xref: /linux/net/core/dev_ioctl.c (revision a3a4a816b4b194c45d0217e8b9e08b2639802cda)
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 
32 	error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
33 	if (error)
34 		return error;
35 
36 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
37 		return -EFAULT;
38 	return 0;
39 }
40 
41 static gifconf_func_t *gifconf_list[NPROTO];
42 
43 /**
44  *	register_gifconf	-	register a SIOCGIF handler
45  *	@family: Address family
46  *	@gifconf: Function handler
47  *
48  *	Register protocol dependent address dumping routines. The handler
49  *	that is passed must not be freed or reused until it has been replaced
50  *	by another handler.
51  */
52 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
53 {
54 	if (family >= NPROTO)
55 		return -EINVAL;
56 	gifconf_list[family] = gifconf;
57 	return 0;
58 }
59 EXPORT_SYMBOL(register_gifconf);
60 
61 /*
62  *	Perform a SIOCGIFCONF call. This structure will change
63  *	size eventually, and there is nothing I can do about it.
64  *	Thus we will need a 'compatibility mode'.
65  */
66 
67 static int dev_ifconf(struct net *net, char __user *arg)
68 {
69 	struct ifconf ifc;
70 	struct net_device *dev;
71 	char __user *pos;
72 	int len;
73 	int total;
74 	int i;
75 
76 	/*
77 	 *	Fetch the caller's info block.
78 	 */
79 
80 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
81 		return -EFAULT;
82 
83 	pos = ifc.ifc_buf;
84 	len = ifc.ifc_len;
85 
86 	/*
87 	 *	Loop over the interfaces, and write an info block for each.
88 	 */
89 
90 	total = 0;
91 	for_each_netdev(net, dev) {
92 		for (i = 0; i < NPROTO; i++) {
93 			if (gifconf_list[i]) {
94 				int done;
95 				if (!pos)
96 					done = gifconf_list[i](dev, NULL, 0);
97 				else
98 					done = gifconf_list[i](dev, pos + total,
99 							       len - total);
100 				if (done < 0)
101 					return -EFAULT;
102 				total += done;
103 			}
104 		}
105 	}
106 
107 	/*
108 	 *	All done.  Write the updated control block back to the caller.
109 	 */
110 	ifc.ifc_len = total;
111 
112 	/*
113 	 * 	Both BSD and Solaris return 0 here, so we do too.
114 	 */
115 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
116 }
117 
118 /*
119  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
120  */
121 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
122 {
123 	int err;
124 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
125 
126 	if (!dev)
127 		return -ENODEV;
128 
129 	switch (cmd) {
130 	case SIOCGIFFLAGS:	/* Get interface flags */
131 		ifr->ifr_flags = (short) dev_get_flags(dev);
132 		return 0;
133 
134 	case SIOCGIFMETRIC:	/* Get the metric on the interface
135 				   (currently unused) */
136 		ifr->ifr_metric = 0;
137 		return 0;
138 
139 	case SIOCGIFMTU:	/* Get the MTU of a device */
140 		ifr->ifr_mtu = dev->mtu;
141 		return 0;
142 
143 	case SIOCGIFHWADDR:
144 		if (!dev->addr_len)
145 			memset(ifr->ifr_hwaddr.sa_data, 0,
146 			       sizeof(ifr->ifr_hwaddr.sa_data));
147 		else
148 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
149 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
150 				   (size_t)dev->addr_len));
151 		ifr->ifr_hwaddr.sa_family = dev->type;
152 		return 0;
153 
154 	case SIOCGIFSLAVE:
155 		err = -EINVAL;
156 		break;
157 
158 	case SIOCGIFMAP:
159 		ifr->ifr_map.mem_start = dev->mem_start;
160 		ifr->ifr_map.mem_end   = dev->mem_end;
161 		ifr->ifr_map.base_addr = dev->base_addr;
162 		ifr->ifr_map.irq       = dev->irq;
163 		ifr->ifr_map.dma       = dev->dma;
164 		ifr->ifr_map.port      = dev->if_port;
165 		return 0;
166 
167 	case SIOCGIFINDEX:
168 		ifr->ifr_ifindex = dev->ifindex;
169 		return 0;
170 
171 	case SIOCGIFTXQLEN:
172 		ifr->ifr_qlen = dev->tx_queue_len;
173 		return 0;
174 
175 	default:
176 		/* dev_ioctl() should ensure this case
177 		 * is never reached
178 		 */
179 		WARN_ON(1);
180 		err = -ENOTTY;
181 		break;
182 
183 	}
184 	return err;
185 }
186 
187 static int net_hwtstamp_validate(struct ifreq *ifr)
188 {
189 	struct hwtstamp_config cfg;
190 	enum hwtstamp_tx_types tx_type;
191 	enum hwtstamp_rx_filters rx_filter;
192 	int tx_type_valid = 0;
193 	int rx_filter_valid = 0;
194 
195 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
196 		return -EFAULT;
197 
198 	if (cfg.flags) /* reserved for future extensions */
199 		return -EINVAL;
200 
201 	tx_type = cfg.tx_type;
202 	rx_filter = cfg.rx_filter;
203 
204 	switch (tx_type) {
205 	case HWTSTAMP_TX_OFF:
206 	case HWTSTAMP_TX_ON:
207 	case HWTSTAMP_TX_ONESTEP_SYNC:
208 		tx_type_valid = 1;
209 		break;
210 	}
211 
212 	switch (rx_filter) {
213 	case HWTSTAMP_FILTER_NONE:
214 	case HWTSTAMP_FILTER_ALL:
215 	case HWTSTAMP_FILTER_SOME:
216 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
217 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
219 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
220 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
222 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
223 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
225 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
226 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
227 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
228 		rx_filter_valid = 1;
229 		break;
230 	}
231 
232 	if (!tx_type_valid || !rx_filter_valid)
233 		return -ERANGE;
234 
235 	return 0;
236 }
237 
238 /*
239  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
240  */
241 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
242 {
243 	int err;
244 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
245 	const struct net_device_ops *ops;
246 
247 	if (!dev)
248 		return -ENODEV;
249 
250 	ops = dev->netdev_ops;
251 
252 	switch (cmd) {
253 	case SIOCSIFFLAGS:	/* Set interface flags */
254 		return dev_change_flags(dev, ifr->ifr_flags);
255 
256 	case SIOCSIFMETRIC:	/* Set the metric on the interface
257 				   (currently unused) */
258 		return -EOPNOTSUPP;
259 
260 	case SIOCSIFMTU:	/* Set the MTU of a device */
261 		return dev_set_mtu(dev, ifr->ifr_mtu);
262 
263 	case SIOCSIFHWADDR:
264 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
265 
266 	case SIOCSIFHWBROADCAST:
267 		if (ifr->ifr_hwaddr.sa_family != dev->type)
268 			return -EINVAL;
269 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
270 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
271 			   (size_t)dev->addr_len));
272 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
273 		return 0;
274 
275 	case SIOCSIFMAP:
276 		if (ops->ndo_set_config) {
277 			if (!netif_device_present(dev))
278 				return -ENODEV;
279 			return ops->ndo_set_config(dev, &ifr->ifr_map);
280 		}
281 		return -EOPNOTSUPP;
282 
283 	case SIOCADDMULTI:
284 		if (!ops->ndo_set_rx_mode ||
285 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
286 			return -EINVAL;
287 		if (!netif_device_present(dev))
288 			return -ENODEV;
289 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
290 
291 	case SIOCDELMULTI:
292 		if (!ops->ndo_set_rx_mode ||
293 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
294 			return -EINVAL;
295 		if (!netif_device_present(dev))
296 			return -ENODEV;
297 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
298 
299 	case SIOCSIFTXQLEN:
300 		if (ifr->ifr_qlen < 0)
301 			return -EINVAL;
302 		dev->tx_queue_len = ifr->ifr_qlen;
303 		return 0;
304 
305 	case SIOCSIFNAME:
306 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
307 		return dev_change_name(dev, ifr->ifr_newname);
308 
309 	case SIOCSHWTSTAMP:
310 		err = net_hwtstamp_validate(ifr);
311 		if (err)
312 			return err;
313 		/* fall through */
314 
315 	/*
316 	 *	Unknown or private ioctl
317 	 */
318 	default:
319 		if ((cmd >= SIOCDEVPRIVATE &&
320 		    cmd <= SIOCDEVPRIVATE + 15) ||
321 		    cmd == SIOCBONDENSLAVE ||
322 		    cmd == SIOCBONDRELEASE ||
323 		    cmd == SIOCBONDSETHWADDR ||
324 		    cmd == SIOCBONDSLAVEINFOQUERY ||
325 		    cmd == SIOCBONDINFOQUERY ||
326 		    cmd == SIOCBONDCHANGEACTIVE ||
327 		    cmd == SIOCGMIIPHY ||
328 		    cmd == SIOCGMIIREG ||
329 		    cmd == SIOCSMIIREG ||
330 		    cmd == SIOCBRADDIF ||
331 		    cmd == SIOCBRDELIF ||
332 		    cmd == SIOCSHWTSTAMP ||
333 		    cmd == SIOCGHWTSTAMP ||
334 		    cmd == SIOCWANDEV) {
335 			err = -EOPNOTSUPP;
336 			if (ops->ndo_do_ioctl) {
337 				if (netif_device_present(dev))
338 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
339 				else
340 					err = -ENODEV;
341 			}
342 		} else
343 			err = -EINVAL;
344 
345 	}
346 	return err;
347 }
348 
349 /**
350  *	dev_load 	- load a network module
351  *	@net: the applicable net namespace
352  *	@name: name of interface
353  *
354  *	If a network interface is not present and the process has suitable
355  *	privileges this function loads the module. If module loading is not
356  *	available in this kernel then it becomes a nop.
357  */
358 
359 void dev_load(struct net *net, const char *name)
360 {
361 	struct net_device *dev;
362 	int no_module;
363 
364 	rcu_read_lock();
365 	dev = dev_get_by_name_rcu(net, name);
366 	rcu_read_unlock();
367 
368 	no_module = !dev;
369 	if (no_module && capable(CAP_NET_ADMIN))
370 		no_module = request_module("netdev-%s", name);
371 	if (no_module && capable(CAP_SYS_MODULE))
372 		request_module("%s", name);
373 }
374 EXPORT_SYMBOL(dev_load);
375 
376 /*
377  *	This function handles all "interface"-type I/O control requests. The actual
378  *	'doing' part of this is dev_ifsioc above.
379  */
380 
381 /**
382  *	dev_ioctl	-	network device ioctl
383  *	@net: the applicable net namespace
384  *	@cmd: command to issue
385  *	@arg: pointer to a struct ifreq in user space
386  *
387  *	Issue ioctl functions to devices. This is normally called by the
388  *	user space syscall interfaces but can sometimes be useful for
389  *	other purposes. The return value is the return from the syscall if
390  *	positive or a negative errno code on error.
391  */
392 
393 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
394 {
395 	struct ifreq ifr;
396 	int ret;
397 	char *colon;
398 
399 	/* One special case: SIOCGIFCONF takes ifconf argument
400 	   and requires shared lock, because it sleeps writing
401 	   to user space.
402 	 */
403 
404 	if (cmd == SIOCGIFCONF) {
405 		rtnl_lock();
406 		ret = dev_ifconf(net, (char __user *) arg);
407 		rtnl_unlock();
408 		return ret;
409 	}
410 	if (cmd == SIOCGIFNAME)
411 		return dev_ifname(net, (struct ifreq __user *)arg);
412 
413 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
414 		return -EFAULT;
415 
416 	ifr.ifr_name[IFNAMSIZ-1] = 0;
417 
418 	colon = strchr(ifr.ifr_name, ':');
419 	if (colon)
420 		*colon = 0;
421 
422 	/*
423 	 *	See which interface the caller is talking about.
424 	 */
425 
426 	switch (cmd) {
427 	/*
428 	 *	These ioctl calls:
429 	 *	- can be done by all.
430 	 *	- atomic and do not require locking.
431 	 *	- return a value
432 	 */
433 	case SIOCGIFFLAGS:
434 	case SIOCGIFMETRIC:
435 	case SIOCGIFMTU:
436 	case SIOCGIFHWADDR:
437 	case SIOCGIFSLAVE:
438 	case SIOCGIFMAP:
439 	case SIOCGIFINDEX:
440 	case SIOCGIFTXQLEN:
441 		dev_load(net, ifr.ifr_name);
442 		rcu_read_lock();
443 		ret = dev_ifsioc_locked(net, &ifr, cmd);
444 		rcu_read_unlock();
445 		if (!ret) {
446 			if (colon)
447 				*colon = ':';
448 			if (copy_to_user(arg, &ifr,
449 					 sizeof(struct ifreq)))
450 				ret = -EFAULT;
451 		}
452 		return ret;
453 
454 	case SIOCETHTOOL:
455 		dev_load(net, ifr.ifr_name);
456 		rtnl_lock();
457 		ret = dev_ethtool(net, &ifr);
458 		rtnl_unlock();
459 		if (!ret) {
460 			if (colon)
461 				*colon = ':';
462 			if (copy_to_user(arg, &ifr,
463 					 sizeof(struct ifreq)))
464 				ret = -EFAULT;
465 		}
466 		return ret;
467 
468 	/*
469 	 *	These ioctl calls:
470 	 *	- require superuser power.
471 	 *	- require strict serialization.
472 	 *	- return a value
473 	 */
474 	case SIOCGMIIPHY:
475 	case SIOCGMIIREG:
476 	case SIOCSIFNAME:
477 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
478 			return -EPERM;
479 		dev_load(net, ifr.ifr_name);
480 		rtnl_lock();
481 		ret = dev_ifsioc(net, &ifr, cmd);
482 		rtnl_unlock();
483 		if (!ret) {
484 			if (colon)
485 				*colon = ':';
486 			if (copy_to_user(arg, &ifr,
487 					 sizeof(struct ifreq)))
488 				ret = -EFAULT;
489 		}
490 		return ret;
491 
492 	/*
493 	 *	These ioctl calls:
494 	 *	- require superuser power.
495 	 *	- require strict serialization.
496 	 *	- do not return a value
497 	 */
498 	case SIOCSIFMAP:
499 	case SIOCSIFTXQLEN:
500 		if (!capable(CAP_NET_ADMIN))
501 			return -EPERM;
502 		/* fall through */
503 	/*
504 	 *	These ioctl calls:
505 	 *	- require local superuser power.
506 	 *	- require strict serialization.
507 	 *	- do not return a value
508 	 */
509 	case SIOCSIFFLAGS:
510 	case SIOCSIFMETRIC:
511 	case SIOCSIFMTU:
512 	case SIOCSIFHWADDR:
513 	case SIOCSIFSLAVE:
514 	case SIOCADDMULTI:
515 	case SIOCDELMULTI:
516 	case SIOCSIFHWBROADCAST:
517 	case SIOCSMIIREG:
518 	case SIOCBONDENSLAVE:
519 	case SIOCBONDRELEASE:
520 	case SIOCBONDSETHWADDR:
521 	case SIOCBONDCHANGEACTIVE:
522 	case SIOCBRADDIF:
523 	case SIOCBRDELIF:
524 	case SIOCSHWTSTAMP:
525 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
526 			return -EPERM;
527 		/* fall through */
528 	case SIOCBONDSLAVEINFOQUERY:
529 	case SIOCBONDINFOQUERY:
530 		dev_load(net, ifr.ifr_name);
531 		rtnl_lock();
532 		ret = dev_ifsioc(net, &ifr, cmd);
533 		rtnl_unlock();
534 		return ret;
535 
536 	case SIOCGIFMEM:
537 		/* Get the per device memory space. We can add this but
538 		 * currently do not support it */
539 	case SIOCSIFMEM:
540 		/* Set the per device memory buffer space.
541 		 * Not applicable in our case */
542 	case SIOCSIFLINK:
543 		return -ENOTTY;
544 
545 	/*
546 	 *	Unknown or private ioctl.
547 	 */
548 	default:
549 		if (cmd == SIOCWANDEV ||
550 		    cmd == SIOCGHWTSTAMP ||
551 		    (cmd >= SIOCDEVPRIVATE &&
552 		     cmd <= SIOCDEVPRIVATE + 15)) {
553 			dev_load(net, ifr.ifr_name);
554 			rtnl_lock();
555 			ret = dev_ifsioc(net, &ifr, cmd);
556 			rtnl_unlock();
557 			if (!ret && copy_to_user(arg, &ifr,
558 						 sizeof(struct ifreq)))
559 				ret = -EFAULT;
560 			return ret;
561 		}
562 		/* Take care of Wireless Extensions */
563 		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
564 			return wext_handle_ioctl(net, &ifr, cmd, arg);
565 		return -ENOTTY;
566 	}
567 }
568