xref: /linux/net/core/dev_ioctl.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
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/dsa.h>
9 #include <net/wext.h>
10 
11 /*
12  *	Map an interface index to its name (SIOCGIFNAME)
13  */
14 
15 /*
16  *	We need this ioctl for efficient implementation of the
17  *	if_indextoname() function required by the IPv6 API.  Without
18  *	it, we would have to search all the interfaces to find a
19  *	match.  --pb
20  */
21 
22 static int dev_ifname(struct net *net, struct ifreq *ifr)
23 {
24 	ifr->ifr_name[IFNAMSIZ-1] = 0;
25 	return netdev_get_name(net, ifr->ifr_name, ifr->ifr_ifindex);
26 }
27 
28 static gifconf_func_t *gifconf_list[NPROTO];
29 
30 /**
31  *	register_gifconf	-	register a SIOCGIF handler
32  *	@family: Address family
33  *	@gifconf: Function handler
34  *
35  *	Register protocol dependent address dumping routines. The handler
36  *	that is passed must not be freed or reused until it has been replaced
37  *	by another handler.
38  */
39 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
40 {
41 	if (family >= NPROTO)
42 		return -EINVAL;
43 	gifconf_list[family] = gifconf;
44 	return 0;
45 }
46 EXPORT_SYMBOL(register_gifconf);
47 
48 /*
49  *	Perform a SIOCGIFCONF call. This structure will change
50  *	size eventually, and there is nothing I can do about it.
51  *	Thus we will need a 'compatibility mode'.
52  */
53 
54 int dev_ifconf(struct net *net, struct ifconf *ifc, int size)
55 {
56 	struct net_device *dev;
57 	char __user *pos;
58 	int len;
59 	int total;
60 	int i;
61 
62 	/*
63 	 *	Fetch the caller's info block.
64 	 */
65 
66 	pos = ifc->ifc_buf;
67 	len = ifc->ifc_len;
68 
69 	/*
70 	 *	Loop over the interfaces, and write an info block for each.
71 	 */
72 
73 	total = 0;
74 	for_each_netdev(net, dev) {
75 		for (i = 0; i < NPROTO; i++) {
76 			if (gifconf_list[i]) {
77 				int done;
78 				if (!pos)
79 					done = gifconf_list[i](dev, NULL, 0, size);
80 				else
81 					done = gifconf_list[i](dev, pos + total,
82 							       len - total, size);
83 				if (done < 0)
84 					return -EFAULT;
85 				total += done;
86 			}
87 		}
88 	}
89 
90 	/*
91 	 *	All done.  Write the updated control block back to the caller.
92 	 */
93 	ifc->ifc_len = total;
94 
95 	/*
96 	 * 	Both BSD and Solaris return 0 here, so we do too.
97 	 */
98 	return 0;
99 }
100 
101 /*
102  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
103  */
104 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
105 {
106 	int err;
107 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
108 
109 	if (!dev)
110 		return -ENODEV;
111 
112 	switch (cmd) {
113 	case SIOCGIFFLAGS:	/* Get interface flags */
114 		ifr->ifr_flags = (short) dev_get_flags(dev);
115 		return 0;
116 
117 	case SIOCGIFMETRIC:	/* Get the metric on the interface
118 				   (currently unused) */
119 		ifr->ifr_metric = 0;
120 		return 0;
121 
122 	case SIOCGIFMTU:	/* Get the MTU of a device */
123 		ifr->ifr_mtu = dev->mtu;
124 		return 0;
125 
126 	case SIOCGIFSLAVE:
127 		err = -EINVAL;
128 		break;
129 
130 	case SIOCGIFMAP:
131 		ifr->ifr_map.mem_start = dev->mem_start;
132 		ifr->ifr_map.mem_end   = dev->mem_end;
133 		ifr->ifr_map.base_addr = dev->base_addr;
134 		ifr->ifr_map.irq       = dev->irq;
135 		ifr->ifr_map.dma       = dev->dma;
136 		ifr->ifr_map.port      = dev->if_port;
137 		return 0;
138 
139 	case SIOCGIFINDEX:
140 		ifr->ifr_ifindex = dev->ifindex;
141 		return 0;
142 
143 	case SIOCGIFTXQLEN:
144 		ifr->ifr_qlen = dev->tx_queue_len;
145 		return 0;
146 
147 	default:
148 		/* dev_ioctl() should ensure this case
149 		 * is never reached
150 		 */
151 		WARN_ON(1);
152 		err = -ENOTTY;
153 		break;
154 
155 	}
156 	return err;
157 }
158 
159 static int net_hwtstamp_validate(struct ifreq *ifr)
160 {
161 	struct hwtstamp_config cfg;
162 	enum hwtstamp_tx_types tx_type;
163 	enum hwtstamp_rx_filters rx_filter;
164 	int tx_type_valid = 0;
165 	int rx_filter_valid = 0;
166 
167 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
168 		return -EFAULT;
169 
170 	if (cfg.flags) /* reserved for future extensions */
171 		return -EINVAL;
172 
173 	tx_type = cfg.tx_type;
174 	rx_filter = cfg.rx_filter;
175 
176 	switch (tx_type) {
177 	case HWTSTAMP_TX_OFF:
178 	case HWTSTAMP_TX_ON:
179 	case HWTSTAMP_TX_ONESTEP_SYNC:
180 	case HWTSTAMP_TX_ONESTEP_P2P:
181 		tx_type_valid = 1;
182 		break;
183 	case __HWTSTAMP_TX_CNT:
184 		/* not a real value */
185 		break;
186 	}
187 
188 	switch (rx_filter) {
189 	case HWTSTAMP_FILTER_NONE:
190 	case HWTSTAMP_FILTER_ALL:
191 	case HWTSTAMP_FILTER_SOME:
192 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
193 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
194 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
195 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
196 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
197 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
198 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
199 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
200 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
201 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
202 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
203 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
204 	case HWTSTAMP_FILTER_NTP_ALL:
205 		rx_filter_valid = 1;
206 		break;
207 	case __HWTSTAMP_FILTER_CNT:
208 		/* not a real value */
209 		break;
210 	}
211 
212 	if (!tx_type_valid || !rx_filter_valid)
213 		return -ERANGE;
214 
215 	return 0;
216 }
217 
218 static int dev_do_ioctl(struct net_device *dev,
219 			struct ifreq *ifr, unsigned int cmd)
220 {
221 	const struct net_device_ops *ops = dev->netdev_ops;
222 	int err;
223 
224 	err = dsa_ndo_do_ioctl(dev, ifr, cmd);
225 	if (err == 0 || err != -EOPNOTSUPP)
226 		return err;
227 
228 	if (ops->ndo_do_ioctl) {
229 		if (netif_device_present(dev))
230 			err = ops->ndo_do_ioctl(dev, ifr, cmd);
231 		else
232 			err = -ENODEV;
233 	}
234 
235 	return err;
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, NULL);
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 		if (dev->addr_len > sizeof(struct sockaddr))
265 			return -EINVAL;
266 		return dev_set_mac_address_user(dev, &ifr->ifr_hwaddr, NULL);
267 
268 	case SIOCSIFHWBROADCAST:
269 		if (ifr->ifr_hwaddr.sa_family != dev->type)
270 			return -EINVAL;
271 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
272 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
273 			   (size_t)dev->addr_len));
274 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
275 		return 0;
276 
277 	case SIOCSIFMAP:
278 		if (ops->ndo_set_config) {
279 			if (!netif_device_present(dev))
280 				return -ENODEV;
281 			return ops->ndo_set_config(dev, &ifr->ifr_map);
282 		}
283 		return -EOPNOTSUPP;
284 
285 	case SIOCADDMULTI:
286 		if (!ops->ndo_set_rx_mode ||
287 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
288 			return -EINVAL;
289 		if (!netif_device_present(dev))
290 			return -ENODEV;
291 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
292 
293 	case SIOCDELMULTI:
294 		if (!ops->ndo_set_rx_mode ||
295 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
296 			return -EINVAL;
297 		if (!netif_device_present(dev))
298 			return -ENODEV;
299 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
300 
301 	case SIOCSIFTXQLEN:
302 		if (ifr->ifr_qlen < 0)
303 			return -EINVAL;
304 		return dev_change_tx_queue_len(dev, ifr->ifr_qlen);
305 
306 	case SIOCSIFNAME:
307 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
308 		return dev_change_name(dev, ifr->ifr_newname);
309 
310 	case SIOCSHWTSTAMP:
311 		err = net_hwtstamp_validate(ifr);
312 		if (err)
313 			return err;
314 		fallthrough;
315 
316 	/*
317 	 *	Unknown or private ioctl
318 	 */
319 	default:
320 		if ((cmd >= SIOCDEVPRIVATE &&
321 		    cmd <= SIOCDEVPRIVATE + 15) ||
322 		    cmd == SIOCBONDENSLAVE ||
323 		    cmd == SIOCBONDRELEASE ||
324 		    cmd == SIOCBONDSETHWADDR ||
325 		    cmd == SIOCBONDSLAVEINFOQUERY ||
326 		    cmd == SIOCBONDINFOQUERY ||
327 		    cmd == SIOCBONDCHANGEACTIVE ||
328 		    cmd == SIOCGMIIPHY ||
329 		    cmd == SIOCGMIIREG ||
330 		    cmd == SIOCSMIIREG ||
331 		    cmd == SIOCBRADDIF ||
332 		    cmd == SIOCBRDELIF ||
333 		    cmd == SIOCSHWTSTAMP ||
334 		    cmd == SIOCGHWTSTAMP ||
335 		    cmd == SIOCWANDEV) {
336 			err = dev_do_ioctl(dev, ifr, cmd);
337 		} else
338 			err = -EINVAL;
339 
340 	}
341 	return err;
342 }
343 
344 /**
345  *	dev_load 	- load a network module
346  *	@net: the applicable net namespace
347  *	@name: name of interface
348  *
349  *	If a network interface is not present and the process has suitable
350  *	privileges this function loads the module. If module loading is not
351  *	available in this kernel then it becomes a nop.
352  */
353 
354 void dev_load(struct net *net, const char *name)
355 {
356 	struct net_device *dev;
357 	int no_module;
358 
359 	rcu_read_lock();
360 	dev = dev_get_by_name_rcu(net, name);
361 	rcu_read_unlock();
362 
363 	no_module = !dev;
364 	if (no_module && capable(CAP_NET_ADMIN))
365 		no_module = request_module("netdev-%s", name);
366 	if (no_module && capable(CAP_SYS_MODULE))
367 		request_module("%s", name);
368 }
369 EXPORT_SYMBOL(dev_load);
370 
371 /*
372  *	This function handles all "interface"-type I/O control requests. The actual
373  *	'doing' part of this is dev_ifsioc above.
374  */
375 
376 /**
377  *	dev_ioctl	-	network device ioctl
378  *	@net: the applicable net namespace
379  *	@cmd: command to issue
380  *	@ifr: pointer to a struct ifreq in user space
381  *	@need_copyout: whether or not copy_to_user() should be called
382  *
383  *	Issue ioctl functions to devices. This is normally called by the
384  *	user space syscall interfaces but can sometimes be useful for
385  *	other purposes. The return value is the return from the syscall if
386  *	positive or a negative errno code on error.
387  */
388 
389 int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_copyout)
390 {
391 	int ret;
392 	char *colon;
393 
394 	if (need_copyout)
395 		*need_copyout = true;
396 	if (cmd == SIOCGIFNAME)
397 		return dev_ifname(net, ifr);
398 
399 	ifr->ifr_name[IFNAMSIZ-1] = 0;
400 
401 	colon = strchr(ifr->ifr_name, ':');
402 	if (colon)
403 		*colon = 0;
404 
405 	/*
406 	 *	See which interface the caller is talking about.
407 	 */
408 
409 	switch (cmd) {
410 	case SIOCGIFHWADDR:
411 		dev_load(net, ifr->ifr_name);
412 		ret = dev_get_mac_address(&ifr->ifr_hwaddr, net, ifr->ifr_name);
413 		if (colon)
414 			*colon = ':';
415 		return ret;
416 	/*
417 	 *	These ioctl calls:
418 	 *	- can be done by all.
419 	 *	- atomic and do not require locking.
420 	 *	- return a value
421 	 */
422 	case SIOCGIFFLAGS:
423 	case SIOCGIFMETRIC:
424 	case SIOCGIFMTU:
425 	case SIOCGIFSLAVE:
426 	case SIOCGIFMAP:
427 	case SIOCGIFINDEX:
428 	case SIOCGIFTXQLEN:
429 		dev_load(net, ifr->ifr_name);
430 		rcu_read_lock();
431 		ret = dev_ifsioc_locked(net, ifr, cmd);
432 		rcu_read_unlock();
433 		if (colon)
434 			*colon = ':';
435 		return ret;
436 
437 	case SIOCETHTOOL:
438 		dev_load(net, ifr->ifr_name);
439 		rtnl_lock();
440 		ret = dev_ethtool(net, ifr);
441 		rtnl_unlock();
442 		if (colon)
443 			*colon = ':';
444 		return ret;
445 
446 	/*
447 	 *	These ioctl calls:
448 	 *	- require superuser power.
449 	 *	- require strict serialization.
450 	 *	- return a value
451 	 */
452 	case SIOCGMIIPHY:
453 	case SIOCGMIIREG:
454 	case SIOCSIFNAME:
455 		dev_load(net, ifr->ifr_name);
456 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
457 			return -EPERM;
458 		rtnl_lock();
459 		ret = dev_ifsioc(net, ifr, cmd);
460 		rtnl_unlock();
461 		if (colon)
462 			*colon = ':';
463 		return ret;
464 
465 	/*
466 	 *	These ioctl calls:
467 	 *	- require superuser power.
468 	 *	- require strict serialization.
469 	 *	- do not return a value
470 	 */
471 	case SIOCSIFMAP:
472 	case SIOCSIFTXQLEN:
473 		if (!capable(CAP_NET_ADMIN))
474 			return -EPERM;
475 		fallthrough;
476 	/*
477 	 *	These ioctl calls:
478 	 *	- require local superuser power.
479 	 *	- require strict serialization.
480 	 *	- do not return a value
481 	 */
482 	case SIOCSIFFLAGS:
483 	case SIOCSIFMETRIC:
484 	case SIOCSIFMTU:
485 	case SIOCSIFHWADDR:
486 	case SIOCSIFSLAVE:
487 	case SIOCADDMULTI:
488 	case SIOCDELMULTI:
489 	case SIOCSIFHWBROADCAST:
490 	case SIOCSMIIREG:
491 	case SIOCBONDENSLAVE:
492 	case SIOCBONDRELEASE:
493 	case SIOCBONDSETHWADDR:
494 	case SIOCBONDCHANGEACTIVE:
495 	case SIOCBRADDIF:
496 	case SIOCBRDELIF:
497 	case SIOCSHWTSTAMP:
498 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
499 			return -EPERM;
500 		fallthrough;
501 	case SIOCBONDSLAVEINFOQUERY:
502 	case SIOCBONDINFOQUERY:
503 		dev_load(net, ifr->ifr_name);
504 		rtnl_lock();
505 		ret = dev_ifsioc(net, ifr, cmd);
506 		rtnl_unlock();
507 		if (need_copyout)
508 			*need_copyout = false;
509 		return ret;
510 
511 	case SIOCGIFMEM:
512 		/* Get the per device memory space. We can add this but
513 		 * currently do not support it */
514 	case SIOCSIFMEM:
515 		/* Set the per device memory buffer space.
516 		 * Not applicable in our case */
517 	case SIOCSIFLINK:
518 		return -ENOTTY;
519 
520 	/*
521 	 *	Unknown or private ioctl.
522 	 */
523 	default:
524 		if (cmd == SIOCWANDEV ||
525 		    cmd == SIOCGHWTSTAMP ||
526 		    (cmd >= SIOCDEVPRIVATE &&
527 		     cmd <= SIOCDEVPRIVATE + 15)) {
528 			dev_load(net, ifr->ifr_name);
529 			rtnl_lock();
530 			ret = dev_ifsioc(net, ifr, cmd);
531 			rtnl_unlock();
532 			return ret;
533 		}
534 		return -ENOTTY;
535 	}
536 }
537