net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64 #include <net/l3mdev.h>
  65 #include <trace/events/fib6.h>
  66
  67 #include <asm/uaccess.h>
  68
  69 #ifdef CONFIG_SYSCTL
  70 #include <linux/sysctl.h>
  71 #endif
  72
  73 enum rt6_nud_state {
  74         RT6_NUD_FAIL_HARD = -3,
  75         RT6_NUD_FAIL_PROBE = -2,
  76         RT6_NUD_FAIL_DO_RR = -1,
  77         RT6_NUD_SUCCEED = 1
  78 };
  79
  80 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  81 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  82 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  83 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  84 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  85 static void             ip6_dst_destroy(struct dst_entry *);
  86 static void             ip6_dst_ifdown(struct dst_entry *,
  87                                        struct net_device *dev, int how);
  88 static int               ip6_dst_gc(struct dst_ops *ops);
  89
  90 static int              ip6_pkt_discard(struct sk_buff *skb);
  91 static int              ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  92 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  93 static int              ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  94 static void             ip6_link_failure(struct sk_buff *skb);
  95 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  96                                            struct sk_buff *skb, u32 mtu);
  97 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  98                                         struct sk_buff *skb);
  99 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
 100 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
 101
 102 #ifdef CONFIG_IPV6_ROUTE_INFO
 103 static struct rt6_info *rt6_add_route_info(struct net *net,
 104                                            const struct in6_addr *prefix, int prefixlen,
 105                                            const struct in6_addr *gwaddr, int ifindex,
 106                                            unsigned int pref);
 107 static struct rt6_info *rt6_get_route_info(struct net *net,
 108                                            const struct in6_addr *prefix, int prefixlen,
 109                                            const struct in6_addr *gwaddr, int ifindex);
 110 #endif
 111
 112 struct uncached_list {
 113         spinlock_t              lock;
 114         struct list_head        head;
 115 };
 116
 117 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 118
 119 static void rt6_uncached_list_add(struct rt6_info *rt)
 120 {
 121         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 122
 123         rt->dst.flags |= DST_NOCACHE;
 124         rt->rt6i_uncached_list = ul;
 125
 126         spin_lock_bh(&ul->lock);
 127         list_add_tail(&rt->rt6i_uncached, &ul->head);
 128         spin_unlock_bh(&ul->lock);
 129 }
 130
 131 static void rt6_uncached_list_del(struct rt6_info *rt)
 132 {
 133         if (!list_empty(&rt->rt6i_uncached)) {
 134                 struct uncached_list *ul = rt->rt6i_uncached_list;
 135
 136                 spin_lock_bh(&ul->lock);
 137                 list_del(&rt->rt6i_uncached);
 138                 spin_unlock_bh(&ul->lock);
 139         }
 140 }
 141
 142 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 143 {
 144         struct net_device *loopback_dev = net->loopback_dev;
 145         int cpu;
 146
 147         if (dev == loopback_dev)
 148                 return;
 149
 150         for_each_possible_cpu(cpu) {
 151                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 152                 struct rt6_info *rt;
 153
 154                 spin_lock_bh(&ul->lock);
 155                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 156                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 157                         struct net_device *rt_dev = rt->dst.dev;
 158
 159                         if (rt_idev->dev == dev) {
 160                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 161                                 in6_dev_put(rt_idev);
 162                         }
 163
 164                         if (rt_dev == dev) {
 165                                 rt->dst.dev = loopback_dev;
 166                                 dev_hold(rt->dst.dev);
 167                                 dev_put(rt_dev);
 168                         }
 169                 }
 170                 spin_unlock_bh(&ul->lock);
 171         }
 172 }
 173
 174 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 175 {
 176         return dst_metrics_write_ptr(rt->dst.from);
 177 }
 178
 179 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 180 {
 181         struct rt6_info *rt = (struct rt6_info *)dst;
 182
 183         if (rt->rt6i_flags & RTF_PCPU)
 184                 return rt6_pcpu_cow_metrics(rt);
 185         else if (rt->rt6i_flags & RTF_CACHE)
 186                 return NULL;
 187         else
 188                 return dst_cow_metrics_generic(dst, old);
 189 }
 190
 191 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 192                                              struct sk_buff *skb,
 193                                              const void *daddr)
 194 {
 195         struct in6_addr *p = &rt->rt6i_gateway;
 196
 197         if (!ipv6_addr_any(p))
 198                 return (const void *) p;
 199         else if (skb)
 200                 return &ipv6_hdr(skb)->daddr;
 201         return daddr;
 202 }
 203
 204 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 205                                           struct sk_buff *skb,
 206                                           const void *daddr)
 207 {
 208         struct rt6_info *rt = (struct rt6_info *) dst;
 209         struct neighbour *n;
 210
 211         daddr = choose_neigh_daddr(rt, skb, daddr);
 212         n = __ipv6_neigh_lookup(dst->dev, daddr);
 213         if (n)
 214                 return n;
 215         return neigh_create(&nd_tbl, daddr, dst->dev);
 216 }
 217
 218 static struct dst_ops ip6_dst_ops_template = {
 219         .family                 =       AF_INET6,
 220         .gc                     =       ip6_dst_gc,
 221         .gc_thresh              =       1024,
 222         .check                  =       ip6_dst_check,
 223         .default_advmss         =       ip6_default_advmss,
 224         .mtu                    =       ip6_mtu,
 225         .cow_metrics            =       ipv6_cow_metrics,
 226         .destroy                =       ip6_dst_destroy,
 227         .ifdown                 =       ip6_dst_ifdown,
 228         .negative_advice        =       ip6_negative_advice,
 229         .link_failure           =       ip6_link_failure,
 230         .update_pmtu            =       ip6_rt_update_pmtu,
 231         .redirect               =       rt6_do_redirect,
 232         .local_out              =       __ip6_local_out,
 233         .neigh_lookup           =       ip6_neigh_lookup,
 234 };
 235
 236 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 237 {
 238         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 239
 240         return mtu ? : dst->dev->mtu;
 241 }
 242
 243 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 244                                          struct sk_buff *skb, u32 mtu)
 245 {
 246 }
 247
 248 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 249                                       struct sk_buff *skb)
 250 {
 251 }
 252
 253 static struct dst_ops ip6_dst_blackhole_ops = {
 254         .family                 =       AF_INET6,
 255         .destroy                =       ip6_dst_destroy,
 256         .check                  =       ip6_dst_check,
 257         .mtu                    =       ip6_blackhole_mtu,
 258         .default_advmss         =       ip6_default_advmss,
 259         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 260         .redirect               =       ip6_rt_blackhole_redirect,
 261         .cow_metrics            =       dst_cow_metrics_generic,
 262         .neigh_lookup           =       ip6_neigh_lookup,
 263 };
 264
 265 static const u32 ip6_template_metrics[RTAX_MAX] = {
 266         [RTAX_HOPLIMIT - 1] = 0,
 267 };
 268
 269 static const struct rt6_info ip6_null_entry_template = {
 270         .dst = {
 271                 .__refcnt       = ATOMIC_INIT(1),
 272                 .__use          = 1,
 273                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 274                 .error          = -ENETUNREACH,
 275                 .input          = ip6_pkt_discard,
 276                 .output         = ip6_pkt_discard_out,
 277         },
 278         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 279         .rt6i_protocol  = RTPROT_KERNEL,
 280         .rt6i_metric    = ~(u32) 0,
 281         .rt6i_ref       = ATOMIC_INIT(1),
 282 };
 283
 284 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 285
 286 static const struct rt6_info ip6_prohibit_entry_template = {
 287         .dst = {
 288                 .__refcnt       = ATOMIC_INIT(1),
 289                 .__use          = 1,
 290                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 291                 .error          = -EACCES,
 292                 .input          = ip6_pkt_prohibit,
 293                 .output         = ip6_pkt_prohibit_out,
 294         },
 295         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 296         .rt6i_protocol  = RTPROT_KERNEL,
 297         .rt6i_metric    = ~(u32) 0,
 298         .rt6i_ref       = ATOMIC_INIT(1),
 299 };
 300
 301 static const struct rt6_info ip6_blk_hole_entry_template = {
 302         .dst = {
 303                 .__refcnt       = ATOMIC_INIT(1),
 304                 .__use          = 1,
 305                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 306                 .error          = -EINVAL,
 307                 .input          = dst_discard,
 308                 .output         = dst_discard_out,
 309         },
 310         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 311         .rt6i_protocol  = RTPROT_KERNEL,
 312         .rt6i_metric    = ~(u32) 0,
 313         .rt6i_ref       = ATOMIC_INIT(1),
 314 };
 315
 316 #endif
 317
 318 static void rt6_info_init(struct rt6_info *rt)
 319 {
 320         struct dst_entry *dst = &rt->dst;
 321
 322         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 323         INIT_LIST_HEAD(&rt->rt6i_siblings);
 324         INIT_LIST_HEAD(&rt->rt6i_uncached);
 325 }
 326
 327 /* allocate dst with ip6_dst_ops */
 328 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 329                                         struct net_device *dev,
 330                                         int flags)
 331 {
 332         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 333                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 334
 335         if (rt)
 336                 rt6_info_init(rt);
 337
 338         return rt;
 339 }
 340
 341 struct rt6_info *ip6_dst_alloc(struct net *net,
 342                                struct net_device *dev,
 343                                int flags)
 344 {
 345         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 346
 347         if (rt) {
 348                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 349                 if (rt->rt6i_pcpu) {
 350                         int cpu;
 351
 352                         for_each_possible_cpu(cpu) {
 353                                 struct rt6_info **p;
 354
 355                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 356                                 /* no one shares rt */
 357                                 *p =  NULL;
 358                         }
 359                 } else {
 360                         dst_destroy((struct dst_entry *)rt);
 361                         return NULL;
 362                 }
 363         }
 364
 365         return rt;
 366 }
 367 EXPORT_SYMBOL(ip6_dst_alloc);
 368
 369 static void ip6_dst_destroy(struct dst_entry *dst)
 370 {
 371         struct rt6_info *rt = (struct rt6_info *)dst;
 372         struct dst_entry *from = dst->from;
 373         struct inet6_dev *idev;
 374
 375         dst_destroy_metrics_generic(dst);
 376         free_percpu(rt->rt6i_pcpu);
 377         rt6_uncached_list_del(rt);
 378
 379         idev = rt->rt6i_idev;
 380         if (idev) {
 381                 rt->rt6i_idev = NULL;
 382                 in6_dev_put(idev);
 383         }
 384
 385         dst->from = NULL;
 386         dst_release(from);
 387 }
 388
 389 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 390                            int how)
 391 {
 392         struct rt6_info *rt = (struct rt6_info *)dst;
 393         struct inet6_dev *idev = rt->rt6i_idev;
 394         struct net_device *loopback_dev =
 395                 dev_net(dev)->loopback_dev;
 396
 397         if (dev != loopback_dev) {
 398                 if (idev && idev->dev == dev) {
 399                         struct inet6_dev *loopback_idev =
 400                                 in6_dev_get(loopback_dev);
 401                         if (loopback_idev) {
 402                                 rt->rt6i_idev = loopback_idev;
 403                                 in6_dev_put(idev);
 404                         }
 405                 }
 406         }
 407 }
 408
 409 static bool __rt6_check_expired(const struct rt6_info *rt)
 410 {
 411         if (rt->rt6i_flags & RTF_EXPIRES)
 412                 return time_after(jiffies, rt->dst.expires);
 413         else
 414                 return false;
 415 }
 416
 417 static bool rt6_check_expired(const struct rt6_info *rt)
 418 {
 419         if (rt->rt6i_flags & RTF_EXPIRES) {
 420                 if (time_after(jiffies, rt->dst.expires))
 421                         return true;
 422         } else if (rt->dst.from) {
 423                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 424         }
 425         return false;
 426 }
 427
 428 /* Multipath route selection:
 429  *   Hash based function using packet header and flowlabel.
 430  * Adapted from fib_info_hashfn()
 431  */
 432 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 433                                const struct flowi6 *fl6)
 434 {
 435         return get_hash_from_flowi6(fl6) % candidate_count;
 436 }
 437
 438 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 439                                              struct flowi6 *fl6, int oif,
 440                                              int strict)
 441 {
 442         struct rt6_info *sibling, *next_sibling;
 443         int route_choosen;
 444
 445         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 446         /* Don't change the route, if route_choosen == 0
 447          * (siblings does not include ourself)
 448          */
 449         if (route_choosen)
 450                 list_for_each_entry_safe(sibling, next_sibling,
 451                                 &match->rt6i_siblings, rt6i_siblings) {
 452                         route_choosen--;
 453                         if (route_choosen == 0) {
 454                                 if (rt6_score_route(sibling, oif, strict) < 0)
 455                                         break;
 456                                 match = sibling;
 457                                 break;
 458                         }
 459                 }
 460         return match;
 461 }
 462
 463 /*
 464  *      Route lookup. Any table->tb6_lock is implied.
 465  */
 466
 467 static inline struct rt6_info *rt6_device_match(struct net *net,
 468                                                     struct rt6_info *rt,
 469                                                     const struct in6_addr *saddr,
 470                                                     int oif,
 471                                                     int flags)
 472 {
 473         struct rt6_info *local = NULL;
 474         struct rt6_info *sprt;
 475
 476         if (!oif && ipv6_addr_any(saddr))
 477                 goto out;
 478
 479         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 480                 struct net_device *dev = sprt->dst.dev;
 481
 482                 if (oif) {
 483                         if (dev->ifindex == oif)
 484                                 return sprt;
 485                         if (dev->flags & IFF_LOOPBACK) {
 486                                 if (!sprt->rt6i_idev ||
 487                                     sprt->rt6i_idev->dev->ifindex != oif) {
 488                                         if (flags & RT6_LOOKUP_F_IFACE)
 489                                                 continue;
 490                                         if (local &&
 491                                             local->rt6i_idev->dev->ifindex == oif)
 492                                                 continue;
 493                                 }
 494                                 local = sprt;
 495                         }
 496                 } else {
 497                         if (ipv6_chk_addr(net, saddr, dev,
 498                                           flags & RT6_LOOKUP_F_IFACE))
 499                                 return sprt;
 500                 }
 501         }
 502
 503         if (oif) {
 504                 if (local)
 505                         return local;
 506
 507                 if (flags & RT6_LOOKUP_F_IFACE)
 508                         return net->ipv6.ip6_null_entry;
 509         }
 510 out:
 511         return rt;
 512 }
 513
 514 #ifdef CONFIG_IPV6_ROUTER_PREF
 515 struct __rt6_probe_work {
 516         struct work_struct work;
 517         struct in6_addr target;
 518         struct net_device *dev;
 519 };
 520
 521 static void rt6_probe_deferred(struct work_struct *w)
 522 {
 523         struct in6_addr mcaddr;
 524         struct __rt6_probe_work *work =
 525                 container_of(w, struct __rt6_probe_work, work);
 526
 527         addrconf_addr_solict_mult(&work->target, &mcaddr);
 528         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL);
 529         dev_put(work->dev);
 530         kfree(work);
 531 }
 532
 533 static void rt6_probe(struct rt6_info *rt)
 534 {
 535         struct __rt6_probe_work *work;
 536         struct neighbour *neigh;
 537         /*
 538          * Okay, this does not seem to be appropriate
 539          * for now, however, we need to check if it
 540          * is really so; aka Router Reachability Probing.
 541          *
 542          * Router Reachability Probe MUST be rate-limited
 543          * to no more than one per minute.
 544          */
 545         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 546                 return;
 547         rcu_read_lock_bh();
 548         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 549         if (neigh) {
 550                 if (neigh->nud_state & NUD_VALID)
 551                         goto out;
 552
 553                 work = NULL;
 554                 write_lock(&neigh->lock);
 555                 if (!(neigh->nud_state & NUD_VALID) &&
 556                     time_after(jiffies,
 557                                neigh->updated +
 558                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 559                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 560                         if (work)
 561                                 __neigh_set_probe_once(neigh);
 562                 }
 563                 write_unlock(&neigh->lock);
 564         } else {
 565                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 566         }
 567
 568         if (work) {
 569                 INIT_WORK(&work->work, rt6_probe_deferred);
 570                 work->target = rt->rt6i_gateway;
 571                 dev_hold(rt->dst.dev);
 572                 work->dev = rt->dst.dev;
 573                 schedule_work(&work->work);
 574         }
 575
 576 out:
 577         rcu_read_unlock_bh();
 578 }
 579 #else
 580 static inline void rt6_probe(struct rt6_info *rt)
 581 {
 582 }
 583 #endif
 584
 585 /*
 586  * Default Router Selection (RFC 2461 6.3.6)
 587  */
 588 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 589 {
 590         struct net_device *dev = rt->dst.dev;
 591         if (!oif || dev->ifindex == oif)
 592                 return 2;
 593         if ((dev->flags & IFF_LOOPBACK) &&
 594             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 595                 return 1;
 596         return 0;
 597 }
 598
 599 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 600 {
 601         struct neighbour *neigh;
 602         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 603
 604         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 605             !(rt->rt6i_flags & RTF_GATEWAY))
 606                 return RT6_NUD_SUCCEED;
 607
 608         rcu_read_lock_bh();
 609         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 610         if (neigh) {
 611                 read_lock(&neigh->lock);
 612                 if (neigh->nud_state & NUD_VALID)
 613                         ret = RT6_NUD_SUCCEED;
 614 #ifdef CONFIG_IPV6_ROUTER_PREF
 615                 else if (!(neigh->nud_state & NUD_FAILED))
 616                         ret = RT6_NUD_SUCCEED;
 617                 else
 618                         ret = RT6_NUD_FAIL_PROBE;
 619 #endif
 620                 read_unlock(&neigh->lock);
 621         } else {
 622                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 623                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 624         }
 625         rcu_read_unlock_bh();
 626
 627         return ret;
 628 }
 629
 630 static int rt6_score_route(struct rt6_info *rt, int oif,
 631                            int strict)
 632 {
 633         int m;
 634
 635         m = rt6_check_dev(rt, oif);
 636         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 637                 return RT6_NUD_FAIL_HARD;
 638 #ifdef CONFIG_IPV6_ROUTER_PREF
 639         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 640 #endif
 641         if (strict & RT6_LOOKUP_F_REACHABLE) {
 642                 int n = rt6_check_neigh(rt);
 643                 if (n < 0)
 644                         return n;
 645         }
 646         return m;
 647 }
 648
 649 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 650                                    int *mpri, struct rt6_info *match,
 651                                    bool *do_rr)
 652 {
 653         int m;
 654         bool match_do_rr = false;
 655         struct inet6_dev *idev = rt->rt6i_idev;
 656         struct net_device *dev = rt->dst.dev;
 657
 658         if (dev && !netif_carrier_ok(dev) &&
 659             idev->cnf.ignore_routes_with_linkdown)
 660                 goto out;
 661
 662         if (rt6_check_expired(rt))
 663                 goto out;
 664
 665         m = rt6_score_route(rt, oif, strict);
 666         if (m == RT6_NUD_FAIL_DO_RR) {
 667                 match_do_rr = true;
 668                 m = 0; /* lowest valid score */
 669         } else if (m == RT6_NUD_FAIL_HARD) {
 670                 goto out;
 671         }
 672
 673         if (strict & RT6_LOOKUP_F_REACHABLE)
 674                 rt6_probe(rt);
 675
 676         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 677         if (m > *mpri) {
 678                 *do_rr = match_do_rr;
 679                 *mpri = m;
 680                 match = rt;
 681         }
 682 out:
 683         return match;
 684 }
 685
 686 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 687                                      struct rt6_info *rr_head,
 688                                      u32 metric, int oif, int strict,
 689                                      bool *do_rr)
 690 {
 691         struct rt6_info *rt, *match, *cont;
 692         int mpri = -1;
 693
 694         match = NULL;
 695         cont = NULL;
 696         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 697                 if (rt->rt6i_metric != metric) {
 698                         cont = rt;
 699                         break;
 700                 }
 701
 702                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 703         }
 704
 705         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 706                 if (rt->rt6i_metric != metric) {
 707                         cont = rt;
 708                         break;
 709                 }
 710
 711                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 712         }
 713
 714         if (match || !cont)
 715                 return match;
 716
 717         for (rt = cont; rt; rt = rt->dst.rt6_next)
 718                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 719
 720         return match;
 721 }
 722
 723 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 724 {
 725         struct rt6_info *match, *rt0;
 726         struct net *net;
 727         bool do_rr = false;
 728
 729         rt0 = fn->rr_ptr;
 730         if (!rt0)
 731                 fn->rr_ptr = rt0 = fn->leaf;
 732
 733         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 734                              &do_rr);
 735
 736         if (do_rr) {
 737                 struct rt6_info *next = rt0->dst.rt6_next;
 738
 739                 /* no entries matched; do round-robin */
 740                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 741                         next = fn->leaf;
 742
 743                 if (next != rt0)
 744                         fn->rr_ptr = next;
 745         }
 746
 747         net = dev_net(rt0->dst.dev);
 748         return match ? match : net->ipv6.ip6_null_entry;
 749 }
 750
 751 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 752 {
 753         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 754 }
 755
 756 #ifdef CONFIG_IPV6_ROUTE_INFO
 757 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 758                   const struct in6_addr *gwaddr)
 759 {
 760         struct net *net = dev_net(dev);
 761         struct route_info *rinfo = (struct route_info *) opt;
 762         struct in6_addr prefix_buf, *prefix;
 763         unsigned int pref;
 764         unsigned long lifetime;
 765         struct rt6_info *rt;
 766
 767         if (len < sizeof(struct route_info)) {
 768                 return -EINVAL;
 769         }
 770
 771         /* Sanity check for prefix_len and length */
 772         if (rinfo->length > 3) {
 773                 return -EINVAL;
 774         } else if (rinfo->prefix_len > 128) {
 775                 return -EINVAL;
 776         } else if (rinfo->prefix_len > 64) {
 777                 if (rinfo->length < 2) {
 778                         return -EINVAL;
 779                 }
 780         } else if (rinfo->prefix_len > 0) {
 781                 if (rinfo->length < 1) {
 782                         return -EINVAL;
 783                 }
 784         }
 785
 786         pref = rinfo->route_pref;
 787         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 788                 return -EINVAL;
 789
 790         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 791
 792         if (rinfo->length == 3)
 793                 prefix = (struct in6_addr *)rinfo->prefix;
 794         else {
 795                 /* this function is safe */
 796                 ipv6_addr_prefix(&prefix_buf,
 797                                  (struct in6_addr *)rinfo->prefix,
 798                                  rinfo->prefix_len);
 799                 prefix = &prefix_buf;
 800         }
 801
 802         if (rinfo->prefix_len == 0)
 803                 rt = rt6_get_dflt_router(gwaddr, dev);
 804         else
 805                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 806                                         gwaddr, dev->ifindex);
 807
 808         if (rt && !lifetime) {
 809                 ip6_del_rt(rt);
 810                 rt = NULL;
 811         }
 812
 813         if (!rt && lifetime)
 814                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 815                                         pref);
 816         else if (rt)
 817                 rt->rt6i_flags = RTF_ROUTEINFO |
 818                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 819
 820         if (rt) {
 821                 if (!addrconf_finite_timeout(lifetime))
 822                         rt6_clean_expires(rt);
 823                 else
 824                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 825
 826                 ip6_rt_put(rt);
 827         }
 828         return 0;
 829 }
 830 #endif
 831
 832 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 833                                         struct in6_addr *saddr)
 834 {
 835         struct fib6_node *pn;
 836         while (1) {
 837                 if (fn->fn_flags & RTN_TL_ROOT)
 838                         return NULL;
 839                 pn = fn->parent;
 840                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 841                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 842                 else
 843                         fn = pn;
 844                 if (fn->fn_flags & RTN_RTINFO)
 845                         return fn;
 846         }
 847 }
 848
 849 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 850                                              struct fib6_table *table,
 851                                              struct flowi6 *fl6, int flags)
 852 {
 853         struct fib6_node *fn;
 854         struct rt6_info *rt;
 855
 856         read_lock_bh(&table->tb6_lock);
 857         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 858 restart:
 859         rt = fn->leaf;
 860         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 861         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 862                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 863         if (rt == net->ipv6.ip6_null_entry) {
 864                 fn = fib6_backtrack(fn, &fl6->saddr);
 865                 if (fn)
 866                         goto restart;
 867         }
 868         dst_use(&rt->dst, jiffies);
 869         read_unlock_bh(&table->tb6_lock);
 870
 871         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
 872
 873         return rt;
 874
 875 }
 876
 877 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 878                                     int flags)
 879 {
 880         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 881 }
 882 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 883
 884 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 885                             const struct in6_addr *saddr, int oif, int strict)
 886 {
 887         struct flowi6 fl6 = {
 888                 .flowi6_oif = oif,
 889                 .daddr = *daddr,
 890         };
 891         struct dst_entry *dst;
 892         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 893
 894         if (saddr) {
 895                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 896                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 897         }
 898
 899         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 900         if (dst->error == 0)
 901                 return (struct rt6_info *) dst;
 902
 903         dst_release(dst);
 904
 905         return NULL;
 906 }
 907 EXPORT_SYMBOL(rt6_lookup);
 908
 909 /* ip6_ins_rt is called with FREE table->tb6_lock.
 910    It takes new route entry, the addition fails by any reason the
 911    route is freed. In any case, if caller does not hold it, it may
 912    be destroyed.
 913  */
 914
 915 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 916                         struct mx6_config *mxc)
 917 {
 918         int err;
 919         struct fib6_table *table;
 920
 921         table = rt->rt6i_table;
 922         write_lock_bh(&table->tb6_lock);
 923         err = fib6_add(&table->tb6_root, rt, info, mxc);
 924         write_unlock_bh(&table->tb6_lock);
 925
 926         return err;
 927 }
 928
 929 int ip6_ins_rt(struct rt6_info *rt)
 930 {
 931         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 932         struct mx6_config mxc = { .mx = NULL, };
 933
 934         return __ip6_ins_rt(rt, &info, &mxc);
 935 }
 936
 937 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 938                                            const struct in6_addr *daddr,
 939                                            const struct in6_addr *saddr)
 940 {
 941         struct rt6_info *rt;
 942
 943         /*
 944          *      Clone the route.
 945          */
 946
 947         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 948                 ort = (struct rt6_info *)ort->dst.from;
 949
 950         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 951
 952         if (!rt)
 953                 return NULL;
 954
 955         ip6_rt_copy_init(rt, ort);
 956         rt->rt6i_flags |= RTF_CACHE;
 957         rt->rt6i_metric = 0;
 958         rt->dst.flags |= DST_HOST;
 959         rt->rt6i_dst.addr = *daddr;
 960         rt->rt6i_dst.plen = 128;
 961
 962         if (!rt6_is_gw_or_nonexthop(ort)) {
 963                 if (ort->rt6i_dst.plen != 128 &&
 964                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 965                         rt->rt6i_flags |= RTF_ANYCAST;
 966 #ifdef CONFIG_IPV6_SUBTREES
 967                 if (rt->rt6i_src.plen && saddr) {
 968                         rt->rt6i_src.addr = *saddr;
 969                         rt->rt6i_src.plen = 128;
 970                 }
 971 #endif
 972         }
 973
 974         return rt;
 975 }
 976
 977 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 978 {
 979         struct rt6_info *pcpu_rt;
 980
 981         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 982                                   rt->dst.dev, rt->dst.flags);
 983
 984         if (!pcpu_rt)
 985                 return NULL;
 986         ip6_rt_copy_init(pcpu_rt, rt);
 987         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 988         pcpu_rt->rt6i_flags |= RTF_PCPU;
 989         return pcpu_rt;
 990 }
 991
 992 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 993 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 994 {
 995         struct rt6_info *pcpu_rt, **p;
 996
 997         p = this_cpu_ptr(rt->rt6i_pcpu);
 998         pcpu_rt = *p;
 999
1000         if (pcpu_rt) {
1001                 dst_hold(&pcpu_rt->dst);
1002                 rt6_dst_from_metrics_check(pcpu_rt);
1003         }
1004         return pcpu_rt;
1005 }
1006
1007 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1008 {
1009         struct fib6_table *table = rt->rt6i_table;
1010         struct rt6_info *pcpu_rt, *prev, **p;
1011
1012         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1013         if (!pcpu_rt) {
1014                 struct net *net = dev_net(rt->dst.dev);
1015
1016                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1017                 return net->ipv6.ip6_null_entry;
1018         }
1019
1020         read_lock_bh(&table->tb6_lock);
1021         if (rt->rt6i_pcpu) {
1022                 p = this_cpu_ptr(rt->rt6i_pcpu);
1023                 prev = cmpxchg(p, NULL, pcpu_rt);
1024                 if (prev) {
1025                         /* If someone did it before us, return prev instead */
1026                         dst_destroy(&pcpu_rt->dst);
1027                         pcpu_rt = prev;
1028                 }
1029         } else {
1030                 /* rt has been removed from the fib6 tree
1031                  * before we have a chance to acquire the read_lock.
1032                  * In this case, don't brother to create a pcpu rt
1033                  * since rt is going away anyway.  The next
1034                  * dst_check() will trigger a re-lookup.
1035                  */
1036                 dst_destroy(&pcpu_rt->dst);
1037                 pcpu_rt = rt;
1038         }
1039         dst_hold(&pcpu_rt->dst);
1040         rt6_dst_from_metrics_check(pcpu_rt);
1041         read_unlock_bh(&table->tb6_lock);
1042         return pcpu_rt;
1043 }
1044
1045 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1046                                       struct flowi6 *fl6, int flags)
1047 {
1048         struct fib6_node *fn, *saved_fn;
1049         struct rt6_info *rt;
1050         int strict = 0;
1051
1052         strict |= flags & RT6_LOOKUP_F_IFACE;
1053         if (net->ipv6.devconf_all->forwarding == 0)
1054                 strict |= RT6_LOOKUP_F_REACHABLE;
1055
1056         read_lock_bh(&table->tb6_lock);
1057
1058         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1059         saved_fn = fn;
1060
1061         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1062                 oif = 0;
1063
1064 redo_rt6_select:
1065         rt = rt6_select(fn, oif, strict);
1066         if (rt->rt6i_nsiblings)
1067                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1068         if (rt == net->ipv6.ip6_null_entry) {
1069                 fn = fib6_backtrack(fn, &fl6->saddr);
1070                 if (fn)
1071                         goto redo_rt6_select;
1072                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1073                         /* also consider unreachable route */
1074                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1075                         fn = saved_fn;
1076                         goto redo_rt6_select;
1077                 }
1078         }
1079
1080
1081         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1082                 dst_use(&rt->dst, jiffies);
1083                 read_unlock_bh(&table->tb6_lock);
1084
1085                 rt6_dst_from_metrics_check(rt);
1086
1087                 trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1088                 return rt;
1089         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1090                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1091                 /* Create a RTF_CACHE clone which will not be
1092                  * owned by the fib6 tree.  It is for the special case where
1093                  * the daddr in the skb during the neighbor look-up is different
1094                  * from the fl6->daddr used to look-up route here.
1095                  */
1096
1097                 struct rt6_info *uncached_rt;
1098
1099                 dst_use(&rt->dst, jiffies);
1100                 read_unlock_bh(&table->tb6_lock);
1101
1102                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1103                 dst_release(&rt->dst);
1104
1105                 if (uncached_rt)
1106                         rt6_uncached_list_add(uncached_rt);
1107                 else
1108                         uncached_rt = net->ipv6.ip6_null_entry;
1109
1110                 dst_hold(&uncached_rt->dst);
1111
1112                 trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6);
1113                 return uncached_rt;
1114
1115         } else {
1116                 /* Get a percpu copy */
1117
1118                 struct rt6_info *pcpu_rt;
1119
1120                 rt->dst.lastuse = jiffies;
1121                 rt->dst.__use++;
1122                 pcpu_rt = rt6_get_pcpu_route(rt);
1123
1124                 if (pcpu_rt) {
1125                         read_unlock_bh(&table->tb6_lock);
1126                 } else {
1127                         /* We have to do the read_unlock first
1128                          * because rt6_make_pcpu_route() may trigger
1129                          * ip6_dst_gc() which will take the write_lock.
1130                          */
1131                         dst_hold(&rt->dst);
1132                         read_unlock_bh(&table->tb6_lock);
1133                         pcpu_rt = rt6_make_pcpu_route(rt);
1134                         dst_release(&rt->dst);
1135                 }
1136
1137                 trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6);
1138                 return pcpu_rt;
1139
1140         }
1141 }
1142
1143 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1144                                             struct flowi6 *fl6, int flags)
1145 {
1146         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1147 }
1148
1149 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1150                                                 struct net_device *dev,
1151                                                 struct flowi6 *fl6, int flags)
1152 {
1153         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1154                 flags |= RT6_LOOKUP_F_IFACE;
1155
1156         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1157 }
1158
1159 void ip6_route_input(struct sk_buff *skb)
1160 {
1161         const struct ipv6hdr *iph = ipv6_hdr(skb);
1162         struct net *net = dev_net(skb->dev);
1163         int flags = RT6_LOOKUP_F_HAS_SADDR;
1164         struct ip_tunnel_info *tun_info;
1165         struct flowi6 fl6 = {
1166                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1167                 .daddr = iph->daddr,
1168                 .saddr = iph->saddr,
1169                 .flowlabel = ip6_flowinfo(iph),
1170                 .flowi6_mark = skb->mark,
1171                 .flowi6_proto = iph->nexthdr,
1172         };
1173
1174         tun_info = skb_tunnel_info(skb);
1175         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1176                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1177         skb_dst_drop(skb);
1178         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1179 }
1180
1181 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1182                                              struct flowi6 *fl6, int flags)
1183 {
1184         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1185 }
1186
1187 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1188                                          struct flowi6 *fl6, int flags)
1189 {
1190         struct dst_entry *dst;
1191         bool any_src;
1192
1193         dst = l3mdev_rt6_dst_by_oif(net, fl6);
1194         if (dst)
1195                 return dst;
1196
1197         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1198
1199         any_src = ipv6_addr_any(&fl6->saddr);
1200         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1201             (fl6->flowi6_oif && any_src))
1202                 flags |= RT6_LOOKUP_F_IFACE;
1203
1204         if (!any_src)
1205                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1206         else if (sk)
1207                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1208
1209         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1210 }
1211 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1212
1213 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1214 {
1215         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1216         struct dst_entry *new = NULL;
1217
1218         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1219         if (rt) {
1220                 rt6_info_init(rt);
1221
1222                 new = &rt->dst;
1223                 new->__use = 1;
1224                 new->input = dst_discard;
1225                 new->output = dst_discard_out;
1226
1227                 dst_copy_metrics(new, &ort->dst);
1228                 rt->rt6i_idev = ort->rt6i_idev;
1229                 if (rt->rt6i_idev)
1230                         in6_dev_hold(rt->rt6i_idev);
1231
1232                 rt->rt6i_gateway = ort->rt6i_gateway;
1233                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1234                 rt->rt6i_metric = 0;
1235
1236                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1237 #ifdef CONFIG_IPV6_SUBTREES
1238                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1239 #endif
1240
1241                 dst_free(new);
1242         }
1243
1244         dst_release(dst_orig);
1245         return new ? new : ERR_PTR(-ENOMEM);
1246 }
1247
1248 /*
1249  *      Destination cache support functions
1250  */
1251
1252 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1253 {
1254         if (rt->dst.from &&
1255             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1256                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1257 }
1258
1259 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1260 {
1261         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1262                 return NULL;
1263
1264         if (rt6_check_expired(rt))
1265                 return NULL;
1266
1267         return &rt->dst;
1268 }
1269
1270 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1271 {
1272         if (!__rt6_check_expired(rt) &&
1273             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1274             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1275                 return &rt->dst;
1276         else
1277                 return NULL;
1278 }
1279
1280 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1281 {
1282         struct rt6_info *rt;
1283
1284         rt = (struct rt6_info *) dst;
1285
1286         /* All IPV6 dsts are created with ->obsolete set to the value
1287          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1288          * into this function always.
1289          */
1290
1291         rt6_dst_from_metrics_check(rt);
1292
1293         if (rt->rt6i_flags & RTF_PCPU ||
1294             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1295                 return rt6_dst_from_check(rt, cookie);
1296         else
1297                 return rt6_check(rt, cookie);
1298 }
1299
1300 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1301 {
1302         struct rt6_info *rt = (struct rt6_info *) dst;
1303
1304         if (rt) {
1305                 if (rt->rt6i_flags & RTF_CACHE) {
1306                         if (rt6_check_expired(rt)) {
1307                                 ip6_del_rt(rt);
1308                                 dst = NULL;
1309                         }
1310                 } else {
1311                         dst_release(dst);
1312                         dst = NULL;
1313                 }
1314         }
1315         return dst;
1316 }
1317
1318 static void ip6_link_failure(struct sk_buff *skb)
1319 {
1320         struct rt6_info *rt;
1321
1322         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1323
1324         rt = (struct rt6_info *) skb_dst(skb);
1325         if (rt) {
1326                 if (rt->rt6i_flags & RTF_CACHE) {
1327                         dst_hold(&rt->dst);
1328                         ip6_del_rt(rt);
1329                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1330                         rt->rt6i_node->fn_sernum = -1;
1331                 }
1332         }
1333 }
1334
1335 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1336 {
1337         struct net *net = dev_net(rt->dst.dev);
1338
1339         rt->rt6i_flags |= RTF_MODIFIED;
1340         rt->rt6i_pmtu = mtu;
1341         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1342 }
1343
1344 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1345 {
1346         return !(rt->rt6i_flags & RTF_CACHE) &&
1347                 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1348 }
1349
1350 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1351                                  const struct ipv6hdr *iph, u32 mtu)
1352 {
1353         struct rt6_info *rt6 = (struct rt6_info *)dst;
1354
1355         if (rt6->rt6i_flags & RTF_LOCAL)
1356                 return;
1357
1358         dst_confirm(dst);
1359         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1360         if (mtu >= dst_mtu(dst))
1361                 return;
1362
1363         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1364                 rt6_do_update_pmtu(rt6, mtu);
1365         } else {
1366                 const struct in6_addr *daddr, *saddr;
1367                 struct rt6_info *nrt6;
1368
1369                 if (iph) {
1370                         daddr = &iph->daddr;
1371                         saddr = &iph->saddr;
1372                 } else if (sk) {
1373                         daddr = &sk->sk_v6_daddr;
1374                         saddr = &inet6_sk(sk)->saddr;
1375                 } else {
1376                         return;
1377                 }
1378                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1379                 if (nrt6) {
1380                         rt6_do_update_pmtu(nrt6, mtu);
1381
1382                         /* ip6_ins_rt(nrt6) will bump the
1383                          * rt6->rt6i_node->fn_sernum
1384                          * which will fail the next rt6_check() and
1385                          * invalidate the sk->sk_dst_cache.
1386                          */
1387                         ip6_ins_rt(nrt6);
1388                 }
1389         }
1390 }
1391
1392 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1393                                struct sk_buff *skb, u32 mtu)
1394 {
1395         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1396 }
1397
1398 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1399                      int oif, u32 mark)
1400 {
1401         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1402         struct dst_entry *dst;
1403         struct flowi6 fl6;
1404
1405         memset(&fl6, 0, sizeof(fl6));
1406         fl6.flowi6_oif = oif;
1407         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1408         fl6.daddr = iph->daddr;
1409         fl6.saddr = iph->saddr;
1410         fl6.flowlabel = ip6_flowinfo(iph);
1411
1412         dst = ip6_route_output(net, NULL, &fl6);
1413         if (!dst->error)
1414                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1415         dst_release(dst);
1416 }
1417 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1418
1419 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1420 {
1421         struct dst_entry *dst;
1422
1423         ip6_update_pmtu(skb, sock_net(sk), mtu,
1424                         sk->sk_bound_dev_if, sk->sk_mark);
1425
1426         dst = __sk_dst_get(sk);
1427         if (!dst || !dst->obsolete ||
1428             dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
1429                 return;
1430
1431         bh_lock_sock(sk);
1432         if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1433                 ip6_datagram_dst_update(sk, false);
1434         bh_unlock_sock(sk);
1435 }
1436 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1437
1438 /* Handle redirects */
1439 struct ip6rd_flowi {
1440         struct flowi6 fl6;
1441         struct in6_addr gateway;
1442 };
1443
1444 static struct rt6_info *__ip6_route_redirect(struct net *net,
1445                                              struct fib6_table *table,
1446                                              struct flowi6 *fl6,
1447                                              int flags)
1448 {
1449         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1450         struct rt6_info *rt;
1451         struct fib6_node *fn;
1452
1453         /* Get the "current" route for this destination and
1454          * check if the redirect has come from approriate router.
1455          *
1456          * RFC 4861 specifies that redirects should only be
1457          * accepted if they come from the nexthop to the target.
1458          * Due to the way the routes are chosen, this notion
1459          * is a bit fuzzy and one might need to check all possible
1460          * routes.
1461          */
1462
1463         read_lock_bh(&table->tb6_lock);
1464         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1465 restart:
1466         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1467                 if (rt6_check_expired(rt))
1468                         continue;
1469                 if (rt->dst.error)
1470                         break;
1471                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1472                         continue;
1473                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1474                         continue;
1475                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1476                         continue;
1477                 break;
1478         }
1479
1480         if (!rt)
1481                 rt = net->ipv6.ip6_null_entry;
1482         else if (rt->dst.error) {
1483                 rt = net->ipv6.ip6_null_entry;
1484                 goto out;
1485         }
1486
1487         if (rt == net->ipv6.ip6_null_entry) {
1488                 fn = fib6_backtrack(fn, &fl6->saddr);
1489                 if (fn)
1490                         goto restart;
1491         }
1492
1493 out:
1494         dst_hold(&rt->dst);
1495
1496         read_unlock_bh(&table->tb6_lock);
1497
1498         trace_fib6_table_lookup(net, rt, table->tb6_id, fl6);
1499         return rt;
1500 };
1501
1502 static struct dst_entry *ip6_route_redirect(struct net *net,
1503                                         const struct flowi6 *fl6,
1504                                         const struct in6_addr *gateway)
1505 {
1506         int flags = RT6_LOOKUP_F_HAS_SADDR;
1507         struct ip6rd_flowi rdfl;
1508
1509         rdfl.fl6 = *fl6;
1510         rdfl.gateway = *gateway;
1511
1512         return fib6_rule_lookup(net, &rdfl.fl6,
1513                                 flags, __ip6_route_redirect);
1514 }
1515
1516 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1517 {
1518         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1519         struct dst_entry *dst;
1520         struct flowi6 fl6;
1521
1522         memset(&fl6, 0, sizeof(fl6));
1523         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1524         fl6.flowi6_oif = oif;
1525         fl6.flowi6_mark = mark;
1526         fl6.daddr = iph->daddr;
1527         fl6.saddr = iph->saddr;
1528         fl6.flowlabel = ip6_flowinfo(iph);
1529
1530         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1531         rt6_do_redirect(dst, NULL, skb);
1532         dst_release(dst);
1533 }
1534 EXPORT_SYMBOL_GPL(ip6_redirect);
1535
1536 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1537                             u32 mark)
1538 {
1539         const struct ipv6hdr *iph = ipv6_hdr(skb);
1540         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1541         struct dst_entry *dst;
1542         struct flowi6 fl6;
1543
1544         memset(&fl6, 0, sizeof(fl6));
1545         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1546         fl6.flowi6_oif = oif;
1547         fl6.flowi6_mark = mark;
1548         fl6.daddr = msg->dest;
1549         fl6.saddr = iph->daddr;
1550
1551         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1552         rt6_do_redirect(dst, NULL, skb);
1553         dst_release(dst);
1554 }
1555
1556 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1557 {
1558         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1559 }
1560 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1561
1562 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1563 {
1564         struct net_device *dev = dst->dev;
1565         unsigned int mtu = dst_mtu(dst);
1566         struct net *net = dev_net(dev);
1567
1568         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1569
1570         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1571                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1572
1573         /*
1574          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1575          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1576          * IPV6_MAXPLEN is also valid and means: "any MSS,
1577          * rely only on pmtu discovery"
1578          */
1579         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1580                 mtu = IPV6_MAXPLEN;
1581         return mtu;
1582 }
1583
1584 static unsigned int ip6_mtu(const struct dst_entry *dst)
1585 {
1586         const struct rt6_info *rt = (const struct rt6_info *)dst;
1587         unsigned int mtu = rt->rt6i_pmtu;
1588         struct inet6_dev *idev;
1589
1590         if (mtu)
1591                 goto out;
1592
1593         mtu = dst_metric_raw(dst, RTAX_MTU);
1594         if (mtu)
1595                 goto out;
1596
1597         mtu = IPV6_MIN_MTU;
1598
1599         rcu_read_lock();
1600         idev = __in6_dev_get(dst->dev);
1601         if (idev)
1602                 mtu = idev->cnf.mtu6;
1603         rcu_read_unlock();
1604
1605 out:
1606         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1607 }
1608
1609 static struct dst_entry *icmp6_dst_gc_list;
1610 static DEFINE_SPINLOCK(icmp6_dst_lock);
1611
1612 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1613                                   struct flowi6 *fl6)
1614 {
1615         struct dst_entry *dst;
1616         struct rt6_info *rt;
1617         struct inet6_dev *idev = in6_dev_get(dev);
1618         struct net *net = dev_net(dev);
1619
1620         if (unlikely(!idev))
1621                 return ERR_PTR(-ENODEV);
1622
1623         rt = ip6_dst_alloc(net, dev, 0);
1624         if (unlikely(!rt)) {
1625                 in6_dev_put(idev);
1626                 dst = ERR_PTR(-ENOMEM);
1627                 goto out;
1628         }
1629
1630         rt->dst.flags |= DST_HOST;
1631         rt->dst.output  = ip6_output;
1632         atomic_set(&rt->dst.__refcnt, 1);
1633         rt->rt6i_gateway  = fl6->daddr;
1634         rt->rt6i_dst.addr = fl6->daddr;
1635         rt->rt6i_dst.plen = 128;
1636         rt->rt6i_idev     = idev;
1637         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1638
1639         spin_lock_bh(&icmp6_dst_lock);
1640         rt->dst.next = icmp6_dst_gc_list;
1641         icmp6_dst_gc_list = &rt->dst;
1642         spin_unlock_bh(&icmp6_dst_lock);
1643
1644         fib6_force_start_gc(net);
1645
1646         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1647
1648 out:
1649         return dst;
1650 }
1651
1652 int icmp6_dst_gc(void)
1653 {
1654         struct dst_entry *dst, **pprev;
1655         int more = 0;
1656
1657         spin_lock_bh(&icmp6_dst_lock);
1658         pprev = &icmp6_dst_gc_list;
1659
1660         while ((dst = *pprev) != NULL) {
1661                 if (!atomic_read(&dst->__refcnt)) {
1662                         *pprev = dst->next;
1663                         dst_free(dst);
1664                 } else {
1665                         pprev = &dst->next;
1666                         ++more;
1667                 }
1668         }
1669
1670         spin_unlock_bh(&icmp6_dst_lock);
1671
1672         return more;
1673 }
1674
1675 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1676                             void *arg)
1677 {
1678         struct dst_entry *dst, **pprev;
1679
1680         spin_lock_bh(&icmp6_dst_lock);
1681         pprev = &icmp6_dst_gc_list;
1682         while ((dst = *pprev) != NULL) {
1683                 struct rt6_info *rt = (struct rt6_info *) dst;
1684                 if (func(rt, arg)) {
1685                         *pprev = dst->next;
1686                         dst_free(dst);
1687                 } else {
1688                         pprev = &dst->next;
1689                 }
1690         }
1691         spin_unlock_bh(&icmp6_dst_lock);
1692 }
1693
1694 static int ip6_dst_gc(struct dst_ops *ops)
1695 {
1696         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1697         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1698         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1699         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1700         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1701         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1702         int entries;
1703
1704         entries = dst_entries_get_fast(ops);
1705         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1706             entries <= rt_max_size)
1707                 goto out;
1708
1709         net->ipv6.ip6_rt_gc_expire++;
1710         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1711         entries = dst_entries_get_slow(ops);
1712         if (entries < ops->gc_thresh)
1713                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1714 out:
1715         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1716         return entries > rt_max_size;
1717 }
1718
1719 static int ip6_convert_metrics(struct mx6_config *mxc,
1720                                const struct fib6_config *cfg)
1721 {
1722         bool ecn_ca = false;
1723         struct nlattr *nla;
1724         int remaining;
1725         u32 *mp;
1726
1727         if (!cfg->fc_mx)
1728                 return 0;
1729
1730         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1731         if (unlikely(!mp))
1732                 return -ENOMEM;
1733
1734         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1735                 int type = nla_type(nla);
1736                 u32 val;
1737
1738                 if (!type)
1739                         continue;
1740                 if (unlikely(type > RTAX_MAX))
1741                         goto err;
1742
1743                 if (type == RTAX_CC_ALGO) {
1744                         char tmp[TCP_CA_NAME_MAX];
1745
1746                         nla_strlcpy(tmp, nla, sizeof(tmp));
1747                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1748                         if (val == TCP_CA_UNSPEC)
1749                                 goto err;
1750                 } else {
1751                         val = nla_get_u32(nla);
1752                 }
1753                 if (type == RTAX_HOPLIMIT && val > 255)
1754                         val = 255;
1755                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1756                         goto err;
1757
1758                 mp[type - 1] = val;
1759                 __set_bit(type - 1, mxc->mx_valid);
1760         }
1761
1762         if (ecn_ca) {
1763                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1764                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1765         }
1766
1767         mxc->mx = mp;
1768         return 0;
1769  err:
1770         kfree(mp);
1771         return -EINVAL;
1772 }
1773
1774 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1775 {
1776         struct net *net = cfg->fc_nlinfo.nl_net;
1777         struct rt6_info *rt = NULL;
1778         struct net_device *dev = NULL;
1779         struct inet6_dev *idev = NULL;
1780         struct fib6_table *table;
1781         int addr_type;
1782         int err = -EINVAL;
1783
1784         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1785                 goto out;
1786 #ifndef CONFIG_IPV6_SUBTREES
1787         if (cfg->fc_src_len)
1788                 goto out;
1789 #endif
1790         if (cfg->fc_ifindex) {
1791                 err = -ENODEV;
1792                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1793                 if (!dev)
1794                         goto out;
1795                 idev = in6_dev_get(dev);
1796                 if (!idev)
1797                         goto out;
1798         }
1799
1800         if (cfg->fc_metric == 0)
1801                 cfg->fc_metric = IP6_RT_PRIO_USER;
1802
1803         err = -ENOBUFS;
1804         if (cfg->fc_nlinfo.nlh &&
1805             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1806                 table = fib6_get_table(net, cfg->fc_table);
1807                 if (!table) {
1808                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1809                         table = fib6_new_table(net, cfg->fc_table);
1810                 }
1811         } else {
1812                 table = fib6_new_table(net, cfg->fc_table);
1813         }
1814
1815         if (!table)
1816                 goto out;
1817
1818         rt = ip6_dst_alloc(net, NULL,
1819                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1820
1821         if (!rt) {
1822                 err = -ENOMEM;
1823                 goto out;
1824         }
1825
1826         if (cfg->fc_flags & RTF_EXPIRES)
1827                 rt6_set_expires(rt, jiffies +
1828                                 clock_t_to_jiffies(cfg->fc_expires));
1829         else
1830                 rt6_clean_expires(rt);
1831
1832         if (cfg->fc_protocol == RTPROT_UNSPEC)
1833                 cfg->fc_protocol = RTPROT_BOOT;
1834         rt->rt6i_protocol = cfg->fc_protocol;
1835
1836         addr_type = ipv6_addr_type(&cfg->fc_dst);
1837
1838         if (addr_type & IPV6_ADDR_MULTICAST)
1839                 rt->dst.input = ip6_mc_input;
1840         else if (cfg->fc_flags & RTF_LOCAL)
1841                 rt->dst.input = ip6_input;
1842         else
1843                 rt->dst.input = ip6_forward;
1844
1845         rt->dst.output = ip6_output;
1846
1847         if (cfg->fc_encap) {
1848                 struct lwtunnel_state *lwtstate;
1849
1850                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1851                                            cfg->fc_encap, AF_INET6, cfg,
1852                                            &lwtstate);
1853                 if (err)
1854                         goto out;
1855                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1856                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1857                         rt->dst.lwtstate->orig_output = rt->dst.output;
1858                         rt->dst.output = lwtunnel_output;
1859                 }
1860                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1861                         rt->dst.lwtstate->orig_input = rt->dst.input;
1862                         rt->dst.input = lwtunnel_input;
1863                 }
1864         }
1865
1866         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1867         rt->rt6i_dst.plen = cfg->fc_dst_len;
1868         if (rt->rt6i_dst.plen == 128)
1869                 rt->dst.flags |= DST_HOST;
1870
1871 #ifdef CONFIG_IPV6_SUBTREES
1872         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1873         rt->rt6i_src.plen = cfg->fc_src_len;
1874 #endif
1875
1876         rt->rt6i_metric = cfg->fc_metric;
1877
1878         /* We cannot add true routes via loopback here,
1879            they would result in kernel looping; promote them to reject routes
1880          */
1881         if ((cfg->fc_flags & RTF_REJECT) ||
1882             (dev && (dev->flags & IFF_LOOPBACK) &&
1883              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1884              !(cfg->fc_flags & RTF_LOCAL))) {
1885                 /* hold loopback dev/idev if we haven't done so. */
1886                 if (dev != net->loopback_dev) {
1887                         if (dev) {
1888                                 dev_put(dev);
1889                                 in6_dev_put(idev);
1890                         }
1891                         dev = net->loopback_dev;
1892                         dev_hold(dev);
1893                         idev = in6_dev_get(dev);
1894                         if (!idev) {
1895                                 err = -ENODEV;
1896                                 goto out;
1897                         }
1898                 }
1899                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1900                 switch (cfg->fc_type) {
1901                 case RTN_BLACKHOLE:
1902                         rt->dst.error = -EINVAL;
1903                         rt->dst.output = dst_discard_out;
1904                         rt->dst.input = dst_discard;
1905                         break;
1906                 case RTN_PROHIBIT:
1907                         rt->dst.error = -EACCES;
1908                         rt->dst.output = ip6_pkt_prohibit_out;
1909                         rt->dst.input = ip6_pkt_prohibit;
1910                         break;
1911                 case RTN_THROW:
1912                 case RTN_UNREACHABLE:
1913                 default:
1914                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1915                                         : (cfg->fc_type == RTN_UNREACHABLE)
1916                                         ? -EHOSTUNREACH : -ENETUNREACH;
1917                         rt->dst.output = ip6_pkt_discard_out;
1918                         rt->dst.input = ip6_pkt_discard;
1919                         break;
1920                 }
1921                 goto install_route;
1922         }
1923
1924         if (cfg->fc_flags & RTF_GATEWAY) {
1925                 const struct in6_addr *gw_addr;
1926                 int gwa_type;
1927
1928                 gw_addr = &cfg->fc_gateway;
1929                 gwa_type = ipv6_addr_type(gw_addr);
1930
1931                 /* if gw_addr is local we will fail to detect this in case
1932                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1933                  * will return already-added prefix route via interface that
1934                  * prefix route was assigned to, which might be non-loopback.
1935                  */
1936                 err = -EINVAL;
1937                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1938                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1939                                             dev : NULL, 0, 0))
1940                         goto out;
1941
1942                 rt->rt6i_gateway = *gw_addr;
1943
1944                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1945                         struct rt6_info *grt;
1946
1947                         /* IPv6 strictly inhibits using not link-local
1948                            addresses as nexthop address.
1949                            Otherwise, router will not able to send redirects.
1950                            It is very good, but in some (rare!) circumstances
1951                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1952                            some exceptions. --ANK
1953                          */
1954                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1955                                 goto out;
1956
1957                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1958
1959                         err = -EHOSTUNREACH;
1960                         if (!grt)
1961                                 goto out;
1962                         if (dev) {
1963                                 if (dev != grt->dst.dev) {
1964                                         ip6_rt_put(grt);
1965                                         goto out;
1966                                 }
1967                         } else {
1968                                 dev = grt->dst.dev;
1969                                 idev = grt->rt6i_idev;
1970                                 dev_hold(dev);
1971                                 in6_dev_hold(grt->rt6i_idev);
1972                         }
1973                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1974                                 err = 0;
1975                         ip6_rt_put(grt);
1976
1977                         if (err)
1978                                 goto out;
1979                 }
1980                 err = -EINVAL;
1981                 if (!dev || (dev->flags & IFF_LOOPBACK))
1982                         goto out;
1983         }
1984
1985         err = -ENODEV;
1986         if (!dev)
1987                 goto out;
1988
1989         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1990                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1991                         err = -EINVAL;
1992                         goto out;
1993                 }
1994                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1995                 rt->rt6i_prefsrc.plen = 128;
1996         } else
1997                 rt->rt6i_prefsrc.plen = 0;
1998
1999         rt->rt6i_flags = cfg->fc_flags;
2000
2001 install_route:
2002         rt->dst.dev = dev;
2003         rt->rt6i_idev = idev;
2004         rt->rt6i_table = table;
2005
2006         cfg->fc_nlinfo.nl_net = dev_net(dev);
2007
2008         return rt;
2009 out:
2010         if (dev)
2011                 dev_put(dev);
2012         if (idev)
2013                 in6_dev_put(idev);
2014         if (rt)
2015                 dst_free(&rt->dst);
2016
2017         return ERR_PTR(err);
2018 }
2019
2020 int ip6_route_add(struct fib6_config *cfg)
2021 {
2022         struct mx6_config mxc = { .mx = NULL, };
2023         struct rt6_info *rt;
2024         int err;
2025
2026         rt = ip6_route_info_create(cfg);
2027         if (IS_ERR(rt)) {
2028                 err = PTR_ERR(rt);
2029                 rt = NULL;
2030                 goto out;
2031         }
2032
2033         err = ip6_convert_metrics(&mxc, cfg);
2034         if (err)
2035                 goto out;
2036
2037         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2038
2039         kfree(mxc.mx);
2040
2041         return err;
2042 out:
2043         if (rt)
2044                 dst_free(&rt->dst);
2045
2046         return err;
2047 }
2048
2049 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2050 {
2051         int err;
2052         struct fib6_table *table;
2053         struct net *net = dev_net(rt->dst.dev);
2054
2055         if (rt == net->ipv6.ip6_null_entry ||
2056             rt->dst.flags & DST_NOCACHE) {
2057                 err = -ENOENT;
2058                 goto out;
2059         }
2060
2061         table = rt->rt6i_table;
2062         write_lock_bh(&table->tb6_lock);
2063         err = fib6_del(rt, info);
2064         write_unlock_bh(&table->tb6_lock);
2065
2066 out:
2067         ip6_rt_put(rt);
2068         return err;
2069 }
2070
2071 int ip6_del_rt(struct rt6_info *rt)
2072 {
2073         struct nl_info info = {
2074                 .nl_net = dev_net(rt->dst.dev),
2075         };
2076         return __ip6_del_rt(rt, &info);
2077 }
2078
2079 static int ip6_route_del(struct fib6_config *cfg)
2080 {
2081         struct fib6_table *table;
2082         struct fib6_node *fn;
2083         struct rt6_info *rt;
2084         int err = -ESRCH;
2085
2086         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2087         if (!table)
2088                 return err;
2089
2090         read_lock_bh(&table->tb6_lock);
2091
2092         fn = fib6_locate(&table->tb6_root,
2093                          &cfg->fc_dst, cfg->fc_dst_len,
2094                          &cfg->fc_src, cfg->fc_src_len);
2095
2096         if (fn) {
2097                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2098                         if ((rt->rt6i_flags & RTF_CACHE) &&
2099                             !(cfg->fc_flags & RTF_CACHE))
2100                                 continue;
2101                         if (cfg->fc_ifindex &&
2102                             (!rt->dst.dev ||
2103                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2104                                 continue;
2105                         if (cfg->fc_flags & RTF_GATEWAY &&
2106                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2107                                 continue;
2108                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2109                                 continue;
2110                         dst_hold(&rt->dst);
2111                         read_unlock_bh(&table->tb6_lock);
2112
2113                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2114                 }
2115         }
2116         read_unlock_bh(&table->tb6_lock);
2117
2118         return err;
2119 }
2120
2121 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2122 {
2123         struct netevent_redirect netevent;
2124         struct rt6_info *rt, *nrt = NULL;
2125         struct ndisc_options ndopts;
2126         struct inet6_dev *in6_dev;
2127         struct neighbour *neigh;
2128         struct rd_msg *msg;
2129         int optlen, on_link;
2130         u8 *lladdr;
2131
2132         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2133         optlen -= sizeof(*msg);
2134
2135         if (optlen < 0) {
2136                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2137                 return;
2138         }
2139
2140         msg = (struct rd_msg *)icmp6_hdr(skb);
2141
2142         if (ipv6_addr_is_multicast(&msg->dest)) {
2143                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2144                 return;
2145         }
2146
2147         on_link = 0;
2148         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2149                 on_link = 1;
2150         } else if (ipv6_addr_type(&msg->target) !=
2151                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2152                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2153                 return;
2154         }
2155
2156         in6_dev = __in6_dev_get(skb->dev);
2157         if (!in6_dev)
2158                 return;
2159         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2160                 return;
2161
2162         /* RFC2461 8.1:
2163          *      The IP source address of the Redirect MUST be the same as the current
2164          *      first-hop router for the specified ICMP Destination Address.
2165          */
2166
2167         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2168                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2169                 return;
2170         }
2171
2172         lladdr = NULL;
2173         if (ndopts.nd_opts_tgt_lladdr) {
2174                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2175                                              skb->dev);
2176                 if (!lladdr) {
2177                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2178                         return;
2179                 }
2180         }
2181
2182         rt = (struct rt6_info *) dst;
2183         if (rt->rt6i_flags & RTF_REJECT) {
2184                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2185                 return;
2186         }
2187
2188         /* Redirect received -> path was valid.
2189          * Look, redirects are sent only in response to data packets,
2190          * so that this nexthop apparently is reachable. --ANK
2191          */
2192         dst_confirm(&rt->dst);
2193
2194         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2195         if (!neigh)
2196                 return;
2197
2198         /*
2199          *      We have finally decided to accept it.
2200          */
2201
2202         neigh_update(neigh, lladdr, NUD_STALE,
2203                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2204                      NEIGH_UPDATE_F_OVERRIDE|
2205                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2206                                      NEIGH_UPDATE_F_ISROUTER))
2207                      );
2208
2209         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2210         if (!nrt)
2211                 goto out;
2212
2213         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2214         if (on_link)
2215                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2216
2217         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2218
2219         if (ip6_ins_rt(nrt))
2220                 goto out;
2221
2222         netevent.old = &rt->dst;
2223         netevent.new = &nrt->dst;
2224         netevent.daddr = &msg->dest;
2225         netevent.neigh = neigh;
2226         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2227
2228         if (rt->rt6i_flags & RTF_CACHE) {
2229                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2230                 ip6_del_rt(rt);
2231         }
2232
2233 out:
2234         neigh_release(neigh);
2235 }
2236
2237 /*
2238  *      Misc support functions
2239  */
2240
2241 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2242 {
2243         BUG_ON(from->dst.from);
2244
2245         rt->rt6i_flags &= ~RTF_EXPIRES;
2246         dst_hold(&from->dst);
2247         rt->dst.from = &from->dst;
2248         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2249 }
2250
2251 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2252 {
2253         rt->dst.input = ort->dst.input;
2254         rt->dst.output = ort->dst.output;
2255         rt->rt6i_dst = ort->rt6i_dst;
2256         rt->dst.error = ort->dst.error;
2257         rt->rt6i_idev = ort->rt6i_idev;
2258         if (rt->rt6i_idev)
2259                 in6_dev_hold(rt->rt6i_idev);
2260         rt->dst.lastuse = jiffies;
2261         rt->rt6i_gateway = ort->rt6i_gateway;
2262         rt->rt6i_flags = ort->rt6i_flags;
2263         rt6_set_from(rt, ort);
2264         rt->rt6i_metric = ort->rt6i_metric;
2265 #ifdef CONFIG_IPV6_SUBTREES
2266         rt->rt6i_src = ort->rt6i_src;
2267 #endif
2268         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2269         rt->rt6i_table = ort->rt6i_table;
2270         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2271 }
2272
2273 #ifdef CONFIG_IPV6_ROUTE_INFO
2274 static struct rt6_info *rt6_get_route_info(struct net *net,
2275                                            const struct in6_addr *prefix, int prefixlen,
2276                                            const struct in6_addr *gwaddr, int ifindex)
2277 {
2278         struct fib6_node *fn;
2279         struct rt6_info *rt = NULL;
2280         struct fib6_table *table;
2281
2282         table = fib6_get_table(net, RT6_TABLE_INFO);
2283         if (!table)
2284                 return NULL;
2285
2286         read_lock_bh(&table->tb6_lock);
2287         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2288         if (!fn)
2289                 goto out;
2290
2291         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2292                 if (rt->dst.dev->ifindex != ifindex)
2293                         continue;
2294                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2295                         continue;
2296                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2297                         continue;
2298                 dst_hold(&rt->dst);
2299                 break;
2300         }
2301 out:
2302         read_unlock_bh(&table->tb6_lock);
2303         return rt;
2304 }
2305
2306 static struct rt6_info *rt6_add_route_info(struct net *net,
2307                                            const struct in6_addr *prefix, int prefixlen,
2308                                            const struct in6_addr *gwaddr, int ifindex,
2309                                            unsigned int pref)
2310 {
2311         struct fib6_config cfg = {
2312                 .fc_metric      = IP6_RT_PRIO_USER,
2313                 .fc_ifindex     = ifindex,
2314                 .fc_dst_len     = prefixlen,
2315                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2316                                   RTF_UP | RTF_PREF(pref),
2317                 .fc_nlinfo.portid = 0,
2318                 .fc_nlinfo.nlh = NULL,
2319                 .fc_nlinfo.nl_net = net,
2320         };
2321
2322         cfg.fc_table = l3mdev_fib_table_by_index(net, ifindex) ? : RT6_TABLE_INFO;
2323         cfg.fc_dst = *prefix;
2324         cfg.fc_gateway = *gwaddr;
2325
2326         /* We should treat it as a default route if prefix length is 0. */
2327         if (!prefixlen)
2328                 cfg.fc_flags |= RTF_DEFAULT;
2329
2330         ip6_route_add(&cfg);
2331
2332         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2333 }
2334 #endif
2335
2336 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2337 {
2338         struct rt6_info *rt;
2339         struct fib6_table *table;
2340
2341         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2342         if (!table)
2343                 return NULL;
2344
2345         read_lock_bh(&table->tb6_lock);
2346         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2347                 if (dev == rt->dst.dev &&
2348                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2349                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2350                         break;
2351         }
2352         if (rt)
2353                 dst_hold(&rt->dst);
2354         read_unlock_bh(&table->tb6_lock);
2355         return rt;
2356 }
2357
2358 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2359                                      struct net_device *dev,
2360                                      unsigned int pref)
2361 {
2362         struct fib6_config cfg = {
2363                 .fc_table       = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
2364                 .fc_metric      = IP6_RT_PRIO_USER,
2365                 .fc_ifindex     = dev->ifindex,
2366                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2367                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2368                 .fc_nlinfo.portid = 0,
2369                 .fc_nlinfo.nlh = NULL,
2370                 .fc_nlinfo.nl_net = dev_net(dev),
2371         };
2372
2373         cfg.fc_gateway = *gwaddr;
2374
2375         ip6_route_add(&cfg);
2376
2377         return rt6_get_dflt_router(gwaddr, dev);
2378 }
2379
2380 void rt6_purge_dflt_routers(struct net *net)
2381 {
2382         struct rt6_info *rt;
2383         struct fib6_table *table;
2384
2385         /* NOTE: Keep consistent with rt6_get_dflt_router */
2386         table = fib6_get_table(net, RT6_TABLE_DFLT);
2387         if (!table)
2388                 return;
2389
2390 restart:
2391         read_lock_bh(&table->tb6_lock);
2392         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2393                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2394                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2395                         dst_hold(&rt->dst);
2396                         read_unlock_bh(&table->tb6_lock);
2397                         ip6_del_rt(rt);
2398                         goto restart;
2399                 }
2400         }
2401         read_unlock_bh(&table->tb6_lock);
2402 }
2403
2404 static void rtmsg_to_fib6_config(struct net *net,
2405                                  struct in6_rtmsg *rtmsg,
2406                                  struct fib6_config *cfg)
2407 {
2408         memset(cfg, 0, sizeof(*cfg));
2409
2410         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2411                          : RT6_TABLE_MAIN;
2412         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2413         cfg->fc_metric = rtmsg->rtmsg_metric;
2414         cfg->fc_expires = rtmsg->rtmsg_info;
2415         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2416         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2417         cfg->fc_flags = rtmsg->rtmsg_flags;
2418
2419         cfg->fc_nlinfo.nl_net = net;
2420
2421         cfg->fc_dst = rtmsg->rtmsg_dst;
2422         cfg->fc_src = rtmsg->rtmsg_src;
2423         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2424 }
2425
2426 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2427 {
2428         struct fib6_config cfg;
2429         struct in6_rtmsg rtmsg;
2430         int err;
2431
2432         switch (cmd) {
2433         case SIOCADDRT:         /* Add a route */
2434         case SIOCDELRT:         /* Delete a route */
2435                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2436                         return -EPERM;
2437                 err = copy_from_user(&rtmsg, arg,
2438                                      sizeof(struct in6_rtmsg));
2439                 if (err)
2440                         return -EFAULT;
2441
2442                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2443
2444                 rtnl_lock();
2445                 switch (cmd) {
2446                 case SIOCADDRT:
2447                         err = ip6_route_add(&cfg);
2448                         break;
2449                 case SIOCDELRT:
2450                         err = ip6_route_del(&cfg);
2451                         break;
2452                 default:
2453                         err = -EINVAL;
2454                 }
2455                 rtnl_unlock();
2456
2457                 return err;
2458         }
2459
2460         return -EINVAL;
2461 }
2462
2463 /*
2464  *      Drop the packet on the floor
2465  */
2466
2467 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2468 {
2469         int type;
2470         struct dst_entry *dst = skb_dst(skb);
2471         switch (ipstats_mib_noroutes) {
2472         case IPSTATS_MIB_INNOROUTES:
2473                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2474                 if (type == IPV6_ADDR_ANY) {
2475                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2476                                       IPSTATS_MIB_INADDRERRORS);
2477                         break;
2478                 }
2479                 /* FALLTHROUGH */
2480         case IPSTATS_MIB_OUTNOROUTES:
2481                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2482                               ipstats_mib_noroutes);
2483                 break;
2484         }
2485         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2486         kfree_skb(skb);
2487         return 0;
2488 }
2489
2490 static int ip6_pkt_discard(struct sk_buff *skb)
2491 {
2492         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2493 }
2494
2495 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2496 {
2497         skb->dev = skb_dst(skb)->dev;
2498         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2499 }
2500
2501 static int ip6_pkt_prohibit(struct sk_buff *skb)
2502 {
2503         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2504 }
2505
2506 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2507 {
2508         skb->dev = skb_dst(skb)->dev;
2509         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2510 }
2511
2512 /*
2513  *      Allocate a dst for local (unicast / anycast) address.
2514  */
2515
2516 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2517                                     const struct in6_addr *addr,
2518                                     bool anycast)
2519 {
2520         u32 tb_id;
2521         struct net *net = dev_net(idev->dev);
2522         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2523                                             DST_NOCOUNT);
2524         if (!rt)
2525                 return ERR_PTR(-ENOMEM);
2526
2527         in6_dev_hold(idev);
2528
2529         rt->dst.flags |= DST_HOST;
2530         rt->dst.input = ip6_input;
2531         rt->dst.output = ip6_output;
2532         rt->rt6i_idev = idev;
2533
2534         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2535         if (anycast)
2536                 rt->rt6i_flags |= RTF_ANYCAST;
2537         else
2538                 rt->rt6i_flags |= RTF_LOCAL;
2539
2540         rt->rt6i_gateway  = *addr;
2541         rt->rt6i_dst.addr = *addr;
2542         rt->rt6i_dst.plen = 128;
2543         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2544         rt->rt6i_table = fib6_get_table(net, tb_id);
2545         rt->dst.flags |= DST_NOCACHE;
2546
2547         atomic_set(&rt->dst.__refcnt, 1);
2548
2549         return rt;
2550 }
2551
2552 int ip6_route_get_saddr(struct net *net,
2553                         struct rt6_info *rt,
2554                         const struct in6_addr *daddr,
2555                         unsigned int prefs,
2556                         struct in6_addr *saddr)
2557 {
2558         struct inet6_dev *idev =
2559                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2560         int err = 0;
2561         if (rt && rt->rt6i_prefsrc.plen)
2562                 *saddr = rt->rt6i_prefsrc.addr;
2563         else
2564                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2565                                          daddr, prefs, saddr);
2566         return err;
2567 }
2568
2569 /* remove deleted ip from prefsrc entries */
2570 struct arg_dev_net_ip {
2571         struct net_device *dev;
2572         struct net *net;
2573         struct in6_addr *addr;
2574 };
2575
2576 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2577 {
2578         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2579         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2580         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2581
2582         if (((void *)rt->dst.dev == dev || !dev) &&
2583             rt != net->ipv6.ip6_null_entry &&
2584             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2585                 /* remove prefsrc entry */
2586                 rt->rt6i_prefsrc.plen = 0;
2587         }
2588         return 0;
2589 }
2590
2591 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2592 {
2593         struct net *net = dev_net(ifp->idev->dev);
2594         struct arg_dev_net_ip adni = {
2595                 .dev = ifp->idev->dev,
2596                 .net = net,
2597                 .addr = &ifp->addr,
2598         };
2599         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2600 }
2601
2602 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2603 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2604
2605 /* Remove routers and update dst entries when gateway turn into host. */
2606 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2607 {
2608         struct in6_addr *gateway = (struct in6_addr *)arg;
2609
2610         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2611              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2612              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2613                 return -1;
2614         }
2615         return 0;
2616 }
2617
2618 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2619 {
2620         fib6_clean_all(net, fib6_clean_tohost, gateway);
2621 }
2622
2623 struct arg_dev_net {
2624         struct net_device *dev;
2625         struct net *net;
2626 };
2627
2628 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2629 {
2630         const struct arg_dev_net *adn = arg;
2631         const struct net_device *dev = adn->dev;
2632
2633         if ((rt->dst.dev == dev || !dev) &&
2634             rt != adn->net->ipv6.ip6_null_entry)
2635                 return -1;
2636
2637         return 0;
2638 }
2639
2640 void rt6_ifdown(struct net *net, struct net_device *dev)
2641 {
2642         struct arg_dev_net adn = {
2643                 .dev = dev,
2644                 .net = net,
2645         };
2646
2647         fib6_clean_all(net, fib6_ifdown, &adn);
2648         icmp6_clean_all(fib6_ifdown, &adn);
2649         if (dev)
2650                 rt6_uncached_list_flush_dev(net, dev);
2651 }
2652
2653 struct rt6_mtu_change_arg {
2654         struct net_device *dev;
2655         unsigned int mtu;
2656 };
2657
2658 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2659 {
2660         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2661         struct inet6_dev *idev;
2662
2663         /* In IPv6 pmtu discovery is not optional,
2664            so that RTAX_MTU lock cannot disable it.
2665            We still use this lock to block changes
2666            caused by addrconf/ndisc.
2667         */
2668
2669         idev = __in6_dev_get(arg->dev);
2670         if (!idev)
2671                 return 0;
2672
2673         /* For administrative MTU increase, there is no way to discover
2674            IPv6 PMTU increase, so PMTU increase should be updated here.
2675            Since RFC 1981 doesn't include administrative MTU increase
2676            update PMTU increase is a MUST. (i.e. jumbo frame)
2677          */
2678         /*
2679            If new MTU is less than route PMTU, this new MTU will be the
2680            lowest MTU in the path, update the route PMTU to reflect PMTU
2681            decreases; if new MTU is greater than route PMTU, and the
2682            old MTU is the lowest MTU in the path, update the route PMTU
2683            to reflect the increase. In this case if the other nodes' MTU
2684            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2685            PMTU discouvery.
2686          */
2687         if (rt->dst.dev == arg->dev &&
2688             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2689                 if (rt->rt6i_flags & RTF_CACHE) {
2690                         /* For RTF_CACHE with rt6i_pmtu == 0
2691                          * (i.e. a redirected route),
2692                          * the metrics of its rt->dst.from has already
2693                          * been updated.
2694                          */
2695                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2696                                 rt->rt6i_pmtu = arg->mtu;
2697                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2698                            (dst_mtu(&rt->dst) < arg->mtu &&
2699                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2700                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2701                 }
2702         }
2703         return 0;
2704 }
2705
2706 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2707 {
2708         struct rt6_mtu_change_arg arg = {
2709                 .dev = dev,
2710                 .mtu = mtu,
2711         };
2712
2713         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2714 }
2715
2716 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2717         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2718         [RTA_OIF]               = { .type = NLA_U32 },
2719         [RTA_IIF]               = { .type = NLA_U32 },
2720         [RTA_PRIORITY]          = { .type = NLA_U32 },
2721         [RTA_METRICS]           = { .type = NLA_NESTED },
2722         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2723         [RTA_PREF]              = { .type = NLA_U8 },
2724         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2725         [RTA_ENCAP]             = { .type = NLA_NESTED },
2726         [RTA_EXPIRES]           = { .type = NLA_U32 },
2727 };
2728
2729 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2730                               struct fib6_config *cfg)
2731 {
2732         struct rtmsg *rtm;
2733         struct nlattr *tb[RTA_MAX+1];
2734         unsigned int pref;
2735         int err;
2736
2737         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2738         if (err < 0)
2739                 goto errout;
2740
2741         err = -EINVAL;
2742         rtm = nlmsg_data(nlh);
2743         memset(cfg, 0, sizeof(*cfg));
2744
2745         cfg->fc_table = rtm->rtm_table;
2746         cfg->fc_dst_len = rtm->rtm_dst_len;
2747         cfg->fc_src_len = rtm->rtm_src_len;
2748         cfg->fc_flags = RTF_UP;
2749         cfg->fc_protocol = rtm->rtm_protocol;
2750         cfg->fc_type = rtm->rtm_type;
2751
2752         if (rtm->rtm_type == RTN_UNREACHABLE ||
2753             rtm->rtm_type == RTN_BLACKHOLE ||
2754             rtm->rtm_type == RTN_PROHIBIT ||
2755             rtm->rtm_type == RTN_THROW)
2756                 cfg->fc_flags |= RTF_REJECT;
2757
2758         if (rtm->rtm_type == RTN_LOCAL)
2759                 cfg->fc_flags |= RTF_LOCAL;
2760
2761         if (rtm->rtm_flags & RTM_F_CLONED)
2762                 cfg->fc_flags |= RTF_CACHE;
2763
2764         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2765         cfg->fc_nlinfo.nlh = nlh;
2766         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2767
2768         if (tb[RTA_GATEWAY]) {
2769                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2770                 cfg->fc_flags |= RTF_GATEWAY;
2771         }
2772
2773         if (tb[RTA_DST]) {
2774                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2775
2776                 if (nla_len(tb[RTA_DST]) < plen)
2777                         goto errout;
2778
2779                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2780         }
2781
2782         if (tb[RTA_SRC]) {
2783                 int plen = (rtm->rtm_src_len + 7) >> 3;
2784
2785                 if (nla_len(tb[RTA_SRC]) < plen)
2786                         goto errout;
2787
2788                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2789         }
2790
2791         if (tb[RTA_PREFSRC])
2792                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2793
2794         if (tb[RTA_OIF])
2795                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2796
2797         if (tb[RTA_PRIORITY])
2798                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2799
2800         if (tb[RTA_METRICS]) {
2801                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2802                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2803         }
2804
2805         if (tb[RTA_TABLE])
2806                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2807
2808         if (tb[RTA_MULTIPATH]) {
2809                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2810                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2811         }
2812
2813         if (tb[RTA_PREF]) {
2814                 pref = nla_get_u8(tb[RTA_PREF]);
2815                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2816                     pref != ICMPV6_ROUTER_PREF_HIGH)
2817                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2818                 cfg->fc_flags |= RTF_PREF(pref);
2819         }
2820
2821         if (tb[RTA_ENCAP])
2822                 cfg->fc_encap = tb[RTA_ENCAP];
2823
2824         if (tb[RTA_ENCAP_TYPE])
2825                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2826
2827         if (tb[RTA_EXPIRES]) {
2828                 unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
2829
2830                 if (addrconf_finite_timeout(timeout)) {
2831                         cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
2832                         cfg->fc_flags |= RTF_EXPIRES;
2833                 }
2834         }
2835
2836         err = 0;
2837 errout:
2838         return err;
2839 }
2840
2841 struct rt6_nh {
2842         struct rt6_info *rt6_info;
2843         struct fib6_config r_cfg;
2844         struct mx6_config mxc;
2845         struct list_head next;
2846 };
2847
2848 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2849 {
2850         struct rt6_nh *nh;
2851
2852         list_for_each_entry(nh, rt6_nh_list, next) {
2853                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2854                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2855                         nh->r_cfg.fc_ifindex);
2856         }
2857 }
2858
2859 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2860                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2861 {
2862         struct rt6_nh *nh;
2863         struct rt6_info *rtnh;
2864         int err = -EEXIST;
2865
2866         list_for_each_entry(nh, rt6_nh_list, next) {
2867                 /* check if rt6_info already exists */
2868                 rtnh = nh->rt6_info;
2869
2870                 if (rtnh->dst.dev == rt->dst.dev &&
2871                     rtnh->rt6i_idev == rt->rt6i_idev &&
2872                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2873                                     &rt->rt6i_gateway))
2874                         return err;
2875         }
2876
2877         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2878         if (!nh)
2879                 return -ENOMEM;
2880         nh->rt6_info = rt;
2881         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2882         if (err) {
2883                 kfree(nh);
2884                 return err;
2885         }
2886         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2887         list_add_tail(&nh->next, rt6_nh_list);
2888
2889         return 0;
2890 }
2891
2892 static int ip6_route_multipath_add(struct fib6_config *cfg)
2893 {
2894         struct fib6_config r_cfg;
2895         struct rtnexthop *rtnh;
2896         struct rt6_info *rt;
2897         struct rt6_nh *err_nh;
2898         struct rt6_nh *nh, *nh_safe;
2899         int remaining;
2900         int attrlen;
2901         int err = 1;
2902         int nhn = 0;
2903         int replace = (cfg->fc_nlinfo.nlh &&
2904                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2905         LIST_HEAD(rt6_nh_list);
2906
2907         remaining = cfg->fc_mp_len;
2908         rtnh = (struct rtnexthop *)cfg->fc_mp;
2909
2910         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2911          * rt6_info structs per nexthop
2912          */
2913         while (rtnh_ok(rtnh, remaining)) {
2914                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2915                 if (rtnh->rtnh_ifindex)
2916                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2917
2918                 attrlen = rtnh_attrlen(rtnh);
2919                 if (attrlen > 0) {
2920                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2921
2922                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2923                         if (nla) {
2924                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2925                                 r_cfg.fc_flags |= RTF_GATEWAY;
2926                         }
2927                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2928                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2929                         if (nla)
2930                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2931                 }
2932
2933                 rt = ip6_route_info_create(&r_cfg);
2934                 if (IS_ERR(rt)) {
2935                         err = PTR_ERR(rt);
2936                         rt = NULL;
2937                         goto cleanup;
2938                 }
2939
2940                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2941                 if (err) {
2942                         dst_free(&rt->dst);
2943                         goto cleanup;
2944                 }
2945
2946                 rtnh = rtnh_next(rtnh, &remaining);
2947         }
2948
2949         err_nh = NULL;
2950         list_for_each_entry(nh, &rt6_nh_list, next) {
2951                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2952                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2953                 nh->rt6_info = NULL;
2954                 if (err) {
2955                         if (replace && nhn)
2956                                 ip6_print_replace_route_err(&rt6_nh_list);
2957                         err_nh = nh;
2958                         goto add_errout;
2959                 }
2960
2961                 /* Because each route is added like a single route we remove
2962                  * these flags after the first nexthop: if there is a collision,
2963                  * we have already failed to add the first nexthop:
2964                  * fib6_add_rt2node() has rejected it; when replacing, old
2965                  * nexthops have been replaced by first new, the rest should
2966                  * be added to it.
2967                  */
2968                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2969                                                      NLM_F_REPLACE);
2970                 nhn++;
2971         }
2972
2973         goto cleanup;
2974
2975 add_errout:
2976         /* Delete routes that were already added */
2977         list_for_each_entry(nh, &rt6_nh_list, next) {
2978                 if (err_nh == nh)
2979                         break;
2980                 ip6_route_del(&nh->r_cfg);
2981         }
2982
2983 cleanup:
2984         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2985                 if (nh->rt6_info)
2986                         dst_free(&nh->rt6_info->dst);
2987                 kfree(nh->mxc.mx);
2988                 list_del(&nh->next);
2989                 kfree(nh);
2990         }
2991
2992         return err;
2993 }
2994
2995 static int ip6_route_multipath_del(struct fib6_config *cfg)
2996 {
2997         struct fib6_config r_cfg;
2998         struct rtnexthop *rtnh;
2999         int remaining;
3000         int attrlen;
3001         int err = 1, last_err = 0;
3002
3003         remaining = cfg->fc_mp_len;
3004         rtnh = (struct rtnexthop *)cfg->fc_mp;
3005
3006         /* Parse a Multipath Entry */
3007         while (rtnh_ok(rtnh, remaining)) {
3008                 memcpy(&r_cfg, cfg, sizeof(*cfg));
3009                 if (rtnh->rtnh_ifindex)
3010                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
3011
3012                 attrlen = rtnh_attrlen(rtnh);
3013                 if (attrlen > 0) {
3014                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
3015
3016                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
3017                         if (nla) {
3018                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
3019                                 r_cfg.fc_flags |= RTF_GATEWAY;
3020                         }
3021                 }
3022                 err = ip6_route_del(&r_cfg);
3023                 if (err)
3024                         last_err = err;
3025
3026                 rtnh = rtnh_next(rtnh, &remaining);
3027         }
3028
3029         return last_err;
3030 }
3031
3032 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3033 {
3034         struct fib6_config cfg;
3035         int err;
3036
3037         err = rtm_to_fib6_config(skb, nlh, &cfg);
3038         if (err < 0)
3039                 return err;
3040
3041         if (cfg.fc_mp)
3042                 return ip6_route_multipath_del(&cfg);
3043         else
3044                 return ip6_route_del(&cfg);
3045 }
3046
3047 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3048 {
3049         struct fib6_config cfg;
3050         int err;
3051
3052         err = rtm_to_fib6_config(skb, nlh, &cfg);
3053         if (err < 0)
3054                 return err;
3055
3056         if (cfg.fc_mp)
3057                 return ip6_route_multipath_add(&cfg);
3058         else
3059                 return ip6_route_add(&cfg);
3060 }
3061
3062 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3063 {
3064         return NLMSG_ALIGN(sizeof(struct rtmsg))
3065                + nla_total_size(16) /* RTA_SRC */
3066                + nla_total_size(16) /* RTA_DST */
3067                + nla_total_size(16) /* RTA_GATEWAY */
3068                + nla_total_size(16) /* RTA_PREFSRC */
3069                + nla_total_size(4) /* RTA_TABLE */
3070                + nla_total_size(4) /* RTA_IIF */
3071                + nla_total_size(4) /* RTA_OIF */
3072                + nla_total_size(4) /* RTA_PRIORITY */
3073                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3074                + nla_total_size(sizeof(struct rta_cacheinfo))
3075                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3076                + nla_total_size(1) /* RTA_PREF */
3077                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3078 }
3079
3080 static int rt6_fill_node(struct net *net,
3081                          struct sk_buff *skb, struct rt6_info *rt,
3082                          struct in6_addr *dst, struct in6_addr *src,
3083                          int iif, int type, u32 portid, u32 seq,
3084                          int prefix, int nowait, unsigned int flags)
3085 {
3086         u32 metrics[RTAX_MAX];
3087         struct rtmsg *rtm;
3088         struct nlmsghdr *nlh;
3089         long expires;
3090         u32 table;
3091
3092         if (prefix) {   /* user wants prefix routes only */
3093                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3094                         /* success since this is not a prefix route */
3095                         return 1;
3096                 }
3097         }
3098
3099         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3100         if (!nlh)
3101                 return -EMSGSIZE;
3102
3103         rtm = nlmsg_data(nlh);
3104         rtm->rtm_family = AF_INET6;
3105         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3106         rtm->rtm_src_len = rt->rt6i_src.plen;
3107         rtm->rtm_tos = 0;
3108         if (rt->rt6i_table)
3109                 table = rt->rt6i_table->tb6_id;
3110         else
3111                 table = RT6_TABLE_UNSPEC;
3112         rtm->rtm_table = table;
3113         if (nla_put_u32(skb, RTA_TABLE, table))
3114                 goto nla_put_failure;
3115         if (rt->rt6i_flags & RTF_REJECT) {
3116                 switch (rt->dst.error) {
3117                 case -EINVAL:
3118                         rtm->rtm_type = RTN_BLACKHOLE;
3119                         break;
3120                 case -EACCES:
3121                         rtm->rtm_type = RTN_PROHIBIT;
3122                         break;
3123                 case -EAGAIN:
3124                         rtm->rtm_type = RTN_THROW;
3125                         break;
3126                 default:
3127                         rtm->rtm_type = RTN_UNREACHABLE;
3128                         break;
3129                 }
3130         }
3131         else if (rt->rt6i_flags & RTF_LOCAL)
3132                 rtm->rtm_type = RTN_LOCAL;
3133         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3134                 rtm->rtm_type = RTN_LOCAL;
3135         else
3136                 rtm->rtm_type = RTN_UNICAST;
3137         rtm->rtm_flags = 0;
3138         if (!netif_carrier_ok(rt->dst.dev)) {
3139                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3140                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3141                         rtm->rtm_flags |= RTNH_F_DEAD;
3142         }
3143         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3144         rtm->rtm_protocol = rt->rt6i_protocol;
3145         if (rt->rt6i_flags & RTF_DYNAMIC)
3146                 rtm->rtm_protocol = RTPROT_REDIRECT;
3147         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3148                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3149                         rtm->rtm_protocol = RTPROT_RA;
3150                 else
3151                         rtm->rtm_protocol = RTPROT_KERNEL;
3152         }
3153
3154         if (rt->rt6i_flags & RTF_CACHE)
3155                 rtm->rtm_flags |= RTM_F_CLONED;
3156
3157         if (dst) {
3158                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3159                         goto nla_put_failure;
3160                 rtm->rtm_dst_len = 128;
3161         } else if (rtm->rtm_dst_len)
3162                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3163                         goto nla_put_failure;
3164 #ifdef CONFIG_IPV6_SUBTREES
3165         if (src) {
3166                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3167                         goto nla_put_failure;
3168                 rtm->rtm_src_len = 128;
3169         } else if (rtm->rtm_src_len &&
3170                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3171                 goto nla_put_failure;
3172 #endif
3173         if (iif) {
3174 #ifdef CONFIG_IPV6_MROUTE
3175                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3176                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3177                         if (err <= 0) {
3178                                 if (!nowait) {
3179                                         if (err == 0)
3180                                                 return 0;
3181                                         goto nla_put_failure;
3182                                 } else {
3183                                         if (err == -EMSGSIZE)
3184                                                 goto nla_put_failure;
3185                                 }
3186                         }
3187                 } else
3188 #endif
3189                         if (nla_put_u32(skb, RTA_IIF, iif))
3190                                 goto nla_put_failure;
3191         } else if (dst) {
3192                 struct in6_addr saddr_buf;
3193                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3194                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3195                         goto nla_put_failure;
3196         }
3197
3198         if (rt->rt6i_prefsrc.plen) {
3199                 struct in6_addr saddr_buf;
3200                 saddr_buf = rt->rt6i_prefsrc.addr;
3201                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3202                         goto nla_put_failure;
3203         }
3204
3205         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3206         if (rt->rt6i_pmtu)
3207                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3208         if (rtnetlink_put_metrics(skb, metrics) < 0)
3209                 goto nla_put_failure;
3210
3211         if (rt->rt6i_flags & RTF_GATEWAY) {
3212                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3213                         goto nla_put_failure;
3214         }
3215
3216         if (rt->dst.dev &&
3217             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3218                 goto nla_put_failure;
3219         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3220                 goto nla_put_failure;
3221
3222         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3223
3224         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3225                 goto nla_put_failure;
3226
3227         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3228                 goto nla_put_failure;
3229
3230         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3231
3232         nlmsg_end(skb, nlh);
3233         return 0;
3234
3235 nla_put_failure:
3236         nlmsg_cancel(skb, nlh);
3237         return -EMSGSIZE;
3238 }
3239
3240 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3241 {
3242         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3243         int prefix;
3244
3245         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3246                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3247                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3248         } else
3249                 prefix = 0;
3250
3251         return rt6_fill_node(arg->net,
3252                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3253                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3254                      prefix, 0, NLM_F_MULTI);
3255 }
3256
3257 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3258 {
3259         struct net *net = sock_net(in_skb->sk);
3260         struct nlattr *tb[RTA_MAX+1];
3261         struct rt6_info *rt;
3262         struct sk_buff *skb;
3263         struct rtmsg *rtm;
3264         struct flowi6 fl6;
3265         int err, iif = 0, oif = 0;
3266
3267         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3268         if (err < 0)
3269                 goto errout;
3270
3271         err = -EINVAL;
3272         memset(&fl6, 0, sizeof(fl6));
3273
3274         if (tb[RTA_SRC]) {
3275                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3276                         goto errout;
3277
3278                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3279         }
3280
3281         if (tb[RTA_DST]) {
3282                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3283                         goto errout;
3284
3285                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3286         }
3287
3288         if (tb[RTA_IIF])
3289                 iif = nla_get_u32(tb[RTA_IIF]);
3290
3291         if (tb[RTA_OIF])
3292                 oif = nla_get_u32(tb[RTA_OIF]);
3293
3294         if (tb[RTA_MARK])
3295                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3296
3297         if (iif) {
3298                 struct net_device *dev;
3299                 int flags = 0;
3300
3301                 dev = __dev_get_by_index(net, iif);
3302                 if (!dev) {
3303                         err = -ENODEV;
3304                         goto errout;
3305                 }
3306
3307                 fl6.flowi6_iif = iif;
3308
3309                 if (!ipv6_addr_any(&fl6.saddr))
3310                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3311
3312                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3313                                                                flags);
3314         } else {
3315                 fl6.flowi6_oif = oif;
3316
3317                 if (netif_index_is_l3_master(net, oif)) {
3318                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3319                                            FLOWI_FLAG_SKIP_NH_OIF;
3320                 }
3321
3322                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3323         }
3324
3325         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3326         if (!skb) {
3327                 ip6_rt_put(rt);
3328                 err = -ENOBUFS;
3329                 goto errout;
3330         }
3331
3332         /* Reserve room for dummy headers, this skb can pass
3333            through good chunk of routing engine.
3334          */
3335         skb_reset_mac_header(skb);
3336         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3337
3338         skb_dst_set(skb, &rt->dst);
3339
3340         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3341                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3342                             nlh->nlmsg_seq, 0, 0, 0);
3343         if (err < 0) {
3344                 kfree_skb(skb);
3345                 goto errout;
3346         }
3347
3348         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3349 errout:
3350         return err;
3351 }
3352
3353 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3354                      unsigned int nlm_flags)
3355 {
3356         struct sk_buff *skb;
3357         struct net *net = info->nl_net;
3358         u32 seq;
3359         int err;
3360
3361         err = -ENOBUFS;
3362         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3363
3364         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3365         if (!skb)
3366                 goto errout;
3367
3368         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3369                                 event, info->portid, seq, 0, 0, nlm_flags);
3370         if (err < 0) {
3371                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3372                 WARN_ON(err == -EMSGSIZE);
3373                 kfree_skb(skb);
3374                 goto errout;
3375         }
3376         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3377                     info->nlh, gfp_any());
3378         return;
3379 errout:
3380         if (err < 0)
3381                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3382 }
3383
3384 static int ip6_route_dev_notify(struct notifier_block *this,
3385                                 unsigned long event, void *ptr)
3386 {
3387         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3388         struct net *net = dev_net(dev);
3389
3390         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3391                 net->ipv6.ip6_null_entry->dst.dev = dev;
3392                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3393 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3394                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3395                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3396                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3397                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3398 #endif
3399         }
3400
3401         return NOTIFY_OK;
3402 }
3403
3404 /*
3405  *      /proc
3406  */
3407
3408 #ifdef CONFIG_PROC_FS
3409
3410 static const struct file_operations ipv6_route_proc_fops = {
3411         .owner          = THIS_MODULE,
3412         .open           = ipv6_route_open,
3413         .read           = seq_read,
3414         .llseek         = seq_lseek,
3415         .release        = seq_release_net,
3416 };
3417
3418 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3419 {
3420         struct net *net = (struct net *)seq->private;
3421         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3422                    net->ipv6.rt6_stats->fib_nodes,
3423                    net->ipv6.rt6_stats->fib_route_nodes,
3424                    net->ipv6.rt6_stats->fib_rt_alloc,
3425                    net->ipv6.rt6_stats->fib_rt_entries,
3426                    net->ipv6.rt6_stats->fib_rt_cache,
3427                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3428                    net->ipv6.rt6_stats->fib_discarded_routes);
3429
3430         return 0;
3431 }
3432
3433 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3434 {
3435         return single_open_net(inode, file, rt6_stats_seq_show);
3436 }
3437
3438 static const struct file_operations rt6_stats_seq_fops = {
3439         .owner   = THIS_MODULE,
3440         .open    = rt6_stats_seq_open,
3441         .read    = seq_read,
3442         .llseek  = seq_lseek,
3443         .release = single_release_net,
3444 };
3445 #endif  /* CONFIG_PROC_FS */
3446
3447 #ifdef CONFIG_SYSCTL
3448
3449 static
3450 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3451                               void __user *buffer, size_t *lenp, loff_t *ppos)
3452 {
3453         struct net *net;
3454         int delay;
3455         if (!write)
3456                 return -EINVAL;
3457
3458         net = (struct net *)ctl->extra1;
3459         delay = net->ipv6.sysctl.flush_delay;
3460         proc_dointvec(ctl, write, buffer, lenp, ppos);
3461         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3462         return 0;
3463 }
3464
3465 struct ctl_table ipv6_route_table_template[] = {
3466         {
3467                 .procname       =       "flush",
3468                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3469                 .maxlen         =       sizeof(int),
3470                 .mode           =       0200,
3471                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3472         },
3473         {
3474                 .procname       =       "gc_thresh",
3475                 .data           =       &ip6_dst_ops_template.gc_thresh,
3476                 .maxlen         =       sizeof(int),
3477                 .mode           =       0644,
3478                 .proc_handler   =       proc_dointvec,
3479         },
3480         {
3481                 .procname       =       "max_size",
3482                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3483                 .maxlen         =       sizeof(int),
3484                 .mode           =       0644,
3485                 .proc_handler   =       proc_dointvec,
3486         },
3487         {
3488                 .procname       =       "gc_min_interval",
3489                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3490                 .maxlen         =       sizeof(int),
3491                 .mode           =       0644,
3492                 .proc_handler   =       proc_dointvec_jiffies,
3493         },
3494         {
3495                 .procname       =       "gc_timeout",
3496                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3497                 .maxlen         =       sizeof(int),
3498                 .mode           =       0644,
3499                 .proc_handler   =       proc_dointvec_jiffies,
3500         },
3501         {
3502                 .procname       =       "gc_interval",
3503                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3504                 .maxlen         =       sizeof(int),
3505                 .mode           =       0644,
3506                 .proc_handler   =       proc_dointvec_jiffies,
3507         },
3508         {
3509                 .procname       =       "gc_elasticity",
3510                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3511                 .maxlen         =       sizeof(int),
3512                 .mode           =       0644,
3513                 .proc_handler   =       proc_dointvec,
3514         },
3515         {
3516                 .procname       =       "mtu_expires",
3517                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3518                 .maxlen         =       sizeof(int),
3519                 .mode           =       0644,
3520                 .proc_handler   =       proc_dointvec_jiffies,
3521         },
3522         {
3523                 .procname       =       "min_adv_mss",
3524                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3525                 .maxlen         =       sizeof(int),
3526                 .mode           =       0644,
3527                 .proc_handler   =       proc_dointvec,
3528         },
3529         {
3530                 .procname       =       "gc_min_interval_ms",
3531                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3532                 .maxlen         =       sizeof(int),
3533                 .mode           =       0644,
3534                 .proc_handler   =       proc_dointvec_ms_jiffies,
3535         },
3536         { }
3537 };
3538
3539 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3540 {
3541         struct ctl_table *table;
3542
3543         table = kmemdup(ipv6_route_table_template,
3544                         sizeof(ipv6_route_table_template),
3545                         GFP_KERNEL);
3546
3547         if (table) {
3548                 table[0].data = &net->ipv6.sysctl.flush_delay;
3549                 table[0].extra1 = net;
3550                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3551                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3552                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3553                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3554                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3555                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3556                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3557                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3558                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3559
3560                 /* Don't export sysctls to unprivileged users */
3561                 if (net->user_ns != &init_user_ns)
3562                         table[0].procname = NULL;
3563         }
3564
3565         return table;
3566 }
3567 #endif
3568
3569 static int __net_init ip6_route_net_init(struct net *net)
3570 {
3571         int ret = -ENOMEM;
3572
3573         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3574                sizeof(net->ipv6.ip6_dst_ops));
3575
3576         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3577                 goto out_ip6_dst_ops;
3578
3579         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3580                                            sizeof(*net->ipv6.ip6_null_entry),
3581                                            GFP_KERNEL);
3582         if (!net->ipv6.ip6_null_entry)
3583                 goto out_ip6_dst_entries;
3584         net->ipv6.ip6_null_entry->dst.path =
3585                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3586         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3587         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3588                          ip6_template_metrics, true);
3589
3590 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3591         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3592                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3593                                                GFP_KERNEL);
3594         if (!net->ipv6.ip6_prohibit_entry)
3595                 goto out_ip6_null_entry;
3596         net->ipv6.ip6_prohibit_entry->dst.path =
3597                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3598         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3599         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3600                          ip6_template_metrics, true);
3601
3602         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3603                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3604                                                GFP_KERNEL);
3605         if (!net->ipv6.ip6_blk_hole_entry)
3606                 goto out_ip6_prohibit_entry;
3607         net->ipv6.ip6_blk_hole_entry->dst.path =
3608                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3609         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3610         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3611                          ip6_template_metrics, true);
3612 #endif
3613
3614         net->ipv6.sysctl.flush_delay = 0;
3615         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3616         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3617         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3618         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3619         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3620         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3621         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3622
3623         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3624
3625         ret = 0;
3626 out:
3627         return ret;
3628
3629 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3630 out_ip6_prohibit_entry:
3631         kfree(net->ipv6.ip6_prohibit_entry);
3632 out_ip6_null_entry:
3633         kfree(net->ipv6.ip6_null_entry);
3634 #endif
3635 out_ip6_dst_entries:
3636         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3637 out_ip6_dst_ops:
3638         goto out;
3639 }
3640
3641 static void __net_exit ip6_route_net_exit(struct net *net)
3642 {
3643         kfree(net->ipv6.ip6_null_entry);
3644 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3645         kfree(net->ipv6.ip6_prohibit_entry);
3646         kfree(net->ipv6.ip6_blk_hole_entry);
3647 #endif
3648         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3649 }
3650
3651 static int __net_init ip6_route_net_init_late(struct net *net)
3652 {
3653 #ifdef CONFIG_PROC_FS
3654         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3655         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3656 #endif
3657         return 0;
3658 }
3659
3660 static void __net_exit ip6_route_net_exit_late(struct net *net)
3661 {
3662 #ifdef CONFIG_PROC_FS
3663         remove_proc_entry("ipv6_route", net->proc_net);
3664         remove_proc_entry("rt6_stats", net->proc_net);
3665 #endif
3666 }
3667
3668 static struct pernet_operations ip6_route_net_ops = {
3669         .init = ip6_route_net_init,
3670         .exit = ip6_route_net_exit,
3671 };
3672
3673 static int __net_init ipv6_inetpeer_init(struct net *net)
3674 {
3675         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3676
3677         if (!bp)
3678                 return -ENOMEM;
3679         inet_peer_base_init(bp);
3680         net->ipv6.peers = bp;
3681         return 0;
3682 }
3683
3684 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3685 {
3686         struct inet_peer_base *bp = net->ipv6.peers;
3687
3688         net->ipv6.peers = NULL;
3689         inetpeer_invalidate_tree(bp);
3690         kfree(bp);
3691 }
3692
3693 static struct pernet_operations ipv6_inetpeer_ops = {
3694         .init   =       ipv6_inetpeer_init,
3695         .exit   =       ipv6_inetpeer_exit,
3696 };
3697
3698 static struct pernet_operations ip6_route_net_late_ops = {
3699         .init = ip6_route_net_init_late,
3700         .exit = ip6_route_net_exit_late,
3701 };
3702
3703 static struct notifier_block ip6_route_dev_notifier = {
3704         .notifier_call = ip6_route_dev_notify,
3705         .priority = 0,
3706 };
3707
3708 int __init ip6_route_init(void)
3709 {
3710         int ret;
3711         int cpu;
3712
3713         ret = -ENOMEM;
3714         ip6_dst_ops_template.kmem_cachep =
3715                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3716                                   SLAB_HWCACHE_ALIGN, NULL);
3717         if (!ip6_dst_ops_template.kmem_cachep)
3718                 goto out;
3719
3720         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3721         if (ret)
3722                 goto out_kmem_cache;
3723
3724         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3725         if (ret)
3726                 goto out_dst_entries;
3727
3728         ret = register_pernet_subsys(&ip6_route_net_ops);
3729         if (ret)
3730                 goto out_register_inetpeer;
3731
3732         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3733
3734         /* Registering of the loopback is done before this portion of code,
3735          * the loopback reference in rt6_info will not be taken, do it
3736          * manually for init_net */
3737         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3738         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3739   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3740         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3741         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3742         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3743         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3744   #endif
3745         ret = fib6_init();
3746         if (ret)
3747                 goto out_register_subsys;
3748
3749         ret = xfrm6_init();
3750         if (ret)
3751                 goto out_fib6_init;
3752
3753         ret = fib6_rules_init();
3754         if (ret)
3755                 goto xfrm6_init;
3756
3757         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3758         if (ret)
3759                 goto fib6_rules_init;
3760
3761         ret = -ENOBUFS;
3762         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3763             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3764             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3765                 goto out_register_late_subsys;
3766
3767         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3768         if (ret)
3769                 goto out_register_late_subsys;
3770
3771         for_each_possible_cpu(cpu) {
3772                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3773
3774                 INIT_LIST_HEAD(&ul->head);
3775                 spin_lock_init(&ul->lock);
3776         }
3777
3778 out:
3779         return ret;
3780
3781 out_register_late_subsys:
3782         unregister_pernet_subsys(&ip6_route_net_late_ops);
3783 fib6_rules_init:
3784         fib6_rules_cleanup();
3785 xfrm6_init:
3786         xfrm6_fini();
3787 out_fib6_init:
3788         fib6_gc_cleanup();
3789 out_register_subsys:
3790         unregister_pernet_subsys(&ip6_route_net_ops);
3791 out_register_inetpeer:
3792         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3793 out_dst_entries:
3794         dst_entries_destroy(&ip6_dst_blackhole_ops);
3795 out_kmem_cache:
3796         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3797         goto out;
3798 }
3799
3800 void ip6_route_cleanup(void)
3801 {
3802         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3803         unregister_pernet_subsys(&ip6_route_net_late_ops);
3804         fib6_rules_cleanup();
3805         xfrm6_fini();
3806         fib6_gc_cleanup();
3807         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3808         unregister_pernet_subsys(&ip6_route_net_ops);
3809         dst_entries_destroy(&ip6_dst_blackhole_ops);
3810         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3811 }