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
33static const struct fib_kuid_range fib_kuid_range_unset = {
34 KUIDT_INIT(0),
35 KUIDT_INIT(~0),
36};
37
38bool 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(left: rule->uid_range.start, right: fib_kuid_range_unset.start) ||
46 !uid_eq(left: rule->uid_range.end, right: fib_kuid_range_unset.end))
47 return false;
48 if (fib_rule_port_range_set(range: &rule->sport_range))
49 return false;
50 if (fib_rule_port_range_set(range: &rule->dport_range))
51 return false;
52 return true;
53}
54EXPORT_SYMBOL_GPL(fib_rule_matchall);
55
56int 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: &r->refcnt, n: 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(new: &r->list, head: &ops->rules_list);
79 return 0;
80}
81EXPORT_SYMBOL(fib_default_rule_add);
82
83static 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(head: &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
100static void notify_rule_change(int event, struct fib_rule *rule,
101 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
102 u32 pid);
103
104static struct fib_rules_ops *lookup_rules_ops(const struct net *net,
105 int family)
106{
107 struct fib_rules_ops *ops;
108
109 rcu_read_lock();
110 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
111 if (ops->family == family) {
112 if (!try_module_get(module: ops->owner))
113 ops = NULL;
114 rcu_read_unlock();
115 return ops;
116 }
117 }
118 rcu_read_unlock();
119
120 return NULL;
121}
122
123static void rules_ops_put(struct fib_rules_ops *ops)
124{
125 if (ops)
126 module_put(module: ops->owner);
127}
128
129static void flush_route_cache(struct fib_rules_ops *ops)
130{
131 if (ops->flush_cache)
132 ops->flush_cache(ops);
133}
134
135static int __fib_rules_register(struct fib_rules_ops *ops)
136{
137 int err = -EEXIST;
138 struct fib_rules_ops *o;
139 struct net *net;
140
141 net = ops->fro_net;
142
143 if (ops->rule_size < sizeof(struct fib_rule))
144 return -EINVAL;
145
146 if (ops->match == NULL || ops->configure == NULL ||
147 ops->compare == NULL || ops->fill == NULL ||
148 ops->action == NULL)
149 return -EINVAL;
150
151 spin_lock(lock: &net->rules_mod_lock);
152 list_for_each_entry(o, &net->rules_ops, list)
153 if (ops->family == o->family)
154 goto errout;
155
156 list_add_tail_rcu(new: &ops->list, head: &net->rules_ops);
157 err = 0;
158errout:
159 spin_unlock(lock: &net->rules_mod_lock);
160
161 return err;
162}
163
164struct fib_rules_ops *
165fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
166{
167 struct fib_rules_ops *ops;
168 int err;
169
170 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
171 if (ops == NULL)
172 return ERR_PTR(error: -ENOMEM);
173
174 INIT_LIST_HEAD(list: &ops->rules_list);
175 ops->fro_net = net;
176
177 err = __fib_rules_register(ops);
178 if (err) {
179 kfree(objp: ops);
180 ops = ERR_PTR(error: err);
181 }
182
183 return ops;
184}
185EXPORT_SYMBOL_GPL(fib_rules_register);
186
187static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
188{
189 struct fib_rule *rule, *tmp;
190
191 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
192 list_del_rcu(entry: &rule->list);
193 if (ops->delete)
194 ops->delete(rule);
195 fib_rule_put(rule);
196 }
197}
198
199void fib_rules_unregister(struct fib_rules_ops *ops)
200{
201 struct net *net = ops->fro_net;
202
203 spin_lock(lock: &net->rules_mod_lock);
204 list_del_rcu(entry: &ops->list);
205 spin_unlock(lock: &net->rules_mod_lock);
206
207 fib_rules_cleanup_ops(ops);
208 kfree_rcu(ops, rcu);
209}
210EXPORT_SYMBOL_GPL(fib_rules_unregister);
211
212static int uid_range_set(struct fib_kuid_range *range)
213{
214 return uid_valid(uid: range->start) && uid_valid(uid: range->end);
215}
216
217static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
218{
219 struct fib_rule_uid_range *in;
220 struct fib_kuid_range out;
221
222 in = (struct fib_rule_uid_range *)nla_data(nla: tb[FRA_UID_RANGE]);
223
224 out.start = make_kuid(from: current_user_ns(), uid: in->start);
225 out.end = make_kuid(from: current_user_ns(), uid: in->end);
226
227 return out;
228}
229
230static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
231{
232 struct fib_rule_uid_range out = {
233 from_kuid_munged(to: current_user_ns(), kuid: range->start),
234 from_kuid_munged(to: current_user_ns(), kuid: range->end)
235 };
236
237 return nla_put(skb, attrtype: FRA_UID_RANGE, attrlen: sizeof(out), data: &out);
238}
239
240static int nla_get_port_range(struct nlattr *pattr,
241 struct fib_rule_port_range *port_range)
242{
243 const struct fib_rule_port_range *pr = nla_data(nla: pattr);
244
245 if (!fib_rule_port_range_valid(a: pr))
246 return -EINVAL;
247
248 port_range->start = pr->start;
249 port_range->end = pr->end;
250
251 return 0;
252}
253
254static int nla_put_port_range(struct sk_buff *skb, int attrtype,
255 struct fib_rule_port_range *range)
256{
257 return nla_put(skb, attrtype, attrlen: sizeof(*range), data: range);
258}
259
260static bool fib_rule_iif_match(const struct fib_rule *rule, int iifindex,
261 const struct flowi *fl)
262{
263 u8 iif_is_l3_master = READ_ONCE(rule->iif_is_l3_master);
264
265 return iif_is_l3_master ? l3mdev_fib_rule_iif_match(fl, iifindex) :
266 fl->flowi_iif == iifindex;
267}
268
269static bool fib_rule_oif_match(const struct fib_rule *rule, int oifindex,
270 const struct flowi *fl)
271{
272 u8 oif_is_l3_master = READ_ONCE(rule->oif_is_l3_master);
273
274 return oif_is_l3_master ? l3mdev_fib_rule_oif_match(fl, oifindex) :
275 fl->flowi_oif == oifindex;
276}
277
278static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
279 struct flowi *fl, int flags,
280 struct fib_lookup_arg *arg)
281{
282 int iifindex, oifindex, ret = 0;
283
284 iifindex = READ_ONCE(rule->iifindex);
285 if (iifindex && !fib_rule_iif_match(rule, iifindex, fl))
286 goto out;
287
288 oifindex = READ_ONCE(rule->oifindex);
289 if (oifindex && !fib_rule_oif_match(rule, oifindex, fl))
290 goto out;
291
292 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
293 goto out;
294
295 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
296 goto out;
297
298 if (rule->l3mdev && !l3mdev_fib_rule_match(net: rule->fr_net, fl, arg))
299 goto out;
300
301 if (uid_lt(left: fl->flowi_uid, right: rule->uid_range.start) ||
302 uid_gt(left: fl->flowi_uid, right: rule->uid_range.end))
303 goto out;
304
305 ret = INDIRECT_CALL_MT(ops->match,
306 fib6_rule_match,
307 fib4_rule_match,
308 rule, fl, flags);
309out:
310 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
311}
312
313int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
314 int flags, struct fib_lookup_arg *arg)
315{
316 struct fib_rule *rule;
317 int err;
318
319 rcu_read_lock();
320
321 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
322jumped:
323 if (!fib_rule_match(rule, ops, fl, flags, arg))
324 continue;
325
326 if (rule->action == FR_ACT_GOTO) {
327 struct fib_rule *target;
328
329 target = rcu_dereference(rule->ctarget);
330 if (target == NULL) {
331 continue;
332 } else {
333 rule = target;
334 goto jumped;
335 }
336 } else if (rule->action == FR_ACT_NOP)
337 continue;
338 else
339 err = INDIRECT_CALL_MT(ops->action,
340 fib6_rule_action,
341 fib4_rule_action,
342 rule, fl, flags, arg);
343
344 if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress,
345 fib6_rule_suppress,
346 fib4_rule_suppress,
347 rule, flags, arg))
348 continue;
349
350 if (err != -EAGAIN) {
351 if ((arg->flags & FIB_LOOKUP_NOREF) ||
352 likely(refcount_inc_not_zero(&rule->refcnt))) {
353 arg->rule = rule;
354 goto out;
355 }
356 break;
357 }
358 }
359
360 err = -ESRCH;
361out:
362 rcu_read_unlock();
363
364 return err;
365}
366EXPORT_SYMBOL_GPL(fib_rules_lookup);
367
368static int call_fib_rule_notifier(struct notifier_block *nb,
369 enum fib_event_type event_type,
370 struct fib_rule *rule, int family,
371 struct netlink_ext_ack *extack)
372{
373 struct fib_rule_notifier_info info = {
374 .info.family = family,
375 .info.extack = extack,
376 .rule = rule,
377 };
378
379 return call_fib_notifier(nb, event_type, info: &info.info);
380}
381
382static int call_fib_rule_notifiers(struct net *net,
383 enum fib_event_type event_type,
384 struct fib_rule *rule,
385 struct fib_rules_ops *ops,
386 struct netlink_ext_ack *extack)
387{
388 struct fib_rule_notifier_info info = {
389 .info.family = ops->family,
390 .info.extack = extack,
391 .rule = rule,
392 };
393
394 ASSERT_RTNL_NET(net);
395
396 /* Paired with READ_ONCE() in fib_rules_seq() */
397 WRITE_ONCE(ops->fib_rules_seq, ops->fib_rules_seq + 1);
398 return call_fib_notifiers(net, event_type, info: &info.info);
399}
400
401/* Called with rcu_read_lock() */
402int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
403 struct netlink_ext_ack *extack)
404{
405 struct fib_rules_ops *ops;
406 struct fib_rule *rule;
407 int err = 0;
408
409 ops = lookup_rules_ops(net, family);
410 if (!ops)
411 return -EAFNOSUPPORT;
412 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
413 err = call_fib_rule_notifier(nb, event_type: FIB_EVENT_RULE_ADD,
414 rule, family, extack);
415 if (err)
416 break;
417 }
418 rules_ops_put(ops);
419
420 return err;
421}
422EXPORT_SYMBOL_GPL(fib_rules_dump);
423
424unsigned int fib_rules_seq_read(const struct net *net, int family)
425{
426 unsigned int fib_rules_seq;
427 struct fib_rules_ops *ops;
428
429 ops = lookup_rules_ops(net, family);
430 if (!ops)
431 return 0;
432 /* Paired with WRITE_ONCE() in call_fib_rule_notifiers() */
433 fib_rules_seq = READ_ONCE(ops->fib_rules_seq);
434 rules_ops_put(ops);
435
436 return fib_rules_seq;
437}
438EXPORT_SYMBOL_GPL(fib_rules_seq_read);
439
440static struct fib_rule *rule_find(struct fib_rules_ops *ops,
441 struct fib_rule_hdr *frh,
442 struct nlattr **tb,
443 struct fib_rule *rule,
444 bool user_priority)
445{
446 struct fib_rule *r;
447
448 list_for_each_entry(r, &ops->rules_list, list) {
449 if (rule->action && r->action != rule->action)
450 continue;
451
452 if (rule->table && r->table != rule->table)
453 continue;
454
455 if (user_priority && r->pref != rule->pref)
456 continue;
457
458 if (rule->iifname[0] &&
459 memcmp(r->iifname, rule->iifname, IFNAMSIZ))
460 continue;
461
462 if (rule->oifname[0] &&
463 memcmp(r->oifname, rule->oifname, IFNAMSIZ))
464 continue;
465
466 if (rule->mark && r->mark != rule->mark)
467 continue;
468
469 if (rule->suppress_ifgroup != -1 &&
470 r->suppress_ifgroup != rule->suppress_ifgroup)
471 continue;
472
473 if (rule->suppress_prefixlen != -1 &&
474 r->suppress_prefixlen != rule->suppress_prefixlen)
475 continue;
476
477 if (rule->mark_mask && r->mark_mask != rule->mark_mask)
478 continue;
479
480 if (rule->tun_id && r->tun_id != rule->tun_id)
481 continue;
482
483 if (rule->l3mdev && r->l3mdev != rule->l3mdev)
484 continue;
485
486 if (uid_range_set(range: &rule->uid_range) &&
487 (!uid_eq(left: r->uid_range.start, right: rule->uid_range.start) ||
488 !uid_eq(left: r->uid_range.end, right: rule->uid_range.end)))
489 continue;
490
491 if (rule->ip_proto && r->ip_proto != rule->ip_proto)
492 continue;
493
494 if (rule->proto && r->proto != rule->proto)
495 continue;
496
497 if (fib_rule_port_range_set(range: &rule->sport_range) &&
498 !fib_rule_port_range_compare(a: &r->sport_range,
499 b: &rule->sport_range))
500 continue;
501
502 if (rule->sport_mask && r->sport_mask != rule->sport_mask)
503 continue;
504
505 if (fib_rule_port_range_set(range: &rule->dport_range) &&
506 !fib_rule_port_range_compare(a: &r->dport_range,
507 b: &rule->dport_range))
508 continue;
509
510 if (rule->dport_mask && r->dport_mask != rule->dport_mask)
511 continue;
512
513 if (!ops->compare(r, frh, tb))
514 continue;
515 return r;
516 }
517
518 return NULL;
519}
520
521#ifdef CONFIG_NET_L3_MASTER_DEV
522static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
523 struct netlink_ext_ack *extack)
524{
525 nlrule->l3mdev = nla_get_u8(nla);
526 if (nlrule->l3mdev != 1) {
527 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute");
528 return -1;
529 }
530
531 return 0;
532}
533#else
534static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
535 struct netlink_ext_ack *extack)
536{
537 NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel");
538 return -1;
539}
540#endif
541
542static int fib_nl2rule_port_mask(const struct nlattr *mask_attr,
543 const struct fib_rule_port_range *range,
544 u16 *port_mask,
545 struct netlink_ext_ack *extack)
546{
547 if (!fib_rule_port_range_valid(a: range)) {
548 NL_SET_ERR_MSG_ATTR(extack, mask_attr,
549 "Cannot specify port mask without port value");
550 return -EINVAL;
551 }
552
553 if (fib_rule_port_is_range(range)) {
554 NL_SET_ERR_MSG_ATTR(extack, mask_attr,
555 "Cannot specify port mask for port range");
556 return -EINVAL;
557 }
558
559 if (range->start & ~nla_get_u16(nla: mask_attr)) {
560 NL_SET_ERR_MSG_ATTR(extack, mask_attr, "Invalid port mask");
561 return -EINVAL;
562 }
563
564 *port_mask = nla_get_u16(nla: mask_attr);
565
566 return 0;
567}
568
569static int fib_nl2rule(struct net *net, struct nlmsghdr *nlh,
570 struct netlink_ext_ack *extack,
571 struct fib_rules_ops *ops,
572 struct nlattr *tb[],
573 struct fib_rule **rule,
574 bool *user_priority)
575{
576 struct fib_rule_hdr *frh = nlmsg_data(nlh);
577 struct fib_rule *nlrule = NULL;
578 int err = -EINVAL;
579
580 if (frh->src_len)
581 if (!tb[FRA_SRC] ||
582 frh->src_len > (ops->addr_size * 8) ||
583 nla_len(nla: tb[FRA_SRC]) != ops->addr_size) {
584 NL_SET_ERR_MSG(extack, "Invalid source address");
585 goto errout;
586 }
587
588 if (frh->dst_len)
589 if (!tb[FRA_DST] ||
590 frh->dst_len > (ops->addr_size * 8) ||
591 nla_len(nla: tb[FRA_DST]) != ops->addr_size) {
592 NL_SET_ERR_MSG(extack, "Invalid dst address");
593 goto errout;
594 }
595
596 nlrule = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
597 if (!nlrule) {
598 err = -ENOMEM;
599 goto errout;
600 }
601 refcount_set(r: &nlrule->refcnt, n: 1);
602 nlrule->fr_net = net;
603
604 if (tb[FRA_PRIORITY]) {
605 nlrule->pref = nla_get_u32(nla: tb[FRA_PRIORITY]);
606 *user_priority = true;
607 }
608
609 nlrule->proto = nla_get_u8_default(nla: tb[FRA_PROTOCOL], RTPROT_UNSPEC);
610
611 if (tb[FRA_IIFNAME]) {
612 nlrule->iifindex = -1;
613 nla_strscpy(dst: nlrule->iifname, nla: tb[FRA_IIFNAME], IFNAMSIZ);
614 }
615
616 if (tb[FRA_OIFNAME]) {
617 nlrule->oifindex = -1;
618 nla_strscpy(dst: nlrule->oifname, nla: tb[FRA_OIFNAME], IFNAMSIZ);
619 }
620
621 if (tb[FRA_FWMARK]) {
622 nlrule->mark = nla_get_u32(nla: tb[FRA_FWMARK]);
623 if (nlrule->mark)
624 /* compatibility: if the mark value is non-zero all bits
625 * are compared unless a mask is explicitly specified.
626 */
627 nlrule->mark_mask = 0xFFFFFFFF;
628 }
629
630 if (tb[FRA_FWMASK])
631 nlrule->mark_mask = nla_get_u32(nla: tb[FRA_FWMASK]);
632
633 if (tb[FRA_TUN_ID])
634 nlrule->tun_id = nla_get_be64(nla: tb[FRA_TUN_ID]);
635
636 if (tb[FRA_L3MDEV] &&
637 fib_nl2rule_l3mdev(nla: tb[FRA_L3MDEV], nlrule, extack) < 0)
638 goto errout_free;
639
640 nlrule->action = frh->action;
641 nlrule->flags = frh->flags;
642 nlrule->table = frh_get_table(frh, nla: tb);
643 if (tb[FRA_SUPPRESS_PREFIXLEN])
644 nlrule->suppress_prefixlen = nla_get_u32(nla: tb[FRA_SUPPRESS_PREFIXLEN]);
645 else
646 nlrule->suppress_prefixlen = -1;
647
648 if (tb[FRA_SUPPRESS_IFGROUP])
649 nlrule->suppress_ifgroup = nla_get_u32(nla: tb[FRA_SUPPRESS_IFGROUP]);
650 else
651 nlrule->suppress_ifgroup = -1;
652
653 if (tb[FRA_GOTO]) {
654 if (nlrule->action != FR_ACT_GOTO) {
655 NL_SET_ERR_MSG(extack, "Unexpected goto");
656 goto errout_free;
657 }
658
659 nlrule->target = nla_get_u32(nla: tb[FRA_GOTO]);
660 } else if (nlrule->action == FR_ACT_GOTO) {
661 NL_SET_ERR_MSG(extack, "Missing goto target for action goto");
662 goto errout_free;
663 }
664
665 if (nlrule->l3mdev && nlrule->table) {
666 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive");
667 goto errout_free;
668 }
669
670 if (tb[FRA_UID_RANGE]) {
671 if (current_user_ns() != net->user_ns) {
672 err = -EPERM;
673 NL_SET_ERR_MSG(extack, "No permission to set uid");
674 goto errout_free;
675 }
676
677 nlrule->uid_range = nla_get_kuid_range(tb);
678
679 if (!uid_range_set(range: &nlrule->uid_range) ||
680 !uid_lte(left: nlrule->uid_range.start, right: nlrule->uid_range.end)) {
681 NL_SET_ERR_MSG(extack, "Invalid uid range");
682 goto errout_free;
683 }
684 } else {
685 nlrule->uid_range = fib_kuid_range_unset;
686 }
687
688 if (tb[FRA_IP_PROTO])
689 nlrule->ip_proto = nla_get_u8(nla: tb[FRA_IP_PROTO]);
690
691 if (tb[FRA_SPORT_RANGE]) {
692 err = nla_get_port_range(pattr: tb[FRA_SPORT_RANGE],
693 port_range: &nlrule->sport_range);
694 if (err) {
695 NL_SET_ERR_MSG(extack, "Invalid sport range");
696 goto errout_free;
697 }
698 if (!fib_rule_port_is_range(range: &nlrule->sport_range))
699 nlrule->sport_mask = U16_MAX;
700 }
701
702 if (tb[FRA_SPORT_MASK]) {
703 err = fib_nl2rule_port_mask(mask_attr: tb[FRA_SPORT_MASK],
704 range: &nlrule->sport_range,
705 port_mask: &nlrule->sport_mask, extack);
706 if (err)
707 goto errout_free;
708 }
709
710 if (tb[FRA_DPORT_RANGE]) {
711 err = nla_get_port_range(pattr: tb[FRA_DPORT_RANGE],
712 port_range: &nlrule->dport_range);
713 if (err) {
714 NL_SET_ERR_MSG(extack, "Invalid dport range");
715 goto errout_free;
716 }
717 if (!fib_rule_port_is_range(range: &nlrule->dport_range))
718 nlrule->dport_mask = U16_MAX;
719 }
720
721 if (tb[FRA_DPORT_MASK]) {
722 err = fib_nl2rule_port_mask(mask_attr: tb[FRA_DPORT_MASK],
723 range: &nlrule->dport_range,
724 port_mask: &nlrule->dport_mask, extack);
725 if (err)
726 goto errout_free;
727 }
728
729 *rule = nlrule;
730
731 return 0;
732
733errout_free:
734 kfree(objp: nlrule);
735errout:
736 return err;
737}
738
739static int fib_nl2rule_rtnl(struct fib_rule *nlrule,
740 struct fib_rules_ops *ops,
741 struct nlattr *tb[],
742 struct netlink_ext_ack *extack)
743{
744 if (!tb[FRA_PRIORITY])
745 nlrule->pref = fib_default_rule_pref(ops);
746
747 /* Backward jumps are prohibited to avoid endless loops */
748 if (tb[FRA_GOTO] && nlrule->target <= nlrule->pref) {
749 NL_SET_ERR_MSG(extack, "Backward goto not supported");
750 return -EINVAL;
751 }
752
753 if (tb[FRA_IIFNAME]) {
754 struct net_device *dev;
755
756 dev = __dev_get_by_name(net: nlrule->fr_net, name: nlrule->iifname);
757 if (dev) {
758 nlrule->iifindex = dev->ifindex;
759 nlrule->iif_is_l3_master = netif_is_l3_master(dev);
760 }
761 }
762
763 if (tb[FRA_OIFNAME]) {
764 struct net_device *dev;
765
766 dev = __dev_get_by_name(net: nlrule->fr_net, name: nlrule->oifname);
767 if (dev) {
768 nlrule->oifindex = dev->ifindex;
769 nlrule->oif_is_l3_master = netif_is_l3_master(dev);
770 }
771 }
772
773 return 0;
774}
775
776static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
777 struct nlattr **tb, struct fib_rule *rule)
778{
779 struct fib_rule *r;
780
781 list_for_each_entry(r, &ops->rules_list, list) {
782 if (r->action != rule->action)
783 continue;
784
785 if (r->table != rule->table)
786 continue;
787
788 if (r->pref != rule->pref)
789 continue;
790
791 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
792 continue;
793
794 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
795 continue;
796
797 if (r->mark != rule->mark)
798 continue;
799
800 if (r->suppress_ifgroup != rule->suppress_ifgroup)
801 continue;
802
803 if (r->suppress_prefixlen != rule->suppress_prefixlen)
804 continue;
805
806 if (r->mark_mask != rule->mark_mask)
807 continue;
808
809 if (r->tun_id != rule->tun_id)
810 continue;
811
812 if (r->l3mdev != rule->l3mdev)
813 continue;
814
815 if (!uid_eq(left: r->uid_range.start, right: rule->uid_range.start) ||
816 !uid_eq(left: r->uid_range.end, right: rule->uid_range.end))
817 continue;
818
819 if (r->ip_proto != rule->ip_proto)
820 continue;
821
822 if (r->proto != rule->proto)
823 continue;
824
825 if (!fib_rule_port_range_compare(a: &r->sport_range,
826 b: &rule->sport_range))
827 continue;
828
829 if (r->sport_mask != rule->sport_mask)
830 continue;
831
832 if (!fib_rule_port_range_compare(a: &r->dport_range,
833 b: &rule->dport_range))
834 continue;
835
836 if (r->dport_mask != rule->dport_mask)
837 continue;
838
839 if (!ops->compare(r, frh, tb))
840 continue;
841 return 1;
842 }
843 return 0;
844}
845
846static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = {
847 [FRA_UNSPEC] = { .strict_start_type = FRA_DPORT_RANGE + 1 },
848 [FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
849 [FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
850 [FRA_PRIORITY] = { .type = NLA_U32 },
851 [FRA_FWMARK] = { .type = NLA_U32 },
852 [FRA_FLOW] = { .type = NLA_U32 },
853 [FRA_TUN_ID] = { .type = NLA_U64 },
854 [FRA_FWMASK] = { .type = NLA_U32 },
855 [FRA_TABLE] = { .type = NLA_U32 },
856 [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 },
857 [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 },
858 [FRA_GOTO] = { .type = NLA_U32 },
859 [FRA_L3MDEV] = { .type = NLA_U8 },
860 [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) },
861 [FRA_PROTOCOL] = { .type = NLA_U8 },
862 [FRA_IP_PROTO] = { .type = NLA_U8 },
863 [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
864 [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
865 [FRA_DSCP] = NLA_POLICY_MAX(NLA_U8, INET_DSCP_MASK >> 2),
866 [FRA_FLOWLABEL] = { .type = NLA_BE32 },
867 [FRA_FLOWLABEL_MASK] = { .type = NLA_BE32 },
868 [FRA_SPORT_MASK] = { .type = NLA_U16 },
869 [FRA_DPORT_MASK] = { .type = NLA_U16 },
870 [FRA_DSCP_MASK] = NLA_POLICY_MASK(NLA_U8, INET_DSCP_MASK >> 2),
871};
872
873int fib_newrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh,
874 struct netlink_ext_ack *extack, bool rtnl_held)
875{
876 struct fib_rule *rule = NULL, *r, *last = NULL;
877 int err = -EINVAL, unresolved = 0;
878 struct fib_rules_ops *ops = NULL;
879 struct nlattr *tb[FRA_MAX + 1];
880 bool user_priority = false;
881 struct fib_rule_hdr *frh;
882
883 frh = nlmsg_payload(nlh, len: sizeof(*frh));
884 if (!frh) {
885 NL_SET_ERR_MSG(extack, "Invalid msg length");
886 goto errout;
887 }
888
889 ops = lookup_rules_ops(net, family: frh->family);
890 if (!ops) {
891 err = -EAFNOSUPPORT;
892 NL_SET_ERR_MSG(extack, "Rule family not supported");
893 goto errout;
894 }
895
896 err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*frh), tb, FRA_MAX,
897 policy: fib_rule_policy, extack);
898 if (err < 0) {
899 NL_SET_ERR_MSG(extack, "Error parsing msg");
900 goto errout;
901 }
902
903 err = fib_nl2rule(net, nlh, extack, ops, tb, rule: &rule, user_priority: &user_priority);
904 if (err)
905 goto errout;
906
907 if (!rtnl_held)
908 rtnl_net_lock(net);
909
910 err = fib_nl2rule_rtnl(nlrule: rule, ops, tb, extack);
911 if (err)
912 goto errout_free;
913
914 if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
915 rule_exists(ops, frh, tb, rule)) {
916 err = -EEXIST;
917 goto errout_free;
918 }
919
920 err = ops->configure(rule, skb, frh, tb, extack);
921 if (err < 0)
922 goto errout_free;
923
924 err = call_fib_rule_notifiers(net, event_type: FIB_EVENT_RULE_ADD, rule, ops,
925 extack);
926 if (err < 0)
927 goto errout_free;
928
929 list_for_each_entry(r, &ops->rules_list, list) {
930 if (r->pref == rule->target) {
931 RCU_INIT_POINTER(rule->ctarget, r);
932 break;
933 }
934 }
935
936 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
937 unresolved = 1;
938
939 list_for_each_entry(r, &ops->rules_list, list) {
940 if (r->pref > rule->pref)
941 break;
942 last = r;
943 }
944
945 if (last)
946 list_add_rcu(new: &rule->list, head: &last->list);
947 else
948 list_add_rcu(new: &rule->list, head: &ops->rules_list);
949
950 if (ops->unresolved_rules) {
951 /*
952 * There are unresolved goto rules in the list, check if
953 * any of them are pointing to this new rule.
954 */
955 list_for_each_entry(r, &ops->rules_list, list) {
956 if (r->action == FR_ACT_GOTO &&
957 r->target == rule->pref &&
958 rtnl_dereference(r->ctarget) == NULL) {
959 rcu_assign_pointer(r->ctarget, rule);
960 if (--ops->unresolved_rules == 0)
961 break;
962 }
963 }
964 }
965
966 if (rule->action == FR_ACT_GOTO)
967 ops->nr_goto_rules++;
968
969 if (unresolved)
970 ops->unresolved_rules++;
971
972 if (rule->tun_id)
973 ip_tunnel_need_metadata();
974
975 fib_rule_get(rule);
976
977 if (!rtnl_held)
978 rtnl_net_unlock(net);
979
980 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
981 fib_rule_put(rule);
982 flush_route_cache(ops);
983 rules_ops_put(ops);
984 return 0;
985
986errout_free:
987 if (!rtnl_held)
988 rtnl_net_unlock(net);
989 kfree(objp: rule);
990errout:
991 rules_ops_put(ops);
992 return err;
993}
994EXPORT_SYMBOL_GPL(fib_newrule);
995
996static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
997 struct netlink_ext_ack *extack)
998{
999 return fib_newrule(sock_net(sk: skb->sk), skb, nlh, extack, false);
1000}
1001
1002int fib_delrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh,
1003 struct netlink_ext_ack *extack, bool rtnl_held)
1004{
1005 struct fib_rule *rule = NULL, *nlrule = NULL;
1006 struct fib_rules_ops *ops = NULL;
1007 struct nlattr *tb[FRA_MAX+1];
1008 bool user_priority = false;
1009 struct fib_rule_hdr *frh;
1010 int err = -EINVAL;
1011
1012 frh = nlmsg_payload(nlh, len: sizeof(*frh));
1013 if (!frh) {
1014 NL_SET_ERR_MSG(extack, "Invalid msg length");
1015 goto errout;
1016 }
1017
1018 ops = lookup_rules_ops(net, family: frh->family);
1019 if (ops == NULL) {
1020 err = -EAFNOSUPPORT;
1021 NL_SET_ERR_MSG(extack, "Rule family not supported");
1022 goto errout;
1023 }
1024
1025 err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*frh), tb, FRA_MAX,
1026 policy: fib_rule_policy, extack);
1027 if (err < 0) {
1028 NL_SET_ERR_MSG(extack, "Error parsing msg");
1029 goto errout;
1030 }
1031
1032 err = fib_nl2rule(net, nlh, extack, ops, tb, rule: &nlrule, user_priority: &user_priority);
1033 if (err)
1034 goto errout;
1035
1036 if (!rtnl_held)
1037 rtnl_net_lock(net);
1038
1039 err = fib_nl2rule_rtnl(nlrule, ops, tb, extack);
1040 if (err)
1041 goto errout_free;
1042
1043 rule = rule_find(ops, frh, tb, rule: nlrule, user_priority);
1044 if (!rule) {
1045 err = -ENOENT;
1046 goto errout_free;
1047 }
1048
1049 if (rule->flags & FIB_RULE_PERMANENT) {
1050 err = -EPERM;
1051 goto errout_free;
1052 }
1053
1054 if (ops->delete) {
1055 err = ops->delete(rule);
1056 if (err)
1057 goto errout_free;
1058 }
1059
1060 if (rule->tun_id)
1061 ip_tunnel_unneed_metadata();
1062
1063 list_del_rcu(entry: &rule->list);
1064
1065 if (rule->action == FR_ACT_GOTO) {
1066 ops->nr_goto_rules--;
1067 if (rtnl_dereference(rule->ctarget) == NULL)
1068 ops->unresolved_rules--;
1069 }
1070
1071 /*
1072 * Check if this rule is a target to any of them. If so,
1073 * adjust to the next one with the same preference or
1074 * disable them. As this operation is eventually very
1075 * expensive, it is only performed if goto rules, except
1076 * current if it is goto rule, have actually been added.
1077 */
1078 if (ops->nr_goto_rules > 0) {
1079 struct fib_rule *n, *r;
1080
1081 n = list_next_entry(rule, list);
1082 if (&n->list == &ops->rules_list || n->pref != rule->pref)
1083 n = NULL;
1084 list_for_each_entry(r, &ops->rules_list, list) {
1085 if (rtnl_dereference(r->ctarget) != rule)
1086 continue;
1087 rcu_assign_pointer(r->ctarget, n);
1088 if (!n)
1089 ops->unresolved_rules++;
1090 }
1091 }
1092
1093 call_fib_rule_notifiers(net, event_type: FIB_EVENT_RULE_DEL, rule, ops, NULL);
1094
1095 if (!rtnl_held)
1096 rtnl_net_unlock(net);
1097
1098 notify_rule_change(RTM_DELRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
1099 fib_rule_put(rule);
1100 flush_route_cache(ops);
1101 rules_ops_put(ops);
1102 kfree(objp: nlrule);
1103 return 0;
1104
1105errout_free:
1106 if (!rtnl_held)
1107 rtnl_net_unlock(net);
1108 kfree(objp: nlrule);
1109errout:
1110 rules_ops_put(ops);
1111 return err;
1112}
1113EXPORT_SYMBOL_GPL(fib_delrule);
1114
1115static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
1116 struct netlink_ext_ack *extack)
1117{
1118 return fib_delrule(sock_net(sk: skb->sk), skb, nlh, extack, false);
1119}
1120
1121static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
1122 struct fib_rule *rule)
1123{
1124 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
1125 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
1126 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
1127 + nla_total_size(payload: 4) /* FRA_PRIORITY */
1128 + nla_total_size(payload: 4) /* FRA_TABLE */
1129 + nla_total_size(payload: 4) /* FRA_SUPPRESS_PREFIXLEN */
1130 + nla_total_size(payload: 4) /* FRA_SUPPRESS_IFGROUP */
1131 + nla_total_size(payload: 4) /* FRA_FWMARK */
1132 + nla_total_size(payload: 4) /* FRA_FWMASK */
1133 + nla_total_size_64bit(payload: 8) /* FRA_TUN_ID */
1134 + nla_total_size(payload: sizeof(struct fib_kuid_range))
1135 + nla_total_size(payload: 1) /* FRA_PROTOCOL */
1136 + nla_total_size(payload: 1) /* FRA_IP_PROTO */
1137 + nla_total_size(payload: sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */
1138 + nla_total_size(payload: sizeof(struct fib_rule_port_range)) /* FRA_DPORT_RANGE */
1139 + nla_total_size(payload: 2) /* FRA_SPORT_MASK */
1140 + nla_total_size(payload: 2); /* FRA_DPORT_MASK */
1141
1142 if (ops->nlmsg_payload)
1143 payload += ops->nlmsg_payload(rule);
1144
1145 return payload;
1146}
1147
1148static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
1149 u32 pid, u32 seq, int type, int flags,
1150 struct fib_rules_ops *ops)
1151{
1152 struct nlmsghdr *nlh;
1153 struct fib_rule_hdr *frh;
1154
1155 nlh = nlmsg_put(skb, portid: pid, seq, type, payload: sizeof(*frh), flags);
1156 if (nlh == NULL)
1157 return -EMSGSIZE;
1158
1159 frh = nlmsg_data(nlh);
1160 frh->family = ops->family;
1161 frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT;
1162 if (nla_put_u32(skb, attrtype: FRA_TABLE, value: rule->table))
1163 goto nla_put_failure;
1164 if (nla_put_u32(skb, attrtype: FRA_SUPPRESS_PREFIXLEN, value: rule->suppress_prefixlen))
1165 goto nla_put_failure;
1166 frh->res1 = 0;
1167 frh->res2 = 0;
1168 frh->action = rule->action;
1169 frh->flags = rule->flags;
1170
1171 if (nla_put_u8(skb, attrtype: FRA_PROTOCOL, value: rule->proto))
1172 goto nla_put_failure;
1173
1174 if (rule->action == FR_ACT_GOTO &&
1175 rcu_access_pointer(rule->ctarget) == NULL)
1176 frh->flags |= FIB_RULE_UNRESOLVED;
1177
1178 if (rule->iifname[0]) {
1179 if (nla_put_string(skb, attrtype: FRA_IIFNAME, str: rule->iifname))
1180 goto nla_put_failure;
1181 if (READ_ONCE(rule->iifindex) == -1)
1182 frh->flags |= FIB_RULE_IIF_DETACHED;
1183 }
1184
1185 if (rule->oifname[0]) {
1186 if (nla_put_string(skb, attrtype: FRA_OIFNAME, str: rule->oifname))
1187 goto nla_put_failure;
1188 if (READ_ONCE(rule->oifindex) == -1)
1189 frh->flags |= FIB_RULE_OIF_DETACHED;
1190 }
1191
1192 if ((rule->pref &&
1193 nla_put_u32(skb, attrtype: FRA_PRIORITY, value: rule->pref)) ||
1194 (rule->mark &&
1195 nla_put_u32(skb, attrtype: FRA_FWMARK, value: rule->mark)) ||
1196 ((rule->mark_mask || rule->mark) &&
1197 nla_put_u32(skb, attrtype: FRA_FWMASK, value: rule->mark_mask)) ||
1198 (rule->target &&
1199 nla_put_u32(skb, attrtype: FRA_GOTO, value: rule->target)) ||
1200 (rule->tun_id &&
1201 nla_put_be64(skb, attrtype: FRA_TUN_ID, value: rule->tun_id, padattr: FRA_PAD)) ||
1202 (rule->l3mdev &&
1203 nla_put_u8(skb, attrtype: FRA_L3MDEV, value: rule->l3mdev)) ||
1204 (uid_range_set(range: &rule->uid_range) &&
1205 nla_put_uid_range(skb, range: &rule->uid_range)) ||
1206 (fib_rule_port_range_set(range: &rule->sport_range) &&
1207 nla_put_port_range(skb, attrtype: FRA_SPORT_RANGE, range: &rule->sport_range)) ||
1208 (rule->sport_mask && nla_put_u16(skb, attrtype: FRA_SPORT_MASK,
1209 value: rule->sport_mask)) ||
1210 (fib_rule_port_range_set(range: &rule->dport_range) &&
1211 nla_put_port_range(skb, attrtype: FRA_DPORT_RANGE, range: &rule->dport_range)) ||
1212 (rule->dport_mask && nla_put_u16(skb, attrtype: FRA_DPORT_MASK,
1213 value: rule->dport_mask)) ||
1214 (rule->ip_proto && nla_put_u8(skb, attrtype: FRA_IP_PROTO, value: rule->ip_proto)))
1215 goto nla_put_failure;
1216
1217 if (rule->suppress_ifgroup != -1) {
1218 if (nla_put_u32(skb, attrtype: FRA_SUPPRESS_IFGROUP, value: rule->suppress_ifgroup))
1219 goto nla_put_failure;
1220 }
1221
1222 if (ops->fill(rule, skb, frh) < 0)
1223 goto nla_put_failure;
1224
1225 nlmsg_end(skb, nlh);
1226 return 0;
1227
1228nla_put_failure:
1229 nlmsg_cancel(skb, nlh);
1230 return -EMSGSIZE;
1231}
1232
1233static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
1234 struct fib_rules_ops *ops)
1235{
1236 int idx = 0;
1237 struct fib_rule *rule;
1238 int err = 0;
1239
1240 rcu_read_lock();
1241 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
1242 if (idx < cb->args[1])
1243 goto skip;
1244
1245 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
1246 seq: cb->nlh->nlmsg_seq, RTM_NEWRULE,
1247 NLM_F_MULTI, ops);
1248 if (err)
1249 break;
1250skip:
1251 idx++;
1252 }
1253 rcu_read_unlock();
1254 cb->args[1] = idx;
1255 rules_ops_put(ops);
1256
1257 return err;
1258}
1259
1260static int fib_valid_dumprule_req(const struct nlmsghdr *nlh,
1261 struct netlink_ext_ack *extack)
1262{
1263 struct fib_rule_hdr *frh;
1264
1265 frh = nlmsg_payload(nlh, len: sizeof(*frh));
1266 if (!frh) {
1267 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request");
1268 return -EINVAL;
1269 }
1270
1271 if (frh->dst_len || frh->src_len || frh->tos || frh->table ||
1272 frh->res1 || frh->res2 || frh->action || frh->flags) {
1273 NL_SET_ERR_MSG(extack,
1274 "Invalid values in header for fib rule dump request");
1275 return -EINVAL;
1276 }
1277
1278 if (nlmsg_attrlen(nlh, hdrlen: sizeof(*frh))) {
1279 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request");
1280 return -EINVAL;
1281 }
1282
1283 return 0;
1284}
1285
1286static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
1287{
1288 const struct nlmsghdr *nlh = cb->nlh;
1289 struct net *net = sock_net(sk: skb->sk);
1290 struct fib_rules_ops *ops;
1291 int err, idx = 0, family;
1292
1293 if (cb->strict_check) {
1294 err = fib_valid_dumprule_req(nlh, extack: cb->extack);
1295
1296 if (err < 0)
1297 return err;
1298 }
1299
1300 family = rtnl_msg_family(nlh);
1301 if (family != AF_UNSPEC) {
1302 /* Protocol specific dump request */
1303 ops = lookup_rules_ops(net, family);
1304 if (ops == NULL)
1305 return -EAFNOSUPPORT;
1306
1307 return dump_rules(skb, cb, ops);
1308 }
1309
1310 err = 0;
1311 rcu_read_lock();
1312 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
1313 if (idx < cb->args[0] || !try_module_get(module: ops->owner))
1314 goto skip;
1315
1316 err = dump_rules(skb, cb, ops);
1317 if (err < 0)
1318 break;
1319
1320 cb->args[1] = 0;
1321skip:
1322 idx++;
1323 }
1324 rcu_read_unlock();
1325 cb->args[0] = idx;
1326
1327 return err;
1328}
1329
1330static void notify_rule_change(int event, struct fib_rule *rule,
1331 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
1332 u32 pid)
1333{
1334 struct net *net;
1335 struct sk_buff *skb;
1336 int err = -ENOMEM;
1337
1338 net = ops->fro_net;
1339 skb = nlmsg_new(payload: fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
1340 if (skb == NULL)
1341 goto errout;
1342
1343 err = fib_nl_fill_rule(skb, rule, pid, seq: nlh->nlmsg_seq, type: event, flags: 0, ops);
1344 if (err < 0) {
1345 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
1346 WARN_ON(err == -EMSGSIZE);
1347 kfree_skb(skb);
1348 goto errout;
1349 }
1350
1351 rtnl_notify(skb, net, pid, group: ops->nlgroup, nlh, GFP_KERNEL);
1352 return;
1353errout:
1354 rtnl_set_sk_err(net, group: ops->nlgroup, error: err);
1355}
1356
1357static void attach_rules(struct list_head *rules, struct net_device *dev)
1358{
1359 struct fib_rule *rule;
1360
1361 list_for_each_entry(rule, rules, list) {
1362 if (rule->iifindex == -1 &&
1363 strcmp(dev->name, rule->iifname) == 0) {
1364 WRITE_ONCE(rule->iifindex, dev->ifindex);
1365 WRITE_ONCE(rule->iif_is_l3_master,
1366 netif_is_l3_master(dev));
1367 }
1368 if (rule->oifindex == -1 &&
1369 strcmp(dev->name, rule->oifname) == 0) {
1370 WRITE_ONCE(rule->oifindex, dev->ifindex);
1371 WRITE_ONCE(rule->oif_is_l3_master,
1372 netif_is_l3_master(dev));
1373 }
1374 }
1375}
1376
1377static void detach_rules(struct list_head *rules, struct net_device *dev)
1378{
1379 struct fib_rule *rule;
1380
1381 list_for_each_entry(rule, rules, list) {
1382 if (rule->iifindex == dev->ifindex) {
1383 WRITE_ONCE(rule->iifindex, -1);
1384 WRITE_ONCE(rule->iif_is_l3_master, false);
1385 }
1386 if (rule->oifindex == dev->ifindex) {
1387 WRITE_ONCE(rule->oifindex, -1);
1388 WRITE_ONCE(rule->oif_is_l3_master, false);
1389 }
1390 }
1391}
1392
1393
1394static int fib_rules_event(struct notifier_block *this, unsigned long event,
1395 void *ptr)
1396{
1397 struct net_device *dev = netdev_notifier_info_to_dev(info: ptr);
1398 struct net *net = dev_net(dev);
1399 struct fib_rules_ops *ops;
1400
1401 ASSERT_RTNL();
1402
1403 switch (event) {
1404 case NETDEV_REGISTER:
1405 list_for_each_entry(ops, &net->rules_ops, list)
1406 attach_rules(rules: &ops->rules_list, dev);
1407 break;
1408
1409 case NETDEV_CHANGENAME:
1410 list_for_each_entry(ops, &net->rules_ops, list) {
1411 detach_rules(rules: &ops->rules_list, dev);
1412 attach_rules(rules: &ops->rules_list, dev);
1413 }
1414 break;
1415
1416 case NETDEV_UNREGISTER:
1417 list_for_each_entry(ops, &net->rules_ops, list)
1418 detach_rules(rules: &ops->rules_list, dev);
1419 break;
1420 }
1421
1422 return NOTIFY_DONE;
1423}
1424
1425static struct notifier_block fib_rules_notifier = {
1426 .notifier_call = fib_rules_event,
1427};
1428
1429static int __net_init fib_rules_net_init(struct net *net)
1430{
1431 INIT_LIST_HEAD(list: &net->rules_ops);
1432 spin_lock_init(&net->rules_mod_lock);
1433 return 0;
1434}
1435
1436static void __net_exit fib_rules_net_exit(struct net *net)
1437{
1438 WARN_ON_ONCE(!list_empty(&net->rules_ops));
1439}
1440
1441static struct pernet_operations fib_rules_net_ops = {
1442 .init = fib_rules_net_init,
1443 .exit = fib_rules_net_exit,
1444};
1445
1446static const struct rtnl_msg_handler fib_rules_rtnl_msg_handlers[] __initconst = {
1447 {.msgtype = RTM_NEWRULE, .doit = fib_nl_newrule,
1448 .flags = RTNL_FLAG_DOIT_PERNET},
1449 {.msgtype = RTM_DELRULE, .doit = fib_nl_delrule,
1450 .flags = RTNL_FLAG_DOIT_PERNET},
1451 {.msgtype = RTM_GETRULE, .dumpit = fib_nl_dumprule,
1452 .flags = RTNL_FLAG_DUMP_UNLOCKED},
1453};
1454
1455static int __init fib_rules_init(void)
1456{
1457 int err;
1458
1459 rtnl_register_many(fib_rules_rtnl_msg_handlers);
1460
1461 err = register_pernet_subsys(&fib_rules_net_ops);
1462 if (err < 0)
1463 goto fail;
1464
1465 err = register_netdevice_notifier(nb: &fib_rules_notifier);
1466 if (err < 0)
1467 goto fail_unregister;
1468
1469 return 0;
1470
1471fail_unregister:
1472 unregister_pernet_subsys(&fib_rules_net_ops);
1473fail:
1474 rtnl_unregister_many(fib_rules_rtnl_msg_handlers);
1475 return err;
1476}
1477
1478subsys_initcall(fib_rules_init);
1479