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 static 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
1160 void ip6_route_input(struct sk_buff *skb)
1161 {
1162         const struct ipv6hdr *iph = ipv6_hdr(skb);
1163         struct net *net = dev_net(skb->dev);
1164         int flags = RT6_LOOKUP_F_HAS_SADDR;
1165         struct ip_tunnel_info *tun_info;
1166         struct flowi6 fl6 = {
1167                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1168                 .daddr = iph->daddr,
1169                 .saddr = iph->saddr,
1170                 .flowlabel = ip6_flowinfo(iph),
1171                 .flowi6_mark = skb->mark,
1172                 .flowi6_proto = iph->nexthdr,
1173         };
1174
1175         tun_info = skb_tunnel_info(skb);
1176         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1177                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1178         skb_dst_drop(skb);
1179         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1180 }
1181
1182 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1183                                              struct flowi6 *fl6, int flags)
1184 {
1185         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1186 }
1187
1188 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1189                                          struct flowi6 *fl6, int flags)
1190 {
1191         struct dst_entry *dst;
1192         bool any_src;
1193
1194         dst = l3mdev_get_rt6_dst(net, fl6);
1195         if (dst)
1196                 return dst;
1197
1198         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1199
1200         any_src = ipv6_addr_any(&fl6->saddr);
1201         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1202             (fl6->flowi6_oif && any_src))
1203                 flags |= RT6_LOOKUP_F_IFACE;
1204
1205         if (!any_src)
1206                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1207         else if (sk)
1208                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1209
1210         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1211 }
1212 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1213
1214 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1215 {
1216         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1217         struct dst_entry *new = NULL;
1218
1219         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1220         if (rt) {
1221                 rt6_info_init(rt);
1222
1223                 new = &rt->dst;
1224                 new->__use = 1;
1225                 new->input = dst_discard;
1226                 new->output = dst_discard_out;
1227
1228                 dst_copy_metrics(new, &ort->dst);
1229                 rt->rt6i_idev = ort->rt6i_idev;
1230                 if (rt->rt6i_idev)
1231                         in6_dev_hold(rt->rt6i_idev);
1232
1233                 rt->rt6i_gateway = ort->rt6i_gateway;
1234                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1235                 rt->rt6i_metric = 0;
1236
1237                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1238 #ifdef CONFIG_IPV6_SUBTREES
1239                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1240 #endif
1241
1242                 dst_free(new);
1243         }
1244
1245         dst_release(dst_orig);
1246         return new ? new : ERR_PTR(-ENOMEM);
1247 }
1248
1249 /*
1250  *      Destination cache support functions
1251  */
1252
1253 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1254 {
1255         if (rt->dst.from &&
1256             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1257                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1258 }
1259
1260 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1261 {
1262         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1263                 return NULL;
1264
1265         if (rt6_check_expired(rt))
1266                 return NULL;
1267
1268         return &rt->dst;
1269 }
1270
1271 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1272 {
1273         if (!__rt6_check_expired(rt) &&
1274             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1275             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1276                 return &rt->dst;
1277         else
1278                 return NULL;
1279 }
1280
1281 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1282 {
1283         struct rt6_info *rt;
1284
1285         rt = (struct rt6_info *) dst;
1286
1287         /* All IPV6 dsts are created with ->obsolete set to the value
1288          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1289          * into this function always.
1290          */
1291
1292         rt6_dst_from_metrics_check(rt);
1293
1294         if (rt->rt6i_flags & RTF_PCPU ||
1295             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1296                 return rt6_dst_from_check(rt, cookie);
1297         else
1298                 return rt6_check(rt, cookie);
1299 }
1300
1301 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1302 {
1303         struct rt6_info *rt = (struct rt6_info *) dst;
1304
1305         if (rt) {
1306                 if (rt->rt6i_flags & RTF_CACHE) {
1307                         if (rt6_check_expired(rt)) {
1308                                 ip6_del_rt(rt);
1309                                 dst = NULL;
1310                         }
1311                 } else {
1312                         dst_release(dst);
1313                         dst = NULL;
1314                 }
1315         }
1316         return dst;
1317 }
1318
1319 static void ip6_link_failure(struct sk_buff *skb)
1320 {
1321         struct rt6_info *rt;
1322
1323         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1324
1325         rt = (struct rt6_info *) skb_dst(skb);
1326         if (rt) {
1327                 if (rt->rt6i_flags & RTF_CACHE) {
1328                         dst_hold(&rt->dst);
1329                         ip6_del_rt(rt);
1330                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1331                         rt->rt6i_node->fn_sernum = -1;
1332                 }
1333         }
1334 }
1335
1336 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1337 {
1338         struct net *net = dev_net(rt->dst.dev);
1339
1340         rt->rt6i_flags |= RTF_MODIFIED;
1341         rt->rt6i_pmtu = mtu;
1342         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1343 }
1344
1345 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1346 {
1347         return !(rt->rt6i_flags & RTF_CACHE) &&
1348                 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1349 }
1350
1351 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1352                                  const struct ipv6hdr *iph, u32 mtu)
1353 {
1354         struct rt6_info *rt6 = (struct rt6_info *)dst;
1355
1356         if (rt6->rt6i_flags & RTF_LOCAL)
1357                 return;
1358
1359         dst_confirm(dst);
1360         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1361         if (mtu >= dst_mtu(dst))
1362                 return;
1363
1364         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1365                 rt6_do_update_pmtu(rt6, mtu);
1366         } else {
1367                 const struct in6_addr *daddr, *saddr;
1368                 struct rt6_info *nrt6;
1369
1370                 if (iph) {
1371                         daddr = &iph->daddr;
1372                         saddr = &iph->saddr;
1373                 } else if (sk) {
1374                         daddr = &sk->sk_v6_daddr;
1375                         saddr = &inet6_sk(sk)->saddr;
1376                 } else {
1377                         return;
1378                 }
1379                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1380                 if (nrt6) {
1381                         rt6_do_update_pmtu(nrt6, mtu);
1382
1383                         /* ip6_ins_rt(nrt6) will bump the
1384                          * rt6->rt6i_node->fn_sernum
1385                          * which will fail the next rt6_check() and
1386                          * invalidate the sk->sk_dst_cache.
1387                          */
1388                         ip6_ins_rt(nrt6);
1389                 }
1390         }
1391 }
1392
1393 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1394                                struct sk_buff *skb, u32 mtu)
1395 {
1396         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1397 }
1398
1399 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1400                      int oif, u32 mark)
1401 {
1402         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1403         struct dst_entry *dst;
1404         struct flowi6 fl6;
1405
1406         memset(&fl6, 0, sizeof(fl6));
1407         fl6.flowi6_oif = oif;
1408         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1409         fl6.daddr = iph->daddr;
1410         fl6.saddr = iph->saddr;
1411         fl6.flowlabel = ip6_flowinfo(iph);
1412
1413         dst = ip6_route_output(net, NULL, &fl6);
1414         if (!dst->error)
1415                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1416         dst_release(dst);
1417 }
1418 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1419
1420 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1421 {
1422         struct dst_entry *dst;
1423
1424         ip6_update_pmtu(skb, sock_net(sk), mtu,
1425                         sk->sk_bound_dev_if, sk->sk_mark);
1426
1427         dst = __sk_dst_get(sk);
1428         if (!dst || !dst->obsolete ||
1429             dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
1430                 return;
1431
1432         bh_lock_sock(sk);
1433         if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1434                 ip6_datagram_dst_update(sk, false);
1435         bh_unlock_sock(sk);
1436 }
1437 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1438
1439 /* Handle redirects */
1440 struct ip6rd_flowi {
1441         struct flowi6 fl6;
1442         struct in6_addr gateway;
1443 };
1444
1445 static struct rt6_info *__ip6_route_redirect(struct net *net,
1446                                              struct fib6_table *table,
1447                                              struct flowi6 *fl6,
1448                                              int flags)
1449 {
1450         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1451         struct rt6_info *rt;
1452         struct fib6_node *fn;
1453
1454         /* Get the "current" route for this destination and
1455          * check if the redirect has come from approriate router.
1456          *
1457          * RFC 4861 specifies that redirects should only be
1458          * accepted if they come from the nexthop to the target.
1459          * Due to the way the routes are chosen, this notion
1460          * is a bit fuzzy and one might need to check all possible
1461          * routes.
1462          */
1463
1464         read_lock_bh(&table->tb6_lock);
1465         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1466 restart:
1467         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1468                 if (rt6_check_expired(rt))
1469                         continue;
1470                 if (rt->dst.error)
1471                         break;
1472                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1473                         continue;
1474                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1475                         continue;
1476                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1477                         continue;
1478                 break;
1479         }
1480
1481         if (!rt)
1482                 rt = net->ipv6.ip6_null_entry;
1483         else if (rt->dst.error) {
1484                 rt = net->ipv6.ip6_null_entry;
1485                 goto out;
1486         }
1487
1488         if (rt == net->ipv6.ip6_null_entry) {
1489                 fn = fib6_backtrack(fn, &fl6->saddr);
1490                 if (fn)
1491                         goto restart;
1492         }
1493
1494 out:
1495         dst_hold(&rt->dst);
1496
1497         read_unlock_bh(&table->tb6_lock);
1498
1499         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1500         return rt;
1501 };
1502
1503 static struct dst_entry *ip6_route_redirect(struct net *net,
1504                                         const struct flowi6 *fl6,
1505                                         const struct in6_addr *gateway)
1506 {
1507         int flags = RT6_LOOKUP_F_HAS_SADDR;
1508         struct ip6rd_flowi rdfl;
1509
1510         rdfl.fl6 = *fl6;
1511         rdfl.gateway = *gateway;
1512
1513         return fib6_rule_lookup(net, &rdfl.fl6,
1514                                 flags, __ip6_route_redirect);
1515 }
1516
1517 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1518 {
1519         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1520         struct dst_entry *dst;
1521         struct flowi6 fl6;
1522
1523         memset(&fl6, 0, sizeof(fl6));
1524         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1525         fl6.flowi6_oif = oif;
1526         fl6.flowi6_mark = mark;
1527         fl6.daddr = iph->daddr;
1528         fl6.saddr = iph->saddr;
1529         fl6.flowlabel = ip6_flowinfo(iph);
1530
1531         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1532         rt6_do_redirect(dst, NULL, skb);
1533         dst_release(dst);
1534 }
1535 EXPORT_SYMBOL_GPL(ip6_redirect);
1536
1537 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1538                             u32 mark)
1539 {
1540         const struct ipv6hdr *iph = ipv6_hdr(skb);
1541         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1542         struct dst_entry *dst;
1543         struct flowi6 fl6;
1544
1545         memset(&fl6, 0, sizeof(fl6));
1546         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1547         fl6.flowi6_oif = oif;
1548         fl6.flowi6_mark = mark;
1549         fl6.daddr = msg->dest;
1550         fl6.saddr = iph->daddr;
1551
1552         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1553         rt6_do_redirect(dst, NULL, skb);
1554         dst_release(dst);
1555 }
1556
1557 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1558 {
1559         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1560 }
1561 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1562
1563 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1564 {
1565         struct net_device *dev = dst->dev;
1566         unsigned int mtu = dst_mtu(dst);
1567         struct net *net = dev_net(dev);
1568
1569         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1570
1571         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1572                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1573
1574         /*
1575          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1576          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1577          * IPV6_MAXPLEN is also valid and means: "any MSS,
1578          * rely only on pmtu discovery"
1579          */
1580         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1581                 mtu = IPV6_MAXPLEN;
1582         return mtu;
1583 }
1584
1585 static unsigned int ip6_mtu(const struct dst_entry *dst)
1586 {
1587         const struct rt6_info *rt = (const struct rt6_info *)dst;
1588         unsigned int mtu = rt->rt6i_pmtu;
1589         struct inet6_dev *idev;
1590
1591         if (mtu)
1592                 goto out;
1593
1594         mtu = dst_metric_raw(dst, RTAX_MTU);
1595         if (mtu)
1596                 goto out;
1597
1598         mtu = IPV6_MIN_MTU;
1599
1600         rcu_read_lock();
1601         idev = __in6_dev_get(dst->dev);
1602         if (idev)
1603                 mtu = idev->cnf.mtu6;
1604         rcu_read_unlock();
1605
1606 out:
1607         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1608 }
1609
1610 static struct dst_entry *icmp6_dst_gc_list;
1611 static DEFINE_SPINLOCK(icmp6_dst_lock);
1612
1613 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1614                                   struct flowi6 *fl6)
1615 {
1616         struct dst_entry *dst;
1617         struct rt6_info *rt;
1618         struct inet6_dev *idev = in6_dev_get(dev);
1619         struct net *net = dev_net(dev);
1620
1621         if (unlikely(!idev))
1622                 return ERR_PTR(-ENODEV);
1623
1624         rt = ip6_dst_alloc(net, dev, 0);
1625         if (unlikely(!rt)) {
1626                 in6_dev_put(idev);
1627                 dst = ERR_PTR(-ENOMEM);
1628                 goto out;
1629         }
1630
1631         rt->dst.flags |= DST_HOST;
1632         rt->dst.output  = ip6_output;
1633         atomic_set(&rt->dst.__refcnt, 1);
1634         rt->rt6i_gateway  = fl6->daddr;
1635         rt->rt6i_dst.addr = fl6->daddr;
1636         rt->rt6i_dst.plen = 128;
1637         rt->rt6i_idev     = idev;
1638         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1639
1640         spin_lock_bh(&icmp6_dst_lock);
1641         rt->dst.next = icmp6_dst_gc_list;
1642         icmp6_dst_gc_list = &rt->dst;
1643         spin_unlock_bh(&icmp6_dst_lock);
1644
1645         fib6_force_start_gc(net);
1646
1647         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1648
1649 out:
1650         return dst;
1651 }
1652
1653 int icmp6_dst_gc(void)
1654 {
1655         struct dst_entry *dst, **pprev;
1656         int more = 0;
1657
1658         spin_lock_bh(&icmp6_dst_lock);
1659         pprev = &icmp6_dst_gc_list;
1660
1661         while ((dst = *pprev) != NULL) {
1662                 if (!atomic_read(&dst->__refcnt)) {
1663                         *pprev = dst->next;
1664                         dst_free(dst);
1665                 } else {
1666                         pprev = &dst->next;
1667                         ++more;
1668                 }
1669         }
1670
1671         spin_unlock_bh(&icmp6_dst_lock);
1672
1673         return more;
1674 }
1675
1676 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1677                             void *arg)
1678 {
1679         struct dst_entry *dst, **pprev;
1680
1681         spin_lock_bh(&icmp6_dst_lock);
1682         pprev = &icmp6_dst_gc_list;
1683         while ((dst = *pprev) != NULL) {
1684                 struct rt6_info *rt = (struct rt6_info *) dst;
1685                 if (func(rt, arg)) {
1686                         *pprev = dst->next;
1687                         dst_free(dst);
1688                 } else {
1689                         pprev = &dst->next;
1690                 }
1691         }
1692         spin_unlock_bh(&icmp6_dst_lock);
1693 }
1694
1695 static int ip6_dst_gc(struct dst_ops *ops)
1696 {
1697         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1698         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1699         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1700         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1701         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1702         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1703         int entries;
1704
1705         entries = dst_entries_get_fast(ops);
1706         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1707             entries <= rt_max_size)
1708                 goto out;
1709
1710         net->ipv6.ip6_rt_gc_expire++;
1711         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1712         entries = dst_entries_get_slow(ops);
1713         if (entries < ops->gc_thresh)
1714                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1715 out:
1716         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1717         return entries > rt_max_size;
1718 }
1719
1720 static int ip6_convert_metrics(struct mx6_config *mxc,
1721                                const struct fib6_config *cfg)
1722 {
1723         bool ecn_ca = false;
1724         struct nlattr *nla;
1725         int remaining;
1726         u32 *mp;
1727
1728         if (!cfg->fc_mx)
1729                 return 0;
1730
1731         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1732         if (unlikely(!mp))
1733                 return -ENOMEM;
1734
1735         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1736                 int type = nla_type(nla);
1737                 u32 val;
1738
1739                 if (!type)
1740                         continue;
1741                 if (unlikely(type > RTAX_MAX))
1742                         goto err;
1743
1744                 if (type == RTAX_CC_ALGO) {
1745                         char tmp[TCP_CA_NAME_MAX];
1746
1747                         nla_strlcpy(tmp, nla, sizeof(tmp));
1748                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1749                         if (val == TCP_CA_UNSPEC)
1750                                 goto err;
1751                 } else {
1752                         val = nla_get_u32(nla);
1753                 }
1754                 if (type == RTAX_HOPLIMIT && val > 255)
1755                         val = 255;
1756                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1757                         goto err;
1758
1759                 mp[type - 1] = val;
1760                 __set_bit(type - 1, mxc->mx_valid);
1761         }
1762
1763         if (ecn_ca) {
1764                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1765                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1766         }
1767
1768         mxc->mx = mp;
1769         return 0;
1770  err:
1771         kfree(mp);
1772         return -EINVAL;
1773 }
1774
1775 static struct rt6_info *ip6_nh_lookup_table(struct net *net,
1776                                             struct fib6_config *cfg,
1777                                             const struct in6_addr *gw_addr)
1778 {
1779         struct flowi6 fl6 = {
1780                 .flowi6_oif = cfg->fc_ifindex,
1781                 .daddr = *gw_addr,
1782                 .saddr = cfg->fc_prefsrc,
1783         };
1784         struct fib6_table *table;
1785         struct rt6_info *rt;
1786         int flags = RT6_LOOKUP_F_IFACE;
1787
1788         table = fib6_get_table(net, cfg->fc_table);
1789         if (!table)
1790                 return NULL;
1791
1792         if (!ipv6_addr_any(&cfg->fc_prefsrc))
1793                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1794
1795         rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags);
1796
1797         /* if table lookup failed, fall back to full lookup */
1798         if (rt == net->ipv6.ip6_null_entry) {
1799                 ip6_rt_put(rt);
1800                 rt = NULL;
1801         }
1802
1803         return rt;
1804 }
1805
1806 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1807 {
1808         struct net *net = cfg->fc_nlinfo.nl_net;
1809         struct rt6_info *rt = NULL;
1810         struct net_device *dev = NULL;
1811         struct inet6_dev *idev = NULL;
1812         struct fib6_table *table;
1813         int addr_type;
1814         int err = -EINVAL;
1815
1816         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1817                 goto out;
1818 #ifndef CONFIG_IPV6_SUBTREES
1819         if (cfg->fc_src_len)
1820                 goto out;
1821 #endif
1822         if (cfg->fc_ifindex) {
1823                 err = -ENODEV;
1824                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1825                 if (!dev)
1826                         goto out;
1827                 idev = in6_dev_get(dev);
1828                 if (!idev)
1829                         goto out;
1830         }
1831
1832         if (cfg->fc_metric == 0)
1833                 cfg->fc_metric = IP6_RT_PRIO_USER;
1834
1835         err = -ENOBUFS;
1836         if (cfg->fc_nlinfo.nlh &&
1837             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1838                 table = fib6_get_table(net, cfg->fc_table);
1839                 if (!table) {
1840                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1841                         table = fib6_new_table(net, cfg->fc_table);
1842                 }
1843         } else {
1844                 table = fib6_new_table(net, cfg->fc_table);
1845         }
1846
1847         if (!table)
1848                 goto out;
1849
1850         rt = ip6_dst_alloc(net, NULL,
1851                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1852
1853         if (!rt) {
1854                 err = -ENOMEM;
1855                 goto out;
1856         }
1857
1858         if (cfg->fc_flags & RTF_EXPIRES)
1859                 rt6_set_expires(rt, jiffies +
1860                                 clock_t_to_jiffies(cfg->fc_expires));
1861         else
1862                 rt6_clean_expires(rt);
1863
1864         if (cfg->fc_protocol == RTPROT_UNSPEC)
1865                 cfg->fc_protocol = RTPROT_BOOT;
1866         rt->rt6i_protocol = cfg->fc_protocol;
1867
1868         addr_type = ipv6_addr_type(&cfg->fc_dst);
1869
1870         if (addr_type & IPV6_ADDR_MULTICAST)
1871                 rt->dst.input = ip6_mc_input;
1872         else if (cfg->fc_flags & RTF_LOCAL)
1873                 rt->dst.input = ip6_input;
1874         else
1875                 rt->dst.input = ip6_forward;
1876
1877         rt->dst.output = ip6_output;
1878
1879         if (cfg->fc_encap) {
1880                 struct lwtunnel_state *lwtstate;
1881
1882                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1883                                            cfg->fc_encap, AF_INET6, cfg,
1884                                            &lwtstate);
1885                 if (err)
1886                         goto out;
1887                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1888                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1889                         rt->dst.lwtstate->orig_output = rt->dst.output;
1890                         rt->dst.output = lwtunnel_output;
1891                 }
1892                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1893                         rt->dst.lwtstate->orig_input = rt->dst.input;
1894                         rt->dst.input = lwtunnel_input;
1895                 }
1896         }
1897
1898         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1899         rt->rt6i_dst.plen = cfg->fc_dst_len;
1900         if (rt->rt6i_dst.plen == 128)
1901                 rt->dst.flags |= DST_HOST;
1902
1903 #ifdef CONFIG_IPV6_SUBTREES
1904         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1905         rt->rt6i_src.plen = cfg->fc_src_len;
1906 #endif
1907
1908         rt->rt6i_metric = cfg->fc_metric;
1909
1910         /* We cannot add true routes via loopback here,
1911            they would result in kernel looping; promote them to reject routes
1912          */
1913         if ((cfg->fc_flags & RTF_REJECT) ||
1914             (dev && (dev->flags & IFF_LOOPBACK) &&
1915              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1916              !(cfg->fc_flags & RTF_LOCAL))) {
1917                 /* hold loopback dev/idev if we haven't done so. */
1918                 if (dev != net->loopback_dev) {
1919                         if (dev) {
1920                                 dev_put(dev);
1921                                 in6_dev_put(idev);
1922                         }
1923                         dev = net->loopback_dev;
1924                         dev_hold(dev);
1925                         idev = in6_dev_get(dev);
1926                         if (!idev) {
1927                                 err = -ENODEV;
1928                                 goto out;
1929                         }
1930                 }
1931                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1932                 switch (cfg->fc_type) {
1933                 case RTN_BLACKHOLE:
1934                         rt->dst.error = -EINVAL;
1935                         rt->dst.output = dst_discard_out;
1936                         rt->dst.input = dst_discard;
1937                         break;
1938                 case RTN_PROHIBIT:
1939                         rt->dst.error = -EACCES;
1940                         rt->dst.output = ip6_pkt_prohibit_out;
1941                         rt->dst.input = ip6_pkt_prohibit;
1942                         break;
1943                 case RTN_THROW:
1944                 case RTN_UNREACHABLE:
1945                 default:
1946                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1947                                         : (cfg->fc_type == RTN_UNREACHABLE)
1948                                         ? -EHOSTUNREACH : -ENETUNREACH;
1949                         rt->dst.output = ip6_pkt_discard_out;
1950                         rt->dst.input = ip6_pkt_discard;
1951                         break;
1952                 }
1953                 goto install_route;
1954         }
1955
1956         if (cfg->fc_flags & RTF_GATEWAY) {
1957                 const struct in6_addr *gw_addr;
1958                 int gwa_type;
1959
1960                 gw_addr = &cfg->fc_gateway;
1961                 gwa_type = ipv6_addr_type(gw_addr);
1962
1963                 /* if gw_addr is local we will fail to detect this in case
1964                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1965                  * will return already-added prefix route via interface that
1966                  * prefix route was assigned to, which might be non-loopback.
1967                  */
1968                 err = -EINVAL;
1969                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1970                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1971                                             dev : NULL, 0, 0))
1972                         goto out;
1973
1974                 rt->rt6i_gateway = *gw_addr;
1975
1976                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1977                         struct rt6_info *grt = NULL;
1978
1979                         /* IPv6 strictly inhibits using not link-local
1980                            addresses as nexthop address.
1981                            Otherwise, router will not able to send redirects.
1982                            It is very good, but in some (rare!) circumstances
1983                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1984                            some exceptions. --ANK
1985                          */
1986                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1987                                 goto out;
1988
1989                         if (cfg->fc_table)
1990                                 grt = ip6_nh_lookup_table(net, cfg, gw_addr);
1991
1992                         if (!grt)
1993                                 grt = rt6_lookup(net, gw_addr, NULL,
1994                                                  cfg->fc_ifindex, 1);
1995
1996                         err = -EHOSTUNREACH;
1997                         if (!grt)
1998                                 goto out;
1999                         if (dev) {
2000                                 if (dev != grt->dst.dev) {
2001                                         ip6_rt_put(grt);
2002                                         goto out;
2003                                 }
2004                         } else {
2005                                 dev = grt->dst.dev;
2006                                 idev = grt->rt6i_idev;
2007                                 dev_hold(dev);
2008                                 in6_dev_hold(grt->rt6i_idev);
2009                         }
2010                         if (!(grt->rt6i_flags & RTF_GATEWAY))
2011                                 err = 0;
2012                         ip6_rt_put(grt);
2013
2014                         if (err)
2015                                 goto out;
2016                 }
2017                 err = -EINVAL;
2018                 if (!dev || (dev->flags & IFF_LOOPBACK))
2019                         goto out;
2020         }
2021
2022         err = -ENODEV;
2023         if (!dev)
2024                 goto out;
2025
2026         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
2027                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
2028                         err = -EINVAL;
2029                         goto out;
2030                 }
2031                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
2032                 rt->rt6i_prefsrc.plen = 128;
2033         } else
2034                 rt->rt6i_prefsrc.plen = 0;
2035
2036         rt->rt6i_flags = cfg->fc_flags;
2037
2038 install_route:
2039         rt->dst.dev = dev;
2040         rt->rt6i_idev = idev;
2041         rt->rt6i_table = table;
2042
2043         cfg->fc_nlinfo.nl_net = dev_net(dev);
2044
2045         return rt;
2046 out:
2047         if (dev)
2048                 dev_put(dev);
2049         if (idev)
2050                 in6_dev_put(idev);
2051         if (rt)
2052                 dst_free(&rt->dst);
2053
2054         return ERR_PTR(err);
2055 }
2056
2057 int ip6_route_add(struct fib6_config *cfg)
2058 {
2059         struct mx6_config mxc = { .mx = NULL, };
2060         struct rt6_info *rt;
2061         int err;
2062
2063         rt = ip6_route_info_create(cfg);
2064         if (IS_ERR(rt)) {
2065                 err = PTR_ERR(rt);
2066                 rt = NULL;
2067                 goto out;
2068         }
2069
2070         err = ip6_convert_metrics(&mxc, cfg);
2071         if (err)
2072                 goto out;
2073
2074         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2075
2076         kfree(mxc.mx);
2077
2078         return err;
2079 out:
2080         if (rt)
2081                 dst_free(&rt->dst);
2082
2083         return err;
2084 }
2085
2086 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2087 {
2088         int err;
2089         struct fib6_table *table;
2090         struct net *net = dev_net(rt->dst.dev);
2091
2092         if (rt == net->ipv6.ip6_null_entry ||
2093             rt->dst.flags & DST_NOCACHE) {
2094                 err = -ENOENT;
2095                 goto out;
2096         }
2097
2098         table = rt->rt6i_table;
2099         write_lock_bh(&table->tb6_lock);
2100         err = fib6_del(rt, info);
2101         write_unlock_bh(&table->tb6_lock);
2102
2103 out:
2104         ip6_rt_put(rt);
2105         return err;
2106 }
2107
2108 int ip6_del_rt(struct rt6_info *rt)
2109 {
2110         struct nl_info info = {
2111                 .nl_net = dev_net(rt->dst.dev),
2112         };
2113         return __ip6_del_rt(rt, &info);
2114 }
2115
2116 static int ip6_route_del(struct fib6_config *cfg)
2117 {
2118         struct fib6_table *table;
2119         struct fib6_node *fn;
2120         struct rt6_info *rt;
2121         int err = -ESRCH;
2122
2123         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2124         if (!table)
2125                 return err;
2126
2127         read_lock_bh(&table->tb6_lock);
2128
2129         fn = fib6_locate(&table->tb6_root,
2130                          &cfg->fc_dst, cfg->fc_dst_len,
2131                          &cfg->fc_src, cfg->fc_src_len);
2132
2133         if (fn) {
2134                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2135                         if ((rt->rt6i_flags & RTF_CACHE) &&
2136                             !(cfg->fc_flags & RTF_CACHE))
2137                                 continue;
2138                         if (cfg->fc_ifindex &&
2139                             (!rt->dst.dev ||
2140                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2141                                 continue;
2142                         if (cfg->fc_flags & RTF_GATEWAY &&
2143                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2144                                 continue;
2145                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2146                                 continue;
2147                         dst_hold(&rt->dst);
2148                         read_unlock_bh(&table->tb6_lock);
2149
2150                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2151                 }
2152         }
2153         read_unlock_bh(&table->tb6_lock);
2154
2155         return err;
2156 }
2157
2158 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2159 {
2160         struct netevent_redirect netevent;
2161         struct rt6_info *rt, *nrt = NULL;
2162         struct ndisc_options ndopts;
2163         struct inet6_dev *in6_dev;
2164         struct neighbour *neigh;
2165         struct rd_msg *msg;
2166         int optlen, on_link;
2167         u8 *lladdr;
2168
2169         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2170         optlen -= sizeof(*msg);
2171
2172         if (optlen < 0) {
2173                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2174                 return;
2175         }
2176
2177         msg = (struct rd_msg *)icmp6_hdr(skb);
2178
2179         if (ipv6_addr_is_multicast(&msg->dest)) {
2180                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2181                 return;
2182         }
2183
2184         on_link = 0;
2185         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2186                 on_link = 1;
2187         } else if (ipv6_addr_type(&msg->target) !=
2188                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2189                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2190                 return;
2191         }
2192
2193         in6_dev = __in6_dev_get(skb->dev);
2194         if (!in6_dev)
2195                 return;
2196         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2197                 return;
2198
2199         /* RFC2461 8.1:
2200          *      The IP source address of the Redirect MUST be the same as the current
2201          *      first-hop router for the specified ICMP Destination Address.
2202          */
2203
2204         if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
2205                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2206                 return;
2207         }
2208
2209         lladdr = NULL;
2210         if (ndopts.nd_opts_tgt_lladdr) {
2211                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2212                                              skb->dev);
2213                 if (!lladdr) {
2214                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2215                         return;
2216                 }
2217         }
2218
2219         rt = (struct rt6_info *) dst;
2220         if (rt->rt6i_flags & RTF_REJECT) {
2221                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2222                 return;
2223         }
2224
2225         /* Redirect received -> path was valid.
2226          * Look, redirects are sent only in response to data packets,
2227          * so that this nexthop apparently is reachable. --ANK
2228          */
2229         dst_confirm(&rt->dst);
2230
2231         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2232         if (!neigh)
2233                 return;
2234
2235         /*
2236          *      We have finally decided to accept it.
2237          */
2238
2239         ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
2240                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2241                      NEIGH_UPDATE_F_OVERRIDE|
2242                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2243                                      NEIGH_UPDATE_F_ISROUTER)),
2244                      NDISC_REDIRECT, &ndopts);
2245
2246         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2247         if (!nrt)
2248                 goto out;
2249
2250         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2251         if (on_link)
2252                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2253
2254         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2255
2256         if (ip6_ins_rt(nrt))
2257                 goto out;
2258
2259         netevent.old = &rt->dst;
2260         netevent.new = &nrt->dst;
2261         netevent.daddr = &msg->dest;
2262         netevent.neigh = neigh;
2263         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2264
2265         if (rt->rt6i_flags & RTF_CACHE) {
2266                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2267                 ip6_del_rt(rt);
2268         }
2269
2270 out:
2271         neigh_release(neigh);
2272 }
2273
2274 /*
2275  *      Misc support functions
2276  */
2277
2278 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2279 {
2280         BUG_ON(from->dst.from);
2281
2282         rt->rt6i_flags &= ~RTF_EXPIRES;
2283         dst_hold(&from->dst);
2284         rt->dst.from = &from->dst;
2285         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2286 }
2287
2288 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2289 {
2290         rt->dst.input = ort->dst.input;
2291         rt->dst.output = ort->dst.output;
2292         rt->rt6i_dst = ort->rt6i_dst;
2293         rt->dst.error = ort->dst.error;
2294         rt->rt6i_idev = ort->rt6i_idev;
2295         if (rt->rt6i_idev)
2296                 in6_dev_hold(rt->rt6i_idev);
2297         rt->dst.lastuse = jiffies;
2298         rt->rt6i_gateway = ort->rt6i_gateway;
2299         rt->rt6i_flags = ort->rt6i_flags;
2300         rt6_set_from(rt, ort);
2301         rt->rt6i_metric = ort->rt6i_metric;
2302 #ifdef CONFIG_IPV6_SUBTREES
2303         rt->rt6i_src = ort->rt6i_src;
2304 #endif
2305         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2306         rt->rt6i_table = ort->rt6i_table;
2307         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2308 }
2309
2310 #ifdef CONFIG_IPV6_ROUTE_INFO
2311 static struct rt6_info *rt6_get_route_info(struct net *net,
2312                                            const struct in6_addr *prefix, int prefixlen,
2313                                            const struct in6_addr *gwaddr, int ifindex)
2314 {
2315         struct fib6_node *fn;
2316         struct rt6_info *rt = NULL;
2317         struct fib6_table *table;
2318
2319         table = fib6_get_table(net, RT6_TABLE_INFO);
2320         if (!table)
2321                 return NULL;
2322
2323         read_lock_bh(&table->tb6_lock);
2324         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2325         if (!fn)
2326                 goto out;
2327
2328         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2329                 if (rt->dst.dev->ifindex != ifindex)
2330                         continue;
2331                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2332                         continue;
2333                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2334                         continue;
2335                 dst_hold(&rt->dst);
2336                 break;
2337         }
2338 out:
2339         read_unlock_bh(&table->tb6_lock);
2340         return rt;
2341 }
2342
2343 static struct rt6_info *rt6_add_route_info(struct net *net,
2344                                            const struct in6_addr *prefix, int prefixlen,
2345                                            const struct in6_addr *gwaddr, int ifindex,
2346                                            unsigned int pref)
2347 {
2348         struct fib6_config cfg = {
2349                 .fc_metric      = IP6_RT_PRIO_USER,
2350                 .fc_ifindex     = ifindex,
2351                 .fc_dst_len     = prefixlen,
2352                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2353                                   RTF_UP | RTF_PREF(pref),
2354                 .fc_nlinfo.portid = 0,
2355                 .fc_nlinfo.nlh = NULL,
2356                 .fc_nlinfo.nl_net = net,
2357         };
2358
2359         cfg.fc_table = l3mdev_fib_table_by_index(net, ifindex) ? : RT6_TABLE_INFO;
2360         cfg.fc_dst = *prefix;
2361         cfg.fc_gateway = *gwaddr;
2362
2363         /* We should treat it as a default route if prefix length is 0. */
2364         if (!prefixlen)
2365                 cfg.fc_flags |= RTF_DEFAULT;
2366
2367         ip6_route_add(&cfg);
2368
2369         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2370 }
2371 #endif
2372
2373 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2374 {
2375         struct rt6_info *rt;
2376         struct fib6_table *table;
2377
2378         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2379         if (!table)
2380                 return NULL;
2381
2382         read_lock_bh(&table->tb6_lock);
2383         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2384                 if (dev == rt->dst.dev &&
2385                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2386                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2387                         break;
2388         }
2389         if (rt)
2390                 dst_hold(&rt->dst);
2391         read_unlock_bh(&table->tb6_lock);
2392         return rt;
2393 }
2394
2395 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2396                                      struct net_device *dev,
2397                                      unsigned int pref)
2398 {
2399         struct fib6_config cfg = {
2400                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2401                 .fc_metric      = IP6_RT_PRIO_USER,
2402                 .fc_ifindex     = dev->ifindex,
2403                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2404                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2405                 .fc_nlinfo.portid = 0,
2406                 .fc_nlinfo.nlh = NULL,
2407                 .fc_nlinfo.nl_net = dev_net(dev),
2408         };
2409
2410         cfg.fc_gateway = *gwaddr;
2411
2412         ip6_route_add(&cfg);
2413
2414         return rt6_get_dflt_router(gwaddr, dev);
2415 }
2416
2417 void rt6_purge_dflt_routers(struct net *net)
2418 {
2419         struct rt6_info *rt;
2420         struct fib6_table *table;
2421
2422         /* NOTE: Keep consistent with rt6_get_dflt_router */
2423         table = fib6_get_table(net, RT6_TABLE_DFLT);
2424         if (!table)
2425                 return;
2426
2427 restart:
2428         read_lock_bh(&table->tb6_lock);
2429         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2430                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2431                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2432                         dst_hold(&rt->dst);
2433                         read_unlock_bh(&table->tb6_lock);
2434                         ip6_del_rt(rt);
2435                         goto restart;
2436                 }
2437         }
2438         read_unlock_bh(&table->tb6_lock);
2439 }
2440
2441 static void rtmsg_to_fib6_config(struct net *net,
2442                                  struct in6_rtmsg *rtmsg,
2443                                  struct fib6_config *cfg)
2444 {
2445         memset(cfg, 0, sizeof(*cfg));
2446
2447         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2448                          : RT6_TABLE_MAIN;
2449         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2450         cfg->fc_metric = rtmsg->rtmsg_metric;
2451         cfg->fc_expires = rtmsg->rtmsg_info;
2452         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2453         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2454         cfg->fc_flags = rtmsg->rtmsg_flags;
2455
2456         cfg->fc_nlinfo.nl_net = net;
2457
2458         cfg->fc_dst = rtmsg->rtmsg_dst;
2459         cfg->fc_src = rtmsg->rtmsg_src;
2460         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2461 }
2462
2463 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2464 {
2465         struct fib6_config cfg;
2466         struct in6_rtmsg rtmsg;
2467         int err;
2468
2469         switch (cmd) {
2470         case SIOCADDRT:         /* Add a route */
2471         case SIOCDELRT:         /* Delete a route */
2472                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2473                         return -EPERM;
2474                 err = copy_from_user(&rtmsg, arg,
2475                                      sizeof(struct in6_rtmsg));
2476                 if (err)
2477                         return -EFAULT;
2478
2479                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2480
2481                 rtnl_lock();
2482                 switch (cmd) {
2483                 case SIOCADDRT:
2484                         err = ip6_route_add(&cfg);
2485                         break;
2486                 case SIOCDELRT:
2487                         err = ip6_route_del(&cfg);
2488                         break;
2489                 default:
2490                         err = -EINVAL;
2491                 }
2492                 rtnl_unlock();
2493
2494                 return err;
2495         }
2496
2497         return -EINVAL;
2498 }
2499
2500 /*
2501  *      Drop the packet on the floor
2502  */
2503
2504 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2505 {
2506         int type;
2507         struct dst_entry *dst = skb_dst(skb);
2508         switch (ipstats_mib_noroutes) {
2509         case IPSTATS_MIB_INNOROUTES:
2510                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2511                 if (type == IPV6_ADDR_ANY) {
2512                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2513                                       IPSTATS_MIB_INADDRERRORS);
2514                         break;
2515                 }
2516                 /* FALLTHROUGH */
2517         case IPSTATS_MIB_OUTNOROUTES:
2518                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2519                               ipstats_mib_noroutes);
2520                 break;
2521         }
2522         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2523         kfree_skb(skb);
2524         return 0;
2525 }
2526
2527 static int ip6_pkt_discard(struct sk_buff *skb)
2528 {
2529         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2530 }
2531
2532 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2533 {
2534         skb->dev = skb_dst(skb)->dev;
2535         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2536 }
2537
2538 static int ip6_pkt_prohibit(struct sk_buff *skb)
2539 {
2540         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2541 }
2542
2543 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2544 {
2545         skb->dev = skb_dst(skb)->dev;
2546         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2547 }
2548
2549 /*
2550  *      Allocate a dst for local (unicast / anycast) address.
2551  */
2552
2553 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2554                                     const struct in6_addr *addr,
2555                                     bool anycast)
2556 {
2557         u32 tb_id;
2558         struct net *net = dev_net(idev->dev);
2559         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2560                                             DST_NOCOUNT);
2561         if (!rt)
2562                 return ERR_PTR(-ENOMEM);
2563
2564         in6_dev_hold(idev);
2565
2566         rt->dst.flags |= DST_HOST;
2567         rt->dst.input = ip6_input;
2568         rt->dst.output = ip6_output;
2569         rt->rt6i_idev = idev;
2570
2571         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2572         if (anycast)
2573                 rt->rt6i_flags |= RTF_ANYCAST;
2574         else
2575                 rt->rt6i_flags |= RTF_LOCAL;
2576
2577         rt->rt6i_gateway  = *addr;
2578         rt->rt6i_dst.addr = *addr;
2579         rt->rt6i_dst.plen = 128;
2580         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2581         rt->rt6i_table = fib6_get_table(net, tb_id);
2582         rt->dst.flags |= DST_NOCACHE;
2583
2584         atomic_set(&rt->dst.__refcnt, 1);
2585
2586         return rt;
2587 }
2588
2589 /* remove deleted ip from prefsrc entries */
2590 struct arg_dev_net_ip {
2591         struct net_device *dev;
2592         struct net *net;
2593         struct in6_addr *addr;
2594 };
2595
2596 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2597 {
2598         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2599         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2600         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2601
2602         if (((void *)rt->dst.dev == dev || !dev) &&
2603             rt != net->ipv6.ip6_null_entry &&
2604             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2605                 /* remove prefsrc entry */
2606                 rt->rt6i_prefsrc.plen = 0;
2607         }
2608         return 0;
2609 }
2610
2611 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2612 {
2613         struct net *net = dev_net(ifp->idev->dev);
2614         struct arg_dev_net_ip adni = {
2615                 .dev = ifp->idev->dev,
2616                 .net = net,
2617                 .addr = &ifp->addr,
2618         };
2619         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2620 }
2621
2622 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2623 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2624
2625 /* Remove routers and update dst entries when gateway turn into host. */
2626 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2627 {
2628         struct in6_addr *gateway = (struct in6_addr *)arg;
2629
2630         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2631              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2632              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2633                 return -1;
2634         }
2635         return 0;
2636 }
2637
2638 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2639 {
2640         fib6_clean_all(net, fib6_clean_tohost, gateway);
2641 }
2642
2643 struct arg_dev_net {
2644         struct net_device *dev;
2645         struct net *net;
2646 };
2647
2648 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2649 {
2650         const struct arg_dev_net *adn = arg;
2651         const struct net_device *dev = adn->dev;
2652
2653         if ((rt->dst.dev == dev || !dev) &&
2654             rt != adn->net->ipv6.ip6_null_entry)
2655                 return -1;
2656
2657         return 0;
2658 }
2659
2660 void rt6_ifdown(struct net *net, struct net_device *dev)
2661 {
2662         struct arg_dev_net adn = {
2663                 .dev = dev,
2664                 .net = net,
2665         };
2666
2667         fib6_clean_all(net, fib6_ifdown, &adn);
2668         icmp6_clean_all(fib6_ifdown, &adn);
2669         if (dev)
2670                 rt6_uncached_list_flush_dev(net, dev);
2671 }
2672
2673 struct rt6_mtu_change_arg {
2674         struct net_device *dev;
2675         unsigned int mtu;
2676 };
2677
2678 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2679 {
2680         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2681         struct inet6_dev *idev;
2682
2683         /* In IPv6 pmtu discovery is not optional,
2684            so that RTAX_MTU lock cannot disable it.
2685            We still use this lock to block changes
2686            caused by addrconf/ndisc.
2687         */
2688
2689         idev = __in6_dev_get(arg->dev);
2690         if (!idev)
2691                 return 0;
2692
2693         /* For administrative MTU increase, there is no way to discover
2694            IPv6 PMTU increase, so PMTU increase should be updated here.
2695            Since RFC 1981 doesn't include administrative MTU increase
2696            update PMTU increase is a MUST. (i.e. jumbo frame)
2697          */
2698         /*
2699            If new MTU is less than route PMTU, this new MTU will be the
2700            lowest MTU in the path, update the route PMTU to reflect PMTU
2701            decreases; if new MTU is greater than route PMTU, and the
2702            old MTU is the lowest MTU in the path, update the route PMTU
2703            to reflect the increase. In this case if the other nodes' MTU
2704            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2705            PMTU discouvery.
2706          */
2707         if (rt->dst.dev == arg->dev &&
2708             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2709                 if (rt->rt6i_flags & RTF_CACHE) {
2710                         /* For RTF_CACHE with rt6i_pmtu == 0
2711                          * (i.e. a redirected route),
2712                          * the metrics of its rt->dst.from has already
2713                          * been updated.
2714                          */
2715                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2716                                 rt->rt6i_pmtu = arg->mtu;
2717                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2718                            (dst_mtu(&rt->dst) < arg->mtu &&
2719                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2720                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2721                 }
2722         }
2723         return 0;
2724 }
2725
2726 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2727 {
2728         struct rt6_mtu_change_arg arg = {
2729                 .dev = dev,
2730                 .mtu = mtu,
2731         };
2732
2733         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2734 }
2735
2736 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2737         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2738         [RTA_OIF]               = { .type = NLA_U32 },
2739         [RTA_IIF]               = { .type = NLA_U32 },
2740         [RTA_PRIORITY]          = { .type = NLA_U32 },
2741         [RTA_METRICS]           = { .type = NLA_NESTED },
2742         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2743         [RTA_PREF]              = { .type = NLA_U8 },
2744         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2745         [RTA_ENCAP]             = { .type = NLA_NESTED },
2746         [RTA_EXPIRES]           = { .type = NLA_U32 },
2747 };
2748
2749 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2750                               struct fib6_config *cfg)
2751 {
2752         struct rtmsg *rtm;
2753         struct nlattr *tb[RTA_MAX+1];
2754         unsigned int pref;
2755         int err;
2756
2757         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2758         if (err < 0)
2759                 goto errout;
2760
2761         err = -EINVAL;
2762         rtm = nlmsg_data(nlh);
2763         memset(cfg, 0, sizeof(*cfg));
2764
2765         cfg->fc_table = rtm->rtm_table;
2766         cfg->fc_dst_len = rtm->rtm_dst_len;
2767         cfg->fc_src_len = rtm->rtm_src_len;
2768         cfg->fc_flags = RTF_UP;
2769         cfg->fc_protocol = rtm->rtm_protocol;
2770         cfg->fc_type = rtm->rtm_type;
2771
2772         if (rtm->rtm_type == RTN_UNREACHABLE ||
2773             rtm->rtm_type == RTN_BLACKHOLE ||
2774             rtm->rtm_type == RTN_PROHIBIT ||
2775             rtm->rtm_type == RTN_THROW)
2776                 cfg->fc_flags |= RTF_REJECT;
2777
2778         if (rtm->rtm_type == RTN_LOCAL)
2779                 cfg->fc_flags |= RTF_LOCAL;
2780
2781         if (rtm->rtm_flags & RTM_F_CLONED)
2782                 cfg->fc_flags |= RTF_CACHE;
2783
2784         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2785         cfg->fc_nlinfo.nlh = nlh;
2786         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2787
2788         if (tb[RTA_GATEWAY]) {
2789                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2790                 cfg->fc_flags |= RTF_GATEWAY;
2791         }
2792
2793         if (tb[RTA_DST]) {
2794                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2795
2796                 if (nla_len(tb[RTA_DST]) < plen)
2797                         goto errout;
2798
2799                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2800         }
2801
2802         if (tb[RTA_SRC]) {
2803                 int plen = (rtm->rtm_src_len + 7) >> 3;
2804
2805                 if (nla_len(tb[RTA_SRC]) < plen)
2806                         goto errout;
2807
2808                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2809         }
2810
2811         if (tb[RTA_PREFSRC])
2812                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2813
2814         if (tb[RTA_OIF])
2815                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2816
2817         if (tb[RTA_PRIORITY])
2818                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2819
2820         if (tb[RTA_METRICS]) {
2821                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2822                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2823         }
2824
2825         if (tb[RTA_TABLE])
2826                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2827
2828         if (tb[RTA_MULTIPATH]) {
2829                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2830                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2831         }
2832
2833         if (tb[RTA_PREF]) {
2834                 pref = nla_get_u8(tb[RTA_PREF]);
2835                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2836                     pref != ICMPV6_ROUTER_PREF_HIGH)
2837                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2838                 cfg->fc_flags |= RTF_PREF(pref);
2839         }
2840
2841         if (tb[RTA_ENCAP])
2842                 cfg->fc_encap = tb[RTA_ENCAP];
2843
2844         if (tb[RTA_ENCAP_TYPE])
2845                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2846
2847         if (tb[RTA_EXPIRES]) {
2848                 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
2849
2850                 if (addrconf_finite_timeout(timeout)) {
2851                         cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
2852                         cfg->fc_flags |= RTF_EXPIRES;
2853                 }
2854         }
2855
2856         err = 0;
2857 errout:
2858         return err;
2859 }
2860
2861 struct rt6_nh {
2862         struct rt6_info *rt6_info;
2863         struct fib6_config r_cfg;
2864         struct mx6_config mxc;
2865         struct list_head next;
2866 };
2867
2868 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2869 {
2870         struct rt6_nh *nh;
2871
2872         list_for_each_entry(nh, rt6_nh_list, next) {
2873                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2874                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2875                         nh->r_cfg.fc_ifindex);
2876         }
2877 }
2878
2879 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2880                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2881 {
2882         struct rt6_nh *nh;
2883         struct rt6_info *rtnh;
2884         int err = -EEXIST;
2885
2886         list_for_each_entry(nh, rt6_nh_list, next) {
2887                 /* check if rt6_info already exists */
2888                 rtnh = nh->rt6_info;
2889
2890                 if (rtnh->dst.dev == rt->dst.dev &&
2891                     rtnh->rt6i_idev == rt->rt6i_idev &&
2892                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2893                                     &rt->rt6i_gateway))
2894                         return err;
2895         }
2896
2897         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2898         if (!nh)
2899                 return -ENOMEM;
2900         nh->rt6_info = rt;
2901         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2902         if (err) {
2903                 kfree(nh);
2904                 return err;
2905         }
2906         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2907         list_add_tail(&nh->next, rt6_nh_list);
2908
2909         return 0;
2910 }
2911
2912 static int ip6_route_multipath_add(struct fib6_config *cfg)
2913 {
2914         struct fib6_config r_cfg;
2915         struct rtnexthop *rtnh;
2916         struct rt6_info *rt;
2917         struct rt6_nh *err_nh;
2918         struct rt6_nh *nh, *nh_safe;
2919         int remaining;
2920         int attrlen;
2921         int err = 1;
2922         int nhn = 0;
2923         int replace = (cfg->fc_nlinfo.nlh &&
2924                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2925         LIST_HEAD(rt6_nh_list);
2926
2927         remaining = cfg->fc_mp_len;
2928         rtnh = (struct rtnexthop *)cfg->fc_mp;
2929
2930         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2931          * rt6_info structs per nexthop
2932          */
2933         while (rtnh_ok(rtnh, remaining)) {
2934                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2935                 if (rtnh->rtnh_ifindex)
2936                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2937
2938                 attrlen = rtnh_attrlen(rtnh);
2939                 if (attrlen > 0) {
2940                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2941
2942                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2943                         if (nla) {
2944                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2945                                 r_cfg.fc_flags |= RTF_GATEWAY;
2946                         }
2947                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2948                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2949                         if (nla)
2950                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2951                 }
2952
2953                 rt = ip6_route_info_create(&r_cfg);
2954                 if (IS_ERR(rt)) {
2955                         err = PTR_ERR(rt);
2956                         rt = NULL;
2957                         goto cleanup;
2958                 }
2959
2960                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2961                 if (err) {
2962                         dst_free(&rt->dst);
2963                         goto cleanup;
2964                 }
2965
2966                 rtnh = rtnh_next(rtnh, &remaining);
2967         }
2968
2969         err_nh = NULL;
2970         list_for_each_entry(nh, &rt6_nh_list, next) {
2971                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2972                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2973                 nh->rt6_info = NULL;
2974                 if (err) {
2975                         if (replace && nhn)
2976                                 ip6_print_replace_route_err(&rt6_nh_list);
2977                         err_nh = nh;
2978                         goto add_errout;
2979                 }
2980
2981                 /* Because each route is added like a single route we remove
2982                  * these flags after the first nexthop: if there is a collision,
2983                  * we have already failed to add the first nexthop:
2984                  * fib6_add_rt2node() has rejected it; when replacing, old
2985                  * nexthops have been replaced by first new, the rest should
2986                  * be added to it.
2987                  */
2988                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2989                                                      NLM_F_REPLACE);
2990                 nhn++;
2991         }
2992
2993         goto cleanup;
2994
2995 add_errout:
2996         /* Delete routes that were already added */
2997         list_for_each_entry(nh, &rt6_nh_list, next) {
2998                 if (err_nh == nh)
2999                         break;
3000                 ip6_route_del(&nh->r_cfg);
3001         }
3002
3003 cleanup:
3004         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
3005                 if (nh->rt6_info)
3006                         dst_free(&nh->rt6_info->dst);
3007                 kfree(nh->mxc.mx);
3008                 list_del(&nh->next);
3009                 kfree(nh);
3010         }
3011
3012         return err;
3013 }
3014
3015 static int ip6_route_multipath_del(struct fib6_config *cfg)
3016 {
3017         struct fib6_config r_cfg;
3018         struct rtnexthop *rtnh;
3019         int remaining;
3020         int attrlen;
3021         int err = 1, last_err = 0;
3022
3023         remaining = cfg->fc_mp_len;
3024         rtnh = (struct rtnexthop *)cfg->fc_mp;
3025
3026         /* Parse a Multipath Entry */
3027         while (rtnh_ok(rtnh, remaining)) {
3028                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3029                 if (rtnh->rtnh_ifindex)
3030                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3031
3032                 attrlen = rtnh_attrlen(rtnh);
3033                 if (attrlen > 0) {
3034                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3035
3036                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3037                         if (nla) {
3038                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3039                                 r_cfg.fc_flags |= RTF_GATEWAY;
3040                         }
3041                 }
3042                 err = ip6_route_del(&r_cfg);
3043                 if (err)
3044                         last_err = err;
3045
3046                 rtnh = rtnh_next(rtnh, &remaining);
3047         }
3048
3049         return last_err;
3050 }
3051
3052 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3053 {
3054         struct fib6_config cfg;
3055         int err;
3056
3057         err = rtm_to_fib6_config(skb, nlh, &cfg);
3058         if (err < 0)
3059                 return err;
3060
3061         if (cfg.fc_mp)
3062                 return ip6_route_multipath_del(&cfg);
3063         else
3064                 return ip6_route_del(&cfg);
3065 }
3066
3067 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3068 {
3069         struct fib6_config cfg;
3070         int err;
3071
3072         err = rtm_to_fib6_config(skb, nlh, &cfg);
3073         if (err < 0)
3074                 return err;
3075
3076         if (cfg.fc_mp)
3077                 return ip6_route_multipath_add(&cfg);
3078         else
3079                 return ip6_route_add(&cfg);
3080 }
3081
3082 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3083 {
3084         return NLMSG_ALIGN(sizeof(struct rtmsg))
3085                + nla_total_size(16) /* RTA_SRC */
3086                + nla_total_size(16) /* RTA_DST */
3087                + nla_total_size(16) /* RTA_GATEWAY */
3088                + nla_total_size(16) /* RTA_PREFSRC */
3089                + nla_total_size(4) /* RTA_TABLE */
3090                + nla_total_size(4) /* RTA_IIF */
3091                + nla_total_size(4) /* RTA_OIF */
3092                + nla_total_size(4) /* RTA_PRIORITY */
3093                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3094                + nla_total_size(sizeof(struct rta_cacheinfo))
3095                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3096                + nla_total_size(1) /* RTA_PREF */
3097                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3098 }
3099
3100 static int rt6_fill_node(struct net *net,
3101                          struct sk_buff *skb, struct rt6_info *rt,
3102                          struct in6_addr *dst, struct in6_addr *src,
3103                          int iif, int type, u32 portid, u32 seq,
3104                          int prefix, int nowait, unsigned int flags)
3105 {
3106         u32 metrics[RTAX_MAX];
3107         struct rtmsg *rtm;
3108         struct nlmsghdr *nlh;
3109         long expires;
3110         u32 table;
3111
3112         if (prefix) {   /* user wants prefix routes only */
3113                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3114                         /* success since this is not a prefix route */
3115                         return 1;
3116                 }
3117         }
3118
3119         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3120         if (!nlh)
3121                 return -EMSGSIZE;
3122
3123         rtm = nlmsg_data(nlh);
3124         rtm->rtm_family = AF_INET6;
3125         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3126         rtm->rtm_src_len = rt->rt6i_src.plen;
3127         rtm->rtm_tos = 0;
3128         if (rt->rt6i_table)
3129                 table = rt->rt6i_table->tb6_id;
3130         else
3131                 table = RT6_TABLE_UNSPEC;
3132         rtm->rtm_table = table;
3133         if (nla_put_u32(skb, RTA_TABLE, table))
3134                 goto nla_put_failure;
3135         if (rt->rt6i_flags & RTF_REJECT) {
3136                 switch (rt->dst.error) {
3137                 case -EINVAL:
3138                         rtm->rtm_type = RTN_BLACKHOLE;
3139                         break;
3140                 case -EACCES:
3141                         rtm->rtm_type = RTN_PROHIBIT;
3142                         break;
3143                 case -EAGAIN:
3144                         rtm->rtm_type = RTN_THROW;
3145                         break;
3146                 default:
3147                         rtm->rtm_type = RTN_UNREACHABLE;
3148                         break;
3149                 }
3150         }
3151         else if (rt->rt6i_flags & RTF_LOCAL)
3152                 rtm->rtm_type = RTN_LOCAL;
3153         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3154                 rtm->rtm_type = RTN_LOCAL;
3155         else
3156                 rtm->rtm_type = RTN_UNICAST;
3157         rtm->rtm_flags = 0;
3158         if (!netif_carrier_ok(rt->dst.dev)) {
3159                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3160                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3161                         rtm->rtm_flags |= RTNH_F_DEAD;
3162         }
3163         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3164         rtm->rtm_protocol = rt->rt6i_protocol;
3165         if (rt->rt6i_flags & RTF_DYNAMIC)
3166                 rtm->rtm_protocol = RTPROT_REDIRECT;
3167         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3168                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3169                         rtm->rtm_protocol = RTPROT_RA;
3170                 else
3171                         rtm->rtm_protocol = RTPROT_KERNEL;
3172         }
3173
3174         if (rt->rt6i_flags & RTF_CACHE)
3175                 rtm->rtm_flags |= RTM_F_CLONED;
3176
3177         if (dst) {
3178                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3179                         goto nla_put_failure;
3180                 rtm->rtm_dst_len = 128;
3181         } else if (rtm->rtm_dst_len)
3182                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3183                         goto nla_put_failure;
3184 #ifdef CONFIG_IPV6_SUBTREES
3185         if (src) {
3186                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3187                         goto nla_put_failure;
3188                 rtm->rtm_src_len = 128;
3189         } else if (rtm->rtm_src_len &&
3190                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3191                 goto nla_put_failure;
3192 #endif
3193         if (iif) {
3194 #ifdef CONFIG_IPV6_MROUTE
3195                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3196                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3197                         if (err <= 0) {
3198                                 if (!nowait) {
3199                                         if (err == 0)
3200                                                 return 0;
3201                                         goto nla_put_failure;
3202                                 } else {
3203                                         if (err == -EMSGSIZE)
3204                                                 goto nla_put_failure;
3205                                 }
3206                         }
3207                 } else
3208 #endif
3209                         if (nla_put_u32(skb, RTA_IIF, iif))
3210                                 goto nla_put_failure;
3211         } else if (dst) {
3212                 struct in6_addr saddr_buf;
3213                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3214                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3215                         goto nla_put_failure;
3216         }
3217
3218         if (rt->rt6i_prefsrc.plen) {
3219                 struct in6_addr saddr_buf;
3220                 saddr_buf = rt->rt6i_prefsrc.addr;
3221                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3222                         goto nla_put_failure;
3223         }
3224
3225         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3226         if (rt->rt6i_pmtu)
3227                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3228         if (rtnetlink_put_metrics(skb, metrics) < 0)
3229                 goto nla_put_failure;
3230
3231         if (rt->rt6i_flags & RTF_GATEWAY) {
3232                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3233                         goto nla_put_failure;
3234         }
3235
3236         if (rt->dst.dev &&
3237             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3238                 goto nla_put_failure;
3239         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3240                 goto nla_put_failure;
3241
3242         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3243
3244         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3245                 goto nla_put_failure;
3246
3247         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3248                 goto nla_put_failure;
3249
3250         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3251
3252         nlmsg_end(skb, nlh);
3253         return 0;
3254
3255 nla_put_failure:
3256         nlmsg_cancel(skb, nlh);
3257         return -EMSGSIZE;
3258 }
3259
3260 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3261 {
3262         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3263         int prefix;
3264
3265         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3266                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3267                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3268         } else
3269                 prefix = 0;
3270
3271         return rt6_fill_node(arg->net,
3272                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3273                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3274                      prefix, 0, NLM_F_MULTI);
3275 }
3276
3277 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3278 {
3279         struct net *net = sock_net(in_skb->sk);
3280         struct nlattr *tb[RTA_MAX+1];
3281         struct rt6_info *rt;
3282         struct sk_buff *skb;
3283         struct rtmsg *rtm;
3284         struct flowi6 fl6;
3285         int err, iif = 0, oif = 0;
3286
3287         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3288         if (err < 0)
3289                 goto errout;
3290
3291         err = -EINVAL;
3292         memset(&fl6, 0, sizeof(fl6));
3293         rtm = nlmsg_data(nlh);
3294         fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0);
3295
3296         if (tb[RTA_SRC]) {
3297                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3298                         goto errout;
3299
3300                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3301         }
3302
3303         if (tb[RTA_DST]) {
3304                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3305                         goto errout;
3306
3307                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3308         }
3309
3310         if (tb[RTA_IIF])
3311                 iif = nla_get_u32(tb[RTA_IIF]);
3312
3313         if (tb[RTA_OIF])
3314                 oif = nla_get_u32(tb[RTA_OIF]);
3315
3316         if (tb[RTA_MARK])
3317                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3318
3319         if (iif) {
3320                 struct net_device *dev;
3321                 int flags = 0;
3322
3323                 dev = __dev_get_by_index(net, iif);
3324                 if (!dev) {
3325                         err = -ENODEV;
3326                         goto errout;
3327                 }
3328
3329                 fl6.flowi6_iif = iif;
3330
3331                 if (!ipv6_addr_any(&fl6.saddr))
3332                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3333
3334                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3335                                                                flags);
3336         } else {
3337                 fl6.flowi6_oif = oif;
3338
3339                 if (netif_index_is_l3_master(net, oif)) {
3340                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3341                                            FLOWI_FLAG_SKIP_NH_OIF;
3342                 }
3343
3344                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3345         }
3346
3347         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3348         if (!skb) {
3349                 ip6_rt_put(rt);
3350                 err = -ENOBUFS;
3351                 goto errout;
3352         }
3353
3354         /* Reserve room for dummy headers, this skb can pass
3355            through good chunk of routing engine.
3356          */
3357         skb_reset_mac_header(skb);
3358         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3359
3360         skb_dst_set(skb, &rt->dst);
3361
3362         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3363                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3364                             nlh->nlmsg_seq, 0, 0, 0);
3365         if (err < 0) {
3366                 kfree_skb(skb);
3367                 goto errout;
3368         }
3369
3370         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3371 errout:
3372         return err;
3373 }
3374
3375 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3376                      unsigned int nlm_flags)
3377 {
3378         struct sk_buff *skb;
3379         struct net *net = info->nl_net;
3380         u32 seq;
3381         int err;
3382
3383         err = -ENOBUFS;
3384         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3385
3386         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3387         if (!skb)
3388                 goto errout;
3389
3390         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3391                                 event, info->portid, seq, 0, 0, nlm_flags);
3392         if (err < 0) {
3393                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3394                 WARN_ON(err == -EMSGSIZE);
3395                 kfree_skb(skb);
3396                 goto errout;
3397         }
3398         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3399                     info->nlh, gfp_any());
3400         return;
3401 errout:
3402         if (err < 0)
3403                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3404 }
3405
3406 static int ip6_route_dev_notify(struct notifier_block *this,
3407                                 unsigned long event, void *ptr)
3408 {
3409         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3410         struct net *net = dev_net(dev);
3411
3412         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3413                 net->ipv6.ip6_null_entry->dst.dev = dev;
3414                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3415 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3416                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3417                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3418                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3419                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3420 #endif
3421         }
3422
3423         return NOTIFY_OK;
3424 }
3425
3426 /*
3427  *      /proc
3428  */
3429
3430 #ifdef CONFIG_PROC_FS
3431
3432 static const struct file_operations ipv6_route_proc_fops = {
3433         .owner          = THIS_MODULE,
3434         .open           = ipv6_route_open,
3435         .read           = seq_read,
3436         .llseek         = seq_lseek,
3437         .release        = seq_release_net,
3438 };
3439
3440 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3441 {
3442         struct net *net = (struct net *)seq->private;
3443         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3444                    net->ipv6.rt6_stats->fib_nodes,
3445                    net->ipv6.rt6_stats->fib_route_nodes,
3446                    net->ipv6.rt6_stats->fib_rt_alloc,
3447                    net->ipv6.rt6_stats->fib_rt_entries,
3448                    net->ipv6.rt6_stats->fib_rt_cache,
3449                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3450                    net->ipv6.rt6_stats->fib_discarded_routes);
3451
3452         return 0;
3453 }
3454
3455 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3456 {
3457         return single_open_net(inode, file, rt6_stats_seq_show);
3458 }
3459
3460 static const struct file_operations rt6_stats_seq_fops = {
3461         .owner   = THIS_MODULE,
3462         .open    = rt6_stats_seq_open,
3463         .read    = seq_read,
3464         .llseek  = seq_lseek,
3465         .release = single_release_net,
3466 };
3467 #endif  /* CONFIG_PROC_FS */
3468
3469 #ifdef CONFIG_SYSCTL
3470
3471 static
3472 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3473                               void __user *buffer, size_t *lenp, loff_t *ppos)
3474 {
3475         struct net *net;
3476         int delay;
3477         if (!write)
3478                 return -EINVAL;
3479
3480         net = (struct net *)ctl->extra1;
3481         delay = net->ipv6.sysctl.flush_delay;
3482         proc_dointvec(ctl, write, buffer, lenp, ppos);
3483         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3484         return 0;
3485 }
3486
3487 struct ctl_table ipv6_route_table_template[] = {
3488         {
3489                 .procname       =       "flush",
3490                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3491                 .maxlen         =       sizeof(int),
3492                 .mode           =       0200,
3493                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3494         },
3495         {
3496                 .procname       =       "gc_thresh",
3497                 .data           =       &ip6_dst_ops_template.gc_thresh,
3498                 .maxlen         =       sizeof(int),
3499                 .mode           =       0644,
3500                 .proc_handler   =       proc_dointvec,
3501         },
3502         {
3503                 .procname       =       "max_size",
3504                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3505                 .maxlen         =       sizeof(int),
3506                 .mode           =       0644,
3507                 .proc_handler   =       proc_dointvec,
3508         },
3509         {
3510                 .procname       =       "gc_min_interval",
3511                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3512                 .maxlen         =       sizeof(int),
3513                 .mode           =       0644,
3514                 .proc_handler   =       proc_dointvec_jiffies,
3515         },
3516         {
3517                 .procname       =       "gc_timeout",
3518                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3519                 .maxlen         =       sizeof(int),
3520                 .mode           =       0644,
3521                 .proc_handler   =       proc_dointvec_jiffies,
3522         },
3523         {
3524                 .procname       =       "gc_interval",
3525                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3526                 .maxlen         =       sizeof(int),
3527                 .mode           =       0644,
3528                 .proc_handler   =       proc_dointvec_jiffies,
3529         },
3530         {
3531                 .procname       =       "gc_elasticity",
3532                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3533                 .maxlen         =       sizeof(int),
3534                 .mode           =       0644,
3535                 .proc_handler   =       proc_dointvec,
3536         },
3537         {
3538                 .procname       =       "mtu_expires",
3539                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3540                 .maxlen         =       sizeof(int),
3541                 .mode           =       0644,
3542                 .proc_handler   =       proc_dointvec_jiffies,
3543         },
3544         {
3545                 .procname       =       "min_adv_mss",
3546                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3547                 .maxlen         =       sizeof(int),
3548                 .mode           =       0644,
3549                 .proc_handler   =       proc_dointvec,
3550         },
3551         {
3552                 .procname       =       "gc_min_interval_ms",
3553                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3554                 .maxlen         =       sizeof(int),
3555                 .mode           =       0644,
3556                 .proc_handler   =       proc_dointvec_ms_jiffies,
3557         },
3558         { }
3559 };
3560
3561 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3562 {
3563         struct ctl_table *table;
3564
3565         table = kmemdup(ipv6_route_table_template,
3566                         sizeof(ipv6_route_table_template),
3567                         GFP_KERNEL);
3568
3569         if (table) {
3570                 table[0].data = &net->ipv6.sysctl.flush_delay;
3571                 table[0].extra1 = net;
3572                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3573                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3574                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3575                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3576                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3577                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3578                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3579                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3580                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3581
3582                 /* Don't export sysctls to unprivileged users */
3583                 if (net->user_ns != &init_user_ns)
3584                         table[0].procname = NULL;
3585         }
3586
3587         return table;
3588 }
3589 #endif
3590
3591 static int __net_init ip6_route_net_init(struct net *net)
3592 {
3593         int ret = -ENOMEM;
3594
3595         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3596                sizeof(net->ipv6.ip6_dst_ops));
3597
3598         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3599                 goto out_ip6_dst_ops;
3600
3601         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3602                                            sizeof(*net->ipv6.ip6_null_entry),
3603                                            GFP_KERNEL);
3604         if (!net->ipv6.ip6_null_entry)
3605                 goto out_ip6_dst_entries;
3606         net->ipv6.ip6_null_entry->dst.path =
3607                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3608         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3609         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3610                          ip6_template_metrics, true);
3611
3612 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3613         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3614                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3615                                                GFP_KERNEL);
3616         if (!net->ipv6.ip6_prohibit_entry)
3617                 goto out_ip6_null_entry;
3618         net->ipv6.ip6_prohibit_entry->dst.path =
3619                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3620         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3621         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3622                          ip6_template_metrics, true);
3623
3624         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3625                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3626                                                GFP_KERNEL);
3627         if (!net->ipv6.ip6_blk_hole_entry)
3628                 goto out_ip6_prohibit_entry;
3629         net->ipv6.ip6_blk_hole_entry->dst.path =
3630                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3631         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3632         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3633                          ip6_template_metrics, true);
3634 #endif
3635
3636         net->ipv6.sysctl.flush_delay = 0;
3637         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3638         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3639         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3640         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3641         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3642         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3643         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3644
3645         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3646
3647         ret = 0;
3648 out:
3649         return ret;
3650
3651 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3652 out_ip6_prohibit_entry:
3653         kfree(net->ipv6.ip6_prohibit_entry);
3654 out_ip6_null_entry:
3655         kfree(net->ipv6.ip6_null_entry);
3656 #endif
3657 out_ip6_dst_entries:
3658         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3659 out_ip6_dst_ops:
3660         goto out;
3661 }
3662
3663 static void __net_exit ip6_route_net_exit(struct net *net)
3664 {
3665         kfree(net->ipv6.ip6_null_entry);
3666 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3667         kfree(net->ipv6.ip6_prohibit_entry);
3668         kfree(net->ipv6.ip6_blk_hole_entry);
3669 #endif
3670         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3671 }
3672
3673 static int __net_init ip6_route_net_init_late(struct net *net)
3674 {
3675 #ifdef CONFIG_PROC_FS
3676         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3677         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3678 #endif
3679         return 0;
3680 }
3681
3682 static void __net_exit ip6_route_net_exit_late(struct net *net)
3683 {
3684 #ifdef CONFIG_PROC_FS
3685         remove_proc_entry("ipv6_route", net->proc_net);
3686         remove_proc_entry("rt6_stats", net->proc_net);
3687 #endif
3688 }
3689
3690 static struct pernet_operations ip6_route_net_ops = {
3691         .init = ip6_route_net_init,
3692         .exit = ip6_route_net_exit,
3693 };
3694
3695 static int __net_init ipv6_inetpeer_init(struct net *net)
3696 {
3697         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3698
3699         if (!bp)
3700                 return -ENOMEM;
3701         inet_peer_base_init(bp);
3702         net->ipv6.peers = bp;
3703         return 0;
3704 }
3705
3706 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3707 {
3708         struct inet_peer_base *bp = net->ipv6.peers;
3709
3710         net->ipv6.peers = NULL;
3711         inetpeer_invalidate_tree(bp);
3712         kfree(bp);
3713 }
3714
3715 static struct pernet_operations ipv6_inetpeer_ops = {
3716         .init   =       ipv6_inetpeer_init,
3717         .exit   =       ipv6_inetpeer_exit,
3718 };
3719
3720 static struct pernet_operations ip6_route_net_late_ops = {
3721         .init = ip6_route_net_init_late,
3722         .exit = ip6_route_net_exit_late,
3723 };
3724
3725 static struct notifier_block ip6_route_dev_notifier = {
3726         .notifier_call = ip6_route_dev_notify,
3727         .priority = 0,
3728 };
3729
3730 int __init ip6_route_init(void)
3731 {
3732         int ret;
3733         int cpu;
3734
3735         ret = -ENOMEM;
3736         ip6_dst_ops_template.kmem_cachep =
3737                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3738                                   SLAB_HWCACHE_ALIGN, NULL);
3739         if (!ip6_dst_ops_template.kmem_cachep)
3740                 goto out;
3741
3742         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3743         if (ret)
3744                 goto out_kmem_cache;
3745
3746         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3747         if (ret)
3748                 goto out_dst_entries;
3749
3750         ret = register_pernet_subsys(&ip6_route_net_ops);
3751         if (ret)
3752                 goto out_register_inetpeer;
3753
3754         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3755
3756         /* Registering of the loopback is done before this portion of code,
3757          * the loopback reference in rt6_info will not be taken, do it
3758          * manually for init_net */
3759         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3760         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3761   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3762         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3763         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3764         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3765         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3766   #endif
3767         ret = fib6_init();
3768         if (ret)
3769                 goto out_register_subsys;
3770
3771         ret = xfrm6_init();
3772         if (ret)
3773                 goto out_fib6_init;
3774
3775         ret = fib6_rules_init();
3776         if (ret)
3777                 goto xfrm6_init;
3778
3779         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3780         if (ret)
3781                 goto fib6_rules_init;
3782
3783         ret = -ENOBUFS;
3784         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3785             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3786             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3787                 goto out_register_late_subsys;
3788
3789         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3790         if (ret)
3791                 goto out_register_late_subsys;
3792
3793         for_each_possible_cpu(cpu) {
3794                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3795
3796                 INIT_LIST_HEAD(&ul->head);
3797                 spin_lock_init(&ul->lock);
3798         }
3799
3800 out:
3801         return ret;
3802
3803 out_register_late_subsys:
3804         unregister_pernet_subsys(&ip6_route_net_late_ops);
3805 fib6_rules_init:
3806         fib6_rules_cleanup();
3807 xfrm6_init:
3808         xfrm6_fini();
3809 out_fib6_init:
3810         fib6_gc_cleanup();
3811 out_register_subsys:
3812         unregister_pernet_subsys(&ip6_route_net_ops);
3813 out_register_inetpeer:
3814         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3815 out_dst_entries:
3816         dst_entries_destroy(&ip6_dst_blackhole_ops);
3817 out_kmem_cache:
3818         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3819         goto out;
3820 }
3821
3822 void ip6_route_cleanup(void)
3823 {
3824         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3825         unregister_pernet_subsys(&ip6_route_net_late_ops);
3826         fib6_rules_cleanup();
3827         xfrm6_fini();
3828         fib6_gc_cleanup();
3829         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3830         unregister_pernet_subsys(&ip6_route_net_ops);
3831         dst_entries_destroy(&ip6_dst_blackhole_ops);
3832         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3833 }