dccp: fix use-after-free in dccp_feat_activate_values
[linux/fpc-iii.git] / net / ipv6 / route.c
blob7ea85370c11c81e8743e6a3086a32a0011f35d17
1 /*
2 * Linux INET6 implementation
3 * FIB front-end.
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
14 /* Changes:
16 * YOSHIFUJI Hideaki @USAGI
17 * reworked default router selection.
18 * - respect outgoing interface
19 * - select from (probably) reachable routers (i.e.
20 * routers in REACHABLE, STALE, DELAY or PROBE states).
21 * - always select the same router if it is (probably)
22 * reachable. otherwise, round-robin the list.
23 * Ville Nuorvala
24 * Fixed routing subtrees.
27 #define pr_fmt(fmt) "IPv6: " fmt
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/export.h>
32 #include <linux/types.h>
33 #include <linux/times.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <linux/net.h>
37 #include <linux/route.h>
38 #include <linux/netdevice.h>
39 #include <linux/in6.h>
40 #include <linux/mroute6.h>
41 #include <linux/init.h>
42 #include <linux/if_arp.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/nsproxy.h>
46 #include <linux/slab.h>
47 #include <net/net_namespace.h>
48 #include <net/snmp.h>
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ndisc.h>
53 #include <net/addrconf.h>
54 #include <net/tcp.h>
55 #include <linux/rtnetlink.h>
56 #include <net/dst.h>
57 #include <net/dst_metadata.h>
58 #include <net/xfrm.h>
59 #include <net/netevent.h>
60 #include <net/netlink.h>
61 #include <net/nexthop.h>
62 #include <net/lwtunnel.h>
63 #include <net/ip_tunnels.h>
64 #include <net/l3mdev.h>
65 #include <trace/events/fib6.h>
67 #include <linux/uaccess.h>
69 #ifdef CONFIG_SYSCTL
70 #include <linux/sysctl.h>
71 #endif
73 enum rt6_nud_state {
74 RT6_NUD_FAIL_HARD = -3,
75 RT6_NUD_FAIL_PROBE = -2,
76 RT6_NUD_FAIL_DO_RR = -1,
77 RT6_NUD_SUCCEED = 1
80 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
81 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
82 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
83 static unsigned int ip6_mtu(const struct dst_entry *dst);
84 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
85 static void ip6_dst_destroy(struct dst_entry *);
86 static void ip6_dst_ifdown(struct dst_entry *,
87 struct net_device *dev, int how);
88 static int ip6_dst_gc(struct dst_ops *ops);
90 static int ip6_pkt_discard(struct sk_buff *skb);
91 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
92 static int ip6_pkt_prohibit(struct sk_buff *skb);
93 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
94 static void ip6_link_failure(struct sk_buff *skb);
95 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
96 struct sk_buff *skb, u32 mtu);
97 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
98 struct sk_buff *skb);
99 static void rt6_dst_from_metrics_check(struct rt6_info *rt);
100 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
102 #ifdef CONFIG_IPV6_ROUTE_INFO
103 static struct rt6_info *rt6_add_route_info(struct net *net,
104 const struct in6_addr *prefix, int prefixlen,
105 const struct in6_addr *gwaddr,
106 struct net_device *dev,
107 unsigned int pref);
108 static struct rt6_info *rt6_get_route_info(struct net *net,
109 const struct in6_addr *prefix, int prefixlen,
110 const struct in6_addr *gwaddr,
111 struct net_device *dev);
112 #endif
114 struct uncached_list {
115 spinlock_t lock;
116 struct list_head head;
119 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
121 static void rt6_uncached_list_add(struct rt6_info *rt)
123 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
125 rt->dst.flags |= DST_NOCACHE;
126 rt->rt6i_uncached_list = ul;
128 spin_lock_bh(&ul->lock);
129 list_add_tail(&rt->rt6i_uncached, &ul->head);
130 spin_unlock_bh(&ul->lock);
133 static void rt6_uncached_list_del(struct rt6_info *rt)
135 if (!list_empty(&rt->rt6i_uncached)) {
136 struct uncached_list *ul = rt->rt6i_uncached_list;
138 spin_lock_bh(&ul->lock);
139 list_del(&rt->rt6i_uncached);
140 spin_unlock_bh(&ul->lock);
144 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
146 struct net_device *loopback_dev = net->loopback_dev;
147 int cpu;
149 if (dev == loopback_dev)
150 return;
152 for_each_possible_cpu(cpu) {
153 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
154 struct rt6_info *rt;
156 spin_lock_bh(&ul->lock);
157 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
158 struct inet6_dev *rt_idev = rt->rt6i_idev;
159 struct net_device *rt_dev = rt->dst.dev;
161 if (rt_idev->dev == dev) {
162 rt->rt6i_idev = in6_dev_get(loopback_dev);
163 in6_dev_put(rt_idev);
166 if (rt_dev == dev) {
167 rt->dst.dev = loopback_dev;
168 dev_hold(rt->dst.dev);
169 dev_put(rt_dev);
172 spin_unlock_bh(&ul->lock);
176 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
178 return dst_metrics_write_ptr(rt->dst.from);
181 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
183 struct rt6_info *rt = (struct rt6_info *)dst;
185 if (rt->rt6i_flags & RTF_PCPU)
186 return rt6_pcpu_cow_metrics(rt);
187 else if (rt->rt6i_flags & RTF_CACHE)
188 return NULL;
189 else
190 return dst_cow_metrics_generic(dst, old);
193 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
194 struct sk_buff *skb,
195 const void *daddr)
197 struct in6_addr *p = &rt->rt6i_gateway;
199 if (!ipv6_addr_any(p))
200 return (const void *) p;
201 else if (skb)
202 return &ipv6_hdr(skb)->daddr;
203 return daddr;
206 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
207 struct sk_buff *skb,
208 const void *daddr)
210 struct rt6_info *rt = (struct rt6_info *) dst;
211 struct neighbour *n;
213 daddr = choose_neigh_daddr(rt, skb, daddr);
214 n = __ipv6_neigh_lookup(dst->dev, daddr);
215 if (n)
216 return n;
217 return neigh_create(&nd_tbl, daddr, dst->dev);
220 static struct dst_ops ip6_dst_ops_template = {
221 .family = AF_INET6,
222 .gc = ip6_dst_gc,
223 .gc_thresh = 1024,
224 .check = ip6_dst_check,
225 .default_advmss = ip6_default_advmss,
226 .mtu = ip6_mtu,
227 .cow_metrics = ipv6_cow_metrics,
228 .destroy = ip6_dst_destroy,
229 .ifdown = ip6_dst_ifdown,
230 .negative_advice = ip6_negative_advice,
231 .link_failure = ip6_link_failure,
232 .update_pmtu = ip6_rt_update_pmtu,
233 .redirect = rt6_do_redirect,
234 .local_out = __ip6_local_out,
235 .neigh_lookup = ip6_neigh_lookup,
238 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
240 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
242 return mtu ? : dst->dev->mtu;
245 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
246 struct sk_buff *skb, u32 mtu)
250 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
251 struct sk_buff *skb)
255 static struct dst_ops ip6_dst_blackhole_ops = {
256 .family = AF_INET6,
257 .destroy = ip6_dst_destroy,
258 .check = ip6_dst_check,
259 .mtu = ip6_blackhole_mtu,
260 .default_advmss = ip6_default_advmss,
261 .update_pmtu = ip6_rt_blackhole_update_pmtu,
262 .redirect = ip6_rt_blackhole_redirect,
263 .cow_metrics = dst_cow_metrics_generic,
264 .neigh_lookup = ip6_neigh_lookup,
267 static const u32 ip6_template_metrics[RTAX_MAX] = {
268 [RTAX_HOPLIMIT - 1] = 0,
271 static const struct rt6_info ip6_null_entry_template = {
272 .dst = {
273 .__refcnt = ATOMIC_INIT(1),
274 .__use = 1,
275 .obsolete = DST_OBSOLETE_FORCE_CHK,
276 .error = -ENETUNREACH,
277 .input = ip6_pkt_discard,
278 .output = ip6_pkt_discard_out,
280 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
281 .rt6i_protocol = RTPROT_KERNEL,
282 .rt6i_metric = ~(u32) 0,
283 .rt6i_ref = ATOMIC_INIT(1),
286 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
288 static const struct rt6_info ip6_prohibit_entry_template = {
289 .dst = {
290 .__refcnt = ATOMIC_INIT(1),
291 .__use = 1,
292 .obsolete = DST_OBSOLETE_FORCE_CHK,
293 .error = -EACCES,
294 .input = ip6_pkt_prohibit,
295 .output = ip6_pkt_prohibit_out,
297 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
298 .rt6i_protocol = RTPROT_KERNEL,
299 .rt6i_metric = ~(u32) 0,
300 .rt6i_ref = ATOMIC_INIT(1),
303 static const struct rt6_info ip6_blk_hole_entry_template = {
304 .dst = {
305 .__refcnt = ATOMIC_INIT(1),
306 .__use = 1,
307 .obsolete = DST_OBSOLETE_FORCE_CHK,
308 .error = -EINVAL,
309 .input = dst_discard,
310 .output = dst_discard_out,
312 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
313 .rt6i_protocol = RTPROT_KERNEL,
314 .rt6i_metric = ~(u32) 0,
315 .rt6i_ref = ATOMIC_INIT(1),
318 #endif
320 static void rt6_info_init(struct rt6_info *rt)
322 struct dst_entry *dst = &rt->dst;
324 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
325 INIT_LIST_HEAD(&rt->rt6i_siblings);
326 INIT_LIST_HEAD(&rt->rt6i_uncached);
329 /* allocate dst with ip6_dst_ops */
330 static struct rt6_info *__ip6_dst_alloc(struct net *net,
331 struct net_device *dev,
332 int flags)
334 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
335 0, DST_OBSOLETE_FORCE_CHK, flags);
337 if (rt)
338 rt6_info_init(rt);
340 return rt;
343 struct rt6_info *ip6_dst_alloc(struct net *net,
344 struct net_device *dev,
345 int flags)
347 struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
349 if (rt) {
350 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
351 if (rt->rt6i_pcpu) {
352 int cpu;
354 for_each_possible_cpu(cpu) {
355 struct rt6_info **p;
357 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
358 /* no one shares rt */
359 *p = NULL;
361 } else {
362 dst_destroy((struct dst_entry *)rt);
363 return NULL;
367 return rt;
369 EXPORT_SYMBOL(ip6_dst_alloc);
371 static void ip6_dst_destroy(struct dst_entry *dst)
373 struct rt6_info *rt = (struct rt6_info *)dst;
374 struct dst_entry *from = dst->from;
375 struct inet6_dev *idev;
377 dst_destroy_metrics_generic(dst);
378 free_percpu(rt->rt6i_pcpu);
379 rt6_uncached_list_del(rt);
381 idev = rt->rt6i_idev;
382 if (idev) {
383 rt->rt6i_idev = NULL;
384 in6_dev_put(idev);
387 dst->from = NULL;
388 dst_release(from);
391 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
392 int how)
394 struct rt6_info *rt = (struct rt6_info *)dst;
395 struct inet6_dev *idev = rt->rt6i_idev;
396 struct net_device *loopback_dev =
397 dev_net(dev)->loopback_dev;
399 if (dev != loopback_dev) {
400 if (idev && idev->dev == dev) {
401 struct inet6_dev *loopback_idev =
402 in6_dev_get(loopback_dev);
403 if (loopback_idev) {
404 rt->rt6i_idev = loopback_idev;
405 in6_dev_put(idev);
411 static bool __rt6_check_expired(const struct rt6_info *rt)
413 if (rt->rt6i_flags & RTF_EXPIRES)
414 return time_after(jiffies, rt->dst.expires);
415 else
416 return false;
419 static bool rt6_check_expired(const struct rt6_info *rt)
421 if (rt->rt6i_flags & RTF_EXPIRES) {
422 if (time_after(jiffies, rt->dst.expires))
423 return true;
424 } else if (rt->dst.from) {
425 return rt6_check_expired((struct rt6_info *) rt->dst.from);
427 return false;
430 /* Multipath route selection:
431 * Hash based function using packet header and flowlabel.
432 * Adapted from fib_info_hashfn()
434 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
435 const struct flowi6 *fl6)
437 return get_hash_from_flowi6(fl6) % candidate_count;
440 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
441 struct flowi6 *fl6, int oif,
442 int strict)
444 struct rt6_info *sibling, *next_sibling;
445 int route_choosen;
447 route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
448 /* Don't change the route, if route_choosen == 0
449 * (siblings does not include ourself)
451 if (route_choosen)
452 list_for_each_entry_safe(sibling, next_sibling,
453 &match->rt6i_siblings, rt6i_siblings) {
454 route_choosen--;
455 if (route_choosen == 0) {
456 if (rt6_score_route(sibling, oif, strict) < 0)
457 break;
458 match = sibling;
459 break;
462 return match;
466 * Route lookup. Any table->tb6_lock is implied.
469 static inline struct rt6_info *rt6_device_match(struct net *net,
470 struct rt6_info *rt,
471 const struct in6_addr *saddr,
472 int oif,
473 int flags)
475 struct rt6_info *local = NULL;
476 struct rt6_info *sprt;
478 if (!oif && ipv6_addr_any(saddr))
479 goto out;
481 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
482 struct net_device *dev = sprt->dst.dev;
484 if (oif) {
485 if (dev->ifindex == oif)
486 return sprt;
487 if (dev->flags & IFF_LOOPBACK) {
488 if (!sprt->rt6i_idev ||
489 sprt->rt6i_idev->dev->ifindex != oif) {
490 if (flags & RT6_LOOKUP_F_IFACE)
491 continue;
492 if (local &&
493 local->rt6i_idev->dev->ifindex == oif)
494 continue;
496 local = sprt;
498 } else {
499 if (ipv6_chk_addr(net, saddr, dev,
500 flags & RT6_LOOKUP_F_IFACE))
501 return sprt;
505 if (oif) {
506 if (local)
507 return local;
509 if (flags & RT6_LOOKUP_F_IFACE)
510 return net->ipv6.ip6_null_entry;
512 out:
513 return rt;
516 #ifdef CONFIG_IPV6_ROUTER_PREF
517 struct __rt6_probe_work {
518 struct work_struct work;
519 struct in6_addr target;
520 struct net_device *dev;
523 static void rt6_probe_deferred(struct work_struct *w)
525 struct in6_addr mcaddr;
526 struct __rt6_probe_work *work =
527 container_of(w, struct __rt6_probe_work, work);
529 addrconf_addr_solict_mult(&work->target, &mcaddr);
530 ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
531 dev_put(work->dev);
532 kfree(work);
535 static void rt6_probe(struct rt6_info *rt)
537 struct __rt6_probe_work *work;
538 struct neighbour *neigh;
540 * Okay, this does not seem to be appropriate
541 * for now, however, we need to check if it
542 * is really so; aka Router Reachability Probing.
544 * Router Reachability Probe MUST be rate-limited
545 * to no more than one per minute.
547 if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
548 return;
549 rcu_read_lock_bh();
550 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
551 if (neigh) {
552 if (neigh->nud_state & NUD_VALID)
553 goto out;
555 work = NULL;
556 write_lock(&neigh->lock);
557 if (!(neigh->nud_state & NUD_VALID) &&
558 time_after(jiffies,
559 neigh->updated +
560 rt->rt6i_idev->cnf.rtr_probe_interval)) {
561 work = kmalloc(sizeof(*work), GFP_ATOMIC);
562 if (work)
563 __neigh_set_probe_once(neigh);
565 write_unlock(&neigh->lock);
566 } else {
567 work = kmalloc(sizeof(*work), GFP_ATOMIC);
570 if (work) {
571 INIT_WORK(&work->work, rt6_probe_deferred);
572 work->target = rt->rt6i_gateway;
573 dev_hold(rt->dst.dev);
574 work->dev = rt->dst.dev;
575 schedule_work(&work->work);
578 out:
579 rcu_read_unlock_bh();
581 #else
582 static inline void rt6_probe(struct rt6_info *rt)
585 #endif
588 * Default Router Selection (RFC 2461 6.3.6)
590 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
592 struct net_device *dev = rt->dst.dev;
593 if (!oif || dev->ifindex == oif)
594 return 2;
595 if ((dev->flags & IFF_LOOPBACK) &&
596 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
597 return 1;
598 return 0;
601 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
603 struct neighbour *neigh;
604 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
606 if (rt->rt6i_flags & RTF_NONEXTHOP ||
607 !(rt->rt6i_flags & RTF_GATEWAY))
608 return RT6_NUD_SUCCEED;
610 rcu_read_lock_bh();
611 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
612 if (neigh) {
613 read_lock(&neigh->lock);
614 if (neigh->nud_state & NUD_VALID)
615 ret = RT6_NUD_SUCCEED;
616 #ifdef CONFIG_IPV6_ROUTER_PREF
617 else if (!(neigh->nud_state & NUD_FAILED))
618 ret = RT6_NUD_SUCCEED;
619 else
620 ret = RT6_NUD_FAIL_PROBE;
621 #endif
622 read_unlock(&neigh->lock);
623 } else {
624 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
625 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
627 rcu_read_unlock_bh();
629 return ret;
632 static int rt6_score_route(struct rt6_info *rt, int oif,
633 int strict)
635 int m;
637 m = rt6_check_dev(rt, oif);
638 if (!m && (strict & RT6_LOOKUP_F_IFACE))
639 return RT6_NUD_FAIL_HARD;
640 #ifdef CONFIG_IPV6_ROUTER_PREF
641 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
642 #endif
643 if (strict & RT6_LOOKUP_F_REACHABLE) {
644 int n = rt6_check_neigh(rt);
645 if (n < 0)
646 return n;
648 return m;
651 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
652 int *mpri, struct rt6_info *match,
653 bool *do_rr)
655 int m;
656 bool match_do_rr = false;
657 struct inet6_dev *idev = rt->rt6i_idev;
658 struct net_device *dev = rt->dst.dev;
660 if (dev && !netif_carrier_ok(dev) &&
661 idev->cnf.ignore_routes_with_linkdown &&
662 !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
663 goto out;
665 if (rt6_check_expired(rt))
666 goto out;
668 m = rt6_score_route(rt, oif, strict);
669 if (m == RT6_NUD_FAIL_DO_RR) {
670 match_do_rr = true;
671 m = 0; /* lowest valid score */
672 } else if (m == RT6_NUD_FAIL_HARD) {
673 goto out;
676 if (strict & RT6_LOOKUP_F_REACHABLE)
677 rt6_probe(rt);
679 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
680 if (m > *mpri) {
681 *do_rr = match_do_rr;
682 *mpri = m;
683 match = rt;
685 out:
686 return match;
689 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
690 struct rt6_info *rr_head,
691 u32 metric, int oif, int strict,
692 bool *do_rr)
694 struct rt6_info *rt, *match, *cont;
695 int mpri = -1;
697 match = NULL;
698 cont = NULL;
699 for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
700 if (rt->rt6i_metric != metric) {
701 cont = rt;
702 break;
705 match = find_match(rt, oif, strict, &mpri, match, do_rr);
708 for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
709 if (rt->rt6i_metric != metric) {
710 cont = rt;
711 break;
714 match = find_match(rt, oif, strict, &mpri, match, do_rr);
717 if (match || !cont)
718 return match;
720 for (rt = cont; rt; rt = rt->dst.rt6_next)
721 match = find_match(rt, oif, strict, &mpri, match, do_rr);
723 return match;
726 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
728 struct rt6_info *match, *rt0;
729 struct net *net;
730 bool do_rr = false;
732 rt0 = fn->rr_ptr;
733 if (!rt0)
734 fn->rr_ptr = rt0 = fn->leaf;
736 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
737 &do_rr);
739 if (do_rr) {
740 struct rt6_info *next = rt0->dst.rt6_next;
742 /* no entries matched; do round-robin */
743 if (!next || next->rt6i_metric != rt0->rt6i_metric)
744 next = fn->leaf;
746 if (next != rt0)
747 fn->rr_ptr = next;
750 net = dev_net(rt0->dst.dev);
751 return match ? match : net->ipv6.ip6_null_entry;
754 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
756 return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
759 #ifdef CONFIG_IPV6_ROUTE_INFO
760 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
761 const struct in6_addr *gwaddr)
763 struct net *net = dev_net(dev);
764 struct route_info *rinfo = (struct route_info *) opt;
765 struct in6_addr prefix_buf, *prefix;
766 unsigned int pref;
767 unsigned long lifetime;
768 struct rt6_info *rt;
770 if (len < sizeof(struct route_info)) {
771 return -EINVAL;
774 /* Sanity check for prefix_len and length */
775 if (rinfo->length > 3) {
776 return -EINVAL;
777 } else if (rinfo->prefix_len > 128) {
778 return -EINVAL;
779 } else if (rinfo->prefix_len > 64) {
780 if (rinfo->length < 2) {
781 return -EINVAL;
783 } else if (rinfo->prefix_len > 0) {
784 if (rinfo->length < 1) {
785 return -EINVAL;
789 pref = rinfo->route_pref;
790 if (pref == ICMPV6_ROUTER_PREF_INVALID)
791 return -EINVAL;
793 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
795 if (rinfo->length == 3)
796 prefix = (struct in6_addr *)rinfo->prefix;
797 else {
798 /* this function is safe */
799 ipv6_addr_prefix(&prefix_buf,
800 (struct in6_addr *)rinfo->prefix,
801 rinfo->prefix_len);
802 prefix = &prefix_buf;
805 if (rinfo->prefix_len == 0)
806 rt = rt6_get_dflt_router(gwaddr, dev);
807 else
808 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
809 gwaddr, dev);
811 if (rt && !lifetime) {
812 ip6_del_rt(rt);
813 rt = NULL;
816 if (!rt && lifetime)
817 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
818 dev, pref);
819 else if (rt)
820 rt->rt6i_flags = RTF_ROUTEINFO |
821 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
823 if (rt) {
824 if (!addrconf_finite_timeout(lifetime))
825 rt6_clean_expires(rt);
826 else
827 rt6_set_expires(rt, jiffies + HZ * lifetime);
829 ip6_rt_put(rt);
831 return 0;
833 #endif
835 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
836 struct in6_addr *saddr)
838 struct fib6_node *pn;
839 while (1) {
840 if (fn->fn_flags & RTN_TL_ROOT)
841 return NULL;
842 pn = fn->parent;
843 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
844 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
845 else
846 fn = pn;
847 if (fn->fn_flags & RTN_RTINFO)
848 return fn;
852 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
853 struct fib6_table *table,
854 struct flowi6 *fl6, int flags)
856 struct fib6_node *fn;
857 struct rt6_info *rt;
859 read_lock_bh(&table->tb6_lock);
860 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
861 restart:
862 rt = fn->leaf;
863 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
864 if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
865 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
866 if (rt == net->ipv6.ip6_null_entry) {
867 fn = fib6_backtrack(fn, &fl6->saddr);
868 if (fn)
869 goto restart;
871 dst_use(&rt->dst, jiffies);
872 read_unlock_bh(&table->tb6_lock);
874 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
876 return rt;
880 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
881 int flags)
883 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
885 EXPORT_SYMBOL_GPL(ip6_route_lookup);
887 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
888 const struct in6_addr *saddr, int oif, int strict)
890 struct flowi6 fl6 = {
891 .flowi6_oif = oif,
892 .daddr = *daddr,
894 struct dst_entry *dst;
895 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
897 if (saddr) {
898 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
899 flags |= RT6_LOOKUP_F_HAS_SADDR;
902 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
903 if (dst->error == 0)
904 return (struct rt6_info *) dst;
906 dst_release(dst);
908 return NULL;
910 EXPORT_SYMBOL(rt6_lookup);
912 /* ip6_ins_rt is called with FREE table->tb6_lock.
913 It takes new route entry, the addition fails by any reason the
914 route is freed. In any case, if caller does not hold it, it may
915 be destroyed.
918 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
919 struct mx6_config *mxc)
921 int err;
922 struct fib6_table *table;
924 table = rt->rt6i_table;
925 write_lock_bh(&table->tb6_lock);
926 err = fib6_add(&table->tb6_root, rt, info, mxc);
927 write_unlock_bh(&table->tb6_lock);
929 return err;
932 int ip6_ins_rt(struct rt6_info *rt)
934 struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
935 struct mx6_config mxc = { .mx = NULL, };
937 return __ip6_ins_rt(rt, &info, &mxc);
940 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
941 const struct in6_addr *daddr,
942 const struct in6_addr *saddr)
944 struct rt6_info *rt;
947 * Clone the route.
950 if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
951 ort = (struct rt6_info *)ort->dst.from;
953 rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
955 if (!rt)
956 return NULL;
958 ip6_rt_copy_init(rt, ort);
959 rt->rt6i_flags |= RTF_CACHE;
960 rt->rt6i_metric = 0;
961 rt->dst.flags |= DST_HOST;
962 rt->rt6i_dst.addr = *daddr;
963 rt->rt6i_dst.plen = 128;
965 if (!rt6_is_gw_or_nonexthop(ort)) {
966 if (ort->rt6i_dst.plen != 128 &&
967 ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
968 rt->rt6i_flags |= RTF_ANYCAST;
969 #ifdef CONFIG_IPV6_SUBTREES
970 if (rt->rt6i_src.plen && saddr) {
971 rt->rt6i_src.addr = *saddr;
972 rt->rt6i_src.plen = 128;
974 #endif
977 return rt;
980 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
982 struct rt6_info *pcpu_rt;
984 pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
985 rt->dst.dev, rt->dst.flags);
987 if (!pcpu_rt)
988 return NULL;
989 ip6_rt_copy_init(pcpu_rt, rt);
990 pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
991 pcpu_rt->rt6i_flags |= RTF_PCPU;
992 return pcpu_rt;
995 /* It should be called with read_lock_bh(&tb6_lock) acquired */
996 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
998 struct rt6_info *pcpu_rt, **p;
1000 p = this_cpu_ptr(rt->rt6i_pcpu);
1001 pcpu_rt = *p;
1003 if (pcpu_rt) {
1004 dst_hold(&pcpu_rt->dst);
1005 rt6_dst_from_metrics_check(pcpu_rt);
1007 return pcpu_rt;
1010 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1012 struct fib6_table *table = rt->rt6i_table;
1013 struct rt6_info *pcpu_rt, *prev, **p;
1015 pcpu_rt = ip6_rt_pcpu_alloc(rt);
1016 if (!pcpu_rt) {
1017 struct net *net = dev_net(rt->dst.dev);
1019 dst_hold(&net->ipv6.ip6_null_entry->dst);
1020 return net->ipv6.ip6_null_entry;
1023 read_lock_bh(&table->tb6_lock);
1024 if (rt->rt6i_pcpu) {
1025 p = this_cpu_ptr(rt->rt6i_pcpu);
1026 prev = cmpxchg(p, NULL, pcpu_rt);
1027 if (prev) {
1028 /* If someone did it before us, return prev instead */
1029 dst_destroy(&pcpu_rt->dst);
1030 pcpu_rt = prev;
1032 } else {
1033 /* rt has been removed from the fib6 tree
1034 * before we have a chance to acquire the read_lock.
1035 * In this case, don't brother to create a pcpu rt
1036 * since rt is going away anyway. The next
1037 * dst_check() will trigger a re-lookup.
1039 dst_destroy(&pcpu_rt->dst);
1040 pcpu_rt = rt;
1042 dst_hold(&pcpu_rt->dst);
1043 rt6_dst_from_metrics_check(pcpu_rt);
1044 read_unlock_bh(&table->tb6_lock);
1045 return pcpu_rt;
1048 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
1049 int oif, struct flowi6 *fl6, int flags)
1051 struct fib6_node *fn, *saved_fn;
1052 struct rt6_info *rt;
1053 int strict = 0;
1055 strict |= flags & RT6_LOOKUP_F_IFACE;
1056 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
1057 if (net->ipv6.devconf_all->forwarding == 0)
1058 strict |= RT6_LOOKUP_F_REACHABLE;
1060 read_lock_bh(&table->tb6_lock);
1062 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1063 saved_fn = fn;
1065 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1066 oif = 0;
1068 redo_rt6_select:
1069 rt = rt6_select(fn, oif, strict);
1070 if (rt->rt6i_nsiblings)
1071 rt = rt6_multipath_select(rt, fl6, oif, strict);
1072 if (rt == net->ipv6.ip6_null_entry) {
1073 fn = fib6_backtrack(fn, &fl6->saddr);
1074 if (fn)
1075 goto redo_rt6_select;
1076 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1077 /* also consider unreachable route */
1078 strict &= ~RT6_LOOKUP_F_REACHABLE;
1079 fn = saved_fn;
1080 goto redo_rt6_select;
1085 if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1086 dst_use(&rt->dst, jiffies);
1087 read_unlock_bh(&table->tb6_lock);
1089 rt6_dst_from_metrics_check(rt);
1091 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1092 return rt;
1093 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1094 !(rt->rt6i_flags & RTF_GATEWAY))) {
1095 /* Create a RTF_CACHE clone which will not be
1096 * owned by the fib6 tree. It is for the special case where
1097 * the daddr in the skb during the neighbor look-up is different
1098 * from the fl6->daddr used to look-up route here.
1101 struct rt6_info *uncached_rt;
1103 dst_use(&rt->dst, jiffies);
1104 read_unlock_bh(&table->tb6_lock);
1106 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1107 dst_release(&rt->dst);
1109 if (uncached_rt)
1110 rt6_uncached_list_add(uncached_rt);
1111 else
1112 uncached_rt = net->ipv6.ip6_null_entry;
1114 dst_hold(&uncached_rt->dst);
1116 trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
1117 return uncached_rt;
1119 } else {
1120 /* Get a percpu copy */
1122 struct rt6_info *pcpu_rt;
1124 rt->dst.lastuse = jiffies;
1125 rt->dst.__use++;
1126 pcpu_rt = rt6_get_pcpu_route(rt);
1128 if (pcpu_rt) {
1129 read_unlock_bh(&table->tb6_lock);
1130 } else {
1131 /* We have to do the read_unlock first
1132 * because rt6_make_pcpu_route() may trigger
1133 * ip6_dst_gc() which will take the write_lock.
1135 dst_hold(&rt->dst);
1136 read_unlock_bh(&table->tb6_lock);
1137 pcpu_rt = rt6_make_pcpu_route(rt);
1138 dst_release(&rt->dst);
1141 trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
1142 return pcpu_rt;
1146 EXPORT_SYMBOL_GPL(ip6_pol_route);
1148 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1149 struct flowi6 *fl6, int flags)
1151 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1154 struct dst_entry *ip6_route_input_lookup(struct net *net,
1155 struct net_device *dev,
1156 struct flowi6 *fl6, int flags)
1158 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1159 flags |= RT6_LOOKUP_F_IFACE;
1161 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1163 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
1165 void ip6_route_input(struct sk_buff *skb)
1167 const struct ipv6hdr *iph = ipv6_hdr(skb);
1168 struct net *net = dev_net(skb->dev);
1169 int flags = RT6_LOOKUP_F_HAS_SADDR;
1170 struct ip_tunnel_info *tun_info;
1171 struct flowi6 fl6 = {
1172 .flowi6_iif = skb->dev->ifindex,
1173 .daddr = iph->daddr,
1174 .saddr = iph->saddr,
1175 .flowlabel = ip6_flowinfo(iph),
1176 .flowi6_mark = skb->mark,
1177 .flowi6_proto = iph->nexthdr,
1180 tun_info = skb_tunnel_info(skb);
1181 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1182 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1183 skb_dst_drop(skb);
1184 skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1187 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1188 struct flowi6 *fl6, int flags)
1190 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1193 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1194 struct flowi6 *fl6, int flags)
1196 bool any_src;
1198 if (rt6_need_strict(&fl6->daddr)) {
1199 struct dst_entry *dst;
1201 dst = l3mdev_link_scope_lookup(net, fl6);
1202 if (dst)
1203 return dst;
1206 fl6->flowi6_iif = LOOPBACK_IFINDEX;
1208 any_src = ipv6_addr_any(&fl6->saddr);
1209 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1210 (fl6->flowi6_oif && any_src))
1211 flags |= RT6_LOOKUP_F_IFACE;
1213 if (!any_src)
1214 flags |= RT6_LOOKUP_F_HAS_SADDR;
1215 else if (sk)
1216 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1218 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1220 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1222 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1224 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1225 struct dst_entry *new = NULL;
1227 rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1228 if (rt) {
1229 rt6_info_init(rt);
1231 new = &rt->dst;
1232 new->__use = 1;
1233 new->input = dst_discard;
1234 new->output = dst_discard_out;
1236 dst_copy_metrics(new, &ort->dst);
1237 rt->rt6i_idev = ort->rt6i_idev;
1238 if (rt->rt6i_idev)
1239 in6_dev_hold(rt->rt6i_idev);
1241 rt->rt6i_gateway = ort->rt6i_gateway;
1242 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1243 rt->rt6i_metric = 0;
1245 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1246 #ifdef CONFIG_IPV6_SUBTREES
1247 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1248 #endif
1250 dst_free(new);
1253 dst_release(dst_orig);
1254 return new ? new : ERR_PTR(-ENOMEM);
1258 * Destination cache support functions
1261 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1263 if (rt->dst.from &&
1264 dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1265 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1268 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1270 if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1271 return NULL;
1273 if (rt6_check_expired(rt))
1274 return NULL;
1276 return &rt->dst;
1279 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1281 if (!__rt6_check_expired(rt) &&
1282 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1283 rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1284 return &rt->dst;
1285 else
1286 return NULL;
1289 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1291 struct rt6_info *rt;
1293 rt = (struct rt6_info *) dst;
1295 /* All IPV6 dsts are created with ->obsolete set to the value
1296 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1297 * into this function always.
1300 rt6_dst_from_metrics_check(rt);
1302 if (rt->rt6i_flags & RTF_PCPU ||
1303 (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1304 return rt6_dst_from_check(rt, cookie);
1305 else
1306 return rt6_check(rt, cookie);
1309 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1311 struct rt6_info *rt = (struct rt6_info *) dst;
1313 if (rt) {
1314 if (rt->rt6i_flags & RTF_CACHE) {
1315 if (rt6_check_expired(rt)) {
1316 ip6_del_rt(rt);
1317 dst = NULL;
1319 } else {
1320 dst_release(dst);
1321 dst = NULL;
1324 return dst;
1327 static void ip6_link_failure(struct sk_buff *skb)
1329 struct rt6_info *rt;
1331 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1333 rt = (struct rt6_info *) skb_dst(skb);
1334 if (rt) {
1335 if (rt->rt6i_flags & RTF_CACHE) {
1336 dst_hold(&rt->dst);
1337 ip6_del_rt(rt);
1338 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1339 rt->rt6i_node->fn_sernum = -1;
1344 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1346 struct net *net = dev_net(rt->dst.dev);
1348 rt->rt6i_flags |= RTF_MODIFIED;
1349 rt->rt6i_pmtu = mtu;
1350 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1353 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1355 return !(rt->rt6i_flags & RTF_CACHE) &&
1356 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1359 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1360 const struct ipv6hdr *iph, u32 mtu)
1362 struct rt6_info *rt6 = (struct rt6_info *)dst;
1364 if (rt6->rt6i_flags & RTF_LOCAL)
1365 return;
1367 if (dst_metric_locked(dst, RTAX_MTU))
1368 return;
1370 dst_confirm(dst);
1371 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1372 if (mtu >= dst_mtu(dst))
1373 return;
1375 if (!rt6_cache_allowed_for_pmtu(rt6)) {
1376 rt6_do_update_pmtu(rt6, mtu);
1377 } else {
1378 const struct in6_addr *daddr, *saddr;
1379 struct rt6_info *nrt6;
1381 if (iph) {
1382 daddr = &iph->daddr;
1383 saddr = &iph->saddr;
1384 } else if (sk) {
1385 daddr = &sk->sk_v6_daddr;
1386 saddr = &inet6_sk(sk)->saddr;
1387 } else {
1388 return;
1390 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1391 if (nrt6) {
1392 rt6_do_update_pmtu(nrt6, mtu);
1394 /* ip6_ins_rt(nrt6) will bump the
1395 * rt6->rt6i_node->fn_sernum
1396 * which will fail the next rt6_check() and
1397 * invalidate the sk->sk_dst_cache.
1399 ip6_ins_rt(nrt6);
1404 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1405 struct sk_buff *skb, u32 mtu)
1407 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1410 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1411 int oif, u32 mark, kuid_t uid)
1413 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1414 struct dst_entry *dst;
1415 struct flowi6 fl6;
1417 memset(&fl6, 0, sizeof(fl6));
1418 fl6.flowi6_oif = oif;
1419 fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1420 fl6.daddr = iph->daddr;
1421 fl6.saddr = iph->saddr;
1422 fl6.flowlabel = ip6_flowinfo(iph);
1423 fl6.flowi6_uid = uid;
1425 dst = ip6_route_output(net, NULL, &fl6);
1426 if (!dst->error)
1427 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1428 dst_release(dst);
1430 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1432 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1434 struct dst_entry *dst;
1436 ip6_update_pmtu(skb, sock_net(sk), mtu,
1437 sk->sk_bound_dev_if, sk->sk_mark, sk->sk_uid);
1439 dst = __sk_dst_get(sk);
1440 if (!dst || !dst->obsolete ||
1441 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
1442 return;
1444 bh_lock_sock(sk);
1445 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1446 ip6_datagram_dst_update(sk, false);
1447 bh_unlock_sock(sk);
1449 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1451 /* Handle redirects */
1452 struct ip6rd_flowi {
1453 struct flowi6 fl6;
1454 struct in6_addr gateway;
1457 static struct rt6_info *__ip6_route_redirect(struct net *net,
1458 struct fib6_table *table,
1459 struct flowi6 *fl6,
1460 int flags)
1462 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1463 struct rt6_info *rt;
1464 struct fib6_node *fn;
1466 /* Get the "current" route for this destination and
1467 * check if the redirect has come from appropriate router.
1469 * RFC 4861 specifies that redirects should only be
1470 * accepted if they come from the nexthop to the target.
1471 * Due to the way the routes are chosen, this notion
1472 * is a bit fuzzy and one might need to check all possible
1473 * routes.
1476 read_lock_bh(&table->tb6_lock);
1477 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1478 restart:
1479 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1480 if (rt6_check_expired(rt))
1481 continue;
1482 if (rt->dst.error)
1483 break;
1484 if (!(rt->rt6i_flags & RTF_GATEWAY))
1485 continue;
1486 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1487 continue;
1488 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1489 continue;
1490 break;
1493 if (!rt)
1494 rt = net->ipv6.ip6_null_entry;
1495 else if (rt->dst.error) {
1496 rt = net->ipv6.ip6_null_entry;
1497 goto out;
1500 if (rt == net->ipv6.ip6_null_entry) {
1501 fn = fib6_backtrack(fn, &fl6->saddr);
1502 if (fn)
1503 goto restart;
1506 out:
1507 dst_hold(&rt->dst);
1509 read_unlock_bh(&table->tb6_lock);
1511 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1512 return rt;
1515 static struct dst_entry *ip6_route_redirect(struct net *net,
1516 const struct flowi6 *fl6,
1517 const struct in6_addr *gateway)
1519 int flags = RT6_LOOKUP_F_HAS_SADDR;
1520 struct ip6rd_flowi rdfl;
1522 rdfl.fl6 = *fl6;
1523 rdfl.gateway = *gateway;
1525 return fib6_rule_lookup(net, &rdfl.fl6,
1526 flags, __ip6_route_redirect);
1529 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
1530 kuid_t uid)
1532 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1533 struct dst_entry *dst;
1534 struct flowi6 fl6;
1536 memset(&fl6, 0, sizeof(fl6));
1537 fl6.flowi6_iif = LOOPBACK_IFINDEX;
1538 fl6.flowi6_oif = oif;
1539 fl6.flowi6_mark = mark;
1540 fl6.daddr = iph->daddr;
1541 fl6.saddr = iph->saddr;
1542 fl6.flowlabel = ip6_flowinfo(iph);
1543 fl6.flowi6_uid = uid;
1545 dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1546 rt6_do_redirect(dst, NULL, skb);
1547 dst_release(dst);
1549 EXPORT_SYMBOL_GPL(ip6_redirect);
1551 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1552 u32 mark)
1554 const struct ipv6hdr *iph = ipv6_hdr(skb);
1555 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1556 struct dst_entry *dst;
1557 struct flowi6 fl6;
1559 memset(&fl6, 0, sizeof(fl6));
1560 fl6.flowi6_iif = LOOPBACK_IFINDEX;
1561 fl6.flowi6_oif = oif;
1562 fl6.flowi6_mark = mark;
1563 fl6.daddr = msg->dest;
1564 fl6.saddr = iph->daddr;
1565 fl6.flowi6_uid = sock_net_uid(net, NULL);
1567 dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1568 rt6_do_redirect(dst, NULL, skb);
1569 dst_release(dst);
1572 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1574 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
1575 sk->sk_uid);
1577 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1579 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1581 struct net_device *dev = dst->dev;
1582 unsigned int mtu = dst_mtu(dst);
1583 struct net *net = dev_net(dev);
1585 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1587 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1588 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1591 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1592 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1593 * IPV6_MAXPLEN is also valid and means: "any MSS,
1594 * rely only on pmtu discovery"
1596 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1597 mtu = IPV6_MAXPLEN;
1598 return mtu;
1601 static unsigned int ip6_mtu(const struct dst_entry *dst)
1603 const struct rt6_info *rt = (const struct rt6_info *)dst;
1604 unsigned int mtu = rt->rt6i_pmtu;
1605 struct inet6_dev *idev;
1607 if (mtu)
1608 goto out;
1610 mtu = dst_metric_raw(dst, RTAX_MTU);
1611 if (mtu)
1612 goto out;
1614 mtu = IPV6_MIN_MTU;
1616 rcu_read_lock();
1617 idev = __in6_dev_get(dst->dev);
1618 if (idev)
1619 mtu = idev->cnf.mtu6;
1620 rcu_read_unlock();
1622 out:
1623 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1625 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
1628 static struct dst_entry *icmp6_dst_gc_list;
1629 static DEFINE_SPINLOCK(icmp6_dst_lock);
1631 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1632 struct flowi6 *fl6)
1634 struct dst_entry *dst;
1635 struct rt6_info *rt;
1636 struct inet6_dev *idev = in6_dev_get(dev);
1637 struct net *net = dev_net(dev);
1639 if (unlikely(!idev))
1640 return ERR_PTR(-ENODEV);
1642 rt = ip6_dst_alloc(net, dev, 0);
1643 if (unlikely(!rt)) {
1644 in6_dev_put(idev);
1645 dst = ERR_PTR(-ENOMEM);
1646 goto out;
1649 rt->dst.flags |= DST_HOST;
1650 rt->dst.output = ip6_output;
1651 atomic_set(&rt->dst.__refcnt, 1);
1652 rt->rt6i_gateway = fl6->daddr;
1653 rt->rt6i_dst.addr = fl6->daddr;
1654 rt->rt6i_dst.plen = 128;
1655 rt->rt6i_idev = idev;
1656 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1658 spin_lock_bh(&icmp6_dst_lock);
1659 rt->dst.next = icmp6_dst_gc_list;
1660 icmp6_dst_gc_list = &rt->dst;
1661 spin_unlock_bh(&icmp6_dst_lock);
1663 fib6_force_start_gc(net);
1665 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1667 out:
1668 return dst;
1671 int icmp6_dst_gc(void)
1673 struct dst_entry *dst, **pprev;
1674 int more = 0;
1676 spin_lock_bh(&icmp6_dst_lock);
1677 pprev = &icmp6_dst_gc_list;
1679 while ((dst = *pprev) != NULL) {
1680 if (!atomic_read(&dst->__refcnt)) {
1681 *pprev = dst->next;
1682 dst_free(dst);
1683 } else {
1684 pprev = &dst->next;
1685 ++more;
1689 spin_unlock_bh(&icmp6_dst_lock);
1691 return more;
1694 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1695 void *arg)
1697 struct dst_entry *dst, **pprev;
1699 spin_lock_bh(&icmp6_dst_lock);
1700 pprev = &icmp6_dst_gc_list;
1701 while ((dst = *pprev) != NULL) {
1702 struct rt6_info *rt = (struct rt6_info *) dst;
1703 if (func(rt, arg)) {
1704 *pprev = dst->next;
1705 dst_free(dst);
1706 } else {
1707 pprev = &dst->next;
1710 spin_unlock_bh(&icmp6_dst_lock);
1713 static int ip6_dst_gc(struct dst_ops *ops)
1715 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1716 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1717 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1718 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1719 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1720 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1721 int entries;
1723 entries = dst_entries_get_fast(ops);
1724 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1725 entries <= rt_max_size)
1726 goto out;
1728 net->ipv6.ip6_rt_gc_expire++;
1729 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1730 entries = dst_entries_get_slow(ops);
1731 if (entries < ops->gc_thresh)
1732 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1733 out:
1734 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1735 return entries > rt_max_size;
1738 static int ip6_convert_metrics(struct mx6_config *mxc,
1739 const struct fib6_config *cfg)
1741 bool ecn_ca = false;
1742 struct nlattr *nla;
1743 int remaining;
1744 u32 *mp;
1746 if (!cfg->fc_mx)
1747 return 0;
1749 mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1750 if (unlikely(!mp))
1751 return -ENOMEM;
1753 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1754 int type = nla_type(nla);
1755 u32 val;
1757 if (!type)
1758 continue;
1759 if (unlikely(type > RTAX_MAX))
1760 goto err;
1762 if (type == RTAX_CC_ALGO) {
1763 char tmp[TCP_CA_NAME_MAX];
1765 nla_strlcpy(tmp, nla, sizeof(tmp));
1766 val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1767 if (val == TCP_CA_UNSPEC)
1768 goto err;
1769 } else {
1770 val = nla_get_u32(nla);
1772 if (type == RTAX_HOPLIMIT && val > 255)
1773 val = 255;
1774 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1775 goto err;
1777 mp[type - 1] = val;
1778 __set_bit(type - 1, mxc->mx_valid);
1781 if (ecn_ca) {
1782 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1783 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1786 mxc->mx = mp;
1787 return 0;
1788 err:
1789 kfree(mp);
1790 return -EINVAL;
1793 static struct rt6_info *ip6_nh_lookup_table(struct net *net,
1794 struct fib6_config *cfg,
1795 const struct in6_addr *gw_addr)
1797 struct flowi6 fl6 = {
1798 .flowi6_oif = cfg->fc_ifindex,
1799 .daddr = *gw_addr,
1800 .saddr = cfg->fc_prefsrc,
1802 struct fib6_table *table;
1803 struct rt6_info *rt;
1804 int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_IGNORE_LINKSTATE;
1806 table = fib6_get_table(net, cfg->fc_table);
1807 if (!table)
1808 return NULL;
1810 if (!ipv6_addr_any(&cfg->fc_prefsrc))
1811 flags |= RT6_LOOKUP_F_HAS_SADDR;
1813 rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags);
1815 /* if table lookup failed, fall back to full lookup */
1816 if (rt == net->ipv6.ip6_null_entry) {
1817 ip6_rt_put(rt);
1818 rt = NULL;
1821 return rt;
1824 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1826 struct net *net = cfg->fc_nlinfo.nl_net;
1827 struct rt6_info *rt = NULL;
1828 struct net_device *dev = NULL;
1829 struct inet6_dev *idev = NULL;
1830 struct fib6_table *table;
1831 int addr_type;
1832 int err = -EINVAL;
1834 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1835 goto out;
1836 #ifndef CONFIG_IPV6_SUBTREES
1837 if (cfg->fc_src_len)
1838 goto out;
1839 #endif
1840 if (cfg->fc_ifindex) {
1841 err = -ENODEV;
1842 dev = dev_get_by_index(net, cfg->fc_ifindex);
1843 if (!dev)
1844 goto out;
1845 idev = in6_dev_get(dev);
1846 if (!idev)
1847 goto out;
1850 if (cfg->fc_metric == 0)
1851 cfg->fc_metric = IP6_RT_PRIO_USER;
1853 err = -ENOBUFS;
1854 if (cfg->fc_nlinfo.nlh &&
1855 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1856 table = fib6_get_table(net, cfg->fc_table);
1857 if (!table) {
1858 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1859 table = fib6_new_table(net, cfg->fc_table);
1861 } else {
1862 table = fib6_new_table(net, cfg->fc_table);
1865 if (!table)
1866 goto out;
1868 rt = ip6_dst_alloc(net, NULL,
1869 (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1871 if (!rt) {
1872 err = -ENOMEM;
1873 goto out;
1876 if (cfg->fc_flags & RTF_EXPIRES)
1877 rt6_set_expires(rt, jiffies +
1878 clock_t_to_jiffies(cfg->fc_expires));
1879 else
1880 rt6_clean_expires(rt);
1882 if (cfg->fc_protocol == RTPROT_UNSPEC)
1883 cfg->fc_protocol = RTPROT_BOOT;
1884 rt->rt6i_protocol = cfg->fc_protocol;
1886 addr_type = ipv6_addr_type(&cfg->fc_dst);
1888 if (addr_type & IPV6_ADDR_MULTICAST)
1889 rt->dst.input = ip6_mc_input;
1890 else if (cfg->fc_flags & RTF_LOCAL)
1891 rt->dst.input = ip6_input;
1892 else
1893 rt->dst.input = ip6_forward;
1895 rt->dst.output = ip6_output;
1897 if (cfg->fc_encap) {
1898 struct lwtunnel_state *lwtstate;
1900 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1901 cfg->fc_encap, AF_INET6, cfg,
1902 &lwtstate);
1903 if (err)
1904 goto out;
1905 rt->dst.lwtstate = lwtstate_get(lwtstate);
1906 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1907 rt->dst.lwtstate->orig_output = rt->dst.output;
1908 rt->dst.output = lwtunnel_output;
1910 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1911 rt->dst.lwtstate->orig_input = rt->dst.input;
1912 rt->dst.input = lwtunnel_input;
1916 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1917 rt->rt6i_dst.plen = cfg->fc_dst_len;
1918 if (rt->rt6i_dst.plen == 128)
1919 rt->dst.flags |= DST_HOST;
1921 #ifdef CONFIG_IPV6_SUBTREES
1922 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1923 rt->rt6i_src.plen = cfg->fc_src_len;
1924 #endif
1926 rt->rt6i_metric = cfg->fc_metric;
1928 /* We cannot add true routes via loopback here,
1929 they would result in kernel looping; promote them to reject routes
1931 if ((cfg->fc_flags & RTF_REJECT) ||
1932 (dev && (dev->flags & IFF_LOOPBACK) &&
1933 !(addr_type & IPV6_ADDR_LOOPBACK) &&
1934 !(cfg->fc_flags & RTF_LOCAL))) {
1935 /* hold loopback dev/idev if we haven't done so. */
1936 if (dev != net->loopback_dev) {
1937 if (dev) {
1938 dev_put(dev);
1939 in6_dev_put(idev);
1941 dev = net->loopback_dev;
1942 dev_hold(dev);
1943 idev = in6_dev_get(dev);
1944 if (!idev) {
1945 err = -ENODEV;
1946 goto out;
1949 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1950 switch (cfg->fc_type) {
1951 case RTN_BLACKHOLE:
1952 rt->dst.error = -EINVAL;
1953 rt->dst.output = dst_discard_out;
1954 rt->dst.input = dst_discard;
1955 break;
1956 case RTN_PROHIBIT:
1957 rt->dst.error = -EACCES;
1958 rt->dst.output = ip6_pkt_prohibit_out;
1959 rt->dst.input = ip6_pkt_prohibit;
1960 break;
1961 case RTN_THROW:
1962 case RTN_UNREACHABLE:
1963 default:
1964 rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1965 : (cfg->fc_type == RTN_UNREACHABLE)
1966 ? -EHOSTUNREACH : -ENETUNREACH;
1967 rt->dst.output = ip6_pkt_discard_out;
1968 rt->dst.input = ip6_pkt_discard;
1969 break;
1971 goto install_route;
1974 if (cfg->fc_flags & RTF_GATEWAY) {
1975 const struct in6_addr *gw_addr;
1976 int gwa_type;
1978 gw_addr = &cfg->fc_gateway;
1979 gwa_type = ipv6_addr_type(gw_addr);
1981 /* if gw_addr is local we will fail to detect this in case
1982 * address is still TENTATIVE (DAD in progress). rt6_lookup()
1983 * will return already-added prefix route via interface that
1984 * prefix route was assigned to, which might be non-loopback.
1986 err = -EINVAL;
1987 if (ipv6_chk_addr_and_flags(net, gw_addr,
1988 gwa_type & IPV6_ADDR_LINKLOCAL ?
1989 dev : NULL, 0, 0))
1990 goto out;
1992 rt->rt6i_gateway = *gw_addr;
1994 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1995 struct rt6_info *grt = NULL;
1997 /* IPv6 strictly inhibits using not link-local
1998 addresses as nexthop address.
1999 Otherwise, router will not able to send redirects.
2000 It is very good, but in some (rare!) circumstances
2001 (SIT, PtP, NBMA NOARP links) it is handy to allow
2002 some exceptions. --ANK
2003 We allow IPv4-mapped nexthops to support RFC4798-type
2004 addressing
2006 if (!(gwa_type & (IPV6_ADDR_UNICAST |
2007 IPV6_ADDR_MAPPED)))
2008 goto out;
2010 if (cfg->fc_table) {
2011 grt = ip6_nh_lookup_table(net, cfg, gw_addr);
2013 if (grt) {
2014 if (grt->rt6i_flags & RTF_GATEWAY ||
2015 (dev && dev != grt->dst.dev)) {
2016 ip6_rt_put(grt);
2017 grt = NULL;
2022 if (!grt)
2023 grt = rt6_lookup(net, gw_addr, NULL,
2024 cfg->fc_ifindex, 1);
2026 err = -EHOSTUNREACH;
2027 if (!grt)
2028 goto out;
2029 if (dev) {
2030 if (dev != grt->dst.dev) {
2031 ip6_rt_put(grt);
2032 goto out;
2034 } else {
2035 dev = grt->dst.dev;
2036 idev = grt->rt6i_idev;
2037 dev_hold(dev);
2038 in6_dev_hold(grt->rt6i_idev);
2040 if (!(grt->rt6i_flags & RTF_GATEWAY))
2041 err = 0;
2042 ip6_rt_put(grt);
2044 if (err)
2045 goto out;
2047 err = -EINVAL;
2048 if (!dev || (dev->flags & IFF_LOOPBACK))
2049 goto out;
2052 err = -ENODEV;
2053 if (!dev)
2054 goto out;
2056 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
2057 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
2058 err = -EINVAL;
2059 goto out;
2061 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
2062 rt->rt6i_prefsrc.plen = 128;
2063 } else
2064 rt->rt6i_prefsrc.plen = 0;
2066 rt->rt6i_flags = cfg->fc_flags;
2068 install_route:
2069 rt->dst.dev = dev;
2070 rt->rt6i_idev = idev;
2071 rt->rt6i_table = table;
2073 cfg->fc_nlinfo.nl_net = dev_net(dev);
2075 return rt;
2076 out:
2077 if (dev)
2078 dev_put(dev);
2079 if (idev)
2080 in6_dev_put(idev);
2081 if (rt)
2082 dst_free(&rt->dst);
2084 return ERR_PTR(err);
2087 int ip6_route_add(struct fib6_config *cfg)
2089 struct mx6_config mxc = { .mx = NULL, };
2090 struct rt6_info *rt;
2091 int err;
2093 rt = ip6_route_info_create(cfg);
2094 if (IS_ERR(rt)) {
2095 err = PTR_ERR(rt);
2096 rt = NULL;
2097 goto out;
2100 err = ip6_convert_metrics(&mxc, cfg);
2101 if (err)
2102 goto out;
2104 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2106 kfree(mxc.mx);
2108 return err;
2109 out:
2110 if (rt)
2111 dst_free(&rt->dst);
2113 return err;
2116 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2118 int err;
2119 struct fib6_table *table;
2120 struct net *net = dev_net(rt->dst.dev);
2122 if (rt == net->ipv6.ip6_null_entry ||
2123 rt->dst.flags & DST_NOCACHE) {
2124 err = -ENOENT;
2125 goto out;
2128 table = rt->rt6i_table;
2129 write_lock_bh(&table->tb6_lock);
2130 err = fib6_del(rt, info);
2131 write_unlock_bh(&table->tb6_lock);
2133 out:
2134 ip6_rt_put(rt);
2135 return err;
2138 int ip6_del_rt(struct rt6_info *rt)
2140 struct nl_info info = {
2141 .nl_net = dev_net(rt->dst.dev),
2143 return __ip6_del_rt(rt, &info);
2146 static int ip6_route_del(struct fib6_config *cfg)
2148 struct fib6_table *table;
2149 struct fib6_node *fn;
2150 struct rt6_info *rt;
2151 int err = -ESRCH;
2153 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2154 if (!table)
2155 return err;
2157 read_lock_bh(&table->tb6_lock);
2159 fn = fib6_locate(&table->tb6_root,
2160 &cfg->fc_dst, cfg->fc_dst_len,
2161 &cfg->fc_src, cfg->fc_src_len);
2163 if (fn) {
2164 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2165 if ((rt->rt6i_flags & RTF_CACHE) &&
2166 !(cfg->fc_flags & RTF_CACHE))
2167 continue;
2168 if (cfg->fc_ifindex &&
2169 (!rt->dst.dev ||
2170 rt->dst.dev->ifindex != cfg->fc_ifindex))
2171 continue;
2172 if (cfg->fc_flags & RTF_GATEWAY &&
2173 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2174 continue;
2175 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2176 continue;
2177 if (cfg->fc_protocol && cfg->fc_protocol != rt->rt6i_protocol)
2178 continue;
2179 dst_hold(&rt->dst);
2180 read_unlock_bh(&table->tb6_lock);
2182 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2185 read_unlock_bh(&table->tb6_lock);
2187 return err;
2190 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2192 struct netevent_redirect netevent;
2193 struct rt6_info *rt, *nrt = NULL;
2194 struct ndisc_options ndopts;
2195 struct inet6_dev *in6_dev;
2196 struct neighbour *neigh;
2197 struct rd_msg *msg;
2198 int optlen, on_link;
2199 u8 *lladdr;
2201 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2202 optlen -= sizeof(*msg);
2204 if (optlen < 0) {
2205 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2206 return;
2209 msg = (struct rd_msg *)icmp6_hdr(skb);
2211 if (ipv6_addr_is_multicast(&msg->dest)) {
2212 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2213 return;
2216 on_link = 0;
2217 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2218 on_link = 1;
2219 } else if (ipv6_addr_type(&msg->target) !=
2220 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2221 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2222 return;
2225 in6_dev = __in6_dev_get(skb->dev);
2226 if (!in6_dev)
2227 return;
2228 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2229 return;
2231 /* RFC2461 8.1:
2232 * The IP source address of the Redirect MUST be the same as the current
2233 * first-hop router for the specified ICMP Destination Address.
2236 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
2237 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2238 return;
2241 lladdr = NULL;
2242 if (ndopts.nd_opts_tgt_lladdr) {
2243 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2244 skb->dev);
2245 if (!lladdr) {
2246 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2247 return;
2251 rt = (struct rt6_info *) dst;
2252 if (rt->rt6i_flags & RTF_REJECT) {
2253 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2254 return;
2257 /* Redirect received -> path was valid.
2258 * Look, redirects are sent only in response to data packets,
2259 * so that this nexthop apparently is reachable. --ANK
2261 dst_confirm(&rt->dst);
2263 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2264 if (!neigh)
2265 return;
2268 * We have finally decided to accept it.
2271 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
2272 NEIGH_UPDATE_F_WEAK_OVERRIDE|
2273 NEIGH_UPDATE_F_OVERRIDE|
2274 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2275 NEIGH_UPDATE_F_ISROUTER)),
2276 NDISC_REDIRECT, &ndopts);
2278 nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2279 if (!nrt)
2280 goto out;
2282 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2283 if (on_link)
2284 nrt->rt6i_flags &= ~RTF_GATEWAY;
2286 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2288 if (ip6_ins_rt(nrt))
2289 goto out;
2291 netevent.old = &rt->dst;
2292 netevent.new = &nrt->dst;
2293 netevent.daddr = &msg->dest;
2294 netevent.neigh = neigh;
2295 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2297 if (rt->rt6i_flags & RTF_CACHE) {
2298 rt = (struct rt6_info *) dst_clone(&rt->dst);
2299 ip6_del_rt(rt);
2302 out:
2303 neigh_release(neigh);
2307 * Misc support functions
2310 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2312 BUG_ON(from->dst.from);
2314 rt->rt6i_flags &= ~RTF_EXPIRES;
2315 dst_hold(&from->dst);
2316 rt->dst.from = &from->dst;
2317 dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2320 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2322 rt->dst.input = ort->dst.input;
2323 rt->dst.output = ort->dst.output;
2324 rt->rt6i_dst = ort->rt6i_dst;
2325 rt->dst.error = ort->dst.error;
2326 rt->rt6i_idev = ort->rt6i_idev;
2327 if (rt->rt6i_idev)
2328 in6_dev_hold(rt->rt6i_idev);
2329 rt->dst.lastuse = jiffies;
2330 rt->rt6i_gateway = ort->rt6i_gateway;
2331 rt->rt6i_flags = ort->rt6i_flags;
2332 rt6_set_from(rt, ort);
2333 rt->rt6i_metric = ort->rt6i_metric;
2334 #ifdef CONFIG_IPV6_SUBTREES
2335 rt->rt6i_src = ort->rt6i_src;
2336 #endif
2337 rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2338 rt->rt6i_table = ort->rt6i_table;
2339 rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2342 #ifdef CONFIG_IPV6_ROUTE_INFO
2343 static struct rt6_info *rt6_get_route_info(struct net *net,
2344 const struct in6_addr *prefix, int prefixlen,
2345 const struct in6_addr *gwaddr,
2346 struct net_device *dev)
2348 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
2349 int ifindex = dev->ifindex;
2350 struct fib6_node *fn;
2351 struct rt6_info *rt = NULL;
2352 struct fib6_table *table;
2354 table = fib6_get_table(net, tb_id);
2355 if (!table)
2356 return NULL;
2358 read_lock_bh(&table->tb6_lock);
2359 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2360 if (!fn)
2361 goto out;
2363 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2364 if (rt->dst.dev->ifindex != ifindex)
2365 continue;
2366 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2367 continue;
2368 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2369 continue;
2370 dst_hold(&rt->dst);
2371 break;
2373 out:
2374 read_unlock_bh(&table->tb6_lock);
2375 return rt;
2378 static struct rt6_info *rt6_add_route_info(struct net *net,
2379 const struct in6_addr *prefix, int prefixlen,
2380 const struct in6_addr *gwaddr,
2381 struct net_device *dev,
2382 unsigned int pref)
2384 struct fib6_config cfg = {
2385 .fc_metric = IP6_RT_PRIO_USER,
2386 .fc_ifindex = dev->ifindex,
2387 .fc_dst_len = prefixlen,
2388 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2389 RTF_UP | RTF_PREF(pref),
2390 .fc_nlinfo.portid = 0,
2391 .fc_nlinfo.nlh = NULL,
2392 .fc_nlinfo.nl_net = net,
2395 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
2396 cfg.fc_dst = *prefix;
2397 cfg.fc_gateway = *gwaddr;
2399 /* We should treat it as a default route if prefix length is 0. */
2400 if (!prefixlen)
2401 cfg.fc_flags |= RTF_DEFAULT;
2403 ip6_route_add(&cfg);
2405 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
2407 #endif
2409 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2411 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
2412 struct rt6_info *rt;
2413 struct fib6_table *table;
2415 table = fib6_get_table(dev_net(dev), tb_id);
2416 if (!table)
2417 return NULL;
2419 read_lock_bh(&table->tb6_lock);
2420 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2421 if (dev == rt->dst.dev &&
2422 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2423 ipv6_addr_equal(&rt->rt6i_gateway, addr))
2424 break;
2426 if (rt)
2427 dst_hold(&rt->dst);
2428 read_unlock_bh(&table->tb6_lock);
2429 return rt;
2432 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2433 struct net_device *dev,
2434 unsigned int pref)
2436 struct fib6_config cfg = {
2437 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2438 .fc_metric = IP6_RT_PRIO_USER,
2439 .fc_ifindex = dev->ifindex,
2440 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2441 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2442 .fc_nlinfo.portid = 0,
2443 .fc_nlinfo.nlh = NULL,
2444 .fc_nlinfo.nl_net = dev_net(dev),
2447 cfg.fc_gateway = *gwaddr;
2449 if (!ip6_route_add(&cfg)) {
2450 struct fib6_table *table;
2452 table = fib6_get_table(dev_net(dev), cfg.fc_table);
2453 if (table)
2454 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
2457 return rt6_get_dflt_router(gwaddr, dev);
2460 static void __rt6_purge_dflt_routers(struct fib6_table *table)
2462 struct rt6_info *rt;
2464 restart:
2465 read_lock_bh(&table->tb6_lock);
2466 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2467 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2468 (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2469 dst_hold(&rt->dst);
2470 read_unlock_bh(&table->tb6_lock);
2471 ip6_del_rt(rt);
2472 goto restart;
2475 read_unlock_bh(&table->tb6_lock);
2477 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
2480 void rt6_purge_dflt_routers(struct net *net)
2482 struct fib6_table *table;
2483 struct hlist_head *head;
2484 unsigned int h;
2486 rcu_read_lock();
2488 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
2489 head = &net->ipv6.fib_table_hash[h];
2490 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
2491 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
2492 __rt6_purge_dflt_routers(table);
2496 rcu_read_unlock();
2499 static void rtmsg_to_fib6_config(struct net *net,
2500 struct in6_rtmsg *rtmsg,
2501 struct fib6_config *cfg)
2503 memset(cfg, 0, sizeof(*cfg));
2505 cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2506 : RT6_TABLE_MAIN;
2507 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2508 cfg->fc_metric = rtmsg->rtmsg_metric;
2509 cfg->fc_expires = rtmsg->rtmsg_info;
2510 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2511 cfg->fc_src_len = rtmsg->rtmsg_src_len;
2512 cfg->fc_flags = rtmsg->rtmsg_flags;
2514 cfg->fc_nlinfo.nl_net = net;
2516 cfg->fc_dst = rtmsg->rtmsg_dst;
2517 cfg->fc_src = rtmsg->rtmsg_src;
2518 cfg->fc_gateway = rtmsg->rtmsg_gateway;
2521 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2523 struct fib6_config cfg;
2524 struct in6_rtmsg rtmsg;
2525 int err;
2527 switch (cmd) {
2528 case SIOCADDRT: /* Add a route */
2529 case SIOCDELRT: /* Delete a route */
2530 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2531 return -EPERM;
2532 err = copy_from_user(&rtmsg, arg,
2533 sizeof(struct in6_rtmsg));
2534 if (err)
2535 return -EFAULT;
2537 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2539 rtnl_lock();
2540 switch (cmd) {
2541 case SIOCADDRT:
2542 err = ip6_route_add(&cfg);
2543 break;
2544 case SIOCDELRT:
2545 err = ip6_route_del(&cfg);
2546 break;
2547 default:
2548 err = -EINVAL;
2550 rtnl_unlock();
2552 return err;
2555 return -EINVAL;
2559 * Drop the packet on the floor
2562 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2564 int type;
2565 struct dst_entry *dst = skb_dst(skb);
2566 switch (ipstats_mib_noroutes) {
2567 case IPSTATS_MIB_INNOROUTES:
2568 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2569 if (type == IPV6_ADDR_ANY) {
2570 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2571 IPSTATS_MIB_INADDRERRORS);
2572 break;
2574 /* FALLTHROUGH */
2575 case IPSTATS_MIB_OUTNOROUTES:
2576 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2577 ipstats_mib_noroutes);
2578 break;
2580 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2581 kfree_skb(skb);
2582 return 0;
2585 static int ip6_pkt_discard(struct sk_buff *skb)
2587 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2590 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2592 skb->dev = skb_dst(skb)->dev;
2593 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2596 static int ip6_pkt_prohibit(struct sk_buff *skb)
2598 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2601 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2603 skb->dev = skb_dst(skb)->dev;
2604 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2608 * Allocate a dst for local (unicast / anycast) address.
2611 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2612 const struct in6_addr *addr,
2613 bool anycast)
2615 u32 tb_id;
2616 struct net *net = dev_net(idev->dev);
2617 struct net_device *dev = net->loopback_dev;
2618 struct rt6_info *rt;
2620 /* use L3 Master device as loopback for host routes if device
2621 * is enslaved and address is not link local or multicast
2623 if (!rt6_need_strict(addr))
2624 dev = l3mdev_master_dev_rcu(idev->dev) ? : dev;
2626 rt = ip6_dst_alloc(net, dev, DST_NOCOUNT);
2627 if (!rt)
2628 return ERR_PTR(-ENOMEM);
2630 in6_dev_hold(idev);
2632 rt->dst.flags |= DST_HOST;
2633 rt->dst.input = ip6_input;
2634 rt->dst.output = ip6_output;
2635 rt->rt6i_idev = idev;
2637 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2638 if (anycast)
2639 rt->rt6i_flags |= RTF_ANYCAST;
2640 else
2641 rt->rt6i_flags |= RTF_LOCAL;
2643 rt->rt6i_gateway = *addr;
2644 rt->rt6i_dst.addr = *addr;
2645 rt->rt6i_dst.plen = 128;
2646 tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2647 rt->rt6i_table = fib6_get_table(net, tb_id);
2648 rt->dst.flags |= DST_NOCACHE;
2650 atomic_set(&rt->dst.__refcnt, 1);
2652 return rt;
2655 /* remove deleted ip from prefsrc entries */
2656 struct arg_dev_net_ip {
2657 struct net_device *dev;
2658 struct net *net;
2659 struct in6_addr *addr;
2662 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2664 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2665 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2666 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2668 if (((void *)rt->dst.dev == dev || !dev) &&
2669 rt != net->ipv6.ip6_null_entry &&
2670 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2671 /* remove prefsrc entry */
2672 rt->rt6i_prefsrc.plen = 0;
2674 return 0;
2677 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2679 struct net *net = dev_net(ifp->idev->dev);
2680 struct arg_dev_net_ip adni = {
2681 .dev = ifp->idev->dev,
2682 .net = net,
2683 .addr = &ifp->addr,
2685 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2688 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2689 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2691 /* Remove routers and update dst entries when gateway turn into host. */
2692 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2694 struct in6_addr *gateway = (struct in6_addr *)arg;
2696 if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2697 ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2698 ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2699 return -1;
2701 return 0;
2704 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2706 fib6_clean_all(net, fib6_clean_tohost, gateway);
2709 struct arg_dev_net {
2710 struct net_device *dev;
2711 struct net *net;
2714 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2716 const struct arg_dev_net *adn = arg;
2717 const struct net_device *dev = adn->dev;
2719 if ((rt->dst.dev == dev || !dev) &&
2720 rt != adn->net->ipv6.ip6_null_entry)
2721 return -1;
2723 return 0;
2726 void rt6_ifdown(struct net *net, struct net_device *dev)
2728 struct arg_dev_net adn = {
2729 .dev = dev,
2730 .net = net,
2733 fib6_clean_all(net, fib6_ifdown, &adn);
2734 icmp6_clean_all(fib6_ifdown, &adn);
2735 if (dev)
2736 rt6_uncached_list_flush_dev(net, dev);
2739 struct rt6_mtu_change_arg {
2740 struct net_device *dev;
2741 unsigned int mtu;
2744 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2746 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2747 struct inet6_dev *idev;
2749 /* In IPv6 pmtu discovery is not optional,
2750 so that RTAX_MTU lock cannot disable it.
2751 We still use this lock to block changes
2752 caused by addrconf/ndisc.
2755 idev = __in6_dev_get(arg->dev);
2756 if (!idev)
2757 return 0;
2759 /* For administrative MTU increase, there is no way to discover
2760 IPv6 PMTU increase, so PMTU increase should be updated here.
2761 Since RFC 1981 doesn't include administrative MTU increase
2762 update PMTU increase is a MUST. (i.e. jumbo frame)
2765 If new MTU is less than route PMTU, this new MTU will be the
2766 lowest MTU in the path, update the route PMTU to reflect PMTU
2767 decreases; if new MTU is greater than route PMTU, and the
2768 old MTU is the lowest MTU in the path, update the route PMTU
2769 to reflect the increase. In this case if the other nodes' MTU
2770 also have the lowest MTU, TOO BIG MESSAGE will be lead to
2771 PMTU discovery.
2773 if (rt->dst.dev == arg->dev &&
2774 dst_metric_raw(&rt->dst, RTAX_MTU) &&
2775 !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2776 if (rt->rt6i_flags & RTF_CACHE) {
2777 /* For RTF_CACHE with rt6i_pmtu == 0
2778 * (i.e. a redirected route),
2779 * the metrics of its rt->dst.from has already
2780 * been updated.
2782 if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2783 rt->rt6i_pmtu = arg->mtu;
2784 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2785 (dst_mtu(&rt->dst) < arg->mtu &&
2786 dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2787 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2790 return 0;
2793 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2795 struct rt6_mtu_change_arg arg = {
2796 .dev = dev,
2797 .mtu = mtu,
2800 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2803 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2804 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2805 [RTA_OIF] = { .type = NLA_U32 },
2806 [RTA_IIF] = { .type = NLA_U32 },
2807 [RTA_PRIORITY] = { .type = NLA_U32 },
2808 [RTA_METRICS] = { .type = NLA_NESTED },
2809 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2810 [RTA_PREF] = { .type = NLA_U8 },
2811 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
2812 [RTA_ENCAP] = { .type = NLA_NESTED },
2813 [RTA_EXPIRES] = { .type = NLA_U32 },
2814 [RTA_UID] = { .type = NLA_U32 },
2817 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2818 struct fib6_config *cfg)
2820 struct rtmsg *rtm;
2821 struct nlattr *tb[RTA_MAX+1];
2822 unsigned int pref;
2823 int err;
2825 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2826 if (err < 0)
2827 goto errout;
2829 err = -EINVAL;
2830 rtm = nlmsg_data(nlh);
2831 memset(cfg, 0, sizeof(*cfg));
2833 cfg->fc_table = rtm->rtm_table;
2834 cfg->fc_dst_len = rtm->rtm_dst_len;
2835 cfg->fc_src_len = rtm->rtm_src_len;
2836 cfg->fc_flags = RTF_UP;
2837 cfg->fc_protocol = rtm->rtm_protocol;
2838 cfg->fc_type = rtm->rtm_type;
2840 if (rtm->rtm_type == RTN_UNREACHABLE ||
2841 rtm->rtm_type == RTN_BLACKHOLE ||
2842 rtm->rtm_type == RTN_PROHIBIT ||
2843 rtm->rtm_type == RTN_THROW)
2844 cfg->fc_flags |= RTF_REJECT;
2846 if (rtm->rtm_type == RTN_LOCAL)
2847 cfg->fc_flags |= RTF_LOCAL;
2849 if (rtm->rtm_flags & RTM_F_CLONED)
2850 cfg->fc_flags |= RTF_CACHE;
2852 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2853 cfg->fc_nlinfo.nlh = nlh;
2854 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2856 if (tb[RTA_GATEWAY]) {
2857 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2858 cfg->fc_flags |= RTF_GATEWAY;
2861 if (tb[RTA_DST]) {
2862 int plen = (rtm->rtm_dst_len + 7) >> 3;
2864 if (nla_len(tb[RTA_DST]) < plen)
2865 goto errout;
2867 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2870 if (tb[RTA_SRC]) {
2871 int plen = (rtm->rtm_src_len + 7) >> 3;
2873 if (nla_len(tb[RTA_SRC]) < plen)
2874 goto errout;
2876 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2879 if (tb[RTA_PREFSRC])
2880 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2882 if (tb[RTA_OIF])
2883 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2885 if (tb[RTA_PRIORITY])
2886 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2888 if (tb[RTA_METRICS]) {
2889 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2890 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2893 if (tb[RTA_TABLE])
2894 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2896 if (tb[RTA_MULTIPATH]) {
2897 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2898 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2900 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
2901 cfg->fc_mp_len);
2902 if (err < 0)
2903 goto errout;
2906 if (tb[RTA_PREF]) {
2907 pref = nla_get_u8(tb[RTA_PREF]);
2908 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2909 pref != ICMPV6_ROUTER_PREF_HIGH)
2910 pref = ICMPV6_ROUTER_PREF_MEDIUM;
2911 cfg->fc_flags |= RTF_PREF(pref);
2914 if (tb[RTA_ENCAP])
2915 cfg->fc_encap = tb[RTA_ENCAP];
2917 if (tb[RTA_ENCAP_TYPE]) {
2918 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2920 err = lwtunnel_valid_encap_type(cfg->fc_encap_type);
2921 if (err < 0)
2922 goto errout;
2925 if (tb[RTA_EXPIRES]) {
2926 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
2928 if (addrconf_finite_timeout(timeout)) {
2929 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
2930 cfg->fc_flags |= RTF_EXPIRES;
2934 err = 0;
2935 errout:
2936 return err;
2939 struct rt6_nh {
2940 struct rt6_info *rt6_info;
2941 struct fib6_config r_cfg;
2942 struct mx6_config mxc;
2943 struct list_head next;
2946 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2948 struct rt6_nh *nh;
2950 list_for_each_entry(nh, rt6_nh_list, next) {
2951 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2952 &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2953 nh->r_cfg.fc_ifindex);
2957 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2958 struct rt6_info *rt, struct fib6_config *r_cfg)
2960 struct rt6_nh *nh;
2961 struct rt6_info *rtnh;
2962 int err = -EEXIST;
2964 list_for_each_entry(nh, rt6_nh_list, next) {
2965 /* check if rt6_info already exists */
2966 rtnh = nh->rt6_info;
2968 if (rtnh->dst.dev == rt->dst.dev &&
2969 rtnh->rt6i_idev == rt->rt6i_idev &&
2970 ipv6_addr_equal(&rtnh->rt6i_gateway,
2971 &rt->rt6i_gateway))
2972 return err;
2975 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2976 if (!nh)
2977 return -ENOMEM;
2978 nh->rt6_info = rt;
2979 err = ip6_convert_metrics(&nh->mxc, r_cfg);
2980 if (err) {
2981 kfree(nh);
2982 return err;
2984 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2985 list_add_tail(&nh->next, rt6_nh_list);
2987 return 0;
2990 static int ip6_route_multipath_add(struct fib6_config *cfg)
2992 struct fib6_config r_cfg;
2993 struct rtnexthop *rtnh;
2994 struct rt6_info *rt;
2995 struct rt6_nh *err_nh;
2996 struct rt6_nh *nh, *nh_safe;
2997 int remaining;
2998 int attrlen;
2999 int err = 1;
3000 int nhn = 0;
3001 int replace = (cfg->fc_nlinfo.nlh &&
3002 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
3003 LIST_HEAD(rt6_nh_list);
3005 remaining = cfg->fc_mp_len;
3006 rtnh = (struct rtnexthop *)cfg->fc_mp;
3008 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
3009 * rt6_info structs per nexthop
3011 while (rtnh_ok(rtnh, remaining)) {
3012 memcpy(&r_cfg, cfg, sizeof(*cfg));
3013 if (rtnh->rtnh_ifindex)
3014 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3016 attrlen = rtnh_attrlen(rtnh);
3017 if (attrlen > 0) {
3018 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3020 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3021 if (nla) {
3022 r_cfg.fc_gateway = nla_get_in6_addr(nla);
3023 r_cfg.fc_flags |= RTF_GATEWAY;
3025 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
3026 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
3027 if (nla)
3028 r_cfg.fc_encap_type = nla_get_u16(nla);
3031 rt = ip6_route_info_create(&r_cfg);
3032 if (IS_ERR(rt)) {
3033 err = PTR_ERR(rt);
3034 rt = NULL;
3035 goto cleanup;
3038 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
3039 if (err) {
3040 dst_free(&rt->dst);
3041 goto cleanup;
3044 rtnh = rtnh_next(rtnh, &remaining);
3047 err_nh = NULL;
3048 list_for_each_entry(nh, &rt6_nh_list, next) {
3049 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
3050 /* nh->rt6_info is used or freed at this point, reset to NULL*/
3051 nh->rt6_info = NULL;
3052 if (err) {
3053 if (replace && nhn)
3054 ip6_print_replace_route_err(&rt6_nh_list);
3055 err_nh = nh;
3056 goto add_errout;
3059 /* Because each route is added like a single route we remove
3060 * these flags after the first nexthop: if there is a collision,
3061 * we have already failed to add the first nexthop:
3062 * fib6_add_rt2node() has rejected it; when replacing, old
3063 * nexthops have been replaced by first new, the rest should
3064 * be added to it.
3066 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
3067 NLM_F_REPLACE);
3068 nhn++;
3071 goto cleanup;
3073 add_errout:
3074 /* Delete routes that were already added */
3075 list_for_each_entry(nh, &rt6_nh_list, next) {
3076 if (err_nh == nh)
3077 break;
3078 ip6_route_del(&nh->r_cfg);
3081 cleanup:
3082 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
3083 if (nh->rt6_info)
3084 dst_free(&nh->rt6_info->dst);
3085 kfree(nh->mxc.mx);
3086 list_del(&nh->next);
3087 kfree(nh);
3090 return err;
3093 static int ip6_route_multipath_del(struct fib6_config *cfg)
3095 struct fib6_config r_cfg;
3096 struct rtnexthop *rtnh;
3097 int remaining;
3098 int attrlen;
3099 int err = 1, last_err = 0;
3101 remaining = cfg->fc_mp_len;
3102 rtnh = (struct rtnexthop *)cfg->fc_mp;
3104 /* Parse a Multipath Entry */
3105 while (rtnh_ok(rtnh, remaining)) {
3106 memcpy(&r_cfg, cfg, sizeof(*cfg));
3107 if (rtnh->rtnh_ifindex)
3108 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3110 attrlen = rtnh_attrlen(rtnh);
3111 if (attrlen > 0) {
3112 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3114 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3115 if (nla) {
3116 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3117 r_cfg.fc_flags |= RTF_GATEWAY;
3120 err = ip6_route_del(&r_cfg);
3121 if (err)
3122 last_err = err;
3124 rtnh = rtnh_next(rtnh, &remaining);
3127 return last_err;
3130 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3132 struct fib6_config cfg;
3133 int err;
3135 err = rtm_to_fib6_config(skb, nlh, &cfg);
3136 if (err < 0)
3137 return err;
3139 if (cfg.fc_mp)
3140 return ip6_route_multipath_del(&cfg);
3141 else
3142 return ip6_route_del(&cfg);
3145 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3147 struct fib6_config cfg;
3148 int err;
3150 err = rtm_to_fib6_config(skb, nlh, &cfg);
3151 if (err < 0)
3152 return err;
3154 if (cfg.fc_mp)
3155 return ip6_route_multipath_add(&cfg);
3156 else
3157 return ip6_route_add(&cfg);
3160 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3162 return NLMSG_ALIGN(sizeof(struct rtmsg))
3163 + nla_total_size(16) /* RTA_SRC */
3164 + nla_total_size(16) /* RTA_DST */
3165 + nla_total_size(16) /* RTA_GATEWAY */
3166 + nla_total_size(16) /* RTA_PREFSRC */
3167 + nla_total_size(4) /* RTA_TABLE */
3168 + nla_total_size(4) /* RTA_IIF */
3169 + nla_total_size(4) /* RTA_OIF */
3170 + nla_total_size(4) /* RTA_PRIORITY */
3171 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3172 + nla_total_size(sizeof(struct rta_cacheinfo))
3173 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3174 + nla_total_size(1) /* RTA_PREF */
3175 + lwtunnel_get_encap_size(rt->dst.lwtstate);
3178 static int rt6_fill_node(struct net *net,
3179 struct sk_buff *skb, struct rt6_info *rt,
3180 struct in6_addr *dst, struct in6_addr *src,
3181 int iif, int type, u32 portid, u32 seq,
3182 int prefix, int nowait, unsigned int flags)
3184 u32 metrics[RTAX_MAX];
3185 struct rtmsg *rtm;
3186 struct nlmsghdr *nlh;
3187 long expires;
3188 u32 table;
3190 if (prefix) { /* user wants prefix routes only */
3191 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3192 /* success since this is not a prefix route */
3193 return 1;
3197 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3198 if (!nlh)
3199 return -EMSGSIZE;
3201 rtm = nlmsg_data(nlh);
3202 rtm->rtm_family = AF_INET6;
3203 rtm->rtm_dst_len = rt->rt6i_dst.plen;
3204 rtm->rtm_src_len = rt->rt6i_src.plen;
3205 rtm->rtm_tos = 0;
3206 if (rt->rt6i_table)
3207 table = rt->rt6i_table->tb6_id;
3208 else
3209 table = RT6_TABLE_UNSPEC;
3210 rtm->rtm_table = table;
3211 if (nla_put_u32(skb, RTA_TABLE, table))
3212 goto nla_put_failure;
3213 if (rt->rt6i_flags & RTF_REJECT) {
3214 switch (rt->dst.error) {
3215 case -EINVAL:
3216 rtm->rtm_type = RTN_BLACKHOLE;
3217 break;
3218 case -EACCES:
3219 rtm->rtm_type = RTN_PROHIBIT;
3220 break;
3221 case -EAGAIN:
3222 rtm->rtm_type = RTN_THROW;
3223 break;
3224 default:
3225 rtm->rtm_type = RTN_UNREACHABLE;
3226 break;
3229 else if (rt->rt6i_flags & RTF_LOCAL)
3230 rtm->rtm_type = RTN_LOCAL;
3231 else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3232 rtm->rtm_type = RTN_LOCAL;
3233 else
3234 rtm->rtm_type = RTN_UNICAST;
3235 rtm->rtm_flags = 0;
3236 if (!netif_carrier_ok(rt->dst.dev)) {
3237 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3238 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3239 rtm->rtm_flags |= RTNH_F_DEAD;
3241 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3242 rtm->rtm_protocol = rt->rt6i_protocol;
3243 if (rt->rt6i_flags & RTF_DYNAMIC)
3244 rtm->rtm_protocol = RTPROT_REDIRECT;
3245 else if (rt->rt6i_flags & RTF_ADDRCONF) {
3246 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3247 rtm->rtm_protocol = RTPROT_RA;
3248 else
3249 rtm->rtm_protocol = RTPROT_KERNEL;
3252 if (rt->rt6i_flags & RTF_CACHE)
3253 rtm->rtm_flags |= RTM_F_CLONED;
3255 if (dst) {
3256 if (nla_put_in6_addr(skb, RTA_DST, dst))
3257 goto nla_put_failure;
3258 rtm->rtm_dst_len = 128;
3259 } else if (rtm->rtm_dst_len)
3260 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3261 goto nla_put_failure;
3262 #ifdef CONFIG_IPV6_SUBTREES
3263 if (src) {
3264 if (nla_put_in6_addr(skb, RTA_SRC, src))
3265 goto nla_put_failure;
3266 rtm->rtm_src_len = 128;
3267 } else if (rtm->rtm_src_len &&
3268 nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3269 goto nla_put_failure;
3270 #endif
3271 if (iif) {
3272 #ifdef CONFIG_IPV6_MROUTE
3273 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3274 int err = ip6mr_get_route(net, skb, rtm, nowait,
3275 portid);
3277 if (err <= 0) {
3278 if (!nowait) {
3279 if (err == 0)
3280 return 0;
3281 goto nla_put_failure;
3282 } else {
3283 if (err == -EMSGSIZE)
3284 goto nla_put_failure;
3287 } else
3288 #endif
3289 if (nla_put_u32(skb, RTA_IIF, iif))
3290 goto nla_put_failure;
3291 } else if (dst) {
3292 struct in6_addr saddr_buf;
3293 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3294 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3295 goto nla_put_failure;
3298 if (rt->rt6i_prefsrc.plen) {
3299 struct in6_addr saddr_buf;
3300 saddr_buf = rt->rt6i_prefsrc.addr;
3301 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3302 goto nla_put_failure;
3305 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3306 if (rt->rt6i_pmtu)
3307 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3308 if (rtnetlink_put_metrics(skb, metrics) < 0)
3309 goto nla_put_failure;
3311 if (rt->rt6i_flags & RTF_GATEWAY) {
3312 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3313 goto nla_put_failure;
3316 if (rt->dst.dev &&
3317 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3318 goto nla_put_failure;
3319 if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3320 goto nla_put_failure;
3322 expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3324 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3325 goto nla_put_failure;
3327 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3328 goto nla_put_failure;
3330 if (lwtunnel_fill_encap(skb, rt->dst.lwtstate) < 0)
3331 goto nla_put_failure;
3333 nlmsg_end(skb, nlh);
3334 return 0;
3336 nla_put_failure:
3337 nlmsg_cancel(skb, nlh);
3338 return -EMSGSIZE;
3341 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3343 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3344 int prefix;
3346 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3347 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3348 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3349 } else
3350 prefix = 0;
3352 return rt6_fill_node(arg->net,
3353 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3354 NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3355 prefix, 0, NLM_F_MULTI);
3358 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3360 struct net *net = sock_net(in_skb->sk);
3361 struct nlattr *tb[RTA_MAX+1];
3362 struct rt6_info *rt;
3363 struct sk_buff *skb;
3364 struct rtmsg *rtm;
3365 struct flowi6 fl6;
3366 int err, iif = 0, oif = 0;
3368 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3369 if (err < 0)
3370 goto errout;
3372 err = -EINVAL;
3373 memset(&fl6, 0, sizeof(fl6));
3374 rtm = nlmsg_data(nlh);
3375 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
3377 if (tb[RTA_SRC]) {
3378 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3379 goto errout;
3381 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3384 if (tb[RTA_DST]) {
3385 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3386 goto errout;
3388 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3391 if (tb[RTA_IIF])
3392 iif = nla_get_u32(tb[RTA_IIF]);
3394 if (tb[RTA_OIF])
3395 oif = nla_get_u32(tb[RTA_OIF]);
3397 if (tb[RTA_MARK])
3398 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3400 if (tb[RTA_UID])
3401 fl6.flowi6_uid = make_kuid(current_user_ns(),
3402 nla_get_u32(tb[RTA_UID]));
3403 else
3404 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
3406 if (iif) {
3407 struct net_device *dev;
3408 int flags = 0;
3410 dev = __dev_get_by_index(net, iif);
3411 if (!dev) {
3412 err = -ENODEV;
3413 goto errout;
3416 fl6.flowi6_iif = iif;
3418 if (!ipv6_addr_any(&fl6.saddr))
3419 flags |= RT6_LOOKUP_F_HAS_SADDR;
3421 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3422 flags);
3423 } else {
3424 fl6.flowi6_oif = oif;
3426 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3429 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3430 if (!skb) {
3431 ip6_rt_put(rt);
3432 err = -ENOBUFS;
3433 goto errout;
3436 /* Reserve room for dummy headers, this skb can pass
3437 through good chunk of routing engine.
3439 skb_reset_mac_header(skb);
3440 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3442 skb_dst_set(skb, &rt->dst);
3444 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3445 RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3446 nlh->nlmsg_seq, 0, 0, 0);
3447 if (err < 0) {
3448 kfree_skb(skb);
3449 goto errout;
3452 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3453 errout:
3454 return err;
3457 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3458 unsigned int nlm_flags)
3460 struct sk_buff *skb;
3461 struct net *net = info->nl_net;
3462 u32 seq;
3463 int err;
3465 err = -ENOBUFS;
3466 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3468 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3469 if (!skb)
3470 goto errout;
3472 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3473 event, info->portid, seq, 0, 0, nlm_flags);
3474 if (err < 0) {
3475 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3476 WARN_ON(err == -EMSGSIZE);
3477 kfree_skb(skb);
3478 goto errout;
3480 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3481 info->nlh, gfp_any());
3482 return;
3483 errout:
3484 if (err < 0)
3485 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3488 static int ip6_route_dev_notify(struct notifier_block *this,
3489 unsigned long event, void *ptr)
3491 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3492 struct net *net = dev_net(dev);
3494 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3495 net->ipv6.ip6_null_entry->dst.dev = dev;
3496 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3497 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3498 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3499 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3500 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3501 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3502 #endif
3505 return NOTIFY_OK;
3509 * /proc
3512 #ifdef CONFIG_PROC_FS
3514 static const struct file_operations ipv6_route_proc_fops = {
3515 .owner = THIS_MODULE,
3516 .open = ipv6_route_open,
3517 .read = seq_read,
3518 .llseek = seq_lseek,
3519 .release = seq_release_net,
3522 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3524 struct net *net = (struct net *)seq->private;
3525 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3526 net->ipv6.rt6_stats->fib_nodes,
3527 net->ipv6.rt6_stats->fib_route_nodes,
3528 net->ipv6.rt6_stats->fib_rt_alloc,
3529 net->ipv6.rt6_stats->fib_rt_entries,
3530 net->ipv6.rt6_stats->fib_rt_cache,
3531 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3532 net->ipv6.rt6_stats->fib_discarded_routes);
3534 return 0;
3537 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3539 return single_open_net(inode, file, rt6_stats_seq_show);
3542 static const struct file_operations rt6_stats_seq_fops = {
3543 .owner = THIS_MODULE,
3544 .open = rt6_stats_seq_open,
3545 .read = seq_read,
3546 .llseek = seq_lseek,
3547 .release = single_release_net,
3549 #endif /* CONFIG_PROC_FS */
3551 #ifdef CONFIG_SYSCTL
3553 static
3554 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3555 void __user *buffer, size_t *lenp, loff_t *ppos)
3557 struct net *net;
3558 int delay;
3559 if (!write)
3560 return -EINVAL;
3562 net = (struct net *)ctl->extra1;
3563 delay = net->ipv6.sysctl.flush_delay;
3564 proc_dointvec(ctl, write, buffer, lenp, ppos);
3565 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3566 return 0;
3569 struct ctl_table ipv6_route_table_template[] = {
3571 .procname = "flush",
3572 .data = &init_net.ipv6.sysctl.flush_delay,
3573 .maxlen = sizeof(int),
3574 .mode = 0200,
3575 .proc_handler = ipv6_sysctl_rtcache_flush
3578 .procname = "gc_thresh",
3579 .data = &ip6_dst_ops_template.gc_thresh,
3580 .maxlen = sizeof(int),
3581 .mode = 0644,
3582 .proc_handler = proc_dointvec,
3585 .procname = "max_size",
3586 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
3587 .maxlen = sizeof(int),
3588 .mode = 0644,
3589 .proc_handler = proc_dointvec,
3592 .procname = "gc_min_interval",
3593 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3594 .maxlen = sizeof(int),
3595 .mode = 0644,
3596 .proc_handler = proc_dointvec_jiffies,
3599 .procname = "gc_timeout",
3600 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3601 .maxlen = sizeof(int),
3602 .mode = 0644,
3603 .proc_handler = proc_dointvec_jiffies,
3606 .procname = "gc_interval",
3607 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3608 .maxlen = sizeof(int),
3609 .mode = 0644,
3610 .proc_handler = proc_dointvec_jiffies,
3613 .procname = "gc_elasticity",
3614 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3615 .maxlen = sizeof(int),
3616 .mode = 0644,
3617 .proc_handler = proc_dointvec,
3620 .procname = "mtu_expires",
3621 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3622 .maxlen = sizeof(int),
3623 .mode = 0644,
3624 .proc_handler = proc_dointvec_jiffies,
3627 .procname = "min_adv_mss",
3628 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3629 .maxlen = sizeof(int),
3630 .mode = 0644,
3631 .proc_handler = proc_dointvec,
3634 .procname = "gc_min_interval_ms",
3635 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3636 .maxlen = sizeof(int),
3637 .mode = 0644,
3638 .proc_handler = proc_dointvec_ms_jiffies,
3643 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3645 struct ctl_table *table;
3647 table = kmemdup(ipv6_route_table_template,
3648 sizeof(ipv6_route_table_template),
3649 GFP_KERNEL);
3651 if (table) {
3652 table[0].data = &net->ipv6.sysctl.flush_delay;
3653 table[0].extra1 = net;
3654 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3655 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3656 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3657 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3658 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3659 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3660 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3661 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3662 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3664 /* Don't export sysctls to unprivileged users */
3665 if (net->user_ns != &init_user_ns)
3666 table[0].procname = NULL;
3669 return table;
3671 #endif
3673 static int __net_init ip6_route_net_init(struct net *net)
3675 int ret = -ENOMEM;
3677 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3678 sizeof(net->ipv6.ip6_dst_ops));
3680 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3681 goto out_ip6_dst_ops;
3683 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3684 sizeof(*net->ipv6.ip6_null_entry),
3685 GFP_KERNEL);
3686 if (!net->ipv6.ip6_null_entry)
3687 goto out_ip6_dst_entries;
3688 net->ipv6.ip6_null_entry->dst.path =
3689 (struct dst_entry *)net->ipv6.ip6_null_entry;
3690 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3691 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3692 ip6_template_metrics, true);
3694 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3695 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3696 sizeof(*net->ipv6.ip6_prohibit_entry),
3697 GFP_KERNEL);
3698 if (!net->ipv6.ip6_prohibit_entry)
3699 goto out_ip6_null_entry;
3700 net->ipv6.ip6_prohibit_entry->dst.path =
3701 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3702 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3703 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3704 ip6_template_metrics, true);
3706 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3707 sizeof(*net->ipv6.ip6_blk_hole_entry),
3708 GFP_KERNEL);
3709 if (!net->ipv6.ip6_blk_hole_entry)
3710 goto out_ip6_prohibit_entry;
3711 net->ipv6.ip6_blk_hole_entry->dst.path =
3712 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3713 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3714 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3715 ip6_template_metrics, true);
3716 #endif
3718 net->ipv6.sysctl.flush_delay = 0;
3719 net->ipv6.sysctl.ip6_rt_max_size = 4096;
3720 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3721 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3722 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3723 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3724 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3725 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3727 net->ipv6.ip6_rt_gc_expire = 30*HZ;
3729 ret = 0;
3730 out:
3731 return ret;
3733 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3734 out_ip6_prohibit_entry:
3735 kfree(net->ipv6.ip6_prohibit_entry);
3736 out_ip6_null_entry:
3737 kfree(net->ipv6.ip6_null_entry);
3738 #endif
3739 out_ip6_dst_entries:
3740 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3741 out_ip6_dst_ops:
3742 goto out;
3745 static void __net_exit ip6_route_net_exit(struct net *net)
3747 kfree(net->ipv6.ip6_null_entry);
3748 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3749 kfree(net->ipv6.ip6_prohibit_entry);
3750 kfree(net->ipv6.ip6_blk_hole_entry);
3751 #endif
3752 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3755 static int __net_init ip6_route_net_init_late(struct net *net)
3757 #ifdef CONFIG_PROC_FS
3758 proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3759 proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3760 #endif
3761 return 0;
3764 static void __net_exit ip6_route_net_exit_late(struct net *net)
3766 #ifdef CONFIG_PROC_FS
3767 remove_proc_entry("ipv6_route", net->proc_net);
3768 remove_proc_entry("rt6_stats", net->proc_net);
3769 #endif
3772 static struct pernet_operations ip6_route_net_ops = {
3773 .init = ip6_route_net_init,
3774 .exit = ip6_route_net_exit,
3777 static int __net_init ipv6_inetpeer_init(struct net *net)
3779 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3781 if (!bp)
3782 return -ENOMEM;
3783 inet_peer_base_init(bp);
3784 net->ipv6.peers = bp;
3785 return 0;
3788 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3790 struct inet_peer_base *bp = net->ipv6.peers;
3792 net->ipv6.peers = NULL;
3793 inetpeer_invalidate_tree(bp);
3794 kfree(bp);
3797 static struct pernet_operations ipv6_inetpeer_ops = {
3798 .init = ipv6_inetpeer_init,
3799 .exit = ipv6_inetpeer_exit,
3802 static struct pernet_operations ip6_route_net_late_ops = {
3803 .init = ip6_route_net_init_late,
3804 .exit = ip6_route_net_exit_late,
3807 static struct notifier_block ip6_route_dev_notifier = {
3808 .notifier_call = ip6_route_dev_notify,
3809 .priority = 0,
3812 int __init ip6_route_init(void)
3814 int ret;
3815 int cpu;
3817 ret = -ENOMEM;
3818 ip6_dst_ops_template.kmem_cachep =
3819 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3820 SLAB_HWCACHE_ALIGN, NULL);
3821 if (!ip6_dst_ops_template.kmem_cachep)
3822 goto out;
3824 ret = dst_entries_init(&ip6_dst_blackhole_ops);
3825 if (ret)
3826 goto out_kmem_cache;
3828 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3829 if (ret)
3830 goto out_dst_entries;
3832 ret = register_pernet_subsys(&ip6_route_net_ops);
3833 if (ret)
3834 goto out_register_inetpeer;
3836 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3838 /* Registering of the loopback is done before this portion of code,
3839 * the loopback reference in rt6_info will not be taken, do it
3840 * manually for init_net */
3841 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3842 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3843 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3844 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3845 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3846 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3847 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3848 #endif
3849 ret = fib6_init();
3850 if (ret)
3851 goto out_register_subsys;
3853 ret = xfrm6_init();
3854 if (ret)
3855 goto out_fib6_init;
3857 ret = fib6_rules_init();
3858 if (ret)
3859 goto xfrm6_init;
3861 ret = register_pernet_subsys(&ip6_route_net_late_ops);
3862 if (ret)
3863 goto fib6_rules_init;
3865 ret = -ENOBUFS;
3866 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3867 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3868 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3869 goto out_register_late_subsys;
3871 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3872 if (ret)
3873 goto out_register_late_subsys;
3875 for_each_possible_cpu(cpu) {
3876 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3878 INIT_LIST_HEAD(&ul->head);
3879 spin_lock_init(&ul->lock);
3882 out:
3883 return ret;
3885 out_register_late_subsys:
3886 unregister_pernet_subsys(&ip6_route_net_late_ops);
3887 fib6_rules_init:
3888 fib6_rules_cleanup();
3889 xfrm6_init:
3890 xfrm6_fini();
3891 out_fib6_init:
3892 fib6_gc_cleanup();
3893 out_register_subsys:
3894 unregister_pernet_subsys(&ip6_route_net_ops);
3895 out_register_inetpeer:
3896 unregister_pernet_subsys(&ipv6_inetpeer_ops);
3897 out_dst_entries:
3898 dst_entries_destroy(&ip6_dst_blackhole_ops);
3899 out_kmem_cache:
3900 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3901 goto out;
3904 void ip6_route_cleanup(void)
3906 unregister_netdevice_notifier(&ip6_route_dev_notifier);
3907 unregister_pernet_subsys(&ip6_route_net_late_ops);
3908 fib6_rules_cleanup();
3909 xfrm6_fini();
3910 fib6_gc_cleanup();
3911 unregister_pernet_subsys(&ipv6_inetpeer_ops);
3912 unregister_pernet_subsys(&ip6_route_net_ops);
3913 dst_entries_destroy(&ip6_dst_blackhole_ops);
3914 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);