xref: /linux/net/core/rtnetlink.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Routing netlink socket interface: protocol independent part.
7  *
8  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
9  *
10  *		This program is free software; you can redistribute it and/or
11  *		modify it under the terms of the GNU General Public License
12  *		as published by the Free Software Foundation; either version
13  *		2 of the License, or (at your option) any later version.
14  *
15  *	Fixes:
16  *	Vitaly E. Lavrov		RTA_OK arithmetics was wrong.
17  */
18 
19 #include <linux/errno.h>
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/socket.h>
23 #include <linux/kernel.h>
24 #include <linux/timer.h>
25 #include <linux/string.h>
26 #include <linux/sockios.h>
27 #include <linux/net.h>
28 #include <linux/fcntl.h>
29 #include <linux/mm.h>
30 #include <linux/slab.h>
31 #include <linux/interrupt.h>
32 #include <linux/capability.h>
33 #include <linux/skbuff.h>
34 #include <linux/init.h>
35 #include <linux/security.h>
36 #include <linux/mutex.h>
37 #include <linux/if_addr.h>
38 #include <linux/nsproxy.h>
39 
40 #include <asm/uaccess.h>
41 #include <asm/system.h>
42 #include <asm/string.h>
43 
44 #include <linux/inet.h>
45 #include <linux/netdevice.h>
46 #include <net/ip.h>
47 #include <net/protocol.h>
48 #include <net/arp.h>
49 #include <net/route.h>
50 #include <net/udp.h>
51 #include <net/sock.h>
52 #include <net/pkt_sched.h>
53 #include <net/fib_rules.h>
54 #include <net/rtnetlink.h>
55 
56 struct rtnl_link
57 {
58 	rtnl_doit_func		doit;
59 	rtnl_dumpit_func	dumpit;
60 };
61 
62 static DEFINE_MUTEX(rtnl_mutex);
63 static struct sock *rtnl;
64 
65 void rtnl_lock(void)
66 {
67 	mutex_lock(&rtnl_mutex);
68 }
69 
70 void __rtnl_unlock(void)
71 {
72 	mutex_unlock(&rtnl_mutex);
73 }
74 
75 void rtnl_unlock(void)
76 {
77 	mutex_unlock(&rtnl_mutex);
78 	netdev_run_todo();
79 }
80 
81 int rtnl_trylock(void)
82 {
83 	return mutex_trylock(&rtnl_mutex);
84 }
85 
86 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
87 {
88 	memset(tb, 0, sizeof(struct rtattr*)*maxattr);
89 
90 	while (RTA_OK(rta, len)) {
91 		unsigned flavor = rta->rta_type;
92 		if (flavor && flavor <= maxattr)
93 			tb[flavor-1] = rta;
94 		rta = RTA_NEXT(rta, len);
95 	}
96 	return 0;
97 }
98 
99 int __rtattr_parse_nested_compat(struct rtattr *tb[], int maxattr,
100 				 struct rtattr *rta, int len)
101 {
102 	if (RTA_PAYLOAD(rta) < len)
103 		return -1;
104 	if (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) {
105 		rta = RTA_DATA(rta) + RTA_ALIGN(len);
106 		return rtattr_parse_nested(tb, maxattr, rta);
107 	}
108 	memset(tb, 0, sizeof(struct rtattr *) * maxattr);
109 	return 0;
110 }
111 
112 static struct rtnl_link *rtnl_msg_handlers[NPROTO];
113 
114 static inline int rtm_msgindex(int msgtype)
115 {
116 	int msgindex = msgtype - RTM_BASE;
117 
118 	/*
119 	 * msgindex < 0 implies someone tried to register a netlink
120 	 * control code. msgindex >= RTM_NR_MSGTYPES may indicate that
121 	 * the message type has not been added to linux/rtnetlink.h
122 	 */
123 	BUG_ON(msgindex < 0 || msgindex >= RTM_NR_MSGTYPES);
124 
125 	return msgindex;
126 }
127 
128 static rtnl_doit_func rtnl_get_doit(int protocol, int msgindex)
129 {
130 	struct rtnl_link *tab;
131 
132 	tab = rtnl_msg_handlers[protocol];
133 	if (tab == NULL || tab[msgindex].doit == NULL)
134 		tab = rtnl_msg_handlers[PF_UNSPEC];
135 
136 	return tab ? tab[msgindex].doit : NULL;
137 }
138 
139 static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex)
140 {
141 	struct rtnl_link *tab;
142 
143 	tab = rtnl_msg_handlers[protocol];
144 	if (tab == NULL || tab[msgindex].dumpit == NULL)
145 		tab = rtnl_msg_handlers[PF_UNSPEC];
146 
147 	return tab ? tab[msgindex].dumpit : NULL;
148 }
149 
150 /**
151  * __rtnl_register - Register a rtnetlink message type
152  * @protocol: Protocol family or PF_UNSPEC
153  * @msgtype: rtnetlink message type
154  * @doit: Function pointer called for each request message
155  * @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
156  *
157  * Registers the specified function pointers (at least one of them has
158  * to be non-NULL) to be called whenever a request message for the
159  * specified protocol family and message type is received.
160  *
161  * The special protocol family PF_UNSPEC may be used to define fallback
162  * function pointers for the case when no entry for the specific protocol
163  * family exists.
164  *
165  * Returns 0 on success or a negative error code.
166  */
167 int __rtnl_register(int protocol, int msgtype,
168 		    rtnl_doit_func doit, rtnl_dumpit_func dumpit)
169 {
170 	struct rtnl_link *tab;
171 	int msgindex;
172 
173 	BUG_ON(protocol < 0 || protocol >= NPROTO);
174 	msgindex = rtm_msgindex(msgtype);
175 
176 	tab = rtnl_msg_handlers[protocol];
177 	if (tab == NULL) {
178 		tab = kcalloc(RTM_NR_MSGTYPES, sizeof(*tab), GFP_KERNEL);
179 		if (tab == NULL)
180 			return -ENOBUFS;
181 
182 		rtnl_msg_handlers[protocol] = tab;
183 	}
184 
185 	if (doit)
186 		tab[msgindex].doit = doit;
187 
188 	if (dumpit)
189 		tab[msgindex].dumpit = dumpit;
190 
191 	return 0;
192 }
193 
194 EXPORT_SYMBOL_GPL(__rtnl_register);
195 
196 /**
197  * rtnl_register - Register a rtnetlink message type
198  *
199  * Identical to __rtnl_register() but panics on failure. This is useful
200  * as failure of this function is very unlikely, it can only happen due
201  * to lack of memory when allocating the chain to store all message
202  * handlers for a protocol. Meant for use in init functions where lack
203  * of memory implies no sense in continueing.
204  */
205 void rtnl_register(int protocol, int msgtype,
206 		   rtnl_doit_func doit, rtnl_dumpit_func dumpit)
207 {
208 	if (__rtnl_register(protocol, msgtype, doit, dumpit) < 0)
209 		panic("Unable to register rtnetlink message handler, "
210 		      "protocol = %d, message type = %d\n",
211 		      protocol, msgtype);
212 }
213 
214 EXPORT_SYMBOL_GPL(rtnl_register);
215 
216 /**
217  * rtnl_unregister - Unregister a rtnetlink message type
218  * @protocol: Protocol family or PF_UNSPEC
219  * @msgtype: rtnetlink message type
220  *
221  * Returns 0 on success or a negative error code.
222  */
223 int rtnl_unregister(int protocol, int msgtype)
224 {
225 	int msgindex;
226 
227 	BUG_ON(protocol < 0 || protocol >= NPROTO);
228 	msgindex = rtm_msgindex(msgtype);
229 
230 	if (rtnl_msg_handlers[protocol] == NULL)
231 		return -ENOENT;
232 
233 	rtnl_msg_handlers[protocol][msgindex].doit = NULL;
234 	rtnl_msg_handlers[protocol][msgindex].dumpit = NULL;
235 
236 	return 0;
237 }
238 
239 EXPORT_SYMBOL_GPL(rtnl_unregister);
240 
241 /**
242  * rtnl_unregister_all - Unregister all rtnetlink message type of a protocol
243  * @protocol : Protocol family or PF_UNSPEC
244  *
245  * Identical to calling rtnl_unregster() for all registered message types
246  * of a certain protocol family.
247  */
248 void rtnl_unregister_all(int protocol)
249 {
250 	BUG_ON(protocol < 0 || protocol >= NPROTO);
251 
252 	kfree(rtnl_msg_handlers[protocol]);
253 	rtnl_msg_handlers[protocol] = NULL;
254 }
255 
256 EXPORT_SYMBOL_GPL(rtnl_unregister_all);
257 
258 static LIST_HEAD(link_ops);
259 
260 /**
261  * __rtnl_link_register - Register rtnl_link_ops with rtnetlink.
262  * @ops: struct rtnl_link_ops * to register
263  *
264  * The caller must hold the rtnl_mutex. This function should be used
265  * by drivers that create devices during module initialization. It
266  * must be called before registering the devices.
267  *
268  * Returns 0 on success or a negative error code.
269  */
270 int __rtnl_link_register(struct rtnl_link_ops *ops)
271 {
272 	if (!ops->dellink)
273 		ops->dellink = unregister_netdevice;
274 
275 	list_add_tail(&ops->list, &link_ops);
276 	return 0;
277 }
278 
279 EXPORT_SYMBOL_GPL(__rtnl_link_register);
280 
281 /**
282  * rtnl_link_register - Register rtnl_link_ops with rtnetlink.
283  * @ops: struct rtnl_link_ops * to register
284  *
285  * Returns 0 on success or a negative error code.
286  */
287 int rtnl_link_register(struct rtnl_link_ops *ops)
288 {
289 	int err;
290 
291 	rtnl_lock();
292 	err = __rtnl_link_register(ops);
293 	rtnl_unlock();
294 	return err;
295 }
296 
297 EXPORT_SYMBOL_GPL(rtnl_link_register);
298 
299 /**
300  * __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
301  * @ops: struct rtnl_link_ops * to unregister
302  *
303  * The caller must hold the rtnl_mutex.
304  */
305 void __rtnl_link_unregister(struct rtnl_link_ops *ops)
306 {
307 	struct net_device *dev, *n;
308 	struct net *net;
309 
310 	for_each_net(net) {
311 		for_each_netdev_safe(net, dev, n) {
312 			if (dev->rtnl_link_ops == ops)
313 				ops->dellink(dev);
314 		}
315 	}
316 	list_del(&ops->list);
317 }
318 
319 EXPORT_SYMBOL_GPL(__rtnl_link_unregister);
320 
321 /**
322  * rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
323  * @ops: struct rtnl_link_ops * to unregister
324  */
325 void rtnl_link_unregister(struct rtnl_link_ops *ops)
326 {
327 	rtnl_lock();
328 	__rtnl_link_unregister(ops);
329 	rtnl_unlock();
330 }
331 
332 EXPORT_SYMBOL_GPL(rtnl_link_unregister);
333 
334 static const struct rtnl_link_ops *rtnl_link_ops_get(const char *kind)
335 {
336 	const struct rtnl_link_ops *ops;
337 
338 	list_for_each_entry(ops, &link_ops, list) {
339 		if (!strcmp(ops->kind, kind))
340 			return ops;
341 	}
342 	return NULL;
343 }
344 
345 static size_t rtnl_link_get_size(const struct net_device *dev)
346 {
347 	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
348 	size_t size;
349 
350 	if (!ops)
351 		return 0;
352 
353 	size = nlmsg_total_size(sizeof(struct nlattr)) + /* IFLA_LINKINFO */
354 	       nlmsg_total_size(strlen(ops->kind) + 1);	 /* IFLA_INFO_KIND */
355 
356 	if (ops->get_size)
357 		/* IFLA_INFO_DATA + nested data */
358 		size += nlmsg_total_size(sizeof(struct nlattr)) +
359 			ops->get_size(dev);
360 
361 	if (ops->get_xstats_size)
362 		size += ops->get_xstats_size(dev);	/* IFLA_INFO_XSTATS */
363 
364 	return size;
365 }
366 
367 static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
368 {
369 	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
370 	struct nlattr *linkinfo, *data;
371 	int err = -EMSGSIZE;
372 
373 	linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
374 	if (linkinfo == NULL)
375 		goto out;
376 
377 	if (nla_put_string(skb, IFLA_INFO_KIND, ops->kind) < 0)
378 		goto err_cancel_link;
379 	if (ops->fill_xstats) {
380 		err = ops->fill_xstats(skb, dev);
381 		if (err < 0)
382 			goto err_cancel_link;
383 	}
384 	if (ops->fill_info) {
385 		data = nla_nest_start(skb, IFLA_INFO_DATA);
386 		if (data == NULL)
387 			goto err_cancel_link;
388 		err = ops->fill_info(skb, dev);
389 		if (err < 0)
390 			goto err_cancel_data;
391 		nla_nest_end(skb, data);
392 	}
393 
394 	nla_nest_end(skb, linkinfo);
395 	return 0;
396 
397 err_cancel_data:
398 	nla_nest_cancel(skb, data);
399 err_cancel_link:
400 	nla_nest_cancel(skb, linkinfo);
401 out:
402 	return err;
403 }
404 
405 static const int rtm_min[RTM_NR_FAMILIES] =
406 {
407 	[RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
408 	[RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
409 	[RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
410 	[RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
411 	[RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
412 	[RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
413 	[RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
414 	[RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
415 	[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
416 	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
417 };
418 
419 static const int rta_max[RTM_NR_FAMILIES] =
420 {
421 	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
422 	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
423 	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
424 	[RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,
425 	[RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
426 	[RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
427 	[RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
428 	[RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
429 };
430 
431 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
432 {
433 	struct rtattr *rta;
434 	int size = RTA_LENGTH(attrlen);
435 
436 	rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
437 	rta->rta_type = attrtype;
438 	rta->rta_len = size;
439 	memcpy(RTA_DATA(rta), data, attrlen);
440 	memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
441 }
442 
443 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
444 {
445 	size_t ret = RTA_PAYLOAD(rta);
446 	char *src = RTA_DATA(rta);
447 
448 	if (ret > 0 && src[ret - 1] == '\0')
449 		ret--;
450 	if (size > 0) {
451 		size_t len = (ret >= size) ? size - 1 : ret;
452 		memset(dest, 0, size);
453 		memcpy(dest, src, len);
454 	}
455 	return ret;
456 }
457 
458 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
459 {
460 	int err = 0;
461 
462 	NETLINK_CB(skb).dst_group = group;
463 	if (echo)
464 		atomic_inc(&skb->users);
465 	netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
466 	if (echo)
467 		err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
468 	return err;
469 }
470 
471 int rtnl_unicast(struct sk_buff *skb, u32 pid)
472 {
473 	return nlmsg_unicast(rtnl, skb, pid);
474 }
475 
476 int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
477 		struct nlmsghdr *nlh, gfp_t flags)
478 {
479 	int report = 0;
480 
481 	if (nlh)
482 		report = nlmsg_report(nlh);
483 
484 	return nlmsg_notify(rtnl, skb, pid, group, report, flags);
485 }
486 
487 void rtnl_set_sk_err(u32 group, int error)
488 {
489 	netlink_set_err(rtnl, 0, group, error);
490 }
491 
492 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
493 {
494 	struct nlattr *mx;
495 	int i, valid = 0;
496 
497 	mx = nla_nest_start(skb, RTA_METRICS);
498 	if (mx == NULL)
499 		return -ENOBUFS;
500 
501 	for (i = 0; i < RTAX_MAX; i++) {
502 		if (metrics[i]) {
503 			valid++;
504 			NLA_PUT_U32(skb, i+1, metrics[i]);
505 		}
506 	}
507 
508 	if (!valid) {
509 		nla_nest_cancel(skb, mx);
510 		return 0;
511 	}
512 
513 	return nla_nest_end(skb, mx);
514 
515 nla_put_failure:
516 	return nla_nest_cancel(skb, mx);
517 }
518 
519 int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
520 		       u32 ts, u32 tsage, long expires, u32 error)
521 {
522 	struct rta_cacheinfo ci = {
523 		.rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
524 		.rta_used = dst->__use,
525 		.rta_clntref = atomic_read(&(dst->__refcnt)),
526 		.rta_error = error,
527 		.rta_id =  id,
528 		.rta_ts = ts,
529 		.rta_tsage = tsage,
530 	};
531 
532 	if (expires)
533 		ci.rta_expires = jiffies_to_clock_t(expires);
534 
535 	return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
536 }
537 
538 EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);
539 
540 static void set_operstate(struct net_device *dev, unsigned char transition)
541 {
542 	unsigned char operstate = dev->operstate;
543 
544 	switch(transition) {
545 	case IF_OPER_UP:
546 		if ((operstate == IF_OPER_DORMANT ||
547 		     operstate == IF_OPER_UNKNOWN) &&
548 		    !netif_dormant(dev))
549 			operstate = IF_OPER_UP;
550 		break;
551 
552 	case IF_OPER_DORMANT:
553 		if (operstate == IF_OPER_UP ||
554 		    operstate == IF_OPER_UNKNOWN)
555 			operstate = IF_OPER_DORMANT;
556 		break;
557 	}
558 
559 	if (dev->operstate != operstate) {
560 		write_lock_bh(&dev_base_lock);
561 		dev->operstate = operstate;
562 		write_unlock_bh(&dev_base_lock);
563 		netdev_state_change(dev);
564 	}
565 }
566 
567 static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
568 				 struct net_device_stats *b)
569 {
570 	a->rx_packets = b->rx_packets;
571 	a->tx_packets = b->tx_packets;
572 	a->rx_bytes = b->rx_bytes;
573 	a->tx_bytes = b->tx_bytes;
574 	a->rx_errors = b->rx_errors;
575 	a->tx_errors = b->tx_errors;
576 	a->rx_dropped = b->rx_dropped;
577 	a->tx_dropped = b->tx_dropped;
578 
579 	a->multicast = b->multicast;
580 	a->collisions = b->collisions;
581 
582 	a->rx_length_errors = b->rx_length_errors;
583 	a->rx_over_errors = b->rx_over_errors;
584 	a->rx_crc_errors = b->rx_crc_errors;
585 	a->rx_frame_errors = b->rx_frame_errors;
586 	a->rx_fifo_errors = b->rx_fifo_errors;
587 	a->rx_missed_errors = b->rx_missed_errors;
588 
589 	a->tx_aborted_errors = b->tx_aborted_errors;
590 	a->tx_carrier_errors = b->tx_carrier_errors;
591 	a->tx_fifo_errors = b->tx_fifo_errors;
592 	a->tx_heartbeat_errors = b->tx_heartbeat_errors;
593 	a->tx_window_errors = b->tx_window_errors;
594 
595 	a->rx_compressed = b->rx_compressed;
596 	a->tx_compressed = b->tx_compressed;
597 };
598 
599 static inline size_t if_nlmsg_size(const struct net_device *dev)
600 {
601 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
602 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
603 	       + nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
604 	       + nla_total_size(sizeof(struct rtnl_link_ifmap))
605 	       + nla_total_size(sizeof(struct rtnl_link_stats))
606 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
607 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_BROADCAST */
608 	       + nla_total_size(4) /* IFLA_TXQLEN */
609 	       + nla_total_size(4) /* IFLA_WEIGHT */
610 	       + nla_total_size(4) /* IFLA_MTU */
611 	       + nla_total_size(4) /* IFLA_LINK */
612 	       + nla_total_size(4) /* IFLA_MASTER */
613 	       + nla_total_size(1) /* IFLA_OPERSTATE */
614 	       + nla_total_size(1) /* IFLA_LINKMODE */
615 	       + rtnl_link_get_size(dev); /* IFLA_LINKINFO */
616 }
617 
618 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
619 			    int type, u32 pid, u32 seq, u32 change,
620 			    unsigned int flags)
621 {
622 	struct ifinfomsg *ifm;
623 	struct nlmsghdr *nlh;
624 
625 	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
626 	if (nlh == NULL)
627 		return -EMSGSIZE;
628 
629 	ifm = nlmsg_data(nlh);
630 	ifm->ifi_family = AF_UNSPEC;
631 	ifm->__ifi_pad = 0;
632 	ifm->ifi_type = dev->type;
633 	ifm->ifi_index = dev->ifindex;
634 	ifm->ifi_flags = dev_get_flags(dev);
635 	ifm->ifi_change = change;
636 
637 	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
638 	NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
639 	NLA_PUT_U8(skb, IFLA_OPERSTATE,
640 		   netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
641 	NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
642 	NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
643 
644 	if (dev->ifindex != dev->iflink)
645 		NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
646 
647 	if (dev->master)
648 		NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
649 
650 	if (dev->qdisc_sleeping)
651 		NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
652 
653 	if (1) {
654 		struct rtnl_link_ifmap map = {
655 			.mem_start   = dev->mem_start,
656 			.mem_end     = dev->mem_end,
657 			.base_addr   = dev->base_addr,
658 			.irq         = dev->irq,
659 			.dma         = dev->dma,
660 			.port        = dev->if_port,
661 		};
662 		NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
663 	}
664 
665 	if (dev->addr_len) {
666 		NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
667 		NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
668 	}
669 
670 	if (dev->get_stats) {
671 		struct net_device_stats *stats = dev->get_stats(dev);
672 		if (stats) {
673 			struct nlattr *attr;
674 
675 			attr = nla_reserve(skb, IFLA_STATS,
676 					   sizeof(struct rtnl_link_stats));
677 			if (attr == NULL)
678 				goto nla_put_failure;
679 
680 			copy_rtnl_link_stats(nla_data(attr), stats);
681 		}
682 	}
683 
684 	if (dev->rtnl_link_ops) {
685 		if (rtnl_link_fill(skb, dev) < 0)
686 			goto nla_put_failure;
687 	}
688 
689 	return nlmsg_end(skb, nlh);
690 
691 nla_put_failure:
692 	nlmsg_cancel(skb, nlh);
693 	return -EMSGSIZE;
694 }
695 
696 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
697 {
698 	struct net *net = skb->sk->sk_net;
699 	int idx;
700 	int s_idx = cb->args[0];
701 	struct net_device *dev;
702 
703 	idx = 0;
704 	for_each_netdev(net, dev) {
705 		if (idx < s_idx)
706 			goto cont;
707 		if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
708 				     NETLINK_CB(cb->skb).pid,
709 				     cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
710 			break;
711 cont:
712 		idx++;
713 	}
714 	cb->args[0] = idx;
715 
716 	return skb->len;
717 }
718 
719 const struct nla_policy ifla_policy[IFLA_MAX+1] = {
720 	[IFLA_IFNAME]		= { .type = NLA_STRING, .len = IFNAMSIZ-1 },
721 	[IFLA_ADDRESS]		= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
722 	[IFLA_BROADCAST]	= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
723 	[IFLA_MAP]		= { .len = sizeof(struct rtnl_link_ifmap) },
724 	[IFLA_MTU]		= { .type = NLA_U32 },
725 	[IFLA_TXQLEN]		= { .type = NLA_U32 },
726 	[IFLA_WEIGHT]		= { .type = NLA_U32 },
727 	[IFLA_OPERSTATE]	= { .type = NLA_U8 },
728 	[IFLA_LINKMODE]		= { .type = NLA_U8 },
729 	[IFLA_NET_NS_PID]	= { .type = NLA_U32 },
730 };
731 
732 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
733 	[IFLA_INFO_KIND]	= { .type = NLA_STRING },
734 	[IFLA_INFO_DATA]	= { .type = NLA_NESTED },
735 };
736 
737 static struct net *get_net_ns_by_pid(pid_t pid)
738 {
739 	struct task_struct *tsk;
740 	struct net *net;
741 
742 	/* Lookup the network namespace */
743 	net = ERR_PTR(-ESRCH);
744 	rcu_read_lock();
745 	tsk = find_task_by_pid(pid);
746 	if (tsk) {
747 		task_lock(tsk);
748 		if (tsk->nsproxy)
749 			net = get_net(tsk->nsproxy->net_ns);
750 		task_unlock(tsk);
751 	}
752 	rcu_read_unlock();
753 	return net;
754 }
755 
756 static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
757 		      struct nlattr **tb, char *ifname, int modified)
758 {
759 	int send_addr_notify = 0;
760 	int err;
761 
762 	if (tb[IFLA_NET_NS_PID]) {
763 		struct net *net;
764 		net = get_net_ns_by_pid(nla_get_u32(tb[IFLA_NET_NS_PID]));
765 		if (IS_ERR(net)) {
766 			err = PTR_ERR(net);
767 			goto errout;
768 		}
769 		err = dev_change_net_namespace(dev, net, ifname);
770 		put_net(net);
771 		if (err)
772 			goto errout;
773 		modified = 1;
774 	}
775 
776 	if (tb[IFLA_MAP]) {
777 		struct rtnl_link_ifmap *u_map;
778 		struct ifmap k_map;
779 
780 		if (!dev->set_config) {
781 			err = -EOPNOTSUPP;
782 			goto errout;
783 		}
784 
785 		if (!netif_device_present(dev)) {
786 			err = -ENODEV;
787 			goto errout;
788 		}
789 
790 		u_map = nla_data(tb[IFLA_MAP]);
791 		k_map.mem_start = (unsigned long) u_map->mem_start;
792 		k_map.mem_end = (unsigned long) u_map->mem_end;
793 		k_map.base_addr = (unsigned short) u_map->base_addr;
794 		k_map.irq = (unsigned char) u_map->irq;
795 		k_map.dma = (unsigned char) u_map->dma;
796 		k_map.port = (unsigned char) u_map->port;
797 
798 		err = dev->set_config(dev, &k_map);
799 		if (err < 0)
800 			goto errout;
801 
802 		modified = 1;
803 	}
804 
805 	if (tb[IFLA_ADDRESS]) {
806 		struct sockaddr *sa;
807 		int len;
808 
809 		if (!dev->set_mac_address) {
810 			err = -EOPNOTSUPP;
811 			goto errout;
812 		}
813 
814 		if (!netif_device_present(dev)) {
815 			err = -ENODEV;
816 			goto errout;
817 		}
818 
819 		len = sizeof(sa_family_t) + dev->addr_len;
820 		sa = kmalloc(len, GFP_KERNEL);
821 		if (!sa) {
822 			err = -ENOMEM;
823 			goto errout;
824 		}
825 		sa->sa_family = dev->type;
826 		memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
827 		       dev->addr_len);
828 		err = dev->set_mac_address(dev, sa);
829 		kfree(sa);
830 		if (err)
831 			goto errout;
832 		send_addr_notify = 1;
833 		modified = 1;
834 	}
835 
836 	if (tb[IFLA_MTU]) {
837 		err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
838 		if (err < 0)
839 			goto errout;
840 		modified = 1;
841 	}
842 
843 	/*
844 	 * Interface selected by interface index but interface
845 	 * name provided implies that a name change has been
846 	 * requested.
847 	 */
848 	if (ifm->ifi_index > 0 && ifname[0]) {
849 		err = dev_change_name(dev, ifname);
850 		if (err < 0)
851 			goto errout;
852 		modified = 1;
853 	}
854 
855 	if (tb[IFLA_BROADCAST]) {
856 		nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
857 		send_addr_notify = 1;
858 	}
859 
860 	if (ifm->ifi_flags || ifm->ifi_change) {
861 		unsigned int flags = ifm->ifi_flags;
862 
863 		/* bugwards compatibility: ifi_change == 0 is treated as ~0 */
864 		if (ifm->ifi_change)
865 			flags = (flags & ifm->ifi_change) |
866 				(dev->flags & ~ifm->ifi_change);
867 		dev_change_flags(dev, flags);
868 	}
869 
870 	if (tb[IFLA_TXQLEN])
871 		dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
872 
873 	if (tb[IFLA_OPERSTATE])
874 		set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
875 
876 	if (tb[IFLA_LINKMODE]) {
877 		write_lock_bh(&dev_base_lock);
878 		dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
879 		write_unlock_bh(&dev_base_lock);
880 	}
881 
882 	err = 0;
883 
884 errout:
885 	if (err < 0 && modified && net_ratelimit())
886 		printk(KERN_WARNING "A link change request failed with "
887 		       "some changes comitted already. Interface %s may "
888 		       "have been left with an inconsistent configuration, "
889 		       "please check.\n", dev->name);
890 
891 	if (send_addr_notify)
892 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
893 	return err;
894 }
895 
896 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
897 {
898 	struct net *net = skb->sk->sk_net;
899 	struct ifinfomsg *ifm;
900 	struct net_device *dev;
901 	int err;
902 	struct nlattr *tb[IFLA_MAX+1];
903 	char ifname[IFNAMSIZ];
904 
905 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
906 	if (err < 0)
907 		goto errout;
908 
909 	if (tb[IFLA_IFNAME])
910 		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
911 	else
912 		ifname[0] = '\0';
913 
914 	err = -EINVAL;
915 	ifm = nlmsg_data(nlh);
916 	if (ifm->ifi_index > 0)
917 		dev = dev_get_by_index(net, ifm->ifi_index);
918 	else if (tb[IFLA_IFNAME])
919 		dev = dev_get_by_name(net, ifname);
920 	else
921 		goto errout;
922 
923 	if (dev == NULL) {
924 		err = -ENODEV;
925 		goto errout;
926 	}
927 
928 	if (tb[IFLA_ADDRESS] &&
929 	    nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
930 		goto errout_dev;
931 
932 	if (tb[IFLA_BROADCAST] &&
933 	    nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
934 		goto errout_dev;
935 
936 	err = do_setlink(dev, ifm, tb, ifname, 0);
937 errout_dev:
938 	dev_put(dev);
939 errout:
940 	return err;
941 }
942 
943 static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
944 {
945 	struct net *net = skb->sk->sk_net;
946 	const struct rtnl_link_ops *ops;
947 	struct net_device *dev;
948 	struct ifinfomsg *ifm;
949 	char ifname[IFNAMSIZ];
950 	struct nlattr *tb[IFLA_MAX+1];
951 	int err;
952 
953 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
954 	if (err < 0)
955 		return err;
956 
957 	if (tb[IFLA_IFNAME])
958 		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
959 
960 	ifm = nlmsg_data(nlh);
961 	if (ifm->ifi_index > 0)
962 		dev = __dev_get_by_index(net, ifm->ifi_index);
963 	else if (tb[IFLA_IFNAME])
964 		dev = __dev_get_by_name(net, ifname);
965 	else
966 		return -EINVAL;
967 
968 	if (!dev)
969 		return -ENODEV;
970 
971 	ops = dev->rtnl_link_ops;
972 	if (!ops)
973 		return -EOPNOTSUPP;
974 
975 	ops->dellink(dev);
976 	return 0;
977 }
978 
979 struct net_device *rtnl_create_link(struct net *net, char *ifname,
980 		const struct rtnl_link_ops *ops, struct nlattr *tb[])
981 {
982 	int err;
983 	struct net_device *dev;
984 
985 	err = -ENOMEM;
986 	dev = alloc_netdev(ops->priv_size, ifname, ops->setup);
987 	if (!dev)
988 		goto err;
989 
990 	if (strchr(dev->name, '%')) {
991 		err = dev_alloc_name(dev, dev->name);
992 		if (err < 0)
993 			goto err_free;
994 	}
995 
996 	dev->nd_net = net;
997 	dev->rtnl_link_ops = ops;
998 
999 	if (tb[IFLA_MTU])
1000 		dev->mtu = nla_get_u32(tb[IFLA_MTU]);
1001 	if (tb[IFLA_ADDRESS])
1002 		memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]),
1003 				nla_len(tb[IFLA_ADDRESS]));
1004 	if (tb[IFLA_BROADCAST])
1005 		memcpy(dev->broadcast, nla_data(tb[IFLA_BROADCAST]),
1006 				nla_len(tb[IFLA_BROADCAST]));
1007 	if (tb[IFLA_TXQLEN])
1008 		dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
1009 	if (tb[IFLA_OPERSTATE])
1010 		set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
1011 	if (tb[IFLA_LINKMODE])
1012 		dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
1013 
1014 	return dev;
1015 
1016 err_free:
1017 	free_netdev(dev);
1018 err:
1019 	return ERR_PTR(err);
1020 }
1021 
1022 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
1023 {
1024 	struct net *net = skb->sk->sk_net;
1025 	const struct rtnl_link_ops *ops;
1026 	struct net_device *dev;
1027 	struct ifinfomsg *ifm;
1028 	char kind[MODULE_NAME_LEN];
1029 	char ifname[IFNAMSIZ];
1030 	struct nlattr *tb[IFLA_MAX+1];
1031 	struct nlattr *linkinfo[IFLA_INFO_MAX+1];
1032 	int err;
1033 
1034 #ifdef CONFIG_KMOD
1035 replay:
1036 #endif
1037 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
1038 	if (err < 0)
1039 		return err;
1040 
1041 	if (tb[IFLA_IFNAME])
1042 		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
1043 	else
1044 		ifname[0] = '\0';
1045 
1046 	ifm = nlmsg_data(nlh);
1047 	if (ifm->ifi_index > 0)
1048 		dev = __dev_get_by_index(net, ifm->ifi_index);
1049 	else if (ifname[0])
1050 		dev = __dev_get_by_name(net, ifname);
1051 	else
1052 		dev = NULL;
1053 
1054 	if (tb[IFLA_LINKINFO]) {
1055 		err = nla_parse_nested(linkinfo, IFLA_INFO_MAX,
1056 				       tb[IFLA_LINKINFO], ifla_info_policy);
1057 		if (err < 0)
1058 			return err;
1059 	} else
1060 		memset(linkinfo, 0, sizeof(linkinfo));
1061 
1062 	if (linkinfo[IFLA_INFO_KIND]) {
1063 		nla_strlcpy(kind, linkinfo[IFLA_INFO_KIND], sizeof(kind));
1064 		ops = rtnl_link_ops_get(kind);
1065 	} else {
1066 		kind[0] = '\0';
1067 		ops = NULL;
1068 	}
1069 
1070 	if (1) {
1071 		struct nlattr *attr[ops ? ops->maxtype + 1 : 0], **data = NULL;
1072 
1073 		if (ops) {
1074 			if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) {
1075 				err = nla_parse_nested(attr, ops->maxtype,
1076 						       linkinfo[IFLA_INFO_DATA],
1077 						       ops->policy);
1078 				if (err < 0)
1079 					return err;
1080 				data = attr;
1081 			}
1082 			if (ops->validate) {
1083 				err = ops->validate(tb, data);
1084 				if (err < 0)
1085 					return err;
1086 			}
1087 		}
1088 
1089 		if (dev) {
1090 			int modified = 0;
1091 
1092 			if (nlh->nlmsg_flags & NLM_F_EXCL)
1093 				return -EEXIST;
1094 			if (nlh->nlmsg_flags & NLM_F_REPLACE)
1095 				return -EOPNOTSUPP;
1096 
1097 			if (linkinfo[IFLA_INFO_DATA]) {
1098 				if (!ops || ops != dev->rtnl_link_ops ||
1099 				    !ops->changelink)
1100 					return -EOPNOTSUPP;
1101 
1102 				err = ops->changelink(dev, tb, data);
1103 				if (err < 0)
1104 					return err;
1105 				modified = 1;
1106 			}
1107 
1108 			return do_setlink(dev, ifm, tb, ifname, modified);
1109 		}
1110 
1111 		if (!(nlh->nlmsg_flags & NLM_F_CREATE))
1112 			return -ENODEV;
1113 
1114 		if (ifm->ifi_index || ifm->ifi_flags || ifm->ifi_change)
1115 			return -EOPNOTSUPP;
1116 		if (tb[IFLA_MAP] || tb[IFLA_MASTER] || tb[IFLA_PROTINFO])
1117 			return -EOPNOTSUPP;
1118 
1119 		if (!ops) {
1120 #ifdef CONFIG_KMOD
1121 			if (kind[0]) {
1122 				__rtnl_unlock();
1123 				request_module("rtnl-link-%s", kind);
1124 				rtnl_lock();
1125 				ops = rtnl_link_ops_get(kind);
1126 				if (ops)
1127 					goto replay;
1128 			}
1129 #endif
1130 			return -EOPNOTSUPP;
1131 		}
1132 
1133 		if (!ifname[0])
1134 			snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
1135 
1136 		dev = rtnl_create_link(net, ifname, ops, tb);
1137 
1138 		if (IS_ERR(dev))
1139 			err = PTR_ERR(dev);
1140 		else if (ops->newlink)
1141 			err = ops->newlink(dev, tb, data);
1142 		else
1143 			err = register_netdevice(dev);
1144 
1145 		if (err < 0 && !IS_ERR(dev))
1146 			free_netdev(dev);
1147 		return err;
1148 	}
1149 }
1150 
1151 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
1152 {
1153 	struct net *net = skb->sk->sk_net;
1154 	struct ifinfomsg *ifm;
1155 	struct nlattr *tb[IFLA_MAX+1];
1156 	struct net_device *dev = NULL;
1157 	struct sk_buff *nskb;
1158 	int err;
1159 
1160 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
1161 	if (err < 0)
1162 		return err;
1163 
1164 	ifm = nlmsg_data(nlh);
1165 	if (ifm->ifi_index > 0) {
1166 		dev = dev_get_by_index(net, ifm->ifi_index);
1167 		if (dev == NULL)
1168 			return -ENODEV;
1169 	} else
1170 		return -EINVAL;
1171 
1172 	nskb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
1173 	if (nskb == NULL) {
1174 		err = -ENOBUFS;
1175 		goto errout;
1176 	}
1177 
1178 	err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).pid,
1179 			       nlh->nlmsg_seq, 0, 0);
1180 	if (err < 0) {
1181 		/* -EMSGSIZE implies BUG in if_nlmsg_size */
1182 		WARN_ON(err == -EMSGSIZE);
1183 		kfree_skb(nskb);
1184 		goto errout;
1185 	}
1186 	err = rtnl_unicast(nskb, NETLINK_CB(skb).pid);
1187 errout:
1188 	dev_put(dev);
1189 
1190 	return err;
1191 }
1192 
1193 static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
1194 {
1195 	int idx;
1196 	int s_idx = cb->family;
1197 
1198 	if (s_idx == 0)
1199 		s_idx = 1;
1200 	for (idx=1; idx<NPROTO; idx++) {
1201 		int type = cb->nlh->nlmsg_type-RTM_BASE;
1202 		if (idx < s_idx || idx == PF_PACKET)
1203 			continue;
1204 		if (rtnl_msg_handlers[idx] == NULL ||
1205 		    rtnl_msg_handlers[idx][type].dumpit == NULL)
1206 			continue;
1207 		if (idx > s_idx)
1208 			memset(&cb->args[0], 0, sizeof(cb->args));
1209 		if (rtnl_msg_handlers[idx][type].dumpit(skb, cb))
1210 			break;
1211 	}
1212 	cb->family = idx;
1213 
1214 	return skb->len;
1215 }
1216 
1217 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
1218 {
1219 	struct sk_buff *skb;
1220 	int err = -ENOBUFS;
1221 
1222 	skb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
1223 	if (skb == NULL)
1224 		goto errout;
1225 
1226 	err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0);
1227 	if (err < 0) {
1228 		/* -EMSGSIZE implies BUG in if_nlmsg_size() */
1229 		WARN_ON(err == -EMSGSIZE);
1230 		kfree_skb(skb);
1231 		goto errout;
1232 	}
1233 	err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
1234 errout:
1235 	if (err < 0)
1236 		rtnl_set_sk_err(RTNLGRP_LINK, err);
1237 }
1238 
1239 /* Protected by RTNL sempahore.  */
1240 static struct rtattr **rta_buf;
1241 static int rtattr_max;
1242 
1243 /* Process one rtnetlink message. */
1244 
1245 static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1246 {
1247 	rtnl_doit_func doit;
1248 	int sz_idx, kind;
1249 	int min_len;
1250 	int family;
1251 	int type;
1252 	int err;
1253 
1254 	type = nlh->nlmsg_type;
1255 	if (type > RTM_MAX)
1256 		return -EOPNOTSUPP;
1257 
1258 	type -= RTM_BASE;
1259 
1260 	/* All the messages must have at least 1 byte length */
1261 	if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
1262 		return 0;
1263 
1264 	family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
1265 	if (family >= NPROTO)
1266 		return -EAFNOSUPPORT;
1267 
1268 	sz_idx = type>>2;
1269 	kind = type&3;
1270 
1271 	if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN))
1272 		return -EPERM;
1273 
1274 	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
1275 		rtnl_dumpit_func dumpit;
1276 
1277 		dumpit = rtnl_get_dumpit(family, type);
1278 		if (dumpit == NULL)
1279 			return -EOPNOTSUPP;
1280 
1281 		__rtnl_unlock();
1282 		err = netlink_dump_start(rtnl, skb, nlh, dumpit, NULL);
1283 		rtnl_lock();
1284 		return err;
1285 	}
1286 
1287 	memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
1288 
1289 	min_len = rtm_min[sz_idx];
1290 	if (nlh->nlmsg_len < min_len)
1291 		return -EINVAL;
1292 
1293 	if (nlh->nlmsg_len > min_len) {
1294 		int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
1295 		struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
1296 
1297 		while (RTA_OK(attr, attrlen)) {
1298 			unsigned flavor = attr->rta_type;
1299 			if (flavor) {
1300 				if (flavor > rta_max[sz_idx])
1301 					return -EINVAL;
1302 				rta_buf[flavor-1] = attr;
1303 			}
1304 			attr = RTA_NEXT(attr, attrlen);
1305 		}
1306 	}
1307 
1308 	doit = rtnl_get_doit(family, type);
1309 	if (doit == NULL)
1310 		return -EOPNOTSUPP;
1311 
1312 	return doit(skb, nlh, (void *)&rta_buf[0]);
1313 }
1314 
1315 static void rtnetlink_rcv(struct sk_buff *skb)
1316 {
1317 	rtnl_lock();
1318 	netlink_rcv_skb(skb, &rtnetlink_rcv_msg);
1319 	rtnl_unlock();
1320 }
1321 
1322 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
1323 {
1324 	struct net_device *dev = ptr;
1325 
1326 	if (dev->nd_net != &init_net)
1327 		return NOTIFY_DONE;
1328 
1329 	switch (event) {
1330 	case NETDEV_UNREGISTER:
1331 		rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
1332 		break;
1333 	case NETDEV_REGISTER:
1334 		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
1335 		break;
1336 	case NETDEV_UP:
1337 	case NETDEV_DOWN:
1338 		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1339 		break;
1340 	case NETDEV_CHANGE:
1341 	case NETDEV_GOING_DOWN:
1342 		break;
1343 	default:
1344 		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
1345 		break;
1346 	}
1347 	return NOTIFY_DONE;
1348 }
1349 
1350 static struct notifier_block rtnetlink_dev_notifier = {
1351 	.notifier_call	= rtnetlink_event,
1352 };
1353 
1354 void __init rtnetlink_init(void)
1355 {
1356 	int i;
1357 
1358 	rtattr_max = 0;
1359 	for (i = 0; i < ARRAY_SIZE(rta_max); i++)
1360 		if (rta_max[i] > rtattr_max)
1361 			rtattr_max = rta_max[i];
1362 	rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
1363 	if (!rta_buf)
1364 		panic("rtnetlink_init: cannot allocate rta_buf\n");
1365 
1366 	rtnl = netlink_kernel_create(&init_net, NETLINK_ROUTE, RTNLGRP_MAX,
1367 				     rtnetlink_rcv, &rtnl_mutex, THIS_MODULE);
1368 	if (rtnl == NULL)
1369 		panic("rtnetlink_init: cannot initialize rtnetlink\n");
1370 	netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
1371 	register_netdevice_notifier(&rtnetlink_dev_notifier);
1372 
1373 	rtnl_register(PF_UNSPEC, RTM_GETLINK, rtnl_getlink, rtnl_dump_ifinfo);
1374 	rtnl_register(PF_UNSPEC, RTM_SETLINK, rtnl_setlink, NULL);
1375 	rtnl_register(PF_UNSPEC, RTM_NEWLINK, rtnl_newlink, NULL);
1376 	rtnl_register(PF_UNSPEC, RTM_DELLINK, rtnl_dellink, NULL);
1377 
1378 	rtnl_register(PF_UNSPEC, RTM_GETADDR, NULL, rtnl_dump_all);
1379 	rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all);
1380 }
1381 
1382 EXPORT_SYMBOL(__rta_fill);
1383 EXPORT_SYMBOL(rtattr_strlcpy);
1384 EXPORT_SYMBOL(rtattr_parse);
1385 EXPORT_SYMBOL(__rtattr_parse_nested_compat);
1386 EXPORT_SYMBOL(rtnetlink_put_metrics);
1387 EXPORT_SYMBOL(rtnl_lock);
1388 EXPORT_SYMBOL(rtnl_trylock);
1389 EXPORT_SYMBOL(rtnl_unlock);
1390 EXPORT_SYMBOL(rtnl_unicast);
1391 EXPORT_SYMBOL(rtnl_notify);
1392 EXPORT_SYMBOL(rtnl_set_sk_err);
1393 EXPORT_SYMBOL(rtnl_create_link);
1394 EXPORT_SYMBOL(ifla_policy);
1395