xref: /openbmc/linux/net/core/rtnetlink.c (revision 87c2ce3b)
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/config.h>
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/socket.h>
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/timer.h>
27 #include <linux/string.h>
28 #include <linux/sockios.h>
29 #include <linux/net.h>
30 #include <linux/fcntl.h>
31 #include <linux/mm.h>
32 #include <linux/slab.h>
33 #include <linux/interrupt.h>
34 #include <linux/capability.h>
35 #include <linux/skbuff.h>
36 #include <linux/init.h>
37 #include <linux/security.h>
38 
39 #include <asm/uaccess.h>
40 #include <asm/system.h>
41 #include <asm/string.h>
42 
43 #include <linux/inet.h>
44 #include <linux/netdevice.h>
45 #include <net/ip.h>
46 #include <net/protocol.h>
47 #include <net/arp.h>
48 #include <net/route.h>
49 #include <net/udp.h>
50 #include <net/sock.h>
51 #include <net/pkt_sched.h>
52 #include <net/netlink.h>
53 
54 DECLARE_MUTEX(rtnl_sem);
55 
56 void rtnl_lock(void)
57 {
58 	rtnl_shlock();
59 }
60 
61 int rtnl_lock_interruptible(void)
62 {
63 	return down_interruptible(&rtnl_sem);
64 }
65 
66 void rtnl_unlock(void)
67 {
68 	rtnl_shunlock();
69 
70 	netdev_run_todo();
71 }
72 
73 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
74 {
75 	memset(tb, 0, sizeof(struct rtattr*)*maxattr);
76 
77 	while (RTA_OK(rta, len)) {
78 		unsigned flavor = rta->rta_type;
79 		if (flavor && flavor <= maxattr)
80 			tb[flavor-1] = rta;
81 		rta = RTA_NEXT(rta, len);
82 	}
83 	return 0;
84 }
85 
86 struct sock *rtnl;
87 
88 struct rtnetlink_link * rtnetlink_links[NPROTO];
89 
90 static const int rtm_min[RTM_NR_FAMILIES] =
91 {
92 	[RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
93 	[RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
94 	[RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
95 	[RTM_FAM(RTM_NEWNEIGH)]     = NLMSG_LENGTH(sizeof(struct ndmsg)),
96 	[RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct rtmsg)),
97 	[RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
98 	[RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
99 	[RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
100 	[RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
101 	[RTM_FAM(RTM_NEWPREFIX)]    = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
102 	[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
103 	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
104 	[RTM_FAM(RTM_NEWNEIGHTBL)]  = NLMSG_LENGTH(sizeof(struct ndtmsg)),
105 };
106 
107 static const int rta_max[RTM_NR_FAMILIES] =
108 {
109 	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
110 	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
111 	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
112 	[RTM_FAM(RTM_NEWNEIGH)]     = NDA_MAX,
113 	[RTM_FAM(RTM_NEWRULE)]      = RTA_MAX,
114 	[RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
115 	[RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
116 	[RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
117 	[RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
118 	[RTM_FAM(RTM_NEWNEIGHTBL)]  = NDTA_MAX,
119 };
120 
121 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
122 {
123 	struct rtattr *rta;
124 	int size = RTA_LENGTH(attrlen);
125 
126 	rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
127 	rta->rta_type = attrtype;
128 	rta->rta_len = size;
129 	memcpy(RTA_DATA(rta), data, attrlen);
130 	memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
131 }
132 
133 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
134 {
135 	size_t ret = RTA_PAYLOAD(rta);
136 	char *src = RTA_DATA(rta);
137 
138 	if (ret > 0 && src[ret - 1] == '\0')
139 		ret--;
140 	if (size > 0) {
141 		size_t len = (ret >= size) ? size - 1 : ret;
142 		memset(dest, 0, size);
143 		memcpy(dest, src, len);
144 	}
145 	return ret;
146 }
147 
148 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
149 {
150 	int err = 0;
151 
152 	NETLINK_CB(skb).dst_group = group;
153 	if (echo)
154 		atomic_inc(&skb->users);
155 	netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
156 	if (echo)
157 		err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
158 	return err;
159 }
160 
161 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
162 {
163 	struct rtattr *mx = (struct rtattr*)skb->tail;
164 	int i;
165 
166 	RTA_PUT(skb, RTA_METRICS, 0, NULL);
167 	for (i=0; i<RTAX_MAX; i++) {
168 		if (metrics[i])
169 			RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
170 	}
171 	mx->rta_len = skb->tail - (u8*)mx;
172 	if (mx->rta_len == RTA_LENGTH(0))
173 		skb_trim(skb, (u8*)mx - skb->data);
174 	return 0;
175 
176 rtattr_failure:
177 	skb_trim(skb, (u8*)mx - skb->data);
178 	return -1;
179 }
180 
181 
182 static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
183 				 int type, u32 pid, u32 seq, u32 change,
184 				 unsigned int flags)
185 {
186 	struct ifinfomsg *r;
187 	struct nlmsghdr  *nlh;
188 	unsigned char	 *b = skb->tail;
189 
190 	nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*r), flags);
191 	r = NLMSG_DATA(nlh);
192 	r->ifi_family = AF_UNSPEC;
193 	r->__ifi_pad = 0;
194 	r->ifi_type = dev->type;
195 	r->ifi_index = dev->ifindex;
196 	r->ifi_flags = dev_get_flags(dev);
197 	r->ifi_change = change;
198 
199 	RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name);
200 
201 	if (1) {
202 		u32 txqlen = dev->tx_queue_len;
203 		RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen);
204 	}
205 
206 	if (1) {
207 		u32 weight = dev->weight;
208 		RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight);
209 	}
210 
211 	if (1) {
212 		struct rtnl_link_ifmap map = {
213 			.mem_start   = dev->mem_start,
214 			.mem_end     = dev->mem_end,
215 			.base_addr   = dev->base_addr,
216 			.irq         = dev->irq,
217 			.dma         = dev->dma,
218 			.port        = dev->if_port,
219 		};
220 		RTA_PUT(skb, IFLA_MAP, sizeof(map), &map);
221 	}
222 
223 	if (dev->addr_len) {
224 		RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
225 		RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
226 	}
227 
228 	if (1) {
229 		u32 mtu = dev->mtu;
230 		RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu);
231 	}
232 
233 	if (dev->ifindex != dev->iflink) {
234 		u32 iflink = dev->iflink;
235 		RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink);
236 	}
237 
238 	if (dev->qdisc_sleeping)
239 		RTA_PUT(skb, IFLA_QDISC,
240 			strlen(dev->qdisc_sleeping->ops->id) + 1,
241 			dev->qdisc_sleeping->ops->id);
242 
243 	if (dev->master) {
244 		u32 master = dev->master->ifindex;
245 		RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master);
246 	}
247 
248 	if (dev->get_stats) {
249 		unsigned long *stats = (unsigned long*)dev->get_stats(dev);
250 		if (stats) {
251 			struct rtattr  *a;
252 			__u32	       *s;
253 			int		i;
254 			int		n = sizeof(struct rtnl_link_stats)/4;
255 
256 			a = __RTA_PUT(skb, IFLA_STATS, n*4);
257 			s = RTA_DATA(a);
258 			for (i=0; i<n; i++)
259 				s[i] = stats[i];
260 		}
261 	}
262 	nlh->nlmsg_len = skb->tail - b;
263 	return skb->len;
264 
265 nlmsg_failure:
266 rtattr_failure:
267 	skb_trim(skb, b - skb->data);
268 	return -1;
269 }
270 
271 static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
272 {
273 	int idx;
274 	int s_idx = cb->args[0];
275 	struct net_device *dev;
276 
277 	read_lock(&dev_base_lock);
278 	for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
279 		if (idx < s_idx)
280 			continue;
281 		if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK,
282 					  NETLINK_CB(cb->skb).pid,
283 					  cb->nlh->nlmsg_seq, 0,
284 					  NLM_F_MULTI) <= 0)
285 			break;
286 	}
287 	read_unlock(&dev_base_lock);
288 	cb->args[0] = idx;
289 
290 	return skb->len;
291 }
292 
293 static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
294 {
295 	struct ifinfomsg  *ifm = NLMSG_DATA(nlh);
296 	struct rtattr    **ida = arg;
297 	struct net_device *dev;
298 	int err, send_addr_notify = 0;
299 
300 	if (ifm->ifi_index >= 0)
301 		dev = dev_get_by_index(ifm->ifi_index);
302 	else if (ida[IFLA_IFNAME - 1]) {
303 		char ifname[IFNAMSIZ];
304 
305 		if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
306 		                   IFNAMSIZ) >= IFNAMSIZ)
307 			return -EINVAL;
308 		dev = dev_get_by_name(ifname);
309 	} else
310 		return -EINVAL;
311 
312 	if (!dev)
313 		return -ENODEV;
314 
315 	err = -EINVAL;
316 
317 	if (ifm->ifi_flags)
318 		dev_change_flags(dev, ifm->ifi_flags);
319 
320 	if (ida[IFLA_MAP - 1]) {
321 		struct rtnl_link_ifmap *u_map;
322 		struct ifmap k_map;
323 
324 		if (!dev->set_config) {
325 			err = -EOPNOTSUPP;
326 			goto out;
327 		}
328 
329 		if (!netif_device_present(dev)) {
330 			err = -ENODEV;
331 			goto out;
332 		}
333 
334 		if (ida[IFLA_MAP - 1]->rta_len != RTA_LENGTH(sizeof(*u_map)))
335 			goto out;
336 
337 		u_map = RTA_DATA(ida[IFLA_MAP - 1]);
338 
339 		k_map.mem_start = (unsigned long) u_map->mem_start;
340 		k_map.mem_end = (unsigned long) u_map->mem_end;
341 		k_map.base_addr = (unsigned short) u_map->base_addr;
342 		k_map.irq = (unsigned char) u_map->irq;
343 		k_map.dma = (unsigned char) u_map->dma;
344 		k_map.port = (unsigned char) u_map->port;
345 
346 		err = dev->set_config(dev, &k_map);
347 
348 		if (err)
349 			goto out;
350 	}
351 
352 	if (ida[IFLA_ADDRESS - 1]) {
353 		if (!dev->set_mac_address) {
354 			err = -EOPNOTSUPP;
355 			goto out;
356 		}
357 		if (!netif_device_present(dev)) {
358 			err = -ENODEV;
359 			goto out;
360 		}
361 		if (ida[IFLA_ADDRESS - 1]->rta_len != RTA_LENGTH(dev->addr_len))
362 			goto out;
363 
364 		err = dev->set_mac_address(dev, RTA_DATA(ida[IFLA_ADDRESS - 1]));
365 		if (err)
366 			goto out;
367 		send_addr_notify = 1;
368 	}
369 
370 	if (ida[IFLA_BROADCAST - 1]) {
371 		if (ida[IFLA_BROADCAST - 1]->rta_len != RTA_LENGTH(dev->addr_len))
372 			goto out;
373 		memcpy(dev->broadcast, RTA_DATA(ida[IFLA_BROADCAST - 1]),
374 		       dev->addr_len);
375 		send_addr_notify = 1;
376 	}
377 
378 	if (ida[IFLA_MTU - 1]) {
379 		if (ida[IFLA_MTU - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
380 			goto out;
381 		err = dev_set_mtu(dev, *((u32 *) RTA_DATA(ida[IFLA_MTU - 1])));
382 
383 		if (err)
384 			goto out;
385 
386 	}
387 
388 	if (ida[IFLA_TXQLEN - 1]) {
389 		if (ida[IFLA_TXQLEN - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
390 			goto out;
391 
392 		dev->tx_queue_len = *((u32 *) RTA_DATA(ida[IFLA_TXQLEN - 1]));
393 	}
394 
395 	if (ida[IFLA_WEIGHT - 1]) {
396 		if (ida[IFLA_WEIGHT - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
397 			goto out;
398 
399 		dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1]));
400 	}
401 
402 	if (ifm->ifi_index >= 0 && ida[IFLA_IFNAME - 1]) {
403 		char ifname[IFNAMSIZ];
404 
405 		if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
406 		                   IFNAMSIZ) >= IFNAMSIZ)
407 			goto out;
408 		err = dev_change_name(dev, ifname);
409 		if (err)
410 			goto out;
411 	}
412 
413 	err = 0;
414 
415 out:
416 	if (send_addr_notify)
417 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
418 
419 	dev_put(dev);
420 	return err;
421 }
422 
423 static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
424 {
425 	int idx;
426 	int s_idx = cb->family;
427 
428 	if (s_idx == 0)
429 		s_idx = 1;
430 	for (idx=1; idx<NPROTO; idx++) {
431 		int type = cb->nlh->nlmsg_type-RTM_BASE;
432 		if (idx < s_idx || idx == PF_PACKET)
433 			continue;
434 		if (rtnetlink_links[idx] == NULL ||
435 		    rtnetlink_links[idx][type].dumpit == NULL)
436 			continue;
437 		if (idx > s_idx)
438 			memset(&cb->args[0], 0, sizeof(cb->args));
439 		if (rtnetlink_links[idx][type].dumpit(skb, cb))
440 			break;
441 	}
442 	cb->family = idx;
443 
444 	return skb->len;
445 }
446 
447 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
448 {
449 	struct sk_buff *skb;
450 	int size = NLMSG_SPACE(sizeof(struct ifinfomsg) +
451 			       sizeof(struct rtnl_link_ifmap) +
452 			       sizeof(struct rtnl_link_stats) + 128);
453 
454 	skb = alloc_skb(size, GFP_KERNEL);
455 	if (!skb)
456 		return;
457 
458 	if (rtnetlink_fill_ifinfo(skb, dev, type, current->pid, 0, change, 0) < 0) {
459 		kfree_skb(skb);
460 		return;
461 	}
462 	NETLINK_CB(skb).dst_group = RTNLGRP_LINK;
463 	netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL);
464 }
465 
466 /* Protected by RTNL sempahore.  */
467 static struct rtattr **rta_buf;
468 static int rtattr_max;
469 
470 /* Process one rtnetlink message. */
471 
472 static __inline__ int
473 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
474 {
475 	struct rtnetlink_link *link;
476 	struct rtnetlink_link *link_tab;
477 	int sz_idx, kind;
478 	int min_len;
479 	int family;
480 	int type;
481 	int err;
482 
483 	/* Only requests are handled by kernel now */
484 	if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
485 		return 0;
486 
487 	type = nlh->nlmsg_type;
488 
489 	/* A control message: ignore them */
490 	if (type < RTM_BASE)
491 		return 0;
492 
493 	/* Unknown message: reply with EINVAL */
494 	if (type > RTM_MAX)
495 		goto err_inval;
496 
497 	type -= RTM_BASE;
498 
499 	/* All the messages must have at least 1 byte length */
500 	if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
501 		return 0;
502 
503 	family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
504 	if (family >= NPROTO) {
505 		*errp = -EAFNOSUPPORT;
506 		return -1;
507 	}
508 
509 	link_tab = rtnetlink_links[family];
510 	if (link_tab == NULL)
511 		link_tab = rtnetlink_links[PF_UNSPEC];
512 	link = &link_tab[type];
513 
514 	sz_idx = type>>2;
515 	kind = type&3;
516 
517 	if (kind != 2 && security_netlink_recv(skb)) {
518 		*errp = -EPERM;
519 		return -1;
520 	}
521 
522 	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
523 		if (link->dumpit == NULL)
524 			link = &(rtnetlink_links[PF_UNSPEC][type]);
525 
526 		if (link->dumpit == NULL)
527 			goto err_inval;
528 
529 		if ((*errp = netlink_dump_start(rtnl, skb, nlh,
530 						link->dumpit, NULL)) != 0) {
531 			return -1;
532 		}
533 
534 		netlink_queue_skip(nlh, skb);
535 		return -1;
536 	}
537 
538 	memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
539 
540 	min_len = rtm_min[sz_idx];
541 	if (nlh->nlmsg_len < min_len)
542 		goto err_inval;
543 
544 	if (nlh->nlmsg_len > min_len) {
545 		int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
546 		struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
547 
548 		while (RTA_OK(attr, attrlen)) {
549 			unsigned flavor = attr->rta_type;
550 			if (flavor) {
551 				if (flavor > rta_max[sz_idx])
552 					goto err_inval;
553 				rta_buf[flavor-1] = attr;
554 			}
555 			attr = RTA_NEXT(attr, attrlen);
556 		}
557 	}
558 
559 	if (link->doit == NULL)
560 		link = &(rtnetlink_links[PF_UNSPEC][type]);
561 	if (link->doit == NULL)
562 		goto err_inval;
563 	err = link->doit(skb, nlh, (void *)&rta_buf[0]);
564 
565 	*errp = err;
566 	return err;
567 
568 err_inval:
569 	*errp = -EINVAL;
570 	return -1;
571 }
572 
573 static void rtnetlink_rcv(struct sock *sk, int len)
574 {
575 	unsigned int qlen = 0;
576 
577 	do {
578 		rtnl_lock();
579 		netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
580 		up(&rtnl_sem);
581 
582 		netdev_run_todo();
583 	} while (qlen);
584 }
585 
586 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
587 {
588 	[RTM_GETLINK     - RTM_BASE] = { .dumpit = rtnetlink_dump_ifinfo },
589 	[RTM_SETLINK     - RTM_BASE] = { .doit   = do_setlink		 },
590 	[RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnetlink_dump_all	 },
591 	[RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnetlink_dump_all	 },
592 	[RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add		 },
593 	[RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete		 },
594 	[RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info	 },
595 	[RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnetlink_dump_all	 },
596 	[RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info	 },
597 	[RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set		 },
598 };
599 
600 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
601 {
602 	struct net_device *dev = ptr;
603 	switch (event) {
604 	case NETDEV_UNREGISTER:
605 		rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
606 		break;
607 	case NETDEV_REGISTER:
608 		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
609 		break;
610 	case NETDEV_UP:
611 	case NETDEV_DOWN:
612 		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
613 		break;
614 	case NETDEV_CHANGE:
615 	case NETDEV_GOING_DOWN:
616 		break;
617 	default:
618 		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
619 		break;
620 	}
621 	return NOTIFY_DONE;
622 }
623 
624 static struct notifier_block rtnetlink_dev_notifier = {
625 	.notifier_call	= rtnetlink_event,
626 };
627 
628 void __init rtnetlink_init(void)
629 {
630 	int i;
631 
632 	rtattr_max = 0;
633 	for (i = 0; i < ARRAY_SIZE(rta_max); i++)
634 		if (rta_max[i] > rtattr_max)
635 			rtattr_max = rta_max[i];
636 	rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
637 	if (!rta_buf)
638 		panic("rtnetlink_init: cannot allocate rta_buf\n");
639 
640 	rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
641 	                             THIS_MODULE);
642 	if (rtnl == NULL)
643 		panic("rtnetlink_init: cannot initialize rtnetlink\n");
644 	netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
645 	register_netdevice_notifier(&rtnetlink_dev_notifier);
646 	rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
647 	rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
648 }
649 
650 EXPORT_SYMBOL(__rta_fill);
651 EXPORT_SYMBOL(rtattr_strlcpy);
652 EXPORT_SYMBOL(rtattr_parse);
653 EXPORT_SYMBOL(rtnetlink_links);
654 EXPORT_SYMBOL(rtnetlink_put_metrics);
655 EXPORT_SYMBOL(rtnl);
656 EXPORT_SYMBOL(rtnl_lock);
657 EXPORT_SYMBOL(rtnl_lock_interruptible);
658 EXPORT_SYMBOL(rtnl_sem);
659 EXPORT_SYMBOL(rtnl_unlock);
660