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netlink: pass extended ACK struct to parsing functions
[mirror_ubuntu-bionic-kernel.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 <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
21 static const struct fib_kuid_range fib_kuid_range_unset = {
22 KUIDT_INIT(0),
23 KUIDT_INIT(~0),
24 };
25
26 bool fib_rule_matchall(const struct fib_rule *rule)
27 {
28 if (rule->iifindex || rule->oifindex || rule->mark || rule->tun_id ||
29 rule->flags)
30 return false;
31 if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1)
32 return false;
33 if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) ||
34 !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end))
35 return false;
36 return true;
37 }
38 EXPORT_SYMBOL_GPL(fib_rule_matchall);
39
40 int fib_default_rule_add(struct fib_rules_ops *ops,
41 u32 pref, u32 table, u32 flags)
42 {
43 struct fib_rule *r;
44
45 r = kzalloc(ops->rule_size, GFP_KERNEL);
46 if (r == NULL)
47 return -ENOMEM;
48
49 atomic_set(&r->refcnt, 1);
50 r->action = FR_ACT_TO_TBL;
51 r->pref = pref;
52 r->table = table;
53 r->flags = flags;
54 r->fr_net = ops->fro_net;
55 r->uid_range = fib_kuid_range_unset;
56
57 r->suppress_prefixlen = -1;
58 r->suppress_ifgroup = -1;
59
60 /* The lock is not required here, the list in unreacheable
61 * at the moment this function is called */
62 list_add_tail(&r->list, &ops->rules_list);
63 return 0;
64 }
65 EXPORT_SYMBOL(fib_default_rule_add);
66
67 static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
68 {
69 struct list_head *pos;
70 struct fib_rule *rule;
71
72 if (!list_empty(&ops->rules_list)) {
73 pos = ops->rules_list.next;
74 if (pos->next != &ops->rules_list) {
75 rule = list_entry(pos->next, struct fib_rule, list);
76 if (rule->pref)
77 return rule->pref - 1;
78 }
79 }
80
81 return 0;
82 }
83
84 static void notify_rule_change(int event, struct fib_rule *rule,
85 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
86 u32 pid);
87
88 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
89 {
90 struct fib_rules_ops *ops;
91
92 rcu_read_lock();
93 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
94 if (ops->family == family) {
95 if (!try_module_get(ops->owner))
96 ops = NULL;
97 rcu_read_unlock();
98 return ops;
99 }
100 }
101 rcu_read_unlock();
102
103 return NULL;
104 }
105
106 static void rules_ops_put(struct fib_rules_ops *ops)
107 {
108 if (ops)
109 module_put(ops->owner);
110 }
111
112 static void flush_route_cache(struct fib_rules_ops *ops)
113 {
114 if (ops->flush_cache)
115 ops->flush_cache(ops);
116 }
117
118 static int __fib_rules_register(struct fib_rules_ops *ops)
119 {
120 int err = -EEXIST;
121 struct fib_rules_ops *o;
122 struct net *net;
123
124 net = ops->fro_net;
125
126 if (ops->rule_size < sizeof(struct fib_rule))
127 return -EINVAL;
128
129 if (ops->match == NULL || ops->configure == NULL ||
130 ops->compare == NULL || ops->fill == NULL ||
131 ops->action == NULL)
132 return -EINVAL;
133
134 spin_lock(&net->rules_mod_lock);
135 list_for_each_entry(o, &net->rules_ops, list)
136 if (ops->family == o->family)
137 goto errout;
138
139 list_add_tail_rcu(&ops->list, &net->rules_ops);
140 err = 0;
141 errout:
142 spin_unlock(&net->rules_mod_lock);
143
144 return err;
145 }
146
147 struct fib_rules_ops *
148 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
149 {
150 struct fib_rules_ops *ops;
151 int err;
152
153 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
154 if (ops == NULL)
155 return ERR_PTR(-ENOMEM);
156
157 INIT_LIST_HEAD(&ops->rules_list);
158 ops->fro_net = net;
159
160 err = __fib_rules_register(ops);
161 if (err) {
162 kfree(ops);
163 ops = ERR_PTR(err);
164 }
165
166 return ops;
167 }
168 EXPORT_SYMBOL_GPL(fib_rules_register);
169
170 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
171 {
172 struct fib_rule *rule, *tmp;
173
174 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
175 list_del_rcu(&rule->list);
176 if (ops->delete)
177 ops->delete(rule);
178 fib_rule_put(rule);
179 }
180 }
181
182 void fib_rules_unregister(struct fib_rules_ops *ops)
183 {
184 struct net *net = ops->fro_net;
185
186 spin_lock(&net->rules_mod_lock);
187 list_del_rcu(&ops->list);
188 spin_unlock(&net->rules_mod_lock);
189
190 fib_rules_cleanup_ops(ops);
191 kfree_rcu(ops, rcu);
192 }
193 EXPORT_SYMBOL_GPL(fib_rules_unregister);
194
195 static int uid_range_set(struct fib_kuid_range *range)
196 {
197 return uid_valid(range->start) && uid_valid(range->end);
198 }
199
200 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
201 {
202 struct fib_rule_uid_range *in;
203 struct fib_kuid_range out;
204
205 in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]);
206
207 out.start = make_kuid(current_user_ns(), in->start);
208 out.end = make_kuid(current_user_ns(), in->end);
209
210 return out;
211 }
212
213 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
214 {
215 struct fib_rule_uid_range out = {
216 from_kuid_munged(current_user_ns(), range->start),
217 from_kuid_munged(current_user_ns(), range->end)
218 };
219
220 return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out);
221 }
222
223 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
224 struct flowi *fl, int flags,
225 struct fib_lookup_arg *arg)
226 {
227 int ret = 0;
228
229 if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
230 goto out;
231
232 if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
233 goto out;
234
235 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
236 goto out;
237
238 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
239 goto out;
240
241 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
242 goto out;
243
244 if (uid_lt(fl->flowi_uid, rule->uid_range.start) ||
245 uid_gt(fl->flowi_uid, rule->uid_range.end))
246 goto out;
247
248 ret = ops->match(rule, fl, flags);
249 out:
250 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
251 }
252
253 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
254 int flags, struct fib_lookup_arg *arg)
255 {
256 struct fib_rule *rule;
257 int err;
258
259 rcu_read_lock();
260
261 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
262 jumped:
263 if (!fib_rule_match(rule, ops, fl, flags, arg))
264 continue;
265
266 if (rule->action == FR_ACT_GOTO) {
267 struct fib_rule *target;
268
269 target = rcu_dereference(rule->ctarget);
270 if (target == NULL) {
271 continue;
272 } else {
273 rule = target;
274 goto jumped;
275 }
276 } else if (rule->action == FR_ACT_NOP)
277 continue;
278 else
279 err = ops->action(rule, fl, flags, arg);
280
281 if (!err && ops->suppress && ops->suppress(rule, arg))
282 continue;
283
284 if (err != -EAGAIN) {
285 if ((arg->flags & FIB_LOOKUP_NOREF) ||
286 likely(atomic_inc_not_zero(&rule->refcnt))) {
287 arg->rule = rule;
288 goto out;
289 }
290 break;
291 }
292 }
293
294 err = -ESRCH;
295 out:
296 rcu_read_unlock();
297
298 return err;
299 }
300 EXPORT_SYMBOL_GPL(fib_rules_lookup);
301
302 static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
303 struct fib_rules_ops *ops)
304 {
305 int err = -EINVAL;
306
307 if (frh->src_len)
308 if (tb[FRA_SRC] == NULL ||
309 frh->src_len > (ops->addr_size * 8) ||
310 nla_len(tb[FRA_SRC]) != ops->addr_size)
311 goto errout;
312
313 if (frh->dst_len)
314 if (tb[FRA_DST] == NULL ||
315 frh->dst_len > (ops->addr_size * 8) ||
316 nla_len(tb[FRA_DST]) != ops->addr_size)
317 goto errout;
318
319 err = 0;
320 errout:
321 return err;
322 }
323
324 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
325 struct nlattr **tb, struct fib_rule *rule)
326 {
327 struct fib_rule *r;
328
329 list_for_each_entry(r, &ops->rules_list, list) {
330 if (r->action != rule->action)
331 continue;
332
333 if (r->table != rule->table)
334 continue;
335
336 if (r->pref != rule->pref)
337 continue;
338
339 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
340 continue;
341
342 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
343 continue;
344
345 if (r->mark != rule->mark)
346 continue;
347
348 if (r->mark_mask != rule->mark_mask)
349 continue;
350
351 if (r->tun_id != rule->tun_id)
352 continue;
353
354 if (r->fr_net != rule->fr_net)
355 continue;
356
357 if (r->l3mdev != rule->l3mdev)
358 continue;
359
360 if (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
361 !uid_eq(r->uid_range.end, rule->uid_range.end))
362 continue;
363
364 if (!ops->compare(r, frh, tb))
365 continue;
366 return 1;
367 }
368 return 0;
369 }
370
371 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh)
372 {
373 struct net *net = sock_net(skb->sk);
374 struct fib_rule_hdr *frh = nlmsg_data(nlh);
375 struct fib_rules_ops *ops = NULL;
376 struct fib_rule *rule, *r, *last = NULL;
377 struct nlattr *tb[FRA_MAX+1];
378 int err = -EINVAL, unresolved = 0;
379
380 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
381 goto errout;
382
383 ops = lookup_rules_ops(net, frh->family);
384 if (ops == NULL) {
385 err = -EAFNOSUPPORT;
386 goto errout;
387 }
388
389 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy, NULL);
390 if (err < 0)
391 goto errout;
392
393 err = validate_rulemsg(frh, tb, ops);
394 if (err < 0)
395 goto errout;
396
397 rule = kzalloc(ops->rule_size, GFP_KERNEL);
398 if (rule == NULL) {
399 err = -ENOMEM;
400 goto errout;
401 }
402 rule->fr_net = net;
403
404 rule->pref = tb[FRA_PRIORITY] ? nla_get_u32(tb[FRA_PRIORITY])
405 : fib_default_rule_pref(ops);
406
407 if (tb[FRA_IIFNAME]) {
408 struct net_device *dev;
409
410 rule->iifindex = -1;
411 nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
412 dev = __dev_get_by_name(net, rule->iifname);
413 if (dev)
414 rule->iifindex = dev->ifindex;
415 }
416
417 if (tb[FRA_OIFNAME]) {
418 struct net_device *dev;
419
420 rule->oifindex = -1;
421 nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
422 dev = __dev_get_by_name(net, rule->oifname);
423 if (dev)
424 rule->oifindex = dev->ifindex;
425 }
426
427 if (tb[FRA_FWMARK]) {
428 rule->mark = nla_get_u32(tb[FRA_FWMARK]);
429 if (rule->mark)
430 /* compatibility: if the mark value is non-zero all bits
431 * are compared unless a mask is explicitly specified.
432 */
433 rule->mark_mask = 0xFFFFFFFF;
434 }
435
436 if (tb[FRA_FWMASK])
437 rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
438
439 if (tb[FRA_TUN_ID])
440 rule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
441
442 if (tb[FRA_L3MDEV]) {
443 #ifdef CONFIG_NET_L3_MASTER_DEV
444 rule->l3mdev = nla_get_u8(tb[FRA_L3MDEV]);
445 if (rule->l3mdev != 1)
446 #endif
447 goto errout_free;
448 }
449
450 rule->action = frh->action;
451 rule->flags = frh->flags;
452 rule->table = frh_get_table(frh, tb);
453 if (tb[FRA_SUPPRESS_PREFIXLEN])
454 rule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
455 else
456 rule->suppress_prefixlen = -1;
457
458 if (tb[FRA_SUPPRESS_IFGROUP])
459 rule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
460 else
461 rule->suppress_ifgroup = -1;
462
463 err = -EINVAL;
464 if (tb[FRA_GOTO]) {
465 if (rule->action != FR_ACT_GOTO)
466 goto errout_free;
467
468 rule->target = nla_get_u32(tb[FRA_GOTO]);
469 /* Backward jumps are prohibited to avoid endless loops */
470 if (rule->target <= rule->pref)
471 goto errout_free;
472
473 list_for_each_entry(r, &ops->rules_list, list) {
474 if (r->pref == rule->target) {
475 RCU_INIT_POINTER(rule->ctarget, r);
476 break;
477 }
478 }
479
480 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
481 unresolved = 1;
482 } else if (rule->action == FR_ACT_GOTO)
483 goto errout_free;
484
485 if (rule->l3mdev && rule->table)
486 goto errout_free;
487
488 if (tb[FRA_UID_RANGE]) {
489 if (current_user_ns() != net->user_ns) {
490 err = -EPERM;
491 goto errout_free;
492 }
493
494 rule->uid_range = nla_get_kuid_range(tb);
495
496 if (!uid_range_set(&rule->uid_range) ||
497 !uid_lte(rule->uid_range.start, rule->uid_range.end))
498 goto errout_free;
499 } else {
500 rule->uid_range = fib_kuid_range_unset;
501 }
502
503 if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
504 rule_exists(ops, frh, tb, rule)) {
505 err = -EEXIST;
506 goto errout_free;
507 }
508
509 err = ops->configure(rule, skb, frh, tb);
510 if (err < 0)
511 goto errout_free;
512
513 list_for_each_entry(r, &ops->rules_list, list) {
514 if (r->pref > rule->pref)
515 break;
516 last = r;
517 }
518
519 fib_rule_get(rule);
520
521 if (last)
522 list_add_rcu(&rule->list, &last->list);
523 else
524 list_add_rcu(&rule->list, &ops->rules_list);
525
526 if (ops->unresolved_rules) {
527 /*
528 * There are unresolved goto rules in the list, check if
529 * any of them are pointing to this new rule.
530 */
531 list_for_each_entry(r, &ops->rules_list, list) {
532 if (r->action == FR_ACT_GOTO &&
533 r->target == rule->pref &&
534 rtnl_dereference(r->ctarget) == NULL) {
535 rcu_assign_pointer(r->ctarget, rule);
536 if (--ops->unresolved_rules == 0)
537 break;
538 }
539 }
540 }
541
542 if (rule->action == FR_ACT_GOTO)
543 ops->nr_goto_rules++;
544
545 if (unresolved)
546 ops->unresolved_rules++;
547
548 if (rule->tun_id)
549 ip_tunnel_need_metadata();
550
551 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
552 flush_route_cache(ops);
553 rules_ops_put(ops);
554 return 0;
555
556 errout_free:
557 kfree(rule);
558 errout:
559 rules_ops_put(ops);
560 return err;
561 }
562 EXPORT_SYMBOL_GPL(fib_nl_newrule);
563
564 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh)
565 {
566 struct net *net = sock_net(skb->sk);
567 struct fib_rule_hdr *frh = nlmsg_data(nlh);
568 struct fib_rules_ops *ops = NULL;
569 struct fib_rule *rule, *tmp;
570 struct nlattr *tb[FRA_MAX+1];
571 struct fib_kuid_range range;
572 int err = -EINVAL;
573
574 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
575 goto errout;
576
577 ops = lookup_rules_ops(net, frh->family);
578 if (ops == NULL) {
579 err = -EAFNOSUPPORT;
580 goto errout;
581 }
582
583 err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy, NULL);
584 if (err < 0)
585 goto errout;
586
587 err = validate_rulemsg(frh, tb, ops);
588 if (err < 0)
589 goto errout;
590
591 if (tb[FRA_UID_RANGE]) {
592 range = nla_get_kuid_range(tb);
593 if (!uid_range_set(&range))
594 goto errout;
595 } else {
596 range = fib_kuid_range_unset;
597 }
598
599 list_for_each_entry(rule, &ops->rules_list, list) {
600 if (frh->action && (frh->action != rule->action))
601 continue;
602
603 if (frh_get_table(frh, tb) &&
604 (frh_get_table(frh, tb) != rule->table))
605 continue;
606
607 if (tb[FRA_PRIORITY] &&
608 (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
609 continue;
610
611 if (tb[FRA_IIFNAME] &&
612 nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
613 continue;
614
615 if (tb[FRA_OIFNAME] &&
616 nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
617 continue;
618
619 if (tb[FRA_FWMARK] &&
620 (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
621 continue;
622
623 if (tb[FRA_FWMASK] &&
624 (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
625 continue;
626
627 if (tb[FRA_TUN_ID] &&
628 (rule->tun_id != nla_get_be64(tb[FRA_TUN_ID])))
629 continue;
630
631 if (tb[FRA_L3MDEV] &&
632 (rule->l3mdev != nla_get_u8(tb[FRA_L3MDEV])))
633 continue;
634
635 if (uid_range_set(&range) &&
636 (!uid_eq(rule->uid_range.start, range.start) ||
637 !uid_eq(rule->uid_range.end, range.end)))
638 continue;
639
640 if (!ops->compare(rule, frh, tb))
641 continue;
642
643 if (rule->flags & FIB_RULE_PERMANENT) {
644 err = -EPERM;
645 goto errout;
646 }
647
648 if (ops->delete) {
649 err = ops->delete(rule);
650 if (err)
651 goto errout;
652 }
653
654 if (rule->tun_id)
655 ip_tunnel_unneed_metadata();
656
657 list_del_rcu(&rule->list);
658
659 if (rule->action == FR_ACT_GOTO) {
660 ops->nr_goto_rules--;
661 if (rtnl_dereference(rule->ctarget) == NULL)
662 ops->unresolved_rules--;
663 }
664
665 /*
666 * Check if this rule is a target to any of them. If so,
667 * disable them. As this operation is eventually very
668 * expensive, it is only performed if goto rules have
669 * actually been added.
670 */
671 if (ops->nr_goto_rules > 0) {
672 list_for_each_entry(tmp, &ops->rules_list, list) {
673 if (rtnl_dereference(tmp->ctarget) == rule) {
674 RCU_INIT_POINTER(tmp->ctarget, NULL);
675 ops->unresolved_rules++;
676 }
677 }
678 }
679
680 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
681 NETLINK_CB(skb).portid);
682 fib_rule_put(rule);
683 flush_route_cache(ops);
684 rules_ops_put(ops);
685 return 0;
686 }
687
688 err = -ENOENT;
689 errout:
690 rules_ops_put(ops);
691 return err;
692 }
693 EXPORT_SYMBOL_GPL(fib_nl_delrule);
694
695 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
696 struct fib_rule *rule)
697 {
698 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
699 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
700 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
701 + nla_total_size(4) /* FRA_PRIORITY */
702 + nla_total_size(4) /* FRA_TABLE */
703 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
704 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
705 + nla_total_size(4) /* FRA_FWMARK */
706 + nla_total_size(4) /* FRA_FWMASK */
707 + nla_total_size_64bit(8) /* FRA_TUN_ID */
708 + nla_total_size(sizeof(struct fib_kuid_range));
709
710 if (ops->nlmsg_payload)
711 payload += ops->nlmsg_payload(rule);
712
713 return payload;
714 }
715
716 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
717 u32 pid, u32 seq, int type, int flags,
718 struct fib_rules_ops *ops)
719 {
720 struct nlmsghdr *nlh;
721 struct fib_rule_hdr *frh;
722
723 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
724 if (nlh == NULL)
725 return -EMSGSIZE;
726
727 frh = nlmsg_data(nlh);
728 frh->family = ops->family;
729 frh->table = rule->table;
730 if (nla_put_u32(skb, FRA_TABLE, rule->table))
731 goto nla_put_failure;
732 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
733 goto nla_put_failure;
734 frh->res1 = 0;
735 frh->res2 = 0;
736 frh->action = rule->action;
737 frh->flags = rule->flags;
738
739 if (rule->action == FR_ACT_GOTO &&
740 rcu_access_pointer(rule->ctarget) == NULL)
741 frh->flags |= FIB_RULE_UNRESOLVED;
742
743 if (rule->iifname[0]) {
744 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
745 goto nla_put_failure;
746 if (rule->iifindex == -1)
747 frh->flags |= FIB_RULE_IIF_DETACHED;
748 }
749
750 if (rule->oifname[0]) {
751 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
752 goto nla_put_failure;
753 if (rule->oifindex == -1)
754 frh->flags |= FIB_RULE_OIF_DETACHED;
755 }
756
757 if ((rule->pref &&
758 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
759 (rule->mark &&
760 nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
761 ((rule->mark_mask || rule->mark) &&
762 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
763 (rule->target &&
764 nla_put_u32(skb, FRA_GOTO, rule->target)) ||
765 (rule->tun_id &&
766 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
767 (rule->l3mdev &&
768 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
769 (uid_range_set(&rule->uid_range) &&
770 nla_put_uid_range(skb, &rule->uid_range)))
771 goto nla_put_failure;
772
773 if (rule->suppress_ifgroup != -1) {
774 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
775 goto nla_put_failure;
776 }
777
778 if (ops->fill(rule, skb, frh) < 0)
779 goto nla_put_failure;
780
781 nlmsg_end(skb, nlh);
782 return 0;
783
784 nla_put_failure:
785 nlmsg_cancel(skb, nlh);
786 return -EMSGSIZE;
787 }
788
789 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
790 struct fib_rules_ops *ops)
791 {
792 int idx = 0;
793 struct fib_rule *rule;
794 int err = 0;
795
796 rcu_read_lock();
797 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
798 if (idx < cb->args[1])
799 goto skip;
800
801 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
802 cb->nlh->nlmsg_seq, RTM_NEWRULE,
803 NLM_F_MULTI, ops);
804 if (err)
805 break;
806 skip:
807 idx++;
808 }
809 rcu_read_unlock();
810 cb->args[1] = idx;
811 rules_ops_put(ops);
812
813 return err;
814 }
815
816 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
817 {
818 struct net *net = sock_net(skb->sk);
819 struct fib_rules_ops *ops;
820 int idx = 0, family;
821
822 family = rtnl_msg_family(cb->nlh);
823 if (family != AF_UNSPEC) {
824 /* Protocol specific dump request */
825 ops = lookup_rules_ops(net, family);
826 if (ops == NULL)
827 return -EAFNOSUPPORT;
828
829 dump_rules(skb, cb, ops);
830
831 return skb->len;
832 }
833
834 rcu_read_lock();
835 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
836 if (idx < cb->args[0] || !try_module_get(ops->owner))
837 goto skip;
838
839 if (dump_rules(skb, cb, ops) < 0)
840 break;
841
842 cb->args[1] = 0;
843 skip:
844 idx++;
845 }
846 rcu_read_unlock();
847 cb->args[0] = idx;
848
849 return skb->len;
850 }
851
852 static void notify_rule_change(int event, struct fib_rule *rule,
853 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
854 u32 pid)
855 {
856 struct net *net;
857 struct sk_buff *skb;
858 int err = -ENOBUFS;
859
860 net = ops->fro_net;
861 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
862 if (skb == NULL)
863 goto errout;
864
865 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
866 if (err < 0) {
867 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
868 WARN_ON(err == -EMSGSIZE);
869 kfree_skb(skb);
870 goto errout;
871 }
872
873 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
874 return;
875 errout:
876 if (err < 0)
877 rtnl_set_sk_err(net, ops->nlgroup, err);
878 }
879
880 static void attach_rules(struct list_head *rules, struct net_device *dev)
881 {
882 struct fib_rule *rule;
883
884 list_for_each_entry(rule, rules, list) {
885 if (rule->iifindex == -1 &&
886 strcmp(dev->name, rule->iifname) == 0)
887 rule->iifindex = dev->ifindex;
888 if (rule->oifindex == -1 &&
889 strcmp(dev->name, rule->oifname) == 0)
890 rule->oifindex = dev->ifindex;
891 }
892 }
893
894 static void detach_rules(struct list_head *rules, struct net_device *dev)
895 {
896 struct fib_rule *rule;
897
898 list_for_each_entry(rule, rules, list) {
899 if (rule->iifindex == dev->ifindex)
900 rule->iifindex = -1;
901 if (rule->oifindex == dev->ifindex)
902 rule->oifindex = -1;
903 }
904 }
905
906
907 static int fib_rules_event(struct notifier_block *this, unsigned long event,
908 void *ptr)
909 {
910 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
911 struct net *net = dev_net(dev);
912 struct fib_rules_ops *ops;
913
914 ASSERT_RTNL();
915
916 switch (event) {
917 case NETDEV_REGISTER:
918 list_for_each_entry(ops, &net->rules_ops, list)
919 attach_rules(&ops->rules_list, dev);
920 break;
921
922 case NETDEV_CHANGENAME:
923 list_for_each_entry(ops, &net->rules_ops, list) {
924 detach_rules(&ops->rules_list, dev);
925 attach_rules(&ops->rules_list, dev);
926 }
927 break;
928
929 case NETDEV_UNREGISTER:
930 list_for_each_entry(ops, &net->rules_ops, list)
931 detach_rules(&ops->rules_list, dev);
932 break;
933 }
934
935 return NOTIFY_DONE;
936 }
937
938 static struct notifier_block fib_rules_notifier = {
939 .notifier_call = fib_rules_event,
940 };
941
942 static int __net_init fib_rules_net_init(struct net *net)
943 {
944 INIT_LIST_HEAD(&net->rules_ops);
945 spin_lock_init(&net->rules_mod_lock);
946 return 0;
947 }
948
949 static struct pernet_operations fib_rules_net_ops = {
950 .init = fib_rules_net_init,
951 };
952
953 static int __init fib_rules_init(void)
954 {
955 int err;
956 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL);
957 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL);
958 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL);
959
960 err = register_pernet_subsys(&fib_rules_net_ops);
961 if (err < 0)
962 goto fail;
963
964 err = register_netdevice_notifier(&fib_rules_notifier);
965 if (err < 0)
966 goto fail_unregister;
967
968 return 0;
969
970 fail_unregister:
971 unregister_pernet_subsys(&fib_rules_net_ops);
972 fail:
973 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
974 rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
975 rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
976 return err;
977 }
978
979 subsys_initcall(fib_rules_init);
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