net/ipv4/fib_frontend.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  *              IPv4 Forwarding Information Base: FIB frontend.
   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
  16 #include <linux/module.h>
  17 #include <asm/uaccess.h>
  18 #include <linux/bitops.h>
  19 #include <linux/capability.h>
  20 #include <linux/types.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/string.h>
  24 #include <linux/socket.h>
  25 #include <linux/sockios.h>
  26 #include <linux/errno.h>
  27 #include <linux/in.h>
  28 #include <linux/inet.h>
  29 #include <linux/inetdevice.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/if_addr.h>
  32 #include <linux/if_arp.h>
  33 #include <linux/skbuff.h>
  34 #include <linux/cache.h>
  35 #include <linux/init.h>
  36 #include <linux/list.h>
  37 #include <linux/slab.h>
  38
  39 #include <net/ip.h>
  40 #include <net/protocol.h>
  41 #include <net/route.h>
  42 #include <net/tcp.h>
  43 #include <net/sock.h>
  44 #include <net/arp.h>
  45 #include <net/ip_fib.h>
  46 #include <net/rtnetlink.h>
  47 #include <net/xfrm.h>
  48 #include <net/l3mdev.h>
  49 #include <trace/events/fib.h>
  50
  51 #ifndef CONFIG_IP_MULTIPLE_TABLES
  52
  53 static int __net_init fib4_rules_init(struct net *net)
  54 {
  55         struct fib_table *local_table, *main_table;
  56
  57         main_table  = fib_trie_table(RT_TABLE_MAIN, NULL);
  58         if (!main_table)
  59                 return -ENOMEM;
  60
  61         local_table = fib_trie_table(RT_TABLE_LOCAL, main_table);
  62         if (!local_table)
  63                 goto fail;
  64
  65         hlist_add_head_rcu(&local_table->tb_hlist,
  66                                 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
  67         hlist_add_head_rcu(&main_table->tb_hlist,
  68                                 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
  69         return 0;
  70
  71 fail:
  72         fib_free_table(main_table);
  73         return -ENOMEM;
  74 }
  75 #else
  76
  77 struct fib_table *fib_new_table(struct net *net, u32 id)
  78 {
  79         struct fib_table *tb, *alias = NULL;
  80         unsigned int h;
  81
  82         if (id == 0)
  83                 id = RT_TABLE_MAIN;
  84         tb = fib_get_table(net, id);
  85         if (tb)
  86                 return tb;
  87
  88         if (id == RT_TABLE_LOCAL)
  89                 alias = fib_new_table(net, RT_TABLE_MAIN);
  90
  91         tb = fib_trie_table(id, alias);
  92         if (!tb)
  93                 return NULL;
  94
  95         switch (id) {
  96         case RT_TABLE_MAIN:
  97                 rcu_assign_pointer(net->ipv4.fib_main, tb);
  98                 break;
  99         case RT_TABLE_DEFAULT:
 100                 rcu_assign_pointer(net->ipv4.fib_default, tb);
 101                 break;
 102         default:
 103                 break;
 104         }
 105
 106         h = id & (FIB_TABLE_HASHSZ - 1);
 107         hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
 108         return tb;
 109 }
 110 EXPORT_SYMBOL_GPL(fib_new_table);
 111
 112 /* caller must hold either rtnl or rcu read lock */
 113 struct fib_table *fib_get_table(struct net *net, u32 id)
 114 {
 115         struct fib_table *tb;
 116         struct hlist_head *head;
 117         unsigned int h;
 118
 119         if (id == 0)
 120                 id = RT_TABLE_MAIN;
 121         h = id & (FIB_TABLE_HASHSZ - 1);
 122
 123         head = &net->ipv4.fib_table_hash[h];
 124         hlist_for_each_entry_rcu(tb, head, tb_hlist) {
 125                 if (tb->tb_id == id)
 126                         return tb;
 127         }
 128         return NULL;
 129 }
 130 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 131
 132 static void fib_replace_table(struct net *net, struct fib_table *old,
 133                               struct fib_table *new)
 134 {
 135 #ifdef CONFIG_IP_MULTIPLE_TABLES
 136         switch (new->tb_id) {
 137         case RT_TABLE_MAIN:
 138                 rcu_assign_pointer(net->ipv4.fib_main, new);
 139                 break;
 140         case RT_TABLE_DEFAULT:
 141                 rcu_assign_pointer(net->ipv4.fib_default, new);
 142                 break;
 143         default:
 144                 break;
 145         }
 146
 147 #endif
 148         /* replace the old table in the hlist */
 149         hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist);
 150 }
 151
 152 int fib_unmerge(struct net *net)
 153 {
 154         struct fib_table *old, *new;
 155
 156         /* attempt to fetch local table if it has been allocated */
 157         old = fib_get_table(net, RT_TABLE_LOCAL);
 158         if (!old)
 159                 return 0;
 160
 161         new = fib_trie_unmerge(old);
 162         if (!new)
 163                 return -ENOMEM;
 164
 165         /* replace merged table with clean table */
 166         if (new != old) {
 167                 fib_replace_table(net, old, new);
 168                 fib_free_table(old);
 169         }
 170
 171         return 0;
 172 }
 173
 174 static void fib_flush(struct net *net)
 175 {
 176         int flushed = 0;
 177         unsigned int h;
 178
 179         for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
 180                 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
 181                 struct hlist_node *tmp;
 182                 struct fib_table *tb;
 183
 184                 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist)
 185                         flushed += fib_table_flush(net, tb);
 186         }
 187
 188         if (flushed)
 189                 rt_cache_flush(net);
 190 }
 191
 192 /*
 193  * Find address type as if only "dev" was present in the system. If
 194  * on_dev is NULL then all interfaces are taken into consideration.
 195  */
 196 static inline unsigned int __inet_dev_addr_type(struct net *net,
 197                                                 const struct net_device *dev,
 198                                                 __be32 addr, u32 tb_id)
 199 {
 200         struct flowi4           fl4 = { .daddr = addr };
 201         struct fib_result       res;
 202         unsigned int ret = RTN_BROADCAST;
 203         struct fib_table *table;
 204
 205         if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
 206                 return RTN_BROADCAST;
 207         if (ipv4_is_multicast(addr))
 208                 return RTN_MULTICAST;
 209
 210         rcu_read_lock();
 211
 212         table = fib_get_table(net, tb_id);
 213         if (table) {
 214                 ret = RTN_UNICAST;
 215                 if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) {
 216                         if (!dev || dev == res.fi->fib_dev)
 217                                 ret = res.type;
 218                 }
 219         }
 220
 221         rcu_read_unlock();
 222         return ret;
 223 }
 224
 225 unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id)
 226 {
 227         return __inet_dev_addr_type(net, NULL, addr, tb_id);
 228 }
 229 EXPORT_SYMBOL(inet_addr_type_table);
 230
 231 unsigned int inet_addr_type(struct net *net, __be32 addr)
 232 {
 233         return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL);
 234 }
 235 EXPORT_SYMBOL(inet_addr_type);
 236
 237 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
 238                                 __be32 addr)
 239 {
 240         u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
 241
 242         return __inet_dev_addr_type(net, dev, addr, rt_table);
 243 }
 244 EXPORT_SYMBOL(inet_dev_addr_type);
 245
 246 /* inet_addr_type with dev == NULL but using the table from a dev
 247  * if one is associated
 248  */
 249 unsigned int inet_addr_type_dev_table(struct net *net,
 250                                       const struct net_device *dev,
 251                                       __be32 addr)
 252 {
 253         u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
 254
 255         return __inet_dev_addr_type(net, NULL, addr, rt_table);
 256 }
 257 EXPORT_SYMBOL(inet_addr_type_dev_table);
 258
 259 __be32 fib_compute_spec_dst(struct sk_buff *skb)
 260 {
 261         struct net_device *dev = skb->dev;
 262         struct in_device *in_dev;
 263         struct fib_result res;
 264         struct rtable *rt;
 265         struct net *net;
 266         int scope;
 267
 268         rt = skb_rtable(skb);
 269         if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) ==
 270             RTCF_LOCAL)
 271                 return ip_hdr(skb)->daddr;
 272
 273         in_dev = __in_dev_get_rcu(dev);
 274         BUG_ON(!in_dev);
 275
 276         net = dev_net(dev);
 277
 278         scope = RT_SCOPE_UNIVERSE;
 279         if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
 280                 struct flowi4 fl4 = {
 281                         .flowi4_iif = LOOPBACK_IFINDEX,
 282                         .daddr = ip_hdr(skb)->saddr,
 283                         .flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
 284                         .flowi4_scope = scope,
 285                         .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0,
 286                 };
 287                 if (!fib_lookup(net, &fl4, &res, 0))
 288                         return FIB_RES_PREFSRC(net, res);
 289         } else {
 290                 scope = RT_SCOPE_LINK;
 291         }
 292
 293         return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
 294 }
 295
 296 /* Given (packet source, input interface) and optional (dst, oif, tos):
 297  * - (main) check, that source is valid i.e. not broadcast or our local
 298  *   address.
 299  * - figure out what "logical" interface this packet arrived
 300  *   and calculate "specific destination" address.
 301  * - check, that packet arrived from expected physical interface.
 302  * called with rcu_read_lock()
 303  */
 304 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
 305                                  u8 tos, int oif, struct net_device *dev,
 306                                  int rpf, struct in_device *idev, u32 *itag)
 307 {
 308         int ret, no_addr;
 309         struct fib_result res;
 310         struct flowi4 fl4;
 311         struct net *net;
 312         bool dev_match;
 313
 314         fl4.flowi4_oif = 0;
 315         fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev);
 316         if (!fl4.flowi4_iif)
 317                 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX;
 318         fl4.daddr = src;
 319         fl4.saddr = dst;
 320         fl4.flowi4_tos = tos;
 321         fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
 322         fl4.flowi4_tun_key.tun_id = 0;
 323         fl4.flowi4_flags = 0;
 324
 325         no_addr = idev->ifa_list == NULL;
 326
 327         fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0;
 328
 329         trace_fib_validate_source(dev, &fl4);
 330
 331         net = dev_net(dev);
 332         if (fib_lookup(net, &fl4, &res, 0))
 333                 goto last_resort;
 334         if (res.type != RTN_UNICAST &&
 335             (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev)))
 336                 goto e_inval;
 337         if (!rpf && !fib_num_tclassid_users(dev_net(dev)) &&
 338             (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev)))
 339                 goto last_resort;
 340         fib_combine_itag(itag, &res);
 341         dev_match = false;
 342
 343 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 344         for (ret = 0; ret < res.fi->fib_nhs; ret++) {
 345                 struct fib_nh *nh = &res.fi->fib_nh[ret];
 346
 347                 if (nh->nh_dev == dev) {
 348                         dev_match = true;
 349                         break;
 350                 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
 351                         dev_match = true;
 352                         break;
 353                 }
 354         }
 355 #else
 356         if (FIB_RES_DEV(res) == dev)
 357                 dev_match = true;
 358 #endif
 359         if (dev_match) {
 360                 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
 361                 return ret;
 362         }
 363         if (no_addr)
 364                 goto last_resort;
 365         if (rpf == 1)
 366                 goto e_rpf;
 367         fl4.flowi4_oif = dev->ifindex;
 368
 369         ret = 0;
 370         if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
 371                 if (res.type == RTN_UNICAST)
 372                         ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
 373         }
 374         return ret;
 375
 376 last_resort:
 377         if (rpf)
 378                 goto e_rpf;
 379         *itag = 0;
 380         return 0;
 381
 382 e_inval:
 383         return -EINVAL;
 384 e_rpf:
 385         return -EXDEV;
 386 }
 387
 388 /* Ignore rp_filter for packets protected by IPsec. */
 389 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
 390                         u8 tos, int oif, struct net_device *dev,
 391                         struct in_device *idev, u32 *itag)
 392 {
 393         int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
 394
 395         if (!r && !fib_num_tclassid_users(dev_net(dev)) &&
 396             IN_DEV_ACCEPT_LOCAL(idev) &&
 397             (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
 398                 *itag = 0;
 399                 return 0;
 400         }
 401         return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag);
 402 }
 403
 404 static inline __be32 sk_extract_addr(struct sockaddr *addr)
 405 {
 406         return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
 407 }
 408
 409 static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
 410 {
 411         struct nlattr *nla;
 412
 413         nla = (struct nlattr *) ((char *) mx + len);
 414         nla->nla_type = type;
 415         nla->nla_len = nla_attr_size(4);
 416         *(u32 *) nla_data(nla) = value;
 417
 418         return len + nla_total_size(4);
 419 }
 420
 421 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
 422                                  struct fib_config *cfg)
 423 {
 424         __be32 addr;
 425         int plen;
 426
 427         memset(cfg, 0, sizeof(*cfg));
 428         cfg->fc_nlinfo.nl_net = net;
 429
 430         if (rt->rt_dst.sa_family != AF_INET)
 431                 return -EAFNOSUPPORT;
 432
 433         /*
 434          * Check mask for validity:
 435          * a) it must be contiguous.
 436          * b) destination must have all host bits clear.
 437          * c) if application forgot to set correct family (AF_INET),
 438          *    reject request unless it is absolutely clear i.e.
 439          *    both family and mask are zero.
 440          */
 441         plen = 32;
 442         addr = sk_extract_addr(&rt->rt_dst);
 443         if (!(rt->rt_flags & RTF_HOST)) {
 444                 __be32 mask = sk_extract_addr(&rt->rt_genmask);
 445
 446                 if (rt->rt_genmask.sa_family != AF_INET) {
 447                         if (mask || rt->rt_genmask.sa_family)
 448                                 return -EAFNOSUPPORT;
 449                 }
 450
 451                 if (bad_mask(mask, addr))
 452                         return -EINVAL;
 453
 454                 plen = inet_mask_len(mask);
 455         }
 456
 457         cfg->fc_dst_len = plen;
 458         cfg->fc_dst = addr;
 459
 460         if (cmd != SIOCDELRT) {
 461                 cfg->fc_nlflags = NLM_F_CREATE;
 462                 cfg->fc_protocol = RTPROT_BOOT;
 463         }
 464
 465         if (rt->rt_metric)
 466                 cfg->fc_priority = rt->rt_metric - 1;
 467
 468         if (rt->rt_flags & RTF_REJECT) {
 469                 cfg->fc_scope = RT_SCOPE_HOST;
 470                 cfg->fc_type = RTN_UNREACHABLE;
 471                 return 0;
 472         }
 473
 474         cfg->fc_scope = RT_SCOPE_NOWHERE;
 475         cfg->fc_type = RTN_UNICAST;
 476
 477         if (rt->rt_dev) {
 478                 char *colon;
 479                 struct net_device *dev;
 480                 char devname[IFNAMSIZ];
 481
 482                 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
 483                         return -EFAULT;
 484
 485                 devname[IFNAMSIZ-1] = 0;
 486                 colon = strchr(devname, ':');
 487                 if (colon)
 488                         *colon = 0;
 489                 dev = __dev_get_by_name(net, devname);
 490                 if (!dev)
 491                         return -ENODEV;
 492                 cfg->fc_oif = dev->ifindex;
 493                 cfg->fc_table = l3mdev_fib_table(dev);
 494                 if (colon) {
 495                         struct in_ifaddr *ifa;
 496                         struct in_device *in_dev = __in_dev_get_rtnl(dev);
 497                         if (!in_dev)
 498                                 return -ENODEV;
 499                         *colon = ':';
 500                         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
 501                                 if (strcmp(ifa->ifa_label, devname) == 0)
 502                                         break;
 503                         if (!ifa)
 504                                 return -ENODEV;
 505                         cfg->fc_prefsrc = ifa->ifa_local;
 506                 }
 507         }
 508
 509         addr = sk_extract_addr(&rt->rt_gateway);
 510         if (rt->rt_gateway.sa_family == AF_INET && addr) {
 511                 unsigned int addr_type;
 512
 513                 cfg->fc_gw = addr;
 514                 addr_type = inet_addr_type_table(net, addr, cfg->fc_table);
 515                 if (rt->rt_flags & RTF_GATEWAY &&
 516                     addr_type == RTN_UNICAST)
 517                         cfg->fc_scope = RT_SCOPE_UNIVERSE;
 518         }
 519
 520         if (cmd == SIOCDELRT)
 521                 return 0;
 522
 523         if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
 524                 return -EINVAL;
 525
 526         if (cfg->fc_scope == RT_SCOPE_NOWHERE)
 527                 cfg->fc_scope = RT_SCOPE_LINK;
 528
 529         if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
 530                 struct nlattr *mx;
 531                 int len = 0;
 532
 533                 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
 534                 if (!mx)
 535                         return -ENOMEM;
 536
 537                 if (rt->rt_flags & RTF_MTU)
 538                         len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
 539
 540                 if (rt->rt_flags & RTF_WINDOW)
 541                         len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
 542
 543                 if (rt->rt_flags & RTF_IRTT)
 544                         len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
 545
 546                 cfg->fc_mx = mx;
 547                 cfg->fc_mx_len = len;
 548         }
 549
 550         return 0;
 551 }
 552
 553 /*
 554  * Handle IP routing ioctl calls.
 555  * These are used to manipulate the routing tables
 556  */
 557 int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 558 {
 559         struct fib_config cfg;
 560         struct rtentry rt;
 561         int err;
 562
 563         switch (cmd) {
 564         case SIOCADDRT:         /* Add a route */
 565         case SIOCDELRT:         /* Delete a route */
 566                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 567                         return -EPERM;
 568
 569                 if (copy_from_user(&rt, arg, sizeof(rt)))
 570                         return -EFAULT;
 571
 572                 rtnl_lock();
 573                 err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
 574                 if (err == 0) {
 575                         struct fib_table *tb;
 576
 577                         if (cmd == SIOCDELRT) {
 578                                 tb = fib_get_table(net, cfg.fc_table);
 579                                 if (tb)
 580                                         err = fib_table_delete(net, tb, &cfg);
 581                                 else
 582                                         err = -ESRCH;
 583                         } else {
 584                                 tb = fib_new_table(net, cfg.fc_table);
 585                                 if (tb)
 586                                         err = fib_table_insert(net, tb, &cfg);
 587                                 else
 588                                         err = -ENOBUFS;
 589                         }
 590
 591                         /* allocated by rtentry_to_fib_config() */
 592                         kfree(cfg.fc_mx);
 593                 }
 594                 rtnl_unlock();
 595                 return err;
 596         }
 597         return -EINVAL;
 598 }
 599
 600 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
 601         [RTA_DST]               = { .type = NLA_U32 },
 602         [RTA_SRC]               = { .type = NLA_U32 },
 603         [RTA_IIF]               = { .type = NLA_U32 },
 604         [RTA_OIF]               = { .type = NLA_U32 },
 605         [RTA_GATEWAY]           = { .type = NLA_U32 },
 606         [RTA_PRIORITY]          = { .type = NLA_U32 },
 607         [RTA_PREFSRC]           = { .type = NLA_U32 },
 608         [RTA_METRICS]           = { .type = NLA_NESTED },
 609         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
 610         [RTA_FLOW]              = { .type = NLA_U32 },
 611         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
 612         [RTA_ENCAP]             = { .type = NLA_NESTED },
 613 };
 614
 615 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 616                              struct nlmsghdr *nlh, struct fib_config *cfg)
 617 {
 618         struct nlattr *attr;
 619         int err, remaining;
 620         struct rtmsg *rtm;
 621
 622         err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
 623         if (err < 0)
 624                 goto errout;
 625
 626         memset(cfg, 0, sizeof(*cfg));
 627
 628         rtm = nlmsg_data(nlh);
 629         cfg->fc_dst_len = rtm->rtm_dst_len;
 630         cfg->fc_tos = rtm->rtm_tos;
 631         cfg->fc_table = rtm->rtm_table;
 632         cfg->fc_protocol = rtm->rtm_protocol;
 633         cfg->fc_scope = rtm->rtm_scope;
 634         cfg->fc_type = rtm->rtm_type;
 635         cfg->fc_flags = rtm->rtm_flags;
 636         cfg->fc_nlflags = nlh->nlmsg_flags;
 637
 638         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
 639         cfg->fc_nlinfo.nlh = nlh;
 640         cfg->fc_nlinfo.nl_net = net;
 641
 642         if (cfg->fc_type > RTN_MAX) {
 643                 err = -EINVAL;
 644                 goto errout;
 645         }
 646
 647         nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
 648                 switch (nla_type(attr)) {
 649                 case RTA_DST:
 650                         cfg->fc_dst = nla_get_be32(attr);
 651                         break;
 652                 case RTA_OIF:
 653                         cfg->fc_oif = nla_get_u32(attr);
 654                         break;
 655                 case RTA_GATEWAY:
 656                         cfg->fc_gw = nla_get_be32(attr);
 657                         break;
 658                 case RTA_PRIORITY:
 659                         cfg->fc_priority = nla_get_u32(attr);
 660                         break;
 661                 case RTA_PREFSRC:
 662                         cfg->fc_prefsrc = nla_get_be32(attr);
 663                         break;
 664                 case RTA_METRICS:
 665                         cfg->fc_mx = nla_data(attr);
 666                         cfg->fc_mx_len = nla_len(attr);
 667                         break;
 668                 case RTA_MULTIPATH:
 669                         cfg->fc_mp = nla_data(attr);
 670                         cfg->fc_mp_len = nla_len(attr);
 671                         break;
 672                 case RTA_FLOW:
 673                         cfg->fc_flow = nla_get_u32(attr);
 674                         break;
 675                 case RTA_TABLE:
 676                         cfg->fc_table = nla_get_u32(attr);
 677                         break;
 678                 case RTA_ENCAP:
 679                         cfg->fc_encap = attr;
 680                         break;
 681                 case RTA_ENCAP_TYPE:
 682                         cfg->fc_encap_type = nla_get_u16(attr);
 683                         break;
 684                 }
 685         }
 686
 687         return 0;
 688 errout:
 689         return err;
 690 }
 691
 692 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 693 {
 694         struct net *net = sock_net(skb->sk);
 695         struct fib_config cfg;
 696         struct fib_table *tb;
 697         int err;
 698
 699         err = rtm_to_fib_config(net, skb, nlh, &cfg);
 700         if (err < 0)
 701                 goto errout;
 702
 703         tb = fib_get_table(net, cfg.fc_table);
 704         if (!tb) {
 705                 err = -ESRCH;
 706                 goto errout;
 707         }
 708
 709         err = fib_table_delete(net, tb, &cfg);
 710 errout:
 711         return err;
 712 }
 713
 714 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
 715 {
 716         struct net *net = sock_net(skb->sk);
 717         struct fib_config cfg;
 718         struct fib_table *tb;
 719         int err;
 720
 721         err = rtm_to_fib_config(net, skb, nlh, &cfg);
 722         if (err < 0)
 723                 goto errout;
 724
 725         tb = fib_new_table(net, cfg.fc_table);
 726         if (!tb) {
 727                 err = -ENOBUFS;
 728                 goto errout;
 729         }
 730
 731         err = fib_table_insert(net, tb, &cfg);
 732 errout:
 733         return err;
 734 }
 735
 736 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 737 {
 738         struct net *net = sock_net(skb->sk);
 739         unsigned int h, s_h;
 740         unsigned int e = 0, s_e;
 741         struct fib_table *tb;
 742         struct hlist_head *head;
 743         int dumped = 0;
 744
 745         if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
 746             ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
 747                 return skb->len;
 748
 749         s_h = cb->args[0];
 750         s_e = cb->args[1];
 751
 752         rcu_read_lock();
 753
 754         for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
 755                 e = 0;
 756                 head = &net->ipv4.fib_table_hash[h];
 757                 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
 758                         if (e < s_e)
 759                                 goto next;
 760                         if (dumped)
 761                                 memset(&cb->args[2], 0, sizeof(cb->args) -
 762                                                  2 * sizeof(cb->args[0]));
 763                         if (fib_table_dump(tb, skb, cb) < 0)
 764                                 goto out;
 765                         dumped = 1;
 766 next:
 767                         e++;
 768                 }
 769         }
 770 out:
 771         rcu_read_unlock();
 772
 773         cb->args[1] = e;
 774         cb->args[0] = h;
 775
 776         return skb->len;
 777 }
 778
 779 /* Prepare and feed intra-kernel routing request.
 780  * Really, it should be netlink message, but :-( netlink
 781  * can be not configured, so that we feed it directly
 782  * to fib engine. It is legal, because all events occur
 783  * only when netlink is already locked.
 784  */
 785 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
 786 {
 787         struct net *net = dev_net(ifa->ifa_dev->dev);
 788         u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev);
 789         struct fib_table *tb;
 790         struct fib_config cfg = {
 791                 .fc_protocol = RTPROT_KERNEL,
 792                 .fc_type = type,
 793                 .fc_dst = dst,
 794                 .fc_dst_len = dst_len,
 795                 .fc_prefsrc = ifa->ifa_local,
 796                 .fc_oif = ifa->ifa_dev->dev->ifindex,
 797                 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
 798                 .fc_nlinfo = {
 799                         .nl_net = net,
 800                 },
 801         };
 802
 803         if (!tb_id)
 804                 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL;
 805
 806         tb = fib_new_table(net, tb_id);
 807         if (!tb)
 808                 return;
 809
 810         cfg.fc_table = tb->tb_id;
 811
 812         if (type != RTN_LOCAL)
 813                 cfg.fc_scope = RT_SCOPE_LINK;
 814         else
 815                 cfg.fc_scope = RT_SCOPE_HOST;
 816
 817         if (cmd == RTM_NEWROUTE)
 818                 fib_table_insert(net, tb, &cfg);
 819         else
 820                 fib_table_delete(net, tb, &cfg);
 821 }
 822
 823 void fib_add_ifaddr(struct in_ifaddr *ifa)
 824 {
 825         struct in_device *in_dev = ifa->ifa_dev;
 826         struct net_device *dev = in_dev->dev;
 827         struct in_ifaddr *prim = ifa;
 828         __be32 mask = ifa->ifa_mask;
 829         __be32 addr = ifa->ifa_local;
 830         __be32 prefix = ifa->ifa_address & mask;
 831
 832         if (ifa->ifa_flags & IFA_F_SECONDARY) {
 833                 prim = inet_ifa_byprefix(in_dev, prefix, mask);
 834                 if (!prim) {
 835                         pr_warn("%s: bug: prim == NULL\n", __func__);
 836                         return;
 837                 }
 838         }
 839
 840         fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
 841
 842         if (!(dev->flags & IFF_UP))
 843                 return;
 844
 845         /* Add broadcast address, if it is explicitly assigned. */
 846         if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
 847                 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
 848
 849         if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
 850             (prefix != addr || ifa->ifa_prefixlen < 32)) {
 851                 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
 852                         fib_magic(RTM_NEWROUTE,
 853                                   dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
 854                                   prefix, ifa->ifa_prefixlen, prim);
 855
 856                 /* Add network specific broadcasts, when it takes a sense */
 857                 if (ifa->ifa_prefixlen < 31) {
 858                         fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
 859                         fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
 860                                   32, prim);
 861                 }
 862         }
 863 }
 864
 865 /* Delete primary or secondary address.
 866  * Optionally, on secondary address promotion consider the addresses
 867  * from subnet iprim as deleted, even if they are in device list.
 868  * In this case the secondary ifa can be in device list.
 869  */
 870 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 871 {
 872         struct in_device *in_dev = ifa->ifa_dev;
 873         struct net_device *dev = in_dev->dev;
 874         struct in_ifaddr *ifa1;
 875         struct in_ifaddr *prim = ifa, *prim1 = NULL;
 876         __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
 877         __be32 any = ifa->ifa_address & ifa->ifa_mask;
 878 #define LOCAL_OK        1
 879 #define BRD_OK          2
 880 #define BRD0_OK         4
 881 #define BRD1_OK         8
 882         unsigned int ok = 0;
 883         int subnet = 0;         /* Primary network */
 884         int gone = 1;           /* Address is missing */
 885         int same_prefsrc = 0;   /* Another primary with same IP */
 886
 887         if (ifa->ifa_flags & IFA_F_SECONDARY) {
 888                 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
 889                 if (!prim) {
 890                         /* if the device has been deleted, we don't perform
 891                          * address promotion
 892                          */
 893                         if (!in_dev->dead)
 894                                 pr_warn("%s: bug: prim == NULL\n", __func__);
 895                         return;
 896                 }
 897                 if (iprim && iprim != prim) {
 898                         pr_warn("%s: bug: iprim != prim\n", __func__);
 899                         return;
 900                 }
 901         } else if (!ipv4_is_zeronet(any) &&
 902                    (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
 903                 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
 904                         fib_magic(RTM_DELROUTE,
 905                                   dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
 906                                   any, ifa->ifa_prefixlen, prim);
 907                 subnet = 1;
 908         }
 909
 910         if (in_dev->dead)
 911                 goto no_promotions;
 912
 913         /* Deletion is more complicated than add.
 914          * We should take care of not to delete too much :-)
 915          *
 916          * Scan address list to be sure that addresses are really gone.
 917          */
 918
 919         for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
 920                 if (ifa1 == ifa) {
 921                         /* promotion, keep the IP */
 922                         gone = 0;
 923                         continue;
 924                 }
 925                 /* Ignore IFAs from our subnet */
 926                 if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
 927                     inet_ifa_match(ifa1->ifa_address, iprim))
 928                         continue;
 929
 930                 /* Ignore ifa1 if it uses different primary IP (prefsrc) */
 931                 if (ifa1->ifa_flags & IFA_F_SECONDARY) {
 932                         /* Another address from our subnet? */
 933                         if (ifa1->ifa_mask == prim->ifa_mask &&
 934                             inet_ifa_match(ifa1->ifa_address, prim))
 935                                 prim1 = prim;
 936                         else {
 937                                 /* We reached the secondaries, so
 938                                  * same_prefsrc should be determined.
 939                                  */
 940                                 if (!same_prefsrc)
 941                                         continue;
 942                                 /* Search new prim1 if ifa1 is not
 943                                  * using the current prim1
 944                                  */
 945                                 if (!prim1 ||
 946                                     ifa1->ifa_mask != prim1->ifa_mask ||
 947                                     !inet_ifa_match(ifa1->ifa_address, prim1))
 948                                         prim1 = inet_ifa_byprefix(in_dev,
 949                                                         ifa1->ifa_address,
 950                                                         ifa1->ifa_mask);
 951                                 if (!prim1)
 952                                         continue;
 953                                 if (prim1->ifa_local != prim->ifa_local)
 954                                         continue;
 955                         }
 956                 } else {
 957                         if (prim->ifa_local != ifa1->ifa_local)
 958                                 continue;
 959                         prim1 = ifa1;
 960                         if (prim != prim1)
 961                                 same_prefsrc = 1;
 962                 }
 963                 if (ifa->ifa_local == ifa1->ifa_local)
 964                         ok |= LOCAL_OK;
 965                 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
 966                         ok |= BRD_OK;
 967                 if (brd == ifa1->ifa_broadcast)
 968                         ok |= BRD1_OK;
 969                 if (any == ifa1->ifa_broadcast)
 970                         ok |= BRD0_OK;
 971                 /* primary has network specific broadcasts */
 972                 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
 973                         __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
 974                         __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
 975
 976                         if (!ipv4_is_zeronet(any1)) {
 977                                 if (ifa->ifa_broadcast == brd1 ||
 978                                     ifa->ifa_broadcast == any1)
 979                                         ok |= BRD_OK;
 980                                 if (brd == brd1 || brd == any1)
 981                                         ok |= BRD1_OK;
 982                                 if (any == brd1 || any == any1)
 983                                         ok |= BRD0_OK;
 984                         }
 985                 }
 986         }
 987
 988 no_promotions:
 989         if (!(ok & BRD_OK))
 990                 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
 991         if (subnet && ifa->ifa_prefixlen < 31) {
 992                 if (!(ok & BRD1_OK))
 993                         fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
 994                 if (!(ok & BRD0_OK))
 995                         fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
 996         }
 997         if (!(ok & LOCAL_OK)) {
 998                 unsigned int addr_type;
 999
1000                 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
1001
1002                 /* Check, that this local address finally disappeared. */
1003                 addr_type = inet_addr_type_dev_table(dev_net(dev), dev,
1004                                                      ifa->ifa_local);
1005                 if (gone && addr_type != RTN_LOCAL) {
1006                         /* And the last, but not the least thing.
1007                          * We must flush stray FIB entries.
1008                          *
1009                          * First of all, we scan fib_info list searching
1010                          * for stray nexthop entries, then ignite fib_flush.
1011                          */
1012                         if (fib_sync_down_addr(dev, ifa->ifa_local))
1013                                 fib_flush(dev_net(dev));
1014                 }
1015         }
1016 #undef LOCAL_OK
1017 #undef BRD_OK
1018 #undef BRD0_OK
1019 #undef BRD1_OK
1020 }
1021
1022 static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn)
1023 {
1024
1025         struct fib_result       res;
1026         struct flowi4           fl4 = {
1027                 .flowi4_mark = frn->fl_mark,
1028                 .daddr = frn->fl_addr,
1029                 .flowi4_tos = frn->fl_tos,
1030                 .flowi4_scope = frn->fl_scope,
1031         };
1032         struct fib_table *tb;
1033
1034         rcu_read_lock();
1035
1036         tb = fib_get_table(net, frn->tb_id_in);
1037
1038         frn->err = -ENOENT;
1039         if (tb) {
1040                 local_bh_disable();
1041
1042                 frn->tb_id = tb->tb_id;
1043                 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
1044
1045                 if (!frn->err) {
1046                         frn->prefixlen = res.prefixlen;
1047                         frn->nh_sel = res.nh_sel;
1048                         frn->type = res.type;
1049                         frn->scope = res.scope;
1050                 }
1051                 local_bh_enable();
1052         }
1053
1054         rcu_read_unlock();
1055 }
1056
1057 static void nl_fib_input(struct sk_buff *skb)
1058 {
1059         struct net *net;
1060         struct fib_result_nl *frn;
1061         struct nlmsghdr *nlh;
1062         u32 portid;
1063
1064         net = sock_net(skb->sk);
1065         nlh = nlmsg_hdr(skb);
1066         if (skb->len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len ||
1067             nlmsg_len(nlh) < sizeof(*frn))
1068                 return;
1069
1070         skb = netlink_skb_clone(skb, GFP_KERNEL);
1071         if (!skb)
1072                 return;
1073         nlh = nlmsg_hdr(skb);
1074
1075         frn = (struct fib_result_nl *) nlmsg_data(nlh);
1076         nl_fib_lookup(net, frn);
1077
1078         portid = NETLINK_CB(skb).portid;      /* netlink portid */
1079         NETLINK_CB(skb).portid = 0;        /* from kernel */
1080         NETLINK_CB(skb).dst_group = 0;  /* unicast */
1081         netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT);
1082 }
1083
1084 static int __net_init nl_fib_lookup_init(struct net *net)
1085 {
1086         struct sock *sk;
1087         struct netlink_kernel_cfg cfg = {
1088                 .input  = nl_fib_input,
1089         };
1090
1091         sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg);
1092         if (!sk)
1093                 return -EAFNOSUPPORT;
1094         net->ipv4.fibnl = sk;
1095         return 0;
1096 }
1097
1098 static void nl_fib_lookup_exit(struct net *net)
1099 {
1100         netlink_kernel_release(net->ipv4.fibnl);
1101         net->ipv4.fibnl = NULL;
1102 }
1103
1104 static void fib_disable_ip(struct net_device *dev, unsigned long event,
1105                            bool force)
1106 {
1107         if (fib_sync_down_dev(dev, event, force))
1108                 fib_flush(dev_net(dev));
1109         rt_cache_flush(dev_net(dev));
1110         arp_ifdown(dev);
1111 }
1112
1113 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
1114 {
1115         struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
1116         struct net_device *dev = ifa->ifa_dev->dev;
1117         struct net *net = dev_net(dev);
1118
1119         switch (event) {
1120         case NETDEV_UP:
1121                 fib_add_ifaddr(ifa);
1122 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1123                 fib_sync_up(dev, RTNH_F_DEAD);
1124 #endif
1125                 atomic_inc(&net->ipv4.dev_addr_genid);
1126                 rt_cache_flush(dev_net(dev));
1127                 break;
1128         case NETDEV_DOWN:
1129                 fib_del_ifaddr(ifa, NULL);
1130                 atomic_inc(&net->ipv4.dev_addr_genid);
1131                 if (!ifa->ifa_dev->ifa_list) {
1132                         /* Last address was deleted from this interface.
1133                          * Disable IP.
1134                          */
1135                         fib_disable_ip(dev, event, true);
1136                 } else {
1137                         rt_cache_flush(dev_net(dev));
1138                 }
1139                 break;
1140         }
1141         return NOTIFY_DONE;
1142 }
1143
1144 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1145 {
1146         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1147         struct netdev_notifier_changeupper_info *info;
1148         struct in_device *in_dev;
1149         struct net *net = dev_net(dev);
1150         unsigned int flags;
1151
1152         if (event == NETDEV_UNREGISTER) {
1153                 fib_disable_ip(dev, event, true);
1154                 rt_flush_dev(dev);
1155                 return NOTIFY_DONE;
1156         }
1157
1158         in_dev = __in_dev_get_rtnl(dev);
1159         if (!in_dev)
1160                 return NOTIFY_DONE;
1161
1162         switch (event) {
1163         case NETDEV_UP:
1164                 for_ifa(in_dev) {
1165                         fib_add_ifaddr(ifa);
1166                 } endfor_ifa(in_dev);
1167 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1168                 fib_sync_up(dev, RTNH_F_DEAD);
1169 #endif
1170                 atomic_inc(&net->ipv4.dev_addr_genid);
1171                 rt_cache_flush(net);
1172                 break;
1173         case NETDEV_DOWN:
1174                 fib_disable_ip(dev, event, false);
1175                 break;
1176         case NETDEV_CHANGE:
1177                 flags = dev_get_flags(dev);
1178                 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1179                         fib_sync_up(dev, RTNH_F_LINKDOWN);
1180                 else
1181                         fib_sync_down_dev(dev, event, false);
1182                 /* fall through */
1183         case NETDEV_CHANGEMTU:
1184                 rt_cache_flush(net);
1185                 break;
1186         case NETDEV_CHANGEUPPER:
1187                 info = ptr;
1188                 /* flush all routes if dev is linked to or unlinked from
1189                  * an L3 master device (e.g., VRF)
1190                  */
1191                 if (info->upper_dev && netif_is_l3_master(info->upper_dev))
1192                         fib_disable_ip(dev, NETDEV_DOWN, true);
1193                 break;
1194         }
1195         return NOTIFY_DONE;
1196 }
1197
1198 static struct notifier_block fib_inetaddr_notifier = {
1199         .notifier_call = fib_inetaddr_event,
1200 };
1201
1202 static struct notifier_block fib_netdev_notifier = {
1203         .notifier_call = fib_netdev_event,
1204 };
1205
1206 static int __net_init ip_fib_net_init(struct net *net)
1207 {
1208         int err;
1209         size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
1210
1211         /* Avoid false sharing : Use at least a full cache line */
1212         size = max_t(size_t, size, L1_CACHE_BYTES);
1213
1214         net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
1215         if (!net->ipv4.fib_table_hash)
1216                 return -ENOMEM;
1217
1218         err = fib4_rules_init(net);
1219         if (err < 0)
1220                 goto fail;
1221         return 0;
1222
1223 fail:
1224         kfree(net->ipv4.fib_table_hash);
1225         return err;
1226 }
1227
1228 static void ip_fib_net_exit(struct net *net)
1229 {
1230         unsigned int i;
1231
1232         rtnl_lock();
1233 #ifdef CONFIG_IP_MULTIPLE_TABLES
1234         RCU_INIT_POINTER(net->ipv4.fib_main, NULL);
1235         RCU_INIT_POINTER(net->ipv4.fib_default, NULL);
1236 #endif
1237         for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1238                 struct hlist_head *head = &net->ipv4.fib_table_hash[i];
1239                 struct hlist_node *tmp;
1240                 struct fib_table *tb;
1241
1242                 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) {
1243                         hlist_del(&tb->tb_hlist);
1244                         fib_table_flush(net, tb);
1245                         fib_free_table(tb);
1246                 }
1247         }
1248
1249 #ifdef CONFIG_IP_MULTIPLE_TABLES
1250         fib4_rules_exit(net);
1251 #endif
1252         rtnl_unlock();
1253         kfree(net->ipv4.fib_table_hash);
1254 }
1255
1256 static int __net_init fib_net_init(struct net *net)
1257 {
1258         int error;
1259
1260 #ifdef CONFIG_IP_ROUTE_CLASSID
1261         net->ipv4.fib_num_tclassid_users = 0;
1262 #endif
1263         error = ip_fib_net_init(net);
1264         if (error < 0)
1265                 goto out;
1266         error = nl_fib_lookup_init(net);
1267         if (error < 0)
1268                 goto out_nlfl;
1269         error = fib_proc_init(net);
1270         if (error < 0)
1271                 goto out_proc;
1272 out:
1273         return error;
1274
1275 out_proc:
1276         nl_fib_lookup_exit(net);
1277 out_nlfl:
1278         ip_fib_net_exit(net);
1279         goto out;
1280 }
1281
1282 static void __net_exit fib_net_exit(struct net *net)
1283 {
1284         fib_proc_exit(net);
1285         nl_fib_lookup_exit(net);
1286         ip_fib_net_exit(net);
1287 }
1288
1289 static struct pernet_operations fib_net_ops = {
1290         .init = fib_net_init,
1291         .exit = fib_net_exit,
1292 };
1293
1294 void __init ip_fib_init(void)
1295 {
1296         rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
1297         rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
1298         rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
1299
1300         register_pernet_subsys(&fib_net_ops);
1301         register_netdevice_notifier(&fib_netdev_notifier);
1302         register_inetaddr_notifier(&fib_inetaddr_notifier);
1303
1304         fib_trie_init();
1305 }