xref: /openbmc/linux/net/core/dev_ioctl.c (revision 84fbfc33)
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 	ifr.ifr_name[IFNAMSIZ-1] = 0;
32 
33 	error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
34 	if (error)
35 		return error;
36 
37 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
38 		return -EFAULT;
39 	return 0;
40 }
41 
42 static gifconf_func_t *gifconf_list[NPROTO];
43 
44 /**
45  *	register_gifconf	-	register a SIOCGIF handler
46  *	@family: Address family
47  *	@gifconf: Function handler
48  *
49  *	Register protocol dependent address dumping routines. The handler
50  *	that is passed must not be freed or reused until it has been replaced
51  *	by another handler.
52  */
53 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
54 {
55 	if (family >= NPROTO)
56 		return -EINVAL;
57 	gifconf_list[family] = gifconf;
58 	return 0;
59 }
60 EXPORT_SYMBOL(register_gifconf);
61 
62 /*
63  *	Perform a SIOCGIFCONF call. This structure will change
64  *	size eventually, and there is nothing I can do about it.
65  *	Thus we will need a 'compatibility mode'.
66  */
67 
68 static int dev_ifconf(struct net *net, char __user *arg)
69 {
70 	struct ifconf ifc;
71 	struct net_device *dev;
72 	char __user *pos;
73 	int len;
74 	int total;
75 	int i;
76 
77 	/*
78 	 *	Fetch the caller's info block.
79 	 */
80 
81 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
82 		return -EFAULT;
83 
84 	pos = ifc.ifc_buf;
85 	len = ifc.ifc_len;
86 
87 	/*
88 	 *	Loop over the interfaces, and write an info block for each.
89 	 */
90 
91 	total = 0;
92 	for_each_netdev(net, dev) {
93 		for (i = 0; i < NPROTO; i++) {
94 			if (gifconf_list[i]) {
95 				int done;
96 				if (!pos)
97 					done = gifconf_list[i](dev, NULL, 0);
98 				else
99 					done = gifconf_list[i](dev, pos + total,
100 							       len - total);
101 				if (done < 0)
102 					return -EFAULT;
103 				total += done;
104 			}
105 		}
106 	}
107 
108 	/*
109 	 *	All done.  Write the updated control block back to the caller.
110 	 */
111 	ifc.ifc_len = total;
112 
113 	/*
114 	 * 	Both BSD and Solaris return 0 here, so we do too.
115 	 */
116 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
117 }
118 
119 /*
120  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
121  */
122 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
123 {
124 	int err;
125 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
126 
127 	if (!dev)
128 		return -ENODEV;
129 
130 	switch (cmd) {
131 	case SIOCGIFFLAGS:	/* Get interface flags */
132 		ifr->ifr_flags = (short) dev_get_flags(dev);
133 		return 0;
134 
135 	case SIOCGIFMETRIC:	/* Get the metric on the interface
136 				   (currently unused) */
137 		ifr->ifr_metric = 0;
138 		return 0;
139 
140 	case SIOCGIFMTU:	/* Get the MTU of a device */
141 		ifr->ifr_mtu = dev->mtu;
142 		return 0;
143 
144 	case SIOCGIFHWADDR:
145 		if (!dev->addr_len)
146 			memset(ifr->ifr_hwaddr.sa_data, 0,
147 			       sizeof(ifr->ifr_hwaddr.sa_data));
148 		else
149 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
150 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
151 				   (size_t)dev->addr_len));
152 		ifr->ifr_hwaddr.sa_family = dev->type;
153 		return 0;
154 
155 	case SIOCGIFSLAVE:
156 		err = -EINVAL;
157 		break;
158 
159 	case SIOCGIFMAP:
160 		ifr->ifr_map.mem_start = dev->mem_start;
161 		ifr->ifr_map.mem_end   = dev->mem_end;
162 		ifr->ifr_map.base_addr = dev->base_addr;
163 		ifr->ifr_map.irq       = dev->irq;
164 		ifr->ifr_map.dma       = dev->dma;
165 		ifr->ifr_map.port      = dev->if_port;
166 		return 0;
167 
168 	case SIOCGIFINDEX:
169 		ifr->ifr_ifindex = dev->ifindex;
170 		return 0;
171 
172 	case SIOCGIFTXQLEN:
173 		ifr->ifr_qlen = dev->tx_queue_len;
174 		return 0;
175 
176 	default:
177 		/* dev_ioctl() should ensure this case
178 		 * is never reached
179 		 */
180 		WARN_ON(1);
181 		err = -ENOTTY;
182 		break;
183 
184 	}
185 	return err;
186 }
187 
188 static int net_hwtstamp_validate(struct ifreq *ifr)
189 {
190 	struct hwtstamp_config cfg;
191 	enum hwtstamp_tx_types tx_type;
192 	enum hwtstamp_rx_filters rx_filter;
193 	int tx_type_valid = 0;
194 	int rx_filter_valid = 0;
195 
196 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
197 		return -EFAULT;
198 
199 	if (cfg.flags) /* reserved for future extensions */
200 		return -EINVAL;
201 
202 	tx_type = cfg.tx_type;
203 	rx_filter = cfg.rx_filter;
204 
205 	switch (tx_type) {
206 	case HWTSTAMP_TX_OFF:
207 	case HWTSTAMP_TX_ON:
208 	case HWTSTAMP_TX_ONESTEP_SYNC:
209 		tx_type_valid = 1;
210 		break;
211 	}
212 
213 	switch (rx_filter) {
214 	case HWTSTAMP_FILTER_NONE:
215 	case HWTSTAMP_FILTER_ALL:
216 	case HWTSTAMP_FILTER_SOME:
217 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
219 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
220 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
222 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
223 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
225 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
226 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
227 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
228 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
229 	case HWTSTAMP_FILTER_NTP_ALL:
230 		rx_filter_valid = 1;
231 		break;
232 	}
233 
234 	if (!tx_type_valid || !rx_filter_valid)
235 		return -ERANGE;
236 
237 	return 0;
238 }
239 
240 /*
241  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
242  */
243 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
244 {
245 	int err;
246 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
247 	const struct net_device_ops *ops;
248 
249 	if (!dev)
250 		return -ENODEV;
251 
252 	ops = dev->netdev_ops;
253 
254 	switch (cmd) {
255 	case SIOCSIFFLAGS:	/* Set interface flags */
256 		return dev_change_flags(dev, ifr->ifr_flags);
257 
258 	case SIOCSIFMETRIC:	/* Set the metric on the interface
259 				   (currently unused) */
260 		return -EOPNOTSUPP;
261 
262 	case SIOCSIFMTU:	/* Set the MTU of a device */
263 		return dev_set_mtu(dev, ifr->ifr_mtu);
264 
265 	case SIOCSIFHWADDR:
266 		if (dev->addr_len > sizeof(struct sockaddr))
267 			return -EINVAL;
268 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
269 
270 	case SIOCSIFHWBROADCAST:
271 		if (ifr->ifr_hwaddr.sa_family != dev->type)
272 			return -EINVAL;
273 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
274 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
275 			   (size_t)dev->addr_len));
276 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
277 		return 0;
278 
279 	case SIOCSIFMAP:
280 		if (ops->ndo_set_config) {
281 			if (!netif_device_present(dev))
282 				return -ENODEV;
283 			return ops->ndo_set_config(dev, &ifr->ifr_map);
284 		}
285 		return -EOPNOTSUPP;
286 
287 	case SIOCADDMULTI:
288 		if (!ops->ndo_set_rx_mode ||
289 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
290 			return -EINVAL;
291 		if (!netif_device_present(dev))
292 			return -ENODEV;
293 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
294 
295 	case SIOCDELMULTI:
296 		if (!ops->ndo_set_rx_mode ||
297 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
298 			return -EINVAL;
299 		if (!netif_device_present(dev))
300 			return -ENODEV;
301 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
302 
303 	case SIOCSIFTXQLEN:
304 		if (ifr->ifr_qlen < 0)
305 			return -EINVAL;
306 		dev->tx_queue_len = ifr->ifr_qlen;
307 		return 0;
308 
309 	case SIOCSIFNAME:
310 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
311 		return dev_change_name(dev, ifr->ifr_newname);
312 
313 	case SIOCSHWTSTAMP:
314 		err = net_hwtstamp_validate(ifr);
315 		if (err)
316 			return err;
317 		/* fall through */
318 
319 	/*
320 	 *	Unknown or private ioctl
321 	 */
322 	default:
323 		if ((cmd >= SIOCDEVPRIVATE &&
324 		    cmd <= SIOCDEVPRIVATE + 15) ||
325 		    cmd == SIOCBONDENSLAVE ||
326 		    cmd == SIOCBONDRELEASE ||
327 		    cmd == SIOCBONDSETHWADDR ||
328 		    cmd == SIOCBONDSLAVEINFOQUERY ||
329 		    cmd == SIOCBONDINFOQUERY ||
330 		    cmd == SIOCBONDCHANGEACTIVE ||
331 		    cmd == SIOCGMIIPHY ||
332 		    cmd == SIOCGMIIREG ||
333 		    cmd == SIOCSMIIREG ||
334 		    cmd == SIOCBRADDIF ||
335 		    cmd == SIOCBRDELIF ||
336 		    cmd == SIOCSHWTSTAMP ||
337 		    cmd == SIOCGHWTSTAMP ||
338 		    cmd == SIOCWANDEV) {
339 			err = -EOPNOTSUPP;
340 			if (ops->ndo_do_ioctl) {
341 				if (netif_device_present(dev))
342 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
343 				else
344 					err = -ENODEV;
345 			}
346 		} else
347 			err = -EINVAL;
348 
349 	}
350 	return err;
351 }
352 
353 /**
354  *	dev_load 	- load a network module
355  *	@net: the applicable net namespace
356  *	@name: name of interface
357  *
358  *	If a network interface is not present and the process has suitable
359  *	privileges this function loads the module. If module loading is not
360  *	available in this kernel then it becomes a nop.
361  */
362 
363 void dev_load(struct net *net, const char *name)
364 {
365 	struct net_device *dev;
366 	int no_module;
367 
368 	rcu_read_lock();
369 	dev = dev_get_by_name_rcu(net, name);
370 	rcu_read_unlock();
371 
372 	no_module = !dev;
373 	if (no_module && capable(CAP_NET_ADMIN))
374 		no_module = request_module("netdev-%s", name);
375 	if (no_module && capable(CAP_SYS_MODULE))
376 		request_module("%s", name);
377 }
378 EXPORT_SYMBOL(dev_load);
379 
380 /*
381  *	This function handles all "interface"-type I/O control requests. The actual
382  *	'doing' part of this is dev_ifsioc above.
383  */
384 
385 /**
386  *	dev_ioctl	-	network device ioctl
387  *	@net: the applicable net namespace
388  *	@cmd: command to issue
389  *	@arg: pointer to a struct ifreq in user space
390  *
391  *	Issue ioctl functions to devices. This is normally called by the
392  *	user space syscall interfaces but can sometimes be useful for
393  *	other purposes. The return value is the return from the syscall if
394  *	positive or a negative errno code on error.
395  */
396 
397 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
398 {
399 	struct ifreq ifr;
400 	int ret;
401 	char *colon;
402 
403 	/* One special case: SIOCGIFCONF takes ifconf argument
404 	   and requires shared lock, because it sleeps writing
405 	   to user space.
406 	 */
407 
408 	if (cmd == SIOCGIFCONF) {
409 		rtnl_lock();
410 		ret = dev_ifconf(net, (char __user *) arg);
411 		rtnl_unlock();
412 		return ret;
413 	}
414 	if (cmd == SIOCGIFNAME)
415 		return dev_ifname(net, (struct ifreq __user *)arg);
416 
417 	/*
418 	 * Take care of Wireless Extensions. Unfortunately struct iwreq
419 	 * isn't a proper subset of struct ifreq (it's 8 byte shorter)
420 	 * so we need to treat it specially, otherwise applications may
421 	 * fault if the struct they're passing happens to land at the
422 	 * end of a mapped page.
423 	 */
424 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
425 		struct iwreq iwr;
426 
427 		if (copy_from_user(&iwr, arg, sizeof(iwr)))
428 			return -EFAULT;
429 
430 		iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
431 
432 		return wext_handle_ioctl(net, &iwr, cmd, arg);
433 	}
434 
435 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
436 		return -EFAULT;
437 
438 	ifr.ifr_name[IFNAMSIZ-1] = 0;
439 
440 	colon = strchr(ifr.ifr_name, ':');
441 	if (colon)
442 		*colon = 0;
443 
444 	/*
445 	 *	See which interface the caller is talking about.
446 	 */
447 
448 	switch (cmd) {
449 	/*
450 	 *	These ioctl calls:
451 	 *	- can be done by all.
452 	 *	- atomic and do not require locking.
453 	 *	- return a value
454 	 */
455 	case SIOCGIFFLAGS:
456 	case SIOCGIFMETRIC:
457 	case SIOCGIFMTU:
458 	case SIOCGIFHWADDR:
459 	case SIOCGIFSLAVE:
460 	case SIOCGIFMAP:
461 	case SIOCGIFINDEX:
462 	case SIOCGIFTXQLEN:
463 		dev_load(net, ifr.ifr_name);
464 		rcu_read_lock();
465 		ret = dev_ifsioc_locked(net, &ifr, cmd);
466 		rcu_read_unlock();
467 		if (!ret) {
468 			if (colon)
469 				*colon = ':';
470 			if (copy_to_user(arg, &ifr,
471 					 sizeof(struct ifreq)))
472 				ret = -EFAULT;
473 		}
474 		return ret;
475 
476 	case SIOCETHTOOL:
477 		dev_load(net, ifr.ifr_name);
478 		rtnl_lock();
479 		ret = dev_ethtool(net, &ifr);
480 		rtnl_unlock();
481 		if (!ret) {
482 			if (colon)
483 				*colon = ':';
484 			if (copy_to_user(arg, &ifr,
485 					 sizeof(struct ifreq)))
486 				ret = -EFAULT;
487 		}
488 		return ret;
489 
490 	/*
491 	 *	These ioctl calls:
492 	 *	- require superuser power.
493 	 *	- require strict serialization.
494 	 *	- return a value
495 	 */
496 	case SIOCGMIIPHY:
497 	case SIOCGMIIREG:
498 	case SIOCSIFNAME:
499 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
500 			return -EPERM;
501 		dev_load(net, ifr.ifr_name);
502 		rtnl_lock();
503 		ret = dev_ifsioc(net, &ifr, cmd);
504 		rtnl_unlock();
505 		if (!ret) {
506 			if (colon)
507 				*colon = ':';
508 			if (copy_to_user(arg, &ifr,
509 					 sizeof(struct ifreq)))
510 				ret = -EFAULT;
511 		}
512 		return ret;
513 
514 	/*
515 	 *	These ioctl calls:
516 	 *	- require superuser power.
517 	 *	- require strict serialization.
518 	 *	- do not return a value
519 	 */
520 	case SIOCSIFMAP:
521 	case SIOCSIFTXQLEN:
522 		if (!capable(CAP_NET_ADMIN))
523 			return -EPERM;
524 		/* fall through */
525 	/*
526 	 *	These ioctl calls:
527 	 *	- require local superuser power.
528 	 *	- require strict serialization.
529 	 *	- do not return a value
530 	 */
531 	case SIOCSIFFLAGS:
532 	case SIOCSIFMETRIC:
533 	case SIOCSIFMTU:
534 	case SIOCSIFHWADDR:
535 	case SIOCSIFSLAVE:
536 	case SIOCADDMULTI:
537 	case SIOCDELMULTI:
538 	case SIOCSIFHWBROADCAST:
539 	case SIOCSMIIREG:
540 	case SIOCBONDENSLAVE:
541 	case SIOCBONDRELEASE:
542 	case SIOCBONDSETHWADDR:
543 	case SIOCBONDCHANGEACTIVE:
544 	case SIOCBRADDIF:
545 	case SIOCBRDELIF:
546 	case SIOCSHWTSTAMP:
547 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
548 			return -EPERM;
549 		/* fall through */
550 	case SIOCBONDSLAVEINFOQUERY:
551 	case SIOCBONDINFOQUERY:
552 		dev_load(net, ifr.ifr_name);
553 		rtnl_lock();
554 		ret = dev_ifsioc(net, &ifr, cmd);
555 		rtnl_unlock();
556 		return ret;
557 
558 	case SIOCGIFMEM:
559 		/* Get the per device memory space. We can add this but
560 		 * currently do not support it */
561 	case SIOCSIFMEM:
562 		/* Set the per device memory buffer space.
563 		 * Not applicable in our case */
564 	case SIOCSIFLINK:
565 		return -ENOTTY;
566 
567 	/*
568 	 *	Unknown or private ioctl.
569 	 */
570 	default:
571 		if (cmd == SIOCWANDEV ||
572 		    cmd == SIOCGHWTSTAMP ||
573 		    (cmd >= SIOCDEVPRIVATE &&
574 		     cmd <= SIOCDEVPRIVATE + 15)) {
575 			dev_load(net, ifr.ifr_name);
576 			rtnl_lock();
577 			ret = dev_ifsioc(net, &ifr, cmd);
578 			rtnl_unlock();
579 			if (!ret && copy_to_user(arg, &ifr,
580 						 sizeof(struct ifreq)))
581 				ret = -EFAULT;
582 			return ret;
583 		}
584 		return -ENOTTY;
585 	}
586 }
587