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