1bc66592453ca5cdffb71179a8c69eae7c2265c3
[linux-2.6.git] / 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(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);