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[~andy/linux] / 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/xfrm.h>
58 #include <net/netevent.h>
59 #include <net/netlink.h>
60 #include <net/nexthop.h>
61
62 #include <asm/uaccess.h>
63
64 #ifdef CONFIG_SYSCTL
65 #include <linux/sysctl.h>
66 #endif
67
68 enum rt6_nud_state {
69         RT6_NUD_FAIL_HARD = -3,
70         RT6_NUD_FAIL_PROBE = -2,
71         RT6_NUD_FAIL_DO_RR = -1,
72         RT6_NUD_SUCCEED = 1
73 };
74
75 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
76                                     const struct in6_addr *dest);
77 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
78 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
79 static unsigned int      ip6_mtu(const struct dst_entry *dst);
80 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
81 static void             ip6_dst_destroy(struct dst_entry *);
82 static void             ip6_dst_ifdown(struct dst_entry *,
83                                        struct net_device *dev, int how);
84 static int               ip6_dst_gc(struct dst_ops *ops);
85
86 static int              ip6_pkt_discard(struct sk_buff *skb);
87 static int              ip6_pkt_discard_out(struct sk_buff *skb);
88 static int              ip6_pkt_prohibit(struct sk_buff *skb);
89 static int              ip6_pkt_prohibit_out(struct sk_buff *skb);
90 static void             ip6_link_failure(struct sk_buff *skb);
91 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
92                                            struct sk_buff *skb, u32 mtu);
93 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
94                                         struct sk_buff *skb);
95 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
96
97 #ifdef CONFIG_IPV6_ROUTE_INFO
98 static struct rt6_info *rt6_add_route_info(struct net *net,
99                                            const struct in6_addr *prefix, int prefixlen,
100                                            const struct in6_addr *gwaddr, int ifindex,
101                                            unsigned int pref);
102 static struct rt6_info *rt6_get_route_info(struct net *net,
103                                            const struct in6_addr *prefix, int prefixlen,
104                                            const struct in6_addr *gwaddr, int ifindex);
105 #endif
106
107 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
108 {
109         struct rt6_info *rt = (struct rt6_info *) dst;
110         struct inet_peer *peer;
111         u32 *p = NULL;
112
113         if (!(rt->dst.flags & DST_HOST))
114                 return NULL;
115
116         peer = rt6_get_peer_create(rt);
117         if (peer) {
118                 u32 *old_p = __DST_METRICS_PTR(old);
119                 unsigned long prev, new;
120
121                 p = peer->metrics;
122                 if (inet_metrics_new(peer))
123                         memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
124
125                 new = (unsigned long) p;
126                 prev = cmpxchg(&dst->_metrics, old, new);
127
128                 if (prev != old) {
129                         p = __DST_METRICS_PTR(prev);
130                         if (prev & DST_METRICS_READ_ONLY)
131                                 p = NULL;
132                 }
133         }
134         return p;
135 }
136
137 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
138                                              struct sk_buff *skb,
139                                              const void *daddr)
140 {
141         struct in6_addr *p = &rt->rt6i_gateway;
142
143         if (!ipv6_addr_any(p))
144                 return (const void *) p;
145         else if (skb)
146                 return &ipv6_hdr(skb)->daddr;
147         return daddr;
148 }
149
150 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
151                                           struct sk_buff *skb,
152                                           const void *daddr)
153 {
154         struct rt6_info *rt = (struct rt6_info *) dst;
155         struct neighbour *n;
156
157         daddr = choose_neigh_daddr(rt, skb, daddr);
158         n = __ipv6_neigh_lookup(dst->dev, daddr);
159         if (n)
160                 return n;
161         return neigh_create(&nd_tbl, daddr, dst->dev);
162 }
163
164 static struct dst_ops ip6_dst_ops_template = {
165         .family                 =       AF_INET6,
166         .protocol               =       cpu_to_be16(ETH_P_IPV6),
167         .gc                     =       ip6_dst_gc,
168         .gc_thresh              =       1024,
169         .check                  =       ip6_dst_check,
170         .default_advmss         =       ip6_default_advmss,
171         .mtu                    =       ip6_mtu,
172         .cow_metrics            =       ipv6_cow_metrics,
173         .destroy                =       ip6_dst_destroy,
174         .ifdown                 =       ip6_dst_ifdown,
175         .negative_advice        =       ip6_negative_advice,
176         .link_failure           =       ip6_link_failure,
177         .update_pmtu            =       ip6_rt_update_pmtu,
178         .redirect               =       rt6_do_redirect,
179         .local_out              =       __ip6_local_out,
180         .neigh_lookup           =       ip6_neigh_lookup,
181 };
182
183 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
184 {
185         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
186
187         return mtu ? : dst->dev->mtu;
188 }
189
190 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
191                                          struct sk_buff *skb, u32 mtu)
192 {
193 }
194
195 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
196                                       struct sk_buff *skb)
197 {
198 }
199
200 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
201                                          unsigned long old)
202 {
203         return NULL;
204 }
205
206 static struct dst_ops ip6_dst_blackhole_ops = {
207         .family                 =       AF_INET6,
208         .protocol               =       cpu_to_be16(ETH_P_IPV6),
209         .destroy                =       ip6_dst_destroy,
210         .check                  =       ip6_dst_check,
211         .mtu                    =       ip6_blackhole_mtu,
212         .default_advmss         =       ip6_default_advmss,
213         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
214         .redirect               =       ip6_rt_blackhole_redirect,
215         .cow_metrics            =       ip6_rt_blackhole_cow_metrics,
216         .neigh_lookup           =       ip6_neigh_lookup,
217 };
218
219 static const u32 ip6_template_metrics[RTAX_MAX] = {
220         [RTAX_HOPLIMIT - 1] = 0,
221 };
222
223 static const struct rt6_info ip6_null_entry_template = {
224         .dst = {
225                 .__refcnt       = ATOMIC_INIT(1),
226                 .__use          = 1,
227                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
228                 .error          = -ENETUNREACH,
229                 .input          = ip6_pkt_discard,
230                 .output         = ip6_pkt_discard_out,
231         },
232         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
233         .rt6i_protocol  = RTPROT_KERNEL,
234         .rt6i_metric    = ~(u32) 0,
235         .rt6i_ref       = ATOMIC_INIT(1),
236 };
237
238 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
239
240 static const struct rt6_info ip6_prohibit_entry_template = {
241         .dst = {
242                 .__refcnt       = ATOMIC_INIT(1),
243                 .__use          = 1,
244                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
245                 .error          = -EACCES,
246                 .input          = ip6_pkt_prohibit,
247                 .output         = ip6_pkt_prohibit_out,
248         },
249         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
250         .rt6i_protocol  = RTPROT_KERNEL,
251         .rt6i_metric    = ~(u32) 0,
252         .rt6i_ref       = ATOMIC_INIT(1),
253 };
254
255 static const struct rt6_info ip6_blk_hole_entry_template = {
256         .dst = {
257                 .__refcnt       = ATOMIC_INIT(1),
258                 .__use          = 1,
259                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
260                 .error          = -EINVAL,
261                 .input          = dst_discard,
262                 .output         = dst_discard,
263         },
264         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
265         .rt6i_protocol  = RTPROT_KERNEL,
266         .rt6i_metric    = ~(u32) 0,
267         .rt6i_ref       = ATOMIC_INIT(1),
268 };
269
270 #endif
271
272 /* allocate dst with ip6_dst_ops */
273 static inline struct rt6_info *ip6_dst_alloc(struct net *net,
274                                              struct net_device *dev,
275                                              int flags,
276                                              struct fib6_table *table)
277 {
278         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
279                                         0, DST_OBSOLETE_FORCE_CHK, flags);
280
281         if (rt) {
282                 struct dst_entry *dst = &rt->dst;
283
284                 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
285                 rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers);
286                 rt->rt6i_genid = rt_genid_ipv6(net);
287                 INIT_LIST_HEAD(&rt->rt6i_siblings);
288         }
289         return rt;
290 }
291
292 static void ip6_dst_destroy(struct dst_entry *dst)
293 {
294         struct rt6_info *rt = (struct rt6_info *)dst;
295         struct inet6_dev *idev = rt->rt6i_idev;
296         struct dst_entry *from = dst->from;
297
298         if (!(rt->dst.flags & DST_HOST))
299                 dst_destroy_metrics_generic(dst);
300
301         if (idev) {
302                 rt->rt6i_idev = NULL;
303                 in6_dev_put(idev);
304         }
305
306         dst->from = NULL;
307         dst_release(from);
308
309         if (rt6_has_peer(rt)) {
310                 struct inet_peer *peer = rt6_peer_ptr(rt);
311                 inet_putpeer(peer);
312         }
313 }
314
315 void rt6_bind_peer(struct rt6_info *rt, int create)
316 {
317         struct inet_peer_base *base;
318         struct inet_peer *peer;
319
320         base = inetpeer_base_ptr(rt->_rt6i_peer);
321         if (!base)
322                 return;
323
324         peer = inet_getpeer_v6(base, &rt->rt6i_dst.addr, create);
325         if (peer) {
326                 if (!rt6_set_peer(rt, peer))
327                         inet_putpeer(peer);
328         }
329 }
330
331 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
332                            int how)
333 {
334         struct rt6_info *rt = (struct rt6_info *)dst;
335         struct inet6_dev *idev = rt->rt6i_idev;
336         struct net_device *loopback_dev =
337                 dev_net(dev)->loopback_dev;
338
339         if (dev != loopback_dev) {
340                 if (idev && idev->dev == dev) {
341                         struct inet6_dev *loopback_idev =
342                                 in6_dev_get(loopback_dev);
343                         if (loopback_idev) {
344                                 rt->rt6i_idev = loopback_idev;
345                                 in6_dev_put(idev);
346                         }
347                 }
348         }
349 }
350
351 static bool rt6_check_expired(const struct rt6_info *rt)
352 {
353         if (rt->rt6i_flags & RTF_EXPIRES) {
354                 if (time_after(jiffies, rt->dst.expires))
355                         return true;
356         } else if (rt->dst.from) {
357                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
358         }
359         return false;
360 }
361
362 static bool rt6_need_strict(const struct in6_addr *daddr)
363 {
364         return ipv6_addr_type(daddr) &
365                 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
366 }
367
368 /* Multipath route selection:
369  *   Hash based function using packet header and flowlabel.
370  * Adapted from fib_info_hashfn()
371  */
372 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
373                                const struct flowi6 *fl6)
374 {
375         unsigned int val = fl6->flowi6_proto;
376
377         val ^= ipv6_addr_hash(&fl6->daddr);
378         val ^= ipv6_addr_hash(&fl6->saddr);
379
380         /* Work only if this not encapsulated */
381         switch (fl6->flowi6_proto) {
382         case IPPROTO_UDP:
383         case IPPROTO_TCP:
384         case IPPROTO_SCTP:
385                 val ^= (__force u16)fl6->fl6_sport;
386                 val ^= (__force u16)fl6->fl6_dport;
387                 break;
388
389         case IPPROTO_ICMPV6:
390                 val ^= (__force u16)fl6->fl6_icmp_type;
391                 val ^= (__force u16)fl6->fl6_icmp_code;
392                 break;
393         }
394         /* RFC6438 recommands to use flowlabel */
395         val ^= (__force u32)fl6->flowlabel;
396
397         /* Perhaps, we need to tune, this function? */
398         val = val ^ (val >> 7) ^ (val >> 12);
399         return val % candidate_count;
400 }
401
402 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
403                                              struct flowi6 *fl6, int oif,
404                                              int strict)
405 {
406         struct rt6_info *sibling, *next_sibling;
407         int route_choosen;
408
409         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
410         /* Don't change the route, if route_choosen == 0
411          * (siblings does not include ourself)
412          */
413         if (route_choosen)
414                 list_for_each_entry_safe(sibling, next_sibling,
415                                 &match->rt6i_siblings, rt6i_siblings) {
416                         route_choosen--;
417                         if (route_choosen == 0) {
418                                 if (rt6_score_route(sibling, oif, strict) < 0)
419                                         break;
420                                 match = sibling;
421                                 break;
422                         }
423                 }
424         return match;
425 }
426
427 /*
428  *      Route lookup. Any table->tb6_lock is implied.
429  */
430
431 static inline struct rt6_info *rt6_device_match(struct net *net,
432                                                     struct rt6_info *rt,
433                                                     const struct in6_addr *saddr,
434                                                     int oif,
435                                                     int flags)
436 {
437         struct rt6_info *local = NULL;
438         struct rt6_info *sprt;
439
440         if (!oif && ipv6_addr_any(saddr))
441                 goto out;
442
443         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
444                 struct net_device *dev = sprt->dst.dev;
445
446                 if (oif) {
447                         if (dev->ifindex == oif)
448                                 return sprt;
449                         if (dev->flags & IFF_LOOPBACK) {
450                                 if (!sprt->rt6i_idev ||
451                                     sprt->rt6i_idev->dev->ifindex != oif) {
452                                         if (flags & RT6_LOOKUP_F_IFACE && oif)
453                                                 continue;
454                                         if (local && (!oif ||
455                                                       local->rt6i_idev->dev->ifindex == oif))
456                                                 continue;
457                                 }
458                                 local = sprt;
459                         }
460                 } else {
461                         if (ipv6_chk_addr(net, saddr, dev,
462                                           flags & RT6_LOOKUP_F_IFACE))
463                                 return sprt;
464                 }
465         }
466
467         if (oif) {
468                 if (local)
469                         return local;
470
471                 if (flags & RT6_LOOKUP_F_IFACE)
472                         return net->ipv6.ip6_null_entry;
473         }
474 out:
475         return rt;
476 }
477
478 #ifdef CONFIG_IPV6_ROUTER_PREF
479 struct __rt6_probe_work {
480         struct work_struct work;
481         struct in6_addr target;
482         struct net_device *dev;
483 };
484
485 static void rt6_probe_deferred(struct work_struct *w)
486 {
487         struct in6_addr mcaddr;
488         struct __rt6_probe_work *work =
489                 container_of(w, struct __rt6_probe_work, work);
490
491         addrconf_addr_solict_mult(&work->target, &mcaddr);
492         ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL);
493         dev_put(work->dev);
494         kfree(w);
495 }
496
497 static void rt6_probe(struct rt6_info *rt)
498 {
499         struct neighbour *neigh;
500         /*
501          * Okay, this does not seem to be appropriate
502          * for now, however, we need to check if it
503          * is really so; aka Router Reachability Probing.
504          *
505          * Router Reachability Probe MUST be rate-limited
506          * to no more than one per minute.
507          */
508         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
509                 return;
510         rcu_read_lock_bh();
511         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
512         if (neigh) {
513                 write_lock(&neigh->lock);
514                 if (neigh->nud_state & NUD_VALID)
515                         goto out;
516         }
517
518         if (!neigh ||
519             time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
520                 struct __rt6_probe_work *work;
521
522                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
523
524                 if (neigh && work)
525                         __neigh_set_probe_once(neigh);
526
527                 if (neigh)
528                         write_unlock(&neigh->lock);
529
530                 if (work) {
531                         INIT_WORK(&work->work, rt6_probe_deferred);
532                         work->target = rt->rt6i_gateway;
533                         dev_hold(rt->dst.dev);
534                         work->dev = rt->dst.dev;
535                         schedule_work(&work->work);
536                 }
537         } else {
538 out:
539                 write_unlock(&neigh->lock);
540         }
541         rcu_read_unlock_bh();
542 }
543 #else
544 static inline void rt6_probe(struct rt6_info *rt)
545 {
546 }
547 #endif
548
549 /*
550  * Default Router Selection (RFC 2461 6.3.6)
551  */
552 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
553 {
554         struct net_device *dev = rt->dst.dev;
555         if (!oif || dev->ifindex == oif)
556                 return 2;
557         if ((dev->flags & IFF_LOOPBACK) &&
558             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
559                 return 1;
560         return 0;
561 }
562
563 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
564 {
565         struct neighbour *neigh;
566         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
567
568         if (rt->rt6i_flags & RTF_NONEXTHOP ||
569             !(rt->rt6i_flags & RTF_GATEWAY))
570                 return RT6_NUD_SUCCEED;
571
572         rcu_read_lock_bh();
573         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
574         if (neigh) {
575                 read_lock(&neigh->lock);
576                 if (neigh->nud_state & NUD_VALID)
577                         ret = RT6_NUD_SUCCEED;
578 #ifdef CONFIG_IPV6_ROUTER_PREF
579                 else if (!(neigh->nud_state & NUD_FAILED))
580                         ret = RT6_NUD_SUCCEED;
581                 else
582                         ret = RT6_NUD_FAIL_PROBE;
583 #endif
584                 read_unlock(&neigh->lock);
585         } else {
586                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
587                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
588         }
589         rcu_read_unlock_bh();
590
591         return ret;
592 }
593
594 static int rt6_score_route(struct rt6_info *rt, int oif,
595                            int strict)
596 {
597         int m;
598
599         m = rt6_check_dev(rt, oif);
600         if (!m && (strict & RT6_LOOKUP_F_IFACE))
601                 return RT6_NUD_FAIL_HARD;
602 #ifdef CONFIG_IPV6_ROUTER_PREF
603         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
604 #endif
605         if (strict & RT6_LOOKUP_F_REACHABLE) {
606                 int n = rt6_check_neigh(rt);
607                 if (n < 0)
608                         return n;
609         }
610         return m;
611 }
612
613 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
614                                    int *mpri, struct rt6_info *match,
615                                    bool *do_rr)
616 {
617         int m;
618         bool match_do_rr = false;
619
620         if (rt6_check_expired(rt))
621                 goto out;
622
623         m = rt6_score_route(rt, oif, strict);
624         if (m == RT6_NUD_FAIL_DO_RR) {
625                 match_do_rr = true;
626                 m = 0; /* lowest valid score */
627         } else if (m == RT6_NUD_FAIL_HARD) {
628                 goto out;
629         }
630
631         if (strict & RT6_LOOKUP_F_REACHABLE)
632                 rt6_probe(rt);
633
634         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
635         if (m > *mpri) {
636                 *do_rr = match_do_rr;
637                 *mpri = m;
638                 match = rt;
639         }
640 out:
641         return match;
642 }
643
644 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
645                                      struct rt6_info *rr_head,
646                                      u32 metric, int oif, int strict,
647                                      bool *do_rr)
648 {
649         struct rt6_info *rt, *match;
650         int mpri = -1;
651
652         match = NULL;
653         for (rt = rr_head; rt && rt->rt6i_metric == metric;
654              rt = rt->dst.rt6_next)
655                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
656         for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
657              rt = rt->dst.rt6_next)
658                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
659
660         return match;
661 }
662
663 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
664 {
665         struct rt6_info *match, *rt0;
666         struct net *net;
667         bool do_rr = false;
668
669         rt0 = fn->rr_ptr;
670         if (!rt0)
671                 fn->rr_ptr = rt0 = fn->leaf;
672
673         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
674                              &do_rr);
675
676         if (do_rr) {
677                 struct rt6_info *next = rt0->dst.rt6_next;
678
679                 /* no entries matched; do round-robin */
680                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
681                         next = fn->leaf;
682
683                 if (next != rt0)
684                         fn->rr_ptr = next;
685         }
686
687         net = dev_net(rt0->dst.dev);
688         return match ? match : net->ipv6.ip6_null_entry;
689 }
690
691 #ifdef CONFIG_IPV6_ROUTE_INFO
692 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
693                   const struct in6_addr *gwaddr)
694 {
695         struct net *net = dev_net(dev);
696         struct route_info *rinfo = (struct route_info *) opt;
697         struct in6_addr prefix_buf, *prefix;
698         unsigned int pref;
699         unsigned long lifetime;
700         struct rt6_info *rt;
701
702         if (len < sizeof(struct route_info)) {
703                 return -EINVAL;
704         }
705
706         /* Sanity check for prefix_len and length */
707         if (rinfo->length > 3) {
708                 return -EINVAL;
709         } else if (rinfo->prefix_len > 128) {
710                 return -EINVAL;
711         } else if (rinfo->prefix_len > 64) {
712                 if (rinfo->length < 2) {
713                         return -EINVAL;
714                 }
715         } else if (rinfo->prefix_len > 0) {
716                 if (rinfo->length < 1) {
717                         return -EINVAL;
718                 }
719         }
720
721         pref = rinfo->route_pref;
722         if (pref == ICMPV6_ROUTER_PREF_INVALID)
723                 return -EINVAL;
724
725         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
726
727         if (rinfo->length == 3)
728                 prefix = (struct in6_addr *)rinfo->prefix;
729         else {
730                 /* this function is safe */
731                 ipv6_addr_prefix(&prefix_buf,
732                                  (struct in6_addr *)rinfo->prefix,
733                                  rinfo->prefix_len);
734                 prefix = &prefix_buf;
735         }
736
737         if (rinfo->prefix_len == 0)
738                 rt = rt6_get_dflt_router(gwaddr, dev);
739         else
740                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
741                                         gwaddr, dev->ifindex);
742
743         if (rt && !lifetime) {
744                 ip6_del_rt(rt);
745                 rt = NULL;
746         }
747
748         if (!rt && lifetime)
749                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
750                                         pref);
751         else if (rt)
752                 rt->rt6i_flags = RTF_ROUTEINFO |
753                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
754
755         if (rt) {
756                 if (!addrconf_finite_timeout(lifetime))
757                         rt6_clean_expires(rt);
758                 else
759                         rt6_set_expires(rt, jiffies + HZ * lifetime);
760
761                 ip6_rt_put(rt);
762         }
763         return 0;
764 }
765 #endif
766
767 #define BACKTRACK(__net, saddr)                 \
768 do { \
769         if (rt == __net->ipv6.ip6_null_entry) { \
770                 struct fib6_node *pn; \
771                 while (1) { \
772                         if (fn->fn_flags & RTN_TL_ROOT) \
773                                 goto out; \
774                         pn = fn->parent; \
775                         if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
776                                 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
777                         else \
778                                 fn = pn; \
779                         if (fn->fn_flags & RTN_RTINFO) \
780                                 goto restart; \
781                 } \
782         } \
783 } while (0)
784
785 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
786                                              struct fib6_table *table,
787                                              struct flowi6 *fl6, int flags)
788 {
789         struct fib6_node *fn;
790         struct rt6_info *rt;
791
792         read_lock_bh(&table->tb6_lock);
793         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
794 restart:
795         rt = fn->leaf;
796         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
797         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
798                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
799         BACKTRACK(net, &fl6->saddr);
800 out:
801         dst_use(&rt->dst, jiffies);
802         read_unlock_bh(&table->tb6_lock);
803         return rt;
804
805 }
806
807 struct dst_entry * ip6_route_lookup(struct net *net, struct flowi6 *fl6,
808                                     int flags)
809 {
810         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
811 }
812 EXPORT_SYMBOL_GPL(ip6_route_lookup);
813
814 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
815                             const struct in6_addr *saddr, int oif, int strict)
816 {
817         struct flowi6 fl6 = {
818                 .flowi6_oif = oif,
819                 .daddr = *daddr,
820         };
821         struct dst_entry *dst;
822         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
823
824         if (saddr) {
825                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
826                 flags |= RT6_LOOKUP_F_HAS_SADDR;
827         }
828
829         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
830         if (dst->error == 0)
831                 return (struct rt6_info *) dst;
832
833         dst_release(dst);
834
835         return NULL;
836 }
837
838 EXPORT_SYMBOL(rt6_lookup);
839
840 /* ip6_ins_rt is called with FREE table->tb6_lock.
841    It takes new route entry, the addition fails by any reason the
842    route is freed. In any case, if caller does not hold it, it may
843    be destroyed.
844  */
845
846 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
847 {
848         int err;
849         struct fib6_table *table;
850
851         table = rt->rt6i_table;
852         write_lock_bh(&table->tb6_lock);
853         err = fib6_add(&table->tb6_root, rt, info);
854         write_unlock_bh(&table->tb6_lock);
855
856         return err;
857 }
858
859 int ip6_ins_rt(struct rt6_info *rt)
860 {
861         struct nl_info info = {
862                 .nl_net = dev_net(rt->dst.dev),
863         };
864         return __ip6_ins_rt(rt, &info);
865 }
866
867 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort,
868                                       const struct in6_addr *daddr,
869                                       const struct in6_addr *saddr)
870 {
871         struct rt6_info *rt;
872
873         /*
874          *      Clone the route.
875          */
876
877         rt = ip6_rt_copy(ort, daddr);
878
879         if (rt) {
880                 if (ort->rt6i_dst.plen != 128 &&
881                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
882                         rt->rt6i_flags |= RTF_ANYCAST;
883
884                 rt->rt6i_flags |= RTF_CACHE;
885
886 #ifdef CONFIG_IPV6_SUBTREES
887                 if (rt->rt6i_src.plen && saddr) {
888                         rt->rt6i_src.addr = *saddr;
889                         rt->rt6i_src.plen = 128;
890                 }
891 #endif
892         }
893
894         return rt;
895 }
896
897 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort,
898                                         const struct in6_addr *daddr)
899 {
900         struct rt6_info *rt = ip6_rt_copy(ort, daddr);
901
902         if (rt)
903                 rt->rt6i_flags |= RTF_CACHE;
904         return rt;
905 }
906
907 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
908                                       struct flowi6 *fl6, int flags)
909 {
910         struct fib6_node *fn;
911         struct rt6_info *rt, *nrt;
912         int strict = 0;
913         int attempts = 3;
914         int err;
915         int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
916
917         strict |= flags & RT6_LOOKUP_F_IFACE;
918
919 relookup:
920         read_lock_bh(&table->tb6_lock);
921
922 restart_2:
923         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
924
925 restart:
926         rt = rt6_select(fn, oif, strict | reachable);
927         if (rt->rt6i_nsiblings)
928                 rt = rt6_multipath_select(rt, fl6, oif, strict | reachable);
929         BACKTRACK(net, &fl6->saddr);
930         if (rt == net->ipv6.ip6_null_entry ||
931             rt->rt6i_flags & RTF_CACHE)
932                 goto out;
933
934         dst_hold(&rt->dst);
935         read_unlock_bh(&table->tb6_lock);
936
937         if (!(rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY)))
938                 nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
939         else if (!(rt->dst.flags & DST_HOST))
940                 nrt = rt6_alloc_clone(rt, &fl6->daddr);
941         else
942                 goto out2;
943
944         ip6_rt_put(rt);
945         rt = nrt ? : net->ipv6.ip6_null_entry;
946
947         dst_hold(&rt->dst);
948         if (nrt) {
949                 err = ip6_ins_rt(nrt);
950                 if (!err)
951                         goto out2;
952         }
953
954         if (--attempts <= 0)
955                 goto out2;
956
957         /*
958          * Race condition! In the gap, when table->tb6_lock was
959          * released someone could insert this route.  Relookup.
960          */
961         ip6_rt_put(rt);
962         goto relookup;
963
964 out:
965         if (reachable) {
966                 reachable = 0;
967                 goto restart_2;
968         }
969         dst_hold(&rt->dst);
970         read_unlock_bh(&table->tb6_lock);
971 out2:
972         rt->dst.lastuse = jiffies;
973         rt->dst.__use++;
974
975         return rt;
976 }
977
978 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
979                                             struct flowi6 *fl6, int flags)
980 {
981         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
982 }
983
984 static struct dst_entry *ip6_route_input_lookup(struct net *net,
985                                                 struct net_device *dev,
986                                                 struct flowi6 *fl6, int flags)
987 {
988         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
989                 flags |= RT6_LOOKUP_F_IFACE;
990
991         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
992 }
993
994 void ip6_route_input(struct sk_buff *skb)
995 {
996         const struct ipv6hdr *iph = ipv6_hdr(skb);
997         struct net *net = dev_net(skb->dev);
998         int flags = RT6_LOOKUP_F_HAS_SADDR;
999         struct flowi6 fl6 = {
1000                 .flowi6_iif = skb->dev->ifindex,
1001                 .daddr = iph->daddr,
1002                 .saddr = iph->saddr,
1003                 .flowlabel = ip6_flowinfo(iph),
1004                 .flowi6_mark = skb->mark,
1005                 .flowi6_proto = iph->nexthdr,
1006         };
1007
1008         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1009 }
1010
1011 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1012                                              struct flowi6 *fl6, int flags)
1013 {
1014         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1015 }
1016
1017 struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
1018                                     struct flowi6 *fl6)
1019 {
1020         int flags = 0;
1021
1022         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1023
1024         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
1025                 flags |= RT6_LOOKUP_F_IFACE;
1026
1027         if (!ipv6_addr_any(&fl6->saddr))
1028                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1029         else if (sk)
1030                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1031
1032         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1033 }
1034
1035 EXPORT_SYMBOL(ip6_route_output);
1036
1037 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1038 {
1039         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1040         struct dst_entry *new = NULL;
1041
1042         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1043         if (rt) {
1044                 new = &rt->dst;
1045
1046                 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1047                 rt6_init_peer(rt, net->ipv6.peers);
1048
1049                 new->__use = 1;
1050                 new->input = dst_discard;
1051                 new->output = dst_discard;
1052
1053                 if (dst_metrics_read_only(&ort->dst))
1054                         new->_metrics = ort->dst._metrics;
1055                 else
1056                         dst_copy_metrics(new, &ort->dst);
1057                 rt->rt6i_idev = ort->rt6i_idev;
1058                 if (rt->rt6i_idev)
1059                         in6_dev_hold(rt->rt6i_idev);
1060
1061                 rt->rt6i_gateway = ort->rt6i_gateway;
1062                 rt->rt6i_flags = ort->rt6i_flags;
1063                 rt->rt6i_metric = 0;
1064
1065                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1066 #ifdef CONFIG_IPV6_SUBTREES
1067                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1068 #endif
1069
1070                 dst_free(new);
1071         }
1072
1073         dst_release(dst_orig);
1074         return new ? new : ERR_PTR(-ENOMEM);
1075 }
1076
1077 /*
1078  *      Destination cache support functions
1079  */
1080
1081 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1082 {
1083         struct rt6_info *rt;
1084
1085         rt = (struct rt6_info *) dst;
1086
1087         /* All IPV6 dsts are created with ->obsolete set to the value
1088          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1089          * into this function always.
1090          */
1091         if (rt->rt6i_genid != rt_genid_ipv6(dev_net(rt->dst.dev)))
1092                 return NULL;
1093
1094         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1095                 return NULL;
1096
1097         if (rt6_check_expired(rt))
1098                 return NULL;
1099
1100         return dst;
1101 }
1102
1103 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1104 {
1105         struct rt6_info *rt = (struct rt6_info *) dst;
1106
1107         if (rt) {
1108                 if (rt->rt6i_flags & RTF_CACHE) {
1109                         if (rt6_check_expired(rt)) {
1110                                 ip6_del_rt(rt);
1111                                 dst = NULL;
1112                         }
1113                 } else {
1114                         dst_release(dst);
1115                         dst = NULL;
1116                 }
1117         }
1118         return dst;
1119 }
1120
1121 static void ip6_link_failure(struct sk_buff *skb)
1122 {
1123         struct rt6_info *rt;
1124
1125         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1126
1127         rt = (struct rt6_info *) skb_dst(skb);
1128         if (rt) {
1129                 if (rt->rt6i_flags & RTF_CACHE) {
1130                         dst_hold(&rt->dst);
1131                         if (ip6_del_rt(rt))
1132                                 dst_free(&rt->dst);
1133                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1134                         rt->rt6i_node->fn_sernum = -1;
1135                 }
1136         }
1137 }
1138
1139 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1140                                struct sk_buff *skb, u32 mtu)
1141 {
1142         struct rt6_info *rt6 = (struct rt6_info*)dst;
1143
1144         dst_confirm(dst);
1145         if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
1146                 struct net *net = dev_net(dst->dev);
1147
1148                 rt6->rt6i_flags |= RTF_MODIFIED;
1149                 if (mtu < IPV6_MIN_MTU) {
1150                         u32 features = dst_metric(dst, RTAX_FEATURES);
1151                         mtu = IPV6_MIN_MTU;
1152                         features |= RTAX_FEATURE_ALLFRAG;
1153                         dst_metric_set(dst, RTAX_FEATURES, features);
1154                 }
1155                 dst_metric_set(dst, RTAX_MTU, mtu);
1156                 rt6_update_expires(rt6, net->ipv6.sysctl.ip6_rt_mtu_expires);
1157         }
1158 }
1159
1160 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1161                      int oif, u32 mark)
1162 {
1163         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1164         struct dst_entry *dst;
1165         struct flowi6 fl6;
1166
1167         memset(&fl6, 0, sizeof(fl6));
1168         fl6.flowi6_oif = oif;
1169         fl6.flowi6_mark = mark;
1170         fl6.daddr = iph->daddr;
1171         fl6.saddr = iph->saddr;
1172         fl6.flowlabel = ip6_flowinfo(iph);
1173
1174         dst = ip6_route_output(net, NULL, &fl6);
1175         if (!dst->error)
1176                 ip6_rt_update_pmtu(dst, NULL, skb, ntohl(mtu));
1177         dst_release(dst);
1178 }
1179 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1180
1181 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1182 {
1183         ip6_update_pmtu(skb, sock_net(sk), mtu,
1184                         sk->sk_bound_dev_if, sk->sk_mark);
1185 }
1186 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1187
1188 /* Handle redirects */
1189 struct ip6rd_flowi {
1190         struct flowi6 fl6;
1191         struct in6_addr gateway;
1192 };
1193
1194 static struct rt6_info *__ip6_route_redirect(struct net *net,
1195                                              struct fib6_table *table,
1196                                              struct flowi6 *fl6,
1197                                              int flags)
1198 {
1199         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1200         struct rt6_info *rt;
1201         struct fib6_node *fn;
1202
1203         /* Get the "current" route for this destination and
1204          * check if the redirect has come from approriate router.
1205          *
1206          * RFC 4861 specifies that redirects should only be
1207          * accepted if they come from the nexthop to the target.
1208          * Due to the way the routes are chosen, this notion
1209          * is a bit fuzzy and one might need to check all possible
1210          * routes.
1211          */
1212
1213         read_lock_bh(&table->tb6_lock);
1214         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1215 restart:
1216         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1217                 if (rt6_check_expired(rt))
1218                         continue;
1219                 if (rt->dst.error)
1220                         break;
1221                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1222                         continue;
1223                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1224                         continue;
1225                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1226                         continue;
1227                 break;
1228         }
1229
1230         if (!rt)
1231                 rt = net->ipv6.ip6_null_entry;
1232         else if (rt->dst.error) {
1233                 rt = net->ipv6.ip6_null_entry;
1234                 goto out;
1235         }
1236         BACKTRACK(net, &fl6->saddr);
1237 out:
1238         dst_hold(&rt->dst);
1239
1240         read_unlock_bh(&table->tb6_lock);
1241
1242         return rt;
1243 };
1244
1245 static struct dst_entry *ip6_route_redirect(struct net *net,
1246                                         const struct flowi6 *fl6,
1247                                         const struct in6_addr *gateway)
1248 {
1249         int flags = RT6_LOOKUP_F_HAS_SADDR;
1250         struct ip6rd_flowi rdfl;
1251
1252         rdfl.fl6 = *fl6;
1253         rdfl.gateway = *gateway;
1254
1255         return fib6_rule_lookup(net, &rdfl.fl6,
1256                                 flags, __ip6_route_redirect);
1257 }
1258
1259 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1260 {
1261         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1262         struct dst_entry *dst;
1263         struct flowi6 fl6;
1264
1265         memset(&fl6, 0, sizeof(fl6));
1266         fl6.flowi6_oif = oif;
1267         fl6.flowi6_mark = mark;
1268         fl6.daddr = iph->daddr;
1269         fl6.saddr = iph->saddr;
1270         fl6.flowlabel = ip6_flowinfo(iph);
1271
1272         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1273         rt6_do_redirect(dst, NULL, skb);
1274         dst_release(dst);
1275 }
1276 EXPORT_SYMBOL_GPL(ip6_redirect);
1277
1278 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1279                             u32 mark)
1280 {
1281         const struct ipv6hdr *iph = ipv6_hdr(skb);
1282         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1283         struct dst_entry *dst;
1284         struct flowi6 fl6;
1285
1286         memset(&fl6, 0, sizeof(fl6));
1287         fl6.flowi6_oif = oif;
1288         fl6.flowi6_mark = mark;
1289         fl6.daddr = msg->dest;
1290         fl6.saddr = iph->daddr;
1291
1292         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1293         rt6_do_redirect(dst, NULL, skb);
1294         dst_release(dst);
1295 }
1296
1297 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1298 {
1299         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1300 }
1301 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1302
1303 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1304 {
1305         struct net_device *dev = dst->dev;
1306         unsigned int mtu = dst_mtu(dst);
1307         struct net *net = dev_net(dev);
1308
1309         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1310
1311         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1312                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1313
1314         /*
1315          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1316          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1317          * IPV6_MAXPLEN is also valid and means: "any MSS,
1318          * rely only on pmtu discovery"
1319          */
1320         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1321                 mtu = IPV6_MAXPLEN;
1322         return mtu;
1323 }
1324
1325 static unsigned int ip6_mtu(const struct dst_entry *dst)
1326 {
1327         struct inet6_dev *idev;
1328         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
1329
1330         if (mtu)
1331                 return mtu;
1332
1333         mtu = IPV6_MIN_MTU;
1334
1335         rcu_read_lock();
1336         idev = __in6_dev_get(dst->dev);
1337         if (idev)
1338                 mtu = idev->cnf.mtu6;
1339         rcu_read_unlock();
1340
1341         return mtu;
1342 }
1343
1344 static struct dst_entry *icmp6_dst_gc_list;
1345 static DEFINE_SPINLOCK(icmp6_dst_lock);
1346
1347 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1348                                   struct flowi6 *fl6)
1349 {
1350         struct dst_entry *dst;
1351         struct rt6_info *rt;
1352         struct inet6_dev *idev = in6_dev_get(dev);
1353         struct net *net = dev_net(dev);
1354
1355         if (unlikely(!idev))
1356                 return ERR_PTR(-ENODEV);
1357
1358         rt = ip6_dst_alloc(net, dev, 0, NULL);
1359         if (unlikely(!rt)) {
1360                 in6_dev_put(idev);
1361                 dst = ERR_PTR(-ENOMEM);
1362                 goto out;
1363         }
1364
1365         rt->dst.flags |= DST_HOST;
1366         rt->dst.output  = ip6_output;
1367         atomic_set(&rt->dst.__refcnt, 1);
1368         rt->rt6i_gateway  = fl6->daddr;
1369         rt->rt6i_dst.addr = fl6->daddr;
1370         rt->rt6i_dst.plen = 128;
1371         rt->rt6i_idev     = idev;
1372         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1373
1374         spin_lock_bh(&icmp6_dst_lock);
1375         rt->dst.next = icmp6_dst_gc_list;
1376         icmp6_dst_gc_list = &rt->dst;
1377         spin_unlock_bh(&icmp6_dst_lock);
1378
1379         fib6_force_start_gc(net);
1380
1381         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1382
1383 out:
1384         return dst;
1385 }
1386
1387 int icmp6_dst_gc(void)
1388 {
1389         struct dst_entry *dst, **pprev;
1390         int more = 0;
1391
1392         spin_lock_bh(&icmp6_dst_lock);
1393         pprev = &icmp6_dst_gc_list;
1394
1395         while ((dst = *pprev) != NULL) {
1396                 if (!atomic_read(&dst->__refcnt)) {
1397                         *pprev = dst->next;
1398                         dst_free(dst);
1399                 } else {
1400                         pprev = &dst->next;
1401                         ++more;
1402                 }
1403         }
1404
1405         spin_unlock_bh(&icmp6_dst_lock);
1406
1407         return more;
1408 }
1409
1410 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1411                             void *arg)
1412 {
1413         struct dst_entry *dst, **pprev;
1414
1415         spin_lock_bh(&icmp6_dst_lock);
1416         pprev = &icmp6_dst_gc_list;
1417         while ((dst = *pprev) != NULL) {
1418                 struct rt6_info *rt = (struct rt6_info *) dst;
1419                 if (func(rt, arg)) {
1420                         *pprev = dst->next;
1421                         dst_free(dst);
1422                 } else {
1423                         pprev = &dst->next;
1424                 }
1425         }
1426         spin_unlock_bh(&icmp6_dst_lock);
1427 }
1428
1429 static int ip6_dst_gc(struct dst_ops *ops)
1430 {
1431         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1432         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1433         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1434         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1435         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1436         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1437         int entries;
1438
1439         entries = dst_entries_get_fast(ops);
1440         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1441             entries <= rt_max_size)
1442                 goto out;
1443
1444         net->ipv6.ip6_rt_gc_expire++;
1445         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, entries > rt_max_size);
1446         entries = dst_entries_get_slow(ops);
1447         if (entries < ops->gc_thresh)
1448                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1449 out:
1450         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1451         return entries > rt_max_size;
1452 }
1453
1454 /*
1455  *
1456  */
1457
1458 int ip6_route_add(struct fib6_config *cfg)
1459 {
1460         int err;
1461         struct net *net = cfg->fc_nlinfo.nl_net;
1462         struct rt6_info *rt = NULL;
1463         struct net_device *dev = NULL;
1464         struct inet6_dev *idev = NULL;
1465         struct fib6_table *table;
1466         int addr_type;
1467
1468         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1469                 return -EINVAL;
1470 #ifndef CONFIG_IPV6_SUBTREES
1471         if (cfg->fc_src_len)
1472                 return -EINVAL;
1473 #endif
1474         if (cfg->fc_ifindex) {
1475                 err = -ENODEV;
1476                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1477                 if (!dev)
1478                         goto out;
1479                 idev = in6_dev_get(dev);
1480                 if (!idev)
1481                         goto out;
1482         }
1483
1484         if (cfg->fc_metric == 0)
1485                 cfg->fc_metric = IP6_RT_PRIO_USER;
1486
1487         err = -ENOBUFS;
1488         if (cfg->fc_nlinfo.nlh &&
1489             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1490                 table = fib6_get_table(net, cfg->fc_table);
1491                 if (!table) {
1492                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1493                         table = fib6_new_table(net, cfg->fc_table);
1494                 }
1495         } else {
1496                 table = fib6_new_table(net, cfg->fc_table);
1497         }
1498
1499         if (!table)
1500                 goto out;
1501
1502         rt = ip6_dst_alloc(net, NULL, DST_NOCOUNT, table);
1503
1504         if (!rt) {
1505                 err = -ENOMEM;
1506                 goto out;
1507         }
1508
1509         if (cfg->fc_flags & RTF_EXPIRES)
1510                 rt6_set_expires(rt, jiffies +
1511                                 clock_t_to_jiffies(cfg->fc_expires));
1512         else
1513                 rt6_clean_expires(rt);
1514
1515         if (cfg->fc_protocol == RTPROT_UNSPEC)
1516                 cfg->fc_protocol = RTPROT_BOOT;
1517         rt->rt6i_protocol = cfg->fc_protocol;
1518
1519         addr_type = ipv6_addr_type(&cfg->fc_dst);
1520
1521         if (addr_type & IPV6_ADDR_MULTICAST)
1522                 rt->dst.input = ip6_mc_input;
1523         else if (cfg->fc_flags & RTF_LOCAL)
1524                 rt->dst.input = ip6_input;
1525         else
1526                 rt->dst.input = ip6_forward;
1527
1528         rt->dst.output = ip6_output;
1529
1530         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1531         rt->rt6i_dst.plen = cfg->fc_dst_len;
1532         if (rt->rt6i_dst.plen == 128)
1533                rt->dst.flags |= DST_HOST;
1534
1535         if (!(rt->dst.flags & DST_HOST) && cfg->fc_mx) {
1536                 u32 *metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1537                 if (!metrics) {
1538                         err = -ENOMEM;
1539                         goto out;
1540                 }
1541                 dst_init_metrics(&rt->dst, metrics, 0);
1542         }
1543 #ifdef CONFIG_IPV6_SUBTREES
1544         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1545         rt->rt6i_src.plen = cfg->fc_src_len;
1546 #endif
1547
1548         rt->rt6i_metric = cfg->fc_metric;
1549
1550         /* We cannot add true routes via loopback here,
1551            they would result in kernel looping; promote them to reject routes
1552          */
1553         if ((cfg->fc_flags & RTF_REJECT) ||
1554             (dev && (dev->flags & IFF_LOOPBACK) &&
1555              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1556              !(cfg->fc_flags & RTF_LOCAL))) {
1557                 /* hold loopback dev/idev if we haven't done so. */
1558                 if (dev != net->loopback_dev) {
1559                         if (dev) {
1560                                 dev_put(dev);
1561                                 in6_dev_put(idev);
1562                         }
1563                         dev = net->loopback_dev;
1564                         dev_hold(dev);
1565                         idev = in6_dev_get(dev);
1566                         if (!idev) {
1567                                 err = -ENODEV;
1568                                 goto out;
1569                         }
1570                 }
1571                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1572                 switch (cfg->fc_type) {
1573                 case RTN_BLACKHOLE:
1574                         rt->dst.error = -EINVAL;
1575                         rt->dst.output = dst_discard;
1576                         rt->dst.input = dst_discard;
1577                         break;
1578                 case RTN_PROHIBIT:
1579                         rt->dst.error = -EACCES;
1580                         rt->dst.output = ip6_pkt_prohibit_out;
1581                         rt->dst.input = ip6_pkt_prohibit;
1582                         break;
1583                 case RTN_THROW:
1584                 default:
1585                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1586                                         : -ENETUNREACH;
1587                         rt->dst.output = ip6_pkt_discard_out;
1588                         rt->dst.input = ip6_pkt_discard;
1589                         break;
1590                 }
1591                 goto install_route;
1592         }
1593
1594         if (cfg->fc_flags & RTF_GATEWAY) {
1595                 const struct in6_addr *gw_addr;
1596                 int gwa_type;
1597
1598                 gw_addr = &cfg->fc_gateway;
1599                 rt->rt6i_gateway = *gw_addr;
1600                 gwa_type = ipv6_addr_type(gw_addr);
1601
1602                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1603                         struct rt6_info *grt;
1604
1605                         /* IPv6 strictly inhibits using not link-local
1606                            addresses as nexthop address.
1607                            Otherwise, router will not able to send redirects.
1608                            It is very good, but in some (rare!) circumstances
1609                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1610                            some exceptions. --ANK
1611                          */
1612                         err = -EINVAL;
1613                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1614                                 goto out;
1615
1616                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1617
1618                         err = -EHOSTUNREACH;
1619                         if (!grt)
1620                                 goto out;
1621                         if (dev) {
1622                                 if (dev != grt->dst.dev) {
1623                                         ip6_rt_put(grt);
1624                                         goto out;
1625                                 }
1626                         } else {
1627                                 dev = grt->dst.dev;
1628                                 idev = grt->rt6i_idev;
1629                                 dev_hold(dev);
1630                                 in6_dev_hold(grt->rt6i_idev);
1631                         }
1632                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1633                                 err = 0;
1634                         ip6_rt_put(grt);
1635
1636                         if (err)
1637                                 goto out;
1638                 }
1639                 err = -EINVAL;
1640                 if (!dev || (dev->flags & IFF_LOOPBACK))
1641                         goto out;
1642         }
1643
1644         err = -ENODEV;
1645         if (!dev)
1646                 goto out;
1647
1648         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1649                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1650                         err = -EINVAL;
1651                         goto out;
1652                 }
1653                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1654                 rt->rt6i_prefsrc.plen = 128;
1655         } else
1656                 rt->rt6i_prefsrc.plen = 0;
1657
1658         rt->rt6i_flags = cfg->fc_flags;
1659
1660 install_route:
1661         if (cfg->fc_mx) {
1662                 struct nlattr *nla;
1663                 int remaining;
1664
1665                 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1666                         int type = nla_type(nla);
1667
1668                         if (type) {
1669                                 if (type > RTAX_MAX) {
1670                                         err = -EINVAL;
1671                                         goto out;
1672                                 }
1673
1674                                 dst_metric_set(&rt->dst, type, nla_get_u32(nla));
1675                         }
1676                 }
1677         }
1678
1679         rt->dst.dev = dev;
1680         rt->rt6i_idev = idev;
1681         rt->rt6i_table = table;
1682
1683         cfg->fc_nlinfo.nl_net = dev_net(dev);
1684
1685         return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1686
1687 out:
1688         if (dev)
1689                 dev_put(dev);
1690         if (idev)
1691                 in6_dev_put(idev);
1692         if (rt)
1693                 dst_free(&rt->dst);
1694         return err;
1695 }
1696
1697 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1698 {
1699         int err;
1700         struct fib6_table *table;
1701         struct net *net = dev_net(rt->dst.dev);
1702
1703         if (rt == net->ipv6.ip6_null_entry) {
1704                 err = -ENOENT;
1705                 goto out;
1706         }
1707
1708         table = rt->rt6i_table;
1709         write_lock_bh(&table->tb6_lock);
1710         err = fib6_del(rt, info);
1711         write_unlock_bh(&table->tb6_lock);
1712
1713 out:
1714         ip6_rt_put(rt);
1715         return err;
1716 }
1717
1718 int ip6_del_rt(struct rt6_info *rt)
1719 {
1720         struct nl_info info = {
1721                 .nl_net = dev_net(rt->dst.dev),
1722         };
1723         return __ip6_del_rt(rt, &info);
1724 }
1725
1726 static int ip6_route_del(struct fib6_config *cfg)
1727 {
1728         struct fib6_table *table;
1729         struct fib6_node *fn;
1730         struct rt6_info *rt;
1731         int err = -ESRCH;
1732
1733         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1734         if (!table)
1735                 return err;
1736
1737         read_lock_bh(&table->tb6_lock);
1738
1739         fn = fib6_locate(&table->tb6_root,
1740                          &cfg->fc_dst, cfg->fc_dst_len,
1741                          &cfg->fc_src, cfg->fc_src_len);
1742
1743         if (fn) {
1744                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1745                         if (cfg->fc_ifindex &&
1746                             (!rt->dst.dev ||
1747                              rt->dst.dev->ifindex != cfg->fc_ifindex))
1748                                 continue;
1749                         if (cfg->fc_flags & RTF_GATEWAY &&
1750                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1751                                 continue;
1752                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1753                                 continue;
1754                         dst_hold(&rt->dst);
1755                         read_unlock_bh(&table->tb6_lock);
1756
1757                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1758                 }
1759         }
1760         read_unlock_bh(&table->tb6_lock);
1761
1762         return err;
1763 }
1764
1765 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
1766 {
1767         struct net *net = dev_net(skb->dev);
1768         struct netevent_redirect netevent;
1769         struct rt6_info *rt, *nrt = NULL;
1770         struct ndisc_options ndopts;
1771         struct inet6_dev *in6_dev;
1772         struct neighbour *neigh;
1773         struct rd_msg *msg;
1774         int optlen, on_link;
1775         u8 *lladdr;
1776
1777         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1778         optlen -= sizeof(*msg);
1779
1780         if (optlen < 0) {
1781                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
1782                 return;
1783         }
1784
1785         msg = (struct rd_msg *)icmp6_hdr(skb);
1786
1787         if (ipv6_addr_is_multicast(&msg->dest)) {
1788                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
1789                 return;
1790         }
1791
1792         on_link = 0;
1793         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
1794                 on_link = 1;
1795         } else if (ipv6_addr_type(&msg->target) !=
1796                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1797                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
1798                 return;
1799         }
1800
1801         in6_dev = __in6_dev_get(skb->dev);
1802         if (!in6_dev)
1803                 return;
1804         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
1805                 return;
1806
1807         /* RFC2461 8.1:
1808          *      The IP source address of the Redirect MUST be the same as the current
1809          *      first-hop router for the specified ICMP Destination Address.
1810          */
1811
1812         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
1813                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
1814                 return;
1815         }
1816
1817         lladdr = NULL;
1818         if (ndopts.nd_opts_tgt_lladdr) {
1819                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1820                                              skb->dev);
1821                 if (!lladdr) {
1822                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
1823                         return;
1824                 }
1825         }
1826
1827         rt = (struct rt6_info *) dst;
1828         if (rt == net->ipv6.ip6_null_entry) {
1829                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
1830                 return;
1831         }
1832
1833         /* Redirect received -> path was valid.
1834          * Look, redirects are sent only in response to data packets,
1835          * so that this nexthop apparently is reachable. --ANK
1836          */
1837         dst_confirm(&rt->dst);
1838
1839         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
1840         if (!neigh)
1841                 return;
1842
1843         /*
1844          *      We have finally decided to accept it.
1845          */
1846
1847         neigh_update(neigh, lladdr, NUD_STALE,
1848                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
1849                      NEIGH_UPDATE_F_OVERRIDE|
1850                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1851                                      NEIGH_UPDATE_F_ISROUTER))
1852                      );
1853
1854         nrt = ip6_rt_copy(rt, &msg->dest);
1855         if (!nrt)
1856                 goto out;
1857
1858         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1859         if (on_link)
1860                 nrt->rt6i_flags &= ~RTF_GATEWAY;
1861
1862         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
1863
1864         if (ip6_ins_rt(nrt))
1865                 goto out;
1866
1867         netevent.old = &rt->dst;
1868         netevent.new = &nrt->dst;
1869         netevent.daddr = &msg->dest;
1870         netevent.neigh = neigh;
1871         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1872
1873         if (rt->rt6i_flags & RTF_CACHE) {
1874                 rt = (struct rt6_info *) dst_clone(&rt->dst);
1875                 ip6_del_rt(rt);
1876         }
1877
1878 out:
1879         neigh_release(neigh);
1880 }
1881
1882 /*
1883  *      Misc support functions
1884  */
1885
1886 static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
1887                                     const struct in6_addr *dest)
1888 {
1889         struct net *net = dev_net(ort->dst.dev);
1890         struct rt6_info *rt = ip6_dst_alloc(net, ort->dst.dev, 0,
1891                                             ort->rt6i_table);
1892
1893         if (rt) {
1894                 rt->dst.input = ort->dst.input;
1895                 rt->dst.output = ort->dst.output;
1896                 rt->dst.flags |= DST_HOST;
1897
1898                 rt->rt6i_dst.addr = *dest;
1899                 rt->rt6i_dst.plen = 128;
1900                 dst_copy_metrics(&rt->dst, &ort->dst);
1901                 rt->dst.error = ort->dst.error;
1902                 rt->rt6i_idev = ort->rt6i_idev;
1903                 if (rt->rt6i_idev)
1904                         in6_dev_hold(rt->rt6i_idev);
1905                 rt->dst.lastuse = jiffies;
1906
1907                 if (ort->rt6i_flags & RTF_GATEWAY)
1908                         rt->rt6i_gateway = ort->rt6i_gateway;
1909                 else
1910                         rt->rt6i_gateway = *dest;
1911                 rt->rt6i_flags = ort->rt6i_flags;
1912                 if ((ort->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) ==
1913                     (RTF_DEFAULT | RTF_ADDRCONF))
1914                         rt6_set_from(rt, ort);
1915                 rt->rt6i_metric = 0;
1916
1917 #ifdef CONFIG_IPV6_SUBTREES
1918                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1919 #endif
1920                 memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key));
1921                 rt->rt6i_table = ort->rt6i_table;
1922         }
1923         return rt;
1924 }
1925
1926 #ifdef CONFIG_IPV6_ROUTE_INFO
1927 static struct rt6_info *rt6_get_route_info(struct net *net,
1928                                            const struct in6_addr *prefix, int prefixlen,
1929                                            const struct in6_addr *gwaddr, int ifindex)
1930 {
1931         struct fib6_node *fn;
1932         struct rt6_info *rt = NULL;
1933         struct fib6_table *table;
1934
1935         table = fib6_get_table(net, RT6_TABLE_INFO);
1936         if (!table)
1937                 return NULL;
1938
1939         read_lock_bh(&table->tb6_lock);
1940         fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1941         if (!fn)
1942                 goto out;
1943
1944         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1945                 if (rt->dst.dev->ifindex != ifindex)
1946                         continue;
1947                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1948                         continue;
1949                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1950                         continue;
1951                 dst_hold(&rt->dst);
1952                 break;
1953         }
1954 out:
1955         read_unlock_bh(&table->tb6_lock);
1956         return rt;
1957 }
1958
1959 static struct rt6_info *rt6_add_route_info(struct net *net,
1960                                            const struct in6_addr *prefix, int prefixlen,
1961                                            const struct in6_addr *gwaddr, int ifindex,
1962                                            unsigned int pref)
1963 {
1964         struct fib6_config cfg = {
1965                 .fc_table       = RT6_TABLE_INFO,
1966                 .fc_metric      = IP6_RT_PRIO_USER,
1967                 .fc_ifindex     = ifindex,
1968                 .fc_dst_len     = prefixlen,
1969                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1970                                   RTF_UP | RTF_PREF(pref),
1971                 .fc_nlinfo.portid = 0,
1972                 .fc_nlinfo.nlh = NULL,
1973                 .fc_nlinfo.nl_net = net,
1974         };
1975
1976         cfg.fc_dst = *prefix;
1977         cfg.fc_gateway = *gwaddr;
1978
1979         /* We should treat it as a default route if prefix length is 0. */
1980         if (!prefixlen)
1981                 cfg.fc_flags |= RTF_DEFAULT;
1982
1983         ip6_route_add(&cfg);
1984
1985         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1986 }
1987 #endif
1988
1989 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
1990 {
1991         struct rt6_info *rt;
1992         struct fib6_table *table;
1993
1994         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1995         if (!table)
1996                 return NULL;
1997
1998         read_lock_bh(&table->tb6_lock);
1999         for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
2000                 if (dev == rt->dst.dev &&
2001                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2002                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2003                         break;
2004         }
2005         if (rt)
2006                 dst_hold(&rt->dst);
2007         read_unlock_bh(&table->tb6_lock);
2008         return rt;
2009 }
2010
2011 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2012                                      struct net_device *dev,
2013                                      unsigned int pref)
2014 {
2015         struct fib6_config cfg = {
2016                 .fc_table       = RT6_TABLE_DFLT,
2017                 .fc_metric      = IP6_RT_PRIO_USER,
2018                 .fc_ifindex     = dev->ifindex,
2019                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2020                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2021                 .fc_nlinfo.portid = 0,
2022                 .fc_nlinfo.nlh = NULL,
2023                 .fc_nlinfo.nl_net = dev_net(dev),
2024         };
2025
2026         cfg.fc_gateway = *gwaddr;
2027
2028         ip6_route_add(&cfg);
2029
2030         return rt6_get_dflt_router(gwaddr, dev);
2031 }
2032
2033 void rt6_purge_dflt_routers(struct net *net)
2034 {
2035         struct rt6_info *rt;
2036         struct fib6_table *table;
2037
2038         /* NOTE: Keep consistent with rt6_get_dflt_router */
2039         table = fib6_get_table(net, RT6_TABLE_DFLT);
2040         if (!table)
2041                 return;
2042
2043 restart:
2044         read_lock_bh(&table->tb6_lock);
2045         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2046                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2047                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2048                         dst_hold(&rt->dst);
2049                         read_unlock_bh(&table->tb6_lock);
2050                         ip6_del_rt(rt);
2051                         goto restart;
2052                 }
2053         }
2054         read_unlock_bh(&table->tb6_lock);
2055 }
2056
2057 static void rtmsg_to_fib6_config(struct net *net,
2058                                  struct in6_rtmsg *rtmsg,
2059                                  struct fib6_config *cfg)
2060 {
2061         memset(cfg, 0, sizeof(*cfg));
2062
2063         cfg->fc_table = RT6_TABLE_MAIN;
2064         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2065         cfg->fc_metric = rtmsg->rtmsg_metric;
2066         cfg->fc_expires = rtmsg->rtmsg_info;
2067         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2068         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2069         cfg->fc_flags = rtmsg->rtmsg_flags;
2070
2071         cfg->fc_nlinfo.nl_net = net;
2072
2073         cfg->fc_dst = rtmsg->rtmsg_dst;
2074         cfg->fc_src = rtmsg->rtmsg_src;
2075         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2076 }
2077
2078 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2079 {
2080         struct fib6_config cfg;
2081         struct in6_rtmsg rtmsg;
2082         int err;
2083
2084         switch(cmd) {
2085         case SIOCADDRT:         /* Add a route */
2086         case SIOCDELRT:         /* Delete a route */
2087                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2088                         return -EPERM;
2089                 err = copy_from_user(&rtmsg, arg,
2090                                      sizeof(struct in6_rtmsg));
2091                 if (err)
2092                         return -EFAULT;
2093
2094                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2095
2096                 rtnl_lock();
2097                 switch (cmd) {
2098                 case SIOCADDRT:
2099                         err = ip6_route_add(&cfg);
2100                         break;
2101                 case SIOCDELRT:
2102                         err = ip6_route_del(&cfg);
2103                         break;
2104                 default:
2105                         err = -EINVAL;
2106                 }
2107                 rtnl_unlock();
2108
2109                 return err;
2110         }
2111
2112         return -EINVAL;
2113 }
2114
2115 /*
2116  *      Drop the packet on the floor
2117  */
2118
2119 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2120 {
2121         int type;
2122         struct dst_entry *dst = skb_dst(skb);
2123         switch (ipstats_mib_noroutes) {
2124         case IPSTATS_MIB_INNOROUTES:
2125                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2126                 if (type == IPV6_ADDR_ANY) {
2127                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2128                                       IPSTATS_MIB_INADDRERRORS);
2129                         break;
2130                 }
2131                 /* FALLTHROUGH */
2132         case IPSTATS_MIB_OUTNOROUTES:
2133                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2134                               ipstats_mib_noroutes);
2135                 break;
2136         }
2137         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2138         kfree_skb(skb);
2139         return 0;
2140 }
2141
2142 static int ip6_pkt_discard(struct sk_buff *skb)
2143 {
2144         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2145 }
2146
2147 static int ip6_pkt_discard_out(struct sk_buff *skb)
2148 {
2149         skb->dev = skb_dst(skb)->dev;
2150         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2151 }
2152
2153 static int ip6_pkt_prohibit(struct sk_buff *skb)
2154 {
2155         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2156 }
2157
2158 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
2159 {
2160         skb->dev = skb_dst(skb)->dev;
2161         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2162 }
2163
2164 /*
2165  *      Allocate a dst for local (unicast / anycast) address.
2166  */
2167
2168 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2169                                     const struct in6_addr *addr,
2170                                     bool anycast)
2171 {
2172         struct net *net = dev_net(idev->dev);
2173         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2174                                             DST_NOCOUNT, NULL);
2175         if (!rt)
2176                 return ERR_PTR(-ENOMEM);
2177
2178         in6_dev_hold(idev);
2179
2180         rt->dst.flags |= DST_HOST;
2181         rt->dst.input = ip6_input;
2182         rt->dst.output = ip6_output;
2183         rt->rt6i_idev = idev;
2184
2185         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2186         if (anycast)
2187                 rt->rt6i_flags |= RTF_ANYCAST;
2188         else
2189                 rt->rt6i_flags |= RTF_LOCAL;
2190
2191         rt->rt6i_gateway  = *addr;
2192         rt->rt6i_dst.addr = *addr;
2193         rt->rt6i_dst.plen = 128;
2194         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2195
2196         atomic_set(&rt->dst.__refcnt, 1);
2197
2198         return rt;
2199 }
2200
2201 int ip6_route_get_saddr(struct net *net,
2202                         struct rt6_info *rt,
2203                         const struct in6_addr *daddr,
2204                         unsigned int prefs,
2205                         struct in6_addr *saddr)
2206 {
2207         struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt);
2208         int err = 0;
2209         if (rt->rt6i_prefsrc.plen)
2210                 *saddr = rt->rt6i_prefsrc.addr;
2211         else
2212                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2213                                          daddr, prefs, saddr);
2214         return err;
2215 }
2216
2217 /* remove deleted ip from prefsrc entries */
2218 struct arg_dev_net_ip {
2219         struct net_device *dev;
2220         struct net *net;
2221         struct in6_addr *addr;
2222 };
2223
2224 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2225 {
2226         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2227         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2228         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2229
2230         if (((void *)rt->dst.dev == dev || !dev) &&
2231             rt != net->ipv6.ip6_null_entry &&
2232             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2233                 /* remove prefsrc entry */
2234                 rt->rt6i_prefsrc.plen = 0;
2235         }
2236         return 0;
2237 }
2238
2239 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2240 {
2241         struct net *net = dev_net(ifp->idev->dev);
2242         struct arg_dev_net_ip adni = {
2243                 .dev = ifp->idev->dev,
2244                 .net = net,
2245                 .addr = &ifp->addr,
2246         };
2247         fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni);
2248 }
2249
2250 struct arg_dev_net {
2251         struct net_device *dev;
2252         struct net *net;
2253 };
2254
2255 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2256 {
2257         const struct arg_dev_net *adn = arg;
2258         const struct net_device *dev = adn->dev;
2259
2260         if ((rt->dst.dev == dev || !dev) &&
2261             rt != adn->net->ipv6.ip6_null_entry)
2262                 return -1;
2263
2264         return 0;
2265 }
2266
2267 void rt6_ifdown(struct net *net, struct net_device *dev)
2268 {
2269         struct arg_dev_net adn = {
2270                 .dev = dev,
2271                 .net = net,
2272         };
2273
2274         fib6_clean_all(net, fib6_ifdown, 0, &adn);
2275         icmp6_clean_all(fib6_ifdown, &adn);
2276 }
2277
2278 struct rt6_mtu_change_arg {
2279         struct net_device *dev;
2280         unsigned int mtu;
2281 };
2282
2283 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2284 {
2285         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2286         struct inet6_dev *idev;
2287
2288         /* In IPv6 pmtu discovery is not optional,
2289            so that RTAX_MTU lock cannot disable it.
2290            We still use this lock to block changes
2291            caused by addrconf/ndisc.
2292         */
2293
2294         idev = __in6_dev_get(arg->dev);
2295         if (!idev)
2296                 return 0;
2297
2298         /* For administrative MTU increase, there is no way to discover
2299            IPv6 PMTU increase, so PMTU increase should be updated here.
2300            Since RFC 1981 doesn't include administrative MTU increase
2301            update PMTU increase is a MUST. (i.e. jumbo frame)
2302          */
2303         /*
2304            If new MTU is less than route PMTU, this new MTU will be the
2305            lowest MTU in the path, update the route PMTU to reflect PMTU
2306            decreases; if new MTU is greater than route PMTU, and the
2307            old MTU is the lowest MTU in the path, update the route PMTU
2308            to reflect the increase. In this case if the other nodes' MTU
2309            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2310            PMTU discouvery.
2311          */
2312         if (rt->dst.dev == arg->dev &&
2313             !dst_metric_locked(&rt->dst, RTAX_MTU) &&
2314             (dst_mtu(&rt->dst) >= arg->mtu ||
2315              (dst_mtu(&rt->dst) < arg->mtu &&
2316               dst_mtu(&rt->dst) == idev->cnf.mtu6))) {
2317                 dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2318         }
2319         return 0;
2320 }
2321
2322 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2323 {
2324         struct rt6_mtu_change_arg arg = {
2325                 .dev = dev,
2326                 .mtu = mtu,
2327         };
2328
2329         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
2330 }
2331
2332 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2333         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2334         [RTA_OIF]               = { .type = NLA_U32 },
2335         [RTA_IIF]               = { .type = NLA_U32 },
2336         [RTA_PRIORITY]          = { .type = NLA_U32 },
2337         [RTA_METRICS]           = { .type = NLA_NESTED },
2338         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2339 };
2340
2341 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2342                               struct fib6_config *cfg)
2343 {
2344         struct rtmsg *rtm;
2345         struct nlattr *tb[RTA_MAX+1];
2346         int err;
2347
2348         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2349         if (err < 0)
2350                 goto errout;
2351
2352         err = -EINVAL;
2353         rtm = nlmsg_data(nlh);
2354         memset(cfg, 0, sizeof(*cfg));
2355
2356         cfg->fc_table = rtm->rtm_table;
2357         cfg->fc_dst_len = rtm->rtm_dst_len;
2358         cfg->fc_src_len = rtm->rtm_src_len;
2359         cfg->fc_flags = RTF_UP;
2360         cfg->fc_protocol = rtm->rtm_protocol;
2361         cfg->fc_type = rtm->rtm_type;
2362
2363         if (rtm->rtm_type == RTN_UNREACHABLE ||
2364             rtm->rtm_type == RTN_BLACKHOLE ||
2365             rtm->rtm_type == RTN_PROHIBIT ||
2366             rtm->rtm_type == RTN_THROW)
2367                 cfg->fc_flags |= RTF_REJECT;
2368
2369         if (rtm->rtm_type == RTN_LOCAL)
2370                 cfg->fc_flags |= RTF_LOCAL;
2371
2372         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2373         cfg->fc_nlinfo.nlh = nlh;
2374         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2375
2376         if (tb[RTA_GATEWAY]) {
2377                 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2378                 cfg->fc_flags |= RTF_GATEWAY;
2379         }
2380
2381         if (tb[RTA_DST]) {
2382                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2383
2384                 if (nla_len(tb[RTA_DST]) < plen)
2385                         goto errout;
2386
2387                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2388         }
2389
2390         if (tb[RTA_SRC]) {
2391                 int plen = (rtm->rtm_src_len + 7) >> 3;
2392
2393                 if (nla_len(tb[RTA_SRC]) < plen)
2394                         goto errout;
2395
2396                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2397         }
2398
2399         if (tb[RTA_PREFSRC])
2400                 nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16);
2401
2402         if (tb[RTA_OIF])
2403                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2404
2405         if (tb[RTA_PRIORITY])
2406                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2407
2408         if (tb[RTA_METRICS]) {
2409                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2410                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2411         }
2412
2413         if (tb[RTA_TABLE])
2414                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2415
2416         if (tb[RTA_MULTIPATH]) {
2417                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2418                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2419         }
2420
2421         err = 0;
2422 errout:
2423         return err;
2424 }
2425
2426 static int ip6_route_multipath(struct fib6_config *cfg, int add)
2427 {
2428         struct fib6_config r_cfg;
2429         struct rtnexthop *rtnh;
2430         int remaining;
2431         int attrlen;
2432         int err = 0, last_err = 0;
2433
2434 beginning:
2435         rtnh = (struct rtnexthop *)cfg->fc_mp;
2436         remaining = cfg->fc_mp_len;
2437
2438         /* Parse a Multipath Entry */
2439         while (rtnh_ok(rtnh, remaining)) {
2440                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2441                 if (rtnh->rtnh_ifindex)
2442                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2443
2444                 attrlen = rtnh_attrlen(rtnh);
2445                 if (attrlen > 0) {
2446                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2447
2448                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2449                         if (nla) {
2450                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2451                                 r_cfg.fc_flags |= RTF_GATEWAY;
2452                         }
2453                 }
2454                 err = add ? ip6_route_add(&r_cfg) : ip6_route_del(&r_cfg);
2455                 if (err) {
2456                         last_err = err;
2457                         /* If we are trying to remove a route, do not stop the
2458                          * loop when ip6_route_del() fails (because next hop is
2459                          * already gone), we should try to remove all next hops.
2460                          */
2461                         if (add) {
2462                                 /* If add fails, we should try to delete all
2463                                  * next hops that have been already added.
2464                                  */
2465                                 add = 0;
2466                                 goto beginning;
2467                         }
2468                 }
2469                 /* Because each route is added like a single route we remove
2470                  * this flag after the first nexthop (if there is a collision,
2471                  * we have already fail to add the first nexthop:
2472                  * fib6_add_rt2node() has reject it).
2473                  */
2474                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~NLM_F_EXCL;
2475                 rtnh = rtnh_next(rtnh, &remaining);
2476         }
2477
2478         return last_err;
2479 }
2480
2481 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh)
2482 {
2483         struct fib6_config cfg;
2484         int err;
2485
2486         err = rtm_to_fib6_config(skb, nlh, &cfg);
2487         if (err < 0)
2488                 return err;
2489
2490         if (cfg.fc_mp)
2491                 return ip6_route_multipath(&cfg, 0);
2492         else
2493                 return ip6_route_del(&cfg);
2494 }
2495
2496 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh)
2497 {
2498         struct fib6_config cfg;
2499         int err;
2500
2501         err = rtm_to_fib6_config(skb, nlh, &cfg);
2502         if (err < 0)
2503                 return err;
2504
2505         if (cfg.fc_mp)
2506                 return ip6_route_multipath(&cfg, 1);
2507         else
2508                 return ip6_route_add(&cfg);
2509 }
2510
2511 static inline size_t rt6_nlmsg_size(void)
2512 {
2513         return NLMSG_ALIGN(sizeof(struct rtmsg))
2514                + nla_total_size(16) /* RTA_SRC */
2515                + nla_total_size(16) /* RTA_DST */
2516                + nla_total_size(16) /* RTA_GATEWAY */
2517                + nla_total_size(16) /* RTA_PREFSRC */
2518                + nla_total_size(4) /* RTA_TABLE */
2519                + nla_total_size(4) /* RTA_IIF */
2520                + nla_total_size(4) /* RTA_OIF */
2521                + nla_total_size(4) /* RTA_PRIORITY */
2522                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2523                + nla_total_size(sizeof(struct rta_cacheinfo));
2524 }
2525
2526 static int rt6_fill_node(struct net *net,
2527                          struct sk_buff *skb, struct rt6_info *rt,
2528                          struct in6_addr *dst, struct in6_addr *src,
2529                          int iif, int type, u32 portid, u32 seq,
2530                          int prefix, int nowait, unsigned int flags)
2531 {
2532         struct rtmsg *rtm;
2533         struct nlmsghdr *nlh;
2534         long expires;
2535         u32 table;
2536
2537         if (prefix) {   /* user wants prefix routes only */
2538                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2539                         /* success since this is not a prefix route */
2540                         return 1;
2541                 }
2542         }
2543
2544         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
2545         if (!nlh)
2546                 return -EMSGSIZE;
2547
2548         rtm = nlmsg_data(nlh);
2549         rtm->rtm_family = AF_INET6;
2550         rtm->rtm_dst_len = rt->rt6i_dst.plen;
2551         rtm->rtm_src_len = rt->rt6i_src.plen;
2552         rtm->rtm_tos = 0;
2553         if (rt->rt6i_table)
2554                 table = rt->rt6i_table->tb6_id;
2555         else
2556                 table = RT6_TABLE_UNSPEC;
2557         rtm->rtm_table = table;
2558         if (nla_put_u32(skb, RTA_TABLE, table))
2559                 goto nla_put_failure;
2560         if (rt->rt6i_flags & RTF_REJECT) {
2561                 switch (rt->dst.error) {
2562                 case -EINVAL:
2563                         rtm->rtm_type = RTN_BLACKHOLE;
2564                         break;
2565                 case -EACCES:
2566                         rtm->rtm_type = RTN_PROHIBIT;
2567                         break;
2568                 case -EAGAIN:
2569                         rtm->rtm_type = RTN_THROW;
2570                         break;
2571                 default:
2572                         rtm->rtm_type = RTN_UNREACHABLE;
2573                         break;
2574                 }
2575         }
2576         else if (rt->rt6i_flags & RTF_LOCAL)
2577                 rtm->rtm_type = RTN_LOCAL;
2578         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
2579                 rtm->rtm_type = RTN_LOCAL;
2580         else
2581                 rtm->rtm_type = RTN_UNICAST;
2582         rtm->rtm_flags = 0;
2583         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2584         rtm->rtm_protocol = rt->rt6i_protocol;
2585         if (rt->rt6i_flags & RTF_DYNAMIC)
2586                 rtm->rtm_protocol = RTPROT_REDIRECT;
2587         else if (rt->rt6i_flags & RTF_ADDRCONF) {
2588                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
2589                         rtm->rtm_protocol = RTPROT_RA;
2590                 else
2591                         rtm->rtm_protocol = RTPROT_KERNEL;
2592         }
2593
2594         if (rt->rt6i_flags & RTF_CACHE)
2595                 rtm->rtm_flags |= RTM_F_CLONED;
2596
2597         if (dst) {
2598                 if (nla_put(skb, RTA_DST, 16, dst))
2599                         goto nla_put_failure;
2600                 rtm->rtm_dst_len = 128;
2601         } else if (rtm->rtm_dst_len)
2602                 if (nla_put(skb, RTA_DST, 16, &rt->rt6i_dst.addr))
2603                         goto nla_put_failure;
2604 #ifdef CONFIG_IPV6_SUBTREES
2605         if (src) {
2606                 if (nla_put(skb, RTA_SRC, 16, src))
2607                         goto nla_put_failure;
2608                 rtm->rtm_src_len = 128;
2609         } else if (rtm->rtm_src_len &&
2610                    nla_put(skb, RTA_SRC, 16, &rt->rt6i_src.addr))
2611                 goto nla_put_failure;
2612 #endif
2613         if (iif) {
2614 #ifdef CONFIG_IPV6_MROUTE
2615                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2616                         int err = ip6mr_get_route(net, skb, rtm, nowait);
2617                         if (err <= 0) {
2618                                 if (!nowait) {
2619                                         if (err == 0)
2620                                                 return 0;
2621                                         goto nla_put_failure;
2622                                 } else {
2623                                         if (err == -EMSGSIZE)
2624                                                 goto nla_put_failure;
2625                                 }
2626                         }
2627                 } else
2628 #endif
2629                         if (nla_put_u32(skb, RTA_IIF, iif))
2630                                 goto nla_put_failure;
2631         } else if (dst) {
2632                 struct in6_addr saddr_buf;
2633                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
2634                     nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
2635                         goto nla_put_failure;
2636         }
2637
2638         if (rt->rt6i_prefsrc.plen) {
2639                 struct in6_addr saddr_buf;
2640                 saddr_buf = rt->rt6i_prefsrc.addr;
2641                 if (nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
2642                         goto nla_put_failure;
2643         }
2644
2645         if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2646                 goto nla_put_failure;
2647
2648         if (rt->rt6i_flags & RTF_GATEWAY) {
2649                 if (nla_put(skb, RTA_GATEWAY, 16, &rt->rt6i_gateway) < 0)
2650                         goto nla_put_failure;
2651         }
2652
2653         if (rt->dst.dev &&
2654             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2655                 goto nla_put_failure;
2656         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
2657                 goto nla_put_failure;
2658
2659         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
2660
2661         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
2662                 goto nla_put_failure;
2663
2664         return nlmsg_end(skb, nlh);
2665
2666 nla_put_failure:
2667         nlmsg_cancel(skb, nlh);
2668         return -EMSGSIZE;
2669 }
2670
2671 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2672 {
2673         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2674         int prefix;
2675
2676         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2677                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2678                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2679         } else
2680                 prefix = 0;
2681
2682         return rt6_fill_node(arg->net,
2683                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2684                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
2685                      prefix, 0, NLM_F_MULTI);
2686 }
2687
2688 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh)
2689 {
2690         struct net *net = sock_net(in_skb->sk);
2691         struct nlattr *tb[RTA_MAX+1];
2692         struct rt6_info *rt;
2693         struct sk_buff *skb;
2694         struct rtmsg *rtm;
2695         struct flowi6 fl6;
2696         int err, iif = 0, oif = 0;
2697
2698         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2699         if (err < 0)
2700                 goto errout;
2701
2702         err = -EINVAL;
2703         memset(&fl6, 0, sizeof(fl6));
2704
2705         if (tb[RTA_SRC]) {
2706                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2707                         goto errout;
2708
2709                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
2710         }
2711
2712         if (tb[RTA_DST]) {
2713                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2714                         goto errout;
2715
2716                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
2717         }
2718
2719         if (tb[RTA_IIF])
2720                 iif = nla_get_u32(tb[RTA_IIF]);
2721
2722         if (tb[RTA_OIF])
2723                 oif = nla_get_u32(tb[RTA_OIF]);
2724
2725         if (iif) {
2726                 struct net_device *dev;
2727                 int flags = 0;
2728
2729                 dev = __dev_get_by_index(net, iif);
2730                 if (!dev) {
2731                         err = -ENODEV;
2732                         goto errout;
2733                 }
2734
2735                 fl6.flowi6_iif = iif;
2736
2737                 if (!ipv6_addr_any(&fl6.saddr))
2738                         flags |= RT6_LOOKUP_F_HAS_SADDR;
2739
2740                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
2741                                                                flags);
2742         } else {
2743                 fl6.flowi6_oif = oif;
2744
2745                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
2746         }
2747
2748         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2749         if (!skb) {
2750                 ip6_rt_put(rt);
2751                 err = -ENOBUFS;
2752                 goto errout;
2753         }
2754
2755         /* Reserve room for dummy headers, this skb can pass
2756            through good chunk of routing engine.
2757          */
2758         skb_reset_mac_header(skb);
2759         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2760
2761         skb_dst_set(skb, &rt->dst);
2762
2763         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
2764                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
2765                             nlh->nlmsg_seq, 0, 0, 0);
2766         if (err < 0) {
2767                 kfree_skb(skb);
2768                 goto errout;
2769         }
2770
2771         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2772 errout:
2773         return err;
2774 }
2775
2776 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2777 {
2778         struct sk_buff *skb;
2779         struct net *net = info->nl_net;
2780         u32 seq;
2781         int err;
2782
2783         err = -ENOBUFS;
2784         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
2785
2786         skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2787         if (!skb)
2788                 goto errout;
2789
2790         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2791                                 event, info->portid, seq, 0, 0, 0);
2792         if (err < 0) {
2793                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2794                 WARN_ON(err == -EMSGSIZE);
2795                 kfree_skb(skb);
2796                 goto errout;
2797         }
2798         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
2799                     info->nlh, gfp_any());
2800         return;
2801 errout:
2802         if (err < 0)
2803                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2804 }
2805
2806 static int ip6_route_dev_notify(struct notifier_block *this,
2807                                 unsigned long event, void *ptr)
2808 {
2809         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2810         struct net *net = dev_net(dev);
2811
2812         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2813                 net->ipv6.ip6_null_entry->dst.dev = dev;
2814                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2815 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2816                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2817                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2818                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2819                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2820 #endif
2821         }
2822
2823         return NOTIFY_OK;
2824 }
2825
2826 /*
2827  *      /proc
2828  */
2829
2830 #ifdef CONFIG_PROC_FS
2831
2832 static const struct file_operations ipv6_route_proc_fops = {
2833         .owner          = THIS_MODULE,
2834         .open           = ipv6_route_open,
2835         .read           = seq_read,
2836         .llseek         = seq_lseek,
2837         .release        = seq_release_net,
2838 };
2839
2840 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2841 {
2842         struct net *net = (struct net *)seq->private;
2843         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2844                    net->ipv6.rt6_stats->fib_nodes,
2845                    net->ipv6.rt6_stats->fib_route_nodes,
2846                    net->ipv6.rt6_stats->fib_rt_alloc,
2847                    net->ipv6.rt6_stats->fib_rt_entries,
2848                    net->ipv6.rt6_stats->fib_rt_cache,
2849                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2850                    net->ipv6.rt6_stats->fib_discarded_routes);
2851
2852         return 0;
2853 }
2854
2855 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2856 {
2857         return single_open_net(inode, file, rt6_stats_seq_show);
2858 }
2859
2860 static const struct file_operations rt6_stats_seq_fops = {
2861         .owner   = THIS_MODULE,
2862         .open    = rt6_stats_seq_open,
2863         .read    = seq_read,
2864         .llseek  = seq_lseek,
2865         .release = single_release_net,
2866 };
2867 #endif  /* CONFIG_PROC_FS */
2868
2869 #ifdef CONFIG_SYSCTL
2870
2871 static
2872 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
2873                               void __user *buffer, size_t *lenp, loff_t *ppos)
2874 {
2875         struct net *net;
2876         int delay;
2877         if (!write)
2878                 return -EINVAL;
2879
2880         net = (struct net *)ctl->extra1;
2881         delay = net->ipv6.sysctl.flush_delay;
2882         proc_dointvec(ctl, write, buffer, lenp, ppos);
2883         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
2884         return 0;
2885 }
2886
2887 struct ctl_table ipv6_route_table_template[] = {
2888         {
2889                 .procname       =       "flush",
2890                 .data           =       &init_net.ipv6.sysctl.flush_delay,
2891                 .maxlen         =       sizeof(int),
2892                 .mode           =       0200,
2893                 .proc_handler   =       ipv6_sysctl_rtcache_flush
2894         },
2895         {
2896                 .procname       =       "gc_thresh",
2897                 .data           =       &ip6_dst_ops_template.gc_thresh,
2898                 .maxlen         =       sizeof(int),
2899                 .mode           =       0644,
2900                 .proc_handler   =       proc_dointvec,
2901         },
2902         {
2903                 .procname       =       "max_size",
2904                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
2905                 .maxlen         =       sizeof(int),
2906                 .mode           =       0644,
2907                 .proc_handler   =       proc_dointvec,
2908         },
2909         {
2910                 .procname       =       "gc_min_interval",
2911                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2912                 .maxlen         =       sizeof(int),
2913                 .mode           =       0644,
2914                 .proc_handler   =       proc_dointvec_jiffies,
2915         },
2916         {
2917                 .procname       =       "gc_timeout",
2918                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2919                 .maxlen         =       sizeof(int),
2920                 .mode           =       0644,
2921                 .proc_handler   =       proc_dointvec_jiffies,
2922         },
2923         {
2924                 .procname       =       "gc_interval",
2925                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2926                 .maxlen         =       sizeof(int),
2927                 .mode           =       0644,
2928                 .proc_handler   =       proc_dointvec_jiffies,
2929         },
2930         {
2931                 .procname       =       "gc_elasticity",
2932                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2933                 .maxlen         =       sizeof(int),
2934                 .mode           =       0644,
2935                 .proc_handler   =       proc_dointvec,
2936         },
2937         {
2938                 .procname       =       "mtu_expires",
2939                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2940                 .maxlen         =       sizeof(int),
2941                 .mode           =       0644,
2942                 .proc_handler   =       proc_dointvec_jiffies,
2943         },
2944         {
2945                 .procname       =       "min_adv_mss",
2946                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2947                 .maxlen         =       sizeof(int),
2948                 .mode           =       0644,
2949                 .proc_handler   =       proc_dointvec,
2950         },
2951         {
2952                 .procname       =       "gc_min_interval_ms",
2953                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2954                 .maxlen         =       sizeof(int),
2955                 .mode           =       0644,
2956                 .proc_handler   =       proc_dointvec_ms_jiffies,
2957         },
2958         { }
2959 };
2960
2961 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2962 {
2963         struct ctl_table *table;
2964
2965         table = kmemdup(ipv6_route_table_template,
2966                         sizeof(ipv6_route_table_template),
2967                         GFP_KERNEL);
2968
2969         if (table) {
2970                 table[0].data = &net->ipv6.sysctl.flush_delay;
2971                 table[0].extra1 = net;
2972                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2973                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2974                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2975                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2976                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2977                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2978                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2979                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2980                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2981
2982                 /* Don't export sysctls to unprivileged users */
2983                 if (net->user_ns != &init_user_ns)
2984                         table[0].procname = NULL;
2985         }
2986
2987         return table;
2988 }
2989 #endif
2990
2991 static int __net_init ip6_route_net_init(struct net *net)
2992 {
2993         int ret = -ENOMEM;
2994
2995         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
2996                sizeof(net->ipv6.ip6_dst_ops));
2997
2998         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
2999                 goto out_ip6_dst_ops;
3000
3001         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3002                                            sizeof(*net->ipv6.ip6_null_entry),
3003                                            GFP_KERNEL);
3004         if (!net->ipv6.ip6_null_entry)
3005                 goto out_ip6_dst_entries;
3006         net->ipv6.ip6_null_entry->dst.path =
3007                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3008         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3009         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3010                          ip6_template_metrics, true);
3011
3012 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3013         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3014                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3015                                                GFP_KERNEL);
3016         if (!net->ipv6.ip6_prohibit_entry)
3017                 goto out_ip6_null_entry;
3018         net->ipv6.ip6_prohibit_entry->dst.path =
3019                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3020         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3021         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3022                          ip6_template_metrics, true);
3023
3024         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3025                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3026                                                GFP_KERNEL);
3027         if (!net->ipv6.ip6_blk_hole_entry)
3028                 goto out_ip6_prohibit_entry;
3029         net->ipv6.ip6_blk_hole_entry->dst.path =
3030                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3031         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3032         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3033                          ip6_template_metrics, true);
3034 #endif
3035
3036         net->ipv6.sysctl.flush_delay = 0;
3037         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3038         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3039         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3040         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3041         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3042         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3043         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3044
3045         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3046
3047         ret = 0;
3048 out:
3049         return ret;
3050
3051 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3052 out_ip6_prohibit_entry:
3053         kfree(net->ipv6.ip6_prohibit_entry);
3054 out_ip6_null_entry:
3055         kfree(net->ipv6.ip6_null_entry);
3056 #endif
3057 out_ip6_dst_entries:
3058         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3059 out_ip6_dst_ops:
3060         goto out;
3061 }
3062
3063 static void __net_exit ip6_route_net_exit(struct net *net)
3064 {
3065         kfree(net->ipv6.ip6_null_entry);
3066 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3067         kfree(net->ipv6.ip6_prohibit_entry);
3068         kfree(net->ipv6.ip6_blk_hole_entry);
3069 #endif
3070         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3071 }
3072
3073 static int __net_init ip6_route_net_init_late(struct net *net)
3074 {
3075 #ifdef CONFIG_PROC_FS
3076         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3077         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3078 #endif
3079         return 0;
3080 }
3081
3082 static void __net_exit ip6_route_net_exit_late(struct net *net)
3083 {
3084 #ifdef CONFIG_PROC_FS
3085         remove_proc_entry("ipv6_route", net->proc_net);
3086         remove_proc_entry("rt6_stats", net->proc_net);
3087 #endif
3088 }
3089
3090 static struct pernet_operations ip6_route_net_ops = {
3091         .init = ip6_route_net_init,
3092         .exit = ip6_route_net_exit,
3093 };
3094
3095 static int __net_init ipv6_inetpeer_init(struct net *net)
3096 {
3097         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3098
3099         if (!bp)
3100                 return -ENOMEM;
3101         inet_peer_base_init(bp);
3102         net->ipv6.peers = bp;
3103         return 0;
3104 }
3105
3106 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3107 {
3108         struct inet_peer_base *bp = net->ipv6.peers;
3109
3110         net->ipv6.peers = NULL;
3111         inetpeer_invalidate_tree(bp);
3112         kfree(bp);
3113 }
3114
3115 static struct pernet_operations ipv6_inetpeer_ops = {
3116         .init   =       ipv6_inetpeer_init,
3117         .exit   =       ipv6_inetpeer_exit,
3118 };
3119
3120 static struct pernet_operations ip6_route_net_late_ops = {
3121         .init = ip6_route_net_init_late,
3122         .exit = ip6_route_net_exit_late,
3123 };
3124
3125 static struct notifier_block ip6_route_dev_notifier = {
3126         .notifier_call = ip6_route_dev_notify,
3127         .priority = 0,
3128 };
3129
3130 int __init ip6_route_init(void)
3131 {
3132         int ret;
3133
3134         ret = -ENOMEM;
3135         ip6_dst_ops_template.kmem_cachep =
3136                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3137                                   SLAB_HWCACHE_ALIGN, NULL);
3138         if (!ip6_dst_ops_template.kmem_cachep)
3139                 goto out;
3140
3141         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3142         if (ret)
3143                 goto out_kmem_cache;
3144
3145         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3146         if (ret)
3147                 goto out_dst_entries;
3148
3149         ret = register_pernet_subsys(&ip6_route_net_ops);
3150         if (ret)
3151                 goto out_register_inetpeer;
3152
3153         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3154
3155         /* Registering of the loopback is done before this portion of code,
3156          * the loopback reference in rt6_info will not be taken, do it
3157          * manually for init_net */
3158         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3159         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3160   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3161         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3162         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3163         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3164         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3165   #endif
3166         ret = fib6_init();
3167         if (ret)
3168                 goto out_register_subsys;
3169
3170         ret = xfrm6_init();
3171         if (ret)
3172                 goto out_fib6_init;
3173
3174         ret = fib6_rules_init();
3175         if (ret)
3176                 goto xfrm6_init;
3177
3178         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3179         if (ret)
3180                 goto fib6_rules_init;
3181
3182         ret = -ENOBUFS;
3183         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3184             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3185             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3186                 goto out_register_late_subsys;
3187
3188         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3189         if (ret)
3190                 goto out_register_late_subsys;
3191
3192 out:
3193         return ret;
3194
3195 out_register_late_subsys:
3196         unregister_pernet_subsys(&ip6_route_net_late_ops);
3197 fib6_rules_init:
3198         fib6_rules_cleanup();
3199 xfrm6_init:
3200         xfrm6_fini();
3201 out_fib6_init:
3202         fib6_gc_cleanup();
3203 out_register_subsys:
3204         unregister_pernet_subsys(&ip6_route_net_ops);
3205 out_register_inetpeer:
3206         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3207 out_dst_entries:
3208         dst_entries_destroy(&ip6_dst_blackhole_ops);
3209 out_kmem_cache:
3210         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3211         goto out;
3212 }
3213
3214 void ip6_route_cleanup(void)
3215 {
3216         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3217         unregister_pernet_subsys(&ip6_route_net_late_ops);
3218         fib6_rules_cleanup();
3219         xfrm6_fini();
3220         fib6_gc_cleanup();
3221         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3222         unregister_pernet_subsys(&ip6_route_net_ops);
3223         dst_entries_destroy(&ip6_dst_blackhole_ops);
3224         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3225 }