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
  66 #include <asm/uaccess.h>
  67
  68 #ifdef CONFIG_SYSCTL
  69 #include <linux/sysctl.h>
  70 #endif
  71
  72 enum rt6_nud_state {
  73         RT6_NUD_FAIL_HARD = -3,
  74         RT6_NUD_FAIL_PROBE = -2,
  75         RT6_NUD_FAIL_DO_RR = -1,
  76         RT6_NUD_SUCCEED = 1
  77 };
  78
  79 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  80 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  81 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  82 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  83 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  84 static void             ip6_dst_destroy(struct dst_entry *);
  85 static void             ip6_dst_ifdown(struct dst_entry *,
  86                                        struct net_device *dev, int how);
  87 static int               ip6_dst_gc(struct dst_ops *ops);
  88
  89 static int              ip6_pkt_discard(struct sk_buff *skb);
  90 static int              ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  91 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  92 static int              ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  93 static void             ip6_link_failure(struct sk_buff *skb);
  94 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  95                                            struct sk_buff *skb, u32 mtu);
  96 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  97                                         struct sk_buff *skb);
  98 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
  99 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
 100
 101 #ifdef CONFIG_IPV6_ROUTE_INFO
 102 static struct rt6_info *rt6_add_route_info(struct net *net,
 103                                            const struct in6_addr *prefix, int prefixlen,
 104                                            const struct in6_addr *gwaddr, int ifindex,
 105                                            unsigned int pref);
 106 static struct rt6_info *rt6_get_route_info(struct net *net,
 107                                            const struct in6_addr *prefix, int prefixlen,
 108                                            const struct in6_addr *gwaddr, int ifindex);
 109 #endif
 110
 111 struct uncached_list {
 112         spinlock_t              lock;
 113         struct list_head        head;
 114 };
 115
 116 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 117
 118 static void rt6_uncached_list_add(struct rt6_info *rt)
 119 {
 120         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 121
 122         rt->dst.flags |= DST_NOCACHE;
 123         rt->rt6i_uncached_list = ul;
 124
 125         spin_lock_bh(&ul->lock);
 126         list_add_tail(&rt->rt6i_uncached, &ul->head);
 127         spin_unlock_bh(&ul->lock);
 128 }
 129
 130 static void rt6_uncached_list_del(struct rt6_info *rt)
 131 {
 132         if (!list_empty(&rt->rt6i_uncached)) {
 133                 struct uncached_list *ul = rt->rt6i_uncached_list;
 134
 135                 spin_lock_bh(&ul->lock);
 136                 list_del(&rt->rt6i_uncached);
 137                 spin_unlock_bh(&ul->lock);
 138         }
 139 }
 140
 141 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 142 {
 143         struct net_device *loopback_dev = net->loopback_dev;
 144         int cpu;
 145
 146         for_each_possible_cpu(cpu) {
 147                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 148                 struct rt6_info *rt;
 149
 150                 spin_lock_bh(&ul->lock);
 151                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 152                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 153                         struct net_device *rt_dev = rt->dst.dev;
 154
 155                         if (rt_idev && (rt_idev->dev == dev || !dev) &&
 156                             rt_idev->dev != loopback_dev) {
 157                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 158                                 in6_dev_put(rt_idev);
 159                         }
 160
 161                         if (rt_dev && (rt_dev == dev || !dev) &&
 162                             rt_dev != loopback_dev) {
 163                                 rt->dst.dev = loopback_dev;
 164                                 dev_hold(rt->dst.dev);
 165                                 dev_put(rt_dev);
 166                         }
 167                 }
 168                 spin_unlock_bh(&ul->lock);
 169         }
 170 }
 171
 172 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 173 {
 174         return dst_metrics_write_ptr(rt->dst.from);
 175 }
 176
 177 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 178 {
 179         struct rt6_info *rt = (struct rt6_info *)dst;
 180
 181         if (rt->rt6i_flags & RTF_PCPU)
 182                 return rt6_pcpu_cow_metrics(rt);
 183         else if (rt->rt6i_flags & RTF_CACHE)
 184                 return NULL;
 185         else
 186                 return dst_cow_metrics_generic(dst, old);
 187 }
 188
 189 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 190                                              struct sk_buff *skb,
 191                                              const void *daddr)
 192 {
 193         struct in6_addr *p = &rt->rt6i_gateway;
 194
 195         if (!ipv6_addr_any(p))
 196                 return (const void *) p;
 197         else if (skb)
 198                 return &ipv6_hdr(skb)->daddr;
 199         return daddr;
 200 }
 201
 202 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 203                                           struct sk_buff *skb,
 204                                           const void *daddr)
 205 {
 206         struct rt6_info *rt = (struct rt6_info *) dst;
 207         struct neighbour *n;
 208
 209         daddr = choose_neigh_daddr(rt, skb, daddr);
 210         n = __ipv6_neigh_lookup(dst->dev, daddr);
 211         if (n)
 212                 return n;
 213         return neigh_create(&nd_tbl, daddr, dst->dev);
 214 }
 215
 216 static struct dst_ops ip6_dst_ops_template = {
 217         .family                 =       AF_INET6,
 218         .gc                     =       ip6_dst_gc,
 219         .gc_thresh              =       1024,
 220         .check                  =       ip6_dst_check,
 221         .default_advmss         =       ip6_default_advmss,
 222         .mtu                    =       ip6_mtu,
 223         .cow_metrics            =       ipv6_cow_metrics,
 224         .destroy                =       ip6_dst_destroy,
 225         .ifdown                 =       ip6_dst_ifdown,
 226         .negative_advice        =       ip6_negative_advice,
 227         .link_failure           =       ip6_link_failure,
 228         .update_pmtu            =       ip6_rt_update_pmtu,
 229         .redirect               =       rt6_do_redirect,
 230         .local_out              =       __ip6_local_out,
 231         .neigh_lookup           =       ip6_neigh_lookup,
 232 };
 233
 234 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 235 {
 236         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 237
 238         return mtu ? : dst->dev->mtu;
 239 }
 240
 241 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 242                                          struct sk_buff *skb, u32 mtu)
 243 {
 244 }
 245
 246 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 247                                       struct sk_buff *skb)
 248 {
 249 }
 250
 251 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
 252                                          unsigned long old)
 253 {
 254         return NULL;
 255 }
 256
 257 static struct dst_ops ip6_dst_blackhole_ops = {
 258         .family                 =       AF_INET6,
 259         .destroy                =       ip6_dst_destroy,
 260         .check                  =       ip6_dst_check,
 261         .mtu                    =       ip6_blackhole_mtu,
 262         .default_advmss         =       ip6_default_advmss,
 263         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 264         .redirect               =       ip6_rt_blackhole_redirect,
 265         .cow_metrics            =       ip6_rt_blackhole_cow_metrics,
 266         .neigh_lookup           =       ip6_neigh_lookup,
 267 };
 268
 269 static const u32 ip6_template_metrics[RTAX_MAX] = {
 270         [RTAX_HOPLIMIT - 1] = 0,
 271 };
 272
 273 static const struct rt6_info ip6_null_entry_template = {
 274         .dst = {
 275                 .__refcnt       = ATOMIC_INIT(1),
 276                 .__use          = 1,
 277                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 278                 .error          = -ENETUNREACH,
 279                 .input          = ip6_pkt_discard,
 280                 .output         = ip6_pkt_discard_out,
 281         },
 282         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 283         .rt6i_protocol  = RTPROT_KERNEL,
 284         .rt6i_metric    = ~(u32) 0,
 285         .rt6i_ref       = ATOMIC_INIT(1),
 286 };
 287
 288 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 289
 290 static const struct rt6_info ip6_prohibit_entry_template = {
 291         .dst = {
 292                 .__refcnt       = ATOMIC_INIT(1),
 293                 .__use          = 1,
 294                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 295                 .error          = -EACCES,
 296                 .input          = ip6_pkt_prohibit,
 297                 .output         = ip6_pkt_prohibit_out,
 298         },
 299         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 300         .rt6i_protocol  = RTPROT_KERNEL,
 301         .rt6i_metric    = ~(u32) 0,
 302         .rt6i_ref       = ATOMIC_INIT(1),
 303 };
 304
 305 static const struct rt6_info ip6_blk_hole_entry_template = {
 306         .dst = {
 307                 .__refcnt       = ATOMIC_INIT(1),
 308                 .__use          = 1,
 309                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 310                 .error          = -EINVAL,
 311                 .input          = dst_discard,
 312                 .output         = dst_discard_out,
 313         },
 314         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 315         .rt6i_protocol  = RTPROT_KERNEL,
 316         .rt6i_metric    = ~(u32) 0,
 317         .rt6i_ref       = ATOMIC_INIT(1),
 318 };
 319
 320 #endif
 321
 322 /* allocate dst with ip6_dst_ops */
 323 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 324                                         struct net_device *dev,
 325                                         int flags)
 326 {
 327         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 328                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 329
 330         if (rt) {
 331                 struct dst_entry *dst = &rt->dst;
 332
 333                 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 334                 INIT_LIST_HEAD(&rt->rt6i_siblings);
 335                 INIT_LIST_HEAD(&rt->rt6i_uncached);
 336         }
 337         return rt;
 338 }
 339
 340 static struct rt6_info *ip6_dst_alloc(struct net *net,
 341                                       struct net_device *dev,
 342                                       int flags)
 343 {
 344         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 345
 346         if (rt) {
 347                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 348                 if (rt->rt6i_pcpu) {
 349                         int cpu;
 350
 351                         for_each_possible_cpu(cpu) {
 352                                 struct rt6_info **p;
 353
 354                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 355                                 /* no one shares rt */
 356                                 *p =  NULL;
 357                         }
 358                 } else {
 359                         dst_destroy((struct dst_entry *)rt);
 360                         return NULL;
 361                 }
 362         }
 363
 364         return rt;
 365 }
 366
 367 static void ip6_dst_destroy(struct dst_entry *dst)
 368 {
 369         struct rt6_info *rt = (struct rt6_info *)dst;
 370         struct dst_entry *from = dst->from;
 371         struct inet6_dev *idev;
 372
 373         dst_destroy_metrics_generic(dst);
 374         free_percpu(rt->rt6i_pcpu);
 375         rt6_uncached_list_del(rt);
 376
 377         idev = rt->rt6i_idev;
 378         if (idev) {
 379                 rt->rt6i_idev = NULL;
 380                 in6_dev_put(idev);
 381         }
 382
 383         dst->from = NULL;
 384         dst_release(from);
 385 }
 386
 387 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 388                            int how)
 389 {
 390         struct rt6_info *rt = (struct rt6_info *)dst;
 391         struct inet6_dev *idev = rt->rt6i_idev;
 392         struct net_device *loopback_dev =
 393                 dev_net(dev)->loopback_dev;
 394
 395         if (dev != loopback_dev) {
 396                 if (idev && idev->dev == dev) {
 397                         struct inet6_dev *loopback_idev =
 398                                 in6_dev_get(loopback_dev);
 399                         if (loopback_idev) {
 400                                 rt->rt6i_idev = loopback_idev;
 401                                 in6_dev_put(idev);
 402                         }
 403                 }
 404         }
 405 }
 406
 407 static bool rt6_check_expired(const struct rt6_info *rt)
 408 {
 409         if (rt->rt6i_flags & RTF_EXPIRES) {
 410                 if (time_after(jiffies, rt->dst.expires))
 411                         return true;
 412         } else if (rt->dst.from) {
 413                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 414         }
 415         return false;
 416 }
 417
 418 /* Multipath route selection:
 419  *   Hash based function using packet header and flowlabel.
 420  * Adapted from fib_info_hashfn()
 421  */
 422 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 423                                const struct flowi6 *fl6)
 424 {
 425         return get_hash_from_flowi6(fl6) % candidate_count;
 426 }
 427
 428 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 429                                              struct flowi6 *fl6, int oif,
 430                                              int strict)
 431 {
 432         struct rt6_info *sibling, *next_sibling;
 433         int route_choosen;
 434
 435         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 436         /* Don't change the route, if route_choosen == 0
 437          * (siblings does not include ourself)
 438          */
 439         if (route_choosen)
 440                 list_for_each_entry_safe(sibling, next_sibling,
 441                                 &match->rt6i_siblings, rt6i_siblings) {
 442                         route_choosen--;
 443                         if (route_choosen == 0) {
 444                                 if (rt6_score_route(sibling, oif, strict) < 0)
 445                                         break;
 446                                 match = sibling;
 447                                 break;
 448                         }
 449                 }
 450         return match;
 451 }
 452
 453 /*
 454  *      Route lookup. Any table->tb6_lock is implied.
 455  */
 456
 457 static inline struct rt6_info *rt6_device_match(struct net *net,
 458                                                     struct rt6_info *rt,
 459                                                     const struct in6_addr *saddr,
 460                                                     int oif,
 461                                                     int flags)
 462 {
 463         struct rt6_info *local = NULL;
 464         struct rt6_info *sprt;
 465
 466         if (!oif && ipv6_addr_any(saddr))
 467                 goto out;
 468
 469         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 470                 struct net_device *dev = sprt->dst.dev;
 471
 472                 if (oif) {
 473                         if (dev->ifindex == oif)
 474                                 return sprt;
 475                         if (dev->flags & IFF_LOOPBACK) {
 476                                 if (!sprt->rt6i_idev ||
 477                                     sprt->rt6i_idev->dev->ifindex != oif) {
 478                                         if (flags & RT6_LOOKUP_F_IFACE)
 479                                                 continue;
 480                                         if (local &&
 481                                             local->rt6i_idev->dev->ifindex == oif)
 482                                                 continue;
 483                                 }
 484                                 local = sprt;
 485                         }
 486                 } else {
 487                         if (ipv6_chk_addr(net, saddr, dev,
 488                                           flags & RT6_LOOKUP_F_IFACE))
 489                                 return sprt;
 490                 }
 491         }
 492
 493         if (oif) {
 494                 if (local)
 495                         return local;
 496
 497                 if (flags & RT6_LOOKUP_F_IFACE)
 498                         return net->ipv6.ip6_null_entry;
 499         }
 500 out:
 501         return rt;
 502 }
 503
 504 #ifdef CONFIG_IPV6_ROUTER_PREF
 505 struct __rt6_probe_work {
 506         struct work_struct work;
 507         struct in6_addr target;
 508         struct net_device *dev;
 509 };
 510
 511 static void rt6_probe_deferred(struct work_struct *w)
 512 {
 513         struct in6_addr mcaddr;
 514         struct __rt6_probe_work *work =
 515                 container_of(w, struct __rt6_probe_work, work);
 516
 517         addrconf_addr_solict_mult(&work->target, &mcaddr);
 518         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, NULL);
 519         dev_put(work->dev);
 520         kfree(work);
 521 }
 522
 523 static void rt6_probe(struct rt6_info *rt)
 524 {
 525         struct __rt6_probe_work *work;
 526         struct neighbour *neigh;
 527         /*
 528          * Okay, this does not seem to be appropriate
 529          * for now, however, we need to check if it
 530          * is really so; aka Router Reachability Probing.
 531          *
 532          * Router Reachability Probe MUST be rate-limited
 533          * to no more than one per minute.
 534          */
 535         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 536                 return;
 537         rcu_read_lock_bh();
 538         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 539         if (neigh) {
 540                 if (neigh->nud_state & NUD_VALID)
 541                         goto out;
 542
 543                 work = NULL;
 544                 write_lock(&neigh->lock);
 545                 if (!(neigh->nud_state & NUD_VALID) &&
 546                     time_after(jiffies,
 547                                neigh->updated +
 548                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 549                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 550                         if (work)
 551                                 __neigh_set_probe_once(neigh);
 552                 }
 553                 write_unlock(&neigh->lock);
 554         } else {
 555                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 556         }
 557
 558         if (work) {
 559                 INIT_WORK(&work->work, rt6_probe_deferred);
 560                 work->target = rt->rt6i_gateway;
 561                 dev_hold(rt->dst.dev);
 562                 work->dev = rt->dst.dev;
 563                 schedule_work(&work->work);
 564         }
 565
 566 out:
 567         rcu_read_unlock_bh();
 568 }
 569 #else
 570 static inline void rt6_probe(struct rt6_info *rt)
 571 {
 572 }
 573 #endif
 574
 575 /*
 576  * Default Router Selection (RFC 2461 6.3.6)
 577  */
 578 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 579 {
 580         struct net_device *dev = rt->dst.dev;
 581         if (!oif || dev->ifindex == oif)
 582                 return 2;
 583         if ((dev->flags & IFF_LOOPBACK) &&
 584             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 585                 return 1;
 586         return 0;
 587 }
 588
 589 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 590 {
 591         struct neighbour *neigh;
 592         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 593
 594         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 595             !(rt->rt6i_flags & RTF_GATEWAY))
 596                 return RT6_NUD_SUCCEED;
 597
 598         rcu_read_lock_bh();
 599         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 600         if (neigh) {
 601                 read_lock(&neigh->lock);
 602                 if (neigh->nud_state & NUD_VALID)
 603                         ret = RT6_NUD_SUCCEED;
 604 #ifdef CONFIG_IPV6_ROUTER_PREF
 605                 else if (!(neigh->nud_state & NUD_FAILED))
 606                         ret = RT6_NUD_SUCCEED;
 607                 else
 608                         ret = RT6_NUD_FAIL_PROBE;
 609 #endif
 610                 read_unlock(&neigh->lock);
 611         } else {
 612                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 613                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 614         }
 615         rcu_read_unlock_bh();
 616
 617         return ret;
 618 }
 619
 620 static int rt6_score_route(struct rt6_info *rt, int oif,
 621                            int strict)
 622 {
 623         int m;
 624
 625         m = rt6_check_dev(rt, oif);
 626         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 627                 return RT6_NUD_FAIL_HARD;
 628 #ifdef CONFIG_IPV6_ROUTER_PREF
 629         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 630 #endif
 631         if (strict & RT6_LOOKUP_F_REACHABLE) {
 632                 int n = rt6_check_neigh(rt);
 633                 if (n < 0)
 634                         return n;
 635         }
 636         return m;
 637 }
 638
 639 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 640                                    int *mpri, struct rt6_info *match,
 641                                    bool *do_rr)
 642 {
 643         int m;
 644         bool match_do_rr = false;
 645         struct inet6_dev *idev = rt->rt6i_idev;
 646         struct net_device *dev = rt->dst.dev;
 647
 648         if (dev && !netif_carrier_ok(dev) &&
 649             idev->cnf.ignore_routes_with_linkdown)
 650                 goto out;
 651
 652         if (rt6_check_expired(rt))
 653                 goto out;
 654
 655         m = rt6_score_route(rt, oif, strict);
 656         if (m == RT6_NUD_FAIL_DO_RR) {
 657                 match_do_rr = true;
 658                 m = 0; /* lowest valid score */
 659         } else if (m == RT6_NUD_FAIL_HARD) {
 660                 goto out;
 661         }
 662
 663         if (strict & RT6_LOOKUP_F_REACHABLE)
 664                 rt6_probe(rt);
 665
 666         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 667         if (m > *mpri) {
 668                 *do_rr = match_do_rr;
 669                 *mpri = m;
 670                 match = rt;
 671         }
 672 out:
 673         return match;
 674 }
 675
 676 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 677                                      struct rt6_info *rr_head,
 678                                      u32 metric, int oif, int strict,
 679                                      bool *do_rr)
 680 {
 681         struct rt6_info *rt, *match, *cont;
 682         int mpri = -1;
 683
 684         match = NULL;
 685         cont = NULL;
 686         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 687                 if (rt->rt6i_metric != metric) {
 688                         cont = rt;
 689                         break;
 690                 }
 691
 692                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 693         }
 694
 695         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 696                 if (rt->rt6i_metric != metric) {
 697                         cont = rt;
 698                         break;
 699                 }
 700
 701                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 702         }
 703
 704         if (match || !cont)
 705                 return match;
 706
 707         for (rt = cont; rt; rt = rt->dst.rt6_next)
 708                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 709
 710         return match;
 711 }
 712
 713 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 714 {
 715         struct rt6_info *match, *rt0;
 716         struct net *net;
 717         bool do_rr = false;
 718
 719         rt0 = fn->rr_ptr;
 720         if (!rt0)
 721                 fn->rr_ptr = rt0 = fn->leaf;
 722
 723         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 724                              &do_rr);
 725
 726         if (do_rr) {
 727                 struct rt6_info *next = rt0->dst.rt6_next;
 728
 729                 /* no entries matched; do round-robin */
 730                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 731                         next = fn->leaf;
 732
 733                 if (next != rt0)
 734                         fn->rr_ptr = next;
 735         }
 736
 737         net = dev_net(rt0->dst.dev);
 738         return match ? match : net->ipv6.ip6_null_entry;
 739 }
 740
 741 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 742 {
 743         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 744 }
 745
 746 #ifdef CONFIG_IPV6_ROUTE_INFO
 747 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 748                   const struct in6_addr *gwaddr)
 749 {
 750         struct net *net = dev_net(dev);
 751         struct route_info *rinfo = (struct route_info *) opt;
 752         struct in6_addr prefix_buf, *prefix;
 753         unsigned int pref;
 754         unsigned long lifetime;
 755         struct rt6_info *rt;
 756
 757         if (len < sizeof(struct route_info)) {
 758                 return -EINVAL;
 759         }
 760
 761         /* Sanity check for prefix_len and length */
 762         if (rinfo->length > 3) {
 763                 return -EINVAL;
 764         } else if (rinfo->prefix_len > 128) {
 765                 return -EINVAL;
 766         } else if (rinfo->prefix_len > 64) {
 767                 if (rinfo->length < 2) {
 768                         return -EINVAL;
 769                 }
 770         } else if (rinfo->prefix_len > 0) {
 771                 if (rinfo->length < 1) {
 772                         return -EINVAL;
 773                 }
 774         }
 775
 776         pref = rinfo->route_pref;
 777         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 778                 return -EINVAL;
 779
 780         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 781
 782         if (rinfo->length == 3)
 783                 prefix = (struct in6_addr *)rinfo->prefix;
 784         else {
 785                 /* this function is safe */
 786                 ipv6_addr_prefix(&prefix_buf,
 787                                  (struct in6_addr *)rinfo->prefix,
 788                                  rinfo->prefix_len);
 789                 prefix = &prefix_buf;
 790         }
 791
 792         if (rinfo->prefix_len == 0)
 793                 rt = rt6_get_dflt_router(gwaddr, dev);
 794         else
 795                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 796                                         gwaddr, dev->ifindex);
 797
 798         if (rt && !lifetime) {
 799                 ip6_del_rt(rt);
 800                 rt = NULL;
 801         }
 802
 803         if (!rt && lifetime)
 804                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 805                                         pref);
 806         else if (rt)
 807                 rt->rt6i_flags = RTF_ROUTEINFO |
 808                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 809
 810         if (rt) {
 811                 if (!addrconf_finite_timeout(lifetime))
 812                         rt6_clean_expires(rt);
 813                 else
 814                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 815
 816                 ip6_rt_put(rt);
 817         }
 818         return 0;
 819 }
 820 #endif
 821
 822 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 823                                         struct in6_addr *saddr)
 824 {
 825         struct fib6_node *pn;
 826         while (1) {
 827                 if (fn->fn_flags & RTN_TL_ROOT)
 828                         return NULL;
 829                 pn = fn->parent;
 830                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 831                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 832                 else
 833                         fn = pn;
 834                 if (fn->fn_flags & RTN_RTINFO)
 835                         return fn;
 836         }
 837 }
 838
 839 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 840                                              struct fib6_table *table,
 841                                              struct flowi6 *fl6, int flags)
 842 {
 843         struct fib6_node *fn;
 844         struct rt6_info *rt;
 845
 846         read_lock_bh(&table->tb6_lock);
 847         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 848 restart:
 849         rt = fn->leaf;
 850         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 851         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 852                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 853         if (rt == net->ipv6.ip6_null_entry) {
 854                 fn = fib6_backtrack(fn, &fl6->saddr);
 855                 if (fn)
 856                         goto restart;
 857         }
 858         dst_use(&rt->dst, jiffies);
 859         read_unlock_bh(&table->tb6_lock);
 860         return rt;
 861
 862 }
 863
 864 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 865                                     int flags)
 866 {
 867         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 868 }
 869 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 870
 871 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 872                             const struct in6_addr *saddr, int oif, int strict)
 873 {
 874         struct flowi6 fl6 = {
 875                 .flowi6_oif = oif,
 876                 .daddr = *daddr,
 877         };
 878         struct dst_entry *dst;
 879         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 880
 881         if (saddr) {
 882                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 883                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 884         }
 885
 886         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 887         if (dst->error == 0)
 888                 return (struct rt6_info *) dst;
 889
 890         dst_release(dst);
 891
 892         return NULL;
 893 }
 894 EXPORT_SYMBOL(rt6_lookup);
 895
 896 /* ip6_ins_rt is called with FREE table->tb6_lock.
 897    It takes new route entry, the addition fails by any reason the
 898    route is freed. In any case, if caller does not hold it, it may
 899    be destroyed.
 900  */
 901
 902 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 903                         struct mx6_config *mxc)
 904 {
 905         int err;
 906         struct fib6_table *table;
 907
 908         table = rt->rt6i_table;
 909         write_lock_bh(&table->tb6_lock);
 910         err = fib6_add(&table->tb6_root, rt, info, mxc);
 911         write_unlock_bh(&table->tb6_lock);
 912
 913         return err;
 914 }
 915
 916 int ip6_ins_rt(struct rt6_info *rt)
 917 {
 918         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 919         struct mx6_config mxc = { .mx = NULL, };
 920
 921         return __ip6_ins_rt(rt, &info, &mxc);
 922 }
 923
 924 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 925                                            const struct in6_addr *daddr,
 926                                            const struct in6_addr *saddr)
 927 {
 928         struct rt6_info *rt;
 929
 930         /*
 931          *      Clone the route.
 932          */
 933
 934         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 935                 ort = (struct rt6_info *)ort->dst.from;
 936
 937         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 938
 939         if (!rt)
 940                 return NULL;
 941
 942         ip6_rt_copy_init(rt, ort);
 943         rt->rt6i_flags |= RTF_CACHE;
 944         rt->rt6i_metric = 0;
 945         rt->dst.flags |= DST_HOST;
 946         rt->rt6i_dst.addr = *daddr;
 947         rt->rt6i_dst.plen = 128;
 948
 949         if (!rt6_is_gw_or_nonexthop(ort)) {
 950                 if (ort->rt6i_dst.plen != 128 &&
 951                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 952                         rt->rt6i_flags |= RTF_ANYCAST;
 953 #ifdef CONFIG_IPV6_SUBTREES
 954                 if (rt->rt6i_src.plen && saddr) {
 955                         rt->rt6i_src.addr = *saddr;
 956                         rt->rt6i_src.plen = 128;
 957                 }
 958 #endif
 959         }
 960
 961         return rt;
 962 }
 963
 964 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 965 {
 966         struct rt6_info *pcpu_rt;
 967
 968         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 969                                   rt->dst.dev, rt->dst.flags);
 970
 971         if (!pcpu_rt)
 972                 return NULL;
 973         ip6_rt_copy_init(pcpu_rt, rt);
 974         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 975         pcpu_rt->rt6i_flags |= RTF_PCPU;
 976         return pcpu_rt;
 977 }
 978
 979 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 980 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 981 {
 982         struct rt6_info *pcpu_rt, **p;
 983
 984         p = this_cpu_ptr(rt->rt6i_pcpu);
 985         pcpu_rt = *p;
 986
 987         if (pcpu_rt) {
 988                 dst_hold(&pcpu_rt->dst);
 989                 rt6_dst_from_metrics_check(pcpu_rt);
 990         }
 991         return pcpu_rt;
 992 }
 993
 994 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
 995 {
 996         struct fib6_table *table = rt->rt6i_table;
 997         struct rt6_info *pcpu_rt, *prev, **p;
 998
 999         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1000         if (!pcpu_rt) {
1001                 struct net *net = dev_net(rt->dst.dev);
1002
1003                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1004                 return net->ipv6.ip6_null_entry;
1005         }
1006
1007         read_lock_bh(&table->tb6_lock);
1008         if (rt->rt6i_pcpu) {
1009                 p = this_cpu_ptr(rt->rt6i_pcpu);
1010                 prev = cmpxchg(p, NULL, pcpu_rt);
1011                 if (prev) {
1012                         /* If someone did it before us, return prev instead */
1013                         dst_destroy(&pcpu_rt->dst);
1014                         pcpu_rt = prev;
1015                 }
1016         } else {
1017                 /* rt has been removed from the fib6 tree
1018                  * before we have a chance to acquire the read_lock.
1019                  * In this case, don't brother to create a pcpu rt
1020                  * since rt is going away anyway.  The next
1021                  * dst_check() will trigger a re-lookup.
1022                  */
1023                 dst_destroy(&pcpu_rt->dst);
1024                 pcpu_rt = rt;
1025         }
1026         dst_hold(&pcpu_rt->dst);
1027         rt6_dst_from_metrics_check(pcpu_rt);
1028         read_unlock_bh(&table->tb6_lock);
1029         return pcpu_rt;
1030 }
1031
1032 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1033                                       struct flowi6 *fl6, int flags)
1034 {
1035         struct fib6_node *fn, *saved_fn;
1036         struct rt6_info *rt;
1037         int strict = 0;
1038
1039         strict |= flags & RT6_LOOKUP_F_IFACE;
1040         if (net->ipv6.devconf_all->forwarding == 0)
1041                 strict |= RT6_LOOKUP_F_REACHABLE;
1042
1043         read_lock_bh(&table->tb6_lock);
1044
1045         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1046         saved_fn = fn;
1047
1048         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1049                 oif = 0;
1050
1051 redo_rt6_select:
1052         rt = rt6_select(fn, oif, strict);
1053         if (rt->rt6i_nsiblings)
1054                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1055         if (rt == net->ipv6.ip6_null_entry) {
1056                 fn = fib6_backtrack(fn, &fl6->saddr);
1057                 if (fn)
1058                         goto redo_rt6_select;
1059                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1060                         /* also consider unreachable route */
1061                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1062                         fn = saved_fn;
1063                         goto redo_rt6_select;
1064                 }
1065         }
1066
1067
1068         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1069                 dst_use(&rt->dst, jiffies);
1070                 read_unlock_bh(&table->tb6_lock);
1071
1072                 rt6_dst_from_metrics_check(rt);
1073                 return rt;
1074         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1075                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1076                 /* Create a RTF_CACHE clone which will not be
1077                  * owned by the fib6 tree.  It is for the special case where
1078                  * the daddr in the skb during the neighbor look-up is different
1079                  * from the fl6->daddr used to look-up route here.
1080                  */
1081
1082                 struct rt6_info *uncached_rt;
1083
1084                 dst_use(&rt->dst, jiffies);
1085                 read_unlock_bh(&table->tb6_lock);
1086
1087                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1088                 dst_release(&rt->dst);
1089
1090                 if (uncached_rt)
1091                         rt6_uncached_list_add(uncached_rt);
1092                 else
1093                         uncached_rt = net->ipv6.ip6_null_entry;
1094
1095                 dst_hold(&uncached_rt->dst);
1096                 return uncached_rt;
1097
1098         } else {
1099                 /* Get a percpu copy */
1100
1101                 struct rt6_info *pcpu_rt;
1102
1103                 rt->dst.lastuse = jiffies;
1104                 rt->dst.__use++;
1105                 pcpu_rt = rt6_get_pcpu_route(rt);
1106
1107                 if (pcpu_rt) {
1108                         read_unlock_bh(&table->tb6_lock);
1109                 } else {
1110                         /* We have to do the read_unlock first
1111                          * because rt6_make_pcpu_route() may trigger
1112                          * ip6_dst_gc() which will take the write_lock.
1113                          */
1114                         dst_hold(&rt->dst);
1115                         read_unlock_bh(&table->tb6_lock);
1116                         pcpu_rt = rt6_make_pcpu_route(rt);
1117                         dst_release(&rt->dst);
1118                 }
1119
1120                 return pcpu_rt;
1121
1122         }
1123 }
1124
1125 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1126                                             struct flowi6 *fl6, int flags)
1127 {
1128         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1129 }
1130
1131 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1132                                                 struct net_device *dev,
1133                                                 struct flowi6 *fl6, int flags)
1134 {
1135         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1136                 flags |= RT6_LOOKUP_F_IFACE;
1137
1138         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1139 }
1140
1141 void ip6_route_input(struct sk_buff *skb)
1142 {
1143         const struct ipv6hdr *iph = ipv6_hdr(skb);
1144         struct net *net = dev_net(skb->dev);
1145         int flags = RT6_LOOKUP_F_HAS_SADDR;
1146         struct ip_tunnel_info *tun_info;
1147         struct flowi6 fl6 = {
1148                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1149                 .daddr = iph->daddr,
1150                 .saddr = iph->saddr,
1151                 .flowlabel = ip6_flowinfo(iph),
1152                 .flowi6_mark = skb->mark,
1153                 .flowi6_proto = iph->nexthdr,
1154         };
1155
1156         tun_info = skb_tunnel_info(skb);
1157         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1158                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1159         skb_dst_drop(skb);
1160         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1161 }
1162
1163 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1164                                              struct flowi6 *fl6, int flags)
1165 {
1166         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1167 }
1168
1169 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1170                                     struct flowi6 *fl6)
1171 {
1172         struct dst_entry *dst;
1173         int flags = 0;
1174
1175         dst = l3mdev_rt6_dst_by_oif(net, fl6);
1176         if (dst)
1177                 return dst;
1178
1179         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1180
1181         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1182             fl6->flowi6_oif)
1183                 flags |= RT6_LOOKUP_F_IFACE;
1184
1185         if (!ipv6_addr_any(&fl6->saddr))
1186                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1187         else if (sk)
1188                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1189
1190         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1191 }
1192 EXPORT_SYMBOL(ip6_route_output);
1193
1194 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1195 {
1196         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1197         struct dst_entry *new = NULL;
1198
1199         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1200         if (rt) {
1201                 new = &rt->dst;
1202
1203                 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1204
1205                 new->__use = 1;
1206                 new->input = dst_discard;
1207                 new->output = dst_discard_out;
1208
1209                 if (dst_metrics_read_only(&ort->dst))
1210                         new->_metrics = ort->dst._metrics;
1211                 else
1212                         dst_copy_metrics(new, &ort->dst);
1213                 rt->rt6i_idev = ort->rt6i_idev;
1214                 if (rt->rt6i_idev)
1215                         in6_dev_hold(rt->rt6i_idev);
1216
1217                 rt->rt6i_gateway = ort->rt6i_gateway;
1218                 rt->rt6i_flags = ort->rt6i_flags;
1219                 rt->rt6i_metric = 0;
1220
1221                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1222 #ifdef CONFIG_IPV6_SUBTREES
1223                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1224 #endif
1225
1226                 dst_free(new);
1227         }
1228
1229         dst_release(dst_orig);
1230         return new ? new : ERR_PTR(-ENOMEM);
1231 }
1232
1233 /*
1234  *      Destination cache support functions
1235  */
1236
1237 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1238 {
1239         if (rt->dst.from &&
1240             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1241                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1242 }
1243
1244 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1245 {
1246         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1247                 return NULL;
1248
1249         if (rt6_check_expired(rt))
1250                 return NULL;
1251
1252         return &rt->dst;
1253 }
1254
1255 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1256 {
1257         if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1258             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1259                 return &rt->dst;
1260         else
1261                 return NULL;
1262 }
1263
1264 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1265 {
1266         struct rt6_info *rt;
1267
1268         rt = (struct rt6_info *) dst;
1269
1270         /* All IPV6 dsts are created with ->obsolete set to the value
1271          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1272          * into this function always.
1273          */
1274
1275         rt6_dst_from_metrics_check(rt);
1276
1277         if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1278                 return rt6_dst_from_check(rt, cookie);
1279         else
1280                 return rt6_check(rt, cookie);
1281 }
1282
1283 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1284 {
1285         struct rt6_info *rt = (struct rt6_info *) dst;
1286
1287         if (rt) {
1288                 if (rt->rt6i_flags & RTF_CACHE) {
1289                         if (rt6_check_expired(rt)) {
1290                                 ip6_del_rt(rt);
1291                                 dst = NULL;
1292                         }
1293                 } else {
1294                         dst_release(dst);
1295                         dst = NULL;
1296                 }
1297         }
1298         return dst;
1299 }
1300
1301 static void ip6_link_failure(struct sk_buff *skb)
1302 {
1303         struct rt6_info *rt;
1304
1305         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1306
1307         rt = (struct rt6_info *) skb_dst(skb);
1308         if (rt) {
1309                 if (rt->rt6i_flags & RTF_CACHE) {
1310                         dst_hold(&rt->dst);
1311                         ip6_del_rt(rt);
1312                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1313                         rt->rt6i_node->fn_sernum = -1;
1314                 }
1315         }
1316 }
1317
1318 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1319 {
1320         struct net *net = dev_net(rt->dst.dev);
1321
1322         rt->rt6i_flags |= RTF_MODIFIED;
1323         rt->rt6i_pmtu = mtu;
1324         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1325 }
1326
1327 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1328                                  const struct ipv6hdr *iph, u32 mtu)
1329 {
1330         struct rt6_info *rt6 = (struct rt6_info *)dst;
1331
1332         if (rt6->rt6i_flags & RTF_LOCAL)
1333                 return;
1334
1335         dst_confirm(dst);
1336         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1337         if (mtu >= dst_mtu(dst))
1338                 return;
1339
1340         if (rt6->rt6i_flags & RTF_CACHE) {
1341                 rt6_do_update_pmtu(rt6, mtu);
1342         } else {
1343                 const struct in6_addr *daddr, *saddr;
1344                 struct rt6_info *nrt6;
1345
1346                 if (iph) {
1347                         daddr = &iph->daddr;
1348                         saddr = &iph->saddr;
1349                 } else if (sk) {
1350                         daddr = &sk->sk_v6_daddr;
1351                         saddr = &inet6_sk(sk)->saddr;
1352                 } else {
1353                         return;
1354                 }
1355                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1356                 if (nrt6) {
1357                         rt6_do_update_pmtu(nrt6, mtu);
1358
1359                         /* ip6_ins_rt(nrt6) will bump the
1360                          * rt6->rt6i_node->fn_sernum
1361                          * which will fail the next rt6_check() and
1362                          * invalidate the sk->sk_dst_cache.
1363                          */
1364                         ip6_ins_rt(nrt6);
1365                 }
1366         }
1367 }
1368
1369 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1370                                struct sk_buff *skb, u32 mtu)
1371 {
1372         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1373 }
1374
1375 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1376                      int oif, u32 mark)
1377 {
1378         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1379         struct dst_entry *dst;
1380         struct flowi6 fl6;
1381
1382         memset(&fl6, 0, sizeof(fl6));
1383         fl6.flowi6_oif = oif;
1384         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1385         fl6.daddr = iph->daddr;
1386         fl6.saddr = iph->saddr;
1387         fl6.flowlabel = ip6_flowinfo(iph);
1388
1389         dst = ip6_route_output(net, NULL, &fl6);
1390         if (!dst->error)
1391                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1392         dst_release(dst);
1393 }
1394 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1395
1396 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1397 {
1398         ip6_update_pmtu(skb, sock_net(sk), mtu,
1399                         sk->sk_bound_dev_if, sk->sk_mark);
1400 }
1401 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1402
1403 /* Handle redirects */
1404 struct ip6rd_flowi {
1405         struct flowi6 fl6;
1406         struct in6_addr gateway;
1407 };
1408
1409 static struct rt6_info *__ip6_route_redirect(struct net *net,
1410                                              struct fib6_table *table,
1411                                              struct flowi6 *fl6,
1412                                              int flags)
1413 {
1414         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1415         struct rt6_info *rt;
1416         struct fib6_node *fn;
1417
1418         /* Get the "current" route for this destination and
1419          * check if the redirect has come from approriate router.
1420          *
1421          * RFC 4861 specifies that redirects should only be
1422          * accepted if they come from the nexthop to the target.
1423          * Due to the way the routes are chosen, this notion
1424          * is a bit fuzzy and one might need to check all possible
1425          * routes.
1426          */
1427
1428         read_lock_bh(&table->tb6_lock);
1429         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1430 restart:
1431         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1432                 if (rt6_check_expired(rt))
1433                         continue;
1434                 if (rt->dst.error)
1435                         break;
1436                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1437                         continue;
1438                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1439                         continue;
1440                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1441                         continue;
1442                 break;
1443         }
1444
1445         if (!rt)
1446                 rt = net->ipv6.ip6_null_entry;
1447         else if (rt->dst.error) {
1448                 rt = net->ipv6.ip6_null_entry;
1449                 goto out;
1450         }
1451
1452         if (rt == net->ipv6.ip6_null_entry) {
1453                 fn = fib6_backtrack(fn, &fl6->saddr);
1454                 if (fn)
1455                         goto restart;
1456         }
1457
1458 out:
1459         dst_hold(&rt->dst);
1460
1461         read_unlock_bh(&table->tb6_lock);
1462
1463         return rt;
1464 };
1465
1466 static struct dst_entry *ip6_route_redirect(struct net *net,
1467                                         const struct flowi6 *fl6,
1468                                         const struct in6_addr *gateway)
1469 {
1470         int flags = RT6_LOOKUP_F_HAS_SADDR;
1471         struct ip6rd_flowi rdfl;
1472
1473         rdfl.fl6 = *fl6;
1474         rdfl.gateway = *gateway;
1475
1476         return fib6_rule_lookup(net, &rdfl.fl6,
1477                                 flags, __ip6_route_redirect);
1478 }
1479
1480 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1481 {
1482         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1483         struct dst_entry *dst;
1484         struct flowi6 fl6;
1485
1486         memset(&fl6, 0, sizeof(fl6));
1487         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1488         fl6.flowi6_oif = oif;
1489         fl6.flowi6_mark = mark;
1490         fl6.daddr = iph->daddr;
1491         fl6.saddr = iph->saddr;
1492         fl6.flowlabel = ip6_flowinfo(iph);
1493
1494         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1495         rt6_do_redirect(dst, NULL, skb);
1496         dst_release(dst);
1497 }
1498 EXPORT_SYMBOL_GPL(ip6_redirect);
1499
1500 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1501                             u32 mark)
1502 {
1503         const struct ipv6hdr *iph = ipv6_hdr(skb);
1504         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1505         struct dst_entry *dst;
1506         struct flowi6 fl6;
1507
1508         memset(&fl6, 0, sizeof(fl6));
1509         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1510         fl6.flowi6_oif = oif;
1511         fl6.flowi6_mark = mark;
1512         fl6.daddr = msg->dest;
1513         fl6.saddr = iph->daddr;
1514
1515         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1516         rt6_do_redirect(dst, NULL, skb);
1517         dst_release(dst);
1518 }
1519
1520 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1521 {
1522         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1523 }
1524 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1525
1526 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1527 {
1528         struct net_device *dev = dst->dev;
1529         unsigned int mtu = dst_mtu(dst);
1530         struct net *net = dev_net(dev);
1531
1532         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1533
1534         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1535                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1536
1537         /*
1538          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1539          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1540          * IPV6_MAXPLEN is also valid and means: "any MSS,
1541          * rely only on pmtu discovery"
1542          */
1543         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1544                 mtu = IPV6_MAXPLEN;
1545         return mtu;
1546 }
1547
1548 static unsigned int ip6_mtu(const struct dst_entry *dst)
1549 {
1550         const struct rt6_info *rt = (const struct rt6_info *)dst;
1551         unsigned int mtu = rt->rt6i_pmtu;
1552         struct inet6_dev *idev;
1553
1554         if (mtu)
1555                 goto out;
1556
1557         mtu = dst_metric_raw(dst, RTAX_MTU);
1558         if (mtu)
1559                 goto out;
1560
1561         mtu = IPV6_MIN_MTU;
1562
1563         rcu_read_lock();
1564         idev = __in6_dev_get(dst->dev);
1565         if (idev)
1566                 mtu = idev->cnf.mtu6;
1567         rcu_read_unlock();
1568
1569 out:
1570         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1571 }
1572
1573 static struct dst_entry *icmp6_dst_gc_list;
1574 static DEFINE_SPINLOCK(icmp6_dst_lock);
1575
1576 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1577                                   struct flowi6 *fl6)
1578 {
1579         struct dst_entry *dst;
1580         struct rt6_info *rt;
1581         struct inet6_dev *idev = in6_dev_get(dev);
1582         struct net *net = dev_net(dev);
1583
1584         if (unlikely(!idev))
1585                 return ERR_PTR(-ENODEV);
1586
1587         rt = ip6_dst_alloc(net, dev, 0);
1588         if (unlikely(!rt)) {
1589                 in6_dev_put(idev);
1590                 dst = ERR_PTR(-ENOMEM);
1591                 goto out;
1592         }
1593
1594         rt->dst.flags |= DST_HOST;
1595         rt->dst.output  = ip6_output;
1596         atomic_set(&rt->dst.__refcnt, 1);
1597         rt->rt6i_gateway  = fl6->daddr;
1598         rt->rt6i_dst.addr = fl6->daddr;
1599         rt->rt6i_dst.plen = 128;
1600         rt->rt6i_idev     = idev;
1601         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1602
1603         spin_lock_bh(&icmp6_dst_lock);
1604         rt->dst.next = icmp6_dst_gc_list;
1605         icmp6_dst_gc_list = &rt->dst;
1606         spin_unlock_bh(&icmp6_dst_lock);
1607
1608         fib6_force_start_gc(net);
1609
1610         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1611
1612 out:
1613         return dst;
1614 }
1615
1616 int icmp6_dst_gc(void)
1617 {
1618         struct dst_entry *dst, **pprev;
1619         int more = 0;
1620
1621         spin_lock_bh(&icmp6_dst_lock);
1622         pprev = &icmp6_dst_gc_list;
1623
1624         while ((dst = *pprev) != NULL) {
1625                 if (!atomic_read(&dst->__refcnt)) {
1626                         *pprev = dst->next;
1627                         dst_free(dst);
1628                 } else {
1629                         pprev = &dst->next;
1630                         ++more;
1631                 }
1632         }
1633
1634         spin_unlock_bh(&icmp6_dst_lock);
1635
1636         return more;
1637 }
1638
1639 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1640                             void *arg)
1641 {
1642         struct dst_entry *dst, **pprev;
1643
1644         spin_lock_bh(&icmp6_dst_lock);
1645         pprev = &icmp6_dst_gc_list;
1646         while ((dst = *pprev) != NULL) {
1647                 struct rt6_info *rt = (struct rt6_info *) dst;
1648                 if (func(rt, arg)) {
1649                         *pprev = dst->next;
1650                         dst_free(dst);
1651                 } else {
1652                         pprev = &dst->next;
1653                 }
1654         }
1655         spin_unlock_bh(&icmp6_dst_lock);
1656 }
1657
1658 static int ip6_dst_gc(struct dst_ops *ops)
1659 {
1660         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1661         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1662         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1663         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1664         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1665         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1666         int entries;
1667
1668         entries = dst_entries_get_fast(ops);
1669         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1670             entries <= rt_max_size)
1671                 goto out;
1672
1673         net->ipv6.ip6_rt_gc_expire++;
1674         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1675         entries = dst_entries_get_slow(ops);
1676         if (entries < ops->gc_thresh)
1677                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1678 out:
1679         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1680         return entries > rt_max_size;
1681 }
1682
1683 static int ip6_convert_metrics(struct mx6_config *mxc,
1684                                const struct fib6_config *cfg)
1685 {
1686         bool ecn_ca = false;
1687         struct nlattr *nla;
1688         int remaining;
1689         u32 *mp;
1690
1691         if (!cfg->fc_mx)
1692                 return 0;
1693
1694         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1695         if (unlikely(!mp))
1696                 return -ENOMEM;
1697
1698         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1699                 int type = nla_type(nla);
1700                 u32 val;
1701
1702                 if (!type)
1703                         continue;
1704                 if (unlikely(type > RTAX_MAX))
1705                         goto err;
1706
1707                 if (type == RTAX_CC_ALGO) {
1708                         char tmp[TCP_CA_NAME_MAX];
1709
1710                         nla_strlcpy(tmp, nla, sizeof(tmp));
1711                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1712                         if (val == TCP_CA_UNSPEC)
1713                                 goto err;
1714                 } else {
1715                         val = nla_get_u32(nla);
1716                 }
1717                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1718                         goto err;
1719
1720                 mp[type - 1] = val;
1721                 __set_bit(type - 1, mxc->mx_valid);
1722         }
1723
1724         if (ecn_ca) {
1725                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1726                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1727         }
1728
1729         mxc->mx = mp;
1730         return 0;
1731  err:
1732         kfree(mp);
1733         return -EINVAL;
1734 }
1735
1736 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1737 {
1738         struct net *net = cfg->fc_nlinfo.nl_net;
1739         struct rt6_info *rt = NULL;
1740         struct net_device *dev = NULL;
1741         struct inet6_dev *idev = NULL;
1742         struct fib6_table *table;
1743         int addr_type;
1744         int err = -EINVAL;
1745
1746         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1747                 goto out;
1748 #ifndef CONFIG_IPV6_SUBTREES
1749         if (cfg->fc_src_len)
1750                 goto out;
1751 #endif
1752         if (cfg->fc_ifindex) {
1753                 err = -ENODEV;
1754                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1755                 if (!dev)
1756                         goto out;
1757                 idev = in6_dev_get(dev);
1758                 if (!idev)
1759                         goto out;
1760         }
1761
1762         if (cfg->fc_metric == 0)
1763                 cfg->fc_metric = IP6_RT_PRIO_USER;
1764
1765         err = -ENOBUFS;
1766         if (cfg->fc_nlinfo.nlh &&
1767             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1768                 table = fib6_get_table(net, cfg->fc_table);
1769                 if (!table) {
1770                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1771                         table = fib6_new_table(net, cfg->fc_table);
1772                 }
1773         } else {
1774                 table = fib6_new_table(net, cfg->fc_table);
1775         }
1776
1777         if (!table)
1778                 goto out;
1779
1780         rt = ip6_dst_alloc(net, NULL,
1781                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1782
1783         if (!rt) {
1784                 err = -ENOMEM;
1785                 goto out;
1786         }
1787
1788         if (cfg->fc_flags & RTF_EXPIRES)
1789                 rt6_set_expires(rt, jiffies +
1790                                 clock_t_to_jiffies(cfg->fc_expires));
1791         else
1792                 rt6_clean_expires(rt);
1793
1794         if (cfg->fc_protocol == RTPROT_UNSPEC)
1795                 cfg->fc_protocol = RTPROT_BOOT;
1796         rt->rt6i_protocol = cfg->fc_protocol;
1797
1798         addr_type = ipv6_addr_type(&cfg->fc_dst);
1799
1800         if (addr_type & IPV6_ADDR_MULTICAST)
1801                 rt->dst.input = ip6_mc_input;
1802         else if (cfg->fc_flags & RTF_LOCAL)
1803                 rt->dst.input = ip6_input;
1804         else
1805                 rt->dst.input = ip6_forward;
1806
1807         rt->dst.output = ip6_output;
1808
1809         if (cfg->fc_encap) {
1810                 struct lwtunnel_state *lwtstate;
1811
1812                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1813                                            cfg->fc_encap, AF_INET6, cfg,
1814                                            &lwtstate);
1815                 if (err)
1816                         goto out;
1817                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1818                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1819                         rt->dst.lwtstate->orig_output = rt->dst.output;
1820                         rt->dst.output = lwtunnel_output;
1821                 }
1822                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1823                         rt->dst.lwtstate->orig_input = rt->dst.input;
1824                         rt->dst.input = lwtunnel_input;
1825                 }
1826         }
1827
1828         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1829         rt->rt6i_dst.plen = cfg->fc_dst_len;
1830         if (rt->rt6i_dst.plen == 128)
1831                 rt->dst.flags |= DST_HOST;
1832
1833 #ifdef CONFIG_IPV6_SUBTREES
1834         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1835         rt->rt6i_src.plen = cfg->fc_src_len;
1836 #endif
1837
1838         rt->rt6i_metric = cfg->fc_metric;
1839
1840         /* We cannot add true routes via loopback here,
1841            they would result in kernel looping; promote them to reject routes
1842          */
1843         if ((cfg->fc_flags & RTF_REJECT) ||
1844             (dev && (dev->flags & IFF_LOOPBACK) &&
1845              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1846              !(cfg->fc_flags & RTF_LOCAL))) {
1847                 /* hold loopback dev/idev if we haven't done so. */
1848                 if (dev != net->loopback_dev) {
1849                         if (dev) {
1850                                 dev_put(dev);
1851                                 in6_dev_put(idev);
1852                         }
1853                         dev = net->loopback_dev;
1854                         dev_hold(dev);
1855                         idev = in6_dev_get(dev);
1856                         if (!idev) {
1857                                 err = -ENODEV;
1858                                 goto out;
1859                         }
1860                 }
1861                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1862                 switch (cfg->fc_type) {
1863                 case RTN_BLACKHOLE:
1864                         rt->dst.error = -EINVAL;
1865                         rt->dst.output = dst_discard_out;
1866                         rt->dst.input = dst_discard;
1867                         break;
1868                 case RTN_PROHIBIT:
1869                         rt->dst.error = -EACCES;
1870                         rt->dst.output = ip6_pkt_prohibit_out;
1871                         rt->dst.input = ip6_pkt_prohibit;
1872                         break;
1873                 case RTN_THROW:
1874                 case RTN_UNREACHABLE:
1875                 default:
1876                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1877                                         : (cfg->fc_type == RTN_UNREACHABLE)
1878                                         ? -EHOSTUNREACH : -ENETUNREACH;
1879                         rt->dst.output = ip6_pkt_discard_out;
1880                         rt->dst.input = ip6_pkt_discard;
1881                         break;
1882                 }
1883                 goto install_route;
1884         }
1885
1886         if (cfg->fc_flags & RTF_GATEWAY) {
1887                 const struct in6_addr *gw_addr;
1888                 int gwa_type;
1889
1890                 gw_addr = &cfg->fc_gateway;
1891                 gwa_type = ipv6_addr_type(gw_addr);
1892
1893                 /* if gw_addr is local we will fail to detect this in case
1894                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1895                  * will return already-added prefix route via interface that
1896                  * prefix route was assigned to, which might be non-loopback.
1897                  */
1898                 err = -EINVAL;
1899                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1900                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1901                                             dev : NULL, 0, 0))
1902                         goto out;
1903
1904                 rt->rt6i_gateway = *gw_addr;
1905
1906                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1907                         struct rt6_info *grt;
1908
1909                         /* IPv6 strictly inhibits using not link-local
1910                            addresses as nexthop address.
1911                            Otherwise, router will not able to send redirects.
1912                            It is very good, but in some (rare!) circumstances
1913                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1914                            some exceptions. --ANK
1915                          */
1916                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1917                                 goto out;
1918
1919                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1920
1921                         err = -EHOSTUNREACH;
1922                         if (!grt)
1923                                 goto out;
1924                         if (dev) {
1925                                 if (dev != grt->dst.dev) {
1926                                         ip6_rt_put(grt);
1927                                         goto out;
1928                                 }
1929                         } else {
1930                                 dev = grt->dst.dev;
1931                                 idev = grt->rt6i_idev;
1932                                 dev_hold(dev);
1933                                 in6_dev_hold(grt->rt6i_idev);
1934                         }
1935                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1936                                 err = 0;
1937                         ip6_rt_put(grt);
1938
1939                         if (err)
1940                                 goto out;
1941                 }
1942                 err = -EINVAL;
1943                 if (!dev || (dev->flags & IFF_LOOPBACK))
1944                         goto out;
1945         }
1946
1947         err = -ENODEV;
1948         if (!dev)
1949                 goto out;
1950
1951         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1952                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1953                         err = -EINVAL;
1954                         goto out;
1955                 }
1956                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1957                 rt->rt6i_prefsrc.plen = 128;
1958         } else
1959                 rt->rt6i_prefsrc.plen = 0;
1960
1961         rt->rt6i_flags = cfg->fc_flags;
1962
1963 install_route:
1964         rt->dst.dev = dev;
1965         rt->rt6i_idev = idev;
1966         rt->rt6i_table = table;
1967
1968         cfg->fc_nlinfo.nl_net = dev_net(dev);
1969
1970         return rt;
1971 out:
1972         if (dev)
1973                 dev_put(dev);
1974         if (idev)
1975                 in6_dev_put(idev);
1976         if (rt)
1977                 dst_free(&rt->dst);
1978
1979         return ERR_PTR(err);
1980 }
1981
1982 int ip6_route_add(struct fib6_config *cfg)
1983 {
1984         struct mx6_config mxc = { .mx = NULL, };
1985         struct rt6_info *rt;
1986         int err;
1987
1988         rt = ip6_route_info_create(cfg);
1989         if (IS_ERR(rt)) {
1990                 err = PTR_ERR(rt);
1991                 rt = NULL;
1992                 goto out;
1993         }
1994
1995         err = ip6_convert_metrics(&mxc, cfg);
1996         if (err)
1997                 goto out;
1998
1999         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2000
2001         kfree(mxc.mx);
2002
2003         return err;
2004 out:
2005         if (rt)
2006                 dst_free(&rt->dst);
2007
2008         return err;
2009 }
2010
2011 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2012 {
2013         int err;
2014         struct fib6_table *table;
2015         struct net *net = dev_net(rt->dst.dev);
2016
2017         if (rt == net->ipv6.ip6_null_entry ||
2018             rt->dst.flags & DST_NOCACHE) {
2019                 err = -ENOENT;
2020                 goto out;
2021         }
2022
2023         table = rt->rt6i_table;
2024         write_lock_bh(&table->tb6_lock);
2025         err = fib6_del(rt, info);
2026         write_unlock_bh(&table->tb6_lock);
2027
2028 out:
2029         ip6_rt_put(rt);
2030         return err;
2031 }
2032
2033 int ip6_del_rt(struct rt6_info *rt)
2034 {
2035         struct nl_info info = {
2036                 .nl_net = dev_net(rt->dst.dev),
2037         };
2038         return __ip6_del_rt(rt, &info);
2039 }
2040
2041 static int ip6_route_del(struct fib6_config *cfg)
2042 {
2043         struct fib6_table *table;
2044         struct fib6_node *fn;
2045         struct rt6_info *rt;
2046         int err = -ESRCH;
2047
2048         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2049         if (!table)
2050                 return err;
2051
2052         read_lock_bh(&table->tb6_lock);
2053
2054         fn = fib6_locate(&table->tb6_root,
2055                          &cfg->fc_dst, cfg->fc_dst_len,
2056                          &cfg->fc_src, cfg->fc_src_len);
2057
2058         if (fn) {
2059                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2060                         if ((rt->rt6i_flags & RTF_CACHE) &&
2061                             !(cfg->fc_flags & RTF_CACHE))
2062                                 continue;
2063                         if (cfg->fc_ifindex &&
2064                             (!rt->dst.dev ||
2065                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2066                                 continue;
2067                         if (cfg->fc_flags & RTF_GATEWAY &&
2068                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2069                                 continue;
2070                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2071                                 continue;
2072                         dst_hold(&rt->dst);
2073                         read_unlock_bh(&table->tb6_lock);
2074
2075                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2076                 }
2077         }
2078         read_unlock_bh(&table->tb6_lock);
2079
2080         return err;
2081 }
2082
2083 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2084 {
2085         struct net *net = dev_net(skb->dev);
2086         struct netevent_redirect netevent;
2087         struct rt6_info *rt, *nrt = NULL;
2088         struct ndisc_options ndopts;
2089         struct inet6_dev *in6_dev;
2090         struct neighbour *neigh;
2091         struct rd_msg *msg;
2092         int optlen, on_link;
2093         u8 *lladdr;
2094
2095         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2096         optlen -= sizeof(*msg);
2097
2098         if (optlen < 0) {
2099                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2100                 return;
2101         }
2102
2103         msg = (struct rd_msg *)icmp6_hdr(skb);
2104
2105         if (ipv6_addr_is_multicast(&msg->dest)) {
2106                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2107                 return;
2108         }
2109
2110         on_link = 0;
2111         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2112                 on_link = 1;
2113         } else if (ipv6_addr_type(&msg->target) !=
2114                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2115                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2116                 return;
2117         }
2118
2119         in6_dev = __in6_dev_get(skb->dev);
2120         if (!in6_dev)
2121                 return;
2122         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2123                 return;
2124
2125         /* RFC2461 8.1:
2126          *      The IP source address of the Redirect MUST be the same as the current
2127          *      first-hop router for the specified ICMP Destination Address.
2128          */
2129
2130         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2131                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2132                 return;
2133         }
2134
2135         lladdr = NULL;
2136         if (ndopts.nd_opts_tgt_lladdr) {
2137                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2138                                              skb->dev);
2139                 if (!lladdr) {
2140                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2141                         return;
2142                 }
2143         }
2144
2145         rt = (struct rt6_info *) dst;
2146         if (rt == net->ipv6.ip6_null_entry) {
2147                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2148                 return;
2149         }
2150
2151         /* Redirect received -> path was valid.
2152          * Look, redirects are sent only in response to data packets,
2153          * so that this nexthop apparently is reachable. --ANK
2154          */
2155         dst_confirm(&rt->dst);
2156
2157         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2158         if (!neigh)
2159                 return;
2160
2161         /*
2162          *      We have finally decided to accept it.
2163          */
2164
2165         neigh_update(neigh, lladdr, NUD_STALE,
2166                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2167                      NEIGH_UPDATE_F_OVERRIDE|
2168                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2169                                      NEIGH_UPDATE_F_ISROUTER))
2170                      );
2171
2172         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2173         if (!nrt)
2174                 goto out;
2175
2176         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2177         if (on_link)
2178                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2179
2180         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2181
2182         if (ip6_ins_rt(nrt))
2183                 goto out;
2184
2185         netevent.old = &rt->dst;
2186         netevent.new = &nrt->dst;
2187         netevent.daddr = &msg->dest;
2188         netevent.neigh = neigh;
2189         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2190
2191         if (rt->rt6i_flags & RTF_CACHE) {
2192                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2193                 ip6_del_rt(rt);
2194         }
2195
2196 out:
2197         neigh_release(neigh);
2198 }
2199
2200 /*
2201  *      Misc support functions
2202  */
2203
2204 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2205 {
2206         BUG_ON(from->dst.from);
2207
2208         rt->rt6i_flags &= ~RTF_EXPIRES;
2209         dst_hold(&from->dst);
2210         rt->dst.from = &from->dst;
2211         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2212 }
2213
2214 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2215 {
2216         rt->dst.input = ort->dst.input;
2217         rt->dst.output = ort->dst.output;
2218         rt->rt6i_dst = ort->rt6i_dst;
2219         rt->dst.error = ort->dst.error;
2220         rt->rt6i_idev = ort->rt6i_idev;
2221         if (rt->rt6i_idev)
2222                 in6_dev_hold(rt->rt6i_idev);
2223         rt->dst.lastuse = jiffies;
2224         rt->rt6i_gateway = ort->rt6i_gateway;
2225         rt->rt6i_flags = ort->rt6i_flags;
2226         rt6_set_from(rt, ort);
2227         rt->rt6i_metric = ort->rt6i_metric;
2228 #ifdef CONFIG_IPV6_SUBTREES
2229         rt->rt6i_src = ort->rt6i_src;
2230 #endif
2231         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2232         rt->rt6i_table = ort->rt6i_table;
2233         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2234 }
2235
2236 #ifdef CONFIG_IPV6_ROUTE_INFO
2237 static struct rt6_info *rt6_get_route_info(struct net *net,
2238                                            const struct in6_addr *prefix, int prefixlen,
2239                                            const struct in6_addr *gwaddr, int ifindex)
2240 {
2241         struct fib6_node *fn;
2242         struct rt6_info *rt = NULL;
2243         struct fib6_table *table;
2244
2245         table = fib6_get_table(net, RT6_TABLE_INFO);
2246         if (!table)
2247                 return NULL;
2248
2249         read_lock_bh(&table->tb6_lock);
2250         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2251         if (!fn)
2252                 goto out;
2253
2254         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2255                 if (rt->dst.dev->ifindex != ifindex)
2256                         continue;
2257                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2258                         continue;
2259                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2260                         continue;
2261                 dst_hold(&rt->dst);
2262                 break;
2263         }
2264 out:
2265         read_unlock_bh(&table->tb6_lock);
2266         return rt;
2267 }
2268
2269 static struct rt6_info *rt6_add_route_info(struct net *net,
2270                                            const struct in6_addr *prefix, int prefixlen,
2271                                            const struct in6_addr *gwaddr, int ifindex,
2272                                            unsigned int pref)
2273 {
2274         struct fib6_config cfg = {
2275                 .fc_metric      = IP6_RT_PRIO_USER,
2276                 .fc_ifindex     = ifindex,
2277                 .fc_dst_len     = prefixlen,
2278                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2279                                   RTF_UP | RTF_PREF(pref),
2280                 .fc_nlinfo.portid = 0,
2281                 .fc_nlinfo.nlh = NULL,
2282                 .fc_nlinfo.nl_net = net,
2283         };
2284
2285         cfg.fc_table = l3mdev_fib_table_by_index(net, ifindex) ? : RT6_TABLE_INFO;
2286         cfg.fc_dst = *prefix;
2287         cfg.fc_gateway = *gwaddr;
2288
2289         /* We should treat it as a default route if prefix length is 0. */
2290         if (!prefixlen)
2291                 cfg.fc_flags |= RTF_DEFAULT;
2292
2293         ip6_route_add(&cfg);
2294
2295         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2296 }
2297 #endif
2298
2299 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2300 {
2301         struct rt6_info *rt;
2302         struct fib6_table *table;
2303
2304         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2305         if (!table)
2306                 return NULL;
2307
2308         read_lock_bh(&table->tb6_lock);
2309         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2310                 if (dev == rt->dst.dev &&
2311                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2312                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2313                         break;
2314         }
2315         if (rt)
2316                 dst_hold(&rt->dst);
2317         read_unlock_bh(&table->tb6_lock);
2318         return rt;
2319 }
2320
2321 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2322                                      struct net_device *dev,
2323                                      unsigned int pref)
2324 {
2325         struct fib6_config cfg = {
2326                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2327                 .fc_metric      = IP6_RT_PRIO_USER,
2328                 .fc_ifindex     = dev->ifindex,
2329                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2330                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2331                 .fc_nlinfo.portid = 0,
2332                 .fc_nlinfo.nlh = NULL,
2333                 .fc_nlinfo.nl_net = dev_net(dev),
2334         };
2335
2336         cfg.fc_gateway = *gwaddr;
2337
2338         ip6_route_add(&cfg);
2339
2340         return rt6_get_dflt_router(gwaddr, dev);
2341 }
2342
2343 void rt6_purge_dflt_routers(struct net *net)
2344 {
2345         struct rt6_info *rt;
2346         struct fib6_table *table;
2347
2348         /* NOTE: Keep consistent with rt6_get_dflt_router */
2349         table = fib6_get_table(net, RT6_TABLE_DFLT);
2350         if (!table)
2351                 return;
2352
2353 restart:
2354         read_lock_bh(&table->tb6_lock);
2355         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2356                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2357                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2358                         dst_hold(&rt->dst);
2359                         read_unlock_bh(&table->tb6_lock);
2360                         ip6_del_rt(rt);
2361                         goto restart;
2362                 }
2363         }
2364         read_unlock_bh(&table->tb6_lock);
2365 }
2366
2367 static void rtmsg_to_fib6_config(struct net *net,
2368                                  struct in6_rtmsg *rtmsg,
2369                                  struct fib6_config *cfg)
2370 {
2371         memset(cfg, 0, sizeof(*cfg));
2372
2373         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2374                          : RT6_TABLE_MAIN;
2375         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2376         cfg->fc_metric = rtmsg->rtmsg_metric;
2377         cfg->fc_expires = rtmsg->rtmsg_info;
2378         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2379         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2380         cfg->fc_flags = rtmsg->rtmsg_flags;
2381
2382         cfg->fc_nlinfo.nl_net = net;
2383
2384         cfg->fc_dst = rtmsg->rtmsg_dst;
2385         cfg->fc_src = rtmsg->rtmsg_src;
2386         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2387 }
2388
2389 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2390 {
2391         struct fib6_config cfg;
2392         struct in6_rtmsg rtmsg;
2393         int err;
2394
2395         switch (cmd) {
2396         case SIOCADDRT:         /* Add a route */
2397         case SIOCDELRT:         /* Delete a route */
2398                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2399                         return -EPERM;
2400                 err = copy_from_user(&rtmsg, arg,
2401                                      sizeof(struct in6_rtmsg));
2402                 if (err)
2403                         return -EFAULT;
2404
2405                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2406
2407                 rtnl_lock();
2408                 switch (cmd) {
2409                 case SIOCADDRT:
2410                         err = ip6_route_add(&cfg);
2411                         break;
2412                 case SIOCDELRT:
2413                         err = ip6_route_del(&cfg);
2414                         break;
2415                 default:
2416                         err = -EINVAL;
2417                 }
2418                 rtnl_unlock();
2419
2420                 return err;
2421         }
2422
2423         return -EINVAL;
2424 }
2425
2426 /*
2427  *      Drop the packet on the floor
2428  */
2429
2430 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2431 {
2432         int type;
2433         struct dst_entry *dst = skb_dst(skb);
2434         switch (ipstats_mib_noroutes) {
2435         case IPSTATS_MIB_INNOROUTES:
2436                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2437                 if (type == IPV6_ADDR_ANY) {
2438                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2439                                       IPSTATS_MIB_INADDRERRORS);
2440                         break;
2441                 }
2442                 /* FALLTHROUGH */
2443         case IPSTATS_MIB_OUTNOROUTES:
2444                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2445                               ipstats_mib_noroutes);
2446                 break;
2447         }
2448         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2449         kfree_skb(skb);
2450         return 0;
2451 }
2452
2453 static int ip6_pkt_discard(struct sk_buff *skb)
2454 {
2455         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2456 }
2457
2458 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2459 {
2460         skb->dev = skb_dst(skb)->dev;
2461         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2462 }
2463
2464 static int ip6_pkt_prohibit(struct sk_buff *skb)
2465 {
2466         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2467 }
2468
2469 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2470 {
2471         skb->dev = skb_dst(skb)->dev;
2472         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2473 }
2474
2475 /*
2476  *      Allocate a dst for local (unicast / anycast) address.
2477  */
2478
2479 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2480                                     const struct in6_addr *addr,
2481                                     bool anycast)
2482 {
2483         u32 tb_id;
2484         struct net *net = dev_net(idev->dev);
2485         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2486                                             DST_NOCOUNT);
2487         if (!rt)
2488                 return ERR_PTR(-ENOMEM);
2489
2490         in6_dev_hold(idev);
2491
2492         rt->dst.flags |= DST_HOST;
2493         rt->dst.input = ip6_input;
2494         rt->dst.output = ip6_output;
2495         rt->rt6i_idev = idev;
2496
2497         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2498         if (anycast)
2499                 rt->rt6i_flags |= RTF_ANYCAST;
2500         else
2501                 rt->rt6i_flags |= RTF_LOCAL;
2502
2503         rt->rt6i_gateway  = *addr;
2504         rt->rt6i_dst.addr = *addr;
2505         rt->rt6i_dst.plen = 128;
2506         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2507         rt->rt6i_table = fib6_get_table(net, tb_id);
2508         rt->dst.flags |= DST_NOCACHE;
2509
2510         atomic_set(&rt->dst.__refcnt, 1);
2511
2512         return rt;
2513 }
2514
2515 int ip6_route_get_saddr(struct net *net,
2516                         struct rt6_info *rt,
2517                         const struct in6_addr *daddr,
2518                         unsigned int prefs,
2519                         struct in6_addr *saddr)
2520 {
2521         struct inet6_dev *idev =
2522                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2523         int err = 0;
2524         if (rt && rt->rt6i_prefsrc.plen)
2525                 *saddr = rt->rt6i_prefsrc.addr;
2526         else
2527                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2528                                          daddr, prefs, saddr);
2529         return err;
2530 }
2531
2532 /* remove deleted ip from prefsrc entries */
2533 struct arg_dev_net_ip {
2534         struct net_device *dev;
2535         struct net *net;
2536         struct in6_addr *addr;
2537 };
2538
2539 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2540 {
2541         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2542         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2543         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2544
2545         if (((void *)rt->dst.dev == dev || !dev) &&
2546             rt != net->ipv6.ip6_null_entry &&
2547             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2548                 /* remove prefsrc entry */
2549                 rt->rt6i_prefsrc.plen = 0;
2550         }
2551         return 0;
2552 }
2553
2554 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2555 {
2556         struct net *net = dev_net(ifp->idev->dev);
2557         struct arg_dev_net_ip adni = {
2558                 .dev = ifp->idev->dev,
2559                 .net = net,
2560                 .addr = &ifp->addr,
2561         };
2562         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2563 }
2564
2565 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2566 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2567
2568 /* Remove routers and update dst entries when gateway turn into host. */
2569 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2570 {
2571         struct in6_addr *gateway = (struct in6_addr *)arg;
2572
2573         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2574              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2575              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2576                 return -1;
2577         }
2578         return 0;
2579 }
2580
2581 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2582 {
2583         fib6_clean_all(net, fib6_clean_tohost, gateway);
2584 }
2585
2586 struct arg_dev_net {
2587         struct net_device *dev;
2588         struct net *net;
2589 };
2590
2591 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2592 {
2593         const struct arg_dev_net *adn = arg;
2594         const struct net_device *dev = adn->dev;
2595
2596         if ((rt->dst.dev == dev || !dev) &&
2597             rt != adn->net->ipv6.ip6_null_entry)
2598                 return -1;
2599
2600         return 0;
2601 }
2602
2603 void rt6_ifdown(struct net *net, struct net_device *dev)
2604 {
2605         struct arg_dev_net adn = {
2606                 .dev = dev,
2607                 .net = net,
2608         };
2609
2610         fib6_clean_all(net, fib6_ifdown, &adn);
2611         icmp6_clean_all(fib6_ifdown, &adn);
2612         rt6_uncached_list_flush_dev(net, dev);
2613 }
2614
2615 struct rt6_mtu_change_arg {
2616         struct net_device *dev;
2617         unsigned int mtu;
2618 };
2619
2620 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2621 {
2622         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2623         struct inet6_dev *idev;
2624
2625         /* In IPv6 pmtu discovery is not optional,
2626            so that RTAX_MTU lock cannot disable it.
2627            We still use this lock to block changes
2628            caused by addrconf/ndisc.
2629         */
2630
2631         idev = __in6_dev_get(arg->dev);
2632         if (!idev)
2633                 return 0;
2634
2635         /* For administrative MTU increase, there is no way to discover
2636            IPv6 PMTU increase, so PMTU increase should be updated here.
2637            Since RFC 1981 doesn't include administrative MTU increase
2638            update PMTU increase is a MUST. (i.e. jumbo frame)
2639          */
2640         /*
2641            If new MTU is less than route PMTU, this new MTU will be the
2642            lowest MTU in the path, update the route PMTU to reflect PMTU
2643            decreases; if new MTU is greater than route PMTU, and the
2644            old MTU is the lowest MTU in the path, update the route PMTU
2645            to reflect the increase. In this case if the other nodes' MTU
2646            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2647            PMTU discouvery.
2648          */
2649         if (rt->dst.dev == arg->dev &&
2650             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2651                 if (rt->rt6i_flags & RTF_CACHE) {
2652                         /* For RTF_CACHE with rt6i_pmtu == 0
2653                          * (i.e. a redirected route),
2654                          * the metrics of its rt->dst.from has already
2655                          * been updated.
2656                          */
2657                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2658                                 rt->rt6i_pmtu = arg->mtu;
2659                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2660                            (dst_mtu(&rt->dst) < arg->mtu &&
2661                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2662                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2663                 }
2664         }
2665         return 0;
2666 }
2667
2668 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2669 {
2670         struct rt6_mtu_change_arg arg = {
2671                 .dev = dev,
2672                 .mtu = mtu,
2673         };
2674
2675         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2676 }
2677
2678 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2679         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2680         [RTA_OIF]               = { .type = NLA_U32 },
2681         [RTA_IIF]               = { .type = NLA_U32 },
2682         [RTA_PRIORITY]          = { .type = NLA_U32 },
2683         [RTA_METRICS]           = { .type = NLA_NESTED },
2684         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2685         [RTA_PREF]              = { .type = NLA_U8 },
2686         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2687         [RTA_ENCAP]             = { .type = NLA_NESTED },
2688 };
2689
2690 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2691                               struct fib6_config *cfg)
2692 {
2693         struct rtmsg *rtm;
2694         struct nlattr *tb[RTA_MAX+1];
2695         unsigned int pref;
2696         int err;
2697
2698         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2699         if (err < 0)
2700                 goto errout;
2701
2702         err = -EINVAL;
2703         rtm = nlmsg_data(nlh);
2704         memset(cfg, 0, sizeof(*cfg));
2705
2706         cfg->fc_table = rtm->rtm_table;
2707         cfg->fc_dst_len = rtm->rtm_dst_len;
2708         cfg->fc_src_len = rtm->rtm_src_len;
2709         cfg->fc_flags = RTF_UP;
2710         cfg->fc_protocol = rtm->rtm_protocol;
2711         cfg->fc_type = rtm->rtm_type;
2712
2713         if (rtm->rtm_type == RTN_UNREACHABLE ||
2714             rtm->rtm_type == RTN_BLACKHOLE ||
2715             rtm->rtm_type == RTN_PROHIBIT ||
2716             rtm->rtm_type == RTN_THROW)
2717                 cfg->fc_flags |= RTF_REJECT;
2718
2719         if (rtm->rtm_type == RTN_LOCAL)
2720                 cfg->fc_flags |= RTF_LOCAL;
2721
2722         if (rtm->rtm_flags & RTM_F_CLONED)
2723                 cfg->fc_flags |= RTF_CACHE;
2724
2725         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2726         cfg->fc_nlinfo.nlh = nlh;
2727         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2728
2729         if (tb[RTA_GATEWAY]) {
2730                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2731                 cfg->fc_flags |= RTF_GATEWAY;
2732         }
2733
2734         if (tb[RTA_DST]) {
2735                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2736
2737                 if (nla_len(tb[RTA_DST]) < plen)
2738                         goto errout;
2739
2740                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2741         }
2742
2743         if (tb[RTA_SRC]) {
2744                 int plen = (rtm->rtm_src_len + 7) >> 3;
2745
2746                 if (nla_len(tb[RTA_SRC]) < plen)
2747                         goto errout;
2748
2749                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2750         }
2751
2752         if (tb[RTA_PREFSRC])
2753                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2754
2755         if (tb[RTA_OIF])
2756                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2757
2758         if (tb[RTA_PRIORITY])
2759                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2760
2761         if (tb[RTA_METRICS]) {
2762                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2763                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2764         }
2765
2766         if (tb[RTA_TABLE])
2767                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2768
2769         if (tb[RTA_MULTIPATH]) {
2770                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2771                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2772         }
2773
2774         if (tb[RTA_PREF]) {
2775                 pref = nla_get_u8(tb[RTA_PREF]);
2776                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2777                     pref != ICMPV6_ROUTER_PREF_HIGH)
2778                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2779                 cfg->fc_flags |= RTF_PREF(pref);
2780         }
2781
2782         if (tb[RTA_ENCAP])
2783                 cfg->fc_encap = tb[RTA_ENCAP];
2784
2785         if (tb[RTA_ENCAP_TYPE])
2786                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2787
2788         err = 0;
2789 errout:
2790         return err;
2791 }
2792
2793 struct rt6_nh {
2794         struct rt6_info *rt6_info;
2795         struct fib6_config r_cfg;
2796         struct mx6_config mxc;
2797         struct list_head next;
2798 };
2799
2800 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2801 {
2802         struct rt6_nh *nh;
2803
2804         list_for_each_entry(nh, rt6_nh_list, next) {
2805                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2806                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2807                         nh->r_cfg.fc_ifindex);
2808         }
2809 }
2810
2811 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2812                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2813 {
2814         struct rt6_nh *nh;
2815         struct rt6_info *rtnh;
2816         int err = -EEXIST;
2817
2818         list_for_each_entry(nh, rt6_nh_list, next) {
2819                 /* check if rt6_info already exists */
2820                 rtnh = nh->rt6_info;
2821
2822                 if (rtnh->dst.dev == rt->dst.dev &&
2823                     rtnh->rt6i_idev == rt->rt6i_idev &&
2824                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2825                                     &rt->rt6i_gateway))
2826                         return err;
2827         }
2828
2829         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2830         if (!nh)
2831                 return -ENOMEM;
2832         nh->rt6_info = rt;
2833         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2834         if (err) {
2835                 kfree(nh);
2836                 return err;
2837         }
2838         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2839         list_add_tail(&nh->next, rt6_nh_list);
2840
2841         return 0;
2842 }
2843
2844 static int ip6_route_multipath_add(struct fib6_config *cfg)
2845 {
2846         struct fib6_config r_cfg;
2847         struct rtnexthop *rtnh;
2848         struct rt6_info *rt;
2849         struct rt6_nh *err_nh;
2850         struct rt6_nh *nh, *nh_safe;
2851         int remaining;
2852         int attrlen;
2853         int err = 1;
2854         int nhn = 0;
2855         int replace = (cfg->fc_nlinfo.nlh &&
2856                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2857         LIST_HEAD(rt6_nh_list);
2858
2859         remaining = cfg->fc_mp_len;
2860         rtnh = (struct rtnexthop *)cfg->fc_mp;
2861
2862         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2863          * rt6_info structs per nexthop
2864          */
2865         while (rtnh_ok(rtnh, remaining)) {
2866                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2867                 if (rtnh->rtnh_ifindex)
2868                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2869
2870                 attrlen = rtnh_attrlen(rtnh);
2871                 if (attrlen > 0) {
2872                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2873
2874                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2875                         if (nla) {
2876                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2877                                 r_cfg.fc_flags |= RTF_GATEWAY;
2878                         }
2879                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2880                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2881                         if (nla)
2882                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2883                 }
2884
2885                 rt = ip6_route_info_create(&r_cfg);
2886                 if (IS_ERR(rt)) {
2887                         err = PTR_ERR(rt);
2888                         rt = NULL;
2889                         goto cleanup;
2890                 }
2891
2892                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2893                 if (err) {
2894                         dst_free(&rt->dst);
2895                         goto cleanup;
2896                 }
2897
2898                 rtnh = rtnh_next(rtnh, &remaining);
2899         }
2900
2901         err_nh = NULL;
2902         list_for_each_entry(nh, &rt6_nh_list, next) {
2903                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2904                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2905                 nh->rt6_info = NULL;
2906                 if (err) {
2907                         if (replace && nhn)
2908                                 ip6_print_replace_route_err(&rt6_nh_list);
2909                         err_nh = nh;
2910                         goto add_errout;
2911                 }
2912
2913                 /* Because each route is added like a single route we remove
2914                  * these flags after the first nexthop: if there is a collision,
2915                  * we have already failed to add the first nexthop:
2916                  * fib6_add_rt2node() has rejected it; when replacing, old
2917                  * nexthops have been replaced by first new, the rest should
2918                  * be added to it.
2919                  */
2920                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2921                                                      NLM_F_REPLACE);
2922                 nhn++;
2923         }
2924
2925         goto cleanup;
2926
2927 add_errout:
2928         /* Delete routes that were already added */
2929         list_for_each_entry(nh, &rt6_nh_list, next) {
2930                 if (err_nh == nh)
2931                         break;
2932                 ip6_route_del(&nh->r_cfg);
2933         }
2934
2935 cleanup:
2936         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2937                 if (nh->rt6_info)
2938                         dst_free(&nh->rt6_info->dst);
2939                 kfree(nh->mxc.mx);
2940                 list_del(&nh->next);
2941                 kfree(nh);
2942         }
2943
2944         return err;
2945 }
2946
2947 static int ip6_route_multipath_del(struct fib6_config *cfg)
2948 {
2949         struct fib6_config r_cfg;
2950         struct rtnexthop *rtnh;
2951         int remaining;
2952         int attrlen;
2953         int err = 1, last_err = 0;
2954
2955         remaining = cfg->fc_mp_len;
2956         rtnh = (struct rtnexthop *)cfg->fc_mp;
2957
2958         /* Parse a Multipath Entry */
2959         while (rtnh_ok(rtnh, remaining)) {
2960                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2961                 if (rtnh->rtnh_ifindex)
2962                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2963
2964                 attrlen = rtnh_attrlen(rtnh);
2965                 if (attrlen > 0) {
2966                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2967
2968                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2969                         if (nla) {
2970                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2971                                 r_cfg.fc_flags |= RTF_GATEWAY;
2972                         }
2973                 }
2974                 err = ip6_route_del(&r_cfg);
2975                 if (err)
2976                         last_err = err;
2977
2978                 rtnh = rtnh_next(rtnh, &remaining);
2979         }
2980
2981         return last_err;
2982 }
2983
2984 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2985 {
2986         struct fib6_config cfg;
2987         int err;
2988
2989         err = rtm_to_fib6_config(skb, nlh, &cfg);
2990         if (err < 0)
2991                 return err;
2992
2993         if (cfg.fc_mp)
2994                 return ip6_route_multipath_del(&cfg);
2995         else
2996                 return ip6_route_del(&cfg);
2997 }
2998
2999 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3000 {
3001         struct fib6_config cfg;
3002         int err;
3003
3004         err = rtm_to_fib6_config(skb, nlh, &cfg);
3005         if (err < 0)
3006                 return err;
3007
3008         if (cfg.fc_mp)
3009                 return ip6_route_multipath_add(&cfg);
3010         else
3011                 return ip6_route_add(&cfg);
3012 }
3013
3014 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3015 {
3016         return NLMSG_ALIGN(sizeof(struct rtmsg))
3017                + nla_total_size(16) /* RTA_SRC */
3018                + nla_total_size(16) /* RTA_DST */
3019                + nla_total_size(16) /* RTA_GATEWAY */
3020                + nla_total_size(16) /* RTA_PREFSRC */
3021                + nla_total_size(4) /* RTA_TABLE */
3022                + nla_total_size(4) /* RTA_IIF */
3023                + nla_total_size(4) /* RTA_OIF */
3024                + nla_total_size(4) /* RTA_PRIORITY */
3025                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3026                + nla_total_size(sizeof(struct rta_cacheinfo))
3027                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3028                + nla_total_size(1) /* RTA_PREF */
3029                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3030 }
3031
3032 static int rt6_fill_node(struct net *net,
3033                          struct sk_buff *skb, struct rt6_info *rt,
3034                          struct in6_addr *dst, struct in6_addr *src,
3035                          int iif, int type, u32 portid, u32 seq,
3036                          int prefix, int nowait, unsigned int flags)
3037 {
3038         u32 metrics[RTAX_MAX];
3039         struct rtmsg *rtm;
3040         struct nlmsghdr *nlh;
3041         long expires;
3042         u32 table;
3043
3044         if (prefix) {   /* user wants prefix routes only */
3045                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3046                         /* success since this is not a prefix route */
3047                         return 1;
3048                 }
3049         }
3050
3051         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3052         if (!nlh)
3053                 return -EMSGSIZE;
3054
3055         rtm = nlmsg_data(nlh);
3056         rtm->rtm_family = AF_INET6;
3057         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3058         rtm->rtm_src_len = rt->rt6i_src.plen;
3059         rtm->rtm_tos = 0;
3060         if (rt->rt6i_table)
3061                 table = rt->rt6i_table->tb6_id;
3062         else
3063                 table = RT6_TABLE_UNSPEC;
3064         rtm->rtm_table = table;
3065         if (nla_put_u32(skb, RTA_TABLE, table))
3066                 goto nla_put_failure;
3067         if (rt->rt6i_flags & RTF_REJECT) {
3068                 switch (rt->dst.error) {
3069                 case -EINVAL:
3070                         rtm->rtm_type = RTN_BLACKHOLE;
3071                         break;
3072                 case -EACCES:
3073                         rtm->rtm_type = RTN_PROHIBIT;
3074                         break;
3075                 case -EAGAIN:
3076                         rtm->rtm_type = RTN_THROW;
3077                         break;
3078                 default:
3079                         rtm->rtm_type = RTN_UNREACHABLE;
3080                         break;
3081                 }
3082         }
3083         else if (rt->rt6i_flags & RTF_LOCAL)
3084                 rtm->rtm_type = RTN_LOCAL;
3085         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3086                 rtm->rtm_type = RTN_LOCAL;
3087         else
3088                 rtm->rtm_type = RTN_UNICAST;
3089         rtm->rtm_flags = 0;
3090         if (!netif_carrier_ok(rt->dst.dev)) {
3091                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3092                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3093                         rtm->rtm_flags |= RTNH_F_DEAD;
3094         }
3095         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3096         rtm->rtm_protocol = rt->rt6i_protocol;
3097         if (rt->rt6i_flags & RTF_DYNAMIC)
3098                 rtm->rtm_protocol = RTPROT_REDIRECT;
3099         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3100                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3101                         rtm->rtm_protocol = RTPROT_RA;
3102                 else
3103                         rtm->rtm_protocol = RTPROT_KERNEL;
3104         }
3105
3106         if (rt->rt6i_flags & RTF_CACHE)
3107                 rtm->rtm_flags |= RTM_F_CLONED;
3108
3109         if (dst) {
3110                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3111                         goto nla_put_failure;
3112                 rtm->rtm_dst_len = 128;
3113         } else if (rtm->rtm_dst_len)
3114                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3115                         goto nla_put_failure;
3116 #ifdef CONFIG_IPV6_SUBTREES
3117         if (src) {
3118                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3119                         goto nla_put_failure;
3120                 rtm->rtm_src_len = 128;
3121         } else if (rtm->rtm_src_len &&
3122                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3123                 goto nla_put_failure;
3124 #endif
3125         if (iif) {
3126 #ifdef CONFIG_IPV6_MROUTE
3127                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3128                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3129                         if (err <= 0) {
3130                                 if (!nowait) {
3131                                         if (err == 0)
3132                                                 return 0;
3133                                         goto nla_put_failure;
3134                                 } else {
3135                                         if (err == -EMSGSIZE)
3136                                                 goto nla_put_failure;
3137                                 }
3138                         }
3139                 } else
3140 #endif
3141                         if (nla_put_u32(skb, RTA_IIF, iif))
3142                                 goto nla_put_failure;
3143         } else if (dst) {
3144                 struct in6_addr saddr_buf;
3145                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3146                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3147                         goto nla_put_failure;
3148         }
3149
3150         if (rt->rt6i_prefsrc.plen) {
3151                 struct in6_addr saddr_buf;
3152                 saddr_buf = rt->rt6i_prefsrc.addr;
3153                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3154                         goto nla_put_failure;
3155         }
3156
3157         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3158         if (rt->rt6i_pmtu)
3159                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3160         if (rtnetlink_put_metrics(skb, metrics) < 0)
3161                 goto nla_put_failure;
3162
3163         if (rt->rt6i_flags & RTF_GATEWAY) {
3164                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3165                         goto nla_put_failure;
3166         }
3167
3168         if (rt->dst.dev &&
3169             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3170                 goto nla_put_failure;
3171         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3172                 goto nla_put_failure;
3173
3174         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3175
3176         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3177                 goto nla_put_failure;
3178
3179         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3180                 goto nla_put_failure;
3181
3182         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3183
3184         nlmsg_end(skb, nlh);
3185         return 0;
3186
3187 nla_put_failure:
3188         nlmsg_cancel(skb, nlh);
3189         return -EMSGSIZE;
3190 }
3191
3192 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3193 {
3194         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3195         int prefix;
3196
3197         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3198                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3199                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3200         } else
3201                 prefix = 0;
3202
3203         return rt6_fill_node(arg->net,
3204                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3205                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3206                      prefix, 0, NLM_F_MULTI);
3207 }
3208
3209 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3210 {
3211         struct net *net = sock_net(in_skb->sk);
3212         struct nlattr *tb[RTA_MAX+1];
3213         struct rt6_info *rt;
3214         struct sk_buff *skb;
3215         struct rtmsg *rtm;
3216         struct flowi6 fl6;
3217         int err, iif = 0, oif = 0;
3218
3219         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3220         if (err < 0)
3221                 goto errout;
3222
3223         err = -EINVAL;
3224         memset(&fl6, 0, sizeof(fl6));
3225
3226         if (tb[RTA_SRC]) {
3227                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3228                         goto errout;
3229
3230                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3231         }
3232
3233         if (tb[RTA_DST]) {
3234                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3235                         goto errout;
3236
3237                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3238         }
3239
3240         if (tb[RTA_IIF])
3241                 iif = nla_get_u32(tb[RTA_IIF]);
3242
3243         if (tb[RTA_OIF])
3244                 oif = nla_get_u32(tb[RTA_OIF]);
3245
3246         if (tb[RTA_MARK])
3247                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3248
3249         if (iif) {
3250                 struct net_device *dev;
3251                 int flags = 0;
3252
3253                 dev = __dev_get_by_index(net, iif);
3254                 if (!dev) {
3255                         err = -ENODEV;
3256                         goto errout;
3257                 }
3258
3259                 fl6.flowi6_iif = iif;
3260
3261                 if (!ipv6_addr_any(&fl6.saddr))
3262                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3263
3264                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3265                                                                flags);
3266         } else {
3267                 fl6.flowi6_oif = oif;
3268
3269                 if (netif_index_is_l3_master(net, oif)) {
3270                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3271                                            FLOWI_FLAG_SKIP_NH_OIF;
3272                 }
3273
3274                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3275         }
3276
3277         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3278         if (!skb) {
3279                 ip6_rt_put(rt);
3280                 err = -ENOBUFS;
3281                 goto errout;
3282         }
3283
3284         /* Reserve room for dummy headers, this skb can pass
3285            through good chunk of routing engine.
3286          */
3287         skb_reset_mac_header(skb);
3288         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3289
3290         skb_dst_set(skb, &rt->dst);
3291
3292         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3293                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3294                             nlh->nlmsg_seq, 0, 0, 0);
3295         if (err < 0) {
3296                 kfree_skb(skb);
3297                 goto errout;
3298         }
3299
3300         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3301 errout:
3302         return err;
3303 }
3304
3305 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3306                      unsigned int nlm_flags)
3307 {
3308         struct sk_buff *skb;
3309         struct net *net = info->nl_net;
3310         u32 seq;
3311         int err;
3312
3313         err = -ENOBUFS;
3314         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3315
3316         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3317         if (!skb)
3318                 goto errout;
3319
3320         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3321                                 event, info->portid, seq, 0, 0, nlm_flags);
3322         if (err < 0) {
3323                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3324                 WARN_ON(err == -EMSGSIZE);
3325                 kfree_skb(skb);
3326                 goto errout;
3327         }
3328         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3329                     info->nlh, gfp_any());
3330         return;
3331 errout:
3332         if (err < 0)
3333                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3334 }
3335
3336 static int ip6_route_dev_notify(struct notifier_block *this,
3337                                 unsigned long event, void *ptr)
3338 {
3339         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3340         struct net *net = dev_net(dev);
3341
3342         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3343                 net->ipv6.ip6_null_entry->dst.dev = dev;
3344                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3345 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3346                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3347                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3348                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3349                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3350 #endif
3351         }
3352
3353         return NOTIFY_OK;
3354 }
3355
3356 /*
3357  *      /proc
3358  */
3359
3360 #ifdef CONFIG_PROC_FS
3361
3362 static const struct file_operations ipv6_route_proc_fops = {
3363         .owner          = THIS_MODULE,
3364         .open           = ipv6_route_open,
3365         .read           = seq_read,
3366         .llseek         = seq_lseek,
3367         .release        = seq_release_net,
3368 };
3369
3370 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3371 {
3372         struct net *net = (struct net *)seq->private;
3373         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3374                    net->ipv6.rt6_stats->fib_nodes,
3375                    net->ipv6.rt6_stats->fib_route_nodes,
3376                    net->ipv6.rt6_stats->fib_rt_alloc,
3377                    net->ipv6.rt6_stats->fib_rt_entries,
3378                    net->ipv6.rt6_stats->fib_rt_cache,
3379                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3380                    net->ipv6.rt6_stats->fib_discarded_routes);
3381
3382         return 0;
3383 }
3384
3385 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3386 {
3387         return single_open_net(inode, file, rt6_stats_seq_show);
3388 }
3389
3390 static const struct file_operations rt6_stats_seq_fops = {
3391         .owner   = THIS_MODULE,
3392         .open    = rt6_stats_seq_open,
3393         .read    = seq_read,
3394         .llseek  = seq_lseek,
3395         .release = single_release_net,
3396 };
3397 #endif  /* CONFIG_PROC_FS */
3398
3399 #ifdef CONFIG_SYSCTL
3400
3401 static
3402 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3403                               void __user *buffer, size_t *lenp, loff_t *ppos)
3404 {
3405         struct net *net;
3406         int delay;
3407         if (!write)
3408                 return -EINVAL;
3409
3410         net = (struct net *)ctl->extra1;
3411         delay = net->ipv6.sysctl.flush_delay;
3412         proc_dointvec(ctl, write, buffer, lenp, ppos);
3413         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3414         return 0;
3415 }
3416
3417 struct ctl_table ipv6_route_table_template[] = {
3418         {
3419                 .procname       =       "flush",
3420                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3421                 .maxlen         =       sizeof(int),
3422                 .mode           =       0200,
3423                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3424         },
3425         {
3426                 .procname       =       "gc_thresh",
3427                 .data           =       &ip6_dst_ops_template.gc_thresh,
3428                 .maxlen         =       sizeof(int),
3429                 .mode           =       0644,
3430                 .proc_handler   =       proc_dointvec,
3431         },
3432         {
3433                 .procname       =       "max_size",
3434                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3435                 .maxlen         =       sizeof(int),
3436                 .mode           =       0644,
3437                 .proc_handler   =       proc_dointvec,
3438         },
3439         {
3440                 .procname       =       "gc_min_interval",
3441                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3442                 .maxlen         =       sizeof(int),
3443                 .mode           =       0644,
3444                 .proc_handler   =       proc_dointvec_jiffies,
3445         },
3446         {
3447                 .procname       =       "gc_timeout",
3448                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3449                 .maxlen         =       sizeof(int),
3450                 .mode           =       0644,
3451                 .proc_handler   =       proc_dointvec_jiffies,
3452         },
3453         {
3454                 .procname       =       "gc_interval",
3455                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3456                 .maxlen         =       sizeof(int),
3457                 .mode           =       0644,
3458                 .proc_handler   =       proc_dointvec_jiffies,
3459         },
3460         {
3461                 .procname       =       "gc_elasticity",
3462                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3463                 .maxlen         =       sizeof(int),
3464                 .mode           =       0644,
3465                 .proc_handler   =       proc_dointvec,
3466         },
3467         {
3468                 .procname       =       "mtu_expires",
3469                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3470                 .maxlen         =       sizeof(int),
3471                 .mode           =       0644,
3472                 .proc_handler   =       proc_dointvec_jiffies,
3473         },
3474         {
3475                 .procname       =       "min_adv_mss",
3476                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3477                 .maxlen         =       sizeof(int),
3478                 .mode           =       0644,
3479                 .proc_handler   =       proc_dointvec,
3480         },
3481         {
3482                 .procname       =       "gc_min_interval_ms",
3483                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3484                 .maxlen         =       sizeof(int),
3485                 .mode           =       0644,
3486                 .proc_handler   =       proc_dointvec_ms_jiffies,
3487         },
3488         { }
3489 };
3490
3491 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3492 {
3493         struct ctl_table *table;
3494
3495         table = kmemdup(ipv6_route_table_template,
3496                         sizeof(ipv6_route_table_template),
3497                         GFP_KERNEL);
3498
3499         if (table) {
3500                 table[0].data = &net->ipv6.sysctl.flush_delay;
3501                 table[0].extra1 = net;
3502                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3503                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3504                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3505                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3506                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3507                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3508                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3509                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3510                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3511
3512                 /* Don't export sysctls to unprivileged users */
3513                 if (net->user_ns != &init_user_ns)
3514                         table[0].procname = NULL;
3515         }
3516
3517         return table;
3518 }
3519 #endif
3520
3521 static int __net_init ip6_route_net_init(struct net *net)
3522 {
3523         int ret = -ENOMEM;
3524
3525         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3526                sizeof(net->ipv6.ip6_dst_ops));
3527
3528         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3529                 goto out_ip6_dst_ops;
3530
3531         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3532                                            sizeof(*net->ipv6.ip6_null_entry),
3533                                            GFP_KERNEL);
3534         if (!net->ipv6.ip6_null_entry)
3535                 goto out_ip6_dst_entries;
3536         net->ipv6.ip6_null_entry->dst.path =
3537                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3538         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3539         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3540                          ip6_template_metrics, true);
3541
3542 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3543         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3544                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3545                                                GFP_KERNEL);
3546         if (!net->ipv6.ip6_prohibit_entry)
3547                 goto out_ip6_null_entry;
3548         net->ipv6.ip6_prohibit_entry->dst.path =
3549                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3550         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3551         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3552                          ip6_template_metrics, true);
3553
3554         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3555                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3556                                                GFP_KERNEL);
3557         if (!net->ipv6.ip6_blk_hole_entry)
3558                 goto out_ip6_prohibit_entry;
3559         net->ipv6.ip6_blk_hole_entry->dst.path =
3560                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3561         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3562         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3563                          ip6_template_metrics, true);
3564 #endif
3565
3566         net->ipv6.sysctl.flush_delay = 0;
3567         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3568         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3569         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3570         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3571         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3572         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3573         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3574
3575         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3576
3577         ret = 0;
3578 out:
3579         return ret;
3580
3581 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3582 out_ip6_prohibit_entry:
3583         kfree(net->ipv6.ip6_prohibit_entry);
3584 out_ip6_null_entry:
3585         kfree(net->ipv6.ip6_null_entry);
3586 #endif
3587 out_ip6_dst_entries:
3588         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3589 out_ip6_dst_ops:
3590         goto out;
3591 }
3592
3593 static void __net_exit ip6_route_net_exit(struct net *net)
3594 {
3595         kfree(net->ipv6.ip6_null_entry);
3596 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3597         kfree(net->ipv6.ip6_prohibit_entry);
3598         kfree(net->ipv6.ip6_blk_hole_entry);
3599 #endif
3600         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3601 }
3602
3603 static int __net_init ip6_route_net_init_late(struct net *net)
3604 {
3605 #ifdef CONFIG_PROC_FS
3606         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3607         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3608 #endif
3609         return 0;
3610 }
3611
3612 static void __net_exit ip6_route_net_exit_late(struct net *net)
3613 {
3614 #ifdef CONFIG_PROC_FS
3615         remove_proc_entry("ipv6_route", net->proc_net);
3616         remove_proc_entry("rt6_stats", net->proc_net);
3617 #endif
3618 }
3619
3620 static struct pernet_operations ip6_route_net_ops = {
3621         .init = ip6_route_net_init,
3622         .exit = ip6_route_net_exit,
3623 };
3624
3625 static int __net_init ipv6_inetpeer_init(struct net *net)
3626 {
3627         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3628
3629         if (!bp)
3630                 return -ENOMEM;
3631         inet_peer_base_init(bp);
3632         net->ipv6.peers = bp;
3633         return 0;
3634 }
3635
3636 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3637 {
3638         struct inet_peer_base *bp = net->ipv6.peers;
3639
3640         net->ipv6.peers = NULL;
3641         inetpeer_invalidate_tree(bp);
3642         kfree(bp);
3643 }
3644
3645 static struct pernet_operations ipv6_inetpeer_ops = {
3646         .init   =       ipv6_inetpeer_init,
3647         .exit   =       ipv6_inetpeer_exit,
3648 };
3649
3650 static struct pernet_operations ip6_route_net_late_ops = {
3651         .init = ip6_route_net_init_late,
3652         .exit = ip6_route_net_exit_late,
3653 };
3654
3655 static struct notifier_block ip6_route_dev_notifier = {
3656         .notifier_call = ip6_route_dev_notify,
3657         .priority = 0,
3658 };
3659
3660 int __init ip6_route_init(void)
3661 {
3662         int ret;
3663         int cpu;
3664
3665         ret = -ENOMEM;
3666         ip6_dst_ops_template.kmem_cachep =
3667                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3668                                   SLAB_HWCACHE_ALIGN, NULL);
3669         if (!ip6_dst_ops_template.kmem_cachep)
3670                 goto out;
3671
3672         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3673         if (ret)
3674                 goto out_kmem_cache;
3675
3676         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3677         if (ret)
3678                 goto out_dst_entries;
3679
3680         ret = register_pernet_subsys(&ip6_route_net_ops);
3681         if (ret)
3682                 goto out_register_inetpeer;
3683
3684         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3685
3686         /* Registering of the loopback is done before this portion of code,
3687          * the loopback reference in rt6_info will not be taken, do it
3688          * manually for init_net */
3689         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3690         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3691   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3692         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3693         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3694         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3695         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3696   #endif
3697         ret = fib6_init();
3698         if (ret)
3699                 goto out_register_subsys;
3700
3701         ret = xfrm6_init();
3702         if (ret)
3703                 goto out_fib6_init;
3704
3705         ret = fib6_rules_init();
3706         if (ret)
3707                 goto xfrm6_init;
3708
3709         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3710         if (ret)
3711                 goto fib6_rules_init;
3712
3713         ret = -ENOBUFS;
3714         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3715             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3716             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3717                 goto out_register_late_subsys;
3718
3719         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3720         if (ret)
3721                 goto out_register_late_subsys;
3722
3723         for_each_possible_cpu(cpu) {
3724                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3725
3726                 INIT_LIST_HEAD(&ul->head);
3727                 spin_lock_init(&ul->lock);
3728         }
3729
3730 out:
3731         return ret;
3732
3733 out_register_late_subsys:
3734         unregister_pernet_subsys(&ip6_route_net_late_ops);
3735 fib6_rules_init:
3736         fib6_rules_cleanup();
3737 xfrm6_init:
3738         xfrm6_fini();
3739 out_fib6_init:
3740         fib6_gc_cleanup();
3741 out_register_subsys:
3742         unregister_pernet_subsys(&ip6_route_net_ops);
3743 out_register_inetpeer:
3744         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3745 out_dst_entries:
3746         dst_entries_destroy(&ip6_dst_blackhole_ops);
3747 out_kmem_cache:
3748         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3749         goto out;
3750 }
3751
3752 void ip6_route_cleanup(void)
3753 {
3754         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3755         unregister_pernet_subsys(&ip6_route_net_late_ops);
3756         fib6_rules_cleanup();
3757         xfrm6_fini();
3758         fib6_gc_cleanup();
3759         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3760         unregister_pernet_subsys(&ip6_route_net_ops);
3761         dst_entries_destroy(&ip6_dst_blackhole_ops);
3762         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3763 }