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, int ifindex,
 106                                            unsigned int pref);
 107 static struct rt6_info *rt6_get_route_info(struct net *net,
 108                                            const struct in6_addr *prefix, int prefixlen,
 109                                            const struct in6_addr *gwaddr, int ifindex);
 110 #endif
 111
 112 struct uncached_list {
 113         spinlock_t              lock;
 114         struct list_head        head;
 115 };
 116
 117 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 118
 119 static void rt6_uncached_list_add(struct rt6_info *rt)
 120 {
 121         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 122
 123         rt->dst.flags |= DST_NOCACHE;
 124         rt->rt6i_uncached_list = ul;
 125
 126         spin_lock_bh(&ul->lock);
 127         list_add_tail(&rt->rt6i_uncached, &ul->head);
 128         spin_unlock_bh(&ul->lock);
 129 }
 130
 131 static void rt6_uncached_list_del(struct rt6_info *rt)
 132 {
 133         if (!list_empty(&rt->rt6i_uncached)) {
 134                 struct uncached_list *ul = rt->rt6i_uncached_list;
 135
 136                 spin_lock_bh(&ul->lock);
 137                 list_del(&rt->rt6i_uncached);
 138                 spin_unlock_bh(&ul->lock);
 139         }
 140 }
 141
 142 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 143 {
 144         struct net_device *loopback_dev = net->loopback_dev;
 145         int cpu;
 146
 147         if (dev == loopback_dev)
 148                 return;
 149
 150         for_each_possible_cpu(cpu) {
 151                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 152                 struct rt6_info *rt;
 153
 154                 spin_lock_bh(&ul->lock);
 155                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 156                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 157                         struct net_device *rt_dev = rt->dst.dev;
 158
 159                         if (rt_idev->dev == dev) {
 160                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 161                                 in6_dev_put(rt_idev);
 162                         }
 163
 164                         if (rt_dev == dev) {
 165                                 rt->dst.dev = loopback_dev;
 166                                 dev_hold(rt->dst.dev);
 167                                 dev_put(rt_dev);
 168                         }
 169                 }
 170                 spin_unlock_bh(&ul->lock);
 171         }
 172 }
 173
 174 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 175 {
 176         return dst_metrics_write_ptr(rt->dst.from);
 177 }
 178
 179 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 180 {
 181         struct rt6_info *rt = (struct rt6_info *)dst;
 182
 183         if (rt->rt6i_flags & RTF_PCPU)
 184                 return rt6_pcpu_cow_metrics(rt);
 185         else if (rt->rt6i_flags & RTF_CACHE)
 186                 return NULL;
 187         else
 188                 return dst_cow_metrics_generic(dst, old);
 189 }
 190
 191 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 192                                              struct sk_buff *skb,
 193                                              const void *daddr)
 194 {
 195         struct in6_addr *p = &rt->rt6i_gateway;
 196
 197         if (!ipv6_addr_any(p))
 198                 return (const void *) p;
 199         else if (skb)
 200                 return &ipv6_hdr(skb)->daddr;
 201         return daddr;
 202 }
 203
 204 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 205                                           struct sk_buff *skb,
 206                                           const void *daddr)
 207 {
 208         struct rt6_info *rt = (struct rt6_info *) dst;
 209         struct neighbour *n;
 210
 211         daddr = choose_neigh_daddr(rt, skb, daddr);
 212         n = __ipv6_neigh_lookup(dst->dev, daddr);
 213         if (n)
 214                 return n;
 215         return neigh_create(&nd_tbl, daddr, dst->dev);
 216 }
 217
 218 static struct dst_ops ip6_dst_ops_template = {
 219         .family                 =       AF_INET6,
 220         .gc                     =       ip6_dst_gc,
 221         .gc_thresh              =       1024,
 222         .check                  =       ip6_dst_check,
 223         .default_advmss         =       ip6_default_advmss,
 224         .mtu                    =       ip6_mtu,
 225         .cow_metrics            =       ipv6_cow_metrics,
 226         .destroy                =       ip6_dst_destroy,
 227         .ifdown                 =       ip6_dst_ifdown,
 228         .negative_advice        =       ip6_negative_advice,
 229         .link_failure           =       ip6_link_failure,
 230         .update_pmtu            =       ip6_rt_update_pmtu,
 231         .redirect               =       rt6_do_redirect,
 232         .local_out              =       __ip6_local_out,
 233         .neigh_lookup           =       ip6_neigh_lookup,
 234 };
 235
 236 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 237 {
 238         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 239
 240         return mtu ? : dst->dev->mtu;
 241 }
 242
 243 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 244                                          struct sk_buff *skb, u32 mtu)
 245 {
 246 }
 247
 248 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 249                                       struct sk_buff *skb)
 250 {
 251 }
 252
 253 static struct dst_ops ip6_dst_blackhole_ops = {
 254         .family                 =       AF_INET6,
 255         .destroy                =       ip6_dst_destroy,
 256         .check                  =       ip6_dst_check,
 257         .mtu                    =       ip6_blackhole_mtu,
 258         .default_advmss         =       ip6_default_advmss,
 259         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 260         .redirect               =       ip6_rt_blackhole_redirect,
 261         .cow_metrics            =       dst_cow_metrics_generic,
 262         .neigh_lookup           =       ip6_neigh_lookup,
 263 };
 264
 265 static const u32 ip6_template_metrics[RTAX_MAX] = {
 266         [RTAX_HOPLIMIT - 1] = 0,
 267 };
 268
 269 static const struct rt6_info ip6_null_entry_template = {
 270         .dst = {
 271                 .__refcnt       = ATOMIC_INIT(1),
 272                 .__use          = 1,
 273                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 274                 .error          = -ENETUNREACH,
 275                 .input          = ip6_pkt_discard,
 276                 .output         = ip6_pkt_discard_out,
 277         },
 278         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 279         .rt6i_protocol  = RTPROT_KERNEL,
 280         .rt6i_metric    = ~(u32) 0,
 281         .rt6i_ref       = ATOMIC_INIT(1),
 282 };
 283
 284 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 285
 286 static const struct rt6_info ip6_prohibit_entry_template = {
 287         .dst = {
 288                 .__refcnt       = ATOMIC_INIT(1),
 289                 .__use          = 1,
 290                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 291                 .error          = -EACCES,
 292                 .input          = ip6_pkt_prohibit,
 293                 .output         = ip6_pkt_prohibit_out,
 294         },
 295         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 296         .rt6i_protocol  = RTPROT_KERNEL,
 297         .rt6i_metric    = ~(u32) 0,
 298         .rt6i_ref       = ATOMIC_INIT(1),
 299 };
 300
 301 static const struct rt6_info ip6_blk_hole_entry_template = {
 302         .dst = {
 303                 .__refcnt       = ATOMIC_INIT(1),
 304                 .__use          = 1,
 305                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 306                 .error          = -EINVAL,
 307                 .input          = dst_discard,
 308                 .output         = dst_discard_out,
 309         },
 310         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 311         .rt6i_protocol  = RTPROT_KERNEL,
 312         .rt6i_metric    = ~(u32) 0,
 313         .rt6i_ref       = ATOMIC_INIT(1),
 314 };
 315
 316 #endif
 317
 318 static void rt6_info_init(struct rt6_info *rt)
 319 {
 320         struct dst_entry *dst = &rt->dst;
 321
 322         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 323         INIT_LIST_HEAD(&rt->rt6i_siblings);
 324         INIT_LIST_HEAD(&rt->rt6i_uncached);
 325 }
 326
 327 /* allocate dst with ip6_dst_ops */
 328 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 329                                         struct net_device *dev,
 330                                         int flags)
 331 {
 332         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 333                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 334
 335         if (rt)
 336                 rt6_info_init(rt);
 337
 338         return rt;
 339 }
 340
 341 struct rt6_info *ip6_dst_alloc(struct net *net,
 342                                struct net_device *dev,
 343                                int flags)
 344 {
 345         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 346
 347         if (rt) {
 348                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 349                 if (rt->rt6i_pcpu) {
 350                         int cpu;
 351
 352                         for_each_possible_cpu(cpu) {
 353                                 struct rt6_info **p;
 354
 355                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 356                                 /* no one shares rt */
 357                                 *p =  NULL;
 358                         }
 359                 } else {
 360                         dst_destroy((struct dst_entry *)rt);
 361                         return NULL;
 362                 }
 363         }
 364
 365         return rt;
 366 }
 367 EXPORT_SYMBOL(ip6_dst_alloc);
 368
 369 static void ip6_dst_destroy(struct dst_entry *dst)
 370 {
 371         struct rt6_info *rt = (struct rt6_info *)dst;
 372         struct dst_entry *from = dst->from;
 373         struct inet6_dev *idev;
 374
 375         dst_destroy_metrics_generic(dst);
 376         free_percpu(rt->rt6i_pcpu);
 377         rt6_uncached_list_del(rt);
 378
 379         idev = rt->rt6i_idev;
 380         if (idev) {
 381                 rt->rt6i_idev = NULL;
 382                 in6_dev_put(idev);
 383         }
 384
 385         dst->from = NULL;
 386         dst_release(from);
 387 }
 388
 389 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 390                            int how)
 391 {
 392         struct rt6_info *rt = (struct rt6_info *)dst;
 393         struct inet6_dev *idev = rt->rt6i_idev;
 394         struct net_device *loopback_dev =
 395                 dev_net(dev)->loopback_dev;
 396
 397         if (dev != loopback_dev) {
 398                 if (idev && idev->dev == dev) {
 399                         struct inet6_dev *loopback_idev =
 400                                 in6_dev_get(loopback_dev);
 401                         if (loopback_idev) {
 402                                 rt->rt6i_idev = loopback_idev;
 403                                 in6_dev_put(idev);
 404                         }
 405                 }
 406         }
 407 }
 408
 409 static bool __rt6_check_expired(const struct rt6_info *rt)
 410 {
 411         if (rt->rt6i_flags & RTF_EXPIRES)
 412                 return time_after(jiffies, rt->dst.expires);
 413         else
 414                 return false;
 415 }
 416
 417 static bool rt6_check_expired(const struct rt6_info *rt)
 418 {
 419         if (rt->rt6i_flags & RTF_EXPIRES) {
 420                 if (time_after(jiffies, rt->dst.expires))
 421                         return true;
 422         } else if (rt->dst.from) {
 423                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 424         }
 425         return false;
 426 }
 427
 428 /* Multipath route selection:
 429  *   Hash based function using packet header and flowlabel.
 430  * Adapted from fib_info_hashfn()
 431  */
 432 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 433                                const struct flowi6 *fl6)
 434 {
 435         return get_hash_from_flowi6(fl6) % candidate_count;
 436 }
 437
 438 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 439                                              struct flowi6 *fl6, int oif,
 440                                              int strict)
 441 {
 442         struct rt6_info *sibling, *next_sibling;
 443         int route_choosen;
 444
 445         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 446         /* Don't change the route, if route_choosen == 0
 447          * (siblings does not include ourself)
 448          */
 449         if (route_choosen)
 450                 list_for_each_entry_safe(sibling, next_sibling,
 451                                 &match->rt6i_siblings, rt6i_siblings) {
 452                         route_choosen--;
 453                         if (route_choosen == 0) {
 454                                 if (rt6_score_route(sibling, oif, strict) < 0)
 455                                         break;
 456                                 match = sibling;
 457                                 break;
 458                         }
 459                 }
 460         return match;
 461 }
 462
 463 /*
 464  *      Route lookup. Any table->tb6_lock is implied.
 465  */
 466
 467 static inline struct rt6_info *rt6_device_match(struct net *net,
 468                                                     struct rt6_info *rt,
 469                                                     const struct in6_addr *saddr,
 470                                                     int oif,
 471                                                     int flags)
 472 {
 473         struct rt6_info *local = NULL;
 474         struct rt6_info *sprt;
 475
 476         if (!oif && ipv6_addr_any(saddr))
 477                 goto out;
 478
 479         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 480                 struct net_device *dev = sprt->dst.dev;
 481
 482                 if (oif) {
 483                         if (dev->ifindex == oif)
 484                                 return sprt;
 485                         if (dev->flags & IFF_LOOPBACK) {
 486                                 if (!sprt->rt6i_idev ||
 487                                     sprt->rt6i_idev->dev->ifindex != oif) {
 488                                         if (flags & RT6_LOOKUP_F_IFACE)
 489                                                 continue;
 490                                         if (local &&
 491                                             local->rt6i_idev->dev->ifindex == oif)
 492                                                 continue;
 493                                 }
 494                                 local = sprt;
 495                         }
 496                 } else {
 497                         if (ipv6_chk_addr(net, saddr, dev,
 498                                           flags & RT6_LOOKUP_F_IFACE))
 499                                 return sprt;
 500                 }
 501         }
 502
 503         if (oif) {
 504                 if (local)
 505                         return local;
 506
 507                 if (flags & RT6_LOOKUP_F_IFACE)
 508                         return net->ipv6.ip6_null_entry;
 509         }
 510 out:
 511         return rt;
 512 }
 513
 514 #ifdef CONFIG_IPV6_ROUTER_PREF
 515 struct __rt6_probe_work {
 516         struct work_struct work;
 517         struct in6_addr target;
 518         struct net_device *dev;
 519 };
 520
 521 static void rt6_probe_deferred(struct work_struct *w)
 522 {
 523         struct in6_addr mcaddr;
 524         struct __rt6_probe_work *work =
 525                 container_of(w, struct __rt6_probe_work, work);
 526
 527         addrconf_addr_solict_mult(&work->target, &mcaddr);
 528         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL);
 529         dev_put(work->dev);
 530         kfree(work);
 531 }
 532
 533 static void rt6_probe(struct rt6_info *rt)
 534 {
 535         struct __rt6_probe_work *work;
 536         struct neighbour *neigh;
 537         /*
 538          * Okay, this does not seem to be appropriate
 539          * for now, however, we need to check if it
 540          * is really so; aka Router Reachability Probing.
 541          *
 542          * Router Reachability Probe MUST be rate-limited
 543          * to no more than one per minute.
 544          */
 545         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 546                 return;
 547         rcu_read_lock_bh();
 548         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 549         if (neigh) {
 550                 if (neigh->nud_state & NUD_VALID)
 551                         goto out;
 552
 553                 work = NULL;
 554                 write_lock(&neigh->lock);
 555                 if (!(neigh->nud_state & NUD_VALID) &&
 556                     time_after(jiffies,
 557                                neigh->updated +
 558                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 559                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 560                         if (work)
 561                                 __neigh_set_probe_once(neigh);
 562                 }
 563                 write_unlock(&neigh->lock);
 564         } else {
 565                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 566         }
 567
 568         if (work) {
 569                 INIT_WORK(&work->work, rt6_probe_deferred);
 570                 work->target = rt->rt6i_gateway;
 571                 dev_hold(rt->dst.dev);
 572                 work->dev = rt->dst.dev;
 573                 schedule_work(&work->work);
 574         }
 575
 576 out:
 577         rcu_read_unlock_bh();
 578 }
 579 #else
 580 static inline void rt6_probe(struct rt6_info *rt)
 581 {
 582 }
 583 #endif
 584
 585 /*
 586  * Default Router Selection (RFC 2461 6.3.6)
 587  */
 588 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 589 {
 590         struct net_device *dev = rt->dst.dev;
 591         if (!oif || dev->ifindex == oif)
 592                 return 2;
 593         if ((dev->flags & IFF_LOOPBACK) &&
 594             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 595                 return 1;
 596         return 0;
 597 }
 598
 599 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 600 {
 601         struct neighbour *neigh;
 602         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 603
 604         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 605             !(rt->rt6i_flags & RTF_GATEWAY))
 606                 return RT6_NUD_SUCCEED;
 607
 608         rcu_read_lock_bh();
 609         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 610         if (neigh) {
 611                 read_lock(&neigh->lock);
 612                 if (neigh->nud_state & NUD_VALID)
 613                         ret = RT6_NUD_SUCCEED;
 614 #ifdef CONFIG_IPV6_ROUTER_PREF
 615                 else if (!(neigh->nud_state & NUD_FAILED))
 616                         ret = RT6_NUD_SUCCEED;
 617                 else
 618                         ret = RT6_NUD_FAIL_PROBE;
 619 #endif
 620                 read_unlock(&neigh->lock);
 621         } else {
 622                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 623                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 624         }
 625         rcu_read_unlock_bh();
 626
 627         return ret;
 628 }
 629
 630 static int rt6_score_route(struct rt6_info *rt, int oif,
 631                            int strict)
 632 {
 633         int m;
 634
 635         m = rt6_check_dev(rt, oif);
 636         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 637                 return RT6_NUD_FAIL_HARD;
 638 #ifdef CONFIG_IPV6_ROUTER_PREF
 639         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 640 #endif
 641         if (strict & RT6_LOOKUP_F_REACHABLE) {
 642                 int n = rt6_check_neigh(rt);
 643                 if (n < 0)
 644                         return n;
 645         }
 646         return m;
 647 }
 648
 649 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 650                                    int *mpri, struct rt6_info *match,
 651                                    bool *do_rr)
 652 {
 653         int m;
 654         bool match_do_rr = false;
 655         struct inet6_dev *idev = rt->rt6i_idev;
 656         struct net_device *dev = rt->dst.dev;
 657
 658         if (dev && !netif_carrier_ok(dev) &&
 659             idev->cnf.ignore_routes_with_linkdown)
 660                 goto out;
 661
 662         if (rt6_check_expired(rt))
 663                 goto out;
 664
 665         m = rt6_score_route(rt, oif, strict);
 666         if (m == RT6_NUD_FAIL_DO_RR) {
 667                 match_do_rr = true;
 668                 m = 0; /* lowest valid score */
 669         } else if (m == RT6_NUD_FAIL_HARD) {
 670                 goto out;
 671         }
 672
 673         if (strict & RT6_LOOKUP_F_REACHABLE)
 674                 rt6_probe(rt);
 675
 676         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 677         if (m > *mpri) {
 678                 *do_rr = match_do_rr;
 679                 *mpri = m;
 680                 match = rt;
 681         }
 682 out:
 683         return match;
 684 }
 685
 686 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 687                                      struct rt6_info *rr_head,
 688                                      u32 metric, int oif, int strict,
 689                                      bool *do_rr)
 690 {
 691         struct rt6_info *rt, *match, *cont;
 692         int mpri = -1;
 693
 694         match = NULL;
 695         cont = NULL;
 696         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 697                 if (rt->rt6i_metric != metric) {
 698                         cont = rt;
 699                         break;
 700                 }
 701
 702                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 703         }
 704
 705         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 706                 if (rt->rt6i_metric != metric) {
 707                         cont = rt;
 708                         break;
 709                 }
 710
 711                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 712         }
 713
 714         if (match || !cont)
 715                 return match;
 716
 717         for (rt = cont; rt; rt = rt->dst.rt6_next)
 718                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 719
 720         return match;
 721 }
 722
 723 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 724 {
 725         struct rt6_info *match, *rt0;
 726         struct net *net;
 727         bool do_rr = false;
 728
 729         rt0 = fn->rr_ptr;
 730         if (!rt0)
 731                 fn->rr_ptr = rt0 = fn->leaf;
 732
 733         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 734                              &do_rr);
 735
 736         if (do_rr) {
 737                 struct rt6_info *next = rt0->dst.rt6_next;
 738
 739                 /* no entries matched; do round-robin */
 740                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 741                         next = fn->leaf;
 742
 743                 if (next != rt0)
 744                         fn->rr_ptr = next;
 745         }
 746
 747         net = dev_net(rt0->dst.dev);
 748         return match ? match : net->ipv6.ip6_null_entry;
 749 }
 750
 751 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 752 {
 753         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 754 }
 755
 756 #ifdef CONFIG_IPV6_ROUTE_INFO
 757 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 758                   const struct in6_addr *gwaddr)
 759 {
 760         struct net *net = dev_net(dev);
 761         struct route_info *rinfo = (struct route_info *) opt;
 762         struct in6_addr prefix_buf, *prefix;
 763         unsigned int pref;
 764         unsigned long lifetime;
 765         struct rt6_info *rt;
 766
 767         if (len < sizeof(struct route_info)) {
 768                 return -EINVAL;
 769         }
 770
 771         /* Sanity check for prefix_len and length */
 772         if (rinfo->length > 3) {
 773                 return -EINVAL;
 774         } else if (rinfo->prefix_len > 128) {
 775                 return -EINVAL;
 776         } else if (rinfo->prefix_len > 64) {
 777                 if (rinfo->length < 2) {
 778                         return -EINVAL;
 779                 }
 780         } else if (rinfo->prefix_len > 0) {
 781                 if (rinfo->length < 1) {
 782                         return -EINVAL;
 783                 }
 784         }
 785
 786         pref = rinfo->route_pref;
 787         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 788                 return -EINVAL;
 789
 790         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 791
 792         if (rinfo->length == 3)
 793                 prefix = (struct in6_addr *)rinfo->prefix;
 794         else {
 795                 /* this function is safe */
 796                 ipv6_addr_prefix(&prefix_buf,
 797                                  (struct in6_addr *)rinfo->prefix,
 798                                  rinfo->prefix_len);
 799                 prefix = &prefix_buf;
 800         }
 801
 802         if (rinfo->prefix_len == 0)
 803                 rt = rt6_get_dflt_router(gwaddr, dev);
 804         else
 805                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 806                                         gwaddr, dev->ifindex);
 807
 808         if (rt && !lifetime) {
 809                 ip6_del_rt(rt);
 810                 rt = NULL;
 811         }
 812
 813         if (!rt && lifetime)
 814                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 815                                         pref);
 816         else if (rt)
 817                 rt->rt6i_flags = RTF_ROUTEINFO |
 818                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 819
 820         if (rt) {
 821                 if (!addrconf_finite_timeout(lifetime))
 822                         rt6_clean_expires(rt);
 823                 else
 824                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 825
 826                 ip6_rt_put(rt);
 827         }
 828         return 0;
 829 }
 830 #endif
 831
 832 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 833                                         struct in6_addr *saddr)
 834 {
 835         struct fib6_node *pn;
 836         while (1) {
 837                 if (fn->fn_flags & RTN_TL_ROOT)
 838                         return NULL;
 839                 pn = fn->parent;
 840                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 841                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 842                 else
 843                         fn = pn;
 844                 if (fn->fn_flags & RTN_RTINFO)
 845                         return fn;
 846         }
 847 }
 848
 849 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 850                                              struct fib6_table *table,
 851                                              struct flowi6 *fl6, int flags)
 852 {
 853         struct fib6_node *fn;
 854         struct rt6_info *rt;
 855
 856         read_lock_bh(&table->tb6_lock);
 857         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 858 restart:
 859         rt = fn->leaf;
 860         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 861         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 862                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 863         if (rt == net->ipv6.ip6_null_entry) {
 864                 fn = fib6_backtrack(fn, &fl6->saddr);
 865                 if (fn)
 866                         goto restart;
 867         }
 868         dst_use(&rt->dst, jiffies);
 869         read_unlock_bh(&table->tb6_lock);
 870
 871         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
 872
 873         return rt;
 874
 875 }
 876
 877 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 878                                     int flags)
 879 {
 880         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 881 }
 882 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 883
 884 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 885                             const struct in6_addr *saddr, int oif, int strict)
 886 {
 887         struct flowi6 fl6 = {
 888                 .flowi6_oif = oif,
 889                 .daddr = *daddr,
 890         };
 891         struct dst_entry *dst;
 892         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 893
 894         if (saddr) {
 895                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 896                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 897         }
 898
 899         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 900         if (dst->error == 0)
 901                 return (struct rt6_info *) dst;
 902
 903         dst_release(dst);
 904
 905         return NULL;
 906 }
 907 EXPORT_SYMBOL(rt6_lookup);
 908
 909 /* ip6_ins_rt is called with FREE table->tb6_lock.
 910    It takes new route entry, the addition fails by any reason the
 911    route is freed. In any case, if caller does not hold it, it may
 912    be destroyed.
 913  */
 914
 915 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 916                         struct mx6_config *mxc)
 917 {
 918         int err;
 919         struct fib6_table *table;
 920
 921         table = rt->rt6i_table;
 922         write_lock_bh(&table->tb6_lock);
 923         err = fib6_add(&table->tb6_root, rt, info, mxc);
 924         write_unlock_bh(&table->tb6_lock);
 925
 926         return err;
 927 }
 928
 929 int ip6_ins_rt(struct rt6_info *rt)
 930 {
 931         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 932         struct mx6_config mxc = { .mx = NULL, };
 933
 934         return __ip6_ins_rt(rt, &info, &mxc);
 935 }
 936
 937 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 938                                            const struct in6_addr *daddr,
 939                                            const struct in6_addr *saddr)
 940 {
 941         struct rt6_info *rt;
 942
 943         /*
 944          *      Clone the route.
 945          */
 946
 947         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 948                 ort = (struct rt6_info *)ort->dst.from;
 949
 950         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 951
 952         if (!rt)
 953                 return NULL;
 954
 955         ip6_rt_copy_init(rt, ort);
 956         rt->rt6i_flags |= RTF_CACHE;
 957         rt->rt6i_metric = 0;
 958         rt->dst.flags |= DST_HOST;
 959         rt->rt6i_dst.addr = *daddr;
 960         rt->rt6i_dst.plen = 128;
 961
 962         if (!rt6_is_gw_or_nonexthop(ort)) {
 963                 if (ort->rt6i_dst.plen != 128 &&
 964                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 965                         rt->rt6i_flags |= RTF_ANYCAST;
 966 #ifdef CONFIG_IPV6_SUBTREES
 967                 if (rt->rt6i_src.plen && saddr) {
 968                         rt->rt6i_src.addr = *saddr;
 969                         rt->rt6i_src.plen = 128;
 970                 }
 971 #endif
 972         }
 973
 974         return rt;
 975 }
 976
 977 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 978 {
 979         struct rt6_info *pcpu_rt;
 980
 981         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 982                                   rt->dst.dev, rt->dst.flags);
 983
 984         if (!pcpu_rt)
 985                 return NULL;
 986         ip6_rt_copy_init(pcpu_rt, rt);
 987         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 988         pcpu_rt->rt6i_flags |= RTF_PCPU;
 989         return pcpu_rt;
 990 }
 991
 992 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 993 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 994 {
 995         struct rt6_info *pcpu_rt, **p;
 996
 997         p = this_cpu_ptr(rt->rt6i_pcpu);
 998         pcpu_rt = *p;
 999
1000         if (pcpu_rt) {
1001                 dst_hold(&pcpu_rt->dst);
1002                 rt6_dst_from_metrics_check(pcpu_rt);
1003         }
1004         return pcpu_rt;
1005 }
1006
1007 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1008 {
1009         struct fib6_table *table = rt->rt6i_table;
1010         struct rt6_info *pcpu_rt, *prev, **p;
1011
1012         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1013         if (!pcpu_rt) {
1014                 struct net *net = dev_net(rt->dst.dev);
1015
1016                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1017                 return net->ipv6.ip6_null_entry;
1018         }
1019
1020         read_lock_bh(&table->tb6_lock);
1021         if (rt->rt6i_pcpu) {
1022                 p = this_cpu_ptr(rt->rt6i_pcpu);
1023                 prev = cmpxchg(p, NULL, pcpu_rt);
1024                 if (prev) {
1025                         /* If someone did it before us, return prev instead */
1026                         dst_destroy(&pcpu_rt->dst);
1027                         pcpu_rt = prev;
1028                 }
1029         } else {
1030                 /* rt has been removed from the fib6 tree
1031                  * before we have a chance to acquire the read_lock.
1032                  * In this case, don't brother to create a pcpu rt
1033                  * since rt is going away anyway.  The next
1034                  * dst_check() will trigger a re-lookup.
1035                  */
1036                 dst_destroy(&pcpu_rt->dst);
1037                 pcpu_rt = rt;
1038         }
1039         dst_hold(&pcpu_rt->dst);
1040         rt6_dst_from_metrics_check(pcpu_rt);
1041         read_unlock_bh(&table->tb6_lock);
1042         return pcpu_rt;
1043 }
1044
1045 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
1046                                int oif, struct flowi6 *fl6, int flags)
1047 {
1048         struct fib6_node *fn, *saved_fn;
1049         struct rt6_info *rt;
1050         int strict = 0;
1051
1052         strict |= flags & RT6_LOOKUP_F_IFACE;
1053         if (net->ipv6.devconf_all->forwarding == 0)
1054                 strict |= RT6_LOOKUP_F_REACHABLE;
1055
1056         read_lock_bh(&table->tb6_lock);
1057
1058         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1059         saved_fn = fn;
1060
1061         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1062                 oif = 0;
1063
1064 redo_rt6_select:
1065         rt = rt6_select(fn, oif, strict);
1066         if (rt->rt6i_nsiblings)
1067                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1068         if (rt == net->ipv6.ip6_null_entry) {
1069                 fn = fib6_backtrack(fn, &fl6->saddr);
1070                 if (fn)
1071                         goto redo_rt6_select;
1072                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1073                         /* also consider unreachable route */
1074                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1075                         fn = saved_fn;
1076                         goto redo_rt6_select;
1077                 }
1078         }
1079
1080
1081         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1082                 dst_use(&rt->dst, jiffies);
1083                 read_unlock_bh(&table->tb6_lock);
1084
1085                 rt6_dst_from_metrics_check(rt);
1086
1087                 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1088                 return rt;
1089         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1090                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1091                 /* Create a RTF_CACHE clone which will not be
1092                  * owned by the fib6 tree.  It is for the special case where
1093                  * the daddr in the skb during the neighbor look-up is different
1094                  * from the fl6->daddr used to look-up route here.
1095                  */
1096
1097                 struct rt6_info *uncached_rt;
1098
1099                 dst_use(&rt->dst, jiffies);
1100                 read_unlock_bh(&table->tb6_lock);
1101
1102                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1103                 dst_release(&rt->dst);
1104
1105                 if (uncached_rt)
1106                         rt6_uncached_list_add(uncached_rt);
1107                 else
1108                         uncached_rt = net->ipv6.ip6_null_entry;
1109
1110                 dst_hold(&uncached_rt->dst);
1111
1112                 trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
1113                 return uncached_rt;
1114
1115         } else {
1116                 /* Get a percpu copy */
1117
1118                 struct rt6_info *pcpu_rt;
1119
1120                 rt->dst.lastuse = jiffies;
1121                 rt->dst.__use++;
1122                 pcpu_rt = rt6_get_pcpu_route(rt);
1123
1124                 if (pcpu_rt) {
1125                         read_unlock_bh(&table->tb6_lock);
1126                 } else {
1127                         /* We have to do the read_unlock first
1128                          * because rt6_make_pcpu_route() may trigger
1129                          * ip6_dst_gc() which will take the write_lock.
1130                          */
1131                         dst_hold(&rt->dst);
1132                         read_unlock_bh(&table->tb6_lock);
1133                         pcpu_rt = rt6_make_pcpu_route(rt);
1134                         dst_release(&rt->dst);
1135                 }
1136
1137                 trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
1138                 return pcpu_rt;
1139
1140         }
1141 }
1142 EXPORT_SYMBOL_GPL(ip6_pol_route);
1143
1144 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1145                                             struct flowi6 *fl6, int flags)
1146 {
1147         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1148 }
1149
1150 struct dst_entry *ip6_route_input_lookup(struct net *net,
1151                                          struct net_device *dev,
1152                                          struct flowi6 *fl6, int flags)
1153 {
1154         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1155                 flags |= RT6_LOOKUP_F_IFACE;
1156
1157         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1158 }
1159 EXPORT_SYMBOL_GPL(ip6_route_input_lookup);
1160
1161 void ip6_route_input(struct sk_buff *skb)
1162 {
1163         const struct ipv6hdr *iph = ipv6_hdr(skb);
1164         struct net *net = dev_net(skb->dev);
1165         int flags = RT6_LOOKUP_F_HAS_SADDR;
1166         struct ip_tunnel_info *tun_info;
1167         struct flowi6 fl6 = {
1168                 .flowi6_iif = skb->dev->ifindex,
1169                 .daddr = iph->daddr,
1170                 .saddr = iph->saddr,
1171                 .flowlabel = ip6_flowinfo(iph),
1172                 .flowi6_mark = skb->mark,
1173                 .flowi6_proto = iph->nexthdr,
1174         };
1175
1176         tun_info = skb_tunnel_info(skb);
1177         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1178                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1179         skb_dst_drop(skb);
1180         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1181 }
1182
1183 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1184                                              struct flowi6 *fl6, int flags)
1185 {
1186         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1187 }
1188
1189 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1190                                          struct flowi6 *fl6, int flags)
1191 {
1192         bool any_src;
1193
1194         if (rt6_need_strict(&fl6->daddr)) {
1195                 struct dst_entry *dst;
1196
1197                 dst = l3mdev_link_scope_lookup(net, fl6);
1198                 if (dst)
1199                         return dst;
1200         }
1201
1202         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1203
1204         any_src = ipv6_addr_any(&fl6->saddr);
1205         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1206             (fl6->flowi6_oif && any_src))
1207                 flags |= RT6_LOOKUP_F_IFACE;
1208
1209         if (!any_src)
1210                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1211         else if (sk)
1212                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1213
1214         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1215 }
1216 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1217
1218 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1219 {
1220         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1221         struct dst_entry *new = NULL;
1222
1223         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1224         if (rt) {
1225                 rt6_info_init(rt);
1226
1227                 new = &rt->dst;
1228                 new->__use = 1;
1229                 new->input = dst_discard;
1230                 new->output = dst_discard_out;
1231
1232                 dst_copy_metrics(new, &ort->dst);
1233                 rt->rt6i_idev = ort->rt6i_idev;
1234                 if (rt->rt6i_idev)
1235                         in6_dev_hold(rt->rt6i_idev);
1236
1237                 rt->rt6i_gateway = ort->rt6i_gateway;
1238                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1239                 rt->rt6i_metric = 0;
1240
1241                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1242 #ifdef CONFIG_IPV6_SUBTREES
1243                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1244 #endif
1245
1246                 dst_free(new);
1247         }
1248
1249         dst_release(dst_orig);
1250         return new ? new : ERR_PTR(-ENOMEM);
1251 }
1252
1253 /*
1254  *      Destination cache support functions
1255  */
1256
1257 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1258 {
1259         if (rt->dst.from &&
1260             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1261                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1262 }
1263
1264 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1265 {
1266         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1267                 return NULL;
1268
1269         if (rt6_check_expired(rt))
1270                 return NULL;
1271
1272         return &rt->dst;
1273 }
1274
1275 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1276 {
1277         if (!__rt6_check_expired(rt) &&
1278             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1279             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1280                 return &rt->dst;
1281         else
1282                 return NULL;
1283 }
1284
1285 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1286 {
1287         struct rt6_info *rt;
1288
1289         rt = (struct rt6_info *) dst;
1290
1291         /* All IPV6 dsts are created with ->obsolete set to the value
1292          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1293          * into this function always.
1294          */
1295
1296         rt6_dst_from_metrics_check(rt);
1297
1298         if (rt->rt6i_flags & RTF_PCPU ||
1299             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1300                 return rt6_dst_from_check(rt, cookie);
1301         else
1302                 return rt6_check(rt, cookie);
1303 }
1304
1305 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1306 {
1307         struct rt6_info *rt = (struct rt6_info *) dst;
1308
1309         if (rt) {
1310                 if (rt->rt6i_flags & RTF_CACHE) {
1311                         if (rt6_check_expired(rt)) {
1312                                 ip6_del_rt(rt);
1313                                 dst = NULL;
1314                         }
1315                 } else {
1316                         dst_release(dst);
1317                         dst = NULL;
1318                 }
1319         }
1320         return dst;
1321 }
1322
1323 static void ip6_link_failure(struct sk_buff *skb)
1324 {
1325         struct rt6_info *rt;
1326
1327         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1328
1329         rt = (struct rt6_info *) skb_dst(skb);
1330         if (rt) {
1331                 if (rt->rt6i_flags & RTF_CACHE) {
1332                         dst_hold(&rt->dst);
1333                         ip6_del_rt(rt);
1334                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1335                         rt->rt6i_node->fn_sernum = -1;
1336                 }
1337         }
1338 }
1339
1340 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1341 {
1342         struct net *net = dev_net(rt->dst.dev);
1343
1344         rt->rt6i_flags |= RTF_MODIFIED;
1345         rt->rt6i_pmtu = mtu;
1346         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1347 }
1348
1349 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1350 {
1351         return !(rt->rt6i_flags & RTF_CACHE) &&
1352                 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1353 }
1354
1355 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1356                                  const struct ipv6hdr *iph, u32 mtu)
1357 {
1358         struct rt6_info *rt6 = (struct rt6_info *)dst;
1359
1360         if (rt6->rt6i_flags & RTF_LOCAL)
1361                 return;
1362
1363         dst_confirm(dst);
1364         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1365         if (mtu >= dst_mtu(dst))
1366                 return;
1367
1368         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1369                 rt6_do_update_pmtu(rt6, mtu);
1370         } else {
1371                 const struct in6_addr *daddr, *saddr;
1372                 struct rt6_info *nrt6;
1373
1374                 if (iph) {
1375                         daddr = &iph->daddr;
1376                         saddr = &iph->saddr;
1377                 } else if (sk) {
1378                         daddr = &sk->sk_v6_daddr;
1379                         saddr = &inet6_sk(sk)->saddr;
1380                 } else {
1381                         return;
1382                 }
1383                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1384                 if (nrt6) {
1385                         rt6_do_update_pmtu(nrt6, mtu);
1386
1387                         /* ip6_ins_rt(nrt6) will bump the
1388                          * rt6->rt6i_node->fn_sernum
1389                          * which will fail the next rt6_check() and
1390                          * invalidate the sk->sk_dst_cache.
1391                          */
1392                         ip6_ins_rt(nrt6);
1393                 }
1394         }
1395 }
1396
1397 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1398                                struct sk_buff *skb, u32 mtu)
1399 {
1400         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1401 }
1402
1403 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1404                      int oif, u32 mark)
1405 {
1406         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1407         struct dst_entry *dst;
1408         struct flowi6 fl6;
1409
1410         memset(&fl6, 0, sizeof(fl6));
1411         fl6.flowi6_oif = oif;
1412         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1413         fl6.daddr = iph->daddr;
1414         fl6.saddr = iph->saddr;
1415         fl6.flowlabel = ip6_flowinfo(iph);
1416
1417         dst = ip6_route_output(net, NULL, &fl6);
1418         if (!dst->error)
1419                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1420         dst_release(dst);
1421 }
1422 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1423
1424 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1425 {
1426         struct dst_entry *dst;
1427
1428         ip6_update_pmtu(skb, sock_net(sk), mtu,
1429                         sk->sk_bound_dev_if, sk->sk_mark);
1430
1431         dst = __sk_dst_get(sk);
1432         if (!dst || !dst->obsolete ||
1433             dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
1434                 return;
1435
1436         bh_lock_sock(sk);
1437         if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1438                 ip6_datagram_dst_update(sk, false);
1439         bh_unlock_sock(sk);
1440 }
1441 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1442
1443 /* Handle redirects */
1444 struct ip6rd_flowi {
1445         struct flowi6 fl6;
1446         struct in6_addr gateway;
1447 };
1448
1449 static struct rt6_info *__ip6_route_redirect(struct net *net,
1450                                              struct fib6_table *table,
1451                                              struct flowi6 *fl6,
1452                                              int flags)
1453 {
1454         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1455         struct rt6_info *rt;
1456         struct fib6_node *fn;
1457
1458         /* Get the "current" route for this destination and
1459          * check if the redirect has come from approriate router.
1460          *
1461          * RFC 4861 specifies that redirects should only be
1462          * accepted if they come from the nexthop to the target.
1463          * Due to the way the routes are chosen, this notion
1464          * is a bit fuzzy and one might need to check all possible
1465          * routes.
1466          */
1467
1468         read_lock_bh(&table->tb6_lock);
1469         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1470 restart:
1471         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1472                 if (rt6_check_expired(rt))
1473                         continue;
1474                 if (rt->dst.error)
1475                         break;
1476                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1477                         continue;
1478                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1479                         continue;
1480                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1481                         continue;
1482                 break;
1483         }
1484
1485         if (!rt)
1486                 rt = net->ipv6.ip6_null_entry;
1487         else if (rt->dst.error) {
1488                 rt = net->ipv6.ip6_null_entry;
1489                 goto out;
1490         }
1491
1492         if (rt == net->ipv6.ip6_null_entry) {
1493                 fn = fib6_backtrack(fn, &fl6->saddr);
1494                 if (fn)
1495                         goto restart;
1496         }
1497
1498 out:
1499         dst_hold(&rt->dst);
1500
1501         read_unlock_bh(&table->tb6_lock);
1502
1503         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1504         return rt;
1505 };
1506
1507 static struct dst_entry *ip6_route_redirect(struct net *net,
1508                                         const struct flowi6 *fl6,
1509                                         const struct in6_addr *gateway)
1510 {
1511         int flags = RT6_LOOKUP_F_HAS_SADDR;
1512         struct ip6rd_flowi rdfl;
1513
1514         rdfl.fl6 = *fl6;
1515         rdfl.gateway = *gateway;
1516
1517         return fib6_rule_lookup(net, &rdfl.fl6,
1518                                 flags, __ip6_route_redirect);
1519 }
1520
1521 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1522 {
1523         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1524         struct dst_entry *dst;
1525         struct flowi6 fl6;
1526
1527         memset(&fl6, 0, sizeof(fl6));
1528         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1529         fl6.flowi6_oif = oif;
1530         fl6.flowi6_mark = mark;
1531         fl6.daddr = iph->daddr;
1532         fl6.saddr = iph->saddr;
1533         fl6.flowlabel = ip6_flowinfo(iph);
1534
1535         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1536         rt6_do_redirect(dst, NULL, skb);
1537         dst_release(dst);
1538 }
1539 EXPORT_SYMBOL_GPL(ip6_redirect);
1540
1541 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1542                             u32 mark)
1543 {
1544         const struct ipv6hdr *iph = ipv6_hdr(skb);
1545         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1546         struct dst_entry *dst;
1547         struct flowi6 fl6;
1548
1549         memset(&fl6, 0, sizeof(fl6));
1550         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1551         fl6.flowi6_oif = oif;
1552         fl6.flowi6_mark = mark;
1553         fl6.daddr = msg->dest;
1554         fl6.saddr = iph->daddr;
1555
1556         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1557         rt6_do_redirect(dst, NULL, skb);
1558         dst_release(dst);
1559 }
1560
1561 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1562 {
1563         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1564 }
1565 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1566
1567 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1568 {
1569         struct net_device *dev = dst->dev;
1570         unsigned int mtu = dst_mtu(dst);
1571         struct net *net = dev_net(dev);
1572
1573         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1574
1575         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1576                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1577
1578         /*
1579          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1580          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1581          * IPV6_MAXPLEN is also valid and means: "any MSS,
1582          * rely only on pmtu discovery"
1583          */
1584         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1585                 mtu = IPV6_MAXPLEN;
1586         return mtu;
1587 }
1588
1589 static unsigned int ip6_mtu(const struct dst_entry *dst)
1590 {
1591         const struct rt6_info *rt = (const struct rt6_info *)dst;
1592         unsigned int mtu = rt->rt6i_pmtu;
1593         struct inet6_dev *idev;
1594
1595         if (mtu)
1596                 goto out;
1597
1598         mtu = dst_metric_raw(dst, RTAX_MTU);
1599         if (mtu)
1600                 goto out;
1601
1602         mtu = IPV6_MIN_MTU;
1603
1604         rcu_read_lock();
1605         idev = __in6_dev_get(dst->dev);
1606         if (idev)
1607                 mtu = idev->cnf.mtu6;
1608         rcu_read_unlock();
1609
1610 out:
1611         mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
1612
1613         return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
1614 }
1615
1616 static struct dst_entry *icmp6_dst_gc_list;
1617 static DEFINE_SPINLOCK(icmp6_dst_lock);
1618
1619 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1620                                   struct flowi6 *fl6)
1621 {
1622         struct dst_entry *dst;
1623         struct rt6_info *rt;
1624         struct inet6_dev *idev = in6_dev_get(dev);
1625         struct net *net = dev_net(dev);
1626
1627         if (unlikely(!idev))
1628                 return ERR_PTR(-ENODEV);
1629
1630         rt = ip6_dst_alloc(net, dev, 0);
1631         if (unlikely(!rt)) {
1632                 in6_dev_put(idev);
1633                 dst = ERR_PTR(-ENOMEM);
1634                 goto out;
1635         }
1636
1637         rt->dst.flags |= DST_HOST;
1638         rt->dst.output  = ip6_output;
1639         atomic_set(&rt->dst.__refcnt, 1);
1640         rt->rt6i_gateway  = fl6->daddr;
1641         rt->rt6i_dst.addr = fl6->daddr;
1642         rt->rt6i_dst.plen = 128;
1643         rt->rt6i_idev     = idev;
1644         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1645
1646         spin_lock_bh(&icmp6_dst_lock);
1647         rt->dst.next = icmp6_dst_gc_list;
1648         icmp6_dst_gc_list = &rt->dst;
1649         spin_unlock_bh(&icmp6_dst_lock);
1650
1651         fib6_force_start_gc(net);
1652
1653         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1654
1655 out:
1656         return dst;
1657 }
1658
1659 int icmp6_dst_gc(void)
1660 {
1661         struct dst_entry *dst, **pprev;
1662         int more = 0;
1663
1664         spin_lock_bh(&icmp6_dst_lock);
1665         pprev = &icmp6_dst_gc_list;
1666
1667         while ((dst = *pprev) != NULL) {
1668                 if (!atomic_read(&dst->__refcnt)) {
1669                         *pprev = dst->next;
1670                         dst_free(dst);
1671                 } else {
1672                         pprev = &dst->next;
1673                         ++more;
1674                 }
1675         }
1676
1677         spin_unlock_bh(&icmp6_dst_lock);
1678
1679         return more;
1680 }
1681
1682 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1683                             void *arg)
1684 {
1685         struct dst_entry *dst, **pprev;
1686
1687         spin_lock_bh(&icmp6_dst_lock);
1688         pprev = &icmp6_dst_gc_list;
1689         while ((dst = *pprev) != NULL) {
1690                 struct rt6_info *rt = (struct rt6_info *) dst;
1691                 if (func(rt, arg)) {
1692                         *pprev = dst->next;
1693                         dst_free(dst);
1694                 } else {
1695                         pprev = &dst->next;
1696                 }
1697         }
1698         spin_unlock_bh(&icmp6_dst_lock);
1699 }
1700
1701 static int ip6_dst_gc(struct dst_ops *ops)
1702 {
1703         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1704         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1705         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1706         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1707         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1708         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1709         int entries;
1710
1711         entries = dst_entries_get_fast(ops);
1712         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1713             entries <= rt_max_size)
1714                 goto out;
1715
1716         net->ipv6.ip6_rt_gc_expire++;
1717         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1718         entries = dst_entries_get_slow(ops);
1719         if (entries < ops->gc_thresh)
1720                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1721 out:
1722         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1723         return entries > rt_max_size;
1724 }
1725
1726 static int ip6_convert_metrics(struct mx6_config *mxc,
1727                                const struct fib6_config *cfg)
1728 {
1729         bool ecn_ca = false;
1730         struct nlattr *nla;
1731         int remaining;
1732         u32 *mp;
1733
1734         if (!cfg->fc_mx)
1735                 return 0;
1736
1737         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1738         if (unlikely(!mp))
1739                 return -ENOMEM;
1740
1741         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1742                 int type = nla_type(nla);
1743                 u32 val;
1744
1745                 if (!type)
1746                         continue;
1747                 if (unlikely(type > RTAX_MAX))
1748                         goto err;
1749
1750                 if (type == RTAX_CC_ALGO) {
1751                         char tmp[TCP_CA_NAME_MAX];
1752
1753                         nla_strlcpy(tmp, nla, sizeof(tmp));
1754                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1755                         if (val == TCP_CA_UNSPEC)
1756                                 goto err;
1757                 } else {
1758                         val = nla_get_u32(nla);
1759                 }
1760                 if (type == RTAX_HOPLIMIT && val > 255)
1761                         val = 255;
1762                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1763                         goto err;
1764
1765                 mp[type - 1] = val;
1766                 __set_bit(type - 1, mxc->mx_valid);
1767         }
1768
1769         if (ecn_ca) {
1770                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1771                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1772         }
1773
1774         mxc->mx = mp;
1775         return 0;
1776  err:
1777         kfree(mp);
1778         return -EINVAL;
1779 }
1780
1781 static struct rt6_info *ip6_nh_lookup_table(struct net *net,
1782                                             struct fib6_config *cfg,
1783                                             const struct in6_addr *gw_addr)
1784 {
1785         struct flowi6 fl6 = {
1786                 .flowi6_oif = cfg->fc_ifindex,
1787                 .daddr = *gw_addr,
1788                 .saddr = cfg->fc_prefsrc,
1789         };
1790         struct fib6_table *table;
1791         struct rt6_info *rt;
1792         int flags = RT6_LOOKUP_F_IFACE;
1793
1794         table = fib6_get_table(net, cfg->fc_table);
1795         if (!table)
1796                 return NULL;
1797
1798         if (!ipv6_addr_any(&cfg->fc_prefsrc))
1799                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1800
1801         rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags);
1802
1803         /* if table lookup failed, fall back to full lookup */
1804         if (rt == net->ipv6.ip6_null_entry) {
1805                 ip6_rt_put(rt);
1806                 rt = NULL;
1807         }
1808
1809         return rt;
1810 }
1811
1812 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1813 {
1814         struct net *net = cfg->fc_nlinfo.nl_net;
1815         struct rt6_info *rt = NULL;
1816         struct net_device *dev = NULL;
1817         struct inet6_dev *idev = NULL;
1818         struct fib6_table *table;
1819         int addr_type;
1820         int err = -EINVAL;
1821
1822         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1823                 goto out;
1824 #ifndef CONFIG_IPV6_SUBTREES
1825         if (cfg->fc_src_len)
1826                 goto out;
1827 #endif
1828         if (cfg->fc_ifindex) {
1829                 err = -ENODEV;
1830                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1831                 if (!dev)
1832                         goto out;
1833                 idev = in6_dev_get(dev);
1834                 if (!idev)
1835                         goto out;
1836         }
1837
1838         if (cfg->fc_metric == 0)
1839                 cfg->fc_metric = IP6_RT_PRIO_USER;
1840
1841         err = -ENOBUFS;
1842         if (cfg->fc_nlinfo.nlh &&
1843             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1844                 table = fib6_get_table(net, cfg->fc_table);
1845                 if (!table) {
1846                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1847                         table = fib6_new_table(net, cfg->fc_table);
1848                 }
1849         } else {
1850                 table = fib6_new_table(net, cfg->fc_table);
1851         }
1852
1853         if (!table)
1854                 goto out;
1855
1856         rt = ip6_dst_alloc(net, NULL,
1857                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1858
1859         if (!rt) {
1860                 err = -ENOMEM;
1861                 goto out;
1862         }
1863
1864         if (cfg->fc_flags & RTF_EXPIRES)
1865                 rt6_set_expires(rt, jiffies +
1866                                 clock_t_to_jiffies(cfg->fc_expires));
1867         else
1868                 rt6_clean_expires(rt);
1869
1870         if (cfg->fc_protocol == RTPROT_UNSPEC)
1871                 cfg->fc_protocol = RTPROT_BOOT;
1872         rt->rt6i_protocol = cfg->fc_protocol;
1873
1874         addr_type = ipv6_addr_type(&cfg->fc_dst);
1875
1876         if (addr_type & IPV6_ADDR_MULTICAST)
1877                 rt->dst.input = ip6_mc_input;
1878         else if (cfg->fc_flags & RTF_LOCAL)
1879                 rt->dst.input = ip6_input;
1880         else
1881                 rt->dst.input = ip6_forward;
1882
1883         rt->dst.output = ip6_output;
1884
1885         if (cfg->fc_encap) {
1886                 struct lwtunnel_state *lwtstate;
1887
1888                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1889                                            cfg->fc_encap, AF_INET6, cfg,
1890                                            &lwtstate);
1891                 if (err)
1892                         goto out;
1893                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1894                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1895                         rt->dst.lwtstate->orig_output = rt->dst.output;
1896                         rt->dst.output = lwtunnel_output;
1897                 }
1898                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1899                         rt->dst.lwtstate->orig_input = rt->dst.input;
1900                         rt->dst.input = lwtunnel_input;
1901                 }
1902         }
1903
1904         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1905         rt->rt6i_dst.plen = cfg->fc_dst_len;
1906         if (rt->rt6i_dst.plen == 128)
1907                 rt->dst.flags |= DST_HOST;
1908
1909 #ifdef CONFIG_IPV6_SUBTREES
1910         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1911         rt->rt6i_src.plen = cfg->fc_src_len;
1912 #endif
1913
1914         rt->rt6i_metric = cfg->fc_metric;
1915
1916         /* We cannot add true routes via loopback here,
1917            they would result in kernel looping; promote them to reject routes
1918          */
1919         if ((cfg->fc_flags & RTF_REJECT) ||
1920             (dev && (dev->flags & IFF_LOOPBACK) &&
1921              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1922              !(cfg->fc_flags & RTF_LOCAL))) {
1923                 /* hold loopback dev/idev if we haven't done so. */
1924                 if (dev != net->loopback_dev) {
1925                         if (dev) {
1926                                 dev_put(dev);
1927                                 in6_dev_put(idev);
1928                         }
1929                         dev = net->loopback_dev;
1930                         dev_hold(dev);
1931                         idev = in6_dev_get(dev);
1932                         if (!idev) {
1933                                 err = -ENODEV;
1934                                 goto out;
1935                         }
1936                 }
1937                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1938                 switch (cfg->fc_type) {
1939                 case RTN_BLACKHOLE:
1940                         rt->dst.error = -EINVAL;
1941                         rt->dst.output = dst_discard_out;
1942                         rt->dst.input = dst_discard;
1943                         break;
1944                 case RTN_PROHIBIT:
1945                         rt->dst.error = -EACCES;
1946                         rt->dst.output = ip6_pkt_prohibit_out;
1947                         rt->dst.input = ip6_pkt_prohibit;
1948                         break;
1949                 case RTN_THROW:
1950                 case RTN_UNREACHABLE:
1951                 default:
1952                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1953                                         : (cfg->fc_type == RTN_UNREACHABLE)
1954                                         ? -EHOSTUNREACH : -ENETUNREACH;
1955                         rt->dst.output = ip6_pkt_discard_out;
1956                         rt->dst.input = ip6_pkt_discard;
1957                         break;
1958                 }
1959                 goto install_route;
1960         }
1961
1962         if (cfg->fc_flags & RTF_GATEWAY) {
1963                 const struct in6_addr *gw_addr;
1964                 int gwa_type;
1965
1966                 gw_addr = &cfg->fc_gateway;
1967                 gwa_type = ipv6_addr_type(gw_addr);
1968
1969                 /* if gw_addr is local we will fail to detect this in case
1970                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1971                  * will return already-added prefix route via interface that
1972                  * prefix route was assigned to, which might be non-loopback.
1973                  */
1974                 err = -EINVAL;
1975                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1976                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1977                                             dev : NULL, 0, 0))
1978                         goto out;
1979
1980                 rt->rt6i_gateway = *gw_addr;
1981
1982                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1983                         struct rt6_info *grt = NULL;
1984
1985                         /* IPv6 strictly inhibits using not link-local
1986                            addresses as nexthop address.
1987                            Otherwise, router will not able to send redirects.
1988                            It is very good, but in some (rare!) circumstances
1989                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1990                            some exceptions. --ANK
1991                          */
1992                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1993                                 goto out;
1994
1995                         if (cfg->fc_table)
1996                                 grt = ip6_nh_lookup_table(net, cfg, gw_addr);
1997
1998                         if (!grt)
1999                                 grt = rt6_lookup(net, gw_addr, NULL,
2000                                                  cfg->fc_ifindex, 1);
2001
2002                         err = -EHOSTUNREACH;
2003                         if (!grt)
2004                                 goto out;
2005                         if (dev) {
2006                                 if (dev != grt->dst.dev) {
2007                                         ip6_rt_put(grt);
2008                                         goto out;
2009                                 }
2010                         } else {
2011                                 dev = grt->dst.dev;
2012                                 idev = grt->rt6i_idev;
2013                                 dev_hold(dev);
2014                                 in6_dev_hold(grt->rt6i_idev);
2015                         }
2016                         if (!(grt->rt6i_flags & RTF_GATEWAY))
2017                                 err = 0;
2018                         ip6_rt_put(grt);
2019
2020                         if (err)
2021                                 goto out;
2022                 }
2023                 err = -EINVAL;
2024                 if (!dev || (dev->flags & IFF_LOOPBACK))
2025                         goto out;
2026         }
2027
2028         err = -ENODEV;
2029         if (!dev)
2030                 goto out;
2031
2032         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
2033                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
2034                         err = -EINVAL;
2035                         goto out;
2036                 }
2037                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
2038                 rt->rt6i_prefsrc.plen = 128;
2039         } else
2040                 rt->rt6i_prefsrc.plen = 0;
2041
2042         rt->rt6i_flags = cfg->fc_flags;
2043
2044 install_route:
2045         rt->dst.dev = dev;
2046         rt->rt6i_idev = idev;
2047         rt->rt6i_table = table;
2048
2049         cfg->fc_nlinfo.nl_net = dev_net(dev);
2050
2051         return rt;
2052 out:
2053         if (dev)
2054                 dev_put(dev);
2055         if (idev)
2056                 in6_dev_put(idev);
2057         if (rt)
2058                 dst_free(&rt->dst);
2059
2060         return ERR_PTR(err);
2061 }
2062
2063 int ip6_route_add(struct fib6_config *cfg)
2064 {
2065         struct mx6_config mxc = { .mx = NULL, };
2066         struct rt6_info *rt;
2067         int err;
2068
2069         rt = ip6_route_info_create(cfg);
2070         if (IS_ERR(rt)) {
2071                 err = PTR_ERR(rt);
2072                 rt = NULL;
2073                 goto out;
2074         }
2075
2076         err = ip6_convert_metrics(&mxc, cfg);
2077         if (err)
2078                 goto out;
2079
2080         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2081
2082         kfree(mxc.mx);
2083
2084         return err;
2085 out:
2086         if (rt)
2087                 dst_free(&rt->dst);
2088
2089         return err;
2090 }
2091
2092 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2093 {
2094         int err;
2095         struct fib6_table *table;
2096         struct net *net = dev_net(rt->dst.dev);
2097
2098         if (rt == net->ipv6.ip6_null_entry ||
2099             rt->dst.flags & DST_NOCACHE) {
2100                 err = -ENOENT;
2101                 goto out;
2102         }
2103
2104         table = rt->rt6i_table;
2105         write_lock_bh(&table->tb6_lock);
2106         err = fib6_del(rt, info);
2107         write_unlock_bh(&table->tb6_lock);
2108
2109 out:
2110         ip6_rt_put(rt);
2111         return err;
2112 }
2113
2114 int ip6_del_rt(struct rt6_info *rt)
2115 {
2116         struct nl_info info = {
2117                 .nl_net = dev_net(rt->dst.dev),
2118         };
2119         return __ip6_del_rt(rt, &info);
2120 }
2121
2122 static int ip6_route_del(struct fib6_config *cfg)
2123 {
2124         struct fib6_table *table;
2125         struct fib6_node *fn;
2126         struct rt6_info *rt;
2127         int err = -ESRCH;
2128
2129         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2130         if (!table)
2131                 return err;
2132
2133         read_lock_bh(&table->tb6_lock);
2134
2135         fn = fib6_locate(&table->tb6_root,
2136                          &cfg->fc_dst, cfg->fc_dst_len,
2137                          &cfg->fc_src, cfg->fc_src_len);
2138
2139         if (fn) {
2140                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2141                         if ((rt->rt6i_flags & RTF_CACHE) &&
2142                             !(cfg->fc_flags & RTF_CACHE))
2143                                 continue;
2144                         if (cfg->fc_ifindex &&
2145                             (!rt->dst.dev ||
2146                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2147                                 continue;
2148                         if (cfg->fc_flags & RTF_GATEWAY &&
2149                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2150                                 continue;
2151                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2152                                 continue;
2153                         dst_hold(&rt->dst);
2154                         read_unlock_bh(&table->tb6_lock);
2155
2156                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2157                 }
2158         }
2159         read_unlock_bh(&table->tb6_lock);
2160
2161         return err;
2162 }
2163
2164 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2165 {
2166         struct netevent_redirect netevent;
2167         struct rt6_info *rt, *nrt = NULL;
2168         struct ndisc_options ndopts;
2169         struct inet6_dev *in6_dev;
2170         struct neighbour *neigh;
2171         struct rd_msg *msg;
2172         int optlen, on_link;
2173         u8 *lladdr;
2174
2175         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2176         optlen -= sizeof(*msg);
2177
2178         if (optlen < 0) {
2179                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2180                 return;
2181         }
2182
2183         msg = (struct rd_msg *)icmp6_hdr(skb);
2184
2185         if (ipv6_addr_is_multicast(&msg->dest)) {
2186                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2187                 return;
2188         }
2189
2190         on_link = 0;
2191         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2192                 on_link = 1;
2193         } else if (ipv6_addr_type(&msg->target) !=
2194                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2195                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2196                 return;
2197         }
2198
2199         in6_dev = __in6_dev_get(skb->dev);
2200         if (!in6_dev)
2201                 return;
2202         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2203                 return;
2204
2205         /* RFC2461 8.1:
2206          *      The IP source address of the Redirect MUST be the same as the current
2207          *      first-hop router for the specified ICMP Destination Address.
2208          */
2209
2210         if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
2211                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2212                 return;
2213         }
2214
2215         lladdr = NULL;
2216         if (ndopts.nd_opts_tgt_lladdr) {
2217                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2218                                              skb->dev);
2219                 if (!lladdr) {
2220                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2221                         return;
2222                 }
2223         }
2224
2225         rt = (struct rt6_info *) dst;
2226         if (rt->rt6i_flags & RTF_REJECT) {
2227                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2228                 return;
2229         }
2230
2231         /* Redirect received -> path was valid.
2232          * Look, redirects are sent only in response to data packets,
2233          * so that this nexthop apparently is reachable. --ANK
2234          */
2235         dst_confirm(&rt->dst);
2236
2237         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2238         if (!neigh)
2239                 return;
2240
2241         /*
2242          *      We have finally decided to accept it.
2243          */
2244
2245         ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
2246                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2247                      NEIGH_UPDATE_F_OVERRIDE|
2248                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2249                                      NEIGH_UPDATE_F_ISROUTER)),
2250                      NDISC_REDIRECT, &ndopts);
2251
2252         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2253         if (!nrt)
2254                 goto out;
2255
2256         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2257         if (on_link)
2258                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2259
2260         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2261
2262         if (ip6_ins_rt(nrt))
2263                 goto out;
2264
2265         netevent.old = &rt->dst;
2266         netevent.new = &nrt->dst;
2267         netevent.daddr = &msg->dest;
2268         netevent.neigh = neigh;
2269         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2270
2271         if (rt->rt6i_flags & RTF_CACHE) {
2272                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2273                 ip6_del_rt(rt);
2274         }
2275
2276 out:
2277         neigh_release(neigh);
2278 }
2279
2280 /*
2281  *      Misc support functions
2282  */
2283
2284 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2285 {
2286         BUG_ON(from->dst.from);
2287
2288         rt->rt6i_flags &= ~RTF_EXPIRES;
2289         dst_hold(&from->dst);
2290         rt->dst.from = &from->dst;
2291         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2292 }
2293
2294 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2295 {
2296         rt->dst.input = ort->dst.input;
2297         rt->dst.output = ort->dst.output;
2298         rt->rt6i_dst = ort->rt6i_dst;
2299         rt->dst.error = ort->dst.error;
2300         rt->rt6i_idev = ort->rt6i_idev;
2301         if (rt->rt6i_idev)
2302                 in6_dev_hold(rt->rt6i_idev);
2303         rt->dst.lastuse = jiffies;
2304         rt->rt6i_gateway = ort->rt6i_gateway;
2305         rt->rt6i_flags = ort->rt6i_flags;
2306         rt6_set_from(rt, ort);
2307         rt->rt6i_metric = ort->rt6i_metric;
2308 #ifdef CONFIG_IPV6_SUBTREES
2309         rt->rt6i_src = ort->rt6i_src;
2310 #endif
2311         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2312         rt->rt6i_table = ort->rt6i_table;
2313         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2314 }
2315
2316 #ifdef CONFIG_IPV6_ROUTE_INFO
2317 static struct rt6_info *rt6_get_route_info(struct net *net,
2318                                            const struct in6_addr *prefix, int prefixlen,
2319                                            const struct in6_addr *gwaddr, int ifindex)
2320 {
2321         struct fib6_node *fn;
2322         struct rt6_info *rt = NULL;
2323         struct fib6_table *table;
2324
2325         table = fib6_get_table(net, RT6_TABLE_INFO);
2326         if (!table)
2327                 return NULL;
2328
2329         read_lock_bh(&table->tb6_lock);
2330         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2331         if (!fn)
2332                 goto out;
2333
2334         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2335                 if (rt->dst.dev->ifindex != ifindex)
2336                         continue;
2337                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2338                         continue;
2339                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2340                         continue;
2341                 dst_hold(&rt->dst);
2342                 break;
2343         }
2344 out:
2345         read_unlock_bh(&table->tb6_lock);
2346         return rt;
2347 }
2348
2349 static struct rt6_info *rt6_add_route_info(struct net *net,
2350                                            const struct in6_addr *prefix, int prefixlen,
2351                                            const struct in6_addr *gwaddr, int ifindex,
2352                                            unsigned int pref)
2353 {
2354         struct fib6_config cfg = {
2355                 .fc_metric      = IP6_RT_PRIO_USER,
2356                 .fc_ifindex     = ifindex,
2357                 .fc_dst_len     = prefixlen,
2358                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2359                                   RTF_UP | RTF_PREF(pref),
2360                 .fc_nlinfo.portid = 0,
2361                 .fc_nlinfo.nlh = NULL,
2362                 .fc_nlinfo.nl_net = net,
2363         };
2364
2365         cfg.fc_table = l3mdev_fib_table_by_index(net, ifindex) ? : RT6_TABLE_INFO;
2366         cfg.fc_dst = *prefix;
2367         cfg.fc_gateway = *gwaddr;
2368
2369         /* We should treat it as a default route if prefix length is 0. */
2370         if (!prefixlen)
2371                 cfg.fc_flags |= RTF_DEFAULT;
2372
2373         ip6_route_add(&cfg);
2374
2375         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2376 }
2377 #endif
2378
2379 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2380 {
2381         struct rt6_info *rt;
2382         struct fib6_table *table;
2383
2384         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2385         if (!table)
2386                 return NULL;
2387
2388         read_lock_bh(&table->tb6_lock);
2389         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2390                 if (dev == rt->dst.dev &&
2391                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2392                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2393                         break;
2394         }
2395         if (rt)
2396                 dst_hold(&rt->dst);
2397         read_unlock_bh(&table->tb6_lock);
2398         return rt;
2399 }
2400
2401 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2402                                      struct net_device *dev,
2403                                      unsigned int pref)
2404 {
2405         struct fib6_config cfg = {
2406                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2407                 .fc_metric      = IP6_RT_PRIO_USER,
2408                 .fc_ifindex     = dev->ifindex,
2409                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2410                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2411                 .fc_nlinfo.portid = 0,
2412                 .fc_nlinfo.nlh = NULL,
2413                 .fc_nlinfo.nl_net = dev_net(dev),
2414         };
2415
2416         cfg.fc_gateway = *gwaddr;
2417
2418         ip6_route_add(&cfg);
2419
2420         return rt6_get_dflt_router(gwaddr, dev);
2421 }
2422
2423 void rt6_purge_dflt_routers(struct net *net)
2424 {
2425         struct rt6_info *rt;
2426         struct fib6_table *table;
2427
2428         /* NOTE: Keep consistent with rt6_get_dflt_router */
2429         table = fib6_get_table(net, RT6_TABLE_DFLT);
2430         if (!table)
2431                 return;
2432
2433 restart:
2434         read_lock_bh(&table->tb6_lock);
2435         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2436                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2437                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2438                         dst_hold(&rt->dst);
2439                         read_unlock_bh(&table->tb6_lock);
2440                         ip6_del_rt(rt);
2441                         goto restart;
2442                 }
2443         }
2444         read_unlock_bh(&table->tb6_lock);
2445 }
2446
2447 static void rtmsg_to_fib6_config(struct net *net,
2448                                  struct in6_rtmsg *rtmsg,
2449                                  struct fib6_config *cfg)
2450 {
2451         memset(cfg, 0, sizeof(*cfg));
2452
2453         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2454                          : RT6_TABLE_MAIN;
2455         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2456         cfg->fc_metric = rtmsg->rtmsg_metric;
2457         cfg->fc_expires = rtmsg->rtmsg_info;
2458         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2459         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2460         cfg->fc_flags = rtmsg->rtmsg_flags;
2461
2462         cfg->fc_nlinfo.nl_net = net;
2463
2464         cfg->fc_dst = rtmsg->rtmsg_dst;
2465         cfg->fc_src = rtmsg->rtmsg_src;
2466         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2467 }
2468
2469 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2470 {
2471         struct fib6_config cfg;
2472         struct in6_rtmsg rtmsg;
2473         int err;
2474
2475         switch (cmd) {
2476         case SIOCADDRT:         /* Add a route */
2477         case SIOCDELRT:         /* Delete a route */
2478                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2479                         return -EPERM;
2480                 err = copy_from_user(&rtmsg, arg,
2481                                      sizeof(struct in6_rtmsg));
2482                 if (err)
2483                         return -EFAULT;
2484
2485                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2486
2487                 rtnl_lock();
2488                 switch (cmd) {
2489                 case SIOCADDRT:
2490                         err = ip6_route_add(&cfg);
2491                         break;
2492                 case SIOCDELRT:
2493                         err = ip6_route_del(&cfg);
2494                         break;
2495                 default:
2496                         err = -EINVAL;
2497                 }
2498                 rtnl_unlock();
2499
2500                 return err;
2501         }
2502
2503         return -EINVAL;
2504 }
2505
2506 /*
2507  *      Drop the packet on the floor
2508  */
2509
2510 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2511 {
2512         int type;
2513         struct dst_entry *dst = skb_dst(skb);
2514         switch (ipstats_mib_noroutes) {
2515         case IPSTATS_MIB_INNOROUTES:
2516                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2517                 if (type == IPV6_ADDR_ANY) {
2518                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2519                                       IPSTATS_MIB_INADDRERRORS);
2520                         break;
2521                 }
2522                 /* FALLTHROUGH */
2523         case IPSTATS_MIB_OUTNOROUTES:
2524                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2525                               ipstats_mib_noroutes);
2526                 break;
2527         }
2528         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2529         kfree_skb(skb);
2530         return 0;
2531 }
2532
2533 static int ip6_pkt_discard(struct sk_buff *skb)
2534 {
2535         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2536 }
2537
2538 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2539 {
2540         skb->dev = skb_dst(skb)->dev;
2541         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2542 }
2543
2544 static int ip6_pkt_prohibit(struct sk_buff *skb)
2545 {
2546         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2547 }
2548
2549 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2550 {
2551         skb->dev = skb_dst(skb)->dev;
2552         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2553 }
2554
2555 /*
2556  *      Allocate a dst for local (unicast / anycast) address.
2557  */
2558
2559 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2560                                     const struct in6_addr *addr,
2561                                     bool anycast)
2562 {
2563         u32 tb_id;
2564         struct net *net = dev_net(idev->dev);
2565         struct net_device *dev = net->loopback_dev;
2566         struct rt6_info *rt;
2567
2568         /* use L3 Master device as loopback for host routes if device
2569          * is enslaved and address is not link local or multicast
2570          */
2571         if (!rt6_need_strict(addr))
2572                 dev = l3mdev_master_dev_rcu(idev->dev) ? : dev;
2573
2574         rt = ip6_dst_alloc(net, dev, DST_NOCOUNT);
2575         if (!rt)
2576                 return ERR_PTR(-ENOMEM);
2577
2578         in6_dev_hold(idev);
2579
2580         rt->dst.flags |= DST_HOST;
2581         rt->dst.input = ip6_input;
2582         rt->dst.output = ip6_output;
2583         rt->rt6i_idev = idev;
2584
2585         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2586         if (anycast)
2587                 rt->rt6i_flags |= RTF_ANYCAST;
2588         else
2589                 rt->rt6i_flags |= RTF_LOCAL;
2590
2591         rt->rt6i_gateway  = *addr;
2592         rt->rt6i_dst.addr = *addr;
2593         rt->rt6i_dst.plen = 128;
2594         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2595         rt->rt6i_table = fib6_get_table(net, tb_id);
2596         rt->dst.flags |= DST_NOCACHE;
2597
2598         atomic_set(&rt->dst.__refcnt, 1);
2599
2600         return rt;
2601 }
2602
2603 /* remove deleted ip from prefsrc entries */
2604 struct arg_dev_net_ip {
2605         struct net_device *dev;
2606         struct net *net;
2607         struct in6_addr *addr;
2608 };
2609
2610 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2611 {
2612         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2613         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2614         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2615
2616         if (((void *)rt->dst.dev == dev || !dev) &&
2617             rt != net->ipv6.ip6_null_entry &&
2618             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2619                 /* remove prefsrc entry */
2620                 rt->rt6i_prefsrc.plen = 0;
2621         }
2622         return 0;
2623 }
2624
2625 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2626 {
2627         struct net *net = dev_net(ifp->idev->dev);
2628         struct arg_dev_net_ip adni = {
2629                 .dev = ifp->idev->dev,
2630                 .net = net,
2631                 .addr = &ifp->addr,
2632         };
2633         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2634 }
2635
2636 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2637 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2638
2639 /* Remove routers and update dst entries when gateway turn into host. */
2640 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2641 {
2642         struct in6_addr *gateway = (struct in6_addr *)arg;
2643
2644         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2645              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2646              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2647                 return -1;
2648         }
2649         return 0;
2650 }
2651
2652 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2653 {
2654         fib6_clean_all(net, fib6_clean_tohost, gateway);
2655 }
2656
2657 struct arg_dev_net {
2658         struct net_device *dev;
2659         struct net *net;
2660 };
2661
2662 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2663 {
2664         const struct arg_dev_net *adn = arg;
2665         const struct net_device *dev = adn->dev;
2666
2667         if ((rt->dst.dev == dev || !dev) &&
2668             rt != adn->net->ipv6.ip6_null_entry)
2669                 return -1;
2670
2671         return 0;
2672 }
2673
2674 void rt6_ifdown(struct net *net, struct net_device *dev)
2675 {
2676         struct arg_dev_net adn = {
2677                 .dev = dev,
2678                 .net = net,
2679         };
2680
2681         fib6_clean_all(net, fib6_ifdown, &adn);
2682         icmp6_clean_all(fib6_ifdown, &adn);
2683         if (dev)
2684                 rt6_uncached_list_flush_dev(net, dev);
2685 }
2686
2687 struct rt6_mtu_change_arg {
2688         struct net_device *dev;
2689         unsigned int mtu;
2690 };
2691
2692 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2693 {
2694         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2695         struct inet6_dev *idev;
2696
2697         /* In IPv6 pmtu discovery is not optional,
2698            so that RTAX_MTU lock cannot disable it.
2699            We still use this lock to block changes
2700            caused by addrconf/ndisc.
2701         */
2702
2703         idev = __in6_dev_get(arg->dev);
2704         if (!idev)
2705                 return 0;
2706
2707         /* For administrative MTU increase, there is no way to discover
2708            IPv6 PMTU increase, so PMTU increase should be updated here.
2709            Since RFC 1981 doesn't include administrative MTU increase
2710            update PMTU increase is a MUST. (i.e. jumbo frame)
2711          */
2712         /*
2713            If new MTU is less than route PMTU, this new MTU will be the
2714            lowest MTU in the path, update the route PMTU to reflect PMTU
2715            decreases; if new MTU is greater than route PMTU, and the
2716            old MTU is the lowest MTU in the path, update the route PMTU
2717            to reflect the increase. In this case if the other nodes' MTU
2718            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2719            PMTU discouvery.
2720          */
2721         if (rt->dst.dev == arg->dev &&
2722             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2723                 if (rt->rt6i_flags & RTF_CACHE) {
2724                         /* For RTF_CACHE with rt6i_pmtu == 0
2725                          * (i.e. a redirected route),
2726                          * the metrics of its rt->dst.from has already
2727                          * been updated.
2728                          */
2729                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2730                                 rt->rt6i_pmtu = arg->mtu;
2731                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2732                            (dst_mtu(&rt->dst) < arg->mtu &&
2733                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2734                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2735                 }
2736         }
2737         return 0;
2738 }
2739
2740 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2741 {
2742         struct rt6_mtu_change_arg arg = {
2743                 .dev = dev,
2744                 .mtu = mtu,
2745         };
2746
2747         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2748 }
2749
2750 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2751         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2752         [RTA_OIF]               = { .type = NLA_U32 },
2753         [RTA_IIF]               = { .type = NLA_U32 },
2754         [RTA_PRIORITY]          = { .type = NLA_U32 },
2755         [RTA_METRICS]           = { .type = NLA_NESTED },
2756         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2757         [RTA_PREF]              = { .type = NLA_U8 },
2758         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2759         [RTA_ENCAP]             = { .type = NLA_NESTED },
2760         [RTA_EXPIRES]           = { .type = NLA_U32 },
2761 };
2762
2763 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2764                               struct fib6_config *cfg)
2765 {
2766         struct rtmsg *rtm;
2767         struct nlattr *tb[RTA_MAX+1];
2768         unsigned int pref;
2769         int err;
2770
2771         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2772         if (err < 0)
2773                 goto errout;
2774
2775         err = -EINVAL;
2776         rtm = nlmsg_data(nlh);
2777         memset(cfg, 0, sizeof(*cfg));
2778
2779         cfg->fc_table = rtm->rtm_table;
2780         cfg->fc_dst_len = rtm->rtm_dst_len;
2781         cfg->fc_src_len = rtm->rtm_src_len;
2782         cfg->fc_flags = RTF_UP;
2783         cfg->fc_protocol = rtm->rtm_protocol;
2784         cfg->fc_type = rtm->rtm_type;
2785
2786         if (rtm->rtm_type == RTN_UNREACHABLE ||
2787             rtm->rtm_type == RTN_BLACKHOLE ||
2788             rtm->rtm_type == RTN_PROHIBIT ||
2789             rtm->rtm_type == RTN_THROW)
2790                 cfg->fc_flags |= RTF_REJECT;
2791
2792         if (rtm->rtm_type == RTN_LOCAL)
2793                 cfg->fc_flags |= RTF_LOCAL;
2794
2795         if (rtm->rtm_flags & RTM_F_CLONED)
2796                 cfg->fc_flags |= RTF_CACHE;
2797
2798         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2799         cfg->fc_nlinfo.nlh = nlh;
2800         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2801
2802         if (tb[RTA_GATEWAY]) {
2803                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2804                 cfg->fc_flags |= RTF_GATEWAY;
2805         }
2806
2807         if (tb[RTA_DST]) {
2808                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2809
2810                 if (nla_len(tb[RTA_DST]) < plen)
2811                         goto errout;
2812
2813                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2814         }
2815
2816         if (tb[RTA_SRC]) {
2817                 int plen = (rtm->rtm_src_len + 7) >> 3;
2818
2819                 if (nla_len(tb[RTA_SRC]) < plen)
2820                         goto errout;
2821
2822                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2823         }
2824
2825         if (tb[RTA_PREFSRC])
2826                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2827
2828         if (tb[RTA_OIF])
2829                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2830
2831         if (tb[RTA_PRIORITY])
2832                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2833
2834         if (tb[RTA_METRICS]) {
2835                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2836                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2837         }
2838
2839         if (tb[RTA_TABLE])
2840                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2841
2842         if (tb[RTA_MULTIPATH]) {
2843                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2844                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2845         }
2846
2847         if (tb[RTA_PREF]) {
2848                 pref = nla_get_u8(tb[RTA_PREF]);
2849                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2850                     pref != ICMPV6_ROUTER_PREF_HIGH)
2851                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2852                 cfg->fc_flags |= RTF_PREF(pref);
2853         }
2854
2855         if (tb[RTA_ENCAP])
2856                 cfg->fc_encap = tb[RTA_ENCAP];
2857
2858         if (tb[RTA_ENCAP_TYPE])
2859                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2860
2861         if (tb[RTA_EXPIRES]) {
2862                 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
2863
2864                 if (addrconf_finite_timeout(timeout)) {
2865                         cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
2866                         cfg->fc_flags |= RTF_EXPIRES;
2867                 }
2868         }
2869
2870         err = 0;
2871 errout:
2872         return err;
2873 }
2874
2875 struct rt6_nh {
2876         struct rt6_info *rt6_info;
2877         struct fib6_config r_cfg;
2878         struct mx6_config mxc;
2879         struct list_head next;
2880 };
2881
2882 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2883 {
2884         struct rt6_nh *nh;
2885
2886         list_for_each_entry(nh, rt6_nh_list, next) {
2887                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2888                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2889                         nh->r_cfg.fc_ifindex);
2890         }
2891 }
2892
2893 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2894                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2895 {
2896         struct rt6_nh *nh;
2897         struct rt6_info *rtnh;
2898         int err = -EEXIST;
2899
2900         list_for_each_entry(nh, rt6_nh_list, next) {
2901                 /* check if rt6_info already exists */
2902                 rtnh = nh->rt6_info;
2903
2904                 if (rtnh->dst.dev == rt->dst.dev &&
2905                     rtnh->rt6i_idev == rt->rt6i_idev &&
2906                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2907                                     &rt->rt6i_gateway))
2908                         return err;
2909         }
2910
2911         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2912         if (!nh)
2913                 return -ENOMEM;
2914         nh->rt6_info = rt;
2915         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2916         if (err) {
2917                 kfree(nh);
2918                 return err;
2919         }
2920         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2921         list_add_tail(&nh->next, rt6_nh_list);
2922
2923         return 0;
2924 }
2925
2926 static int ip6_route_multipath_add(struct fib6_config *cfg)
2927 {
2928         struct fib6_config r_cfg;
2929         struct rtnexthop *rtnh;
2930         struct rt6_info *rt;
2931         struct rt6_nh *err_nh;
2932         struct rt6_nh *nh, *nh_safe;
2933         int remaining;
2934         int attrlen;
2935         int err = 1;
2936         int nhn = 0;
2937         int replace = (cfg->fc_nlinfo.nlh &&
2938                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2939         LIST_HEAD(rt6_nh_list);
2940
2941         remaining = cfg->fc_mp_len;
2942         rtnh = (struct rtnexthop *)cfg->fc_mp;
2943
2944         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2945          * rt6_info structs per nexthop
2946          */
2947         while (rtnh_ok(rtnh, remaining)) {
2948                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2949                 if (rtnh->rtnh_ifindex)
2950                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2951
2952                 attrlen = rtnh_attrlen(rtnh);
2953                 if (attrlen > 0) {
2954                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2955
2956                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2957                         if (nla) {
2958                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2959                                 r_cfg.fc_flags |= RTF_GATEWAY;
2960                         }
2961                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2962                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2963                         if (nla)
2964                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2965                 }
2966
2967                 rt = ip6_route_info_create(&r_cfg);
2968                 if (IS_ERR(rt)) {
2969                         err = PTR_ERR(rt);
2970                         rt = NULL;
2971                         goto cleanup;
2972                 }
2973
2974                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2975                 if (err) {
2976                         dst_free(&rt->dst);
2977                         goto cleanup;
2978                 }
2979
2980                 rtnh = rtnh_next(rtnh, &remaining);
2981         }
2982
2983         err_nh = NULL;
2984         list_for_each_entry(nh, &rt6_nh_list, next) {
2985                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2986                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2987                 nh->rt6_info = NULL;
2988                 if (err) {
2989                         if (replace && nhn)
2990                                 ip6_print_replace_route_err(&rt6_nh_list);
2991                         err_nh = nh;
2992                         goto add_errout;
2993                 }
2994
2995                 /* Because each route is added like a single route we remove
2996                  * these flags after the first nexthop: if there is a collision,
2997                  * we have already failed to add the first nexthop:
2998                  * fib6_add_rt2node() has rejected it; when replacing, old
2999                  * nexthops have been replaced by first new, the rest should
3000                  * be added to it.
3001                  */
3002                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
3003                                                      NLM_F_REPLACE);
3004                 nhn++;
3005         }
3006
3007         goto cleanup;
3008
3009 add_errout:
3010         /* Delete routes that were already added */
3011         list_for_each_entry(nh, &rt6_nh_list, next) {
3012                 if (err_nh == nh)
3013                         break;
3014                 ip6_route_del(&nh->r_cfg);
3015         }
3016
3017 cleanup:
3018         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
3019                 if (nh->rt6_info)
3020                         dst_free(&nh->rt6_info->dst);
3021                 kfree(nh->mxc.mx);
3022                 list_del(&nh->next);
3023                 kfree(nh);
3024         }
3025
3026         return err;
3027 }
3028
3029 static int ip6_route_multipath_del(struct fib6_config *cfg)
3030 {
3031         struct fib6_config r_cfg;
3032         struct rtnexthop *rtnh;
3033         int remaining;
3034         int attrlen;
3035         int err = 1, last_err = 0;
3036
3037         remaining = cfg->fc_mp_len;
3038         rtnh = (struct rtnexthop *)cfg->fc_mp;
3039
3040         /* Parse a Multipath Entry */
3041         while (rtnh_ok(rtnh, remaining)) {
3042                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3043                 if (rtnh->rtnh_ifindex)
3044                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3045
3046                 attrlen = rtnh_attrlen(rtnh);
3047                 if (attrlen > 0) {
3048                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3049
3050                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3051                         if (nla) {
3052                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3053                                 r_cfg.fc_flags |= RTF_GATEWAY;
3054                         }
3055                 }
3056                 err = ip6_route_del(&r_cfg);
3057                 if (err)
3058                         last_err = err;
3059
3060                 rtnh = rtnh_next(rtnh, &remaining);
3061         }
3062
3063         return last_err;
3064 }
3065
3066 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3067 {
3068         struct fib6_config cfg;
3069         int err;
3070
3071         err = rtm_to_fib6_config(skb, nlh, &cfg);
3072         if (err < 0)
3073                 return err;
3074
3075         if (cfg.fc_mp)
3076                 return ip6_route_multipath_del(&cfg);
3077         else
3078                 return ip6_route_del(&cfg);
3079 }
3080
3081 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3082 {
3083         struct fib6_config cfg;
3084         int err;
3085
3086         err = rtm_to_fib6_config(skb, nlh, &cfg);
3087         if (err < 0)
3088                 return err;
3089
3090         if (cfg.fc_mp)
3091                 return ip6_route_multipath_add(&cfg);
3092         else
3093                 return ip6_route_add(&cfg);
3094 }
3095
3096 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3097 {
3098         return NLMSG_ALIGN(sizeof(struct rtmsg))
3099                + nla_total_size(16) /* RTA_SRC */
3100                + nla_total_size(16) /* RTA_DST */
3101                + nla_total_size(16) /* RTA_GATEWAY */
3102                + nla_total_size(16) /* RTA_PREFSRC */
3103                + nla_total_size(4) /* RTA_TABLE */
3104                + nla_total_size(4) /* RTA_IIF */
3105                + nla_total_size(4) /* RTA_OIF */
3106                + nla_total_size(4) /* RTA_PRIORITY */
3107                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3108                + nla_total_size(sizeof(struct rta_cacheinfo))
3109                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3110                + nla_total_size(1) /* RTA_PREF */
3111                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3112 }
3113
3114 static int rt6_fill_node(struct net *net,
3115                          struct sk_buff *skb, struct rt6_info *rt,
3116                          struct in6_addr *dst, struct in6_addr *src,
3117                          int iif, int type, u32 portid, u32 seq,
3118                          int prefix, int nowait, unsigned int flags)
3119 {
3120         u32 metrics[RTAX_MAX];
3121         struct rtmsg *rtm;
3122         struct nlmsghdr *nlh;
3123         long expires;
3124         u32 table;
3125
3126         if (prefix) {   /* user wants prefix routes only */
3127                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3128                         /* success since this is not a prefix route */
3129                         return 1;
3130                 }
3131         }
3132
3133         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3134         if (!nlh)
3135                 return -EMSGSIZE;
3136
3137         rtm = nlmsg_data(nlh);
3138         rtm->rtm_family = AF_INET6;
3139         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3140         rtm->rtm_src_len = rt->rt6i_src.plen;
3141         rtm->rtm_tos = 0;
3142         if (rt->rt6i_table)
3143                 table = rt->rt6i_table->tb6_id;
3144         else
3145                 table = RT6_TABLE_UNSPEC;
3146         rtm->rtm_table = table;
3147         if (nla_put_u32(skb, RTA_TABLE, table))
3148                 goto nla_put_failure;
3149         if (rt->rt6i_flags & RTF_REJECT) {
3150                 switch (rt->dst.error) {
3151                 case -EINVAL:
3152                         rtm->rtm_type = RTN_BLACKHOLE;
3153                         break;
3154                 case -EACCES:
3155                         rtm->rtm_type = RTN_PROHIBIT;
3156                         break;
3157                 case -EAGAIN:
3158                         rtm->rtm_type = RTN_THROW;
3159                         break;
3160                 default:
3161                         rtm->rtm_type = RTN_UNREACHABLE;
3162                         break;
3163                 }
3164         }
3165         else if (rt->rt6i_flags & RTF_LOCAL)
3166                 rtm->rtm_type = RTN_LOCAL;
3167         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3168                 rtm->rtm_type = RTN_LOCAL;
3169         else
3170                 rtm->rtm_type = RTN_UNICAST;
3171         rtm->rtm_flags = 0;
3172         if (!netif_carrier_ok(rt->dst.dev)) {
3173                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3174                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3175                         rtm->rtm_flags |= RTNH_F_DEAD;
3176         }
3177         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3178         rtm->rtm_protocol = rt->rt6i_protocol;
3179         if (rt->rt6i_flags & RTF_DYNAMIC)
3180                 rtm->rtm_protocol = RTPROT_REDIRECT;
3181         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3182                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3183                         rtm->rtm_protocol = RTPROT_RA;
3184                 else
3185                         rtm->rtm_protocol = RTPROT_KERNEL;
3186         }
3187
3188         if (rt->rt6i_flags & RTF_CACHE)
3189                 rtm->rtm_flags |= RTM_F_CLONED;
3190
3191         if (dst) {
3192                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3193                         goto nla_put_failure;
3194                 rtm->rtm_dst_len = 128;
3195         } else if (rtm->rtm_dst_len)
3196                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3197                         goto nla_put_failure;
3198 #ifdef CONFIG_IPV6_SUBTREES
3199         if (src) {
3200                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3201                         goto nla_put_failure;
3202                 rtm->rtm_src_len = 128;
3203         } else if (rtm->rtm_src_len &&
3204                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3205                 goto nla_put_failure;
3206 #endif
3207         if (iif) {
3208 #ifdef CONFIG_IPV6_MROUTE
3209                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3210                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3211                         if (err <= 0) {
3212                                 if (!nowait) {
3213                                         if (err == 0)
3214                                                 return 0;
3215                                         goto nla_put_failure;
3216                                 } else {
3217                                         if (err == -EMSGSIZE)
3218                                                 goto nla_put_failure;
3219                                 }
3220                         }
3221                 } else
3222 #endif
3223                         if (nla_put_u32(skb, RTA_IIF, iif))
3224                                 goto nla_put_failure;
3225         } else if (dst) {
3226                 struct in6_addr saddr_buf;
3227                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3228                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3229                         goto nla_put_failure;
3230         }
3231
3232         if (rt->rt6i_prefsrc.plen) {
3233                 struct in6_addr saddr_buf;
3234                 saddr_buf = rt->rt6i_prefsrc.addr;
3235                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3236                         goto nla_put_failure;
3237         }
3238
3239         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3240         if (rt->rt6i_pmtu)
3241                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3242         if (rtnetlink_put_metrics(skb, metrics) < 0)
3243                 goto nla_put_failure;
3244
3245         if (rt->rt6i_flags & RTF_GATEWAY) {
3246                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3247                         goto nla_put_failure;
3248         }
3249
3250         if (rt->dst.dev &&
3251             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3252                 goto nla_put_failure;
3253         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3254                 goto nla_put_failure;
3255
3256         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3257
3258         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3259                 goto nla_put_failure;
3260
3261         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3262                 goto nla_put_failure;
3263
3264         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3265
3266         nlmsg_end(skb, nlh);
3267         return 0;
3268
3269 nla_put_failure:
3270         nlmsg_cancel(skb, nlh);
3271         return -EMSGSIZE;
3272 }
3273
3274 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3275 {
3276         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3277         int prefix;
3278
3279         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3280                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3281                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3282         } else
3283                 prefix = 0;
3284
3285         return rt6_fill_node(arg->net,
3286                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3287                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3288                      prefix, 0, NLM_F_MULTI);
3289 }
3290
3291 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3292 {
3293         struct net *net = sock_net(in_skb->sk);
3294         struct nlattr *tb[RTA_MAX+1];
3295         struct rt6_info *rt;
3296         struct sk_buff *skb;
3297         struct rtmsg *rtm;
3298         struct flowi6 fl6;
3299         int err, iif = 0, oif = 0;
3300
3301         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3302         if (err < 0)
3303                 goto errout;
3304
3305         err = -EINVAL;
3306         memset(&fl6, 0, sizeof(fl6));
3307         rtm = nlmsg_data(nlh);
3308         fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
3309
3310         if (tb[RTA_SRC]) {
3311                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3312                         goto errout;
3313
3314                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3315         }
3316
3317         if (tb[RTA_DST]) {
3318                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3319                         goto errout;
3320
3321                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3322         }
3323
3324         if (tb[RTA_IIF])
3325                 iif = nla_get_u32(tb[RTA_IIF]);
3326
3327         if (tb[RTA_OIF])
3328                 oif = nla_get_u32(tb[RTA_OIF]);
3329
3330         if (tb[RTA_MARK])
3331                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3332
3333         if (iif) {
3334                 struct net_device *dev;
3335                 int flags = 0;
3336
3337                 dev = __dev_get_by_index(net, iif);
3338                 if (!dev) {
3339                         err = -ENODEV;
3340                         goto errout;
3341                 }
3342
3343                 fl6.flowi6_iif = iif;
3344
3345                 if (!ipv6_addr_any(&fl6.saddr))
3346                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3347
3348                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3349                                                                flags);
3350         } else {
3351                 fl6.flowi6_oif = oif;
3352
3353                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3354         }
3355
3356         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3357         if (!skb) {
3358                 ip6_rt_put(rt);
3359                 err = -ENOBUFS;
3360                 goto errout;
3361         }
3362
3363         /* Reserve room for dummy headers, this skb can pass
3364            through good chunk of routing engine.
3365          */
3366         skb_reset_mac_header(skb);
3367         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3368
3369         skb_dst_set(skb, &rt->dst);
3370
3371         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3372                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3373                             nlh->nlmsg_seq, 0, 0, 0);
3374         if (err < 0) {
3375                 kfree_skb(skb);
3376                 goto errout;
3377         }
3378
3379         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3380 errout:
3381         return err;
3382 }
3383
3384 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3385                      unsigned int nlm_flags)
3386 {
3387         struct sk_buff *skb;
3388         struct net *net = info->nl_net;
3389         u32 seq;
3390         int err;
3391
3392         err = -ENOBUFS;
3393         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3394
3395         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3396         if (!skb)
3397                 goto errout;
3398
3399         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3400                                 event, info->portid, seq, 0, 0, nlm_flags);
3401         if (err < 0) {
3402                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3403                 WARN_ON(err == -EMSGSIZE);
3404                 kfree_skb(skb);
3405                 goto errout;
3406         }
3407         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3408                     info->nlh, gfp_any());
3409         return;
3410 errout:
3411         if (err < 0)
3412                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3413 }
3414
3415 static int ip6_route_dev_notify(struct notifier_block *this,
3416                                 unsigned long event, void *ptr)
3417 {
3418         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3419         struct net *net = dev_net(dev);
3420
3421         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3422                 net->ipv6.ip6_null_entry->dst.dev = dev;
3423                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3424 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3425                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3426                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3427                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3428                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3429 #endif
3430         }
3431
3432         return NOTIFY_OK;
3433 }
3434
3435 /*
3436  *      /proc
3437  */
3438
3439 #ifdef CONFIG_PROC_FS
3440
3441 static const struct file_operations ipv6_route_proc_fops = {
3442         .owner          = THIS_MODULE,
3443         .open           = ipv6_route_open,
3444         .read           = seq_read,
3445         .llseek         = seq_lseek,
3446         .release        = seq_release_net,
3447 };
3448
3449 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3450 {
3451         struct net *net = (struct net *)seq->private;
3452         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3453                    net->ipv6.rt6_stats->fib_nodes,
3454                    net->ipv6.rt6_stats->fib_route_nodes,
3455                    net->ipv6.rt6_stats->fib_rt_alloc,
3456                    net->ipv6.rt6_stats->fib_rt_entries,
3457                    net->ipv6.rt6_stats->fib_rt_cache,
3458                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3459                    net->ipv6.rt6_stats->fib_discarded_routes);
3460
3461         return 0;
3462 }
3463
3464 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3465 {
3466         return single_open_net(inode, file, rt6_stats_seq_show);
3467 }
3468
3469 static const struct file_operations rt6_stats_seq_fops = {
3470         .owner   = THIS_MODULE,
3471         .open    = rt6_stats_seq_open,
3472         .read    = seq_read,
3473         .llseek  = seq_lseek,
3474         .release = single_release_net,
3475 };
3476 #endif  /* CONFIG_PROC_FS */
3477
3478 #ifdef CONFIG_SYSCTL
3479
3480 static
3481 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3482                               void __user *buffer, size_t *lenp, loff_t *ppos)
3483 {
3484         struct net *net;
3485         int delay;
3486         if (!write)
3487                 return -EINVAL;
3488
3489         net = (struct net *)ctl->extra1;
3490         delay = net->ipv6.sysctl.flush_delay;
3491         proc_dointvec(ctl, write, buffer, lenp, ppos);
3492         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3493         return 0;
3494 }
3495
3496 struct ctl_table ipv6_route_table_template[] = {
3497         {
3498                 .procname       =       "flush",
3499                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3500                 .maxlen         =       sizeof(int),
3501                 .mode           =       0200,
3502                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3503         },
3504         {
3505                 .procname       =       "gc_thresh",
3506                 .data           =       &ip6_dst_ops_template.gc_thresh,
3507                 .maxlen         =       sizeof(int),
3508                 .mode           =       0644,
3509                 .proc_handler   =       proc_dointvec,
3510         },
3511         {
3512                 .procname       =       "max_size",
3513                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3514                 .maxlen         =       sizeof(int),
3515                 .mode           =       0644,
3516                 .proc_handler   =       proc_dointvec,
3517         },
3518         {
3519                 .procname       =       "gc_min_interval",
3520                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3521                 .maxlen         =       sizeof(int),
3522                 .mode           =       0644,
3523                 .proc_handler   =       proc_dointvec_jiffies,
3524         },
3525         {
3526                 .procname       =       "gc_timeout",
3527                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3528                 .maxlen         =       sizeof(int),
3529                 .mode           =       0644,
3530                 .proc_handler   =       proc_dointvec_jiffies,
3531         },
3532         {
3533                 .procname       =       "gc_interval",
3534                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3535                 .maxlen         =       sizeof(int),
3536                 .mode           =       0644,
3537                 .proc_handler   =       proc_dointvec_jiffies,
3538         },
3539         {
3540                 .procname       =       "gc_elasticity",
3541                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3542                 .maxlen         =       sizeof(int),
3543                 .mode           =       0644,
3544                 .proc_handler   =       proc_dointvec,
3545         },
3546         {
3547                 .procname       =       "mtu_expires",
3548                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3549                 .maxlen         =       sizeof(int),
3550                 .mode           =       0644,
3551                 .proc_handler   =       proc_dointvec_jiffies,
3552         },
3553         {
3554                 .procname       =       "min_adv_mss",
3555                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3556                 .maxlen         =       sizeof(int),
3557                 .mode           =       0644,
3558                 .proc_handler   =       proc_dointvec,
3559         },
3560         {
3561                 .procname       =       "gc_min_interval_ms",
3562                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3563                 .maxlen         =       sizeof(int),
3564                 .mode           =       0644,
3565                 .proc_handler   =       proc_dointvec_ms_jiffies,
3566         },
3567         { }
3568 };
3569
3570 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3571 {
3572         struct ctl_table *table;
3573
3574         table = kmemdup(ipv6_route_table_template,
3575                         sizeof(ipv6_route_table_template),
3576                         GFP_KERNEL);
3577
3578         if (table) {
3579                 table[0].data = &net->ipv6.sysctl.flush_delay;
3580                 table[0].extra1 = net;
3581                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3582                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3583                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3584                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3585                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3586                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3587                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3588                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3589                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3590
3591                 /* Don't export sysctls to unprivileged users */
3592                 if (net->user_ns != &init_user_ns)
3593                         table[0].procname = NULL;
3594         }
3595
3596         return table;
3597 }
3598 #endif
3599
3600 static int __net_init ip6_route_net_init(struct net *net)
3601 {
3602         int ret = -ENOMEM;
3603
3604         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3605                sizeof(net->ipv6.ip6_dst_ops));
3606
3607         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3608                 goto out_ip6_dst_ops;
3609
3610         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3611                                            sizeof(*net->ipv6.ip6_null_entry),
3612                                            GFP_KERNEL);
3613         if (!net->ipv6.ip6_null_entry)
3614                 goto out_ip6_dst_entries;
3615         net->ipv6.ip6_null_entry->dst.path =
3616                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3617         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3618         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3619                          ip6_template_metrics, true);
3620
3621 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3622         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3623                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3624                                                GFP_KERNEL);
3625         if (!net->ipv6.ip6_prohibit_entry)
3626                 goto out_ip6_null_entry;
3627         net->ipv6.ip6_prohibit_entry->dst.path =
3628                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3629         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3630         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3631                          ip6_template_metrics, true);
3632
3633         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3634                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3635                                                GFP_KERNEL);
3636         if (!net->ipv6.ip6_blk_hole_entry)
3637                 goto out_ip6_prohibit_entry;
3638         net->ipv6.ip6_blk_hole_entry->dst.path =
3639                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3640         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3641         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3642                          ip6_template_metrics, true);
3643 #endif
3644
3645         net->ipv6.sysctl.flush_delay = 0;
3646         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3647         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3648         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3649         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3650         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3651         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3652         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3653
3654         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3655
3656         ret = 0;
3657 out:
3658         return ret;
3659
3660 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3661 out_ip6_prohibit_entry:
3662         kfree(net->ipv6.ip6_prohibit_entry);
3663 out_ip6_null_entry:
3664         kfree(net->ipv6.ip6_null_entry);
3665 #endif
3666 out_ip6_dst_entries:
3667         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3668 out_ip6_dst_ops:
3669         goto out;
3670 }
3671
3672 static void __net_exit ip6_route_net_exit(struct net *net)
3673 {
3674         kfree(net->ipv6.ip6_null_entry);
3675 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3676         kfree(net->ipv6.ip6_prohibit_entry);
3677         kfree(net->ipv6.ip6_blk_hole_entry);
3678 #endif
3679         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3680 }
3681
3682 static int __net_init ip6_route_net_init_late(struct net *net)
3683 {
3684 #ifdef CONFIG_PROC_FS
3685         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3686         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3687 #endif
3688         return 0;
3689 }
3690
3691 static void __net_exit ip6_route_net_exit_late(struct net *net)
3692 {
3693 #ifdef CONFIG_PROC_FS
3694         remove_proc_entry("ipv6_route", net->proc_net);
3695         remove_proc_entry("rt6_stats", net->proc_net);
3696 #endif
3697 }
3698
3699 static struct pernet_operations ip6_route_net_ops = {
3700         .init = ip6_route_net_init,
3701         .exit = ip6_route_net_exit,
3702 };
3703
3704 static int __net_init ipv6_inetpeer_init(struct net *net)
3705 {
3706         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3707
3708         if (!bp)
3709                 return -ENOMEM;
3710         inet_peer_base_init(bp);
3711         net->ipv6.peers = bp;
3712         return 0;
3713 }
3714
3715 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3716 {
3717         struct inet_peer_base *bp = net->ipv6.peers;
3718
3719         net->ipv6.peers = NULL;
3720         inetpeer_invalidate_tree(bp);
3721         kfree(bp);
3722 }
3723
3724 static struct pernet_operations ipv6_inetpeer_ops = {
3725         .init   =       ipv6_inetpeer_init,
3726         .exit   =       ipv6_inetpeer_exit,
3727 };
3728
3729 static struct pernet_operations ip6_route_net_late_ops = {
3730         .init = ip6_route_net_init_late,
3731         .exit = ip6_route_net_exit_late,
3732 };
3733
3734 static struct notifier_block ip6_route_dev_notifier = {
3735         .notifier_call = ip6_route_dev_notify,
3736         .priority = 0,
3737 };
3738
3739 int __init ip6_route_init(void)
3740 {
3741         int ret;
3742         int cpu;
3743
3744         ret = -ENOMEM;
3745         ip6_dst_ops_template.kmem_cachep =
3746                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3747                                   SLAB_HWCACHE_ALIGN, NULL);
3748         if (!ip6_dst_ops_template.kmem_cachep)
3749                 goto out;
3750
3751         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3752         if (ret)
3753                 goto out_kmem_cache;
3754
3755         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3756         if (ret)
3757                 goto out_dst_entries;
3758
3759         ret = register_pernet_subsys(&ip6_route_net_ops);
3760         if (ret)
3761                 goto out_register_inetpeer;
3762
3763         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3764
3765         /* Registering of the loopback is done before this portion of code,
3766          * the loopback reference in rt6_info will not be taken, do it
3767          * manually for init_net */
3768         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3769         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3770   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3771         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3772         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3773         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3774         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3775   #endif
3776         ret = fib6_init();
3777         if (ret)
3778                 goto out_register_subsys;
3779
3780         ret = xfrm6_init();
3781         if (ret)
3782                 goto out_fib6_init;
3783
3784         ret = fib6_rules_init();
3785         if (ret)
3786                 goto xfrm6_init;
3787
3788         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3789         if (ret)
3790                 goto fib6_rules_init;
3791
3792         ret = -ENOBUFS;
3793         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3794             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3795             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3796                 goto out_register_late_subsys;
3797
3798         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3799         if (ret)
3800                 goto out_register_late_subsys;
3801
3802         for_each_possible_cpu(cpu) {
3803                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3804
3805                 INIT_LIST_HEAD(&ul->head);
3806                 spin_lock_init(&ul->lock);
3807         }
3808
3809 out:
3810         return ret;
3811
3812 out_register_late_subsys:
3813         unregister_pernet_subsys(&ip6_route_net_late_ops);
3814 fib6_rules_init:
3815         fib6_rules_cleanup();
3816 xfrm6_init:
3817         xfrm6_fini();
3818 out_fib6_init:
3819         fib6_gc_cleanup();
3820 out_register_subsys:
3821         unregister_pernet_subsys(&ip6_route_net_ops);
3822 out_register_inetpeer:
3823         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3824 out_dst_entries:
3825         dst_entries_destroy(&ip6_dst_blackhole_ops);
3826 out_kmem_cache:
3827         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3828         goto out;
3829 }
3830
3831 void ip6_route_cleanup(void)
3832 {
3833         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3834         unregister_pernet_subsys(&ip6_route_net_late_ops);
3835         fib6_rules_cleanup();
3836         xfrm6_fini();
3837         fib6_gc_cleanup();
3838         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3839         unregister_pernet_subsys(&ip6_route_net_ops);
3840         dst_entries_destroy(&ip6_dst_blackhole_ops);
3841         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3842 }