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perf bpf: Move perf_event_output() from stdio.h to bpf.h
[linux/fpc-iii.git] / net / ipv6 / route.c
blob059f0531f7c1c86133afcab0f8e7388c60eeaf58
1 /*
2 * Linux INET6 implementation
3 * FIB front-end.
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14 /* Changes:
15 *
16 * YOSHIFUJI Hideaki @USAGI
17 * reworked default router selection.
18 * - respect outgoing interface
19 * - select from (probably) reachable routers (i.e.
20 * routers in REACHABLE, STALE, DELAY or PROBE states).
21 * - always select the same router if it is (probably)
22 * reachable. otherwise, round-robin the list.
23 * Ville Nuorvala
24 * Fixed routing subtrees.
25 */
26
27 #define pr_fmt(fmt) "IPv6: " fmt
28
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/export.h>
32 #include <linux/types.h>
33 #include <linux/times.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <linux/net.h>
37 #include <linux/route.h>
38 #include <linux/netdevice.h>
39 #include <linux/in6.h>
40 #include <linux/mroute6.h>
41 #include <linux/init.h>
42 #include <linux/if_arp.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/nsproxy.h>
46 #include <linux/slab.h>
47 #include <linux/jhash.h>
48 #include <net/net_namespace.h>
49 #include <net/snmp.h>
50 #include <net/ipv6.h>
51 #include <net/ip6_fib.h>
52 #include <net/ip6_route.h>
53 #include <net/ndisc.h>
54 #include <net/addrconf.h>
55 #include <net/tcp.h>
56 #include <linux/rtnetlink.h>
57 #include <net/dst.h>
58 #include <net/dst_metadata.h>
59 #include <net/xfrm.h>
60 #include <net/netevent.h>
61 #include <net/netlink.h>
62 #include <net/nexthop.h>
63 #include <net/lwtunnel.h>
64 #include <net/ip_tunnels.h>
65 #include <net/l3mdev.h>
66 #include <net/ip.h>
67 #include <linux/uaccess.h>
68
69 #ifdef CONFIG_SYSCTL
70 #include <linux/sysctl.h>
71 #endif
72
73 static int ip6_rt_type_to_error(u8 fib6_type);
74
75 #define CREATE_TRACE_POINTS
76 #include <trace/events/fib6.h>
77 EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup);
78 #undef CREATE_TRACE_POINTS
79
80 enum rt6_nud_state {
81 RT6_NUD_FAIL_HARD = -3,
82 RT6_NUD_FAIL_PROBE = -2,
83 RT6_NUD_FAIL_DO_RR = -1,
84 RT6_NUD_SUCCEED = 1
85 };
86
87 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
88 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
89 static unsigned int ip6_mtu(const struct dst_entry *dst);
90 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
91 static void ip6_dst_destroy(struct dst_entry *);
92 static void ip6_dst_ifdown(struct dst_entry *,
93 struct net_device *dev, int how);
94 static int ip6_dst_gc(struct dst_ops *ops);
95
96 static int ip6_pkt_discard(struct sk_buff *skb);
97 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
98 static int ip6_pkt_prohibit(struct sk_buff *skb);
99 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
100 static void ip6_link_failure(struct sk_buff *skb);
101 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
102 struct sk_buff *skb, u32 mtu);
103 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
104 struct sk_buff *skb);
105 static int rt6_score_route(struct fib6_info *rt, int oif, int strict);
106 static size_t rt6_nlmsg_size(struct fib6_info *rt);
107 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
108 struct fib6_info *rt, struct dst_entry *dst,
109 struct in6_addr *dest, struct in6_addr *src,
110 int iif, int type, u32 portid, u32 seq,
111 unsigned int flags);
112 static struct rt6_info *rt6_find_cached_rt(struct fib6_info *rt,
113 struct in6_addr *daddr,
114 struct in6_addr *saddr);
115
116 #ifdef CONFIG_IPV6_ROUTE_INFO
117 static struct fib6_info *rt6_add_route_info(struct net *net,
118 const struct in6_addr *prefix, int prefixlen,
119 const struct in6_addr *gwaddr,
120 struct net_device *dev,
121 unsigned int pref);
122 static struct fib6_info *rt6_get_route_info(struct net *net,
123 const struct in6_addr *prefix, int prefixlen,
124 const struct in6_addr *gwaddr,
125 struct net_device *dev);
126 #endif
127
128 struct uncached_list {
129 spinlock_t lock;
130 struct list_head head;
131 };
132
133 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
134
135 void rt6_uncached_list_add(struct rt6_info *rt)
136 {
137 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
138
139 rt->rt6i_uncached_list = ul;
140
141 spin_lock_bh(&ul->lock);
142 list_add_tail(&rt->rt6i_uncached, &ul->head);
143 spin_unlock_bh(&ul->lock);
144 }
145
146 void rt6_uncached_list_del(struct rt6_info *rt)
147 {
148 if (!list_empty(&rt->rt6i_uncached)) {
149 struct uncached_list *ul = rt->rt6i_uncached_list;
150 struct net *net = dev_net(rt->dst.dev);
151
152 spin_lock_bh(&ul->lock);
153 list_del(&rt->rt6i_uncached);
154 atomic_dec(&net->ipv6.rt6_stats->fib_rt_uncache);
155 spin_unlock_bh(&ul->lock);
156 }
157 }
158
159 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
160 {
161 struct net_device *loopback_dev = net->loopback_dev;
162 int cpu;
163
164 if (dev == loopback_dev)
165 return;
166
167 for_each_possible_cpu(cpu) {
168 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
169 struct rt6_info *rt;
170
171 spin_lock_bh(&ul->lock);
172 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
173 struct inet6_dev *rt_idev = rt->rt6i_idev;
174 struct net_device *rt_dev = rt->dst.dev;
175
176 if (rt_idev->dev == dev) {
177 rt->rt6i_idev = in6_dev_get(loopback_dev);
178 in6_dev_put(rt_idev);
179 }
180
181 if (rt_dev == dev) {
182 rt->dst.dev = loopback_dev;
183 dev_hold(rt->dst.dev);
184 dev_put(rt_dev);
185 }
186 }
187 spin_unlock_bh(&ul->lock);
188 }
189 }
190
191 static inline const void *choose_neigh_daddr(const struct in6_addr *p,
192 struct sk_buff *skb,
193 const void *daddr)
194 {
195 if (!ipv6_addr_any(p))
196 return (const void *) p;
197 else if (skb)
198 return &ipv6_hdr(skb)->daddr;
199 return daddr;
200 }
201
202 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
203 struct net_device *dev,
204 struct sk_buff *skb,
205 const void *daddr)
206 {
207 struct neighbour *n;
208
209 daddr = choose_neigh_daddr(gw, skb, daddr);
210 n = __ipv6_neigh_lookup(dev, daddr);
211 if (n)
212 return n;
213 return neigh_create(&nd_tbl, daddr, dev);
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(&rt->rt6i_gateway, dst->dev, skb, daddr);
223 }
224
225 static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr)
226 {
227 struct net_device *dev = dst->dev;
228 struct rt6_info *rt = (struct rt6_info *)dst;
229
230 daddr = choose_neigh_daddr(&rt->rt6i_gateway, NULL, daddr);
231 if (!daddr)
232 return;
233 if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
234 return;
235 if (ipv6_addr_is_multicast((const struct in6_addr *)daddr))
236 return;
237 __ipv6_confirm_neigh(dev, daddr);
238 }
239
240 static struct dst_ops ip6_dst_ops_template = {
241 .family = AF_INET6,
242 .gc = ip6_dst_gc,
243 .gc_thresh = 1024,
244 .check = ip6_dst_check,
245 .default_advmss = ip6_default_advmss,
246 .mtu = ip6_mtu,
247 .cow_metrics = dst_cow_metrics_generic,
248 .destroy = ip6_dst_destroy,
249 .ifdown = ip6_dst_ifdown,
250 .negative_advice = ip6_negative_advice,
251 .link_failure = ip6_link_failure,
252 .update_pmtu = ip6_rt_update_pmtu,
253 .redirect = rt6_do_redirect,
254 .local_out = __ip6_local_out,
255 .neigh_lookup = ip6_dst_neigh_lookup,
256 .confirm_neigh = ip6_confirm_neigh,
257 };
258
259 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
260 {
261 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
262
263 return mtu ? : dst->dev->mtu;
264 }
265
266 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
267 struct sk_buff *skb, u32 mtu)
268 {
269 }
270
271 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
272 struct sk_buff *skb)
273 {
274 }
275
276 static struct dst_ops ip6_dst_blackhole_ops = {
277 .family = AF_INET6,
278 .destroy = ip6_dst_destroy,
279 .check = ip6_dst_check,
280 .mtu = ip6_blackhole_mtu,
281 .default_advmss = ip6_default_advmss,
282 .update_pmtu = ip6_rt_blackhole_update_pmtu,
283 .redirect = ip6_rt_blackhole_redirect,
284 .cow_metrics = dst_cow_metrics_generic,
285 .neigh_lookup = ip6_dst_neigh_lookup,
286 };
287
288 static const u32 ip6_template_metrics[RTAX_MAX] = {
289 [RTAX_HOPLIMIT - 1] = 0,
290 };
291
292 static const struct fib6_info fib6_null_entry_template = {
293 .fib6_flags = (RTF_REJECT | RTF_NONEXTHOP),
294 .fib6_protocol = RTPROT_KERNEL,
295 .fib6_metric = ~(u32)0,
296 .fib6_ref = ATOMIC_INIT(1),
297 .fib6_type = RTN_UNREACHABLE,
298 .fib6_metrics = (struct dst_metrics *)&dst_default_metrics,
299 };
300
301 static const struct rt6_info ip6_null_entry_template = {
302 .dst = {
303 .__refcnt = ATOMIC_INIT(1),
304 .__use = 1,
305 .obsolete = DST_OBSOLETE_FORCE_CHK,
306 .error = -ENETUNREACH,
307 .input = ip6_pkt_discard,
308 .output = ip6_pkt_discard_out,
309 },
310 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
311 };
312
313 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
314
315 static const struct rt6_info ip6_prohibit_entry_template = {
316 .dst = {
317 .__refcnt = ATOMIC_INIT(1),
318 .__use = 1,
319 .obsolete = DST_OBSOLETE_FORCE_CHK,
320 .error = -EACCES,
321 .input = ip6_pkt_prohibit,
322 .output = ip6_pkt_prohibit_out,
323 },
324 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
325 };
326
327 static const struct rt6_info ip6_blk_hole_entry_template = {
328 .dst = {
329 .__refcnt = ATOMIC_INIT(1),
330 .__use = 1,
331 .obsolete = DST_OBSOLETE_FORCE_CHK,
332 .error = -EINVAL,
333 .input = dst_discard,
334 .output = dst_discard_out,
335 },
336 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
337 };
338
339 #endif
340
341 static void rt6_info_init(struct rt6_info *rt)
342 {
343 struct dst_entry *dst = &rt->dst;
344
345 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
346 INIT_LIST_HEAD(&rt->rt6i_uncached);
347 }
348
349 /* allocate dst with ip6_dst_ops */
350 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
351 int flags)
352 {
353 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
354 1, DST_OBSOLETE_FORCE_CHK, flags);
355
356 if (rt) {
357 rt6_info_init(rt);
358 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
359 }
360
361 return rt;
362 }
363 EXPORT_SYMBOL(ip6_dst_alloc);
364
365 static void ip6_dst_destroy(struct dst_entry *dst)
366 {
367 struct rt6_info *rt = (struct rt6_info *)dst;
368 struct fib6_info *from;
369 struct inet6_dev *idev;
370
371 ip_dst_metrics_put(dst);
372 rt6_uncached_list_del(rt);
373
374 idev = rt->rt6i_idev;
375 if (idev) {
376 rt->rt6i_idev = NULL;
377 in6_dev_put(idev);
378 }
379
380 rcu_read_lock();
381 from = rcu_dereference(rt->from);
382 rcu_assign_pointer(rt->from, NULL);
383 fib6_info_release(from);
384 rcu_read_unlock();
385 }
386
387 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
388 int how)
389 {
390 struct rt6_info *rt = (struct rt6_info *)dst;
391 struct inet6_dev *idev = rt->rt6i_idev;
392 struct net_device *loopback_dev =
393 dev_net(dev)->loopback_dev;
394
395 if (idev && idev->dev != loopback_dev) {
396 struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
397 if (loopback_idev) {
398 rt->rt6i_idev = loopback_idev;
399 in6_dev_put(idev);
400 }
401 }
402 }
403
404 static bool __rt6_check_expired(const struct rt6_info *rt)
405 {
406 if (rt->rt6i_flags & RTF_EXPIRES)
407 return time_after(jiffies, rt->dst.expires);
408 else
409 return false;
410 }
411
412 static bool rt6_check_expired(const struct rt6_info *rt)
413 {
414 struct fib6_info *from;
415
416 from = rcu_dereference(rt->from);
417
418 if (rt->rt6i_flags & RTF_EXPIRES) {
419 if (time_after(jiffies, rt->dst.expires))
420 return true;
421 } else if (from) {
422 return rt->dst.obsolete != DST_OBSOLETE_FORCE_CHK ||
423 fib6_check_expired(from);
424 }
425 return false;
426 }
427
428 struct fib6_info *fib6_multipath_select(const struct net *net,
429 struct fib6_info *match,
430 struct flowi6 *fl6, int oif,
431 const struct sk_buff *skb,
432 int strict)
433 {
434 struct fib6_info *sibling, *next_sibling;
435
436 /* We might have already computed the hash for ICMPv6 errors. In such
437 * case it will always be non-zero. Otherwise now is the time to do it.
438 */
439 if (!fl6->mp_hash)
440 fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL);
441
442 if (fl6->mp_hash <= atomic_read(&match->fib6_nh.nh_upper_bound))
443 return match;
444
445 list_for_each_entry_safe(sibling, next_sibling, &match->fib6_siblings,
446 fib6_siblings) {
447 int nh_upper_bound;
448
449 nh_upper_bound = atomic_read(&sibling->fib6_nh.nh_upper_bound);
450 if (fl6->mp_hash > nh_upper_bound)
451 continue;
452 if (rt6_score_route(sibling, oif, strict) < 0)
453 break;
454 match = sibling;
455 break;
456 }
457
458 return match;
459 }
460
461 /*
462 * Route lookup. rcu_read_lock() should be held.
463 */
464
465 static inline struct fib6_info *rt6_device_match(struct net *net,
466 struct fib6_info *rt,
467 const struct in6_addr *saddr,
468 int oif,
469 int flags)
470 {
471 struct fib6_info *sprt;
472
473 if (!oif && ipv6_addr_any(saddr) &&
474 !(rt->fib6_nh.nh_flags & RTNH_F_DEAD))
475 return rt;
476
477 for (sprt = rt; sprt; sprt = rcu_dereference(sprt->fib6_next)) {
478 const struct net_device *dev = sprt->fib6_nh.nh_dev;
479
480 if (sprt->fib6_nh.nh_flags & RTNH_F_DEAD)
481 continue;
482
483 if (oif) {
484 if (dev->ifindex == oif)
485 return sprt;
486 } else {
487 if (ipv6_chk_addr(net, saddr, dev,
488 flags & RT6_LOOKUP_F_IFACE))
489 return sprt;
490 }
491 }
492
493 if (oif && flags & RT6_LOOKUP_F_IFACE)
494 return net->ipv6.fib6_null_entry;
495
496 return rt->fib6_nh.nh_flags & RTNH_F_DEAD ? net->ipv6.fib6_null_entry : rt;
497 }
498
499 #ifdef CONFIG_IPV6_ROUTER_PREF
500 struct __rt6_probe_work {
501 struct work_struct work;
502 struct in6_addr target;
503 struct net_device *dev;
504 };
505
506 static void rt6_probe_deferred(struct work_struct *w)
507 {
508 struct in6_addr mcaddr;
509 struct __rt6_probe_work *work =
510 container_of(w, struct __rt6_probe_work, work);
511
512 addrconf_addr_solict_mult(&work->target, &mcaddr);
513 ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
514 dev_put(work->dev);
515 kfree(work);
516 }
517
518 static void rt6_probe(struct fib6_info *rt)
519 {
520 struct __rt6_probe_work *work = NULL;
521 const struct in6_addr *nh_gw;
522 struct neighbour *neigh;
523 struct net_device *dev;
524 struct inet6_dev *idev;
525
526 /*
527 * Okay, this does not seem to be appropriate
528 * for now, however, we need to check if it
529 * is really so; aka Router Reachability Probing.
530 *
531 * Router Reachability Probe MUST be rate-limited
532 * to no more than one per minute.
533 */
534 if (!rt || !(rt->fib6_flags & RTF_GATEWAY))
535 return;
536
537 nh_gw = &rt->fib6_nh.nh_gw;
538 dev = rt->fib6_nh.nh_dev;
539 rcu_read_lock_bh();
540 idev = __in6_dev_get(dev);
541 neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
542 if (neigh) {
543 if (neigh->nud_state & NUD_VALID)
544 goto out;
545
546 write_lock(&neigh->lock);
547 if (!(neigh->nud_state & NUD_VALID) &&
548 time_after(jiffies,
549 neigh->updated + idev->cnf.rtr_probe_interval)) {
550 work = kmalloc(sizeof(*work), GFP_ATOMIC);
551 if (work)
552 __neigh_set_probe_once(neigh);
553 }
554 write_unlock(&neigh->lock);
555 } else if (time_after(jiffies, rt->last_probe +
556 idev->cnf.rtr_probe_interval)) {
557 work = kmalloc(sizeof(*work), GFP_ATOMIC);
558 }
559
560 if (work) {
561 rt->last_probe = jiffies;
562 INIT_WORK(&work->work, rt6_probe_deferred);
563 work->target = *nh_gw;
564 dev_hold(dev);
565 work->dev = dev;
566 schedule_work(&work->work);
567 }
568
569 out:
570 rcu_read_unlock_bh();
571 }
572 #else
573 static inline void rt6_probe(struct fib6_info *rt)
574 {
575 }
576 #endif
577
578 /*
579 * Default Router Selection (RFC 2461 6.3.6)
580 */
581 static inline int rt6_check_dev(struct fib6_info *rt, int oif)
582 {
583 const struct net_device *dev = rt->fib6_nh.nh_dev;
584
585 if (!oif || dev->ifindex == oif)
586 return 2;
587 return 0;
588 }
589
590 static inline enum rt6_nud_state rt6_check_neigh(struct fib6_info *rt)
591 {
592 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
593 struct neighbour *neigh;
594
595 if (rt->fib6_flags & RTF_NONEXTHOP ||
596 !(rt->fib6_flags & RTF_GATEWAY))
597 return RT6_NUD_SUCCEED;
598
599 rcu_read_lock_bh();
600 neigh = __ipv6_neigh_lookup_noref(rt->fib6_nh.nh_dev,
601 &rt->fib6_nh.nh_gw);
602 if (neigh) {
603 read_lock(&neigh->lock);
604 if (neigh->nud_state & NUD_VALID)
605 ret = RT6_NUD_SUCCEED;
606 #ifdef CONFIG_IPV6_ROUTER_PREF
607 else if (!(neigh->nud_state & NUD_FAILED))
608 ret = RT6_NUD_SUCCEED;
609 else
610 ret = RT6_NUD_FAIL_PROBE;
611 #endif
612 read_unlock(&neigh->lock);
613 } else {
614 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
615 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
616 }
617 rcu_read_unlock_bh();
618
619 return ret;
620 }
621
622 static int rt6_score_route(struct fib6_info *rt, int oif, int strict)
623 {
624 int m;
625
626 m = rt6_check_dev(rt, oif);
627 if (!m && (strict & RT6_LOOKUP_F_IFACE))
628 return RT6_NUD_FAIL_HARD;
629 #ifdef CONFIG_IPV6_ROUTER_PREF
630 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->fib6_flags)) << 2;
631 #endif
632 if (strict & RT6_LOOKUP_F_REACHABLE) {
633 int n = rt6_check_neigh(rt);
634 if (n < 0)
635 return n;
636 }
637 return m;
638 }
639
640 /* called with rc_read_lock held */
641 static inline bool fib6_ignore_linkdown(const struct fib6_info *f6i)
642 {
643 const struct net_device *dev = fib6_info_nh_dev(f6i);
644 bool rc = false;
645
646 if (dev) {
647 const struct inet6_dev *idev = __in6_dev_get(dev);
648
649 rc = !!idev->cnf.ignore_routes_with_linkdown;
650 }
651
652 return rc;
653 }
654
655 static struct fib6_info *find_match(struct fib6_info *rt, int oif, int strict,
656 int *mpri, struct fib6_info *match,
657 bool *do_rr)
658 {
659 int m;
660 bool match_do_rr = false;
661
662 if (rt->fib6_nh.nh_flags & RTNH_F_DEAD)
663 goto out;
664
665 if (fib6_ignore_linkdown(rt) &&
666 rt->fib6_nh.nh_flags & RTNH_F_LINKDOWN &&
667 !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
668 goto out;
669
670 if (fib6_check_expired(rt))
671 goto out;
672
673 m = rt6_score_route(rt, oif, strict);
674 if (m == RT6_NUD_FAIL_DO_RR) {
675 match_do_rr = true;
676 m = 0; /* lowest valid score */
677 } else if (m == RT6_NUD_FAIL_HARD) {
678 goto out;
679 }
680
681 if (strict & RT6_LOOKUP_F_REACHABLE)
682 rt6_probe(rt);
683
684 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
685 if (m > *mpri) {
686 *do_rr = match_do_rr;
687 *mpri = m;
688 match = rt;
689 }
690 out:
691 return match;
692 }
693
694 static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
695 struct fib6_info *leaf,
696 struct fib6_info *rr_head,
697 u32 metric, int oif, int strict,
698 bool *do_rr)
699 {
700 struct fib6_info *rt, *match, *cont;
701 int mpri = -1;
702
703 match = NULL;
704 cont = NULL;
705 for (rt = rr_head; rt; rt = rcu_dereference(rt->fib6_next)) {
706 if (rt->fib6_metric != metric) {
707 cont = rt;
708 break;
709 }
710
711 match = find_match(rt, oif, strict, &mpri, match, do_rr);
712 }
713
714 for (rt = leaf; rt && rt != rr_head;
715 rt = rcu_dereference(rt->fib6_next)) {
716 if (rt->fib6_metric != metric) {
717 cont = rt;
718 break;
719 }
720
721 match = find_match(rt, oif, strict, &mpri, match, do_rr);
722 }
723
724 if (match || !cont)
725 return match;
726
727 for (rt = cont; rt; rt = rcu_dereference(rt->fib6_next))
728 match = find_match(rt, oif, strict, &mpri, match, do_rr);
729
730 return match;
731 }
732
733 static struct fib6_info *rt6_select(struct net *net, struct fib6_node *fn,
734 int oif, int strict)
735 {
736 struct fib6_info *leaf = rcu_dereference(fn->leaf);
737 struct fib6_info *match, *rt0;
738 bool do_rr = false;
739 int key_plen;
740
741 if (!leaf || leaf == net->ipv6.fib6_null_entry)
742 return net->ipv6.fib6_null_entry;
743
744 rt0 = rcu_dereference(fn->rr_ptr);
745 if (!rt0)
746 rt0 = leaf;
747
748 /* Double check to make sure fn is not an intermediate node
749 * and fn->leaf does not points to its child's leaf
750 * (This might happen if all routes under fn are deleted from
751 * the tree and fib6_repair_tree() is called on the node.)
752 */
753 key_plen = rt0->fib6_dst.plen;
754 #ifdef CONFIG_IPV6_SUBTREES
755 if (rt0->fib6_src.plen)
756 key_plen = rt0->fib6_src.plen;
757 #endif
758 if (fn->fn_bit != key_plen)
759 return net->ipv6.fib6_null_entry;
760
761 match = find_rr_leaf(fn, leaf, rt0, rt0->fib6_metric, oif, strict,
762 &do_rr);
763
764 if (do_rr) {
765 struct fib6_info *next = rcu_dereference(rt0->fib6_next);
766
767 /* no entries matched; do round-robin */
768 if (!next || next->fib6_metric != rt0->fib6_metric)
769 next = leaf;
770
771 if (next != rt0) {
772 spin_lock_bh(&leaf->fib6_table->tb6_lock);
773 /* make sure next is not being deleted from the tree */
774 if (next->fib6_node)
775 rcu_assign_pointer(fn->rr_ptr, next);
776 spin_unlock_bh(&leaf->fib6_table->tb6_lock);
777 }
778 }
779
780 return match ? match : net->ipv6.fib6_null_entry;
781 }
782
783 static bool rt6_is_gw_or_nonexthop(const struct fib6_info *rt)
784 {
785 return (rt->fib6_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
786 }
787
788 #ifdef CONFIG_IPV6_ROUTE_INFO
789 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
790 const struct in6_addr *gwaddr)
791 {
792 struct net *net = dev_net(dev);
793 struct route_info *rinfo = (struct route_info *) opt;
794 struct in6_addr prefix_buf, *prefix;
795 unsigned int pref;
796 unsigned long lifetime;
797 struct fib6_info *rt;
798
799 if (len < sizeof(struct route_info)) {
800 return -EINVAL;
801 }
802
803 /* Sanity check for prefix_len and length */
804 if (rinfo->length > 3) {
805 return -EINVAL;
806 } else if (rinfo->prefix_len > 128) {
807 return -EINVAL;
808 } else if (rinfo->prefix_len > 64) {
809 if (rinfo->length < 2) {
810 return -EINVAL;
811 }
812 } else if (rinfo->prefix_len > 0) {
813 if (rinfo->length < 1) {
814 return -EINVAL;
815 }
816 }
817
818 pref = rinfo->route_pref;
819 if (pref == ICMPV6_ROUTER_PREF_INVALID)
820 return -EINVAL;
821
822 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
823
824 if (rinfo->length == 3)
825 prefix = (struct in6_addr *)rinfo->prefix;
826 else {
827 /* this function is safe */
828 ipv6_addr_prefix(&prefix_buf,
829 (struct in6_addr *)rinfo->prefix,
830 rinfo->prefix_len);
831 prefix = &prefix_buf;
832 }
833
834 if (rinfo->prefix_len == 0)
835 rt = rt6_get_dflt_router(net, gwaddr, dev);
836 else
837 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
838 gwaddr, dev);
839
840 if (rt && !lifetime) {
841 ip6_del_rt(net, rt);
842 rt = NULL;
843 }
844
845 if (!rt && lifetime)
846 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
847 dev, pref);
848 else if (rt)
849 rt->fib6_flags = RTF_ROUTEINFO |
850 (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
851
852 if (rt) {
853 if (!addrconf_finite_timeout(lifetime))
854 fib6_clean_expires(rt);
855 else
856 fib6_set_expires(rt, jiffies + HZ * lifetime);
857
858 fib6_info_release(rt);
859 }
860 return 0;
861 }
862 #endif
863
864 /*
865 * Misc support functions
866 */
867
868 /* called with rcu_lock held */
869 static struct net_device *ip6_rt_get_dev_rcu(struct fib6_info *rt)
870 {
871 struct net_device *dev = rt->fib6_nh.nh_dev;
872
873 if (rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) {
874 /* for copies of local routes, dst->dev needs to be the
875 * device if it is a master device, the master device if
876 * device is enslaved, and the loopback as the default
877 */
878 if (netif_is_l3_slave(dev) &&
879 !rt6_need_strict(&rt->fib6_dst.addr))
880 dev = l3mdev_master_dev_rcu(dev);
881 else if (!netif_is_l3_master(dev))
882 dev = dev_net(dev)->loopback_dev;
883 /* last case is netif_is_l3_master(dev) is true in which
884 * case we want dev returned to be dev
885 */
886 }
887
888 return dev;
889 }
890
891 static const int fib6_prop[RTN_MAX + 1] = {
892 [RTN_UNSPEC] = 0,
893 [RTN_UNICAST] = 0,
894 [RTN_LOCAL] = 0,
895 [RTN_BROADCAST] = 0,
896 [RTN_ANYCAST] = 0,
897 [RTN_MULTICAST] = 0,
898 [RTN_BLACKHOLE] = -EINVAL,
899 [RTN_UNREACHABLE] = -EHOSTUNREACH,
900 [RTN_PROHIBIT] = -EACCES,
901 [RTN_THROW] = -EAGAIN,
902 [RTN_NAT] = -EINVAL,
903 [RTN_XRESOLVE] = -EINVAL,
904 };
905
906 static int ip6_rt_type_to_error(u8 fib6_type)
907 {
908 return fib6_prop[fib6_type];
909 }
910
911 static unsigned short fib6_info_dst_flags(struct fib6_info *rt)
912 {
913 unsigned short flags = 0;
914
915 if (rt->dst_nocount)
916 flags |= DST_NOCOUNT;
917 if (rt->dst_nopolicy)
918 flags |= DST_NOPOLICY;
919 if (rt->dst_host)
920 flags |= DST_HOST;
921
922 return flags;
923 }
924
925 static void ip6_rt_init_dst_reject(struct rt6_info *rt, struct fib6_info *ort)
926 {
927 rt->dst.error = ip6_rt_type_to_error(ort->fib6_type);
928
929 switch (ort->fib6_type) {
930 case RTN_BLACKHOLE:
931 rt->dst.output = dst_discard_out;
932 rt->dst.input = dst_discard;
933 break;
934 case RTN_PROHIBIT:
935 rt->dst.output = ip6_pkt_prohibit_out;
936 rt->dst.input = ip6_pkt_prohibit;
937 break;
938 case RTN_THROW:
939 case RTN_UNREACHABLE:
940 default:
941 rt->dst.output = ip6_pkt_discard_out;
942 rt->dst.input = ip6_pkt_discard;
943 break;
944 }
945 }
946
947 static void ip6_rt_init_dst(struct rt6_info *rt, struct fib6_info *ort)
948 {
949 if (ort->fib6_flags & RTF_REJECT) {
950 ip6_rt_init_dst_reject(rt, ort);
951 return;
952 }
953
954 rt->dst.error = 0;
955 rt->dst.output = ip6_output;
956
957 if (ort->fib6_type == RTN_LOCAL || ort->fib6_type == RTN_ANYCAST) {
958 rt->dst.input = ip6_input;
959 } else if (ipv6_addr_type(&ort->fib6_dst.addr) & IPV6_ADDR_MULTICAST) {
960 rt->dst.input = ip6_mc_input;
961 } else {
962 rt->dst.input = ip6_forward;
963 }
964
965 if (ort->fib6_nh.nh_lwtstate) {
966 rt->dst.lwtstate = lwtstate_get(ort->fib6_nh.nh_lwtstate);
967 lwtunnel_set_redirect(&rt->dst);
968 }
969
970 rt->dst.lastuse = jiffies;
971 }
972
973 /* Caller must already hold reference to @from */
974 static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
975 {
976 rt->rt6i_flags &= ~RTF_EXPIRES;
977 rcu_assign_pointer(rt->from, from);
978 ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
979 }
980
981 /* Caller must already hold reference to @ort */
982 static void ip6_rt_copy_init(struct rt6_info *rt, struct fib6_info *ort)
983 {
984 struct net_device *dev = fib6_info_nh_dev(ort);
985
986 ip6_rt_init_dst(rt, ort);
987
988 rt->rt6i_dst = ort->fib6_dst;
989 rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
990 rt->rt6i_gateway = ort->fib6_nh.nh_gw;
991 rt->rt6i_flags = ort->fib6_flags;
992 rt6_set_from(rt, ort);
993 #ifdef CONFIG_IPV6_SUBTREES
994 rt->rt6i_src = ort->fib6_src;
995 #endif
996 }
997
998 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
999 struct in6_addr *saddr)
1000 {
1001 struct fib6_node *pn, *sn;
1002 while (1) {
1003 if (fn->fn_flags & RTN_TL_ROOT)
1004 return NULL;
1005 pn = rcu_dereference(fn->parent);
1006 sn = FIB6_SUBTREE(pn);
1007 if (sn && sn != fn)
1008 fn = fib6_node_lookup(sn, NULL, saddr);
1009 else
1010 fn = pn;
1011 if (fn->fn_flags & RTN_RTINFO)
1012 return fn;
1013 }
1014 }
1015
1016 static bool ip6_hold_safe(struct net *net, struct rt6_info **prt,
1017 bool null_fallback)
1018 {
1019 struct rt6_info *rt = *prt;
1020
1021 if (dst_hold_safe(&rt->dst))
1022 return true;
1023 if (null_fallback) {
1024 rt = net->ipv6.ip6_null_entry;
1025 dst_hold(&rt->dst);
1026 } else {
1027 rt = NULL;
1028 }
1029 *prt = rt;
1030 return false;
1031 }
1032
1033 /* called with rcu_lock held */
1034 static struct rt6_info *ip6_create_rt_rcu(struct fib6_info *rt)
1035 {
1036 unsigned short flags = fib6_info_dst_flags(rt);
1037 struct net_device *dev = rt->fib6_nh.nh_dev;
1038 struct rt6_info *nrt;
1039
1040 if (!fib6_info_hold_safe(rt))
1041 return NULL;
1042
1043 nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
1044 if (nrt)
1045 ip6_rt_copy_init(nrt, rt);
1046 else
1047 fib6_info_release(rt);
1048
1049 return nrt;
1050 }
1051
1052 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
1053 struct fib6_table *table,
1054 struct flowi6 *fl6,
1055 const struct sk_buff *skb,
1056 int flags)
1057 {
1058 struct fib6_info *f6i;
1059 struct fib6_node *fn;
1060 struct rt6_info *rt;
1061
1062 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1063 flags &= ~RT6_LOOKUP_F_IFACE;
1064
1065 rcu_read_lock();
1066 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1067 restart:
1068 f6i = rcu_dereference(fn->leaf);
1069 if (!f6i) {
1070 f6i = net->ipv6.fib6_null_entry;
1071 } else {
1072 f6i = rt6_device_match(net, f6i, &fl6->saddr,
1073 fl6->flowi6_oif, flags);
1074 if (f6i->fib6_nsiblings && fl6->flowi6_oif == 0)
1075 f6i = fib6_multipath_select(net, f6i, fl6,
1076 fl6->flowi6_oif, skb,
1077 flags);
1078 }
1079 if (f6i == net->ipv6.fib6_null_entry) {
1080 fn = fib6_backtrack(fn, &fl6->saddr);
1081 if (fn)
1082 goto restart;
1083 }
1084
1085 trace_fib6_table_lookup(net, f6i, table, fl6);
1086
1087 /* Search through exception table */
1088 rt = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
1089 if (rt) {
1090 if (ip6_hold_safe(net, &rt, true))
1091 dst_use_noref(&rt->dst, jiffies);
1092 } else if (f6i == net->ipv6.fib6_null_entry) {
1093 rt = net->ipv6.ip6_null_entry;
1094 dst_hold(&rt->dst);
1095 } else {
1096 rt = ip6_create_rt_rcu(f6i);
1097 if (!rt) {
1098 rt = net->ipv6.ip6_null_entry;
1099 dst_hold(&rt->dst);
1100 }
1101 }
1102
1103 rcu_read_unlock();
1104
1105 return rt;
1106 }
1107
1108 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
1109 const struct sk_buff *skb, int flags)
1110 {
1111 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup);
1112 }
1113 EXPORT_SYMBOL_GPL(ip6_route_lookup);
1114
1115 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
1116 const struct in6_addr *saddr, int oif,
1117 const struct sk_buff *skb, int strict)
1118 {
1119 struct flowi6 fl6 = {
1120 .flowi6_oif = oif,
1121 .daddr = *daddr,
1122 };
1123 struct dst_entry *dst;
1124 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
1125
1126 if (saddr) {
1127 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
1128 flags |= RT6_LOOKUP_F_HAS_SADDR;
1129 }
1130
1131 dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
1132 if (dst->error == 0)
1133 return (struct rt6_info *) dst;
1134
1135 dst_release(dst);
1136
1137 return NULL;
1138 }
1139 EXPORT_SYMBOL(rt6_lookup);
1140
1141 /* ip6_ins_rt is called with FREE table->tb6_lock.
1142 * It takes new route entry, the addition fails by any reason the
1143 * route is released.
1144 * Caller must hold dst before calling it.
1145 */
1146
1147 static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info,
1148 struct netlink_ext_ack *extack)
1149 {
1150 int err;
1151 struct fib6_table *table;
1152
1153 table = rt->fib6_table;
1154 spin_lock_bh(&table->tb6_lock);
1155 err = fib6_add(&table->tb6_root, rt, info, extack);
1156 spin_unlock_bh(&table->tb6_lock);
1157
1158 return err;
1159 }
1160
1161 int ip6_ins_rt(struct net *net, struct fib6_info *rt)
1162 {
1163 struct nl_info info = { .nl_net = net, };
1164
1165 return __ip6_ins_rt(rt, &info, NULL);
1166 }
1167
1168 static struct rt6_info *ip6_rt_cache_alloc(struct fib6_info *ort,
1169 const struct in6_addr *daddr,
1170 const struct in6_addr *saddr)
1171 {
1172 struct net_device *dev;
1173 struct rt6_info *rt;
1174
1175 /*
1176 * Clone the route.
1177 */
1178
1179 if (!fib6_info_hold_safe(ort))
1180 return NULL;
1181
1182 dev = ip6_rt_get_dev_rcu(ort);
1183 rt = ip6_dst_alloc(dev_net(dev), dev, 0);
1184 if (!rt) {
1185 fib6_info_release(ort);
1186 return NULL;
1187 }
1188
1189 ip6_rt_copy_init(rt, ort);
1190 rt->rt6i_flags |= RTF_CACHE;
1191 rt->dst.flags |= DST_HOST;
1192 rt->rt6i_dst.addr = *daddr;
1193 rt->rt6i_dst.plen = 128;
1194
1195 if (!rt6_is_gw_or_nonexthop(ort)) {
1196 if (ort->fib6_dst.plen != 128 &&
1197 ipv6_addr_equal(&ort->fib6_dst.addr, daddr))
1198 rt->rt6i_flags |= RTF_ANYCAST;
1199 #ifdef CONFIG_IPV6_SUBTREES
1200 if (rt->rt6i_src.plen && saddr) {
1201 rt->rt6i_src.addr = *saddr;
1202 rt->rt6i_src.plen = 128;
1203 }
1204 #endif
1205 }
1206
1207 return rt;
1208 }
1209
1210 static struct rt6_info *ip6_rt_pcpu_alloc(struct fib6_info *rt)
1211 {
1212 unsigned short flags = fib6_info_dst_flags(rt);
1213 struct net_device *dev;
1214 struct rt6_info *pcpu_rt;
1215
1216 if (!fib6_info_hold_safe(rt))
1217 return NULL;
1218
1219 rcu_read_lock();
1220 dev = ip6_rt_get_dev_rcu(rt);
1221 pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags);
1222 rcu_read_unlock();
1223 if (!pcpu_rt) {
1224 fib6_info_release(rt);
1225 return NULL;
1226 }
1227 ip6_rt_copy_init(pcpu_rt, rt);
1228 pcpu_rt->rt6i_flags |= RTF_PCPU;
1229 return pcpu_rt;
1230 }
1231
1232 /* It should be called with rcu_read_lock() acquired */
1233 static struct rt6_info *rt6_get_pcpu_route(struct fib6_info *rt)
1234 {
1235 struct rt6_info *pcpu_rt, **p;
1236
1237 p = this_cpu_ptr(rt->rt6i_pcpu);
1238 pcpu_rt = *p;
1239
1240 if (pcpu_rt)
1241 ip6_hold_safe(NULL, &pcpu_rt, false);
1242
1243 return pcpu_rt;
1244 }
1245
1246 static struct rt6_info *rt6_make_pcpu_route(struct net *net,
1247 struct fib6_info *rt)
1248 {
1249 struct rt6_info *pcpu_rt, *prev, **p;
1250
1251 pcpu_rt = ip6_rt_pcpu_alloc(rt);
1252 if (!pcpu_rt) {
1253 dst_hold(&net->ipv6.ip6_null_entry->dst);
1254 return net->ipv6.ip6_null_entry;
1255 }
1256
1257 dst_hold(&pcpu_rt->dst);
1258 p = this_cpu_ptr(rt->rt6i_pcpu);
1259 prev = cmpxchg(p, NULL, pcpu_rt);
1260 BUG_ON(prev);
1261
1262 return pcpu_rt;
1263 }
1264
1265 /* exception hash table implementation
1266 */
1267 static DEFINE_SPINLOCK(rt6_exception_lock);
1268
1269 /* Remove rt6_ex from hash table and free the memory
1270 * Caller must hold rt6_exception_lock
1271 */
1272 static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
1273 struct rt6_exception *rt6_ex)
1274 {
1275 struct net *net;
1276
1277 if (!bucket || !rt6_ex)
1278 return;
1279
1280 net = dev_net(rt6_ex->rt6i->dst.dev);
1281 hlist_del_rcu(&rt6_ex->hlist);
1282 dst_release(&rt6_ex->rt6i->dst);
1283 kfree_rcu(rt6_ex, rcu);
1284 WARN_ON_ONCE(!bucket->depth);
1285 bucket->depth--;
1286 net->ipv6.rt6_stats->fib_rt_cache--;
1287 }
1288
1289 /* Remove oldest rt6_ex in bucket and free the memory
1290 * Caller must hold rt6_exception_lock
1291 */
1292 static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket)
1293 {
1294 struct rt6_exception *rt6_ex, *oldest = NULL;
1295
1296 if (!bucket)
1297 return;
1298
1299 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1300 if (!oldest || time_before(rt6_ex->stamp, oldest->stamp))
1301 oldest = rt6_ex;
1302 }
1303 rt6_remove_exception(bucket, oldest);
1304 }
1305
1306 static u32 rt6_exception_hash(const struct in6_addr *dst,
1307 const struct in6_addr *src)
1308 {
1309 static u32 seed __read_mostly;
1310 u32 val;
1311
1312 net_get_random_once(&seed, sizeof(seed));
1313 val = jhash(dst, sizeof(*dst), seed);
1314
1315 #ifdef CONFIG_IPV6_SUBTREES
1316 if (src)
1317 val = jhash(src, sizeof(*src), val);
1318 #endif
1319 return hash_32(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT);
1320 }
1321
1322 /* Helper function to find the cached rt in the hash table
1323 * and update bucket pointer to point to the bucket for this
1324 * (daddr, saddr) pair
1325 * Caller must hold rt6_exception_lock
1326 */
1327 static struct rt6_exception *
1328 __rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket,
1329 const struct in6_addr *daddr,
1330 const struct in6_addr *saddr)
1331 {
1332 struct rt6_exception *rt6_ex;
1333 u32 hval;
1334
1335 if (!(*bucket) || !daddr)
1336 return NULL;
1337
1338 hval = rt6_exception_hash(daddr, saddr);
1339 *bucket += hval;
1340
1341 hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) {
1342 struct rt6_info *rt6 = rt6_ex->rt6i;
1343 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1344
1345 #ifdef CONFIG_IPV6_SUBTREES
1346 if (matched && saddr)
1347 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1348 #endif
1349 if (matched)
1350 return rt6_ex;
1351 }
1352 return NULL;
1353 }
1354
1355 /* Helper function to find the cached rt in the hash table
1356 * and update bucket pointer to point to the bucket for this
1357 * (daddr, saddr) pair
1358 * Caller must hold rcu_read_lock()
1359 */
1360 static struct rt6_exception *
1361 __rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
1362 const struct in6_addr *daddr,
1363 const struct in6_addr *saddr)
1364 {
1365 struct rt6_exception *rt6_ex;
1366 u32 hval;
1367
1368 WARN_ON_ONCE(!rcu_read_lock_held());
1369
1370 if (!(*bucket) || !daddr)
1371 return NULL;
1372
1373 hval = rt6_exception_hash(daddr, saddr);
1374 *bucket += hval;
1375
1376 hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) {
1377 struct rt6_info *rt6 = rt6_ex->rt6i;
1378 bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr);
1379
1380 #ifdef CONFIG_IPV6_SUBTREES
1381 if (matched && saddr)
1382 matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr);
1383 #endif
1384 if (matched)
1385 return rt6_ex;
1386 }
1387 return NULL;
1388 }
1389
1390 static unsigned int fib6_mtu(const struct fib6_info *rt)
1391 {
1392 unsigned int mtu;
1393
1394 if (rt->fib6_pmtu) {
1395 mtu = rt->fib6_pmtu;
1396 } else {
1397 struct net_device *dev = fib6_info_nh_dev(rt);
1398 struct inet6_dev *idev;
1399
1400 rcu_read_lock();
1401 idev = __in6_dev_get(dev);
1402 mtu = idev->cnf.mtu6;
1403 rcu_read_unlock();
1404 }
1405
1406 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1407
1408 return mtu - lwtunnel_headroom(rt->fib6_nh.nh_lwtstate, mtu);
1409 }
1410
1411 static int rt6_insert_exception(struct rt6_info *nrt,
1412 struct fib6_info *ort)
1413 {
1414 struct net *net = dev_net(nrt->dst.dev);
1415 struct rt6_exception_bucket *bucket;
1416 struct in6_addr *src_key = NULL;
1417 struct rt6_exception *rt6_ex;
1418 int err = 0;
1419
1420 spin_lock_bh(&rt6_exception_lock);
1421
1422 if (ort->exception_bucket_flushed) {
1423 err = -EINVAL;
1424 goto out;
1425 }
1426
1427 bucket = rcu_dereference_protected(ort->rt6i_exception_bucket,
1428 lockdep_is_held(&rt6_exception_lock));
1429 if (!bucket) {
1430 bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket),
1431 GFP_ATOMIC);
1432 if (!bucket) {
1433 err = -ENOMEM;
1434 goto out;
1435 }
1436 rcu_assign_pointer(ort->rt6i_exception_bucket, bucket);
1437 }
1438
1439 #ifdef CONFIG_IPV6_SUBTREES
1440 /* rt6i_src.plen != 0 indicates ort is in subtree
1441 * and exception table is indexed by a hash of
1442 * both rt6i_dst and rt6i_src.
1443 * Otherwise, the exception table is indexed by
1444 * a hash of only rt6i_dst.
1445 */
1446 if (ort->fib6_src.plen)
1447 src_key = &nrt->rt6i_src.addr;
1448 #endif
1449 /* rt6_mtu_change() might lower mtu on ort.
1450 * Only insert this exception route if its mtu
1451 * is less than ort's mtu value.
1452 */
1453 if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(ort)) {
1454 err = -EINVAL;
1455 goto out;
1456 }
1457
1458 rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr,
1459 src_key);
1460 if (rt6_ex)
1461 rt6_remove_exception(bucket, rt6_ex);
1462
1463 rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC);
1464 if (!rt6_ex) {
1465 err = -ENOMEM;
1466 goto out;
1467 }
1468 rt6_ex->rt6i = nrt;
1469 rt6_ex->stamp = jiffies;
1470 hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
1471 bucket->depth++;
1472 net->ipv6.rt6_stats->fib_rt_cache++;
1473
1474 if (bucket->depth > FIB6_MAX_DEPTH)
1475 rt6_exception_remove_oldest(bucket);
1476
1477 out:
1478 spin_unlock_bh(&rt6_exception_lock);
1479
1480 /* Update fn->fn_sernum to invalidate all cached dst */
1481 if (!err) {
1482 spin_lock_bh(&ort->fib6_table->tb6_lock);
1483 fib6_update_sernum(net, ort);
1484 spin_unlock_bh(&ort->fib6_table->tb6_lock);
1485 fib6_force_start_gc(net);
1486 }
1487
1488 return err;
1489 }
1490
1491 void rt6_flush_exceptions(struct fib6_info *rt)
1492 {
1493 struct rt6_exception_bucket *bucket;
1494 struct rt6_exception *rt6_ex;
1495 struct hlist_node *tmp;
1496 int i;
1497
1498 spin_lock_bh(&rt6_exception_lock);
1499 /* Prevent rt6_insert_exception() to recreate the bucket list */
1500 rt->exception_bucket_flushed = 1;
1501
1502 bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
1503 lockdep_is_held(&rt6_exception_lock));
1504 if (!bucket)
1505 goto out;
1506
1507 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1508 hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist)
1509 rt6_remove_exception(bucket, rt6_ex);
1510 WARN_ON_ONCE(bucket->depth);
1511 bucket++;
1512 }
1513
1514 out:
1515 spin_unlock_bh(&rt6_exception_lock);
1516 }
1517
1518 /* Find cached rt in the hash table inside passed in rt
1519 * Caller has to hold rcu_read_lock()
1520 */
1521 static struct rt6_info *rt6_find_cached_rt(struct fib6_info *rt,
1522 struct in6_addr *daddr,
1523 struct in6_addr *saddr)
1524 {
1525 struct rt6_exception_bucket *bucket;
1526 struct in6_addr *src_key = NULL;
1527 struct rt6_exception *rt6_ex;
1528 struct rt6_info *res = NULL;
1529
1530 bucket = rcu_dereference(rt->rt6i_exception_bucket);
1531
1532 #ifdef CONFIG_IPV6_SUBTREES
1533 /* rt6i_src.plen != 0 indicates rt is in subtree
1534 * and exception table is indexed by a hash of
1535 * both rt6i_dst and rt6i_src.
1536 * Otherwise, the exception table is indexed by
1537 * a hash of only rt6i_dst.
1538 */
1539 if (rt->fib6_src.plen)
1540 src_key = saddr;
1541 #endif
1542 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
1543
1544 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
1545 res = rt6_ex->rt6i;
1546
1547 return res;
1548 }
1549
1550 /* Remove the passed in cached rt from the hash table that contains it */
1551 static int rt6_remove_exception_rt(struct rt6_info *rt)
1552 {
1553 struct rt6_exception_bucket *bucket;
1554 struct in6_addr *src_key = NULL;
1555 struct rt6_exception *rt6_ex;
1556 struct fib6_info *from;
1557 int err;
1558
1559 from = rcu_dereference(rt->from);
1560 if (!from ||
1561 !(rt->rt6i_flags & RTF_CACHE))
1562 return -EINVAL;
1563
1564 if (!rcu_access_pointer(from->rt6i_exception_bucket))
1565 return -ENOENT;
1566
1567 spin_lock_bh(&rt6_exception_lock);
1568 bucket = rcu_dereference_protected(from->rt6i_exception_bucket,
1569 lockdep_is_held(&rt6_exception_lock));
1570 #ifdef CONFIG_IPV6_SUBTREES
1571 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1572 * and exception table is indexed by a hash of
1573 * both rt6i_dst and rt6i_src.
1574 * Otherwise, the exception table is indexed by
1575 * a hash of only rt6i_dst.
1576 */
1577 if (from->fib6_src.plen)
1578 src_key = &rt->rt6i_src.addr;
1579 #endif
1580 rt6_ex = __rt6_find_exception_spinlock(&bucket,
1581 &rt->rt6i_dst.addr,
1582 src_key);
1583 if (rt6_ex) {
1584 rt6_remove_exception(bucket, rt6_ex);
1585 err = 0;
1586 } else {
1587 err = -ENOENT;
1588 }
1589
1590 spin_unlock_bh(&rt6_exception_lock);
1591 return err;
1592 }
1593
1594 /* Find rt6_ex which contains the passed in rt cache and
1595 * refresh its stamp
1596 */
1597 static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
1598 {
1599 struct rt6_exception_bucket *bucket;
1600 struct fib6_info *from = rt->from;
1601 struct in6_addr *src_key = NULL;
1602 struct rt6_exception *rt6_ex;
1603
1604 if (!from ||
1605 !(rt->rt6i_flags & RTF_CACHE))
1606 return;
1607
1608 rcu_read_lock();
1609 bucket = rcu_dereference(from->rt6i_exception_bucket);
1610
1611 #ifdef CONFIG_IPV6_SUBTREES
1612 /* rt6i_src.plen != 0 indicates 'from' is in subtree
1613 * and exception table is indexed by a hash of
1614 * both rt6i_dst and rt6i_src.
1615 * Otherwise, the exception table is indexed by
1616 * a hash of only rt6i_dst.
1617 */
1618 if (from->fib6_src.plen)
1619 src_key = &rt->rt6i_src.addr;
1620 #endif
1621 rt6_ex = __rt6_find_exception_rcu(&bucket,
1622 &rt->rt6i_dst.addr,
1623 src_key);
1624 if (rt6_ex)
1625 rt6_ex->stamp = jiffies;
1626
1627 rcu_read_unlock();
1628 }
1629
1630 static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
1631 struct rt6_info *rt, int mtu)
1632 {
1633 /* If the new MTU is lower than the route PMTU, this new MTU will be the
1634 * lowest MTU in the path: always allow updating the route PMTU to
1635 * reflect PMTU decreases.
1636 *
1637 * If the new MTU is higher, and the route PMTU is equal to the local
1638 * MTU, this means the old MTU is the lowest in the path, so allow
1639 * updating it: if other nodes now have lower MTUs, PMTU discovery will
1640 * handle this.
1641 */
1642
1643 if (dst_mtu(&rt->dst) >= mtu)
1644 return true;
1645
1646 if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
1647 return true;
1648
1649 return false;
1650 }
1651
1652 static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
1653 struct fib6_info *rt, int mtu)
1654 {
1655 struct rt6_exception_bucket *bucket;
1656 struct rt6_exception *rt6_ex;
1657 int i;
1658
1659 bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
1660 lockdep_is_held(&rt6_exception_lock));
1661
1662 if (!bucket)
1663 return;
1664
1665 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1666 hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
1667 struct rt6_info *entry = rt6_ex->rt6i;
1668
1669 /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
1670 * route), the metrics of its rt->from have already
1671 * been updated.
1672 */
1673 if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
1674 rt6_mtu_change_route_allowed(idev, entry, mtu))
1675 dst_metric_set(&entry->dst, RTAX_MTU, mtu);
1676 }
1677 bucket++;
1678 }
1679 }
1680
1681 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
1682
1683 static void rt6_exceptions_clean_tohost(struct fib6_info *rt,
1684 struct in6_addr *gateway)
1685 {
1686 struct rt6_exception_bucket *bucket;
1687 struct rt6_exception *rt6_ex;
1688 struct hlist_node *tmp;
1689 int i;
1690
1691 if (!rcu_access_pointer(rt->rt6i_exception_bucket))
1692 return;
1693
1694 spin_lock_bh(&rt6_exception_lock);
1695 bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
1696 lockdep_is_held(&rt6_exception_lock));
1697
1698 if (bucket) {
1699 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1700 hlist_for_each_entry_safe(rt6_ex, tmp,
1701 &bucket->chain, hlist) {
1702 struct rt6_info *entry = rt6_ex->rt6i;
1703
1704 if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
1705 RTF_CACHE_GATEWAY &&
1706 ipv6_addr_equal(gateway,
1707 &entry->rt6i_gateway)) {
1708 rt6_remove_exception(bucket, rt6_ex);
1709 }
1710 }
1711 bucket++;
1712 }
1713 }
1714
1715 spin_unlock_bh(&rt6_exception_lock);
1716 }
1717
1718 static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
1719 struct rt6_exception *rt6_ex,
1720 struct fib6_gc_args *gc_args,
1721 unsigned long now)
1722 {
1723 struct rt6_info *rt = rt6_ex->rt6i;
1724
1725 /* we are pruning and obsoleting aged-out and non gateway exceptions
1726 * even if others have still references to them, so that on next
1727 * dst_check() such references can be dropped.
1728 * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
1729 * expired, independently from their aging, as per RFC 8201 section 4
1730 */
1731 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
1732 if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
1733 RT6_TRACE("aging clone %p\n", rt);
1734 rt6_remove_exception(bucket, rt6_ex);
1735 return;
1736 }
1737 } else if (time_after(jiffies, rt->dst.expires)) {
1738 RT6_TRACE("purging expired route %p\n", rt);
1739 rt6_remove_exception(bucket, rt6_ex);
1740 return;
1741 }
1742
1743 if (rt->rt6i_flags & RTF_GATEWAY) {
1744 struct neighbour *neigh;
1745 __u8 neigh_flags = 0;
1746
1747 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
1748 if (neigh)
1749 neigh_flags = neigh->flags;
1750
1751 if (!(neigh_flags & NTF_ROUTER)) {
1752 RT6_TRACE("purging route %p via non-router but gateway\n",
1753 rt);
1754 rt6_remove_exception(bucket, rt6_ex);
1755 return;
1756 }
1757 }
1758
1759 gc_args->more++;
1760 }
1761
1762 void rt6_age_exceptions(struct fib6_info *rt,
1763 struct fib6_gc_args *gc_args,
1764 unsigned long now)
1765 {
1766 struct rt6_exception_bucket *bucket;
1767 struct rt6_exception *rt6_ex;
1768 struct hlist_node *tmp;
1769 int i;
1770
1771 if (!rcu_access_pointer(rt->rt6i_exception_bucket))
1772 return;
1773
1774 rcu_read_lock_bh();
1775 spin_lock(&rt6_exception_lock);
1776 bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
1777 lockdep_is_held(&rt6_exception_lock));
1778
1779 if (bucket) {
1780 for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
1781 hlist_for_each_entry_safe(rt6_ex, tmp,
1782 &bucket->chain, hlist) {
1783 rt6_age_examine_exception(bucket, rt6_ex,
1784 gc_args, now);
1785 }
1786 bucket++;
1787 }
1788 }
1789 spin_unlock(&rt6_exception_lock);
1790 rcu_read_unlock_bh();
1791 }
1792
1793 /* must be called with rcu lock held */
1794 struct fib6_info *fib6_table_lookup(struct net *net, struct fib6_table *table,
1795 int oif, struct flowi6 *fl6, int strict)
1796 {
1797 struct fib6_node *fn, *saved_fn;
1798 struct fib6_info *f6i;
1799
1800 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1801 saved_fn = fn;
1802
1803 if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1804 oif = 0;
1805
1806 redo_rt6_select:
1807 f6i = rt6_select(net, fn, oif, strict);
1808 if (f6i == net->ipv6.fib6_null_entry) {
1809 fn = fib6_backtrack(fn, &fl6->saddr);
1810 if (fn)
1811 goto redo_rt6_select;
1812 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1813 /* also consider unreachable route */
1814 strict &= ~RT6_LOOKUP_F_REACHABLE;
1815 fn = saved_fn;
1816 goto redo_rt6_select;
1817 }
1818 }
1819
1820 trace_fib6_table_lookup(net, f6i, table, fl6);
1821
1822 return f6i;
1823 }
1824
1825 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
1826 int oif, struct flowi6 *fl6,
1827 const struct sk_buff *skb, int flags)
1828 {
1829 struct fib6_info *f6i;
1830 struct rt6_info *rt;
1831 int strict = 0;
1832
1833 strict |= flags & RT6_LOOKUP_F_IFACE;
1834 strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
1835 if (net->ipv6.devconf_all->forwarding == 0)
1836 strict |= RT6_LOOKUP_F_REACHABLE;
1837
1838 rcu_read_lock();
1839
1840 f6i = fib6_table_lookup(net, table, oif, fl6, strict);
1841 if (f6i->fib6_nsiblings)
1842 f6i = fib6_multipath_select(net, f6i, fl6, oif, skb, strict);
1843
1844 if (f6i == net->ipv6.fib6_null_entry) {
1845 rt = net->ipv6.ip6_null_entry;
1846 rcu_read_unlock();
1847 dst_hold(&rt->dst);
1848 return rt;
1849 }
1850
1851 /*Search through exception table */
1852 rt = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
1853 if (rt) {
1854 if (ip6_hold_safe(net, &rt, true))
1855 dst_use_noref(&rt->dst, jiffies);
1856
1857 rcu_read_unlock();
1858 return rt;
1859 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1860 !(f6i->fib6_flags & RTF_GATEWAY))) {
1861 /* Create a RTF_CACHE clone which will not be
1862 * owned by the fib6 tree. It is for the special case where
1863 * the daddr in the skb during the neighbor look-up is different
1864 * from the fl6->daddr used to look-up route here.
1865 */
1866 struct rt6_info *uncached_rt;
1867
1868 uncached_rt = ip6_rt_cache_alloc(f6i, &fl6->daddr, NULL);
1869
1870 rcu_read_unlock();
1871
1872 if (uncached_rt) {
1873 /* Uncached_rt's refcnt is taken during ip6_rt_cache_alloc()
1874 * No need for another dst_hold()
1875 */
1876 rt6_uncached_list_add(uncached_rt);
1877 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
1878 } else {
1879 uncached_rt = net->ipv6.ip6_null_entry;
1880 dst_hold(&uncached_rt->dst);
1881 }
1882
1883 return uncached_rt;
1884 } else {
1885 /* Get a percpu copy */
1886
1887 struct rt6_info *pcpu_rt;
1888
1889 local_bh_disable();
1890 pcpu_rt = rt6_get_pcpu_route(f6i);
1891
1892 if (!pcpu_rt)
1893 pcpu_rt = rt6_make_pcpu_route(net, f6i);
1894
1895 local_bh_enable();
1896 rcu_read_unlock();
1897
1898 return pcpu_rt;
1899 }
1900 }
1901 EXPORT_SYMBOL_GPL(ip6_pol_route);
1902
1903 static struct rt6_info *ip6_pol_route_input(struct net *net,
1904 struct fib6_table *table,
1905 struct flowi6 *fl6,
1906 const struct sk_buff *skb,
1907 int flags)
1908 {
1909 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags);
1910 }
1911
1912 struct dst_entry *ip6_route_input_lookup(struct net *net,
1913 struct net_device *dev,
1914 struct flowi6 *fl6,
1915 const struct sk_buff *skb,
1916 int flags)
1917 {
1918 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1919 flags |= RT6_LOOKUP_F_IFACE;
1920
1921 return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input);
1922 }
1923 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
1924
1925 static void ip6_multipath_l3_keys(const struct sk_buff *skb,
1926 struct flow_keys *keys,
1927 struct flow_keys *flkeys)
1928 {
1929 const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
1930 const struct ipv6hdr *key_iph = outer_iph;
1931 struct flow_keys *_flkeys = flkeys;
1932 const struct ipv6hdr *inner_iph;
1933 const struct icmp6hdr *icmph;
1934 struct ipv6hdr _inner_iph;
1935 struct icmp6hdr _icmph;
1936
1937 if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6))
1938 goto out;
1939
1940 icmph = skb_header_pointer(skb, skb_transport_offset(skb),
1941 sizeof(_icmph), &_icmph);
1942 if (!icmph)
1943 goto out;
1944
1945 if (icmph->icmp6_type != ICMPV6_DEST_UNREACH &&
1946 icmph->icmp6_type != ICMPV6_PKT_TOOBIG &&
1947 icmph->icmp6_type != ICMPV6_TIME_EXCEED &&
1948 icmph->icmp6_type != ICMPV6_PARAMPROB)
1949 goto out;
1950
1951 inner_iph = skb_header_pointer(skb,
1952 skb_transport_offset(skb) + sizeof(*icmph),
1953 sizeof(_inner_iph), &_inner_iph);
1954 if (!inner_iph)
1955 goto out;
1956
1957 key_iph = inner_iph;
1958 _flkeys = NULL;
1959 out:
1960 if (_flkeys) {
1961 keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src;
1962 keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst;
1963 keys->tags.flow_label = _flkeys->tags.flow_label;
1964 keys->basic.ip_proto = _flkeys->basic.ip_proto;
1965 } else {
1966 keys->addrs.v6addrs.src = key_iph->saddr;
1967 keys->addrs.v6addrs.dst = key_iph->daddr;
1968 keys->tags.flow_label = ip6_flowlabel(key_iph);
1969 keys->basic.ip_proto = key_iph->nexthdr;
1970 }
1971 }
1972
1973 /* if skb is set it will be used and fl6 can be NULL */
1974 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
1975 const struct sk_buff *skb, struct flow_keys *flkeys)
1976 {
1977 struct flow_keys hash_keys;
1978 u32 mhash;
1979
1980 switch (ip6_multipath_hash_policy(net)) {
1981 case 0:
1982 memset(&hash_keys, 0, sizeof(hash_keys));
1983 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1984 if (skb) {
1985 ip6_multipath_l3_keys(skb, &hash_keys, flkeys);
1986 } else {
1987 hash_keys.addrs.v6addrs.src = fl6->saddr;
1988 hash_keys.addrs.v6addrs.dst = fl6->daddr;
1989 hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1990 hash_keys.basic.ip_proto = fl6->flowi6_proto;
1991 }
1992 break;
1993 case 1:
1994 if (skb) {
1995 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
1996 struct flow_keys keys;
1997
1998 /* short-circuit if we already have L4 hash present */
1999 if (skb->l4_hash)
2000 return skb_get_hash_raw(skb) >> 1;
2001
2002 memset(&hash_keys, 0, sizeof(hash_keys));
2003
2004 if (!flkeys) {
2005 skb_flow_dissect_flow_keys(skb, &keys, flag);
2006 flkeys = &keys;
2007 }
2008 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2009 hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src;
2010 hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst;
2011 hash_keys.ports.src = flkeys->ports.src;
2012 hash_keys.ports.dst = flkeys->ports.dst;
2013 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
2014 } else {
2015 memset(&hash_keys, 0, sizeof(hash_keys));
2016 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
2017 hash_keys.addrs.v6addrs.src = fl6->saddr;
2018 hash_keys.addrs.v6addrs.dst = fl6->daddr;
2019 hash_keys.ports.src = fl6->fl6_sport;
2020 hash_keys.ports.dst = fl6->fl6_dport;
2021 hash_keys.basic.ip_proto = fl6->flowi6_proto;
2022 }
2023 break;
2024 }
2025 mhash = flow_hash_from_keys(&hash_keys);
2026
2027 return mhash >> 1;
2028 }
2029
2030 void ip6_route_input(struct sk_buff *skb)
2031 {
2032 const struct ipv6hdr *iph = ipv6_hdr(skb);
2033 struct net *net = dev_net(skb->dev);
2034 int flags = RT6_LOOKUP_F_HAS_SADDR;
2035 struct ip_tunnel_info *tun_info;
2036 struct flowi6 fl6 = {
2037 .flowi6_iif = skb->dev->ifindex,
2038 .daddr = iph->daddr,
2039 .saddr = iph->saddr,
2040 .flowlabel = ip6_flowinfo(iph),
2041 .flowi6_mark = skb->mark,
2042 .flowi6_proto = iph->nexthdr,
2043 };
2044 struct flow_keys *flkeys = NULL, _flkeys;
2045
2046 tun_info = skb_tunnel_info(skb);
2047 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
2048 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
2049
2050 if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys))
2051 flkeys = &_flkeys;
2052
2053 if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6))
2054 fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys);
2055 skb_dst_drop(skb);
2056 skb_dst_set(skb,
2057 ip6_route_input_lookup(net, skb->dev, &fl6, skb, flags));
2058 }
2059
2060 static struct rt6_info *ip6_pol_route_output(struct net *net,
2061 struct fib6_table *table,
2062 struct flowi6 *fl6,
2063 const struct sk_buff *skb,
2064 int flags)
2065 {
2066 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags);
2067 }
2068
2069 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
2070 struct flowi6 *fl6, int flags)
2071 {
2072 bool any_src;
2073
2074 if (ipv6_addr_type(&fl6->daddr) &
2075 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
2076 struct dst_entry *dst;
2077
2078 dst = l3mdev_link_scope_lookup(net, fl6);
2079 if (dst)
2080 return dst;
2081 }
2082
2083 fl6->flowi6_iif = LOOPBACK_IFINDEX;
2084
2085 any_src = ipv6_addr_any(&fl6->saddr);
2086 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
2087 (fl6->flowi6_oif && any_src))
2088 flags |= RT6_LOOKUP_F_IFACE;
2089
2090 if (!any_src)
2091 flags |= RT6_LOOKUP_F_HAS_SADDR;
2092 else if (sk)
2093 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
2094
2095 return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
2096 }
2097 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
2098
2099 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2100 {
2101 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
2102 struct net_device *loopback_dev = net->loopback_dev;
2103 struct dst_entry *new = NULL;
2104
2105 rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, 1,
2106 DST_OBSOLETE_DEAD, 0);
2107 if (rt) {
2108 rt6_info_init(rt);
2109 atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
2110
2111 new = &rt->dst;
2112 new->__use = 1;
2113 new->input = dst_discard;
2114 new->output = dst_discard_out;
2115
2116 dst_copy_metrics(new, &ort->dst);
2117
2118 rt->rt6i_idev = in6_dev_get(loopback_dev);
2119 rt->rt6i_gateway = ort->rt6i_gateway;
2120 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
2121
2122 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
2123 #ifdef CONFIG_IPV6_SUBTREES
2124 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
2125 #endif
2126 }
2127
2128 dst_release(dst_orig);
2129 return new ? new : ERR_PTR(-ENOMEM);
2130 }
2131
2132 /*
2133 * Destination cache support functions
2134 */
2135
2136 static bool fib6_check(struct fib6_info *f6i, u32 cookie)
2137 {
2138 u32 rt_cookie = 0;
2139
2140 if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
2141 return false;
2142
2143 if (fib6_check_expired(f6i))
2144 return false;
2145
2146 return true;
2147 }
2148
2149 static struct dst_entry *rt6_check(struct rt6_info *rt,
2150 struct fib6_info *from,
2151 u32 cookie)
2152 {
2153 u32 rt_cookie = 0;
2154
2155 if ((from && !fib6_get_cookie_safe(from, &rt_cookie)) ||
2156 rt_cookie != cookie)
2157 return NULL;
2158
2159 if (rt6_check_expired(rt))
2160 return NULL;
2161
2162 return &rt->dst;
2163 }
2164
2165 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
2166 struct fib6_info *from,
2167 u32 cookie)
2168 {
2169 if (!__rt6_check_expired(rt) &&
2170 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
2171 fib6_check(from, cookie))
2172 return &rt->dst;
2173 else
2174 return NULL;
2175 }
2176
2177 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
2178 {
2179 struct dst_entry *dst_ret;
2180 struct fib6_info *from;
2181 struct rt6_info *rt;
2182
2183 rt = container_of(dst, struct rt6_info, dst);
2184
2185 rcu_read_lock();
2186
2187 /* All IPV6 dsts are created with ->obsolete set to the value
2188 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
2189 * into this function always.
2190 */
2191
2192 from = rcu_dereference(rt->from);
2193
2194 if (from && (rt->rt6i_flags & RTF_PCPU ||
2195 unlikely(!list_empty(&rt->rt6i_uncached))))
2196 dst_ret = rt6_dst_from_check(rt, from, cookie);
2197 else
2198 dst_ret = rt6_check(rt, from, cookie);
2199
2200 rcu_read_unlock();
2201
2202 return dst_ret;
2203 }
2204
2205 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
2206 {
2207 struct rt6_info *rt = (struct rt6_info *) dst;
2208
2209 if (rt) {
2210 if (rt->rt6i_flags & RTF_CACHE) {
2211 rcu_read_lock();
2212 if (rt6_check_expired(rt)) {
2213 rt6_remove_exception_rt(rt);
2214 dst = NULL;
2215 }
2216 rcu_read_unlock();
2217 } else {
2218 dst_release(dst);
2219 dst = NULL;
2220 }
2221 }
2222 return dst;
2223 }
2224
2225 static void ip6_link_failure(struct sk_buff *skb)
2226 {
2227 struct rt6_info *rt;
2228
2229 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
2230
2231 rt = (struct rt6_info *) skb_dst(skb);
2232 if (rt) {
2233 rcu_read_lock();
2234 if (rt->rt6i_flags & RTF_CACHE) {
2235 rt6_remove_exception_rt(rt);
2236 } else {
2237 struct fib6_info *from;
2238 struct fib6_node *fn;
2239
2240 from = rcu_dereference(rt->from);
2241 if (from) {
2242 fn = rcu_dereference(from->fib6_node);
2243 if (fn && (rt->rt6i_flags & RTF_DEFAULT))
2244 fn->fn_sernum = -1;
2245 }
2246 }
2247 rcu_read_unlock();
2248 }
2249 }
2250
2251 static void rt6_update_expires(struct rt6_info *rt0, int timeout)
2252 {
2253 if (!(rt0->rt6i_flags & RTF_EXPIRES)) {
2254 struct fib6_info *from;
2255
2256 rcu_read_lock();
2257 from = rcu_dereference(rt0->from);
2258 if (from)
2259 rt0->dst.expires = from->expires;
2260 rcu_read_unlock();
2261 }
2262
2263 dst_set_expires(&rt0->dst, timeout);
2264 rt0->rt6i_flags |= RTF_EXPIRES;
2265 }
2266
2267 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
2268 {
2269 struct net *net = dev_net(rt->dst.dev);
2270
2271 dst_metric_set(&rt->dst, RTAX_MTU, mtu);
2272 rt->rt6i_flags |= RTF_MODIFIED;
2273 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
2274 }
2275
2276 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
2277 {
2278 bool from_set;
2279
2280 rcu_read_lock();
2281 from_set = !!rcu_dereference(rt->from);
2282 rcu_read_unlock();
2283
2284 return !(rt->rt6i_flags & RTF_CACHE) &&
2285 (rt->rt6i_flags & RTF_PCPU || from_set);
2286 }
2287
2288 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
2289 const struct ipv6hdr *iph, u32 mtu)
2290 {
2291 const struct in6_addr *daddr, *saddr;
2292 struct rt6_info *rt6 = (struct rt6_info *)dst;
2293
2294 if (dst_metric_locked(dst, RTAX_MTU))
2295 return;
2296
2297 if (iph) {
2298 daddr = &iph->daddr;
2299 saddr = &iph->saddr;
2300 } else if (sk) {
2301 daddr = &sk->sk_v6_daddr;
2302 saddr = &inet6_sk(sk)->saddr;
2303 } else {
2304 daddr = NULL;
2305 saddr = NULL;
2306 }
2307 dst_confirm_neigh(dst, daddr);
2308 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
2309 if (mtu >= dst_mtu(dst))
2310 return;
2311
2312 if (!rt6_cache_allowed_for_pmtu(rt6)) {
2313 rt6_do_update_pmtu(rt6, mtu);
2314 /* update rt6_ex->stamp for cache */
2315 if (rt6->rt6i_flags & RTF_CACHE)
2316 rt6_update_exception_stamp_rt(rt6);
2317 } else if (daddr) {
2318 struct fib6_info *from;
2319 struct rt6_info *nrt6;
2320
2321 rcu_read_lock();
2322 from = rcu_dereference(rt6->from);
2323 nrt6 = ip6_rt_cache_alloc(from, daddr, saddr);
2324 if (nrt6) {
2325 rt6_do_update_pmtu(nrt6, mtu);
2326 if (rt6_insert_exception(nrt6, from))
2327 dst_release_immediate(&nrt6->dst);
2328 }
2329 rcu_read_unlock();
2330 }
2331 }
2332
2333 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
2334 struct sk_buff *skb, u32 mtu)
2335 {
2336 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
2337 }
2338
2339 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
2340 int oif, u32 mark, kuid_t uid)
2341 {
2342 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2343 struct dst_entry *dst;
2344 struct flowi6 fl6 = {
2345 .flowi6_oif = oif,
2346 .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark),
2347 .daddr = iph->daddr,
2348 .saddr = iph->saddr,
2349 .flowlabel = ip6_flowinfo(iph),
2350 .flowi6_uid = uid,
2351 };
2352
2353 dst = ip6_route_output(net, NULL, &fl6);
2354 if (!dst->error)
2355 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
2356 dst_release(dst);
2357 }
2358 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
2359
2360 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
2361 {
2362 int oif = sk->sk_bound_dev_if;
2363 struct dst_entry *dst;
2364
2365 if (!oif && skb->dev)
2366 oif = l3mdev_master_ifindex(skb->dev);
2367
2368 ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
2369
2370 dst = __sk_dst_get(sk);
2371 if (!dst || !dst->obsolete ||
2372 dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
2373 return;
2374
2375 bh_lock_sock(sk);
2376 if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
2377 ip6_datagram_dst_update(sk, false);
2378 bh_unlock_sock(sk);
2379 }
2380 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
2381
2382 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
2383 const struct flowi6 *fl6)
2384 {
2385 #ifdef CONFIG_IPV6_SUBTREES
2386 struct ipv6_pinfo *np = inet6_sk(sk);
2387 #endif
2388
2389 ip6_dst_store(sk, dst,
2390 ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr) ?
2391 &sk->sk_v6_daddr : NULL,
2392 #ifdef CONFIG_IPV6_SUBTREES
2393 ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
2394 &np->saddr :
2395 #endif
2396 NULL);
2397 }
2398
2399 /* Handle redirects */
2400 struct ip6rd_flowi {
2401 struct flowi6 fl6;
2402 struct in6_addr gateway;
2403 };
2404
2405 static struct rt6_info *__ip6_route_redirect(struct net *net,
2406 struct fib6_table *table,
2407 struct flowi6 *fl6,
2408 const struct sk_buff *skb,
2409 int flags)
2410 {
2411 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
2412 struct rt6_info *ret = NULL, *rt_cache;
2413 struct fib6_info *rt;
2414 struct fib6_node *fn;
2415
2416 /* Get the "current" route for this destination and
2417 * check if the redirect has come from appropriate router.
2418 *
2419 * RFC 4861 specifies that redirects should only be
2420 * accepted if they come from the nexthop to the target.
2421 * Due to the way the routes are chosen, this notion
2422 * is a bit fuzzy and one might need to check all possible
2423 * routes.
2424 */
2425
2426 rcu_read_lock();
2427 fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
2428 restart:
2429 for_each_fib6_node_rt_rcu(fn) {
2430 if (rt->fib6_nh.nh_flags & RTNH_F_DEAD)
2431 continue;
2432 if (fib6_check_expired(rt))
2433 continue;
2434 if (rt->fib6_flags & RTF_REJECT)
2435 break;
2436 if (!(rt->fib6_flags & RTF_GATEWAY))
2437 continue;
2438 if (fl6->flowi6_oif != rt->fib6_nh.nh_dev->ifindex)
2439 continue;
2440 /* rt_cache's gateway might be different from its 'parent'
2441 * in the case of an ip redirect.
2442 * So we keep searching in the exception table if the gateway
2443 * is different.
2444 */
2445 if (!ipv6_addr_equal(&rdfl->gateway, &rt->fib6_nh.nh_gw)) {
2446 rt_cache = rt6_find_cached_rt(rt,
2447 &fl6->daddr,
2448 &fl6->saddr);
2449 if (rt_cache &&
2450 ipv6_addr_equal(&rdfl->gateway,
2451 &rt_cache->rt6i_gateway)) {
2452 ret = rt_cache;
2453 break;
2454 }
2455 continue;
2456 }
2457 break;
2458 }
2459
2460 if (!rt)
2461 rt = net->ipv6.fib6_null_entry;
2462 else if (rt->fib6_flags & RTF_REJECT) {
2463 ret = net->ipv6.ip6_null_entry;
2464 goto out;
2465 }
2466
2467 if (rt == net->ipv6.fib6_null_entry) {
2468 fn = fib6_backtrack(fn, &fl6->saddr);
2469 if (fn)
2470 goto restart;
2471 }
2472
2473 out:
2474 if (ret)
2475 ip6_hold_safe(net, &ret, true);
2476 else
2477 ret = ip6_create_rt_rcu(rt);
2478
2479 rcu_read_unlock();
2480
2481 trace_fib6_table_lookup(net, rt, table, fl6);
2482 return ret;
2483 };
2484
2485 static struct dst_entry *ip6_route_redirect(struct net *net,
2486 const struct flowi6 *fl6,
2487 const struct sk_buff *skb,
2488 const struct in6_addr *gateway)
2489 {
2490 int flags = RT6_LOOKUP_F_HAS_SADDR;
2491 struct ip6rd_flowi rdfl;
2492
2493 rdfl.fl6 = *fl6;
2494 rdfl.gateway = *gateway;
2495
2496 return fib6_rule_lookup(net, &rdfl.fl6, skb,
2497 flags, __ip6_route_redirect);
2498 }
2499
2500 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
2501 kuid_t uid)
2502 {
2503 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
2504 struct dst_entry *dst;
2505 struct flowi6 fl6 = {
2506 .flowi6_iif = LOOPBACK_IFINDEX,
2507 .flowi6_oif = oif,
2508 .flowi6_mark = mark,
2509 .daddr = iph->daddr,
2510 .saddr = iph->saddr,
2511 .flowlabel = ip6_flowinfo(iph),
2512 .flowi6_uid = uid,
2513 };
2514
2515 dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
2516 rt6_do_redirect(dst, NULL, skb);
2517 dst_release(dst);
2518 }
2519 EXPORT_SYMBOL_GPL(ip6_redirect);
2520
2521 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
2522 {
2523 const struct ipv6hdr *iph = ipv6_hdr(skb);
2524 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
2525 struct dst_entry *dst;
2526 struct flowi6 fl6 = {
2527 .flowi6_iif = LOOPBACK_IFINDEX,
2528 .flowi6_oif = oif,
2529 .daddr = msg->dest,
2530 .saddr = iph->daddr,
2531 .flowi6_uid = sock_net_uid(net, NULL),
2532 };
2533
2534 dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
2535 rt6_do_redirect(dst, NULL, skb);
2536 dst_release(dst);
2537 }
2538
2539 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
2540 {
2541 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
2542 sk->sk_uid);
2543 }
2544 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
2545
2546 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
2547 {
2548 struct net_device *dev = dst->dev;
2549 unsigned int mtu = dst_mtu(dst);
2550 struct net *net = dev_net(dev);
2551
2552 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
2553
2554 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
2555 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
2556
2557 /*
2558 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
2559 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
2560 * IPV6_MAXPLEN is also valid and means: "any MSS,
2561 * rely only on pmtu discovery"
2562 */
2563 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
2564 mtu = IPV6_MAXPLEN;
2565 return mtu;
2566 }
2567
2568 static unsigned int ip6_mtu(const struct dst_entry *dst)
2569 {
2570 struct inet6_dev *idev;
2571 unsigned int mtu;
2572
2573 mtu = dst_metric_raw(dst, RTAX_MTU);
2574 if (mtu)
2575 goto out;
2576
2577 mtu = IPV6_MIN_MTU;
2578
2579 rcu_read_lock();
2580 idev = __in6_dev_get(dst->dev);
2581 if (idev)
2582 mtu = idev->cnf.mtu6;
2583 rcu_read_unlock();
2584
2585 out:
2586 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
2587
2588 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
2589 }
2590
2591 /* MTU selection:
2592 * 1. mtu on route is locked - use it
2593 * 2. mtu from nexthop exception
2594 * 3. mtu from egress device
2595 *
2596 * based on ip6_dst_mtu_forward and exception logic of
2597 * rt6_find_cached_rt; called with rcu_read_lock
2598 */
2599 u32 ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr,
2600 struct in6_addr *saddr)
2601 {
2602 struct rt6_exception_bucket *bucket;
2603 struct rt6_exception *rt6_ex;
2604 struct in6_addr *src_key;
2605 struct inet6_dev *idev;
2606 u32 mtu = 0;
2607
2608 if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
2609 mtu = f6i->fib6_pmtu;
2610 if (mtu)
2611 goto out;
2612 }
2613
2614 src_key = NULL;
2615 #ifdef CONFIG_IPV6_SUBTREES
2616 if (f6i->fib6_src.plen)
2617 src_key = saddr;
2618 #endif
2619
2620 bucket = rcu_dereference(f6i->rt6i_exception_bucket);
2621 rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
2622 if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
2623 mtu = dst_metric_raw(&rt6_ex->rt6i->dst, RTAX_MTU);
2624
2625 if (likely(!mtu)) {
2626 struct net_device *dev = fib6_info_nh_dev(f6i);
2627
2628 mtu = IPV6_MIN_MTU;
2629 idev = __in6_dev_get(dev);
2630 if (idev && idev->cnf.mtu6 > mtu)
2631 mtu = idev->cnf.mtu6;
2632 }
2633
2634 mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
2635 out:
2636 return mtu - lwtunnel_headroom(fib6_info_nh_lwt(f6i), mtu);
2637 }
2638
2639 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
2640 struct flowi6 *fl6)
2641 {
2642 struct dst_entry *dst;
2643 struct rt6_info *rt;
2644 struct inet6_dev *idev = in6_dev_get(dev);
2645 struct net *net = dev_net(dev);
2646
2647 if (unlikely(!idev))
2648 return ERR_PTR(-ENODEV);
2649
2650 rt = ip6_dst_alloc(net, dev, 0);
2651 if (unlikely(!rt)) {
2652 in6_dev_put(idev);
2653 dst = ERR_PTR(-ENOMEM);
2654 goto out;
2655 }
2656
2657 rt->dst.flags |= DST_HOST;
2658 rt->dst.input = ip6_input;
2659 rt->dst.output = ip6_output;
2660 rt->rt6i_gateway = fl6->daddr;
2661 rt->rt6i_dst.addr = fl6->daddr;
2662 rt->rt6i_dst.plen = 128;
2663 rt->rt6i_idev = idev;
2664 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
2665
2666 /* Add this dst into uncached_list so that rt6_disable_ip() can
2667 * do proper release of the net_device
2668 */
2669 rt6_uncached_list_add(rt);
2670 atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
2671
2672 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
2673
2674 out:
2675 return dst;
2676 }
2677
2678 static int ip6_dst_gc(struct dst_ops *ops)
2679 {
2680 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
2681 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
2682 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
2683 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
2684 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
2685 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
2686 int entries;
2687
2688 entries = dst_entries_get_fast(ops);
2689 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
2690 entries <= rt_max_size)
2691 goto out;
2692
2693 net->ipv6.ip6_rt_gc_expire++;
2694 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
2695 entries = dst_entries_get_slow(ops);
2696 if (entries < ops->gc_thresh)
2697 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
2698 out:
2699 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
2700 return entries > rt_max_size;
2701 }
2702
2703 static struct rt6_info *ip6_nh_lookup_table(struct net *net,
2704 struct fib6_config *cfg,
2705 const struct in6_addr *gw_addr,
2706 u32 tbid, int flags)
2707 {
2708 struct flowi6 fl6 = {
2709 .flowi6_oif = cfg->fc_ifindex,
2710 .daddr = *gw_addr,
2711 .saddr = cfg->fc_prefsrc,
2712 };
2713 struct fib6_table *table;
2714 struct rt6_info *rt;
2715
2716 table = fib6_get_table(net, tbid);
2717 if (!table)
2718 return NULL;
2719
2720 if (!ipv6_addr_any(&cfg->fc_prefsrc))
2721 flags |= RT6_LOOKUP_F_HAS_SADDR;
2722
2723 flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
2724 rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, NULL, flags);
2725
2726 /* if table lookup failed, fall back to full lookup */
2727 if (rt == net->ipv6.ip6_null_entry) {
2728 ip6_rt_put(rt);
2729 rt = NULL;
2730 }
2731
2732 return rt;
2733 }
2734
2735 static int ip6_route_check_nh_onlink(struct net *net,
2736 struct fib6_config *cfg,
2737 const struct net_device *dev,
2738 struct netlink_ext_ack *extack)
2739 {
2740 u32 tbid = l3mdev_fib_table(dev) ? : RT_TABLE_MAIN;
2741 const struct in6_addr *gw_addr = &cfg->fc_gateway;
2742 u32 flags = RTF_LOCAL | RTF_ANYCAST | RTF_REJECT;
2743 struct rt6_info *grt;
2744 int err;
2745
2746 err = 0;
2747 grt = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0);
2748 if (grt) {
2749 if (!grt->dst.error &&
2750 /* ignore match if it is the default route */
2751 grt->from && !ipv6_addr_any(&grt->from->fib6_dst.addr) &&
2752 (grt->rt6i_flags & flags || dev != grt->dst.dev)) {
2753 NL_SET_ERR_MSG(extack,
2754 "Nexthop has invalid gateway or device mismatch");
2755 err = -EINVAL;
2756 }
2757
2758 ip6_rt_put(grt);
2759 }
2760
2761 return err;
2762 }
2763
2764 static int ip6_route_check_nh(struct net *net,
2765 struct fib6_config *cfg,
2766 struct net_device **_dev,
2767 struct inet6_dev **idev)
2768 {
2769 const struct in6_addr *gw_addr = &cfg->fc_gateway;
2770 struct net_device *dev = _dev ? *_dev : NULL;
2771 struct rt6_info *grt = NULL;
2772 int err = -EHOSTUNREACH;
2773
2774 if (cfg->fc_table) {
2775 int flags = RT6_LOOKUP_F_IFACE;
2776
2777 grt = ip6_nh_lookup_table(net, cfg, gw_addr,
2778 cfg->fc_table, flags);
2779 if (grt) {
2780 if (grt->rt6i_flags & RTF_GATEWAY ||
2781 (dev && dev != grt->dst.dev)) {
2782 ip6_rt_put(grt);
2783 grt = NULL;
2784 }
2785 }
2786 }
2787
2788 if (!grt)
2789 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, NULL, 1);
2790
2791 if (!grt)
2792 goto out;
2793
2794 if (dev) {
2795 if (dev != grt->dst.dev) {
2796 ip6_rt_put(grt);
2797 goto out;
2798 }
2799 } else {
2800 *_dev = dev = grt->dst.dev;
2801 *idev = grt->rt6i_idev;
2802 dev_hold(dev);
2803 in6_dev_hold(grt->rt6i_idev);
2804 }
2805
2806 if (!(grt->rt6i_flags & RTF_GATEWAY))
2807 err = 0;
2808
2809 ip6_rt_put(grt);
2810
2811 out:
2812 return err;
2813 }
2814
2815 static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
2816 struct net_device **_dev, struct inet6_dev **idev,
2817 struct netlink_ext_ack *extack)
2818 {
2819 const struct in6_addr *gw_addr = &cfg->fc_gateway;
2820 int gwa_type = ipv6_addr_type(gw_addr);
2821 bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
2822 const struct net_device *dev = *_dev;
2823 bool need_addr_check = !dev;
2824 int err = -EINVAL;
2825
2826 /* if gw_addr is local we will fail to detect this in case
2827 * address is still TENTATIVE (DAD in progress). rt6_lookup()
2828 * will return already-added prefix route via interface that
2829 * prefix route was assigned to, which might be non-loopback.
2830 */
2831 if (dev &&
2832 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
2833 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
2834 goto out;
2835 }
2836
2837 if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
2838 /* IPv6 strictly inhibits using not link-local
2839 * addresses as nexthop address.
2840 * Otherwise, router will not able to send redirects.
2841 * It is very good, but in some (rare!) circumstances
2842 * (SIT, PtP, NBMA NOARP links) it is handy to allow
2843 * some exceptions. --ANK
2844 * We allow IPv4-mapped nexthops to support RFC4798-type
2845 * addressing
2846 */
2847 if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
2848 NL_SET_ERR_MSG(extack, "Invalid gateway address");
2849 goto out;
2850 }
2851
2852 if (cfg->fc_flags & RTNH_F_ONLINK)
2853 err = ip6_route_check_nh_onlink(net, cfg, dev, extack);
2854 else
2855 err = ip6_route_check_nh(net, cfg, _dev, idev);
2856
2857 if (err)
2858 goto out;
2859 }
2860
2861 /* reload in case device was changed */
2862 dev = *_dev;
2863
2864 err = -EINVAL;
2865 if (!dev) {
2866 NL_SET_ERR_MSG(extack, "Egress device not specified");
2867 goto out;
2868 } else if (dev->flags & IFF_LOOPBACK) {
2869 NL_SET_ERR_MSG(extack,
2870 "Egress device can not be loopback device for this route");
2871 goto out;
2872 }
2873
2874 /* if we did not check gw_addr above, do so now that the
2875 * egress device has been resolved.
2876 */
2877 if (need_addr_check &&
2878 ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
2879 NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
2880 goto out;
2881 }
2882
2883 err = 0;
2884 out:
2885 return err;
2886 }
2887
2888 static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
2889 gfp_t gfp_flags,
2890 struct netlink_ext_ack *extack)
2891 {
2892 struct net *net = cfg->fc_nlinfo.nl_net;
2893 struct fib6_info *rt = NULL;
2894 struct net_device *dev = NULL;
2895 struct inet6_dev *idev = NULL;
2896 struct fib6_table *table;
2897 int addr_type;
2898 int err = -EINVAL;
2899
2900 /* RTF_PCPU is an internal flag; can not be set by userspace */
2901 if (cfg->fc_flags & RTF_PCPU) {
2902 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
2903 goto out;
2904 }
2905
2906 /* RTF_CACHE is an internal flag; can not be set by userspace */
2907 if (cfg->fc_flags & RTF_CACHE) {
2908 NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE");
2909 goto out;
2910 }
2911
2912 if (cfg->fc_type > RTN_MAX) {
2913 NL_SET_ERR_MSG(extack, "Invalid route type");
2914 goto out;
2915 }
2916
2917 if (cfg->fc_dst_len > 128) {
2918 NL_SET_ERR_MSG(extack, "Invalid prefix length");
2919 goto out;
2920 }
2921 if (cfg->fc_src_len > 128) {
2922 NL_SET_ERR_MSG(extack, "Invalid source address length");
2923 goto out;
2924 }
2925 #ifndef CONFIG_IPV6_SUBTREES
2926 if (cfg->fc_src_len) {
2927 NL_SET_ERR_MSG(extack,
2928 "Specifying source address requires IPV6_SUBTREES to be enabled");
2929 goto out;
2930 }
2931 #endif
2932 if (cfg->fc_ifindex) {
2933 err = -ENODEV;
2934 dev = dev_get_by_index(net, cfg->fc_ifindex);
2935 if (!dev)
2936 goto out;
2937 idev = in6_dev_get(dev);
2938 if (!idev)
2939 goto out;
2940 }
2941
2942 if (cfg->fc_metric == 0)
2943 cfg->fc_metric = IP6_RT_PRIO_USER;
2944
2945 if (cfg->fc_flags & RTNH_F_ONLINK) {
2946 if (!dev) {
2947 NL_SET_ERR_MSG(extack,
2948 "Nexthop device required for onlink");
2949 err = -ENODEV;
2950 goto out;
2951 }
2952
2953 if (!(dev->flags & IFF_UP)) {
2954 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
2955 err = -ENETDOWN;
2956 goto out;
2957 }
2958 }
2959
2960 err = -ENOBUFS;
2961 if (cfg->fc_nlinfo.nlh &&
2962 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
2963 table = fib6_get_table(net, cfg->fc_table);
2964 if (!table) {
2965 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
2966 table = fib6_new_table(net, cfg->fc_table);
2967 }
2968 } else {
2969 table = fib6_new_table(net, cfg->fc_table);
2970 }
2971
2972 if (!table)
2973 goto out;
2974
2975 err = -ENOMEM;
2976 rt = fib6_info_alloc(gfp_flags);
2977 if (!rt)
2978 goto out;
2979
2980 rt->fib6_metrics = ip_fib_metrics_init(net, cfg->fc_mx, cfg->fc_mx_len);
2981 if (IS_ERR(rt->fib6_metrics)) {
2982 err = PTR_ERR(rt->fib6_metrics);
2983 /* Do not leave garbage there. */
2984 rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
2985 goto out;
2986 }
2987
2988 if (cfg->fc_flags & RTF_ADDRCONF)
2989 rt->dst_nocount = true;
2990
2991 if (cfg->fc_flags & RTF_EXPIRES)
2992 fib6_set_expires(rt, jiffies +
2993 clock_t_to_jiffies(cfg->fc_expires));
2994 else
2995 fib6_clean_expires(rt);
2996
2997 if (cfg->fc_protocol == RTPROT_UNSPEC)
2998 cfg->fc_protocol = RTPROT_BOOT;
2999 rt->fib6_protocol = cfg->fc_protocol;
3000
3001 addr_type = ipv6_addr_type(&cfg->fc_dst);
3002
3003 if (cfg->fc_encap) {
3004 struct lwtunnel_state *lwtstate;
3005
3006 err = lwtunnel_build_state(cfg->fc_encap_type,
3007 cfg->fc_encap, AF_INET6, cfg,
3008 &lwtstate, extack);
3009 if (err)
3010 goto out;
3011 rt->fib6_nh.nh_lwtstate = lwtstate_get(lwtstate);
3012 }
3013
3014 ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
3015 rt->fib6_dst.plen = cfg->fc_dst_len;
3016 if (rt->fib6_dst.plen == 128)
3017 rt->dst_host = true;
3018
3019 #ifdef CONFIG_IPV6_SUBTREES
3020 ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3021 rt->fib6_src.plen = cfg->fc_src_len;
3022 #endif
3023
3024 rt->fib6_metric = cfg->fc_metric;
3025 rt->fib6_nh.nh_weight = 1;
3026
3027 rt->fib6_type = cfg->fc_type;
3028
3029 /* We cannot add true routes via loopback here,
3030 they would result in kernel looping; promote them to reject routes
3031 */
3032 if ((cfg->fc_flags & RTF_REJECT) ||
3033 (dev && (dev->flags & IFF_LOOPBACK) &&
3034 !(addr_type & IPV6_ADDR_LOOPBACK) &&
3035 !(cfg->fc_flags & RTF_LOCAL))) {
3036 /* hold loopback dev/idev if we haven't done so. */
3037 if (dev != net->loopback_dev) {
3038 if (dev) {
3039 dev_put(dev);
3040 in6_dev_put(idev);
3041 }
3042 dev = net->loopback_dev;
3043 dev_hold(dev);
3044 idev = in6_dev_get(dev);
3045 if (!idev) {
3046 err = -ENODEV;
3047 goto out;
3048 }
3049 }
3050 rt->fib6_flags = RTF_REJECT|RTF_NONEXTHOP;
3051 goto install_route;
3052 }
3053
3054 if (cfg->fc_flags & RTF_GATEWAY) {
3055 err = ip6_validate_gw(net, cfg, &dev, &idev, extack);
3056 if (err)
3057 goto out;
3058
3059 rt->fib6_nh.nh_gw = cfg->fc_gateway;
3060 }
3061
3062 err = -ENODEV;
3063 if (!dev)
3064 goto out;
3065
3066 if (idev->cnf.disable_ipv6) {
3067 NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
3068 err = -EACCES;
3069 goto out;
3070 }
3071
3072 if (!(dev->flags & IFF_UP)) {
3073 NL_SET_ERR_MSG(extack, "Nexthop device is not up");
3074 err = -ENETDOWN;
3075 goto out;
3076 }
3077
3078 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
3079 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3080 NL_SET_ERR_MSG(extack, "Invalid source address");
3081 err = -EINVAL;
3082 goto out;
3083 }
3084 rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3085 rt->fib6_prefsrc.plen = 128;
3086 } else
3087 rt->fib6_prefsrc.plen = 0;
3088
3089 rt->fib6_flags = cfg->fc_flags;
3090
3091 install_route:
3092 if (!(rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
3093 !netif_carrier_ok(dev))
3094 rt->fib6_nh.nh_flags |= RTNH_F_LINKDOWN;
3095 rt->fib6_nh.nh_flags |= (cfg->fc_flags & RTNH_F_ONLINK);
3096 rt->fib6_nh.nh_dev = dev;
3097 rt->fib6_table = table;
3098
3099 if (idev)
3100 in6_dev_put(idev);
3101
3102 return rt;
3103 out:
3104 if (dev)
3105 dev_put(dev);
3106 if (idev)
3107 in6_dev_put(idev);
3108
3109 fib6_info_release(rt);
3110 return ERR_PTR(err);
3111 }
3112
3113 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
3114 struct netlink_ext_ack *extack)
3115 {
3116 struct fib6_info *rt;
3117 int err;
3118
3119 rt = ip6_route_info_create(cfg, gfp_flags, extack);
3120 if (IS_ERR(rt))
3121 return PTR_ERR(rt);
3122
3123 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3124 fib6_info_release(rt);
3125
3126 return err;
3127 }
3128
3129 static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
3130 {
3131 struct net *net = info->nl_net;
3132 struct fib6_table *table;
3133 int err;
3134
3135 if (rt == net->ipv6.fib6_null_entry) {
3136 err = -ENOENT;
3137 goto out;
3138 }
3139
3140 table = rt->fib6_table;
3141 spin_lock_bh(&table->tb6_lock);
3142 err = fib6_del(rt, info);
3143 spin_unlock_bh(&table->tb6_lock);
3144
3145 out:
3146 fib6_info_release(rt);
3147 return err;
3148 }
3149
3150 int ip6_del_rt(struct net *net, struct fib6_info *rt)
3151 {
3152 struct nl_info info = { .nl_net = net };
3153
3154 return __ip6_del_rt(rt, &info);
3155 }
3156
3157 static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
3158 {
3159 struct nl_info *info = &cfg->fc_nlinfo;
3160 struct net *net = info->nl_net;
3161 struct sk_buff *skb = NULL;
3162 struct fib6_table *table;
3163 int err = -ENOENT;
3164
3165 if (rt == net->ipv6.fib6_null_entry)
3166 goto out_put;
3167 table = rt->fib6_table;
3168 spin_lock_bh(&table->tb6_lock);
3169
3170 if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
3171 struct fib6_info *sibling, *next_sibling;
3172
3173 /* prefer to send a single notification with all hops */
3174 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3175 if (skb) {
3176 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3177
3178 if (rt6_fill_node(net, skb, rt, NULL,
3179 NULL, NULL, 0, RTM_DELROUTE,
3180 info->portid, seq, 0) < 0) {
3181 kfree_skb(skb);
3182 skb = NULL;
3183 } else
3184 info->skip_notify = 1;
3185 }
3186
3187 list_for_each_entry_safe(sibling, next_sibling,
3188 &rt->fib6_siblings,
3189 fib6_siblings) {
3190 err = fib6_del(sibling, info);
3191 if (err)
3192 goto out_unlock;
3193 }
3194 }
3195
3196 err = fib6_del(rt, info);
3197 out_unlock:
3198 spin_unlock_bh(&table->tb6_lock);
3199 out_put:
3200 fib6_info_release(rt);
3201
3202 if (skb) {
3203 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3204 info->nlh, gfp_any());
3205 }
3206 return err;
3207 }
3208
3209 static int ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
3210 {
3211 int rc = -ESRCH;
3212
3213 if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
3214 goto out;
3215
3216 if (cfg->fc_flags & RTF_GATEWAY &&
3217 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
3218 goto out;
3219
3220 rc = rt6_remove_exception_rt(rt);
3221 out:
3222 return rc;
3223 }
3224
3225 static int ip6_route_del(struct fib6_config *cfg,
3226 struct netlink_ext_ack *extack)
3227 {
3228 struct rt6_info *rt_cache;
3229 struct fib6_table *table;
3230 struct fib6_info *rt;
3231 struct fib6_node *fn;
3232 int err = -ESRCH;
3233
3234 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
3235 if (!table) {
3236 NL_SET_ERR_MSG(extack, "FIB table does not exist");
3237 return err;
3238 }
3239
3240 rcu_read_lock();
3241
3242 fn = fib6_locate(&table->tb6_root,
3243 &cfg->fc_dst, cfg->fc_dst_len,
3244 &cfg->fc_src, cfg->fc_src_len,
3245 !(cfg->fc_flags & RTF_CACHE));
3246
3247 if (fn) {
3248 for_each_fib6_node_rt_rcu(fn) {
3249 if (cfg->fc_flags & RTF_CACHE) {
3250 int rc;
3251
3252 rt_cache = rt6_find_cached_rt(rt, &cfg->fc_dst,
3253 &cfg->fc_src);
3254 if (rt_cache) {
3255 rc = ip6_del_cached_rt(rt_cache, cfg);
3256 if (rc != -ESRCH) {
3257 rcu_read_unlock();
3258 return rc;
3259 }
3260 }
3261 continue;
3262 }
3263 if (cfg->fc_ifindex &&
3264 (!rt->fib6_nh.nh_dev ||
3265 rt->fib6_nh.nh_dev->ifindex != cfg->fc_ifindex))
3266 continue;
3267 if (cfg->fc_flags & RTF_GATEWAY &&
3268 !ipv6_addr_equal(&cfg->fc_gateway, &rt->fib6_nh.nh_gw))
3269 continue;
3270 if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
3271 continue;
3272 if (cfg->fc_protocol && cfg->fc_protocol != rt->fib6_protocol)
3273 continue;
3274 if (!fib6_info_hold_safe(rt))
3275 continue;
3276 rcu_read_unlock();
3277
3278 /* if gateway was specified only delete the one hop */
3279 if (cfg->fc_flags & RTF_GATEWAY)
3280 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
3281
3282 return __ip6_del_rt_siblings(rt, cfg);
3283 }
3284 }
3285 rcu_read_unlock();
3286
3287 return err;
3288 }
3289
3290 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
3291 {
3292 struct netevent_redirect netevent;
3293 struct rt6_info *rt, *nrt = NULL;
3294 struct ndisc_options ndopts;
3295 struct inet6_dev *in6_dev;
3296 struct neighbour *neigh;
3297 struct fib6_info *from;
3298 struct rd_msg *msg;
3299 int optlen, on_link;
3300 u8 *lladdr;
3301
3302 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
3303 optlen -= sizeof(*msg);
3304
3305 if (optlen < 0) {
3306 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
3307 return;
3308 }
3309
3310 msg = (struct rd_msg *)icmp6_hdr(skb);
3311
3312 if (ipv6_addr_is_multicast(&msg->dest)) {
3313 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
3314 return;
3315 }
3316
3317 on_link = 0;
3318 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
3319 on_link = 1;
3320 } else if (ipv6_addr_type(&msg->target) !=
3321 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
3322 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
3323 return;
3324 }
3325
3326 in6_dev = __in6_dev_get(skb->dev);
3327 if (!in6_dev)
3328 return;
3329 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
3330 return;
3331
3332 /* RFC2461 8.1:
3333 * The IP source address of the Redirect MUST be the same as the current
3334 * first-hop router for the specified ICMP Destination Address.
3335 */
3336
3337 if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
3338 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
3339 return;
3340 }
3341
3342 lladdr = NULL;
3343 if (ndopts.nd_opts_tgt_lladdr) {
3344 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
3345 skb->dev);
3346 if (!lladdr) {
3347 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
3348 return;
3349 }
3350 }
3351
3352 rt = (struct rt6_info *) dst;
3353 if (rt->rt6i_flags & RTF_REJECT) {
3354 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
3355 return;
3356 }
3357
3358 /* Redirect received -> path was valid.
3359 * Look, redirects are sent only in response to data packets,
3360 * so that this nexthop apparently is reachable. --ANK
3361 */
3362 dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
3363
3364 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
3365 if (!neigh)
3366 return;
3367
3368 /*
3369 * We have finally decided to accept it.
3370 */
3371
3372 ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
3373 NEIGH_UPDATE_F_WEAK_OVERRIDE|
3374 NEIGH_UPDATE_F_OVERRIDE|
3375 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
3376 NEIGH_UPDATE_F_ISROUTER)),
3377 NDISC_REDIRECT, &ndopts);
3378
3379 rcu_read_lock();
3380 from = rcu_dereference(rt->from);
3381 /* This fib6_info_hold() is safe here because we hold reference to rt
3382 * and rt already holds reference to fib6_info.
3383 */
3384 fib6_info_hold(from);
3385 rcu_read_unlock();
3386
3387 nrt = ip6_rt_cache_alloc(from, &msg->dest, NULL);
3388 if (!nrt)
3389 goto out;
3390
3391 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
3392 if (on_link)
3393 nrt->rt6i_flags &= ~RTF_GATEWAY;
3394
3395 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
3396
3397 /* No need to remove rt from the exception table if rt is
3398 * a cached route because rt6_insert_exception() will
3399 * takes care of it
3400 */
3401 if (rt6_insert_exception(nrt, from)) {
3402 dst_release_immediate(&nrt->dst);
3403 goto out;
3404 }
3405
3406 netevent.old = &rt->dst;
3407 netevent.new = &nrt->dst;
3408 netevent.daddr = &msg->dest;
3409 netevent.neigh = neigh;
3410 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
3411
3412 out:
3413 fib6_info_release(from);
3414 neigh_release(neigh);
3415 }
3416
3417 #ifdef CONFIG_IPV6_ROUTE_INFO
3418 static struct fib6_info *rt6_get_route_info(struct net *net,
3419 const struct in6_addr *prefix, int prefixlen,
3420 const struct in6_addr *gwaddr,
3421 struct net_device *dev)
3422 {
3423 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
3424 int ifindex = dev->ifindex;
3425 struct fib6_node *fn;
3426 struct fib6_info *rt = NULL;
3427 struct fib6_table *table;
3428
3429 table = fib6_get_table(net, tb_id);
3430 if (!table)
3431 return NULL;
3432
3433 rcu_read_lock();
3434 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
3435 if (!fn)
3436 goto out;
3437
3438 for_each_fib6_node_rt_rcu(fn) {
3439 if (rt->fib6_nh.nh_dev->ifindex != ifindex)
3440 continue;
3441 if ((rt->fib6_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
3442 continue;
3443 if (!ipv6_addr_equal(&rt->fib6_nh.nh_gw, gwaddr))
3444 continue;
3445 if (!fib6_info_hold_safe(rt))
3446 continue;
3447 break;
3448 }
3449 out:
3450 rcu_read_unlock();
3451 return rt;
3452 }
3453
3454 static struct fib6_info *rt6_add_route_info(struct net *net,
3455 const struct in6_addr *prefix, int prefixlen,
3456 const struct in6_addr *gwaddr,
3457 struct net_device *dev,
3458 unsigned int pref)
3459 {
3460 struct fib6_config cfg = {
3461 .fc_metric = IP6_RT_PRIO_USER,
3462 .fc_ifindex = dev->ifindex,
3463 .fc_dst_len = prefixlen,
3464 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
3465 RTF_UP | RTF_PREF(pref),
3466 .fc_protocol = RTPROT_RA,
3467 .fc_type = RTN_UNICAST,
3468 .fc_nlinfo.portid = 0,
3469 .fc_nlinfo.nlh = NULL,
3470 .fc_nlinfo.nl_net = net,
3471 };
3472
3473 cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
3474 cfg.fc_dst = *prefix;
3475 cfg.fc_gateway = *gwaddr;
3476
3477 /* We should treat it as a default route if prefix length is 0. */
3478 if (!prefixlen)
3479 cfg.fc_flags |= RTF_DEFAULT;
3480
3481 ip6_route_add(&cfg, GFP_ATOMIC, NULL);
3482
3483 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
3484 }
3485 #endif
3486
3487 struct fib6_info *rt6_get_dflt_router(struct net *net,
3488 const struct in6_addr *addr,
3489 struct net_device *dev)
3490 {
3491 u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
3492 struct fib6_info *rt;
3493 struct fib6_table *table;
3494
3495 table = fib6_get_table(net, tb_id);
3496 if (!table)
3497 return NULL;
3498
3499 rcu_read_lock();
3500 for_each_fib6_node_rt_rcu(&table->tb6_root) {
3501 if (dev == rt->fib6_nh.nh_dev &&
3502 ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
3503 ipv6_addr_equal(&rt->fib6_nh.nh_gw, addr))
3504 break;
3505 }
3506 if (rt && !fib6_info_hold_safe(rt))
3507 rt = NULL;
3508 rcu_read_unlock();
3509 return rt;
3510 }
3511
3512 struct fib6_info *rt6_add_dflt_router(struct net *net,
3513 const struct in6_addr *gwaddr,
3514 struct net_device *dev,
3515 unsigned int pref)
3516 {
3517 struct fib6_config cfg = {
3518 .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
3519 .fc_metric = IP6_RT_PRIO_USER,
3520 .fc_ifindex = dev->ifindex,
3521 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
3522 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
3523 .fc_protocol = RTPROT_RA,
3524 .fc_type = RTN_UNICAST,
3525 .fc_nlinfo.portid = 0,
3526 .fc_nlinfo.nlh = NULL,
3527 .fc_nlinfo.nl_net = net,
3528 };
3529
3530 cfg.fc_gateway = *gwaddr;
3531
3532 if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
3533 struct fib6_table *table;
3534
3535 table = fib6_get_table(dev_net(dev), cfg.fc_table);
3536 if (table)
3537 table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
3538 }
3539
3540 return rt6_get_dflt_router(net, gwaddr, dev);
3541 }
3542
3543 static void __rt6_purge_dflt_routers(struct net *net,
3544 struct fib6_table *table)
3545 {
3546 struct fib6_info *rt;
3547
3548 restart:
3549 rcu_read_lock();
3550 for_each_fib6_node_rt_rcu(&table->tb6_root) {
3551 struct net_device *dev = fib6_info_nh_dev(rt);
3552 struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
3553
3554 if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
3555 (!idev || idev->cnf.accept_ra != 2) &&
3556 fib6_info_hold_safe(rt)) {
3557 rcu_read_unlock();
3558 ip6_del_rt(net, rt);
3559 goto restart;
3560 }
3561 }
3562 rcu_read_unlock();
3563
3564 table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
3565 }
3566
3567 void rt6_purge_dflt_routers(struct net *net)
3568 {
3569 struct fib6_table *table;
3570 struct hlist_head *head;
3571 unsigned int h;
3572
3573 rcu_read_lock();
3574
3575 for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
3576 head = &net->ipv6.fib_table_hash[h];
3577 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
3578 if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
3579 __rt6_purge_dflt_routers(net, table);
3580 }
3581 }
3582
3583 rcu_read_unlock();
3584 }
3585
3586 static void rtmsg_to_fib6_config(struct net *net,
3587 struct in6_rtmsg *rtmsg,
3588 struct fib6_config *cfg)
3589 {
3590 *cfg = (struct fib6_config){
3591 .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
3592 : RT6_TABLE_MAIN,
3593 .fc_ifindex = rtmsg->rtmsg_ifindex,
3594 .fc_metric = rtmsg->rtmsg_metric,
3595 .fc_expires = rtmsg->rtmsg_info,
3596 .fc_dst_len = rtmsg->rtmsg_dst_len,
3597 .fc_src_len = rtmsg->rtmsg_src_len,
3598 .fc_flags = rtmsg->rtmsg_flags,
3599 .fc_type = rtmsg->rtmsg_type,
3600
3601 .fc_nlinfo.nl_net = net,
3602
3603 .fc_dst = rtmsg->rtmsg_dst,
3604 .fc_src = rtmsg->rtmsg_src,
3605 .fc_gateway = rtmsg->rtmsg_gateway,
3606 };
3607 }
3608
3609 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
3610 {
3611 struct fib6_config cfg;
3612 struct in6_rtmsg rtmsg;
3613 int err;
3614
3615 switch (cmd) {
3616 case SIOCADDRT: /* Add a route */
3617 case SIOCDELRT: /* Delete a route */
3618 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3619 return -EPERM;
3620 err = copy_from_user(&rtmsg, arg,
3621 sizeof(struct in6_rtmsg));
3622 if (err)
3623 return -EFAULT;
3624
3625 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
3626
3627 rtnl_lock();
3628 switch (cmd) {
3629 case SIOCADDRT:
3630 err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
3631 break;
3632 case SIOCDELRT:
3633 err = ip6_route_del(&cfg, NULL);
3634 break;
3635 default:
3636 err = -EINVAL;
3637 }
3638 rtnl_unlock();
3639
3640 return err;
3641 }
3642
3643 return -EINVAL;
3644 }
3645
3646 /*
3647 * Drop the packet on the floor
3648 */
3649
3650 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
3651 {
3652 int type;
3653 struct dst_entry *dst = skb_dst(skb);
3654 switch (ipstats_mib_noroutes) {
3655 case IPSTATS_MIB_INNOROUTES:
3656 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
3657 if (type == IPV6_ADDR_ANY) {
3658 IP6_INC_STATS(dev_net(dst->dev),
3659 __in6_dev_get_safely(skb->dev),
3660 IPSTATS_MIB_INADDRERRORS);
3661 break;
3662 }
3663 /* FALLTHROUGH */
3664 case IPSTATS_MIB_OUTNOROUTES:
3665 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
3666 ipstats_mib_noroutes);
3667 break;
3668 }
3669 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
3670 kfree_skb(skb);
3671 return 0;
3672 }
3673
3674 static int ip6_pkt_discard(struct sk_buff *skb)
3675 {
3676 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
3677 }
3678
3679 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
3680 {
3681 skb->dev = skb_dst(skb)->dev;
3682 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
3683 }
3684
3685 static int ip6_pkt_prohibit(struct sk_buff *skb)
3686 {
3687 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
3688 }
3689
3690 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
3691 {
3692 skb->dev = skb_dst(skb)->dev;
3693 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
3694 }
3695
3696 /*
3697 * Allocate a dst for local (unicast / anycast) address.
3698 */
3699
3700 struct fib6_info *addrconf_f6i_alloc(struct net *net,
3701 struct inet6_dev *idev,
3702 const struct in6_addr *addr,
3703 bool anycast, gfp_t gfp_flags)
3704 {
3705 u32 tb_id;
3706 struct net_device *dev = idev->dev;
3707 struct fib6_info *f6i;
3708
3709 f6i = fib6_info_alloc(gfp_flags);
3710 if (!f6i)
3711 return ERR_PTR(-ENOMEM);
3712
3713 f6i->fib6_metrics = ip_fib_metrics_init(net, NULL, 0);
3714 f6i->dst_nocount = true;
3715 f6i->dst_host = true;
3716 f6i->fib6_protocol = RTPROT_KERNEL;
3717 f6i->fib6_flags = RTF_UP | RTF_NONEXTHOP;
3718 if (anycast) {
3719 f6i->fib6_type = RTN_ANYCAST;
3720 f6i->fib6_flags |= RTF_ANYCAST;
3721 } else {
3722 f6i->fib6_type = RTN_LOCAL;
3723 f6i->fib6_flags |= RTF_LOCAL;
3724 }
3725
3726 f6i->fib6_nh.nh_gw = *addr;
3727 dev_hold(dev);
3728 f6i->fib6_nh.nh_dev = dev;
3729 f6i->fib6_dst.addr = *addr;
3730 f6i->fib6_dst.plen = 128;
3731 tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
3732 f6i->fib6_table = fib6_get_table(net, tb_id);
3733
3734 return f6i;
3735 }
3736
3737 /* remove deleted ip from prefsrc entries */
3738 struct arg_dev_net_ip {
3739 struct net_device *dev;
3740 struct net *net;
3741 struct in6_addr *addr;
3742 };
3743
3744 static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg)
3745 {
3746 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
3747 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
3748 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
3749
3750 if (((void *)rt->fib6_nh.nh_dev == dev || !dev) &&
3751 rt != net->ipv6.fib6_null_entry &&
3752 ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr)) {
3753 spin_lock_bh(&rt6_exception_lock);
3754 /* remove prefsrc entry */
3755 rt->fib6_prefsrc.plen = 0;
3756 spin_unlock_bh(&rt6_exception_lock);
3757 }
3758 return 0;
3759 }
3760
3761 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
3762 {
3763 struct net *net = dev_net(ifp->idev->dev);
3764 struct arg_dev_net_ip adni = {
3765 .dev = ifp->idev->dev,
3766 .net = net,
3767 .addr = &ifp->addr,
3768 };
3769 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
3770 }
3771
3772 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
3773
3774 /* Remove routers and update dst entries when gateway turn into host. */
3775 static int fib6_clean_tohost(struct fib6_info *rt, void *arg)
3776 {
3777 struct in6_addr *gateway = (struct in6_addr *)arg;
3778
3779 if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
3780 ipv6_addr_equal(gateway, &rt->fib6_nh.nh_gw)) {
3781 return -1;
3782 }
3783
3784 /* Further clean up cached routes in exception table.
3785 * This is needed because cached route may have a different
3786 * gateway than its 'parent' in the case of an ip redirect.
3787 */
3788 rt6_exceptions_clean_tohost(rt, gateway);
3789
3790 return 0;
3791 }
3792
3793 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
3794 {
3795 fib6_clean_all(net, fib6_clean_tohost, gateway);
3796 }
3797
3798 struct arg_netdev_event {
3799 const struct net_device *dev;
3800 union {
3801 unsigned int nh_flags;
3802 unsigned long event;
3803 };
3804 };
3805
3806 static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
3807 {
3808 struct fib6_info *iter;
3809 struct fib6_node *fn;
3810
3811 fn = rcu_dereference_protected(rt->fib6_node,
3812 lockdep_is_held(&rt->fib6_table->tb6_lock));
3813 iter = rcu_dereference_protected(fn->leaf,
3814 lockdep_is_held(&rt->fib6_table->tb6_lock));
3815 while (iter) {
3816 if (iter->fib6_metric == rt->fib6_metric &&
3817 rt6_qualify_for_ecmp(iter))
3818 return iter;
3819 iter = rcu_dereference_protected(iter->fib6_next,
3820 lockdep_is_held(&rt->fib6_table->tb6_lock));
3821 }
3822
3823 return NULL;
3824 }
3825
3826 static bool rt6_is_dead(const struct fib6_info *rt)
3827 {
3828 if (rt->fib6_nh.nh_flags & RTNH_F_DEAD ||
3829 (rt->fib6_nh.nh_flags & RTNH_F_LINKDOWN &&
3830 fib6_ignore_linkdown(rt)))
3831 return true;
3832
3833 return false;
3834 }
3835
3836 static int rt6_multipath_total_weight(const struct fib6_info *rt)
3837 {
3838 struct fib6_info *iter;
3839 int total = 0;
3840
3841 if (!rt6_is_dead(rt))
3842 total += rt->fib6_nh.nh_weight;
3843
3844 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
3845 if (!rt6_is_dead(iter))
3846 total += iter->fib6_nh.nh_weight;
3847 }
3848
3849 return total;
3850 }
3851
3852 static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
3853 {
3854 int upper_bound = -1;
3855
3856 if (!rt6_is_dead(rt)) {
3857 *weight += rt->fib6_nh.nh_weight;
3858 upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
3859 total) - 1;
3860 }
3861 atomic_set(&rt->fib6_nh.nh_upper_bound, upper_bound);
3862 }
3863
3864 static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
3865 {
3866 struct fib6_info *iter;
3867 int weight = 0;
3868
3869 rt6_upper_bound_set(rt, &weight, total);
3870
3871 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
3872 rt6_upper_bound_set(iter, &weight, total);
3873 }
3874
3875 void rt6_multipath_rebalance(struct fib6_info *rt)
3876 {
3877 struct fib6_info *first;
3878 int total;
3879
3880 /* In case the entire multipath route was marked for flushing,
3881 * then there is no need to rebalance upon the removal of every
3882 * sibling route.
3883 */
3884 if (!rt->fib6_nsiblings || rt->should_flush)
3885 return;
3886
3887 /* During lookup routes are evaluated in order, so we need to
3888 * make sure upper bounds are assigned from the first sibling
3889 * onwards.
3890 */
3891 first = rt6_multipath_first_sibling(rt);
3892 if (WARN_ON_ONCE(!first))
3893 return;
3894
3895 total = rt6_multipath_total_weight(first);
3896 rt6_multipath_upper_bound_set(first, total);
3897 }
3898
3899 static int fib6_ifup(struct fib6_info *rt, void *p_arg)
3900 {
3901 const struct arg_netdev_event *arg = p_arg;
3902 struct net *net = dev_net(arg->dev);
3903
3904 if (rt != net->ipv6.fib6_null_entry && rt->fib6_nh.nh_dev == arg->dev) {
3905 rt->fib6_nh.nh_flags &= ~arg->nh_flags;
3906 fib6_update_sernum_upto_root(net, rt);
3907 rt6_multipath_rebalance(rt);
3908 }
3909
3910 return 0;
3911 }
3912
3913 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags)
3914 {
3915 struct arg_netdev_event arg = {
3916 .dev = dev,
3917 {
3918 .nh_flags = nh_flags,
3919 },
3920 };
3921
3922 if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev))
3923 arg.nh_flags |= RTNH_F_LINKDOWN;
3924
3925 fib6_clean_all(dev_net(dev), fib6_ifup, &arg);
3926 }
3927
3928 static bool rt6_multipath_uses_dev(const struct fib6_info *rt,
3929 const struct net_device *dev)
3930 {
3931 struct fib6_info *iter;
3932
3933 if (rt->fib6_nh.nh_dev == dev)
3934 return true;
3935 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
3936 if (iter->fib6_nh.nh_dev == dev)
3937 return true;
3938
3939 return false;
3940 }
3941
3942 static void rt6_multipath_flush(struct fib6_info *rt)
3943 {
3944 struct fib6_info *iter;
3945
3946 rt->should_flush = 1;
3947 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
3948 iter->should_flush = 1;
3949 }
3950
3951 static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt,
3952 const struct net_device *down_dev)
3953 {
3954 struct fib6_info *iter;
3955 unsigned int dead = 0;
3956
3957 if (rt->fib6_nh.nh_dev == down_dev ||
3958 rt->fib6_nh.nh_flags & RTNH_F_DEAD)
3959 dead++;
3960 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
3961 if (iter->fib6_nh.nh_dev == down_dev ||
3962 iter->fib6_nh.nh_flags & RTNH_F_DEAD)
3963 dead++;
3964
3965 return dead;
3966 }
3967
3968 static void rt6_multipath_nh_flags_set(struct fib6_info *rt,
3969 const struct net_device *dev,
3970 unsigned int nh_flags)
3971 {
3972 struct fib6_info *iter;
3973
3974 if (rt->fib6_nh.nh_dev == dev)
3975 rt->fib6_nh.nh_flags |= nh_flags;
3976 list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
3977 if (iter->fib6_nh.nh_dev == dev)
3978 iter->fib6_nh.nh_flags |= nh_flags;
3979 }
3980
3981 /* called with write lock held for table with rt */
3982 static int fib6_ifdown(struct fib6_info *rt, void *p_arg)
3983 {
3984 const struct arg_netdev_event *arg = p_arg;
3985 const struct net_device *dev = arg->dev;
3986 struct net *net = dev_net(dev);
3987
3988 if (rt == net->ipv6.fib6_null_entry)
3989 return 0;
3990
3991 switch (arg->event) {
3992 case NETDEV_UNREGISTER:
3993 return rt->fib6_nh.nh_dev == dev ? -1 : 0;
3994 case NETDEV_DOWN:
3995 if (rt->should_flush)
3996 return -1;
3997 if (!rt->fib6_nsiblings)
3998 return rt->fib6_nh.nh_dev == dev ? -1 : 0;
3999 if (rt6_multipath_uses_dev(rt, dev)) {
4000 unsigned int count;
4001
4002 count = rt6_multipath_dead_count(rt, dev);
4003 if (rt->fib6_nsiblings + 1 == count) {
4004 rt6_multipath_flush(rt);
4005 return -1;
4006 }
4007 rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
4008 RTNH_F_LINKDOWN);
4009 fib6_update_sernum(net, rt);
4010 rt6_multipath_rebalance(rt);
4011 }
4012 return -2;
4013 case NETDEV_CHANGE:
4014 if (rt->fib6_nh.nh_dev != dev ||
4015 rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
4016 break;
4017 rt->fib6_nh.nh_flags |= RTNH_F_LINKDOWN;
4018 rt6_multipath_rebalance(rt);
4019 break;
4020 }
4021
4022 return 0;
4023 }
4024
4025 void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
4026 {
4027 struct arg_netdev_event arg = {
4028 .dev = dev,
4029 {
4030 .event = event,
4031 },
4032 };
4033 struct net *net = dev_net(dev);
4034
4035 if (net->ipv6.sysctl.skip_notify_on_dev_down)
4036 fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
4037 else
4038 fib6_clean_all(net, fib6_ifdown, &arg);
4039 }
4040
4041 void rt6_disable_ip(struct net_device *dev, unsigned long event)
4042 {
4043 rt6_sync_down_dev(dev, event);
4044 rt6_uncached_list_flush_dev(dev_net(dev), dev);
4045 neigh_ifdown(&nd_tbl, dev);
4046 }
4047
4048 struct rt6_mtu_change_arg {
4049 struct net_device *dev;
4050 unsigned int mtu;
4051 };
4052
4053 static int rt6_mtu_change_route(struct fib6_info *rt, void *p_arg)
4054 {
4055 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
4056 struct inet6_dev *idev;
4057
4058 /* In IPv6 pmtu discovery is not optional,
4059 so that RTAX_MTU lock cannot disable it.
4060 We still use this lock to block changes
4061 caused by addrconf/ndisc.
4062 */
4063
4064 idev = __in6_dev_get(arg->dev);
4065 if (!idev)
4066 return 0;
4067
4068 /* For administrative MTU increase, there is no way to discover
4069 IPv6 PMTU increase, so PMTU increase should be updated here.
4070 Since RFC 1981 doesn't include administrative MTU increase
4071 update PMTU increase is a MUST. (i.e. jumbo frame)
4072 */
4073 if (rt->fib6_nh.nh_dev == arg->dev &&
4074 !fib6_metric_locked(rt, RTAX_MTU)) {
4075 u32 mtu = rt->fib6_pmtu;
4076
4077 if (mtu >= arg->mtu ||
4078 (mtu < arg->mtu && mtu == idev->cnf.mtu6))
4079 fib6_metric_set(rt, RTAX_MTU, arg->mtu);
4080
4081 spin_lock_bh(&rt6_exception_lock);
4082 rt6_exceptions_update_pmtu(idev, rt, arg->mtu);
4083 spin_unlock_bh(&rt6_exception_lock);
4084 }
4085 return 0;
4086 }
4087
4088 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
4089 {
4090 struct rt6_mtu_change_arg arg = {
4091 .dev = dev,
4092 .mtu = mtu,
4093 };
4094
4095 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
4096 }
4097
4098 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
4099 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
4100 [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
4101 [RTA_OIF] = { .type = NLA_U32 },
4102 [RTA_IIF] = { .type = NLA_U32 },
4103 [RTA_PRIORITY] = { .type = NLA_U32 },
4104 [RTA_METRICS] = { .type = NLA_NESTED },
4105 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
4106 [RTA_PREF] = { .type = NLA_U8 },
4107 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
4108 [RTA_ENCAP] = { .type = NLA_NESTED },
4109 [RTA_EXPIRES] = { .type = NLA_U32 },
4110 [RTA_UID] = { .type = NLA_U32 },
4111 [RTA_MARK] = { .type = NLA_U32 },
4112 [RTA_TABLE] = { .type = NLA_U32 },
4113 [RTA_IP_PROTO] = { .type = NLA_U8 },
4114 [RTA_SPORT] = { .type = NLA_U16 },
4115 [RTA_DPORT] = { .type = NLA_U16 },
4116 };
4117
4118 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
4119 struct fib6_config *cfg,
4120 struct netlink_ext_ack *extack)
4121 {
4122 struct rtmsg *rtm;
4123 struct nlattr *tb[RTA_MAX+1];
4124 unsigned int pref;
4125 int err;
4126
4127 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy,
4128 extack);
4129 if (err < 0)
4130 goto errout;
4131
4132 err = -EINVAL;
4133 rtm = nlmsg_data(nlh);
4134
4135 *cfg = (struct fib6_config){
4136 .fc_table = rtm->rtm_table,
4137 .fc_dst_len = rtm->rtm_dst_len,
4138 .fc_src_len = rtm->rtm_src_len,
4139 .fc_flags = RTF_UP,
4140 .fc_protocol = rtm->rtm_protocol,
4141 .fc_type = rtm->rtm_type,
4142
4143 .fc_nlinfo.portid = NETLINK_CB(skb).portid,
4144 .fc_nlinfo.nlh = nlh,
4145 .fc_nlinfo.nl_net = sock_net(skb->sk),
4146 };
4147
4148 if (rtm->rtm_type == RTN_UNREACHABLE ||
4149 rtm->rtm_type == RTN_BLACKHOLE ||
4150 rtm->rtm_type == RTN_PROHIBIT ||
4151 rtm->rtm_type == RTN_THROW)
4152 cfg->fc_flags |= RTF_REJECT;
4153
4154 if (rtm->rtm_type == RTN_LOCAL)
4155 cfg->fc_flags |= RTF_LOCAL;
4156
4157 if (rtm->rtm_flags & RTM_F_CLONED)
4158 cfg->fc_flags |= RTF_CACHE;
4159
4160 cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
4161
4162 if (tb[RTA_GATEWAY]) {
4163 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
4164 cfg->fc_flags |= RTF_GATEWAY;
4165 }
4166
4167 if (tb[RTA_DST]) {
4168 int plen = (rtm->rtm_dst_len + 7) >> 3;
4169
4170 if (nla_len(tb[RTA_DST]) < plen)
4171 goto errout;
4172
4173 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
4174 }
4175
4176 if (tb[RTA_SRC]) {
4177 int plen = (rtm->rtm_src_len + 7) >> 3;
4178
4179 if (nla_len(tb[RTA_SRC]) < plen)
4180 goto errout;
4181
4182 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
4183 }
4184
4185 if (tb[RTA_PREFSRC])
4186 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
4187
4188 if (tb[RTA_OIF])
4189 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
4190
4191 if (tb[RTA_PRIORITY])
4192 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
4193
4194 if (tb[RTA_METRICS]) {
4195 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
4196 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
4197 }
4198
4199 if (tb[RTA_TABLE])
4200 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
4201
4202 if (tb[RTA_MULTIPATH]) {
4203 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
4204 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
4205
4206 err = lwtunnel_valid_encap_type_attr(cfg->fc_mp,
4207 cfg->fc_mp_len, extack);
4208 if (err < 0)
4209 goto errout;
4210 }
4211
4212 if (tb[RTA_PREF]) {
4213 pref = nla_get_u8(tb[RTA_PREF]);
4214 if (pref != ICMPV6_ROUTER_PREF_LOW &&
4215 pref != ICMPV6_ROUTER_PREF_HIGH)
4216 pref = ICMPV6_ROUTER_PREF_MEDIUM;
4217 cfg->fc_flags |= RTF_PREF(pref);
4218 }
4219
4220 if (tb[RTA_ENCAP])
4221 cfg->fc_encap = tb[RTA_ENCAP];
4222
4223 if (tb[RTA_ENCAP_TYPE]) {
4224 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
4225
4226 err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
4227 if (err < 0)
4228 goto errout;
4229 }
4230
4231 if (tb[RTA_EXPIRES]) {
4232 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
4233
4234 if (addrconf_finite_timeout(timeout)) {
4235 cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
4236 cfg->fc_flags |= RTF_EXPIRES;
4237 }
4238 }
4239
4240 err = 0;
4241 errout:
4242 return err;
4243 }
4244
4245 struct rt6_nh {
4246 struct fib6_info *fib6_info;
4247 struct fib6_config r_cfg;
4248 struct list_head next;
4249 };
4250
4251 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
4252 {
4253 struct rt6_nh *nh;
4254
4255 list_for_each_entry(nh, rt6_nh_list, next) {
4256 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6c nexthop %pI6c ifi %d\n",
4257 &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
4258 nh->r_cfg.fc_ifindex);
4259 }
4260 }
4261
4262 static int ip6_route_info_append(struct net *net,
4263 struct list_head *rt6_nh_list,
4264 struct fib6_info *rt,
4265 struct fib6_config *r_cfg)
4266 {
4267 struct rt6_nh *nh;
4268 int err = -EEXIST;
4269
4270 list_for_each_entry(nh, rt6_nh_list, next) {
4271 /* check if fib6_info already exists */
4272 if (rt6_duplicate_nexthop(nh->fib6_info, rt))
4273 return err;
4274 }
4275
4276 nh = kzalloc(sizeof(*nh), GFP_KERNEL);
4277 if (!nh)
4278 return -ENOMEM;
4279 nh->fib6_info = rt;
4280 memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
4281 list_add_tail(&nh->next, rt6_nh_list);
4282
4283 return 0;
4284 }
4285
4286 static void ip6_route_mpath_notify(struct fib6_info *rt,
4287 struct fib6_info *rt_last,
4288 struct nl_info *info,
4289 __u16 nlflags)
4290 {
4291 /* if this is an APPEND route, then rt points to the first route
4292 * inserted and rt_last points to last route inserted. Userspace
4293 * wants a consistent dump of the route which starts at the first
4294 * nexthop. Since sibling routes are always added at the end of
4295 * the list, find the first sibling of the last route appended
4296 */
4297 if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
4298 rt = list_first_entry(&rt_last->fib6_siblings,
4299 struct fib6_info,
4300 fib6_siblings);
4301 }
4302
4303 if (rt)
4304 inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
4305 }
4306
4307 static int ip6_route_multipath_add(struct fib6_config *cfg,
4308 struct netlink_ext_ack *extack)
4309 {
4310 struct fib6_info *rt_notif = NULL, *rt_last = NULL;
4311 struct nl_info *info = &cfg->fc_nlinfo;
4312 struct fib6_config r_cfg;
4313 struct rtnexthop *rtnh;
4314 struct fib6_info *rt;
4315 struct rt6_nh *err_nh;
4316 struct rt6_nh *nh, *nh_safe;
4317 __u16 nlflags;
4318 int remaining;
4319 int attrlen;
4320 int err = 1;
4321 int nhn = 0;
4322 int replace = (cfg->fc_nlinfo.nlh &&
4323 (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
4324 LIST_HEAD(rt6_nh_list);
4325
4326 nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
4327 if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
4328 nlflags |= NLM_F_APPEND;
4329
4330 remaining = cfg->fc_mp_len;
4331 rtnh = (struct rtnexthop *)cfg->fc_mp;
4332
4333 /* Parse a Multipath Entry and build a list (rt6_nh_list) of
4334 * fib6_info structs per nexthop
4335 */
4336 while (rtnh_ok(rtnh, remaining)) {
4337 memcpy(&r_cfg, cfg, sizeof(*cfg));
4338 if (rtnh->rtnh_ifindex)
4339 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
4340
4341 attrlen = rtnh_attrlen(rtnh);
4342 if (attrlen > 0) {
4343 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
4344
4345 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
4346 if (nla) {
4347 r_cfg.fc_gateway = nla_get_in6_addr(nla);
4348 r_cfg.fc_flags |= RTF_GATEWAY;
4349 }
4350 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
4351 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
4352 if (nla)
4353 r_cfg.fc_encap_type = nla_get_u16(nla);
4354 }
4355
4356 r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
4357 rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
4358 if (IS_ERR(rt)) {
4359 err = PTR_ERR(rt);
4360 rt = NULL;
4361 goto cleanup;
4362 }
4363 if (!rt6_qualify_for_ecmp(rt)) {
4364 err = -EINVAL;
4365 NL_SET_ERR_MSG(extack,
4366 "Device only routes can not be added for IPv6 using the multipath API.");
4367 fib6_info_release(rt);
4368 goto cleanup;
4369 }
4370
4371 rt->fib6_nh.nh_weight = rtnh->rtnh_hops + 1;
4372
4373 err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
4374 rt, &r_cfg);
4375 if (err) {
4376 fib6_info_release(rt);
4377 goto cleanup;
4378 }
4379
4380 rtnh = rtnh_next(rtnh, &remaining);
4381 }
4382
4383 /* for add and replace send one notification with all nexthops.
4384 * Skip the notification in fib6_add_rt2node and send one with
4385 * the full route when done
4386 */
4387 info->skip_notify = 1;
4388
4389 err_nh = NULL;
4390 list_for_each_entry(nh, &rt6_nh_list, next) {
4391 err = __ip6_ins_rt(nh->fib6_info, info, extack);
4392 fib6_info_release(nh->fib6_info);
4393
4394 if (!err) {
4395 /* save reference to last route successfully inserted */
4396 rt_last = nh->fib6_info;
4397
4398 /* save reference to first route for notification */
4399 if (!rt_notif)
4400 rt_notif = nh->fib6_info;
4401 }
4402
4403 /* nh->fib6_info is used or freed at this point, reset to NULL*/
4404 nh->fib6_info = NULL;
4405 if (err) {
4406 if (replace && nhn)
4407 ip6_print_replace_route_err(&rt6_nh_list);
4408 err_nh = nh;
4409 goto add_errout;
4410 }
4411
4412 /* Because each route is added like a single route we remove
4413 * these flags after the first nexthop: if there is a collision,
4414 * we have already failed to add the first nexthop:
4415 * fib6_add_rt2node() has rejected it; when replacing, old
4416 * nexthops have been replaced by first new, the rest should
4417 * be added to it.
4418 */
4419 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
4420 NLM_F_REPLACE);
4421 nhn++;
4422 }
4423
4424 /* success ... tell user about new route */
4425 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
4426 goto cleanup;
4427
4428 add_errout:
4429 /* send notification for routes that were added so that
4430 * the delete notifications sent by ip6_route_del are
4431 * coherent
4432 */
4433 if (rt_notif)
4434 ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
4435
4436 /* Delete routes that were already added */
4437 list_for_each_entry(nh, &rt6_nh_list, next) {
4438 if (err_nh == nh)
4439 break;
4440 ip6_route_del(&nh->r_cfg, extack);
4441 }
4442
4443 cleanup:
4444 list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
4445 if (nh->fib6_info)
4446 fib6_info_release(nh->fib6_info);
4447 list_del(&nh->next);
4448 kfree(nh);
4449 }
4450
4451 return err;
4452 }
4453
4454 static int ip6_route_multipath_del(struct fib6_config *cfg,
4455 struct netlink_ext_ack *extack)
4456 {
4457 struct fib6_config r_cfg;
4458 struct rtnexthop *rtnh;
4459 int remaining;
4460 int attrlen;
4461 int err = 1, last_err = 0;
4462
4463 remaining = cfg->fc_mp_len;
4464 rtnh = (struct rtnexthop *)cfg->fc_mp;
4465
4466 /* Parse a Multipath Entry */
4467 while (rtnh_ok(rtnh, remaining)) {
4468 memcpy(&r_cfg, cfg, sizeof(*cfg));
4469 if (rtnh->rtnh_ifindex)
4470 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
4471
4472 attrlen = rtnh_attrlen(rtnh);
4473 if (attrlen > 0) {
4474 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
4475
4476 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
4477 if (nla) {
4478 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
4479 r_cfg.fc_flags |= RTF_GATEWAY;
4480 }
4481 }
4482 err = ip6_route_del(&r_cfg, extack);
4483 if (err)
4484 last_err = err;
4485
4486 rtnh = rtnh_next(rtnh, &remaining);
4487 }
4488
4489 return last_err;
4490 }
4491
4492 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
4493 struct netlink_ext_ack *extack)
4494 {
4495 struct fib6_config cfg;
4496 int err;
4497
4498 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
4499 if (err < 0)
4500 return err;
4501
4502 if (cfg.fc_mp)
4503 return ip6_route_multipath_del(&cfg, extack);
4504 else {
4505 cfg.fc_delete_all_nh = 1;
4506 return ip6_route_del(&cfg, extack);
4507 }
4508 }
4509
4510 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
4511 struct netlink_ext_ack *extack)
4512 {
4513 struct fib6_config cfg;
4514 int err;
4515
4516 err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
4517 if (err < 0)
4518 return err;
4519
4520 if (cfg.fc_mp)
4521 return ip6_route_multipath_add(&cfg, extack);
4522 else
4523 return ip6_route_add(&cfg, GFP_KERNEL, extack);
4524 }
4525
4526 static size_t rt6_nlmsg_size(struct fib6_info *rt)
4527 {
4528 int nexthop_len = 0;
4529
4530 if (rt->fib6_nsiblings) {
4531 nexthop_len = nla_total_size(0) /* RTA_MULTIPATH */
4532 + NLA_ALIGN(sizeof(struct rtnexthop))
4533 + nla_total_size(16) /* RTA_GATEWAY */
4534 + lwtunnel_get_encap_size(rt->fib6_nh.nh_lwtstate);
4535
4536 nexthop_len *= rt->fib6_nsiblings;
4537 }
4538
4539 return NLMSG_ALIGN(sizeof(struct rtmsg))
4540 + nla_total_size(16) /* RTA_SRC */
4541 + nla_total_size(16) /* RTA_DST */
4542 + nla_total_size(16) /* RTA_GATEWAY */
4543 + nla_total_size(16) /* RTA_PREFSRC */
4544 + nla_total_size(4) /* RTA_TABLE */
4545 + nla_total_size(4) /* RTA_IIF */
4546 + nla_total_size(4) /* RTA_OIF */
4547 + nla_total_size(4) /* RTA_PRIORITY */
4548 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
4549 + nla_total_size(sizeof(struct rta_cacheinfo))
4550 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
4551 + nla_total_size(1) /* RTA_PREF */
4552 + lwtunnel_get_encap_size(rt->fib6_nh.nh_lwtstate)
4553 + nexthop_len;
4554 }
4555
4556 static int rt6_nexthop_info(struct sk_buff *skb, struct fib6_info *rt,
4557 unsigned int *flags, bool skip_oif)
4558 {
4559 if (rt->fib6_nh.nh_flags & RTNH_F_DEAD)
4560 *flags |= RTNH_F_DEAD;
4561
4562 if (rt->fib6_nh.nh_flags & RTNH_F_LINKDOWN) {
4563 *flags |= RTNH_F_LINKDOWN;
4564
4565 rcu_read_lock();
4566 if (fib6_ignore_linkdown(rt))
4567 *flags |= RTNH_F_DEAD;
4568 rcu_read_unlock();
4569 }
4570
4571 if (rt->fib6_flags & RTF_GATEWAY) {
4572 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->fib6_nh.nh_gw) < 0)
4573 goto nla_put_failure;
4574 }
4575
4576 *flags |= (rt->fib6_nh.nh_flags & RTNH_F_ONLINK);
4577 if (rt->fib6_nh.nh_flags & RTNH_F_OFFLOAD)
4578 *flags |= RTNH_F_OFFLOAD;
4579
4580 /* not needed for multipath encoding b/c it has a rtnexthop struct */
4581 if (!skip_oif && rt->fib6_nh.nh_dev &&
4582 nla_put_u32(skb, RTA_OIF, rt->fib6_nh.nh_dev->ifindex))
4583 goto nla_put_failure;
4584
4585 if (rt->fib6_nh.nh_lwtstate &&
4586 lwtunnel_fill_encap(skb, rt->fib6_nh.nh_lwtstate) < 0)
4587 goto nla_put_failure;
4588
4589 return 0;
4590
4591 nla_put_failure:
4592 return -EMSGSIZE;
4593 }
4594
4595 /* add multipath next hop */
4596 static int rt6_add_nexthop(struct sk_buff *skb, struct fib6_info *rt)
4597 {
4598 const struct net_device *dev = rt->fib6_nh.nh_dev;
4599 struct rtnexthop *rtnh;
4600 unsigned int flags = 0;
4601
4602 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
4603 if (!rtnh)
4604 goto nla_put_failure;
4605
4606 rtnh->rtnh_hops = rt->fib6_nh.nh_weight - 1;
4607 rtnh->rtnh_ifindex = dev ? dev->ifindex : 0;
4608
4609 if (rt6_nexthop_info(skb, rt, &flags, true) < 0)
4610 goto nla_put_failure;
4611
4612 rtnh->rtnh_flags = flags;
4613
4614 /* length of rtnetlink header + attributes */
4615 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
4616
4617 return 0;
4618
4619 nla_put_failure:
4620 return -EMSGSIZE;
4621 }
4622
4623 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
4624 struct fib6_info *rt, struct dst_entry *dst,
4625 struct in6_addr *dest, struct in6_addr *src,
4626 int iif, int type, u32 portid, u32 seq,
4627 unsigned int flags)
4628 {
4629 struct rt6_info *rt6 = (struct rt6_info *)dst;
4630 struct rt6key *rt6_dst, *rt6_src;
4631 u32 *pmetrics, table, rt6_flags;
4632 struct nlmsghdr *nlh;
4633 struct rtmsg *rtm;
4634 long expires = 0;
4635
4636 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
4637 if (!nlh)
4638 return -EMSGSIZE;
4639
4640 if (rt6) {
4641 rt6_dst = &rt6->rt6i_dst;
4642 rt6_src = &rt6->rt6i_src;
4643 rt6_flags = rt6->rt6i_flags;
4644 } else {
4645 rt6_dst = &rt->fib6_dst;
4646 rt6_src = &rt->fib6_src;
4647 rt6_flags = rt->fib6_flags;
4648 }
4649
4650 rtm = nlmsg_data(nlh);
4651 rtm->rtm_family = AF_INET6;
4652 rtm->rtm_dst_len = rt6_dst->plen;
4653 rtm->rtm_src_len = rt6_src->plen;
4654 rtm->rtm_tos = 0;
4655 if (rt->fib6_table)
4656 table = rt->fib6_table->tb6_id;
4657 else
4658 table = RT6_TABLE_UNSPEC;
4659 rtm->rtm_table = table;
4660 if (nla_put_u32(skb, RTA_TABLE, table))
4661 goto nla_put_failure;
4662
4663 rtm->rtm_type = rt->fib6_type;
4664 rtm->rtm_flags = 0;
4665 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
4666 rtm->rtm_protocol = rt->fib6_protocol;
4667
4668 if (rt6_flags & RTF_CACHE)
4669 rtm->rtm_flags |= RTM_F_CLONED;
4670
4671 if (dest) {
4672 if (nla_put_in6_addr(skb, RTA_DST, dest))
4673 goto nla_put_failure;
4674 rtm->rtm_dst_len = 128;
4675 } else if (rtm->rtm_dst_len)
4676 if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr))
4677 goto nla_put_failure;
4678 #ifdef CONFIG_IPV6_SUBTREES
4679 if (src) {
4680 if (nla_put_in6_addr(skb, RTA_SRC, src))
4681 goto nla_put_failure;
4682 rtm->rtm_src_len = 128;
4683 } else if (rtm->rtm_src_len &&
4684 nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
4685 goto nla_put_failure;
4686 #endif
4687 if (iif) {
4688 #ifdef CONFIG_IPV6_MROUTE
4689 if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
4690 int err = ip6mr_get_route(net, skb, rtm, portid);
4691
4692 if (err == 0)
4693 return 0;
4694 if (err < 0)
4695 goto nla_put_failure;
4696 } else
4697 #endif
4698 if (nla_put_u32(skb, RTA_IIF, iif))
4699 goto nla_put_failure;
4700 } else if (dest) {
4701 struct in6_addr saddr_buf;
4702 if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 &&
4703 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
4704 goto nla_put_failure;
4705 }
4706
4707 if (rt->fib6_prefsrc.plen) {
4708 struct in6_addr saddr_buf;
4709 saddr_buf = rt->fib6_prefsrc.addr;
4710 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
4711 goto nla_put_failure;
4712 }
4713
4714 pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics;
4715 if (rtnetlink_put_metrics(skb, pmetrics) < 0)
4716 goto nla_put_failure;
4717
4718 if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric))
4719 goto nla_put_failure;
4720
4721 /* For multipath routes, walk the siblings list and add
4722 * each as a nexthop within RTA_MULTIPATH.
4723 */
4724 if (rt6) {
4725 if (rt6_flags & RTF_GATEWAY &&
4726 nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
4727 goto nla_put_failure;
4728
4729 if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
4730 goto nla_put_failure;
4731 } else if (rt->fib6_nsiblings) {
4732 struct fib6_info *sibling, *next_sibling;
4733 struct nlattr *mp;
4734
4735 mp = nla_nest_start(skb, RTA_MULTIPATH);
4736 if (!mp)
4737 goto nla_put_failure;
4738
4739 if (rt6_add_nexthop(skb, rt) < 0)
4740 goto nla_put_failure;
4741
4742 list_for_each_entry_safe(sibling, next_sibling,
4743 &rt->fib6_siblings, fib6_siblings) {
4744 if (rt6_add_nexthop(skb, sibling) < 0)
4745 goto nla_put_failure;
4746 }
4747
4748 nla_nest_end(skb, mp);
4749 } else {
4750 if (rt6_nexthop_info(skb, rt, &rtm->rtm_flags, false) < 0)
4751 goto nla_put_failure;
4752 }
4753
4754 if (rt6_flags & RTF_EXPIRES) {
4755 expires = dst ? dst->expires : rt->expires;
4756 expires -= jiffies;
4757 }
4758
4759 if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
4760 goto nla_put_failure;
4761
4762 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
4763 goto nla_put_failure;
4764
4765
4766 nlmsg_end(skb, nlh);
4767 return 0;
4768
4769 nla_put_failure:
4770 nlmsg_cancel(skb, nlh);
4771 return -EMSGSIZE;
4772 }
4773
4774 static bool fib6_info_uses_dev(const struct fib6_info *f6i,
4775 const struct net_device *dev)
4776 {
4777 if (f6i->fib6_nh.nh_dev == dev)
4778 return true;
4779
4780 if (f6i->fib6_nsiblings) {
4781 struct fib6_info *sibling, *next_sibling;
4782
4783 list_for_each_entry_safe(sibling, next_sibling,
4784 &f6i->fib6_siblings, fib6_siblings) {
4785 if (sibling->fib6_nh.nh_dev == dev)
4786 return true;
4787 }
4788 }
4789
4790 return false;
4791 }
4792
4793 int rt6_dump_route(struct fib6_info *rt, void *p_arg)
4794 {
4795 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
4796 struct fib_dump_filter *filter = &arg->filter;
4797 unsigned int flags = NLM_F_MULTI;
4798 struct net *net = arg->net;
4799
4800 if (rt == net->ipv6.fib6_null_entry)
4801 return 0;
4802
4803 if ((filter->flags & RTM_F_PREFIX) &&
4804 !(rt->fib6_flags & RTF_PREFIX_RT)) {
4805 /* success since this is not a prefix route */
4806 return 1;
4807 }
4808 if (filter->filter_set) {
4809 if ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
4810 (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
4811 (filter->protocol && rt->fib6_protocol != filter->protocol)) {
4812 return 1;
4813 }
4814 flags |= NLM_F_DUMP_FILTERED;
4815 }
4816
4817 return rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL, 0,
4818 RTM_NEWROUTE, NETLINK_CB(arg->cb->skb).portid,
4819 arg->cb->nlh->nlmsg_seq, flags);
4820 }
4821
4822 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4823 struct netlink_ext_ack *extack)
4824 {
4825 struct net *net = sock_net(in_skb->sk);
4826 struct nlattr *tb[RTA_MAX+1];
4827 int err, iif = 0, oif = 0;
4828 struct fib6_info *from;
4829 struct dst_entry *dst;
4830 struct rt6_info *rt;
4831 struct sk_buff *skb;
4832 struct rtmsg *rtm;
4833 struct flowi6 fl6 = {};
4834 bool fibmatch;
4835
4836 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy,
4837 extack);
4838 if (err < 0)
4839 goto errout;
4840
4841 err = -EINVAL;
4842 rtm = nlmsg_data(nlh);
4843 fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
4844 fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH);
4845
4846 if (tb[RTA_SRC]) {
4847 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
4848 goto errout;
4849
4850 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
4851 }
4852
4853 if (tb[RTA_DST]) {
4854 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
4855 goto errout;
4856
4857 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
4858 }
4859
4860 if (tb[RTA_IIF])
4861 iif = nla_get_u32(tb[RTA_IIF]);
4862
4863 if (tb[RTA_OIF])
4864 oif = nla_get_u32(tb[RTA_OIF]);
4865
4866 if (tb[RTA_MARK])
4867 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
4868
4869 if (tb[RTA_UID])
4870 fl6.flowi6_uid = make_kuid(current_user_ns(),
4871 nla_get_u32(tb[RTA_UID]));
4872 else
4873 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
4874
4875 if (tb[RTA_SPORT])
4876 fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
4877
4878 if (tb[RTA_DPORT])
4879 fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
4880
4881 if (tb[RTA_IP_PROTO]) {
4882 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
4883 &fl6.flowi6_proto, extack);
4884 if (err)
4885 goto errout;
4886 }
4887
4888 if (iif) {
4889 struct net_device *dev;
4890 int flags = 0;
4891
4892 rcu_read_lock();
4893
4894 dev = dev_get_by_index_rcu(net, iif);
4895 if (!dev) {
4896 rcu_read_unlock();
4897 err = -ENODEV;
4898 goto errout;
4899 }
4900
4901 fl6.flowi6_iif = iif;
4902
4903 if (!ipv6_addr_any(&fl6.saddr))
4904 flags |= RT6_LOOKUP_F_HAS_SADDR;
4905
4906 dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
4907
4908 rcu_read_unlock();
4909 } else {
4910 fl6.flowi6_oif = oif;
4911
4912 dst = ip6_route_output(net, NULL, &fl6);
4913 }
4914
4915
4916 rt = container_of(dst, struct rt6_info, dst);
4917 if (rt->dst.error) {
4918 err = rt->dst.error;
4919 ip6_rt_put(rt);
4920 goto errout;
4921 }
4922
4923 if (rt == net->ipv6.ip6_null_entry) {
4924 err = rt->dst.error;
4925 ip6_rt_put(rt);
4926 goto errout;
4927 }
4928
4929 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
4930 if (!skb) {
4931 ip6_rt_put(rt);
4932 err = -ENOBUFS;
4933 goto errout;
4934 }
4935
4936 skb_dst_set(skb, &rt->dst);
4937
4938 rcu_read_lock();
4939 from = rcu_dereference(rt->from);
4940
4941 if (fibmatch)
4942 err = rt6_fill_node(net, skb, from, NULL, NULL, NULL, iif,
4943 RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
4944 nlh->nlmsg_seq, 0);
4945 else
4946 err = rt6_fill_node(net, skb, from, dst, &fl6.daddr,
4947 &fl6.saddr, iif, RTM_NEWROUTE,
4948 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
4949 0);
4950 rcu_read_unlock();
4951
4952 if (err < 0) {
4953 kfree_skb(skb);
4954 goto errout;
4955 }
4956
4957 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4958 errout:
4959 return err;
4960 }
4961
4962 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
4963 unsigned int nlm_flags)
4964 {
4965 struct sk_buff *skb;
4966 struct net *net = info->nl_net;
4967 u32 seq;
4968 int err;
4969
4970 err = -ENOBUFS;
4971 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
4972
4973 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
4974 if (!skb)
4975 goto errout;
4976
4977 err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
4978 event, info->portid, seq, nlm_flags);
4979 if (err < 0) {
4980 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
4981 WARN_ON(err == -EMSGSIZE);
4982 kfree_skb(skb);
4983 goto errout;
4984 }
4985 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
4986 info->nlh, gfp_any());
4987 return;
4988 errout:
4989 if (err < 0)
4990 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
4991 }
4992
4993 static int ip6_route_dev_notify(struct notifier_block *this,
4994 unsigned long event, void *ptr)
4995 {
4996 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
4997 struct net *net = dev_net(dev);
4998
4999 if (!(dev->flags & IFF_LOOPBACK))
5000 return NOTIFY_OK;
5001
5002 if (event == NETDEV_REGISTER) {
5003 net->ipv6.fib6_null_entry->fib6_nh.nh_dev = dev;
5004 net->ipv6.ip6_null_entry->dst.dev = dev;
5005 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
5006 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5007 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
5008 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
5009 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
5010 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
5011 #endif
5012 } else if (event == NETDEV_UNREGISTER &&
5013 dev->reg_state != NETREG_UNREGISTERED) {
5014 /* NETDEV_UNREGISTER could be fired for multiple times by
5015 * netdev_wait_allrefs(). Make sure we only call this once.
5016 */
5017 in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
5018 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5019 in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
5020 in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
5021 #endif
5022 }
5023
5024 return NOTIFY_OK;
5025 }
5026
5027 /*
5028 * /proc
5029 */
5030
5031 #ifdef CONFIG_PROC_FS
5032 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
5033 {
5034 struct net *net = (struct net *)seq->private;
5035 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
5036 net->ipv6.rt6_stats->fib_nodes,
5037 net->ipv6.rt6_stats->fib_route_nodes,
5038 atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
5039 net->ipv6.rt6_stats->fib_rt_entries,
5040 net->ipv6.rt6_stats->fib_rt_cache,
5041 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
5042 net->ipv6.rt6_stats->fib_discarded_routes);
5043
5044 return 0;
5045 }
5046 #endif /* CONFIG_PROC_FS */
5047
5048 #ifdef CONFIG_SYSCTL
5049
5050 static
5051 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
5052 void __user *buffer, size_t *lenp, loff_t *ppos)
5053 {
5054 struct net *net;
5055 int delay;
5056 if (!write)
5057 return -EINVAL;
5058
5059 net = (struct net *)ctl->extra1;
5060 delay = net->ipv6.sysctl.flush_delay;
5061 proc_dointvec(ctl, write, buffer, lenp, ppos);
5062 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
5063 return 0;
5064 }
5065
5066 static int zero;
5067 static int one = 1;
5068
5069 static struct ctl_table ipv6_route_table_template[] = {
5070 {
5071 .procname = "flush",
5072 .data = &init_net.ipv6.sysctl.flush_delay,
5073 .maxlen = sizeof(int),
5074 .mode = 0200,
5075 .proc_handler = ipv6_sysctl_rtcache_flush
5076 },
5077 {
5078 .procname = "gc_thresh",
5079 .data = &ip6_dst_ops_template.gc_thresh,
5080 .maxlen = sizeof(int),
5081 .mode = 0644,
5082 .proc_handler = proc_dointvec,
5083 },
5084 {
5085 .procname = "max_size",
5086 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
5087 .maxlen = sizeof(int),
5088 .mode = 0644,
5089 .proc_handler = proc_dointvec,
5090 },
5091 {
5092 .procname = "gc_min_interval",
5093 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
5094 .maxlen = sizeof(int),
5095 .mode = 0644,
5096 .proc_handler = proc_dointvec_jiffies,
5097 },
5098 {
5099 .procname = "gc_timeout",
5100 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
5101 .maxlen = sizeof(int),
5102 .mode = 0644,
5103 .proc_handler = proc_dointvec_jiffies,
5104 },
5105 {
5106 .procname = "gc_interval",
5107 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
5108 .maxlen = sizeof(int),
5109 .mode = 0644,
5110 .proc_handler = proc_dointvec_jiffies,
5111 },
5112 {
5113 .procname = "gc_elasticity",
5114 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
5115 .maxlen = sizeof(int),
5116 .mode = 0644,
5117 .proc_handler = proc_dointvec,
5118 },
5119 {
5120 .procname = "mtu_expires",
5121 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
5122 .maxlen = sizeof(int),
5123 .mode = 0644,
5124 .proc_handler = proc_dointvec_jiffies,
5125 },
5126 {
5127 .procname = "min_adv_mss",
5128 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
5129 .maxlen = sizeof(int),
5130 .mode = 0644,
5131 .proc_handler = proc_dointvec,
5132 },
5133 {
5134 .procname = "gc_min_interval_ms",
5135 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
5136 .maxlen = sizeof(int),
5137 .mode = 0644,
5138 .proc_handler = proc_dointvec_ms_jiffies,
5139 },
5140 {
5141 .procname = "skip_notify_on_dev_down",
5142 .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down,
5143 .maxlen = sizeof(int),
5144 .mode = 0644,
5145 .proc_handler = proc_dointvec,
5146 .extra1 = &zero,
5147 .extra2 = &one,
5148 },
5149 { }
5150 };
5151
5152 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
5153 {
5154 struct ctl_table *table;
5155
5156 table = kmemdup(ipv6_route_table_template,
5157 sizeof(ipv6_route_table_template),
5158 GFP_KERNEL);
5159
5160 if (table) {
5161 table[0].data = &net->ipv6.sysctl.flush_delay;
5162 table[0].extra1 = net;
5163 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
5164 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
5165 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
5166 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
5167 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
5168 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
5169 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
5170 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
5171 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
5172 table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
5173
5174 /* Don't export sysctls to unprivileged users */
5175 if (net->user_ns != &init_user_ns)
5176 table[0].procname = NULL;
5177 }
5178
5179 return table;
5180 }
5181 #endif
5182
5183 static int __net_init ip6_route_net_init(struct net *net)
5184 {
5185 int ret = -ENOMEM;
5186
5187 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
5188 sizeof(net->ipv6.ip6_dst_ops));
5189
5190 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
5191 goto out_ip6_dst_ops;
5192
5193 net->ipv6.fib6_null_entry = kmemdup(&fib6_null_entry_template,
5194 sizeof(*net->ipv6.fib6_null_entry),
5195 GFP_KERNEL);
5196 if (!net->ipv6.fib6_null_entry)
5197 goto out_ip6_dst_entries;
5198
5199 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
5200 sizeof(*net->ipv6.ip6_null_entry),
5201 GFP_KERNEL);
5202 if (!net->ipv6.ip6_null_entry)
5203 goto out_fib6_null_entry;
5204 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
5205 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
5206 ip6_template_metrics, true);
5207
5208 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5209 net->ipv6.fib6_has_custom_rules = false;
5210 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
5211 sizeof(*net->ipv6.ip6_prohibit_entry),
5212 GFP_KERNEL);
5213 if (!net->ipv6.ip6_prohibit_entry)
5214 goto out_ip6_null_entry;
5215 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
5216 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
5217 ip6_template_metrics, true);
5218
5219 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
5220 sizeof(*net->ipv6.ip6_blk_hole_entry),
5221 GFP_KERNEL);
5222 if (!net->ipv6.ip6_blk_hole_entry)
5223 goto out_ip6_prohibit_entry;
5224 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
5225 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
5226 ip6_template_metrics, true);
5227 #endif
5228
5229 net->ipv6.sysctl.flush_delay = 0;
5230 net->ipv6.sysctl.ip6_rt_max_size = 4096;
5231 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
5232 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
5233 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
5234 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
5235 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
5236 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
5237 net->ipv6.sysctl.skip_notify_on_dev_down = 0;
5238
5239 net->ipv6.ip6_rt_gc_expire = 30*HZ;
5240
5241 ret = 0;
5242 out:
5243 return ret;
5244
5245 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5246 out_ip6_prohibit_entry:
5247 kfree(net->ipv6.ip6_prohibit_entry);
5248 out_ip6_null_entry:
5249 kfree(net->ipv6.ip6_null_entry);
5250 #endif
5251 out_fib6_null_entry:
5252 kfree(net->ipv6.fib6_null_entry);
5253 out_ip6_dst_entries:
5254 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
5255 out_ip6_dst_ops:
5256 goto out;
5257 }
5258
5259 static void __net_exit ip6_route_net_exit(struct net *net)
5260 {
5261 kfree(net->ipv6.fib6_null_entry);
5262 kfree(net->ipv6.ip6_null_entry);
5263 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5264 kfree(net->ipv6.ip6_prohibit_entry);
5265 kfree(net->ipv6.ip6_blk_hole_entry);
5266 #endif
5267 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
5268 }
5269
5270 static int __net_init ip6_route_net_init_late(struct net *net)
5271 {
5272 #ifdef CONFIG_PROC_FS
5273 proc_create_net("ipv6_route", 0, net->proc_net, &ipv6_route_seq_ops,
5274 sizeof(struct ipv6_route_iter));
5275 proc_create_net_single("rt6_stats", 0444, net->proc_net,
5276 rt6_stats_seq_show, NULL);
5277 #endif
5278 return 0;
5279 }
5280
5281 static void __net_exit ip6_route_net_exit_late(struct net *net)
5282 {
5283 #ifdef CONFIG_PROC_FS
5284 remove_proc_entry("ipv6_route", net->proc_net);
5285 remove_proc_entry("rt6_stats", net->proc_net);
5286 #endif
5287 }
5288
5289 static struct pernet_operations ip6_route_net_ops = {
5290 .init = ip6_route_net_init,
5291 .exit = ip6_route_net_exit,
5292 };
5293
5294 static int __net_init ipv6_inetpeer_init(struct net *net)
5295 {
5296 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
5297
5298 if (!bp)
5299 return -ENOMEM;
5300 inet_peer_base_init(bp);
5301 net->ipv6.peers = bp;
5302 return 0;
5303 }
5304
5305 static void __net_exit ipv6_inetpeer_exit(struct net *net)
5306 {
5307 struct inet_peer_base *bp = net->ipv6.peers;
5308
5309 net->ipv6.peers = NULL;
5310 inetpeer_invalidate_tree(bp);
5311 kfree(bp);
5312 }
5313
5314 static struct pernet_operations ipv6_inetpeer_ops = {
5315 .init = ipv6_inetpeer_init,
5316 .exit = ipv6_inetpeer_exit,
5317 };
5318
5319 static struct pernet_operations ip6_route_net_late_ops = {
5320 .init = ip6_route_net_init_late,
5321 .exit = ip6_route_net_exit_late,
5322 };
5323
5324 static struct notifier_block ip6_route_dev_notifier = {
5325 .notifier_call = ip6_route_dev_notify,
5326 .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
5327 };
5328
5329 void __init ip6_route_init_special_entries(void)
5330 {
5331 /* Registering of the loopback is done before this portion of code,
5332 * the loopback reference in rt6_info will not be taken, do it
5333 * manually for init_net */
5334 init_net.ipv6.fib6_null_entry->fib6_nh.nh_dev = init_net.loopback_dev;
5335 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
5336 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
5337 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
5338 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
5339 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
5340 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
5341 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
5342 #endif
5343 }
5344
5345 int __init ip6_route_init(void)
5346 {
5347 int ret;
5348 int cpu;
5349
5350 ret = -ENOMEM;
5351 ip6_dst_ops_template.kmem_cachep =
5352 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
5353 SLAB_HWCACHE_ALIGN, NULL);
5354 if (!ip6_dst_ops_template.kmem_cachep)
5355 goto out;
5356
5357 ret = dst_entries_init(&ip6_dst_blackhole_ops);
5358 if (ret)
5359 goto out_kmem_cache;
5360
5361 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
5362 if (ret)
5363 goto out_dst_entries;
5364
5365 ret = register_pernet_subsys(&ip6_route_net_ops);
5366 if (ret)
5367 goto out_register_inetpeer;
5368
5369 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
5370
5371 ret = fib6_init();
5372 if (ret)
5373 goto out_register_subsys;
5374
5375 ret = xfrm6_init();
5376 if (ret)
5377 goto out_fib6_init;
5378
5379 ret = fib6_rules_init();
5380 if (ret)
5381 goto xfrm6_init;
5382
5383 ret = register_pernet_subsys(&ip6_route_net_late_ops);
5384 if (ret)
5385 goto fib6_rules_init;
5386
5387 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWROUTE,
5388 inet6_rtm_newroute, NULL, 0);
5389 if (ret < 0)
5390 goto out_register_late_subsys;
5391
5392 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELROUTE,
5393 inet6_rtm_delroute, NULL, 0);
5394 if (ret < 0)
5395 goto out_register_late_subsys;
5396
5397 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE,
5398 inet6_rtm_getroute, NULL,
5399 RTNL_FLAG_DOIT_UNLOCKED);
5400 if (ret < 0)
5401 goto out_register_late_subsys;
5402
5403 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
5404 if (ret)
5405 goto out_register_late_subsys;
5406
5407 for_each_possible_cpu(cpu) {
5408 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
5409
5410 INIT_LIST_HEAD(&ul->head);
5411 spin_lock_init(&ul->lock);
5412 }
5413
5414 out:
5415 return ret;
5416
5417 out_register_late_subsys:
5418 rtnl_unregister_all(PF_INET6);
5419 unregister_pernet_subsys(&ip6_route_net_late_ops);
5420 fib6_rules_init:
5421 fib6_rules_cleanup();
5422 xfrm6_init:
5423 xfrm6_fini();
5424 out_fib6_init:
5425 fib6_gc_cleanup();
5426 out_register_subsys:
5427 unregister_pernet_subsys(&ip6_route_net_ops);
5428 out_register_inetpeer:
5429 unregister_pernet_subsys(&ipv6_inetpeer_ops);
5430 out_dst_entries:
5431 dst_entries_destroy(&ip6_dst_blackhole_ops);
5432 out_kmem_cache:
5433 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
5434 goto out;
5435 }
5436
5437 void ip6_route_cleanup(void)
5438 {
5439 unregister_netdevice_notifier(&ip6_route_dev_notifier);
5440 unregister_pernet_subsys(&ip6_route_net_late_ops);
5441 fib6_rules_cleanup();
5442 xfrm6_fini();
5443 fib6_gc_cleanup();
5444 unregister_pernet_subsys(&ipv6_inetpeer_ops);
5445 unregister_pernet_subsys(&ip6_route_net_ops);
5446 dst_entries_destroy(&ip6_dst_blackhole_ops);
5447 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
5448 }
Linux with added FPC-III support