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