xref: /openbmc/linux/net/core/dev_ioctl.c (revision a977d045)
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 		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
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 		dev->tx_queue_len = ifr->ifr_qlen;
305 		return 0;
306 
307 	case SIOCSIFNAME:
308 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
309 		return dev_change_name(dev, ifr->ifr_newname);
310 
311 	case SIOCSHWTSTAMP:
312 		err = net_hwtstamp_validate(ifr);
313 		if (err)
314 			return err;
315 		/* fall through */
316 
317 	/*
318 	 *	Unknown or private ioctl
319 	 */
320 	default:
321 		if ((cmd >= SIOCDEVPRIVATE &&
322 		    cmd <= SIOCDEVPRIVATE + 15) ||
323 		    cmd == SIOCBONDENSLAVE ||
324 		    cmd == SIOCBONDRELEASE ||
325 		    cmd == SIOCBONDSETHWADDR ||
326 		    cmd == SIOCBONDSLAVEINFOQUERY ||
327 		    cmd == SIOCBONDINFOQUERY ||
328 		    cmd == SIOCBONDCHANGEACTIVE ||
329 		    cmd == SIOCGMIIPHY ||
330 		    cmd == SIOCGMIIREG ||
331 		    cmd == SIOCSMIIREG ||
332 		    cmd == SIOCBRADDIF ||
333 		    cmd == SIOCBRDELIF ||
334 		    cmd == SIOCSHWTSTAMP ||
335 		    cmd == SIOCGHWTSTAMP ||
336 		    cmd == SIOCWANDEV) {
337 			err = -EOPNOTSUPP;
338 			if (ops->ndo_do_ioctl) {
339 				if (netif_device_present(dev))
340 					err = ops->ndo_do_ioctl(dev, ifr, cmd);
341 				else
342 					err = -ENODEV;
343 			}
344 		} else
345 			err = -EINVAL;
346 
347 	}
348 	return err;
349 }
350 
351 /**
352  *	dev_load 	- load a network module
353  *	@net: the applicable net namespace
354  *	@name: name of interface
355  *
356  *	If a network interface is not present and the process has suitable
357  *	privileges this function loads the module. If module loading is not
358  *	available in this kernel then it becomes a nop.
359  */
360 
361 void dev_load(struct net *net, const char *name)
362 {
363 	struct net_device *dev;
364 	int no_module;
365 
366 	rcu_read_lock();
367 	dev = dev_get_by_name_rcu(net, name);
368 	rcu_read_unlock();
369 
370 	no_module = !dev;
371 	if (no_module && capable(CAP_NET_ADMIN))
372 		no_module = request_module("netdev-%s", name);
373 	if (no_module && capable(CAP_SYS_MODULE))
374 		request_module("%s", name);
375 }
376 EXPORT_SYMBOL(dev_load);
377 
378 /*
379  *	This function handles all "interface"-type I/O control requests. The actual
380  *	'doing' part of this is dev_ifsioc above.
381  */
382 
383 /**
384  *	dev_ioctl	-	network device ioctl
385  *	@net: the applicable net namespace
386  *	@cmd: command to issue
387  *	@arg: pointer to a struct ifreq in user space
388  *
389  *	Issue ioctl functions to devices. This is normally called by the
390  *	user space syscall interfaces but can sometimes be useful for
391  *	other purposes. The return value is the return from the syscall if
392  *	positive or a negative errno code on error.
393  */
394 
395 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
396 {
397 	struct ifreq ifr;
398 	int ret;
399 	char *colon;
400 
401 	/* One special case: SIOCGIFCONF takes ifconf argument
402 	   and requires shared lock, because it sleeps writing
403 	   to user space.
404 	 */
405 
406 	if (cmd == SIOCGIFCONF) {
407 		rtnl_lock();
408 		ret = dev_ifconf(net, (char __user *) arg);
409 		rtnl_unlock();
410 		return ret;
411 	}
412 	if (cmd == SIOCGIFNAME)
413 		return dev_ifname(net, (struct ifreq __user *)arg);
414 
415 	/*
416 	 * Take care of Wireless Extensions. Unfortunately struct iwreq
417 	 * isn't a proper subset of struct ifreq (it's 8 byte shorter)
418 	 * so we need to treat it specially, otherwise applications may
419 	 * fault if the struct they're passing happens to land at the
420 	 * end of a mapped page.
421 	 */
422 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
423 		struct iwreq iwr;
424 
425 		if (copy_from_user(&iwr, arg, sizeof(iwr)))
426 			return -EFAULT;
427 
428 		iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
429 
430 		return wext_handle_ioctl(net, &iwr, cmd, arg);
431 	}
432 
433 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
434 		return -EFAULT;
435 
436 	ifr.ifr_name[IFNAMSIZ-1] = 0;
437 
438 	colon = strchr(ifr.ifr_name, ':');
439 	if (colon)
440 		*colon = 0;
441 
442 	/*
443 	 *	See which interface the caller is talking about.
444 	 */
445 
446 	switch (cmd) {
447 	/*
448 	 *	These ioctl calls:
449 	 *	- can be done by all.
450 	 *	- atomic and do not require locking.
451 	 *	- return a value
452 	 */
453 	case SIOCGIFFLAGS:
454 	case SIOCGIFMETRIC:
455 	case SIOCGIFMTU:
456 	case SIOCGIFHWADDR:
457 	case SIOCGIFSLAVE:
458 	case SIOCGIFMAP:
459 	case SIOCGIFINDEX:
460 	case SIOCGIFTXQLEN:
461 		dev_load(net, ifr.ifr_name);
462 		rcu_read_lock();
463 		ret = dev_ifsioc_locked(net, &ifr, cmd);
464 		rcu_read_unlock();
465 		if (!ret) {
466 			if (colon)
467 				*colon = ':';
468 			if (copy_to_user(arg, &ifr,
469 					 sizeof(struct ifreq)))
470 				ret = -EFAULT;
471 		}
472 		return ret;
473 
474 	case SIOCETHTOOL:
475 		dev_load(net, ifr.ifr_name);
476 		rtnl_lock();
477 		ret = dev_ethtool(net, &ifr);
478 		rtnl_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 	/*
489 	 *	These ioctl calls:
490 	 *	- require superuser power.
491 	 *	- require strict serialization.
492 	 *	- return a value
493 	 */
494 	case SIOCGMIIPHY:
495 	case SIOCGMIIREG:
496 	case SIOCSIFNAME:
497 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
498 			return -EPERM;
499 		dev_load(net, ifr.ifr_name);
500 		rtnl_lock();
501 		ret = dev_ifsioc(net, &ifr, cmd);
502 		rtnl_unlock();
503 		if (!ret) {
504 			if (colon)
505 				*colon = ':';
506 			if (copy_to_user(arg, &ifr,
507 					 sizeof(struct ifreq)))
508 				ret = -EFAULT;
509 		}
510 		return ret;
511 
512 	/*
513 	 *	These ioctl calls:
514 	 *	- require superuser power.
515 	 *	- require strict serialization.
516 	 *	- do not return a value
517 	 */
518 	case SIOCSIFMAP:
519 	case SIOCSIFTXQLEN:
520 		if (!capable(CAP_NET_ADMIN))
521 			return -EPERM;
522 		/* fall through */
523 	/*
524 	 *	These ioctl calls:
525 	 *	- require local superuser power.
526 	 *	- require strict serialization.
527 	 *	- do not return a value
528 	 */
529 	case SIOCSIFFLAGS:
530 	case SIOCSIFMETRIC:
531 	case SIOCSIFMTU:
532 	case SIOCSIFHWADDR:
533 	case SIOCSIFSLAVE:
534 	case SIOCADDMULTI:
535 	case SIOCDELMULTI:
536 	case SIOCSIFHWBROADCAST:
537 	case SIOCSMIIREG:
538 	case SIOCBONDENSLAVE:
539 	case SIOCBONDRELEASE:
540 	case SIOCBONDSETHWADDR:
541 	case SIOCBONDCHANGEACTIVE:
542 	case SIOCBRADDIF:
543 	case SIOCBRDELIF:
544 	case SIOCSHWTSTAMP:
545 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
546 			return -EPERM;
547 		/* fall through */
548 	case SIOCBONDSLAVEINFOQUERY:
549 	case SIOCBONDINFOQUERY:
550 		dev_load(net, ifr.ifr_name);
551 		rtnl_lock();
552 		ret = dev_ifsioc(net, &ifr, cmd);
553 		rtnl_unlock();
554 		return ret;
555 
556 	case SIOCGIFMEM:
557 		/* Get the per device memory space. We can add this but
558 		 * currently do not support it */
559 	case SIOCSIFMEM:
560 		/* Set the per device memory buffer space.
561 		 * Not applicable in our case */
562 	case SIOCSIFLINK:
563 		return -ENOTTY;
564 
565 	/*
566 	 *	Unknown or private ioctl.
567 	 */
568 	default:
569 		if (cmd == SIOCWANDEV ||
570 		    cmd == SIOCGHWTSTAMP ||
571 		    (cmd >= SIOCDEVPRIVATE &&
572 		     cmd <= SIOCDEVPRIVATE + 15)) {
573 			dev_load(net, ifr.ifr_name);
574 			rtnl_lock();
575 			ret = dev_ifsioc(net, &ifr, cmd);
576 			rtnl_unlock();
577 			if (!ret && copy_to_user(arg, &ifr,
578 						 sizeof(struct ifreq)))
579 				ret = -EFAULT;
580 			return ret;
581 		}
582 		return -ENOTTY;
583 	}
584 }
585