xref: /linux/net/core/dev_ioctl.c (revision 995231c820e3bd3633cb38bf4ea6f2541e1da331)
1 #include <linux/kmod.h>
2 #include <linux/netdevice.h>
3 #include <linux/etherdevice.h>
4 #include <linux/rtnetlink.h>
5 #include <linux/net_tstamp.h>
6 #include <linux/wireless.h>
7 #include <net/wext.h>
8 
9 /*
10  *	Map an interface index to its name (SIOCGIFNAME)
11  */
12 
13 /*
14  *	We need this ioctl for efficient implementation of the
15  *	if_indextoname() function required by the IPv6 API.  Without
16  *	it, we would have to search all the interfaces to find a
17  *	match.  --pb
18  */
19 
20 static int dev_ifname(struct net *net, struct ifreq __user *arg)
21 {
22 	struct ifreq ifr;
23 	int error;
24 
25 	/*
26 	 *	Fetch the caller's info block.
27 	 */
28 
29 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
30 		return -EFAULT;
31 	ifr.ifr_name[IFNAMSIZ-1] = 0;
32 
33 	error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
34 	if (error)
35 		return error;
36 
37 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
38 		return -EFAULT;
39 	return 0;
40 }
41 
42 static gifconf_func_t *gifconf_list[NPROTO];
43 
44 /**
45  *	register_gifconf	-	register a SIOCGIF handler
46  *	@family: Address family
47  *	@gifconf: Function handler
48  *
49  *	Register protocol dependent address dumping routines. The handler
50  *	that is passed must not be freed or reused until it has been replaced
51  *	by another handler.
52  */
53 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
54 {
55 	if (family >= NPROTO)
56 		return -EINVAL;
57 	gifconf_list[family] = gifconf;
58 	return 0;
59 }
60 EXPORT_SYMBOL(register_gifconf);
61 
62 /*
63  *	Perform a SIOCGIFCONF call. This structure will change
64  *	size eventually, and there is nothing I can do about it.
65  *	Thus we will need a 'compatibility mode'.
66  */
67 
68 static int dev_ifconf(struct net *net, char __user *arg)
69 {
70 	struct ifconf ifc;
71 	struct net_device *dev;
72 	char __user *pos;
73 	int len;
74 	int total;
75 	int i;
76 
77 	/*
78 	 *	Fetch the caller's info block.
79 	 */
80 
81 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
82 		return -EFAULT;
83 
84 	pos = ifc.ifc_buf;
85 	len = ifc.ifc_len;
86 
87 	/*
88 	 *	Loop over the interfaces, and write an info block for each.
89 	 */
90 
91 	total = 0;
92 	for_each_netdev(net, dev) {
93 		for (i = 0; i < NPROTO; i++) {
94 			if (gifconf_list[i]) {
95 				int done;
96 				if (!pos)
97 					done = gifconf_list[i](dev, NULL, 0);
98 				else
99 					done = gifconf_list[i](dev, pos + total,
100 							       len - total);
101 				if (done < 0)
102 					return -EFAULT;
103 				total += done;
104 			}
105 		}
106 	}
107 
108 	/*
109 	 *	All done.  Write the updated control block back to the caller.
110 	 */
111 	ifc.ifc_len = total;
112 
113 	/*
114 	 * 	Both BSD and Solaris return 0 here, so we do too.
115 	 */
116 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
117 }
118 
119 /*
120  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
121  */
122 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
123 {
124 	int err;
125 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
126 
127 	if (!dev)
128 		return -ENODEV;
129 
130 	switch (cmd) {
131 	case SIOCGIFFLAGS:	/* Get interface flags */
132 		ifr->ifr_flags = (short) dev_get_flags(dev);
133 		return 0;
134 
135 	case SIOCGIFMETRIC:	/* Get the metric on the interface
136 				   (currently unused) */
137 		ifr->ifr_metric = 0;
138 		return 0;
139 
140 	case SIOCGIFMTU:	/* Get the MTU of a device */
141 		ifr->ifr_mtu = dev->mtu;
142 		return 0;
143 
144 	case SIOCGIFHWADDR:
145 		if (!dev->addr_len)
146 			memset(ifr->ifr_hwaddr.sa_data, 0,
147 			       sizeof(ifr->ifr_hwaddr.sa_data));
148 		else
149 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
150 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
151 				   (size_t)dev->addr_len));
152 		ifr->ifr_hwaddr.sa_family = dev->type;
153 		return 0;
154 
155 	case SIOCGIFSLAVE:
156 		err = -EINVAL;
157 		break;
158 
159 	case SIOCGIFMAP:
160 		ifr->ifr_map.mem_start = dev->mem_start;
161 		ifr->ifr_map.mem_end   = dev->mem_end;
162 		ifr->ifr_map.base_addr = dev->base_addr;
163 		ifr->ifr_map.irq       = dev->irq;
164 		ifr->ifr_map.dma       = dev->dma;
165 		ifr->ifr_map.port      = dev->if_port;
166 		return 0;
167 
168 	case SIOCGIFINDEX:
169 		ifr->ifr_ifindex = dev->ifindex;
170 		return 0;
171 
172 	case SIOCGIFTXQLEN:
173 		ifr->ifr_qlen = dev->tx_queue_len;
174 		return 0;
175 
176 	default:
177 		/* dev_ioctl() should ensure this case
178 		 * is never reached
179 		 */
180 		WARN_ON(1);
181 		err = -ENOTTY;
182 		break;
183 
184 	}
185 	return err;
186 }
187 
188 static int net_hwtstamp_validate(struct ifreq *ifr)
189 {
190 	struct hwtstamp_config cfg;
191 	enum hwtstamp_tx_types tx_type;
192 	enum hwtstamp_rx_filters rx_filter;
193 	int tx_type_valid = 0;
194 	int rx_filter_valid = 0;
195 
196 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
197 		return -EFAULT;
198 
199 	if (cfg.flags) /* reserved for future extensions */
200 		return -EINVAL;
201 
202 	tx_type = cfg.tx_type;
203 	rx_filter = cfg.rx_filter;
204 
205 	switch (tx_type) {
206 	case HWTSTAMP_TX_OFF:
207 	case HWTSTAMP_TX_ON:
208 	case HWTSTAMP_TX_ONESTEP_SYNC:
209 		tx_type_valid = 1;
210 		break;
211 	}
212 
213 	switch (rx_filter) {
214 	case HWTSTAMP_FILTER_NONE:
215 	case HWTSTAMP_FILTER_ALL:
216 	case HWTSTAMP_FILTER_SOME:
217 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
219 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
220 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
222 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
223 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
225 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
226 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
227 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
228 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
229 	case HWTSTAMP_FILTER_NTP_ALL:
230 		rx_filter_valid = 1;
231 		break;
232 	}
233 
234 	if (!tx_type_valid || !rx_filter_valid)
235 		return -ERANGE;
236 
237 	return 0;
238 }
239 
240 /*
241  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
242  */
243 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
244 {
245 	int err;
246 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
247 	const struct net_device_ops *ops;
248 
249 	if (!dev)
250 		return -ENODEV;
251 
252 	ops = dev->netdev_ops;
253 
254 	switch (cmd) {
255 	case SIOCSIFFLAGS:	/* Set interface flags */
256 		return dev_change_flags(dev, ifr->ifr_flags);
257 
258 	case SIOCSIFMETRIC:	/* Set the metric on the interface
259 				   (currently unused) */
260 		return -EOPNOTSUPP;
261 
262 	case SIOCSIFMTU:	/* Set the MTU of a device */
263 		return dev_set_mtu(dev, ifr->ifr_mtu);
264 
265 	case SIOCSIFHWADDR:
266 		if (dev->addr_len > sizeof(struct sockaddr))
267 			return -EINVAL;
268 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
269 
270 	case SIOCSIFHWBROADCAST:
271 		if (ifr->ifr_hwaddr.sa_family != dev->type)
272 			return -EINVAL;
273 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
274 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
275 			   (size_t)dev->addr_len));
276 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
277 		return 0;
278 
279 	case SIOCSIFMAP:
280 		if (ops->ndo_set_config) {
281 			if (!netif_device_present(dev))
282 				return -ENODEV;
283 			return ops->ndo_set_config(dev, &ifr->ifr_map);
284 		}
285 		return -EOPNOTSUPP;
286 
287 	case SIOCADDMULTI:
288 		if (!ops->ndo_set_rx_mode ||
289 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
290 			return -EINVAL;
291 		if (!netif_device_present(dev))
292 			return -ENODEV;
293 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
294 
295 	case SIOCDELMULTI:
296 		if (!ops->ndo_set_rx_mode ||
297 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
298 			return -EINVAL;
299 		if (!netif_device_present(dev))
300 			return -ENODEV;
301 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
302 
303 	case SIOCSIFTXQLEN:
304 		if (ifr->ifr_qlen < 0)
305 			return -EINVAL;
306 		if (dev->tx_queue_len ^ ifr->ifr_qlen) {
307 			unsigned int orig_len = dev->tx_queue_len;
308 
309 			dev->tx_queue_len = ifr->ifr_qlen;
310 			err = call_netdevice_notifiers(
311 					NETDEV_CHANGE_TX_QUEUE_LEN, dev);
312 			err = notifier_to_errno(err);
313 			if (err) {
314 				dev->tx_queue_len = orig_len;
315 				return err;
316 			}
317 		}
318 		return 0;
319 
320 	case SIOCSIFNAME:
321 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
322 		return dev_change_name(dev, ifr->ifr_newname);
323 
324 	case SIOCSHWTSTAMP:
325 		err = net_hwtstamp_validate(ifr);
326 		if (err)
327 			return err;
328 		/* fall through */
329 
330 	/*
331 	 *	Unknown or private ioctl
332 	 */
333 	default:
334 		if ((cmd >= SIOCDEVPRIVATE &&
335 		    cmd <= SIOCDEVPRIVATE + 15) ||
336 		    cmd == SIOCBONDENSLAVE ||
337 		    cmd == SIOCBONDRELEASE ||
338 		    cmd == SIOCBONDSETHWADDR ||
339 		    cmd == SIOCBONDSLAVEINFOQUERY ||
340 		    cmd == SIOCBONDINFOQUERY ||
341 		    cmd == SIOCBONDCHANGEACTIVE ||
342 		    cmd == SIOCGMIIPHY ||
343 		    cmd == SIOCGMIIREG ||
344 		    cmd == SIOCSMIIREG ||
345 		    cmd == SIOCBRADDIF ||
346 		    cmd == SIOCBRDELIF ||
347 		    cmd == SIOCSHWTSTAMP ||
348 		    cmd == SIOCGHWTSTAMP ||
349 		    cmd == SIOCWANDEV) {
350 			err = -EOPNOTSUPP;
351 			if (ops->ndo_do_ioctl) {
352 				if (netif_device_present(dev))
353 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
354 				else
355 					err = -ENODEV;
356 			}
357 		} else
358 			err = -EINVAL;
359 
360 	}
361 	return err;
362 }
363 
364 /**
365  *	dev_load 	- load a network module
366  *	@net: the applicable net namespace
367  *	@name: name of interface
368  *
369  *	If a network interface is not present and the process has suitable
370  *	privileges this function loads the module. If module loading is not
371  *	available in this kernel then it becomes a nop.
372  */
373 
374 void dev_load(struct net *net, const char *name)
375 {
376 	struct net_device *dev;
377 	int no_module;
378 
379 	rcu_read_lock();
380 	dev = dev_get_by_name_rcu(net, name);
381 	rcu_read_unlock();
382 
383 	no_module = !dev;
384 	if (no_module && capable(CAP_NET_ADMIN))
385 		no_module = request_module("netdev-%s", name);
386 	if (no_module && capable(CAP_SYS_MODULE))
387 		request_module("%s", name);
388 }
389 EXPORT_SYMBOL(dev_load);
390 
391 /*
392  *	This function handles all "interface"-type I/O control requests. The actual
393  *	'doing' part of this is dev_ifsioc above.
394  */
395 
396 /**
397  *	dev_ioctl	-	network device ioctl
398  *	@net: the applicable net namespace
399  *	@cmd: command to issue
400  *	@arg: pointer to a struct ifreq in user space
401  *
402  *	Issue ioctl functions to devices. This is normally called by the
403  *	user space syscall interfaces but can sometimes be useful for
404  *	other purposes. The return value is the return from the syscall if
405  *	positive or a negative errno code on error.
406  */
407 
408 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
409 {
410 	struct ifreq ifr;
411 	int ret;
412 	char *colon;
413 
414 	/* One special case: SIOCGIFCONF takes ifconf argument
415 	   and requires shared lock, because it sleeps writing
416 	   to user space.
417 	 */
418 
419 	if (cmd == SIOCGIFCONF) {
420 		rtnl_lock();
421 		ret = dev_ifconf(net, (char __user *) arg);
422 		rtnl_unlock();
423 		return ret;
424 	}
425 	if (cmd == SIOCGIFNAME)
426 		return dev_ifname(net, (struct ifreq __user *)arg);
427 
428 	/*
429 	 * Take care of Wireless Extensions. Unfortunately struct iwreq
430 	 * isn't a proper subset of struct ifreq (it's 8 byte shorter)
431 	 * so we need to treat it specially, otherwise applications may
432 	 * fault if the struct they're passing happens to land at the
433 	 * end of a mapped page.
434 	 */
435 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
436 		struct iwreq iwr;
437 
438 		if (copy_from_user(&iwr, arg, sizeof(iwr)))
439 			return -EFAULT;
440 
441 		iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
442 
443 		return wext_handle_ioctl(net, &iwr, cmd, arg);
444 	}
445 
446 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
447 		return -EFAULT;
448 
449 	ifr.ifr_name[IFNAMSIZ-1] = 0;
450 
451 	colon = strchr(ifr.ifr_name, ':');
452 	if (colon)
453 		*colon = 0;
454 
455 	/*
456 	 *	See which interface the caller is talking about.
457 	 */
458 
459 	switch (cmd) {
460 	/*
461 	 *	These ioctl calls:
462 	 *	- can be done by all.
463 	 *	- atomic and do not require locking.
464 	 *	- return a value
465 	 */
466 	case SIOCGIFFLAGS:
467 	case SIOCGIFMETRIC:
468 	case SIOCGIFMTU:
469 	case SIOCGIFHWADDR:
470 	case SIOCGIFSLAVE:
471 	case SIOCGIFMAP:
472 	case SIOCGIFINDEX:
473 	case SIOCGIFTXQLEN:
474 		dev_load(net, ifr.ifr_name);
475 		rcu_read_lock();
476 		ret = dev_ifsioc_locked(net, &ifr, cmd);
477 		rcu_read_unlock();
478 		if (!ret) {
479 			if (colon)
480 				*colon = ':';
481 			if (copy_to_user(arg, &ifr,
482 					 sizeof(struct ifreq)))
483 				ret = -EFAULT;
484 		}
485 		return ret;
486 
487 	case SIOCETHTOOL:
488 		dev_load(net, ifr.ifr_name);
489 		rtnl_lock();
490 		ret = dev_ethtool(net, &ifr);
491 		rtnl_unlock();
492 		if (!ret) {
493 			if (colon)
494 				*colon = ':';
495 			if (copy_to_user(arg, &ifr,
496 					 sizeof(struct ifreq)))
497 				ret = -EFAULT;
498 		}
499 		return ret;
500 
501 	/*
502 	 *	These ioctl calls:
503 	 *	- require superuser power.
504 	 *	- require strict serialization.
505 	 *	- return a value
506 	 */
507 	case SIOCGMIIPHY:
508 	case SIOCGMIIREG:
509 	case SIOCSIFNAME:
510 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
511 			return -EPERM;
512 		dev_load(net, ifr.ifr_name);
513 		rtnl_lock();
514 		ret = dev_ifsioc(net, &ifr, cmd);
515 		rtnl_unlock();
516 		if (!ret) {
517 			if (colon)
518 				*colon = ':';
519 			if (copy_to_user(arg, &ifr,
520 					 sizeof(struct ifreq)))
521 				ret = -EFAULT;
522 		}
523 		return ret;
524 
525 	/*
526 	 *	These ioctl calls:
527 	 *	- require superuser power.
528 	 *	- require strict serialization.
529 	 *	- do not return a value
530 	 */
531 	case SIOCSIFMAP:
532 	case SIOCSIFTXQLEN:
533 		if (!capable(CAP_NET_ADMIN))
534 			return -EPERM;
535 		/* fall through */
536 	/*
537 	 *	These ioctl calls:
538 	 *	- require local superuser power.
539 	 *	- require strict serialization.
540 	 *	- do not return a value
541 	 */
542 	case SIOCSIFFLAGS:
543 	case SIOCSIFMETRIC:
544 	case SIOCSIFMTU:
545 	case SIOCSIFHWADDR:
546 	case SIOCSIFSLAVE:
547 	case SIOCADDMULTI:
548 	case SIOCDELMULTI:
549 	case SIOCSIFHWBROADCAST:
550 	case SIOCSMIIREG:
551 	case SIOCBONDENSLAVE:
552 	case SIOCBONDRELEASE:
553 	case SIOCBONDSETHWADDR:
554 	case SIOCBONDCHANGEACTIVE:
555 	case SIOCBRADDIF:
556 	case SIOCBRDELIF:
557 	case SIOCSHWTSTAMP:
558 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
559 			return -EPERM;
560 		/* fall through */
561 	case SIOCBONDSLAVEINFOQUERY:
562 	case SIOCBONDINFOQUERY:
563 		dev_load(net, ifr.ifr_name);
564 		rtnl_lock();
565 		ret = dev_ifsioc(net, &ifr, cmd);
566 		rtnl_unlock();
567 		return ret;
568 
569 	case SIOCGIFMEM:
570 		/* Get the per device memory space. We can add this but
571 		 * currently do not support it */
572 	case SIOCSIFMEM:
573 		/* Set the per device memory buffer space.
574 		 * Not applicable in our case */
575 	case SIOCSIFLINK:
576 		return -ENOTTY;
577 
578 	/*
579 	 *	Unknown or private ioctl.
580 	 */
581 	default:
582 		if (cmd == SIOCWANDEV ||
583 		    cmd == SIOCGHWTSTAMP ||
584 		    (cmd >= SIOCDEVPRIVATE &&
585 		     cmd <= SIOCDEVPRIVATE + 15)) {
586 			dev_load(net, ifr.ifr_name);
587 			rtnl_lock();
588 			ret = dev_ifsioc(net, &ifr, cmd);
589 			rtnl_unlock();
590 			if (!ret && copy_to_user(arg, &ifr,
591 						 sizeof(struct ifreq)))
592 				ret = -EFAULT;
593 			return ret;
594 		}
595 		return -ENOTTY;
596 	}
597 }
598