net/core/fib_rules.c

   1 /*
   2  * net/core/fib_rules.c         Generic Routing Rules
   3  *
   4  *      This program is free software; you can redistribute it and/or
   5  *      modify it under the terms of the GNU General Public License as
   6  *      published by the Free Software Foundation, version 2.
   7  *
   8  * Authors:     Thomas Graf <tgraf@suug.ch>
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/kernel.h>
  13 #include <linux/list.h>
  14 #include <net/net_namespace.h>
  15 #include <net/sock.h>
  16 #include <net/fib_rules.h>
  17
  18 int fib_default_rule_add(struct fib_rules_ops *ops,
  19                          u32 pref, u32 table, u32 flags)
  20 {
  21         struct fib_rule *r;
  22
  23         r = kzalloc(ops->rule_size, GFP_KERNEL);
  24         if (r == NULL)
  25                 return -ENOMEM;
  26
  27         atomic_set(&r->refcnt, 1);
  28         r->action = FR_ACT_TO_TBL;
  29         r->pref = pref;
  30         r->table = table;
  31         r->flags = flags;
  32         r->fr_net = hold_net(ops->fro_net);
  33
  34         /* The lock is not required here, the list in unreacheable
  35          * at the moment this function is called */
  36         list_add_tail(&r->list, &ops->rules_list);
  37         return 0;
  38 }
  39 EXPORT_SYMBOL(fib_default_rule_add);
  40
  41 static void notify_rule_change(int event, struct fib_rule *rule,
  42                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
  43                                u32 pid);
  44
  45 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
  46 {
  47         struct fib_rules_ops *ops;
  48
  49         rcu_read_lock();
  50         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
  51                 if (ops->family == family) {
  52                         if (!try_module_get(ops->owner))
  53                                 ops = NULL;
  54                         rcu_read_unlock();
  55                         return ops;
  56                 }
  57         }
  58         rcu_read_unlock();
  59
  60         return NULL;
  61 }
  62
  63 static void rules_ops_put(struct fib_rules_ops *ops)
  64 {
  65         if (ops)
  66                 module_put(ops->owner);
  67 }
  68
  69 static void flush_route_cache(struct fib_rules_ops *ops)
  70 {
  71         if (ops->flush_cache)
  72                 ops->flush_cache(ops);
  73 }
  74
  75 static int __fib_rules_register(struct fib_rules_ops *ops)
  76 {
  77         int err = -EEXIST;
  78         struct fib_rules_ops *o;
  79         struct net *net;
  80
  81         net = ops->fro_net;
  82
  83         if (ops->rule_size < sizeof(struct fib_rule))
  84                 return -EINVAL;
  85
  86         if (ops->match == NULL || ops->configure == NULL ||
  87             ops->compare == NULL || ops->fill == NULL ||
  88             ops->action == NULL)
  89                 return -EINVAL;
  90
  91         spin_lock(&net->rules_mod_lock);
  92         list_for_each_entry(o, &net->rules_ops, list)
  93                 if (ops->family == o->family)
  94                         goto errout;
  95
  96         hold_net(net);
  97         list_add_tail_rcu(&ops->list, &net->rules_ops);
  98         err = 0;
  99 errout:
 100         spin_unlock(&net->rules_mod_lock);
 101
 102         return err;
 103 }
 104
 105 struct fib_rules_ops *
 106 fib_rules_register(struct fib_rules_ops *tmpl, struct net *net)
 107 {
 108         struct fib_rules_ops *ops;
 109         int err;
 110
 111         ops = kmemdup(tmpl, sizeof (*ops), GFP_KERNEL);
 112         if (ops == NULL)
 113                 return ERR_PTR(-ENOMEM);
 114
 115         INIT_LIST_HEAD(&ops->rules_list);
 116         ops->fro_net = net;
 117
 118         err = __fib_rules_register(ops);
 119         if (err) {
 120                 kfree(ops);
 121                 ops = ERR_PTR(err);
 122         }
 123
 124         return ops;
 125 }
 126
 127 EXPORT_SYMBOL_GPL(fib_rules_register);
 128
 129 void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
 130 {
 131         struct fib_rule *rule, *tmp;
 132
 133         list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
 134                 list_del_rcu(&rule->list);
 135                 fib_rule_put(rule);
 136         }
 137 }
 138 EXPORT_SYMBOL_GPL(fib_rules_cleanup_ops);
 139
 140 static void fib_rules_put_rcu(struct rcu_head *head)
 141 {
 142         struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu);
 143         struct net *net = ops->fro_net;
 144
 145         release_net(net);
 146         kfree(ops);
 147 }
 148
 149 void fib_rules_unregister(struct fib_rules_ops *ops)
 150 {
 151         struct net *net = ops->fro_net;
 152
 153         spin_lock(&net->rules_mod_lock);
 154         list_del_rcu(&ops->list);
 155         fib_rules_cleanup_ops(ops);
 156         spin_unlock(&net->rules_mod_lock);
 157
 158         call_rcu(&ops->rcu, fib_rules_put_rcu);
 159 }
 160
 161 EXPORT_SYMBOL_GPL(fib_rules_unregister);
 162
 163 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
 164                           struct flowi *fl, int flags)
 165 {
 166         int ret = 0;
 167
 168         if (rule->iifindex && (rule->iifindex != fl->iif))
 169                 goto out;
 170
 171         if (rule->oifindex && (rule->oifindex != fl->oif))
 172                 goto out;
 173
 174         if ((rule->mark ^ fl->mark) & rule->mark_mask)
 175                 goto out;
 176
 177         ret = ops->match(rule, fl, flags);
 178 out:
 179         return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
 180 }
 181
 182 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
 183                      int flags, struct fib_lookup_arg *arg)
 184 {
 185         struct fib_rule *rule;
 186         int err;
 187
 188         rcu_read_lock();
 189
 190         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 191 jumped:
 192                 if (!fib_rule_match(rule, ops, fl, flags))
 193                         continue;
 194
 195                 if (rule->action == FR_ACT_GOTO) {
 196                         struct fib_rule *target;
 197
 198                         target = rcu_dereference(rule->ctarget);
 199                         if (target == NULL) {
 200                                 continue;
 201                         } else {
 202                                 rule = target;
 203                                 goto jumped;
 204                         }
 205                 } else if (rule->action == FR_ACT_NOP)
 206                         continue;
 207                 else
 208                         err = ops->action(rule, fl, flags, arg);
 209
 210                 if (err != -EAGAIN) {
 211                         fib_rule_get(rule);
 212                         arg->rule = rule;
 213                         goto out;
 214                 }
 215         }
 216
 217         err = -ESRCH;
 218 out:
 219         rcu_read_unlock();
 220
 221         return err;
 222 }
 223
 224 EXPORT_SYMBOL_GPL(fib_rules_lookup);
 225
 226 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
 227                             struct fib_rules_ops *ops)
 228 {
 229         int err = -EINVAL;
 230
 231         if (frh->src_len)
 232                 if (tb[FRA_SRC] == NULL ||
 233                     frh->src_len > (ops->addr_size * 8) ||
 234                     nla_len(tb[FRA_SRC]) != ops->addr_size)
 235                         goto errout;
 236
 237         if (frh->dst_len)
 238                 if (tb[FRA_DST] == NULL ||
 239                     frh->dst_len > (ops->addr_size * 8) ||
 240                     nla_len(tb[FRA_DST]) != ops->addr_size)
 241                         goto errout;
 242
 243         err = 0;
 244 errout:
 245         return err;
 246 }
 247
 248 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 249 {
 250         struct net *net = sock_net(skb->sk);
 251         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 252         struct fib_rules_ops *ops = NULL;
 253         struct fib_rule *rule, *r, *last = NULL;
 254         struct nlattr *tb[FRA_MAX+1];
 255         int err = -EINVAL, unresolved = 0;
 256
 257         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 258                 goto errout;
 259
 260         ops = lookup_rules_ops(net, frh->family);
 261         if (ops == NULL) {
 262                 err = -EAFNOSUPPORT;
 263                 goto errout;
 264         }
 265
 266         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 267         if (err < 0)
 268                 goto errout;
 269
 270         err = validate_rulemsg(frh, tb, ops);
 271         if (err < 0)
 272                 goto errout;
 273
 274         rule = kzalloc(ops->rule_size, GFP_KERNEL);
 275         if (rule == NULL) {
 276                 err = -ENOMEM;
 277                 goto errout;
 278         }
 279         rule->fr_net = hold_net(net);
 280
 281         if (tb[FRA_PRIORITY])
 282                 rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
 283
 284         if (tb[FRA_IIFNAME]) {
 285                 struct net_device *dev;
 286
 287                 rule->iifindex = -1;
 288                 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
 289                 dev = __dev_get_by_name(net, rule->iifname);
 290                 if (dev)
 291                         rule->iifindex = dev->ifindex;
 292         }
 293
 294         if (tb[FRA_OIFNAME]) {
 295                 struct net_device *dev;
 296
 297                 rule->oifindex = -1;
 298                 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
 299                 dev = __dev_get_by_name(net, rule->oifname);
 300                 if (dev)
 301                         rule->oifindex = dev->ifindex;
 302         }
 303
 304         if (tb[FRA_FWMARK]) {
 305                 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
 306                 if (rule->mark)
 307                         /* compatibility: if the mark value is non-zero all bits
 308                          * are compared unless a mask is explicitly specified.
 309                          */
 310                         rule->mark_mask = 0xFFFFFFFF;
 311         }
 312
 313         if (tb[FRA_FWMASK])
 314                 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
 315
 316         rule->action = frh->action;
 317         rule->flags = frh->flags;
 318         rule->table = frh_get_table(frh, tb);
 319
 320         if (!tb[FRA_PRIORITY] && ops->default_pref)
 321                 rule->pref = ops->default_pref(ops);
 322
 323         err = -EINVAL;
 324         if (tb[FRA_GOTO]) {
 325                 if (rule->action != FR_ACT_GOTO)
 326                         goto errout_free;
 327
 328                 rule->target = nla_get_u32(tb[FRA_GOTO]);
 329                 /* Backward jumps are prohibited to avoid endless loops */
 330                 if (rule->target <= rule->pref)
 331                         goto errout_free;
 332
 333                 list_for_each_entry(r, &ops->rules_list, list) {
 334                         if (r->pref == rule->target) {
 335                                 rule->ctarget = r;
 336                                 break;
 337                         }
 338                 }
 339
 340                 if (rule->ctarget == NULL)
 341                         unresolved = 1;
 342         } else if (rule->action == FR_ACT_GOTO)
 343                 goto errout_free;
 344
 345         err = ops->configure(rule, skb, frh, tb);
 346         if (err < 0)
 347                 goto errout_free;
 348
 349         list_for_each_entry(r, &ops->rules_list, list) {
 350                 if (r->pref > rule->pref)
 351                         break;
 352                 last = r;
 353         }
 354
 355         fib_rule_get(rule);
 356
 357         if (ops->unresolved_rules) {
 358                 /*
 359                  * There are unresolved goto rules in the list, check if
 360                  * any of them are pointing to this new rule.
 361                  */
 362                 list_for_each_entry(r, &ops->rules_list, list) {
 363                         if (r->action == FR_ACT_GOTO &&
 364                             r->target == rule->pref) {
 365                                 BUG_ON(r->ctarget != NULL);
 366                                 rcu_assign_pointer(r->ctarget, rule);
 367                                 if (--ops->unresolved_rules == 0)
 368                                         break;
 369                         }
 370                 }
 371         }
 372
 373         if (rule->action == FR_ACT_GOTO)
 374                 ops->nr_goto_rules++;
 375
 376         if (unresolved)
 377                 ops->unresolved_rules++;
 378
 379         if (last)
 380                 list_add_rcu(&rule->list, &last->list);
 381         else
 382                 list_add_rcu(&rule->list, &ops->rules_list);
 383
 384         notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
 385         flush_route_cache(ops);
 386         rules_ops_put(ops);
 387         return 0;
 388
 389 errout_free:
 390         release_net(rule->fr_net);
 391         kfree(rule);
 392 errout:
 393         rules_ops_put(ops);
 394         return err;
 395 }
 396
 397 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 398 {
 399         struct net *net = sock_net(skb->sk);
 400         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 401         struct fib_rules_ops *ops = NULL;
 402         struct fib_rule *rule, *tmp;
 403         struct nlattr *tb[FRA_MAX+1];
 404         int err = -EINVAL;
 405
 406         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 407                 goto errout;
 408
 409         ops = lookup_rules_ops(net, frh->family);
 410         if (ops == NULL) {
 411                 err = -EAFNOSUPPORT;
 412                 goto errout;
 413         }
 414
 415         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 416         if (err < 0)
 417                 goto errout;
 418
 419         err = validate_rulemsg(frh, tb, ops);
 420         if (err < 0)
 421                 goto errout;
 422
 423         list_for_each_entry(rule, &ops->rules_list, list) {
 424                 if (frh->action && (frh->action != rule->action))
 425                         continue;
 426
 427                 if (frh->table && (frh_get_table(frh, tb) != rule->table))
 428                         continue;
 429
 430                 if (tb[FRA_PRIORITY] &&
 431                     (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
 432                         continue;
 433
 434                 if (tb[FRA_IIFNAME] &&
 435                     nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
 436                         continue;
 437
 438                 if (tb[FRA_OIFNAME] &&
 439                     nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
 440                         continue;
 441
 442                 if (tb[FRA_FWMARK] &&
 443                     (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
 444                         continue;
 445
 446                 if (tb[FRA_FWMASK] &&
 447                     (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
 448                         continue;
 449
 450                 if (!ops->compare(rule, frh, tb))
 451                         continue;
 452
 453                 if (rule->flags & FIB_RULE_PERMANENT) {
 454                         err = -EPERM;
 455                         goto errout;
 456                 }
 457
 458                 list_del_rcu(&rule->list);
 459
 460                 if (rule->action == FR_ACT_GOTO)
 461                         ops->nr_goto_rules--;
 462
 463                 /*
 464                  * Check if this rule is a target to any of them. If so,
 465                  * disable them. As this operation is eventually very
 466                  * expensive, it is only performed if goto rules have
 467                  * actually been added.
 468                  */
 469                 if (ops->nr_goto_rules > 0) {
 470                         list_for_each_entry(tmp, &ops->rules_list, list) {
 471                                 if (tmp->ctarget == rule) {
 472                                         rcu_assign_pointer(tmp->ctarget, NULL);
 473                                         ops->unresolved_rules++;
 474                                 }
 475                         }
 476                 }
 477
 478                 synchronize_rcu();
 479                 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
 480                                    NETLINK_CB(skb).pid);
 481                 fib_rule_put(rule);
 482                 flush_route_cache(ops);
 483                 rules_ops_put(ops);
 484                 return 0;
 485         }
 486
 487         err = -ENOENT;
 488 errout:
 489         rules_ops_put(ops);
 490         return err;
 491 }
 492
 493 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
 494                                          struct fib_rule *rule)
 495 {
 496         size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
 497                          + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
 498                          + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
 499                          + nla_total_size(4) /* FRA_PRIORITY */
 500                          + nla_total_size(4) /* FRA_TABLE */
 501                          + nla_total_size(4) /* FRA_FWMARK */
 502                          + nla_total_size(4); /* FRA_FWMASK */
 503
 504         if (ops->nlmsg_payload)
 505                 payload += ops->nlmsg_payload(rule);
 506
 507         return payload;
 508 }
 509
 510 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
 511                             u32 pid, u32 seq, int type, int flags,
 512                             struct fib_rules_ops *ops)
 513 {
 514         struct nlmsghdr *nlh;
 515         struct fib_rule_hdr *frh;
 516
 517         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
 518         if (nlh == NULL)
 519                 return -EMSGSIZE;
 520
 521         frh = nlmsg_data(nlh);
 522         frh->table = rule->table;
 523         NLA_PUT_U32(skb, FRA_TABLE, rule->table);
 524         frh->res1 = 0;
 525         frh->res2 = 0;
 526         frh->action = rule->action;
 527         frh->flags = rule->flags;
 528
 529         if (rule->action == FR_ACT_GOTO && rule->ctarget == NULL)
 530                 frh->flags |= FIB_RULE_UNRESOLVED;
 531
 532         if (rule->iifname[0]) {
 533                 NLA_PUT_STRING(skb, FRA_IIFNAME, rule->iifname);
 534
 535                 if (rule->iifindex == -1)
 536                         frh->flags |= FIB_RULE_IIF_DETACHED;
 537         }
 538
 539         if (rule->oifname[0]) {
 540                 NLA_PUT_STRING(skb, FRA_OIFNAME, rule->oifname);
 541
 542                 if (rule->oifindex == -1)
 543                         frh->flags |= FIB_RULE_OIF_DETACHED;
 544         }
 545
 546         if (rule->pref)
 547                 NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
 548
 549         if (rule->mark)
 550                 NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
 551
 552         if (rule->mark_mask || rule->mark)
 553                 NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
 554
 555         if (rule->target)
 556                 NLA_PUT_U32(skb, FRA_GOTO, rule->target);
 557
 558         if (ops->fill(rule, skb, frh) < 0)
 559                 goto nla_put_failure;
 560
 561         return nlmsg_end(skb, nlh);
 562
 563 nla_put_failure:
 564         nlmsg_cancel(skb, nlh);
 565         return -EMSGSIZE;
 566 }
 567
 568 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
 569                       struct fib_rules_ops *ops)
 570 {
 571         int idx = 0;
 572         struct fib_rule *rule;
 573
 574         list_for_each_entry(rule, &ops->rules_list, list) {
 575                 if (idx < cb->args[1])
 576                         goto skip;
 577
 578                 if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
 579                                      cb->nlh->nlmsg_seq, RTM_NEWRULE,
 580                                      NLM_F_MULTI, ops) < 0)
 581                         break;
 582 skip:
 583                 idx++;
 584         }
 585         cb->args[1] = idx;
 586         rules_ops_put(ops);
 587
 588         return skb->len;
 589 }
 590
 591 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 592 {
 593         struct net *net = sock_net(skb->sk);
 594         struct fib_rules_ops *ops;
 595         int idx = 0, family;
 596
 597         family = rtnl_msg_family(cb->nlh);
 598         if (family != AF_UNSPEC) {
 599                 /* Protocol specific dump request */
 600                 ops = lookup_rules_ops(net, family);
 601                 if (ops == NULL)
 602                         return -EAFNOSUPPORT;
 603
 604                 return dump_rules(skb, cb, ops);
 605         }
 606
 607         rcu_read_lock();
 608         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 609                 if (idx < cb->args[0] || !try_module_get(ops->owner))
 610                         goto skip;
 611
 612                 if (dump_rules(skb, cb, ops) < 0)
 613                         break;
 614
 615                 cb->args[1] = 0;
 616         skip:
 617                 idx++;
 618         }
 619         rcu_read_unlock();
 620         cb->args[0] = idx;
 621
 622         return skb->len;
 623 }
 624
 625 static void notify_rule_change(int event, struct fib_rule *rule,
 626                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
 627                                u32 pid)
 628 {
 629         struct net *net;
 630         struct sk_buff *skb;
 631         int err = -ENOBUFS;
 632
 633         net = ops->fro_net;
 634         skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
 635         if (skb == NULL)
 636                 goto errout;
 637
 638         err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
 639         if (err < 0) {
 640                 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
 641                 WARN_ON(err == -EMSGSIZE);
 642                 kfree_skb(skb);
 643                 goto errout;
 644         }
 645
 646         rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
 647         return;
 648 errout:
 649         if (err < 0)
 650                 rtnl_set_sk_err(net, ops->nlgroup, err);
 651 }
 652
 653 static void attach_rules(struct list_head *rules, struct net_device *dev)
 654 {
 655         struct fib_rule *rule;
 656
 657         list_for_each_entry(rule, rules, list) {
 658                 if (rule->iifindex == -1 &&
 659                     strcmp(dev->name, rule->iifname) == 0)
 660                         rule->iifindex = dev->ifindex;
 661                 if (rule->oifindex == -1 &&
 662                     strcmp(dev->name, rule->oifname) == 0)
 663                         rule->oifindex = dev->ifindex;
 664         }
 665 }
 666
 667 static void detach_rules(struct list_head *rules, struct net_device *dev)
 668 {
 669         struct fib_rule *rule;
 670
 671         list_for_each_entry(rule, rules, list) {
 672                 if (rule->iifindex == dev->ifindex)
 673                         rule->iifindex = -1;
 674                 if (rule->oifindex == dev->ifindex)
 675                         rule->oifindex = -1;
 676         }
 677 }
 678
 679
 680 static int fib_rules_event(struct notifier_block *this, unsigned long event,
 681                             void *ptr)
 682 {
 683         struct net_device *dev = ptr;
 684         struct net *net = dev_net(dev);
 685         struct fib_rules_ops *ops;
 686
 687         ASSERT_RTNL();
 688         rcu_read_lock();
 689
 690         switch (event) {
 691         case NETDEV_REGISTER:
 692                 list_for_each_entry(ops, &net->rules_ops, list)
 693                         attach_rules(&ops->rules_list, dev);
 694                 break;
 695
 696         case NETDEV_UNREGISTER:
 697                 list_for_each_entry(ops, &net->rules_ops, list)
 698                         detach_rules(&ops->rules_list, dev);
 699                 break;
 700         }
 701
 702         rcu_read_unlock();
 703
 704         return NOTIFY_DONE;
 705 }
 706
 707 static struct notifier_block fib_rules_notifier = {
 708         .notifier_call = fib_rules_event,
 709 };
 710
 711 static int __net_init fib_rules_net_init(struct net *net)
 712 {
 713         INIT_LIST_HEAD(&net->rules_ops);
 714         spin_lock_init(&net->rules_mod_lock);
 715         return 0;
 716 }
 717
 718 static struct pernet_operations fib_rules_net_ops = {
 719         .init = fib_rules_net_init,
 720 };
 721
 722 static int __init fib_rules_init(void)
 723 {
 724         int err;
 725         rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL);
 726         rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL);
 727         rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule);
 728
 729         err = register_pernet_subsys(&fib_rules_net_ops);
 730         if (err < 0)
 731                 goto fail;
 732
 733         err = register_netdevice_notifier(&fib_rules_notifier);
 734         if (err < 0)
 735                 goto fail_unregister;
 736
 737         return 0;
 738
 739 fail_unregister:
 740         unregister_pernet_subsys(&fib_rules_net_ops);
 741 fail:
 742         rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
 743         rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
 744         rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
 745         return err;
 746 }
 747
 748 subsys_initcall(fib_rules_init);