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 #include <linux/mutex.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/netlink.h>
  54 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
  55 #include <linux/wireless.h>
  56 #include <net/iw_handler.h>
  57 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
  58
  59 static DEFINE_MUTEX(rtnl_mutex);
  60
  61 void rtnl_lock(void)
  62 {
  63         mutex_lock(&rtnl_mutex);
  64 }
  65
  66 void __rtnl_unlock(void)
  67 {
  68         mutex_unlock(&rtnl_mutex);
  69 }
  70
  71 void rtnl_unlock(void)
  72 {
  73         mutex_unlock(&rtnl_mutex);
  74         if (rtnl && rtnl->sk_receive_queue.qlen)
  75                 rtnl->sk_data_ready(rtnl, 0);
  76         netdev_run_todo();
  77 }
  78
  79 int rtnl_trylock(void)
  80 {
  81         return mutex_trylock(&rtnl_mutex);
  82 }
  83
  84 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
  85 {
  86         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
  87
  88         while (RTA_OK(rta, len)) {
  89                 unsigned flavor = rta->rta_type;
  90                 if (flavor && flavor <= maxattr)
  91                         tb[flavor-1] = rta;
  92                 rta = RTA_NEXT(rta, len);
  93         }
  94         return 0;
  95 }
  96
  97 struct sock *rtnl;
  98
  99 struct rtnetlink_link * rtnetlink_links[NPROTO];
 100
 101 static const int rtm_min[RTM_NR_FAMILIES] =
 102 {
 103         [RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 104         [RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
 105         [RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
 106         [RTM_FAM(RTM_NEWNEIGH)]     = NLMSG_LENGTH(sizeof(struct ndmsg)),
 107         [RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct rtmsg)),
 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         [RTM_FAM(RTM_NEWNEIGHTBL)]  = NLMSG_LENGTH(sizeof(struct ndtmsg)),
 116 };
 117
 118 static const int rta_max[RTM_NR_FAMILIES] =
 119 {
 120         [RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
 121         [RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
 122         [RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
 123         [RTM_FAM(RTM_NEWNEIGH)]     = NDA_MAX,
 124         [RTM_FAM(RTM_NEWRULE)]      = RTA_MAX,
 125         [RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
 126         [RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
 127         [RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
 128         [RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
 129         [RTM_FAM(RTM_NEWNEIGHTBL)]  = NDTA_MAX,
 130 };
 131
 132 void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
 133 {
 134         struct rtattr *rta;
 135         int size = RTA_LENGTH(attrlen);
 136
 137         rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
 138         rta->rta_type = attrtype;
 139         rta->rta_len = size;
 140         memcpy(RTA_DATA(rta), data, attrlen);
 141         memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
 142 }
 143
 144 size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
 145 {
 146         size_t ret = RTA_PAYLOAD(rta);
 147         char *src = RTA_DATA(rta);
 148
 149         if (ret > 0 && src[ret - 1] == '\0')
 150                 ret--;
 151         if (size > 0) {
 152                 size_t len = (ret >= size) ? size - 1 : ret;
 153                 memset(dest, 0, size);
 154                 memcpy(dest, src, len);
 155         }
 156         return ret;
 157 }
 158
 159 int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
 160 {
 161         int err = 0;
 162
 163         NETLINK_CB(skb).dst_group = group;
 164         if (echo)
 165                 atomic_inc(&skb->users);
 166         netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
 167         if (echo)
 168                 err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 169         return err;
 170 }
 171
 172 int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
 173 {
 174         struct rtattr *mx = (struct rtattr*)skb->tail;
 175         int i;
 176
 177         RTA_PUT(skb, RTA_METRICS, 0, NULL);
 178         for (i=0; i<RTAX_MAX; i++) {
 179                 if (metrics[i])
 180                         RTA_PUT(skb, i+1, sizeof(u32), metrics+i);
 181         }
 182         mx->rta_len = skb->tail - (u8*)mx;
 183         if (mx->rta_len == RTA_LENGTH(0))
 184                 skb_trim(skb, (u8*)mx - skb->data);
 185         return 0;
 186
 187 rtattr_failure:
 188         skb_trim(skb, (u8*)mx - skb->data);
 189         return -1;
 190 }
 191
 192
 193 static void set_operstate(struct net_device *dev, unsigned char transition)
 194 {
 195         unsigned char operstate = dev->operstate;
 196
 197         switch(transition) {
 198         case IF_OPER_UP:
 199                 if ((operstate == IF_OPER_DORMANT ||
 200                      operstate == IF_OPER_UNKNOWN) &&
 201                     !netif_dormant(dev))
 202                         operstate = IF_OPER_UP;
 203                 break;
 204
 205         case IF_OPER_DORMANT:
 206                 if (operstate == IF_OPER_UP ||
 207                     operstate == IF_OPER_UNKNOWN)
 208                         operstate = IF_OPER_DORMANT;
 209                 break;
 210         };
 211
 212         if (dev->operstate != operstate) {
 213                 write_lock_bh(&dev_base_lock);
 214                 dev->operstate = operstate;
 215                 write_unlock_bh(&dev_base_lock);
 216                 netdev_state_change(dev);
 217         }
 218 }
 219
 220 static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 221                                  int type, u32 pid, u32 seq, u32 change,
 222                                  unsigned int flags)
 223 {
 224         struct ifinfomsg *r;
 225         struct nlmsghdr  *nlh;
 226         unsigned char    *b = skb->tail;
 227
 228         nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*r), flags);
 229         r = NLMSG_DATA(nlh);
 230         r->ifi_family = AF_UNSPEC;
 231         r->__ifi_pad = 0;
 232         r->ifi_type = dev->type;
 233         r->ifi_index = dev->ifindex;
 234         r->ifi_flags = dev_get_flags(dev);
 235         r->ifi_change = change;
 236
 237         RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name);
 238
 239         if (1) {
 240                 u32 txqlen = dev->tx_queue_len;
 241                 RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen);
 242         }
 243
 244         if (1) {
 245                 u32 weight = dev->weight;
 246                 RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight);
 247         }
 248
 249         if (1) {
 250                 u8 operstate = netif_running(dev)?dev->operstate:IF_OPER_DOWN;
 251                 u8 link_mode = dev->link_mode;
 252                 RTA_PUT(skb, IFLA_OPERSTATE, sizeof(operstate), &operstate);
 253                 RTA_PUT(skb, IFLA_LINKMODE, sizeof(link_mode), &link_mode);
 254         }
 255
 256         if (1) {
 257                 struct rtnl_link_ifmap map = {
 258                         .mem_start   = dev->mem_start,
 259                         .mem_end     = dev->mem_end,
 260                         .base_addr   = dev->base_addr,
 261                         .irq         = dev->irq,
 262                         .dma         = dev->dma,
 263                         .port        = dev->if_port,
 264                 };
 265                 RTA_PUT(skb, IFLA_MAP, sizeof(map), &map);
 266         }
 267
 268         if (dev->addr_len) {
 269                 RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
 270                 RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
 271         }
 272
 273         if (1) {
 274                 u32 mtu = dev->mtu;
 275                 RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu);
 276         }
 277
 278         if (dev->ifindex != dev->iflink) {
 279                 u32 iflink = dev->iflink;
 280                 RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink);
 281         }
 282
 283         if (dev->qdisc_sleeping)
 284                 RTA_PUT(skb, IFLA_QDISC,
 285                         strlen(dev->qdisc_sleeping->ops->id) + 1,
 286                         dev->qdisc_sleeping->ops->id);
 287
 288         if (dev->master) {
 289                 u32 master = dev->master->ifindex;
 290                 RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master);
 291         }
 292
 293         if (dev->get_stats) {
 294                 unsigned long *stats = (unsigned long*)dev->get_stats(dev);
 295                 if (stats) {
 296                         struct rtattr  *a;
 297                         __u32          *s;
 298                         int             i;
 299                         int             n = sizeof(struct rtnl_link_stats)/4;
 300
 301                         a = __RTA_PUT(skb, IFLA_STATS, n*4);
 302                         s = RTA_DATA(a);
 303                         for (i=0; i<n; i++)
 304                                 s[i] = stats[i];
 305                 }
 306         }
 307         nlh->nlmsg_len = skb->tail - b;
 308         return skb->len;
 309
 310 nlmsg_failure:
 311 rtattr_failure:
 312         skb_trim(skb, b - skb->data);
 313         return -1;
 314 }
 315
 316 static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 317 {
 318         int idx;
 319         int s_idx = cb->args[0];
 320         struct net_device *dev;
 321
 322         read_lock(&dev_base_lock);
 323         for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
 324                 if (idx < s_idx)
 325                         continue;
 326                 if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK,
 327                                           NETLINK_CB(cb->skb).pid,
 328                                           cb->nlh->nlmsg_seq, 0,
 329                                           NLM_F_MULTI) <= 0)
 330                         break;
 331         }
 332         read_unlock(&dev_base_lock);
 333         cb->args[0] = idx;
 334
 335         return skb->len;
 336 }
 337
 338 static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 339 {
 340         struct ifinfomsg  *ifm = NLMSG_DATA(nlh);
 341         struct rtattr    **ida = arg;
 342         struct net_device *dev;
 343         int err, send_addr_notify = 0;
 344
 345         if (ifm->ifi_index >= 0)
 346                 dev = dev_get_by_index(ifm->ifi_index);
 347         else if (ida[IFLA_IFNAME - 1]) {
 348                 char ifname[IFNAMSIZ];
 349
 350                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
 351                                    IFNAMSIZ) >= IFNAMSIZ)
 352                         return -EINVAL;
 353                 dev = dev_get_by_name(ifname);
 354         } else
 355                 return -EINVAL;
 356
 357         if (!dev)
 358                 return -ENODEV;
 359
 360         err = -EINVAL;
 361
 362         if (ifm->ifi_flags)
 363                 dev_change_flags(dev, ifm->ifi_flags);
 364
 365         if (ida[IFLA_MAP - 1]) {
 366                 struct rtnl_link_ifmap *u_map;
 367                 struct ifmap k_map;
 368
 369                 if (!dev->set_config) {
 370                         err = -EOPNOTSUPP;
 371                         goto out;
 372                 }
 373
 374                 if (!netif_device_present(dev)) {
 375                         err = -ENODEV;
 376                         goto out;
 377                 }
 378
 379                 if (ida[IFLA_MAP - 1]->rta_len != RTA_LENGTH(sizeof(*u_map)))
 380                         goto out;
 381
 382                 u_map = RTA_DATA(ida[IFLA_MAP - 1]);
 383
 384                 k_map.mem_start = (unsigned long) u_map->mem_start;
 385                 k_map.mem_end = (unsigned long) u_map->mem_end;
 386                 k_map.base_addr = (unsigned short) u_map->base_addr;
 387                 k_map.irq = (unsigned char) u_map->irq;
 388                 k_map.dma = (unsigned char) u_map->dma;
 389                 k_map.port = (unsigned char) u_map->port;
 390
 391                 err = dev->set_config(dev, &k_map);
 392
 393                 if (err)
 394                         goto out;
 395         }
 396
 397         if (ida[IFLA_ADDRESS - 1]) {
 398                 if (!dev->set_mac_address) {
 399                         err = -EOPNOTSUPP;
 400                         goto out;
 401                 }
 402                 if (!netif_device_present(dev)) {
 403                         err = -ENODEV;
 404                         goto out;
 405                 }
 406                 if (ida[IFLA_ADDRESS - 1]->rta_len != RTA_LENGTH(dev->addr_len))
 407                         goto out;
 408
 409                 err = dev->set_mac_address(dev, RTA_DATA(ida[IFLA_ADDRESS - 1]));
 410                 if (err)
 411                         goto out;
 412                 send_addr_notify = 1;
 413         }
 414
 415         if (ida[IFLA_BROADCAST - 1]) {
 416                 if (ida[IFLA_BROADCAST - 1]->rta_len != RTA_LENGTH(dev->addr_len))
 417                         goto out;
 418                 memcpy(dev->broadcast, RTA_DATA(ida[IFLA_BROADCAST - 1]),
 419                        dev->addr_len);
 420                 send_addr_notify = 1;
 421         }
 422
 423         if (ida[IFLA_MTU - 1]) {
 424                 if (ida[IFLA_MTU - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 425                         goto out;
 426                 err = dev_set_mtu(dev, *((u32 *) RTA_DATA(ida[IFLA_MTU - 1])));
 427
 428                 if (err)
 429                         goto out;
 430
 431         }
 432
 433         if (ida[IFLA_TXQLEN - 1]) {
 434                 if (ida[IFLA_TXQLEN - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 435                         goto out;
 436
 437                 dev->tx_queue_len = *((u32 *) RTA_DATA(ida[IFLA_TXQLEN - 1]));
 438         }
 439
 440         if (ida[IFLA_WEIGHT - 1]) {
 441                 if (ida[IFLA_WEIGHT - 1]->rta_len != RTA_LENGTH(sizeof(u32)))
 442                         goto out;
 443
 444                 dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1]));
 445         }
 446
 447         if (ida[IFLA_OPERSTATE - 1]) {
 448                 if (ida[IFLA_OPERSTATE - 1]->rta_len != RTA_LENGTH(sizeof(u8)))
 449                         goto out;
 450
 451                 set_operstate(dev, *((u8 *) RTA_DATA(ida[IFLA_OPERSTATE - 1])));
 452         }
 453
 454         if (ida[IFLA_LINKMODE - 1]) {
 455                 if (ida[IFLA_LINKMODE - 1]->rta_len != RTA_LENGTH(sizeof(u8)))
 456                         goto out;
 457
 458                 write_lock_bh(&dev_base_lock);
 459                 dev->link_mode = *((u8 *) RTA_DATA(ida[IFLA_LINKMODE - 1]));
 460                 write_unlock_bh(&dev_base_lock);
 461         }
 462
 463         if (ifm->ifi_index >= 0 && ida[IFLA_IFNAME - 1]) {
 464                 char ifname[IFNAMSIZ];
 465
 466                 if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1],
 467                                    IFNAMSIZ) >= IFNAMSIZ)
 468                         goto out;
 469                 err = dev_change_name(dev, ifname);
 470                 if (err)
 471                         goto out;
 472         }
 473
 474 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 475         if (ida[IFLA_WIRELESS - 1]) {
 476
 477                 /* Call Wireless Extensions.
 478                  * Various stuff checked in there... */
 479                 err = wireless_rtnetlink_set(dev, RTA_DATA(ida[IFLA_WIRELESS - 1]), ida[IFLA_WIRELESS - 1]->rta_len);
 480                 if (err)
 481                         goto out;
 482         }
 483 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 484
 485         err = 0;
 486
 487 out:
 488         if (send_addr_notify)
 489                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 490
 491         dev_put(dev);
 492         return err;
 493 }
 494
 495 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 496 static int do_getlink(struct sk_buff *in_skb, struct nlmsghdr* in_nlh, void *arg)
 497 {
 498         struct ifinfomsg  *ifm = NLMSG_DATA(in_nlh);
 499         struct rtattr    **ida = arg;
 500         struct net_device *dev;
 501         struct ifinfomsg *r;
 502         struct nlmsghdr  *nlh;
 503         int err = -ENOBUFS;
 504         struct sk_buff *skb;
 505         unsigned char    *b;
 506         char *iw_buf = NULL;
 507         int iw_buf_len = 0;
 508
 509         if (ifm->ifi_index >= 0)
 510                 dev = dev_get_by_index(ifm->ifi_index);
 511         else
 512                 return -EINVAL;
 513         if (!dev)
 514                 return -ENODEV;
 515
 516 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 517         if (ida[IFLA_WIRELESS - 1]) {
 518
 519                 /* Call Wireless Extensions. We need to know the size before
 520                  * we can alloc. Various stuff checked in there... */
 521                 err = wireless_rtnetlink_get(dev, RTA_DATA(ida[IFLA_WIRELESS - 1]), ida[IFLA_WIRELESS - 1]->rta_len, &iw_buf, &iw_buf_len);
 522                 if (err)
 523                         goto out;
 524         }
 525 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 526
 527         /* Create a skb big enough to include all the data.
 528          * Some requests are way bigger than 4k... Jean II */
 529         skb = alloc_skb((NLMSG_LENGTH(sizeof(*r))) + (RTA_SPACE(iw_buf_len)),
 530                         GFP_KERNEL);
 531         if (!skb)
 532                 goto out;
 533         b = skb->tail;
 534
 535         /* Put in the message the usual good stuff */
 536         nlh = NLMSG_PUT(skb, NETLINK_CB(in_skb).pid, in_nlh->nlmsg_seq,
 537                         RTM_NEWLINK, sizeof(*r));
 538         r = NLMSG_DATA(nlh);
 539         r->ifi_family = AF_UNSPEC;
 540         r->__ifi_pad = 0;
 541         r->ifi_type = dev->type;
 542         r->ifi_index = dev->ifindex;
 543         r->ifi_flags = dev->flags;
 544         r->ifi_change = 0;
 545
 546         /* Put the wireless payload if it exist */
 547         if(iw_buf != NULL)
 548                 RTA_PUT(skb, IFLA_WIRELESS, iw_buf_len,
 549                         iw_buf + IW_EV_POINT_OFF);
 550
 551         nlh->nlmsg_len = skb->tail - b;
 552
 553         /* Needed ? */
 554         NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
 555
 556         err = netlink_unicast(rtnl, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
 557         if (err > 0)
 558                 err = 0;
 559 out:
 560         if(iw_buf != NULL)
 561                 kfree(iw_buf);
 562         dev_put(dev);
 563         return err;
 564
 565 rtattr_failure:
 566 nlmsg_failure:
 567         kfree_skb(skb);
 568         goto out;
 569 }
 570 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 571
 572 static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 573 {
 574         int idx;
 575         int s_idx = cb->family;
 576
 577         if (s_idx == 0)
 578                 s_idx = 1;
 579         for (idx=1; idx<NPROTO; idx++) {
 580                 int type = cb->nlh->nlmsg_type-RTM_BASE;
 581                 if (idx < s_idx || idx == PF_PACKET)
 582                         continue;
 583                 if (rtnetlink_links[idx] == NULL ||
 584                     rtnetlink_links[idx][type].dumpit == NULL)
 585                         continue;
 586                 if (idx > s_idx)
 587                         memset(&cb->args[0], 0, sizeof(cb->args));
 588                 if (rtnetlink_links[idx][type].dumpit(skb, cb))
 589                         break;
 590         }
 591         cb->family = idx;
 592
 593         return skb->len;
 594 }
 595
 596 void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
 597 {
 598         struct sk_buff *skb;
 599         int size = NLMSG_SPACE(sizeof(struct ifinfomsg) +
 600                                sizeof(struct rtnl_link_ifmap) +
 601                                sizeof(struct rtnl_link_stats) + 128);
 602
 603         skb = alloc_skb(size, GFP_KERNEL);
 604         if (!skb)
 605                 return;
 606
 607         if (rtnetlink_fill_ifinfo(skb, dev, type, 0, 0, change, 0) < 0) {
 608                 kfree_skb(skb);
 609                 return;
 610         }
 611         NETLINK_CB(skb).dst_group = RTNLGRP_LINK;
 612         netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL);
 613 }
 614
 615 /* Protected by RTNL sempahore.  */
 616 static struct rtattr **rta_buf;
 617 static int rtattr_max;
 618
 619 /* Process one rtnetlink message. */
 620
 621 static __inline__ int
 622 rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 623 {
 624         struct rtnetlink_link *link;
 625         struct rtnetlink_link *link_tab;
 626         int sz_idx, kind;
 627         int min_len;
 628         int family;
 629         int type;
 630         int err;
 631
 632         /* Only requests are handled by kernel now */
 633         if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
 634                 return 0;
 635
 636         type = nlh->nlmsg_type;
 637
 638         /* A control message: ignore them */
 639         if (type < RTM_BASE)
 640                 return 0;
 641
 642         /* Unknown message: reply with EINVAL */
 643         if (type > RTM_MAX)
 644                 goto err_inval;
 645
 646         type -= RTM_BASE;
 647
 648         /* All the messages must have at least 1 byte length */
 649         if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
 650                 return 0;
 651
 652         family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
 653         if (family >= NPROTO) {
 654                 *errp = -EAFNOSUPPORT;
 655                 return -1;
 656         }
 657
 658         link_tab = rtnetlink_links[family];
 659         if (link_tab == NULL)
 660                 link_tab = rtnetlink_links[PF_UNSPEC];
 661         link = &link_tab[type];
 662
 663         sz_idx = type>>2;
 664         kind = type&3;
 665
 666         if (kind != 2 && security_netlink_recv(skb)) {
 667                 *errp = -EPERM;
 668                 return -1;
 669         }
 670
 671         if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
 672                 if (link->dumpit == NULL)
 673                         link = &(rtnetlink_links[PF_UNSPEC][type]);
 674
 675                 if (link->dumpit == NULL)
 676                         goto err_inval;
 677
 678                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
 679                                                 link->dumpit, NULL)) != 0) {
 680                         return -1;
 681                 }
 682
 683                 netlink_queue_skip(nlh, skb);
 684                 return -1;
 685         }
 686
 687         memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
 688
 689         min_len = rtm_min[sz_idx];
 690         if (nlh->nlmsg_len < min_len)
 691                 goto err_inval;
 692
 693         if (nlh->nlmsg_len > min_len) {
 694                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
 695                 struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
 696
 697                 while (RTA_OK(attr, attrlen)) {
 698                         unsigned flavor = attr->rta_type;
 699                         if (flavor) {
 700                                 if (flavor > rta_max[sz_idx])
 701                                         goto err_inval;
 702                                 rta_buf[flavor-1] = attr;
 703                         }
 704                         attr = RTA_NEXT(attr, attrlen);
 705                 }
 706         }
 707
 708         if (link->doit == NULL)
 709                 link = &(rtnetlink_links[PF_UNSPEC][type]);
 710         if (link->doit == NULL)
 711                 goto err_inval;
 712         err = link->doit(skb, nlh, (void *)&rta_buf[0]);
 713
 714         *errp = err;
 715         return err;
 716
 717 err_inval:
 718         *errp = -EINVAL;
 719         return -1;
 720 }
 721
 722 static void rtnetlink_rcv(struct sock *sk, int len)
 723 {
 724         unsigned int qlen = 0;
 725
 726         do {
 727                 mutex_lock(&rtnl_mutex);
 728                 netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
 729                 mutex_unlock(&rtnl_mutex);
 730
 731                 netdev_run_todo();
 732         } while (qlen);
 733 }
 734
 735 static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] =
 736 {
 737         [RTM_GETLINK     - RTM_BASE] = {
 738 #ifdef CONFIG_NET_WIRELESS_RTNETLINK
 739                                          .doit   = do_getlink,
 740 #endif  /* CONFIG_NET_WIRELESS_RTNETLINK */
 741                                          .dumpit = rtnetlink_dump_ifinfo },
 742         [RTM_SETLINK     - RTM_BASE] = { .doit   = do_setlink            },
 743         [RTM_GETADDR     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 744         [RTM_GETROUTE    - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 745         [RTM_NEWNEIGH    - RTM_BASE] = { .doit   = neigh_add             },
 746         [RTM_DELNEIGH    - RTM_BASE] = { .doit   = neigh_delete          },
 747         [RTM_GETNEIGH    - RTM_BASE] = { .dumpit = neigh_dump_info       },
 748         [RTM_GETRULE     - RTM_BASE] = { .dumpit = rtnetlink_dump_all    },
 749         [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info    },
 750         [RTM_SETNEIGHTBL - RTM_BASE] = { .doit   = neightbl_set          },
 751 };
 752
 753 static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
 754 {
 755         struct net_device *dev = ptr;
 756         switch (event) {
 757         case NETDEV_UNREGISTER:
 758                 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
 759                 break;
 760         case NETDEV_REGISTER:
 761                 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
 762                 break;
 763         case NETDEV_UP:
 764         case NETDEV_DOWN:
 765                 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
 766                 break;
 767         case NETDEV_CHANGE:
 768         case NETDEV_GOING_DOWN:
 769                 break;
 770         default:
 771                 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
 772                 break;
 773         }
 774         return NOTIFY_DONE;
 775 }
 776
 777 static struct notifier_block rtnetlink_dev_notifier = {
 778         .notifier_call  = rtnetlink_event,
 779 };
 780
 781 void __init rtnetlink_init(void)
 782 {
 783         int i;
 784
 785         rtattr_max = 0;
 786         for (i = 0; i < ARRAY_SIZE(rta_max); i++)
 787                 if (rta_max[i] > rtattr_max)
 788                         rtattr_max = rta_max[i];
 789         rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
 790         if (!rta_buf)
 791                 panic("rtnetlink_init: cannot allocate rta_buf\n");
 792
 793         rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
 794                                      THIS_MODULE);
 795         if (rtnl == NULL)
 796                 panic("rtnetlink_init: cannot initialize rtnetlink\n");
 797         netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
 798         register_netdevice_notifier(&rtnetlink_dev_notifier);
 799         rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table;
 800         rtnetlink_links[PF_PACKET] = link_rtnetlink_table;
 801 }
 802
 803 EXPORT_SYMBOL(__rta_fill);
 804 EXPORT_SYMBOL(rtattr_strlcpy);
 805 EXPORT_SYMBOL(rtattr_parse);
 806 EXPORT_SYMBOL(rtnetlink_links);
 807 EXPORT_SYMBOL(rtnetlink_put_metrics);
 808 EXPORT_SYMBOL(rtnl);
 809 EXPORT_SYMBOL(rtnl_lock);
 810 EXPORT_SYMBOL(rtnl_trylock);
 811 EXPORT_SYMBOL(rtnl_unlock);