net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64
  65 #include <asm/uaccess.h>
  66
  67 #ifdef CONFIG_SYSCTL
  68 #include <linux/sysctl.h>
  69 #endif
  70
  71 enum rt6_nud_state {
  72         RT6_NUD_FAIL_HARD = -3,
  73         RT6_NUD_FAIL_PROBE = -2,
  74         RT6_NUD_FAIL_DO_RR = -1,
  75         RT6_NUD_SUCCEED = 1
  76 };
  77
  78 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  79 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  80 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  81 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  82 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  83 static void             ip6_dst_destroy(struct dst_entry *);
  84 static void             ip6_dst_ifdown(struct dst_entry *,
  85                                        struct net_device *dev, int how);
  86 static int               ip6_dst_gc(struct dst_ops *ops);
  87
  88 static int              ip6_pkt_discard(struct sk_buff *skb);
  89 static int              ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb);
  90 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  91 static int              ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb);
  92 static void             ip6_link_failure(struct sk_buff *skb);
  93 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  94                                            struct sk_buff *skb, u32 mtu);
  95 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  96                                         struct sk_buff *skb);
  97 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
  98 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
  99
 100 #ifdef CONFIG_IPV6_ROUTE_INFO
 101 static struct rt6_info *rt6_add_route_info(struct net *net,
 102                                            const struct in6_addr *prefix, int prefixlen,
 103                                            const struct in6_addr *gwaddr, int ifindex,
 104                                            unsigned int pref);
 105 static struct rt6_info *rt6_get_route_info(struct net *net,
 106                                            const struct in6_addr *prefix, int prefixlen,
 107                                            const struct in6_addr *gwaddr, int ifindex);
 108 #endif
 109
 110 struct uncached_list {
 111         spinlock_t              lock;
 112         struct list_head        head;
 113 };
 114
 115 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 116
 117 static void rt6_uncached_list_add(struct rt6_info *rt)
 118 {
 119         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 120
 121         rt->dst.flags |= DST_NOCACHE;
 122         rt->rt6i_uncached_list = ul;
 123
 124         spin_lock_bh(&ul->lock);
 125         list_add_tail(&rt->rt6i_uncached, &ul->head);
 126         spin_unlock_bh(&ul->lock);
 127 }
 128
 129 static void rt6_uncached_list_del(struct rt6_info *rt)
 130 {
 131         if (!list_empty(&rt->rt6i_uncached)) {
 132                 struct uncached_list *ul = rt->rt6i_uncached_list;
 133
 134                 spin_lock_bh(&ul->lock);
 135                 list_del(&rt->rt6i_uncached);
 136                 spin_unlock_bh(&ul->lock);
 137         }
 138 }
 139
 140 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 141 {
 142         struct net_device *loopback_dev = net->loopback_dev;
 143         int cpu;
 144
 145         for_each_possible_cpu(cpu) {
 146                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 147                 struct rt6_info *rt;
 148
 149                 spin_lock_bh(&ul->lock);
 150                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 151                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 152                         struct net_device *rt_dev = rt->dst.dev;
 153
 154                         if (rt_idev && (rt_idev->dev == dev || !dev) &&
 155                             rt_idev->dev != loopback_dev) {
 156                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 157                                 in6_dev_put(rt_idev);
 158                         }
 159
 160                         if (rt_dev && (rt_dev == dev || !dev) &&
 161                             rt_dev != loopback_dev) {
 162                                 rt->dst.dev = loopback_dev;
 163                                 dev_hold(rt->dst.dev);
 164                                 dev_put(rt_dev);
 165                         }
 166                 }
 167                 spin_unlock_bh(&ul->lock);
 168         }
 169 }
 170
 171 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 172 {
 173         return dst_metrics_write_ptr(rt->dst.from);
 174 }
 175
 176 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 177 {
 178         struct rt6_info *rt = (struct rt6_info *)dst;
 179
 180         if (rt->rt6i_flags & RTF_PCPU)
 181                 return rt6_pcpu_cow_metrics(rt);
 182         else if (rt->rt6i_flags & RTF_CACHE)
 183                 return NULL;
 184         else
 185                 return dst_cow_metrics_generic(dst, old);
 186 }
 187
 188 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 189                                              struct sk_buff *skb,
 190                                              const void *daddr)
 191 {
 192         struct in6_addr *p = &rt->rt6i_gateway;
 193
 194         if (!ipv6_addr_any(p))
 195                 return (const void *) p;
 196         else if (skb)
 197                 return &ipv6_hdr(skb)->daddr;
 198         return daddr;
 199 }
 200
 201 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 202                                           struct sk_buff *skb,
 203                                           const void *daddr)
 204 {
 205         struct rt6_info *rt = (struct rt6_info *) dst;
 206         struct neighbour *n;
 207
 208         daddr = choose_neigh_daddr(rt, skb, daddr);
 209         n = __ipv6_neigh_lookup(dst->dev, daddr);
 210         if (n)
 211                 return n;
 212         return neigh_create(&nd_tbl, daddr, dst->dev);
 213 }
 214
 215 static struct dst_ops ip6_dst_ops_template = {
 216         .family                 =       AF_INET6,
 217         .gc                     =       ip6_dst_gc,
 218         .gc_thresh              =       1024,
 219         .check                  =       ip6_dst_check,
 220         .default_advmss         =       ip6_default_advmss,
 221         .mtu                    =       ip6_mtu,
 222         .cow_metrics            =       ipv6_cow_metrics,
 223         .destroy                =       ip6_dst_destroy,
 224         .ifdown                 =       ip6_dst_ifdown,
 225         .negative_advice        =       ip6_negative_advice,
 226         .link_failure           =       ip6_link_failure,
 227         .update_pmtu            =       ip6_rt_update_pmtu,
 228         .redirect               =       rt6_do_redirect,
 229         .local_out              =       __ip6_local_out,
 230         .neigh_lookup           =       ip6_neigh_lookup,
 231 };
 232
 233 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 234 {
 235         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 236
 237         return mtu ? : dst->dev->mtu;
 238 }
 239
 240 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 241                                          struct sk_buff *skb, u32 mtu)
 242 {
 243 }
 244
 245 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 246                                       struct sk_buff *skb)
 247 {
 248 }
 249
 250 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
 251                                          unsigned long old)
 252 {
 253         return NULL;
 254 }
 255
 256 static struct dst_ops ip6_dst_blackhole_ops = {
 257         .family                 =       AF_INET6,
 258         .destroy                =       ip6_dst_destroy,
 259         .check                  =       ip6_dst_check,
 260         .mtu                    =       ip6_blackhole_mtu,
 261         .default_advmss         =       ip6_default_advmss,
 262         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 263         .redirect               =       ip6_rt_blackhole_redirect,
 264         .cow_metrics            =       ip6_rt_blackhole_cow_metrics,
 265         .neigh_lookup           =       ip6_neigh_lookup,
 266 };
 267
 268 static const u32 ip6_template_metrics[RTAX_MAX] = {
 269         [RTAX_HOPLIMIT - 1] = 0,
 270 };
 271
 272 static const struct rt6_info ip6_null_entry_template = {
 273         .dst = {
 274                 .__refcnt       = ATOMIC_INIT(1),
 275                 .__use          = 1,
 276                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 277                 .error          = -ENETUNREACH,
 278                 .input          = ip6_pkt_discard,
 279                 .output         = ip6_pkt_discard_out,
 280         },
 281         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 282         .rt6i_protocol  = RTPROT_KERNEL,
 283         .rt6i_metric    = ~(u32) 0,
 284         .rt6i_ref       = ATOMIC_INIT(1),
 285 };
 286
 287 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 288
 289 static const struct rt6_info ip6_prohibit_entry_template = {
 290         .dst = {
 291                 .__refcnt       = ATOMIC_INIT(1),
 292                 .__use          = 1,
 293                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 294                 .error          = -EACCES,
 295                 .input          = ip6_pkt_prohibit,
 296                 .output         = ip6_pkt_prohibit_out,
 297         },
 298         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 299         .rt6i_protocol  = RTPROT_KERNEL,
 300         .rt6i_metric    = ~(u32) 0,
 301         .rt6i_ref       = ATOMIC_INIT(1),
 302 };
 303
 304 static const struct rt6_info ip6_blk_hole_entry_template = {
 305         .dst = {
 306                 .__refcnt       = ATOMIC_INIT(1),
 307                 .__use          = 1,
 308                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 309                 .error          = -EINVAL,
 310                 .input          = dst_discard,
 311                 .output         = dst_discard_sk,
 312         },
 313         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 314         .rt6i_protocol  = RTPROT_KERNEL,
 315         .rt6i_metric    = ~(u32) 0,
 316         .rt6i_ref       = ATOMIC_INIT(1),
 317 };
 318
 319 #endif
 320
 321 /* allocate dst with ip6_dst_ops */
 322 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 323                                         struct net_device *dev,
 324                                         int flags)
 325 {
 326         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 327                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 328
 329         if (rt) {
 330                 struct dst_entry *dst = &rt->dst;
 331
 332                 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 333                 INIT_LIST_HEAD(&rt->rt6i_siblings);
 334                 INIT_LIST_HEAD(&rt->rt6i_uncached);
 335         }
 336         return rt;
 337 }
 338
 339 static struct rt6_info *ip6_dst_alloc(struct net *net,
 340                                       struct net_device *dev,
 341                                       int flags)
 342 {
 343         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 344
 345         if (rt) {
 346                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 347                 if (rt->rt6i_pcpu) {
 348                         int cpu;
 349
 350                         for_each_possible_cpu(cpu) {
 351                                 struct rt6_info **p;
 352
 353                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 354                                 /* no one shares rt */
 355                                 *p =  NULL;
 356                         }
 357                 } else {
 358                         dst_destroy((struct dst_entry *)rt);
 359                         return NULL;
 360                 }
 361         }
 362
 363         return rt;
 364 }
 365
 366 static void ip6_dst_destroy(struct dst_entry *dst)
 367 {
 368         struct rt6_info *rt = (struct rt6_info *)dst;
 369         struct dst_entry *from = dst->from;
 370         struct inet6_dev *idev;
 371
 372         dst_destroy_metrics_generic(dst);
 373         free_percpu(rt->rt6i_pcpu);
 374         rt6_uncached_list_del(rt);
 375
 376         idev = rt->rt6i_idev;
 377         if (idev) {
 378                 rt->rt6i_idev = NULL;
 379                 in6_dev_put(idev);
 380         }
 381
 382         dst->from = NULL;
 383         dst_release(from);
 384 }
 385
 386 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 387                            int how)
 388 {
 389         struct rt6_info *rt = (struct rt6_info *)dst;
 390         struct inet6_dev *idev = rt->rt6i_idev;
 391         struct net_device *loopback_dev =
 392                 dev_net(dev)->loopback_dev;
 393
 394         if (dev != loopback_dev) {
 395                 if (idev && idev->dev == dev) {
 396                         struct inet6_dev *loopback_idev =
 397                                 in6_dev_get(loopback_dev);
 398                         if (loopback_idev) {
 399                                 rt->rt6i_idev = loopback_idev;
 400                                 in6_dev_put(idev);
 401                         }
 402                 }
 403         }
 404 }
 405
 406 static bool rt6_check_expired(const struct rt6_info *rt)
 407 {
 408         if (rt->rt6i_flags & RTF_EXPIRES) {
 409                 if (time_after(jiffies, rt->dst.expires))
 410                         return true;
 411         } else if (rt->dst.from) {
 412                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 413         }
 414         return false;
 415 }
 416
 417 /* Multipath route selection:
 418  *   Hash based function using packet header and flowlabel.
 419  * Adapted from fib_info_hashfn()
 420  */
 421 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 422                                const struct flowi6 *fl6)
 423 {
 424         unsigned int val = fl6->flowi6_proto;
 425
 426         val ^= ipv6_addr_hash(&fl6->daddr);
 427         val ^= ipv6_addr_hash(&fl6->saddr);
 428
 429         /* Work only if this not encapsulated */
 430         switch (fl6->flowi6_proto) {
 431         case IPPROTO_UDP:
 432         case IPPROTO_TCP:
 433         case IPPROTO_SCTP:
 434                 val ^= (__force u16)fl6->fl6_sport;
 435                 val ^= (__force u16)fl6->fl6_dport;
 436                 break;
 437
 438         case IPPROTO_ICMPV6:
 439                 val ^= (__force u16)fl6->fl6_icmp_type;
 440                 val ^= (__force u16)fl6->fl6_icmp_code;
 441                 break;
 442         }
 443         /* RFC6438 recommands to use flowlabel */
 444         val ^= (__force u32)fl6->flowlabel;
 445
 446         /* Perhaps, we need to tune, this function? */
 447         val = val ^ (val >> 7) ^ (val >> 12);
 448         return val % candidate_count;
 449 }
 450
 451 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 452                                              struct flowi6 *fl6, int oif,
 453                                              int strict)
 454 {
 455         struct rt6_info *sibling, *next_sibling;
 456         int route_choosen;
 457
 458         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 459         /* Don't change the route, if route_choosen == 0
 460          * (siblings does not include ourself)
 461          */
 462         if (route_choosen)
 463                 list_for_each_entry_safe(sibling, next_sibling,
 464                                 &match->rt6i_siblings, rt6i_siblings) {
 465                         route_choosen--;
 466                         if (route_choosen == 0) {
 467                                 if (rt6_score_route(sibling, oif, strict) < 0)
 468                                         break;
 469                                 match = sibling;
 470                                 break;
 471                         }
 472                 }
 473         return match;
 474 }
 475
 476 /*
 477  *      Route lookup. Any table->tb6_lock is implied.
 478  */
 479
 480 static inline struct rt6_info *rt6_device_match(struct net *net,
 481                                                     struct rt6_info *rt,
 482                                                     const struct in6_addr *saddr,
 483                                                     int oif,
 484                                                     int flags)
 485 {
 486         struct rt6_info *local = NULL;
 487         struct rt6_info *sprt;
 488
 489         if (!oif && ipv6_addr_any(saddr))
 490                 goto out;
 491
 492         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 493                 struct net_device *dev = sprt->dst.dev;
 494
 495                 if (oif) {
 496                         if (dev->ifindex == oif)
 497                                 return sprt;
 498                         if (dev->flags & IFF_LOOPBACK) {
 499                                 if (!sprt->rt6i_idev ||
 500                                     sprt->rt6i_idev->dev->ifindex != oif) {
 501                                         if (flags & RT6_LOOKUP_F_IFACE && oif)
 502                                                 continue;
 503                                         if (local && (!oif ||
 504                                                       local->rt6i_idev->dev->ifindex == oif))
 505                                                 continue;
 506                                 }
 507                                 local = sprt;
 508                         }
 509                 } else {
 510                         if (ipv6_chk_addr(net, saddr, dev,
 511                                           flags & RT6_LOOKUP_F_IFACE))
 512                                 return sprt;
 513                 }
 514         }
 515
 516         if (oif) {
 517                 if (local)
 518                         return local;
 519
 520                 if (flags & RT6_LOOKUP_F_IFACE)
 521                         return net->ipv6.ip6_null_entry;
 522         }
 523 out:
 524         return rt;
 525 }
 526
 527 #ifdef CONFIG_IPV6_ROUTER_PREF
 528 struct __rt6_probe_work {
 529         struct work_struct work;
 530         struct in6_addr target;
 531         struct net_device *dev;
 532 };
 533
 534 static void rt6_probe_deferred(struct work_struct *w)
 535 {
 536         struct in6_addr mcaddr;
 537         struct __rt6_probe_work *work =
 538                 container_of(w, struct __rt6_probe_work, work);
 539
 540         addrconf_addr_solict_mult(&work->target, &mcaddr);
 541         ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL, NULL);
 542         dev_put(work->dev);
 543         kfree(work);
 544 }
 545
 546 static void rt6_probe(struct rt6_info *rt)
 547 {
 548         struct __rt6_probe_work *work;
 549         struct neighbour *neigh;
 550         /*
 551          * Okay, this does not seem to be appropriate
 552          * for now, however, we need to check if it
 553          * is really so; aka Router Reachability Probing.
 554          *
 555          * Router Reachability Probe MUST be rate-limited
 556          * to no more than one per minute.
 557          */
 558         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 559                 return;
 560         rcu_read_lock_bh();
 561         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 562         if (neigh) {
 563                 if (neigh->nud_state & NUD_VALID)
 564                         goto out;
 565
 566                 work = NULL;
 567                 write_lock(&neigh->lock);
 568                 if (!(neigh->nud_state & NUD_VALID) &&
 569                     time_after(jiffies,
 570                                neigh->updated +
 571                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 572                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 573                         if (work)
 574                                 __neigh_set_probe_once(neigh);
 575                 }
 576                 write_unlock(&neigh->lock);
 577         } else {
 578                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 579         }
 580
 581         if (work) {
 582                 INIT_WORK(&work->work, rt6_probe_deferred);
 583                 work->target = rt->rt6i_gateway;
 584                 dev_hold(rt->dst.dev);
 585                 work->dev = rt->dst.dev;
 586                 schedule_work(&work->work);
 587         }
 588
 589 out:
 590         rcu_read_unlock_bh();
 591 }
 592 #else
 593 static inline void rt6_probe(struct rt6_info *rt)
 594 {
 595 }
 596 #endif
 597
 598 /*
 599  * Default Router Selection (RFC 2461 6.3.6)
 600  */
 601 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 602 {
 603         struct net_device *dev = rt->dst.dev;
 604         if (!oif || dev->ifindex == oif)
 605                 return 2;
 606         if ((dev->flags & IFF_LOOPBACK) &&
 607             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 608                 return 1;
 609         return 0;
 610 }
 611
 612 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 613 {
 614         struct neighbour *neigh;
 615         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 616
 617         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 618             !(rt->rt6i_flags & RTF_GATEWAY))
 619                 return RT6_NUD_SUCCEED;
 620
 621         rcu_read_lock_bh();
 622         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 623         if (neigh) {
 624                 read_lock(&neigh->lock);
 625                 if (neigh->nud_state & NUD_VALID)
 626                         ret = RT6_NUD_SUCCEED;
 627 #ifdef CONFIG_IPV6_ROUTER_PREF
 628                 else if (!(neigh->nud_state & NUD_FAILED))
 629                         ret = RT6_NUD_SUCCEED;
 630                 else
 631                         ret = RT6_NUD_FAIL_PROBE;
 632 #endif
 633                 read_unlock(&neigh->lock);
 634         } else {
 635                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 636                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 637         }
 638         rcu_read_unlock_bh();
 639
 640         return ret;
 641 }
 642
 643 static int rt6_score_route(struct rt6_info *rt, int oif,
 644                            int strict)
 645 {
 646         int m;
 647
 648         m = rt6_check_dev(rt, oif);
 649         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 650                 return RT6_NUD_FAIL_HARD;
 651 #ifdef CONFIG_IPV6_ROUTER_PREF
 652         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 653 #endif
 654         if (strict & RT6_LOOKUP_F_REACHABLE) {
 655                 int n = rt6_check_neigh(rt);
 656                 if (n < 0)
 657                         return n;
 658         }
 659         return m;
 660 }
 661
 662 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 663                                    int *mpri, struct rt6_info *match,
 664                                    bool *do_rr)
 665 {
 666         int m;
 667         bool match_do_rr = false;
 668         struct inet6_dev *idev = rt->rt6i_idev;
 669         struct net_device *dev = rt->dst.dev;
 670
 671         if (dev && !netif_carrier_ok(dev) &&
 672             idev->cnf.ignore_routes_with_linkdown)
 673                 goto out;
 674
 675         if (rt6_check_expired(rt))
 676                 goto out;
 677
 678         m = rt6_score_route(rt, oif, strict);
 679         if (m == RT6_NUD_FAIL_DO_RR) {
 680                 match_do_rr = true;
 681                 m = 0; /* lowest valid score */
 682         } else if (m == RT6_NUD_FAIL_HARD) {
 683                 goto out;
 684         }
 685
 686         if (strict & RT6_LOOKUP_F_REACHABLE)
 687                 rt6_probe(rt);
 688
 689         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 690         if (m > *mpri) {
 691                 *do_rr = match_do_rr;
 692                 *mpri = m;
 693                 match = rt;
 694         }
 695 out:
 696         return match;
 697 }
 698
 699 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 700                                      struct rt6_info *rr_head,
 701                                      u32 metric, int oif, int strict,
 702                                      bool *do_rr)
 703 {
 704         struct rt6_info *rt, *match, *cont;
 705         int mpri = -1;
 706
 707         match = NULL;
 708         cont = NULL;
 709         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 710                 if (rt->rt6i_metric != metric) {
 711                         cont = rt;
 712                         break;
 713                 }
 714
 715                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 716         }
 717
 718         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 719                 if (rt->rt6i_metric != metric) {
 720                         cont = rt;
 721                         break;
 722                 }
 723
 724                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 725         }
 726
 727         if (match || !cont)
 728                 return match;
 729
 730         for (rt = cont; rt; rt = rt->dst.rt6_next)
 731                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 732
 733         return match;
 734 }
 735
 736 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 737 {
 738         struct rt6_info *match, *rt0;
 739         struct net *net;
 740         bool do_rr = false;
 741
 742         rt0 = fn->rr_ptr;
 743         if (!rt0)
 744                 fn->rr_ptr = rt0 = fn->leaf;
 745
 746         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 747                              &do_rr);
 748
 749         if (do_rr) {
 750                 struct rt6_info *next = rt0->dst.rt6_next;
 751
 752                 /* no entries matched; do round-robin */
 753                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 754                         next = fn->leaf;
 755
 756                 if (next != rt0)
 757                         fn->rr_ptr = next;
 758         }
 759
 760         net = dev_net(rt0->dst.dev);
 761         return match ? match : net->ipv6.ip6_null_entry;
 762 }
 763
 764 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 765 {
 766         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 767 }
 768
 769 #ifdef CONFIG_IPV6_ROUTE_INFO
 770 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 771                   const struct in6_addr *gwaddr)
 772 {
 773         struct net *net = dev_net(dev);
 774         struct route_info *rinfo = (struct route_info *) opt;
 775         struct in6_addr prefix_buf, *prefix;
 776         unsigned int pref;
 777         unsigned long lifetime;
 778         struct rt6_info *rt;
 779
 780         if (len < sizeof(struct route_info)) {
 781                 return -EINVAL;
 782         }
 783
 784         /* Sanity check for prefix_len and length */
 785         if (rinfo->length > 3) {
 786                 return -EINVAL;
 787         } else if (rinfo->prefix_len > 128) {
 788                 return -EINVAL;
 789         } else if (rinfo->prefix_len > 64) {
 790                 if (rinfo->length < 2) {
 791                         return -EINVAL;
 792                 }
 793         } else if (rinfo->prefix_len > 0) {
 794                 if (rinfo->length < 1) {
 795                         return -EINVAL;
 796                 }
 797         }
 798
 799         pref = rinfo->route_pref;
 800         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 801                 return -EINVAL;
 802
 803         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 804
 805         if (rinfo->length == 3)
 806                 prefix = (struct in6_addr *)rinfo->prefix;
 807         else {
 808                 /* this function is safe */
 809                 ipv6_addr_prefix(&prefix_buf,
 810                                  (struct in6_addr *)rinfo->prefix,
 811                                  rinfo->prefix_len);
 812                 prefix = &prefix_buf;
 813         }
 814
 815         if (rinfo->prefix_len == 0)
 816                 rt = rt6_get_dflt_router(gwaddr, dev);
 817         else
 818                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 819                                         gwaddr, dev->ifindex);
 820
 821         if (rt && !lifetime) {
 822                 ip6_del_rt(rt);
 823                 rt = NULL;
 824         }
 825
 826         if (!rt && lifetime)
 827                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 828                                         pref);
 829         else if (rt)
 830                 rt->rt6i_flags = RTF_ROUTEINFO |
 831                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 832
 833         if (rt) {
 834                 if (!addrconf_finite_timeout(lifetime))
 835                         rt6_clean_expires(rt);
 836                 else
 837                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 838
 839                 ip6_rt_put(rt);
 840         }
 841         return 0;
 842 }
 843 #endif
 844
 845 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 846                                         struct in6_addr *saddr)
 847 {
 848         struct fib6_node *pn;
 849         while (1) {
 850                 if (fn->fn_flags & RTN_TL_ROOT)
 851                         return NULL;
 852                 pn = fn->parent;
 853                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 854                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 855                 else
 856                         fn = pn;
 857                 if (fn->fn_flags & RTN_RTINFO)
 858                         return fn;
 859         }
 860 }
 861
 862 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 863                                              struct fib6_table *table,
 864                                              struct flowi6 *fl6, int flags)
 865 {
 866         struct fib6_node *fn;
 867         struct rt6_info *rt;
 868
 869         read_lock_bh(&table->tb6_lock);
 870         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 871 restart:
 872         rt = fn->leaf;
 873         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 874         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 875                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 876         if (rt == net->ipv6.ip6_null_entry) {
 877                 fn = fib6_backtrack(fn, &fl6->saddr);
 878                 if (fn)
 879                         goto restart;
 880         }
 881         dst_use(&rt->dst, jiffies);
 882         read_unlock_bh(&table->tb6_lock);
 883         return rt;
 884
 885 }
 886
 887 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 888                                     int flags)
 889 {
 890         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 891 }
 892 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 893
 894 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 895                             const struct in6_addr *saddr, int oif, int strict)
 896 {
 897         struct flowi6 fl6 = {
 898                 .flowi6_oif = oif,
 899                 .daddr = *daddr,
 900         };
 901         struct dst_entry *dst;
 902         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 903
 904         if (saddr) {
 905                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 906                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 907         }
 908
 909         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 910         if (dst->error == 0)
 911                 return (struct rt6_info *) dst;
 912
 913         dst_release(dst);
 914
 915         return NULL;
 916 }
 917 EXPORT_SYMBOL(rt6_lookup);
 918
 919 /* ip6_ins_rt is called with FREE table->tb6_lock.
 920    It takes new route entry, the addition fails by any reason the
 921    route is freed. In any case, if caller does not hold it, it may
 922    be destroyed.
 923  */
 924
 925 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 926                         struct mx6_config *mxc)
 927 {
 928         int err;
 929         struct fib6_table *table;
 930
 931         table = rt->rt6i_table;
 932         write_lock_bh(&table->tb6_lock);
 933         err = fib6_add(&table->tb6_root, rt, info, mxc);
 934         write_unlock_bh(&table->tb6_lock);
 935
 936         return err;
 937 }
 938
 939 int ip6_ins_rt(struct rt6_info *rt)
 940 {
 941         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 942         struct mx6_config mxc = { .mx = NULL, };
 943
 944         return __ip6_ins_rt(rt, &info, &mxc);
 945 }
 946
 947 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 948                                            const struct in6_addr *daddr,
 949                                            const struct in6_addr *saddr)
 950 {
 951         struct rt6_info *rt;
 952
 953         /*
 954          *      Clone the route.
 955          */
 956
 957         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 958                 ort = (struct rt6_info *)ort->dst.from;
 959
 960         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 961
 962         if (!rt)
 963                 return NULL;
 964
 965         ip6_rt_copy_init(rt, ort);
 966         rt->rt6i_flags |= RTF_CACHE;
 967         rt->rt6i_metric = 0;
 968         rt->dst.flags |= DST_HOST;
 969         rt->rt6i_dst.addr = *daddr;
 970         rt->rt6i_dst.plen = 128;
 971
 972         if (!rt6_is_gw_or_nonexthop(ort)) {
 973                 if (ort->rt6i_dst.plen != 128 &&
 974                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 975                         rt->rt6i_flags |= RTF_ANYCAST;
 976 #ifdef CONFIG_IPV6_SUBTREES
 977                 if (rt->rt6i_src.plen && saddr) {
 978                         rt->rt6i_src.addr = *saddr;
 979                         rt->rt6i_src.plen = 128;
 980                 }
 981 #endif
 982         }
 983
 984         return rt;
 985 }
 986
 987 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 988 {
 989         struct rt6_info *pcpu_rt;
 990
 991         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 992                                   rt->dst.dev, rt->dst.flags);
 993
 994         if (!pcpu_rt)
 995                 return NULL;
 996         ip6_rt_copy_init(pcpu_rt, rt);
 997         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 998         pcpu_rt->rt6i_flags |= RTF_PCPU;
 999         return pcpu_rt;
1000 }
1001
1002 /* It should be called with read_lock_bh(&tb6_lock) acquired */
1003 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
1004 {
1005         struct rt6_info *pcpu_rt, **p;
1006
1007         p = this_cpu_ptr(rt->rt6i_pcpu);
1008         pcpu_rt = *p;
1009
1010         if (pcpu_rt) {
1011                 dst_hold(&pcpu_rt->dst);
1012                 rt6_dst_from_metrics_check(pcpu_rt);
1013         }
1014         return pcpu_rt;
1015 }
1016
1017 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1018 {
1019         struct fib6_table *table = rt->rt6i_table;
1020         struct rt6_info *pcpu_rt, *prev, **p;
1021
1022         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1023         if (!pcpu_rt) {
1024                 struct net *net = dev_net(rt->dst.dev);
1025
1026                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1027                 return net->ipv6.ip6_null_entry;
1028         }
1029
1030         read_lock_bh(&table->tb6_lock);
1031         if (rt->rt6i_pcpu) {
1032                 p = this_cpu_ptr(rt->rt6i_pcpu);
1033                 prev = cmpxchg(p, NULL, pcpu_rt);
1034                 if (prev) {
1035                         /* If someone did it before us, return prev instead */
1036                         dst_destroy(&pcpu_rt->dst);
1037                         pcpu_rt = prev;
1038                 }
1039         } else {
1040                 /* rt has been removed from the fib6 tree
1041                  * before we have a chance to acquire the read_lock.
1042                  * In this case, don't brother to create a pcpu rt
1043                  * since rt is going away anyway.  The next
1044                  * dst_check() will trigger a re-lookup.
1045                  */
1046                 dst_destroy(&pcpu_rt->dst);
1047                 pcpu_rt = rt;
1048         }
1049         dst_hold(&pcpu_rt->dst);
1050         rt6_dst_from_metrics_check(pcpu_rt);
1051         read_unlock_bh(&table->tb6_lock);
1052         return pcpu_rt;
1053 }
1054
1055 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1056                                       struct flowi6 *fl6, int flags)
1057 {
1058         struct fib6_node *fn, *saved_fn;
1059         struct rt6_info *rt;
1060         int strict = 0;
1061
1062         strict |= flags & RT6_LOOKUP_F_IFACE;
1063         if (net->ipv6.devconf_all->forwarding == 0)
1064                 strict |= RT6_LOOKUP_F_REACHABLE;
1065
1066         read_lock_bh(&table->tb6_lock);
1067
1068         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1069         saved_fn = fn;
1070
1071 redo_rt6_select:
1072         rt = rt6_select(fn, oif, strict);
1073         if (rt->rt6i_nsiblings)
1074                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1075         if (rt == net->ipv6.ip6_null_entry) {
1076                 fn = fib6_backtrack(fn, &fl6->saddr);
1077                 if (fn)
1078                         goto redo_rt6_select;
1079                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1080                         /* also consider unreachable route */
1081                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1082                         fn = saved_fn;
1083                         goto redo_rt6_select;
1084                 }
1085         }
1086
1087
1088         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1089                 dst_use(&rt->dst, jiffies);
1090                 read_unlock_bh(&table->tb6_lock);
1091
1092                 rt6_dst_from_metrics_check(rt);
1093                 return rt;
1094         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1095                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1096                 /* Create a RTF_CACHE clone which will not be
1097                  * owned by the fib6 tree.  It is for the special case where
1098                  * the daddr in the skb during the neighbor look-up is different
1099                  * from the fl6->daddr used to look-up route here.
1100                  */
1101
1102                 struct rt6_info *uncached_rt;
1103
1104                 dst_use(&rt->dst, jiffies);
1105                 read_unlock_bh(&table->tb6_lock);
1106
1107                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1108                 dst_release(&rt->dst);
1109
1110                 if (uncached_rt)
1111                         rt6_uncached_list_add(uncached_rt);
1112                 else
1113                         uncached_rt = net->ipv6.ip6_null_entry;
1114
1115                 dst_hold(&uncached_rt->dst);
1116                 return uncached_rt;
1117
1118         } else {
1119                 /* Get a percpu copy */
1120
1121                 struct rt6_info *pcpu_rt;
1122
1123                 rt->dst.lastuse = jiffies;
1124                 rt->dst.__use++;
1125                 pcpu_rt = rt6_get_pcpu_route(rt);
1126
1127                 if (pcpu_rt) {
1128                         read_unlock_bh(&table->tb6_lock);
1129                 } else {
1130                         /* We have to do the read_unlock first
1131                          * because rt6_make_pcpu_route() may trigger
1132                          * ip6_dst_gc() which will take the write_lock.
1133                          */
1134                         dst_hold(&rt->dst);
1135                         read_unlock_bh(&table->tb6_lock);
1136                         pcpu_rt = rt6_make_pcpu_route(rt);
1137                         dst_release(&rt->dst);
1138                 }
1139
1140                 return pcpu_rt;
1141
1142         }
1143 }
1144
1145 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1146                                             struct flowi6 *fl6, int flags)
1147 {
1148         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1149 }
1150
1151 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1152                                                 struct net_device *dev,
1153                                                 struct flowi6 *fl6, int flags)
1154 {
1155         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1156                 flags |= RT6_LOOKUP_F_IFACE;
1157
1158         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1159 }
1160
1161 void ip6_route_input(struct sk_buff *skb)
1162 {
1163         const struct ipv6hdr *iph = ipv6_hdr(skb);
1164         struct net *net = dev_net(skb->dev);
1165         int flags = RT6_LOOKUP_F_HAS_SADDR;
1166         struct ip_tunnel_info *tun_info;
1167         struct flowi6 fl6 = {
1168                 .flowi6_iif = skb->dev->ifindex,
1169                 .daddr = iph->daddr,
1170                 .saddr = iph->saddr,
1171                 .flowlabel = ip6_flowinfo(iph),
1172                 .flowi6_mark = skb->mark,
1173                 .flowi6_proto = iph->nexthdr,
1174         };
1175
1176         tun_info = skb_tunnel_info(skb);
1177         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1178                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1179         skb_dst_drop(skb);
1180         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1181 }
1182
1183 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1184                                              struct flowi6 *fl6, int flags)
1185 {
1186         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1187 }
1188
1189 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1190                                     struct flowi6 *fl6)
1191 {
1192         int flags = 0;
1193
1194         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1195
1196         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1197             fl6->flowi6_oif)
1198                 flags |= RT6_LOOKUP_F_IFACE;
1199
1200         if (!ipv6_addr_any(&fl6->saddr))
1201                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1202         else if (sk)
1203                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1204
1205         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1206 }
1207 EXPORT_SYMBOL(ip6_route_output);
1208
1209 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1210 {
1211         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1212         struct dst_entry *new = NULL;
1213
1214         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1215         if (rt) {
1216                 new = &rt->dst;
1217
1218                 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1219
1220                 new->__use = 1;
1221                 new->input = dst_discard;
1222                 new->output = dst_discard_sk;
1223
1224                 if (dst_metrics_read_only(&ort->dst))
1225                         new->_metrics = ort->dst._metrics;
1226                 else
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;
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 (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1273             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1274                 return &rt->dst;
1275         else
1276                 return NULL;
1277 }
1278
1279 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1280 {
1281         struct rt6_info *rt;
1282
1283         rt = (struct rt6_info *) dst;
1284
1285         /* All IPV6 dsts are created with ->obsolete set to the value
1286          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1287          * into this function always.
1288          */
1289
1290         rt6_dst_from_metrics_check(rt);
1291
1292         if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1293                 return rt6_dst_from_check(rt, cookie);
1294         else
1295                 return rt6_check(rt, cookie);
1296 }
1297
1298 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1299 {
1300         struct rt6_info *rt = (struct rt6_info *) dst;
1301
1302         if (rt) {
1303                 if (rt->rt6i_flags & RTF_CACHE) {
1304                         if (rt6_check_expired(rt)) {
1305                                 ip6_del_rt(rt);
1306                                 dst = NULL;
1307                         }
1308                 } else {
1309                         dst_release(dst);
1310                         dst = NULL;
1311                 }
1312         }
1313         return dst;
1314 }
1315
1316 static void ip6_link_failure(struct sk_buff *skb)
1317 {
1318         struct rt6_info *rt;
1319
1320         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1321
1322         rt = (struct rt6_info *) skb_dst(skb);
1323         if (rt) {
1324                 if (rt->rt6i_flags & RTF_CACHE) {
1325                         dst_hold(&rt->dst);
1326                         ip6_del_rt(rt);
1327                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1328                         rt->rt6i_node->fn_sernum = -1;
1329                 }
1330         }
1331 }
1332
1333 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1334 {
1335         struct net *net = dev_net(rt->dst.dev);
1336
1337         rt->rt6i_flags |= RTF_MODIFIED;
1338         rt->rt6i_pmtu = mtu;
1339         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1340 }
1341
1342 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1343                                  const struct ipv6hdr *iph, u32 mtu)
1344 {
1345         struct rt6_info *rt6 = (struct rt6_info *)dst;
1346
1347         if (rt6->rt6i_flags & RTF_LOCAL)
1348                 return;
1349
1350         dst_confirm(dst);
1351         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1352         if (mtu >= dst_mtu(dst))
1353                 return;
1354
1355         if (rt6->rt6i_flags & RTF_CACHE) {
1356                 rt6_do_update_pmtu(rt6, mtu);
1357         } else {
1358                 const struct in6_addr *daddr, *saddr;
1359                 struct rt6_info *nrt6;
1360
1361                 if (iph) {
1362                         daddr = &iph->daddr;
1363                         saddr = &iph->saddr;
1364                 } else if (sk) {
1365                         daddr = &sk->sk_v6_daddr;
1366                         saddr = &inet6_sk(sk)->saddr;
1367                 } else {
1368                         return;
1369                 }
1370                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1371                 if (nrt6) {
1372                         rt6_do_update_pmtu(nrt6, mtu);
1373
1374                         /* ip6_ins_rt(nrt6) will bump the
1375                          * rt6->rt6i_node->fn_sernum
1376                          * which will fail the next rt6_check() and
1377                          * invalidate the sk->sk_dst_cache.
1378                          */
1379                         ip6_ins_rt(nrt6);
1380                 }
1381         }
1382 }
1383
1384 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1385                                struct sk_buff *skb, u32 mtu)
1386 {
1387         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1388 }
1389
1390 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1391                      int oif, u32 mark)
1392 {
1393         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1394         struct dst_entry *dst;
1395         struct flowi6 fl6;
1396
1397         memset(&fl6, 0, sizeof(fl6));
1398         fl6.flowi6_oif = oif;
1399         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1400         fl6.daddr = iph->daddr;
1401         fl6.saddr = iph->saddr;
1402         fl6.flowlabel = ip6_flowinfo(iph);
1403
1404         dst = ip6_route_output(net, NULL, &fl6);
1405         if (!dst->error)
1406                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1407         dst_release(dst);
1408 }
1409 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1410
1411 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1412 {
1413         ip6_update_pmtu(skb, sock_net(sk), mtu,
1414                         sk->sk_bound_dev_if, sk->sk_mark);
1415 }
1416 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1417
1418 /* Handle redirects */
1419 struct ip6rd_flowi {
1420         struct flowi6 fl6;
1421         struct in6_addr gateway;
1422 };
1423
1424 static struct rt6_info *__ip6_route_redirect(struct net *net,
1425                                              struct fib6_table *table,
1426                                              struct flowi6 *fl6,
1427                                              int flags)
1428 {
1429         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1430         struct rt6_info *rt;
1431         struct fib6_node *fn;
1432
1433         /* Get the "current" route for this destination and
1434          * check if the redirect has come from approriate router.
1435          *
1436          * RFC 4861 specifies that redirects should only be
1437          * accepted if they come from the nexthop to the target.
1438          * Due to the way the routes are chosen, this notion
1439          * is a bit fuzzy and one might need to check all possible
1440          * routes.
1441          */
1442
1443         read_lock_bh(&table->tb6_lock);
1444         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1445 restart:
1446         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1447                 if (rt6_check_expired(rt))
1448                         continue;
1449                 if (rt->dst.error)
1450                         break;
1451                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1452                         continue;
1453                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1454                         continue;
1455                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1456                         continue;
1457                 break;
1458         }
1459
1460         if (!rt)
1461                 rt = net->ipv6.ip6_null_entry;
1462         else if (rt->dst.error) {
1463                 rt = net->ipv6.ip6_null_entry;
1464                 goto out;
1465         }
1466
1467         if (rt == net->ipv6.ip6_null_entry) {
1468                 fn = fib6_backtrack(fn, &fl6->saddr);
1469                 if (fn)
1470                         goto restart;
1471         }
1472
1473 out:
1474         dst_hold(&rt->dst);
1475
1476         read_unlock_bh(&table->tb6_lock);
1477
1478         return rt;
1479 };
1480
1481 static struct dst_entry *ip6_route_redirect(struct net *net,
1482                                         const struct flowi6 *fl6,
1483                                         const struct in6_addr *gateway)
1484 {
1485         int flags = RT6_LOOKUP_F_HAS_SADDR;
1486         struct ip6rd_flowi rdfl;
1487
1488         rdfl.fl6 = *fl6;
1489         rdfl.gateway = *gateway;
1490
1491         return fib6_rule_lookup(net, &rdfl.fl6,
1492                                 flags, __ip6_route_redirect);
1493 }
1494
1495 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1496 {
1497         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1498         struct dst_entry *dst;
1499         struct flowi6 fl6;
1500
1501         memset(&fl6, 0, sizeof(fl6));
1502         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1503         fl6.flowi6_oif = oif;
1504         fl6.flowi6_mark = mark;
1505         fl6.daddr = iph->daddr;
1506         fl6.saddr = iph->saddr;
1507         fl6.flowlabel = ip6_flowinfo(iph);
1508
1509         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1510         rt6_do_redirect(dst, NULL, skb);
1511         dst_release(dst);
1512 }
1513 EXPORT_SYMBOL_GPL(ip6_redirect);
1514
1515 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1516                             u32 mark)
1517 {
1518         const struct ipv6hdr *iph = ipv6_hdr(skb);
1519         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1520         struct dst_entry *dst;
1521         struct flowi6 fl6;
1522
1523         memset(&fl6, 0, sizeof(fl6));
1524         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1525         fl6.flowi6_oif = oif;
1526         fl6.flowi6_mark = mark;
1527         fl6.daddr = msg->dest;
1528         fl6.saddr = iph->daddr;
1529
1530         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1531         rt6_do_redirect(dst, NULL, skb);
1532         dst_release(dst);
1533 }
1534
1535 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1536 {
1537         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1538 }
1539 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1540
1541 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1542 {
1543         struct net_device *dev = dst->dev;
1544         unsigned int mtu = dst_mtu(dst);
1545         struct net *net = dev_net(dev);
1546
1547         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1548
1549         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1550                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1551
1552         /*
1553          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1554          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1555          * IPV6_MAXPLEN is also valid and means: "any MSS,
1556          * rely only on pmtu discovery"
1557          */
1558         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1559                 mtu = IPV6_MAXPLEN;
1560         return mtu;
1561 }
1562
1563 static unsigned int ip6_mtu(const struct dst_entry *dst)
1564 {
1565         const struct rt6_info *rt = (const struct rt6_info *)dst;
1566         unsigned int mtu = rt->rt6i_pmtu;
1567         struct inet6_dev *idev;
1568
1569         if (mtu)
1570                 goto out;
1571
1572         mtu = dst_metric_raw(dst, RTAX_MTU);
1573         if (mtu)
1574                 goto out;
1575
1576         mtu = IPV6_MIN_MTU;
1577
1578         rcu_read_lock();
1579         idev = __in6_dev_get(dst->dev);
1580         if (idev)
1581                 mtu = idev->cnf.mtu6;
1582         rcu_read_unlock();
1583
1584 out:
1585         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1586 }
1587
1588 static struct dst_entry *icmp6_dst_gc_list;
1589 static DEFINE_SPINLOCK(icmp6_dst_lock);
1590
1591 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1592                                   struct flowi6 *fl6)
1593 {
1594         struct dst_entry *dst;
1595         struct rt6_info *rt;
1596         struct inet6_dev *idev = in6_dev_get(dev);
1597         struct net *net = dev_net(dev);
1598
1599         if (unlikely(!idev))
1600                 return ERR_PTR(-ENODEV);
1601
1602         rt = ip6_dst_alloc(net, dev, 0);
1603         if (unlikely(!rt)) {
1604                 in6_dev_put(idev);
1605                 dst = ERR_PTR(-ENOMEM);
1606                 goto out;
1607         }
1608
1609         rt->dst.flags |= DST_HOST;
1610         rt->dst.output  = ip6_output;
1611         atomic_set(&rt->dst.__refcnt, 1);
1612         rt->rt6i_gateway  = fl6->daddr;
1613         rt->rt6i_dst.addr = fl6->daddr;
1614         rt->rt6i_dst.plen = 128;
1615         rt->rt6i_idev     = idev;
1616         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1617
1618         spin_lock_bh(&icmp6_dst_lock);
1619         rt->dst.next = icmp6_dst_gc_list;
1620         icmp6_dst_gc_list = &rt->dst;
1621         spin_unlock_bh(&icmp6_dst_lock);
1622
1623         fib6_force_start_gc(net);
1624
1625         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1626
1627 out:
1628         return dst;
1629 }
1630
1631 int icmp6_dst_gc(void)
1632 {
1633         struct dst_entry *dst, **pprev;
1634         int more = 0;
1635
1636         spin_lock_bh(&icmp6_dst_lock);
1637         pprev = &icmp6_dst_gc_list;
1638
1639         while ((dst = *pprev) != NULL) {
1640                 if (!atomic_read(&dst->__refcnt)) {
1641                         *pprev = dst->next;
1642                         dst_free(dst);
1643                 } else {
1644                         pprev = &dst->next;
1645                         ++more;
1646                 }
1647         }
1648
1649         spin_unlock_bh(&icmp6_dst_lock);
1650
1651         return more;
1652 }
1653
1654 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1655                             void *arg)
1656 {
1657         struct dst_entry *dst, **pprev;
1658
1659         spin_lock_bh(&icmp6_dst_lock);
1660         pprev = &icmp6_dst_gc_list;
1661         while ((dst = *pprev) != NULL) {
1662                 struct rt6_info *rt = (struct rt6_info *) dst;
1663                 if (func(rt, arg)) {
1664                         *pprev = dst->next;
1665                         dst_free(dst);
1666                 } else {
1667                         pprev = &dst->next;
1668                 }
1669         }
1670         spin_unlock_bh(&icmp6_dst_lock);
1671 }
1672
1673 static int ip6_dst_gc(struct dst_ops *ops)
1674 {
1675         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1676         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1677         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1678         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1679         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1680         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1681         int entries;
1682
1683         entries = dst_entries_get_fast(ops);
1684         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1685             entries <= rt_max_size)
1686                 goto out;
1687
1688         net->ipv6.ip6_rt_gc_expire++;
1689         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1690         entries = dst_entries_get_slow(ops);
1691         if (entries < ops->gc_thresh)
1692                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1693 out:
1694         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1695         return entries > rt_max_size;
1696 }
1697
1698 static int ip6_convert_metrics(struct mx6_config *mxc,
1699                                const struct fib6_config *cfg)
1700 {
1701         bool ecn_ca = false;
1702         struct nlattr *nla;
1703         int remaining;
1704         u32 *mp;
1705
1706         if (!cfg->fc_mx)
1707                 return 0;
1708
1709         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1710         if (unlikely(!mp))
1711                 return -ENOMEM;
1712
1713         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1714                 int type = nla_type(nla);
1715                 u32 val;
1716
1717                 if (!type)
1718                         continue;
1719                 if (unlikely(type > RTAX_MAX))
1720                         goto err;
1721
1722                 if (type == RTAX_CC_ALGO) {
1723                         char tmp[TCP_CA_NAME_MAX];
1724
1725                         nla_strlcpy(tmp, nla, sizeof(tmp));
1726                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1727                         if (val == TCP_CA_UNSPEC)
1728                                 goto err;
1729                 } else {
1730                         val = nla_get_u32(nla);
1731                 }
1732                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1733                         goto err;
1734
1735                 mp[type - 1] = val;
1736                 __set_bit(type - 1, mxc->mx_valid);
1737         }
1738
1739         if (ecn_ca) {
1740                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1741                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1742         }
1743
1744         mxc->mx = mp;
1745         return 0;
1746  err:
1747         kfree(mp);
1748         return -EINVAL;
1749 }
1750
1751 int ip6_route_info_create(struct fib6_config *cfg, struct rt6_info **rt_ret)
1752 {
1753         int err;
1754         struct net *net = cfg->fc_nlinfo.nl_net;
1755         struct rt6_info *rt = NULL;
1756         struct net_device *dev = NULL;
1757         struct inet6_dev *idev = NULL;
1758         struct fib6_table *table;
1759         int addr_type;
1760
1761         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1762                 return -EINVAL;
1763 #ifndef CONFIG_IPV6_SUBTREES
1764         if (cfg->fc_src_len)
1765                 return -EINVAL;
1766 #endif
1767         if (cfg->fc_ifindex) {
1768                 err = -ENODEV;
1769                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1770                 if (!dev)
1771                         goto out;
1772                 idev = in6_dev_get(dev);
1773                 if (!idev)
1774                         goto out;
1775         }
1776
1777         if (cfg->fc_metric == 0)
1778                 cfg->fc_metric = IP6_RT_PRIO_USER;
1779
1780         err = -ENOBUFS;
1781         if (cfg->fc_nlinfo.nlh &&
1782             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1783                 table = fib6_get_table(net, cfg->fc_table);
1784                 if (!table) {
1785                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1786                         table = fib6_new_table(net, cfg->fc_table);
1787                 }
1788         } else {
1789                 table = fib6_new_table(net, cfg->fc_table);
1790         }
1791
1792         if (!table)
1793                 goto out;
1794
1795         rt = ip6_dst_alloc(net, NULL,
1796                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1797
1798         if (!rt) {
1799                 err = -ENOMEM;
1800                 goto out;
1801         }
1802
1803         if (cfg->fc_flags & RTF_EXPIRES)
1804                 rt6_set_expires(rt, jiffies +
1805                                 clock_t_to_jiffies(cfg->fc_expires));
1806         else
1807                 rt6_clean_expires(rt);
1808
1809         if (cfg->fc_protocol == RTPROT_UNSPEC)
1810                 cfg->fc_protocol = RTPROT_BOOT;
1811         rt->rt6i_protocol = cfg->fc_protocol;
1812
1813         addr_type = ipv6_addr_type(&cfg->fc_dst);
1814
1815         if (addr_type & IPV6_ADDR_MULTICAST)
1816                 rt->dst.input = ip6_mc_input;
1817         else if (cfg->fc_flags & RTF_LOCAL)
1818                 rt->dst.input = ip6_input;
1819         else
1820                 rt->dst.input = ip6_forward;
1821
1822         rt->dst.output = ip6_output;
1823
1824         if (cfg->fc_encap) {
1825                 struct lwtunnel_state *lwtstate;
1826
1827                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1828                                            cfg->fc_encap, AF_INET6, cfg,
1829                                            &lwtstate);
1830                 if (err)
1831                         goto out;
1832                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1833                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1834                         rt->dst.lwtstate->orig_output = rt->dst.output;
1835                         rt->dst.output = lwtunnel_output;
1836                 }
1837                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1838                         rt->dst.lwtstate->orig_input = rt->dst.input;
1839                         rt->dst.input = lwtunnel_input;
1840                 }
1841         }
1842
1843         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1844         rt->rt6i_dst.plen = cfg->fc_dst_len;
1845         if (rt->rt6i_dst.plen == 128)
1846                 rt->dst.flags |= DST_HOST;
1847
1848 #ifdef CONFIG_IPV6_SUBTREES
1849         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1850         rt->rt6i_src.plen = cfg->fc_src_len;
1851 #endif
1852
1853         rt->rt6i_metric = cfg->fc_metric;
1854
1855         /* We cannot add true routes via loopback here,
1856            they would result in kernel looping; promote them to reject routes
1857          */
1858         if ((cfg->fc_flags & RTF_REJECT) ||
1859             (dev && (dev->flags & IFF_LOOPBACK) &&
1860              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1861              !(cfg->fc_flags & RTF_LOCAL))) {
1862                 /* hold loopback dev/idev if we haven't done so. */
1863                 if (dev != net->loopback_dev) {
1864                         if (dev) {
1865                                 dev_put(dev);
1866                                 in6_dev_put(idev);
1867                         }
1868                         dev = net->loopback_dev;
1869                         dev_hold(dev);
1870                         idev = in6_dev_get(dev);
1871                         if (!idev) {
1872                                 err = -ENODEV;
1873                                 goto out;
1874                         }
1875                 }
1876                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1877                 switch (cfg->fc_type) {
1878                 case RTN_BLACKHOLE:
1879                         rt->dst.error = -EINVAL;
1880                         rt->dst.output = dst_discard_sk;
1881                         rt->dst.input = dst_discard;
1882                         break;
1883                 case RTN_PROHIBIT:
1884                         rt->dst.error = -EACCES;
1885                         rt->dst.output = ip6_pkt_prohibit_out;
1886                         rt->dst.input = ip6_pkt_prohibit;
1887                         break;
1888                 case RTN_THROW:
1889                 case RTN_UNREACHABLE:
1890                 default:
1891                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1892                                         : (cfg->fc_type == RTN_UNREACHABLE)
1893                                         ? -EHOSTUNREACH : -ENETUNREACH;
1894                         rt->dst.output = ip6_pkt_discard_out;
1895                         rt->dst.input = ip6_pkt_discard;
1896                         break;
1897                 }
1898                 goto install_route;
1899         }
1900
1901         if (cfg->fc_flags & RTF_GATEWAY) {
1902                 const struct in6_addr *gw_addr;
1903                 int gwa_type;
1904
1905                 gw_addr = &cfg->fc_gateway;
1906                 gwa_type = ipv6_addr_type(gw_addr);
1907
1908                 /* if gw_addr is local we will fail to detect this in case
1909                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1910                  * will return already-added prefix route via interface that
1911                  * prefix route was assigned to, which might be non-loopback.
1912                  */
1913                 err = -EINVAL;
1914                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1915                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1916                                             dev : NULL, 0, 0))
1917                         goto out;
1918
1919                 rt->rt6i_gateway = *gw_addr;
1920
1921                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1922                         struct rt6_info *grt;
1923
1924                         /* IPv6 strictly inhibits using not link-local
1925                            addresses as nexthop address.
1926                            Otherwise, router will not able to send redirects.
1927                            It is very good, but in some (rare!) circumstances
1928                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1929                            some exceptions. --ANK
1930                          */
1931                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1932                                 goto out;
1933
1934                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1935
1936                         err = -EHOSTUNREACH;
1937                         if (!grt)
1938                                 goto out;
1939                         if (dev) {
1940                                 if (dev != grt->dst.dev) {
1941                                         ip6_rt_put(grt);
1942                                         goto out;
1943                                 }
1944                         } else {
1945                                 dev = grt->dst.dev;
1946                                 idev = grt->rt6i_idev;
1947                                 dev_hold(dev);
1948                                 in6_dev_hold(grt->rt6i_idev);
1949                         }
1950                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1951                                 err = 0;
1952                         ip6_rt_put(grt);
1953
1954                         if (err)
1955                                 goto out;
1956                 }
1957                 err = -EINVAL;
1958                 if (!dev || (dev->flags & IFF_LOOPBACK))
1959                         goto out;
1960         }
1961
1962         err = -ENODEV;
1963         if (!dev)
1964                 goto out;
1965
1966         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1967                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1968                         err = -EINVAL;
1969                         goto out;
1970                 }
1971                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1972                 rt->rt6i_prefsrc.plen = 128;
1973         } else
1974                 rt->rt6i_prefsrc.plen = 0;
1975
1976         rt->rt6i_flags = cfg->fc_flags;
1977
1978 install_route:
1979         rt->dst.dev = dev;
1980         rt->rt6i_idev = idev;
1981         rt->rt6i_table = table;
1982
1983         cfg->fc_nlinfo.nl_net = dev_net(dev);
1984
1985         *rt_ret = rt;
1986
1987         return 0;
1988 out:
1989         if (dev)
1990                 dev_put(dev);
1991         if (idev)
1992                 in6_dev_put(idev);
1993         if (rt)
1994                 dst_free(&rt->dst);
1995
1996         *rt_ret = NULL;
1997
1998         return err;
1999 }
2000
2001 int ip6_route_add(struct fib6_config *cfg)
2002 {
2003         struct mx6_config mxc = { .mx = NULL, };
2004         struct rt6_info *rt = NULL;
2005         int err;
2006
2007         err = ip6_route_info_create(cfg, &rt);
2008         if (err)
2009                 goto out;
2010
2011         err = ip6_convert_metrics(&mxc, cfg);
2012         if (err)
2013                 goto out;
2014
2015         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2016
2017         kfree(mxc.mx);
2018
2019         return err;
2020 out:
2021         if (rt)
2022                 dst_free(&rt->dst);
2023
2024         return err;
2025 }
2026
2027 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2028 {
2029         int err;
2030         struct fib6_table *table;
2031         struct net *net = dev_net(rt->dst.dev);
2032
2033         if (rt == net->ipv6.ip6_null_entry ||
2034             rt->dst.flags & DST_NOCACHE) {
2035                 err = -ENOENT;
2036                 goto out;
2037         }
2038
2039         table = rt->rt6i_table;
2040         write_lock_bh(&table->tb6_lock);
2041         err = fib6_del(rt, info);
2042         write_unlock_bh(&table->tb6_lock);
2043
2044 out:
2045         ip6_rt_put(rt);
2046         return err;
2047 }
2048
2049 int ip6_del_rt(struct rt6_info *rt)
2050 {
2051         struct nl_info info = {
2052                 .nl_net = dev_net(rt->dst.dev),
2053         };
2054         return __ip6_del_rt(rt, &info);
2055 }
2056
2057 static int ip6_route_del(struct fib6_config *cfg)
2058 {
2059         struct fib6_table *table;
2060         struct fib6_node *fn;
2061         struct rt6_info *rt;
2062         int err = -ESRCH;
2063
2064         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2065         if (!table)
2066                 return err;
2067
2068         read_lock_bh(&table->tb6_lock);
2069
2070         fn = fib6_locate(&table->tb6_root,
2071                          &cfg->fc_dst, cfg->fc_dst_len,
2072                          &cfg->fc_src, cfg->fc_src_len);
2073
2074         if (fn) {
2075                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2076                         if ((rt->rt6i_flags & RTF_CACHE) &&
2077                             !(cfg->fc_flags & RTF_CACHE))
2078                                 continue;
2079                         if (cfg->fc_ifindex &&
2080                             (!rt->dst.dev ||
2081                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2082                                 continue;
2083                         if (cfg->fc_flags & RTF_GATEWAY &&
2084                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2085                                 continue;
2086                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2087                                 continue;
2088                         dst_hold(&rt->dst);
2089                         read_unlock_bh(&table->tb6_lock);
2090
2091                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2092                 }
2093         }
2094         read_unlock_bh(&table->tb6_lock);
2095
2096         return err;
2097 }
2098
2099 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2100 {
2101         struct net *net = dev_net(skb->dev);
2102         struct netevent_redirect netevent;
2103         struct rt6_info *rt, *nrt = NULL;
2104         struct ndisc_options ndopts;
2105         struct inet6_dev *in6_dev;
2106         struct neighbour *neigh;
2107         struct rd_msg *msg;
2108         int optlen, on_link;
2109         u8 *lladdr;
2110
2111         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2112         optlen -= sizeof(*msg);
2113
2114         if (optlen < 0) {
2115                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2116                 return;
2117         }
2118
2119         msg = (struct rd_msg *)icmp6_hdr(skb);
2120
2121         if (ipv6_addr_is_multicast(&msg->dest)) {
2122                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2123                 return;
2124         }
2125
2126         on_link = 0;
2127         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2128                 on_link = 1;
2129         } else if (ipv6_addr_type(&msg->target) !=
2130                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2131                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2132                 return;
2133         }
2134
2135         in6_dev = __in6_dev_get(skb->dev);
2136         if (!in6_dev)
2137                 return;
2138         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2139                 return;
2140
2141         /* RFC2461 8.1:
2142          *      The IP source address of the Redirect MUST be the same as the current
2143          *      first-hop router for the specified ICMP Destination Address.
2144          */
2145
2146         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2147                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2148                 return;
2149         }
2150
2151         lladdr = NULL;
2152         if (ndopts.nd_opts_tgt_lladdr) {
2153                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2154                                              skb->dev);
2155                 if (!lladdr) {
2156                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2157                         return;
2158                 }
2159         }
2160
2161         rt = (struct rt6_info *) dst;
2162         if (rt == net->ipv6.ip6_null_entry) {
2163                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2164                 return;
2165         }
2166
2167         /* Redirect received -> path was valid.
2168          * Look, redirects are sent only in response to data packets,
2169          * so that this nexthop apparently is reachable. --ANK
2170          */
2171         dst_confirm(&rt->dst);
2172
2173         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2174         if (!neigh)
2175                 return;
2176
2177         /*
2178          *      We have finally decided to accept it.
2179          */
2180
2181         neigh_update(neigh, lladdr, NUD_STALE,
2182                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2183                      NEIGH_UPDATE_F_OVERRIDE|
2184                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2185                                      NEIGH_UPDATE_F_ISROUTER))
2186                      );
2187
2188         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2189         if (!nrt)
2190                 goto out;
2191
2192         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2193         if (on_link)
2194                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2195
2196         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2197
2198         if (ip6_ins_rt(nrt))
2199                 goto out;
2200
2201         netevent.old = &rt->dst;
2202         netevent.new = &nrt->dst;
2203         netevent.daddr = &msg->dest;
2204         netevent.neigh = neigh;
2205         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2206
2207         if (rt->rt6i_flags & RTF_CACHE) {
2208                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2209                 ip6_del_rt(rt);
2210         }
2211
2212 out:
2213         neigh_release(neigh);
2214 }
2215
2216 /*
2217  *      Misc support functions
2218  */
2219
2220 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2221 {
2222         BUG_ON(from->dst.from);
2223
2224         rt->rt6i_flags &= ~RTF_EXPIRES;
2225         dst_hold(&from->dst);
2226         rt->dst.from = &from->dst;
2227         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2228 }
2229
2230 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2231 {
2232         rt->dst.input = ort->dst.input;
2233         rt->dst.output = ort->dst.output;
2234         rt->rt6i_dst = ort->rt6i_dst;
2235         rt->dst.error = ort->dst.error;
2236         rt->rt6i_idev = ort->rt6i_idev;
2237         if (rt->rt6i_idev)
2238                 in6_dev_hold(rt->rt6i_idev);
2239         rt->dst.lastuse = jiffies;
2240         rt->rt6i_gateway = ort->rt6i_gateway;
2241         rt->rt6i_flags = ort->rt6i_flags;
2242         rt6_set_from(rt, ort);
2243         rt->rt6i_metric = ort->rt6i_metric;
2244 #ifdef CONFIG_IPV6_SUBTREES
2245         rt->rt6i_src = ort->rt6i_src;
2246 #endif
2247         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2248         rt->rt6i_table = ort->rt6i_table;
2249         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2250 }
2251
2252 #ifdef CONFIG_IPV6_ROUTE_INFO
2253 static struct rt6_info *rt6_get_route_info(struct net *net,
2254                                            const struct in6_addr *prefix, int prefixlen,
2255                                            const struct in6_addr *gwaddr, int ifindex)
2256 {
2257         struct fib6_node *fn;
2258         struct rt6_info *rt = NULL;
2259         struct fib6_table *table;
2260
2261         table = fib6_get_table(net, RT6_TABLE_INFO);
2262         if (!table)
2263                 return NULL;
2264
2265         read_lock_bh(&table->tb6_lock);
2266         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2267         if (!fn)
2268                 goto out;
2269
2270         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2271                 if (rt->dst.dev->ifindex != ifindex)
2272                         continue;
2273                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2274                         continue;
2275                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2276                         continue;
2277                 dst_hold(&rt->dst);
2278                 break;
2279         }
2280 out:
2281         read_unlock_bh(&table->tb6_lock);
2282         return rt;
2283 }
2284
2285 static struct rt6_info *rt6_add_route_info(struct net *net,
2286                                            const struct in6_addr *prefix, int prefixlen,
2287                                            const struct in6_addr *gwaddr, int ifindex,
2288                                            unsigned int pref)
2289 {
2290         struct fib6_config cfg = {
2291                 .fc_table       = RT6_TABLE_INFO,
2292                 .fc_metric      = IP6_RT_PRIO_USER,
2293                 .fc_ifindex     = ifindex,
2294                 .fc_dst_len     = prefixlen,
2295                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2296                                   RTF_UP | RTF_PREF(pref),
2297                 .fc_nlinfo.portid = 0,
2298                 .fc_nlinfo.nlh = NULL,
2299                 .fc_nlinfo.nl_net = net,
2300         };
2301
2302         cfg.fc_dst = *prefix;
2303         cfg.fc_gateway = *gwaddr;
2304
2305         /* We should treat it as a default route if prefix length is 0. */
2306         if (!prefixlen)
2307                 cfg.fc_flags |= RTF_DEFAULT;
2308
2309         ip6_route_add(&cfg);
2310
2311         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2312 }
2313 #endif
2314
2315 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2316 {
2317         struct rt6_info *rt;
2318         struct fib6_table *table;
2319
2320         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2321         if (!table)
2322                 return NULL;
2323
2324         read_lock_bh(&table->tb6_lock);
2325         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2326                 if (dev == rt->dst.dev &&
2327                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2328                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2329                         break;
2330         }
2331         if (rt)
2332                 dst_hold(&rt->dst);
2333         read_unlock_bh(&table->tb6_lock);
2334         return rt;
2335 }
2336
2337 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2338                                      struct net_device *dev,
2339                                      unsigned int pref)
2340 {
2341         struct fib6_config cfg = {
2342                 .fc_table       = RT6_TABLE_DFLT,
2343                 .fc_metric      = IP6_RT_PRIO_USER,
2344                 .fc_ifindex     = dev->ifindex,
2345                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2346                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2347                 .fc_nlinfo.portid = 0,
2348                 .fc_nlinfo.nlh = NULL,
2349                 .fc_nlinfo.nl_net = dev_net(dev),
2350         };
2351
2352         cfg.fc_gateway = *gwaddr;
2353
2354         ip6_route_add(&cfg);
2355
2356         return rt6_get_dflt_router(gwaddr, dev);
2357 }
2358
2359 void rt6_purge_dflt_routers(struct net *net)
2360 {
2361         struct rt6_info *rt;
2362         struct fib6_table *table;
2363
2364         /* NOTE: Keep consistent with rt6_get_dflt_router */
2365         table = fib6_get_table(net, RT6_TABLE_DFLT);
2366         if (!table)
2367                 return;
2368
2369 restart:
2370         read_lock_bh(&table->tb6_lock);
2371         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2372                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2373                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2374                         dst_hold(&rt->dst);
2375                         read_unlock_bh(&table->tb6_lock);
2376                         ip6_del_rt(rt);
2377                         goto restart;
2378                 }
2379         }
2380         read_unlock_bh(&table->tb6_lock);
2381 }
2382
2383 static void rtmsg_to_fib6_config(struct net *net,
2384                                  struct in6_rtmsg *rtmsg,
2385                                  struct fib6_config *cfg)
2386 {
2387         memset(cfg, 0, sizeof(*cfg));
2388
2389         cfg->fc_table = RT6_TABLE_MAIN;
2390         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2391         cfg->fc_metric = rtmsg->rtmsg_metric;
2392         cfg->fc_expires = rtmsg->rtmsg_info;
2393         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2394         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2395         cfg->fc_flags = rtmsg->rtmsg_flags;
2396
2397         cfg->fc_nlinfo.nl_net = net;
2398
2399         cfg->fc_dst = rtmsg->rtmsg_dst;
2400         cfg->fc_src = rtmsg->rtmsg_src;
2401         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2402 }
2403
2404 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2405 {
2406         struct fib6_config cfg;
2407         struct in6_rtmsg rtmsg;
2408         int err;
2409
2410         switch (cmd) {
2411         case SIOCADDRT:         /* Add a route */
2412         case SIOCDELRT:         /* Delete a route */
2413                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2414                         return -EPERM;
2415                 err = copy_from_user(&rtmsg, arg,
2416                                      sizeof(struct in6_rtmsg));
2417                 if (err)
2418                         return -EFAULT;
2419
2420                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2421
2422                 rtnl_lock();
2423                 switch (cmd) {
2424                 case SIOCADDRT:
2425                         err = ip6_route_add(&cfg);
2426                         break;
2427                 case SIOCDELRT:
2428                         err = ip6_route_del(&cfg);
2429                         break;
2430                 default:
2431                         err = -EINVAL;
2432                 }
2433                 rtnl_unlock();
2434
2435                 return err;
2436         }
2437
2438         return -EINVAL;
2439 }
2440
2441 /*
2442  *      Drop the packet on the floor
2443  */
2444
2445 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2446 {
2447         int type;
2448         struct dst_entry *dst = skb_dst(skb);
2449         switch (ipstats_mib_noroutes) {
2450         case IPSTATS_MIB_INNOROUTES:
2451                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2452                 if (type == IPV6_ADDR_ANY) {
2453                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2454                                       IPSTATS_MIB_INADDRERRORS);
2455                         break;
2456                 }
2457                 /* FALLTHROUGH */
2458         case IPSTATS_MIB_OUTNOROUTES:
2459                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2460                               ipstats_mib_noroutes);
2461                 break;
2462         }
2463         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2464         kfree_skb(skb);
2465         return 0;
2466 }
2467
2468 static int ip6_pkt_discard(struct sk_buff *skb)
2469 {
2470         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2471 }
2472
2473 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2474 {
2475         skb->dev = skb_dst(skb)->dev;
2476         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2477 }
2478
2479 static int ip6_pkt_prohibit(struct sk_buff *skb)
2480 {
2481         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2482 }
2483
2484 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2485 {
2486         skb->dev = skb_dst(skb)->dev;
2487         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2488 }
2489
2490 /*
2491  *      Allocate a dst for local (unicast / anycast) address.
2492  */
2493
2494 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2495                                     const struct in6_addr *addr,
2496                                     bool anycast)
2497 {
2498         struct net *net = dev_net(idev->dev);
2499         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2500                                             DST_NOCOUNT);
2501         if (!rt)
2502                 return ERR_PTR(-ENOMEM);
2503
2504         in6_dev_hold(idev);
2505
2506         rt->dst.flags |= DST_HOST;
2507         rt->dst.input = ip6_input;
2508         rt->dst.output = ip6_output;
2509         rt->rt6i_idev = idev;
2510
2511         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2512         if (anycast)
2513                 rt->rt6i_flags |= RTF_ANYCAST;
2514         else
2515                 rt->rt6i_flags |= RTF_LOCAL;
2516
2517         rt->rt6i_gateway  = *addr;
2518         rt->rt6i_dst.addr = *addr;
2519         rt->rt6i_dst.plen = 128;
2520         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2521         rt->dst.flags |= DST_NOCACHE;
2522
2523         atomic_set(&rt->dst.__refcnt, 1);
2524
2525         return rt;
2526 }
2527
2528 int ip6_route_get_saddr(struct net *net,
2529                         struct rt6_info *rt,
2530                         const struct in6_addr *daddr,
2531                         unsigned int prefs,
2532                         struct in6_addr *saddr)
2533 {
2534         struct inet6_dev *idev =
2535                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2536         int err = 0;
2537         if (rt && rt->rt6i_prefsrc.plen)
2538                 *saddr = rt->rt6i_prefsrc.addr;
2539         else
2540                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2541                                          daddr, prefs, saddr);
2542         return err;
2543 }
2544
2545 /* remove deleted ip from prefsrc entries */
2546 struct arg_dev_net_ip {
2547         struct net_device *dev;
2548         struct net *net;
2549         struct in6_addr *addr;
2550 };
2551
2552 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2553 {
2554         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2555         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2556         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2557
2558         if (((void *)rt->dst.dev == dev || !dev) &&
2559             rt != net->ipv6.ip6_null_entry &&
2560             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2561                 /* remove prefsrc entry */
2562                 rt->rt6i_prefsrc.plen = 0;
2563         }
2564         return 0;
2565 }
2566
2567 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2568 {
2569         struct net *net = dev_net(ifp->idev->dev);
2570         struct arg_dev_net_ip adni = {
2571                 .dev = ifp->idev->dev,
2572                 .net = net,
2573                 .addr = &ifp->addr,
2574         };
2575         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2576 }
2577
2578 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2579 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2580
2581 /* Remove routers and update dst entries when gateway turn into host. */
2582 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2583 {
2584         struct in6_addr *gateway = (struct in6_addr *)arg;
2585
2586         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2587              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2588              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2589                 return -1;
2590         }
2591         return 0;
2592 }
2593
2594 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2595 {
2596         fib6_clean_all(net, fib6_clean_tohost, gateway);
2597 }
2598
2599 struct arg_dev_net {
2600         struct net_device *dev;
2601         struct net *net;
2602 };
2603
2604 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2605 {
2606         const struct arg_dev_net *adn = arg;
2607         const struct net_device *dev = adn->dev;
2608
2609         if ((rt->dst.dev == dev || !dev) &&
2610             rt != adn->net->ipv6.ip6_null_entry)
2611                 return -1;
2612
2613         return 0;
2614 }
2615
2616 void rt6_ifdown(struct net *net, struct net_device *dev)
2617 {
2618         struct arg_dev_net adn = {
2619                 .dev = dev,
2620                 .net = net,
2621         };
2622
2623         fib6_clean_all(net, fib6_ifdown, &adn);
2624         icmp6_clean_all(fib6_ifdown, &adn);
2625         rt6_uncached_list_flush_dev(net, dev);
2626 }
2627
2628 struct rt6_mtu_change_arg {
2629         struct net_device *dev;
2630         unsigned int mtu;
2631 };
2632
2633 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2634 {
2635         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2636         struct inet6_dev *idev;
2637
2638         /* In IPv6 pmtu discovery is not optional,
2639            so that RTAX_MTU lock cannot disable it.
2640            We still use this lock to block changes
2641            caused by addrconf/ndisc.
2642         */
2643
2644         idev = __in6_dev_get(arg->dev);
2645         if (!idev)
2646                 return 0;
2647
2648         /* For administrative MTU increase, there is no way to discover
2649            IPv6 PMTU increase, so PMTU increase should be updated here.
2650            Since RFC 1981 doesn't include administrative MTU increase
2651            update PMTU increase is a MUST. (i.e. jumbo frame)
2652          */
2653         /*
2654            If new MTU is less than route PMTU, this new MTU will be the
2655            lowest MTU in the path, update the route PMTU to reflect PMTU
2656            decreases; if new MTU is greater than route PMTU, and the
2657            old MTU is the lowest MTU in the path, update the route PMTU
2658            to reflect the increase. In this case if the other nodes' MTU
2659            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2660            PMTU discouvery.
2661          */
2662         if (rt->dst.dev == arg->dev &&
2663             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2664                 if (rt->rt6i_flags & RTF_CACHE) {
2665                         /* For RTF_CACHE with rt6i_pmtu == 0
2666                          * (i.e. a redirected route),
2667                          * the metrics of its rt->dst.from has already
2668                          * been updated.
2669                          */
2670                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2671                                 rt->rt6i_pmtu = arg->mtu;
2672                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2673                            (dst_mtu(&rt->dst) < arg->mtu &&
2674                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2675                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2676                 }
2677         }
2678         return 0;
2679 }
2680
2681 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2682 {
2683         struct rt6_mtu_change_arg arg = {
2684                 .dev = dev,
2685                 .mtu = mtu,
2686         };
2687
2688         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2689 }
2690
2691 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2692         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2693         [RTA_OIF]               = { .type = NLA_U32 },
2694         [RTA_IIF]               = { .type = NLA_U32 },
2695         [RTA_PRIORITY]          = { .type = NLA_U32 },
2696         [RTA_METRICS]           = { .type = NLA_NESTED },
2697         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2698         [RTA_PREF]              = { .type = NLA_U8 },
2699         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2700         [RTA_ENCAP]             = { .type = NLA_NESTED },
2701 };
2702
2703 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2704                               struct fib6_config *cfg)
2705 {
2706         struct rtmsg *rtm;
2707         struct nlattr *tb[RTA_MAX+1];
2708         unsigned int pref;
2709         int err;
2710
2711         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2712         if (err < 0)
2713                 goto errout;
2714
2715         err = -EINVAL;
2716         rtm = nlmsg_data(nlh);
2717         memset(cfg, 0, sizeof(*cfg));
2718
2719         cfg->fc_table = rtm->rtm_table;
2720         cfg->fc_dst_len = rtm->rtm_dst_len;
2721         cfg->fc_src_len = rtm->rtm_src_len;
2722         cfg->fc_flags = RTF_UP;
2723         cfg->fc_protocol = rtm->rtm_protocol;
2724         cfg->fc_type = rtm->rtm_type;
2725
2726         if (rtm->rtm_type == RTN_UNREACHABLE ||
2727             rtm->rtm_type == RTN_BLACKHOLE ||
2728             rtm->rtm_type == RTN_PROHIBIT ||
2729             rtm->rtm_type == RTN_THROW)
2730                 cfg->fc_flags |= RTF_REJECT;
2731
2732         if (rtm->rtm_type == RTN_LOCAL)
2733                 cfg->fc_flags |= RTF_LOCAL;
2734
2735         if (rtm->rtm_flags & RTM_F_CLONED)
2736                 cfg->fc_flags |= RTF_CACHE;
2737
2738         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2739         cfg->fc_nlinfo.nlh = nlh;
2740         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2741
2742         if (tb[RTA_GATEWAY]) {
2743                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2744                 cfg->fc_flags |= RTF_GATEWAY;
2745         }
2746
2747         if (tb[RTA_DST]) {
2748                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2749
2750                 if (nla_len(tb[RTA_DST]) < plen)
2751                         goto errout;
2752
2753                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2754         }
2755
2756         if (tb[RTA_SRC]) {
2757                 int plen = (rtm->rtm_src_len + 7) >> 3;
2758
2759                 if (nla_len(tb[RTA_SRC]) < plen)
2760                         goto errout;
2761
2762                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2763         }
2764
2765         if (tb[RTA_PREFSRC])
2766                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2767
2768         if (tb[RTA_OIF])
2769                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2770
2771         if (tb[RTA_PRIORITY])
2772                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2773
2774         if (tb[RTA_METRICS]) {
2775                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2776                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2777         }
2778
2779         if (tb[RTA_TABLE])
2780                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2781
2782         if (tb[RTA_MULTIPATH]) {
2783                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2784                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2785         }
2786
2787         if (tb[RTA_PREF]) {
2788                 pref = nla_get_u8(tb[RTA_PREF]);
2789                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2790                     pref != ICMPV6_ROUTER_PREF_HIGH)
2791                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2792                 cfg->fc_flags |= RTF_PREF(pref);
2793         }
2794
2795         if (tb[RTA_ENCAP])
2796                 cfg->fc_encap = tb[RTA_ENCAP];
2797
2798         if (tb[RTA_ENCAP_TYPE])
2799                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2800
2801         err = 0;
2802 errout:
2803         return err;
2804 }
2805
2806 struct rt6_nh {
2807         struct rt6_info *rt6_info;
2808         struct fib6_config r_cfg;
2809         struct mx6_config mxc;
2810         struct list_head next;
2811 };
2812
2813 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2814 {
2815         struct rt6_nh *nh;
2816
2817         list_for_each_entry(nh, rt6_nh_list, next) {
2818                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2819                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2820                         nh->r_cfg.fc_ifindex);
2821         }
2822 }
2823
2824 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2825                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2826 {
2827         struct rt6_nh *nh;
2828         struct rt6_info *rtnh;
2829         int err = -EEXIST;
2830
2831         list_for_each_entry(nh, rt6_nh_list, next) {
2832                 /* check if rt6_info already exists */
2833                 rtnh = nh->rt6_info;
2834
2835                 if (rtnh->dst.dev == rt->dst.dev &&
2836                     rtnh->rt6i_idev == rt->rt6i_idev &&
2837                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2838                                     &rt->rt6i_gateway))
2839                         return err;
2840         }
2841
2842         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2843         if (!nh)
2844                 return -ENOMEM;
2845         nh->rt6_info = rt;
2846         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2847         if (err) {
2848                 kfree(nh);
2849                 return err;
2850         }
2851         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2852         list_add_tail(&nh->next, rt6_nh_list);
2853
2854         return 0;
2855 }
2856
2857 static int ip6_route_multipath_add(struct fib6_config *cfg)
2858 {
2859         struct fib6_config r_cfg;
2860         struct rtnexthop *rtnh;
2861         struct rt6_info *rt;
2862         struct rt6_nh *err_nh;
2863         struct rt6_nh *nh, *nh_safe;
2864         int remaining;
2865         int attrlen;
2866         int err = 1;
2867         int nhn = 0;
2868         int replace = (cfg->fc_nlinfo.nlh &&
2869                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2870         LIST_HEAD(rt6_nh_list);
2871
2872         remaining = cfg->fc_mp_len;
2873         rtnh = (struct rtnexthop *)cfg->fc_mp;
2874
2875         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2876          * rt6_info structs per nexthop
2877          */
2878         while (rtnh_ok(rtnh, remaining)) {
2879                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2880                 if (rtnh->rtnh_ifindex)
2881                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2882
2883                 attrlen = rtnh_attrlen(rtnh);
2884                 if (attrlen > 0) {
2885                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2886
2887                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2888                         if (nla) {
2889                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2890                                 r_cfg.fc_flags |= RTF_GATEWAY;
2891                         }
2892                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2893                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2894                         if (nla)
2895                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2896                 }
2897
2898                 err = ip6_route_info_create(&r_cfg, &rt);
2899                 if (err)
2900                         goto cleanup;
2901
2902                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2903                 if (err) {
2904                         dst_free(&rt->dst);
2905                         goto cleanup;
2906                 }
2907
2908                 rtnh = rtnh_next(rtnh, &remaining);
2909         }
2910
2911         err_nh = NULL;
2912         list_for_each_entry(nh, &rt6_nh_list, next) {
2913                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2914                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2915                 nh->rt6_info = NULL;
2916                 if (err) {
2917                         if (replace && nhn)
2918                                 ip6_print_replace_route_err(&rt6_nh_list);
2919                         err_nh = nh;
2920                         goto add_errout;
2921                 }
2922
2923                 /* Because each route is added like a single route we remove
2924                  * these flags after the first nexthop: if there is a collision,
2925                  * we have already failed to add the first nexthop:
2926                  * fib6_add_rt2node() has rejected it; when replacing, old
2927                  * nexthops have been replaced by first new, the rest should
2928                  * be added to it.
2929                  */
2930                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2931                                                      NLM_F_REPLACE);
2932                 nhn++;
2933         }
2934
2935         goto cleanup;
2936
2937 add_errout:
2938         /* Delete routes that were already added */
2939         list_for_each_entry(nh, &rt6_nh_list, next) {
2940                 if (err_nh == nh)
2941                         break;
2942                 ip6_route_del(&nh->r_cfg);
2943         }
2944
2945 cleanup:
2946         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2947                 if (nh->rt6_info)
2948                         dst_free(&nh->rt6_info->dst);
2949                 kfree(nh->mxc.mx);
2950                 list_del(&nh->next);
2951                 kfree(nh);
2952         }
2953
2954         return err;
2955 }
2956
2957 static int ip6_route_multipath_del(struct fib6_config *cfg)
2958 {
2959         struct fib6_config r_cfg;
2960         struct rtnexthop *rtnh;
2961         int remaining;
2962         int attrlen;
2963         int err = 1, last_err = 0;
2964
2965         remaining = cfg->fc_mp_len;
2966         rtnh = (struct rtnexthop *)cfg->fc_mp;
2967
2968         /* Parse a Multipath Entry */
2969         while (rtnh_ok(rtnh, remaining)) {
2970                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2971                 if (rtnh->rtnh_ifindex)
2972                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2973
2974                 attrlen = rtnh_attrlen(rtnh);
2975                 if (attrlen > 0) {
2976                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2977
2978                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2979                         if (nla) {
2980                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2981                                 r_cfg.fc_flags |= RTF_GATEWAY;
2982                         }
2983                 }
2984                 err = ip6_route_del(&r_cfg);
2985                 if (err)
2986                         last_err = err;
2987
2988                 rtnh = rtnh_next(rtnh, &remaining);
2989         }
2990
2991         return last_err;
2992 }
2993
2994 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2995 {
2996         struct fib6_config cfg;
2997         int err;
2998
2999         err = rtm_to_fib6_config(skb, nlh, &cfg);
3000         if (err < 0)
3001                 return err;
3002
3003         if (cfg.fc_mp)
3004                 return ip6_route_multipath_del(&cfg);
3005         else
3006                 return ip6_route_del(&cfg);
3007 }
3008
3009 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3010 {
3011         struct fib6_config cfg;
3012         int err;
3013
3014         err = rtm_to_fib6_config(skb, nlh, &cfg);
3015         if (err < 0)
3016                 return err;
3017
3018         if (cfg.fc_mp)
3019                 return ip6_route_multipath_add(&cfg);
3020         else
3021                 return ip6_route_add(&cfg);
3022 }
3023
3024 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3025 {
3026         return NLMSG_ALIGN(sizeof(struct rtmsg))
3027                + nla_total_size(16) /* RTA_SRC */
3028                + nla_total_size(16) /* RTA_DST */
3029                + nla_total_size(16) /* RTA_GATEWAY */
3030                + nla_total_size(16) /* RTA_PREFSRC */
3031                + nla_total_size(4) /* RTA_TABLE */
3032                + nla_total_size(4) /* RTA_IIF */
3033                + nla_total_size(4) /* RTA_OIF */
3034                + nla_total_size(4) /* RTA_PRIORITY */
3035                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3036                + nla_total_size(sizeof(struct rta_cacheinfo))
3037                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3038                + nla_total_size(1) /* RTA_PREF */
3039                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3040 }
3041
3042 static int rt6_fill_node(struct net *net,
3043                          struct sk_buff *skb, struct rt6_info *rt,
3044                          struct in6_addr *dst, struct in6_addr *src,
3045                          int iif, int type, u32 portid, u32 seq,
3046                          int prefix, int nowait, unsigned int flags)
3047 {
3048         u32 metrics[RTAX_MAX];
3049         struct rtmsg *rtm;
3050         struct nlmsghdr *nlh;
3051         long expires;
3052         u32 table;
3053
3054         if (prefix) {   /* user wants prefix routes only */
3055                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3056                         /* success since this is not a prefix route */
3057                         return 1;
3058                 }
3059         }
3060
3061         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3062         if (!nlh)
3063                 return -EMSGSIZE;
3064
3065         rtm = nlmsg_data(nlh);
3066         rtm->rtm_family = AF_INET6;
3067         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3068         rtm->rtm_src_len = rt->rt6i_src.plen;
3069         rtm->rtm_tos = 0;
3070         if (rt->rt6i_table)
3071                 table = rt->rt6i_table->tb6_id;
3072         else
3073                 table = RT6_TABLE_UNSPEC;
3074         rtm->rtm_table = table;
3075         if (nla_put_u32(skb, RTA_TABLE, table))
3076                 goto nla_put_failure;
3077         if (rt->rt6i_flags & RTF_REJECT) {
3078                 switch (rt->dst.error) {
3079                 case -EINVAL:
3080                         rtm->rtm_type = RTN_BLACKHOLE;
3081                         break;
3082                 case -EACCES:
3083                         rtm->rtm_type = RTN_PROHIBIT;
3084                         break;
3085                 case -EAGAIN:
3086                         rtm->rtm_type = RTN_THROW;
3087                         break;
3088                 default:
3089                         rtm->rtm_type = RTN_UNREACHABLE;
3090                         break;
3091                 }
3092         }
3093         else if (rt->rt6i_flags & RTF_LOCAL)
3094                 rtm->rtm_type = RTN_LOCAL;
3095         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3096                 rtm->rtm_type = RTN_LOCAL;
3097         else
3098                 rtm->rtm_type = RTN_UNICAST;
3099         rtm->rtm_flags = 0;
3100         if (!netif_carrier_ok(rt->dst.dev)) {
3101                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3102                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3103                         rtm->rtm_flags |= RTNH_F_DEAD;
3104         }
3105         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3106         rtm->rtm_protocol = rt->rt6i_protocol;
3107         if (rt->rt6i_flags & RTF_DYNAMIC)
3108                 rtm->rtm_protocol = RTPROT_REDIRECT;
3109         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3110                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3111                         rtm->rtm_protocol = RTPROT_RA;
3112                 else
3113                         rtm->rtm_protocol = RTPROT_KERNEL;
3114         }
3115
3116         if (rt->rt6i_flags & RTF_CACHE)
3117                 rtm->rtm_flags |= RTM_F_CLONED;
3118
3119         if (dst) {
3120                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3121                         goto nla_put_failure;
3122                 rtm->rtm_dst_len = 128;
3123         } else if (rtm->rtm_dst_len)
3124                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3125                         goto nla_put_failure;
3126 #ifdef CONFIG_IPV6_SUBTREES
3127         if (src) {
3128                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3129                         goto nla_put_failure;
3130                 rtm->rtm_src_len = 128;
3131         } else if (rtm->rtm_src_len &&
3132                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3133                 goto nla_put_failure;
3134 #endif
3135         if (iif) {
3136 #ifdef CONFIG_IPV6_MROUTE
3137                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3138                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3139                         if (err <= 0) {
3140                                 if (!nowait) {
3141                                         if (err == 0)
3142                                                 return 0;
3143                                         goto nla_put_failure;
3144                                 } else {
3145                                         if (err == -EMSGSIZE)
3146                                                 goto nla_put_failure;
3147                                 }
3148                         }
3149                 } else
3150 #endif
3151                         if (nla_put_u32(skb, RTA_IIF, iif))
3152                                 goto nla_put_failure;
3153         } else if (dst) {
3154                 struct in6_addr saddr_buf;
3155                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3156                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3157                         goto nla_put_failure;
3158         }
3159
3160         if (rt->rt6i_prefsrc.plen) {
3161                 struct in6_addr saddr_buf;
3162                 saddr_buf = rt->rt6i_prefsrc.addr;
3163                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3164                         goto nla_put_failure;
3165         }
3166
3167         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3168         if (rt->rt6i_pmtu)
3169                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3170         if (rtnetlink_put_metrics(skb, metrics) < 0)
3171                 goto nla_put_failure;
3172
3173         if (rt->rt6i_flags & RTF_GATEWAY) {
3174                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3175                         goto nla_put_failure;
3176         }
3177
3178         if (rt->dst.dev &&
3179             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3180                 goto nla_put_failure;
3181         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3182                 goto nla_put_failure;
3183
3184         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3185
3186         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3187                 goto nla_put_failure;
3188
3189         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3190                 goto nla_put_failure;
3191
3192         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3193
3194         nlmsg_end(skb, nlh);
3195         return 0;
3196
3197 nla_put_failure:
3198         nlmsg_cancel(skb, nlh);
3199         return -EMSGSIZE;
3200 }
3201
3202 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3203 {
3204         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3205         int prefix;
3206
3207         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3208                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3209                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3210         } else
3211                 prefix = 0;
3212
3213         return rt6_fill_node(arg->net,
3214                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3215                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3216                      prefix, 0, NLM_F_MULTI);
3217 }
3218
3219 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3220 {
3221         struct net *net = sock_net(in_skb->sk);
3222         struct nlattr *tb[RTA_MAX+1];
3223         struct rt6_info *rt;
3224         struct sk_buff *skb;
3225         struct rtmsg *rtm;
3226         struct flowi6 fl6;
3227         int err, iif = 0, oif = 0;
3228
3229         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3230         if (err < 0)
3231                 goto errout;
3232
3233         err = -EINVAL;
3234         memset(&fl6, 0, sizeof(fl6));
3235
3236         if (tb[RTA_SRC]) {
3237                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3238                         goto errout;
3239
3240                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3241         }
3242
3243         if (tb[RTA_DST]) {
3244                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3245                         goto errout;
3246
3247                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3248         }
3249
3250         if (tb[RTA_IIF])
3251                 iif = nla_get_u32(tb[RTA_IIF]);
3252
3253         if (tb[RTA_OIF])
3254                 oif = nla_get_u32(tb[RTA_OIF]);
3255
3256         if (tb[RTA_MARK])
3257                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3258
3259         if (iif) {
3260                 struct net_device *dev;
3261                 int flags = 0;
3262
3263                 dev = __dev_get_by_index(net, iif);
3264                 if (!dev) {
3265                         err = -ENODEV;
3266                         goto errout;
3267                 }
3268
3269                 fl6.flowi6_iif = iif;
3270
3271                 if (!ipv6_addr_any(&fl6.saddr))
3272                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3273
3274                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3275                                                                flags);
3276         } else {
3277                 fl6.flowi6_oif = oif;
3278
3279                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3280         }
3281
3282         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3283         if (!skb) {
3284                 ip6_rt_put(rt);
3285                 err = -ENOBUFS;
3286                 goto errout;
3287         }
3288
3289         /* Reserve room for dummy headers, this skb can pass
3290            through good chunk of routing engine.
3291          */
3292         skb_reset_mac_header(skb);
3293         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3294
3295         skb_dst_set(skb, &rt->dst);
3296
3297         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3298                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3299                             nlh->nlmsg_seq, 0, 0, 0);
3300         if (err < 0) {
3301                 kfree_skb(skb);
3302                 goto errout;
3303         }
3304
3305         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3306 errout:
3307         return err;
3308 }
3309
3310 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3311                      unsigned int nlm_flags)
3312 {
3313         struct sk_buff *skb;
3314         struct net *net = info->nl_net;
3315         u32 seq;
3316         int err;
3317
3318         err = -ENOBUFS;
3319         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3320
3321         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3322         if (!skb)
3323                 goto errout;
3324
3325         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3326                                 event, info->portid, seq, 0, 0, nlm_flags);
3327         if (err < 0) {
3328                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3329                 WARN_ON(err == -EMSGSIZE);
3330                 kfree_skb(skb);
3331                 goto errout;
3332         }
3333         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3334                     info->nlh, gfp_any());
3335         return;
3336 errout:
3337         if (err < 0)
3338                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3339 }
3340
3341 static int ip6_route_dev_notify(struct notifier_block *this,
3342                                 unsigned long event, void *ptr)
3343 {
3344         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3345         struct net *net = dev_net(dev);
3346
3347         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3348                 net->ipv6.ip6_null_entry->dst.dev = dev;
3349                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3350 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3351                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3352                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3353                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3354                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3355 #endif
3356         }
3357
3358         return NOTIFY_OK;
3359 }
3360
3361 /*
3362  *      /proc
3363  */
3364
3365 #ifdef CONFIG_PROC_FS
3366
3367 static const struct file_operations ipv6_route_proc_fops = {
3368         .owner          = THIS_MODULE,
3369         .open           = ipv6_route_open,
3370         .read           = seq_read,
3371         .llseek         = seq_lseek,
3372         .release        = seq_release_net,
3373 };
3374
3375 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3376 {
3377         struct net *net = (struct net *)seq->private;
3378         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3379                    net->ipv6.rt6_stats->fib_nodes,
3380                    net->ipv6.rt6_stats->fib_route_nodes,
3381                    net->ipv6.rt6_stats->fib_rt_alloc,
3382                    net->ipv6.rt6_stats->fib_rt_entries,
3383                    net->ipv6.rt6_stats->fib_rt_cache,
3384                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3385                    net->ipv6.rt6_stats->fib_discarded_routes);
3386
3387         return 0;
3388 }
3389
3390 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3391 {
3392         return single_open_net(inode, file, rt6_stats_seq_show);
3393 }
3394
3395 static const struct file_operations rt6_stats_seq_fops = {
3396         .owner   = THIS_MODULE,
3397         .open    = rt6_stats_seq_open,
3398         .read    = seq_read,
3399         .llseek  = seq_lseek,
3400         .release = single_release_net,
3401 };
3402 #endif  /* CONFIG_PROC_FS */
3403
3404 #ifdef CONFIG_SYSCTL
3405
3406 static
3407 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3408                               void __user *buffer, size_t *lenp, loff_t *ppos)
3409 {
3410         struct net *net;
3411         int delay;
3412         if (!write)
3413                 return -EINVAL;
3414
3415         net = (struct net *)ctl->extra1;
3416         delay = net->ipv6.sysctl.flush_delay;
3417         proc_dointvec(ctl, write, buffer, lenp, ppos);
3418         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3419         return 0;
3420 }
3421
3422 struct ctl_table ipv6_route_table_template[] = {
3423         {
3424                 .procname       =       "flush",
3425                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3426                 .maxlen         =       sizeof(int),
3427                 .mode           =       0200,
3428                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3429         },
3430         {
3431                 .procname       =       "gc_thresh",
3432                 .data           =       &ip6_dst_ops_template.gc_thresh,
3433                 .maxlen         =       sizeof(int),
3434                 .mode           =       0644,
3435                 .proc_handler   =       proc_dointvec,
3436         },
3437         {
3438                 .procname       =       "max_size",
3439                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3440                 .maxlen         =       sizeof(int),
3441                 .mode           =       0644,
3442                 .proc_handler   =       proc_dointvec,
3443         },
3444         {
3445                 .procname       =       "gc_min_interval",
3446                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3447                 .maxlen         =       sizeof(int),
3448                 .mode           =       0644,
3449                 .proc_handler   =       proc_dointvec_jiffies,
3450         },
3451         {
3452                 .procname       =       "gc_timeout",
3453                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3454                 .maxlen         =       sizeof(int),
3455                 .mode           =       0644,
3456                 .proc_handler   =       proc_dointvec_jiffies,
3457         },
3458         {
3459                 .procname       =       "gc_interval",
3460                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3461                 .maxlen         =       sizeof(int),
3462                 .mode           =       0644,
3463                 .proc_handler   =       proc_dointvec_jiffies,
3464         },
3465         {
3466                 .procname       =       "gc_elasticity",
3467                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3468                 .maxlen         =       sizeof(int),
3469                 .mode           =       0644,
3470                 .proc_handler   =       proc_dointvec,
3471         },
3472         {
3473                 .procname       =       "mtu_expires",
3474                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3475                 .maxlen         =       sizeof(int),
3476                 .mode           =       0644,
3477                 .proc_handler   =       proc_dointvec_jiffies,
3478         },
3479         {
3480                 .procname       =       "min_adv_mss",
3481                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3482                 .maxlen         =       sizeof(int),
3483                 .mode           =       0644,
3484                 .proc_handler   =       proc_dointvec,
3485         },
3486         {
3487                 .procname       =       "gc_min_interval_ms",
3488                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3489                 .maxlen         =       sizeof(int),
3490                 .mode           =       0644,
3491                 .proc_handler   =       proc_dointvec_ms_jiffies,
3492         },
3493         { }
3494 };
3495
3496 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3497 {
3498         struct ctl_table *table;
3499
3500         table = kmemdup(ipv6_route_table_template,
3501                         sizeof(ipv6_route_table_template),
3502                         GFP_KERNEL);
3503
3504         if (table) {
3505                 table[0].data = &net->ipv6.sysctl.flush_delay;
3506                 table[0].extra1 = net;
3507                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3508                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3509                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3510                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3511                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3512                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3513                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3514                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3515                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3516
3517                 /* Don't export sysctls to unprivileged users */
3518                 if (net->user_ns != &init_user_ns)
3519                         table[0].procname = NULL;
3520         }
3521
3522         return table;
3523 }
3524 #endif
3525
3526 static int __net_init ip6_route_net_init(struct net *net)
3527 {
3528         int ret = -ENOMEM;
3529
3530         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3531                sizeof(net->ipv6.ip6_dst_ops));
3532
3533         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3534                 goto out_ip6_dst_ops;
3535
3536         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3537                                            sizeof(*net->ipv6.ip6_null_entry),
3538                                            GFP_KERNEL);
3539         if (!net->ipv6.ip6_null_entry)
3540                 goto out_ip6_dst_entries;
3541         net->ipv6.ip6_null_entry->dst.path =
3542                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3543         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3544         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3545                          ip6_template_metrics, true);
3546
3547 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3548         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3549                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3550                                                GFP_KERNEL);
3551         if (!net->ipv6.ip6_prohibit_entry)
3552                 goto out_ip6_null_entry;
3553         net->ipv6.ip6_prohibit_entry->dst.path =
3554                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3555         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3556         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3557                          ip6_template_metrics, true);
3558
3559         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3560                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3561                                                GFP_KERNEL);
3562         if (!net->ipv6.ip6_blk_hole_entry)
3563                 goto out_ip6_prohibit_entry;
3564         net->ipv6.ip6_blk_hole_entry->dst.path =
3565                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3566         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3567         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3568                          ip6_template_metrics, true);
3569 #endif
3570
3571         net->ipv6.sysctl.flush_delay = 0;
3572         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3573         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3574         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3575         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3576         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3577         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3578         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3579
3580         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3581
3582         ret = 0;
3583 out:
3584         return ret;
3585
3586 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3587 out_ip6_prohibit_entry:
3588         kfree(net->ipv6.ip6_prohibit_entry);
3589 out_ip6_null_entry:
3590         kfree(net->ipv6.ip6_null_entry);
3591 #endif
3592 out_ip6_dst_entries:
3593         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3594 out_ip6_dst_ops:
3595         goto out;
3596 }
3597
3598 static void __net_exit ip6_route_net_exit(struct net *net)
3599 {
3600         kfree(net->ipv6.ip6_null_entry);
3601 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3602         kfree(net->ipv6.ip6_prohibit_entry);
3603         kfree(net->ipv6.ip6_blk_hole_entry);
3604 #endif
3605         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3606 }
3607
3608 static int __net_init ip6_route_net_init_late(struct net *net)
3609 {
3610 #ifdef CONFIG_PROC_FS
3611         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3612         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3613 #endif
3614         return 0;
3615 }
3616
3617 static void __net_exit ip6_route_net_exit_late(struct net *net)
3618 {
3619 #ifdef CONFIG_PROC_FS
3620         remove_proc_entry("ipv6_route", net->proc_net);
3621         remove_proc_entry("rt6_stats", net->proc_net);
3622 #endif
3623 }
3624
3625 static struct pernet_operations ip6_route_net_ops = {
3626         .init = ip6_route_net_init,
3627         .exit = ip6_route_net_exit,
3628 };
3629
3630 static int __net_init ipv6_inetpeer_init(struct net *net)
3631 {
3632         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3633
3634         if (!bp)
3635                 return -ENOMEM;
3636         inet_peer_base_init(bp);
3637         net->ipv6.peers = bp;
3638         return 0;
3639 }
3640
3641 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3642 {
3643         struct inet_peer_base *bp = net->ipv6.peers;
3644
3645         net->ipv6.peers = NULL;
3646         inetpeer_invalidate_tree(bp);
3647         kfree(bp);
3648 }
3649
3650 static struct pernet_operations ipv6_inetpeer_ops = {
3651         .init   =       ipv6_inetpeer_init,
3652         .exit   =       ipv6_inetpeer_exit,
3653 };
3654
3655 static struct pernet_operations ip6_route_net_late_ops = {
3656         .init = ip6_route_net_init_late,
3657         .exit = ip6_route_net_exit_late,
3658 };
3659
3660 static struct notifier_block ip6_route_dev_notifier = {
3661         .notifier_call = ip6_route_dev_notify,
3662         .priority = 0,
3663 };
3664
3665 int __init ip6_route_init(void)
3666 {
3667         int ret;
3668         int cpu;
3669
3670         ret = -ENOMEM;
3671         ip6_dst_ops_template.kmem_cachep =
3672                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3673                                   SLAB_HWCACHE_ALIGN, NULL);
3674         if (!ip6_dst_ops_template.kmem_cachep)
3675                 goto out;
3676
3677         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3678         if (ret)
3679                 goto out_kmem_cache;
3680
3681         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3682         if (ret)
3683                 goto out_dst_entries;
3684
3685         ret = register_pernet_subsys(&ip6_route_net_ops);
3686         if (ret)
3687                 goto out_register_inetpeer;
3688
3689         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3690
3691         /* Registering of the loopback is done before this portion of code,
3692          * the loopback reference in rt6_info will not be taken, do it
3693          * manually for init_net */
3694         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3695         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3696   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3697         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3698         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3699         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3700         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3701   #endif
3702         ret = fib6_init();
3703         if (ret)
3704                 goto out_register_subsys;
3705
3706         ret = xfrm6_init();
3707         if (ret)
3708                 goto out_fib6_init;
3709
3710         ret = fib6_rules_init();
3711         if (ret)
3712                 goto xfrm6_init;
3713
3714         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3715         if (ret)
3716                 goto fib6_rules_init;
3717
3718         ret = -ENOBUFS;
3719         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3720             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3721             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3722                 goto out_register_late_subsys;
3723
3724         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3725         if (ret)
3726                 goto out_register_late_subsys;
3727
3728         for_each_possible_cpu(cpu) {
3729                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3730
3731                 INIT_LIST_HEAD(&ul->head);
3732                 spin_lock_init(&ul->lock);
3733         }
3734
3735 out:
3736         return ret;
3737
3738 out_register_late_subsys:
3739         unregister_pernet_subsys(&ip6_route_net_late_ops);
3740 fib6_rules_init:
3741         fib6_rules_cleanup();
3742 xfrm6_init:
3743         xfrm6_fini();
3744 out_fib6_init:
3745         fib6_gc_cleanup();
3746 out_register_subsys:
3747         unregister_pernet_subsys(&ip6_route_net_ops);
3748 out_register_inetpeer:
3749         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3750 out_dst_entries:
3751         dst_entries_destroy(&ip6_dst_blackhole_ops);
3752 out_kmem_cache:
3753         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3754         goto out;
3755 }
3756
3757 void ip6_route_cleanup(void)
3758 {
3759         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3760         unregister_pernet_subsys(&ip6_route_net_late_ops);
3761         fib6_rules_cleanup();
3762         xfrm6_fini();
3763         fib6_gc_cleanup();
3764         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3765         unregister_pernet_subsys(&ip6_route_net_ops);
3766         dst_entries_destroy(&ip6_dst_blackhole_ops);
3767         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3768 }