xref: /linux/net/wireless/wext-core.c (revision c6fbb759)
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 	down_read(&net_rwsem);
351 	for_each_net(net) {
352 		while ((skb = skb_dequeue(&net->wext_nlevents)))
353 			rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL,
354 				    GFP_KERNEL);
355 	}
356 	up_read(&net_rwsem);
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 	wireless_nlevent_flush();
414 }
415 
416 static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
417 
418 static struct nlmsghdr *rtnetlink_ifinfo_prep(struct net_device *dev,
419 					      struct sk_buff *skb)
420 {
421 	struct ifinfomsg *r;
422 	struct nlmsghdr  *nlh;
423 
424 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
425 	if (!nlh)
426 		return NULL;
427 
428 	r = nlmsg_data(nlh);
429 	r->ifi_family = AF_UNSPEC;
430 	r->__ifi_pad = 0;
431 	r->ifi_type = dev->type;
432 	r->ifi_index = dev->ifindex;
433 	r->ifi_flags = dev_get_flags(dev);
434 	r->ifi_change = 0;	/* Wireless changes don't affect those flags */
435 
436 	if (nla_put_string(skb, IFLA_IFNAME, dev->name))
437 		goto nla_put_failure;
438 
439 	return nlh;
440  nla_put_failure:
441 	nlmsg_cancel(skb, nlh);
442 	return NULL;
443 }
444 
445 
446 /*
447  * Main event dispatcher. Called from other parts and drivers.
448  * Send the event on the appropriate channels.
449  * May be called from interrupt context.
450  */
451 void wireless_send_event(struct net_device *	dev,
452 			 unsigned int		cmd,
453 			 union iwreq_data *	wrqu,
454 			 const char *		extra)
455 {
456 	const struct iw_ioctl_description *	descr = NULL;
457 	int extra_len = 0;
458 	struct iw_event  *event;		/* Mallocated whole event */
459 	int event_len;				/* Its size */
460 	int hdr_len;				/* Size of the event header */
461 	int wrqu_off = 0;			/* Offset in wrqu */
462 	/* Don't "optimise" the following variable, it will crash */
463 	unsigned int	cmd_index;		/* *MUST* be unsigned */
464 	struct sk_buff *skb;
465 	struct nlmsghdr *nlh;
466 	struct nlattr *nla;
467 #ifdef CONFIG_COMPAT
468 	struct __compat_iw_event *compat_event;
469 	struct compat_iw_point compat_wrqu;
470 	struct sk_buff *compskb;
471 	int ptr_len;
472 #endif
473 
474 	/*
475 	 * Nothing in the kernel sends scan events with data, be safe.
476 	 * This is necessary because we cannot fix up scan event data
477 	 * for compat, due to being contained in 'extra', but normally
478 	 * applications are required to retrieve the scan data anyway
479 	 * and no data is included in the event, this codifies that
480 	 * practice.
481 	 */
482 	if (WARN_ON(cmd == SIOCGIWSCAN && extra))
483 		extra = NULL;
484 
485 	/* Get the description of the Event */
486 	if (cmd <= SIOCIWLAST) {
487 		cmd_index = IW_IOCTL_IDX(cmd);
488 		if (cmd_index < standard_ioctl_num)
489 			descr = &(standard_ioctl[cmd_index]);
490 	} else {
491 		cmd_index = IW_EVENT_IDX(cmd);
492 		if (cmd_index < standard_event_num)
493 			descr = &(standard_event[cmd_index]);
494 	}
495 	/* Don't accept unknown events */
496 	if (descr == NULL) {
497 		/* Note : we don't return an error to the driver, because
498 		 * the driver would not know what to do about it. It can't
499 		 * return an error to the user, because the event is not
500 		 * initiated by a user request.
501 		 * The best the driver could do is to log an error message.
502 		 * We will do it ourselves instead...
503 		 */
504 		netdev_err(dev, "(WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
505 			   cmd);
506 		return;
507 	}
508 
509 	/* Check extra parameters and set extra_len */
510 	if (descr->header_type == IW_HEADER_TYPE_POINT) {
511 		/* Check if number of token fits within bounds */
512 		if (wrqu->data.length > descr->max_tokens) {
513 			netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too big (%d)\n",
514 				   cmd, wrqu->data.length);
515 			return;
516 		}
517 		if (wrqu->data.length < descr->min_tokens) {
518 			netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too small (%d)\n",
519 				   cmd, wrqu->data.length);
520 			return;
521 		}
522 		/* Calculate extra_len - extra is NULL for restricted events */
523 		if (extra != NULL)
524 			extra_len = wrqu->data.length * descr->token_size;
525 		/* Always at an offset in wrqu */
526 		wrqu_off = IW_EV_POINT_OFF;
527 	}
528 
529 	/* Total length of the event */
530 	hdr_len = event_type_size[descr->header_type];
531 	event_len = hdr_len + extra_len;
532 
533 	/*
534 	 * The problem for 64/32 bit.
535 	 *
536 	 * On 64-bit, a regular event is laid out as follows:
537 	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
538 	 *      | event.len | event.cmd |     p a d d i n g     |
539 	 *      | wrqu data ... (with the correct size)         |
540 	 *
541 	 * This padding exists because we manipulate event->u,
542 	 * and 'event' is not packed.
543 	 *
544 	 * An iw_point event is laid out like this instead:
545 	 *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
546 	 *      | event.len | event.cmd |     p a d d i n g     |
547 	 *      | iwpnt.len | iwpnt.flg |     p a d d i n g     |
548 	 *      | extra data  ...
549 	 *
550 	 * The second padding exists because struct iw_point is extended,
551 	 * but this depends on the platform...
552 	 *
553 	 * On 32-bit, all the padding shouldn't be there.
554 	 */
555 
556 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
557 	if (!skb)
558 		return;
559 
560 	/* Send via the RtNetlink event channel */
561 	nlh = rtnetlink_ifinfo_prep(dev, skb);
562 	if (WARN_ON(!nlh)) {
563 		kfree_skb(skb);
564 		return;
565 	}
566 
567 	/* Add the wireless events in the netlink packet */
568 	nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
569 	if (!nla) {
570 		kfree_skb(skb);
571 		return;
572 	}
573 	event = nla_data(nla);
574 
575 	/* Fill event - first clear to avoid data leaking */
576 	memset(event, 0, hdr_len);
577 	event->len = event_len;
578 	event->cmd = cmd;
579 	memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
580 	if (extra_len)
581 		memcpy(((char *) event) + hdr_len, extra, extra_len);
582 
583 	nlmsg_end(skb, nlh);
584 #ifdef CONFIG_COMPAT
585 	hdr_len = compat_event_type_size[descr->header_type];
586 
587 	/* ptr_len is remaining size in event header apart from LCP */
588 	ptr_len = hdr_len - IW_EV_COMPAT_LCP_LEN;
589 	event_len = hdr_len + extra_len;
590 
591 	compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
592 	if (!compskb) {
593 		kfree_skb(skb);
594 		return;
595 	}
596 
597 	/* Send via the RtNetlink event channel */
598 	nlh = rtnetlink_ifinfo_prep(dev, compskb);
599 	if (WARN_ON(!nlh)) {
600 		kfree_skb(skb);
601 		kfree_skb(compskb);
602 		return;
603 	}
604 
605 	/* Add the wireless events in the netlink packet */
606 	nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
607 	if (!nla) {
608 		kfree_skb(skb);
609 		kfree_skb(compskb);
610 		return;
611 	}
612 	compat_event = nla_data(nla);
613 
614 	compat_event->len = event_len;
615 	compat_event->cmd = cmd;
616 	if (descr->header_type == IW_HEADER_TYPE_POINT) {
617 		compat_wrqu.length = wrqu->data.length;
618 		compat_wrqu.flags = wrqu->data.flags;
619 		memcpy(compat_event->ptr_bytes,
620 		       ((char *)&compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
621 			ptr_len);
622 		if (extra_len)
623 			memcpy(&compat_event->ptr_bytes[ptr_len],
624 			       extra, extra_len);
625 	} else {
626 		/* extra_len must be zero, so no if (extra) needed */
627 		memcpy(compat_event->ptr_bytes, wrqu, ptr_len);
628 	}
629 
630 	nlmsg_end(compskb, nlh);
631 
632 	skb_shinfo(skb)->frag_list = compskb;
633 #endif
634 	skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
635 	schedule_work(&wireless_nlevent_work);
636 }
637 EXPORT_SYMBOL(wireless_send_event);
638 
639 
640 
641 /* IW handlers */
642 
643 struct iw_statistics *get_wireless_stats(struct net_device *dev)
644 {
645 #ifdef CONFIG_WIRELESS_EXT
646 	if ((dev->wireless_handlers != NULL) &&
647 	   (dev->wireless_handlers->get_wireless_stats != NULL))
648 		return dev->wireless_handlers->get_wireless_stats(dev);
649 #endif
650 
651 #ifdef CONFIG_CFG80211_WEXT
652 	if (dev->ieee80211_ptr &&
653 	    dev->ieee80211_ptr->wiphy &&
654 	    dev->ieee80211_ptr->wiphy->wext &&
655 	    dev->ieee80211_ptr->wiphy->wext->get_wireless_stats)
656 		return dev->ieee80211_ptr->wiphy->wext->get_wireless_stats(dev);
657 #endif
658 
659 	/* not found */
660 	return NULL;
661 }
662 
663 /* noinline to avoid a bogus warning with -O3 */
664 static noinline int iw_handler_get_iwstats(struct net_device *	dev,
665 				  struct iw_request_info *	info,
666 				  union iwreq_data *		wrqu,
667 				  char *			extra)
668 {
669 	/* Get stats from the driver */
670 	struct iw_statistics *stats;
671 
672 	stats = get_wireless_stats(dev);
673 	if (stats) {
674 		/* Copy statistics to extra */
675 		memcpy(extra, stats, sizeof(struct iw_statistics));
676 		wrqu->data.length = sizeof(struct iw_statistics);
677 
678 		/* Check if we need to clear the updated flag */
679 		if (wrqu->data.flags != 0)
680 			stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
681 		return 0;
682 	} else
683 		return -EOPNOTSUPP;
684 }
685 
686 static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
687 {
688 	/* Don't "optimise" the following variable, it will crash */
689 	unsigned int	index;		/* *MUST* be unsigned */
690 	const struct iw_handler_def *handlers = NULL;
691 
692 #ifdef CONFIG_CFG80211_WEXT
693 	if (dev->ieee80211_ptr && dev->ieee80211_ptr->wiphy)
694 		handlers = dev->ieee80211_ptr->wiphy->wext;
695 #endif
696 #ifdef CONFIG_WIRELESS_EXT
697 	if (dev->wireless_handlers)
698 		handlers = dev->wireless_handlers;
699 #endif
700 
701 	if (!handlers)
702 		return NULL;
703 
704 	/* Try as a standard command */
705 	index = IW_IOCTL_IDX(cmd);
706 	if (index < handlers->num_standard)
707 		return handlers->standard[index];
708 
709 #ifdef CONFIG_WEXT_PRIV
710 	/* Try as a private command */
711 	index = cmd - SIOCIWFIRSTPRIV;
712 	if (index < handlers->num_private)
713 		return handlers->private[index];
714 #endif
715 
716 	/* Not found */
717 	return NULL;
718 }
719 
720 static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
721 				   const struct iw_ioctl_description *descr,
722 				   iw_handler handler, struct net_device *dev,
723 				   struct iw_request_info *info)
724 {
725 	int err, extra_size, user_length = 0, essid_compat = 0;
726 	char *extra;
727 
728 	/* Calculate space needed by arguments. Always allocate
729 	 * for max space.
730 	 */
731 	extra_size = descr->max_tokens * descr->token_size;
732 
733 	/* Check need for ESSID compatibility for WE < 21 */
734 	switch (cmd) {
735 	case SIOCSIWESSID:
736 	case SIOCGIWESSID:
737 	case SIOCSIWNICKN:
738 	case SIOCGIWNICKN:
739 		if (iwp->length == descr->max_tokens + 1)
740 			essid_compat = 1;
741 		else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
742 			char essid[IW_ESSID_MAX_SIZE + 1];
743 			unsigned int len;
744 			len = iwp->length * descr->token_size;
745 
746 			if (len > IW_ESSID_MAX_SIZE)
747 				return -EFAULT;
748 
749 			err = copy_from_user(essid, iwp->pointer, len);
750 			if (err)
751 				return -EFAULT;
752 
753 			if (essid[iwp->length - 1] == '\0')
754 				essid_compat = 1;
755 		}
756 		break;
757 	default:
758 		break;
759 	}
760 
761 	iwp->length -= essid_compat;
762 
763 	/* Check what user space is giving us */
764 	if (IW_IS_SET(cmd)) {
765 		/* Check NULL pointer */
766 		if (!iwp->pointer && iwp->length != 0)
767 			return -EFAULT;
768 		/* Check if number of token fits within bounds */
769 		if (iwp->length > descr->max_tokens)
770 			return -E2BIG;
771 		if (iwp->length < descr->min_tokens)
772 			return -EINVAL;
773 	} else {
774 		/* Check NULL pointer */
775 		if (!iwp->pointer)
776 			return -EFAULT;
777 		/* Save user space buffer size for checking */
778 		user_length = iwp->length;
779 
780 		/* Don't check if user_length > max to allow forward
781 		 * compatibility. The test user_length < min is
782 		 * implied by the test at the end.
783 		 */
784 
785 		/* Support for very large requests */
786 		if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
787 		    (user_length > descr->max_tokens)) {
788 			/* Allow userspace to GET more than max so
789 			 * we can support any size GET requests.
790 			 * There is still a limit : -ENOMEM.
791 			 */
792 			extra_size = user_length * descr->token_size;
793 
794 			/* Note : user_length is originally a __u16,
795 			 * and token_size is controlled by us,
796 			 * so extra_size won't get negative and
797 			 * won't overflow...
798 			 */
799 		}
800 	}
801 
802 	/* kzalloc() ensures NULL-termination for essid_compat. */
803 	extra = kzalloc(extra_size, GFP_KERNEL);
804 	if (!extra)
805 		return -ENOMEM;
806 
807 	/* If it is a SET, get all the extra data in here */
808 	if (IW_IS_SET(cmd) && (iwp->length != 0)) {
809 		if (copy_from_user(extra, iwp->pointer,
810 				   iwp->length *
811 				   descr->token_size)) {
812 			err = -EFAULT;
813 			goto out;
814 		}
815 
816 		if (cmd == SIOCSIWENCODEEXT) {
817 			struct iw_encode_ext *ee = (void *) extra;
818 
819 			if (iwp->length < sizeof(*ee) + ee->key_len) {
820 				err = -EFAULT;
821 				goto out;
822 			}
823 		}
824 	}
825 
826 	if (IW_IS_GET(cmd) && !(descr->flags & IW_DESCR_FLAG_NOMAX)) {
827 		/*
828 		 * If this is a GET, but not NOMAX, it means that the extra
829 		 * data is not bounded by userspace, but by max_tokens. Thus
830 		 * set the length to max_tokens. This matches the extra data
831 		 * allocation.
832 		 * The driver should fill it with the number of tokens it
833 		 * provided, and it may check iwp->length rather than having
834 		 * knowledge of max_tokens. If the driver doesn't change the
835 		 * iwp->length, this ioctl just copies back max_token tokens
836 		 * filled with zeroes. Hopefully the driver isn't claiming
837 		 * them to be valid data.
838 		 */
839 		iwp->length = descr->max_tokens;
840 	}
841 
842 	err = handler(dev, info, (union iwreq_data *) iwp, extra);
843 
844 	iwp->length += essid_compat;
845 
846 	/* If we have something to return to the user */
847 	if (!err && IW_IS_GET(cmd)) {
848 		/* Check if there is enough buffer up there */
849 		if (user_length < iwp->length) {
850 			err = -E2BIG;
851 			goto out;
852 		}
853 
854 		if (copy_to_user(iwp->pointer, extra,
855 				 iwp->length *
856 				 descr->token_size)) {
857 			err = -EFAULT;
858 			goto out;
859 		}
860 	}
861 
862 	/* Generate an event to notify listeners of the change */
863 	if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
864 	    ((err == 0) || (err == -EIWCOMMIT))) {
865 		union iwreq_data *data = (union iwreq_data *) iwp;
866 
867 		if (descr->flags & IW_DESCR_FLAG_RESTRICT)
868 			/* If the event is restricted, don't
869 			 * export the payload.
870 			 */
871 			wireless_send_event(dev, cmd, data, NULL);
872 		else
873 			wireless_send_event(dev, cmd, data, extra);
874 	}
875 
876 out:
877 	kfree(extra);
878 	return err;
879 }
880 
881 /*
882  * Call the commit handler in the driver
883  * (if exist and if conditions are right)
884  *
885  * Note : our current commit strategy is currently pretty dumb,
886  * but we will be able to improve on that...
887  * The goal is to try to agreagate as many changes as possible
888  * before doing the commit. Drivers that will define a commit handler
889  * are usually those that need a reset after changing parameters, so
890  * we want to minimise the number of reset.
891  * A cool idea is to use a timer : at each "set" command, we re-set the
892  * timer, when the timer eventually fires, we call the driver.
893  * Hopefully, more on that later.
894  *
895  * Also, I'm waiting to see how many people will complain about the
896  * netif_running(dev) test. I'm open on that one...
897  * Hopefully, the driver will remember to do a commit in "open()" ;-)
898  */
899 int call_commit_handler(struct net_device *dev)
900 {
901 #ifdef CONFIG_WIRELESS_EXT
902 	if (netif_running(dev) &&
903 	    dev->wireless_handlers &&
904 	    dev->wireless_handlers->standard[0])
905 		/* Call the commit handler on the driver */
906 		return dev->wireless_handlers->standard[0](dev, NULL,
907 							   NULL, NULL);
908 	else
909 		return 0;		/* Command completed successfully */
910 #else
911 	/* cfg80211 has no commit */
912 	return 0;
913 #endif
914 }
915 
916 /*
917  * Main IOCTl dispatcher.
918  * Check the type of IOCTL and call the appropriate wrapper...
919  */
920 static int wireless_process_ioctl(struct net *net, struct iwreq *iwr,
921 				  unsigned int cmd,
922 				  struct iw_request_info *info,
923 				  wext_ioctl_func standard,
924 				  wext_ioctl_func private)
925 {
926 	struct net_device *dev;
927 	iw_handler	handler;
928 
929 	/* Permissions are already checked in dev_ioctl() before calling us.
930 	 * The copy_to/from_user() of ifr is also dealt with in there */
931 
932 	/* Make sure the device exist */
933 	if ((dev = __dev_get_by_name(net, iwr->ifr_name)) == NULL)
934 		return -ENODEV;
935 
936 	/* A bunch of special cases, then the generic case...
937 	 * Note that 'cmd' is already filtered in dev_ioctl() with
938 	 * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
939 	if (cmd == SIOCGIWSTATS)
940 		return standard(dev, iwr, cmd, info,
941 				&iw_handler_get_iwstats);
942 
943 #ifdef CONFIG_WEXT_PRIV
944 	if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
945 		return standard(dev, iwr, cmd, info,
946 				iw_handler_get_private);
947 #endif
948 
949 	/* Basic check */
950 	if (!netif_device_present(dev))
951 		return -ENODEV;
952 
953 	/* New driver API : try to find the handler */
954 	handler = get_handler(dev, cmd);
955 	if (handler) {
956 		/* Standard and private are not the same */
957 		if (cmd < SIOCIWFIRSTPRIV)
958 			return standard(dev, iwr, cmd, info, handler);
959 		else if (private)
960 			return private(dev, iwr, cmd, info, handler);
961 	}
962 	return -EOPNOTSUPP;
963 }
964 
965 /* If command is `set a parameter', or `get the encoding parameters',
966  * check if the user has the right to do it.
967  */
968 static int wext_permission_check(unsigned int cmd)
969 {
970 	if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE ||
971 	     cmd == SIOCGIWENCODEEXT) &&
972 	    !capable(CAP_NET_ADMIN))
973 		return -EPERM;
974 
975 	return 0;
976 }
977 
978 /* entry point from dev ioctl */
979 static int wext_ioctl_dispatch(struct net *net, struct iwreq *iwr,
980 			       unsigned int cmd, struct iw_request_info *info,
981 			       wext_ioctl_func standard,
982 			       wext_ioctl_func private)
983 {
984 	int ret = wext_permission_check(cmd);
985 
986 	if (ret)
987 		return ret;
988 
989 	dev_load(net, iwr->ifr_name);
990 	rtnl_lock();
991 	ret = wireless_process_ioctl(net, iwr, cmd, info, standard, private);
992 	rtnl_unlock();
993 
994 	return ret;
995 }
996 
997 /*
998  * Wrapper to call a standard Wireless Extension handler.
999  * We do various checks and also take care of moving data between
1000  * user space and kernel space.
1001  */
1002 static int ioctl_standard_call(struct net_device *	dev,
1003 			       struct iwreq		*iwr,
1004 			       unsigned int		cmd,
1005 			       struct iw_request_info	*info,
1006 			       iw_handler		handler)
1007 {
1008 	const struct iw_ioctl_description *	descr;
1009 	int					ret = -EINVAL;
1010 
1011 	/* Get the description of the IOCTL */
1012 	if (IW_IOCTL_IDX(cmd) >= standard_ioctl_num)
1013 		return -EOPNOTSUPP;
1014 	descr = &(standard_ioctl[IW_IOCTL_IDX(cmd)]);
1015 
1016 	/* Check if we have a pointer to user space data or not */
1017 	if (descr->header_type != IW_HEADER_TYPE_POINT) {
1018 
1019 		/* No extra arguments. Trivial to handle */
1020 		ret = handler(dev, info, &(iwr->u), NULL);
1021 
1022 		/* Generate an event to notify listeners of the change */
1023 		if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
1024 		   ((ret == 0) || (ret == -EIWCOMMIT)))
1025 			wireless_send_event(dev, cmd, &(iwr->u), NULL);
1026 	} else {
1027 		ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
1028 					      handler, dev, info);
1029 	}
1030 
1031 	/* Call commit handler if needed and defined */
1032 	if (ret == -EIWCOMMIT)
1033 		ret = call_commit_handler(dev);
1034 
1035 	/* Here, we will generate the appropriate event if needed */
1036 
1037 	return ret;
1038 }
1039 
1040 
1041 int wext_handle_ioctl(struct net *net, unsigned int cmd, void __user *arg)
1042 {
1043 	struct iw_request_info info = { .cmd = cmd, .flags = 0 };
1044 	struct iwreq iwr;
1045 	int ret;
1046 
1047 	if (copy_from_user(&iwr, arg, sizeof(iwr)))
1048 		return -EFAULT;
1049 
1050 	iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
1051 
1052 	ret = wext_ioctl_dispatch(net, &iwr, cmd, &info,
1053 				  ioctl_standard_call,
1054 				  ioctl_private_call);
1055 	if (ret >= 0 &&
1056 	    IW_IS_GET(cmd) &&
1057 	    copy_to_user(arg, &iwr, sizeof(struct iwreq)))
1058 		return -EFAULT;
1059 
1060 	return ret;
1061 }
1062 
1063 #ifdef CONFIG_COMPAT
1064 static int compat_standard_call(struct net_device	*dev,
1065 				struct iwreq		*iwr,
1066 				unsigned int		cmd,
1067 				struct iw_request_info	*info,
1068 				iw_handler		handler)
1069 {
1070 	const struct iw_ioctl_description *descr;
1071 	struct compat_iw_point *iwp_compat;
1072 	struct iw_point iwp;
1073 	int err;
1074 
1075 	descr = standard_ioctl + IW_IOCTL_IDX(cmd);
1076 
1077 	if (descr->header_type != IW_HEADER_TYPE_POINT)
1078 		return ioctl_standard_call(dev, iwr, cmd, info, handler);
1079 
1080 	iwp_compat = (struct compat_iw_point *) &iwr->u.data;
1081 	iwp.pointer = compat_ptr(iwp_compat->pointer);
1082 	iwp.length = iwp_compat->length;
1083 	iwp.flags = iwp_compat->flags;
1084 
1085 	err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
1086 
1087 	iwp_compat->pointer = ptr_to_compat(iwp.pointer);
1088 	iwp_compat->length = iwp.length;
1089 	iwp_compat->flags = iwp.flags;
1090 
1091 	return err;
1092 }
1093 
1094 int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
1095 			     unsigned long arg)
1096 {
1097 	void __user *argp = (void __user *)arg;
1098 	struct iw_request_info info;
1099 	struct iwreq iwr;
1100 	char *colon;
1101 	int ret;
1102 
1103 	if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
1104 		return -EFAULT;
1105 
1106 	iwr.ifr_name[IFNAMSIZ-1] = 0;
1107 	colon = strchr(iwr.ifr_name, ':');
1108 	if (colon)
1109 		*colon = 0;
1110 
1111 	info.cmd = cmd;
1112 	info.flags = IW_REQUEST_FLAG_COMPAT;
1113 
1114 	ret = wext_ioctl_dispatch(net, &iwr, cmd, &info,
1115 				  compat_standard_call,
1116 				  compat_private_call);
1117 
1118 	if (ret >= 0 &&
1119 	    IW_IS_GET(cmd) &&
1120 	    copy_to_user(argp, &iwr, sizeof(struct iwreq)))
1121 		return -EFAULT;
1122 
1123 	return ret;
1124 }
1125 #endif
1126 
1127 char *iwe_stream_add_event(struct iw_request_info *info, char *stream,
1128 			   char *ends, struct iw_event *iwe, int event_len)
1129 {
1130 	int lcp_len = iwe_stream_lcp_len(info);
1131 
1132 	event_len = iwe_stream_event_len_adjust(info, event_len);
1133 
1134 	/* Check if it's possible */
1135 	if (likely((stream + event_len) < ends)) {
1136 		iwe->len = event_len;
1137 		/* Beware of alignement issues on 64 bits */
1138 		memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
1139 		memcpy(stream + lcp_len, &iwe->u,
1140 		       event_len - lcp_len);
1141 		stream += event_len;
1142 	}
1143 
1144 	return stream;
1145 }
1146 EXPORT_SYMBOL(iwe_stream_add_event);
1147 
1148 char *iwe_stream_add_point(struct iw_request_info *info, char *stream,
1149 			   char *ends, struct iw_event *iwe, char *extra)
1150 {
1151 	int event_len = iwe_stream_point_len(info) + iwe->u.data.length;
1152 	int point_len = iwe_stream_point_len(info);
1153 	int lcp_len   = iwe_stream_lcp_len(info);
1154 
1155 	/* Check if it's possible */
1156 	if (likely((stream + event_len) < ends)) {
1157 		iwe->len = event_len;
1158 		memcpy(stream, (char *) iwe, IW_EV_LCP_PK_LEN);
1159 		memcpy(stream + lcp_len,
1160 		       ((char *) &iwe->u) + IW_EV_POINT_OFF,
1161 		       IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
1162 		if (iwe->u.data.length && extra)
1163 			memcpy(stream + point_len, extra, iwe->u.data.length);
1164 		stream += event_len;
1165 	}
1166 
1167 	return stream;
1168 }
1169 EXPORT_SYMBOL(iwe_stream_add_point);
1170 
1171 char *iwe_stream_add_value(struct iw_request_info *info, char *event,
1172 			   char *value, char *ends, struct iw_event *iwe,
1173 			   int event_len)
1174 {
1175 	int lcp_len = iwe_stream_lcp_len(info);
1176 
1177 	/* Don't duplicate LCP */
1178 	event_len -= IW_EV_LCP_LEN;
1179 
1180 	/* Check if it's possible */
1181 	if (likely((value + event_len) < ends)) {
1182 		/* Add new value */
1183 		memcpy(value, &iwe->u, event_len);
1184 		value += event_len;
1185 		/* Patch LCP */
1186 		iwe->len = value - event;
1187 		memcpy(event, (char *) iwe, lcp_len);
1188 	}
1189 
1190 	return value;
1191 }
1192 EXPORT_SYMBOL(iwe_stream_add_value);
1193