[PATCH] kill gratitious includes of major.h under net/*
[linux-2.6] / net / core / rtnetlink.c
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
53 DECLARE_MUTEX(rtnl_sem);
54
55 void rtnl_lock(void)
56 {
57         rtnl_shlock();
58 }
59
60 int rtnl_lock_interruptible(void)
61 {
62         return down_interruptible(&rtnl_sem);
63 }
64  
65 void rtnl_unlock(void)
66 {
67         rtnl_shunlock();
68
69         netdev_run_todo();
70 }
71
72 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
73 {
74         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
75
76         while (RTA_OK(rta, len)) {
77                 unsigned flavor = rta->rta_type;
78                 if (flavor && flavor <= maxattr)
79                         tb[flavor-1] = rta;
80                 rta = RTA_NEXT(rta, len);
81         }
82         return 0;
83 }
84
85 struct sock *rtnl;
86
87 struct rtnetlink_link * rtnetlink_links[NPROTO];
88
89 static const int rtm_min[(RTM_MAX+1-RTM_BASE)/4] =
90 {
91         NLMSG_LENGTH(sizeof(struct ifinfomsg)),
92         NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
93         NLMSG_LENGTH(sizeof(struct rtmsg)),
94         NLMSG_LENGTH(sizeof(struct ndmsg)),
95         NLMSG_LENGTH(sizeof(struct rtmsg)),
96         NLMSG_LENGTH(sizeof(struct tcmsg)),
97         NLMSG_LENGTH(sizeof(struct tcmsg)),
98         NLMSG_LENGTH(sizeof(struct tcmsg)),
99         NLMSG_LENGTH(sizeof(struct tcamsg))
100 };
101
102 static const int rta_max[(RTM_MAX+1-RTM_BASE)/4] =
103 {
104         IFLA_MAX,
105         IFA_MAX,
106         RTA_MAX,
107         NDA_MAX,
108         RTA_MAX,
109         TCA_MAX,
110         TCA_MAX,
111         TCA_MAX,
112         TCAA_MAX
113 };
114
115 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
116 {
117         struct rtattr *rta;
118         int size = RTA_LENGTH(attrlen);
119
120         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
121         rta->rta_type = attrtype;
122         rta->rta_len = size;
123         memcpy(RTA_DATA(rta), data, attrlen);
124 }
125
126 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
127 {
128         size_t ret = RTA_PAYLOAD(rta);
129         char *src = RTA_DATA(rta);
130
131         if (ret > 0 && src[ret - 1] == '\0')
132                 ret--;
133         if (size > 0) {
134                 size_t len = (ret >= size) ? size - 1 : ret;
135                 memset(dest, 0, size);
136                 memcpy(dest, src, len);
137         }
138         return ret;
139 }
140
141 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
142 {
143         int err = 0;
144
145         NETLINK_CB(skb).dst_groups = group;
146         if (echo)
147                 atomic_inc(&skb->users);
148         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
149         if (echo)
150                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
151         return err;
152 }
153
154 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
155 {
156         struct rtattr *mx = (struct rtattr*)skb->tail;
157         int i;
158
159         RTA_PUT(skb, RTA_METRICS, 0, NULL);
160         for (i=0; i<RTAX_MAX; i++) {
161                 if (metrics[i])
162                         RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
163         }
164         mx->rta_len = skb->tail - (u8*)mx;
165         if (mx->rta_len == RTA_LENGTH(0))
166                 skb_trim(skb, (u8*)mx - skb->data);
167         return 0;
168
169 rtattr_failure:
170         skb_trim(skb, (u8*)mx - skb->data);
171         return -1;
172 }
173
174
175 static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
176                                  int type, u32 pid, u32 seq, u32 change)
177 {
178         struct ifinfomsg *r;
179         struct nlmsghdr  *nlh;
180         unsigned char    *b = skb->tail;
181
182         nlh = NLMSG_PUT(skb, pid, seq, type, sizeof(*r));
183         if (pid) nlh->nlmsg_flags |= NLM_F_MULTI;
184         r = NLMSG_DATA(nlh);
185         r->ifi_family = AF_UNSPEC;
186         r->ifi_type = dev->type;
187         r->ifi_index = dev->ifindex;
188         r->ifi_flags = dev_get_flags(dev);
189         r->ifi_change = change;
190
191         RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name);
192
193         if (1) {
194                 u32 txqlen = dev->tx_queue_len;
195                 RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen);
196         }
197
198         if (1) {
199                 u32 weight = dev->weight;
200                 RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight);
201         }
202
203         if (1) {
204                 struct rtnl_link_ifmap map = {
205                         .mem_start   = dev->mem_start,
206                         .mem_end     = dev->mem_end,
207                         .base_addr   = dev->base_addr,
208                         .irq         = dev->irq,
209                         .dma         = dev->dma,
210                         .port        = dev->if_port,
211                 };
212                 RTA_PUT(skb, IFLA_MAP, sizeof(map), &map);
213         }
214
215         if (dev->addr_len) {
216                 RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
217                 RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
218         }
219
220         if (1) {
221                 u32 mtu = dev->mtu;
222                 RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu);
223         }
224
225         if (dev->ifindex != dev->iflink) {
226                 u32 iflink = dev->iflink;
227                 RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink);
228         }
229
230         if (dev->qdisc_sleeping)
231                 RTA_PUT(skb, IFLA_QDISC,
232                         strlen(dev->qdisc_sleeping->ops->id) + 1,
233                         dev->qdisc_sleeping->ops->id);
234         
235         if (dev->master) {
236                 u32 master = dev->master->ifindex;
237                 RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master);
238         }
239
240         if (dev->get_stats) {
241                 unsigned long *stats = (unsigned long*)dev->get_stats(dev);
242                 if (stats) {
243                         struct rtattr  *a;
244                         __u32          *s;
245                         int             i;
246                         int             n = sizeof(struct rtnl_link_stats)/4;
247
248                         a = __RTA_PUT(skb, IFLA_STATS, n*4);
249                         s = RTA_DATA(a);
250                         for (i=0; i<n; i++)
251                                 s[i] = stats[i];
252                 }
253         }
254         nlh->nlmsg_len = skb->tail - b;
255         return skb->len;
256
257 nlmsg_failure:
258 rtattr_failure:
259         skb_trim(skb, b - skb->data);
260         return -1;
261 }
262
263 static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
264 {
265         int idx;
266         int s_idx = cb->args[0];
267         struct net_device *dev;
268
269         read_lock(&dev_base_lock);
270         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
271                 if (idx < s_idx)
272                         continue;
273                 if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, 0) <= 0)
274                         break;
275         }
276         read_unlock(&dev_base_lock);
277         cb->args[0] = idx;
278
279         return skb->len;
280 }
281
282 static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
283 {
284         struct ifinfomsg  *ifm = NLMSG_DATA(nlh);
285         struct rtattr    **ida = arg;
286         struct net_device *dev;
287         int err, send_addr_notify = 0;
288
289         if (ifm->ifi_index >= 0)
290                 dev = dev_get_by_index(ifm->ifi_index);
291         else if (ida[IFLA_IFNAME - 1]) {
292                 char ifname[IFNAMSIZ];
293
294                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
295                                    IFNAMSIZ) >= IFNAMSIZ)
296                         return -EINVAL;
297                 dev = dev_get_by_name(ifname);
298         } else
299                 return -EINVAL;
300
301         if (!dev)
302                 return -ENODEV;
303
304         err = -EINVAL;
305
306         if (ifm->ifi_flags)
307                 dev_change_flags(dev, ifm->ifi_flags);
308
309         if (ida[IFLA_MAP - 1]) {
310                 struct rtnl_link_ifmap *u_map;
311                 struct ifmap k_map;
312
313                 if (!dev->set_config) {
314                         err = -EOPNOTSUPP;
315                         goto out;
316                 }
317
318                 if (!netif_device_present(dev)) {
319                         err = -ENODEV;
320                         goto out;
321                 }
322                 
323                 if (ida[IFLA_MAP - 1]->rta_len != RTA_LENGTH(sizeof(*u_map)))
324                         goto out;
325
326                 u_map = RTA_DATA(ida[IFLA_MAP - 1]);
327
328                 k_map.mem_start = (unsigned long) u_map->mem_start;
329                 k_map.mem_end = (unsigned long) u_map->mem_end;
330                 k_map.base_addr = (unsigned short) u_map->base_addr;
331                 k_map.irq = (unsigned char) u_map->irq;
332                 k_map.dma = (unsigned char) u_map->dma;
333                 k_map.port = (unsigned char) u_map->port;
334
335                 err = dev->set_config(dev, &k_map);
336
337                 if (err)
338                         goto out;
339         }
340
341         if (ida[IFLA_ADDRESS - 1]) {
342                 if (!dev->set_mac_address) {
343                         err = -EOPNOTSUPP;
344                         goto out;
345                 }
346                 if (!netif_device_present(dev)) {
347                         err = -ENODEV;
348                         goto out;
349                 }
350                 if (ida[IFLA_ADDRESS - 1]->rta_len != RTA_LENGTH(dev->addr_len))
351                         goto out;
352
353                 err = dev->set_mac_address(dev, RTA_DATA(ida[IFLA_ADDRESS - 1]));
354                 if (err)
355                         goto out;
356                 send_addr_notify = 1;
357         }
358
359         if (ida[IFLA_BROADCAST - 1]) {
360                 if (ida[IFLA_BROADCAST - 1]->rta_len != RTA_LENGTH(dev->addr_len))
361                         goto out;
362                 memcpy(dev->broadcast, RTA_DATA(ida[IFLA_BROADCAST - 1]),
363                        dev->addr_len);
364                 send_addr_notify = 1;
365         }
366
367         if (ida[IFLA_MTU - 1]) {
368                 if (ida[IFLA_MTU - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
369                         goto out;
370                 err = dev_set_mtu(dev, *((u32 *) RTA_DATA(ida[IFLA_MTU - 1])));
371
372                 if (err)
373                         goto out;
374
375         }
376
377         if (ida[IFLA_TXQLEN - 1]) {
378                 if (ida[IFLA_TXQLEN - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
379                         goto out;
380
381                 dev->tx_queue_len = *((u32 *) RTA_DATA(ida[IFLA_TXQLEN - 1]));
382         }
383
384         if (ida[IFLA_WEIGHT - 1]) {
385                 if (ida[IFLA_WEIGHT - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
386                         goto out;
387
388                 dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1]));
389         }
390
391         if (ifm->ifi_index >= 0 && ida[IFLA_IFNAME - 1]) {
392                 char ifname[IFNAMSIZ];
393
394                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
395                                    IFNAMSIZ) >= IFNAMSIZ)
396                         goto out;
397                 err = dev_change_name(dev, ifname);
398                 if (err)
399                         goto out;
400         }
401
402         err = 0;
403
404 out:
405         if (send_addr_notify)
406                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
407
408         dev_put(dev);
409         return err;
410 }
411
412 static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
413 {
414         int idx;
415         int s_idx = cb->family;
416
417         if (s_idx == 0)
418                 s_idx = 1;
419         for (idx=1; idx<NPROTO; idx++) {
420                 int type = cb->nlh->nlmsg_type-RTM_BASE;
421                 if (idx < s_idx || idx == PF_PACKET)
422                         continue;
423                 if (rtnetlink_links[idx] == NULL ||
424                     rtnetlink_links[idx][type].dumpit == NULL)
425                         continue;
426                 if (idx > s_idx)
427                         memset(&cb->args[0], 0, sizeof(cb->args));
428                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
429                         break;
430         }
431         cb->family = idx;
432
433         return skb->len;
434 }
435
436 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
437 {
438         struct sk_buff *skb;
439         int size = NLMSG_SPACE(sizeof(struct ifinfomsg) +
440                                sizeof(struct rtnl_link_ifmap) +
441                                sizeof(struct rtnl_link_stats) + 128);
442
443         skb = alloc_skb(size, GFP_KERNEL);
444         if (!skb)
445                 return;
446
447         if (rtnetlink_fill_ifinfo(skb, dev, type, 0, 0, change) < 0) {
448                 kfree_skb(skb);
449                 return;
450         }
451         NETLINK_CB(skb).dst_groups = RTMGRP_LINK;
452         netlink_broadcast(rtnl, skb, 0, RTMGRP_LINK, GFP_KERNEL);
453 }
454
455 static int rtnetlink_done(struct netlink_callback *cb)
456 {
457         return 0;
458 }
459
460 /* Protected by RTNL sempahore.  */
461 static struct rtattr **rta_buf;
462 static int rtattr_max;
463
464 /* Process one rtnetlink message. */
465
466 static __inline__ int
467 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
468 {
469         struct rtnetlink_link *link;
470         struct rtnetlink_link *link_tab;
471         int sz_idx, kind;
472         int min_len;
473         int family;
474         int type;
475         int err;
476
477         /* Only requests are handled by kernel now */
478         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
479                 return 0;
480
481         type = nlh->nlmsg_type;
482
483         /* A control message: ignore them */
484         if (type < RTM_BASE)
485                 return 0;
486
487         /* Unknown message: reply with EINVAL */
488         if (type > RTM_MAX)
489                 goto err_inval;
490
491         type -= RTM_BASE;
492
493         /* All the messages must have at least 1 byte length */
494         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
495                 return 0;
496
497         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
498         if (family >= NPROTO) {
499                 *errp = -EAFNOSUPPORT;
500                 return -1;
501         }
502
503         link_tab = rtnetlink_links[family];
504         if (link_tab == NULL)
505                 link_tab = rtnetlink_links[PF_UNSPEC];
506         link = &link_tab[type];
507
508         sz_idx = type>>2;
509         kind = type&3;
510
511         if (kind != 2 && security_netlink_recv(skb)) {
512                 *errp = -EPERM;
513                 return -1;
514         }
515
516         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
517                 u32 rlen;
518
519                 if (link->dumpit == NULL)
520                         link = &(rtnetlink_links[PF_UNSPEC][type]);
521
522                 if (link->dumpit == NULL)
523                         goto err_inval;
524
525                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
526                                                 link->dumpit,
527                                                 rtnetlink_done)) != 0) {
528                         return -1;
529                 }
530                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
531                 if (rlen > skb->len)
532                         rlen = skb->len;
533                 skb_pull(skb, rlen);
534                 return -1;
535         }
536
537         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
538
539         min_len = rtm_min[sz_idx];
540         if (nlh->nlmsg_len < min_len)
541                 goto err_inval;
542
543         if (nlh->nlmsg_len > min_len) {
544                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
545                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
546
547                 while (RTA_OK(attr, attrlen)) {
548                         unsigned flavor = attr->rta_type;
549                         if (flavor) {
550                                 if (flavor > rta_max[sz_idx])
551                                         goto err_inval;
552                                 rta_buf[flavor-1] = attr;
553                         }
554                         attr = RTA_NEXT(attr, attrlen);
555                 }
556         }
557
558         if (link->doit == NULL)
559                 link = &(rtnetlink_links[PF_UNSPEC][type]);
560         if (link->doit == NULL)
561                 goto err_inval;
562         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
563
564         *errp = err;
565         return err;
566
567 err_inval:
568         *errp = -EINVAL;
569         return -1;
570 }
571
572 /* 
573  * Process one packet of messages.
574  * Malformed skbs with wrong lengths of messages are discarded silently.
575  */
576
577 static inline int rtnetlink_rcv_skb(struct sk_buff *skb)
578 {
579         int err;
580         struct nlmsghdr * nlh;
581
582         while (skb->len >= NLMSG_SPACE(0)) {
583                 u32 rlen;
584
585                 nlh = (struct nlmsghdr *)skb->data;
586                 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
587                         return 0;
588                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
589                 if (rlen > skb->len)
590                         rlen = skb->len;
591                 if (rtnetlink_rcv_msg(skb, nlh, &err)) {
592                         /* Not error, but we must interrupt processing here:
593                          *   Note, that in this case we do not pull message
594                          *   from skb, it will be processed later.
595                          */
596                         if (err == 0)
597                                 return -1;
598                         netlink_ack(skb, nlh, err);
599                 } else if (nlh->nlmsg_flags&NLM_F_ACK)
600                         netlink_ack(skb, nlh, 0);
601                 skb_pull(skb, rlen);
602         }
603
604         return 0;
605 }
606
607 /*
608  *  rtnetlink input queue processing routine:
609  *      - try to acquire shared lock. If it is failed, defer processing.
610  *      - feed skbs to rtnetlink_rcv_skb, until it refuse a message,
611  *        that will occur, when a dump started and/or acquisition of
612  *        exclusive lock failed.
613  */
614
615 static void rtnetlink_rcv(struct sock *sk, int len)
616 {
617         do {
618                 struct sk_buff *skb;
619
620                 if (rtnl_shlock_nowait())
621                         return;
622
623                 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
624                         if (rtnetlink_rcv_skb(skb)) {
625                                 if (skb->len)
626                                         skb_queue_head(&sk->sk_receive_queue,
627                                                        skb);
628                                 else
629                                         kfree_skb(skb);
630                                 break;
631                         }
632                         kfree_skb(skb);
633                 }
634
635                 up(&rtnl_sem);
636
637                 netdev_run_todo();
638         } while (rtnl && rtnl->sk_receive_queue.qlen);
639 }
640
641 static struct rtnetlink_link link_rtnetlink_table[RTM_MAX-RTM_BASE+1] =
642 {
643         [RTM_GETLINK  - RTM_BASE] = { .dumpit = rtnetlink_dump_ifinfo },
644         [RTM_SETLINK  - RTM_BASE] = { .doit   = do_setlink            },
645         [RTM_GETADDR  - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
646         [RTM_GETROUTE - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
647         [RTM_NEWNEIGH - RTM_BASE] = { .doit   = neigh_add             },
648         [RTM_DELNEIGH - RTM_BASE] = { .doit   = neigh_delete          },
649         [RTM_GETNEIGH - RTM_BASE] = { .dumpit = neigh_dump_info       },
650         [RTM_GETRULE  - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
651 };
652
653 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
654 {
655         struct net_device *dev = ptr;
656         switch (event) {
657         case NETDEV_UNREGISTER:
658                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
659                 break;
660         case NETDEV_REGISTER:
661                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
662                 break;
663         case NETDEV_UP:
664         case NETDEV_DOWN:
665                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
666                 break;
667         case NETDEV_CHANGE:
668         case NETDEV_GOING_DOWN:
669                 break;
670         default:
671                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
672                 break;
673         }
674         return NOTIFY_DONE;
675 }
676
677 static struct notifier_block rtnetlink_dev_notifier = {
678         .notifier_call  = rtnetlink_event,
679 };
680
681 void __init rtnetlink_init(void)
682 {
683         int i;
684
685         rtattr_max = 0;
686         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
687                 if (rta_max[i] > rtattr_max)
688                         rtattr_max = rta_max[i];
689         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
690         if (!rta_buf)
691                 panic("rtnetlink_init: cannot allocate rta_buf\n");
692
693         rtnl = netlink_kernel_create(NETLINK_ROUTE, rtnetlink_rcv);
694         if (rtnl == NULL)
695                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
696         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
697         register_netdevice_notifier(&rtnetlink_dev_notifier);
698         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
699         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
700 }
701
702 EXPORT_SYMBOL(__rta_fill);
703 EXPORT_SYMBOL(rtattr_strlcpy);
704 EXPORT_SYMBOL(rtattr_parse);
705 EXPORT_SYMBOL(rtnetlink_links);
706 EXPORT_SYMBOL(rtnetlink_put_metrics);
707 EXPORT_SYMBOL(rtnl);
708 EXPORT_SYMBOL(rtnl_lock);
709 EXPORT_SYMBOL(rtnl_lock_interruptible);
710 EXPORT_SYMBOL(rtnl_sem);
711 EXPORT_SYMBOL(rtnl_unlock);