[RTNETLINK]: Add rtnetlink notification interface
[safe/jmp/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/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/sched.h>
25 #include <linux/timer.h>
26 #include <linux/string.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/fcntl.h>
30 #include <linux/mm.h>
31 #include <linux/slab.h>
32 #include <linux/interrupt.h>
33 #include <linux/capability.h>
34 #include <linux/skbuff.h>
35 #include <linux/init.h>
36 #include <linux/security.h>
37 #include <linux/mutex.h>
38 #include <linux/if_addr.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/netlink.h>
55 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
56 #include <linux/wireless.h>
57 #include <net/iw_handler.h>
58 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
59
60 static DEFINE_MUTEX(rtnl_mutex);
61
62 void rtnl_lock(void)
63 {
64         mutex_lock(&rtnl_mutex);
65 }
66
67 void __rtnl_unlock(void)
68 {
69         mutex_unlock(&rtnl_mutex);
70 }
71
72 void rtnl_unlock(void)
73 {
74         mutex_unlock(&rtnl_mutex);
75         if (rtnl && rtnl->sk_receive_queue.qlen)
76                 rtnl->sk_data_ready(rtnl, 0);
77         netdev_run_todo();
78 }
79
80 int rtnl_trylock(void)
81 {
82         return mutex_trylock(&rtnl_mutex);
83 }
84
85 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
86 {
87         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
88
89         while (RTA_OK(rta, len)) {
90                 unsigned flavor = rta->rta_type;
91                 if (flavor && flavor <= maxattr)
92                         tb[flavor-1] = rta;
93                 rta = RTA_NEXT(rta, len);
94         }
95         return 0;
96 }
97
98 struct sock *rtnl;
99
100 struct rtnetlink_link * rtnetlink_links[NPROTO];
101
102 static const int rtm_min[RTM_NR_FAMILIES] =
103 {
104         [RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
105         [RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
106         [RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
107         [RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
108         [RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
109         [RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
110         [RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
111         [RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
112         [RTM_FAM(RTM_NEWPREFIX)]    = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
113         [RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
114         [RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
115 };
116
117 static const int rta_max[RTM_NR_FAMILIES] =
118 {
119         [RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
120         [RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
121         [RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
122         [RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,
123         [RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
124         [RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
125         [RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
126         [RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
127 };
128
129 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
130 {
131         struct rtattr *rta;
132         int size = RTA_LENGTH(attrlen);
133
134         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
135         rta->rta_type = attrtype;
136         rta->rta_len = size;
137         memcpy(RTA_DATA(rta), data, attrlen);
138         memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
139 }
140
141 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
142 {
143         size_t ret = RTA_PAYLOAD(rta);
144         char *src = RTA_DATA(rta);
145
146         if (ret > 0 && src[ret - 1] == '\0')
147                 ret--;
148         if (size > 0) {
149                 size_t len = (ret >= size) ? size - 1 : ret;
150                 memset(dest, 0, size);
151                 memcpy(dest, src, len);
152         }
153         return ret;
154 }
155
156 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
157 {
158         int err = 0;
159
160         NETLINK_CB(skb).dst_group = group;
161         if (echo)
162                 atomic_inc(&skb->users);
163         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
164         if (echo)
165                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
166         return err;
167 }
168
169 int rtnl_unicast(struct sk_buff *skb, u32 pid)
170 {
171         return nlmsg_unicast(rtnl, skb, pid);
172 }
173
174 int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
175                 struct nlmsghdr *nlh, gfp_t flags)
176 {
177         int report = 0;
178
179         if (nlh)
180                 report = nlmsg_report(nlh);
181
182         return nlmsg_notify(rtnl, skb, pid, group, report, flags);
183 }
184
185 void rtnl_set_sk_err(u32 group, int error)
186 {
187         netlink_set_err(rtnl, 0, group, error);
188 }
189
190 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
191 {
192         struct rtattr *mx = (struct rtattr*)skb->tail;
193         int i;
194
195         RTA_PUT(skb, RTA_METRICS, 0, NULL);
196         for (i=0; i<RTAX_MAX; i++) {
197                 if (metrics[i])
198                         RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
199         }
200         mx->rta_len = skb->tail - (u8*)mx;
201         if (mx->rta_len == RTA_LENGTH(0))
202                 skb_trim(skb, (u8*)mx - skb->data);
203         return 0;
204
205 rtattr_failure:
206         skb_trim(skb, (u8*)mx - skb->data);
207         return -1;
208 }
209
210
211 static void set_operstate(struct net_device *dev, unsigned char transition)
212 {
213         unsigned char operstate = dev->operstate;
214
215         switch(transition) {
216         case IF_OPER_UP:
217                 if ((operstate == IF_OPER_DORMANT ||
218                      operstate == IF_OPER_UNKNOWN) &&
219                     !netif_dormant(dev))
220                         operstate = IF_OPER_UP;
221                 break;
222
223         case IF_OPER_DORMANT:
224                 if (operstate == IF_OPER_UP ||
225                     operstate == IF_OPER_UNKNOWN)
226                         operstate = IF_OPER_DORMANT;
227                 break;
228         };
229
230         if (dev->operstate != operstate) {
231                 write_lock_bh(&dev_base_lock);
232                 dev->operstate = operstate;
233                 write_unlock_bh(&dev_base_lock);
234                 netdev_state_change(dev);
235         }
236 }
237
238 static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
239                                  struct net_device_stats *b)
240 {
241         a->rx_packets = b->rx_packets;
242         a->tx_packets = b->tx_packets;
243         a->rx_bytes = b->rx_bytes;
244         a->tx_bytes = b->tx_bytes;
245         a->rx_errors = b->rx_errors;
246         a->tx_errors = b->tx_errors;
247         a->rx_dropped = b->rx_dropped;
248         a->tx_dropped = b->tx_dropped;
249
250         a->multicast = b->multicast;
251         a->collisions = b->collisions;
252
253         a->rx_length_errors = b->rx_length_errors;
254         a->rx_over_errors = b->rx_over_errors;
255         a->rx_crc_errors = b->rx_crc_errors;
256         a->rx_frame_errors = b->rx_frame_errors;
257         a->rx_fifo_errors = b->rx_fifo_errors;
258         a->rx_missed_errors = b->rx_missed_errors;
259
260         a->tx_aborted_errors = b->tx_aborted_errors;
261         a->tx_carrier_errors = b->tx_carrier_errors;
262         a->tx_fifo_errors = b->tx_fifo_errors;
263         a->tx_heartbeat_errors = b->tx_heartbeat_errors;
264         a->tx_window_errors = b->tx_window_errors;
265
266         a->rx_compressed = b->rx_compressed;
267         a->tx_compressed = b->tx_compressed;
268 };
269
270 static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
271                             void *iwbuf, int iwbuflen, int type, u32 pid,
272                             u32 seq, u32 change, unsigned int flags)
273 {
274         struct ifinfomsg *ifm;
275         struct nlmsghdr *nlh;
276
277         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
278         if (nlh == NULL)
279                 return -ENOBUFS;
280
281         ifm = nlmsg_data(nlh);
282         ifm->ifi_family = AF_UNSPEC;
283         ifm->__ifi_pad = 0;
284         ifm->ifi_type = dev->type;
285         ifm->ifi_index = dev->ifindex;
286         ifm->ifi_flags = dev_get_flags(dev);
287         ifm->ifi_change = change;
288
289         NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
290         NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
291         NLA_PUT_U32(skb, IFLA_WEIGHT, dev->weight);
292         NLA_PUT_U8(skb, IFLA_OPERSTATE,
293                    netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
294         NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
295         NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
296
297         if (dev->ifindex != dev->iflink)
298                 NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
299
300         if (dev->master)
301                 NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
302
303         if (dev->qdisc_sleeping)
304                 NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
305
306         if (1) {
307                 struct rtnl_link_ifmap map = {
308                         .mem_start   = dev->mem_start,
309                         .mem_end     = dev->mem_end,
310                         .base_addr   = dev->base_addr,
311                         .irq         = dev->irq,
312                         .dma         = dev->dma,
313                         .port        = dev->if_port,
314                 };
315                 NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
316         }
317
318         if (dev->addr_len) {
319                 NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
320                 NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
321         }
322
323         if (dev->get_stats) {
324                 struct net_device_stats *stats = dev->get_stats(dev);
325                 if (stats) {
326                         struct nlattr *attr;
327
328                         attr = nla_reserve(skb, IFLA_STATS,
329                                            sizeof(struct rtnl_link_stats));
330                         if (attr == NULL)
331                                 goto nla_put_failure;
332
333                         copy_rtnl_link_stats(nla_data(attr), stats);
334                 }
335         }
336
337         if (iwbuf)
338                 NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
339
340         return nlmsg_end(skb, nlh);
341
342 nla_put_failure:
343         return nlmsg_cancel(skb, nlh);
344 }
345
346 static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
347 {
348         int idx;
349         int s_idx = cb->args[0];
350         struct net_device *dev;
351
352         read_lock(&dev_base_lock);
353         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
354                 if (idx < s_idx)
355                         continue;
356                 if (rtnl_fill_ifinfo(skb, dev, NULL, 0, RTM_NEWLINK,
357                                      NETLINK_CB(cb->skb).pid,
358                                      cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
359                         break;
360         }
361         read_unlock(&dev_base_lock);
362         cb->args[0] = idx;
363
364         return skb->len;
365 }
366
367 static struct nla_policy ifla_policy[IFLA_MAX+1] __read_mostly = {
368         [IFLA_IFNAME]           = { .type = NLA_STRING },
369         [IFLA_MAP]              = { .minlen = sizeof(struct rtnl_link_ifmap) },
370         [IFLA_MTU]              = { .type = NLA_U32 },
371         [IFLA_TXQLEN]           = { .type = NLA_U32 },
372         [IFLA_WEIGHT]           = { .type = NLA_U32 },
373         [IFLA_OPERSTATE]        = { .type = NLA_U8 },
374         [IFLA_LINKMODE]         = { .type = NLA_U8 },
375 };
376
377 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
378 {
379         struct ifinfomsg *ifm;
380         struct net_device *dev;
381         int err, send_addr_notify = 0, modified = 0;
382         struct nlattr *tb[IFLA_MAX+1];
383         char ifname[IFNAMSIZ];
384
385         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
386         if (err < 0)
387                 goto errout;
388
389         if (tb[IFLA_IFNAME] &&
390             nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ) >= IFNAMSIZ)
391                 return -EINVAL;
392
393         err = -EINVAL;
394         ifm = nlmsg_data(nlh);
395         if (ifm->ifi_index >= 0)
396                 dev = dev_get_by_index(ifm->ifi_index);
397         else if (tb[IFLA_IFNAME])
398                 dev = dev_get_by_name(ifname);
399         else
400                 goto errout;
401
402         if (dev == NULL) {
403                 err = -ENODEV;
404                 goto errout;
405         }
406
407         if (tb[IFLA_ADDRESS] &&
408             nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
409                 goto errout_dev;
410
411         if (tb[IFLA_BROADCAST] &&
412             nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
413                 goto errout_dev;
414
415         if (tb[IFLA_MAP]) {
416                 struct rtnl_link_ifmap *u_map;
417                 struct ifmap k_map;
418
419                 if (!dev->set_config) {
420                         err = -EOPNOTSUPP;
421                         goto errout_dev;
422                 }
423
424                 if (!netif_device_present(dev)) {
425                         err = -ENODEV;
426                         goto errout_dev;
427                 }
428
429                 u_map = nla_data(tb[IFLA_MAP]);
430                 k_map.mem_start = (unsigned long) u_map->mem_start;
431                 k_map.mem_end = (unsigned long) u_map->mem_end;
432                 k_map.base_addr = (unsigned short) u_map->base_addr;
433                 k_map.irq = (unsigned char) u_map->irq;
434                 k_map.dma = (unsigned char) u_map->dma;
435                 k_map.port = (unsigned char) u_map->port;
436
437                 err = dev->set_config(dev, &k_map);
438                 if (err < 0)
439                         goto errout_dev;
440
441                 modified = 1;
442         }
443
444         if (tb[IFLA_ADDRESS]) {
445                 struct sockaddr *sa;
446                 int len;
447
448                 if (!dev->set_mac_address) {
449                         err = -EOPNOTSUPP;
450                         goto errout_dev;
451                 }
452
453                 if (!netif_device_present(dev)) {
454                         err = -ENODEV;
455                         goto errout_dev;
456                 }
457
458                 len = sizeof(sa_family_t) + dev->addr_len;
459                 sa = kmalloc(len, GFP_KERNEL);
460                 if (!sa) {
461                         err = -ENOMEM;
462                         goto errout_dev;
463                 }
464                 sa->sa_family = dev->type;
465                 memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
466                        dev->addr_len);
467                 err = dev->set_mac_address(dev, sa);
468                 kfree(sa);
469                 if (err)
470                         goto errout_dev;
471                 send_addr_notify = 1;
472                 modified = 1;
473         }
474
475         if (tb[IFLA_MTU]) {
476                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
477                 if (err < 0)
478                         goto errout_dev;
479                 modified = 1;
480         }
481
482         /*
483          * Interface selected by interface index but interface
484          * name provided implies that a name change has been
485          * requested.
486          */
487         if (ifm->ifi_index >= 0 && ifname[0]) {
488                 err = dev_change_name(dev, ifname);
489                 if (err < 0)
490                         goto errout_dev;
491                 modified = 1;
492         }
493
494 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
495         if (tb[IFLA_WIRELESS]) {
496                 /* Call Wireless Extensions.
497                  * Various stuff checked in there... */
498                 err = wireless_rtnetlink_set(dev, nla_data(tb[IFLA_WIRELESS]),
499                                              nla_len(tb[IFLA_WIRELESS]));
500                 if (err < 0)
501                         goto errout_dev;
502         }
503 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
504
505         if (tb[IFLA_BROADCAST]) {
506                 nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
507                 send_addr_notify = 1;
508         }
509
510
511         if (ifm->ifi_flags)
512                 dev_change_flags(dev, ifm->ifi_flags);
513
514         if (tb[IFLA_TXQLEN])
515                 dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
516
517         if (tb[IFLA_WEIGHT])
518                 dev->weight = nla_get_u32(tb[IFLA_WEIGHT]);
519
520         if (tb[IFLA_OPERSTATE])
521                 set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
522
523         if (tb[IFLA_LINKMODE]) {
524                 write_lock_bh(&dev_base_lock);
525                 dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
526                 write_unlock_bh(&dev_base_lock);
527         }
528
529         err = 0;
530
531 errout_dev:
532         if (err < 0 && modified && net_ratelimit())
533                 printk(KERN_WARNING "A link change request failed with "
534                        "some changes comitted already. Interface %s may "
535                        "have been left with an inconsistent configuration, "
536                        "please check.\n", dev->name);
537
538         if (send_addr_notify)
539                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
540
541         dev_put(dev);
542 errout:
543         return err;
544 }
545
546 static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
547 {
548         struct ifinfomsg *ifm;
549         struct nlattr *tb[IFLA_MAX+1];
550         struct net_device *dev = NULL;
551         struct sk_buff *nskb;
552         char *iw_buf = NULL, *iw = NULL;
553         int iw_buf_len = 0;
554         int err, payload;
555
556         err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
557         if (err < 0)
558                 goto errout;
559
560         ifm = nlmsg_data(nlh);
561         if (ifm->ifi_index >= 0) {
562                 dev = dev_get_by_index(ifm->ifi_index);
563                 if (dev == NULL)
564                         return -ENODEV;
565         } else
566                 return -EINVAL;
567
568
569 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
570         if (tb[IFLA_WIRELESS]) {
571                 /* Call Wireless Extensions. We need to know the size before
572                  * we can alloc. Various stuff checked in there... */
573                 err = wireless_rtnetlink_get(dev, nla_data(tb[IFLA_WIRELESS]),
574                                              nla_len(tb[IFLA_WIRELESS]),
575                                              &iw_buf, &iw_buf_len);
576                 if (err < 0)
577                         goto errout;
578
579                 iw += IW_EV_POINT_OFF;
580         }
581 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
582
583         payload = NLMSG_ALIGN(sizeof(struct ifinfomsg) +
584                               nla_total_size(iw_buf_len));
585         nskb = nlmsg_new(nlmsg_total_size(payload), GFP_KERNEL);
586         if (nskb == NULL) {
587                 err = -ENOBUFS;
588                 goto errout;
589         }
590
591         err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK,
592                                NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0);
593         if (err <= 0) {
594                 kfree_skb(skb);
595                 goto errout;
596         }
597
598         err = rtnl_unicast(skb, NETLINK_CB(skb).pid);
599 errout:
600         kfree(iw_buf);
601         dev_put(dev);
602
603         return err;
604 }
605
606 static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
607 {
608         int idx;
609         int s_idx = cb->family;
610
611         if (s_idx == 0)
612                 s_idx = 1;
613         for (idx=1; idx<NPROTO; idx++) {
614                 int type = cb->nlh->nlmsg_type-RTM_BASE;
615                 if (idx < s_idx || idx == PF_PACKET)
616                         continue;
617                 if (rtnetlink_links[idx] == NULL ||
618                     rtnetlink_links[idx][type].dumpit == NULL)
619                         continue;
620                 if (idx > s_idx)
621                         memset(&cb->args[0], 0, sizeof(cb->args));
622                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
623                         break;
624         }
625         cb->family = idx;
626
627         return skb->len;
628 }
629
630 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
631 {
632         struct sk_buff *skb;
633         int size = NLMSG_SPACE(sizeof(struct ifinfomsg) +
634                                sizeof(struct rtnl_link_ifmap) +
635                                sizeof(struct rtnl_link_stats) + 128);
636
637         skb = nlmsg_new(size, GFP_KERNEL);
638         if (!skb)
639                 return;
640
641         if (rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0) < 0) {
642                 kfree_skb(skb);
643                 return;
644         }
645         NETLINK_CB(skb).dst_group = RTNLGRP_LINK;
646         netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL);
647 }
648
649 /* Protected by RTNL sempahore.  */
650 static struct rtattr **rta_buf;
651 static int rtattr_max;
652
653 /* Process one rtnetlink message. */
654
655 static __inline__ int
656 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
657 {
658         struct rtnetlink_link *link;
659         struct rtnetlink_link *link_tab;
660         int sz_idx, kind;
661         int min_len;
662         int family;
663         int type;
664         int err;
665
666         /* Only requests are handled by kernel now */
667         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
668                 return 0;
669
670         type = nlh->nlmsg_type;
671
672         /* A control message: ignore them */
673         if (type < RTM_BASE)
674                 return 0;
675
676         /* Unknown message: reply with EINVAL */
677         if (type > RTM_MAX)
678                 goto err_inval;
679
680         type -= RTM_BASE;
681
682         /* All the messages must have at least 1 byte length */
683         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
684                 return 0;
685
686         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
687         if (family >= NPROTO) {
688                 *errp = -EAFNOSUPPORT;
689                 return -1;
690         }
691
692         link_tab = rtnetlink_links[family];
693         if (link_tab == NULL)
694                 link_tab = rtnetlink_links[PF_UNSPEC];
695         link = &link_tab[type];
696
697         sz_idx = type>>2;
698         kind = type&3;
699
700         if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN)) {
701                 *errp = -EPERM;
702                 return -1;
703         }
704
705         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
706                 if (link->dumpit == NULL)
707                         link = &(rtnetlink_links[PF_UNSPEC][type]);
708
709                 if (link->dumpit == NULL)
710                         goto err_inval;
711
712                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
713                                                 link->dumpit, NULL)) != 0) {
714                         return -1;
715                 }
716
717                 netlink_queue_skip(nlh, skb);
718                 return -1;
719         }
720
721         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
722
723         min_len = rtm_min[sz_idx];
724         if (nlh->nlmsg_len < min_len)
725                 goto err_inval;
726
727         if (nlh->nlmsg_len > min_len) {
728                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
729                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
730
731                 while (RTA_OK(attr, attrlen)) {
732                         unsigned flavor = attr->rta_type;
733                         if (flavor) {
734                                 if (flavor > rta_max[sz_idx])
735                                         goto err_inval;
736                                 rta_buf[flavor-1] = attr;
737                         }
738                         attr = RTA_NEXT(attr, attrlen);
739                 }
740         }
741
742         if (link->doit == NULL)
743                 link = &(rtnetlink_links[PF_UNSPEC][type]);
744         if (link->doit == NULL)
745                 goto err_inval;
746         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
747
748         *errp = err;
749         return err;
750
751 err_inval:
752         *errp = -EINVAL;
753         return -1;
754 }
755
756 static void rtnetlink_rcv(struct sock *sk, int len)
757 {
758         unsigned int qlen = 0;
759
760         do {
761                 mutex_lock(&rtnl_mutex);
762                 netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
763                 mutex_unlock(&rtnl_mutex);
764
765                 netdev_run_todo();
766         } while (qlen);
767 }
768
769 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
770 {
771         [RTM_GETLINK     - RTM_BASE] = { .doit   = rtnl_getlink,
772                                          .dumpit = rtnl_dump_ifinfo      },
773         [RTM_SETLINK     - RTM_BASE] = { .doit   = rtnl_setlink          },
774         [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
775         [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnl_dump_all         },
776         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
777         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
778         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
779 #ifdef CONFIG_FIB_RULES
780         [RTM_NEWRULE     - RTM_BASE] = { .doit   = fib_nl_newrule        },
781         [RTM_DELRULE     - RTM_BASE] = { .doit   = fib_nl_delrule        },
782 #endif
783         [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnl_dump_all         },
784         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
785         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
786 };
787
788 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
789 {
790         struct net_device *dev = ptr;
791         switch (event) {
792         case NETDEV_UNREGISTER:
793                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
794                 break;
795         case NETDEV_REGISTER:
796                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
797                 break;
798         case NETDEV_UP:
799         case NETDEV_DOWN:
800                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
801                 break;
802         case NETDEV_CHANGE:
803         case NETDEV_GOING_DOWN:
804                 break;
805         default:
806                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
807                 break;
808         }
809         return NOTIFY_DONE;
810 }
811
812 static struct notifier_block rtnetlink_dev_notifier = {
813         .notifier_call  = rtnetlink_event,
814 };
815
816 void __init rtnetlink_init(void)
817 {
818         int i;
819
820         rtattr_max = 0;
821         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
822                 if (rta_max[i] > rtattr_max)
823                         rtattr_max = rta_max[i];
824         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
825         if (!rta_buf)
826                 panic("rtnetlink_init: cannot allocate rta_buf\n");
827
828         rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
829                                      THIS_MODULE);
830         if (rtnl == NULL)
831                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
832         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
833         register_netdevice_notifier(&rtnetlink_dev_notifier);
834         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
835         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
836 }
837
838 EXPORT_SYMBOL(__rta_fill);
839 EXPORT_SYMBOL(rtattr_strlcpy);
840 EXPORT_SYMBOL(rtattr_parse);
841 EXPORT_SYMBOL(rtnetlink_links);
842 EXPORT_SYMBOL(rtnetlink_put_metrics);
843 EXPORT_SYMBOL(rtnl);
844 EXPORT_SYMBOL(rtnl_lock);
845 EXPORT_SYMBOL(rtnl_trylock);
846 EXPORT_SYMBOL(rtnl_unlock);
847 EXPORT_SYMBOL(rtnl_unicast);
848 EXPORT_SYMBOL(rtnl_notify);
849 EXPORT_SYMBOL(rtnl_set_sk_err);