xref: /openbmc/linux/net/core/dev_ioctl.c (revision d3964221)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kmod.h>
3 #include <linux/netdevice.h>
4 #include <linux/etherdevice.h>
5 #include <linux/rtnetlink.h>
6 #include <linux/net_tstamp.h>
7 #include <linux/wireless.h>
8 #include <net/wext.h>
9 
10 /*
11  *	Map an interface index to its name (SIOCGIFNAME)
12  */
13 
14 /*
15  *	We need this ioctl for efficient implementation of the
16  *	if_indextoname() function required by the IPv6 API.  Without
17  *	it, we would have to search all the interfaces to find a
18  *	match.  --pb
19  */
20 
21 static int dev_ifname(struct net *net, struct ifreq __user *arg)
22 {
23 	struct ifreq ifr;
24 	int error;
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 	ifr.ifr_name[IFNAMSIZ-1] = 0;
33 
34 	error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
35 	if (error)
36 		return error;
37 
38 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
39 		return -EFAULT;
40 	return 0;
41 }
42 
43 static gifconf_func_t *gifconf_list[NPROTO];
44 
45 /**
46  *	register_gifconf	-	register a SIOCGIF handler
47  *	@family: Address family
48  *	@gifconf: Function handler
49  *
50  *	Register protocol dependent address dumping routines. The handler
51  *	that is passed must not be freed or reused until it has been replaced
52  *	by another handler.
53  */
54 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
55 {
56 	if (family >= NPROTO)
57 		return -EINVAL;
58 	gifconf_list[family] = gifconf;
59 	return 0;
60 }
61 EXPORT_SYMBOL(register_gifconf);
62 
63 /*
64  *	Perform a SIOCGIFCONF call. This structure will change
65  *	size eventually, and there is nothing I can do about it.
66  *	Thus we will need a 'compatibility mode'.
67  */
68 
69 static int dev_ifconf(struct net *net, char __user *arg)
70 {
71 	struct ifconf ifc;
72 	struct net_device *dev;
73 	char __user *pos;
74 	int len;
75 	int total;
76 	int i;
77 
78 	/*
79 	 *	Fetch the caller's info block.
80 	 */
81 
82 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
83 		return -EFAULT;
84 
85 	pos = ifc.ifc_buf;
86 	len = ifc.ifc_len;
87 
88 	/*
89 	 *	Loop over the interfaces, and write an info block for each.
90 	 */
91 
92 	total = 0;
93 	for_each_netdev(net, dev) {
94 		for (i = 0; i < NPROTO; i++) {
95 			if (gifconf_list[i]) {
96 				int done;
97 				if (!pos)
98 					done = gifconf_list[i](dev, NULL, 0);
99 				else
100 					done = gifconf_list[i](dev, pos + total,
101 							       len - total);
102 				if (done < 0)
103 					return -EFAULT;
104 				total += done;
105 			}
106 		}
107 	}
108 
109 	/*
110 	 *	All done.  Write the updated control block back to the caller.
111 	 */
112 	ifc.ifc_len = total;
113 
114 	/*
115 	 * 	Both BSD and Solaris return 0 here, so we do too.
116 	 */
117 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
118 }
119 
120 /*
121  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
122  */
123 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
124 {
125 	int err;
126 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
127 
128 	if (!dev)
129 		return -ENODEV;
130 
131 	switch (cmd) {
132 	case SIOCGIFFLAGS:	/* Get interface flags */
133 		ifr->ifr_flags = (short) dev_get_flags(dev);
134 		return 0;
135 
136 	case SIOCGIFMETRIC:	/* Get the metric on the interface
137 				   (currently unused) */
138 		ifr->ifr_metric = 0;
139 		return 0;
140 
141 	case SIOCGIFMTU:	/* Get the MTU of a device */
142 		ifr->ifr_mtu = dev->mtu;
143 		return 0;
144 
145 	case SIOCGIFHWADDR:
146 		if (!dev->addr_len)
147 			memset(ifr->ifr_hwaddr.sa_data, 0,
148 			       sizeof(ifr->ifr_hwaddr.sa_data));
149 		else
150 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
151 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
152 				   (size_t)dev->addr_len));
153 		ifr->ifr_hwaddr.sa_family = dev->type;
154 		return 0;
155 
156 	case SIOCGIFSLAVE:
157 		err = -EINVAL;
158 		break;
159 
160 	case SIOCGIFMAP:
161 		ifr->ifr_map.mem_start = dev->mem_start;
162 		ifr->ifr_map.mem_end   = dev->mem_end;
163 		ifr->ifr_map.base_addr = dev->base_addr;
164 		ifr->ifr_map.irq       = dev->irq;
165 		ifr->ifr_map.dma       = dev->dma;
166 		ifr->ifr_map.port      = dev->if_port;
167 		return 0;
168 
169 	case SIOCGIFINDEX:
170 		ifr->ifr_ifindex = dev->ifindex;
171 		return 0;
172 
173 	case SIOCGIFTXQLEN:
174 		ifr->ifr_qlen = dev->tx_queue_len;
175 		return 0;
176 
177 	default:
178 		/* dev_ioctl() should ensure this case
179 		 * is never reached
180 		 */
181 		WARN_ON(1);
182 		err = -ENOTTY;
183 		break;
184 
185 	}
186 	return err;
187 }
188 
189 static int net_hwtstamp_validate(struct ifreq *ifr)
190 {
191 	struct hwtstamp_config cfg;
192 	enum hwtstamp_tx_types tx_type;
193 	enum hwtstamp_rx_filters rx_filter;
194 	int tx_type_valid = 0;
195 	int rx_filter_valid = 0;
196 
197 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
198 		return -EFAULT;
199 
200 	if (cfg.flags) /* reserved for future extensions */
201 		return -EINVAL;
202 
203 	tx_type = cfg.tx_type;
204 	rx_filter = cfg.rx_filter;
205 
206 	switch (tx_type) {
207 	case HWTSTAMP_TX_OFF:
208 	case HWTSTAMP_TX_ON:
209 	case HWTSTAMP_TX_ONESTEP_SYNC:
210 		tx_type_valid = 1;
211 		break;
212 	}
213 
214 	switch (rx_filter) {
215 	case HWTSTAMP_FILTER_NONE:
216 	case HWTSTAMP_FILTER_ALL:
217 	case HWTSTAMP_FILTER_SOME:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
219 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
220 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
222 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
223 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
225 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
226 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
227 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
228 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
229 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
230 	case HWTSTAMP_FILTER_NTP_ALL:
231 		rx_filter_valid = 1;
232 		break;
233 	}
234 
235 	if (!tx_type_valid || !rx_filter_valid)
236 		return -ERANGE;
237 
238 	return 0;
239 }
240 
241 /*
242  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
243  */
244 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
245 {
246 	int err;
247 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
248 	const struct net_device_ops *ops;
249 
250 	if (!dev)
251 		return -ENODEV;
252 
253 	ops = dev->netdev_ops;
254 
255 	switch (cmd) {
256 	case SIOCSIFFLAGS:	/* Set interface flags */
257 		return dev_change_flags(dev, ifr->ifr_flags);
258 
259 	case SIOCSIFMETRIC:	/* Set the metric on the interface
260 				   (currently unused) */
261 		return -EOPNOTSUPP;
262 
263 	case SIOCSIFMTU:	/* Set the MTU of a device */
264 		return dev_set_mtu(dev, ifr->ifr_mtu);
265 
266 	case SIOCSIFHWADDR:
267 		if (dev->addr_len > sizeof(struct sockaddr))
268 			return -EINVAL;
269 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
270 
271 	case SIOCSIFHWBROADCAST:
272 		if (ifr->ifr_hwaddr.sa_family != dev->type)
273 			return -EINVAL;
274 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
275 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
276 			   (size_t)dev->addr_len));
277 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
278 		return 0;
279 
280 	case SIOCSIFMAP:
281 		if (ops->ndo_set_config) {
282 			if (!netif_device_present(dev))
283 				return -ENODEV;
284 			return ops->ndo_set_config(dev, &ifr->ifr_map);
285 		}
286 		return -EOPNOTSUPP;
287 
288 	case SIOCADDMULTI:
289 		if (!ops->ndo_set_rx_mode ||
290 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
291 			return -EINVAL;
292 		if (!netif_device_present(dev))
293 			return -ENODEV;
294 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
295 
296 	case SIOCDELMULTI:
297 		if (!ops->ndo_set_rx_mode ||
298 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
299 			return -EINVAL;
300 		if (!netif_device_present(dev))
301 			return -ENODEV;
302 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
303 
304 	case SIOCSIFTXQLEN:
305 		if (ifr->ifr_qlen < 0)
306 			return -EINVAL;
307 		if (dev->tx_queue_len ^ ifr->ifr_qlen) {
308 			unsigned int orig_len = dev->tx_queue_len;
309 
310 			dev->tx_queue_len = ifr->ifr_qlen;
311 			err = call_netdevice_notifiers(
312 					NETDEV_CHANGE_TX_QUEUE_LEN, dev);
313 			err = notifier_to_errno(err);
314 			if (err) {
315 				dev->tx_queue_len = orig_len;
316 				return err;
317 			}
318 		}
319 		return 0;
320 
321 	case SIOCSIFNAME:
322 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
323 		return dev_change_name(dev, ifr->ifr_newname);
324 
325 	case SIOCSHWTSTAMP:
326 		err = net_hwtstamp_validate(ifr);
327 		if (err)
328 			return err;
329 		/* fall through */
330 
331 	/*
332 	 *	Unknown or private ioctl
333 	 */
334 	default:
335 		if ((cmd >= SIOCDEVPRIVATE &&
336 		    cmd <= SIOCDEVPRIVATE + 15) ||
337 		    cmd == SIOCBONDENSLAVE ||
338 		    cmd == SIOCBONDRELEASE ||
339 		    cmd == SIOCBONDSETHWADDR ||
340 		    cmd == SIOCBONDSLAVEINFOQUERY ||
341 		    cmd == SIOCBONDINFOQUERY ||
342 		    cmd == SIOCBONDCHANGEACTIVE ||
343 		    cmd == SIOCGMIIPHY ||
344 		    cmd == SIOCGMIIREG ||
345 		    cmd == SIOCSMIIREG ||
346 		    cmd == SIOCBRADDIF ||
347 		    cmd == SIOCBRDELIF ||
348 		    cmd == SIOCSHWTSTAMP ||
349 		    cmd == SIOCGHWTSTAMP ||
350 		    cmd == SIOCWANDEV) {
351 			err = -EOPNOTSUPP;
352 			if (ops->ndo_do_ioctl) {
353 				if (netif_device_present(dev))
354 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
355 				else
356 					err = -ENODEV;
357 			}
358 		} else
359 			err = -EINVAL;
360 
361 	}
362 	return err;
363 }
364 
365 /**
366  *	dev_load 	- load a network module
367  *	@net: the applicable net namespace
368  *	@name: name of interface
369  *
370  *	If a network interface is not present and the process has suitable
371  *	privileges this function loads the module. If module loading is not
372  *	available in this kernel then it becomes a nop.
373  */
374 
375 void dev_load(struct net *net, const char *name)
376 {
377 	struct net_device *dev;
378 	int no_module;
379 
380 	rcu_read_lock();
381 	dev = dev_get_by_name_rcu(net, name);
382 	rcu_read_unlock();
383 
384 	no_module = !dev;
385 	if (no_module && capable(CAP_NET_ADMIN))
386 		no_module = request_module("netdev-%s", name);
387 	if (no_module && capable(CAP_SYS_MODULE))
388 		request_module("%s", name);
389 }
390 EXPORT_SYMBOL(dev_load);
391 
392 /*
393  *	This function handles all "interface"-type I/O control requests. The actual
394  *	'doing' part of this is dev_ifsioc above.
395  */
396 
397 /**
398  *	dev_ioctl	-	network device ioctl
399  *	@net: the applicable net namespace
400  *	@cmd: command to issue
401  *	@arg: pointer to a struct ifreq in user space
402  *
403  *	Issue ioctl functions to devices. This is normally called by the
404  *	user space syscall interfaces but can sometimes be useful for
405  *	other purposes. The return value is the return from the syscall if
406  *	positive or a negative errno code on error.
407  */
408 
409 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
410 {
411 	struct ifreq ifr;
412 	int ret;
413 	char *colon;
414 
415 	/* One special case: SIOCGIFCONF takes ifconf argument
416 	   and requires shared lock, because it sleeps writing
417 	   to user space.
418 	 */
419 
420 	if (cmd == SIOCGIFCONF) {
421 		rtnl_lock();
422 		ret = dev_ifconf(net, (char __user *) arg);
423 		rtnl_unlock();
424 		return ret;
425 	}
426 	if (cmd == SIOCGIFNAME)
427 		return dev_ifname(net, (struct ifreq __user *)arg);
428 
429 	/*
430 	 * Take care of Wireless Extensions. Unfortunately struct iwreq
431 	 * isn't a proper subset of struct ifreq (it's 8 byte shorter)
432 	 * so we need to treat it specially, otherwise applications may
433 	 * fault if the struct they're passing happens to land at the
434 	 * end of a mapped page.
435 	 */
436 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
437 		struct iwreq iwr;
438 
439 		if (copy_from_user(&iwr, arg, sizeof(iwr)))
440 			return -EFAULT;
441 
442 		iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
443 
444 		return wext_handle_ioctl(net, &iwr, cmd, arg);
445 	}
446 
447 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
448 		return -EFAULT;
449 
450 	ifr.ifr_name[IFNAMSIZ-1] = 0;
451 
452 	colon = strchr(ifr.ifr_name, ':');
453 	if (colon)
454 		*colon = 0;
455 
456 	/*
457 	 *	See which interface the caller is talking about.
458 	 */
459 
460 	switch (cmd) {
461 	/*
462 	 *	These ioctl calls:
463 	 *	- can be done by all.
464 	 *	- atomic and do not require locking.
465 	 *	- return a value
466 	 */
467 	case SIOCGIFFLAGS:
468 	case SIOCGIFMETRIC:
469 	case SIOCGIFMTU:
470 	case SIOCGIFHWADDR:
471 	case SIOCGIFSLAVE:
472 	case SIOCGIFMAP:
473 	case SIOCGIFINDEX:
474 	case SIOCGIFTXQLEN:
475 		dev_load(net, ifr.ifr_name);
476 		rcu_read_lock();
477 		ret = dev_ifsioc_locked(net, &ifr, cmd);
478 		rcu_read_unlock();
479 		if (!ret) {
480 			if (colon)
481 				*colon = ':';
482 			if (copy_to_user(arg, &ifr,
483 					 sizeof(struct ifreq)))
484 				ret = -EFAULT;
485 		}
486 		return ret;
487 
488 	case SIOCETHTOOL:
489 		dev_load(net, ifr.ifr_name);
490 		rtnl_lock();
491 		ret = dev_ethtool(net, &ifr);
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 	 *	- return a value
507 	 */
508 	case SIOCGMIIPHY:
509 	case SIOCGMIIREG:
510 	case SIOCSIFNAME:
511 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
512 			return -EPERM;
513 		dev_load(net, ifr.ifr_name);
514 		rtnl_lock();
515 		ret = dev_ifsioc(net, &ifr, cmd);
516 		rtnl_unlock();
517 		if (!ret) {
518 			if (colon)
519 				*colon = ':';
520 			if (copy_to_user(arg, &ifr,
521 					 sizeof(struct ifreq)))
522 				ret = -EFAULT;
523 		}
524 		return ret;
525 
526 	/*
527 	 *	These ioctl calls:
528 	 *	- require superuser power.
529 	 *	- require strict serialization.
530 	 *	- do not return a value
531 	 */
532 	case SIOCSIFMAP:
533 	case SIOCSIFTXQLEN:
534 		if (!capable(CAP_NET_ADMIN))
535 			return -EPERM;
536 		/* fall through */
537 	/*
538 	 *	These ioctl calls:
539 	 *	- require local superuser power.
540 	 *	- require strict serialization.
541 	 *	- do not return a value
542 	 */
543 	case SIOCSIFFLAGS:
544 	case SIOCSIFMETRIC:
545 	case SIOCSIFMTU:
546 	case SIOCSIFHWADDR:
547 	case SIOCSIFSLAVE:
548 	case SIOCADDMULTI:
549 	case SIOCDELMULTI:
550 	case SIOCSIFHWBROADCAST:
551 	case SIOCSMIIREG:
552 	case SIOCBONDENSLAVE:
553 	case SIOCBONDRELEASE:
554 	case SIOCBONDSETHWADDR:
555 	case SIOCBONDCHANGEACTIVE:
556 	case SIOCBRADDIF:
557 	case SIOCBRDELIF:
558 	case SIOCSHWTSTAMP:
559 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
560 			return -EPERM;
561 		/* fall through */
562 	case SIOCBONDSLAVEINFOQUERY:
563 	case SIOCBONDINFOQUERY:
564 		dev_load(net, ifr.ifr_name);
565 		rtnl_lock();
566 		ret = dev_ifsioc(net, &ifr, cmd);
567 		rtnl_unlock();
568 		return ret;
569 
570 	case SIOCGIFMEM:
571 		/* Get the per device memory space. We can add this but
572 		 * currently do not support it */
573 	case SIOCSIFMEM:
574 		/* Set the per device memory buffer space.
575 		 * Not applicable in our case */
576 	case SIOCSIFLINK:
577 		return -ENOTTY;
578 
579 	/*
580 	 *	Unknown or private ioctl.
581 	 */
582 	default:
583 		if (cmd == SIOCWANDEV ||
584 		    cmd == SIOCGHWTSTAMP ||
585 		    (cmd >= SIOCDEVPRIVATE &&
586 		     cmd <= SIOCDEVPRIVATE + 15)) {
587 			dev_load(net, ifr.ifr_name);
588 			rtnl_lock();
589 			ret = dev_ifsioc(net, &ifr, cmd);
590 			rtnl_unlock();
591 			if (!ret && copy_to_user(arg, &ifr,
592 						 sizeof(struct ifreq)))
593 				ret = -EFAULT;
594 			return ret;
595 		}
596 		return -ENOTTY;
597 	}
598 }
599