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TOMOYO Linux Cross Reference
Linux/net/core/fib_rules.c

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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 <linux/module.h>
 16 #include <net/net_namespace.h>
 17 #include <net/sock.h>
 18 #include <net/fib_rules.h>
 19 
 20 int fib_default_rule_add(struct fib_rules_ops *ops,
 21                          u32 pref, u32 table, u32 flags)
 22 {
 23         struct fib_rule *r;
 24 
 25         r = kzalloc(ops->rule_size, GFP_KERNEL);
 26         if (r == NULL)
 27                 return -ENOMEM;
 28 
 29         atomic_set(&r->refcnt, 1);
 30         r->action = FR_ACT_TO_TBL;
 31         r->pref = pref;
 32         r->table = table;
 33         r->flags = flags;
 34         r->fr_net = hold_net(ops->fro_net);
 35 
 36         /* The lock is not required here, the list in unreacheable
 37          * at the moment this function is called */
 38         list_add_tail(&r->list, &ops->rules_list);
 39         return 0;
 40 }
 41 EXPORT_SYMBOL(fib_default_rule_add);
 42 
 43 u32 fib_default_rule_pref(struct fib_rules_ops *ops)
 44 {
 45         struct list_head *pos;
 46         struct fib_rule *rule;
 47 
 48         if (!list_empty(&ops->rules_list)) {
 49                 pos = ops->rules_list.next;
 50                 if (pos->next != &ops->rules_list) {
 51                         rule = list_entry(pos->next, struct fib_rule, list);
 52                         if (rule->pref)
 53                                 return rule->pref - 1;
 54                 }
 55         }
 56 
 57         return 0;
 58 }
 59 EXPORT_SYMBOL(fib_default_rule_pref);
 60 
 61 static void notify_rule_change(int event, struct fib_rule *rule,
 62                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
 63                                u32 pid);
 64 
 65 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
 66 {
 67         struct fib_rules_ops *ops;
 68 
 69         rcu_read_lock();
 70         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 71                 if (ops->family == family) {
 72                         if (!try_module_get(ops->owner))
 73                                 ops = NULL;
 74                         rcu_read_unlock();
 75                         return ops;
 76                 }
 77         }
 78         rcu_read_unlock();
 79 
 80         return NULL;
 81 }
 82 
 83 static void rules_ops_put(struct fib_rules_ops *ops)
 84 {
 85         if (ops)
 86                 module_put(ops->owner);
 87 }
 88 
 89 static void flush_route_cache(struct fib_rules_ops *ops)
 90 {
 91         if (ops->flush_cache)
 92                 ops->flush_cache(ops);
 93 }
 94 
 95 static int __fib_rules_register(struct fib_rules_ops *ops)
 96 {
 97         int err = -EEXIST;
 98         struct fib_rules_ops *o;
 99         struct net *net;
100 
101         net = ops->fro_net;
102 
103         if (ops->rule_size < sizeof(struct fib_rule))
104                 return -EINVAL;
105 
106         if (ops->match == NULL || ops->configure == NULL ||
107             ops->compare == NULL || ops->fill == NULL ||
108             ops->action == NULL)
109                 return -EINVAL;
110 
111         spin_lock(&net->rules_mod_lock);
112         list_for_each_entry(o, &net->rules_ops, list)
113                 if (ops->family == o->family)
114                         goto errout;
115 
116         hold_net(net);
117         list_add_tail_rcu(&ops->list, &net->rules_ops);
118         err = 0;
119 errout:
120         spin_unlock(&net->rules_mod_lock);
121 
122         return err;
123 }
124 
125 struct fib_rules_ops *
126 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
127 {
128         struct fib_rules_ops *ops;
129         int err;
130 
131         ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
132         if (ops == NULL)
133                 return ERR_PTR(-ENOMEM);
134 
135         INIT_LIST_HEAD(&ops->rules_list);
136         ops->fro_net = net;
137 
138         err = __fib_rules_register(ops);
139         if (err) {
140                 kfree(ops);
141                 ops = ERR_PTR(err);
142         }
143 
144         return ops;
145 }
146 EXPORT_SYMBOL_GPL(fib_rules_register);
147 
148 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
149 {
150         struct fib_rule *rule, *tmp;
151 
152         list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
153                 list_del_rcu(&rule->list);
154                 fib_rule_put(rule);
155         }
156 }
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->flowi_iif))
186                 goto out;
187 
188         if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
189                 goto out;
190 
191         if ((rule->mark ^ fl->flowi_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                         if ((arg->flags & FIB_LOOKUP_NOREF) ||
229                             likely(atomic_inc_not_zero(&rule->refcnt))) {
230                                 arg->rule = rule;
231                                 goto out;
232                         }
233                         break;
234                 }
235         }
236 
237         err = -ESRCH;
238 out:
239         rcu_read_unlock();
240 
241         return err;
242 }
243 EXPORT_SYMBOL_GPL(fib_rules_lookup);
244 
245 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
246                             struct fib_rules_ops *ops)
247 {
248         int err = -EINVAL;
249 
250         if (frh->src_len)
251                 if (tb[FRA_SRC] == NULL ||
252                     frh->src_len > (ops->addr_size * 8) ||
253                     nla_len(tb[FRA_SRC]) != ops->addr_size)
254                         goto errout;
255 
256         if (frh->dst_len)
257                 if (tb[FRA_DST] == NULL ||
258                     frh->dst_len > (ops->addr_size * 8) ||
259                     nla_len(tb[FRA_DST]) != ops->addr_size)
260                         goto errout;
261 
262         err = 0;
263 errout:
264         return err;
265 }
266 
267 static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
268 {
269         struct net *net = sock_net(skb->sk);
270         struct fib_rule_hdr *frh = nlmsg_data(nlh);
271         struct fib_rules_ops *ops = NULL;
272         struct fib_rule *rule, *r, *last = NULL;
273         struct nlattr *tb[FRA_MAX+1];
274         int err = -EINVAL, unresolved = 0;
275 
276         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
277                 goto errout;
278 
279         ops = lookup_rules_ops(net, frh->family);
280         if (ops == NULL) {
281                 err = -EAFNOSUPPORT;
282                 goto errout;
283         }
284 
285         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
286         if (err < 0)
287                 goto errout;
288 
289         err = validate_rulemsg(frh, tb, ops);
290         if (err < 0)
291                 goto errout;
292 
293         rule = kzalloc(ops->rule_size, GFP_KERNEL);
294         if (rule == NULL) {
295                 err = -ENOMEM;
296                 goto errout;
297         }
298         rule->fr_net = hold_net(net);
299 
300         if (tb[FRA_PRIORITY])
301                 rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
302 
303         if (tb[FRA_IIFNAME]) {
304                 struct net_device *dev;
305 
306                 rule->iifindex = -1;
307                 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
308                 dev = __dev_get_by_name(net, rule->iifname);
309                 if (dev)
310                         rule->iifindex = dev->ifindex;
311         }
312 
313         if (tb[FRA_OIFNAME]) {
314                 struct net_device *dev;
315 
316                 rule->oifindex = -1;
317                 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
318                 dev = __dev_get_by_name(net, rule->oifname);
319                 if (dev)
320                         rule->oifindex = dev->ifindex;
321         }
322 
323         if (tb[FRA_FWMARK]) {
324                 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
325                 if (rule->mark)
326                         /* compatibility: if the mark value is non-zero all bits
327                          * are compared unless a mask is explicitly specified.
328                          */
329                         rule->mark_mask = 0xFFFFFFFF;
330         }
331 
332         if (tb[FRA_FWMASK])
333                 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
334 
335         rule->action = frh->action;
336         rule->flags = frh->flags;
337         rule->table = frh_get_table(frh, tb);
338 
339         if (!tb[FRA_PRIORITY] && ops->default_pref)
340                 rule->pref = ops->default_pref(ops);
341 
342         err = -EINVAL;
343         if (tb[FRA_GOTO]) {
344                 if (rule->action != FR_ACT_GOTO)
345                         goto errout_free;
346 
347                 rule->target = nla_get_u32(tb[FRA_GOTO]);
348                 /* Backward jumps are prohibited to avoid endless loops */
349                 if (rule->target <= rule->pref)
350                         goto errout_free;
351 
352                 list_for_each_entry(r, &ops->rules_list, list) {
353                         if (r->pref == rule->target) {
354                                 RCU_INIT_POINTER(rule->ctarget, r);
355                                 break;
356                         }
357                 }
358 
359                 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
360                         unresolved = 1;
361         } else if (rule->action == FR_ACT_GOTO)
362                 goto errout_free;
363 
364         err = ops->configure(rule, skb, frh, tb);
365         if (err < 0)
366                 goto errout_free;
367 
368         list_for_each_entry(r, &ops->rules_list, list) {
369                 if (r->pref > rule->pref)
370                         break;
371                 last = r;
372         }
373 
374         fib_rule_get(rule);
375 
376         if (last)
377                 list_add_rcu(&rule->list, &last->list);
378         else
379                 list_add_rcu(&rule->list, &ops->rules_list);
380 
381         if (ops->unresolved_rules) {
382                 /*
383                  * There are unresolved goto rules in the list, check if
384                  * any of them are pointing to this new rule.
385                  */
386                 list_for_each_entry(r, &ops->rules_list, list) {
387                         if (r->action == FR_ACT_GOTO &&
388                             r->target == rule->pref &&
389                             rtnl_dereference(r->ctarget) == NULL) {
390                                 rcu_assign_pointer(r->ctarget, rule);
391                                 if (--ops->unresolved_rules == 0)
392                                         break;
393                         }
394                 }
395         }
396 
397         if (rule->action == FR_ACT_GOTO)
398                 ops->nr_goto_rules++;
399 
400         if (unresolved)
401                 ops->unresolved_rules++;
402 
403         notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
404         flush_route_cache(ops);
405         rules_ops_put(ops);
406         return 0;
407 
408 errout_free:
409         release_net(rule->fr_net);
410         kfree(rule);
411 errout:
412         rules_ops_put(ops);
413         return err;
414 }
415 
416 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
417 {
418         struct net *net = sock_net(skb->sk);
419         struct fib_rule_hdr *frh = nlmsg_data(nlh);
420         struct fib_rules_ops *ops = NULL;
421         struct fib_rule *rule, *tmp;
422         struct nlattr *tb[FRA_MAX+1];
423         int err = -EINVAL;
424 
425         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
426                 goto errout;
427 
428         ops = lookup_rules_ops(net, frh->family);
429         if (ops == NULL) {
430                 err = -EAFNOSUPPORT;
431                 goto errout;
432         }
433 
434         err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
435         if (err < 0)
436                 goto errout;
437 
438         err = validate_rulemsg(frh, tb, ops);
439         if (err < 0)
440                 goto errout;
441 
442         list_for_each_entry(rule, &ops->rules_list, list) {
443                 if (frh->action && (frh->action != rule->action))
444                         continue;
445 
446                 if (frh_get_table(frh, tb) &&
447                     (frh_get_table(frh, tb) != rule->table))
448                         continue;
449 
450                 if (tb[FRA_PRIORITY] &&
451                     (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
452                         continue;
453 
454                 if (tb[FRA_IIFNAME] &&
455                     nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
456                         continue;
457 
458                 if (tb[FRA_OIFNAME] &&
459                     nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
460                         continue;
461 
462                 if (tb[FRA_FWMARK] &&
463                     (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
464                         continue;
465 
466                 if (tb[FRA_FWMASK] &&
467                     (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
468                         continue;
469 
470                 if (!ops->compare(rule, frh, tb))
471                         continue;
472 
473                 if (rule->flags & FIB_RULE_PERMANENT) {
474                         err = -EPERM;
475                         goto errout;
476                 }
477 
478                 list_del_rcu(&rule->list);
479 
480                 if (rule->action == FR_ACT_GOTO) {
481                         ops->nr_goto_rules--;
482                         if (rtnl_dereference(rule->ctarget) == NULL)
483                                 ops->unresolved_rules--;
484                 }
485 
486                 /*
487                  * Check if this rule is a target to any of them. If so,
488                  * disable them. As this operation is eventually very
489                  * expensive, it is only performed if goto rules have
490                  * actually been added.
491                  */
492                 if (ops->nr_goto_rules > 0) {
493                         list_for_each_entry(tmp, &ops->rules_list, list) {
494                                 if (rtnl_dereference(tmp->ctarget) == rule) {
495                                         RCU_INIT_POINTER(tmp->ctarget, NULL);
496                                         ops->unresolved_rules++;
497                                 }
498                         }
499                 }
500 
501                 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
502                                    NETLINK_CB(skb).pid);
503                 fib_rule_put(rule);
504                 flush_route_cache(ops);
505                 rules_ops_put(ops);
506                 return 0;
507         }
508 
509         err = -ENOENT;
510 errout:
511         rules_ops_put(ops);
512         return err;
513 }
514 
515 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
516                                          struct fib_rule *rule)
517 {
518         size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
519                          + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
520                          + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
521                          + nla_total_size(4) /* FRA_PRIORITY */
522                          + nla_total_size(4) /* FRA_TABLE */
523                          + nla_total_size(4) /* FRA_FWMARK */
524                          + nla_total_size(4); /* FRA_FWMASK */
525 
526         if (ops->nlmsg_payload)
527                 payload += ops->nlmsg_payload(rule);
528 
529         return payload;
530 }
531 
532 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
533                             u32 pid, u32 seq, int type, int flags,
534                             struct fib_rules_ops *ops)
535 {
536         struct nlmsghdr *nlh;
537         struct fib_rule_hdr *frh;
538 
539         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
540         if (nlh == NULL)
541                 return -EMSGSIZE;
542 
543         frh = nlmsg_data(nlh);
544         frh->family = ops->family;
545         frh->table = rule->table;
546         NLA_PUT_U32(skb, FRA_TABLE, rule->table);
547         frh->res1 = 0;
548         frh->res2 = 0;
549         frh->action = rule->action;
550         frh->flags = rule->flags;
551 
552         if (rule->action == FR_ACT_GOTO &&
553             rcu_access_pointer(rule->ctarget) == NULL)
554                 frh->flags |= FIB_RULE_UNRESOLVED;
555 
556         if (rule->iifname[0]) {
557                 NLA_PUT_STRING(skb, FRA_IIFNAME, rule->iifname);
558 
559                 if (rule->iifindex == -1)
560                         frh->flags |= FIB_RULE_IIF_DETACHED;
561         }
562 
563         if (rule->oifname[0]) {
564                 NLA_PUT_STRING(skb, FRA_OIFNAME, rule->oifname);
565 
566                 if (rule->oifindex == -1)
567                         frh->flags |= FIB_RULE_OIF_DETACHED;
568         }
569 
570         if (rule->pref)
571                 NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
572 
573         if (rule->mark)
574                 NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
575 
576         if (rule->mark_mask || rule->mark)
577                 NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
578 
579         if (rule->target)
580                 NLA_PUT_U32(skb, FRA_GOTO, rule->target);
581 
582         if (ops->fill(rule, skb, frh) < 0)
583                 goto nla_put_failure;
584 
585         return nlmsg_end(skb, nlh);
586 
587 nla_put_failure:
588         nlmsg_cancel(skb, nlh);
589         return -EMSGSIZE;
590 }
591 
592 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
593                       struct fib_rules_ops *ops)
594 {
595         int idx = 0;
596         struct fib_rule *rule;
597         int err = 0;
598 
599         rcu_read_lock();
600         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
601                 if (idx < cb->args[1])
602                         goto skip;
603 
604                 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
605                                        cb->nlh->nlmsg_seq, RTM_NEWRULE,
606                                        NLM_F_MULTI, ops);
607                 if (err < 0)
608                         break;
609 skip:
610                 idx++;
611         }
612         rcu_read_unlock();
613         cb->args[1] = idx;
614         rules_ops_put(ops);
615 
616         return err;
617 }
618 
619 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
620 {
621         struct net *net = sock_net(skb->sk);
622         struct fib_rules_ops *ops;
623         int idx = 0, family;
624 
625         family = rtnl_msg_family(cb->nlh);
626         if (family != AF_UNSPEC) {
627                 /* Protocol specific dump request */
628                 ops = lookup_rules_ops(net, family);
629                 if (ops == NULL)
630                         return -EAFNOSUPPORT;
631 
632                 dump_rules(skb, cb, ops);
633 
634                 return skb->len;
635         }
636 
637         rcu_read_lock();
638         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
639                 if (idx < cb->args[0] || !try_module_get(ops->owner))
640                         goto skip;
641 
642                 if (dump_rules(skb, cb, ops) < 0)
643                         break;
644 
645                 cb->args[1] = 0;
646 skip:
647                 idx++;
648         }
649         rcu_read_unlock();
650         cb->args[0] = idx;
651 
652         return skb->len;
653 }
654 
655 static void notify_rule_change(int event, struct fib_rule *rule,
656                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
657                                u32 pid)
658 {
659         struct net *net;
660         struct sk_buff *skb;
661         int err = -ENOBUFS;
662 
663         net = ops->fro_net;
664         skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
665         if (skb == NULL)
666                 goto errout;
667 
668         err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
669         if (err < 0) {
670                 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
671                 WARN_ON(err == -EMSGSIZE);
672                 kfree_skb(skb);
673                 goto errout;
674         }
675 
676         rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
677         return;
678 errout:
679         if (err < 0)
680                 rtnl_set_sk_err(net, ops->nlgroup, err);
681 }
682 
683 static void attach_rules(struct list_head *rules, struct net_device *dev)
684 {
685         struct fib_rule *rule;
686 
687         list_for_each_entry(rule, rules, list) {
688                 if (rule->iifindex == -1 &&
689                     strcmp(dev->name, rule->iifname) == 0)
690                         rule->iifindex = dev->ifindex;
691                 if (rule->oifindex == -1 &&
692                     strcmp(dev->name, rule->oifname) == 0)
693                         rule->oifindex = dev->ifindex;
694         }
695 }
696 
697 static void detach_rules(struct list_head *rules, struct net_device *dev)
698 {
699         struct fib_rule *rule;
700 
701         list_for_each_entry(rule, rules, list) {
702                 if (rule->iifindex == dev->ifindex)
703                         rule->iifindex = -1;
704                 if (rule->oifindex == dev->ifindex)
705                         rule->oifindex = -1;
706         }
707 }
708 
709 
710 static int fib_rules_event(struct notifier_block *this, unsigned long event,
711                             void *ptr)
712 {
713         struct net_device *dev = ptr;
714         struct net *net = dev_net(dev);
715         struct fib_rules_ops *ops;
716 
717         ASSERT_RTNL();
718 
719         switch (event) {
720         case NETDEV_REGISTER:
721                 list_for_each_entry(ops, &net->rules_ops, list)
722                         attach_rules(&ops->rules_list, dev);
723                 break;
724 
725         case NETDEV_CHANGENAME:
726                 list_for_each_entry(ops, &net->rules_ops, list) {
727                         detach_rules(&ops->rules_list, dev);
728                         attach_rules(&ops->rules_list, dev);
729                 }
730                 break;
731 
732         case NETDEV_UNREGISTER:
733                 list_for_each_entry(ops, &net->rules_ops, list)
734                         detach_rules(&ops->rules_list, dev);
735                 break;
736         }
737 
738         return NOTIFY_DONE;
739 }
740 
741 static struct notifier_block fib_rules_notifier = {
742         .notifier_call = fib_rules_event,
743 };
744 
745 static int __net_init fib_rules_net_init(struct net *net)
746 {
747         INIT_LIST_HEAD(&net->rules_ops);
748         spin_lock_init(&net->rules_mod_lock);
749         return 0;
750 }
751 
752 static struct pernet_operations fib_rules_net_ops = {
753         .init = fib_rules_net_init,
754 };
755 
756 static int __init fib_rules_init(void)
757 {
758         int err;
759         rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL);
760         rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL);
761         rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL);
762 
763         err = register_pernet_subsys(&fib_rules_net_ops);
764         if (err < 0)
765                 goto fail;
766 
767         err = register_netdevice_notifier(&fib_rules_notifier);
768         if (err < 0)
769                 goto fail_unregister;
770 
771         return 0;
772 
773 fail_unregister:
774         unregister_pernet_subsys(&fib_rules_net_ops);
775 fail:
776         rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
777         rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
778         rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
779         return err;
780 }
781 
782 subsys_initcall(fib_rules_init);
783 

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