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                 flags |= RT6_LOOKUP_F_IFACE;
1198
1199         if (!ipv6_addr_any(&fl6->saddr))
1200                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1201         else if (sk)
1202                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1203
1204         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1205 }
1206 EXPORT_SYMBOL(ip6_route_output);
1207
1208 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1209 {
1210         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1211         struct dst_entry *new = NULL;
1212
1213         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1214         if (rt) {
1215                 new = &rt->dst;
1216
1217                 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1218
1219                 new->__use = 1;
1220                 new->input = dst_discard;
1221                 new->output = dst_discard_sk;
1222
1223                 if (dst_metrics_read_only(&ort->dst))
1224                         new->_metrics = ort->dst._metrics;
1225                 else
1226                         dst_copy_metrics(new, &ort->dst);
1227                 rt->rt6i_idev = ort->rt6i_idev;
1228                 if (rt->rt6i_idev)
1229                         in6_dev_hold(rt->rt6i_idev);
1230
1231                 rt->rt6i_gateway = ort->rt6i_gateway;
1232                 rt->rt6i_flags = ort->rt6i_flags;
1233                 rt->rt6i_metric = 0;
1234
1235                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1236 #ifdef CONFIG_IPV6_SUBTREES
1237                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1238 #endif
1239
1240                 dst_free(new);
1241         }
1242
1243         dst_release(dst_orig);
1244         return new ? new : ERR_PTR(-ENOMEM);
1245 }
1246
1247 /*
1248  *      Destination cache support functions
1249  */
1250
1251 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1252 {
1253         if (rt->dst.from &&
1254             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1255                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1256 }
1257
1258 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1259 {
1260         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1261                 return NULL;
1262
1263         if (rt6_check_expired(rt))
1264                 return NULL;
1265
1266         return &rt->dst;
1267 }
1268
1269 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1270 {
1271         if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1272             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1273                 return &rt->dst;
1274         else
1275                 return NULL;
1276 }
1277
1278 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1279 {
1280         struct rt6_info *rt;
1281
1282         rt = (struct rt6_info *) dst;
1283
1284         /* All IPV6 dsts are created with ->obsolete set to the value
1285          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1286          * into this function always.
1287          */
1288
1289         rt6_dst_from_metrics_check(rt);
1290
1291         if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1292                 return rt6_dst_from_check(rt, cookie);
1293         else
1294                 return rt6_check(rt, cookie);
1295 }
1296
1297 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1298 {
1299         struct rt6_info *rt = (struct rt6_info *) dst;
1300
1301         if (rt) {
1302                 if (rt->rt6i_flags & RTF_CACHE) {
1303                         if (rt6_check_expired(rt)) {
1304                                 ip6_del_rt(rt);
1305                                 dst = NULL;
1306                         }
1307                 } else {
1308                         dst_release(dst);
1309                         dst = NULL;
1310                 }
1311         }
1312         return dst;
1313 }
1314
1315 static void ip6_link_failure(struct sk_buff *skb)
1316 {
1317         struct rt6_info *rt;
1318
1319         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1320
1321         rt = (struct rt6_info *) skb_dst(skb);
1322         if (rt) {
1323                 if (rt->rt6i_flags & RTF_CACHE) {
1324                         dst_hold(&rt->dst);
1325                         ip6_del_rt(rt);
1326                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1327                         rt->rt6i_node->fn_sernum = -1;
1328                 }
1329         }
1330 }
1331
1332 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1333 {
1334         struct net *net = dev_net(rt->dst.dev);
1335
1336         rt->rt6i_flags |= RTF_MODIFIED;
1337         rt->rt6i_pmtu = mtu;
1338         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1339 }
1340
1341 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1342                                  const struct ipv6hdr *iph, u32 mtu)
1343 {
1344         struct rt6_info *rt6 = (struct rt6_info *)dst;
1345
1346         if (rt6->rt6i_flags & RTF_LOCAL)
1347                 return;
1348
1349         dst_confirm(dst);
1350         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1351         if (mtu >= dst_mtu(dst))
1352                 return;
1353
1354         if (rt6->rt6i_flags & RTF_CACHE) {
1355                 rt6_do_update_pmtu(rt6, mtu);
1356         } else {
1357                 const struct in6_addr *daddr, *saddr;
1358                 struct rt6_info *nrt6;
1359
1360                 if (iph) {
1361                         daddr = &iph->daddr;
1362                         saddr = &iph->saddr;
1363                 } else if (sk) {
1364                         daddr = &sk->sk_v6_daddr;
1365                         saddr = &inet6_sk(sk)->saddr;
1366                 } else {
1367                         return;
1368                 }
1369                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1370                 if (nrt6) {
1371                         rt6_do_update_pmtu(nrt6, mtu);
1372
1373                         /* ip6_ins_rt(nrt6) will bump the
1374                          * rt6->rt6i_node->fn_sernum
1375                          * which will fail the next rt6_check() and
1376                          * invalidate the sk->sk_dst_cache.
1377                          */
1378                         ip6_ins_rt(nrt6);
1379                 }
1380         }
1381 }
1382
1383 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1384                                struct sk_buff *skb, u32 mtu)
1385 {
1386         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1387 }
1388
1389 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1390                      int oif, u32 mark)
1391 {
1392         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1393         struct dst_entry *dst;
1394         struct flowi6 fl6;
1395
1396         memset(&fl6, 0, sizeof(fl6));
1397         fl6.flowi6_oif = oif;
1398         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1399         fl6.daddr = iph->daddr;
1400         fl6.saddr = iph->saddr;
1401         fl6.flowlabel = ip6_flowinfo(iph);
1402
1403         dst = ip6_route_output(net, NULL, &fl6);
1404         if (!dst->error)
1405                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1406         dst_release(dst);
1407 }
1408 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1409
1410 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1411 {
1412         ip6_update_pmtu(skb, sock_net(sk), mtu,
1413                         sk->sk_bound_dev_if, sk->sk_mark);
1414 }
1415 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1416
1417 /* Handle redirects */
1418 struct ip6rd_flowi {
1419         struct flowi6 fl6;
1420         struct in6_addr gateway;
1421 };
1422
1423 static struct rt6_info *__ip6_route_redirect(struct net *net,
1424                                              struct fib6_table *table,
1425                                              struct flowi6 *fl6,
1426                                              int flags)
1427 {
1428         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1429         struct rt6_info *rt;
1430         struct fib6_node *fn;
1431
1432         /* Get the "current" route for this destination and
1433          * check if the redirect has come from approriate router.
1434          *
1435          * RFC 4861 specifies that redirects should only be
1436          * accepted if they come from the nexthop to the target.
1437          * Due to the way the routes are chosen, this notion
1438          * is a bit fuzzy and one might need to check all possible
1439          * routes.
1440          */
1441
1442         read_lock_bh(&table->tb6_lock);
1443         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1444 restart:
1445         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1446                 if (rt6_check_expired(rt))
1447                         continue;
1448                 if (rt->dst.error)
1449                         break;
1450                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1451                         continue;
1452                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1453                         continue;
1454                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1455                         continue;
1456                 break;
1457         }
1458
1459         if (!rt)
1460                 rt = net->ipv6.ip6_null_entry;
1461         else if (rt->dst.error) {
1462                 rt = net->ipv6.ip6_null_entry;
1463                 goto out;
1464         }
1465
1466         if (rt == net->ipv6.ip6_null_entry) {
1467                 fn = fib6_backtrack(fn, &fl6->saddr);
1468                 if (fn)
1469                         goto restart;
1470         }
1471
1472 out:
1473         dst_hold(&rt->dst);
1474
1475         read_unlock_bh(&table->tb6_lock);
1476
1477         return rt;
1478 };
1479
1480 static struct dst_entry *ip6_route_redirect(struct net *net,
1481                                         const struct flowi6 *fl6,
1482                                         const struct in6_addr *gateway)
1483 {
1484         int flags = RT6_LOOKUP_F_HAS_SADDR;
1485         struct ip6rd_flowi rdfl;
1486
1487         rdfl.fl6 = *fl6;
1488         rdfl.gateway = *gateway;
1489
1490         return fib6_rule_lookup(net, &rdfl.fl6,
1491                                 flags, __ip6_route_redirect);
1492 }
1493
1494 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1495 {
1496         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1497         struct dst_entry *dst;
1498         struct flowi6 fl6;
1499
1500         memset(&fl6, 0, sizeof(fl6));
1501         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1502         fl6.flowi6_oif = oif;
1503         fl6.flowi6_mark = mark;
1504         fl6.daddr = iph->daddr;
1505         fl6.saddr = iph->saddr;
1506         fl6.flowlabel = ip6_flowinfo(iph);
1507
1508         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1509         rt6_do_redirect(dst, NULL, skb);
1510         dst_release(dst);
1511 }
1512 EXPORT_SYMBOL_GPL(ip6_redirect);
1513
1514 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1515                             u32 mark)
1516 {
1517         const struct ipv6hdr *iph = ipv6_hdr(skb);
1518         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1519         struct dst_entry *dst;
1520         struct flowi6 fl6;
1521
1522         memset(&fl6, 0, sizeof(fl6));
1523         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1524         fl6.flowi6_oif = oif;
1525         fl6.flowi6_mark = mark;
1526         fl6.daddr = msg->dest;
1527         fl6.saddr = iph->daddr;
1528
1529         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1530         rt6_do_redirect(dst, NULL, skb);
1531         dst_release(dst);
1532 }
1533
1534 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1535 {
1536         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1537 }
1538 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1539
1540 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1541 {
1542         struct net_device *dev = dst->dev;
1543         unsigned int mtu = dst_mtu(dst);
1544         struct net *net = dev_net(dev);
1545
1546         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1547
1548         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1549                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1550
1551         /*
1552          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1553          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1554          * IPV6_MAXPLEN is also valid and means: "any MSS,
1555          * rely only on pmtu discovery"
1556          */
1557         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1558                 mtu = IPV6_MAXPLEN;
1559         return mtu;
1560 }
1561
1562 static unsigned int ip6_mtu(const struct dst_entry *dst)
1563 {
1564         const struct rt6_info *rt = (const struct rt6_info *)dst;
1565         unsigned int mtu = rt->rt6i_pmtu;
1566         struct inet6_dev *idev;
1567
1568         if (mtu)
1569                 goto out;
1570
1571         mtu = dst_metric_raw(dst, RTAX_MTU);
1572         if (mtu)
1573                 goto out;
1574
1575         mtu = IPV6_MIN_MTU;
1576
1577         rcu_read_lock();
1578         idev = __in6_dev_get(dst->dev);
1579         if (idev)
1580                 mtu = idev->cnf.mtu6;
1581         rcu_read_unlock();
1582
1583 out:
1584         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1585 }
1586
1587 static struct dst_entry *icmp6_dst_gc_list;
1588 static DEFINE_SPINLOCK(icmp6_dst_lock);
1589
1590 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1591                                   struct flowi6 *fl6)
1592 {
1593         struct dst_entry *dst;
1594         struct rt6_info *rt;
1595         struct inet6_dev *idev = in6_dev_get(dev);
1596         struct net *net = dev_net(dev);
1597
1598         if (unlikely(!idev))
1599                 return ERR_PTR(-ENODEV);
1600
1601         rt = ip6_dst_alloc(net, dev, 0);
1602         if (unlikely(!rt)) {
1603                 in6_dev_put(idev);
1604                 dst = ERR_PTR(-ENOMEM);
1605                 goto out;
1606         }
1607
1608         rt->dst.flags |= DST_HOST;
1609         rt->dst.output  = ip6_output;
1610         atomic_set(&rt->dst.__refcnt, 1);
1611         rt->rt6i_gateway  = fl6->daddr;
1612         rt->rt6i_dst.addr = fl6->daddr;
1613         rt->rt6i_dst.plen = 128;
1614         rt->rt6i_idev     = idev;
1615         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1616
1617         spin_lock_bh(&icmp6_dst_lock);
1618         rt->dst.next = icmp6_dst_gc_list;
1619         icmp6_dst_gc_list = &rt->dst;
1620         spin_unlock_bh(&icmp6_dst_lock);
1621
1622         fib6_force_start_gc(net);
1623
1624         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1625
1626 out:
1627         return dst;
1628 }
1629
1630 int icmp6_dst_gc(void)
1631 {
1632         struct dst_entry *dst, **pprev;
1633         int more = 0;
1634
1635         spin_lock_bh(&icmp6_dst_lock);
1636         pprev = &icmp6_dst_gc_list;
1637
1638         while ((dst = *pprev) != NULL) {
1639                 if (!atomic_read(&dst->__refcnt)) {
1640                         *pprev = dst->next;
1641                         dst_free(dst);
1642                 } else {
1643                         pprev = &dst->next;
1644                         ++more;
1645                 }
1646         }
1647
1648         spin_unlock_bh(&icmp6_dst_lock);
1649
1650         return more;
1651 }
1652
1653 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1654                             void *arg)
1655 {
1656         struct dst_entry *dst, **pprev;
1657
1658         spin_lock_bh(&icmp6_dst_lock);
1659         pprev = &icmp6_dst_gc_list;
1660         while ((dst = *pprev) != NULL) {
1661                 struct rt6_info *rt = (struct rt6_info *) dst;
1662                 if (func(rt, arg)) {
1663                         *pprev = dst->next;
1664                         dst_free(dst);
1665                 } else {
1666                         pprev = &dst->next;
1667                 }
1668         }
1669         spin_unlock_bh(&icmp6_dst_lock);
1670 }
1671
1672 static int ip6_dst_gc(struct dst_ops *ops)
1673 {
1674         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1675         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1676         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1677         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1678         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1679         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1680         int entries;
1681
1682         entries = dst_entries_get_fast(ops);
1683         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1684             entries <= rt_max_size)
1685                 goto out;
1686
1687         net->ipv6.ip6_rt_gc_expire++;
1688         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1689         entries = dst_entries_get_slow(ops);
1690         if (entries < ops->gc_thresh)
1691                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1692 out:
1693         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1694         return entries > rt_max_size;
1695 }
1696
1697 static int ip6_convert_metrics(struct mx6_config *mxc,
1698                                const struct fib6_config *cfg)
1699 {
1700         bool ecn_ca = false;
1701         struct nlattr *nla;
1702         int remaining;
1703         u32 *mp;
1704
1705         if (!cfg->fc_mx)
1706                 return 0;
1707
1708         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1709         if (unlikely(!mp))
1710                 return -ENOMEM;
1711
1712         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1713                 int type = nla_type(nla);
1714                 u32 val;
1715
1716                 if (!type)
1717                         continue;
1718                 if (unlikely(type > RTAX_MAX))
1719                         goto err;
1720
1721                 if (type == RTAX_CC_ALGO) {
1722                         char tmp[TCP_CA_NAME_MAX];
1723
1724                         nla_strlcpy(tmp, nla, sizeof(tmp));
1725                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1726                         if (val == TCP_CA_UNSPEC)
1727                                 goto err;
1728                 } else {
1729                         val = nla_get_u32(nla);
1730                 }
1731                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1732                         goto err;
1733
1734                 mp[type - 1] = val;
1735                 __set_bit(type - 1, mxc->mx_valid);
1736         }
1737
1738         if (ecn_ca) {
1739                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1740                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1741         }
1742
1743         mxc->mx = mp;
1744         return 0;
1745  err:
1746         kfree(mp);
1747         return -EINVAL;
1748 }
1749
1750 int ip6_route_info_create(struct fib6_config *cfg, struct rt6_info **rt_ret)
1751 {
1752         int err;
1753         struct net *net = cfg->fc_nlinfo.nl_net;
1754         struct rt6_info *rt = NULL;
1755         struct net_device *dev = NULL;
1756         struct inet6_dev *idev = NULL;
1757         struct fib6_table *table;
1758         int addr_type;
1759
1760         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1761                 return -EINVAL;
1762 #ifndef CONFIG_IPV6_SUBTREES
1763         if (cfg->fc_src_len)
1764                 return -EINVAL;
1765 #endif
1766         if (cfg->fc_ifindex) {
1767                 err = -ENODEV;
1768                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1769                 if (!dev)
1770                         goto out;
1771                 idev = in6_dev_get(dev);
1772                 if (!idev)
1773                         goto out;
1774         }
1775
1776         if (cfg->fc_metric == 0)
1777                 cfg->fc_metric = IP6_RT_PRIO_USER;
1778
1779         err = -ENOBUFS;
1780         if (cfg->fc_nlinfo.nlh &&
1781             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1782                 table = fib6_get_table(net, cfg->fc_table);
1783                 if (!table) {
1784                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1785                         table = fib6_new_table(net, cfg->fc_table);
1786                 }
1787         } else {
1788                 table = fib6_new_table(net, cfg->fc_table);
1789         }
1790
1791         if (!table)
1792                 goto out;
1793
1794         rt = ip6_dst_alloc(net, NULL,
1795                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1796
1797         if (!rt) {
1798                 err = -ENOMEM;
1799                 goto out;
1800         }
1801
1802         if (cfg->fc_flags & RTF_EXPIRES)
1803                 rt6_set_expires(rt, jiffies +
1804                                 clock_t_to_jiffies(cfg->fc_expires));
1805         else
1806                 rt6_clean_expires(rt);
1807
1808         if (cfg->fc_protocol == RTPROT_UNSPEC)
1809                 cfg->fc_protocol = RTPROT_BOOT;
1810         rt->rt6i_protocol = cfg->fc_protocol;
1811
1812         addr_type = ipv6_addr_type(&cfg->fc_dst);
1813
1814         if (addr_type & IPV6_ADDR_MULTICAST)
1815                 rt->dst.input = ip6_mc_input;
1816         else if (cfg->fc_flags & RTF_LOCAL)
1817                 rt->dst.input = ip6_input;
1818         else
1819                 rt->dst.input = ip6_forward;
1820
1821         rt->dst.output = ip6_output;
1822
1823         if (cfg->fc_encap) {
1824                 struct lwtunnel_state *lwtstate;
1825
1826                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1827                                            cfg->fc_encap, AF_INET6, cfg,
1828                                            &lwtstate);
1829                 if (err)
1830                         goto out;
1831                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1832                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1833                         rt->dst.lwtstate->orig_output = rt->dst.output;
1834                         rt->dst.output = lwtunnel_output;
1835                 }
1836                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1837                         rt->dst.lwtstate->orig_input = rt->dst.input;
1838                         rt->dst.input = lwtunnel_input;
1839                 }
1840         }
1841
1842         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1843         rt->rt6i_dst.plen = cfg->fc_dst_len;
1844         if (rt->rt6i_dst.plen == 128)
1845                 rt->dst.flags |= DST_HOST;
1846
1847 #ifdef CONFIG_IPV6_SUBTREES
1848         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1849         rt->rt6i_src.plen = cfg->fc_src_len;
1850 #endif
1851
1852         rt->rt6i_metric = cfg->fc_metric;
1853
1854         /* We cannot add true routes via loopback here,
1855            they would result in kernel looping; promote them to reject routes
1856          */
1857         if ((cfg->fc_flags & RTF_REJECT) ||
1858             (dev && (dev->flags & IFF_LOOPBACK) &&
1859              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1860              !(cfg->fc_flags & RTF_LOCAL))) {
1861                 /* hold loopback dev/idev if we haven't done so. */
1862                 if (dev != net->loopback_dev) {
1863                         if (dev) {
1864                                 dev_put(dev);
1865                                 in6_dev_put(idev);
1866                         }
1867                         dev = net->loopback_dev;
1868                         dev_hold(dev);
1869                         idev = in6_dev_get(dev);
1870                         if (!idev) {
1871                                 err = -ENODEV;
1872                                 goto out;
1873                         }
1874                 }
1875                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1876                 switch (cfg->fc_type) {
1877                 case RTN_BLACKHOLE:
1878                         rt->dst.error = -EINVAL;
1879                         rt->dst.output = dst_discard_sk;
1880                         rt->dst.input = dst_discard;
1881                         break;
1882                 case RTN_PROHIBIT:
1883                         rt->dst.error = -EACCES;
1884                         rt->dst.output = ip6_pkt_prohibit_out;
1885                         rt->dst.input = ip6_pkt_prohibit;
1886                         break;
1887                 case RTN_THROW:
1888                 default:
1889                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1890                                         : -ENETUNREACH;
1891                         rt->dst.output = ip6_pkt_discard_out;
1892                         rt->dst.input = ip6_pkt_discard;
1893                         break;
1894                 }
1895                 goto install_route;
1896         }
1897
1898         if (cfg->fc_flags & RTF_GATEWAY) {
1899                 const struct in6_addr *gw_addr;
1900                 int gwa_type;
1901
1902                 gw_addr = &cfg->fc_gateway;
1903                 gwa_type = ipv6_addr_type(gw_addr);
1904
1905                 /* if gw_addr is local we will fail to detect this in case
1906                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1907                  * will return already-added prefix route via interface that
1908                  * prefix route was assigned to, which might be non-loopback.
1909                  */
1910                 err = -EINVAL;
1911                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1912                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1913                                             dev : NULL, 0, 0))
1914                         goto out;
1915
1916                 rt->rt6i_gateway = *gw_addr;
1917
1918                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1919                         struct rt6_info *grt;
1920
1921                         /* IPv6 strictly inhibits using not link-local
1922                            addresses as nexthop address.
1923                            Otherwise, router will not able to send redirects.
1924                            It is very good, but in some (rare!) circumstances
1925                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1926                            some exceptions. --ANK
1927                          */
1928                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1929                                 goto out;
1930
1931                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1932
1933                         err = -EHOSTUNREACH;
1934                         if (!grt)
1935                                 goto out;
1936                         if (dev) {
1937                                 if (dev != grt->dst.dev) {
1938                                         ip6_rt_put(grt);
1939                                         goto out;
1940                                 }
1941                         } else {
1942                                 dev = grt->dst.dev;
1943                                 idev = grt->rt6i_idev;
1944                                 dev_hold(dev);
1945                                 in6_dev_hold(grt->rt6i_idev);
1946                         }
1947                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1948                                 err = 0;
1949                         ip6_rt_put(grt);
1950
1951                         if (err)
1952                                 goto out;
1953                 }
1954                 err = -EINVAL;
1955                 if (!dev || (dev->flags & IFF_LOOPBACK))
1956                         goto out;
1957         }
1958
1959         err = -ENODEV;
1960         if (!dev)
1961                 goto out;
1962
1963         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1964                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1965                         err = -EINVAL;
1966                         goto out;
1967                 }
1968                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1969                 rt->rt6i_prefsrc.plen = 128;
1970         } else
1971                 rt->rt6i_prefsrc.plen = 0;
1972
1973         rt->rt6i_flags = cfg->fc_flags;
1974
1975 install_route:
1976         rt->dst.dev = dev;
1977         rt->rt6i_idev = idev;
1978         rt->rt6i_table = table;
1979
1980         cfg->fc_nlinfo.nl_net = dev_net(dev);
1981
1982         *rt_ret = rt;
1983
1984         return 0;
1985 out:
1986         if (dev)
1987                 dev_put(dev);
1988         if (idev)
1989                 in6_dev_put(idev);
1990         if (rt)
1991                 dst_free(&rt->dst);
1992
1993         *rt_ret = NULL;
1994
1995         return err;
1996 }
1997
1998 int ip6_route_add(struct fib6_config *cfg)
1999 {
2000         struct mx6_config mxc = { .mx = NULL, };
2001         struct rt6_info *rt = NULL;
2002         int err;
2003
2004         err = ip6_route_info_create(cfg, &rt);
2005         if (err)
2006                 goto out;
2007
2008         err = ip6_convert_metrics(&mxc, cfg);
2009         if (err)
2010                 goto out;
2011
2012         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2013
2014         kfree(mxc.mx);
2015
2016         return err;
2017 out:
2018         if (rt)
2019                 dst_free(&rt->dst);
2020
2021         return err;
2022 }
2023
2024 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2025 {
2026         int err;
2027         struct fib6_table *table;
2028         struct net *net = dev_net(rt->dst.dev);
2029
2030         if (rt == net->ipv6.ip6_null_entry ||
2031             rt->dst.flags & DST_NOCACHE) {
2032                 err = -ENOENT;
2033                 goto out;
2034         }
2035
2036         table = rt->rt6i_table;
2037         write_lock_bh(&table->tb6_lock);
2038         err = fib6_del(rt, info);
2039         write_unlock_bh(&table->tb6_lock);
2040
2041 out:
2042         ip6_rt_put(rt);
2043         return err;
2044 }
2045
2046 int ip6_del_rt(struct rt6_info *rt)
2047 {
2048         struct nl_info info = {
2049                 .nl_net = dev_net(rt->dst.dev),
2050         };
2051         return __ip6_del_rt(rt, &info);
2052 }
2053
2054 static int ip6_route_del(struct fib6_config *cfg)
2055 {
2056         struct fib6_table *table;
2057         struct fib6_node *fn;
2058         struct rt6_info *rt;
2059         int err = -ESRCH;
2060
2061         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2062         if (!table)
2063                 return err;
2064
2065         read_lock_bh(&table->tb6_lock);
2066
2067         fn = fib6_locate(&table->tb6_root,
2068                          &cfg->fc_dst, cfg->fc_dst_len,
2069                          &cfg->fc_src, cfg->fc_src_len);
2070
2071         if (fn) {
2072                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2073                         if ((rt->rt6i_flags & RTF_CACHE) &&
2074                             !(cfg->fc_flags & RTF_CACHE))
2075                                 continue;
2076                         if (cfg->fc_ifindex &&
2077                             (!rt->dst.dev ||
2078                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2079                                 continue;
2080                         if (cfg->fc_flags & RTF_GATEWAY &&
2081                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2082                                 continue;
2083                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2084                                 continue;
2085                         dst_hold(&rt->dst);
2086                         read_unlock_bh(&table->tb6_lock);
2087
2088                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2089                 }
2090         }
2091         read_unlock_bh(&table->tb6_lock);
2092
2093         return err;
2094 }
2095
2096 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2097 {
2098         struct net *net = dev_net(skb->dev);
2099         struct netevent_redirect netevent;
2100         struct rt6_info *rt, *nrt = NULL;
2101         struct ndisc_options ndopts;
2102         struct inet6_dev *in6_dev;
2103         struct neighbour *neigh;
2104         struct rd_msg *msg;
2105         int optlen, on_link;
2106         u8 *lladdr;
2107
2108         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2109         optlen -= sizeof(*msg);
2110
2111         if (optlen < 0) {
2112                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2113                 return;
2114         }
2115
2116         msg = (struct rd_msg *)icmp6_hdr(skb);
2117
2118         if (ipv6_addr_is_multicast(&msg->dest)) {
2119                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2120                 return;
2121         }
2122
2123         on_link = 0;
2124         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2125                 on_link = 1;
2126         } else if (ipv6_addr_type(&msg->target) !=
2127                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2128                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2129                 return;
2130         }
2131
2132         in6_dev = __in6_dev_get(skb->dev);
2133         if (!in6_dev)
2134                 return;
2135         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2136                 return;
2137
2138         /* RFC2461 8.1:
2139          *      The IP source address of the Redirect MUST be the same as the current
2140          *      first-hop router for the specified ICMP Destination Address.
2141          */
2142
2143         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2144                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2145                 return;
2146         }
2147
2148         lladdr = NULL;
2149         if (ndopts.nd_opts_tgt_lladdr) {
2150                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2151                                              skb->dev);
2152                 if (!lladdr) {
2153                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2154                         return;
2155                 }
2156         }
2157
2158         rt = (struct rt6_info *) dst;
2159         if (rt == net->ipv6.ip6_null_entry) {
2160                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2161                 return;
2162         }
2163
2164         /* Redirect received -> path was valid.
2165          * Look, redirects are sent only in response to data packets,
2166          * so that this nexthop apparently is reachable. --ANK
2167          */
2168         dst_confirm(&rt->dst);
2169
2170         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2171         if (!neigh)
2172                 return;
2173
2174         /*
2175          *      We have finally decided to accept it.
2176          */
2177
2178         neigh_update(neigh, lladdr, NUD_STALE,
2179                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2180                      NEIGH_UPDATE_F_OVERRIDE|
2181                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2182                                      NEIGH_UPDATE_F_ISROUTER))
2183                      );
2184
2185         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2186         if (!nrt)
2187                 goto out;
2188
2189         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2190         if (on_link)
2191                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2192
2193         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2194
2195         if (ip6_ins_rt(nrt))
2196                 goto out;
2197
2198         netevent.old = &rt->dst;
2199         netevent.new = &nrt->dst;
2200         netevent.daddr = &msg->dest;
2201         netevent.neigh = neigh;
2202         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2203
2204         if (rt->rt6i_flags & RTF_CACHE) {
2205                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2206                 ip6_del_rt(rt);
2207         }
2208
2209 out:
2210         neigh_release(neigh);
2211 }
2212
2213 /*
2214  *      Misc support functions
2215  */
2216
2217 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2218 {
2219         BUG_ON(from->dst.from);
2220
2221         rt->rt6i_flags &= ~RTF_EXPIRES;
2222         dst_hold(&from->dst);
2223         rt->dst.from = &from->dst;
2224         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2225 }
2226
2227 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2228 {
2229         rt->dst.input = ort->dst.input;
2230         rt->dst.output = ort->dst.output;
2231         rt->rt6i_dst = ort->rt6i_dst;
2232         rt->dst.error = ort->dst.error;
2233         rt->rt6i_idev = ort->rt6i_idev;
2234         if (rt->rt6i_idev)
2235                 in6_dev_hold(rt->rt6i_idev);
2236         rt->dst.lastuse = jiffies;
2237         rt->rt6i_gateway = ort->rt6i_gateway;
2238         rt->rt6i_flags = ort->rt6i_flags;
2239         rt6_set_from(rt, ort);
2240         rt->rt6i_metric = ort->rt6i_metric;
2241 #ifdef CONFIG_IPV6_SUBTREES
2242         rt->rt6i_src = ort->rt6i_src;
2243 #endif
2244         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2245         rt->rt6i_table = ort->rt6i_table;
2246         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2247 }
2248
2249 #ifdef CONFIG_IPV6_ROUTE_INFO
2250 static struct rt6_info *rt6_get_route_info(struct net *net,
2251                                            const struct in6_addr *prefix, int prefixlen,
2252                                            const struct in6_addr *gwaddr, int ifindex)
2253 {
2254         struct fib6_node *fn;
2255         struct rt6_info *rt = NULL;
2256         struct fib6_table *table;
2257
2258         table = fib6_get_table(net, RT6_TABLE_INFO);
2259         if (!table)
2260                 return NULL;
2261
2262         read_lock_bh(&table->tb6_lock);
2263         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2264         if (!fn)
2265                 goto out;
2266
2267         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2268                 if (rt->dst.dev->ifindex != ifindex)
2269                         continue;
2270                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2271                         continue;
2272                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2273                         continue;
2274                 dst_hold(&rt->dst);
2275                 break;
2276         }
2277 out:
2278         read_unlock_bh(&table->tb6_lock);
2279         return rt;
2280 }
2281
2282 static struct rt6_info *rt6_add_route_info(struct net *net,
2283                                            const struct in6_addr *prefix, int prefixlen,
2284                                            const struct in6_addr *gwaddr, int ifindex,
2285                                            unsigned int pref)
2286 {
2287         struct fib6_config cfg = {
2288                 .fc_table       = RT6_TABLE_INFO,
2289                 .fc_metric      = IP6_RT_PRIO_USER,
2290                 .fc_ifindex     = ifindex,
2291                 .fc_dst_len     = prefixlen,
2292                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2293                                   RTF_UP | RTF_PREF(pref),
2294                 .fc_nlinfo.portid = 0,
2295                 .fc_nlinfo.nlh = NULL,
2296                 .fc_nlinfo.nl_net = net,
2297         };
2298
2299         cfg.fc_dst = *prefix;
2300         cfg.fc_gateway = *gwaddr;
2301
2302         /* We should treat it as a default route if prefix length is 0. */
2303         if (!prefixlen)
2304                 cfg.fc_flags |= RTF_DEFAULT;
2305
2306         ip6_route_add(&cfg);
2307
2308         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2309 }
2310 #endif
2311
2312 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2313 {
2314         struct rt6_info *rt;
2315         struct fib6_table *table;
2316
2317         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2318         if (!table)
2319                 return NULL;
2320
2321         read_lock_bh(&table->tb6_lock);
2322         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2323                 if (dev == rt->dst.dev &&
2324                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2325                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2326                         break;
2327         }
2328         if (rt)
2329                 dst_hold(&rt->dst);
2330         read_unlock_bh(&table->tb6_lock);
2331         return rt;
2332 }
2333
2334 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2335                                      struct net_device *dev,
2336                                      unsigned int pref)
2337 {
2338         struct fib6_config cfg = {
2339                 .fc_table       = RT6_TABLE_DFLT,
2340                 .fc_metric      = IP6_RT_PRIO_USER,
2341                 .fc_ifindex     = dev->ifindex,
2342                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2343                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2344                 .fc_nlinfo.portid = 0,
2345                 .fc_nlinfo.nlh = NULL,
2346                 .fc_nlinfo.nl_net = dev_net(dev),
2347         };
2348
2349         cfg.fc_gateway = *gwaddr;
2350
2351         ip6_route_add(&cfg);
2352
2353         return rt6_get_dflt_router(gwaddr, dev);
2354 }
2355
2356 void rt6_purge_dflt_routers(struct net *net)
2357 {
2358         struct rt6_info *rt;
2359         struct fib6_table *table;
2360
2361         /* NOTE: Keep consistent with rt6_get_dflt_router */
2362         table = fib6_get_table(net, RT6_TABLE_DFLT);
2363         if (!table)
2364                 return;
2365
2366 restart:
2367         read_lock_bh(&table->tb6_lock);
2368         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2369                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2370                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2371                         dst_hold(&rt->dst);
2372                         read_unlock_bh(&table->tb6_lock);
2373                         ip6_del_rt(rt);
2374                         goto restart;
2375                 }
2376         }
2377         read_unlock_bh(&table->tb6_lock);
2378 }
2379
2380 static void rtmsg_to_fib6_config(struct net *net,
2381                                  struct in6_rtmsg *rtmsg,
2382                                  struct fib6_config *cfg)
2383 {
2384         memset(cfg, 0, sizeof(*cfg));
2385
2386         cfg->fc_table = RT6_TABLE_MAIN;
2387         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2388         cfg->fc_metric = rtmsg->rtmsg_metric;
2389         cfg->fc_expires = rtmsg->rtmsg_info;
2390         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2391         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2392         cfg->fc_flags = rtmsg->rtmsg_flags;
2393
2394         cfg->fc_nlinfo.nl_net = net;
2395
2396         cfg->fc_dst = rtmsg->rtmsg_dst;
2397         cfg->fc_src = rtmsg->rtmsg_src;
2398         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2399 }
2400
2401 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2402 {
2403         struct fib6_config cfg;
2404         struct in6_rtmsg rtmsg;
2405         int err;
2406
2407         switch (cmd) {
2408         case SIOCADDRT:         /* Add a route */
2409         case SIOCDELRT:         /* Delete a route */
2410                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2411                         return -EPERM;
2412                 err = copy_from_user(&rtmsg, arg,
2413                                      sizeof(struct in6_rtmsg));
2414                 if (err)
2415                         return -EFAULT;
2416
2417                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2418
2419                 rtnl_lock();
2420                 switch (cmd) {
2421                 case SIOCADDRT:
2422                         err = ip6_route_add(&cfg);
2423                         break;
2424                 case SIOCDELRT:
2425                         err = ip6_route_del(&cfg);
2426                         break;
2427                 default:
2428                         err = -EINVAL;
2429                 }
2430                 rtnl_unlock();
2431
2432                 return err;
2433         }
2434
2435         return -EINVAL;
2436 }
2437
2438 /*
2439  *      Drop the packet on the floor
2440  */
2441
2442 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2443 {
2444         int type;
2445         struct dst_entry *dst = skb_dst(skb);
2446         switch (ipstats_mib_noroutes) {
2447         case IPSTATS_MIB_INNOROUTES:
2448                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2449                 if (type == IPV6_ADDR_ANY) {
2450                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2451                                       IPSTATS_MIB_INADDRERRORS);
2452                         break;
2453                 }
2454                 /* FALLTHROUGH */
2455         case IPSTATS_MIB_OUTNOROUTES:
2456                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2457                               ipstats_mib_noroutes);
2458                 break;
2459         }
2460         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2461         kfree_skb(skb);
2462         return 0;
2463 }
2464
2465 static int ip6_pkt_discard(struct sk_buff *skb)
2466 {
2467         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2468 }
2469
2470 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2471 {
2472         skb->dev = skb_dst(skb)->dev;
2473         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2474 }
2475
2476 static int ip6_pkt_prohibit(struct sk_buff *skb)
2477 {
2478         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2479 }
2480
2481 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2482 {
2483         skb->dev = skb_dst(skb)->dev;
2484         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2485 }
2486
2487 /*
2488  *      Allocate a dst for local (unicast / anycast) address.
2489  */
2490
2491 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2492                                     const struct in6_addr *addr,
2493                                     bool anycast)
2494 {
2495         struct net *net = dev_net(idev->dev);
2496         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2497                                             DST_NOCOUNT);
2498         if (!rt)
2499                 return ERR_PTR(-ENOMEM);
2500
2501         in6_dev_hold(idev);
2502
2503         rt->dst.flags |= DST_HOST;
2504         rt->dst.input = ip6_input;
2505         rt->dst.output = ip6_output;
2506         rt->rt6i_idev = idev;
2507
2508         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2509         if (anycast)
2510                 rt->rt6i_flags |= RTF_ANYCAST;
2511         else
2512                 rt->rt6i_flags |= RTF_LOCAL;
2513
2514         rt->rt6i_gateway  = *addr;
2515         rt->rt6i_dst.addr = *addr;
2516         rt->rt6i_dst.plen = 128;
2517         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2518         rt->dst.flags |= DST_NOCACHE;
2519
2520         atomic_set(&rt->dst.__refcnt, 1);
2521
2522         return rt;
2523 }
2524
2525 int ip6_route_get_saddr(struct net *net,
2526                         struct rt6_info *rt,
2527                         const struct in6_addr *daddr,
2528                         unsigned int prefs,
2529                         struct in6_addr *saddr)
2530 {
2531         struct inet6_dev *idev =
2532                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2533         int err = 0;
2534         if (rt && rt->rt6i_prefsrc.plen)
2535                 *saddr = rt->rt6i_prefsrc.addr;
2536         else
2537                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2538                                          daddr, prefs, saddr);
2539         return err;
2540 }
2541
2542 /* remove deleted ip from prefsrc entries */
2543 struct arg_dev_net_ip {
2544         struct net_device *dev;
2545         struct net *net;
2546         struct in6_addr *addr;
2547 };
2548
2549 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2550 {
2551         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2552         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2553         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2554
2555         if (((void *)rt->dst.dev == dev || !dev) &&
2556             rt != net->ipv6.ip6_null_entry &&
2557             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2558                 /* remove prefsrc entry */
2559                 rt->rt6i_prefsrc.plen = 0;
2560         }
2561         return 0;
2562 }
2563
2564 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2565 {
2566         struct net *net = dev_net(ifp->idev->dev);
2567         struct arg_dev_net_ip adni = {
2568                 .dev = ifp->idev->dev,
2569                 .net = net,
2570                 .addr = &ifp->addr,
2571         };
2572         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2573 }
2574
2575 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2576 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2577
2578 /* Remove routers and update dst entries when gateway turn into host. */
2579 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2580 {
2581         struct in6_addr *gateway = (struct in6_addr *)arg;
2582
2583         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2584              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2585              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2586                 return -1;
2587         }
2588         return 0;
2589 }
2590
2591 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2592 {
2593         fib6_clean_all(net, fib6_clean_tohost, gateway);
2594 }
2595
2596 struct arg_dev_net {
2597         struct net_device *dev;
2598         struct net *net;
2599 };
2600
2601 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2602 {
2603         const struct arg_dev_net *adn = arg;
2604         const struct net_device *dev = adn->dev;
2605
2606         if ((rt->dst.dev == dev || !dev) &&
2607             rt != adn->net->ipv6.ip6_null_entry)
2608                 return -1;
2609
2610         return 0;
2611 }
2612
2613 void rt6_ifdown(struct net *net, struct net_device *dev)
2614 {
2615         struct arg_dev_net adn = {
2616                 .dev = dev,
2617                 .net = net,
2618         };
2619
2620         fib6_clean_all(net, fib6_ifdown, &adn);
2621         icmp6_clean_all(fib6_ifdown, &adn);
2622         rt6_uncached_list_flush_dev(net, dev);
2623 }
2624
2625 struct rt6_mtu_change_arg {
2626         struct net_device *dev;
2627         unsigned int mtu;
2628 };
2629
2630 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2631 {
2632         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2633         struct inet6_dev *idev;
2634
2635         /* In IPv6 pmtu discovery is not optional,
2636            so that RTAX_MTU lock cannot disable it.
2637            We still use this lock to block changes
2638            caused by addrconf/ndisc.
2639         */
2640
2641         idev = __in6_dev_get(arg->dev);
2642         if (!idev)
2643                 return 0;
2644
2645         /* For administrative MTU increase, there is no way to discover
2646            IPv6 PMTU increase, so PMTU increase should be updated here.
2647            Since RFC 1981 doesn't include administrative MTU increase
2648            update PMTU increase is a MUST. (i.e. jumbo frame)
2649          */
2650         /*
2651            If new MTU is less than route PMTU, this new MTU will be the
2652            lowest MTU in the path, update the route PMTU to reflect PMTU
2653            decreases; if new MTU is greater than route PMTU, and the
2654            old MTU is the lowest MTU in the path, update the route PMTU
2655            to reflect the increase. In this case if the other nodes' MTU
2656            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2657            PMTU discouvery.
2658          */
2659         if (rt->dst.dev == arg->dev &&
2660             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2661                 if (rt->rt6i_flags & RTF_CACHE) {
2662                         /* For RTF_CACHE with rt6i_pmtu == 0
2663                          * (i.e. a redirected route),
2664                          * the metrics of its rt->dst.from has already
2665                          * been updated.
2666                          */
2667                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2668                                 rt->rt6i_pmtu = arg->mtu;
2669                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2670                            (dst_mtu(&rt->dst) < arg->mtu &&
2671                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2672                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2673                 }
2674         }
2675         return 0;
2676 }
2677
2678 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2679 {
2680         struct rt6_mtu_change_arg arg = {
2681                 .dev = dev,
2682                 .mtu = mtu,
2683         };
2684
2685         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2686 }
2687
2688 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2689         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2690         [RTA_OIF]               = { .type = NLA_U32 },
2691         [RTA_IIF]               = { .type = NLA_U32 },
2692         [RTA_PRIORITY]          = { .type = NLA_U32 },
2693         [RTA_METRICS]           = { .type = NLA_NESTED },
2694         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2695         [RTA_PREF]              = { .type = NLA_U8 },
2696         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2697         [RTA_ENCAP]             = { .type = NLA_NESTED },
2698 };
2699
2700 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2701                               struct fib6_config *cfg)
2702 {
2703         struct rtmsg *rtm;
2704         struct nlattr *tb[RTA_MAX+1];
2705         unsigned int pref;
2706         int err;
2707
2708         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2709         if (err < 0)
2710                 goto errout;
2711
2712         err = -EINVAL;
2713         rtm = nlmsg_data(nlh);
2714         memset(cfg, 0, sizeof(*cfg));
2715
2716         cfg->fc_table = rtm->rtm_table;
2717         cfg->fc_dst_len = rtm->rtm_dst_len;
2718         cfg->fc_src_len = rtm->rtm_src_len;
2719         cfg->fc_flags = RTF_UP;
2720         cfg->fc_protocol = rtm->rtm_protocol;
2721         cfg->fc_type = rtm->rtm_type;
2722
2723         if (rtm->rtm_type == RTN_UNREACHABLE ||
2724             rtm->rtm_type == RTN_BLACKHOLE ||
2725             rtm->rtm_type == RTN_PROHIBIT ||
2726             rtm->rtm_type == RTN_THROW)
2727                 cfg->fc_flags |= RTF_REJECT;
2728
2729         if (rtm->rtm_type == RTN_LOCAL)
2730                 cfg->fc_flags |= RTF_LOCAL;
2731
2732         if (rtm->rtm_flags & RTM_F_CLONED)
2733                 cfg->fc_flags |= RTF_CACHE;
2734
2735         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2736         cfg->fc_nlinfo.nlh = nlh;
2737         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2738
2739         if (tb[RTA_GATEWAY]) {
2740                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2741                 cfg->fc_flags |= RTF_GATEWAY;
2742         }
2743
2744         if (tb[RTA_DST]) {
2745                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2746
2747                 if (nla_len(tb[RTA_DST]) < plen)
2748                         goto errout;
2749
2750                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2751         }
2752
2753         if (tb[RTA_SRC]) {
2754                 int plen = (rtm->rtm_src_len + 7) >> 3;
2755
2756                 if (nla_len(tb[RTA_SRC]) < plen)
2757                         goto errout;
2758
2759                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2760         }
2761
2762         if (tb[RTA_PREFSRC])
2763                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2764
2765         if (tb[RTA_OIF])
2766                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2767
2768         if (tb[RTA_PRIORITY])
2769                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2770
2771         if (tb[RTA_METRICS]) {
2772                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2773                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2774         }
2775
2776         if (tb[RTA_TABLE])
2777                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2778
2779         if (tb[RTA_MULTIPATH]) {
2780                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2781                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2782         }
2783
2784         if (tb[RTA_PREF]) {
2785                 pref = nla_get_u8(tb[RTA_PREF]);
2786                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2787                     pref != ICMPV6_ROUTER_PREF_HIGH)
2788                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2789                 cfg->fc_flags |= RTF_PREF(pref);
2790         }
2791
2792         if (tb[RTA_ENCAP])
2793                 cfg->fc_encap = tb[RTA_ENCAP];
2794
2795         if (tb[RTA_ENCAP_TYPE])
2796                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2797
2798         err = 0;
2799 errout:
2800         return err;
2801 }
2802
2803 struct rt6_nh {
2804         struct rt6_info *rt6_info;
2805         struct fib6_config r_cfg;
2806         struct mx6_config mxc;
2807         struct list_head next;
2808 };
2809
2810 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2811 {
2812         struct rt6_nh *nh;
2813
2814         list_for_each_entry(nh, rt6_nh_list, next) {
2815                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2816                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2817                         nh->r_cfg.fc_ifindex);
2818         }
2819 }
2820
2821 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2822                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2823 {
2824         struct rt6_nh *nh;
2825         struct rt6_info *rtnh;
2826         int err = -EEXIST;
2827
2828         list_for_each_entry(nh, rt6_nh_list, next) {
2829                 /* check if rt6_info already exists */
2830                 rtnh = nh->rt6_info;
2831
2832                 if (rtnh->dst.dev == rt->dst.dev &&
2833                     rtnh->rt6i_idev == rt->rt6i_idev &&
2834                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2835                                     &rt->rt6i_gateway))
2836                         return err;
2837         }
2838
2839         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2840         if (!nh)
2841                 return -ENOMEM;
2842         nh->rt6_info = rt;
2843         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2844         if (err) {
2845                 kfree(nh);
2846                 return err;
2847         }
2848         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2849         list_add_tail(&nh->next, rt6_nh_list);
2850
2851         return 0;
2852 }
2853
2854 static int ip6_route_multipath_add(struct fib6_config *cfg)
2855 {
2856         struct fib6_config r_cfg;
2857         struct rtnexthop *rtnh;
2858         struct rt6_info *rt;
2859         struct rt6_nh *err_nh;
2860         struct rt6_nh *nh, *nh_safe;
2861         int remaining;
2862         int attrlen;
2863         int err = 1;
2864         int nhn = 0;
2865         int replace = (cfg->fc_nlinfo.nlh &&
2866                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2867         LIST_HEAD(rt6_nh_list);
2868
2869         remaining = cfg->fc_mp_len;
2870         rtnh = (struct rtnexthop *)cfg->fc_mp;
2871
2872         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2873          * rt6_info structs per nexthop
2874          */
2875         while (rtnh_ok(rtnh, remaining)) {
2876                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2877                 if (rtnh->rtnh_ifindex)
2878                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2879
2880                 attrlen = rtnh_attrlen(rtnh);
2881                 if (attrlen > 0) {
2882                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2883
2884                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2885                         if (nla) {
2886                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2887                                 r_cfg.fc_flags |= RTF_GATEWAY;
2888                         }
2889                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2890                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2891                         if (nla)
2892                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2893                 }
2894
2895                 err = ip6_route_info_create(&r_cfg, &rt);
2896                 if (err)
2897                         goto cleanup;
2898
2899                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2900                 if (err) {
2901                         dst_free(&rt->dst);
2902                         goto cleanup;
2903                 }
2904
2905                 rtnh = rtnh_next(rtnh, &remaining);
2906         }
2907
2908         err_nh = NULL;
2909         list_for_each_entry(nh, &rt6_nh_list, next) {
2910                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2911                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2912                 nh->rt6_info = NULL;
2913                 if (err) {
2914                         if (replace && nhn)
2915                                 ip6_print_replace_route_err(&rt6_nh_list);
2916                         err_nh = nh;
2917                         goto add_errout;
2918                 }
2919
2920                 /* Because each route is added like a single route we remove
2921                  * these flags after the first nexthop: if there is a collision,
2922                  * we have already failed to add the first nexthop:
2923                  * fib6_add_rt2node() has rejected it; when replacing, old
2924                  * nexthops have been replaced by first new, the rest should
2925                  * be added to it.
2926                  */
2927                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2928                                                      NLM_F_REPLACE);
2929                 nhn++;
2930         }
2931
2932         goto cleanup;
2933
2934 add_errout:
2935         /* Delete routes that were already added */
2936         list_for_each_entry(nh, &rt6_nh_list, next) {
2937                 if (err_nh == nh)
2938                         break;
2939                 ip6_route_del(&nh->r_cfg);
2940         }
2941
2942 cleanup:
2943         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2944                 if (nh->rt6_info)
2945                         dst_free(&nh->rt6_info->dst);
2946                 kfree(nh->mxc.mx);
2947                 list_del(&nh->next);
2948                 kfree(nh);
2949         }
2950
2951         return err;
2952 }
2953
2954 static int ip6_route_multipath_del(struct fib6_config *cfg)
2955 {
2956         struct fib6_config r_cfg;
2957         struct rtnexthop *rtnh;
2958         int remaining;
2959         int attrlen;
2960         int err = 1, last_err = 0;
2961
2962         remaining = cfg->fc_mp_len;
2963         rtnh = (struct rtnexthop *)cfg->fc_mp;
2964
2965         /* Parse a Multipath Entry */
2966         while (rtnh_ok(rtnh, remaining)) {
2967                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2968                 if (rtnh->rtnh_ifindex)
2969                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2970
2971                 attrlen = rtnh_attrlen(rtnh);
2972                 if (attrlen > 0) {
2973                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2974
2975                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2976                         if (nla) {
2977                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2978                                 r_cfg.fc_flags |= RTF_GATEWAY;
2979                         }
2980                 }
2981                 err = ip6_route_del(&r_cfg);
2982                 if (err)
2983                         last_err = err;
2984
2985                 rtnh = rtnh_next(rtnh, &remaining);
2986         }
2987
2988         return last_err;
2989 }
2990
2991 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2992 {
2993         struct fib6_config cfg;
2994         int err;
2995
2996         err = rtm_to_fib6_config(skb, nlh, &cfg);
2997         if (err < 0)
2998                 return err;
2999
3000         if (cfg.fc_mp)
3001                 return ip6_route_multipath_del(&cfg);
3002         else
3003                 return ip6_route_del(&cfg);
3004 }
3005
3006 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3007 {
3008         struct fib6_config cfg;
3009         int err;
3010
3011         err = rtm_to_fib6_config(skb, nlh, &cfg);
3012         if (err < 0)
3013                 return err;
3014
3015         if (cfg.fc_mp)
3016                 return ip6_route_multipath_add(&cfg);
3017         else
3018                 return ip6_route_add(&cfg);
3019 }
3020
3021 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3022 {
3023         return NLMSG_ALIGN(sizeof(struct rtmsg))
3024                + nla_total_size(16) /* RTA_SRC */
3025                + nla_total_size(16) /* RTA_DST */
3026                + nla_total_size(16) /* RTA_GATEWAY */
3027                + nla_total_size(16) /* RTA_PREFSRC */
3028                + nla_total_size(4) /* RTA_TABLE */
3029                + nla_total_size(4) /* RTA_IIF */
3030                + nla_total_size(4) /* RTA_OIF */
3031                + nla_total_size(4) /* RTA_PRIORITY */
3032                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3033                + nla_total_size(sizeof(struct rta_cacheinfo))
3034                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3035                + nla_total_size(1) /* RTA_PREF */
3036                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3037 }
3038
3039 static int rt6_fill_node(struct net *net,
3040                          struct sk_buff *skb, struct rt6_info *rt,
3041                          struct in6_addr *dst, struct in6_addr *src,
3042                          int iif, int type, u32 portid, u32 seq,
3043                          int prefix, int nowait, unsigned int flags)
3044 {
3045         u32 metrics[RTAX_MAX];
3046         struct rtmsg *rtm;
3047         struct nlmsghdr *nlh;
3048         long expires;
3049         u32 table;
3050
3051         if (prefix) {   /* user wants prefix routes only */
3052                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3053                         /* success since this is not a prefix route */
3054                         return 1;
3055                 }
3056         }
3057
3058         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3059         if (!nlh)
3060                 return -EMSGSIZE;
3061
3062         rtm = nlmsg_data(nlh);
3063         rtm->rtm_family = AF_INET6;
3064         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3065         rtm->rtm_src_len = rt->rt6i_src.plen;
3066         rtm->rtm_tos = 0;
3067         if (rt->rt6i_table)
3068                 table = rt->rt6i_table->tb6_id;
3069         else
3070                 table = RT6_TABLE_UNSPEC;
3071         rtm->rtm_table = table;
3072         if (nla_put_u32(skb, RTA_TABLE, table))
3073                 goto nla_put_failure;
3074         if (rt->rt6i_flags & RTF_REJECT) {
3075                 switch (rt->dst.error) {
3076                 case -EINVAL:
3077                         rtm->rtm_type = RTN_BLACKHOLE;
3078                         break;
3079                 case -EACCES:
3080                         rtm->rtm_type = RTN_PROHIBIT;
3081                         break;
3082                 case -EAGAIN:
3083                         rtm->rtm_type = RTN_THROW;
3084                         break;
3085                 default:
3086                         rtm->rtm_type = RTN_UNREACHABLE;
3087                         break;
3088                 }
3089         }
3090         else if (rt->rt6i_flags & RTF_LOCAL)
3091                 rtm->rtm_type = RTN_LOCAL;
3092         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3093                 rtm->rtm_type = RTN_LOCAL;
3094         else
3095                 rtm->rtm_type = RTN_UNICAST;
3096         rtm->rtm_flags = 0;
3097         if (!netif_carrier_ok(rt->dst.dev)) {
3098                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3099                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3100                         rtm->rtm_flags |= RTNH_F_DEAD;
3101         }
3102         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3103         rtm->rtm_protocol = rt->rt6i_protocol;
3104         if (rt->rt6i_flags & RTF_DYNAMIC)
3105                 rtm->rtm_protocol = RTPROT_REDIRECT;
3106         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3107                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3108                         rtm->rtm_protocol = RTPROT_RA;
3109                 else
3110                         rtm->rtm_protocol = RTPROT_KERNEL;
3111         }
3112
3113         if (rt->rt6i_flags & RTF_CACHE)
3114                 rtm->rtm_flags |= RTM_F_CLONED;
3115
3116         if (dst) {
3117                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3118                         goto nla_put_failure;
3119                 rtm->rtm_dst_len = 128;
3120         } else if (rtm->rtm_dst_len)
3121                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3122                         goto nla_put_failure;
3123 #ifdef CONFIG_IPV6_SUBTREES
3124         if (src) {
3125                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3126                         goto nla_put_failure;
3127                 rtm->rtm_src_len = 128;
3128         } else if (rtm->rtm_src_len &&
3129                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3130                 goto nla_put_failure;
3131 #endif
3132         if (iif) {
3133 #ifdef CONFIG_IPV6_MROUTE
3134                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3135                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3136                         if (err <= 0) {
3137                                 if (!nowait) {
3138                                         if (err == 0)
3139                                                 return 0;
3140                                         goto nla_put_failure;
3141                                 } else {
3142                                         if (err == -EMSGSIZE)
3143                                                 goto nla_put_failure;
3144                                 }
3145                         }
3146                 } else
3147 #endif
3148                         if (nla_put_u32(skb, RTA_IIF, iif))
3149                                 goto nla_put_failure;
3150         } else if (dst) {
3151                 struct in6_addr saddr_buf;
3152                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3153                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3154                         goto nla_put_failure;
3155         }
3156
3157         if (rt->rt6i_prefsrc.plen) {
3158                 struct in6_addr saddr_buf;
3159                 saddr_buf = rt->rt6i_prefsrc.addr;
3160                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3161                         goto nla_put_failure;
3162         }
3163
3164         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3165         if (rt->rt6i_pmtu)
3166                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3167         if (rtnetlink_put_metrics(skb, metrics) < 0)
3168                 goto nla_put_failure;
3169
3170         if (rt->rt6i_flags & RTF_GATEWAY) {
3171                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3172                         goto nla_put_failure;
3173         }
3174
3175         if (rt->dst.dev &&
3176             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3177                 goto nla_put_failure;
3178         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3179                 goto nla_put_failure;
3180
3181         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3182
3183         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3184                 goto nla_put_failure;
3185
3186         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3187                 goto nla_put_failure;
3188
3189         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3190
3191         nlmsg_end(skb, nlh);
3192         return 0;
3193
3194 nla_put_failure:
3195         nlmsg_cancel(skb, nlh);
3196         return -EMSGSIZE;
3197 }
3198
3199 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3200 {
3201         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3202         int prefix;
3203
3204         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3205                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3206                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3207         } else
3208                 prefix = 0;
3209
3210         return rt6_fill_node(arg->net,
3211                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3212                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3213                      prefix, 0, NLM_F_MULTI);
3214 }
3215
3216 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3217 {
3218         struct net *net = sock_net(in_skb->sk);
3219         struct nlattr *tb[RTA_MAX+1];
3220         struct rt6_info *rt;
3221         struct sk_buff *skb;
3222         struct rtmsg *rtm;
3223         struct flowi6 fl6;
3224         int err, iif = 0, oif = 0;
3225
3226         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3227         if (err < 0)
3228                 goto errout;
3229
3230         err = -EINVAL;
3231         memset(&fl6, 0, sizeof(fl6));
3232
3233         if (tb[RTA_SRC]) {
3234                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3235                         goto errout;
3236
3237                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3238         }
3239
3240         if (tb[RTA_DST]) {
3241                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3242                         goto errout;
3243
3244                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3245         }
3246
3247         if (tb[RTA_IIF])
3248                 iif = nla_get_u32(tb[RTA_IIF]);
3249
3250         if (tb[RTA_OIF])
3251                 oif = nla_get_u32(tb[RTA_OIF]);
3252
3253         if (tb[RTA_MARK])
3254                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3255
3256         if (iif) {
3257                 struct net_device *dev;
3258                 int flags = 0;
3259
3260                 dev = __dev_get_by_index(net, iif);
3261                 if (!dev) {
3262                         err = -ENODEV;
3263                         goto errout;
3264                 }
3265
3266                 fl6.flowi6_iif = iif;
3267
3268                 if (!ipv6_addr_any(&fl6.saddr))
3269                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3270
3271                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3272                                                                flags);
3273         } else {
3274                 fl6.flowi6_oif = oif;
3275
3276                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3277         }
3278
3279         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3280         if (!skb) {
3281                 ip6_rt_put(rt);
3282                 err = -ENOBUFS;
3283                 goto errout;
3284         }
3285
3286         /* Reserve room for dummy headers, this skb can pass
3287            through good chunk of routing engine.
3288          */
3289         skb_reset_mac_header(skb);
3290         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3291
3292         skb_dst_set(skb, &rt->dst);
3293
3294         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3295                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3296                             nlh->nlmsg_seq, 0, 0, 0);
3297         if (err < 0) {
3298                 kfree_skb(skb);
3299                 goto errout;
3300         }
3301
3302         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3303 errout:
3304         return err;
3305 }
3306
3307 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
3308 {
3309         struct sk_buff *skb;
3310         struct net *net = info->nl_net;
3311         u32 seq;
3312         int err;
3313
3314         err = -ENOBUFS;
3315         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3316
3317         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3318         if (!skb)
3319                 goto errout;
3320
3321         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3322                                 event, info->portid, seq, 0, 0, 0);
3323         if (err < 0) {
3324                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3325                 WARN_ON(err == -EMSGSIZE);
3326                 kfree_skb(skb);
3327                 goto errout;
3328         }
3329         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3330                     info->nlh, gfp_any());
3331         return;
3332 errout:
3333         if (err < 0)
3334                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3335 }
3336
3337 static int ip6_route_dev_notify(struct notifier_block *this,
3338                                 unsigned long event, void *ptr)
3339 {
3340         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3341         struct net *net = dev_net(dev);
3342
3343         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3344                 net->ipv6.ip6_null_entry->dst.dev = dev;
3345                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3346 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3347                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3348                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3349                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3350                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3351 #endif
3352         }
3353
3354         return NOTIFY_OK;
3355 }
3356
3357 /*
3358  *      /proc
3359  */
3360
3361 #ifdef CONFIG_PROC_FS
3362
3363 static const struct file_operations ipv6_route_proc_fops = {
3364         .owner          = THIS_MODULE,
3365         .open           = ipv6_route_open,
3366         .read           = seq_read,
3367         .llseek         = seq_lseek,
3368         .release        = seq_release_net,
3369 };
3370
3371 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3372 {
3373         struct net *net = (struct net *)seq->private;
3374         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3375                    net->ipv6.rt6_stats->fib_nodes,
3376                    net->ipv6.rt6_stats->fib_route_nodes,
3377                    net->ipv6.rt6_stats->fib_rt_alloc,
3378                    net->ipv6.rt6_stats->fib_rt_entries,
3379                    net->ipv6.rt6_stats->fib_rt_cache,
3380                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3381                    net->ipv6.rt6_stats->fib_discarded_routes);
3382
3383         return 0;
3384 }
3385
3386 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3387 {
3388         return single_open_net(inode, file, rt6_stats_seq_show);
3389 }
3390
3391 static const struct file_operations rt6_stats_seq_fops = {
3392         .owner   = THIS_MODULE,
3393         .open    = rt6_stats_seq_open,
3394         .read    = seq_read,
3395         .llseek  = seq_lseek,
3396         .release = single_release_net,
3397 };
3398 #endif  /* CONFIG_PROC_FS */
3399
3400 #ifdef CONFIG_SYSCTL
3401
3402 static
3403 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3404                               void __user *buffer, size_t *lenp, loff_t *ppos)
3405 {
3406         struct net *net;
3407         int delay;
3408         if (!write)
3409                 return -EINVAL;
3410
3411         net = (struct net *)ctl->extra1;
3412         delay = net->ipv6.sysctl.flush_delay;
3413         proc_dointvec(ctl, write, buffer, lenp, ppos);
3414         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3415         return 0;
3416 }
3417
3418 struct ctl_table ipv6_route_table_template[] = {
3419         {
3420                 .procname       =       "flush",
3421                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3422                 .maxlen         =       sizeof(int),
3423                 .mode           =       0200,
3424                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3425         },
3426         {
3427                 .procname       =       "gc_thresh",
3428                 .data           =       &ip6_dst_ops_template.gc_thresh,
3429                 .maxlen         =       sizeof(int),
3430                 .mode           =       0644,
3431                 .proc_handler   =       proc_dointvec,
3432         },
3433         {
3434                 .procname       =       "max_size",
3435                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3436                 .maxlen         =       sizeof(int),
3437                 .mode           =       0644,
3438                 .proc_handler   =       proc_dointvec,
3439         },
3440         {
3441                 .procname       =       "gc_min_interval",
3442                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3443                 .maxlen         =       sizeof(int),
3444                 .mode           =       0644,
3445                 .proc_handler   =       proc_dointvec_jiffies,
3446         },
3447         {
3448                 .procname       =       "gc_timeout",
3449                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3450                 .maxlen         =       sizeof(int),
3451                 .mode           =       0644,
3452                 .proc_handler   =       proc_dointvec_jiffies,
3453         },
3454         {
3455                 .procname       =       "gc_interval",
3456                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3457                 .maxlen         =       sizeof(int),
3458                 .mode           =       0644,
3459                 .proc_handler   =       proc_dointvec_jiffies,
3460         },
3461         {
3462                 .procname       =       "gc_elasticity",
3463                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3464                 .maxlen         =       sizeof(int),
3465                 .mode           =       0644,
3466                 .proc_handler   =       proc_dointvec,
3467         },
3468         {
3469                 .procname       =       "mtu_expires",
3470                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3471                 .maxlen         =       sizeof(int),
3472                 .mode           =       0644,
3473                 .proc_handler   =       proc_dointvec_jiffies,
3474         },
3475         {
3476                 .procname       =       "min_adv_mss",
3477                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3478                 .maxlen         =       sizeof(int),
3479                 .mode           =       0644,
3480                 .proc_handler   =       proc_dointvec,
3481         },
3482         {
3483                 .procname       =       "gc_min_interval_ms",
3484                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3485                 .maxlen         =       sizeof(int),
3486                 .mode           =       0644,
3487                 .proc_handler   =       proc_dointvec_ms_jiffies,
3488         },
3489         { }
3490 };
3491
3492 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3493 {
3494         struct ctl_table *table;
3495
3496         table = kmemdup(ipv6_route_table_template,
3497                         sizeof(ipv6_route_table_template),
3498                         GFP_KERNEL);
3499
3500         if (table) {
3501                 table[0].data = &net->ipv6.sysctl.flush_delay;
3502                 table[0].extra1 = net;
3503                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3504                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3505                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3506                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3507                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3508                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3509                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3510                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3511                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3512
3513                 /* Don't export sysctls to unprivileged users */
3514                 if (net->user_ns != &init_user_ns)
3515                         table[0].procname = NULL;
3516         }
3517
3518         return table;
3519 }
3520 #endif
3521
3522 static int __net_init ip6_route_net_init(struct net *net)
3523 {
3524         int ret = -ENOMEM;
3525
3526         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3527                sizeof(net->ipv6.ip6_dst_ops));
3528
3529         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3530                 goto out_ip6_dst_ops;
3531
3532         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3533                                            sizeof(*net->ipv6.ip6_null_entry),
3534                                            GFP_KERNEL);
3535         if (!net->ipv6.ip6_null_entry)
3536                 goto out_ip6_dst_entries;
3537         net->ipv6.ip6_null_entry->dst.path =
3538                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3539         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3540         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3541                          ip6_template_metrics, true);
3542
3543 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3544         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3545                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3546                                                GFP_KERNEL);
3547         if (!net->ipv6.ip6_prohibit_entry)
3548                 goto out_ip6_null_entry;
3549         net->ipv6.ip6_prohibit_entry->dst.path =
3550                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3551         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3552         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3553                          ip6_template_metrics, true);
3554
3555         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3556                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3557                                                GFP_KERNEL);
3558         if (!net->ipv6.ip6_blk_hole_entry)
3559                 goto out_ip6_prohibit_entry;
3560         net->ipv6.ip6_blk_hole_entry->dst.path =
3561                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3562         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3563         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3564                          ip6_template_metrics, true);
3565 #endif
3566
3567         net->ipv6.sysctl.flush_delay = 0;
3568         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3569         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3570         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3571         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3572         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3573         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3574         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3575
3576         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3577
3578         ret = 0;
3579 out:
3580         return ret;
3581
3582 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3583 out_ip6_prohibit_entry:
3584         kfree(net->ipv6.ip6_prohibit_entry);
3585 out_ip6_null_entry:
3586         kfree(net->ipv6.ip6_null_entry);
3587 #endif
3588 out_ip6_dst_entries:
3589         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3590 out_ip6_dst_ops:
3591         goto out;
3592 }
3593
3594 static void __net_exit ip6_route_net_exit(struct net *net)
3595 {
3596         kfree(net->ipv6.ip6_null_entry);
3597 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3598         kfree(net->ipv6.ip6_prohibit_entry);
3599         kfree(net->ipv6.ip6_blk_hole_entry);
3600 #endif
3601         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3602 }
3603
3604 static int __net_init ip6_route_net_init_late(struct net *net)
3605 {
3606 #ifdef CONFIG_PROC_FS
3607         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3608         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3609 #endif
3610         return 0;
3611 }
3612
3613 static void __net_exit ip6_route_net_exit_late(struct net *net)
3614 {
3615 #ifdef CONFIG_PROC_FS
3616         remove_proc_entry("ipv6_route", net->proc_net);
3617         remove_proc_entry("rt6_stats", net->proc_net);
3618 #endif
3619 }
3620
3621 static struct pernet_operations ip6_route_net_ops = {
3622         .init = ip6_route_net_init,
3623         .exit = ip6_route_net_exit,
3624 };
3625
3626 static int __net_init ipv6_inetpeer_init(struct net *net)
3627 {
3628         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3629
3630         if (!bp)
3631                 return -ENOMEM;
3632         inet_peer_base_init(bp);
3633         net->ipv6.peers = bp;
3634         return 0;
3635 }
3636
3637 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3638 {
3639         struct inet_peer_base *bp = net->ipv6.peers;
3640
3641         net->ipv6.peers = NULL;
3642         inetpeer_invalidate_tree(bp);
3643         kfree(bp);
3644 }
3645
3646 static struct pernet_operations ipv6_inetpeer_ops = {
3647         .init   =       ipv6_inetpeer_init,
3648         .exit   =       ipv6_inetpeer_exit,
3649 };
3650
3651 static struct pernet_operations ip6_route_net_late_ops = {
3652         .init = ip6_route_net_init_late,
3653         .exit = ip6_route_net_exit_late,
3654 };
3655
3656 static struct notifier_block ip6_route_dev_notifier = {
3657         .notifier_call = ip6_route_dev_notify,
3658         .priority = 0,
3659 };
3660
3661 int __init ip6_route_init(void)
3662 {
3663         int ret;
3664         int cpu;
3665
3666         ret = -ENOMEM;
3667         ip6_dst_ops_template.kmem_cachep =
3668                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3669                                   SLAB_HWCACHE_ALIGN, NULL);
3670         if (!ip6_dst_ops_template.kmem_cachep)
3671                 goto out;
3672
3673         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3674         if (ret)
3675                 goto out_kmem_cache;
3676
3677         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3678         if (ret)
3679                 goto out_dst_entries;
3680
3681         ret = register_pernet_subsys(&ip6_route_net_ops);
3682         if (ret)
3683                 goto out_register_inetpeer;
3684
3685         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3686
3687         /* Registering of the loopback is done before this portion of code,
3688          * the loopback reference in rt6_info will not be taken, do it
3689          * manually for init_net */
3690         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3691         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3692   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3693         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3694         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3695         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3696         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3697   #endif
3698         ret = fib6_init();
3699         if (ret)
3700                 goto out_register_subsys;
3701
3702         ret = xfrm6_init();
3703         if (ret)
3704                 goto out_fib6_init;
3705
3706         ret = fib6_rules_init();
3707         if (ret)
3708                 goto xfrm6_init;
3709
3710         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3711         if (ret)
3712                 goto fib6_rules_init;
3713
3714         ret = -ENOBUFS;
3715         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3716             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3717             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3718                 goto out_register_late_subsys;
3719
3720         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3721         if (ret)
3722                 goto out_register_late_subsys;
3723
3724         for_each_possible_cpu(cpu) {
3725                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3726
3727                 INIT_LIST_HEAD(&ul->head);
3728                 spin_lock_init(&ul->lock);
3729         }
3730
3731 out:
3732         return ret;
3733
3734 out_register_late_subsys:
3735         unregister_pernet_subsys(&ip6_route_net_late_ops);
3736 fib6_rules_init:
3737         fib6_rules_cleanup();
3738 xfrm6_init:
3739         xfrm6_fini();
3740 out_fib6_init:
3741         fib6_gc_cleanup();
3742 out_register_subsys:
3743         unregister_pernet_subsys(&ip6_route_net_ops);
3744 out_register_inetpeer:
3745         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3746 out_dst_entries:
3747         dst_entries_destroy(&ip6_dst_blackhole_ops);
3748 out_kmem_cache:
3749         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3750         goto out;
3751 }
3752
3753 void ip6_route_cleanup(void)
3754 {
3755         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3756         unregister_pernet_subsys(&ip6_route_net_late_ops);
3757         fib6_rules_cleanup();
3758         xfrm6_fini();
3759         fib6_gc_cleanup();
3760         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3761         unregister_pernet_subsys(&ip6_route_net_ops);
3762         dst_entries_destroy(&ip6_dst_blackhole_ops);
3763         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3764 }