xref: /openbmc/linux/net/wireless/wext-core.c (revision 78700c0a)
1 /*
2  * This file implement the Wireless Extensions core API.
3  *
4  * Authors :	Jean Tourrilhes - HPL - <jt@hpl.hp.com>
5  * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
6  * Copyright	2009 Johannes Berg <johannes@sipsolutions.net>
7  *
8  * (As all part of the Linux kernel, this file is GPL)
9  */
10 #include <linux/kernel.h>
11 #include <linux/netdevice.h>
12 #include <linux/rtnetlink.h>
13 #include <linux/slab.h>
14 #include <linux/wireless.h>
15 #include <linux/uaccess.h>
16 #include <linux/export.h>
17 #include <net/cfg80211.h>
18 #include <net/iw_handler.h>
19 #include <net/netlink.h>
20 #include <net/wext.h>
21 #include <net/net_namespace.h>
22 
23 typedef int (*wext_ioctl_func)(struct net_device *, struct iwreq *,
24 			       unsigned int, struct iw_request_info *,
25 			       iw_handler);
26 
27 
28 /*
29  * Meta-data about all the standard Wireless Extension request we
30  * know about.
31  */
32 static const struct iw_ioctl_description standard_ioctl[] = {
33 	[IW_IOCTL_IDX(SIOCSIWCOMMIT)] = {
34 		.header_type	= IW_HEADER_TYPE_NULL,
35 	},
36 	[IW_IOCTL_IDX(SIOCGIWNAME)] = {
37 		.header_type	= IW_HEADER_TYPE_CHAR,
38 		.flags		= IW_DESCR_FLAG_DUMP,
39 	},
40 	[IW_IOCTL_IDX(SIOCSIWNWID)] = {
41 		.header_type	= IW_HEADER_TYPE_PARAM,
42 		.flags		= IW_DESCR_FLAG_EVENT,
43 	},
44 	[IW_IOCTL_IDX(SIOCGIWNWID)] = {
45 		.header_type	= IW_HEADER_TYPE_PARAM,
46 		.flags		= IW_DESCR_FLAG_DUMP,
47 	},
48 	[IW_IOCTL_IDX(SIOCSIWFREQ)] = {
49 		.header_type	= IW_HEADER_TYPE_FREQ,
50 		.flags		= IW_DESCR_FLAG_EVENT,
51 	},
52 	[IW_IOCTL_IDX(SIOCGIWFREQ)] = {
53 		.header_type	= IW_HEADER_TYPE_FREQ,
54 		.flags		= IW_DESCR_FLAG_DUMP,
55 	},
56 	[IW_IOCTL_IDX(SIOCSIWMODE)] = {
57 		.header_type	= IW_HEADER_TYPE_UINT,
58 		.flags		= IW_DESCR_FLAG_EVENT,
59 	},
60 	[IW_IOCTL_IDX(SIOCGIWMODE)] = {
61 		.header_type	= IW_HEADER_TYPE_UINT,
62 		.flags		= IW_DESCR_FLAG_DUMP,
63 	},
64 	[IW_IOCTL_IDX(SIOCSIWSENS)] = {
65 		.header_type	= IW_HEADER_TYPE_PARAM,
66 	},
67 	[IW_IOCTL_IDX(SIOCGIWSENS)] = {
68 		.header_type	= IW_HEADER_TYPE_PARAM,
69 	},
70 	[IW_IOCTL_IDX(SIOCSIWRANGE)] = {
71 		.header_type	= IW_HEADER_TYPE_NULL,
72 	},
73 	[IW_IOCTL_IDX(SIOCGIWRANGE)] = {
74 		.header_type	= IW_HEADER_TYPE_POINT,
75 		.token_size	= 1,
76 		.max_tokens	= sizeof(struct iw_range),
77 		.flags		= IW_DESCR_FLAG_DUMP,
78 	},
79 	[IW_IOCTL_IDX(SIOCSIWPRIV)] = {
80 		.header_type	= IW_HEADER_TYPE_NULL,
81 	},
82 	[IW_IOCTL_IDX(SIOCGIWPRIV)] = { /* (handled directly by us) */
83 		.header_type	= IW_HEADER_TYPE_POINT,
84 		.token_size	= sizeof(struct iw_priv_args),
85 		.max_tokens	= 16,
86 		.flags		= IW_DESCR_FLAG_NOMAX,
87 	},
88 	[IW_IOCTL_IDX(SIOCSIWSTATS)] = {
89 		.header_type	= IW_HEADER_TYPE_NULL,
90 	},
91 	[IW_IOCTL_IDX(SIOCGIWSTATS)] = { /* (handled directly by us) */
92 		.header_type	= IW_HEADER_TYPE_POINT,
93 		.token_size	= 1,
94 		.max_tokens	= sizeof(struct iw_statistics),
95 		.flags		= IW_DESCR_FLAG_DUMP,
96 	},
97 	[IW_IOCTL_IDX(SIOCSIWSPY)] = {
98 		.header_type	= IW_HEADER_TYPE_POINT,
99 		.token_size	= sizeof(struct sockaddr),
100 		.max_tokens	= IW_MAX_SPY,
101 	},
102 	[IW_IOCTL_IDX(SIOCGIWSPY)] = {
103 		.header_type	= IW_HEADER_TYPE_POINT,
104 		.token_size	= sizeof(struct sockaddr) +
105 				  sizeof(struct iw_quality),
106 		.max_tokens	= IW_MAX_SPY,
107 	},
108 	[IW_IOCTL_IDX(SIOCSIWTHRSPY)] = {
109 		.header_type	= IW_HEADER_TYPE_POINT,
110 		.token_size	= sizeof(struct iw_thrspy),
111 		.min_tokens	= 1,
112 		.max_tokens	= 1,
113 	},
114 	[IW_IOCTL_IDX(SIOCGIWTHRSPY)] = {
115 		.header_type	= IW_HEADER_TYPE_POINT,
116 		.token_size	= sizeof(struct iw_thrspy),
117 		.min_tokens	= 1,
118 		.max_tokens	= 1,
119 	},
120 	[IW_IOCTL_IDX(SIOCSIWAP)] = {
121 		.header_type	= IW_HEADER_TYPE_ADDR,
122 	},
123 	[IW_IOCTL_IDX(SIOCGIWAP)] = {
124 		.header_type	= IW_HEADER_TYPE_ADDR,
125 		.flags		= IW_DESCR_FLAG_DUMP,
126 	},
127 	[IW_IOCTL_IDX(SIOCSIWMLME)] = {
128 		.header_type	= IW_HEADER_TYPE_POINT,
129 		.token_size	= 1,
130 		.min_tokens	= sizeof(struct iw_mlme),
131 		.max_tokens	= sizeof(struct iw_mlme),
132 	},
133 	[IW_IOCTL_IDX(SIOCGIWAPLIST)] = {
134 		.header_type	= IW_HEADER_TYPE_POINT,
135 		.token_size	= sizeof(struct sockaddr) +
136 				  sizeof(struct iw_quality),
137 		.max_tokens	= IW_MAX_AP,
138 		.flags		= IW_DESCR_FLAG_NOMAX,
139 	},
140 	[IW_IOCTL_IDX(SIOCSIWSCAN)] = {
141 		.header_type	= IW_HEADER_TYPE_POINT,
142 		.token_size	= 1,
143 		.min_tokens	= 0,
144 		.max_tokens	= sizeof(struct iw_scan_req),
145 	},
146 	[IW_IOCTL_IDX(SIOCGIWSCAN)] = {
147 		.header_type	= IW_HEADER_TYPE_POINT,
148 		.token_size	= 1,
149 		.max_tokens	= IW_SCAN_MAX_DATA,
150 		.flags		= IW_DESCR_FLAG_NOMAX,
151 	},
152 	[IW_IOCTL_IDX(SIOCSIWESSID)] = {
153 		.header_type	= IW_HEADER_TYPE_POINT,
154 		.token_size	= 1,
155 		.max_tokens	= IW_ESSID_MAX_SIZE,
156 		.flags		= IW_DESCR_FLAG_EVENT,
157 	},
158 	[IW_IOCTL_IDX(SIOCGIWESSID)] = {
159 		.header_type	= IW_HEADER_TYPE_POINT,
160 		.token_size	= 1,
161 		.max_tokens	= IW_ESSID_MAX_SIZE,
162 		.flags		= IW_DESCR_FLAG_DUMP,
163 	},
164 	[IW_IOCTL_IDX(SIOCSIWNICKN)] = {
165 		.header_type	= IW_HEADER_TYPE_POINT,
166 		.token_size	= 1,
167 		.max_tokens	= IW_ESSID_MAX_SIZE,
168 	},
169 	[IW_IOCTL_IDX(SIOCGIWNICKN)] = {
170 		.header_type	= IW_HEADER_TYPE_POINT,
171 		.token_size	= 1,
172 		.max_tokens	= IW_ESSID_MAX_SIZE,
173 	},
174 	[IW_IOCTL_IDX(SIOCSIWRATE)] = {
175 		.header_type	= IW_HEADER_TYPE_PARAM,
176 	},
177 	[IW_IOCTL_IDX(SIOCGIWRATE)] = {
178 		.header_type	= IW_HEADER_TYPE_PARAM,
179 	},
180 	[IW_IOCTL_IDX(SIOCSIWRTS)] = {
181 		.header_type	= IW_HEADER_TYPE_PARAM,
182 	},
183 	[IW_IOCTL_IDX(SIOCGIWRTS)] = {
184 		.header_type	= IW_HEADER_TYPE_PARAM,
185 	},
186 	[IW_IOCTL_IDX(SIOCSIWFRAG)] = {
187 		.header_type	= IW_HEADER_TYPE_PARAM,
188 	},
189 	[IW_IOCTL_IDX(SIOCGIWFRAG)] = {
190 		.header_type	= IW_HEADER_TYPE_PARAM,
191 	},
192 	[IW_IOCTL_IDX(SIOCSIWTXPOW)] = {
193 		.header_type	= IW_HEADER_TYPE_PARAM,
194 	},
195 	[IW_IOCTL_IDX(SIOCGIWTXPOW)] = {
196 		.header_type	= IW_HEADER_TYPE_PARAM,
197 	},
198 	[IW_IOCTL_IDX(SIOCSIWRETRY)] = {
199 		.header_type	= IW_HEADER_TYPE_PARAM,
200 	},
201 	[IW_IOCTL_IDX(SIOCGIWRETRY)] = {
202 		.header_type	= IW_HEADER_TYPE_PARAM,
203 	},
204 	[IW_IOCTL_IDX(SIOCSIWENCODE)] = {
205 		.header_type	= IW_HEADER_TYPE_POINT,
206 		.token_size	= 1,
207 		.max_tokens	= IW_ENCODING_TOKEN_MAX,
208 		.flags		= IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT,
209 	},
210 	[IW_IOCTL_IDX(SIOCGIWENCODE)] = {
211 		.header_type	= IW_HEADER_TYPE_POINT,
212 		.token_size	= 1,
213 		.max_tokens	= IW_ENCODING_TOKEN_MAX,
214 		.flags		= IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT,
215 	},
216 	[IW_IOCTL_IDX(SIOCSIWPOWER)] = {
217 		.header_type	= IW_HEADER_TYPE_PARAM,
218 	},
219 	[IW_IOCTL_IDX(SIOCGIWPOWER)] = {
220 		.header_type	= IW_HEADER_TYPE_PARAM,
221 	},
222 	[IW_IOCTL_IDX(SIOCSIWGENIE)] = {
223 		.header_type	= IW_HEADER_TYPE_POINT,
224 		.token_size	= 1,
225 		.max_tokens	= IW_GENERIC_IE_MAX,
226 	},
227 	[IW_IOCTL_IDX(SIOCGIWGENIE)] = {
228 		.header_type	= IW_HEADER_TYPE_POINT,
229 		.token_size	= 1,
230 		.max_tokens	= IW_GENERIC_IE_MAX,
231 	},
232 	[IW_IOCTL_IDX(SIOCSIWAUTH)] = {
233 		.header_type	= IW_HEADER_TYPE_PARAM,
234 	},
235 	[IW_IOCTL_IDX(SIOCGIWAUTH)] = {
236 		.header_type	= IW_HEADER_TYPE_PARAM,
237 	},
238 	[IW_IOCTL_IDX(SIOCSIWENCODEEXT)] = {
239 		.header_type	= IW_HEADER_TYPE_POINT,
240 		.token_size	= 1,
241 		.min_tokens	= sizeof(struct iw_encode_ext),
242 		.max_tokens	= sizeof(struct iw_encode_ext) +
243 				  IW_ENCODING_TOKEN_MAX,
244 	},
245 	[IW_IOCTL_IDX(SIOCGIWENCODEEXT)] = {
246 		.header_type	= IW_HEADER_TYPE_POINT,
247 		.token_size	= 1,
248 		.min_tokens	= sizeof(struct iw_encode_ext),
249 		.max_tokens	= sizeof(struct iw_encode_ext) +
250 				  IW_ENCODING_TOKEN_MAX,
251 	},
252 	[IW_IOCTL_IDX(SIOCSIWPMKSA)] = {
253 		.header_type	= IW_HEADER_TYPE_POINT,
254 		.token_size	= 1,
255 		.min_tokens	= sizeof(struct iw_pmksa),
256 		.max_tokens	= sizeof(struct iw_pmksa),
257 	},
258 };
259 static const unsigned int standard_ioctl_num = ARRAY_SIZE(standard_ioctl);
260 
261 /*
262  * Meta-data about all the additional standard Wireless Extension events
263  * we know about.
264  */
265 static const struct iw_ioctl_description standard_event[] = {
266 	[IW_EVENT_IDX(IWEVTXDROP)] = {
267 		.header_type	= IW_HEADER_TYPE_ADDR,
268 	},
269 	[IW_EVENT_IDX(IWEVQUAL)] = {
270 		.header_type	= IW_HEADER_TYPE_QUAL,
271 	},
272 	[IW_EVENT_IDX(IWEVCUSTOM)] = {
273 		.header_type	= IW_HEADER_TYPE_POINT,
274 		.token_size	= 1,
275 		.max_tokens	= IW_CUSTOM_MAX,
276 	},
277 	[IW_EVENT_IDX(IWEVREGISTERED)] = {
278 		.header_type	= IW_HEADER_TYPE_ADDR,
279 	},
280 	[IW_EVENT_IDX(IWEVEXPIRED)] = {
281 		.header_type	= IW_HEADER_TYPE_ADDR,
282 	},
283 	[IW_EVENT_IDX(IWEVGENIE)] = {
284 		.header_type	= IW_HEADER_TYPE_POINT,
285 		.token_size	= 1,
286 		.max_tokens	= IW_GENERIC_IE_MAX,
287 	},
288 	[IW_EVENT_IDX(IWEVMICHAELMICFAILURE)] = {
289 		.header_type	= IW_HEADER_TYPE_POINT,
290 		.token_size	= 1,
291 		.max_tokens	= sizeof(struct iw_michaelmicfailure),
292 	},
293 	[IW_EVENT_IDX(IWEVASSOCREQIE)] = {
294 		.header_type	= IW_HEADER_TYPE_POINT,
295 		.token_size	= 1,
296 		.max_tokens	= IW_GENERIC_IE_MAX,
297 	},
298 	[IW_EVENT_IDX(IWEVASSOCRESPIE)] = {
299 		.header_type	= IW_HEADER_TYPE_POINT,
300 		.token_size	= 1,
301 		.max_tokens	= IW_GENERIC_IE_MAX,
302 	},
303 	[IW_EVENT_IDX(IWEVPMKIDCAND)] = {
304 		.header_type	= IW_HEADER_TYPE_POINT,
305 		.token_size	= 1,
306 		.max_tokens	= sizeof(struct iw_pmkid_cand),
307 	},
308 };
309 static const unsigned int standard_event_num = ARRAY_SIZE(standard_event);
310 
311 /* Size (in bytes) of various events */
312 static const int event_type_size[] = {
313 	IW_EV_LCP_LEN,			/* IW_HEADER_TYPE_NULL */
314 	0,
315 	IW_EV_CHAR_LEN,			/* IW_HEADER_TYPE_CHAR */
316 	0,
317 	IW_EV_UINT_LEN,			/* IW_HEADER_TYPE_UINT */
318 	IW_EV_FREQ_LEN,			/* IW_HEADER_TYPE_FREQ */
319 	IW_EV_ADDR_LEN,			/* IW_HEADER_TYPE_ADDR */
320 	0,
321 	IW_EV_POINT_LEN,		/* Without variable payload */
322 	IW_EV_PARAM_LEN,		/* IW_HEADER_TYPE_PARAM */
323 	IW_EV_QUAL_LEN,			/* IW_HEADER_TYPE_QUAL */
324 };
325 
326 #ifdef CONFIG_COMPAT
327 static const int compat_event_type_size[] = {
328 	IW_EV_COMPAT_LCP_LEN,		/* IW_HEADER_TYPE_NULL */
329 	0,
330 	IW_EV_COMPAT_CHAR_LEN,		/* IW_HEADER_TYPE_CHAR */
331 	0,
332 	IW_EV_COMPAT_UINT_LEN,		/* IW_HEADER_TYPE_UINT */
333 	IW_EV_COMPAT_FREQ_LEN,		/* IW_HEADER_TYPE_FREQ */
334 	IW_EV_COMPAT_ADDR_LEN,		/* IW_HEADER_TYPE_ADDR */
335 	0,
336 	IW_EV_COMPAT_POINT_LEN,		/* Without variable payload */
337 	IW_EV_COMPAT_PARAM_LEN,		/* IW_HEADER_TYPE_PARAM */
338 	IW_EV_COMPAT_QUAL_LEN,		/* IW_HEADER_TYPE_QUAL */
339 };
340 #endif
341 
342 
343 /* IW event code */
344 
345 void wireless_nlevent_flush(void)
346 {
347 	struct sk_buff *skb;
348 	struct net *net;
349 
350 	ASSERT_RTNL();
351 
352 	for_each_net(net) {
353 		while ((skb = skb_dequeue(&net->wext_nlevents)))
354 			rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL,
355 				    GFP_KERNEL);
356 	}
357 }
358 EXPORT_SYMBOL_GPL(wireless_nlevent_flush);
359 
360 static int wext_netdev_notifier_call(struct notifier_block *nb,
361 				     unsigned long state, void *ptr)
362 {
363 	/*
364 	 * When a netdev changes state in any way, flush all pending messages
365 	 * to avoid them going out in a strange order, e.g. RTM_NEWLINK after
366 	 * RTM_DELLINK, or with IFF_UP after without IFF_UP during dev_close()
367 	 * or similar - all of which could otherwise happen due to delays from
368 	 * schedule_work().
369 	 */
370 	wireless_nlevent_flush();
371 
372 	return NOTIFY_OK;
373 }
374 
375 static struct notifier_block wext_netdev_notifier = {
376 	.notifier_call = wext_netdev_notifier_call,
377 };
378 
379 static int __net_init wext_pernet_init(struct net *net)
380 {
381 	skb_queue_head_init(&net->wext_nlevents);
382 	return 0;
383 }
384 
385 static void __net_exit wext_pernet_exit(struct net *net)
386 {
387 	skb_queue_purge(&net->wext_nlevents);
388 }
389 
390 static struct pernet_operations wext_pernet_ops = {
391 	.init = wext_pernet_init,
392 	.exit = wext_pernet_exit,
393 };
394 
395 static int __init wireless_nlevent_init(void)
396 {
397 	int err = register_pernet_subsys(&wext_pernet_ops);
398 
399 	if (err)
400 		return err;
401 
402 	err = register_netdevice_notifier(&wext_netdev_notifier);
403 	if (err)
404 		unregister_pernet_subsys(&wext_pernet_ops);
405 	return err;
406 }
407 
408 subsys_initcall(wireless_nlevent_init);
409 
410 /* Process events generated by the wireless layer or the driver. */
411 static void wireless_nlevent_process(struct work_struct *work)
412 {
413 	rtnl_lock();
414 	wireless_nlevent_flush();
415 	rtnl_unlock();
416 }
417 
418 static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
419 
420 static struct nlmsghdr *rtnetlink_ifinfo_prep(struct net_device *dev,
421 					      struct sk_buff *skb)
422 {
423 	struct ifinfomsg *r;
424 	struct nlmsghdr  *nlh;
425 
426 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
427 	if (!nlh)
428 		return NULL;
429 
430 	r = nlmsg_data(nlh);
431 	r->ifi_family = AF_UNSPEC;
432 	r->__ifi_pad = 0;
433 	r->ifi_type = dev->type;
434 	r->ifi_index = dev->ifindex;
435 	r->ifi_flags = dev_get_flags(dev);
436 	r->ifi_change = 0;	/* Wireless changes don't affect those flags */
437 
438 	if (nla_put_string(skb, IFLA_IFNAME, dev->name))
439 		goto nla_put_failure;
440 
441 	return nlh;
442  nla_put_failure:
443 	nlmsg_cancel(skb, nlh);
444 	return NULL;
445 }
446 
447 
448 /*
449  * Main event dispatcher. Called from other parts and drivers.
450  * Send the event on the appropriate channels.
451  * May be called from interrupt context.
452  */
453 void wireless_send_event(struct net_device *	dev,
454 			 unsigned int		cmd,
455 			 union iwreq_data *	wrqu,
456 			 const char *		extra)
457 {
458 	const struct iw_ioctl_description *	descr = NULL;
459 	int extra_len = 0;
460 	struct iw_event  *event;		/* Mallocated whole event */
461 	int event_len;				/* Its size */
462 	int hdr_len;				/* Size of the event header */
463 	int wrqu_off = 0;			/* Offset in wrqu */
464 	/* Don't "optimise" the following variable, it will crash */
465 	unsigned int	cmd_index;		/* *MUST* be unsigned */
466 	struct sk_buff *skb;
467 	struct nlmsghdr *nlh;
468 	struct nlattr *nla;
469 #ifdef CONFIG_COMPAT
470 	struct __compat_iw_event *compat_event;
471 	struct compat_iw_point compat_wrqu;
472 	struct sk_buff *compskb;
473 #endif
474 
475 	/*
476 	 * Nothing in the kernel sends scan events with data, be safe.
477 	 * This is necessary because we cannot fix up scan event data
478 	 * for compat, due to being contained in 'extra', but normally
479 	 * applications are required to retrieve the scan data anyway
480 	 * and no data is included in the event, this codifies that
481 	 * practice.
482 	 */
483 	if (WARN_ON(cmd == SIOCGIWSCAN && extra))
484 		extra = NULL;
485 
486 	/* Get the description of the Event */
487 	if (cmd <= SIOCIWLAST) {
488 		cmd_index = IW_IOCTL_IDX(cmd);
489 		if (cmd_index < standard_ioctl_num)
490 			descr = &(standard_ioctl[cmd_index]);
491 	} else {
492 		cmd_index = IW_EVENT_IDX(cmd);
493 		if (cmd_index < standard_event_num)
494 			descr = &(standard_event[cmd_index]);
495 	}
496 	/* Don't accept unknown events */
497 	if (descr == NULL) {
498 		/* Note : we don't return an error to the driver, because
499 		 * the driver would not know what to do about it. It can't
500 		 * return an error to the user, because the event is not
501 		 * initiated by a user request.
502 		 * The best the driver could do is to log an error message.
503 		 * We will do it ourselves instead...
504 		 */
505 		netdev_err(dev, "(WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
506 			   cmd);
507 		return;
508 	}
509 
510 	/* Check extra parameters and set extra_len */
511 	if (descr->header_type == IW_HEADER_TYPE_POINT) {
512 		/* Check if number of token fits within bounds */
513 		if (wrqu->data.length > descr->max_tokens) {
514 			netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too big (%d)\n",
515 				   cmd, wrqu->data.length);
516 			return;
517 		}
518 		if (wrqu->data.length < descr->min_tokens) {
519 			netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too small (%d)\n",
520 				   cmd, wrqu->data.length);
521 			return;
522 		}
523 		/* Calculate extra_len - extra is NULL for restricted events */
524 		if (extra != NULL)
525 			extra_len = wrqu->data.length * descr->token_size;
526 		/* Always at an offset in wrqu */
527 		wrqu_off = IW_EV_POINT_OFF;
528 	}
529 
530 	/* Total length of the event */
531 	hdr_len = event_type_size[descr->header_type];
532 	event_len = hdr_len + extra_len;
533 
534 	/*
535 	 * The problem for 64/32 bit.
536 	 *
537 	 * On 64-bit, a regular event is laid out as follows:
538 	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
539 	 *      | event.len | event.cmd |     p a d d i n g     |
540 	 *      | wrqu data ... (with the correct size)         |
541 	 *
542 	 * This padding exists because we manipulate event->u,
543 	 * and 'event' is not packed.
544 	 *
545 	 * An iw_point event is laid out like this instead:
546 	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
547 	 *      | event.len | event.cmd |     p a d d i n g     |
548 	 *      | iwpnt.len | iwpnt.flg |     p a d d i n g     |
549 	 *      | extra data  ...
550 	 *
551 	 * The second padding exists because struct iw_point is extended,
552 	 * but this depends on the platform...
553 	 *
554 	 * On 32-bit, all the padding shouldn't be there.
555 	 */
556 
557 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
558 	if (!skb)
559 		return;
560 
561 	/* Send via the RtNetlink event channel */
562 	nlh = rtnetlink_ifinfo_prep(dev, skb);
563 	if (WARN_ON(!nlh)) {
564 		kfree_skb(skb);
565 		return;
566 	}
567 
568 	/* Add the wireless events in the netlink packet */
569 	nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
570 	if (!nla) {
571 		kfree_skb(skb);
572 		return;
573 	}
574 	event = nla_data(nla);
575 
576 	/* Fill event - first clear to avoid data leaking */
577 	memset(event, 0, hdr_len);
578 	event->len = event_len;
579 	event->cmd = cmd;
580 	memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
581 	if (extra_len)
582 		memcpy(((char *) event) + hdr_len, extra, extra_len);
583 
584 	nlmsg_end(skb, nlh);
585 #ifdef CONFIG_COMPAT
586 	hdr_len = compat_event_type_size[descr->header_type];
587 	event_len = hdr_len + extra_len;
588 
589 	compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
590 	if (!compskb) {
591 		kfree_skb(skb);
592 		return;
593 	}
594 
595 	/* Send via the RtNetlink event channel */
596 	nlh = rtnetlink_ifinfo_prep(dev, compskb);
597 	if (WARN_ON(!nlh)) {
598 		kfree_skb(skb);
599 		kfree_skb(compskb);
600 		return;
601 	}
602 
603 	/* Add the wireless events in the netlink packet */
604 	nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
605 	if (!nla) {
606 		kfree_skb(skb);
607 		kfree_skb(compskb);
608 		return;
609 	}
610 	compat_event = nla_data(nla);
611 
612 	compat_event->len = event_len;
613 	compat_event->cmd = cmd;
614 	if (descr->header_type == IW_HEADER_TYPE_POINT) {
615 		compat_wrqu.length = wrqu->data.length;
616 		compat_wrqu.flags = wrqu->data.flags;
617 		memcpy(&compat_event->pointer,
618 			((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
619 			hdr_len - IW_EV_COMPAT_LCP_LEN);
620 		if (extra_len)
621 			memcpy(((char *) compat_event) + hdr_len,
622 				extra, extra_len);
623 	} else {
624 		/* extra_len must be zero, so no if (extra) needed */
625 		memcpy(&compat_event->pointer, wrqu,
626 			hdr_len - IW_EV_COMPAT_LCP_LEN);
627 	}
628 
629 	nlmsg_end(compskb, nlh);
630 
631 	skb_shinfo(skb)->frag_list = compskb;
632 #endif
633 	skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
634 	schedule_work(&wireless_nlevent_work);
635 }
636 EXPORT_SYMBOL(wireless_send_event);
637 
638 
639 
640 /* IW handlers */
641 
642 struct iw_statistics *get_wireless_stats(struct net_device *dev)
643 {
644 #ifdef CONFIG_WIRELESS_EXT
645 	if ((dev->wireless_handlers != NULL) &&
646 	   (dev->wireless_handlers->get_wireless_stats != NULL))
647 		return dev->wireless_handlers->get_wireless_stats(dev);
648 #endif
649 
650 #ifdef CONFIG_CFG80211_WEXT
651 	if (dev->ieee80211_ptr &&
652 	    dev->ieee80211_ptr->wiphy &&
653 	    dev->ieee80211_ptr->wiphy->wext &&
654 	    dev->ieee80211_ptr->wiphy->wext->get_wireless_stats)
655 		return dev->ieee80211_ptr->wiphy->wext->get_wireless_stats(dev);
656 #endif
657 
658 	/* not found */
659 	return NULL;
660 }
661 
662 static int iw_handler_get_iwstats(struct net_device *		dev,
663 				  struct iw_request_info *	info,
664 				  union iwreq_data *		wrqu,
665 				  char *			extra)
666 {
667 	/* Get stats from the driver */
668 	struct iw_statistics *stats;
669 
670 	stats = get_wireless_stats(dev);
671 	if (stats) {
672 		/* Copy statistics to extra */
673 		memcpy(extra, stats, sizeof(struct iw_statistics));
674 		wrqu->data.length = sizeof(struct iw_statistics);
675 
676 		/* Check if we need to clear the updated flag */
677 		if (wrqu->data.flags != 0)
678 			stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
679 		return 0;
680 	} else
681 		return -EOPNOTSUPP;
682 }
683 
684 static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
685 {
686 	/* Don't "optimise" the following variable, it will crash */
687 	unsigned int	index;		/* *MUST* be unsigned */
688 	const struct iw_handler_def *handlers = NULL;
689 
690 #ifdef CONFIG_CFG80211_WEXT
691 	if (dev->ieee80211_ptr && dev->ieee80211_ptr->wiphy)
692 		handlers = dev->ieee80211_ptr->wiphy->wext;
693 #endif
694 #ifdef CONFIG_WIRELESS_EXT
695 	if (dev->wireless_handlers)
696 		handlers = dev->wireless_handlers;
697 #endif
698 
699 	if (!handlers)
700 		return NULL;
701 
702 	/* Try as a standard command */
703 	index = IW_IOCTL_IDX(cmd);
704 	if (index < handlers->num_standard)
705 		return handlers->standard[index];
706 
707 #ifdef CONFIG_WEXT_PRIV
708 	/* Try as a private command */
709 	index = cmd - SIOCIWFIRSTPRIV;
710 	if (index < handlers->num_private)
711 		return handlers->private[index];
712 #endif
713 
714 	/* Not found */
715 	return NULL;
716 }
717 
718 static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
719 				   const struct iw_ioctl_description *descr,
720 				   iw_handler handler, struct net_device *dev,
721 				   struct iw_request_info *info)
722 {
723 	int err, extra_size, user_length = 0, essid_compat = 0;
724 	char *extra;
725 
726 	/* Calculate space needed by arguments. Always allocate
727 	 * for max space.
728 	 */
729 	extra_size = descr->max_tokens * descr->token_size;
730 
731 	/* Check need for ESSID compatibility for WE < 21 */
732 	switch (cmd) {
733 	case SIOCSIWESSID:
734 	case SIOCGIWESSID:
735 	case SIOCSIWNICKN:
736 	case SIOCGIWNICKN:
737 		if (iwp->length == descr->max_tokens + 1)
738 			essid_compat = 1;
739 		else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
740 			char essid[IW_ESSID_MAX_SIZE + 1];
741 			unsigned int len;
742 			len = iwp->length * descr->token_size;
743 
744 			if (len > IW_ESSID_MAX_SIZE)
745 				return -EFAULT;
746 
747 			err = copy_from_user(essid, iwp->pointer, len);
748 			if (err)
749 				return -EFAULT;
750 
751 			if (essid[iwp->length - 1] == '\0')
752 				essid_compat = 1;
753 		}
754 		break;
755 	default:
756 		break;
757 	}
758 
759 	iwp->length -= essid_compat;
760 
761 	/* Check what user space is giving us */
762 	if (IW_IS_SET(cmd)) {
763 		/* Check NULL pointer */
764 		if (!iwp->pointer && iwp->length != 0)
765 			return -EFAULT;
766 		/* Check if number of token fits within bounds */
767 		if (iwp->length > descr->max_tokens)
768 			return -E2BIG;
769 		if (iwp->length < descr->min_tokens)
770 			return -EINVAL;
771 	} else {
772 		/* Check NULL pointer */
773 		if (!iwp->pointer)
774 			return -EFAULT;
775 		/* Save user space buffer size for checking */
776 		user_length = iwp->length;
777 
778 		/* Don't check if user_length > max to allow forward
779 		 * compatibility. The test user_length < min is
780 		 * implied by the test at the end.
781 		 */
782 
783 		/* Support for very large requests */
784 		if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
785 		    (user_length > descr->max_tokens)) {
786 			/* Allow userspace to GET more than max so
787 			 * we can support any size GET requests.
788 			 * There is still a limit : -ENOMEM.
789 			 */
790 			extra_size = user_length * descr->token_size;
791 
792 			/* Note : user_length is originally a __u16,
793 			 * and token_size is controlled by us,
794 			 * so extra_size won't get negative and
795 			 * won't overflow...
796 			 */
797 		}
798 	}
799 
800 	/* kzalloc() ensures NULL-termination for essid_compat. */
801 	extra = kzalloc(extra_size, GFP_KERNEL);
802 	if (!extra)
803 		return -ENOMEM;
804 
805 	/* If it is a SET, get all the extra data in here */
806 	if (IW_IS_SET(cmd) && (iwp->length != 0)) {
807 		if (copy_from_user(extra, iwp->pointer,
808 				   iwp->length *
809 				   descr->token_size)) {
810 			err = -EFAULT;
811 			goto out;
812 		}
813 
814 		if (cmd == SIOCSIWENCODEEXT) {
815 			struct iw_encode_ext *ee = (void *) extra;
816 
817 			if (iwp->length < sizeof(*ee) + ee->key_len) {
818 				err = -EFAULT;
819 				goto out;
820 			}
821 		}
822 	}
823 
824 	if (IW_IS_GET(cmd) && !(descr->flags & IW_DESCR_FLAG_NOMAX)) {
825 		/*
826 		 * If this is a GET, but not NOMAX, it means that the extra
827 		 * data is not bounded by userspace, but by max_tokens. Thus
828 		 * set the length to max_tokens. This matches the extra data
829 		 * allocation.
830 		 * The driver should fill it with the number of tokens it
831 		 * provided, and it may check iwp->length rather than having
832 		 * knowledge of max_tokens. If the driver doesn't change the
833 		 * iwp->length, this ioctl just copies back max_token tokens
834 		 * filled with zeroes. Hopefully the driver isn't claiming
835 		 * them to be valid data.
836 		 */
837 		iwp->length = descr->max_tokens;
838 	}
839 
840 	err = handler(dev, info, (union iwreq_data *) iwp, extra);
841 
842 	iwp->length += essid_compat;
843 
844 	/* If we have something to return to the user */
845 	if (!err && IW_IS_GET(cmd)) {
846 		/* Check if there is enough buffer up there */
847 		if (user_length < iwp->length) {
848 			err = -E2BIG;
849 			goto out;
850 		}
851 
852 		if (copy_to_user(iwp->pointer, extra,
853 				 iwp->length *
854 				 descr->token_size)) {
855 			err = -EFAULT;
856 			goto out;
857 		}
858 	}
859 
860 	/* Generate an event to notify listeners of the change */
861 	if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
862 	    ((err == 0) || (err == -EIWCOMMIT))) {
863 		union iwreq_data *data = (union iwreq_data *) iwp;
864 
865 		if (descr->flags & IW_DESCR_FLAG_RESTRICT)
866 			/* If the event is restricted, don't
867 			 * export the payload.
868 			 */
869 			wireless_send_event(dev, cmd, data, NULL);
870 		else
871 			wireless_send_event(dev, cmd, data, extra);
872 	}
873 
874 out:
875 	kfree(extra);
876 	return err;
877 }
878 
879 /*
880  * Call the commit handler in the driver
881  * (if exist and if conditions are right)
882  *
883  * Note : our current commit strategy is currently pretty dumb,
884  * but we will be able to improve on that...
885  * The goal is to try to agreagate as many changes as possible
886  * before doing the commit. Drivers that will define a commit handler
887  * are usually those that need a reset after changing parameters, so
888  * we want to minimise the number of reset.
889  * A cool idea is to use a timer : at each "set" command, we re-set the
890  * timer, when the timer eventually fires, we call the driver.
891  * Hopefully, more on that later.
892  *
893  * Also, I'm waiting to see how many people will complain about the
894  * netif_running(dev) test. I'm open on that one...
895  * Hopefully, the driver will remember to do a commit in "open()" ;-)
896  */
897 int call_commit_handler(struct net_device *dev)
898 {
899 #ifdef CONFIG_WIRELESS_EXT
900 	if ((netif_running(dev)) &&
901 	   (dev->wireless_handlers->standard[0] != NULL))
902 		/* Call the commit handler on the driver */
903 		return dev->wireless_handlers->standard[0](dev, NULL,
904 							   NULL, NULL);
905 	else
906 		return 0;		/* Command completed successfully */
907 #else
908 	/* cfg80211 has no commit */
909 	return 0;
910 #endif
911 }
912 
913 /*
914  * Main IOCTl dispatcher.
915  * Check the type of IOCTL and call the appropriate wrapper...
916  */
917 static int wireless_process_ioctl(struct net *net, struct ifreq *ifr,
918 				  unsigned int cmd,
919 				  struct iw_request_info *info,
920 				  wext_ioctl_func standard,
921 				  wext_ioctl_func private)
922 {
923 	struct iwreq *iwr = (struct iwreq *) ifr;
924 	struct net_device *dev;
925 	iw_handler	handler;
926 
927 	/* Permissions are already checked in dev_ioctl() before calling us.
928 	 * The copy_to/from_user() of ifr is also dealt with in there */
929 
930 	/* Make sure the device exist */
931 	if ((dev = __dev_get_by_name(net, ifr->ifr_name)) == NULL)
932 		return -ENODEV;
933 
934 	/* A bunch of special cases, then the generic case...
935 	 * Note that 'cmd' is already filtered in dev_ioctl() with
936 	 * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
937 	if (cmd == SIOCGIWSTATS)
938 		return standard(dev, iwr, cmd, info,
939 				&iw_handler_get_iwstats);
940 
941 #ifdef CONFIG_WEXT_PRIV
942 	if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
943 		return standard(dev, iwr, cmd, info,
944 				iw_handler_get_private);
945 #endif
946 
947 	/* Basic check */
948 	if (!netif_device_present(dev))
949 		return -ENODEV;
950 
951 	/* New driver API : try to find the handler */
952 	handler = get_handler(dev, cmd);
953 	if (handler) {
954 		/* Standard and private are not the same */
955 		if (cmd < SIOCIWFIRSTPRIV)
956 			return standard(dev, iwr, cmd, info, handler);
957 		else if (private)
958 			return private(dev, iwr, cmd, info, handler);
959 	}
960 	/* Old driver API : call driver ioctl handler */
961 	if (dev->netdev_ops->ndo_do_ioctl)
962 		return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
963 	return -EOPNOTSUPP;
964 }
965 
966 /* If command is `set a parameter', or `get the encoding parameters',
967  * check if the user has the right to do it.
968  */
969 static int wext_permission_check(unsigned int cmd)
970 {
971 	if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE ||
972 	     cmd == SIOCGIWENCODEEXT) &&
973 	    !capable(CAP_NET_ADMIN))
974 		return -EPERM;
975 
976 	return 0;
977 }
978 
979 /* entry point from dev ioctl */
980 static int wext_ioctl_dispatch(struct net *net, struct ifreq *ifr,
981 			       unsigned int cmd, struct iw_request_info *info,
982 			       wext_ioctl_func standard,
983 			       wext_ioctl_func private)
984 {
985 	int ret = wext_permission_check(cmd);
986 
987 	if (ret)
988 		return ret;
989 
990 	dev_load(net, ifr->ifr_name);
991 	rtnl_lock();
992 	ret = wireless_process_ioctl(net, ifr, cmd, info, standard, private);
993 	rtnl_unlock();
994 
995 	return ret;
996 }
997 
998 /*
999  * Wrapper to call a standard Wireless Extension handler.
1000  * We do various checks and also take care of moving data between
1001  * user space and kernel space.
1002  */
1003 static int ioctl_standard_call(struct net_device *	dev,
1004 			       struct iwreq		*iwr,
1005 			       unsigned int		cmd,
1006 			       struct iw_request_info	*info,
1007 			       iw_handler		handler)
1008 {
1009 	const struct iw_ioctl_description *	descr;
1010 	int					ret = -EINVAL;
1011 
1012 	/* Get the description of the IOCTL */
1013 	if (IW_IOCTL_IDX(cmd) >= standard_ioctl_num)
1014 		return -EOPNOTSUPP;
1015 	descr = &(standard_ioctl[IW_IOCTL_IDX(cmd)]);
1016 
1017 	/* Check if we have a pointer to user space data or not */
1018 	if (descr->header_type != IW_HEADER_TYPE_POINT) {
1019 
1020 		/* No extra arguments. Trivial to handle */
1021 		ret = handler(dev, info, &(iwr->u), NULL);
1022 
1023 		/* Generate an event to notify listeners of the change */
1024 		if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
1025 		   ((ret == 0) || (ret == -EIWCOMMIT)))
1026 			wireless_send_event(dev, cmd, &(iwr->u), NULL);
1027 	} else {
1028 		ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
1029 					      handler, dev, info);
1030 	}
1031 
1032 	/* Call commit handler if needed and defined */
1033 	if (ret == -EIWCOMMIT)
1034 		ret = call_commit_handler(dev);
1035 
1036 	/* Here, we will generate the appropriate event if needed */
1037 
1038 	return ret;
1039 }
1040 
1041 
1042 int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
1043 		      void __user *arg)
1044 {
1045 	struct iw_request_info info = { .cmd = cmd, .flags = 0 };
1046 	int ret;
1047 
1048 	ret = wext_ioctl_dispatch(net, ifr, cmd, &info,
1049 				  ioctl_standard_call,
1050 				  ioctl_private_call);
1051 	if (ret >= 0 &&
1052 	    IW_IS_GET(cmd) &&
1053 	    copy_to_user(arg, ifr, sizeof(struct iwreq)))
1054 		return -EFAULT;
1055 
1056 	return ret;
1057 }
1058 
1059 #ifdef CONFIG_COMPAT
1060 static int compat_standard_call(struct net_device	*dev,
1061 				struct iwreq		*iwr,
1062 				unsigned int		cmd,
1063 				struct iw_request_info	*info,
1064 				iw_handler		handler)
1065 {
1066 	const struct iw_ioctl_description *descr;
1067 	struct compat_iw_point *iwp_compat;
1068 	struct iw_point iwp;
1069 	int err;
1070 
1071 	descr = standard_ioctl + IW_IOCTL_IDX(cmd);
1072 
1073 	if (descr->header_type != IW_HEADER_TYPE_POINT)
1074 		return ioctl_standard_call(dev, iwr, cmd, info, handler);
1075 
1076 	iwp_compat = (struct compat_iw_point *) &iwr->u.data;
1077 	iwp.pointer = compat_ptr(iwp_compat->pointer);
1078 	iwp.length = iwp_compat->length;
1079 	iwp.flags = iwp_compat->flags;
1080 
1081 	err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
1082 
1083 	iwp_compat->pointer = ptr_to_compat(iwp.pointer);
1084 	iwp_compat->length = iwp.length;
1085 	iwp_compat->flags = iwp.flags;
1086 
1087 	return err;
1088 }
1089 
1090 int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
1091 			     unsigned long arg)
1092 {
1093 	void __user *argp = (void __user *)arg;
1094 	struct iw_request_info info;
1095 	struct iwreq iwr;
1096 	char *colon;
1097 	int ret;
1098 
1099 	if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
1100 		return -EFAULT;
1101 
1102 	iwr.ifr_name[IFNAMSIZ-1] = 0;
1103 	colon = strchr(iwr.ifr_name, ':');
1104 	if (colon)
1105 		*colon = 0;
1106 
1107 	info.cmd = cmd;
1108 	info.flags = IW_REQUEST_FLAG_COMPAT;
1109 
1110 	ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd, &info,
1111 				  compat_standard_call,
1112 				  compat_private_call);
1113 
1114 	if (ret >= 0 &&
1115 	    IW_IS_GET(cmd) &&
1116 	    copy_to_user(argp, &iwr, sizeof(struct iwreq)))
1117 		return -EFAULT;
1118 
1119 	return ret;
1120 }
1121 #endif
1122