1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * net/core/fib_rules.c Generic Routing Rules
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 */
7
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/list.h>
12 #include <linux/module.h>
13 #include <net/net_namespace.h>
14 #include <net/inet_dscp.h>
15 #include <net/sock.h>
16 #include <net/fib_rules.h>
17 #include <net/ip_tunnels.h>
18 #include <linux/indirect_call_wrapper.h>
19
20 #if defined(CONFIG_IPV6) && defined(CONFIG_IPV6_MULTIPLE_TABLES)
21 #ifdef CONFIG_IP_MULTIPLE_TABLES
22 #define INDIRECT_CALL_MT(f, f2, f1, ...) \
23 INDIRECT_CALL_INET(f, f2, f1, __VA_ARGS__)
24 #else
25 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
26 #endif
27 #elif defined(CONFIG_IP_MULTIPLE_TABLES)
28 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__)
29 #else
30 #define INDIRECT_CALL_MT(f, f2, f1, ...) f(__VA_ARGS__)
31 #endif
32
33 static const struct fib_kuid_range fib_kuid_range_unset = {
34 KUIDT_INIT(0),
35 KUIDT_INIT(~0),
36 };
37
fib_rule_matchall(const struct fib_rule * rule)38 bool fib_rule_matchall(const struct fib_rule *rule)
39 {
40 if (READ_ONCE(rule->iifindex) || READ_ONCE(rule->oifindex) ||
41 rule->mark || rule->tun_id || rule->flags)
42 return false;
43 if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1)
44 return false;
45 if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) ||
46 !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end))
47 return false;
48 if (fib_rule_port_range_set(&rule->sport_range))
49 return false;
50 if (fib_rule_port_range_set(&rule->dport_range))
51 return false;
52 return true;
53 }
54 EXPORT_SYMBOL_GPL(fib_rule_matchall);
55
fib_default_rule_add(struct fib_rules_ops * ops,u32 pref,u32 table)56 int fib_default_rule_add(struct fib_rules_ops *ops,
57 u32 pref, u32 table)
58 {
59 struct fib_rule *r;
60
61 r = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
62 if (r == NULL)
63 return -ENOMEM;
64
65 refcount_set(&r->refcnt, 1);
66 r->action = FR_ACT_TO_TBL;
67 r->pref = pref;
68 r->table = table;
69 r->proto = RTPROT_KERNEL;
70 r->fr_net = ops->fro_net;
71 r->uid_range = fib_kuid_range_unset;
72
73 r->suppress_prefixlen = -1;
74 r->suppress_ifgroup = -1;
75
76 /* The lock is not required here, the list in unreachable
77 * at the moment this function is called */
78 list_add_tail(&r->list, &ops->rules_list);
79 return 0;
80 }
81 EXPORT_SYMBOL(fib_default_rule_add);
82
fib_default_rule_pref(struct fib_rules_ops * ops)83 static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
84 {
85 struct list_head *pos;
86 struct fib_rule *rule;
87
88 if (!list_empty(&ops->rules_list)) {
89 pos = ops->rules_list.next;
90 if (pos->next != &ops->rules_list) {
91 rule = list_entry(pos->next, struct fib_rule, list);
92 if (rule->pref)
93 return rule->pref - 1;
94 }
95 }
96
97 return 0;
98 }
99
100 static void notify_rule_change(int event, struct fib_rule *rule,
101 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
102 u32 pid);
103
lookup_rules_ops(struct net * net,int family)104 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
105 {
106 struct fib_rules_ops *ops;
107
108 rcu_read_lock();
109 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
110 if (ops->family == family) {
111 if (!try_module_get(ops->owner))
112 ops = NULL;
113 rcu_read_unlock();
114 return ops;
115 }
116 }
117 rcu_read_unlock();
118
119 return NULL;
120 }
121
rules_ops_put(struct fib_rules_ops * ops)122 static void rules_ops_put(struct fib_rules_ops *ops)
123 {
124 if (ops)
125 module_put(ops->owner);
126 }
127
flush_route_cache(struct fib_rules_ops * ops)128 static void flush_route_cache(struct fib_rules_ops *ops)
129 {
130 if (ops->flush_cache)
131 ops->flush_cache(ops);
132 }
133
__fib_rules_register(struct fib_rules_ops * ops)134 static int __fib_rules_register(struct fib_rules_ops *ops)
135 {
136 int err = -EEXIST;
137 struct fib_rules_ops *o;
138 struct net *net;
139
140 net = ops->fro_net;
141
142 if (ops->rule_size < sizeof(struct fib_rule))
143 return -EINVAL;
144
145 if (ops->match == NULL || ops->configure == NULL ||
146 ops->compare == NULL || ops->fill == NULL ||
147 ops->action == NULL)
148 return -EINVAL;
149
150 spin_lock(&net->rules_mod_lock);
151 list_for_each_entry(o, &net->rules_ops, list)
152 if (ops->family == o->family)
153 goto errout;
154
155 list_add_tail_rcu(&ops->list, &net->rules_ops);
156 err = 0;
157 errout:
158 spin_unlock(&net->rules_mod_lock);
159
160 return err;
161 }
162
163 struct fib_rules_ops *
fib_rules_register(const struct fib_rules_ops * tmpl,struct net * net)164 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
165 {
166 struct fib_rules_ops *ops;
167 int err;
168
169 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
170 if (ops == NULL)
171 return ERR_PTR(-ENOMEM);
172
173 INIT_LIST_HEAD(&ops->rules_list);
174 ops->fro_net = net;
175
176 err = __fib_rules_register(ops);
177 if (err) {
178 kfree(ops);
179 ops = ERR_PTR(err);
180 }
181
182 return ops;
183 }
184 EXPORT_SYMBOL_GPL(fib_rules_register);
185
fib_rules_cleanup_ops(struct fib_rules_ops * ops)186 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
187 {
188 struct fib_rule *rule, *tmp;
189
190 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
191 list_del_rcu(&rule->list);
192 if (ops->delete)
193 ops->delete(rule);
194 fib_rule_put(rule);
195 }
196 }
197
fib_rules_unregister(struct fib_rules_ops * ops)198 void fib_rules_unregister(struct fib_rules_ops *ops)
199 {
200 struct net *net = ops->fro_net;
201
202 spin_lock(&net->rules_mod_lock);
203 list_del_rcu(&ops->list);
204 spin_unlock(&net->rules_mod_lock);
205
206 fib_rules_cleanup_ops(ops);
207 kfree_rcu(ops, rcu);
208 }
209 EXPORT_SYMBOL_GPL(fib_rules_unregister);
210
uid_range_set(struct fib_kuid_range * range)211 static int uid_range_set(struct fib_kuid_range *range)
212 {
213 return uid_valid(range->start) && uid_valid(range->end);
214 }
215
nla_get_kuid_range(struct nlattr ** tb)216 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
217 {
218 struct fib_rule_uid_range *in;
219 struct fib_kuid_range out;
220
221 in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]);
222
223 out.start = make_kuid(current_user_ns(), in->start);
224 out.end = make_kuid(current_user_ns(), in->end);
225
226 return out;
227 }
228
nla_put_uid_range(struct sk_buff * skb,struct fib_kuid_range * range)229 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
230 {
231 struct fib_rule_uid_range out = {
232 from_kuid_munged(current_user_ns(), range->start),
233 from_kuid_munged(current_user_ns(), range->end)
234 };
235
236 return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out);
237 }
238
nla_get_port_range(struct nlattr * pattr,struct fib_rule_port_range * port_range)239 static int nla_get_port_range(struct nlattr *pattr,
240 struct fib_rule_port_range *port_range)
241 {
242 const struct fib_rule_port_range *pr = nla_data(pattr);
243
244 if (!fib_rule_port_range_valid(pr))
245 return -EINVAL;
246
247 port_range->start = pr->start;
248 port_range->end = pr->end;
249
250 return 0;
251 }
252
nla_put_port_range(struct sk_buff * skb,int attrtype,struct fib_rule_port_range * range)253 static int nla_put_port_range(struct sk_buff *skb, int attrtype,
254 struct fib_rule_port_range *range)
255 {
256 return nla_put(skb, attrtype, sizeof(*range), range);
257 }
258
fib_rule_match(struct fib_rule * rule,struct fib_rules_ops * ops,struct flowi * fl,int flags,struct fib_lookup_arg * arg)259 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
260 struct flowi *fl, int flags,
261 struct fib_lookup_arg *arg)
262 {
263 int iifindex, oifindex, ret = 0;
264
265 iifindex = READ_ONCE(rule->iifindex);
266 if (iifindex && (iifindex != fl->flowi_iif))
267 goto out;
268
269 oifindex = READ_ONCE(rule->oifindex);
270 if (oifindex && (oifindex != fl->flowi_oif))
271 goto out;
272
273 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
274 goto out;
275
276 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
277 goto out;
278
279 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
280 goto out;
281
282 if (uid_lt(fl->flowi_uid, rule->uid_range.start) ||
283 uid_gt(fl->flowi_uid, rule->uid_range.end))
284 goto out;
285
286 ret = INDIRECT_CALL_MT(ops->match,
287 fib6_rule_match,
288 fib4_rule_match,
289 rule, fl, flags);
290 out:
291 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
292 }
293
fib_rules_lookup(struct fib_rules_ops * ops,struct flowi * fl,int flags,struct fib_lookup_arg * arg)294 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
295 int flags, struct fib_lookup_arg *arg)
296 {
297 struct fib_rule *rule;
298 int err;
299
300 rcu_read_lock();
301
302 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
303 jumped:
304 if (!fib_rule_match(rule, ops, fl, flags, arg))
305 continue;
306
307 if (rule->action == FR_ACT_GOTO) {
308 struct fib_rule *target;
309
310 target = rcu_dereference(rule->ctarget);
311 if (target == NULL) {
312 continue;
313 } else {
314 rule = target;
315 goto jumped;
316 }
317 } else if (rule->action == FR_ACT_NOP)
318 continue;
319 else
320 err = INDIRECT_CALL_MT(ops->action,
321 fib6_rule_action,
322 fib4_rule_action,
323 rule, fl, flags, arg);
324
325 if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress,
326 fib6_rule_suppress,
327 fib4_rule_suppress,
328 rule, flags, arg))
329 continue;
330
331 if (err != -EAGAIN) {
332 if ((arg->flags & FIB_LOOKUP_NOREF) ||
333 likely(refcount_inc_not_zero(&rule->refcnt))) {
334 arg->rule = rule;
335 goto out;
336 }
337 break;
338 }
339 }
340
341 err = -ESRCH;
342 out:
343 rcu_read_unlock();
344
345 return err;
346 }
347 EXPORT_SYMBOL_GPL(fib_rules_lookup);
348
call_fib_rule_notifier(struct notifier_block * nb,enum fib_event_type event_type,struct fib_rule * rule,int family,struct netlink_ext_ack * extack)349 static int call_fib_rule_notifier(struct notifier_block *nb,
350 enum fib_event_type event_type,
351 struct fib_rule *rule, int family,
352 struct netlink_ext_ack *extack)
353 {
354 struct fib_rule_notifier_info info = {
355 .info.family = family,
356 .info.extack = extack,
357 .rule = rule,
358 };
359
360 return call_fib_notifier(nb, event_type, &info.info);
361 }
362
call_fib_rule_notifiers(struct net * net,enum fib_event_type event_type,struct fib_rule * rule,struct fib_rules_ops * ops,struct netlink_ext_ack * extack)363 static int call_fib_rule_notifiers(struct net *net,
364 enum fib_event_type event_type,
365 struct fib_rule *rule,
366 struct fib_rules_ops *ops,
367 struct netlink_ext_ack *extack)
368 {
369 struct fib_rule_notifier_info info = {
370 .info.family = ops->family,
371 .info.extack = extack,
372 .rule = rule,
373 };
374
375 ops->fib_rules_seq++;
376 return call_fib_notifiers(net, event_type, &info.info);
377 }
378
379 /* Called with rcu_read_lock() */
fib_rules_dump(struct net * net,struct notifier_block * nb,int family,struct netlink_ext_ack * extack)380 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
381 struct netlink_ext_ack *extack)
382 {
383 struct fib_rules_ops *ops;
384 struct fib_rule *rule;
385 int err = 0;
386
387 ops = lookup_rules_ops(net, family);
388 if (!ops)
389 return -EAFNOSUPPORT;
390 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
391 err = call_fib_rule_notifier(nb, FIB_EVENT_RULE_ADD,
392 rule, family, extack);
393 if (err)
394 break;
395 }
396 rules_ops_put(ops);
397
398 return err;
399 }
400 EXPORT_SYMBOL_GPL(fib_rules_dump);
401
fib_rules_seq_read(struct net * net,int family)402 unsigned int fib_rules_seq_read(struct net *net, int family)
403 {
404 unsigned int fib_rules_seq;
405 struct fib_rules_ops *ops;
406
407 ASSERT_RTNL();
408
409 ops = lookup_rules_ops(net, family);
410 if (!ops)
411 return 0;
412 fib_rules_seq = ops->fib_rules_seq;
413 rules_ops_put(ops);
414
415 return fib_rules_seq;
416 }
417 EXPORT_SYMBOL_GPL(fib_rules_seq_read);
418
rule_find(struct fib_rules_ops * ops,struct fib_rule_hdr * frh,struct nlattr ** tb,struct fib_rule * rule,bool user_priority)419 static struct fib_rule *rule_find(struct fib_rules_ops *ops,
420 struct fib_rule_hdr *frh,
421 struct nlattr **tb,
422 struct fib_rule *rule,
423 bool user_priority)
424 {
425 struct fib_rule *r;
426
427 list_for_each_entry(r, &ops->rules_list, list) {
428 if (rule->action && r->action != rule->action)
429 continue;
430
431 if (rule->table && r->table != rule->table)
432 continue;
433
434 if (user_priority && r->pref != rule->pref)
435 continue;
436
437 if (rule->iifname[0] &&
438 memcmp(r->iifname, rule->iifname, IFNAMSIZ))
439 continue;
440
441 if (rule->oifname[0] &&
442 memcmp(r->oifname, rule->oifname, IFNAMSIZ))
443 continue;
444
445 if (rule->mark && r->mark != rule->mark)
446 continue;
447
448 if (rule->suppress_ifgroup != -1 &&
449 r->suppress_ifgroup != rule->suppress_ifgroup)
450 continue;
451
452 if (rule->suppress_prefixlen != -1 &&
453 r->suppress_prefixlen != rule->suppress_prefixlen)
454 continue;
455
456 if (rule->mark_mask && r->mark_mask != rule->mark_mask)
457 continue;
458
459 if (rule->tun_id && r->tun_id != rule->tun_id)
460 continue;
461
462 if (r->fr_net != rule->fr_net)
463 continue;
464
465 if (rule->l3mdev && r->l3mdev != rule->l3mdev)
466 continue;
467
468 if (uid_range_set(&rule->uid_range) &&
469 (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
470 !uid_eq(r->uid_range.end, rule->uid_range.end)))
471 continue;
472
473 if (rule->ip_proto && r->ip_proto != rule->ip_proto)
474 continue;
475
476 if (rule->proto && r->proto != rule->proto)
477 continue;
478
479 if (fib_rule_port_range_set(&rule->sport_range) &&
480 !fib_rule_port_range_compare(&r->sport_range,
481 &rule->sport_range))
482 continue;
483
484 if (fib_rule_port_range_set(&rule->dport_range) &&
485 !fib_rule_port_range_compare(&r->dport_range,
486 &rule->dport_range))
487 continue;
488
489 if (!ops->compare(r, frh, tb))
490 continue;
491 return r;
492 }
493
494 return NULL;
495 }
496
497 #ifdef CONFIG_NET_L3_MASTER_DEV
fib_nl2rule_l3mdev(struct nlattr * nla,struct fib_rule * nlrule,struct netlink_ext_ack * extack)498 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
499 struct netlink_ext_ack *extack)
500 {
501 nlrule->l3mdev = nla_get_u8(nla);
502 if (nlrule->l3mdev != 1) {
503 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute");
504 return -1;
505 }
506
507 return 0;
508 }
509 #else
fib_nl2rule_l3mdev(struct nlattr * nla,struct fib_rule * nlrule,struct netlink_ext_ack * extack)510 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
511 struct netlink_ext_ack *extack)
512 {
513 NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel");
514 return -1;
515 }
516 #endif
517
fib_nl2rule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack,struct fib_rules_ops * ops,struct nlattr * tb[],struct fib_rule ** rule,bool * user_priority)518 static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
519 struct netlink_ext_ack *extack,
520 struct fib_rules_ops *ops,
521 struct nlattr *tb[],
522 struct fib_rule **rule,
523 bool *user_priority)
524 {
525 struct net *net = sock_net(skb->sk);
526 struct fib_rule_hdr *frh = nlmsg_data(nlh);
527 struct fib_rule *nlrule = NULL;
528 int err = -EINVAL;
529
530 if (frh->src_len)
531 if (!tb[FRA_SRC] ||
532 frh->src_len > (ops->addr_size * 8) ||
533 nla_len(tb[FRA_SRC]) != ops->addr_size) {
534 NL_SET_ERR_MSG(extack, "Invalid source address");
535 goto errout;
536 }
537
538 if (frh->dst_len)
539 if (!tb[FRA_DST] ||
540 frh->dst_len > (ops->addr_size * 8) ||
541 nla_len(tb[FRA_DST]) != ops->addr_size) {
542 NL_SET_ERR_MSG(extack, "Invalid dst address");
543 goto errout;
544 }
545
546 nlrule = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
547 if (!nlrule) {
548 err = -ENOMEM;
549 goto errout;
550 }
551 refcount_set(&nlrule->refcnt, 1);
552 nlrule->fr_net = net;
553
554 if (tb[FRA_PRIORITY]) {
555 nlrule->pref = nla_get_u32(tb[FRA_PRIORITY]);
556 *user_priority = true;
557 } else {
558 nlrule->pref = fib_default_rule_pref(ops);
559 }
560
561 nlrule->proto = tb[FRA_PROTOCOL] ?
562 nla_get_u8(tb[FRA_PROTOCOL]) : RTPROT_UNSPEC;
563
564 if (tb[FRA_IIFNAME]) {
565 struct net_device *dev;
566
567 nlrule->iifindex = -1;
568 nla_strscpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
569 dev = __dev_get_by_name(net, nlrule->iifname);
570 if (dev)
571 nlrule->iifindex = dev->ifindex;
572 }
573
574 if (tb[FRA_OIFNAME]) {
575 struct net_device *dev;
576
577 nlrule->oifindex = -1;
578 nla_strscpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
579 dev = __dev_get_by_name(net, nlrule->oifname);
580 if (dev)
581 nlrule->oifindex = dev->ifindex;
582 }
583
584 if (tb[FRA_FWMARK]) {
585 nlrule->mark = nla_get_u32(tb[FRA_FWMARK]);
586 if (nlrule->mark)
587 /* compatibility: if the mark value is non-zero all bits
588 * are compared unless a mask is explicitly specified.
589 */
590 nlrule->mark_mask = 0xFFFFFFFF;
591 }
592
593 if (tb[FRA_FWMASK])
594 nlrule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
595
596 if (tb[FRA_TUN_ID])
597 nlrule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
598
599 if (tb[FRA_L3MDEV] &&
600 fib_nl2rule_l3mdev(tb[FRA_L3MDEV], nlrule, extack) < 0)
601 goto errout_free;
602
603 nlrule->action = frh->action;
604 nlrule->flags = frh->flags;
605 nlrule->table = frh_get_table(frh, tb);
606 if (tb[FRA_SUPPRESS_PREFIXLEN])
607 nlrule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
608 else
609 nlrule->suppress_prefixlen = -1;
610
611 if (tb[FRA_SUPPRESS_IFGROUP])
612 nlrule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
613 else
614 nlrule->suppress_ifgroup = -1;
615
616 if (tb[FRA_GOTO]) {
617 if (nlrule->action != FR_ACT_GOTO) {
618 NL_SET_ERR_MSG(extack, "Unexpected goto");
619 goto errout_free;
620 }
621
622 nlrule->target = nla_get_u32(tb[FRA_GOTO]);
623 /* Backward jumps are prohibited to avoid endless loops */
624 if (nlrule->target <= nlrule->pref) {
625 NL_SET_ERR_MSG(extack, "Backward goto not supported");
626 goto errout_free;
627 }
628 } else if (nlrule->action == FR_ACT_GOTO) {
629 NL_SET_ERR_MSG(extack, "Missing goto target for action goto");
630 goto errout_free;
631 }
632
633 if (nlrule->l3mdev && nlrule->table) {
634 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive");
635 goto errout_free;
636 }
637
638 if (tb[FRA_UID_RANGE]) {
639 if (current_user_ns() != net->user_ns) {
640 err = -EPERM;
641 NL_SET_ERR_MSG(extack, "No permission to set uid");
642 goto errout_free;
643 }
644
645 nlrule->uid_range = nla_get_kuid_range(tb);
646
647 if (!uid_range_set(&nlrule->uid_range) ||
648 !uid_lte(nlrule->uid_range.start, nlrule->uid_range.end)) {
649 NL_SET_ERR_MSG(extack, "Invalid uid range");
650 goto errout_free;
651 }
652 } else {
653 nlrule->uid_range = fib_kuid_range_unset;
654 }
655
656 if (tb[FRA_IP_PROTO])
657 nlrule->ip_proto = nla_get_u8(tb[FRA_IP_PROTO]);
658
659 if (tb[FRA_SPORT_RANGE]) {
660 err = nla_get_port_range(tb[FRA_SPORT_RANGE],
661 &nlrule->sport_range);
662 if (err) {
663 NL_SET_ERR_MSG(extack, "Invalid sport range");
664 goto errout_free;
665 }
666 }
667
668 if (tb[FRA_DPORT_RANGE]) {
669 err = nla_get_port_range(tb[FRA_DPORT_RANGE],
670 &nlrule->dport_range);
671 if (err) {
672 NL_SET_ERR_MSG(extack, "Invalid dport range");
673 goto errout_free;
674 }
675 }
676
677 *rule = nlrule;
678
679 return 0;
680
681 errout_free:
682 kfree(nlrule);
683 errout:
684 return err;
685 }
686
rule_exists(struct fib_rules_ops * ops,struct fib_rule_hdr * frh,struct nlattr ** tb,struct fib_rule * rule)687 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
688 struct nlattr **tb, struct fib_rule *rule)
689 {
690 struct fib_rule *r;
691
692 list_for_each_entry(r, &ops->rules_list, list) {
693 if (r->action != rule->action)
694 continue;
695
696 if (r->table != rule->table)
697 continue;
698
699 if (r->pref != rule->pref)
700 continue;
701
702 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
703 continue;
704
705 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
706 continue;
707
708 if (r->mark != rule->mark)
709 continue;
710
711 if (r->suppress_ifgroup != rule->suppress_ifgroup)
712 continue;
713
714 if (r->suppress_prefixlen != rule->suppress_prefixlen)
715 continue;
716
717 if (r->mark_mask != rule->mark_mask)
718 continue;
719
720 if (r->tun_id != rule->tun_id)
721 continue;
722
723 if (r->fr_net != rule->fr_net)
724 continue;
725
726 if (r->l3mdev != rule->l3mdev)
727 continue;
728
729 if (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
730 !uid_eq(r->uid_range.end, rule->uid_range.end))
731 continue;
732
733 if (r->ip_proto != rule->ip_proto)
734 continue;
735
736 if (r->proto != rule->proto)
737 continue;
738
739 if (!fib_rule_port_range_compare(&r->sport_range,
740 &rule->sport_range))
741 continue;
742
743 if (!fib_rule_port_range_compare(&r->dport_range,
744 &rule->dport_range))
745 continue;
746
747 if (!ops->compare(r, frh, tb))
748 continue;
749 return 1;
750 }
751 return 0;
752 }
753
754 static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = {
755 [FRA_UNSPEC] = { .strict_start_type = FRA_DPORT_RANGE + 1 },
756 [FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
757 [FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
758 [FRA_PRIORITY] = { .type = NLA_U32 },
759 [FRA_FWMARK] = { .type = NLA_U32 },
760 [FRA_FLOW] = { .type = NLA_U32 },
761 [FRA_TUN_ID] = { .type = NLA_U64 },
762 [FRA_FWMASK] = { .type = NLA_U32 },
763 [FRA_TABLE] = { .type = NLA_U32 },
764 [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 },
765 [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 },
766 [FRA_GOTO] = { .type = NLA_U32 },
767 [FRA_L3MDEV] = { .type = NLA_U8 },
768 [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) },
769 [FRA_PROTOCOL] = { .type = NLA_U8 },
770 [FRA_IP_PROTO] = { .type = NLA_U8 },
771 [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
772 [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
773 [FRA_DSCP] = NLA_POLICY_MAX(NLA_U8, INET_DSCP_MASK >> 2),
774 };
775
fib_nl_newrule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)776 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
777 struct netlink_ext_ack *extack)
778 {
779 struct net *net = sock_net(skb->sk);
780 struct fib_rule_hdr *frh = nlmsg_data(nlh);
781 struct fib_rules_ops *ops = NULL;
782 struct fib_rule *rule = NULL, *r, *last = NULL;
783 struct nlattr *tb[FRA_MAX + 1];
784 int err = -EINVAL, unresolved = 0;
785 bool user_priority = false;
786
787 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
788 NL_SET_ERR_MSG(extack, "Invalid msg length");
789 goto errout;
790 }
791
792 ops = lookup_rules_ops(net, frh->family);
793 if (!ops) {
794 err = -EAFNOSUPPORT;
795 NL_SET_ERR_MSG(extack, "Rule family not supported");
796 goto errout;
797 }
798
799 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
800 fib_rule_policy, extack);
801 if (err < 0) {
802 NL_SET_ERR_MSG(extack, "Error parsing msg");
803 goto errout;
804 }
805
806 err = fib_nl2rule(skb, nlh, extack, ops, tb, &rule, &user_priority);
807 if (err)
808 goto errout;
809
810 if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
811 rule_exists(ops, frh, tb, rule)) {
812 err = -EEXIST;
813 goto errout_free;
814 }
815
816 err = ops->configure(rule, skb, frh, tb, extack);
817 if (err < 0)
818 goto errout_free;
819
820 err = call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule, ops,
821 extack);
822 if (err < 0)
823 goto errout_free;
824
825 list_for_each_entry(r, &ops->rules_list, list) {
826 if (r->pref == rule->target) {
827 RCU_INIT_POINTER(rule->ctarget, r);
828 break;
829 }
830 }
831
832 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
833 unresolved = 1;
834
835 list_for_each_entry(r, &ops->rules_list, list) {
836 if (r->pref > rule->pref)
837 break;
838 last = r;
839 }
840
841 if (last)
842 list_add_rcu(&rule->list, &last->list);
843 else
844 list_add_rcu(&rule->list, &ops->rules_list);
845
846 if (ops->unresolved_rules) {
847 /*
848 * There are unresolved goto rules in the list, check if
849 * any of them are pointing to this new rule.
850 */
851 list_for_each_entry(r, &ops->rules_list, list) {
852 if (r->action == FR_ACT_GOTO &&
853 r->target == rule->pref &&
854 rtnl_dereference(r->ctarget) == NULL) {
855 rcu_assign_pointer(r->ctarget, rule);
856 if (--ops->unresolved_rules == 0)
857 break;
858 }
859 }
860 }
861
862 if (rule->action == FR_ACT_GOTO)
863 ops->nr_goto_rules++;
864
865 if (unresolved)
866 ops->unresolved_rules++;
867
868 if (rule->tun_id)
869 ip_tunnel_need_metadata();
870
871 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
872 flush_route_cache(ops);
873 rules_ops_put(ops);
874 return 0;
875
876 errout_free:
877 kfree(rule);
878 errout:
879 rules_ops_put(ops);
880 return err;
881 }
882 EXPORT_SYMBOL_GPL(fib_nl_newrule);
883
fib_nl_delrule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)884 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
885 struct netlink_ext_ack *extack)
886 {
887 struct net *net = sock_net(skb->sk);
888 struct fib_rule_hdr *frh = nlmsg_data(nlh);
889 struct fib_rules_ops *ops = NULL;
890 struct fib_rule *rule = NULL, *r, *nlrule = NULL;
891 struct nlattr *tb[FRA_MAX+1];
892 int err = -EINVAL;
893 bool user_priority = false;
894
895 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
896 NL_SET_ERR_MSG(extack, "Invalid msg length");
897 goto errout;
898 }
899
900 ops = lookup_rules_ops(net, frh->family);
901 if (ops == NULL) {
902 err = -EAFNOSUPPORT;
903 NL_SET_ERR_MSG(extack, "Rule family not supported");
904 goto errout;
905 }
906
907 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
908 fib_rule_policy, extack);
909 if (err < 0) {
910 NL_SET_ERR_MSG(extack, "Error parsing msg");
911 goto errout;
912 }
913
914 err = fib_nl2rule(skb, nlh, extack, ops, tb, &nlrule, &user_priority);
915 if (err)
916 goto errout;
917
918 rule = rule_find(ops, frh, tb, nlrule, user_priority);
919 if (!rule) {
920 err = -ENOENT;
921 goto errout;
922 }
923
924 if (rule->flags & FIB_RULE_PERMANENT) {
925 err = -EPERM;
926 goto errout;
927 }
928
929 if (ops->delete) {
930 err = ops->delete(rule);
931 if (err)
932 goto errout;
933 }
934
935 if (rule->tun_id)
936 ip_tunnel_unneed_metadata();
937
938 list_del_rcu(&rule->list);
939
940 if (rule->action == FR_ACT_GOTO) {
941 ops->nr_goto_rules--;
942 if (rtnl_dereference(rule->ctarget) == NULL)
943 ops->unresolved_rules--;
944 }
945
946 /*
947 * Check if this rule is a target to any of them. If so,
948 * adjust to the next one with the same preference or
949 * disable them. As this operation is eventually very
950 * expensive, it is only performed if goto rules, except
951 * current if it is goto rule, have actually been added.
952 */
953 if (ops->nr_goto_rules > 0) {
954 struct fib_rule *n;
955
956 n = list_next_entry(rule, list);
957 if (&n->list == &ops->rules_list || n->pref != rule->pref)
958 n = NULL;
959 list_for_each_entry(r, &ops->rules_list, list) {
960 if (rtnl_dereference(r->ctarget) != rule)
961 continue;
962 rcu_assign_pointer(r->ctarget, n);
963 if (!n)
964 ops->unresolved_rules++;
965 }
966 }
967
968 call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule, ops,
969 NULL);
970 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
971 NETLINK_CB(skb).portid);
972 fib_rule_put(rule);
973 flush_route_cache(ops);
974 rules_ops_put(ops);
975 kfree(nlrule);
976 return 0;
977
978 errout:
979 kfree(nlrule);
980 rules_ops_put(ops);
981 return err;
982 }
983 EXPORT_SYMBOL_GPL(fib_nl_delrule);
984
fib_rule_nlmsg_size(struct fib_rules_ops * ops,struct fib_rule * rule)985 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
986 struct fib_rule *rule)
987 {
988 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
989 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
990 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
991 + nla_total_size(4) /* FRA_PRIORITY */
992 + nla_total_size(4) /* FRA_TABLE */
993 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
994 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
995 + nla_total_size(4) /* FRA_FWMARK */
996 + nla_total_size(4) /* FRA_FWMASK */
997 + nla_total_size_64bit(8) /* FRA_TUN_ID */
998 + nla_total_size(sizeof(struct fib_kuid_range))
999 + nla_total_size(1) /* FRA_PROTOCOL */
1000 + nla_total_size(1) /* FRA_IP_PROTO */
1001 + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */
1002 + nla_total_size(sizeof(struct fib_rule_port_range)); /* FRA_DPORT_RANGE */
1003
1004 if (ops->nlmsg_payload)
1005 payload += ops->nlmsg_payload(rule);
1006
1007 return payload;
1008 }
1009
fib_nl_fill_rule(struct sk_buff * skb,struct fib_rule * rule,u32 pid,u32 seq,int type,int flags,struct fib_rules_ops * ops)1010 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
1011 u32 pid, u32 seq, int type, int flags,
1012 struct fib_rules_ops *ops)
1013 {
1014 struct nlmsghdr *nlh;
1015 struct fib_rule_hdr *frh;
1016
1017 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
1018 if (nlh == NULL)
1019 return -EMSGSIZE;
1020
1021 frh = nlmsg_data(nlh);
1022 frh->family = ops->family;
1023 frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT;
1024 if (nla_put_u32(skb, FRA_TABLE, rule->table))
1025 goto nla_put_failure;
1026 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
1027 goto nla_put_failure;
1028 frh->res1 = 0;
1029 frh->res2 = 0;
1030 frh->action = rule->action;
1031 frh->flags = rule->flags;
1032
1033 if (nla_put_u8(skb, FRA_PROTOCOL, rule->proto))
1034 goto nla_put_failure;
1035
1036 if (rule->action == FR_ACT_GOTO &&
1037 rcu_access_pointer(rule->ctarget) == NULL)
1038 frh->flags |= FIB_RULE_UNRESOLVED;
1039
1040 if (rule->iifname[0]) {
1041 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
1042 goto nla_put_failure;
1043 if (READ_ONCE(rule->iifindex) == -1)
1044 frh->flags |= FIB_RULE_IIF_DETACHED;
1045 }
1046
1047 if (rule->oifname[0]) {
1048 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
1049 goto nla_put_failure;
1050 if (READ_ONCE(rule->oifindex) == -1)
1051 frh->flags |= FIB_RULE_OIF_DETACHED;
1052 }
1053
1054 if ((rule->pref &&
1055 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
1056 (rule->mark &&
1057 nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
1058 ((rule->mark_mask || rule->mark) &&
1059 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
1060 (rule->target &&
1061 nla_put_u32(skb, FRA_GOTO, rule->target)) ||
1062 (rule->tun_id &&
1063 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
1064 (rule->l3mdev &&
1065 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
1066 (uid_range_set(&rule->uid_range) &&
1067 nla_put_uid_range(skb, &rule->uid_range)) ||
1068 (fib_rule_port_range_set(&rule->sport_range) &&
1069 nla_put_port_range(skb, FRA_SPORT_RANGE, &rule->sport_range)) ||
1070 (fib_rule_port_range_set(&rule->dport_range) &&
1071 nla_put_port_range(skb, FRA_DPORT_RANGE, &rule->dport_range)) ||
1072 (rule->ip_proto && nla_put_u8(skb, FRA_IP_PROTO, rule->ip_proto)))
1073 goto nla_put_failure;
1074
1075 if (rule->suppress_ifgroup != -1) {
1076 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
1077 goto nla_put_failure;
1078 }
1079
1080 if (ops->fill(rule, skb, frh) < 0)
1081 goto nla_put_failure;
1082
1083 nlmsg_end(skb, nlh);
1084 return 0;
1085
1086 nla_put_failure:
1087 nlmsg_cancel(skb, nlh);
1088 return -EMSGSIZE;
1089 }
1090
dump_rules(struct sk_buff * skb,struct netlink_callback * cb,struct fib_rules_ops * ops)1091 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
1092 struct fib_rules_ops *ops)
1093 {
1094 int idx = 0;
1095 struct fib_rule *rule;
1096 int err = 0;
1097
1098 rcu_read_lock();
1099 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
1100 if (idx < cb->args[1])
1101 goto skip;
1102
1103 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
1104 cb->nlh->nlmsg_seq, RTM_NEWRULE,
1105 NLM_F_MULTI, ops);
1106 if (err)
1107 break;
1108 skip:
1109 idx++;
1110 }
1111 rcu_read_unlock();
1112 cb->args[1] = idx;
1113 rules_ops_put(ops);
1114
1115 return err;
1116 }
1117
fib_valid_dumprule_req(const struct nlmsghdr * nlh,struct netlink_ext_ack * extack)1118 static int fib_valid_dumprule_req(const struct nlmsghdr *nlh,
1119 struct netlink_ext_ack *extack)
1120 {
1121 struct fib_rule_hdr *frh;
1122
1123 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
1124 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request");
1125 return -EINVAL;
1126 }
1127
1128 frh = nlmsg_data(nlh);
1129 if (frh->dst_len || frh->src_len || frh->tos || frh->table ||
1130 frh->res1 || frh->res2 || frh->action || frh->flags) {
1131 NL_SET_ERR_MSG(extack,
1132 "Invalid values in header for fib rule dump request");
1133 return -EINVAL;
1134 }
1135
1136 if (nlmsg_attrlen(nlh, sizeof(*frh))) {
1137 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request");
1138 return -EINVAL;
1139 }
1140
1141 return 0;
1142 }
1143
fib_nl_dumprule(struct sk_buff * skb,struct netlink_callback * cb)1144 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
1145 {
1146 const struct nlmsghdr *nlh = cb->nlh;
1147 struct net *net = sock_net(skb->sk);
1148 struct fib_rules_ops *ops;
1149 int idx = 0, family;
1150
1151 if (cb->strict_check) {
1152 int err = fib_valid_dumprule_req(nlh, cb->extack);
1153
1154 if (err < 0)
1155 return err;
1156 }
1157
1158 family = rtnl_msg_family(nlh);
1159 if (family != AF_UNSPEC) {
1160 /* Protocol specific dump request */
1161 ops = lookup_rules_ops(net, family);
1162 if (ops == NULL)
1163 return -EAFNOSUPPORT;
1164
1165 dump_rules(skb, cb, ops);
1166
1167 return skb->len;
1168 }
1169
1170 rcu_read_lock();
1171 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
1172 if (idx < cb->args[0] || !try_module_get(ops->owner))
1173 goto skip;
1174
1175 if (dump_rules(skb, cb, ops) < 0)
1176 break;
1177
1178 cb->args[1] = 0;
1179 skip:
1180 idx++;
1181 }
1182 rcu_read_unlock();
1183 cb->args[0] = idx;
1184
1185 return skb->len;
1186 }
1187
notify_rule_change(int event,struct fib_rule * rule,struct fib_rules_ops * ops,struct nlmsghdr * nlh,u32 pid)1188 static void notify_rule_change(int event, struct fib_rule *rule,
1189 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
1190 u32 pid)
1191 {
1192 struct net *net;
1193 struct sk_buff *skb;
1194 int err = -ENOMEM;
1195
1196 net = ops->fro_net;
1197 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
1198 if (skb == NULL)
1199 goto errout;
1200
1201 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
1202 if (err < 0) {
1203 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
1204 WARN_ON(err == -EMSGSIZE);
1205 kfree_skb(skb);
1206 goto errout;
1207 }
1208
1209 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
1210 return;
1211 errout:
1212 rtnl_set_sk_err(net, ops->nlgroup, err);
1213 }
1214
attach_rules(struct list_head * rules,struct net_device * dev)1215 static void attach_rules(struct list_head *rules, struct net_device *dev)
1216 {
1217 struct fib_rule *rule;
1218
1219 list_for_each_entry(rule, rules, list) {
1220 if (rule->iifindex == -1 &&
1221 strcmp(dev->name, rule->iifname) == 0)
1222 WRITE_ONCE(rule->iifindex, dev->ifindex);
1223 if (rule->oifindex == -1 &&
1224 strcmp(dev->name, rule->oifname) == 0)
1225 WRITE_ONCE(rule->oifindex, dev->ifindex);
1226 }
1227 }
1228
detach_rules(struct list_head * rules,struct net_device * dev)1229 static void detach_rules(struct list_head *rules, struct net_device *dev)
1230 {
1231 struct fib_rule *rule;
1232
1233 list_for_each_entry(rule, rules, list) {
1234 if (rule->iifindex == dev->ifindex)
1235 WRITE_ONCE(rule->iifindex, -1);
1236 if (rule->oifindex == dev->ifindex)
1237 WRITE_ONCE(rule->oifindex, -1);
1238 }
1239 }
1240
1241
fib_rules_event(struct notifier_block * this,unsigned long event,void * ptr)1242 static int fib_rules_event(struct notifier_block *this, unsigned long event,
1243 void *ptr)
1244 {
1245 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1246 struct net *net = dev_net(dev);
1247 struct fib_rules_ops *ops;
1248
1249 ASSERT_RTNL();
1250
1251 switch (event) {
1252 case NETDEV_REGISTER:
1253 list_for_each_entry(ops, &net->rules_ops, list)
1254 attach_rules(&ops->rules_list, dev);
1255 break;
1256
1257 case NETDEV_CHANGENAME:
1258 list_for_each_entry(ops, &net->rules_ops, list) {
1259 detach_rules(&ops->rules_list, dev);
1260 attach_rules(&ops->rules_list, dev);
1261 }
1262 break;
1263
1264 case NETDEV_UNREGISTER:
1265 list_for_each_entry(ops, &net->rules_ops, list)
1266 detach_rules(&ops->rules_list, dev);
1267 break;
1268 }
1269
1270 return NOTIFY_DONE;
1271 }
1272
1273 static struct notifier_block fib_rules_notifier = {
1274 .notifier_call = fib_rules_event,
1275 };
1276
fib_rules_net_init(struct net * net)1277 static int __net_init fib_rules_net_init(struct net *net)
1278 {
1279 INIT_LIST_HEAD(&net->rules_ops);
1280 spin_lock_init(&net->rules_mod_lock);
1281 return 0;
1282 }
1283
fib_rules_net_exit(struct net * net)1284 static void __net_exit fib_rules_net_exit(struct net *net)
1285 {
1286 WARN_ON_ONCE(!list_empty(&net->rules_ops));
1287 }
1288
1289 static struct pernet_operations fib_rules_net_ops = {
1290 .init = fib_rules_net_init,
1291 .exit = fib_rules_net_exit,
1292 };
1293
fib_rules_init(void)1294 static int __init fib_rules_init(void)
1295 {
1296 int err;
1297 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, 0);
1298 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, 0);
1299 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, 0);
1300
1301 err = register_pernet_subsys(&fib_rules_net_ops);
1302 if (err < 0)
1303 goto fail;
1304
1305 err = register_netdevice_notifier(&fib_rules_notifier);
1306 if (err < 0)
1307 goto fail_unregister;
1308
1309 return 0;
1310
1311 fail_unregister:
1312 unregister_pernet_subsys(&fib_rules_net_ops);
1313 fail:
1314 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
1315 rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
1316 rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
1317 return err;
1318 }
1319
1320 subsys_initcall(fib_rules_init);
1321