xref: /openbmc/linux/net/core/dev_ioctl.c (revision 4da722ca19f30f7db250db808d1ab1703607a932)
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 
32 	error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
33 	if (error)
34 		return error;
35 
36 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
37 		return -EFAULT;
38 	return 0;
39 }
40 
41 static gifconf_func_t *gifconf_list[NPROTO];
42 
43 /**
44  *	register_gifconf	-	register a SIOCGIF handler
45  *	@family: Address family
46  *	@gifconf: Function handler
47  *
48  *	Register protocol dependent address dumping routines. The handler
49  *	that is passed must not be freed or reused until it has been replaced
50  *	by another handler.
51  */
52 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
53 {
54 	if (family >= NPROTO)
55 		return -EINVAL;
56 	gifconf_list[family] = gifconf;
57 	return 0;
58 }
59 EXPORT_SYMBOL(register_gifconf);
60 
61 /*
62  *	Perform a SIOCGIFCONF call. This structure will change
63  *	size eventually, and there is nothing I can do about it.
64  *	Thus we will need a 'compatibility mode'.
65  */
66 
67 static int dev_ifconf(struct net *net, char __user *arg)
68 {
69 	struct ifconf ifc;
70 	struct net_device *dev;
71 	char __user *pos;
72 	int len;
73 	int total;
74 	int i;
75 
76 	/*
77 	 *	Fetch the caller's info block.
78 	 */
79 
80 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
81 		return -EFAULT;
82 
83 	pos = ifc.ifc_buf;
84 	len = ifc.ifc_len;
85 
86 	/*
87 	 *	Loop over the interfaces, and write an info block for each.
88 	 */
89 
90 	total = 0;
91 	for_each_netdev(net, dev) {
92 		for (i = 0; i < NPROTO; i++) {
93 			if (gifconf_list[i]) {
94 				int done;
95 				if (!pos)
96 					done = gifconf_list[i](dev, NULL, 0);
97 				else
98 					done = gifconf_list[i](dev, pos + total,
99 							       len - total);
100 				if (done < 0)
101 					return -EFAULT;
102 				total += done;
103 			}
104 		}
105 	}
106 
107 	/*
108 	 *	All done.  Write the updated control block back to the caller.
109 	 */
110 	ifc.ifc_len = total;
111 
112 	/*
113 	 * 	Both BSD and Solaris return 0 here, so we do too.
114 	 */
115 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
116 }
117 
118 /*
119  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
120  */
121 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
122 {
123 	int err;
124 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
125 
126 	if (!dev)
127 		return -ENODEV;
128 
129 	switch (cmd) {
130 	case SIOCGIFFLAGS:	/* Get interface flags */
131 		ifr->ifr_flags = (short) dev_get_flags(dev);
132 		return 0;
133 
134 	case SIOCGIFMETRIC:	/* Get the metric on the interface
135 				   (currently unused) */
136 		ifr->ifr_metric = 0;
137 		return 0;
138 
139 	case SIOCGIFMTU:	/* Get the MTU of a device */
140 		ifr->ifr_mtu = dev->mtu;
141 		return 0;
142 
143 	case SIOCGIFHWADDR:
144 		if (!dev->addr_len)
145 			memset(ifr->ifr_hwaddr.sa_data, 0,
146 			       sizeof(ifr->ifr_hwaddr.sa_data));
147 		else
148 			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
149 			       min(sizeof(ifr->ifr_hwaddr.sa_data),
150 				   (size_t)dev->addr_len));
151 		ifr->ifr_hwaddr.sa_family = dev->type;
152 		return 0;
153 
154 	case SIOCGIFSLAVE:
155 		err = -EINVAL;
156 		break;
157 
158 	case SIOCGIFMAP:
159 		ifr->ifr_map.mem_start = dev->mem_start;
160 		ifr->ifr_map.mem_end   = dev->mem_end;
161 		ifr->ifr_map.base_addr = dev->base_addr;
162 		ifr->ifr_map.irq       = dev->irq;
163 		ifr->ifr_map.dma       = dev->dma;
164 		ifr->ifr_map.port      = dev->if_port;
165 		return 0;
166 
167 	case SIOCGIFINDEX:
168 		ifr->ifr_ifindex = dev->ifindex;
169 		return 0;
170 
171 	case SIOCGIFTXQLEN:
172 		ifr->ifr_qlen = dev->tx_queue_len;
173 		return 0;
174 
175 	default:
176 		/* dev_ioctl() should ensure this case
177 		 * is never reached
178 		 */
179 		WARN_ON(1);
180 		err = -ENOTTY;
181 		break;
182 
183 	}
184 	return err;
185 }
186 
187 static int net_hwtstamp_validate(struct ifreq *ifr)
188 {
189 	struct hwtstamp_config cfg;
190 	enum hwtstamp_tx_types tx_type;
191 	enum hwtstamp_rx_filters rx_filter;
192 	int tx_type_valid = 0;
193 	int rx_filter_valid = 0;
194 
195 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
196 		return -EFAULT;
197 
198 	if (cfg.flags) /* reserved for future extensions */
199 		return -EINVAL;
200 
201 	tx_type = cfg.tx_type;
202 	rx_filter = cfg.rx_filter;
203 
204 	switch (tx_type) {
205 	case HWTSTAMP_TX_OFF:
206 	case HWTSTAMP_TX_ON:
207 	case HWTSTAMP_TX_ONESTEP_SYNC:
208 		tx_type_valid = 1;
209 		break;
210 	}
211 
212 	switch (rx_filter) {
213 	case HWTSTAMP_FILTER_NONE:
214 	case HWTSTAMP_FILTER_ALL:
215 	case HWTSTAMP_FILTER_SOME:
216 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
217 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
219 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
220 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
222 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
223 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
225 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
226 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
227 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
228 	case HWTSTAMP_FILTER_NTP_ALL:
229 		rx_filter_valid = 1;
230 		break;
231 	}
232 
233 	if (!tx_type_valid || !rx_filter_valid)
234 		return -ERANGE;
235 
236 	return 0;
237 }
238 
239 /*
240  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
241  */
242 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
243 {
244 	int err;
245 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
246 	const struct net_device_ops *ops;
247 
248 	if (!dev)
249 		return -ENODEV;
250 
251 	ops = dev->netdev_ops;
252 
253 	switch (cmd) {
254 	case SIOCSIFFLAGS:	/* Set interface flags */
255 		return dev_change_flags(dev, ifr->ifr_flags);
256 
257 	case SIOCSIFMETRIC:	/* Set the metric on the interface
258 				   (currently unused) */
259 		return -EOPNOTSUPP;
260 
261 	case SIOCSIFMTU:	/* Set the MTU of a device */
262 		return dev_set_mtu(dev, ifr->ifr_mtu);
263 
264 	case SIOCSIFHWADDR:
265 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
266 
267 	case SIOCSIFHWBROADCAST:
268 		if (ifr->ifr_hwaddr.sa_family != dev->type)
269 			return -EINVAL;
270 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
271 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
272 			   (size_t)dev->addr_len));
273 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
274 		return 0;
275 
276 	case SIOCSIFMAP:
277 		if (ops->ndo_set_config) {
278 			if (!netif_device_present(dev))
279 				return -ENODEV;
280 			return ops->ndo_set_config(dev, &ifr->ifr_map);
281 		}
282 		return -EOPNOTSUPP;
283 
284 	case SIOCADDMULTI:
285 		if (!ops->ndo_set_rx_mode ||
286 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
287 			return -EINVAL;
288 		if (!netif_device_present(dev))
289 			return -ENODEV;
290 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
291 
292 	case SIOCDELMULTI:
293 		if (!ops->ndo_set_rx_mode ||
294 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
295 			return -EINVAL;
296 		if (!netif_device_present(dev))
297 			return -ENODEV;
298 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
299 
300 	case SIOCSIFTXQLEN:
301 		if (ifr->ifr_qlen < 0)
302 			return -EINVAL;
303 		dev->tx_queue_len = ifr->ifr_qlen;
304 		return 0;
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 		/* fall through */
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 = -EOPNOTSUPP;
337 			if (ops->ndo_do_ioctl) {
338 				if (netif_device_present(dev))
339 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
340 				else
341 					err = -ENODEV;
342 			}
343 		} else
344 			err = -EINVAL;
345 
346 	}
347 	return err;
348 }
349 
350 /**
351  *	dev_load 	- load a network module
352  *	@net: the applicable net namespace
353  *	@name: name of interface
354  *
355  *	If a network interface is not present and the process has suitable
356  *	privileges this function loads the module. If module loading is not
357  *	available in this kernel then it becomes a nop.
358  */
359 
360 void dev_load(struct net *net, const char *name)
361 {
362 	struct net_device *dev;
363 	int no_module;
364 
365 	rcu_read_lock();
366 	dev = dev_get_by_name_rcu(net, name);
367 	rcu_read_unlock();
368 
369 	no_module = !dev;
370 	if (no_module && capable(CAP_NET_ADMIN))
371 		no_module = request_module("netdev-%s", name);
372 	if (no_module && capable(CAP_SYS_MODULE))
373 		request_module("%s", name);
374 }
375 EXPORT_SYMBOL(dev_load);
376 
377 /*
378  *	This function handles all "interface"-type I/O control requests. The actual
379  *	'doing' part of this is dev_ifsioc above.
380  */
381 
382 /**
383  *	dev_ioctl	-	network device ioctl
384  *	@net: the applicable net namespace
385  *	@cmd: command to issue
386  *	@arg: pointer to a struct ifreq in user space
387  *
388  *	Issue ioctl functions to devices. This is normally called by the
389  *	user space syscall interfaces but can sometimes be useful for
390  *	other purposes. The return value is the return from the syscall if
391  *	positive or a negative errno code on error.
392  */
393 
394 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
395 {
396 	struct ifreq ifr;
397 	int ret;
398 	char *colon;
399 
400 	/* One special case: SIOCGIFCONF takes ifconf argument
401 	   and requires shared lock, because it sleeps writing
402 	   to user space.
403 	 */
404 
405 	if (cmd == SIOCGIFCONF) {
406 		rtnl_lock();
407 		ret = dev_ifconf(net, (char __user *) arg);
408 		rtnl_unlock();
409 		return ret;
410 	}
411 	if (cmd == SIOCGIFNAME)
412 		return dev_ifname(net, (struct ifreq __user *)arg);
413 
414 	/*
415 	 * Take care of Wireless Extensions. Unfortunately struct iwreq
416 	 * isn't a proper subset of struct ifreq (it's 8 byte shorter)
417 	 * so we need to treat it specially, otherwise applications may
418 	 * fault if the struct they're passing happens to land at the
419 	 * end of a mapped page.
420 	 */
421 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
422 		struct iwreq iwr;
423 
424 		if (copy_from_user(&iwr, arg, sizeof(iwr)))
425 			return -EFAULT;
426 
427 		return wext_handle_ioctl(net, &iwr, cmd, arg);
428 	}
429 
430 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
431 		return -EFAULT;
432 
433 	ifr.ifr_name[IFNAMSIZ-1] = 0;
434 
435 	colon = strchr(ifr.ifr_name, ':');
436 	if (colon)
437 		*colon = 0;
438 
439 	/*
440 	 *	See which interface the caller is talking about.
441 	 */
442 
443 	switch (cmd) {
444 	/*
445 	 *	These ioctl calls:
446 	 *	- can be done by all.
447 	 *	- atomic and do not require locking.
448 	 *	- return a value
449 	 */
450 	case SIOCGIFFLAGS:
451 	case SIOCGIFMETRIC:
452 	case SIOCGIFMTU:
453 	case SIOCGIFHWADDR:
454 	case SIOCGIFSLAVE:
455 	case SIOCGIFMAP:
456 	case SIOCGIFINDEX:
457 	case SIOCGIFTXQLEN:
458 		dev_load(net, ifr.ifr_name);
459 		rcu_read_lock();
460 		ret = dev_ifsioc_locked(net, &ifr, cmd);
461 		rcu_read_unlock();
462 		if (!ret) {
463 			if (colon)
464 				*colon = ':';
465 			if (copy_to_user(arg, &ifr,
466 					 sizeof(struct ifreq)))
467 				ret = -EFAULT;
468 		}
469 		return ret;
470 
471 	case SIOCETHTOOL:
472 		dev_load(net, ifr.ifr_name);
473 		rtnl_lock();
474 		ret = dev_ethtool(net, &ifr);
475 		rtnl_unlock();
476 		if (!ret) {
477 			if (colon)
478 				*colon = ':';
479 			if (copy_to_user(arg, &ifr,
480 					 sizeof(struct ifreq)))
481 				ret = -EFAULT;
482 		}
483 		return ret;
484 
485 	/*
486 	 *	These ioctl calls:
487 	 *	- require superuser power.
488 	 *	- require strict serialization.
489 	 *	- return a value
490 	 */
491 	case SIOCGMIIPHY:
492 	case SIOCGMIIREG:
493 	case SIOCSIFNAME:
494 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
495 			return -EPERM;
496 		dev_load(net, ifr.ifr_name);
497 		rtnl_lock();
498 		ret = dev_ifsioc(net, &ifr, cmd);
499 		rtnl_unlock();
500 		if (!ret) {
501 			if (colon)
502 				*colon = ':';
503 			if (copy_to_user(arg, &ifr,
504 					 sizeof(struct ifreq)))
505 				ret = -EFAULT;
506 		}
507 		return ret;
508 
509 	/*
510 	 *	These ioctl calls:
511 	 *	- require superuser power.
512 	 *	- require strict serialization.
513 	 *	- do not return a value
514 	 */
515 	case SIOCSIFMAP:
516 	case SIOCSIFTXQLEN:
517 		if (!capable(CAP_NET_ADMIN))
518 			return -EPERM;
519 		/* fall through */
520 	/*
521 	 *	These ioctl calls:
522 	 *	- require local superuser power.
523 	 *	- require strict serialization.
524 	 *	- do not return a value
525 	 */
526 	case SIOCSIFFLAGS:
527 	case SIOCSIFMETRIC:
528 	case SIOCSIFMTU:
529 	case SIOCSIFHWADDR:
530 	case SIOCSIFSLAVE:
531 	case SIOCADDMULTI:
532 	case SIOCDELMULTI:
533 	case SIOCSIFHWBROADCAST:
534 	case SIOCSMIIREG:
535 	case SIOCBONDENSLAVE:
536 	case SIOCBONDRELEASE:
537 	case SIOCBONDSETHWADDR:
538 	case SIOCBONDCHANGEACTIVE:
539 	case SIOCBRADDIF:
540 	case SIOCBRDELIF:
541 	case SIOCSHWTSTAMP:
542 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
543 			return -EPERM;
544 		/* fall through */
545 	case SIOCBONDSLAVEINFOQUERY:
546 	case SIOCBONDINFOQUERY:
547 		dev_load(net, ifr.ifr_name);
548 		rtnl_lock();
549 		ret = dev_ifsioc(net, &ifr, cmd);
550 		rtnl_unlock();
551 		return ret;
552 
553 	case SIOCGIFMEM:
554 		/* Get the per device memory space. We can add this but
555 		 * currently do not support it */
556 	case SIOCSIFMEM:
557 		/* Set the per device memory buffer space.
558 		 * Not applicable in our case */
559 	case SIOCSIFLINK:
560 		return -ENOTTY;
561 
562 	/*
563 	 *	Unknown or private ioctl.
564 	 */
565 	default:
566 		if (cmd == SIOCWANDEV ||
567 		    cmd == SIOCGHWTSTAMP ||
568 		    (cmd >= SIOCDEVPRIVATE &&
569 		     cmd <= SIOCDEVPRIVATE + 15)) {
570 			dev_load(net, ifr.ifr_name);
571 			rtnl_lock();
572 			ret = dev_ifsioc(net, &ifr, cmd);
573 			rtnl_unlock();
574 			if (!ret && copy_to_user(arg, &ifr,
575 						 sizeof(struct ifreq)))
576 				ret = -EFAULT;
577 			return ret;
578 		}
579 		return -ENOTTY;
580 	}
581 }
582