xref: /openbmc/linux/net/core/dev_ioctl.c (revision f35e839a)
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 net_device *dev;
23 	struct ifreq ifr;
24 	unsigned seq;
25 
26 	/*
27 	 *	Fetch the caller's info block.
28 	 */
29 
30 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
31 		return -EFAULT;
32 
33 retry:
34 	seq = read_seqcount_begin(&devnet_rename_seq);
35 	rcu_read_lock();
36 	dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
37 	if (!dev) {
38 		rcu_read_unlock();
39 		return -ENODEV;
40 	}
41 
42 	strcpy(ifr.ifr_name, dev->name);
43 	rcu_read_unlock();
44 	if (read_seqcount_retry(&devnet_rename_seq, seq))
45 		goto retry;
46 
47 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
48 		return -EFAULT;
49 	return 0;
50 }
51 
52 static gifconf_func_t *gifconf_list[NPROTO];
53 
54 /**
55  *	register_gifconf	-	register a SIOCGIF handler
56  *	@family: Address family
57  *	@gifconf: Function handler
58  *
59  *	Register protocol dependent address dumping routines. The handler
60  *	that is passed must not be freed or reused until it has been replaced
61  *	by another handler.
62  */
63 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
64 {
65 	if (family >= NPROTO)
66 		return -EINVAL;
67 	gifconf_list[family] = gifconf;
68 	return 0;
69 }
70 EXPORT_SYMBOL(register_gifconf);
71 
72 /*
73  *	Perform a SIOCGIFCONF call. This structure will change
74  *	size eventually, and there is nothing I can do about it.
75  *	Thus we will need a 'compatibility mode'.
76  */
77 
78 static int dev_ifconf(struct net *net, char __user *arg)
79 {
80 	struct ifconf ifc;
81 	struct net_device *dev;
82 	char __user *pos;
83 	int len;
84 	int total;
85 	int i;
86 
87 	/*
88 	 *	Fetch the caller's info block.
89 	 */
90 
91 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
92 		return -EFAULT;
93 
94 	pos = ifc.ifc_buf;
95 	len = ifc.ifc_len;
96 
97 	/*
98 	 *	Loop over the interfaces, and write an info block for each.
99 	 */
100 
101 	total = 0;
102 	for_each_netdev(net, dev) {
103 		for (i = 0; i < NPROTO; i++) {
104 			if (gifconf_list[i]) {
105 				int done;
106 				if (!pos)
107 					done = gifconf_list[i](dev, NULL, 0);
108 				else
109 					done = gifconf_list[i](dev, pos + total,
110 							       len - total);
111 				if (done < 0)
112 					return -EFAULT;
113 				total += done;
114 			}
115 		}
116 	}
117 
118 	/*
119 	 *	All done.  Write the updated control block back to the caller.
120 	 */
121 	ifc.ifc_len = total;
122 
123 	/*
124 	 * 	Both BSD and Solaris return 0 here, so we do too.
125 	 */
126 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
127 }
128 
129 /*
130  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
131  */
132 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
133 {
134 	int err;
135 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
136 
137 	if (!dev)
138 		return -ENODEV;
139 
140 	switch (cmd) {
141 	case SIOCGIFFLAGS:	/* Get interface flags */
142 		ifr->ifr_flags = (short) dev_get_flags(dev);
143 		return 0;
144 
145 	case SIOCGIFMETRIC:	/* Get the metric on the interface
146 				   (currently unused) */
147 		ifr->ifr_metric = 0;
148 		return 0;
149 
150 	case SIOCGIFMTU:	/* Get the MTU of a device */
151 		ifr->ifr_mtu = dev->mtu;
152 		return 0;
153 
154 	case SIOCGIFHWADDR:
155 		if (!dev->addr_len)
156 			memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
157 		else
158 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
159 			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
160 		ifr->ifr_hwaddr.sa_family = dev->type;
161 		return 0;
162 
163 	case SIOCGIFSLAVE:
164 		err = -EINVAL;
165 		break;
166 
167 	case SIOCGIFMAP:
168 		ifr->ifr_map.mem_start = dev->mem_start;
169 		ifr->ifr_map.mem_end   = dev->mem_end;
170 		ifr->ifr_map.base_addr = dev->base_addr;
171 		ifr->ifr_map.irq       = dev->irq;
172 		ifr->ifr_map.dma       = dev->dma;
173 		ifr->ifr_map.port      = dev->if_port;
174 		return 0;
175 
176 	case SIOCGIFINDEX:
177 		ifr->ifr_ifindex = dev->ifindex;
178 		return 0;
179 
180 	case SIOCGIFTXQLEN:
181 		ifr->ifr_qlen = dev->tx_queue_len;
182 		return 0;
183 
184 	default:
185 		/* dev_ioctl() should ensure this case
186 		 * is never reached
187 		 */
188 		WARN_ON(1);
189 		err = -ENOTTY;
190 		break;
191 
192 	}
193 	return err;
194 }
195 
196 static int net_hwtstamp_validate(struct ifreq *ifr)
197 {
198 	struct hwtstamp_config cfg;
199 	enum hwtstamp_tx_types tx_type;
200 	enum hwtstamp_rx_filters rx_filter;
201 	int tx_type_valid = 0;
202 	int rx_filter_valid = 0;
203 
204 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
205 		return -EFAULT;
206 
207 	if (cfg.flags) /* reserved for future extensions */
208 		return -EINVAL;
209 
210 	tx_type = cfg.tx_type;
211 	rx_filter = cfg.rx_filter;
212 
213 	switch (tx_type) {
214 	case HWTSTAMP_TX_OFF:
215 	case HWTSTAMP_TX_ON:
216 	case HWTSTAMP_TX_ONESTEP_SYNC:
217 		tx_type_valid = 1;
218 		break;
219 	}
220 
221 	switch (rx_filter) {
222 	case HWTSTAMP_FILTER_NONE:
223 	case HWTSTAMP_FILTER_ALL:
224 	case HWTSTAMP_FILTER_SOME:
225 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
226 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
227 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
228 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
229 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
230 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
231 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
232 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
233 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
234 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
235 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
236 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
237 		rx_filter_valid = 1;
238 		break;
239 	}
240 
241 	if (!tx_type_valid || !rx_filter_valid)
242 		return -ERANGE;
243 
244 	return 0;
245 }
246 
247 /*
248  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
249  */
250 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
251 {
252 	int err;
253 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
254 	const struct net_device_ops *ops;
255 
256 	if (!dev)
257 		return -ENODEV;
258 
259 	ops = dev->netdev_ops;
260 
261 	switch (cmd) {
262 	case SIOCSIFFLAGS:	/* Set interface flags */
263 		return dev_change_flags(dev, ifr->ifr_flags);
264 
265 	case SIOCSIFMETRIC:	/* Set the metric on the interface
266 				   (currently unused) */
267 		return -EOPNOTSUPP;
268 
269 	case SIOCSIFMTU:	/* Set the MTU of a device */
270 		return dev_set_mtu(dev, ifr->ifr_mtu);
271 
272 	case SIOCSIFHWADDR:
273 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
274 
275 	case SIOCSIFHWBROADCAST:
276 		if (ifr->ifr_hwaddr.sa_family != dev->type)
277 			return -EINVAL;
278 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
279 		       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
280 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
281 		return 0;
282 
283 	case SIOCSIFMAP:
284 		if (ops->ndo_set_config) {
285 			if (!netif_device_present(dev))
286 				return -ENODEV;
287 			return ops->ndo_set_config(dev, &ifr->ifr_map);
288 		}
289 		return -EOPNOTSUPP;
290 
291 	case SIOCADDMULTI:
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_add_global(dev, ifr->ifr_hwaddr.sa_data);
298 
299 	case SIOCDELMULTI:
300 		if (!ops->ndo_set_rx_mode ||
301 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
302 			return -EINVAL;
303 		if (!netif_device_present(dev))
304 			return -ENODEV;
305 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
306 
307 	case SIOCSIFTXQLEN:
308 		if (ifr->ifr_qlen < 0)
309 			return -EINVAL;
310 		dev->tx_queue_len = ifr->ifr_qlen;
311 		return 0;
312 
313 	case SIOCSIFNAME:
314 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
315 		return dev_change_name(dev, ifr->ifr_newname);
316 
317 	case SIOCSHWTSTAMP:
318 		err = net_hwtstamp_validate(ifr);
319 		if (err)
320 			return err;
321 		/* fall through */
322 
323 	/*
324 	 *	Unknown or private ioctl
325 	 */
326 	default:
327 		if ((cmd >= SIOCDEVPRIVATE &&
328 		    cmd <= SIOCDEVPRIVATE + 15) ||
329 		    cmd == SIOCBONDENSLAVE ||
330 		    cmd == SIOCBONDRELEASE ||
331 		    cmd == SIOCBONDSETHWADDR ||
332 		    cmd == SIOCBONDSLAVEINFOQUERY ||
333 		    cmd == SIOCBONDINFOQUERY ||
334 		    cmd == SIOCBONDCHANGEACTIVE ||
335 		    cmd == SIOCGMIIPHY ||
336 		    cmd == SIOCGMIIREG ||
337 		    cmd == SIOCSMIIREG ||
338 		    cmd == SIOCBRADDIF ||
339 		    cmd == SIOCBRDELIF ||
340 		    cmd == SIOCSHWTSTAMP ||
341 		    cmd == SIOCWANDEV) {
342 			err = -EOPNOTSUPP;
343 			if (ops->ndo_do_ioctl) {
344 				if (netif_device_present(dev))
345 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
346 				else
347 					err = -ENODEV;
348 			}
349 		} else
350 			err = -EINVAL;
351 
352 	}
353 	return err;
354 }
355 
356 /**
357  *	dev_load 	- load a network module
358  *	@net: the applicable net namespace
359  *	@name: name of interface
360  *
361  *	If a network interface is not present and the process has suitable
362  *	privileges this function loads the module. If module loading is not
363  *	available in this kernel then it becomes a nop.
364  */
365 
366 void dev_load(struct net *net, const char *name)
367 {
368 	struct net_device *dev;
369 	int no_module;
370 
371 	rcu_read_lock();
372 	dev = dev_get_by_name_rcu(net, name);
373 	rcu_read_unlock();
374 
375 	no_module = !dev;
376 	if (no_module && capable(CAP_NET_ADMIN))
377 		no_module = request_module("netdev-%s", name);
378 	if (no_module && capable(CAP_SYS_MODULE)) {
379 		if (!request_module("%s", name))
380 			pr_warn("Loading kernel module for a network device with CAP_SYS_MODULE (deprecated).  Use CAP_NET_ADMIN and alias netdev-%s instead.\n",
381 				name);
382 	}
383 }
384 EXPORT_SYMBOL(dev_load);
385 
386 /*
387  *	This function handles all "interface"-type I/O control requests. The actual
388  *	'doing' part of this is dev_ifsioc above.
389  */
390 
391 /**
392  *	dev_ioctl	-	network device ioctl
393  *	@net: the applicable net namespace
394  *	@cmd: command to issue
395  *	@arg: pointer to a struct ifreq in user space
396  *
397  *	Issue ioctl functions to devices. This is normally called by the
398  *	user space syscall interfaces but can sometimes be useful for
399  *	other purposes. The return value is the return from the syscall if
400  *	positive or a negative errno code on error.
401  */
402 
403 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
404 {
405 	struct ifreq ifr;
406 	int ret;
407 	char *colon;
408 
409 	/* One special case: SIOCGIFCONF takes ifconf argument
410 	   and requires shared lock, because it sleeps writing
411 	   to user space.
412 	 */
413 
414 	if (cmd == SIOCGIFCONF) {
415 		rtnl_lock();
416 		ret = dev_ifconf(net, (char __user *) arg);
417 		rtnl_unlock();
418 		return ret;
419 	}
420 	if (cmd == SIOCGIFNAME)
421 		return dev_ifname(net, (struct ifreq __user *)arg);
422 
423 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
424 		return -EFAULT;
425 
426 	ifr.ifr_name[IFNAMSIZ-1] = 0;
427 
428 	colon = strchr(ifr.ifr_name, ':');
429 	if (colon)
430 		*colon = 0;
431 
432 	/*
433 	 *	See which interface the caller is talking about.
434 	 */
435 
436 	switch (cmd) {
437 	/*
438 	 *	These ioctl calls:
439 	 *	- can be done by all.
440 	 *	- atomic and do not require locking.
441 	 *	- return a value
442 	 */
443 	case SIOCGIFFLAGS:
444 	case SIOCGIFMETRIC:
445 	case SIOCGIFMTU:
446 	case SIOCGIFHWADDR:
447 	case SIOCGIFSLAVE:
448 	case SIOCGIFMAP:
449 	case SIOCGIFINDEX:
450 	case SIOCGIFTXQLEN:
451 		dev_load(net, ifr.ifr_name);
452 		rcu_read_lock();
453 		ret = dev_ifsioc_locked(net, &ifr, cmd);
454 		rcu_read_unlock();
455 		if (!ret) {
456 			if (colon)
457 				*colon = ':';
458 			if (copy_to_user(arg, &ifr,
459 					 sizeof(struct ifreq)))
460 				ret = -EFAULT;
461 		}
462 		return ret;
463 
464 	case SIOCETHTOOL:
465 		dev_load(net, ifr.ifr_name);
466 		rtnl_lock();
467 		ret = dev_ethtool(net, &ifr);
468 		rtnl_unlock();
469 		if (!ret) {
470 			if (colon)
471 				*colon = ':';
472 			if (copy_to_user(arg, &ifr,
473 					 sizeof(struct ifreq)))
474 				ret = -EFAULT;
475 		}
476 		return ret;
477 
478 	/*
479 	 *	These ioctl calls:
480 	 *	- require superuser power.
481 	 *	- require strict serialization.
482 	 *	- return a value
483 	 */
484 	case SIOCGMIIPHY:
485 	case SIOCGMIIREG:
486 	case SIOCSIFNAME:
487 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
488 			return -EPERM;
489 		dev_load(net, ifr.ifr_name);
490 		rtnl_lock();
491 		ret = dev_ifsioc(net, &ifr, cmd);
492 		rtnl_unlock();
493 		if (!ret) {
494 			if (colon)
495 				*colon = ':';
496 			if (copy_to_user(arg, &ifr,
497 					 sizeof(struct ifreq)))
498 				ret = -EFAULT;
499 		}
500 		return ret;
501 
502 	/*
503 	 *	These ioctl calls:
504 	 *	- require superuser power.
505 	 *	- require strict serialization.
506 	 *	- do not return a value
507 	 */
508 	case SIOCSIFMAP:
509 	case SIOCSIFTXQLEN:
510 		if (!capable(CAP_NET_ADMIN))
511 			return -EPERM;
512 		/* fall through */
513 	/*
514 	 *	These ioctl calls:
515 	 *	- require local superuser power.
516 	 *	- require strict serialization.
517 	 *	- do not return a value
518 	 */
519 	case SIOCSIFFLAGS:
520 	case SIOCSIFMETRIC:
521 	case SIOCSIFMTU:
522 	case SIOCSIFHWADDR:
523 	case SIOCSIFSLAVE:
524 	case SIOCADDMULTI:
525 	case SIOCDELMULTI:
526 	case SIOCSIFHWBROADCAST:
527 	case SIOCSMIIREG:
528 	case SIOCBONDENSLAVE:
529 	case SIOCBONDRELEASE:
530 	case SIOCBONDSETHWADDR:
531 	case SIOCBONDCHANGEACTIVE:
532 	case SIOCBRADDIF:
533 	case SIOCBRDELIF:
534 	case SIOCSHWTSTAMP:
535 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
536 			return -EPERM;
537 		/* fall through */
538 	case SIOCBONDSLAVEINFOQUERY:
539 	case SIOCBONDINFOQUERY:
540 		dev_load(net, ifr.ifr_name);
541 		rtnl_lock();
542 		ret = dev_ifsioc(net, &ifr, cmd);
543 		rtnl_unlock();
544 		return ret;
545 
546 	case SIOCGIFMEM:
547 		/* Get the per device memory space. We can add this but
548 		 * currently do not support it */
549 	case SIOCSIFMEM:
550 		/* Set the per device memory buffer space.
551 		 * Not applicable in our case */
552 	case SIOCSIFLINK:
553 		return -ENOTTY;
554 
555 	/*
556 	 *	Unknown or private ioctl.
557 	 */
558 	default:
559 		if (cmd == SIOCWANDEV ||
560 		    (cmd >= SIOCDEVPRIVATE &&
561 		     cmd <= SIOCDEVPRIVATE + 15)) {
562 			dev_load(net, ifr.ifr_name);
563 			rtnl_lock();
564 			ret = dev_ifsioc(net, &ifr, cmd);
565 			rtnl_unlock();
566 			if (!ret && copy_to_user(arg, &ifr,
567 						 sizeof(struct ifreq)))
568 				ret = -EFAULT;
569 			return ret;
570 		}
571 		/* Take care of Wireless Extensions */
572 		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
573 			return wext_handle_ioctl(net, &ifr, cmd, arg);
574 		return -ENOTTY;
575 	}
576 }
577