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Merge tag 'asoc-v5.7' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie...
[mirror_ubuntu-hirsute-kernel.git] / net / ipv6 / route.c
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 <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/dst_metadata.h>
55 #include <net/xfrm.h>
56 #include <net/netevent.h>
57 #include <net/netlink.h>
58 #include <net/rtnh.h>
59 #include <net/lwtunnel.h>
60 #include <net/ip_tunnels.h>
61 #include <net/l3mdev.h>
62 #include <net/ip.h>
63 #include <linux/uaccess.h>
64
65 #ifdef CONFIG_SYSCTL
66 #include <linux/sysctl.h>
67 #endif
68
69 static int ip6_rt_type_to_error(u8 fib6_type);
70
71 #define CREATE_TRACE_POINTS
72 #include <trace/events/fib6.h>
73 EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup);
74 #undef CREATE_TRACE_POINTS
75
76 enum rt6_nud_state {
77 RT6_NUD_FAIL_HARD = -3,
78 RT6_NUD_FAIL_PROBE = -2,
79 RT6_NUD_FAIL_DO_RR = -1,
80 RT6_NUD_SUCCEED = 1
81 };
82
83 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
84 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
85 static unsigned int ip6_mtu(const struct dst_entry *dst);
86 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
87 static void ip6_dst_destroy(struct dst_entry *);
88 static void ip6_dst_ifdown(struct dst_entry *,
89 struct net_device *dev, int how);
90 static int ip6_dst_gc(struct dst_ops *ops);
91
92 static int ip6_pkt_discard(struct sk_buff *skb);
93 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
94 static int ip6_pkt_prohibit(struct sk_buff *skb);
95 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
96 static void ip6_link_failure(struct sk_buff *skb);
97 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
98 struct sk_buff *skb, u32 mtu,
99 bool confirm_neigh);
100 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
101 struct sk_buff *skb);
102 static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
103 int strict);
104 static size_t rt6_nlmsg_size(struct fib6_info *f6i);
105 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
106 struct fib6_info *rt, struct dst_entry *dst,
107 struct in6_addr *dest, struct in6_addr *src,
108 int iif, int type, u32 portid, u32 seq,
109 unsigned int flags);
110 static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
111 const struct in6_addr *daddr,
112 const struct in6_addr *saddr);
113
114 #ifdef CONFIG_IPV6_ROUTE_INFO
115 static struct fib6_info *rt6_add_route_info(struct net *net,
116 const struct in6_addr *prefix, int prefixlen,
117 const struct in6_addr *gwaddr,
118 struct net_device *dev,
119 unsigned int pref);
120 static struct fib6_info *rt6_get_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 #endif
125
126 struct uncached_list {
127 spinlock_t lock;
128 struct list_head head;
129 };
130
131 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
132
133 void rt6_uncached_list_add(struct rt6_info *rt)
134 {
135 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
136
137 rt->rt6i_uncached_list = ul;
138
139 spin_lock_bh(&ul->lock);
140 list_add_tail(&rt->rt6i_uncached, &ul->head);
141 spin_unlock_bh(&ul->lock);
142 }
143
144 void rt6_uncached_list_del(struct rt6_info *rt)
145 {
146 if (!list_empty(&rt->rt6i_uncached)) {
147 struct uncached_list *ul = rt->rt6i_uncached_list;
148 struct net *net = dev_net(rt->dst.dev);
149
150 spin_lock_bh(&ul->lock);
151 list_del(&rt->rt6i_uncached);
152 atomic_dec(&net->ipv6.rt6_stats->fib_rt_uncache);
153 spin_unlock_bh(&ul->lock);
154 }
155 }
156
157 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
158 {
159 struct net_device *loopback_dev = net->loopback_dev;
160 int cpu;
161
162 if (dev == loopback_dev)
163 return;
164
165 for_each_possible_cpu(cpu) {
166 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
167 struct rt6_info *rt;
168
169 spin_lock_bh(&ul->lock);
170 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
171 struct inet6_dev *rt_idev = rt->rt6i_idev;
172 struct net_device *rt_dev = rt->dst.dev;
173
174 if (rt_idev->dev == dev) {
175 rt->rt6i_idev = in6_dev_get(loopback_dev);
176 in6_dev_put(rt_idev);
177 }
178
179 if (rt_dev == dev) {
180 rt->dst.dev = blackhole_netdev;
181 dev_hold(rt->dst.dev);
182 dev_put(rt_dev);
183 }
184 }
185 spin_unlock_bh(&ul->lock);
186 }
187 }
188
189 static inline const void *choose_neigh_daddr(const struct in6_addr *p,
190 struct sk_buff *skb,
191 const void *daddr)
192 {
193 if (!ipv6_addr_any(p))
194 return (const void *) p;
195 else if (skb)
196 return &ipv6_hdr(skb)->daddr;
197 return daddr;
198 }
199
200 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
201 struct net_device *dev,
202 struct sk_buff *skb,
203 const void *daddr)
204 {
205 struct neighbour *n;
206
207 daddr = choose_neigh_daddr(gw, skb, daddr);
208 n = __ipv6_neigh_lookup(dev, daddr);
209 if (n)
210 return n;
211
212 n = neigh_create(&nd_tbl, daddr, dev);
213 return IS_ERR(n) ? NULL : n;
214 }
215
216 static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst,
217 struct sk_buff *skb,
218 const void *daddr)
219 {
220 const struct rt6_info *rt = container_of(dst, struct rt6_info, dst);
221
222 return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any),
223 dst->dev, skb, daddr);
224 }
225
226 static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr)
227 {
228 struct net_device *dev = dst->dev;
229 struct rt6_info *rt = (struct rt6_info *)dst;
230
231 daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr);
232 if (!daddr)
233 return;
234 if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
235 return;
236 if (ipv6_addr_is_multicast((const struct in6_addr *)daddr))
237 return;
238 __ipv6_confirm_neigh(dev, daddr);
239 }
240
241 static struct dst_ops ip6_dst_ops_template = {
242 .family = AF_INET6,
243 .gc = ip6_dst_gc,
244 .gc_thresh = 1024,
245 .check = ip6_dst_check,
246 .default_advmss = ip6_default_advmss,
247 .mtu = ip6_mtu,
248 .cow_metrics = dst_cow_metrics_generic,
249 .destroy = ip6_dst_destroy,
250 .ifdown = ip6_dst_ifdown,
251 .negative_advice = ip6_negative_advice,
252 .link_failure = ip6_link_failure,
253 .update_pmtu = ip6_rt_update_pmtu,
254 .redirect = rt6_do_redirect,
255 .local_out = __ip6_local_out,
256 .neigh_lookup = ip6_dst_neigh_lookup,
257 .confirm_neigh = ip6_confirm_neigh,
258 };
259
260 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
261 {
262 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
263
264 return mtu ? : dst->dev->mtu;
265 }
266
267 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
268 struct sk_buff *skb, u32 mtu,
269 bool confirm_neigh)
270 {
271 }
272
273 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
274 struct sk_buff *skb)
275 {
276 }
277
278 static struct dst_ops ip6_dst_blackhole_ops = {
279 .family = AF_INET6,
280 .destroy = ip6_dst_destroy,
281 .check = ip6_dst_check,
282 .mtu = ip6_blackhole_mtu,
283 .default_advmss = ip6_default_advmss,
284 .update_pmtu = ip6_rt_blackhole_update_pmtu,
285 .redirect = ip6_rt_blackhole_redirect,
286 .cow_metrics = dst_cow_metrics_generic,
287 .neigh_lookup = ip6_dst_neigh_lookup,
288 };
289
290 static const u32 ip6_template_metrics[RTAX_MAX] = {
291 [RTAX_HOPLIMIT - 1] = 0,
292 };
293
294 static const struct fib6_info fib6_null_entry_template = {
295 .fib6_flags = (RTF_REJECT | RTF_NONEXTHOP),
296 .fib6_protocol = RTPROT_KERNEL,
297 .fib6_metric = ~(u32)0,
298 .fib6_ref = REFCOUNT_INIT(1),
299 .fib6_type = RTN_UNREACHABLE,
300 .fib6_metrics = (struct dst_metrics *)&dst_default_metrics,
301 };
302
303 static const struct rt6_info ip6_null_entry_template = {
304 .dst = {
305 .__refcnt = ATOMIC_INIT(1),
306 .__use = 1,
307 .obsolete = DST_OBSOLETE_FORCE_CHK,
308 .error = -ENETUNREACH,
309 .input = ip6_pkt_discard,
310 .output = ip6_pkt_discard_out,
311 },
312 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
313 };
314
315 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
316
317 static const struct rt6_info ip6_prohibit_entry_template = {
318 .dst = {
319 .__refcnt = ATOMIC_INIT(1),
320 .__use = 1,
321 .obsolete = DST_OBSOLETE_FORCE_CHK,
322 .error = -EACCES,
323 .input = ip6_pkt_prohibit,
324 .output = ip6_pkt_prohibit_out,
325 },
326 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
327 };
328
329 static const struct rt6_info ip6_blk_hole_entry_template = {
330 .dst = {
331 .__refcnt = ATOMIC_INIT(1),
332 .__use = 1,
333 .obsolete = DST_OBSOLETE_FORCE_CHK,
334 .error = -EINVAL,
335 .input = dst_discard,
336 .output = dst_discard_out,
337 },
338 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
339 };
340
341 #endif
342
343 static void rt6_info_init(struct rt6_info *rt)
344 {
345 struct dst_entry *dst = &rt->dst;
346
347 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
348 INIT_LIST_HEAD(&rt->rt6i_uncached);
349 }
350
351 /* allocate dst with ip6_dst_ops */
352 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
353 int flags)
354 {
355 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
356 1, DST_OBSOLETE_FORCE_CHK, flags);
357
358 if (rt) {
359 rt6_info_init(rt);
360 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
361 }
362
363 return rt;
364 }
365 EXPORT_SYMBOL(ip6_dst_alloc);
366
367 static void ip6_dst_destroy(struct dst_entry *dst)
368 {
369 struct rt6_info *rt = (struct rt6_info *)dst;
370 struct fib6_info *from;
371 struct inet6_dev *idev;
372
373 ip_dst_metrics_put(dst);
374 rt6_uncached_list_del(rt);
375
376 idev = rt->rt6i_idev;
377 if (idev) {
378 rt->rt6i_idev = NULL;
379 in6_dev_put(idev);
380 }
381
382 from = xchg((__force struct fib6_info **)&rt->from, NULL);
383 fib6_info_release(from);
384 }
385
386 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
387 int how)
388 {
389 struct rt6_info *rt = (struct rt6_info *)dst;
390 struct inet6_dev *idev = rt->rt6i_idev;
391 struct net_device *loopback_dev =
392 dev_net(dev)->loopback_dev;
393
394 if (idev && idev->dev != loopback_dev) {
395 struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
396 if (loopback_idev) {
397 rt->rt6i_idev = loopback_idev;
398 in6_dev_put(idev);
399 }
400 }
401 }
402
403 static bool __rt6_check_expired(const struct rt6_info *rt)
404 {
405 if (rt->rt6i_flags & RTF_EXPIRES)
406 return time_after(jiffies, rt->dst.expires);
407 else
408 return false;
409 }
410
411 static bool rt6_check_expired(const struct rt6_info *rt)
412 {
413 struct fib6_info *from;
414
415 from = rcu_dereference(rt->from);
416
417 if (rt->rt6i_flags & RTF_EXPIRES) {
418 if (time_after(jiffies, rt->dst.expires))
419 return true;
420 } else if (from) {
421 return rt->dst.obsolete != DST_OBSOLETE_FORCE_CHK ||
422 fib6_check_expired(from);
423 }
424 return false;
425 }
426
427 void fib6_select_path(const struct net *net, struct fib6_result *res,
428 struct flowi6 *fl6, int oif, bool have_oif_match,
429 const struct sk_buff *skb, int strict)
430 {
431 struct fib6_info *sibling, *next_sibling;
432 struct fib6_info *match = res->f6i;
433
434 if ((!match->fib6_nsiblings && !match->nh) || have_oif_match)
435 goto out;
436
437 /* We might have already computed the hash for ICMPv6 errors. In such
438 * case it will always be non-zero. Otherwise now is the time to do it.
439 */
440 if (!fl6->mp_hash &&
441 (!match->nh || nexthop_is_multipath(match->nh)))
442 fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL);
443
444 if (unlikely(match->nh)) {
445 nexthop_path_fib6_result(res, fl6->mp_hash);
446 return;
447 }
448
449 if (fl6->mp_hash <= atomic_read(&match->fib6_nh->fib_nh_upper_bound))
450 goto out;
451
452 list_for_each_entry_safe(sibling, next_sibling, &match->fib6_siblings,
453 fib6_siblings) {
454 const struct fib6_nh *nh = sibling->fib6_nh;
455 int nh_upper_bound;
456
457 nh_upper_bound = atomic_read(&nh->fib_nh_upper_bound);
458 if (fl6->mp_hash > nh_upper_bound)
459 continue;
460 if (rt6_score_route(nh, sibling->fib6_flags, oif, strict) < 0)
461 break;
462 match = sibling;
463 break;
464 }
465
466 out:
467 res->f6i = match;
468 res->nh = match->fib6_nh;
469 }
470
471 /*
472 * Route lookup. rcu_read_lock() should be held.
473 */
474
475 static bool __rt6_device_match(struct net *net, const struct fib6_nh *nh,
476 const struct in6_addr *saddr, int oif, int flags)
477 {
478 const struct net_device *dev;
479
480 if (nh->fib_nh_flags & RTNH_F_DEAD)
481 return false;
482
483 dev = nh->fib_nh_dev;
484 if (oif) {
485 if (dev->ifindex == oif)
486 return true;
487 } else {
488 if (ipv6_chk_addr(net, saddr, dev,
489 flags & RT6_LOOKUP_F_IFACE))
490 return true;
491 }
492
493 return false;
494 }
495
496 struct fib6_nh_dm_arg {
497 struct net *net;
498 const struct in6_addr *saddr;
499 int oif;
500 int flags;
501 struct fib6_nh *nh;
502 };
503
504 static int __rt6_nh_dev_match(struct fib6_nh *nh, void *_arg)
505 {
506 struct fib6_nh_dm_arg *arg = _arg;
507
508 arg->nh = nh;
509 return __rt6_device_match(arg->net, nh, arg->saddr, arg->oif,
510 arg->flags);
511 }
512
513 /* returns fib6_nh from nexthop or NULL */
514 static struct fib6_nh *rt6_nh_dev_match(struct net *net, struct nexthop *nh,
515 struct fib6_result *res,
516 const struct in6_addr *saddr,
517 int oif, int flags)
518 {
519 struct fib6_nh_dm_arg arg = {
520 .net = net,
521 .saddr = saddr,
522 .oif = oif,
523 .flags = flags,
524 };
525
526 if (nexthop_is_blackhole(nh))
527 return NULL;
528
529 if (nexthop_for_each_fib6_nh(nh, __rt6_nh_dev_match, &arg))
530 return arg.nh;
531
532 return NULL;
533 }
534
535 static void rt6_device_match(struct net *net, struct fib6_result *res,
536 const struct in6_addr *saddr, int oif, int flags)
537 {
538 struct fib6_info *f6i = res->f6i;
539 struct fib6_info *spf6i;
540 struct fib6_nh *nh;
541
542 if (!oif && ipv6_addr_any(saddr)) {
543 if (unlikely(f6i->nh)) {
544 nh = nexthop_fib6_nh(f6i->nh);
545 if (nexthop_is_blackhole(f6i->nh))
546 goto out_blackhole;
547 } else {
548 nh = f6i->fib6_nh;
549 }
550 if (!(nh->fib_nh_flags & RTNH_F_DEAD))
551 goto out;
552 }
553
554 for (spf6i = f6i; spf6i; spf6i = rcu_dereference(spf6i->fib6_next)) {
555 bool matched = false;
556
557 if (unlikely(spf6i->nh)) {
558 nh = rt6_nh_dev_match(net, spf6i->nh, res, saddr,
559 oif, flags);
560 if (nh)
561 matched = true;
562 } else {
563 nh = spf6i->fib6_nh;
564 if (__rt6_device_match(net, nh, saddr, oif, flags))
565 matched = true;
566 }
567 if (matched) {
568 res->f6i = spf6i;
569 goto out;
570 }
571 }
572
573 if (oif && flags & RT6_LOOKUP_F_IFACE) {
574 res->f6i = net->ipv6.fib6_null_entry;
575 nh = res->f6i->fib6_nh;
576 goto out;
577 }
578
579 if (unlikely(f6i->nh)) {
580 nh = nexthop_fib6_nh(f6i->nh);
581 if (nexthop_is_blackhole(f6i->nh))
582 goto out_blackhole;
583 } else {
584 nh = f6i->fib6_nh;
585 }
586
587 if (nh->fib_nh_flags & RTNH_F_DEAD) {
588 res->f6i = net->ipv6.fib6_null_entry;
589 nh = res->f6i->fib6_nh;
590 }
591 out:
592 res->nh = nh;
593 res->fib6_type = res->f6i->fib6_type;
594 res->fib6_flags = res->f6i->fib6_flags;
595 return;
596
597 out_blackhole:
598 res->fib6_flags |= RTF_REJECT;
599 res->fib6_type = RTN_BLACKHOLE;
600 res->nh = nh;
601 }
602
603 #ifdef CONFIG_IPV6_ROUTER_PREF
604 struct __rt6_probe_work {
605 struct work_struct work;
606 struct in6_addr target;
607 struct net_device *dev;
608 };
609
610 static void rt6_probe_deferred(struct work_struct *w)
611 {
612 struct in6_addr mcaddr;
613 struct __rt6_probe_work *work =
614 container_of(w, struct __rt6_probe_work, work);
615
616 addrconf_addr_solict_mult(&work->target, &mcaddr);
617 ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
618 dev_put(work->dev);
619 kfree(work);
620 }
621
622 static void rt6_probe(struct fib6_nh *fib6_nh)
623 {
624 struct __rt6_probe_work *work = NULL;
625 const struct in6_addr *nh_gw;
626 unsigned long last_probe;
627 struct neighbour *neigh;
628 struct net_device *dev;
629 struct inet6_dev *idev;
630
631 /*
632 * Okay, this does not seem to be appropriate
633 * for now, however, we need to check if it
634 * is really so; aka Router Reachability Probing.
635 *
636 * Router Reachability Probe MUST be rate-limited
637 * to no more than one per minute.
638 */
639 if (!fib6_nh->fib_nh_gw_family)
640 return;
641
642 nh_gw = &fib6_nh->fib_nh_gw6;
643 dev = fib6_nh->fib_nh_dev;
644 rcu_read_lock_bh();
645 last_probe = READ_ONCE(fib6_nh->last_probe);
646 idev = __in6_dev_get(dev);
647 neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
648 if (neigh) {
649 if (neigh->nud_state & NUD_VALID)
650 goto out;
651
652 write_lock(&neigh->lock);
653 if (!(neigh->nud_state & NUD_VALID) &&
654 time_after(jiffies,
655 neigh->updated + idev->cnf.rtr_probe_interval)) {
656 work = kmalloc(sizeof(*work), GFP_ATOMIC);
657 if (work)
658 __neigh_set_probe_once(neigh);
659 }
660 write_unlock(&neigh->lock);
661 } else if (time_after(jiffies, last_probe +
662 idev->cnf.rtr_probe_interval)) {
663 work = kmalloc(sizeof(*work), GFP_ATOMIC);
664 }
665
666 if (!work || cmpxchg(&fib6_nh->last_probe,
667 last_probe, jiffies) != last_probe) {
668 kfree(work);
669 } else {
670 INIT_WORK(&work->work, rt6_probe_deferred);
671 work->target = *nh_gw;
672 dev_hold(dev);
673 work->dev = dev;
674 schedule_work(&work->work);
675 }
676
677 out:
678 rcu_read_unlock_bh();
679 }
680 #else
681 static inline void rt6_probe(struct fib6_nh *fib6_nh)
682 {
683 }
684 #endif
685
686 /*
687 * Default Router Selection (RFC 2461 6.3.6)
688 */
689 static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
690 {
691 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
692 struct neighbour *neigh;
693
694 rcu_read_lock_bh();
695 neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev,
696 &fib6_nh->fib_nh_gw6);
697 if (neigh) {
698 read_lock(&neigh->lock);
699 if (neigh->nud_state & NUD_VALID)
700 ret = RT6_NUD_SUCCEED;
701 #ifdef CONFIG_IPV6_ROUTER_PREF
702 else if (!(neigh->nud_state & NUD_FAILED))
703 ret = RT6_NUD_SUCCEED;
704 else
705 ret = RT6_NUD_FAIL_PROBE;
706 #endif
707 read_unlock(&neigh->lock);
708 } else {
709 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
710 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
711 }
712 rcu_read_unlock_bh();
713
714 return ret;
715 }
716
717 static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
718 int strict)
719 {
720 int m = 0;
721
722 if (!oif || nh->fib_nh_dev->ifindex == oif)
723 m = 2;
724
725 if (!m && (strict & RT6_LOOKUP_F_IFACE))
726 return RT6_NUD_FAIL_HARD;
727 #ifdef CONFIG_IPV6_ROUTER_PREF
728 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(fib6_flags)) << 2;
729 #endif
730 if ((strict & RT6_LOOKUP_F_REACHABLE) &&
731 !(fib6_flags & RTF_NONEXTHOP) && nh->fib_nh_gw_family) {
732 int n = rt6_check_neigh(nh);
733 if (n < 0)
734 return n;
735 }
736 return m;
737 }
738
739 static bool find_match(struct fib6_nh *nh, u32 fib6_flags,
740 int oif, int strict, int *mpri, bool *do_rr)
741 {
742 bool match_do_rr = false;
743 bool rc = false;
744 int m;
745
746 if (nh->fib_nh_flags & RTNH_F_DEAD)
747 goto out;
748
749 if (ip6_ignore_linkdown(nh->fib_nh_dev) &&
750 nh->fib_nh_flags & RTNH_F_LINKDOWN &&
751 !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
752 goto out;
753
754 m = rt6_score_route(nh, fib6_flags, oif, strict);
755 if (m == RT6_NUD_FAIL_DO_RR) {
756 match_do_rr = true;
757 m = 0; /* lowest valid score */
758 } else if (m == RT6_NUD_FAIL_HARD) {
759 goto out;
760 }
761
762 if (strict & RT6_LOOKUP_F_REACHABLE)
763 rt6_probe(nh);
764
765 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
766 if (m > *mpri) {
767 *do_rr = match_do_rr;
768 *mpri = m;
769 rc = true;
770 }
771 out:
772 return rc;
773 }
774
775 struct fib6_nh_frl_arg {
776 u32 flags;
777 int oif;
778 int strict;
779 int *mpri;
780 bool *do_rr;
781 struct fib6_nh *nh;
782 };
783
784 static int rt6_nh_find_match(struct fib6_nh *nh, void *_arg)
785 {
786 struct fib6_nh_frl_arg *arg = _arg;
787
788 arg->nh = nh;
789 return find_match(nh, arg->flags, arg->oif, arg->strict,
790 arg->mpri, arg->do_rr);
791 }
792
793 static void __find_rr_leaf(struct fib6_info *f6i_start,
794 struct fib6_info *nomatch, u32 metric,
795 struct fib6_result *res, struct fib6_info **cont,
796 int oif, int strict, bool *do_rr, int *mpri)
797 {
798 struct fib6_info *f6i;
799
800 for (f6i = f6i_start;
801 f6i && f6i != nomatch;
802 f6i = rcu_dereference(f6i->fib6_next)) {
803 bool matched = false;
804 struct fib6_nh *nh;
805
806 if (cont && f6i->fib6_metric != metric) {
807 *cont = f6i;
808 return;
809 }
810
811 if (fib6_check_expired(f6i))
812 continue;
813
814 if (unlikely(f6i->nh)) {
815 struct fib6_nh_frl_arg arg = {
816 .flags = f6i->fib6_flags,
817 .oif = oif,
818 .strict = strict,
819 .mpri = mpri,
820 .do_rr = do_rr
821 };
822
823 if (nexthop_is_blackhole(f6i->nh)) {
824 res->fib6_flags = RTF_REJECT;
825 res->fib6_type = RTN_BLACKHOLE;
826 res->f6i = f6i;
827 res->nh = nexthop_fib6_nh(f6i->nh);
828 return;
829 }
830 if (nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_find_match,
831 &arg)) {
832 matched = true;
833 nh = arg.nh;
834 }
835 } else {
836 nh = f6i->fib6_nh;
837 if (find_match(nh, f6i->fib6_flags, oif, strict,
838 mpri, do_rr))
839 matched = true;
840 }
841 if (matched) {
842 res->f6i = f6i;
843 res->nh = nh;
844 res->fib6_flags = f6i->fib6_flags;
845 res->fib6_type = f6i->fib6_type;
846 }
847 }
848 }
849
850 static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf,
851 struct fib6_info *rr_head, int oif, int strict,
852 bool *do_rr, struct fib6_result *res)
853 {
854 u32 metric = rr_head->fib6_metric;
855 struct fib6_info *cont = NULL;
856 int mpri = -1;
857
858 __find_rr_leaf(rr_head, NULL, metric, res, &cont,
859 oif, strict, do_rr, &mpri);
860
861 __find_rr_leaf(leaf, rr_head, metric, res, &cont,
862 oif, strict, do_rr, &mpri);
863
864 if (res->f6i || !cont)
865 return;
866
867 __find_rr_leaf(cont, NULL, metric, res, NULL,
868 oif, strict, do_rr, &mpri);
869 }
870
871 static void rt6_select(struct net *net, struct fib6_node *fn, int oif,
872 struct fib6_result *res, int strict)
873 {
874 struct fib6_info *leaf = rcu_dereference(fn->leaf);
875 struct fib6_info *rt0;
876 bool do_rr = false;
877 int key_plen;
878
879 /* make sure this function or its helpers sets f6i */
880 res->f6i = NULL;
881
882 if (!leaf || leaf == net->ipv6.fib6_null_entry)
883 goto out;
884
885 rt0 = rcu_dereference(fn->rr_ptr);
886 if (!rt0)
887 rt0 = leaf;
888
889 /* Double check to make sure fn is not an intermediate node
890 * and fn->leaf does not points to its child's leaf
891 * (This might happen if all routes under fn are deleted from
892 * the tree and fib6_repair_tree() is called on the node.)
893 */
894 key_plen = rt0->fib6_dst.plen;
895 #ifdef CONFIG_IPV6_SUBTREES
896 if (rt0->fib6_src.plen)
897 key_plen = rt0->fib6_src.plen;
898 #endif
899 if (fn->fn_bit != key_plen)
900 goto out;
901
902 find_rr_leaf(fn, leaf, rt0, oif, strict, &do_rr, res);
903 if (do_rr) {
904 struct fib6_info *next = rcu_dereference(rt0->fib6_next);
905
906 /* no entries matched; do round-robin */
907 if (!next || next->fib6_metric != rt0->fib6_metric)
908 next = leaf;
909
910 if (next != rt0) {
911 spin_lock_bh(&leaf->fib6_table->tb6_lock);
912 /* make sure next is not being deleted from the tree */
913 if (next->fib6_node)
914 rcu_assign_pointer(fn->rr_ptr, next);
915 spin_unlock_bh(&leaf->fib6_table->tb6_lock);
916 }
917 }
918
919 out:
920 if (!res->f6i) {
921 res->f6i = net->ipv6.fib6_null_entry;
922 res->nh = res->f6i->fib6_nh;
923 res->fib6_flags = res->f6i->fib6_flags;
924 res->fib6_type = res->f6i->fib6_type;
925 }
926 }
927
928 static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res)
929 {
930 return (res->f6i->fib6_flags & RTF_NONEXTHOP) ||
931 res->nh->fib_nh_gw_family;
932 }
933
934 #ifdef CONFIG_IPV6_ROUTE_INFO
935 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
936 const struct in6_addr *gwaddr)
937 {
938 struct net *net = dev_net(dev);
939 struct route_info *rinfo = (struct route_info *) opt;
940 struct in6_addr prefix_buf, *prefix;
941 unsigned int pref;
942 unsigned long lifetime;
943 struct fib6_info *rt;
944
945 if (len < sizeof(struct route_info)) {
946 return -EINVAL;
947 }
948
949 /* Sanity check for prefix_len and length */
950 if (rinfo->length > 3) {
951 return -EINVAL;
952 } else if (rinfo->prefix_len > 128) {
953 return -EINVAL;
954 } else if (rinfo->prefix_len > 64) {
955 if (rinfo->length < 2) {
956 return -EINVAL;
957 }
958 } else if (rinfo->prefix_len > 0) {
959 if (rinfo->length < 1) {
960 return -EINVAL;
961 }
962 }
963
964 pref = rinfo->route_pref;
965 if (pref == ICMPV6_ROUTER_PREF_INVALID)
966 return -EINVAL;
967
968 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
969
970 if (rinfo->length == 3)
971 prefix = (struct in6_addr *)rinfo->prefix;
972 else {
973 /* this function is safe */
974 ipv6_addr_prefix(&prefix_buf,
975 (struct in6_addr *)rinfo->prefix,
976 rinfo->prefix_len);
977 prefix = &prefix_buf;
978 }
979
980 if (rinfo->prefix_len == 0)
981 rt = rt6_get_dflt_router(net, gwaddr, dev);
982 else
983 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
984 gwaddr, dev);
985
986 if (rt && !lifetime) {
987 ip6_del_rt(net, rt);
988 rt = NULL;
989 }
990
991 if (!rt && lifetime)
992 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
993 dev, pref);
994 else if (rt)
995 rt->fib6_flags = RTF_ROUTEINFO |
996 (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
997
998 if (rt) {
999 if (!addrconf_finite_timeout(lifetime))
1000 fib6_clean_expires(rt);
1001 else
1002 fib6_set_expires(rt, jiffies + HZ * lifetime);
1003
1004 fib6_info_release(rt);
1005 }
1006 return 0;
1007 }
1008 #endif
1009
1010 /*
1011 * Misc support functions
1012 */
1013
1014 /* called with rcu_lock held */
1015 static struct net_device *ip6_rt_get_dev_rcu(const struct fib6_result *res)
1016 {
1017 struct net_device *dev = res->nh->fib_nh_dev;
1018
1019 if (res->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) {
1020 /* for copies of local routes, dst->dev needs to be the
1021 * device if it is a master device, the master device if
1022 * device is enslaved, and the loopback as the default
1023 */
1024 if (netif_is_l3_slave(dev) &&
1025 !rt6_need_strict(&res->f6i->fib6_dst.addr))
1026 dev = l3mdev_master_dev_rcu(dev);
1027 else if (!netif_is_l3_master(dev))
1028 dev = dev_net(dev)->loopback_dev;
1029 /* last case is netif_is_l3_master(dev) is true in which
1030 * case we want dev returned to be dev
1031 */
1032 }
1033
1034 return dev;
1035 }
1036
1037 static const int fib6_prop[RTN_MAX + 1] = {
1038 [RTN_UNSPEC] = 0,
1039 [RTN_UNICAST] = 0,
1040 [RTN_LOCAL] = 0,
1041 [RTN_BROADCAST] = 0,
1042 [RTN_ANYCAST] = 0,
1043 [RTN_MULTICAST] = 0,
1044 [RTN_BLACKHOLE] = -EINVAL,
1045 [RTN_UNREACHABLE] = -EHOSTUNREACH,
1046 [RTN_PROHIBIT] = -EACCES,
1047 [RTN_THROW] = -EAGAIN,
1048 [RTN_NAT] = -EINVAL,
1049 [RTN_XRESOLVE] = -EINVAL,
1050 };
1051
1052 static int ip6_rt_type_to_error(u8 fib6_type)
1053 {
1054 return fib6_prop[fib6_type];
1055 }
1056
1057 static unsigned short fib6_info_dst_flags(struct fib6_info *rt)
1058 {
1059 unsigned short flags = 0;
1060
1061 if (rt->dst_nocount)
1062 flags |= DST_NOCOUNT;
1063 if (rt->dst_nopolicy)
1064 flags |= DST_NOPOLICY;
1065 if (rt->dst_host)
1066 flags |= DST_HOST;
1067
1068 return flags;
1069 }
1070
1071 static void ip6_rt_init_dst_reject(struct rt6_info *rt, u8 fib6_type)
1072 {
1073 rt->dst.error = ip6_rt_type_to_error(fib6_type);
1074
1075 switch (fib6_type) {
1076 case RTN_BLACKHOLE:
1077 rt->dst.output = dst_discard_out;
1078 rt->dst.input = dst_discard;
1079 break;
1080 case RTN_PROHIBIT:
1081 rt->dst.output = ip6_pkt_prohibit_out;
1082 rt->dst.input = ip6_pkt_prohibit;
1083 break;
1084 case RTN_THROW:
1085 case RTN_UNREACHABLE:
1086 default:
1087 rt->dst.output = ip6_pkt_discard_out;
1088 rt->dst.input = ip6_pkt_discard;
1089 break;
1090 }
1091 }
1092
1093 static void ip6_rt_init_dst(struct rt6_info *rt, const struct fib6_result *res)
1094 {
1095 struct fib6_info *f6i = res->f6i;
1096
1097 if (res->fib6_flags & RTF_REJECT) {
1098 ip6_rt_init_dst_reject(rt, res->fib6_type);
1099 return;
1100 }
1101
1102 rt->dst.error = 0;
1103 rt->dst.output = ip6_output;
1104
1105 if (res->fib6_type == RTN_LOCAL || res->fib6_type == RTN_ANYCAST) {
1106 rt->dst.input = ip6_input;
1107 } else if (ipv6_addr_type(&f6i->fib6_dst.addr) & IPV6_ADDR_MULTICAST) {
1108 rt->dst.input = ip6_mc_input;
1109 } else {
1110 rt->dst.input = ip6_forward;
1111 }
1112
1113 if (res->nh->fib_nh_lws) {
1114 rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws);
1115 lwtunnel_set_redirect(&rt->dst);
1116 }
1117
1118 rt->dst.lastuse = jiffies;
1119 }
1120
1121 /* Caller must already hold reference to @from */
1122 static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
1123 {
1124 rt->rt6i_flags &= ~RTF_EXPIRES;
1125 rcu_assign_pointer(rt->from, from);
1126 ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
1127 }
1128
1129 /* Caller must already hold reference to f6i in result */
1130 static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res)
1131 {
1132 const struct fib6_nh *nh = res->nh;
1133 const struct net_device *dev = nh->fib_nh_dev;
1134 struct fib6_info *f6i = res->f6i;
1135
1136 ip6_rt_init_dst(rt, res);
1137
1138 rt->rt6i_dst = f6i->fib6_dst;
1139 rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
1140 rt->rt6i_flags = res->fib6_flags;
1141 if (nh->fib_nh_gw_family) {
1142 rt->rt6i_gateway = nh->fib_nh_gw6;
1143 rt->rt6i_flags |= RTF_GATEWAY;
1144 }
1145 rt6_set_from(rt, f6i);
1146 #ifdef CONFIG_IPV6_SUBTREES
1147 rt->rt6i_src = f6i->fib6_src;
1148 #endif
1149 }
1150
1151 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
1152 struct in6_addr *saddr)
1153 {
1154 struct fib6_node *pn, *sn;
1155 while (1) {
1156 if (fn->fn_flags & RTN_TL_ROOT)
1157 return NULL;
1158 pn = rcu_dereference(fn->parent);
1159 sn = FIB6_SUBTREE(pn);
1160 if (sn && sn != fn)
1161 fn = fib6_node_lookup(sn, NULL, saddr);
1162 else
1163 fn = pn;
1164 if (fn->fn_flags & RTN_RTINFO)
1165 return fn;
1166 }
1167 }
1168
1169 static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
1170 {
1171 struct rt6_info *rt = *prt;
1172
1173 if (dst_hold_safe(&rt->dst))
1174 return true;
1175 if (net) {
1176 rt = net->ipv6.ip6_null_entry;
1177 dst_hold(&rt->dst);
1178 } else {
1179 rt = NULL;
1180 }
1181 *prt = rt;
1182 return false;
1183 }
1184
1185 /* called with rcu_lock held */
1186 static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res)
1187 {
1188 struct net_device *dev = res->nh->fib_nh_dev;
1189 struct fib6_info *f6i = res->f6i;
1190 unsigned short flags;
1191 struct rt6_info *nrt;
1192
1193 if (!fib6_info_hold_safe(f6i))
1194 goto fallback;
1195
1196 flags = fib6_info_dst_flags(f6i);
1197 nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
1198 if (!nrt) {
1199 fib6_info_release(f6i);
1200 goto fallback;
1201 }
1202
1203 ip6_rt_copy_init(nrt, res);
1204 return nrt;
1205
1206 fallback:
1207 nrt = dev_net(dev)->ipv6.ip6_null_entry;
1208 dst_hold(&nrt->dst);
1209 return nrt;
1210 }
1211
1212 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
1213 struct fib6_table *table,
1214 struct flowi6 *fl6,
1215 const struct sk_buff *skb,
1216 int flags)
1217 {
1218 struct fib6_result res = {};
1219 struct fib6_node *fn;
1220 struct rt6_info *rt;
1221
1222 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1223 flags &= ~RT6_LOOKUP_F_IFACE;
1224
1225 rcu_read_lock();
1226 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1227 restart:
1228 res.f6i = rcu_dereference(fn->leaf);
1229 if (!res.f6i)
1230 res.f6i = net->ipv6.fib6_null_entry;
1231 else
1232 rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif,
1233 flags);
1234
1235 if (res.f6i == net->ipv6.fib6_null_entry) {
1236 fn = fib6_backtrack(fn, &fl6->saddr);
1237 if (fn)
1238 goto restart;
1239
1240 rt = net->ipv6.ip6_null_entry;
1241 dst_hold(&rt->dst);
1242 goto out;
1243 } else if (res.fib6_flags & RTF_REJECT) {
1244 goto do_create;
1245 }
1246
1247 fib6_select_path(net, &res, fl6, fl6->flowi6_oif,
1248 fl6->flowi6_oif != 0, skb, flags);
1249
1250 /* Search through exception table */
1251 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
1252 if (rt) {
1253 if (ip6_hold_safe(net, &rt))
1254 dst_use_noref(&rt->dst, jiffies);
1255 } else {
1256 do_create:
1257 rt = ip6_create_rt_rcu(&res);
1258 }
1259
1260 out:
1261 trace_fib6_table_lookup(net, &res, table, fl6);
1262
1263 rcu_read_unlock();
1264
1265 return rt;
1266 }
1267
1268 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
1269 const struct sk_buff *skb, int flags)
1270 {
1271 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup);
1272 }
1273 EXPORT_SYMBOL_GPL(ip6_route_lookup);
1274
1275 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
1276 const struct in6_addr *saddr, int oif,
1277 const struct sk_buff *skb, int strict)
1278 {
1279 struct flowi6 fl6 = {
1280 .flowi6_oif = oif,
1281 .daddr = *daddr,
1282 };
1283 struct dst_entry *dst;
1284 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
1285
1286 if (saddr) {
1287 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
1288 flags |= RT6_LOOKUP_F_HAS_SADDR;
1289 }
1290
1291 dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
1292 if (dst->error == 0)
1293 return (struct rt6_info *) dst;
1294
1295 dst_release(dst);
1296
1297 return NULL;
1298 }
1299 EXPORT_SYMBOL(rt6_lookup);
1300
1301 /* ip6_ins_rt is called with FREE table->tb6_lock.
1302 * It takes new route entry, the addition fails by any reason the
1303 * route is released.
1304 * Caller must hold dst before calling it.
1305 */
1306
1307 static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info,
1308 struct netlink_ext_ack *extack)
1309 {
1310 int err;
1311 struct fib6_table *table;
1312
1313 table = rt->fib6_table;
1314 spin_lock_bh(&table->tb6_lock);
1315 err = fib6_add(&table->tb6_root, rt, info, extack);
1316 spin_unlock_bh(&table->tb6_lock);
1317
1318 return err;
1319 }
1320
1321 int ip6_ins_rt(struct net *net, struct fib6_info *rt)
1322 {
1323 struct nl_info info = { .nl_net = net, };
1324
1325 return __ip6_ins_rt(rt, &info, NULL);
1326 }
1327
1328 static struct rt6_info *ip6_rt_cache_alloc(const struct fib6_result *res,
1329 const struct in6_addr *daddr,
1330 const struct in6_addr *saddr)
1331 {
1332 struct fib6_info *f6i = res->f6i;
1333 struct net_device *dev;
1334 struct rt6_info *rt;
1335
1336 /*
1337 * Clone the route.
1338 */
1339
1340 if (!fib6_info_hold_safe(f6i))
1341 return NULL;
1342
1343 dev = ip6_rt_get_dev_rcu(res);
1344 rt = ip6_dst_alloc(dev_net(dev), dev, 0);
1345 if (!rt) {
1346 fib6_info_release(f6i);
1347 return NULL;
1348 }
1349
1350 ip6_rt_copy_init(rt, res);
1351 rt->rt6i_flags |= RTF_CACHE;
1352 rt->dst.flags |= DST_HOST;
1353 rt->rt6i_dst.addr = *daddr;
1354 rt->rt6i_dst.plen = 128;
1355
1356 if (!rt6_is_gw_or_nonexthop(res)) {
1357 if (f6i->fib6_dst.plen != 128 &&
1358 ipv6_addr_equal(&f6i->fib6_dst.addr, daddr))
1359 rt->rt6i_flags |= RTF_ANYCAST;
1360 #ifdef CONFIG_IPV6_SUBTREES
1361 if (rt->rt6i_src.plen && saddr) {
1362 rt->rt6i_src.addr = *saddr;
1363 rt->rt6i_src.plen = 128;
1364 }
1365 #endif
1366 }
1367
1368 return rt;
1369 }
1370
1371 static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res)
1372 {
1373 struct fib6_info *f6i = res->f6i;
1374 unsigned short flags = fib6_info_dst_flags(f6i);
1375 struct net_device *dev;
1376 struct rt6_info *pcpu_rt;
1377
1378 if (!fib6_info_hold_safe(f6i))
1379 return NULL;
1380
1381 rcu_read_lock();
1382 dev = ip6_rt_get_dev_rcu(res);
1383 pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags);
1384 rcu_read_unlock();
1385 if (!pcpu_rt) {
1386 fib6_info_release(f6i);
1387 return NULL;
1388 }
1389 ip6_rt_copy_init(pcpu_rt, res);
1390 pcpu_rt->rt6i_flags |= RTF_PCPU;
1391 return pcpu_rt;
1392 }
1393
1394 /* It should be called with rcu_read_lock() acquired */
1395 static struct rt6_info *rt6_get_pcpu_route(const struct fib6_result *res)
1396 {
1397 struct rt6_info *pcpu_rt;
1398
1399 pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu);
1400
1401 return pcpu_rt;
1402 }
1403
1404 static struct rt6_info *rt6_make_pcpu_route(struct net *net,
1405 const struct fib6_result *res)
1406 {
1407 struct rt6_info *pcpu_rt, *prev, **p;
1408
1409 pcpu_rt = ip6_rt_pcpu_alloc(res);
1410 if (!pcpu_rt)
1411 return NULL;
1412
1413 p = this_cpu_ptr(res->nh->rt6i_pcpu);
1414 prev = cmpxchg(p, NULL, pcpu_rt);
1415 BUG_ON(prev);
1416
1417 if (res->f6i->fib6_destroying) {
1418 struct fib6_info *from;
1419
1420 from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
1421 fib6_info_release(from);
1422 }
1423
1424 return pcpu_rt;
1425 }
1426
1427 /* exception hash table implementation
1428 */
1429 static DEFINE_SPINLOCK(rt6_exception_lock);
1430
1431 /* Remove rt6_ex from hash table and free the memory
1432 * Caller must hold rt6_exception_lock
1433 */
1434 static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
1435 struct rt6_exception *rt6_ex)
1436 {
1437 struct fib6_info *from;
1438 struct net *net;
1439
1440 if (!bucket || !rt6_ex)
1441 return;
1442
1443 net = dev_net(rt6_ex->rt6i->dst.dev);
1444 net->ipv6.rt6_stats->fib_rt_cache--;
1445
1446 /* purge completely the exception to allow releasing the held resources:
1447 * some [sk] cache may keep the dst around for unlimited time
1448 */
1449 from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL);
1450 fib6_info_release(from);
1451 dst_dev_put(&rt6_ex->rt6i->dst);
1452
1453 hlist_del_rcu(&rt6_ex->hlist);
1454 dst_release(&rt6_ex->rt6i->dst);
1455 kfree_rcu(rt6_ex, rcu);
1456 WARN_ON_ONCE(!bucket->depth);
1457 bucket->depth--;
1458 }
1459
1460 /* Remove oldest rt6_ex in bucket and free the memory
1461 * Caller must hold rt6_exception_lock
1462 */
1463 static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
1464 {
1465 struct rt6_exception *rt6_ex, *oldest = NULL;
1466
1467 if (!bucket)
1468 return;
1469
1470 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1471 if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
1472 oldest = rt6_ex;
1473 }
1474 rt6_remove_exception(bucket, oldest);
1475 }
1476
1477 static u32 rt6_exception_hash(const struct in6_addr *dst,
1478 const struct in6_addr *src)
1479 {
1480 static u32 seed __read_mostly;
1481 u32 val;
1482
1483 net_get_random_once(&seed, sizeof(seed));
1484 val = jhash2((const u32 *)dst, sizeof(*dst)/sizeof(u32), seed);
1485
1486 #ifdef CONFIG_IPV6_SUBTREES
1487 if (src)
1488 val = jhash2((const u32 *)src, sizeof(*src)/sizeof(u32), val);
1489 #endif
1490 return hash_32(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
1491 }
1492
1493 /* Helper function to find the cached rt in the hash table
1494 * and update bucket pointer to point to the bucket for this
1495 * (daddr, saddr) pair
1496 * Caller must hold rt6_exception_lock
1497 */
1498 static struct rt6_exception *
1499 __rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
1500 const struct in6_addr *daddr,
1501 const struct in6_addr *saddr)
1502 {
1503 struct rt6_exception *rt6_ex;
1504 u32 hval;
1505
1506 if (!(*bucket) || !daddr)
1507 return NULL;
1508
1509 hval = rt6_exception_hash(daddr, saddr);
1510 *bucket += hval;
1511
1512 hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
1513 struct rt6_info *rt6 = rt6_ex->rt6i;
1514 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1515
1516 #ifdef CONFIG_IPV6_SUBTREES
1517 if (matched && saddr)
1518 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1519 #endif
1520 if (matched)
1521 return rt6_ex;
1522 }
1523 return NULL;
1524 }
1525
1526 /* Helper function to find the cached rt in the hash table
1527 * and update bucket pointer to point to the bucket for this
1528 * (daddr, saddr) pair
1529 * Caller must hold rcu_read_lock()
1530 */
1531 static struct rt6_exception *
1532 __rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
1533 const struct in6_addr *daddr,
1534 const struct in6_addr *saddr)
1535 {
1536 struct rt6_exception *rt6_ex;
1537 u32 hval;
1538
1539 WARN_ON_ONCE(!rcu_read_lock_held());
1540
1541 if (!(*bucket) || !daddr)
1542 return NULL;
1543
1544 hval = rt6_exception_hash(daddr, saddr);
1545 *bucket += hval;
1546
1547 hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
1548 struct rt6_info *rt6 = rt6_ex->rt6i;
1549 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1550
1551 #ifdef CONFIG_IPV6_SUBTREES
1552 if (matched && saddr)
1553 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1554 #endif
1555 if (matched)
1556 return rt6_ex;
1557 }
1558 return NULL;
1559 }
1560
1561 static unsigned int fib6_mtu(const struct fib6_result *res)
1562 {
1563 const struct fib6_nh *nh = res->nh;
1564 unsigned int mtu;
1565
1566 if (res->f6i->fib6_pmtu) {
1567 mtu = res->f6i->fib6_pmtu;
1568 } else {
1569 struct net_device *dev = nh->fib_nh_dev;
1570 struct inet6_dev *idev;
1571
1572 rcu_read_lock();
1573 idev = __in6_dev_get(dev);
1574 mtu = idev->cnf.mtu6;
1575 rcu_read_unlock();
1576 }
1577
1578 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1579
1580 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
1581 }
1582
1583 #define FIB6_EXCEPTION_BUCKET_FLUSHED 0x1UL
1584
1585 /* used when the flushed bit is not relevant, only access to the bucket
1586 * (ie., all bucket users except rt6_insert_exception);
1587 *
1588 * called under rcu lock; sometimes called with rt6_exception_lock held
1589 */
1590 static
1591 struct rt6_exception_bucket *fib6_nh_get_excptn_bucket(const struct fib6_nh *nh,
1592 spinlock_t *lock)
1593 {
1594 struct rt6_exception_bucket *bucket;
1595
1596 if (lock)
1597 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1598 lockdep_is_held(lock));
1599 else
1600 bucket = rcu_dereference(nh->rt6i_exception_bucket);
1601
1602 /* remove bucket flushed bit if set */
1603 if (bucket) {
1604 unsigned long p = (unsigned long)bucket;
1605
1606 p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED;
1607 bucket = (struct rt6_exception_bucket *)p;
1608 }
1609
1610 return bucket;
1611 }
1612
1613 static bool fib6_nh_excptn_bucket_flushed(struct rt6_exception_bucket *bucket)
1614 {
1615 unsigned long p = (unsigned long)bucket;
1616
1617 return !!(p & FIB6_EXCEPTION_BUCKET_FLUSHED);
1618 }
1619
1620 /* called with rt6_exception_lock held */
1621 static void fib6_nh_excptn_bucket_set_flushed(struct fib6_nh *nh,
1622 spinlock_t *lock)
1623 {
1624 struct rt6_exception_bucket *bucket;
1625 unsigned long p;
1626
1627 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1628 lockdep_is_held(lock));
1629
1630 p = (unsigned long)bucket;
1631 p |= FIB6_EXCEPTION_BUCKET_FLUSHED;
1632 bucket = (struct rt6_exception_bucket *)p;
1633 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1634 }
1635
1636 static int rt6_insert_exception(struct rt6_info *nrt,
1637 const struct fib6_result *res)
1638 {
1639 struct net *net = dev_net(nrt->dst.dev);
1640 struct rt6_exception_bucket *bucket;
1641 struct fib6_info *f6i = res->f6i;
1642 struct in6_addr *src_key = NULL;
1643 struct rt6_exception *rt6_ex;
1644 struct fib6_nh *nh = res->nh;
1645 int err = 0;
1646
1647 spin_lock_bh(&rt6_exception_lock);
1648
1649 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1650 lockdep_is_held(&rt6_exception_lock));
1651 if (!bucket) {
1652 bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
1653 GFP_ATOMIC);
1654 if (!bucket) {
1655 err = -ENOMEM;
1656 goto out;
1657 }
1658 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1659 } else if (fib6_nh_excptn_bucket_flushed(bucket)) {
1660 err = -EINVAL;
1661 goto out;
1662 }
1663
1664 #ifdef CONFIG_IPV6_SUBTREES
1665 /* fib6_src.plen != 0 indicates f6i is in subtree
1666 * and exception table is indexed by a hash of
1667 * both fib6_dst and fib6_src.
1668 * Otherwise, the exception table is indexed by
1669 * a hash of only fib6_dst.
1670 */
1671 if (f6i->fib6_src.plen)
1672 src_key = &nrt->rt6i_src.addr;
1673 #endif
1674 /* rt6_mtu_change() might lower mtu on f6i.
1675 * Only insert this exception route if its mtu
1676 * is less than f6i's mtu value.
1677 */
1678 if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(res)) {
1679 err = -EINVAL;
1680 goto out;
1681 }
1682
1683 rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
1684 src_key);
1685 if (rt6_ex)
1686 rt6_remove_exception(bucket, rt6_ex);
1687
1688 rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
1689 if (!rt6_ex) {
1690 err = -ENOMEM;
1691 goto out;
1692 }
1693 rt6_ex->rt6i = nrt;
1694 rt6_ex->stamp = jiffies;
1695 hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
1696 bucket->depth++;
1697 net->ipv6.rt6_stats->fib_rt_cache++;
1698
1699 if (bucket->depth > FIB6_MAX_DEPTH)
1700 rt6_exception_remove_oldest(bucket);
1701
1702 out:
1703 spin_unlock_bh(&rt6_exception_lock);
1704
1705 /* Update fn->fn_sernum to invalidate all cached dst */
1706 if (!err) {
1707 spin_lock_bh(&f6i->fib6_table->tb6_lock);
1708 fib6_update_sernum(net, f6i);
1709 spin_unlock_bh(&f6i->fib6_table->tb6_lock);
1710 fib6_force_start_gc(net);
1711 }
1712
1713 return err;
1714 }
1715
1716 static void fib6_nh_flush_exceptions(struct fib6_nh *nh, struct fib6_info *from)
1717 {
1718 struct rt6_exception_bucket *bucket;
1719 struct rt6_exception *rt6_ex;
1720 struct hlist_node *tmp;
1721 int i;
1722
1723 spin_lock_bh(&rt6_exception_lock);
1724
1725 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1726 if (!bucket)
1727 goto out;
1728
1729 /* Prevent rt6_insert_exception() to recreate the bucket list */
1730 if (!from)
1731 fib6_nh_excptn_bucket_set_flushed(nh, &rt6_exception_lock);
1732
1733 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1734 hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist) {
1735 if (!from ||
1736 rcu_access_pointer(rt6_ex->rt6i->from) == from)
1737 rt6_remove_exception(bucket, rt6_ex);
1738 }
1739 WARN_ON_ONCE(!from && bucket->depth);
1740 bucket++;
1741 }
1742 out:
1743 spin_unlock_bh(&rt6_exception_lock);
1744 }
1745
1746 static int rt6_nh_flush_exceptions(struct fib6_nh *nh, void *arg)
1747 {
1748 struct fib6_info *f6i = arg;
1749
1750 fib6_nh_flush_exceptions(nh, f6i);
1751
1752 return 0;
1753 }
1754
1755 void rt6_flush_exceptions(struct fib6_info *f6i)
1756 {
1757 if (f6i->nh)
1758 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions,
1759 f6i);
1760 else
1761 fib6_nh_flush_exceptions(f6i->fib6_nh, f6i);
1762 }
1763
1764 /* Find cached rt in the hash table inside passed in rt
1765 * Caller has to hold rcu_read_lock()
1766 */
1767 static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
1768 const struct in6_addr *daddr,
1769 const struct in6_addr *saddr)
1770 {
1771 const struct in6_addr *src_key = NULL;
1772 struct rt6_exception_bucket *bucket;
1773 struct rt6_exception *rt6_ex;
1774 struct rt6_info *ret = NULL;
1775
1776 #ifdef CONFIG_IPV6_SUBTREES
1777 /* fib6i_src.plen != 0 indicates f6i is in subtree
1778 * and exception table is indexed by a hash of
1779 * both fib6_dst and fib6_src.
1780 * However, the src addr used to create the hash
1781 * might not be exactly the passed in saddr which
1782 * is a /128 addr from the flow.
1783 * So we need to use f6i->fib6_src to redo lookup
1784 * if the passed in saddr does not find anything.
1785 * (See the logic in ip6_rt_cache_alloc() on how
1786 * rt->rt6i_src is updated.)
1787 */
1788 if (res->f6i->fib6_src.plen)
1789 src_key = saddr;
1790 find_ex:
1791 #endif
1792 bucket = fib6_nh_get_excptn_bucket(res->nh, NULL);
1793 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
1794
1795 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
1796 ret = rt6_ex->rt6i;
1797
1798 #ifdef CONFIG_IPV6_SUBTREES
1799 /* Use fib6_src as src_key and redo lookup */
1800 if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) {
1801 src_key = &res->f6i->fib6_src.addr;
1802 goto find_ex;
1803 }
1804 #endif
1805
1806 return ret;
1807 }
1808
1809 /* Remove the passed in cached rt from the hash table that contains it */
1810 static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen,
1811 const struct rt6_info *rt)
1812 {
1813 const struct in6_addr *src_key = NULL;
1814 struct rt6_exception_bucket *bucket;
1815 struct rt6_exception *rt6_ex;
1816 int err;
1817
1818 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
1819 return -ENOENT;
1820
1821 spin_lock_bh(&rt6_exception_lock);
1822 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1823
1824 #ifdef CONFIG_IPV6_SUBTREES
1825 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1826 * and exception table is indexed by a hash of
1827 * both rt6i_dst and rt6i_src.
1828 * Otherwise, the exception table is indexed by
1829 * a hash of only rt6i_dst.
1830 */
1831 if (plen)
1832 src_key = &rt->rt6i_src.addr;
1833 #endif
1834 rt6_ex = __rt6_find_exception_spinlock(&bucket,
1835 &rt->rt6i_dst.addr,
1836 src_key);
1837 if (rt6_ex) {
1838 rt6_remove_exception(bucket, rt6_ex);
1839 err = 0;
1840 } else {
1841 err = -ENOENT;
1842 }
1843
1844 spin_unlock_bh(&rt6_exception_lock);
1845 return err;
1846 }
1847
1848 struct fib6_nh_excptn_arg {
1849 struct rt6_info *rt;
1850 int plen;
1851 };
1852
1853 static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg)
1854 {
1855 struct fib6_nh_excptn_arg *arg = _arg;
1856 int err;
1857
1858 err = fib6_nh_remove_exception(nh, arg->plen, arg->rt);
1859 if (err == 0)
1860 return 1;
1861
1862 return 0;
1863 }
1864
1865 static int rt6_remove_exception_rt(struct rt6_info *rt)
1866 {
1867 struct fib6_info *from;
1868
1869 from = rcu_dereference(rt->from);
1870 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1871 return -EINVAL;
1872
1873 if (from->nh) {
1874 struct fib6_nh_excptn_arg arg = {
1875 .rt = rt,
1876 .plen = from->fib6_src.plen
1877 };
1878 int rc;
1879
1880 /* rc = 1 means an entry was found */
1881 rc = nexthop_for_each_fib6_nh(from->nh,
1882 rt6_nh_remove_exception_rt,
1883 &arg);
1884 return rc ? 0 : -ENOENT;
1885 }
1886
1887 return fib6_nh_remove_exception(from->fib6_nh,
1888 from->fib6_src.plen, rt);
1889 }
1890
1891 /* Find rt6_ex which contains the passed in rt cache and
1892 * refresh its stamp
1893 */
1894 static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen,
1895 const struct rt6_info *rt)
1896 {
1897 const struct in6_addr *src_key = NULL;
1898 struct rt6_exception_bucket *bucket;
1899 struct rt6_exception *rt6_ex;
1900
1901 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
1902 #ifdef CONFIG_IPV6_SUBTREES
1903 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1904 * and exception table is indexed by a hash of
1905 * both rt6i_dst and rt6i_src.
1906 * Otherwise, the exception table is indexed by
1907 * a hash of only rt6i_dst.
1908 */
1909 if (plen)
1910 src_key = &rt->rt6i_src.addr;
1911 #endif
1912 rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key);
1913 if (rt6_ex)
1914 rt6_ex->stamp = jiffies;
1915 }
1916
1917 struct fib6_nh_match_arg {
1918 const struct net_device *dev;
1919 const struct in6_addr *gw;
1920 struct fib6_nh *match;
1921 };
1922
1923 /* determine if fib6_nh has given device and gateway */
1924 static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg)
1925 {
1926 struct fib6_nh_match_arg *arg = _arg;
1927
1928 if (arg->dev != nh->fib_nh_dev ||
1929 (arg->gw && !nh->fib_nh_gw_family) ||
1930 (!arg->gw && nh->fib_nh_gw_family) ||
1931 (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6)))
1932 return 0;
1933
1934 arg->match = nh;
1935
1936 /* found a match, break the loop */
1937 return 1;
1938 }
1939
1940 static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
1941 {
1942 struct fib6_info *from;
1943 struct fib6_nh *fib6_nh;
1944
1945 rcu_read_lock();
1946
1947 from = rcu_dereference(rt->from);
1948 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1949 goto unlock;
1950
1951 if (from->nh) {
1952 struct fib6_nh_match_arg arg = {
1953 .dev = rt->dst.dev,
1954 .gw = &rt->rt6i_gateway,
1955 };
1956
1957 nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg);
1958
1959 if (!arg.match)
1960 goto unlock;
1961 fib6_nh = arg.match;
1962 } else {
1963 fib6_nh = from->fib6_nh;
1964 }
1965 fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt);
1966 unlock:
1967 rcu_read_unlock();
1968 }
1969
1970 static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
1971 struct rt6_info *rt, int mtu)
1972 {
1973 /* If the new MTU is lower than the route PMTU, this new MTU will be the
1974 * lowest MTU in the path: always allow updating the route PMTU to
1975 * reflect PMTU decreases.
1976 *
1977 * If the new MTU is higher, and the route PMTU is equal to the local
1978 * MTU, this means the old MTU is the lowest in the path, so allow
1979 * updating it: if other nodes now have lower MTUs, PMTU discovery will
1980 * handle this.
1981 */
1982
1983 if (dst_mtu(&rt->dst) >= mtu)
1984 return true;
1985
1986 if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
1987 return true;
1988
1989 return false;
1990 }
1991
1992 static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
1993 const struct fib6_nh *nh, int mtu)
1994 {
1995 struct rt6_exception_bucket *bucket;
1996 struct rt6_exception *rt6_ex;
1997 int i;
1998
1999 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2000 if (!bucket)
2001 return;
2002
2003 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2004 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
2005 struct rt6_info *entry = rt6_ex->rt6i;
2006
2007 /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
2008 * route), the metrics of its rt->from have already
2009 * been updated.
2010 */
2011 if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
2012 rt6_mtu_change_route_allowed(idev, entry, mtu))
2013 dst_metric_set(&entry->dst, RTAX_MTU, mtu);
2014 }
2015 bucket++;
2016 }
2017 }
2018
2019 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2020
2021 static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh,
2022 const struct in6_addr *gateway)
2023 {
2024 struct rt6_exception_bucket *bucket;
2025 struct rt6_exception *rt6_ex;
2026 struct hlist_node *tmp;
2027 int i;
2028
2029 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2030 return;
2031
2032 spin_lock_bh(&rt6_exception_lock);
2033 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2034 if (bucket) {
2035 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2036 hlist_for_each_entry_safe(rt6_ex, tmp,
2037 &bucket->chain, hlist) {
2038 struct rt6_info *entry = rt6_ex->rt6i;
2039
2040 if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
2041 RTF_CACHE_GATEWAY &&
2042 ipv6_addr_equal(gateway,
2043 &entry->rt6i_gateway)) {
2044 rt6_remove_exception(bucket, rt6_ex);
2045 }
2046 }
2047 bucket++;
2048 }
2049 }
2050
2051 spin_unlock_bh(&rt6_exception_lock);
2052 }
2053
2054 static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
2055 struct rt6_exception *rt6_ex,
2056 struct fib6_gc_args *gc_args,
2057 unsigned long now)
2058 {
2059 struct rt6_info *rt = rt6_ex->rt6i;
2060
2061 /* we are pruning and obsoleting aged-out and non gateway exceptions
2062 * even if others have still references to them, so that on next
2063 * dst_check() such references can be dropped.
2064 * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
2065 * expired, independently from their aging, as per RFC 8201 section 4
2066 */
2067 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
2068 if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
2069 RT6_TRACE("aging clone %p\n", rt);
2070 rt6_remove_exception(bucket, rt6_ex);
2071 return;
2072 }
2073 } else if (time_after(jiffies, rt->dst.expires)) {
2074 RT6_TRACE("purging expired route %p\n", rt);
2075 rt6_remove_exception(bucket, rt6_ex);
2076 return;
2077 }
2078
2079 if (rt->rt6i_flags & RTF_GATEWAY) {
2080 struct neighbour *neigh;
2081 __u8 neigh_flags = 0;
2082
2083 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
2084 if (neigh)
2085 neigh_flags = neigh->flags;
2086
2087 if (!(neigh_flags & NTF_ROUTER)) {
2088 RT6_TRACE("purging route %p via non-router but gateway\n",
2089 rt);
2090 rt6_remove_exception(bucket, rt6_ex);
2091 return;
2092 }
2093 }
2094
2095 gc_args->more++;
2096 }
2097
2098 static void fib6_nh_age_exceptions(const struct fib6_nh *nh,
2099 struct fib6_gc_args *gc_args,
2100 unsigned long now)
2101 {
2102 struct rt6_exception_bucket *bucket;
2103 struct rt6_exception *rt6_ex;
2104 struct hlist_node *tmp;
2105 int i;
2106
2107 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2108 return;
2109
2110 rcu_read_lock_bh();
2111 spin_lock(&rt6_exception_lock);
2112 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2113 if (bucket) {
2114 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2115 hlist_for_each_entry_safe(rt6_ex, tmp,
2116 &bucket->chain, hlist) {
2117 rt6_age_examine_exception(bucket, rt6_ex,
2118 gc_args, now);
2119 }
2120 bucket++;
2121 }
2122 }
2123 spin_unlock(&rt6_exception_lock);
2124 rcu_read_unlock_bh();
2125 }
2126
2127 struct fib6_nh_age_excptn_arg {
2128 struct fib6_gc_args *gc_args;
2129 unsigned long now;
2130 };
2131
2132 static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg)
2133 {
2134 struct fib6_nh_age_excptn_arg *arg = _arg;
2135
2136 fib6_nh_age_exceptions(nh, arg->gc_args, arg->now);
2137 return 0;
2138 }
2139
2140 void rt6_age_exceptions(struct fib6_info *f6i,
2141 struct fib6_gc_args *gc_args,
2142 unsigned long now)
2143 {
2144 if (f6i->nh) {
2145 struct fib6_nh_age_excptn_arg arg = {
2146 .gc_args = gc_args,
2147 .now = now
2148 };
2149
2150 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions,
2151 &arg);
2152 } else {
2153 fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now);
2154 }
2155 }
2156
2157 /* must be called with rcu lock held */
2158 int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif,
2159 struct flowi6 *fl6, struct fib6_result *res, int strict)
2160 {
2161 struct fib6_node *fn, *saved_fn;
2162
2163 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2164 saved_fn = fn;
2165
2166 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2167 oif = 0;
2168
2169 redo_rt6_select:
2170 rt6_select(net, fn, oif, res, strict);
2171 if (res->f6i == net->ipv6.fib6_null_entry) {
2172 fn = fib6_backtrack(fn, &fl6->saddr);
2173 if (fn)
2174 goto redo_rt6_select;
2175 else if (strict & RT6_LOOKUP_F_REACHABLE) {
2176 /* also consider unreachable route */
2177 strict &= ~RT6_LOOKUP_F_REACHABLE;
2178 fn = saved_fn;
2179 goto redo_rt6_select;
2180 }
2181 }
2182
2183 trace_fib6_table_lookup(net, res, table, fl6);
2184
2185 return 0;
2186 }
2187
2188 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
2189 int oif, struct flowi6 *fl6,
2190 const struct sk_buff *skb, int flags)
2191 {
2192 struct fib6_result res = {};
2193 struct rt6_info *rt = NULL;
2194 int strict = 0;
2195
2196 WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) &&
2197 !rcu_read_lock_held());
2198
2199 strict |= flags & RT6_LOOKUP_F_IFACE;
2200 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
2201 if (net->ipv6.devconf_all->forwarding == 0)
2202 strict |= RT6_LOOKUP_F_REACHABLE;
2203
2204 rcu_read_lock();
2205
2206 fib6_table_lookup(net, table, oif, fl6, &res, strict);
2207 if (res.f6i == net->ipv6.fib6_null_entry)
2208 goto out;
2209
2210 fib6_select_path(net, &res, fl6, oif, false, skb, strict);
2211
2212 /*Search through exception table */
2213 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
2214 if (rt) {
2215 goto out;
2216 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
2217 !res.nh->fib_nh_gw_family)) {
2218 /* Create a RTF_CACHE clone which will not be
2219 * owned by the fib6 tree. It is for the special case where
2220 * the daddr in the skb during the neighbor look-up is different
2221 * from the fl6->daddr used to look-up route here.
2222 */
2223 rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL);
2224
2225 if (rt) {
2226 /* 1 refcnt is taken during ip6_rt_cache_alloc().
2227 * As rt6_uncached_list_add() does not consume refcnt,
2228 * this refcnt is always returned to the caller even
2229 * if caller sets RT6_LOOKUP_F_DST_NOREF flag.
2230 */
2231 rt6_uncached_list_add(rt);
2232 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
2233 rcu_read_unlock();
2234
2235 return rt;
2236 }
2237 } else {
2238 /* Get a percpu copy */
2239 local_bh_disable();
2240 rt = rt6_get_pcpu_route(&res);
2241
2242 if (!rt)
2243 rt = rt6_make_pcpu_route(net, &res);
2244
2245 local_bh_enable();
2246 }
2247 out:
2248 if (!rt)
2249 rt = net->ipv6.ip6_null_entry;
2250 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
2251 ip6_hold_safe(net, &rt);
2252 rcu_read_unlock();
2253
2254 return rt;
2255 }
2256 EXPORT_SYMBOL_GPL(ip6_pol_route);
2257
2258 static struct rt6_info *ip6_pol_route_input(struct net *net,
2259 struct fib6_table *table,
2260 struct flowi6 *fl6,
2261 const struct sk_buff *skb,
2262 int flags)
2263 {
2264 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags);
2265 }
2266
2267 struct dst_entry *ip6_route_input_lookup(struct net *net,
2268 struct net_device *dev,
2269 struct flowi6 *fl6,
2270 const struct sk_buff *skb,
2271 int flags)
2272 {
2273 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
2274 flags |= RT6_LOOKUP_F_IFACE;
2275
2276 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input);
2277 }
2278 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
2279
2280 static void ip6_multipath_l3_keys(const struct sk_buff *skb,
2281 struct flow_keys *keys,
2282 struct flow_keys *flkeys)
2283 {
2284 const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
2285 const struct ipv6hdr *key_iph = outer_iph;
2286 struct flow_keys *_flkeys = flkeys;
2287 const struct ipv6hdr *inner_iph;
2288 const struct icmp6hdr *icmph;
2289 struct ipv6hdr _inner_iph;
2290 struct icmp6hdr _icmph;
2291
2292 if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6))
2293 goto out;
2294
2295 icmph = skb_header_pointer(skb, skb_transport_offset(skb),
2296 sizeof(_icmph), &_icmph);
2297 if (!icmph)
2298 goto out;
2299
2300 if (!icmpv6_is_err(icmph->icmp6_type))
2301 goto out;
2302
2303 inner_iph = skb_header_pointer(skb,
2304 skb_transport_offset(skb) + sizeof(*icmph),
2305 sizeof(_inner_iph), &_inner_iph);
2306 if (!inner_iph)
2307 goto out;
2308
2309 key_iph = inner_iph;
2310 _flkeys = NULL;
2311 out:
2312 if (_flkeys) {
2313 keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src;
2314 keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst;
2315 keys->tags.flow_label = _flkeys->tags.flow_label;
2316 keys->basic.ip_proto = _flkeys->basic.ip_proto;
2317 } else {
2318 keys->addrs.v6addrs.src = key_iph->saddr;
2319 keys->addrs.v6addrs.dst = key_iph->daddr;
2320 keys->tags.flow_label = ip6_flowlabel(key_iph);
2321 keys->basic.ip_proto = key_iph->nexthdr;
2322 }
2323 }
2324
2325 /* if skb is set it will be used and fl6 can be NULL */
2326 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
2327 const struct sk_buff *skb, struct flow_keys *flkeys)
2328 {
2329 struct flow_keys hash_keys;
2330 u32 mhash;
2331
2332 switch (ip6_multipath_hash_policy(net)) {
2333 case 0:
2334 memset(&hash_keys, 0, sizeof(hash_keys));
2335 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2336 if (skb) {
2337 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2338 } else {
2339 hash_keys.addrs.v6addrs.src = fl6->saddr;
2340 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2341 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2342 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2343 }
2344 break;
2345 case 1:
2346 if (skb) {
2347 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
2348 struct flow_keys keys;
2349
2350 /* short-circuit if we already have L4 hash present */
2351 if (skb->l4_hash)
2352 return skb_get_hash_raw(skb) >> 1;
2353
2354 memset(&hash_keys, 0, sizeof(hash_keys));
2355
2356 if (!flkeys) {
2357 skb_flow_dissect_flow_keys(skb, &keys, flag);
2358 flkeys = &keys;
2359 }
2360 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2361 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2362 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2363 hash_keys.ports.src = flkeys->ports.src;
2364 hash_keys.ports.dst = flkeys->ports.dst;
2365 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2366 } else {
2367 memset(&hash_keys, 0, sizeof(hash_keys));
2368 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2369 hash_keys.addrs.v6addrs.src = fl6->saddr;
2370 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2371 hash_keys.ports.src = fl6->fl6_sport;
2372 hash_keys.ports.dst = fl6->fl6_dport;
2373 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2374 }
2375 break;
2376 case 2:
2377 memset(&hash_keys, 0, sizeof(hash_keys));
2378 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2379 if (skb) {
2380 struct flow_keys keys;
2381
2382 if (!flkeys) {
2383 skb_flow_dissect_flow_keys(skb, &keys, 0);
2384 flkeys = &keys;
2385 }
2386
2387 /* Inner can be v4 or v6 */
2388 if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
2389 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
2390 hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src;
2391 hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst;
2392 } else if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
2393 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2394 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2395 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2396 hash_keys.tags.flow_label = flkeys->tags.flow_label;
2397 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2398 } else {
2399 /* Same as case 0 */
2400 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2401 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2402 }
2403 } else {
2404 /* Same as case 0 */
2405 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2406 hash_keys.addrs.v6addrs.src = fl6->saddr;
2407 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2408 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2409 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2410 }
2411 break;
2412 }
2413 mhash = flow_hash_from_keys(&hash_keys);
2414
2415 return mhash >> 1;
2416 }
2417
2418 /* Called with rcu held */
2419 void ip6_route_input(struct sk_buff *skb)
2420 {
2421 const struct ipv6hdr *iph = ipv6_hdr(skb);
2422 struct net *net = dev_net(skb->dev);
2423 int flags = RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_DST_NOREF;
2424 struct ip_tunnel_info *tun_info;
2425 struct flowi6 fl6 = {
2426 .flowi6_iif = skb->dev->ifindex,
2427 .daddr = iph->daddr,
2428 .saddr = iph->saddr,
2429 .flowlabel = ip6_flowinfo(iph),
2430 .flowi6_mark = skb->mark,
2431 .flowi6_proto = iph->nexthdr,
2432 };
2433 struct flow_keys *flkeys = NULL, _flkeys;
2434
2435 tun_info = skb_tunnel_info(skb);
2436 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
2437 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
2438
2439 if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys))
2440 flkeys = &_flkeys;
2441
2442 if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6))
2443 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys);
2444 skb_dst_drop(skb);
2445 skb_dst_set_noref(skb, ip6_route_input_lookup(net, skb->dev,
2446 &fl6, skb, flags));
2447 }
2448
2449 static struct rt6_info *ip6_pol_route_output(struct net *net,
2450 struct fib6_table *table,
2451 struct flowi6 *fl6,
2452 const struct sk_buff *skb,
2453 int flags)
2454 {
2455 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags);
2456 }
2457
2458 struct dst_entry *ip6_route_output_flags_noref(struct net *net,
2459 const struct sock *sk,
2460 struct flowi6 *fl6, int flags)
2461 {
2462 bool any_src;
2463
2464 if (ipv6_addr_type(&fl6->daddr) &
2465 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
2466 struct dst_entry *dst;
2467
2468 /* This function does not take refcnt on the dst */
2469 dst = l3mdev_link_scope_lookup(net, fl6);
2470 if (dst)
2471 return dst;
2472 }
2473
2474 fl6->flowi6_iif = LOOPBACK_IFINDEX;
2475
2476 flags |= RT6_LOOKUP_F_DST_NOREF;
2477 any_src = ipv6_addr_any(&fl6->saddr);
2478 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
2479 (fl6->flowi6_oif && any_src))
2480 flags |= RT6_LOOKUP_F_IFACE;
2481
2482 if (!any_src)
2483 flags |= RT6_LOOKUP_F_HAS_SADDR;
2484 else if (sk)
2485 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
2486
2487 return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
2488 }
2489 EXPORT_SYMBOL_GPL(ip6_route_output_flags_noref);
2490
2491 struct dst_entry *ip6_route_output_flags(struct net *net,
2492 const struct sock *sk,
2493 struct flowi6 *fl6,
2494 int flags)
2495 {
2496 struct dst_entry *dst;
2497 struct rt6_info *rt6;
2498
2499 rcu_read_lock();
2500 dst = ip6_route_output_flags_noref(net, sk, fl6, flags);
2501 rt6 = (struct rt6_info *)dst;
2502 /* For dst cached in uncached_list, refcnt is already taken. */
2503 if (list_empty(&rt6->rt6i_uncached) && !dst_hold_safe(dst)) {
2504 dst = &net->ipv6.ip6_null_entry->dst;
2505 dst_hold(dst);
2506 }
2507 rcu_read_unlock();
2508
2509 return dst;
2510 }
2511 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
2512
2513 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2514 {
2515 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
2516 struct net_device *loopback_dev = net->loopback_dev;
2517 struct dst_entry *new = NULL;
2518
2519 rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, 1,
2520 DST_OBSOLETE_DEAD, 0);
2521 if (rt) {
2522 rt6_info_init(rt);
2523 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
2524
2525 new = &rt->dst;
2526 new->__use = 1;
2527 new->input = dst_discard;
2528 new->output = dst_discard_out;
2529
2530 dst_copy_metrics(new, &ort->dst);
2531
2532 rt->rt6i_idev = in6_dev_get(loopback_dev);
2533 rt->rt6i_gateway = ort->rt6i_gateway;
2534 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
2535
2536 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
2537 #ifdef CONFIG_IPV6_SUBTREES
2538 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
2539 #endif
2540 }
2541
2542 dst_release(dst_orig);
2543 return new ? new : ERR_PTR(-ENOMEM);
2544 }
2545
2546 /*
2547 * Destination cache support functions
2548 */
2549
2550 static bool fib6_check(struct fib6_info *f6i, u32 cookie)
2551 {
2552 u32 rt_cookie = 0;
2553
2554 if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
2555 return false;
2556
2557 if (fib6_check_expired(f6i))
2558 return false;
2559
2560 return true;
2561 }
2562
2563 static struct dst_entry *rt6_check(struct rt6_info *rt,
2564 struct fib6_info *from,
2565 u32 cookie)
2566 {
2567 u32 rt_cookie = 0;
2568
2569 if (!from || !fib6_get_cookie_safe(from, &rt_cookie) ||
2570 rt_cookie != cookie)
2571 return NULL;
2572
2573 if (rt6_check_expired(rt))
2574 return NULL;
2575
2576 return &rt->dst;
2577 }
2578
2579 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
2580 struct fib6_info *from,
2581 u32 cookie)
2582 {
2583 if (!__rt6_check_expired(rt) &&
2584 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
2585 fib6_check(from, cookie))
2586 return &rt->dst;
2587 else
2588 return NULL;
2589 }
2590
2591 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
2592 {
2593 struct dst_entry *dst_ret;
2594 struct fib6_info *from;
2595 struct rt6_info *rt;
2596
2597 rt = container_of(dst, struct rt6_info, dst);
2598
2599 rcu_read_lock();
2600
2601 /* All IPV6 dsts are created with ->obsolete set to the value
2602 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
2603 * into this function always.
2604 */
2605
2606 from = rcu_dereference(rt->from);
2607
2608 if (from && (rt->rt6i_flags & RTF_PCPU ||
2609 unlikely(!list_empty(&rt->rt6i_uncached))))
2610 dst_ret = rt6_dst_from_check(rt, from, cookie);
2611 else
2612 dst_ret = rt6_check(rt, from, cookie);
2613
2614 rcu_read_unlock();
2615
2616 return dst_ret;
2617 }
2618
2619 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
2620 {
2621 struct rt6_info *rt = (struct rt6_info *) dst;
2622
2623 if (rt) {
2624 if (rt->rt6i_flags & RTF_CACHE) {
2625 rcu_read_lock();
2626 if (rt6_check_expired(rt)) {
2627 rt6_remove_exception_rt(rt);
2628 dst = NULL;
2629 }
2630 rcu_read_unlock();
2631 } else {
2632 dst_release(dst);
2633 dst = NULL;
2634 }
2635 }
2636 return dst;
2637 }
2638
2639 static void ip6_link_failure(struct sk_buff *skb)
2640 {
2641 struct rt6_info *rt;
2642
2643 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
2644
2645 rt = (struct rt6_info *) skb_dst(skb);
2646 if (rt) {
2647 rcu_read_lock();
2648 if (rt->rt6i_flags & RTF_CACHE) {
2649 rt6_remove_exception_rt(rt);
2650 } else {
2651 struct fib6_info *from;
2652 struct fib6_node *fn;
2653
2654 from = rcu_dereference(rt->from);
2655 if (from) {
2656 fn = rcu_dereference(from->fib6_node);
2657 if (fn && (rt->rt6i_flags & RTF_DEFAULT))
2658 fn->fn_sernum = -1;
2659 }
2660 }
2661 rcu_read_unlock();
2662 }
2663 }
2664
2665 static void rt6_update_expires(struct rt6_info *rt0, int timeout)
2666 {
2667 if (!(rt0->rt6i_flags & RTF_EXPIRES)) {
2668 struct fib6_info *from;
2669
2670 rcu_read_lock();
2671 from = rcu_dereference(rt0->from);
2672 if (from)
2673 rt0->dst.expires = from->expires;
2674 rcu_read_unlock();
2675 }
2676
2677 dst_set_expires(&rt0->dst, timeout);
2678 rt0->rt6i_flags |= RTF_EXPIRES;
2679 }
2680
2681 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
2682 {
2683 struct net *net = dev_net(rt->dst.dev);
2684
2685 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
2686 rt->rt6i_flags |= RTF_MODIFIED;
2687 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
2688 }
2689
2690 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
2691 {
2692 return !(rt->rt6i_flags & RTF_CACHE) &&
2693 (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from));
2694 }
2695
2696 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
2697 const struct ipv6hdr *iph, u32 mtu,
2698 bool confirm_neigh)
2699 {
2700 const struct in6_addr *daddr, *saddr;
2701 struct rt6_info *rt6 = (struct rt6_info *)dst;
2702
2703 if (dst_metric_locked(dst, RTAX_MTU))
2704 return;
2705
2706 if (iph) {
2707 daddr = &iph->daddr;
2708 saddr = &iph->saddr;
2709 } else if (sk) {
2710 daddr = &sk->sk_v6_daddr;
2711 saddr = &inet6_sk(sk)->saddr;
2712 } else {
2713 daddr = NULL;
2714 saddr = NULL;
2715 }
2716
2717 if (confirm_neigh)
2718 dst_confirm_neigh(dst, daddr);
2719
2720 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
2721 if (mtu >= dst_mtu(dst))
2722 return;
2723
2724 if (!rt6_cache_allowed_for_pmtu(rt6)) {
2725 rt6_do_update_pmtu(rt6, mtu);
2726 /* update rt6_ex->stamp for cache */
2727 if (rt6->rt6i_flags & RTF_CACHE)
2728 rt6_update_exception_stamp_rt(rt6);
2729 } else if (daddr) {
2730 struct fib6_result res = {};
2731 struct rt6_info *nrt6;
2732
2733 rcu_read_lock();
2734 res.f6i = rcu_dereference(rt6->from);
2735 if (!res.f6i)
2736 goto out_unlock;
2737
2738 res.fib6_flags = res.f6i->fib6_flags;
2739 res.fib6_type = res.f6i->fib6_type;
2740
2741 if (res.f6i->nh) {
2742 struct fib6_nh_match_arg arg = {
2743 .dev = dst->dev,
2744 .gw = &rt6->rt6i_gateway,
2745 };
2746
2747 nexthop_for_each_fib6_nh(res.f6i->nh,
2748 fib6_nh_find_match, &arg);
2749
2750 /* fib6_info uses a nexthop that does not have fib6_nh
2751 * using the dst->dev + gw. Should be impossible.
2752 */
2753 if (!arg.match)
2754 goto out_unlock;
2755
2756 res.nh = arg.match;
2757 } else {
2758 res.nh = res.f6i->fib6_nh;
2759 }
2760
2761 nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr);
2762 if (nrt6) {
2763 rt6_do_update_pmtu(nrt6, mtu);
2764 if (rt6_insert_exception(nrt6, &res))
2765 dst_release_immediate(&nrt6->dst);
2766 }
2767 out_unlock:
2768 rcu_read_unlock();
2769 }
2770 }
2771
2772 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
2773 struct sk_buff *skb, u32 mtu,
2774 bool confirm_neigh)
2775 {
2776 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu,
2777 confirm_neigh);
2778 }
2779
2780 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
2781 int oif, u32 mark, kuid_t uid)
2782 {
2783 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2784 struct dst_entry *dst;
2785 struct flowi6 fl6 = {
2786 .flowi6_oif = oif,
2787 .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark),
2788 .daddr = iph->daddr,
2789 .saddr = iph->saddr,
2790 .flowlabel = ip6_flowinfo(iph),
2791 .flowi6_uid = uid,
2792 };
2793
2794 dst = ip6_route_output(net, NULL, &fl6);
2795 if (!dst->error)
2796 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu), true);
2797 dst_release(dst);
2798 }
2799 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
2800
2801 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
2802 {
2803 int oif = sk->sk_bound_dev_if;
2804 struct dst_entry *dst;
2805
2806 if (!oif && skb->dev)
2807 oif = l3mdev_master_ifindex(skb->dev);
2808
2809 ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
2810
2811 dst = __sk_dst_get(sk);
2812 if (!dst || !dst->obsolete ||
2813 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
2814 return;
2815
2816 bh_lock_sock(sk);
2817 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
2818 ip6_datagram_dst_update(sk, false);
2819 bh_unlock_sock(sk);
2820 }
2821 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
2822
2823 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
2824 const struct flowi6 *fl6)
2825 {
2826 #ifdef CONFIG_IPV6_SUBTREES
2827 struct ipv6_pinfo *np = inet6_sk(sk);
2828 #endif
2829
2830 ip6_dst_store(sk, dst,
2831 ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr) ?
2832 &sk->sk_v6_daddr : NULL,
2833 #ifdef CONFIG_IPV6_SUBTREES
2834 ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
2835 &np->saddr :
2836 #endif
2837 NULL);
2838 }
2839
2840 static bool ip6_redirect_nh_match(const struct fib6_result *res,
2841 struct flowi6 *fl6,
2842 const struct in6_addr *gw,
2843 struct rt6_info **ret)
2844 {
2845 const struct fib6_nh *nh = res->nh;
2846
2847 if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
2848 fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
2849 return false;
2850
2851 /* rt_cache's gateway might be different from its 'parent'
2852 * in the case of an ip redirect.
2853 * So we keep searching in the exception table if the gateway
2854 * is different.
2855 */
2856 if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
2857 struct rt6_info *rt_cache;
2858
2859 rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr);
2860 if (rt_cache &&
2861 ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
2862 *ret = rt_cache;
2863 return true;
2864 }
2865 return false;
2866 }
2867 return true;
2868 }
2869
2870 struct fib6_nh_rd_arg {
2871 struct fib6_result *res;
2872 struct flowi6 *fl6;
2873 const struct in6_addr *gw;
2874 struct rt6_info **ret;
2875 };
2876
2877 static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg)
2878 {
2879 struct fib6_nh_rd_arg *arg = _arg;
2880
2881 arg->res->nh = nh;
2882 return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret);
2883 }
2884
2885 /* Handle redirects */
2886 struct ip6rd_flowi {
2887 struct flowi6 fl6;
2888 struct in6_addr gateway;
2889 };
2890
2891 static struct rt6_info *__ip6_route_redirect(struct net *net,
2892 struct fib6_table *table,
2893 struct flowi6 *fl6,
2894 const struct sk_buff *skb,
2895 int flags)
2896 {
2897 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
2898 struct rt6_info *ret = NULL;
2899 struct fib6_result res = {};
2900 struct fib6_nh_rd_arg arg = {
2901 .res = &res,
2902 .fl6 = fl6,
2903 .gw = &rdfl->gateway,
2904 .ret = &ret
2905 };
2906 struct fib6_info *rt;
2907 struct fib6_node *fn;
2908
2909 /* l3mdev_update_flow overrides oif if the device is enslaved; in
2910 * this case we must match on the real ingress device, so reset it
2911 */
2912 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2913 fl6->flowi6_oif = skb->dev->ifindex;
2914
2915 /* Get the "current" route for this destination and
2916 * check if the redirect has come from appropriate router.
2917 *
2918 * RFC 4861 specifies that redirects should only be
2919 * accepted if they come from the nexthop to the target.
2920 * Due to the way the routes are chosen, this notion
2921 * is a bit fuzzy and one might need to check all possible
2922 * routes.
2923 */
2924
2925 rcu_read_lock();
2926 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2927 restart:
2928 for_each_fib6_node_rt_rcu(fn) {
2929 res.f6i = rt;
2930 if (fib6_check_expired(rt))
2931 continue;
2932 if (rt->fib6_flags & RTF_REJECT)
2933 break;
2934 if (unlikely(rt->nh)) {
2935 if (nexthop_is_blackhole(rt->nh))
2936 continue;
2937 /* on match, res->nh is filled in and potentially ret */
2938 if (nexthop_for_each_fib6_nh(rt->nh,
2939 fib6_nh_redirect_match,
2940 &arg))
2941 goto out;
2942 } else {
2943 res.nh = rt->fib6_nh;
2944 if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway,
2945 &ret))
2946 goto out;
2947 }
2948 }
2949
2950 if (!rt)
2951 rt = net->ipv6.fib6_null_entry;
2952 else if (rt->fib6_flags & RTF_REJECT) {
2953 ret = net->ipv6.ip6_null_entry;
2954 goto out;
2955 }
2956
2957 if (rt == net->ipv6.fib6_null_entry) {
2958 fn = fib6_backtrack(fn, &fl6->saddr);
2959 if (fn)
2960 goto restart;
2961 }
2962
2963 res.f6i = rt;
2964 res.nh = rt->fib6_nh;
2965 out:
2966 if (ret) {
2967 ip6_hold_safe(net, &ret);
2968 } else {
2969 res.fib6_flags = res.f6i->fib6_flags;
2970 res.fib6_type = res.f6i->fib6_type;
2971 ret = ip6_create_rt_rcu(&res);
2972 }
2973
2974 rcu_read_unlock();
2975
2976 trace_fib6_table_lookup(net, &res, table, fl6);
2977 return ret;
2978 };
2979
2980 static struct dst_entry *ip6_route_redirect(struct net *net,
2981 const struct flowi6 *fl6,
2982 const struct sk_buff *skb,
2983 const struct in6_addr *gateway)
2984 {
2985 int flags = RT6_LOOKUP_F_HAS_SADDR;
2986 struct ip6rd_flowi rdfl;
2987
2988 rdfl.fl6 = *fl6;
2989 rdfl.gateway = *gateway;
2990
2991 return fib6_rule_lookup(net, &rdfl.fl6, skb,
2992 flags, __ip6_route_redirect);
2993 }
2994
2995 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
2996 kuid_t uid)
2997 {
2998 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2999 struct dst_entry *dst;
3000 struct flowi6 fl6 = {
3001 .flowi6_iif = LOOPBACK_IFINDEX,
3002 .flowi6_oif = oif,
3003 .flowi6_mark = mark,
3004 .daddr = iph->daddr,
3005 .saddr = iph->saddr,
3006 .flowlabel = ip6_flowinfo(iph),
3007 .flowi6_uid = uid,
3008 };
3009
3010 dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
3011 rt6_do_redirect(dst, NULL, skb);
3012 dst_release(dst);
3013 }
3014 EXPORT_SYMBOL_GPL(ip6_redirect);
3015
3016 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
3017 {
3018 const struct ipv6hdr *iph = ipv6_hdr(skb);
3019 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
3020 struct dst_entry *dst;
3021 struct flowi6 fl6 = {
3022 .flowi6_iif = LOOPBACK_IFINDEX,
3023 .flowi6_oif = oif,
3024 .daddr = msg->dest,
3025 .saddr = iph->daddr,
3026 .flowi6_uid = sock_net_uid(net, NULL),
3027 };
3028
3029 dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
3030 rt6_do_redirect(dst, NULL, skb);
3031 dst_release(dst);
3032 }
3033
3034 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
3035 {
3036 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
3037 sk->sk_uid);
3038 }
3039 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
3040
3041 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
3042 {
3043 struct net_device *dev = dst->dev;
3044 unsigned int mtu = dst_mtu(dst);
3045 struct net *net = dev_net(dev);
3046
3047 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
3048
3049 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
3050 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
3051
3052 /*
3053 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
3054 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
3055 * IPV6_MAXPLEN is also valid and means: "any MSS,
3056 * rely only on pmtu discovery"
3057 */
3058 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
3059 mtu = IPV6_MAXPLEN;
3060 return mtu;
3061 }
3062
3063 static unsigned int ip6_mtu(const struct dst_entry *dst)
3064 {
3065 struct inet6_dev *idev;
3066 unsigned int mtu;
3067
3068 mtu = dst_metric_raw(dst, RTAX_MTU);
3069 if (mtu)
3070 goto out;
3071
3072 mtu = IPV6_MIN_MTU;
3073
3074 rcu_read_lock();
3075 idev = __in6_dev_get(dst->dev);
3076 if (idev)
3077 mtu = idev->cnf.mtu6;
3078 rcu_read_unlock();
3079
3080 out:
3081 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3082
3083 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
3084 }
3085
3086 /* MTU selection:
3087 * 1. mtu on route is locked - use it
3088 * 2. mtu from nexthop exception
3089 * 3. mtu from egress device
3090 *
3091 * based on ip6_dst_mtu_forward and exception logic of
3092 * rt6_find_cached_rt; called with rcu_read_lock
3093 */
3094 u32 ip6_mtu_from_fib6(const struct fib6_result *res,
3095 const struct in6_addr *daddr,
3096 const struct in6_addr *saddr)
3097 {
3098 const struct fib6_nh *nh = res->nh;
3099 struct fib6_info *f6i = res->f6i;
3100 struct inet6_dev *idev;
3101 struct rt6_info *rt;
3102 u32 mtu = 0;
3103
3104 if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
3105 mtu = f6i->fib6_pmtu;
3106 if (mtu)
3107 goto out;
3108 }
3109
3110 rt = rt6_find_cached_rt(res, daddr, saddr);
3111 if (unlikely(rt)) {
3112 mtu = dst_metric_raw(&rt->dst, RTAX_MTU);
3113 } else {
3114 struct net_device *dev = nh->fib_nh_dev;
3115
3116 mtu = IPV6_MIN_MTU;
3117 idev = __in6_dev_get(dev);
3118 if (idev && idev->cnf.mtu6 > mtu)
3119 mtu = idev->cnf.mtu6;
3120 }
3121
3122 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3123 out:
3124 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
3125 }
3126
3127 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
3128 struct flowi6 *fl6)
3129 {
3130 struct dst_entry *dst;
3131 struct rt6_info *rt;
3132 struct inet6_dev *idev = in6_dev_get(dev);
3133 struct net *net = dev_net(dev);
3134
3135 if (unlikely(!idev))
3136 return ERR_PTR(-ENODEV);
3137
3138 rt = ip6_dst_alloc(net, dev, 0);
3139 if (unlikely(!rt)) {
3140 in6_dev_put(idev);
3141 dst = ERR_PTR(-ENOMEM);
3142 goto out;
3143 }
3144
3145 rt->dst.flags |= DST_HOST;
3146 rt->dst.input = ip6_input;
3147 rt->dst.output = ip6_output;
3148 rt->rt6i_gateway = fl6->daddr;
3149 rt->rt6i_dst.addr = fl6->daddr;
3150 rt->rt6i_dst.plen = 128;
3151 rt->rt6i_idev = idev;
3152 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
3153
3154 /* Add this dst into uncached_list so that rt6_disable_ip() can
3155 * do proper release of the net_device
3156 */
3157 rt6_uncached_list_add(rt);
3158 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
3159
3160 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
3161
3162 out:
3163 return dst;
3164 }
3165
3166 static int ip6_dst_gc(struct dst_ops *ops)
3167 {
3168 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
3169 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
3170 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
3171 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
3172 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
3173 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
3174 int entries;
3175
3176 entries = dst_entries_get_fast(ops);
3177 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
3178 entries <= rt_max_size)
3179 goto out;
3180
3181 net->ipv6.ip6_rt_gc_expire++;
3182 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
3183 entries = dst_entries_get_slow(ops);
3184 if (entries < ops->gc_thresh)
3185 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
3186 out:
3187 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
3188 return entries > rt_max_size;
3189 }
3190
3191 static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
3192 const struct in6_addr *gw_addr, u32 tbid,
3193 int flags, struct fib6_result *res)
3194 {
3195 struct flowi6 fl6 = {
3196 .flowi6_oif = cfg->fc_ifindex,
3197 .daddr = *gw_addr,
3198 .saddr = cfg->fc_prefsrc,
3199 };
3200 struct fib6_table *table;
3201 int err;
3202
3203 table = fib6_get_table(net, tbid);
3204 if (!table)
3205 return -EINVAL;
3206
3207 if (!ipv6_addr_any(&cfg->fc_prefsrc))
3208 flags |= RT6_LOOKUP_F_HAS_SADDR;
3209
3210 flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
3211
3212 err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags);
3213 if (!err && res->f6i != net->ipv6.fib6_null_entry)
3214 fib6_select_path(net, res, &fl6, cfg->fc_ifindex,
3215 cfg->fc_ifindex != 0, NULL, flags);
3216
3217 return err;
3218 }
3219
3220 static int ip6_route_check_nh_onlink(struct net *net,
3221 struct fib6_config *cfg,
3222 const struct net_device *dev,
3223 struct netlink_ext_ack *extack)
3224 {
3225 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
3226 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3227 struct fib6_result res = {};
3228 int err;
3229
3230 err = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0, &res);
3231 if (!err && !(res.fib6_flags & RTF_REJECT) &&
3232 /* ignore match if it is the default route */
3233 !ipv6_addr_any(&res.f6i->fib6_dst.addr) &&
3234 (res.fib6_type != RTN_UNICAST || dev != res.nh->fib_nh_dev)) {
3235 NL_SET_ERR_MSG(extack,
3236 "Nexthop has invalid gateway or device mismatch");
3237 err = -EINVAL;
3238 }
3239
3240 return err;
3241 }
3242
3243 static int ip6_route_check_nh(struct net *net,
3244 struct fib6_config *cfg,
3245 struct net_device **_dev,
3246 struct inet6_dev **idev)
3247 {
3248 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3249 struct net_device *dev = _dev ? *_dev : NULL;
3250 int flags = RT6_LOOKUP_F_IFACE;
3251 struct fib6_result res = {};
3252 int err = -EHOSTUNREACH;
3253
3254 if (cfg->fc_table) {
3255 err = ip6_nh_lookup_table(net, cfg, gw_addr,
3256 cfg->fc_table, flags, &res);
3257 /* gw_addr can not require a gateway or resolve to a reject
3258 * route. If a device is given, it must match the result.
3259 */
3260 if (err || res.fib6_flags & RTF_REJECT ||
3261 res.nh->fib_nh_gw_family ||
3262 (dev && dev != res.nh->fib_nh_dev))
3263 err = -EHOSTUNREACH;
3264 }
3265
3266 if (err < 0) {
3267 struct flowi6 fl6 = {
3268 .flowi6_oif = cfg->fc_ifindex,
3269 .daddr = *gw_addr,
3270 };
3271
3272 err = fib6_lookup(net, cfg->fc_ifindex, &fl6, &res, flags);
3273 if (err || res.fib6_flags & RTF_REJECT ||
3274 res.nh->fib_nh_gw_family)
3275 err = -EHOSTUNREACH;
3276
3277 if (err)
3278 return err;
3279
3280 fib6_select_path(net, &res, &fl6, cfg->fc_ifindex,
3281 cfg->fc_ifindex != 0, NULL, flags);
3282 }
3283
3284 err = 0;
3285 if (dev) {
3286 if (dev != res.nh->fib_nh_dev)
3287 err = -EHOSTUNREACH;
3288 } else {
3289 *_dev = dev = res.nh->fib_nh_dev;
3290 dev_hold(dev);
3291 *idev = in6_dev_get(dev);
3292 }
3293
3294 return err;
3295 }
3296
3297 static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
3298 struct net_device **_dev, struct inet6_dev **idev,
3299 struct netlink_ext_ack *extack)
3300 {
3301 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3302 int gwa_type = ipv6_addr_type(gw_addr);
3303 bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
3304 const struct net_device *dev = *_dev;
3305 bool need_addr_check = !dev;
3306 int err = -EINVAL;
3307
3308 /* if gw_addr is local we will fail to detect this in case
3309 * address is still TENTATIVE (DAD in progress). rt6_lookup()
3310 * will return already-added prefix route via interface that
3311 * prefix route was assigned to, which might be non-loopback.
3312 */
3313 if (dev &&
3314 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3315 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3316 goto out;
3317 }
3318
3319 if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
3320 /* IPv6 strictly inhibits using not link-local
3321 * addresses as nexthop address.
3322 * Otherwise, router will not able to send redirects.
3323 * It is very good, but in some (rare!) circumstances
3324 * (SIT, PtP, NBMA NOARP links) it is handy to allow
3325 * some exceptions. --ANK
3326 * We allow IPv4-mapped nexthops to support RFC4798-type
3327 * addressing
3328 */
3329 if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
3330 NL_SET_ERR_MSG(extack, "Invalid gateway address");
3331 goto out;
3332 }
3333
3334 rcu_read_lock();
3335
3336 if (cfg->fc_flags & RTNH_F_ONLINK)
3337 err = ip6_route_check_nh_onlink(net, cfg, dev, extack);
3338 else
3339 err = ip6_route_check_nh(net, cfg, _dev, idev);
3340
3341 rcu_read_unlock();
3342
3343 if (err)
3344 goto out;
3345 }
3346
3347 /* reload in case device was changed */
3348 dev = *_dev;
3349
3350 err = -EINVAL;
3351 if (!dev) {
3352 NL_SET_ERR_MSG(extack, "Egress device not specified");
3353 goto out;
3354 } else if (dev->flags & IFF_LOOPBACK) {
3355 NL_SET_ERR_MSG(extack,
3356 "Egress device can not be loopback device for this route");
3357 goto out;
3358 }
3359
3360 /* if we did not check gw_addr above, do so now that the
3361 * egress device has been resolved.
3362 */
3363 if (need_addr_check &&
3364 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3365 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3366 goto out;
3367 }
3368
3369 err = 0;
3370 out:
3371 return err;
3372 }
3373
3374 static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type)
3375 {
3376 if ((flags & RTF_REJECT) ||
3377 (dev && (dev->flags & IFF_LOOPBACK) &&
3378 !(addr_type & IPV6_ADDR_LOOPBACK) &&
3379 !(flags & RTF_LOCAL)))
3380 return true;
3381
3382 return false;
3383 }
3384
3385 int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
3386 struct fib6_config *cfg, gfp_t gfp_flags,
3387 struct netlink_ext_ack *extack)
3388 {
3389 struct net_device *dev = NULL;
3390 struct inet6_dev *idev = NULL;
3391 int addr_type;
3392 int err;
3393
3394 fib6_nh->fib_nh_family = AF_INET6;
3395 #ifdef CONFIG_IPV6_ROUTER_PREF
3396 fib6_nh->last_probe = jiffies;
3397 #endif
3398
3399 err = -ENODEV;
3400 if (cfg->fc_ifindex) {
3401 dev = dev_get_by_index(net, cfg->fc_ifindex);
3402 if (!dev)
3403 goto out;
3404 idev = in6_dev_get(dev);
3405 if (!idev)
3406 goto out;
3407 }
3408
3409 if (cfg->fc_flags & RTNH_F_ONLINK) {
3410 if (!dev) {
3411 NL_SET_ERR_MSG(extack,
3412 "Nexthop device required for onlink");
3413 goto out;
3414 }
3415
3416 if (!(dev->flags & IFF_UP)) {
3417 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3418 err = -ENETDOWN;
3419 goto out;
3420 }
3421
3422 fib6_nh->fib_nh_flags |= RTNH_F_ONLINK;
3423 }
3424
3425 fib6_nh->fib_nh_weight = 1;
3426
3427 /* We cannot add true routes via loopback here,
3428 * they would result in kernel looping; promote them to reject routes
3429 */
3430 addr_type = ipv6_addr_type(&cfg->fc_dst);
3431 if (fib6_is_reject(cfg->fc_flags, dev, addr_type)) {
3432 /* hold loopback dev/idev if we haven't done so. */
3433 if (dev != net->loopback_dev) {
3434 if (dev) {
3435 dev_put(dev);
3436 in6_dev_put(idev);
3437 }
3438 dev = net->loopback_dev;
3439 dev_hold(dev);
3440 idev = in6_dev_get(dev);
3441 if (!idev) {
3442 err = -ENODEV;
3443 goto out;
3444 }
3445 }
3446 goto pcpu_alloc;
3447 }
3448
3449 if (cfg->fc_flags & RTF_GATEWAY) {
3450 err = ip6_validate_gw(net, cfg, &dev, &idev, extack);
3451 if (err)
3452 goto out;
3453
3454 fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
3455 fib6_nh->fib_nh_gw_family = AF_INET6;
3456 }
3457
3458 err = -ENODEV;
3459 if (!dev)
3460 goto out;
3461
3462 if (idev->cnf.disable_ipv6) {
3463 NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
3464 err = -EACCES;
3465 goto out;
3466 }
3467
3468 if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) {
3469 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3470 err = -ENETDOWN;
3471 goto out;
3472 }
3473
3474 if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
3475 !netif_carrier_ok(dev))
3476 fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
3477
3478 err = fib_nh_common_init(&fib6_nh->nh_common, cfg->fc_encap,
3479 cfg->fc_encap_type, cfg, gfp_flags, extack);
3480 if (err)
3481 goto out;
3482
3483 pcpu_alloc:
3484 fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags);
3485 if (!fib6_nh->rt6i_pcpu) {
3486 err = -ENOMEM;
3487 goto out;
3488 }
3489
3490 fib6_nh->fib_nh_dev = dev;
3491 fib6_nh->fib_nh_oif = dev->ifindex;
3492 err = 0;
3493 out:
3494 if (idev)
3495 in6_dev_put(idev);
3496
3497 if (err) {
3498 lwtstate_put(fib6_nh->fib_nh_lws);
3499 fib6_nh->fib_nh_lws = NULL;
3500 if (dev)
3501 dev_put(dev);
3502 }
3503
3504 return err;
3505 }
3506
3507 void fib6_nh_release(struct fib6_nh *fib6_nh)
3508 {
3509 struct rt6_exception_bucket *bucket;
3510
3511 rcu_read_lock();
3512
3513 fib6_nh_flush_exceptions(fib6_nh, NULL);
3514 bucket = fib6_nh_get_excptn_bucket(fib6_nh, NULL);
3515 if (bucket) {
3516 rcu_assign_pointer(fib6_nh->rt6i_exception_bucket, NULL);
3517 kfree(bucket);
3518 }
3519
3520 rcu_read_unlock();
3521
3522 if (fib6_nh->rt6i_pcpu) {
3523 int cpu;
3524
3525 for_each_possible_cpu(cpu) {
3526 struct rt6_info **ppcpu_rt;
3527 struct rt6_info *pcpu_rt;
3528
3529 ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu);
3530 pcpu_rt = *ppcpu_rt;
3531 if (pcpu_rt) {
3532 dst_dev_put(&pcpu_rt->dst);
3533 dst_release(&pcpu_rt->dst);
3534 *ppcpu_rt = NULL;
3535 }
3536 }
3537
3538 free_percpu(fib6_nh->rt6i_pcpu);
3539 }
3540
3541 fib_nh_common_release(&fib6_nh->nh_common);
3542 }
3543
3544 static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
3545 gfp_t gfp_flags,
3546 struct netlink_ext_ack *extack)
3547 {
3548 struct net *net = cfg->fc_nlinfo.nl_net;
3549 struct fib6_info *rt = NULL;
3550 struct nexthop *nh = NULL;
3551 struct fib6_table *table;
3552 struct fib6_nh *fib6_nh;
3553 int err = -EINVAL;
3554 int addr_type;
3555
3556 /* RTF_PCPU is an internal flag; can not be set by userspace */
3557 if (cfg->fc_flags & RTF_PCPU) {
3558 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
3559 goto out;
3560 }
3561
3562 /* RTF_CACHE is an internal flag; can not be set by userspace */
3563 if (cfg->fc_flags & RTF_CACHE) {
3564 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
3565 goto out;
3566 }
3567
3568 if (cfg->fc_type > RTN_MAX) {
3569 NL_SET_ERR_MSG(extack, "Invalid route type");
3570 goto out;
3571 }
3572
3573 if (cfg->fc_dst_len > 128) {
3574 NL_SET_ERR_MSG(extack, "Invalid prefix length");
3575 goto out;
3576 }
3577 if (cfg->fc_src_len > 128) {
3578 NL_SET_ERR_MSG(extack, "Invalid source address length");
3579 goto out;
3580 }
3581 #ifndef CONFIG_IPV6_SUBTREES
3582 if (cfg->fc_src_len) {
3583 NL_SET_ERR_MSG(extack,
3584 "Specifying source address requires IPV6_SUBTREES to be enabled");
3585 goto out;
3586 }
3587 #endif
3588 if (cfg->fc_nh_id) {
3589 nh = nexthop_find_by_id(net, cfg->fc_nh_id);
3590 if (!nh) {
3591 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
3592 goto out;
3593 }
3594 err = fib6_check_nexthop(nh, cfg, extack);
3595 if (err)
3596 goto out;
3597 }
3598
3599 err = -ENOBUFS;
3600 if (cfg->fc_nlinfo.nlh &&
3601 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
3602 table = fib6_get_table(net, cfg->fc_table);
3603 if (!table) {
3604 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
3605 table = fib6_new_table(net, cfg->fc_table);
3606 }
3607 } else {
3608 table = fib6_new_table(net, cfg->fc_table);
3609 }
3610
3611 if (!table)
3612 goto out;
3613
3614 err = -ENOMEM;
3615 rt = fib6_info_alloc(gfp_flags, !nh);
3616 if (!rt)
3617 goto out;
3618
3619 rt->fib6_metrics = ip_fib_metrics_init(net, cfg->fc_mx, cfg->fc_mx_len,
3620 extack);
3621 if (IS_ERR(rt->fib6_metrics)) {
3622 err = PTR_ERR(rt->fib6_metrics);
3623 /* Do not leave garbage there. */
3624 rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
3625 goto out;
3626 }
3627
3628 if (cfg->fc_flags & RTF_ADDRCONF)
3629 rt->dst_nocount = true;
3630
3631 if (cfg->fc_flags & RTF_EXPIRES)
3632 fib6_set_expires(rt, jiffies +
3633 clock_t_to_jiffies(cfg->fc_expires));
3634 else
3635 fib6_clean_expires(rt);
3636
3637 if (cfg->fc_protocol == RTPROT_UNSPEC)
3638 cfg->fc_protocol = RTPROT_BOOT;
3639 rt->fib6_protocol = cfg->fc_protocol;
3640
3641 rt->fib6_table = table;
3642 rt->fib6_metric = cfg->fc_metric;
3643 rt->fib6_type = cfg->fc_type ? : RTN_UNICAST;
3644 rt->fib6_flags = cfg->fc_flags & ~RTF_GATEWAY;
3645
3646 ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
3647 rt->fib6_dst.plen = cfg->fc_dst_len;
3648 if (rt->fib6_dst.plen == 128)
3649 rt->dst_host = true;
3650
3651 #ifdef CONFIG_IPV6_SUBTREES
3652 ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3653 rt->fib6_src.plen = cfg->fc_src_len;
3654 #endif
3655 if (nh) {
3656 if (!nexthop_get(nh)) {
3657 NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
3658 goto out;
3659 }
3660 if (rt->fib6_src.plen) {
3661 NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
3662 goto out;
3663 }
3664 rt->nh = nh;
3665 fib6_nh = nexthop_fib6_nh(rt->nh);
3666 } else {
3667 err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
3668 if (err)
3669 goto out;
3670
3671 fib6_nh = rt->fib6_nh;
3672
3673 /* We cannot add true routes via loopback here, they would
3674 * result in kernel looping; promote them to reject routes
3675 */
3676 addr_type = ipv6_addr_type(&cfg->fc_dst);
3677 if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev,
3678 addr_type))
3679 rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP;
3680 }
3681
3682 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
3683 struct net_device *dev = fib6_nh->fib_nh_dev;
3684
3685 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3686 NL_SET_ERR_MSG(extack, "Invalid source address");
3687 err = -EINVAL;
3688 goto out;
3689 }
3690 rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3691 rt->fib6_prefsrc.plen = 128;
3692 } else
3693 rt->fib6_prefsrc.plen = 0;
3694
3695 return rt;
3696 out:
3697 fib6_info_release(rt);
3698 return ERR_PTR(err);
3699 }
3700
3701 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
3702 struct netlink_ext_ack *extack)
3703 {
3704 struct fib6_info *rt;
3705 int err;
3706
3707 rt = ip6_route_info_create(cfg, gfp_flags, extack);
3708 if (IS_ERR(rt))
3709 return PTR_ERR(rt);
3710
3711 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3712 fib6_info_release(rt);
3713
3714 return err;
3715 }
3716
3717 static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
3718 {
3719 struct net *net = info->nl_net;
3720 struct fib6_table *table;
3721 int err;
3722
3723 if (rt == net->ipv6.fib6_null_entry) {
3724 err = -ENOENT;
3725 goto out;
3726 }
3727
3728 table = rt->fib6_table;
3729 spin_lock_bh(&table->tb6_lock);
3730 err = fib6_del(rt, info);
3731 spin_unlock_bh(&table->tb6_lock);
3732
3733 out:
3734 fib6_info_release(rt);
3735 return err;
3736 }
3737
3738 int ip6_del_rt(struct net *net, struct fib6_info *rt)
3739 {
3740 struct nl_info info = { .nl_net = net };
3741
3742 return __ip6_del_rt(rt, &info);
3743 }
3744
3745 static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
3746 {
3747 struct nl_info *info = &cfg->fc_nlinfo;
3748 struct net *net = info->nl_net;
3749 struct sk_buff *skb = NULL;
3750 struct fib6_table *table;
3751 int err = -ENOENT;
3752
3753 if (rt == net->ipv6.fib6_null_entry)
3754 goto out_put;
3755 table = rt->fib6_table;
3756 spin_lock_bh(&table->tb6_lock);
3757
3758 if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
3759 struct fib6_info *sibling, *next_sibling;
3760 struct fib6_node *fn;
3761
3762 /* prefer to send a single notification with all hops */
3763 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3764 if (skb) {
3765 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3766
3767 if (rt6_fill_node(net, skb, rt, NULL,
3768 NULL, NULL, 0, RTM_DELROUTE,
3769 info->portid, seq, 0) < 0) {
3770 kfree_skb(skb);
3771 skb = NULL;
3772 } else
3773 info->skip_notify = 1;
3774 }
3775
3776 /* 'rt' points to the first sibling route. If it is not the
3777 * leaf, then we do not need to send a notification. Otherwise,
3778 * we need to check if the last sibling has a next route or not
3779 * and emit a replace or delete notification, respectively.
3780 */
3781 info->skip_notify_kernel = 1;
3782 fn = rcu_dereference_protected(rt->fib6_node,
3783 lockdep_is_held(&table->tb6_lock));
3784 if (rcu_access_pointer(fn->leaf) == rt) {
3785 struct fib6_info *last_sibling, *replace_rt;
3786
3787 last_sibling = list_last_entry(&rt->fib6_siblings,
3788 struct fib6_info,
3789 fib6_siblings);
3790 replace_rt = rcu_dereference_protected(
3791 last_sibling->fib6_next,
3792 lockdep_is_held(&table->tb6_lock));
3793 if (replace_rt)
3794 call_fib6_entry_notifiers_replace(net,
3795 replace_rt);
3796 else
3797 call_fib6_multipath_entry_notifiers(net,
3798 FIB_EVENT_ENTRY_DEL,
3799 rt, rt->fib6_nsiblings,
3800 NULL);
3801 }
3802 list_for_each_entry_safe(sibling, next_sibling,
3803 &rt->fib6_siblings,
3804 fib6_siblings) {
3805 err = fib6_del(sibling, info);
3806 if (err)
3807 goto out_unlock;
3808 }
3809 }
3810
3811 err = fib6_del(rt, info);
3812 out_unlock:
3813 spin_unlock_bh(&table->tb6_lock);
3814 out_put:
3815 fib6_info_release(rt);
3816
3817 if (skb) {
3818 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3819 info->nlh, gfp_any());
3820 }
3821 return err;
3822 }
3823
3824 static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
3825 {
3826 int rc = -ESRCH;
3827
3828 if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
3829 goto out;
3830
3831 if (cfg->fc_flags & RTF_GATEWAY &&
3832 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
3833 goto out;
3834
3835 rc = rt6_remove_exception_rt(rt);
3836 out:
3837 return rc;
3838 }
3839
3840 static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt,
3841 struct fib6_nh *nh)
3842 {
3843 struct fib6_result res = {
3844 .f6i = rt,
3845 .nh = nh,
3846 };
3847 struct rt6_info *rt_cache;
3848
3849 rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src);
3850 if (rt_cache)
3851 return __ip6_del_cached_rt(rt_cache, cfg);
3852
3853 return 0;
3854 }
3855
3856 struct fib6_nh_del_cached_rt_arg {
3857 struct fib6_config *cfg;
3858 struct fib6_info *f6i;
3859 };
3860
3861 static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg)
3862 {
3863 struct fib6_nh_del_cached_rt_arg *arg = _arg;
3864 int rc;
3865
3866 rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh);
3867 return rc != -ESRCH ? rc : 0;
3868 }
3869
3870 static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i)
3871 {
3872 struct fib6_nh_del_cached_rt_arg arg = {
3873 .cfg = cfg,
3874 .f6i = f6i
3875 };
3876
3877 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg);
3878 }
3879
3880 static int ip6_route_del(struct fib6_config *cfg,
3881 struct netlink_ext_ack *extack)
3882 {
3883 struct fib6_table *table;
3884 struct fib6_info *rt;
3885 struct fib6_node *fn;
3886 int err = -ESRCH;
3887
3888 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
3889 if (!table) {
3890 NL_SET_ERR_MSG(extack, "FIB table does not exist");
3891 return err;
3892 }
3893
3894 rcu_read_lock();
3895
3896 fn = fib6_locate(&table->tb6_root,
3897 &cfg->fc_dst, cfg->fc_dst_len,
3898 &cfg->fc_src, cfg->fc_src_len,
3899 !(cfg->fc_flags & RTF_CACHE));
3900
3901 if (fn) {
3902 for_each_fib6_node_rt_rcu(fn) {
3903 struct fib6_nh *nh;
3904
3905 if (rt->nh && cfg->fc_nh_id &&
3906 rt->nh->id != cfg->fc_nh_id)
3907 continue;
3908
3909 if (cfg->fc_flags & RTF_CACHE) {
3910 int rc = 0;
3911
3912 if (rt->nh) {
3913 rc = ip6_del_cached_rt_nh(cfg, rt);
3914 } else if (cfg->fc_nh_id) {
3915 continue;
3916 } else {
3917 nh = rt->fib6_nh;
3918 rc = ip6_del_cached_rt(cfg, rt, nh);
3919 }
3920 if (rc != -ESRCH) {
3921 rcu_read_unlock();
3922 return rc;
3923 }
3924 continue;
3925 }
3926
3927 if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
3928 continue;
3929 if (cfg->fc_protocol &&
3930 cfg->fc_protocol != rt->fib6_protocol)
3931 continue;
3932
3933 if (rt->nh) {
3934 if (!fib6_info_hold_safe(rt))
3935 continue;
3936 rcu_read_unlock();
3937
3938 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3939 }
3940 if (cfg->fc_nh_id)
3941 continue;
3942
3943 nh = rt->fib6_nh;
3944 if (cfg->fc_ifindex &&
3945 (!nh->fib_nh_dev ||
3946 nh->fib_nh_dev->ifindex != cfg->fc_ifindex))
3947 continue;
3948 if (cfg->fc_flags & RTF_GATEWAY &&
3949 !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6))
3950 continue;
3951 if (!fib6_info_hold_safe(rt))
3952 continue;
3953 rcu_read_unlock();
3954
3955 /* if gateway was specified only delete the one hop */
3956 if (cfg->fc_flags & RTF_GATEWAY)
3957 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3958
3959 return __ip6_del_rt_siblings(rt, cfg);
3960 }
3961 }
3962 rcu_read_unlock();
3963
3964 return err;
3965 }
3966
3967 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
3968 {
3969 struct netevent_redirect netevent;
3970 struct rt6_info *rt, *nrt = NULL;
3971 struct fib6_result res = {};
3972 struct ndisc_options ndopts;
3973 struct inet6_dev *in6_dev;
3974 struct neighbour *neigh;
3975 struct rd_msg *msg;
3976 int optlen, on_link;
3977 u8 *lladdr;
3978
3979 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
3980 optlen -= sizeof(*msg);
3981
3982 if (optlen < 0) {
3983 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
3984 return;
3985 }
3986
3987 msg = (struct rd_msg *)icmp6_hdr(skb);
3988
3989 if (ipv6_addr_is_multicast(&msg->dest)) {
3990 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
3991 return;
3992 }
3993
3994 on_link = 0;
3995 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
3996 on_link = 1;
3997 } else if (ipv6_addr_type(&msg->target) !=
3998 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
3999 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
4000 return;
4001 }
4002
4003 in6_dev = __in6_dev_get(skb->dev);
4004 if (!in6_dev)
4005 return;
4006 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
4007 return;
4008
4009 /* RFC2461 8.1:
4010 * The IP source address of the Redirect MUST be the same as the current
4011 * first-hop router for the specified ICMP Destination Address.
4012 */
4013
4014 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
4015 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
4016 return;
4017 }
4018
4019 lladdr = NULL;
4020 if (ndopts.nd_opts_tgt_lladdr) {
4021 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
4022 skb->dev);
4023 if (!lladdr) {
4024 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
4025 return;
4026 }
4027 }
4028
4029 rt = (struct rt6_info *) dst;
4030 if (rt->rt6i_flags & RTF_REJECT) {
4031 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
4032 return;
4033 }
4034
4035 /* Redirect received -> path was valid.
4036 * Look, redirects are sent only in response to data packets,
4037 * so that this nexthop apparently is reachable. --ANK
4038 */
4039 dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
4040
4041 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
4042 if (!neigh)
4043 return;
4044
4045 /*
4046 * We have finally decided to accept it.
4047 */
4048
4049 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
4050 NEIGH_UPDATE_F_WEAK_OVERRIDE|
4051 NEIGH_UPDATE_F_OVERRIDE|
4052 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
4053 NEIGH_UPDATE_F_ISROUTER)),
4054 NDISC_REDIRECT, &ndopts);
4055
4056 rcu_read_lock();
4057 res.f6i = rcu_dereference(rt->from);
4058 if (!res.f6i)
4059 goto out;
4060
4061 if (res.f6i->nh) {
4062 struct fib6_nh_match_arg arg = {
4063 .dev = dst->dev,
4064 .gw = &rt->rt6i_gateway,
4065 };
4066
4067 nexthop_for_each_fib6_nh(res.f6i->nh,
4068 fib6_nh_find_match, &arg);
4069
4070 /* fib6_info uses a nexthop that does not have fib6_nh
4071 * using the dst->dev. Should be impossible
4072 */
4073 if (!arg.match)
4074 goto out;
4075 res.nh = arg.match;
4076 } else {
4077 res.nh = res.f6i->fib6_nh;
4078 }
4079
4080 res.fib6_flags = res.f6i->fib6_flags;
4081 res.fib6_type = res.f6i->fib6_type;
4082 nrt = ip6_rt_cache_alloc(&res, &msg->dest, NULL);
4083 if (!nrt)
4084 goto out;
4085
4086 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
4087 if (on_link)
4088 nrt->rt6i_flags &= ~RTF_GATEWAY;
4089
4090 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
4091
4092 /* rt6_insert_exception() will take care of duplicated exceptions */
4093 if (rt6_insert_exception(nrt, &res)) {
4094 dst_release_immediate(&nrt->dst);
4095 goto out;
4096 }
4097
4098 netevent.old = &rt->dst;
4099 netevent.new = &nrt->dst;
4100 netevent.daddr = &msg->dest;
4101 netevent.neigh = neigh;
4102 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
4103
4104 out:
4105 rcu_read_unlock();
4106 neigh_release(neigh);
4107 }
4108
4109 #ifdef CONFIG_IPV6_ROUTE_INFO
4110 static struct fib6_info *rt6_get_route_info(struct net *net,
4111 const struct in6_addr *prefix, int prefixlen,
4112 const struct in6_addr *gwaddr,
4113 struct net_device *dev)
4114 {
4115 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
4116 int ifindex = dev->ifindex;
4117 struct fib6_node *fn;
4118 struct fib6_info *rt = NULL;
4119 struct fib6_table *table;
4120
4121 table = fib6_get_table(net, tb_id);
4122 if (!table)
4123 return NULL;
4124
4125 rcu_read_lock();
4126 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
4127 if (!fn)
4128 goto out;
4129
4130 for_each_fib6_node_rt_rcu(fn) {
4131 /* these routes do not use nexthops */
4132 if (rt->nh)
4133 continue;
4134 if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex)
4135 continue;
4136 if (!(rt->fib6_flags & RTF_ROUTEINFO) ||
4137 !rt->fib6_nh->fib_nh_gw_family)
4138 continue;
4139 if (!ipv6_addr_equal(&rt->fib6_nh->fib_nh_gw6, gwaddr))
4140 continue;
4141 if (!fib6_info_hold_safe(rt))
4142 continue;
4143 break;
4144 }
4145 out:
4146 rcu_read_unlock();
4147 return rt;
4148 }
4149
4150 static struct fib6_info *rt6_add_route_info(struct net *net,
4151 const struct in6_addr *prefix, int prefixlen,
4152 const struct in6_addr *gwaddr,
4153 struct net_device *dev,
4154 unsigned int pref)
4155 {
4156 struct fib6_config cfg = {
4157 .fc_metric = IP6_RT_PRIO_USER,
4158 .fc_ifindex = dev->ifindex,
4159 .fc_dst_len = prefixlen,
4160 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
4161 RTF_UP | RTF_PREF(pref),
4162 .fc_protocol = RTPROT_RA,
4163 .fc_type = RTN_UNICAST,
4164 .fc_nlinfo.portid = 0,
4165 .fc_nlinfo.nlh = NULL,
4166 .fc_nlinfo.nl_net = net,
4167 };
4168
4169 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
4170 cfg.fc_dst = *prefix;
4171 cfg.fc_gateway = *gwaddr;
4172
4173 /* We should treat it as a default route if prefix length is 0. */
4174 if (!prefixlen)
4175 cfg.fc_flags |= RTF_DEFAULT;
4176
4177 ip6_route_add(&cfg, GFP_ATOMIC, NULL);
4178
4179 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
4180 }
4181 #endif
4182
4183 struct fib6_info *rt6_get_dflt_router(struct net *net,
4184 const struct in6_addr *addr,
4185 struct net_device *dev)
4186 {
4187 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
4188 struct fib6_info *rt;
4189 struct fib6_table *table;
4190
4191 table = fib6_get_table(net, tb_id);
4192 if (!table)
4193 return NULL;
4194
4195 rcu_read_lock();
4196 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4197 struct fib6_nh *nh;
4198
4199 /* RA routes do not use nexthops */
4200 if (rt->nh)
4201 continue;
4202
4203 nh = rt->fib6_nh;
4204 if (dev == nh->fib_nh_dev &&
4205 ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
4206 ipv6_addr_equal(&nh->fib_nh_gw6, addr))
4207 break;
4208 }
4209 if (rt && !fib6_info_hold_safe(rt))
4210 rt = NULL;
4211 rcu_read_unlock();
4212 return rt;
4213 }
4214
4215 struct fib6_info *rt6_add_dflt_router(struct net *net,
4216 const struct in6_addr *gwaddr,
4217 struct net_device *dev,
4218 unsigned int pref)
4219 {
4220 struct fib6_config cfg = {
4221 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
4222 .fc_metric = IP6_RT_PRIO_USER,
4223 .fc_ifindex = dev->ifindex,
4224 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
4225 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
4226 .fc_protocol = RTPROT_RA,
4227 .fc_type = RTN_UNICAST,
4228 .fc_nlinfo.portid = 0,
4229 .fc_nlinfo.nlh = NULL,
4230 .fc_nlinfo.nl_net = net,
4231 };
4232
4233 cfg.fc_gateway = *gwaddr;
4234
4235 if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
4236 struct fib6_table *table;
4237
4238 table = fib6_get_table(dev_net(dev), cfg.fc_table);
4239 if (table)
4240 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
4241 }
4242
4243 return rt6_get_dflt_router(net, gwaddr, dev);
4244 }
4245
4246 static void __rt6_purge_dflt_routers(struct net *net,
4247 struct fib6_table *table)
4248 {
4249 struct fib6_info *rt;
4250
4251 restart:
4252 rcu_read_lock();
4253 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4254 struct net_device *dev = fib6_info_nh_dev(rt);
4255 struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
4256
4257 if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
4258 (!idev || idev->cnf.accept_ra != 2) &&
4259 fib6_info_hold_safe(rt)) {
4260 rcu_read_unlock();
4261 ip6_del_rt(net, rt);
4262 goto restart;
4263 }
4264 }
4265 rcu_read_unlock();
4266
4267 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
4268 }
4269
4270 void rt6_purge_dflt_routers(struct net *net)
4271 {
4272 struct fib6_table *table;
4273 struct hlist_head *head;
4274 unsigned int h;
4275
4276 rcu_read_lock();
4277
4278 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
4279 head = &net->ipv6.fib_table_hash[h];
4280 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
4281 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
4282 __rt6_purge_dflt_routers(net, table);
4283 }
4284 }
4285
4286 rcu_read_unlock();
4287 }
4288
4289 static void rtmsg_to_fib6_config(struct net *net,
4290 struct in6_rtmsg *rtmsg,
4291 struct fib6_config *cfg)
4292 {
4293 *cfg = (struct fib6_config){
4294 .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
4295 : RT6_TABLE_MAIN,
4296 .fc_ifindex = rtmsg->rtmsg_ifindex,
4297 .fc_metric = rtmsg->rtmsg_metric ? : IP6_RT_PRIO_USER,
4298 .fc_expires = rtmsg->rtmsg_info,
4299 .fc_dst_len = rtmsg->rtmsg_dst_len,
4300 .fc_src_len = rtmsg->rtmsg_src_len,
4301 .fc_flags = rtmsg->rtmsg_flags,
4302 .fc_type = rtmsg->rtmsg_type,
4303
4304 .fc_nlinfo.nl_net = net,
4305
4306 .fc_dst = rtmsg->rtmsg_dst,
4307 .fc_src = rtmsg->rtmsg_src,
4308 .fc_gateway = rtmsg->rtmsg_gateway,
4309 };
4310 }
4311
4312 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
4313 {
4314 struct fib6_config cfg;
4315 struct in6_rtmsg rtmsg;
4316 int err;
4317
4318 switch (cmd) {
4319 case SIOCADDRT: /* Add a route */
4320 case SIOCDELRT: /* Delete a route */
4321 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
4322 return -EPERM;
4323 err = copy_from_user(&rtmsg, arg,
4324 sizeof(struct in6_rtmsg));
4325 if (err)
4326 return -EFAULT;
4327
4328 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
4329
4330 rtnl_lock();
4331 switch (cmd) {
4332 case SIOCADDRT:
4333 err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
4334 break;
4335 case SIOCDELRT:
4336 err = ip6_route_del(&cfg, NULL);
4337 break;
4338 default:
4339 err = -EINVAL;
4340 }
4341 rtnl_unlock();
4342
4343 return err;
4344 }
4345
4346 return -EINVAL;
4347 }
4348
4349 /*
4350 * Drop the packet on the floor
4351 */
4352
4353 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
4354 {
4355 struct dst_entry *dst = skb_dst(skb);
4356 struct net *net = dev_net(dst->dev);
4357 struct inet6_dev *idev;
4358 int type;
4359
4360 if (netif_is_l3_master(skb->dev) &&
4361 dst->dev == net->loopback_dev)
4362 idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif));
4363 else
4364 idev = ip6_dst_idev(dst);
4365
4366 switch (ipstats_mib_noroutes) {
4367 case IPSTATS_MIB_INNOROUTES:
4368 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
4369 if (type == IPV6_ADDR_ANY) {
4370 IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
4371 break;
4372 }
4373 /* FALLTHROUGH */
4374 case IPSTATS_MIB_OUTNOROUTES:
4375 IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
4376 break;
4377 }
4378
4379 /* Start over by dropping the dst for l3mdev case */
4380 if (netif_is_l3_master(skb->dev))
4381 skb_dst_drop(skb);
4382
4383 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
4384 kfree_skb(skb);
4385 return 0;
4386 }
4387
4388 static int ip6_pkt_discard(struct sk_buff *skb)
4389 {
4390 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
4391 }
4392
4393 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4394 {
4395 skb->dev = skb_dst(skb)->dev;
4396 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
4397 }
4398
4399 static int ip6_pkt_prohibit(struct sk_buff *skb)
4400 {
4401 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
4402 }
4403
4404 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4405 {
4406 skb->dev = skb_dst(skb)->dev;
4407 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
4408 }
4409
4410 /*
4411 * Allocate a dst for local (unicast / anycast) address.
4412 */
4413
4414 struct fib6_info *addrconf_f6i_alloc(struct net *net,
4415 struct inet6_dev *idev,
4416 const struct in6_addr *addr,
4417 bool anycast, gfp_t gfp_flags)
4418 {
4419 struct fib6_config cfg = {
4420 .fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL,
4421 .fc_ifindex = idev->dev->ifindex,
4422 .fc_flags = RTF_UP | RTF_NONEXTHOP,
4423 .fc_dst = *addr,
4424 .fc_dst_len = 128,
4425 .fc_protocol = RTPROT_KERNEL,
4426 .fc_nlinfo.nl_net = net,
4427 .fc_ignore_dev_down = true,
4428 };
4429 struct fib6_info *f6i;
4430
4431 if (anycast) {
4432 cfg.fc_type = RTN_ANYCAST;
4433 cfg.fc_flags |= RTF_ANYCAST;
4434 } else {
4435 cfg.fc_type = RTN_LOCAL;
4436 cfg.fc_flags |= RTF_LOCAL;
4437 }
4438
4439 f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
4440 if (!IS_ERR(f6i))
4441 f6i->dst_nocount = true;
4442 return f6i;
4443 }
4444
4445 /* remove deleted ip from prefsrc entries */
4446 struct arg_dev_net_ip {
4447 struct net_device *dev;
4448 struct net *net;
4449 struct in6_addr *addr;
4450 };
4451
4452 static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg)
4453 {
4454 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
4455 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
4456 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
4457
4458 if (!rt->nh &&
4459 ((void *)rt->fib6_nh->fib_nh_dev == dev || !dev) &&
4460 rt != net->ipv6.fib6_null_entry &&
4461 ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr)) {
4462 spin_lock_bh(&rt6_exception_lock);
4463 /* remove prefsrc entry */
4464 rt->fib6_prefsrc.plen = 0;
4465 spin_unlock_bh(&rt6_exception_lock);
4466 }
4467 return 0;
4468 }
4469
4470 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
4471 {
4472 struct net *net = dev_net(ifp->idev->dev);
4473 struct arg_dev_net_ip adni = {
4474 .dev = ifp->idev->dev,
4475 .net = net,
4476 .addr = &ifp->addr,
4477 };
4478 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
4479 }
4480
4481 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT)
4482
4483 /* Remove routers and update dst entries when gateway turn into host. */
4484 static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
4485 {
4486 struct in6_addr *gateway = (struct in6_addr *)arg;
4487 struct fib6_nh *nh;
4488
4489 /* RA routes do not use nexthops */
4490 if (rt->nh)
4491 return 0;
4492
4493 nh = rt->fib6_nh;
4494 if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
4495 nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6))
4496 return -1;
4497
4498 /* Further clean up cached routes in exception table.
4499 * This is needed because cached route may have a different
4500 * gateway than its 'parent' in the case of an ip redirect.
4501 */
4502 fib6_nh_exceptions_clean_tohost(nh, gateway);
4503
4504 return 0;
4505 }
4506
4507 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
4508 {
4509 fib6_clean_all(net, fib6_clean_tohost, gateway);
4510 }
4511
4512 struct arg_netdev_event {
4513 const struct net_device *dev;
4514 union {
4515 unsigned char nh_flags;
4516 unsigned long event;
4517 };
4518 };
4519
4520 static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
4521 {
4522 struct fib6_info *iter;
4523 struct fib6_node *fn;
4524
4525 fn = rcu_dereference_protected(rt->fib6_node,
4526 lockdep_is_held(&rt->fib6_table->tb6_lock));
4527 iter = rcu_dereference_protected(fn->leaf,
4528 lockdep_is_held(&rt->fib6_table->tb6_lock));
4529 while (iter) {
4530 if (iter->fib6_metric == rt->fib6_metric &&
4531 rt6_qualify_for_ecmp(iter))
4532 return iter;
4533 iter = rcu_dereference_protected(iter->fib6_next,
4534 lockdep_is_held(&rt->fib6_table->tb6_lock));
4535 }
4536
4537 return NULL;
4538 }
4539
4540 /* only called for fib entries with builtin fib6_nh */
4541 static bool rt6_is_dead(const struct fib6_info *rt)
4542 {
4543 if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD ||
4544 (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN &&
4545 ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev)))
4546 return true;
4547
4548 return false;
4549 }
4550
4551 static int rt6_multipath_total_weight(const struct fib6_info *rt)
4552 {
4553 struct fib6_info *iter;
4554 int total = 0;
4555
4556 if (!rt6_is_dead(rt))
4557 total += rt->fib6_nh->fib_nh_weight;
4558
4559 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
4560 if (!rt6_is_dead(iter))
4561 total += iter->fib6_nh->fib_nh_weight;
4562 }
4563
4564 return total;
4565 }
4566
4567 static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
4568 {
4569 int upper_bound = -1;
4570
4571 if (!rt6_is_dead(rt)) {
4572 *weight += rt->fib6_nh->fib_nh_weight;
4573 upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
4574 total) - 1;
4575 }
4576 atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound);
4577 }
4578
4579 static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
4580 {
4581 struct fib6_info *iter;
4582 int weight = 0;
4583
4584 rt6_upper_bound_set(rt, &weight, total);
4585
4586 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4587 rt6_upper_bound_set(iter, &weight, total);
4588 }
4589
4590 void rt6_multipath_rebalance(struct fib6_info *rt)
4591 {
4592 struct fib6_info *first;
4593 int total;
4594
4595 /* In case the entire multipath route was marked for flushing,
4596 * then there is no need to rebalance upon the removal of every
4597 * sibling route.
4598 */
4599 if (!rt->fib6_nsiblings || rt->should_flush)
4600 return;
4601
4602 /* During lookup routes are evaluated in order, so we need to
4603 * make sure upper bounds are assigned from the first sibling
4604 * onwards.
4605 */
4606 first = rt6_multipath_first_sibling(rt);
4607 if (WARN_ON_ONCE(!first))
4608 return;
4609
4610 total = rt6_multipath_total_weight(first);
4611 rt6_multipath_upper_bound_set(first, total);
4612 }
4613
4614 static int fib6_ifup(struct fib6_info *rt, void *p_arg)
4615 {
4616 const struct arg_netdev_event *arg = p_arg;
4617 struct net *net = dev_net(arg->dev);
4618
4619 if (rt != net->ipv6.fib6_null_entry && !rt->nh &&
4620 rt->fib6_nh->fib_nh_dev == arg->dev) {
4621 rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags;
4622 fib6_update_sernum_upto_root(net, rt);
4623 rt6_multipath_rebalance(rt);
4624 }
4625
4626 return 0;
4627 }
4628
4629 void rt6_sync_up(struct net_device *dev, unsigned char nh_flags)
4630 {
4631 struct arg_netdev_event arg = {
4632 .dev = dev,
4633 {
4634 .nh_flags = nh_flags,
4635 },
4636 };
4637
4638 if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev))
4639 arg.nh_flags |= RTNH_F_LINKDOWN;
4640
4641 fib6_clean_all(dev_net(dev), fib6_ifup, &arg);
4642 }
4643
4644 /* only called for fib entries with inline fib6_nh */
4645 static bool rt6_multipath_uses_dev(const struct fib6_info *rt,
4646 const struct net_device *dev)
4647 {
4648 struct fib6_info *iter;
4649
4650 if (rt->fib6_nh->fib_nh_dev == dev)
4651 return true;
4652 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4653 if (iter->fib6_nh->fib_nh_dev == dev)
4654 return true;
4655
4656 return false;
4657 }
4658
4659 static void rt6_multipath_flush(struct fib6_info *rt)
4660 {
4661 struct fib6_info *iter;
4662
4663 rt->should_flush = 1;
4664 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4665 iter->should_flush = 1;
4666 }
4667
4668 static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt,
4669 const struct net_device *down_dev)
4670 {
4671 struct fib6_info *iter;
4672 unsigned int dead = 0;
4673
4674 if (rt->fib6_nh->fib_nh_dev == down_dev ||
4675 rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4676 dead++;
4677 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4678 if (iter->fib6_nh->fib_nh_dev == down_dev ||
4679 iter->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4680 dead++;
4681
4682 return dead;
4683 }
4684
4685 static void rt6_multipath_nh_flags_set(struct fib6_info *rt,
4686 const struct net_device *dev,
4687 unsigned char nh_flags)
4688 {
4689 struct fib6_info *iter;
4690
4691 if (rt->fib6_nh->fib_nh_dev == dev)
4692 rt->fib6_nh->fib_nh_flags |= nh_flags;
4693 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4694 if (iter->fib6_nh->fib_nh_dev == dev)
4695 iter->fib6_nh->fib_nh_flags |= nh_flags;
4696 }
4697
4698 /* called with write lock held for table with rt */
4699 static int fib6_ifdown(struct fib6_info *rt, void *p_arg)
4700 {
4701 const struct arg_netdev_event *arg = p_arg;
4702 const struct net_device *dev = arg->dev;
4703 struct net *net = dev_net(dev);
4704
4705 if (rt == net->ipv6.fib6_null_entry || rt->nh)
4706 return 0;
4707
4708 switch (arg->event) {
4709 case NETDEV_UNREGISTER:
4710 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4711 case NETDEV_DOWN:
4712 if (rt->should_flush)
4713 return -1;
4714 if (!rt->fib6_nsiblings)
4715 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4716 if (rt6_multipath_uses_dev(rt, dev)) {
4717 unsigned int count;
4718
4719 count = rt6_multipath_dead_count(rt, dev);
4720 if (rt->fib6_nsiblings + 1 == count) {
4721 rt6_multipath_flush(rt);
4722 return -1;
4723 }
4724 rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
4725 RTNH_F_LINKDOWN);
4726 fib6_update_sernum(net, rt);
4727 rt6_multipath_rebalance(rt);
4728 }
4729 return -2;
4730 case NETDEV_CHANGE:
4731 if (rt->fib6_nh->fib_nh_dev != dev ||
4732 rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
4733 break;
4734 rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
4735 rt6_multipath_rebalance(rt);
4736 break;
4737 }
4738
4739 return 0;
4740 }
4741
4742 void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
4743 {
4744 struct arg_netdev_event arg = {
4745 .dev = dev,
4746 {
4747 .event = event,
4748 },
4749 };
4750 struct net *net = dev_net(dev);
4751
4752 if (net->ipv6.sysctl.skip_notify_on_dev_down)
4753 fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
4754 else
4755 fib6_clean_all(net, fib6_ifdown, &arg);
4756 }
4757
4758 void rt6_disable_ip(struct net_device *dev, unsigned long event)
4759 {
4760 rt6_sync_down_dev(dev, event);
4761 rt6_uncached_list_flush_dev(dev_net(dev), dev);
4762 neigh_ifdown(&nd_tbl, dev);
4763 }
4764
4765 struct rt6_mtu_change_arg {
4766 struct net_device *dev;
4767 unsigned int mtu;
4768 struct fib6_info *f6i;
4769 };
4770
4771 static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg)
4772 {
4773 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *)_arg;
4774 struct fib6_info *f6i = arg->f6i;
4775
4776 /* For administrative MTU increase, there is no way to discover
4777 * IPv6 PMTU increase, so PMTU increase should be updated here.
4778 * Since RFC 1981 doesn't include administrative MTU increase
4779 * update PMTU increase is a MUST. (i.e. jumbo frame)
4780 */
4781 if (nh->fib_nh_dev == arg->dev) {
4782 struct inet6_dev *idev = __in6_dev_get(arg->dev);
4783 u32 mtu = f6i->fib6_pmtu;
4784
4785 if (mtu >= arg->mtu ||
4786 (mtu < arg->mtu && mtu == idev->cnf.mtu6))
4787 fib6_metric_set(f6i, RTAX_MTU, arg->mtu);
4788
4789 spin_lock_bh(&rt6_exception_lock);
4790 rt6_exceptions_update_pmtu(idev, nh, arg->mtu);
4791 spin_unlock_bh(&rt6_exception_lock);
4792 }
4793
4794 return 0;
4795 }
4796
4797 static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
4798 {
4799 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
4800 struct inet6_dev *idev;
4801
4802 /* In IPv6 pmtu discovery is not optional,
4803 so that RTAX_MTU lock cannot disable it.
4804 We still use this lock to block changes
4805 caused by addrconf/ndisc.
4806 */
4807
4808 idev = __in6_dev_get(arg->dev);
4809 if (!idev)
4810 return 0;
4811
4812 if (fib6_metric_locked(f6i, RTAX_MTU))
4813 return 0;
4814
4815 arg->f6i = f6i;
4816 if (f6i->nh) {
4817 /* fib6_nh_mtu_change only returns 0, so this is safe */
4818 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change,
4819 arg);
4820 }
4821
4822 return fib6_nh_mtu_change(f6i->fib6_nh, arg);
4823 }
4824
4825 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
4826 {
4827 struct rt6_mtu_change_arg arg = {
4828 .dev = dev,
4829 .mtu = mtu,
4830 };
4831
4832 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
4833 }
4834
4835 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
4836 [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 },
4837 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
4838 [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
4839 [RTA_OIF] = { .type = NLA_U32 },
4840 [RTA_IIF] = { .type = NLA_U32 },
4841 [RTA_PRIORITY] = { .type = NLA_U32 },
4842 [RTA_METRICS] = { .type = NLA_NESTED },
4843 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
4844 [RTA_PREF] = { .type = NLA_U8 },
4845 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
4846 [RTA_ENCAP] = { .type = NLA_NESTED },
4847 [RTA_EXPIRES] = { .type = NLA_U32 },
4848 [RTA_UID] = { .type = NLA_U32 },
4849 [RTA_MARK] = { .type = NLA_U32 },
4850 [RTA_TABLE] = { .type = NLA_U32 },
4851 [RTA_IP_PROTO] = { .type = NLA_U8 },
4852 [RTA_SPORT] = { .type = NLA_U16 },
4853 [RTA_DPORT] = { .type = NLA_U16 },
4854 [RTA_NH_ID] = { .type = NLA_U32 },
4855 };
4856
4857 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
4858 struct fib6_config *cfg,
4859 struct netlink_ext_ack *extack)
4860 {
4861 struct rtmsg *rtm;
4862 struct nlattr *tb[RTA_MAX+1];
4863 unsigned int pref;
4864 int err;
4865
4866 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
4867 rtm_ipv6_policy, extack);
4868 if (err < 0)
4869 goto errout;
4870
4871 err = -EINVAL;
4872 rtm = nlmsg_data(nlh);
4873
4874 *cfg = (struct fib6_config){
4875 .fc_table = rtm->rtm_table,
4876 .fc_dst_len = rtm->rtm_dst_len,
4877 .fc_src_len = rtm->rtm_src_len,
4878 .fc_flags = RTF_UP,
4879 .fc_protocol = rtm->rtm_protocol,
4880 .fc_type = rtm->rtm_type,
4881
4882 .fc_nlinfo.portid = NETLINK_CB(skb).portid,
4883 .fc_nlinfo.nlh = nlh,
4884 .fc_nlinfo.nl_net = sock_net(skb->sk),
4885 };
4886
4887 if (rtm->rtm_type == RTN_UNREACHABLE ||
4888 rtm->rtm_type == RTN_BLACKHOLE ||
4889 rtm->rtm_type == RTN_PROHIBIT ||
4890 rtm->rtm_type == RTN_THROW)
4891 cfg->fc_flags |= RTF_REJECT;
4892
4893 if (rtm->rtm_type == RTN_LOCAL)
4894 cfg->fc_flags |= RTF_LOCAL;
4895
4896 if (rtm->rtm_flags & RTM_F_CLONED)
4897 cfg->fc_flags |= RTF_CACHE;
4898
4899 cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
4900
4901 if (tb[RTA_NH_ID]) {
4902 if (tb[RTA_GATEWAY] || tb[RTA_OIF] ||
4903 tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) {
4904 NL_SET_ERR_MSG(extack,
4905 "Nexthop specification and nexthop id are mutually exclusive");
4906 goto errout;
4907 }
4908 cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]);
4909 }
4910
4911 if (tb[RTA_GATEWAY]) {
4912 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
4913 cfg->fc_flags |= RTF_GATEWAY;
4914 }
4915 if (tb[RTA_VIA]) {
4916 NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute");
4917 goto errout;
4918 }
4919
4920 if (tb[RTA_DST]) {
4921 int plen = (rtm->rtm_dst_len + 7) >> 3;
4922
4923 if (nla_len(tb[RTA_DST]) < plen)
4924 goto errout;
4925
4926 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
4927 }
4928
4929 if (tb[RTA_SRC]) {
4930 int plen = (rtm->rtm_src_len + 7) >> 3;
4931
4932 if (nla_len(tb[RTA_SRC]) < plen)
4933 goto errout;
4934
4935 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
4936 }
4937
4938 if (tb[RTA_PREFSRC])
4939 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
4940
4941 if (tb[RTA_OIF])
4942 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
4943
4944 if (tb[RTA_PRIORITY])
4945 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
4946
4947 if (tb[RTA_METRICS]) {
4948 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
4949 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
4950 }
4951
4952 if (tb[RTA_TABLE])
4953 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
4954
4955 if (tb[RTA_MULTIPATH]) {
4956 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
4957 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
4958
4959 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
4960 cfg->fc_mp_len, extack);
4961 if (err < 0)
4962 goto errout;
4963 }
4964
4965 if (tb[RTA_PREF]) {
4966 pref = nla_get_u8(tb[RTA_PREF]);
4967 if (pref != ICMPV6_ROUTER_PREF_LOW &&
4968 pref != ICMPV6_ROUTER_PREF_HIGH)
4969 pref = ICMPV6_ROUTER_PREF_MEDIUM;
4970 cfg->fc_flags |= RTF_PREF(pref);
4971 }
4972
4973 if (tb[RTA_ENCAP])
4974 cfg->fc_encap = tb[RTA_ENCAP];
4975
4976 if (tb[RTA_ENCAP_TYPE]) {
4977 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
4978
4979 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
4980 if (err < 0)
4981 goto errout;
4982 }
4983
4984 if (tb[RTA_EXPIRES]) {
4985 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
4986
4987 if (addrconf_finite_timeout(timeout)) {
4988 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
4989 cfg->fc_flags |= RTF_EXPIRES;
4990 }
4991 }
4992
4993 err = 0;
4994 errout:
4995 return err;
4996 }
4997
4998 struct rt6_nh {
4999 struct fib6_info *fib6_info;
5000 struct fib6_config r_cfg;
5001 struct list_head next;
5002 };
5003
5004 static int ip6_route_info_append(struct net *net,
5005 struct list_head *rt6_nh_list,
5006 struct fib6_info *rt,
5007 struct fib6_config *r_cfg)
5008 {
5009 struct rt6_nh *nh;
5010 int err = -EEXIST;
5011
5012 list_for_each_entry(nh, rt6_nh_list, next) {
5013 /* check if fib6_info already exists */
5014 if (rt6_duplicate_nexthop(nh->fib6_info, rt))
5015 return err;
5016 }
5017
5018 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
5019 if (!nh)
5020 return -ENOMEM;
5021 nh->fib6_info = rt;
5022 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
5023 list_add_tail(&nh->next, rt6_nh_list);
5024
5025 return 0;
5026 }
5027
5028 static void ip6_route_mpath_notify(struct fib6_info *rt,
5029 struct fib6_info *rt_last,
5030 struct nl_info *info,
5031 __u16 nlflags)
5032 {
5033 /* if this is an APPEND route, then rt points to the first route
5034 * inserted and rt_last points to last route inserted. Userspace
5035 * wants a consistent dump of the route which starts at the first
5036 * nexthop. Since sibling routes are always added at the end of
5037 * the list, find the first sibling of the last route appended
5038 */
5039 if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
5040 rt = list_first_entry(&rt_last->fib6_siblings,
5041 struct fib6_info,
5042 fib6_siblings);
5043 }
5044
5045 if (rt)
5046 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
5047 }
5048
5049 static bool ip6_route_mpath_should_notify(const struct fib6_info *rt)
5050 {
5051 bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
5052 bool should_notify = false;
5053 struct fib6_info *leaf;
5054 struct fib6_node *fn;
5055
5056 rcu_read_lock();
5057 fn = rcu_dereference(rt->fib6_node);
5058 if (!fn)
5059 goto out;
5060
5061 leaf = rcu_dereference(fn->leaf);
5062 if (!leaf)
5063 goto out;
5064
5065 if (rt == leaf ||
5066 (rt_can_ecmp && rt->fib6_metric == leaf->fib6_metric &&
5067 rt6_qualify_for_ecmp(leaf)))
5068 should_notify = true;
5069 out:
5070 rcu_read_unlock();
5071
5072 return should_notify;
5073 }
5074
5075 static int ip6_route_multipath_add(struct fib6_config *cfg,
5076 struct netlink_ext_ack *extack)
5077 {
5078 struct fib6_info *rt_notif = NULL, *rt_last = NULL;
5079 struct nl_info *info = &cfg->fc_nlinfo;
5080 struct fib6_config r_cfg;
5081 struct rtnexthop *rtnh;
5082 struct fib6_info *rt;
5083 struct rt6_nh *err_nh;
5084 struct rt6_nh *nh, *nh_safe;
5085 __u16 nlflags;
5086 int remaining;
5087 int attrlen;
5088 int err = 1;
5089 int nhn = 0;
5090 int replace = (cfg->fc_nlinfo.nlh &&
5091 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
5092 LIST_HEAD(rt6_nh_list);
5093
5094 nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
5095 if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
5096 nlflags |= NLM_F_APPEND;
5097
5098 remaining = cfg->fc_mp_len;
5099 rtnh = (struct rtnexthop *)cfg->fc_mp;
5100
5101 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
5102 * fib6_info structs per nexthop
5103 */
5104 while (rtnh_ok(rtnh, remaining)) {
5105 memcpy(&r_cfg, cfg, sizeof(*cfg));
5106 if (rtnh->rtnh_ifindex)
5107 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5108
5109 attrlen = rtnh_attrlen(rtnh);
5110 if (attrlen > 0) {
5111 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5112
5113 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5114 if (nla) {
5115 r_cfg.fc_gateway = nla_get_in6_addr(nla);
5116 r_cfg.fc_flags |= RTF_GATEWAY;
5117 }
5118 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
5119 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
5120 if (nla)
5121 r_cfg.fc_encap_type = nla_get_u16(nla);
5122 }
5123
5124 r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
5125 rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
5126 if (IS_ERR(rt)) {
5127 err = PTR_ERR(rt);
5128 rt = NULL;
5129 goto cleanup;
5130 }
5131 if (!rt6_qualify_for_ecmp(rt)) {
5132 err = -EINVAL;
5133 NL_SET_ERR_MSG(extack,
5134 "Device only routes can not be added for IPv6 using the multipath API.");
5135 fib6_info_release(rt);
5136 goto cleanup;
5137 }
5138
5139 rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1;
5140
5141 err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
5142 rt, &r_cfg);
5143 if (err) {
5144 fib6_info_release(rt);
5145 goto cleanup;
5146 }
5147
5148 rtnh = rtnh_next(rtnh, &remaining);
5149 }
5150
5151 if (list_empty(&rt6_nh_list)) {
5152 NL_SET_ERR_MSG(extack,
5153 "Invalid nexthop configuration - no valid nexthops");
5154 return -EINVAL;
5155 }
5156
5157 /* for add and replace send one notification with all nexthops.
5158 * Skip the notification in fib6_add_rt2node and send one with
5159 * the full route when done
5160 */
5161 info->skip_notify = 1;
5162
5163 /* For add and replace, send one notification with all nexthops. For
5164 * append, send one notification with all appended nexthops.
5165 */
5166 info->skip_notify_kernel = 1;
5167
5168 err_nh = NULL;
5169 list_for_each_entry(nh, &rt6_nh_list, next) {
5170 err = __ip6_ins_rt(nh->fib6_info, info, extack);
5171 fib6_info_release(nh->fib6_info);
5172
5173 if (!err) {
5174 /* save reference to last route successfully inserted */
5175 rt_last = nh->fib6_info;
5176
5177 /* save reference to first route for notification */
5178 if (!rt_notif)
5179 rt_notif = nh->fib6_info;
5180 }
5181
5182 /* nh->fib6_info is used or freed at this point, reset to NULL*/
5183 nh->fib6_info = NULL;
5184 if (err) {
5185 if (replace && nhn)
5186 NL_SET_ERR_MSG_MOD(extack,
5187 "multipath route replace failed (check consistency of installed routes)");
5188 err_nh = nh;
5189 goto add_errout;
5190 }
5191
5192 /* Because each route is added like a single route we remove
5193 * these flags after the first nexthop: if there is a collision,
5194 * we have already failed to add the first nexthop:
5195 * fib6_add_rt2node() has rejected it; when replacing, old
5196 * nexthops have been replaced by first new, the rest should
5197 * be added to it.
5198 */
5199 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
5200 NLM_F_REPLACE);
5201 cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
5202 nhn++;
5203 }
5204
5205 /* An in-kernel notification should only be sent in case the new
5206 * multipath route is added as the first route in the node, or if
5207 * it was appended to it. We pass 'rt_notif' since it is the first
5208 * sibling and might allow us to skip some checks in the replace case.
5209 */
5210 if (ip6_route_mpath_should_notify(rt_notif)) {
5211 enum fib_event_type fib_event;
5212
5213 if (rt_notif->fib6_nsiblings != nhn - 1)
5214 fib_event = FIB_EVENT_ENTRY_APPEND;
5215 else
5216 fib_event = FIB_EVENT_ENTRY_REPLACE;
5217
5218 err = call_fib6_multipath_entry_notifiers(info->nl_net,
5219 fib_event, rt_notif,
5220 nhn - 1, extack);
5221 if (err) {
5222 /* Delete all the siblings that were just added */
5223 err_nh = NULL;
5224 goto add_errout;
5225 }
5226 }
5227
5228 /* success ... tell user about new route */
5229 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5230 goto cleanup;
5231
5232 add_errout:
5233 /* send notification for routes that were added so that
5234 * the delete notifications sent by ip6_route_del are
5235 * coherent
5236 */
5237 if (rt_notif)
5238 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5239
5240 /* Delete routes that were already added */
5241 list_for_each_entry(nh, &rt6_nh_list, next) {
5242 if (err_nh == nh)
5243 break;
5244 ip6_route_del(&nh->r_cfg, extack);
5245 }
5246
5247 cleanup:
5248 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
5249 if (nh->fib6_info)
5250 fib6_info_release(nh->fib6_info);
5251 list_del(&nh->next);
5252 kfree(nh);
5253 }
5254
5255 return err;
5256 }
5257
5258 static int ip6_route_multipath_del(struct fib6_config *cfg,
5259 struct netlink_ext_ack *extack)
5260 {
5261 struct fib6_config r_cfg;
5262 struct rtnexthop *rtnh;
5263 int remaining;
5264 int attrlen;
5265 int err = 1, last_err = 0;
5266
5267 remaining = cfg->fc_mp_len;
5268 rtnh = (struct rtnexthop *)cfg->fc_mp;
5269
5270 /* Parse a Multipath Entry */
5271 while (rtnh_ok(rtnh, remaining)) {
5272 memcpy(&r_cfg, cfg, sizeof(*cfg));
5273 if (rtnh->rtnh_ifindex)
5274 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5275
5276 attrlen = rtnh_attrlen(rtnh);
5277 if (attrlen > 0) {
5278 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5279
5280 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5281 if (nla) {
5282 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
5283 r_cfg.fc_flags |= RTF_GATEWAY;
5284 }
5285 }
5286 err = ip6_route_del(&r_cfg, extack);
5287 if (err)
5288 last_err = err;
5289
5290 rtnh = rtnh_next(rtnh, &remaining);
5291 }
5292
5293 return last_err;
5294 }
5295
5296 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5297 struct netlink_ext_ack *extack)
5298 {
5299 struct fib6_config cfg;
5300 int err;
5301
5302 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5303 if (err < 0)
5304 return err;
5305
5306 if (cfg.fc_nh_id &&
5307 !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id)) {
5308 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
5309 return -EINVAL;
5310 }
5311
5312 if (cfg.fc_mp)
5313 return ip6_route_multipath_del(&cfg, extack);
5314 else {
5315 cfg.fc_delete_all_nh = 1;
5316 return ip6_route_del(&cfg, extack);
5317 }
5318 }
5319
5320 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5321 struct netlink_ext_ack *extack)
5322 {
5323 struct fib6_config cfg;
5324 int err;
5325
5326 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5327 if (err < 0)
5328 return err;
5329
5330 if (cfg.fc_metric == 0)
5331 cfg.fc_metric = IP6_RT_PRIO_USER;
5332
5333 if (cfg.fc_mp)
5334 return ip6_route_multipath_add(&cfg, extack);
5335 else
5336 return ip6_route_add(&cfg, GFP_KERNEL, extack);
5337 }
5338
5339 /* add the overhead of this fib6_nh to nexthop_len */
5340 static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
5341 {
5342 int *nexthop_len = arg;
5343
5344 *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */
5345 + NLA_ALIGN(sizeof(struct rtnexthop))
5346 + nla_total_size(16); /* RTA_GATEWAY */
5347
5348 if (nh->fib_nh_lws) {
5349 /* RTA_ENCAP_TYPE */
5350 *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5351 /* RTA_ENCAP */
5352 *nexthop_len += nla_total_size(2);
5353 }
5354
5355 return 0;
5356 }
5357
5358 static size_t rt6_nlmsg_size(struct fib6_info *f6i)
5359 {
5360 int nexthop_len;
5361
5362 if (f6i->nh) {
5363 nexthop_len = nla_total_size(4); /* RTA_NH_ID */
5364 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size,
5365 &nexthop_len);
5366 } else {
5367 struct fib6_nh *nh = f6i->fib6_nh;
5368
5369 nexthop_len = 0;
5370 if (f6i->fib6_nsiblings) {
5371 nexthop_len = nla_total_size(0) /* RTA_MULTIPATH */
5372 + NLA_ALIGN(sizeof(struct rtnexthop))
5373 + nla_total_size(16) /* RTA_GATEWAY */
5374 + lwtunnel_get_encap_size(nh->fib_nh_lws);
5375
5376 nexthop_len *= f6i->fib6_nsiblings;
5377 }
5378 nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5379 }
5380
5381 return NLMSG_ALIGN(sizeof(struct rtmsg))
5382 + nla_total_size(16) /* RTA_SRC */
5383 + nla_total_size(16) /* RTA_DST */
5384 + nla_total_size(16) /* RTA_GATEWAY */
5385 + nla_total_size(16) /* RTA_PREFSRC */
5386 + nla_total_size(4) /* RTA_TABLE */
5387 + nla_total_size(4) /* RTA_IIF */
5388 + nla_total_size(4) /* RTA_OIF */
5389 + nla_total_size(4) /* RTA_PRIORITY */
5390 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
5391 + nla_total_size(sizeof(struct rta_cacheinfo))
5392 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
5393 + nla_total_size(1) /* RTA_PREF */
5394 + nexthop_len;
5395 }
5396
5397 static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh,
5398 unsigned char *flags)
5399 {
5400 if (nexthop_is_multipath(nh)) {
5401 struct nlattr *mp;
5402
5403 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5404 if (!mp)
5405 goto nla_put_failure;
5406
5407 if (nexthop_mpath_fill_node(skb, nh, AF_INET6))
5408 goto nla_put_failure;
5409
5410 nla_nest_end(skb, mp);
5411 } else {
5412 struct fib6_nh *fib6_nh;
5413
5414 fib6_nh = nexthop_fib6_nh(nh);
5415 if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6,
5416 flags, false) < 0)
5417 goto nla_put_failure;
5418 }
5419
5420 return 0;
5421
5422 nla_put_failure:
5423 return -EMSGSIZE;
5424 }
5425
5426 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
5427 struct fib6_info *rt, struct dst_entry *dst,
5428 struct in6_addr *dest, struct in6_addr *src,
5429 int iif, int type, u32 portid, u32 seq,
5430 unsigned int flags)
5431 {
5432 struct rt6_info *rt6 = (struct rt6_info *)dst;
5433 struct rt6key *rt6_dst, *rt6_src;
5434 u32 *pmetrics, table, rt6_flags;
5435 unsigned char nh_flags = 0;
5436 struct nlmsghdr *nlh;
5437 struct rtmsg *rtm;
5438 long expires = 0;
5439
5440 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
5441 if (!nlh)
5442 return -EMSGSIZE;
5443
5444 if (rt6) {
5445 rt6_dst = &rt6->rt6i_dst;
5446 rt6_src = &rt6->rt6i_src;
5447 rt6_flags = rt6->rt6i_flags;
5448 } else {
5449 rt6_dst = &rt->fib6_dst;
5450 rt6_src = &rt->fib6_src;
5451 rt6_flags = rt->fib6_flags;
5452 }
5453
5454 rtm = nlmsg_data(nlh);
5455 rtm->rtm_family = AF_INET6;
5456 rtm->rtm_dst_len = rt6_dst->plen;
5457 rtm->rtm_src_len = rt6_src->plen;
5458 rtm->rtm_tos = 0;
5459 if (rt->fib6_table)
5460 table = rt->fib6_table->tb6_id;
5461 else
5462 table = RT6_TABLE_UNSPEC;
5463 rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
5464 if (nla_put_u32(skb, RTA_TABLE, table))
5465 goto nla_put_failure;
5466
5467 rtm->rtm_type = rt->fib6_type;
5468 rtm->rtm_flags = 0;
5469 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
5470 rtm->rtm_protocol = rt->fib6_protocol;
5471
5472 if (rt6_flags & RTF_CACHE)
5473 rtm->rtm_flags |= RTM_F_CLONED;
5474
5475 if (dest) {
5476 if (nla_put_in6_addr(skb, RTA_DST, dest))
5477 goto nla_put_failure;
5478 rtm->rtm_dst_len = 128;
5479 } else if (rtm->rtm_dst_len)
5480 if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr))
5481 goto nla_put_failure;
5482 #ifdef CONFIG_IPV6_SUBTREES
5483 if (src) {
5484 if (nla_put_in6_addr(skb, RTA_SRC, src))
5485 goto nla_put_failure;
5486 rtm->rtm_src_len = 128;
5487 } else if (rtm->rtm_src_len &&
5488 nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
5489 goto nla_put_failure;
5490 #endif
5491 if (iif) {
5492 #ifdef CONFIG_IPV6_MROUTE
5493 if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
5494 int err = ip6mr_get_route(net, skb, rtm, portid);
5495
5496 if (err == 0)
5497 return 0;
5498 if (err < 0)
5499 goto nla_put_failure;
5500 } else
5501 #endif
5502 if (nla_put_u32(skb, RTA_IIF, iif))
5503 goto nla_put_failure;
5504 } else if (dest) {
5505 struct in6_addr saddr_buf;
5506 if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 &&
5507 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5508 goto nla_put_failure;
5509 }
5510
5511 if (rt->fib6_prefsrc.plen) {
5512 struct in6_addr saddr_buf;
5513 saddr_buf = rt->fib6_prefsrc.addr;
5514 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5515 goto nla_put_failure;
5516 }
5517
5518 pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics;
5519 if (rtnetlink_put_metrics(skb, pmetrics) < 0)
5520 goto nla_put_failure;
5521
5522 if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric))
5523 goto nla_put_failure;
5524
5525 /* For multipath routes, walk the siblings list and add
5526 * each as a nexthop within RTA_MULTIPATH.
5527 */
5528 if (rt6) {
5529 if (rt6_flags & RTF_GATEWAY &&
5530 nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
5531 goto nla_put_failure;
5532
5533 if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
5534 goto nla_put_failure;
5535 } else if (rt->fib6_nsiblings) {
5536 struct fib6_info *sibling, *next_sibling;
5537 struct nlattr *mp;
5538
5539 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5540 if (!mp)
5541 goto nla_put_failure;
5542
5543 if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common,
5544 rt->fib6_nh->fib_nh_weight, AF_INET6) < 0)
5545 goto nla_put_failure;
5546
5547 list_for_each_entry_safe(sibling, next_sibling,
5548 &rt->fib6_siblings, fib6_siblings) {
5549 if (fib_add_nexthop(skb, &sibling->fib6_nh->nh_common,
5550 sibling->fib6_nh->fib_nh_weight,
5551 AF_INET6) < 0)
5552 goto nla_put_failure;
5553 }
5554
5555 nla_nest_end(skb, mp);
5556 } else if (rt->nh) {
5557 if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id))
5558 goto nla_put_failure;
5559
5560 if (nexthop_is_blackhole(rt->nh))
5561 rtm->rtm_type = RTN_BLACKHOLE;
5562
5563 if (rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0)
5564 goto nla_put_failure;
5565
5566 rtm->rtm_flags |= nh_flags;
5567 } else {
5568 if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6,
5569 &nh_flags, false) < 0)
5570 goto nla_put_failure;
5571
5572 rtm->rtm_flags |= nh_flags;
5573 }
5574
5575 if (rt6_flags & RTF_EXPIRES) {
5576 expires = dst ? dst->expires : rt->expires;
5577 expires -= jiffies;
5578 }
5579
5580 if (!dst) {
5581 if (rt->offload)
5582 rtm->rtm_flags |= RTM_F_OFFLOAD;
5583 if (rt->trap)
5584 rtm->rtm_flags |= RTM_F_TRAP;
5585 }
5586
5587 if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
5588 goto nla_put_failure;
5589
5590 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
5591 goto nla_put_failure;
5592
5593
5594 nlmsg_end(skb, nlh);
5595 return 0;
5596
5597 nla_put_failure:
5598 nlmsg_cancel(skb, nlh);
5599 return -EMSGSIZE;
5600 }
5601
5602 static int fib6_info_nh_uses_dev(struct fib6_nh *nh, void *arg)
5603 {
5604 const struct net_device *dev = arg;
5605
5606 if (nh->fib_nh_dev == dev)
5607 return 1;
5608
5609 return 0;
5610 }
5611
5612 static bool fib6_info_uses_dev(const struct fib6_info *f6i,
5613 const struct net_device *dev)
5614 {
5615 if (f6i->nh) {
5616 struct net_device *_dev = (struct net_device *)dev;
5617
5618 return !!nexthop_for_each_fib6_nh(f6i->nh,
5619 fib6_info_nh_uses_dev,
5620 _dev);
5621 }
5622
5623 if (f6i->fib6_nh->fib_nh_dev == dev)
5624 return true;
5625
5626 if (f6i->fib6_nsiblings) {
5627 struct fib6_info *sibling, *next_sibling;
5628
5629 list_for_each_entry_safe(sibling, next_sibling,
5630 &f6i->fib6_siblings, fib6_siblings) {
5631 if (sibling->fib6_nh->fib_nh_dev == dev)
5632 return true;
5633 }
5634 }
5635
5636 return false;
5637 }
5638
5639 struct fib6_nh_exception_dump_walker {
5640 struct rt6_rtnl_dump_arg *dump;
5641 struct fib6_info *rt;
5642 unsigned int flags;
5643 unsigned int skip;
5644 unsigned int count;
5645 };
5646
5647 static int rt6_nh_dump_exceptions(struct fib6_nh *nh, void *arg)
5648 {
5649 struct fib6_nh_exception_dump_walker *w = arg;
5650 struct rt6_rtnl_dump_arg *dump = w->dump;
5651 struct rt6_exception_bucket *bucket;
5652 struct rt6_exception *rt6_ex;
5653 int i, err;
5654
5655 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
5656 if (!bucket)
5657 return 0;
5658
5659 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
5660 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
5661 if (w->skip) {
5662 w->skip--;
5663 continue;
5664 }
5665
5666 /* Expiration of entries doesn't bump sernum, insertion
5667 * does. Removal is triggered by insertion, so we can
5668 * rely on the fact that if entries change between two
5669 * partial dumps, this node is scanned again completely,
5670 * see rt6_insert_exception() and fib6_dump_table().
5671 *
5672 * Count expired entries we go through as handled
5673 * entries that we'll skip next time, in case of partial
5674 * node dump. Otherwise, if entries expire meanwhile,
5675 * we'll skip the wrong amount.
5676 */
5677 if (rt6_check_expired(rt6_ex->rt6i)) {
5678 w->count++;
5679 continue;
5680 }
5681
5682 err = rt6_fill_node(dump->net, dump->skb, w->rt,
5683 &rt6_ex->rt6i->dst, NULL, NULL, 0,
5684 RTM_NEWROUTE,
5685 NETLINK_CB(dump->cb->skb).portid,
5686 dump->cb->nlh->nlmsg_seq, w->flags);
5687 if (err)
5688 return err;
5689
5690 w->count++;
5691 }
5692 bucket++;
5693 }
5694
5695 return 0;
5696 }
5697
5698 /* Return -1 if done with node, number of handled routes on partial dump */
5699 int rt6_dump_route(struct fib6_info *rt, void *p_arg, unsigned int skip)
5700 {
5701 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
5702 struct fib_dump_filter *filter = &arg->filter;
5703 unsigned int flags = NLM_F_MULTI;
5704 struct net *net = arg->net;
5705 int count = 0;
5706
5707 if (rt == net->ipv6.fib6_null_entry)
5708 return -1;
5709
5710 if ((filter->flags & RTM_F_PREFIX) &&
5711 !(rt->fib6_flags & RTF_PREFIX_RT)) {
5712 /* success since this is not a prefix route */
5713 return -1;
5714 }
5715 if (filter->filter_set &&
5716 ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
5717 (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
5718 (filter->protocol && rt->fib6_protocol != filter->protocol))) {
5719 return -1;
5720 }
5721
5722 if (filter->filter_set ||
5723 !filter->dump_routes || !filter->dump_exceptions) {
5724 flags |= NLM_F_DUMP_FILTERED;
5725 }
5726
5727 if (filter->dump_routes) {
5728 if (skip) {
5729 skip--;
5730 } else {
5731 if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL,
5732 0, RTM_NEWROUTE,
5733 NETLINK_CB(arg->cb->skb).portid,
5734 arg->cb->nlh->nlmsg_seq, flags)) {
5735 return 0;
5736 }
5737 count++;
5738 }
5739 }
5740
5741 if (filter->dump_exceptions) {
5742 struct fib6_nh_exception_dump_walker w = { .dump = arg,
5743 .rt = rt,
5744 .flags = flags,
5745 .skip = skip,
5746 .count = 0 };
5747 int err;
5748
5749 rcu_read_lock();
5750 if (rt->nh) {
5751 err = nexthop_for_each_fib6_nh(rt->nh,
5752 rt6_nh_dump_exceptions,
5753 &w);
5754 } else {
5755 err = rt6_nh_dump_exceptions(rt->fib6_nh, &w);
5756 }
5757 rcu_read_unlock();
5758
5759 if (err)
5760 return count += w.count;
5761 }
5762
5763 return -1;
5764 }
5765
5766 static int inet6_rtm_valid_getroute_req(struct sk_buff *skb,
5767 const struct nlmsghdr *nlh,
5768 struct nlattr **tb,
5769 struct netlink_ext_ack *extack)
5770 {
5771 struct rtmsg *rtm;
5772 int i, err;
5773
5774 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
5775 NL_SET_ERR_MSG_MOD(extack,
5776 "Invalid header for get route request");
5777 return -EINVAL;
5778 }
5779
5780 if (!netlink_strict_get_check(skb))
5781 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
5782 rtm_ipv6_policy, extack);
5783
5784 rtm = nlmsg_data(nlh);
5785 if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
5786 (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
5787 rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope ||
5788 rtm->rtm_type) {
5789 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
5790 return -EINVAL;
5791 }
5792 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
5793 NL_SET_ERR_MSG_MOD(extack,
5794 "Invalid flags for get route request");
5795 return -EINVAL;
5796 }
5797
5798 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
5799 rtm_ipv6_policy, extack);
5800 if (err)
5801 return err;
5802
5803 if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
5804 (tb[RTA_DST] && !rtm->rtm_dst_len)) {
5805 NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6");
5806 return -EINVAL;
5807 }
5808
5809 for (i = 0; i <= RTA_MAX; i++) {
5810 if (!tb[i])
5811 continue;
5812
5813 switch (i) {
5814 case RTA_SRC:
5815 case RTA_DST:
5816 case RTA_IIF:
5817 case RTA_OIF:
5818 case RTA_MARK:
5819 case RTA_UID:
5820 case RTA_SPORT:
5821 case RTA_DPORT:
5822 case RTA_IP_PROTO:
5823 break;
5824 default:
5825 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
5826 return -EINVAL;
5827 }
5828 }
5829
5830 return 0;
5831 }
5832
5833 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5834 struct netlink_ext_ack *extack)
5835 {
5836 struct net *net = sock_net(in_skb->sk);
5837 struct nlattr *tb[RTA_MAX+1];
5838 int err, iif = 0, oif = 0;
5839 struct fib6_info *from;
5840 struct dst_entry *dst;
5841 struct rt6_info *rt;
5842 struct sk_buff *skb;
5843 struct rtmsg *rtm;
5844 struct flowi6 fl6 = {};
5845 bool fibmatch;
5846
5847 err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
5848 if (err < 0)
5849 goto errout;
5850
5851 err = -EINVAL;
5852 rtm = nlmsg_data(nlh);
5853 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
5854 fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH);
5855
5856 if (tb[RTA_SRC]) {
5857 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
5858 goto errout;
5859
5860 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
5861 }
5862
5863 if (tb[RTA_DST]) {
5864 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
5865 goto errout;
5866
5867 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
5868 }
5869
5870 if (tb[RTA_IIF])
5871 iif = nla_get_u32(tb[RTA_IIF]);
5872
5873 if (tb[RTA_OIF])
5874 oif = nla_get_u32(tb[RTA_OIF]);
5875
5876 if (tb[RTA_MARK])
5877 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
5878
5879 if (tb[RTA_UID])
5880 fl6.flowi6_uid = make_kuid(current_user_ns(),
5881 nla_get_u32(tb[RTA_UID]));
5882 else
5883 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
5884
5885 if (tb[RTA_SPORT])
5886 fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
5887
5888 if (tb[RTA_DPORT])
5889 fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
5890
5891 if (tb[RTA_IP_PROTO]) {
5892 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
5893 &fl6.flowi6_proto, AF_INET6,
5894 extack);
5895 if (err)
5896 goto errout;
5897 }
5898
5899 if (iif) {
5900 struct net_device *dev;
5901 int flags = 0;
5902
5903 rcu_read_lock();
5904
5905 dev = dev_get_by_index_rcu(net, iif);
5906 if (!dev) {
5907 rcu_read_unlock();
5908 err = -ENODEV;
5909 goto errout;
5910 }
5911
5912 fl6.flowi6_iif = iif;
5913
5914 if (!ipv6_addr_any(&fl6.saddr))
5915 flags |= RT6_LOOKUP_F_HAS_SADDR;
5916
5917 dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
5918
5919 rcu_read_unlock();
5920 } else {
5921 fl6.flowi6_oif = oif;
5922
5923 dst = ip6_route_output(net, NULL, &fl6);
5924 }
5925
5926
5927 rt = container_of(dst, struct rt6_info, dst);
5928 if (rt->dst.error) {
5929 err = rt->dst.error;
5930 ip6_rt_put(rt);
5931 goto errout;
5932 }
5933
5934 if (rt == net->ipv6.ip6_null_entry) {
5935 err = rt->dst.error;
5936 ip6_rt_put(rt);
5937 goto errout;
5938 }
5939
5940 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
5941 if (!skb) {
5942 ip6_rt_put(rt);
5943 err = -ENOBUFS;
5944 goto errout;
5945 }
5946
5947 skb_dst_set(skb, &rt->dst);
5948
5949 rcu_read_lock();
5950 from = rcu_dereference(rt->from);
5951 if (from) {
5952 if (fibmatch)
5953 err = rt6_fill_node(net, skb, from, NULL, NULL, NULL,
5954 iif, RTM_NEWROUTE,
5955 NETLINK_CB(in_skb).portid,
5956 nlh->nlmsg_seq, 0);
5957 else
5958 err = rt6_fill_node(net, skb, from, dst, &fl6.daddr,
5959 &fl6.saddr, iif, RTM_NEWROUTE,
5960 NETLINK_CB(in_skb).portid,
5961 nlh->nlmsg_seq, 0);
5962 } else {
5963 err = -ENETUNREACH;
5964 }
5965 rcu_read_unlock();
5966
5967 if (err < 0) {
5968 kfree_skb(skb);
5969 goto errout;
5970 }
5971
5972 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5973 errout:
5974 return err;
5975 }
5976
5977 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
5978 unsigned int nlm_flags)
5979 {
5980 struct sk_buff *skb;
5981 struct net *net = info->nl_net;
5982 u32 seq;
5983 int err;
5984
5985 err = -ENOBUFS;
5986 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
5987
5988 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
5989 if (!skb)
5990 goto errout;
5991
5992 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
5993 event, info->portid, seq, nlm_flags);
5994 if (err < 0) {
5995 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
5996 WARN_ON(err == -EMSGSIZE);
5997 kfree_skb(skb);
5998 goto errout;
5999 }
6000 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
6001 info->nlh, gfp_any());
6002 return;
6003 errout:
6004 if (err < 0)
6005 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6006 }
6007
6008 void fib6_rt_update(struct net *net, struct fib6_info *rt,
6009 struct nl_info *info)
6010 {
6011 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
6012 struct sk_buff *skb;
6013 int err = -ENOBUFS;
6014
6015 /* call_fib6_entry_notifiers will be removed when in-kernel notifier
6016 * is implemented and supported for nexthop objects
6017 */
6018 call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, rt, NULL);
6019
6020 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
6021 if (!skb)
6022 goto errout;
6023
6024 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
6025 RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
6026 if (err < 0) {
6027 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
6028 WARN_ON(err == -EMSGSIZE);
6029 kfree_skb(skb);
6030 goto errout;
6031 }
6032 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
6033 info->nlh, gfp_any());
6034 return;
6035 errout:
6036 if (err < 0)
6037 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6038 }
6039
6040 static int ip6_route_dev_notify(struct notifier_block *this,
6041 unsigned long event, void *ptr)
6042 {
6043 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
6044 struct net *net = dev_net(dev);
6045
6046 if (!(dev->flags & IFF_LOOPBACK))
6047 return NOTIFY_OK;
6048
6049 if (event == NETDEV_REGISTER) {
6050 net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev;
6051 net->ipv6.ip6_null_entry->dst.dev = dev;
6052 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
6053 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6054 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
6055 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
6056 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
6057 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
6058 #endif
6059 } else if (event == NETDEV_UNREGISTER &&
6060 dev->reg_state != NETREG_UNREGISTERED) {
6061 /* NETDEV_UNREGISTER could be fired for multiple times by
6062 * netdev_wait_allrefs(). Make sure we only call this once.
6063 */
6064 in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
6065 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6066 in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
6067 in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
6068 #endif
6069 }
6070
6071 return NOTIFY_OK;
6072 }
6073
6074 /*
6075 * /proc
6076 */
6077
6078 #ifdef CONFIG_PROC_FS
6079 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
6080 {
6081 struct net *net = (struct net *)seq->private;
6082 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
6083 net->ipv6.rt6_stats->fib_nodes,
6084 net->ipv6.rt6_stats->fib_route_nodes,
6085 atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
6086 net->ipv6.rt6_stats->fib_rt_entries,
6087 net->ipv6.rt6_stats->fib_rt_cache,
6088 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
6089 net->ipv6.rt6_stats->fib_discarded_routes);
6090
6091 return 0;
6092 }
6093 #endif /* CONFIG_PROC_FS */
6094
6095 #ifdef CONFIG_SYSCTL
6096
6097 static
6098 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
6099 void __user *buffer, size_t *lenp, loff_t *ppos)
6100 {
6101 struct net *net;
6102 int delay;
6103 int ret;
6104 if (!write)
6105 return -EINVAL;
6106
6107 net = (struct net *)ctl->extra1;
6108 delay = net->ipv6.sysctl.flush_delay;
6109 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6110 if (ret)
6111 return ret;
6112
6113 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
6114 return 0;
6115 }
6116
6117 static struct ctl_table ipv6_route_table_template[] = {
6118 {
6119 .procname = "flush",
6120 .data = &init_net.ipv6.sysctl.flush_delay,
6121 .maxlen = sizeof(int),
6122 .mode = 0200,
6123 .proc_handler = ipv6_sysctl_rtcache_flush
6124 },
6125 {
6126 .procname = "gc_thresh",
6127 .data = &ip6_dst_ops_template.gc_thresh,
6128 .maxlen = sizeof(int),
6129 .mode = 0644,
6130 .proc_handler = proc_dointvec,
6131 },
6132 {
6133 .procname = "max_size",
6134 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
6135 .maxlen = sizeof(int),
6136 .mode = 0644,
6137 .proc_handler = proc_dointvec,
6138 },
6139 {
6140 .procname = "gc_min_interval",
6141 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6142 .maxlen = sizeof(int),
6143 .mode = 0644,
6144 .proc_handler = proc_dointvec_jiffies,
6145 },
6146 {
6147 .procname = "gc_timeout",
6148 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
6149 .maxlen = sizeof(int),
6150 .mode = 0644,
6151 .proc_handler = proc_dointvec_jiffies,
6152 },
6153 {
6154 .procname = "gc_interval",
6155 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
6156 .maxlen = sizeof(int),
6157 .mode = 0644,
6158 .proc_handler = proc_dointvec_jiffies,
6159 },
6160 {
6161 .procname = "gc_elasticity",
6162 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
6163 .maxlen = sizeof(int),
6164 .mode = 0644,
6165 .proc_handler = proc_dointvec,
6166 },
6167 {
6168 .procname = "mtu_expires",
6169 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
6170 .maxlen = sizeof(int),
6171 .mode = 0644,
6172 .proc_handler = proc_dointvec_jiffies,
6173 },
6174 {
6175 .procname = "min_adv_mss",
6176 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
6177 .maxlen = sizeof(int),
6178 .mode = 0644,
6179 .proc_handler = proc_dointvec,
6180 },
6181 {
6182 .procname = "gc_min_interval_ms",
6183 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6184 .maxlen = sizeof(int),
6185 .mode = 0644,
6186 .proc_handler = proc_dointvec_ms_jiffies,
6187 },
6188 {
6189 .procname = "skip_notify_on_dev_down",
6190 .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down,
6191 .maxlen = sizeof(int),
6192 .mode = 0644,
6193 .proc_handler = proc_dointvec_minmax,
6194 .extra1 = SYSCTL_ZERO,
6195 .extra2 = SYSCTL_ONE,
6196 },
6197 { }
6198 };
6199
6200 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
6201 {
6202 struct ctl_table *table;
6203
6204 table = kmemdup(ipv6_route_table_template,
6205 sizeof(ipv6_route_table_template),
6206 GFP_KERNEL);
6207
6208 if (table) {
6209 table[0].data = &net->ipv6.sysctl.flush_delay;
6210 table[0].extra1 = net;
6211 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
6212 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
6213 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6214 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
6215 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
6216 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
6217 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
6218 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
6219 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6220 table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
6221
6222 /* Don't export sysctls to unprivileged users */
6223 if (net->user_ns != &init_user_ns)
6224 table[0].procname = NULL;
6225 }
6226
6227 return table;
6228 }
6229 #endif
6230
6231 static int __net_init ip6_route_net_init(struct net *net)
6232 {
6233 int ret = -ENOMEM;
6234
6235 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
6236 sizeof(net->ipv6.ip6_dst_ops));
6237
6238 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
6239 goto out_ip6_dst_ops;
6240
6241 net->ipv6.fib6_null_entry = fib6_info_alloc(GFP_KERNEL, true);
6242 if (!net->ipv6.fib6_null_entry)
6243 goto out_ip6_dst_entries;
6244 memcpy(net->ipv6.fib6_null_entry, &fib6_null_entry_template,
6245 sizeof(*net->ipv6.fib6_null_entry));
6246
6247 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
6248 sizeof(*net->ipv6.ip6_null_entry),
6249 GFP_KERNEL);
6250 if (!net->ipv6.ip6_null_entry)
6251 goto out_fib6_null_entry;
6252 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6253 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
6254 ip6_template_metrics, true);
6255 INIT_LIST_HEAD(&net->ipv6.ip6_null_entry->rt6i_uncached);
6256
6257 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6258 net->ipv6.fib6_has_custom_rules = false;
6259 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
6260 sizeof(*net->ipv6.ip6_prohibit_entry),
6261 GFP_KERNEL);
6262 if (!net->ipv6.ip6_prohibit_entry)
6263 goto out_ip6_null_entry;
6264 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6265 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
6266 ip6_template_metrics, true);
6267 INIT_LIST_HEAD(&net->ipv6.ip6_prohibit_entry->rt6i_uncached);
6268
6269 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
6270 sizeof(*net->ipv6.ip6_blk_hole_entry),
6271 GFP_KERNEL);
6272 if (!net->ipv6.ip6_blk_hole_entry)
6273 goto out_ip6_prohibit_entry;
6274 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6275 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
6276 ip6_template_metrics, true);
6277 INIT_LIST_HEAD(&net->ipv6.ip6_blk_hole_entry->rt6i_uncached);
6278 #ifdef CONFIG_IPV6_SUBTREES
6279 net->ipv6.fib6_routes_require_src = 0;
6280 #endif
6281 #endif
6282
6283 net->ipv6.sysctl.flush_delay = 0;
6284 net->ipv6.sysctl.ip6_rt_max_size = 4096;
6285 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
6286 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
6287 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
6288 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
6289 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
6290 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
6291 net->ipv6.sysctl.skip_notify_on_dev_down = 0;
6292
6293 net->ipv6.ip6_rt_gc_expire = 30*HZ;
6294
6295 ret = 0;
6296 out:
6297 return ret;
6298
6299 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6300 out_ip6_prohibit_entry:
6301 kfree(net->ipv6.ip6_prohibit_entry);
6302 out_ip6_null_entry:
6303 kfree(net->ipv6.ip6_null_entry);
6304 #endif
6305 out_fib6_null_entry:
6306 kfree(net->ipv6.fib6_null_entry);
6307 out_ip6_dst_entries:
6308 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6309 out_ip6_dst_ops:
6310 goto out;
6311 }
6312
6313 static void __net_exit ip6_route_net_exit(struct net *net)
6314 {
6315 kfree(net->ipv6.fib6_null_entry);
6316 kfree(net->ipv6.ip6_null_entry);
6317 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6318 kfree(net->ipv6.ip6_prohibit_entry);
6319 kfree(net->ipv6.ip6_blk_hole_entry);
6320 #endif
6321 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6322 }
6323
6324 static int __net_init ip6_route_net_init_late(struct net *net)
6325 {
6326 #ifdef CONFIG_PROC_FS
6327 proc_create_net("ipv6_route", 0, net->proc_net, &ipv6_route_seq_ops,
6328 sizeof(struct ipv6_route_iter));
6329 proc_create_net_single("rt6_stats", 0444, net->proc_net,
6330 rt6_stats_seq_show, NULL);
6331 #endif
6332 return 0;
6333 }
6334
6335 static void __net_exit ip6_route_net_exit_late(struct net *net)
6336 {
6337 #ifdef CONFIG_PROC_FS
6338 remove_proc_entry("ipv6_route", net->proc_net);
6339 remove_proc_entry("rt6_stats", net->proc_net);
6340 #endif
6341 }
6342
6343 static struct pernet_operations ip6_route_net_ops = {
6344 .init = ip6_route_net_init,
6345 .exit = ip6_route_net_exit,
6346 };
6347
6348 static int __net_init ipv6_inetpeer_init(struct net *net)
6349 {
6350 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
6351
6352 if (!bp)
6353 return -ENOMEM;
6354 inet_peer_base_init(bp);
6355 net->ipv6.peers = bp;
6356 return 0;
6357 }
6358
6359 static void __net_exit ipv6_inetpeer_exit(struct net *net)
6360 {
6361 struct inet_peer_base *bp = net->ipv6.peers;
6362
6363 net->ipv6.peers = NULL;
6364 inetpeer_invalidate_tree(bp);
6365 kfree(bp);
6366 }
6367
6368 static struct pernet_operations ipv6_inetpeer_ops = {
6369 .init = ipv6_inetpeer_init,
6370 .exit = ipv6_inetpeer_exit,
6371 };
6372
6373 static struct pernet_operations ip6_route_net_late_ops = {
6374 .init = ip6_route_net_init_late,
6375 .exit = ip6_route_net_exit_late,
6376 };
6377
6378 static struct notifier_block ip6_route_dev_notifier = {
6379 .notifier_call = ip6_route_dev_notify,
6380 .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
6381 };
6382
6383 void __init ip6_route_init_special_entries(void)
6384 {
6385 /* Registering of the loopback is done before this portion of code,
6386 * the loopback reference in rt6_info will not be taken, do it
6387 * manually for init_net */
6388 init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev;
6389 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
6390 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6391 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6392 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
6393 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6394 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
6395 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6396 #endif
6397 }
6398
6399 int __init ip6_route_init(void)
6400 {
6401 int ret;
6402 int cpu;
6403
6404 ret = -ENOMEM;
6405 ip6_dst_ops_template.kmem_cachep =
6406 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
6407 SLAB_HWCACHE_ALIGN, NULL);
6408 if (!ip6_dst_ops_template.kmem_cachep)
6409 goto out;
6410
6411 ret = dst_entries_init(&ip6_dst_blackhole_ops);
6412 if (ret)
6413 goto out_kmem_cache;
6414
6415 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
6416 if (ret)
6417 goto out_dst_entries;
6418
6419 ret = register_pernet_subsys(&ip6_route_net_ops);
6420 if (ret)
6421 goto out_register_inetpeer;
6422
6423 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
6424
6425 ret = fib6_init();
6426 if (ret)
6427 goto out_register_subsys;
6428
6429 ret = xfrm6_init();
6430 if (ret)
6431 goto out_fib6_init;
6432
6433 ret = fib6_rules_init();
6434 if (ret)
6435 goto xfrm6_init;
6436
6437 ret = register_pernet_subsys(&ip6_route_net_late_ops);
6438 if (ret)
6439 goto fib6_rules_init;
6440
6441 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWROUTE,
6442 inet6_rtm_newroute, NULL, 0);
6443 if (ret < 0)
6444 goto out_register_late_subsys;
6445
6446 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELROUTE,
6447 inet6_rtm_delroute, NULL, 0);
6448 if (ret < 0)
6449 goto out_register_late_subsys;
6450
6451 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE,
6452 inet6_rtm_getroute, NULL,
6453 RTNL_FLAG_DOIT_UNLOCKED);
6454 if (ret < 0)
6455 goto out_register_late_subsys;
6456
6457 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
6458 if (ret)
6459 goto out_register_late_subsys;
6460
6461 for_each_possible_cpu(cpu) {
6462 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
6463
6464 INIT_LIST_HEAD(&ul->head);
6465 spin_lock_init(&ul->lock);
6466 }
6467
6468 out:
6469 return ret;
6470
6471 out_register_late_subsys:
6472 rtnl_unregister_all(PF_INET6);
6473 unregister_pernet_subsys(&ip6_route_net_late_ops);
6474 fib6_rules_init:
6475 fib6_rules_cleanup();
6476 xfrm6_init:
6477 xfrm6_fini();
6478 out_fib6_init:
6479 fib6_gc_cleanup();
6480 out_register_subsys:
6481 unregister_pernet_subsys(&ip6_route_net_ops);
6482 out_register_inetpeer:
6483 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6484 out_dst_entries:
6485 dst_entries_destroy(&ip6_dst_blackhole_ops);
6486 out_kmem_cache:
6487 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6488 goto out;
6489 }
6490
6491 void ip6_route_cleanup(void)
6492 {
6493 unregister_netdevice_notifier(&ip6_route_dev_notifier);
6494 unregister_pernet_subsys(&ip6_route_net_late_ops);
6495 fib6_rules_cleanup();
6496 xfrm6_fini();
6497 fib6_gc_cleanup();
6498 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6499 unregister_pernet_subsys(&ip6_route_net_ops);
6500 dst_entries_destroy(&ip6_dst_blackhole_ops);
6501 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6502 }
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