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_NR_FAMILIES] =
  90 {
  91         [RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
  92         [RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
  93         [RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
  94         [RTM_FAM(RTM_NEWNEIGH)]     = NLMSG_LENGTH(sizeof(struct ndmsg)),
  95         [RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct rtmsg)),
  96         [RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
  97         [RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
  98         [RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
  99         [RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
 100         [RTM_FAM(RTM_NEWPREFIX)]    = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 101         [RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 102         [RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 103         [RTM_FAM(RTM_NEWNEIGHTBL)]  = NLMSG_LENGTH(sizeof(struct ndtmsg)),
 104 };
 105
 106 static const int rta_max[RTM_NR_FAMILIES] =
 107 {
 108         [RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
 109         [RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
 110         [RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
 111         [RTM_FAM(RTM_NEWNEIGH)]     = NDA_MAX,
 112         [RTM_FAM(RTM_NEWRULE)]      = RTA_MAX,
 113         [RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
 114         [RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
 115         [RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
 116         [RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
 117         [RTM_FAM(RTM_NEWNEIGHTBL)]  = NDTA_MAX,
 118 };
 119
 120 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
 121 {
 122         struct rtattr *rta;
 123         int size = RTA_LENGTH(attrlen);
 124
 125         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
 126         rta->rta_type = attrtype;
 127         rta->rta_len = size;
 128         memcpy(RTA_DATA(rta), data, attrlen);
 129         memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
 130 }
 131
 132 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
 133 {
 134         size_t ret = RTA_PAYLOAD(rta);
 135         char *src = RTA_DATA(rta);
 136
 137         if (ret > 0 && src[ret - 1] == '\0')
 138                 ret--;
 139         if (size > 0) {
 140                 size_t len = (ret >= size) ? size - 1 : ret;
 141                 memset(dest, 0, size);
 142                 memcpy(dest, src, len);
 143         }
 144         return ret;
 145 }
 146
 147 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
 148 {
 149         int err = 0;
 150
 151         NETLINK_CB(skb).dst_group = group;
 152         if (echo)
 153                 atomic_inc(&skb->users);
 154         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
 155         if (echo)
 156                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 157         return err;
 158 }
 159
 160 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
 161 {
 162         struct rtattr *mx = (struct rtattr*)skb->tail;
 163         int i;
 164
 165         RTA_PUT(skb, RTA_METRICS, 0, NULL);
 166         for (i=0; i<RTAX_MAX; i++) {
 167                 if (metrics[i])
 168                         RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
 169         }
 170         mx->rta_len = skb->tail - (u8*)mx;
 171         if (mx->rta_len == RTA_LENGTH(0))
 172                 skb_trim(skb, (u8*)mx - skb->data);
 173         return 0;
 174
 175 rtattr_failure:
 176         skb_trim(skb, (u8*)mx - skb->data);
 177         return -1;
 178 }
 179
 180
 181 static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 182                                  int type, u32 pid, u32 seq, u32 change,
 183                                  unsigned int flags)
 184 {
 185         struct ifinfomsg *r;
 186         struct nlmsghdr  *nlh;
 187         unsigned char    *b = skb->tail;
 188
 189         nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*r), flags);
 190         r = NLMSG_DATA(nlh);
 191         r->ifi_family = AF_UNSPEC;
 192         r->__ifi_pad = 0;
 193         r->ifi_type = dev->type;
 194         r->ifi_index = dev->ifindex;
 195         r->ifi_flags = dev_get_flags(dev);
 196         r->ifi_change = change;
 197
 198         RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name);
 199
 200         if (1) {
 201                 u32 txqlen = dev->tx_queue_len;
 202                 RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen);
 203         }
 204
 205         if (1) {
 206                 u32 weight = dev->weight;
 207                 RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight);
 208         }
 209
 210         if (1) {
 211                 struct rtnl_link_ifmap map = {
 212                         .mem_start   = dev->mem_start,
 213                         .mem_end     = dev->mem_end,
 214                         .base_addr   = dev->base_addr,
 215                         .irq         = dev->irq,
 216                         .dma         = dev->dma,
 217                         .port        = dev->if_port,
 218                 };
 219                 RTA_PUT(skb, IFLA_MAP, sizeof(map), &map);
 220         }
 221
 222         if (dev->addr_len) {
 223                 RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
 224                 RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
 225         }
 226
 227         if (1) {
 228                 u32 mtu = dev->mtu;
 229                 RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu);
 230         }
 231
 232         if (dev->ifindex != dev->iflink) {
 233                 u32 iflink = dev->iflink;
 234                 RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink);
 235         }
 236
 237         if (dev->qdisc_sleeping)
 238                 RTA_PUT(skb, IFLA_QDISC,
 239                         strlen(dev->qdisc_sleeping->ops->id) + 1,
 240                         dev->qdisc_sleeping->ops->id);
 241
 242         if (dev->master) {
 243                 u32 master = dev->master->ifindex;
 244                 RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master);
 245         }
 246
 247         if (dev->get_stats) {
 248                 unsigned long *stats = (unsigned long*)dev->get_stats(dev);
 249                 if (stats) {
 250                         struct rtattr  *a;
 251                         __u32          *s;
 252                         int             i;
 253                         int             n = sizeof(struct rtnl_link_stats)/4;
 254
 255                         a = __RTA_PUT(skb, IFLA_STATS, n*4);
 256                         s = RTA_DATA(a);
 257                         for (i=0; i<n; i++)
 258                                 s[i] = stats[i];
 259                 }
 260         }
 261         nlh->nlmsg_len = skb->tail - b;
 262         return skb->len;
 263
 264 nlmsg_failure:
 265 rtattr_failure:
 266         skb_trim(skb, b - skb->data);
 267         return -1;
 268 }
 269
 270 static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 271 {
 272         int idx;
 273         int s_idx = cb->args[0];
 274         struct net_device *dev;
 275
 276         read_lock(&dev_base_lock);
 277         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
 278                 if (idx < s_idx)
 279                         continue;
 280                 if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK,
 281                                           NETLINK_CB(cb->skb).pid,
 282                                           cb->nlh->nlmsg_seq, 0,
 283                                           NLM_F_MULTI) <= 0)
 284                         break;
 285         }
 286         read_unlock(&dev_base_lock);
 287         cb->args[0] = idx;
 288
 289         return skb->len;
 290 }
 291
 292 static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 293 {
 294         struct ifinfomsg  *ifm = NLMSG_DATA(nlh);
 295         struct rtattr    **ida = arg;
 296         struct net_device *dev;
 297         int err, send_addr_notify = 0;
 298
 299         if (ifm->ifi_index >= 0)
 300                 dev = dev_get_by_index(ifm->ifi_index);
 301         else if (ida[IFLA_IFNAME - 1]) {
 302                 char ifname[IFNAMSIZ];
 303
 304                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
 305                                    IFNAMSIZ) >= IFNAMSIZ)
 306                         return -EINVAL;
 307                 dev = dev_get_by_name(ifname);
 308         } else
 309                 return -EINVAL;
 310
 311         if (!dev)
 312                 return -ENODEV;
 313
 314         err = -EINVAL;
 315
 316         if (ifm->ifi_flags)
 317                 dev_change_flags(dev, ifm->ifi_flags);
 318
 319         if (ida[IFLA_MAP - 1]) {
 320                 struct rtnl_link_ifmap *u_map;
 321                 struct ifmap k_map;
 322
 323                 if (!dev->set_config) {
 324                         err = -EOPNOTSUPP;
 325                         goto out;
 326                 }
 327
 328                 if (!netif_device_present(dev)) {
 329                         err = -ENODEV;
 330                         goto out;
 331                 }
 332
 333                 if (ida[IFLA_MAP - 1]->rta_len != RTA_LENGTH(sizeof(*u_map)))
 334                         goto out;
 335
 336                 u_map = RTA_DATA(ida[IFLA_MAP - 1]);
 337
 338                 k_map.mem_start = (unsigned long) u_map->mem_start;
 339                 k_map.mem_end = (unsigned long) u_map->mem_end;
 340                 k_map.base_addr = (unsigned short) u_map->base_addr;
 341                 k_map.irq = (unsigned char) u_map->irq;
 342                 k_map.dma = (unsigned char) u_map->dma;
 343                 k_map.port = (unsigned char) u_map->port;
 344
 345                 err = dev->set_config(dev, &k_map);
 346
 347                 if (err)
 348                         goto out;
 349         }
 350
 351         if (ida[IFLA_ADDRESS - 1]) {
 352                 if (!dev->set_mac_address) {
 353                         err = -EOPNOTSUPP;
 354                         goto out;
 355                 }
 356                 if (!netif_device_present(dev)) {
 357                         err = -ENODEV;
 358                         goto out;
 359                 }
 360                 if (ida[IFLA_ADDRESS - 1]->rta_len != RTA_LENGTH(dev->addr_len))
 361                         goto out;
 362
 363                 err = dev->set_mac_address(dev, RTA_DATA(ida[IFLA_ADDRESS - 1]));
 364                 if (err)
 365                         goto out;
 366                 send_addr_notify = 1;
 367         }
 368
 369         if (ida[IFLA_BROADCAST - 1]) {
 370                 if (ida[IFLA_BROADCAST - 1]->rta_len != RTA_LENGTH(dev->addr_len))
 371                         goto out;
 372                 memcpy(dev->broadcast, RTA_DATA(ida[IFLA_BROADCAST - 1]),
 373                        dev->addr_len);
 374                 send_addr_notify = 1;
 375         }
 376
 377         if (ida[IFLA_MTU - 1]) {
 378                 if (ida[IFLA_MTU - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 379                         goto out;
 380                 err = dev_set_mtu(dev, *((u32 *) RTA_DATA(ida[IFLA_MTU - 1])));
 381
 382                 if (err)
 383                         goto out;
 384
 385         }
 386
 387         if (ida[IFLA_TXQLEN - 1]) {
 388                 if (ida[IFLA_TXQLEN - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 389                         goto out;
 390
 391                 dev->tx_queue_len = *((u32 *) RTA_DATA(ida[IFLA_TXQLEN - 1]));
 392         }
 393
 394         if (ida[IFLA_WEIGHT - 1]) {
 395                 if (ida[IFLA_WEIGHT - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 396                         goto out;
 397
 398                 dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1]));
 399         }
 400
 401         if (ifm->ifi_index >= 0 && ida[IFLA_IFNAME - 1]) {
 402                 char ifname[IFNAMSIZ];
 403
 404                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
 405                                    IFNAMSIZ) >= IFNAMSIZ)
 406                         goto out;
 407                 err = dev_change_name(dev, ifname);
 408                 if (err)
 409                         goto out;
 410         }
 411
 412         err = 0;
 413
 414 out:
 415         if (send_addr_notify)
 416                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 417
 418         dev_put(dev);
 419         return err;
 420 }
 421
 422 static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 423 {
 424         int idx;
 425         int s_idx = cb->family;
 426
 427         if (s_idx == 0)
 428                 s_idx = 1;
 429         for (idx=1; idx<NPROTO; idx++) {
 430                 int type = cb->nlh->nlmsg_type-RTM_BASE;
 431                 if (idx < s_idx || idx == PF_PACKET)
 432                         continue;
 433                 if (rtnetlink_links[idx] == NULL ||
 434                     rtnetlink_links[idx][type].dumpit == NULL)
 435                         continue;
 436                 if (idx > s_idx)
 437                         memset(&cb->args[0], 0, sizeof(cb->args));
 438                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
 439                         break;
 440         }
 441         cb->family = idx;
 442
 443         return skb->len;
 444 }
 445
 446 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
 447 {
 448         struct sk_buff *skb;
 449         int size = NLMSG_SPACE(sizeof(struct ifinfomsg) +
 450                                sizeof(struct rtnl_link_ifmap) +
 451                                sizeof(struct rtnl_link_stats) + 128);
 452
 453         skb = alloc_skb(size, GFP_KERNEL);
 454         if (!skb)
 455                 return;
 456
 457         if (rtnetlink_fill_ifinfo(skb, dev, type, current->pid, 0, change, 0) < 0) {
 458                 kfree_skb(skb);
 459                 return;
 460         }
 461         NETLINK_CB(skb).dst_group = RTNLGRP_LINK;
 462         netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL);
 463 }
 464
 465 static int rtnetlink_done(struct netlink_callback *cb)
 466 {
 467         return 0;
 468 }
 469
 470 /* Protected by RTNL sempahore.  */
 471 static struct rtattr **rta_buf;
 472 static int rtattr_max;
 473
 474 /* Process one rtnetlink message. */
 475
 476 static __inline__ int
 477 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 478 {
 479         struct rtnetlink_link *link;
 480         struct rtnetlink_link *link_tab;
 481         int sz_idx, kind;
 482         int min_len;
 483         int family;
 484         int type;
 485         int err;
 486
 487         /* Only requests are handled by kernel now */
 488         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 489                 return 0;
 490
 491         type = nlh->nlmsg_type;
 492
 493         /* A control message: ignore them */
 494         if (type < RTM_BASE)
 495                 return 0;
 496
 497         /* Unknown message: reply with EINVAL */
 498         if (type > RTM_MAX)
 499                 goto err_inval;
 500
 501         type -= RTM_BASE;
 502
 503         /* All the messages must have at least 1 byte length */
 504         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
 505                 return 0;
 506
 507         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
 508         if (family >= NPROTO) {
 509                 *errp = -EAFNOSUPPORT;
 510                 return -1;
 511         }
 512
 513         link_tab = rtnetlink_links[family];
 514         if (link_tab == NULL)
 515                 link_tab = rtnetlink_links[PF_UNSPEC];
 516         link = &link_tab[type];
 517
 518         sz_idx = type>>2;
 519         kind = type&3;
 520
 521         if (kind != 2 && security_netlink_recv(skb)) {
 522                 *errp = -EPERM;
 523                 return -1;
 524         }
 525
 526         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
 527                 u32 rlen;
 528
 529                 if (link->dumpit == NULL)
 530                         link = &(rtnetlink_links[PF_UNSPEC][type]);
 531
 532                 if (link->dumpit == NULL)
 533                         goto err_inval;
 534
 535                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
 536                                                 link->dumpit,
 537                                                 rtnetlink_done)) != 0) {
 538                         return -1;
 539                 }
 540                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 541                 if (rlen > skb->len)
 542                         rlen = skb->len;
 543                 skb_pull(skb, rlen);
 544                 return -1;
 545         }
 546
 547         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
 548
 549         min_len = rtm_min[sz_idx];
 550         if (nlh->nlmsg_len < min_len)
 551                 goto err_inval;
 552
 553         if (nlh->nlmsg_len > min_len) {
 554                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
 555                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
 556
 557                 while (RTA_OK(attr, attrlen)) {
 558                         unsigned flavor = attr->rta_type;
 559                         if (flavor) {
 560                                 if (flavor > rta_max[sz_idx])
 561                                         goto err_inval;
 562                                 rta_buf[flavor-1] = attr;
 563                         }
 564                         attr = RTA_NEXT(attr, attrlen);
 565                 }
 566         }
 567
 568         if (link->doit == NULL)
 569                 link = &(rtnetlink_links[PF_UNSPEC][type]);
 570         if (link->doit == NULL)
 571                 goto err_inval;
 572         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
 573
 574         *errp = err;
 575         return err;
 576
 577 err_inval:
 578         *errp = -EINVAL;
 579         return -1;
 580 }
 581
 582 /*
 583  * Process one packet of messages.
 584  * Malformed skbs with wrong lengths of messages are discarded silently.
 585  */
 586
 587 static inline int rtnetlink_rcv_skb(struct sk_buff *skb)
 588 {
 589         int err;
 590         struct nlmsghdr * nlh;
 591
 592         while (skb->len >= NLMSG_SPACE(0)) {
 593                 u32 rlen;
 594
 595                 nlh = (struct nlmsghdr *)skb->data;
 596                 if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
 597                         return 0;
 598                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 599                 if (rlen > skb->len)
 600                         rlen = skb->len;
 601                 if (rtnetlink_rcv_msg(skb, nlh, &err)) {
 602                         /* Not error, but we must interrupt processing here:
 603                          *   Note, that in this case we do not pull message
 604                          *   from skb, it will be processed later.
 605                          */
 606                         if (err == 0)
 607                                 return -1;
 608                         netlink_ack(skb, nlh, err);
 609                 } else if (nlh->nlmsg_flags&NLM_F_ACK)
 610                         netlink_ack(skb, nlh, 0);
 611                 skb_pull(skb, rlen);
 612         }
 613
 614         return 0;
 615 }
 616
 617 /*
 618  *  rtnetlink input queue processing routine:
 619  *      - process as much as there was in the queue upon entry.
 620  *      - feed skbs to rtnetlink_rcv_skb, until it refuse a message,
 621  *        that will occur, when a dump started.
 622  */
 623
 624 static void rtnetlink_rcv(struct sock *sk, int len)
 625 {
 626         unsigned int qlen = skb_queue_len(&sk->sk_receive_queue);
 627
 628         do {
 629                 struct sk_buff *skb;
 630
 631                 rtnl_lock();
 632
 633                 if (qlen > skb_queue_len(&sk->sk_receive_queue))
 634                         qlen = skb_queue_len(&sk->sk_receive_queue);
 635
 636                 for (; qlen; qlen--) {
 637                         skb = skb_dequeue(&sk->sk_receive_queue);
 638                         if (rtnetlink_rcv_skb(skb)) {
 639                                 if (skb->len)
 640                                         skb_queue_head(&sk->sk_receive_queue,
 641                                                        skb);
 642                                 else {
 643                                         kfree_skb(skb);
 644                                         qlen--;
 645                                 }
 646                                 break;
 647                         }
 648                         kfree_skb(skb);
 649                 }
 650
 651                 up(&rtnl_sem);
 652
 653                 netdev_run_todo();
 654         } while (qlen);
 655 }
 656
 657 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
 658 {
 659         [RTM_GETLINK     - RTM_BASE] = { .dumpit = rtnetlink_dump_ifinfo },
 660         [RTM_SETLINK     - RTM_BASE] = { .doit   = do_setlink            },
 661         [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 662         [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 663         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
 664         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
 665         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
 666         [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 667         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
 668         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
 669 };
 670
 671 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
 672 {
 673         struct net_device *dev = ptr;
 674         switch (event) {
 675         case NETDEV_UNREGISTER:
 676                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
 677                 break;
 678         case NETDEV_REGISTER:
 679                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
 680                 break;
 681         case NETDEV_UP:
 682         case NETDEV_DOWN:
 683                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
 684                 break;
 685         case NETDEV_CHANGE:
 686         case NETDEV_GOING_DOWN:
 687                 break;
 688         default:
 689                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
 690                 break;
 691         }
 692         return NOTIFY_DONE;
 693 }
 694
 695 static struct notifier_block rtnetlink_dev_notifier = {
 696         .notifier_call  = rtnetlink_event,
 697 };
 698
 699 void __init rtnetlink_init(void)
 700 {
 701         int i;
 702
 703         rtattr_max = 0;
 704         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
 705                 if (rta_max[i] > rtattr_max)
 706                         rtattr_max = rta_max[i];
 707         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
 708         if (!rta_buf)
 709                 panic("rtnetlink_init: cannot allocate rta_buf\n");
 710
 711         rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
 712                                      THIS_MODULE);
 713         if (rtnl == NULL)
 714                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
 715         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
 716         register_netdevice_notifier(&rtnetlink_dev_notifier);
 717         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
 718         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
 719 }
 720
 721 EXPORT_SYMBOL(__rta_fill);
 722 EXPORT_SYMBOL(rtattr_strlcpy);
 723 EXPORT_SYMBOL(rtattr_parse);
 724 EXPORT_SYMBOL(rtnetlink_links);
 725 EXPORT_SYMBOL(rtnetlink_put_metrics);
 726 EXPORT_SYMBOL(rtnl);
 727 EXPORT_SYMBOL(rtnl_lock);
 728 EXPORT_SYMBOL(rtnl_lock_interruptible);
 729 EXPORT_SYMBOL(rtnl_sem);
 730 EXPORT_SYMBOL(rtnl_unlock);