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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#include <net/ip_tunnels.h>
20
21int fib_default_rule_add(struct fib_rules_ops *ops,
22 u32 pref, u32 table, u32 flags)
23{
24 struct fib_rule *r;
25
26 r = kzalloc(ops->rule_size, GFP_KERNEL);
27 if (r == NULL)
28 return -ENOMEM;
29
30 atomic_set(&r->refcnt, 1);
31 r->action = FR_ACT_TO_TBL;
32 r->pref = pref;
33 r->table = table;
34 r->flags = flags;
35 r->fr_net = ops->fro_net;
36
37 r->suppress_prefixlen = -1;
38 r->suppress_ifgroup = -1;
39
40 /* The lock is not required here, the list in unreacheable
41 * at the moment this function is called */
42 list_add_tail(&r->list, &ops->rules_list);
43 return 0;
44}
45EXPORT_SYMBOL(fib_default_rule_add);
46
47static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
48{
49 struct list_head *pos;
50 struct fib_rule *rule;
51
52 if (!list_empty(&ops->rules_list)) {
53 pos = ops->rules_list.next;
54 if (pos->next != &ops->rules_list) {
55 rule = list_entry(pos->next, struct fib_rule, list);
56 if (rule->pref)
57 return rule->pref - 1;
58 }
59 }
60
61 return 0;
62}
63
64static void notify_rule_change(int event, struct fib_rule *rule,
65 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
66 u32 pid);
67
68static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
69{
70 struct fib_rules_ops *ops;
71
72 rcu_read_lock();
73 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
74 if (ops->family == family) {
75 if (!try_module_get(ops->owner))
76 ops = NULL;
77 rcu_read_unlock();
78 return ops;
79 }
80 }
81 rcu_read_unlock();
82
83 return NULL;
84}
85
86static void rules_ops_put(struct fib_rules_ops *ops)
87{
88 if (ops)
89 module_put(ops->owner);
90}
91
92static void flush_route_cache(struct fib_rules_ops *ops)
93{
94 if (ops->flush_cache)
95 ops->flush_cache(ops);
96}
97
98static int __fib_rules_register(struct fib_rules_ops *ops)
99{
100 int err = -EEXIST;
101 struct fib_rules_ops *o;
102 struct net *net;
103
104 net = ops->fro_net;
105
106 if (ops->rule_size < sizeof(struct fib_rule))
107 return -EINVAL;
108
109 if (ops->match == NULL || ops->configure == NULL ||
110 ops->compare == NULL || ops->fill == NULL ||
111 ops->action == NULL)
112 return -EINVAL;
113
114 spin_lock(&net->rules_mod_lock);
115 list_for_each_entry(o, &net->rules_ops, list)
116 if (ops->family == o->family)
117 goto errout;
118
119 list_add_tail_rcu(&ops->list, &net->rules_ops);
120 err = 0;
121errout:
122 spin_unlock(&net->rules_mod_lock);
123
124 return err;
125}
126
127struct fib_rules_ops *
128fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
129{
130 struct fib_rules_ops *ops;
131 int err;
132
133 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
134 if (ops == NULL)
135 return ERR_PTR(-ENOMEM);
136
137 INIT_LIST_HEAD(&ops->rules_list);
138 ops->fro_net = net;
139
140 err = __fib_rules_register(ops);
141 if (err) {
142 kfree(ops);
143 ops = ERR_PTR(err);
144 }
145
146 return ops;
147}
148EXPORT_SYMBOL_GPL(fib_rules_register);
149
150static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
151{
152 struct fib_rule *rule, *tmp;
153
154 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
155 list_del_rcu(&rule->list);
156 if (ops->delete)
157 ops->delete(rule);
158 fib_rule_put(rule);
159 }
160}
161
162void fib_rules_unregister(struct fib_rules_ops *ops)
163{
164 struct net *net = ops->fro_net;
165
166 spin_lock(&net->rules_mod_lock);
167 list_del_rcu(&ops->list);
168 spin_unlock(&net->rules_mod_lock);
169
170 fib_rules_cleanup_ops(ops);
171 kfree_rcu(ops, rcu);
172}
173EXPORT_SYMBOL_GPL(fib_rules_unregister);
174
175static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
176 struct flowi *fl, int flags)
177{
178 int ret = 0;
179
180 if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
181 goto out;
182
183 if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
184 goto out;
185
186 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
187 goto out;
188
189 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
190 goto out;
191
192 ret = ops->match(rule, fl, flags);
193out:
194 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
195}
196
197int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
198 int flags, struct fib_lookup_arg *arg)
199{
200 struct fib_rule *rule;
201 int err;
202
203 rcu_read_lock();
204
205 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
206jumped:
207 if (!fib_rule_match(rule, ops, fl, flags))
208 continue;
209
210 if (rule->action == FR_ACT_GOTO) {
211 struct fib_rule *target;
212
213 target = rcu_dereference(rule->ctarget);
214 if (target == NULL) {
215 continue;
216 } else {
217 rule = target;
218 goto jumped;
219 }
220 } else if (rule->action == FR_ACT_NOP)
221 continue;
222 else
223 err = ops->action(rule, fl, flags, arg);
224
225 if (!err && ops->suppress && ops->suppress(rule, arg))
226 continue;
227
228 if (err != -EAGAIN) {
229 if ((arg->flags & FIB_LOOKUP_NOREF) ||
230 likely(atomic_inc_not_zero(&rule->refcnt))) {
231 arg->rule = rule;
232 goto out;
233 }
234 break;
235 }
236 }
237
238 err = -ESRCH;
239out:
240 rcu_read_unlock();
241
242 return err;
243}
244EXPORT_SYMBOL_GPL(fib_rules_lookup);
245
246static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
247 struct fib_rules_ops *ops)
248{
249 int err = -EINVAL;
250
251 if (frh->src_len)
252 if (tb[FRA_SRC] == NULL ||
253 frh->src_len > (ops->addr_size * 8) ||
254 nla_len(tb[FRA_SRC]) != ops->addr_size)
255 goto errout;
256
257 if (frh->dst_len)
258 if (tb[FRA_DST] == NULL ||
259 frh->dst_len > (ops->addr_size * 8) ||
260 nla_len(tb[FRA_DST]) != ops->addr_size)
261 goto errout;
262
263 err = 0;
264errout:
265 return err;
266}
267
268static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh)
269{
270 struct net *net = sock_net(skb->sk);
271 struct fib_rule_hdr *frh = nlmsg_data(nlh);
272 struct fib_rules_ops *ops = NULL;
273 struct fib_rule *rule, *r, *last = NULL;
274 struct nlattr *tb[FRA_MAX+1];
275 int err = -EINVAL, unresolved = 0;
276
277 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
278 goto errout;
279
280 ops = lookup_rules_ops(net, frh->family);
281 if (ops == NULL) {
282 err = -EAFNOSUPPORT;
283 goto errout;
284 }
285
286 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
287 if (err < 0)
288 goto errout;
289
290 err = validate_rulemsg(frh, tb, ops);
291 if (err < 0)
292 goto errout;
293
294 rule = kzalloc(ops->rule_size, GFP_KERNEL);
295 if (rule == NULL) {
296 err = -ENOMEM;
297 goto errout;
298 }
299 rule->fr_net = net;
300
301 rule->pref = tb[FRA_PRIORITY] ? nla_get_u32(tb[FRA_PRIORITY])
302 : fib_default_rule_pref(ops);
303
304 if (tb[FRA_IIFNAME]) {
305 struct net_device *dev;
306
307 rule->iifindex = -1;
308 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
309 dev = __dev_get_by_name(net, rule->iifname);
310 if (dev)
311 rule->iifindex = dev->ifindex;
312 }
313
314 if (tb[FRA_OIFNAME]) {
315 struct net_device *dev;
316
317 rule->oifindex = -1;
318 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
319 dev = __dev_get_by_name(net, rule->oifname);
320 if (dev)
321 rule->oifindex = dev->ifindex;
322 }
323
324 if (tb[FRA_FWMARK]) {
325 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
326 if (rule->mark)
327 /* compatibility: if the mark value is non-zero all bits
328 * are compared unless a mask is explicitly specified.
329 */
330 rule->mark_mask = 0xFFFFFFFF;
331 }
332
333 if (tb[FRA_FWMASK])
334 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
335
336 if (tb[FRA_TUN_ID])
337 rule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
338
339 rule->action = frh->action;
340 rule->flags = frh->flags;
341 rule->table = frh_get_table(frh, tb);
342 if (tb[FRA_SUPPRESS_PREFIXLEN])
343 rule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
344 else
345 rule->suppress_prefixlen = -1;
346
347 if (tb[FRA_SUPPRESS_IFGROUP])
348 rule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
349 else
350 rule->suppress_ifgroup = -1;
351
352 err = -EINVAL;
353 if (tb[FRA_GOTO]) {
354 if (rule->action != FR_ACT_GOTO)
355 goto errout_free;
356
357 rule->target = nla_get_u32(tb[FRA_GOTO]);
358 /* Backward jumps are prohibited to avoid endless loops */
359 if (rule->target <= rule->pref)
360 goto errout_free;
361
362 list_for_each_entry(r, &ops->rules_list, list) {
363 if (r->pref == rule->target) {
364 RCU_INIT_POINTER(rule->ctarget, r);
365 break;
366 }
367 }
368
369 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
370 unresolved = 1;
371 } else if (rule->action == FR_ACT_GOTO)
372 goto errout_free;
373
374 err = ops->configure(rule, skb, frh, tb);
375 if (err < 0)
376 goto errout_free;
377
378 list_for_each_entry(r, &ops->rules_list, list) {
379 if (r->pref > rule->pref)
380 break;
381 last = r;
382 }
383
384 fib_rule_get(rule);
385
386 if (last)
387 list_add_rcu(&rule->list, &last->list);
388 else
389 list_add_rcu(&rule->list, &ops->rules_list);
390
391 if (ops->unresolved_rules) {
392 /*
393 * There are unresolved goto rules in the list, check if
394 * any of them are pointing to this new rule.
395 */
396 list_for_each_entry(r, &ops->rules_list, list) {
397 if (r->action == FR_ACT_GOTO &&
398 r->target == rule->pref &&
399 rtnl_dereference(r->ctarget) == NULL) {
400 rcu_assign_pointer(r->ctarget, rule);
401 if (--ops->unresolved_rules == 0)
402 break;
403 }
404 }
405 }
406
407 if (rule->action == FR_ACT_GOTO)
408 ops->nr_goto_rules++;
409
410 if (unresolved)
411 ops->unresolved_rules++;
412
413 if (rule->tun_id)
414 ip_tunnel_need_metadata();
415
416 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
417 flush_route_cache(ops);
418 rules_ops_put(ops);
419 return 0;
420
421errout_free:
422 kfree(rule);
423errout:
424 rules_ops_put(ops);
425 return err;
426}
427
428static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh)
429{
430 struct net *net = sock_net(skb->sk);
431 struct fib_rule_hdr *frh = nlmsg_data(nlh);
432 struct fib_rules_ops *ops = NULL;
433 struct fib_rule *rule, *tmp;
434 struct nlattr *tb[FRA_MAX+1];
435 int err = -EINVAL;
436
437 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
438 goto errout;
439
440 ops = lookup_rules_ops(net, frh->family);
441 if (ops == NULL) {
442 err = -EAFNOSUPPORT;
443 goto errout;
444 }
445
446 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
447 if (err < 0)
448 goto errout;
449
450 err = validate_rulemsg(frh, tb, ops);
451 if (err < 0)
452 goto errout;
453
454 list_for_each_entry(rule, &ops->rules_list, list) {
455 if (frh->action && (frh->action != rule->action))
456 continue;
457
458 if (frh_get_table(frh, tb) &&
459 (frh_get_table(frh, tb) != rule->table))
460 continue;
461
462 if (tb[FRA_PRIORITY] &&
463 (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
464 continue;
465
466 if (tb[FRA_IIFNAME] &&
467 nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
468 continue;
469
470 if (tb[FRA_OIFNAME] &&
471 nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
472 continue;
473
474 if (tb[FRA_FWMARK] &&
475 (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
476 continue;
477
478 if (tb[FRA_FWMASK] &&
479 (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
480 continue;
481
482 if (tb[FRA_TUN_ID] &&
483 (rule->tun_id != nla_get_be64(tb[FRA_TUN_ID])))
484 continue;
485
486 if (!ops->compare(rule, frh, tb))
487 continue;
488
489 if (rule->flags & FIB_RULE_PERMANENT) {
490 err = -EPERM;
491 goto errout;
492 }
493
494 if (ops->delete) {
495 err = ops->delete(rule);
496 if (err)
497 goto errout;
498 }
499
500 if (rule->tun_id)
501 ip_tunnel_unneed_metadata();
502
503 list_del_rcu(&rule->list);
504
505 if (rule->action == FR_ACT_GOTO) {
506 ops->nr_goto_rules--;
507 if (rtnl_dereference(rule->ctarget) == NULL)
508 ops->unresolved_rules--;
509 }
510
511 /*
512 * Check if this rule is a target to any of them. If so,
513 * disable them. As this operation is eventually very
514 * expensive, it is only performed if goto rules have
515 * actually been added.
516 */
517 if (ops->nr_goto_rules > 0) {
518 list_for_each_entry(tmp, &ops->rules_list, list) {
519 if (rtnl_dereference(tmp->ctarget) == rule) {
520 RCU_INIT_POINTER(tmp->ctarget, NULL);
521 ops->unresolved_rules++;
522 }
523 }
524 }
525
526 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
527 NETLINK_CB(skb).portid);
528 fib_rule_put(rule);
529 flush_route_cache(ops);
530 rules_ops_put(ops);
531 return 0;
532 }
533
534 err = -ENOENT;
535errout:
536 rules_ops_put(ops);
537 return err;
538}
539
540static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
541 struct fib_rule *rule)
542{
543 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
544 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
545 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
546 + nla_total_size(4) /* FRA_PRIORITY */
547 + nla_total_size(4) /* FRA_TABLE */
548 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
549 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
550 + nla_total_size(4) /* FRA_FWMARK */
551 + nla_total_size(4) /* FRA_FWMASK */
552 + nla_total_size(8); /* FRA_TUN_ID */
553
554 if (ops->nlmsg_payload)
555 payload += ops->nlmsg_payload(rule);
556
557 return payload;
558}
559
560static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
561 u32 pid, u32 seq, int type, int flags,
562 struct fib_rules_ops *ops)
563{
564 struct nlmsghdr *nlh;
565 struct fib_rule_hdr *frh;
566
567 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
568 if (nlh == NULL)
569 return -EMSGSIZE;
570
571 frh = nlmsg_data(nlh);
572 frh->family = ops->family;
573 frh->table = rule->table;
574 if (nla_put_u32(skb, FRA_TABLE, rule->table))
575 goto nla_put_failure;
576 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
577 goto nla_put_failure;
578 frh->res1 = 0;
579 frh->res2 = 0;
580 frh->action = rule->action;
581 frh->flags = rule->flags;
582
583 if (rule->action == FR_ACT_GOTO &&
584 rcu_access_pointer(rule->ctarget) == NULL)
585 frh->flags |= FIB_RULE_UNRESOLVED;
586
587 if (rule->iifname[0]) {
588 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
589 goto nla_put_failure;
590 if (rule->iifindex == -1)
591 frh->flags |= FIB_RULE_IIF_DETACHED;
592 }
593
594 if (rule->oifname[0]) {
595 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
596 goto nla_put_failure;
597 if (rule->oifindex == -1)
598 frh->flags |= FIB_RULE_OIF_DETACHED;
599 }
600
601 if ((rule->pref &&
602 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
603 (rule->mark &&
604 nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
605 ((rule->mark_mask || rule->mark) &&
606 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
607 (rule->target &&
608 nla_put_u32(skb, FRA_GOTO, rule->target)) ||
609 (rule->tun_id &&
610 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id)))
611 goto nla_put_failure;
612
613 if (rule->suppress_ifgroup != -1) {
614 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
615 goto nla_put_failure;
616 }
617
618 if (ops->fill(rule, skb, frh) < 0)
619 goto nla_put_failure;
620
621 nlmsg_end(skb, nlh);
622 return 0;
623
624nla_put_failure:
625 nlmsg_cancel(skb, nlh);
626 return -EMSGSIZE;
627}
628
629static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
630 struct fib_rules_ops *ops)
631{
632 int idx = 0;
633 struct fib_rule *rule;
634 int err = 0;
635
636 rcu_read_lock();
637 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
638 if (idx < cb->args[1])
639 goto skip;
640
641 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
642 cb->nlh->nlmsg_seq, RTM_NEWRULE,
643 NLM_F_MULTI, ops);
644 if (err)
645 break;
646skip:
647 idx++;
648 }
649 rcu_read_unlock();
650 cb->args[1] = idx;
651 rules_ops_put(ops);
652
653 return err;
654}
655
656static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
657{
658 struct net *net = sock_net(skb->sk);
659 struct fib_rules_ops *ops;
660 int idx = 0, family;
661
662 family = rtnl_msg_family(cb->nlh);
663 if (family != AF_UNSPEC) {
664 /* Protocol specific dump request */
665 ops = lookup_rules_ops(net, family);
666 if (ops == NULL)
667 return -EAFNOSUPPORT;
668
669 dump_rules(skb, cb, ops);
670
671 return skb->len;
672 }
673
674 rcu_read_lock();
675 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
676 if (idx < cb->args[0] || !try_module_get(ops->owner))
677 goto skip;
678
679 if (dump_rules(skb, cb, ops) < 0)
680 break;
681
682 cb->args[1] = 0;
683skip:
684 idx++;
685 }
686 rcu_read_unlock();
687 cb->args[0] = idx;
688
689 return skb->len;
690}
691
692static void notify_rule_change(int event, struct fib_rule *rule,
693 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
694 u32 pid)
695{
696 struct net *net;
697 struct sk_buff *skb;
698 int err = -ENOBUFS;
699
700 net = ops->fro_net;
701 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
702 if (skb == NULL)
703 goto errout;
704
705 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
706 if (err < 0) {
707 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
708 WARN_ON(err == -EMSGSIZE);
709 kfree_skb(skb);
710 goto errout;
711 }
712
713 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
714 return;
715errout:
716 if (err < 0)
717 rtnl_set_sk_err(net, ops->nlgroup, err);
718}
719
720static void attach_rules(struct list_head *rules, struct net_device *dev)
721{
722 struct fib_rule *rule;
723
724 list_for_each_entry(rule, rules, list) {
725 if (rule->iifindex == -1 &&
726 strcmp(dev->name, rule->iifname) == 0)
727 rule->iifindex = dev->ifindex;
728 if (rule->oifindex == -1 &&
729 strcmp(dev->name, rule->oifname) == 0)
730 rule->oifindex = dev->ifindex;
731 }
732}
733
734static void detach_rules(struct list_head *rules, struct net_device *dev)
735{
736 struct fib_rule *rule;
737
738 list_for_each_entry(rule, rules, list) {
739 if (rule->iifindex == dev->ifindex)
740 rule->iifindex = -1;
741 if (rule->oifindex == dev->ifindex)
742 rule->oifindex = -1;
743 }
744}
745
746
747static int fib_rules_event(struct notifier_block *this, unsigned long event,
748 void *ptr)
749{
750 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
751 struct net *net = dev_net(dev);
752 struct fib_rules_ops *ops;
753
754 ASSERT_RTNL();
755
756 switch (event) {
757 case NETDEV_REGISTER:
758 list_for_each_entry(ops, &net->rules_ops, list)
759 attach_rules(&ops->rules_list, dev);
760 break;
761
762 case NETDEV_CHANGENAME:
763 list_for_each_entry(ops, &net->rules_ops, list) {
764 detach_rules(&ops->rules_list, dev);
765 attach_rules(&ops->rules_list, dev);
766 }
767 break;
768
769 case NETDEV_UNREGISTER:
770 list_for_each_entry(ops, &net->rules_ops, list)
771 detach_rules(&ops->rules_list, dev);
772 break;
773 }
774
775 return NOTIFY_DONE;
776}
777
778static struct notifier_block fib_rules_notifier = {
779 .notifier_call = fib_rules_event,
780};
781
782static int __net_init fib_rules_net_init(struct net *net)
783{
784 INIT_LIST_HEAD(&net->rules_ops);
785 spin_lock_init(&net->rules_mod_lock);
786 return 0;
787}
788
789static struct pernet_operations fib_rules_net_ops = {
790 .init = fib_rules_net_init,
791};
792
793static int __init fib_rules_init(void)
794{
795 int err;
796 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL);
797 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL);
798 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL);
799
800 err = register_pernet_subsys(&fib_rules_net_ops);
801 if (err < 0)
802 goto fail;
803
804 err = register_netdevice_notifier(&fib_rules_notifier);
805 if (err < 0)
806 goto fail_unregister;
807
808 return 0;
809
810fail_unregister:
811 unregister_pernet_subsys(&fib_rules_net_ops);
812fail:
813 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
814 rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
815 rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
816 return err;
817}
818
819subsys_initcall(fib_rules_init);
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
19int 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}
40EXPORT_SYMBOL(fib_default_rule_add);
41
42u32 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}
58EXPORT_SYMBOL(fib_default_rule_pref);
59
60static void notify_rule_change(int event, struct fib_rule *rule,
61 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
62 u32 pid);
63
64static 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
82static void rules_ops_put(struct fib_rules_ops *ops)
83{
84 if (ops)
85 module_put(ops->owner);
86}
87
88static void flush_route_cache(struct fib_rules_ops *ops)
89{
90 if (ops->flush_cache)
91 ops->flush_cache(ops);
92}
93
94static 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;
118errout:
119 spin_unlock(&net->rules_mod_lock);
120
121 return err;
122}
123
124struct fib_rules_ops *
125fib_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}
145EXPORT_SYMBOL_GPL(fib_rules_register);
146
147static 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
157static void fib_rules_put_rcu(struct rcu_head *head)
158{
159 struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu);
160 struct net *net = ops->fro_net;
161
162 release_net(net);
163 kfree(ops);
164}
165
166void fib_rules_unregister(struct fib_rules_ops *ops)
167{
168 struct net *net = ops->fro_net;
169
170 spin_lock(&net->rules_mod_lock);
171 list_del_rcu(&ops->list);
172 fib_rules_cleanup_ops(ops);
173 spin_unlock(&net->rules_mod_lock);
174
175 call_rcu(&ops->rcu, fib_rules_put_rcu);
176}
177EXPORT_SYMBOL_GPL(fib_rules_unregister);
178
179static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
180 struct flowi *fl, int flags)
181{
182 int ret = 0;
183
184 if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
185 goto out;
186
187 if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
188 goto out;
189
190 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
191 goto out;
192
193 ret = ops->match(rule, fl, flags);
194out:
195 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
196}
197
198int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
199 int flags, struct fib_lookup_arg *arg)
200{
201 struct fib_rule *rule;
202 int err;
203
204 rcu_read_lock();
205
206 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
207jumped:
208 if (!fib_rule_match(rule, ops, fl, flags))
209 continue;
210
211 if (rule->action == FR_ACT_GOTO) {
212 struct fib_rule *target;
213
214 target = rcu_dereference(rule->ctarget);
215 if (target == NULL) {
216 continue;
217 } else {
218 rule = target;
219 goto jumped;
220 }
221 } else if (rule->action == FR_ACT_NOP)
222 continue;
223 else
224 err = ops->action(rule, fl, flags, arg);
225
226 if (err != -EAGAIN) {
227 if ((arg->flags & FIB_LOOKUP_NOREF) ||
228 likely(atomic_inc_not_zero(&rule->refcnt))) {
229 arg->rule = rule;
230 goto out;
231 }
232 break;
233 }
234 }
235
236 err = -ESRCH;
237out:
238 rcu_read_unlock();
239
240 return err;
241}
242EXPORT_SYMBOL_GPL(fib_rules_lookup);
243
244static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
245 struct fib_rules_ops *ops)
246{
247 int err = -EINVAL;
248
249 if (frh->src_len)
250 if (tb[FRA_SRC] == NULL ||
251 frh->src_len > (ops->addr_size * 8) ||
252 nla_len(tb[FRA_SRC]) != ops->addr_size)
253 goto errout;
254
255 if (frh->dst_len)
256 if (tb[FRA_DST] == NULL ||
257 frh->dst_len > (ops->addr_size * 8) ||
258 nla_len(tb[FRA_DST]) != ops->addr_size)
259 goto errout;
260
261 err = 0;
262errout:
263 return err;
264}
265
266static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
267{
268 struct net *net = sock_net(skb->sk);
269 struct fib_rule_hdr *frh = nlmsg_data(nlh);
270 struct fib_rules_ops *ops = NULL;
271 struct fib_rule *rule, *r, *last = NULL;
272 struct nlattr *tb[FRA_MAX+1];
273 int err = -EINVAL, unresolved = 0;
274
275 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
276 goto errout;
277
278 ops = lookup_rules_ops(net, frh->family);
279 if (ops == NULL) {
280 err = -EAFNOSUPPORT;
281 goto errout;
282 }
283
284 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
285 if (err < 0)
286 goto errout;
287
288 err = validate_rulemsg(frh, tb, ops);
289 if (err < 0)
290 goto errout;
291
292 rule = kzalloc(ops->rule_size, GFP_KERNEL);
293 if (rule == NULL) {
294 err = -ENOMEM;
295 goto errout;
296 }
297 rule->fr_net = hold_net(net);
298
299 if (tb[FRA_PRIORITY])
300 rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
301
302 if (tb[FRA_IIFNAME]) {
303 struct net_device *dev;
304
305 rule->iifindex = -1;
306 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
307 dev = __dev_get_by_name(net, rule->iifname);
308 if (dev)
309 rule->iifindex = dev->ifindex;
310 }
311
312 if (tb[FRA_OIFNAME]) {
313 struct net_device *dev;
314
315 rule->oifindex = -1;
316 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
317 dev = __dev_get_by_name(net, rule->oifname);
318 if (dev)
319 rule->oifindex = dev->ifindex;
320 }
321
322 if (tb[FRA_FWMARK]) {
323 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
324 if (rule->mark)
325 /* compatibility: if the mark value is non-zero all bits
326 * are compared unless a mask is explicitly specified.
327 */
328 rule->mark_mask = 0xFFFFFFFF;
329 }
330
331 if (tb[FRA_FWMASK])
332 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
333
334 rule->action = frh->action;
335 rule->flags = frh->flags;
336 rule->table = frh_get_table(frh, tb);
337
338 if (!tb[FRA_PRIORITY] && ops->default_pref)
339 rule->pref = ops->default_pref(ops);
340
341 err = -EINVAL;
342 if (tb[FRA_GOTO]) {
343 if (rule->action != FR_ACT_GOTO)
344 goto errout_free;
345
346 rule->target = nla_get_u32(tb[FRA_GOTO]);
347 /* Backward jumps are prohibited to avoid endless loops */
348 if (rule->target <= rule->pref)
349 goto errout_free;
350
351 list_for_each_entry(r, &ops->rules_list, list) {
352 if (r->pref == rule->target) {
353 RCU_INIT_POINTER(rule->ctarget, r);
354 break;
355 }
356 }
357
358 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
359 unresolved = 1;
360 } else if (rule->action == FR_ACT_GOTO)
361 goto errout_free;
362
363 err = ops->configure(rule, skb, frh, tb);
364 if (err < 0)
365 goto errout_free;
366
367 list_for_each_entry(r, &ops->rules_list, list) {
368 if (r->pref > rule->pref)
369 break;
370 last = r;
371 }
372
373 fib_rule_get(rule);
374
375 if (last)
376 list_add_rcu(&rule->list, &last->list);
377 else
378 list_add_rcu(&rule->list, &ops->rules_list);
379
380 if (ops->unresolved_rules) {
381 /*
382 * There are unresolved goto rules in the list, check if
383 * any of them are pointing to this new rule.
384 */
385 list_for_each_entry(r, &ops->rules_list, list) {
386 if (r->action == FR_ACT_GOTO &&
387 r->target == rule->pref &&
388 rtnl_dereference(r->ctarget) == NULL) {
389 rcu_assign_pointer(r->ctarget, rule);
390 if (--ops->unresolved_rules == 0)
391 break;
392 }
393 }
394 }
395
396 if (rule->action == FR_ACT_GOTO)
397 ops->nr_goto_rules++;
398
399 if (unresolved)
400 ops->unresolved_rules++;
401
402 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
403 flush_route_cache(ops);
404 rules_ops_put(ops);
405 return 0;
406
407errout_free:
408 release_net(rule->fr_net);
409 kfree(rule);
410errout:
411 rules_ops_put(ops);
412 return err;
413}
414
415static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
416{
417 struct net *net = sock_net(skb->sk);
418 struct fib_rule_hdr *frh = nlmsg_data(nlh);
419 struct fib_rules_ops *ops = NULL;
420 struct fib_rule *rule, *tmp;
421 struct nlattr *tb[FRA_MAX+1];
422 int err = -EINVAL;
423
424 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
425 goto errout;
426
427 ops = lookup_rules_ops(net, frh->family);
428 if (ops == NULL) {
429 err = -EAFNOSUPPORT;
430 goto errout;
431 }
432
433 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
434 if (err < 0)
435 goto errout;
436
437 err = validate_rulemsg(frh, tb, ops);
438 if (err < 0)
439 goto errout;
440
441 list_for_each_entry(rule, &ops->rules_list, list) {
442 if (frh->action && (frh->action != rule->action))
443 continue;
444
445 if (frh->table && (frh_get_table(frh, tb) != rule->table))
446 continue;
447
448 if (tb[FRA_PRIORITY] &&
449 (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
450 continue;
451
452 if (tb[FRA_IIFNAME] &&
453 nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
454 continue;
455
456 if (tb[FRA_OIFNAME] &&
457 nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
458 continue;
459
460 if (tb[FRA_FWMARK] &&
461 (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
462 continue;
463
464 if (tb[FRA_FWMASK] &&
465 (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
466 continue;
467
468 if (!ops->compare(rule, frh, tb))
469 continue;
470
471 if (rule->flags & FIB_RULE_PERMANENT) {
472 err = -EPERM;
473 goto errout;
474 }
475
476 list_del_rcu(&rule->list);
477
478 if (rule->action == FR_ACT_GOTO) {
479 ops->nr_goto_rules--;
480 if (rtnl_dereference(rule->ctarget) == NULL)
481 ops->unresolved_rules--;
482 }
483
484 /*
485 * Check if this rule is a target to any of them. If so,
486 * disable them. As this operation is eventually very
487 * expensive, it is only performed if goto rules have
488 * actually been added.
489 */
490 if (ops->nr_goto_rules > 0) {
491 list_for_each_entry(tmp, &ops->rules_list, list) {
492 if (rtnl_dereference(tmp->ctarget) == rule) {
493 rcu_assign_pointer(tmp->ctarget, NULL);
494 ops->unresolved_rules++;
495 }
496 }
497 }
498
499 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
500 NETLINK_CB(skb).pid);
501 fib_rule_put(rule);
502 flush_route_cache(ops);
503 rules_ops_put(ops);
504 return 0;
505 }
506
507 err = -ENOENT;
508errout:
509 rules_ops_put(ops);
510 return err;
511}
512
513static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
514 struct fib_rule *rule)
515{
516 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
517 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
518 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
519 + nla_total_size(4) /* FRA_PRIORITY */
520 + nla_total_size(4) /* FRA_TABLE */
521 + nla_total_size(4) /* FRA_FWMARK */
522 + nla_total_size(4); /* FRA_FWMASK */
523
524 if (ops->nlmsg_payload)
525 payload += ops->nlmsg_payload(rule);
526
527 return payload;
528}
529
530static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
531 u32 pid, u32 seq, int type, int flags,
532 struct fib_rules_ops *ops)
533{
534 struct nlmsghdr *nlh;
535 struct fib_rule_hdr *frh;
536
537 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
538 if (nlh == NULL)
539 return -EMSGSIZE;
540
541 frh = nlmsg_data(nlh);
542 frh->family = ops->family;
543 frh->table = rule->table;
544 NLA_PUT_U32(skb, FRA_TABLE, rule->table);
545 frh->res1 = 0;
546 frh->res2 = 0;
547 frh->action = rule->action;
548 frh->flags = rule->flags;
549
550 if (rule->action == FR_ACT_GOTO &&
551 rcu_dereference_raw(rule->ctarget) == NULL)
552 frh->flags |= FIB_RULE_UNRESOLVED;
553
554 if (rule->iifname[0]) {
555 NLA_PUT_STRING(skb, FRA_IIFNAME, rule->iifname);
556
557 if (rule->iifindex == -1)
558 frh->flags |= FIB_RULE_IIF_DETACHED;
559 }
560
561 if (rule->oifname[0]) {
562 NLA_PUT_STRING(skb, FRA_OIFNAME, rule->oifname);
563
564 if (rule->oifindex == -1)
565 frh->flags |= FIB_RULE_OIF_DETACHED;
566 }
567
568 if (rule->pref)
569 NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
570
571 if (rule->mark)
572 NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
573
574 if (rule->mark_mask || rule->mark)
575 NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
576
577 if (rule->target)
578 NLA_PUT_U32(skb, FRA_GOTO, rule->target);
579
580 if (ops->fill(rule, skb, frh) < 0)
581 goto nla_put_failure;
582
583 return nlmsg_end(skb, nlh);
584
585nla_put_failure:
586 nlmsg_cancel(skb, nlh);
587 return -EMSGSIZE;
588}
589
590static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
591 struct fib_rules_ops *ops)
592{
593 int idx = 0;
594 struct fib_rule *rule;
595
596 rcu_read_lock();
597 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
598 if (idx < cb->args[1])
599 goto skip;
600
601 if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
602 cb->nlh->nlmsg_seq, RTM_NEWRULE,
603 NLM_F_MULTI, ops) < 0)
604 break;
605skip:
606 idx++;
607 }
608 rcu_read_unlock();
609 cb->args[1] = idx;
610 rules_ops_put(ops);
611
612 return skb->len;
613}
614
615static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
616{
617 struct net *net = sock_net(skb->sk);
618 struct fib_rules_ops *ops;
619 int idx = 0, family;
620
621 family = rtnl_msg_family(cb->nlh);
622 if (family != AF_UNSPEC) {
623 /* Protocol specific dump request */
624 ops = lookup_rules_ops(net, family);
625 if (ops == NULL)
626 return -EAFNOSUPPORT;
627
628 return dump_rules(skb, cb, ops);
629 }
630
631 rcu_read_lock();
632 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
633 if (idx < cb->args[0] || !try_module_get(ops->owner))
634 goto skip;
635
636 if (dump_rules(skb, cb, ops) < 0)
637 break;
638
639 cb->args[1] = 0;
640skip:
641 idx++;
642 }
643 rcu_read_unlock();
644 cb->args[0] = idx;
645
646 return skb->len;
647}
648
649static void notify_rule_change(int event, struct fib_rule *rule,
650 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
651 u32 pid)
652{
653 struct net *net;
654 struct sk_buff *skb;
655 int err = -ENOBUFS;
656
657 net = ops->fro_net;
658 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
659 if (skb == NULL)
660 goto errout;
661
662 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
663 if (err < 0) {
664 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
665 WARN_ON(err == -EMSGSIZE);
666 kfree_skb(skb);
667 goto errout;
668 }
669
670 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
671 return;
672errout:
673 if (err < 0)
674 rtnl_set_sk_err(net, ops->nlgroup, err);
675}
676
677static void attach_rules(struct list_head *rules, struct net_device *dev)
678{
679 struct fib_rule *rule;
680
681 list_for_each_entry(rule, rules, list) {
682 if (rule->iifindex == -1 &&
683 strcmp(dev->name, rule->iifname) == 0)
684 rule->iifindex = dev->ifindex;
685 if (rule->oifindex == -1 &&
686 strcmp(dev->name, rule->oifname) == 0)
687 rule->oifindex = dev->ifindex;
688 }
689}
690
691static void detach_rules(struct list_head *rules, struct net_device *dev)
692{
693 struct fib_rule *rule;
694
695 list_for_each_entry(rule, rules, list) {
696 if (rule->iifindex == dev->ifindex)
697 rule->iifindex = -1;
698 if (rule->oifindex == dev->ifindex)
699 rule->oifindex = -1;
700 }
701}
702
703
704static int fib_rules_event(struct notifier_block *this, unsigned long event,
705 void *ptr)
706{
707 struct net_device *dev = ptr;
708 struct net *net = dev_net(dev);
709 struct fib_rules_ops *ops;
710
711 ASSERT_RTNL();
712
713 switch (event) {
714 case NETDEV_REGISTER:
715 list_for_each_entry(ops, &net->rules_ops, list)
716 attach_rules(&ops->rules_list, dev);
717 break;
718
719 case NETDEV_UNREGISTER:
720 list_for_each_entry(ops, &net->rules_ops, list)
721 detach_rules(&ops->rules_list, dev);
722 break;
723 }
724
725 return NOTIFY_DONE;
726}
727
728static struct notifier_block fib_rules_notifier = {
729 .notifier_call = fib_rules_event,
730};
731
732static int __net_init fib_rules_net_init(struct net *net)
733{
734 INIT_LIST_HEAD(&net->rules_ops);
735 spin_lock_init(&net->rules_mod_lock);
736 return 0;
737}
738
739static struct pernet_operations fib_rules_net_ops = {
740 .init = fib_rules_net_init,
741};
742
743static int __init fib_rules_init(void)
744{
745 int err;
746 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL);
747 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL);
748 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL);
749
750 err = register_pernet_subsys(&fib_rules_net_ops);
751 if (err < 0)
752 goto fail;
753
754 err = register_netdevice_notifier(&fib_rules_notifier);
755 if (err < 0)
756 goto fail_unregister;
757
758 return 0;
759
760fail_unregister:
761 unregister_pernet_subsys(&fib_rules_net_ops);
762fail:
763 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
764 rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
765 rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
766 return err;
767}
768
769subsys_initcall(fib_rules_init);