net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64 #include <net/l3mdev.h>
  65
  66 #include <asm/uaccess.h>
  67
  68 #ifdef CONFIG_SYSCTL
  69 #include <linux/sysctl.h>
  70 #endif
  71
  72 enum rt6_nud_state {
  73         RT6_NUD_FAIL_HARD = -3,
  74         RT6_NUD_FAIL_PROBE = -2,
  75         RT6_NUD_FAIL_DO_RR = -1,
  76         RT6_NUD_SUCCEED = 1
  77 };
  78
  79 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  80 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  81 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  82 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  83 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  84 static void             ip6_dst_destroy(struct dst_entry *);
  85 static void             ip6_dst_ifdown(struct dst_entry *,
  86                                        struct net_device *dev, int how);
  87 static int               ip6_dst_gc(struct dst_ops *ops);
  88
  89 static int              ip6_pkt_discard(struct sk_buff *skb);
  90 static int              ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  91 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  92 static int              ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
  93 static void             ip6_link_failure(struct sk_buff *skb);
  94 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  95                                            struct sk_buff *skb, u32 mtu);
  96 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  97                                         struct sk_buff *skb);
  98 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
  99 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
 100
 101 #ifdef CONFIG_IPV6_ROUTE_INFO
 102 static struct rt6_info *rt6_add_route_info(struct net_device *dev,
 103                                            const struct in6_addr *prefix, int prefixlen,
 104                                            const struct in6_addr *gwaddr, unsigned int pref);
 105 static struct rt6_info *rt6_get_route_info(struct net_device *dev,
 106                                            const struct in6_addr *prefix, int prefixlen,
 107                                            const struct in6_addr *gwaddr);
 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         if (dev == loopback_dev)
 146                 return;
 147
 148         for_each_possible_cpu(cpu) {
 149                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 150                 struct rt6_info *rt;
 151
 152                 spin_lock_bh(&ul->lock);
 153                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 154                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 155                         struct net_device *rt_dev = rt->dst.dev;
 156
 157                         if (rt_idev->dev == dev) {
 158                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 159                                 in6_dev_put(rt_idev);
 160                         }
 161
 162                         if (rt_dev == dev) {
 163                                 rt->dst.dev = loopback_dev;
 164                                 dev_hold(rt->dst.dev);
 165                                 dev_put(rt_dev);
 166                         }
 167                 }
 168                 spin_unlock_bh(&ul->lock);
 169         }
 170 }
 171
 172 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 173 {
 174         return dst_metrics_write_ptr(rt->dst.from);
 175 }
 176
 177 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 178 {
 179         struct rt6_info *rt = (struct rt6_info *)dst;
 180
 181         if (rt->rt6i_flags & RTF_PCPU)
 182                 return rt6_pcpu_cow_metrics(rt);
 183         else if (rt->rt6i_flags & RTF_CACHE)
 184                 return NULL;
 185         else
 186                 return dst_cow_metrics_generic(dst, old);
 187 }
 188
 189 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 190                                              struct sk_buff *skb,
 191                                              const void *daddr)
 192 {
 193         struct in6_addr *p = &rt->rt6i_gateway;
 194
 195         if (!ipv6_addr_any(p))
 196                 return (const void *) p;
 197         else if (skb)
 198                 return &ipv6_hdr(skb)->daddr;
 199         return daddr;
 200 }
 201
 202 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 203                                           struct sk_buff *skb,
 204                                           const void *daddr)
 205 {
 206         struct rt6_info *rt = (struct rt6_info *) dst;
 207         struct neighbour *n;
 208
 209         daddr = choose_neigh_daddr(rt, skb, daddr);
 210         n = __ipv6_neigh_lookup(dst->dev, daddr);
 211         if (n)
 212                 return n;
 213         return neigh_create(&nd_tbl, daddr, dst->dev);
 214 }
 215
 216 static struct dst_ops ip6_dst_ops_template = {
 217         .family                 =       AF_INET6,
 218         .gc                     =       ip6_dst_gc,
 219         .gc_thresh              =       1024,
 220         .check                  =       ip6_dst_check,
 221         .default_advmss         =       ip6_default_advmss,
 222         .mtu                    =       ip6_mtu,
 223         .cow_metrics            =       ipv6_cow_metrics,
 224         .destroy                =       ip6_dst_destroy,
 225         .ifdown                 =       ip6_dst_ifdown,
 226         .negative_advice        =       ip6_negative_advice,
 227         .link_failure           =       ip6_link_failure,
 228         .update_pmtu            =       ip6_rt_update_pmtu,
 229         .redirect               =       rt6_do_redirect,
 230         .local_out              =       __ip6_local_out,
 231         .neigh_lookup           =       ip6_neigh_lookup,
 232 };
 233
 234 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 235 {
 236         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 237
 238         return mtu ? : dst->dev->mtu;
 239 }
 240
 241 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 242                                          struct sk_buff *skb, u32 mtu)
 243 {
 244 }
 245
 246 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 247                                       struct sk_buff *skb)
 248 {
 249 }
 250
 251 static struct dst_ops ip6_dst_blackhole_ops = {
 252         .family                 =       AF_INET6,
 253         .destroy                =       ip6_dst_destroy,
 254         .check                  =       ip6_dst_check,
 255         .mtu                    =       ip6_blackhole_mtu,
 256         .default_advmss         =       ip6_default_advmss,
 257         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 258         .redirect               =       ip6_rt_blackhole_redirect,
 259         .cow_metrics            =       dst_cow_metrics_generic,
 260         .neigh_lookup           =       ip6_neigh_lookup,
 261 };
 262
 263 static const u32 ip6_template_metrics[RTAX_MAX] = {
 264         [RTAX_HOPLIMIT - 1] = 0,
 265 };
 266
 267 static const struct rt6_info ip6_null_entry_template = {
 268         .dst = {
 269                 .__refcnt       = ATOMIC_INIT(1),
 270                 .__use          = 1,
 271                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 272                 .error          = -ENETUNREACH,
 273                 .input          = ip6_pkt_discard,
 274                 .output         = ip6_pkt_discard_out,
 275         },
 276         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 277         .rt6i_protocol  = RTPROT_KERNEL,
 278         .rt6i_metric    = ~(u32) 0,
 279         .rt6i_ref       = ATOMIC_INIT(1),
 280 };
 281
 282 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 283
 284 static const struct rt6_info ip6_prohibit_entry_template = {
 285         .dst = {
 286                 .__refcnt       = ATOMIC_INIT(1),
 287                 .__use          = 1,
 288                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 289                 .error          = -EACCES,
 290                 .input          = ip6_pkt_prohibit,
 291                 .output         = ip6_pkt_prohibit_out,
 292         },
 293         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 294         .rt6i_protocol  = RTPROT_KERNEL,
 295         .rt6i_metric    = ~(u32) 0,
 296         .rt6i_ref       = ATOMIC_INIT(1),
 297 };
 298
 299 static const struct rt6_info ip6_blk_hole_entry_template = {
 300         .dst = {
 301                 .__refcnt       = ATOMIC_INIT(1),
 302                 .__use          = 1,
 303                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 304                 .error          = -EINVAL,
 305                 .input          = dst_discard,
 306                 .output         = dst_discard_out,
 307         },
 308         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 309         .rt6i_protocol  = RTPROT_KERNEL,
 310         .rt6i_metric    = ~(u32) 0,
 311         .rt6i_ref       = ATOMIC_INIT(1),
 312 };
 313
 314 #endif
 315
 316 static void rt6_info_init(struct rt6_info *rt)
 317 {
 318         struct dst_entry *dst = &rt->dst;
 319
 320         memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 321         INIT_LIST_HEAD(&rt->rt6i_siblings);
 322         INIT_LIST_HEAD(&rt->rt6i_uncached);
 323 }
 324
 325 /* allocate dst with ip6_dst_ops */
 326 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 327                                         struct net_device *dev,
 328                                         int flags)
 329 {
 330         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 331                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 332
 333         if (rt)
 334                 rt6_info_init(rt);
 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                 return time_after(jiffies, rt->dst.expires);
 410         else
 411                 return false;
 412 }
 413
 414 static bool rt6_check_expired(const struct rt6_info *rt)
 415 {
 416         if (rt->rt6i_flags & RTF_EXPIRES) {
 417                 if (time_after(jiffies, rt->dst.expires))
 418                         return true;
 419         } else if (rt->dst.from) {
 420                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 421         }
 422         return false;
 423 }
 424
 425 /* Multipath route selection:
 426  *   Hash based function using packet header and flowlabel.
 427  * Adapted from fib_info_hashfn()
 428  */
 429 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 430                                const struct flowi6 *fl6)
 431 {
 432         return get_hash_from_flowi6(fl6) % candidate_count;
 433 }
 434
 435 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 436                                              struct flowi6 *fl6, int oif,
 437                                              int strict)
 438 {
 439         struct rt6_info *sibling, *next_sibling;
 440         int route_choosen;
 441
 442         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 443         /* Don't change the route, if route_choosen == 0
 444          * (siblings does not include ourself)
 445          */
 446         if (route_choosen)
 447                 list_for_each_entry_safe(sibling, next_sibling,
 448                                 &match->rt6i_siblings, rt6i_siblings) {
 449                         route_choosen--;
 450                         if (route_choosen == 0) {
 451                                 if (rt6_score_route(sibling, oif, strict) < 0)
 452                                         break;
 453                                 match = sibling;
 454                                 break;
 455                         }
 456                 }
 457         return match;
 458 }
 459
 460 /*
 461  *      Route lookup. Any table->tb6_lock is implied.
 462  */
 463
 464 static inline struct rt6_info *rt6_device_match(struct net *net,
 465                                                     struct rt6_info *rt,
 466                                                     const struct in6_addr *saddr,
 467                                                     int oif,
 468                                                     int flags)
 469 {
 470         struct rt6_info *local = NULL;
 471         struct rt6_info *sprt;
 472
 473         if (!oif && ipv6_addr_any(saddr))
 474                 goto out;
 475
 476         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 477                 struct net_device *dev = sprt->dst.dev;
 478
 479                 if (oif) {
 480                         if (dev->ifindex == oif)
 481                                 return sprt;
 482                         if (dev->flags & IFF_LOOPBACK) {
 483                                 if (!sprt->rt6i_idev ||
 484                                     sprt->rt6i_idev->dev->ifindex != oif) {
 485                                         if (flags & RT6_LOOKUP_F_IFACE)
 486                                                 continue;
 487                                         if (local &&
 488                                             local->rt6i_idev->dev->ifindex == oif)
 489                                                 continue;
 490                                 }
 491                                 local = sprt;
 492                         }
 493                 } else {
 494                         if (ipv6_chk_addr(net, saddr, dev,
 495                                           flags & RT6_LOOKUP_F_IFACE))
 496                                 return sprt;
 497                 }
 498         }
 499
 500         if (oif) {
 501                 if (local)
 502                         return local;
 503
 504                 if (flags & RT6_LOOKUP_F_IFACE)
 505                         return net->ipv6.ip6_null_entry;
 506         }
 507 out:
 508         return rt;
 509 }
 510
 511 #ifdef CONFIG_IPV6_ROUTER_PREF
 512 struct __rt6_probe_work {
 513         struct work_struct work;
 514         struct in6_addr target;
 515         struct net_device *dev;
 516 };
 517
 518 static void rt6_probe_deferred(struct work_struct *w)
 519 {
 520         struct in6_addr mcaddr;
 521         struct __rt6_probe_work *work =
 522                 container_of(w, struct __rt6_probe_work, work);
 523
 524         addrconf_addr_solict_mult(&work->target, &mcaddr);
 525         ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL);
 526         dev_put(work->dev);
 527         kfree(work);
 528 }
 529
 530 static void rt6_probe(struct rt6_info *rt)
 531 {
 532         struct __rt6_probe_work *work;
 533         struct neighbour *neigh;
 534         /*
 535          * Okay, this does not seem to be appropriate
 536          * for now, however, we need to check if it
 537          * is really so; aka Router Reachability Probing.
 538          *
 539          * Router Reachability Probe MUST be rate-limited
 540          * to no more than one per minute.
 541          */
 542         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 543                 return;
 544         rcu_read_lock_bh();
 545         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 546         if (neigh) {
 547                 if (neigh->nud_state & NUD_VALID)
 548                         goto out;
 549
 550                 work = NULL;
 551                 write_lock(&neigh->lock);
 552                 if (!(neigh->nud_state & NUD_VALID) &&
 553                     time_after(jiffies,
 554                                neigh->updated +
 555                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 556                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 557                         if (work)
 558                                 __neigh_set_probe_once(neigh);
 559                 }
 560                 write_unlock(&neigh->lock);
 561         } else {
 562                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 563         }
 564
 565         if (work) {
 566                 INIT_WORK(&work->work, rt6_probe_deferred);
 567                 work->target = rt->rt6i_gateway;
 568                 dev_hold(rt->dst.dev);
 569                 work->dev = rt->dst.dev;
 570                 schedule_work(&work->work);
 571         }
 572
 573 out:
 574         rcu_read_unlock_bh();
 575 }
 576 #else
 577 static inline void rt6_probe(struct rt6_info *rt)
 578 {
 579 }
 580 #endif
 581
 582 /*
 583  * Default Router Selection (RFC 2461 6.3.6)
 584  */
 585 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 586 {
 587         struct net_device *dev = rt->dst.dev;
 588         if (!oif || dev->ifindex == oif)
 589                 return 2;
 590         if ((dev->flags & IFF_LOOPBACK) &&
 591             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 592                 return 1;
 593         return 0;
 594 }
 595
 596 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 597 {
 598         struct neighbour *neigh;
 599         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 600
 601         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 602             !(rt->rt6i_flags & RTF_GATEWAY))
 603                 return RT6_NUD_SUCCEED;
 604
 605         rcu_read_lock_bh();
 606         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 607         if (neigh) {
 608                 read_lock(&neigh->lock);
 609                 if (neigh->nud_state & NUD_VALID)
 610                         ret = RT6_NUD_SUCCEED;
 611 #ifdef CONFIG_IPV6_ROUTER_PREF
 612                 else if (!(neigh->nud_state & NUD_FAILED))
 613                         ret = RT6_NUD_SUCCEED;
 614                 else
 615                         ret = RT6_NUD_FAIL_PROBE;
 616 #endif
 617                 read_unlock(&neigh->lock);
 618         } else {
 619                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 620                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 621         }
 622         rcu_read_unlock_bh();
 623
 624         return ret;
 625 }
 626
 627 static int rt6_score_route(struct rt6_info *rt, int oif,
 628                            int strict)
 629 {
 630         int m;
 631
 632         m = rt6_check_dev(rt, oif);
 633         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 634                 return RT6_NUD_FAIL_HARD;
 635 #ifdef CONFIG_IPV6_ROUTER_PREF
 636         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 637 #endif
 638         if (strict & RT6_LOOKUP_F_REACHABLE) {
 639                 int n = rt6_check_neigh(rt);
 640                 if (n < 0)
 641                         return n;
 642         }
 643         return m;
 644 }
 645
 646 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 647                                    int *mpri, struct rt6_info *match,
 648                                    bool *do_rr)
 649 {
 650         int m;
 651         bool match_do_rr = false;
 652         struct inet6_dev *idev = rt->rt6i_idev;
 653         struct net_device *dev = rt->dst.dev;
 654
 655         if (dev && !netif_carrier_ok(dev) &&
 656             idev->cnf.ignore_routes_with_linkdown)
 657                 goto out;
 658
 659         if (rt6_check_expired(rt))
 660                 goto out;
 661
 662         m = rt6_score_route(rt, oif, strict);
 663         if (m == RT6_NUD_FAIL_DO_RR) {
 664                 match_do_rr = true;
 665                 m = 0; /* lowest valid score */
 666         } else if (m == RT6_NUD_FAIL_HARD) {
 667                 goto out;
 668         }
 669
 670         if (strict & RT6_LOOKUP_F_REACHABLE)
 671                 rt6_probe(rt);
 672
 673         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 674         if (m > *mpri) {
 675                 *do_rr = match_do_rr;
 676                 *mpri = m;
 677                 match = rt;
 678         }
 679 out:
 680         return match;
 681 }
 682
 683 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 684                                      struct rt6_info *rr_head,
 685                                      u32 metric, int oif, int strict,
 686                                      bool *do_rr)
 687 {
 688         struct rt6_info *rt, *match, *cont;
 689         int mpri = -1;
 690
 691         match = NULL;
 692         cont = NULL;
 693         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 694                 if (rt->rt6i_metric != metric) {
 695                         cont = rt;
 696                         break;
 697                 }
 698
 699                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 700         }
 701
 702         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 703                 if (rt->rt6i_metric != metric) {
 704                         cont = rt;
 705                         break;
 706                 }
 707
 708                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 709         }
 710
 711         if (match || !cont)
 712                 return match;
 713
 714         for (rt = cont; rt; rt = rt->dst.rt6_next)
 715                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 716
 717         return match;
 718 }
 719
 720 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 721 {
 722         struct rt6_info *match, *rt0;
 723         struct net *net;
 724         bool do_rr = false;
 725
 726         rt0 = fn->rr_ptr;
 727         if (!rt0)
 728                 fn->rr_ptr = rt0 = fn->leaf;
 729
 730         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 731                              &do_rr);
 732
 733         if (do_rr) {
 734                 struct rt6_info *next = rt0->dst.rt6_next;
 735
 736                 /* no entries matched; do round-robin */
 737                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 738                         next = fn->leaf;
 739
 740                 if (next != rt0)
 741                         fn->rr_ptr = next;
 742         }
 743
 744         net = dev_net(rt0->dst.dev);
 745         return match ? match : net->ipv6.ip6_null_entry;
 746 }
 747
 748 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 749 {
 750         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 751 }
 752
 753 #ifdef CONFIG_IPV6_ROUTE_INFO
 754 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 755                   const struct in6_addr *gwaddr)
 756 {
 757         struct route_info *rinfo = (struct route_info *) opt;
 758         struct in6_addr prefix_buf, *prefix;
 759         unsigned int pref;
 760         unsigned long lifetime;
 761         struct rt6_info *rt;
 762
 763         if (len < sizeof(struct route_info)) {
 764                 return -EINVAL;
 765         }
 766
 767         /* Sanity check for prefix_len and length */
 768         if (rinfo->length > 3) {
 769                 return -EINVAL;
 770         } else if (rinfo->prefix_len > 128) {
 771                 return -EINVAL;
 772         } else if (rinfo->prefix_len > 64) {
 773                 if (rinfo->length < 2) {
 774                         return -EINVAL;
 775                 }
 776         } else if (rinfo->prefix_len > 0) {
 777                 if (rinfo->length < 1) {
 778                         return -EINVAL;
 779                 }
 780         }
 781
 782         pref = rinfo->route_pref;
 783         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 784                 return -EINVAL;
 785
 786         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 787
 788         if (rinfo->length == 3)
 789                 prefix = (struct in6_addr *)rinfo->prefix;
 790         else {
 791                 /* this function is safe */
 792                 ipv6_addr_prefix(&prefix_buf,
 793                                  (struct in6_addr *)rinfo->prefix,
 794                                  rinfo->prefix_len);
 795                 prefix = &prefix_buf;
 796         }
 797
 798         if (rinfo->prefix_len == 0)
 799                 rt = rt6_get_dflt_router(gwaddr, dev);
 800         else
 801                 rt = rt6_get_route_info(dev, prefix, rinfo->prefix_len, gwaddr);
 802
 803         if (rt && !lifetime) {
 804                 ip6_del_rt(rt);
 805                 rt = NULL;
 806         }
 807
 808         if (!rt && lifetime)
 809                 rt = rt6_add_route_info(dev, prefix, rinfo->prefix_len, gwaddr, pref);
 810         else if (rt)
 811                 rt->rt6i_flags = RTF_ROUTEINFO |
 812                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 813
 814         if (rt) {
 815                 if (!addrconf_finite_timeout(lifetime))
 816                         rt6_clean_expires(rt);
 817                 else
 818                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 819
 820                 ip6_rt_put(rt);
 821         }
 822         return 0;
 823 }
 824 #endif
 825
 826 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 827                                         struct in6_addr *saddr)
 828 {
 829         struct fib6_node *pn;
 830         while (1) {
 831                 if (fn->fn_flags & RTN_TL_ROOT)
 832                         return NULL;
 833                 pn = fn->parent;
 834                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 835                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 836                 else
 837                         fn = pn;
 838                 if (fn->fn_flags & RTN_RTINFO)
 839                         return fn;
 840         }
 841 }
 842
 843 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 844                                              struct fib6_table *table,
 845                                              struct flowi6 *fl6, int flags)
 846 {
 847         struct fib6_node *fn;
 848         struct rt6_info *rt;
 849
 850         read_lock_bh(&table->tb6_lock);
 851         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 852 restart:
 853         rt = fn->leaf;
 854         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 855         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 856                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 857         if (rt == net->ipv6.ip6_null_entry) {
 858                 fn = fib6_backtrack(fn, &fl6->saddr);
 859                 if (fn)
 860                         goto restart;
 861         }
 862         dst_use(&rt->dst, jiffies);
 863         read_unlock_bh(&table->tb6_lock);
 864         return rt;
 865
 866 }
 867
 868 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 869                                     int flags)
 870 {
 871         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 872 }
 873 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 874
 875 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 876                             const struct in6_addr *saddr, int oif, int strict)
 877 {
 878         struct flowi6 fl6 = {
 879                 .flowi6_oif = oif,
 880                 .daddr = *daddr,
 881         };
 882         struct dst_entry *dst;
 883         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 884
 885         if (saddr) {
 886                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 887                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 888         }
 889
 890         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 891         if (dst->error == 0)
 892                 return (struct rt6_info *) dst;
 893
 894         dst_release(dst);
 895
 896         return NULL;
 897 }
 898 EXPORT_SYMBOL(rt6_lookup);
 899
 900 /* ip6_ins_rt is called with FREE table->tb6_lock.
 901    It takes new route entry, the addition fails by any reason the
 902    route is freed. In any case, if caller does not hold it, it may
 903    be destroyed.
 904  */
 905
 906 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 907                         struct mx6_config *mxc)
 908 {
 909         int err;
 910         struct fib6_table *table;
 911
 912         table = rt->rt6i_table;
 913         write_lock_bh(&table->tb6_lock);
 914         err = fib6_add(&table->tb6_root, rt, info, mxc);
 915         write_unlock_bh(&table->tb6_lock);
 916
 917         return err;
 918 }
 919
 920 int ip6_ins_rt(struct rt6_info *rt)
 921 {
 922         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 923         struct mx6_config mxc = { .mx = NULL, };
 924
 925         return __ip6_ins_rt(rt, &info, &mxc);
 926 }
 927
 928 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 929                                            const struct in6_addr *daddr,
 930                                            const struct in6_addr *saddr)
 931 {
 932         struct rt6_info *rt;
 933
 934         /*
 935          *      Clone the route.
 936          */
 937
 938         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 939                 ort = (struct rt6_info *)ort->dst.from;
 940
 941         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 942
 943         if (!rt)
 944                 return NULL;
 945
 946         ip6_rt_copy_init(rt, ort);
 947         rt->rt6i_flags |= RTF_CACHE;
 948         rt->rt6i_metric = 0;
 949         rt->dst.flags |= DST_HOST;
 950         rt->rt6i_dst.addr = *daddr;
 951         rt->rt6i_dst.plen = 128;
 952
 953         if (!rt6_is_gw_or_nonexthop(ort)) {
 954                 if (ort->rt6i_dst.plen != 128 &&
 955                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 956                         rt->rt6i_flags |= RTF_ANYCAST;
 957 #ifdef CONFIG_IPV6_SUBTREES
 958                 if (rt->rt6i_src.plen && saddr) {
 959                         rt->rt6i_src.addr = *saddr;
 960                         rt->rt6i_src.plen = 128;
 961                 }
 962 #endif
 963         }
 964
 965         return rt;
 966 }
 967
 968 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 969 {
 970         struct rt6_info *pcpu_rt;
 971
 972         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 973                                   rt->dst.dev, rt->dst.flags);
 974
 975         if (!pcpu_rt)
 976                 return NULL;
 977         ip6_rt_copy_init(pcpu_rt, rt);
 978         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 979         pcpu_rt->rt6i_flags |= RTF_PCPU;
 980         return pcpu_rt;
 981 }
 982
 983 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 984 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 985 {
 986         struct rt6_info *pcpu_rt, **p;
 987
 988         p = this_cpu_ptr(rt->rt6i_pcpu);
 989         pcpu_rt = *p;
 990
 991         if (pcpu_rt) {
 992                 dst_hold(&pcpu_rt->dst);
 993                 rt6_dst_from_metrics_check(pcpu_rt);
 994         }
 995         return pcpu_rt;
 996 }
 997
 998 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
 999 {
1000         struct fib6_table *table = rt->rt6i_table;
1001         struct rt6_info *pcpu_rt, *prev, **p;
1002
1003         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1004         if (!pcpu_rt) {
1005                 struct net *net = dev_net(rt->dst.dev);
1006
1007                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1008                 return net->ipv6.ip6_null_entry;
1009         }
1010
1011         read_lock_bh(&table->tb6_lock);
1012         if (rt->rt6i_pcpu) {
1013                 p = this_cpu_ptr(rt->rt6i_pcpu);
1014                 prev = cmpxchg(p, NULL, pcpu_rt);
1015                 if (prev) {
1016                         /* If someone did it before us, return prev instead */
1017                         dst_destroy(&pcpu_rt->dst);
1018                         pcpu_rt = prev;
1019                 }
1020         } else {
1021                 /* rt has been removed from the fib6 tree
1022                  * before we have a chance to acquire the read_lock.
1023                  * In this case, don't brother to create a pcpu rt
1024                  * since rt is going away anyway.  The next
1025                  * dst_check() will trigger a re-lookup.
1026                  */
1027                 dst_destroy(&pcpu_rt->dst);
1028                 pcpu_rt = rt;
1029         }
1030         dst_hold(&pcpu_rt->dst);
1031         rt6_dst_from_metrics_check(pcpu_rt);
1032         read_unlock_bh(&table->tb6_lock);
1033         return pcpu_rt;
1034 }
1035
1036 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1037                                       struct flowi6 *fl6, int flags)
1038 {
1039         struct fib6_node *fn, *saved_fn;
1040         struct rt6_info *rt;
1041         int strict = 0;
1042
1043         strict |= flags & RT6_LOOKUP_F_IFACE;
1044         if (net->ipv6.devconf_all->forwarding == 0)
1045                 strict |= RT6_LOOKUP_F_REACHABLE;
1046
1047         read_lock_bh(&table->tb6_lock);
1048
1049         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1050         saved_fn = fn;
1051
1052         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1053                 oif = 0;
1054
1055 redo_rt6_select:
1056         rt = rt6_select(fn, oif, strict);
1057         if (rt->rt6i_nsiblings)
1058                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1059         if (rt == net->ipv6.ip6_null_entry) {
1060                 fn = fib6_backtrack(fn, &fl6->saddr);
1061                 if (fn)
1062                         goto redo_rt6_select;
1063                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1064                         /* also consider unreachable route */
1065                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1066                         fn = saved_fn;
1067                         goto redo_rt6_select;
1068                 }
1069         }
1070
1071
1072         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1073                 dst_use(&rt->dst, jiffies);
1074                 read_unlock_bh(&table->tb6_lock);
1075
1076                 rt6_dst_from_metrics_check(rt);
1077                 return rt;
1078         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1079                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1080                 /* Create a RTF_CACHE clone which will not be
1081                  * owned by the fib6 tree.  It is for the special case where
1082                  * the daddr in the skb during the neighbor look-up is different
1083                  * from the fl6->daddr used to look-up route here.
1084                  */
1085
1086                 struct rt6_info *uncached_rt;
1087
1088                 dst_use(&rt->dst, jiffies);
1089                 read_unlock_bh(&table->tb6_lock);
1090
1091                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1092                 dst_release(&rt->dst);
1093
1094                 if (uncached_rt)
1095                         rt6_uncached_list_add(uncached_rt);
1096                 else
1097                         uncached_rt = net->ipv6.ip6_null_entry;
1098
1099                 dst_hold(&uncached_rt->dst);
1100                 return uncached_rt;
1101
1102         } else {
1103                 /* Get a percpu copy */
1104
1105                 struct rt6_info *pcpu_rt;
1106
1107                 rt->dst.lastuse = jiffies;
1108                 rt->dst.__use++;
1109                 pcpu_rt = rt6_get_pcpu_route(rt);
1110
1111                 if (pcpu_rt) {
1112                         read_unlock_bh(&table->tb6_lock);
1113                 } else {
1114                         /* We have to do the read_unlock first
1115                          * because rt6_make_pcpu_route() may trigger
1116                          * ip6_dst_gc() which will take the write_lock.
1117                          */
1118                         dst_hold(&rt->dst);
1119                         read_unlock_bh(&table->tb6_lock);
1120                         pcpu_rt = rt6_make_pcpu_route(rt);
1121                         dst_release(&rt->dst);
1122                 }
1123
1124                 return pcpu_rt;
1125
1126         }
1127 }
1128
1129 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1130                                             struct flowi6 *fl6, int flags)
1131 {
1132         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1133 }
1134
1135 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1136                                                 struct net_device *dev,
1137                                                 struct flowi6 *fl6, int flags)
1138 {
1139         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1140                 flags |= RT6_LOOKUP_F_IFACE;
1141
1142         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1143 }
1144
1145 void ip6_route_input(struct sk_buff *skb)
1146 {
1147         const struct ipv6hdr *iph = ipv6_hdr(skb);
1148         struct net *net = dev_net(skb->dev);
1149         int flags = RT6_LOOKUP_F_HAS_SADDR;
1150         struct ip_tunnel_info *tun_info;
1151         struct flowi6 fl6 = {
1152                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1153                 .daddr = iph->daddr,
1154                 .saddr = iph->saddr,
1155                 .flowlabel = ip6_flowinfo(iph),
1156                 .flowi6_mark = skb->mark,
1157                 .flowi6_proto = iph->nexthdr,
1158         };
1159
1160         tun_info = skb_tunnel_info(skb);
1161         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1162                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1163         skb_dst_drop(skb);
1164         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1165 }
1166
1167 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1168                                              struct flowi6 *fl6, int flags)
1169 {
1170         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1171 }
1172
1173 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1174                                     struct flowi6 *fl6)
1175 {
1176         struct dst_entry *dst;
1177         int flags = 0;
1178         bool any_src;
1179
1180         dst = l3mdev_rt6_dst_by_oif(net, fl6);
1181         if (dst)
1182                 return dst;
1183
1184         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1185
1186         any_src = ipv6_addr_any(&fl6->saddr);
1187         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1188             (fl6->flowi6_oif && any_src))
1189                 flags |= RT6_LOOKUP_F_IFACE;
1190
1191         if (!any_src)
1192                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1193         else if (sk)
1194                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1195
1196         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1197 }
1198 EXPORT_SYMBOL(ip6_route_output);
1199
1200 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1201 {
1202         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1203         struct dst_entry *new = NULL;
1204
1205         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1206         if (rt) {
1207                 rt6_info_init(rt);
1208
1209                 new = &rt->dst;
1210                 new->__use = 1;
1211                 new->input = dst_discard;
1212                 new->output = dst_discard_out;
1213
1214                 dst_copy_metrics(new, &ort->dst);
1215                 rt->rt6i_idev = ort->rt6i_idev;
1216                 if (rt->rt6i_idev)
1217                         in6_dev_hold(rt->rt6i_idev);
1218
1219                 rt->rt6i_gateway = ort->rt6i_gateway;
1220                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1221                 rt->rt6i_metric = 0;
1222
1223                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1224 #ifdef CONFIG_IPV6_SUBTREES
1225                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1226 #endif
1227
1228                 dst_free(new);
1229         }
1230
1231         dst_release(dst_orig);
1232         return new ? new : ERR_PTR(-ENOMEM);
1233 }
1234
1235 /*
1236  *      Destination cache support functions
1237  */
1238
1239 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1240 {
1241         if (rt->dst.from &&
1242             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1243                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1244 }
1245
1246 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1247 {
1248         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1249                 return NULL;
1250
1251         if (rt6_check_expired(rt))
1252                 return NULL;
1253
1254         return &rt->dst;
1255 }
1256
1257 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1258 {
1259         if (!__rt6_check_expired(rt) &&
1260             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1261             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1262                 return &rt->dst;
1263         else
1264                 return NULL;
1265 }
1266
1267 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1268 {
1269         struct rt6_info *rt;
1270
1271         rt = (struct rt6_info *) dst;
1272
1273         /* All IPV6 dsts are created with ->obsolete set to the value
1274          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1275          * into this function always.
1276          */
1277
1278         rt6_dst_from_metrics_check(rt);
1279
1280         if (rt->rt6i_flags & RTF_PCPU ||
1281             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1282                 return rt6_dst_from_check(rt, cookie);
1283         else
1284                 return rt6_check(rt, cookie);
1285 }
1286
1287 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1288 {
1289         struct rt6_info *rt = (struct rt6_info *) dst;
1290
1291         if (rt) {
1292                 if (rt->rt6i_flags & RTF_CACHE) {
1293                         if (rt6_check_expired(rt)) {
1294                                 ip6_del_rt(rt);
1295                                 dst = NULL;
1296                         }
1297                 } else {
1298                         dst_release(dst);
1299                         dst = NULL;
1300                 }
1301         }
1302         return dst;
1303 }
1304
1305 static void ip6_link_failure(struct sk_buff *skb)
1306 {
1307         struct rt6_info *rt;
1308
1309         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1310
1311         rt = (struct rt6_info *) skb_dst(skb);
1312         if (rt) {
1313                 if (rt->rt6i_flags & RTF_CACHE) {
1314                         dst_hold(&rt->dst);
1315                         ip6_del_rt(rt);
1316                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1317                         rt->rt6i_node->fn_sernum = -1;
1318                 }
1319         }
1320 }
1321
1322 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1323 {
1324         struct net *net = dev_net(rt->dst.dev);
1325
1326         rt->rt6i_flags |= RTF_MODIFIED;
1327         rt->rt6i_pmtu = mtu;
1328         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1329 }
1330
1331 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1332 {
1333         return !(rt->rt6i_flags & RTF_CACHE) &&
1334                 (rt->rt6i_flags & RTF_PCPU || rt->rt6i_node);
1335 }
1336
1337 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1338                                  const struct ipv6hdr *iph, u32 mtu)
1339 {
1340         struct rt6_info *rt6 = (struct rt6_info *)dst;
1341
1342         if (rt6->rt6i_flags & RTF_LOCAL)
1343                 return;
1344
1345         dst_confirm(dst);
1346         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1347         if (mtu >= dst_mtu(dst))
1348                 return;
1349
1350         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1351                 rt6_do_update_pmtu(rt6, mtu);
1352         } else {
1353                 const struct in6_addr *daddr, *saddr;
1354                 struct rt6_info *nrt6;
1355
1356                 if (iph) {
1357                         daddr = &iph->daddr;
1358                         saddr = &iph->saddr;
1359                 } else if (sk) {
1360                         daddr = &sk->sk_v6_daddr;
1361                         saddr = &inet6_sk(sk)->saddr;
1362                 } else {
1363                         return;
1364                 }
1365                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1366                 if (nrt6) {
1367                         rt6_do_update_pmtu(nrt6, mtu);
1368
1369                         /* ip6_ins_rt(nrt6) will bump the
1370                          * rt6->rt6i_node->fn_sernum
1371                          * which will fail the next rt6_check() and
1372                          * invalidate the sk->sk_dst_cache.
1373                          */
1374                         ip6_ins_rt(nrt6);
1375                 }
1376         }
1377 }
1378
1379 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1380                                struct sk_buff *skb, u32 mtu)
1381 {
1382         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1383 }
1384
1385 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1386                      int oif, u32 mark)
1387 {
1388         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1389         struct dst_entry *dst;
1390         struct flowi6 fl6;
1391
1392         memset(&fl6, 0, sizeof(fl6));
1393         fl6.flowi6_oif = oif;
1394         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1395         fl6.daddr = iph->daddr;
1396         fl6.saddr = iph->saddr;
1397         fl6.flowlabel = ip6_flowinfo(iph);
1398
1399         dst = ip6_route_output(net, NULL, &fl6);
1400         if (!dst->error)
1401                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1402         dst_release(dst);
1403 }
1404 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1405
1406 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1407 {
1408         ip6_update_pmtu(skb, sock_net(sk), mtu,
1409                         sk->sk_bound_dev_if, sk->sk_mark);
1410 }
1411 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1412
1413 /* Handle redirects */
1414 struct ip6rd_flowi {
1415         struct flowi6 fl6;
1416         struct in6_addr gateway;
1417 };
1418
1419 static struct rt6_info *__ip6_route_redirect(struct net *net,
1420                                              struct fib6_table *table,
1421                                              struct flowi6 *fl6,
1422                                              int flags)
1423 {
1424         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1425         struct rt6_info *rt;
1426         struct fib6_node *fn;
1427
1428         /* Get the "current" route for this destination and
1429          * check if the redirect has come from approriate router.
1430          *
1431          * RFC 4861 specifies that redirects should only be
1432          * accepted if they come from the nexthop to the target.
1433          * Due to the way the routes are chosen, this notion
1434          * is a bit fuzzy and one might need to check all possible
1435          * routes.
1436          */
1437
1438         read_lock_bh(&table->tb6_lock);
1439         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1440 restart:
1441         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1442                 if (rt6_check_expired(rt))
1443                         continue;
1444                 if (rt->dst.error)
1445                         break;
1446                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1447                         continue;
1448                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1449                         continue;
1450                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1451                         continue;
1452                 break;
1453         }
1454
1455         if (!rt)
1456                 rt = net->ipv6.ip6_null_entry;
1457         else if (rt->dst.error) {
1458                 rt = net->ipv6.ip6_null_entry;
1459                 goto out;
1460         }
1461
1462         if (rt == net->ipv6.ip6_null_entry) {
1463                 fn = fib6_backtrack(fn, &fl6->saddr);
1464                 if (fn)
1465                         goto restart;
1466         }
1467
1468 out:
1469         dst_hold(&rt->dst);
1470
1471         read_unlock_bh(&table->tb6_lock);
1472
1473         return rt;
1474 };
1475
1476 static struct dst_entry *ip6_route_redirect(struct net *net,
1477                                         const struct flowi6 *fl6,
1478                                         const struct in6_addr *gateway)
1479 {
1480         int flags = RT6_LOOKUP_F_HAS_SADDR;
1481         struct ip6rd_flowi rdfl;
1482
1483         rdfl.fl6 = *fl6;
1484         rdfl.gateway = *gateway;
1485
1486         return fib6_rule_lookup(net, &rdfl.fl6,
1487                                 flags, __ip6_route_redirect);
1488 }
1489
1490 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1491 {
1492         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1493         struct dst_entry *dst;
1494         struct flowi6 fl6;
1495
1496         memset(&fl6, 0, sizeof(fl6));
1497         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1498         fl6.flowi6_oif = oif;
1499         fl6.flowi6_mark = mark;
1500         fl6.daddr = iph->daddr;
1501         fl6.saddr = iph->saddr;
1502         fl6.flowlabel = ip6_flowinfo(iph);
1503
1504         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1505         rt6_do_redirect(dst, NULL, skb);
1506         dst_release(dst);
1507 }
1508 EXPORT_SYMBOL_GPL(ip6_redirect);
1509
1510 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1511                             u32 mark)
1512 {
1513         const struct ipv6hdr *iph = ipv6_hdr(skb);
1514         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1515         struct dst_entry *dst;
1516         struct flowi6 fl6;
1517
1518         memset(&fl6, 0, sizeof(fl6));
1519         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1520         fl6.flowi6_oif = oif;
1521         fl6.flowi6_mark = mark;
1522         fl6.daddr = msg->dest;
1523         fl6.saddr = iph->daddr;
1524
1525         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1526         rt6_do_redirect(dst, NULL, skb);
1527         dst_release(dst);
1528 }
1529
1530 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1531 {
1532         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1533 }
1534 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1535
1536 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1537 {
1538         struct net_device *dev = dst->dev;
1539         unsigned int mtu = dst_mtu(dst);
1540         struct net *net = dev_net(dev);
1541
1542         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1543
1544         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1545                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1546
1547         /*
1548          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1549          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1550          * IPV6_MAXPLEN is also valid and means: "any MSS,
1551          * rely only on pmtu discovery"
1552          */
1553         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1554                 mtu = IPV6_MAXPLEN;
1555         return mtu;
1556 }
1557
1558 static unsigned int ip6_mtu(const struct dst_entry *dst)
1559 {
1560         const struct rt6_info *rt = (const struct rt6_info *)dst;
1561         unsigned int mtu = rt->rt6i_pmtu;
1562         struct inet6_dev *idev;
1563
1564         if (mtu)
1565                 goto out;
1566
1567         mtu = dst_metric_raw(dst, RTAX_MTU);
1568         if (mtu)
1569                 goto out;
1570
1571         mtu = IPV6_MIN_MTU;
1572
1573         rcu_read_lock();
1574         idev = __in6_dev_get(dst->dev);
1575         if (idev)
1576                 mtu = idev->cnf.mtu6;
1577         rcu_read_unlock();
1578
1579 out:
1580         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1581 }
1582
1583 static struct dst_entry *icmp6_dst_gc_list;
1584 static DEFINE_SPINLOCK(icmp6_dst_lock);
1585
1586 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1587                                   struct flowi6 *fl6)
1588 {
1589         struct dst_entry *dst;
1590         struct rt6_info *rt;
1591         struct inet6_dev *idev = in6_dev_get(dev);
1592         struct net *net = dev_net(dev);
1593
1594         if (unlikely(!idev))
1595                 return ERR_PTR(-ENODEV);
1596
1597         rt = ip6_dst_alloc(net, dev, 0);
1598         if (unlikely(!rt)) {
1599                 in6_dev_put(idev);
1600                 dst = ERR_PTR(-ENOMEM);
1601                 goto out;
1602         }
1603
1604         rt->dst.flags |= DST_HOST;
1605         rt->dst.output  = ip6_output;
1606         atomic_set(&rt->dst.__refcnt, 1);
1607         rt->rt6i_gateway  = fl6->daddr;
1608         rt->rt6i_dst.addr = fl6->daddr;
1609         rt->rt6i_dst.plen = 128;
1610         rt->rt6i_idev     = idev;
1611         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1612
1613         spin_lock_bh(&icmp6_dst_lock);
1614         rt->dst.next = icmp6_dst_gc_list;
1615         icmp6_dst_gc_list = &rt->dst;
1616         spin_unlock_bh(&icmp6_dst_lock);
1617
1618         fib6_force_start_gc(net);
1619
1620         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1621
1622 out:
1623         return dst;
1624 }
1625
1626 int icmp6_dst_gc(void)
1627 {
1628         struct dst_entry *dst, **pprev;
1629         int more = 0;
1630
1631         spin_lock_bh(&icmp6_dst_lock);
1632         pprev = &icmp6_dst_gc_list;
1633
1634         while ((dst = *pprev) != NULL) {
1635                 if (!atomic_read(&dst->__refcnt)) {
1636                         *pprev = dst->next;
1637                         dst_free(dst);
1638                 } else {
1639                         pprev = &dst->next;
1640                         ++more;
1641                 }
1642         }
1643
1644         spin_unlock_bh(&icmp6_dst_lock);
1645
1646         return more;
1647 }
1648
1649 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1650                             void *arg)
1651 {
1652         struct dst_entry *dst, **pprev;
1653
1654         spin_lock_bh(&icmp6_dst_lock);
1655         pprev = &icmp6_dst_gc_list;
1656         while ((dst = *pprev) != NULL) {
1657                 struct rt6_info *rt = (struct rt6_info *) dst;
1658                 if (func(rt, arg)) {
1659                         *pprev = dst->next;
1660                         dst_free(dst);
1661                 } else {
1662                         pprev = &dst->next;
1663                 }
1664         }
1665         spin_unlock_bh(&icmp6_dst_lock);
1666 }
1667
1668 static int ip6_dst_gc(struct dst_ops *ops)
1669 {
1670         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1671         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1672         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1673         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1674         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1675         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1676         int entries;
1677
1678         entries = dst_entries_get_fast(ops);
1679         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1680             entries <= rt_max_size)
1681                 goto out;
1682
1683         net->ipv6.ip6_rt_gc_expire++;
1684         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1685         entries = dst_entries_get_slow(ops);
1686         if (entries < ops->gc_thresh)
1687                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1688 out:
1689         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1690         return entries > rt_max_size;
1691 }
1692
1693 static int ip6_convert_metrics(struct mx6_config *mxc,
1694                                const struct fib6_config *cfg)
1695 {
1696         bool ecn_ca = false;
1697         struct nlattr *nla;
1698         int remaining;
1699         u32 *mp;
1700
1701         if (!cfg->fc_mx)
1702                 return 0;
1703
1704         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1705         if (unlikely(!mp))
1706                 return -ENOMEM;
1707
1708         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1709                 int type = nla_type(nla);
1710                 u32 val;
1711
1712                 if (!type)
1713                         continue;
1714                 if (unlikely(type > RTAX_MAX))
1715                         goto err;
1716
1717                 if (type == RTAX_CC_ALGO) {
1718                         char tmp[TCP_CA_NAME_MAX];
1719
1720                         nla_strlcpy(tmp, nla, sizeof(tmp));
1721                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1722                         if (val == TCP_CA_UNSPEC)
1723                                 goto err;
1724                 } else {
1725                         val = nla_get_u32(nla);
1726                 }
1727                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1728                         goto err;
1729
1730                 mp[type - 1] = val;
1731                 __set_bit(type - 1, mxc->mx_valid);
1732         }
1733
1734         if (ecn_ca) {
1735                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1736                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1737         }
1738
1739         mxc->mx = mp;
1740         return 0;
1741  err:
1742         kfree(mp);
1743         return -EINVAL;
1744 }
1745
1746 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1747 {
1748         struct net *net = cfg->fc_nlinfo.nl_net;
1749         struct rt6_info *rt = NULL;
1750         struct net_device *dev = NULL;
1751         struct inet6_dev *idev = NULL;
1752         struct fib6_table *table;
1753         int addr_type;
1754         int err = -EINVAL;
1755
1756         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1757                 goto out;
1758 #ifndef CONFIG_IPV6_SUBTREES
1759         if (cfg->fc_src_len)
1760                 goto out;
1761 #endif
1762         if (cfg->fc_ifindex) {
1763                 err = -ENODEV;
1764                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1765                 if (!dev)
1766                         goto out;
1767                 idev = in6_dev_get(dev);
1768                 if (!idev)
1769                         goto out;
1770         }
1771
1772         if (cfg->fc_metric == 0)
1773                 cfg->fc_metric = IP6_RT_PRIO_USER;
1774
1775         err = -ENOBUFS;
1776         if (cfg->fc_nlinfo.nlh &&
1777             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1778                 table = fib6_get_table(net, cfg->fc_table);
1779                 if (!table) {
1780                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1781                         table = fib6_new_table(net, cfg->fc_table);
1782                 }
1783         } else {
1784                 table = fib6_new_table(net, cfg->fc_table);
1785         }
1786
1787         if (!table)
1788                 goto out;
1789
1790         rt = ip6_dst_alloc(net, NULL,
1791                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1792
1793         if (!rt) {
1794                 err = -ENOMEM;
1795                 goto out;
1796         }
1797
1798         if (cfg->fc_flags & RTF_EXPIRES)
1799                 rt6_set_expires(rt, jiffies +
1800                                 clock_t_to_jiffies(cfg->fc_expires));
1801         else
1802                 rt6_clean_expires(rt);
1803
1804         if (cfg->fc_protocol == RTPROT_UNSPEC)
1805                 cfg->fc_protocol = RTPROT_BOOT;
1806         rt->rt6i_protocol = cfg->fc_protocol;
1807
1808         addr_type = ipv6_addr_type(&cfg->fc_dst);
1809
1810         if (addr_type & IPV6_ADDR_MULTICAST)
1811                 rt->dst.input = ip6_mc_input;
1812         else if (cfg->fc_flags & RTF_LOCAL)
1813                 rt->dst.input = ip6_input;
1814         else
1815                 rt->dst.input = ip6_forward;
1816
1817         rt->dst.output = ip6_output;
1818
1819         if (cfg->fc_encap) {
1820                 struct lwtunnel_state *lwtstate;
1821
1822                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1823                                            cfg->fc_encap, AF_INET6, cfg,
1824                                            &lwtstate);
1825                 if (err)
1826                         goto out;
1827                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1828                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1829                         rt->dst.lwtstate->orig_output = rt->dst.output;
1830                         rt->dst.output = lwtunnel_output;
1831                 }
1832                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1833                         rt->dst.lwtstate->orig_input = rt->dst.input;
1834                         rt->dst.input = lwtunnel_input;
1835                 }
1836         }
1837
1838         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1839         rt->rt6i_dst.plen = cfg->fc_dst_len;
1840         if (rt->rt6i_dst.plen == 128)
1841                 rt->dst.flags |= DST_HOST;
1842
1843 #ifdef CONFIG_IPV6_SUBTREES
1844         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1845         rt->rt6i_src.plen = cfg->fc_src_len;
1846 #endif
1847
1848         rt->rt6i_metric = cfg->fc_metric;
1849
1850         /* We cannot add true routes via loopback here,
1851            they would result in kernel looping; promote them to reject routes
1852          */
1853         if ((cfg->fc_flags & RTF_REJECT) ||
1854             (dev && (dev->flags & IFF_LOOPBACK) &&
1855              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1856              !(cfg->fc_flags & RTF_LOCAL))) {
1857                 /* hold loopback dev/idev if we haven't done so. */
1858                 if (dev != net->loopback_dev) {
1859                         if (dev) {
1860                                 dev_put(dev);
1861                                 in6_dev_put(idev);
1862                         }
1863                         dev = net->loopback_dev;
1864                         dev_hold(dev);
1865                         idev = in6_dev_get(dev);
1866                         if (!idev) {
1867                                 err = -ENODEV;
1868                                 goto out;
1869                         }
1870                 }
1871                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1872                 switch (cfg->fc_type) {
1873                 case RTN_BLACKHOLE:
1874                         rt->dst.error = -EINVAL;
1875                         rt->dst.output = dst_discard_out;
1876                         rt->dst.input = dst_discard;
1877                         break;
1878                 case RTN_PROHIBIT:
1879                         rt->dst.error = -EACCES;
1880                         rt->dst.output = ip6_pkt_prohibit_out;
1881                         rt->dst.input = ip6_pkt_prohibit;
1882                         break;
1883                 case RTN_THROW:
1884                 case RTN_UNREACHABLE:
1885                 default:
1886                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1887                                         : (cfg->fc_type == RTN_UNREACHABLE)
1888                                         ? -EHOSTUNREACH : -ENETUNREACH;
1889                         rt->dst.output = ip6_pkt_discard_out;
1890                         rt->dst.input = ip6_pkt_discard;
1891                         break;
1892                 }
1893                 goto install_route;
1894         }
1895
1896         if (cfg->fc_flags & RTF_GATEWAY) {
1897                 const struct in6_addr *gw_addr;
1898                 int gwa_type;
1899
1900                 gw_addr = &cfg->fc_gateway;
1901                 gwa_type = ipv6_addr_type(gw_addr);
1902
1903                 /* if gw_addr is local we will fail to detect this in case
1904                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1905                  * will return already-added prefix route via interface that
1906                  * prefix route was assigned to, which might be non-loopback.
1907                  */
1908                 err = -EINVAL;
1909                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1910                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1911                                             dev : NULL, 0, 0))
1912                         goto out;
1913
1914                 rt->rt6i_gateway = *gw_addr;
1915
1916                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1917                         struct rt6_info *grt;
1918
1919                         /* IPv6 strictly inhibits using not link-local
1920                            addresses as nexthop address.
1921                            Otherwise, router will not able to send redirects.
1922                            It is very good, but in some (rare!) circumstances
1923                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1924                            some exceptions. --ANK
1925                          */
1926                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1927                                 goto out;
1928
1929                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1930
1931                         err = -EHOSTUNREACH;
1932                         if (!grt)
1933                                 goto out;
1934                         if (dev) {
1935                                 if (dev != grt->dst.dev) {
1936                                         ip6_rt_put(grt);
1937                                         goto out;
1938                                 }
1939                         } else {
1940                                 dev = grt->dst.dev;
1941                                 idev = grt->rt6i_idev;
1942                                 dev_hold(dev);
1943                                 in6_dev_hold(grt->rt6i_idev);
1944                         }
1945                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1946                                 err = 0;
1947                         ip6_rt_put(grt);
1948
1949                         if (err)
1950                                 goto out;
1951                 }
1952                 err = -EINVAL;
1953                 if (!dev || (dev->flags & IFF_LOOPBACK))
1954                         goto out;
1955         }
1956
1957         err = -ENODEV;
1958         if (!dev)
1959                 goto out;
1960
1961         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1962                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1963                         err = -EINVAL;
1964                         goto out;
1965                 }
1966                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1967                 rt->rt6i_prefsrc.plen = 128;
1968         } else
1969                 rt->rt6i_prefsrc.plen = 0;
1970
1971         rt->rt6i_flags = cfg->fc_flags;
1972
1973 install_route:
1974         rt->dst.dev = dev;
1975         rt->rt6i_idev = idev;
1976         rt->rt6i_table = table;
1977
1978         cfg->fc_nlinfo.nl_net = dev_net(dev);
1979
1980         return rt;
1981 out:
1982         if (dev)
1983                 dev_put(dev);
1984         if (idev)
1985                 in6_dev_put(idev);
1986         if (rt)
1987                 dst_free(&rt->dst);
1988
1989         return ERR_PTR(err);
1990 }
1991
1992 int ip6_route_add(struct fib6_config *cfg)
1993 {
1994         struct mx6_config mxc = { .mx = NULL, };
1995         struct rt6_info *rt;
1996         int err;
1997
1998         rt = ip6_route_info_create(cfg);
1999         if (IS_ERR(rt)) {
2000                 err = PTR_ERR(rt);
2001                 rt = NULL;
2002                 goto out;
2003         }
2004
2005         err = ip6_convert_metrics(&mxc, cfg);
2006         if (err)
2007                 goto out;
2008
2009         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2010
2011         kfree(mxc.mx);
2012
2013         return err;
2014 out:
2015         if (rt)
2016                 dst_free(&rt->dst);
2017
2018         return err;
2019 }
2020
2021 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2022 {
2023         int err;
2024         struct fib6_table *table;
2025         struct net *net = dev_net(rt->dst.dev);
2026
2027         if (rt == net->ipv6.ip6_null_entry ||
2028             rt->dst.flags & DST_NOCACHE) {
2029                 err = -ENOENT;
2030                 goto out;
2031         }
2032
2033         table = rt->rt6i_table;
2034         write_lock_bh(&table->tb6_lock);
2035         err = fib6_del(rt, info);
2036         write_unlock_bh(&table->tb6_lock);
2037
2038 out:
2039         ip6_rt_put(rt);
2040         return err;
2041 }
2042
2043 int ip6_del_rt(struct rt6_info *rt)
2044 {
2045         struct nl_info info = {
2046                 .nl_net = dev_net(rt->dst.dev),
2047         };
2048         return __ip6_del_rt(rt, &info);
2049 }
2050
2051 static int ip6_route_del(struct fib6_config *cfg)
2052 {
2053         struct fib6_table *table;
2054         struct fib6_node *fn;
2055         struct rt6_info *rt;
2056         int err = -ESRCH;
2057
2058         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2059         if (!table)
2060                 return err;
2061
2062         read_lock_bh(&table->tb6_lock);
2063
2064         fn = fib6_locate(&table->tb6_root,
2065                          &cfg->fc_dst, cfg->fc_dst_len,
2066                          &cfg->fc_src, cfg->fc_src_len);
2067
2068         if (fn) {
2069                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2070                         if ((rt->rt6i_flags & RTF_CACHE) &&
2071                             !(cfg->fc_flags & RTF_CACHE))
2072                                 continue;
2073                         if (cfg->fc_ifindex &&
2074                             (!rt->dst.dev ||
2075                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2076                                 continue;
2077                         if (cfg->fc_flags & RTF_GATEWAY &&
2078                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2079                                 continue;
2080                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2081                                 continue;
2082                         dst_hold(&rt->dst);
2083                         read_unlock_bh(&table->tb6_lock);
2084
2085                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2086                 }
2087         }
2088         read_unlock_bh(&table->tb6_lock);
2089
2090         return err;
2091 }
2092
2093 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2094 {
2095         struct netevent_redirect netevent;
2096         struct rt6_info *rt, *nrt = NULL;
2097         struct ndisc_options ndopts;
2098         struct inet6_dev *in6_dev;
2099         struct neighbour *neigh;
2100         struct rd_msg *msg;
2101         int optlen, on_link;
2102         u8 *lladdr;
2103
2104         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2105         optlen -= sizeof(*msg);
2106
2107         if (optlen < 0) {
2108                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2109                 return;
2110         }
2111
2112         msg = (struct rd_msg *)icmp6_hdr(skb);
2113
2114         if (ipv6_addr_is_multicast(&msg->dest)) {
2115                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2116                 return;
2117         }
2118
2119         on_link = 0;
2120         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2121                 on_link = 1;
2122         } else if (ipv6_addr_type(&msg->target) !=
2123                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2124                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2125                 return;
2126         }
2127
2128         in6_dev = __in6_dev_get(skb->dev);
2129         if (!in6_dev)
2130                 return;
2131         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2132                 return;
2133
2134         /* RFC2461 8.1:
2135          *      The IP source address of the Redirect MUST be the same as the current
2136          *      first-hop router for the specified ICMP Destination Address.
2137          */
2138
2139         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2140                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2141                 return;
2142         }
2143
2144         lladdr = NULL;
2145         if (ndopts.nd_opts_tgt_lladdr) {
2146                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2147                                              skb->dev);
2148                 if (!lladdr) {
2149                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2150                         return;
2151                 }
2152         }
2153
2154         rt = (struct rt6_info *) dst;
2155         if (rt->rt6i_flags & RTF_REJECT) {
2156                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2157                 return;
2158         }
2159
2160         /* Redirect received -> path was valid.
2161          * Look, redirects are sent only in response to data packets,
2162          * so that this nexthop apparently is reachable. --ANK
2163          */
2164         dst_confirm(&rt->dst);
2165
2166         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2167         if (!neigh)
2168                 return;
2169
2170         /*
2171          *      We have finally decided to accept it.
2172          */
2173
2174         neigh_update(neigh, lladdr, NUD_STALE,
2175                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2176                      NEIGH_UPDATE_F_OVERRIDE|
2177                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2178                                      NEIGH_UPDATE_F_ISROUTER))
2179                      );
2180
2181         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2182         if (!nrt)
2183                 goto out;
2184
2185         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2186         if (on_link)
2187                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2188
2189         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2190
2191         if (ip6_ins_rt(nrt))
2192                 goto out;
2193
2194         netevent.old = &rt->dst;
2195         netevent.new = &nrt->dst;
2196         netevent.daddr = &msg->dest;
2197         netevent.neigh = neigh;
2198         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2199
2200         if (rt->rt6i_flags & RTF_CACHE) {
2201                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2202                 ip6_del_rt(rt);
2203         }
2204
2205 out:
2206         neigh_release(neigh);
2207 }
2208
2209 /*
2210  *      Misc support functions
2211  */
2212
2213 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2214 {
2215         BUG_ON(from->dst.from);
2216
2217         rt->rt6i_flags &= ~RTF_EXPIRES;
2218         dst_hold(&from->dst);
2219         rt->dst.from = &from->dst;
2220         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2221 }
2222
2223 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2224 {
2225         rt->dst.input = ort->dst.input;
2226         rt->dst.output = ort->dst.output;
2227         rt->rt6i_dst = ort->rt6i_dst;
2228         rt->dst.error = ort->dst.error;
2229         rt->rt6i_idev = ort->rt6i_idev;
2230         if (rt->rt6i_idev)
2231                 in6_dev_hold(rt->rt6i_idev);
2232         rt->dst.lastuse = jiffies;
2233         rt->rt6i_gateway = ort->rt6i_gateway;
2234         rt->rt6i_flags = ort->rt6i_flags;
2235         rt6_set_from(rt, ort);
2236         rt->rt6i_metric = ort->rt6i_metric;
2237 #ifdef CONFIG_IPV6_SUBTREES
2238         rt->rt6i_src = ort->rt6i_src;
2239 #endif
2240         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2241         rt->rt6i_table = ort->rt6i_table;
2242         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2243 }
2244
2245 #ifdef CONFIG_IPV6_ROUTE_INFO
2246 static struct rt6_info *rt6_get_route_info(struct net_device *dev,
2247                                            const struct in6_addr *prefix, int prefixlen,
2248                                            const struct in6_addr *gwaddr)
2249 {
2250         struct fib6_node *fn;
2251         struct rt6_info *rt = NULL;
2252         struct fib6_table *table;
2253
2254         table = fib6_get_table(dev_net(dev),
2255                                addrconf_rt_table(dev, RT6_TABLE_INFO));
2256         if (!table)
2257                 return NULL;
2258
2259         read_lock_bh(&table->tb6_lock);
2260         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2261         if (!fn)
2262                 goto out;
2263
2264         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2265                 if (rt->dst.dev->ifindex != dev->ifindex)
2266                         continue;
2267                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2268                         continue;
2269                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2270                         continue;
2271                 dst_hold(&rt->dst);
2272                 break;
2273         }
2274 out:
2275         read_unlock_bh(&table->tb6_lock);
2276         return rt;
2277 }
2278
2279 static struct rt6_info *rt6_add_route_info(struct net_device *dev,
2280                                            const struct in6_addr *prefix, int prefixlen,
2281                                            const struct in6_addr *gwaddr, unsigned int pref)
2282 {
2283         struct fib6_config cfg = {
2284                 .fc_metric      = IP6_RT_PRIO_USER,
2285                 .fc_ifindex     = dev->ifindex,
2286                 .fc_dst_len     = prefixlen,
2287                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2288                                   RTF_UP | RTF_PREF(pref),
2289                 .fc_nlinfo.portid = 0,
2290                 .fc_nlinfo.nlh = NULL,
2291                 .fc_nlinfo.nl_net = dev_net(dev),
2292         };
2293
2294         cfg.fc_table = l3mdev_fib_table_by_index(dev_net(dev), dev->ifindex) ? : addrconf_rt_table(dev, RT6_TABLE_INFO);
2295         cfg.fc_dst = *prefix;
2296         cfg.fc_gateway = *gwaddr;
2297
2298         /* We should treat it as a default route if prefix length is 0. */
2299         if (!prefixlen)
2300                 cfg.fc_flags |= RTF_DEFAULT;
2301
2302         ip6_route_add(&cfg);
2303
2304         return rt6_get_route_info(dev, prefix, prefixlen, gwaddr);
2305 }
2306 #endif
2307
2308 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2309 {
2310         struct rt6_info *rt;
2311         struct fib6_table *table;
2312
2313         table = fib6_get_table(dev_net(dev),
2314                                addrconf_rt_table(dev, RT6_TABLE_MAIN));
2315         if (!table)
2316                 return NULL;
2317
2318         read_lock_bh(&table->tb6_lock);
2319         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2320                 if (dev == rt->dst.dev &&
2321                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2322                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2323                         break;
2324         }
2325         if (rt)
2326                 dst_hold(&rt->dst);
2327         read_unlock_bh(&table->tb6_lock);
2328         return rt;
2329 }
2330
2331 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2332                                      struct net_device *dev,
2333                                      unsigned int pref)
2334 {
2335         struct fib6_config cfg = {
2336                 .fc_table       = l3mdev_fib_table(dev) ? : addrconf_rt_table(dev, RT6_TABLE_DFLT),
2337                 .fc_metric      = IP6_RT_PRIO_USER,
2338                 .fc_ifindex     = dev->ifindex,
2339                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2340                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2341                 .fc_nlinfo.portid = 0,
2342                 .fc_nlinfo.nlh = NULL,
2343                 .fc_nlinfo.nl_net = dev_net(dev),
2344         };
2345
2346         cfg.fc_gateway = *gwaddr;
2347
2348         ip6_route_add(&cfg);
2349
2350         return rt6_get_dflt_router(gwaddr, dev);
2351 }
2352
2353
2354 int rt6_addrconf_purge(struct rt6_info *rt, void *arg) {
2355         if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2356             (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2))
2357                 return -1;
2358         return 0;
2359 }
2360
2361 void rt6_purge_dflt_routers(struct net *net)
2362 {
2363         fib6_clean_all(net, rt6_addrconf_purge, NULL);
2364 }
2365
2366 static void rtmsg_to_fib6_config(struct net *net,
2367                                  struct in6_rtmsg *rtmsg,
2368                                  struct fib6_config *cfg)
2369 {
2370         memset(cfg, 0, sizeof(*cfg));
2371
2372         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2373                          : RT6_TABLE_MAIN;
2374         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2375         cfg->fc_metric = rtmsg->rtmsg_metric;
2376         cfg->fc_expires = rtmsg->rtmsg_info;
2377         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2378         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2379         cfg->fc_flags = rtmsg->rtmsg_flags;
2380
2381         cfg->fc_nlinfo.nl_net = net;
2382
2383         cfg->fc_dst = rtmsg->rtmsg_dst;
2384         cfg->fc_src = rtmsg->rtmsg_src;
2385         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2386 }
2387
2388 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2389 {
2390         struct fib6_config cfg;
2391         struct in6_rtmsg rtmsg;
2392         int err;
2393
2394         switch (cmd) {
2395         case SIOCADDRT:         /* Add a route */
2396         case SIOCDELRT:         /* Delete a route */
2397                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2398                         return -EPERM;
2399                 err = copy_from_user(&rtmsg, arg,
2400                                      sizeof(struct in6_rtmsg));
2401                 if (err)
2402                         return -EFAULT;
2403
2404                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2405
2406                 rtnl_lock();
2407                 switch (cmd) {
2408                 case SIOCADDRT:
2409                         err = ip6_route_add(&cfg);
2410                         break;
2411                 case SIOCDELRT:
2412                         err = ip6_route_del(&cfg);
2413                         break;
2414                 default:
2415                         err = -EINVAL;
2416                 }
2417                 rtnl_unlock();
2418
2419                 return err;
2420         }
2421
2422         return -EINVAL;
2423 }
2424
2425 /*
2426  *      Drop the packet on the floor
2427  */
2428
2429 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2430 {
2431         int type;
2432         struct dst_entry *dst = skb_dst(skb);
2433         switch (ipstats_mib_noroutes) {
2434         case IPSTATS_MIB_INNOROUTES:
2435                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2436                 if (type == IPV6_ADDR_ANY) {
2437                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2438                                       IPSTATS_MIB_INADDRERRORS);
2439                         break;
2440                 }
2441                 /* FALLTHROUGH */
2442         case IPSTATS_MIB_OUTNOROUTES:
2443                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2444                               ipstats_mib_noroutes);
2445                 break;
2446         }
2447         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2448         kfree_skb(skb);
2449         return 0;
2450 }
2451
2452 static int ip6_pkt_discard(struct sk_buff *skb)
2453 {
2454         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2455 }
2456
2457 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2458 {
2459         skb->dev = skb_dst(skb)->dev;
2460         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2461 }
2462
2463 static int ip6_pkt_prohibit(struct sk_buff *skb)
2464 {
2465         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2466 }
2467
2468 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2469 {
2470         skb->dev = skb_dst(skb)->dev;
2471         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2472 }
2473
2474 /*
2475  *      Allocate a dst for local (unicast / anycast) address.
2476  */
2477
2478 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2479                                     const struct in6_addr *addr,
2480                                     bool anycast)
2481 {
2482         u32 tb_id;
2483         struct net *net = dev_net(idev->dev);
2484         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2485                                             DST_NOCOUNT);
2486         if (!rt)
2487                 return ERR_PTR(-ENOMEM);
2488
2489         in6_dev_hold(idev);
2490
2491         rt->dst.flags |= DST_HOST;
2492         rt->dst.input = ip6_input;
2493         rt->dst.output = ip6_output;
2494         rt->rt6i_idev = idev;
2495
2496         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2497         if (anycast)
2498                 rt->rt6i_flags |= RTF_ANYCAST;
2499         else
2500                 rt->rt6i_flags |= RTF_LOCAL;
2501
2502         rt->rt6i_gateway  = *addr;
2503         rt->rt6i_dst.addr = *addr;
2504         rt->rt6i_dst.plen = 128;
2505         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2506         rt->rt6i_table = fib6_get_table(net, tb_id);
2507         rt->dst.flags |= DST_NOCACHE;
2508
2509         atomic_set(&rt->dst.__refcnt, 1);
2510
2511         return rt;
2512 }
2513
2514 int ip6_route_get_saddr(struct net *net,
2515                         struct rt6_info *rt,
2516                         const struct in6_addr *daddr,
2517                         unsigned int prefs,
2518                         struct in6_addr *saddr)
2519 {
2520         struct inet6_dev *idev =
2521                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2522         int err = 0;
2523         if (rt && rt->rt6i_prefsrc.plen)
2524                 *saddr = rt->rt6i_prefsrc.addr;
2525         else
2526                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2527                                          daddr, prefs, saddr);
2528         return err;
2529 }
2530
2531 /* remove deleted ip from prefsrc entries */
2532 struct arg_dev_net_ip {
2533         struct net_device *dev;
2534         struct net *net;
2535         struct in6_addr *addr;
2536 };
2537
2538 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2539 {
2540         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2541         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2542         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2543
2544         if (((void *)rt->dst.dev == dev || !dev) &&
2545             rt != net->ipv6.ip6_null_entry &&
2546             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2547                 /* remove prefsrc entry */
2548                 rt->rt6i_prefsrc.plen = 0;
2549         }
2550         return 0;
2551 }
2552
2553 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2554 {
2555         struct net *net = dev_net(ifp->idev->dev);
2556         struct arg_dev_net_ip adni = {
2557                 .dev = ifp->idev->dev,
2558                 .net = net,
2559                 .addr = &ifp->addr,
2560         };
2561         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2562 }
2563
2564 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2565 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2566
2567 /* Remove routers and update dst entries when gateway turn into host. */
2568 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2569 {
2570         struct in6_addr *gateway = (struct in6_addr *)arg;
2571
2572         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2573              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2574              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2575                 return -1;
2576         }
2577         return 0;
2578 }
2579
2580 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2581 {
2582         fib6_clean_all(net, fib6_clean_tohost, gateway);
2583 }
2584
2585 struct arg_dev_net {
2586         struct net_device *dev;
2587         struct net *net;
2588 };
2589
2590 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2591 {
2592         const struct arg_dev_net *adn = arg;
2593         const struct net_device *dev = adn->dev;
2594
2595         if ((rt->dst.dev == dev || !dev) &&
2596             rt != adn->net->ipv6.ip6_null_entry)
2597                 return -1;
2598
2599         return 0;
2600 }
2601
2602 void rt6_ifdown(struct net *net, struct net_device *dev)
2603 {
2604         struct arg_dev_net adn = {
2605                 .dev = dev,
2606                 .net = net,
2607         };
2608
2609         fib6_clean_all(net, fib6_ifdown, &adn);
2610         icmp6_clean_all(fib6_ifdown, &adn);
2611         if (dev)
2612                 rt6_uncached_list_flush_dev(net, dev);
2613 }
2614
2615 struct rt6_mtu_change_arg {
2616         struct net_device *dev;
2617         unsigned int mtu;
2618 };
2619
2620 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2621 {
2622         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2623         struct inet6_dev *idev;
2624
2625         /* In IPv6 pmtu discovery is not optional,
2626            so that RTAX_MTU lock cannot disable it.
2627            We still use this lock to block changes
2628            caused by addrconf/ndisc.
2629         */
2630
2631         idev = __in6_dev_get(arg->dev);
2632         if (!idev)
2633                 return 0;
2634
2635         /* For administrative MTU increase, there is no way to discover
2636            IPv6 PMTU increase, so PMTU increase should be updated here.
2637            Since RFC 1981 doesn't include administrative MTU increase
2638            update PMTU increase is a MUST. (i.e. jumbo frame)
2639          */
2640         /*
2641            If new MTU is less than route PMTU, this new MTU will be the
2642            lowest MTU in the path, update the route PMTU to reflect PMTU
2643            decreases; if new MTU is greater than route PMTU, and the
2644            old MTU is the lowest MTU in the path, update the route PMTU
2645            to reflect the increase. In this case if the other nodes' MTU
2646            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2647            PMTU discouvery.
2648          */
2649         if (rt->dst.dev == arg->dev &&
2650             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2651                 if (rt->rt6i_flags & RTF_CACHE) {
2652                         /* For RTF_CACHE with rt6i_pmtu == 0
2653                          * (i.e. a redirected route),
2654                          * the metrics of its rt->dst.from has already
2655                          * been updated.
2656                          */
2657                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2658                                 rt->rt6i_pmtu = arg->mtu;
2659                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2660                            (dst_mtu(&rt->dst) < arg->mtu &&
2661                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2662                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2663                 }
2664         }
2665         return 0;
2666 }
2667
2668 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2669 {
2670         struct rt6_mtu_change_arg arg = {
2671                 .dev = dev,
2672                 .mtu = mtu,
2673         };
2674
2675         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2676 }
2677
2678 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2679         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2680         [RTA_OIF]               = { .type = NLA_U32 },
2681         [RTA_IIF]               = { .type = NLA_U32 },
2682         [RTA_PRIORITY]          = { .type = NLA_U32 },
2683         [RTA_METRICS]           = { .type = NLA_NESTED },
2684         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2685         [RTA_PREF]              = { .type = NLA_U8 },
2686         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2687         [RTA_ENCAP]             = { .type = NLA_NESTED },
2688 };
2689
2690 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2691                               struct fib6_config *cfg)
2692 {
2693         struct rtmsg *rtm;
2694         struct nlattr *tb[RTA_MAX+1];
2695         unsigned int pref;
2696         int err;
2697
2698         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2699         if (err < 0)
2700                 goto errout;
2701
2702         err = -EINVAL;
2703         rtm = nlmsg_data(nlh);
2704         memset(cfg, 0, sizeof(*cfg));
2705
2706         cfg->fc_table = rtm->rtm_table;
2707         cfg->fc_dst_len = rtm->rtm_dst_len;
2708         cfg->fc_src_len = rtm->rtm_src_len;
2709         cfg->fc_flags = RTF_UP;
2710         cfg->fc_protocol = rtm->rtm_protocol;
2711         cfg->fc_type = rtm->rtm_type;
2712
2713         if (rtm->rtm_type == RTN_UNREACHABLE ||
2714             rtm->rtm_type == RTN_BLACKHOLE ||
2715             rtm->rtm_type == RTN_PROHIBIT ||
2716             rtm->rtm_type == RTN_THROW)
2717                 cfg->fc_flags |= RTF_REJECT;
2718
2719         if (rtm->rtm_type == RTN_LOCAL)
2720                 cfg->fc_flags |= RTF_LOCAL;
2721
2722         if (rtm->rtm_flags & RTM_F_CLONED)
2723                 cfg->fc_flags |= RTF_CACHE;
2724
2725         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2726         cfg->fc_nlinfo.nlh = nlh;
2727         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2728
2729         if (tb[RTA_GATEWAY]) {
2730                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2731                 cfg->fc_flags |= RTF_GATEWAY;
2732         }
2733
2734         if (tb[RTA_DST]) {
2735                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2736
2737                 if (nla_len(tb[RTA_DST]) < plen)
2738                         goto errout;
2739
2740                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2741         }
2742
2743         if (tb[RTA_SRC]) {
2744                 int plen = (rtm->rtm_src_len + 7) >> 3;
2745
2746                 if (nla_len(tb[RTA_SRC]) < plen)
2747                         goto errout;
2748
2749                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2750         }
2751
2752         if (tb[RTA_PREFSRC])
2753                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2754
2755         if (tb[RTA_OIF])
2756                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2757
2758         if (tb[RTA_PRIORITY])
2759                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2760
2761         if (tb[RTA_METRICS]) {
2762                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2763                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2764         }
2765
2766         if (tb[RTA_TABLE])
2767                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2768
2769         if (tb[RTA_MULTIPATH]) {
2770                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2771                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2772         }
2773
2774         if (tb[RTA_PREF]) {
2775                 pref = nla_get_u8(tb[RTA_PREF]);
2776                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2777                     pref != ICMPV6_ROUTER_PREF_HIGH)
2778                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2779                 cfg->fc_flags |= RTF_PREF(pref);
2780         }
2781
2782         if (tb[RTA_ENCAP])
2783                 cfg->fc_encap = tb[RTA_ENCAP];
2784
2785         if (tb[RTA_ENCAP_TYPE])
2786                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2787
2788         err = 0;
2789 errout:
2790         return err;
2791 }
2792
2793 struct rt6_nh {
2794         struct rt6_info *rt6_info;
2795         struct fib6_config r_cfg;
2796         struct mx6_config mxc;
2797         struct list_head next;
2798 };
2799
2800 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2801 {
2802         struct rt6_nh *nh;
2803
2804         list_for_each_entry(nh, rt6_nh_list, next) {
2805                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2806                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2807                         nh->r_cfg.fc_ifindex);
2808         }
2809 }
2810
2811 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2812                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2813 {
2814         struct rt6_nh *nh;
2815         struct rt6_info *rtnh;
2816         int err = -EEXIST;
2817
2818         list_for_each_entry(nh, rt6_nh_list, next) {
2819                 /* check if rt6_info already exists */
2820                 rtnh = nh->rt6_info;
2821
2822                 if (rtnh->dst.dev == rt->dst.dev &&
2823                     rtnh->rt6i_idev == rt->rt6i_idev &&
2824                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2825                                     &rt->rt6i_gateway))
2826                         return err;
2827         }
2828
2829         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2830         if (!nh)
2831                 return -ENOMEM;
2832         nh->rt6_info = rt;
2833         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2834         if (err) {
2835                 kfree(nh);
2836                 return err;
2837         }
2838         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2839         list_add_tail(&nh->next, rt6_nh_list);
2840
2841         return 0;
2842 }
2843
2844 static int ip6_route_multipath_add(struct fib6_config *cfg)
2845 {
2846         struct fib6_config r_cfg;
2847         struct rtnexthop *rtnh;
2848         struct rt6_info *rt;
2849         struct rt6_nh *err_nh;
2850         struct rt6_nh *nh, *nh_safe;
2851         int remaining;
2852         int attrlen;
2853         int err = 1;
2854         int nhn = 0;
2855         int replace = (cfg->fc_nlinfo.nlh &&
2856                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2857         LIST_HEAD(rt6_nh_list);
2858
2859         remaining = cfg->fc_mp_len;
2860         rtnh = (struct rtnexthop *)cfg->fc_mp;
2861
2862         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2863          * rt6_info structs per nexthop
2864          */
2865         while (rtnh_ok(rtnh, remaining)) {
2866                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2867                 if (rtnh->rtnh_ifindex)
2868                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2869
2870                 attrlen = rtnh_attrlen(rtnh);
2871                 if (attrlen > 0) {
2872                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2873
2874                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2875                         if (nla) {
2876                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2877                                 r_cfg.fc_flags |= RTF_GATEWAY;
2878                         }
2879                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2880                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2881                         if (nla)
2882                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2883                 }
2884
2885                 rt = ip6_route_info_create(&r_cfg);
2886                 if (IS_ERR(rt)) {
2887                         err = PTR_ERR(rt);
2888                         rt = NULL;
2889                         goto cleanup;
2890                 }
2891
2892                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2893                 if (err) {
2894                         dst_free(&rt->dst);
2895                         goto cleanup;
2896                 }
2897
2898                 rtnh = rtnh_next(rtnh, &remaining);
2899         }
2900
2901         err_nh = NULL;
2902         list_for_each_entry(nh, &rt6_nh_list, next) {
2903                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2904                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2905                 nh->rt6_info = NULL;
2906                 if (err) {
2907                         if (replace && nhn)
2908                                 ip6_print_replace_route_err(&rt6_nh_list);
2909                         err_nh = nh;
2910                         goto add_errout;
2911                 }
2912
2913                 /* Because each route is added like a single route we remove
2914                  * these flags after the first nexthop: if there is a collision,
2915                  * we have already failed to add the first nexthop:
2916                  * fib6_add_rt2node() has rejected it; when replacing, old
2917                  * nexthops have been replaced by first new, the rest should
2918                  * be added to it.
2919                  */
2920                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2921                                                      NLM_F_REPLACE);
2922                 nhn++;
2923         }
2924
2925         goto cleanup;
2926
2927 add_errout:
2928         /* Delete routes that were already added */
2929         list_for_each_entry(nh, &rt6_nh_list, next) {
2930                 if (err_nh == nh)
2931                         break;
2932                 ip6_route_del(&nh->r_cfg);
2933         }
2934
2935 cleanup:
2936         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2937                 if (nh->rt6_info)
2938                         dst_free(&nh->rt6_info->dst);
2939                 kfree(nh->mxc.mx);
2940                 list_del(&nh->next);
2941                 kfree(nh);
2942         }
2943
2944         return err;
2945 }
2946
2947 static int ip6_route_multipath_del(struct fib6_config *cfg)
2948 {
2949         struct fib6_config r_cfg;
2950         struct rtnexthop *rtnh;
2951         int remaining;
2952         int attrlen;
2953         int err = 1, last_err = 0;
2954
2955         remaining = cfg->fc_mp_len;
2956         rtnh = (struct rtnexthop *)cfg->fc_mp;
2957
2958         /* Parse a Multipath Entry */
2959         while (rtnh_ok(rtnh, remaining)) {
2960                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2961                 if (rtnh->rtnh_ifindex)
2962                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2963
2964                 attrlen = rtnh_attrlen(rtnh);
2965                 if (attrlen > 0) {
2966                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2967
2968                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2969                         if (nla) {
2970                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2971                                 r_cfg.fc_flags |= RTF_GATEWAY;
2972                         }
2973                 }
2974                 err = ip6_route_del(&r_cfg);
2975                 if (err)
2976                         last_err = err;
2977
2978                 rtnh = rtnh_next(rtnh, &remaining);
2979         }
2980
2981         return last_err;
2982 }
2983
2984 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2985 {
2986         struct fib6_config cfg;
2987         int err;
2988
2989         err = rtm_to_fib6_config(skb, nlh, &cfg);
2990         if (err < 0)
2991                 return err;
2992
2993         if (cfg.fc_mp)
2994                 return ip6_route_multipath_del(&cfg);
2995         else
2996                 return ip6_route_del(&cfg);
2997 }
2998
2999 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3000 {
3001         struct fib6_config cfg;
3002         int err;
3003
3004         err = rtm_to_fib6_config(skb, nlh, &cfg);
3005         if (err < 0)
3006                 return err;
3007
3008         if (cfg.fc_mp)
3009                 return ip6_route_multipath_add(&cfg);
3010         else
3011                 return ip6_route_add(&cfg);
3012 }
3013
3014 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3015 {
3016         return NLMSG_ALIGN(sizeof(struct rtmsg))
3017                + nla_total_size(16) /* RTA_SRC */
3018                + nla_total_size(16) /* RTA_DST */
3019                + nla_total_size(16) /* RTA_GATEWAY */
3020                + nla_total_size(16) /* RTA_PREFSRC */
3021                + nla_total_size(4) /* RTA_TABLE */
3022                + nla_total_size(4) /* RTA_IIF */
3023                + nla_total_size(4) /* RTA_OIF */
3024                + nla_total_size(4) /* RTA_PRIORITY */
3025                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3026                + nla_total_size(sizeof(struct rta_cacheinfo))
3027                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3028                + nla_total_size(1) /* RTA_PREF */
3029                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3030 }
3031
3032 static int rt6_fill_node(struct net *net,
3033                          struct sk_buff *skb, struct rt6_info *rt,
3034                          struct in6_addr *dst, struct in6_addr *src,
3035                          int iif, int type, u32 portid, u32 seq,
3036                          int prefix, int nowait, unsigned int flags)
3037 {
3038         u32 metrics[RTAX_MAX];
3039         struct rtmsg *rtm;
3040         struct nlmsghdr *nlh;
3041         long expires;
3042         u32 table;
3043
3044         if (prefix) {   /* user wants prefix routes only */
3045                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3046                         /* success since this is not a prefix route */
3047                         return 1;
3048                 }
3049         }
3050
3051         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3052         if (!nlh)
3053                 return -EMSGSIZE;
3054
3055         rtm = nlmsg_data(nlh);
3056         rtm->rtm_family = AF_INET6;
3057         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3058         rtm->rtm_src_len = rt->rt6i_src.plen;
3059         rtm->rtm_tos = 0;
3060         if (rt->rt6i_table)
3061                 table = rt->rt6i_table->tb6_id;
3062         else
3063                 table = RT6_TABLE_UNSPEC;
3064         rtm->rtm_table = table;
3065         if (nla_put_u32(skb, RTA_TABLE, table))
3066                 goto nla_put_failure;
3067         if (rt->rt6i_flags & RTF_REJECT) {
3068                 switch (rt->dst.error) {
3069                 case -EINVAL:
3070                         rtm->rtm_type = RTN_BLACKHOLE;
3071                         break;
3072                 case -EACCES:
3073                         rtm->rtm_type = RTN_PROHIBIT;
3074                         break;
3075                 case -EAGAIN:
3076                         rtm->rtm_type = RTN_THROW;
3077                         break;
3078                 default:
3079                         rtm->rtm_type = RTN_UNREACHABLE;
3080                         break;
3081                 }
3082         }
3083         else if (rt->rt6i_flags & RTF_LOCAL)
3084                 rtm->rtm_type = RTN_LOCAL;
3085         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3086                 rtm->rtm_type = RTN_LOCAL;
3087         else
3088                 rtm->rtm_type = RTN_UNICAST;
3089         rtm->rtm_flags = 0;
3090         if (!netif_carrier_ok(rt->dst.dev)) {
3091                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3092                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3093                         rtm->rtm_flags |= RTNH_F_DEAD;
3094         }
3095         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3096         rtm->rtm_protocol = rt->rt6i_protocol;
3097         if (rt->rt6i_flags & RTF_DYNAMIC)
3098                 rtm->rtm_protocol = RTPROT_REDIRECT;
3099         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3100                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3101                         rtm->rtm_protocol = RTPROT_RA;
3102                 else
3103                         rtm->rtm_protocol = RTPROT_KERNEL;
3104         }
3105
3106         if (rt->rt6i_flags & RTF_CACHE)
3107                 rtm->rtm_flags |= RTM_F_CLONED;
3108
3109         if (dst) {
3110                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3111                         goto nla_put_failure;
3112                 rtm->rtm_dst_len = 128;
3113         } else if (rtm->rtm_dst_len)
3114                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3115                         goto nla_put_failure;
3116 #ifdef CONFIG_IPV6_SUBTREES
3117         if (src) {
3118                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3119                         goto nla_put_failure;
3120                 rtm->rtm_src_len = 128;
3121         } else if (rtm->rtm_src_len &&
3122                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3123                 goto nla_put_failure;
3124 #endif
3125         if (iif) {
3126 #ifdef CONFIG_IPV6_MROUTE
3127                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3128                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3129                         if (err <= 0) {
3130                                 if (!nowait) {
3131                                         if (err == 0)
3132                                                 return 0;
3133                                         goto nla_put_failure;
3134                                 } else {
3135                                         if (err == -EMSGSIZE)
3136                                                 goto nla_put_failure;
3137                                 }
3138                         }
3139                 } else
3140 #endif
3141                         if (nla_put_u32(skb, RTA_IIF, iif))
3142                                 goto nla_put_failure;
3143         } else if (dst) {
3144                 struct in6_addr saddr_buf;
3145                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3146                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3147                         goto nla_put_failure;
3148         }
3149
3150         if (rt->rt6i_prefsrc.plen) {
3151                 struct in6_addr saddr_buf;
3152                 saddr_buf = rt->rt6i_prefsrc.addr;
3153                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3154                         goto nla_put_failure;
3155         }
3156
3157         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3158         if (rt->rt6i_pmtu)
3159                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3160         if (rtnetlink_put_metrics(skb, metrics) < 0)
3161                 goto nla_put_failure;
3162
3163         if (rt->rt6i_flags & RTF_GATEWAY) {
3164                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3165                         goto nla_put_failure;
3166         }
3167
3168         if (rt->dst.dev &&
3169             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3170                 goto nla_put_failure;
3171         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3172                 goto nla_put_failure;
3173
3174         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3175
3176         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3177                 goto nla_put_failure;
3178
3179         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3180                 goto nla_put_failure;
3181
3182         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3183
3184         nlmsg_end(skb, nlh);
3185         return 0;
3186
3187 nla_put_failure:
3188         nlmsg_cancel(skb, nlh);
3189         return -EMSGSIZE;
3190 }
3191
3192 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3193 {
3194         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3195         int prefix;
3196
3197         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3198                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3199                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3200         } else
3201                 prefix = 0;
3202
3203         return rt6_fill_node(arg->net,
3204                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3205                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3206                      prefix, 0, NLM_F_MULTI);
3207 }
3208
3209 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3210 {
3211         struct net *net = sock_net(in_skb->sk);
3212         struct nlattr *tb[RTA_MAX+1];
3213         struct rt6_info *rt;
3214         struct sk_buff *skb;
3215         struct rtmsg *rtm;
3216         struct flowi6 fl6;
3217         int err, iif = 0, oif = 0;
3218
3219         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3220         if (err < 0)
3221                 goto errout;
3222
3223         err = -EINVAL;
3224         memset(&fl6, 0, sizeof(fl6));
3225
3226         if (tb[RTA_SRC]) {
3227                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3228                         goto errout;
3229
3230                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3231         }
3232
3233         if (tb[RTA_DST]) {
3234                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3235                         goto errout;
3236
3237                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3238         }
3239
3240         if (tb[RTA_IIF])
3241                 iif = nla_get_u32(tb[RTA_IIF]);
3242
3243         if (tb[RTA_OIF])
3244                 oif = nla_get_u32(tb[RTA_OIF]);
3245
3246         if (tb[RTA_MARK])
3247                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3248
3249         if (iif) {
3250                 struct net_device *dev;
3251                 int flags = 0;
3252
3253                 dev = __dev_get_by_index(net, iif);
3254                 if (!dev) {
3255                         err = -ENODEV;
3256                         goto errout;
3257                 }
3258
3259                 fl6.flowi6_iif = iif;
3260
3261                 if (!ipv6_addr_any(&fl6.saddr))
3262                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3263
3264                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3265                                                                flags);
3266         } else {
3267                 fl6.flowi6_oif = oif;
3268
3269                 if (netif_index_is_l3_master(net, oif)) {
3270                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3271                                            FLOWI_FLAG_SKIP_NH_OIF;
3272                 }
3273
3274                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3275         }
3276
3277         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3278         if (!skb) {
3279                 ip6_rt_put(rt);
3280                 err = -ENOBUFS;
3281                 goto errout;
3282         }
3283
3284         /* Reserve room for dummy headers, this skb can pass
3285            through good chunk of routing engine.
3286          */
3287         skb_reset_mac_header(skb);
3288         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3289
3290         skb_dst_set(skb, &rt->dst);
3291
3292         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3293                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3294                             nlh->nlmsg_seq, 0, 0, 0);
3295         if (err < 0) {
3296                 kfree_skb(skb);
3297                 goto errout;
3298         }
3299
3300         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3301 errout:
3302         return err;
3303 }
3304
3305 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3306                      unsigned int nlm_flags)
3307 {
3308         struct sk_buff *skb;
3309         struct net *net = info->nl_net;
3310         u32 seq;
3311         int err;
3312
3313         err = -ENOBUFS;
3314         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3315
3316         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3317         if (!skb)
3318                 goto errout;
3319
3320         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3321                                 event, info->portid, seq, 0, 0, nlm_flags);
3322         if (err < 0) {
3323                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3324                 WARN_ON(err == -EMSGSIZE);
3325                 kfree_skb(skb);
3326                 goto errout;
3327         }
3328         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3329                     info->nlh, gfp_any());
3330         return;
3331 errout:
3332         if (err < 0)
3333                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3334 }
3335
3336 static int ip6_route_dev_notify(struct notifier_block *this,
3337                                 unsigned long event, void *ptr)
3338 {
3339         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3340         struct net *net = dev_net(dev);
3341
3342         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3343                 net->ipv6.ip6_null_entry->dst.dev = dev;
3344                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3345 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3346                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3347                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3348                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3349                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3350 #endif
3351         }
3352
3353         return NOTIFY_OK;
3354 }
3355
3356 /*
3357  *      /proc
3358  */
3359
3360 #ifdef CONFIG_PROC_FS
3361
3362 static const struct file_operations ipv6_route_proc_fops = {
3363         .owner          = THIS_MODULE,
3364         .open           = ipv6_route_open,
3365         .read           = seq_read,
3366         .llseek         = seq_lseek,
3367         .release        = seq_release_net,
3368 };
3369
3370 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3371 {
3372         struct net *net = (struct net *)seq->private;
3373         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3374                    net->ipv6.rt6_stats->fib_nodes,
3375                    net->ipv6.rt6_stats->fib_route_nodes,
3376                    net->ipv6.rt6_stats->fib_rt_alloc,
3377                    net->ipv6.rt6_stats->fib_rt_entries,
3378                    net->ipv6.rt6_stats->fib_rt_cache,
3379                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3380                    net->ipv6.rt6_stats->fib_discarded_routes);
3381
3382         return 0;
3383 }
3384
3385 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3386 {
3387         return single_open_net(inode, file, rt6_stats_seq_show);
3388 }
3389
3390 static const struct file_operations rt6_stats_seq_fops = {
3391         .owner   = THIS_MODULE,
3392         .open    = rt6_stats_seq_open,
3393         .read    = seq_read,
3394         .llseek  = seq_lseek,
3395         .release = single_release_net,
3396 };
3397 #endif  /* CONFIG_PROC_FS */
3398
3399 #ifdef CONFIG_SYSCTL
3400
3401 static
3402 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3403                               void __user *buffer, size_t *lenp, loff_t *ppos)
3404 {
3405         struct net *net;
3406         int delay;
3407         if (!write)
3408                 return -EINVAL;
3409
3410         net = (struct net *)ctl->extra1;
3411         delay = net->ipv6.sysctl.flush_delay;
3412         proc_dointvec(ctl, write, buffer, lenp, ppos);
3413         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3414         return 0;
3415 }
3416
3417 struct ctl_table ipv6_route_table_template[] = {
3418         {
3419                 .procname       =       "flush",
3420                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3421                 .maxlen         =       sizeof(int),
3422                 .mode           =       0200,
3423                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3424         },
3425         {
3426                 .procname       =       "gc_thresh",
3427                 .data           =       &ip6_dst_ops_template.gc_thresh,
3428                 .maxlen         =       sizeof(int),
3429                 .mode           =       0644,
3430                 .proc_handler   =       proc_dointvec,
3431         },
3432         {
3433                 .procname       =       "max_size",
3434                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3435                 .maxlen         =       sizeof(int),
3436                 .mode           =       0644,
3437                 .proc_handler   =       proc_dointvec,
3438         },
3439         {
3440                 .procname       =       "gc_min_interval",
3441                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3442                 .maxlen         =       sizeof(int),
3443                 .mode           =       0644,
3444                 .proc_handler   =       proc_dointvec_jiffies,
3445         },
3446         {
3447                 .procname       =       "gc_timeout",
3448                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3449                 .maxlen         =       sizeof(int),
3450                 .mode           =       0644,
3451                 .proc_handler   =       proc_dointvec_jiffies,
3452         },
3453         {
3454                 .procname       =       "gc_interval",
3455                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3456                 .maxlen         =       sizeof(int),
3457                 .mode           =       0644,
3458                 .proc_handler   =       proc_dointvec_jiffies,
3459         },
3460         {
3461                 .procname       =       "gc_elasticity",
3462                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3463                 .maxlen         =       sizeof(int),
3464                 .mode           =       0644,
3465                 .proc_handler   =       proc_dointvec,
3466         },
3467         {
3468                 .procname       =       "mtu_expires",
3469                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3470                 .maxlen         =       sizeof(int),
3471                 .mode           =       0644,
3472                 .proc_handler   =       proc_dointvec_jiffies,
3473         },
3474         {
3475                 .procname       =       "min_adv_mss",
3476                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3477                 .maxlen         =       sizeof(int),
3478                 .mode           =       0644,
3479                 .proc_handler   =       proc_dointvec,
3480         },
3481         {
3482                 .procname       =       "gc_min_interval_ms",
3483                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3484                 .maxlen         =       sizeof(int),
3485                 .mode           =       0644,
3486                 .proc_handler   =       proc_dointvec_ms_jiffies,
3487         },
3488         { }
3489 };
3490
3491 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3492 {
3493         struct ctl_table *table;
3494
3495         table = kmemdup(ipv6_route_table_template,
3496                         sizeof(ipv6_route_table_template),
3497                         GFP_KERNEL);
3498
3499         if (table) {
3500                 table[0].data = &net->ipv6.sysctl.flush_delay;
3501                 table[0].extra1 = net;
3502                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3503                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3504                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3505                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3506                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3507                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3508                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3509                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3510                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3511
3512                 /* Don't export sysctls to unprivileged users */
3513                 if (net->user_ns != &init_user_ns)
3514                         table[0].procname = NULL;
3515         }
3516
3517         return table;
3518 }
3519 #endif
3520
3521 static int __net_init ip6_route_net_init(struct net *net)
3522 {
3523         int ret = -ENOMEM;
3524
3525         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3526                sizeof(net->ipv6.ip6_dst_ops));
3527
3528         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3529                 goto out_ip6_dst_ops;
3530
3531         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3532                                            sizeof(*net->ipv6.ip6_null_entry),
3533                                            GFP_KERNEL);
3534         if (!net->ipv6.ip6_null_entry)
3535                 goto out_ip6_dst_entries;
3536         net->ipv6.ip6_null_entry->dst.path =
3537                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3538         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3539         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3540                          ip6_template_metrics, true);
3541
3542 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3543         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3544                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3545                                                GFP_KERNEL);
3546         if (!net->ipv6.ip6_prohibit_entry)
3547                 goto out_ip6_null_entry;
3548         net->ipv6.ip6_prohibit_entry->dst.path =
3549                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3550         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3551         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3552                          ip6_template_metrics, true);
3553
3554         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3555                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3556                                                GFP_KERNEL);
3557         if (!net->ipv6.ip6_blk_hole_entry)
3558                 goto out_ip6_prohibit_entry;
3559         net->ipv6.ip6_blk_hole_entry->dst.path =
3560                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3561         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3562         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3563                          ip6_template_metrics, true);
3564 #endif
3565
3566         net->ipv6.sysctl.flush_delay = 0;
3567         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3568         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3569         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3570         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3571         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3572         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3573         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3574
3575         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3576
3577         ret = 0;
3578 out:
3579         return ret;
3580
3581 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3582 out_ip6_prohibit_entry:
3583         kfree(net->ipv6.ip6_prohibit_entry);
3584 out_ip6_null_entry:
3585         kfree(net->ipv6.ip6_null_entry);
3586 #endif
3587 out_ip6_dst_entries:
3588         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3589 out_ip6_dst_ops:
3590         goto out;
3591 }
3592
3593 static void __net_exit ip6_route_net_exit(struct net *net)
3594 {
3595         kfree(net->ipv6.ip6_null_entry);
3596 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3597         kfree(net->ipv6.ip6_prohibit_entry);
3598         kfree(net->ipv6.ip6_blk_hole_entry);
3599 #endif
3600         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3601 }
3602
3603 static int __net_init ip6_route_net_init_late(struct net *net)
3604 {
3605 #ifdef CONFIG_PROC_FS
3606         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3607         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3608 #endif
3609         return 0;
3610 }
3611
3612 static void __net_exit ip6_route_net_exit_late(struct net *net)
3613 {
3614 #ifdef CONFIG_PROC_FS
3615         remove_proc_entry("ipv6_route", net->proc_net);
3616         remove_proc_entry("rt6_stats", net->proc_net);
3617 #endif
3618 }
3619
3620 static struct pernet_operations ip6_route_net_ops = {
3621         .init = ip6_route_net_init,
3622         .exit = ip6_route_net_exit,
3623 };
3624
3625 static int __net_init ipv6_inetpeer_init(struct net *net)
3626 {
3627         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3628
3629         if (!bp)
3630                 return -ENOMEM;
3631         inet_peer_base_init(bp);
3632         net->ipv6.peers = bp;
3633         return 0;
3634 }
3635
3636 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3637 {
3638         struct inet_peer_base *bp = net->ipv6.peers;
3639
3640         net->ipv6.peers = NULL;
3641         inetpeer_invalidate_tree(bp);
3642         kfree(bp);
3643 }
3644
3645 static struct pernet_operations ipv6_inetpeer_ops = {
3646         .init   =       ipv6_inetpeer_init,
3647         .exit   =       ipv6_inetpeer_exit,
3648 };
3649
3650 static struct pernet_operations ip6_route_net_late_ops = {
3651         .init = ip6_route_net_init_late,
3652         .exit = ip6_route_net_exit_late,
3653 };
3654
3655 static struct notifier_block ip6_route_dev_notifier = {
3656         .notifier_call = ip6_route_dev_notify,
3657         .priority = 0,
3658 };
3659
3660 int __init ip6_route_init(void)
3661 {
3662         int ret;
3663         int cpu;
3664
3665         ret = -ENOMEM;
3666         ip6_dst_ops_template.kmem_cachep =
3667                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3668                                   SLAB_HWCACHE_ALIGN, NULL);
3669         if (!ip6_dst_ops_template.kmem_cachep)
3670                 goto out;
3671
3672         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3673         if (ret)
3674                 goto out_kmem_cache;
3675
3676         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3677         if (ret)
3678                 goto out_dst_entries;
3679
3680         ret = register_pernet_subsys(&ip6_route_net_ops);
3681         if (ret)
3682                 goto out_register_inetpeer;
3683
3684         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3685
3686         /* Registering of the loopback is done before this portion of code,
3687          * the loopback reference in rt6_info will not be taken, do it
3688          * manually for init_net */
3689         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3690         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3691   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3692         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3693         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3694         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3695         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3696   #endif
3697         ret = fib6_init();
3698         if (ret)
3699                 goto out_register_subsys;
3700
3701         ret = xfrm6_init();
3702         if (ret)
3703                 goto out_fib6_init;
3704
3705         ret = fib6_rules_init();
3706         if (ret)
3707                 goto xfrm6_init;
3708
3709         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3710         if (ret)
3711                 goto fib6_rules_init;
3712
3713         ret = -ENOBUFS;
3714         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3715             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3716             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3717                 goto out_register_late_subsys;
3718
3719         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3720         if (ret)
3721                 goto out_register_late_subsys;
3722
3723         for_each_possible_cpu(cpu) {
3724                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3725
3726                 INIT_LIST_HEAD(&ul->head);
3727                 spin_lock_init(&ul->lock);
3728         }
3729
3730 out:
3731         return ret;
3732
3733 out_register_late_subsys:
3734         unregister_pernet_subsys(&ip6_route_net_late_ops);
3735 fib6_rules_init:
3736         fib6_rules_cleanup();
3737 xfrm6_init:
3738         xfrm6_fini();
3739 out_fib6_init:
3740         fib6_gc_cleanup();
3741 out_register_subsys:
3742         unregister_pernet_subsys(&ip6_route_net_ops);
3743 out_register_inetpeer:
3744         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3745 out_dst_entries:
3746         dst_entries_destroy(&ip6_dst_blackhole_ops);
3747 out_kmem_cache:
3748         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3749         goto out;
3750 }
3751
3752 void ip6_route_cleanup(void)
3753 {
3754         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3755         unregister_pernet_subsys(&ip6_route_net_late_ops);
3756         fib6_rules_cleanup();
3757         xfrm6_fini();
3758         fib6_gc_cleanup();
3759         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3760         unregister_pernet_subsys(&ip6_route_net_ops);
3761         dst_entries_destroy(&ip6_dst_blackhole_ops);
3762         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3763 }