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