xref: /linux/net/core/dev_ioctl.c (revision af873fcecef567abf8a3468b06dd4e4aab46da6d)
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 *ifr)
22 {
23 	ifr->ifr_name[IFNAMSIZ-1] = 0;
24 	return netdev_get_name(net, ifr->ifr_name, ifr->ifr_ifindex);
25 }
26 
27 static gifconf_func_t *gifconf_list[NPROTO];
28 
29 /**
30  *	register_gifconf	-	register a SIOCGIF handler
31  *	@family: Address family
32  *	@gifconf: Function handler
33  *
34  *	Register protocol dependent address dumping routines. The handler
35  *	that is passed must not be freed or reused until it has been replaced
36  *	by another handler.
37  */
38 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
39 {
40 	if (family >= NPROTO)
41 		return -EINVAL;
42 	gifconf_list[family] = gifconf;
43 	return 0;
44 }
45 EXPORT_SYMBOL(register_gifconf);
46 
47 /*
48  *	Perform a SIOCGIFCONF call. This structure will change
49  *	size eventually, and there is nothing I can do about it.
50  *	Thus we will need a 'compatibility mode'.
51  */
52 
53 int dev_ifconf(struct net *net, struct ifconf *ifc, int size)
54 {
55 	struct net_device *dev;
56 	char __user *pos;
57 	int len;
58 	int total;
59 	int i;
60 
61 	/*
62 	 *	Fetch the caller's info block.
63 	 */
64 
65 	pos = ifc->ifc_buf;
66 	len = ifc->ifc_len;
67 
68 	/*
69 	 *	Loop over the interfaces, and write an info block for each.
70 	 */
71 
72 	total = 0;
73 	for_each_netdev(net, dev) {
74 		for (i = 0; i < NPROTO; i++) {
75 			if (gifconf_list[i]) {
76 				int done;
77 				if (!pos)
78 					done = gifconf_list[i](dev, NULL, 0, size);
79 				else
80 					done = gifconf_list[i](dev, pos + total,
81 							       len - total, size);
82 				if (done < 0)
83 					return -EFAULT;
84 				total += done;
85 			}
86 		}
87 	}
88 
89 	/*
90 	 *	All done.  Write the updated control block back to the caller.
91 	 */
92 	ifc->ifc_len = total;
93 
94 	/*
95 	 * 	Both BSD and Solaris return 0 here, so we do too.
96 	 */
97 	return 0;
98 }
99 
100 /*
101  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
102  */
103 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
104 {
105 	int err;
106 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
107 
108 	if (!dev)
109 		return -ENODEV;
110 
111 	switch (cmd) {
112 	case SIOCGIFFLAGS:	/* Get interface flags */
113 		ifr->ifr_flags = (short) dev_get_flags(dev);
114 		return 0;
115 
116 	case SIOCGIFMETRIC:	/* Get the metric on the interface
117 				   (currently unused) */
118 		ifr->ifr_metric = 0;
119 		return 0;
120 
121 	case SIOCGIFMTU:	/* Get the MTU of a device */
122 		ifr->ifr_mtu = dev->mtu;
123 		return 0;
124 
125 	case SIOCGIFHWADDR:
126 		if (!dev->addr_len)
127 			memset(ifr->ifr_hwaddr.sa_data, 0,
128 			       sizeof(ifr->ifr_hwaddr.sa_data));
129 		else
130 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
131 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
132 				   (size_t)dev->addr_len));
133 		ifr->ifr_hwaddr.sa_family = dev->type;
134 		return 0;
135 
136 	case SIOCGIFSLAVE:
137 		err = -EINVAL;
138 		break;
139 
140 	case SIOCGIFMAP:
141 		ifr->ifr_map.mem_start = dev->mem_start;
142 		ifr->ifr_map.mem_end   = dev->mem_end;
143 		ifr->ifr_map.base_addr = dev->base_addr;
144 		ifr->ifr_map.irq       = dev->irq;
145 		ifr->ifr_map.dma       = dev->dma;
146 		ifr->ifr_map.port      = dev->if_port;
147 		return 0;
148 
149 	case SIOCGIFINDEX:
150 		ifr->ifr_ifindex = dev->ifindex;
151 		return 0;
152 
153 	case SIOCGIFTXQLEN:
154 		ifr->ifr_qlen = dev->tx_queue_len;
155 		return 0;
156 
157 	default:
158 		/* dev_ioctl() should ensure this case
159 		 * is never reached
160 		 */
161 		WARN_ON(1);
162 		err = -ENOTTY;
163 		break;
164 
165 	}
166 	return err;
167 }
168 
169 static int net_hwtstamp_validate(struct ifreq *ifr)
170 {
171 	struct hwtstamp_config cfg;
172 	enum hwtstamp_tx_types tx_type;
173 	enum hwtstamp_rx_filters rx_filter;
174 	int tx_type_valid = 0;
175 	int rx_filter_valid = 0;
176 
177 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
178 		return -EFAULT;
179 
180 	if (cfg.flags) /* reserved for future extensions */
181 		return -EINVAL;
182 
183 	tx_type = cfg.tx_type;
184 	rx_filter = cfg.rx_filter;
185 
186 	switch (tx_type) {
187 	case HWTSTAMP_TX_OFF:
188 	case HWTSTAMP_TX_ON:
189 	case HWTSTAMP_TX_ONESTEP_SYNC:
190 		tx_type_valid = 1;
191 		break;
192 	}
193 
194 	switch (rx_filter) {
195 	case HWTSTAMP_FILTER_NONE:
196 	case HWTSTAMP_FILTER_ALL:
197 	case HWTSTAMP_FILTER_SOME:
198 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
199 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
200 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
201 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
202 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
203 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
204 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
205 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
206 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
207 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
208 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
209 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
210 	case HWTSTAMP_FILTER_NTP_ALL:
211 		rx_filter_valid = 1;
212 		break;
213 	}
214 
215 	if (!tx_type_valid || !rx_filter_valid)
216 		return -ERANGE;
217 
218 	return 0;
219 }
220 
221 /*
222  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
223  */
224 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
225 {
226 	int err;
227 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
228 	const struct net_device_ops *ops;
229 
230 	if (!dev)
231 		return -ENODEV;
232 
233 	ops = dev->netdev_ops;
234 
235 	switch (cmd) {
236 	case SIOCSIFFLAGS:	/* Set interface flags */
237 		return dev_change_flags(dev, ifr->ifr_flags, NULL);
238 
239 	case SIOCSIFMETRIC:	/* Set the metric on the interface
240 				   (currently unused) */
241 		return -EOPNOTSUPP;
242 
243 	case SIOCSIFMTU:	/* Set the MTU of a device */
244 		return dev_set_mtu(dev, ifr->ifr_mtu);
245 
246 	case SIOCSIFHWADDR:
247 		if (dev->addr_len > sizeof(struct sockaddr))
248 			return -EINVAL;
249 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr, NULL);
250 
251 	case SIOCSIFHWBROADCAST:
252 		if (ifr->ifr_hwaddr.sa_family != dev->type)
253 			return -EINVAL;
254 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
255 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
256 			   (size_t)dev->addr_len));
257 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
258 		return 0;
259 
260 	case SIOCSIFMAP:
261 		if (ops->ndo_set_config) {
262 			if (!netif_device_present(dev))
263 				return -ENODEV;
264 			return ops->ndo_set_config(dev, &ifr->ifr_map);
265 		}
266 		return -EOPNOTSUPP;
267 
268 	case SIOCADDMULTI:
269 		if (!ops->ndo_set_rx_mode ||
270 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
271 			return -EINVAL;
272 		if (!netif_device_present(dev))
273 			return -ENODEV;
274 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
275 
276 	case SIOCDELMULTI:
277 		if (!ops->ndo_set_rx_mode ||
278 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
279 			return -EINVAL;
280 		if (!netif_device_present(dev))
281 			return -ENODEV;
282 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
283 
284 	case SIOCSIFTXQLEN:
285 		if (ifr->ifr_qlen < 0)
286 			return -EINVAL;
287 		return dev_change_tx_queue_len(dev, ifr->ifr_qlen);
288 
289 	case SIOCSIFNAME:
290 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
291 		return dev_change_name(dev, ifr->ifr_newname);
292 
293 	case SIOCSHWTSTAMP:
294 		err = net_hwtstamp_validate(ifr);
295 		if (err)
296 			return err;
297 		/* fall through */
298 
299 	/*
300 	 *	Unknown or private ioctl
301 	 */
302 	default:
303 		if ((cmd >= SIOCDEVPRIVATE &&
304 		    cmd <= SIOCDEVPRIVATE + 15) ||
305 		    cmd == SIOCBONDENSLAVE ||
306 		    cmd == SIOCBONDRELEASE ||
307 		    cmd == SIOCBONDSETHWADDR ||
308 		    cmd == SIOCBONDSLAVEINFOQUERY ||
309 		    cmd == SIOCBONDINFOQUERY ||
310 		    cmd == SIOCBONDCHANGEACTIVE ||
311 		    cmd == SIOCGMIIPHY ||
312 		    cmd == SIOCGMIIREG ||
313 		    cmd == SIOCSMIIREG ||
314 		    cmd == SIOCBRADDIF ||
315 		    cmd == SIOCBRDELIF ||
316 		    cmd == SIOCSHWTSTAMP ||
317 		    cmd == SIOCGHWTSTAMP ||
318 		    cmd == SIOCWANDEV) {
319 			err = -EOPNOTSUPP;
320 			if (ops->ndo_do_ioctl) {
321 				if (netif_device_present(dev))
322 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
323 				else
324 					err = -ENODEV;
325 			}
326 		} else
327 			err = -EINVAL;
328 
329 	}
330 	return err;
331 }
332 
333 /**
334  *	dev_load 	- load a network module
335  *	@net: the applicable net namespace
336  *	@name: name of interface
337  *
338  *	If a network interface is not present and the process has suitable
339  *	privileges this function loads the module. If module loading is not
340  *	available in this kernel then it becomes a nop.
341  */
342 
343 void dev_load(struct net *net, const char *name)
344 {
345 	struct net_device *dev;
346 	int no_module;
347 
348 	rcu_read_lock();
349 	dev = dev_get_by_name_rcu(net, name);
350 	rcu_read_unlock();
351 
352 	no_module = !dev;
353 	if (no_module && capable(CAP_NET_ADMIN))
354 		no_module = request_module("netdev-%s", name);
355 	if (no_module && capable(CAP_SYS_MODULE))
356 		request_module("%s", name);
357 }
358 EXPORT_SYMBOL(dev_load);
359 
360 /*
361  *	This function handles all "interface"-type I/O control requests. The actual
362  *	'doing' part of this is dev_ifsioc above.
363  */
364 
365 /**
366  *	dev_ioctl	-	network device ioctl
367  *	@net: the applicable net namespace
368  *	@cmd: command to issue
369  *	@ifr: pointer to a struct ifreq in user space
370  *	@need_copyout: whether or not copy_to_user() should be called
371  *
372  *	Issue ioctl functions to devices. This is normally called by the
373  *	user space syscall interfaces but can sometimes be useful for
374  *	other purposes. The return value is the return from the syscall if
375  *	positive or a negative errno code on error.
376  */
377 
378 int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_copyout)
379 {
380 	int ret;
381 	char *colon;
382 
383 	if (need_copyout)
384 		*need_copyout = true;
385 	if (cmd == SIOCGIFNAME)
386 		return dev_ifname(net, ifr);
387 
388 	ifr->ifr_name[IFNAMSIZ-1] = 0;
389 
390 	colon = strchr(ifr->ifr_name, ':');
391 	if (colon)
392 		*colon = 0;
393 
394 	/*
395 	 *	See which interface the caller is talking about.
396 	 */
397 
398 	switch (cmd) {
399 	/*
400 	 *	These ioctl calls:
401 	 *	- can be done by all.
402 	 *	- atomic and do not require locking.
403 	 *	- return a value
404 	 */
405 	case SIOCGIFFLAGS:
406 	case SIOCGIFMETRIC:
407 	case SIOCGIFMTU:
408 	case SIOCGIFHWADDR:
409 	case SIOCGIFSLAVE:
410 	case SIOCGIFMAP:
411 	case SIOCGIFINDEX:
412 	case SIOCGIFTXQLEN:
413 		dev_load(net, ifr->ifr_name);
414 		rcu_read_lock();
415 		ret = dev_ifsioc_locked(net, ifr, cmd);
416 		rcu_read_unlock();
417 		if (colon)
418 			*colon = ':';
419 		return ret;
420 
421 	case SIOCETHTOOL:
422 		dev_load(net, ifr->ifr_name);
423 		rtnl_lock();
424 		ret = dev_ethtool(net, ifr);
425 		rtnl_unlock();
426 		if (colon)
427 			*colon = ':';
428 		return ret;
429 
430 	/*
431 	 *	These ioctl calls:
432 	 *	- require superuser power.
433 	 *	- require strict serialization.
434 	 *	- return a value
435 	 */
436 	case SIOCGMIIPHY:
437 	case SIOCGMIIREG:
438 	case SIOCSIFNAME:
439 		dev_load(net, ifr->ifr_name);
440 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
441 			return -EPERM;
442 		rtnl_lock();
443 		ret = dev_ifsioc(net, ifr, cmd);
444 		rtnl_unlock();
445 		if (colon)
446 			*colon = ':';
447 		return ret;
448 
449 	/*
450 	 *	These ioctl calls:
451 	 *	- require superuser power.
452 	 *	- require strict serialization.
453 	 *	- do not return a value
454 	 */
455 	case SIOCSIFMAP:
456 	case SIOCSIFTXQLEN:
457 		if (!capable(CAP_NET_ADMIN))
458 			return -EPERM;
459 		/* fall through */
460 	/*
461 	 *	These ioctl calls:
462 	 *	- require local superuser power.
463 	 *	- require strict serialization.
464 	 *	- do not return a value
465 	 */
466 	case SIOCSIFFLAGS:
467 	case SIOCSIFMETRIC:
468 	case SIOCSIFMTU:
469 	case SIOCSIFHWADDR:
470 	case SIOCSIFSLAVE:
471 	case SIOCADDMULTI:
472 	case SIOCDELMULTI:
473 	case SIOCSIFHWBROADCAST:
474 	case SIOCSMIIREG:
475 	case SIOCBONDENSLAVE:
476 	case SIOCBONDRELEASE:
477 	case SIOCBONDSETHWADDR:
478 	case SIOCBONDCHANGEACTIVE:
479 	case SIOCBRADDIF:
480 	case SIOCBRDELIF:
481 	case SIOCSHWTSTAMP:
482 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
483 			return -EPERM;
484 		/* fall through */
485 	case SIOCBONDSLAVEINFOQUERY:
486 	case SIOCBONDINFOQUERY:
487 		dev_load(net, ifr->ifr_name);
488 		rtnl_lock();
489 		ret = dev_ifsioc(net, ifr, cmd);
490 		rtnl_unlock();
491 		if (need_copyout)
492 			*need_copyout = false;
493 		return ret;
494 
495 	case SIOCGIFMEM:
496 		/* Get the per device memory space. We can add this but
497 		 * currently do not support it */
498 	case SIOCSIFMEM:
499 		/* Set the per device memory buffer space.
500 		 * Not applicable in our case */
501 	case SIOCSIFLINK:
502 		return -ENOTTY;
503 
504 	/*
505 	 *	Unknown or private ioctl.
506 	 */
507 	default:
508 		if (cmd == SIOCWANDEV ||
509 		    cmd == SIOCGHWTSTAMP ||
510 		    (cmd >= SIOCDEVPRIVATE &&
511 		     cmd <= SIOCDEVPRIVATE + 15)) {
512 			dev_load(net, ifr->ifr_name);
513 			rtnl_lock();
514 			ret = dev_ifsioc(net, ifr, cmd);
515 			rtnl_unlock();
516 			return ret;
517 		}
518 		return -ENOTTY;
519 	}
520 }
521