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8#include <linux/nexthop.h>
9#include <linux/rtnetlink.h>
10#include <linux/slab.h>
11#include <net/arp.h>
12#include <net/ipv6_stubs.h>
13#include <net/lwtunnel.h>
14#include <net/ndisc.h>
15#include <net/nexthop.h>
16#include <net/route.h>
17#include <net/sock.h>
18
19static void remove_nexthop(struct net *net, struct nexthop *nh,
20 struct nl_info *nlinfo);
21
22#define NH_DEV_HASHBITS 8
23#define NH_DEV_HASHSIZE (1U << NH_DEV_HASHBITS)
24
25static const struct nla_policy rtm_nh_policy_new[] = {
26 [NHA_ID] = { .type = NLA_U32 },
27 [NHA_GROUP] = { .type = NLA_BINARY },
28 [NHA_GROUP_TYPE] = { .type = NLA_U16 },
29 [NHA_BLACKHOLE] = { .type = NLA_FLAG },
30 [NHA_OIF] = { .type = NLA_U32 },
31 [NHA_GATEWAY] = { .type = NLA_BINARY },
32 [NHA_ENCAP_TYPE] = { .type = NLA_U16 },
33 [NHA_ENCAP] = { .type = NLA_NESTED },
34 [NHA_FDB] = { .type = NLA_FLAG },
35};
36
37static const struct nla_policy rtm_nh_policy_get[] = {
38 [NHA_ID] = { .type = NLA_U32 },
39};
40
41static const struct nla_policy rtm_nh_policy_dump[] = {
42 [NHA_OIF] = { .type = NLA_U32 },
43 [NHA_GROUPS] = { .type = NLA_FLAG },
44 [NHA_MASTER] = { .type = NLA_U32 },
45 [NHA_FDB] = { .type = NLA_FLAG },
46};
47
48static bool nexthop_notifiers_is_empty(struct net *net)
49{
50 return !net->nexthop.notifier_chain.head;
51}
52
53static void
54__nh_notifier_single_info_init(struct nh_notifier_single_info *nh_info,
55 const struct nexthop *nh)
56{
57 struct nh_info *nhi = rtnl_dereference(nh->nh_info);
58
59 nh_info->dev = nhi->fib_nhc.nhc_dev;
60 nh_info->gw_family = nhi->fib_nhc.nhc_gw_family;
61 if (nh_info->gw_family == AF_INET)
62 nh_info->ipv4 = nhi->fib_nhc.nhc_gw.ipv4;
63 else if (nh_info->gw_family == AF_INET6)
64 nh_info->ipv6 = nhi->fib_nhc.nhc_gw.ipv6;
65
66 nh_info->is_reject = nhi->reject_nh;
67 nh_info->is_fdb = nhi->fdb_nh;
68 nh_info->has_encap = !!nhi->fib_nhc.nhc_lwtstate;
69}
70
71static int nh_notifier_single_info_init(struct nh_notifier_info *info,
72 const struct nexthop *nh)
73{
74 info->type = NH_NOTIFIER_INFO_TYPE_SINGLE;
75 info->nh = kzalloc(sizeof(*info->nh), GFP_KERNEL);
76 if (!info->nh)
77 return -ENOMEM;
78
79 __nh_notifier_single_info_init(info->nh, nh);
80
81 return 0;
82}
83
84static void nh_notifier_single_info_fini(struct nh_notifier_info *info)
85{
86 kfree(info->nh);
87}
88
89static int nh_notifier_mp_info_init(struct nh_notifier_info *info,
90 struct nh_group *nhg)
91{
92 u16 num_nh = nhg->num_nh;
93 int i;
94
95 info->type = NH_NOTIFIER_INFO_TYPE_GRP;
96 info->nh_grp = kzalloc(struct_size(info->nh_grp, nh_entries, num_nh),
97 GFP_KERNEL);
98 if (!info->nh_grp)
99 return -ENOMEM;
100
101 info->nh_grp->num_nh = num_nh;
102 info->nh_grp->is_fdb = nhg->fdb_nh;
103
104 for (i = 0; i < num_nh; i++) {
105 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
106
107 info->nh_grp->nh_entries[i].id = nhge->nh->id;
108 info->nh_grp->nh_entries[i].weight = nhge->weight;
109 __nh_notifier_single_info_init(&info->nh_grp->nh_entries[i].nh,
110 nhge->nh);
111 }
112
113 return 0;
114}
115
116static int nh_notifier_grp_info_init(struct nh_notifier_info *info,
117 const struct nexthop *nh)
118{
119 struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
120
121 if (nhg->mpath)
122 return nh_notifier_mp_info_init(info, nhg);
123 return -EINVAL;
124}
125
126static void nh_notifier_grp_info_fini(struct nh_notifier_info *info,
127 const struct nexthop *nh)
128{
129 struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
130
131 if (nhg->mpath)
132 kfree(info->nh_grp);
133}
134
135static int nh_notifier_info_init(struct nh_notifier_info *info,
136 const struct nexthop *nh)
137{
138 info->id = nh->id;
139
140 if (nh->is_group)
141 return nh_notifier_grp_info_init(info, nh);
142 else
143 return nh_notifier_single_info_init(info, nh);
144}
145
146static void nh_notifier_info_fini(struct nh_notifier_info *info,
147 const struct nexthop *nh)
148{
149 if (nh->is_group)
150 nh_notifier_grp_info_fini(info, nh);
151 else
152 nh_notifier_single_info_fini(info);
153}
154
155static int call_nexthop_notifiers(struct net *net,
156 enum nexthop_event_type event_type,
157 struct nexthop *nh,
158 struct netlink_ext_ack *extack)
159{
160 struct nh_notifier_info info = {
161 .net = net,
162 .extack = extack,
163 };
164 int err;
165
166 ASSERT_RTNL();
167
168 if (nexthop_notifiers_is_empty(net))
169 return 0;
170
171 err = nh_notifier_info_init(&info, nh);
172 if (err) {
173 NL_SET_ERR_MSG(extack, "Failed to initialize nexthop notifier info");
174 return err;
175 }
176
177 err = blocking_notifier_call_chain(&net->nexthop.notifier_chain,
178 event_type, &info);
179 nh_notifier_info_fini(&info, nh);
180
181 return notifier_to_errno(err);
182}
183
184static int call_nexthop_notifier(struct notifier_block *nb, struct net *net,
185 enum nexthop_event_type event_type,
186 struct nexthop *nh,
187 struct netlink_ext_ack *extack)
188{
189 struct nh_notifier_info info = {
190 .net = net,
191 .extack = extack,
192 };
193 int err;
194
195 err = nh_notifier_info_init(&info, nh);
196 if (err)
197 return err;
198
199 err = nb->notifier_call(nb, event_type, &info);
200 nh_notifier_info_fini(&info, nh);
201
202 return notifier_to_errno(err);
203}
204
205static unsigned int nh_dev_hashfn(unsigned int val)
206{
207 unsigned int mask = NH_DEV_HASHSIZE - 1;
208
209 return (val ^
210 (val >> NH_DEV_HASHBITS) ^
211 (val >> (NH_DEV_HASHBITS * 2))) & mask;
212}
213
214static void nexthop_devhash_add(struct net *net, struct nh_info *nhi)
215{
216 struct net_device *dev = nhi->fib_nhc.nhc_dev;
217 struct hlist_head *head;
218 unsigned int hash;
219
220 WARN_ON(!dev);
221
222 hash = nh_dev_hashfn(dev->ifindex);
223 head = &net->nexthop.devhash[hash];
224 hlist_add_head(&nhi->dev_hash, head);
225}
226
227static void nexthop_free_group(struct nexthop *nh)
228{
229 struct nh_group *nhg;
230 int i;
231
232 nhg = rcu_dereference_raw(nh->nh_grp);
233 for (i = 0; i < nhg->num_nh; ++i) {
234 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
235
236 WARN_ON(!list_empty(&nhge->nh_list));
237 nexthop_put(nhge->nh);
238 }
239
240 WARN_ON(nhg->spare == nhg);
241
242 kfree(nhg->spare);
243 kfree(nhg);
244}
245
246static void nexthop_free_single(struct nexthop *nh)
247{
248 struct nh_info *nhi;
249
250 nhi = rcu_dereference_raw(nh->nh_info);
251 switch (nhi->family) {
252 case AF_INET:
253 fib_nh_release(nh->net, &nhi->fib_nh);
254 break;
255 case AF_INET6:
256 ipv6_stub->fib6_nh_release(&nhi->fib6_nh);
257 break;
258 }
259 kfree(nhi);
260}
261
262void nexthop_free_rcu(struct rcu_head *head)
263{
264 struct nexthop *nh = container_of(head, struct nexthop, rcu);
265
266 if (nh->is_group)
267 nexthop_free_group(nh);
268 else
269 nexthop_free_single(nh);
270
271 kfree(nh);
272}
273EXPORT_SYMBOL_GPL(nexthop_free_rcu);
274
275static struct nexthop *nexthop_alloc(void)
276{
277 struct nexthop *nh;
278
279 nh = kzalloc(sizeof(struct nexthop), GFP_KERNEL);
280 if (nh) {
281 INIT_LIST_HEAD(&nh->fi_list);
282 INIT_LIST_HEAD(&nh->f6i_list);
283 INIT_LIST_HEAD(&nh->grp_list);
284 INIT_LIST_HEAD(&nh->fdb_list);
285 }
286 return nh;
287}
288
289static struct nh_group *nexthop_grp_alloc(u16 num_nh)
290{
291 struct nh_group *nhg;
292
293 nhg = kzalloc(struct_size(nhg, nh_entries, num_nh), GFP_KERNEL);
294 if (nhg)
295 nhg->num_nh = num_nh;
296
297 return nhg;
298}
299
300static void nh_base_seq_inc(struct net *net)
301{
302 while (++net->nexthop.seq == 0)
303 ;
304}
305
306
307struct nexthop *nexthop_find_by_id(struct net *net, u32 id)
308{
309 struct rb_node **pp, *parent = NULL, *next;
310
311 pp = &net->nexthop.rb_root.rb_node;
312 while (1) {
313 struct nexthop *nh;
314
315 next = rcu_dereference_raw(*pp);
316 if (!next)
317 break;
318 parent = next;
319
320 nh = rb_entry(parent, struct nexthop, rb_node);
321 if (id < nh->id)
322 pp = &next->rb_left;
323 else if (id > nh->id)
324 pp = &next->rb_right;
325 else
326 return nh;
327 }
328 return NULL;
329}
330EXPORT_SYMBOL_GPL(nexthop_find_by_id);
331
332
333static u32 nh_find_unused_id(struct net *net)
334{
335 u32 id_start = net->nexthop.last_id_allocated;
336
337 while (1) {
338 net->nexthop.last_id_allocated++;
339 if (net->nexthop.last_id_allocated == id_start)
340 break;
341
342 if (!nexthop_find_by_id(net, net->nexthop.last_id_allocated))
343 return net->nexthop.last_id_allocated;
344 }
345 return 0;
346}
347
348static int nla_put_nh_group(struct sk_buff *skb, struct nh_group *nhg)
349{
350 struct nexthop_grp *p;
351 size_t len = nhg->num_nh * sizeof(*p);
352 struct nlattr *nla;
353 u16 group_type = 0;
354 int i;
355
356 if (nhg->mpath)
357 group_type = NEXTHOP_GRP_TYPE_MPATH;
358
359 if (nla_put_u16(skb, NHA_GROUP_TYPE, group_type))
360 goto nla_put_failure;
361
362 nla = nla_reserve(skb, NHA_GROUP, len);
363 if (!nla)
364 goto nla_put_failure;
365
366 p = nla_data(nla);
367 for (i = 0; i < nhg->num_nh; ++i) {
368 p->id = nhg->nh_entries[i].nh->id;
369 p->weight = nhg->nh_entries[i].weight - 1;
370 p += 1;
371 }
372
373 return 0;
374
375nla_put_failure:
376 return -EMSGSIZE;
377}
378
379static int nh_fill_node(struct sk_buff *skb, struct nexthop *nh,
380 int event, u32 portid, u32 seq, unsigned int nlflags)
381{
382 struct fib6_nh *fib6_nh;
383 struct fib_nh *fib_nh;
384 struct nlmsghdr *nlh;
385 struct nh_info *nhi;
386 struct nhmsg *nhm;
387
388 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nhm), nlflags);
389 if (!nlh)
390 return -EMSGSIZE;
391
392 nhm = nlmsg_data(nlh);
393 nhm->nh_family = AF_UNSPEC;
394 nhm->nh_flags = nh->nh_flags;
395 nhm->nh_protocol = nh->protocol;
396 nhm->nh_scope = 0;
397 nhm->resvd = 0;
398
399 if (nla_put_u32(skb, NHA_ID, nh->id))
400 goto nla_put_failure;
401
402 if (nh->is_group) {
403 struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
404
405 if (nhg->fdb_nh && nla_put_flag(skb, NHA_FDB))
406 goto nla_put_failure;
407 if (nla_put_nh_group(skb, nhg))
408 goto nla_put_failure;
409 goto out;
410 }
411
412 nhi = rtnl_dereference(nh->nh_info);
413 nhm->nh_family = nhi->family;
414 if (nhi->reject_nh) {
415 if (nla_put_flag(skb, NHA_BLACKHOLE))
416 goto nla_put_failure;
417 goto out;
418 } else if (nhi->fdb_nh) {
419 if (nla_put_flag(skb, NHA_FDB))
420 goto nla_put_failure;
421 } else {
422 const struct net_device *dev;
423
424 dev = nhi->fib_nhc.nhc_dev;
425 if (dev && nla_put_u32(skb, NHA_OIF, dev->ifindex))
426 goto nla_put_failure;
427 }
428
429 nhm->nh_scope = nhi->fib_nhc.nhc_scope;
430 switch (nhi->family) {
431 case AF_INET:
432 fib_nh = &nhi->fib_nh;
433 if (fib_nh->fib_nh_gw_family &&
434 nla_put_be32(skb, NHA_GATEWAY, fib_nh->fib_nh_gw4))
435 goto nla_put_failure;
436 break;
437
438 case AF_INET6:
439 fib6_nh = &nhi->fib6_nh;
440 if (fib6_nh->fib_nh_gw_family &&
441 nla_put_in6_addr(skb, NHA_GATEWAY, &fib6_nh->fib_nh_gw6))
442 goto nla_put_failure;
443 break;
444 }
445
446 if (nhi->fib_nhc.nhc_lwtstate &&
447 lwtunnel_fill_encap(skb, nhi->fib_nhc.nhc_lwtstate,
448 NHA_ENCAP, NHA_ENCAP_TYPE) < 0)
449 goto nla_put_failure;
450
451out:
452 nlmsg_end(skb, nlh);
453 return 0;
454
455nla_put_failure:
456 nlmsg_cancel(skb, nlh);
457 return -EMSGSIZE;
458}
459
460static size_t nh_nlmsg_size_grp(struct nexthop *nh)
461{
462 struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
463 size_t sz = sizeof(struct nexthop_grp) * nhg->num_nh;
464
465 return nla_total_size(sz) +
466 nla_total_size(2);
467}
468
469static size_t nh_nlmsg_size_single(struct nexthop *nh)
470{
471 struct nh_info *nhi = rtnl_dereference(nh->nh_info);
472 size_t sz;
473
474
475
476
477 sz = nla_total_size(4);
478
479 switch (nhi->family) {
480 case AF_INET:
481 if (nhi->fib_nh.fib_nh_gw_family)
482 sz += nla_total_size(4);
483 break;
484
485 case AF_INET6:
486
487 if (nhi->fib6_nh.fib_nh_gw_family)
488 sz += nla_total_size(sizeof(const struct in6_addr));
489 break;
490 }
491
492 if (nhi->fib_nhc.nhc_lwtstate) {
493 sz += lwtunnel_get_encap_size(nhi->fib_nhc.nhc_lwtstate);
494 sz += nla_total_size(2);
495 }
496
497 return sz;
498}
499
500static size_t nh_nlmsg_size(struct nexthop *nh)
501{
502 size_t sz = NLMSG_ALIGN(sizeof(struct nhmsg));
503
504 sz += nla_total_size(4);
505
506 if (nh->is_group)
507 sz += nh_nlmsg_size_grp(nh);
508 else
509 sz += nh_nlmsg_size_single(nh);
510
511 return sz;
512}
513
514static void nexthop_notify(int event, struct nexthop *nh, struct nl_info *info)
515{
516 unsigned int nlflags = info->nlh ? info->nlh->nlmsg_flags : 0;
517 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
518 struct sk_buff *skb;
519 int err = -ENOBUFS;
520
521 skb = nlmsg_new(nh_nlmsg_size(nh), gfp_any());
522 if (!skb)
523 goto errout;
524
525 err = nh_fill_node(skb, nh, event, info->portid, seq, nlflags);
526 if (err < 0) {
527
528 WARN_ON(err == -EMSGSIZE);
529 kfree_skb(skb);
530 goto errout;
531 }
532
533 rtnl_notify(skb, info->nl_net, info->portid, RTNLGRP_NEXTHOP,
534 info->nlh, gfp_any());
535 return;
536errout:
537 if (err < 0)
538 rtnl_set_sk_err(info->nl_net, RTNLGRP_NEXTHOP, err);
539}
540
541static bool valid_group_nh(struct nexthop *nh, unsigned int npaths,
542 bool *is_fdb, struct netlink_ext_ack *extack)
543{
544 if (nh->is_group) {
545 struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
546
547
548
549
550 if (nhg->mpath) {
551 NL_SET_ERR_MSG(extack,
552 "Multipath group can not be a nexthop within a group");
553 return false;
554 }
555 *is_fdb = nhg->fdb_nh;
556 } else {
557 struct nh_info *nhi = rtnl_dereference(nh->nh_info);
558
559 if (nhi->reject_nh && npaths > 1) {
560 NL_SET_ERR_MSG(extack,
561 "Blackhole nexthop can not be used in a group with more than 1 path");
562 return false;
563 }
564 *is_fdb = nhi->fdb_nh;
565 }
566
567 return true;
568}
569
570static int nh_check_attr_fdb_group(struct nexthop *nh, u8 *nh_family,
571 struct netlink_ext_ack *extack)
572{
573 struct nh_info *nhi;
574
575 nhi = rtnl_dereference(nh->nh_info);
576
577 if (!nhi->fdb_nh) {
578 NL_SET_ERR_MSG(extack, "FDB nexthop group can only have fdb nexthops");
579 return -EINVAL;
580 }
581
582 if (*nh_family == AF_UNSPEC) {
583 *nh_family = nhi->family;
584 } else if (*nh_family != nhi->family) {
585 NL_SET_ERR_MSG(extack, "FDB nexthop group cannot have mixed family nexthops");
586 return -EINVAL;
587 }
588
589 return 0;
590}
591
592static int nh_check_attr_group(struct net *net,
593 struct nlattr *tb[], size_t tb_size,
594 struct netlink_ext_ack *extack)
595{
596 unsigned int len = nla_len(tb[NHA_GROUP]);
597 u8 nh_family = AF_UNSPEC;
598 struct nexthop_grp *nhg;
599 unsigned int i, j;
600 u8 nhg_fdb = 0;
601
602 if (!len || len & (sizeof(struct nexthop_grp) - 1)) {
603 NL_SET_ERR_MSG(extack,
604 "Invalid length for nexthop group attribute");
605 return -EINVAL;
606 }
607
608
609 len /= sizeof(*nhg);
610
611 nhg = nla_data(tb[NHA_GROUP]);
612 for (i = 0; i < len; ++i) {
613 if (nhg[i].resvd1 || nhg[i].resvd2) {
614 NL_SET_ERR_MSG(extack, "Reserved fields in nexthop_grp must be 0");
615 return -EINVAL;
616 }
617 if (nhg[i].weight > 254) {
618 NL_SET_ERR_MSG(extack, "Invalid value for weight");
619 return -EINVAL;
620 }
621 for (j = i + 1; j < len; ++j) {
622 if (nhg[i].id == nhg[j].id) {
623 NL_SET_ERR_MSG(extack, "Nexthop id can not be used twice in a group");
624 return -EINVAL;
625 }
626 }
627 }
628
629 if (tb[NHA_FDB])
630 nhg_fdb = 1;
631 nhg = nla_data(tb[NHA_GROUP]);
632 for (i = 0; i < len; ++i) {
633 struct nexthop *nh;
634 bool is_fdb_nh;
635
636 nh = nexthop_find_by_id(net, nhg[i].id);
637 if (!nh) {
638 NL_SET_ERR_MSG(extack, "Invalid nexthop id");
639 return -EINVAL;
640 }
641 if (!valid_group_nh(nh, len, &is_fdb_nh, extack))
642 return -EINVAL;
643
644 if (nhg_fdb && nh_check_attr_fdb_group(nh, &nh_family, extack))
645 return -EINVAL;
646
647 if (!nhg_fdb && is_fdb_nh) {
648 NL_SET_ERR_MSG(extack, "Non FDB nexthop group cannot have fdb nexthops");
649 return -EINVAL;
650 }
651 }
652 for (i = NHA_GROUP_TYPE + 1; i < tb_size; ++i) {
653 if (!tb[i])
654 continue;
655 if (i == NHA_FDB)
656 continue;
657 NL_SET_ERR_MSG(extack,
658 "No other attributes can be set in nexthop groups");
659 return -EINVAL;
660 }
661
662 return 0;
663}
664
665static bool ipv6_good_nh(const struct fib6_nh *nh)
666{
667 int state = NUD_REACHABLE;
668 struct neighbour *n;
669
670 rcu_read_lock_bh();
671
672 n = __ipv6_neigh_lookup_noref_stub(nh->fib_nh_dev, &nh->fib_nh_gw6);
673 if (n)
674 state = n->nud_state;
675
676 rcu_read_unlock_bh();
677
678 return !!(state & NUD_VALID);
679}
680
681static bool ipv4_good_nh(const struct fib_nh *nh)
682{
683 int state = NUD_REACHABLE;
684 struct neighbour *n;
685
686 rcu_read_lock_bh();
687
688 n = __ipv4_neigh_lookup_noref(nh->fib_nh_dev,
689 (__force u32)nh->fib_nh_gw4);
690 if (n)
691 state = n->nud_state;
692
693 rcu_read_unlock_bh();
694
695 return !!(state & NUD_VALID);
696}
697
698static struct nexthop *nexthop_select_path_mp(struct nh_group *nhg, int hash)
699{
700 struct nexthop *rc = NULL;
701 int i;
702
703 for (i = 0; i < nhg->num_nh; ++i) {
704 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
705 struct nh_info *nhi;
706
707 if (hash > atomic_read(&nhge->mpath.upper_bound))
708 continue;
709
710 nhi = rcu_dereference(nhge->nh->nh_info);
711 if (nhi->fdb_nh)
712 return nhge->nh;
713
714
715
716
717 switch (nhi->family) {
718 case AF_INET:
719 if (ipv4_good_nh(&nhi->fib_nh))
720 return nhge->nh;
721 break;
722 case AF_INET6:
723 if (ipv6_good_nh(&nhi->fib6_nh))
724 return nhge->nh;
725 break;
726 }
727
728 if (!rc)
729 rc = nhge->nh;
730 }
731
732 return rc;
733}
734
735struct nexthop *nexthop_select_path(struct nexthop *nh, int hash)
736{
737 struct nh_group *nhg;
738
739 if (!nh->is_group)
740 return nh;
741
742 nhg = rcu_dereference(nh->nh_grp);
743 if (nhg->mpath)
744 return nexthop_select_path_mp(nhg, hash);
745
746
747 return NULL;
748}
749EXPORT_SYMBOL_GPL(nexthop_select_path);
750
751int nexthop_for_each_fib6_nh(struct nexthop *nh,
752 int (*cb)(struct fib6_nh *nh, void *arg),
753 void *arg)
754{
755 struct nh_info *nhi;
756 int err;
757
758 if (nh->is_group) {
759 struct nh_group *nhg;
760 int i;
761
762 nhg = rcu_dereference_rtnl(nh->nh_grp);
763 for (i = 0; i < nhg->num_nh; i++) {
764 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
765
766 nhi = rcu_dereference_rtnl(nhge->nh->nh_info);
767 err = cb(&nhi->fib6_nh, arg);
768 if (err)
769 return err;
770 }
771 } else {
772 nhi = rcu_dereference_rtnl(nh->nh_info);
773 err = cb(&nhi->fib6_nh, arg);
774 if (err)
775 return err;
776 }
777
778 return 0;
779}
780EXPORT_SYMBOL_GPL(nexthop_for_each_fib6_nh);
781
782static int check_src_addr(const struct in6_addr *saddr,
783 struct netlink_ext_ack *extack)
784{
785 if (!ipv6_addr_any(saddr)) {
786 NL_SET_ERR_MSG(extack, "IPv6 routes using source address can not use nexthop objects");
787 return -EINVAL;
788 }
789 return 0;
790}
791
792int fib6_check_nexthop(struct nexthop *nh, struct fib6_config *cfg,
793 struct netlink_ext_ack *extack)
794{
795 struct nh_info *nhi;
796 bool is_fdb_nh;
797
798
799
800
801
802
803
804 if (cfg && check_src_addr(&cfg->fc_src, extack) < 0)
805 return -EINVAL;
806
807 if (nh->is_group) {
808 struct nh_group *nhg;
809
810 nhg = rtnl_dereference(nh->nh_grp);
811 if (nhg->has_v4)
812 goto no_v4_nh;
813 is_fdb_nh = nhg->fdb_nh;
814 } else {
815 nhi = rtnl_dereference(nh->nh_info);
816 if (nhi->family == AF_INET)
817 goto no_v4_nh;
818 is_fdb_nh = nhi->fdb_nh;
819 }
820
821 if (is_fdb_nh) {
822 NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop");
823 return -EINVAL;
824 }
825
826 return 0;
827no_v4_nh:
828 NL_SET_ERR_MSG(extack, "IPv6 routes can not use an IPv4 nexthop");
829 return -EINVAL;
830}
831EXPORT_SYMBOL_GPL(fib6_check_nexthop);
832
833
834
835
836static int fib6_check_nh_list(struct nexthop *old, struct nexthop *new,
837 struct netlink_ext_ack *extack)
838{
839 struct fib6_info *f6i;
840
841 if (list_empty(&old->f6i_list))
842 return 0;
843
844 list_for_each_entry(f6i, &old->f6i_list, nh_list) {
845 if (check_src_addr(&f6i->fib6_src.addr, extack) < 0)
846 return -EINVAL;
847 }
848
849 return fib6_check_nexthop(new, NULL, extack);
850}
851
852static int nexthop_check_scope(struct nh_info *nhi, u8 scope,
853 struct netlink_ext_ack *extack)
854{
855 if (scope == RT_SCOPE_HOST && nhi->fib_nhc.nhc_gw_family) {
856 NL_SET_ERR_MSG(extack,
857 "Route with host scope can not have a gateway");
858 return -EINVAL;
859 }
860
861 if (nhi->fib_nhc.nhc_flags & RTNH_F_ONLINK && scope >= RT_SCOPE_LINK) {
862 NL_SET_ERR_MSG(extack, "Scope mismatch with nexthop");
863 return -EINVAL;
864 }
865
866 return 0;
867}
868
869
870
871
872
873int fib_check_nexthop(struct nexthop *nh, u8 scope,
874 struct netlink_ext_ack *extack)
875{
876 struct nh_info *nhi;
877 int err = 0;
878
879 if (nh->is_group) {
880 struct nh_group *nhg;
881
882 nhg = rtnl_dereference(nh->nh_grp);
883 if (nhg->fdb_nh) {
884 NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop");
885 err = -EINVAL;
886 goto out;
887 }
888
889 if (scope == RT_SCOPE_HOST) {
890 NL_SET_ERR_MSG(extack, "Route with host scope can not have multiple nexthops");
891 err = -EINVAL;
892 goto out;
893 }
894
895
896 nhi = rtnl_dereference(nhg->nh_entries[0].nh->nh_info);
897 err = nexthop_check_scope(nhi, scope, extack);
898 } else {
899 nhi = rtnl_dereference(nh->nh_info);
900 if (nhi->fdb_nh) {
901 NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop");
902 err = -EINVAL;
903 goto out;
904 }
905 err = nexthop_check_scope(nhi, scope, extack);
906 }
907
908out:
909 return err;
910}
911
912static int fib_check_nh_list(struct nexthop *old, struct nexthop *new,
913 struct netlink_ext_ack *extack)
914{
915 struct fib_info *fi;
916
917 list_for_each_entry(fi, &old->fi_list, nh_list) {
918 int err;
919
920 err = fib_check_nexthop(new, fi->fib_scope, extack);
921 if (err)
922 return err;
923 }
924 return 0;
925}
926
927static void nh_group_rebalance(struct nh_group *nhg)
928{
929 int total = 0;
930 int w = 0;
931 int i;
932
933 for (i = 0; i < nhg->num_nh; ++i)
934 total += nhg->nh_entries[i].weight;
935
936 for (i = 0; i < nhg->num_nh; ++i) {
937 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
938 int upper_bound;
939
940 w += nhge->weight;
941 upper_bound = DIV_ROUND_CLOSEST_ULL((u64)w << 31, total) - 1;
942 atomic_set(&nhge->mpath.upper_bound, upper_bound);
943 }
944}
945
946static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge,
947 struct nl_info *nlinfo)
948{
949 struct nh_grp_entry *nhges, *new_nhges;
950 struct nexthop *nhp = nhge->nh_parent;
951 struct netlink_ext_ack extack;
952 struct nexthop *nh = nhge->nh;
953 struct nh_group *nhg, *newg;
954 int i, j, err;
955
956 WARN_ON(!nh);
957
958 nhg = rtnl_dereference(nhp->nh_grp);
959 newg = nhg->spare;
960
961
962 if (nhg->num_nh == 1) {
963 remove_nexthop(net, nhp, nlinfo);
964 return;
965 }
966
967 newg->has_v4 = false;
968 newg->mpath = nhg->mpath;
969 newg->fdb_nh = nhg->fdb_nh;
970 newg->num_nh = nhg->num_nh;
971
972
973 nhges = nhg->nh_entries;
974 new_nhges = newg->nh_entries;
975 for (i = 0, j = 0; i < nhg->num_nh; ++i) {
976 struct nh_info *nhi;
977
978
979 if (nhg->nh_entries[i].nh == nh) {
980 newg->num_nh--;
981 continue;
982 }
983
984 nhi = rtnl_dereference(nhges[i].nh->nh_info);
985 if (nhi->family == AF_INET)
986 newg->has_v4 = true;
987
988 list_del(&nhges[i].nh_list);
989 new_nhges[j].nh_parent = nhges[i].nh_parent;
990 new_nhges[j].nh = nhges[i].nh;
991 new_nhges[j].weight = nhges[i].weight;
992 list_add(&new_nhges[j].nh_list, &new_nhges[j].nh->grp_list);
993 j++;
994 }
995
996 nh_group_rebalance(newg);
997 rcu_assign_pointer(nhp->nh_grp, newg);
998
999 list_del(&nhge->nh_list);
1000 nexthop_put(nhge->nh);
1001
1002 err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp, &extack);
1003 if (err)
1004 pr_err("%s\n", extack._msg);
1005
1006 if (nlinfo)
1007 nexthop_notify(RTM_NEWNEXTHOP, nhp, nlinfo);
1008}
1009
1010static void remove_nexthop_from_groups(struct net *net, struct nexthop *nh,
1011 struct nl_info *nlinfo)
1012{
1013 struct nh_grp_entry *nhge, *tmp;
1014
1015 list_for_each_entry_safe(nhge, tmp, &nh->grp_list, nh_list)
1016 remove_nh_grp_entry(net, nhge, nlinfo);
1017
1018
1019 synchronize_net();
1020}
1021
1022static void remove_nexthop_group(struct nexthop *nh, struct nl_info *nlinfo)
1023{
1024 struct nh_group *nhg = rcu_dereference_rtnl(nh->nh_grp);
1025 int i, num_nh = nhg->num_nh;
1026
1027 for (i = 0; i < num_nh; ++i) {
1028 struct nh_grp_entry *nhge = &nhg->nh_entries[i];
1029
1030 if (WARN_ON(!nhge->nh))
1031 continue;
1032
1033 list_del_init(&nhge->nh_list);
1034 }
1035}
1036
1037
1038static void __remove_nexthop_fib(struct net *net, struct nexthop *nh)
1039{
1040 struct fib6_info *f6i, *tmp;
1041 bool do_flush = false;
1042 struct fib_info *fi;
1043
1044 list_for_each_entry(fi, &nh->fi_list, nh_list) {
1045 fi->fib_flags |= RTNH_F_DEAD;
1046 do_flush = true;
1047 }
1048 if (do_flush)
1049 fib_flush(net);
1050
1051
1052 list_for_each_entry_safe(f6i, tmp, &nh->f6i_list, nh_list) {
1053
1054 fib6_info_hold(f6i);
1055 ipv6_stub->ip6_del_rt(net, f6i,
1056 !net->ipv4.sysctl_nexthop_compat_mode);
1057 }
1058}
1059
1060static void __remove_nexthop(struct net *net, struct nexthop *nh,
1061 struct nl_info *nlinfo)
1062{
1063 __remove_nexthop_fib(net, nh);
1064
1065 if (nh->is_group) {
1066 remove_nexthop_group(nh, nlinfo);
1067 } else {
1068 struct nh_info *nhi;
1069
1070 nhi = rtnl_dereference(nh->nh_info);
1071 if (nhi->fib_nhc.nhc_dev)
1072 hlist_del(&nhi->dev_hash);
1073
1074 remove_nexthop_from_groups(net, nh, nlinfo);
1075 }
1076}
1077
1078static void remove_nexthop(struct net *net, struct nexthop *nh,
1079 struct nl_info *nlinfo)
1080{
1081 call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh, NULL);
1082
1083
1084 rb_erase(&nh->rb_node, &net->nexthop.rb_root);
1085
1086 if (nlinfo)
1087 nexthop_notify(RTM_DELNEXTHOP, nh, nlinfo);
1088
1089 __remove_nexthop(net, nh, nlinfo);
1090 nh_base_seq_inc(net);
1091
1092 nexthop_put(nh);
1093}
1094
1095
1096
1097
1098static void nh_rt_cache_flush(struct net *net, struct nexthop *nh)
1099{
1100 struct fib6_info *f6i;
1101
1102 if (!list_empty(&nh->fi_list))
1103 rt_cache_flush(net);
1104
1105 list_for_each_entry(f6i, &nh->f6i_list, nh_list)
1106 ipv6_stub->fib6_update_sernum(net, f6i);
1107}
1108
1109static int replace_nexthop_grp(struct net *net, struct nexthop *old,
1110 struct nexthop *new,
1111 struct netlink_ext_ack *extack)
1112{
1113 struct nh_group *oldg, *newg;
1114 int i, err;
1115
1116 if (!new->is_group) {
1117 NL_SET_ERR_MSG(extack, "Can not replace a nexthop group with a nexthop.");
1118 return -EINVAL;
1119 }
1120
1121 err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack);
1122 if (err)
1123 return err;
1124
1125 oldg = rtnl_dereference(old->nh_grp);
1126 newg = rtnl_dereference(new->nh_grp);
1127
1128
1129 for (i = 0; i < newg->num_nh; i++)
1130 newg->nh_entries[i].nh_parent = old;
1131
1132 rcu_assign_pointer(old->nh_grp, newg);
1133
1134 for (i = 0; i < oldg->num_nh; i++)
1135 oldg->nh_entries[i].nh_parent = new;
1136
1137 rcu_assign_pointer(new->nh_grp, oldg);
1138
1139 return 0;
1140}
1141
1142static void nh_group_v4_update(struct nh_group *nhg)
1143{
1144 struct nh_grp_entry *nhges;
1145 bool has_v4 = false;
1146 int i;
1147
1148 nhges = nhg->nh_entries;
1149 for (i = 0; i < nhg->num_nh; i++) {
1150 struct nh_info *nhi;
1151
1152 nhi = rtnl_dereference(nhges[i].nh->nh_info);
1153 if (nhi->family == AF_INET)
1154 has_v4 = true;
1155 }
1156 nhg->has_v4 = has_v4;
1157}
1158
1159static int replace_nexthop_single(struct net *net, struct nexthop *old,
1160 struct nexthop *new,
1161 struct netlink_ext_ack *extack)
1162{
1163 u8 old_protocol, old_nh_flags;
1164 struct nh_info *oldi, *newi;
1165 struct nh_grp_entry *nhge;
1166 int err;
1167
1168 if (new->is_group) {
1169 NL_SET_ERR_MSG(extack, "Can not replace a nexthop with a nexthop group.");
1170 return -EINVAL;
1171 }
1172
1173 err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack);
1174 if (err)
1175 return err;
1176
1177
1178
1179
1180 new->nh_flags |= old->nh_flags & (RTNH_F_OFFLOAD | RTNH_F_TRAP);
1181
1182 oldi = rtnl_dereference(old->nh_info);
1183 newi = rtnl_dereference(new->nh_info);
1184
1185 newi->nh_parent = old;
1186 oldi->nh_parent = new;
1187
1188 old_protocol = old->protocol;
1189 old_nh_flags = old->nh_flags;
1190
1191 old->protocol = new->protocol;
1192 old->nh_flags = new->nh_flags;
1193
1194 rcu_assign_pointer(old->nh_info, newi);
1195 rcu_assign_pointer(new->nh_info, oldi);
1196
1197
1198 list_for_each_entry(nhge, &old->grp_list, nh_list) {
1199 struct nexthop *nhp = nhge->nh_parent;
1200
1201 err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp,
1202 extack);
1203 if (err)
1204 goto err_notify;
1205 }
1206
1207
1208
1209
1210 if (oldi->family == AF_INET && newi->family == AF_INET6) {
1211 list_for_each_entry(nhge, &old->grp_list, nh_list) {
1212 struct nexthop *nhp = nhge->nh_parent;
1213 struct nh_group *nhg;
1214
1215 nhg = rtnl_dereference(nhp->nh_grp);
1216 nh_group_v4_update(nhg);
1217 }
1218 }
1219
1220 return 0;
1221
1222err_notify:
1223 rcu_assign_pointer(new->nh_info, newi);
1224 rcu_assign_pointer(old->nh_info, oldi);
1225 old->nh_flags = old_nh_flags;
1226 old->protocol = old_protocol;
1227 oldi->nh_parent = old;
1228 newi->nh_parent = new;
1229 list_for_each_entry_continue_reverse(nhge, &old->grp_list, nh_list) {
1230 struct nexthop *nhp = nhge->nh_parent;
1231
1232 call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp, extack);
1233 }
1234 call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, old, extack);
1235 return err;
1236}
1237
1238static void __nexthop_replace_notify(struct net *net, struct nexthop *nh,
1239 struct nl_info *info)
1240{
1241 struct fib6_info *f6i;
1242
1243 if (!list_empty(&nh->fi_list)) {
1244 struct fib_info *fi;
1245
1246
1247
1248
1249
1250 list_for_each_entry(fi, &nh->fi_list, nh_list)
1251 fi->nh_updated = true;
1252
1253 fib_info_notify_update(net, info);
1254
1255 list_for_each_entry(fi, &nh->fi_list, nh_list)
1256 fi->nh_updated = false;
1257 }
1258
1259 list_for_each_entry(f6i, &nh->f6i_list, nh_list)
1260 ipv6_stub->fib6_rt_update(net, f6i, info);
1261}
1262
1263
1264
1265
1266
1267static void nexthop_replace_notify(struct net *net, struct nexthop *nh,
1268 struct nl_info *info)
1269{
1270 struct nh_grp_entry *nhge;
1271
1272 __nexthop_replace_notify(net, nh, info);
1273
1274 list_for_each_entry(nhge, &nh->grp_list, nh_list)
1275 __nexthop_replace_notify(net, nhge->nh_parent, info);
1276}
1277
1278static int replace_nexthop(struct net *net, struct nexthop *old,
1279 struct nexthop *new, struct netlink_ext_ack *extack)
1280{
1281 bool new_is_reject = false;
1282 struct nh_grp_entry *nhge;
1283 int err;
1284
1285
1286
1287
1288 err = fib_check_nh_list(old, new, extack);
1289 if (err)
1290 return err;
1291
1292 err = fib6_check_nh_list(old, new, extack);
1293 if (err)
1294 return err;
1295
1296 if (!new->is_group) {
1297 struct nh_info *nhi = rtnl_dereference(new->nh_info);
1298
1299 new_is_reject = nhi->reject_nh;
1300 }
1301
1302 list_for_each_entry(nhge, &old->grp_list, nh_list) {
1303
1304
1305
1306 if (new_is_reject &&
1307 nexthop_num_path(nhge->nh_parent) > 1) {
1308 NL_SET_ERR_MSG(extack, "Blackhole nexthop can not be a member of a group with more than one path");
1309 return -EINVAL;
1310 }
1311
1312 err = fib_check_nh_list(nhge->nh_parent, new, extack);
1313 if (err)
1314 return err;
1315
1316 err = fib6_check_nh_list(nhge->nh_parent, new, extack);
1317 if (err)
1318 return err;
1319 }
1320
1321 if (old->is_group)
1322 err = replace_nexthop_grp(net, old, new, extack);
1323 else
1324 err = replace_nexthop_single(net, old, new, extack);
1325
1326 if (!err) {
1327 nh_rt_cache_flush(net, old);
1328
1329 __remove_nexthop(net, new, NULL);
1330 nexthop_put(new);
1331 }
1332
1333 return err;
1334}
1335
1336
1337static int insert_nexthop(struct net *net, struct nexthop *new_nh,
1338 struct nh_config *cfg, struct netlink_ext_ack *extack)
1339{
1340 struct rb_node **pp, *parent = NULL, *next;
1341 struct rb_root *root = &net->nexthop.rb_root;
1342 bool replace = !!(cfg->nlflags & NLM_F_REPLACE);
1343 bool create = !!(cfg->nlflags & NLM_F_CREATE);
1344 u32 new_id = new_nh->id;
1345 int replace_notify = 0;
1346 int rc = -EEXIST;
1347
1348 pp = &root->rb_node;
1349 while (1) {
1350 struct nexthop *nh;
1351
1352 next = *pp;
1353 if (!next)
1354 break;
1355
1356 parent = next;
1357
1358 nh = rb_entry(parent, struct nexthop, rb_node);
1359 if (new_id < nh->id) {
1360 pp = &next->rb_left;
1361 } else if (new_id > nh->id) {
1362 pp = &next->rb_right;
1363 } else if (replace) {
1364 rc = replace_nexthop(net, nh, new_nh, extack);
1365 if (!rc) {
1366 new_nh = nh;
1367 replace_notify = 1;
1368 }
1369 goto out;
1370 } else {
1371
1372 goto out;
1373 }
1374 }
1375
1376 if (replace && !create) {
1377 NL_SET_ERR_MSG(extack, "Replace specified without create and no entry exists");
1378 rc = -ENOENT;
1379 goto out;
1380 }
1381
1382 rb_link_node_rcu(&new_nh->rb_node, parent, pp);
1383 rb_insert_color(&new_nh->rb_node, root);
1384
1385 rc = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new_nh, extack);
1386 if (rc)
1387 rb_erase(&new_nh->rb_node, &net->nexthop.rb_root);
1388
1389out:
1390 if (!rc) {
1391 nh_base_seq_inc(net);
1392 nexthop_notify(RTM_NEWNEXTHOP, new_nh, &cfg->nlinfo);
1393 if (replace_notify && net->ipv4.sysctl_nexthop_compat_mode)
1394 nexthop_replace_notify(net, new_nh, &cfg->nlinfo);
1395 }
1396
1397 return rc;
1398}
1399
1400
1401
1402static void nexthop_flush_dev(struct net_device *dev, unsigned long event)
1403{
1404 unsigned int hash = nh_dev_hashfn(dev->ifindex);
1405 struct net *net = dev_net(dev);
1406 struct hlist_head *head = &net->nexthop.devhash[hash];
1407 struct hlist_node *n;
1408 struct nh_info *nhi;
1409
1410 hlist_for_each_entry_safe(nhi, n, head, dev_hash) {
1411 if (nhi->fib_nhc.nhc_dev != dev)
1412 continue;
1413
1414 if (nhi->reject_nh &&
1415 (event == NETDEV_DOWN || event == NETDEV_CHANGE))
1416 continue;
1417
1418 remove_nexthop(net, nhi->nh_parent, NULL);
1419 }
1420}
1421
1422
1423static void flush_all_nexthops(struct net *net)
1424{
1425 struct rb_root *root = &net->nexthop.rb_root;
1426 struct rb_node *node;
1427 struct nexthop *nh;
1428
1429 while ((node = rb_first(root))) {
1430 nh = rb_entry(node, struct nexthop, rb_node);
1431 remove_nexthop(net, nh, NULL);
1432 cond_resched();
1433 }
1434}
1435
1436static struct nexthop *nexthop_create_group(struct net *net,
1437 struct nh_config *cfg)
1438{
1439 struct nlattr *grps_attr = cfg->nh_grp;
1440 struct nexthop_grp *entry = nla_data(grps_attr);
1441 u16 num_nh = nla_len(grps_attr) / sizeof(*entry);
1442 struct nh_group *nhg;
1443 struct nexthop *nh;
1444 int i;
1445
1446 if (WARN_ON(!num_nh))
1447 return ERR_PTR(-EINVAL);
1448
1449 nh = nexthop_alloc();
1450 if (!nh)
1451 return ERR_PTR(-ENOMEM);
1452
1453 nh->is_group = 1;
1454
1455 nhg = nexthop_grp_alloc(num_nh);
1456 if (!nhg) {
1457 kfree(nh);
1458 return ERR_PTR(-ENOMEM);
1459 }
1460
1461
1462 nhg->spare = nexthop_grp_alloc(num_nh);
1463 if (!nhg->spare) {
1464 kfree(nhg);
1465 kfree(nh);
1466 return ERR_PTR(-ENOMEM);
1467 }
1468 nhg->spare->spare = nhg;
1469
1470 for (i = 0; i < nhg->num_nh; ++i) {
1471 struct nexthop *nhe;
1472 struct nh_info *nhi;
1473
1474 nhe = nexthop_find_by_id(net, entry[i].id);
1475 if (!nexthop_get(nhe))
1476 goto out_no_nh;
1477
1478 nhi = rtnl_dereference(nhe->nh_info);
1479 if (nhi->family == AF_INET)
1480 nhg->has_v4 = true;
1481
1482 nhg->nh_entries[i].nh = nhe;
1483 nhg->nh_entries[i].weight = entry[i].weight + 1;
1484 list_add(&nhg->nh_entries[i].nh_list, &nhe->grp_list);
1485 nhg->nh_entries[i].nh_parent = nh;
1486 }
1487
1488 if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_MPATH)
1489 nhg->mpath = 1;
1490
1491 WARN_ON_ONCE(nhg->mpath != 1);
1492
1493 if (nhg->mpath)
1494 nh_group_rebalance(nhg);
1495
1496 if (cfg->nh_fdb)
1497 nhg->fdb_nh = 1;
1498
1499 rcu_assign_pointer(nh->nh_grp, nhg);
1500
1501 return nh;
1502
1503out_no_nh:
1504 for (i--; i >= 0; --i) {
1505 list_del(&nhg->nh_entries[i].nh_list);
1506 nexthop_put(nhg->nh_entries[i].nh);
1507 }
1508
1509 kfree(nhg->spare);
1510 kfree(nhg);
1511 kfree(nh);
1512
1513 return ERR_PTR(-ENOENT);
1514}
1515
1516static int nh_create_ipv4(struct net *net, struct nexthop *nh,
1517 struct nh_info *nhi, struct nh_config *cfg,
1518 struct netlink_ext_ack *extack)
1519{
1520 struct fib_nh *fib_nh = &nhi->fib_nh;
1521 struct fib_config fib_cfg = {
1522 .fc_oif = cfg->nh_ifindex,
1523 .fc_gw4 = cfg->gw.ipv4,
1524 .fc_gw_family = cfg->gw.ipv4 ? AF_INET : 0,
1525 .fc_flags = cfg->nh_flags,
1526 .fc_encap = cfg->nh_encap,
1527 .fc_encap_type = cfg->nh_encap_type,
1528 };
1529 u32 tb_id = (cfg->dev ? l3mdev_fib_table(cfg->dev) : RT_TABLE_MAIN);
1530 int err;
1531
1532 err = fib_nh_init(net, fib_nh, &fib_cfg, 1, extack);
1533 if (err) {
1534 fib_nh_release(net, fib_nh);
1535 goto out;
1536 }
1537
1538 if (nhi->fdb_nh)
1539 goto out;
1540
1541
1542 err = fib_check_nh(net, fib_nh, tb_id, 0, extack);
1543 if (!err) {
1544 nh->nh_flags = fib_nh->fib_nh_flags;
1545 fib_info_update_nhc_saddr(net, &fib_nh->nh_common,
1546 fib_nh->fib_nh_scope);
1547 } else {
1548 fib_nh_release(net, fib_nh);
1549 }
1550out:
1551 return err;
1552}
1553
1554static int nh_create_ipv6(struct net *net, struct nexthop *nh,
1555 struct nh_info *nhi, struct nh_config *cfg,
1556 struct netlink_ext_ack *extack)
1557{
1558 struct fib6_nh *fib6_nh = &nhi->fib6_nh;
1559 struct fib6_config fib6_cfg = {
1560 .fc_table = l3mdev_fib_table(cfg->dev),
1561 .fc_ifindex = cfg->nh_ifindex,
1562 .fc_gateway = cfg->gw.ipv6,
1563 .fc_flags = cfg->nh_flags,
1564 .fc_encap = cfg->nh_encap,
1565 .fc_encap_type = cfg->nh_encap_type,
1566 .fc_is_fdb = cfg->nh_fdb,
1567 };
1568 int err;
1569
1570 if (!ipv6_addr_any(&cfg->gw.ipv6))
1571 fib6_cfg.fc_flags |= RTF_GATEWAY;
1572
1573
1574 err = ipv6_stub->fib6_nh_init(net, fib6_nh, &fib6_cfg, GFP_KERNEL,
1575 extack);
1576 if (err)
1577 ipv6_stub->fib6_nh_release(fib6_nh);
1578 else
1579 nh->nh_flags = fib6_nh->fib_nh_flags;
1580
1581 return err;
1582}
1583
1584static struct nexthop *nexthop_create(struct net *net, struct nh_config *cfg,
1585 struct netlink_ext_ack *extack)
1586{
1587 struct nh_info *nhi;
1588 struct nexthop *nh;
1589 int err = 0;
1590
1591 nh = nexthop_alloc();
1592 if (!nh)
1593 return ERR_PTR(-ENOMEM);
1594
1595 nhi = kzalloc(sizeof(*nhi), GFP_KERNEL);
1596 if (!nhi) {
1597 kfree(nh);
1598 return ERR_PTR(-ENOMEM);
1599 }
1600
1601 nh->nh_flags = cfg->nh_flags;
1602 nh->net = net;
1603
1604 nhi->nh_parent = nh;
1605 nhi->family = cfg->nh_family;
1606 nhi->fib_nhc.nhc_scope = RT_SCOPE_LINK;
1607
1608 if (cfg->nh_fdb)
1609 nhi->fdb_nh = 1;
1610
1611 if (cfg->nh_blackhole) {
1612 nhi->reject_nh = 1;
1613 cfg->nh_ifindex = net->loopback_dev->ifindex;
1614 }
1615
1616 switch (cfg->nh_family) {
1617 case AF_INET:
1618 err = nh_create_ipv4(net, nh, nhi, cfg, extack);
1619 break;
1620 case AF_INET6:
1621 err = nh_create_ipv6(net, nh, nhi, cfg, extack);
1622 break;
1623 }
1624
1625 if (err) {
1626 kfree(nhi);
1627 kfree(nh);
1628 return ERR_PTR(err);
1629 }
1630
1631
1632 if (!nhi->fdb_nh)
1633 nexthop_devhash_add(net, nhi);
1634
1635 rcu_assign_pointer(nh->nh_info, nhi);
1636
1637 return nh;
1638}
1639
1640
1641static struct nexthop *nexthop_add(struct net *net, struct nh_config *cfg,
1642 struct netlink_ext_ack *extack)
1643{
1644 struct nexthop *nh;
1645 int err;
1646
1647 if (cfg->nlflags & NLM_F_REPLACE && !cfg->nh_id) {
1648 NL_SET_ERR_MSG(extack, "Replace requires nexthop id");
1649 return ERR_PTR(-EINVAL);
1650 }
1651
1652 if (!cfg->nh_id) {
1653 cfg->nh_id = nh_find_unused_id(net);
1654 if (!cfg->nh_id) {
1655 NL_SET_ERR_MSG(extack, "No unused id");
1656 return ERR_PTR(-EINVAL);
1657 }
1658 }
1659
1660 if (cfg->nh_grp)
1661 nh = nexthop_create_group(net, cfg);
1662 else
1663 nh = nexthop_create(net, cfg, extack);
1664
1665 if (IS_ERR(nh))
1666 return nh;
1667
1668 refcount_set(&nh->refcnt, 1);
1669 nh->id = cfg->nh_id;
1670 nh->protocol = cfg->nh_protocol;
1671 nh->net = net;
1672
1673 err = insert_nexthop(net, nh, cfg, extack);
1674 if (err) {
1675 __remove_nexthop(net, nh, NULL);
1676 nexthop_put(nh);
1677 nh = ERR_PTR(err);
1678 }
1679
1680 return nh;
1681}
1682
1683static int rtm_to_nh_config(struct net *net, struct sk_buff *skb,
1684 struct nlmsghdr *nlh, struct nh_config *cfg,
1685 struct netlink_ext_ack *extack)
1686{
1687 struct nhmsg *nhm = nlmsg_data(nlh);
1688 struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_new)];
1689 int err;
1690
1691 err = nlmsg_parse(nlh, sizeof(*nhm), tb,
1692 ARRAY_SIZE(rtm_nh_policy_new) - 1,
1693 rtm_nh_policy_new, extack);
1694 if (err < 0)
1695 return err;
1696
1697 err = -EINVAL;
1698 if (nhm->resvd || nhm->nh_scope) {
1699 NL_SET_ERR_MSG(extack, "Invalid values in ancillary header");
1700 goto out;
1701 }
1702 if (nhm->nh_flags & ~NEXTHOP_VALID_USER_FLAGS) {
1703 NL_SET_ERR_MSG(extack, "Invalid nexthop flags in ancillary header");
1704 goto out;
1705 }
1706
1707 switch (nhm->nh_family) {
1708 case AF_INET:
1709 case AF_INET6:
1710 break;
1711 case AF_UNSPEC:
1712 if (tb[NHA_GROUP])
1713 break;
1714 fallthrough;
1715 default:
1716 NL_SET_ERR_MSG(extack, "Invalid address family");
1717 goto out;
1718 }
1719
1720 memset(cfg, 0, sizeof(*cfg));
1721 cfg->nlflags = nlh->nlmsg_flags;
1722 cfg->nlinfo.portid = NETLINK_CB(skb).portid;
1723 cfg->nlinfo.nlh = nlh;
1724 cfg->nlinfo.nl_net = net;
1725
1726 cfg->nh_family = nhm->nh_family;
1727 cfg->nh_protocol = nhm->nh_protocol;
1728 cfg->nh_flags = nhm->nh_flags;
1729
1730 if (tb[NHA_ID])
1731 cfg->nh_id = nla_get_u32(tb[NHA_ID]);
1732
1733 if (tb[NHA_FDB]) {
1734 if (tb[NHA_OIF] || tb[NHA_BLACKHOLE] ||
1735 tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE]) {
1736 NL_SET_ERR_MSG(extack, "Fdb attribute can not be used with encap, oif or blackhole");
1737 goto out;
1738 }
1739 if (nhm->nh_flags) {
1740 NL_SET_ERR_MSG(extack, "Unsupported nexthop flags in ancillary header");
1741 goto out;
1742 }
1743 cfg->nh_fdb = nla_get_flag(tb[NHA_FDB]);
1744 }
1745
1746 if (tb[NHA_GROUP]) {
1747 if (nhm->nh_family != AF_UNSPEC) {
1748 NL_SET_ERR_MSG(extack, "Invalid family for group");
1749 goto out;
1750 }
1751 cfg->nh_grp = tb[NHA_GROUP];
1752
1753 cfg->nh_grp_type = NEXTHOP_GRP_TYPE_MPATH;
1754 if (tb[NHA_GROUP_TYPE])
1755 cfg->nh_grp_type = nla_get_u16(tb[NHA_GROUP_TYPE]);
1756
1757 if (cfg->nh_grp_type > NEXTHOP_GRP_TYPE_MAX) {
1758 NL_SET_ERR_MSG(extack, "Invalid group type");
1759 goto out;
1760 }
1761 err = nh_check_attr_group(net, tb, ARRAY_SIZE(tb), extack);
1762
1763
1764 goto out;
1765 }
1766
1767 if (tb[NHA_BLACKHOLE]) {
1768 if (tb[NHA_GATEWAY] || tb[NHA_OIF] ||
1769 tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE] || tb[NHA_FDB]) {
1770 NL_SET_ERR_MSG(extack, "Blackhole attribute can not be used with gateway, oif, encap or fdb");
1771 goto out;
1772 }
1773
1774 cfg->nh_blackhole = 1;
1775 err = 0;
1776 goto out;
1777 }
1778
1779 if (!cfg->nh_fdb && !tb[NHA_OIF]) {
1780 NL_SET_ERR_MSG(extack, "Device attribute required for non-blackhole and non-fdb nexthops");
1781 goto out;
1782 }
1783
1784 if (!cfg->nh_fdb && tb[NHA_OIF]) {
1785 cfg->nh_ifindex = nla_get_u32(tb[NHA_OIF]);
1786 if (cfg->nh_ifindex)
1787 cfg->dev = __dev_get_by_index(net, cfg->nh_ifindex);
1788
1789 if (!cfg->dev) {
1790 NL_SET_ERR_MSG(extack, "Invalid device index");
1791 goto out;
1792 } else if (!(cfg->dev->flags & IFF_UP)) {
1793 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
1794 err = -ENETDOWN;
1795 goto out;
1796 } else if (!netif_carrier_ok(cfg->dev)) {
1797 NL_SET_ERR_MSG(extack, "Carrier for nexthop device is down");
1798 err = -ENETDOWN;
1799 goto out;
1800 }
1801 }
1802
1803 err = -EINVAL;
1804 if (tb[NHA_GATEWAY]) {
1805 struct nlattr *gwa = tb[NHA_GATEWAY];
1806
1807 switch (cfg->nh_family) {
1808 case AF_INET:
1809 if (nla_len(gwa) != sizeof(u32)) {
1810 NL_SET_ERR_MSG(extack, "Invalid gateway");
1811 goto out;
1812 }
1813 cfg->gw.ipv4 = nla_get_be32(gwa);
1814 break;
1815 case AF_INET6:
1816 if (nla_len(gwa) != sizeof(struct in6_addr)) {
1817 NL_SET_ERR_MSG(extack, "Invalid gateway");
1818 goto out;
1819 }
1820 cfg->gw.ipv6 = nla_get_in6_addr(gwa);
1821 break;
1822 default:
1823 NL_SET_ERR_MSG(extack,
1824 "Unknown address family for gateway");
1825 goto out;
1826 }
1827 } else {
1828
1829 if (cfg->nh_flags & RTNH_F_ONLINK) {
1830 NL_SET_ERR_MSG(extack,
1831 "ONLINK flag can not be set for nexthop without a gateway");
1832 goto out;
1833 }
1834 }
1835
1836 if (tb[NHA_ENCAP]) {
1837 cfg->nh_encap = tb[NHA_ENCAP];
1838
1839 if (!tb[NHA_ENCAP_TYPE]) {
1840 NL_SET_ERR_MSG(extack, "LWT encapsulation type is missing");
1841 goto out;
1842 }
1843
1844 cfg->nh_encap_type = nla_get_u16(tb[NHA_ENCAP_TYPE]);
1845 err = lwtunnel_valid_encap_type(cfg->nh_encap_type, extack);
1846 if (err < 0)
1847 goto out;
1848
1849 } else if (tb[NHA_ENCAP_TYPE]) {
1850 NL_SET_ERR_MSG(extack, "LWT encapsulation attribute is missing");
1851 goto out;
1852 }
1853
1854
1855 err = 0;
1856out:
1857 return err;
1858}
1859
1860
1861static int rtm_new_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh,
1862 struct netlink_ext_ack *extack)
1863{
1864 struct net *net = sock_net(skb->sk);
1865 struct nh_config cfg;
1866 struct nexthop *nh;
1867 int err;
1868
1869 err = rtm_to_nh_config(net, skb, nlh, &cfg, extack);
1870 if (!err) {
1871 nh = nexthop_add(net, &cfg, extack);
1872 if (IS_ERR(nh))
1873 err = PTR_ERR(nh);
1874 }
1875
1876 return err;
1877}
1878
1879static int __nh_valid_get_del_req(const struct nlmsghdr *nlh,
1880 struct nlattr **tb, u32 *id,
1881 struct netlink_ext_ack *extack)
1882{
1883 struct nhmsg *nhm = nlmsg_data(nlh);
1884
1885 if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) {
1886 NL_SET_ERR_MSG(extack, "Invalid values in header");
1887 return -EINVAL;
1888 }
1889
1890 if (!tb[NHA_ID]) {
1891 NL_SET_ERR_MSG(extack, "Nexthop id is missing");
1892 return -EINVAL;
1893 }
1894
1895 *id = nla_get_u32(tb[NHA_ID]);
1896 if (!(*id)) {
1897 NL_SET_ERR_MSG(extack, "Invalid nexthop id");
1898 return -EINVAL;
1899 }
1900
1901 return 0;
1902}
1903
1904static int nh_valid_get_del_req(const struct nlmsghdr *nlh, u32 *id,
1905 struct netlink_ext_ack *extack)
1906{
1907 struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get)];
1908 int err;
1909
1910 err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb,
1911 ARRAY_SIZE(rtm_nh_policy_get) - 1,
1912 rtm_nh_policy_get, extack);
1913 if (err < 0)
1914 return err;
1915
1916 return __nh_valid_get_del_req(nlh, tb, id, extack);
1917}
1918
1919
1920static int rtm_del_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh,
1921 struct netlink_ext_ack *extack)
1922{
1923 struct net *net = sock_net(skb->sk);
1924 struct nl_info nlinfo = {
1925 .nlh = nlh,
1926 .nl_net = net,
1927 .portid = NETLINK_CB(skb).portid,
1928 };
1929 struct nexthop *nh;
1930 int err;
1931 u32 id;
1932
1933 err = nh_valid_get_del_req(nlh, &id, extack);
1934 if (err)
1935 return err;
1936
1937 nh = nexthop_find_by_id(net, id);
1938 if (!nh)
1939 return -ENOENT;
1940
1941 remove_nexthop(net, nh, &nlinfo);
1942
1943 return 0;
1944}
1945
1946
1947static int rtm_get_nexthop(struct sk_buff *in_skb, struct nlmsghdr *nlh,
1948 struct netlink_ext_ack *extack)
1949{
1950 struct net *net = sock_net(in_skb->sk);
1951 struct sk_buff *skb = NULL;
1952 struct nexthop *nh;
1953 int err;
1954 u32 id;
1955
1956 err = nh_valid_get_del_req(nlh, &id, extack);
1957 if (err)
1958 return err;
1959
1960 err = -ENOBUFS;
1961 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1962 if (!skb)
1963 goto out;
1964
1965 err = -ENOENT;
1966 nh = nexthop_find_by_id(net, id);
1967 if (!nh)
1968 goto errout_free;
1969
1970 err = nh_fill_node(skb, nh, RTM_NEWNEXTHOP, NETLINK_CB(in_skb).portid,
1971 nlh->nlmsg_seq, 0);
1972 if (err < 0) {
1973 WARN_ON(err == -EMSGSIZE);
1974 goto errout_free;
1975 }
1976
1977 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1978out:
1979 return err;
1980errout_free:
1981 kfree_skb(skb);
1982 goto out;
1983}
1984
1985struct nh_dump_filter {
1986 int dev_idx;
1987 int master_idx;
1988 bool group_filter;
1989 bool fdb_filter;
1990};
1991
1992static bool nh_dump_filtered(struct nexthop *nh,
1993 struct nh_dump_filter *filter, u8 family)
1994{
1995 const struct net_device *dev;
1996 const struct nh_info *nhi;
1997
1998 if (filter->group_filter && !nh->is_group)
1999 return true;
2000
2001 if (!filter->dev_idx && !filter->master_idx && !family)
2002 return false;
2003
2004 if (nh->is_group)
2005 return true;
2006
2007 nhi = rtnl_dereference(nh->nh_info);
2008 if (family && nhi->family != family)
2009 return true;
2010
2011 dev = nhi->fib_nhc.nhc_dev;
2012 if (filter->dev_idx && (!dev || dev->ifindex != filter->dev_idx))
2013 return true;
2014
2015 if (filter->master_idx) {
2016 struct net_device *master;
2017
2018 if (!dev)
2019 return true;
2020
2021 master = netdev_master_upper_dev_get((struct net_device *)dev);
2022 if (!master || master->ifindex != filter->master_idx)
2023 return true;
2024 }
2025
2026 return false;
2027}
2028
2029static int __nh_valid_dump_req(const struct nlmsghdr *nlh, struct nlattr **tb,
2030 struct nh_dump_filter *filter,
2031 struct netlink_ext_ack *extack)
2032{
2033 struct nhmsg *nhm;
2034 u32 idx;
2035
2036 if (tb[NHA_OIF]) {
2037 idx = nla_get_u32(tb[NHA_OIF]);
2038 if (idx > INT_MAX) {
2039 NL_SET_ERR_MSG(extack, "Invalid device index");
2040 return -EINVAL;
2041 }
2042 filter->dev_idx = idx;
2043 }
2044 if (tb[NHA_MASTER]) {
2045 idx = nla_get_u32(tb[NHA_MASTER]);
2046 if (idx > INT_MAX) {
2047 NL_SET_ERR_MSG(extack, "Invalid master device index");
2048 return -EINVAL;
2049 }
2050 filter->master_idx = idx;
2051 }
2052 filter->group_filter = nla_get_flag(tb[NHA_GROUPS]);
2053 filter->fdb_filter = nla_get_flag(tb[NHA_FDB]);
2054
2055 nhm = nlmsg_data(nlh);
2056 if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) {
2057 NL_SET_ERR_MSG(extack, "Invalid values in header for nexthop dump request");
2058 return -EINVAL;
2059 }
2060
2061 return 0;
2062}
2063
2064static int nh_valid_dump_req(const struct nlmsghdr *nlh,
2065 struct nh_dump_filter *filter,
2066 struct netlink_callback *cb)
2067{
2068 struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_dump)];
2069 int err;
2070
2071 err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb,
2072 ARRAY_SIZE(rtm_nh_policy_dump) - 1,
2073 rtm_nh_policy_dump, cb->extack);
2074 if (err < 0)
2075 return err;
2076
2077 return __nh_valid_dump_req(nlh, tb, filter, cb->extack);
2078}
2079
2080struct rtm_dump_nh_ctx {
2081 u32 idx;
2082};
2083
2084static struct rtm_dump_nh_ctx *
2085rtm_dump_nh_ctx(struct netlink_callback *cb)
2086{
2087 struct rtm_dump_nh_ctx *ctx = (void *)cb->ctx;
2088
2089 BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
2090 return ctx;
2091}
2092
2093static int rtm_dump_walk_nexthops(struct sk_buff *skb,
2094 struct netlink_callback *cb,
2095 struct rb_root *root,
2096 struct rtm_dump_nh_ctx *ctx,
2097 int (*nh_cb)(struct sk_buff *skb,
2098 struct netlink_callback *cb,
2099 struct nexthop *nh, void *data),
2100 void *data)
2101{
2102 struct rb_node *node;
2103 int idx = 0, s_idx;
2104 int err;
2105
2106 s_idx = ctx->idx;
2107 for (node = rb_first(root); node; node = rb_next(node)) {
2108 struct nexthop *nh;
2109
2110 if (idx < s_idx)
2111 goto cont;
2112
2113 nh = rb_entry(node, struct nexthop, rb_node);
2114 ctx->idx = idx;
2115 err = nh_cb(skb, cb, nh, data);
2116 if (err)
2117 return err;
2118cont:
2119 idx++;
2120 }
2121
2122 ctx->idx = idx;
2123 return 0;
2124}
2125
2126static int rtm_dump_nexthop_cb(struct sk_buff *skb, struct netlink_callback *cb,
2127 struct nexthop *nh, void *data)
2128{
2129 struct nhmsg *nhm = nlmsg_data(cb->nlh);
2130 struct nh_dump_filter *filter = data;
2131
2132 if (nh_dump_filtered(nh, filter, nhm->nh_family))
2133 return 0;
2134
2135 return nh_fill_node(skb, nh, RTM_NEWNEXTHOP,
2136 NETLINK_CB(cb->skb).portid,
2137 cb->nlh->nlmsg_seq, NLM_F_MULTI);
2138}
2139
2140
2141static int rtm_dump_nexthop(struct sk_buff *skb, struct netlink_callback *cb)
2142{
2143 struct rtm_dump_nh_ctx *ctx = rtm_dump_nh_ctx(cb);
2144 struct net *net = sock_net(skb->sk);
2145 struct rb_root *root = &net->nexthop.rb_root;
2146 struct nh_dump_filter filter = {};
2147 int err;
2148
2149 err = nh_valid_dump_req(cb->nlh, &filter, cb);
2150 if (err < 0)
2151 return err;
2152
2153 err = rtm_dump_walk_nexthops(skb, cb, root, ctx,
2154 &rtm_dump_nexthop_cb, &filter);
2155 if (err < 0) {
2156 if (likely(skb->len))
2157 goto out;
2158 goto out_err;
2159 }
2160
2161out:
2162 err = skb->len;
2163out_err:
2164 cb->seq = net->nexthop.seq;
2165 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
2166 return err;
2167}
2168
2169static void nexthop_sync_mtu(struct net_device *dev, u32 orig_mtu)
2170{
2171 unsigned int hash = nh_dev_hashfn(dev->ifindex);
2172 struct net *net = dev_net(dev);
2173 struct hlist_head *head = &net->nexthop.devhash[hash];
2174 struct hlist_node *n;
2175 struct nh_info *nhi;
2176
2177 hlist_for_each_entry_safe(nhi, n, head, dev_hash) {
2178 if (nhi->fib_nhc.nhc_dev == dev) {
2179 if (nhi->family == AF_INET)
2180 fib_nhc_update_mtu(&nhi->fib_nhc, dev->mtu,
2181 orig_mtu);
2182 }
2183 }
2184}
2185
2186
2187static int nh_netdev_event(struct notifier_block *this,
2188 unsigned long event, void *ptr)
2189{
2190 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2191 struct netdev_notifier_info_ext *info_ext;
2192
2193 switch (event) {
2194 case NETDEV_DOWN:
2195 case NETDEV_UNREGISTER:
2196 nexthop_flush_dev(dev, event);
2197 break;
2198 case NETDEV_CHANGE:
2199 if (!(dev_get_flags(dev) & (IFF_RUNNING | IFF_LOWER_UP)))
2200 nexthop_flush_dev(dev, event);
2201 break;
2202 case NETDEV_CHANGEMTU:
2203 info_ext = ptr;
2204 nexthop_sync_mtu(dev, info_ext->ext.mtu);
2205 rt_cache_flush(dev_net(dev));
2206 break;
2207 }
2208 return NOTIFY_DONE;
2209}
2210
2211static struct notifier_block nh_netdev_notifier = {
2212 .notifier_call = nh_netdev_event,
2213};
2214
2215static int nexthops_dump(struct net *net, struct notifier_block *nb,
2216 struct netlink_ext_ack *extack)
2217{
2218 struct rb_root *root = &net->nexthop.rb_root;
2219 struct rb_node *node;
2220 int err = 0;
2221
2222 for (node = rb_first(root); node; node = rb_next(node)) {
2223 struct nexthop *nh;
2224
2225 nh = rb_entry(node, struct nexthop, rb_node);
2226 err = call_nexthop_notifier(nb, net, NEXTHOP_EVENT_REPLACE, nh,
2227 extack);
2228 if (err)
2229 break;
2230 }
2231
2232 return err;
2233}
2234
2235int register_nexthop_notifier(struct net *net, struct notifier_block *nb,
2236 struct netlink_ext_ack *extack)
2237{
2238 int err;
2239
2240 rtnl_lock();
2241 err = nexthops_dump(net, nb, extack);
2242 if (err)
2243 goto unlock;
2244 err = blocking_notifier_chain_register(&net->nexthop.notifier_chain,
2245 nb);
2246unlock:
2247 rtnl_unlock();
2248 return err;
2249}
2250EXPORT_SYMBOL(register_nexthop_notifier);
2251
2252int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb)
2253{
2254 return blocking_notifier_chain_unregister(&net->nexthop.notifier_chain,
2255 nb);
2256}
2257EXPORT_SYMBOL(unregister_nexthop_notifier);
2258
2259void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap)
2260{
2261 struct nexthop *nexthop;
2262
2263 rcu_read_lock();
2264
2265 nexthop = nexthop_find_by_id(net, id);
2266 if (!nexthop)
2267 goto out;
2268
2269 nexthop->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP);
2270 if (offload)
2271 nexthop->nh_flags |= RTNH_F_OFFLOAD;
2272 if (trap)
2273 nexthop->nh_flags |= RTNH_F_TRAP;
2274
2275out:
2276 rcu_read_unlock();
2277}
2278EXPORT_SYMBOL(nexthop_set_hw_flags);
2279
2280static void __net_exit nexthop_net_exit(struct net *net)
2281{
2282 rtnl_lock();
2283 flush_all_nexthops(net);
2284 rtnl_unlock();
2285 kfree(net->nexthop.devhash);
2286}
2287
2288static int __net_init nexthop_net_init(struct net *net)
2289{
2290 size_t sz = sizeof(struct hlist_head) * NH_DEV_HASHSIZE;
2291
2292 net->nexthop.rb_root = RB_ROOT;
2293 net->nexthop.devhash = kzalloc(sz, GFP_KERNEL);
2294 if (!net->nexthop.devhash)
2295 return -ENOMEM;
2296 BLOCKING_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain);
2297
2298 return 0;
2299}
2300
2301static struct pernet_operations nexthop_net_ops = {
2302 .init = nexthop_net_init,
2303 .exit = nexthop_net_exit,
2304};
2305
2306static int __init nexthop_init(void)
2307{
2308 register_pernet_subsys(&nexthop_net_ops);
2309
2310 register_netdevice_notifier(&nh_netdev_notifier);
2311
2312 rtnl_register(PF_UNSPEC, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0);
2313 rtnl_register(PF_UNSPEC, RTM_DELNEXTHOP, rtm_del_nexthop, NULL, 0);
2314 rtnl_register(PF_UNSPEC, RTM_GETNEXTHOP, rtm_get_nexthop,
2315 rtm_dump_nexthop, 0);
2316
2317 rtnl_register(PF_INET, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0);
2318 rtnl_register(PF_INET, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0);
2319
2320 rtnl_register(PF_INET6, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0);
2321 rtnl_register(PF_INET6, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0);
2322
2323 return 0;
2324}
2325subsys_initcall(nexthop_init);
2326
