net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64 #include <net/l3mdev.h>
  65 #include <trace/events/fib6.h>
  66
  67 #include <asm/uaccess.h>
  68
  69 #ifdef CONFIG_SYSCTL
  70 #include <linux/sysctl.h>
  71 #endif
  72
  73 enum rt6_nud_state {
  74         RT6_NUD_FAIL_HARD = -3,
  75         RT6_NUD_FAIL_PROBE = -2,
  76         RT6_NUD_FAIL_DO_RR = -1,
  77         RT6_NUD_SUCCEED = 1
  78 };
  79
  80 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  81 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  82 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  83 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  84 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  85 static void             ip6_dst_destroy(struct dst_entry *);
  86 static void             ip6_dst_ifdown(struct dst_entry *,
  87                                        struct net_device *dev, int how);
  88 static int               ip6_dst_gc(struct dst_ops *ops);
  89
  90 static int              ip6_pkt_discard(struct sk_buff *skb);
  91 static int              ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  92 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  93 static int              ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  94 static void             ip6_link_failure(struct sk_buff *skb);
  95 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  96                                            struct sk_buff *skb, u32 mtu);
  97 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  98                                         struct sk_buff *skb);
  99 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
 100 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
 101
 102 #ifdef CONFIG_IPV6_ROUTE_INFO
 103 static struct rt6_info *rt6_add_route_info(struct net *net,
 104                                            const struct in6_addr *prefix, int prefixlen,
 105                                            const struct in6_addr *gwaddr,
 106                                            struct net_device *dev,
 107                                            unsigned int pref);
 108 static struct rt6_info *rt6_get_route_info(struct net *net,
 109                                            const struct in6_addr *prefix, int prefixlen,
 110                                            const struct in6_addr *gwaddr,
 111                                            struct net_device *dev);
 112 #endif
 113
 114 struct uncached_list {
 115         spinlock_t              lock;
 116         struct list_head        head;
 117 };
 118
 119 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 120
 121 static void rt6_uncached_list_add(struct rt6_info *rt)
 122 {
 123         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 124
 125         rt->dst.flags |= DST_NOCACHE;
 126         rt->rt6i_uncached_list = ul;
 127
 128         spin_lock_bh(&ul->lock);
 129         list_add_tail(&rt->rt6i_uncached, &ul->head);
 130         spin_unlock_bh(&ul->lock);
 131 }
 132
 133 static void rt6_uncached_list_del(struct rt6_info *rt)
 134 {
 135         if (!list_empty(&rt->rt6i_uncached)) {
 136                 struct uncached_list *ul = rt->rt6i_uncached_list;
 137
 138                 spin_lock_bh(&ul->lock);
 139                 list_del(&rt->rt6i_uncached);
 140                 spin_unlock_bh(&ul->lock);
 141         }
 142 }
 143
 144 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 145 {
 146         struct net_device *loopback_dev = net->loopback_dev;
 147         int cpu;
 148
 149         if (dev == loopback_dev)
 150                 return;
 151
 152         for_each_possible_cpu(cpu) {
 153                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 154                 struct rt6_info *rt;
 155
 156                 spin_lock_bh(&ul->lock);
 157                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 158                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 159                         struct net_device *rt_dev = rt->dst.dev;
 160
 161                         if (rt_idev->dev == dev) {
 162                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 163                                 in6_dev_put(rt_idev);
 164                         }
 165
 166                         if (rt_dev == dev) {
 167                                 rt->dst.dev = loopback_dev;
 168                                 dev_hold(rt->dst.dev);
 169                                 dev_put(rt_dev);
 170                         }
 171                 }
 172                 spin_unlock_bh(&ul->lock);
 173         }
 174 }
 175
 176 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 177 {
 178         return dst_metrics_write_ptr(rt->dst.from);
 179 }
 180
 181 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 182 {
 183         struct rt6_info *rt = (struct rt6_info *)dst;
 184
 185         if (rt->rt6i_flags & RTF_PCPU)
 186                 return rt6_pcpu_cow_metrics(rt);
 187         else if (rt->rt6i_flags & RTF_CACHE)
 188                 return NULL;
 189         else
 190                 return dst_cow_metrics_generic(dst, old);
 191 }
 192
 193 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 194                                              struct sk_buff *skb,
 195                                              const void *daddr)
 196 {
 197         struct in6_addr *p = &rt->rt6i_gateway;
 198
 199         if (!ipv6_addr_any(p))
 200                 return (const void *) p;
 201         else if (skb)
 202                 return &ipv6_hdr(skb)->daddr;
 203         return daddr;
 204 }
 205
 206 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 207                                           struct sk_buff *skb,
 208                                           const void *daddr)
 209 {
 210         struct rt6_info *rt = (struct rt6_info *) dst;
 211         struct neighbour *n;
 212
 213         daddr = choose_neigh_daddr(rt, skb, daddr);
 214         n = __ipv6_neigh_lookup(dst->dev, daddr);
 215         if (n)
 216                 return n;
 217         return neigh_create(&nd_tbl, daddr, dst->dev);
 218 }
 219
 220 static struct dst_ops ip6_dst_ops_template = {
 221         .family                 =       AF_INET6,
 222         .gc                     =       ip6_dst_gc,
 223         .gc_thresh              =       1024,
 224         .check                  =       ip6_dst_check,
 225         .default_advmss         =       ip6_default_advmss,
 226         .mtu                    =       ip6_mtu,
 227         .cow_metrics            =       ipv6_cow_metrics,
 228         .destroy                =       ip6_dst_destroy,
 229         .ifdown                 =       ip6_dst_ifdown,
 230         .negative_advice        =       ip6_negative_advice,
 231         .link_failure           =       ip6_link_failure,
 232         .update_pmtu            =       ip6_rt_update_pmtu,
 233         .redirect               =       rt6_do_redirect,
 234         .local_out              =       __ip6_local_out,
 235         .neigh_lookup           =       ip6_neigh_lookup,
 236 };
 237
 238 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 239 {
 240         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 241
 242         return mtu ? : dst->dev->mtu;
 243 }
 244
 245 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 246                                          struct sk_buff *skb, u32 mtu)
 247 {
 248 }
 249
 250 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 251                                       struct sk_buff *skb)
 252 {
 253 }
 254
 255 static struct dst_ops ip6_dst_blackhole_ops = {
 256         .family                 =       AF_INET6,
 257         .destroy                =       ip6_dst_destroy,
 258         .check                  =       ip6_dst_check,
 259         .mtu                    =       ip6_blackhole_mtu,
 260         .default_advmss         =       ip6_default_advmss,
 261         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 262         .redirect               =       ip6_rt_blackhole_redirect,
 263         .cow_metrics            =       dst_cow_metrics_generic,
 264         .neigh_lookup           =       ip6_neigh_lookup,
 265 };
 266
 267 static const u32 ip6_template_metrics[RTAX_MAX] = {
 268         [RTAX_HOPLIMIT - 1] = 0,
 269 };
 270
 271 static const struct rt6_info ip6_null_entry_template = {
 272         .dst = {
 273                 .__refcnt       = ATOMIC_INIT(1),
 274                 .__use          = 1,
 275                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 276                 .error          = -ENETUNREACH,
 277                 .input          = ip6_pkt_discard,
 278                 .output         = ip6_pkt_discard_out,
 279         },
 280         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 281         .rt6i_protocol  = RTPROT_KERNEL,
 282         .rt6i_metric    = ~(u32) 0,
 283         .rt6i_ref       = ATOMIC_INIT(1),
 284 };
 285
 286 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 287
 288 static const struct rt6_info ip6_prohibit_entry_template = {
 289         .dst = {
 290                 .__refcnt       = ATOMIC_INIT(1),
 291                 .__use          = 1,
 292                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 293                 .error          = -EACCES,
 294                 .input          = ip6_pkt_prohibit,
 295                 .output         = ip6_pkt_prohibit_out,
 296         },
 297         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 298         .rt6i_protocol  = RTPROT_KERNEL,
 299         .rt6i_metric    = ~(u32) 0,
 300         .rt6i_ref       = ATOMIC_INIT(1),
 301 };
 302
 303 static const struct rt6_info ip6_blk_hole_entry_template = {
 304         .dst = {
 305                 .__refcnt       = ATOMIC_INIT(1),
 306                 .__use          = 1,
 307                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 308                 .error          = -EINVAL,
 309                 .input          = dst_discard,
 310                 .output         = dst_discard_out,
 311         },
 312         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 313         .rt6i_protocol  = RTPROT_KERNEL,
 314         .rt6i_metric    = ~(u32) 0,
 315         .rt6i_ref       = ATOMIC_INIT(1),
 316 };
 317
 318 #endif
 319
 320 static void rt6_info_init(struct rt6_info *rt)
 321 {
 322         struct dst_entry *dst = &rt->dst;
 323
 324         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 325         INIT_LIST_HEAD(&rt->rt6i_siblings);
 326         INIT_LIST_HEAD(&rt->rt6i_uncached);
 327 }
 328
 329 /* allocate dst with ip6_dst_ops */
 330 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 331                                         struct net_device *dev,
 332                                         int flags)
 333 {
 334         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 335                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 336
 337         if (rt)
 338                 rt6_info_init(rt);
 339
 340         return rt;
 341 }
 342
 343 struct rt6_info *ip6_dst_alloc(struct net *net,
 344                                struct net_device *dev,
 345                                int flags)
 346 {
 347         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 348
 349         if (rt) {
 350                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 351                 if (rt->rt6i_pcpu) {
 352                         int cpu;
 353
 354                         for_each_possible_cpu(cpu) {
 355                                 struct rt6_info **p;
 356
 357                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 358                                 /* no one shares rt */
 359                                 *p =  NULL;
 360                         }
 361                 } else {
 362                         dst_destroy((struct dst_entry *)rt);
 363                         return NULL;
 364                 }
 365         }
 366
 367         return rt;
 368 }
 369 EXPORT_SYMBOL(ip6_dst_alloc);
 370
 371 static void ip6_dst_destroy(struct dst_entry *dst)
 372 {
 373         struct rt6_info *rt = (struct rt6_info *)dst;
 374         struct dst_entry *from = dst->from;
 375         struct inet6_dev *idev;
 376
 377         dst_destroy_metrics_generic(dst);
 378         free_percpu(rt->rt6i_pcpu);
 379         rt6_uncached_list_del(rt);
 380
 381         idev = rt->rt6i_idev;
 382         if (idev) {
 383                 rt->rt6i_idev = NULL;
 384                 in6_dev_put(idev);
 385         }
 386
 387         dst->from = NULL;
 388         dst_release(from);
 389 }
 390
 391 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 392                            int how)
 393 {
 394         struct rt6_info *rt = (struct rt6_info *)dst;
 395         struct inet6_dev *idev = rt->rt6i_idev;
 396         struct net_device *loopback_dev =
 397                 dev_net(dev)->loopback_dev;
 398
 399         if (dev != loopback_dev) {
 400                 if (idev && idev->dev == dev) {
 401                         struct inet6_dev *loopback_idev =
 402                                 in6_dev_get(loopback_dev);
 403                         if (loopback_idev) {
 404                                 rt->rt6i_idev = loopback_idev;
 405                                 in6_dev_put(idev);
 406                         }
 407                 }
 408         }
 409 }
 410
 411 static bool __rt6_check_expired(const struct rt6_info *rt)
 412 {
 413         if (rt->rt6i_flags & RTF_EXPIRES)
 414                 return time_after(jiffies, rt->dst.expires);
 415         else
 416                 return false;
 417 }
 418
 419 static bool rt6_check_expired(const struct rt6_info *rt)
 420 {
 421         if (rt->rt6i_flags & RTF_EXPIRES) {
 422                 if (time_after(jiffies, rt->dst.expires))
 423                         return true;
 424         } else if (rt->dst.from) {
 425                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 426         }
 427         return false;
 428 }
 429
 430 /* Multipath route selection:
 431  *   Hash based function using packet header and flowlabel.
 432  * Adapted from fib_info_hashfn()
 433  */
 434 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 435                                const struct flowi6 *fl6)
 436 {
 437         return get_hash_from_flowi6(fl6) % candidate_count;
 438 }
 439
 440 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 441                                              struct flowi6 *fl6, int oif,
 442                                              int strict)
 443 {
 444         struct rt6_info *sibling, *next_sibling;
 445         int route_choosen;
 446
 447         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 448         /* Don't change the route, if route_choosen == 0
 449          * (siblings does not include ourself)
 450          */
 451         if (route_choosen)
 452                 list_for_each_entry_safe(sibling, next_sibling,
 453                                 &match->rt6i_siblings, rt6i_siblings) {
 454                         route_choosen--;
 455                         if (route_choosen == 0) {
 456                                 if (rt6_score_route(sibling, oif, strict) < 0)
 457                                         break;
 458                                 match = sibling;
 459                                 break;
 460                         }
 461                 }
 462         return match;
 463 }
 464
 465 /*
 466  *      Route lookup. Any table->tb6_lock is implied.
 467  */
 468
 469 static inline struct rt6_info *rt6_device_match(struct net *net,
 470                                                     struct rt6_info *rt,
 471                                                     const struct in6_addr *saddr,
 472                                                     int oif,
 473                                                     int flags)
 474 {
 475         struct rt6_info *local = NULL;
 476         struct rt6_info *sprt;
 477
 478         if (!oif && ipv6_addr_any(saddr))
 479                 goto out;
 480
 481         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 482                 struct net_device *dev = sprt->dst.dev;
 483
 484                 if (oif) {
 485                         if (dev->ifindex == oif)
 486                                 return sprt;
 487                         if (dev->flags & IFF_LOOPBACK) {
 488                                 if (!sprt->rt6i_idev ||
 489                                     sprt->rt6i_idev->dev->ifindex != oif) {
 490                                         if (flags & RT6_LOOKUP_F_IFACE)
 491                                                 continue;
 492                                         if (local &&
 493                                             local->rt6i_idev->dev->ifindex == oif)
 494                                                 continue;
 495                                 }
 496                                 local = sprt;
 497                         }
 498                 } else {
 499                         if (ipv6_chk_addr(net, saddr, dev,
 500                                           flags & RT6_LOOKUP_F_IFACE))
 501                                 return sprt;
 502                 }
 503         }
 504
 505         if (oif) {
 506                 if (local)
 507                         return local;
 508
 509                 if (flags & RT6_LOOKUP_F_IFACE)
 510                         return net->ipv6.ip6_null_entry;
 511         }
 512 out:
 513         return rt;
 514 }
 515
 516 #ifdef CONFIG_IPV6_ROUTER_PREF
 517 struct __rt6_probe_work {
 518         struct work_struct work;
 519         struct in6_addr target;
 520         struct net_device *dev;
 521 };
 522
 523 static void rt6_probe_deferred(struct work_struct *w)
 524 {
 525         struct in6_addr mcaddr;
 526         struct __rt6_probe_work *work =
 527                 container_of(w, struct __rt6_probe_work, work);
 528
 529         addrconf_addr_solict_mult(&work->target, &mcaddr);
 530         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
 531         dev_put(work->dev);
 532         kfree(work);
 533 }
 534
 535 static void rt6_probe(struct rt6_info *rt)
 536 {
 537         struct __rt6_probe_work *work;
 538         struct neighbour *neigh;
 539         /*
 540          * Okay, this does not seem to be appropriate
 541          * for now, however, we need to check if it
 542          * is really so; aka Router Reachability Probing.
 543          *
 544          * Router Reachability Probe MUST be rate-limited
 545          * to no more than one per minute.
 546          */
 547         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 548                 return;
 549         rcu_read_lock_bh();
 550         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 551         if (neigh) {
 552                 if (neigh->nud_state & NUD_VALID)
 553                         goto out;
 554
 555                 work = NULL;
 556                 write_lock(&neigh->lock);
 557                 if (!(neigh->nud_state & NUD_VALID) &&
 558                     time_after(jiffies,
 559                                neigh->updated +
 560                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 561                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 562                         if (work)
 563                                 __neigh_set_probe_once(neigh);
 564                 }
 565                 write_unlock(&neigh->lock);
 566         } else {
 567                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 568         }
 569
 570         if (work) {
 571                 INIT_WORK(&work->work, rt6_probe_deferred);
 572                 work->target = rt->rt6i_gateway;
 573                 dev_hold(rt->dst.dev);
 574                 work->dev = rt->dst.dev;
 575                 schedule_work(&work->work);
 576         }
 577
 578 out:
 579         rcu_read_unlock_bh();
 580 }
 581 #else
 582 static inline void rt6_probe(struct rt6_info *rt)
 583 {
 584 }
 585 #endif
 586
 587 /*
 588  * Default Router Selection (RFC 2461 6.3.6)
 589  */
 590 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 591 {
 592         struct net_device *dev = rt->dst.dev;
 593         if (!oif || dev->ifindex == oif)
 594                 return 2;
 595         if ((dev->flags & IFF_LOOPBACK) &&
 596             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 597                 return 1;
 598         return 0;
 599 }
 600
 601 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 602 {
 603         struct neighbour *neigh;
 604         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 605
 606         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 607             !(rt->rt6i_flags & RTF_GATEWAY))
 608                 return RT6_NUD_SUCCEED;
 609
 610         rcu_read_lock_bh();
 611         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 612         if (neigh) {
 613                 read_lock(&neigh->lock);
 614                 if (neigh->nud_state & NUD_VALID)
 615                         ret = RT6_NUD_SUCCEED;
 616 #ifdef CONFIG_IPV6_ROUTER_PREF
 617                 else if (!(neigh->nud_state & NUD_FAILED))
 618                         ret = RT6_NUD_SUCCEED;
 619                 else
 620                         ret = RT6_NUD_FAIL_PROBE;
 621 #endif
 622                 read_unlock(&neigh->lock);
 623         } else {
 624                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 625                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 626         }
 627         rcu_read_unlock_bh();
 628
 629         return ret;
 630 }
 631
 632 static int rt6_score_route(struct rt6_info *rt, int oif,
 633                            int strict)
 634 {
 635         int m;
 636
 637         m = rt6_check_dev(rt, oif);
 638         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 639                 return RT6_NUD_FAIL_HARD;
 640 #ifdef CONFIG_IPV6_ROUTER_PREF
 641         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 642 #endif
 643         if (strict & RT6_LOOKUP_F_REACHABLE) {
 644                 int n = rt6_check_neigh(rt);
 645                 if (n < 0)
 646                         return n;
 647         }
 648         return m;
 649 }
 650
 651 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 652                                    int *mpri, struct rt6_info *match,
 653                                    bool *do_rr)
 654 {
 655         int m;
 656         bool match_do_rr = false;
 657         struct inet6_dev *idev = rt->rt6i_idev;
 658         struct net_device *dev = rt->dst.dev;
 659
 660         if (dev && !netif_carrier_ok(dev) &&
 661             idev->cnf.ignore_routes_with_linkdown &&
 662             !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
 663                 goto out;
 664
 665         if (rt6_check_expired(rt))
 666                 goto out;
 667
 668         m = rt6_score_route(rt, oif, strict);
 669         if (m == RT6_NUD_FAIL_DO_RR) {
 670                 match_do_rr = true;
 671                 m = 0; /* lowest valid score */
 672         } else if (m == RT6_NUD_FAIL_HARD) {
 673                 goto out;
 674         }
 675
 676         if (strict & RT6_LOOKUP_F_REACHABLE)
 677                 rt6_probe(rt);
 678
 679         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 680         if (m > *mpri) {
 681                 *do_rr = match_do_rr;
 682                 *mpri = m;
 683                 match = rt;
 684         }
 685 out:
 686         return match;
 687 }
 688
 689 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 690                                      struct rt6_info *rr_head,
 691                                      u32 metric, int oif, int strict,
 692                                      bool *do_rr)
 693 {
 694         struct rt6_info *rt, *match, *cont;
 695         int mpri = -1;
 696
 697         match = NULL;
 698         cont = NULL;
 699         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 700                 if (rt->rt6i_metric != metric) {
 701                         cont = rt;
 702                         break;
 703                 }
 704
 705                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 706         }
 707
 708         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 709                 if (rt->rt6i_metric != metric) {
 710                         cont = rt;
 711                         break;
 712                 }
 713
 714                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 715         }
 716
 717         if (match || !cont)
 718                 return match;
 719
 720         for (rt = cont; rt; rt = rt->dst.rt6_next)
 721                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 722
 723         return match;
 724 }
 725
 726 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 727 {
 728         struct rt6_info *match, *rt0;
 729         struct net *net;
 730         bool do_rr = false;
 731
 732         rt0 = fn->rr_ptr;
 733         if (!rt0)
 734                 fn->rr_ptr = rt0 = fn->leaf;
 735
 736         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 737                              &do_rr);
 738
 739         if (do_rr) {
 740                 struct rt6_info *next = rt0->dst.rt6_next;
 741
 742                 /* no entries matched; do round-robin */
 743                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 744                         next = fn->leaf;
 745
 746                 if (next != rt0)
 747                         fn->rr_ptr = next;
 748         }
 749
 750         net = dev_net(rt0->dst.dev);
 751         return match ? match : net->ipv6.ip6_null_entry;
 752 }
 753
 754 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 755 {
 756         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 757 }
 758
 759 #ifdef CONFIG_IPV6_ROUTE_INFO
 760 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 761                   const struct in6_addr *gwaddr)
 762 {
 763         struct net *net = dev_net(dev);
 764         struct route_info *rinfo = (struct route_info *) opt;
 765         struct in6_addr prefix_buf, *prefix;
 766         unsigned int pref;
 767         unsigned long lifetime;
 768         struct rt6_info *rt;
 769
 770         if (len < sizeof(struct route_info)) {
 771                 return -EINVAL;
 772         }
 773
 774         /* Sanity check for prefix_len and length */
 775         if (rinfo->length > 3) {
 776                 return -EINVAL;
 777         } else if (rinfo->prefix_len > 128) {
 778                 return -EINVAL;
 779         } else if (rinfo->prefix_len > 64) {
 780                 if (rinfo->length < 2) {
 781                         return -EINVAL;
 782                 }
 783         } else if (rinfo->prefix_len > 0) {
 784                 if (rinfo->length < 1) {
 785                         return -EINVAL;
 786                 }
 787         }
 788
 789         pref = rinfo->route_pref;
 790         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 791                 return -EINVAL;
 792
 793         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 794
 795         if (rinfo->length == 3)
 796                 prefix = (struct in6_addr *)rinfo->prefix;
 797         else {
 798                 /* this function is safe */
 799                 ipv6_addr_prefix(&prefix_buf,
 800                                  (struct in6_addr *)rinfo->prefix,
 801                                  rinfo->prefix_len);
 802                 prefix = &prefix_buf;
 803         }
 804
 805         if (rinfo->prefix_len == 0)
 806                 rt = rt6_get_dflt_router(gwaddr, dev);
 807         else
 808                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 809                                         gwaddr, dev);
 810
 811         if (rt && !lifetime) {
 812                 ip6_del_rt(rt);
 813                 rt = NULL;
 814         }
 815
 816         if (!rt && lifetime)
 817                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
 818                                         dev, pref);
 819         else if (rt)
 820                 rt->rt6i_flags = RTF_ROUTEINFO |
 821                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 822
 823         if (rt) {
 824                 if (!addrconf_finite_timeout(lifetime))
 825                         rt6_clean_expires(rt);
 826                 else
 827                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 828
 829                 ip6_rt_put(rt);
 830         }
 831         return 0;
 832 }
 833 #endif
 834
 835 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 836                                         struct in6_addr *saddr)
 837 {
 838         struct fib6_node *pn;
 839         while (1) {
 840                 if (fn->fn_flags & RTN_TL_ROOT)
 841                         return NULL;
 842                 pn = fn->parent;
 843                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 844                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 845                 else
 846                         fn = pn;
 847                 if (fn->fn_flags & RTN_RTINFO)
 848                         return fn;
 849         }
 850 }
 851
 852 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 853                                              struct fib6_table *table,
 854                                              struct flowi6 *fl6, int flags)
 855 {
 856         struct fib6_node *fn;
 857         struct rt6_info *rt;
 858
 859         read_lock_bh(&table->tb6_lock);
 860         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 861 restart:
 862         rt = fn->leaf;
 863         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 864         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 865                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 866         if (rt == net->ipv6.ip6_null_entry) {
 867                 fn = fib6_backtrack(fn, &fl6->saddr);
 868                 if (fn)
 869                         goto restart;
 870         }
 871         dst_use(&rt->dst, jiffies);
 872         read_unlock_bh(&table->tb6_lock);
 873
 874         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
 875
 876         return rt;
 877
 878 }
 879
 880 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 881                                     int flags)
 882 {
 883         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 884 }
 885 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 886
 887 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 888                             const struct in6_addr *saddr, int oif, int strict)
 889 {
 890         struct flowi6 fl6 = {
 891                 .flowi6_oif = oif,
 892                 .daddr = *daddr,
 893         };
 894         struct dst_entry *dst;
 895         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 896
 897         if (saddr) {
 898                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 899                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 900         }
 901
 902         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 903         if (dst->error == 0)
 904                 return (struct rt6_info *) dst;
 905
 906         dst_release(dst);
 907
 908         return NULL;
 909 }
 910 EXPORT_SYMBOL(rt6_lookup);
 911
 912 /* ip6_ins_rt is called with FREE table->tb6_lock.
 913    It takes new route entry, the addition fails by any reason the
 914    route is freed. In any case, if caller does not hold it, it may
 915    be destroyed.
 916  */
 917
 918 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 919                         struct mx6_config *mxc)
 920 {
 921         int err;
 922         struct fib6_table *table;
 923
 924         table = rt->rt6i_table;
 925         write_lock_bh(&table->tb6_lock);
 926         err = fib6_add(&table->tb6_root, rt, info, mxc);
 927         write_unlock_bh(&table->tb6_lock);
 928
 929         return err;
 930 }
 931
 932 int ip6_ins_rt(struct rt6_info *rt)
 933 {
 934         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 935         struct mx6_config mxc = { .mx = NULL, };
 936
 937         return __ip6_ins_rt(rt, &info, &mxc);
 938 }
 939
 940 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 941                                            const struct in6_addr *daddr,
 942                                            const struct in6_addr *saddr)
 943 {
 944         struct rt6_info *rt;
 945
 946         /*
 947          *      Clone the route.
 948          */
 949
 950         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 951                 ort = (struct rt6_info *)ort->dst.from;
 952
 953         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 954
 955         if (!rt)
 956                 return NULL;
 957
 958         ip6_rt_copy_init(rt, ort);
 959         rt->rt6i_flags |= RTF_CACHE;
 960         rt->rt6i_metric = 0;
 961         rt->dst.flags |= DST_HOST;
 962         rt->rt6i_dst.addr = *daddr;
 963         rt->rt6i_dst.plen = 128;
 964
 965         if (!rt6_is_gw_or_nonexthop(ort)) {
 966                 if (ort->rt6i_dst.plen != 128 &&
 967                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 968                         rt->rt6i_flags |= RTF_ANYCAST;
 969 #ifdef CONFIG_IPV6_SUBTREES
 970                 if (rt->rt6i_src.plen && saddr) {
 971                         rt->rt6i_src.addr = *saddr;
 972                         rt->rt6i_src.plen = 128;
 973                 }
 974 #endif
 975         }
 976
 977         return rt;
 978 }
 979
 980 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 981 {
 982         struct rt6_info *pcpu_rt;
 983
 984         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 985                                   rt->dst.dev, rt->dst.flags);
 986
 987         if (!pcpu_rt)
 988                 return NULL;
 989         ip6_rt_copy_init(pcpu_rt, rt);
 990         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 991         pcpu_rt->rt6i_flags |= RTF_PCPU;
 992         return pcpu_rt;
 993 }
 994
 995 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 996 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 997 {
 998         struct rt6_info *pcpu_rt, **p;
 999
1000         p = this_cpu_ptr(rt->rt6i_pcpu);
1001         pcpu_rt = *p;
1002
1003         if (pcpu_rt) {
1004                 dst_hold(&pcpu_rt->dst);
1005                 rt6_dst_from_metrics_check(pcpu_rt);
1006         }
1007         return pcpu_rt;
1008 }
1009
1010 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1011 {
1012         struct fib6_table *table = rt->rt6i_table;
1013         struct rt6_info *pcpu_rt, *prev, **p;
1014
1015         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1016         if (!pcpu_rt) {
1017                 struct net *net = dev_net(rt->dst.dev);
1018
1019                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1020                 return net->ipv6.ip6_null_entry;
1021         }
1022
1023         read_lock_bh(&table->tb6_lock);
1024         if (rt->rt6i_pcpu) {
1025                 p = this_cpu_ptr(rt->rt6i_pcpu);
1026                 prev = cmpxchg(p, NULL, pcpu_rt);
1027                 if (prev) {
1028                         /* If someone did it before us, return prev instead */
1029                         dst_destroy(&pcpu_rt->dst);
1030                         pcpu_rt = prev;
1031                 }
1032         } else {
1033                 /* rt has been removed from the fib6 tree
1034                  * before we have a chance to acquire the read_lock.
1035                  * In this case, don't brother to create a pcpu rt
1036                  * since rt is going away anyway.  The next
1037                  * dst_check() will trigger a re-lookup.
1038                  */
1039                 dst_destroy(&pcpu_rt->dst);
1040                 pcpu_rt = rt;
1041         }
1042         dst_hold(&pcpu_rt->dst);
1043         rt6_dst_from_metrics_check(pcpu_rt);
1044         read_unlock_bh(&table->tb6_lock);
1045         return pcpu_rt;
1046 }
1047
1048 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
1049                                int oif, struct flowi6 *fl6, int flags)
1050 {
1051         struct fib6_node *fn, *saved_fn;
1052         struct rt6_info *rt;
1053         int strict = 0;
1054
1055         strict |= flags & RT6_LOOKUP_F_IFACE;
1056         strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
1057         if (net->ipv6.devconf_all->forwarding == 0)
1058                 strict |= RT6_LOOKUP_F_REACHABLE;
1059
1060         read_lock_bh(&table->tb6_lock);
1061
1062         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1063         saved_fn = fn;
1064
1065         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1066                 oif = 0;
1067
1068 redo_rt6_select:
1069         rt = rt6_select(fn, oif, strict);
1070         if (rt->rt6i_nsiblings)
1071                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1072         if (rt == net->ipv6.ip6_null_entry) {
1073                 fn = fib6_backtrack(fn, &fl6->saddr);
1074                 if (fn)
1075                         goto redo_rt6_select;
1076                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1077                         /* also consider unreachable route */
1078                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1079                         fn = saved_fn;
1080                         goto redo_rt6_select;
1081                 }
1082         }
1083
1084
1085         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1086                 dst_use(&rt->dst, jiffies);
1087                 read_unlock_bh(&table->tb6_lock);
1088
1089                 rt6_dst_from_metrics_check(rt);
1090
1091                 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1092                 return rt;
1093         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1094                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1095                 /* Create a RTF_CACHE clone which will not be
1096                  * owned by the fib6 tree.  It is for the special case where
1097                  * the daddr in the skb during the neighbor look-up is different
1098                  * from the fl6->daddr used to look-up route here.
1099                  */
1100
1101                 struct rt6_info *uncached_rt;
1102
1103                 dst_use(&rt->dst, jiffies);
1104                 read_unlock_bh(&table->tb6_lock);
1105
1106                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1107                 dst_release(&rt->dst);
1108
1109                 if (uncached_rt)
1110                         rt6_uncached_list_add(uncached_rt);
1111                 else
1112                         uncached_rt = net->ipv6.ip6_null_entry;
1113
1114                 dst_hold(&uncached_rt->dst);
1115
1116                 trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
1117                 return uncached_rt;
1118
1119         } else {
1120                 /* Get a percpu copy */
1121
1122                 struct rt6_info *pcpu_rt;
1123
1124                 rt->dst.lastuse = jiffies;
1125                 rt->dst.__use++;
1126                 pcpu_rt = rt6_get_pcpu_route(rt);
1127
1128                 if (pcpu_rt) {
1129                         read_unlock_bh(&table->tb6_lock);
1130                 } else {
1131                         /* We have to do the read_unlock first
1132                          * because rt6_make_pcpu_route() may trigger
1133                          * ip6_dst_gc() which will take the write_lock.
1134                          */
1135                         dst_hold(&rt->dst);
1136                         read_unlock_bh(&table->tb6_lock);
1137                         pcpu_rt = rt6_make_pcpu_route(rt);
1138                         dst_release(&rt->dst);
1139                 }
1140
1141                 trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
1142                 return pcpu_rt;
1143
1144         }
1145 }
1146 EXPORT_SYMBOL_GPL(ip6_pol_route);
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 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 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
1164
1165 void ip6_route_input(struct sk_buff *skb)
1166 {
1167         const struct ipv6hdr *iph = ipv6_hdr(skb);
1168         struct net *net = dev_net(skb->dev);
1169         int flags = RT6_LOOKUP_F_HAS_SADDR;
1170         struct ip_tunnel_info *tun_info;
1171         struct flowi6 fl6 = {
1172                 .flowi6_iif = skb->dev->ifindex,
1173                 .daddr = iph->daddr,
1174                 .saddr = iph->saddr,
1175                 .flowlabel = ip6_flowinfo(iph),
1176                 .flowi6_mark = skb->mark,
1177                 .flowi6_proto = iph->nexthdr,
1178         };
1179
1180         tun_info = skb_tunnel_info(skb);
1181         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1182                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1183         skb_dst_drop(skb);
1184         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1185 }
1186
1187 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1188                                              struct flowi6 *fl6, int flags)
1189 {
1190         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1191 }
1192
1193 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1194                                          struct flowi6 *fl6, int flags)
1195 {
1196         bool any_src;
1197
1198         if (rt6_need_strict(&fl6->daddr)) {
1199                 struct dst_entry *dst;
1200
1201                 dst = l3mdev_link_scope_lookup(net, fl6);
1202                 if (dst)
1203                         return dst;
1204         }
1205
1206         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1207
1208         any_src = ipv6_addr_any(&fl6->saddr);
1209         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1210             (fl6->flowi6_oif && any_src))
1211                 flags |= RT6_LOOKUP_F_IFACE;
1212
1213         if (!any_src)
1214                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1215         else if (sk)
1216                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1217
1218         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1219 }
1220 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1221
1222 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1223 {
1224         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1225         struct dst_entry *new = NULL;
1226
1227         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1228         if (rt) {
1229                 rt6_info_init(rt);
1230
1231                 new = &rt->dst;
1232                 new->__use = 1;
1233                 new->input = dst_discard;
1234                 new->output = dst_discard_out;
1235
1236                 dst_copy_metrics(new, &ort->dst);
1237                 rt->rt6i_idev = ort->rt6i_idev;
1238                 if (rt->rt6i_idev)
1239                         in6_dev_hold(rt->rt6i_idev);
1240
1241                 rt->rt6i_gateway = ort->rt6i_gateway;
1242                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1243                 rt->rt6i_metric = 0;
1244
1245                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1246 #ifdef CONFIG_IPV6_SUBTREES
1247                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1248 #endif
1249
1250                 dst_free(new);
1251         }
1252
1253         dst_release(dst_orig);
1254         return new ? new : ERR_PTR(-ENOMEM);
1255 }
1256
1257 /*
1258  *      Destination cache support functions
1259  */
1260
1261 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1262 {
1263         if (rt->dst.from &&
1264             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1265                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1266 }
1267
1268 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1269 {
1270         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1271                 return NULL;
1272
1273         if (rt6_check_expired(rt))
1274                 return NULL;
1275
1276         return &rt->dst;
1277 }
1278
1279 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1280 {
1281         if (!__rt6_check_expired(rt) &&
1282             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1283             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1284                 return &rt->dst;
1285         else
1286                 return NULL;
1287 }
1288
1289 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1290 {
1291         struct rt6_info *rt;
1292
1293         rt = (struct rt6_info *) dst;
1294
1295         /* All IPV6 dsts are created with ->obsolete set to the value
1296          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1297          * into this function always.
1298          */
1299
1300         rt6_dst_from_metrics_check(rt);
1301
1302         if (rt->rt6i_flags & RTF_PCPU ||
1303             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1304                 return rt6_dst_from_check(rt, cookie);
1305         else
1306                 return rt6_check(rt, cookie);
1307 }
1308
1309 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1310 {
1311         struct rt6_info *rt = (struct rt6_info *) dst;
1312
1313         if (rt) {
1314                 if (rt->rt6i_flags & RTF_CACHE) {
1315                         if (rt6_check_expired(rt)) {
1316                                 ip6_del_rt(rt);
1317                                 dst = NULL;
1318                         }
1319                 } else {
1320                         dst_release(dst);
1321                         dst = NULL;
1322                 }
1323         }
1324         return dst;
1325 }
1326
1327 static void ip6_link_failure(struct sk_buff *skb)
1328 {
1329         struct rt6_info *rt;
1330
1331         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1332
1333         rt = (struct rt6_info *) skb_dst(skb);
1334         if (rt) {
1335                 if (rt->rt6i_flags & RTF_CACHE) {
1336                         dst_hold(&rt->dst);
1337                         ip6_del_rt(rt);
1338                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1339                         rt->rt6i_node->fn_sernum = -1;
1340                 }
1341         }
1342 }
1343
1344 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1345 {
1346         struct net *net = dev_net(rt->dst.dev);
1347
1348         rt->rt6i_flags |= RTF_MODIFIED;
1349         rt->rt6i_pmtu = mtu;
1350         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1351 }
1352
1353 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1354 {
1355         return !(rt->rt6i_flags & RTF_CACHE) &&
1356                 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1357 }
1358
1359 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1360                                  const struct ipv6hdr *iph, u32 mtu)
1361 {
1362         struct rt6_info *rt6 = (struct rt6_info *)dst;
1363
1364         if (rt6->rt6i_flags & RTF_LOCAL)
1365                 return;
1366
1367         if (dst_metric_locked(dst, RTAX_MTU))
1368                 return;
1369
1370         dst_confirm(dst);
1371         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1372         if (mtu >= dst_mtu(dst))
1373                 return;
1374
1375         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1376                 rt6_do_update_pmtu(rt6, mtu);
1377         } else {
1378                 const struct in6_addr *daddr, *saddr;
1379                 struct rt6_info *nrt6;
1380
1381                 if (iph) {
1382                         daddr = &iph->daddr;
1383                         saddr = &iph->saddr;
1384                 } else if (sk) {
1385                         daddr = &sk->sk_v6_daddr;
1386                         saddr = &inet6_sk(sk)->saddr;
1387                 } else {
1388                         return;
1389                 }
1390                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1391                 if (nrt6) {
1392                         rt6_do_update_pmtu(nrt6, mtu);
1393
1394                         /* ip6_ins_rt(nrt6) will bump the
1395                          * rt6->rt6i_node->fn_sernum
1396                          * which will fail the next rt6_check() and
1397                          * invalidate the sk->sk_dst_cache.
1398                          */
1399                         ip6_ins_rt(nrt6);
1400                 }
1401         }
1402 }
1403
1404 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1405                                struct sk_buff *skb, u32 mtu)
1406 {
1407         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1408 }
1409
1410 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1411                      int oif, u32 mark, kuid_t uid)
1412 {
1413         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1414         struct dst_entry *dst;
1415         struct flowi6 fl6;
1416
1417         memset(&fl6, 0, sizeof(fl6));
1418         fl6.flowi6_oif = oif;
1419         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1420         fl6.daddr = iph->daddr;
1421         fl6.saddr = iph->saddr;
1422         fl6.flowlabel = ip6_flowinfo(iph);
1423         fl6.flowi6_uid = uid;
1424
1425         dst = ip6_route_output(net, NULL, &fl6);
1426         if (!dst->error)
1427                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1428         dst_release(dst);
1429 }
1430 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1431
1432 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1433 {
1434         struct dst_entry *dst;
1435
1436         ip6_update_pmtu(skb, sock_net(sk), mtu,
1437                         sk->sk_bound_dev_if, sk->sk_mark, sk->sk_uid);
1438
1439         dst = __sk_dst_get(sk);
1440         if (!dst || !dst->obsolete ||
1441             dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
1442                 return;
1443
1444         bh_lock_sock(sk);
1445         if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1446                 ip6_datagram_dst_update(sk, false);
1447         bh_unlock_sock(sk);
1448 }
1449 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1450
1451 /* Handle redirects */
1452 struct ip6rd_flowi {
1453         struct flowi6 fl6;
1454         struct in6_addr gateway;
1455 };
1456
1457 static struct rt6_info *__ip6_route_redirect(struct net *net,
1458                                              struct fib6_table *table,
1459                                              struct flowi6 *fl6,
1460                                              int flags)
1461 {
1462         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1463         struct rt6_info *rt;
1464         struct fib6_node *fn;
1465
1466         /* Get the "current" route for this destination and
1467          * check if the redirect has come from approriate router.
1468          *
1469          * RFC 4861 specifies that redirects should only be
1470          * accepted if they come from the nexthop to the target.
1471          * Due to the way the routes are chosen, this notion
1472          * is a bit fuzzy and one might need to check all possible
1473          * routes.
1474          */
1475
1476         read_lock_bh(&table->tb6_lock);
1477         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1478 restart:
1479         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1480                 if (rt6_check_expired(rt))
1481                         continue;
1482                 if (rt->dst.error)
1483                         break;
1484                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1485                         continue;
1486                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1487                         continue;
1488                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1489                         continue;
1490                 break;
1491         }
1492
1493         if (!rt)
1494                 rt = net->ipv6.ip6_null_entry;
1495         else if (rt->dst.error) {
1496                 rt = net->ipv6.ip6_null_entry;
1497                 goto out;
1498         }
1499
1500         if (rt == net->ipv6.ip6_null_entry) {
1501                 fn = fib6_backtrack(fn, &fl6->saddr);
1502                 if (fn)
1503                         goto restart;
1504         }
1505
1506 out:
1507         dst_hold(&rt->dst);
1508
1509         read_unlock_bh(&table->tb6_lock);
1510
1511         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1512         return rt;
1513 };
1514
1515 static struct dst_entry *ip6_route_redirect(struct net *net,
1516                                         const struct flowi6 *fl6,
1517                                         const struct in6_addr *gateway)
1518 {
1519         int flags = RT6_LOOKUP_F_HAS_SADDR;
1520         struct ip6rd_flowi rdfl;
1521
1522         rdfl.fl6 = *fl6;
1523         rdfl.gateway = *gateway;
1524
1525         return fib6_rule_lookup(net, &rdfl.fl6,
1526                                 flags, __ip6_route_redirect);
1527 }
1528
1529 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
1530                   kuid_t uid)
1531 {
1532         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1533         struct dst_entry *dst;
1534         struct flowi6 fl6;
1535
1536         memset(&fl6, 0, sizeof(fl6));
1537         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1538         fl6.flowi6_oif = oif;
1539         fl6.flowi6_mark = mark;
1540         fl6.daddr = iph->daddr;
1541         fl6.saddr = iph->saddr;
1542         fl6.flowlabel = ip6_flowinfo(iph);
1543         fl6.flowi6_uid = uid;
1544
1545         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1546         rt6_do_redirect(dst, NULL, skb);
1547         dst_release(dst);
1548 }
1549 EXPORT_SYMBOL_GPL(ip6_redirect);
1550
1551 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1552                             u32 mark)
1553 {
1554         const struct ipv6hdr *iph = ipv6_hdr(skb);
1555         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1556         struct dst_entry *dst;
1557         struct flowi6 fl6;
1558
1559         memset(&fl6, 0, sizeof(fl6));
1560         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1561         fl6.flowi6_oif = oif;
1562         fl6.flowi6_mark = mark;
1563         fl6.daddr = msg->dest;
1564         fl6.saddr = iph->daddr;
1565         fl6.flowi6_uid = sock_net_uid(net, NULL);
1566
1567         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1568         rt6_do_redirect(dst, NULL, skb);
1569         dst_release(dst);
1570 }
1571
1572 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1573 {
1574         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
1575                      sk->sk_uid);
1576 }
1577 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1578
1579 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1580 {
1581         struct net_device *dev = dst->dev;
1582         unsigned int mtu = dst_mtu(dst);
1583         struct net *net = dev_net(dev);
1584
1585         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1586
1587         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1588                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1589
1590         /*
1591          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1592          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1593          * IPV6_MAXPLEN is also valid and means: "any MSS,
1594          * rely only on pmtu discovery"
1595          */
1596         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1597                 mtu = IPV6_MAXPLEN;
1598         return mtu;
1599 }
1600
1601 static unsigned int ip6_mtu(const struct dst_entry *dst)
1602 {
1603         const struct rt6_info *rt = (const struct rt6_info *)dst;
1604         unsigned int mtu = rt->rt6i_pmtu;
1605         struct inet6_dev *idev;
1606
1607         if (mtu)
1608                 goto out;
1609
1610         mtu = dst_metric_raw(dst, RTAX_MTU);
1611         if (mtu)
1612                 goto out;
1613
1614         mtu = IPV6_MIN_MTU;
1615
1616         rcu_read_lock();
1617         idev = __in6_dev_get(dst->dev);
1618         if (idev)
1619                 mtu = idev->cnf.mtu6;
1620         rcu_read_unlock();
1621
1622 out:
1623         mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1624
1625         return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
1626 }
1627
1628 static struct dst_entry *icmp6_dst_gc_list;
1629 static DEFINE_SPINLOCK(icmp6_dst_lock);
1630
1631 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1632                                   struct flowi6 *fl6)
1633 {
1634         struct dst_entry *dst;
1635         struct rt6_info *rt;
1636         struct inet6_dev *idev = in6_dev_get(dev);
1637         struct net *net = dev_net(dev);
1638
1639         if (unlikely(!idev))
1640                 return ERR_PTR(-ENODEV);
1641
1642         rt = ip6_dst_alloc(net, dev, 0);
1643         if (unlikely(!rt)) {
1644                 in6_dev_put(idev);
1645                 dst = ERR_PTR(-ENOMEM);
1646                 goto out;
1647         }
1648
1649         rt->dst.flags |= DST_HOST;
1650         rt->dst.output  = ip6_output;
1651         atomic_set(&rt->dst.__refcnt, 1);
1652         rt->rt6i_gateway  = fl6->daddr;
1653         rt->rt6i_dst.addr = fl6->daddr;
1654         rt->rt6i_dst.plen = 128;
1655         rt->rt6i_idev     = idev;
1656         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1657
1658         spin_lock_bh(&icmp6_dst_lock);
1659         rt->dst.next = icmp6_dst_gc_list;
1660         icmp6_dst_gc_list = &rt->dst;
1661         spin_unlock_bh(&icmp6_dst_lock);
1662
1663         fib6_force_start_gc(net);
1664
1665         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1666
1667 out:
1668         return dst;
1669 }
1670
1671 int icmp6_dst_gc(void)
1672 {
1673         struct dst_entry *dst, **pprev;
1674         int more = 0;
1675
1676         spin_lock_bh(&icmp6_dst_lock);
1677         pprev = &icmp6_dst_gc_list;
1678
1679         while ((dst = *pprev) != NULL) {
1680                 if (!atomic_read(&dst->__refcnt)) {
1681                         *pprev = dst->next;
1682                         dst_free(dst);
1683                 } else {
1684                         pprev = &dst->next;
1685                         ++more;
1686                 }
1687         }
1688
1689         spin_unlock_bh(&icmp6_dst_lock);
1690
1691         return more;
1692 }
1693
1694 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1695                             void *arg)
1696 {
1697         struct dst_entry *dst, **pprev;
1698
1699         spin_lock_bh(&icmp6_dst_lock);
1700         pprev = &icmp6_dst_gc_list;
1701         while ((dst = *pprev) != NULL) {
1702                 struct rt6_info *rt = (struct rt6_info *) dst;
1703                 if (func(rt, arg)) {
1704                         *pprev = dst->next;
1705                         dst_free(dst);
1706                 } else {
1707                         pprev = &dst->next;
1708                 }
1709         }
1710         spin_unlock_bh(&icmp6_dst_lock);
1711 }
1712
1713 static int ip6_dst_gc(struct dst_ops *ops)
1714 {
1715         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1716         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1717         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1718         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1719         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1720         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1721         int entries;
1722
1723         entries = dst_entries_get_fast(ops);
1724         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1725             entries <= rt_max_size)
1726                 goto out;
1727
1728         net->ipv6.ip6_rt_gc_expire++;
1729         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1730         entries = dst_entries_get_slow(ops);
1731         if (entries < ops->gc_thresh)
1732                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1733 out:
1734         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1735         return entries > rt_max_size;
1736 }
1737
1738 static int ip6_convert_metrics(struct mx6_config *mxc,
1739                                const struct fib6_config *cfg)
1740 {
1741         bool ecn_ca = false;
1742         struct nlattr *nla;
1743         int remaining;
1744         u32 *mp;
1745
1746         if (!cfg->fc_mx)
1747                 return 0;
1748
1749         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1750         if (unlikely(!mp))
1751                 return -ENOMEM;
1752
1753         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1754                 int type = nla_type(nla);
1755                 u32 val;
1756
1757                 if (!type)
1758                         continue;
1759                 if (unlikely(type > RTAX_MAX))
1760                         goto err;
1761
1762                 if (type == RTAX_CC_ALGO) {
1763                         char tmp[TCP_CA_NAME_MAX];
1764
1765                         nla_strlcpy(tmp, nla, sizeof(tmp));
1766                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1767                         if (val == TCP_CA_UNSPEC)
1768                                 goto err;
1769                 } else {
1770                         val = nla_get_u32(nla);
1771                 }
1772                 if (type == RTAX_HOPLIMIT && val > 255)
1773                         val = 255;
1774                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1775                         goto err;
1776
1777                 mp[type - 1] = val;
1778                 __set_bit(type - 1, mxc->mx_valid);
1779         }
1780
1781         if (ecn_ca) {
1782                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1783                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1784         }
1785
1786         mxc->mx = mp;
1787         return 0;
1788  err:
1789         kfree(mp);
1790         return -EINVAL;
1791 }
1792
1793 static struct rt6_info *ip6_nh_lookup_table(struct net *net,
1794                                             struct fib6_config *cfg,
1795                                             const struct in6_addr *gw_addr)
1796 {
1797         struct flowi6 fl6 = {
1798                 .flowi6_oif = cfg->fc_ifindex,
1799                 .daddr = *gw_addr,
1800                 .saddr = cfg->fc_prefsrc,
1801         };
1802         struct fib6_table *table;
1803         struct rt6_info *rt;
1804         int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_IGNORE_LINKSTATE;
1805
1806         table = fib6_get_table(net, cfg->fc_table);
1807         if (!table)
1808                 return NULL;
1809
1810         if (!ipv6_addr_any(&cfg->fc_prefsrc))
1811                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1812
1813         rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags);
1814
1815         /* if table lookup failed, fall back to full lookup */
1816         if (rt == net->ipv6.ip6_null_entry) {
1817                 ip6_rt_put(rt);
1818                 rt = NULL;
1819         }
1820
1821         return rt;
1822 }
1823
1824 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1825 {
1826         struct net *net = cfg->fc_nlinfo.nl_net;
1827         struct rt6_info *rt = NULL;
1828         struct net_device *dev = NULL;
1829         struct inet6_dev *idev = NULL;
1830         struct fib6_table *table;
1831         int addr_type;
1832         int err = -EINVAL;
1833
1834         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1835                 goto out;
1836 #ifndef CONFIG_IPV6_SUBTREES
1837         if (cfg->fc_src_len)
1838                 goto out;
1839 #endif
1840         if (cfg->fc_ifindex) {
1841                 err = -ENODEV;
1842                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1843                 if (!dev)
1844                         goto out;
1845                 idev = in6_dev_get(dev);
1846                 if (!idev)
1847                         goto out;
1848         }
1849
1850         if (cfg->fc_metric == 0)
1851                 cfg->fc_metric = IP6_RT_PRIO_USER;
1852
1853         err = -ENOBUFS;
1854         if (cfg->fc_nlinfo.nlh &&
1855             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1856                 table = fib6_get_table(net, cfg->fc_table);
1857                 if (!table) {
1858                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1859                         table = fib6_new_table(net, cfg->fc_table);
1860                 }
1861         } else {
1862                 table = fib6_new_table(net, cfg->fc_table);
1863         }
1864
1865         if (!table)
1866                 goto out;
1867
1868         rt = ip6_dst_alloc(net, NULL,
1869                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1870
1871         if (!rt) {
1872                 err = -ENOMEM;
1873                 goto out;
1874         }
1875
1876         if (cfg->fc_flags & RTF_EXPIRES)
1877                 rt6_set_expires(rt, jiffies +
1878                                 clock_t_to_jiffies(cfg->fc_expires));
1879         else
1880                 rt6_clean_expires(rt);
1881
1882         if (cfg->fc_protocol == RTPROT_UNSPEC)
1883                 cfg->fc_protocol = RTPROT_BOOT;
1884         rt->rt6i_protocol = cfg->fc_protocol;
1885
1886         addr_type = ipv6_addr_type(&cfg->fc_dst);
1887
1888         if (addr_type & IPV6_ADDR_MULTICAST)
1889                 rt->dst.input = ip6_mc_input;
1890         else if (cfg->fc_flags & RTF_LOCAL)
1891                 rt->dst.input = ip6_input;
1892         else
1893                 rt->dst.input = ip6_forward;
1894
1895         rt->dst.output = ip6_output;
1896
1897         if (cfg->fc_encap) {
1898                 struct lwtunnel_state *lwtstate;
1899
1900                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1901                                            cfg->fc_encap, AF_INET6, cfg,
1902                                            &lwtstate);
1903                 if (err)
1904                         goto out;
1905                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1906                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1907                         rt->dst.lwtstate->orig_output = rt->dst.output;
1908                         rt->dst.output = lwtunnel_output;
1909                 }
1910                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1911                         rt->dst.lwtstate->orig_input = rt->dst.input;
1912                         rt->dst.input = lwtunnel_input;
1913                 }
1914         }
1915
1916         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1917         rt->rt6i_dst.plen = cfg->fc_dst_len;
1918         if (rt->rt6i_dst.plen == 128)
1919                 rt->dst.flags |= DST_HOST;
1920
1921 #ifdef CONFIG_IPV6_SUBTREES
1922         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1923         rt->rt6i_src.plen = cfg->fc_src_len;
1924 #endif
1925
1926         rt->rt6i_metric = cfg->fc_metric;
1927
1928         /* We cannot add true routes via loopback here,
1929            they would result in kernel looping; promote them to reject routes
1930          */
1931         if ((cfg->fc_flags & RTF_REJECT) ||
1932             (dev && (dev->flags & IFF_LOOPBACK) &&
1933              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1934              !(cfg->fc_flags & RTF_LOCAL))) {
1935                 /* hold loopback dev/idev if we haven't done so. */
1936                 if (dev != net->loopback_dev) {
1937                         if (dev) {
1938                                 dev_put(dev);
1939                                 in6_dev_put(idev);
1940                         }
1941                         dev = net->loopback_dev;
1942                         dev_hold(dev);
1943                         idev = in6_dev_get(dev);
1944                         if (!idev) {
1945                                 err = -ENODEV;
1946                                 goto out;
1947                         }
1948                 }
1949                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1950                 switch (cfg->fc_type) {
1951                 case RTN_BLACKHOLE:
1952                         rt->dst.error = -EINVAL;
1953                         rt->dst.output = dst_discard_out;
1954                         rt->dst.input = dst_discard;
1955                         break;
1956                 case RTN_PROHIBIT:
1957                         rt->dst.error = -EACCES;
1958                         rt->dst.output = ip6_pkt_prohibit_out;
1959                         rt->dst.input = ip6_pkt_prohibit;
1960                         break;
1961                 case RTN_THROW:
1962                 case RTN_UNREACHABLE:
1963                 default:
1964                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1965                                         : (cfg->fc_type == RTN_UNREACHABLE)
1966                                         ? -EHOSTUNREACH : -ENETUNREACH;
1967                         rt->dst.output = ip6_pkt_discard_out;
1968                         rt->dst.input = ip6_pkt_discard;
1969                         break;
1970                 }
1971                 goto install_route;
1972         }
1973
1974         if (cfg->fc_flags & RTF_GATEWAY) {
1975                 const struct in6_addr *gw_addr;
1976                 int gwa_type;
1977
1978                 gw_addr = &cfg->fc_gateway;
1979                 gwa_type = ipv6_addr_type(gw_addr);
1980
1981                 /* if gw_addr is local we will fail to detect this in case
1982                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1983                  * will return already-added prefix route via interface that
1984                  * prefix route was assigned to, which might be non-loopback.
1985                  */
1986                 err = -EINVAL;
1987                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1988                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1989                                             dev : NULL, 0, 0))
1990                         goto out;
1991
1992                 rt->rt6i_gateway = *gw_addr;
1993
1994                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1995                         struct rt6_info *grt = NULL;
1996
1997                         /* IPv6 strictly inhibits using not link-local
1998                            addresses as nexthop address.
1999                            Otherwise, router will not able to send redirects.
2000                            It is very good, but in some (rare!) circumstances
2001                            (SIT, PtP, NBMA NOARP links) it is handy to allow
2002                            some exceptions. --ANK
2003                            We allow IPv4-mapped nexthops to support RFC4798-type
2004                            addressing
2005                          */
2006                         if (!(gwa_type & (IPV6_ADDR_UNICAST |
2007                                           IPV6_ADDR_MAPPED)))
2008                                 goto out;
2009
2010                         if (cfg->fc_table) {
2011                                 grt = ip6_nh_lookup_table(net, cfg, gw_addr);
2012
2013                                 if (grt) {
2014                                         if (grt->rt6i_flags & RTF_GATEWAY ||
2015                                             (dev && dev != grt->dst.dev)) {
2016                                                 ip6_rt_put(grt);
2017                                                 grt = NULL;
2018                                         }
2019                                 }
2020                         }
2021
2022                         if (!grt)
2023                                 grt = rt6_lookup(net, gw_addr, NULL,
2024                                                  cfg->fc_ifindex, 1);
2025
2026                         err = -EHOSTUNREACH;
2027                         if (!grt)
2028                                 goto out;
2029                         if (dev) {
2030                                 if (dev != grt->dst.dev) {
2031                                         ip6_rt_put(grt);
2032                                         goto out;
2033                                 }
2034                         } else {
2035                                 dev = grt->dst.dev;
2036                                 idev = grt->rt6i_idev;
2037                                 dev_hold(dev);
2038                                 in6_dev_hold(grt->rt6i_idev);
2039                         }
2040                         if (!(grt->rt6i_flags & RTF_GATEWAY))
2041                                 err = 0;
2042                         ip6_rt_put(grt);
2043
2044                         if (err)
2045                                 goto out;
2046                 }
2047                 err = -EINVAL;
2048                 if (!dev || (dev->flags & IFF_LOOPBACK))
2049                         goto out;
2050         }
2051
2052         err = -ENODEV;
2053         if (!dev)
2054                 goto out;
2055
2056         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
2057                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
2058                         err = -EINVAL;
2059                         goto out;
2060                 }
2061                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
2062                 rt->rt6i_prefsrc.plen = 128;
2063         } else
2064                 rt->rt6i_prefsrc.plen = 0;
2065
2066         rt->rt6i_flags = cfg->fc_flags;
2067
2068 install_route:
2069         rt->dst.dev = dev;
2070         rt->rt6i_idev = idev;
2071         rt->rt6i_table = table;
2072
2073         cfg->fc_nlinfo.nl_net = dev_net(dev);
2074
2075         return rt;
2076 out:
2077         if (dev)
2078                 dev_put(dev);
2079         if (idev)
2080                 in6_dev_put(idev);
2081         if (rt)
2082                 dst_free(&rt->dst);
2083
2084         return ERR_PTR(err);
2085 }
2086
2087 int ip6_route_add(struct fib6_config *cfg)
2088 {
2089         struct mx6_config mxc = { .mx = NULL, };
2090         struct rt6_info *rt;
2091         int err;
2092
2093         rt = ip6_route_info_create(cfg);
2094         if (IS_ERR(rt)) {
2095                 err = PTR_ERR(rt);
2096                 rt = NULL;
2097                 goto out;
2098         }
2099
2100         err = ip6_convert_metrics(&mxc, cfg);
2101         if (err)
2102                 goto out;
2103
2104         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2105
2106         kfree(mxc.mx);
2107
2108         return err;
2109 out:
2110         if (rt)
2111                 dst_free(&rt->dst);
2112
2113         return err;
2114 }
2115
2116 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2117 {
2118         int err;
2119         struct fib6_table *table;
2120         struct net *net = dev_net(rt->dst.dev);
2121
2122         if (rt == net->ipv6.ip6_null_entry ||
2123             rt->dst.flags & DST_NOCACHE) {
2124                 err = -ENOENT;
2125                 goto out;
2126         }
2127
2128         table = rt->rt6i_table;
2129         write_lock_bh(&table->tb6_lock);
2130         err = fib6_del(rt, info);
2131         write_unlock_bh(&table->tb6_lock);
2132
2133 out:
2134         ip6_rt_put(rt);
2135         return err;
2136 }
2137
2138 int ip6_del_rt(struct rt6_info *rt)
2139 {
2140         struct nl_info info = {
2141                 .nl_net = dev_net(rt->dst.dev),
2142         };
2143         return __ip6_del_rt(rt, &info);
2144 }
2145
2146 static int ip6_route_del(struct fib6_config *cfg)
2147 {
2148         struct fib6_table *table;
2149         struct fib6_node *fn;
2150         struct rt6_info *rt;
2151         int err = -ESRCH;
2152
2153         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2154         if (!table)
2155                 return err;
2156
2157         read_lock_bh(&table->tb6_lock);
2158
2159         fn = fib6_locate(&table->tb6_root,
2160                          &cfg->fc_dst, cfg->fc_dst_len,
2161                          &cfg->fc_src, cfg->fc_src_len);
2162
2163         if (fn) {
2164                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2165                         if ((rt->rt6i_flags & RTF_CACHE) &&
2166                             !(cfg->fc_flags & RTF_CACHE))
2167                                 continue;
2168                         if (cfg->fc_ifindex &&
2169                             (!rt->dst.dev ||
2170                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2171                                 continue;
2172                         if (cfg->fc_flags & RTF_GATEWAY &&
2173                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2174                                 continue;
2175                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2176                                 continue;
2177                         dst_hold(&rt->dst);
2178                         read_unlock_bh(&table->tb6_lock);
2179
2180                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2181                 }
2182         }
2183         read_unlock_bh(&table->tb6_lock);
2184
2185         return err;
2186 }
2187
2188 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2189 {
2190         struct netevent_redirect netevent;
2191         struct rt6_info *rt, *nrt = NULL;
2192         struct ndisc_options ndopts;
2193         struct inet6_dev *in6_dev;
2194         struct neighbour *neigh;
2195         struct rd_msg *msg;
2196         int optlen, on_link;
2197         u8 *lladdr;
2198
2199         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2200         optlen -= sizeof(*msg);
2201
2202         if (optlen < 0) {
2203                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2204                 return;
2205         }
2206
2207         msg = (struct rd_msg *)icmp6_hdr(skb);
2208
2209         if (ipv6_addr_is_multicast(&msg->dest)) {
2210                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2211                 return;
2212         }
2213
2214         on_link = 0;
2215         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2216                 on_link = 1;
2217         } else if (ipv6_addr_type(&msg->target) !=
2218                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2219                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2220                 return;
2221         }
2222
2223         in6_dev = __in6_dev_get(skb->dev);
2224         if (!in6_dev)
2225                 return;
2226         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2227                 return;
2228
2229         /* RFC2461 8.1:
2230          *      The IP source address of the Redirect MUST be the same as the current
2231          *      first-hop router for the specified ICMP Destination Address.
2232          */
2233
2234         if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
2235                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2236                 return;
2237         }
2238
2239         lladdr = NULL;
2240         if (ndopts.nd_opts_tgt_lladdr) {
2241                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2242                                              skb->dev);
2243                 if (!lladdr) {
2244                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2245                         return;
2246                 }
2247         }
2248
2249         rt = (struct rt6_info *) dst;
2250         if (rt->rt6i_flags & RTF_REJECT) {
2251                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2252                 return;
2253         }
2254
2255         /* Redirect received -> path was valid.
2256          * Look, redirects are sent only in response to data packets,
2257          * so that this nexthop apparently is reachable. --ANK
2258          */
2259         dst_confirm(&rt->dst);
2260
2261         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2262         if (!neigh)
2263                 return;
2264
2265         /*
2266          *      We have finally decided to accept it.
2267          */
2268
2269         ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
2270                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2271                      NEIGH_UPDATE_F_OVERRIDE|
2272                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2273                                      NEIGH_UPDATE_F_ISROUTER)),
2274                      NDISC_REDIRECT, &ndopts);
2275
2276         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2277         if (!nrt)
2278                 goto out;
2279
2280         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2281         if (on_link)
2282                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2283
2284         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2285
2286         if (ip6_ins_rt(nrt))
2287                 goto out;
2288
2289         netevent.old = &rt->dst;
2290         netevent.new = &nrt->dst;
2291         netevent.daddr = &msg->dest;
2292         netevent.neigh = neigh;
2293         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2294
2295         if (rt->rt6i_flags & RTF_CACHE) {
2296                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2297                 ip6_del_rt(rt);
2298         }
2299
2300 out:
2301         neigh_release(neigh);
2302 }
2303
2304 /*
2305  *      Misc support functions
2306  */
2307
2308 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2309 {
2310         BUG_ON(from->dst.from);
2311
2312         rt->rt6i_flags &= ~RTF_EXPIRES;
2313         dst_hold(&from->dst);
2314         rt->dst.from = &from->dst;
2315         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2316 }
2317
2318 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2319 {
2320         rt->dst.input = ort->dst.input;
2321         rt->dst.output = ort->dst.output;
2322         rt->rt6i_dst = ort->rt6i_dst;
2323         rt->dst.error = ort->dst.error;
2324         rt->rt6i_idev = ort->rt6i_idev;
2325         if (rt->rt6i_idev)
2326                 in6_dev_hold(rt->rt6i_idev);
2327         rt->dst.lastuse = jiffies;
2328         rt->rt6i_gateway = ort->rt6i_gateway;
2329         rt->rt6i_flags = ort->rt6i_flags;
2330         rt6_set_from(rt, ort);
2331         rt->rt6i_metric = ort->rt6i_metric;
2332 #ifdef CONFIG_IPV6_SUBTREES
2333         rt->rt6i_src = ort->rt6i_src;
2334 #endif
2335         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2336         rt->rt6i_table = ort->rt6i_table;
2337         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2338 }
2339
2340 #ifdef CONFIG_IPV6_ROUTE_INFO
2341 static struct rt6_info *rt6_get_route_info(struct net *net,
2342                                            const struct in6_addr *prefix, int prefixlen,
2343                                            const struct in6_addr *gwaddr,
2344                                            struct net_device *dev)
2345 {
2346         u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
2347         int ifindex = dev->ifindex;
2348         struct fib6_node *fn;
2349         struct rt6_info *rt = NULL;
2350         struct fib6_table *table;
2351
2352         table = fib6_get_table(net, tb_id);
2353         if (!table)
2354                 return NULL;
2355
2356         read_lock_bh(&table->tb6_lock);
2357         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2358         if (!fn)
2359                 goto out;
2360
2361         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2362                 if (rt->dst.dev->ifindex != ifindex)
2363                         continue;
2364                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2365                         continue;
2366                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2367                         continue;
2368                 dst_hold(&rt->dst);
2369                 break;
2370         }
2371 out:
2372         read_unlock_bh(&table->tb6_lock);
2373         return rt;
2374 }
2375
2376 static struct rt6_info *rt6_add_route_info(struct net *net,
2377                                            const struct in6_addr *prefix, int prefixlen,
2378                                            const struct in6_addr *gwaddr,
2379                                            struct net_device *dev,
2380                                            unsigned int pref)
2381 {
2382         struct fib6_config cfg = {
2383                 .fc_metric      = IP6_RT_PRIO_USER,
2384                 .fc_ifindex     = dev->ifindex,
2385                 .fc_dst_len     = prefixlen,
2386                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2387                                   RTF_UP | RTF_PREF(pref),
2388                 .fc_nlinfo.portid = 0,
2389                 .fc_nlinfo.nlh = NULL,
2390                 .fc_nlinfo.nl_net = net,
2391         };
2392
2393         cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
2394         cfg.fc_dst = *prefix;
2395         cfg.fc_gateway = *gwaddr;
2396
2397         /* We should treat it as a default route if prefix length is 0. */
2398         if (!prefixlen)
2399                 cfg.fc_flags |= RTF_DEFAULT;
2400
2401         ip6_route_add(&cfg);
2402
2403         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
2404 }
2405 #endif
2406
2407 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2408 {
2409         u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
2410         struct rt6_info *rt;
2411         struct fib6_table *table;
2412
2413         table = fib6_get_table(dev_net(dev), tb_id);
2414         if (!table)
2415                 return NULL;
2416
2417         read_lock_bh(&table->tb6_lock);
2418         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2419                 if (dev == rt->dst.dev &&
2420                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2421                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2422                         break;
2423         }
2424         if (rt)
2425                 dst_hold(&rt->dst);
2426         read_unlock_bh(&table->tb6_lock);
2427         return rt;
2428 }
2429
2430 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2431                                      struct net_device *dev,
2432                                      unsigned int pref)
2433 {
2434         struct fib6_config cfg = {
2435                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2436                 .fc_metric      = IP6_RT_PRIO_USER,
2437                 .fc_ifindex     = dev->ifindex,
2438                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2439                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2440                 .fc_nlinfo.portid = 0,
2441                 .fc_nlinfo.nlh = NULL,
2442                 .fc_nlinfo.nl_net = dev_net(dev),
2443         };
2444
2445         cfg.fc_gateway = *gwaddr;
2446
2447         if (!ip6_route_add(&cfg)) {
2448                 struct fib6_table *table;
2449
2450                 table = fib6_get_table(dev_net(dev), cfg.fc_table);
2451                 if (table)
2452                         table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
2453         }
2454
2455         return rt6_get_dflt_router(gwaddr, dev);
2456 }
2457
2458 static void __rt6_purge_dflt_routers(struct fib6_table *table)
2459 {
2460         struct rt6_info *rt;
2461
2462 restart:
2463         read_lock_bh(&table->tb6_lock);
2464         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2465                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2466                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2467                         dst_hold(&rt->dst);
2468                         read_unlock_bh(&table->tb6_lock);
2469                         ip6_del_rt(rt);
2470                         goto restart;
2471                 }
2472         }
2473         read_unlock_bh(&table->tb6_lock);
2474
2475         table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
2476 }
2477
2478 void rt6_purge_dflt_routers(struct net *net)
2479 {
2480         struct fib6_table *table;
2481         struct hlist_head *head;
2482         unsigned int h;
2483
2484         rcu_read_lock();
2485
2486         for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
2487                 head = &net->ipv6.fib_table_hash[h];
2488                 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
2489                         if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
2490                                 __rt6_purge_dflt_routers(table);
2491                 }
2492         }
2493
2494         rcu_read_unlock();
2495 }
2496
2497 static void rtmsg_to_fib6_config(struct net *net,
2498                                  struct in6_rtmsg *rtmsg,
2499                                  struct fib6_config *cfg)
2500 {
2501         memset(cfg, 0, sizeof(*cfg));
2502
2503         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2504                          : RT6_TABLE_MAIN;
2505         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2506         cfg->fc_metric = rtmsg->rtmsg_metric;
2507         cfg->fc_expires = rtmsg->rtmsg_info;
2508         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2509         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2510         cfg->fc_flags = rtmsg->rtmsg_flags;
2511
2512         cfg->fc_nlinfo.nl_net = net;
2513
2514         cfg->fc_dst = rtmsg->rtmsg_dst;
2515         cfg->fc_src = rtmsg->rtmsg_src;
2516         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2517 }
2518
2519 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2520 {
2521         struct fib6_config cfg;
2522         struct in6_rtmsg rtmsg;
2523         int err;
2524
2525         switch (cmd) {
2526         case SIOCADDRT:         /* Add a route */
2527         case SIOCDELRT:         /* Delete a route */
2528                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2529                         return -EPERM;
2530                 err = copy_from_user(&rtmsg, arg,
2531                                      sizeof(struct in6_rtmsg));
2532                 if (err)
2533                         return -EFAULT;
2534
2535                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2536
2537                 rtnl_lock();
2538                 switch (cmd) {
2539                 case SIOCADDRT:
2540                         err = ip6_route_add(&cfg);
2541                         break;
2542                 case SIOCDELRT:
2543                         err = ip6_route_del(&cfg);
2544                         break;
2545                 default:
2546                         err = -EINVAL;
2547                 }
2548                 rtnl_unlock();
2549
2550                 return err;
2551         }
2552
2553         return -EINVAL;
2554 }
2555
2556 /*
2557  *      Drop the packet on the floor
2558  */
2559
2560 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2561 {
2562         int type;
2563         struct dst_entry *dst = skb_dst(skb);
2564         switch (ipstats_mib_noroutes) {
2565         case IPSTATS_MIB_INNOROUTES:
2566                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2567                 if (type == IPV6_ADDR_ANY) {
2568                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2569                                       IPSTATS_MIB_INADDRERRORS);
2570                         break;
2571                 }
2572                 /* FALLTHROUGH */
2573         case IPSTATS_MIB_OUTNOROUTES:
2574                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2575                               ipstats_mib_noroutes);
2576                 break;
2577         }
2578         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2579         kfree_skb(skb);
2580         return 0;
2581 }
2582
2583 static int ip6_pkt_discard(struct sk_buff *skb)
2584 {
2585         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2586 }
2587
2588 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2589 {
2590         skb->dev = skb_dst(skb)->dev;
2591         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2592 }
2593
2594 static int ip6_pkt_prohibit(struct sk_buff *skb)
2595 {
2596         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2597 }
2598
2599 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2600 {
2601         skb->dev = skb_dst(skb)->dev;
2602         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2603 }
2604
2605 /*
2606  *      Allocate a dst for local (unicast / anycast) address.
2607  */
2608
2609 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2610                                     const struct in6_addr *addr,
2611                                     bool anycast)
2612 {
2613         u32 tb_id;
2614         struct net *net = dev_net(idev->dev);
2615         struct net_device *dev = net->loopback_dev;
2616         struct rt6_info *rt;
2617
2618         /* use L3 Master device as loopback for host routes if device
2619          * is enslaved and address is not link local or multicast
2620          */
2621         if (!rt6_need_strict(addr))
2622                 dev = l3mdev_master_dev_rcu(idev->dev) ? : dev;
2623
2624         rt = ip6_dst_alloc(net, dev, DST_NOCOUNT);
2625         if (!rt)
2626                 return ERR_PTR(-ENOMEM);
2627
2628         in6_dev_hold(idev);
2629
2630         rt->dst.flags |= DST_HOST;
2631         rt->dst.input = ip6_input;
2632         rt->dst.output = ip6_output;
2633         rt->rt6i_idev = idev;
2634
2635         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2636         if (anycast)
2637                 rt->rt6i_flags |= RTF_ANYCAST;
2638         else
2639                 rt->rt6i_flags |= RTF_LOCAL;
2640
2641         rt->rt6i_gateway  = *addr;
2642         rt->rt6i_dst.addr = *addr;
2643         rt->rt6i_dst.plen = 128;
2644         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2645         rt->rt6i_table = fib6_get_table(net, tb_id);
2646         rt->dst.flags |= DST_NOCACHE;
2647
2648         atomic_set(&rt->dst.__refcnt, 1);
2649
2650         return rt;
2651 }
2652
2653 /* remove deleted ip from prefsrc entries */
2654 struct arg_dev_net_ip {
2655         struct net_device *dev;
2656         struct net *net;
2657         struct in6_addr *addr;
2658 };
2659
2660 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2661 {
2662         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2663         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2664         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2665
2666         if (((void *)rt->dst.dev == dev || !dev) &&
2667             rt != net->ipv6.ip6_null_entry &&
2668             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2669                 /* remove prefsrc entry */
2670                 rt->rt6i_prefsrc.plen = 0;
2671         }
2672         return 0;
2673 }
2674
2675 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2676 {
2677         struct net *net = dev_net(ifp->idev->dev);
2678         struct arg_dev_net_ip adni = {
2679                 .dev = ifp->idev->dev,
2680                 .net = net,
2681                 .addr = &ifp->addr,
2682         };
2683         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2684 }
2685
2686 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2687 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2688
2689 /* Remove routers and update dst entries when gateway turn into host. */
2690 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2691 {
2692         struct in6_addr *gateway = (struct in6_addr *)arg;
2693
2694         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2695              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2696              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2697                 return -1;
2698         }
2699         return 0;
2700 }
2701
2702 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2703 {
2704         fib6_clean_all(net, fib6_clean_tohost, gateway);
2705 }
2706
2707 struct arg_dev_net {
2708         struct net_device *dev;
2709         struct net *net;
2710 };
2711
2712 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2713 {
2714         const struct arg_dev_net *adn = arg;
2715         const struct net_device *dev = adn->dev;
2716
2717         if ((rt->dst.dev == dev || !dev) &&
2718             rt != adn->net->ipv6.ip6_null_entry)
2719                 return -1;
2720
2721         return 0;
2722 }
2723
2724 void rt6_ifdown(struct net *net, struct net_device *dev)
2725 {
2726         struct arg_dev_net adn = {
2727                 .dev = dev,
2728                 .net = net,
2729         };
2730
2731         fib6_clean_all(net, fib6_ifdown, &adn);
2732         icmp6_clean_all(fib6_ifdown, &adn);
2733         if (dev)
2734                 rt6_uncached_list_flush_dev(net, dev);
2735 }
2736
2737 struct rt6_mtu_change_arg {
2738         struct net_device *dev;
2739         unsigned int mtu;
2740 };
2741
2742 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2743 {
2744         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2745         struct inet6_dev *idev;
2746
2747         /* In IPv6 pmtu discovery is not optional,
2748            so that RTAX_MTU lock cannot disable it.
2749            We still use this lock to block changes
2750            caused by addrconf/ndisc.
2751         */
2752
2753         idev = __in6_dev_get(arg->dev);
2754         if (!idev)
2755                 return 0;
2756
2757         /* For administrative MTU increase, there is no way to discover
2758            IPv6 PMTU increase, so PMTU increase should be updated here.
2759            Since RFC 1981 doesn't include administrative MTU increase
2760            update PMTU increase is a MUST. (i.e. jumbo frame)
2761          */
2762         /*
2763            If new MTU is less than route PMTU, this new MTU will be the
2764            lowest MTU in the path, update the route PMTU to reflect PMTU
2765            decreases; if new MTU is greater than route PMTU, and the
2766            old MTU is the lowest MTU in the path, update the route PMTU
2767            to reflect the increase. In this case if the other nodes' MTU
2768            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2769            PMTU discouvery.
2770          */
2771         if (rt->dst.dev == arg->dev &&
2772             dst_metric_raw(&rt->dst, RTAX_MTU) &&
2773             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2774                 if (rt->rt6i_flags & RTF_CACHE) {
2775                         /* For RTF_CACHE with rt6i_pmtu == 0
2776                          * (i.e. a redirected route),
2777                          * the metrics of its rt->dst.from has already
2778                          * been updated.
2779                          */
2780                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2781                                 rt->rt6i_pmtu = arg->mtu;
2782                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2783                            (dst_mtu(&rt->dst) < arg->mtu &&
2784                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2785                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2786                 }
2787         }
2788         return 0;
2789 }
2790
2791 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2792 {
2793         struct rt6_mtu_change_arg arg = {
2794                 .dev = dev,
2795                 .mtu = mtu,
2796         };
2797
2798         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2799 }
2800
2801 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2802         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2803         [RTA_OIF]               = { .type = NLA_U32 },
2804         [RTA_IIF]               = { .type = NLA_U32 },
2805         [RTA_PRIORITY]          = { .type = NLA_U32 },
2806         [RTA_METRICS]           = { .type = NLA_NESTED },
2807         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2808         [RTA_PREF]              = { .type = NLA_U8 },
2809         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2810         [RTA_ENCAP]             = { .type = NLA_NESTED },
2811         [RTA_EXPIRES]           = { .type = NLA_U32 },
2812         [RTA_UID]               = { .type = NLA_U32 },
2813 };
2814
2815 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2816                               struct fib6_config *cfg)
2817 {
2818         struct rtmsg *rtm;
2819         struct nlattr *tb[RTA_MAX+1];
2820         unsigned int pref;
2821         int err;
2822
2823         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2824         if (err < 0)
2825                 goto errout;
2826
2827         err = -EINVAL;
2828         rtm = nlmsg_data(nlh);
2829         memset(cfg, 0, sizeof(*cfg));
2830
2831         cfg->fc_table = rtm->rtm_table;
2832         cfg->fc_dst_len = rtm->rtm_dst_len;
2833         cfg->fc_src_len = rtm->rtm_src_len;
2834         cfg->fc_flags = RTF_UP;
2835         cfg->fc_protocol = rtm->rtm_protocol;
2836         cfg->fc_type = rtm->rtm_type;
2837
2838         if (rtm->rtm_type == RTN_UNREACHABLE ||
2839             rtm->rtm_type == RTN_BLACKHOLE ||
2840             rtm->rtm_type == RTN_PROHIBIT ||
2841             rtm->rtm_type == RTN_THROW)
2842                 cfg->fc_flags |= RTF_REJECT;
2843
2844         if (rtm->rtm_type == RTN_LOCAL)
2845                 cfg->fc_flags |= RTF_LOCAL;
2846
2847         if (rtm->rtm_flags & RTM_F_CLONED)
2848                 cfg->fc_flags |= RTF_CACHE;
2849
2850         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2851         cfg->fc_nlinfo.nlh = nlh;
2852         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2853
2854         if (tb[RTA_GATEWAY]) {
2855                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2856                 cfg->fc_flags |= RTF_GATEWAY;
2857         }
2858
2859         if (tb[RTA_DST]) {
2860                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2861
2862                 if (nla_len(tb[RTA_DST]) < plen)
2863                         goto errout;
2864
2865                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2866         }
2867
2868         if (tb[RTA_SRC]) {
2869                 int plen = (rtm->rtm_src_len + 7) >> 3;
2870
2871                 if (nla_len(tb[RTA_SRC]) < plen)
2872                         goto errout;
2873
2874                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2875         }
2876
2877         if (tb[RTA_PREFSRC])
2878                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2879
2880         if (tb[RTA_OIF])
2881                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2882
2883         if (tb[RTA_PRIORITY])
2884                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2885
2886         if (tb[RTA_METRICS]) {
2887                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2888                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2889         }
2890
2891         if (tb[RTA_TABLE])
2892                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2893
2894         if (tb[RTA_MULTIPATH]) {
2895                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2896                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2897         }
2898
2899         if (tb[RTA_PREF]) {
2900                 pref = nla_get_u8(tb[RTA_PREF]);
2901                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2902                     pref != ICMPV6_ROUTER_PREF_HIGH)
2903                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2904                 cfg->fc_flags |= RTF_PREF(pref);
2905         }
2906
2907         if (tb[RTA_ENCAP])
2908                 cfg->fc_encap = tb[RTA_ENCAP];
2909
2910         if (tb[RTA_ENCAP_TYPE])
2911                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2912
2913         if (tb[RTA_EXPIRES]) {
2914                 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
2915
2916                 if (addrconf_finite_timeout(timeout)) {
2917                         cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
2918                         cfg->fc_flags |= RTF_EXPIRES;
2919                 }
2920         }
2921
2922         err = 0;
2923 errout:
2924         return err;
2925 }
2926
2927 struct rt6_nh {
2928         struct rt6_info *rt6_info;
2929         struct fib6_config r_cfg;
2930         struct mx6_config mxc;
2931         struct list_head next;
2932 };
2933
2934 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2935 {
2936         struct rt6_nh *nh;
2937
2938         list_for_each_entry(nh, rt6_nh_list, next) {
2939                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2940                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2941                         nh->r_cfg.fc_ifindex);
2942         }
2943 }
2944
2945 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2946                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2947 {
2948         struct rt6_nh *nh;
2949         struct rt6_info *rtnh;
2950         int err = -EEXIST;
2951
2952         list_for_each_entry(nh, rt6_nh_list, next) {
2953                 /* check if rt6_info already exists */
2954                 rtnh = nh->rt6_info;
2955
2956                 if (rtnh->dst.dev == rt->dst.dev &&
2957                     rtnh->rt6i_idev == rt->rt6i_idev &&
2958                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2959                                     &rt->rt6i_gateway))
2960                         return err;
2961         }
2962
2963         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2964         if (!nh)
2965                 return -ENOMEM;
2966         nh->rt6_info = rt;
2967         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2968         if (err) {
2969                 kfree(nh);
2970                 return err;
2971         }
2972         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2973         list_add_tail(&nh->next, rt6_nh_list);
2974
2975         return 0;
2976 }
2977
2978 static int ip6_route_multipath_add(struct fib6_config *cfg)
2979 {
2980         struct fib6_config r_cfg;
2981         struct rtnexthop *rtnh;
2982         struct rt6_info *rt;
2983         struct rt6_nh *err_nh;
2984         struct rt6_nh *nh, *nh_safe;
2985         int remaining;
2986         int attrlen;
2987         int err = 1;
2988         int nhn = 0;
2989         int replace = (cfg->fc_nlinfo.nlh &&
2990                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2991         LIST_HEAD(rt6_nh_list);
2992
2993         remaining = cfg->fc_mp_len;
2994         rtnh = (struct rtnexthop *)cfg->fc_mp;
2995
2996         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2997          * rt6_info structs per nexthop
2998          */
2999         while (rtnh_ok(rtnh, remaining)) {
3000                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3001                 if (rtnh->rtnh_ifindex)
3002                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3003
3004                 attrlen = rtnh_attrlen(rtnh);
3005                 if (attrlen > 0) {
3006                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3007
3008                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3009                         if (nla) {
3010                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
3011                                 r_cfg.fc_flags |= RTF_GATEWAY;
3012                         }
3013                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
3014                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
3015                         if (nla)
3016                                 r_cfg.fc_encap_type = nla_get_u16(nla);
3017                 }
3018
3019                 rt = ip6_route_info_create(&r_cfg);
3020                 if (IS_ERR(rt)) {
3021                         err = PTR_ERR(rt);
3022                         rt = NULL;
3023                         goto cleanup;
3024                 }
3025
3026                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
3027                 if (err) {
3028                         dst_free(&rt->dst);
3029                         goto cleanup;
3030                 }
3031
3032                 rtnh = rtnh_next(rtnh, &remaining);
3033         }
3034
3035         err_nh = NULL;
3036         list_for_each_entry(nh, &rt6_nh_list, next) {
3037                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
3038                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
3039                 nh->rt6_info = NULL;
3040                 if (err) {
3041                         if (replace && nhn)
3042                                 ip6_print_replace_route_err(&rt6_nh_list);
3043                         err_nh = nh;
3044                         goto add_errout;
3045                 }
3046
3047                 /* Because each route is added like a single route we remove
3048                  * these flags after the first nexthop: if there is a collision,
3049                  * we have already failed to add the first nexthop:
3050                  * fib6_add_rt2node() has rejected it; when replacing, old
3051                  * nexthops have been replaced by first new, the rest should
3052                  * be added to it.
3053                  */
3054                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
3055                                                      NLM_F_REPLACE);
3056                 nhn++;
3057         }
3058
3059         goto cleanup;
3060
3061 add_errout:
3062         /* Delete routes that were already added */
3063         list_for_each_entry(nh, &rt6_nh_list, next) {
3064                 if (err_nh == nh)
3065                         break;
3066                 ip6_route_del(&nh->r_cfg);
3067         }
3068
3069 cleanup:
3070         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
3071                 if (nh->rt6_info)
3072                         dst_free(&nh->rt6_info->dst);
3073                 kfree(nh->mxc.mx);
3074                 list_del(&nh->next);
3075                 kfree(nh);
3076         }
3077
3078         return err;
3079 }
3080
3081 static int ip6_route_multipath_del(struct fib6_config *cfg)
3082 {
3083         struct fib6_config r_cfg;
3084         struct rtnexthop *rtnh;
3085         int remaining;
3086         int attrlen;
3087         int err = 1, last_err = 0;
3088
3089         remaining = cfg->fc_mp_len;
3090         rtnh = (struct rtnexthop *)cfg->fc_mp;
3091
3092         /* Parse a Multipath Entry */
3093         while (rtnh_ok(rtnh, remaining)) {
3094                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3095                 if (rtnh->rtnh_ifindex)
3096                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3097
3098                 attrlen = rtnh_attrlen(rtnh);
3099                 if (attrlen > 0) {
3100                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3101
3102                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3103                         if (nla) {
3104                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3105                                 r_cfg.fc_flags |= RTF_GATEWAY;
3106                         }
3107                 }
3108                 err = ip6_route_del(&r_cfg);
3109                 if (err)
3110                         last_err = err;
3111
3112                 rtnh = rtnh_next(rtnh, &remaining);
3113         }
3114
3115         return last_err;
3116 }
3117
3118 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3119 {
3120         struct fib6_config cfg;
3121         int err;
3122
3123         err = rtm_to_fib6_config(skb, nlh, &cfg);
3124         if (err < 0)
3125                 return err;
3126
3127         if (cfg.fc_mp)
3128                 return ip6_route_multipath_del(&cfg);
3129         else
3130                 return ip6_route_del(&cfg);
3131 }
3132
3133 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3134 {
3135         struct fib6_config cfg;
3136         int err;
3137
3138         err = rtm_to_fib6_config(skb, nlh, &cfg);
3139         if (err < 0)
3140                 return err;
3141
3142         if (cfg.fc_mp)
3143                 return ip6_route_multipath_add(&cfg);
3144         else
3145                 return ip6_route_add(&cfg);
3146 }
3147
3148 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3149 {
3150         return NLMSG_ALIGN(sizeof(struct rtmsg))
3151                + nla_total_size(16) /* RTA_SRC */
3152                + nla_total_size(16) /* RTA_DST */
3153                + nla_total_size(16) /* RTA_GATEWAY */
3154                + nla_total_size(16) /* RTA_PREFSRC */
3155                + nla_total_size(4) /* RTA_TABLE */
3156                + nla_total_size(4) /* RTA_IIF */
3157                + nla_total_size(4) /* RTA_OIF */
3158                + nla_total_size(4) /* RTA_PRIORITY */
3159                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3160                + nla_total_size(sizeof(struct rta_cacheinfo))
3161                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3162                + nla_total_size(1) /* RTA_PREF */
3163                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3164 }
3165
3166 static int rt6_fill_node(struct net *net,
3167                          struct sk_buff *skb, struct rt6_info *rt,
3168                          struct in6_addr *dst, struct in6_addr *src,
3169                          int iif, int type, u32 portid, u32 seq,
3170                          int prefix, int nowait, unsigned int flags)
3171 {
3172         u32 metrics[RTAX_MAX];
3173         struct rtmsg *rtm;
3174         struct nlmsghdr *nlh;
3175         long expires;
3176         u32 table;
3177
3178         if (prefix) {   /* user wants prefix routes only */
3179                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3180                         /* success since this is not a prefix route */
3181                         return 1;
3182                 }
3183         }
3184
3185         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3186         if (!nlh)
3187                 return -EMSGSIZE;
3188
3189         rtm = nlmsg_data(nlh);
3190         rtm->rtm_family = AF_INET6;
3191         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3192         rtm->rtm_src_len = rt->rt6i_src.plen;
3193         rtm->rtm_tos = 0;
3194         if (rt->rt6i_table)
3195                 table = rt->rt6i_table->tb6_id;
3196         else
3197                 table = RT6_TABLE_UNSPEC;
3198         rtm->rtm_table = table;
3199         if (nla_put_u32(skb, RTA_TABLE, table))
3200                 goto nla_put_failure;
3201         if (rt->rt6i_flags & RTF_REJECT) {
3202                 switch (rt->dst.error) {
3203                 case -EINVAL:
3204                         rtm->rtm_type = RTN_BLACKHOLE;
3205                         break;
3206                 case -EACCES:
3207                         rtm->rtm_type = RTN_PROHIBIT;
3208                         break;
3209                 case -EAGAIN:
3210                         rtm->rtm_type = RTN_THROW;
3211                         break;
3212                 default:
3213                         rtm->rtm_type = RTN_UNREACHABLE;
3214                         break;
3215                 }
3216         }
3217         else if (rt->rt6i_flags & RTF_LOCAL)
3218                 rtm->rtm_type = RTN_LOCAL;
3219         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3220                 rtm->rtm_type = RTN_LOCAL;
3221         else
3222                 rtm->rtm_type = RTN_UNICAST;
3223         rtm->rtm_flags = 0;
3224         if (!netif_carrier_ok(rt->dst.dev)) {
3225                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3226                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3227                         rtm->rtm_flags |= RTNH_F_DEAD;
3228         }
3229         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3230         rtm->rtm_protocol = rt->rt6i_protocol;
3231         if (rt->rt6i_flags & RTF_DYNAMIC)
3232                 rtm->rtm_protocol = RTPROT_REDIRECT;
3233         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3234                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3235                         rtm->rtm_protocol = RTPROT_RA;
3236                 else
3237                         rtm->rtm_protocol = RTPROT_KERNEL;
3238         }
3239
3240         if (rt->rt6i_flags & RTF_CACHE)
3241                 rtm->rtm_flags |= RTM_F_CLONED;
3242
3243         if (dst) {
3244                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3245                         goto nla_put_failure;
3246                 rtm->rtm_dst_len = 128;
3247         } else if (rtm->rtm_dst_len)
3248                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3249                         goto nla_put_failure;
3250 #ifdef CONFIG_IPV6_SUBTREES
3251         if (src) {
3252                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3253                         goto nla_put_failure;
3254                 rtm->rtm_src_len = 128;
3255         } else if (rtm->rtm_src_len &&
3256                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3257                 goto nla_put_failure;
3258 #endif
3259         if (iif) {
3260 #ifdef CONFIG_IPV6_MROUTE
3261                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3262                         int err = ip6mr_get_route(net, skb, rtm, nowait,
3263                                                   portid);
3264
3265                         if (err <= 0) {
3266                                 if (!nowait) {
3267                                         if (err == 0)
3268                                                 return 0;
3269                                         goto nla_put_failure;
3270                                 } else {
3271                                         if (err == -EMSGSIZE)
3272                                                 goto nla_put_failure;
3273                                 }
3274                         }
3275                 } else
3276 #endif
3277                         if (nla_put_u32(skb, RTA_IIF, iif))
3278                                 goto nla_put_failure;
3279         } else if (dst) {
3280                 struct in6_addr saddr_buf;
3281                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3282                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3283                         goto nla_put_failure;
3284         }
3285
3286         if (rt->rt6i_prefsrc.plen) {
3287                 struct in6_addr saddr_buf;
3288                 saddr_buf = rt->rt6i_prefsrc.addr;
3289                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3290                         goto nla_put_failure;
3291         }
3292
3293         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3294         if (rt->rt6i_pmtu)
3295                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3296         if (rtnetlink_put_metrics(skb, metrics) < 0)
3297                 goto nla_put_failure;
3298
3299         if (rt->rt6i_flags & RTF_GATEWAY) {
3300                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3301                         goto nla_put_failure;
3302         }
3303
3304         if (rt->dst.dev &&
3305             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3306                 goto nla_put_failure;
3307         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3308                 goto nla_put_failure;
3309
3310         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3311
3312         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3313                 goto nla_put_failure;
3314
3315         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3316                 goto nla_put_failure;
3317
3318         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3319
3320         nlmsg_end(skb, nlh);
3321         return 0;
3322
3323 nla_put_failure:
3324         nlmsg_cancel(skb, nlh);
3325         return -EMSGSIZE;
3326 }
3327
3328 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3329 {
3330         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3331         int prefix;
3332
3333         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3334                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3335                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3336         } else
3337                 prefix = 0;
3338
3339         return rt6_fill_node(arg->net,
3340                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3341                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3342                      prefix, 0, NLM_F_MULTI);
3343 }
3344
3345 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3346 {
3347         struct net *net = sock_net(in_skb->sk);
3348         struct nlattr *tb[RTA_MAX+1];
3349         struct rt6_info *rt;
3350         struct sk_buff *skb;
3351         struct rtmsg *rtm;
3352         struct flowi6 fl6;
3353         int err, iif = 0, oif = 0;
3354
3355         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3356         if (err < 0)
3357                 goto errout;
3358
3359         err = -EINVAL;
3360         memset(&fl6, 0, sizeof(fl6));
3361         rtm = nlmsg_data(nlh);
3362         fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
3363
3364         if (tb[RTA_SRC]) {
3365                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3366                         goto errout;
3367
3368                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3369         }
3370
3371         if (tb[RTA_DST]) {
3372                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3373                         goto errout;
3374
3375                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3376         }
3377
3378         if (tb[RTA_IIF])
3379                 iif = nla_get_u32(tb[RTA_IIF]);
3380
3381         if (tb[RTA_OIF])
3382                 oif = nla_get_u32(tb[RTA_OIF]);
3383
3384         if (tb[RTA_MARK])
3385                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3386
3387         if (tb[RTA_UID])
3388                 fl6.flowi6_uid = make_kuid(current_user_ns(),
3389                                            nla_get_u32(tb[RTA_UID]));
3390         else
3391                 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
3392
3393         if (iif) {
3394                 struct net_device *dev;
3395                 int flags = 0;
3396
3397                 dev = __dev_get_by_index(net, iif);
3398                 if (!dev) {
3399                         err = -ENODEV;
3400                         goto errout;
3401                 }
3402
3403                 fl6.flowi6_iif = iif;
3404
3405                 if (!ipv6_addr_any(&fl6.saddr))
3406                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3407
3408                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3409                                                                flags);
3410         } else {
3411                 fl6.flowi6_oif = oif;
3412
3413                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3414         }
3415
3416         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3417         if (!skb) {
3418                 ip6_rt_put(rt);
3419                 err = -ENOBUFS;
3420                 goto errout;
3421         }
3422
3423         /* Reserve room for dummy headers, this skb can pass
3424            through good chunk of routing engine.
3425          */
3426         skb_reset_mac_header(skb);
3427         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3428
3429         skb_dst_set(skb, &rt->dst);
3430
3431         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3432                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3433                             nlh->nlmsg_seq, 0, 0, 0);
3434         if (err < 0) {
3435                 kfree_skb(skb);
3436                 goto errout;
3437         }
3438
3439         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3440 errout:
3441         return err;
3442 }
3443
3444 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3445                      unsigned int nlm_flags)
3446 {
3447         struct sk_buff *skb;
3448         struct net *net = info->nl_net;
3449         u32 seq;
3450         int err;
3451
3452         err = -ENOBUFS;
3453         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3454
3455         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3456         if (!skb)
3457                 goto errout;
3458
3459         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3460                                 event, info->portid, seq, 0, 0, nlm_flags);
3461         if (err < 0) {
3462                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3463                 WARN_ON(err == -EMSGSIZE);
3464                 kfree_skb(skb);
3465                 goto errout;
3466         }
3467         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3468                     info->nlh, gfp_any());
3469         return;
3470 errout:
3471         if (err < 0)
3472                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3473 }
3474
3475 static int ip6_route_dev_notify(struct notifier_block *this,
3476                                 unsigned long event, void *ptr)
3477 {
3478         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3479         struct net *net = dev_net(dev);
3480
3481         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3482                 net->ipv6.ip6_null_entry->dst.dev = dev;
3483                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3484 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3485                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3486                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3487                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3488                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3489 #endif
3490         }
3491
3492         return NOTIFY_OK;
3493 }
3494
3495 /*
3496  *      /proc
3497  */
3498
3499 #ifdef CONFIG_PROC_FS
3500
3501 static const struct file_operations ipv6_route_proc_fops = {
3502         .owner          = THIS_MODULE,
3503         .open           = ipv6_route_open,
3504         .read           = seq_read,
3505         .llseek         = seq_lseek,
3506         .release        = seq_release_net,
3507 };
3508
3509 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3510 {
3511         struct net *net = (struct net *)seq->private;
3512         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3513                    net->ipv6.rt6_stats->fib_nodes,
3514                    net->ipv6.rt6_stats->fib_route_nodes,
3515                    net->ipv6.rt6_stats->fib_rt_alloc,
3516                    net->ipv6.rt6_stats->fib_rt_entries,
3517                    net->ipv6.rt6_stats->fib_rt_cache,
3518                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3519                    net->ipv6.rt6_stats->fib_discarded_routes);
3520
3521         return 0;
3522 }
3523
3524 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3525 {
3526         return single_open_net(inode, file, rt6_stats_seq_show);
3527 }
3528
3529 static const struct file_operations rt6_stats_seq_fops = {
3530         .owner   = THIS_MODULE,
3531         .open    = rt6_stats_seq_open,
3532         .read    = seq_read,
3533         .llseek  = seq_lseek,
3534         .release = single_release_net,
3535 };
3536 #endif  /* CONFIG_PROC_FS */
3537
3538 #ifdef CONFIG_SYSCTL
3539
3540 static
3541 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3542                               void __user *buffer, size_t *lenp, loff_t *ppos)
3543 {
3544         struct net *net;
3545         int delay;
3546         if (!write)
3547                 return -EINVAL;
3548
3549         net = (struct net *)ctl->extra1;
3550         delay = net->ipv6.sysctl.flush_delay;
3551         proc_dointvec(ctl, write, buffer, lenp, ppos);
3552         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3553         return 0;
3554 }
3555
3556 struct ctl_table ipv6_route_table_template[] = {
3557         {
3558                 .procname       =       "flush",
3559                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3560                 .maxlen         =       sizeof(int),
3561                 .mode           =       0200,
3562                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3563         },
3564         {
3565                 .procname       =       "gc_thresh",
3566                 .data           =       &ip6_dst_ops_template.gc_thresh,
3567                 .maxlen         =       sizeof(int),
3568                 .mode           =       0644,
3569                 .proc_handler   =       proc_dointvec,
3570         },
3571         {
3572                 .procname       =       "max_size",
3573                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3574                 .maxlen         =       sizeof(int),
3575                 .mode           =       0644,
3576                 .proc_handler   =       proc_dointvec,
3577         },
3578         {
3579                 .procname       =       "gc_min_interval",
3580                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3581                 .maxlen         =       sizeof(int),
3582                 .mode           =       0644,
3583                 .proc_handler   =       proc_dointvec_jiffies,
3584         },
3585         {
3586                 .procname       =       "gc_timeout",
3587                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3588                 .maxlen         =       sizeof(int),
3589                 .mode           =       0644,
3590                 .proc_handler   =       proc_dointvec_jiffies,
3591         },
3592         {
3593                 .procname       =       "gc_interval",
3594                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3595                 .maxlen         =       sizeof(int),
3596                 .mode           =       0644,
3597                 .proc_handler   =       proc_dointvec_jiffies,
3598         },
3599         {
3600                 .procname       =       "gc_elasticity",
3601                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3602                 .maxlen         =       sizeof(int),
3603                 .mode           =       0644,
3604                 .proc_handler   =       proc_dointvec,
3605         },
3606         {
3607                 .procname       =       "mtu_expires",
3608                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3609                 .maxlen         =       sizeof(int),
3610                 .mode           =       0644,
3611                 .proc_handler   =       proc_dointvec_jiffies,
3612         },
3613         {
3614                 .procname       =       "min_adv_mss",
3615                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3616                 .maxlen         =       sizeof(int),
3617                 .mode           =       0644,
3618                 .proc_handler   =       proc_dointvec,
3619         },
3620         {
3621                 .procname       =       "gc_min_interval_ms",
3622                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3623                 .maxlen         =       sizeof(int),
3624                 .mode           =       0644,
3625                 .proc_handler   =       proc_dointvec_ms_jiffies,
3626         },
3627         { }
3628 };
3629
3630 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3631 {
3632         struct ctl_table *table;
3633
3634         table = kmemdup(ipv6_route_table_template,
3635                         sizeof(ipv6_route_table_template),
3636                         GFP_KERNEL);
3637
3638         if (table) {
3639                 table[0].data = &net->ipv6.sysctl.flush_delay;
3640                 table[0].extra1 = net;
3641                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3642                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3643                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3644                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3645                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3646                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3647                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3648                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3649                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3650
3651                 /* Don't export sysctls to unprivileged users */
3652                 if (net->user_ns != &init_user_ns)
3653                         table[0].procname = NULL;
3654         }
3655
3656         return table;
3657 }
3658 #endif
3659
3660 static int __net_init ip6_route_net_init(struct net *net)
3661 {
3662         int ret = -ENOMEM;
3663
3664         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3665                sizeof(net->ipv6.ip6_dst_ops));
3666
3667         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3668                 goto out_ip6_dst_ops;
3669
3670         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3671                                            sizeof(*net->ipv6.ip6_null_entry),
3672                                            GFP_KERNEL);
3673         if (!net->ipv6.ip6_null_entry)
3674                 goto out_ip6_dst_entries;
3675         net->ipv6.ip6_null_entry->dst.path =
3676                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3677         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3678         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3679                          ip6_template_metrics, true);
3680
3681 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3682         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3683                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3684                                                GFP_KERNEL);
3685         if (!net->ipv6.ip6_prohibit_entry)
3686                 goto out_ip6_null_entry;
3687         net->ipv6.ip6_prohibit_entry->dst.path =
3688                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3689         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3690         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3691                          ip6_template_metrics, true);
3692
3693         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3694                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3695                                                GFP_KERNEL);
3696         if (!net->ipv6.ip6_blk_hole_entry)
3697                 goto out_ip6_prohibit_entry;
3698         net->ipv6.ip6_blk_hole_entry->dst.path =
3699                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3700         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3701         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3702                          ip6_template_metrics, true);
3703 #endif
3704
3705         net->ipv6.sysctl.flush_delay = 0;
3706         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3707         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3708         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3709         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3710         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3711         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3712         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3713
3714         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3715
3716         ret = 0;
3717 out:
3718         return ret;
3719
3720 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3721 out_ip6_prohibit_entry:
3722         kfree(net->ipv6.ip6_prohibit_entry);
3723 out_ip6_null_entry:
3724         kfree(net->ipv6.ip6_null_entry);
3725 #endif
3726 out_ip6_dst_entries:
3727         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3728 out_ip6_dst_ops:
3729         goto out;
3730 }
3731
3732 static void __net_exit ip6_route_net_exit(struct net *net)
3733 {
3734         kfree(net->ipv6.ip6_null_entry);
3735 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3736         kfree(net->ipv6.ip6_prohibit_entry);
3737         kfree(net->ipv6.ip6_blk_hole_entry);
3738 #endif
3739         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3740 }
3741
3742 static int __net_init ip6_route_net_init_late(struct net *net)
3743 {
3744 #ifdef CONFIG_PROC_FS
3745         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3746         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3747 #endif
3748         return 0;
3749 }
3750
3751 static void __net_exit ip6_route_net_exit_late(struct net *net)
3752 {
3753 #ifdef CONFIG_PROC_FS
3754         remove_proc_entry("ipv6_route", net->proc_net);
3755         remove_proc_entry("rt6_stats", net->proc_net);
3756 #endif
3757 }
3758
3759 static struct pernet_operations ip6_route_net_ops = {
3760         .init = ip6_route_net_init,
3761         .exit = ip6_route_net_exit,
3762 };
3763
3764 static int __net_init ipv6_inetpeer_init(struct net *net)
3765 {
3766         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3767
3768         if (!bp)
3769                 return -ENOMEM;
3770         inet_peer_base_init(bp);
3771         net->ipv6.peers = bp;
3772         return 0;
3773 }
3774
3775 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3776 {
3777         struct inet_peer_base *bp = net->ipv6.peers;
3778
3779         net->ipv6.peers = NULL;
3780         inetpeer_invalidate_tree(bp);
3781         kfree(bp);
3782 }
3783
3784 static struct pernet_operations ipv6_inetpeer_ops = {
3785         .init   =       ipv6_inetpeer_init,
3786         .exit   =       ipv6_inetpeer_exit,
3787 };
3788
3789 static struct pernet_operations ip6_route_net_late_ops = {
3790         .init = ip6_route_net_init_late,
3791         .exit = ip6_route_net_exit_late,
3792 };
3793
3794 static struct notifier_block ip6_route_dev_notifier = {
3795         .notifier_call = ip6_route_dev_notify,
3796         .priority = 0,
3797 };
3798
3799 int __init ip6_route_init(void)
3800 {
3801         int ret;
3802         int cpu;
3803
3804         ret = -ENOMEM;
3805         ip6_dst_ops_template.kmem_cachep =
3806                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3807                                   SLAB_HWCACHE_ALIGN, NULL);
3808         if (!ip6_dst_ops_template.kmem_cachep)
3809                 goto out;
3810
3811         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3812         if (ret)
3813                 goto out_kmem_cache;
3814
3815         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3816         if (ret)
3817                 goto out_dst_entries;
3818
3819         ret = register_pernet_subsys(&ip6_route_net_ops);
3820         if (ret)
3821                 goto out_register_inetpeer;
3822
3823         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3824
3825         /* Registering of the loopback is done before this portion of code,
3826          * the loopback reference in rt6_info will not be taken, do it
3827          * manually for init_net */
3828         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3829         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3830   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3831         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3832         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3833         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3834         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3835   #endif
3836         ret = fib6_init();
3837         if (ret)
3838                 goto out_register_subsys;
3839
3840         ret = xfrm6_init();
3841         if (ret)
3842                 goto out_fib6_init;
3843
3844         ret = fib6_rules_init();
3845         if (ret)
3846                 goto xfrm6_init;
3847
3848         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3849         if (ret)
3850                 goto fib6_rules_init;
3851
3852         ret = -ENOBUFS;
3853         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3854             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3855             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3856                 goto out_register_late_subsys;
3857
3858         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3859         if (ret)
3860                 goto out_register_late_subsys;
3861
3862         for_each_possible_cpu(cpu) {
3863                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3864
3865                 INIT_LIST_HEAD(&ul->head);
3866                 spin_lock_init(&ul->lock);
3867         }
3868
3869 out:
3870         return ret;
3871
3872 out_register_late_subsys:
3873         unregister_pernet_subsys(&ip6_route_net_late_ops);
3874 fib6_rules_init:
3875         fib6_rules_cleanup();
3876 xfrm6_init:
3877         xfrm6_fini();
3878 out_fib6_init:
3879         fib6_gc_cleanup();
3880 out_register_subsys:
3881         unregister_pernet_subsys(&ip6_route_net_ops);
3882 out_register_inetpeer:
3883         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3884 out_dst_entries:
3885         dst_entries_destroy(&ip6_dst_blackhole_ops);
3886 out_kmem_cache:
3887         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3888         goto out;
3889 }
3890
3891 void ip6_route_cleanup(void)
3892 {
3893         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3894         unregister_pernet_subsys(&ip6_route_net_late_ops);
3895         fib6_rules_cleanup();
3896         xfrm6_fini();
3897         fib6_gc_cleanup();
3898         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3899         unregister_pernet_subsys(&ip6_route_net_ops);
3900         dst_entries_destroy(&ip6_dst_blackhole_ops);
3901         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3902 }