xref: /linux/net/mac80211/iface.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
1 /*
2  * Interface handling (except master interface)
3  *
4  * Copyright 2002-2005, Instant802 Networks, Inc.
5  * Copyright 2005-2006, Devicescape Software, Inc.
6  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
7  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/if_arp.h>
16 #include <linux/netdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20 #include "ieee80211_i.h"
21 #include "sta_info.h"
22 #include "debugfs_netdev.h"
23 #include "mesh.h"
24 #include "led.h"
25 #include "driver-ops.h"
26 #include "wme.h"
27 #include "rate.h"
28 
29 /**
30  * DOC: Interface list locking
31  *
32  * The interface list in each struct ieee80211_local is protected
33  * three-fold:
34  *
35  * (1) modifications may only be done under the RTNL
36  * (2) modifications and readers are protected against each other by
37  *     the iflist_mtx.
38  * (3) modifications are done in an RCU manner so atomic readers
39  *     can traverse the list in RCU-safe blocks.
40  *
41  * As a consequence, reads (traversals) of the list can be protected
42  * by either the RTNL, the iflist_mtx or RCU.
43  */
44 
45 
46 static u32 ieee80211_idle_off(struct ieee80211_local *local,
47 			      const char *reason)
48 {
49 	if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
50 		return 0;
51 
52 	local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
53 	return IEEE80211_CONF_CHANGE_IDLE;
54 }
55 
56 static u32 ieee80211_idle_on(struct ieee80211_local *local)
57 {
58 	if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
59 		return 0;
60 
61 	drv_flush(local, false);
62 
63 	local->hw.conf.flags |= IEEE80211_CONF_IDLE;
64 	return IEEE80211_CONF_CHANGE_IDLE;
65 }
66 
67 static u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
68 {
69 	struct ieee80211_sub_if_data *sdata;
70 	int count = 0;
71 	bool working = false, scanning = false;
72 	unsigned int led_trig_start = 0, led_trig_stop = 0;
73 	struct ieee80211_roc_work *roc;
74 
75 #ifdef CONFIG_PROVE_LOCKING
76 	WARN_ON(debug_locks && !lockdep_rtnl_is_held() &&
77 		!lockdep_is_held(&local->iflist_mtx));
78 #endif
79 	lockdep_assert_held(&local->mtx);
80 
81 	list_for_each_entry(sdata, &local->interfaces, list) {
82 		if (!ieee80211_sdata_running(sdata)) {
83 			sdata->vif.bss_conf.idle = true;
84 			continue;
85 		}
86 
87 		sdata->old_idle = sdata->vif.bss_conf.idle;
88 
89 		/* do not count disabled managed interfaces */
90 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
91 		    !sdata->u.mgd.associated &&
92 		    !sdata->u.mgd.auth_data &&
93 		    !sdata->u.mgd.assoc_data) {
94 			sdata->vif.bss_conf.idle = true;
95 			continue;
96 		}
97 		/* do not count unused IBSS interfaces */
98 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
99 		    !sdata->u.ibss.ssid_len) {
100 			sdata->vif.bss_conf.idle = true;
101 			continue;
102 		}
103 		/* count everything else */
104 		sdata->vif.bss_conf.idle = false;
105 		count++;
106 	}
107 
108 	if (!local->ops->remain_on_channel) {
109 		list_for_each_entry(roc, &local->roc_list, list) {
110 			working = true;
111 			roc->sdata->vif.bss_conf.idle = false;
112 		}
113 	}
114 
115 	sdata = rcu_dereference_protected(local->scan_sdata,
116 					  lockdep_is_held(&local->mtx));
117 	if (sdata && !(local->hw.flags & IEEE80211_HW_SCAN_WHILE_IDLE)) {
118 		scanning = true;
119 		sdata->vif.bss_conf.idle = false;
120 	}
121 
122 	list_for_each_entry(sdata, &local->interfaces, list) {
123 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
124 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
125 			continue;
126 		if (sdata->old_idle == sdata->vif.bss_conf.idle)
127 			continue;
128 		if (!ieee80211_sdata_running(sdata))
129 			continue;
130 		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
131 	}
132 
133 	if (working || scanning)
134 		led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_WORK;
135 	else
136 		led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_WORK;
137 
138 	if (count)
139 		led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
140 	else
141 		led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
142 
143 	ieee80211_mod_tpt_led_trig(local, led_trig_start, led_trig_stop);
144 
145 	if (working)
146 		return ieee80211_idle_off(local, "working");
147 	if (scanning)
148 		return ieee80211_idle_off(local, "scanning");
149 	if (!count)
150 		return ieee80211_idle_on(local);
151 	else
152 		return ieee80211_idle_off(local, "in use");
153 
154 	return 0;
155 }
156 
157 void ieee80211_recalc_idle(struct ieee80211_local *local)
158 {
159 	u32 chg;
160 
161 	mutex_lock(&local->iflist_mtx);
162 	chg = __ieee80211_recalc_idle(local);
163 	mutex_unlock(&local->iflist_mtx);
164 	if (chg)
165 		ieee80211_hw_config(local, chg);
166 }
167 
168 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
169 {
170 	int meshhdrlen;
171 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
172 
173 	meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
174 
175 	/* FIX: what would be proper limits for MTU?
176 	 * This interface uses 802.3 frames. */
177 	if (new_mtu < 256 ||
178 	    new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
179 		return -EINVAL;
180 	}
181 
182 	dev->mtu = new_mtu;
183 	return 0;
184 }
185 
186 static int ieee80211_change_mac(struct net_device *dev, void *addr)
187 {
188 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
189 	struct sockaddr *sa = addr;
190 	int ret;
191 
192 	if (ieee80211_sdata_running(sdata))
193 		return -EBUSY;
194 
195 	ret = eth_mac_addr(dev, sa);
196 
197 	if (ret == 0)
198 		memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);
199 
200 	return ret;
201 }
202 
203 static inline int identical_mac_addr_allowed(int type1, int type2)
204 {
205 	return type1 == NL80211_IFTYPE_MONITOR ||
206 		type2 == NL80211_IFTYPE_MONITOR ||
207 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
208 		(type1 == NL80211_IFTYPE_WDS &&
209 			(type2 == NL80211_IFTYPE_WDS ||
210 			 type2 == NL80211_IFTYPE_AP)) ||
211 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
212 		(type1 == NL80211_IFTYPE_AP_VLAN &&
213 			(type2 == NL80211_IFTYPE_AP ||
214 			 type2 == NL80211_IFTYPE_AP_VLAN));
215 }
216 
217 static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
218 					    enum nl80211_iftype iftype)
219 {
220 	struct ieee80211_local *local = sdata->local;
221 	struct ieee80211_sub_if_data *nsdata;
222 
223 	ASSERT_RTNL();
224 
225 	/* we hold the RTNL here so can safely walk the list */
226 	list_for_each_entry(nsdata, &local->interfaces, list) {
227 		if (nsdata != sdata && ieee80211_sdata_running(nsdata)) {
228 			/*
229 			 * Allow only a single IBSS interface to be up at any
230 			 * time. This is restricted because beacon distribution
231 			 * cannot work properly if both are in the same IBSS.
232 			 *
233 			 * To remove this restriction we'd have to disallow them
234 			 * from setting the same SSID on different IBSS interfaces
235 			 * belonging to the same hardware. Then, however, we're
236 			 * faced with having to adopt two different TSF timers...
237 			 */
238 			if (iftype == NL80211_IFTYPE_ADHOC &&
239 			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
240 				return -EBUSY;
241 
242 			/*
243 			 * The remaining checks are only performed for interfaces
244 			 * with the same MAC address.
245 			 */
246 			if (!ether_addr_equal(sdata->vif.addr,
247 					      nsdata->vif.addr))
248 				continue;
249 
250 			/*
251 			 * check whether it may have the same address
252 			 */
253 			if (!identical_mac_addr_allowed(iftype,
254 							nsdata->vif.type))
255 				return -ENOTUNIQ;
256 
257 			/*
258 			 * can only add VLANs to enabled APs
259 			 */
260 			if (iftype == NL80211_IFTYPE_AP_VLAN &&
261 			    nsdata->vif.type == NL80211_IFTYPE_AP)
262 				sdata->bss = &nsdata->u.ap;
263 		}
264 	}
265 
266 	return 0;
267 }
268 
269 static int ieee80211_check_queues(struct ieee80211_sub_if_data *sdata)
270 {
271 	int n_queues = sdata->local->hw.queues;
272 	int i;
273 
274 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
275 		if (WARN_ON_ONCE(sdata->vif.hw_queue[i] ==
276 				 IEEE80211_INVAL_HW_QUEUE))
277 			return -EINVAL;
278 		if (WARN_ON_ONCE(sdata->vif.hw_queue[i] >=
279 				 n_queues))
280 			return -EINVAL;
281 	}
282 
283 	if ((sdata->vif.type != NL80211_IFTYPE_AP) ||
284 	    !(sdata->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)) {
285 		sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
286 		return 0;
287 	}
288 
289 	if (WARN_ON_ONCE(sdata->vif.cab_queue == IEEE80211_INVAL_HW_QUEUE))
290 		return -EINVAL;
291 
292 	if (WARN_ON_ONCE(sdata->vif.cab_queue >= n_queues))
293 		return -EINVAL;
294 
295 	return 0;
296 }
297 
298 void ieee80211_adjust_monitor_flags(struct ieee80211_sub_if_data *sdata,
299 				    const int offset)
300 {
301 	struct ieee80211_local *local = sdata->local;
302 	u32 flags = sdata->u.mntr_flags;
303 
304 #define ADJUST(_f, _s)	do {					\
305 	if (flags & MONITOR_FLAG_##_f)				\
306 		local->fif_##_s += offset;			\
307 	} while (0)
308 
309 	ADJUST(FCSFAIL, fcsfail);
310 	ADJUST(PLCPFAIL, plcpfail);
311 	ADJUST(CONTROL, control);
312 	ADJUST(CONTROL, pspoll);
313 	ADJUST(OTHER_BSS, other_bss);
314 
315 #undef ADJUST
316 }
317 
318 static void ieee80211_set_default_queues(struct ieee80211_sub_if_data *sdata)
319 {
320 	struct ieee80211_local *local = sdata->local;
321 	int i;
322 
323 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
324 		if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
325 			sdata->vif.hw_queue[i] = IEEE80211_INVAL_HW_QUEUE;
326 		else if (local->hw.queues >= IEEE80211_NUM_ACS)
327 			sdata->vif.hw_queue[i] = i;
328 		else
329 			sdata->vif.hw_queue[i] = 0;
330 	}
331 	sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
332 }
333 
334 static int ieee80211_add_virtual_monitor(struct ieee80211_local *local)
335 {
336 	struct ieee80211_sub_if_data *sdata;
337 	int ret = 0;
338 
339 	if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
340 		return 0;
341 
342 	mutex_lock(&local->iflist_mtx);
343 
344 	if (local->monitor_sdata)
345 		goto out_unlock;
346 
347 	sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size, GFP_KERNEL);
348 	if (!sdata) {
349 		ret = -ENOMEM;
350 		goto out_unlock;
351 	}
352 
353 	/* set up data */
354 	sdata->local = local;
355 	sdata->vif.type = NL80211_IFTYPE_MONITOR;
356 	snprintf(sdata->name, IFNAMSIZ, "%s-monitor",
357 		 wiphy_name(local->hw.wiphy));
358 
359 	ieee80211_set_default_queues(sdata);
360 
361 	ret = drv_add_interface(local, sdata);
362 	if (WARN_ON(ret)) {
363 		/* ok .. stupid driver, it asked for this! */
364 		kfree(sdata);
365 		goto out_unlock;
366 	}
367 
368 	ret = ieee80211_check_queues(sdata);
369 	if (ret) {
370 		kfree(sdata);
371 		goto out_unlock;
372 	}
373 
374 	rcu_assign_pointer(local->monitor_sdata, sdata);
375  out_unlock:
376 	mutex_unlock(&local->iflist_mtx);
377 	return ret;
378 }
379 
380 static void ieee80211_del_virtual_monitor(struct ieee80211_local *local)
381 {
382 	struct ieee80211_sub_if_data *sdata;
383 
384 	if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
385 		return;
386 
387 	mutex_lock(&local->iflist_mtx);
388 
389 	sdata = rcu_dereference_protected(local->monitor_sdata,
390 					  lockdep_is_held(&local->iflist_mtx));
391 	if (!sdata)
392 		goto out_unlock;
393 
394 	rcu_assign_pointer(local->monitor_sdata, NULL);
395 	synchronize_net();
396 
397 	drv_remove_interface(local, sdata);
398 
399 	kfree(sdata);
400  out_unlock:
401 	mutex_unlock(&local->iflist_mtx);
402 }
403 
404 /*
405  * NOTE: Be very careful when changing this function, it must NOT return
406  * an error on interface type changes that have been pre-checked, so most
407  * checks should be in ieee80211_check_concurrent_iface.
408  */
409 static int ieee80211_do_open(struct net_device *dev, bool coming_up)
410 {
411 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
412 	struct ieee80211_local *local = sdata->local;
413 	struct sta_info *sta;
414 	u32 changed = 0;
415 	int res;
416 	u32 hw_reconf_flags = 0;
417 
418 	switch (sdata->vif.type) {
419 	case NL80211_IFTYPE_WDS:
420 		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
421 			return -ENOLINK;
422 		break;
423 	case NL80211_IFTYPE_AP_VLAN: {
424 		struct ieee80211_sub_if_data *master;
425 
426 		if (!sdata->bss)
427 			return -ENOLINK;
428 
429 		list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
430 
431 		master = container_of(sdata->bss,
432 				      struct ieee80211_sub_if_data, u.ap);
433 		sdata->control_port_protocol =
434 			master->control_port_protocol;
435 		sdata->control_port_no_encrypt =
436 			master->control_port_no_encrypt;
437 		break;
438 		}
439 	case NL80211_IFTYPE_AP:
440 		sdata->bss = &sdata->u.ap;
441 		break;
442 	case NL80211_IFTYPE_MESH_POINT:
443 	case NL80211_IFTYPE_STATION:
444 	case NL80211_IFTYPE_MONITOR:
445 	case NL80211_IFTYPE_ADHOC:
446 		/* no special treatment */
447 		break;
448 	case NL80211_IFTYPE_UNSPECIFIED:
449 	case NUM_NL80211_IFTYPES:
450 	case NL80211_IFTYPE_P2P_CLIENT:
451 	case NL80211_IFTYPE_P2P_GO:
452 		/* cannot happen */
453 		WARN_ON(1);
454 		break;
455 	}
456 
457 	if (local->open_count == 0) {
458 		res = drv_start(local);
459 		if (res)
460 			goto err_del_bss;
461 		if (local->ops->napi_poll)
462 			napi_enable(&local->napi);
463 		/* we're brought up, everything changes */
464 		hw_reconf_flags = ~0;
465 		ieee80211_led_radio(local, true);
466 		ieee80211_mod_tpt_led_trig(local,
467 					   IEEE80211_TPT_LEDTRIG_FL_RADIO, 0);
468 	}
469 
470 	/*
471 	 * Copy the hopefully now-present MAC address to
472 	 * this interface, if it has the special null one.
473 	 */
474 	if (is_zero_ether_addr(dev->dev_addr)) {
475 		memcpy(dev->dev_addr,
476 		       local->hw.wiphy->perm_addr,
477 		       ETH_ALEN);
478 		memcpy(dev->perm_addr, dev->dev_addr, ETH_ALEN);
479 
480 		if (!is_valid_ether_addr(dev->dev_addr)) {
481 			res = -EADDRNOTAVAIL;
482 			goto err_stop;
483 		}
484 	}
485 
486 	switch (sdata->vif.type) {
487 	case NL80211_IFTYPE_AP_VLAN:
488 		/* no need to tell driver, but set carrier */
489 		if (rtnl_dereference(sdata->bss->beacon))
490 			netif_carrier_on(dev);
491 		else
492 			netif_carrier_off(dev);
493 		break;
494 	case NL80211_IFTYPE_MONITOR:
495 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
496 			local->cooked_mntrs++;
497 			break;
498 		}
499 
500 		if (local->monitors == 0 && local->open_count == 0) {
501 			res = ieee80211_add_virtual_monitor(local);
502 			if (res)
503 				goto err_stop;
504 		}
505 
506 		/* must be before the call to ieee80211_configure_filter */
507 		local->monitors++;
508 		if (local->monitors == 1) {
509 			local->hw.conf.flags |= IEEE80211_CONF_MONITOR;
510 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
511 		}
512 
513 		ieee80211_adjust_monitor_flags(sdata, 1);
514 		ieee80211_configure_filter(local);
515 
516 		netif_carrier_on(dev);
517 		break;
518 	default:
519 		if (coming_up) {
520 			ieee80211_del_virtual_monitor(local);
521 
522 			res = drv_add_interface(local, sdata);
523 			if (res)
524 				goto err_stop;
525 			res = ieee80211_check_queues(sdata);
526 			if (res)
527 				goto err_del_interface;
528 		}
529 
530 		if (sdata->vif.type == NL80211_IFTYPE_AP) {
531 			local->fif_pspoll++;
532 			local->fif_probe_req++;
533 
534 			ieee80211_configure_filter(local);
535 		} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
536 			local->fif_probe_req++;
537 		}
538 
539 		changed |= ieee80211_reset_erp_info(sdata);
540 		ieee80211_bss_info_change_notify(sdata, changed);
541 
542 		if (sdata->vif.type == NL80211_IFTYPE_STATION ||
543 		    sdata->vif.type == NL80211_IFTYPE_ADHOC ||
544 		    sdata->vif.type == NL80211_IFTYPE_AP)
545 			netif_carrier_off(dev);
546 		else
547 			netif_carrier_on(dev);
548 
549 		/*
550 		 * set default queue parameters so drivers don't
551 		 * need to initialise the hardware if the hardware
552 		 * doesn't start up with sane defaults
553 		 */
554 		ieee80211_set_wmm_default(sdata, true);
555 	}
556 
557 	set_bit(SDATA_STATE_RUNNING, &sdata->state);
558 
559 	if (sdata->vif.type == NL80211_IFTYPE_WDS) {
560 		/* Create STA entry for the WDS peer */
561 		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
562 				     GFP_KERNEL);
563 		if (!sta) {
564 			res = -ENOMEM;
565 			goto err_del_interface;
566 		}
567 
568 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
569 		sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
570 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
571 
572 		res = sta_info_insert(sta);
573 		if (res) {
574 			/* STA has been freed */
575 			goto err_del_interface;
576 		}
577 
578 		rate_control_rate_init(sta);
579 	}
580 
581 	/*
582 	 * set_multicast_list will be invoked by the networking core
583 	 * which will check whether any increments here were done in
584 	 * error and sync them down to the hardware as filter flags.
585 	 */
586 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
587 		atomic_inc(&local->iff_allmultis);
588 
589 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
590 		atomic_inc(&local->iff_promiscs);
591 
592 	mutex_lock(&local->mtx);
593 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
594 	mutex_unlock(&local->mtx);
595 
596 	if (coming_up)
597 		local->open_count++;
598 
599 	if (hw_reconf_flags)
600 		ieee80211_hw_config(local, hw_reconf_flags);
601 
602 	ieee80211_recalc_ps(local, -1);
603 
604 	netif_tx_start_all_queues(dev);
605 
606 	return 0;
607  err_del_interface:
608 	drv_remove_interface(local, sdata);
609  err_stop:
610 	if (!local->open_count)
611 		drv_stop(local);
612  err_del_bss:
613 	sdata->bss = NULL;
614 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
615 		list_del(&sdata->u.vlan.list);
616 	/* might already be clear but that doesn't matter */
617 	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
618 	return res;
619 }
620 
621 static int ieee80211_open(struct net_device *dev)
622 {
623 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
624 	int err;
625 
626 	/* fail early if user set an invalid address */
627 	if (!is_valid_ether_addr(dev->dev_addr))
628 		return -EADDRNOTAVAIL;
629 
630 	err = ieee80211_check_concurrent_iface(sdata, sdata->vif.type);
631 	if (err)
632 		return err;
633 
634 	return ieee80211_do_open(dev, true);
635 }
636 
637 static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
638 			      bool going_down)
639 {
640 	struct ieee80211_local *local = sdata->local;
641 	unsigned long flags;
642 	struct sk_buff *skb, *tmp;
643 	u32 hw_reconf_flags = 0;
644 	int i;
645 	enum nl80211_channel_type orig_ct;
646 
647 	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
648 
649 	if (rcu_access_pointer(local->scan_sdata) == sdata)
650 		ieee80211_scan_cancel(local);
651 
652 	/*
653 	 * Stop TX on this interface first.
654 	 */
655 	netif_tx_stop_all_queues(sdata->dev);
656 
657 	ieee80211_roc_purge(sdata);
658 
659 	/*
660 	 * Remove all stations associated with this interface.
661 	 *
662 	 * This must be done before calling ops->remove_interface()
663 	 * because otherwise we can later invoke ops->sta_notify()
664 	 * whenever the STAs are removed, and that invalidates driver
665 	 * assumptions about always getting a vif pointer that is valid
666 	 * (because if we remove a STA after ops->remove_interface()
667 	 * the driver will have removed the vif info already!)
668 	 *
669 	 * This is relevant only in AP, WDS and mesh modes, since in
670 	 * all other modes we've already removed all stations when
671 	 * disconnecting etc.
672 	 */
673 	sta_info_flush(local, sdata);
674 
675 	/*
676 	 * Don't count this interface for promisc/allmulti while it
677 	 * is down. dev_mc_unsync() will invoke set_multicast_list
678 	 * on the master interface which will sync these down to the
679 	 * hardware as filter flags.
680 	 */
681 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
682 		atomic_dec(&local->iff_allmultis);
683 
684 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
685 		atomic_dec(&local->iff_promiscs);
686 
687 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
688 		local->fif_pspoll--;
689 		local->fif_probe_req--;
690 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
691 		local->fif_probe_req--;
692 	}
693 
694 	netif_addr_lock_bh(sdata->dev);
695 	spin_lock_bh(&local->filter_lock);
696 	__hw_addr_unsync(&local->mc_list, &sdata->dev->mc,
697 			 sdata->dev->addr_len);
698 	spin_unlock_bh(&local->filter_lock);
699 	netif_addr_unlock_bh(sdata->dev);
700 
701 	ieee80211_configure_filter(local);
702 
703 	del_timer_sync(&local->dynamic_ps_timer);
704 	cancel_work_sync(&local->dynamic_ps_enable_work);
705 
706 	/* APs need special treatment */
707 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
708 		struct ieee80211_sub_if_data *vlan, *tmpsdata;
709 		struct beacon_data *old_beacon =
710 			rtnl_dereference(sdata->u.ap.beacon);
711 		struct sk_buff *old_probe_resp =
712 			rtnl_dereference(sdata->u.ap.probe_resp);
713 
714 		/* sdata_running will return false, so this will disable */
715 		ieee80211_bss_info_change_notify(sdata,
716 						 BSS_CHANGED_BEACON_ENABLED);
717 
718 		/* remove beacon and probe response */
719 		RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
720 		RCU_INIT_POINTER(sdata->u.ap.probe_resp, NULL);
721 		synchronize_rcu();
722 		kfree(old_beacon);
723 		kfree_skb(old_probe_resp);
724 
725 		/* down all dependent devices, that is VLANs */
726 		list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
727 					 u.vlan.list)
728 			dev_close(vlan->dev);
729 		WARN_ON(!list_empty(&sdata->u.ap.vlans));
730 
731 		/* free all potentially still buffered bcast frames */
732 		local->total_ps_buffered -= skb_queue_len(&sdata->u.ap.ps_bc_buf);
733 		skb_queue_purge(&sdata->u.ap.ps_bc_buf);
734 	} else if (sdata->vif.type == NL80211_IFTYPE_STATION) {
735 		ieee80211_mgd_stop(sdata);
736 	}
737 
738 	if (going_down)
739 		local->open_count--;
740 
741 	switch (sdata->vif.type) {
742 	case NL80211_IFTYPE_AP_VLAN:
743 		list_del(&sdata->u.vlan.list);
744 		/* no need to tell driver */
745 		break;
746 	case NL80211_IFTYPE_MONITOR:
747 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
748 			local->cooked_mntrs--;
749 			break;
750 		}
751 
752 		local->monitors--;
753 		if (local->monitors == 0) {
754 			local->hw.conf.flags &= ~IEEE80211_CONF_MONITOR;
755 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
756 			ieee80211_del_virtual_monitor(local);
757 		}
758 
759 		ieee80211_adjust_monitor_flags(sdata, -1);
760 		ieee80211_configure_filter(local);
761 		break;
762 	default:
763 		flush_work(&sdata->work);
764 		/*
765 		 * When we get here, the interface is marked down.
766 		 * Call synchronize_rcu() to wait for the RX path
767 		 * should it be using the interface and enqueuing
768 		 * frames at this very time on another CPU.
769 		 */
770 		synchronize_rcu();
771 		skb_queue_purge(&sdata->skb_queue);
772 
773 		/*
774 		 * Disable beaconing here for mesh only, AP and IBSS
775 		 * are already taken care of.
776 		 */
777 		if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
778 			ieee80211_bss_info_change_notify(sdata,
779 				BSS_CHANGED_BEACON_ENABLED);
780 
781 		/*
782 		 * Free all remaining keys, there shouldn't be any,
783 		 * except maybe group keys in AP more or WDS?
784 		 */
785 		ieee80211_free_keys(sdata);
786 
787 		if (going_down)
788 			drv_remove_interface(local, sdata);
789 	}
790 
791 	sdata->bss = NULL;
792 
793 	mutex_lock(&local->mtx);
794 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
795 	mutex_unlock(&local->mtx);
796 
797 	ieee80211_recalc_ps(local, -1);
798 
799 	if (local->open_count == 0) {
800 		if (local->ops->napi_poll)
801 			napi_disable(&local->napi);
802 		ieee80211_clear_tx_pending(local);
803 		ieee80211_stop_device(local);
804 
805 		/* no reconfiguring after stop! */
806 		hw_reconf_flags = 0;
807 	}
808 
809 	/* Re-calculate channel-type, in case there are multiple vifs
810 	 * on different channel types.
811 	 */
812 	orig_ct = local->_oper_channel_type;
813 	ieee80211_set_channel_type(local, NULL, NL80211_CHAN_NO_HT);
814 
815 	/* do after stop to avoid reconfiguring when we stop anyway */
816 	if (hw_reconf_flags || (orig_ct != local->_oper_channel_type))
817 		ieee80211_hw_config(local, hw_reconf_flags);
818 
819 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
820 	for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
821 		skb_queue_walk_safe(&local->pending[i], skb, tmp) {
822 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
823 			if (info->control.vif == &sdata->vif) {
824 				__skb_unlink(skb, &local->pending[i]);
825 				dev_kfree_skb_irq(skb);
826 			}
827 		}
828 	}
829 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
830 
831 	if (local->monitors == local->open_count && local->monitors > 0)
832 		ieee80211_add_virtual_monitor(local);
833 }
834 
835 static int ieee80211_stop(struct net_device *dev)
836 {
837 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
838 
839 	ieee80211_do_stop(sdata, true);
840 
841 	return 0;
842 }
843 
844 static void ieee80211_set_multicast_list(struct net_device *dev)
845 {
846 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
847 	struct ieee80211_local *local = sdata->local;
848 	int allmulti, promisc, sdata_allmulti, sdata_promisc;
849 
850 	allmulti = !!(dev->flags & IFF_ALLMULTI);
851 	promisc = !!(dev->flags & IFF_PROMISC);
852 	sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
853 	sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
854 
855 	if (allmulti != sdata_allmulti) {
856 		if (dev->flags & IFF_ALLMULTI)
857 			atomic_inc(&local->iff_allmultis);
858 		else
859 			atomic_dec(&local->iff_allmultis);
860 		sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
861 	}
862 
863 	if (promisc != sdata_promisc) {
864 		if (dev->flags & IFF_PROMISC)
865 			atomic_inc(&local->iff_promiscs);
866 		else
867 			atomic_dec(&local->iff_promiscs);
868 		sdata->flags ^= IEEE80211_SDATA_PROMISC;
869 	}
870 	spin_lock_bh(&local->filter_lock);
871 	__hw_addr_sync(&local->mc_list, &dev->mc, dev->addr_len);
872 	spin_unlock_bh(&local->filter_lock);
873 	ieee80211_queue_work(&local->hw, &local->reconfig_filter);
874 }
875 
876 /*
877  * Called when the netdev is removed or, by the code below, before
878  * the interface type changes.
879  */
880 static void ieee80211_teardown_sdata(struct net_device *dev)
881 {
882 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
883 	struct ieee80211_local *local = sdata->local;
884 	int flushed;
885 	int i;
886 
887 	/* free extra data */
888 	ieee80211_free_keys(sdata);
889 
890 	ieee80211_debugfs_remove_netdev(sdata);
891 
892 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
893 		__skb_queue_purge(&sdata->fragments[i].skb_list);
894 	sdata->fragment_next = 0;
895 
896 	if (ieee80211_vif_is_mesh(&sdata->vif))
897 		mesh_rmc_free(sdata);
898 
899 	flushed = sta_info_flush(local, sdata);
900 	WARN_ON(flushed);
901 }
902 
903 static u16 ieee80211_netdev_select_queue(struct net_device *dev,
904 					 struct sk_buff *skb)
905 {
906 	return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb);
907 }
908 
909 static const struct net_device_ops ieee80211_dataif_ops = {
910 	.ndo_open		= ieee80211_open,
911 	.ndo_stop		= ieee80211_stop,
912 	.ndo_uninit		= ieee80211_teardown_sdata,
913 	.ndo_start_xmit		= ieee80211_subif_start_xmit,
914 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
915 	.ndo_change_mtu 	= ieee80211_change_mtu,
916 	.ndo_set_mac_address 	= ieee80211_change_mac,
917 	.ndo_select_queue	= ieee80211_netdev_select_queue,
918 };
919 
920 static u16 ieee80211_monitor_select_queue(struct net_device *dev,
921 					  struct sk_buff *skb)
922 {
923 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
924 	struct ieee80211_local *local = sdata->local;
925 	struct ieee80211_hdr *hdr;
926 	struct ieee80211_radiotap_header *rtap = (void *)skb->data;
927 
928 	if (local->hw.queues < IEEE80211_NUM_ACS)
929 		return 0;
930 
931 	if (skb->len < 4 ||
932 	    skb->len < le16_to_cpu(rtap->it_len) + 2 /* frame control */)
933 		return 0; /* doesn't matter, frame will be dropped */
934 
935 	hdr = (void *)((u8 *)skb->data + le16_to_cpu(rtap->it_len));
936 
937 	return ieee80211_select_queue_80211(sdata, skb, hdr);
938 }
939 
940 static const struct net_device_ops ieee80211_monitorif_ops = {
941 	.ndo_open		= ieee80211_open,
942 	.ndo_stop		= ieee80211_stop,
943 	.ndo_uninit		= ieee80211_teardown_sdata,
944 	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
945 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
946 	.ndo_change_mtu 	= ieee80211_change_mtu,
947 	.ndo_set_mac_address 	= eth_mac_addr,
948 	.ndo_select_queue	= ieee80211_monitor_select_queue,
949 };
950 
951 static void ieee80211_if_setup(struct net_device *dev)
952 {
953 	ether_setup(dev);
954 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
955 	dev->netdev_ops = &ieee80211_dataif_ops;
956 	dev->destructor = free_netdev;
957 }
958 
959 static void ieee80211_iface_work(struct work_struct *work)
960 {
961 	struct ieee80211_sub_if_data *sdata =
962 		container_of(work, struct ieee80211_sub_if_data, work);
963 	struct ieee80211_local *local = sdata->local;
964 	struct sk_buff *skb;
965 	struct sta_info *sta;
966 	struct ieee80211_ra_tid *ra_tid;
967 
968 	if (!ieee80211_sdata_running(sdata))
969 		return;
970 
971 	if (local->scanning)
972 		return;
973 
974 	/*
975 	 * ieee80211_queue_work() should have picked up most cases,
976 	 * here we'll pick the rest.
977 	 */
978 	if (WARN(local->suspended,
979 		 "interface work scheduled while going to suspend\n"))
980 		return;
981 
982 	/* first process frames */
983 	while ((skb = skb_dequeue(&sdata->skb_queue))) {
984 		struct ieee80211_mgmt *mgmt = (void *)skb->data;
985 
986 		if (skb->pkt_type == IEEE80211_SDATA_QUEUE_AGG_START) {
987 			ra_tid = (void *)&skb->cb;
988 			ieee80211_start_tx_ba_cb(&sdata->vif, ra_tid->ra,
989 						 ra_tid->tid);
990 		} else if (skb->pkt_type == IEEE80211_SDATA_QUEUE_AGG_STOP) {
991 			ra_tid = (void *)&skb->cb;
992 			ieee80211_stop_tx_ba_cb(&sdata->vif, ra_tid->ra,
993 						ra_tid->tid);
994 		} else if (ieee80211_is_action(mgmt->frame_control) &&
995 			   mgmt->u.action.category == WLAN_CATEGORY_BACK) {
996 			int len = skb->len;
997 
998 			mutex_lock(&local->sta_mtx);
999 			sta = sta_info_get_bss(sdata, mgmt->sa);
1000 			if (sta) {
1001 				switch (mgmt->u.action.u.addba_req.action_code) {
1002 				case WLAN_ACTION_ADDBA_REQ:
1003 					ieee80211_process_addba_request(
1004 							local, sta, mgmt, len);
1005 					break;
1006 				case WLAN_ACTION_ADDBA_RESP:
1007 					ieee80211_process_addba_resp(local, sta,
1008 								     mgmt, len);
1009 					break;
1010 				case WLAN_ACTION_DELBA:
1011 					ieee80211_process_delba(sdata, sta,
1012 								mgmt, len);
1013 					break;
1014 				default:
1015 					WARN_ON(1);
1016 					break;
1017 				}
1018 			}
1019 			mutex_unlock(&local->sta_mtx);
1020 		} else if (ieee80211_is_data_qos(mgmt->frame_control)) {
1021 			struct ieee80211_hdr *hdr = (void *)mgmt;
1022 			/*
1023 			 * So the frame isn't mgmt, but frame_control
1024 			 * is at the right place anyway, of course, so
1025 			 * the if statement is correct.
1026 			 *
1027 			 * Warn if we have other data frame types here,
1028 			 * they must not get here.
1029 			 */
1030 			WARN_ON(hdr->frame_control &
1031 					cpu_to_le16(IEEE80211_STYPE_NULLFUNC));
1032 			WARN_ON(!(hdr->seq_ctrl &
1033 					cpu_to_le16(IEEE80211_SCTL_FRAG)));
1034 			/*
1035 			 * This was a fragment of a frame, received while
1036 			 * a block-ack session was active. That cannot be
1037 			 * right, so terminate the session.
1038 			 */
1039 			mutex_lock(&local->sta_mtx);
1040 			sta = sta_info_get_bss(sdata, mgmt->sa);
1041 			if (sta) {
1042 				u16 tid = *ieee80211_get_qos_ctl(hdr) &
1043 						IEEE80211_QOS_CTL_TID_MASK;
1044 
1045 				__ieee80211_stop_rx_ba_session(
1046 					sta, tid, WLAN_BACK_RECIPIENT,
1047 					WLAN_REASON_QSTA_REQUIRE_SETUP,
1048 					true);
1049 			}
1050 			mutex_unlock(&local->sta_mtx);
1051 		} else switch (sdata->vif.type) {
1052 		case NL80211_IFTYPE_STATION:
1053 			ieee80211_sta_rx_queued_mgmt(sdata, skb);
1054 			break;
1055 		case NL80211_IFTYPE_ADHOC:
1056 			ieee80211_ibss_rx_queued_mgmt(sdata, skb);
1057 			break;
1058 		case NL80211_IFTYPE_MESH_POINT:
1059 			if (!ieee80211_vif_is_mesh(&sdata->vif))
1060 				break;
1061 			ieee80211_mesh_rx_queued_mgmt(sdata, skb);
1062 			break;
1063 		default:
1064 			WARN(1, "frame for unexpected interface type");
1065 			break;
1066 		}
1067 
1068 		kfree_skb(skb);
1069 	}
1070 
1071 	/* then other type-dependent work */
1072 	switch (sdata->vif.type) {
1073 	case NL80211_IFTYPE_STATION:
1074 		ieee80211_sta_work(sdata);
1075 		break;
1076 	case NL80211_IFTYPE_ADHOC:
1077 		ieee80211_ibss_work(sdata);
1078 		break;
1079 	case NL80211_IFTYPE_MESH_POINT:
1080 		if (!ieee80211_vif_is_mesh(&sdata->vif))
1081 			break;
1082 		ieee80211_mesh_work(sdata);
1083 		break;
1084 	default:
1085 		break;
1086 	}
1087 }
1088 
1089 
1090 /*
1091  * Helper function to initialise an interface to a specific type.
1092  */
1093 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
1094 				  enum nl80211_iftype type)
1095 {
1096 	/* clear type-dependent union */
1097 	memset(&sdata->u, 0, sizeof(sdata->u));
1098 
1099 	/* and set some type-dependent values */
1100 	sdata->vif.type = type;
1101 	sdata->vif.p2p = false;
1102 	sdata->dev->netdev_ops = &ieee80211_dataif_ops;
1103 	sdata->wdev.iftype = type;
1104 
1105 	sdata->control_port_protocol = cpu_to_be16(ETH_P_PAE);
1106 	sdata->control_port_no_encrypt = false;
1107 
1108 	sdata->noack_map = 0;
1109 
1110 	/* only monitor differs */
1111 	sdata->dev->type = ARPHRD_ETHER;
1112 
1113 	skb_queue_head_init(&sdata->skb_queue);
1114 	INIT_WORK(&sdata->work, ieee80211_iface_work);
1115 
1116 	switch (type) {
1117 	case NL80211_IFTYPE_P2P_GO:
1118 		type = NL80211_IFTYPE_AP;
1119 		sdata->vif.type = type;
1120 		sdata->vif.p2p = true;
1121 		/* fall through */
1122 	case NL80211_IFTYPE_AP:
1123 		skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
1124 		INIT_LIST_HEAD(&sdata->u.ap.vlans);
1125 		break;
1126 	case NL80211_IFTYPE_P2P_CLIENT:
1127 		type = NL80211_IFTYPE_STATION;
1128 		sdata->vif.type = type;
1129 		sdata->vif.p2p = true;
1130 		/* fall through */
1131 	case NL80211_IFTYPE_STATION:
1132 		ieee80211_sta_setup_sdata(sdata);
1133 		break;
1134 	case NL80211_IFTYPE_ADHOC:
1135 		ieee80211_ibss_setup_sdata(sdata);
1136 		break;
1137 	case NL80211_IFTYPE_MESH_POINT:
1138 		if (ieee80211_vif_is_mesh(&sdata->vif))
1139 			ieee80211_mesh_init_sdata(sdata);
1140 		break;
1141 	case NL80211_IFTYPE_MONITOR:
1142 		sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
1143 		sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
1144 		sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
1145 				      MONITOR_FLAG_OTHER_BSS;
1146 		break;
1147 	case NL80211_IFTYPE_WDS:
1148 	case NL80211_IFTYPE_AP_VLAN:
1149 		break;
1150 	case NL80211_IFTYPE_UNSPECIFIED:
1151 	case NUM_NL80211_IFTYPES:
1152 		BUG();
1153 		break;
1154 	}
1155 
1156 	ieee80211_debugfs_add_netdev(sdata);
1157 }
1158 
1159 static void ieee80211_clean_sdata(struct ieee80211_sub_if_data *sdata)
1160 {
1161 	switch (sdata->vif.type) {
1162 	case NL80211_IFTYPE_MESH_POINT:
1163 		mesh_path_flush_by_iface(sdata);
1164 		break;
1165 
1166 	default:
1167 		break;
1168 	}
1169 }
1170 
1171 static int ieee80211_runtime_change_iftype(struct ieee80211_sub_if_data *sdata,
1172 					   enum nl80211_iftype type)
1173 {
1174 	struct ieee80211_local *local = sdata->local;
1175 	int ret, err;
1176 	enum nl80211_iftype internal_type = type;
1177 	bool p2p = false;
1178 
1179 	ASSERT_RTNL();
1180 
1181 	if (!local->ops->change_interface)
1182 		return -EBUSY;
1183 
1184 	switch (sdata->vif.type) {
1185 	case NL80211_IFTYPE_AP:
1186 	case NL80211_IFTYPE_STATION:
1187 	case NL80211_IFTYPE_ADHOC:
1188 		/*
1189 		 * Could maybe also all others here?
1190 		 * Just not sure how that interacts
1191 		 * with the RX/config path e.g. for
1192 		 * mesh.
1193 		 */
1194 		break;
1195 	default:
1196 		return -EBUSY;
1197 	}
1198 
1199 	switch (type) {
1200 	case NL80211_IFTYPE_AP:
1201 	case NL80211_IFTYPE_STATION:
1202 	case NL80211_IFTYPE_ADHOC:
1203 		/*
1204 		 * Could probably support everything
1205 		 * but WDS here (WDS do_open can fail
1206 		 * under memory pressure, which this
1207 		 * code isn't prepared to handle).
1208 		 */
1209 		break;
1210 	case NL80211_IFTYPE_P2P_CLIENT:
1211 		p2p = true;
1212 		internal_type = NL80211_IFTYPE_STATION;
1213 		break;
1214 	case NL80211_IFTYPE_P2P_GO:
1215 		p2p = true;
1216 		internal_type = NL80211_IFTYPE_AP;
1217 		break;
1218 	default:
1219 		return -EBUSY;
1220 	}
1221 
1222 	ret = ieee80211_check_concurrent_iface(sdata, internal_type);
1223 	if (ret)
1224 		return ret;
1225 
1226 	ieee80211_do_stop(sdata, false);
1227 
1228 	ieee80211_teardown_sdata(sdata->dev);
1229 
1230 	ret = drv_change_interface(local, sdata, internal_type, p2p);
1231 	if (ret)
1232 		type = sdata->vif.type;
1233 
1234 	/*
1235 	 * Ignore return value here, there's not much we can do since
1236 	 * the driver changed the interface type internally already.
1237 	 * The warnings will hopefully make driver authors fix it :-)
1238 	 */
1239 	ieee80211_check_queues(sdata);
1240 
1241 	ieee80211_setup_sdata(sdata, type);
1242 
1243 	err = ieee80211_do_open(sdata->dev, false);
1244 	WARN(err, "type change: do_open returned %d", err);
1245 
1246 	return ret;
1247 }
1248 
1249 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
1250 			     enum nl80211_iftype type)
1251 {
1252 	int ret;
1253 
1254 	ASSERT_RTNL();
1255 
1256 	if (type == ieee80211_vif_type_p2p(&sdata->vif))
1257 		return 0;
1258 
1259 	/* Setting ad-hoc mode on non-IBSS channel is not supported. */
1260 	if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
1261 	    type == NL80211_IFTYPE_ADHOC)
1262 		return -EOPNOTSUPP;
1263 
1264 	if (ieee80211_sdata_running(sdata)) {
1265 		ret = ieee80211_runtime_change_iftype(sdata, type);
1266 		if (ret)
1267 			return ret;
1268 	} else {
1269 		/* Purge and reset type-dependent state. */
1270 		ieee80211_teardown_sdata(sdata->dev);
1271 		ieee80211_setup_sdata(sdata, type);
1272 	}
1273 
1274 	/* reset some values that shouldn't be kept across type changes */
1275 	sdata->vif.bss_conf.basic_rates =
1276 		ieee80211_mandatory_rates(sdata->local,
1277 			sdata->local->hw.conf.channel->band);
1278 	sdata->drop_unencrypted = 0;
1279 	if (type == NL80211_IFTYPE_STATION)
1280 		sdata->u.mgd.use_4addr = false;
1281 
1282 	return 0;
1283 }
1284 
1285 static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
1286 				       struct net_device *dev,
1287 				       enum nl80211_iftype type)
1288 {
1289 	struct ieee80211_sub_if_data *sdata;
1290 	u64 mask, start, addr, val, inc;
1291 	u8 *m;
1292 	u8 tmp_addr[ETH_ALEN];
1293 	int i;
1294 
1295 	/* default ... something at least */
1296 	memcpy(dev->perm_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
1297 
1298 	if (is_zero_ether_addr(local->hw.wiphy->addr_mask) &&
1299 	    local->hw.wiphy->n_addresses <= 1)
1300 		return;
1301 
1302 
1303 	mutex_lock(&local->iflist_mtx);
1304 
1305 	switch (type) {
1306 	case NL80211_IFTYPE_MONITOR:
1307 		/* doesn't matter */
1308 		break;
1309 	case NL80211_IFTYPE_WDS:
1310 	case NL80211_IFTYPE_AP_VLAN:
1311 		/* match up with an AP interface */
1312 		list_for_each_entry(sdata, &local->interfaces, list) {
1313 			if (sdata->vif.type != NL80211_IFTYPE_AP)
1314 				continue;
1315 			memcpy(dev->perm_addr, sdata->vif.addr, ETH_ALEN);
1316 			break;
1317 		}
1318 		/* keep default if no AP interface present */
1319 		break;
1320 	default:
1321 		/* assign a new address if possible -- try n_addresses first */
1322 		for (i = 0; i < local->hw.wiphy->n_addresses; i++) {
1323 			bool used = false;
1324 
1325 			list_for_each_entry(sdata, &local->interfaces, list) {
1326 				if (memcmp(local->hw.wiphy->addresses[i].addr,
1327 					   sdata->vif.addr, ETH_ALEN) == 0) {
1328 					used = true;
1329 					break;
1330 				}
1331 			}
1332 
1333 			if (!used) {
1334 				memcpy(dev->perm_addr,
1335 				       local->hw.wiphy->addresses[i].addr,
1336 				       ETH_ALEN);
1337 				break;
1338 			}
1339 		}
1340 
1341 		/* try mask if available */
1342 		if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
1343 			break;
1344 
1345 		m = local->hw.wiphy->addr_mask;
1346 		mask =	((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
1347 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
1348 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
1349 
1350 		if (__ffs64(mask) + hweight64(mask) != fls64(mask)) {
1351 			/* not a contiguous mask ... not handled now! */
1352 			pr_info("not contiguous\n");
1353 			break;
1354 		}
1355 
1356 		m = local->hw.wiphy->perm_addr;
1357 		start = ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
1358 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
1359 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
1360 
1361 		inc = 1ULL<<__ffs64(mask);
1362 		val = (start & mask);
1363 		addr = (start & ~mask) | (val & mask);
1364 		do {
1365 			bool used = false;
1366 
1367 			tmp_addr[5] = addr >> 0*8;
1368 			tmp_addr[4] = addr >> 1*8;
1369 			tmp_addr[3] = addr >> 2*8;
1370 			tmp_addr[2] = addr >> 3*8;
1371 			tmp_addr[1] = addr >> 4*8;
1372 			tmp_addr[0] = addr >> 5*8;
1373 
1374 			val += inc;
1375 
1376 			list_for_each_entry(sdata, &local->interfaces, list) {
1377 				if (memcmp(tmp_addr, sdata->vif.addr,
1378 							ETH_ALEN) == 0) {
1379 					used = true;
1380 					break;
1381 				}
1382 			}
1383 
1384 			if (!used) {
1385 				memcpy(dev->perm_addr, tmp_addr, ETH_ALEN);
1386 				break;
1387 			}
1388 			addr = (start & ~mask) | (val & mask);
1389 		} while (addr != start);
1390 
1391 		break;
1392 	}
1393 
1394 	mutex_unlock(&local->iflist_mtx);
1395 }
1396 
1397 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
1398 		     struct wireless_dev **new_wdev, enum nl80211_iftype type,
1399 		     struct vif_params *params)
1400 {
1401 	struct net_device *ndev;
1402 	struct ieee80211_sub_if_data *sdata = NULL;
1403 	int ret, i;
1404 	int txqs = 1;
1405 
1406 	ASSERT_RTNL();
1407 
1408 	if (local->hw.queues >= IEEE80211_NUM_ACS)
1409 		txqs = IEEE80211_NUM_ACS;
1410 
1411 	ndev = alloc_netdev_mqs(sizeof(*sdata) + local->hw.vif_data_size,
1412 				name, ieee80211_if_setup, txqs, 1);
1413 	if (!ndev)
1414 		return -ENOMEM;
1415 	dev_net_set(ndev, wiphy_net(local->hw.wiphy));
1416 
1417 	ndev->needed_headroom = local->tx_headroom +
1418 				4*6 /* four MAC addresses */
1419 				+ 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
1420 				+ 6 /* mesh */
1421 				+ 8 /* rfc1042/bridge tunnel */
1422 				- ETH_HLEN /* ethernet hard_header_len */
1423 				+ IEEE80211_ENCRYPT_HEADROOM;
1424 	ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
1425 
1426 	ret = dev_alloc_name(ndev, ndev->name);
1427 	if (ret < 0)
1428 		goto fail;
1429 
1430 	ieee80211_assign_perm_addr(local, ndev, type);
1431 	memcpy(ndev->dev_addr, ndev->perm_addr, ETH_ALEN);
1432 	SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
1433 
1434 	/* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
1435 	sdata = netdev_priv(ndev);
1436 	ndev->ieee80211_ptr = &sdata->wdev;
1437 	memcpy(sdata->vif.addr, ndev->dev_addr, ETH_ALEN);
1438 	memcpy(sdata->name, ndev->name, IFNAMSIZ);
1439 
1440 	/* initialise type-independent data */
1441 	sdata->wdev.wiphy = local->hw.wiphy;
1442 	sdata->local = local;
1443 	sdata->dev = ndev;
1444 #ifdef CONFIG_INET
1445 	sdata->arp_filter_state = true;
1446 #endif
1447 
1448 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
1449 		skb_queue_head_init(&sdata->fragments[i].skb_list);
1450 
1451 	INIT_LIST_HEAD(&sdata->key_list);
1452 
1453 	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
1454 		struct ieee80211_supported_band *sband;
1455 		sband = local->hw.wiphy->bands[i];
1456 		sdata->rc_rateidx_mask[i] =
1457 			sband ? (1 << sband->n_bitrates) - 1 : 0;
1458 		if (sband)
1459 			memcpy(sdata->rc_rateidx_mcs_mask[i],
1460 			       sband->ht_cap.mcs.rx_mask,
1461 			       sizeof(sdata->rc_rateidx_mcs_mask[i]));
1462 		else
1463 			memset(sdata->rc_rateidx_mcs_mask[i], 0,
1464 			       sizeof(sdata->rc_rateidx_mcs_mask[i]));
1465 	}
1466 
1467 	ieee80211_set_default_queues(sdata);
1468 
1469 	/* setup type-dependent data */
1470 	ieee80211_setup_sdata(sdata, type);
1471 
1472 	if (params) {
1473 		ndev->ieee80211_ptr->use_4addr = params->use_4addr;
1474 		if (type == NL80211_IFTYPE_STATION)
1475 			sdata->u.mgd.use_4addr = params->use_4addr;
1476 	}
1477 
1478 	ndev->features |= local->hw.netdev_features;
1479 
1480 	ret = register_netdevice(ndev);
1481 	if (ret)
1482 		goto fail;
1483 
1484 	mutex_lock(&local->iflist_mtx);
1485 	list_add_tail_rcu(&sdata->list, &local->interfaces);
1486 	mutex_unlock(&local->iflist_mtx);
1487 
1488 	if (new_wdev)
1489 		*new_wdev = &sdata->wdev;
1490 
1491 	return 0;
1492 
1493  fail:
1494 	free_netdev(ndev);
1495 	return ret;
1496 }
1497 
1498 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
1499 {
1500 	ASSERT_RTNL();
1501 
1502 	mutex_lock(&sdata->local->iflist_mtx);
1503 	list_del_rcu(&sdata->list);
1504 	mutex_unlock(&sdata->local->iflist_mtx);
1505 
1506 	/* clean up type-dependent data */
1507 	ieee80211_clean_sdata(sdata);
1508 
1509 	synchronize_rcu();
1510 	unregister_netdevice(sdata->dev);
1511 }
1512 
1513 /*
1514  * Remove all interfaces, may only be called at hardware unregistration
1515  * time because it doesn't do RCU-safe list removals.
1516  */
1517 void ieee80211_remove_interfaces(struct ieee80211_local *local)
1518 {
1519 	struct ieee80211_sub_if_data *sdata, *tmp;
1520 	LIST_HEAD(unreg_list);
1521 
1522 	ASSERT_RTNL();
1523 
1524 	mutex_lock(&local->iflist_mtx);
1525 	list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
1526 		list_del(&sdata->list);
1527 
1528 		ieee80211_clean_sdata(sdata);
1529 
1530 		unregister_netdevice_queue(sdata->dev, &unreg_list);
1531 	}
1532 	mutex_unlock(&local->iflist_mtx);
1533 	unregister_netdevice_many(&unreg_list);
1534 	list_del(&unreg_list);
1535 }
1536 
1537 static int netdev_notify(struct notifier_block *nb,
1538 			 unsigned long state,
1539 			 void *ndev)
1540 {
1541 	struct net_device *dev = ndev;
1542 	struct ieee80211_sub_if_data *sdata;
1543 
1544 	if (state != NETDEV_CHANGENAME)
1545 		return 0;
1546 
1547 	if (!dev->ieee80211_ptr || !dev->ieee80211_ptr->wiphy)
1548 		return 0;
1549 
1550 	if (dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
1551 		return 0;
1552 
1553 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1554 
1555 	memcpy(sdata->name, dev->name, IFNAMSIZ);
1556 
1557 	ieee80211_debugfs_rename_netdev(sdata);
1558 	return 0;
1559 }
1560 
1561 static struct notifier_block mac80211_netdev_notifier = {
1562 	.notifier_call = netdev_notify,
1563 };
1564 
1565 int ieee80211_iface_init(void)
1566 {
1567 	return register_netdevice_notifier(&mac80211_netdev_notifier);
1568 }
1569 
1570 void ieee80211_iface_exit(void)
1571 {
1572 	unregister_netdevice_notifier(&mac80211_netdev_notifier);
1573 }
1574