041 					__cfg80211_join_mesh(rdev, dev,
1042 							&setup,
1043 							&default_mesh_config);
1044 				break;
1045 			}
1046 #endif
1047 		default:
1048 			break;
1049 		}
1050 		wdev_unlock(wdev);
1051 		rdev->opencount++;
1052 
1053 		/*
1054 		 * Configure power management to the driver here so that its
1055 		 * correctly set also after interface type changes etc.
1056 		 */
1057 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
1058 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
1059 		    rdev->ops->set_power_mgmt)
1060 			if (rdev_set_power_mgmt(rdev, dev, wdev->ps,
1061 						wdev->ps_timeout)) {
1062 				/* assume this means it's off */
1063 				wdev->ps = false;
1064 			}
1065 		break;
1066 	case NETDEV_UNREGISTER:
1067 		/*
1068 		 * It is possible to get NETDEV_UNREGISTER
1069 		 * multiple times. To detect that, check
1070 		 * that the interface is still on the list
1071 		 * of registered interfaces, and only then
1072 		 * remove and clean it up.
1073 		 */
1074 		if (!list_empty(&wdev->list)) {
1075 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
1076 			list_del_rcu(&wdev->list);
1077 			rdev->devlist_generation++;
1078 			cfg80211_mlme_purge_registrations(wdev);
1079 #ifdef CONFIG_CFG80211_WEXT
1080 			kzfree(wdev->wext.keys);
1081 #endif
1082 		}
1083 		/*
1084 		 * synchronise (so that we won't find this netdev
1085 		 * from other code any more) and then clear the list
1086 		 * head so that the above code can safely check for
1087 		 * !list_empty() to avoid double-cleanup.
1088 		 */
1089 		synchronize_rcu();
1090 		INIT_LIST_HEAD(&wdev->list);
1091 		/*
1092 		 * Ensure that all events have been processed and
1093 		 * freed.
1094 		 */
1095 		cfg80211_process_wdev_events(wdev);
1096 
1097 		if (WARN_ON(wdev->current_bss)) {
1098 			cfg80211_unhold_bss(wdev->current_bss);
1099 			cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
1100 			wdev->current_bss = NULL;
1101 		}
1102 		break;
1103 	case NETDEV_PRE_UP:
1104 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1105 			return notifier_from_errno(-EOPNOTSUPP);
1106 		if (rfkill_blocked(rdev->rfkill))
1107 			return notifier_from_errno(-ERFKILL);
1108 		break;
1109 	default:
1110 		return NOTIFY_DONE;
1111 	}
1112 
1113 	return NOTIFY_OK;
1114 }
1115 
1116 static struct notifier_block cfg80211_netdev_notifier = {
1117 	.notifier_call = cfg80211_netdev_notifier_call,
1118 };
1119 
1120 static void __net_exit cfg80211_pernet_exit(struct net *net)
1121 {
1122 	struct cfg80211_registered_device *rdev;
1123 
1124 	rtnl_lock();
1125 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1126 		if (net_eq(wiphy_net(&rdev->wiphy), net))
1127 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1128 	}
1129 	rtnl_unlock();
1130 }
1131 
1132 static struct pernet_operations cfg80211_pernet_ops = {
1133 	.exit = cfg80211_pernet_exit,
1134 };
1135 
1136 static int __init cfg80211_init(void)
1137 {
1138 	int err;
1139 
1140 	err = register_pernet_device(&cfg80211_pernet_ops);
1141 	if (err)
1142 		goto out_fail_pernet;
1143 
1144 	err = wiphy_sysfs_init();
1145 	if (err)
1146 		goto out_fail_sysfs;
1147 
1148 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1149 	if (err)
1150 		goto out_fail_notifier;
1151 
1152 	err = nl80211_init();
1153 	if (err)
1154 		goto out_fail_nl80211;
1155 
1156 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1157 
1158 	err = regulatory_init();
1159 	if (err)
1160 		goto out_fail_reg;
1161 
1162 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1163 	if (!cfg80211_wq) {
1164 		err = -ENOMEM;
1165 		goto out_fail_wq;
1166 	}
1167 
1168 	return 0;
1169 
1170 out_fail_wq:
1171 	regulatory_exit();
1172 out_fail_reg:
1173 	debugfs_remove(ieee80211_debugfs_dir);
1174 out_fail_nl80211:
1175 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1176 out_fail_notifier:
1177 	wiphy_sysfs_exit();
1178 out_fail_sysfs:
1179 	unregister_pernet_device(&cfg80211_pernet_ops);
1180 out_fail_pernet:
1181 	return err;
1182 }
1183 subsys_initcall(cfg80211_init);
1184 
1185 static void __exit cfg80211_exit(void)
1186 {
1187 	debugfs_remove(ieee80211_debugfs_dir);
1188 	nl80211_exit();
1189 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1190 	wiphy_sysfs_exit();
1191 	regulatory_exit();
1192 	unregister_pernet_device(&cfg80211_pernet_ops);
1193 	destroy_workqueue(cfg80211_wq);
1194 }
1195 module_exit(cfg80211_exit);
1196