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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Linux INET6 implementation
4 * FIB front-end.
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 */
9
10/* Changes:
11 *
12 * YOSHIFUJI Hideaki @USAGI
13 * reworked default router selection.
14 * - respect outgoing interface
15 * - select from (probably) reachable routers (i.e.
16 * routers in REACHABLE, STALE, DELAY or PROBE states).
17 * - always select the same router if it is (probably)
18 * reachable. otherwise, round-robin the list.
19 * Ville Nuorvala
20 * Fixed routing subtrees.
21 */
22
23#define pr_fmt(fmt) "IPv6: " fmt
24
25#include <linux/capability.h>
26#include <linux/errno.h>
27#include <linux/export.h>
28#include <linux/types.h>
29#include <linux/times.h>
30#include <linux/socket.h>
31#include <linux/sockios.h>
32#include <linux/net.h>
33#include <linux/route.h>
34#include <linux/netdevice.h>
35#include <linux/in6.h>
36#include <linux/mroute6.h>
37#include <linux/init.h>
38#include <linux/if_arp.h>
39#include <linux/proc_fs.h>
40#include <linux/seq_file.h>
41#include <linux/nsproxy.h>
42#include <linux/slab.h>
43#include <linux/jhash.h>
44#include <linux/siphash.h>
45#include <net/net_namespace.h>
46#include <net/snmp.h>
47#include <net/ipv6.h>
48#include <net/ip6_fib.h>
49#include <net/ip6_route.h>
50#include <net/ndisc.h>
51#include <net/addrconf.h>
52#include <net/tcp.h>
53#include <linux/rtnetlink.h>
54#include <net/dst.h>
55#include <net/dst_metadata.h>
56#include <net/xfrm.h>
57#include <net/netevent.h>
58#include <net/netlink.h>
59#include <net/rtnh.h>
60#include <net/lwtunnel.h>
61#include <net/ip_tunnels.h>
62#include <net/l3mdev.h>
63#include <net/ip.h>
64#include <linux/uaccess.h>
65#include <linux/btf_ids.h>
66
67#ifdef CONFIG_SYSCTL
68#include <linux/sysctl.h>
69#endif
70
71static int ip6_rt_type_to_error(u8 fib6_type);
72
73#define CREATE_TRACE_POINTS
74#include <trace/events/fib6.h>
75EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup);
76#undef CREATE_TRACE_POINTS
77
78enum rt6_nud_state {
79 RT6_NUD_FAIL_HARD = -3,
80 RT6_NUD_FAIL_PROBE = -2,
81 RT6_NUD_FAIL_DO_RR = -1,
82 RT6_NUD_SUCCEED = 1
83};
84
85INDIRECT_CALLABLE_SCOPE
86struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
87static unsigned int ip6_default_advmss(const struct dst_entry *dst);
88INDIRECT_CALLABLE_SCOPE
89unsigned int ip6_mtu(const struct dst_entry *dst);
90static void ip6_negative_advice(struct sock *sk,
91 struct dst_entry *dst);
92static void ip6_dst_destroy(struct dst_entry *);
93static void ip6_dst_ifdown(struct dst_entry *,
94 struct net_device *dev);
95static void ip6_dst_gc(struct dst_ops *ops);
96
97static int ip6_pkt_discard(struct sk_buff *skb);
98static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
99static int ip6_pkt_prohibit(struct sk_buff *skb);
100static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
101static void ip6_link_failure(struct sk_buff *skb);
102static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
103 struct sk_buff *skb, u32 mtu,
104 bool confirm_neigh);
105static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
106 struct sk_buff *skb);
107static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
108 int strict);
109static size_t rt6_nlmsg_size(struct fib6_info *f6i);
110static int rt6_fill_node(struct net *net, struct sk_buff *skb,
111 struct fib6_info *rt, struct dst_entry *dst,
112 struct in6_addr *dest, struct in6_addr *src,
113 int iif, int type, u32 portid, u32 seq,
114 unsigned int flags);
115static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
116 const struct in6_addr *daddr,
117 const struct in6_addr *saddr);
118
119#ifdef CONFIG_IPV6_ROUTE_INFO
120static struct fib6_info *rt6_add_route_info(struct net *net,
121 const struct in6_addr *prefix, int prefixlen,
122 const struct in6_addr *gwaddr,
123 struct net_device *dev,
124 unsigned int pref);
125static struct fib6_info *rt6_get_route_info(struct net *net,
126 const struct in6_addr *prefix, int prefixlen,
127 const struct in6_addr *gwaddr,
128 struct net_device *dev);
129#endif
130
131struct uncached_list {
132 spinlock_t lock;
133 struct list_head head;
134};
135
136static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
137
138void rt6_uncached_list_add(struct rt6_info *rt)
139{
140 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
141
142 rt->dst.rt_uncached_list = ul;
143
144 spin_lock_bh(&ul->lock);
145 list_add_tail(&rt->dst.rt_uncached, &ul->head);
146 spin_unlock_bh(&ul->lock);
147}
148
149void rt6_uncached_list_del(struct rt6_info *rt)
150{
151 if (!list_empty(&rt->dst.rt_uncached)) {
152 struct uncached_list *ul = rt->dst.rt_uncached_list;
153
154 spin_lock_bh(&ul->lock);
155 list_del_init(&rt->dst.rt_uncached);
156 spin_unlock_bh(&ul->lock);
157 }
158}
159
160static void rt6_uncached_list_flush_dev(struct net_device *dev)
161{
162 int cpu;
163
164 for_each_possible_cpu(cpu) {
165 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
166 struct rt6_info *rt, *safe;
167
168 if (list_empty(&ul->head))
169 continue;
170
171 spin_lock_bh(&ul->lock);
172 list_for_each_entry_safe(rt, safe, &ul->head, dst.rt_uncached) {
173 struct inet6_dev *rt_idev = rt->rt6i_idev;
174 struct net_device *rt_dev = rt->dst.dev;
175 bool handled = false;
176
177 if (rt_idev && rt_idev->dev == dev) {
178 rt->rt6i_idev = in6_dev_get(blackhole_netdev);
179 in6_dev_put(rt_idev);
180 handled = true;
181 }
182
183 if (rt_dev == dev) {
184 rt->dst.dev = blackhole_netdev;
185 netdev_ref_replace(rt_dev, blackhole_netdev,
186 &rt->dst.dev_tracker,
187 GFP_ATOMIC);
188 handled = true;
189 }
190 if (handled)
191 list_del_init(&rt->dst.rt_uncached);
192 }
193 spin_unlock_bh(&ul->lock);
194 }
195}
196
197static inline const void *choose_neigh_daddr(const struct in6_addr *p,
198 struct sk_buff *skb,
199 const void *daddr)
200{
201 if (!ipv6_addr_any(p))
202 return (const void *) p;
203 else if (skb)
204 return &ipv6_hdr(skb)->daddr;
205 return daddr;
206}
207
208struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
209 struct net_device *dev,
210 struct sk_buff *skb,
211 const void *daddr)
212{
213 struct neighbour *n;
214
215 daddr = choose_neigh_daddr(gw, skb, daddr);
216 n = __ipv6_neigh_lookup(dev, daddr);
217 if (n)
218 return n;
219
220 n = neigh_create(&nd_tbl, daddr, dev);
221 return IS_ERR(n) ? NULL : n;
222}
223
224static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst,
225 struct sk_buff *skb,
226 const void *daddr)
227{
228 const struct rt6_info *rt = dst_rt6_info(dst);
229
230 return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any),
231 dst->dev, skb, daddr);
232}
233
234static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr)
235{
236 const struct rt6_info *rt = dst_rt6_info(dst);
237 struct net_device *dev = dst->dev;
238
239 daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr);
240 if (!daddr)
241 return;
242 if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
243 return;
244 if (ipv6_addr_is_multicast((const struct in6_addr *)daddr))
245 return;
246 __ipv6_confirm_neigh(dev, daddr);
247}
248
249static struct dst_ops ip6_dst_ops_template = {
250 .family = AF_INET6,
251 .gc = ip6_dst_gc,
252 .gc_thresh = 1024,
253 .check = ip6_dst_check,
254 .default_advmss = ip6_default_advmss,
255 .mtu = ip6_mtu,
256 .cow_metrics = dst_cow_metrics_generic,
257 .destroy = ip6_dst_destroy,
258 .ifdown = ip6_dst_ifdown,
259 .negative_advice = ip6_negative_advice,
260 .link_failure = ip6_link_failure,
261 .update_pmtu = ip6_rt_update_pmtu,
262 .redirect = rt6_do_redirect,
263 .local_out = __ip6_local_out,
264 .neigh_lookup = ip6_dst_neigh_lookup,
265 .confirm_neigh = ip6_confirm_neigh,
266};
267
268static struct dst_ops ip6_dst_blackhole_ops = {
269 .family = AF_INET6,
270 .default_advmss = ip6_default_advmss,
271 .neigh_lookup = ip6_dst_neigh_lookup,
272 .check = ip6_dst_check,
273 .destroy = ip6_dst_destroy,
274 .cow_metrics = dst_cow_metrics_generic,
275 .update_pmtu = dst_blackhole_update_pmtu,
276 .redirect = dst_blackhole_redirect,
277 .mtu = dst_blackhole_mtu,
278};
279
280static const u32 ip6_template_metrics[RTAX_MAX] = {
281 [RTAX_HOPLIMIT - 1] = 0,
282};
283
284static const struct fib6_info fib6_null_entry_template = {
285 .fib6_flags = (RTF_REJECT | RTF_NONEXTHOP),
286 .fib6_protocol = RTPROT_KERNEL,
287 .fib6_metric = ~(u32)0,
288 .fib6_ref = REFCOUNT_INIT(1),
289 .fib6_type = RTN_UNREACHABLE,
290 .fib6_metrics = (struct dst_metrics *)&dst_default_metrics,
291};
292
293static const struct rt6_info ip6_null_entry_template = {
294 .dst = {
295 .__rcuref = RCUREF_INIT(1),
296 .__use = 1,
297 .obsolete = DST_OBSOLETE_FORCE_CHK,
298 .error = -ENETUNREACH,
299 .input = ip6_pkt_discard,
300 .output = ip6_pkt_discard_out,
301 },
302 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
303};
304
305#ifdef CONFIG_IPV6_MULTIPLE_TABLES
306
307static const struct rt6_info ip6_prohibit_entry_template = {
308 .dst = {
309 .__rcuref = RCUREF_INIT(1),
310 .__use = 1,
311 .obsolete = DST_OBSOLETE_FORCE_CHK,
312 .error = -EACCES,
313 .input = ip6_pkt_prohibit,
314 .output = ip6_pkt_prohibit_out,
315 },
316 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
317};
318
319static const struct rt6_info ip6_blk_hole_entry_template = {
320 .dst = {
321 .__rcuref = RCUREF_INIT(1),
322 .__use = 1,
323 .obsolete = DST_OBSOLETE_FORCE_CHK,
324 .error = -EINVAL,
325 .input = dst_discard,
326 .output = dst_discard_out,
327 },
328 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
329};
330
331#endif
332
333static void rt6_info_init(struct rt6_info *rt)
334{
335 memset_after(rt, 0, dst);
336}
337
338/* allocate dst with ip6_dst_ops */
339struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
340 int flags)
341{
342 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
343 DST_OBSOLETE_FORCE_CHK, flags);
344
345 if (rt) {
346 rt6_info_init(rt);
347 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
348 }
349
350 return rt;
351}
352EXPORT_SYMBOL(ip6_dst_alloc);
353
354static void ip6_dst_destroy(struct dst_entry *dst)
355{
356 struct rt6_info *rt = dst_rt6_info(dst);
357 struct fib6_info *from;
358 struct inet6_dev *idev;
359
360 ip_dst_metrics_put(dst);
361 rt6_uncached_list_del(rt);
362
363 idev = rt->rt6i_idev;
364 if (idev) {
365 rt->rt6i_idev = NULL;
366 in6_dev_put(idev);
367 }
368
369 from = unrcu_pointer(xchg(&rt->from, NULL));
370 fib6_info_release(from);
371}
372
373static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
374{
375 struct rt6_info *rt = dst_rt6_info(dst);
376 struct inet6_dev *idev = rt->rt6i_idev;
377 struct fib6_info *from;
378
379 if (idev && idev->dev != blackhole_netdev) {
380 struct inet6_dev *blackhole_idev = in6_dev_get(blackhole_netdev);
381
382 if (blackhole_idev) {
383 rt->rt6i_idev = blackhole_idev;
384 in6_dev_put(idev);
385 }
386 }
387 from = unrcu_pointer(xchg(&rt->from, NULL));
388 fib6_info_release(from);
389}
390
391static bool __rt6_check_expired(const struct rt6_info *rt)
392{
393 if (rt->rt6i_flags & RTF_EXPIRES)
394 return time_after(jiffies, rt->dst.expires);
395 else
396 return false;
397}
398
399static bool rt6_check_expired(const struct rt6_info *rt)
400{
401 struct fib6_info *from;
402
403 from = rcu_dereference(rt->from);
404
405 if (rt->rt6i_flags & RTF_EXPIRES) {
406 if (time_after(jiffies, rt->dst.expires))
407 return true;
408 } else if (from) {
409 return rt->dst.obsolete != DST_OBSOLETE_FORCE_CHK ||
410 fib6_check_expired(from);
411 }
412 return false;
413}
414
415void fib6_select_path(const struct net *net, struct fib6_result *res,
416 struct flowi6 *fl6, int oif, bool have_oif_match,
417 const struct sk_buff *skb, int strict)
418{
419 struct fib6_info *match = res->f6i;
420 struct fib6_info *sibling;
421
422 if (!match->nh && (!match->fib6_nsiblings || have_oif_match))
423 goto out;
424
425 if (match->nh && have_oif_match && res->nh)
426 return;
427
428 if (skb)
429 IP6CB(skb)->flags |= IP6SKB_MULTIPATH;
430
431 /* We might have already computed the hash for ICMPv6 errors. In such
432 * case it will always be non-zero. Otherwise now is the time to do it.
433 */
434 if (!fl6->mp_hash &&
435 (!match->nh || nexthop_is_multipath(match->nh)))
436 fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL);
437
438 if (unlikely(match->nh)) {
439 nexthop_path_fib6_result(res, fl6->mp_hash);
440 return;
441 }
442
443 if (fl6->mp_hash <= atomic_read(&match->fib6_nh->fib_nh_upper_bound))
444 goto out;
445
446 list_for_each_entry_rcu(sibling, &match->fib6_siblings,
447 fib6_siblings) {
448 const struct fib6_nh *nh = sibling->fib6_nh;
449 int nh_upper_bound;
450
451 nh_upper_bound = atomic_read(&nh->fib_nh_upper_bound);
452 if (fl6->mp_hash > nh_upper_bound)
453 continue;
454 if (rt6_score_route(nh, sibling->fib6_flags, oif, strict) < 0)
455 break;
456 match = sibling;
457 break;
458 }
459
460out:
461 res->f6i = match;
462 res->nh = match->fib6_nh;
463}
464
465/*
466 * Route lookup. rcu_read_lock() should be held.
467 */
468
469static bool __rt6_device_match(struct net *net, const struct fib6_nh *nh,
470 const struct in6_addr *saddr, int oif, int flags)
471{
472 const struct net_device *dev;
473
474 if (nh->fib_nh_flags & RTNH_F_DEAD)
475 return false;
476
477 dev = nh->fib_nh_dev;
478 if (oif) {
479 if (dev->ifindex == oif)
480 return true;
481 } else {
482 if (ipv6_chk_addr(net, saddr, dev,
483 flags & RT6_LOOKUP_F_IFACE))
484 return true;
485 }
486
487 return false;
488}
489
490struct fib6_nh_dm_arg {
491 struct net *net;
492 const struct in6_addr *saddr;
493 int oif;
494 int flags;
495 struct fib6_nh *nh;
496};
497
498static int __rt6_nh_dev_match(struct fib6_nh *nh, void *_arg)
499{
500 struct fib6_nh_dm_arg *arg = _arg;
501
502 arg->nh = nh;
503 return __rt6_device_match(arg->net, nh, arg->saddr, arg->oif,
504 arg->flags);
505}
506
507/* returns fib6_nh from nexthop or NULL */
508static struct fib6_nh *rt6_nh_dev_match(struct net *net, struct nexthop *nh,
509 struct fib6_result *res,
510 const struct in6_addr *saddr,
511 int oif, int flags)
512{
513 struct fib6_nh_dm_arg arg = {
514 .net = net,
515 .saddr = saddr,
516 .oif = oif,
517 .flags = flags,
518 };
519
520 if (nexthop_is_blackhole(nh))
521 return NULL;
522
523 if (nexthop_for_each_fib6_nh(nh, __rt6_nh_dev_match, &arg))
524 return arg.nh;
525
526 return NULL;
527}
528
529static void rt6_device_match(struct net *net, struct fib6_result *res,
530 const struct in6_addr *saddr, int oif, int flags)
531{
532 struct fib6_info *f6i = res->f6i;
533 struct fib6_info *spf6i;
534 struct fib6_nh *nh;
535
536 if (!oif && ipv6_addr_any(saddr)) {
537 if (unlikely(f6i->nh)) {
538 nh = nexthop_fib6_nh(f6i->nh);
539 if (nexthop_is_blackhole(f6i->nh))
540 goto out_blackhole;
541 } else {
542 nh = f6i->fib6_nh;
543 }
544 if (!(nh->fib_nh_flags & RTNH_F_DEAD))
545 goto out;
546 }
547
548 for (spf6i = f6i; spf6i; spf6i = rcu_dereference(spf6i->fib6_next)) {
549 bool matched = false;
550
551 if (unlikely(spf6i->nh)) {
552 nh = rt6_nh_dev_match(net, spf6i->nh, res, saddr,
553 oif, flags);
554 if (nh)
555 matched = true;
556 } else {
557 nh = spf6i->fib6_nh;
558 if (__rt6_device_match(net, nh, saddr, oif, flags))
559 matched = true;
560 }
561 if (matched) {
562 res->f6i = spf6i;
563 goto out;
564 }
565 }
566
567 if (oif && flags & RT6_LOOKUP_F_IFACE) {
568 res->f6i = net->ipv6.fib6_null_entry;
569 nh = res->f6i->fib6_nh;
570 goto out;
571 }
572
573 if (unlikely(f6i->nh)) {
574 nh = nexthop_fib6_nh(f6i->nh);
575 if (nexthop_is_blackhole(f6i->nh))
576 goto out_blackhole;
577 } else {
578 nh = f6i->fib6_nh;
579 }
580
581 if (nh->fib_nh_flags & RTNH_F_DEAD) {
582 res->f6i = net->ipv6.fib6_null_entry;
583 nh = res->f6i->fib6_nh;
584 }
585out:
586 res->nh = nh;
587 res->fib6_type = res->f6i->fib6_type;
588 res->fib6_flags = res->f6i->fib6_flags;
589 return;
590
591out_blackhole:
592 res->fib6_flags |= RTF_REJECT;
593 res->fib6_type = RTN_BLACKHOLE;
594 res->nh = nh;
595}
596
597#ifdef CONFIG_IPV6_ROUTER_PREF
598struct __rt6_probe_work {
599 struct work_struct work;
600 struct in6_addr target;
601 struct net_device *dev;
602 netdevice_tracker dev_tracker;
603};
604
605static void rt6_probe_deferred(struct work_struct *w)
606{
607 struct in6_addr mcaddr;
608 struct __rt6_probe_work *work =
609 container_of(w, struct __rt6_probe_work, work);
610
611 addrconf_addr_solict_mult(&work->target, &mcaddr);
612 ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
613 netdev_put(work->dev, &work->dev_tracker);
614 kfree(work);
615}
616
617static void rt6_probe(struct fib6_nh *fib6_nh)
618{
619 struct __rt6_probe_work *work = NULL;
620 const struct in6_addr *nh_gw;
621 unsigned long last_probe;
622 struct neighbour *neigh;
623 struct net_device *dev;
624 struct inet6_dev *idev;
625
626 /*
627 * Okay, this does not seem to be appropriate
628 * for now, however, we need to check if it
629 * is really so; aka Router Reachability Probing.
630 *
631 * Router Reachability Probe MUST be rate-limited
632 * to no more than one per minute.
633 */
634 if (!fib6_nh->fib_nh_gw_family)
635 return;
636
637 nh_gw = &fib6_nh->fib_nh_gw6;
638 dev = fib6_nh->fib_nh_dev;
639 rcu_read_lock();
640 last_probe = READ_ONCE(fib6_nh->last_probe);
641 idev = __in6_dev_get(dev);
642 if (!idev)
643 goto out;
644 neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
645 if (neigh) {
646 if (READ_ONCE(neigh->nud_state) & NUD_VALID)
647 goto out;
648
649 write_lock_bh(&neigh->lock);
650 if (!(neigh->nud_state & NUD_VALID) &&
651 time_after(jiffies,
652 neigh->updated +
653 READ_ONCE(idev->cnf.rtr_probe_interval))) {
654 work = kmalloc(sizeof(*work), GFP_ATOMIC);
655 if (work)
656 __neigh_set_probe_once(neigh);
657 }
658 write_unlock_bh(&neigh->lock);
659 } else if (time_after(jiffies, last_probe +
660 READ_ONCE(idev->cnf.rtr_probe_interval))) {
661 work = kmalloc(sizeof(*work), GFP_ATOMIC);
662 }
663
664 if (!work || cmpxchg(&fib6_nh->last_probe,
665 last_probe, jiffies) != last_probe) {
666 kfree(work);
667 } else {
668 INIT_WORK(&work->work, rt6_probe_deferred);
669 work->target = *nh_gw;
670 netdev_hold(dev, &work->dev_tracker, GFP_ATOMIC);
671 work->dev = dev;
672 schedule_work(&work->work);
673 }
674
675out:
676 rcu_read_unlock();
677}
678#else
679static inline void rt6_probe(struct fib6_nh *fib6_nh)
680{
681}
682#endif
683
684/*
685 * Default Router Selection (RFC 2461 6.3.6)
686 */
687static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
688{
689 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
690 struct neighbour *neigh;
691
692 rcu_read_lock();
693 neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev,
694 &fib6_nh->fib_nh_gw6);
695 if (neigh) {
696 u8 nud_state = READ_ONCE(neigh->nud_state);
697
698 if (nud_state & NUD_VALID)
699 ret = RT6_NUD_SUCCEED;
700#ifdef CONFIG_IPV6_ROUTER_PREF
701 else if (!(nud_state & NUD_FAILED))
702 ret = RT6_NUD_SUCCEED;
703 else
704 ret = RT6_NUD_FAIL_PROBE;
705#endif
706 } else {
707 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
708 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
709 }
710 rcu_read_unlock();
711
712 return ret;
713}
714
715static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
716 int strict)
717{
718 int m = 0;
719
720 if (!oif || nh->fib_nh_dev->ifindex == oif)
721 m = 2;
722
723 if (!m && (strict & RT6_LOOKUP_F_IFACE))
724 return RT6_NUD_FAIL_HARD;
725#ifdef CONFIG_IPV6_ROUTER_PREF
726 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(fib6_flags)) << 2;
727#endif
728 if ((strict & RT6_LOOKUP_F_REACHABLE) &&
729 !(fib6_flags & RTF_NONEXTHOP) && nh->fib_nh_gw_family) {
730 int n = rt6_check_neigh(nh);
731 if (n < 0)
732 return n;
733 }
734 return m;
735}
736
737static bool find_match(struct fib6_nh *nh, u32 fib6_flags,
738 int oif, int strict, int *mpri, bool *do_rr)
739{
740 bool match_do_rr = false;
741 bool rc = false;
742 int m;
743
744 if (nh->fib_nh_flags & RTNH_F_DEAD)
745 goto out;
746
747 if (ip6_ignore_linkdown(nh->fib_nh_dev) &&
748 nh->fib_nh_flags & RTNH_F_LINKDOWN &&
749 !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
750 goto out;
751
752 m = rt6_score_route(nh, fib6_flags, oif, strict);
753 if (m == RT6_NUD_FAIL_DO_RR) {
754 match_do_rr = true;
755 m = 0; /* lowest valid score */
756 } else if (m == RT6_NUD_FAIL_HARD) {
757 goto out;
758 }
759
760 if (strict & RT6_LOOKUP_F_REACHABLE)
761 rt6_probe(nh);
762
763 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
764 if (m > *mpri) {
765 *do_rr = match_do_rr;
766 *mpri = m;
767 rc = true;
768 }
769out:
770 return rc;
771}
772
773struct fib6_nh_frl_arg {
774 u32 flags;
775 int oif;
776 int strict;
777 int *mpri;
778 bool *do_rr;
779 struct fib6_nh *nh;
780};
781
782static int rt6_nh_find_match(struct fib6_nh *nh, void *_arg)
783{
784 struct fib6_nh_frl_arg *arg = _arg;
785
786 arg->nh = nh;
787 return find_match(nh, arg->flags, arg->oif, arg->strict,
788 arg->mpri, arg->do_rr);
789}
790
791static void __find_rr_leaf(struct fib6_info *f6i_start,
792 struct fib6_info *nomatch, u32 metric,
793 struct fib6_result *res, struct fib6_info **cont,
794 int oif, int strict, bool *do_rr, int *mpri)
795{
796 struct fib6_info *f6i;
797
798 for (f6i = f6i_start;
799 f6i && f6i != nomatch;
800 f6i = rcu_dereference(f6i->fib6_next)) {
801 bool matched = false;
802 struct fib6_nh *nh;
803
804 if (cont && f6i->fib6_metric != metric) {
805 *cont = f6i;
806 return;
807 }
808
809 if (fib6_check_expired(f6i))
810 continue;
811
812 if (unlikely(f6i->nh)) {
813 struct fib6_nh_frl_arg arg = {
814 .flags = f6i->fib6_flags,
815 .oif = oif,
816 .strict = strict,
817 .mpri = mpri,
818 .do_rr = do_rr
819 };
820
821 if (nexthop_is_blackhole(f6i->nh)) {
822 res->fib6_flags = RTF_REJECT;
823 res->fib6_type = RTN_BLACKHOLE;
824 res->f6i = f6i;
825 res->nh = nexthop_fib6_nh(f6i->nh);
826 return;
827 }
828 if (nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_find_match,
829 &arg)) {
830 matched = true;
831 nh = arg.nh;
832 }
833 } else {
834 nh = f6i->fib6_nh;
835 if (find_match(nh, f6i->fib6_flags, oif, strict,
836 mpri, do_rr))
837 matched = true;
838 }
839 if (matched) {
840 res->f6i = f6i;
841 res->nh = nh;
842 res->fib6_flags = f6i->fib6_flags;
843 res->fib6_type = f6i->fib6_type;
844 }
845 }
846}
847
848static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf,
849 struct fib6_info *rr_head, int oif, int strict,
850 bool *do_rr, struct fib6_result *res)
851{
852 u32 metric = rr_head->fib6_metric;
853 struct fib6_info *cont = NULL;
854 int mpri = -1;
855
856 __find_rr_leaf(rr_head, NULL, metric, res, &cont,
857 oif, strict, do_rr, &mpri);
858
859 __find_rr_leaf(leaf, rr_head, metric, res, &cont,
860 oif, strict, do_rr, &mpri);
861
862 if (res->f6i || !cont)
863 return;
864
865 __find_rr_leaf(cont, NULL, metric, res, NULL,
866 oif, strict, do_rr, &mpri);
867}
868
869static void rt6_select(struct net *net, struct fib6_node *fn, int oif,
870 struct fib6_result *res, int strict)
871{
872 struct fib6_info *leaf = rcu_dereference(fn->leaf);
873 struct fib6_info *rt0;
874 bool do_rr = false;
875 int key_plen;
876
877 /* make sure this function or its helpers sets f6i */
878 res->f6i = NULL;
879
880 if (!leaf || leaf == net->ipv6.fib6_null_entry)
881 goto out;
882
883 rt0 = rcu_dereference(fn->rr_ptr);
884 if (!rt0)
885 rt0 = leaf;
886
887 /* Double check to make sure fn is not an intermediate node
888 * and fn->leaf does not points to its child's leaf
889 * (This might happen if all routes under fn are deleted from
890 * the tree and fib6_repair_tree() is called on the node.)
891 */
892 key_plen = rt0->fib6_dst.plen;
893#ifdef CONFIG_IPV6_SUBTREES
894 if (rt0->fib6_src.plen)
895 key_plen = rt0->fib6_src.plen;
896#endif
897 if (fn->fn_bit != key_plen)
898 goto out;
899
900 find_rr_leaf(fn, leaf, rt0, oif, strict, &do_rr, res);
901 if (do_rr) {
902 struct fib6_info *next = rcu_dereference(rt0->fib6_next);
903
904 /* no entries matched; do round-robin */
905 if (!next || next->fib6_metric != rt0->fib6_metric)
906 next = leaf;
907
908 if (next != rt0) {
909 spin_lock_bh(&leaf->fib6_table->tb6_lock);
910 /* make sure next is not being deleted from the tree */
911 if (next->fib6_node)
912 rcu_assign_pointer(fn->rr_ptr, next);
913 spin_unlock_bh(&leaf->fib6_table->tb6_lock);
914 }
915 }
916
917out:
918 if (!res->f6i) {
919 res->f6i = net->ipv6.fib6_null_entry;
920 res->nh = res->f6i->fib6_nh;
921 res->fib6_flags = res->f6i->fib6_flags;
922 res->fib6_type = res->f6i->fib6_type;
923 }
924}
925
926static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res)
927{
928 return (res->f6i->fib6_flags & RTF_NONEXTHOP) ||
929 res->nh->fib_nh_gw_family;
930}
931
932#ifdef CONFIG_IPV6_ROUTE_INFO
933int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
934 const struct in6_addr *gwaddr)
935{
936 struct net *net = dev_net(dev);
937 struct route_info *rinfo = (struct route_info *) opt;
938 struct in6_addr prefix_buf, *prefix;
939 struct fib6_table *table;
940 unsigned int pref;
941 unsigned long lifetime;
942 struct fib6_info *rt;
943
944 if (len < sizeof(struct route_info)) {
945 return -EINVAL;
946 }
947
948 /* Sanity check for prefix_len and length */
949 if (rinfo->length > 3) {
950 return -EINVAL;
951 } else if (rinfo->prefix_len > 128) {
952 return -EINVAL;
953 } else if (rinfo->prefix_len > 64) {
954 if (rinfo->length < 2) {
955 return -EINVAL;
956 }
957 } else if (rinfo->prefix_len > 0) {
958 if (rinfo->length < 1) {
959 return -EINVAL;
960 }
961 }
962
963 pref = rinfo->route_pref;
964 if (pref == ICMPV6_ROUTER_PREF_INVALID)
965 return -EINVAL;
966
967 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
968
969 if (rinfo->length == 3)
970 prefix = (struct in6_addr *)rinfo->prefix;
971 else {
972 /* this function is safe */
973 ipv6_addr_prefix(&prefix_buf,
974 (struct in6_addr *)rinfo->prefix,
975 rinfo->prefix_len);
976 prefix = &prefix_buf;
977 }
978
979 if (rinfo->prefix_len == 0)
980 rt = rt6_get_dflt_router(net, gwaddr, dev);
981 else
982 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
983 gwaddr, dev);
984
985 if (rt && !lifetime) {
986 ip6_del_rt(net, rt, false);
987 rt = NULL;
988 }
989
990 if (!rt && lifetime)
991 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
992 dev, pref);
993 else if (rt)
994 rt->fib6_flags = RTF_ROUTEINFO |
995 (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
996
997 if (rt) {
998 table = rt->fib6_table;
999 spin_lock_bh(&table->tb6_lock);
1000
1001 if (!addrconf_finite_timeout(lifetime)) {
1002 fib6_clean_expires(rt);
1003 fib6_remove_gc_list(rt);
1004 } else {
1005 fib6_set_expires(rt, jiffies + HZ * lifetime);
1006 fib6_add_gc_list(rt);
1007 }
1008
1009 spin_unlock_bh(&table->tb6_lock);
1010
1011 fib6_info_release(rt);
1012 }
1013 return 0;
1014}
1015#endif
1016
1017/*
1018 * Misc support functions
1019 */
1020
1021/* called with rcu_lock held */
1022static struct net_device *ip6_rt_get_dev_rcu(const struct fib6_result *res)
1023{
1024 struct net_device *dev = res->nh->fib_nh_dev;
1025
1026 if (res->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) {
1027 /* for copies of local routes, dst->dev needs to be the
1028 * device if it is a master device, the master device if
1029 * device is enslaved, and the loopback as the default
1030 */
1031 if (netif_is_l3_slave(dev) &&
1032 !rt6_need_strict(&res->f6i->fib6_dst.addr))
1033 dev = l3mdev_master_dev_rcu(dev);
1034 else if (!netif_is_l3_master(dev))
1035 dev = dev_net(dev)->loopback_dev;
1036 /* last case is netif_is_l3_master(dev) is true in which
1037 * case we want dev returned to be dev
1038 */
1039 }
1040
1041 return dev;
1042}
1043
1044static const int fib6_prop[RTN_MAX + 1] = {
1045 [RTN_UNSPEC] = 0,
1046 [RTN_UNICAST] = 0,
1047 [RTN_LOCAL] = 0,
1048 [RTN_BROADCAST] = 0,
1049 [RTN_ANYCAST] = 0,
1050 [RTN_MULTICAST] = 0,
1051 [RTN_BLACKHOLE] = -EINVAL,
1052 [RTN_UNREACHABLE] = -EHOSTUNREACH,
1053 [RTN_PROHIBIT] = -EACCES,
1054 [RTN_THROW] = -EAGAIN,
1055 [RTN_NAT] = -EINVAL,
1056 [RTN_XRESOLVE] = -EINVAL,
1057};
1058
1059static int ip6_rt_type_to_error(u8 fib6_type)
1060{
1061 return fib6_prop[fib6_type];
1062}
1063
1064static unsigned short fib6_info_dst_flags(struct fib6_info *rt)
1065{
1066 unsigned short flags = 0;
1067
1068 if (rt->dst_nocount)
1069 flags |= DST_NOCOUNT;
1070 if (rt->dst_nopolicy)
1071 flags |= DST_NOPOLICY;
1072
1073 return flags;
1074}
1075
1076static void ip6_rt_init_dst_reject(struct rt6_info *rt, u8 fib6_type)
1077{
1078 rt->dst.error = ip6_rt_type_to_error(fib6_type);
1079
1080 switch (fib6_type) {
1081 case RTN_BLACKHOLE:
1082 rt->dst.output = dst_discard_out;
1083 rt->dst.input = dst_discard;
1084 break;
1085 case RTN_PROHIBIT:
1086 rt->dst.output = ip6_pkt_prohibit_out;
1087 rt->dst.input = ip6_pkt_prohibit;
1088 break;
1089 case RTN_THROW:
1090 case RTN_UNREACHABLE:
1091 default:
1092 rt->dst.output = ip6_pkt_discard_out;
1093 rt->dst.input = ip6_pkt_discard;
1094 break;
1095 }
1096}
1097
1098static void ip6_rt_init_dst(struct rt6_info *rt, const struct fib6_result *res)
1099{
1100 struct fib6_info *f6i = res->f6i;
1101
1102 if (res->fib6_flags & RTF_REJECT) {
1103 ip6_rt_init_dst_reject(rt, res->fib6_type);
1104 return;
1105 }
1106
1107 rt->dst.error = 0;
1108 rt->dst.output = ip6_output;
1109
1110 if (res->fib6_type == RTN_LOCAL || res->fib6_type == RTN_ANYCAST) {
1111 rt->dst.input = ip6_input;
1112 } else if (ipv6_addr_type(&f6i->fib6_dst.addr) & IPV6_ADDR_MULTICAST) {
1113 rt->dst.input = ip6_mc_input;
1114 } else {
1115 rt->dst.input = ip6_forward;
1116 }
1117
1118 if (res->nh->fib_nh_lws) {
1119 rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws);
1120 lwtunnel_set_redirect(&rt->dst);
1121 }
1122
1123 rt->dst.lastuse = jiffies;
1124}
1125
1126/* Caller must already hold reference to @from */
1127static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
1128{
1129 rt->rt6i_flags &= ~RTF_EXPIRES;
1130 rcu_assign_pointer(rt->from, from);
1131 ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
1132}
1133
1134/* Caller must already hold reference to f6i in result */
1135static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res)
1136{
1137 const struct fib6_nh *nh = res->nh;
1138 const struct net_device *dev = nh->fib_nh_dev;
1139 struct fib6_info *f6i = res->f6i;
1140
1141 ip6_rt_init_dst(rt, res);
1142
1143 rt->rt6i_dst = f6i->fib6_dst;
1144 rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
1145 rt->rt6i_flags = res->fib6_flags;
1146 if (nh->fib_nh_gw_family) {
1147 rt->rt6i_gateway = nh->fib_nh_gw6;
1148 rt->rt6i_flags |= RTF_GATEWAY;
1149 }
1150 rt6_set_from(rt, f6i);
1151#ifdef CONFIG_IPV6_SUBTREES
1152 rt->rt6i_src = f6i->fib6_src;
1153#endif
1154}
1155
1156static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
1157 struct in6_addr *saddr)
1158{
1159 struct fib6_node *pn, *sn;
1160 while (1) {
1161 if (fn->fn_flags & RTN_TL_ROOT)
1162 return NULL;
1163 pn = rcu_dereference(fn->parent);
1164 sn = FIB6_SUBTREE(pn);
1165 if (sn && sn != fn)
1166 fn = fib6_node_lookup(sn, NULL, saddr);
1167 else
1168 fn = pn;
1169 if (fn->fn_flags & RTN_RTINFO)
1170 return fn;
1171 }
1172}
1173
1174static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
1175{
1176 struct rt6_info *rt = *prt;
1177
1178 if (dst_hold_safe(&rt->dst))
1179 return true;
1180 if (net) {
1181 rt = net->ipv6.ip6_null_entry;
1182 dst_hold(&rt->dst);
1183 } else {
1184 rt = NULL;
1185 }
1186 *prt = rt;
1187 return false;
1188}
1189
1190/* called with rcu_lock held */
1191static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res)
1192{
1193 struct net_device *dev = res->nh->fib_nh_dev;
1194 struct fib6_info *f6i = res->f6i;
1195 unsigned short flags;
1196 struct rt6_info *nrt;
1197
1198 if (!fib6_info_hold_safe(f6i))
1199 goto fallback;
1200
1201 flags = fib6_info_dst_flags(f6i);
1202 nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
1203 if (!nrt) {
1204 fib6_info_release(f6i);
1205 goto fallback;
1206 }
1207
1208 ip6_rt_copy_init(nrt, res);
1209 return nrt;
1210
1211fallback:
1212 nrt = dev_net(dev)->ipv6.ip6_null_entry;
1213 dst_hold(&nrt->dst);
1214 return nrt;
1215}
1216
1217INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_lookup(struct net *net,
1218 struct fib6_table *table,
1219 struct flowi6 *fl6,
1220 const struct sk_buff *skb,
1221 int flags)
1222{
1223 struct fib6_result res = {};
1224 struct fib6_node *fn;
1225 struct rt6_info *rt;
1226
1227 rcu_read_lock();
1228 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1229restart:
1230 res.f6i = rcu_dereference(fn->leaf);
1231 if (!res.f6i)
1232 res.f6i = net->ipv6.fib6_null_entry;
1233 else
1234 rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif,
1235 flags);
1236
1237 if (res.f6i == net->ipv6.fib6_null_entry) {
1238 fn = fib6_backtrack(fn, &fl6->saddr);
1239 if (fn)
1240 goto restart;
1241
1242 rt = net->ipv6.ip6_null_entry;
1243 dst_hold(&rt->dst);
1244 goto out;
1245 } else if (res.fib6_flags & RTF_REJECT) {
1246 goto do_create;
1247 }
1248
1249 fib6_select_path(net, &res, fl6, fl6->flowi6_oif,
1250 fl6->flowi6_oif != 0, skb, flags);
1251
1252 /* Search through exception table */
1253 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
1254 if (rt) {
1255 if (ip6_hold_safe(net, &rt))
1256 dst_use_noref(&rt->dst, jiffies);
1257 } else {
1258do_create:
1259 rt = ip6_create_rt_rcu(&res);
1260 }
1261
1262out:
1263 trace_fib6_table_lookup(net, &res, table, fl6);
1264
1265 rcu_read_unlock();
1266
1267 return rt;
1268}
1269
1270struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
1271 const struct sk_buff *skb, int flags)
1272{
1273 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup);
1274}
1275EXPORT_SYMBOL_GPL(ip6_route_lookup);
1276
1277struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
1278 const struct in6_addr *saddr, int oif,
1279 const struct sk_buff *skb, int strict)
1280{
1281 struct flowi6 fl6 = {
1282 .flowi6_oif = oif,
1283 .daddr = *daddr,
1284 };
1285 struct dst_entry *dst;
1286 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
1287
1288 if (saddr) {
1289 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
1290 flags |= RT6_LOOKUP_F_HAS_SADDR;
1291 }
1292
1293 dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
1294 if (dst->error == 0)
1295 return dst_rt6_info(dst);
1296
1297 dst_release(dst);
1298
1299 return NULL;
1300}
1301EXPORT_SYMBOL(rt6_lookup);
1302
1303/* ip6_ins_rt is called with FREE table->tb6_lock.
1304 * It takes new route entry, the addition fails by any reason the
1305 * route is released.
1306 * Caller must hold dst before calling it.
1307 */
1308
1309static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info,
1310 struct netlink_ext_ack *extack)
1311{
1312 int err;
1313 struct fib6_table *table;
1314
1315 table = rt->fib6_table;
1316 spin_lock_bh(&table->tb6_lock);
1317 err = fib6_add(&table->tb6_root, rt, info, extack);
1318 spin_unlock_bh(&table->tb6_lock);
1319
1320 return err;
1321}
1322
1323int ip6_ins_rt(struct net *net, struct fib6_info *rt)
1324{
1325 struct nl_info info = { .nl_net = net, };
1326
1327 return __ip6_ins_rt(rt, &info, NULL);
1328}
1329
1330static struct rt6_info *ip6_rt_cache_alloc(const struct fib6_result *res,
1331 const struct in6_addr *daddr,
1332 const struct in6_addr *saddr)
1333{
1334 struct fib6_info *f6i = res->f6i;
1335 struct net_device *dev;
1336 struct rt6_info *rt;
1337
1338 /*
1339 * Clone the route.
1340 */
1341
1342 if (!fib6_info_hold_safe(f6i))
1343 return NULL;
1344
1345 dev = ip6_rt_get_dev_rcu(res);
1346 rt = ip6_dst_alloc(dev_net(dev), dev, 0);
1347 if (!rt) {
1348 fib6_info_release(f6i);
1349 return NULL;
1350 }
1351
1352 ip6_rt_copy_init(rt, res);
1353 rt->rt6i_flags |= RTF_CACHE;
1354 rt->rt6i_dst.addr = *daddr;
1355 rt->rt6i_dst.plen = 128;
1356
1357 if (!rt6_is_gw_or_nonexthop(res)) {
1358 if (f6i->fib6_dst.plen != 128 &&
1359 ipv6_addr_equal(&f6i->fib6_dst.addr, daddr))
1360 rt->rt6i_flags |= RTF_ANYCAST;
1361#ifdef CONFIG_IPV6_SUBTREES
1362 if (rt->rt6i_src.plen && saddr) {
1363 rt->rt6i_src.addr = *saddr;
1364 rt->rt6i_src.plen = 128;
1365 }
1366#endif
1367 }
1368
1369 return rt;
1370}
1371
1372static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res)
1373{
1374 struct fib6_info *f6i = res->f6i;
1375 unsigned short flags = fib6_info_dst_flags(f6i);
1376 struct net_device *dev;
1377 struct rt6_info *pcpu_rt;
1378
1379 if (!fib6_info_hold_safe(f6i))
1380 return NULL;
1381
1382 rcu_read_lock();
1383 dev = ip6_rt_get_dev_rcu(res);
1384 pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags | DST_NOCOUNT);
1385 rcu_read_unlock();
1386 if (!pcpu_rt) {
1387 fib6_info_release(f6i);
1388 return NULL;
1389 }
1390 ip6_rt_copy_init(pcpu_rt, res);
1391 pcpu_rt->rt6i_flags |= RTF_PCPU;
1392
1393 if (f6i->nh)
1394 pcpu_rt->sernum = rt_genid_ipv6(dev_net(dev));
1395
1396 return pcpu_rt;
1397}
1398
1399static bool rt6_is_valid(const struct rt6_info *rt6)
1400{
1401 return rt6->sernum == rt_genid_ipv6(dev_net(rt6->dst.dev));
1402}
1403
1404/* It should be called with rcu_read_lock() acquired */
1405static struct rt6_info *rt6_get_pcpu_route(const struct fib6_result *res)
1406{
1407 struct rt6_info *pcpu_rt;
1408
1409 pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu);
1410
1411 if (pcpu_rt && pcpu_rt->sernum && !rt6_is_valid(pcpu_rt)) {
1412 struct rt6_info *prev, **p;
1413
1414 p = this_cpu_ptr(res->nh->rt6i_pcpu);
1415 /* Paired with READ_ONCE() in __fib6_drop_pcpu_from() */
1416 prev = xchg(p, NULL);
1417 if (prev) {
1418 dst_dev_put(&prev->dst);
1419 dst_release(&prev->dst);
1420 }
1421
1422 pcpu_rt = NULL;
1423 }
1424
1425 return pcpu_rt;
1426}
1427
1428static struct rt6_info *rt6_make_pcpu_route(struct net *net,
1429 const struct fib6_result *res)
1430{
1431 struct rt6_info *pcpu_rt, *prev, **p;
1432
1433 pcpu_rt = ip6_rt_pcpu_alloc(res);
1434 if (!pcpu_rt)
1435 return NULL;
1436
1437 p = this_cpu_ptr(res->nh->rt6i_pcpu);
1438 prev = cmpxchg(p, NULL, pcpu_rt);
1439 BUG_ON(prev);
1440
1441 if (res->f6i->fib6_destroying) {
1442 struct fib6_info *from;
1443
1444 from = unrcu_pointer(xchg(&pcpu_rt->from, NULL));
1445 fib6_info_release(from);
1446 }
1447
1448 return pcpu_rt;
1449}
1450
1451/* exception hash table implementation
1452 */
1453static DEFINE_SPINLOCK(rt6_exception_lock);
1454
1455/* Remove rt6_ex from hash table and free the memory
1456 * Caller must hold rt6_exception_lock
1457 */
1458static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
1459 struct rt6_exception *rt6_ex)
1460{
1461 struct net *net;
1462
1463 if (!bucket || !rt6_ex)
1464 return;
1465
1466 net = dev_net(rt6_ex->rt6i->dst.dev);
1467 net->ipv6.rt6_stats->fib_rt_cache--;
1468
1469 /* purge completely the exception to allow releasing the held resources:
1470 * some [sk] cache may keep the dst around for unlimited time
1471 */
1472 dst_dev_put(&rt6_ex->rt6i->dst);
1473
1474 hlist_del_rcu(&rt6_ex->hlist);
1475 dst_release(&rt6_ex->rt6i->dst);
1476 kfree_rcu(rt6_ex, rcu);
1477 WARN_ON_ONCE(!bucket->depth);
1478 bucket->depth--;
1479}
1480
1481/* Remove oldest rt6_ex in bucket and free the memory
1482 * Caller must hold rt6_exception_lock
1483 */
1484static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
1485{
1486 struct rt6_exception *rt6_ex, *oldest = NULL;
1487
1488 if (!bucket)
1489 return;
1490
1491 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1492 if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
1493 oldest = rt6_ex;
1494 }
1495 rt6_remove_exception(bucket, oldest);
1496}
1497
1498static u32 rt6_exception_hash(const struct in6_addr *dst,
1499 const struct in6_addr *src)
1500{
1501 static siphash_aligned_key_t rt6_exception_key;
1502 struct {
1503 struct in6_addr dst;
1504 struct in6_addr src;
1505 } __aligned(SIPHASH_ALIGNMENT) combined = {
1506 .dst = *dst,
1507 };
1508 u64 val;
1509
1510 net_get_random_once(&rt6_exception_key, sizeof(rt6_exception_key));
1511
1512#ifdef CONFIG_IPV6_SUBTREES
1513 if (src)
1514 combined.src = *src;
1515#endif
1516 val = siphash(&combined, sizeof(combined), &rt6_exception_key);
1517
1518 return hash_64(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
1519}
1520
1521/* Helper function to find the cached rt in the hash table
1522 * and update bucket pointer to point to the bucket for this
1523 * (daddr, saddr) pair
1524 * Caller must hold rt6_exception_lock
1525 */
1526static struct rt6_exception *
1527__rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
1528 const struct in6_addr *daddr,
1529 const struct in6_addr *saddr)
1530{
1531 struct rt6_exception *rt6_ex;
1532 u32 hval;
1533
1534 if (!(*bucket) || !daddr)
1535 return NULL;
1536
1537 hval = rt6_exception_hash(daddr, saddr);
1538 *bucket += hval;
1539
1540 hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
1541 struct rt6_info *rt6 = rt6_ex->rt6i;
1542 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1543
1544#ifdef CONFIG_IPV6_SUBTREES
1545 if (matched && saddr)
1546 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1547#endif
1548 if (matched)
1549 return rt6_ex;
1550 }
1551 return NULL;
1552}
1553
1554/* Helper function to find the cached rt in the hash table
1555 * and update bucket pointer to point to the bucket for this
1556 * (daddr, saddr) pair
1557 * Caller must hold rcu_read_lock()
1558 */
1559static struct rt6_exception *
1560__rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
1561 const struct in6_addr *daddr,
1562 const struct in6_addr *saddr)
1563{
1564 struct rt6_exception *rt6_ex;
1565 u32 hval;
1566
1567 WARN_ON_ONCE(!rcu_read_lock_held());
1568
1569 if (!(*bucket) || !daddr)
1570 return NULL;
1571
1572 hval = rt6_exception_hash(daddr, saddr);
1573 *bucket += hval;
1574
1575 hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
1576 struct rt6_info *rt6 = rt6_ex->rt6i;
1577 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1578
1579#ifdef CONFIG_IPV6_SUBTREES
1580 if (matched && saddr)
1581 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1582#endif
1583 if (matched)
1584 return rt6_ex;
1585 }
1586 return NULL;
1587}
1588
1589static unsigned int fib6_mtu(const struct fib6_result *res)
1590{
1591 const struct fib6_nh *nh = res->nh;
1592 unsigned int mtu;
1593
1594 if (res->f6i->fib6_pmtu) {
1595 mtu = res->f6i->fib6_pmtu;
1596 } else {
1597 struct net_device *dev = nh->fib_nh_dev;
1598 struct inet6_dev *idev;
1599
1600 rcu_read_lock();
1601 idev = __in6_dev_get(dev);
1602 mtu = READ_ONCE(idev->cnf.mtu6);
1603 rcu_read_unlock();
1604 }
1605
1606 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1607
1608 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
1609}
1610
1611#define FIB6_EXCEPTION_BUCKET_FLUSHED 0x1UL
1612
1613/* used when the flushed bit is not relevant, only access to the bucket
1614 * (ie., all bucket users except rt6_insert_exception);
1615 *
1616 * called under rcu lock; sometimes called with rt6_exception_lock held
1617 */
1618static
1619struct rt6_exception_bucket *fib6_nh_get_excptn_bucket(const struct fib6_nh *nh,
1620 spinlock_t *lock)
1621{
1622 struct rt6_exception_bucket *bucket;
1623
1624 if (lock)
1625 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1626 lockdep_is_held(lock));
1627 else
1628 bucket = rcu_dereference(nh->rt6i_exception_bucket);
1629
1630 /* remove bucket flushed bit if set */
1631 if (bucket) {
1632 unsigned long p = (unsigned long)bucket;
1633
1634 p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED;
1635 bucket = (struct rt6_exception_bucket *)p;
1636 }
1637
1638 return bucket;
1639}
1640
1641static bool fib6_nh_excptn_bucket_flushed(struct rt6_exception_bucket *bucket)
1642{
1643 unsigned long p = (unsigned long)bucket;
1644
1645 return !!(p & FIB6_EXCEPTION_BUCKET_FLUSHED);
1646}
1647
1648/* called with rt6_exception_lock held */
1649static void fib6_nh_excptn_bucket_set_flushed(struct fib6_nh *nh,
1650 spinlock_t *lock)
1651{
1652 struct rt6_exception_bucket *bucket;
1653 unsigned long p;
1654
1655 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1656 lockdep_is_held(lock));
1657
1658 p = (unsigned long)bucket;
1659 p |= FIB6_EXCEPTION_BUCKET_FLUSHED;
1660 bucket = (struct rt6_exception_bucket *)p;
1661 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1662}
1663
1664static int rt6_insert_exception(struct rt6_info *nrt,
1665 const struct fib6_result *res)
1666{
1667 struct net *net = dev_net(nrt->dst.dev);
1668 struct rt6_exception_bucket *bucket;
1669 struct fib6_info *f6i = res->f6i;
1670 struct in6_addr *src_key = NULL;
1671 struct rt6_exception *rt6_ex;
1672 struct fib6_nh *nh = res->nh;
1673 int max_depth;
1674 int err = 0;
1675
1676 spin_lock_bh(&rt6_exception_lock);
1677
1678 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1679 lockdep_is_held(&rt6_exception_lock));
1680 if (!bucket) {
1681 bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
1682 GFP_ATOMIC);
1683 if (!bucket) {
1684 err = -ENOMEM;
1685 goto out;
1686 }
1687 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1688 } else if (fib6_nh_excptn_bucket_flushed(bucket)) {
1689 err = -EINVAL;
1690 goto out;
1691 }
1692
1693#ifdef CONFIG_IPV6_SUBTREES
1694 /* fib6_src.plen != 0 indicates f6i is in subtree
1695 * and exception table is indexed by a hash of
1696 * both fib6_dst and fib6_src.
1697 * Otherwise, the exception table is indexed by
1698 * a hash of only fib6_dst.
1699 */
1700 if (f6i->fib6_src.plen)
1701 src_key = &nrt->rt6i_src.addr;
1702#endif
1703 /* rt6_mtu_change() might lower mtu on f6i.
1704 * Only insert this exception route if its mtu
1705 * is less than f6i's mtu value.
1706 */
1707 if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(res)) {
1708 err = -EINVAL;
1709 goto out;
1710 }
1711
1712 rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
1713 src_key);
1714 if (rt6_ex)
1715 rt6_remove_exception(bucket, rt6_ex);
1716
1717 rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
1718 if (!rt6_ex) {
1719 err = -ENOMEM;
1720 goto out;
1721 }
1722 rt6_ex->rt6i = nrt;
1723 rt6_ex->stamp = jiffies;
1724 hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
1725 bucket->depth++;
1726 net->ipv6.rt6_stats->fib_rt_cache++;
1727
1728 /* Randomize max depth to avoid some side channels attacks. */
1729 max_depth = FIB6_MAX_DEPTH + get_random_u32_below(FIB6_MAX_DEPTH);
1730 while (bucket->depth > max_depth)
1731 rt6_exception_remove_oldest(bucket);
1732
1733out:
1734 spin_unlock_bh(&rt6_exception_lock);
1735
1736 /* Update fn->fn_sernum to invalidate all cached dst */
1737 if (!err) {
1738 spin_lock_bh(&f6i->fib6_table->tb6_lock);
1739 fib6_update_sernum(net, f6i);
1740 spin_unlock_bh(&f6i->fib6_table->tb6_lock);
1741 fib6_force_start_gc(net);
1742 }
1743
1744 return err;
1745}
1746
1747static void fib6_nh_flush_exceptions(struct fib6_nh *nh, struct fib6_info *from)
1748{
1749 struct rt6_exception_bucket *bucket;
1750 struct rt6_exception *rt6_ex;
1751 struct hlist_node *tmp;
1752 int i;
1753
1754 spin_lock_bh(&rt6_exception_lock);
1755
1756 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1757 if (!bucket)
1758 goto out;
1759
1760 /* Prevent rt6_insert_exception() to recreate the bucket list */
1761 if (!from)
1762 fib6_nh_excptn_bucket_set_flushed(nh, &rt6_exception_lock);
1763
1764 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1765 hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist) {
1766 if (!from ||
1767 rcu_access_pointer(rt6_ex->rt6i->from) == from)
1768 rt6_remove_exception(bucket, rt6_ex);
1769 }
1770 WARN_ON_ONCE(!from && bucket->depth);
1771 bucket++;
1772 }
1773out:
1774 spin_unlock_bh(&rt6_exception_lock);
1775}
1776
1777static int rt6_nh_flush_exceptions(struct fib6_nh *nh, void *arg)
1778{
1779 struct fib6_info *f6i = arg;
1780
1781 fib6_nh_flush_exceptions(nh, f6i);
1782
1783 return 0;
1784}
1785
1786void rt6_flush_exceptions(struct fib6_info *f6i)
1787{
1788 if (f6i->nh)
1789 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions,
1790 f6i);
1791 else
1792 fib6_nh_flush_exceptions(f6i->fib6_nh, f6i);
1793}
1794
1795/* Find cached rt in the hash table inside passed in rt
1796 * Caller has to hold rcu_read_lock()
1797 */
1798static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
1799 const struct in6_addr *daddr,
1800 const struct in6_addr *saddr)
1801{
1802 const struct in6_addr *src_key = NULL;
1803 struct rt6_exception_bucket *bucket;
1804 struct rt6_exception *rt6_ex;
1805 struct rt6_info *ret = NULL;
1806
1807#ifdef CONFIG_IPV6_SUBTREES
1808 /* fib6i_src.plen != 0 indicates f6i is in subtree
1809 * and exception table is indexed by a hash of
1810 * both fib6_dst and fib6_src.
1811 * However, the src addr used to create the hash
1812 * might not be exactly the passed in saddr which
1813 * is a /128 addr from the flow.
1814 * So we need to use f6i->fib6_src to redo lookup
1815 * if the passed in saddr does not find anything.
1816 * (See the logic in ip6_rt_cache_alloc() on how
1817 * rt->rt6i_src is updated.)
1818 */
1819 if (res->f6i->fib6_src.plen)
1820 src_key = saddr;
1821find_ex:
1822#endif
1823 bucket = fib6_nh_get_excptn_bucket(res->nh, NULL);
1824 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
1825
1826 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
1827 ret = rt6_ex->rt6i;
1828
1829#ifdef CONFIG_IPV6_SUBTREES
1830 /* Use fib6_src as src_key and redo lookup */
1831 if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) {
1832 src_key = &res->f6i->fib6_src.addr;
1833 goto find_ex;
1834 }
1835#endif
1836
1837 return ret;
1838}
1839
1840/* Remove the passed in cached rt from the hash table that contains it */
1841static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen,
1842 const struct rt6_info *rt)
1843{
1844 const struct in6_addr *src_key = NULL;
1845 struct rt6_exception_bucket *bucket;
1846 struct rt6_exception *rt6_ex;
1847 int err;
1848
1849 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
1850 return -ENOENT;
1851
1852 spin_lock_bh(&rt6_exception_lock);
1853 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1854
1855#ifdef CONFIG_IPV6_SUBTREES
1856 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1857 * and exception table is indexed by a hash of
1858 * both rt6i_dst and rt6i_src.
1859 * Otherwise, the exception table is indexed by
1860 * a hash of only rt6i_dst.
1861 */
1862 if (plen)
1863 src_key = &rt->rt6i_src.addr;
1864#endif
1865 rt6_ex = __rt6_find_exception_spinlock(&bucket,
1866 &rt->rt6i_dst.addr,
1867 src_key);
1868 if (rt6_ex) {
1869 rt6_remove_exception(bucket, rt6_ex);
1870 err = 0;
1871 } else {
1872 err = -ENOENT;
1873 }
1874
1875 spin_unlock_bh(&rt6_exception_lock);
1876 return err;
1877}
1878
1879struct fib6_nh_excptn_arg {
1880 struct rt6_info *rt;
1881 int plen;
1882};
1883
1884static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg)
1885{
1886 struct fib6_nh_excptn_arg *arg = _arg;
1887 int err;
1888
1889 err = fib6_nh_remove_exception(nh, arg->plen, arg->rt);
1890 if (err == 0)
1891 return 1;
1892
1893 return 0;
1894}
1895
1896static int rt6_remove_exception_rt(struct rt6_info *rt)
1897{
1898 struct fib6_info *from;
1899
1900 from = rcu_dereference(rt->from);
1901 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1902 return -EINVAL;
1903
1904 if (from->nh) {
1905 struct fib6_nh_excptn_arg arg = {
1906 .rt = rt,
1907 .plen = from->fib6_src.plen
1908 };
1909 int rc;
1910
1911 /* rc = 1 means an entry was found */
1912 rc = nexthop_for_each_fib6_nh(from->nh,
1913 rt6_nh_remove_exception_rt,
1914 &arg);
1915 return rc ? 0 : -ENOENT;
1916 }
1917
1918 return fib6_nh_remove_exception(from->fib6_nh,
1919 from->fib6_src.plen, rt);
1920}
1921
1922/* Find rt6_ex which contains the passed in rt cache and
1923 * refresh its stamp
1924 */
1925static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen,
1926 const struct rt6_info *rt)
1927{
1928 const struct in6_addr *src_key = NULL;
1929 struct rt6_exception_bucket *bucket;
1930 struct rt6_exception *rt6_ex;
1931
1932 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
1933#ifdef CONFIG_IPV6_SUBTREES
1934 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1935 * and exception table is indexed by a hash of
1936 * both rt6i_dst and rt6i_src.
1937 * Otherwise, the exception table is indexed by
1938 * a hash of only rt6i_dst.
1939 */
1940 if (plen)
1941 src_key = &rt->rt6i_src.addr;
1942#endif
1943 rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key);
1944 if (rt6_ex)
1945 rt6_ex->stamp = jiffies;
1946}
1947
1948struct fib6_nh_match_arg {
1949 const struct net_device *dev;
1950 const struct in6_addr *gw;
1951 struct fib6_nh *match;
1952};
1953
1954/* determine if fib6_nh has given device and gateway */
1955static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg)
1956{
1957 struct fib6_nh_match_arg *arg = _arg;
1958
1959 if (arg->dev != nh->fib_nh_dev ||
1960 (arg->gw && !nh->fib_nh_gw_family) ||
1961 (!arg->gw && nh->fib_nh_gw_family) ||
1962 (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6)))
1963 return 0;
1964
1965 arg->match = nh;
1966
1967 /* found a match, break the loop */
1968 return 1;
1969}
1970
1971static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
1972{
1973 struct fib6_info *from;
1974 struct fib6_nh *fib6_nh;
1975
1976 rcu_read_lock();
1977
1978 from = rcu_dereference(rt->from);
1979 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1980 goto unlock;
1981
1982 if (from->nh) {
1983 struct fib6_nh_match_arg arg = {
1984 .dev = rt->dst.dev,
1985 .gw = &rt->rt6i_gateway,
1986 };
1987
1988 nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg);
1989
1990 if (!arg.match)
1991 goto unlock;
1992 fib6_nh = arg.match;
1993 } else {
1994 fib6_nh = from->fib6_nh;
1995 }
1996 fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt);
1997unlock:
1998 rcu_read_unlock();
1999}
2000
2001static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
2002 struct rt6_info *rt, int mtu)
2003{
2004 /* If the new MTU is lower than the route PMTU, this new MTU will be the
2005 * lowest MTU in the path: always allow updating the route PMTU to
2006 * reflect PMTU decreases.
2007 *
2008 * If the new MTU is higher, and the route PMTU is equal to the local
2009 * MTU, this means the old MTU is the lowest in the path, so allow
2010 * updating it: if other nodes now have lower MTUs, PMTU discovery will
2011 * handle this.
2012 */
2013
2014 if (dst_mtu(&rt->dst) >= mtu)
2015 return true;
2016
2017 if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
2018 return true;
2019
2020 return false;
2021}
2022
2023static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
2024 const struct fib6_nh *nh, int mtu)
2025{
2026 struct rt6_exception_bucket *bucket;
2027 struct rt6_exception *rt6_ex;
2028 int i;
2029
2030 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2031 if (!bucket)
2032 return;
2033
2034 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2035 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
2036 struct rt6_info *entry = rt6_ex->rt6i;
2037
2038 /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
2039 * route), the metrics of its rt->from have already
2040 * been updated.
2041 */
2042 if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
2043 rt6_mtu_change_route_allowed(idev, entry, mtu))
2044 dst_metric_set(&entry->dst, RTAX_MTU, mtu);
2045 }
2046 bucket++;
2047 }
2048}
2049
2050#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2051
2052static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh,
2053 const struct in6_addr *gateway)
2054{
2055 struct rt6_exception_bucket *bucket;
2056 struct rt6_exception *rt6_ex;
2057 struct hlist_node *tmp;
2058 int i;
2059
2060 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2061 return;
2062
2063 spin_lock_bh(&rt6_exception_lock);
2064 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2065 if (bucket) {
2066 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2067 hlist_for_each_entry_safe(rt6_ex, tmp,
2068 &bucket->chain, hlist) {
2069 struct rt6_info *entry = rt6_ex->rt6i;
2070
2071 if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
2072 RTF_CACHE_GATEWAY &&
2073 ipv6_addr_equal(gateway,
2074 &entry->rt6i_gateway)) {
2075 rt6_remove_exception(bucket, rt6_ex);
2076 }
2077 }
2078 bucket++;
2079 }
2080 }
2081
2082 spin_unlock_bh(&rt6_exception_lock);
2083}
2084
2085static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
2086 struct rt6_exception *rt6_ex,
2087 struct fib6_gc_args *gc_args,
2088 unsigned long now)
2089{
2090 struct rt6_info *rt = rt6_ex->rt6i;
2091
2092 /* we are pruning and obsoleting aged-out and non gateway exceptions
2093 * even if others have still references to them, so that on next
2094 * dst_check() such references can be dropped.
2095 * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
2096 * expired, independently from their aging, as per RFC 8201 section 4
2097 */
2098 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
2099 if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
2100 pr_debug("aging clone %p\n", rt);
2101 rt6_remove_exception(bucket, rt6_ex);
2102 return;
2103 }
2104 } else if (time_after(jiffies, rt->dst.expires)) {
2105 pr_debug("purging expired route %p\n", rt);
2106 rt6_remove_exception(bucket, rt6_ex);
2107 return;
2108 }
2109
2110 if (rt->rt6i_flags & RTF_GATEWAY) {
2111 struct neighbour *neigh;
2112
2113 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
2114
2115 if (!(neigh && (neigh->flags & NTF_ROUTER))) {
2116 pr_debug("purging route %p via non-router but gateway\n",
2117 rt);
2118 rt6_remove_exception(bucket, rt6_ex);
2119 return;
2120 }
2121 }
2122
2123 gc_args->more++;
2124}
2125
2126static void fib6_nh_age_exceptions(const struct fib6_nh *nh,
2127 struct fib6_gc_args *gc_args,
2128 unsigned long now)
2129{
2130 struct rt6_exception_bucket *bucket;
2131 struct rt6_exception *rt6_ex;
2132 struct hlist_node *tmp;
2133 int i;
2134
2135 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2136 return;
2137
2138 rcu_read_lock_bh();
2139 spin_lock(&rt6_exception_lock);
2140 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2141 if (bucket) {
2142 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2143 hlist_for_each_entry_safe(rt6_ex, tmp,
2144 &bucket->chain, hlist) {
2145 rt6_age_examine_exception(bucket, rt6_ex,
2146 gc_args, now);
2147 }
2148 bucket++;
2149 }
2150 }
2151 spin_unlock(&rt6_exception_lock);
2152 rcu_read_unlock_bh();
2153}
2154
2155struct fib6_nh_age_excptn_arg {
2156 struct fib6_gc_args *gc_args;
2157 unsigned long now;
2158};
2159
2160static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg)
2161{
2162 struct fib6_nh_age_excptn_arg *arg = _arg;
2163
2164 fib6_nh_age_exceptions(nh, arg->gc_args, arg->now);
2165 return 0;
2166}
2167
2168void rt6_age_exceptions(struct fib6_info *f6i,
2169 struct fib6_gc_args *gc_args,
2170 unsigned long now)
2171{
2172 if (f6i->nh) {
2173 struct fib6_nh_age_excptn_arg arg = {
2174 .gc_args = gc_args,
2175 .now = now
2176 };
2177
2178 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions,
2179 &arg);
2180 } else {
2181 fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now);
2182 }
2183}
2184
2185/* must be called with rcu lock held */
2186int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif,
2187 struct flowi6 *fl6, struct fib6_result *res, int strict)
2188{
2189 struct fib6_node *fn, *saved_fn;
2190
2191 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2192 saved_fn = fn;
2193
2194redo_rt6_select:
2195 rt6_select(net, fn, oif, res, strict);
2196 if (res->f6i == net->ipv6.fib6_null_entry) {
2197 fn = fib6_backtrack(fn, &fl6->saddr);
2198 if (fn)
2199 goto redo_rt6_select;
2200 else if (strict & RT6_LOOKUP_F_REACHABLE) {
2201 /* also consider unreachable route */
2202 strict &= ~RT6_LOOKUP_F_REACHABLE;
2203 fn = saved_fn;
2204 goto redo_rt6_select;
2205 }
2206 }
2207
2208 trace_fib6_table_lookup(net, res, table, fl6);
2209
2210 return 0;
2211}
2212
2213struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
2214 int oif, struct flowi6 *fl6,
2215 const struct sk_buff *skb, int flags)
2216{
2217 struct fib6_result res = {};
2218 struct rt6_info *rt = NULL;
2219 int strict = 0;
2220
2221 WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) &&
2222 !rcu_read_lock_held());
2223
2224 strict |= flags & RT6_LOOKUP_F_IFACE;
2225 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
2226 if (READ_ONCE(net->ipv6.devconf_all->forwarding) == 0)
2227 strict |= RT6_LOOKUP_F_REACHABLE;
2228
2229 rcu_read_lock();
2230
2231 fib6_table_lookup(net, table, oif, fl6, &res, strict);
2232 if (res.f6i == net->ipv6.fib6_null_entry)
2233 goto out;
2234
2235 fib6_select_path(net, &res, fl6, oif, false, skb, strict);
2236
2237 /*Search through exception table */
2238 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
2239 if (rt) {
2240 goto out;
2241 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
2242 !res.nh->fib_nh_gw_family)) {
2243 /* Create a RTF_CACHE clone which will not be
2244 * owned by the fib6 tree. It is for the special case where
2245 * the daddr in the skb during the neighbor look-up is different
2246 * from the fl6->daddr used to look-up route here.
2247 */
2248 rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL);
2249
2250 if (rt) {
2251 /* 1 refcnt is taken during ip6_rt_cache_alloc().
2252 * As rt6_uncached_list_add() does not consume refcnt,
2253 * this refcnt is always returned to the caller even
2254 * if caller sets RT6_LOOKUP_F_DST_NOREF flag.
2255 */
2256 rt6_uncached_list_add(rt);
2257 rcu_read_unlock();
2258
2259 return rt;
2260 }
2261 } else {
2262 /* Get a percpu copy */
2263 local_bh_disable();
2264 rt = rt6_get_pcpu_route(&res);
2265
2266 if (!rt)
2267 rt = rt6_make_pcpu_route(net, &res);
2268
2269 local_bh_enable();
2270 }
2271out:
2272 if (!rt)
2273 rt = net->ipv6.ip6_null_entry;
2274 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
2275 ip6_hold_safe(net, &rt);
2276 rcu_read_unlock();
2277
2278 return rt;
2279}
2280EXPORT_SYMBOL_GPL(ip6_pol_route);
2281
2282INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_input(struct net *net,
2283 struct fib6_table *table,
2284 struct flowi6 *fl6,
2285 const struct sk_buff *skb,
2286 int flags)
2287{
2288 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags);
2289}
2290
2291struct dst_entry *ip6_route_input_lookup(struct net *net,
2292 struct net_device *dev,
2293 struct flowi6 *fl6,
2294 const struct sk_buff *skb,
2295 int flags)
2296{
2297 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
2298 flags |= RT6_LOOKUP_F_IFACE;
2299
2300 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input);
2301}
2302EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
2303
2304static void ip6_multipath_l3_keys(const struct sk_buff *skb,
2305 struct flow_keys *keys,
2306 struct flow_keys *flkeys)
2307{
2308 const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
2309 const struct ipv6hdr *key_iph = outer_iph;
2310 struct flow_keys *_flkeys = flkeys;
2311 const struct ipv6hdr *inner_iph;
2312 const struct icmp6hdr *icmph;
2313 struct ipv6hdr _inner_iph;
2314 struct icmp6hdr _icmph;
2315
2316 if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6))
2317 goto out;
2318
2319 icmph = skb_header_pointer(skb, skb_transport_offset(skb),
2320 sizeof(_icmph), &_icmph);
2321 if (!icmph)
2322 goto out;
2323
2324 if (!icmpv6_is_err(icmph->icmp6_type))
2325 goto out;
2326
2327 inner_iph = skb_header_pointer(skb,
2328 skb_transport_offset(skb) + sizeof(*icmph),
2329 sizeof(_inner_iph), &_inner_iph);
2330 if (!inner_iph)
2331 goto out;
2332
2333 key_iph = inner_iph;
2334 _flkeys = NULL;
2335out:
2336 if (_flkeys) {
2337 keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src;
2338 keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst;
2339 keys->tags.flow_label = _flkeys->tags.flow_label;
2340 keys->basic.ip_proto = _flkeys->basic.ip_proto;
2341 } else {
2342 keys->addrs.v6addrs.src = key_iph->saddr;
2343 keys->addrs.v6addrs.dst = key_iph->daddr;
2344 keys->tags.flow_label = ip6_flowlabel(key_iph);
2345 keys->basic.ip_proto = key_iph->nexthdr;
2346 }
2347}
2348
2349static u32 rt6_multipath_custom_hash_outer(const struct net *net,
2350 const struct sk_buff *skb,
2351 bool *p_has_inner)
2352{
2353 u32 hash_fields = ip6_multipath_hash_fields(net);
2354 struct flow_keys keys, hash_keys;
2355
2356 if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK))
2357 return 0;
2358
2359 memset(&hash_keys, 0, sizeof(hash_keys));
2360 skb_flow_dissect_flow_keys(skb, &keys, FLOW_DISSECTOR_F_STOP_AT_ENCAP);
2361
2362 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2363 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_IP)
2364 hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src;
2365 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_IP)
2366 hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst;
2367 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
2368 hash_keys.basic.ip_proto = keys.basic.ip_proto;
2369 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_FLOWLABEL)
2370 hash_keys.tags.flow_label = keys.tags.flow_label;
2371 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_PORT)
2372 hash_keys.ports.src = keys.ports.src;
2373 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT)
2374 hash_keys.ports.dst = keys.ports.dst;
2375
2376 *p_has_inner = !!(keys.control.flags & FLOW_DIS_ENCAPSULATION);
2377 return fib_multipath_hash_from_keys(net, &hash_keys);
2378}
2379
2380static u32 rt6_multipath_custom_hash_inner(const struct net *net,
2381 const struct sk_buff *skb,
2382 bool has_inner)
2383{
2384 u32 hash_fields = ip6_multipath_hash_fields(net);
2385 struct flow_keys keys, hash_keys;
2386
2387 /* We assume the packet carries an encapsulation, but if none was
2388 * encountered during dissection of the outer flow, then there is no
2389 * point in calling the flow dissector again.
2390 */
2391 if (!has_inner)
2392 return 0;
2393
2394 if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_MASK))
2395 return 0;
2396
2397 memset(&hash_keys, 0, sizeof(hash_keys));
2398 skb_flow_dissect_flow_keys(skb, &keys, 0);
2399
2400 if (!(keys.control.flags & FLOW_DIS_ENCAPSULATION))
2401 return 0;
2402
2403 if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
2404 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
2405 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP)
2406 hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src;
2407 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP)
2408 hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst;
2409 } else if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
2410 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2411 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP)
2412 hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src;
2413 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP)
2414 hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst;
2415 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL)
2416 hash_keys.tags.flow_label = keys.tags.flow_label;
2417 }
2418
2419 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO)
2420 hash_keys.basic.ip_proto = keys.basic.ip_proto;
2421 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT)
2422 hash_keys.ports.src = keys.ports.src;
2423 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
2424 hash_keys.ports.dst = keys.ports.dst;
2425
2426 return fib_multipath_hash_from_keys(net, &hash_keys);
2427}
2428
2429static u32 rt6_multipath_custom_hash_skb(const struct net *net,
2430 const struct sk_buff *skb)
2431{
2432 u32 mhash, mhash_inner;
2433 bool has_inner = true;
2434
2435 mhash = rt6_multipath_custom_hash_outer(net, skb, &has_inner);
2436 mhash_inner = rt6_multipath_custom_hash_inner(net, skb, has_inner);
2437
2438 return jhash_2words(mhash, mhash_inner, 0);
2439}
2440
2441static u32 rt6_multipath_custom_hash_fl6(const struct net *net,
2442 const struct flowi6 *fl6)
2443{
2444 u32 hash_fields = ip6_multipath_hash_fields(net);
2445 struct flow_keys hash_keys;
2446
2447 if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK))
2448 return 0;
2449
2450 memset(&hash_keys, 0, sizeof(hash_keys));
2451 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2452 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_IP)
2453 hash_keys.addrs.v6addrs.src = fl6->saddr;
2454 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_IP)
2455 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2456 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
2457 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2458 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_FLOWLABEL)
2459 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2460 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_PORT)
2461 hash_keys.ports.src = fl6->fl6_sport;
2462 if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT)
2463 hash_keys.ports.dst = fl6->fl6_dport;
2464
2465 return fib_multipath_hash_from_keys(net, &hash_keys);
2466}
2467
2468/* if skb is set it will be used and fl6 can be NULL */
2469u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
2470 const struct sk_buff *skb, struct flow_keys *flkeys)
2471{
2472 struct flow_keys hash_keys;
2473 u32 mhash = 0;
2474
2475 switch (ip6_multipath_hash_policy(net)) {
2476 case 0:
2477 memset(&hash_keys, 0, sizeof(hash_keys));
2478 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2479 if (skb) {
2480 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2481 } else {
2482 hash_keys.addrs.v6addrs.src = fl6->saddr;
2483 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2484 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2485 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2486 }
2487 mhash = fib_multipath_hash_from_keys(net, &hash_keys);
2488 break;
2489 case 1:
2490 if (skb) {
2491 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
2492 struct flow_keys keys;
2493
2494 /* short-circuit if we already have L4 hash present */
2495 if (skb->l4_hash)
2496 return skb_get_hash_raw(skb) >> 1;
2497
2498 memset(&hash_keys, 0, sizeof(hash_keys));
2499
2500 if (!flkeys) {
2501 skb_flow_dissect_flow_keys(skb, &keys, flag);
2502 flkeys = &keys;
2503 }
2504 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2505 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2506 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2507 hash_keys.ports.src = flkeys->ports.src;
2508 hash_keys.ports.dst = flkeys->ports.dst;
2509 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2510 } else {
2511 memset(&hash_keys, 0, sizeof(hash_keys));
2512 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2513 hash_keys.addrs.v6addrs.src = fl6->saddr;
2514 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2515 hash_keys.ports.src = fl6->fl6_sport;
2516 hash_keys.ports.dst = fl6->fl6_dport;
2517 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2518 }
2519 mhash = fib_multipath_hash_from_keys(net, &hash_keys);
2520 break;
2521 case 2:
2522 memset(&hash_keys, 0, sizeof(hash_keys));
2523 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2524 if (skb) {
2525 struct flow_keys keys;
2526
2527 if (!flkeys) {
2528 skb_flow_dissect_flow_keys(skb, &keys, 0);
2529 flkeys = &keys;
2530 }
2531
2532 /* Inner can be v4 or v6 */
2533 if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
2534 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
2535 hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src;
2536 hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst;
2537 } else if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
2538 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2539 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2540 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2541 hash_keys.tags.flow_label = flkeys->tags.flow_label;
2542 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2543 } else {
2544 /* Same as case 0 */
2545 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2546 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2547 }
2548 } else {
2549 /* Same as case 0 */
2550 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2551 hash_keys.addrs.v6addrs.src = fl6->saddr;
2552 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2553 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2554 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2555 }
2556 mhash = fib_multipath_hash_from_keys(net, &hash_keys);
2557 break;
2558 case 3:
2559 if (skb)
2560 mhash = rt6_multipath_custom_hash_skb(net, skb);
2561 else
2562 mhash = rt6_multipath_custom_hash_fl6(net, fl6);
2563 break;
2564 }
2565
2566 return mhash >> 1;
2567}
2568
2569/* Called with rcu held */
2570void ip6_route_input(struct sk_buff *skb)
2571{
2572 const struct ipv6hdr *iph = ipv6_hdr(skb);
2573 struct net *net = dev_net(skb->dev);
2574 int flags = RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_DST_NOREF;
2575 struct ip_tunnel_info *tun_info;
2576 struct flowi6 fl6 = {
2577 .flowi6_iif = skb->dev->ifindex,
2578 .daddr = iph->daddr,
2579 .saddr = iph->saddr,
2580 .flowlabel = ip6_flowinfo(iph),
2581 .flowi6_mark = skb->mark,
2582 .flowi6_proto = iph->nexthdr,
2583 };
2584 struct flow_keys *flkeys = NULL, _flkeys;
2585
2586 tun_info = skb_tunnel_info(skb);
2587 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
2588 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
2589
2590 if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys))
2591 flkeys = &_flkeys;
2592
2593 if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6))
2594 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys);
2595 skb_dst_drop(skb);
2596 skb_dst_set_noref(skb, ip6_route_input_lookup(net, skb->dev,
2597 &fl6, skb, flags));
2598}
2599
2600INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_output(struct net *net,
2601 struct fib6_table *table,
2602 struct flowi6 *fl6,
2603 const struct sk_buff *skb,
2604 int flags)
2605{
2606 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags);
2607}
2608
2609static struct dst_entry *ip6_route_output_flags_noref(struct net *net,
2610 const struct sock *sk,
2611 struct flowi6 *fl6,
2612 int flags)
2613{
2614 bool any_src;
2615
2616 if (ipv6_addr_type(&fl6->daddr) &
2617 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
2618 struct dst_entry *dst;
2619
2620 /* This function does not take refcnt on the dst */
2621 dst = l3mdev_link_scope_lookup(net, fl6);
2622 if (dst)
2623 return dst;
2624 }
2625
2626 fl6->flowi6_iif = LOOPBACK_IFINDEX;
2627
2628 flags |= RT6_LOOKUP_F_DST_NOREF;
2629 any_src = ipv6_addr_any(&fl6->saddr);
2630 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
2631 (fl6->flowi6_oif && any_src))
2632 flags |= RT6_LOOKUP_F_IFACE;
2633
2634 if (!any_src)
2635 flags |= RT6_LOOKUP_F_HAS_SADDR;
2636 else if (sk)
2637 flags |= rt6_srcprefs2flags(READ_ONCE(inet6_sk(sk)->srcprefs));
2638
2639 return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
2640}
2641
2642struct dst_entry *ip6_route_output_flags(struct net *net,
2643 const struct sock *sk,
2644 struct flowi6 *fl6,
2645 int flags)
2646{
2647 struct dst_entry *dst;
2648 struct rt6_info *rt6;
2649
2650 rcu_read_lock();
2651 dst = ip6_route_output_flags_noref(net, sk, fl6, flags);
2652 rt6 = dst_rt6_info(dst);
2653 /* For dst cached in uncached_list, refcnt is already taken. */
2654 if (list_empty(&rt6->dst.rt_uncached) && !dst_hold_safe(dst)) {
2655 dst = &net->ipv6.ip6_null_entry->dst;
2656 dst_hold(dst);
2657 }
2658 rcu_read_unlock();
2659
2660 return dst;
2661}
2662EXPORT_SYMBOL_GPL(ip6_route_output_flags);
2663
2664struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2665{
2666 struct rt6_info *rt, *ort = dst_rt6_info(dst_orig);
2667 struct net_device *loopback_dev = net->loopback_dev;
2668 struct dst_entry *new = NULL;
2669
2670 rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev,
2671 DST_OBSOLETE_DEAD, 0);
2672 if (rt) {
2673 rt6_info_init(rt);
2674 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
2675
2676 new = &rt->dst;
2677 new->__use = 1;
2678 new->input = dst_discard;
2679 new->output = dst_discard_out;
2680
2681 dst_copy_metrics(new, &ort->dst);
2682
2683 rt->rt6i_idev = in6_dev_get(loopback_dev);
2684 rt->rt6i_gateway = ort->rt6i_gateway;
2685 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
2686
2687 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
2688#ifdef CONFIG_IPV6_SUBTREES
2689 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
2690#endif
2691 }
2692
2693 dst_release(dst_orig);
2694 return new ? new : ERR_PTR(-ENOMEM);
2695}
2696
2697/*
2698 * Destination cache support functions
2699 */
2700
2701static bool fib6_check(struct fib6_info *f6i, u32 cookie)
2702{
2703 u32 rt_cookie = 0;
2704
2705 if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
2706 return false;
2707
2708 if (fib6_check_expired(f6i))
2709 return false;
2710
2711 return true;
2712}
2713
2714static struct dst_entry *rt6_check(struct rt6_info *rt,
2715 struct fib6_info *from,
2716 u32 cookie)
2717{
2718 u32 rt_cookie = 0;
2719
2720 if (!from || !fib6_get_cookie_safe(from, &rt_cookie) ||
2721 rt_cookie != cookie)
2722 return NULL;
2723
2724 if (rt6_check_expired(rt))
2725 return NULL;
2726
2727 return &rt->dst;
2728}
2729
2730static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
2731 struct fib6_info *from,
2732 u32 cookie)
2733{
2734 if (!__rt6_check_expired(rt) &&
2735 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
2736 fib6_check(from, cookie))
2737 return &rt->dst;
2738 else
2739 return NULL;
2740}
2741
2742INDIRECT_CALLABLE_SCOPE struct dst_entry *ip6_dst_check(struct dst_entry *dst,
2743 u32 cookie)
2744{
2745 struct dst_entry *dst_ret;
2746 struct fib6_info *from;
2747 struct rt6_info *rt;
2748
2749 rt = dst_rt6_info(dst);
2750
2751 if (rt->sernum)
2752 return rt6_is_valid(rt) ? dst : NULL;
2753
2754 rcu_read_lock();
2755
2756 /* All IPV6 dsts are created with ->obsolete set to the value
2757 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
2758 * into this function always.
2759 */
2760
2761 from = rcu_dereference(rt->from);
2762
2763 if (from && (rt->rt6i_flags & RTF_PCPU ||
2764 unlikely(!list_empty(&rt->dst.rt_uncached))))
2765 dst_ret = rt6_dst_from_check(rt, from, cookie);
2766 else
2767 dst_ret = rt6_check(rt, from, cookie);
2768
2769 rcu_read_unlock();
2770
2771 return dst_ret;
2772}
2773EXPORT_INDIRECT_CALLABLE(ip6_dst_check);
2774
2775static void ip6_negative_advice(struct sock *sk,
2776 struct dst_entry *dst)
2777{
2778 struct rt6_info *rt = dst_rt6_info(dst);
2779
2780 if (rt->rt6i_flags & RTF_CACHE) {
2781 rcu_read_lock();
2782 if (rt6_check_expired(rt)) {
2783 /* rt/dst can not be destroyed yet,
2784 * because of rcu_read_lock()
2785 */
2786 sk_dst_reset(sk);
2787 rt6_remove_exception_rt(rt);
2788 }
2789 rcu_read_unlock();
2790 return;
2791 }
2792 sk_dst_reset(sk);
2793}
2794
2795static void ip6_link_failure(struct sk_buff *skb)
2796{
2797 struct rt6_info *rt;
2798
2799 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
2800
2801 rt = dst_rt6_info(skb_dst(skb));
2802 if (rt) {
2803 rcu_read_lock();
2804 if (rt->rt6i_flags & RTF_CACHE) {
2805 rt6_remove_exception_rt(rt);
2806 } else {
2807 struct fib6_info *from;
2808 struct fib6_node *fn;
2809
2810 from = rcu_dereference(rt->from);
2811 if (from) {
2812 fn = rcu_dereference(from->fib6_node);
2813 if (fn && (rt->rt6i_flags & RTF_DEFAULT))
2814 WRITE_ONCE(fn->fn_sernum, -1);
2815 }
2816 }
2817 rcu_read_unlock();
2818 }
2819}
2820
2821static void rt6_update_expires(struct rt6_info *rt0, int timeout)
2822{
2823 if (!(rt0->rt6i_flags & RTF_EXPIRES)) {
2824 struct fib6_info *from;
2825
2826 rcu_read_lock();
2827 from = rcu_dereference(rt0->from);
2828 if (from)
2829 rt0->dst.expires = from->expires;
2830 rcu_read_unlock();
2831 }
2832
2833 dst_set_expires(&rt0->dst, timeout);
2834 rt0->rt6i_flags |= RTF_EXPIRES;
2835}
2836
2837static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
2838{
2839 struct net *net = dev_net(rt->dst.dev);
2840
2841 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
2842 rt->rt6i_flags |= RTF_MODIFIED;
2843 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
2844}
2845
2846static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
2847{
2848 return !(rt->rt6i_flags & RTF_CACHE) &&
2849 (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from));
2850}
2851
2852static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
2853 const struct ipv6hdr *iph, u32 mtu,
2854 bool confirm_neigh)
2855{
2856 const struct in6_addr *daddr, *saddr;
2857 struct rt6_info *rt6 = dst_rt6_info(dst);
2858
2859 /* Note: do *NOT* check dst_metric_locked(dst, RTAX_MTU)
2860 * IPv6 pmtu discovery isn't optional, so 'mtu lock' cannot disable it.
2861 * [see also comment in rt6_mtu_change_route()]
2862 */
2863
2864 if (iph) {
2865 daddr = &iph->daddr;
2866 saddr = &iph->saddr;
2867 } else if (sk) {
2868 daddr = &sk->sk_v6_daddr;
2869 saddr = &inet6_sk(sk)->saddr;
2870 } else {
2871 daddr = NULL;
2872 saddr = NULL;
2873 }
2874
2875 if (confirm_neigh)
2876 dst_confirm_neigh(dst, daddr);
2877
2878 if (mtu < IPV6_MIN_MTU)
2879 return;
2880 if (mtu >= dst_mtu(dst))
2881 return;
2882
2883 if (!rt6_cache_allowed_for_pmtu(rt6)) {
2884 rt6_do_update_pmtu(rt6, mtu);
2885 /* update rt6_ex->stamp for cache */
2886 if (rt6->rt6i_flags & RTF_CACHE)
2887 rt6_update_exception_stamp_rt(rt6);
2888 } else if (daddr) {
2889 struct fib6_result res = {};
2890 struct rt6_info *nrt6;
2891
2892 rcu_read_lock();
2893 res.f6i = rcu_dereference(rt6->from);
2894 if (!res.f6i)
2895 goto out_unlock;
2896
2897 res.fib6_flags = res.f6i->fib6_flags;
2898 res.fib6_type = res.f6i->fib6_type;
2899
2900 if (res.f6i->nh) {
2901 struct fib6_nh_match_arg arg = {
2902 .dev = dst->dev,
2903 .gw = &rt6->rt6i_gateway,
2904 };
2905
2906 nexthop_for_each_fib6_nh(res.f6i->nh,
2907 fib6_nh_find_match, &arg);
2908
2909 /* fib6_info uses a nexthop that does not have fib6_nh
2910 * using the dst->dev + gw. Should be impossible.
2911 */
2912 if (!arg.match)
2913 goto out_unlock;
2914
2915 res.nh = arg.match;
2916 } else {
2917 res.nh = res.f6i->fib6_nh;
2918 }
2919
2920 nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr);
2921 if (nrt6) {
2922 rt6_do_update_pmtu(nrt6, mtu);
2923 if (rt6_insert_exception(nrt6, &res))
2924 dst_release_immediate(&nrt6->dst);
2925 }
2926out_unlock:
2927 rcu_read_unlock();
2928 }
2929}
2930
2931static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
2932 struct sk_buff *skb, u32 mtu,
2933 bool confirm_neigh)
2934{
2935 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu,
2936 confirm_neigh);
2937}
2938
2939void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
2940 int oif, u32 mark, kuid_t uid)
2941{
2942 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2943 struct dst_entry *dst;
2944 struct flowi6 fl6 = {
2945 .flowi6_oif = oif,
2946 .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark),
2947 .daddr = iph->daddr,
2948 .saddr = iph->saddr,
2949 .flowlabel = ip6_flowinfo(iph),
2950 .flowi6_uid = uid,
2951 };
2952
2953 dst = ip6_route_output(net, NULL, &fl6);
2954 if (!dst->error)
2955 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu), true);
2956 dst_release(dst);
2957}
2958EXPORT_SYMBOL_GPL(ip6_update_pmtu);
2959
2960void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
2961{
2962 int oif = sk->sk_bound_dev_if;
2963 struct dst_entry *dst;
2964
2965 if (!oif && skb->dev)
2966 oif = l3mdev_master_ifindex(skb->dev);
2967
2968 ip6_update_pmtu(skb, sock_net(sk), mtu, oif, READ_ONCE(sk->sk_mark),
2969 sk->sk_uid);
2970
2971 dst = __sk_dst_get(sk);
2972 if (!dst || !dst->obsolete ||
2973 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
2974 return;
2975
2976 bh_lock_sock(sk);
2977 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
2978 ip6_datagram_dst_update(sk, false);
2979 bh_unlock_sock(sk);
2980}
2981EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
2982
2983void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
2984 const struct flowi6 *fl6)
2985{
2986#ifdef CONFIG_IPV6_SUBTREES
2987 struct ipv6_pinfo *np = inet6_sk(sk);
2988#endif
2989
2990 ip6_dst_store(sk, dst,
2991 ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr) ?
2992 &sk->sk_v6_daddr : NULL,
2993#ifdef CONFIG_IPV6_SUBTREES
2994 ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
2995 &np->saddr :
2996#endif
2997 NULL);
2998}
2999
3000static bool ip6_redirect_nh_match(const struct fib6_result *res,
3001 struct flowi6 *fl6,
3002 const struct in6_addr *gw,
3003 struct rt6_info **ret)
3004{
3005 const struct fib6_nh *nh = res->nh;
3006
3007 if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
3008 fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
3009 return false;
3010
3011 /* rt_cache's gateway might be different from its 'parent'
3012 * in the case of an ip redirect.
3013 * So we keep searching in the exception table if the gateway
3014 * is different.
3015 */
3016 if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
3017 struct rt6_info *rt_cache;
3018
3019 rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr);
3020 if (rt_cache &&
3021 ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
3022 *ret = rt_cache;
3023 return true;
3024 }
3025 return false;
3026 }
3027 return true;
3028}
3029
3030struct fib6_nh_rd_arg {
3031 struct fib6_result *res;
3032 struct flowi6 *fl6;
3033 const struct in6_addr *gw;
3034 struct rt6_info **ret;
3035};
3036
3037static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg)
3038{
3039 struct fib6_nh_rd_arg *arg = _arg;
3040
3041 arg->res->nh = nh;
3042 return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret);
3043}
3044
3045/* Handle redirects */
3046struct ip6rd_flowi {
3047 struct flowi6 fl6;
3048 struct in6_addr gateway;
3049};
3050
3051INDIRECT_CALLABLE_SCOPE struct rt6_info *__ip6_route_redirect(struct net *net,
3052 struct fib6_table *table,
3053 struct flowi6 *fl6,
3054 const struct sk_buff *skb,
3055 int flags)
3056{
3057 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
3058 struct rt6_info *ret = NULL;
3059 struct fib6_result res = {};
3060 struct fib6_nh_rd_arg arg = {
3061 .res = &res,
3062 .fl6 = fl6,
3063 .gw = &rdfl->gateway,
3064 .ret = &ret
3065 };
3066 struct fib6_info *rt;
3067 struct fib6_node *fn;
3068
3069 /* Get the "current" route for this destination and
3070 * check if the redirect has come from appropriate router.
3071 *
3072 * RFC 4861 specifies that redirects should only be
3073 * accepted if they come from the nexthop to the target.
3074 * Due to the way the routes are chosen, this notion
3075 * is a bit fuzzy and one might need to check all possible
3076 * routes.
3077 */
3078
3079 rcu_read_lock();
3080 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
3081restart:
3082 for_each_fib6_node_rt_rcu(fn) {
3083 res.f6i = rt;
3084 if (fib6_check_expired(rt))
3085 continue;
3086 if (rt->fib6_flags & RTF_REJECT)
3087 break;
3088 if (unlikely(rt->nh)) {
3089 if (nexthop_is_blackhole(rt->nh))
3090 continue;
3091 /* on match, res->nh is filled in and potentially ret */
3092 if (nexthop_for_each_fib6_nh(rt->nh,
3093 fib6_nh_redirect_match,
3094 &arg))
3095 goto out;
3096 } else {
3097 res.nh = rt->fib6_nh;
3098 if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway,
3099 &ret))
3100 goto out;
3101 }
3102 }
3103
3104 if (!rt)
3105 rt = net->ipv6.fib6_null_entry;
3106 else if (rt->fib6_flags & RTF_REJECT) {
3107 ret = net->ipv6.ip6_null_entry;
3108 goto out;
3109 }
3110
3111 if (rt == net->ipv6.fib6_null_entry) {
3112 fn = fib6_backtrack(fn, &fl6->saddr);
3113 if (fn)
3114 goto restart;
3115 }
3116
3117 res.f6i = rt;
3118 res.nh = rt->fib6_nh;
3119out:
3120 if (ret) {
3121 ip6_hold_safe(net, &ret);
3122 } else {
3123 res.fib6_flags = res.f6i->fib6_flags;
3124 res.fib6_type = res.f6i->fib6_type;
3125 ret = ip6_create_rt_rcu(&res);
3126 }
3127
3128 rcu_read_unlock();
3129
3130 trace_fib6_table_lookup(net, &res, table, fl6);
3131 return ret;
3132};
3133
3134static struct dst_entry *ip6_route_redirect(struct net *net,
3135 const struct flowi6 *fl6,
3136 const struct sk_buff *skb,
3137 const struct in6_addr *gateway)
3138{
3139 int flags = RT6_LOOKUP_F_HAS_SADDR;
3140 struct ip6rd_flowi rdfl;
3141
3142 rdfl.fl6 = *fl6;
3143 rdfl.gateway = *gateway;
3144
3145 return fib6_rule_lookup(net, &rdfl.fl6, skb,
3146 flags, __ip6_route_redirect);
3147}
3148
3149void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
3150 kuid_t uid)
3151{
3152 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
3153 struct dst_entry *dst;
3154 struct flowi6 fl6 = {
3155 .flowi6_iif = LOOPBACK_IFINDEX,
3156 .flowi6_oif = oif,
3157 .flowi6_mark = mark,
3158 .daddr = iph->daddr,
3159 .saddr = iph->saddr,
3160 .flowlabel = ip6_flowinfo(iph),
3161 .flowi6_uid = uid,
3162 };
3163
3164 dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
3165 rt6_do_redirect(dst, NULL, skb);
3166 dst_release(dst);
3167}
3168EXPORT_SYMBOL_GPL(ip6_redirect);
3169
3170void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
3171{
3172 const struct ipv6hdr *iph = ipv6_hdr(skb);
3173 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
3174 struct dst_entry *dst;
3175 struct flowi6 fl6 = {
3176 .flowi6_iif = LOOPBACK_IFINDEX,
3177 .flowi6_oif = oif,
3178 .daddr = msg->dest,
3179 .saddr = iph->daddr,
3180 .flowi6_uid = sock_net_uid(net, NULL),
3181 };
3182
3183 dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
3184 rt6_do_redirect(dst, NULL, skb);
3185 dst_release(dst);
3186}
3187
3188void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
3189{
3190 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if,
3191 READ_ONCE(sk->sk_mark), sk->sk_uid);
3192}
3193EXPORT_SYMBOL_GPL(ip6_sk_redirect);
3194
3195static unsigned int ip6_default_advmss(const struct dst_entry *dst)
3196{
3197 struct net_device *dev = dst->dev;
3198 unsigned int mtu = dst_mtu(dst);
3199 struct net *net;
3200
3201 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
3202
3203 rcu_read_lock();
3204
3205 net = dev_net_rcu(dev);
3206 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
3207 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
3208
3209 rcu_read_unlock();
3210
3211 /*
3212 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
3213 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
3214 * IPV6_MAXPLEN is also valid and means: "any MSS,
3215 * rely only on pmtu discovery"
3216 */
3217 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
3218 mtu = IPV6_MAXPLEN;
3219 return mtu;
3220}
3221
3222INDIRECT_CALLABLE_SCOPE unsigned int ip6_mtu(const struct dst_entry *dst)
3223{
3224 return ip6_dst_mtu_maybe_forward(dst, false);
3225}
3226EXPORT_INDIRECT_CALLABLE(ip6_mtu);
3227
3228/* MTU selection:
3229 * 1. mtu on route is locked - use it
3230 * 2. mtu from nexthop exception
3231 * 3. mtu from egress device
3232 *
3233 * based on ip6_dst_mtu_forward and exception logic of
3234 * rt6_find_cached_rt; called with rcu_read_lock
3235 */
3236u32 ip6_mtu_from_fib6(const struct fib6_result *res,
3237 const struct in6_addr *daddr,
3238 const struct in6_addr *saddr)
3239{
3240 const struct fib6_nh *nh = res->nh;
3241 struct fib6_info *f6i = res->f6i;
3242 struct inet6_dev *idev;
3243 struct rt6_info *rt;
3244 u32 mtu = 0;
3245
3246 if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
3247 mtu = f6i->fib6_pmtu;
3248 if (mtu)
3249 goto out;
3250 }
3251
3252 rt = rt6_find_cached_rt(res, daddr, saddr);
3253 if (unlikely(rt)) {
3254 mtu = dst_metric_raw(&rt->dst, RTAX_MTU);
3255 } else {
3256 struct net_device *dev = nh->fib_nh_dev;
3257
3258 mtu = IPV6_MIN_MTU;
3259 idev = __in6_dev_get(dev);
3260 if (idev)
3261 mtu = max_t(u32, mtu, READ_ONCE(idev->cnf.mtu6));
3262 }
3263
3264 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3265out:
3266 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
3267}
3268
3269struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
3270 struct flowi6 *fl6)
3271{
3272 struct dst_entry *dst;
3273 struct rt6_info *rt;
3274 struct inet6_dev *idev = in6_dev_get(dev);
3275 struct net *net = dev_net(dev);
3276
3277 if (unlikely(!idev))
3278 return ERR_PTR(-ENODEV);
3279
3280 rt = ip6_dst_alloc(net, dev, 0);
3281 if (unlikely(!rt)) {
3282 in6_dev_put(idev);
3283 dst = ERR_PTR(-ENOMEM);
3284 goto out;
3285 }
3286
3287 rt->dst.input = ip6_input;
3288 rt->dst.output = ip6_output;
3289 rt->rt6i_gateway = fl6->daddr;
3290 rt->rt6i_dst.addr = fl6->daddr;
3291 rt->rt6i_dst.plen = 128;
3292 rt->rt6i_idev = idev;
3293 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
3294
3295 /* Add this dst into uncached_list so that rt6_disable_ip() can
3296 * do proper release of the net_device
3297 */
3298 rt6_uncached_list_add(rt);
3299
3300 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
3301
3302out:
3303 return dst;
3304}
3305
3306static void ip6_dst_gc(struct dst_ops *ops)
3307{
3308 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
3309 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
3310 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
3311 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
3312 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
3313 unsigned int val;
3314 int entries;
3315
3316 if (time_after(rt_last_gc + rt_min_interval, jiffies))
3317 goto out;
3318
3319 fib6_run_gc(atomic_inc_return(&net->ipv6.ip6_rt_gc_expire), net, true);
3320 entries = dst_entries_get_slow(ops);
3321 if (entries < ops->gc_thresh)
3322 atomic_set(&net->ipv6.ip6_rt_gc_expire, rt_gc_timeout >> 1);
3323out:
3324 val = atomic_read(&net->ipv6.ip6_rt_gc_expire);
3325 atomic_set(&net->ipv6.ip6_rt_gc_expire, val - (val >> rt_elasticity));
3326}
3327
3328static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
3329 const struct in6_addr *gw_addr, u32 tbid,
3330 int flags, struct fib6_result *res)
3331{
3332 struct flowi6 fl6 = {
3333 .flowi6_oif = cfg->fc_ifindex,
3334 .daddr = *gw_addr,
3335 .saddr = cfg->fc_prefsrc,
3336 };
3337 struct fib6_table *table;
3338 int err;
3339
3340 table = fib6_get_table(net, tbid);
3341 if (!table)
3342 return -EINVAL;
3343
3344 if (!ipv6_addr_any(&cfg->fc_prefsrc))
3345 flags |= RT6_LOOKUP_F_HAS_SADDR;
3346
3347 flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
3348
3349 err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags);
3350 if (!err && res->f6i != net->ipv6.fib6_null_entry)
3351 fib6_select_path(net, res, &fl6, cfg->fc_ifindex,
3352 cfg->fc_ifindex != 0, NULL, flags);
3353
3354 return err;
3355}
3356
3357static int ip6_route_check_nh_onlink(struct net *net,
3358 struct fib6_config *cfg,
3359 const struct net_device *dev,
3360 struct netlink_ext_ack *extack)
3361{
3362 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
3363 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3364 struct fib6_result res = {};
3365 int err;
3366
3367 err = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0, &res);
3368 if (!err && !(res.fib6_flags & RTF_REJECT) &&
3369 /* ignore match if it is the default route */
3370 !ipv6_addr_any(&res.f6i->fib6_dst.addr) &&
3371 (res.fib6_type != RTN_UNICAST || dev != res.nh->fib_nh_dev)) {
3372 NL_SET_ERR_MSG(extack,
3373 "Nexthop has invalid gateway or device mismatch");
3374 err = -EINVAL;
3375 }
3376
3377 return err;
3378}
3379
3380static int ip6_route_check_nh(struct net *net,
3381 struct fib6_config *cfg,
3382 struct net_device **_dev,
3383 netdevice_tracker *dev_tracker,
3384 struct inet6_dev **idev)
3385{
3386 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3387 struct net_device *dev = _dev ? *_dev : NULL;
3388 int flags = RT6_LOOKUP_F_IFACE;
3389 struct fib6_result res = {};
3390 int err = -EHOSTUNREACH;
3391
3392 if (cfg->fc_table) {
3393 err = ip6_nh_lookup_table(net, cfg, gw_addr,
3394 cfg->fc_table, flags, &res);
3395 /* gw_addr can not require a gateway or resolve to a reject
3396 * route. If a device is given, it must match the result.
3397 */
3398 if (err || res.fib6_flags & RTF_REJECT ||
3399 res.nh->fib_nh_gw_family ||
3400 (dev && dev != res.nh->fib_nh_dev))
3401 err = -EHOSTUNREACH;
3402 }
3403
3404 if (err < 0) {
3405 struct flowi6 fl6 = {
3406 .flowi6_oif = cfg->fc_ifindex,
3407 .daddr = *gw_addr,
3408 };
3409
3410 err = fib6_lookup(net, cfg->fc_ifindex, &fl6, &res, flags);
3411 if (err || res.fib6_flags & RTF_REJECT ||
3412 res.nh->fib_nh_gw_family)
3413 err = -EHOSTUNREACH;
3414
3415 if (err)
3416 return err;
3417
3418 fib6_select_path(net, &res, &fl6, cfg->fc_ifindex,
3419 cfg->fc_ifindex != 0, NULL, flags);
3420 }
3421
3422 err = 0;
3423 if (dev) {
3424 if (dev != res.nh->fib_nh_dev)
3425 err = -EHOSTUNREACH;
3426 } else {
3427 *_dev = dev = res.nh->fib_nh_dev;
3428 netdev_hold(dev, dev_tracker, GFP_ATOMIC);
3429 *idev = in6_dev_get(dev);
3430 }
3431
3432 return err;
3433}
3434
3435static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
3436 struct net_device **_dev,
3437 netdevice_tracker *dev_tracker,
3438 struct inet6_dev **idev,
3439 struct netlink_ext_ack *extack)
3440{
3441 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3442 int gwa_type = ipv6_addr_type(gw_addr);
3443 bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
3444 const struct net_device *dev = *_dev;
3445 bool need_addr_check = !dev;
3446 int err = -EINVAL;
3447
3448 /* if gw_addr is local we will fail to detect this in case
3449 * address is still TENTATIVE (DAD in progress). rt6_lookup()
3450 * will return already-added prefix route via interface that
3451 * prefix route was assigned to, which might be non-loopback.
3452 */
3453 if (dev &&
3454 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3455 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3456 goto out;
3457 }
3458
3459 if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
3460 /* IPv6 strictly inhibits using not link-local
3461 * addresses as nexthop address.
3462 * Otherwise, router will not able to send redirects.
3463 * It is very good, but in some (rare!) circumstances
3464 * (SIT, PtP, NBMA NOARP links) it is handy to allow
3465 * some exceptions. --ANK
3466 * We allow IPv4-mapped nexthops to support RFC4798-type
3467 * addressing
3468 */
3469 if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
3470 NL_SET_ERR_MSG(extack, "Invalid gateway address");
3471 goto out;
3472 }
3473
3474 rcu_read_lock();
3475
3476 if (cfg->fc_flags & RTNH_F_ONLINK)
3477 err = ip6_route_check_nh_onlink(net, cfg, dev, extack);
3478 else
3479 err = ip6_route_check_nh(net, cfg, _dev, dev_tracker,
3480 idev);
3481
3482 rcu_read_unlock();
3483
3484 if (err)
3485 goto out;
3486 }
3487
3488 /* reload in case device was changed */
3489 dev = *_dev;
3490
3491 err = -EINVAL;
3492 if (!dev) {
3493 NL_SET_ERR_MSG(extack, "Egress device not specified");
3494 goto out;
3495 } else if (dev->flags & IFF_LOOPBACK) {
3496 NL_SET_ERR_MSG(extack,
3497 "Egress device can not be loopback device for this route");
3498 goto out;
3499 }
3500
3501 /* if we did not check gw_addr above, do so now that the
3502 * egress device has been resolved.
3503 */
3504 if (need_addr_check &&
3505 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3506 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3507 goto out;
3508 }
3509
3510 err = 0;
3511out:
3512 return err;
3513}
3514
3515static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type)
3516{
3517 if ((flags & RTF_REJECT) ||
3518 (dev && (dev->flags & IFF_LOOPBACK) &&
3519 !(addr_type & IPV6_ADDR_LOOPBACK) &&
3520 !(flags & (RTF_ANYCAST | RTF_LOCAL))))
3521 return true;
3522
3523 return false;
3524}
3525
3526int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
3527 struct fib6_config *cfg, gfp_t gfp_flags,
3528 struct netlink_ext_ack *extack)
3529{
3530 netdevice_tracker *dev_tracker = &fib6_nh->fib_nh_dev_tracker;
3531 struct net_device *dev = NULL;
3532 struct inet6_dev *idev = NULL;
3533 int addr_type;
3534 int err;
3535
3536 fib6_nh->fib_nh_family = AF_INET6;
3537#ifdef CONFIG_IPV6_ROUTER_PREF
3538 fib6_nh->last_probe = jiffies;
3539#endif
3540 if (cfg->fc_is_fdb) {
3541 fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
3542 fib6_nh->fib_nh_gw_family = AF_INET6;
3543 return 0;
3544 }
3545
3546 err = -ENODEV;
3547 if (cfg->fc_ifindex) {
3548 dev = netdev_get_by_index(net, cfg->fc_ifindex,
3549 dev_tracker, gfp_flags);
3550 if (!dev)
3551 goto out;
3552 idev = in6_dev_get(dev);
3553 if (!idev)
3554 goto out;
3555 }
3556
3557 if (cfg->fc_flags & RTNH_F_ONLINK) {
3558 if (!dev) {
3559 NL_SET_ERR_MSG(extack,
3560 "Nexthop device required for onlink");
3561 goto out;
3562 }
3563
3564 if (!(dev->flags & IFF_UP)) {
3565 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3566 err = -ENETDOWN;
3567 goto out;
3568 }
3569
3570 fib6_nh->fib_nh_flags |= RTNH_F_ONLINK;
3571 }
3572
3573 fib6_nh->fib_nh_weight = 1;
3574
3575 /* We cannot add true routes via loopback here,
3576 * they would result in kernel looping; promote them to reject routes
3577 */
3578 addr_type = ipv6_addr_type(&cfg->fc_dst);
3579 if (fib6_is_reject(cfg->fc_flags, dev, addr_type)) {
3580 /* hold loopback dev/idev if we haven't done so. */
3581 if (dev != net->loopback_dev) {
3582 if (dev) {
3583 netdev_put(dev, dev_tracker);
3584 in6_dev_put(idev);
3585 }
3586 dev = net->loopback_dev;
3587 netdev_hold(dev, dev_tracker, gfp_flags);
3588 idev = in6_dev_get(dev);
3589 if (!idev) {
3590 err = -ENODEV;
3591 goto out;
3592 }
3593 }
3594 goto pcpu_alloc;
3595 }
3596
3597 if (cfg->fc_flags & RTF_GATEWAY) {
3598 err = ip6_validate_gw(net, cfg, &dev, dev_tracker,
3599 &idev, extack);
3600 if (err)
3601 goto out;
3602
3603 fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
3604 fib6_nh->fib_nh_gw_family = AF_INET6;
3605 }
3606
3607 err = -ENODEV;
3608 if (!dev)
3609 goto out;
3610
3611 if (!idev || idev->cnf.disable_ipv6) {
3612 NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
3613 err = -EACCES;
3614 goto out;
3615 }
3616
3617 if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) {
3618 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3619 err = -ENETDOWN;
3620 goto out;
3621 }
3622
3623 if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
3624 !netif_carrier_ok(dev))
3625 fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
3626
3627 err = fib_nh_common_init(net, &fib6_nh->nh_common, cfg->fc_encap,
3628 cfg->fc_encap_type, cfg, gfp_flags, extack);
3629 if (err)
3630 goto out;
3631
3632pcpu_alloc:
3633 fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags);
3634 if (!fib6_nh->rt6i_pcpu) {
3635 err = -ENOMEM;
3636 goto out;
3637 }
3638
3639 fib6_nh->fib_nh_dev = dev;
3640 fib6_nh->fib_nh_oif = dev->ifindex;
3641 err = 0;
3642out:
3643 if (idev)
3644 in6_dev_put(idev);
3645
3646 if (err) {
3647 lwtstate_put(fib6_nh->fib_nh_lws);
3648 fib6_nh->fib_nh_lws = NULL;
3649 netdev_put(dev, dev_tracker);
3650 }
3651
3652 return err;
3653}
3654
3655void fib6_nh_release(struct fib6_nh *fib6_nh)
3656{
3657 struct rt6_exception_bucket *bucket;
3658
3659 rcu_read_lock();
3660
3661 fib6_nh_flush_exceptions(fib6_nh, NULL);
3662 bucket = fib6_nh_get_excptn_bucket(fib6_nh, NULL);
3663 if (bucket) {
3664 rcu_assign_pointer(fib6_nh->rt6i_exception_bucket, NULL);
3665 kfree(bucket);
3666 }
3667
3668 rcu_read_unlock();
3669
3670 fib6_nh_release_dsts(fib6_nh);
3671 free_percpu(fib6_nh->rt6i_pcpu);
3672
3673 fib_nh_common_release(&fib6_nh->nh_common);
3674}
3675
3676void fib6_nh_release_dsts(struct fib6_nh *fib6_nh)
3677{
3678 int cpu;
3679
3680 if (!fib6_nh->rt6i_pcpu)
3681 return;
3682
3683 for_each_possible_cpu(cpu) {
3684 struct rt6_info *pcpu_rt, **ppcpu_rt;
3685
3686 ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu);
3687 pcpu_rt = xchg(ppcpu_rt, NULL);
3688 if (pcpu_rt) {
3689 dst_dev_put(&pcpu_rt->dst);
3690 dst_release(&pcpu_rt->dst);
3691 }
3692 }
3693}
3694
3695static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
3696 gfp_t gfp_flags,
3697 struct netlink_ext_ack *extack)
3698{
3699 struct net *net = cfg->fc_nlinfo.nl_net;
3700 struct fib6_info *rt = NULL;
3701 struct nexthop *nh = NULL;
3702 struct fib6_table *table;
3703 struct fib6_nh *fib6_nh;
3704 int err = -EINVAL;
3705 int addr_type;
3706
3707 /* RTF_PCPU is an internal flag; can not be set by userspace */
3708 if (cfg->fc_flags & RTF_PCPU) {
3709 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
3710 goto out;
3711 }
3712
3713 /* RTF_CACHE is an internal flag; can not be set by userspace */
3714 if (cfg->fc_flags & RTF_CACHE) {
3715 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
3716 goto out;
3717 }
3718
3719 if (cfg->fc_type > RTN_MAX) {
3720 NL_SET_ERR_MSG(extack, "Invalid route type");
3721 goto out;
3722 }
3723
3724 if (cfg->fc_dst_len > 128) {
3725 NL_SET_ERR_MSG(extack, "Invalid prefix length");
3726 goto out;
3727 }
3728 if (cfg->fc_src_len > 128) {
3729 NL_SET_ERR_MSG(extack, "Invalid source address length");
3730 goto out;
3731 }
3732#ifndef CONFIG_IPV6_SUBTREES
3733 if (cfg->fc_src_len) {
3734 NL_SET_ERR_MSG(extack,
3735 "Specifying source address requires IPV6_SUBTREES to be enabled");
3736 goto out;
3737 }
3738#endif
3739 if (cfg->fc_nh_id) {
3740 nh = nexthop_find_by_id(net, cfg->fc_nh_id);
3741 if (!nh) {
3742 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
3743 goto out;
3744 }
3745 err = fib6_check_nexthop(nh, cfg, extack);
3746 if (err)
3747 goto out;
3748 }
3749
3750 err = -ENOBUFS;
3751 if (cfg->fc_nlinfo.nlh &&
3752 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
3753 table = fib6_get_table(net, cfg->fc_table);
3754 if (!table) {
3755 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
3756 table = fib6_new_table(net, cfg->fc_table);
3757 }
3758 } else {
3759 table = fib6_new_table(net, cfg->fc_table);
3760 }
3761
3762 if (!table)
3763 goto out;
3764
3765 err = -ENOMEM;
3766 rt = fib6_info_alloc(gfp_flags, !nh);
3767 if (!rt)
3768 goto out;
3769
3770 rt->fib6_metrics = ip_fib_metrics_init(cfg->fc_mx, cfg->fc_mx_len,
3771 extack);
3772 if (IS_ERR(rt->fib6_metrics)) {
3773 err = PTR_ERR(rt->fib6_metrics);
3774 /* Do not leave garbage there. */
3775 rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
3776 goto out_free;
3777 }
3778
3779 if (cfg->fc_flags & RTF_ADDRCONF)
3780 rt->dst_nocount = true;
3781
3782 if (cfg->fc_flags & RTF_EXPIRES)
3783 fib6_set_expires(rt, jiffies +
3784 clock_t_to_jiffies(cfg->fc_expires));
3785
3786 if (cfg->fc_protocol == RTPROT_UNSPEC)
3787 cfg->fc_protocol = RTPROT_BOOT;
3788 rt->fib6_protocol = cfg->fc_protocol;
3789
3790 rt->fib6_table = table;
3791 rt->fib6_metric = cfg->fc_metric;
3792 rt->fib6_type = cfg->fc_type ? : RTN_UNICAST;
3793 rt->fib6_flags = cfg->fc_flags & ~RTF_GATEWAY;
3794
3795 ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
3796 rt->fib6_dst.plen = cfg->fc_dst_len;
3797
3798#ifdef CONFIG_IPV6_SUBTREES
3799 ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3800 rt->fib6_src.plen = cfg->fc_src_len;
3801#endif
3802 if (nh) {
3803 if (rt->fib6_src.plen) {
3804 NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
3805 goto out_free;
3806 }
3807 if (!nexthop_get(nh)) {
3808 NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
3809 goto out_free;
3810 }
3811 rt->nh = nh;
3812 fib6_nh = nexthop_fib6_nh(rt->nh);
3813 } else {
3814 err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
3815 if (err)
3816 goto out;
3817
3818 fib6_nh = rt->fib6_nh;
3819
3820 /* We cannot add true routes via loopback here, they would
3821 * result in kernel looping; promote them to reject routes
3822 */
3823 addr_type = ipv6_addr_type(&cfg->fc_dst);
3824 if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev,
3825 addr_type))
3826 rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP;
3827 }
3828
3829 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
3830 struct net_device *dev = fib6_nh->fib_nh_dev;
3831
3832 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3833 NL_SET_ERR_MSG(extack, "Invalid source address");
3834 err = -EINVAL;
3835 goto out;
3836 }
3837 rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3838 rt->fib6_prefsrc.plen = 128;
3839 } else
3840 rt->fib6_prefsrc.plen = 0;
3841
3842 return rt;
3843out:
3844 fib6_info_release(rt);
3845 return ERR_PTR(err);
3846out_free:
3847 ip_fib_metrics_put(rt->fib6_metrics);
3848 kfree(rt);
3849 return ERR_PTR(err);
3850}
3851
3852int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
3853 struct netlink_ext_ack *extack)
3854{
3855 struct fib6_info *rt;
3856 int err;
3857
3858 rt = ip6_route_info_create(cfg, gfp_flags, extack);
3859 if (IS_ERR(rt))
3860 return PTR_ERR(rt);
3861
3862 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3863 fib6_info_release(rt);
3864
3865 return err;
3866}
3867
3868static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
3869{
3870 struct net *net = info->nl_net;
3871 struct fib6_table *table;
3872 int err;
3873
3874 if (rt == net->ipv6.fib6_null_entry) {
3875 err = -ENOENT;
3876 goto out;
3877 }
3878
3879 table = rt->fib6_table;
3880 spin_lock_bh(&table->tb6_lock);
3881 err = fib6_del(rt, info);
3882 spin_unlock_bh(&table->tb6_lock);
3883
3884out:
3885 fib6_info_release(rt);
3886 return err;
3887}
3888
3889int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify)
3890{
3891 struct nl_info info = {
3892 .nl_net = net,
3893 .skip_notify = skip_notify
3894 };
3895
3896 return __ip6_del_rt(rt, &info);
3897}
3898
3899static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
3900{
3901 struct nl_info *info = &cfg->fc_nlinfo;
3902 struct net *net = info->nl_net;
3903 struct sk_buff *skb = NULL;
3904 struct fib6_table *table;
3905 int err = -ENOENT;
3906
3907 if (rt == net->ipv6.fib6_null_entry)
3908 goto out_put;
3909 table = rt->fib6_table;
3910 spin_lock_bh(&table->tb6_lock);
3911
3912 if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
3913 struct fib6_info *sibling, *next_sibling;
3914 struct fib6_node *fn;
3915
3916 /* prefer to send a single notification with all hops */
3917 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3918 if (skb) {
3919 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3920
3921 if (rt6_fill_node(net, skb, rt, NULL,
3922 NULL, NULL, 0, RTM_DELROUTE,
3923 info->portid, seq, 0) < 0) {
3924 kfree_skb(skb);
3925 skb = NULL;
3926 } else
3927 info->skip_notify = 1;
3928 }
3929
3930 /* 'rt' points to the first sibling route. If it is not the
3931 * leaf, then we do not need to send a notification. Otherwise,
3932 * we need to check if the last sibling has a next route or not
3933 * and emit a replace or delete notification, respectively.
3934 */
3935 info->skip_notify_kernel = 1;
3936 fn = rcu_dereference_protected(rt->fib6_node,
3937 lockdep_is_held(&table->tb6_lock));
3938 if (rcu_access_pointer(fn->leaf) == rt) {
3939 struct fib6_info *last_sibling, *replace_rt;
3940
3941 last_sibling = list_last_entry(&rt->fib6_siblings,
3942 struct fib6_info,
3943 fib6_siblings);
3944 replace_rt = rcu_dereference_protected(
3945 last_sibling->fib6_next,
3946 lockdep_is_held(&table->tb6_lock));
3947 if (replace_rt)
3948 call_fib6_entry_notifiers_replace(net,
3949 replace_rt);
3950 else
3951 call_fib6_multipath_entry_notifiers(net,
3952 FIB_EVENT_ENTRY_DEL,
3953 rt, rt->fib6_nsiblings,
3954 NULL);
3955 }
3956 list_for_each_entry_safe(sibling, next_sibling,
3957 &rt->fib6_siblings,
3958 fib6_siblings) {
3959 err = fib6_del(sibling, info);
3960 if (err)
3961 goto out_unlock;
3962 }
3963 }
3964
3965 err = fib6_del(rt, info);
3966out_unlock:
3967 spin_unlock_bh(&table->tb6_lock);
3968out_put:
3969 fib6_info_release(rt);
3970
3971 if (skb) {
3972 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3973 info->nlh, gfp_any());
3974 }
3975 return err;
3976}
3977
3978static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
3979{
3980 int rc = -ESRCH;
3981
3982 if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
3983 goto out;
3984
3985 if (cfg->fc_flags & RTF_GATEWAY &&
3986 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
3987 goto out;
3988
3989 rc = rt6_remove_exception_rt(rt);
3990out:
3991 return rc;
3992}
3993
3994static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt,
3995 struct fib6_nh *nh)
3996{
3997 struct fib6_result res = {
3998 .f6i = rt,
3999 .nh = nh,
4000 };
4001 struct rt6_info *rt_cache;
4002
4003 rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src);
4004 if (rt_cache)
4005 return __ip6_del_cached_rt(rt_cache, cfg);
4006
4007 return 0;
4008}
4009
4010struct fib6_nh_del_cached_rt_arg {
4011 struct fib6_config *cfg;
4012 struct fib6_info *f6i;
4013};
4014
4015static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg)
4016{
4017 struct fib6_nh_del_cached_rt_arg *arg = _arg;
4018 int rc;
4019
4020 rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh);
4021 return rc != -ESRCH ? rc : 0;
4022}
4023
4024static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i)
4025{
4026 struct fib6_nh_del_cached_rt_arg arg = {
4027 .cfg = cfg,
4028 .f6i = f6i
4029 };
4030
4031 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg);
4032}
4033
4034static int ip6_route_del(struct fib6_config *cfg,
4035 struct netlink_ext_ack *extack)
4036{
4037 struct fib6_table *table;
4038 struct fib6_info *rt;
4039 struct fib6_node *fn;
4040 int err = -ESRCH;
4041
4042 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
4043 if (!table) {
4044 NL_SET_ERR_MSG(extack, "FIB table does not exist");
4045 return err;
4046 }
4047
4048 rcu_read_lock();
4049
4050 fn = fib6_locate(&table->tb6_root,
4051 &cfg->fc_dst, cfg->fc_dst_len,
4052 &cfg->fc_src, cfg->fc_src_len,
4053 !(cfg->fc_flags & RTF_CACHE));
4054
4055 if (fn) {
4056 for_each_fib6_node_rt_rcu(fn) {
4057 struct fib6_nh *nh;
4058
4059 if (rt->nh && cfg->fc_nh_id &&
4060 rt->nh->id != cfg->fc_nh_id)
4061 continue;
4062
4063 if (cfg->fc_flags & RTF_CACHE) {
4064 int rc = 0;
4065
4066 if (rt->nh) {
4067 rc = ip6_del_cached_rt_nh(cfg, rt);
4068 } else if (cfg->fc_nh_id) {
4069 continue;
4070 } else {
4071 nh = rt->fib6_nh;
4072 rc = ip6_del_cached_rt(cfg, rt, nh);
4073 }
4074 if (rc != -ESRCH) {
4075 rcu_read_unlock();
4076 return rc;
4077 }
4078 continue;
4079 }
4080
4081 if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
4082 continue;
4083 if (cfg->fc_protocol &&
4084 cfg->fc_protocol != rt->fib6_protocol)
4085 continue;
4086
4087 if (rt->nh) {
4088 if (!fib6_info_hold_safe(rt))
4089 continue;
4090 rcu_read_unlock();
4091
4092 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
4093 }
4094 if (cfg->fc_nh_id)
4095 continue;
4096
4097 nh = rt->fib6_nh;
4098 if (cfg->fc_ifindex &&
4099 (!nh->fib_nh_dev ||
4100 nh->fib_nh_dev->ifindex != cfg->fc_ifindex))
4101 continue;
4102 if (cfg->fc_flags & RTF_GATEWAY &&
4103 !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6))
4104 continue;
4105 if (!fib6_info_hold_safe(rt))
4106 continue;
4107 rcu_read_unlock();
4108
4109 /* if gateway was specified only delete the one hop */
4110 if (cfg->fc_flags & RTF_GATEWAY)
4111 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
4112
4113 return __ip6_del_rt_siblings(rt, cfg);
4114 }
4115 }
4116 rcu_read_unlock();
4117
4118 return err;
4119}
4120
4121static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
4122{
4123 struct netevent_redirect netevent;
4124 struct rt6_info *rt, *nrt = NULL;
4125 struct fib6_result res = {};
4126 struct ndisc_options ndopts;
4127 struct inet6_dev *in6_dev;
4128 struct neighbour *neigh;
4129 struct rd_msg *msg;
4130 int optlen, on_link;
4131 u8 *lladdr;
4132
4133 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
4134 optlen -= sizeof(*msg);
4135
4136 if (optlen < 0) {
4137 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
4138 return;
4139 }
4140
4141 msg = (struct rd_msg *)icmp6_hdr(skb);
4142
4143 if (ipv6_addr_is_multicast(&msg->dest)) {
4144 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
4145 return;
4146 }
4147
4148 on_link = 0;
4149 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
4150 on_link = 1;
4151 } else if (ipv6_addr_type(&msg->target) !=
4152 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
4153 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
4154 return;
4155 }
4156
4157 in6_dev = __in6_dev_get(skb->dev);
4158 if (!in6_dev)
4159 return;
4160 if (READ_ONCE(in6_dev->cnf.forwarding) ||
4161 !READ_ONCE(in6_dev->cnf.accept_redirects))
4162 return;
4163
4164 /* RFC2461 8.1:
4165 * The IP source address of the Redirect MUST be the same as the current
4166 * first-hop router for the specified ICMP Destination Address.
4167 */
4168
4169 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
4170 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
4171 return;
4172 }
4173
4174 lladdr = NULL;
4175 if (ndopts.nd_opts_tgt_lladdr) {
4176 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
4177 skb->dev);
4178 if (!lladdr) {
4179 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
4180 return;
4181 }
4182 }
4183
4184 rt = dst_rt6_info(dst);
4185 if (rt->rt6i_flags & RTF_REJECT) {
4186 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
4187 return;
4188 }
4189
4190 /* Redirect received -> path was valid.
4191 * Look, redirects are sent only in response to data packets,
4192 * so that this nexthop apparently is reachable. --ANK
4193 */
4194 dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
4195
4196 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
4197 if (!neigh)
4198 return;
4199
4200 /*
4201 * We have finally decided to accept it.
4202 */
4203
4204 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
4205 NEIGH_UPDATE_F_WEAK_OVERRIDE|
4206 NEIGH_UPDATE_F_OVERRIDE|
4207 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
4208 NEIGH_UPDATE_F_ISROUTER)),
4209 NDISC_REDIRECT, &ndopts);
4210
4211 rcu_read_lock();
4212 res.f6i = rcu_dereference(rt->from);
4213 if (!res.f6i)
4214 goto out;
4215
4216 if (res.f6i->nh) {
4217 struct fib6_nh_match_arg arg = {
4218 .dev = dst->dev,
4219 .gw = &rt->rt6i_gateway,
4220 };
4221
4222 nexthop_for_each_fib6_nh(res.f6i->nh,
4223 fib6_nh_find_match, &arg);
4224
4225 /* fib6_info uses a nexthop that does not have fib6_nh
4226 * using the dst->dev. Should be impossible
4227 */
4228 if (!arg.match)
4229 goto out;
4230 res.nh = arg.match;
4231 } else {
4232 res.nh = res.f6i->fib6_nh;
4233 }
4234
4235 res.fib6_flags = res.f6i->fib6_flags;
4236 res.fib6_type = res.f6i->fib6_type;
4237 nrt = ip6_rt_cache_alloc(&res, &msg->dest, NULL);
4238 if (!nrt)
4239 goto out;
4240
4241 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
4242 if (on_link)
4243 nrt->rt6i_flags &= ~RTF_GATEWAY;
4244
4245 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
4246
4247 /* rt6_insert_exception() will take care of duplicated exceptions */
4248 if (rt6_insert_exception(nrt, &res)) {
4249 dst_release_immediate(&nrt->dst);
4250 goto out;
4251 }
4252
4253 netevent.old = &rt->dst;
4254 netevent.new = &nrt->dst;
4255 netevent.daddr = &msg->dest;
4256 netevent.neigh = neigh;
4257 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
4258
4259out:
4260 rcu_read_unlock();
4261 neigh_release(neigh);
4262}
4263
4264#ifdef CONFIG_IPV6_ROUTE_INFO
4265static struct fib6_info *rt6_get_route_info(struct net *net,
4266 const struct in6_addr *prefix, int prefixlen,
4267 const struct in6_addr *gwaddr,
4268 struct net_device *dev)
4269{
4270 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
4271 int ifindex = dev->ifindex;
4272 struct fib6_node *fn;
4273 struct fib6_info *rt = NULL;
4274 struct fib6_table *table;
4275
4276 table = fib6_get_table(net, tb_id);
4277 if (!table)
4278 return NULL;
4279
4280 rcu_read_lock();
4281 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
4282 if (!fn)
4283 goto out;
4284
4285 for_each_fib6_node_rt_rcu(fn) {
4286 /* these routes do not use nexthops */
4287 if (rt->nh)
4288 continue;
4289 if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex)
4290 continue;
4291 if (!(rt->fib6_flags & RTF_ROUTEINFO) ||
4292 !rt->fib6_nh->fib_nh_gw_family)
4293 continue;
4294 if (!ipv6_addr_equal(&rt->fib6_nh->fib_nh_gw6, gwaddr))
4295 continue;
4296 if (!fib6_info_hold_safe(rt))
4297 continue;
4298 break;
4299 }
4300out:
4301 rcu_read_unlock();
4302 return rt;
4303}
4304
4305static struct fib6_info *rt6_add_route_info(struct net *net,
4306 const struct in6_addr *prefix, int prefixlen,
4307 const struct in6_addr *gwaddr,
4308 struct net_device *dev,
4309 unsigned int pref)
4310{
4311 struct fib6_config cfg = {
4312 .fc_metric = IP6_RT_PRIO_USER,
4313 .fc_ifindex = dev->ifindex,
4314 .fc_dst_len = prefixlen,
4315 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
4316 RTF_UP | RTF_PREF(pref),
4317 .fc_protocol = RTPROT_RA,
4318 .fc_type = RTN_UNICAST,
4319 .fc_nlinfo.portid = 0,
4320 .fc_nlinfo.nlh = NULL,
4321 .fc_nlinfo.nl_net = net,
4322 };
4323
4324 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
4325 cfg.fc_dst = *prefix;
4326 cfg.fc_gateway = *gwaddr;
4327
4328 /* We should treat it as a default route if prefix length is 0. */
4329 if (!prefixlen)
4330 cfg.fc_flags |= RTF_DEFAULT;
4331
4332 ip6_route_add(&cfg, GFP_ATOMIC, NULL);
4333
4334 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
4335}
4336#endif
4337
4338struct fib6_info *rt6_get_dflt_router(struct net *net,
4339 const struct in6_addr *addr,
4340 struct net_device *dev)
4341{
4342 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
4343 struct fib6_info *rt;
4344 struct fib6_table *table;
4345
4346 table = fib6_get_table(net, tb_id);
4347 if (!table)
4348 return NULL;
4349
4350 rcu_read_lock();
4351 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4352 struct fib6_nh *nh;
4353
4354 /* RA routes do not use nexthops */
4355 if (rt->nh)
4356 continue;
4357
4358 nh = rt->fib6_nh;
4359 if (dev == nh->fib_nh_dev &&
4360 ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
4361 ipv6_addr_equal(&nh->fib_nh_gw6, addr))
4362 break;
4363 }
4364 if (rt && !fib6_info_hold_safe(rt))
4365 rt = NULL;
4366 rcu_read_unlock();
4367 return rt;
4368}
4369
4370struct fib6_info *rt6_add_dflt_router(struct net *net,
4371 const struct in6_addr *gwaddr,
4372 struct net_device *dev,
4373 unsigned int pref,
4374 u32 defrtr_usr_metric,
4375 int lifetime)
4376{
4377 struct fib6_config cfg = {
4378 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
4379 .fc_metric = defrtr_usr_metric,
4380 .fc_ifindex = dev->ifindex,
4381 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
4382 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
4383 .fc_protocol = RTPROT_RA,
4384 .fc_type = RTN_UNICAST,
4385 .fc_nlinfo.portid = 0,
4386 .fc_nlinfo.nlh = NULL,
4387 .fc_nlinfo.nl_net = net,
4388 .fc_expires = jiffies_to_clock_t(lifetime * HZ),
4389 };
4390
4391 cfg.fc_gateway = *gwaddr;
4392
4393 if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
4394 struct fib6_table *table;
4395
4396 table = fib6_get_table(dev_net(dev), cfg.fc_table);
4397 if (table)
4398 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
4399 }
4400
4401 return rt6_get_dflt_router(net, gwaddr, dev);
4402}
4403
4404static void __rt6_purge_dflt_routers(struct net *net,
4405 struct fib6_table *table)
4406{
4407 struct fib6_info *rt;
4408
4409restart:
4410 rcu_read_lock();
4411 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4412 struct net_device *dev = fib6_info_nh_dev(rt);
4413 struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
4414
4415 if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
4416 (!idev || idev->cnf.accept_ra != 2) &&
4417 fib6_info_hold_safe(rt)) {
4418 rcu_read_unlock();
4419 ip6_del_rt(net, rt, false);
4420 goto restart;
4421 }
4422 }
4423 rcu_read_unlock();
4424
4425 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
4426}
4427
4428void rt6_purge_dflt_routers(struct net *net)
4429{
4430 struct fib6_table *table;
4431 struct hlist_head *head;
4432 unsigned int h;
4433
4434 rcu_read_lock();
4435
4436 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
4437 head = &net->ipv6.fib_table_hash[h];
4438 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
4439 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
4440 __rt6_purge_dflt_routers(net, table);
4441 }
4442 }
4443
4444 rcu_read_unlock();
4445}
4446
4447static void rtmsg_to_fib6_config(struct net *net,
4448 struct in6_rtmsg *rtmsg,
4449 struct fib6_config *cfg)
4450{
4451 *cfg = (struct fib6_config){
4452 .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
4453 : RT6_TABLE_MAIN,
4454 .fc_ifindex = rtmsg->rtmsg_ifindex,
4455 .fc_metric = rtmsg->rtmsg_metric,
4456 .fc_expires = rtmsg->rtmsg_info,
4457 .fc_dst_len = rtmsg->rtmsg_dst_len,
4458 .fc_src_len = rtmsg->rtmsg_src_len,
4459 .fc_flags = rtmsg->rtmsg_flags,
4460 .fc_type = rtmsg->rtmsg_type,
4461
4462 .fc_nlinfo.nl_net = net,
4463
4464 .fc_dst = rtmsg->rtmsg_dst,
4465 .fc_src = rtmsg->rtmsg_src,
4466 .fc_gateway = rtmsg->rtmsg_gateway,
4467 };
4468}
4469
4470int ipv6_route_ioctl(struct net *net, unsigned int cmd, struct in6_rtmsg *rtmsg)
4471{
4472 struct fib6_config cfg;
4473 int err;
4474
4475 if (cmd != SIOCADDRT && cmd != SIOCDELRT)
4476 return -EINVAL;
4477 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
4478 return -EPERM;
4479
4480 rtmsg_to_fib6_config(net, rtmsg, &cfg);
4481
4482 rtnl_lock();
4483 switch (cmd) {
4484 case SIOCADDRT:
4485 /* Only do the default setting of fc_metric in route adding */
4486 if (cfg.fc_metric == 0)
4487 cfg.fc_metric = IP6_RT_PRIO_USER;
4488 err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
4489 break;
4490 case SIOCDELRT:
4491 err = ip6_route_del(&cfg, NULL);
4492 break;
4493 }
4494 rtnl_unlock();
4495 return err;
4496}
4497
4498/*
4499 * Drop the packet on the floor
4500 */
4501
4502static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
4503{
4504 struct dst_entry *dst = skb_dst(skb);
4505 struct net *net = dev_net(dst->dev);
4506 struct inet6_dev *idev;
4507 SKB_DR(reason);
4508 int type;
4509
4510 if (netif_is_l3_master(skb->dev) ||
4511 dst->dev == net->loopback_dev)
4512 idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif));
4513 else
4514 idev = ip6_dst_idev(dst);
4515
4516 switch (ipstats_mib_noroutes) {
4517 case IPSTATS_MIB_INNOROUTES:
4518 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
4519 if (type == IPV6_ADDR_ANY) {
4520 SKB_DR_SET(reason, IP_INADDRERRORS);
4521 IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
4522 break;
4523 }
4524 SKB_DR_SET(reason, IP_INNOROUTES);
4525 fallthrough;
4526 case IPSTATS_MIB_OUTNOROUTES:
4527 SKB_DR_OR(reason, IP_OUTNOROUTES);
4528 IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
4529 break;
4530 }
4531
4532 /* Start over by dropping the dst for l3mdev case */
4533 if (netif_is_l3_master(skb->dev))
4534 skb_dst_drop(skb);
4535
4536 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
4537 kfree_skb_reason(skb, reason);
4538 return 0;
4539}
4540
4541static int ip6_pkt_discard(struct sk_buff *skb)
4542{
4543 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
4544}
4545
4546static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4547{
4548 skb->dev = skb_dst(skb)->dev;
4549 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
4550}
4551
4552static int ip6_pkt_prohibit(struct sk_buff *skb)
4553{
4554 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
4555}
4556
4557static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4558{
4559 skb->dev = skb_dst(skb)->dev;
4560 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
4561}
4562
4563/*
4564 * Allocate a dst for local (unicast / anycast) address.
4565 */
4566
4567struct fib6_info *addrconf_f6i_alloc(struct net *net,
4568 struct inet6_dev *idev,
4569 const struct in6_addr *addr,
4570 bool anycast, gfp_t gfp_flags,
4571 struct netlink_ext_ack *extack)
4572{
4573 struct fib6_config cfg = {
4574 .fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL,
4575 .fc_ifindex = idev->dev->ifindex,
4576 .fc_flags = RTF_UP | RTF_NONEXTHOP,
4577 .fc_dst = *addr,
4578 .fc_dst_len = 128,
4579 .fc_protocol = RTPROT_KERNEL,
4580 .fc_nlinfo.nl_net = net,
4581 .fc_ignore_dev_down = true,
4582 };
4583 struct fib6_info *f6i;
4584
4585 if (anycast) {
4586 cfg.fc_type = RTN_ANYCAST;
4587 cfg.fc_flags |= RTF_ANYCAST;
4588 } else {
4589 cfg.fc_type = RTN_LOCAL;
4590 cfg.fc_flags |= RTF_LOCAL;
4591 }
4592
4593 f6i = ip6_route_info_create(&cfg, gfp_flags, extack);
4594 if (!IS_ERR(f6i)) {
4595 f6i->dst_nocount = true;
4596
4597 if (!anycast &&
4598 (READ_ONCE(net->ipv6.devconf_all->disable_policy) ||
4599 READ_ONCE(idev->cnf.disable_policy)))
4600 f6i->dst_nopolicy = true;
4601 }
4602
4603 return f6i;
4604}
4605
4606/* remove deleted ip from prefsrc entries */
4607struct arg_dev_net_ip {
4608 struct net *net;
4609 struct in6_addr *addr;
4610};
4611
4612static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg)
4613{
4614 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
4615 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
4616
4617 if (!rt->nh &&
4618 rt != net->ipv6.fib6_null_entry &&
4619 ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr) &&
4620 !ipv6_chk_addr(net, addr, rt->fib6_nh->fib_nh_dev, 0)) {
4621 spin_lock_bh(&rt6_exception_lock);
4622 /* remove prefsrc entry */
4623 rt->fib6_prefsrc.plen = 0;
4624 spin_unlock_bh(&rt6_exception_lock);
4625 }
4626 return 0;
4627}
4628
4629void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
4630{
4631 struct net *net = dev_net(ifp->idev->dev);
4632 struct arg_dev_net_ip adni = {
4633 .net = net,
4634 .addr = &ifp->addr,
4635 };
4636 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
4637}
4638
4639#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT)
4640
4641/* Remove routers and update dst entries when gateway turn into host. */
4642static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
4643{
4644 struct in6_addr *gateway = (struct in6_addr *)arg;
4645 struct fib6_nh *nh;
4646
4647 /* RA routes do not use nexthops */
4648 if (rt->nh)
4649 return 0;
4650
4651 nh = rt->fib6_nh;
4652 if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
4653 nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6))
4654 return -1;
4655
4656 /* Further clean up cached routes in exception table.
4657 * This is needed because cached route may have a different
4658 * gateway than its 'parent' in the case of an ip redirect.
4659 */
4660 fib6_nh_exceptions_clean_tohost(nh, gateway);
4661
4662 return 0;
4663}
4664
4665void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
4666{
4667 fib6_clean_all(net, fib6_clean_tohost, gateway);
4668}
4669
4670struct arg_netdev_event {
4671 const struct net_device *dev;
4672 union {
4673 unsigned char nh_flags;
4674 unsigned long event;
4675 };
4676};
4677
4678static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
4679{
4680 struct fib6_info *iter;
4681 struct fib6_node *fn;
4682
4683 fn = rcu_dereference_protected(rt->fib6_node,
4684 lockdep_is_held(&rt->fib6_table->tb6_lock));
4685 iter = rcu_dereference_protected(fn->leaf,
4686 lockdep_is_held(&rt->fib6_table->tb6_lock));
4687 while (iter) {
4688 if (iter->fib6_metric == rt->fib6_metric &&
4689 rt6_qualify_for_ecmp(iter))
4690 return iter;
4691 iter = rcu_dereference_protected(iter->fib6_next,
4692 lockdep_is_held(&rt->fib6_table->tb6_lock));
4693 }
4694
4695 return NULL;
4696}
4697
4698/* only called for fib entries with builtin fib6_nh */
4699static bool rt6_is_dead(const struct fib6_info *rt)
4700{
4701 if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD ||
4702 (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN &&
4703 ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev)))
4704 return true;
4705
4706 return false;
4707}
4708
4709static int rt6_multipath_total_weight(const struct fib6_info *rt)
4710{
4711 struct fib6_info *iter;
4712 int total = 0;
4713
4714 if (!rt6_is_dead(rt))
4715 total += rt->fib6_nh->fib_nh_weight;
4716
4717 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
4718 if (!rt6_is_dead(iter))
4719 total += iter->fib6_nh->fib_nh_weight;
4720 }
4721
4722 return total;
4723}
4724
4725static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
4726{
4727 int upper_bound = -1;
4728
4729 if (!rt6_is_dead(rt)) {
4730 *weight += rt->fib6_nh->fib_nh_weight;
4731 upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
4732 total) - 1;
4733 }
4734 atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound);
4735}
4736
4737static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
4738{
4739 struct fib6_info *iter;
4740 int weight = 0;
4741
4742 rt6_upper_bound_set(rt, &weight, total);
4743
4744 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4745 rt6_upper_bound_set(iter, &weight, total);
4746}
4747
4748void rt6_multipath_rebalance(struct fib6_info *rt)
4749{
4750 struct fib6_info *first;
4751 int total;
4752
4753 /* In case the entire multipath route was marked for flushing,
4754 * then there is no need to rebalance upon the removal of every
4755 * sibling route.
4756 */
4757 if (!rt->fib6_nsiblings || rt->should_flush)
4758 return;
4759
4760 /* During lookup routes are evaluated in order, so we need to
4761 * make sure upper bounds are assigned from the first sibling
4762 * onwards.
4763 */
4764 first = rt6_multipath_first_sibling(rt);
4765 if (WARN_ON_ONCE(!first))
4766 return;
4767
4768 total = rt6_multipath_total_weight(first);
4769 rt6_multipath_upper_bound_set(first, total);
4770}
4771
4772static int fib6_ifup(struct fib6_info *rt, void *p_arg)
4773{
4774 const struct arg_netdev_event *arg = p_arg;
4775 struct net *net = dev_net(arg->dev);
4776
4777 if (rt != net->ipv6.fib6_null_entry && !rt->nh &&
4778 rt->fib6_nh->fib_nh_dev == arg->dev) {
4779 rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags;
4780 fib6_update_sernum_upto_root(net, rt);
4781 rt6_multipath_rebalance(rt);
4782 }
4783
4784 return 0;
4785}
4786
4787void rt6_sync_up(struct net_device *dev, unsigned char nh_flags)
4788{
4789 struct arg_netdev_event arg = {
4790 .dev = dev,
4791 {
4792 .nh_flags = nh_flags,
4793 },
4794 };
4795
4796 if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev))
4797 arg.nh_flags |= RTNH_F_LINKDOWN;
4798
4799 fib6_clean_all(dev_net(dev), fib6_ifup, &arg);
4800}
4801
4802/* only called for fib entries with inline fib6_nh */
4803static bool rt6_multipath_uses_dev(const struct fib6_info *rt,
4804 const struct net_device *dev)
4805{
4806 struct fib6_info *iter;
4807
4808 if (rt->fib6_nh->fib_nh_dev == dev)
4809 return true;
4810 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4811 if (iter->fib6_nh->fib_nh_dev == dev)
4812 return true;
4813
4814 return false;
4815}
4816
4817static void rt6_multipath_flush(struct fib6_info *rt)
4818{
4819 struct fib6_info *iter;
4820
4821 rt->should_flush = 1;
4822 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4823 iter->should_flush = 1;
4824}
4825
4826static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt,
4827 const struct net_device *down_dev)
4828{
4829 struct fib6_info *iter;
4830 unsigned int dead = 0;
4831
4832 if (rt->fib6_nh->fib_nh_dev == down_dev ||
4833 rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4834 dead++;
4835 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4836 if (iter->fib6_nh->fib_nh_dev == down_dev ||
4837 iter->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4838 dead++;
4839
4840 return dead;
4841}
4842
4843static void rt6_multipath_nh_flags_set(struct fib6_info *rt,
4844 const struct net_device *dev,
4845 unsigned char nh_flags)
4846{
4847 struct fib6_info *iter;
4848
4849 if (rt->fib6_nh->fib_nh_dev == dev)
4850 rt->fib6_nh->fib_nh_flags |= nh_flags;
4851 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4852 if (iter->fib6_nh->fib_nh_dev == dev)
4853 iter->fib6_nh->fib_nh_flags |= nh_flags;
4854}
4855
4856/* called with write lock held for table with rt */
4857static int fib6_ifdown(struct fib6_info *rt, void *p_arg)
4858{
4859 const struct arg_netdev_event *arg = p_arg;
4860 const struct net_device *dev = arg->dev;
4861 struct net *net = dev_net(dev);
4862
4863 if (rt == net->ipv6.fib6_null_entry || rt->nh)
4864 return 0;
4865
4866 switch (arg->event) {
4867 case NETDEV_UNREGISTER:
4868 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4869 case NETDEV_DOWN:
4870 if (rt->should_flush)
4871 return -1;
4872 if (!rt->fib6_nsiblings)
4873 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4874 if (rt6_multipath_uses_dev(rt, dev)) {
4875 unsigned int count;
4876
4877 count = rt6_multipath_dead_count(rt, dev);
4878 if (rt->fib6_nsiblings + 1 == count) {
4879 rt6_multipath_flush(rt);
4880 return -1;
4881 }
4882 rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
4883 RTNH_F_LINKDOWN);
4884 fib6_update_sernum(net, rt);
4885 rt6_multipath_rebalance(rt);
4886 }
4887 return -2;
4888 case NETDEV_CHANGE:
4889 if (rt->fib6_nh->fib_nh_dev != dev ||
4890 rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
4891 break;
4892 rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
4893 rt6_multipath_rebalance(rt);
4894 break;
4895 }
4896
4897 return 0;
4898}
4899
4900void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
4901{
4902 struct arg_netdev_event arg = {
4903 .dev = dev,
4904 {
4905 .event = event,
4906 },
4907 };
4908 struct net *net = dev_net(dev);
4909
4910 if (net->ipv6.sysctl.skip_notify_on_dev_down)
4911 fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
4912 else
4913 fib6_clean_all(net, fib6_ifdown, &arg);
4914}
4915
4916void rt6_disable_ip(struct net_device *dev, unsigned long event)
4917{
4918 rt6_sync_down_dev(dev, event);
4919 rt6_uncached_list_flush_dev(dev);
4920 neigh_ifdown(&nd_tbl, dev);
4921}
4922
4923struct rt6_mtu_change_arg {
4924 struct net_device *dev;
4925 unsigned int mtu;
4926 struct fib6_info *f6i;
4927};
4928
4929static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg)
4930{
4931 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *)_arg;
4932 struct fib6_info *f6i = arg->f6i;
4933
4934 /* For administrative MTU increase, there is no way to discover
4935 * IPv6 PMTU increase, so PMTU increase should be updated here.
4936 * Since RFC 1981 doesn't include administrative MTU increase
4937 * update PMTU increase is a MUST. (i.e. jumbo frame)
4938 */
4939 if (nh->fib_nh_dev == arg->dev) {
4940 struct inet6_dev *idev = __in6_dev_get(arg->dev);
4941 u32 mtu = f6i->fib6_pmtu;
4942
4943 if (mtu >= arg->mtu ||
4944 (mtu < arg->mtu && mtu == idev->cnf.mtu6))
4945 fib6_metric_set(f6i, RTAX_MTU, arg->mtu);
4946
4947 spin_lock_bh(&rt6_exception_lock);
4948 rt6_exceptions_update_pmtu(idev, nh, arg->mtu);
4949 spin_unlock_bh(&rt6_exception_lock);
4950 }
4951
4952 return 0;
4953}
4954
4955static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
4956{
4957 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
4958 struct inet6_dev *idev;
4959
4960 /* In IPv6 pmtu discovery is not optional,
4961 so that RTAX_MTU lock cannot disable it.
4962 We still use this lock to block changes
4963 caused by addrconf/ndisc.
4964 */
4965
4966 idev = __in6_dev_get(arg->dev);
4967 if (!idev)
4968 return 0;
4969
4970 if (fib6_metric_locked(f6i, RTAX_MTU))
4971 return 0;
4972
4973 arg->f6i = f6i;
4974 if (f6i->nh) {
4975 /* fib6_nh_mtu_change only returns 0, so this is safe */
4976 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change,
4977 arg);
4978 }
4979
4980 return fib6_nh_mtu_change(f6i->fib6_nh, arg);
4981}
4982
4983void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
4984{
4985 struct rt6_mtu_change_arg arg = {
4986 .dev = dev,
4987 .mtu = mtu,
4988 };
4989
4990 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
4991}
4992
4993static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
4994 [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 },
4995 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
4996 [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
4997 [RTA_OIF] = { .type = NLA_U32 },
4998 [RTA_IIF] = { .type = NLA_U32 },
4999 [RTA_PRIORITY] = { .type = NLA_U32 },
5000 [RTA_METRICS] = { .type = NLA_NESTED },
5001 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
5002 [RTA_PREF] = { .type = NLA_U8 },
5003 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
5004 [RTA_ENCAP] = { .type = NLA_NESTED },
5005 [RTA_EXPIRES] = { .type = NLA_U32 },
5006 [RTA_UID] = { .type = NLA_U32 },
5007 [RTA_MARK] = { .type = NLA_U32 },
5008 [RTA_TABLE] = { .type = NLA_U32 },
5009 [RTA_IP_PROTO] = { .type = NLA_U8 },
5010 [RTA_SPORT] = { .type = NLA_U16 },
5011 [RTA_DPORT] = { .type = NLA_U16 },
5012 [RTA_NH_ID] = { .type = NLA_U32 },
5013};
5014
5015static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
5016 struct fib6_config *cfg,
5017 struct netlink_ext_ack *extack)
5018{
5019 struct rtmsg *rtm;
5020 struct nlattr *tb[RTA_MAX+1];
5021 unsigned int pref;
5022 int err;
5023
5024 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
5025 rtm_ipv6_policy, extack);
5026 if (err < 0)
5027 goto errout;
5028
5029 err = -EINVAL;
5030 rtm = nlmsg_data(nlh);
5031
5032 if (rtm->rtm_tos) {
5033 NL_SET_ERR_MSG(extack,
5034 "Invalid dsfield (tos): option not available for IPv6");
5035 goto errout;
5036 }
5037
5038 *cfg = (struct fib6_config){
5039 .fc_table = rtm->rtm_table,
5040 .fc_dst_len = rtm->rtm_dst_len,
5041 .fc_src_len = rtm->rtm_src_len,
5042 .fc_flags = RTF_UP,
5043 .fc_protocol = rtm->rtm_protocol,
5044 .fc_type = rtm->rtm_type,
5045
5046 .fc_nlinfo.portid = NETLINK_CB(skb).portid,
5047 .fc_nlinfo.nlh = nlh,
5048 .fc_nlinfo.nl_net = sock_net(skb->sk),
5049 };
5050
5051 if (rtm->rtm_type == RTN_UNREACHABLE ||
5052 rtm->rtm_type == RTN_BLACKHOLE ||
5053 rtm->rtm_type == RTN_PROHIBIT ||
5054 rtm->rtm_type == RTN_THROW)
5055 cfg->fc_flags |= RTF_REJECT;
5056
5057 if (rtm->rtm_type == RTN_LOCAL)
5058 cfg->fc_flags |= RTF_LOCAL;
5059
5060 if (rtm->rtm_flags & RTM_F_CLONED)
5061 cfg->fc_flags |= RTF_CACHE;
5062
5063 cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
5064
5065 if (tb[RTA_NH_ID]) {
5066 if (tb[RTA_GATEWAY] || tb[RTA_OIF] ||
5067 tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) {
5068 NL_SET_ERR_MSG(extack,
5069 "Nexthop specification and nexthop id are mutually exclusive");
5070 goto errout;
5071 }
5072 cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]);
5073 }
5074
5075 if (tb[RTA_GATEWAY]) {
5076 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
5077 cfg->fc_flags |= RTF_GATEWAY;
5078 }
5079 if (tb[RTA_VIA]) {
5080 NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute");
5081 goto errout;
5082 }
5083
5084 if (tb[RTA_DST]) {
5085 int plen = (rtm->rtm_dst_len + 7) >> 3;
5086
5087 if (nla_len(tb[RTA_DST]) < plen)
5088 goto errout;
5089
5090 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
5091 }
5092
5093 if (tb[RTA_SRC]) {
5094 int plen = (rtm->rtm_src_len + 7) >> 3;
5095
5096 if (nla_len(tb[RTA_SRC]) < plen)
5097 goto errout;
5098
5099 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
5100 }
5101
5102 if (tb[RTA_PREFSRC])
5103 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
5104
5105 if (tb[RTA_OIF])
5106 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
5107
5108 if (tb[RTA_PRIORITY])
5109 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
5110
5111 if (tb[RTA_METRICS]) {
5112 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
5113 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
5114 }
5115
5116 if (tb[RTA_TABLE])
5117 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
5118
5119 if (tb[RTA_MULTIPATH]) {
5120 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
5121 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
5122
5123 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
5124 cfg->fc_mp_len, extack);
5125 if (err < 0)
5126 goto errout;
5127 }
5128
5129 if (tb[RTA_PREF]) {
5130 pref = nla_get_u8(tb[RTA_PREF]);
5131 if (pref != ICMPV6_ROUTER_PREF_LOW &&
5132 pref != ICMPV6_ROUTER_PREF_HIGH)
5133 pref = ICMPV6_ROUTER_PREF_MEDIUM;
5134 cfg->fc_flags |= RTF_PREF(pref);
5135 }
5136
5137 if (tb[RTA_ENCAP])
5138 cfg->fc_encap = tb[RTA_ENCAP];
5139
5140 if (tb[RTA_ENCAP_TYPE]) {
5141 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
5142
5143 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
5144 if (err < 0)
5145 goto errout;
5146 }
5147
5148 if (tb[RTA_EXPIRES]) {
5149 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
5150
5151 if (addrconf_finite_timeout(timeout)) {
5152 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
5153 cfg->fc_flags |= RTF_EXPIRES;
5154 }
5155 }
5156
5157 err = 0;
5158errout:
5159 return err;
5160}
5161
5162struct rt6_nh {
5163 struct fib6_info *fib6_info;
5164 struct fib6_config r_cfg;
5165 struct list_head next;
5166};
5167
5168static int ip6_route_info_append(struct net *net,
5169 struct list_head *rt6_nh_list,
5170 struct fib6_info *rt,
5171 struct fib6_config *r_cfg)
5172{
5173 struct rt6_nh *nh;
5174 int err = -EEXIST;
5175
5176 list_for_each_entry(nh, rt6_nh_list, next) {
5177 /* check if fib6_info already exists */
5178 if (rt6_duplicate_nexthop(nh->fib6_info, rt))
5179 return err;
5180 }
5181
5182 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
5183 if (!nh)
5184 return -ENOMEM;
5185 nh->fib6_info = rt;
5186 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
5187 list_add_tail(&nh->next, rt6_nh_list);
5188
5189 return 0;
5190}
5191
5192static void ip6_route_mpath_notify(struct fib6_info *rt,
5193 struct fib6_info *rt_last,
5194 struct nl_info *info,
5195 __u16 nlflags)
5196{
5197 /* if this is an APPEND route, then rt points to the first route
5198 * inserted and rt_last points to last route inserted. Userspace
5199 * wants a consistent dump of the route which starts at the first
5200 * nexthop. Since sibling routes are always added at the end of
5201 * the list, find the first sibling of the last route appended
5202 */
5203 rcu_read_lock();
5204
5205 if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
5206 rt = list_first_or_null_rcu(&rt_last->fib6_siblings,
5207 struct fib6_info,
5208 fib6_siblings);
5209 }
5210
5211 if (rt)
5212 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
5213
5214 rcu_read_unlock();
5215}
5216
5217static bool ip6_route_mpath_should_notify(const struct fib6_info *rt)
5218{
5219 bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
5220 bool should_notify = false;
5221 struct fib6_info *leaf;
5222 struct fib6_node *fn;
5223
5224 rcu_read_lock();
5225 fn = rcu_dereference(rt->fib6_node);
5226 if (!fn)
5227 goto out;
5228
5229 leaf = rcu_dereference(fn->leaf);
5230 if (!leaf)
5231 goto out;
5232
5233 if (rt == leaf ||
5234 (rt_can_ecmp && rt->fib6_metric == leaf->fib6_metric &&
5235 rt6_qualify_for_ecmp(leaf)))
5236 should_notify = true;
5237out:
5238 rcu_read_unlock();
5239
5240 return should_notify;
5241}
5242
5243static int fib6_gw_from_attr(struct in6_addr *gw, struct nlattr *nla,
5244 struct netlink_ext_ack *extack)
5245{
5246 if (nla_len(nla) < sizeof(*gw)) {
5247 NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_GATEWAY");
5248 return -EINVAL;
5249 }
5250
5251 *gw = nla_get_in6_addr(nla);
5252
5253 return 0;
5254}
5255
5256static int ip6_route_multipath_add(struct fib6_config *cfg,
5257 struct netlink_ext_ack *extack)
5258{
5259 struct fib6_info *rt_notif = NULL, *rt_last = NULL;
5260 struct nl_info *info = &cfg->fc_nlinfo;
5261 struct fib6_config r_cfg;
5262 struct rtnexthop *rtnh;
5263 struct fib6_info *rt;
5264 struct rt6_nh *err_nh;
5265 struct rt6_nh *nh, *nh_safe;
5266 __u16 nlflags;
5267 int remaining;
5268 int attrlen;
5269 int err = 1;
5270 int nhn = 0;
5271 int replace = (cfg->fc_nlinfo.nlh &&
5272 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
5273 LIST_HEAD(rt6_nh_list);
5274
5275 nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
5276 if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
5277 nlflags |= NLM_F_APPEND;
5278
5279 remaining = cfg->fc_mp_len;
5280 rtnh = (struct rtnexthop *)cfg->fc_mp;
5281
5282 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
5283 * fib6_info structs per nexthop
5284 */
5285 while (rtnh_ok(rtnh, remaining)) {
5286 memcpy(&r_cfg, cfg, sizeof(*cfg));
5287 if (rtnh->rtnh_ifindex)
5288 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5289
5290 attrlen = rtnh_attrlen(rtnh);
5291 if (attrlen > 0) {
5292 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5293
5294 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5295 if (nla) {
5296 err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
5297 extack);
5298 if (err)
5299 goto cleanup;
5300
5301 r_cfg.fc_flags |= RTF_GATEWAY;
5302 }
5303 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
5304
5305 /* RTA_ENCAP_TYPE length checked in
5306 * lwtunnel_valid_encap_type_attr
5307 */
5308 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
5309 if (nla)
5310 r_cfg.fc_encap_type = nla_get_u16(nla);
5311 }
5312
5313 r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
5314 rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
5315 if (IS_ERR(rt)) {
5316 err = PTR_ERR(rt);
5317 rt = NULL;
5318 goto cleanup;
5319 }
5320 if (!rt6_qualify_for_ecmp(rt)) {
5321 err = -EINVAL;
5322 NL_SET_ERR_MSG(extack,
5323 "Device only routes can not be added for IPv6 using the multipath API.");
5324 fib6_info_release(rt);
5325 goto cleanup;
5326 }
5327
5328 rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1;
5329
5330 err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
5331 rt, &r_cfg);
5332 if (err) {
5333 fib6_info_release(rt);
5334 goto cleanup;
5335 }
5336
5337 rtnh = rtnh_next(rtnh, &remaining);
5338 }
5339
5340 if (list_empty(&rt6_nh_list)) {
5341 NL_SET_ERR_MSG(extack,
5342 "Invalid nexthop configuration - no valid nexthops");
5343 return -EINVAL;
5344 }
5345
5346 /* for add and replace send one notification with all nexthops.
5347 * Skip the notification in fib6_add_rt2node and send one with
5348 * the full route when done
5349 */
5350 info->skip_notify = 1;
5351
5352 /* For add and replace, send one notification with all nexthops. For
5353 * append, send one notification with all appended nexthops.
5354 */
5355 info->skip_notify_kernel = 1;
5356
5357 err_nh = NULL;
5358 list_for_each_entry(nh, &rt6_nh_list, next) {
5359 err = __ip6_ins_rt(nh->fib6_info, info, extack);
5360
5361 if (err) {
5362 if (replace && nhn)
5363 NL_SET_ERR_MSG_MOD(extack,
5364 "multipath route replace failed (check consistency of installed routes)");
5365 err_nh = nh;
5366 goto add_errout;
5367 }
5368 /* save reference to last route successfully inserted */
5369 rt_last = nh->fib6_info;
5370
5371 /* save reference to first route for notification */
5372 if (!rt_notif)
5373 rt_notif = nh->fib6_info;
5374
5375 /* Because each route is added like a single route we remove
5376 * these flags after the first nexthop: if there is a collision,
5377 * we have already failed to add the first nexthop:
5378 * fib6_add_rt2node() has rejected it; when replacing, old
5379 * nexthops have been replaced by first new, the rest should
5380 * be added to it.
5381 */
5382 if (cfg->fc_nlinfo.nlh) {
5383 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
5384 NLM_F_REPLACE);
5385 cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
5386 }
5387 nhn++;
5388 }
5389
5390 /* An in-kernel notification should only be sent in case the new
5391 * multipath route is added as the first route in the node, or if
5392 * it was appended to it. We pass 'rt_notif' since it is the first
5393 * sibling and might allow us to skip some checks in the replace case.
5394 */
5395 if (ip6_route_mpath_should_notify(rt_notif)) {
5396 enum fib_event_type fib_event;
5397
5398 if (rt_notif->fib6_nsiblings != nhn - 1)
5399 fib_event = FIB_EVENT_ENTRY_APPEND;
5400 else
5401 fib_event = FIB_EVENT_ENTRY_REPLACE;
5402
5403 err = call_fib6_multipath_entry_notifiers(info->nl_net,
5404 fib_event, rt_notif,
5405 nhn - 1, extack);
5406 if (err) {
5407 /* Delete all the siblings that were just added */
5408 err_nh = NULL;
5409 goto add_errout;
5410 }
5411 }
5412
5413 /* success ... tell user about new route */
5414 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5415 goto cleanup;
5416
5417add_errout:
5418 /* send notification for routes that were added so that
5419 * the delete notifications sent by ip6_route_del are
5420 * coherent
5421 */
5422 if (rt_notif)
5423 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5424
5425 /* Delete routes that were already added */
5426 list_for_each_entry(nh, &rt6_nh_list, next) {
5427 if (err_nh == nh)
5428 break;
5429 ip6_route_del(&nh->r_cfg, extack);
5430 }
5431
5432cleanup:
5433 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
5434 fib6_info_release(nh->fib6_info);
5435 list_del(&nh->next);
5436 kfree(nh);
5437 }
5438
5439 return err;
5440}
5441
5442static int ip6_route_multipath_del(struct fib6_config *cfg,
5443 struct netlink_ext_ack *extack)
5444{
5445 struct fib6_config r_cfg;
5446 struct rtnexthop *rtnh;
5447 int last_err = 0;
5448 int remaining;
5449 int attrlen;
5450 int err;
5451
5452 remaining = cfg->fc_mp_len;
5453 rtnh = (struct rtnexthop *)cfg->fc_mp;
5454
5455 /* Parse a Multipath Entry */
5456 while (rtnh_ok(rtnh, remaining)) {
5457 memcpy(&r_cfg, cfg, sizeof(*cfg));
5458 if (rtnh->rtnh_ifindex)
5459 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5460
5461 attrlen = rtnh_attrlen(rtnh);
5462 if (attrlen > 0) {
5463 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5464
5465 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5466 if (nla) {
5467 err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
5468 extack);
5469 if (err) {
5470 last_err = err;
5471 goto next_rtnh;
5472 }
5473
5474 r_cfg.fc_flags |= RTF_GATEWAY;
5475 }
5476 }
5477 err = ip6_route_del(&r_cfg, extack);
5478 if (err)
5479 last_err = err;
5480
5481next_rtnh:
5482 rtnh = rtnh_next(rtnh, &remaining);
5483 }
5484
5485 return last_err;
5486}
5487
5488static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5489 struct netlink_ext_ack *extack)
5490{
5491 struct fib6_config cfg;
5492 int err;
5493
5494 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5495 if (err < 0)
5496 return err;
5497
5498 if (cfg.fc_nh_id &&
5499 !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id)) {
5500 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
5501 return -EINVAL;
5502 }
5503
5504 if (cfg.fc_mp)
5505 return ip6_route_multipath_del(&cfg, extack);
5506 else {
5507 cfg.fc_delete_all_nh = 1;
5508 return ip6_route_del(&cfg, extack);
5509 }
5510}
5511
5512static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5513 struct netlink_ext_ack *extack)
5514{
5515 struct fib6_config cfg;
5516 int err;
5517
5518 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5519 if (err < 0)
5520 return err;
5521
5522 if (cfg.fc_metric == 0)
5523 cfg.fc_metric = IP6_RT_PRIO_USER;
5524
5525 if (cfg.fc_mp)
5526 return ip6_route_multipath_add(&cfg, extack);
5527 else
5528 return ip6_route_add(&cfg, GFP_KERNEL, extack);
5529}
5530
5531/* add the overhead of this fib6_nh to nexthop_len */
5532static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
5533{
5534 int *nexthop_len = arg;
5535
5536 *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */
5537 + NLA_ALIGN(sizeof(struct rtnexthop))
5538 + nla_total_size(16); /* RTA_GATEWAY */
5539
5540 if (nh->fib_nh_lws) {
5541 /* RTA_ENCAP_TYPE */
5542 *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5543 /* RTA_ENCAP */
5544 *nexthop_len += nla_total_size(2);
5545 }
5546
5547 return 0;
5548}
5549
5550static size_t rt6_nlmsg_size(struct fib6_info *f6i)
5551{
5552 int nexthop_len;
5553
5554 if (f6i->nh) {
5555 nexthop_len = nla_total_size(4); /* RTA_NH_ID */
5556 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size,
5557 &nexthop_len);
5558 } else {
5559 struct fib6_nh *nh = f6i->fib6_nh;
5560 struct fib6_info *sibling;
5561
5562 nexthop_len = 0;
5563 if (f6i->fib6_nsiblings) {
5564 rt6_nh_nlmsg_size(nh, &nexthop_len);
5565
5566 rcu_read_lock();
5567
5568 list_for_each_entry_rcu(sibling, &f6i->fib6_siblings,
5569 fib6_siblings) {
5570 rt6_nh_nlmsg_size(sibling->fib6_nh, &nexthop_len);
5571 }
5572
5573 rcu_read_unlock();
5574 }
5575 nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5576 }
5577
5578 return NLMSG_ALIGN(sizeof(struct rtmsg))
5579 + nla_total_size(16) /* RTA_SRC */
5580 + nla_total_size(16) /* RTA_DST */
5581 + nla_total_size(16) /* RTA_GATEWAY */
5582 + nla_total_size(16) /* RTA_PREFSRC */
5583 + nla_total_size(4) /* RTA_TABLE */
5584 + nla_total_size(4) /* RTA_IIF */
5585 + nla_total_size(4) /* RTA_OIF */
5586 + nla_total_size(4) /* RTA_PRIORITY */
5587 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
5588 + nla_total_size(sizeof(struct rta_cacheinfo))
5589 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
5590 + nla_total_size(1) /* RTA_PREF */
5591 + nexthop_len;
5592}
5593
5594static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh,
5595 unsigned char *flags)
5596{
5597 if (nexthop_is_multipath(nh)) {
5598 struct nlattr *mp;
5599
5600 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5601 if (!mp)
5602 goto nla_put_failure;
5603
5604 if (nexthop_mpath_fill_node(skb, nh, AF_INET6))
5605 goto nla_put_failure;
5606
5607 nla_nest_end(skb, mp);
5608 } else {
5609 struct fib6_nh *fib6_nh;
5610
5611 fib6_nh = nexthop_fib6_nh(nh);
5612 if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6,
5613 flags, false) < 0)
5614 goto nla_put_failure;
5615 }
5616
5617 return 0;
5618
5619nla_put_failure:
5620 return -EMSGSIZE;
5621}
5622
5623static int rt6_fill_node(struct net *net, struct sk_buff *skb,
5624 struct fib6_info *rt, struct dst_entry *dst,
5625 struct in6_addr *dest, struct in6_addr *src,
5626 int iif, int type, u32 portid, u32 seq,
5627 unsigned int flags)
5628{
5629 struct rt6_info *rt6 = dst_rt6_info(dst);
5630 struct rt6key *rt6_dst, *rt6_src;
5631 u32 *pmetrics, table, rt6_flags;
5632 unsigned char nh_flags = 0;
5633 struct nlmsghdr *nlh;
5634 struct rtmsg *rtm;
5635 long expires = 0;
5636
5637 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
5638 if (!nlh)
5639 return -EMSGSIZE;
5640
5641 if (rt6) {
5642 rt6_dst = &rt6->rt6i_dst;
5643 rt6_src = &rt6->rt6i_src;
5644 rt6_flags = rt6->rt6i_flags;
5645 } else {
5646 rt6_dst = &rt->fib6_dst;
5647 rt6_src = &rt->fib6_src;
5648 rt6_flags = rt->fib6_flags;
5649 }
5650
5651 rtm = nlmsg_data(nlh);
5652 rtm->rtm_family = AF_INET6;
5653 rtm->rtm_dst_len = rt6_dst->plen;
5654 rtm->rtm_src_len = rt6_src->plen;
5655 rtm->rtm_tos = 0;
5656 if (rt->fib6_table)
5657 table = rt->fib6_table->tb6_id;
5658 else
5659 table = RT6_TABLE_UNSPEC;
5660 rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
5661 if (nla_put_u32(skb, RTA_TABLE, table))
5662 goto nla_put_failure;
5663
5664 rtm->rtm_type = rt->fib6_type;
5665 rtm->rtm_flags = 0;
5666 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
5667 rtm->rtm_protocol = rt->fib6_protocol;
5668
5669 if (rt6_flags & RTF_CACHE)
5670 rtm->rtm_flags |= RTM_F_CLONED;
5671
5672 if (dest) {
5673 if (nla_put_in6_addr(skb, RTA_DST, dest))
5674 goto nla_put_failure;
5675 rtm->rtm_dst_len = 128;
5676 } else if (rtm->rtm_dst_len)
5677 if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr))
5678 goto nla_put_failure;
5679#ifdef CONFIG_IPV6_SUBTREES
5680 if (src) {
5681 if (nla_put_in6_addr(skb, RTA_SRC, src))
5682 goto nla_put_failure;
5683 rtm->rtm_src_len = 128;
5684 } else if (rtm->rtm_src_len &&
5685 nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
5686 goto nla_put_failure;
5687#endif
5688 if (iif) {
5689#ifdef CONFIG_IPV6_MROUTE
5690 if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
5691 int err = ip6mr_get_route(net, skb, rtm, portid);
5692
5693 if (err == 0)
5694 return 0;
5695 if (err < 0)
5696 goto nla_put_failure;
5697 } else
5698#endif
5699 if (nla_put_u32(skb, RTA_IIF, iif))
5700 goto nla_put_failure;
5701 } else if (dest) {
5702 struct in6_addr saddr_buf;
5703 if (ip6_route_get_saddr(net, rt, dest, 0, 0, &saddr_buf) == 0 &&
5704 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5705 goto nla_put_failure;
5706 }
5707
5708 if (rt->fib6_prefsrc.plen) {
5709 struct in6_addr saddr_buf;
5710 saddr_buf = rt->fib6_prefsrc.addr;
5711 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5712 goto nla_put_failure;
5713 }
5714
5715 pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics;
5716 if (rtnetlink_put_metrics(skb, pmetrics) < 0)
5717 goto nla_put_failure;
5718
5719 if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric))
5720 goto nla_put_failure;
5721
5722 /* For multipath routes, walk the siblings list and add
5723 * each as a nexthop within RTA_MULTIPATH.
5724 */
5725 if (rt6) {
5726 if (rt6_flags & RTF_GATEWAY &&
5727 nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
5728 goto nla_put_failure;
5729
5730 if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
5731 goto nla_put_failure;
5732
5733 if (dst->lwtstate &&
5734 lwtunnel_fill_encap(skb, dst->lwtstate, RTA_ENCAP, RTA_ENCAP_TYPE) < 0)
5735 goto nla_put_failure;
5736 } else if (rt->fib6_nsiblings) {
5737 struct fib6_info *sibling;
5738 struct nlattr *mp;
5739
5740 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5741 if (!mp)
5742 goto nla_put_failure;
5743
5744 if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common,
5745 rt->fib6_nh->fib_nh_weight, AF_INET6,
5746 0) < 0)
5747 goto nla_put_failure;
5748
5749 rcu_read_lock();
5750
5751 list_for_each_entry_rcu(sibling, &rt->fib6_siblings,
5752 fib6_siblings) {
5753 if (fib_add_nexthop(skb, &sibling->fib6_nh->nh_common,
5754 sibling->fib6_nh->fib_nh_weight,
5755 AF_INET6, 0) < 0) {
5756 rcu_read_unlock();
5757
5758 goto nla_put_failure;
5759 }
5760 }
5761
5762 rcu_read_unlock();
5763
5764 nla_nest_end(skb, mp);
5765 } else if (rt->nh) {
5766 if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id))
5767 goto nla_put_failure;
5768
5769 if (nexthop_is_blackhole(rt->nh))
5770 rtm->rtm_type = RTN_BLACKHOLE;
5771
5772 if (READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode) &&
5773 rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0)
5774 goto nla_put_failure;
5775
5776 rtm->rtm_flags |= nh_flags;
5777 } else {
5778 if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6,
5779 &nh_flags, false) < 0)
5780 goto nla_put_failure;
5781
5782 rtm->rtm_flags |= nh_flags;
5783 }
5784
5785 if (rt6_flags & RTF_EXPIRES) {
5786 expires = dst ? dst->expires : rt->expires;
5787 expires -= jiffies;
5788 }
5789
5790 if (!dst) {
5791 if (READ_ONCE(rt->offload))
5792 rtm->rtm_flags |= RTM_F_OFFLOAD;
5793 if (READ_ONCE(rt->trap))
5794 rtm->rtm_flags |= RTM_F_TRAP;
5795 if (READ_ONCE(rt->offload_failed))
5796 rtm->rtm_flags |= RTM_F_OFFLOAD_FAILED;
5797 }
5798
5799 if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
5800 goto nla_put_failure;
5801
5802 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
5803 goto nla_put_failure;
5804
5805
5806 nlmsg_end(skb, nlh);
5807 return 0;
5808
5809nla_put_failure:
5810 nlmsg_cancel(skb, nlh);
5811 return -EMSGSIZE;
5812}
5813
5814static int fib6_info_nh_uses_dev(struct fib6_nh *nh, void *arg)
5815{
5816 const struct net_device *dev = arg;
5817
5818 if (nh->fib_nh_dev == dev)
5819 return 1;
5820
5821 return 0;
5822}
5823
5824static bool fib6_info_uses_dev(const struct fib6_info *f6i,
5825 const struct net_device *dev)
5826{
5827 if (f6i->nh) {
5828 struct net_device *_dev = (struct net_device *)dev;
5829
5830 return !!nexthop_for_each_fib6_nh(f6i->nh,
5831 fib6_info_nh_uses_dev,
5832 _dev);
5833 }
5834
5835 if (f6i->fib6_nh->fib_nh_dev == dev)
5836 return true;
5837
5838 if (f6i->fib6_nsiblings) {
5839 struct fib6_info *sibling, *next_sibling;
5840
5841 list_for_each_entry_safe(sibling, next_sibling,
5842 &f6i->fib6_siblings, fib6_siblings) {
5843 if (sibling->fib6_nh->fib_nh_dev == dev)
5844 return true;
5845 }
5846 }
5847
5848 return false;
5849}
5850
5851struct fib6_nh_exception_dump_walker {
5852 struct rt6_rtnl_dump_arg *dump;
5853 struct fib6_info *rt;
5854 unsigned int flags;
5855 unsigned int skip;
5856 unsigned int count;
5857};
5858
5859static int rt6_nh_dump_exceptions(struct fib6_nh *nh, void *arg)
5860{
5861 struct fib6_nh_exception_dump_walker *w = arg;
5862 struct rt6_rtnl_dump_arg *dump = w->dump;
5863 struct rt6_exception_bucket *bucket;
5864 struct rt6_exception *rt6_ex;
5865 int i, err;
5866
5867 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
5868 if (!bucket)
5869 return 0;
5870
5871 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
5872 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
5873 if (w->skip) {
5874 w->skip--;
5875 continue;
5876 }
5877
5878 /* Expiration of entries doesn't bump sernum, insertion
5879 * does. Removal is triggered by insertion, so we can
5880 * rely on the fact that if entries change between two
5881 * partial dumps, this node is scanned again completely,
5882 * see rt6_insert_exception() and fib6_dump_table().
5883 *
5884 * Count expired entries we go through as handled
5885 * entries that we'll skip next time, in case of partial
5886 * node dump. Otherwise, if entries expire meanwhile,
5887 * we'll skip the wrong amount.
5888 */
5889 if (rt6_check_expired(rt6_ex->rt6i)) {
5890 w->count++;
5891 continue;
5892 }
5893
5894 err = rt6_fill_node(dump->net, dump->skb, w->rt,
5895 &rt6_ex->rt6i->dst, NULL, NULL, 0,
5896 RTM_NEWROUTE,
5897 NETLINK_CB(dump->cb->skb).portid,
5898 dump->cb->nlh->nlmsg_seq, w->flags);
5899 if (err)
5900 return err;
5901
5902 w->count++;
5903 }
5904 bucket++;
5905 }
5906
5907 return 0;
5908}
5909
5910/* Return -1 if done with node, number of handled routes on partial dump */
5911int rt6_dump_route(struct fib6_info *rt, void *p_arg, unsigned int skip)
5912{
5913 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
5914 struct fib_dump_filter *filter = &arg->filter;
5915 unsigned int flags = NLM_F_MULTI;
5916 struct net *net = arg->net;
5917 int count = 0;
5918
5919 if (rt == net->ipv6.fib6_null_entry)
5920 return -1;
5921
5922 if ((filter->flags & RTM_F_PREFIX) &&
5923 !(rt->fib6_flags & RTF_PREFIX_RT)) {
5924 /* success since this is not a prefix route */
5925 return -1;
5926 }
5927 if (filter->filter_set &&
5928 ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
5929 (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
5930 (filter->protocol && rt->fib6_protocol != filter->protocol))) {
5931 return -1;
5932 }
5933
5934 if (filter->filter_set ||
5935 !filter->dump_routes || !filter->dump_exceptions) {
5936 flags |= NLM_F_DUMP_FILTERED;
5937 }
5938
5939 if (filter->dump_routes) {
5940 if (skip) {
5941 skip--;
5942 } else {
5943 if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL,
5944 0, RTM_NEWROUTE,
5945 NETLINK_CB(arg->cb->skb).portid,
5946 arg->cb->nlh->nlmsg_seq, flags)) {
5947 return 0;
5948 }
5949 count++;
5950 }
5951 }
5952
5953 if (filter->dump_exceptions) {
5954 struct fib6_nh_exception_dump_walker w = { .dump = arg,
5955 .rt = rt,
5956 .flags = flags,
5957 .skip = skip,
5958 .count = 0 };
5959 int err;
5960
5961 rcu_read_lock();
5962 if (rt->nh) {
5963 err = nexthop_for_each_fib6_nh(rt->nh,
5964 rt6_nh_dump_exceptions,
5965 &w);
5966 } else {
5967 err = rt6_nh_dump_exceptions(rt->fib6_nh, &w);
5968 }
5969 rcu_read_unlock();
5970
5971 if (err)
5972 return count + w.count;
5973 }
5974
5975 return -1;
5976}
5977
5978static int inet6_rtm_valid_getroute_req(struct sk_buff *skb,
5979 const struct nlmsghdr *nlh,
5980 struct nlattr **tb,
5981 struct netlink_ext_ack *extack)
5982{
5983 struct rtmsg *rtm;
5984 int i, err;
5985
5986 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
5987 NL_SET_ERR_MSG_MOD(extack,
5988 "Invalid header for get route request");
5989 return -EINVAL;
5990 }
5991
5992 if (!netlink_strict_get_check(skb))
5993 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
5994 rtm_ipv6_policy, extack);
5995
5996 rtm = nlmsg_data(nlh);
5997 if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
5998 (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
5999 rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope ||
6000 rtm->rtm_type) {
6001 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
6002 return -EINVAL;
6003 }
6004 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
6005 NL_SET_ERR_MSG_MOD(extack,
6006 "Invalid flags for get route request");
6007 return -EINVAL;
6008 }
6009
6010 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
6011 rtm_ipv6_policy, extack);
6012 if (err)
6013 return err;
6014
6015 if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
6016 (tb[RTA_DST] && !rtm->rtm_dst_len)) {
6017 NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6");
6018 return -EINVAL;
6019 }
6020
6021 for (i = 0; i <= RTA_MAX; i++) {
6022 if (!tb[i])
6023 continue;
6024
6025 switch (i) {
6026 case RTA_SRC:
6027 case RTA_DST:
6028 case RTA_IIF:
6029 case RTA_OIF:
6030 case RTA_MARK:
6031 case RTA_UID:
6032 case RTA_SPORT:
6033 case RTA_DPORT:
6034 case RTA_IP_PROTO:
6035 break;
6036 default:
6037 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
6038 return -EINVAL;
6039 }
6040 }
6041
6042 return 0;
6043}
6044
6045static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
6046 struct netlink_ext_ack *extack)
6047{
6048 struct net *net = sock_net(in_skb->sk);
6049 struct nlattr *tb[RTA_MAX+1];
6050 int err, iif = 0, oif = 0;
6051 struct fib6_info *from;
6052 struct dst_entry *dst;
6053 struct rt6_info *rt;
6054 struct sk_buff *skb;
6055 struct rtmsg *rtm;
6056 struct flowi6 fl6 = {};
6057 bool fibmatch;
6058
6059 err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
6060 if (err < 0)
6061 goto errout;
6062
6063 err = -EINVAL;
6064 rtm = nlmsg_data(nlh);
6065 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
6066 fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH);
6067
6068 if (tb[RTA_SRC]) {
6069 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
6070 goto errout;
6071
6072 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
6073 }
6074
6075 if (tb[RTA_DST]) {
6076 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
6077 goto errout;
6078
6079 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
6080 }
6081
6082 if (tb[RTA_IIF])
6083 iif = nla_get_u32(tb[RTA_IIF]);
6084
6085 if (tb[RTA_OIF])
6086 oif = nla_get_u32(tb[RTA_OIF]);
6087
6088 if (tb[RTA_MARK])
6089 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
6090
6091 if (tb[RTA_UID])
6092 fl6.flowi6_uid = make_kuid(current_user_ns(),
6093 nla_get_u32(tb[RTA_UID]));
6094 else
6095 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
6096
6097 if (tb[RTA_SPORT])
6098 fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
6099
6100 if (tb[RTA_DPORT])
6101 fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
6102
6103 if (tb[RTA_IP_PROTO]) {
6104 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
6105 &fl6.flowi6_proto, AF_INET6,
6106 extack);
6107 if (err)
6108 goto errout;
6109 }
6110
6111 if (iif) {
6112 struct net_device *dev;
6113 int flags = 0;
6114
6115 rcu_read_lock();
6116
6117 dev = dev_get_by_index_rcu(net, iif);
6118 if (!dev) {
6119 rcu_read_unlock();
6120 err = -ENODEV;
6121 goto errout;
6122 }
6123
6124 fl6.flowi6_iif = iif;
6125
6126 if (!ipv6_addr_any(&fl6.saddr))
6127 flags |= RT6_LOOKUP_F_HAS_SADDR;
6128
6129 dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
6130
6131 rcu_read_unlock();
6132 } else {
6133 fl6.flowi6_oif = oif;
6134
6135 dst = ip6_route_output(net, NULL, &fl6);
6136 }
6137
6138
6139 rt = dst_rt6_info(dst);
6140 if (rt->dst.error) {
6141 err = rt->dst.error;
6142 ip6_rt_put(rt);
6143 goto errout;
6144 }
6145
6146 if (rt == net->ipv6.ip6_null_entry) {
6147 err = rt->dst.error;
6148 ip6_rt_put(rt);
6149 goto errout;
6150 }
6151
6152 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
6153 if (!skb) {
6154 ip6_rt_put(rt);
6155 err = -ENOBUFS;
6156 goto errout;
6157 }
6158
6159 skb_dst_set(skb, &rt->dst);
6160
6161 rcu_read_lock();
6162 from = rcu_dereference(rt->from);
6163 if (from) {
6164 if (fibmatch)
6165 err = rt6_fill_node(net, skb, from, NULL, NULL, NULL,
6166 iif, RTM_NEWROUTE,
6167 NETLINK_CB(in_skb).portid,
6168 nlh->nlmsg_seq, 0);
6169 else
6170 err = rt6_fill_node(net, skb, from, dst, &fl6.daddr,
6171 &fl6.saddr, iif, RTM_NEWROUTE,
6172 NETLINK_CB(in_skb).portid,
6173 nlh->nlmsg_seq, 0);
6174 } else {
6175 err = -ENETUNREACH;
6176 }
6177 rcu_read_unlock();
6178
6179 if (err < 0) {
6180 kfree_skb(skb);
6181 goto errout;
6182 }
6183
6184 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
6185errout:
6186 return err;
6187}
6188
6189void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
6190 unsigned int nlm_flags)
6191{
6192 struct sk_buff *skb;
6193 struct net *net = info->nl_net;
6194 u32 seq;
6195 int err;
6196
6197 err = -ENOBUFS;
6198 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
6199
6200 skb = nlmsg_new(rt6_nlmsg_size(rt), GFP_ATOMIC);
6201 if (!skb)
6202 goto errout;
6203
6204 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
6205 event, info->portid, seq, nlm_flags);
6206 if (err < 0) {
6207 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
6208 WARN_ON(err == -EMSGSIZE);
6209 kfree_skb(skb);
6210 goto errout;
6211 }
6212 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
6213 info->nlh, GFP_ATOMIC);
6214 return;
6215errout:
6216 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6217}
6218
6219void fib6_rt_update(struct net *net, struct fib6_info *rt,
6220 struct nl_info *info)
6221{
6222 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
6223 struct sk_buff *skb;
6224 int err = -ENOBUFS;
6225
6226 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
6227 if (!skb)
6228 goto errout;
6229
6230 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
6231 RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
6232 if (err < 0) {
6233 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
6234 WARN_ON(err == -EMSGSIZE);
6235 kfree_skb(skb);
6236 goto errout;
6237 }
6238 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
6239 info->nlh, gfp_any());
6240 return;
6241errout:
6242 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6243}
6244
6245void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
6246 bool offload, bool trap, bool offload_failed)
6247{
6248 struct sk_buff *skb;
6249 int err;
6250
6251 if (READ_ONCE(f6i->offload) == offload &&
6252 READ_ONCE(f6i->trap) == trap &&
6253 READ_ONCE(f6i->offload_failed) == offload_failed)
6254 return;
6255
6256 WRITE_ONCE(f6i->offload, offload);
6257 WRITE_ONCE(f6i->trap, trap);
6258
6259 /* 2 means send notifications only if offload_failed was changed. */
6260 if (net->ipv6.sysctl.fib_notify_on_flag_change == 2 &&
6261 READ_ONCE(f6i->offload_failed) == offload_failed)
6262 return;
6263
6264 WRITE_ONCE(f6i->offload_failed, offload_failed);
6265
6266 if (!rcu_access_pointer(f6i->fib6_node))
6267 /* The route was removed from the tree, do not send
6268 * notification.
6269 */
6270 return;
6271
6272 if (!net->ipv6.sysctl.fib_notify_on_flag_change)
6273 return;
6274
6275 skb = nlmsg_new(rt6_nlmsg_size(f6i), GFP_KERNEL);
6276 if (!skb) {
6277 err = -ENOBUFS;
6278 goto errout;
6279 }
6280
6281 err = rt6_fill_node(net, skb, f6i, NULL, NULL, NULL, 0, RTM_NEWROUTE, 0,
6282 0, 0);
6283 if (err < 0) {
6284 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
6285 WARN_ON(err == -EMSGSIZE);
6286 kfree_skb(skb);
6287 goto errout;
6288 }
6289
6290 rtnl_notify(skb, net, 0, RTNLGRP_IPV6_ROUTE, NULL, GFP_KERNEL);
6291 return;
6292
6293errout:
6294 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6295}
6296EXPORT_SYMBOL(fib6_info_hw_flags_set);
6297
6298static int ip6_route_dev_notify(struct notifier_block *this,
6299 unsigned long event, void *ptr)
6300{
6301 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
6302 struct net *net = dev_net(dev);
6303
6304 if (!(dev->flags & IFF_LOOPBACK))
6305 return NOTIFY_OK;
6306
6307 if (event == NETDEV_REGISTER) {
6308 net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev;
6309 net->ipv6.ip6_null_entry->dst.dev = dev;
6310 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
6311#ifdef CONFIG_IPV6_MULTIPLE_TABLES
6312 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
6313 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
6314 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
6315 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
6316#endif
6317 } else if (event == NETDEV_UNREGISTER &&
6318 dev->reg_state != NETREG_UNREGISTERED) {
6319 /* NETDEV_UNREGISTER could be fired for multiple times by
6320 * netdev_wait_allrefs(). Make sure we only call this once.
6321 */
6322 in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
6323#ifdef CONFIG_IPV6_MULTIPLE_TABLES
6324 in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
6325 in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
6326#endif
6327 }
6328
6329 return NOTIFY_OK;
6330}
6331
6332/*
6333 * /proc
6334 */
6335
6336#ifdef CONFIG_PROC_FS
6337static int rt6_stats_seq_show(struct seq_file *seq, void *v)
6338{
6339 struct net *net = (struct net *)seq->private;
6340 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
6341 net->ipv6.rt6_stats->fib_nodes,
6342 net->ipv6.rt6_stats->fib_route_nodes,
6343 atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
6344 net->ipv6.rt6_stats->fib_rt_entries,
6345 net->ipv6.rt6_stats->fib_rt_cache,
6346 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
6347 net->ipv6.rt6_stats->fib_discarded_routes);
6348
6349 return 0;
6350}
6351#endif /* CONFIG_PROC_FS */
6352
6353#ifdef CONFIG_SYSCTL
6354
6355static int ipv6_sysctl_rtcache_flush(const struct ctl_table *ctl, int write,
6356 void *buffer, size_t *lenp, loff_t *ppos)
6357{
6358 struct net *net;
6359 int delay;
6360 int ret;
6361 if (!write)
6362 return -EINVAL;
6363
6364 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6365 if (ret)
6366 return ret;
6367
6368 net = (struct net *)ctl->extra1;
6369 delay = net->ipv6.sysctl.flush_delay;
6370 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
6371 return 0;
6372}
6373
6374static struct ctl_table ipv6_route_table_template[] = {
6375 {
6376 .procname = "max_size",
6377 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
6378 .maxlen = sizeof(int),
6379 .mode = 0644,
6380 .proc_handler = proc_dointvec,
6381 },
6382 {
6383 .procname = "gc_thresh",
6384 .data = &ip6_dst_ops_template.gc_thresh,
6385 .maxlen = sizeof(int),
6386 .mode = 0644,
6387 .proc_handler = proc_dointvec,
6388 },
6389 {
6390 .procname = "flush",
6391 .data = &init_net.ipv6.sysctl.flush_delay,
6392 .maxlen = sizeof(int),
6393 .mode = 0200,
6394 .proc_handler = ipv6_sysctl_rtcache_flush
6395 },
6396 {
6397 .procname = "gc_min_interval",
6398 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6399 .maxlen = sizeof(int),
6400 .mode = 0644,
6401 .proc_handler = proc_dointvec_jiffies,
6402 },
6403 {
6404 .procname = "gc_timeout",
6405 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
6406 .maxlen = sizeof(int),
6407 .mode = 0644,
6408 .proc_handler = proc_dointvec_jiffies,
6409 },
6410 {
6411 .procname = "gc_interval",
6412 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
6413 .maxlen = sizeof(int),
6414 .mode = 0644,
6415 .proc_handler = proc_dointvec_jiffies,
6416 },
6417 {
6418 .procname = "gc_elasticity",
6419 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
6420 .maxlen = sizeof(int),
6421 .mode = 0644,
6422 .proc_handler = proc_dointvec,
6423 },
6424 {
6425 .procname = "mtu_expires",
6426 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
6427 .maxlen = sizeof(int),
6428 .mode = 0644,
6429 .proc_handler = proc_dointvec_jiffies,
6430 },
6431 {
6432 .procname = "min_adv_mss",
6433 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
6434 .maxlen = sizeof(int),
6435 .mode = 0644,
6436 .proc_handler = proc_dointvec,
6437 },
6438 {
6439 .procname = "gc_min_interval_ms",
6440 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6441 .maxlen = sizeof(int),
6442 .mode = 0644,
6443 .proc_handler = proc_dointvec_ms_jiffies,
6444 },
6445 {
6446 .procname = "skip_notify_on_dev_down",
6447 .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down,
6448 .maxlen = sizeof(u8),
6449 .mode = 0644,
6450 .proc_handler = proc_dou8vec_minmax,
6451 .extra1 = SYSCTL_ZERO,
6452 .extra2 = SYSCTL_ONE,
6453 },
6454};
6455
6456struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
6457{
6458 struct ctl_table *table;
6459
6460 table = kmemdup(ipv6_route_table_template,
6461 sizeof(ipv6_route_table_template),
6462 GFP_KERNEL);
6463
6464 if (table) {
6465 table[0].data = &net->ipv6.sysctl.ip6_rt_max_size;
6466 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
6467 table[2].data = &net->ipv6.sysctl.flush_delay;
6468 table[2].extra1 = net;
6469 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6470 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
6471 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
6472 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
6473 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
6474 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
6475 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6476 table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
6477 }
6478
6479 return table;
6480}
6481
6482size_t ipv6_route_sysctl_table_size(struct net *net)
6483{
6484 /* Don't export sysctls to unprivileged users */
6485 if (net->user_ns != &init_user_ns)
6486 return 1;
6487
6488 return ARRAY_SIZE(ipv6_route_table_template);
6489}
6490#endif
6491
6492static int __net_init ip6_route_net_init(struct net *net)
6493{
6494 int ret = -ENOMEM;
6495
6496 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
6497 sizeof(net->ipv6.ip6_dst_ops));
6498
6499 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
6500 goto out_ip6_dst_ops;
6501
6502 net->ipv6.fib6_null_entry = fib6_info_alloc(GFP_KERNEL, true);
6503 if (!net->ipv6.fib6_null_entry)
6504 goto out_ip6_dst_entries;
6505 memcpy(net->ipv6.fib6_null_entry, &fib6_null_entry_template,
6506 sizeof(*net->ipv6.fib6_null_entry));
6507
6508 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
6509 sizeof(*net->ipv6.ip6_null_entry),
6510 GFP_KERNEL);
6511 if (!net->ipv6.ip6_null_entry)
6512 goto out_fib6_null_entry;
6513 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6514 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
6515 ip6_template_metrics, true);
6516 INIT_LIST_HEAD(&net->ipv6.ip6_null_entry->dst.rt_uncached);
6517
6518#ifdef CONFIG_IPV6_MULTIPLE_TABLES
6519 net->ipv6.fib6_has_custom_rules = false;
6520 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
6521 sizeof(*net->ipv6.ip6_prohibit_entry),
6522 GFP_KERNEL);
6523 if (!net->ipv6.ip6_prohibit_entry)
6524 goto out_ip6_null_entry;
6525 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6526 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
6527 ip6_template_metrics, true);
6528 INIT_LIST_HEAD(&net->ipv6.ip6_prohibit_entry->dst.rt_uncached);
6529
6530 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
6531 sizeof(*net->ipv6.ip6_blk_hole_entry),
6532 GFP_KERNEL);
6533 if (!net->ipv6.ip6_blk_hole_entry)
6534 goto out_ip6_prohibit_entry;
6535 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6536 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
6537 ip6_template_metrics, true);
6538 INIT_LIST_HEAD(&net->ipv6.ip6_blk_hole_entry->dst.rt_uncached);
6539#ifdef CONFIG_IPV6_SUBTREES
6540 net->ipv6.fib6_routes_require_src = 0;
6541#endif
6542#endif
6543
6544 net->ipv6.sysctl.flush_delay = 0;
6545 net->ipv6.sysctl.ip6_rt_max_size = INT_MAX;
6546 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
6547 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
6548 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
6549 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
6550 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
6551 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
6552 net->ipv6.sysctl.skip_notify_on_dev_down = 0;
6553
6554 atomic_set(&net->ipv6.ip6_rt_gc_expire, 30*HZ);
6555
6556 ret = 0;
6557out:
6558 return ret;
6559
6560#ifdef CONFIG_IPV6_MULTIPLE_TABLES
6561out_ip6_prohibit_entry:
6562 kfree(net->ipv6.ip6_prohibit_entry);
6563out_ip6_null_entry:
6564 kfree(net->ipv6.ip6_null_entry);
6565#endif
6566out_fib6_null_entry:
6567 kfree(net->ipv6.fib6_null_entry);
6568out_ip6_dst_entries:
6569 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6570out_ip6_dst_ops:
6571 goto out;
6572}
6573
6574static void __net_exit ip6_route_net_exit(struct net *net)
6575{
6576 kfree(net->ipv6.fib6_null_entry);
6577 kfree(net->ipv6.ip6_null_entry);
6578#ifdef CONFIG_IPV6_MULTIPLE_TABLES
6579 kfree(net->ipv6.ip6_prohibit_entry);
6580 kfree(net->ipv6.ip6_blk_hole_entry);
6581#endif
6582 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6583}
6584
6585static int __net_init ip6_route_net_init_late(struct net *net)
6586{
6587#ifdef CONFIG_PROC_FS
6588 if (!proc_create_net("ipv6_route", 0, net->proc_net,
6589 &ipv6_route_seq_ops,
6590 sizeof(struct ipv6_route_iter)))
6591 return -ENOMEM;
6592
6593 if (!proc_create_net_single("rt6_stats", 0444, net->proc_net,
6594 rt6_stats_seq_show, NULL)) {
6595 remove_proc_entry("ipv6_route", net->proc_net);
6596 return -ENOMEM;
6597 }
6598#endif
6599 return 0;
6600}
6601
6602static void __net_exit ip6_route_net_exit_late(struct net *net)
6603{
6604#ifdef CONFIG_PROC_FS
6605 remove_proc_entry("ipv6_route", net->proc_net);
6606 remove_proc_entry("rt6_stats", net->proc_net);
6607#endif
6608}
6609
6610static struct pernet_operations ip6_route_net_ops = {
6611 .init = ip6_route_net_init,
6612 .exit = ip6_route_net_exit,
6613};
6614
6615static int __net_init ipv6_inetpeer_init(struct net *net)
6616{
6617 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
6618
6619 if (!bp)
6620 return -ENOMEM;
6621 inet_peer_base_init(bp);
6622 net->ipv6.peers = bp;
6623 return 0;
6624}
6625
6626static void __net_exit ipv6_inetpeer_exit(struct net *net)
6627{
6628 struct inet_peer_base *bp = net->ipv6.peers;
6629
6630 net->ipv6.peers = NULL;
6631 inetpeer_invalidate_tree(bp);
6632 kfree(bp);
6633}
6634
6635static struct pernet_operations ipv6_inetpeer_ops = {
6636 .init = ipv6_inetpeer_init,
6637 .exit = ipv6_inetpeer_exit,
6638};
6639
6640static struct pernet_operations ip6_route_net_late_ops = {
6641 .init = ip6_route_net_init_late,
6642 .exit = ip6_route_net_exit_late,
6643};
6644
6645static struct notifier_block ip6_route_dev_notifier = {
6646 .notifier_call = ip6_route_dev_notify,
6647 .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
6648};
6649
6650void __init ip6_route_init_special_entries(void)
6651{
6652 /* Registering of the loopback is done before this portion of code,
6653 * the loopback reference in rt6_info will not be taken, do it
6654 * manually for init_net */
6655 init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev;
6656 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
6657 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6658 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6659 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
6660 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6661 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
6662 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6663 #endif
6664}
6665
6666#if IS_BUILTIN(CONFIG_IPV6)
6667#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
6668DEFINE_BPF_ITER_FUNC(ipv6_route, struct bpf_iter_meta *meta, struct fib6_info *rt)
6669
6670BTF_ID_LIST(btf_fib6_info_id)
6671BTF_ID(struct, fib6_info)
6672
6673static const struct bpf_iter_seq_info ipv6_route_seq_info = {
6674 .seq_ops = &ipv6_route_seq_ops,
6675 .init_seq_private = bpf_iter_init_seq_net,
6676 .fini_seq_private = bpf_iter_fini_seq_net,
6677 .seq_priv_size = sizeof(struct ipv6_route_iter),
6678};
6679
6680static struct bpf_iter_reg ipv6_route_reg_info = {
6681 .target = "ipv6_route",
6682 .ctx_arg_info_size = 1,
6683 .ctx_arg_info = {
6684 { offsetof(struct bpf_iter__ipv6_route, rt),
6685 PTR_TO_BTF_ID_OR_NULL },
6686 },
6687 .seq_info = &ipv6_route_seq_info,
6688};
6689
6690static int __init bpf_iter_register(void)
6691{
6692 ipv6_route_reg_info.ctx_arg_info[0].btf_id = *btf_fib6_info_id;
6693 return bpf_iter_reg_target(&ipv6_route_reg_info);
6694}
6695
6696static void bpf_iter_unregister(void)
6697{
6698 bpf_iter_unreg_target(&ipv6_route_reg_info);
6699}
6700#endif
6701#endif
6702
6703static const struct rtnl_msg_handler ip6_route_rtnl_msg_handlers[] __initconst_or_module = {
6704 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWROUTE,
6705 .doit = inet6_rtm_newroute},
6706 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELROUTE,
6707 .doit = inet6_rtm_delroute},
6708 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETROUTE,
6709 .doit = inet6_rtm_getroute, .flags = RTNL_FLAG_DOIT_UNLOCKED},
6710};
6711
6712int __init ip6_route_init(void)
6713{
6714 int ret;
6715 int cpu;
6716
6717 ret = -ENOMEM;
6718 ip6_dst_ops_template.kmem_cachep =
6719 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
6720 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL);
6721 if (!ip6_dst_ops_template.kmem_cachep)
6722 goto out;
6723
6724 ret = dst_entries_init(&ip6_dst_blackhole_ops);
6725 if (ret)
6726 goto out_kmem_cache;
6727
6728 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
6729 if (ret)
6730 goto out_dst_entries;
6731
6732 ret = register_pernet_subsys(&ip6_route_net_ops);
6733 if (ret)
6734 goto out_register_inetpeer;
6735
6736 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
6737
6738 ret = fib6_init();
6739 if (ret)
6740 goto out_register_subsys;
6741
6742 ret = xfrm6_init();
6743 if (ret)
6744 goto out_fib6_init;
6745
6746 ret = fib6_rules_init();
6747 if (ret)
6748 goto xfrm6_init;
6749
6750 ret = register_pernet_subsys(&ip6_route_net_late_ops);
6751 if (ret)
6752 goto fib6_rules_init;
6753
6754 ret = rtnl_register_many(ip6_route_rtnl_msg_handlers);
6755 if (ret < 0)
6756 goto out_register_late_subsys;
6757
6758 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
6759 if (ret)
6760 goto out_register_late_subsys;
6761
6762#if IS_BUILTIN(CONFIG_IPV6)
6763#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
6764 ret = bpf_iter_register();
6765 if (ret)
6766 goto out_register_late_subsys;
6767#endif
6768#endif
6769
6770 for_each_possible_cpu(cpu) {
6771 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
6772
6773 INIT_LIST_HEAD(&ul->head);
6774 spin_lock_init(&ul->lock);
6775 }
6776
6777out:
6778 return ret;
6779
6780out_register_late_subsys:
6781 rtnl_unregister_all(PF_INET6);
6782 unregister_pernet_subsys(&ip6_route_net_late_ops);
6783fib6_rules_init:
6784 fib6_rules_cleanup();
6785xfrm6_init:
6786 xfrm6_fini();
6787out_fib6_init:
6788 fib6_gc_cleanup();
6789out_register_subsys:
6790 unregister_pernet_subsys(&ip6_route_net_ops);
6791out_register_inetpeer:
6792 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6793out_dst_entries:
6794 dst_entries_destroy(&ip6_dst_blackhole_ops);
6795out_kmem_cache:
6796 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6797 goto out;
6798}
6799
6800void ip6_route_cleanup(void)
6801{
6802#if IS_BUILTIN(CONFIG_IPV6)
6803#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
6804 bpf_iter_unregister();
6805#endif
6806#endif
6807 unregister_netdevice_notifier(&ip6_route_dev_notifier);
6808 unregister_pernet_subsys(&ip6_route_net_late_ops);
6809 fib6_rules_cleanup();
6810 xfrm6_fini();
6811 fib6_gc_cleanup();
6812 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6813 unregister_pernet_subsys(&ip6_route_net_ops);
6814 dst_entries_destroy(&ip6_dst_blackhole_ops);
6815 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6816}
1/*
2 * Linux INET6 implementation
3 * FIB front-end.
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
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.
12 */
13
14/* Changes:
15 *
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.
25 */
26
27#include <linux/capability.h>
28#include <linux/errno.h>
29#include <linux/types.h>
30#include <linux/times.h>
31#include <linux/socket.h>
32#include <linux/sockios.h>
33#include <linux/net.h>
34#include <linux/route.h>
35#include <linux/netdevice.h>
36#include <linux/in6.h>
37#include <linux/mroute6.h>
38#include <linux/init.h>
39#include <linux/if_arp.h>
40#include <linux/proc_fs.h>
41#include <linux/seq_file.h>
42#include <linux/nsproxy.h>
43#include <linux/slab.h>
44#include <net/net_namespace.h>
45#include <net/snmp.h>
46#include <net/ipv6.h>
47#include <net/ip6_fib.h>
48#include <net/ip6_route.h>
49#include <net/ndisc.h>
50#include <net/addrconf.h>
51#include <net/tcp.h>
52#include <linux/rtnetlink.h>
53#include <net/dst.h>
54#include <net/xfrm.h>
55#include <net/netevent.h>
56#include <net/netlink.h>
57
58#include <asm/uaccess.h>
59
60#ifdef CONFIG_SYSCTL
61#include <linux/sysctl.h>
62#endif
63
64/* Set to 3 to get tracing. */
65#define RT6_DEBUG 2
66
67#if RT6_DEBUG >= 3
68#define RDBG(x) printk x
69#define RT6_TRACE(x...) printk(KERN_DEBUG x)
70#else
71#define RDBG(x)
72#define RT6_TRACE(x...) do { ; } while (0)
73#endif
74
75static struct rt6_info *ip6_rt_copy(const struct rt6_info *ort,
76 const struct in6_addr *dest);
77static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
78static unsigned int ip6_default_advmss(const struct dst_entry *dst);
79static unsigned int ip6_default_mtu(const struct dst_entry *dst);
80static struct dst_entry *ip6_negative_advice(struct dst_entry *);
81static void ip6_dst_destroy(struct dst_entry *);
82static void ip6_dst_ifdown(struct dst_entry *,
83 struct net_device *dev, int how);
84static int ip6_dst_gc(struct dst_ops *ops);
85
86static int ip6_pkt_discard(struct sk_buff *skb);
87static int ip6_pkt_discard_out(struct sk_buff *skb);
88static void ip6_link_failure(struct sk_buff *skb);
89static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
90
91#ifdef CONFIG_IPV6_ROUTE_INFO
92static struct rt6_info *rt6_add_route_info(struct net *net,
93 const struct in6_addr *prefix, int prefixlen,
94 const struct in6_addr *gwaddr, int ifindex,
95 unsigned pref);
96static struct rt6_info *rt6_get_route_info(struct net *net,
97 const struct in6_addr *prefix, int prefixlen,
98 const struct in6_addr *gwaddr, int ifindex);
99#endif
100
101static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
102{
103 struct rt6_info *rt = (struct rt6_info *) dst;
104 struct inet_peer *peer;
105 u32 *p = NULL;
106
107 if (!(rt->dst.flags & DST_HOST))
108 return NULL;
109
110 if (!rt->rt6i_peer)
111 rt6_bind_peer(rt, 1);
112
113 peer = rt->rt6i_peer;
114 if (peer) {
115 u32 *old_p = __DST_METRICS_PTR(old);
116 unsigned long prev, new;
117
118 p = peer->metrics;
119 if (inet_metrics_new(peer))
120 memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
121
122 new = (unsigned long) p;
123 prev = cmpxchg(&dst->_metrics, old, new);
124
125 if (prev != old) {
126 p = __DST_METRICS_PTR(prev);
127 if (prev & DST_METRICS_READ_ONLY)
128 p = NULL;
129 }
130 }
131 return p;
132}
133
134static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, const void *daddr)
135{
136 return __neigh_lookup_errno(&nd_tbl, daddr, dst->dev);
137}
138
139static struct dst_ops ip6_dst_ops_template = {
140 .family = AF_INET6,
141 .protocol = cpu_to_be16(ETH_P_IPV6),
142 .gc = ip6_dst_gc,
143 .gc_thresh = 1024,
144 .check = ip6_dst_check,
145 .default_advmss = ip6_default_advmss,
146 .default_mtu = ip6_default_mtu,
147 .cow_metrics = ipv6_cow_metrics,
148 .destroy = ip6_dst_destroy,
149 .ifdown = ip6_dst_ifdown,
150 .negative_advice = ip6_negative_advice,
151 .link_failure = ip6_link_failure,
152 .update_pmtu = ip6_rt_update_pmtu,
153 .local_out = __ip6_local_out,
154 .neigh_lookup = ip6_neigh_lookup,
155};
156
157static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
158{
159 return 0;
160}
161
162static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
163{
164}
165
166static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
167 unsigned long old)
168{
169 return NULL;
170}
171
172static struct dst_ops ip6_dst_blackhole_ops = {
173 .family = AF_INET6,
174 .protocol = cpu_to_be16(ETH_P_IPV6),
175 .destroy = ip6_dst_destroy,
176 .check = ip6_dst_check,
177 .default_mtu = ip6_blackhole_default_mtu,
178 .default_advmss = ip6_default_advmss,
179 .update_pmtu = ip6_rt_blackhole_update_pmtu,
180 .cow_metrics = ip6_rt_blackhole_cow_metrics,
181 .neigh_lookup = ip6_neigh_lookup,
182};
183
184static const u32 ip6_template_metrics[RTAX_MAX] = {
185 [RTAX_HOPLIMIT - 1] = 255,
186};
187
188static struct rt6_info ip6_null_entry_template = {
189 .dst = {
190 .__refcnt = ATOMIC_INIT(1),
191 .__use = 1,
192 .obsolete = -1,
193 .error = -ENETUNREACH,
194 .input = ip6_pkt_discard,
195 .output = ip6_pkt_discard_out,
196 },
197 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
198 .rt6i_protocol = RTPROT_KERNEL,
199 .rt6i_metric = ~(u32) 0,
200 .rt6i_ref = ATOMIC_INIT(1),
201};
202
203#ifdef CONFIG_IPV6_MULTIPLE_TABLES
204
205static int ip6_pkt_prohibit(struct sk_buff *skb);
206static int ip6_pkt_prohibit_out(struct sk_buff *skb);
207
208static struct rt6_info ip6_prohibit_entry_template = {
209 .dst = {
210 .__refcnt = ATOMIC_INIT(1),
211 .__use = 1,
212 .obsolete = -1,
213 .error = -EACCES,
214 .input = ip6_pkt_prohibit,
215 .output = ip6_pkt_prohibit_out,
216 },
217 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
218 .rt6i_protocol = RTPROT_KERNEL,
219 .rt6i_metric = ~(u32) 0,
220 .rt6i_ref = ATOMIC_INIT(1),
221};
222
223static struct rt6_info ip6_blk_hole_entry_template = {
224 .dst = {
225 .__refcnt = ATOMIC_INIT(1),
226 .__use = 1,
227 .obsolete = -1,
228 .error = -EINVAL,
229 .input = dst_discard,
230 .output = dst_discard,
231 },
232 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
233 .rt6i_protocol = RTPROT_KERNEL,
234 .rt6i_metric = ~(u32) 0,
235 .rt6i_ref = ATOMIC_INIT(1),
236};
237
238#endif
239
240/* allocate dst with ip6_dst_ops */
241static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops,
242 struct net_device *dev,
243 int flags)
244{
245 struct rt6_info *rt = dst_alloc(ops, dev, 0, 0, flags);
246
247 if (rt != NULL)
248 memset(&rt->rt6i_table, 0,
249 sizeof(*rt) - sizeof(struct dst_entry));
250
251 return rt;
252}
253
254static void ip6_dst_destroy(struct dst_entry *dst)
255{
256 struct rt6_info *rt = (struct rt6_info *)dst;
257 struct inet6_dev *idev = rt->rt6i_idev;
258 struct inet_peer *peer = rt->rt6i_peer;
259
260 if (!(rt->dst.flags & DST_HOST))
261 dst_destroy_metrics_generic(dst);
262
263 if (idev != NULL) {
264 rt->rt6i_idev = NULL;
265 in6_dev_put(idev);
266 }
267 if (peer) {
268 rt->rt6i_peer = NULL;
269 inet_putpeer(peer);
270 }
271}
272
273static atomic_t __rt6_peer_genid = ATOMIC_INIT(0);
274
275static u32 rt6_peer_genid(void)
276{
277 return atomic_read(&__rt6_peer_genid);
278}
279
280void rt6_bind_peer(struct rt6_info *rt, int create)
281{
282 struct inet_peer *peer;
283
284 peer = inet_getpeer_v6(&rt->rt6i_dst.addr, create);
285 if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
286 inet_putpeer(peer);
287 else
288 rt->rt6i_peer_genid = rt6_peer_genid();
289}
290
291static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
292 int how)
293{
294 struct rt6_info *rt = (struct rt6_info *)dst;
295 struct inet6_dev *idev = rt->rt6i_idev;
296 struct net_device *loopback_dev =
297 dev_net(dev)->loopback_dev;
298
299 if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
300 struct inet6_dev *loopback_idev =
301 in6_dev_get(loopback_dev);
302 if (loopback_idev != NULL) {
303 rt->rt6i_idev = loopback_idev;
304 in6_dev_put(idev);
305 }
306 }
307}
308
309static __inline__ int rt6_check_expired(const struct rt6_info *rt)
310{
311 return (rt->rt6i_flags & RTF_EXPIRES) &&
312 time_after(jiffies, rt->rt6i_expires);
313}
314
315static inline int rt6_need_strict(const struct in6_addr *daddr)
316{
317 return ipv6_addr_type(daddr) &
318 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
319}
320
321/*
322 * Route lookup. Any table->tb6_lock is implied.
323 */
324
325static inline struct rt6_info *rt6_device_match(struct net *net,
326 struct rt6_info *rt,
327 const struct in6_addr *saddr,
328 int oif,
329 int flags)
330{
331 struct rt6_info *local = NULL;
332 struct rt6_info *sprt;
333
334 if (!oif && ipv6_addr_any(saddr))
335 goto out;
336
337 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
338 struct net_device *dev = sprt->rt6i_dev;
339
340 if (oif) {
341 if (dev->ifindex == oif)
342 return sprt;
343 if (dev->flags & IFF_LOOPBACK) {
344 if (sprt->rt6i_idev == NULL ||
345 sprt->rt6i_idev->dev->ifindex != oif) {
346 if (flags & RT6_LOOKUP_F_IFACE && oif)
347 continue;
348 if (local && (!oif ||
349 local->rt6i_idev->dev->ifindex == oif))
350 continue;
351 }
352 local = sprt;
353 }
354 } else {
355 if (ipv6_chk_addr(net, saddr, dev,
356 flags & RT6_LOOKUP_F_IFACE))
357 return sprt;
358 }
359 }
360
361 if (oif) {
362 if (local)
363 return local;
364
365 if (flags & RT6_LOOKUP_F_IFACE)
366 return net->ipv6.ip6_null_entry;
367 }
368out:
369 return rt;
370}
371
372#ifdef CONFIG_IPV6_ROUTER_PREF
373static void rt6_probe(struct rt6_info *rt)
374{
375 struct neighbour *neigh;
376 /*
377 * Okay, this does not seem to be appropriate
378 * for now, however, we need to check if it
379 * is really so; aka Router Reachability Probing.
380 *
381 * Router Reachability Probe MUST be rate-limited
382 * to no more than one per minute.
383 */
384 rcu_read_lock();
385 neigh = rt ? dst_get_neighbour(&rt->dst) : NULL;
386 if (!neigh || (neigh->nud_state & NUD_VALID))
387 goto out;
388 read_lock_bh(&neigh->lock);
389 if (!(neigh->nud_state & NUD_VALID) &&
390 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
391 struct in6_addr mcaddr;
392 struct in6_addr *target;
393
394 neigh->updated = jiffies;
395 read_unlock_bh(&neigh->lock);
396
397 target = (struct in6_addr *)&neigh->primary_key;
398 addrconf_addr_solict_mult(target, &mcaddr);
399 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
400 } else {
401 read_unlock_bh(&neigh->lock);
402 }
403out:
404 rcu_read_unlock();
405}
406#else
407static inline void rt6_probe(struct rt6_info *rt)
408{
409}
410#endif
411
412/*
413 * Default Router Selection (RFC 2461 6.3.6)
414 */
415static inline int rt6_check_dev(struct rt6_info *rt, int oif)
416{
417 struct net_device *dev = rt->rt6i_dev;
418 if (!oif || dev->ifindex == oif)
419 return 2;
420 if ((dev->flags & IFF_LOOPBACK) &&
421 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
422 return 1;
423 return 0;
424}
425
426static inline int rt6_check_neigh(struct rt6_info *rt)
427{
428 struct neighbour *neigh;
429 int m;
430
431 rcu_read_lock();
432 neigh = dst_get_neighbour(&rt->dst);
433 if (rt->rt6i_flags & RTF_NONEXTHOP ||
434 !(rt->rt6i_flags & RTF_GATEWAY))
435 m = 1;
436 else if (neigh) {
437 read_lock_bh(&neigh->lock);
438 if (neigh->nud_state & NUD_VALID)
439 m = 2;
440#ifdef CONFIG_IPV6_ROUTER_PREF
441 else if (neigh->nud_state & NUD_FAILED)
442 m = 0;
443#endif
444 else
445 m = 1;
446 read_unlock_bh(&neigh->lock);
447 } else
448 m = 0;
449 rcu_read_unlock();
450 return m;
451}
452
453static int rt6_score_route(struct rt6_info *rt, int oif,
454 int strict)
455{
456 int m, n;
457
458 m = rt6_check_dev(rt, oif);
459 if (!m && (strict & RT6_LOOKUP_F_IFACE))
460 return -1;
461#ifdef CONFIG_IPV6_ROUTER_PREF
462 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
463#endif
464 n = rt6_check_neigh(rt);
465 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
466 return -1;
467 return m;
468}
469
470static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
471 int *mpri, struct rt6_info *match)
472{
473 int m;
474
475 if (rt6_check_expired(rt))
476 goto out;
477
478 m = rt6_score_route(rt, oif, strict);
479 if (m < 0)
480 goto out;
481
482 if (m > *mpri) {
483 if (strict & RT6_LOOKUP_F_REACHABLE)
484 rt6_probe(match);
485 *mpri = m;
486 match = rt;
487 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
488 rt6_probe(rt);
489 }
490
491out:
492 return match;
493}
494
495static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
496 struct rt6_info *rr_head,
497 u32 metric, int oif, int strict)
498{
499 struct rt6_info *rt, *match;
500 int mpri = -1;
501
502 match = NULL;
503 for (rt = rr_head; rt && rt->rt6i_metric == metric;
504 rt = rt->dst.rt6_next)
505 match = find_match(rt, oif, strict, &mpri, match);
506 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
507 rt = rt->dst.rt6_next)
508 match = find_match(rt, oif, strict, &mpri, match);
509
510 return match;
511}
512
513static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
514{
515 struct rt6_info *match, *rt0;
516 struct net *net;
517
518 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
519 __func__, fn->leaf, oif);
520
521 rt0 = fn->rr_ptr;
522 if (!rt0)
523 fn->rr_ptr = rt0 = fn->leaf;
524
525 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
526
527 if (!match &&
528 (strict & RT6_LOOKUP_F_REACHABLE)) {
529 struct rt6_info *next = rt0->dst.rt6_next;
530
531 /* no entries matched; do round-robin */
532 if (!next || next->rt6i_metric != rt0->rt6i_metric)
533 next = fn->leaf;
534
535 if (next != rt0)
536 fn->rr_ptr = next;
537 }
538
539 RT6_TRACE("%s() => %p\n",
540 __func__, match);
541
542 net = dev_net(rt0->rt6i_dev);
543 return match ? match : net->ipv6.ip6_null_entry;
544}
545
546#ifdef CONFIG_IPV6_ROUTE_INFO
547int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
548 const struct in6_addr *gwaddr)
549{
550 struct net *net = dev_net(dev);
551 struct route_info *rinfo = (struct route_info *) opt;
552 struct in6_addr prefix_buf, *prefix;
553 unsigned int pref;
554 unsigned long lifetime;
555 struct rt6_info *rt;
556
557 if (len < sizeof(struct route_info)) {
558 return -EINVAL;
559 }
560
561 /* Sanity check for prefix_len and length */
562 if (rinfo->length > 3) {
563 return -EINVAL;
564 } else if (rinfo->prefix_len > 128) {
565 return -EINVAL;
566 } else if (rinfo->prefix_len > 64) {
567 if (rinfo->length < 2) {
568 return -EINVAL;
569 }
570 } else if (rinfo->prefix_len > 0) {
571 if (rinfo->length < 1) {
572 return -EINVAL;
573 }
574 }
575
576 pref = rinfo->route_pref;
577 if (pref == ICMPV6_ROUTER_PREF_INVALID)
578 return -EINVAL;
579
580 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
581
582 if (rinfo->length == 3)
583 prefix = (struct in6_addr *)rinfo->prefix;
584 else {
585 /* this function is safe */
586 ipv6_addr_prefix(&prefix_buf,
587 (struct in6_addr *)rinfo->prefix,
588 rinfo->prefix_len);
589 prefix = &prefix_buf;
590 }
591
592 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
593 dev->ifindex);
594
595 if (rt && !lifetime) {
596 ip6_del_rt(rt);
597 rt = NULL;
598 }
599
600 if (!rt && lifetime)
601 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
602 pref);
603 else if (rt)
604 rt->rt6i_flags = RTF_ROUTEINFO |
605 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
606
607 if (rt) {
608 if (!addrconf_finite_timeout(lifetime)) {
609 rt->rt6i_flags &= ~RTF_EXPIRES;
610 } else {
611 rt->rt6i_expires = jiffies + HZ * lifetime;
612 rt->rt6i_flags |= RTF_EXPIRES;
613 }
614 dst_release(&rt->dst);
615 }
616 return 0;
617}
618#endif
619
620#define BACKTRACK(__net, saddr) \
621do { \
622 if (rt == __net->ipv6.ip6_null_entry) { \
623 struct fib6_node *pn; \
624 while (1) { \
625 if (fn->fn_flags & RTN_TL_ROOT) \
626 goto out; \
627 pn = fn->parent; \
628 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
629 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
630 else \
631 fn = pn; \
632 if (fn->fn_flags & RTN_RTINFO) \
633 goto restart; \
634 } \
635 } \
636} while(0)
637
638static struct rt6_info *ip6_pol_route_lookup(struct net *net,
639 struct fib6_table *table,
640 struct flowi6 *fl6, int flags)
641{
642 struct fib6_node *fn;
643 struct rt6_info *rt;
644
645 read_lock_bh(&table->tb6_lock);
646 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
647restart:
648 rt = fn->leaf;
649 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
650 BACKTRACK(net, &fl6->saddr);
651out:
652 dst_use(&rt->dst, jiffies);
653 read_unlock_bh(&table->tb6_lock);
654 return rt;
655
656}
657
658struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
659 const struct in6_addr *saddr, int oif, int strict)
660{
661 struct flowi6 fl6 = {
662 .flowi6_oif = oif,
663 .daddr = *daddr,
664 };
665 struct dst_entry *dst;
666 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
667
668 if (saddr) {
669 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
670 flags |= RT6_LOOKUP_F_HAS_SADDR;
671 }
672
673 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
674 if (dst->error == 0)
675 return (struct rt6_info *) dst;
676
677 dst_release(dst);
678
679 return NULL;
680}
681
682EXPORT_SYMBOL(rt6_lookup);
683
684/* ip6_ins_rt is called with FREE table->tb6_lock.
685 It takes new route entry, the addition fails by any reason the
686 route is freed. In any case, if caller does not hold it, it may
687 be destroyed.
688 */
689
690static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
691{
692 int err;
693 struct fib6_table *table;
694
695 table = rt->rt6i_table;
696 write_lock_bh(&table->tb6_lock);
697 err = fib6_add(&table->tb6_root, rt, info);
698 write_unlock_bh(&table->tb6_lock);
699
700 return err;
701}
702
703int ip6_ins_rt(struct rt6_info *rt)
704{
705 struct nl_info info = {
706 .nl_net = dev_net(rt->rt6i_dev),
707 };
708 return __ip6_ins_rt(rt, &info);
709}
710
711static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort,
712 const struct in6_addr *daddr,
713 const struct in6_addr *saddr)
714{
715 struct rt6_info *rt;
716
717 /*
718 * Clone the route.
719 */
720
721 rt = ip6_rt_copy(ort, daddr);
722
723 if (rt) {
724 struct neighbour *neigh;
725 int attempts = !in_softirq();
726
727 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
728 if (rt->rt6i_dst.plen != 128 &&
729 ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
730 rt->rt6i_flags |= RTF_ANYCAST;
731 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
732 }
733
734 rt->rt6i_flags |= RTF_CACHE;
735
736#ifdef CONFIG_IPV6_SUBTREES
737 if (rt->rt6i_src.plen && saddr) {
738 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
739 rt->rt6i_src.plen = 128;
740 }
741#endif
742
743 retry:
744 neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
745 if (IS_ERR(neigh)) {
746 struct net *net = dev_net(rt->rt6i_dev);
747 int saved_rt_min_interval =
748 net->ipv6.sysctl.ip6_rt_gc_min_interval;
749 int saved_rt_elasticity =
750 net->ipv6.sysctl.ip6_rt_gc_elasticity;
751
752 if (attempts-- > 0) {
753 net->ipv6.sysctl.ip6_rt_gc_elasticity = 1;
754 net->ipv6.sysctl.ip6_rt_gc_min_interval = 0;
755
756 ip6_dst_gc(&net->ipv6.ip6_dst_ops);
757
758 net->ipv6.sysctl.ip6_rt_gc_elasticity =
759 saved_rt_elasticity;
760 net->ipv6.sysctl.ip6_rt_gc_min_interval =
761 saved_rt_min_interval;
762 goto retry;
763 }
764
765 if (net_ratelimit())
766 printk(KERN_WARNING
767 "ipv6: Neighbour table overflow.\n");
768 dst_free(&rt->dst);
769 return NULL;
770 }
771 dst_set_neighbour(&rt->dst, neigh);
772
773 }
774
775 return rt;
776}
777
778static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort,
779 const struct in6_addr *daddr)
780{
781 struct rt6_info *rt = ip6_rt_copy(ort, daddr);
782
783 if (rt) {
784 rt->rt6i_flags |= RTF_CACHE;
785 dst_set_neighbour(&rt->dst, neigh_clone(dst_get_neighbour_raw(&ort->dst)));
786 }
787 return rt;
788}
789
790static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
791 struct flowi6 *fl6, int flags)
792{
793 struct fib6_node *fn;
794 struct rt6_info *rt, *nrt;
795 int strict = 0;
796 int attempts = 3;
797 int err;
798 int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
799
800 strict |= flags & RT6_LOOKUP_F_IFACE;
801
802relookup:
803 read_lock_bh(&table->tb6_lock);
804
805restart_2:
806 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
807
808restart:
809 rt = rt6_select(fn, oif, strict | reachable);
810
811 BACKTRACK(net, &fl6->saddr);
812 if (rt == net->ipv6.ip6_null_entry ||
813 rt->rt6i_flags & RTF_CACHE)
814 goto out;
815
816 dst_hold(&rt->dst);
817 read_unlock_bh(&table->tb6_lock);
818
819 if (!dst_get_neighbour_raw(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
820 nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
821 else if (!(rt->dst.flags & DST_HOST))
822 nrt = rt6_alloc_clone(rt, &fl6->daddr);
823 else
824 goto out2;
825
826 dst_release(&rt->dst);
827 rt = nrt ? : net->ipv6.ip6_null_entry;
828
829 dst_hold(&rt->dst);
830 if (nrt) {
831 err = ip6_ins_rt(nrt);
832 if (!err)
833 goto out2;
834 }
835
836 if (--attempts <= 0)
837 goto out2;
838
839 /*
840 * Race condition! In the gap, when table->tb6_lock was
841 * released someone could insert this route. Relookup.
842 */
843 dst_release(&rt->dst);
844 goto relookup;
845
846out:
847 if (reachable) {
848 reachable = 0;
849 goto restart_2;
850 }
851 dst_hold(&rt->dst);
852 read_unlock_bh(&table->tb6_lock);
853out2:
854 rt->dst.lastuse = jiffies;
855 rt->dst.__use++;
856
857 return rt;
858}
859
860static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
861 struct flowi6 *fl6, int flags)
862{
863 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
864}
865
866void ip6_route_input(struct sk_buff *skb)
867{
868 const struct ipv6hdr *iph = ipv6_hdr(skb);
869 struct net *net = dev_net(skb->dev);
870 int flags = RT6_LOOKUP_F_HAS_SADDR;
871 struct flowi6 fl6 = {
872 .flowi6_iif = skb->dev->ifindex,
873 .daddr = iph->daddr,
874 .saddr = iph->saddr,
875 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
876 .flowi6_mark = skb->mark,
877 .flowi6_proto = iph->nexthdr,
878 };
879
880 if (rt6_need_strict(&iph->daddr) && skb->dev->type != ARPHRD_PIMREG)
881 flags |= RT6_LOOKUP_F_IFACE;
882
883 skb_dst_set(skb, fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_input));
884}
885
886static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
887 struct flowi6 *fl6, int flags)
888{
889 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
890}
891
892struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
893 struct flowi6 *fl6)
894{
895 int flags = 0;
896
897 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
898 flags |= RT6_LOOKUP_F_IFACE;
899
900 if (!ipv6_addr_any(&fl6->saddr))
901 flags |= RT6_LOOKUP_F_HAS_SADDR;
902 else if (sk)
903 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
904
905 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
906}
907
908EXPORT_SYMBOL(ip6_route_output);
909
910struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
911{
912 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
913 struct dst_entry *new = NULL;
914
915 rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, 0, 0);
916 if (rt) {
917 memset(&rt->rt6i_table, 0, sizeof(*rt) - sizeof(struct dst_entry));
918
919 new = &rt->dst;
920
921 new->__use = 1;
922 new->input = dst_discard;
923 new->output = dst_discard;
924
925 if (dst_metrics_read_only(&ort->dst))
926 new->_metrics = ort->dst._metrics;
927 else
928 dst_copy_metrics(new, &ort->dst);
929 rt->rt6i_idev = ort->rt6i_idev;
930 if (rt->rt6i_idev)
931 in6_dev_hold(rt->rt6i_idev);
932 rt->rt6i_expires = 0;
933
934 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
935 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
936 rt->rt6i_metric = 0;
937
938 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
939#ifdef CONFIG_IPV6_SUBTREES
940 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
941#endif
942
943 dst_free(new);
944 }
945
946 dst_release(dst_orig);
947 return new ? new : ERR_PTR(-ENOMEM);
948}
949
950/*
951 * Destination cache support functions
952 */
953
954static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
955{
956 struct rt6_info *rt;
957
958 rt = (struct rt6_info *) dst;
959
960 if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
961 if (rt->rt6i_peer_genid != rt6_peer_genid()) {
962 if (!rt->rt6i_peer)
963 rt6_bind_peer(rt, 0);
964 rt->rt6i_peer_genid = rt6_peer_genid();
965 }
966 return dst;
967 }
968 return NULL;
969}
970
971static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
972{
973 struct rt6_info *rt = (struct rt6_info *) dst;
974
975 if (rt) {
976 if (rt->rt6i_flags & RTF_CACHE) {
977 if (rt6_check_expired(rt)) {
978 ip6_del_rt(rt);
979 dst = NULL;
980 }
981 } else {
982 dst_release(dst);
983 dst = NULL;
984 }
985 }
986 return dst;
987}
988
989static void ip6_link_failure(struct sk_buff *skb)
990{
991 struct rt6_info *rt;
992
993 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
994
995 rt = (struct rt6_info *) skb_dst(skb);
996 if (rt) {
997 if (rt->rt6i_flags&RTF_CACHE) {
998 dst_set_expires(&rt->dst, 0);
999 rt->rt6i_flags |= RTF_EXPIRES;
1000 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
1001 rt->rt6i_node->fn_sernum = -1;
1002 }
1003}
1004
1005static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
1006{
1007 struct rt6_info *rt6 = (struct rt6_info*)dst;
1008
1009 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
1010 rt6->rt6i_flags |= RTF_MODIFIED;
1011 if (mtu < IPV6_MIN_MTU) {
1012 u32 features = dst_metric(dst, RTAX_FEATURES);
1013 mtu = IPV6_MIN_MTU;
1014 features |= RTAX_FEATURE_ALLFRAG;
1015 dst_metric_set(dst, RTAX_FEATURES, features);
1016 }
1017 dst_metric_set(dst, RTAX_MTU, mtu);
1018 }
1019}
1020
1021static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1022{
1023 struct net_device *dev = dst->dev;
1024 unsigned int mtu = dst_mtu(dst);
1025 struct net *net = dev_net(dev);
1026
1027 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1028
1029 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1030 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1031
1032 /*
1033 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1034 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1035 * IPV6_MAXPLEN is also valid and means: "any MSS,
1036 * rely only on pmtu discovery"
1037 */
1038 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1039 mtu = IPV6_MAXPLEN;
1040 return mtu;
1041}
1042
1043static unsigned int ip6_default_mtu(const struct dst_entry *dst)
1044{
1045 unsigned int mtu = IPV6_MIN_MTU;
1046 struct inet6_dev *idev;
1047
1048 rcu_read_lock();
1049 idev = __in6_dev_get(dst->dev);
1050 if (idev)
1051 mtu = idev->cnf.mtu6;
1052 rcu_read_unlock();
1053
1054 return mtu;
1055}
1056
1057static struct dst_entry *icmp6_dst_gc_list;
1058static DEFINE_SPINLOCK(icmp6_dst_lock);
1059
1060struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1061 struct neighbour *neigh,
1062 const struct in6_addr *addr)
1063{
1064 struct rt6_info *rt;
1065 struct inet6_dev *idev = in6_dev_get(dev);
1066 struct net *net = dev_net(dev);
1067
1068 if (unlikely(idev == NULL))
1069 return NULL;
1070
1071 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops, dev, 0);
1072 if (unlikely(rt == NULL)) {
1073 in6_dev_put(idev);
1074 goto out;
1075 }
1076
1077 if (neigh)
1078 neigh_hold(neigh);
1079 else {
1080 neigh = ndisc_get_neigh(dev, addr);
1081 if (IS_ERR(neigh))
1082 neigh = NULL;
1083 }
1084
1085 rt->dst.flags |= DST_HOST;
1086 rt->dst.output = ip6_output;
1087 dst_set_neighbour(&rt->dst, neigh);
1088 atomic_set(&rt->dst.__refcnt, 1);
1089 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
1090
1091 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1092 rt->rt6i_dst.plen = 128;
1093 rt->rt6i_idev = idev;
1094
1095 spin_lock_bh(&icmp6_dst_lock);
1096 rt->dst.next = icmp6_dst_gc_list;
1097 icmp6_dst_gc_list = &rt->dst;
1098 spin_unlock_bh(&icmp6_dst_lock);
1099
1100 fib6_force_start_gc(net);
1101
1102out:
1103 return &rt->dst;
1104}
1105
1106int icmp6_dst_gc(void)
1107{
1108 struct dst_entry *dst, **pprev;
1109 int more = 0;
1110
1111 spin_lock_bh(&icmp6_dst_lock);
1112 pprev = &icmp6_dst_gc_list;
1113
1114 while ((dst = *pprev) != NULL) {
1115 if (!atomic_read(&dst->__refcnt)) {
1116 *pprev = dst->next;
1117 dst_free(dst);
1118 } else {
1119 pprev = &dst->next;
1120 ++more;
1121 }
1122 }
1123
1124 spin_unlock_bh(&icmp6_dst_lock);
1125
1126 return more;
1127}
1128
1129static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1130 void *arg)
1131{
1132 struct dst_entry *dst, **pprev;
1133
1134 spin_lock_bh(&icmp6_dst_lock);
1135 pprev = &icmp6_dst_gc_list;
1136 while ((dst = *pprev) != NULL) {
1137 struct rt6_info *rt = (struct rt6_info *) dst;
1138 if (func(rt, arg)) {
1139 *pprev = dst->next;
1140 dst_free(dst);
1141 } else {
1142 pprev = &dst->next;
1143 }
1144 }
1145 spin_unlock_bh(&icmp6_dst_lock);
1146}
1147
1148static int ip6_dst_gc(struct dst_ops *ops)
1149{
1150 unsigned long now = jiffies;
1151 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1152 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1153 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1154 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1155 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1156 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1157 int entries;
1158
1159 entries = dst_entries_get_fast(ops);
1160 if (time_after(rt_last_gc + rt_min_interval, now) &&
1161 entries <= rt_max_size)
1162 goto out;
1163
1164 net->ipv6.ip6_rt_gc_expire++;
1165 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
1166 net->ipv6.ip6_rt_last_gc = now;
1167 entries = dst_entries_get_slow(ops);
1168 if (entries < ops->gc_thresh)
1169 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1170out:
1171 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1172 return entries > rt_max_size;
1173}
1174
1175/* Clean host part of a prefix. Not necessary in radix tree,
1176 but results in cleaner routing tables.
1177
1178 Remove it only when all the things will work!
1179 */
1180
1181int ip6_dst_hoplimit(struct dst_entry *dst)
1182{
1183 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
1184 if (hoplimit == 0) {
1185 struct net_device *dev = dst->dev;
1186 struct inet6_dev *idev;
1187
1188 rcu_read_lock();
1189 idev = __in6_dev_get(dev);
1190 if (idev)
1191 hoplimit = idev->cnf.hop_limit;
1192 else
1193 hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1194 rcu_read_unlock();
1195 }
1196 return hoplimit;
1197}
1198EXPORT_SYMBOL(ip6_dst_hoplimit);
1199
1200/*
1201 *
1202 */
1203
1204int ip6_route_add(struct fib6_config *cfg)
1205{
1206 int err;
1207 struct net *net = cfg->fc_nlinfo.nl_net;
1208 struct rt6_info *rt = NULL;
1209 struct net_device *dev = NULL;
1210 struct inet6_dev *idev = NULL;
1211 struct fib6_table *table;
1212 int addr_type;
1213
1214 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1215 return -EINVAL;
1216#ifndef CONFIG_IPV6_SUBTREES
1217 if (cfg->fc_src_len)
1218 return -EINVAL;
1219#endif
1220 if (cfg->fc_ifindex) {
1221 err = -ENODEV;
1222 dev = dev_get_by_index(net, cfg->fc_ifindex);
1223 if (!dev)
1224 goto out;
1225 idev = in6_dev_get(dev);
1226 if (!idev)
1227 goto out;
1228 }
1229
1230 if (cfg->fc_metric == 0)
1231 cfg->fc_metric = IP6_RT_PRIO_USER;
1232
1233 table = fib6_new_table(net, cfg->fc_table);
1234 if (table == NULL) {
1235 err = -ENOBUFS;
1236 goto out;
1237 }
1238
1239 rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops, NULL, DST_NOCOUNT);
1240
1241 if (rt == NULL) {
1242 err = -ENOMEM;
1243 goto out;
1244 }
1245
1246 rt->dst.obsolete = -1;
1247 rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ?
1248 jiffies + clock_t_to_jiffies(cfg->fc_expires) :
1249 0;
1250
1251 if (cfg->fc_protocol == RTPROT_UNSPEC)
1252 cfg->fc_protocol = RTPROT_BOOT;
1253 rt->rt6i_protocol = cfg->fc_protocol;
1254
1255 addr_type = ipv6_addr_type(&cfg->fc_dst);
1256
1257 if (addr_type & IPV6_ADDR_MULTICAST)
1258 rt->dst.input = ip6_mc_input;
1259 else if (cfg->fc_flags & RTF_LOCAL)
1260 rt->dst.input = ip6_input;
1261 else
1262 rt->dst.input = ip6_forward;
1263
1264 rt->dst.output = ip6_output;
1265
1266 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1267 rt->rt6i_dst.plen = cfg->fc_dst_len;
1268 if (rt->rt6i_dst.plen == 128)
1269 rt->dst.flags |= DST_HOST;
1270
1271 if (!(rt->dst.flags & DST_HOST) && cfg->fc_mx) {
1272 u32 *metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1273 if (!metrics) {
1274 err = -ENOMEM;
1275 goto out;
1276 }
1277 dst_init_metrics(&rt->dst, metrics, 0);
1278 }
1279#ifdef CONFIG_IPV6_SUBTREES
1280 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1281 rt->rt6i_src.plen = cfg->fc_src_len;
1282#endif
1283
1284 rt->rt6i_metric = cfg->fc_metric;
1285
1286 /* We cannot add true routes via loopback here,
1287 they would result in kernel looping; promote them to reject routes
1288 */
1289 if ((cfg->fc_flags & RTF_REJECT) ||
1290 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK)
1291 && !(cfg->fc_flags&RTF_LOCAL))) {
1292 /* hold loopback dev/idev if we haven't done so. */
1293 if (dev != net->loopback_dev) {
1294 if (dev) {
1295 dev_put(dev);
1296 in6_dev_put(idev);
1297 }
1298 dev = net->loopback_dev;
1299 dev_hold(dev);
1300 idev = in6_dev_get(dev);
1301 if (!idev) {
1302 err = -ENODEV;
1303 goto out;
1304 }
1305 }
1306 rt->dst.output = ip6_pkt_discard_out;
1307 rt->dst.input = ip6_pkt_discard;
1308 rt->dst.error = -ENETUNREACH;
1309 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1310 goto install_route;
1311 }
1312
1313 if (cfg->fc_flags & RTF_GATEWAY) {
1314 const struct in6_addr *gw_addr;
1315 int gwa_type;
1316
1317 gw_addr = &cfg->fc_gateway;
1318 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1319 gwa_type = ipv6_addr_type(gw_addr);
1320
1321 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1322 struct rt6_info *grt;
1323
1324 /* IPv6 strictly inhibits using not link-local
1325 addresses as nexthop address.
1326 Otherwise, router will not able to send redirects.
1327 It is very good, but in some (rare!) circumstances
1328 (SIT, PtP, NBMA NOARP links) it is handy to allow
1329 some exceptions. --ANK
1330 */
1331 err = -EINVAL;
1332 if (!(gwa_type&IPV6_ADDR_UNICAST))
1333 goto out;
1334
1335 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1336
1337 err = -EHOSTUNREACH;
1338 if (grt == NULL)
1339 goto out;
1340 if (dev) {
1341 if (dev != grt->rt6i_dev) {
1342 dst_release(&grt->dst);
1343 goto out;
1344 }
1345 } else {
1346 dev = grt->rt6i_dev;
1347 idev = grt->rt6i_idev;
1348 dev_hold(dev);
1349 in6_dev_hold(grt->rt6i_idev);
1350 }
1351 if (!(grt->rt6i_flags&RTF_GATEWAY))
1352 err = 0;
1353 dst_release(&grt->dst);
1354
1355 if (err)
1356 goto out;
1357 }
1358 err = -EINVAL;
1359 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1360 goto out;
1361 }
1362
1363 err = -ENODEV;
1364 if (dev == NULL)
1365 goto out;
1366
1367 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1368 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1369 err = -EINVAL;
1370 goto out;
1371 }
1372 ipv6_addr_copy(&rt->rt6i_prefsrc.addr, &cfg->fc_prefsrc);
1373 rt->rt6i_prefsrc.plen = 128;
1374 } else
1375 rt->rt6i_prefsrc.plen = 0;
1376
1377 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1378 struct neighbour *n = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1379 if (IS_ERR(n)) {
1380 err = PTR_ERR(n);
1381 goto out;
1382 }
1383 dst_set_neighbour(&rt->dst, n);
1384 }
1385
1386 rt->rt6i_flags = cfg->fc_flags;
1387
1388install_route:
1389 if (cfg->fc_mx) {
1390 struct nlattr *nla;
1391 int remaining;
1392
1393 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1394 int type = nla_type(nla);
1395
1396 if (type) {
1397 if (type > RTAX_MAX) {
1398 err = -EINVAL;
1399 goto out;
1400 }
1401
1402 dst_metric_set(&rt->dst, type, nla_get_u32(nla));
1403 }
1404 }
1405 }
1406
1407 rt->dst.dev = dev;
1408 rt->rt6i_idev = idev;
1409 rt->rt6i_table = table;
1410
1411 cfg->fc_nlinfo.nl_net = dev_net(dev);
1412
1413 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1414
1415out:
1416 if (dev)
1417 dev_put(dev);
1418 if (idev)
1419 in6_dev_put(idev);
1420 if (rt)
1421 dst_free(&rt->dst);
1422 return err;
1423}
1424
1425static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1426{
1427 int err;
1428 struct fib6_table *table;
1429 struct net *net = dev_net(rt->rt6i_dev);
1430
1431 if (rt == net->ipv6.ip6_null_entry)
1432 return -ENOENT;
1433
1434 table = rt->rt6i_table;
1435 write_lock_bh(&table->tb6_lock);
1436
1437 err = fib6_del(rt, info);
1438 dst_release(&rt->dst);
1439
1440 write_unlock_bh(&table->tb6_lock);
1441
1442 return err;
1443}
1444
1445int ip6_del_rt(struct rt6_info *rt)
1446{
1447 struct nl_info info = {
1448 .nl_net = dev_net(rt->rt6i_dev),
1449 };
1450 return __ip6_del_rt(rt, &info);
1451}
1452
1453static int ip6_route_del(struct fib6_config *cfg)
1454{
1455 struct fib6_table *table;
1456 struct fib6_node *fn;
1457 struct rt6_info *rt;
1458 int err = -ESRCH;
1459
1460 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1461 if (table == NULL)
1462 return err;
1463
1464 read_lock_bh(&table->tb6_lock);
1465
1466 fn = fib6_locate(&table->tb6_root,
1467 &cfg->fc_dst, cfg->fc_dst_len,
1468 &cfg->fc_src, cfg->fc_src_len);
1469
1470 if (fn) {
1471 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1472 if (cfg->fc_ifindex &&
1473 (rt->rt6i_dev == NULL ||
1474 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1475 continue;
1476 if (cfg->fc_flags & RTF_GATEWAY &&
1477 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1478 continue;
1479 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1480 continue;
1481 dst_hold(&rt->dst);
1482 read_unlock_bh(&table->tb6_lock);
1483
1484 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1485 }
1486 }
1487 read_unlock_bh(&table->tb6_lock);
1488
1489 return err;
1490}
1491
1492/*
1493 * Handle redirects
1494 */
1495struct ip6rd_flowi {
1496 struct flowi6 fl6;
1497 struct in6_addr gateway;
1498};
1499
1500static struct rt6_info *__ip6_route_redirect(struct net *net,
1501 struct fib6_table *table,
1502 struct flowi6 *fl6,
1503 int flags)
1504{
1505 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1506 struct rt6_info *rt;
1507 struct fib6_node *fn;
1508
1509 /*
1510 * Get the "current" route for this destination and
1511 * check if the redirect has come from approriate router.
1512 *
1513 * RFC 2461 specifies that redirects should only be
1514 * accepted if they come from the nexthop to the target.
1515 * Due to the way the routes are chosen, this notion
1516 * is a bit fuzzy and one might need to check all possible
1517 * routes.
1518 */
1519
1520 read_lock_bh(&table->tb6_lock);
1521 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1522restart:
1523 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1524 /*
1525 * Current route is on-link; redirect is always invalid.
1526 *
1527 * Seems, previous statement is not true. It could
1528 * be node, which looks for us as on-link (f.e. proxy ndisc)
1529 * But then router serving it might decide, that we should
1530 * know truth 8)8) --ANK (980726).
1531 */
1532 if (rt6_check_expired(rt))
1533 continue;
1534 if (!(rt->rt6i_flags & RTF_GATEWAY))
1535 continue;
1536 if (fl6->flowi6_oif != rt->rt6i_dev->ifindex)
1537 continue;
1538 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1539 continue;
1540 break;
1541 }
1542
1543 if (!rt)
1544 rt = net->ipv6.ip6_null_entry;
1545 BACKTRACK(net, &fl6->saddr);
1546out:
1547 dst_hold(&rt->dst);
1548
1549 read_unlock_bh(&table->tb6_lock);
1550
1551 return rt;
1552};
1553
1554static struct rt6_info *ip6_route_redirect(const struct in6_addr *dest,
1555 const struct in6_addr *src,
1556 const struct in6_addr *gateway,
1557 struct net_device *dev)
1558{
1559 int flags = RT6_LOOKUP_F_HAS_SADDR;
1560 struct net *net = dev_net(dev);
1561 struct ip6rd_flowi rdfl = {
1562 .fl6 = {
1563 .flowi6_oif = dev->ifindex,
1564 .daddr = *dest,
1565 .saddr = *src,
1566 },
1567 };
1568
1569 ipv6_addr_copy(&rdfl.gateway, gateway);
1570
1571 if (rt6_need_strict(dest))
1572 flags |= RT6_LOOKUP_F_IFACE;
1573
1574 return (struct rt6_info *)fib6_rule_lookup(net, &rdfl.fl6,
1575 flags, __ip6_route_redirect);
1576}
1577
1578void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src,
1579 const struct in6_addr *saddr,
1580 struct neighbour *neigh, u8 *lladdr, int on_link)
1581{
1582 struct rt6_info *rt, *nrt = NULL;
1583 struct netevent_redirect netevent;
1584 struct net *net = dev_net(neigh->dev);
1585
1586 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1587
1588 if (rt == net->ipv6.ip6_null_entry) {
1589 if (net_ratelimit())
1590 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1591 "for redirect target\n");
1592 goto out;
1593 }
1594
1595 /*
1596 * We have finally decided to accept it.
1597 */
1598
1599 neigh_update(neigh, lladdr, NUD_STALE,
1600 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1601 NEIGH_UPDATE_F_OVERRIDE|
1602 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1603 NEIGH_UPDATE_F_ISROUTER))
1604 );
1605
1606 /*
1607 * Redirect received -> path was valid.
1608 * Look, redirects are sent only in response to data packets,
1609 * so that this nexthop apparently is reachable. --ANK
1610 */
1611 dst_confirm(&rt->dst);
1612
1613 /* Duplicate redirect: silently ignore. */
1614 if (neigh == dst_get_neighbour_raw(&rt->dst))
1615 goto out;
1616
1617 nrt = ip6_rt_copy(rt, dest);
1618 if (nrt == NULL)
1619 goto out;
1620
1621 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1622 if (on_link)
1623 nrt->rt6i_flags &= ~RTF_GATEWAY;
1624
1625 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1626 dst_set_neighbour(&nrt->dst, neigh_clone(neigh));
1627
1628 if (ip6_ins_rt(nrt))
1629 goto out;
1630
1631 netevent.old = &rt->dst;
1632 netevent.new = &nrt->dst;
1633 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1634
1635 if (rt->rt6i_flags&RTF_CACHE) {
1636 ip6_del_rt(rt);
1637 return;
1638 }
1639
1640out:
1641 dst_release(&rt->dst);
1642}
1643
1644/*
1645 * Handle ICMP "packet too big" messages
1646 * i.e. Path MTU discovery
1647 */
1648
1649static void rt6_do_pmtu_disc(const struct in6_addr *daddr, const struct in6_addr *saddr,
1650 struct net *net, u32 pmtu, int ifindex)
1651{
1652 struct rt6_info *rt, *nrt;
1653 int allfrag = 0;
1654again:
1655 rt = rt6_lookup(net, daddr, saddr, ifindex, 0);
1656 if (rt == NULL)
1657 return;
1658
1659 if (rt6_check_expired(rt)) {
1660 ip6_del_rt(rt);
1661 goto again;
1662 }
1663
1664 if (pmtu >= dst_mtu(&rt->dst))
1665 goto out;
1666
1667 if (pmtu < IPV6_MIN_MTU) {
1668 /*
1669 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1670 * MTU (1280) and a fragment header should always be included
1671 * after a node receiving Too Big message reporting PMTU is
1672 * less than the IPv6 Minimum Link MTU.
1673 */
1674 pmtu = IPV6_MIN_MTU;
1675 allfrag = 1;
1676 }
1677
1678 /* New mtu received -> path was valid.
1679 They are sent only in response to data packets,
1680 so that this nexthop apparently is reachable. --ANK
1681 */
1682 dst_confirm(&rt->dst);
1683
1684 /* Host route. If it is static, it would be better
1685 not to override it, but add new one, so that
1686 when cache entry will expire old pmtu
1687 would return automatically.
1688 */
1689 if (rt->rt6i_flags & RTF_CACHE) {
1690 dst_metric_set(&rt->dst, RTAX_MTU, pmtu);
1691 if (allfrag) {
1692 u32 features = dst_metric(&rt->dst, RTAX_FEATURES);
1693 features |= RTAX_FEATURE_ALLFRAG;
1694 dst_metric_set(&rt->dst, RTAX_FEATURES, features);
1695 }
1696 dst_set_expires(&rt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1697 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1698 goto out;
1699 }
1700
1701 /* Network route.
1702 Two cases are possible:
1703 1. It is connected route. Action: COW
1704 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1705 */
1706 if (!dst_get_neighbour_raw(&rt->dst) && !(rt->rt6i_flags & RTF_NONEXTHOP))
1707 nrt = rt6_alloc_cow(rt, daddr, saddr);
1708 else
1709 nrt = rt6_alloc_clone(rt, daddr);
1710
1711 if (nrt) {
1712 dst_metric_set(&nrt->dst, RTAX_MTU, pmtu);
1713 if (allfrag) {
1714 u32 features = dst_metric(&nrt->dst, RTAX_FEATURES);
1715 features |= RTAX_FEATURE_ALLFRAG;
1716 dst_metric_set(&nrt->dst, RTAX_FEATURES, features);
1717 }
1718
1719 /* According to RFC 1981, detecting PMTU increase shouldn't be
1720 * happened within 5 mins, the recommended timer is 10 mins.
1721 * Here this route expiration time is set to ip6_rt_mtu_expires
1722 * which is 10 mins. After 10 mins the decreased pmtu is expired
1723 * and detecting PMTU increase will be automatically happened.
1724 */
1725 dst_set_expires(&nrt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1726 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1727
1728 ip6_ins_rt(nrt);
1729 }
1730out:
1731 dst_release(&rt->dst);
1732}
1733
1734void rt6_pmtu_discovery(const struct in6_addr *daddr, const struct in6_addr *saddr,
1735 struct net_device *dev, u32 pmtu)
1736{
1737 struct net *net = dev_net(dev);
1738
1739 /*
1740 * RFC 1981 states that a node "MUST reduce the size of the packets it
1741 * is sending along the path" that caused the Packet Too Big message.
1742 * Since it's not possible in the general case to determine which
1743 * interface was used to send the original packet, we update the MTU
1744 * on the interface that will be used to send future packets. We also
1745 * update the MTU on the interface that received the Packet Too Big in
1746 * case the original packet was forced out that interface with
1747 * SO_BINDTODEVICE or similar. This is the next best thing to the
1748 * correct behaviour, which would be to update the MTU on all
1749 * interfaces.
1750 */
1751 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, 0);
1752 rt6_do_pmtu_disc(daddr, saddr, net, pmtu, dev->ifindex);
1753}
1754
1755/*
1756 * Misc support functions
1757 */
1758
1759static struct rt6_info *ip6_rt_copy(const struct rt6_info *ort,
1760 const struct in6_addr *dest)
1761{
1762 struct net *net = dev_net(ort->rt6i_dev);
1763 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,
1764 ort->dst.dev, 0);
1765
1766 if (rt) {
1767 rt->dst.input = ort->dst.input;
1768 rt->dst.output = ort->dst.output;
1769 rt->dst.flags |= DST_HOST;
1770
1771 ipv6_addr_copy(&rt->rt6i_dst.addr, dest);
1772 rt->rt6i_dst.plen = 128;
1773 dst_copy_metrics(&rt->dst, &ort->dst);
1774 rt->dst.error = ort->dst.error;
1775 rt->rt6i_idev = ort->rt6i_idev;
1776 if (rt->rt6i_idev)
1777 in6_dev_hold(rt->rt6i_idev);
1778 rt->dst.lastuse = jiffies;
1779 rt->rt6i_expires = 0;
1780
1781 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1782 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1783 rt->rt6i_metric = 0;
1784
1785#ifdef CONFIG_IPV6_SUBTREES
1786 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1787#endif
1788 memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key));
1789 rt->rt6i_table = ort->rt6i_table;
1790 }
1791 return rt;
1792}
1793
1794#ifdef CONFIG_IPV6_ROUTE_INFO
1795static struct rt6_info *rt6_get_route_info(struct net *net,
1796 const struct in6_addr *prefix, int prefixlen,
1797 const struct in6_addr *gwaddr, int ifindex)
1798{
1799 struct fib6_node *fn;
1800 struct rt6_info *rt = NULL;
1801 struct fib6_table *table;
1802
1803 table = fib6_get_table(net, RT6_TABLE_INFO);
1804 if (table == NULL)
1805 return NULL;
1806
1807 write_lock_bh(&table->tb6_lock);
1808 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1809 if (!fn)
1810 goto out;
1811
1812 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1813 if (rt->rt6i_dev->ifindex != ifindex)
1814 continue;
1815 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1816 continue;
1817 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1818 continue;
1819 dst_hold(&rt->dst);
1820 break;
1821 }
1822out:
1823 write_unlock_bh(&table->tb6_lock);
1824 return rt;
1825}
1826
1827static struct rt6_info *rt6_add_route_info(struct net *net,
1828 const struct in6_addr *prefix, int prefixlen,
1829 const struct in6_addr *gwaddr, int ifindex,
1830 unsigned pref)
1831{
1832 struct fib6_config cfg = {
1833 .fc_table = RT6_TABLE_INFO,
1834 .fc_metric = IP6_RT_PRIO_USER,
1835 .fc_ifindex = ifindex,
1836 .fc_dst_len = prefixlen,
1837 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1838 RTF_UP | RTF_PREF(pref),
1839 .fc_nlinfo.pid = 0,
1840 .fc_nlinfo.nlh = NULL,
1841 .fc_nlinfo.nl_net = net,
1842 };
1843
1844 ipv6_addr_copy(&cfg.fc_dst, prefix);
1845 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1846
1847 /* We should treat it as a default route if prefix length is 0. */
1848 if (!prefixlen)
1849 cfg.fc_flags |= RTF_DEFAULT;
1850
1851 ip6_route_add(&cfg);
1852
1853 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1854}
1855#endif
1856
1857struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
1858{
1859 struct rt6_info *rt;
1860 struct fib6_table *table;
1861
1862 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1863 if (table == NULL)
1864 return NULL;
1865
1866 write_lock_bh(&table->tb6_lock);
1867 for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
1868 if (dev == rt->rt6i_dev &&
1869 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1870 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1871 break;
1872 }
1873 if (rt)
1874 dst_hold(&rt->dst);
1875 write_unlock_bh(&table->tb6_lock);
1876 return rt;
1877}
1878
1879struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
1880 struct net_device *dev,
1881 unsigned int pref)
1882{
1883 struct fib6_config cfg = {
1884 .fc_table = RT6_TABLE_DFLT,
1885 .fc_metric = IP6_RT_PRIO_USER,
1886 .fc_ifindex = dev->ifindex,
1887 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1888 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1889 .fc_nlinfo.pid = 0,
1890 .fc_nlinfo.nlh = NULL,
1891 .fc_nlinfo.nl_net = dev_net(dev),
1892 };
1893
1894 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1895
1896 ip6_route_add(&cfg);
1897
1898 return rt6_get_dflt_router(gwaddr, dev);
1899}
1900
1901void rt6_purge_dflt_routers(struct net *net)
1902{
1903 struct rt6_info *rt;
1904 struct fib6_table *table;
1905
1906 /* NOTE: Keep consistent with rt6_get_dflt_router */
1907 table = fib6_get_table(net, RT6_TABLE_DFLT);
1908 if (table == NULL)
1909 return;
1910
1911restart:
1912 read_lock_bh(&table->tb6_lock);
1913 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
1914 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1915 dst_hold(&rt->dst);
1916 read_unlock_bh(&table->tb6_lock);
1917 ip6_del_rt(rt);
1918 goto restart;
1919 }
1920 }
1921 read_unlock_bh(&table->tb6_lock);
1922}
1923
1924static void rtmsg_to_fib6_config(struct net *net,
1925 struct in6_rtmsg *rtmsg,
1926 struct fib6_config *cfg)
1927{
1928 memset(cfg, 0, sizeof(*cfg));
1929
1930 cfg->fc_table = RT6_TABLE_MAIN;
1931 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1932 cfg->fc_metric = rtmsg->rtmsg_metric;
1933 cfg->fc_expires = rtmsg->rtmsg_info;
1934 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1935 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1936 cfg->fc_flags = rtmsg->rtmsg_flags;
1937
1938 cfg->fc_nlinfo.nl_net = net;
1939
1940 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1941 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1942 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1943}
1944
1945int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
1946{
1947 struct fib6_config cfg;
1948 struct in6_rtmsg rtmsg;
1949 int err;
1950
1951 switch(cmd) {
1952 case SIOCADDRT: /* Add a route */
1953 case SIOCDELRT: /* Delete a route */
1954 if (!capable(CAP_NET_ADMIN))
1955 return -EPERM;
1956 err = copy_from_user(&rtmsg, arg,
1957 sizeof(struct in6_rtmsg));
1958 if (err)
1959 return -EFAULT;
1960
1961 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1962
1963 rtnl_lock();
1964 switch (cmd) {
1965 case SIOCADDRT:
1966 err = ip6_route_add(&cfg);
1967 break;
1968 case SIOCDELRT:
1969 err = ip6_route_del(&cfg);
1970 break;
1971 default:
1972 err = -EINVAL;
1973 }
1974 rtnl_unlock();
1975
1976 return err;
1977 }
1978
1979 return -EINVAL;
1980}
1981
1982/*
1983 * Drop the packet on the floor
1984 */
1985
1986static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
1987{
1988 int type;
1989 struct dst_entry *dst = skb_dst(skb);
1990 switch (ipstats_mib_noroutes) {
1991 case IPSTATS_MIB_INNOROUTES:
1992 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1993 if (type == IPV6_ADDR_ANY) {
1994 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
1995 IPSTATS_MIB_INADDRERRORS);
1996 break;
1997 }
1998 /* FALLTHROUGH */
1999 case IPSTATS_MIB_OUTNOROUTES:
2000 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2001 ipstats_mib_noroutes);
2002 break;
2003 }
2004 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2005 kfree_skb(skb);
2006 return 0;
2007}
2008
2009static int ip6_pkt_discard(struct sk_buff *skb)
2010{
2011 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2012}
2013
2014static int ip6_pkt_discard_out(struct sk_buff *skb)
2015{
2016 skb->dev = skb_dst(skb)->dev;
2017 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2018}
2019
2020#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2021
2022static int ip6_pkt_prohibit(struct sk_buff *skb)
2023{
2024 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2025}
2026
2027static int ip6_pkt_prohibit_out(struct sk_buff *skb)
2028{
2029 skb->dev = skb_dst(skb)->dev;
2030 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2031}
2032
2033#endif
2034
2035/*
2036 * Allocate a dst for local (unicast / anycast) address.
2037 */
2038
2039struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2040 const struct in6_addr *addr,
2041 int anycast)
2042{
2043 struct net *net = dev_net(idev->dev);
2044 struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops,
2045 net->loopback_dev, 0);
2046 struct neighbour *neigh;
2047
2048 if (rt == NULL) {
2049 if (net_ratelimit())
2050 pr_warning("IPv6: Maximum number of routes reached,"
2051 " consider increasing route/max_size.\n");
2052 return ERR_PTR(-ENOMEM);
2053 }
2054
2055 in6_dev_hold(idev);
2056
2057 rt->dst.flags |= DST_HOST;
2058 rt->dst.input = ip6_input;
2059 rt->dst.output = ip6_output;
2060 rt->rt6i_idev = idev;
2061 rt->dst.obsolete = -1;
2062
2063 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2064 if (anycast)
2065 rt->rt6i_flags |= RTF_ANYCAST;
2066 else
2067 rt->rt6i_flags |= RTF_LOCAL;
2068 neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
2069 if (IS_ERR(neigh)) {
2070 dst_free(&rt->dst);
2071
2072 return ERR_CAST(neigh);
2073 }
2074 dst_set_neighbour(&rt->dst, neigh);
2075
2076 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
2077 rt->rt6i_dst.plen = 128;
2078 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2079
2080 atomic_set(&rt->dst.__refcnt, 1);
2081
2082 return rt;
2083}
2084
2085int ip6_route_get_saddr(struct net *net,
2086 struct rt6_info *rt,
2087 const struct in6_addr *daddr,
2088 unsigned int prefs,
2089 struct in6_addr *saddr)
2090{
2091 struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt);
2092 int err = 0;
2093 if (rt->rt6i_prefsrc.plen)
2094 ipv6_addr_copy(saddr, &rt->rt6i_prefsrc.addr);
2095 else
2096 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2097 daddr, prefs, saddr);
2098 return err;
2099}
2100
2101/* remove deleted ip from prefsrc entries */
2102struct arg_dev_net_ip {
2103 struct net_device *dev;
2104 struct net *net;
2105 struct in6_addr *addr;
2106};
2107
2108static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2109{
2110 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2111 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2112 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2113
2114 if (((void *)rt->rt6i_dev == dev || dev == NULL) &&
2115 rt != net->ipv6.ip6_null_entry &&
2116 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2117 /* remove prefsrc entry */
2118 rt->rt6i_prefsrc.plen = 0;
2119 }
2120 return 0;
2121}
2122
2123void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2124{
2125 struct net *net = dev_net(ifp->idev->dev);
2126 struct arg_dev_net_ip adni = {
2127 .dev = ifp->idev->dev,
2128 .net = net,
2129 .addr = &ifp->addr,
2130 };
2131 fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni);
2132}
2133
2134struct arg_dev_net {
2135 struct net_device *dev;
2136 struct net *net;
2137};
2138
2139static int fib6_ifdown(struct rt6_info *rt, void *arg)
2140{
2141 const struct arg_dev_net *adn = arg;
2142 const struct net_device *dev = adn->dev;
2143
2144 if ((rt->rt6i_dev == dev || dev == NULL) &&
2145 rt != adn->net->ipv6.ip6_null_entry) {
2146 RT6_TRACE("deleted by ifdown %p\n", rt);
2147 return -1;
2148 }
2149 return 0;
2150}
2151
2152void rt6_ifdown(struct net *net, struct net_device *dev)
2153{
2154 struct arg_dev_net adn = {
2155 .dev = dev,
2156 .net = net,
2157 };
2158
2159 fib6_clean_all(net, fib6_ifdown, 0, &adn);
2160 icmp6_clean_all(fib6_ifdown, &adn);
2161}
2162
2163struct rt6_mtu_change_arg
2164{
2165 struct net_device *dev;
2166 unsigned mtu;
2167};
2168
2169static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2170{
2171 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2172 struct inet6_dev *idev;
2173
2174 /* In IPv6 pmtu discovery is not optional,
2175 so that RTAX_MTU lock cannot disable it.
2176 We still use this lock to block changes
2177 caused by addrconf/ndisc.
2178 */
2179
2180 idev = __in6_dev_get(arg->dev);
2181 if (idev == NULL)
2182 return 0;
2183
2184 /* For administrative MTU increase, there is no way to discover
2185 IPv6 PMTU increase, so PMTU increase should be updated here.
2186 Since RFC 1981 doesn't include administrative MTU increase
2187 update PMTU increase is a MUST. (i.e. jumbo frame)
2188 */
2189 /*
2190 If new MTU is less than route PMTU, this new MTU will be the
2191 lowest MTU in the path, update the route PMTU to reflect PMTU
2192 decreases; if new MTU is greater than route PMTU, and the
2193 old MTU is the lowest MTU in the path, update the route PMTU
2194 to reflect the increase. In this case if the other nodes' MTU
2195 also have the lowest MTU, TOO BIG MESSAGE will be lead to
2196 PMTU discouvery.
2197 */
2198 if (rt->rt6i_dev == arg->dev &&
2199 !dst_metric_locked(&rt->dst, RTAX_MTU) &&
2200 (dst_mtu(&rt->dst) >= arg->mtu ||
2201 (dst_mtu(&rt->dst) < arg->mtu &&
2202 dst_mtu(&rt->dst) == idev->cnf.mtu6))) {
2203 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2204 }
2205 return 0;
2206}
2207
2208void rt6_mtu_change(struct net_device *dev, unsigned mtu)
2209{
2210 struct rt6_mtu_change_arg arg = {
2211 .dev = dev,
2212 .mtu = mtu,
2213 };
2214
2215 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
2216}
2217
2218static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2219 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2220 [RTA_OIF] = { .type = NLA_U32 },
2221 [RTA_IIF] = { .type = NLA_U32 },
2222 [RTA_PRIORITY] = { .type = NLA_U32 },
2223 [RTA_METRICS] = { .type = NLA_NESTED },
2224};
2225
2226static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2227 struct fib6_config *cfg)
2228{
2229 struct rtmsg *rtm;
2230 struct nlattr *tb[RTA_MAX+1];
2231 int err;
2232
2233 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2234 if (err < 0)
2235 goto errout;
2236
2237 err = -EINVAL;
2238 rtm = nlmsg_data(nlh);
2239 memset(cfg, 0, sizeof(*cfg));
2240
2241 cfg->fc_table = rtm->rtm_table;
2242 cfg->fc_dst_len = rtm->rtm_dst_len;
2243 cfg->fc_src_len = rtm->rtm_src_len;
2244 cfg->fc_flags = RTF_UP;
2245 cfg->fc_protocol = rtm->rtm_protocol;
2246
2247 if (rtm->rtm_type == RTN_UNREACHABLE)
2248 cfg->fc_flags |= RTF_REJECT;
2249
2250 if (rtm->rtm_type == RTN_LOCAL)
2251 cfg->fc_flags |= RTF_LOCAL;
2252
2253 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2254 cfg->fc_nlinfo.nlh = nlh;
2255 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2256
2257 if (tb[RTA_GATEWAY]) {
2258 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2259 cfg->fc_flags |= RTF_GATEWAY;
2260 }
2261
2262 if (tb[RTA_DST]) {
2263 int plen = (rtm->rtm_dst_len + 7) >> 3;
2264
2265 if (nla_len(tb[RTA_DST]) < plen)
2266 goto errout;
2267
2268 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2269 }
2270
2271 if (tb[RTA_SRC]) {
2272 int plen = (rtm->rtm_src_len + 7) >> 3;
2273
2274 if (nla_len(tb[RTA_SRC]) < plen)
2275 goto errout;
2276
2277 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2278 }
2279
2280 if (tb[RTA_PREFSRC])
2281 nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16);
2282
2283 if (tb[RTA_OIF])
2284 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2285
2286 if (tb[RTA_PRIORITY])
2287 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2288
2289 if (tb[RTA_METRICS]) {
2290 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2291 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2292 }
2293
2294 if (tb[RTA_TABLE])
2295 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2296
2297 err = 0;
2298errout:
2299 return err;
2300}
2301
2302static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2303{
2304 struct fib6_config cfg;
2305 int err;
2306
2307 err = rtm_to_fib6_config(skb, nlh, &cfg);
2308 if (err < 0)
2309 return err;
2310
2311 return ip6_route_del(&cfg);
2312}
2313
2314static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2315{
2316 struct fib6_config cfg;
2317 int err;
2318
2319 err = rtm_to_fib6_config(skb, nlh, &cfg);
2320 if (err < 0)
2321 return err;
2322
2323 return ip6_route_add(&cfg);
2324}
2325
2326static inline size_t rt6_nlmsg_size(void)
2327{
2328 return NLMSG_ALIGN(sizeof(struct rtmsg))
2329 + nla_total_size(16) /* RTA_SRC */
2330 + nla_total_size(16) /* RTA_DST */
2331 + nla_total_size(16) /* RTA_GATEWAY */
2332 + nla_total_size(16) /* RTA_PREFSRC */
2333 + nla_total_size(4) /* RTA_TABLE */
2334 + nla_total_size(4) /* RTA_IIF */
2335 + nla_total_size(4) /* RTA_OIF */
2336 + nla_total_size(4) /* RTA_PRIORITY */
2337 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2338 + nla_total_size(sizeof(struct rta_cacheinfo));
2339}
2340
2341static int rt6_fill_node(struct net *net,
2342 struct sk_buff *skb, struct rt6_info *rt,
2343 struct in6_addr *dst, struct in6_addr *src,
2344 int iif, int type, u32 pid, u32 seq,
2345 int prefix, int nowait, unsigned int flags)
2346{
2347 struct rtmsg *rtm;
2348 struct nlmsghdr *nlh;
2349 long expires;
2350 u32 table;
2351 struct neighbour *n;
2352
2353 if (prefix) { /* user wants prefix routes only */
2354 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2355 /* success since this is not a prefix route */
2356 return 1;
2357 }
2358 }
2359
2360 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2361 if (nlh == NULL)
2362 return -EMSGSIZE;
2363
2364 rtm = nlmsg_data(nlh);
2365 rtm->rtm_family = AF_INET6;
2366 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2367 rtm->rtm_src_len = rt->rt6i_src.plen;
2368 rtm->rtm_tos = 0;
2369 if (rt->rt6i_table)
2370 table = rt->rt6i_table->tb6_id;
2371 else
2372 table = RT6_TABLE_UNSPEC;
2373 rtm->rtm_table = table;
2374 NLA_PUT_U32(skb, RTA_TABLE, table);
2375 if (rt->rt6i_flags&RTF_REJECT)
2376 rtm->rtm_type = RTN_UNREACHABLE;
2377 else if (rt->rt6i_flags&RTF_LOCAL)
2378 rtm->rtm_type = RTN_LOCAL;
2379 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2380 rtm->rtm_type = RTN_LOCAL;
2381 else
2382 rtm->rtm_type = RTN_UNICAST;
2383 rtm->rtm_flags = 0;
2384 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2385 rtm->rtm_protocol = rt->rt6i_protocol;
2386 if (rt->rt6i_flags&RTF_DYNAMIC)
2387 rtm->rtm_protocol = RTPROT_REDIRECT;
2388 else if (rt->rt6i_flags & RTF_ADDRCONF)
2389 rtm->rtm_protocol = RTPROT_KERNEL;
2390 else if (rt->rt6i_flags&RTF_DEFAULT)
2391 rtm->rtm_protocol = RTPROT_RA;
2392
2393 if (rt->rt6i_flags&RTF_CACHE)
2394 rtm->rtm_flags |= RTM_F_CLONED;
2395
2396 if (dst) {
2397 NLA_PUT(skb, RTA_DST, 16, dst);
2398 rtm->rtm_dst_len = 128;
2399 } else if (rtm->rtm_dst_len)
2400 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2401#ifdef CONFIG_IPV6_SUBTREES
2402 if (src) {
2403 NLA_PUT(skb, RTA_SRC, 16, src);
2404 rtm->rtm_src_len = 128;
2405 } else if (rtm->rtm_src_len)
2406 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2407#endif
2408 if (iif) {
2409#ifdef CONFIG_IPV6_MROUTE
2410 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2411 int err = ip6mr_get_route(net, skb, rtm, nowait);
2412 if (err <= 0) {
2413 if (!nowait) {
2414 if (err == 0)
2415 return 0;
2416 goto nla_put_failure;
2417 } else {
2418 if (err == -EMSGSIZE)
2419 goto nla_put_failure;
2420 }
2421 }
2422 } else
2423#endif
2424 NLA_PUT_U32(skb, RTA_IIF, iif);
2425 } else if (dst) {
2426 struct in6_addr saddr_buf;
2427 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0)
2428 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2429 }
2430
2431 if (rt->rt6i_prefsrc.plen) {
2432 struct in6_addr saddr_buf;
2433 ipv6_addr_copy(&saddr_buf, &rt->rt6i_prefsrc.addr);
2434 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2435 }
2436
2437 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2438 goto nla_put_failure;
2439
2440 rcu_read_lock();
2441 n = dst_get_neighbour(&rt->dst);
2442 if (n)
2443 NLA_PUT(skb, RTA_GATEWAY, 16, &n->primary_key);
2444 rcu_read_unlock();
2445
2446 if (rt->dst.dev)
2447 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2448
2449 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2450
2451 if (!(rt->rt6i_flags & RTF_EXPIRES))
2452 expires = 0;
2453 else if (rt->rt6i_expires - jiffies < INT_MAX)
2454 expires = rt->rt6i_expires - jiffies;
2455 else
2456 expires = INT_MAX;
2457
2458 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0,
2459 expires, rt->dst.error) < 0)
2460 goto nla_put_failure;
2461
2462 return nlmsg_end(skb, nlh);
2463
2464nla_put_failure:
2465 nlmsg_cancel(skb, nlh);
2466 return -EMSGSIZE;
2467}
2468
2469int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2470{
2471 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2472 int prefix;
2473
2474 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2475 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2476 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2477 } else
2478 prefix = 0;
2479
2480 return rt6_fill_node(arg->net,
2481 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2482 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2483 prefix, 0, NLM_F_MULTI);
2484}
2485
2486static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2487{
2488 struct net *net = sock_net(in_skb->sk);
2489 struct nlattr *tb[RTA_MAX+1];
2490 struct rt6_info *rt;
2491 struct sk_buff *skb;
2492 struct rtmsg *rtm;
2493 struct flowi6 fl6;
2494 int err, iif = 0;
2495
2496 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2497 if (err < 0)
2498 goto errout;
2499
2500 err = -EINVAL;
2501 memset(&fl6, 0, sizeof(fl6));
2502
2503 if (tb[RTA_SRC]) {
2504 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2505 goto errout;
2506
2507 ipv6_addr_copy(&fl6.saddr, nla_data(tb[RTA_SRC]));
2508 }
2509
2510 if (tb[RTA_DST]) {
2511 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2512 goto errout;
2513
2514 ipv6_addr_copy(&fl6.daddr, nla_data(tb[RTA_DST]));
2515 }
2516
2517 if (tb[RTA_IIF])
2518 iif = nla_get_u32(tb[RTA_IIF]);
2519
2520 if (tb[RTA_OIF])
2521 fl6.flowi6_oif = nla_get_u32(tb[RTA_OIF]);
2522
2523 if (iif) {
2524 struct net_device *dev;
2525 dev = __dev_get_by_index(net, iif);
2526 if (!dev) {
2527 err = -ENODEV;
2528 goto errout;
2529 }
2530 }
2531
2532 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2533 if (skb == NULL) {
2534 err = -ENOBUFS;
2535 goto errout;
2536 }
2537
2538 /* Reserve room for dummy headers, this skb can pass
2539 through good chunk of routing engine.
2540 */
2541 skb_reset_mac_header(skb);
2542 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2543
2544 rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl6);
2545 skb_dst_set(skb, &rt->dst);
2546
2547 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
2548 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2549 nlh->nlmsg_seq, 0, 0, 0);
2550 if (err < 0) {
2551 kfree_skb(skb);
2552 goto errout;
2553 }
2554
2555 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2556errout:
2557 return err;
2558}
2559
2560void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2561{
2562 struct sk_buff *skb;
2563 struct net *net = info->nl_net;
2564 u32 seq;
2565 int err;
2566
2567 err = -ENOBUFS;
2568 seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2569
2570 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2571 if (skb == NULL)
2572 goto errout;
2573
2574 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2575 event, info->pid, seq, 0, 0, 0);
2576 if (err < 0) {
2577 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2578 WARN_ON(err == -EMSGSIZE);
2579 kfree_skb(skb);
2580 goto errout;
2581 }
2582 rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
2583 info->nlh, gfp_any());
2584 return;
2585errout:
2586 if (err < 0)
2587 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2588}
2589
2590static int ip6_route_dev_notify(struct notifier_block *this,
2591 unsigned long event, void *data)
2592{
2593 struct net_device *dev = (struct net_device *)data;
2594 struct net *net = dev_net(dev);
2595
2596 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2597 net->ipv6.ip6_null_entry->dst.dev = dev;
2598 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2599#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2600 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2601 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2602 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2603 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2604#endif
2605 }
2606
2607 return NOTIFY_OK;
2608}
2609
2610/*
2611 * /proc
2612 */
2613
2614#ifdef CONFIG_PROC_FS
2615
2616struct rt6_proc_arg
2617{
2618 char *buffer;
2619 int offset;
2620 int length;
2621 int skip;
2622 int len;
2623};
2624
2625static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2626{
2627 struct seq_file *m = p_arg;
2628 struct neighbour *n;
2629
2630 seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
2631
2632#ifdef CONFIG_IPV6_SUBTREES
2633 seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
2634#else
2635 seq_puts(m, "00000000000000000000000000000000 00 ");
2636#endif
2637 rcu_read_lock();
2638 n = dst_get_neighbour(&rt->dst);
2639 if (n) {
2640 seq_printf(m, "%pi6", n->primary_key);
2641 } else {
2642 seq_puts(m, "00000000000000000000000000000000");
2643 }
2644 rcu_read_unlock();
2645 seq_printf(m, " %08x %08x %08x %08x %8s\n",
2646 rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
2647 rt->dst.__use, rt->rt6i_flags,
2648 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2649 return 0;
2650}
2651
2652static int ipv6_route_show(struct seq_file *m, void *v)
2653{
2654 struct net *net = (struct net *)m->private;
2655 fib6_clean_all(net, rt6_info_route, 0, m);
2656 return 0;
2657}
2658
2659static int ipv6_route_open(struct inode *inode, struct file *file)
2660{
2661 return single_open_net(inode, file, ipv6_route_show);
2662}
2663
2664static const struct file_operations ipv6_route_proc_fops = {
2665 .owner = THIS_MODULE,
2666 .open = ipv6_route_open,
2667 .read = seq_read,
2668 .llseek = seq_lseek,
2669 .release = single_release_net,
2670};
2671
2672static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2673{
2674 struct net *net = (struct net *)seq->private;
2675 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2676 net->ipv6.rt6_stats->fib_nodes,
2677 net->ipv6.rt6_stats->fib_route_nodes,
2678 net->ipv6.rt6_stats->fib_rt_alloc,
2679 net->ipv6.rt6_stats->fib_rt_entries,
2680 net->ipv6.rt6_stats->fib_rt_cache,
2681 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2682 net->ipv6.rt6_stats->fib_discarded_routes);
2683
2684 return 0;
2685}
2686
2687static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2688{
2689 return single_open_net(inode, file, rt6_stats_seq_show);
2690}
2691
2692static const struct file_operations rt6_stats_seq_fops = {
2693 .owner = THIS_MODULE,
2694 .open = rt6_stats_seq_open,
2695 .read = seq_read,
2696 .llseek = seq_lseek,
2697 .release = single_release_net,
2698};
2699#endif /* CONFIG_PROC_FS */
2700
2701#ifdef CONFIG_SYSCTL
2702
2703static
2704int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
2705 void __user *buffer, size_t *lenp, loff_t *ppos)
2706{
2707 struct net *net;
2708 int delay;
2709 if (!write)
2710 return -EINVAL;
2711
2712 net = (struct net *)ctl->extra1;
2713 delay = net->ipv6.sysctl.flush_delay;
2714 proc_dointvec(ctl, write, buffer, lenp, ppos);
2715 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
2716 return 0;
2717}
2718
2719ctl_table ipv6_route_table_template[] = {
2720 {
2721 .procname = "flush",
2722 .data = &init_net.ipv6.sysctl.flush_delay,
2723 .maxlen = sizeof(int),
2724 .mode = 0200,
2725 .proc_handler = ipv6_sysctl_rtcache_flush
2726 },
2727 {
2728 .procname = "gc_thresh",
2729 .data = &ip6_dst_ops_template.gc_thresh,
2730 .maxlen = sizeof(int),
2731 .mode = 0644,
2732 .proc_handler = proc_dointvec,
2733 },
2734 {
2735 .procname = "max_size",
2736 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
2737 .maxlen = sizeof(int),
2738 .mode = 0644,
2739 .proc_handler = proc_dointvec,
2740 },
2741 {
2742 .procname = "gc_min_interval",
2743 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2744 .maxlen = sizeof(int),
2745 .mode = 0644,
2746 .proc_handler = proc_dointvec_jiffies,
2747 },
2748 {
2749 .procname = "gc_timeout",
2750 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2751 .maxlen = sizeof(int),
2752 .mode = 0644,
2753 .proc_handler = proc_dointvec_jiffies,
2754 },
2755 {
2756 .procname = "gc_interval",
2757 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2758 .maxlen = sizeof(int),
2759 .mode = 0644,
2760 .proc_handler = proc_dointvec_jiffies,
2761 },
2762 {
2763 .procname = "gc_elasticity",
2764 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2765 .maxlen = sizeof(int),
2766 .mode = 0644,
2767 .proc_handler = proc_dointvec,
2768 },
2769 {
2770 .procname = "mtu_expires",
2771 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2772 .maxlen = sizeof(int),
2773 .mode = 0644,
2774 .proc_handler = proc_dointvec_jiffies,
2775 },
2776 {
2777 .procname = "min_adv_mss",
2778 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2779 .maxlen = sizeof(int),
2780 .mode = 0644,
2781 .proc_handler = proc_dointvec,
2782 },
2783 {
2784 .procname = "gc_min_interval_ms",
2785 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2786 .maxlen = sizeof(int),
2787 .mode = 0644,
2788 .proc_handler = proc_dointvec_ms_jiffies,
2789 },
2790 { }
2791};
2792
2793struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2794{
2795 struct ctl_table *table;
2796
2797 table = kmemdup(ipv6_route_table_template,
2798 sizeof(ipv6_route_table_template),
2799 GFP_KERNEL);
2800
2801 if (table) {
2802 table[0].data = &net->ipv6.sysctl.flush_delay;
2803 table[0].extra1 = net;
2804 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2805 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2806 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2807 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2808 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2809 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2810 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2811 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2812 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2813 }
2814
2815 return table;
2816}
2817#endif
2818
2819static int __net_init ip6_route_net_init(struct net *net)
2820{
2821 int ret = -ENOMEM;
2822
2823 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
2824 sizeof(net->ipv6.ip6_dst_ops));
2825
2826 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
2827 goto out_ip6_dst_ops;
2828
2829 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
2830 sizeof(*net->ipv6.ip6_null_entry),
2831 GFP_KERNEL);
2832 if (!net->ipv6.ip6_null_entry)
2833 goto out_ip6_dst_entries;
2834 net->ipv6.ip6_null_entry->dst.path =
2835 (struct dst_entry *)net->ipv6.ip6_null_entry;
2836 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2837 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
2838 ip6_template_metrics, true);
2839
2840#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2841 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
2842 sizeof(*net->ipv6.ip6_prohibit_entry),
2843 GFP_KERNEL);
2844 if (!net->ipv6.ip6_prohibit_entry)
2845 goto out_ip6_null_entry;
2846 net->ipv6.ip6_prohibit_entry->dst.path =
2847 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2848 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2849 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
2850 ip6_template_metrics, true);
2851
2852 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
2853 sizeof(*net->ipv6.ip6_blk_hole_entry),
2854 GFP_KERNEL);
2855 if (!net->ipv6.ip6_blk_hole_entry)
2856 goto out_ip6_prohibit_entry;
2857 net->ipv6.ip6_blk_hole_entry->dst.path =
2858 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2859 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2860 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
2861 ip6_template_metrics, true);
2862#endif
2863
2864 net->ipv6.sysctl.flush_delay = 0;
2865 net->ipv6.sysctl.ip6_rt_max_size = 4096;
2866 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
2867 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
2868 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
2869 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
2870 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
2871 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
2872
2873#ifdef CONFIG_PROC_FS
2874 proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
2875 proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2876#endif
2877 net->ipv6.ip6_rt_gc_expire = 30*HZ;
2878
2879 ret = 0;
2880out:
2881 return ret;
2882
2883#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2884out_ip6_prohibit_entry:
2885 kfree(net->ipv6.ip6_prohibit_entry);
2886out_ip6_null_entry:
2887 kfree(net->ipv6.ip6_null_entry);
2888#endif
2889out_ip6_dst_entries:
2890 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2891out_ip6_dst_ops:
2892 goto out;
2893}
2894
2895static void __net_exit ip6_route_net_exit(struct net *net)
2896{
2897#ifdef CONFIG_PROC_FS
2898 proc_net_remove(net, "ipv6_route");
2899 proc_net_remove(net, "rt6_stats");
2900#endif
2901 kfree(net->ipv6.ip6_null_entry);
2902#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2903 kfree(net->ipv6.ip6_prohibit_entry);
2904 kfree(net->ipv6.ip6_blk_hole_entry);
2905#endif
2906 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2907}
2908
2909static struct pernet_operations ip6_route_net_ops = {
2910 .init = ip6_route_net_init,
2911 .exit = ip6_route_net_exit,
2912};
2913
2914static struct notifier_block ip6_route_dev_notifier = {
2915 .notifier_call = ip6_route_dev_notify,
2916 .priority = 0,
2917};
2918
2919int __init ip6_route_init(void)
2920{
2921 int ret;
2922
2923 ret = -ENOMEM;
2924 ip6_dst_ops_template.kmem_cachep =
2925 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2926 SLAB_HWCACHE_ALIGN, NULL);
2927 if (!ip6_dst_ops_template.kmem_cachep)
2928 goto out;
2929
2930 ret = dst_entries_init(&ip6_dst_blackhole_ops);
2931 if (ret)
2932 goto out_kmem_cache;
2933
2934 ret = register_pernet_subsys(&ip6_route_net_ops);
2935 if (ret)
2936 goto out_dst_entries;
2937
2938 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
2939
2940 /* Registering of the loopback is done before this portion of code,
2941 * the loopback reference in rt6_info will not be taken, do it
2942 * manually for init_net */
2943 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
2944 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2945 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2946 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
2947 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2948 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
2949 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2950 #endif
2951 ret = fib6_init();
2952 if (ret)
2953 goto out_register_subsys;
2954
2955 ret = xfrm6_init();
2956 if (ret)
2957 goto out_fib6_init;
2958
2959 ret = fib6_rules_init();
2960 if (ret)
2961 goto xfrm6_init;
2962
2963 ret = -ENOBUFS;
2964 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
2965 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
2966 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
2967 goto fib6_rules_init;
2968
2969 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
2970 if (ret)
2971 goto fib6_rules_init;
2972
2973out:
2974 return ret;
2975
2976fib6_rules_init:
2977 fib6_rules_cleanup();
2978xfrm6_init:
2979 xfrm6_fini();
2980out_fib6_init:
2981 fib6_gc_cleanup();
2982out_register_subsys:
2983 unregister_pernet_subsys(&ip6_route_net_ops);
2984out_dst_entries:
2985 dst_entries_destroy(&ip6_dst_blackhole_ops);
2986out_kmem_cache:
2987 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2988 goto out;
2989}
2990
2991void ip6_route_cleanup(void)
2992{
2993 unregister_netdevice_notifier(&ip6_route_dev_notifier);
2994 fib6_rules_cleanup();
2995 xfrm6_fini();
2996 fib6_gc_cleanup();
2997 unregister_pernet_subsys(&ip6_route_net_ops);
2998 dst_entries_destroy(&ip6_dst_blackhole_ops);
2999 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3000}