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, &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                         ip6_del_rt(rt);
1302                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1303                         rt->rt6i_node->fn_sernum = -1;
1304                 }
1305         }
1306 }
1307
1308 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1309 {
1310         struct net *net = dev_net(rt->dst.dev);
1311
1312         rt->rt6i_flags |= RTF_MODIFIED;
1313         rt->rt6i_pmtu = mtu;
1314         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1315 }
1316
1317 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1318                                  const struct ipv6hdr *iph, u32 mtu)
1319 {
1320         struct rt6_info *rt6 = (struct rt6_info *)dst;
1321
1322         if (rt6->rt6i_flags & RTF_LOCAL)
1323                 return;
1324
1325         dst_confirm(dst);
1326         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1327         if (mtu >= dst_mtu(dst))
1328                 return;
1329
1330         if (rt6->rt6i_flags & RTF_CACHE) {
1331                 rt6_do_update_pmtu(rt6, mtu);
1332         } else {
1333                 const struct in6_addr *daddr, *saddr;
1334                 struct rt6_info *nrt6;
1335
1336                 if (iph) {
1337                         daddr = &iph->daddr;
1338                         saddr = &iph->saddr;
1339                 } else if (sk) {
1340                         daddr = &sk->sk_v6_daddr;
1341                         saddr = &inet6_sk(sk)->saddr;
1342                 } else {
1343                         return;
1344                 }
1345                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1346                 if (nrt6) {
1347                         rt6_do_update_pmtu(nrt6, mtu);
1348
1349                         /* ip6_ins_rt(nrt6) will bump the
1350                          * rt6->rt6i_node->fn_sernum
1351                          * which will fail the next rt6_check() and
1352                          * invalidate the sk->sk_dst_cache.
1353                          */
1354                         ip6_ins_rt(nrt6);
1355                 }
1356         }
1357 }
1358
1359 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1360                                struct sk_buff *skb, u32 mtu)
1361 {
1362         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1363 }
1364
1365 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1366                      int oif, u32 mark)
1367 {
1368         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1369         struct dst_entry *dst;
1370         struct flowi6 fl6;
1371
1372         memset(&fl6, 0, sizeof(fl6));
1373         fl6.flowi6_oif = oif;
1374         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1375         fl6.daddr = iph->daddr;
1376         fl6.saddr = iph->saddr;
1377         fl6.flowlabel = ip6_flowinfo(iph);
1378
1379         dst = ip6_route_output(net, NULL, &fl6);
1380         if (!dst->error)
1381                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1382         dst_release(dst);
1383 }
1384 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1385
1386 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1387 {
1388         ip6_update_pmtu(skb, sock_net(sk), mtu,
1389                         sk->sk_bound_dev_if, sk->sk_mark);
1390 }
1391 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1392
1393 /* Handle redirects */
1394 struct ip6rd_flowi {
1395         struct flowi6 fl6;
1396         struct in6_addr gateway;
1397 };
1398
1399 static struct rt6_info *__ip6_route_redirect(struct net *net,
1400                                              struct fib6_table *table,
1401                                              struct flowi6 *fl6,
1402                                              int flags)
1403 {
1404         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1405         struct rt6_info *rt;
1406         struct fib6_node *fn;
1407
1408         /* Get the "current" route for this destination and
1409          * check if the redirect has come from approriate router.
1410          *
1411          * RFC 4861 specifies that redirects should only be
1412          * accepted if they come from the nexthop to the target.
1413          * Due to the way the routes are chosen, this notion
1414          * is a bit fuzzy and one might need to check all possible
1415          * routes.
1416          */
1417
1418         read_lock_bh(&table->tb6_lock);
1419         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1420 restart:
1421         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1422                 if (rt6_check_expired(rt))
1423                         continue;
1424                 if (rt->dst.error)
1425                         break;
1426                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1427                         continue;
1428                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1429                         continue;
1430                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1431                         continue;
1432                 break;
1433         }
1434
1435         if (!rt)
1436                 rt = net->ipv6.ip6_null_entry;
1437         else if (rt->dst.error) {
1438                 rt = net->ipv6.ip6_null_entry;
1439                 goto out;
1440         }
1441
1442         if (rt == net->ipv6.ip6_null_entry) {
1443                 fn = fib6_backtrack(fn, &fl6->saddr);
1444                 if (fn)
1445                         goto restart;
1446         }
1447
1448 out:
1449         dst_hold(&rt->dst);
1450
1451         read_unlock_bh(&table->tb6_lock);
1452
1453         return rt;
1454 };
1455
1456 static struct dst_entry *ip6_route_redirect(struct net *net,
1457                                         const struct flowi6 *fl6,
1458                                         const struct in6_addr *gateway)
1459 {
1460         int flags = RT6_LOOKUP_F_HAS_SADDR;
1461         struct ip6rd_flowi rdfl;
1462
1463         rdfl.fl6 = *fl6;
1464         rdfl.gateway = *gateway;
1465
1466         return fib6_rule_lookup(net, &rdfl.fl6,
1467                                 flags, __ip6_route_redirect);
1468 }
1469
1470 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1471 {
1472         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1473         struct dst_entry *dst;
1474         struct flowi6 fl6;
1475
1476         memset(&fl6, 0, sizeof(fl6));
1477         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1478         fl6.flowi6_oif = oif;
1479         fl6.flowi6_mark = mark;
1480         fl6.daddr = iph->daddr;
1481         fl6.saddr = iph->saddr;
1482         fl6.flowlabel = ip6_flowinfo(iph);
1483
1484         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1485         rt6_do_redirect(dst, NULL, skb);
1486         dst_release(dst);
1487 }
1488 EXPORT_SYMBOL_GPL(ip6_redirect);
1489
1490 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1491                             u32 mark)
1492 {
1493         const struct ipv6hdr *iph = ipv6_hdr(skb);
1494         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1495         struct dst_entry *dst;
1496         struct flowi6 fl6;
1497
1498         memset(&fl6, 0, sizeof(fl6));
1499         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1500         fl6.flowi6_oif = oif;
1501         fl6.flowi6_mark = mark;
1502         fl6.daddr = msg->dest;
1503         fl6.saddr = iph->daddr;
1504
1505         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1506         rt6_do_redirect(dst, NULL, skb);
1507         dst_release(dst);
1508 }
1509
1510 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1511 {
1512         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1513 }
1514 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1515
1516 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1517 {
1518         struct net_device *dev = dst->dev;
1519         unsigned int mtu = dst_mtu(dst);
1520         struct net *net = dev_net(dev);
1521
1522         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1523
1524         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1525                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1526
1527         /*
1528          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1529          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1530          * IPV6_MAXPLEN is also valid and means: "any MSS,
1531          * rely only on pmtu discovery"
1532          */
1533         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1534                 mtu = IPV6_MAXPLEN;
1535         return mtu;
1536 }
1537
1538 static unsigned int ip6_mtu(const struct dst_entry *dst)
1539 {
1540         const struct rt6_info *rt = (const struct rt6_info *)dst;
1541         unsigned int mtu = rt->rt6i_pmtu;
1542         struct inet6_dev *idev;
1543
1544         if (mtu)
1545                 goto out;
1546
1547         mtu = dst_metric_raw(dst, RTAX_MTU);
1548         if (mtu)
1549                 goto out;
1550
1551         mtu = IPV6_MIN_MTU;
1552
1553         rcu_read_lock();
1554         idev = __in6_dev_get(dst->dev);
1555         if (idev)
1556                 mtu = idev->cnf.mtu6;
1557         rcu_read_unlock();
1558
1559 out:
1560         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1561 }
1562
1563 static struct dst_entry *icmp6_dst_gc_list;
1564 static DEFINE_SPINLOCK(icmp6_dst_lock);
1565
1566 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1567                                   struct flowi6 *fl6)
1568 {
1569         struct dst_entry *dst;
1570         struct rt6_info *rt;
1571         struct inet6_dev *idev = in6_dev_get(dev);
1572         struct net *net = dev_net(dev);
1573
1574         if (unlikely(!idev))
1575                 return ERR_PTR(-ENODEV);
1576
1577         rt = ip6_dst_alloc(net, dev, 0);
1578         if (unlikely(!rt)) {
1579                 in6_dev_put(idev);
1580                 dst = ERR_PTR(-ENOMEM);
1581                 goto out;
1582         }
1583
1584         rt->dst.flags |= DST_HOST;
1585         rt->dst.output  = ip6_output;
1586         atomic_set(&rt->dst.__refcnt, 1);
1587         rt->rt6i_gateway  = fl6->daddr;
1588         rt->rt6i_dst.addr = fl6->daddr;
1589         rt->rt6i_dst.plen = 128;
1590         rt->rt6i_idev     = idev;
1591         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1592
1593         spin_lock_bh(&icmp6_dst_lock);
1594         rt->dst.next = icmp6_dst_gc_list;
1595         icmp6_dst_gc_list = &rt->dst;
1596         spin_unlock_bh(&icmp6_dst_lock);
1597
1598         fib6_force_start_gc(net);
1599
1600         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1601
1602 out:
1603         return dst;
1604 }
1605
1606 int icmp6_dst_gc(void)
1607 {
1608         struct dst_entry *dst, **pprev;
1609         int more = 0;
1610
1611         spin_lock_bh(&icmp6_dst_lock);
1612         pprev = &icmp6_dst_gc_list;
1613
1614         while ((dst = *pprev) != NULL) {
1615                 if (!atomic_read(&dst->__refcnt)) {
1616                         *pprev = dst->next;
1617                         dst_free(dst);
1618                 } else {
1619                         pprev = &dst->next;
1620                         ++more;
1621                 }
1622         }
1623
1624         spin_unlock_bh(&icmp6_dst_lock);
1625
1626         return more;
1627 }
1628
1629 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1630                             void *arg)
1631 {
1632         struct dst_entry *dst, **pprev;
1633
1634         spin_lock_bh(&icmp6_dst_lock);
1635         pprev = &icmp6_dst_gc_list;
1636         while ((dst = *pprev) != NULL) {
1637                 struct rt6_info *rt = (struct rt6_info *) dst;
1638                 if (func(rt, arg)) {
1639                         *pprev = dst->next;
1640                         dst_free(dst);
1641                 } else {
1642                         pprev = &dst->next;
1643                 }
1644         }
1645         spin_unlock_bh(&icmp6_dst_lock);
1646 }
1647
1648 static int ip6_dst_gc(struct dst_ops *ops)
1649 {
1650         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1651         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1652         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1653         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1654         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1655         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1656         int entries;
1657
1658         entries = dst_entries_get_fast(ops);
1659         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1660             entries <= rt_max_size)
1661                 goto out;
1662
1663         net->ipv6.ip6_rt_gc_expire++;
1664         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1665         entries = dst_entries_get_slow(ops);
1666         if (entries < ops->gc_thresh)
1667                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1668 out:
1669         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1670         return entries > rt_max_size;
1671 }
1672
1673 static int ip6_convert_metrics(struct mx6_config *mxc,
1674                                const struct fib6_config *cfg)
1675 {
1676         bool ecn_ca = false;
1677         struct nlattr *nla;
1678         int remaining;
1679         u32 *mp;
1680
1681         if (!cfg->fc_mx)
1682                 return 0;
1683
1684         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1685         if (unlikely(!mp))
1686                 return -ENOMEM;
1687
1688         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1689                 int type = nla_type(nla);
1690                 u32 val;
1691
1692                 if (!type)
1693                         continue;
1694                 if (unlikely(type > RTAX_MAX))
1695                         goto err;
1696
1697                 if (type == RTAX_CC_ALGO) {
1698                         char tmp[TCP_CA_NAME_MAX];
1699
1700                         nla_strlcpy(tmp, nla, sizeof(tmp));
1701                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1702                         if (val == TCP_CA_UNSPEC)
1703                                 goto err;
1704                 } else {
1705                         val = nla_get_u32(nla);
1706                 }
1707                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1708                         goto err;
1709
1710                 mp[type - 1] = val;
1711                 __set_bit(type - 1, mxc->mx_valid);
1712         }
1713
1714         if (ecn_ca) {
1715                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1716                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1717         }
1718
1719         mxc->mx = mp;
1720         return 0;
1721  err:
1722         kfree(mp);
1723         return -EINVAL;
1724 }
1725
1726 int ip6_route_info_create(struct fib6_config *cfg, struct rt6_info **rt_ret)
1727 {
1728         int err;
1729         struct net *net = cfg->fc_nlinfo.nl_net;
1730         struct rt6_info *rt = NULL;
1731         struct net_device *dev = NULL;
1732         struct inet6_dev *idev = NULL;
1733         struct fib6_table *table;
1734         int addr_type;
1735
1736         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1737                 return -EINVAL;
1738 #ifndef CONFIG_IPV6_SUBTREES
1739         if (cfg->fc_src_len)
1740                 return -EINVAL;
1741 #endif
1742         if (cfg->fc_ifindex) {
1743                 err = -ENODEV;
1744                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1745                 if (!dev)
1746                         goto out;
1747                 idev = in6_dev_get(dev);
1748                 if (!idev)
1749                         goto out;
1750         }
1751
1752         if (cfg->fc_metric == 0)
1753                 cfg->fc_metric = IP6_RT_PRIO_USER;
1754
1755         err = -ENOBUFS;
1756         if (cfg->fc_nlinfo.nlh &&
1757             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1758                 table = fib6_get_table(net, cfg->fc_table);
1759                 if (!table) {
1760                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1761                         table = fib6_new_table(net, cfg->fc_table);
1762                 }
1763         } else {
1764                 table = fib6_new_table(net, cfg->fc_table);
1765         }
1766
1767         if (!table)
1768                 goto out;
1769
1770         rt = ip6_dst_alloc(net, NULL,
1771                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1772
1773         if (!rt) {
1774                 err = -ENOMEM;
1775                 goto out;
1776         }
1777
1778         if (cfg->fc_flags & RTF_EXPIRES)
1779                 rt6_set_expires(rt, jiffies +
1780                                 clock_t_to_jiffies(cfg->fc_expires));
1781         else
1782                 rt6_clean_expires(rt);
1783
1784         if (cfg->fc_protocol == RTPROT_UNSPEC)
1785                 cfg->fc_protocol = RTPROT_BOOT;
1786         rt->rt6i_protocol = cfg->fc_protocol;
1787
1788         addr_type = ipv6_addr_type(&cfg->fc_dst);
1789
1790         if (addr_type & IPV6_ADDR_MULTICAST)
1791                 rt->dst.input = ip6_mc_input;
1792         else if (cfg->fc_flags & RTF_LOCAL)
1793                 rt->dst.input = ip6_input;
1794         else
1795                 rt->dst.input = ip6_forward;
1796
1797         rt->dst.output = ip6_output;
1798
1799         if (cfg->fc_encap) {
1800                 struct lwtunnel_state *lwtstate;
1801
1802                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1803                                            cfg->fc_encap, AF_INET6, cfg,
1804                                            &lwtstate);
1805                 if (err)
1806                         goto out;
1807                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1808                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1809                         rt->dst.lwtstate->orig_output = rt->dst.output;
1810                         rt->dst.output = lwtunnel_output;
1811                 }
1812                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1813                         rt->dst.lwtstate->orig_input = rt->dst.input;
1814                         rt->dst.input = lwtunnel_input;
1815                 }
1816         }
1817
1818         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1819         rt->rt6i_dst.plen = cfg->fc_dst_len;
1820         if (rt->rt6i_dst.plen == 128)
1821                 rt->dst.flags |= DST_HOST;
1822
1823 #ifdef CONFIG_IPV6_SUBTREES
1824         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1825         rt->rt6i_src.plen = cfg->fc_src_len;
1826 #endif
1827
1828         rt->rt6i_metric = cfg->fc_metric;
1829
1830         /* We cannot add true routes via loopback here,
1831            they would result in kernel looping; promote them to reject routes
1832          */
1833         if ((cfg->fc_flags & RTF_REJECT) ||
1834             (dev && (dev->flags & IFF_LOOPBACK) &&
1835              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1836              !(cfg->fc_flags & RTF_LOCAL))) {
1837                 /* hold loopback dev/idev if we haven't done so. */
1838                 if (dev != net->loopback_dev) {
1839                         if (dev) {
1840                                 dev_put(dev);
1841                                 in6_dev_put(idev);
1842                         }
1843                         dev = net->loopback_dev;
1844                         dev_hold(dev);
1845                         idev = in6_dev_get(dev);
1846                         if (!idev) {
1847                                 err = -ENODEV;
1848                                 goto out;
1849                         }
1850                 }
1851                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1852                 switch (cfg->fc_type) {
1853                 case RTN_BLACKHOLE:
1854                         rt->dst.error = -EINVAL;
1855                         rt->dst.output = dst_discard_sk;
1856                         rt->dst.input = dst_discard;
1857                         break;
1858                 case RTN_PROHIBIT:
1859                         rt->dst.error = -EACCES;
1860                         rt->dst.output = ip6_pkt_prohibit_out;
1861                         rt->dst.input = ip6_pkt_prohibit;
1862                         break;
1863                 case RTN_THROW:
1864                 case RTN_UNREACHABLE:
1865                 default:
1866                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1867                                         : (cfg->fc_type == RTN_UNREACHABLE)
1868                                         ? -EHOSTUNREACH : -ENETUNREACH;
1869                         rt->dst.output = ip6_pkt_discard_out;
1870                         rt->dst.input = ip6_pkt_discard;
1871                         break;
1872                 }
1873                 goto install_route;
1874         }
1875
1876         if (cfg->fc_flags & RTF_GATEWAY) {
1877                 const struct in6_addr *gw_addr;
1878                 int gwa_type;
1879
1880                 gw_addr = &cfg->fc_gateway;
1881                 gwa_type = ipv6_addr_type(gw_addr);
1882
1883                 /* if gw_addr is local we will fail to detect this in case
1884                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1885                  * will return already-added prefix route via interface that
1886                  * prefix route was assigned to, which might be non-loopback.
1887                  */
1888                 err = -EINVAL;
1889                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1890                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1891                                             dev : NULL, 0, 0))
1892                         goto out;
1893
1894                 rt->rt6i_gateway = *gw_addr;
1895
1896                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1897                         struct rt6_info *grt;
1898
1899                         /* IPv6 strictly inhibits using not link-local
1900                            addresses as nexthop address.
1901                            Otherwise, router will not able to send redirects.
1902                            It is very good, but in some (rare!) circumstances
1903                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1904                            some exceptions. --ANK
1905                          */
1906                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1907                                 goto out;
1908
1909                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1910
1911                         err = -EHOSTUNREACH;
1912                         if (!grt)
1913                                 goto out;
1914                         if (dev) {
1915                                 if (dev != grt->dst.dev) {
1916                                         ip6_rt_put(grt);
1917                                         goto out;
1918                                 }
1919                         } else {
1920                                 dev = grt->dst.dev;
1921                                 idev = grt->rt6i_idev;
1922                                 dev_hold(dev);
1923                                 in6_dev_hold(grt->rt6i_idev);
1924                         }
1925                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1926                                 err = 0;
1927                         ip6_rt_put(grt);
1928
1929                         if (err)
1930                                 goto out;
1931                 }
1932                 err = -EINVAL;
1933                 if (!dev || (dev->flags & IFF_LOOPBACK))
1934                         goto out;
1935         }
1936
1937         err = -ENODEV;
1938         if (!dev)
1939                 goto out;
1940
1941         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1942                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1943                         err = -EINVAL;
1944                         goto out;
1945                 }
1946                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1947                 rt->rt6i_prefsrc.plen = 128;
1948         } else
1949                 rt->rt6i_prefsrc.plen = 0;
1950
1951         rt->rt6i_flags = cfg->fc_flags;
1952
1953 install_route:
1954         rt->dst.dev = dev;
1955         rt->rt6i_idev = idev;
1956         rt->rt6i_table = table;
1957
1958         cfg->fc_nlinfo.nl_net = dev_net(dev);
1959
1960         *rt_ret = rt;
1961
1962         return 0;
1963 out:
1964         if (dev)
1965                 dev_put(dev);
1966         if (idev)
1967                 in6_dev_put(idev);
1968         if (rt)
1969                 dst_free(&rt->dst);
1970
1971         *rt_ret = NULL;
1972
1973         return err;
1974 }
1975
1976 int ip6_route_add(struct fib6_config *cfg)
1977 {
1978         struct mx6_config mxc = { .mx = NULL, };
1979         struct rt6_info *rt = NULL;
1980         int err;
1981
1982         err = ip6_route_info_create(cfg, &rt);
1983         if (err)
1984                 goto out;
1985
1986         err = ip6_convert_metrics(&mxc, cfg);
1987         if (err)
1988                 goto out;
1989
1990         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
1991
1992         kfree(mxc.mx);
1993
1994         return err;
1995 out:
1996         if (rt)
1997                 dst_free(&rt->dst);
1998
1999         return err;
2000 }
2001
2002 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2003 {
2004         int err;
2005         struct fib6_table *table;
2006         struct net *net = dev_net(rt->dst.dev);
2007
2008         if (rt == net->ipv6.ip6_null_entry ||
2009             rt->dst.flags & DST_NOCACHE) {
2010                 err = -ENOENT;
2011                 goto out;
2012         }
2013
2014         table = rt->rt6i_table;
2015         write_lock_bh(&table->tb6_lock);
2016         err = fib6_del(rt, info);
2017         write_unlock_bh(&table->tb6_lock);
2018
2019 out:
2020         ip6_rt_put(rt);
2021         return err;
2022 }
2023
2024 int ip6_del_rt(struct rt6_info *rt)
2025 {
2026         struct nl_info info = {
2027                 .nl_net = dev_net(rt->dst.dev),
2028         };
2029         return __ip6_del_rt(rt, &info);
2030 }
2031
2032 static int ip6_route_del(struct fib6_config *cfg)
2033 {
2034         struct fib6_table *table;
2035         struct fib6_node *fn;
2036         struct rt6_info *rt;
2037         int err = -ESRCH;
2038
2039         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2040         if (!table)
2041                 return err;
2042
2043         read_lock_bh(&table->tb6_lock);
2044
2045         fn = fib6_locate(&table->tb6_root,
2046                          &cfg->fc_dst, cfg->fc_dst_len,
2047                          &cfg->fc_src, cfg->fc_src_len);
2048
2049         if (fn) {
2050                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2051                         if ((rt->rt6i_flags & RTF_CACHE) &&
2052                             !(cfg->fc_flags & RTF_CACHE))
2053                                 continue;
2054                         if (cfg->fc_ifindex &&
2055                             (!rt->dst.dev ||
2056                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2057                                 continue;
2058                         if (cfg->fc_flags & RTF_GATEWAY &&
2059                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2060                                 continue;
2061                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2062                                 continue;
2063                         dst_hold(&rt->dst);
2064                         read_unlock_bh(&table->tb6_lock);
2065
2066                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2067                 }
2068         }
2069         read_unlock_bh(&table->tb6_lock);
2070
2071         return err;
2072 }
2073
2074 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2075 {
2076         struct net *net = dev_net(skb->dev);
2077         struct netevent_redirect netevent;
2078         struct rt6_info *rt, *nrt = NULL;
2079         struct ndisc_options ndopts;
2080         struct inet6_dev *in6_dev;
2081         struct neighbour *neigh;
2082         struct rd_msg *msg;
2083         int optlen, on_link;
2084         u8 *lladdr;
2085
2086         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2087         optlen -= sizeof(*msg);
2088
2089         if (optlen < 0) {
2090                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2091                 return;
2092         }
2093
2094         msg = (struct rd_msg *)icmp6_hdr(skb);
2095
2096         if (ipv6_addr_is_multicast(&msg->dest)) {
2097                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2098                 return;
2099         }
2100
2101         on_link = 0;
2102         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2103                 on_link = 1;
2104         } else if (ipv6_addr_type(&msg->target) !=
2105                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2106                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2107                 return;
2108         }
2109
2110         in6_dev = __in6_dev_get(skb->dev);
2111         if (!in6_dev)
2112                 return;
2113         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2114                 return;
2115
2116         /* RFC2461 8.1:
2117          *      The IP source address of the Redirect MUST be the same as the current
2118          *      first-hop router for the specified ICMP Destination Address.
2119          */
2120
2121         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2122                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2123                 return;
2124         }
2125
2126         lladdr = NULL;
2127         if (ndopts.nd_opts_tgt_lladdr) {
2128                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2129                                              skb->dev);
2130                 if (!lladdr) {
2131                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2132                         return;
2133                 }
2134         }
2135
2136         rt = (struct rt6_info *) dst;
2137         if (rt == net->ipv6.ip6_null_entry) {
2138                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2139                 return;
2140         }
2141
2142         /* Redirect received -> path was valid.
2143          * Look, redirects are sent only in response to data packets,
2144          * so that this nexthop apparently is reachable. --ANK
2145          */
2146         dst_confirm(&rt->dst);
2147
2148         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2149         if (!neigh)
2150                 return;
2151
2152         /*
2153          *      We have finally decided to accept it.
2154          */
2155
2156         neigh_update(neigh, lladdr, NUD_STALE,
2157                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2158                      NEIGH_UPDATE_F_OVERRIDE|
2159                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2160                                      NEIGH_UPDATE_F_ISROUTER))
2161                      );
2162
2163         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2164         if (!nrt)
2165                 goto out;
2166
2167         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2168         if (on_link)
2169                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2170
2171         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2172
2173         if (ip6_ins_rt(nrt))
2174                 goto out;
2175
2176         netevent.old = &rt->dst;
2177         netevent.new = &nrt->dst;
2178         netevent.daddr = &msg->dest;
2179         netevent.neigh = neigh;
2180         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2181
2182         if (rt->rt6i_flags & RTF_CACHE) {
2183                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2184                 ip6_del_rt(rt);
2185         }
2186
2187 out:
2188         neigh_release(neigh);
2189 }
2190
2191 /*
2192  *      Misc support functions
2193  */
2194
2195 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2196 {
2197         BUG_ON(from->dst.from);
2198
2199         rt->rt6i_flags &= ~RTF_EXPIRES;
2200         dst_hold(&from->dst);
2201         rt->dst.from = &from->dst;
2202         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2203 }
2204
2205 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2206 {
2207         rt->dst.input = ort->dst.input;
2208         rt->dst.output = ort->dst.output;
2209         rt->rt6i_dst = ort->rt6i_dst;
2210         rt->dst.error = ort->dst.error;
2211         rt->rt6i_idev = ort->rt6i_idev;
2212         if (rt->rt6i_idev)
2213                 in6_dev_hold(rt->rt6i_idev);
2214         rt->dst.lastuse = jiffies;
2215         rt->rt6i_gateway = ort->rt6i_gateway;
2216         rt->rt6i_flags = ort->rt6i_flags;
2217         rt6_set_from(rt, ort);
2218         rt->rt6i_metric = ort->rt6i_metric;
2219 #ifdef CONFIG_IPV6_SUBTREES
2220         rt->rt6i_src = ort->rt6i_src;
2221 #endif
2222         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2223         rt->rt6i_table = ort->rt6i_table;
2224         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2225 }
2226
2227 #ifdef CONFIG_IPV6_ROUTE_INFO
2228 static struct rt6_info *rt6_get_route_info(struct net *net,
2229                                            const struct in6_addr *prefix, int prefixlen,
2230                                            const struct in6_addr *gwaddr, int ifindex)
2231 {
2232         struct fib6_node *fn;
2233         struct rt6_info *rt = NULL;
2234         struct fib6_table *table;
2235
2236         table = fib6_get_table(net, RT6_TABLE_INFO);
2237         if (!table)
2238                 return NULL;
2239
2240         read_lock_bh(&table->tb6_lock);
2241         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2242         if (!fn)
2243                 goto out;
2244
2245         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2246                 if (rt->dst.dev->ifindex != ifindex)
2247                         continue;
2248                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2249                         continue;
2250                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2251                         continue;
2252                 dst_hold(&rt->dst);
2253                 break;
2254         }
2255 out:
2256         read_unlock_bh(&table->tb6_lock);
2257         return rt;
2258 }
2259
2260 static struct rt6_info *rt6_add_route_info(struct net *net,
2261                                            const struct in6_addr *prefix, int prefixlen,
2262                                            const struct in6_addr *gwaddr, int ifindex,
2263                                            unsigned int pref)
2264 {
2265         struct fib6_config cfg = {
2266                 .fc_table       = RT6_TABLE_INFO,
2267                 .fc_metric      = IP6_RT_PRIO_USER,
2268                 .fc_ifindex     = ifindex,
2269                 .fc_dst_len     = prefixlen,
2270                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2271                                   RTF_UP | RTF_PREF(pref),
2272                 .fc_nlinfo.portid = 0,
2273                 .fc_nlinfo.nlh = NULL,
2274                 .fc_nlinfo.nl_net = net,
2275         };
2276
2277         cfg.fc_dst = *prefix;
2278         cfg.fc_gateway = *gwaddr;
2279
2280         /* We should treat it as a default route if prefix length is 0. */
2281         if (!prefixlen)
2282                 cfg.fc_flags |= RTF_DEFAULT;
2283
2284         ip6_route_add(&cfg);
2285
2286         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2287 }
2288 #endif
2289
2290 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2291 {
2292         struct rt6_info *rt;
2293         struct fib6_table *table;
2294
2295         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2296         if (!table)
2297                 return NULL;
2298
2299         read_lock_bh(&table->tb6_lock);
2300         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2301                 if (dev == rt->dst.dev &&
2302                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2303                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2304                         break;
2305         }
2306         if (rt)
2307                 dst_hold(&rt->dst);
2308         read_unlock_bh(&table->tb6_lock);
2309         return rt;
2310 }
2311
2312 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2313                                      struct net_device *dev,
2314                                      unsigned int pref)
2315 {
2316         struct fib6_config cfg = {
2317                 .fc_table       = RT6_TABLE_DFLT,
2318                 .fc_metric      = IP6_RT_PRIO_USER,
2319                 .fc_ifindex     = dev->ifindex,
2320                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2321                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2322                 .fc_nlinfo.portid = 0,
2323                 .fc_nlinfo.nlh = NULL,
2324                 .fc_nlinfo.nl_net = dev_net(dev),
2325         };
2326
2327         cfg.fc_gateway = *gwaddr;
2328
2329         ip6_route_add(&cfg);
2330
2331         return rt6_get_dflt_router(gwaddr, dev);
2332 }
2333
2334 void rt6_purge_dflt_routers(struct net *net)
2335 {
2336         struct rt6_info *rt;
2337         struct fib6_table *table;
2338
2339         /* NOTE: Keep consistent with rt6_get_dflt_router */
2340         table = fib6_get_table(net, RT6_TABLE_DFLT);
2341         if (!table)
2342                 return;
2343
2344 restart:
2345         read_lock_bh(&table->tb6_lock);
2346         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2347                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2348                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2349                         dst_hold(&rt->dst);
2350                         read_unlock_bh(&table->tb6_lock);
2351                         ip6_del_rt(rt);
2352                         goto restart;
2353                 }
2354         }
2355         read_unlock_bh(&table->tb6_lock);
2356 }
2357
2358 static void rtmsg_to_fib6_config(struct net *net,
2359                                  struct in6_rtmsg *rtmsg,
2360                                  struct fib6_config *cfg)
2361 {
2362         memset(cfg, 0, sizeof(*cfg));
2363
2364         cfg->fc_table = RT6_TABLE_MAIN;
2365         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2366         cfg->fc_metric = rtmsg->rtmsg_metric;
2367         cfg->fc_expires = rtmsg->rtmsg_info;
2368         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2369         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2370         cfg->fc_flags = rtmsg->rtmsg_flags;
2371
2372         cfg->fc_nlinfo.nl_net = net;
2373
2374         cfg->fc_dst = rtmsg->rtmsg_dst;
2375         cfg->fc_src = rtmsg->rtmsg_src;
2376         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2377 }
2378
2379 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2380 {
2381         struct fib6_config cfg;
2382         struct in6_rtmsg rtmsg;
2383         int err;
2384
2385         switch (cmd) {
2386         case SIOCADDRT:         /* Add a route */
2387         case SIOCDELRT:         /* Delete a route */
2388                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2389                         return -EPERM;
2390                 err = copy_from_user(&rtmsg, arg,
2391                                      sizeof(struct in6_rtmsg));
2392                 if (err)
2393                         return -EFAULT;
2394
2395                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2396
2397                 rtnl_lock();
2398                 switch (cmd) {
2399                 case SIOCADDRT:
2400                         err = ip6_route_add(&cfg);
2401                         break;
2402                 case SIOCDELRT:
2403                         err = ip6_route_del(&cfg);
2404                         break;
2405                 default:
2406                         err = -EINVAL;
2407                 }
2408                 rtnl_unlock();
2409
2410                 return err;
2411         }
2412
2413         return -EINVAL;
2414 }
2415
2416 /*
2417  *      Drop the packet on the floor
2418  */
2419
2420 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2421 {
2422         int type;
2423         struct dst_entry *dst = skb_dst(skb);
2424         switch (ipstats_mib_noroutes) {
2425         case IPSTATS_MIB_INNOROUTES:
2426                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2427                 if (type == IPV6_ADDR_ANY) {
2428                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2429                                       IPSTATS_MIB_INADDRERRORS);
2430                         break;
2431                 }
2432                 /* FALLTHROUGH */
2433         case IPSTATS_MIB_OUTNOROUTES:
2434                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2435                               ipstats_mib_noroutes);
2436                 break;
2437         }
2438         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2439         kfree_skb(skb);
2440         return 0;
2441 }
2442
2443 static int ip6_pkt_discard(struct sk_buff *skb)
2444 {
2445         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2446 }
2447
2448 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2449 {
2450         skb->dev = skb_dst(skb)->dev;
2451         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2452 }
2453
2454 static int ip6_pkt_prohibit(struct sk_buff *skb)
2455 {
2456         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2457 }
2458
2459 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2460 {
2461         skb->dev = skb_dst(skb)->dev;
2462         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2463 }
2464
2465 /*
2466  *      Allocate a dst for local (unicast / anycast) address.
2467  */
2468
2469 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2470                                     const struct in6_addr *addr,
2471                                     bool anycast)
2472 {
2473         struct net *net = dev_net(idev->dev);
2474         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2475                                             DST_NOCOUNT);
2476         if (!rt)
2477                 return ERR_PTR(-ENOMEM);
2478
2479         in6_dev_hold(idev);
2480
2481         rt->dst.flags |= DST_HOST;
2482         rt->dst.input = ip6_input;
2483         rt->dst.output = ip6_output;
2484         rt->rt6i_idev = idev;
2485
2486         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2487         if (anycast)
2488                 rt->rt6i_flags |= RTF_ANYCAST;
2489         else
2490                 rt->rt6i_flags |= RTF_LOCAL;
2491
2492         rt->rt6i_gateway  = *addr;
2493         rt->rt6i_dst.addr = *addr;
2494         rt->rt6i_dst.plen = 128;
2495         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2496         rt->dst.flags |= DST_NOCACHE;
2497
2498         atomic_set(&rt->dst.__refcnt, 1);
2499
2500         return rt;
2501 }
2502
2503 int ip6_route_get_saddr(struct net *net,
2504                         struct rt6_info *rt,
2505                         const struct in6_addr *daddr,
2506                         unsigned int prefs,
2507                         struct in6_addr *saddr)
2508 {
2509         struct inet6_dev *idev =
2510                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2511         int err = 0;
2512         if (rt && rt->rt6i_prefsrc.plen)
2513                 *saddr = rt->rt6i_prefsrc.addr;
2514         else
2515                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2516                                          daddr, prefs, saddr);
2517         return err;
2518 }
2519
2520 /* remove deleted ip from prefsrc entries */
2521 struct arg_dev_net_ip {
2522         struct net_device *dev;
2523         struct net *net;
2524         struct in6_addr *addr;
2525 };
2526
2527 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2528 {
2529         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2530         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2531         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2532
2533         if (((void *)rt->dst.dev == dev || !dev) &&
2534             rt != net->ipv6.ip6_null_entry &&
2535             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2536                 /* remove prefsrc entry */
2537                 rt->rt6i_prefsrc.plen = 0;
2538         }
2539         return 0;
2540 }
2541
2542 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2543 {
2544         struct net *net = dev_net(ifp->idev->dev);
2545         struct arg_dev_net_ip adni = {
2546                 .dev = ifp->idev->dev,
2547                 .net = net,
2548                 .addr = &ifp->addr,
2549         };
2550         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2551 }
2552
2553 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2554 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2555
2556 /* Remove routers and update dst entries when gateway turn into host. */
2557 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2558 {
2559         struct in6_addr *gateway = (struct in6_addr *)arg;
2560
2561         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2562              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2563              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2564                 return -1;
2565         }
2566         return 0;
2567 }
2568
2569 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2570 {
2571         fib6_clean_all(net, fib6_clean_tohost, gateway);
2572 }
2573
2574 struct arg_dev_net {
2575         struct net_device *dev;
2576         struct net *net;
2577 };
2578
2579 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2580 {
2581         const struct arg_dev_net *adn = arg;
2582         const struct net_device *dev = adn->dev;
2583
2584         if ((rt->dst.dev == dev || !dev) &&
2585             rt != adn->net->ipv6.ip6_null_entry)
2586                 return -1;
2587
2588         return 0;
2589 }
2590
2591 void rt6_ifdown(struct net *net, struct net_device *dev)
2592 {
2593         struct arg_dev_net adn = {
2594                 .dev = dev,
2595                 .net = net,
2596         };
2597
2598         fib6_clean_all(net, fib6_ifdown, &adn);
2599         icmp6_clean_all(fib6_ifdown, &adn);
2600         rt6_uncached_list_flush_dev(net, dev);
2601 }
2602
2603 struct rt6_mtu_change_arg {
2604         struct net_device *dev;
2605         unsigned int mtu;
2606 };
2607
2608 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2609 {
2610         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2611         struct inet6_dev *idev;
2612
2613         /* In IPv6 pmtu discovery is not optional,
2614            so that RTAX_MTU lock cannot disable it.
2615            We still use this lock to block changes
2616            caused by addrconf/ndisc.
2617         */
2618
2619         idev = __in6_dev_get(arg->dev);
2620         if (!idev)
2621                 return 0;
2622
2623         /* For administrative MTU increase, there is no way to discover
2624            IPv6 PMTU increase, so PMTU increase should be updated here.
2625            Since RFC 1981 doesn't include administrative MTU increase
2626            update PMTU increase is a MUST. (i.e. jumbo frame)
2627          */
2628         /*
2629            If new MTU is less than route PMTU, this new MTU will be the
2630            lowest MTU in the path, update the route PMTU to reflect PMTU
2631            decreases; if new MTU is greater than route PMTU, and the
2632            old MTU is the lowest MTU in the path, update the route PMTU
2633            to reflect the increase. In this case if the other nodes' MTU
2634            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2635            PMTU discouvery.
2636          */
2637         if (rt->dst.dev == arg->dev &&
2638             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2639                 if (rt->rt6i_flags & RTF_CACHE) {
2640                         /* For RTF_CACHE with rt6i_pmtu == 0
2641                          * (i.e. a redirected route),
2642                          * the metrics of its rt->dst.from has already
2643                          * been updated.
2644                          */
2645                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2646                                 rt->rt6i_pmtu = arg->mtu;
2647                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2648                            (dst_mtu(&rt->dst) < arg->mtu &&
2649                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2650                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2651                 }
2652         }
2653         return 0;
2654 }
2655
2656 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2657 {
2658         struct rt6_mtu_change_arg arg = {
2659                 .dev = dev,
2660                 .mtu = mtu,
2661         };
2662
2663         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2664 }
2665
2666 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2667         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2668         [RTA_OIF]               = { .type = NLA_U32 },
2669         [RTA_IIF]               = { .type = NLA_U32 },
2670         [RTA_PRIORITY]          = { .type = NLA_U32 },
2671         [RTA_METRICS]           = { .type = NLA_NESTED },
2672         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2673         [RTA_PREF]              = { .type = NLA_U8 },
2674         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2675         [RTA_ENCAP]             = { .type = NLA_NESTED },
2676 };
2677
2678 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2679                               struct fib6_config *cfg)
2680 {
2681         struct rtmsg *rtm;
2682         struct nlattr *tb[RTA_MAX+1];
2683         unsigned int pref;
2684         int err;
2685
2686         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2687         if (err < 0)
2688                 goto errout;
2689
2690         err = -EINVAL;
2691         rtm = nlmsg_data(nlh);
2692         memset(cfg, 0, sizeof(*cfg));
2693
2694         cfg->fc_table = rtm->rtm_table;
2695         cfg->fc_dst_len = rtm->rtm_dst_len;
2696         cfg->fc_src_len = rtm->rtm_src_len;
2697         cfg->fc_flags = RTF_UP;
2698         cfg->fc_protocol = rtm->rtm_protocol;
2699         cfg->fc_type = rtm->rtm_type;
2700
2701         if (rtm->rtm_type == RTN_UNREACHABLE ||
2702             rtm->rtm_type == RTN_BLACKHOLE ||
2703             rtm->rtm_type == RTN_PROHIBIT ||
2704             rtm->rtm_type == RTN_THROW)
2705                 cfg->fc_flags |= RTF_REJECT;
2706
2707         if (rtm->rtm_type == RTN_LOCAL)
2708                 cfg->fc_flags |= RTF_LOCAL;
2709
2710         if (rtm->rtm_flags & RTM_F_CLONED)
2711                 cfg->fc_flags |= RTF_CACHE;
2712
2713         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2714         cfg->fc_nlinfo.nlh = nlh;
2715         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2716
2717         if (tb[RTA_GATEWAY]) {
2718                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2719                 cfg->fc_flags |= RTF_GATEWAY;
2720         }
2721
2722         if (tb[RTA_DST]) {
2723                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2724
2725                 if (nla_len(tb[RTA_DST]) < plen)
2726                         goto errout;
2727
2728                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2729         }
2730
2731         if (tb[RTA_SRC]) {
2732                 int plen = (rtm->rtm_src_len + 7) >> 3;
2733
2734                 if (nla_len(tb[RTA_SRC]) < plen)
2735                         goto errout;
2736
2737                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2738         }
2739
2740         if (tb[RTA_PREFSRC])
2741                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2742
2743         if (tb[RTA_OIF])
2744                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2745
2746         if (tb[RTA_PRIORITY])
2747                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2748
2749         if (tb[RTA_METRICS]) {
2750                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2751                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2752         }
2753
2754         if (tb[RTA_TABLE])
2755                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2756
2757         if (tb[RTA_MULTIPATH]) {
2758                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2759                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2760         }
2761
2762         if (tb[RTA_PREF]) {
2763                 pref = nla_get_u8(tb[RTA_PREF]);
2764                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2765                     pref != ICMPV6_ROUTER_PREF_HIGH)
2766                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2767                 cfg->fc_flags |= RTF_PREF(pref);
2768         }
2769
2770         if (tb[RTA_ENCAP])
2771                 cfg->fc_encap = tb[RTA_ENCAP];
2772
2773         if (tb[RTA_ENCAP_TYPE])
2774                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2775
2776         err = 0;
2777 errout:
2778         return err;
2779 }
2780
2781 struct rt6_nh {
2782         struct rt6_info *rt6_info;
2783         struct fib6_config r_cfg;
2784         struct mx6_config mxc;
2785         struct list_head next;
2786 };
2787
2788 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2789 {
2790         struct rt6_nh *nh;
2791
2792         list_for_each_entry(nh, rt6_nh_list, next) {
2793                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2794                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2795                         nh->r_cfg.fc_ifindex);
2796         }
2797 }
2798
2799 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2800                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2801 {
2802         struct rt6_nh *nh;
2803         struct rt6_info *rtnh;
2804         int err = -EEXIST;
2805
2806         list_for_each_entry(nh, rt6_nh_list, next) {
2807                 /* check if rt6_info already exists */
2808                 rtnh = nh->rt6_info;
2809
2810                 if (rtnh->dst.dev == rt->dst.dev &&
2811                     rtnh->rt6i_idev == rt->rt6i_idev &&
2812                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2813                                     &rt->rt6i_gateway))
2814                         return err;
2815         }
2816
2817         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2818         if (!nh)
2819                 return -ENOMEM;
2820         nh->rt6_info = rt;
2821         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2822         if (err) {
2823                 kfree(nh);
2824                 return err;
2825         }
2826         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2827         list_add_tail(&nh->next, rt6_nh_list);
2828
2829         return 0;
2830 }
2831
2832 static int ip6_route_multipath_add(struct fib6_config *cfg)
2833 {
2834         struct fib6_config r_cfg;
2835         struct rtnexthop *rtnh;
2836         struct rt6_info *rt;
2837         struct rt6_nh *err_nh;
2838         struct rt6_nh *nh, *nh_safe;
2839         int remaining;
2840         int attrlen;
2841         int err = 1;
2842         int nhn = 0;
2843         int replace = (cfg->fc_nlinfo.nlh &&
2844                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2845         LIST_HEAD(rt6_nh_list);
2846
2847         remaining = cfg->fc_mp_len;
2848         rtnh = (struct rtnexthop *)cfg->fc_mp;
2849
2850         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2851          * rt6_info structs per nexthop
2852          */
2853         while (rtnh_ok(rtnh, remaining)) {
2854                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2855                 if (rtnh->rtnh_ifindex)
2856                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2857
2858                 attrlen = rtnh_attrlen(rtnh);
2859                 if (attrlen > 0) {
2860                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2861
2862                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2863                         if (nla) {
2864                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2865                                 r_cfg.fc_flags |= RTF_GATEWAY;
2866                         }
2867                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2868                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2869                         if (nla)
2870                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2871                 }
2872
2873                 err = ip6_route_info_create(&r_cfg, &rt);
2874                 if (err)
2875                         goto cleanup;
2876
2877                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2878                 if (err) {
2879                         dst_free(&rt->dst);
2880                         goto cleanup;
2881                 }
2882
2883                 rtnh = rtnh_next(rtnh, &remaining);
2884         }
2885
2886         err_nh = NULL;
2887         list_for_each_entry(nh, &rt6_nh_list, next) {
2888                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2889                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2890                 nh->rt6_info = NULL;
2891                 if (err) {
2892                         if (replace && nhn)
2893                                 ip6_print_replace_route_err(&rt6_nh_list);
2894                         err_nh = nh;
2895                         goto add_errout;
2896                 }
2897
2898                 /* Because each route is added like a single route we remove
2899                  * these flags after the first nexthop: if there is a collision,
2900                  * we have already failed to add the first nexthop:
2901                  * fib6_add_rt2node() has rejected it; when replacing, old
2902                  * nexthops have been replaced by first new, the rest should
2903                  * be added to it.
2904                  */
2905                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2906                                                      NLM_F_REPLACE);
2907                 nhn++;
2908         }
2909
2910         goto cleanup;
2911
2912 add_errout:
2913         /* Delete routes that were already added */
2914         list_for_each_entry(nh, &rt6_nh_list, next) {
2915                 if (err_nh == nh)
2916                         break;
2917                 ip6_route_del(&nh->r_cfg);
2918         }
2919
2920 cleanup:
2921         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2922                 if (nh->rt6_info)
2923                         dst_free(&nh->rt6_info->dst);
2924                 kfree(nh->mxc.mx);
2925                 list_del(&nh->next);
2926                 kfree(nh);
2927         }
2928
2929         return err;
2930 }
2931
2932 static int ip6_route_multipath_del(struct fib6_config *cfg)
2933 {
2934         struct fib6_config r_cfg;
2935         struct rtnexthop *rtnh;
2936         int remaining;
2937         int attrlen;
2938         int err = 1, last_err = 0;
2939
2940         remaining = cfg->fc_mp_len;
2941         rtnh = (struct rtnexthop *)cfg->fc_mp;
2942
2943         /* Parse a Multipath Entry */
2944         while (rtnh_ok(rtnh, remaining)) {
2945                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2946                 if (rtnh->rtnh_ifindex)
2947                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2948
2949                 attrlen = rtnh_attrlen(rtnh);
2950                 if (attrlen > 0) {
2951                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2952
2953                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2954                         if (nla) {
2955                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2956                                 r_cfg.fc_flags |= RTF_GATEWAY;
2957                         }
2958                 }
2959                 err = ip6_route_del(&r_cfg);
2960                 if (err)
2961                         last_err = err;
2962
2963                 rtnh = rtnh_next(rtnh, &remaining);
2964         }
2965
2966         return last_err;
2967 }
2968
2969 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2970 {
2971         struct fib6_config cfg;
2972         int err;
2973
2974         err = rtm_to_fib6_config(skb, nlh, &cfg);
2975         if (err < 0)
2976                 return err;
2977
2978         if (cfg.fc_mp)
2979                 return ip6_route_multipath_del(&cfg);
2980         else
2981                 return ip6_route_del(&cfg);
2982 }
2983
2984 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2985 {
2986         struct fib6_config cfg;
2987         int err;
2988
2989         err = rtm_to_fib6_config(skb, nlh, &cfg);
2990         if (err < 0)
2991                 return err;
2992
2993         if (cfg.fc_mp)
2994                 return ip6_route_multipath_add(&cfg);
2995         else
2996                 return ip6_route_add(&cfg);
2997 }
2998
2999 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3000 {
3001         return NLMSG_ALIGN(sizeof(struct rtmsg))
3002                + nla_total_size(16) /* RTA_SRC */
3003                + nla_total_size(16) /* RTA_DST */
3004                + nla_total_size(16) /* RTA_GATEWAY */
3005                + nla_total_size(16) /* RTA_PREFSRC */
3006                + nla_total_size(4) /* RTA_TABLE */
3007                + nla_total_size(4) /* RTA_IIF */
3008                + nla_total_size(4) /* RTA_OIF */
3009                + nla_total_size(4) /* RTA_PRIORITY */
3010                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3011                + nla_total_size(sizeof(struct rta_cacheinfo))
3012                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3013                + nla_total_size(1) /* RTA_PREF */
3014                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3015 }
3016
3017 static int rt6_fill_node(struct net *net,
3018                          struct sk_buff *skb, struct rt6_info *rt,
3019                          struct in6_addr *dst, struct in6_addr *src,
3020                          int iif, int type, u32 portid, u32 seq,
3021                          int prefix, int nowait, unsigned int flags)
3022 {
3023         u32 metrics[RTAX_MAX];
3024         struct rtmsg *rtm;
3025         struct nlmsghdr *nlh;
3026         long expires;
3027         u32 table;
3028
3029         if (prefix) {   /* user wants prefix routes only */
3030                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3031                         /* success since this is not a prefix route */
3032                         return 1;
3033                 }
3034         }
3035
3036         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3037         if (!nlh)
3038                 return -EMSGSIZE;
3039
3040         rtm = nlmsg_data(nlh);
3041         rtm->rtm_family = AF_INET6;
3042         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3043         rtm->rtm_src_len = rt->rt6i_src.plen;
3044         rtm->rtm_tos = 0;
3045         if (rt->rt6i_table)
3046                 table = rt->rt6i_table->tb6_id;
3047         else
3048                 table = RT6_TABLE_UNSPEC;
3049         rtm->rtm_table = table;
3050         if (nla_put_u32(skb, RTA_TABLE, table))
3051                 goto nla_put_failure;
3052         if (rt->rt6i_flags & RTF_REJECT) {
3053                 switch (rt->dst.error) {
3054                 case -EINVAL:
3055                         rtm->rtm_type = RTN_BLACKHOLE;
3056                         break;
3057                 case -EACCES:
3058                         rtm->rtm_type = RTN_PROHIBIT;
3059                         break;
3060                 case -EAGAIN:
3061                         rtm->rtm_type = RTN_THROW;
3062                         break;
3063                 default:
3064                         rtm->rtm_type = RTN_UNREACHABLE;
3065                         break;
3066                 }
3067         }
3068         else if (rt->rt6i_flags & RTF_LOCAL)
3069                 rtm->rtm_type = RTN_LOCAL;
3070         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3071                 rtm->rtm_type = RTN_LOCAL;
3072         else
3073                 rtm->rtm_type = RTN_UNICAST;
3074         rtm->rtm_flags = 0;
3075         if (!netif_carrier_ok(rt->dst.dev)) {
3076                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3077                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3078                         rtm->rtm_flags |= RTNH_F_DEAD;
3079         }
3080         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3081         rtm->rtm_protocol = rt->rt6i_protocol;
3082         if (rt->rt6i_flags & RTF_DYNAMIC)
3083                 rtm->rtm_protocol = RTPROT_REDIRECT;
3084         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3085                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3086                         rtm->rtm_protocol = RTPROT_RA;
3087                 else
3088                         rtm->rtm_protocol = RTPROT_KERNEL;
3089         }
3090
3091         if (rt->rt6i_flags & RTF_CACHE)
3092                 rtm->rtm_flags |= RTM_F_CLONED;
3093
3094         if (dst) {
3095                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3096                         goto nla_put_failure;
3097                 rtm->rtm_dst_len = 128;
3098         } else if (rtm->rtm_dst_len)
3099                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3100                         goto nla_put_failure;
3101 #ifdef CONFIG_IPV6_SUBTREES
3102         if (src) {
3103                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3104                         goto nla_put_failure;
3105                 rtm->rtm_src_len = 128;
3106         } else if (rtm->rtm_src_len &&
3107                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3108                 goto nla_put_failure;
3109 #endif
3110         if (iif) {
3111 #ifdef CONFIG_IPV6_MROUTE
3112                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3113                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3114                         if (err <= 0) {
3115                                 if (!nowait) {
3116                                         if (err == 0)
3117                                                 return 0;
3118                                         goto nla_put_failure;
3119                                 } else {
3120                                         if (err == -EMSGSIZE)
3121                                                 goto nla_put_failure;
3122                                 }
3123                         }
3124                 } else
3125 #endif
3126                         if (nla_put_u32(skb, RTA_IIF, iif))
3127                                 goto nla_put_failure;
3128         } else if (dst) {
3129                 struct in6_addr saddr_buf;
3130                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3131                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3132                         goto nla_put_failure;
3133         }
3134
3135         if (rt->rt6i_prefsrc.plen) {
3136                 struct in6_addr saddr_buf;
3137                 saddr_buf = rt->rt6i_prefsrc.addr;
3138                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3139                         goto nla_put_failure;
3140         }
3141
3142         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3143         if (rt->rt6i_pmtu)
3144                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3145         if (rtnetlink_put_metrics(skb, metrics) < 0)
3146                 goto nla_put_failure;
3147
3148         if (rt->rt6i_flags & RTF_GATEWAY) {
3149                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3150                         goto nla_put_failure;
3151         }
3152
3153         if (rt->dst.dev &&
3154             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3155                 goto nla_put_failure;
3156         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3157                 goto nla_put_failure;
3158
3159         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3160
3161         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3162                 goto nla_put_failure;
3163
3164         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3165                 goto nla_put_failure;
3166
3167         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3168
3169         nlmsg_end(skb, nlh);
3170         return 0;
3171
3172 nla_put_failure:
3173         nlmsg_cancel(skb, nlh);
3174         return -EMSGSIZE;
3175 }
3176
3177 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3178 {
3179         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3180         int prefix;
3181
3182         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3183                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3184                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3185         } else
3186                 prefix = 0;
3187
3188         return rt6_fill_node(arg->net,
3189                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3190                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3191                      prefix, 0, NLM_F_MULTI);
3192 }
3193
3194 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3195 {
3196         struct net *net = sock_net(in_skb->sk);
3197         struct nlattr *tb[RTA_MAX+1];
3198         struct rt6_info *rt;
3199         struct sk_buff *skb;
3200         struct rtmsg *rtm;
3201         struct flowi6 fl6;
3202         int err, iif = 0, oif = 0;
3203
3204         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3205         if (err < 0)
3206                 goto errout;
3207
3208         err = -EINVAL;
3209         memset(&fl6, 0, sizeof(fl6));
3210
3211         if (tb[RTA_SRC]) {
3212                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3213                         goto errout;
3214
3215                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3216         }
3217
3218         if (tb[RTA_DST]) {
3219                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3220                         goto errout;
3221
3222                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3223         }
3224
3225         if (tb[RTA_IIF])
3226                 iif = nla_get_u32(tb[RTA_IIF]);
3227
3228         if (tb[RTA_OIF])
3229                 oif = nla_get_u32(tb[RTA_OIF]);
3230
3231         if (tb[RTA_MARK])
3232                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3233
3234         if (iif) {
3235                 struct net_device *dev;
3236                 int flags = 0;
3237
3238                 dev = __dev_get_by_index(net, iif);
3239                 if (!dev) {
3240                         err = -ENODEV;
3241                         goto errout;
3242                 }
3243
3244                 fl6.flowi6_iif = iif;
3245
3246                 if (!ipv6_addr_any(&fl6.saddr))
3247                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3248
3249                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3250                                                                flags);
3251         } else {
3252                 fl6.flowi6_oif = oif;
3253
3254                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3255         }
3256
3257         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3258         if (!skb) {
3259                 ip6_rt_put(rt);
3260                 err = -ENOBUFS;
3261                 goto errout;
3262         }
3263
3264         /* Reserve room for dummy headers, this skb can pass
3265            through good chunk of routing engine.
3266          */
3267         skb_reset_mac_header(skb);
3268         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3269
3270         skb_dst_set(skb, &rt->dst);
3271
3272         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3273                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3274                             nlh->nlmsg_seq, 0, 0, 0);
3275         if (err < 0) {
3276                 kfree_skb(skb);
3277                 goto errout;
3278         }
3279
3280         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3281 errout:
3282         return err;
3283 }
3284
3285 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3286                      unsigned int nlm_flags)
3287 {
3288         struct sk_buff *skb;
3289         struct net *net = info->nl_net;
3290         u32 seq;
3291         int err;
3292
3293         err = -ENOBUFS;
3294         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3295
3296         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3297         if (!skb)
3298                 goto errout;
3299
3300         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3301                                 event, info->portid, seq, 0, 0, nlm_flags);
3302         if (err < 0) {
3303                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3304                 WARN_ON(err == -EMSGSIZE);
3305                 kfree_skb(skb);
3306                 goto errout;
3307         }
3308         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3309                     info->nlh, gfp_any());
3310         return;
3311 errout:
3312         if (err < 0)
3313                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3314 }
3315
3316 static int ip6_route_dev_notify(struct notifier_block *this,
3317                                 unsigned long event, void *ptr)
3318 {
3319         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3320         struct net *net = dev_net(dev);
3321
3322         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3323                 net->ipv6.ip6_null_entry->dst.dev = dev;
3324                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3325 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3326                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3327                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3328                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3329                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3330 #endif
3331         }
3332
3333         return NOTIFY_OK;
3334 }
3335
3336 /*
3337  *      /proc
3338  */
3339
3340 #ifdef CONFIG_PROC_FS
3341
3342 static const struct file_operations ipv6_route_proc_fops = {
3343         .owner          = THIS_MODULE,
3344         .open           = ipv6_route_open,
3345         .read           = seq_read,
3346         .llseek         = seq_lseek,
3347         .release        = seq_release_net,
3348 };
3349
3350 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3351 {
3352         struct net *net = (struct net *)seq->private;
3353         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3354                    net->ipv6.rt6_stats->fib_nodes,
3355                    net->ipv6.rt6_stats->fib_route_nodes,
3356                    net->ipv6.rt6_stats->fib_rt_alloc,
3357                    net->ipv6.rt6_stats->fib_rt_entries,
3358                    net->ipv6.rt6_stats->fib_rt_cache,
3359                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3360                    net->ipv6.rt6_stats->fib_discarded_routes);
3361
3362         return 0;
3363 }
3364
3365 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3366 {
3367         return single_open_net(inode, file, rt6_stats_seq_show);
3368 }
3369
3370 static const struct file_operations rt6_stats_seq_fops = {
3371         .owner   = THIS_MODULE,
3372         .open    = rt6_stats_seq_open,
3373         .read    = seq_read,
3374         .llseek  = seq_lseek,
3375         .release = single_release_net,
3376 };
3377 #endif  /* CONFIG_PROC_FS */
3378
3379 #ifdef CONFIG_SYSCTL
3380
3381 static
3382 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3383                               void __user *buffer, size_t *lenp, loff_t *ppos)
3384 {
3385         struct net *net;
3386         int delay;
3387         if (!write)
3388                 return -EINVAL;
3389
3390         net = (struct net *)ctl->extra1;
3391         delay = net->ipv6.sysctl.flush_delay;
3392         proc_dointvec(ctl, write, buffer, lenp, ppos);
3393         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3394         return 0;
3395 }
3396
3397 struct ctl_table ipv6_route_table_template[] = {
3398         {
3399                 .procname       =       "flush",
3400                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3401                 .maxlen         =       sizeof(int),
3402                 .mode           =       0200,
3403                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3404         },
3405         {
3406                 .procname       =       "gc_thresh",
3407                 .data           =       &ip6_dst_ops_template.gc_thresh,
3408                 .maxlen         =       sizeof(int),
3409                 .mode           =       0644,
3410                 .proc_handler   =       proc_dointvec,
3411         },
3412         {
3413                 .procname       =       "max_size",
3414                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3415                 .maxlen         =       sizeof(int),
3416                 .mode           =       0644,
3417                 .proc_handler   =       proc_dointvec,
3418         },
3419         {
3420                 .procname       =       "gc_min_interval",
3421                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3422                 .maxlen         =       sizeof(int),
3423                 .mode           =       0644,
3424                 .proc_handler   =       proc_dointvec_jiffies,
3425         },
3426         {
3427                 .procname       =       "gc_timeout",
3428                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3429                 .maxlen         =       sizeof(int),
3430                 .mode           =       0644,
3431                 .proc_handler   =       proc_dointvec_jiffies,
3432         },
3433         {
3434                 .procname       =       "gc_interval",
3435                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3436                 .maxlen         =       sizeof(int),
3437                 .mode           =       0644,
3438                 .proc_handler   =       proc_dointvec_jiffies,
3439         },
3440         {
3441                 .procname       =       "gc_elasticity",
3442                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3443                 .maxlen         =       sizeof(int),
3444                 .mode           =       0644,
3445                 .proc_handler   =       proc_dointvec,
3446         },
3447         {
3448                 .procname       =       "mtu_expires",
3449                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3450                 .maxlen         =       sizeof(int),
3451                 .mode           =       0644,
3452                 .proc_handler   =       proc_dointvec_jiffies,
3453         },
3454         {
3455                 .procname       =       "min_adv_mss",
3456                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3457                 .maxlen         =       sizeof(int),
3458                 .mode           =       0644,
3459                 .proc_handler   =       proc_dointvec,
3460         },
3461         {
3462                 .procname       =       "gc_min_interval_ms",
3463                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3464                 .maxlen         =       sizeof(int),
3465                 .mode           =       0644,
3466                 .proc_handler   =       proc_dointvec_ms_jiffies,
3467         },
3468         { }
3469 };
3470
3471 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3472 {
3473         struct ctl_table *table;
3474
3475         table = kmemdup(ipv6_route_table_template,
3476                         sizeof(ipv6_route_table_template),
3477                         GFP_KERNEL);
3478
3479         if (table) {
3480                 table[0].data = &net->ipv6.sysctl.flush_delay;
3481                 table[0].extra1 = net;
3482                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3483                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3484                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3485                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3486                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3487                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3488                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3489                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3490                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3491
3492                 /* Don't export sysctls to unprivileged users */
3493                 if (net->user_ns != &init_user_ns)
3494                         table[0].procname = NULL;
3495         }
3496
3497         return table;
3498 }
3499 #endif
3500
3501 static int __net_init ip6_route_net_init(struct net *net)
3502 {
3503         int ret = -ENOMEM;
3504
3505         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3506                sizeof(net->ipv6.ip6_dst_ops));
3507
3508         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3509                 goto out_ip6_dst_ops;
3510
3511         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3512                                            sizeof(*net->ipv6.ip6_null_entry),
3513                                            GFP_KERNEL);
3514         if (!net->ipv6.ip6_null_entry)
3515                 goto out_ip6_dst_entries;
3516         net->ipv6.ip6_null_entry->dst.path =
3517                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3518         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3519         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3520                          ip6_template_metrics, true);
3521
3522 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3523         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3524                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3525                                                GFP_KERNEL);
3526         if (!net->ipv6.ip6_prohibit_entry)
3527                 goto out_ip6_null_entry;
3528         net->ipv6.ip6_prohibit_entry->dst.path =
3529                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3530         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3531         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3532                          ip6_template_metrics, true);
3533
3534         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3535                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3536                                                GFP_KERNEL);
3537         if (!net->ipv6.ip6_blk_hole_entry)
3538                 goto out_ip6_prohibit_entry;
3539         net->ipv6.ip6_blk_hole_entry->dst.path =
3540                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3541         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3542         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3543                          ip6_template_metrics, true);
3544 #endif
3545
3546         net->ipv6.sysctl.flush_delay = 0;
3547         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3548         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3549         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3550         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3551         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3552         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3553         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3554
3555         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3556
3557         ret = 0;
3558 out:
3559         return ret;
3560
3561 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3562 out_ip6_prohibit_entry:
3563         kfree(net->ipv6.ip6_prohibit_entry);
3564 out_ip6_null_entry:
3565         kfree(net->ipv6.ip6_null_entry);
3566 #endif
3567 out_ip6_dst_entries:
3568         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3569 out_ip6_dst_ops:
3570         goto out;
3571 }
3572
3573 static void __net_exit ip6_route_net_exit(struct net *net)
3574 {
3575         kfree(net->ipv6.ip6_null_entry);
3576 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3577         kfree(net->ipv6.ip6_prohibit_entry);
3578         kfree(net->ipv6.ip6_blk_hole_entry);
3579 #endif
3580         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3581 }
3582
3583 static int __net_init ip6_route_net_init_late(struct net *net)
3584 {
3585 #ifdef CONFIG_PROC_FS
3586         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3587         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3588 #endif
3589         return 0;
3590 }
3591
3592 static void __net_exit ip6_route_net_exit_late(struct net *net)
3593 {
3594 #ifdef CONFIG_PROC_FS
3595         remove_proc_entry("ipv6_route", net->proc_net);
3596         remove_proc_entry("rt6_stats", net->proc_net);
3597 #endif
3598 }
3599
3600 static struct pernet_operations ip6_route_net_ops = {
3601         .init = ip6_route_net_init,
3602         .exit = ip6_route_net_exit,
3603 };
3604
3605 static int __net_init ipv6_inetpeer_init(struct net *net)
3606 {
3607         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3608
3609         if (!bp)
3610                 return -ENOMEM;
3611         inet_peer_base_init(bp);
3612         net->ipv6.peers = bp;
3613         return 0;
3614 }
3615
3616 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3617 {
3618         struct inet_peer_base *bp = net->ipv6.peers;
3619
3620         net->ipv6.peers = NULL;
3621         inetpeer_invalidate_tree(bp);
3622         kfree(bp);
3623 }
3624
3625 static struct pernet_operations ipv6_inetpeer_ops = {
3626         .init   =       ipv6_inetpeer_init,
3627         .exit   =       ipv6_inetpeer_exit,
3628 };
3629
3630 static struct pernet_operations ip6_route_net_late_ops = {
3631         .init = ip6_route_net_init_late,
3632         .exit = ip6_route_net_exit_late,
3633 };
3634
3635 static struct notifier_block ip6_route_dev_notifier = {
3636         .notifier_call = ip6_route_dev_notify,
3637         .priority = 0,
3638 };
3639
3640 int __init ip6_route_init(void)
3641 {
3642         int ret;
3643         int cpu;
3644
3645         ret = -ENOMEM;
3646         ip6_dst_ops_template.kmem_cachep =
3647                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3648                                   SLAB_HWCACHE_ALIGN, NULL);
3649         if (!ip6_dst_ops_template.kmem_cachep)
3650                 goto out;
3651
3652         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3653         if (ret)
3654                 goto out_kmem_cache;
3655
3656         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3657         if (ret)
3658                 goto out_dst_entries;
3659
3660         ret = register_pernet_subsys(&ip6_route_net_ops);
3661         if (ret)
3662                 goto out_register_inetpeer;
3663
3664         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3665
3666         /* Registering of the loopback is done before this portion of code,
3667          * the loopback reference in rt6_info will not be taken, do it
3668          * manually for init_net */
3669         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3670         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3671   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3672         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3673         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3674         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3675         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3676   #endif
3677         ret = fib6_init();
3678         if (ret)
3679                 goto out_register_subsys;
3680
3681         ret = xfrm6_init();
3682         if (ret)
3683                 goto out_fib6_init;
3684
3685         ret = fib6_rules_init();
3686         if (ret)
3687                 goto xfrm6_init;
3688
3689         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3690         if (ret)
3691                 goto fib6_rules_init;
3692
3693         ret = -ENOBUFS;
3694         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3695             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3696             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3697                 goto out_register_late_subsys;
3698
3699         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3700         if (ret)
3701                 goto out_register_late_subsys;
3702
3703         for_each_possible_cpu(cpu) {
3704                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3705
3706                 INIT_LIST_HEAD(&ul->head);
3707                 spin_lock_init(&ul->lock);
3708         }
3709
3710 out:
3711         return ret;
3712
3713 out_register_late_subsys:
3714         unregister_pernet_subsys(&ip6_route_net_late_ops);
3715 fib6_rules_init:
3716         fib6_rules_cleanup();
3717 xfrm6_init:
3718         xfrm6_fini();
3719 out_fib6_init:
3720         fib6_gc_cleanup();
3721 out_register_subsys:
3722         unregister_pernet_subsys(&ip6_route_net_ops);
3723 out_register_inetpeer:
3724         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3725 out_dst_entries:
3726         dst_entries_destroy(&ip6_dst_blackhole_ops);
3727 out_kmem_cache:
3728         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3729         goto out;
3730 }
3731
3732 void ip6_route_cleanup(void)
3733 {
3734         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3735         unregister_pernet_subsys(&ip6_route_net_late_ops);
3736         fib6_rules_cleanup();
3737         xfrm6_fini();
3738         fib6_gc_cleanup();
3739         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3740         unregister_pernet_subsys(&ip6_route_net_ops);
3741         dst_entries_destroy(&ip6_dst_blackhole_ops);
3742         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3743 }