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Merge branch 'nvme-5.7' of git://git.infradead.org/nvme into block-5.7
[thirdparty/linux.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
1066 return flags;
1067 }
1068
1069 static void ip6_rt_init_dst_reject(struct rt6_info *rt, u8 fib6_type)
1070 {
1071 rt->dst.error = ip6_rt_type_to_error(fib6_type);
1072
1073 switch (fib6_type) {
1074 case RTN_BLACKHOLE:
1075 rt->dst.output = dst_discard_out;
1076 rt->dst.input = dst_discard;
1077 break;
1078 case RTN_PROHIBIT:
1079 rt->dst.output = ip6_pkt_prohibit_out;
1080 rt->dst.input = ip6_pkt_prohibit;
1081 break;
1082 case RTN_THROW:
1083 case RTN_UNREACHABLE:
1084 default:
1085 rt->dst.output = ip6_pkt_discard_out;
1086 rt->dst.input = ip6_pkt_discard;
1087 break;
1088 }
1089 }
1090
1091 static void ip6_rt_init_dst(struct rt6_info *rt, const struct fib6_result *res)
1092 {
1093 struct fib6_info *f6i = res->f6i;
1094
1095 if (res->fib6_flags & RTF_REJECT) {
1096 ip6_rt_init_dst_reject(rt, res->fib6_type);
1097 return;
1098 }
1099
1100 rt->dst.error = 0;
1101 rt->dst.output = ip6_output;
1102
1103 if (res->fib6_type == RTN_LOCAL || res->fib6_type == RTN_ANYCAST) {
1104 rt->dst.input = ip6_input;
1105 } else if (ipv6_addr_type(&f6i->fib6_dst.addr) & IPV6_ADDR_MULTICAST) {
1106 rt->dst.input = ip6_mc_input;
1107 } else {
1108 rt->dst.input = ip6_forward;
1109 }
1110
1111 if (res->nh->fib_nh_lws) {
1112 rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws);
1113 lwtunnel_set_redirect(&rt->dst);
1114 }
1115
1116 rt->dst.lastuse = jiffies;
1117 }
1118
1119 /* Caller must already hold reference to @from */
1120 static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
1121 {
1122 rt->rt6i_flags &= ~RTF_EXPIRES;
1123 rcu_assign_pointer(rt->from, from);
1124 ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
1125 }
1126
1127 /* Caller must already hold reference to f6i in result */
1128 static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res)
1129 {
1130 const struct fib6_nh *nh = res->nh;
1131 const struct net_device *dev = nh->fib_nh_dev;
1132 struct fib6_info *f6i = res->f6i;
1133
1134 ip6_rt_init_dst(rt, res);
1135
1136 rt->rt6i_dst = f6i->fib6_dst;
1137 rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
1138 rt->rt6i_flags = res->fib6_flags;
1139 if (nh->fib_nh_gw_family) {
1140 rt->rt6i_gateway = nh->fib_nh_gw6;
1141 rt->rt6i_flags |= RTF_GATEWAY;
1142 }
1143 rt6_set_from(rt, f6i);
1144 #ifdef CONFIG_IPV6_SUBTREES
1145 rt->rt6i_src = f6i->fib6_src;
1146 #endif
1147 }
1148
1149 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
1150 struct in6_addr *saddr)
1151 {
1152 struct fib6_node *pn, *sn;
1153 while (1) {
1154 if (fn->fn_flags & RTN_TL_ROOT)
1155 return NULL;
1156 pn = rcu_dereference(fn->parent);
1157 sn = FIB6_SUBTREE(pn);
1158 if (sn && sn != fn)
1159 fn = fib6_node_lookup(sn, NULL, saddr);
1160 else
1161 fn = pn;
1162 if (fn->fn_flags & RTN_RTINFO)
1163 return fn;
1164 }
1165 }
1166
1167 static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
1168 {
1169 struct rt6_info *rt = *prt;
1170
1171 if (dst_hold_safe(&rt->dst))
1172 return true;
1173 if (net) {
1174 rt = net->ipv6.ip6_null_entry;
1175 dst_hold(&rt->dst);
1176 } else {
1177 rt = NULL;
1178 }
1179 *prt = rt;
1180 return false;
1181 }
1182
1183 /* called with rcu_lock held */
1184 static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res)
1185 {
1186 struct net_device *dev = res->nh->fib_nh_dev;
1187 struct fib6_info *f6i = res->f6i;
1188 unsigned short flags;
1189 struct rt6_info *nrt;
1190
1191 if (!fib6_info_hold_safe(f6i))
1192 goto fallback;
1193
1194 flags = fib6_info_dst_flags(f6i);
1195 nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
1196 if (!nrt) {
1197 fib6_info_release(f6i);
1198 goto fallback;
1199 }
1200
1201 ip6_rt_copy_init(nrt, res);
1202 return nrt;
1203
1204 fallback:
1205 nrt = dev_net(dev)->ipv6.ip6_null_entry;
1206 dst_hold(&nrt->dst);
1207 return nrt;
1208 }
1209
1210 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
1211 struct fib6_table *table,
1212 struct flowi6 *fl6,
1213 const struct sk_buff *skb,
1214 int flags)
1215 {
1216 struct fib6_result res = {};
1217 struct fib6_node *fn;
1218 struct rt6_info *rt;
1219
1220 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1221 flags &= ~RT6_LOOKUP_F_IFACE;
1222
1223 rcu_read_lock();
1224 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1225 restart:
1226 res.f6i = rcu_dereference(fn->leaf);
1227 if (!res.f6i)
1228 res.f6i = net->ipv6.fib6_null_entry;
1229 else
1230 rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif,
1231 flags);
1232
1233 if (res.f6i == net->ipv6.fib6_null_entry) {
1234 fn = fib6_backtrack(fn, &fl6->saddr);
1235 if (fn)
1236 goto restart;
1237
1238 rt = net->ipv6.ip6_null_entry;
1239 dst_hold(&rt->dst);
1240 goto out;
1241 } else if (res.fib6_flags & RTF_REJECT) {
1242 goto do_create;
1243 }
1244
1245 fib6_select_path(net, &res, fl6, fl6->flowi6_oif,
1246 fl6->flowi6_oif != 0, skb, flags);
1247
1248 /* Search through exception table */
1249 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
1250 if (rt) {
1251 if (ip6_hold_safe(net, &rt))
1252 dst_use_noref(&rt->dst, jiffies);
1253 } else {
1254 do_create:
1255 rt = ip6_create_rt_rcu(&res);
1256 }
1257
1258 out:
1259 trace_fib6_table_lookup(net, &res, table, fl6);
1260
1261 rcu_read_unlock();
1262
1263 return rt;
1264 }
1265
1266 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
1267 const struct sk_buff *skb, int flags)
1268 {
1269 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup);
1270 }
1271 EXPORT_SYMBOL_GPL(ip6_route_lookup);
1272
1273 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
1274 const struct in6_addr *saddr, int oif,
1275 const struct sk_buff *skb, int strict)
1276 {
1277 struct flowi6 fl6 = {
1278 .flowi6_oif = oif,
1279 .daddr = *daddr,
1280 };
1281 struct dst_entry *dst;
1282 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
1283
1284 if (saddr) {
1285 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
1286 flags |= RT6_LOOKUP_F_HAS_SADDR;
1287 }
1288
1289 dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
1290 if (dst->error == 0)
1291 return (struct rt6_info *) dst;
1292
1293 dst_release(dst);
1294
1295 return NULL;
1296 }
1297 EXPORT_SYMBOL(rt6_lookup);
1298
1299 /* ip6_ins_rt is called with FREE table->tb6_lock.
1300 * It takes new route entry, the addition fails by any reason the
1301 * route is released.
1302 * Caller must hold dst before calling it.
1303 */
1304
1305 static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info,
1306 struct netlink_ext_ack *extack)
1307 {
1308 int err;
1309 struct fib6_table *table;
1310
1311 table = rt->fib6_table;
1312 spin_lock_bh(&table->tb6_lock);
1313 err = fib6_add(&table->tb6_root, rt, info, extack);
1314 spin_unlock_bh(&table->tb6_lock);
1315
1316 return err;
1317 }
1318
1319 int ip6_ins_rt(struct net *net, struct fib6_info *rt)
1320 {
1321 struct nl_info info = { .nl_net = net, };
1322
1323 return __ip6_ins_rt(rt, &info, NULL);
1324 }
1325
1326 static struct rt6_info *ip6_rt_cache_alloc(const struct fib6_result *res,
1327 const struct in6_addr *daddr,
1328 const struct in6_addr *saddr)
1329 {
1330 struct fib6_info *f6i = res->f6i;
1331 struct net_device *dev;
1332 struct rt6_info *rt;
1333
1334 /*
1335 * Clone the route.
1336 */
1337
1338 if (!fib6_info_hold_safe(f6i))
1339 return NULL;
1340
1341 dev = ip6_rt_get_dev_rcu(res);
1342 rt = ip6_dst_alloc(dev_net(dev), dev, 0);
1343 if (!rt) {
1344 fib6_info_release(f6i);
1345 return NULL;
1346 }
1347
1348 ip6_rt_copy_init(rt, res);
1349 rt->rt6i_flags |= RTF_CACHE;
1350 rt->rt6i_dst.addr = *daddr;
1351 rt->rt6i_dst.plen = 128;
1352
1353 if (!rt6_is_gw_or_nonexthop(res)) {
1354 if (f6i->fib6_dst.plen != 128 &&
1355 ipv6_addr_equal(&f6i->fib6_dst.addr, daddr))
1356 rt->rt6i_flags |= RTF_ANYCAST;
1357 #ifdef CONFIG_IPV6_SUBTREES
1358 if (rt->rt6i_src.plen && saddr) {
1359 rt->rt6i_src.addr = *saddr;
1360 rt->rt6i_src.plen = 128;
1361 }
1362 #endif
1363 }
1364
1365 return rt;
1366 }
1367
1368 static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res)
1369 {
1370 struct fib6_info *f6i = res->f6i;
1371 unsigned short flags = fib6_info_dst_flags(f6i);
1372 struct net_device *dev;
1373 struct rt6_info *pcpu_rt;
1374
1375 if (!fib6_info_hold_safe(f6i))
1376 return NULL;
1377
1378 rcu_read_lock();
1379 dev = ip6_rt_get_dev_rcu(res);
1380 pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags);
1381 rcu_read_unlock();
1382 if (!pcpu_rt) {
1383 fib6_info_release(f6i);
1384 return NULL;
1385 }
1386 ip6_rt_copy_init(pcpu_rt, res);
1387 pcpu_rt->rt6i_flags |= RTF_PCPU;
1388 return pcpu_rt;
1389 }
1390
1391 /* It should be called with rcu_read_lock() acquired */
1392 static struct rt6_info *rt6_get_pcpu_route(const struct fib6_result *res)
1393 {
1394 struct rt6_info *pcpu_rt;
1395
1396 pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu);
1397
1398 return pcpu_rt;
1399 }
1400
1401 static struct rt6_info *rt6_make_pcpu_route(struct net *net,
1402 const struct fib6_result *res)
1403 {
1404 struct rt6_info *pcpu_rt, *prev, **p;
1405
1406 pcpu_rt = ip6_rt_pcpu_alloc(res);
1407 if (!pcpu_rt)
1408 return NULL;
1409
1410 p = this_cpu_ptr(res->nh->rt6i_pcpu);
1411 prev = cmpxchg(p, NULL, pcpu_rt);
1412 BUG_ON(prev);
1413
1414 if (res->f6i->fib6_destroying) {
1415 struct fib6_info *from;
1416
1417 from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
1418 fib6_info_release(from);
1419 }
1420
1421 return pcpu_rt;
1422 }
1423
1424 /* exception hash table implementation
1425 */
1426 static DEFINE_SPINLOCK(rt6_exception_lock);
1427
1428 /* Remove rt6_ex from hash table and free the memory
1429 * Caller must hold rt6_exception_lock
1430 */
1431 static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
1432 struct rt6_exception *rt6_ex)
1433 {
1434 struct fib6_info *from;
1435 struct net *net;
1436
1437 if (!bucket || !rt6_ex)
1438 return;
1439
1440 net = dev_net(rt6_ex->rt6i->dst.dev);
1441 net->ipv6.rt6_stats->fib_rt_cache--;
1442
1443 /* purge completely the exception to allow releasing the held resources:
1444 * some [sk] cache may keep the dst around for unlimited time
1445 */
1446 from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL);
1447 fib6_info_release(from);
1448 dst_dev_put(&rt6_ex->rt6i->dst);
1449
1450 hlist_del_rcu(&rt6_ex->hlist);
1451 dst_release(&rt6_ex->rt6i->dst);
1452 kfree_rcu(rt6_ex, rcu);
1453 WARN_ON_ONCE(!bucket->depth);
1454 bucket->depth--;
1455 }
1456
1457 /* Remove oldest rt6_ex in bucket and free the memory
1458 * Caller must hold rt6_exception_lock
1459 */
1460 static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
1461 {
1462 struct rt6_exception *rt6_ex, *oldest = NULL;
1463
1464 if (!bucket)
1465 return;
1466
1467 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1468 if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
1469 oldest = rt6_ex;
1470 }
1471 rt6_remove_exception(bucket, oldest);
1472 }
1473
1474 static u32 rt6_exception_hash(const struct in6_addr *dst,
1475 const struct in6_addr *src)
1476 {
1477 static u32 seed __read_mostly;
1478 u32 val;
1479
1480 net_get_random_once(&seed, sizeof(seed));
1481 val = jhash2((const u32 *)dst, sizeof(*dst)/sizeof(u32), seed);
1482
1483 #ifdef CONFIG_IPV6_SUBTREES
1484 if (src)
1485 val = jhash2((const u32 *)src, sizeof(*src)/sizeof(u32), val);
1486 #endif
1487 return hash_32(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
1488 }
1489
1490 /* Helper function to find the cached rt in the hash table
1491 * and update bucket pointer to point to the bucket for this
1492 * (daddr, saddr) pair
1493 * Caller must hold rt6_exception_lock
1494 */
1495 static struct rt6_exception *
1496 __rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
1497 const struct in6_addr *daddr,
1498 const struct in6_addr *saddr)
1499 {
1500 struct rt6_exception *rt6_ex;
1501 u32 hval;
1502
1503 if (!(*bucket) || !daddr)
1504 return NULL;
1505
1506 hval = rt6_exception_hash(daddr, saddr);
1507 *bucket += hval;
1508
1509 hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
1510 struct rt6_info *rt6 = rt6_ex->rt6i;
1511 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1512
1513 #ifdef CONFIG_IPV6_SUBTREES
1514 if (matched && saddr)
1515 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1516 #endif
1517 if (matched)
1518 return rt6_ex;
1519 }
1520 return NULL;
1521 }
1522
1523 /* Helper function to find the cached rt in the hash table
1524 * and update bucket pointer to point to the bucket for this
1525 * (daddr, saddr) pair
1526 * Caller must hold rcu_read_lock()
1527 */
1528 static struct rt6_exception *
1529 __rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
1530 const struct in6_addr *daddr,
1531 const struct in6_addr *saddr)
1532 {
1533 struct rt6_exception *rt6_ex;
1534 u32 hval;
1535
1536 WARN_ON_ONCE(!rcu_read_lock_held());
1537
1538 if (!(*bucket) || !daddr)
1539 return NULL;
1540
1541 hval = rt6_exception_hash(daddr, saddr);
1542 *bucket += hval;
1543
1544 hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
1545 struct rt6_info *rt6 = rt6_ex->rt6i;
1546 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1547
1548 #ifdef CONFIG_IPV6_SUBTREES
1549 if (matched && saddr)
1550 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1551 #endif
1552 if (matched)
1553 return rt6_ex;
1554 }
1555 return NULL;
1556 }
1557
1558 static unsigned int fib6_mtu(const struct fib6_result *res)
1559 {
1560 const struct fib6_nh *nh = res->nh;
1561 unsigned int mtu;
1562
1563 if (res->f6i->fib6_pmtu) {
1564 mtu = res->f6i->fib6_pmtu;
1565 } else {
1566 struct net_device *dev = nh->fib_nh_dev;
1567 struct inet6_dev *idev;
1568
1569 rcu_read_lock();
1570 idev = __in6_dev_get(dev);
1571 mtu = idev->cnf.mtu6;
1572 rcu_read_unlock();
1573 }
1574
1575 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1576
1577 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
1578 }
1579
1580 #define FIB6_EXCEPTION_BUCKET_FLUSHED 0x1UL
1581
1582 /* used when the flushed bit is not relevant, only access to the bucket
1583 * (ie., all bucket users except rt6_insert_exception);
1584 *
1585 * called under rcu lock; sometimes called with rt6_exception_lock held
1586 */
1587 static
1588 struct rt6_exception_bucket *fib6_nh_get_excptn_bucket(const struct fib6_nh *nh,
1589 spinlock_t *lock)
1590 {
1591 struct rt6_exception_bucket *bucket;
1592
1593 if (lock)
1594 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1595 lockdep_is_held(lock));
1596 else
1597 bucket = rcu_dereference(nh->rt6i_exception_bucket);
1598
1599 /* remove bucket flushed bit if set */
1600 if (bucket) {
1601 unsigned long p = (unsigned long)bucket;
1602
1603 p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED;
1604 bucket = (struct rt6_exception_bucket *)p;
1605 }
1606
1607 return bucket;
1608 }
1609
1610 static bool fib6_nh_excptn_bucket_flushed(struct rt6_exception_bucket *bucket)
1611 {
1612 unsigned long p = (unsigned long)bucket;
1613
1614 return !!(p & FIB6_EXCEPTION_BUCKET_FLUSHED);
1615 }
1616
1617 /* called with rt6_exception_lock held */
1618 static void fib6_nh_excptn_bucket_set_flushed(struct fib6_nh *nh,
1619 spinlock_t *lock)
1620 {
1621 struct rt6_exception_bucket *bucket;
1622 unsigned long p;
1623
1624 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1625 lockdep_is_held(lock));
1626
1627 p = (unsigned long)bucket;
1628 p |= FIB6_EXCEPTION_BUCKET_FLUSHED;
1629 bucket = (struct rt6_exception_bucket *)p;
1630 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1631 }
1632
1633 static int rt6_insert_exception(struct rt6_info *nrt,
1634 const struct fib6_result *res)
1635 {
1636 struct net *net = dev_net(nrt->dst.dev);
1637 struct rt6_exception_bucket *bucket;
1638 struct fib6_info *f6i = res->f6i;
1639 struct in6_addr *src_key = NULL;
1640 struct rt6_exception *rt6_ex;
1641 struct fib6_nh *nh = res->nh;
1642 int err = 0;
1643
1644 spin_lock_bh(&rt6_exception_lock);
1645
1646 bucket = rcu_dereference_protected(nh->rt6i_exception_bucket,
1647 lockdep_is_held(&rt6_exception_lock));
1648 if (!bucket) {
1649 bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
1650 GFP_ATOMIC);
1651 if (!bucket) {
1652 err = -ENOMEM;
1653 goto out;
1654 }
1655 rcu_assign_pointer(nh->rt6i_exception_bucket, bucket);
1656 } else if (fib6_nh_excptn_bucket_flushed(bucket)) {
1657 err = -EINVAL;
1658 goto out;
1659 }
1660
1661 #ifdef CONFIG_IPV6_SUBTREES
1662 /* fib6_src.plen != 0 indicates f6i is in subtree
1663 * and exception table is indexed by a hash of
1664 * both fib6_dst and fib6_src.
1665 * Otherwise, the exception table is indexed by
1666 * a hash of only fib6_dst.
1667 */
1668 if (f6i->fib6_src.plen)
1669 src_key = &nrt->rt6i_src.addr;
1670 #endif
1671 /* rt6_mtu_change() might lower mtu on f6i.
1672 * Only insert this exception route if its mtu
1673 * is less than f6i's mtu value.
1674 */
1675 if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(res)) {
1676 err = -EINVAL;
1677 goto out;
1678 }
1679
1680 rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
1681 src_key);
1682 if (rt6_ex)
1683 rt6_remove_exception(bucket, rt6_ex);
1684
1685 rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
1686 if (!rt6_ex) {
1687 err = -ENOMEM;
1688 goto out;
1689 }
1690 rt6_ex->rt6i = nrt;
1691 rt6_ex->stamp = jiffies;
1692 hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
1693 bucket->depth++;
1694 net->ipv6.rt6_stats->fib_rt_cache++;
1695
1696 if (bucket->depth > FIB6_MAX_DEPTH)
1697 rt6_exception_remove_oldest(bucket);
1698
1699 out:
1700 spin_unlock_bh(&rt6_exception_lock);
1701
1702 /* Update fn->fn_sernum to invalidate all cached dst */
1703 if (!err) {
1704 spin_lock_bh(&f6i->fib6_table->tb6_lock);
1705 fib6_update_sernum(net, f6i);
1706 spin_unlock_bh(&f6i->fib6_table->tb6_lock);
1707 fib6_force_start_gc(net);
1708 }
1709
1710 return err;
1711 }
1712
1713 static void fib6_nh_flush_exceptions(struct fib6_nh *nh, struct fib6_info *from)
1714 {
1715 struct rt6_exception_bucket *bucket;
1716 struct rt6_exception *rt6_ex;
1717 struct hlist_node *tmp;
1718 int i;
1719
1720 spin_lock_bh(&rt6_exception_lock);
1721
1722 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1723 if (!bucket)
1724 goto out;
1725
1726 /* Prevent rt6_insert_exception() to recreate the bucket list */
1727 if (!from)
1728 fib6_nh_excptn_bucket_set_flushed(nh, &rt6_exception_lock);
1729
1730 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1731 hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist) {
1732 if (!from ||
1733 rcu_access_pointer(rt6_ex->rt6i->from) == from)
1734 rt6_remove_exception(bucket, rt6_ex);
1735 }
1736 WARN_ON_ONCE(!from && bucket->depth);
1737 bucket++;
1738 }
1739 out:
1740 spin_unlock_bh(&rt6_exception_lock);
1741 }
1742
1743 static int rt6_nh_flush_exceptions(struct fib6_nh *nh, void *arg)
1744 {
1745 struct fib6_info *f6i = arg;
1746
1747 fib6_nh_flush_exceptions(nh, f6i);
1748
1749 return 0;
1750 }
1751
1752 void rt6_flush_exceptions(struct fib6_info *f6i)
1753 {
1754 if (f6i->nh)
1755 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions,
1756 f6i);
1757 else
1758 fib6_nh_flush_exceptions(f6i->fib6_nh, f6i);
1759 }
1760
1761 /* Find cached rt in the hash table inside passed in rt
1762 * Caller has to hold rcu_read_lock()
1763 */
1764 static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
1765 const struct in6_addr *daddr,
1766 const struct in6_addr *saddr)
1767 {
1768 const struct in6_addr *src_key = NULL;
1769 struct rt6_exception_bucket *bucket;
1770 struct rt6_exception *rt6_ex;
1771 struct rt6_info *ret = NULL;
1772
1773 #ifdef CONFIG_IPV6_SUBTREES
1774 /* fib6i_src.plen != 0 indicates f6i is in subtree
1775 * and exception table is indexed by a hash of
1776 * both fib6_dst and fib6_src.
1777 * However, the src addr used to create the hash
1778 * might not be exactly the passed in saddr which
1779 * is a /128 addr from the flow.
1780 * So we need to use f6i->fib6_src to redo lookup
1781 * if the passed in saddr does not find anything.
1782 * (See the logic in ip6_rt_cache_alloc() on how
1783 * rt->rt6i_src is updated.)
1784 */
1785 if (res->f6i->fib6_src.plen)
1786 src_key = saddr;
1787 find_ex:
1788 #endif
1789 bucket = fib6_nh_get_excptn_bucket(res->nh, NULL);
1790 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
1791
1792 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
1793 ret = rt6_ex->rt6i;
1794
1795 #ifdef CONFIG_IPV6_SUBTREES
1796 /* Use fib6_src as src_key and redo lookup */
1797 if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) {
1798 src_key = &res->f6i->fib6_src.addr;
1799 goto find_ex;
1800 }
1801 #endif
1802
1803 return ret;
1804 }
1805
1806 /* Remove the passed in cached rt from the hash table that contains it */
1807 static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen,
1808 const struct rt6_info *rt)
1809 {
1810 const struct in6_addr *src_key = NULL;
1811 struct rt6_exception_bucket *bucket;
1812 struct rt6_exception *rt6_ex;
1813 int err;
1814
1815 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
1816 return -ENOENT;
1817
1818 spin_lock_bh(&rt6_exception_lock);
1819 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1820
1821 #ifdef CONFIG_IPV6_SUBTREES
1822 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1823 * and exception table is indexed by a hash of
1824 * both rt6i_dst and rt6i_src.
1825 * Otherwise, the exception table is indexed by
1826 * a hash of only rt6i_dst.
1827 */
1828 if (plen)
1829 src_key = &rt->rt6i_src.addr;
1830 #endif
1831 rt6_ex = __rt6_find_exception_spinlock(&bucket,
1832 &rt->rt6i_dst.addr,
1833 src_key);
1834 if (rt6_ex) {
1835 rt6_remove_exception(bucket, rt6_ex);
1836 err = 0;
1837 } else {
1838 err = -ENOENT;
1839 }
1840
1841 spin_unlock_bh(&rt6_exception_lock);
1842 return err;
1843 }
1844
1845 struct fib6_nh_excptn_arg {
1846 struct rt6_info *rt;
1847 int plen;
1848 };
1849
1850 static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg)
1851 {
1852 struct fib6_nh_excptn_arg *arg = _arg;
1853 int err;
1854
1855 err = fib6_nh_remove_exception(nh, arg->plen, arg->rt);
1856 if (err == 0)
1857 return 1;
1858
1859 return 0;
1860 }
1861
1862 static int rt6_remove_exception_rt(struct rt6_info *rt)
1863 {
1864 struct fib6_info *from;
1865
1866 from = rcu_dereference(rt->from);
1867 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1868 return -EINVAL;
1869
1870 if (from->nh) {
1871 struct fib6_nh_excptn_arg arg = {
1872 .rt = rt,
1873 .plen = from->fib6_src.plen
1874 };
1875 int rc;
1876
1877 /* rc = 1 means an entry was found */
1878 rc = nexthop_for_each_fib6_nh(from->nh,
1879 rt6_nh_remove_exception_rt,
1880 &arg);
1881 return rc ? 0 : -ENOENT;
1882 }
1883
1884 return fib6_nh_remove_exception(from->fib6_nh,
1885 from->fib6_src.plen, rt);
1886 }
1887
1888 /* Find rt6_ex which contains the passed in rt cache and
1889 * refresh its stamp
1890 */
1891 static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen,
1892 const struct rt6_info *rt)
1893 {
1894 const struct in6_addr *src_key = NULL;
1895 struct rt6_exception_bucket *bucket;
1896 struct rt6_exception *rt6_ex;
1897
1898 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
1899 #ifdef CONFIG_IPV6_SUBTREES
1900 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1901 * and exception table is indexed by a hash of
1902 * both rt6i_dst and rt6i_src.
1903 * Otherwise, the exception table is indexed by
1904 * a hash of only rt6i_dst.
1905 */
1906 if (plen)
1907 src_key = &rt->rt6i_src.addr;
1908 #endif
1909 rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key);
1910 if (rt6_ex)
1911 rt6_ex->stamp = jiffies;
1912 }
1913
1914 struct fib6_nh_match_arg {
1915 const struct net_device *dev;
1916 const struct in6_addr *gw;
1917 struct fib6_nh *match;
1918 };
1919
1920 /* determine if fib6_nh has given device and gateway */
1921 static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg)
1922 {
1923 struct fib6_nh_match_arg *arg = _arg;
1924
1925 if (arg->dev != nh->fib_nh_dev ||
1926 (arg->gw && !nh->fib_nh_gw_family) ||
1927 (!arg->gw && nh->fib_nh_gw_family) ||
1928 (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6)))
1929 return 0;
1930
1931 arg->match = nh;
1932
1933 /* found a match, break the loop */
1934 return 1;
1935 }
1936
1937 static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
1938 {
1939 struct fib6_info *from;
1940 struct fib6_nh *fib6_nh;
1941
1942 rcu_read_lock();
1943
1944 from = rcu_dereference(rt->from);
1945 if (!from || !(rt->rt6i_flags & RTF_CACHE))
1946 goto unlock;
1947
1948 if (from->nh) {
1949 struct fib6_nh_match_arg arg = {
1950 .dev = rt->dst.dev,
1951 .gw = &rt->rt6i_gateway,
1952 };
1953
1954 nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg);
1955
1956 if (!arg.match)
1957 goto unlock;
1958 fib6_nh = arg.match;
1959 } else {
1960 fib6_nh = from->fib6_nh;
1961 }
1962 fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt);
1963 unlock:
1964 rcu_read_unlock();
1965 }
1966
1967 static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
1968 struct rt6_info *rt, int mtu)
1969 {
1970 /* If the new MTU is lower than the route PMTU, this new MTU will be the
1971 * lowest MTU in the path: always allow updating the route PMTU to
1972 * reflect PMTU decreases.
1973 *
1974 * If the new MTU is higher, and the route PMTU is equal to the local
1975 * MTU, this means the old MTU is the lowest in the path, so allow
1976 * updating it: if other nodes now have lower MTUs, PMTU discovery will
1977 * handle this.
1978 */
1979
1980 if (dst_mtu(&rt->dst) >= mtu)
1981 return true;
1982
1983 if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
1984 return true;
1985
1986 return false;
1987 }
1988
1989 static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
1990 const struct fib6_nh *nh, int mtu)
1991 {
1992 struct rt6_exception_bucket *bucket;
1993 struct rt6_exception *rt6_ex;
1994 int i;
1995
1996 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
1997 if (!bucket)
1998 return;
1999
2000 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2001 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
2002 struct rt6_info *entry = rt6_ex->rt6i;
2003
2004 /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
2005 * route), the metrics of its rt->from have already
2006 * been updated.
2007 */
2008 if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
2009 rt6_mtu_change_route_allowed(idev, entry, mtu))
2010 dst_metric_set(&entry->dst, RTAX_MTU, mtu);
2011 }
2012 bucket++;
2013 }
2014 }
2015
2016 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2017
2018 static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh,
2019 const struct in6_addr *gateway)
2020 {
2021 struct rt6_exception_bucket *bucket;
2022 struct rt6_exception *rt6_ex;
2023 struct hlist_node *tmp;
2024 int i;
2025
2026 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2027 return;
2028
2029 spin_lock_bh(&rt6_exception_lock);
2030 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2031 if (bucket) {
2032 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2033 hlist_for_each_entry_safe(rt6_ex, tmp,
2034 &bucket->chain, hlist) {
2035 struct rt6_info *entry = rt6_ex->rt6i;
2036
2037 if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
2038 RTF_CACHE_GATEWAY &&
2039 ipv6_addr_equal(gateway,
2040 &entry->rt6i_gateway)) {
2041 rt6_remove_exception(bucket, rt6_ex);
2042 }
2043 }
2044 bucket++;
2045 }
2046 }
2047
2048 spin_unlock_bh(&rt6_exception_lock);
2049 }
2050
2051 static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
2052 struct rt6_exception *rt6_ex,
2053 struct fib6_gc_args *gc_args,
2054 unsigned long now)
2055 {
2056 struct rt6_info *rt = rt6_ex->rt6i;
2057
2058 /* we are pruning and obsoleting aged-out and non gateway exceptions
2059 * even if others have still references to them, so that on next
2060 * dst_check() such references can be dropped.
2061 * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
2062 * expired, independently from their aging, as per RFC 8201 section 4
2063 */
2064 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
2065 if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
2066 RT6_TRACE("aging clone %p\n", rt);
2067 rt6_remove_exception(bucket, rt6_ex);
2068 return;
2069 }
2070 } else if (time_after(jiffies, rt->dst.expires)) {
2071 RT6_TRACE("purging expired route %p\n", rt);
2072 rt6_remove_exception(bucket, rt6_ex);
2073 return;
2074 }
2075
2076 if (rt->rt6i_flags & RTF_GATEWAY) {
2077 struct neighbour *neigh;
2078 __u8 neigh_flags = 0;
2079
2080 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
2081 if (neigh)
2082 neigh_flags = neigh->flags;
2083
2084 if (!(neigh_flags & NTF_ROUTER)) {
2085 RT6_TRACE("purging route %p via non-router but gateway\n",
2086 rt);
2087 rt6_remove_exception(bucket, rt6_ex);
2088 return;
2089 }
2090 }
2091
2092 gc_args->more++;
2093 }
2094
2095 static void fib6_nh_age_exceptions(const struct fib6_nh *nh,
2096 struct fib6_gc_args *gc_args,
2097 unsigned long now)
2098 {
2099 struct rt6_exception_bucket *bucket;
2100 struct rt6_exception *rt6_ex;
2101 struct hlist_node *tmp;
2102 int i;
2103
2104 if (!rcu_access_pointer(nh->rt6i_exception_bucket))
2105 return;
2106
2107 rcu_read_lock_bh();
2108 spin_lock(&rt6_exception_lock);
2109 bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
2110 if (bucket) {
2111 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
2112 hlist_for_each_entry_safe(rt6_ex, tmp,
2113 &bucket->chain, hlist) {
2114 rt6_age_examine_exception(bucket, rt6_ex,
2115 gc_args, now);
2116 }
2117 bucket++;
2118 }
2119 }
2120 spin_unlock(&rt6_exception_lock);
2121 rcu_read_unlock_bh();
2122 }
2123
2124 struct fib6_nh_age_excptn_arg {
2125 struct fib6_gc_args *gc_args;
2126 unsigned long now;
2127 };
2128
2129 static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg)
2130 {
2131 struct fib6_nh_age_excptn_arg *arg = _arg;
2132
2133 fib6_nh_age_exceptions(nh, arg->gc_args, arg->now);
2134 return 0;
2135 }
2136
2137 void rt6_age_exceptions(struct fib6_info *f6i,
2138 struct fib6_gc_args *gc_args,
2139 unsigned long now)
2140 {
2141 if (f6i->nh) {
2142 struct fib6_nh_age_excptn_arg arg = {
2143 .gc_args = gc_args,
2144 .now = now
2145 };
2146
2147 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions,
2148 &arg);
2149 } else {
2150 fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now);
2151 }
2152 }
2153
2154 /* must be called with rcu lock held */
2155 int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif,
2156 struct flowi6 *fl6, struct fib6_result *res, int strict)
2157 {
2158 struct fib6_node *fn, *saved_fn;
2159
2160 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2161 saved_fn = fn;
2162
2163 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2164 oif = 0;
2165
2166 redo_rt6_select:
2167 rt6_select(net, fn, oif, res, strict);
2168 if (res->f6i == net->ipv6.fib6_null_entry) {
2169 fn = fib6_backtrack(fn, &fl6->saddr);
2170 if (fn)
2171 goto redo_rt6_select;
2172 else if (strict & RT6_LOOKUP_F_REACHABLE) {
2173 /* also consider unreachable route */
2174 strict &= ~RT6_LOOKUP_F_REACHABLE;
2175 fn = saved_fn;
2176 goto redo_rt6_select;
2177 }
2178 }
2179
2180 trace_fib6_table_lookup(net, res, table, fl6);
2181
2182 return 0;
2183 }
2184
2185 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
2186 int oif, struct flowi6 *fl6,
2187 const struct sk_buff *skb, int flags)
2188 {
2189 struct fib6_result res = {};
2190 struct rt6_info *rt = NULL;
2191 int strict = 0;
2192
2193 WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) &&
2194 !rcu_read_lock_held());
2195
2196 strict |= flags & RT6_LOOKUP_F_IFACE;
2197 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
2198 if (net->ipv6.devconf_all->forwarding == 0)
2199 strict |= RT6_LOOKUP_F_REACHABLE;
2200
2201 rcu_read_lock();
2202
2203 fib6_table_lookup(net, table, oif, fl6, &res, strict);
2204 if (res.f6i == net->ipv6.fib6_null_entry)
2205 goto out;
2206
2207 fib6_select_path(net, &res, fl6, oif, false, skb, strict);
2208
2209 /*Search through exception table */
2210 rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
2211 if (rt) {
2212 goto out;
2213 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
2214 !res.nh->fib_nh_gw_family)) {
2215 /* Create a RTF_CACHE clone which will not be
2216 * owned by the fib6 tree. It is for the special case where
2217 * the daddr in the skb during the neighbor look-up is different
2218 * from the fl6->daddr used to look-up route here.
2219 */
2220 rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL);
2221
2222 if (rt) {
2223 /* 1 refcnt is taken during ip6_rt_cache_alloc().
2224 * As rt6_uncached_list_add() does not consume refcnt,
2225 * this refcnt is always returned to the caller even
2226 * if caller sets RT6_LOOKUP_F_DST_NOREF flag.
2227 */
2228 rt6_uncached_list_add(rt);
2229 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
2230 rcu_read_unlock();
2231
2232 return rt;
2233 }
2234 } else {
2235 /* Get a percpu copy */
2236 local_bh_disable();
2237 rt = rt6_get_pcpu_route(&res);
2238
2239 if (!rt)
2240 rt = rt6_make_pcpu_route(net, &res);
2241
2242 local_bh_enable();
2243 }
2244 out:
2245 if (!rt)
2246 rt = net->ipv6.ip6_null_entry;
2247 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
2248 ip6_hold_safe(net, &rt);
2249 rcu_read_unlock();
2250
2251 return rt;
2252 }
2253 EXPORT_SYMBOL_GPL(ip6_pol_route);
2254
2255 static struct rt6_info *ip6_pol_route_input(struct net *net,
2256 struct fib6_table *table,
2257 struct flowi6 *fl6,
2258 const struct sk_buff *skb,
2259 int flags)
2260 {
2261 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags);
2262 }
2263
2264 struct dst_entry *ip6_route_input_lookup(struct net *net,
2265 struct net_device *dev,
2266 struct flowi6 *fl6,
2267 const struct sk_buff *skb,
2268 int flags)
2269 {
2270 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
2271 flags |= RT6_LOOKUP_F_IFACE;
2272
2273 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input);
2274 }
2275 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
2276
2277 static void ip6_multipath_l3_keys(const struct sk_buff *skb,
2278 struct flow_keys *keys,
2279 struct flow_keys *flkeys)
2280 {
2281 const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
2282 const struct ipv6hdr *key_iph = outer_iph;
2283 struct flow_keys *_flkeys = flkeys;
2284 const struct ipv6hdr *inner_iph;
2285 const struct icmp6hdr *icmph;
2286 struct ipv6hdr _inner_iph;
2287 struct icmp6hdr _icmph;
2288
2289 if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6))
2290 goto out;
2291
2292 icmph = skb_header_pointer(skb, skb_transport_offset(skb),
2293 sizeof(_icmph), &_icmph);
2294 if (!icmph)
2295 goto out;
2296
2297 if (!icmpv6_is_err(icmph->icmp6_type))
2298 goto out;
2299
2300 inner_iph = skb_header_pointer(skb,
2301 skb_transport_offset(skb) + sizeof(*icmph),
2302 sizeof(_inner_iph), &_inner_iph);
2303 if (!inner_iph)
2304 goto out;
2305
2306 key_iph = inner_iph;
2307 _flkeys = NULL;
2308 out:
2309 if (_flkeys) {
2310 keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src;
2311 keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst;
2312 keys->tags.flow_label = _flkeys->tags.flow_label;
2313 keys->basic.ip_proto = _flkeys->basic.ip_proto;
2314 } else {
2315 keys->addrs.v6addrs.src = key_iph->saddr;
2316 keys->addrs.v6addrs.dst = key_iph->daddr;
2317 keys->tags.flow_label = ip6_flowlabel(key_iph);
2318 keys->basic.ip_proto = key_iph->nexthdr;
2319 }
2320 }
2321
2322 /* if skb is set it will be used and fl6 can be NULL */
2323 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
2324 const struct sk_buff *skb, struct flow_keys *flkeys)
2325 {
2326 struct flow_keys hash_keys;
2327 u32 mhash;
2328
2329 switch (ip6_multipath_hash_policy(net)) {
2330 case 0:
2331 memset(&hash_keys, 0, sizeof(hash_keys));
2332 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2333 if (skb) {
2334 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2335 } else {
2336 hash_keys.addrs.v6addrs.src = fl6->saddr;
2337 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2338 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2339 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2340 }
2341 break;
2342 case 1:
2343 if (skb) {
2344 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
2345 struct flow_keys keys;
2346
2347 /* short-circuit if we already have L4 hash present */
2348 if (skb->l4_hash)
2349 return skb_get_hash_raw(skb) >> 1;
2350
2351 memset(&hash_keys, 0, sizeof(hash_keys));
2352
2353 if (!flkeys) {
2354 skb_flow_dissect_flow_keys(skb, &keys, flag);
2355 flkeys = &keys;
2356 }
2357 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2358 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2359 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2360 hash_keys.ports.src = flkeys->ports.src;
2361 hash_keys.ports.dst = flkeys->ports.dst;
2362 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2363 } else {
2364 memset(&hash_keys, 0, sizeof(hash_keys));
2365 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2366 hash_keys.addrs.v6addrs.src = fl6->saddr;
2367 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2368 hash_keys.ports.src = fl6->fl6_sport;
2369 hash_keys.ports.dst = fl6->fl6_dport;
2370 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2371 }
2372 break;
2373 case 2:
2374 memset(&hash_keys, 0, sizeof(hash_keys));
2375 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2376 if (skb) {
2377 struct flow_keys keys;
2378
2379 if (!flkeys) {
2380 skb_flow_dissect_flow_keys(skb, &keys, 0);
2381 flkeys = &keys;
2382 }
2383
2384 /* Inner can be v4 or v6 */
2385 if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
2386 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
2387 hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src;
2388 hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst;
2389 } else if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
2390 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2391 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2392 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2393 hash_keys.tags.flow_label = flkeys->tags.flow_label;
2394 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2395 } else {
2396 /* Same as case 0 */
2397 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2398 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
2399 }
2400 } else {
2401 /* Same as case 0 */
2402 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2403 hash_keys.addrs.v6addrs.src = fl6->saddr;
2404 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2405 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2406 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2407 }
2408 break;
2409 }
2410 mhash = flow_hash_from_keys(&hash_keys);
2411
2412 return mhash >> 1;
2413 }
2414
2415 /* Called with rcu held */
2416 void ip6_route_input(struct sk_buff *skb)
2417 {
2418 const struct ipv6hdr *iph = ipv6_hdr(skb);
2419 struct net *net = dev_net(skb->dev);
2420 int flags = RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_DST_NOREF;
2421 struct ip_tunnel_info *tun_info;
2422 struct flowi6 fl6 = {
2423 .flowi6_iif = skb->dev->ifindex,
2424 .daddr = iph->daddr,
2425 .saddr = iph->saddr,
2426 .flowlabel = ip6_flowinfo(iph),
2427 .flowi6_mark = skb->mark,
2428 .flowi6_proto = iph->nexthdr,
2429 };
2430 struct flow_keys *flkeys = NULL, _flkeys;
2431
2432 tun_info = skb_tunnel_info(skb);
2433 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
2434 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
2435
2436 if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys))
2437 flkeys = &_flkeys;
2438
2439 if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6))
2440 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys);
2441 skb_dst_drop(skb);
2442 skb_dst_set_noref(skb, ip6_route_input_lookup(net, skb->dev,
2443 &fl6, skb, flags));
2444 }
2445
2446 static struct rt6_info *ip6_pol_route_output(struct net *net,
2447 struct fib6_table *table,
2448 struct flowi6 *fl6,
2449 const struct sk_buff *skb,
2450 int flags)
2451 {
2452 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags);
2453 }
2454
2455 struct dst_entry *ip6_route_output_flags_noref(struct net *net,
2456 const struct sock *sk,
2457 struct flowi6 *fl6, int flags)
2458 {
2459 bool any_src;
2460
2461 if (ipv6_addr_type(&fl6->daddr) &
2462 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
2463 struct dst_entry *dst;
2464
2465 /* This function does not take refcnt on the dst */
2466 dst = l3mdev_link_scope_lookup(net, fl6);
2467 if (dst)
2468 return dst;
2469 }
2470
2471 fl6->flowi6_iif = LOOPBACK_IFINDEX;
2472
2473 flags |= RT6_LOOKUP_F_DST_NOREF;
2474 any_src = ipv6_addr_any(&fl6->saddr);
2475 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
2476 (fl6->flowi6_oif && any_src))
2477 flags |= RT6_LOOKUP_F_IFACE;
2478
2479 if (!any_src)
2480 flags |= RT6_LOOKUP_F_HAS_SADDR;
2481 else if (sk)
2482 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
2483
2484 return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
2485 }
2486 EXPORT_SYMBOL_GPL(ip6_route_output_flags_noref);
2487
2488 struct dst_entry *ip6_route_output_flags(struct net *net,
2489 const struct sock *sk,
2490 struct flowi6 *fl6,
2491 int flags)
2492 {
2493 struct dst_entry *dst;
2494 struct rt6_info *rt6;
2495
2496 rcu_read_lock();
2497 dst = ip6_route_output_flags_noref(net, sk, fl6, flags);
2498 rt6 = (struct rt6_info *)dst;
2499 /* For dst cached in uncached_list, refcnt is already taken. */
2500 if (list_empty(&rt6->rt6i_uncached) && !dst_hold_safe(dst)) {
2501 dst = &net->ipv6.ip6_null_entry->dst;
2502 dst_hold(dst);
2503 }
2504 rcu_read_unlock();
2505
2506 return dst;
2507 }
2508 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
2509
2510 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2511 {
2512 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
2513 struct net_device *loopback_dev = net->loopback_dev;
2514 struct dst_entry *new = NULL;
2515
2516 rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, 1,
2517 DST_OBSOLETE_DEAD, 0);
2518 if (rt) {
2519 rt6_info_init(rt);
2520 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
2521
2522 new = &rt->dst;
2523 new->__use = 1;
2524 new->input = dst_discard;
2525 new->output = dst_discard_out;
2526
2527 dst_copy_metrics(new, &ort->dst);
2528
2529 rt->rt6i_idev = in6_dev_get(loopback_dev);
2530 rt->rt6i_gateway = ort->rt6i_gateway;
2531 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
2532
2533 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
2534 #ifdef CONFIG_IPV6_SUBTREES
2535 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
2536 #endif
2537 }
2538
2539 dst_release(dst_orig);
2540 return new ? new : ERR_PTR(-ENOMEM);
2541 }
2542
2543 /*
2544 * Destination cache support functions
2545 */
2546
2547 static bool fib6_check(struct fib6_info *f6i, u32 cookie)
2548 {
2549 u32 rt_cookie = 0;
2550
2551 if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
2552 return false;
2553
2554 if (fib6_check_expired(f6i))
2555 return false;
2556
2557 return true;
2558 }
2559
2560 static struct dst_entry *rt6_check(struct rt6_info *rt,
2561 struct fib6_info *from,
2562 u32 cookie)
2563 {
2564 u32 rt_cookie = 0;
2565
2566 if (!from || !fib6_get_cookie_safe(from, &rt_cookie) ||
2567 rt_cookie != cookie)
2568 return NULL;
2569
2570 if (rt6_check_expired(rt))
2571 return NULL;
2572
2573 return &rt->dst;
2574 }
2575
2576 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
2577 struct fib6_info *from,
2578 u32 cookie)
2579 {
2580 if (!__rt6_check_expired(rt) &&
2581 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
2582 fib6_check(from, cookie))
2583 return &rt->dst;
2584 else
2585 return NULL;
2586 }
2587
2588 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
2589 {
2590 struct dst_entry *dst_ret;
2591 struct fib6_info *from;
2592 struct rt6_info *rt;
2593
2594 rt = container_of(dst, struct rt6_info, dst);
2595
2596 rcu_read_lock();
2597
2598 /* All IPV6 dsts are created with ->obsolete set to the value
2599 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
2600 * into this function always.
2601 */
2602
2603 from = rcu_dereference(rt->from);
2604
2605 if (from && (rt->rt6i_flags & RTF_PCPU ||
2606 unlikely(!list_empty(&rt->rt6i_uncached))))
2607 dst_ret = rt6_dst_from_check(rt, from, cookie);
2608 else
2609 dst_ret = rt6_check(rt, from, cookie);
2610
2611 rcu_read_unlock();
2612
2613 return dst_ret;
2614 }
2615
2616 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
2617 {
2618 struct rt6_info *rt = (struct rt6_info *) dst;
2619
2620 if (rt) {
2621 if (rt->rt6i_flags & RTF_CACHE) {
2622 rcu_read_lock();
2623 if (rt6_check_expired(rt)) {
2624 rt6_remove_exception_rt(rt);
2625 dst = NULL;
2626 }
2627 rcu_read_unlock();
2628 } else {
2629 dst_release(dst);
2630 dst = NULL;
2631 }
2632 }
2633 return dst;
2634 }
2635
2636 static void ip6_link_failure(struct sk_buff *skb)
2637 {
2638 struct rt6_info *rt;
2639
2640 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
2641
2642 rt = (struct rt6_info *) skb_dst(skb);
2643 if (rt) {
2644 rcu_read_lock();
2645 if (rt->rt6i_flags & RTF_CACHE) {
2646 rt6_remove_exception_rt(rt);
2647 } else {
2648 struct fib6_info *from;
2649 struct fib6_node *fn;
2650
2651 from = rcu_dereference(rt->from);
2652 if (from) {
2653 fn = rcu_dereference(from->fib6_node);
2654 if (fn && (rt->rt6i_flags & RTF_DEFAULT))
2655 fn->fn_sernum = -1;
2656 }
2657 }
2658 rcu_read_unlock();
2659 }
2660 }
2661
2662 static void rt6_update_expires(struct rt6_info *rt0, int timeout)
2663 {
2664 if (!(rt0->rt6i_flags & RTF_EXPIRES)) {
2665 struct fib6_info *from;
2666
2667 rcu_read_lock();
2668 from = rcu_dereference(rt0->from);
2669 if (from)
2670 rt0->dst.expires = from->expires;
2671 rcu_read_unlock();
2672 }
2673
2674 dst_set_expires(&rt0->dst, timeout);
2675 rt0->rt6i_flags |= RTF_EXPIRES;
2676 }
2677
2678 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
2679 {
2680 struct net *net = dev_net(rt->dst.dev);
2681
2682 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
2683 rt->rt6i_flags |= RTF_MODIFIED;
2684 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
2685 }
2686
2687 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
2688 {
2689 return !(rt->rt6i_flags & RTF_CACHE) &&
2690 (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from));
2691 }
2692
2693 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
2694 const struct ipv6hdr *iph, u32 mtu,
2695 bool confirm_neigh)
2696 {
2697 const struct in6_addr *daddr, *saddr;
2698 struct rt6_info *rt6 = (struct rt6_info *)dst;
2699
2700 if (dst_metric_locked(dst, RTAX_MTU))
2701 return;
2702
2703 if (iph) {
2704 daddr = &iph->daddr;
2705 saddr = &iph->saddr;
2706 } else if (sk) {
2707 daddr = &sk->sk_v6_daddr;
2708 saddr = &inet6_sk(sk)->saddr;
2709 } else {
2710 daddr = NULL;
2711 saddr = NULL;
2712 }
2713
2714 if (confirm_neigh)
2715 dst_confirm_neigh(dst, daddr);
2716
2717 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
2718 if (mtu >= dst_mtu(dst))
2719 return;
2720
2721 if (!rt6_cache_allowed_for_pmtu(rt6)) {
2722 rt6_do_update_pmtu(rt6, mtu);
2723 /* update rt6_ex->stamp for cache */
2724 if (rt6->rt6i_flags & RTF_CACHE)
2725 rt6_update_exception_stamp_rt(rt6);
2726 } else if (daddr) {
2727 struct fib6_result res = {};
2728 struct rt6_info *nrt6;
2729
2730 rcu_read_lock();
2731 res.f6i = rcu_dereference(rt6->from);
2732 if (!res.f6i)
2733 goto out_unlock;
2734
2735 res.fib6_flags = res.f6i->fib6_flags;
2736 res.fib6_type = res.f6i->fib6_type;
2737
2738 if (res.f6i->nh) {
2739 struct fib6_nh_match_arg arg = {
2740 .dev = dst->dev,
2741 .gw = &rt6->rt6i_gateway,
2742 };
2743
2744 nexthop_for_each_fib6_nh(res.f6i->nh,
2745 fib6_nh_find_match, &arg);
2746
2747 /* fib6_info uses a nexthop that does not have fib6_nh
2748 * using the dst->dev + gw. Should be impossible.
2749 */
2750 if (!arg.match)
2751 goto out_unlock;
2752
2753 res.nh = arg.match;
2754 } else {
2755 res.nh = res.f6i->fib6_nh;
2756 }
2757
2758 nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr);
2759 if (nrt6) {
2760 rt6_do_update_pmtu(nrt6, mtu);
2761 if (rt6_insert_exception(nrt6, &res))
2762 dst_release_immediate(&nrt6->dst);
2763 }
2764 out_unlock:
2765 rcu_read_unlock();
2766 }
2767 }
2768
2769 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
2770 struct sk_buff *skb, u32 mtu,
2771 bool confirm_neigh)
2772 {
2773 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu,
2774 confirm_neigh);
2775 }
2776
2777 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
2778 int oif, u32 mark, kuid_t uid)
2779 {
2780 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2781 struct dst_entry *dst;
2782 struct flowi6 fl6 = {
2783 .flowi6_oif = oif,
2784 .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark),
2785 .daddr = iph->daddr,
2786 .saddr = iph->saddr,
2787 .flowlabel = ip6_flowinfo(iph),
2788 .flowi6_uid = uid,
2789 };
2790
2791 dst = ip6_route_output(net, NULL, &fl6);
2792 if (!dst->error)
2793 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu), true);
2794 dst_release(dst);
2795 }
2796 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
2797
2798 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
2799 {
2800 int oif = sk->sk_bound_dev_if;
2801 struct dst_entry *dst;
2802
2803 if (!oif && skb->dev)
2804 oif = l3mdev_master_ifindex(skb->dev);
2805
2806 ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
2807
2808 dst = __sk_dst_get(sk);
2809 if (!dst || !dst->obsolete ||
2810 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
2811 return;
2812
2813 bh_lock_sock(sk);
2814 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
2815 ip6_datagram_dst_update(sk, false);
2816 bh_unlock_sock(sk);
2817 }
2818 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
2819
2820 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
2821 const struct flowi6 *fl6)
2822 {
2823 #ifdef CONFIG_IPV6_SUBTREES
2824 struct ipv6_pinfo *np = inet6_sk(sk);
2825 #endif
2826
2827 ip6_dst_store(sk, dst,
2828 ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr) ?
2829 &sk->sk_v6_daddr : NULL,
2830 #ifdef CONFIG_IPV6_SUBTREES
2831 ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
2832 &np->saddr :
2833 #endif
2834 NULL);
2835 }
2836
2837 static bool ip6_redirect_nh_match(const struct fib6_result *res,
2838 struct flowi6 *fl6,
2839 const struct in6_addr *gw,
2840 struct rt6_info **ret)
2841 {
2842 const struct fib6_nh *nh = res->nh;
2843
2844 if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
2845 fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
2846 return false;
2847
2848 /* rt_cache's gateway might be different from its 'parent'
2849 * in the case of an ip redirect.
2850 * So we keep searching in the exception table if the gateway
2851 * is different.
2852 */
2853 if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
2854 struct rt6_info *rt_cache;
2855
2856 rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr);
2857 if (rt_cache &&
2858 ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
2859 *ret = rt_cache;
2860 return true;
2861 }
2862 return false;
2863 }
2864 return true;
2865 }
2866
2867 struct fib6_nh_rd_arg {
2868 struct fib6_result *res;
2869 struct flowi6 *fl6;
2870 const struct in6_addr *gw;
2871 struct rt6_info **ret;
2872 };
2873
2874 static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg)
2875 {
2876 struct fib6_nh_rd_arg *arg = _arg;
2877
2878 arg->res->nh = nh;
2879 return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret);
2880 }
2881
2882 /* Handle redirects */
2883 struct ip6rd_flowi {
2884 struct flowi6 fl6;
2885 struct in6_addr gateway;
2886 };
2887
2888 static struct rt6_info *__ip6_route_redirect(struct net *net,
2889 struct fib6_table *table,
2890 struct flowi6 *fl6,
2891 const struct sk_buff *skb,
2892 int flags)
2893 {
2894 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
2895 struct rt6_info *ret = NULL;
2896 struct fib6_result res = {};
2897 struct fib6_nh_rd_arg arg = {
2898 .res = &res,
2899 .fl6 = fl6,
2900 .gw = &rdfl->gateway,
2901 .ret = &ret
2902 };
2903 struct fib6_info *rt;
2904 struct fib6_node *fn;
2905
2906 /* l3mdev_update_flow overrides oif if the device is enslaved; in
2907 * this case we must match on the real ingress device, so reset it
2908 */
2909 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
2910 fl6->flowi6_oif = skb->dev->ifindex;
2911
2912 /* Get the "current" route for this destination and
2913 * check if the redirect has come from appropriate router.
2914 *
2915 * RFC 4861 specifies that redirects should only be
2916 * accepted if they come from the nexthop to the target.
2917 * Due to the way the routes are chosen, this notion
2918 * is a bit fuzzy and one might need to check all possible
2919 * routes.
2920 */
2921
2922 rcu_read_lock();
2923 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2924 restart:
2925 for_each_fib6_node_rt_rcu(fn) {
2926 res.f6i = rt;
2927 if (fib6_check_expired(rt))
2928 continue;
2929 if (rt->fib6_flags & RTF_REJECT)
2930 break;
2931 if (unlikely(rt->nh)) {
2932 if (nexthop_is_blackhole(rt->nh))
2933 continue;
2934 /* on match, res->nh is filled in and potentially ret */
2935 if (nexthop_for_each_fib6_nh(rt->nh,
2936 fib6_nh_redirect_match,
2937 &arg))
2938 goto out;
2939 } else {
2940 res.nh = rt->fib6_nh;
2941 if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway,
2942 &ret))
2943 goto out;
2944 }
2945 }
2946
2947 if (!rt)
2948 rt = net->ipv6.fib6_null_entry;
2949 else if (rt->fib6_flags & RTF_REJECT) {
2950 ret = net->ipv6.ip6_null_entry;
2951 goto out;
2952 }
2953
2954 if (rt == net->ipv6.fib6_null_entry) {
2955 fn = fib6_backtrack(fn, &fl6->saddr);
2956 if (fn)
2957 goto restart;
2958 }
2959
2960 res.f6i = rt;
2961 res.nh = rt->fib6_nh;
2962 out:
2963 if (ret) {
2964 ip6_hold_safe(net, &ret);
2965 } else {
2966 res.fib6_flags = res.f6i->fib6_flags;
2967 res.fib6_type = res.f6i->fib6_type;
2968 ret = ip6_create_rt_rcu(&res);
2969 }
2970
2971 rcu_read_unlock();
2972
2973 trace_fib6_table_lookup(net, &res, table, fl6);
2974 return ret;
2975 };
2976
2977 static struct dst_entry *ip6_route_redirect(struct net *net,
2978 const struct flowi6 *fl6,
2979 const struct sk_buff *skb,
2980 const struct in6_addr *gateway)
2981 {
2982 int flags = RT6_LOOKUP_F_HAS_SADDR;
2983 struct ip6rd_flowi rdfl;
2984
2985 rdfl.fl6 = *fl6;
2986 rdfl.gateway = *gateway;
2987
2988 return fib6_rule_lookup(net, &rdfl.fl6, skb,
2989 flags, __ip6_route_redirect);
2990 }
2991
2992 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
2993 kuid_t uid)
2994 {
2995 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2996 struct dst_entry *dst;
2997 struct flowi6 fl6 = {
2998 .flowi6_iif = LOOPBACK_IFINDEX,
2999 .flowi6_oif = oif,
3000 .flowi6_mark = mark,
3001 .daddr = iph->daddr,
3002 .saddr = iph->saddr,
3003 .flowlabel = ip6_flowinfo(iph),
3004 .flowi6_uid = uid,
3005 };
3006
3007 dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
3008 rt6_do_redirect(dst, NULL, skb);
3009 dst_release(dst);
3010 }
3011 EXPORT_SYMBOL_GPL(ip6_redirect);
3012
3013 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
3014 {
3015 const struct ipv6hdr *iph = ipv6_hdr(skb);
3016 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
3017 struct dst_entry *dst;
3018 struct flowi6 fl6 = {
3019 .flowi6_iif = LOOPBACK_IFINDEX,
3020 .flowi6_oif = oif,
3021 .daddr = msg->dest,
3022 .saddr = iph->daddr,
3023 .flowi6_uid = sock_net_uid(net, NULL),
3024 };
3025
3026 dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
3027 rt6_do_redirect(dst, NULL, skb);
3028 dst_release(dst);
3029 }
3030
3031 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
3032 {
3033 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
3034 sk->sk_uid);
3035 }
3036 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
3037
3038 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
3039 {
3040 struct net_device *dev = dst->dev;
3041 unsigned int mtu = dst_mtu(dst);
3042 struct net *net = dev_net(dev);
3043
3044 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
3045
3046 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
3047 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
3048
3049 /*
3050 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
3051 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
3052 * IPV6_MAXPLEN is also valid and means: "any MSS,
3053 * rely only on pmtu discovery"
3054 */
3055 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
3056 mtu = IPV6_MAXPLEN;
3057 return mtu;
3058 }
3059
3060 static unsigned int ip6_mtu(const struct dst_entry *dst)
3061 {
3062 struct inet6_dev *idev;
3063 unsigned int mtu;
3064
3065 mtu = dst_metric_raw(dst, RTAX_MTU);
3066 if (mtu)
3067 goto out;
3068
3069 mtu = IPV6_MIN_MTU;
3070
3071 rcu_read_lock();
3072 idev = __in6_dev_get(dst->dev);
3073 if (idev)
3074 mtu = idev->cnf.mtu6;
3075 rcu_read_unlock();
3076
3077 out:
3078 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3079
3080 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
3081 }
3082
3083 /* MTU selection:
3084 * 1. mtu on route is locked - use it
3085 * 2. mtu from nexthop exception
3086 * 3. mtu from egress device
3087 *
3088 * based on ip6_dst_mtu_forward and exception logic of
3089 * rt6_find_cached_rt; called with rcu_read_lock
3090 */
3091 u32 ip6_mtu_from_fib6(const struct fib6_result *res,
3092 const struct in6_addr *daddr,
3093 const struct in6_addr *saddr)
3094 {
3095 const struct fib6_nh *nh = res->nh;
3096 struct fib6_info *f6i = res->f6i;
3097 struct inet6_dev *idev;
3098 struct rt6_info *rt;
3099 u32 mtu = 0;
3100
3101 if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
3102 mtu = f6i->fib6_pmtu;
3103 if (mtu)
3104 goto out;
3105 }
3106
3107 rt = rt6_find_cached_rt(res, daddr, saddr);
3108 if (unlikely(rt)) {
3109 mtu = dst_metric_raw(&rt->dst, RTAX_MTU);
3110 } else {
3111 struct net_device *dev = nh->fib_nh_dev;
3112
3113 mtu = IPV6_MIN_MTU;
3114 idev = __in6_dev_get(dev);
3115 if (idev && idev->cnf.mtu6 > mtu)
3116 mtu = idev->cnf.mtu6;
3117 }
3118
3119 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
3120 out:
3121 return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
3122 }
3123
3124 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
3125 struct flowi6 *fl6)
3126 {
3127 struct dst_entry *dst;
3128 struct rt6_info *rt;
3129 struct inet6_dev *idev = in6_dev_get(dev);
3130 struct net *net = dev_net(dev);
3131
3132 if (unlikely(!idev))
3133 return ERR_PTR(-ENODEV);
3134
3135 rt = ip6_dst_alloc(net, dev, 0);
3136 if (unlikely(!rt)) {
3137 in6_dev_put(idev);
3138 dst = ERR_PTR(-ENOMEM);
3139 goto out;
3140 }
3141
3142 rt->dst.input = ip6_input;
3143 rt->dst.output = ip6_output;
3144 rt->rt6i_gateway = fl6->daddr;
3145 rt->rt6i_dst.addr = fl6->daddr;
3146 rt->rt6i_dst.plen = 128;
3147 rt->rt6i_idev = idev;
3148 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
3149
3150 /* Add this dst into uncached_list so that rt6_disable_ip() can
3151 * do proper release of the net_device
3152 */
3153 rt6_uncached_list_add(rt);
3154 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
3155
3156 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
3157
3158 out:
3159 return dst;
3160 }
3161
3162 static int ip6_dst_gc(struct dst_ops *ops)
3163 {
3164 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
3165 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
3166 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
3167 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
3168 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
3169 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
3170 int entries;
3171
3172 entries = dst_entries_get_fast(ops);
3173 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
3174 entries <= rt_max_size)
3175 goto out;
3176
3177 net->ipv6.ip6_rt_gc_expire++;
3178 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
3179 entries = dst_entries_get_slow(ops);
3180 if (entries < ops->gc_thresh)
3181 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
3182 out:
3183 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
3184 return entries > rt_max_size;
3185 }
3186
3187 static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
3188 const struct in6_addr *gw_addr, u32 tbid,
3189 int flags, struct fib6_result *res)
3190 {
3191 struct flowi6 fl6 = {
3192 .flowi6_oif = cfg->fc_ifindex,
3193 .daddr = *gw_addr,
3194 .saddr = cfg->fc_prefsrc,
3195 };
3196 struct fib6_table *table;
3197 int err;
3198
3199 table = fib6_get_table(net, tbid);
3200 if (!table)
3201 return -EINVAL;
3202
3203 if (!ipv6_addr_any(&cfg->fc_prefsrc))
3204 flags |= RT6_LOOKUP_F_HAS_SADDR;
3205
3206 flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
3207
3208 err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags);
3209 if (!err && res->f6i != net->ipv6.fib6_null_entry)
3210 fib6_select_path(net, res, &fl6, cfg->fc_ifindex,
3211 cfg->fc_ifindex != 0, NULL, flags);
3212
3213 return err;
3214 }
3215
3216 static int ip6_route_check_nh_onlink(struct net *net,
3217 struct fib6_config *cfg,
3218 const struct net_device *dev,
3219 struct netlink_ext_ack *extack)
3220 {
3221 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
3222 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3223 struct fib6_result res = {};
3224 int err;
3225
3226 err = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0, &res);
3227 if (!err && !(res.fib6_flags & RTF_REJECT) &&
3228 /* ignore match if it is the default route */
3229 !ipv6_addr_any(&res.f6i->fib6_dst.addr) &&
3230 (res.fib6_type != RTN_UNICAST || dev != res.nh->fib_nh_dev)) {
3231 NL_SET_ERR_MSG(extack,
3232 "Nexthop has invalid gateway or device mismatch");
3233 err = -EINVAL;
3234 }
3235
3236 return err;
3237 }
3238
3239 static int ip6_route_check_nh(struct net *net,
3240 struct fib6_config *cfg,
3241 struct net_device **_dev,
3242 struct inet6_dev **idev)
3243 {
3244 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3245 struct net_device *dev = _dev ? *_dev : NULL;
3246 int flags = RT6_LOOKUP_F_IFACE;
3247 struct fib6_result res = {};
3248 int err = -EHOSTUNREACH;
3249
3250 if (cfg->fc_table) {
3251 err = ip6_nh_lookup_table(net, cfg, gw_addr,
3252 cfg->fc_table, flags, &res);
3253 /* gw_addr can not require a gateway or resolve to a reject
3254 * route. If a device is given, it must match the result.
3255 */
3256 if (err || res.fib6_flags & RTF_REJECT ||
3257 res.nh->fib_nh_gw_family ||
3258 (dev && dev != res.nh->fib_nh_dev))
3259 err = -EHOSTUNREACH;
3260 }
3261
3262 if (err < 0) {
3263 struct flowi6 fl6 = {
3264 .flowi6_oif = cfg->fc_ifindex,
3265 .daddr = *gw_addr,
3266 };
3267
3268 err = fib6_lookup(net, cfg->fc_ifindex, &fl6, &res, flags);
3269 if (err || res.fib6_flags & RTF_REJECT ||
3270 res.nh->fib_nh_gw_family)
3271 err = -EHOSTUNREACH;
3272
3273 if (err)
3274 return err;
3275
3276 fib6_select_path(net, &res, &fl6, cfg->fc_ifindex,
3277 cfg->fc_ifindex != 0, NULL, flags);
3278 }
3279
3280 err = 0;
3281 if (dev) {
3282 if (dev != res.nh->fib_nh_dev)
3283 err = -EHOSTUNREACH;
3284 } else {
3285 *_dev = dev = res.nh->fib_nh_dev;
3286 dev_hold(dev);
3287 *idev = in6_dev_get(dev);
3288 }
3289
3290 return err;
3291 }
3292
3293 static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
3294 struct net_device **_dev, struct inet6_dev **idev,
3295 struct netlink_ext_ack *extack)
3296 {
3297 const struct in6_addr *gw_addr = &cfg->fc_gateway;
3298 int gwa_type = ipv6_addr_type(gw_addr);
3299 bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
3300 const struct net_device *dev = *_dev;
3301 bool need_addr_check = !dev;
3302 int err = -EINVAL;
3303
3304 /* if gw_addr is local we will fail to detect this in case
3305 * address is still TENTATIVE (DAD in progress). rt6_lookup()
3306 * will return already-added prefix route via interface that
3307 * prefix route was assigned to, which might be non-loopback.
3308 */
3309 if (dev &&
3310 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3311 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3312 goto out;
3313 }
3314
3315 if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
3316 /* IPv6 strictly inhibits using not link-local
3317 * addresses as nexthop address.
3318 * Otherwise, router will not able to send redirects.
3319 * It is very good, but in some (rare!) circumstances
3320 * (SIT, PtP, NBMA NOARP links) it is handy to allow
3321 * some exceptions. --ANK
3322 * We allow IPv4-mapped nexthops to support RFC4798-type
3323 * addressing
3324 */
3325 if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
3326 NL_SET_ERR_MSG(extack, "Invalid gateway address");
3327 goto out;
3328 }
3329
3330 rcu_read_lock();
3331
3332 if (cfg->fc_flags & RTNH_F_ONLINK)
3333 err = ip6_route_check_nh_onlink(net, cfg, dev, extack);
3334 else
3335 err = ip6_route_check_nh(net, cfg, _dev, idev);
3336
3337 rcu_read_unlock();
3338
3339 if (err)
3340 goto out;
3341 }
3342
3343 /* reload in case device was changed */
3344 dev = *_dev;
3345
3346 err = -EINVAL;
3347 if (!dev) {
3348 NL_SET_ERR_MSG(extack, "Egress device not specified");
3349 goto out;
3350 } else if (dev->flags & IFF_LOOPBACK) {
3351 NL_SET_ERR_MSG(extack,
3352 "Egress device can not be loopback device for this route");
3353 goto out;
3354 }
3355
3356 /* if we did not check gw_addr above, do so now that the
3357 * egress device has been resolved.
3358 */
3359 if (need_addr_check &&
3360 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
3361 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
3362 goto out;
3363 }
3364
3365 err = 0;
3366 out:
3367 return err;
3368 }
3369
3370 static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type)
3371 {
3372 if ((flags & RTF_REJECT) ||
3373 (dev && (dev->flags & IFF_LOOPBACK) &&
3374 !(addr_type & IPV6_ADDR_LOOPBACK) &&
3375 !(flags & RTF_LOCAL)))
3376 return true;
3377
3378 return false;
3379 }
3380
3381 int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
3382 struct fib6_config *cfg, gfp_t gfp_flags,
3383 struct netlink_ext_ack *extack)
3384 {
3385 struct net_device *dev = NULL;
3386 struct inet6_dev *idev = NULL;
3387 int addr_type;
3388 int err;
3389
3390 fib6_nh->fib_nh_family = AF_INET6;
3391 #ifdef CONFIG_IPV6_ROUTER_PREF
3392 fib6_nh->last_probe = jiffies;
3393 #endif
3394
3395 err = -ENODEV;
3396 if (cfg->fc_ifindex) {
3397 dev = dev_get_by_index(net, cfg->fc_ifindex);
3398 if (!dev)
3399 goto out;
3400 idev = in6_dev_get(dev);
3401 if (!idev)
3402 goto out;
3403 }
3404
3405 if (cfg->fc_flags & RTNH_F_ONLINK) {
3406 if (!dev) {
3407 NL_SET_ERR_MSG(extack,
3408 "Nexthop device required for onlink");
3409 goto out;
3410 }
3411
3412 if (!(dev->flags & IFF_UP)) {
3413 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3414 err = -ENETDOWN;
3415 goto out;
3416 }
3417
3418 fib6_nh->fib_nh_flags |= RTNH_F_ONLINK;
3419 }
3420
3421 fib6_nh->fib_nh_weight = 1;
3422
3423 /* We cannot add true routes via loopback here,
3424 * they would result in kernel looping; promote them to reject routes
3425 */
3426 addr_type = ipv6_addr_type(&cfg->fc_dst);
3427 if (fib6_is_reject(cfg->fc_flags, dev, addr_type)) {
3428 /* hold loopback dev/idev if we haven't done so. */
3429 if (dev != net->loopback_dev) {
3430 if (dev) {
3431 dev_put(dev);
3432 in6_dev_put(idev);
3433 }
3434 dev = net->loopback_dev;
3435 dev_hold(dev);
3436 idev = in6_dev_get(dev);
3437 if (!idev) {
3438 err = -ENODEV;
3439 goto out;
3440 }
3441 }
3442 goto pcpu_alloc;
3443 }
3444
3445 if (cfg->fc_flags & RTF_GATEWAY) {
3446 err = ip6_validate_gw(net, cfg, &dev, &idev, extack);
3447 if (err)
3448 goto out;
3449
3450 fib6_nh->fib_nh_gw6 = cfg->fc_gateway;
3451 fib6_nh->fib_nh_gw_family = AF_INET6;
3452 }
3453
3454 err = -ENODEV;
3455 if (!dev)
3456 goto out;
3457
3458 if (idev->cnf.disable_ipv6) {
3459 NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
3460 err = -EACCES;
3461 goto out;
3462 }
3463
3464 if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) {
3465 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3466 err = -ENETDOWN;
3467 goto out;
3468 }
3469
3470 if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
3471 !netif_carrier_ok(dev))
3472 fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
3473
3474 err = fib_nh_common_init(net, &fib6_nh->nh_common, cfg->fc_encap,
3475 cfg->fc_encap_type, cfg, gfp_flags, extack);
3476 if (err)
3477 goto out;
3478
3479 pcpu_alloc:
3480 fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags);
3481 if (!fib6_nh->rt6i_pcpu) {
3482 err = -ENOMEM;
3483 goto out;
3484 }
3485
3486 fib6_nh->fib_nh_dev = dev;
3487 fib6_nh->fib_nh_oif = dev->ifindex;
3488 err = 0;
3489 out:
3490 if (idev)
3491 in6_dev_put(idev);
3492
3493 if (err) {
3494 lwtstate_put(fib6_nh->fib_nh_lws);
3495 fib6_nh->fib_nh_lws = NULL;
3496 if (dev)
3497 dev_put(dev);
3498 }
3499
3500 return err;
3501 }
3502
3503 void fib6_nh_release(struct fib6_nh *fib6_nh)
3504 {
3505 struct rt6_exception_bucket *bucket;
3506
3507 rcu_read_lock();
3508
3509 fib6_nh_flush_exceptions(fib6_nh, NULL);
3510 bucket = fib6_nh_get_excptn_bucket(fib6_nh, NULL);
3511 if (bucket) {
3512 rcu_assign_pointer(fib6_nh->rt6i_exception_bucket, NULL);
3513 kfree(bucket);
3514 }
3515
3516 rcu_read_unlock();
3517
3518 if (fib6_nh->rt6i_pcpu) {
3519 int cpu;
3520
3521 for_each_possible_cpu(cpu) {
3522 struct rt6_info **ppcpu_rt;
3523 struct rt6_info *pcpu_rt;
3524
3525 ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu);
3526 pcpu_rt = *ppcpu_rt;
3527 if (pcpu_rt) {
3528 dst_dev_put(&pcpu_rt->dst);
3529 dst_release(&pcpu_rt->dst);
3530 *ppcpu_rt = NULL;
3531 }
3532 }
3533
3534 free_percpu(fib6_nh->rt6i_pcpu);
3535 }
3536
3537 fib_nh_common_release(&fib6_nh->nh_common);
3538 }
3539
3540 static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
3541 gfp_t gfp_flags,
3542 struct netlink_ext_ack *extack)
3543 {
3544 struct net *net = cfg->fc_nlinfo.nl_net;
3545 struct fib6_info *rt = NULL;
3546 struct nexthop *nh = NULL;
3547 struct fib6_table *table;
3548 struct fib6_nh *fib6_nh;
3549 int err = -EINVAL;
3550 int addr_type;
3551
3552 /* RTF_PCPU is an internal flag; can not be set by userspace */
3553 if (cfg->fc_flags & RTF_PCPU) {
3554 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
3555 goto out;
3556 }
3557
3558 /* RTF_CACHE is an internal flag; can not be set by userspace */
3559 if (cfg->fc_flags & RTF_CACHE) {
3560 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
3561 goto out;
3562 }
3563
3564 if (cfg->fc_type > RTN_MAX) {
3565 NL_SET_ERR_MSG(extack, "Invalid route type");
3566 goto out;
3567 }
3568
3569 if (cfg->fc_dst_len > 128) {
3570 NL_SET_ERR_MSG(extack, "Invalid prefix length");
3571 goto out;
3572 }
3573 if (cfg->fc_src_len > 128) {
3574 NL_SET_ERR_MSG(extack, "Invalid source address length");
3575 goto out;
3576 }
3577 #ifndef CONFIG_IPV6_SUBTREES
3578 if (cfg->fc_src_len) {
3579 NL_SET_ERR_MSG(extack,
3580 "Specifying source address requires IPV6_SUBTREES to be enabled");
3581 goto out;
3582 }
3583 #endif
3584 if (cfg->fc_nh_id) {
3585 nh = nexthop_find_by_id(net, cfg->fc_nh_id);
3586 if (!nh) {
3587 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
3588 goto out;
3589 }
3590 err = fib6_check_nexthop(nh, cfg, extack);
3591 if (err)
3592 goto out;
3593 }
3594
3595 err = -ENOBUFS;
3596 if (cfg->fc_nlinfo.nlh &&
3597 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
3598 table = fib6_get_table(net, cfg->fc_table);
3599 if (!table) {
3600 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
3601 table = fib6_new_table(net, cfg->fc_table);
3602 }
3603 } else {
3604 table = fib6_new_table(net, cfg->fc_table);
3605 }
3606
3607 if (!table)
3608 goto out;
3609
3610 err = -ENOMEM;
3611 rt = fib6_info_alloc(gfp_flags, !nh);
3612 if (!rt)
3613 goto out;
3614
3615 rt->fib6_metrics = ip_fib_metrics_init(net, cfg->fc_mx, cfg->fc_mx_len,
3616 extack);
3617 if (IS_ERR(rt->fib6_metrics)) {
3618 err = PTR_ERR(rt->fib6_metrics);
3619 /* Do not leave garbage there. */
3620 rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
3621 goto out;
3622 }
3623
3624 if (cfg->fc_flags & RTF_ADDRCONF)
3625 rt->dst_nocount = true;
3626
3627 if (cfg->fc_flags & RTF_EXPIRES)
3628 fib6_set_expires(rt, jiffies +
3629 clock_t_to_jiffies(cfg->fc_expires));
3630 else
3631 fib6_clean_expires(rt);
3632
3633 if (cfg->fc_protocol == RTPROT_UNSPEC)
3634 cfg->fc_protocol = RTPROT_BOOT;
3635 rt->fib6_protocol = cfg->fc_protocol;
3636
3637 rt->fib6_table = table;
3638 rt->fib6_metric = cfg->fc_metric;
3639 rt->fib6_type = cfg->fc_type ? : RTN_UNICAST;
3640 rt->fib6_flags = cfg->fc_flags & ~RTF_GATEWAY;
3641
3642 ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
3643 rt->fib6_dst.plen = cfg->fc_dst_len;
3644
3645 #ifdef CONFIG_IPV6_SUBTREES
3646 ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3647 rt->fib6_src.plen = cfg->fc_src_len;
3648 #endif
3649 if (nh) {
3650 if (!nexthop_get(nh)) {
3651 NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
3652 goto out;
3653 }
3654 if (rt->fib6_src.plen) {
3655 NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
3656 goto out;
3657 }
3658 rt->nh = nh;
3659 fib6_nh = nexthop_fib6_nh(rt->nh);
3660 } else {
3661 err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
3662 if (err)
3663 goto out;
3664
3665 fib6_nh = rt->fib6_nh;
3666
3667 /* We cannot add true routes via loopback here, they would
3668 * result in kernel looping; promote them to reject routes
3669 */
3670 addr_type = ipv6_addr_type(&cfg->fc_dst);
3671 if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev,
3672 addr_type))
3673 rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP;
3674 }
3675
3676 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
3677 struct net_device *dev = fib6_nh->fib_nh_dev;
3678
3679 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3680 NL_SET_ERR_MSG(extack, "Invalid source address");
3681 err = -EINVAL;
3682 goto out;
3683 }
3684 rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3685 rt->fib6_prefsrc.plen = 128;
3686 } else
3687 rt->fib6_prefsrc.plen = 0;
3688
3689 return rt;
3690 out:
3691 fib6_info_release(rt);
3692 return ERR_PTR(err);
3693 }
3694
3695 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
3696 struct netlink_ext_ack *extack)
3697 {
3698 struct fib6_info *rt;
3699 int err;
3700
3701 rt = ip6_route_info_create(cfg, gfp_flags, extack);
3702 if (IS_ERR(rt))
3703 return PTR_ERR(rt);
3704
3705 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3706 fib6_info_release(rt);
3707
3708 return err;
3709 }
3710
3711 static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
3712 {
3713 struct net *net = info->nl_net;
3714 struct fib6_table *table;
3715 int err;
3716
3717 if (rt == net->ipv6.fib6_null_entry) {
3718 err = -ENOENT;
3719 goto out;
3720 }
3721
3722 table = rt->fib6_table;
3723 spin_lock_bh(&table->tb6_lock);
3724 err = fib6_del(rt, info);
3725 spin_unlock_bh(&table->tb6_lock);
3726
3727 out:
3728 fib6_info_release(rt);
3729 return err;
3730 }
3731
3732 int ip6_del_rt(struct net *net, struct fib6_info *rt)
3733 {
3734 struct nl_info info = { .nl_net = net };
3735
3736 return __ip6_del_rt(rt, &info);
3737 }
3738
3739 static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
3740 {
3741 struct nl_info *info = &cfg->fc_nlinfo;
3742 struct net *net = info->nl_net;
3743 struct sk_buff *skb = NULL;
3744 struct fib6_table *table;
3745 int err = -ENOENT;
3746
3747 if (rt == net->ipv6.fib6_null_entry)
3748 goto out_put;
3749 table = rt->fib6_table;
3750 spin_lock_bh(&table->tb6_lock);
3751
3752 if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
3753 struct fib6_info *sibling, *next_sibling;
3754 struct fib6_node *fn;
3755
3756 /* prefer to send a single notification with all hops */
3757 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3758 if (skb) {
3759 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3760
3761 if (rt6_fill_node(net, skb, rt, NULL,
3762 NULL, NULL, 0, RTM_DELROUTE,
3763 info->portid, seq, 0) < 0) {
3764 kfree_skb(skb);
3765 skb = NULL;
3766 } else
3767 info->skip_notify = 1;
3768 }
3769
3770 /* 'rt' points to the first sibling route. If it is not the
3771 * leaf, then we do not need to send a notification. Otherwise,
3772 * we need to check if the last sibling has a next route or not
3773 * and emit a replace or delete notification, respectively.
3774 */
3775 info->skip_notify_kernel = 1;
3776 fn = rcu_dereference_protected(rt->fib6_node,
3777 lockdep_is_held(&table->tb6_lock));
3778 if (rcu_access_pointer(fn->leaf) == rt) {
3779 struct fib6_info *last_sibling, *replace_rt;
3780
3781 last_sibling = list_last_entry(&rt->fib6_siblings,
3782 struct fib6_info,
3783 fib6_siblings);
3784 replace_rt = rcu_dereference_protected(
3785 last_sibling->fib6_next,
3786 lockdep_is_held(&table->tb6_lock));
3787 if (replace_rt)
3788 call_fib6_entry_notifiers_replace(net,
3789 replace_rt);
3790 else
3791 call_fib6_multipath_entry_notifiers(net,
3792 FIB_EVENT_ENTRY_DEL,
3793 rt, rt->fib6_nsiblings,
3794 NULL);
3795 }
3796 list_for_each_entry_safe(sibling, next_sibling,
3797 &rt->fib6_siblings,
3798 fib6_siblings) {
3799 err = fib6_del(sibling, info);
3800 if (err)
3801 goto out_unlock;
3802 }
3803 }
3804
3805 err = fib6_del(rt, info);
3806 out_unlock:
3807 spin_unlock_bh(&table->tb6_lock);
3808 out_put:
3809 fib6_info_release(rt);
3810
3811 if (skb) {
3812 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3813 info->nlh, gfp_any());
3814 }
3815 return err;
3816 }
3817
3818 static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
3819 {
3820 int rc = -ESRCH;
3821
3822 if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
3823 goto out;
3824
3825 if (cfg->fc_flags & RTF_GATEWAY &&
3826 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
3827 goto out;
3828
3829 rc = rt6_remove_exception_rt(rt);
3830 out:
3831 return rc;
3832 }
3833
3834 static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt,
3835 struct fib6_nh *nh)
3836 {
3837 struct fib6_result res = {
3838 .f6i = rt,
3839 .nh = nh,
3840 };
3841 struct rt6_info *rt_cache;
3842
3843 rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src);
3844 if (rt_cache)
3845 return __ip6_del_cached_rt(rt_cache, cfg);
3846
3847 return 0;
3848 }
3849
3850 struct fib6_nh_del_cached_rt_arg {
3851 struct fib6_config *cfg;
3852 struct fib6_info *f6i;
3853 };
3854
3855 static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg)
3856 {
3857 struct fib6_nh_del_cached_rt_arg *arg = _arg;
3858 int rc;
3859
3860 rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh);
3861 return rc != -ESRCH ? rc : 0;
3862 }
3863
3864 static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i)
3865 {
3866 struct fib6_nh_del_cached_rt_arg arg = {
3867 .cfg = cfg,
3868 .f6i = f6i
3869 };
3870
3871 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg);
3872 }
3873
3874 static int ip6_route_del(struct fib6_config *cfg,
3875 struct netlink_ext_ack *extack)
3876 {
3877 struct fib6_table *table;
3878 struct fib6_info *rt;
3879 struct fib6_node *fn;
3880 int err = -ESRCH;
3881
3882 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
3883 if (!table) {
3884 NL_SET_ERR_MSG(extack, "FIB table does not exist");
3885 return err;
3886 }
3887
3888 rcu_read_lock();
3889
3890 fn = fib6_locate(&table->tb6_root,
3891 &cfg->fc_dst, cfg->fc_dst_len,
3892 &cfg->fc_src, cfg->fc_src_len,
3893 !(cfg->fc_flags & RTF_CACHE));
3894
3895 if (fn) {
3896 for_each_fib6_node_rt_rcu(fn) {
3897 struct fib6_nh *nh;
3898
3899 if (rt->nh && cfg->fc_nh_id &&
3900 rt->nh->id != cfg->fc_nh_id)
3901 continue;
3902
3903 if (cfg->fc_flags & RTF_CACHE) {
3904 int rc = 0;
3905
3906 if (rt->nh) {
3907 rc = ip6_del_cached_rt_nh(cfg, rt);
3908 } else if (cfg->fc_nh_id) {
3909 continue;
3910 } else {
3911 nh = rt->fib6_nh;
3912 rc = ip6_del_cached_rt(cfg, rt, nh);
3913 }
3914 if (rc != -ESRCH) {
3915 rcu_read_unlock();
3916 return rc;
3917 }
3918 continue;
3919 }
3920
3921 if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
3922 continue;
3923 if (cfg->fc_protocol &&
3924 cfg->fc_protocol != rt->fib6_protocol)
3925 continue;
3926
3927 if (rt->nh) {
3928 if (!fib6_info_hold_safe(rt))
3929 continue;
3930 rcu_read_unlock();
3931
3932 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3933 }
3934 if (cfg->fc_nh_id)
3935 continue;
3936
3937 nh = rt->fib6_nh;
3938 if (cfg->fc_ifindex &&
3939 (!nh->fib_nh_dev ||
3940 nh->fib_nh_dev->ifindex != cfg->fc_ifindex))
3941 continue;
3942 if (cfg->fc_flags & RTF_GATEWAY &&
3943 !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6))
3944 continue;
3945 if (!fib6_info_hold_safe(rt))
3946 continue;
3947 rcu_read_unlock();
3948
3949 /* if gateway was specified only delete the one hop */
3950 if (cfg->fc_flags & RTF_GATEWAY)
3951 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3952
3953 return __ip6_del_rt_siblings(rt, cfg);
3954 }
3955 }
3956 rcu_read_unlock();
3957
3958 return err;
3959 }
3960
3961 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
3962 {
3963 struct netevent_redirect netevent;
3964 struct rt6_info *rt, *nrt = NULL;
3965 struct fib6_result res = {};
3966 struct ndisc_options ndopts;
3967 struct inet6_dev *in6_dev;
3968 struct neighbour *neigh;
3969 struct rd_msg *msg;
3970 int optlen, on_link;
3971 u8 *lladdr;
3972
3973 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
3974 optlen -= sizeof(*msg);
3975
3976 if (optlen < 0) {
3977 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
3978 return;
3979 }
3980
3981 msg = (struct rd_msg *)icmp6_hdr(skb);
3982
3983 if (ipv6_addr_is_multicast(&msg->dest)) {
3984 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
3985 return;
3986 }
3987
3988 on_link = 0;
3989 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
3990 on_link = 1;
3991 } else if (ipv6_addr_type(&msg->target) !=
3992 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
3993 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
3994 return;
3995 }
3996
3997 in6_dev = __in6_dev_get(skb->dev);
3998 if (!in6_dev)
3999 return;
4000 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
4001 return;
4002
4003 /* RFC2461 8.1:
4004 * The IP source address of the Redirect MUST be the same as the current
4005 * first-hop router for the specified ICMP Destination Address.
4006 */
4007
4008 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
4009 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
4010 return;
4011 }
4012
4013 lladdr = NULL;
4014 if (ndopts.nd_opts_tgt_lladdr) {
4015 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
4016 skb->dev);
4017 if (!lladdr) {
4018 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
4019 return;
4020 }
4021 }
4022
4023 rt = (struct rt6_info *) dst;
4024 if (rt->rt6i_flags & RTF_REJECT) {
4025 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
4026 return;
4027 }
4028
4029 /* Redirect received -> path was valid.
4030 * Look, redirects are sent only in response to data packets,
4031 * so that this nexthop apparently is reachable. --ANK
4032 */
4033 dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
4034
4035 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
4036 if (!neigh)
4037 return;
4038
4039 /*
4040 * We have finally decided to accept it.
4041 */
4042
4043 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
4044 NEIGH_UPDATE_F_WEAK_OVERRIDE|
4045 NEIGH_UPDATE_F_OVERRIDE|
4046 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
4047 NEIGH_UPDATE_F_ISROUTER)),
4048 NDISC_REDIRECT, &ndopts);
4049
4050 rcu_read_lock();
4051 res.f6i = rcu_dereference(rt->from);
4052 if (!res.f6i)
4053 goto out;
4054
4055 if (res.f6i->nh) {
4056 struct fib6_nh_match_arg arg = {
4057 .dev = dst->dev,
4058 .gw = &rt->rt6i_gateway,
4059 };
4060
4061 nexthop_for_each_fib6_nh(res.f6i->nh,
4062 fib6_nh_find_match, &arg);
4063
4064 /* fib6_info uses a nexthop that does not have fib6_nh
4065 * using the dst->dev. Should be impossible
4066 */
4067 if (!arg.match)
4068 goto out;
4069 res.nh = arg.match;
4070 } else {
4071 res.nh = res.f6i->fib6_nh;
4072 }
4073
4074 res.fib6_flags = res.f6i->fib6_flags;
4075 res.fib6_type = res.f6i->fib6_type;
4076 nrt = ip6_rt_cache_alloc(&res, &msg->dest, NULL);
4077 if (!nrt)
4078 goto out;
4079
4080 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
4081 if (on_link)
4082 nrt->rt6i_flags &= ~RTF_GATEWAY;
4083
4084 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
4085
4086 /* rt6_insert_exception() will take care of duplicated exceptions */
4087 if (rt6_insert_exception(nrt, &res)) {
4088 dst_release_immediate(&nrt->dst);
4089 goto out;
4090 }
4091
4092 netevent.old = &rt->dst;
4093 netevent.new = &nrt->dst;
4094 netevent.daddr = &msg->dest;
4095 netevent.neigh = neigh;
4096 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
4097
4098 out:
4099 rcu_read_unlock();
4100 neigh_release(neigh);
4101 }
4102
4103 #ifdef CONFIG_IPV6_ROUTE_INFO
4104 static struct fib6_info *rt6_get_route_info(struct net *net,
4105 const struct in6_addr *prefix, int prefixlen,
4106 const struct in6_addr *gwaddr,
4107 struct net_device *dev)
4108 {
4109 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
4110 int ifindex = dev->ifindex;
4111 struct fib6_node *fn;
4112 struct fib6_info *rt = NULL;
4113 struct fib6_table *table;
4114
4115 table = fib6_get_table(net, tb_id);
4116 if (!table)
4117 return NULL;
4118
4119 rcu_read_lock();
4120 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
4121 if (!fn)
4122 goto out;
4123
4124 for_each_fib6_node_rt_rcu(fn) {
4125 /* these routes do not use nexthops */
4126 if (rt->nh)
4127 continue;
4128 if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex)
4129 continue;
4130 if (!(rt->fib6_flags & RTF_ROUTEINFO) ||
4131 !rt->fib6_nh->fib_nh_gw_family)
4132 continue;
4133 if (!ipv6_addr_equal(&rt->fib6_nh->fib_nh_gw6, gwaddr))
4134 continue;
4135 if (!fib6_info_hold_safe(rt))
4136 continue;
4137 break;
4138 }
4139 out:
4140 rcu_read_unlock();
4141 return rt;
4142 }
4143
4144 static struct fib6_info *rt6_add_route_info(struct net *net,
4145 const struct in6_addr *prefix, int prefixlen,
4146 const struct in6_addr *gwaddr,
4147 struct net_device *dev,
4148 unsigned int pref)
4149 {
4150 struct fib6_config cfg = {
4151 .fc_metric = IP6_RT_PRIO_USER,
4152 .fc_ifindex = dev->ifindex,
4153 .fc_dst_len = prefixlen,
4154 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
4155 RTF_UP | RTF_PREF(pref),
4156 .fc_protocol = RTPROT_RA,
4157 .fc_type = RTN_UNICAST,
4158 .fc_nlinfo.portid = 0,
4159 .fc_nlinfo.nlh = NULL,
4160 .fc_nlinfo.nl_net = net,
4161 };
4162
4163 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
4164 cfg.fc_dst = *prefix;
4165 cfg.fc_gateway = *gwaddr;
4166
4167 /* We should treat it as a default route if prefix length is 0. */
4168 if (!prefixlen)
4169 cfg.fc_flags |= RTF_DEFAULT;
4170
4171 ip6_route_add(&cfg, GFP_ATOMIC, NULL);
4172
4173 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
4174 }
4175 #endif
4176
4177 struct fib6_info *rt6_get_dflt_router(struct net *net,
4178 const struct in6_addr *addr,
4179 struct net_device *dev)
4180 {
4181 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
4182 struct fib6_info *rt;
4183 struct fib6_table *table;
4184
4185 table = fib6_get_table(net, tb_id);
4186 if (!table)
4187 return NULL;
4188
4189 rcu_read_lock();
4190 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4191 struct fib6_nh *nh;
4192
4193 /* RA routes do not use nexthops */
4194 if (rt->nh)
4195 continue;
4196
4197 nh = rt->fib6_nh;
4198 if (dev == nh->fib_nh_dev &&
4199 ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
4200 ipv6_addr_equal(&nh->fib_nh_gw6, addr))
4201 break;
4202 }
4203 if (rt && !fib6_info_hold_safe(rt))
4204 rt = NULL;
4205 rcu_read_unlock();
4206 return rt;
4207 }
4208
4209 struct fib6_info *rt6_add_dflt_router(struct net *net,
4210 const struct in6_addr *gwaddr,
4211 struct net_device *dev,
4212 unsigned int pref)
4213 {
4214 struct fib6_config cfg = {
4215 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
4216 .fc_metric = IP6_RT_PRIO_USER,
4217 .fc_ifindex = dev->ifindex,
4218 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
4219 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
4220 .fc_protocol = RTPROT_RA,
4221 .fc_type = RTN_UNICAST,
4222 .fc_nlinfo.portid = 0,
4223 .fc_nlinfo.nlh = NULL,
4224 .fc_nlinfo.nl_net = net,
4225 };
4226
4227 cfg.fc_gateway = *gwaddr;
4228
4229 if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
4230 struct fib6_table *table;
4231
4232 table = fib6_get_table(dev_net(dev), cfg.fc_table);
4233 if (table)
4234 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
4235 }
4236
4237 return rt6_get_dflt_router(net, gwaddr, dev);
4238 }
4239
4240 static void __rt6_purge_dflt_routers(struct net *net,
4241 struct fib6_table *table)
4242 {
4243 struct fib6_info *rt;
4244
4245 restart:
4246 rcu_read_lock();
4247 for_each_fib6_node_rt_rcu(&table->tb6_root) {
4248 struct net_device *dev = fib6_info_nh_dev(rt);
4249 struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
4250
4251 if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
4252 (!idev || idev->cnf.accept_ra != 2) &&
4253 fib6_info_hold_safe(rt)) {
4254 rcu_read_unlock();
4255 ip6_del_rt(net, rt);
4256 goto restart;
4257 }
4258 }
4259 rcu_read_unlock();
4260
4261 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
4262 }
4263
4264 void rt6_purge_dflt_routers(struct net *net)
4265 {
4266 struct fib6_table *table;
4267 struct hlist_head *head;
4268 unsigned int h;
4269
4270 rcu_read_lock();
4271
4272 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
4273 head = &net->ipv6.fib_table_hash[h];
4274 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
4275 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
4276 __rt6_purge_dflt_routers(net, table);
4277 }
4278 }
4279
4280 rcu_read_unlock();
4281 }
4282
4283 static void rtmsg_to_fib6_config(struct net *net,
4284 struct in6_rtmsg *rtmsg,
4285 struct fib6_config *cfg)
4286 {
4287 *cfg = (struct fib6_config){
4288 .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
4289 : RT6_TABLE_MAIN,
4290 .fc_ifindex = rtmsg->rtmsg_ifindex,
4291 .fc_metric = rtmsg->rtmsg_metric ? : IP6_RT_PRIO_USER,
4292 .fc_expires = rtmsg->rtmsg_info,
4293 .fc_dst_len = rtmsg->rtmsg_dst_len,
4294 .fc_src_len = rtmsg->rtmsg_src_len,
4295 .fc_flags = rtmsg->rtmsg_flags,
4296 .fc_type = rtmsg->rtmsg_type,
4297
4298 .fc_nlinfo.nl_net = net,
4299
4300 .fc_dst = rtmsg->rtmsg_dst,
4301 .fc_src = rtmsg->rtmsg_src,
4302 .fc_gateway = rtmsg->rtmsg_gateway,
4303 };
4304 }
4305
4306 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
4307 {
4308 struct fib6_config cfg;
4309 struct in6_rtmsg rtmsg;
4310 int err;
4311
4312 switch (cmd) {
4313 case SIOCADDRT: /* Add a route */
4314 case SIOCDELRT: /* Delete a route */
4315 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
4316 return -EPERM;
4317 err = copy_from_user(&rtmsg, arg,
4318 sizeof(struct in6_rtmsg));
4319 if (err)
4320 return -EFAULT;
4321
4322 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
4323
4324 rtnl_lock();
4325 switch (cmd) {
4326 case SIOCADDRT:
4327 err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
4328 break;
4329 case SIOCDELRT:
4330 err = ip6_route_del(&cfg, NULL);
4331 break;
4332 default:
4333 err = -EINVAL;
4334 }
4335 rtnl_unlock();
4336
4337 return err;
4338 }
4339
4340 return -EINVAL;
4341 }
4342
4343 /*
4344 * Drop the packet on the floor
4345 */
4346
4347 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
4348 {
4349 struct dst_entry *dst = skb_dst(skb);
4350 struct net *net = dev_net(dst->dev);
4351 struct inet6_dev *idev;
4352 int type;
4353
4354 if (netif_is_l3_master(skb->dev) &&
4355 dst->dev == net->loopback_dev)
4356 idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif));
4357 else
4358 idev = ip6_dst_idev(dst);
4359
4360 switch (ipstats_mib_noroutes) {
4361 case IPSTATS_MIB_INNOROUTES:
4362 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
4363 if (type == IPV6_ADDR_ANY) {
4364 IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
4365 break;
4366 }
4367 fallthrough;
4368 case IPSTATS_MIB_OUTNOROUTES:
4369 IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
4370 break;
4371 }
4372
4373 /* Start over by dropping the dst for l3mdev case */
4374 if (netif_is_l3_master(skb->dev))
4375 skb_dst_drop(skb);
4376
4377 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
4378 kfree_skb(skb);
4379 return 0;
4380 }
4381
4382 static int ip6_pkt_discard(struct sk_buff *skb)
4383 {
4384 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
4385 }
4386
4387 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4388 {
4389 skb->dev = skb_dst(skb)->dev;
4390 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
4391 }
4392
4393 static int ip6_pkt_prohibit(struct sk_buff *skb)
4394 {
4395 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
4396 }
4397
4398 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
4399 {
4400 skb->dev = skb_dst(skb)->dev;
4401 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
4402 }
4403
4404 /*
4405 * Allocate a dst for local (unicast / anycast) address.
4406 */
4407
4408 struct fib6_info *addrconf_f6i_alloc(struct net *net,
4409 struct inet6_dev *idev,
4410 const struct in6_addr *addr,
4411 bool anycast, gfp_t gfp_flags)
4412 {
4413 struct fib6_config cfg = {
4414 .fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL,
4415 .fc_ifindex = idev->dev->ifindex,
4416 .fc_flags = RTF_UP | RTF_NONEXTHOP,
4417 .fc_dst = *addr,
4418 .fc_dst_len = 128,
4419 .fc_protocol = RTPROT_KERNEL,
4420 .fc_nlinfo.nl_net = net,
4421 .fc_ignore_dev_down = true,
4422 };
4423 struct fib6_info *f6i;
4424
4425 if (anycast) {
4426 cfg.fc_type = RTN_ANYCAST;
4427 cfg.fc_flags |= RTF_ANYCAST;
4428 } else {
4429 cfg.fc_type = RTN_LOCAL;
4430 cfg.fc_flags |= RTF_LOCAL;
4431 }
4432
4433 f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
4434 if (!IS_ERR(f6i))
4435 f6i->dst_nocount = true;
4436 return f6i;
4437 }
4438
4439 /* remove deleted ip from prefsrc entries */
4440 struct arg_dev_net_ip {
4441 struct net_device *dev;
4442 struct net *net;
4443 struct in6_addr *addr;
4444 };
4445
4446 static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg)
4447 {
4448 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
4449 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
4450 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
4451
4452 if (!rt->nh &&
4453 ((void *)rt->fib6_nh->fib_nh_dev == dev || !dev) &&
4454 rt != net->ipv6.fib6_null_entry &&
4455 ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr)) {
4456 spin_lock_bh(&rt6_exception_lock);
4457 /* remove prefsrc entry */
4458 rt->fib6_prefsrc.plen = 0;
4459 spin_unlock_bh(&rt6_exception_lock);
4460 }
4461 return 0;
4462 }
4463
4464 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
4465 {
4466 struct net *net = dev_net(ifp->idev->dev);
4467 struct arg_dev_net_ip adni = {
4468 .dev = ifp->idev->dev,
4469 .net = net,
4470 .addr = &ifp->addr,
4471 };
4472 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
4473 }
4474
4475 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT)
4476
4477 /* Remove routers and update dst entries when gateway turn into host. */
4478 static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
4479 {
4480 struct in6_addr *gateway = (struct in6_addr *)arg;
4481 struct fib6_nh *nh;
4482
4483 /* RA routes do not use nexthops */
4484 if (rt->nh)
4485 return 0;
4486
4487 nh = rt->fib6_nh;
4488 if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
4489 nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6))
4490 return -1;
4491
4492 /* Further clean up cached routes in exception table.
4493 * This is needed because cached route may have a different
4494 * gateway than its 'parent' in the case of an ip redirect.
4495 */
4496 fib6_nh_exceptions_clean_tohost(nh, gateway);
4497
4498 return 0;
4499 }
4500
4501 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
4502 {
4503 fib6_clean_all(net, fib6_clean_tohost, gateway);
4504 }
4505
4506 struct arg_netdev_event {
4507 const struct net_device *dev;
4508 union {
4509 unsigned char nh_flags;
4510 unsigned long event;
4511 };
4512 };
4513
4514 static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
4515 {
4516 struct fib6_info *iter;
4517 struct fib6_node *fn;
4518
4519 fn = rcu_dereference_protected(rt->fib6_node,
4520 lockdep_is_held(&rt->fib6_table->tb6_lock));
4521 iter = rcu_dereference_protected(fn->leaf,
4522 lockdep_is_held(&rt->fib6_table->tb6_lock));
4523 while (iter) {
4524 if (iter->fib6_metric == rt->fib6_metric &&
4525 rt6_qualify_for_ecmp(iter))
4526 return iter;
4527 iter = rcu_dereference_protected(iter->fib6_next,
4528 lockdep_is_held(&rt->fib6_table->tb6_lock));
4529 }
4530
4531 return NULL;
4532 }
4533
4534 /* only called for fib entries with builtin fib6_nh */
4535 static bool rt6_is_dead(const struct fib6_info *rt)
4536 {
4537 if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD ||
4538 (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN &&
4539 ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev)))
4540 return true;
4541
4542 return false;
4543 }
4544
4545 static int rt6_multipath_total_weight(const struct fib6_info *rt)
4546 {
4547 struct fib6_info *iter;
4548 int total = 0;
4549
4550 if (!rt6_is_dead(rt))
4551 total += rt->fib6_nh->fib_nh_weight;
4552
4553 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
4554 if (!rt6_is_dead(iter))
4555 total += iter->fib6_nh->fib_nh_weight;
4556 }
4557
4558 return total;
4559 }
4560
4561 static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
4562 {
4563 int upper_bound = -1;
4564
4565 if (!rt6_is_dead(rt)) {
4566 *weight += rt->fib6_nh->fib_nh_weight;
4567 upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
4568 total) - 1;
4569 }
4570 atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound);
4571 }
4572
4573 static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
4574 {
4575 struct fib6_info *iter;
4576 int weight = 0;
4577
4578 rt6_upper_bound_set(rt, &weight, total);
4579
4580 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4581 rt6_upper_bound_set(iter, &weight, total);
4582 }
4583
4584 void rt6_multipath_rebalance(struct fib6_info *rt)
4585 {
4586 struct fib6_info *first;
4587 int total;
4588
4589 /* In case the entire multipath route was marked for flushing,
4590 * then there is no need to rebalance upon the removal of every
4591 * sibling route.
4592 */
4593 if (!rt->fib6_nsiblings || rt->should_flush)
4594 return;
4595
4596 /* During lookup routes are evaluated in order, so we need to
4597 * make sure upper bounds are assigned from the first sibling
4598 * onwards.
4599 */
4600 first = rt6_multipath_first_sibling(rt);
4601 if (WARN_ON_ONCE(!first))
4602 return;
4603
4604 total = rt6_multipath_total_weight(first);
4605 rt6_multipath_upper_bound_set(first, total);
4606 }
4607
4608 static int fib6_ifup(struct fib6_info *rt, void *p_arg)
4609 {
4610 const struct arg_netdev_event *arg = p_arg;
4611 struct net *net = dev_net(arg->dev);
4612
4613 if (rt != net->ipv6.fib6_null_entry && !rt->nh &&
4614 rt->fib6_nh->fib_nh_dev == arg->dev) {
4615 rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags;
4616 fib6_update_sernum_upto_root(net, rt);
4617 rt6_multipath_rebalance(rt);
4618 }
4619
4620 return 0;
4621 }
4622
4623 void rt6_sync_up(struct net_device *dev, unsigned char nh_flags)
4624 {
4625 struct arg_netdev_event arg = {
4626 .dev = dev,
4627 {
4628 .nh_flags = nh_flags,
4629 },
4630 };
4631
4632 if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev))
4633 arg.nh_flags |= RTNH_F_LINKDOWN;
4634
4635 fib6_clean_all(dev_net(dev), fib6_ifup, &arg);
4636 }
4637
4638 /* only called for fib entries with inline fib6_nh */
4639 static bool rt6_multipath_uses_dev(const struct fib6_info *rt,
4640 const struct net_device *dev)
4641 {
4642 struct fib6_info *iter;
4643
4644 if (rt->fib6_nh->fib_nh_dev == dev)
4645 return true;
4646 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4647 if (iter->fib6_nh->fib_nh_dev == dev)
4648 return true;
4649
4650 return false;
4651 }
4652
4653 static void rt6_multipath_flush(struct fib6_info *rt)
4654 {
4655 struct fib6_info *iter;
4656
4657 rt->should_flush = 1;
4658 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4659 iter->should_flush = 1;
4660 }
4661
4662 static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt,
4663 const struct net_device *down_dev)
4664 {
4665 struct fib6_info *iter;
4666 unsigned int dead = 0;
4667
4668 if (rt->fib6_nh->fib_nh_dev == down_dev ||
4669 rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4670 dead++;
4671 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4672 if (iter->fib6_nh->fib_nh_dev == down_dev ||
4673 iter->fib6_nh->fib_nh_flags & RTNH_F_DEAD)
4674 dead++;
4675
4676 return dead;
4677 }
4678
4679 static void rt6_multipath_nh_flags_set(struct fib6_info *rt,
4680 const struct net_device *dev,
4681 unsigned char nh_flags)
4682 {
4683 struct fib6_info *iter;
4684
4685 if (rt->fib6_nh->fib_nh_dev == dev)
4686 rt->fib6_nh->fib_nh_flags |= nh_flags;
4687 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
4688 if (iter->fib6_nh->fib_nh_dev == dev)
4689 iter->fib6_nh->fib_nh_flags |= nh_flags;
4690 }
4691
4692 /* called with write lock held for table with rt */
4693 static int fib6_ifdown(struct fib6_info *rt, void *p_arg)
4694 {
4695 const struct arg_netdev_event *arg = p_arg;
4696 const struct net_device *dev = arg->dev;
4697 struct net *net = dev_net(dev);
4698
4699 if (rt == net->ipv6.fib6_null_entry || rt->nh)
4700 return 0;
4701
4702 switch (arg->event) {
4703 case NETDEV_UNREGISTER:
4704 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4705 case NETDEV_DOWN:
4706 if (rt->should_flush)
4707 return -1;
4708 if (!rt->fib6_nsiblings)
4709 return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
4710 if (rt6_multipath_uses_dev(rt, dev)) {
4711 unsigned int count;
4712
4713 count = rt6_multipath_dead_count(rt, dev);
4714 if (rt->fib6_nsiblings + 1 == count) {
4715 rt6_multipath_flush(rt);
4716 return -1;
4717 }
4718 rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
4719 RTNH_F_LINKDOWN);
4720 fib6_update_sernum(net, rt);
4721 rt6_multipath_rebalance(rt);
4722 }
4723 return -2;
4724 case NETDEV_CHANGE:
4725 if (rt->fib6_nh->fib_nh_dev != dev ||
4726 rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
4727 break;
4728 rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
4729 rt6_multipath_rebalance(rt);
4730 break;
4731 }
4732
4733 return 0;
4734 }
4735
4736 void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
4737 {
4738 struct arg_netdev_event arg = {
4739 .dev = dev,
4740 {
4741 .event = event,
4742 },
4743 };
4744 struct net *net = dev_net(dev);
4745
4746 if (net->ipv6.sysctl.skip_notify_on_dev_down)
4747 fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
4748 else
4749 fib6_clean_all(net, fib6_ifdown, &arg);
4750 }
4751
4752 void rt6_disable_ip(struct net_device *dev, unsigned long event)
4753 {
4754 rt6_sync_down_dev(dev, event);
4755 rt6_uncached_list_flush_dev(dev_net(dev), dev);
4756 neigh_ifdown(&nd_tbl, dev);
4757 }
4758
4759 struct rt6_mtu_change_arg {
4760 struct net_device *dev;
4761 unsigned int mtu;
4762 struct fib6_info *f6i;
4763 };
4764
4765 static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg)
4766 {
4767 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *)_arg;
4768 struct fib6_info *f6i = arg->f6i;
4769
4770 /* For administrative MTU increase, there is no way to discover
4771 * IPv6 PMTU increase, so PMTU increase should be updated here.
4772 * Since RFC 1981 doesn't include administrative MTU increase
4773 * update PMTU increase is a MUST. (i.e. jumbo frame)
4774 */
4775 if (nh->fib_nh_dev == arg->dev) {
4776 struct inet6_dev *idev = __in6_dev_get(arg->dev);
4777 u32 mtu = f6i->fib6_pmtu;
4778
4779 if (mtu >= arg->mtu ||
4780 (mtu < arg->mtu && mtu == idev->cnf.mtu6))
4781 fib6_metric_set(f6i, RTAX_MTU, arg->mtu);
4782
4783 spin_lock_bh(&rt6_exception_lock);
4784 rt6_exceptions_update_pmtu(idev, nh, arg->mtu);
4785 spin_unlock_bh(&rt6_exception_lock);
4786 }
4787
4788 return 0;
4789 }
4790
4791 static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
4792 {
4793 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
4794 struct inet6_dev *idev;
4795
4796 /* In IPv6 pmtu discovery is not optional,
4797 so that RTAX_MTU lock cannot disable it.
4798 We still use this lock to block changes
4799 caused by addrconf/ndisc.
4800 */
4801
4802 idev = __in6_dev_get(arg->dev);
4803 if (!idev)
4804 return 0;
4805
4806 if (fib6_metric_locked(f6i, RTAX_MTU))
4807 return 0;
4808
4809 arg->f6i = f6i;
4810 if (f6i->nh) {
4811 /* fib6_nh_mtu_change only returns 0, so this is safe */
4812 return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change,
4813 arg);
4814 }
4815
4816 return fib6_nh_mtu_change(f6i->fib6_nh, arg);
4817 }
4818
4819 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
4820 {
4821 struct rt6_mtu_change_arg arg = {
4822 .dev = dev,
4823 .mtu = mtu,
4824 };
4825
4826 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
4827 }
4828
4829 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
4830 [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 },
4831 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
4832 [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
4833 [RTA_OIF] = { .type = NLA_U32 },
4834 [RTA_IIF] = { .type = NLA_U32 },
4835 [RTA_PRIORITY] = { .type = NLA_U32 },
4836 [RTA_METRICS] = { .type = NLA_NESTED },
4837 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
4838 [RTA_PREF] = { .type = NLA_U8 },
4839 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
4840 [RTA_ENCAP] = { .type = NLA_NESTED },
4841 [RTA_EXPIRES] = { .type = NLA_U32 },
4842 [RTA_UID] = { .type = NLA_U32 },
4843 [RTA_MARK] = { .type = NLA_U32 },
4844 [RTA_TABLE] = { .type = NLA_U32 },
4845 [RTA_IP_PROTO] = { .type = NLA_U8 },
4846 [RTA_SPORT] = { .type = NLA_U16 },
4847 [RTA_DPORT] = { .type = NLA_U16 },
4848 [RTA_NH_ID] = { .type = NLA_U32 },
4849 };
4850
4851 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
4852 struct fib6_config *cfg,
4853 struct netlink_ext_ack *extack)
4854 {
4855 struct rtmsg *rtm;
4856 struct nlattr *tb[RTA_MAX+1];
4857 unsigned int pref;
4858 int err;
4859
4860 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
4861 rtm_ipv6_policy, extack);
4862 if (err < 0)
4863 goto errout;
4864
4865 err = -EINVAL;
4866 rtm = nlmsg_data(nlh);
4867
4868 *cfg = (struct fib6_config){
4869 .fc_table = rtm->rtm_table,
4870 .fc_dst_len = rtm->rtm_dst_len,
4871 .fc_src_len = rtm->rtm_src_len,
4872 .fc_flags = RTF_UP,
4873 .fc_protocol = rtm->rtm_protocol,
4874 .fc_type = rtm->rtm_type,
4875
4876 .fc_nlinfo.portid = NETLINK_CB(skb).portid,
4877 .fc_nlinfo.nlh = nlh,
4878 .fc_nlinfo.nl_net = sock_net(skb->sk),
4879 };
4880
4881 if (rtm->rtm_type == RTN_UNREACHABLE ||
4882 rtm->rtm_type == RTN_BLACKHOLE ||
4883 rtm->rtm_type == RTN_PROHIBIT ||
4884 rtm->rtm_type == RTN_THROW)
4885 cfg->fc_flags |= RTF_REJECT;
4886
4887 if (rtm->rtm_type == RTN_LOCAL)
4888 cfg->fc_flags |= RTF_LOCAL;
4889
4890 if (rtm->rtm_flags & RTM_F_CLONED)
4891 cfg->fc_flags |= RTF_CACHE;
4892
4893 cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
4894
4895 if (tb[RTA_NH_ID]) {
4896 if (tb[RTA_GATEWAY] || tb[RTA_OIF] ||
4897 tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) {
4898 NL_SET_ERR_MSG(extack,
4899 "Nexthop specification and nexthop id are mutually exclusive");
4900 goto errout;
4901 }
4902 cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]);
4903 }
4904
4905 if (tb[RTA_GATEWAY]) {
4906 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
4907 cfg->fc_flags |= RTF_GATEWAY;
4908 }
4909 if (tb[RTA_VIA]) {
4910 NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute");
4911 goto errout;
4912 }
4913
4914 if (tb[RTA_DST]) {
4915 int plen = (rtm->rtm_dst_len + 7) >> 3;
4916
4917 if (nla_len(tb[RTA_DST]) < plen)
4918 goto errout;
4919
4920 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
4921 }
4922
4923 if (tb[RTA_SRC]) {
4924 int plen = (rtm->rtm_src_len + 7) >> 3;
4925
4926 if (nla_len(tb[RTA_SRC]) < plen)
4927 goto errout;
4928
4929 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
4930 }
4931
4932 if (tb[RTA_PREFSRC])
4933 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
4934
4935 if (tb[RTA_OIF])
4936 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
4937
4938 if (tb[RTA_PRIORITY])
4939 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
4940
4941 if (tb[RTA_METRICS]) {
4942 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
4943 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
4944 }
4945
4946 if (tb[RTA_TABLE])
4947 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
4948
4949 if (tb[RTA_MULTIPATH]) {
4950 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
4951 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
4952
4953 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
4954 cfg->fc_mp_len, extack);
4955 if (err < 0)
4956 goto errout;
4957 }
4958
4959 if (tb[RTA_PREF]) {
4960 pref = nla_get_u8(tb[RTA_PREF]);
4961 if (pref != ICMPV6_ROUTER_PREF_LOW &&
4962 pref != ICMPV6_ROUTER_PREF_HIGH)
4963 pref = ICMPV6_ROUTER_PREF_MEDIUM;
4964 cfg->fc_flags |= RTF_PREF(pref);
4965 }
4966
4967 if (tb[RTA_ENCAP])
4968 cfg->fc_encap = tb[RTA_ENCAP];
4969
4970 if (tb[RTA_ENCAP_TYPE]) {
4971 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
4972
4973 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
4974 if (err < 0)
4975 goto errout;
4976 }
4977
4978 if (tb[RTA_EXPIRES]) {
4979 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
4980
4981 if (addrconf_finite_timeout(timeout)) {
4982 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
4983 cfg->fc_flags |= RTF_EXPIRES;
4984 }
4985 }
4986
4987 err = 0;
4988 errout:
4989 return err;
4990 }
4991
4992 struct rt6_nh {
4993 struct fib6_info *fib6_info;
4994 struct fib6_config r_cfg;
4995 struct list_head next;
4996 };
4997
4998 static int ip6_route_info_append(struct net *net,
4999 struct list_head *rt6_nh_list,
5000 struct fib6_info *rt,
5001 struct fib6_config *r_cfg)
5002 {
5003 struct rt6_nh *nh;
5004 int err = -EEXIST;
5005
5006 list_for_each_entry(nh, rt6_nh_list, next) {
5007 /* check if fib6_info already exists */
5008 if (rt6_duplicate_nexthop(nh->fib6_info, rt))
5009 return err;
5010 }
5011
5012 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
5013 if (!nh)
5014 return -ENOMEM;
5015 nh->fib6_info = rt;
5016 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
5017 list_add_tail(&nh->next, rt6_nh_list);
5018
5019 return 0;
5020 }
5021
5022 static void ip6_route_mpath_notify(struct fib6_info *rt,
5023 struct fib6_info *rt_last,
5024 struct nl_info *info,
5025 __u16 nlflags)
5026 {
5027 /* if this is an APPEND route, then rt points to the first route
5028 * inserted and rt_last points to last route inserted. Userspace
5029 * wants a consistent dump of the route which starts at the first
5030 * nexthop. Since sibling routes are always added at the end of
5031 * the list, find the first sibling of the last route appended
5032 */
5033 if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
5034 rt = list_first_entry(&rt_last->fib6_siblings,
5035 struct fib6_info,
5036 fib6_siblings);
5037 }
5038
5039 if (rt)
5040 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
5041 }
5042
5043 static bool ip6_route_mpath_should_notify(const struct fib6_info *rt)
5044 {
5045 bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
5046 bool should_notify = false;
5047 struct fib6_info *leaf;
5048 struct fib6_node *fn;
5049
5050 rcu_read_lock();
5051 fn = rcu_dereference(rt->fib6_node);
5052 if (!fn)
5053 goto out;
5054
5055 leaf = rcu_dereference(fn->leaf);
5056 if (!leaf)
5057 goto out;
5058
5059 if (rt == leaf ||
5060 (rt_can_ecmp && rt->fib6_metric == leaf->fib6_metric &&
5061 rt6_qualify_for_ecmp(leaf)))
5062 should_notify = true;
5063 out:
5064 rcu_read_unlock();
5065
5066 return should_notify;
5067 }
5068
5069 static int ip6_route_multipath_add(struct fib6_config *cfg,
5070 struct netlink_ext_ack *extack)
5071 {
5072 struct fib6_info *rt_notif = NULL, *rt_last = NULL;
5073 struct nl_info *info = &cfg->fc_nlinfo;
5074 struct fib6_config r_cfg;
5075 struct rtnexthop *rtnh;
5076 struct fib6_info *rt;
5077 struct rt6_nh *err_nh;
5078 struct rt6_nh *nh, *nh_safe;
5079 __u16 nlflags;
5080 int remaining;
5081 int attrlen;
5082 int err = 1;
5083 int nhn = 0;
5084 int replace = (cfg->fc_nlinfo.nlh &&
5085 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
5086 LIST_HEAD(rt6_nh_list);
5087
5088 nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
5089 if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
5090 nlflags |= NLM_F_APPEND;
5091
5092 remaining = cfg->fc_mp_len;
5093 rtnh = (struct rtnexthop *)cfg->fc_mp;
5094
5095 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
5096 * fib6_info structs per nexthop
5097 */
5098 while (rtnh_ok(rtnh, remaining)) {
5099 memcpy(&r_cfg, cfg, sizeof(*cfg));
5100 if (rtnh->rtnh_ifindex)
5101 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5102
5103 attrlen = rtnh_attrlen(rtnh);
5104 if (attrlen > 0) {
5105 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5106
5107 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5108 if (nla) {
5109 r_cfg.fc_gateway = nla_get_in6_addr(nla);
5110 r_cfg.fc_flags |= RTF_GATEWAY;
5111 }
5112 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
5113 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
5114 if (nla)
5115 r_cfg.fc_encap_type = nla_get_u16(nla);
5116 }
5117
5118 r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
5119 rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
5120 if (IS_ERR(rt)) {
5121 err = PTR_ERR(rt);
5122 rt = NULL;
5123 goto cleanup;
5124 }
5125 if (!rt6_qualify_for_ecmp(rt)) {
5126 err = -EINVAL;
5127 NL_SET_ERR_MSG(extack,
5128 "Device only routes can not be added for IPv6 using the multipath API.");
5129 fib6_info_release(rt);
5130 goto cleanup;
5131 }
5132
5133 rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1;
5134
5135 err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
5136 rt, &r_cfg);
5137 if (err) {
5138 fib6_info_release(rt);
5139 goto cleanup;
5140 }
5141
5142 rtnh = rtnh_next(rtnh, &remaining);
5143 }
5144
5145 if (list_empty(&rt6_nh_list)) {
5146 NL_SET_ERR_MSG(extack,
5147 "Invalid nexthop configuration - no valid nexthops");
5148 return -EINVAL;
5149 }
5150
5151 /* for add and replace send one notification with all nexthops.
5152 * Skip the notification in fib6_add_rt2node and send one with
5153 * the full route when done
5154 */
5155 info->skip_notify = 1;
5156
5157 /* For add and replace, send one notification with all nexthops. For
5158 * append, send one notification with all appended nexthops.
5159 */
5160 info->skip_notify_kernel = 1;
5161
5162 err_nh = NULL;
5163 list_for_each_entry(nh, &rt6_nh_list, next) {
5164 err = __ip6_ins_rt(nh->fib6_info, info, extack);
5165 fib6_info_release(nh->fib6_info);
5166
5167 if (!err) {
5168 /* save reference to last route successfully inserted */
5169 rt_last = nh->fib6_info;
5170
5171 /* save reference to first route for notification */
5172 if (!rt_notif)
5173 rt_notif = nh->fib6_info;
5174 }
5175
5176 /* nh->fib6_info is used or freed at this point, reset to NULL*/
5177 nh->fib6_info = NULL;
5178 if (err) {
5179 if (replace && nhn)
5180 NL_SET_ERR_MSG_MOD(extack,
5181 "multipath route replace failed (check consistency of installed routes)");
5182 err_nh = nh;
5183 goto add_errout;
5184 }
5185
5186 /* Because each route is added like a single route we remove
5187 * these flags after the first nexthop: if there is a collision,
5188 * we have already failed to add the first nexthop:
5189 * fib6_add_rt2node() has rejected it; when replacing, old
5190 * nexthops have been replaced by first new, the rest should
5191 * be added to it.
5192 */
5193 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
5194 NLM_F_REPLACE);
5195 cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
5196 nhn++;
5197 }
5198
5199 /* An in-kernel notification should only be sent in case the new
5200 * multipath route is added as the first route in the node, or if
5201 * it was appended to it. We pass 'rt_notif' since it is the first
5202 * sibling and might allow us to skip some checks in the replace case.
5203 */
5204 if (ip6_route_mpath_should_notify(rt_notif)) {
5205 enum fib_event_type fib_event;
5206
5207 if (rt_notif->fib6_nsiblings != nhn - 1)
5208 fib_event = FIB_EVENT_ENTRY_APPEND;
5209 else
5210 fib_event = FIB_EVENT_ENTRY_REPLACE;
5211
5212 err = call_fib6_multipath_entry_notifiers(info->nl_net,
5213 fib_event, rt_notif,
5214 nhn - 1, extack);
5215 if (err) {
5216 /* Delete all the siblings that were just added */
5217 err_nh = NULL;
5218 goto add_errout;
5219 }
5220 }
5221
5222 /* success ... tell user about new route */
5223 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5224 goto cleanup;
5225
5226 add_errout:
5227 /* send notification for routes that were added so that
5228 * the delete notifications sent by ip6_route_del are
5229 * coherent
5230 */
5231 if (rt_notif)
5232 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
5233
5234 /* Delete routes that were already added */
5235 list_for_each_entry(nh, &rt6_nh_list, next) {
5236 if (err_nh == nh)
5237 break;
5238 ip6_route_del(&nh->r_cfg, extack);
5239 }
5240
5241 cleanup:
5242 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
5243 if (nh->fib6_info)
5244 fib6_info_release(nh->fib6_info);
5245 list_del(&nh->next);
5246 kfree(nh);
5247 }
5248
5249 return err;
5250 }
5251
5252 static int ip6_route_multipath_del(struct fib6_config *cfg,
5253 struct netlink_ext_ack *extack)
5254 {
5255 struct fib6_config r_cfg;
5256 struct rtnexthop *rtnh;
5257 int remaining;
5258 int attrlen;
5259 int err = 1, last_err = 0;
5260
5261 remaining = cfg->fc_mp_len;
5262 rtnh = (struct rtnexthop *)cfg->fc_mp;
5263
5264 /* Parse a Multipath Entry */
5265 while (rtnh_ok(rtnh, remaining)) {
5266 memcpy(&r_cfg, cfg, sizeof(*cfg));
5267 if (rtnh->rtnh_ifindex)
5268 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
5269
5270 attrlen = rtnh_attrlen(rtnh);
5271 if (attrlen > 0) {
5272 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
5273
5274 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
5275 if (nla) {
5276 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
5277 r_cfg.fc_flags |= RTF_GATEWAY;
5278 }
5279 }
5280 err = ip6_route_del(&r_cfg, extack);
5281 if (err)
5282 last_err = err;
5283
5284 rtnh = rtnh_next(rtnh, &remaining);
5285 }
5286
5287 return last_err;
5288 }
5289
5290 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5291 struct netlink_ext_ack *extack)
5292 {
5293 struct fib6_config cfg;
5294 int err;
5295
5296 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5297 if (err < 0)
5298 return err;
5299
5300 if (cfg.fc_nh_id &&
5301 !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id)) {
5302 NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
5303 return -EINVAL;
5304 }
5305
5306 if (cfg.fc_mp)
5307 return ip6_route_multipath_del(&cfg, extack);
5308 else {
5309 cfg.fc_delete_all_nh = 1;
5310 return ip6_route_del(&cfg, extack);
5311 }
5312 }
5313
5314 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
5315 struct netlink_ext_ack *extack)
5316 {
5317 struct fib6_config cfg;
5318 int err;
5319
5320 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
5321 if (err < 0)
5322 return err;
5323
5324 if (cfg.fc_metric == 0)
5325 cfg.fc_metric = IP6_RT_PRIO_USER;
5326
5327 if (cfg.fc_mp)
5328 return ip6_route_multipath_add(&cfg, extack);
5329 else
5330 return ip6_route_add(&cfg, GFP_KERNEL, extack);
5331 }
5332
5333 /* add the overhead of this fib6_nh to nexthop_len */
5334 static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
5335 {
5336 int *nexthop_len = arg;
5337
5338 *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */
5339 + NLA_ALIGN(sizeof(struct rtnexthop))
5340 + nla_total_size(16); /* RTA_GATEWAY */
5341
5342 if (nh->fib_nh_lws) {
5343 /* RTA_ENCAP_TYPE */
5344 *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5345 /* RTA_ENCAP */
5346 *nexthop_len += nla_total_size(2);
5347 }
5348
5349 return 0;
5350 }
5351
5352 static size_t rt6_nlmsg_size(struct fib6_info *f6i)
5353 {
5354 int nexthop_len;
5355
5356 if (f6i->nh) {
5357 nexthop_len = nla_total_size(4); /* RTA_NH_ID */
5358 nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size,
5359 &nexthop_len);
5360 } else {
5361 struct fib6_nh *nh = f6i->fib6_nh;
5362
5363 nexthop_len = 0;
5364 if (f6i->fib6_nsiblings) {
5365 nexthop_len = nla_total_size(0) /* RTA_MULTIPATH */
5366 + NLA_ALIGN(sizeof(struct rtnexthop))
5367 + nla_total_size(16) /* RTA_GATEWAY */
5368 + lwtunnel_get_encap_size(nh->fib_nh_lws);
5369
5370 nexthop_len *= f6i->fib6_nsiblings;
5371 }
5372 nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
5373 }
5374
5375 return NLMSG_ALIGN(sizeof(struct rtmsg))
5376 + nla_total_size(16) /* RTA_SRC */
5377 + nla_total_size(16) /* RTA_DST */
5378 + nla_total_size(16) /* RTA_GATEWAY */
5379 + nla_total_size(16) /* RTA_PREFSRC */
5380 + nla_total_size(4) /* RTA_TABLE */
5381 + nla_total_size(4) /* RTA_IIF */
5382 + nla_total_size(4) /* RTA_OIF */
5383 + nla_total_size(4) /* RTA_PRIORITY */
5384 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
5385 + nla_total_size(sizeof(struct rta_cacheinfo))
5386 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
5387 + nla_total_size(1) /* RTA_PREF */
5388 + nexthop_len;
5389 }
5390
5391 static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh,
5392 unsigned char *flags)
5393 {
5394 if (nexthop_is_multipath(nh)) {
5395 struct nlattr *mp;
5396
5397 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5398 if (!mp)
5399 goto nla_put_failure;
5400
5401 if (nexthop_mpath_fill_node(skb, nh, AF_INET6))
5402 goto nla_put_failure;
5403
5404 nla_nest_end(skb, mp);
5405 } else {
5406 struct fib6_nh *fib6_nh;
5407
5408 fib6_nh = nexthop_fib6_nh(nh);
5409 if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6,
5410 flags, false) < 0)
5411 goto nla_put_failure;
5412 }
5413
5414 return 0;
5415
5416 nla_put_failure:
5417 return -EMSGSIZE;
5418 }
5419
5420 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
5421 struct fib6_info *rt, struct dst_entry *dst,
5422 struct in6_addr *dest, struct in6_addr *src,
5423 int iif, int type, u32 portid, u32 seq,
5424 unsigned int flags)
5425 {
5426 struct rt6_info *rt6 = (struct rt6_info *)dst;
5427 struct rt6key *rt6_dst, *rt6_src;
5428 u32 *pmetrics, table, rt6_flags;
5429 unsigned char nh_flags = 0;
5430 struct nlmsghdr *nlh;
5431 struct rtmsg *rtm;
5432 long expires = 0;
5433
5434 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
5435 if (!nlh)
5436 return -EMSGSIZE;
5437
5438 if (rt6) {
5439 rt6_dst = &rt6->rt6i_dst;
5440 rt6_src = &rt6->rt6i_src;
5441 rt6_flags = rt6->rt6i_flags;
5442 } else {
5443 rt6_dst = &rt->fib6_dst;
5444 rt6_src = &rt->fib6_src;
5445 rt6_flags = rt->fib6_flags;
5446 }
5447
5448 rtm = nlmsg_data(nlh);
5449 rtm->rtm_family = AF_INET6;
5450 rtm->rtm_dst_len = rt6_dst->plen;
5451 rtm->rtm_src_len = rt6_src->plen;
5452 rtm->rtm_tos = 0;
5453 if (rt->fib6_table)
5454 table = rt->fib6_table->tb6_id;
5455 else
5456 table = RT6_TABLE_UNSPEC;
5457 rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
5458 if (nla_put_u32(skb, RTA_TABLE, table))
5459 goto nla_put_failure;
5460
5461 rtm->rtm_type = rt->fib6_type;
5462 rtm->rtm_flags = 0;
5463 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
5464 rtm->rtm_protocol = rt->fib6_protocol;
5465
5466 if (rt6_flags & RTF_CACHE)
5467 rtm->rtm_flags |= RTM_F_CLONED;
5468
5469 if (dest) {
5470 if (nla_put_in6_addr(skb, RTA_DST, dest))
5471 goto nla_put_failure;
5472 rtm->rtm_dst_len = 128;
5473 } else if (rtm->rtm_dst_len)
5474 if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr))
5475 goto nla_put_failure;
5476 #ifdef CONFIG_IPV6_SUBTREES
5477 if (src) {
5478 if (nla_put_in6_addr(skb, RTA_SRC, src))
5479 goto nla_put_failure;
5480 rtm->rtm_src_len = 128;
5481 } else if (rtm->rtm_src_len &&
5482 nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
5483 goto nla_put_failure;
5484 #endif
5485 if (iif) {
5486 #ifdef CONFIG_IPV6_MROUTE
5487 if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
5488 int err = ip6mr_get_route(net, skb, rtm, portid);
5489
5490 if (err == 0)
5491 return 0;
5492 if (err < 0)
5493 goto nla_put_failure;
5494 } else
5495 #endif
5496 if (nla_put_u32(skb, RTA_IIF, iif))
5497 goto nla_put_failure;
5498 } else if (dest) {
5499 struct in6_addr saddr_buf;
5500 if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 &&
5501 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5502 goto nla_put_failure;
5503 }
5504
5505 if (rt->fib6_prefsrc.plen) {
5506 struct in6_addr saddr_buf;
5507 saddr_buf = rt->fib6_prefsrc.addr;
5508 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
5509 goto nla_put_failure;
5510 }
5511
5512 pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics;
5513 if (rtnetlink_put_metrics(skb, pmetrics) < 0)
5514 goto nla_put_failure;
5515
5516 if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric))
5517 goto nla_put_failure;
5518
5519 /* For multipath routes, walk the siblings list and add
5520 * each as a nexthop within RTA_MULTIPATH.
5521 */
5522 if (rt6) {
5523 if (rt6_flags & RTF_GATEWAY &&
5524 nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
5525 goto nla_put_failure;
5526
5527 if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
5528 goto nla_put_failure;
5529 } else if (rt->fib6_nsiblings) {
5530 struct fib6_info *sibling, *next_sibling;
5531 struct nlattr *mp;
5532
5533 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
5534 if (!mp)
5535 goto nla_put_failure;
5536
5537 if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common,
5538 rt->fib6_nh->fib_nh_weight, AF_INET6) < 0)
5539 goto nla_put_failure;
5540
5541 list_for_each_entry_safe(sibling, next_sibling,
5542 &rt->fib6_siblings, fib6_siblings) {
5543 if (fib_add_nexthop(skb, &sibling->fib6_nh->nh_common,
5544 sibling->fib6_nh->fib_nh_weight,
5545 AF_INET6) < 0)
5546 goto nla_put_failure;
5547 }
5548
5549 nla_nest_end(skb, mp);
5550 } else if (rt->nh) {
5551 if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id))
5552 goto nla_put_failure;
5553
5554 if (nexthop_is_blackhole(rt->nh))
5555 rtm->rtm_type = RTN_BLACKHOLE;
5556
5557 if (rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0)
5558 goto nla_put_failure;
5559
5560 rtm->rtm_flags |= nh_flags;
5561 } else {
5562 if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6,
5563 &nh_flags, false) < 0)
5564 goto nla_put_failure;
5565
5566 rtm->rtm_flags |= nh_flags;
5567 }
5568
5569 if (rt6_flags & RTF_EXPIRES) {
5570 expires = dst ? dst->expires : rt->expires;
5571 expires -= jiffies;
5572 }
5573
5574 if (!dst) {
5575 if (rt->offload)
5576 rtm->rtm_flags |= RTM_F_OFFLOAD;
5577 if (rt->trap)
5578 rtm->rtm_flags |= RTM_F_TRAP;
5579 }
5580
5581 if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
5582 goto nla_put_failure;
5583
5584 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
5585 goto nla_put_failure;
5586
5587
5588 nlmsg_end(skb, nlh);
5589 return 0;
5590
5591 nla_put_failure:
5592 nlmsg_cancel(skb, nlh);
5593 return -EMSGSIZE;
5594 }
5595
5596 static int fib6_info_nh_uses_dev(struct fib6_nh *nh, void *arg)
5597 {
5598 const struct net_device *dev = arg;
5599
5600 if (nh->fib_nh_dev == dev)
5601 return 1;
5602
5603 return 0;
5604 }
5605
5606 static bool fib6_info_uses_dev(const struct fib6_info *f6i,
5607 const struct net_device *dev)
5608 {
5609 if (f6i->nh) {
5610 struct net_device *_dev = (struct net_device *)dev;
5611
5612 return !!nexthop_for_each_fib6_nh(f6i->nh,
5613 fib6_info_nh_uses_dev,
5614 _dev);
5615 }
5616
5617 if (f6i->fib6_nh->fib_nh_dev == dev)
5618 return true;
5619
5620 if (f6i->fib6_nsiblings) {
5621 struct fib6_info *sibling, *next_sibling;
5622
5623 list_for_each_entry_safe(sibling, next_sibling,
5624 &f6i->fib6_siblings, fib6_siblings) {
5625 if (sibling->fib6_nh->fib_nh_dev == dev)
5626 return true;
5627 }
5628 }
5629
5630 return false;
5631 }
5632
5633 struct fib6_nh_exception_dump_walker {
5634 struct rt6_rtnl_dump_arg *dump;
5635 struct fib6_info *rt;
5636 unsigned int flags;
5637 unsigned int skip;
5638 unsigned int count;
5639 };
5640
5641 static int rt6_nh_dump_exceptions(struct fib6_nh *nh, void *arg)
5642 {
5643 struct fib6_nh_exception_dump_walker *w = arg;
5644 struct rt6_rtnl_dump_arg *dump = w->dump;
5645 struct rt6_exception_bucket *bucket;
5646 struct rt6_exception *rt6_ex;
5647 int i, err;
5648
5649 bucket = fib6_nh_get_excptn_bucket(nh, NULL);
5650 if (!bucket)
5651 return 0;
5652
5653 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
5654 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
5655 if (w->skip) {
5656 w->skip--;
5657 continue;
5658 }
5659
5660 /* Expiration of entries doesn't bump sernum, insertion
5661 * does. Removal is triggered by insertion, so we can
5662 * rely on the fact that if entries change between two
5663 * partial dumps, this node is scanned again completely,
5664 * see rt6_insert_exception() and fib6_dump_table().
5665 *
5666 * Count expired entries we go through as handled
5667 * entries that we'll skip next time, in case of partial
5668 * node dump. Otherwise, if entries expire meanwhile,
5669 * we'll skip the wrong amount.
5670 */
5671 if (rt6_check_expired(rt6_ex->rt6i)) {
5672 w->count++;
5673 continue;
5674 }
5675
5676 err = rt6_fill_node(dump->net, dump->skb, w->rt,
5677 &rt6_ex->rt6i->dst, NULL, NULL, 0,
5678 RTM_NEWROUTE,
5679 NETLINK_CB(dump->cb->skb).portid,
5680 dump->cb->nlh->nlmsg_seq, w->flags);
5681 if (err)
5682 return err;
5683
5684 w->count++;
5685 }
5686 bucket++;
5687 }
5688
5689 return 0;
5690 }
5691
5692 /* Return -1 if done with node, number of handled routes on partial dump */
5693 int rt6_dump_route(struct fib6_info *rt, void *p_arg, unsigned int skip)
5694 {
5695 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
5696 struct fib_dump_filter *filter = &arg->filter;
5697 unsigned int flags = NLM_F_MULTI;
5698 struct net *net = arg->net;
5699 int count = 0;
5700
5701 if (rt == net->ipv6.fib6_null_entry)
5702 return -1;
5703
5704 if ((filter->flags & RTM_F_PREFIX) &&
5705 !(rt->fib6_flags & RTF_PREFIX_RT)) {
5706 /* success since this is not a prefix route */
5707 return -1;
5708 }
5709 if (filter->filter_set &&
5710 ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
5711 (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
5712 (filter->protocol && rt->fib6_protocol != filter->protocol))) {
5713 return -1;
5714 }
5715
5716 if (filter->filter_set ||
5717 !filter->dump_routes || !filter->dump_exceptions) {
5718 flags |= NLM_F_DUMP_FILTERED;
5719 }
5720
5721 if (filter->dump_routes) {
5722 if (skip) {
5723 skip--;
5724 } else {
5725 if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL,
5726 0, RTM_NEWROUTE,
5727 NETLINK_CB(arg->cb->skb).portid,
5728 arg->cb->nlh->nlmsg_seq, flags)) {
5729 return 0;
5730 }
5731 count++;
5732 }
5733 }
5734
5735 if (filter->dump_exceptions) {
5736 struct fib6_nh_exception_dump_walker w = { .dump = arg,
5737 .rt = rt,
5738 .flags = flags,
5739 .skip = skip,
5740 .count = 0 };
5741 int err;
5742
5743 rcu_read_lock();
5744 if (rt->nh) {
5745 err = nexthop_for_each_fib6_nh(rt->nh,
5746 rt6_nh_dump_exceptions,
5747 &w);
5748 } else {
5749 err = rt6_nh_dump_exceptions(rt->fib6_nh, &w);
5750 }
5751 rcu_read_unlock();
5752
5753 if (err)
5754 return count += w.count;
5755 }
5756
5757 return -1;
5758 }
5759
5760 static int inet6_rtm_valid_getroute_req(struct sk_buff *skb,
5761 const struct nlmsghdr *nlh,
5762 struct nlattr **tb,
5763 struct netlink_ext_ack *extack)
5764 {
5765 struct rtmsg *rtm;
5766 int i, err;
5767
5768 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
5769 NL_SET_ERR_MSG_MOD(extack,
5770 "Invalid header for get route request");
5771 return -EINVAL;
5772 }
5773
5774 if (!netlink_strict_get_check(skb))
5775 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
5776 rtm_ipv6_policy, extack);
5777
5778 rtm = nlmsg_data(nlh);
5779 if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
5780 (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
5781 rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope ||
5782 rtm->rtm_type) {
5783 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
5784 return -EINVAL;
5785 }
5786 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
5787 NL_SET_ERR_MSG_MOD(extack,
5788 "Invalid flags for get route request");
5789 return -EINVAL;
5790 }
5791
5792 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
5793 rtm_ipv6_policy, extack);
5794 if (err)
5795 return err;
5796
5797 if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
5798 (tb[RTA_DST] && !rtm->rtm_dst_len)) {
5799 NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6");
5800 return -EINVAL;
5801 }
5802
5803 for (i = 0; i <= RTA_MAX; i++) {
5804 if (!tb[i])
5805 continue;
5806
5807 switch (i) {
5808 case RTA_SRC:
5809 case RTA_DST:
5810 case RTA_IIF:
5811 case RTA_OIF:
5812 case RTA_MARK:
5813 case RTA_UID:
5814 case RTA_SPORT:
5815 case RTA_DPORT:
5816 case RTA_IP_PROTO:
5817 break;
5818 default:
5819 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
5820 return -EINVAL;
5821 }
5822 }
5823
5824 return 0;
5825 }
5826
5827 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5828 struct netlink_ext_ack *extack)
5829 {
5830 struct net *net = sock_net(in_skb->sk);
5831 struct nlattr *tb[RTA_MAX+1];
5832 int err, iif = 0, oif = 0;
5833 struct fib6_info *from;
5834 struct dst_entry *dst;
5835 struct rt6_info *rt;
5836 struct sk_buff *skb;
5837 struct rtmsg *rtm;
5838 struct flowi6 fl6 = {};
5839 bool fibmatch;
5840
5841 err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
5842 if (err < 0)
5843 goto errout;
5844
5845 err = -EINVAL;
5846 rtm = nlmsg_data(nlh);
5847 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
5848 fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH);
5849
5850 if (tb[RTA_SRC]) {
5851 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
5852 goto errout;
5853
5854 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
5855 }
5856
5857 if (tb[RTA_DST]) {
5858 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
5859 goto errout;
5860
5861 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
5862 }
5863
5864 if (tb[RTA_IIF])
5865 iif = nla_get_u32(tb[RTA_IIF]);
5866
5867 if (tb[RTA_OIF])
5868 oif = nla_get_u32(tb[RTA_OIF]);
5869
5870 if (tb[RTA_MARK])
5871 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
5872
5873 if (tb[RTA_UID])
5874 fl6.flowi6_uid = make_kuid(current_user_ns(),
5875 nla_get_u32(tb[RTA_UID]));
5876 else
5877 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
5878
5879 if (tb[RTA_SPORT])
5880 fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
5881
5882 if (tb[RTA_DPORT])
5883 fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
5884
5885 if (tb[RTA_IP_PROTO]) {
5886 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
5887 &fl6.flowi6_proto, AF_INET6,
5888 extack);
5889 if (err)
5890 goto errout;
5891 }
5892
5893 if (iif) {
5894 struct net_device *dev;
5895 int flags = 0;
5896
5897 rcu_read_lock();
5898
5899 dev = dev_get_by_index_rcu(net, iif);
5900 if (!dev) {
5901 rcu_read_unlock();
5902 err = -ENODEV;
5903 goto errout;
5904 }
5905
5906 fl6.flowi6_iif = iif;
5907
5908 if (!ipv6_addr_any(&fl6.saddr))
5909 flags |= RT6_LOOKUP_F_HAS_SADDR;
5910
5911 dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
5912
5913 rcu_read_unlock();
5914 } else {
5915 fl6.flowi6_oif = oif;
5916
5917 dst = ip6_route_output(net, NULL, &fl6);
5918 }
5919
5920
5921 rt = container_of(dst, struct rt6_info, dst);
5922 if (rt->dst.error) {
5923 err = rt->dst.error;
5924 ip6_rt_put(rt);
5925 goto errout;
5926 }
5927
5928 if (rt == net->ipv6.ip6_null_entry) {
5929 err = rt->dst.error;
5930 ip6_rt_put(rt);
5931 goto errout;
5932 }
5933
5934 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
5935 if (!skb) {
5936 ip6_rt_put(rt);
5937 err = -ENOBUFS;
5938 goto errout;
5939 }
5940
5941 skb_dst_set(skb, &rt->dst);
5942
5943 rcu_read_lock();
5944 from = rcu_dereference(rt->from);
5945 if (from) {
5946 if (fibmatch)
5947 err = rt6_fill_node(net, skb, from, NULL, NULL, NULL,
5948 iif, RTM_NEWROUTE,
5949 NETLINK_CB(in_skb).portid,
5950 nlh->nlmsg_seq, 0);
5951 else
5952 err = rt6_fill_node(net, skb, from, dst, &fl6.daddr,
5953 &fl6.saddr, iif, RTM_NEWROUTE,
5954 NETLINK_CB(in_skb).portid,
5955 nlh->nlmsg_seq, 0);
5956 } else {
5957 err = -ENETUNREACH;
5958 }
5959 rcu_read_unlock();
5960
5961 if (err < 0) {
5962 kfree_skb(skb);
5963 goto errout;
5964 }
5965
5966 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5967 errout:
5968 return err;
5969 }
5970
5971 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
5972 unsigned int nlm_flags)
5973 {
5974 struct sk_buff *skb;
5975 struct net *net = info->nl_net;
5976 u32 seq;
5977 int err;
5978
5979 err = -ENOBUFS;
5980 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
5981
5982 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
5983 if (!skb)
5984 goto errout;
5985
5986 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
5987 event, info->portid, seq, nlm_flags);
5988 if (err < 0) {
5989 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
5990 WARN_ON(err == -EMSGSIZE);
5991 kfree_skb(skb);
5992 goto errout;
5993 }
5994 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
5995 info->nlh, gfp_any());
5996 return;
5997 errout:
5998 if (err < 0)
5999 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6000 }
6001
6002 void fib6_rt_update(struct net *net, struct fib6_info *rt,
6003 struct nl_info *info)
6004 {
6005 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
6006 struct sk_buff *skb;
6007 int err = -ENOBUFS;
6008
6009 /* call_fib6_entry_notifiers will be removed when in-kernel notifier
6010 * is implemented and supported for nexthop objects
6011 */
6012 call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, rt, NULL);
6013
6014 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
6015 if (!skb)
6016 goto errout;
6017
6018 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
6019 RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
6020 if (err < 0) {
6021 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
6022 WARN_ON(err == -EMSGSIZE);
6023 kfree_skb(skb);
6024 goto errout;
6025 }
6026 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
6027 info->nlh, gfp_any());
6028 return;
6029 errout:
6030 if (err < 0)
6031 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
6032 }
6033
6034 static int ip6_route_dev_notify(struct notifier_block *this,
6035 unsigned long event, void *ptr)
6036 {
6037 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
6038 struct net *net = dev_net(dev);
6039
6040 if (!(dev->flags & IFF_LOOPBACK))
6041 return NOTIFY_OK;
6042
6043 if (event == NETDEV_REGISTER) {
6044 net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev;
6045 net->ipv6.ip6_null_entry->dst.dev = dev;
6046 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
6047 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6048 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
6049 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
6050 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
6051 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
6052 #endif
6053 } else if (event == NETDEV_UNREGISTER &&
6054 dev->reg_state != NETREG_UNREGISTERED) {
6055 /* NETDEV_UNREGISTER could be fired for multiple times by
6056 * netdev_wait_allrefs(). Make sure we only call this once.
6057 */
6058 in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
6059 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6060 in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
6061 in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
6062 #endif
6063 }
6064
6065 return NOTIFY_OK;
6066 }
6067
6068 /*
6069 * /proc
6070 */
6071
6072 #ifdef CONFIG_PROC_FS
6073 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
6074 {
6075 struct net *net = (struct net *)seq->private;
6076 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
6077 net->ipv6.rt6_stats->fib_nodes,
6078 net->ipv6.rt6_stats->fib_route_nodes,
6079 atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
6080 net->ipv6.rt6_stats->fib_rt_entries,
6081 net->ipv6.rt6_stats->fib_rt_cache,
6082 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
6083 net->ipv6.rt6_stats->fib_discarded_routes);
6084
6085 return 0;
6086 }
6087 #endif /* CONFIG_PROC_FS */
6088
6089 #ifdef CONFIG_SYSCTL
6090
6091 static
6092 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
6093 void __user *buffer, size_t *lenp, loff_t *ppos)
6094 {
6095 struct net *net;
6096 int delay;
6097 int ret;
6098 if (!write)
6099 return -EINVAL;
6100
6101 net = (struct net *)ctl->extra1;
6102 delay = net->ipv6.sysctl.flush_delay;
6103 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6104 if (ret)
6105 return ret;
6106
6107 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
6108 return 0;
6109 }
6110
6111 static struct ctl_table ipv6_route_table_template[] = {
6112 {
6113 .procname = "flush",
6114 .data = &init_net.ipv6.sysctl.flush_delay,
6115 .maxlen = sizeof(int),
6116 .mode = 0200,
6117 .proc_handler = ipv6_sysctl_rtcache_flush
6118 },
6119 {
6120 .procname = "gc_thresh",
6121 .data = &ip6_dst_ops_template.gc_thresh,
6122 .maxlen = sizeof(int),
6123 .mode = 0644,
6124 .proc_handler = proc_dointvec,
6125 },
6126 {
6127 .procname = "max_size",
6128 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
6129 .maxlen = sizeof(int),
6130 .mode = 0644,
6131 .proc_handler = proc_dointvec,
6132 },
6133 {
6134 .procname = "gc_min_interval",
6135 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6136 .maxlen = sizeof(int),
6137 .mode = 0644,
6138 .proc_handler = proc_dointvec_jiffies,
6139 },
6140 {
6141 .procname = "gc_timeout",
6142 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
6143 .maxlen = sizeof(int),
6144 .mode = 0644,
6145 .proc_handler = proc_dointvec_jiffies,
6146 },
6147 {
6148 .procname = "gc_interval",
6149 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
6150 .maxlen = sizeof(int),
6151 .mode = 0644,
6152 .proc_handler = proc_dointvec_jiffies,
6153 },
6154 {
6155 .procname = "gc_elasticity",
6156 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
6157 .maxlen = sizeof(int),
6158 .mode = 0644,
6159 .proc_handler = proc_dointvec,
6160 },
6161 {
6162 .procname = "mtu_expires",
6163 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
6164 .maxlen = sizeof(int),
6165 .mode = 0644,
6166 .proc_handler = proc_dointvec_jiffies,
6167 },
6168 {
6169 .procname = "min_adv_mss",
6170 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
6171 .maxlen = sizeof(int),
6172 .mode = 0644,
6173 .proc_handler = proc_dointvec,
6174 },
6175 {
6176 .procname = "gc_min_interval_ms",
6177 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
6178 .maxlen = sizeof(int),
6179 .mode = 0644,
6180 .proc_handler = proc_dointvec_ms_jiffies,
6181 },
6182 {
6183 .procname = "skip_notify_on_dev_down",
6184 .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down,
6185 .maxlen = sizeof(int),
6186 .mode = 0644,
6187 .proc_handler = proc_dointvec_minmax,
6188 .extra1 = SYSCTL_ZERO,
6189 .extra2 = SYSCTL_ONE,
6190 },
6191 { }
6192 };
6193
6194 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
6195 {
6196 struct ctl_table *table;
6197
6198 table = kmemdup(ipv6_route_table_template,
6199 sizeof(ipv6_route_table_template),
6200 GFP_KERNEL);
6201
6202 if (table) {
6203 table[0].data = &net->ipv6.sysctl.flush_delay;
6204 table[0].extra1 = net;
6205 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
6206 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
6207 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6208 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
6209 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
6210 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
6211 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
6212 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
6213 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
6214 table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
6215
6216 /* Don't export sysctls to unprivileged users */
6217 if (net->user_ns != &init_user_ns)
6218 table[0].procname = NULL;
6219 }
6220
6221 return table;
6222 }
6223 #endif
6224
6225 static int __net_init ip6_route_net_init(struct net *net)
6226 {
6227 int ret = -ENOMEM;
6228
6229 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
6230 sizeof(net->ipv6.ip6_dst_ops));
6231
6232 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
6233 goto out_ip6_dst_ops;
6234
6235 net->ipv6.fib6_null_entry = fib6_info_alloc(GFP_KERNEL, true);
6236 if (!net->ipv6.fib6_null_entry)
6237 goto out_ip6_dst_entries;
6238 memcpy(net->ipv6.fib6_null_entry, &fib6_null_entry_template,
6239 sizeof(*net->ipv6.fib6_null_entry));
6240
6241 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
6242 sizeof(*net->ipv6.ip6_null_entry),
6243 GFP_KERNEL);
6244 if (!net->ipv6.ip6_null_entry)
6245 goto out_fib6_null_entry;
6246 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6247 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
6248 ip6_template_metrics, true);
6249 INIT_LIST_HEAD(&net->ipv6.ip6_null_entry->rt6i_uncached);
6250
6251 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6252 net->ipv6.fib6_has_custom_rules = false;
6253 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
6254 sizeof(*net->ipv6.ip6_prohibit_entry),
6255 GFP_KERNEL);
6256 if (!net->ipv6.ip6_prohibit_entry)
6257 goto out_ip6_null_entry;
6258 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6259 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
6260 ip6_template_metrics, true);
6261 INIT_LIST_HEAD(&net->ipv6.ip6_prohibit_entry->rt6i_uncached);
6262
6263 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
6264 sizeof(*net->ipv6.ip6_blk_hole_entry),
6265 GFP_KERNEL);
6266 if (!net->ipv6.ip6_blk_hole_entry)
6267 goto out_ip6_prohibit_entry;
6268 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
6269 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
6270 ip6_template_metrics, true);
6271 INIT_LIST_HEAD(&net->ipv6.ip6_blk_hole_entry->rt6i_uncached);
6272 #ifdef CONFIG_IPV6_SUBTREES
6273 net->ipv6.fib6_routes_require_src = 0;
6274 #endif
6275 #endif
6276
6277 net->ipv6.sysctl.flush_delay = 0;
6278 net->ipv6.sysctl.ip6_rt_max_size = 4096;
6279 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
6280 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
6281 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
6282 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
6283 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
6284 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
6285 net->ipv6.sysctl.skip_notify_on_dev_down = 0;
6286
6287 net->ipv6.ip6_rt_gc_expire = 30*HZ;
6288
6289 ret = 0;
6290 out:
6291 return ret;
6292
6293 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6294 out_ip6_prohibit_entry:
6295 kfree(net->ipv6.ip6_prohibit_entry);
6296 out_ip6_null_entry:
6297 kfree(net->ipv6.ip6_null_entry);
6298 #endif
6299 out_fib6_null_entry:
6300 kfree(net->ipv6.fib6_null_entry);
6301 out_ip6_dst_entries:
6302 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6303 out_ip6_dst_ops:
6304 goto out;
6305 }
6306
6307 static void __net_exit ip6_route_net_exit(struct net *net)
6308 {
6309 kfree(net->ipv6.fib6_null_entry);
6310 kfree(net->ipv6.ip6_null_entry);
6311 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6312 kfree(net->ipv6.ip6_prohibit_entry);
6313 kfree(net->ipv6.ip6_blk_hole_entry);
6314 #endif
6315 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
6316 }
6317
6318 static int __net_init ip6_route_net_init_late(struct net *net)
6319 {
6320 #ifdef CONFIG_PROC_FS
6321 proc_create_net("ipv6_route", 0, net->proc_net, &ipv6_route_seq_ops,
6322 sizeof(struct ipv6_route_iter));
6323 proc_create_net_single("rt6_stats", 0444, net->proc_net,
6324 rt6_stats_seq_show, NULL);
6325 #endif
6326 return 0;
6327 }
6328
6329 static void __net_exit ip6_route_net_exit_late(struct net *net)
6330 {
6331 #ifdef CONFIG_PROC_FS
6332 remove_proc_entry("ipv6_route", net->proc_net);
6333 remove_proc_entry("rt6_stats", net->proc_net);
6334 #endif
6335 }
6336
6337 static struct pernet_operations ip6_route_net_ops = {
6338 .init = ip6_route_net_init,
6339 .exit = ip6_route_net_exit,
6340 };
6341
6342 static int __net_init ipv6_inetpeer_init(struct net *net)
6343 {
6344 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
6345
6346 if (!bp)
6347 return -ENOMEM;
6348 inet_peer_base_init(bp);
6349 net->ipv6.peers = bp;
6350 return 0;
6351 }
6352
6353 static void __net_exit ipv6_inetpeer_exit(struct net *net)
6354 {
6355 struct inet_peer_base *bp = net->ipv6.peers;
6356
6357 net->ipv6.peers = NULL;
6358 inetpeer_invalidate_tree(bp);
6359 kfree(bp);
6360 }
6361
6362 static struct pernet_operations ipv6_inetpeer_ops = {
6363 .init = ipv6_inetpeer_init,
6364 .exit = ipv6_inetpeer_exit,
6365 };
6366
6367 static struct pernet_operations ip6_route_net_late_ops = {
6368 .init = ip6_route_net_init_late,
6369 .exit = ip6_route_net_exit_late,
6370 };
6371
6372 static struct notifier_block ip6_route_dev_notifier = {
6373 .notifier_call = ip6_route_dev_notify,
6374 .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
6375 };
6376
6377 void __init ip6_route_init_special_entries(void)
6378 {
6379 /* Registering of the loopback is done before this portion of code,
6380 * the loopback reference in rt6_info will not be taken, do it
6381 * manually for init_net */
6382 init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev;
6383 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
6384 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6385 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
6386 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
6387 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6388 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
6389 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
6390 #endif
6391 }
6392
6393 int __init ip6_route_init(void)
6394 {
6395 int ret;
6396 int cpu;
6397
6398 ret = -ENOMEM;
6399 ip6_dst_ops_template.kmem_cachep =
6400 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
6401 SLAB_HWCACHE_ALIGN, NULL);
6402 if (!ip6_dst_ops_template.kmem_cachep)
6403 goto out;
6404
6405 ret = dst_entries_init(&ip6_dst_blackhole_ops);
6406 if (ret)
6407 goto out_kmem_cache;
6408
6409 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
6410 if (ret)
6411 goto out_dst_entries;
6412
6413 ret = register_pernet_subsys(&ip6_route_net_ops);
6414 if (ret)
6415 goto out_register_inetpeer;
6416
6417 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
6418
6419 ret = fib6_init();
6420 if (ret)
6421 goto out_register_subsys;
6422
6423 ret = xfrm6_init();
6424 if (ret)
6425 goto out_fib6_init;
6426
6427 ret = fib6_rules_init();
6428 if (ret)
6429 goto xfrm6_init;
6430
6431 ret = register_pernet_subsys(&ip6_route_net_late_ops);
6432 if (ret)
6433 goto fib6_rules_init;
6434
6435 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWROUTE,
6436 inet6_rtm_newroute, NULL, 0);
6437 if (ret < 0)
6438 goto out_register_late_subsys;
6439
6440 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELROUTE,
6441 inet6_rtm_delroute, NULL, 0);
6442 if (ret < 0)
6443 goto out_register_late_subsys;
6444
6445 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE,
6446 inet6_rtm_getroute, NULL,
6447 RTNL_FLAG_DOIT_UNLOCKED);
6448 if (ret < 0)
6449 goto out_register_late_subsys;
6450
6451 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
6452 if (ret)
6453 goto out_register_late_subsys;
6454
6455 for_each_possible_cpu(cpu) {
6456 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
6457
6458 INIT_LIST_HEAD(&ul->head);
6459 spin_lock_init(&ul->lock);
6460 }
6461
6462 out:
6463 return ret;
6464
6465 out_register_late_subsys:
6466 rtnl_unregister_all(PF_INET6);
6467 unregister_pernet_subsys(&ip6_route_net_late_ops);
6468 fib6_rules_init:
6469 fib6_rules_cleanup();
6470 xfrm6_init:
6471 xfrm6_fini();
6472 out_fib6_init:
6473 fib6_gc_cleanup();
6474 out_register_subsys:
6475 unregister_pernet_subsys(&ip6_route_net_ops);
6476 out_register_inetpeer:
6477 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6478 out_dst_entries:
6479 dst_entries_destroy(&ip6_dst_blackhole_ops);
6480 out_kmem_cache:
6481 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6482 goto out;
6483 }
6484
6485 void ip6_route_cleanup(void)
6486 {
6487 unregister_netdevice_notifier(&ip6_route_dev_notifier);
6488 unregister_pernet_subsys(&ip6_route_net_late_ops);
6489 fib6_rules_cleanup();
6490 xfrm6_fini();
6491 fib6_gc_cleanup();
6492 unregister_pernet_subsys(&ipv6_inetpeer_ops);
6493 unregister_pernet_subsys(&ip6_route_net_ops);
6494 dst_entries_destroy(&ip6_dst_blackhole_ops);
6495 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
6496 }
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