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/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 u32 fib_default_rule_pref(struct fib_rules_ops *ops)
  43 {
  44         struct list_head *pos;
  45         struct fib_rule *rule;
  46
  47         if (!list_empty(&ops->rules_list)) {
  48                 pos = ops->rules_list.next;
  49                 if (pos->next != &ops->rules_list) {
  50                         rule = list_entry(pos->next, struct fib_rule, list);
  51                         if (rule->pref)
  52                                 return rule->pref - 1;
  53                 }
  54         }
  55
  56         return 0;
  57 }
  58 EXPORT_SYMBOL(fib_default_rule_pref);
  59
  60 static void notify_rule_change(int event, struct fib_rule *rule,
  61                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
  62                                u32 pid);
  63
  64 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
  65 {
  66         struct fib_rules_ops *ops;
  67
  68         rcu_read_lock();
  69         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
  70                 if (ops->family == family) {
  71                         if (!try_module_get(ops->owner))
  72                                 ops = NULL;
  73                         rcu_read_unlock();
  74                         return ops;
  75                 }
  76         }
  77         rcu_read_unlock();
  78
  79         return NULL;
  80 }
  81
  82 static void rules_ops_put(struct fib_rules_ops *ops)
  83 {
  84         if (ops)
  85                 module_put(ops->owner);
  86 }
  87
  88 static void flush_route_cache(struct fib_rules_ops *ops)
  89 {
  90         if (ops->flush_cache)
  91                 ops->flush_cache(ops);
  92 }
  93
  94 static int __fib_rules_register(struct fib_rules_ops *ops)
  95 {
  96         int err = -EEXIST;
  97         struct fib_rules_ops *o;
  98         struct net *net;
  99
 100         net = ops->fro_net;
 101
 102         if (ops->rule_size < sizeof(struct fib_rule))
 103                 return -EINVAL;
 104
 105         if (ops->match == NULL || ops->configure == NULL ||
 106             ops->compare == NULL || ops->fill == NULL ||
 107             ops->action == NULL)
 108                 return -EINVAL;
 109
 110         spin_lock(&net->rules_mod_lock);
 111         list_for_each_entry(o, &net->rules_ops, list)
 112                 if (ops->family == o->family)
 113                         goto errout;
 114
 115         hold_net(net);
 116         list_add_tail_rcu(&ops->list, &net->rules_ops);
 117         err = 0;
 118 errout:
 119         spin_unlock(&net->rules_mod_lock);
 120
 121         return err;
 122 }
 123
 124 struct fib_rules_ops *
 125 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
 126 {
 127         struct fib_rules_ops *ops;
 128         int err;
 129
 130         ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
 131         if (ops == NULL)
 132                 return ERR_PTR(-ENOMEM);
 133
 134         INIT_LIST_HEAD(&ops->rules_list);
 135         ops->fro_net = net;
 136
 137         err = __fib_rules_register(ops);
 138         if (err) {
 139                 kfree(ops);
 140                 ops = ERR_PTR(err);
 141         }
 142
 143         return ops;
 144 }
 145 EXPORT_SYMBOL_GPL(fib_rules_register);
 146
 147 void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
 148 {
 149         struct fib_rule *rule, *tmp;
 150
 151         list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
 152                 list_del_rcu(&rule->list);
 153                 fib_rule_put(rule);
 154         }
 155 }
 156 EXPORT_SYMBOL_GPL(fib_rules_cleanup_ops);
 157
 158 static void fib_rules_put_rcu(struct rcu_head *head)
 159 {
 160         struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu);
 161         struct net *net = ops->fro_net;
 162
 163         release_net(net);
 164         kfree(ops);
 165 }
 166
 167 void fib_rules_unregister(struct fib_rules_ops *ops)
 168 {
 169         struct net *net = ops->fro_net;
 170
 171         spin_lock(&net->rules_mod_lock);
 172         list_del_rcu(&ops->list);
 173         fib_rules_cleanup_ops(ops);
 174         spin_unlock(&net->rules_mod_lock);
 175
 176         call_rcu(&ops->rcu, fib_rules_put_rcu);
 177 }
 178 EXPORT_SYMBOL_GPL(fib_rules_unregister);
 179
 180 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
 181                           struct flowi *fl, int flags)
 182 {
 183         int ret = 0;
 184
 185         if (rule->iifindex && (rule->iifindex != fl->iif))
 186                 goto out;
 187
 188         if (rule->oifindex && (rule->oifindex != fl->oif))
 189                 goto out;
 190
 191         if ((rule->mark ^ fl->mark) & rule->mark_mask)
 192                 goto out;
 193
 194         ret = ops->match(rule, fl, flags);
 195 out:
 196         return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
 197 }
 198
 199 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
 200                      int flags, struct fib_lookup_arg *arg)
 201 {
 202         struct fib_rule *rule;
 203         int err;
 204
 205         rcu_read_lock();
 206
 207         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 208 jumped:
 209                 if (!fib_rule_match(rule, ops, fl, flags))
 210                         continue;
 211
 212                 if (rule->action == FR_ACT_GOTO) {
 213                         struct fib_rule *target;
 214
 215                         target = rcu_dereference(rule->ctarget);
 216                         if (target == NULL) {
 217                                 continue;
 218                         } else {
 219                                 rule = target;
 220                                 goto jumped;
 221                         }
 222                 } else if (rule->action == FR_ACT_NOP)
 223                         continue;
 224                 else
 225                         err = ops->action(rule, fl, flags, arg);
 226
 227                 if (err != -EAGAIN) {
 228                         fib_rule_get(rule);
 229                         arg->rule = rule;
 230                         goto out;
 231                 }
 232         }
 233
 234         err = -ESRCH;
 235 out:
 236         rcu_read_unlock();
 237
 238         return err;
 239 }
 240 EXPORT_SYMBOL_GPL(fib_rules_lookup);
 241
 242 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
 243                             struct fib_rules_ops *ops)
 244 {
 245         int err = -EINVAL;
 246
 247         if (frh->src_len)
 248                 if (tb[FRA_SRC] == NULL ||
 249                     frh->src_len > (ops->addr_size * 8) ||
 250                     nla_len(tb[FRA_SRC]) != ops->addr_size)
 251                         goto errout;
 252
 253         if (frh->dst_len)
 254                 if (tb[FRA_DST] == NULL ||
 255                     frh->dst_len > (ops->addr_size * 8) ||
 256                     nla_len(tb[FRA_DST]) != ops->addr_size)
 257                         goto errout;
 258
 259         err = 0;
 260 errout:
 261         return err;
 262 }
 263
 264 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 265 {
 266         struct net *net = sock_net(skb->sk);
 267         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 268         struct fib_rules_ops *ops = NULL;
 269         struct fib_rule *rule, *r, *last = NULL;
 270         struct nlattr *tb[FRA_MAX+1];
 271         int err = -EINVAL, unresolved = 0;
 272
 273         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 274                 goto errout;
 275
 276         ops = lookup_rules_ops(net, frh->family);
 277         if (ops == NULL) {
 278                 err = -EAFNOSUPPORT;
 279                 goto errout;
 280         }
 281
 282         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 283         if (err < 0)
 284                 goto errout;
 285
 286         err = validate_rulemsg(frh, tb, ops);
 287         if (err < 0)
 288                 goto errout;
 289
 290         rule = kzalloc(ops->rule_size, GFP_KERNEL);
 291         if (rule == NULL) {
 292                 err = -ENOMEM;
 293                 goto errout;
 294         }
 295         rule->fr_net = hold_net(net);
 296
 297         if (tb[FRA_PRIORITY])
 298                 rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
 299
 300         if (tb[FRA_IIFNAME]) {
 301                 struct net_device *dev;
 302
 303                 rule->iifindex = -1;
 304                 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
 305                 dev = __dev_get_by_name(net, rule->iifname);
 306                 if (dev)
 307                         rule->iifindex = dev->ifindex;
 308         }
 309
 310         if (tb[FRA_OIFNAME]) {
 311                 struct net_device *dev;
 312
 313                 rule->oifindex = -1;
 314                 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
 315                 dev = __dev_get_by_name(net, rule->oifname);
 316                 if (dev)
 317                         rule->oifindex = dev->ifindex;
 318         }
 319
 320         if (tb[FRA_FWMARK]) {
 321                 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
 322                 if (rule->mark)
 323                         /* compatibility: if the mark value is non-zero all bits
 324                          * are compared unless a mask is explicitly specified.
 325                          */
 326                         rule->mark_mask = 0xFFFFFFFF;
 327         }
 328
 329         if (tb[FRA_FWMASK])
 330                 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
 331
 332         rule->action = frh->action;
 333         rule->flags = frh->flags;
 334         rule->table = frh_get_table(frh, tb);
 335
 336         if (!tb[FRA_PRIORITY] && ops->default_pref)
 337                 rule->pref = ops->default_pref(ops);
 338
 339         err = -EINVAL;
 340         if (tb[FRA_GOTO]) {
 341                 if (rule->action != FR_ACT_GOTO)
 342                         goto errout_free;
 343
 344                 rule->target = nla_get_u32(tb[FRA_GOTO]);
 345                 /* Backward jumps are prohibited to avoid endless loops */
 346                 if (rule->target <= rule->pref)
 347                         goto errout_free;
 348
 349                 list_for_each_entry(r, &ops->rules_list, list) {
 350                         if (r->pref == rule->target) {
 351                                 rule->ctarget = r;
 352                                 break;
 353                         }
 354                 }
 355
 356                 if (rule->ctarget == NULL)
 357                         unresolved = 1;
 358         } else if (rule->action == FR_ACT_GOTO)
 359                 goto errout_free;
 360
 361         err = ops->configure(rule, skb, frh, tb);
 362         if (err < 0)
 363                 goto errout_free;
 364
 365         list_for_each_entry(r, &ops->rules_list, list) {
 366                 if (r->pref > rule->pref)
 367                         break;
 368                 last = r;
 369         }
 370
 371         fib_rule_get(rule);
 372
 373         if (ops->unresolved_rules) {
 374                 /*
 375                  * There are unresolved goto rules in the list, check if
 376                  * any of them are pointing to this new rule.
 377                  */
 378                 list_for_each_entry(r, &ops->rules_list, list) {
 379                         if (r->action == FR_ACT_GOTO &&
 380                             r->target == rule->pref) {
 381                                 BUG_ON(r->ctarget != NULL);
 382                                 rcu_assign_pointer(r->ctarget, rule);
 383                                 if (--ops->unresolved_rules == 0)
 384                                         break;
 385                         }
 386                 }
 387         }
 388
 389         if (rule->action == FR_ACT_GOTO)
 390                 ops->nr_goto_rules++;
 391
 392         if (unresolved)
 393                 ops->unresolved_rules++;
 394
 395         if (last)
 396                 list_add_rcu(&rule->list, &last->list);
 397         else
 398                 list_add_rcu(&rule->list, &ops->rules_list);
 399
 400         notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
 401         flush_route_cache(ops);
 402         rules_ops_put(ops);
 403         return 0;
 404
 405 errout_free:
 406         release_net(rule->fr_net);
 407         kfree(rule);
 408 errout:
 409         rules_ops_put(ops);
 410         return err;
 411 }
 412
 413 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 414 {
 415         struct net *net = sock_net(skb->sk);
 416         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 417         struct fib_rules_ops *ops = NULL;
 418         struct fib_rule *rule, *tmp;
 419         struct nlattr *tb[FRA_MAX+1];
 420         int err = -EINVAL;
 421
 422         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 423                 goto errout;
 424
 425         ops = lookup_rules_ops(net, frh->family);
 426         if (ops == NULL) {
 427                 err = -EAFNOSUPPORT;
 428                 goto errout;
 429         }
 430
 431         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 432         if (err < 0)
 433                 goto errout;
 434
 435         err = validate_rulemsg(frh, tb, ops);
 436         if (err < 0)
 437                 goto errout;
 438
 439         list_for_each_entry(rule, &ops->rules_list, list) {
 440                 if (frh->action && (frh->action != rule->action))
 441                         continue;
 442
 443                 if (frh->table && (frh_get_table(frh, tb) != rule->table))
 444                         continue;
 445
 446                 if (tb[FRA_PRIORITY] &&
 447                     (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
 448                         continue;
 449
 450                 if (tb[FRA_IIFNAME] &&
 451                     nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
 452                         continue;
 453
 454                 if (tb[FRA_OIFNAME] &&
 455                     nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
 456                         continue;
 457
 458                 if (tb[FRA_FWMARK] &&
 459                     (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
 460                         continue;
 461
 462                 if (tb[FRA_FWMASK] &&
 463                     (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
 464                         continue;
 465
 466                 if (!ops->compare(rule, frh, tb))
 467                         continue;
 468
 469                 if (rule->flags & FIB_RULE_PERMANENT) {
 470                         err = -EPERM;
 471                         goto errout;
 472                 }
 473
 474                 list_del_rcu(&rule->list);
 475
 476                 if (rule->action == FR_ACT_GOTO)
 477                         ops->nr_goto_rules--;
 478
 479                 /*
 480                  * Check if this rule is a target to any of them. If so,
 481                  * disable them. As this operation is eventually very
 482                  * expensive, it is only performed if goto rules have
 483                  * actually been added.
 484                  */
 485                 if (ops->nr_goto_rules > 0) {
 486                         list_for_each_entry(tmp, &ops->rules_list, list) {
 487                                 if (tmp->ctarget == rule) {
 488                                         rcu_assign_pointer(tmp->ctarget, NULL);
 489                                         ops->unresolved_rules++;
 490                                 }
 491                         }
 492                 }
 493
 494                 synchronize_rcu();
 495                 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
 496                                    NETLINK_CB(skb).pid);
 497                 fib_rule_put(rule);
 498                 flush_route_cache(ops);
 499                 rules_ops_put(ops);
 500                 return 0;
 501         }
 502
 503         err = -ENOENT;
 504 errout:
 505         rules_ops_put(ops);
 506         return err;
 507 }
 508
 509 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
 510                                          struct fib_rule *rule)
 511 {
 512         size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
 513                          + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
 514                          + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
 515                          + nla_total_size(4) /* FRA_PRIORITY */
 516                          + nla_total_size(4) /* FRA_TABLE */
 517                          + nla_total_size(4) /* FRA_FWMARK */
 518                          + nla_total_size(4); /* FRA_FWMASK */
 519
 520         if (ops->nlmsg_payload)
 521                 payload += ops->nlmsg_payload(rule);
 522
 523         return payload;
 524 }
 525
 526 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
 527                             u32 pid, u32 seq, int type, int flags,
 528                             struct fib_rules_ops *ops)
 529 {
 530         struct nlmsghdr *nlh;
 531         struct fib_rule_hdr *frh;
 532
 533         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
 534         if (nlh == NULL)
 535                 return -EMSGSIZE;
 536
 537         frh = nlmsg_data(nlh);
 538         frh->family = ops->family;
 539         frh->table = rule->table;
 540         NLA_PUT_U32(skb, FRA_TABLE, rule->table);
 541         frh->res1 = 0;
 542         frh->res2 = 0;
 543         frh->action = rule->action;
 544         frh->flags = rule->flags;
 545
 546         if (rule->action == FR_ACT_GOTO && rule->ctarget == NULL)
 547                 frh->flags |= FIB_RULE_UNRESOLVED;
 548
 549         if (rule->iifname[0]) {
 550                 NLA_PUT_STRING(skb, FRA_IIFNAME, rule->iifname);
 551
 552                 if (rule->iifindex == -1)
 553                         frh->flags |= FIB_RULE_IIF_DETACHED;
 554         }
 555
 556         if (rule->oifname[0]) {
 557                 NLA_PUT_STRING(skb, FRA_OIFNAME, rule->oifname);
 558
 559                 if (rule->oifindex == -1)
 560                         frh->flags |= FIB_RULE_OIF_DETACHED;
 561         }
 562
 563         if (rule->pref)
 564                 NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
 565
 566         if (rule->mark)
 567                 NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
 568
 569         if (rule->mark_mask || rule->mark)
 570                 NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
 571
 572         if (rule->target)
 573                 NLA_PUT_U32(skb, FRA_GOTO, rule->target);
 574
 575         if (ops->fill(rule, skb, frh) < 0)
 576                 goto nla_put_failure;
 577
 578         return nlmsg_end(skb, nlh);
 579
 580 nla_put_failure:
 581         nlmsg_cancel(skb, nlh);
 582         return -EMSGSIZE;
 583 }
 584
 585 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
 586                       struct fib_rules_ops *ops)
 587 {
 588         int idx = 0;
 589         struct fib_rule *rule;
 590
 591         list_for_each_entry(rule, &ops->rules_list, list) {
 592                 if (idx < cb->args[1])
 593                         goto skip;
 594
 595                 if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
 596                                      cb->nlh->nlmsg_seq, RTM_NEWRULE,
 597                                      NLM_F_MULTI, ops) < 0)
 598                         break;
 599 skip:
 600                 idx++;
 601         }
 602         cb->args[1] = idx;
 603         rules_ops_put(ops);
 604
 605         return skb->len;
 606 }
 607
 608 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 609 {
 610         struct net *net = sock_net(skb->sk);
 611         struct fib_rules_ops *ops;
 612         int idx = 0, family;
 613
 614         family = rtnl_msg_family(cb->nlh);
 615         if (family != AF_UNSPEC) {
 616                 /* Protocol specific dump request */
 617                 ops = lookup_rules_ops(net, family);
 618                 if (ops == NULL)
 619                         return -EAFNOSUPPORT;
 620
 621                 return dump_rules(skb, cb, ops);
 622         }
 623
 624         rcu_read_lock();
 625         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 626                 if (idx < cb->args[0] || !try_module_get(ops->owner))
 627                         goto skip;
 628
 629                 if (dump_rules(skb, cb, ops) < 0)
 630                         break;
 631
 632                 cb->args[1] = 0;
 633 skip:
 634                 idx++;
 635         }
 636         rcu_read_unlock();
 637         cb->args[0] = idx;
 638
 639         return skb->len;
 640 }
 641
 642 static void notify_rule_change(int event, struct fib_rule *rule,
 643                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
 644                                u32 pid)
 645 {
 646         struct net *net;
 647         struct sk_buff *skb;
 648         int err = -ENOBUFS;
 649
 650         net = ops->fro_net;
 651         skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
 652         if (skb == NULL)
 653                 goto errout;
 654
 655         err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
 656         if (err < 0) {
 657                 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
 658                 WARN_ON(err == -EMSGSIZE);
 659                 kfree_skb(skb);
 660                 goto errout;
 661         }
 662
 663         rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
 664         return;
 665 errout:
 666         if (err < 0)
 667                 rtnl_set_sk_err(net, ops->nlgroup, err);
 668 }
 669
 670 static void attach_rules(struct list_head *rules, struct net_device *dev)
 671 {
 672         struct fib_rule *rule;
 673
 674         list_for_each_entry(rule, rules, list) {
 675                 if (rule->iifindex == -1 &&
 676                     strcmp(dev->name, rule->iifname) == 0)
 677                         rule->iifindex = dev->ifindex;
 678                 if (rule->oifindex == -1 &&
 679                     strcmp(dev->name, rule->oifname) == 0)
 680                         rule->oifindex = dev->ifindex;
 681         }
 682 }
 683
 684 static void detach_rules(struct list_head *rules, struct net_device *dev)
 685 {
 686         struct fib_rule *rule;
 687
 688         list_for_each_entry(rule, rules, list) {
 689                 if (rule->iifindex == dev->ifindex)
 690                         rule->iifindex = -1;
 691                 if (rule->oifindex == dev->ifindex)
 692                         rule->oifindex = -1;
 693         }
 694 }
 695
 696
 697 static int fib_rules_event(struct notifier_block *this, unsigned long event,
 698                             void *ptr)
 699 {
 700         struct net_device *dev = ptr;
 701         struct net *net = dev_net(dev);
 702         struct fib_rules_ops *ops;
 703
 704         ASSERT_RTNL();
 705
 706         switch (event) {
 707         case NETDEV_REGISTER:
 708                 list_for_each_entry(ops, &net->rules_ops, list)
 709                         attach_rules(&ops->rules_list, dev);
 710                 break;
 711
 712         case NETDEV_UNREGISTER:
 713                 list_for_each_entry(ops, &net->rules_ops, list)
 714                         detach_rules(&ops->rules_list, dev);
 715                 break;
 716         }
 717
 718         return NOTIFY_DONE;
 719 }
 720
 721 static struct notifier_block fib_rules_notifier = {
 722         .notifier_call = fib_rules_event,
 723 };
 724
 725 static int __net_init fib_rules_net_init(struct net *net)
 726 {
 727         INIT_LIST_HEAD(&net->rules_ops);
 728         spin_lock_init(&net->rules_mod_lock);
 729         return 0;
 730 }
 731
 732 static struct pernet_operations fib_rules_net_ops = {
 733         .init = fib_rules_net_init,
 734 };
 735
 736 static int __init fib_rules_init(void)
 737 {
 738         int err;
 739         rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL);
 740         rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL);
 741         rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule);
 742
 743         err = register_pernet_subsys(&fib_rules_net_ops);
 744         if (err < 0)
 745                 goto fail;
 746
 747         err = register_netdevice_notifier(&fib_rules_notifier);
 748         if (err < 0)
 749                 goto fail_unregister;
 750
 751         return 0;
 752
 753 fail_unregister:
 754         unregister_pernet_subsys(&fib_rules_net_ops);
 755 fail:
 756         rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
 757         rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
 758         rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
 759         return err;
 760 }
 761
 762 subsys_initcall(fib_rules_init);