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         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
 851                 flags &= ~RT6_LOOKUP_F_IFACE;
 852
 853         read_lock_bh(&table->tb6_lock);
 854         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 855 restart:
 856         rt = fn->leaf;
 857         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 858         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 859                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 860         if (rt == net->ipv6.ip6_null_entry) {
 861                 fn = fib6_backtrack(fn, &fl6->saddr);
 862                 if (fn)
 863                         goto restart;
 864         }
 865         dst_use(&rt->dst, jiffies);
 866         read_unlock_bh(&table->tb6_lock);
 867         return rt;
 868
 869 }
 870
 871 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 872                                     int flags)
 873 {
 874         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 875 }
 876 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 877
 878 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 879                             const struct in6_addr *saddr, int oif, int strict)
 880 {
 881         struct flowi6 fl6 = {
 882                 .flowi6_oif = oif,
 883                 .daddr = *daddr,
 884         };
 885         struct dst_entry *dst;
 886         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 887
 888         if (saddr) {
 889                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 890                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 891         }
 892
 893         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 894         if (dst->error == 0)
 895                 return (struct rt6_info *) dst;
 896
 897         dst_release(dst);
 898
 899         return NULL;
 900 }
 901 EXPORT_SYMBOL(rt6_lookup);
 902
 903 /* ip6_ins_rt is called with FREE table->tb6_lock.
 904    It takes new route entry, the addition fails by any reason the
 905    route is freed. In any case, if caller does not hold it, it may
 906    be destroyed.
 907  */
 908
 909 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 910                         struct mx6_config *mxc)
 911 {
 912         int err;
 913         struct fib6_table *table;
 914
 915         table = rt->rt6i_table;
 916         write_lock_bh(&table->tb6_lock);
 917         err = fib6_add(&table->tb6_root, rt, info, mxc);
 918         write_unlock_bh(&table->tb6_lock);
 919
 920         return err;
 921 }
 922
 923 int ip6_ins_rt(struct rt6_info *rt)
 924 {
 925         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 926         struct mx6_config mxc = { .mx = NULL, };
 927
 928         return __ip6_ins_rt(rt, &info, &mxc);
 929 }
 930
 931 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 932                                            const struct in6_addr *daddr,
 933                                            const struct in6_addr *saddr)
 934 {
 935         struct rt6_info *rt;
 936
 937         /*
 938          *      Clone the route.
 939          */
 940
 941         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 942                 ort = (struct rt6_info *)ort->dst.from;
 943
 944         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 945
 946         if (!rt)
 947                 return NULL;
 948
 949         ip6_rt_copy_init(rt, ort);
 950         rt->rt6i_flags |= RTF_CACHE;
 951         rt->rt6i_metric = 0;
 952         rt->dst.flags |= DST_HOST;
 953         rt->rt6i_dst.addr = *daddr;
 954         rt->rt6i_dst.plen = 128;
 955
 956         if (!rt6_is_gw_or_nonexthop(ort)) {
 957                 if (ort->rt6i_dst.plen != 128 &&
 958                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 959                         rt->rt6i_flags |= RTF_ANYCAST;
 960 #ifdef CONFIG_IPV6_SUBTREES
 961                 if (rt->rt6i_src.plen && saddr) {
 962                         rt->rt6i_src.addr = *saddr;
 963                         rt->rt6i_src.plen = 128;
 964                 }
 965 #endif
 966         }
 967
 968         return rt;
 969 }
 970
 971 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 972 {
 973         struct rt6_info *pcpu_rt;
 974
 975         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 976                                   rt->dst.dev, rt->dst.flags);
 977
 978         if (!pcpu_rt)
 979                 return NULL;
 980         ip6_rt_copy_init(pcpu_rt, rt);
 981         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 982         pcpu_rt->rt6i_flags |= RTF_PCPU;
 983         return pcpu_rt;
 984 }
 985
 986 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 987 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 988 {
 989         struct rt6_info *pcpu_rt, **p;
 990
 991         p = this_cpu_ptr(rt->rt6i_pcpu);
 992         pcpu_rt = *p;
 993
 994         if (pcpu_rt) {
 995                 dst_hold(&pcpu_rt->dst);
 996                 rt6_dst_from_metrics_check(pcpu_rt);
 997         }
 998         return pcpu_rt;
 999 }
1000
1001 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1002 {
1003         struct fib6_table *table = rt->rt6i_table;
1004         struct rt6_info *pcpu_rt, *prev, **p;
1005
1006         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1007         if (!pcpu_rt) {
1008                 struct net *net = dev_net(rt->dst.dev);
1009
1010                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1011                 return net->ipv6.ip6_null_entry;
1012         }
1013
1014         read_lock_bh(&table->tb6_lock);
1015         if (rt->rt6i_pcpu) {
1016                 p = this_cpu_ptr(rt->rt6i_pcpu);
1017                 prev = cmpxchg(p, NULL, pcpu_rt);
1018                 if (prev) {
1019                         /* If someone did it before us, return prev instead */
1020                         dst_destroy(&pcpu_rt->dst);
1021                         pcpu_rt = prev;
1022                 }
1023         } else {
1024                 /* rt has been removed from the fib6 tree
1025                  * before we have a chance to acquire the read_lock.
1026                  * In this case, don't brother to create a pcpu rt
1027                  * since rt is going away anyway.  The next
1028                  * dst_check() will trigger a re-lookup.
1029                  */
1030                 dst_destroy(&pcpu_rt->dst);
1031                 pcpu_rt = rt;
1032         }
1033         dst_hold(&pcpu_rt->dst);
1034         rt6_dst_from_metrics_check(pcpu_rt);
1035         read_unlock_bh(&table->tb6_lock);
1036         return pcpu_rt;
1037 }
1038
1039 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1040                                       struct flowi6 *fl6, int flags)
1041 {
1042         struct fib6_node *fn, *saved_fn;
1043         struct rt6_info *rt;
1044         int strict = 0;
1045
1046         strict |= flags & RT6_LOOKUP_F_IFACE;
1047         if (net->ipv6.devconf_all->forwarding == 0)
1048                 strict |= RT6_LOOKUP_F_REACHABLE;
1049
1050         read_lock_bh(&table->tb6_lock);
1051
1052         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1053         saved_fn = fn;
1054
1055         if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
1056                 oif = 0;
1057
1058 redo_rt6_select:
1059         rt = rt6_select(fn, oif, strict);
1060         if (rt->rt6i_nsiblings)
1061                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1062         if (rt == net->ipv6.ip6_null_entry) {
1063                 fn = fib6_backtrack(fn, &fl6->saddr);
1064                 if (fn)
1065                         goto redo_rt6_select;
1066                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1067                         /* also consider unreachable route */
1068                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1069                         fn = saved_fn;
1070                         goto redo_rt6_select;
1071                 }
1072         }
1073
1074
1075         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1076                 dst_use(&rt->dst, jiffies);
1077                 read_unlock_bh(&table->tb6_lock);
1078
1079                 rt6_dst_from_metrics_check(rt);
1080                 return rt;
1081         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1082                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1083                 /* Create a RTF_CACHE clone which will not be
1084                  * owned by the fib6 tree.  It is for the special case where
1085                  * the daddr in the skb during the neighbor look-up is different
1086                  * from the fl6->daddr used to look-up route here.
1087                  */
1088
1089                 struct rt6_info *uncached_rt;
1090
1091                 dst_use(&rt->dst, jiffies);
1092                 read_unlock_bh(&table->tb6_lock);
1093
1094                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1095                 dst_release(&rt->dst);
1096
1097                 if (uncached_rt)
1098                         rt6_uncached_list_add(uncached_rt);
1099                 else
1100                         uncached_rt = net->ipv6.ip6_null_entry;
1101
1102                 dst_hold(&uncached_rt->dst);
1103                 return uncached_rt;
1104
1105         } else {
1106                 /* Get a percpu copy */
1107
1108                 struct rt6_info *pcpu_rt;
1109
1110                 rt->dst.lastuse = jiffies;
1111                 rt->dst.__use++;
1112                 pcpu_rt = rt6_get_pcpu_route(rt);
1113
1114                 if (pcpu_rt) {
1115                         read_unlock_bh(&table->tb6_lock);
1116                 } else {
1117                         /* We have to do the read_unlock first
1118                          * because rt6_make_pcpu_route() may trigger
1119                          * ip6_dst_gc() which will take the write_lock.
1120                          */
1121                         dst_hold(&rt->dst);
1122                         read_unlock_bh(&table->tb6_lock);
1123                         pcpu_rt = rt6_make_pcpu_route(rt);
1124                         dst_release(&rt->dst);
1125                 }
1126
1127                 return pcpu_rt;
1128
1129         }
1130 }
1131
1132 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1133                                             struct flowi6 *fl6, int flags)
1134 {
1135         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1136 }
1137
1138 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1139                                                 struct net_device *dev,
1140                                                 struct flowi6 *fl6, int flags)
1141 {
1142         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1143                 flags |= RT6_LOOKUP_F_IFACE;
1144
1145         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1146 }
1147
1148 void ip6_route_input(struct sk_buff *skb)
1149 {
1150         const struct ipv6hdr *iph = ipv6_hdr(skb);
1151         struct net *net = dev_net(skb->dev);
1152         int flags = RT6_LOOKUP_F_HAS_SADDR;
1153         struct ip_tunnel_info *tun_info;
1154         struct flowi6 fl6 = {
1155                 .flowi6_iif = l3mdev_fib_oif(skb->dev),
1156                 .daddr = iph->daddr,
1157                 .saddr = iph->saddr,
1158                 .flowlabel = ip6_flowinfo(iph),
1159                 .flowi6_mark = skb->mark,
1160                 .flowi6_proto = iph->nexthdr,
1161         };
1162
1163         tun_info = skb_tunnel_info(skb);
1164         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1165                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1166         skb_dst_drop(skb);
1167         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1168 }
1169
1170 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1171                                              struct flowi6 *fl6, int flags)
1172 {
1173         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1174 }
1175
1176 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
1177                                          struct flowi6 *fl6, int flags)
1178 {
1179         struct dst_entry *dst;
1180         bool any_src;
1181
1182         dst = l3mdev_rt6_dst_by_oif(net, fl6);
1183         if (dst)
1184                 return dst;
1185
1186         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1187
1188         any_src = ipv6_addr_any(&fl6->saddr);
1189         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
1190             (fl6->flowi6_oif && any_src))
1191                 flags |= RT6_LOOKUP_F_IFACE;
1192
1193         if (!any_src)
1194                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1195         else if (sk)
1196                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1197
1198         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1199 }
1200 EXPORT_SYMBOL_GPL(ip6_route_output_flags);
1201
1202 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1203 {
1204         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1205         struct dst_entry *new = NULL;
1206
1207         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1208         if (rt) {
1209                 rt6_info_init(rt);
1210
1211                 new = &rt->dst;
1212                 new->__use = 1;
1213                 new->input = dst_discard;
1214                 new->output = dst_discard_out;
1215
1216                 dst_copy_metrics(new, &ort->dst);
1217                 rt->rt6i_idev = ort->rt6i_idev;
1218                 if (rt->rt6i_idev)
1219                         in6_dev_hold(rt->rt6i_idev);
1220
1221                 rt->rt6i_gateway = ort->rt6i_gateway;
1222                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
1223                 rt->rt6i_metric = 0;
1224
1225                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1226 #ifdef CONFIG_IPV6_SUBTREES
1227                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1228 #endif
1229
1230                 dst_free(new);
1231         }
1232
1233         dst_release(dst_orig);
1234         return new ? new : ERR_PTR(-ENOMEM);
1235 }
1236
1237 /*
1238  *      Destination cache support functions
1239  */
1240
1241 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1242 {
1243         if (rt->dst.from &&
1244             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1245                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1246 }
1247
1248 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1249 {
1250         u32 rt_cookie;
1251
1252         if (!rt6_get_cookie_safe(rt, &rt_cookie) || rt_cookie != cookie)
1253                 return NULL;
1254
1255         if (rt6_check_expired(rt))
1256                 return NULL;
1257
1258         return &rt->dst;
1259 }
1260
1261 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1262 {
1263         if (!__rt6_check_expired(rt) &&
1264             rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1265             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1266                 return &rt->dst;
1267         else
1268                 return NULL;
1269 }
1270
1271 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1272 {
1273         struct rt6_info *rt;
1274
1275         rt = (struct rt6_info *) dst;
1276
1277         /* All IPV6 dsts are created with ->obsolete set to the value
1278          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1279          * into this function always.
1280          */
1281
1282         rt6_dst_from_metrics_check(rt);
1283
1284         if (rt->rt6i_flags & RTF_PCPU ||
1285             (unlikely(dst->flags & DST_NOCACHE) && rt->dst.from))
1286                 return rt6_dst_from_check(rt, cookie);
1287         else
1288                 return rt6_check(rt, cookie);
1289 }
1290
1291 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1292 {
1293         struct rt6_info *rt = (struct rt6_info *) dst;
1294
1295         if (rt) {
1296                 if (rt->rt6i_flags & RTF_CACHE) {
1297                         if (rt6_check_expired(rt)) {
1298                                 ip6_del_rt(rt);
1299                                 dst = NULL;
1300                         }
1301                 } else {
1302                         dst_release(dst);
1303                         dst = NULL;
1304                 }
1305         }
1306         return dst;
1307 }
1308
1309 static void ip6_link_failure(struct sk_buff *skb)
1310 {
1311         struct rt6_info *rt;
1312
1313         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1314
1315         rt = (struct rt6_info *) skb_dst(skb);
1316         if (rt) {
1317                 if (rt->rt6i_flags & RTF_CACHE) {
1318                         dst_hold(&rt->dst);
1319                         ip6_del_rt(rt);
1320                 } else {
1321                         struct fib6_node *fn;
1322
1323                         rcu_read_lock();
1324                         fn = rcu_dereference(rt->rt6i_node);
1325                         if (fn && (rt->rt6i_flags & RTF_DEFAULT))
1326                                 fn->fn_sernum = -1;
1327                         rcu_read_unlock();
1328                 }
1329         }
1330 }
1331
1332 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1333 {
1334         struct net *net = dev_net(rt->dst.dev);
1335
1336         rt->rt6i_flags |= RTF_MODIFIED;
1337         rt->rt6i_pmtu = mtu;
1338         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1339 }
1340
1341 static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
1342 {
1343         return !(rt->rt6i_flags & RTF_CACHE) &&
1344                 (rt->rt6i_flags & RTF_PCPU ||
1345                  rcu_access_pointer(rt->rt6i_node));
1346 }
1347
1348 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1349                                  const struct ipv6hdr *iph, u32 mtu)
1350 {
1351         struct rt6_info *rt6 = (struct rt6_info *)dst;
1352
1353         if (rt6->rt6i_flags & RTF_LOCAL)
1354                 return;
1355
1356         dst_confirm(dst);
1357         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1358         if (mtu >= dst_mtu(dst))
1359                 return;
1360
1361         if (!rt6_cache_allowed_for_pmtu(rt6)) {
1362                 rt6_do_update_pmtu(rt6, mtu);
1363         } else {
1364                 const struct in6_addr *daddr, *saddr;
1365                 struct rt6_info *nrt6;
1366
1367                 if (iph) {
1368                         daddr = &iph->daddr;
1369                         saddr = &iph->saddr;
1370                 } else if (sk) {
1371                         daddr = &sk->sk_v6_daddr;
1372                         saddr = &inet6_sk(sk)->saddr;
1373                 } else {
1374                         return;
1375                 }
1376                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1377                 if (nrt6) {
1378                         rt6_do_update_pmtu(nrt6, mtu);
1379
1380                         /* ip6_ins_rt(nrt6) will bump the
1381                          * rt6->rt6i_node->fn_sernum
1382                          * which will fail the next rt6_check() and
1383                          * invalidate the sk->sk_dst_cache.
1384                          */
1385                         ip6_ins_rt(nrt6);
1386                 }
1387         }
1388 }
1389
1390 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1391                                struct sk_buff *skb, u32 mtu)
1392 {
1393         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1394 }
1395
1396 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1397                      int oif, u32 mark, kuid_t uid)
1398 {
1399         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1400         struct dst_entry *dst;
1401         struct flowi6 fl6;
1402
1403         memset(&fl6, 0, sizeof(fl6));
1404         fl6.flowi6_oif = oif;
1405         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1406         fl6.daddr = iph->daddr;
1407         fl6.saddr = iph->saddr;
1408         fl6.flowlabel = ip6_flowinfo(iph);
1409         fl6.flowi6_uid = uid;
1410
1411         dst = ip6_route_output(net, NULL, &fl6);
1412         if (!dst->error)
1413                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1414         dst_release(dst);
1415 }
1416 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1417
1418 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1419 {
1420         int oif = sk->sk_bound_dev_if;
1421
1422         if (!oif && skb->dev)
1423                 oif = l3mdev_master_ifindex(skb->dev);
1424
1425         ip6_update_pmtu(skb, sock_net(sk), mtu, oif, sk->sk_mark, sk->sk_uid);
1426 }
1427 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1428
1429 /* Handle redirects */
1430 struct ip6rd_flowi {
1431         struct flowi6 fl6;
1432         struct in6_addr gateway;
1433 };
1434
1435 static struct rt6_info *__ip6_route_redirect(struct net *net,
1436                                              struct fib6_table *table,
1437                                              struct flowi6 *fl6,
1438                                              int flags)
1439 {
1440         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1441         struct rt6_info *rt;
1442         struct fib6_node *fn;
1443
1444         /* Get the "current" route for this destination and
1445          * check if the redirect has come from approriate router.
1446          *
1447          * RFC 4861 specifies that redirects should only be
1448          * accepted if they come from the nexthop to the target.
1449          * Due to the way the routes are chosen, this notion
1450          * is a bit fuzzy and one might need to check all possible
1451          * routes.
1452          */
1453
1454         read_lock_bh(&table->tb6_lock);
1455         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1456 restart:
1457         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1458                 if (rt6_check_expired(rt))
1459                         continue;
1460                 if (rt->dst.error)
1461                         break;
1462                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1463                         continue;
1464                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1465                         continue;
1466                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1467                         continue;
1468                 break;
1469         }
1470
1471         if (!rt)
1472                 rt = net->ipv6.ip6_null_entry;
1473         else if (rt->dst.error) {
1474                 rt = net->ipv6.ip6_null_entry;
1475                 goto out;
1476         }
1477
1478         if (rt == net->ipv6.ip6_null_entry) {
1479                 fn = fib6_backtrack(fn, &fl6->saddr);
1480                 if (fn)
1481                         goto restart;
1482         }
1483
1484 out:
1485         dst_hold(&rt->dst);
1486
1487         read_unlock_bh(&table->tb6_lock);
1488
1489         return rt;
1490 };
1491
1492 static struct dst_entry *ip6_route_redirect(struct net *net,
1493                                         const struct flowi6 *fl6,
1494                                         const struct in6_addr *gateway)
1495 {
1496         int flags = RT6_LOOKUP_F_HAS_SADDR;
1497         struct ip6rd_flowi rdfl;
1498
1499         rdfl.fl6 = *fl6;
1500         rdfl.gateway = *gateway;
1501
1502         return fib6_rule_lookup(net, &rdfl.fl6,
1503                                 flags, __ip6_route_redirect);
1504 }
1505
1506 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
1507                   kuid_t uid)
1508 {
1509         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1510         struct dst_entry *dst;
1511         struct flowi6 fl6;
1512
1513         memset(&fl6, 0, sizeof(fl6));
1514         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1515         fl6.flowi6_oif = oif;
1516         fl6.flowi6_mark = mark;
1517         fl6.daddr = iph->daddr;
1518         fl6.saddr = iph->saddr;
1519         fl6.flowlabel = ip6_flowinfo(iph);
1520         fl6.flowi6_uid = uid;
1521
1522         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1523         rt6_do_redirect(dst, NULL, skb);
1524         dst_release(dst);
1525 }
1526 EXPORT_SYMBOL_GPL(ip6_redirect);
1527
1528 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1529                             u32 mark)
1530 {
1531         const struct ipv6hdr *iph = ipv6_hdr(skb);
1532         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1533         struct dst_entry *dst;
1534         struct flowi6 fl6;
1535
1536         memset(&fl6, 0, sizeof(fl6));
1537         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1538         fl6.flowi6_oif = oif;
1539         fl6.flowi6_mark = mark;
1540         fl6.daddr = msg->dest;
1541         fl6.saddr = iph->daddr;
1542         fl6.flowi6_uid = sock_net_uid(net, NULL);
1543
1544         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1545         rt6_do_redirect(dst, NULL, skb);
1546         dst_release(dst);
1547 }
1548
1549 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1550 {
1551         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark,
1552                      sk->sk_uid);
1553 }
1554 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1555
1556 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1557 {
1558         struct net_device *dev = dst->dev;
1559         unsigned int mtu = dst_mtu(dst);
1560         struct net *net = dev_net(dev);
1561
1562         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1563
1564         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1565                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1566
1567         /*
1568          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1569          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1570          * IPV6_MAXPLEN is also valid and means: "any MSS,
1571          * rely only on pmtu discovery"
1572          */
1573         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1574                 mtu = IPV6_MAXPLEN;
1575         return mtu;
1576 }
1577
1578 static unsigned int ip6_mtu(const struct dst_entry *dst)
1579 {
1580         const struct rt6_info *rt = (const struct rt6_info *)dst;
1581         unsigned int mtu = rt->rt6i_pmtu;
1582         struct inet6_dev *idev;
1583
1584         if (mtu)
1585                 goto out;
1586
1587         mtu = dst_metric_raw(dst, RTAX_MTU);
1588         if (mtu)
1589                 goto out;
1590
1591         mtu = IPV6_MIN_MTU;
1592
1593         rcu_read_lock();
1594         idev = __in6_dev_get(dst->dev);
1595         if (idev)
1596                 mtu = idev->cnf.mtu6;
1597         rcu_read_unlock();
1598
1599 out:
1600         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1601 }
1602
1603 static struct dst_entry *icmp6_dst_gc_list;
1604 static DEFINE_SPINLOCK(icmp6_dst_lock);
1605
1606 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1607                                   struct flowi6 *fl6)
1608 {
1609         struct dst_entry *dst;
1610         struct rt6_info *rt;
1611         struct inet6_dev *idev = in6_dev_get(dev);
1612         struct net *net = dev_net(dev);
1613
1614         if (unlikely(!idev))
1615                 return ERR_PTR(-ENODEV);
1616
1617         rt = ip6_dst_alloc(net, dev, 0);
1618         if (unlikely(!rt)) {
1619                 in6_dev_put(idev);
1620                 dst = ERR_PTR(-ENOMEM);
1621                 goto out;
1622         }
1623
1624         rt->dst.flags |= DST_HOST;
1625         rt->dst.input = ip6_input;
1626         rt->dst.output  = ip6_output;
1627         atomic_set(&rt->dst.__refcnt, 1);
1628         rt->rt6i_gateway  = fl6->daddr;
1629         rt->rt6i_dst.addr = fl6->daddr;
1630         rt->rt6i_dst.plen = 128;
1631         rt->rt6i_idev     = idev;
1632         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1633
1634         spin_lock_bh(&icmp6_dst_lock);
1635         rt->dst.next = icmp6_dst_gc_list;
1636         icmp6_dst_gc_list = &rt->dst;
1637         spin_unlock_bh(&icmp6_dst_lock);
1638
1639         fib6_force_start_gc(net);
1640
1641         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1642
1643 out:
1644         return dst;
1645 }
1646
1647 int icmp6_dst_gc(void)
1648 {
1649         struct dst_entry *dst, **pprev;
1650         int more = 0;
1651
1652         spin_lock_bh(&icmp6_dst_lock);
1653         pprev = &icmp6_dst_gc_list;
1654
1655         while ((dst = *pprev) != NULL) {
1656                 if (!atomic_read(&dst->__refcnt)) {
1657                         *pprev = dst->next;
1658                         dst_free(dst);
1659                 } else {
1660                         pprev = &dst->next;
1661                         ++more;
1662                 }
1663         }
1664
1665         spin_unlock_bh(&icmp6_dst_lock);
1666
1667         return more;
1668 }
1669
1670 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1671                             void *arg)
1672 {
1673         struct dst_entry *dst, **pprev;
1674
1675         spin_lock_bh(&icmp6_dst_lock);
1676         pprev = &icmp6_dst_gc_list;
1677         while ((dst = *pprev) != NULL) {
1678                 struct rt6_info *rt = (struct rt6_info *) dst;
1679                 if (func(rt, arg)) {
1680                         *pprev = dst->next;
1681                         dst_free(dst);
1682                 } else {
1683                         pprev = &dst->next;
1684                 }
1685         }
1686         spin_unlock_bh(&icmp6_dst_lock);
1687 }
1688
1689 static int ip6_dst_gc(struct dst_ops *ops)
1690 {
1691         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1692         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1693         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1694         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1695         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1696         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1697         int entries;
1698
1699         entries = dst_entries_get_fast(ops);
1700         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1701             entries <= rt_max_size)
1702                 goto out;
1703
1704         net->ipv6.ip6_rt_gc_expire++;
1705         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1706         entries = dst_entries_get_slow(ops);
1707         if (entries < ops->gc_thresh)
1708                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1709 out:
1710         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1711         return entries > rt_max_size;
1712 }
1713
1714 static int ip6_convert_metrics(struct mx6_config *mxc,
1715                                const struct fib6_config *cfg)
1716 {
1717         bool ecn_ca = false;
1718         struct nlattr *nla;
1719         int remaining;
1720         u32 *mp;
1721
1722         if (!cfg->fc_mx)
1723                 return 0;
1724
1725         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1726         if (unlikely(!mp))
1727                 return -ENOMEM;
1728
1729         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1730                 int type = nla_type(nla);
1731                 u32 val;
1732
1733                 if (!type)
1734                         continue;
1735                 if (unlikely(type > RTAX_MAX))
1736                         goto err;
1737
1738                 if (type == RTAX_CC_ALGO) {
1739                         char tmp[TCP_CA_NAME_MAX];
1740
1741                         nla_strlcpy(tmp, nla, sizeof(tmp));
1742                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1743                         if (val == TCP_CA_UNSPEC)
1744                                 goto err;
1745                 } else {
1746                         val = nla_get_u32(nla);
1747                 }
1748                 if (type == RTAX_HOPLIMIT && val > 255)
1749                         val = 255;
1750                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1751                         goto err;
1752
1753                 mp[type - 1] = val;
1754                 __set_bit(type - 1, mxc->mx_valid);
1755         }
1756
1757         if (ecn_ca) {
1758                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1759                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1760         }
1761
1762         mxc->mx = mp;
1763         return 0;
1764  err:
1765         kfree(mp);
1766         return -EINVAL;
1767 }
1768
1769 static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg)
1770 {
1771         struct net *net = cfg->fc_nlinfo.nl_net;
1772         struct rt6_info *rt = NULL;
1773         struct net_device *dev = NULL;
1774         struct inet6_dev *idev = NULL;
1775         struct fib6_table *table;
1776         int addr_type;
1777         int err = -EINVAL;
1778
1779         /* RTF_PCPU is an internal flag; can not be set by userspace */
1780         if (cfg->fc_flags & RTF_PCPU)
1781                 goto out;
1782
1783         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1784                 goto out;
1785 #ifndef CONFIG_IPV6_SUBTREES
1786         if (cfg->fc_src_len)
1787                 goto out;
1788 #endif
1789         if (cfg->fc_ifindex) {
1790                 err = -ENODEV;
1791                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1792                 if (!dev)
1793                         goto out;
1794                 idev = in6_dev_get(dev);
1795                 if (!idev)
1796                         goto out;
1797         }
1798
1799         if (cfg->fc_metric == 0)
1800                 cfg->fc_metric = IP6_RT_PRIO_USER;
1801
1802         err = -ENOBUFS;
1803         if (cfg->fc_nlinfo.nlh &&
1804             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1805                 table = fib6_get_table(net, cfg->fc_table);
1806                 if (!table) {
1807                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1808                         table = fib6_new_table(net, cfg->fc_table);
1809                 }
1810         } else {
1811                 table = fib6_new_table(net, cfg->fc_table);
1812         }
1813
1814         if (!table)
1815                 goto out;
1816
1817         rt = ip6_dst_alloc(net, NULL,
1818                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1819
1820         if (!rt) {
1821                 err = -ENOMEM;
1822                 goto out;
1823         }
1824
1825         if (cfg->fc_flags & RTF_EXPIRES)
1826                 rt6_set_expires(rt, jiffies +
1827                                 clock_t_to_jiffies(cfg->fc_expires));
1828         else
1829                 rt6_clean_expires(rt);
1830
1831         if (cfg->fc_protocol == RTPROT_UNSPEC)
1832                 cfg->fc_protocol = RTPROT_BOOT;
1833         rt->rt6i_protocol = cfg->fc_protocol;
1834
1835         addr_type = ipv6_addr_type(&cfg->fc_dst);
1836
1837         if (addr_type & IPV6_ADDR_MULTICAST)
1838                 rt->dst.input = ip6_mc_input;
1839         else if (cfg->fc_flags & RTF_LOCAL)
1840                 rt->dst.input = ip6_input;
1841         else
1842                 rt->dst.input = ip6_forward;
1843
1844         rt->dst.output = ip6_output;
1845
1846         if (cfg->fc_encap) {
1847                 struct lwtunnel_state *lwtstate;
1848
1849                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1850                                            cfg->fc_encap, AF_INET6, cfg,
1851                                            &lwtstate);
1852                 if (err)
1853                         goto out;
1854                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1855                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1856                         rt->dst.lwtstate->orig_output = rt->dst.output;
1857                         rt->dst.output = lwtunnel_output;
1858                 }
1859                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1860                         rt->dst.lwtstate->orig_input = rt->dst.input;
1861                         rt->dst.input = lwtunnel_input;
1862                 }
1863         }
1864
1865         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1866         rt->rt6i_dst.plen = cfg->fc_dst_len;
1867         if (rt->rt6i_dst.plen == 128)
1868                 rt->dst.flags |= DST_HOST;
1869
1870 #ifdef CONFIG_IPV6_SUBTREES
1871         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1872         rt->rt6i_src.plen = cfg->fc_src_len;
1873 #endif
1874
1875         rt->rt6i_metric = cfg->fc_metric;
1876
1877         /* We cannot add true routes via loopback here,
1878            they would result in kernel looping; promote them to reject routes
1879          */
1880         if ((cfg->fc_flags & RTF_REJECT) ||
1881             (dev && (dev->flags & IFF_LOOPBACK) &&
1882              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1883              !(cfg->fc_flags & RTF_LOCAL))) {
1884                 /* hold loopback dev/idev if we haven't done so. */
1885                 if (dev != net->loopback_dev) {
1886                         if (dev) {
1887                                 dev_put(dev);
1888                                 in6_dev_put(idev);
1889                         }
1890                         dev = net->loopback_dev;
1891                         dev_hold(dev);
1892                         idev = in6_dev_get(dev);
1893                         if (!idev) {
1894                                 err = -ENODEV;
1895                                 goto out;
1896                         }
1897                 }
1898                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1899                 switch (cfg->fc_type) {
1900                 case RTN_BLACKHOLE:
1901                         rt->dst.error = -EINVAL;
1902                         rt->dst.output = dst_discard_out;
1903                         rt->dst.input = dst_discard;
1904                         break;
1905                 case RTN_PROHIBIT:
1906                         rt->dst.error = -EACCES;
1907                         rt->dst.output = ip6_pkt_prohibit_out;
1908                         rt->dst.input = ip6_pkt_prohibit;
1909                         break;
1910                 case RTN_THROW:
1911                 case RTN_UNREACHABLE:
1912                 default:
1913                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1914                                         : (cfg->fc_type == RTN_UNREACHABLE)
1915                                         ? -EHOSTUNREACH : -ENETUNREACH;
1916                         rt->dst.output = ip6_pkt_discard_out;
1917                         rt->dst.input = ip6_pkt_discard;
1918                         break;
1919                 }
1920                 goto install_route;
1921         }
1922
1923         if (cfg->fc_flags & RTF_GATEWAY) {
1924                 const struct in6_addr *gw_addr;
1925                 int gwa_type;
1926
1927                 gw_addr = &cfg->fc_gateway;
1928                 gwa_type = ipv6_addr_type(gw_addr);
1929
1930                 /* if gw_addr is local we will fail to detect this in case
1931                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1932                  * will return already-added prefix route via interface that
1933                  * prefix route was assigned to, which might be non-loopback.
1934                  */
1935                 err = -EINVAL;
1936                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1937                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1938                                             dev : NULL, 0, 0))
1939                         goto out;
1940
1941                 rt->rt6i_gateway = *gw_addr;
1942
1943                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1944                         struct rt6_info *grt;
1945
1946                         /* IPv6 strictly inhibits using not link-local
1947                            addresses as nexthop address.
1948                            Otherwise, router will not able to send redirects.
1949                            It is very good, but in some (rare!) circumstances
1950                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1951                            some exceptions. --ANK
1952                          */
1953                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1954                                 goto out;
1955
1956                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1957
1958                         err = -EHOSTUNREACH;
1959                         if (!grt)
1960                                 goto out;
1961                         if (dev) {
1962                                 if (dev != grt->dst.dev) {
1963                                         ip6_rt_put(grt);
1964                                         goto out;
1965                                 }
1966                         } else {
1967                                 dev = grt->dst.dev;
1968                                 idev = grt->rt6i_idev;
1969                                 dev_hold(dev);
1970                                 in6_dev_hold(grt->rt6i_idev);
1971                         }
1972                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1973                                 err = 0;
1974                         ip6_rt_put(grt);
1975
1976                         if (err)
1977                                 goto out;
1978                 }
1979                 err = -EINVAL;
1980                 if (!dev || (dev->flags & IFF_LOOPBACK))
1981                         goto out;
1982         }
1983
1984         err = -ENODEV;
1985         if (!dev)
1986                 goto out;
1987
1988         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1989                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1990                         err = -EINVAL;
1991                         goto out;
1992                 }
1993                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1994                 rt->rt6i_prefsrc.plen = 128;
1995         } else
1996                 rt->rt6i_prefsrc.plen = 0;
1997
1998         rt->rt6i_flags = cfg->fc_flags;
1999
2000 install_route:
2001         rt->dst.dev = dev;
2002         rt->rt6i_idev = idev;
2003         rt->rt6i_table = table;
2004
2005         cfg->fc_nlinfo.nl_net = dev_net(dev);
2006
2007         return rt;
2008 out:
2009         if (dev)
2010                 dev_put(dev);
2011         if (idev)
2012                 in6_dev_put(idev);
2013         if (rt)
2014                 dst_free(&rt->dst);
2015
2016         return ERR_PTR(err);
2017 }
2018
2019 int ip6_route_add(struct fib6_config *cfg)
2020 {
2021         struct mx6_config mxc = { .mx = NULL, };
2022         struct rt6_info *rt;
2023         int err;
2024
2025         rt = ip6_route_info_create(cfg);
2026         if (IS_ERR(rt)) {
2027                 err = PTR_ERR(rt);
2028                 rt = NULL;
2029                 goto out;
2030         }
2031
2032         err = ip6_convert_metrics(&mxc, cfg);
2033         if (err)
2034                 goto out;
2035
2036         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2037
2038         kfree(mxc.mx);
2039
2040         return err;
2041 out:
2042         if (rt)
2043                 dst_free(&rt->dst);
2044
2045         return err;
2046 }
2047
2048 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2049 {
2050         int err;
2051         struct fib6_table *table;
2052         struct net *net = dev_net(rt->dst.dev);
2053
2054         if (rt == net->ipv6.ip6_null_entry ||
2055             rt->dst.flags & DST_NOCACHE) {
2056                 err = -ENOENT;
2057                 goto out;
2058         }
2059
2060         table = rt->rt6i_table;
2061         write_lock_bh(&table->tb6_lock);
2062         err = fib6_del(rt, info);
2063         write_unlock_bh(&table->tb6_lock);
2064
2065 out:
2066         ip6_rt_put(rt);
2067         return err;
2068 }
2069
2070 int ip6_del_rt(struct rt6_info *rt)
2071 {
2072         struct nl_info info = {
2073                 .nl_net = dev_net(rt->dst.dev),
2074         };
2075         return __ip6_del_rt(rt, &info);
2076 }
2077
2078 static int ip6_route_del(struct fib6_config *cfg)
2079 {
2080         struct fib6_table *table;
2081         struct fib6_node *fn;
2082         struct rt6_info *rt;
2083         int err = -ESRCH;
2084
2085         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2086         if (!table)
2087                 return err;
2088
2089         read_lock_bh(&table->tb6_lock);
2090
2091         fn = fib6_locate(&table->tb6_root,
2092                          &cfg->fc_dst, cfg->fc_dst_len,
2093                          &cfg->fc_src, cfg->fc_src_len);
2094
2095         if (fn) {
2096                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2097                         if ((rt->rt6i_flags & RTF_CACHE) &&
2098                             !(cfg->fc_flags & RTF_CACHE))
2099                                 continue;
2100                         if (cfg->fc_ifindex &&
2101                             (!rt->dst.dev ||
2102                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2103                                 continue;
2104                         if (cfg->fc_flags & RTF_GATEWAY &&
2105                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2106                                 continue;
2107                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2108                                 continue;
2109                         if (cfg->fc_protocol && cfg->fc_protocol != rt->rt6i_protocol)
2110                                 continue;
2111                         dst_hold(&rt->dst);
2112                         read_unlock_bh(&table->tb6_lock);
2113
2114                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2115                 }
2116         }
2117         read_unlock_bh(&table->tb6_lock);
2118
2119         return err;
2120 }
2121
2122 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2123 {
2124         struct netevent_redirect netevent;
2125         struct rt6_info *rt, *nrt = NULL;
2126         struct ndisc_options ndopts;
2127         struct inet6_dev *in6_dev;
2128         struct neighbour *neigh;
2129         struct rd_msg *msg;
2130         int optlen, on_link;
2131         u8 *lladdr;
2132
2133         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2134         optlen -= sizeof(*msg);
2135
2136         if (optlen < 0) {
2137                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2138                 return;
2139         }
2140
2141         msg = (struct rd_msg *)icmp6_hdr(skb);
2142
2143         if (ipv6_addr_is_multicast(&msg->dest)) {
2144                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2145                 return;
2146         }
2147
2148         on_link = 0;
2149         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2150                 on_link = 1;
2151         } else if (ipv6_addr_type(&msg->target) !=
2152                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2153                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2154                 return;
2155         }
2156
2157         in6_dev = __in6_dev_get(skb->dev);
2158         if (!in6_dev)
2159                 return;
2160         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2161                 return;
2162
2163         /* RFC2461 8.1:
2164          *      The IP source address of the Redirect MUST be the same as the current
2165          *      first-hop router for the specified ICMP Destination Address.
2166          */
2167
2168         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2169                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2170                 return;
2171         }
2172
2173         lladdr = NULL;
2174         if (ndopts.nd_opts_tgt_lladdr) {
2175                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2176                                              skb->dev);
2177                 if (!lladdr) {
2178                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2179                         return;
2180                 }
2181         }
2182
2183         rt = (struct rt6_info *) dst;
2184         if (rt->rt6i_flags & RTF_REJECT) {
2185                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2186                 return;
2187         }
2188
2189         /* Redirect received -> path was valid.
2190          * Look, redirects are sent only in response to data packets,
2191          * so that this nexthop apparently is reachable. --ANK
2192          */
2193         dst_confirm(&rt->dst);
2194
2195         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2196         if (!neigh)
2197                 return;
2198
2199         /*
2200          *      We have finally decided to accept it.
2201          */
2202
2203         neigh_update(neigh, lladdr, NUD_STALE,
2204                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2205                      NEIGH_UPDATE_F_OVERRIDE|
2206                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2207                                      NEIGH_UPDATE_F_ISROUTER))
2208                      );
2209
2210         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2211         if (!nrt)
2212                 goto out;
2213
2214         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2215         if (on_link)
2216                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2217
2218         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2219
2220         if (ip6_ins_rt(nrt))
2221                 goto out;
2222
2223         netevent.old = &rt->dst;
2224         netevent.new = &nrt->dst;
2225         netevent.daddr = &msg->dest;
2226         netevent.neigh = neigh;
2227         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2228
2229         if (rt->rt6i_flags & RTF_CACHE) {
2230                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2231                 ip6_del_rt(rt);
2232         }
2233
2234 out:
2235         neigh_release(neigh);
2236 }
2237
2238 /*
2239  *      Misc support functions
2240  */
2241
2242 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2243 {
2244         BUG_ON(from->dst.from);
2245
2246         rt->rt6i_flags &= ~RTF_EXPIRES;
2247         dst_hold(&from->dst);
2248         rt->dst.from = &from->dst;
2249         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2250 }
2251
2252 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2253 {
2254         rt->dst.input = ort->dst.input;
2255         rt->dst.output = ort->dst.output;
2256         rt->rt6i_dst = ort->rt6i_dst;
2257         rt->dst.error = ort->dst.error;
2258         rt->rt6i_idev = ort->rt6i_idev;
2259         if (rt->rt6i_idev)
2260                 in6_dev_hold(rt->rt6i_idev);
2261         rt->dst.lastuse = jiffies;
2262         rt->rt6i_gateway = ort->rt6i_gateway;
2263         rt->rt6i_flags = ort->rt6i_flags;
2264         rt6_set_from(rt, ort);
2265         rt->rt6i_metric = ort->rt6i_metric;
2266 #ifdef CONFIG_IPV6_SUBTREES
2267         rt->rt6i_src = ort->rt6i_src;
2268 #endif
2269         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2270         rt->rt6i_table = ort->rt6i_table;
2271         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2272 }
2273
2274 #ifdef CONFIG_IPV6_ROUTE_INFO
2275 static struct rt6_info *rt6_get_route_info(struct net_device *dev,
2276                                            const struct in6_addr *prefix, int prefixlen,
2277                                            const struct in6_addr *gwaddr)
2278 {
2279         struct fib6_node *fn;
2280         struct rt6_info *rt = NULL;
2281         struct fib6_table *table;
2282
2283         table = fib6_get_table(dev_net(dev),
2284                                addrconf_rt_table(dev, RT6_TABLE_INFO));
2285         if (!table)
2286                 return NULL;
2287
2288         read_lock_bh(&table->tb6_lock);
2289         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2290         if (!fn)
2291                 goto out;
2292
2293         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2294                 if (rt->dst.dev->ifindex != dev->ifindex)
2295                         continue;
2296                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2297                         continue;
2298                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2299                         continue;
2300                 dst_hold(&rt->dst);
2301                 break;
2302         }
2303 out:
2304         read_unlock_bh(&table->tb6_lock);
2305         return rt;
2306 }
2307
2308 static struct rt6_info *rt6_add_route_info(struct net_device *dev,
2309                                            const struct in6_addr *prefix, int prefixlen,
2310                                            const struct in6_addr *gwaddr, unsigned int pref)
2311 {
2312         struct fib6_config cfg = {
2313                 .fc_metric      = IP6_RT_PRIO_USER,
2314                 .fc_ifindex     = dev->ifindex,
2315                 .fc_dst_len     = prefixlen,
2316                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2317                                   RTF_UP | RTF_PREF(pref),
2318                 .fc_nlinfo.portid = 0,
2319                 .fc_nlinfo.nlh = NULL,
2320                 .fc_nlinfo.nl_net = dev_net(dev),
2321         };
2322
2323         cfg.fc_table = l3mdev_fib_table_by_index(dev_net(dev), dev->ifindex) ? : addrconf_rt_table(dev, RT6_TABLE_INFO);
2324         cfg.fc_dst = *prefix;
2325         cfg.fc_gateway = *gwaddr;
2326
2327         /* We should treat it as a default route if prefix length is 0. */
2328         if (!prefixlen)
2329                 cfg.fc_flags |= RTF_DEFAULT;
2330
2331         ip6_route_add(&cfg);
2332
2333         return rt6_get_route_info(dev, prefix, prefixlen, gwaddr);
2334 }
2335 #endif
2336
2337 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2338 {
2339         struct rt6_info *rt;
2340         struct fib6_table *table;
2341
2342         table = fib6_get_table(dev_net(dev),
2343                                addrconf_rt_table(dev, RT6_TABLE_MAIN));
2344         if (!table)
2345                 return NULL;
2346
2347         read_lock_bh(&table->tb6_lock);
2348         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2349                 if (dev == rt->dst.dev &&
2350                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2351                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2352                         break;
2353         }
2354         if (rt)
2355                 dst_hold(&rt->dst);
2356         read_unlock_bh(&table->tb6_lock);
2357         return rt;
2358 }
2359
2360 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2361                                      struct net_device *dev,
2362                                      unsigned int pref)
2363 {
2364         struct fib6_config cfg = {
2365                 .fc_table       = l3mdev_fib_table(dev) ? : addrconf_rt_table(dev, RT6_TABLE_DFLT),
2366                 .fc_metric      = IP6_RT_PRIO_USER,
2367                 .fc_ifindex     = dev->ifindex,
2368                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2369                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2370                 .fc_nlinfo.portid = 0,
2371                 .fc_nlinfo.nlh = NULL,
2372                 .fc_nlinfo.nl_net = dev_net(dev),
2373         };
2374
2375         cfg.fc_gateway = *gwaddr;
2376
2377         ip6_route_add(&cfg);
2378
2379         return rt6_get_dflt_router(gwaddr, dev);
2380 }
2381
2382
2383 int rt6_addrconf_purge(struct rt6_info *rt, void *arg) {
2384         if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2385             (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2))
2386                 return -1;
2387         return 0;
2388 }
2389
2390 void rt6_purge_dflt_routers(struct net *net)
2391 {
2392         fib6_clean_all(net, rt6_addrconf_purge, NULL);
2393 }
2394
2395 static void rtmsg_to_fib6_config(struct net *net,
2396                                  struct in6_rtmsg *rtmsg,
2397                                  struct fib6_config *cfg)
2398 {
2399         memset(cfg, 0, sizeof(*cfg));
2400
2401         cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
2402                          : RT6_TABLE_MAIN;
2403         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2404         cfg->fc_metric = rtmsg->rtmsg_metric;
2405         cfg->fc_expires = rtmsg->rtmsg_info;
2406         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2407         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2408         cfg->fc_flags = rtmsg->rtmsg_flags;
2409
2410         cfg->fc_nlinfo.nl_net = net;
2411
2412         cfg->fc_dst = rtmsg->rtmsg_dst;
2413         cfg->fc_src = rtmsg->rtmsg_src;
2414         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2415 }
2416
2417 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2418 {
2419         struct fib6_config cfg;
2420         struct in6_rtmsg rtmsg;
2421         int err;
2422
2423         switch (cmd) {
2424         case SIOCADDRT:         /* Add a route */
2425         case SIOCDELRT:         /* Delete a route */
2426                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2427                         return -EPERM;
2428                 err = copy_from_user(&rtmsg, arg,
2429                                      sizeof(struct in6_rtmsg));
2430                 if (err)
2431                         return -EFAULT;
2432
2433                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2434
2435                 rtnl_lock();
2436                 switch (cmd) {
2437                 case SIOCADDRT:
2438                         err = ip6_route_add(&cfg);
2439                         break;
2440                 case SIOCDELRT:
2441                         err = ip6_route_del(&cfg);
2442                         break;
2443                 default:
2444                         err = -EINVAL;
2445                 }
2446                 rtnl_unlock();
2447
2448                 return err;
2449         }
2450
2451         return -EINVAL;
2452 }
2453
2454 /*
2455  *      Drop the packet on the floor
2456  */
2457
2458 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2459 {
2460         int type;
2461         struct dst_entry *dst = skb_dst(skb);
2462         switch (ipstats_mib_noroutes) {
2463         case IPSTATS_MIB_INNOROUTES:
2464                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2465                 if (type == IPV6_ADDR_ANY) {
2466                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2467                                       IPSTATS_MIB_INADDRERRORS);
2468                         break;
2469                 }
2470                 /* FALLTHROUGH */
2471         case IPSTATS_MIB_OUTNOROUTES:
2472                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2473                               ipstats_mib_noroutes);
2474                 break;
2475         }
2476         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2477         kfree_skb(skb);
2478         return 0;
2479 }
2480
2481 static int ip6_pkt_discard(struct sk_buff *skb)
2482 {
2483         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2484 }
2485
2486 static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2487 {
2488         skb->dev = skb_dst(skb)->dev;
2489         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2490 }
2491
2492 static int ip6_pkt_prohibit(struct sk_buff *skb)
2493 {
2494         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2495 }
2496
2497 static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
2498 {
2499         skb->dev = skb_dst(skb)->dev;
2500         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2501 }
2502
2503 /*
2504  *      Allocate a dst for local (unicast / anycast) address.
2505  */
2506
2507 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2508                                     const struct in6_addr *addr,
2509                                     bool anycast)
2510 {
2511         u32 tb_id;
2512         struct net *net = dev_net(idev->dev);
2513         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2514                                             DST_NOCOUNT);
2515         if (!rt)
2516                 return ERR_PTR(-ENOMEM);
2517
2518         in6_dev_hold(idev);
2519
2520         rt->dst.flags |= DST_HOST;
2521         rt->dst.input = ip6_input;
2522         rt->dst.output = ip6_output;
2523         rt->rt6i_idev = idev;
2524
2525         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2526         if (anycast)
2527                 rt->rt6i_flags |= RTF_ANYCAST;
2528         else
2529                 rt->rt6i_flags |= RTF_LOCAL;
2530
2531         rt->rt6i_gateway  = *addr;
2532         rt->rt6i_dst.addr = *addr;
2533         rt->rt6i_dst.plen = 128;
2534         tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
2535         rt->rt6i_table = fib6_get_table(net, tb_id);
2536         rt->dst.flags |= DST_NOCACHE;
2537
2538         atomic_set(&rt->dst.__refcnt, 1);
2539
2540         return rt;
2541 }
2542
2543 int ip6_route_get_saddr(struct net *net,
2544                         struct rt6_info *rt,
2545                         const struct in6_addr *daddr,
2546                         unsigned int prefs,
2547                         struct in6_addr *saddr)
2548 {
2549         struct inet6_dev *idev =
2550                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2551         int err = 0;
2552         if (rt && rt->rt6i_prefsrc.plen)
2553                 *saddr = rt->rt6i_prefsrc.addr;
2554         else
2555                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2556                                          daddr, prefs, saddr);
2557         return err;
2558 }
2559
2560 /* remove deleted ip from prefsrc entries */
2561 struct arg_dev_net_ip {
2562         struct net_device *dev;
2563         struct net *net;
2564         struct in6_addr *addr;
2565 };
2566
2567 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2568 {
2569         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2570         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2571         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2572
2573         if (((void *)rt->dst.dev == dev || !dev) &&
2574             rt != net->ipv6.ip6_null_entry &&
2575             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2576                 /* remove prefsrc entry */
2577                 rt->rt6i_prefsrc.plen = 0;
2578         }
2579         return 0;
2580 }
2581
2582 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2583 {
2584         struct net *net = dev_net(ifp->idev->dev);
2585         struct arg_dev_net_ip adni = {
2586                 .dev = ifp->idev->dev,
2587                 .net = net,
2588                 .addr = &ifp->addr,
2589         };
2590         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2591 }
2592
2593 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2594 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2595
2596 /* Remove routers and update dst entries when gateway turn into host. */
2597 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2598 {
2599         struct in6_addr *gateway = (struct in6_addr *)arg;
2600
2601         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2602              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2603              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2604                 return -1;
2605         }
2606         return 0;
2607 }
2608
2609 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2610 {
2611         fib6_clean_all(net, fib6_clean_tohost, gateway);
2612 }
2613
2614 struct arg_dev_net {
2615         struct net_device *dev;
2616         struct net *net;
2617 };
2618
2619 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2620 {
2621         const struct arg_dev_net *adn = arg;
2622         const struct net_device *dev = adn->dev;
2623
2624         if ((rt->dst.dev == dev || !dev) &&
2625             rt != adn->net->ipv6.ip6_null_entry)
2626                 return -1;
2627
2628         return 0;
2629 }
2630
2631 void rt6_ifdown(struct net *net, struct net_device *dev)
2632 {
2633         struct arg_dev_net adn = {
2634                 .dev = dev,
2635                 .net = net,
2636         };
2637
2638         fib6_clean_all(net, fib6_ifdown, &adn);
2639         icmp6_clean_all(fib6_ifdown, &adn);
2640         if (dev)
2641                 rt6_uncached_list_flush_dev(net, dev);
2642 }
2643
2644 struct rt6_mtu_change_arg {
2645         struct net_device *dev;
2646         unsigned int mtu;
2647 };
2648
2649 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2650 {
2651         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2652         struct inet6_dev *idev;
2653
2654         /* In IPv6 pmtu discovery is not optional,
2655            so that RTAX_MTU lock cannot disable it.
2656            We still use this lock to block changes
2657            caused by addrconf/ndisc.
2658         */
2659
2660         idev = __in6_dev_get(arg->dev);
2661         if (!idev)
2662                 return 0;
2663
2664         /* For administrative MTU increase, there is no way to discover
2665            IPv6 PMTU increase, so PMTU increase should be updated here.
2666            Since RFC 1981 doesn't include administrative MTU increase
2667            update PMTU increase is a MUST. (i.e. jumbo frame)
2668          */
2669         /*
2670            If new MTU is less than route PMTU, this new MTU will be the
2671            lowest MTU in the path, update the route PMTU to reflect PMTU
2672            decreases; if new MTU is greater than route PMTU, and the
2673            old MTU is the lowest MTU in the path, update the route PMTU
2674            to reflect the increase. In this case if the other nodes' MTU
2675            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2676            PMTU discouvery.
2677          */
2678         if (rt->dst.dev == arg->dev &&
2679             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2680                 if (rt->rt6i_flags & RTF_CACHE) {
2681                         /* For RTF_CACHE with rt6i_pmtu == 0
2682                          * (i.e. a redirected route),
2683                          * the metrics of its rt->dst.from has already
2684                          * been updated.
2685                          */
2686                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2687                                 rt->rt6i_pmtu = arg->mtu;
2688                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2689                            (dst_mtu(&rt->dst) < arg->mtu &&
2690                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2691                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2692                 }
2693         }
2694         return 0;
2695 }
2696
2697 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2698 {
2699         struct rt6_mtu_change_arg arg = {
2700                 .dev = dev,
2701                 .mtu = mtu,
2702         };
2703
2704         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2705 }
2706
2707 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2708         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2709         [RTA_PREFSRC]           = { .len = sizeof(struct in6_addr) },
2710         [RTA_OIF]               = { .type = NLA_U32 },
2711         [RTA_IIF]               = { .type = NLA_U32 },
2712         [RTA_PRIORITY]          = { .type = NLA_U32 },
2713         [RTA_METRICS]           = { .type = NLA_NESTED },
2714         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2715         [RTA_PREF]              = { .type = NLA_U8 },
2716         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2717         [RTA_ENCAP]             = { .type = NLA_NESTED },
2718         [RTA_UID]               = { .type = NLA_U32 },
2719         [RTA_TABLE]             = { .type = NLA_U32 },
2720 };
2721
2722 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2723                               struct fib6_config *cfg)
2724 {
2725         struct rtmsg *rtm;
2726         struct nlattr *tb[RTA_MAX+1];
2727         unsigned int pref;
2728         int err;
2729
2730         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2731         if (err < 0)
2732                 goto errout;
2733
2734         err = -EINVAL;
2735         rtm = nlmsg_data(nlh);
2736         memset(cfg, 0, sizeof(*cfg));
2737
2738         cfg->fc_table = rtm->rtm_table;
2739         cfg->fc_dst_len = rtm->rtm_dst_len;
2740         cfg->fc_src_len = rtm->rtm_src_len;
2741         cfg->fc_flags = RTF_UP;
2742         cfg->fc_protocol = rtm->rtm_protocol;
2743         cfg->fc_type = rtm->rtm_type;
2744
2745         if (rtm->rtm_type == RTN_UNREACHABLE ||
2746             rtm->rtm_type == RTN_BLACKHOLE ||
2747             rtm->rtm_type == RTN_PROHIBIT ||
2748             rtm->rtm_type == RTN_THROW)
2749                 cfg->fc_flags |= RTF_REJECT;
2750
2751         if (rtm->rtm_type == RTN_LOCAL)
2752                 cfg->fc_flags |= RTF_LOCAL;
2753
2754         if (rtm->rtm_flags & RTM_F_CLONED)
2755                 cfg->fc_flags |= RTF_CACHE;
2756
2757         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2758         cfg->fc_nlinfo.nlh = nlh;
2759         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2760
2761         if (tb[RTA_GATEWAY]) {
2762                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2763                 cfg->fc_flags |= RTF_GATEWAY;
2764         }
2765
2766         if (tb[RTA_DST]) {
2767                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2768
2769                 if (nla_len(tb[RTA_DST]) < plen)
2770                         goto errout;
2771
2772                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2773         }
2774
2775         if (tb[RTA_SRC]) {
2776                 int plen = (rtm->rtm_src_len + 7) >> 3;
2777
2778                 if (nla_len(tb[RTA_SRC]) < plen)
2779                         goto errout;
2780
2781                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2782         }
2783
2784         if (tb[RTA_PREFSRC])
2785                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2786
2787         if (tb[RTA_OIF])
2788                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2789
2790         if (tb[RTA_PRIORITY])
2791                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2792
2793         if (tb[RTA_METRICS]) {
2794                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2795                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2796         }
2797
2798         if (tb[RTA_TABLE])
2799                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2800
2801         if (tb[RTA_MULTIPATH]) {
2802                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2803                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2804         }
2805
2806         if (tb[RTA_PREF]) {
2807                 pref = nla_get_u8(tb[RTA_PREF]);
2808                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2809                     pref != ICMPV6_ROUTER_PREF_HIGH)
2810                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2811                 cfg->fc_flags |= RTF_PREF(pref);
2812         }
2813
2814         if (tb[RTA_ENCAP])
2815                 cfg->fc_encap = tb[RTA_ENCAP];
2816
2817         if (tb[RTA_ENCAP_TYPE])
2818                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2819
2820         err = 0;
2821 errout:
2822         return err;
2823 }
2824
2825 struct rt6_nh {
2826         struct rt6_info *rt6_info;
2827         struct fib6_config r_cfg;
2828         struct mx6_config mxc;
2829         struct list_head next;
2830 };
2831
2832 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2833 {
2834         struct rt6_nh *nh;
2835
2836         list_for_each_entry(nh, rt6_nh_list, next) {
2837                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2838                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2839                         nh->r_cfg.fc_ifindex);
2840         }
2841 }
2842
2843 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2844                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2845 {
2846         struct rt6_nh *nh;
2847         int err = -EEXIST;
2848
2849         list_for_each_entry(nh, rt6_nh_list, next) {
2850                 /* check if rt6_info already exists */
2851                 if (rt6_duplicate_nexthop(nh->rt6_info, rt))
2852                         return err;
2853         }
2854
2855         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2856         if (!nh)
2857                 return -ENOMEM;
2858         nh->rt6_info = rt;
2859         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2860         if (err) {
2861                 kfree(nh);
2862                 return err;
2863         }
2864         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2865         list_add_tail(&nh->next, rt6_nh_list);
2866
2867         return 0;
2868 }
2869
2870 static int ip6_route_multipath_add(struct fib6_config *cfg)
2871 {
2872         struct fib6_config r_cfg;
2873         struct rtnexthop *rtnh;
2874         struct rt6_info *rt;
2875         struct rt6_nh *err_nh;
2876         struct rt6_nh *nh, *nh_safe;
2877         int remaining;
2878         int attrlen;
2879         int err = 1;
2880         int nhn = 0;
2881         int replace = (cfg->fc_nlinfo.nlh &&
2882                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2883         LIST_HEAD(rt6_nh_list);
2884
2885         remaining = cfg->fc_mp_len;
2886         rtnh = (struct rtnexthop *)cfg->fc_mp;
2887
2888         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2889          * rt6_info structs per nexthop
2890          */
2891         while (rtnh_ok(rtnh, remaining)) {
2892                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2893                 if (rtnh->rtnh_ifindex)
2894                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2895
2896                 attrlen = rtnh_attrlen(rtnh);
2897                 if (attrlen > 0) {
2898                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2899
2900                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2901                         if (nla) {
2902                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2903                                 r_cfg.fc_flags |= RTF_GATEWAY;
2904                         }
2905                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2906                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2907                         if (nla)
2908                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2909                 }
2910
2911                 rt = ip6_route_info_create(&r_cfg);
2912                 if (IS_ERR(rt)) {
2913                         err = PTR_ERR(rt);
2914                         rt = NULL;
2915                         goto cleanup;
2916                 }
2917
2918                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2919                 if (err) {
2920                         dst_free(&rt->dst);
2921                         goto cleanup;
2922                 }
2923
2924                 rtnh = rtnh_next(rtnh, &remaining);
2925         }
2926
2927         err_nh = NULL;
2928         list_for_each_entry(nh, &rt6_nh_list, next) {
2929                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2930                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2931                 nh->rt6_info = NULL;
2932                 if (err) {
2933                         if (replace && nhn)
2934                                 ip6_print_replace_route_err(&rt6_nh_list);
2935                         err_nh = nh;
2936                         goto add_errout;
2937                 }
2938
2939                 /* Because each route is added like a single route we remove
2940                  * these flags after the first nexthop: if there is a collision,
2941                  * we have already failed to add the first nexthop:
2942                  * fib6_add_rt2node() has rejected it; when replacing, old
2943                  * nexthops have been replaced by first new, the rest should
2944                  * be added to it.
2945                  */
2946                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2947                                                      NLM_F_REPLACE);
2948                 nhn++;
2949         }
2950
2951         goto cleanup;
2952
2953 add_errout:
2954         /* Delete routes that were already added */
2955         list_for_each_entry(nh, &rt6_nh_list, next) {
2956                 if (err_nh == nh)
2957                         break;
2958                 ip6_route_del(&nh->r_cfg);
2959         }
2960
2961 cleanup:
2962         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2963                 if (nh->rt6_info)
2964                         dst_free(&nh->rt6_info->dst);
2965                 kfree(nh->mxc.mx);
2966                 list_del(&nh->next);
2967                 kfree(nh);
2968         }
2969
2970         return err;
2971 }
2972
2973 static int ip6_route_multipath_del(struct fib6_config *cfg)
2974 {
2975         struct fib6_config r_cfg;
2976         struct rtnexthop *rtnh;
2977         int remaining;
2978         int attrlen;
2979         int err = 1, last_err = 0;
2980
2981         remaining = cfg->fc_mp_len;
2982         rtnh = (struct rtnexthop *)cfg->fc_mp;
2983
2984         /* Parse a Multipath Entry */
2985         while (rtnh_ok(rtnh, remaining)) {
2986                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2987                 if (rtnh->rtnh_ifindex)
2988                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2989
2990                 attrlen = rtnh_attrlen(rtnh);
2991                 if (attrlen > 0) {
2992                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2993
2994                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2995                         if (nla) {
2996                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2997                                 r_cfg.fc_flags |= RTF_GATEWAY;
2998                         }
2999                 }
3000                 err = ip6_route_del(&r_cfg);
3001                 if (err)
3002                         last_err = err;
3003
3004                 rtnh = rtnh_next(rtnh, &remaining);
3005         }
3006
3007         return last_err;
3008 }
3009
3010 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3011 {
3012         struct fib6_config cfg;
3013         int err;
3014
3015         err = rtm_to_fib6_config(skb, nlh, &cfg);
3016         if (err < 0)
3017                 return err;
3018
3019         if (cfg.fc_mp)
3020                 return ip6_route_multipath_del(&cfg);
3021         else
3022                 return ip6_route_del(&cfg);
3023 }
3024
3025 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3026 {
3027         struct fib6_config cfg;
3028         int err;
3029
3030         err = rtm_to_fib6_config(skb, nlh, &cfg);
3031         if (err < 0)
3032                 return err;
3033
3034         if (cfg.fc_mp)
3035                 return ip6_route_multipath_add(&cfg);
3036         else
3037                 return ip6_route_add(&cfg);
3038 }
3039
3040 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3041 {
3042         return NLMSG_ALIGN(sizeof(struct rtmsg))
3043                + nla_total_size(16) /* RTA_SRC */
3044                + nla_total_size(16) /* RTA_DST */
3045                + nla_total_size(16) /* RTA_GATEWAY */
3046                + nla_total_size(16) /* RTA_PREFSRC */
3047                + nla_total_size(4) /* RTA_TABLE */
3048                + nla_total_size(4) /* RTA_IIF */
3049                + nla_total_size(4) /* RTA_OIF */
3050                + nla_total_size(4) /* RTA_PRIORITY */
3051                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3052                + nla_total_size(sizeof(struct rta_cacheinfo))
3053                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3054                + nla_total_size(1) /* RTA_PREF */
3055                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3056 }
3057
3058 static int rt6_fill_node(struct net *net,
3059                          struct sk_buff *skb, struct rt6_info *rt,
3060                          struct in6_addr *dst, struct in6_addr *src,
3061                          int iif, int type, u32 portid, u32 seq,
3062                          int prefix, int nowait, unsigned int flags)
3063 {
3064         u32 metrics[RTAX_MAX];
3065         struct rtmsg *rtm;
3066         struct nlmsghdr *nlh;
3067         long expires;
3068         u32 table;
3069
3070         if (prefix) {   /* user wants prefix routes only */
3071                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3072                         /* success since this is not a prefix route */
3073                         return 1;
3074                 }
3075         }
3076
3077         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3078         if (!nlh)
3079                 return -EMSGSIZE;
3080
3081         rtm = nlmsg_data(nlh);
3082         rtm->rtm_family = AF_INET6;
3083         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3084         rtm->rtm_src_len = rt->rt6i_src.plen;
3085         rtm->rtm_tos = 0;
3086         if (rt->rt6i_table)
3087                 table = rt->rt6i_table->tb6_id;
3088         else
3089                 table = RT6_TABLE_UNSPEC;
3090         rtm->rtm_table = table;
3091         if (nla_put_u32(skb, RTA_TABLE, table))
3092                 goto nla_put_failure;
3093         if (rt->rt6i_flags & RTF_REJECT) {
3094                 switch (rt->dst.error) {
3095                 case -EINVAL:
3096                         rtm->rtm_type = RTN_BLACKHOLE;
3097                         break;
3098                 case -EACCES:
3099                         rtm->rtm_type = RTN_PROHIBIT;
3100                         break;
3101                 case -EAGAIN:
3102                         rtm->rtm_type = RTN_THROW;
3103                         break;
3104                 default:
3105                         rtm->rtm_type = RTN_UNREACHABLE;
3106                         break;
3107                 }
3108         }
3109         else if (rt->rt6i_flags & RTF_LOCAL)
3110                 rtm->rtm_type = RTN_LOCAL;
3111         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3112                 rtm->rtm_type = RTN_LOCAL;
3113         else
3114                 rtm->rtm_type = RTN_UNICAST;
3115         rtm->rtm_flags = 0;
3116         if (!netif_carrier_ok(rt->dst.dev)) {
3117                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3118                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3119                         rtm->rtm_flags |= RTNH_F_DEAD;
3120         }
3121         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3122         rtm->rtm_protocol = rt->rt6i_protocol;
3123         if (rt->rt6i_flags & RTF_DYNAMIC)
3124                 rtm->rtm_protocol = RTPROT_REDIRECT;
3125         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3126                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3127                         rtm->rtm_protocol = RTPROT_RA;
3128                 else
3129                         rtm->rtm_protocol = RTPROT_KERNEL;
3130         }
3131
3132         if (rt->rt6i_flags & RTF_CACHE)
3133                 rtm->rtm_flags |= RTM_F_CLONED;
3134
3135         if (dst) {
3136                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3137                         goto nla_put_failure;
3138                 rtm->rtm_dst_len = 128;
3139         } else if (rtm->rtm_dst_len)
3140                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3141                         goto nla_put_failure;
3142 #ifdef CONFIG_IPV6_SUBTREES
3143         if (src) {
3144                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3145                         goto nla_put_failure;
3146                 rtm->rtm_src_len = 128;
3147         } else if (rtm->rtm_src_len &&
3148                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3149                 goto nla_put_failure;
3150 #endif
3151         if (iif) {
3152 #ifdef CONFIG_IPV6_MROUTE
3153                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3154                         int err = ip6mr_get_route(net, skb, rtm, nowait,
3155                                                   portid);
3156
3157                         if (err <= 0) {
3158                                 if (!nowait) {
3159                                         if (err == 0)
3160                                                 return 0;
3161                                         goto nla_put_failure;
3162                                 } else {
3163                                         if (err == -EMSGSIZE)
3164                                                 goto nla_put_failure;
3165                                 }
3166                         }
3167                 } else
3168 #endif
3169                         if (nla_put_u32(skb, RTA_IIF, iif))
3170                                 goto nla_put_failure;
3171         } else if (dst) {
3172                 struct in6_addr saddr_buf;
3173                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3174                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3175                         goto nla_put_failure;
3176         }
3177
3178         if (rt->rt6i_prefsrc.plen) {
3179                 struct in6_addr saddr_buf;
3180                 saddr_buf = rt->rt6i_prefsrc.addr;
3181                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3182                         goto nla_put_failure;
3183         }
3184
3185         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3186         if (rt->rt6i_pmtu)
3187                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3188         if (rtnetlink_put_metrics(skb, metrics) < 0)
3189                 goto nla_put_failure;
3190
3191         if (rt->rt6i_flags & RTF_GATEWAY) {
3192                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3193                         goto nla_put_failure;
3194         }
3195
3196         if (rt->dst.dev &&
3197             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3198                 goto nla_put_failure;
3199         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3200                 goto nla_put_failure;
3201
3202         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3203
3204         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3205                 goto nla_put_failure;
3206
3207         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3208                 goto nla_put_failure;
3209
3210         if (lwtunnel_fill_encap(skb, rt->dst.lwtstate) < 0)
3211                 goto nla_put_failure;
3212
3213         nlmsg_end(skb, nlh);
3214         return 0;
3215
3216 nla_put_failure:
3217         nlmsg_cancel(skb, nlh);
3218         return -EMSGSIZE;
3219 }
3220
3221 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3222 {
3223         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3224         int prefix;
3225
3226         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3227                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3228                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3229         } else
3230                 prefix = 0;
3231
3232         return rt6_fill_node(arg->net,
3233                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3234                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3235                      prefix, 0, NLM_F_MULTI);
3236 }
3237
3238 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3239 {
3240         struct net *net = sock_net(in_skb->sk);
3241         struct nlattr *tb[RTA_MAX+1];
3242         struct rt6_info *rt;
3243         struct sk_buff *skb;
3244         struct rtmsg *rtm;
3245         struct flowi6 fl6;
3246         int err, iif = 0, oif = 0;
3247
3248         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3249         if (err < 0)
3250                 goto errout;
3251
3252         err = -EINVAL;
3253         memset(&fl6, 0, sizeof(fl6));
3254
3255         if (tb[RTA_SRC]) {
3256                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3257                         goto errout;
3258
3259                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3260         }
3261
3262         if (tb[RTA_DST]) {
3263                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3264                         goto errout;
3265
3266                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3267         }
3268
3269         if (tb[RTA_IIF])
3270                 iif = nla_get_u32(tb[RTA_IIF]);
3271
3272         if (tb[RTA_OIF])
3273                 oif = nla_get_u32(tb[RTA_OIF]);
3274
3275         if (tb[RTA_MARK])
3276                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3277
3278         if (tb[RTA_UID])
3279                 fl6.flowi6_uid = make_kuid(current_user_ns(),
3280                                            nla_get_u32(tb[RTA_UID]));
3281         else
3282                 fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
3283
3284         if (iif) {
3285                 struct net_device *dev;
3286                 int flags = 0;
3287
3288                 dev = __dev_get_by_index(net, iif);
3289                 if (!dev) {
3290                         err = -ENODEV;
3291                         goto errout;
3292                 }
3293
3294                 fl6.flowi6_iif = iif;
3295
3296                 if (!ipv6_addr_any(&fl6.saddr))
3297                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3298
3299                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3300                                                                flags);
3301         } else {
3302                 fl6.flowi6_oif = oif;
3303
3304                 if (netif_index_is_l3_master(net, oif)) {
3305                         fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
3306                                            FLOWI_FLAG_SKIP_NH_OIF;
3307                 }
3308
3309                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3310         }
3311
3312         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3313         if (!skb) {
3314                 ip6_rt_put(rt);
3315                 err = -ENOBUFS;
3316                 goto errout;
3317         }
3318
3319         /* Reserve room for dummy headers, this skb can pass
3320            through good chunk of routing engine.
3321          */
3322         skb_reset_mac_header(skb);
3323         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3324
3325         skb_dst_set(skb, &rt->dst);
3326
3327         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3328                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3329                             nlh->nlmsg_seq, 0, 0, 0);
3330         if (err < 0) {
3331                 kfree_skb(skb);
3332                 goto errout;
3333         }
3334
3335         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3336 errout:
3337         return err;
3338 }
3339
3340 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
3341                      unsigned int nlm_flags)
3342 {
3343         struct sk_buff *skb;
3344         struct net *net = info->nl_net;
3345         u32 seq;
3346         int err;
3347
3348         err = -ENOBUFS;
3349         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3350
3351         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3352         if (!skb)
3353                 goto errout;
3354
3355         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3356                                 event, info->portid, seq, 0, 0, nlm_flags);
3357         if (err < 0) {
3358                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3359                 WARN_ON(err == -EMSGSIZE);
3360                 kfree_skb(skb);
3361                 goto errout;
3362         }
3363         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3364                     info->nlh, gfp_any());
3365         return;
3366 errout:
3367         if (err < 0)
3368                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3369 }
3370
3371 static int ip6_route_dev_notify(struct notifier_block *this,
3372                                 unsigned long event, void *ptr)
3373 {
3374         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3375         struct net *net = dev_net(dev);
3376
3377         if (!(dev->flags & IFF_LOOPBACK))
3378                 return NOTIFY_OK;
3379
3380         if (event == NETDEV_REGISTER) {
3381                 net->ipv6.ip6_null_entry->dst.dev = dev;
3382                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3383 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3384                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3385                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3386                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3387                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3388 #endif
3389          } else if (event == NETDEV_UNREGISTER &&
3390                     dev->reg_state != NETREG_UNREGISTERED) {
3391                 /* NETDEV_UNREGISTER could be fired for multiple times by
3392                  * netdev_wait_allrefs(). Make sure we only call this once.
3393                  */
3394                 in6_dev_put(net->ipv6.ip6_null_entry->rt6i_idev);
3395 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3396                 in6_dev_put(net->ipv6.ip6_prohibit_entry->rt6i_idev);
3397                 in6_dev_put(net->ipv6.ip6_blk_hole_entry->rt6i_idev);
3398 #endif
3399         }
3400
3401         return NOTIFY_OK;
3402 }
3403
3404 /*
3405  *      /proc
3406  */
3407
3408 #ifdef CONFIG_PROC_FS
3409
3410 static const struct file_operations ipv6_route_proc_fops = {
3411         .owner          = THIS_MODULE,
3412         .open           = ipv6_route_open,
3413         .read           = seq_read,
3414         .llseek         = seq_lseek,
3415         .release        = seq_release_net,
3416 };
3417
3418 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3419 {
3420         struct net *net = (struct net *)seq->private;
3421         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3422                    net->ipv6.rt6_stats->fib_nodes,
3423                    net->ipv6.rt6_stats->fib_route_nodes,
3424                    net->ipv6.rt6_stats->fib_rt_alloc,
3425                    net->ipv6.rt6_stats->fib_rt_entries,
3426                    net->ipv6.rt6_stats->fib_rt_cache,
3427                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3428                    net->ipv6.rt6_stats->fib_discarded_routes);
3429
3430         return 0;
3431 }
3432
3433 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3434 {
3435         return single_open_net(inode, file, rt6_stats_seq_show);
3436 }
3437
3438 static const struct file_operations rt6_stats_seq_fops = {
3439         .owner   = THIS_MODULE,
3440         .open    = rt6_stats_seq_open,
3441         .read    = seq_read,
3442         .llseek  = seq_lseek,
3443         .release = single_release_net,
3444 };
3445 #endif  /* CONFIG_PROC_FS */
3446
3447 #ifdef CONFIG_SYSCTL
3448
3449 static
3450 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3451                               void __user *buffer, size_t *lenp, loff_t *ppos)
3452 {
3453         struct net *net;
3454         int delay;
3455         if (!write)
3456                 return -EINVAL;
3457
3458         net = (struct net *)ctl->extra1;
3459         delay = net->ipv6.sysctl.flush_delay;
3460         proc_dointvec(ctl, write, buffer, lenp, ppos);
3461         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3462         return 0;
3463 }
3464
3465 struct ctl_table ipv6_route_table_template[] = {
3466         {
3467                 .procname       =       "flush",
3468                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3469                 .maxlen         =       sizeof(int),
3470                 .mode           =       0200,
3471                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3472         },
3473         {
3474                 .procname       =       "gc_thresh",
3475                 .data           =       &ip6_dst_ops_template.gc_thresh,
3476                 .maxlen         =       sizeof(int),
3477                 .mode           =       0644,
3478                 .proc_handler   =       proc_dointvec,
3479         },
3480         {
3481                 .procname       =       "max_size",
3482                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3483                 .maxlen         =       sizeof(int),
3484                 .mode           =       0644,
3485                 .proc_handler   =       proc_dointvec,
3486         },
3487         {
3488                 .procname       =       "gc_min_interval",
3489                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3490                 .maxlen         =       sizeof(int),
3491                 .mode           =       0644,
3492                 .proc_handler   =       proc_dointvec_jiffies,
3493         },
3494         {
3495                 .procname       =       "gc_timeout",
3496                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3497                 .maxlen         =       sizeof(int),
3498                 .mode           =       0644,
3499                 .proc_handler   =       proc_dointvec_jiffies,
3500         },
3501         {
3502                 .procname       =       "gc_interval",
3503                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3504                 .maxlen         =       sizeof(int),
3505                 .mode           =       0644,
3506                 .proc_handler   =       proc_dointvec_jiffies,
3507         },
3508         {
3509                 .procname       =       "gc_elasticity",
3510                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3511                 .maxlen         =       sizeof(int),
3512                 .mode           =       0644,
3513                 .proc_handler   =       proc_dointvec,
3514         },
3515         {
3516                 .procname       =       "mtu_expires",
3517                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3518                 .maxlen         =       sizeof(int),
3519                 .mode           =       0644,
3520                 .proc_handler   =       proc_dointvec_jiffies,
3521         },
3522         {
3523                 .procname       =       "min_adv_mss",
3524                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3525                 .maxlen         =       sizeof(int),
3526                 .mode           =       0644,
3527                 .proc_handler   =       proc_dointvec,
3528         },
3529         {
3530                 .procname       =       "gc_min_interval_ms",
3531                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3532                 .maxlen         =       sizeof(int),
3533                 .mode           =       0644,
3534                 .proc_handler   =       proc_dointvec_ms_jiffies,
3535         },
3536         { }
3537 };
3538
3539 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3540 {
3541         struct ctl_table *table;
3542
3543         table = kmemdup(ipv6_route_table_template,
3544                         sizeof(ipv6_route_table_template),
3545                         GFP_KERNEL);
3546
3547         if (table) {
3548                 table[0].data = &net->ipv6.sysctl.flush_delay;
3549                 table[0].extra1 = net;
3550                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3551                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3552                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3553                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3554                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3555                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3556                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3557                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3558                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3559
3560                 /* Don't export sysctls to unprivileged users */
3561                 if (net->user_ns != &init_user_ns)
3562                         table[0].procname = NULL;
3563         }
3564
3565         return table;
3566 }
3567 #endif
3568
3569 static int __net_init ip6_route_net_init(struct net *net)
3570 {
3571         int ret = -ENOMEM;
3572
3573         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3574                sizeof(net->ipv6.ip6_dst_ops));
3575
3576         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3577                 goto out_ip6_dst_ops;
3578
3579         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3580                                            sizeof(*net->ipv6.ip6_null_entry),
3581                                            GFP_KERNEL);
3582         if (!net->ipv6.ip6_null_entry)
3583                 goto out_ip6_dst_entries;
3584         net->ipv6.ip6_null_entry->dst.path =
3585                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3586         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3587         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3588                          ip6_template_metrics, true);
3589
3590 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3591         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3592                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3593                                                GFP_KERNEL);
3594         if (!net->ipv6.ip6_prohibit_entry)
3595                 goto out_ip6_null_entry;
3596         net->ipv6.ip6_prohibit_entry->dst.path =
3597                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3598         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3599         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3600                          ip6_template_metrics, true);
3601
3602         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3603                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3604                                                GFP_KERNEL);
3605         if (!net->ipv6.ip6_blk_hole_entry)
3606                 goto out_ip6_prohibit_entry;
3607         net->ipv6.ip6_blk_hole_entry->dst.path =
3608                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3609         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3610         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3611                          ip6_template_metrics, true);
3612 #endif
3613
3614         net->ipv6.sysctl.flush_delay = 0;
3615         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3616         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3617         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3618         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3619         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3620         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3621         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3622
3623         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3624
3625         ret = 0;
3626 out:
3627         return ret;
3628
3629 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3630 out_ip6_prohibit_entry:
3631         kfree(net->ipv6.ip6_prohibit_entry);
3632 out_ip6_null_entry:
3633         kfree(net->ipv6.ip6_null_entry);
3634 #endif
3635 out_ip6_dst_entries:
3636         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3637 out_ip6_dst_ops:
3638         goto out;
3639 }
3640
3641 static void __net_exit ip6_route_net_exit(struct net *net)
3642 {
3643         kfree(net->ipv6.ip6_null_entry);
3644 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3645         kfree(net->ipv6.ip6_prohibit_entry);
3646         kfree(net->ipv6.ip6_blk_hole_entry);
3647 #endif
3648         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3649 }
3650
3651 static int __net_init ip6_route_net_init_late(struct net *net)
3652 {
3653 #ifdef CONFIG_PROC_FS
3654         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3655         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3656 #endif
3657         return 0;
3658 }
3659
3660 static void __net_exit ip6_route_net_exit_late(struct net *net)
3661 {
3662 #ifdef CONFIG_PROC_FS
3663         remove_proc_entry("ipv6_route", net->proc_net);
3664         remove_proc_entry("rt6_stats", net->proc_net);
3665 #endif
3666 }
3667
3668 static struct pernet_operations ip6_route_net_ops = {
3669         .init = ip6_route_net_init,
3670         .exit = ip6_route_net_exit,
3671 };
3672
3673 static int __net_init ipv6_inetpeer_init(struct net *net)
3674 {
3675         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3676
3677         if (!bp)
3678                 return -ENOMEM;
3679         inet_peer_base_init(bp);
3680         net->ipv6.peers = bp;
3681         return 0;
3682 }
3683
3684 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3685 {
3686         struct inet_peer_base *bp = net->ipv6.peers;
3687
3688         net->ipv6.peers = NULL;
3689         inetpeer_invalidate_tree(bp);
3690         kfree(bp);
3691 }
3692
3693 static struct pernet_operations ipv6_inetpeer_ops = {
3694         .init   =       ipv6_inetpeer_init,
3695         .exit   =       ipv6_inetpeer_exit,
3696 };
3697
3698 static struct pernet_operations ip6_route_net_late_ops = {
3699         .init = ip6_route_net_init_late,
3700         .exit = ip6_route_net_exit_late,
3701 };
3702
3703 static struct notifier_block ip6_route_dev_notifier = {
3704         .notifier_call = ip6_route_dev_notify,
3705         .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
3706 };
3707
3708 void __init ip6_route_init_special_entries(void)
3709 {
3710         /* Registering of the loopback is done before this portion of code,
3711          * the loopback reference in rt6_info will not be taken, do it
3712          * manually for init_net */
3713         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3714         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3715   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3716         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3717         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3718         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3719         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3720   #endif
3721 }
3722
3723 int __init ip6_route_init(void)
3724 {
3725         int ret;
3726         int cpu;
3727
3728         ret = -ENOMEM;
3729         ip6_dst_ops_template.kmem_cachep =
3730                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3731                                   SLAB_HWCACHE_ALIGN, NULL);
3732         if (!ip6_dst_ops_template.kmem_cachep)
3733                 goto out;
3734
3735         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3736         if (ret)
3737                 goto out_kmem_cache;
3738
3739         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3740         if (ret)
3741                 goto out_dst_entries;
3742
3743         ret = register_pernet_subsys(&ip6_route_net_ops);
3744         if (ret)
3745                 goto out_register_inetpeer;
3746
3747         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3748
3749         ret = fib6_init();
3750         if (ret)
3751                 goto out_register_subsys;
3752
3753         ret = xfrm6_init();
3754         if (ret)
3755                 goto out_fib6_init;
3756
3757         ret = fib6_rules_init();
3758         if (ret)
3759                 goto xfrm6_init;
3760
3761         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3762         if (ret)
3763                 goto fib6_rules_init;
3764
3765         ret = -ENOBUFS;
3766         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3767             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3768             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3769                 goto out_register_late_subsys;
3770
3771         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3772         if (ret)
3773                 goto out_register_late_subsys;
3774
3775         for_each_possible_cpu(cpu) {
3776                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3777
3778                 INIT_LIST_HEAD(&ul->head);
3779                 spin_lock_init(&ul->lock);
3780         }
3781
3782 out:
3783         return ret;
3784
3785 out_register_late_subsys:
3786         unregister_pernet_subsys(&ip6_route_net_late_ops);
3787 fib6_rules_init:
3788         fib6_rules_cleanup();
3789 xfrm6_init:
3790         xfrm6_fini();
3791 out_fib6_init:
3792         fib6_gc_cleanup();
3793 out_register_subsys:
3794         unregister_pernet_subsys(&ip6_route_net_ops);
3795 out_register_inetpeer:
3796         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3797 out_dst_entries:
3798         dst_entries_destroy(&ip6_dst_blackhole_ops);
3799 out_kmem_cache:
3800         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3801         goto out;
3802 }
3803
3804 void ip6_route_cleanup(void)
3805 {
3806         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3807         unregister_pernet_subsys(&ip6_route_net_late_ops);
3808         fib6_rules_cleanup();
3809         xfrm6_fini();
3810         fib6_gc_cleanup();
3811         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3812         unregister_pernet_subsys(&ip6_route_net_ops);
3813         dst_entries_destroy(&ip6_dst_blackhole_ops);
3814         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3815 }