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1 /*
2  *      Linux INET6 implementation
3  *      FIB front-end.
4  *
5  *      Authors:
6  *      Pedro Roque             <roque@di.fc.ul.pt>
7  *
8  *      This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  */
13
14 /*      Changes:
15  *
16  *      YOSHIFUJI Hideaki @USAGI
17  *              reworked default router selection.
18  *              - respect outgoing interface
19  *              - select from (probably) reachable routers (i.e.
20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
21  *              - always select the same router if it is (probably)
22  *              reachable.  otherwise, round-robin the list.
23  *      Ville Nuorvala
24  *              Fixed routing subtrees.
25  */
26
27 #define pr_fmt(fmt) "IPv6: " fmt
28
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/export.h>
32 #include <linux/types.h>
33 #include <linux/times.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <linux/net.h>
37 #include <linux/route.h>
38 #include <linux/netdevice.h>
39 #include <linux/in6.h>
40 #include <linux/mroute6.h>
41 #include <linux/init.h>
42 #include <linux/if_arp.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/nsproxy.h>
46 #include <linux/slab.h>
47 #include <net/net_namespace.h>
48 #include <net/snmp.h>
49 #include <net/ipv6.h>
50 #include <net/ip6_fib.h>
51 #include <net/ip6_route.h>
52 #include <net/ndisc.h>
53 #include <net/addrconf.h>
54 #include <net/tcp.h>
55 #include <linux/rtnetlink.h>
56 #include <net/dst.h>
57 #include <net/dst_metadata.h>
58 #include <net/xfrm.h>
59 #include <net/netevent.h>
60 #include <net/netlink.h>
61 #include <net/nexthop.h>
62 #include <net/lwtunnel.h>
63 #include <net/ip_tunnels.h>
64
65 #include <asm/uaccess.h>
66
67 #ifdef CONFIG_SYSCTL
68 #include <linux/sysctl.h>
69 #endif
70
71 enum rt6_nud_state {
72         RT6_NUD_FAIL_HARD = -3,
73         RT6_NUD_FAIL_PROBE = -2,
74         RT6_NUD_FAIL_DO_RR = -1,
75         RT6_NUD_SUCCEED = 1
76 };
77
78 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
79 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
80 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
81 static unsigned int      ip6_mtu(const struct dst_entry *dst);
82 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
83 static void             ip6_dst_destroy(struct dst_entry *);
84 static void             ip6_dst_ifdown(struct dst_entry *,
85                                        struct net_device *dev, int how);
86 static int               ip6_dst_gc(struct dst_ops *ops);
87
88 static int              ip6_pkt_discard(struct sk_buff *skb);
89 static int              ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb);
90 static int              ip6_pkt_prohibit(struct sk_buff *skb);
91 static int              ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb);
92 static void             ip6_link_failure(struct sk_buff *skb);
93 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
94                                            struct sk_buff *skb, u32 mtu);
95 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
96                                         struct sk_buff *skb);
97 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
98 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
99
100 #ifdef CONFIG_IPV6_ROUTE_INFO
101 static struct rt6_info *rt6_add_route_info(struct net *net,
102                                            const struct in6_addr *prefix, int prefixlen,
103                                            const struct in6_addr *gwaddr, int ifindex,
104                                            unsigned int pref);
105 static struct rt6_info *rt6_get_route_info(struct net *net,
106                                            const struct in6_addr *prefix, int prefixlen,
107                                            const struct in6_addr *gwaddr, int ifindex);
108 #endif
109
110 struct uncached_list {
111         spinlock_t              lock;
112         struct list_head        head;
113 };
114
115 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
116
117 static void rt6_uncached_list_add(struct rt6_info *rt)
118 {
119         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
120
121         rt->dst.flags |= DST_NOCACHE;
122         rt->rt6i_uncached_list = ul;
123
124         spin_lock_bh(&ul->lock);
125         list_add_tail(&rt->rt6i_uncached, &ul->head);
126         spin_unlock_bh(&ul->lock);
127 }
128
129 static void rt6_uncached_list_del(struct rt6_info *rt)
130 {
131         if (!list_empty(&rt->rt6i_uncached)) {
132                 struct uncached_list *ul = rt->rt6i_uncached_list;
133
134                 spin_lock_bh(&ul->lock);
135                 list_del(&rt->rt6i_uncached);
136                 spin_unlock_bh(&ul->lock);
137         }
138 }
139
140 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
141 {
142         struct net_device *loopback_dev = net->loopback_dev;
143         int cpu;
144
145         if (dev == loopback_dev)
146                 return;
147
148         for_each_possible_cpu(cpu) {
149                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
150                 struct rt6_info *rt;
151
152                 spin_lock_bh(&ul->lock);
153                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
154                         struct inet6_dev *rt_idev = rt->rt6i_idev;
155                         struct net_device *rt_dev = rt->dst.dev;
156
157                         if (rt_idev->dev == dev) {
158                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
159                                 in6_dev_put(rt_idev);
160                         }
161
162                         if (rt_dev == dev) {
163                                 rt->dst.dev = loopback_dev;
164                                 dev_hold(rt->dst.dev);
165                                 dev_put(rt_dev);
166                         }
167                 }
168                 spin_unlock_bh(&ul->lock);
169         }
170 }
171
172 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
173 {
174         return dst_metrics_write_ptr(rt->dst.from);
175 }
176
177 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
178 {
179         struct rt6_info *rt = (struct rt6_info *)dst;
180
181         if (rt->rt6i_flags & RTF_PCPU)
182                 return rt6_pcpu_cow_metrics(rt);
183         else if (rt->rt6i_flags & RTF_CACHE)
184                 return NULL;
185         else
186                 return dst_cow_metrics_generic(dst, old);
187 }
188
189 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
190                                              struct sk_buff *skb,
191                                              const void *daddr)
192 {
193         struct in6_addr *p = &rt->rt6i_gateway;
194
195         if (!ipv6_addr_any(p))
196                 return (const void *) p;
197         else if (skb)
198                 return &ipv6_hdr(skb)->daddr;
199         return daddr;
200 }
201
202 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
203                                           struct sk_buff *skb,
204                                           const void *daddr)
205 {
206         struct rt6_info *rt = (struct rt6_info *) dst;
207         struct neighbour *n;
208
209         daddr = choose_neigh_daddr(rt, skb, daddr);
210         n = __ipv6_neigh_lookup(dst->dev, daddr);
211         if (n)
212                 return n;
213         return neigh_create(&nd_tbl, daddr, dst->dev);
214 }
215
216 static struct dst_ops ip6_dst_ops_template = {
217         .family                 =       AF_INET6,
218         .gc                     =       ip6_dst_gc,
219         .gc_thresh              =       1024,
220         .check                  =       ip6_dst_check,
221         .default_advmss         =       ip6_default_advmss,
222         .mtu                    =       ip6_mtu,
223         .cow_metrics            =       ipv6_cow_metrics,
224         .destroy                =       ip6_dst_destroy,
225         .ifdown                 =       ip6_dst_ifdown,
226         .negative_advice        =       ip6_negative_advice,
227         .link_failure           =       ip6_link_failure,
228         .update_pmtu            =       ip6_rt_update_pmtu,
229         .redirect               =       rt6_do_redirect,
230         .local_out              =       __ip6_local_out,
231         .neigh_lookup           =       ip6_neigh_lookup,
232 };
233
234 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
235 {
236         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
237
238         return mtu ? : dst->dev->mtu;
239 }
240
241 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
242                                          struct sk_buff *skb, u32 mtu)
243 {
244 }
245
246 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
247                                       struct sk_buff *skb)
248 {
249 }
250
251 static struct dst_ops ip6_dst_blackhole_ops = {
252         .family                 =       AF_INET6,
253         .destroy                =       ip6_dst_destroy,
254         .check                  =       ip6_dst_check,
255         .mtu                    =       ip6_blackhole_mtu,
256         .default_advmss         =       ip6_default_advmss,
257         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
258         .redirect               =       ip6_rt_blackhole_redirect,
259         .cow_metrics            =       dst_cow_metrics_generic,
260         .neigh_lookup           =       ip6_neigh_lookup,
261 };
262
263 static const u32 ip6_template_metrics[RTAX_MAX] = {
264         [RTAX_HOPLIMIT - 1] = 0,
265 };
266
267 static const struct rt6_info ip6_null_entry_template = {
268         .dst = {
269                 .__refcnt       = ATOMIC_INIT(1),
270                 .__use          = 1,
271                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
272                 .error          = -ENETUNREACH,
273                 .input          = ip6_pkt_discard,
274                 .output         = ip6_pkt_discard_out,
275         },
276         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
277         .rt6i_protocol  = RTPROT_KERNEL,
278         .rt6i_metric    = ~(u32) 0,
279         .rt6i_ref       = ATOMIC_INIT(1),
280 };
281
282 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
283
284 static const struct rt6_info ip6_prohibit_entry_template = {
285         .dst = {
286                 .__refcnt       = ATOMIC_INIT(1),
287                 .__use          = 1,
288                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
289                 .error          = -EACCES,
290                 .input          = ip6_pkt_prohibit,
291                 .output         = ip6_pkt_prohibit_out,
292         },
293         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
294         .rt6i_protocol  = RTPROT_KERNEL,
295         .rt6i_metric    = ~(u32) 0,
296         .rt6i_ref       = ATOMIC_INIT(1),
297 };
298
299 static const struct rt6_info ip6_blk_hole_entry_template = {
300         .dst = {
301                 .__refcnt       = ATOMIC_INIT(1),
302                 .__use          = 1,
303                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
304                 .error          = -EINVAL,
305                 .input          = dst_discard,
306                 .output         = dst_discard_sk,
307         },
308         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
309         .rt6i_protocol  = RTPROT_KERNEL,
310         .rt6i_metric    = ~(u32) 0,
311         .rt6i_ref       = ATOMIC_INIT(1),
312 };
313
314 #endif
315
316 static void rt6_info_init(struct rt6_info *rt)
317 {
318         struct dst_entry *dst = &rt->dst;
319
320         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
321         INIT_LIST_HEAD(&rt->rt6i_siblings);
322         INIT_LIST_HEAD(&rt->rt6i_uncached);
323 }
324
325 /* allocate dst with ip6_dst_ops */
326 static struct rt6_info *__ip6_dst_alloc(struct net *net,
327                                         struct net_device *dev,
328                                         int flags)
329 {
330         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
331                                         0, DST_OBSOLETE_FORCE_CHK, flags);
332
333         if (rt)
334                 rt6_info_init(rt);
335
336         return rt;
337 }
338
339 static struct rt6_info *ip6_dst_alloc(struct net *net,
340                                       struct net_device *dev,
341                                       int flags)
342 {
343         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
344
345         if (rt) {
346                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
347                 if (rt->rt6i_pcpu) {
348                         int cpu;
349
350                         for_each_possible_cpu(cpu) {
351                                 struct rt6_info **p;
352
353                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
354                                 /* no one shares rt */
355                                 *p =  NULL;
356                         }
357                 } else {
358                         dst_destroy((struct dst_entry *)rt);
359                         return NULL;
360                 }
361         }
362
363         return rt;
364 }
365
366 static void ip6_dst_destroy(struct dst_entry *dst)
367 {
368         struct rt6_info *rt = (struct rt6_info *)dst;
369         struct dst_entry *from = dst->from;
370         struct inet6_dev *idev;
371
372         dst_destroy_metrics_generic(dst);
373         free_percpu(rt->rt6i_pcpu);
374         rt6_uncached_list_del(rt);
375
376         idev = rt->rt6i_idev;
377         if (idev) {
378                 rt->rt6i_idev = NULL;
379                 in6_dev_put(idev);
380         }
381
382         dst->from = NULL;
383         dst_release(from);
384 }
385
386 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
387                            int how)
388 {
389         struct rt6_info *rt = (struct rt6_info *)dst;
390         struct inet6_dev *idev = rt->rt6i_idev;
391         struct net_device *loopback_dev =
392                 dev_net(dev)->loopback_dev;
393
394         if (dev != loopback_dev) {
395                 if (idev && idev->dev == dev) {
396                         struct inet6_dev *loopback_idev =
397                                 in6_dev_get(loopback_dev);
398                         if (loopback_idev) {
399                                 rt->rt6i_idev = loopback_idev;
400                                 in6_dev_put(idev);
401                         }
402                 }
403         }
404 }
405
406 static bool rt6_check_expired(const struct rt6_info *rt)
407 {
408         if (rt->rt6i_flags & RTF_EXPIRES) {
409                 if (time_after(jiffies, rt->dst.expires))
410                         return true;
411         } else if (rt->dst.from) {
412                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
413         }
414         return false;
415 }
416
417 /* Multipath route selection:
418  *   Hash based function using packet header and flowlabel.
419  * Adapted from fib_info_hashfn()
420  */
421 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
422                                const struct flowi6 *fl6)
423 {
424         unsigned int val = fl6->flowi6_proto;
425
426         val ^= ipv6_addr_hash(&fl6->daddr);
427         val ^= ipv6_addr_hash(&fl6->saddr);
428
429         /* Work only if this not encapsulated */
430         switch (fl6->flowi6_proto) {
431         case IPPROTO_UDP:
432         case IPPROTO_TCP:
433         case IPPROTO_SCTP:
434                 val ^= (__force u16)fl6->fl6_sport;
435                 val ^= (__force u16)fl6->fl6_dport;
436                 break;
437
438         case IPPROTO_ICMPV6:
439                 val ^= (__force u16)fl6->fl6_icmp_type;
440                 val ^= (__force u16)fl6->fl6_icmp_code;
441                 break;
442         }
443         /* RFC6438 recommands to use flowlabel */
444         val ^= (__force u32)fl6->flowlabel;
445
446         /* Perhaps, we need to tune, this function? */
447         val = val ^ (val >> 7) ^ (val >> 12);
448         return val % candidate_count;
449 }
450
451 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
452                                              struct flowi6 *fl6, int oif,
453                                              int strict)
454 {
455         struct rt6_info *sibling, *next_sibling;
456         int route_choosen;
457
458         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
459         /* Don't change the route, if route_choosen == 0
460          * (siblings does not include ourself)
461          */
462         if (route_choosen)
463                 list_for_each_entry_safe(sibling, next_sibling,
464                                 &match->rt6i_siblings, rt6i_siblings) {
465                         route_choosen--;
466                         if (route_choosen == 0) {
467                                 if (rt6_score_route(sibling, oif, strict) < 0)
468                                         break;
469                                 match = sibling;
470                                 break;
471                         }
472                 }
473         return match;
474 }
475
476 /*
477  *      Route lookup. Any table->tb6_lock is implied.
478  */
479
480 static inline struct rt6_info *rt6_device_match(struct net *net,
481                                                     struct rt6_info *rt,
482                                                     const struct in6_addr *saddr,
483                                                     int oif,
484                                                     int flags)
485 {
486         struct rt6_info *local = NULL;
487         struct rt6_info *sprt;
488
489         if (!oif && ipv6_addr_any(saddr))
490                 goto out;
491
492         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
493                 struct net_device *dev = sprt->dst.dev;
494
495                 if (oif) {
496                         if (dev->ifindex == oif)
497                                 return sprt;
498                         if (dev->flags & IFF_LOOPBACK) {
499                                 if (!sprt->rt6i_idev ||
500                                     sprt->rt6i_idev->dev->ifindex != oif) {
501                                         if (flags & RT6_LOOKUP_F_IFACE && oif)
502                                                 continue;
503                                         if (local && (!oif ||
504                                                       local->rt6i_idev->dev->ifindex == oif))
505                                                 continue;
506                                 }
507                                 local = sprt;
508                         }
509                 } else {
510                         if (ipv6_chk_addr(net, saddr, dev,
511                                           flags & RT6_LOOKUP_F_IFACE))
512                                 return sprt;
513                 }
514         }
515
516         if (oif) {
517                 if (local)
518                         return local;
519
520                 if (flags & RT6_LOOKUP_F_IFACE)
521                         return net->ipv6.ip6_null_entry;
522         }
523 out:
524         return rt;
525 }
526
527 #ifdef CONFIG_IPV6_ROUTER_PREF
528 struct __rt6_probe_work {
529         struct work_struct work;
530         struct in6_addr target;
531         struct net_device *dev;
532 };
533
534 static void rt6_probe_deferred(struct work_struct *w)
535 {
536         struct in6_addr mcaddr;
537         struct __rt6_probe_work *work =
538                 container_of(w, struct __rt6_probe_work, work);
539
540         addrconf_addr_solict_mult(&work->target, &mcaddr);
541         ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL, NULL);
542         dev_put(work->dev);
543         kfree(work);
544 }
545
546 static void rt6_probe(struct rt6_info *rt)
547 {
548         struct __rt6_probe_work *work;
549         struct neighbour *neigh;
550         /*
551          * Okay, this does not seem to be appropriate
552          * for now, however, we need to check if it
553          * is really so; aka Router Reachability Probing.
554          *
555          * Router Reachability Probe MUST be rate-limited
556          * to no more than one per minute.
557          */
558         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
559                 return;
560         rcu_read_lock_bh();
561         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
562         if (neigh) {
563                 if (neigh->nud_state & NUD_VALID)
564                         goto out;
565
566                 work = NULL;
567                 write_lock(&neigh->lock);
568                 if (!(neigh->nud_state & NUD_VALID) &&
569                     time_after(jiffies,
570                                neigh->updated +
571                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
572                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
573                         if (work)
574                                 __neigh_set_probe_once(neigh);
575                 }
576                 write_unlock(&neigh->lock);
577         } else {
578                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
579         }
580
581         if (work) {
582                 INIT_WORK(&work->work, rt6_probe_deferred);
583                 work->target = rt->rt6i_gateway;
584                 dev_hold(rt->dst.dev);
585                 work->dev = rt->dst.dev;
586                 schedule_work(&work->work);
587         }
588
589 out:
590         rcu_read_unlock_bh();
591 }
592 #else
593 static inline void rt6_probe(struct rt6_info *rt)
594 {
595 }
596 #endif
597
598 /*
599  * Default Router Selection (RFC 2461 6.3.6)
600  */
601 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
602 {
603         struct net_device *dev = rt->dst.dev;
604         if (!oif || dev->ifindex == oif)
605                 return 2;
606         if ((dev->flags & IFF_LOOPBACK) &&
607             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
608                 return 1;
609         return 0;
610 }
611
612 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
613 {
614         struct neighbour *neigh;
615         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
616
617         if (rt->rt6i_flags & RTF_NONEXTHOP ||
618             !(rt->rt6i_flags & RTF_GATEWAY))
619                 return RT6_NUD_SUCCEED;
620
621         rcu_read_lock_bh();
622         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
623         if (neigh) {
624                 read_lock(&neigh->lock);
625                 if (neigh->nud_state & NUD_VALID)
626                         ret = RT6_NUD_SUCCEED;
627 #ifdef CONFIG_IPV6_ROUTER_PREF
628                 else if (!(neigh->nud_state & NUD_FAILED))
629                         ret = RT6_NUD_SUCCEED;
630                 else
631                         ret = RT6_NUD_FAIL_PROBE;
632 #endif
633                 read_unlock(&neigh->lock);
634         } else {
635                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
636                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
637         }
638         rcu_read_unlock_bh();
639
640         return ret;
641 }
642
643 static int rt6_score_route(struct rt6_info *rt, int oif,
644                            int strict)
645 {
646         int m;
647
648         m = rt6_check_dev(rt, oif);
649         if (!m && (strict & RT6_LOOKUP_F_IFACE))
650                 return RT6_NUD_FAIL_HARD;
651 #ifdef CONFIG_IPV6_ROUTER_PREF
652         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
653 #endif
654         if (strict & RT6_LOOKUP_F_REACHABLE) {
655                 int n = rt6_check_neigh(rt);
656                 if (n < 0)
657                         return n;
658         }
659         return m;
660 }
661
662 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
663                                    int *mpri, struct rt6_info *match,
664                                    bool *do_rr)
665 {
666         int m;
667         bool match_do_rr = false;
668         struct inet6_dev *idev = rt->rt6i_idev;
669         struct net_device *dev = rt->dst.dev;
670
671         if (dev && !netif_carrier_ok(dev) &&
672             idev->cnf.ignore_routes_with_linkdown)
673                 goto out;
674
675         if (rt6_check_expired(rt))
676                 goto out;
677
678         m = rt6_score_route(rt, oif, strict);
679         if (m == RT6_NUD_FAIL_DO_RR) {
680                 match_do_rr = true;
681                 m = 0; /* lowest valid score */
682         } else if (m == RT6_NUD_FAIL_HARD) {
683                 goto out;
684         }
685
686         if (strict & RT6_LOOKUP_F_REACHABLE)
687                 rt6_probe(rt);
688
689         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
690         if (m > *mpri) {
691                 *do_rr = match_do_rr;
692                 *mpri = m;
693                 match = rt;
694         }
695 out:
696         return match;
697 }
698
699 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
700                                      struct rt6_info *rr_head,
701                                      u32 metric, int oif, int strict,
702                                      bool *do_rr)
703 {
704         struct rt6_info *rt, *match, *cont;
705         int mpri = -1;
706
707         match = NULL;
708         cont = NULL;
709         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
710                 if (rt->rt6i_metric != metric) {
711                         cont = rt;
712                         break;
713                 }
714
715                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
716         }
717
718         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
719                 if (rt->rt6i_metric != metric) {
720                         cont = rt;
721                         break;
722                 }
723
724                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
725         }
726
727         if (match || !cont)
728                 return match;
729
730         for (rt = cont; rt; rt = rt->dst.rt6_next)
731                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
732
733         return match;
734 }
735
736 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
737 {
738         struct rt6_info *match, *rt0;
739         struct net *net;
740         bool do_rr = false;
741
742         rt0 = fn->rr_ptr;
743         if (!rt0)
744                 fn->rr_ptr = rt0 = fn->leaf;
745
746         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
747                              &do_rr);
748
749         if (do_rr) {
750                 struct rt6_info *next = rt0->dst.rt6_next;
751
752                 /* no entries matched; do round-robin */
753                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
754                         next = fn->leaf;
755
756                 if (next != rt0)
757                         fn->rr_ptr = next;
758         }
759
760         net = dev_net(rt0->dst.dev);
761         return match ? match : net->ipv6.ip6_null_entry;
762 }
763
764 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
765 {
766         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
767 }
768
769 #ifdef CONFIG_IPV6_ROUTE_INFO
770 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
771                   const struct in6_addr *gwaddr)
772 {
773         struct net *net = dev_net(dev);
774         struct route_info *rinfo = (struct route_info *) opt;
775         struct in6_addr prefix_buf, *prefix;
776         unsigned int pref;
777         unsigned long lifetime;
778         struct rt6_info *rt;
779
780         if (len < sizeof(struct route_info)) {
781                 return -EINVAL;
782         }
783
784         /* Sanity check for prefix_len and length */
785         if (rinfo->length > 3) {
786                 return -EINVAL;
787         } else if (rinfo->prefix_len > 128) {
788                 return -EINVAL;
789         } else if (rinfo->prefix_len > 64) {
790                 if (rinfo->length < 2) {
791                         return -EINVAL;
792                 }
793         } else if (rinfo->prefix_len > 0) {
794                 if (rinfo->length < 1) {
795                         return -EINVAL;
796                 }
797         }
798
799         pref = rinfo->route_pref;
800         if (pref == ICMPV6_ROUTER_PREF_INVALID)
801                 return -EINVAL;
802
803         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
804
805         if (rinfo->length == 3)
806                 prefix = (struct in6_addr *)rinfo->prefix;
807         else {
808                 /* this function is safe */
809                 ipv6_addr_prefix(&prefix_buf,
810                                  (struct in6_addr *)rinfo->prefix,
811                                  rinfo->prefix_len);
812                 prefix = &prefix_buf;
813         }
814
815         if (rinfo->prefix_len == 0)
816                 rt = rt6_get_dflt_router(gwaddr, dev);
817         else
818                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
819                                         gwaddr, dev->ifindex);
820
821         if (rt && !lifetime) {
822                 ip6_del_rt(rt);
823                 rt = NULL;
824         }
825
826         if (!rt && lifetime)
827                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
828                                         pref);
829         else if (rt)
830                 rt->rt6i_flags = RTF_ROUTEINFO |
831                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
832
833         if (rt) {
834                 if (!addrconf_finite_timeout(lifetime))
835                         rt6_clean_expires(rt);
836                 else
837                         rt6_set_expires(rt, jiffies + HZ * lifetime);
838
839                 ip6_rt_put(rt);
840         }
841         return 0;
842 }
843 #endif
844
845 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
846                                         struct in6_addr *saddr)
847 {
848         struct fib6_node *pn;
849         while (1) {
850                 if (fn->fn_flags & RTN_TL_ROOT)
851                         return NULL;
852                 pn = fn->parent;
853                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
854                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
855                 else
856                         fn = pn;
857                 if (fn->fn_flags & RTN_RTINFO)
858                         return fn;
859         }
860 }
861
862 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
863                                              struct fib6_table *table,
864                                              struct flowi6 *fl6, int flags)
865 {
866         struct fib6_node *fn;
867         struct rt6_info *rt;
868
869         read_lock_bh(&table->tb6_lock);
870         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
871 restart:
872         rt = fn->leaf;
873         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
874         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
875                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
876         if (rt == net->ipv6.ip6_null_entry) {
877                 fn = fib6_backtrack(fn, &fl6->saddr);
878                 if (fn)
879                         goto restart;
880         }
881         dst_use(&rt->dst, jiffies);
882         read_unlock_bh(&table->tb6_lock);
883         return rt;
884
885 }
886
887 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
888                                     int flags)
889 {
890         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
891 }
892 EXPORT_SYMBOL_GPL(ip6_route_lookup);
893
894 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
895                             const struct in6_addr *saddr, int oif, int strict)
896 {
897         struct flowi6 fl6 = {
898                 .flowi6_oif = oif,
899                 .daddr = *daddr,
900         };
901         struct dst_entry *dst;
902         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
903
904         if (saddr) {
905                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
906                 flags |= RT6_LOOKUP_F_HAS_SADDR;
907         }
908
909         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
910         if (dst->error == 0)
911                 return (struct rt6_info *) dst;
912
913         dst_release(dst);
914
915         return NULL;
916 }
917 EXPORT_SYMBOL(rt6_lookup);
918
919 /* ip6_ins_rt is called with FREE table->tb6_lock.
920    It takes new route entry, the addition fails by any reason the
921    route is freed. In any case, if caller does not hold it, it may
922    be destroyed.
923  */
924
925 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
926                         struct mx6_config *mxc)
927 {
928         int err;
929         struct fib6_table *table;
930
931         table = rt->rt6i_table;
932         write_lock_bh(&table->tb6_lock);
933         err = fib6_add(&table->tb6_root, rt, info, mxc);
934         write_unlock_bh(&table->tb6_lock);
935
936         return err;
937 }
938
939 int ip6_ins_rt(struct rt6_info *rt)
940 {
941         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
942         struct mx6_config mxc = { .mx = NULL, };
943
944         return __ip6_ins_rt(rt, &info, &mxc);
945 }
946
947 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
948                                            const struct in6_addr *daddr,
949                                            const struct in6_addr *saddr)
950 {
951         struct rt6_info *rt;
952
953         /*
954          *      Clone the route.
955          */
956
957         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
958                 ort = (struct rt6_info *)ort->dst.from;
959
960         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
961
962         if (!rt)
963                 return NULL;
964
965         ip6_rt_copy_init(rt, ort);
966         rt->rt6i_flags |= RTF_CACHE;
967         rt->rt6i_metric = 0;
968         rt->dst.flags |= DST_HOST;
969         rt->rt6i_dst.addr = *daddr;
970         rt->rt6i_dst.plen = 128;
971
972         if (!rt6_is_gw_or_nonexthop(ort)) {
973                 if (ort->rt6i_dst.plen != 128 &&
974                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
975                         rt->rt6i_flags |= RTF_ANYCAST;
976 #ifdef CONFIG_IPV6_SUBTREES
977                 if (rt->rt6i_src.plen && saddr) {
978                         rt->rt6i_src.addr = *saddr;
979                         rt->rt6i_src.plen = 128;
980                 }
981 #endif
982         }
983
984         return rt;
985 }
986
987 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
988 {
989         struct rt6_info *pcpu_rt;
990
991         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
992                                   rt->dst.dev, rt->dst.flags);
993
994         if (!pcpu_rt)
995                 return NULL;
996         ip6_rt_copy_init(pcpu_rt, rt);
997         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
998         pcpu_rt->rt6i_flags |= RTF_PCPU;
999         return pcpu_rt;
1000 }
1001
1002 /* It should be called with read_lock_bh(&tb6_lock) acquired */
1003 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
1004 {
1005         struct rt6_info *pcpu_rt, **p;
1006
1007         p = this_cpu_ptr(rt->rt6i_pcpu);
1008         pcpu_rt = *p;
1009
1010         if (pcpu_rt) {
1011                 dst_hold(&pcpu_rt->dst);
1012                 rt6_dst_from_metrics_check(pcpu_rt);
1013         }
1014         return pcpu_rt;
1015 }
1016
1017 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1018 {
1019         struct fib6_table *table = rt->rt6i_table;
1020         struct rt6_info *pcpu_rt, *prev, **p;
1021
1022         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1023         if (!pcpu_rt) {
1024                 struct net *net = dev_net(rt->dst.dev);
1025
1026                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1027                 return net->ipv6.ip6_null_entry;
1028         }
1029
1030         read_lock_bh(&table->tb6_lock);
1031         if (rt->rt6i_pcpu) {
1032                 p = this_cpu_ptr(rt->rt6i_pcpu);
1033                 prev = cmpxchg(p, NULL, pcpu_rt);
1034                 if (prev) {
1035                         /* If someone did it before us, return prev instead */
1036                         dst_destroy(&pcpu_rt->dst);
1037                         pcpu_rt = prev;
1038                 }
1039         } else {
1040                 /* rt has been removed from the fib6 tree
1041                  * before we have a chance to acquire the read_lock.
1042                  * In this case, don't brother to create a pcpu rt
1043                  * since rt is going away anyway.  The next
1044                  * dst_check() will trigger a re-lookup.
1045                  */
1046                 dst_destroy(&pcpu_rt->dst);
1047                 pcpu_rt = rt;
1048         }
1049         dst_hold(&pcpu_rt->dst);
1050         rt6_dst_from_metrics_check(pcpu_rt);
1051         read_unlock_bh(&table->tb6_lock);
1052         return pcpu_rt;
1053 }
1054
1055 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1056                                       struct flowi6 *fl6, int flags)
1057 {
1058         struct fib6_node *fn, *saved_fn;
1059         struct rt6_info *rt;
1060         int strict = 0;
1061
1062         strict |= flags & RT6_LOOKUP_F_IFACE;
1063         if (net->ipv6.devconf_all->forwarding == 0)
1064                 strict |= RT6_LOOKUP_F_REACHABLE;
1065
1066         read_lock_bh(&table->tb6_lock);
1067
1068         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1069         saved_fn = fn;
1070
1071         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1072                 oif = 0;
1073
1074 redo_rt6_select:
1075         rt = rt6_select(fn, oif, strict);
1076         if (rt->rt6i_nsiblings)
1077                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1078         if (rt == net->ipv6.ip6_null_entry) {
1079                 fn = fib6_backtrack(fn, &fl6->saddr);
1080                 if (fn)
1081                         goto redo_rt6_select;
1082                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1083                         /* also consider unreachable route */
1084                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1085                         fn = saved_fn;
1086                         goto redo_rt6_select;
1087                 }
1088         }
1089
1090
1091         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1092                 dst_use(&rt->dst, jiffies);
1093                 read_unlock_bh(&table->tb6_lock);
1094
1095                 rt6_dst_from_metrics_check(rt);
1096                 return rt;
1097         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1098                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1099                 /* Create a RTF_CACHE clone which will not be
1100                  * owned by the fib6 tree.  It is for the special case where
1101                  * the daddr in the skb during the neighbor look-up is different
1102                  * from the fl6->daddr used to look-up route here.
1103                  */
1104
1105                 struct rt6_info *uncached_rt;
1106
1107                 dst_use(&rt->dst, jiffies);
1108                 read_unlock_bh(&table->tb6_lock);
1109
1110                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1111                 dst_release(&rt->dst);
1112
1113                 if (uncached_rt)
1114                         rt6_uncached_list_add(uncached_rt);
1115                 else
1116                         uncached_rt = net->ipv6.ip6_null_entry;
1117
1118                 dst_hold(&uncached_rt->dst);
1119                 return uncached_rt;
1120
1121         } else {
1122                 /* Get a percpu copy */
1123
1124                 struct rt6_info *pcpu_rt;
1125
1126                 rt->dst.lastuse = jiffies;
1127                 rt->dst.__use++;
1128                 pcpu_rt = rt6_get_pcpu_route(rt);
1129
1130                 if (pcpu_rt) {
1131                         read_unlock_bh(&table->tb6_lock);
1132                 } else {
1133                         /* We have to do the read_unlock first
1134                          * because rt6_make_pcpu_route() may trigger
1135                          * ip6_dst_gc() which will take the write_lock.
1136                          */
1137                         dst_hold(&rt->dst);
1138                         read_unlock_bh(&table->tb6_lock);
1139                         pcpu_rt = rt6_make_pcpu_route(rt);
1140                         dst_release(&rt->dst);
1141                 }
1142
1143                 return pcpu_rt;
1144
1145         }
1146 }
1147
1148 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1149                                             struct flowi6 *fl6, int flags)
1150 {
1151         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1152 }
1153
1154 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1155                                                 struct net_device *dev,
1156                                                 struct flowi6 *fl6, int flags)
1157 {
1158         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1159                 flags |= RT6_LOOKUP_F_IFACE;
1160
1161         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1162 }
1163
1164 void ip6_route_input(struct sk_buff *skb)
1165 {
1166         const struct ipv6hdr *iph = ipv6_hdr(skb);
1167         struct net *net = dev_net(skb->dev);
1168         int flags = RT6_LOOKUP_F_HAS_SADDR;
1169         struct ip_tunnel_info *tun_info;
1170         struct flowi6 fl6 = {
1171                 .flowi6_iif = skb->dev->ifindex,
1172                 .daddr = iph->daddr,
1173                 .saddr = iph->saddr,
1174                 .flowlabel = ip6_flowinfo(iph),
1175                 .flowi6_mark = skb->mark,
1176                 .flowi6_proto = iph->nexthdr,
1177         };
1178
1179         tun_info = skb_tunnel_info(skb);
1180         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1181                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1182         skb_dst_drop(skb);
1183         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1184 }
1185
1186 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1187                                              struct flowi6 *fl6, int flags)
1188 {
1189         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1190 }
1191
1192 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1193                                     struct flowi6 *fl6)
1194 {
1195         int flags = 0;
1196
1197         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1198
1199         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1200             fl6->flowi6_oif)
1201                 flags |= RT6_LOOKUP_F_IFACE;
1202
1203         if (!ipv6_addr_any(&fl6->saddr))
1204                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1205         else if (sk)
1206                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1207
1208         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1209 }
1210 EXPORT_SYMBOL(ip6_route_output);
1211
1212 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1213 {
1214         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1215         struct dst_entry *new = NULL;
1216
1217         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1218         if (rt) {
1219                 rt6_info_init(rt);
1220
1221                 new = &rt->dst;
1222                 new->__use = 1;
1223                 new->input = dst_discard;
1224                 new->output = dst_discard_sk;
1225
1226                 dst_copy_metrics(new, &ort->dst);
1227                 rt->rt6i_idev = ort->rt6i_idev;
1228                 if (rt->rt6i_idev)
1229                         in6_dev_hold(rt->rt6i_idev);
1230
1231                 rt->rt6i_gateway = ort->rt6i_gateway;
1232                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1233                 rt->rt6i_metric = 0;
1234
1235                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1236 #ifdef CONFIG_IPV6_SUBTREES
1237                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1238 #endif
1239
1240                 dst_free(new);
1241         }
1242
1243         dst_release(dst_orig);
1244         return new ? new : ERR_PTR(-ENOMEM);
1245 }
1246
1247 /*
1248  *      Destination cache support functions
1249  */
1250
1251 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1252 {
1253         if (rt->dst.from &&
1254             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1255                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1256 }
1257
1258 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1259 {
1260         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1261                 return NULL;
1262
1263         if (rt6_check_expired(rt))
1264                 return NULL;
1265
1266         return &rt->dst;
1267 }
1268
1269 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1270 {
1271         if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1272             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1273                 return &rt->dst;
1274         else
1275                 return NULL;
1276 }
1277
1278 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1279 {
1280         struct rt6_info *rt;
1281
1282         rt = (struct rt6_info *) dst;
1283
1284         /* All IPV6 dsts are created with ->obsolete set to the value
1285          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1286          * into this function always.
1287          */
1288
1289         rt6_dst_from_metrics_check(rt);
1290
1291         if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1292                 return rt6_dst_from_check(rt, cookie);
1293         else
1294                 return rt6_check(rt, cookie);
1295 }
1296
1297 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1298 {
1299         struct rt6_info *rt = (struct rt6_info *) dst;
1300
1301         if (rt) {
1302                 if (rt->rt6i_flags & RTF_CACHE) {
1303                         if (rt6_check_expired(rt)) {
1304                                 ip6_del_rt(rt);
1305                                 dst = NULL;
1306                         }
1307                 } else {
1308                         dst_release(dst);
1309                         dst = NULL;
1310                 }
1311         }
1312         return dst;
1313 }
1314
1315 static void ip6_link_failure(struct sk_buff *skb)
1316 {
1317         struct rt6_info *rt;
1318
1319         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1320
1321         rt = (struct rt6_info *) skb_dst(skb);
1322         if (rt) {
1323                 if (rt->rt6i_flags & RTF_CACHE) {
1324                         dst_hold(&rt->dst);
1325                         ip6_del_rt(rt);
1326                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1327                         rt->rt6i_node->fn_sernum = -1;
1328                 }
1329         }
1330 }
1331
1332 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1333 {
1334         struct net *net = dev_net(rt->dst.dev);
1335
1336         rt->rt6i_flags |= RTF_MODIFIED;
1337         rt->rt6i_pmtu = mtu;
1338         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1339 }
1340
1341 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1342                                  const struct ipv6hdr *iph, u32 mtu)
1343 {
1344         struct rt6_info *rt6 = (struct rt6_info *)dst;
1345
1346         if (rt6->rt6i_flags & RTF_LOCAL)
1347                 return;
1348
1349         dst_confirm(dst);
1350         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1351         if (mtu >= dst_mtu(dst))
1352                 return;
1353
1354         if (rt6->rt6i_flags & RTF_CACHE) {
1355                 rt6_do_update_pmtu(rt6, mtu);
1356         } else {
1357                 const struct in6_addr *daddr, *saddr;
1358                 struct rt6_info *nrt6;
1359
1360                 if (iph) {
1361                         daddr = &iph->daddr;
1362                         saddr = &iph->saddr;
1363                 } else if (sk) {
1364                         daddr = &sk->sk_v6_daddr;
1365                         saddr = &inet6_sk(sk)->saddr;
1366                 } else {
1367                         return;
1368                 }
1369                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1370                 if (nrt6) {
1371                         rt6_do_update_pmtu(nrt6, mtu);
1372
1373                         /* ip6_ins_rt(nrt6) will bump the
1374                          * rt6->rt6i_node->fn_sernum
1375                          * which will fail the next rt6_check() and
1376                          * invalidate the sk->sk_dst_cache.
1377                          */
1378                         ip6_ins_rt(nrt6);
1379                 }
1380         }
1381 }
1382
1383 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1384                                struct sk_buff *skb, u32 mtu)
1385 {
1386         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1387 }
1388
1389 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1390                      int oif, u32 mark)
1391 {
1392         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1393         struct dst_entry *dst;
1394         struct flowi6 fl6;
1395
1396         memset(&fl6, 0, sizeof(fl6));
1397         fl6.flowi6_oif = oif;
1398         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1399         fl6.daddr = iph->daddr;
1400         fl6.saddr = iph->saddr;
1401         fl6.flowlabel = ip6_flowinfo(iph);
1402
1403         dst = ip6_route_output(net, NULL, &fl6);
1404         if (!dst->error)
1405                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1406         dst_release(dst);
1407 }
1408 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1409
1410 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1411 {
1412         ip6_update_pmtu(skb, sock_net(sk), mtu,
1413                         sk->sk_bound_dev_if, sk->sk_mark);
1414 }
1415 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1416
1417 /* Handle redirects */
1418 struct ip6rd_flowi {
1419         struct flowi6 fl6;
1420         struct in6_addr gateway;
1421 };
1422
1423 static struct rt6_info *__ip6_route_redirect(struct net *net,
1424                                              struct fib6_table *table,
1425                                              struct flowi6 *fl6,
1426                                              int flags)
1427 {
1428         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1429         struct rt6_info *rt;
1430         struct fib6_node *fn;
1431
1432         /* Get the "current" route for this destination and
1433          * check if the redirect has come from approriate router.
1434          *
1435          * RFC 4861 specifies that redirects should only be
1436          * accepted if they come from the nexthop to the target.
1437          * Due to the way the routes are chosen, this notion
1438          * is a bit fuzzy and one might need to check all possible
1439          * routes.
1440          */
1441
1442         read_lock_bh(&table->tb6_lock);
1443         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1444 restart:
1445         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1446                 if (rt6_check_expired(rt))
1447                         continue;
1448                 if (rt->dst.error)
1449                         break;
1450                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1451                         continue;
1452                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1453                         continue;
1454                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1455                         continue;
1456                 break;
1457         }
1458
1459         if (!rt)
1460                 rt = net->ipv6.ip6_null_entry;
1461         else if (rt->dst.error) {
1462                 rt = net->ipv6.ip6_null_entry;
1463                 goto out;
1464         }
1465
1466         if (rt == net->ipv6.ip6_null_entry) {
1467                 fn = fib6_backtrack(fn, &fl6->saddr);
1468                 if (fn)
1469                         goto restart;
1470         }
1471
1472 out:
1473         dst_hold(&rt->dst);
1474
1475         read_unlock_bh(&table->tb6_lock);
1476
1477         return rt;
1478 };
1479
1480 static struct dst_entry *ip6_route_redirect(struct net *net,
1481                                         const struct flowi6 *fl6,
1482                                         const struct in6_addr *gateway)
1483 {
1484         int flags = RT6_LOOKUP_F_HAS_SADDR;
1485         struct ip6rd_flowi rdfl;
1486
1487         rdfl.fl6 = *fl6;
1488         rdfl.gateway = *gateway;
1489
1490         return fib6_rule_lookup(net, &rdfl.fl6,
1491                                 flags, __ip6_route_redirect);
1492 }
1493
1494 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1495 {
1496         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1497         struct dst_entry *dst;
1498         struct flowi6 fl6;
1499
1500         memset(&fl6, 0, sizeof(fl6));
1501         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1502         fl6.flowi6_oif = oif;
1503         fl6.flowi6_mark = mark;
1504         fl6.daddr = iph->daddr;
1505         fl6.saddr = iph->saddr;
1506         fl6.flowlabel = ip6_flowinfo(iph);
1507
1508         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1509         rt6_do_redirect(dst, NULL, skb);
1510         dst_release(dst);
1511 }
1512 EXPORT_SYMBOL_GPL(ip6_redirect);
1513
1514 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1515                             u32 mark)
1516 {
1517         const struct ipv6hdr *iph = ipv6_hdr(skb);
1518         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1519         struct dst_entry *dst;
1520         struct flowi6 fl6;
1521
1522         memset(&fl6, 0, sizeof(fl6));
1523         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1524         fl6.flowi6_oif = oif;
1525         fl6.flowi6_mark = mark;
1526         fl6.daddr = msg->dest;
1527         fl6.saddr = iph->daddr;
1528
1529         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1530         rt6_do_redirect(dst, NULL, skb);
1531         dst_release(dst);
1532 }
1533
1534 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1535 {
1536         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1537 }
1538 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1539
1540 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1541 {
1542         struct net_device *dev = dst->dev;
1543         unsigned int mtu = dst_mtu(dst);
1544         struct net *net = dev_net(dev);
1545
1546         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1547
1548         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1549                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1550
1551         /*
1552          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1553          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1554          * IPV6_MAXPLEN is also valid and means: "any MSS,
1555          * rely only on pmtu discovery"
1556          */
1557         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1558                 mtu = IPV6_MAXPLEN;
1559         return mtu;
1560 }
1561
1562 static unsigned int ip6_mtu(const struct dst_entry *dst)
1563 {
1564         const struct rt6_info *rt = (const struct rt6_info *)dst;
1565         unsigned int mtu = rt->rt6i_pmtu;
1566         struct inet6_dev *idev;
1567
1568         if (mtu)
1569                 goto out;
1570
1571         mtu = dst_metric_raw(dst, RTAX_MTU);
1572         if (mtu)
1573                 goto out;
1574
1575         mtu = IPV6_MIN_MTU;
1576
1577         rcu_read_lock();
1578         idev = __in6_dev_get(dst->dev);
1579         if (idev)
1580                 mtu = idev->cnf.mtu6;
1581         rcu_read_unlock();
1582
1583 out:
1584         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1585 }
1586
1587 static struct dst_entry *icmp6_dst_gc_list;
1588 static DEFINE_SPINLOCK(icmp6_dst_lock);
1589
1590 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1591                                   struct flowi6 *fl6)
1592 {
1593         struct dst_entry *dst;
1594         struct rt6_info *rt;
1595         struct inet6_dev *idev = in6_dev_get(dev);
1596         struct net *net = dev_net(dev);
1597
1598         if (unlikely(!idev))
1599                 return ERR_PTR(-ENODEV);
1600
1601         rt = ip6_dst_alloc(net, dev, 0);
1602         if (unlikely(!rt)) {
1603                 in6_dev_put(idev);
1604                 dst = ERR_PTR(-ENOMEM);
1605                 goto out;
1606         }
1607
1608         rt->dst.flags |= DST_HOST;
1609         rt->dst.output  = ip6_output;
1610         atomic_set(&rt->dst.__refcnt, 1);
1611         rt->rt6i_gateway  = fl6->daddr;
1612         rt->rt6i_dst.addr = fl6->daddr;
1613         rt->rt6i_dst.plen = 128;
1614         rt->rt6i_idev     = idev;
1615         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1616
1617         spin_lock_bh(&icmp6_dst_lock);
1618         rt->dst.next = icmp6_dst_gc_list;
1619         icmp6_dst_gc_list = &rt->dst;
1620         spin_unlock_bh(&icmp6_dst_lock);
1621
1622         fib6_force_start_gc(net);
1623
1624         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1625
1626 out:
1627         return dst;
1628 }
1629
1630 int icmp6_dst_gc(void)
1631 {
1632         struct dst_entry *dst, **pprev;
1633         int more = 0;
1634
1635         spin_lock_bh(&icmp6_dst_lock);
1636         pprev = &icmp6_dst_gc_list;
1637
1638         while ((dst = *pprev) != NULL) {
1639                 if (!atomic_read(&dst->__refcnt)) {
1640                         *pprev = dst->next;
1641                         dst_free(dst);
1642                 } else {
1643                         pprev = &dst->next;
1644                         ++more;
1645                 }
1646         }
1647
1648         spin_unlock_bh(&icmp6_dst_lock);
1649
1650         return more;
1651 }
1652
1653 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1654                             void *arg)
1655 {
1656         struct dst_entry *dst, **pprev;
1657
1658         spin_lock_bh(&icmp6_dst_lock);
1659         pprev = &icmp6_dst_gc_list;
1660         while ((dst = *pprev) != NULL) {
1661                 struct rt6_info *rt = (struct rt6_info *) dst;
1662                 if (func(rt, arg)) {
1663                         *pprev = dst->next;
1664                         dst_free(dst);
1665                 } else {
1666                         pprev = &dst->next;
1667                 }
1668         }
1669         spin_unlock_bh(&icmp6_dst_lock);
1670 }
1671
1672 static int ip6_dst_gc(struct dst_ops *ops)
1673 {
1674         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1675         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1676         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1677         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1678         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1679         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1680         int entries;
1681
1682         entries = dst_entries_get_fast(ops);
1683         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1684             entries <= rt_max_size)
1685                 goto out;
1686
1687         net->ipv6.ip6_rt_gc_expire++;
1688         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1689         entries = dst_entries_get_slow(ops);
1690         if (entries < ops->gc_thresh)
1691                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1692 out:
1693         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1694         return entries > rt_max_size;
1695 }
1696
1697 static int ip6_convert_metrics(struct mx6_config *mxc,
1698                                const struct fib6_config *cfg)
1699 {
1700         bool ecn_ca = false;
1701         struct nlattr *nla;
1702         int remaining;
1703         u32 *mp;
1704
1705         if (!cfg->fc_mx)
1706                 return 0;
1707
1708         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1709         if (unlikely(!mp))
1710                 return -ENOMEM;
1711
1712         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1713                 int type = nla_type(nla);
1714                 u32 val;
1715
1716                 if (!type)
1717                         continue;
1718                 if (unlikely(type > RTAX_MAX))
1719                         goto err;
1720
1721                 if (type == RTAX_CC_ALGO) {
1722                         char tmp[TCP_CA_NAME_MAX];
1723
1724                         nla_strlcpy(tmp, nla, sizeof(tmp));
1725                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1726                         if (val == TCP_CA_UNSPEC)
1727                                 goto err;
1728                 } else {
1729                         val = nla_get_u32(nla);
1730                 }
1731                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1732                         goto err;
1733
1734                 mp[type - 1] = val;
1735                 __set_bit(type - 1, mxc->mx_valid);
1736         }
1737
1738         if (ecn_ca) {
1739                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1740                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1741         }
1742
1743         mxc->mx = mp;
1744         return 0;
1745  err:
1746         kfree(mp);
1747         return -EINVAL;
1748 }
1749
1750 int ip6_route_info_create(struct fib6_config *cfg, struct rt6_info **rt_ret)
1751 {
1752         int err;
1753         struct net *net = cfg->fc_nlinfo.nl_net;
1754         struct rt6_info *rt = NULL;
1755         struct net_device *dev = NULL;
1756         struct inet6_dev *idev = NULL;
1757         struct fib6_table *table;
1758         int addr_type;
1759
1760         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1761                 return -EINVAL;
1762 #ifndef CONFIG_IPV6_SUBTREES
1763         if (cfg->fc_src_len)
1764                 return -EINVAL;
1765 #endif
1766         if (cfg->fc_ifindex) {
1767                 err = -ENODEV;
1768                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1769                 if (!dev)
1770                         goto out;
1771                 idev = in6_dev_get(dev);
1772                 if (!idev)
1773                         goto out;
1774         }
1775
1776         if (cfg->fc_metric == 0)
1777                 cfg->fc_metric = IP6_RT_PRIO_USER;
1778
1779         err = -ENOBUFS;
1780         if (cfg->fc_nlinfo.nlh &&
1781             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1782                 table = fib6_get_table(net, cfg->fc_table);
1783                 if (!table) {
1784                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1785                         table = fib6_new_table(net, cfg->fc_table);
1786                 }
1787         } else {
1788                 table = fib6_new_table(net, cfg->fc_table);
1789         }
1790
1791         if (!table)
1792                 goto out;
1793
1794         rt = ip6_dst_alloc(net, NULL,
1795                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1796
1797         if (!rt) {
1798                 err = -ENOMEM;
1799                 goto out;
1800         }
1801
1802         if (cfg->fc_flags & RTF_EXPIRES)
1803                 rt6_set_expires(rt, jiffies +
1804                                 clock_t_to_jiffies(cfg->fc_expires));
1805         else
1806                 rt6_clean_expires(rt);
1807
1808         if (cfg->fc_protocol == RTPROT_UNSPEC)
1809                 cfg->fc_protocol = RTPROT_BOOT;
1810         rt->rt6i_protocol = cfg->fc_protocol;
1811
1812         addr_type = ipv6_addr_type(&cfg->fc_dst);
1813
1814         if (addr_type & IPV6_ADDR_MULTICAST)
1815                 rt->dst.input = ip6_mc_input;
1816         else if (cfg->fc_flags & RTF_LOCAL)
1817                 rt->dst.input = ip6_input;
1818         else
1819                 rt->dst.input = ip6_forward;
1820
1821         rt->dst.output = ip6_output;
1822
1823         if (cfg->fc_encap) {
1824                 struct lwtunnel_state *lwtstate;
1825
1826                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1827                                            cfg->fc_encap, AF_INET6, cfg,
1828                                            &lwtstate);
1829                 if (err)
1830                         goto out;
1831                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1832                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1833                         rt->dst.lwtstate->orig_output = rt->dst.output;
1834                         rt->dst.output = lwtunnel_output;
1835                 }
1836                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1837                         rt->dst.lwtstate->orig_input = rt->dst.input;
1838                         rt->dst.input = lwtunnel_input;
1839                 }
1840         }
1841
1842         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1843         rt->rt6i_dst.plen = cfg->fc_dst_len;
1844         if (rt->rt6i_dst.plen == 128)
1845                 rt->dst.flags |= DST_HOST;
1846
1847 #ifdef CONFIG_IPV6_SUBTREES
1848         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1849         rt->rt6i_src.plen = cfg->fc_src_len;
1850 #endif
1851
1852         rt->rt6i_metric = cfg->fc_metric;
1853
1854         /* We cannot add true routes via loopback here,
1855            they would result in kernel looping; promote them to reject routes
1856          */
1857         if ((cfg->fc_flags & RTF_REJECT) ||
1858             (dev && (dev->flags & IFF_LOOPBACK) &&
1859              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1860              !(cfg->fc_flags & RTF_LOCAL))) {
1861                 /* hold loopback dev/idev if we haven't done so. */
1862                 if (dev != net->loopback_dev) {
1863                         if (dev) {
1864                                 dev_put(dev);
1865                                 in6_dev_put(idev);
1866                         }
1867                         dev = net->loopback_dev;
1868                         dev_hold(dev);
1869                         idev = in6_dev_get(dev);
1870                         if (!idev) {
1871                                 err = -ENODEV;
1872                                 goto out;
1873                         }
1874                 }
1875                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1876                 switch (cfg->fc_type) {
1877                 case RTN_BLACKHOLE:
1878                         rt->dst.error = -EINVAL;
1879                         rt->dst.output = dst_discard_sk;
1880                         rt->dst.input = dst_discard;
1881                         break;
1882                 case RTN_PROHIBIT:
1883                         rt->dst.error = -EACCES;
1884                         rt->dst.output = ip6_pkt_prohibit_out;
1885                         rt->dst.input = ip6_pkt_prohibit;
1886                         break;
1887                 case RTN_THROW:
1888                 case RTN_UNREACHABLE:
1889                 default:
1890                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1891                                         : (cfg->fc_type == RTN_UNREACHABLE)
1892                                         ? -EHOSTUNREACH : -ENETUNREACH;
1893                         rt->dst.output = ip6_pkt_discard_out;
1894                         rt->dst.input = ip6_pkt_discard;
1895                         break;
1896                 }
1897                 goto install_route;
1898         }
1899
1900         if (cfg->fc_flags & RTF_GATEWAY) {
1901                 const struct in6_addr *gw_addr;
1902                 int gwa_type;
1903
1904                 gw_addr = &cfg->fc_gateway;
1905                 gwa_type = ipv6_addr_type(gw_addr);
1906
1907                 /* if gw_addr is local we will fail to detect this in case
1908                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1909                  * will return already-added prefix route via interface that
1910                  * prefix route was assigned to, which might be non-loopback.
1911                  */
1912                 err = -EINVAL;
1913                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1914                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1915                                             dev : NULL, 0, 0))
1916                         goto out;
1917
1918                 rt->rt6i_gateway = *gw_addr;
1919
1920                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1921                         struct rt6_info *grt;
1922
1923                         /* IPv6 strictly inhibits using not link-local
1924                            addresses as nexthop address.
1925                            Otherwise, router will not able to send redirects.
1926                            It is very good, but in some (rare!) circumstances
1927                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1928                            some exceptions. --ANK
1929                          */
1930                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1931                                 goto out;
1932
1933                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1934
1935                         err = -EHOSTUNREACH;
1936                         if (!grt)
1937                                 goto out;
1938                         if (dev) {
1939                                 if (dev != grt->dst.dev) {
1940                                         ip6_rt_put(grt);
1941                                         goto out;
1942                                 }
1943                         } else {
1944                                 dev = grt->dst.dev;
1945                                 idev = grt->rt6i_idev;
1946                                 dev_hold(dev);
1947                                 in6_dev_hold(grt->rt6i_idev);
1948                         }
1949                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1950                                 err = 0;
1951                         ip6_rt_put(grt);
1952
1953                         if (err)
1954                                 goto out;
1955                 }
1956                 err = -EINVAL;
1957                 if (!dev || (dev->flags & IFF_LOOPBACK))
1958                         goto out;
1959         }
1960
1961         err = -ENODEV;
1962         if (!dev)
1963                 goto out;
1964
1965         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1966                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1967                         err = -EINVAL;
1968                         goto out;
1969                 }
1970                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1971                 rt->rt6i_prefsrc.plen = 128;
1972         } else
1973                 rt->rt6i_prefsrc.plen = 0;
1974
1975         rt->rt6i_flags = cfg->fc_flags;
1976
1977 install_route:
1978         rt->dst.dev = dev;
1979         rt->rt6i_idev = idev;
1980         rt->rt6i_table = table;
1981
1982         cfg->fc_nlinfo.nl_net = dev_net(dev);
1983
1984         *rt_ret = rt;
1985
1986         return 0;
1987 out:
1988         if (dev)
1989                 dev_put(dev);
1990         if (idev)
1991                 in6_dev_put(idev);
1992         if (rt)
1993                 dst_free(&rt->dst);
1994
1995         *rt_ret = NULL;
1996
1997         return err;
1998 }
1999
2000 int ip6_route_add(struct fib6_config *cfg)
2001 {
2002         struct mx6_config mxc = { .mx = NULL, };
2003         struct rt6_info *rt = NULL;
2004         int err;
2005
2006         err = ip6_route_info_create(cfg, &rt);
2007         if (err)
2008                 goto out;
2009
2010         err = ip6_convert_metrics(&mxc, cfg);
2011         if (err)
2012                 goto out;
2013
2014         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2015
2016         kfree(mxc.mx);
2017
2018         return err;
2019 out:
2020         if (rt)
2021                 dst_free(&rt->dst);
2022
2023         return err;
2024 }
2025
2026 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2027 {
2028         int err;
2029         struct fib6_table *table;
2030         struct net *net = dev_net(rt->dst.dev);
2031
2032         if (rt == net->ipv6.ip6_null_entry ||
2033             rt->dst.flags & DST_NOCACHE) {
2034                 err = -ENOENT;
2035                 goto out;
2036         }
2037
2038         table = rt->rt6i_table;
2039         write_lock_bh(&table->tb6_lock);
2040         err = fib6_del(rt, info);
2041         write_unlock_bh(&table->tb6_lock);
2042
2043 out:
2044         ip6_rt_put(rt);
2045         return err;
2046 }
2047
2048 int ip6_del_rt(struct rt6_info *rt)
2049 {
2050         struct nl_info info = {
2051                 .nl_net = dev_net(rt->dst.dev),
2052         };
2053         return __ip6_del_rt(rt, &info);
2054 }
2055
2056 static int ip6_route_del(struct fib6_config *cfg)
2057 {
2058         struct fib6_table *table;
2059         struct fib6_node *fn;
2060         struct rt6_info *rt;
2061         int err = -ESRCH;
2062
2063         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2064         if (!table)
2065                 return err;
2066
2067         read_lock_bh(&table->tb6_lock);
2068
2069         fn = fib6_locate(&table->tb6_root,
2070                          &cfg->fc_dst, cfg->fc_dst_len,
2071                          &cfg->fc_src, cfg->fc_src_len);
2072
2073         if (fn) {
2074                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2075                         if ((rt->rt6i_flags & RTF_CACHE) &&
2076                             !(cfg->fc_flags & RTF_CACHE))
2077                                 continue;
2078                         if (cfg->fc_ifindex &&
2079                             (!rt->dst.dev ||
2080                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2081                                 continue;
2082                         if (cfg->fc_flags & RTF_GATEWAY &&
2083                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2084                                 continue;
2085                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2086                                 continue;
2087                         dst_hold(&rt->dst);
2088                         read_unlock_bh(&table->tb6_lock);
2089
2090                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2091                 }
2092         }
2093         read_unlock_bh(&table->tb6_lock);
2094
2095         return err;
2096 }
2097
2098 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2099 {
2100         struct net *net = dev_net(skb->dev);
2101         struct netevent_redirect netevent;
2102         struct rt6_info *rt, *nrt = NULL;
2103         struct ndisc_options ndopts;
2104         struct inet6_dev *in6_dev;
2105         struct neighbour *neigh;
2106         struct rd_msg *msg;
2107         int optlen, on_link;
2108         u8 *lladdr;
2109
2110         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2111         optlen -= sizeof(*msg);
2112
2113         if (optlen < 0) {
2114                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2115                 return;
2116         }
2117
2118         msg = (struct rd_msg *)icmp6_hdr(skb);
2119
2120         if (ipv6_addr_is_multicast(&msg->dest)) {
2121                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2122                 return;
2123         }
2124
2125         on_link = 0;
2126         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2127                 on_link = 1;
2128         } else if (ipv6_addr_type(&msg->target) !=
2129                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2130                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2131                 return;
2132         }
2133
2134         in6_dev = __in6_dev_get(skb->dev);
2135         if (!in6_dev)
2136                 return;
2137         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2138                 return;
2139
2140         /* RFC2461 8.1:
2141          *      The IP source address of the Redirect MUST be the same as the current
2142          *      first-hop router for the specified ICMP Destination Address.
2143          */
2144
2145         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2146                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2147                 return;
2148         }
2149
2150         lladdr = NULL;
2151         if (ndopts.nd_opts_tgt_lladdr) {
2152                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2153                                              skb->dev);
2154                 if (!lladdr) {
2155                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2156                         return;
2157                 }
2158         }
2159
2160         rt = (struct rt6_info *) dst;
2161         if (rt == net->ipv6.ip6_null_entry) {
2162                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2163                 return;
2164         }
2165
2166         /* Redirect received -> path was valid.
2167          * Look, redirects are sent only in response to data packets,
2168          * so that this nexthop apparently is reachable. --ANK
2169          */
2170         dst_confirm(&rt->dst);
2171
2172         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2173         if (!neigh)
2174                 return;
2175
2176         /*
2177          *      We have finally decided to accept it.
2178          */
2179
2180         neigh_update(neigh, lladdr, NUD_STALE,
2181                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2182                      NEIGH_UPDATE_F_OVERRIDE|
2183                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2184                                      NEIGH_UPDATE_F_ISROUTER))
2185                      );
2186
2187         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2188         if (!nrt)
2189                 goto out;
2190
2191         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2192         if (on_link)
2193                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2194
2195         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2196
2197         if (ip6_ins_rt(nrt))
2198                 goto out;
2199
2200         netevent.old = &rt->dst;
2201         netevent.new = &nrt->dst;
2202         netevent.daddr = &msg->dest;
2203         netevent.neigh = neigh;
2204         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2205
2206         if (rt->rt6i_flags & RTF_CACHE) {
2207                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2208                 ip6_del_rt(rt);
2209         }
2210
2211 out:
2212         neigh_release(neigh);
2213 }
2214
2215 /*
2216  *      Misc support functions
2217  */
2218
2219 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2220 {
2221         BUG_ON(from->dst.from);
2222
2223         rt->rt6i_flags &= ~RTF_EXPIRES;
2224         dst_hold(&from->dst);
2225         rt->dst.from = &from->dst;
2226         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2227 }
2228
2229 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2230 {
2231         rt->dst.input = ort->dst.input;
2232         rt->dst.output = ort->dst.output;
2233         rt->rt6i_dst = ort->rt6i_dst;
2234         rt->dst.error = ort->dst.error;
2235         rt->rt6i_idev = ort->rt6i_idev;
2236         if (rt->rt6i_idev)
2237                 in6_dev_hold(rt->rt6i_idev);
2238         rt->dst.lastuse = jiffies;
2239         rt->rt6i_gateway = ort->rt6i_gateway;
2240         rt->rt6i_flags = ort->rt6i_flags;
2241         rt6_set_from(rt, ort);
2242         rt->rt6i_metric = ort->rt6i_metric;
2243 #ifdef CONFIG_IPV6_SUBTREES
2244         rt->rt6i_src = ort->rt6i_src;
2245 #endif
2246         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2247         rt->rt6i_table = ort->rt6i_table;
2248         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2249 }
2250
2251 #ifdef CONFIG_IPV6_ROUTE_INFO
2252 static struct rt6_info *rt6_get_route_info(struct net *net,
2253                                            const struct in6_addr *prefix, int prefixlen,
2254                                            const struct in6_addr *gwaddr, int ifindex)
2255 {
2256         struct fib6_node *fn;
2257         struct rt6_info *rt = NULL;
2258         struct fib6_table *table;
2259
2260         table = fib6_get_table(net, RT6_TABLE_INFO);
2261         if (!table)
2262                 return NULL;
2263
2264         read_lock_bh(&table->tb6_lock);
2265         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2266         if (!fn)
2267                 goto out;
2268
2269         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2270                 if (rt->dst.dev->ifindex != ifindex)
2271                         continue;
2272                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2273                         continue;
2274                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2275                         continue;
2276                 dst_hold(&rt->dst);
2277                 break;
2278         }
2279 out:
2280         read_unlock_bh(&table->tb6_lock);
2281         return rt;
2282 }
2283
2284 static struct rt6_info *rt6_add_route_info(struct net *net,
2285                                            const struct in6_addr *prefix, int prefixlen,
2286                                            const struct in6_addr *gwaddr, int ifindex,
2287                                            unsigned int pref)
2288 {
2289         struct fib6_config cfg = {
2290                 .fc_table       = RT6_TABLE_INFO,
2291                 .fc_metric      = IP6_RT_PRIO_USER,
2292                 .fc_ifindex     = ifindex,
2293                 .fc_dst_len     = prefixlen,
2294                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2295                                   RTF_UP | RTF_PREF(pref),
2296                 .fc_nlinfo.portid = 0,
2297                 .fc_nlinfo.nlh = NULL,
2298                 .fc_nlinfo.nl_net = net,
2299         };
2300
2301         cfg.fc_dst = *prefix;
2302         cfg.fc_gateway = *gwaddr;
2303
2304         /* We should treat it as a default route if prefix length is 0. */
2305         if (!prefixlen)
2306                 cfg.fc_flags |= RTF_DEFAULT;
2307
2308         ip6_route_add(&cfg);
2309
2310         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2311 }
2312 #endif
2313
2314 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2315 {
2316         struct rt6_info *rt;
2317         struct fib6_table *table;
2318
2319         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2320         if (!table)
2321                 return NULL;
2322
2323         read_lock_bh(&table->tb6_lock);
2324         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2325                 if (dev == rt->dst.dev &&
2326                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2327                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2328                         break;
2329         }
2330         if (rt)
2331                 dst_hold(&rt->dst);
2332         read_unlock_bh(&table->tb6_lock);
2333         return rt;
2334 }
2335
2336 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2337                                      struct net_device *dev,
2338                                      unsigned int pref)
2339 {
2340         struct fib6_config cfg = {
2341                 .fc_table       = RT6_TABLE_DFLT,
2342                 .fc_metric      = IP6_RT_PRIO_USER,
2343                 .fc_ifindex     = dev->ifindex,
2344                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2345                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2346                 .fc_nlinfo.portid = 0,
2347                 .fc_nlinfo.nlh = NULL,
2348                 .fc_nlinfo.nl_net = dev_net(dev),
2349         };
2350
2351         cfg.fc_gateway = *gwaddr;
2352
2353         ip6_route_add(&cfg);
2354
2355         return rt6_get_dflt_router(gwaddr, dev);
2356 }
2357
2358 void rt6_purge_dflt_routers(struct net *net)
2359 {
2360         struct rt6_info *rt;
2361         struct fib6_table *table;
2362
2363         /* NOTE: Keep consistent with rt6_get_dflt_router */
2364         table = fib6_get_table(net, RT6_TABLE_DFLT);
2365         if (!table)
2366                 return;
2367
2368 restart:
2369         read_lock_bh(&table->tb6_lock);
2370         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2371                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2372                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2373                         dst_hold(&rt->dst);
2374                         read_unlock_bh(&table->tb6_lock);
2375                         ip6_del_rt(rt);
2376                         goto restart;
2377                 }
2378         }
2379         read_unlock_bh(&table->tb6_lock);
2380 }
2381
2382 static void rtmsg_to_fib6_config(struct net *net,
2383                                  struct in6_rtmsg *rtmsg,
2384                                  struct fib6_config *cfg)
2385 {
2386         memset(cfg, 0, sizeof(*cfg));
2387
2388         cfg->fc_table = RT6_TABLE_MAIN;
2389         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2390         cfg->fc_metric = rtmsg->rtmsg_metric;
2391         cfg->fc_expires = rtmsg->rtmsg_info;
2392         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2393         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2394         cfg->fc_flags = rtmsg->rtmsg_flags;
2395
2396         cfg->fc_nlinfo.nl_net = net;
2397
2398         cfg->fc_dst = rtmsg->rtmsg_dst;
2399         cfg->fc_src = rtmsg->rtmsg_src;
2400         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2401 }
2402
2403 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2404 {
2405         struct fib6_config cfg;
2406         struct in6_rtmsg rtmsg;
2407         int err;
2408
2409         switch (cmd) {
2410         case SIOCADDRT:         /* Add a route */
2411         case SIOCDELRT:         /* Delete a route */
2412                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2413                         return -EPERM;
2414                 err = copy_from_user(&rtmsg, arg,
2415                                      sizeof(struct in6_rtmsg));
2416                 if (err)
2417                         return -EFAULT;
2418
2419                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2420
2421                 rtnl_lock();
2422                 switch (cmd) {
2423                 case SIOCADDRT:
2424                         err = ip6_route_add(&cfg);
2425                         break;
2426                 case SIOCDELRT:
2427                         err = ip6_route_del(&cfg);
2428                         break;
2429                 default:
2430                         err = -EINVAL;
2431                 }
2432                 rtnl_unlock();
2433
2434                 return err;
2435         }
2436
2437         return -EINVAL;
2438 }
2439
2440 /*
2441  *      Drop the packet on the floor
2442  */
2443
2444 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2445 {
2446         int type;
2447         struct dst_entry *dst = skb_dst(skb);
2448         switch (ipstats_mib_noroutes) {
2449         case IPSTATS_MIB_INNOROUTES:
2450                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2451                 if (type == IPV6_ADDR_ANY) {
2452                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2453                                       IPSTATS_MIB_INADDRERRORS);
2454                         break;
2455                 }
2456                 /* FALLTHROUGH */
2457         case IPSTATS_MIB_OUTNOROUTES:
2458                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2459                               ipstats_mib_noroutes);
2460                 break;
2461         }
2462         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2463         kfree_skb(skb);
2464         return 0;
2465 }
2466
2467 static int ip6_pkt_discard(struct sk_buff *skb)
2468 {
2469         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2470 }
2471
2472 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2473 {
2474         skb->dev = skb_dst(skb)->dev;
2475         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2476 }
2477
2478 static int ip6_pkt_prohibit(struct sk_buff *skb)
2479 {
2480         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2481 }
2482
2483 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2484 {
2485         skb->dev = skb_dst(skb)->dev;
2486         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2487 }
2488
2489 /*
2490  *      Allocate a dst for local (unicast / anycast) address.
2491  */
2492
2493 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2494                                     const struct in6_addr *addr,
2495                                     bool anycast)
2496 {
2497         struct net *net = dev_net(idev->dev);
2498         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2499                                             DST_NOCOUNT);
2500         if (!rt)
2501                 return ERR_PTR(-ENOMEM);
2502
2503         in6_dev_hold(idev);
2504
2505         rt->dst.flags |= DST_HOST;
2506         rt->dst.input = ip6_input;
2507         rt->dst.output = ip6_output;
2508         rt->rt6i_idev = idev;
2509
2510         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2511         if (anycast)
2512                 rt->rt6i_flags |= RTF_ANYCAST;
2513         else
2514                 rt->rt6i_flags |= RTF_LOCAL;
2515
2516         rt->rt6i_gateway  = *addr;
2517         rt->rt6i_dst.addr = *addr;
2518         rt->rt6i_dst.plen = 128;
2519         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2520         rt->dst.flags |= DST_NOCACHE;
2521
2522         atomic_set(&rt->dst.__refcnt, 1);
2523
2524         return rt;
2525 }
2526
2527 int ip6_route_get_saddr(struct net *net,
2528                         struct rt6_info *rt,
2529                         const struct in6_addr *daddr,
2530                         unsigned int prefs,
2531                         struct in6_addr *saddr)
2532 {
2533         struct inet6_dev *idev =
2534                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2535         int err = 0;
2536         if (rt && rt->rt6i_prefsrc.plen)
2537                 *saddr = rt->rt6i_prefsrc.addr;
2538         else
2539                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2540                                          daddr, prefs, saddr);
2541         return err;
2542 }
2543
2544 /* remove deleted ip from prefsrc entries */
2545 struct arg_dev_net_ip {
2546         struct net_device *dev;
2547         struct net *net;
2548         struct in6_addr *addr;
2549 };
2550
2551 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2552 {
2553         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2554         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2555         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2556
2557         if (((void *)rt->dst.dev == dev || !dev) &&
2558             rt != net->ipv6.ip6_null_entry &&
2559             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2560                 /* remove prefsrc entry */
2561                 rt->rt6i_prefsrc.plen = 0;
2562         }
2563         return 0;
2564 }
2565
2566 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2567 {
2568         struct net *net = dev_net(ifp->idev->dev);
2569         struct arg_dev_net_ip adni = {
2570                 .dev = ifp->idev->dev,
2571                 .net = net,
2572                 .addr = &ifp->addr,
2573         };
2574         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2575 }
2576
2577 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2578 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2579
2580 /* Remove routers and update dst entries when gateway turn into host. */
2581 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2582 {
2583         struct in6_addr *gateway = (struct in6_addr *)arg;
2584
2585         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2586              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2587              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2588                 return -1;
2589         }
2590         return 0;
2591 }
2592
2593 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2594 {
2595         fib6_clean_all(net, fib6_clean_tohost, gateway);
2596 }
2597
2598 struct arg_dev_net {
2599         struct net_device *dev;
2600         struct net *net;
2601 };
2602
2603 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2604 {
2605         const struct arg_dev_net *adn = arg;
2606         const struct net_device *dev = adn->dev;
2607
2608         if ((rt->dst.dev == dev || !dev) &&
2609             rt != adn->net->ipv6.ip6_null_entry)
2610                 return -1;
2611
2612         return 0;
2613 }
2614
2615 void rt6_ifdown(struct net *net, struct net_device *dev)
2616 {
2617         struct arg_dev_net adn = {
2618                 .dev = dev,
2619                 .net = net,
2620         };
2621
2622         fib6_clean_all(net, fib6_ifdown, &adn);
2623         icmp6_clean_all(fib6_ifdown, &adn);
2624         if (dev)
2625                 rt6_uncached_list_flush_dev(net, dev);
2626 }
2627
2628 struct rt6_mtu_change_arg {
2629         struct net_device *dev;
2630         unsigned int mtu;
2631 };
2632
2633 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2634 {
2635         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2636         struct inet6_dev *idev;
2637
2638         /* In IPv6 pmtu discovery is not optional,
2639            so that RTAX_MTU lock cannot disable it.
2640            We still use this lock to block changes
2641            caused by addrconf/ndisc.
2642         */
2643
2644         idev = __in6_dev_get(arg->dev);
2645         if (!idev)
2646                 return 0;
2647
2648         /* For administrative MTU increase, there is no way to discover
2649            IPv6 PMTU increase, so PMTU increase should be updated here.
2650            Since RFC 1981 doesn't include administrative MTU increase
2651            update PMTU increase is a MUST. (i.e. jumbo frame)
2652          */
2653         /*
2654            If new MTU is less than route PMTU, this new MTU will be the
2655            lowest MTU in the path, update the route PMTU to reflect PMTU
2656            decreases; if new MTU is greater than route PMTU, and the
2657            old MTU is the lowest MTU in the path, update the route PMTU
2658            to reflect the increase. In this case if the other nodes' MTU
2659            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2660            PMTU discouvery.
2661          */
2662         if (rt->dst.dev == arg->dev &&
2663             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2664                 if (rt->rt6i_flags & RTF_CACHE) {
2665                         /* For RTF_CACHE with rt6i_pmtu == 0
2666                          * (i.e. a redirected route),
2667                          * the metrics of its rt->dst.from has already
2668                          * been updated.
2669                          */
2670                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2671                                 rt->rt6i_pmtu = arg->mtu;
2672                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2673                            (dst_mtu(&rt->dst) < arg->mtu &&
2674                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2675                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2676                 }
2677         }
2678         return 0;
2679 }
2680
2681 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2682 {
2683         struct rt6_mtu_change_arg arg = {
2684                 .dev = dev,
2685                 .mtu = mtu,
2686         };
2687
2688         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2689 }
2690
2691 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2692         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2693         [RTA_OIF]               = { .type = NLA_U32 },
2694         [RTA_IIF]               = { .type = NLA_U32 },
2695         [RTA_PRIORITY]          = { .type = NLA_U32 },
2696         [RTA_METRICS]           = { .type = NLA_NESTED },
2697         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2698         [RTA_PREF]              = { .type = NLA_U8 },
2699         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2700         [RTA_ENCAP]             = { .type = NLA_NESTED },
2701 };
2702
2703 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2704                               struct fib6_config *cfg)
2705 {
2706         struct rtmsg *rtm;
2707         struct nlattr *tb[RTA_MAX+1];
2708         unsigned int pref;
2709         int err;
2710
2711         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2712         if (err < 0)
2713                 goto errout;
2714
2715         err = -EINVAL;
2716         rtm = nlmsg_data(nlh);
2717         memset(cfg, 0, sizeof(*cfg));
2718
2719         cfg->fc_table = rtm->rtm_table;
2720         cfg->fc_dst_len = rtm->rtm_dst_len;
2721         cfg->fc_src_len = rtm->rtm_src_len;
2722         cfg->fc_flags = RTF_UP;
2723         cfg->fc_protocol = rtm->rtm_protocol;
2724         cfg->fc_type = rtm->rtm_type;
2725
2726         if (rtm->rtm_type == RTN_UNREACHABLE ||
2727             rtm->rtm_type == RTN_BLACKHOLE ||
2728             rtm->rtm_type == RTN_PROHIBIT ||
2729             rtm->rtm_type == RTN_THROW)
2730                 cfg->fc_flags |= RTF_REJECT;
2731
2732         if (rtm->rtm_type == RTN_LOCAL)
2733                 cfg->fc_flags |= RTF_LOCAL;
2734
2735         if (rtm->rtm_flags & RTM_F_CLONED)
2736                 cfg->fc_flags |= RTF_CACHE;
2737
2738         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2739         cfg->fc_nlinfo.nlh = nlh;
2740         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2741
2742         if (tb[RTA_GATEWAY]) {
2743                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2744                 cfg->fc_flags |= RTF_GATEWAY;
2745         }
2746
2747         if (tb[RTA_DST]) {
2748                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2749
2750                 if (nla_len(tb[RTA_DST]) < plen)
2751                         goto errout;
2752
2753                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2754         }
2755
2756         if (tb[RTA_SRC]) {
2757                 int plen = (rtm->rtm_src_len + 7) >> 3;
2758
2759                 if (nla_len(tb[RTA_SRC]) < plen)
2760                         goto errout;
2761
2762                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2763         }
2764
2765         if (tb[RTA_PREFSRC])
2766                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2767
2768         if (tb[RTA_OIF])
2769                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2770
2771         if (tb[RTA_PRIORITY])
2772                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2773
2774         if (tb[RTA_METRICS]) {
2775                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2776                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2777         }
2778
2779         if (tb[RTA_TABLE])
2780                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2781
2782         if (tb[RTA_MULTIPATH]) {
2783                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2784                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2785         }
2786
2787         if (tb[RTA_PREF]) {
2788                 pref = nla_get_u8(tb[RTA_PREF]);
2789                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2790                     pref != ICMPV6_ROUTER_PREF_HIGH)
2791                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2792                 cfg->fc_flags |= RTF_PREF(pref);
2793         }
2794
2795         if (tb[RTA_ENCAP])
2796                 cfg->fc_encap = tb[RTA_ENCAP];
2797
2798         if (tb[RTA_ENCAP_TYPE])
2799                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2800
2801         err = 0;
2802 errout:
2803         return err;
2804 }
2805
2806 struct rt6_nh {
2807         struct rt6_info *rt6_info;
2808         struct fib6_config r_cfg;
2809         struct mx6_config mxc;
2810         struct list_head next;
2811 };
2812
2813 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2814 {
2815         struct rt6_nh *nh;
2816
2817         list_for_each_entry(nh, rt6_nh_list, next) {
2818                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2819                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2820                         nh->r_cfg.fc_ifindex);
2821         }
2822 }
2823
2824 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2825                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2826 {
2827         struct rt6_nh *nh;
2828         struct rt6_info *rtnh;
2829         int err = -EEXIST;
2830
2831         list_for_each_entry(nh, rt6_nh_list, next) {
2832                 /* check if rt6_info already exists */
2833                 rtnh = nh->rt6_info;
2834
2835                 if (rtnh->dst.dev == rt->dst.dev &&
2836                     rtnh->rt6i_idev == rt->rt6i_idev &&
2837                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2838                                     &rt->rt6i_gateway))
2839                         return err;
2840         }
2841
2842         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2843         if (!nh)
2844                 return -ENOMEM;
2845         nh->rt6_info = rt;
2846         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2847         if (err) {
2848                 kfree(nh);
2849                 return err;
2850         }
2851         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2852         list_add_tail(&nh->next, rt6_nh_list);
2853
2854         return 0;
2855 }
2856
2857 static int ip6_route_multipath_add(struct fib6_config *cfg)
2858 {
2859         struct fib6_config r_cfg;
2860         struct rtnexthop *rtnh;
2861         struct rt6_info *rt;
2862         struct rt6_nh *err_nh;
2863         struct rt6_nh *nh, *nh_safe;
2864         int remaining;
2865         int attrlen;
2866         int err = 1;
2867         int nhn = 0;
2868         int replace = (cfg->fc_nlinfo.nlh &&
2869                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2870         LIST_HEAD(rt6_nh_list);
2871
2872         remaining = cfg->fc_mp_len;
2873         rtnh = (struct rtnexthop *)cfg->fc_mp;
2874
2875         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2876          * rt6_info structs per nexthop
2877          */
2878         while (rtnh_ok(rtnh, remaining)) {
2879                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2880                 if (rtnh->rtnh_ifindex)
2881                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2882
2883                 attrlen = rtnh_attrlen(rtnh);
2884                 if (attrlen > 0) {
2885                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2886
2887                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2888                         if (nla) {
2889                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2890                                 r_cfg.fc_flags |= RTF_GATEWAY;
2891                         }
2892                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2893                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2894                         if (nla)
2895                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2896                 }
2897
2898                 err = ip6_route_info_create(&r_cfg, &rt);
2899                 if (err)
2900                         goto cleanup;
2901
2902                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2903                 if (err) {
2904                         dst_free(&rt->dst);
2905                         goto cleanup;
2906                 }
2907
2908                 rtnh = rtnh_next(rtnh, &remaining);
2909         }
2910
2911         err_nh = NULL;
2912         list_for_each_entry(nh, &rt6_nh_list, next) {
2913                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2914                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2915                 nh->rt6_info = NULL;
2916                 if (err) {
2917                         if (replace && nhn)
2918                                 ip6_print_replace_route_err(&rt6_nh_list);
2919                         err_nh = nh;
2920                         goto add_errout;
2921                 }
2922
2923                 /* Because each route is added like a single route we remove
2924                  * these flags after the first nexthop: if there is a collision,
2925                  * we have already failed to add the first nexthop:
2926                  * fib6_add_rt2node() has rejected it; when replacing, old
2927                  * nexthops have been replaced by first new, the rest should
2928                  * be added to it.
2929                  */
2930                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2931                                                      NLM_F_REPLACE);
2932                 nhn++;
2933         }
2934
2935         goto cleanup;
2936
2937 add_errout:
2938         /* Delete routes that were already added */
2939         list_for_each_entry(nh, &rt6_nh_list, next) {
2940                 if (err_nh == nh)
2941                         break;
2942                 ip6_route_del(&nh->r_cfg);
2943         }
2944
2945 cleanup:
2946         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2947                 if (nh->rt6_info)
2948                         dst_free(&nh->rt6_info->dst);
2949                 kfree(nh->mxc.mx);
2950                 list_del(&nh->next);
2951                 kfree(nh);
2952         }
2953
2954         return err;
2955 }
2956
2957 static int ip6_route_multipath_del(struct fib6_config *cfg)
2958 {
2959         struct fib6_config r_cfg;
2960         struct rtnexthop *rtnh;
2961         int remaining;
2962         int attrlen;
2963         int err = 1, last_err = 0;
2964
2965         remaining = cfg->fc_mp_len;
2966         rtnh = (struct rtnexthop *)cfg->fc_mp;
2967
2968         /* Parse a Multipath Entry */
2969         while (rtnh_ok(rtnh, remaining)) {
2970                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2971                 if (rtnh->rtnh_ifindex)
2972                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2973
2974                 attrlen = rtnh_attrlen(rtnh);
2975                 if (attrlen > 0) {
2976                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2977
2978                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2979                         if (nla) {
2980                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2981                                 r_cfg.fc_flags |= RTF_GATEWAY;
2982                         }
2983                 }
2984                 err = ip6_route_del(&r_cfg);
2985                 if (err)
2986                         last_err = err;
2987
2988                 rtnh = rtnh_next(rtnh, &remaining);
2989         }
2990
2991         return last_err;
2992 }
2993
2994 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2995 {
2996         struct fib6_config cfg;
2997         int err;
2998
2999         err = rtm_to_fib6_config(skb, nlh, &cfg);
3000         if (err < 0)
3001                 return err;
3002
3003         if (cfg.fc_mp)
3004                 return ip6_route_multipath_del(&cfg);
3005         else
3006                 return ip6_route_del(&cfg);
3007 }
3008
3009 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3010 {
3011         struct fib6_config cfg;
3012         int err;
3013
3014         err = rtm_to_fib6_config(skb, nlh, &cfg);
3015         if (err < 0)
3016                 return err;
3017
3018         if (cfg.fc_mp)
3019                 return ip6_route_multipath_add(&cfg);
3020         else
3021                 return ip6_route_add(&cfg);
3022 }
3023
3024 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3025 {
3026         return NLMSG_ALIGN(sizeof(struct rtmsg))
3027                + nla_total_size(16) /* RTA_SRC */
3028                + nla_total_size(16) /* RTA_DST */
3029                + nla_total_size(16) /* RTA_GATEWAY */
3030                + nla_total_size(16) /* RTA_PREFSRC */
3031                + nla_total_size(4) /* RTA_TABLE */
3032                + nla_total_size(4) /* RTA_IIF */
3033                + nla_total_size(4) /* RTA_OIF */
3034                + nla_total_size(4) /* RTA_PRIORITY */
3035                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3036                + nla_total_size(sizeof(struct rta_cacheinfo))
3037                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3038                + nla_total_size(1) /* RTA_PREF */
3039                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3040 }
3041
3042 static int rt6_fill_node(struct net *net,
3043                          struct sk_buff *skb, struct rt6_info *rt,
3044                          struct in6_addr *dst, struct in6_addr *src,
3045                          int iif, int type, u32 portid, u32 seq,
3046                          int prefix, int nowait, unsigned int flags)
3047 {
3048         u32 metrics[RTAX_MAX];
3049         struct rtmsg *rtm;
3050         struct nlmsghdr *nlh;
3051         long expires;
3052         u32 table;
3053
3054         if (prefix) {   /* user wants prefix routes only */
3055                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3056                         /* success since this is not a prefix route */
3057                         return 1;
3058                 }
3059         }
3060
3061         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3062         if (!nlh)
3063                 return -EMSGSIZE;
3064
3065         rtm = nlmsg_data(nlh);
3066         rtm->rtm_family = AF_INET6;
3067         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3068         rtm->rtm_src_len = rt->rt6i_src.plen;
3069         rtm->rtm_tos = 0;
3070         if (rt->rt6i_table)
3071                 table = rt->rt6i_table->tb6_id;
3072         else
3073                 table = RT6_TABLE_UNSPEC;
3074         rtm->rtm_table = table;
3075         if (nla_put_u32(skb, RTA_TABLE, table))
3076                 goto nla_put_failure;
3077         if (rt->rt6i_flags & RTF_REJECT) {
3078                 switch (rt->dst.error) {
3079                 case -EINVAL:
3080                         rtm->rtm_type = RTN_BLACKHOLE;
3081                         break;
3082                 case -EACCES:
3083                         rtm->rtm_type = RTN_PROHIBIT;
3084                         break;
3085                 case -EAGAIN:
3086                         rtm->rtm_type = RTN_THROW;
3087                         break;
3088                 default:
3089                         rtm->rtm_type = RTN_UNREACHABLE;
3090                         break;
3091                 }
3092         }
3093         else if (rt->rt6i_flags & RTF_LOCAL)
3094                 rtm->rtm_type = RTN_LOCAL;
3095         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3096                 rtm->rtm_type = RTN_LOCAL;
3097         else
3098                 rtm->rtm_type = RTN_UNICAST;
3099         rtm->rtm_flags = 0;
3100         if (!netif_carrier_ok(rt->dst.dev)) {
3101                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3102                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3103                         rtm->rtm_flags |= RTNH_F_DEAD;
3104         }
3105         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3106         rtm->rtm_protocol = rt->rt6i_protocol;
3107         if (rt->rt6i_flags & RTF_DYNAMIC)
3108                 rtm->rtm_protocol = RTPROT_REDIRECT;
3109         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3110                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3111                         rtm->rtm_protocol = RTPROT_RA;
3112                 else
3113                         rtm->rtm_protocol = RTPROT_KERNEL;
3114         }
3115
3116         if (rt->rt6i_flags & RTF_CACHE)
3117                 rtm->rtm_flags |= RTM_F_CLONED;
3118
3119         if (dst) {
3120                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3121                         goto nla_put_failure;
3122                 rtm->rtm_dst_len = 128;
3123         } else if (rtm->rtm_dst_len)
3124                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3125                         goto nla_put_failure;
3126 #ifdef CONFIG_IPV6_SUBTREES
3127         if (src) {
3128                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3129                         goto nla_put_failure;
3130                 rtm->rtm_src_len = 128;
3131         } else if (rtm->rtm_src_len &&
3132                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3133                 goto nla_put_failure;
3134 #endif
3135         if (iif) {
3136 #ifdef CONFIG_IPV6_MROUTE
3137                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3138                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3139                         if (err <= 0) {
3140                                 if (!nowait) {
3141                                         if (err == 0)
3142                                                 return 0;
3143                                         goto nla_put_failure;
3144                                 } else {
3145                                         if (err == -EMSGSIZE)
3146                                                 goto nla_put_failure;
3147                                 }
3148                         }
3149                 } else
3150 #endif
3151                         if (nla_put_u32(skb, RTA_IIF, iif))
3152                                 goto nla_put_failure;
3153         } else if (dst) {
3154                 struct in6_addr saddr_buf;
3155                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3156                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3157                         goto nla_put_failure;
3158         }
3159
3160         if (rt->rt6i_prefsrc.plen) {
3161                 struct in6_addr saddr_buf;
3162                 saddr_buf = rt->rt6i_prefsrc.addr;
3163                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3164                         goto nla_put_failure;
3165         }
3166
3167         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3168         if (rt->rt6i_pmtu)
3169                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3170         if (rtnetlink_put_metrics(skb, metrics) < 0)
3171                 goto nla_put_failure;
3172
3173         if (rt->rt6i_flags & RTF_GATEWAY) {
3174                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3175                         goto nla_put_failure;
3176         }
3177
3178         if (rt->dst.dev &&
3179             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3180                 goto nla_put_failure;
3181         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3182                 goto nla_put_failure;
3183
3184         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3185
3186         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3187                 goto nla_put_failure;
3188
3189         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3190                 goto nla_put_failure;
3191
3192         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3193
3194         nlmsg_end(skb, nlh);
3195         return 0;
3196
3197 nla_put_failure:
3198         nlmsg_cancel(skb, nlh);
3199         return -EMSGSIZE;
3200 }
3201
3202 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3203 {
3204         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3205         int prefix;
3206
3207         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3208                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3209                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3210         } else
3211                 prefix = 0;
3212
3213         return rt6_fill_node(arg->net,
3214                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3215                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3216                      prefix, 0, NLM_F_MULTI);
3217 }
3218
3219 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3220 {
3221         struct net *net = sock_net(in_skb->sk);
3222         struct nlattr *tb[RTA_MAX+1];
3223         struct rt6_info *rt;
3224         struct sk_buff *skb;
3225         struct rtmsg *rtm;
3226         struct flowi6 fl6;
3227         int err, iif = 0, oif = 0;
3228
3229         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3230         if (err < 0)
3231                 goto errout;
3232
3233         err = -EINVAL;
3234         memset(&fl6, 0, sizeof(fl6));
3235
3236         if (tb[RTA_SRC]) {
3237                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3238                         goto errout;
3239
3240                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3241         }
3242
3243         if (tb[RTA_DST]) {
3244                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3245                         goto errout;
3246
3247                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3248         }
3249
3250         if (tb[RTA_IIF])
3251                 iif = nla_get_u32(tb[RTA_IIF]);
3252
3253         if (tb[RTA_OIF])
3254                 oif = nla_get_u32(tb[RTA_OIF]);
3255
3256         if (tb[RTA_MARK])
3257                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3258
3259         if (iif) {
3260                 struct net_device *dev;
3261                 int flags = 0;
3262
3263                 dev = __dev_get_by_index(net, iif);
3264                 if (!dev) {
3265                         err = -ENODEV;
3266                         goto errout;
3267                 }
3268
3269                 fl6.flowi6_iif = iif;
3270
3271                 if (!ipv6_addr_any(&fl6.saddr))
3272                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3273
3274                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3275                                                                flags);
3276         } else {
3277                 fl6.flowi6_oif = oif;
3278
3279                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3280         }
3281
3282         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3283         if (!skb) {
3284                 ip6_rt_put(rt);
3285                 err = -ENOBUFS;
3286                 goto errout;
3287         }
3288
3289         /* Reserve room for dummy headers, this skb can pass
3290            through good chunk of routing engine.
3291          */
3292         skb_reset_mac_header(skb);
3293         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3294
3295         skb_dst_set(skb, &rt->dst);
3296
3297         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3298                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3299                             nlh->nlmsg_seq, 0, 0, 0);
3300         if (err < 0) {
3301                 kfree_skb(skb);
3302                 goto errout;
3303         }
3304
3305         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3306 errout:
3307         return err;
3308 }
3309
3310 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3311                      unsigned int nlm_flags)
3312 {
3313         struct sk_buff *skb;
3314         struct net *net = info->nl_net;
3315         u32 seq;
3316         int err;
3317
3318         err = -ENOBUFS;
3319         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3320
3321         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3322         if (!skb)
3323                 goto errout;
3324
3325         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3326                                 event, info->portid, seq, 0, 0, nlm_flags);
3327         if (err < 0) {
3328                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3329                 WARN_ON(err == -EMSGSIZE);
3330                 kfree_skb(skb);
3331                 goto errout;
3332         }
3333         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3334                     info->nlh, gfp_any());
3335         return;
3336 errout:
3337         if (err < 0)
3338                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3339 }
3340
3341 static int ip6_route_dev_notify(struct notifier_block *this,
3342                                 unsigned long event, void *ptr)
3343 {
3344         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3345         struct net *net = dev_net(dev);
3346
3347         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3348                 net->ipv6.ip6_null_entry->dst.dev = dev;
3349                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3350 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3351                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3352                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3353                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3354                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3355 #endif
3356         }
3357
3358         return NOTIFY_OK;
3359 }
3360
3361 /*
3362  *      /proc
3363  */
3364
3365 #ifdef CONFIG_PROC_FS
3366
3367 static const struct file_operations ipv6_route_proc_fops = {
3368         .owner          = THIS_MODULE,
3369         .open           = ipv6_route_open,
3370         .read           = seq_read,
3371         .llseek         = seq_lseek,
3372         .release        = seq_release_net,
3373 };
3374
3375 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3376 {
3377         struct net *net = (struct net *)seq->private;
3378         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3379                    net->ipv6.rt6_stats->fib_nodes,
3380                    net->ipv6.rt6_stats->fib_route_nodes,
3381                    net->ipv6.rt6_stats->fib_rt_alloc,
3382                    net->ipv6.rt6_stats->fib_rt_entries,
3383                    net->ipv6.rt6_stats->fib_rt_cache,
3384                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3385                    net->ipv6.rt6_stats->fib_discarded_routes);
3386
3387         return 0;
3388 }
3389
3390 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3391 {
3392         return single_open_net(inode, file, rt6_stats_seq_show);
3393 }
3394
3395 static const struct file_operations rt6_stats_seq_fops = {
3396         .owner   = THIS_MODULE,
3397         .open    = rt6_stats_seq_open,
3398         .read    = seq_read,
3399         .llseek  = seq_lseek,
3400         .release = single_release_net,
3401 };
3402 #endif  /* CONFIG_PROC_FS */
3403
3404 #ifdef CONFIG_SYSCTL
3405
3406 static
3407 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3408                               void __user *buffer, size_t *lenp, loff_t *ppos)
3409 {
3410         struct net *net;
3411         int delay;
3412         if (!write)
3413                 return -EINVAL;
3414
3415         net = (struct net *)ctl->extra1;
3416         delay = net->ipv6.sysctl.flush_delay;
3417         proc_dointvec(ctl, write, buffer, lenp, ppos);
3418         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3419         return 0;
3420 }
3421
3422 struct ctl_table ipv6_route_table_template[] = {
3423         {
3424                 .procname       =       "flush",
3425                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3426                 .maxlen         =       sizeof(int),
3427                 .mode           =       0200,
3428                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3429         },
3430         {
3431                 .procname       =       "gc_thresh",
3432                 .data           =       &ip6_dst_ops_template.gc_thresh,
3433                 .maxlen         =       sizeof(int),
3434                 .mode           =       0644,
3435                 .proc_handler   =       proc_dointvec,
3436         },
3437         {
3438                 .procname       =       "max_size",
3439                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3440                 .maxlen         =       sizeof(int),
3441                 .mode           =       0644,
3442                 .proc_handler   =       proc_dointvec,
3443         },
3444         {
3445                 .procname       =       "gc_min_interval",
3446                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3447                 .maxlen         =       sizeof(int),
3448                 .mode           =       0644,
3449                 .proc_handler   =       proc_dointvec_jiffies,
3450         },
3451         {
3452                 .procname       =       "gc_timeout",
3453                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3454                 .maxlen         =       sizeof(int),
3455                 .mode           =       0644,
3456                 .proc_handler   =       proc_dointvec_jiffies,
3457         },
3458         {
3459                 .procname       =       "gc_interval",
3460                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3461                 .maxlen         =       sizeof(int),
3462                 .mode           =       0644,
3463                 .proc_handler   =       proc_dointvec_jiffies,
3464         },
3465         {
3466                 .procname       =       "gc_elasticity",
3467                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3468                 .maxlen         =       sizeof(int),
3469                 .mode           =       0644,
3470                 .proc_handler   =       proc_dointvec,
3471         },
3472         {
3473                 .procname       =       "mtu_expires",
3474                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3475                 .maxlen         =       sizeof(int),
3476                 .mode           =       0644,
3477                 .proc_handler   =       proc_dointvec_jiffies,
3478         },
3479         {
3480                 .procname       =       "min_adv_mss",
3481                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3482                 .maxlen         =       sizeof(int),
3483                 .mode           =       0644,
3484                 .proc_handler   =       proc_dointvec,
3485         },
3486         {
3487                 .procname       =       "gc_min_interval_ms",
3488                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3489                 .maxlen         =       sizeof(int),
3490                 .mode           =       0644,
3491                 .proc_handler   =       proc_dointvec_ms_jiffies,
3492         },
3493         { }
3494 };
3495
3496 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3497 {
3498         struct ctl_table *table;
3499
3500         table = kmemdup(ipv6_route_table_template,
3501                         sizeof(ipv6_route_table_template),
3502                         GFP_KERNEL);
3503
3504         if (table) {
3505                 table[0].data = &net->ipv6.sysctl.flush_delay;
3506                 table[0].extra1 = net;
3507                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3508                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3509                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3510                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3511                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3512                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3513                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3514                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3515                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3516
3517                 /* Don't export sysctls to unprivileged users */
3518                 if (net->user_ns != &init_user_ns)
3519                         table[0].procname = NULL;
3520         }
3521
3522         return table;
3523 }
3524 #endif
3525
3526 static int __net_init ip6_route_net_init(struct net *net)
3527 {
3528         int ret = -ENOMEM;
3529
3530         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3531                sizeof(net->ipv6.ip6_dst_ops));
3532
3533         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3534                 goto out_ip6_dst_ops;
3535
3536         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3537                                            sizeof(*net->ipv6.ip6_null_entry),
3538                                            GFP_KERNEL);
3539         if (!net->ipv6.ip6_null_entry)
3540                 goto out_ip6_dst_entries;
3541         net->ipv6.ip6_null_entry->dst.path =
3542                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3543         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3544         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3545                          ip6_template_metrics, true);
3546
3547 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3548         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3549                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3550                                                GFP_KERNEL);
3551         if (!net->ipv6.ip6_prohibit_entry)
3552                 goto out_ip6_null_entry;
3553         net->ipv6.ip6_prohibit_entry->dst.path =
3554                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3555         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3556         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3557                          ip6_template_metrics, true);
3558
3559         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3560                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3561                                                GFP_KERNEL);
3562         if (!net->ipv6.ip6_blk_hole_entry)
3563                 goto out_ip6_prohibit_entry;
3564         net->ipv6.ip6_blk_hole_entry->dst.path =
3565                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3566         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3567         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3568                          ip6_template_metrics, true);
3569 #endif
3570
3571         net->ipv6.sysctl.flush_delay = 0;
3572         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3573         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3574         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3575         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3576         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3577         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3578         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3579
3580         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3581
3582         ret = 0;
3583 out:
3584         return ret;
3585
3586 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3587 out_ip6_prohibit_entry:
3588         kfree(net->ipv6.ip6_prohibit_entry);
3589 out_ip6_null_entry:
3590         kfree(net->ipv6.ip6_null_entry);
3591 #endif
3592 out_ip6_dst_entries:
3593         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3594 out_ip6_dst_ops:
3595         goto out;
3596 }
3597
3598 static void __net_exit ip6_route_net_exit(struct net *net)
3599 {
3600         kfree(net->ipv6.ip6_null_entry);
3601 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3602         kfree(net->ipv6.ip6_prohibit_entry);
3603         kfree(net->ipv6.ip6_blk_hole_entry);
3604 #endif
3605         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3606 }
3607
3608 static int __net_init ip6_route_net_init_late(struct net *net)
3609 {
3610 #ifdef CONFIG_PROC_FS
3611         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3612         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3613 #endif
3614         return 0;
3615 }
3616
3617 static void __net_exit ip6_route_net_exit_late(struct net *net)
3618 {
3619 #ifdef CONFIG_PROC_FS
3620         remove_proc_entry("ipv6_route", net->proc_net);
3621         remove_proc_entry("rt6_stats", net->proc_net);
3622 #endif
3623 }
3624
3625 static struct pernet_operations ip6_route_net_ops = {
3626         .init = ip6_route_net_init,
3627         .exit = ip6_route_net_exit,
3628 };
3629
3630 static int __net_init ipv6_inetpeer_init(struct net *net)
3631 {
3632         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3633
3634         if (!bp)
3635                 return -ENOMEM;
3636         inet_peer_base_init(bp);
3637         net->ipv6.peers = bp;
3638         return 0;
3639 }
3640
3641 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3642 {
3643         struct inet_peer_base *bp = net->ipv6.peers;
3644
3645         net->ipv6.peers = NULL;
3646         inetpeer_invalidate_tree(bp);
3647         kfree(bp);
3648 }
3649
3650 static struct pernet_operations ipv6_inetpeer_ops = {
3651         .init   =       ipv6_inetpeer_init,
3652         .exit   =       ipv6_inetpeer_exit,
3653 };
3654
3655 static struct pernet_operations ip6_route_net_late_ops = {
3656         .init = ip6_route_net_init_late,
3657         .exit = ip6_route_net_exit_late,
3658 };
3659
3660 static struct notifier_block ip6_route_dev_notifier = {
3661         .notifier_call = ip6_route_dev_notify,
3662         .priority = 0,
3663 };
3664
3665 int __init ip6_route_init(void)
3666 {
3667         int ret;
3668         int cpu;
3669
3670         ret = -ENOMEM;
3671         ip6_dst_ops_template.kmem_cachep =
3672                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3673                                   SLAB_HWCACHE_ALIGN, NULL);
3674         if (!ip6_dst_ops_template.kmem_cachep)
3675                 goto out;
3676
3677         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3678         if (ret)
3679                 goto out_kmem_cache;
3680
3681         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3682         if (ret)
3683                 goto out_dst_entries;
3684
3685         ret = register_pernet_subsys(&ip6_route_net_ops);
3686         if (ret)
3687                 goto out_register_inetpeer;
3688
3689         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3690
3691         /* Registering of the loopback is done before this portion of code,
3692          * the loopback reference in rt6_info will not be taken, do it
3693          * manually for init_net */
3694         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3695         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3696   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3697         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3698         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3699         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3700         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3701   #endif
3702         ret = fib6_init();
3703         if (ret)
3704                 goto out_register_subsys;
3705
3706         ret = xfrm6_init();
3707         if (ret)
3708                 goto out_fib6_init;
3709
3710         ret = fib6_rules_init();
3711         if (ret)
3712                 goto xfrm6_init;
3713
3714         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3715         if (ret)
3716                 goto fib6_rules_init;
3717
3718         ret = -ENOBUFS;
3719         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3720             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3721             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3722                 goto out_register_late_subsys;
3723
3724         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3725         if (ret)
3726                 goto out_register_late_subsys;
3727
3728         for_each_possible_cpu(cpu) {
3729                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3730
3731                 INIT_LIST_HEAD(&ul->head);
3732                 spin_lock_init(&ul->lock);
3733         }
3734
3735 out:
3736         return ret;
3737
3738 out_register_late_subsys:
3739         unregister_pernet_subsys(&ip6_route_net_late_ops);
3740 fib6_rules_init:
3741         fib6_rules_cleanup();
3742 xfrm6_init:
3743         xfrm6_fini();
3744 out_fib6_init:
3745         fib6_gc_cleanup();
3746 out_register_subsys:
3747         unregister_pernet_subsys(&ip6_route_net_ops);
3748 out_register_inetpeer:
3749         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3750 out_dst_entries:
3751         dst_entries_destroy(&ip6_dst_blackhole_ops);
3752 out_kmem_cache:
3753         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3754         goto out;
3755 }
3756
3757 void ip6_route_cleanup(void)
3758 {
3759         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3760         unregister_pernet_subsys(&ip6_route_net_late_ops);
3761         fib6_rules_cleanup();
3762         xfrm6_fini();
3763         fib6_gc_cleanup();
3764         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3765         unregister_pernet_subsys(&ip6_route_net_ops);
3766         dst_entries_destroy(&ip6_dst_blackhole_ops);
3767         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3768 }