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Merge branch 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
[deliverable/linux.git] / net / ipv6 / route.c
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 <net/net_namespace.h>
48 #include <net/snmp.h>
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ndisc.h>
53 #include <net/addrconf.h>
54 #include <net/tcp.h>
55 #include <linux/rtnetlink.h>
56 #include <net/dst.h>
57 #include <net/dst_metadata.h>
58 #include <net/xfrm.h>
59 #include <net/netevent.h>
60 #include <net/netlink.h>
61 #include <net/nexthop.h>
62 #include <net/lwtunnel.h>
63 #include <net/ip_tunnels.h>
64
65 #include <asm/uaccess.h>
66
67 #ifdef CONFIG_SYSCTL
68 #include <linux/sysctl.h>
69 #endif
70
71 enum rt6_nud_state {
72 RT6_NUD_FAIL_HARD = -3,
73 RT6_NUD_FAIL_PROBE = -2,
74 RT6_NUD_FAIL_DO_RR = -1,
75 RT6_NUD_SUCCEED = 1
76 };
77
78 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
79 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
80 static unsigned int ip6_default_advmss(const struct dst_entry *dst);
81 static unsigned int ip6_mtu(const struct dst_entry *dst);
82 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
83 static void ip6_dst_destroy(struct dst_entry *);
84 static void ip6_dst_ifdown(struct dst_entry *,
85 struct net_device *dev, int how);
86 static int ip6_dst_gc(struct dst_ops *ops);
87
88 static int ip6_pkt_discard(struct sk_buff *skb);
89 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb);
90 static int ip6_pkt_prohibit(struct sk_buff *skb);
91 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb);
92 static void ip6_link_failure(struct sk_buff *skb);
93 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
94 struct sk_buff *skb, u32 mtu);
95 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
96 struct sk_buff *skb);
97 static void rt6_dst_from_metrics_check(struct rt6_info *rt);
98 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
99
100 #ifdef CONFIG_IPV6_ROUTE_INFO
101 static struct rt6_info *rt6_add_route_info(struct net *net,
102 const struct in6_addr *prefix, int prefixlen,
103 const struct in6_addr *gwaddr, int ifindex,
104 unsigned int pref);
105 static struct rt6_info *rt6_get_route_info(struct net *net,
106 const struct in6_addr *prefix, int prefixlen,
107 const struct in6_addr *gwaddr, int ifindex);
108 #endif
109
110 struct uncached_list {
111 spinlock_t lock;
112 struct list_head head;
113 };
114
115 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
116
117 static void rt6_uncached_list_add(struct rt6_info *rt)
118 {
119 struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
120
121 rt->dst.flags |= DST_NOCACHE;
122 rt->rt6i_uncached_list = ul;
123
124 spin_lock_bh(&ul->lock);
125 list_add_tail(&rt->rt6i_uncached, &ul->head);
126 spin_unlock_bh(&ul->lock);
127 }
128
129 static void rt6_uncached_list_del(struct rt6_info *rt)
130 {
131 if (!list_empty(&rt->rt6i_uncached)) {
132 struct uncached_list *ul = rt->rt6i_uncached_list;
133
134 spin_lock_bh(&ul->lock);
135 list_del(&rt->rt6i_uncached);
136 spin_unlock_bh(&ul->lock);
137 }
138 }
139
140 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
141 {
142 struct net_device *loopback_dev = net->loopback_dev;
143 int cpu;
144
145 for_each_possible_cpu(cpu) {
146 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
147 struct rt6_info *rt;
148
149 spin_lock_bh(&ul->lock);
150 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
151 struct inet6_dev *rt_idev = rt->rt6i_idev;
152 struct net_device *rt_dev = rt->dst.dev;
153
154 if (rt_idev && (rt_idev->dev == dev || !dev) &&
155 rt_idev->dev != loopback_dev) {
156 rt->rt6i_idev = in6_dev_get(loopback_dev);
157 in6_dev_put(rt_idev);
158 }
159
160 if (rt_dev && (rt_dev == dev || !dev) &&
161 rt_dev != loopback_dev) {
162 rt->dst.dev = loopback_dev;
163 dev_hold(rt->dst.dev);
164 dev_put(rt_dev);
165 }
166 }
167 spin_unlock_bh(&ul->lock);
168 }
169 }
170
171 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
172 {
173 return dst_metrics_write_ptr(rt->dst.from);
174 }
175
176 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
177 {
178 struct rt6_info *rt = (struct rt6_info *)dst;
179
180 if (rt->rt6i_flags & RTF_PCPU)
181 return rt6_pcpu_cow_metrics(rt);
182 else if (rt->rt6i_flags & RTF_CACHE)
183 return NULL;
184 else
185 return dst_cow_metrics_generic(dst, old);
186 }
187
188 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
189 struct sk_buff *skb,
190 const void *daddr)
191 {
192 struct in6_addr *p = &rt->rt6i_gateway;
193
194 if (!ipv6_addr_any(p))
195 return (const void *) p;
196 else if (skb)
197 return &ipv6_hdr(skb)->daddr;
198 return daddr;
199 }
200
201 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
202 struct sk_buff *skb,
203 const void *daddr)
204 {
205 struct rt6_info *rt = (struct rt6_info *) dst;
206 struct neighbour *n;
207
208 daddr = choose_neigh_daddr(rt, skb, daddr);
209 n = __ipv6_neigh_lookup(dst->dev, daddr);
210 if (n)
211 return n;
212 return neigh_create(&nd_tbl, daddr, dst->dev);
213 }
214
215 static struct dst_ops ip6_dst_ops_template = {
216 .family = AF_INET6,
217 .gc = ip6_dst_gc,
218 .gc_thresh = 1024,
219 .check = ip6_dst_check,
220 .default_advmss = ip6_default_advmss,
221 .mtu = ip6_mtu,
222 .cow_metrics = ipv6_cow_metrics,
223 .destroy = ip6_dst_destroy,
224 .ifdown = ip6_dst_ifdown,
225 .negative_advice = ip6_negative_advice,
226 .link_failure = ip6_link_failure,
227 .update_pmtu = ip6_rt_update_pmtu,
228 .redirect = rt6_do_redirect,
229 .local_out = __ip6_local_out,
230 .neigh_lookup = ip6_neigh_lookup,
231 };
232
233 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
234 {
235 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
236
237 return mtu ? : dst->dev->mtu;
238 }
239
240 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
241 struct sk_buff *skb, u32 mtu)
242 {
243 }
244
245 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
246 struct sk_buff *skb)
247 {
248 }
249
250 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
251 unsigned long old)
252 {
253 return NULL;
254 }
255
256 static struct dst_ops ip6_dst_blackhole_ops = {
257 .family = AF_INET6,
258 .destroy = ip6_dst_destroy,
259 .check = ip6_dst_check,
260 .mtu = ip6_blackhole_mtu,
261 .default_advmss = ip6_default_advmss,
262 .update_pmtu = ip6_rt_blackhole_update_pmtu,
263 .redirect = ip6_rt_blackhole_redirect,
264 .cow_metrics = ip6_rt_blackhole_cow_metrics,
265 .neigh_lookup = ip6_neigh_lookup,
266 };
267
268 static const u32 ip6_template_metrics[RTAX_MAX] = {
269 [RTAX_HOPLIMIT - 1] = 0,
270 };
271
272 static const struct rt6_info ip6_null_entry_template = {
273 .dst = {
274 .__refcnt = ATOMIC_INIT(1),
275 .__use = 1,
276 .obsolete = DST_OBSOLETE_FORCE_CHK,
277 .error = -ENETUNREACH,
278 .input = ip6_pkt_discard,
279 .output = ip6_pkt_discard_out,
280 },
281 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
282 .rt6i_protocol = RTPROT_KERNEL,
283 .rt6i_metric = ~(u32) 0,
284 .rt6i_ref = ATOMIC_INIT(1),
285 };
286
287 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
288
289 static const struct rt6_info ip6_prohibit_entry_template = {
290 .dst = {
291 .__refcnt = ATOMIC_INIT(1),
292 .__use = 1,
293 .obsolete = DST_OBSOLETE_FORCE_CHK,
294 .error = -EACCES,
295 .input = ip6_pkt_prohibit,
296 .output = ip6_pkt_prohibit_out,
297 },
298 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
299 .rt6i_protocol = RTPROT_KERNEL,
300 .rt6i_metric = ~(u32) 0,
301 .rt6i_ref = ATOMIC_INIT(1),
302 };
303
304 static const struct rt6_info ip6_blk_hole_entry_template = {
305 .dst = {
306 .__refcnt = ATOMIC_INIT(1),
307 .__use = 1,
308 .obsolete = DST_OBSOLETE_FORCE_CHK,
309 .error = -EINVAL,
310 .input = dst_discard,
311 .output = dst_discard_sk,
312 },
313 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
314 .rt6i_protocol = RTPROT_KERNEL,
315 .rt6i_metric = ~(u32) 0,
316 .rt6i_ref = ATOMIC_INIT(1),
317 };
318
319 #endif
320
321 /* allocate dst with ip6_dst_ops */
322 static struct rt6_info *__ip6_dst_alloc(struct net *net,
323 struct net_device *dev,
324 int flags)
325 {
326 struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
327 0, DST_OBSOLETE_FORCE_CHK, flags);
328
329 if (rt) {
330 struct dst_entry *dst = &rt->dst;
331
332 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
333 INIT_LIST_HEAD(&rt->rt6i_siblings);
334 INIT_LIST_HEAD(&rt->rt6i_uncached);
335 }
336 return rt;
337 }
338
339 static struct rt6_info *ip6_dst_alloc(struct net *net,
340 struct net_device *dev,
341 int flags)
342 {
343 struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
344
345 if (rt) {
346 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
347 if (rt->rt6i_pcpu) {
348 int cpu;
349
350 for_each_possible_cpu(cpu) {
351 struct rt6_info **p;
352
353 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
354 /* no one shares rt */
355 *p = NULL;
356 }
357 } else {
358 dst_destroy((struct dst_entry *)rt);
359 return NULL;
360 }
361 }
362
363 return rt;
364 }
365
366 static void ip6_dst_destroy(struct dst_entry *dst)
367 {
368 struct rt6_info *rt = (struct rt6_info *)dst;
369 struct dst_entry *from = dst->from;
370 struct inet6_dev *idev;
371
372 dst_destroy_metrics_generic(dst);
373 free_percpu(rt->rt6i_pcpu);
374 rt6_uncached_list_del(rt);
375
376 idev = rt->rt6i_idev;
377 if (idev) {
378 rt->rt6i_idev = NULL;
379 in6_dev_put(idev);
380 }
381
382 dst->from = NULL;
383 dst_release(from);
384 }
385
386 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
387 int how)
388 {
389 struct rt6_info *rt = (struct rt6_info *)dst;
390 struct inet6_dev *idev = rt->rt6i_idev;
391 struct net_device *loopback_dev =
392 dev_net(dev)->loopback_dev;
393
394 if (dev != loopback_dev) {
395 if (idev && idev->dev == dev) {
396 struct inet6_dev *loopback_idev =
397 in6_dev_get(loopback_dev);
398 if (loopback_idev) {
399 rt->rt6i_idev = loopback_idev;
400 in6_dev_put(idev);
401 }
402 }
403 }
404 }
405
406 static bool rt6_check_expired(const struct rt6_info *rt)
407 {
408 if (rt->rt6i_flags & RTF_EXPIRES) {
409 if (time_after(jiffies, rt->dst.expires))
410 return true;
411 } else if (rt->dst.from) {
412 return rt6_check_expired((struct rt6_info *) rt->dst.from);
413 }
414 return false;
415 }
416
417 /* Multipath route selection:
418 * Hash based function using packet header and flowlabel.
419 * Adapted from fib_info_hashfn()
420 */
421 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
422 const struct flowi6 *fl6)
423 {
424 unsigned int val = fl6->flowi6_proto;
425
426 val ^= ipv6_addr_hash(&fl6->daddr);
427 val ^= ipv6_addr_hash(&fl6->saddr);
428
429 /* Work only if this not encapsulated */
430 switch (fl6->flowi6_proto) {
431 case IPPROTO_UDP:
432 case IPPROTO_TCP:
433 case IPPROTO_SCTP:
434 val ^= (__force u16)fl6->fl6_sport;
435 val ^= (__force u16)fl6->fl6_dport;
436 break;
437
438 case IPPROTO_ICMPV6:
439 val ^= (__force u16)fl6->fl6_icmp_type;
440 val ^= (__force u16)fl6->fl6_icmp_code;
441 break;
442 }
443 /* RFC6438 recommands to use flowlabel */
444 val ^= (__force u32)fl6->flowlabel;
445
446 /* Perhaps, we need to tune, this function? */
447 val = val ^ (val >> 7) ^ (val >> 12);
448 return val % candidate_count;
449 }
450
451 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
452 struct flowi6 *fl6, int oif,
453 int strict)
454 {
455 struct rt6_info *sibling, *next_sibling;
456 int route_choosen;
457
458 route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
459 /* Don't change the route, if route_choosen == 0
460 * (siblings does not include ourself)
461 */
462 if (route_choosen)
463 list_for_each_entry_safe(sibling, next_sibling,
464 &match->rt6i_siblings, rt6i_siblings) {
465 route_choosen--;
466 if (route_choosen == 0) {
467 if (rt6_score_route(sibling, oif, strict) < 0)
468 break;
469 match = sibling;
470 break;
471 }
472 }
473 return match;
474 }
475
476 /*
477 * Route lookup. Any table->tb6_lock is implied.
478 */
479
480 static inline struct rt6_info *rt6_device_match(struct net *net,
481 struct rt6_info *rt,
482 const struct in6_addr *saddr,
483 int oif,
484 int flags)
485 {
486 struct rt6_info *local = NULL;
487 struct rt6_info *sprt;
488
489 if (!oif && ipv6_addr_any(saddr))
490 goto out;
491
492 for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
493 struct net_device *dev = sprt->dst.dev;
494
495 if (oif) {
496 if (dev->ifindex == oif)
497 return sprt;
498 if (dev->flags & IFF_LOOPBACK) {
499 if (!sprt->rt6i_idev ||
500 sprt->rt6i_idev->dev->ifindex != oif) {
501 if (flags & RT6_LOOKUP_F_IFACE && oif)
502 continue;
503 if (local && (!oif ||
504 local->rt6i_idev->dev->ifindex == oif))
505 continue;
506 }
507 local = sprt;
508 }
509 } else {
510 if (ipv6_chk_addr(net, saddr, dev,
511 flags & RT6_LOOKUP_F_IFACE))
512 return sprt;
513 }
514 }
515
516 if (oif) {
517 if (local)
518 return local;
519
520 if (flags & RT6_LOOKUP_F_IFACE)
521 return net->ipv6.ip6_null_entry;
522 }
523 out:
524 return rt;
525 }
526
527 #ifdef CONFIG_IPV6_ROUTER_PREF
528 struct __rt6_probe_work {
529 struct work_struct work;
530 struct in6_addr target;
531 struct net_device *dev;
532 };
533
534 static void rt6_probe_deferred(struct work_struct *w)
535 {
536 struct in6_addr mcaddr;
537 struct __rt6_probe_work *work =
538 container_of(w, struct __rt6_probe_work, work);
539
540 addrconf_addr_solict_mult(&work->target, &mcaddr);
541 ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL, NULL);
542 dev_put(work->dev);
543 kfree(work);
544 }
545
546 static void rt6_probe(struct rt6_info *rt)
547 {
548 struct __rt6_probe_work *work;
549 struct neighbour *neigh;
550 /*
551 * Okay, this does not seem to be appropriate
552 * for now, however, we need to check if it
553 * is really so; aka Router Reachability Probing.
554 *
555 * Router Reachability Probe MUST be rate-limited
556 * to no more than one per minute.
557 */
558 if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
559 return;
560 rcu_read_lock_bh();
561 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
562 if (neigh) {
563 if (neigh->nud_state & NUD_VALID)
564 goto out;
565
566 work = NULL;
567 write_lock(&neigh->lock);
568 if (!(neigh->nud_state & NUD_VALID) &&
569 time_after(jiffies,
570 neigh->updated +
571 rt->rt6i_idev->cnf.rtr_probe_interval)) {
572 work = kmalloc(sizeof(*work), GFP_ATOMIC);
573 if (work)
574 __neigh_set_probe_once(neigh);
575 }
576 write_unlock(&neigh->lock);
577 } else {
578 work = kmalloc(sizeof(*work), GFP_ATOMIC);
579 }
580
581 if (work) {
582 INIT_WORK(&work->work, rt6_probe_deferred);
583 work->target = rt->rt6i_gateway;
584 dev_hold(rt->dst.dev);
585 work->dev = rt->dst.dev;
586 schedule_work(&work->work);
587 }
588
589 out:
590 rcu_read_unlock_bh();
591 }
592 #else
593 static inline void rt6_probe(struct rt6_info *rt)
594 {
595 }
596 #endif
597
598 /*
599 * Default Router Selection (RFC 2461 6.3.6)
600 */
601 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
602 {
603 struct net_device *dev = rt->dst.dev;
604 if (!oif || dev->ifindex == oif)
605 return 2;
606 if ((dev->flags & IFF_LOOPBACK) &&
607 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
608 return 1;
609 return 0;
610 }
611
612 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
613 {
614 struct neighbour *neigh;
615 enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
616
617 if (rt->rt6i_flags & RTF_NONEXTHOP ||
618 !(rt->rt6i_flags & RTF_GATEWAY))
619 return RT6_NUD_SUCCEED;
620
621 rcu_read_lock_bh();
622 neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
623 if (neigh) {
624 read_lock(&neigh->lock);
625 if (neigh->nud_state & NUD_VALID)
626 ret = RT6_NUD_SUCCEED;
627 #ifdef CONFIG_IPV6_ROUTER_PREF
628 else if (!(neigh->nud_state & NUD_FAILED))
629 ret = RT6_NUD_SUCCEED;
630 else
631 ret = RT6_NUD_FAIL_PROBE;
632 #endif
633 read_unlock(&neigh->lock);
634 } else {
635 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
636 RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
637 }
638 rcu_read_unlock_bh();
639
640 return ret;
641 }
642
643 static int rt6_score_route(struct rt6_info *rt, int oif,
644 int strict)
645 {
646 int m;
647
648 m = rt6_check_dev(rt, oif);
649 if (!m && (strict & RT6_LOOKUP_F_IFACE))
650 return RT6_NUD_FAIL_HARD;
651 #ifdef CONFIG_IPV6_ROUTER_PREF
652 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
653 #endif
654 if (strict & RT6_LOOKUP_F_REACHABLE) {
655 int n = rt6_check_neigh(rt);
656 if (n < 0)
657 return n;
658 }
659 return m;
660 }
661
662 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
663 int *mpri, struct rt6_info *match,
664 bool *do_rr)
665 {
666 int m;
667 bool match_do_rr = false;
668 struct inet6_dev *idev = rt->rt6i_idev;
669 struct net_device *dev = rt->dst.dev;
670
671 if (dev && !netif_carrier_ok(dev) &&
672 idev->cnf.ignore_routes_with_linkdown)
673 goto out;
674
675 if (rt6_check_expired(rt))
676 goto out;
677
678 m = rt6_score_route(rt, oif, strict);
679 if (m == RT6_NUD_FAIL_DO_RR) {
680 match_do_rr = true;
681 m = 0; /* lowest valid score */
682 } else if (m == RT6_NUD_FAIL_HARD) {
683 goto out;
684 }
685
686 if (strict & RT6_LOOKUP_F_REACHABLE)
687 rt6_probe(rt);
688
689 /* note that m can be RT6_NUD_FAIL_PROBE at this point */
690 if (m > *mpri) {
691 *do_rr = match_do_rr;
692 *mpri = m;
693 match = rt;
694 }
695 out:
696 return match;
697 }
698
699 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
700 struct rt6_info *rr_head,
701 u32 metric, int oif, int strict,
702 bool *do_rr)
703 {
704 struct rt6_info *rt, *match, *cont;
705 int mpri = -1;
706
707 match = NULL;
708 cont = NULL;
709 for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
710 if (rt->rt6i_metric != metric) {
711 cont = rt;
712 break;
713 }
714
715 match = find_match(rt, oif, strict, &mpri, match, do_rr);
716 }
717
718 for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
719 if (rt->rt6i_metric != metric) {
720 cont = rt;
721 break;
722 }
723
724 match = find_match(rt, oif, strict, &mpri, match, do_rr);
725 }
726
727 if (match || !cont)
728 return match;
729
730 for (rt = cont; rt; rt = rt->dst.rt6_next)
731 match = find_match(rt, oif, strict, &mpri, match, do_rr);
732
733 return match;
734 }
735
736 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
737 {
738 struct rt6_info *match, *rt0;
739 struct net *net;
740 bool do_rr = false;
741
742 rt0 = fn->rr_ptr;
743 if (!rt0)
744 fn->rr_ptr = rt0 = fn->leaf;
745
746 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
747 &do_rr);
748
749 if (do_rr) {
750 struct rt6_info *next = rt0->dst.rt6_next;
751
752 /* no entries matched; do round-robin */
753 if (!next || next->rt6i_metric != rt0->rt6i_metric)
754 next = fn->leaf;
755
756 if (next != rt0)
757 fn->rr_ptr = next;
758 }
759
760 net = dev_net(rt0->dst.dev);
761 return match ? match : net->ipv6.ip6_null_entry;
762 }
763
764 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
765 {
766 return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
767 }
768
769 #ifdef CONFIG_IPV6_ROUTE_INFO
770 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
771 const struct in6_addr *gwaddr)
772 {
773 struct net *net = dev_net(dev);
774 struct route_info *rinfo = (struct route_info *) opt;
775 struct in6_addr prefix_buf, *prefix;
776 unsigned int pref;
777 unsigned long lifetime;
778 struct rt6_info *rt;
779
780 if (len < sizeof(struct route_info)) {
781 return -EINVAL;
782 }
783
784 /* Sanity check for prefix_len and length */
785 if (rinfo->length > 3) {
786 return -EINVAL;
787 } else if (rinfo->prefix_len > 128) {
788 return -EINVAL;
789 } else if (rinfo->prefix_len > 64) {
790 if (rinfo->length < 2) {
791 return -EINVAL;
792 }
793 } else if (rinfo->prefix_len > 0) {
794 if (rinfo->length < 1) {
795 return -EINVAL;
796 }
797 }
798
799 pref = rinfo->route_pref;
800 if (pref == ICMPV6_ROUTER_PREF_INVALID)
801 return -EINVAL;
802
803 lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
804
805 if (rinfo->length == 3)
806 prefix = (struct in6_addr *)rinfo->prefix;
807 else {
808 /* this function is safe */
809 ipv6_addr_prefix(&prefix_buf,
810 (struct in6_addr *)rinfo->prefix,
811 rinfo->prefix_len);
812 prefix = &prefix_buf;
813 }
814
815 if (rinfo->prefix_len == 0)
816 rt = rt6_get_dflt_router(gwaddr, dev);
817 else
818 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
819 gwaddr, dev->ifindex);
820
821 if (rt && !lifetime) {
822 ip6_del_rt(rt);
823 rt = NULL;
824 }
825
826 if (!rt && lifetime)
827 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
828 pref);
829 else if (rt)
830 rt->rt6i_flags = RTF_ROUTEINFO |
831 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
832
833 if (rt) {
834 if (!addrconf_finite_timeout(lifetime))
835 rt6_clean_expires(rt);
836 else
837 rt6_set_expires(rt, jiffies + HZ * lifetime);
838
839 ip6_rt_put(rt);
840 }
841 return 0;
842 }
843 #endif
844
845 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
846 struct in6_addr *saddr)
847 {
848 struct fib6_node *pn;
849 while (1) {
850 if (fn->fn_flags & RTN_TL_ROOT)
851 return NULL;
852 pn = fn->parent;
853 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
854 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
855 else
856 fn = pn;
857 if (fn->fn_flags & RTN_RTINFO)
858 return fn;
859 }
860 }
861
862 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
863 struct fib6_table *table,
864 struct flowi6 *fl6, int flags)
865 {
866 struct fib6_node *fn;
867 struct rt6_info *rt;
868
869 read_lock_bh(&table->tb6_lock);
870 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
871 restart:
872 rt = fn->leaf;
873 rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
874 if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
875 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
876 if (rt == net->ipv6.ip6_null_entry) {
877 fn = fib6_backtrack(fn, &fl6->saddr);
878 if (fn)
879 goto restart;
880 }
881 dst_use(&rt->dst, jiffies);
882 read_unlock_bh(&table->tb6_lock);
883 return rt;
884
885 }
886
887 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
888 int flags)
889 {
890 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
891 }
892 EXPORT_SYMBOL_GPL(ip6_route_lookup);
893
894 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
895 const struct in6_addr *saddr, int oif, int strict)
896 {
897 struct flowi6 fl6 = {
898 .flowi6_oif = oif,
899 .daddr = *daddr,
900 };
901 struct dst_entry *dst;
902 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
903
904 if (saddr) {
905 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
906 flags |= RT6_LOOKUP_F_HAS_SADDR;
907 }
908
909 dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
910 if (dst->error == 0)
911 return (struct rt6_info *) dst;
912
913 dst_release(dst);
914
915 return NULL;
916 }
917 EXPORT_SYMBOL(rt6_lookup);
918
919 /* ip6_ins_rt is called with FREE table->tb6_lock.
920 It takes new route entry, the addition fails by any reason the
921 route is freed. In any case, if caller does not hold it, it may
922 be destroyed.
923 */
924
925 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
926 struct mx6_config *mxc)
927 {
928 int err;
929 struct fib6_table *table;
930
931 table = rt->rt6i_table;
932 write_lock_bh(&table->tb6_lock);
933 err = fib6_add(&table->tb6_root, rt, info, mxc);
934 write_unlock_bh(&table->tb6_lock);
935
936 return err;
937 }
938
939 int ip6_ins_rt(struct rt6_info *rt)
940 {
941 struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
942 struct mx6_config mxc = { .mx = NULL, };
943
944 return __ip6_ins_rt(rt, &info, &mxc);
945 }
946
947 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
948 const struct in6_addr *daddr,
949 const struct in6_addr *saddr)
950 {
951 struct rt6_info *rt;
952
953 /*
954 * Clone the route.
955 */
956
957 if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
958 ort = (struct rt6_info *)ort->dst.from;
959
960 rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
961
962 if (!rt)
963 return NULL;
964
965 ip6_rt_copy_init(rt, ort);
966 rt->rt6i_flags |= RTF_CACHE;
967 rt->rt6i_metric = 0;
968 rt->dst.flags |= DST_HOST;
969 rt->rt6i_dst.addr = *daddr;
970 rt->rt6i_dst.plen = 128;
971
972 if (!rt6_is_gw_or_nonexthop(ort)) {
973 if (ort->rt6i_dst.plen != 128 &&
974 ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
975 rt->rt6i_flags |= RTF_ANYCAST;
976 #ifdef CONFIG_IPV6_SUBTREES
977 if (rt->rt6i_src.plen && saddr) {
978 rt->rt6i_src.addr = *saddr;
979 rt->rt6i_src.plen = 128;
980 }
981 #endif
982 }
983
984 return rt;
985 }
986
987 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
988 {
989 struct rt6_info *pcpu_rt;
990
991 pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
992 rt->dst.dev, rt->dst.flags);
993
994 if (!pcpu_rt)
995 return NULL;
996 ip6_rt_copy_init(pcpu_rt, rt);
997 pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
998 pcpu_rt->rt6i_flags |= RTF_PCPU;
999 return pcpu_rt;
1000 }
1001
1002 /* It should be called with read_lock_bh(&tb6_lock) acquired */
1003 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
1004 {
1005 struct rt6_info *pcpu_rt, **p;
1006
1007 p = this_cpu_ptr(rt->rt6i_pcpu);
1008 pcpu_rt = *p;
1009
1010 if (pcpu_rt) {
1011 dst_hold(&pcpu_rt->dst);
1012 rt6_dst_from_metrics_check(pcpu_rt);
1013 }
1014 return pcpu_rt;
1015 }
1016
1017 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1018 {
1019 struct fib6_table *table = rt->rt6i_table;
1020 struct rt6_info *pcpu_rt, *prev, **p;
1021
1022 pcpu_rt = ip6_rt_pcpu_alloc(rt);
1023 if (!pcpu_rt) {
1024 struct net *net = dev_net(rt->dst.dev);
1025
1026 dst_hold(&net->ipv6.ip6_null_entry->dst);
1027 return net->ipv6.ip6_null_entry;
1028 }
1029
1030 read_lock_bh(&table->tb6_lock);
1031 if (rt->rt6i_pcpu) {
1032 p = this_cpu_ptr(rt->rt6i_pcpu);
1033 prev = cmpxchg(p, NULL, pcpu_rt);
1034 if (prev) {
1035 /* If someone did it before us, return prev instead */
1036 dst_destroy(&pcpu_rt->dst);
1037 pcpu_rt = prev;
1038 }
1039 } else {
1040 /* rt has been removed from the fib6 tree
1041 * before we have a chance to acquire the read_lock.
1042 * In this case, don't brother to create a pcpu rt
1043 * since rt is going away anyway. The next
1044 * dst_check() will trigger a re-lookup.
1045 */
1046 dst_destroy(&pcpu_rt->dst);
1047 pcpu_rt = rt;
1048 }
1049 dst_hold(&pcpu_rt->dst);
1050 rt6_dst_from_metrics_check(pcpu_rt);
1051 read_unlock_bh(&table->tb6_lock);
1052 return pcpu_rt;
1053 }
1054
1055 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1056 struct flowi6 *fl6, int flags)
1057 {
1058 struct fib6_node *fn, *saved_fn;
1059 struct rt6_info *rt;
1060 int strict = 0;
1061
1062 strict |= flags & RT6_LOOKUP_F_IFACE;
1063 if (net->ipv6.devconf_all->forwarding == 0)
1064 strict |= RT6_LOOKUP_F_REACHABLE;
1065
1066 read_lock_bh(&table->tb6_lock);
1067
1068 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1069 saved_fn = fn;
1070
1071 redo_rt6_select:
1072 rt = rt6_select(fn, oif, strict);
1073 if (rt->rt6i_nsiblings)
1074 rt = rt6_multipath_select(rt, fl6, oif, strict);
1075 if (rt == net->ipv6.ip6_null_entry) {
1076 fn = fib6_backtrack(fn, &fl6->saddr);
1077 if (fn)
1078 goto redo_rt6_select;
1079 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1080 /* also consider unreachable route */
1081 strict &= ~RT6_LOOKUP_F_REACHABLE;
1082 fn = saved_fn;
1083 goto redo_rt6_select;
1084 }
1085 }
1086
1087
1088 if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1089 dst_use(&rt->dst, jiffies);
1090 read_unlock_bh(&table->tb6_lock);
1091
1092 rt6_dst_from_metrics_check(rt);
1093 return rt;
1094 } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1095 !(rt->rt6i_flags & RTF_GATEWAY))) {
1096 /* Create a RTF_CACHE clone which will not be
1097 * owned by the fib6 tree. It is for the special case where
1098 * the daddr in the skb during the neighbor look-up is different
1099 * from the fl6->daddr used to look-up route here.
1100 */
1101
1102 struct rt6_info *uncached_rt;
1103
1104 dst_use(&rt->dst, jiffies);
1105 read_unlock_bh(&table->tb6_lock);
1106
1107 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1108 dst_release(&rt->dst);
1109
1110 if (uncached_rt)
1111 rt6_uncached_list_add(uncached_rt);
1112 else
1113 uncached_rt = net->ipv6.ip6_null_entry;
1114
1115 dst_hold(&uncached_rt->dst);
1116 return uncached_rt;
1117
1118 } else {
1119 /* Get a percpu copy */
1120
1121 struct rt6_info *pcpu_rt;
1122
1123 rt->dst.lastuse = jiffies;
1124 rt->dst.__use++;
1125 pcpu_rt = rt6_get_pcpu_route(rt);
1126
1127 if (pcpu_rt) {
1128 read_unlock_bh(&table->tb6_lock);
1129 } else {
1130 /* We have to do the read_unlock first
1131 * because rt6_make_pcpu_route() may trigger
1132 * ip6_dst_gc() which will take the write_lock.
1133 */
1134 dst_hold(&rt->dst);
1135 read_unlock_bh(&table->tb6_lock);
1136 pcpu_rt = rt6_make_pcpu_route(rt);
1137 dst_release(&rt->dst);
1138 }
1139
1140 return pcpu_rt;
1141
1142 }
1143 }
1144
1145 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1146 struct flowi6 *fl6, int flags)
1147 {
1148 return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1149 }
1150
1151 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1152 struct net_device *dev,
1153 struct flowi6 *fl6, int flags)
1154 {
1155 if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1156 flags |= RT6_LOOKUP_F_IFACE;
1157
1158 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1159 }
1160
1161 void ip6_route_input(struct sk_buff *skb)
1162 {
1163 const struct ipv6hdr *iph = ipv6_hdr(skb);
1164 struct net *net = dev_net(skb->dev);
1165 int flags = RT6_LOOKUP_F_HAS_SADDR;
1166 struct ip_tunnel_info *tun_info;
1167 struct flowi6 fl6 = {
1168 .flowi6_iif = skb->dev->ifindex,
1169 .daddr = iph->daddr,
1170 .saddr = iph->saddr,
1171 .flowlabel = ip6_flowinfo(iph),
1172 .flowi6_mark = skb->mark,
1173 .flowi6_proto = iph->nexthdr,
1174 };
1175
1176 tun_info = skb_tunnel_info(skb);
1177 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1178 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1179 skb_dst_drop(skb);
1180 skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1181 }
1182
1183 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1184 struct flowi6 *fl6, int flags)
1185 {
1186 return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1187 }
1188
1189 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1190 struct flowi6 *fl6)
1191 {
1192 int flags = 0;
1193
1194 fl6->flowi6_iif = LOOPBACK_IFINDEX;
1195
1196 if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
1197 flags |= RT6_LOOKUP_F_IFACE;
1198
1199 if (!ipv6_addr_any(&fl6->saddr))
1200 flags |= RT6_LOOKUP_F_HAS_SADDR;
1201 else if (sk)
1202 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1203
1204 return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1205 }
1206 EXPORT_SYMBOL(ip6_route_output);
1207
1208 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1209 {
1210 struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1211 struct dst_entry *new = NULL;
1212
1213 rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1214 if (rt) {
1215 new = &rt->dst;
1216
1217 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1218
1219 new->__use = 1;
1220 new->input = dst_discard;
1221 new->output = dst_discard_sk;
1222
1223 if (dst_metrics_read_only(&ort->dst))
1224 new->_metrics = ort->dst._metrics;
1225 else
1226 dst_copy_metrics(new, &ort->dst);
1227 rt->rt6i_idev = ort->rt6i_idev;
1228 if (rt->rt6i_idev)
1229 in6_dev_hold(rt->rt6i_idev);
1230
1231 rt->rt6i_gateway = ort->rt6i_gateway;
1232 rt->rt6i_flags = ort->rt6i_flags;
1233 rt->rt6i_metric = 0;
1234
1235 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1236 #ifdef CONFIG_IPV6_SUBTREES
1237 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1238 #endif
1239
1240 dst_free(new);
1241 }
1242
1243 dst_release(dst_orig);
1244 return new ? new : ERR_PTR(-ENOMEM);
1245 }
1246
1247 /*
1248 * Destination cache support functions
1249 */
1250
1251 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1252 {
1253 if (rt->dst.from &&
1254 dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1255 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1256 }
1257
1258 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1259 {
1260 if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1261 return NULL;
1262
1263 if (rt6_check_expired(rt))
1264 return NULL;
1265
1266 return &rt->dst;
1267 }
1268
1269 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1270 {
1271 if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1272 rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1273 return &rt->dst;
1274 else
1275 return NULL;
1276 }
1277
1278 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1279 {
1280 struct rt6_info *rt;
1281
1282 rt = (struct rt6_info *) dst;
1283
1284 /* All IPV6 dsts are created with ->obsolete set to the value
1285 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1286 * into this function always.
1287 */
1288
1289 rt6_dst_from_metrics_check(rt);
1290
1291 if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1292 return rt6_dst_from_check(rt, cookie);
1293 else
1294 return rt6_check(rt, cookie);
1295 }
1296
1297 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1298 {
1299 struct rt6_info *rt = (struct rt6_info *) dst;
1300
1301 if (rt) {
1302 if (rt->rt6i_flags & RTF_CACHE) {
1303 if (rt6_check_expired(rt)) {
1304 ip6_del_rt(rt);
1305 dst = NULL;
1306 }
1307 } else {
1308 dst_release(dst);
1309 dst = NULL;
1310 }
1311 }
1312 return dst;
1313 }
1314
1315 static void ip6_link_failure(struct sk_buff *skb)
1316 {
1317 struct rt6_info *rt;
1318
1319 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1320
1321 rt = (struct rt6_info *) skb_dst(skb);
1322 if (rt) {
1323 if (rt->rt6i_flags & RTF_CACHE) {
1324 dst_hold(&rt->dst);
1325 if (ip6_del_rt(rt))
1326 dst_free(&rt->dst);
1327 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1328 rt->rt6i_node->fn_sernum = -1;
1329 }
1330 }
1331 }
1332
1333 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1334 {
1335 struct net *net = dev_net(rt->dst.dev);
1336
1337 rt->rt6i_flags |= RTF_MODIFIED;
1338 rt->rt6i_pmtu = mtu;
1339 rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1340 }
1341
1342 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1343 const struct ipv6hdr *iph, u32 mtu)
1344 {
1345 struct rt6_info *rt6 = (struct rt6_info *)dst;
1346
1347 if (rt6->rt6i_flags & RTF_LOCAL)
1348 return;
1349
1350 dst_confirm(dst);
1351 mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1352 if (mtu >= dst_mtu(dst))
1353 return;
1354
1355 if (rt6->rt6i_flags & RTF_CACHE) {
1356 rt6_do_update_pmtu(rt6, mtu);
1357 } else {
1358 const struct in6_addr *daddr, *saddr;
1359 struct rt6_info *nrt6;
1360
1361 if (iph) {
1362 daddr = &iph->daddr;
1363 saddr = &iph->saddr;
1364 } else if (sk) {
1365 daddr = &sk->sk_v6_daddr;
1366 saddr = &inet6_sk(sk)->saddr;
1367 } else {
1368 return;
1369 }
1370 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1371 if (nrt6) {
1372 rt6_do_update_pmtu(nrt6, mtu);
1373
1374 /* ip6_ins_rt(nrt6) will bump the
1375 * rt6->rt6i_node->fn_sernum
1376 * which will fail the next rt6_check() and
1377 * invalidate the sk->sk_dst_cache.
1378 */
1379 ip6_ins_rt(nrt6);
1380 }
1381 }
1382 }
1383
1384 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1385 struct sk_buff *skb, u32 mtu)
1386 {
1387 __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1388 }
1389
1390 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1391 int oif, u32 mark)
1392 {
1393 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1394 struct dst_entry *dst;
1395 struct flowi6 fl6;
1396
1397 memset(&fl6, 0, sizeof(fl6));
1398 fl6.flowi6_oif = oif;
1399 fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1400 fl6.daddr = iph->daddr;
1401 fl6.saddr = iph->saddr;
1402 fl6.flowlabel = ip6_flowinfo(iph);
1403
1404 dst = ip6_route_output(net, NULL, &fl6);
1405 if (!dst->error)
1406 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1407 dst_release(dst);
1408 }
1409 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1410
1411 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1412 {
1413 ip6_update_pmtu(skb, sock_net(sk), mtu,
1414 sk->sk_bound_dev_if, sk->sk_mark);
1415 }
1416 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1417
1418 /* Handle redirects */
1419 struct ip6rd_flowi {
1420 struct flowi6 fl6;
1421 struct in6_addr gateway;
1422 };
1423
1424 static struct rt6_info *__ip6_route_redirect(struct net *net,
1425 struct fib6_table *table,
1426 struct flowi6 *fl6,
1427 int flags)
1428 {
1429 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1430 struct rt6_info *rt;
1431 struct fib6_node *fn;
1432
1433 /* Get the "current" route for this destination and
1434 * check if the redirect has come from approriate router.
1435 *
1436 * RFC 4861 specifies that redirects should only be
1437 * accepted if they come from the nexthop to the target.
1438 * Due to the way the routes are chosen, this notion
1439 * is a bit fuzzy and one might need to check all possible
1440 * routes.
1441 */
1442
1443 read_lock_bh(&table->tb6_lock);
1444 fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1445 restart:
1446 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1447 if (rt6_check_expired(rt))
1448 continue;
1449 if (rt->dst.error)
1450 break;
1451 if (!(rt->rt6i_flags & RTF_GATEWAY))
1452 continue;
1453 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1454 continue;
1455 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1456 continue;
1457 break;
1458 }
1459
1460 if (!rt)
1461 rt = net->ipv6.ip6_null_entry;
1462 else if (rt->dst.error) {
1463 rt = net->ipv6.ip6_null_entry;
1464 goto out;
1465 }
1466
1467 if (rt == net->ipv6.ip6_null_entry) {
1468 fn = fib6_backtrack(fn, &fl6->saddr);
1469 if (fn)
1470 goto restart;
1471 }
1472
1473 out:
1474 dst_hold(&rt->dst);
1475
1476 read_unlock_bh(&table->tb6_lock);
1477
1478 return rt;
1479 };
1480
1481 static struct dst_entry *ip6_route_redirect(struct net *net,
1482 const struct flowi6 *fl6,
1483 const struct in6_addr *gateway)
1484 {
1485 int flags = RT6_LOOKUP_F_HAS_SADDR;
1486 struct ip6rd_flowi rdfl;
1487
1488 rdfl.fl6 = *fl6;
1489 rdfl.gateway = *gateway;
1490
1491 return fib6_rule_lookup(net, &rdfl.fl6,
1492 flags, __ip6_route_redirect);
1493 }
1494
1495 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1496 {
1497 const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1498 struct dst_entry *dst;
1499 struct flowi6 fl6;
1500
1501 memset(&fl6, 0, sizeof(fl6));
1502 fl6.flowi6_iif = LOOPBACK_IFINDEX;
1503 fl6.flowi6_oif = oif;
1504 fl6.flowi6_mark = mark;
1505 fl6.daddr = iph->daddr;
1506 fl6.saddr = iph->saddr;
1507 fl6.flowlabel = ip6_flowinfo(iph);
1508
1509 dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1510 rt6_do_redirect(dst, NULL, skb);
1511 dst_release(dst);
1512 }
1513 EXPORT_SYMBOL_GPL(ip6_redirect);
1514
1515 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1516 u32 mark)
1517 {
1518 const struct ipv6hdr *iph = ipv6_hdr(skb);
1519 const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1520 struct dst_entry *dst;
1521 struct flowi6 fl6;
1522
1523 memset(&fl6, 0, sizeof(fl6));
1524 fl6.flowi6_iif = LOOPBACK_IFINDEX;
1525 fl6.flowi6_oif = oif;
1526 fl6.flowi6_mark = mark;
1527 fl6.daddr = msg->dest;
1528 fl6.saddr = iph->daddr;
1529
1530 dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1531 rt6_do_redirect(dst, NULL, skb);
1532 dst_release(dst);
1533 }
1534
1535 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1536 {
1537 ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1538 }
1539 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1540
1541 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1542 {
1543 struct net_device *dev = dst->dev;
1544 unsigned int mtu = dst_mtu(dst);
1545 struct net *net = dev_net(dev);
1546
1547 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1548
1549 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1550 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1551
1552 /*
1553 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1554 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1555 * IPV6_MAXPLEN is also valid and means: "any MSS,
1556 * rely only on pmtu discovery"
1557 */
1558 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1559 mtu = IPV6_MAXPLEN;
1560 return mtu;
1561 }
1562
1563 static unsigned int ip6_mtu(const struct dst_entry *dst)
1564 {
1565 const struct rt6_info *rt = (const struct rt6_info *)dst;
1566 unsigned int mtu = rt->rt6i_pmtu;
1567 struct inet6_dev *idev;
1568
1569 if (mtu)
1570 goto out;
1571
1572 mtu = dst_metric_raw(dst, RTAX_MTU);
1573 if (mtu)
1574 goto out;
1575
1576 mtu = IPV6_MIN_MTU;
1577
1578 rcu_read_lock();
1579 idev = __in6_dev_get(dst->dev);
1580 if (idev)
1581 mtu = idev->cnf.mtu6;
1582 rcu_read_unlock();
1583
1584 out:
1585 return min_t(unsigned int, mtu, IP6_MAX_MTU);
1586 }
1587
1588 static struct dst_entry *icmp6_dst_gc_list;
1589 static DEFINE_SPINLOCK(icmp6_dst_lock);
1590
1591 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1592 struct flowi6 *fl6)
1593 {
1594 struct dst_entry *dst;
1595 struct rt6_info *rt;
1596 struct inet6_dev *idev = in6_dev_get(dev);
1597 struct net *net = dev_net(dev);
1598
1599 if (unlikely(!idev))
1600 return ERR_PTR(-ENODEV);
1601
1602 rt = ip6_dst_alloc(net, dev, 0);
1603 if (unlikely(!rt)) {
1604 in6_dev_put(idev);
1605 dst = ERR_PTR(-ENOMEM);
1606 goto out;
1607 }
1608
1609 rt->dst.flags |= DST_HOST;
1610 rt->dst.output = ip6_output;
1611 atomic_set(&rt->dst.__refcnt, 1);
1612 rt->rt6i_gateway = fl6->daddr;
1613 rt->rt6i_dst.addr = fl6->daddr;
1614 rt->rt6i_dst.plen = 128;
1615 rt->rt6i_idev = idev;
1616 dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1617
1618 spin_lock_bh(&icmp6_dst_lock);
1619 rt->dst.next = icmp6_dst_gc_list;
1620 icmp6_dst_gc_list = &rt->dst;
1621 spin_unlock_bh(&icmp6_dst_lock);
1622
1623 fib6_force_start_gc(net);
1624
1625 dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1626
1627 out:
1628 return dst;
1629 }
1630
1631 int icmp6_dst_gc(void)
1632 {
1633 struct dst_entry *dst, **pprev;
1634 int more = 0;
1635
1636 spin_lock_bh(&icmp6_dst_lock);
1637 pprev = &icmp6_dst_gc_list;
1638
1639 while ((dst = *pprev) != NULL) {
1640 if (!atomic_read(&dst->__refcnt)) {
1641 *pprev = dst->next;
1642 dst_free(dst);
1643 } else {
1644 pprev = &dst->next;
1645 ++more;
1646 }
1647 }
1648
1649 spin_unlock_bh(&icmp6_dst_lock);
1650
1651 return more;
1652 }
1653
1654 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1655 void *arg)
1656 {
1657 struct dst_entry *dst, **pprev;
1658
1659 spin_lock_bh(&icmp6_dst_lock);
1660 pprev = &icmp6_dst_gc_list;
1661 while ((dst = *pprev) != NULL) {
1662 struct rt6_info *rt = (struct rt6_info *) dst;
1663 if (func(rt, arg)) {
1664 *pprev = dst->next;
1665 dst_free(dst);
1666 } else {
1667 pprev = &dst->next;
1668 }
1669 }
1670 spin_unlock_bh(&icmp6_dst_lock);
1671 }
1672
1673 static int ip6_dst_gc(struct dst_ops *ops)
1674 {
1675 struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1676 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1677 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1678 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1679 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1680 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1681 int entries;
1682
1683 entries = dst_entries_get_fast(ops);
1684 if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1685 entries <= rt_max_size)
1686 goto out;
1687
1688 net->ipv6.ip6_rt_gc_expire++;
1689 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1690 entries = dst_entries_get_slow(ops);
1691 if (entries < ops->gc_thresh)
1692 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1693 out:
1694 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1695 return entries > rt_max_size;
1696 }
1697
1698 static int ip6_convert_metrics(struct mx6_config *mxc,
1699 const struct fib6_config *cfg)
1700 {
1701 bool ecn_ca = false;
1702 struct nlattr *nla;
1703 int remaining;
1704 u32 *mp;
1705
1706 if (!cfg->fc_mx)
1707 return 0;
1708
1709 mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1710 if (unlikely(!mp))
1711 return -ENOMEM;
1712
1713 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1714 int type = nla_type(nla);
1715 u32 val;
1716
1717 if (!type)
1718 continue;
1719 if (unlikely(type > RTAX_MAX))
1720 goto err;
1721
1722 if (type == RTAX_CC_ALGO) {
1723 char tmp[TCP_CA_NAME_MAX];
1724
1725 nla_strlcpy(tmp, nla, sizeof(tmp));
1726 val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1727 if (val == TCP_CA_UNSPEC)
1728 goto err;
1729 } else {
1730 val = nla_get_u32(nla);
1731 }
1732 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1733 goto err;
1734
1735 mp[type - 1] = val;
1736 __set_bit(type - 1, mxc->mx_valid);
1737 }
1738
1739 if (ecn_ca) {
1740 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1741 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1742 }
1743
1744 mxc->mx = mp;
1745 return 0;
1746 err:
1747 kfree(mp);
1748 return -EINVAL;
1749 }
1750
1751 int ip6_route_add(struct fib6_config *cfg)
1752 {
1753 int err;
1754 struct net *net = cfg->fc_nlinfo.nl_net;
1755 struct rt6_info *rt = NULL;
1756 struct net_device *dev = NULL;
1757 struct inet6_dev *idev = NULL;
1758 struct fib6_table *table;
1759 struct mx6_config mxc = { .mx = NULL, };
1760 int addr_type;
1761
1762 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1763 return -EINVAL;
1764 #ifndef CONFIG_IPV6_SUBTREES
1765 if (cfg->fc_src_len)
1766 return -EINVAL;
1767 #endif
1768 if (cfg->fc_ifindex) {
1769 err = -ENODEV;
1770 dev = dev_get_by_index(net, cfg->fc_ifindex);
1771 if (!dev)
1772 goto out;
1773 idev = in6_dev_get(dev);
1774 if (!idev)
1775 goto out;
1776 }
1777
1778 if (cfg->fc_metric == 0)
1779 cfg->fc_metric = IP6_RT_PRIO_USER;
1780
1781 err = -ENOBUFS;
1782 if (cfg->fc_nlinfo.nlh &&
1783 !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1784 table = fib6_get_table(net, cfg->fc_table);
1785 if (!table) {
1786 pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1787 table = fib6_new_table(net, cfg->fc_table);
1788 }
1789 } else {
1790 table = fib6_new_table(net, cfg->fc_table);
1791 }
1792
1793 if (!table)
1794 goto out;
1795
1796 rt = ip6_dst_alloc(net, NULL,
1797 (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1798
1799 if (!rt) {
1800 err = -ENOMEM;
1801 goto out;
1802 }
1803
1804 if (cfg->fc_flags & RTF_EXPIRES)
1805 rt6_set_expires(rt, jiffies +
1806 clock_t_to_jiffies(cfg->fc_expires));
1807 else
1808 rt6_clean_expires(rt);
1809
1810 if (cfg->fc_protocol == RTPROT_UNSPEC)
1811 cfg->fc_protocol = RTPROT_BOOT;
1812 rt->rt6i_protocol = cfg->fc_protocol;
1813
1814 addr_type = ipv6_addr_type(&cfg->fc_dst);
1815
1816 if (addr_type & IPV6_ADDR_MULTICAST)
1817 rt->dst.input = ip6_mc_input;
1818 else if (cfg->fc_flags & RTF_LOCAL)
1819 rt->dst.input = ip6_input;
1820 else
1821 rt->dst.input = ip6_forward;
1822
1823 rt->dst.output = ip6_output;
1824
1825 if (cfg->fc_encap) {
1826 struct lwtunnel_state *lwtstate;
1827
1828 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1829 cfg->fc_encap, AF_INET6, cfg,
1830 &lwtstate);
1831 if (err)
1832 goto out;
1833 rt->dst.lwtstate = lwtstate_get(lwtstate);
1834 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1835 rt->dst.lwtstate->orig_output = rt->dst.output;
1836 rt->dst.output = lwtunnel_output;
1837 }
1838 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1839 rt->dst.lwtstate->orig_input = rt->dst.input;
1840 rt->dst.input = lwtunnel_input;
1841 }
1842 }
1843
1844 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1845 rt->rt6i_dst.plen = cfg->fc_dst_len;
1846 if (rt->rt6i_dst.plen == 128)
1847 rt->dst.flags |= DST_HOST;
1848
1849 #ifdef CONFIG_IPV6_SUBTREES
1850 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1851 rt->rt6i_src.plen = cfg->fc_src_len;
1852 #endif
1853
1854 rt->rt6i_metric = cfg->fc_metric;
1855
1856 /* We cannot add true routes via loopback here,
1857 they would result in kernel looping; promote them to reject routes
1858 */
1859 if ((cfg->fc_flags & RTF_REJECT) ||
1860 (dev && (dev->flags & IFF_LOOPBACK) &&
1861 !(addr_type & IPV6_ADDR_LOOPBACK) &&
1862 !(cfg->fc_flags & RTF_LOCAL))) {
1863 /* hold loopback dev/idev if we haven't done so. */
1864 if (dev != net->loopback_dev) {
1865 if (dev) {
1866 dev_put(dev);
1867 in6_dev_put(idev);
1868 }
1869 dev = net->loopback_dev;
1870 dev_hold(dev);
1871 idev = in6_dev_get(dev);
1872 if (!idev) {
1873 err = -ENODEV;
1874 goto out;
1875 }
1876 }
1877 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1878 switch (cfg->fc_type) {
1879 case RTN_BLACKHOLE:
1880 rt->dst.error = -EINVAL;
1881 rt->dst.output = dst_discard_sk;
1882 rt->dst.input = dst_discard;
1883 break;
1884 case RTN_PROHIBIT:
1885 rt->dst.error = -EACCES;
1886 rt->dst.output = ip6_pkt_prohibit_out;
1887 rt->dst.input = ip6_pkt_prohibit;
1888 break;
1889 case RTN_THROW:
1890 default:
1891 rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1892 : -ENETUNREACH;
1893 rt->dst.output = ip6_pkt_discard_out;
1894 rt->dst.input = ip6_pkt_discard;
1895 break;
1896 }
1897 goto install_route;
1898 }
1899
1900 if (cfg->fc_flags & RTF_GATEWAY) {
1901 const struct in6_addr *gw_addr;
1902 int gwa_type;
1903
1904 gw_addr = &cfg->fc_gateway;
1905 gwa_type = ipv6_addr_type(gw_addr);
1906
1907 /* if gw_addr is local we will fail to detect this in case
1908 * address is still TENTATIVE (DAD in progress). rt6_lookup()
1909 * will return already-added prefix route via interface that
1910 * prefix route was assigned to, which might be non-loopback.
1911 */
1912 err = -EINVAL;
1913 if (ipv6_chk_addr_and_flags(net, gw_addr,
1914 gwa_type & IPV6_ADDR_LINKLOCAL ?
1915 dev : NULL, 0, 0))
1916 goto out;
1917
1918 rt->rt6i_gateway = *gw_addr;
1919
1920 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1921 struct rt6_info *grt;
1922
1923 /* IPv6 strictly inhibits using not link-local
1924 addresses as nexthop address.
1925 Otherwise, router will not able to send redirects.
1926 It is very good, but in some (rare!) circumstances
1927 (SIT, PtP, NBMA NOARP links) it is handy to allow
1928 some exceptions. --ANK
1929 */
1930 if (!(gwa_type & IPV6_ADDR_UNICAST))
1931 goto out;
1932
1933 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1934
1935 err = -EHOSTUNREACH;
1936 if (!grt)
1937 goto out;
1938 if (dev) {
1939 if (dev != grt->dst.dev) {
1940 ip6_rt_put(grt);
1941 goto out;
1942 }
1943 } else {
1944 dev = grt->dst.dev;
1945 idev = grt->rt6i_idev;
1946 dev_hold(dev);
1947 in6_dev_hold(grt->rt6i_idev);
1948 }
1949 if (!(grt->rt6i_flags & RTF_GATEWAY))
1950 err = 0;
1951 ip6_rt_put(grt);
1952
1953 if (err)
1954 goto out;
1955 }
1956 err = -EINVAL;
1957 if (!dev || (dev->flags & IFF_LOOPBACK))
1958 goto out;
1959 }
1960
1961 err = -ENODEV;
1962 if (!dev)
1963 goto out;
1964
1965 if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1966 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1967 err = -EINVAL;
1968 goto out;
1969 }
1970 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1971 rt->rt6i_prefsrc.plen = 128;
1972 } else
1973 rt->rt6i_prefsrc.plen = 0;
1974
1975 rt->rt6i_flags = cfg->fc_flags;
1976
1977 install_route:
1978 rt->dst.dev = dev;
1979 rt->rt6i_idev = idev;
1980 rt->rt6i_table = table;
1981
1982 cfg->fc_nlinfo.nl_net = dev_net(dev);
1983
1984 err = ip6_convert_metrics(&mxc, cfg);
1985 if (err)
1986 goto out;
1987
1988 err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
1989
1990 kfree(mxc.mx);
1991 return err;
1992 out:
1993 if (dev)
1994 dev_put(dev);
1995 if (idev)
1996 in6_dev_put(idev);
1997 if (rt)
1998 dst_free(&rt->dst);
1999 return err;
2000 }
2001
2002 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2003 {
2004 int err;
2005 struct fib6_table *table;
2006 struct net *net = dev_net(rt->dst.dev);
2007
2008 if (rt == net->ipv6.ip6_null_entry) {
2009 err = -ENOENT;
2010 goto out;
2011 }
2012
2013 table = rt->rt6i_table;
2014 write_lock_bh(&table->tb6_lock);
2015 err = fib6_del(rt, info);
2016 write_unlock_bh(&table->tb6_lock);
2017
2018 out:
2019 ip6_rt_put(rt);
2020 return err;
2021 }
2022
2023 int ip6_del_rt(struct rt6_info *rt)
2024 {
2025 struct nl_info info = {
2026 .nl_net = dev_net(rt->dst.dev),
2027 };
2028 return __ip6_del_rt(rt, &info);
2029 }
2030
2031 static int ip6_route_del(struct fib6_config *cfg)
2032 {
2033 struct fib6_table *table;
2034 struct fib6_node *fn;
2035 struct rt6_info *rt;
2036 int err = -ESRCH;
2037
2038 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2039 if (!table)
2040 return err;
2041
2042 read_lock_bh(&table->tb6_lock);
2043
2044 fn = fib6_locate(&table->tb6_root,
2045 &cfg->fc_dst, cfg->fc_dst_len,
2046 &cfg->fc_src, cfg->fc_src_len);
2047
2048 if (fn) {
2049 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2050 if ((rt->rt6i_flags & RTF_CACHE) &&
2051 !(cfg->fc_flags & RTF_CACHE))
2052 continue;
2053 if (cfg->fc_ifindex &&
2054 (!rt->dst.dev ||
2055 rt->dst.dev->ifindex != cfg->fc_ifindex))
2056 continue;
2057 if (cfg->fc_flags & RTF_GATEWAY &&
2058 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2059 continue;
2060 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2061 continue;
2062 dst_hold(&rt->dst);
2063 read_unlock_bh(&table->tb6_lock);
2064
2065 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2066 }
2067 }
2068 read_unlock_bh(&table->tb6_lock);
2069
2070 return err;
2071 }
2072
2073 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2074 {
2075 struct net *net = dev_net(skb->dev);
2076 struct netevent_redirect netevent;
2077 struct rt6_info *rt, *nrt = NULL;
2078 struct ndisc_options ndopts;
2079 struct inet6_dev *in6_dev;
2080 struct neighbour *neigh;
2081 struct rd_msg *msg;
2082 int optlen, on_link;
2083 u8 *lladdr;
2084
2085 optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2086 optlen -= sizeof(*msg);
2087
2088 if (optlen < 0) {
2089 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2090 return;
2091 }
2092
2093 msg = (struct rd_msg *)icmp6_hdr(skb);
2094
2095 if (ipv6_addr_is_multicast(&msg->dest)) {
2096 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2097 return;
2098 }
2099
2100 on_link = 0;
2101 if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2102 on_link = 1;
2103 } else if (ipv6_addr_type(&msg->target) !=
2104 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2105 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2106 return;
2107 }
2108
2109 in6_dev = __in6_dev_get(skb->dev);
2110 if (!in6_dev)
2111 return;
2112 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2113 return;
2114
2115 /* RFC2461 8.1:
2116 * The IP source address of the Redirect MUST be the same as the current
2117 * first-hop router for the specified ICMP Destination Address.
2118 */
2119
2120 if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2121 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2122 return;
2123 }
2124
2125 lladdr = NULL;
2126 if (ndopts.nd_opts_tgt_lladdr) {
2127 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2128 skb->dev);
2129 if (!lladdr) {
2130 net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2131 return;
2132 }
2133 }
2134
2135 rt = (struct rt6_info *) dst;
2136 if (rt == net->ipv6.ip6_null_entry) {
2137 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2138 return;
2139 }
2140
2141 /* Redirect received -> path was valid.
2142 * Look, redirects are sent only in response to data packets,
2143 * so that this nexthop apparently is reachable. --ANK
2144 */
2145 dst_confirm(&rt->dst);
2146
2147 neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2148 if (!neigh)
2149 return;
2150
2151 /*
2152 * We have finally decided to accept it.
2153 */
2154
2155 neigh_update(neigh, lladdr, NUD_STALE,
2156 NEIGH_UPDATE_F_WEAK_OVERRIDE|
2157 NEIGH_UPDATE_F_OVERRIDE|
2158 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2159 NEIGH_UPDATE_F_ISROUTER))
2160 );
2161
2162 nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2163 if (!nrt)
2164 goto out;
2165
2166 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2167 if (on_link)
2168 nrt->rt6i_flags &= ~RTF_GATEWAY;
2169
2170 nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2171
2172 if (ip6_ins_rt(nrt))
2173 goto out;
2174
2175 netevent.old = &rt->dst;
2176 netevent.new = &nrt->dst;
2177 netevent.daddr = &msg->dest;
2178 netevent.neigh = neigh;
2179 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2180
2181 if (rt->rt6i_flags & RTF_CACHE) {
2182 rt = (struct rt6_info *) dst_clone(&rt->dst);
2183 ip6_del_rt(rt);
2184 }
2185
2186 out:
2187 neigh_release(neigh);
2188 }
2189
2190 /*
2191 * Misc support functions
2192 */
2193
2194 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2195 {
2196 BUG_ON(from->dst.from);
2197
2198 rt->rt6i_flags &= ~RTF_EXPIRES;
2199 dst_hold(&from->dst);
2200 rt->dst.from = &from->dst;
2201 dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2202 }
2203
2204 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2205 {
2206 rt->dst.input = ort->dst.input;
2207 rt->dst.output = ort->dst.output;
2208 rt->rt6i_dst = ort->rt6i_dst;
2209 rt->dst.error = ort->dst.error;
2210 rt->rt6i_idev = ort->rt6i_idev;
2211 if (rt->rt6i_idev)
2212 in6_dev_hold(rt->rt6i_idev);
2213 rt->dst.lastuse = jiffies;
2214 rt->rt6i_gateway = ort->rt6i_gateway;
2215 rt->rt6i_flags = ort->rt6i_flags;
2216 rt6_set_from(rt, ort);
2217 rt->rt6i_metric = ort->rt6i_metric;
2218 #ifdef CONFIG_IPV6_SUBTREES
2219 rt->rt6i_src = ort->rt6i_src;
2220 #endif
2221 rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2222 rt->rt6i_table = ort->rt6i_table;
2223 rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2224 }
2225
2226 #ifdef CONFIG_IPV6_ROUTE_INFO
2227 static struct rt6_info *rt6_get_route_info(struct net *net,
2228 const struct in6_addr *prefix, int prefixlen,
2229 const struct in6_addr *gwaddr, int ifindex)
2230 {
2231 struct fib6_node *fn;
2232 struct rt6_info *rt = NULL;
2233 struct fib6_table *table;
2234
2235 table = fib6_get_table(net, RT6_TABLE_INFO);
2236 if (!table)
2237 return NULL;
2238
2239 read_lock_bh(&table->tb6_lock);
2240 fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2241 if (!fn)
2242 goto out;
2243
2244 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2245 if (rt->dst.dev->ifindex != ifindex)
2246 continue;
2247 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2248 continue;
2249 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2250 continue;
2251 dst_hold(&rt->dst);
2252 break;
2253 }
2254 out:
2255 read_unlock_bh(&table->tb6_lock);
2256 return rt;
2257 }
2258
2259 static struct rt6_info *rt6_add_route_info(struct net *net,
2260 const struct in6_addr *prefix, int prefixlen,
2261 const struct in6_addr *gwaddr, int ifindex,
2262 unsigned int pref)
2263 {
2264 struct fib6_config cfg = {
2265 .fc_table = RT6_TABLE_INFO,
2266 .fc_metric = IP6_RT_PRIO_USER,
2267 .fc_ifindex = ifindex,
2268 .fc_dst_len = prefixlen,
2269 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2270 RTF_UP | RTF_PREF(pref),
2271 .fc_nlinfo.portid = 0,
2272 .fc_nlinfo.nlh = NULL,
2273 .fc_nlinfo.nl_net = net,
2274 };
2275
2276 cfg.fc_dst = *prefix;
2277 cfg.fc_gateway = *gwaddr;
2278
2279 /* We should treat it as a default route if prefix length is 0. */
2280 if (!prefixlen)
2281 cfg.fc_flags |= RTF_DEFAULT;
2282
2283 ip6_route_add(&cfg);
2284
2285 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2286 }
2287 #endif
2288
2289 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2290 {
2291 struct rt6_info *rt;
2292 struct fib6_table *table;
2293
2294 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2295 if (!table)
2296 return NULL;
2297
2298 read_lock_bh(&table->tb6_lock);
2299 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2300 if (dev == rt->dst.dev &&
2301 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2302 ipv6_addr_equal(&rt->rt6i_gateway, addr))
2303 break;
2304 }
2305 if (rt)
2306 dst_hold(&rt->dst);
2307 read_unlock_bh(&table->tb6_lock);
2308 return rt;
2309 }
2310
2311 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2312 struct net_device *dev,
2313 unsigned int pref)
2314 {
2315 struct fib6_config cfg = {
2316 .fc_table = RT6_TABLE_DFLT,
2317 .fc_metric = IP6_RT_PRIO_USER,
2318 .fc_ifindex = dev->ifindex,
2319 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2320 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2321 .fc_nlinfo.portid = 0,
2322 .fc_nlinfo.nlh = NULL,
2323 .fc_nlinfo.nl_net = dev_net(dev),
2324 };
2325
2326 cfg.fc_gateway = *gwaddr;
2327
2328 ip6_route_add(&cfg);
2329
2330 return rt6_get_dflt_router(gwaddr, dev);
2331 }
2332
2333 void rt6_purge_dflt_routers(struct net *net)
2334 {
2335 struct rt6_info *rt;
2336 struct fib6_table *table;
2337
2338 /* NOTE: Keep consistent with rt6_get_dflt_router */
2339 table = fib6_get_table(net, RT6_TABLE_DFLT);
2340 if (!table)
2341 return;
2342
2343 restart:
2344 read_lock_bh(&table->tb6_lock);
2345 for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2346 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2347 (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2348 dst_hold(&rt->dst);
2349 read_unlock_bh(&table->tb6_lock);
2350 ip6_del_rt(rt);
2351 goto restart;
2352 }
2353 }
2354 read_unlock_bh(&table->tb6_lock);
2355 }
2356
2357 static void rtmsg_to_fib6_config(struct net *net,
2358 struct in6_rtmsg *rtmsg,
2359 struct fib6_config *cfg)
2360 {
2361 memset(cfg, 0, sizeof(*cfg));
2362
2363 cfg->fc_table = RT6_TABLE_MAIN;
2364 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2365 cfg->fc_metric = rtmsg->rtmsg_metric;
2366 cfg->fc_expires = rtmsg->rtmsg_info;
2367 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2368 cfg->fc_src_len = rtmsg->rtmsg_src_len;
2369 cfg->fc_flags = rtmsg->rtmsg_flags;
2370
2371 cfg->fc_nlinfo.nl_net = net;
2372
2373 cfg->fc_dst = rtmsg->rtmsg_dst;
2374 cfg->fc_src = rtmsg->rtmsg_src;
2375 cfg->fc_gateway = rtmsg->rtmsg_gateway;
2376 }
2377
2378 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2379 {
2380 struct fib6_config cfg;
2381 struct in6_rtmsg rtmsg;
2382 int err;
2383
2384 switch (cmd) {
2385 case SIOCADDRT: /* Add a route */
2386 case SIOCDELRT: /* Delete a route */
2387 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2388 return -EPERM;
2389 err = copy_from_user(&rtmsg, arg,
2390 sizeof(struct in6_rtmsg));
2391 if (err)
2392 return -EFAULT;
2393
2394 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2395
2396 rtnl_lock();
2397 switch (cmd) {
2398 case SIOCADDRT:
2399 err = ip6_route_add(&cfg);
2400 break;
2401 case SIOCDELRT:
2402 err = ip6_route_del(&cfg);
2403 break;
2404 default:
2405 err = -EINVAL;
2406 }
2407 rtnl_unlock();
2408
2409 return err;
2410 }
2411
2412 return -EINVAL;
2413 }
2414
2415 /*
2416 * Drop the packet on the floor
2417 */
2418
2419 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2420 {
2421 int type;
2422 struct dst_entry *dst = skb_dst(skb);
2423 switch (ipstats_mib_noroutes) {
2424 case IPSTATS_MIB_INNOROUTES:
2425 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2426 if (type == IPV6_ADDR_ANY) {
2427 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2428 IPSTATS_MIB_INADDRERRORS);
2429 break;
2430 }
2431 /* FALLTHROUGH */
2432 case IPSTATS_MIB_OUTNOROUTES:
2433 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2434 ipstats_mib_noroutes);
2435 break;
2436 }
2437 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2438 kfree_skb(skb);
2439 return 0;
2440 }
2441
2442 static int ip6_pkt_discard(struct sk_buff *skb)
2443 {
2444 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2445 }
2446
2447 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2448 {
2449 skb->dev = skb_dst(skb)->dev;
2450 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2451 }
2452
2453 static int ip6_pkt_prohibit(struct sk_buff *skb)
2454 {
2455 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2456 }
2457
2458 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2459 {
2460 skb->dev = skb_dst(skb)->dev;
2461 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2462 }
2463
2464 /*
2465 * Allocate a dst for local (unicast / anycast) address.
2466 */
2467
2468 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2469 const struct in6_addr *addr,
2470 bool anycast)
2471 {
2472 struct net *net = dev_net(idev->dev);
2473 struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2474 DST_NOCOUNT);
2475 if (!rt)
2476 return ERR_PTR(-ENOMEM);
2477
2478 in6_dev_hold(idev);
2479
2480 rt->dst.flags |= DST_HOST;
2481 rt->dst.input = ip6_input;
2482 rt->dst.output = ip6_output;
2483 rt->rt6i_idev = idev;
2484
2485 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2486 if (anycast)
2487 rt->rt6i_flags |= RTF_ANYCAST;
2488 else
2489 rt->rt6i_flags |= RTF_LOCAL;
2490
2491 rt->rt6i_gateway = *addr;
2492 rt->rt6i_dst.addr = *addr;
2493 rt->rt6i_dst.plen = 128;
2494 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2495
2496 atomic_set(&rt->dst.__refcnt, 1);
2497
2498 return rt;
2499 }
2500
2501 int ip6_route_get_saddr(struct net *net,
2502 struct rt6_info *rt,
2503 const struct in6_addr *daddr,
2504 unsigned int prefs,
2505 struct in6_addr *saddr)
2506 {
2507 struct inet6_dev *idev =
2508 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2509 int err = 0;
2510 if (rt && rt->rt6i_prefsrc.plen)
2511 *saddr = rt->rt6i_prefsrc.addr;
2512 else
2513 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2514 daddr, prefs, saddr);
2515 return err;
2516 }
2517
2518 /* remove deleted ip from prefsrc entries */
2519 struct arg_dev_net_ip {
2520 struct net_device *dev;
2521 struct net *net;
2522 struct in6_addr *addr;
2523 };
2524
2525 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2526 {
2527 struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2528 struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2529 struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2530
2531 if (((void *)rt->dst.dev == dev || !dev) &&
2532 rt != net->ipv6.ip6_null_entry &&
2533 ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2534 /* remove prefsrc entry */
2535 rt->rt6i_prefsrc.plen = 0;
2536 }
2537 return 0;
2538 }
2539
2540 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2541 {
2542 struct net *net = dev_net(ifp->idev->dev);
2543 struct arg_dev_net_ip adni = {
2544 .dev = ifp->idev->dev,
2545 .net = net,
2546 .addr = &ifp->addr,
2547 };
2548 fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2549 }
2550
2551 #define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2552 #define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
2553
2554 /* Remove routers and update dst entries when gateway turn into host. */
2555 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2556 {
2557 struct in6_addr *gateway = (struct in6_addr *)arg;
2558
2559 if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2560 ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2561 ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2562 return -1;
2563 }
2564 return 0;
2565 }
2566
2567 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2568 {
2569 fib6_clean_all(net, fib6_clean_tohost, gateway);
2570 }
2571
2572 struct arg_dev_net {
2573 struct net_device *dev;
2574 struct net *net;
2575 };
2576
2577 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2578 {
2579 const struct arg_dev_net *adn = arg;
2580 const struct net_device *dev = adn->dev;
2581
2582 if ((rt->dst.dev == dev || !dev) &&
2583 rt != adn->net->ipv6.ip6_null_entry)
2584 return -1;
2585
2586 return 0;
2587 }
2588
2589 void rt6_ifdown(struct net *net, struct net_device *dev)
2590 {
2591 struct arg_dev_net adn = {
2592 .dev = dev,
2593 .net = net,
2594 };
2595
2596 fib6_clean_all(net, fib6_ifdown, &adn);
2597 icmp6_clean_all(fib6_ifdown, &adn);
2598 rt6_uncached_list_flush_dev(net, dev);
2599 }
2600
2601 struct rt6_mtu_change_arg {
2602 struct net_device *dev;
2603 unsigned int mtu;
2604 };
2605
2606 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2607 {
2608 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2609 struct inet6_dev *idev;
2610
2611 /* In IPv6 pmtu discovery is not optional,
2612 so that RTAX_MTU lock cannot disable it.
2613 We still use this lock to block changes
2614 caused by addrconf/ndisc.
2615 */
2616
2617 idev = __in6_dev_get(arg->dev);
2618 if (!idev)
2619 return 0;
2620
2621 /* For administrative MTU increase, there is no way to discover
2622 IPv6 PMTU increase, so PMTU increase should be updated here.
2623 Since RFC 1981 doesn't include administrative MTU increase
2624 update PMTU increase is a MUST. (i.e. jumbo frame)
2625 */
2626 /*
2627 If new MTU is less than route PMTU, this new MTU will be the
2628 lowest MTU in the path, update the route PMTU to reflect PMTU
2629 decreases; if new MTU is greater than route PMTU, and the
2630 old MTU is the lowest MTU in the path, update the route PMTU
2631 to reflect the increase. In this case if the other nodes' MTU
2632 also have the lowest MTU, TOO BIG MESSAGE will be lead to
2633 PMTU discouvery.
2634 */
2635 if (rt->dst.dev == arg->dev &&
2636 !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2637 if (rt->rt6i_flags & RTF_CACHE) {
2638 /* For RTF_CACHE with rt6i_pmtu == 0
2639 * (i.e. a redirected route),
2640 * the metrics of its rt->dst.from has already
2641 * been updated.
2642 */
2643 if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2644 rt->rt6i_pmtu = arg->mtu;
2645 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2646 (dst_mtu(&rt->dst) < arg->mtu &&
2647 dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2648 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2649 }
2650 }
2651 return 0;
2652 }
2653
2654 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2655 {
2656 struct rt6_mtu_change_arg arg = {
2657 .dev = dev,
2658 .mtu = mtu,
2659 };
2660
2661 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2662 }
2663
2664 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2665 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2666 [RTA_OIF] = { .type = NLA_U32 },
2667 [RTA_IIF] = { .type = NLA_U32 },
2668 [RTA_PRIORITY] = { .type = NLA_U32 },
2669 [RTA_METRICS] = { .type = NLA_NESTED },
2670 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2671 [RTA_PREF] = { .type = NLA_U8 },
2672 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
2673 [RTA_ENCAP] = { .type = NLA_NESTED },
2674 };
2675
2676 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2677 struct fib6_config *cfg)
2678 {
2679 struct rtmsg *rtm;
2680 struct nlattr *tb[RTA_MAX+1];
2681 unsigned int pref;
2682 int err;
2683
2684 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2685 if (err < 0)
2686 goto errout;
2687
2688 err = -EINVAL;
2689 rtm = nlmsg_data(nlh);
2690 memset(cfg, 0, sizeof(*cfg));
2691
2692 cfg->fc_table = rtm->rtm_table;
2693 cfg->fc_dst_len = rtm->rtm_dst_len;
2694 cfg->fc_src_len = rtm->rtm_src_len;
2695 cfg->fc_flags = RTF_UP;
2696 cfg->fc_protocol = rtm->rtm_protocol;
2697 cfg->fc_type = rtm->rtm_type;
2698
2699 if (rtm->rtm_type == RTN_UNREACHABLE ||
2700 rtm->rtm_type == RTN_BLACKHOLE ||
2701 rtm->rtm_type == RTN_PROHIBIT ||
2702 rtm->rtm_type == RTN_THROW)
2703 cfg->fc_flags |= RTF_REJECT;
2704
2705 if (rtm->rtm_type == RTN_LOCAL)
2706 cfg->fc_flags |= RTF_LOCAL;
2707
2708 if (rtm->rtm_flags & RTM_F_CLONED)
2709 cfg->fc_flags |= RTF_CACHE;
2710
2711 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2712 cfg->fc_nlinfo.nlh = nlh;
2713 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2714
2715 if (tb[RTA_GATEWAY]) {
2716 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2717 cfg->fc_flags |= RTF_GATEWAY;
2718 }
2719
2720 if (tb[RTA_DST]) {
2721 int plen = (rtm->rtm_dst_len + 7) >> 3;
2722
2723 if (nla_len(tb[RTA_DST]) < plen)
2724 goto errout;
2725
2726 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2727 }
2728
2729 if (tb[RTA_SRC]) {
2730 int plen = (rtm->rtm_src_len + 7) >> 3;
2731
2732 if (nla_len(tb[RTA_SRC]) < plen)
2733 goto errout;
2734
2735 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2736 }
2737
2738 if (tb[RTA_PREFSRC])
2739 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2740
2741 if (tb[RTA_OIF])
2742 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2743
2744 if (tb[RTA_PRIORITY])
2745 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2746
2747 if (tb[RTA_METRICS]) {
2748 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2749 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2750 }
2751
2752 if (tb[RTA_TABLE])
2753 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2754
2755 if (tb[RTA_MULTIPATH]) {
2756 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2757 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2758 }
2759
2760 if (tb[RTA_PREF]) {
2761 pref = nla_get_u8(tb[RTA_PREF]);
2762 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2763 pref != ICMPV6_ROUTER_PREF_HIGH)
2764 pref = ICMPV6_ROUTER_PREF_MEDIUM;
2765 cfg->fc_flags |= RTF_PREF(pref);
2766 }
2767
2768 if (tb[RTA_ENCAP])
2769 cfg->fc_encap = tb[RTA_ENCAP];
2770
2771 if (tb[RTA_ENCAP_TYPE])
2772 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2773
2774 err = 0;
2775 errout:
2776 return err;
2777 }
2778
2779 static int ip6_route_multipath(struct fib6_config *cfg, int add)
2780 {
2781 struct fib6_config r_cfg;
2782 struct rtnexthop *rtnh;
2783 int remaining;
2784 int attrlen;
2785 int err = 0, last_err = 0;
2786
2787 remaining = cfg->fc_mp_len;
2788 beginning:
2789 rtnh = (struct rtnexthop *)cfg->fc_mp;
2790
2791 /* Parse a Multipath Entry */
2792 while (rtnh_ok(rtnh, remaining)) {
2793 memcpy(&r_cfg, cfg, sizeof(*cfg));
2794 if (rtnh->rtnh_ifindex)
2795 r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2796
2797 attrlen = rtnh_attrlen(rtnh);
2798 if (attrlen > 0) {
2799 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2800
2801 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2802 if (nla) {
2803 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2804 r_cfg.fc_flags |= RTF_GATEWAY;
2805 }
2806 r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2807 nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2808 if (nla)
2809 r_cfg.fc_encap_type = nla_get_u16(nla);
2810 }
2811 err = add ? ip6_route_add(&r_cfg) : ip6_route_del(&r_cfg);
2812 if (err) {
2813 last_err = err;
2814 /* If we are trying to remove a route, do not stop the
2815 * loop when ip6_route_del() fails (because next hop is
2816 * already gone), we should try to remove all next hops.
2817 */
2818 if (add) {
2819 /* If add fails, we should try to delete all
2820 * next hops that have been already added.
2821 */
2822 add = 0;
2823 remaining = cfg->fc_mp_len - remaining;
2824 goto beginning;
2825 }
2826 }
2827 /* Because each route is added like a single route we remove
2828 * these flags after the first nexthop: if there is a collision,
2829 * we have already failed to add the first nexthop:
2830 * fib6_add_rt2node() has rejected it; when replacing, old
2831 * nexthops have been replaced by first new, the rest should
2832 * be added to it.
2833 */
2834 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2835 NLM_F_REPLACE);
2836 rtnh = rtnh_next(rtnh, &remaining);
2837 }
2838
2839 return last_err;
2840 }
2841
2842 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2843 {
2844 struct fib6_config cfg;
2845 int err;
2846
2847 err = rtm_to_fib6_config(skb, nlh, &cfg);
2848 if (err < 0)
2849 return err;
2850
2851 if (cfg.fc_mp)
2852 return ip6_route_multipath(&cfg, 0);
2853 else
2854 return ip6_route_del(&cfg);
2855 }
2856
2857 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2858 {
2859 struct fib6_config cfg;
2860 int err;
2861
2862 err = rtm_to_fib6_config(skb, nlh, &cfg);
2863 if (err < 0)
2864 return err;
2865
2866 if (cfg.fc_mp)
2867 return ip6_route_multipath(&cfg, 1);
2868 else
2869 return ip6_route_add(&cfg);
2870 }
2871
2872 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
2873 {
2874 return NLMSG_ALIGN(sizeof(struct rtmsg))
2875 + nla_total_size(16) /* RTA_SRC */
2876 + nla_total_size(16) /* RTA_DST */
2877 + nla_total_size(16) /* RTA_GATEWAY */
2878 + nla_total_size(16) /* RTA_PREFSRC */
2879 + nla_total_size(4) /* RTA_TABLE */
2880 + nla_total_size(4) /* RTA_IIF */
2881 + nla_total_size(4) /* RTA_OIF */
2882 + nla_total_size(4) /* RTA_PRIORITY */
2883 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2884 + nla_total_size(sizeof(struct rta_cacheinfo))
2885 + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
2886 + nla_total_size(1) /* RTA_PREF */
2887 + lwtunnel_get_encap_size(rt->dst.lwtstate);
2888 }
2889
2890 static int rt6_fill_node(struct net *net,
2891 struct sk_buff *skb, struct rt6_info *rt,
2892 struct in6_addr *dst, struct in6_addr *src,
2893 int iif, int type, u32 portid, u32 seq,
2894 int prefix, int nowait, unsigned int flags)
2895 {
2896 u32 metrics[RTAX_MAX];
2897 struct rtmsg *rtm;
2898 struct nlmsghdr *nlh;
2899 long expires;
2900 u32 table;
2901
2902 if (prefix) { /* user wants prefix routes only */
2903 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2904 /* success since this is not a prefix route */
2905 return 1;
2906 }
2907 }
2908
2909 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
2910 if (!nlh)
2911 return -EMSGSIZE;
2912
2913 rtm = nlmsg_data(nlh);
2914 rtm->rtm_family = AF_INET6;
2915 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2916 rtm->rtm_src_len = rt->rt6i_src.plen;
2917 rtm->rtm_tos = 0;
2918 if (rt->rt6i_table)
2919 table = rt->rt6i_table->tb6_id;
2920 else
2921 table = RT6_TABLE_UNSPEC;
2922 rtm->rtm_table = table;
2923 if (nla_put_u32(skb, RTA_TABLE, table))
2924 goto nla_put_failure;
2925 if (rt->rt6i_flags & RTF_REJECT) {
2926 switch (rt->dst.error) {
2927 case -EINVAL:
2928 rtm->rtm_type = RTN_BLACKHOLE;
2929 break;
2930 case -EACCES:
2931 rtm->rtm_type = RTN_PROHIBIT;
2932 break;
2933 case -EAGAIN:
2934 rtm->rtm_type = RTN_THROW;
2935 break;
2936 default:
2937 rtm->rtm_type = RTN_UNREACHABLE;
2938 break;
2939 }
2940 }
2941 else if (rt->rt6i_flags & RTF_LOCAL)
2942 rtm->rtm_type = RTN_LOCAL;
2943 else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
2944 rtm->rtm_type = RTN_LOCAL;
2945 else
2946 rtm->rtm_type = RTN_UNICAST;
2947 rtm->rtm_flags = 0;
2948 if (!netif_carrier_ok(rt->dst.dev)) {
2949 rtm->rtm_flags |= RTNH_F_LINKDOWN;
2950 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
2951 rtm->rtm_flags |= RTNH_F_DEAD;
2952 }
2953 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2954 rtm->rtm_protocol = rt->rt6i_protocol;
2955 if (rt->rt6i_flags & RTF_DYNAMIC)
2956 rtm->rtm_protocol = RTPROT_REDIRECT;
2957 else if (rt->rt6i_flags & RTF_ADDRCONF) {
2958 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
2959 rtm->rtm_protocol = RTPROT_RA;
2960 else
2961 rtm->rtm_protocol = RTPROT_KERNEL;
2962 }
2963
2964 if (rt->rt6i_flags & RTF_CACHE)
2965 rtm->rtm_flags |= RTM_F_CLONED;
2966
2967 if (dst) {
2968 if (nla_put_in6_addr(skb, RTA_DST, dst))
2969 goto nla_put_failure;
2970 rtm->rtm_dst_len = 128;
2971 } else if (rtm->rtm_dst_len)
2972 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
2973 goto nla_put_failure;
2974 #ifdef CONFIG_IPV6_SUBTREES
2975 if (src) {
2976 if (nla_put_in6_addr(skb, RTA_SRC, src))
2977 goto nla_put_failure;
2978 rtm->rtm_src_len = 128;
2979 } else if (rtm->rtm_src_len &&
2980 nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
2981 goto nla_put_failure;
2982 #endif
2983 if (iif) {
2984 #ifdef CONFIG_IPV6_MROUTE
2985 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2986 int err = ip6mr_get_route(net, skb, rtm, nowait);
2987 if (err <= 0) {
2988 if (!nowait) {
2989 if (err == 0)
2990 return 0;
2991 goto nla_put_failure;
2992 } else {
2993 if (err == -EMSGSIZE)
2994 goto nla_put_failure;
2995 }
2996 }
2997 } else
2998 #endif
2999 if (nla_put_u32(skb, RTA_IIF, iif))
3000 goto nla_put_failure;
3001 } else if (dst) {
3002 struct in6_addr saddr_buf;
3003 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3004 nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3005 goto nla_put_failure;
3006 }
3007
3008 if (rt->rt6i_prefsrc.plen) {
3009 struct in6_addr saddr_buf;
3010 saddr_buf = rt->rt6i_prefsrc.addr;
3011 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3012 goto nla_put_failure;
3013 }
3014
3015 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3016 if (rt->rt6i_pmtu)
3017 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3018 if (rtnetlink_put_metrics(skb, metrics) < 0)
3019 goto nla_put_failure;
3020
3021 if (rt->rt6i_flags & RTF_GATEWAY) {
3022 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3023 goto nla_put_failure;
3024 }
3025
3026 if (rt->dst.dev &&
3027 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3028 goto nla_put_failure;
3029 if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3030 goto nla_put_failure;
3031
3032 expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3033
3034 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3035 goto nla_put_failure;
3036
3037 if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3038 goto nla_put_failure;
3039
3040 lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3041
3042 nlmsg_end(skb, nlh);
3043 return 0;
3044
3045 nla_put_failure:
3046 nlmsg_cancel(skb, nlh);
3047 return -EMSGSIZE;
3048 }
3049
3050 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3051 {
3052 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3053 int prefix;
3054
3055 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3056 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3057 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3058 } else
3059 prefix = 0;
3060
3061 return rt6_fill_node(arg->net,
3062 arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3063 NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3064 prefix, 0, NLM_F_MULTI);
3065 }
3066
3067 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3068 {
3069 struct net *net = sock_net(in_skb->sk);
3070 struct nlattr *tb[RTA_MAX+1];
3071 struct rt6_info *rt;
3072 struct sk_buff *skb;
3073 struct rtmsg *rtm;
3074 struct flowi6 fl6;
3075 int err, iif = 0, oif = 0;
3076
3077 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3078 if (err < 0)
3079 goto errout;
3080
3081 err = -EINVAL;
3082 memset(&fl6, 0, sizeof(fl6));
3083
3084 if (tb[RTA_SRC]) {
3085 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3086 goto errout;
3087
3088 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3089 }
3090
3091 if (tb[RTA_DST]) {
3092 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3093 goto errout;
3094
3095 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3096 }
3097
3098 if (tb[RTA_IIF])
3099 iif = nla_get_u32(tb[RTA_IIF]);
3100
3101 if (tb[RTA_OIF])
3102 oif = nla_get_u32(tb[RTA_OIF]);
3103
3104 if (tb[RTA_MARK])
3105 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3106
3107 if (iif) {
3108 struct net_device *dev;
3109 int flags = 0;
3110
3111 dev = __dev_get_by_index(net, iif);
3112 if (!dev) {
3113 err = -ENODEV;
3114 goto errout;
3115 }
3116
3117 fl6.flowi6_iif = iif;
3118
3119 if (!ipv6_addr_any(&fl6.saddr))
3120 flags |= RT6_LOOKUP_F_HAS_SADDR;
3121
3122 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3123 flags);
3124 } else {
3125 fl6.flowi6_oif = oif;
3126
3127 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3128 }
3129
3130 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3131 if (!skb) {
3132 ip6_rt_put(rt);
3133 err = -ENOBUFS;
3134 goto errout;
3135 }
3136
3137 /* Reserve room for dummy headers, this skb can pass
3138 through good chunk of routing engine.
3139 */
3140 skb_reset_mac_header(skb);
3141 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3142
3143 skb_dst_set(skb, &rt->dst);
3144
3145 err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3146 RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3147 nlh->nlmsg_seq, 0, 0, 0);
3148 if (err < 0) {
3149 kfree_skb(skb);
3150 goto errout;
3151 }
3152
3153 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3154 errout:
3155 return err;
3156 }
3157
3158 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
3159 {
3160 struct sk_buff *skb;
3161 struct net *net = info->nl_net;
3162 u32 seq;
3163 int err;
3164
3165 err = -ENOBUFS;
3166 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3167
3168 skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3169 if (!skb)
3170 goto errout;
3171
3172 err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3173 event, info->portid, seq, 0, 0, 0);
3174 if (err < 0) {
3175 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3176 WARN_ON(err == -EMSGSIZE);
3177 kfree_skb(skb);
3178 goto errout;
3179 }
3180 rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3181 info->nlh, gfp_any());
3182 return;
3183 errout:
3184 if (err < 0)
3185 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3186 }
3187
3188 static int ip6_route_dev_notify(struct notifier_block *this,
3189 unsigned long event, void *ptr)
3190 {
3191 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3192 struct net *net = dev_net(dev);
3193
3194 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3195 net->ipv6.ip6_null_entry->dst.dev = dev;
3196 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3197 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3198 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3199 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3200 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3201 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3202 #endif
3203 }
3204
3205 return NOTIFY_OK;
3206 }
3207
3208 /*
3209 * /proc
3210 */
3211
3212 #ifdef CONFIG_PROC_FS
3213
3214 static const struct file_operations ipv6_route_proc_fops = {
3215 .owner = THIS_MODULE,
3216 .open = ipv6_route_open,
3217 .read = seq_read,
3218 .llseek = seq_lseek,
3219 .release = seq_release_net,
3220 };
3221
3222 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3223 {
3224 struct net *net = (struct net *)seq->private;
3225 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3226 net->ipv6.rt6_stats->fib_nodes,
3227 net->ipv6.rt6_stats->fib_route_nodes,
3228 net->ipv6.rt6_stats->fib_rt_alloc,
3229 net->ipv6.rt6_stats->fib_rt_entries,
3230 net->ipv6.rt6_stats->fib_rt_cache,
3231 dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3232 net->ipv6.rt6_stats->fib_discarded_routes);
3233
3234 return 0;
3235 }
3236
3237 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3238 {
3239 return single_open_net(inode, file, rt6_stats_seq_show);
3240 }
3241
3242 static const struct file_operations rt6_stats_seq_fops = {
3243 .owner = THIS_MODULE,
3244 .open = rt6_stats_seq_open,
3245 .read = seq_read,
3246 .llseek = seq_lseek,
3247 .release = single_release_net,
3248 };
3249 #endif /* CONFIG_PROC_FS */
3250
3251 #ifdef CONFIG_SYSCTL
3252
3253 static
3254 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3255 void __user *buffer, size_t *lenp, loff_t *ppos)
3256 {
3257 struct net *net;
3258 int delay;
3259 if (!write)
3260 return -EINVAL;
3261
3262 net = (struct net *)ctl->extra1;
3263 delay = net->ipv6.sysctl.flush_delay;
3264 proc_dointvec(ctl, write, buffer, lenp, ppos);
3265 fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3266 return 0;
3267 }
3268
3269 struct ctl_table ipv6_route_table_template[] = {
3270 {
3271 .procname = "flush",
3272 .data = &init_net.ipv6.sysctl.flush_delay,
3273 .maxlen = sizeof(int),
3274 .mode = 0200,
3275 .proc_handler = ipv6_sysctl_rtcache_flush
3276 },
3277 {
3278 .procname = "gc_thresh",
3279 .data = &ip6_dst_ops_template.gc_thresh,
3280 .maxlen = sizeof(int),
3281 .mode = 0644,
3282 .proc_handler = proc_dointvec,
3283 },
3284 {
3285 .procname = "max_size",
3286 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
3287 .maxlen = sizeof(int),
3288 .mode = 0644,
3289 .proc_handler = proc_dointvec,
3290 },
3291 {
3292 .procname = "gc_min_interval",
3293 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3294 .maxlen = sizeof(int),
3295 .mode = 0644,
3296 .proc_handler = proc_dointvec_jiffies,
3297 },
3298 {
3299 .procname = "gc_timeout",
3300 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3301 .maxlen = sizeof(int),
3302 .mode = 0644,
3303 .proc_handler = proc_dointvec_jiffies,
3304 },
3305 {
3306 .procname = "gc_interval",
3307 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3308 .maxlen = sizeof(int),
3309 .mode = 0644,
3310 .proc_handler = proc_dointvec_jiffies,
3311 },
3312 {
3313 .procname = "gc_elasticity",
3314 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3315 .maxlen = sizeof(int),
3316 .mode = 0644,
3317 .proc_handler = proc_dointvec,
3318 },
3319 {
3320 .procname = "mtu_expires",
3321 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3322 .maxlen = sizeof(int),
3323 .mode = 0644,
3324 .proc_handler = proc_dointvec_jiffies,
3325 },
3326 {
3327 .procname = "min_adv_mss",
3328 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3329 .maxlen = sizeof(int),
3330 .mode = 0644,
3331 .proc_handler = proc_dointvec,
3332 },
3333 {
3334 .procname = "gc_min_interval_ms",
3335 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3336 .maxlen = sizeof(int),
3337 .mode = 0644,
3338 .proc_handler = proc_dointvec_ms_jiffies,
3339 },
3340 { }
3341 };
3342
3343 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3344 {
3345 struct ctl_table *table;
3346
3347 table = kmemdup(ipv6_route_table_template,
3348 sizeof(ipv6_route_table_template),
3349 GFP_KERNEL);
3350
3351 if (table) {
3352 table[0].data = &net->ipv6.sysctl.flush_delay;
3353 table[0].extra1 = net;
3354 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3355 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3356 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3357 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3358 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3359 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3360 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3361 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3362 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3363
3364 /* Don't export sysctls to unprivileged users */
3365 if (net->user_ns != &init_user_ns)
3366 table[0].procname = NULL;
3367 }
3368
3369 return table;
3370 }
3371 #endif
3372
3373 static int __net_init ip6_route_net_init(struct net *net)
3374 {
3375 int ret = -ENOMEM;
3376
3377 memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3378 sizeof(net->ipv6.ip6_dst_ops));
3379
3380 if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3381 goto out_ip6_dst_ops;
3382
3383 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3384 sizeof(*net->ipv6.ip6_null_entry),
3385 GFP_KERNEL);
3386 if (!net->ipv6.ip6_null_entry)
3387 goto out_ip6_dst_entries;
3388 net->ipv6.ip6_null_entry->dst.path =
3389 (struct dst_entry *)net->ipv6.ip6_null_entry;
3390 net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3391 dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3392 ip6_template_metrics, true);
3393
3394 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3395 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3396 sizeof(*net->ipv6.ip6_prohibit_entry),
3397 GFP_KERNEL);
3398 if (!net->ipv6.ip6_prohibit_entry)
3399 goto out_ip6_null_entry;
3400 net->ipv6.ip6_prohibit_entry->dst.path =
3401 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3402 net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3403 dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3404 ip6_template_metrics, true);
3405
3406 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3407 sizeof(*net->ipv6.ip6_blk_hole_entry),
3408 GFP_KERNEL);
3409 if (!net->ipv6.ip6_blk_hole_entry)
3410 goto out_ip6_prohibit_entry;
3411 net->ipv6.ip6_blk_hole_entry->dst.path =
3412 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3413 net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3414 dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3415 ip6_template_metrics, true);
3416 #endif
3417
3418 net->ipv6.sysctl.flush_delay = 0;
3419 net->ipv6.sysctl.ip6_rt_max_size = 4096;
3420 net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3421 net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3422 net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3423 net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3424 net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3425 net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3426
3427 net->ipv6.ip6_rt_gc_expire = 30*HZ;
3428
3429 ret = 0;
3430 out:
3431 return ret;
3432
3433 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3434 out_ip6_prohibit_entry:
3435 kfree(net->ipv6.ip6_prohibit_entry);
3436 out_ip6_null_entry:
3437 kfree(net->ipv6.ip6_null_entry);
3438 #endif
3439 out_ip6_dst_entries:
3440 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3441 out_ip6_dst_ops:
3442 goto out;
3443 }
3444
3445 static void __net_exit ip6_route_net_exit(struct net *net)
3446 {
3447 kfree(net->ipv6.ip6_null_entry);
3448 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3449 kfree(net->ipv6.ip6_prohibit_entry);
3450 kfree(net->ipv6.ip6_blk_hole_entry);
3451 #endif
3452 dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3453 }
3454
3455 static int __net_init ip6_route_net_init_late(struct net *net)
3456 {
3457 #ifdef CONFIG_PROC_FS
3458 proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3459 proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3460 #endif
3461 return 0;
3462 }
3463
3464 static void __net_exit ip6_route_net_exit_late(struct net *net)
3465 {
3466 #ifdef CONFIG_PROC_FS
3467 remove_proc_entry("ipv6_route", net->proc_net);
3468 remove_proc_entry("rt6_stats", net->proc_net);
3469 #endif
3470 }
3471
3472 static struct pernet_operations ip6_route_net_ops = {
3473 .init = ip6_route_net_init,
3474 .exit = ip6_route_net_exit,
3475 };
3476
3477 static int __net_init ipv6_inetpeer_init(struct net *net)
3478 {
3479 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3480
3481 if (!bp)
3482 return -ENOMEM;
3483 inet_peer_base_init(bp);
3484 net->ipv6.peers = bp;
3485 return 0;
3486 }
3487
3488 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3489 {
3490 struct inet_peer_base *bp = net->ipv6.peers;
3491
3492 net->ipv6.peers = NULL;
3493 inetpeer_invalidate_tree(bp);
3494 kfree(bp);
3495 }
3496
3497 static struct pernet_operations ipv6_inetpeer_ops = {
3498 .init = ipv6_inetpeer_init,
3499 .exit = ipv6_inetpeer_exit,
3500 };
3501
3502 static struct pernet_operations ip6_route_net_late_ops = {
3503 .init = ip6_route_net_init_late,
3504 .exit = ip6_route_net_exit_late,
3505 };
3506
3507 static struct notifier_block ip6_route_dev_notifier = {
3508 .notifier_call = ip6_route_dev_notify,
3509 .priority = 0,
3510 };
3511
3512 int __init ip6_route_init(void)
3513 {
3514 int ret;
3515 int cpu;
3516
3517 ret = -ENOMEM;
3518 ip6_dst_ops_template.kmem_cachep =
3519 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3520 SLAB_HWCACHE_ALIGN, NULL);
3521 if (!ip6_dst_ops_template.kmem_cachep)
3522 goto out;
3523
3524 ret = dst_entries_init(&ip6_dst_blackhole_ops);
3525 if (ret)
3526 goto out_kmem_cache;
3527
3528 ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3529 if (ret)
3530 goto out_dst_entries;
3531
3532 ret = register_pernet_subsys(&ip6_route_net_ops);
3533 if (ret)
3534 goto out_register_inetpeer;
3535
3536 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3537
3538 /* Registering of the loopback is done before this portion of code,
3539 * the loopback reference in rt6_info will not be taken, do it
3540 * manually for init_net */
3541 init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3542 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3543 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3544 init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3545 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3546 init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3547 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3548 #endif
3549 ret = fib6_init();
3550 if (ret)
3551 goto out_register_subsys;
3552
3553 ret = xfrm6_init();
3554 if (ret)
3555 goto out_fib6_init;
3556
3557 ret = fib6_rules_init();
3558 if (ret)
3559 goto xfrm6_init;
3560
3561 ret = register_pernet_subsys(&ip6_route_net_late_ops);
3562 if (ret)
3563 goto fib6_rules_init;
3564
3565 ret = -ENOBUFS;
3566 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3567 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3568 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3569 goto out_register_late_subsys;
3570
3571 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3572 if (ret)
3573 goto out_register_late_subsys;
3574
3575 for_each_possible_cpu(cpu) {
3576 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3577
3578 INIT_LIST_HEAD(&ul->head);
3579 spin_lock_init(&ul->lock);
3580 }
3581
3582 out:
3583 return ret;
3584
3585 out_register_late_subsys:
3586 unregister_pernet_subsys(&ip6_route_net_late_ops);
3587 fib6_rules_init:
3588 fib6_rules_cleanup();
3589 xfrm6_init:
3590 xfrm6_fini();
3591 out_fib6_init:
3592 fib6_gc_cleanup();
3593 out_register_subsys:
3594 unregister_pernet_subsys(&ip6_route_net_ops);
3595 out_register_inetpeer:
3596 unregister_pernet_subsys(&ipv6_inetpeer_ops);
3597 out_dst_entries:
3598 dst_entries_destroy(&ip6_dst_blackhole_ops);
3599 out_kmem_cache:
3600 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3601 goto out;
3602 }
3603
3604 void ip6_route_cleanup(void)
3605 {
3606 unregister_netdevice_notifier(&ip6_route_dev_notifier);
3607 unregister_pernet_subsys(&ip6_route_net_late_ops);
3608 fib6_rules_cleanup();
3609 xfrm6_fini();
3610 fib6_gc_cleanup();
3611 unregister_pernet_subsys(&ipv6_inetpeer_ops);
3612 unregister_pernet_subsys(&ip6_route_net_ops);
3613 dst_entries_destroy(&ip6_dst_blackhole_ops);
3614 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3615 }
Linux kernel - Deliverables
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