net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64 #include <net/l3mdev.h>
  65
  66 #include <asm/uaccess.h>
  67
  68 #ifdef CONFIG_SYSCTL
  69 #include <linux/sysctl.h>
  70 #endif
  71
  72 enum rt6_nud_state {
  73         RT6_NUD_FAIL_HARD = -3,
  74         RT6_NUD_FAIL_PROBE = -2,
  75         RT6_NUD_FAIL_DO_RR = -1,
  76         RT6_NUD_SUCCEED = 1
  77 };
  78
  79 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  80 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  81 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  82 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  83 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  84 static void             ip6_dst_destroy(struct dst_entry *);
  85 static void             ip6_dst_ifdown(struct dst_entry *,
  86                                        struct net_device *dev, int how);
  87 static int               ip6_dst_gc(struct dst_ops *ops);
  88
  89 static int              ip6_pkt_discard(struct sk_buff *skb);
  90 static int              ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  91 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  92 static int              ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  93 static void             ip6_link_failure(struct sk_buff *skb);
  94 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  95                                            struct sk_buff *skb, u32 mtu);
  96 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  97                                         struct sk_buff *skb);
  98 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
  99 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
 100
 101 #ifdef CONFIG_IPV6_ROUTE_INFO
 102 static struct rt6_info *rt6_add_route_info(struct net *net,
 103                                            const struct in6_addr *prefix, int prefixlen,
 104                                            const struct in6_addr *gwaddr,
 105                                            struct net_device *dev,
 106                                            unsigned int pref);
 107 static struct rt6_info *rt6_get_route_info(struct net *net,
 108                                            const struct in6_addr *prefix, int prefixlen,
 109                                            const struct in6_addr *gwaddr,
 110                                            struct net_device *dev);
 111 #endif
 112
 113 struct uncached_list {
 114         spinlock_t              lock;
 115         struct list_head        head;
 116 };
 117
 118 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 119
 120 static void rt6_uncached_list_add(struct rt6_info *rt)
 121 {
 122         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 123
 124         rt->dst.flags |= DST_NOCACHE;
 125         rt->rt6i_uncached_list = ul;
 126
 127         spin_lock_bh(&ul->lock);
 128         list_add_tail(&rt->rt6i_uncached, &ul->head);
 129         spin_unlock_bh(&ul->lock);
 130 }
 131
 132 static void rt6_uncached_list_del(struct rt6_info *rt)
 133 {
 134         if (!list_empty(&rt->rt6i_uncached)) {
 135                 struct uncached_list *ul = rt->rt6i_uncached_list;
 136
 137                 spin_lock_bh(&ul->lock);
 138                 list_del(&rt->rt6i_uncached);
 139                 spin_unlock_bh(&ul->lock);
 140         }
 141 }
 142
 143 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 144 {
 145         struct net_device *loopback_dev = net->loopback_dev;
 146         int cpu;
 147
 148         if (dev == loopback_dev)
 149                 return;
 150
 151         for_each_possible_cpu(cpu) {
 152                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 153                 struct rt6_info *rt;
 154
 155                 spin_lock_bh(&ul->lock);
 156                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 157                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 158                         struct net_device *rt_dev = rt->dst.dev;
 159
 160                         if (rt_idev->dev == dev) {
 161                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 162                                 in6_dev_put(rt_idev);
 163                         }
 164
 165                         if (rt_dev == dev) {
 166                                 rt->dst.dev = loopback_dev;
 167                                 dev_hold(rt->dst.dev);
 168                                 dev_put(rt_dev);
 169                         }
 170                 }
 171                 spin_unlock_bh(&ul->lock);
 172         }
 173 }
 174
 175 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 176 {
 177         return dst_metrics_write_ptr(rt->dst.from);
 178 }
 179
 180 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 181 {
 182         struct rt6_info *rt = (struct rt6_info *)dst;
 183
 184         if (rt->rt6i_flags & RTF_PCPU)
 185                 return rt6_pcpu_cow_metrics(rt);
 186         else if (rt->rt6i_flags & RTF_CACHE)
 187                 return NULL;
 188         else
 189                 return dst_cow_metrics_generic(dst, old);
 190 }
 191
 192 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 193                                              struct sk_buff *skb,
 194                                              const void *daddr)
 195 {
 196         struct in6_addr *p = &rt->rt6i_gateway;
 197
 198         if (!ipv6_addr_any(p))
 199                 return (const void *) p;
 200         else if (skb)
 201                 return &ipv6_hdr(skb)->daddr;
 202         return daddr;
 203 }
 204
 205 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 206                                           struct sk_buff *skb,
 207                                           const void *daddr)
 208 {
 209         struct rt6_info *rt = (struct rt6_info *) dst;
 210         struct neighbour *n;
 211
 212         daddr = choose_neigh_daddr(rt, skb, daddr);
 213         n = __ipv6_neigh_lookup(dst->dev, daddr);
 214         if (n)
 215                 return n;
 216         return neigh_create(&nd_tbl, daddr, dst->dev);
 217 }
 218
 219 static struct dst_ops ip6_dst_ops_template = {
 220         .family                 =       AF_INET6,
 221         .gc                     =       ip6_dst_gc,
 222         .gc_thresh              =       1024,
 223         .check                  =       ip6_dst_check,
 224         .default_advmss         =       ip6_default_advmss,
 225         .mtu                    =       ip6_mtu,
 226         .cow_metrics            =       ipv6_cow_metrics,
 227         .destroy                =       ip6_dst_destroy,
 228         .ifdown                 =       ip6_dst_ifdown,
 229         .negative_advice        =       ip6_negative_advice,
 230         .link_failure           =       ip6_link_failure,
 231         .update_pmtu            =       ip6_rt_update_pmtu,
 232         .redirect               =       rt6_do_redirect,
 233         .local_out              =       __ip6_local_out,
 234         .neigh_lookup           =       ip6_neigh_lookup,
 235 };
 236
 237 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 238 {
 239         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 240
 241         return mtu ? : dst->dev->mtu;
 242 }
 243
 244 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 245                                          struct sk_buff *skb, u32 mtu)
 246 {
 247 }
 248
 249 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 250                                       struct sk_buff *skb)
 251 {
 252 }
 253
 254 static struct dst_ops ip6_dst_blackhole_ops = {
 255         .family                 =       AF_INET6,
 256         .destroy                =       ip6_dst_destroy,
 257         .check                  =       ip6_dst_check,
 258         .mtu                    =       ip6_blackhole_mtu,
 259         .default_advmss         =       ip6_default_advmss,
 260         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 261         .redirect               =       ip6_rt_blackhole_redirect,
 262         .cow_metrics            =       dst_cow_metrics_generic,
 263         .neigh_lookup           =       ip6_neigh_lookup,
 264 };
 265
 266 static const u32 ip6_template_metrics[RTAX_MAX] = {
 267         [RTAX_HOPLIMIT - 1] = 0,
 268 };
 269
 270 static const struct rt6_info ip6_null_entry_template = {
 271         .dst = {
 272                 .__refcnt       = ATOMIC_INIT(1),
 273                 .__use          = 1,
 274                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 275                 .error          = -ENETUNREACH,
 276                 .input          = ip6_pkt_discard,
 277                 .output         = ip6_pkt_discard_out,
 278         },
 279         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 280         .rt6i_protocol  = RTPROT_KERNEL,
 281         .rt6i_metric    = ~(u32) 0,
 282         .rt6i_ref       = ATOMIC_INIT(1),
 283 };
 284
 285 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 286
 287 static const struct rt6_info ip6_prohibit_entry_template = {
 288         .dst = {
 289                 .__refcnt       = ATOMIC_INIT(1),
 290                 .__use          = 1,
 291                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 292                 .error          = -EACCES,
 293                 .input          = ip6_pkt_prohibit,
 294                 .output         = ip6_pkt_prohibit_out,
 295         },
 296         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 297         .rt6i_protocol  = RTPROT_KERNEL,
 298         .rt6i_metric    = ~(u32) 0,
 299         .rt6i_ref       = ATOMIC_INIT(1),
 300 };
 301
 302 static const struct rt6_info ip6_blk_hole_entry_template = {
 303         .dst = {
 304                 .__refcnt       = ATOMIC_INIT(1),
 305                 .__use          = 1,
 306                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 307                 .error          = -EINVAL,
 308                 .input          = dst_discard,
 309                 .output         = dst_discard_out,
 310         },
 311         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 312         .rt6i_protocol  = RTPROT_KERNEL,
 313         .rt6i_metric    = ~(u32) 0,
 314         .rt6i_ref       = ATOMIC_INIT(1),
 315 };
 316
 317 #endif
 318
 319 static void rt6_info_init(struct rt6_info *rt)
 320 {
 321         struct dst_entry *dst = &rt->dst;
 322
 323         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 324         INIT_LIST_HEAD(&rt->rt6i_siblings);
 325         INIT_LIST_HEAD(&rt->rt6i_uncached);
 326 }
 327
 328 /* allocate dst with ip6_dst_ops */
 329 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 330                                         struct net_device *dev,
 331                                         int flags)
 332 {
 333         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 334                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 335
 336         if (rt)
 337                 rt6_info_init(rt);
 338
 339         return rt;
 340 }
 341
 342 struct rt6_info *ip6_dst_alloc(struct net *net,
 343                                struct net_device *dev,
 344                                int flags)
 345 {
 346         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 347
 348         if (rt) {
 349                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 350                 if (rt->rt6i_pcpu) {
 351                         int cpu;
 352
 353                         for_each_possible_cpu(cpu) {
 354                                 struct rt6_info **p;
 355
 356                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 357                                 /* no one shares rt */
 358                                 *p =  NULL;
 359                         }
 360                 } else {
 361                         dst_destroy((struct dst_entry *)rt);
 362                         return NULL;
 363                 }
 364         }
 365
 366         return rt;
 367 }
 368 EXPORT_SYMBOL(ip6_dst_alloc);
 369
 370 static void ip6_dst_destroy(struct dst_entry *dst)
 371 {
 372         struct rt6_info *rt = (struct rt6_info *)dst;
 373         struct dst_entry *from = dst->from;
 374         struct inet6_dev *idev;
 375
 376         dst_destroy_metrics_generic(dst);
 377         free_percpu(rt->rt6i_pcpu);
 378         rt6_uncached_list_del(rt);
 379
 380         idev = rt->rt6i_idev;
 381         if (idev) {
 382                 rt->rt6i_idev = NULL;
 383                 in6_dev_put(idev);
 384         }
 385
 386         dst->from = NULL;
 387         dst_release(from);
 388 }
 389
 390 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 391                            int how)
 392 {
 393         struct rt6_info *rt = (struct rt6_info *)dst;
 394         struct inet6_dev *idev = rt->rt6i_idev;
 395         struct net_device *loopback_dev =
 396                 dev_net(dev)->loopback_dev;
 397
 398         if (dev != loopback_dev) {
 399                 if (idev && idev->dev == dev) {
 400                         struct inet6_dev *loopback_idev =
 401                                 in6_dev_get(loopback_dev);
 402                         if (loopback_idev) {
 403                                 rt->rt6i_idev = loopback_idev;
 404                                 in6_dev_put(idev);
 405                         }
 406                 }
 407         }
 408 }
 409
 410 static bool __rt6_check_expired(const struct rt6_info *rt)
 411 {
 412         if (rt->rt6i_flags & RTF_EXPIRES)
 413                 return time_after(jiffies, rt->dst.expires);
 414         else
 415                 return false;
 416 }
 417
 418 static bool rt6_check_expired(const struct rt6_info *rt)
 419 {
 420         if (rt->rt6i_flags & RTF_EXPIRES) {
 421                 if (time_after(jiffies, rt->dst.expires))
 422                         return true;
 423         } else if (rt->dst.from) {
 424                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 425         }
 426         return false;
 427 }
 428
 429 /* Multipath route selection:
 430  *   Hash based function using packet header and flowlabel.
 431  * Adapted from fib_info_hashfn()
 432  */
 433 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 434                                const struct flowi6 *fl6)
 435 {
 436         return get_hash_from_flowi6(fl6) % candidate_count;
 437 }
 438
 439 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 440                                              struct flowi6 *fl6, int oif,
 441                                              int strict)
 442 {
 443         struct rt6_info *sibling, *next_sibling;
 444         int route_choosen;
 445
 446         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 447         /* Don't change the route, if route_choosen == 0
 448          * (siblings does not include ourself)
 449          */
 450         if (route_choosen)
 451                 list_for_each_entry_safe(sibling, next_sibling,
 452                                 &match->rt6i_siblings, rt6i_siblings) {
 453                         route_choosen--;
 454                         if (route_choosen == 0) {
 455                                 if (rt6_score_route(sibling, oif, strict) < 0)
 456                                         break;
 457                                 match = sibling;
 458                                 break;
 459                         }
 460                 }
 461         return match;
 462 }
 463
 464 /*
 465  *      Route lookup. Any table->tb6_lock is implied.
 466  */
 467
 468 static inline struct rt6_info *rt6_device_match(struct net *net,
 469                                                     struct rt6_info *rt,
 470                                                     const struct in6_addr *saddr,
 471                                                     int oif,
 472                                                     int flags)
 473 {
 474         struct rt6_info *local = NULL;
 475         struct rt6_info *sprt;
 476
 477         if (!oif && ipv6_addr_any(saddr))
 478                 goto out;
 479
 480         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 481                 struct net_device *dev = sprt->dst.dev;
 482
 483                 if (oif) {
 484                         if (dev->ifindex == oif)
 485                                 return sprt;
 486                         if (dev->flags & IFF_LOOPBACK) {
 487                                 if (!sprt->rt6i_idev ||
 488                                     sprt->rt6i_idev->dev->ifindex != oif) {
 489                                         if (flags & RT6_LOOKUP_F_IFACE)
 490                                                 continue;
 491                                         if (local &&
 492                                             local->rt6i_idev->dev->ifindex == oif)
 493                                                 continue;
 494                                 }
 495                                 local = sprt;
 496                         }
 497                 } else {
 498                         if (ipv6_chk_addr(net, saddr, dev,
 499                                           flags & RT6_LOOKUP_F_IFACE))
 500                                 return sprt;
 501                 }
 502         }
 503
 504         if (oif) {
 505                 if (local)
 506                         return local;
 507
 508                 if (flags & RT6_LOOKUP_F_IFACE)
 509                         return net->ipv6.ip6_null_entry;
 510         }
 511 out:
 512         return rt;
 513 }
 514
 515 #ifdef CONFIG_IPV6_ROUTER_PREF
 516 struct __rt6_probe_work {
 517         struct work_struct work;
 518         struct in6_addr target;
 519         struct net_device *dev;
 520 };
 521
 522 static void rt6_probe_deferred(struct work_struct *w)
 523 {
 524         struct in6_addr mcaddr;
 525         struct __rt6_probe_work *work =
 526                 container_of(w, struct __rt6_probe_work, work);
 527
 528         addrconf_addr_solict_mult(&work->target, &mcaddr);
 529         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL);
 530         dev_put(work->dev);
 531         kfree(work);
 532 }
 533
 534 static void rt6_probe(struct rt6_info *rt)
 535 {
 536         struct __rt6_probe_work *work;
 537         struct neighbour *neigh;
 538         /*
 539          * Okay, this does not seem to be appropriate
 540          * for now, however, we need to check if it
 541          * is really so; aka Router Reachability Probing.
 542          *
 543          * Router Reachability Probe MUST be rate-limited
 544          * to no more than one per minute.
 545          */
 546         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 547                 return;
 548         rcu_read_lock_bh();
 549         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 550         if (neigh) {
 551                 if (neigh->nud_state & NUD_VALID)
 552                         goto out;
 553
 554                 work = NULL;
 555                 write_lock(&neigh->lock);
 556                 if (!(neigh->nud_state & NUD_VALID) &&
 557                     time_after(jiffies,
 558                                neigh->updated +
 559                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 560                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 561                         if (work)
 562                                 __neigh_set_probe_once(neigh);
 563                 }
 564                 write_unlock(&neigh->lock);
 565         } else {
 566                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 567         }
 568
 569         if (work) {
 570                 INIT_WORK(&work->work, rt6_probe_deferred);
 571                 work->target = rt->rt6i_gateway;
 572                 dev_hold(rt->dst.dev);
 573                 work->dev = rt->dst.dev;
 574                 schedule_work(&work->work);
 575         }
 576
 577 out:
 578         rcu_read_unlock_bh();
 579 }
 580 #else
 581 static inline void rt6_probe(struct rt6_info *rt)
 582 {
 583 }
 584 #endif
 585
 586 /*
 587  * Default Router Selection (RFC 2461 6.3.6)
 588  */
 589 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 590 {
 591         struct net_device *dev = rt->dst.dev;
 592         if (!oif || dev->ifindex == oif)
 593                 return 2;
 594         if ((dev->flags & IFF_LOOPBACK) &&
 595             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 596                 return 1;
 597         return 0;
 598 }
 599
 600 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 601 {
 602         struct neighbour *neigh;
 603         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 604
 605         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 606             !(rt->rt6i_flags & RTF_GATEWAY))
 607                 return RT6_NUD_SUCCEED;
 608
 609         rcu_read_lock_bh();
 610         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 611         if (neigh) {
 612                 read_lock(&neigh->lock);
 613                 if (neigh->nud_state & NUD_VALID)
 614                         ret = RT6_NUD_SUCCEED;
 615 #ifdef CONFIG_IPV6_ROUTER_PREF
 616                 else if (!(neigh->nud_state & NUD_FAILED))
 617                         ret = RT6_NUD_SUCCEED;
 618                 else
 619                         ret = RT6_NUD_FAIL_PROBE;
 620 #endif
 621                 read_unlock(&neigh->lock);
 622         } else {
 623                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 624                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 625         }
 626         rcu_read_unlock_bh();
 627
 628         return ret;
 629 }
 630
 631 static int rt6_score_route(struct rt6_info *rt, int oif,
 632                            int strict)
 633 {
 634         int m;
 635
 636         m = rt6_check_dev(rt, oif);
 637         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 638                 return RT6_NUD_FAIL_HARD;
 639 #ifdef CONFIG_IPV6_ROUTER_PREF
 640         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 641 #endif
 642         if (strict & RT6_LOOKUP_F_REACHABLE) {
 643                 int n = rt6_check_neigh(rt);
 644                 if (n < 0)
 645                         return n;
 646         }
 647         return m;
 648 }
 649
 650 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 651                                    int *mpri, struct rt6_info *match,
 652                                    bool *do_rr)
 653 {
 654         int m;
 655         bool match_do_rr = false;
 656         struct inet6_dev *idev = rt->rt6i_idev;
 657         struct net_device *dev = rt->dst.dev;
 658
 659         if (dev && !netif_carrier_ok(dev) &&
 660             idev->cnf.ignore_routes_with_linkdown)
 661                 goto out;
 662
 663         if (rt6_check_expired(rt))
 664                 goto out;
 665
 666         m = rt6_score_route(rt, oif, strict);
 667         if (m == RT6_NUD_FAIL_DO_RR) {
 668                 match_do_rr = true;
 669                 m = 0; /* lowest valid score */
 670         } else if (m == RT6_NUD_FAIL_HARD) {
 671                 goto out;
 672         }
 673
 674         if (strict & RT6_LOOKUP_F_REACHABLE)
 675                 rt6_probe(rt);
 676
 677         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 678         if (m > *mpri) {
 679                 *do_rr = match_do_rr;
 680                 *mpri = m;
 681                 match = rt;
 682         }
 683 out:
 684         return match;
 685 }
 686
 687 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 688                                      struct rt6_info *rr_head,
 689                                      u32 metric, int oif, int strict,
 690                                      bool *do_rr)
 691 {
 692         struct rt6_info *rt, *match, *cont;
 693         int mpri = -1;
 694
 695         match = NULL;
 696         cont = NULL;
 697         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 698                 if (rt->rt6i_metric != metric) {
 699                         cont = rt;
 700                         break;
 701                 }
 702
 703                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 704         }
 705
 706         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 707                 if (rt->rt6i_metric != metric) {
 708                         cont = rt;
 709                         break;
 710                 }
 711
 712                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 713         }
 714
 715         if (match || !cont)
 716                 return match;
 717
 718         for (rt = cont; rt; rt = rt->dst.rt6_next)
 719                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 720
 721         return match;
 722 }
 723
 724 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 725 {
 726         struct rt6_info *match, *rt0;
 727         struct net *net;
 728         bool do_rr = false;
 729
 730         rt0 = fn->rr_ptr;
 731         if (!rt0)
 732                 fn->rr_ptr = rt0 = fn->leaf;
 733
 734         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 735                              &do_rr);
 736
 737         if (do_rr) {
 738                 struct rt6_info *next = rt0->dst.rt6_next;
 739
 740                 /* no entries matched; do round-robin */
 741                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 742                         next = fn->leaf;
 743
 744                 if (next != rt0)
 745                         fn->rr_ptr = next;
 746         }
 747
 748         net = dev_net(rt0->dst.dev);
 749         return match ? match : net->ipv6.ip6_null_entry;
 750 }
 751
 752 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 753 {
 754         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 755 }
 756
 757 #ifdef CONFIG_IPV6_ROUTE_INFO
 758 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 759                   const struct in6_addr *gwaddr)
 760 {
 761         struct net *net = dev_net(dev);
 762         struct route_info *rinfo = (struct route_info *) opt;
 763         struct in6_addr prefix_buf, *prefix;
 764         unsigned int pref;
 765         unsigned long lifetime;
 766         struct rt6_info *rt;
 767
 768         if (len < sizeof(struct route_info)) {
 769                 return -EINVAL;
 770         }
 771
 772         /* Sanity check for prefix_len and length */
 773         if (rinfo->length > 3) {
 774                 return -EINVAL;
 775         } else if (rinfo->prefix_len > 128) {
 776                 return -EINVAL;
 777         } else if (rinfo->prefix_len > 64) {
 778                 if (rinfo->length < 2) {
 779                         return -EINVAL;
 780                 }
 781         } else if (rinfo->prefix_len > 0) {
 782                 if (rinfo->length < 1) {
 783                         return -EINVAL;
 784                 }
 785         }
 786
 787         pref = rinfo->route_pref;
 788         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 789                 return -EINVAL;
 790
 791         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 792
 793         if (rinfo->length == 3)
 794                 prefix = (struct in6_addr *)rinfo->prefix;
 795         else {
 796                 /* this function is safe */
 797                 ipv6_addr_prefix(&prefix_buf,
 798                                  (struct in6_addr *)rinfo->prefix,
 799                                  rinfo->prefix_len);
 800                 prefix = &prefix_buf;
 801         }
 802
 803         if (rinfo->prefix_len == 0)
 804                 rt = rt6_get_dflt_router(gwaddr, dev);
 805         else
 806                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 807                                         gwaddr, dev);
 808
 809         if (rt && !lifetime) {
 810                 ip6_del_rt(rt);
 811                 rt = NULL;
 812         }
 813
 814         if (!rt && lifetime)
 815                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
 816                                         dev, pref);
 817         else if (rt)
 818                 rt->rt6i_flags = RTF_ROUTEINFO |
 819                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 820
 821         if (rt) {
 822                 if (!addrconf_finite_timeout(lifetime))
 823                         rt6_clean_expires(rt);
 824                 else
 825                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 826
 827                 ip6_rt_put(rt);
 828         }
 829         return 0;
 830 }
 831 #endif
 832
 833 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 834                                         struct in6_addr *saddr)
 835 {
 836         struct fib6_node *pn;
 837         while (1) {
 838                 if (fn->fn_flags & RTN_TL_ROOT)
 839                         return NULL;
 840                 pn = fn->parent;
 841                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 842                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 843                 else
 844                         fn = pn;
 845                 if (fn->fn_flags & RTN_RTINFO)
 846                         return fn;
 847         }
 848 }
 849
 850 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 851                                              struct fib6_table *table,
 852                                              struct flowi6 *fl6, int flags)
 853 {
 854         struct fib6_node *fn;
 855         struct rt6_info *rt;
 856
 857         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
 858                 flags &= ~RT6_LOOKUP_F_IFACE;
 859
 860         read_lock_bh(&table->tb6_lock);
 861         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 862 restart:
 863         rt = fn->leaf;
 864         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 865         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 866                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 867         if (rt == net->ipv6.ip6_null_entry) {
 868                 fn = fib6_backtrack(fn, &fl6->saddr);
 869                 if (fn)
 870                         goto restart;
 871         }
 872         dst_use(&rt->dst, jiffies);
 873         read_unlock_bh(&table->tb6_lock);
 874         return rt;
 875
 876 }
 877
 878 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 879                                     int flags)
 880 {
 881         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 882 }
 883 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 884
 885 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 886                             const struct in6_addr *saddr, int oif, int strict)
 887 {
 888         struct flowi6 fl6 = {
 889                 .flowi6_oif = oif,
 890                 .daddr = *daddr,
 891         };
 892         struct dst_entry *dst;
 893         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 894
 895         if (saddr) {
 896                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 897                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 898         }
 899
 900         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 901         if (dst->error == 0)
 902                 return (struct rt6_info *) dst;
 903
 904         dst_release(dst);
 905
 906         return NULL;
 907 }
 908 EXPORT_SYMBOL(rt6_lookup);
 909
 910 /* ip6_ins_rt is called with FREE table->tb6_lock.
 911    It takes new route entry, the addition fails by any reason the
 912    route is freed. In any case, if caller does not hold it, it may
 913    be destroyed.
 914  */
 915
 916 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 917                         struct mx6_config *mxc)
 918 {
 919         int err;
 920         struct fib6_table *table;
 921
 922         table = rt->rt6i_table;
 923         write_lock_bh(&table->tb6_lock);
 924         err = fib6_add(&table->tb6_root, rt, info, mxc);
 925         write_unlock_bh(&table->tb6_lock);
 926
 927         return err;
 928 }
 929
 930 int ip6_ins_rt(struct rt6_info *rt)
 931 {
 932         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 933         struct mx6_config mxc = { .mx = NULL, };
 934
 935         return __ip6_ins_rt(rt, &info, &mxc);
 936 }
 937
 938 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 939                                            const struct in6_addr *daddr,
 940                                            const struct in6_addr *saddr)
 941 {
 942         struct rt6_info *rt;
 943
 944         /*
 945          *      Clone the route.
 946          */
 947
 948         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 949                 ort = (struct rt6_info *)ort->dst.from;
 950
 951         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 952
 953         if (!rt)
 954                 return NULL;
 955
 956         ip6_rt_copy_init(rt, ort);
 957         rt->rt6i_flags |= RTF_CACHE;
 958         rt->rt6i_metric = 0;
 959         rt->dst.flags |= DST_HOST;
 960         rt->rt6i_dst.addr = *daddr;
 961         rt->rt6i_dst.plen = 128;
 962
 963         if (!rt6_is_gw_or_nonexthop(ort)) {
 964                 if (ort->rt6i_dst.plen != 128 &&
 965                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 966                         rt->rt6i_flags |= RTF_ANYCAST;
 967 #ifdef CONFIG_IPV6_SUBTREES
 968                 if (rt->rt6i_src.plen && saddr) {
 969                         rt->rt6i_src.addr = *saddr;
 970                         rt->rt6i_src.plen = 128;
 971                 }
 972 #endif
 973         }
 974
 975         return rt;
 976 }
 977
 978 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 979 {
 980         struct rt6_info *pcpu_rt;
 981
 982         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 983                                   rt->dst.dev, rt->dst.flags);
 984
 985         if (!pcpu_rt)
 986                 return NULL;
 987         ip6_rt_copy_init(pcpu_rt, rt);
 988         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 989         pcpu_rt->rt6i_flags |= RTF_PCPU;
 990         return pcpu_rt;
 991 }
 992
 993 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 994 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 995 {
 996         struct rt6_info *pcpu_rt, **p;
 997
 998         p = this_cpu_ptr(rt->rt6i_pcpu);
 999         pcpu_rt = *p;
1000
1001         if (pcpu_rt) {
1002                 dst_hold(&pcpu_rt->dst);
1003                 rt6_dst_from_metrics_check(pcpu_rt);
1004         }
1005         return pcpu_rt;
1006 }
1007
1008 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1009 {
1010         struct fib6_table *table = rt->rt6i_table;
1011         struct rt6_info *pcpu_rt, *prev, **p;
1012
1013         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1014         if (!pcpu_rt) {
1015                 struct net *net = dev_net(rt->dst.dev);
1016
1017                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1018                 return net->ipv6.ip6_null_entry;
1019         }
1020
1021         read_lock_bh(&table->tb6_lock);
1022         if (rt->rt6i_pcpu) {
1023                 p = this_cpu_ptr(rt->rt6i_pcpu);
1024                 prev = cmpxchg(p, NULL, pcpu_rt);
1025                 if (prev) {
1026                         /* If someone did it before us, return prev instead */
1027                         dst_destroy(&pcpu_rt->dst);
1028                         pcpu_rt = prev;
1029                 }
1030         } else {
1031                 /* rt has been removed from the fib6 tree
1032                  * before we have a chance to acquire the read_lock.
1033                  * In this case, don't brother to create a pcpu rt
1034                  * since rt is going away anyway.  The next
1035                  * dst_check() will trigger a re-lookup.
1036                  */
1037                 dst_destroy(&pcpu_rt->dst);
1038                 pcpu_rt = rt;
1039         }
1040         dst_hold(&pcpu_rt->dst);
1041         rt6_dst_from_metrics_check(pcpu_rt);
1042         read_unlock_bh(&table->tb6_lock);
1043         return pcpu_rt;
1044 }
1045
1046 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1047                                       struct flowi6 *fl6, int flags)
1048 {
1049         struct fib6_node *fn, *saved_fn;
1050         struct rt6_info *rt;
1051         int strict = 0;
1052
1053         strict |= flags & RT6_LOOKUP_F_IFACE;
1054         if (net->ipv6.devconf_all->forwarding == 0)
1055                 strict |= RT6_LOOKUP_F_REACHABLE;
1056
1057         read_lock_bh(&table->tb6_lock);
1058
1059         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1060         saved_fn = fn;
1061
1062         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1063                 oif = 0;
1064
1065 redo_rt6_select:
1066         rt = rt6_select(fn, oif, strict);
1067         if (rt->rt6i_nsiblings)
1068                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1069         if (rt == net->ipv6.ip6_null_entry) {
1070                 fn = fib6_backtrack(fn, &fl6->saddr);
1071                 if (fn)
1072                         goto redo_rt6_select;
1073                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1074                         /* also consider unreachable route */
1075                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1076                         fn = saved_fn;
1077                         goto redo_rt6_select;
1078                 }
1079         }
1080
1081
1082         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1083                 dst_use(&rt->dst, jiffies);
1084                 read_unlock_bh(&table->tb6_lock);
1085
1086                 rt6_dst_from_metrics_check(rt);
1087                 return rt;
1088         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1089                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1090                 /* Create a RTF_CACHE clone which will not be
1091                  * owned by the fib6 tree.  It is for the special case where
1092                  * the daddr in the skb during the neighbor look-up is different
1093                  * from the fl6->daddr used to look-up route here.
1094                  */
1095
1096                 struct rt6_info *uncached_rt;
1097
1098                 dst_use(&rt->dst, jiffies);
1099                 read_unlock_bh(&table->tb6_lock);
1100
1101                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1102                 dst_release(&rt->dst);
1103
1104                 if (uncached_rt)
1105                         rt6_uncached_list_add(uncached_rt);
1106                 else
1107                         uncached_rt = net->ipv6.ip6_null_entry;
1108
1109                 dst_hold(&uncached_rt->dst);
1110                 return uncached_rt;
1111
1112         } else {
1113                 /* Get a percpu copy */
1114
1115                 struct rt6_info *pcpu_rt;
1116
1117                 rt->dst.lastuse = jiffies;
1118                 rt->dst.__use++;
1119                 pcpu_rt = rt6_get_pcpu_route(rt);
1120
1121                 if (pcpu_rt) {
1122                         read_unlock_bh(&table->tb6_lock);
1123                 } else {
1124                         /* We have to do the read_unlock first
1125                          * because rt6_make_pcpu_route() may trigger
1126                          * ip6_dst_gc() which will take the write_lock.
1127                          */
1128                         dst_hold(&rt->dst);
1129                         read_unlock_bh(&table->tb6_lock);
1130                         pcpu_rt = rt6_make_pcpu_route(rt);
1131                         dst_release(&rt->dst);
1132                 }
1133
1134                 return pcpu_rt;
1135
1136         }
1137 }
1138
1139 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1140                                             struct flowi6 *fl6, int flags)
1141 {
1142         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1143 }
1144
1145 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1146                                                 struct net_device *dev,
1147                                                 struct flowi6 *fl6, int flags)
1148 {
1149         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1150                 flags |= RT6_LOOKUP_F_IFACE;
1151
1152         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1153 }
1154
1155 void ip6_route_input(struct sk_buff *skb)
1156 {
1157         const struct ipv6hdr *iph = ipv6_hdr(skb);
1158         struct net *net = dev_net(skb->dev);
1159         int flags = RT6_LOOKUP_F_HAS_SADDR;
1160         struct ip_tunnel_info *tun_info;
1161         struct flowi6 fl6 = {
1162                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1163                 .daddr = iph->daddr,
1164                 .saddr = iph->saddr,
1165                 .flowlabel = ip6_flowinfo(iph),
1166                 .flowi6_mark = skb->mark,
1167                 .flowi6_proto = iph->nexthdr,
1168         };
1169
1170         tun_info = skb_tunnel_info(skb);
1171         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1172                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1173         skb_dst_drop(skb);
1174         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1175 }
1176
1177 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1178                                              struct flowi6 *fl6, int flags)
1179 {
1180         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1181 }
1182
1183 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1184                                          struct flowi6 *fl6, int flags)
1185 {
1186         struct dst_entry *dst;
1187         bool any_src;
1188
1189         dst = l3mdev_rt6_dst_by_oif(net, fl6);
1190         if (dst)
1191                 return dst;
1192
1193         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1194
1195         any_src = ipv6_addr_any(&fl6->saddr);
1196         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1197             (fl6->flowi6_oif && any_src))
1198                 flags |= RT6_LOOKUP_F_IFACE;
1199
1200         if (!any_src)
1201                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1202         else if (sk)
1203                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1204
1205         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1206 }
1207 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1208
1209 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1210 {
1211         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1212         struct dst_entry *new = NULL;
1213
1214         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1215         if (rt) {
1216                 rt6_info_init(rt);
1217
1218                 new = &rt->dst;
1219                 new->__use = 1;
1220                 new->input = dst_discard;
1221                 new->output = dst_discard_out;
1222
1223                 dst_copy_metrics(new, &ort->dst);
1224                 rt->rt6i_idev = ort->rt6i_idev;
1225                 if (rt->rt6i_idev)
1226                         in6_dev_hold(rt->rt6i_idev);
1227
1228                 rt->rt6i_gateway = ort->rt6i_gateway;
1229                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1230                 rt->rt6i_metric = 0;
1231
1232                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1233 #ifdef CONFIG_IPV6_SUBTREES
1234                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1235 #endif
1236
1237                 dst_free(new);
1238         }
1239
1240         dst_release(dst_orig);
1241         return new ? new : ERR_PTR(-ENOMEM);
1242 }
1243
1244 /*
1245  *      Destination cache support functions
1246  */
1247
1248 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1249 {
1250         if (rt->dst.from &&
1251             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1252                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1253 }
1254
1255 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1256 {
1257         u32 rt_cookie;
1258
1259         if (!rt6_get_cookie_safe(rt, &rt_cookie) || rt_cookie != cookie)
1260                 return NULL;
1261
1262         if (rt6_check_expired(rt))
1263                 return NULL;
1264
1265         return &rt->dst;
1266 }
1267
1268 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1269 {
1270         if (!__rt6_check_expired(rt) &&
1271             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1272             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1273                 return &rt->dst;
1274         else
1275                 return NULL;
1276 }
1277
1278 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1279 {
1280         struct rt6_info *rt;
1281
1282         rt = (struct rt6_info *) dst;
1283
1284         /* All IPV6 dsts are created with ->obsolete set to the value
1285          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1286          * into this function always.
1287          */
1288
1289         rt6_dst_from_metrics_check(rt);
1290
1291         if (rt->rt6i_flags & RTF_PCPU ||
1292             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1293                 return rt6_dst_from_check(rt, cookie);
1294         else
1295                 return rt6_check(rt, cookie);
1296 }
1297
1298 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1299 {
1300         struct rt6_info *rt = (struct rt6_info *) dst;
1301
1302         if (rt) {
1303                 if (rt->rt6i_flags & RTF_CACHE) {
1304                         if (rt6_check_expired(rt)) {
1305                                 ip6_del_rt(rt);
1306                                 dst = NULL;
1307                         }
1308                 } else {
1309                         dst_release(dst);
1310                         dst = NULL;
1311                 }
1312         }
1313         return dst;
1314 }
1315
1316 static void ip6_link_failure(struct sk_buff *skb)
1317 {
1318         struct rt6_info *rt;
1319
1320         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1321
1322         rt = (struct rt6_info *) skb_dst(skb);
1323         if (rt) {
1324                 if (rt->rt6i_flags & RTF_CACHE) {
1325                         dst_hold(&rt->dst);
1326                         ip6_del_rt(rt);
1327                 } else {
1328                         struct fib6_node *fn;
1329
1330                         rcu_read_lock();
1331                         fn = rcu_dereference(rt->rt6i_node);
1332                         if (fn && (rt->rt6i_flags & RTF_DEFAULT))
1333                                 fn->fn_sernum = -1;
1334                         rcu_read_unlock();
1335                 }
1336         }
1337 }
1338
1339 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1340 {
1341         struct net *net = dev_net(rt->dst.dev);
1342
1343         rt->rt6i_flags |= RTF_MODIFIED;
1344         rt->rt6i_pmtu = mtu;
1345         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1346 }
1347
1348 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1349 {
1350         return !(rt->rt6i_flags & RTF_CACHE) &&
1351                 (rt->rt6i_flags & RTF_PCPU ||
1352                  rcu_access_pointer(rt->rt6i_node));
1353 }
1354
1355 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1356                                  const struct ipv6hdr *iph, u32 mtu)
1357 {
1358         struct rt6_info *rt6 = (struct rt6_info *)dst;
1359
1360         if (rt6->rt6i_flags & RTF_LOCAL)
1361                 return;
1362
1363         dst_confirm(dst);
1364         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1365         if (mtu >= dst_mtu(dst))
1366                 return;
1367
1368         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1369                 rt6_do_update_pmtu(rt6, mtu);
1370         } else {
1371                 const struct in6_addr *daddr, *saddr;
1372                 struct rt6_info *nrt6;
1373
1374                 if (iph) {
1375                         daddr = &iph->daddr;
1376                         saddr = &iph->saddr;
1377                 } else if (sk) {
1378                         daddr = &sk->sk_v6_daddr;
1379                         saddr = &inet6_sk(sk)->saddr;
1380                 } else {
1381                         return;
1382                 }
1383                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1384                 if (nrt6) {
1385                         rt6_do_update_pmtu(nrt6, mtu);
1386
1387                         /* ip6_ins_rt(nrt6) will bump the
1388                          * rt6->rt6i_node->fn_sernum
1389                          * which will fail the next rt6_check() and
1390                          * invalidate the sk->sk_dst_cache.
1391                          */
1392                         ip6_ins_rt(nrt6);
1393                 }
1394         }
1395 }
1396
1397 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1398                                struct sk_buff *skb, u32 mtu)
1399 {
1400         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1401 }
1402
1403 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1404                      int oif, u32 mark)
1405 {
1406         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1407         struct dst_entry *dst;
1408         struct flowi6 fl6;
1409
1410         memset(&fl6, 0, sizeof(fl6));
1411         fl6.flowi6_oif = oif;
1412         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1413         fl6.daddr = iph->daddr;
1414         fl6.saddr = iph->saddr;
1415         fl6.flowlabel = ip6_flowinfo(iph);
1416
1417         dst = ip6_route_output(net, NULL, &fl6);
1418         if (!dst->error)
1419                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1420         dst_release(dst);
1421 }
1422 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1423
1424 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1425 {
1426         int oif = sk->sk_bound_dev_if;
1427
1428         if (!oif && skb->dev)
1429                 oif = l3mdev_master_ifindex(skb->dev);
1430
1431         ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark);
1432 }
1433 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1434
1435 /* Handle redirects */
1436 struct ip6rd_flowi {
1437         struct flowi6 fl6;
1438         struct in6_addr gateway;
1439 };
1440
1441 static struct rt6_info *__ip6_route_redirect(struct net *net,
1442                                              struct fib6_table *table,
1443                                              struct flowi6 *fl6,
1444                                              int flags)
1445 {
1446         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1447         struct rt6_info *rt;
1448         struct fib6_node *fn;
1449
1450         /* Get the "current" route for this destination and
1451          * check if the redirect has come from approriate router.
1452          *
1453          * RFC 4861 specifies that redirects should only be
1454          * accepted if they come from the nexthop to the target.
1455          * Due to the way the routes are chosen, this notion
1456          * is a bit fuzzy and one might need to check all possible
1457          * routes.
1458          */
1459
1460         read_lock_bh(&table->tb6_lock);
1461         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1462 restart:
1463         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1464                 if (rt6_check_expired(rt))
1465                         continue;
1466                 if (rt->dst.error)
1467                         break;
1468                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1469                         continue;
1470                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1471                         continue;
1472                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1473                         continue;
1474                 break;
1475         }
1476
1477         if (!rt)
1478                 rt = net->ipv6.ip6_null_entry;
1479         else if (rt->dst.error) {
1480                 rt = net->ipv6.ip6_null_entry;
1481                 goto out;
1482         }
1483
1484         if (rt == net->ipv6.ip6_null_entry) {
1485                 fn = fib6_backtrack(fn, &fl6->saddr);
1486                 if (fn)
1487                         goto restart;
1488         }
1489
1490 out:
1491         dst_hold(&rt->dst);
1492
1493         read_unlock_bh(&table->tb6_lock);
1494
1495         return rt;
1496 };
1497
1498 static struct dst_entry *ip6_route_redirect(struct net *net,
1499                                         const struct flowi6 *fl6,
1500                                         const struct in6_addr *gateway)
1501 {
1502         int flags = RT6_LOOKUP_F_HAS_SADDR;
1503         struct ip6rd_flowi rdfl;
1504
1505         rdfl.fl6 = *fl6;
1506         rdfl.gateway = *gateway;
1507
1508         return fib6_rule_lookup(net, &rdfl.fl6,
1509                                 flags, __ip6_route_redirect);
1510 }
1511
1512 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1513 {
1514         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1515         struct dst_entry *dst;
1516         struct flowi6 fl6;
1517
1518         memset(&fl6, 0, sizeof(fl6));
1519         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1520         fl6.flowi6_oif = oif;
1521         fl6.flowi6_mark = mark;
1522         fl6.daddr = iph->daddr;
1523         fl6.saddr = iph->saddr;
1524         fl6.flowlabel = ip6_flowinfo(iph);
1525
1526         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1527         rt6_do_redirect(dst, NULL, skb);
1528         dst_release(dst);
1529 }
1530 EXPORT_SYMBOL_GPL(ip6_redirect);
1531
1532 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1533                             u32 mark)
1534 {
1535         const struct ipv6hdr *iph = ipv6_hdr(skb);
1536         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1537         struct dst_entry *dst;
1538         struct flowi6 fl6;
1539
1540         memset(&fl6, 0, sizeof(fl6));
1541         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1542         fl6.flowi6_oif = oif;
1543         fl6.flowi6_mark = mark;
1544         fl6.daddr = msg->dest;
1545         fl6.saddr = iph->daddr;
1546
1547         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1548         rt6_do_redirect(dst, NULL, skb);
1549         dst_release(dst);
1550 }
1551
1552 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1553 {
1554         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1555 }
1556 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1557
1558 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1559 {
1560         struct net_device *dev = dst->dev;
1561         unsigned int mtu = dst_mtu(dst);
1562         struct net *net = dev_net(dev);
1563
1564         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1565
1566         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1567                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1568
1569         /*
1570          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1571          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1572          * IPV6_MAXPLEN is also valid and means: "any MSS,
1573          * rely only on pmtu discovery"
1574          */
1575         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1576                 mtu = IPV6_MAXPLEN;
1577         return mtu;
1578 }
1579
1580 static unsigned int ip6_mtu(const struct dst_entry *dst)
1581 {
1582         const struct rt6_info *rt = (const struct rt6_info *)dst;
1583         unsigned int mtu = rt->rt6i_pmtu;
1584         struct inet6_dev *idev;
1585
1586         if (mtu)
1587                 goto out;
1588
1589         mtu = dst_metric_raw(dst, RTAX_MTU);
1590         if (mtu)
1591                 goto out;
1592
1593         mtu = IPV6_MIN_MTU;
1594
1595         rcu_read_lock();
1596         idev = __in6_dev_get(dst->dev);
1597         if (idev)
1598                 mtu = idev->cnf.mtu6;
1599         rcu_read_unlock();
1600
1601 out:
1602         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1603 }
1604
1605 static struct dst_entry *icmp6_dst_gc_list;
1606 static DEFINE_SPINLOCK(icmp6_dst_lock);
1607
1608 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1609                                   struct flowi6 *fl6)
1610 {
1611         struct dst_entry *dst;
1612         struct rt6_info *rt;
1613         struct inet6_dev *idev = in6_dev_get(dev);
1614         struct net *net = dev_net(dev);
1615
1616         if (unlikely(!idev))
1617                 return ERR_PTR(-ENODEV);
1618
1619         rt = ip6_dst_alloc(net, dev, 0);
1620         if (unlikely(!rt)) {
1621                 in6_dev_put(idev);
1622                 dst = ERR_PTR(-ENOMEM);
1623                 goto out;
1624         }
1625
1626         rt->dst.flags |= DST_HOST;
1627         rt->dst.input = ip6_input;
1628         rt->dst.output  = ip6_output;
1629         atomic_set(&rt->dst.__refcnt, 1);
1630         rt->rt6i_gateway  = fl6->daddr;
1631         rt->rt6i_dst.addr = fl6->daddr;
1632         rt->rt6i_dst.plen = 128;
1633         rt->rt6i_idev     = idev;
1634         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1635
1636         spin_lock_bh(&icmp6_dst_lock);
1637         rt->dst.next = icmp6_dst_gc_list;
1638         icmp6_dst_gc_list = &rt->dst;
1639         spin_unlock_bh(&icmp6_dst_lock);
1640
1641         fib6_force_start_gc(net);
1642
1643         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1644
1645 out:
1646         return dst;
1647 }
1648
1649 int icmp6_dst_gc(void)
1650 {
1651         struct dst_entry *dst, **pprev;
1652         int more = 0;
1653
1654         spin_lock_bh(&icmp6_dst_lock);
1655         pprev = &icmp6_dst_gc_list;
1656
1657         while ((dst = *pprev) != NULL) {
1658                 if (!atomic_read(&dst->__refcnt)) {
1659                         *pprev = dst->next;
1660                         dst_free(dst);
1661                 } else {
1662                         pprev = &dst->next;
1663                         ++more;
1664                 }
1665         }
1666
1667         spin_unlock_bh(&icmp6_dst_lock);
1668
1669         return more;
1670 }
1671
1672 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1673                             void *arg)
1674 {
1675         struct dst_entry *dst, **pprev;
1676
1677         spin_lock_bh(&icmp6_dst_lock);
1678         pprev = &icmp6_dst_gc_list;
1679         while ((dst = *pprev) != NULL) {
1680                 struct rt6_info *rt = (struct rt6_info *) dst;
1681                 if (func(rt, arg)) {
1682                         *pprev = dst->next;
1683                         dst_free(dst);
1684                 } else {
1685                         pprev = &dst->next;
1686                 }
1687         }
1688         spin_unlock_bh(&icmp6_dst_lock);
1689 }
1690
1691 static int ip6_dst_gc(struct dst_ops *ops)
1692 {
1693         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1694         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1695         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1696         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1697         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1698         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1699         int entries;
1700
1701         entries = dst_entries_get_fast(ops);
1702         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1703             entries <= rt_max_size)
1704                 goto out;
1705
1706         net->ipv6.ip6_rt_gc_expire++;
1707         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1708         entries = dst_entries_get_slow(ops);
1709         if (entries < ops->gc_thresh)
1710                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1711 out:
1712         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1713         return entries > rt_max_size;
1714 }
1715
1716 static int ip6_convert_metrics(struct mx6_config *mxc,
1717                                const struct fib6_config *cfg)
1718 {
1719         bool ecn_ca = false;
1720         struct nlattr *nla;
1721         int remaining;
1722         u32 *mp;
1723
1724         if (!cfg->fc_mx)
1725                 return 0;
1726
1727         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1728         if (unlikely(!mp))
1729                 return -ENOMEM;
1730
1731         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1732                 int type = nla_type(nla);
1733                 u32 val;
1734
1735                 if (!type)
1736                         continue;
1737                 if (unlikely(type > RTAX_MAX))
1738                         goto err;
1739
1740                 if (type == RTAX_CC_ALGO) {
1741                         char tmp[TCP_CA_NAME_MAX];
1742
1743                         nla_strlcpy(tmp, nla, sizeof(tmp));
1744                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1745                         if (val == TCP_CA_UNSPEC)
1746                                 goto err;
1747                 } else {
1748                         val = nla_get_u32(nla);
1749                 }
1750                 if (type == RTAX_HOPLIMIT && val > 255)
1751                         val = 255;
1752                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1753                         goto err;
1754
1755                 mp[type - 1] = val;
1756                 __set_bit(type - 1, mxc->mx_valid);
1757         }
1758
1759         if (ecn_ca) {
1760                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1761                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1762         }
1763
1764         mxc->mx = mp;
1765         return 0;
1766  err:
1767         kfree(mp);
1768         return -EINVAL;
1769 }
1770
1771 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1772 {
1773         struct net *net = cfg->fc_nlinfo.nl_net;
1774         struct rt6_info *rt = NULL;
1775         struct net_device *dev = NULL;
1776         struct inet6_dev *idev = NULL;
1777         struct fib6_table *table;
1778         int addr_type;
1779         int err = -EINVAL;
1780
1781         /* RTF_PCPU is an internal flag; can not be set by userspace */
1782         if (cfg->fc_flags & RTF_PCPU)
1783                 goto out;
1784
1785         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1786                 goto out;
1787 #ifndef CONFIG_IPV6_SUBTREES
1788         if (cfg->fc_src_len)
1789                 goto out;
1790 #endif
1791         if (cfg->fc_ifindex) {
1792                 err = -ENODEV;
1793                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1794                 if (!dev)
1795                         goto out;
1796                 idev = in6_dev_get(dev);
1797                 if (!idev)
1798                         goto out;
1799         }
1800
1801         if (cfg->fc_metric == 0)
1802                 cfg->fc_metric = IP6_RT_PRIO_USER;
1803
1804         err = -ENOBUFS;
1805         if (cfg->fc_nlinfo.nlh &&
1806             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1807                 table = fib6_get_table(net, cfg->fc_table);
1808                 if (!table) {
1809                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1810                         table = fib6_new_table(net, cfg->fc_table);
1811                 }
1812         } else {
1813                 table = fib6_new_table(net, cfg->fc_table);
1814         }
1815
1816         if (!table)
1817                 goto out;
1818
1819         rt = ip6_dst_alloc(net, NULL,
1820                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1821
1822         if (!rt) {
1823                 err = -ENOMEM;
1824                 goto out;
1825         }
1826
1827         if (cfg->fc_flags & RTF_EXPIRES)
1828                 rt6_set_expires(rt, jiffies +
1829                                 clock_t_to_jiffies(cfg->fc_expires));
1830         else
1831                 rt6_clean_expires(rt);
1832
1833         if (cfg->fc_protocol == RTPROT_UNSPEC)
1834                 cfg->fc_protocol = RTPROT_BOOT;
1835         rt->rt6i_protocol = cfg->fc_protocol;
1836
1837         addr_type = ipv6_addr_type(&cfg->fc_dst);
1838
1839         if (addr_type & IPV6_ADDR_MULTICAST)
1840                 rt->dst.input = ip6_mc_input;
1841         else if (cfg->fc_flags & RTF_LOCAL)
1842                 rt->dst.input = ip6_input;
1843         else
1844                 rt->dst.input = ip6_forward;
1845
1846         rt->dst.output = ip6_output;
1847
1848         if (cfg->fc_encap) {
1849                 struct lwtunnel_state *lwtstate;
1850
1851                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1852                                            cfg->fc_encap, AF_INET6, cfg,
1853                                            &lwtstate);
1854                 if (err)
1855                         goto out;
1856                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1857                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1858                         rt->dst.lwtstate->orig_output = rt->dst.output;
1859                         rt->dst.output = lwtunnel_output;
1860                 }
1861                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1862                         rt->dst.lwtstate->orig_input = rt->dst.input;
1863                         rt->dst.input = lwtunnel_input;
1864                 }
1865         }
1866
1867         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1868         rt->rt6i_dst.plen = cfg->fc_dst_len;
1869         if (rt->rt6i_dst.plen == 128)
1870                 rt->dst.flags |= DST_HOST;
1871
1872 #ifdef CONFIG_IPV6_SUBTREES
1873         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1874         rt->rt6i_src.plen = cfg->fc_src_len;
1875 #endif
1876
1877         rt->rt6i_metric = cfg->fc_metric;
1878
1879         /* We cannot add true routes via loopback here,
1880            they would result in kernel looping; promote them to reject routes
1881          */
1882         if ((cfg->fc_flags & RTF_REJECT) ||
1883             (dev && (dev->flags & IFF_LOOPBACK) &&
1884              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1885              !(cfg->fc_flags & RTF_LOCAL))) {
1886                 /* hold loopback dev/idev if we haven't done so. */
1887                 if (dev != net->loopback_dev) {
1888                         if (dev) {
1889                                 dev_put(dev);
1890                                 in6_dev_put(idev);
1891                         }
1892                         dev = net->loopback_dev;
1893                         dev_hold(dev);
1894                         idev = in6_dev_get(dev);
1895                         if (!idev) {
1896                                 err = -ENODEV;
1897                                 goto out;
1898                         }
1899                 }
1900                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1901                 switch (cfg->fc_type) {
1902                 case RTN_BLACKHOLE:
1903                         rt->dst.error = -EINVAL;
1904                         rt->dst.output = dst_discard_out;
1905                         rt->dst.input = dst_discard;
1906                         break;
1907                 case RTN_PROHIBIT:
1908                         rt->dst.error = -EACCES;
1909                         rt->dst.output = ip6_pkt_prohibit_out;
1910                         rt->dst.input = ip6_pkt_prohibit;
1911                         break;
1912                 case RTN_THROW:
1913                 case RTN_UNREACHABLE:
1914                 default:
1915                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1916                                         : (cfg->fc_type == RTN_UNREACHABLE)
1917                                         ? -EHOSTUNREACH : -ENETUNREACH;
1918                         rt->dst.output = ip6_pkt_discard_out;
1919                         rt->dst.input = ip6_pkt_discard;
1920                         break;
1921                 }
1922                 goto install_route;
1923         }
1924
1925         if (cfg->fc_flags & RTF_GATEWAY) {
1926                 const struct in6_addr *gw_addr;
1927                 int gwa_type;
1928
1929                 gw_addr = &cfg->fc_gateway;
1930                 gwa_type = ipv6_addr_type(gw_addr);
1931
1932                 /* if gw_addr is local we will fail to detect this in case
1933                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1934                  * will return already-added prefix route via interface that
1935                  * prefix route was assigned to, which might be non-loopback.
1936                  */
1937                 err = -EINVAL;
1938                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1939                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1940                                             dev : NULL, 0, 0))
1941                         goto out;
1942
1943                 rt->rt6i_gateway = *gw_addr;
1944
1945                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1946                         struct rt6_info *grt;
1947
1948                         /* IPv6 strictly inhibits using not link-local
1949                            addresses as nexthop address.
1950                            Otherwise, router will not able to send redirects.
1951                            It is very good, but in some (rare!) circumstances
1952                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1953                            some exceptions. --ANK
1954                          */
1955                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1956                                 goto out;
1957
1958                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1959
1960                         err = -EHOSTUNREACH;
1961                         if (!grt)
1962                                 goto out;
1963                         if (dev) {
1964                                 if (dev != grt->dst.dev) {
1965                                         ip6_rt_put(grt);
1966                                         goto out;
1967                                 }
1968                         } else {
1969                                 dev = grt->dst.dev;
1970                                 idev = grt->rt6i_idev;
1971                                 dev_hold(dev);
1972                                 in6_dev_hold(grt->rt6i_idev);
1973                         }
1974                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1975                                 err = 0;
1976                         ip6_rt_put(grt);
1977
1978                         if (err)
1979                                 goto out;
1980                 }
1981                 err = -EINVAL;
1982                 if (!dev || (dev->flags & IFF_LOOPBACK))
1983                         goto out;
1984         }
1985
1986         err = -ENODEV;
1987         if (!dev)
1988                 goto out;
1989
1990         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1991                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1992                         err = -EINVAL;
1993                         goto out;
1994                 }
1995                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1996                 rt->rt6i_prefsrc.plen = 128;
1997         } else
1998                 rt->rt6i_prefsrc.plen = 0;
1999
2000         rt->rt6i_flags = cfg->fc_flags;
2001
2002 install_route:
2003         rt->dst.dev = dev;
2004         rt->rt6i_idev = idev;
2005         rt->rt6i_table = table;
2006
2007         cfg->fc_nlinfo.nl_net = dev_net(dev);
2008
2009         return rt;
2010 out:
2011         if (dev)
2012                 dev_put(dev);
2013         if (idev)
2014                 in6_dev_put(idev);
2015         if (rt)
2016                 dst_free(&rt->dst);
2017
2018         return ERR_PTR(err);
2019 }
2020
2021 int ip6_route_add(struct fib6_config *cfg)
2022 {
2023         struct mx6_config mxc = { .mx = NULL, };
2024         struct rt6_info *rt;
2025         int err;
2026
2027         rt = ip6_route_info_create(cfg);
2028         if (IS_ERR(rt)) {
2029                 err = PTR_ERR(rt);
2030                 rt = NULL;
2031                 goto out;
2032         }
2033
2034         err = ip6_convert_metrics(&mxc, cfg);
2035         if (err)
2036                 goto out;
2037
2038         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2039
2040         kfree(mxc.mx);
2041
2042         return err;
2043 out:
2044         if (rt)
2045                 dst_free(&rt->dst);
2046
2047         return err;
2048 }
2049
2050 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2051 {
2052         int err;
2053         struct fib6_table *table;
2054         struct net *net = dev_net(rt->dst.dev);
2055
2056         if (rt == net->ipv6.ip6_null_entry ||
2057             rt->dst.flags & DST_NOCACHE) {
2058                 err = -ENOENT;
2059                 goto out;
2060         }
2061
2062         table = rt->rt6i_table;
2063         write_lock_bh(&table->tb6_lock);
2064         err = fib6_del(rt, info);
2065         write_unlock_bh(&table->tb6_lock);
2066
2067 out:
2068         ip6_rt_put(rt);
2069         return err;
2070 }
2071
2072 int ip6_del_rt(struct rt6_info *rt)
2073 {
2074         struct nl_info info = {
2075                 .nl_net = dev_net(rt->dst.dev),
2076         };
2077         return __ip6_del_rt(rt, &info);
2078 }
2079
2080 static int ip6_route_del(struct fib6_config *cfg)
2081 {
2082         struct fib6_table *table;
2083         struct fib6_node *fn;
2084         struct rt6_info *rt;
2085         int err = -ESRCH;
2086
2087         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2088         if (!table)
2089                 return err;
2090
2091         read_lock_bh(&table->tb6_lock);
2092
2093         fn = fib6_locate(&table->tb6_root,
2094                          &cfg->fc_dst, cfg->fc_dst_len,
2095                          &cfg->fc_src, cfg->fc_src_len);
2096
2097         if (fn) {
2098                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2099                         if ((rt->rt6i_flags & RTF_CACHE) &&
2100                             !(cfg->fc_flags & RTF_CACHE))
2101                                 continue;
2102                         if (cfg->fc_ifindex &&
2103                             (!rt->dst.dev ||
2104                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2105                                 continue;
2106                         if (cfg->fc_flags & RTF_GATEWAY &&
2107                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2108                                 continue;
2109                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2110                                 continue;
2111                         if (cfg->fc_protocol && cfg->fc_protocol != rt->rt6i_protocol)
2112                                 continue;
2113                         dst_hold(&rt->dst);
2114                         read_unlock_bh(&table->tb6_lock);
2115
2116                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2117                 }
2118         }
2119         read_unlock_bh(&table->tb6_lock);
2120
2121         return err;
2122 }
2123
2124 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2125 {
2126         struct netevent_redirect netevent;
2127         struct rt6_info *rt, *nrt = NULL;
2128         struct ndisc_options ndopts;
2129         struct inet6_dev *in6_dev;
2130         struct neighbour *neigh;
2131         struct rd_msg *msg;
2132         int optlen, on_link;
2133         u8 *lladdr;
2134
2135         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2136         optlen -= sizeof(*msg);
2137
2138         if (optlen < 0) {
2139                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2140                 return;
2141         }
2142
2143         msg = (struct rd_msg *)icmp6_hdr(skb);
2144
2145         if (ipv6_addr_is_multicast(&msg->dest)) {
2146                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2147                 return;
2148         }
2149
2150         on_link = 0;
2151         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2152                 on_link = 1;
2153         } else if (ipv6_addr_type(&msg->target) !=
2154                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2155                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2156                 return;
2157         }
2158
2159         in6_dev = __in6_dev_get(skb->dev);
2160         if (!in6_dev)
2161                 return;
2162         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2163                 return;
2164
2165         /* RFC2461 8.1:
2166          *      The IP source address of the Redirect MUST be the same as the current
2167          *      first-hop router for the specified ICMP Destination Address.
2168          */
2169
2170         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2171                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2172                 return;
2173         }
2174
2175         lladdr = NULL;
2176         if (ndopts.nd_opts_tgt_lladdr) {
2177                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2178                                              skb->dev);
2179                 if (!lladdr) {
2180                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2181                         return;
2182                 }
2183         }
2184
2185         rt = (struct rt6_info *) dst;
2186         if (rt->rt6i_flags & RTF_REJECT) {
2187                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2188                 return;
2189         }
2190
2191         /* Redirect received -> path was valid.
2192          * Look, redirects are sent only in response to data packets,
2193          * so that this nexthop apparently is reachable. --ANK
2194          */
2195         dst_confirm(&rt->dst);
2196
2197         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2198         if (!neigh)
2199                 return;
2200
2201         /*
2202          *      We have finally decided to accept it.
2203          */
2204
2205         neigh_update(neigh, lladdr, NUD_STALE,
2206                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2207                      NEIGH_UPDATE_F_OVERRIDE|
2208                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2209                                      NEIGH_UPDATE_F_ISROUTER))
2210                      );
2211
2212         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2213         if (!nrt)
2214                 goto out;
2215
2216         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2217         if (on_link)
2218                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2219
2220         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2221
2222         if (ip6_ins_rt(nrt))
2223                 goto out;
2224
2225         netevent.old = &rt->dst;
2226         netevent.new = &nrt->dst;
2227         netevent.daddr = &msg->dest;
2228         netevent.neigh = neigh;
2229         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2230
2231         if (rt->rt6i_flags & RTF_CACHE) {
2232                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2233                 ip6_del_rt(rt);
2234         }
2235
2236 out:
2237         neigh_release(neigh);
2238 }
2239
2240 /*
2241  *      Misc support functions
2242  */
2243
2244 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2245 {
2246         BUG_ON(from->dst.from);
2247
2248         rt->rt6i_flags &= ~RTF_EXPIRES;
2249         dst_hold(&from->dst);
2250         rt->dst.from = &from->dst;
2251         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2252 }
2253
2254 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2255 {
2256         rt->dst.input = ort->dst.input;
2257         rt->dst.output = ort->dst.output;
2258         rt->rt6i_dst = ort->rt6i_dst;
2259         rt->dst.error = ort->dst.error;
2260         rt->rt6i_idev = ort->rt6i_idev;
2261         if (rt->rt6i_idev)
2262                 in6_dev_hold(rt->rt6i_idev);
2263         rt->dst.lastuse = jiffies;
2264         rt->rt6i_gateway = ort->rt6i_gateway;
2265         rt->rt6i_flags = ort->rt6i_flags;
2266         rt6_set_from(rt, ort);
2267         rt->rt6i_metric = ort->rt6i_metric;
2268 #ifdef CONFIG_IPV6_SUBTREES
2269         rt->rt6i_src = ort->rt6i_src;
2270 #endif
2271         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2272         rt->rt6i_table = ort->rt6i_table;
2273         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2274 }
2275
2276 #ifdef CONFIG_IPV6_ROUTE_INFO
2277 static struct rt6_info *rt6_get_route_info(struct net *net,
2278                                            const struct in6_addr *prefix, int prefixlen,
2279                                            const struct in6_addr *gwaddr,
2280                                            struct net_device *dev)
2281 {
2282         u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
2283         int ifindex = dev->ifindex;
2284         struct fib6_node *fn;
2285         struct rt6_info *rt = NULL;
2286         struct fib6_table *table;
2287
2288         table = fib6_get_table(net, tb_id);
2289         if (!table)
2290                 return NULL;
2291
2292         read_lock_bh(&table->tb6_lock);
2293         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2294         if (!fn)
2295                 goto out;
2296
2297         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2298                 if (rt->dst.dev->ifindex != ifindex)
2299                         continue;
2300                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2301                         continue;
2302                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2303                         continue;
2304                 dst_hold(&rt->dst);
2305                 break;
2306         }
2307 out:
2308         read_unlock_bh(&table->tb6_lock);
2309         return rt;
2310 }
2311
2312 static struct rt6_info *rt6_add_route_info(struct net *net,
2313                                            const struct in6_addr *prefix, int prefixlen,
2314                                            const struct in6_addr *gwaddr,
2315                                            struct net_device *dev,
2316                                            unsigned int pref)
2317 {
2318         struct fib6_config cfg = {
2319                 .fc_metric      = IP6_RT_PRIO_USER,
2320                 .fc_ifindex     = dev->ifindex,
2321                 .fc_dst_len     = prefixlen,
2322                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2323                                   RTF_UP | RTF_PREF(pref),
2324                 .fc_nlinfo.portid = 0,
2325                 .fc_nlinfo.nlh = NULL,
2326                 .fc_nlinfo.nl_net = net,
2327         };
2328
2329         cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO,
2330         cfg.fc_dst = *prefix;
2331         cfg.fc_gateway = *gwaddr;
2332
2333         /* We should treat it as a default route if prefix length is 0. */
2334         if (!prefixlen)
2335                 cfg.fc_flags |= RTF_DEFAULT;
2336
2337         ip6_route_add(&cfg);
2338
2339         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
2340 }
2341 #endif
2342
2343 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2344 {
2345         u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT;
2346         struct rt6_info *rt;
2347         struct fib6_table *table;
2348
2349         table = fib6_get_table(dev_net(dev), tb_id);
2350         if (!table)
2351                 return NULL;
2352
2353         read_lock_bh(&table->tb6_lock);
2354         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2355                 if (dev == rt->dst.dev &&
2356                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2357                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2358                         break;
2359         }
2360         if (rt)
2361                 dst_hold(&rt->dst);
2362         read_unlock_bh(&table->tb6_lock);
2363         return rt;
2364 }
2365
2366 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2367                                      struct net_device *dev,
2368                                      unsigned int pref)
2369 {
2370         struct fib6_config cfg = {
2371                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2372                 .fc_metric      = IP6_RT_PRIO_USER,
2373                 .fc_ifindex     = dev->ifindex,
2374                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2375                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2376                 .fc_nlinfo.portid = 0,
2377                 .fc_nlinfo.nlh = NULL,
2378                 .fc_nlinfo.nl_net = dev_net(dev),
2379         };
2380
2381         cfg.fc_gateway = *gwaddr;
2382
2383         if (!ip6_route_add(&cfg)) {
2384                 struct fib6_table *table;
2385
2386                 table = fib6_get_table(dev_net(dev), cfg.fc_table);
2387                 if (table)
2388                         table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
2389         }
2390
2391         return rt6_get_dflt_router(gwaddr, dev);
2392 }
2393
2394 static void __rt6_purge_dflt_routers(struct fib6_table *table)
2395 {
2396         struct rt6_info *rt;
2397
2398 restart:
2399         read_lock_bh(&table->tb6_lock);
2400         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2401                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2402                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2403                         dst_hold(&rt->dst);
2404                         read_unlock_bh(&table->tb6_lock);
2405                         ip6_del_rt(rt);
2406                         goto restart;
2407                 }
2408         }
2409         read_unlock_bh(&table->tb6_lock);
2410
2411         table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
2412 }
2413
2414 void rt6_purge_dflt_routers(struct net *net)
2415 {
2416         struct fib6_table *table;
2417         struct hlist_head *head;
2418         unsigned int h;
2419
2420         rcu_read_lock();
2421
2422         for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
2423                 head = &net->ipv6.fib_table_hash[h];
2424                 hlist_for_each_entry_rcu(table, head, tb6_hlist) {
2425                         if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
2426                                 __rt6_purge_dflt_routers(table);
2427                 }
2428         }
2429
2430         rcu_read_unlock();
2431 }
2432
2433 static void rtmsg_to_fib6_config(struct net *net,
2434                                  struct in6_rtmsg *rtmsg,
2435                                  struct fib6_config *cfg)
2436 {
2437         memset(cfg, 0, sizeof(*cfg));
2438
2439         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2440                          : RT6_TABLE_MAIN;
2441         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2442         cfg->fc_metric = rtmsg->rtmsg_metric;
2443         cfg->fc_expires = rtmsg->rtmsg_info;
2444         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2445         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2446         cfg->fc_flags = rtmsg->rtmsg_flags;
2447
2448         cfg->fc_nlinfo.nl_net = net;
2449
2450         cfg->fc_dst = rtmsg->rtmsg_dst;
2451         cfg->fc_src = rtmsg->rtmsg_src;
2452         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2453 }
2454
2455 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2456 {
2457         struct fib6_config cfg;
2458         struct in6_rtmsg rtmsg;
2459         int err;
2460
2461         switch (cmd) {
2462         case SIOCADDRT:         /* Add a route */
2463         case SIOCDELRT:         /* Delete a route */
2464                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2465                         return -EPERM;
2466                 err = copy_from_user(&rtmsg, arg,
2467                                      sizeof(struct in6_rtmsg));
2468                 if (err)
2469                         return -EFAULT;
2470
2471                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2472
2473                 rtnl_lock();
2474                 switch (cmd) {
2475                 case SIOCADDRT:
2476                         err = ip6_route_add(&cfg);
2477                         break;
2478                 case SIOCDELRT:
2479                         err = ip6_route_del(&cfg);
2480                         break;
2481                 default:
2482                         err = -EINVAL;
2483                 }
2484                 rtnl_unlock();
2485
2486                 return err;
2487         }
2488
2489         return -EINVAL;
2490 }
2491
2492 /*
2493  *      Drop the packet on the floor
2494  */
2495
2496 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2497 {
2498         int type;
2499         struct dst_entry *dst = skb_dst(skb);
2500         switch (ipstats_mib_noroutes) {
2501         case IPSTATS_MIB_INNOROUTES:
2502                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2503                 if (type == IPV6_ADDR_ANY) {
2504                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2505                                       IPSTATS_MIB_INADDRERRORS);
2506                         break;
2507                 }
2508                 /* FALLTHROUGH */
2509         case IPSTATS_MIB_OUTNOROUTES:
2510                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2511                               ipstats_mib_noroutes);
2512                 break;
2513         }
2514         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2515         kfree_skb(skb);
2516         return 0;
2517 }
2518
2519 static int ip6_pkt_discard(struct sk_buff *skb)
2520 {
2521         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2522 }
2523
2524 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2525 {
2526         skb->dev = skb_dst(skb)->dev;
2527         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2528 }
2529
2530 static int ip6_pkt_prohibit(struct sk_buff *skb)
2531 {
2532         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2533 }
2534
2535 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2536 {
2537         skb->dev = skb_dst(skb)->dev;
2538         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2539 }
2540
2541 /*
2542  *      Allocate a dst for local (unicast / anycast) address.
2543  */
2544
2545 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2546                                     const struct in6_addr *addr,
2547                                     bool anycast)
2548 {
2549         u32 tb_id;
2550         struct net *net = dev_net(idev->dev);
2551         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2552                                             DST_NOCOUNT);
2553         if (!rt)
2554                 return ERR_PTR(-ENOMEM);
2555
2556         in6_dev_hold(idev);
2557
2558         rt->dst.flags |= DST_HOST;
2559         rt->dst.input = ip6_input;
2560         rt->dst.output = ip6_output;
2561         rt->rt6i_idev = idev;
2562
2563         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2564         if (anycast)
2565                 rt->rt6i_flags |= RTF_ANYCAST;
2566         else
2567                 rt->rt6i_flags |= RTF_LOCAL;
2568
2569         rt->rt6i_gateway  = *addr;
2570         rt->rt6i_dst.addr = *addr;
2571         rt->rt6i_dst.plen = 128;
2572         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2573         rt->rt6i_table = fib6_get_table(net, tb_id);
2574         rt->dst.flags |= DST_NOCACHE;
2575
2576         atomic_set(&rt->dst.__refcnt, 1);
2577
2578         return rt;
2579 }
2580
2581 int ip6_route_get_saddr(struct net *net,
2582                         struct rt6_info *rt,
2583                         const struct in6_addr *daddr,
2584                         unsigned int prefs,
2585                         struct in6_addr *saddr)
2586 {
2587         struct inet6_dev *idev =
2588                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2589         int err = 0;
2590         if (rt && rt->rt6i_prefsrc.plen)
2591                 *saddr = rt->rt6i_prefsrc.addr;
2592         else
2593                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2594                                          daddr, prefs, saddr);
2595         return err;
2596 }
2597
2598 /* remove deleted ip from prefsrc entries */
2599 struct arg_dev_net_ip {
2600         struct net_device *dev;
2601         struct net *net;
2602         struct in6_addr *addr;
2603 };
2604
2605 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2606 {
2607         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2608         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2609         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2610
2611         if (((void *)rt->dst.dev == dev || !dev) &&
2612             rt != net->ipv6.ip6_null_entry &&
2613             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2614                 /* remove prefsrc entry */
2615                 rt->rt6i_prefsrc.plen = 0;
2616         }
2617         return 0;
2618 }
2619
2620 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2621 {
2622         struct net *net = dev_net(ifp->idev->dev);
2623         struct arg_dev_net_ip adni = {
2624                 .dev = ifp->idev->dev,
2625                 .net = net,
2626                 .addr = &ifp->addr,
2627         };
2628         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2629 }
2630
2631 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2632 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2633
2634 /* Remove routers and update dst entries when gateway turn into host. */
2635 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2636 {
2637         struct in6_addr *gateway = (struct in6_addr *)arg;
2638
2639         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2640              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2641              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2642                 return -1;
2643         }
2644         return 0;
2645 }
2646
2647 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2648 {
2649         fib6_clean_all(net, fib6_clean_tohost, gateway);
2650 }
2651
2652 struct arg_dev_net {
2653         struct net_device *dev;
2654         struct net *net;
2655 };
2656
2657 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2658 {
2659         const struct arg_dev_net *adn = arg;
2660         const struct net_device *dev = adn->dev;
2661
2662         if ((rt->dst.dev == dev || !dev) &&
2663             rt != adn->net->ipv6.ip6_null_entry)
2664                 return -1;
2665
2666         return 0;
2667 }
2668
2669 void rt6_ifdown(struct net *net, struct net_device *dev)
2670 {
2671         struct arg_dev_net adn = {
2672                 .dev = dev,
2673                 .net = net,
2674         };
2675
2676         fib6_clean_all(net, fib6_ifdown, &adn);
2677         icmp6_clean_all(fib6_ifdown, &adn);
2678         if (dev)
2679                 rt6_uncached_list_flush_dev(net, dev);
2680 }
2681
2682 struct rt6_mtu_change_arg {
2683         struct net_device *dev;
2684         unsigned int mtu;
2685 };
2686
2687 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2688 {
2689         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2690         struct inet6_dev *idev;
2691
2692         /* In IPv6 pmtu discovery is not optional,
2693            so that RTAX_MTU lock cannot disable it.
2694            We still use this lock to block changes
2695            caused by addrconf/ndisc.
2696         */
2697
2698         idev = __in6_dev_get(arg->dev);
2699         if (!idev)
2700                 return 0;
2701
2702         /* For administrative MTU increase, there is no way to discover
2703            IPv6 PMTU increase, so PMTU increase should be updated here.
2704            Since RFC 1981 doesn't include administrative MTU increase
2705            update PMTU increase is a MUST. (i.e. jumbo frame)
2706          */
2707         /*
2708            If new MTU is less than route PMTU, this new MTU will be the
2709            lowest MTU in the path, update the route PMTU to reflect PMTU
2710            decreases; if new MTU is greater than route PMTU, and the
2711            old MTU is the lowest MTU in the path, update the route PMTU
2712            to reflect the increase. In this case if the other nodes' MTU
2713            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2714            PMTU discouvery.
2715          */
2716         if (rt->dst.dev == arg->dev &&
2717             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2718                 if (rt->rt6i_flags & RTF_CACHE) {
2719                         /* For RTF_CACHE with rt6i_pmtu == 0
2720                          * (i.e. a redirected route),
2721                          * the metrics of its rt->dst.from has already
2722                          * been updated.
2723                          */
2724                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2725                                 rt->rt6i_pmtu = arg->mtu;
2726                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2727                            (dst_mtu(&rt->dst) < arg->mtu &&
2728                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2729                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2730                 }
2731         }
2732         return 0;
2733 }
2734
2735 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2736 {
2737         struct rt6_mtu_change_arg arg = {
2738                 .dev = dev,
2739                 .mtu = mtu,
2740         };
2741
2742         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2743 }
2744
2745 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2746         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2747         [RTA_PREFSRC]           = { .len = sizeof(struct in6_addr) },
2748         [RTA_OIF]               = { .type = NLA_U32 },
2749         [RTA_IIF]               = { .type = NLA_U32 },
2750         [RTA_PRIORITY]          = { .type = NLA_U32 },
2751         [RTA_METRICS]           = { .type = NLA_NESTED },
2752         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2753         [RTA_PREF]              = { .type = NLA_U8 },
2754         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2755         [RTA_ENCAP]             = { .type = NLA_NESTED },
2756         [RTA_TABLE]             = { .type = NLA_U32 },
2757 };
2758
2759 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2760                               struct fib6_config *cfg)
2761 {
2762         struct rtmsg *rtm;
2763         struct nlattr *tb[RTA_MAX+1];
2764         unsigned int pref;
2765         int err;
2766
2767         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2768         if (err < 0)
2769                 goto errout;
2770
2771         err = -EINVAL;
2772         rtm = nlmsg_data(nlh);
2773         memset(cfg, 0, sizeof(*cfg));
2774
2775         cfg->fc_table = rtm->rtm_table;
2776         cfg->fc_dst_len = rtm->rtm_dst_len;
2777         cfg->fc_src_len = rtm->rtm_src_len;
2778         cfg->fc_flags = RTF_UP;
2779         cfg->fc_protocol = rtm->rtm_protocol;
2780         cfg->fc_type = rtm->rtm_type;
2781
2782         if (rtm->rtm_type == RTN_UNREACHABLE ||
2783             rtm->rtm_type == RTN_BLACKHOLE ||
2784             rtm->rtm_type == RTN_PROHIBIT ||
2785             rtm->rtm_type == RTN_THROW)
2786                 cfg->fc_flags |= RTF_REJECT;
2787
2788         if (rtm->rtm_type == RTN_LOCAL)
2789                 cfg->fc_flags |= RTF_LOCAL;
2790
2791         if (rtm->rtm_flags & RTM_F_CLONED)
2792                 cfg->fc_flags |= RTF_CACHE;
2793
2794         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2795         cfg->fc_nlinfo.nlh = nlh;
2796         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2797
2798         if (tb[RTA_GATEWAY]) {
2799                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2800                 cfg->fc_flags |= RTF_GATEWAY;
2801         }
2802
2803         if (tb[RTA_DST]) {
2804                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2805
2806                 if (nla_len(tb[RTA_DST]) < plen)
2807                         goto errout;
2808
2809                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2810         }
2811
2812         if (tb[RTA_SRC]) {
2813                 int plen = (rtm->rtm_src_len + 7) >> 3;
2814
2815                 if (nla_len(tb[RTA_SRC]) < plen)
2816                         goto errout;
2817
2818                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2819         }
2820
2821         if (tb[RTA_PREFSRC])
2822                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2823
2824         if (tb[RTA_OIF])
2825                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2826
2827         if (tb[RTA_PRIORITY])
2828                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2829
2830         if (tb[RTA_METRICS]) {
2831                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2832                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2833         }
2834
2835         if (tb[RTA_TABLE])
2836                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2837
2838         if (tb[RTA_MULTIPATH]) {
2839                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2840                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2841         }
2842
2843         if (tb[RTA_PREF]) {
2844                 pref = nla_get_u8(tb[RTA_PREF]);
2845                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2846                     pref != ICMPV6_ROUTER_PREF_HIGH)
2847                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2848                 cfg->fc_flags |= RTF_PREF(pref);
2849         }
2850
2851         if (tb[RTA_ENCAP])
2852                 cfg->fc_encap = tb[RTA_ENCAP];
2853
2854         if (tb[RTA_ENCAP_TYPE])
2855                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2856
2857         err = 0;
2858 errout:
2859         return err;
2860 }
2861
2862 struct rt6_nh {
2863         struct rt6_info *rt6_info;
2864         struct fib6_config r_cfg;
2865         struct mx6_config mxc;
2866         struct list_head next;
2867 };
2868
2869 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2870 {
2871         struct rt6_nh *nh;
2872
2873         list_for_each_entry(nh, rt6_nh_list, next) {
2874                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2875                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2876                         nh->r_cfg.fc_ifindex);
2877         }
2878 }
2879
2880 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2881                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2882 {
2883         struct rt6_nh *nh;
2884         int err = -EEXIST;
2885
2886         list_for_each_entry(nh, rt6_nh_list, next) {
2887                 /* check if rt6_info already exists */
2888                 if (rt6_duplicate_nexthop(nh->rt6_info, rt))
2889                         return err;
2890         }
2891
2892         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2893         if (!nh)
2894                 return -ENOMEM;
2895         nh->rt6_info = rt;
2896         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2897         if (err) {
2898                 kfree(nh);
2899                 return err;
2900         }
2901         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2902         list_add_tail(&nh->next, rt6_nh_list);
2903
2904         return 0;
2905 }
2906
2907 static int ip6_route_multipath_add(struct fib6_config *cfg)
2908 {
2909         struct fib6_config r_cfg;
2910         struct rtnexthop *rtnh;
2911         struct rt6_info *rt;
2912         struct rt6_nh *err_nh;
2913         struct rt6_nh *nh, *nh_safe;
2914         int remaining;
2915         int attrlen;
2916         int err = 1;
2917         int nhn = 0;
2918         int replace = (cfg->fc_nlinfo.nlh &&
2919                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2920         LIST_HEAD(rt6_nh_list);
2921
2922         remaining = cfg->fc_mp_len;
2923         rtnh = (struct rtnexthop *)cfg->fc_mp;
2924
2925         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2926          * rt6_info structs per nexthop
2927          */
2928         while (rtnh_ok(rtnh, remaining)) {
2929                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2930                 if (rtnh->rtnh_ifindex)
2931                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2932
2933                 attrlen = rtnh_attrlen(rtnh);
2934                 if (attrlen > 0) {
2935                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2936
2937                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2938                         if (nla) {
2939                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2940                                 r_cfg.fc_flags |= RTF_GATEWAY;
2941                         }
2942                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2943                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2944                         if (nla)
2945                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2946                 }
2947
2948                 rt = ip6_route_info_create(&r_cfg);
2949                 if (IS_ERR(rt)) {
2950                         err = PTR_ERR(rt);
2951                         rt = NULL;
2952                         goto cleanup;
2953                 }
2954
2955                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2956                 if (err) {
2957                         dst_free(&rt->dst);
2958                         goto cleanup;
2959                 }
2960
2961                 rtnh = rtnh_next(rtnh, &remaining);
2962         }
2963
2964         err_nh = NULL;
2965         list_for_each_entry(nh, &rt6_nh_list, next) {
2966                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2967                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2968                 nh->rt6_info = NULL;
2969                 if (err) {
2970                         if (replace && nhn)
2971                                 ip6_print_replace_route_err(&rt6_nh_list);
2972                         err_nh = nh;
2973                         goto add_errout;
2974                 }
2975
2976                 /* Because each route is added like a single route we remove
2977                  * these flags after the first nexthop: if there is a collision,
2978                  * we have already failed to add the first nexthop:
2979                  * fib6_add_rt2node() has rejected it; when replacing, old
2980                  * nexthops have been replaced by first new, the rest should
2981                  * be added to it.
2982                  */
2983                 if (cfg->fc_nlinfo.nlh) {
2984                         cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2985                                                              NLM_F_REPLACE);
2986                         cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
2987                 }
2988                 nhn++;
2989         }
2990
2991         goto cleanup;
2992
2993 add_errout:
2994         /* Delete routes that were already added */
2995         list_for_each_entry(nh, &rt6_nh_list, next) {
2996                 if (err_nh == nh)
2997                         break;
2998                 ip6_route_del(&nh->r_cfg);
2999         }
3000
3001 cleanup:
3002         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
3003                 if (nh->rt6_info)
3004                         dst_free(&nh->rt6_info->dst);
3005                 kfree(nh->mxc.mx);
3006                 list_del(&nh->next);
3007                 kfree(nh);
3008         }
3009
3010         return err;
3011 }
3012
3013 static int ip6_route_multipath_del(struct fib6_config *cfg)
3014 {
3015         struct fib6_config r_cfg;
3016         struct rtnexthop *rtnh;
3017         int remaining;
3018         int attrlen;
3019         int err = 1, last_err = 0;
3020
3021         remaining = cfg->fc_mp_len;
3022         rtnh = (struct rtnexthop *)cfg->fc_mp;
3023
3024         /* Parse a Multipath Entry */
3025         while (rtnh_ok(rtnh, remaining)) {
3026                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3027                 if (rtnh->rtnh_ifindex)
3028                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3029
3030                 attrlen = rtnh_attrlen(rtnh);
3031                 if (attrlen > 0) {
3032                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3033
3034                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3035                         if (nla) {
3036                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3037                                 r_cfg.fc_flags |= RTF_GATEWAY;
3038                         }
3039                 }
3040                 err = ip6_route_del(&r_cfg);
3041                 if (err)
3042                         last_err = err;
3043
3044                 rtnh = rtnh_next(rtnh, &remaining);
3045         }
3046
3047         return last_err;
3048 }
3049
3050 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3051 {
3052         struct fib6_config cfg;
3053         int err;
3054
3055         err = rtm_to_fib6_config(skb, nlh, &cfg);
3056         if (err < 0)
3057                 return err;
3058
3059         if (cfg.fc_mp)
3060                 return ip6_route_multipath_del(&cfg);
3061         else
3062                 return ip6_route_del(&cfg);
3063 }
3064
3065 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3066 {
3067         struct fib6_config cfg;
3068         int err;
3069
3070         err = rtm_to_fib6_config(skb, nlh, &cfg);
3071         if (err < 0)
3072                 return err;
3073
3074         if (cfg.fc_mp)
3075                 return ip6_route_multipath_add(&cfg);
3076         else
3077                 return ip6_route_add(&cfg);
3078 }
3079
3080 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3081 {
3082         return NLMSG_ALIGN(sizeof(struct rtmsg))
3083                + nla_total_size(16) /* RTA_SRC */
3084                + nla_total_size(16) /* RTA_DST */
3085                + nla_total_size(16) /* RTA_GATEWAY */
3086                + nla_total_size(16) /* RTA_PREFSRC */
3087                + nla_total_size(4) /* RTA_TABLE */
3088                + nla_total_size(4) /* RTA_IIF */
3089                + nla_total_size(4) /* RTA_OIF */
3090                + nla_total_size(4) /* RTA_PRIORITY */
3091                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3092                + nla_total_size(sizeof(struct rta_cacheinfo))
3093                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3094                + nla_total_size(1) /* RTA_PREF */
3095                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3096 }
3097
3098 static int rt6_fill_node(struct net *net,
3099                          struct sk_buff *skb, struct rt6_info *rt,
3100                          struct in6_addr *dst, struct in6_addr *src,
3101                          int iif, int type, u32 portid, u32 seq,
3102                          int prefix, int nowait, unsigned int flags)
3103 {
3104         u32 metrics[RTAX_MAX];
3105         struct rtmsg *rtm;
3106         struct nlmsghdr *nlh;
3107         long expires;
3108         u32 table;
3109
3110         if (prefix) {   /* user wants prefix routes only */
3111                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3112                         /* success since this is not a prefix route */
3113                         return 1;
3114                 }
3115         }
3116
3117         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3118         if (!nlh)
3119                 return -EMSGSIZE;
3120
3121         rtm = nlmsg_data(nlh);
3122         rtm->rtm_family = AF_INET6;
3123         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3124         rtm->rtm_src_len = rt->rt6i_src.plen;
3125         rtm->rtm_tos = 0;
3126         if (rt->rt6i_table)
3127                 table = rt->rt6i_table->tb6_id;
3128         else
3129                 table = RT6_TABLE_UNSPEC;
3130         rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
3131         if (nla_put_u32(skb, RTA_TABLE, table))
3132                 goto nla_put_failure;
3133         if (rt->rt6i_flags & RTF_REJECT) {
3134                 switch (rt->dst.error) {
3135                 case -EINVAL:
3136                         rtm->rtm_type = RTN_BLACKHOLE;
3137                         break;
3138                 case -EACCES:
3139                         rtm->rtm_type = RTN_PROHIBIT;
3140                         break;
3141                 case -EAGAIN:
3142                         rtm->rtm_type = RTN_THROW;
3143                         break;
3144                 default:
3145                         rtm->rtm_type = RTN_UNREACHABLE;
3146                         break;
3147                 }
3148         }
3149         else if (rt->rt6i_flags & RTF_LOCAL)
3150                 rtm->rtm_type = RTN_LOCAL;
3151         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3152                 rtm->rtm_type = RTN_LOCAL;
3153         else
3154                 rtm->rtm_type = RTN_UNICAST;
3155         rtm->rtm_flags = 0;
3156         if (!netif_carrier_ok(rt->dst.dev)) {
3157                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3158                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3159                         rtm->rtm_flags |= RTNH_F_DEAD;
3160         }
3161         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3162         rtm->rtm_protocol = rt->rt6i_protocol;
3163         if (rt->rt6i_flags & RTF_DYNAMIC)
3164                 rtm->rtm_protocol = RTPROT_REDIRECT;
3165         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3166                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3167                         rtm->rtm_protocol = RTPROT_RA;
3168                 else
3169                         rtm->rtm_protocol = RTPROT_KERNEL;
3170         }
3171
3172         if (rt->rt6i_flags & RTF_CACHE)
3173                 rtm->rtm_flags |= RTM_F_CLONED;
3174
3175         if (dst) {
3176                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3177                         goto nla_put_failure;
3178                 rtm->rtm_dst_len = 128;
3179         } else if (rtm->rtm_dst_len)
3180                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3181                         goto nla_put_failure;
3182 #ifdef CONFIG_IPV6_SUBTREES
3183         if (src) {
3184                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3185                         goto nla_put_failure;
3186                 rtm->rtm_src_len = 128;
3187         } else if (rtm->rtm_src_len &&
3188                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3189                 goto nla_put_failure;
3190 #endif
3191         if (iif) {
3192 #ifdef CONFIG_IPV6_MROUTE
3193                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3194                         int err = ip6mr_get_route(net, skb, rtm, nowait,
3195                                                   portid);
3196
3197                         if (err <= 0) {
3198                                 if (!nowait) {
3199                                         if (err == 0)
3200                                                 return 0;
3201                                         goto nla_put_failure;
3202                                 } else {
3203                                         if (err == -EMSGSIZE)
3204                                                 goto nla_put_failure;
3205                                 }
3206                         }
3207                 } else
3208 #endif
3209                         if (nla_put_u32(skb, RTA_IIF, iif))
3210                                 goto nla_put_failure;
3211         } else if (dst) {
3212                 struct in6_addr saddr_buf;
3213                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3214                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3215                         goto nla_put_failure;
3216         }
3217
3218         if (rt->rt6i_prefsrc.plen) {
3219                 struct in6_addr saddr_buf;
3220                 saddr_buf = rt->rt6i_prefsrc.addr;
3221                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3222                         goto nla_put_failure;
3223         }
3224
3225         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3226         if (rt->rt6i_pmtu)
3227                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3228         if (rtnetlink_put_metrics(skb, metrics) < 0)
3229                 goto nla_put_failure;
3230
3231         if (rt->rt6i_flags & RTF_GATEWAY) {
3232                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3233                         goto nla_put_failure;
3234         }
3235
3236         if (rt->dst.dev &&
3237             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3238                 goto nla_put_failure;
3239         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3240                 goto nla_put_failure;
3241
3242         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3243
3244         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3245                 goto nla_put_failure;
3246
3247         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3248                 goto nla_put_failure;
3249
3250         if (lwtunnel_fill_encap(skb, rt->dst.lwtstate) < 0)
3251                 goto nla_put_failure;
3252
3253         nlmsg_end(skb, nlh);
3254         return 0;
3255
3256 nla_put_failure:
3257         nlmsg_cancel(skb, nlh);
3258         return -EMSGSIZE;
3259 }
3260
3261 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3262 {
3263         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3264         int prefix;
3265
3266         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3267                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3268                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3269         } else
3270                 prefix = 0;
3271
3272         return rt6_fill_node(arg->net,
3273                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3274                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3275                      prefix, 0, NLM_F_MULTI);
3276 }
3277
3278 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3279 {
3280         struct net *net = sock_net(in_skb->sk);
3281         struct nlattr *tb[RTA_MAX+1];
3282         struct rt6_info *rt;
3283         struct sk_buff *skb;
3284         struct rtmsg *rtm;
3285         struct flowi6 fl6;
3286         int err, iif = 0, oif = 0;
3287
3288         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3289         if (err < 0)
3290                 goto errout;
3291
3292         err = -EINVAL;
3293         memset(&fl6, 0, sizeof(fl6));
3294
3295         if (tb[RTA_SRC]) {
3296                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3297                         goto errout;
3298
3299                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3300         }
3301
3302         if (tb[RTA_DST]) {
3303                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3304                         goto errout;
3305
3306                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3307         }
3308
3309         if (tb[RTA_IIF])
3310                 iif = nla_get_u32(tb[RTA_IIF]);
3311
3312         if (tb[RTA_OIF])
3313                 oif = nla_get_u32(tb[RTA_OIF]);
3314
3315         if (tb[RTA_MARK])
3316                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3317
3318         if (iif) {
3319                 struct net_device *dev;
3320                 int flags = 0;
3321
3322                 dev = __dev_get_by_index(net, iif);
3323                 if (!dev) {
3324                         err = -ENODEV;
3325                         goto errout;
3326                 }
3327
3328                 fl6.flowi6_iif = iif;
3329
3330                 if (!ipv6_addr_any(&fl6.saddr))
3331                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3332
3333                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3334                                                                flags);
3335         } else {
3336                 fl6.flowi6_oif = oif;
3337
3338                 if (netif_index_is_l3_master(net, oif)) {
3339                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3340                                            FLOWI_FLAG_SKIP_NH_OIF;
3341                 }
3342
3343                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3344         }
3345
3346         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3347         if (!skb) {
3348                 ip6_rt_put(rt);
3349                 err = -ENOBUFS;
3350                 goto errout;
3351         }
3352
3353         /* Reserve room for dummy headers, this skb can pass
3354            through good chunk of routing engine.
3355          */
3356         skb_reset_mac_header(skb);
3357         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3358
3359         skb_dst_set(skb, &rt->dst);
3360
3361         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3362                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3363                             nlh->nlmsg_seq, 0, 0, 0);
3364         if (err < 0) {
3365                 kfree_skb(skb);
3366                 goto errout;
3367         }
3368
3369         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3370 errout:
3371         return err;
3372 }
3373
3374 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3375                      unsigned int nlm_flags)
3376 {
3377         struct sk_buff *skb;
3378         struct net *net = info->nl_net;
3379         u32 seq;
3380         int err;
3381
3382         err = -ENOBUFS;
3383         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3384
3385         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3386         if (!skb)
3387                 goto errout;
3388
3389         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3390                                 event, info->portid, seq, 0, 0, nlm_flags);
3391         if (err < 0) {
3392                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3393                 WARN_ON(err == -EMSGSIZE);
3394                 kfree_skb(skb);
3395                 goto errout;
3396         }
3397         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3398                     info->nlh, gfp_any());
3399         return;
3400 errout:
3401         if (err < 0)
3402                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3403 }
3404
3405 static int ip6_route_dev_notify(struct notifier_block *this,
3406                                 unsigned long event, void *ptr)
3407 {
3408         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3409         struct net *net = dev_net(dev);
3410
3411         if (!(dev->flags & IFF_LOOPBACK))
3412                 return NOTIFY_OK;
3413
3414         if (event == NETDEV_REGISTER) {
3415                 net->ipv6.ip6_null_entry->dst.dev = dev;
3416                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3417 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3418                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3419                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3420                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3421                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3422 #endif
3423          } else if (event == NETDEV_UNREGISTER &&
3424                     dev->reg_state != NETREG_UNREGISTERED) {
3425                 /* NETDEV_UNREGISTER could be fired for multiple times by
3426                  * netdev_wait_allrefs(). Make sure we only call this once.
3427                  */
3428                 in6_dev_put(net->ipv6.ip6_null_entry->rt6i_idev);
3429 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3430                 in6_dev_put(net->ipv6.ip6_prohibit_entry->rt6i_idev);
3431                 in6_dev_put(net->ipv6.ip6_blk_hole_entry->rt6i_idev);
3432 #endif
3433         }
3434
3435         return NOTIFY_OK;
3436 }
3437
3438 /*
3439  *      /proc
3440  */
3441
3442 #ifdef CONFIG_PROC_FS
3443
3444 static const struct file_operations ipv6_route_proc_fops = {
3445         .owner          = THIS_MODULE,
3446         .open           = ipv6_route_open,
3447         .read           = seq_read,
3448         .llseek         = seq_lseek,
3449         .release        = seq_release_net,
3450 };
3451
3452 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3453 {
3454         struct net *net = (struct net *)seq->private;
3455         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3456                    net->ipv6.rt6_stats->fib_nodes,
3457                    net->ipv6.rt6_stats->fib_route_nodes,
3458                    net->ipv6.rt6_stats->fib_rt_alloc,
3459                    net->ipv6.rt6_stats->fib_rt_entries,
3460                    net->ipv6.rt6_stats->fib_rt_cache,
3461                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3462                    net->ipv6.rt6_stats->fib_discarded_routes);
3463
3464         return 0;
3465 }
3466
3467 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3468 {
3469         return single_open_net(inode, file, rt6_stats_seq_show);
3470 }
3471
3472 static const struct file_operations rt6_stats_seq_fops = {
3473         .owner   = THIS_MODULE,
3474         .open    = rt6_stats_seq_open,
3475         .read    = seq_read,
3476         .llseek  = seq_lseek,
3477         .release = single_release_net,
3478 };
3479 #endif  /* CONFIG_PROC_FS */
3480
3481 #ifdef CONFIG_SYSCTL
3482
3483 static
3484 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3485                               void __user *buffer, size_t *lenp, loff_t *ppos)
3486 {
3487         struct net *net;
3488         int delay;
3489         if (!write)
3490                 return -EINVAL;
3491
3492         net = (struct net *)ctl->extra1;
3493         delay = net->ipv6.sysctl.flush_delay;
3494         proc_dointvec(ctl, write, buffer, lenp, ppos);
3495         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3496         return 0;
3497 }
3498
3499 struct ctl_table ipv6_route_table_template[] = {
3500         {
3501                 .procname       =       "flush",
3502                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3503                 .maxlen         =       sizeof(int),
3504                 .mode           =       0200,
3505                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3506         },
3507         {
3508                 .procname       =       "gc_thresh",
3509                 .data           =       &ip6_dst_ops_template.gc_thresh,
3510                 .maxlen         =       sizeof(int),
3511                 .mode           =       0644,
3512                 .proc_handler   =       proc_dointvec,
3513         },
3514         {
3515                 .procname       =       "max_size",
3516                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3517                 .maxlen         =       sizeof(int),
3518                 .mode           =       0644,
3519                 .proc_handler   =       proc_dointvec,
3520         },
3521         {
3522                 .procname       =       "gc_min_interval",
3523                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3524                 .maxlen         =       sizeof(int),
3525                 .mode           =       0644,
3526                 .proc_handler   =       proc_dointvec_jiffies,
3527         },
3528         {
3529                 .procname       =       "gc_timeout",
3530                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3531                 .maxlen         =       sizeof(int),
3532                 .mode           =       0644,
3533                 .proc_handler   =       proc_dointvec_jiffies,
3534         },
3535         {
3536                 .procname       =       "gc_interval",
3537                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3538                 .maxlen         =       sizeof(int),
3539                 .mode           =       0644,
3540                 .proc_handler   =       proc_dointvec_jiffies,
3541         },
3542         {
3543                 .procname       =       "gc_elasticity",
3544                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3545                 .maxlen         =       sizeof(int),
3546                 .mode           =       0644,
3547                 .proc_handler   =       proc_dointvec,
3548         },
3549         {
3550                 .procname       =       "mtu_expires",
3551                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3552                 .maxlen         =       sizeof(int),
3553                 .mode           =       0644,
3554                 .proc_handler   =       proc_dointvec_jiffies,
3555         },
3556         {
3557                 .procname       =       "min_adv_mss",
3558                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3559                 .maxlen         =       sizeof(int),
3560                 .mode           =       0644,
3561                 .proc_handler   =       proc_dointvec,
3562         },
3563         {
3564                 .procname       =       "gc_min_interval_ms",
3565                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3566                 .maxlen         =       sizeof(int),
3567                 .mode           =       0644,
3568                 .proc_handler   =       proc_dointvec_ms_jiffies,
3569         },
3570         { }
3571 };
3572
3573 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3574 {
3575         struct ctl_table *table;
3576
3577         table = kmemdup(ipv6_route_table_template,
3578                         sizeof(ipv6_route_table_template),
3579                         GFP_KERNEL);
3580
3581         if (table) {
3582                 table[0].data = &net->ipv6.sysctl.flush_delay;
3583                 table[0].extra1 = net;
3584                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3585                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3586                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3587                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3588                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3589                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3590                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3591                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3592                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3593
3594                 /* Don't export sysctls to unprivileged users */
3595                 if (net->user_ns != &init_user_ns)
3596                         table[0].procname = NULL;
3597         }
3598
3599         return table;
3600 }
3601 #endif
3602
3603 static int __net_init ip6_route_net_init(struct net *net)
3604 {
3605         int ret = -ENOMEM;
3606
3607         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3608                sizeof(net->ipv6.ip6_dst_ops));
3609
3610         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3611                 goto out_ip6_dst_ops;
3612
3613         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3614                                            sizeof(*net->ipv6.ip6_null_entry),
3615                                            GFP_KERNEL);
3616         if (!net->ipv6.ip6_null_entry)
3617                 goto out_ip6_dst_entries;
3618         net->ipv6.ip6_null_entry->dst.path =
3619                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3620         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3621         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3622                          ip6_template_metrics, true);
3623
3624 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3625         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3626                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3627                                                GFP_KERNEL);
3628         if (!net->ipv6.ip6_prohibit_entry)
3629                 goto out_ip6_null_entry;
3630         net->ipv6.ip6_prohibit_entry->dst.path =
3631                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3632         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3633         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3634                          ip6_template_metrics, true);
3635
3636         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3637                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3638                                                GFP_KERNEL);
3639         if (!net->ipv6.ip6_blk_hole_entry)
3640                 goto out_ip6_prohibit_entry;
3641         net->ipv6.ip6_blk_hole_entry->dst.path =
3642                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3643         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3644         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3645                          ip6_template_metrics, true);
3646 #endif
3647
3648         net->ipv6.sysctl.flush_delay = 0;
3649         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3650         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3651         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3652         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3653         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3654         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3655         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3656
3657         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3658
3659         ret = 0;
3660 out:
3661         return ret;
3662
3663 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3664 out_ip6_prohibit_entry:
3665         kfree(net->ipv6.ip6_prohibit_entry);
3666 out_ip6_null_entry:
3667         kfree(net->ipv6.ip6_null_entry);
3668 #endif
3669 out_ip6_dst_entries:
3670         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3671 out_ip6_dst_ops:
3672         goto out;
3673 }
3674
3675 static void __net_exit ip6_route_net_exit(struct net *net)
3676 {
3677         kfree(net->ipv6.ip6_null_entry);
3678 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3679         kfree(net->ipv6.ip6_prohibit_entry);
3680         kfree(net->ipv6.ip6_blk_hole_entry);
3681 #endif
3682         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3683 }
3684
3685 static int __net_init ip6_route_net_init_late(struct net *net)
3686 {
3687 #ifdef CONFIG_PROC_FS
3688         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3689         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3690 #endif
3691         return 0;
3692 }
3693
3694 static void __net_exit ip6_route_net_exit_late(struct net *net)
3695 {
3696 #ifdef CONFIG_PROC_FS
3697         remove_proc_entry("ipv6_route", net->proc_net);
3698         remove_proc_entry("rt6_stats", net->proc_net);
3699 #endif
3700 }
3701
3702 static struct pernet_operations ip6_route_net_ops = {
3703         .init = ip6_route_net_init,
3704         .exit = ip6_route_net_exit,
3705 };
3706
3707 static int __net_init ipv6_inetpeer_init(struct net *net)
3708 {
3709         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3710
3711         if (!bp)
3712                 return -ENOMEM;
3713         inet_peer_base_init(bp);
3714         net->ipv6.peers = bp;
3715         return 0;
3716 }
3717
3718 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3719 {
3720         struct inet_peer_base *bp = net->ipv6.peers;
3721
3722         net->ipv6.peers = NULL;
3723         inetpeer_invalidate_tree(bp);
3724         kfree(bp);
3725 }
3726
3727 static struct pernet_operations ipv6_inetpeer_ops = {
3728         .init   =       ipv6_inetpeer_init,
3729         .exit   =       ipv6_inetpeer_exit,
3730 };
3731
3732 static struct pernet_operations ip6_route_net_late_ops = {
3733         .init = ip6_route_net_init_late,
3734         .exit = ip6_route_net_exit_late,
3735 };
3736
3737 static struct notifier_block ip6_route_dev_notifier = {
3738         .notifier_call = ip6_route_dev_notify,
3739         .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
3740 };
3741
3742 void __init ip6_route_init_special_entries(void)
3743 {
3744         /* Registering of the loopback is done before this portion of code,
3745          * the loopback reference in rt6_info will not be taken, do it
3746          * manually for init_net */
3747         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3748         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3749   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3750         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3751         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3752         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3753         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3754   #endif
3755 }
3756
3757 int __init ip6_route_init(void)
3758 {
3759         int ret;
3760         int cpu;
3761
3762         ret = -ENOMEM;
3763         ip6_dst_ops_template.kmem_cachep =
3764                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3765                                   SLAB_HWCACHE_ALIGN, NULL);
3766         if (!ip6_dst_ops_template.kmem_cachep)
3767                 goto out;
3768
3769         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3770         if (ret)
3771                 goto out_kmem_cache;
3772
3773         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3774         if (ret)
3775                 goto out_dst_entries;
3776
3777         ret = register_pernet_subsys(&ip6_route_net_ops);
3778         if (ret)
3779                 goto out_register_inetpeer;
3780
3781         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3782
3783         ret = fib6_init();
3784         if (ret)
3785                 goto out_register_subsys;
3786
3787         ret = xfrm6_init();
3788         if (ret)
3789                 goto out_fib6_init;
3790
3791         ret = fib6_rules_init();
3792         if (ret)
3793                 goto xfrm6_init;
3794
3795         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3796         if (ret)
3797                 goto fib6_rules_init;
3798
3799         ret = -ENOBUFS;
3800         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3801             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3802             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3803                 goto out_register_late_subsys;
3804
3805         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3806         if (ret)
3807                 goto out_register_late_subsys;
3808
3809         for_each_possible_cpu(cpu) {
3810                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3811
3812                 INIT_LIST_HEAD(&ul->head);
3813                 spin_lock_init(&ul->lock);
3814         }
3815
3816 out:
3817         return ret;
3818
3819 out_register_late_subsys:
3820         unregister_pernet_subsys(&ip6_route_net_late_ops);
3821 fib6_rules_init:
3822         fib6_rules_cleanup();
3823 xfrm6_init:
3824         xfrm6_fini();
3825 out_fib6_init:
3826         fib6_gc_cleanup();
3827 out_register_subsys:
3828         unregister_pernet_subsys(&ip6_route_net_ops);
3829 out_register_inetpeer:
3830         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3831 out_dst_entries:
3832         dst_entries_destroy(&ip6_dst_blackhole_ops);
3833 out_kmem_cache:
3834         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3835         goto out;
3836 }
3837
3838 void ip6_route_cleanup(void)
3839 {
3840         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3841         unregister_pernet_subsys(&ip6_route_net_late_ops);
3842         fib6_rules_cleanup();
3843         xfrm6_fini();
3844         fib6_gc_cleanup();
3845         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3846         unregister_pernet_subsys(&ip6_route_net_ops);
3847         dst_entries_destroy(&ip6_dst_blackhole_ops);
3848         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3849 }