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 #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);