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  *      $Id: route.c,v 1.56 2001/10/31 21:55:55 davem Exp $
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 /*      Changes:
  17  *
  18  *      YOSHIFUJI Hideaki @USAGI
  19  *              reworked default router selection.
  20  *              - respect outgoing interface
  21  *              - select from (probably) reachable routers (i.e.
  22  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  23  *              - always select the same router if it is (probably)
  24  *              reachable.  otherwise, round-robin the list.
  25  *      Ville Nuorvala
  26  *              Fixed routing subtrees.
  27  */
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/types.h>
  32 #include <linux/times.h>
  33 #include <linux/socket.h>
  34 #include <linux/sockios.h>
  35 #include <linux/net.h>
  36 #include <linux/route.h>
  37 #include <linux/netdevice.h>
  38 #include <linux/in6.h>
  39 #include <linux/init.h>
  40 #include <linux/if_arp.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/seq_file.h>
  43 #include <net/net_namespace.h>
  44 #include <net/snmp.h>
  45 #include <net/ipv6.h>
  46 #include <net/ip6_fib.h>
  47 #include <net/ip6_route.h>
  48 #include <net/ndisc.h>
  49 #include <net/addrconf.h>
  50 #include <net/tcp.h>
  51 #include <linux/rtnetlink.h>
  52 #include <net/dst.h>
  53 #include <net/xfrm.h>
  54 #include <net/netevent.h>
  55 #include <net/netlink.h>
  56
  57 #include <asm/uaccess.h>
  58
  59 #ifdef CONFIG_SYSCTL
  60 #include <linux/sysctl.h>
  61 #endif
  62
  63 /* Set to 3 to get tracing. */
  64 #define RT6_DEBUG 2
  65
  66 #if RT6_DEBUG >= 3
  67 #define RDBG(x) printk x
  68 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
  69 #else
  70 #define RDBG(x)
  71 #define RT6_TRACE(x...) do { ; } while (0)
  72 #endif
  73
  74 #define CLONE_OFFLINK_ROUTE 0
  75
  76 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
  77 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  78 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  79 static void             ip6_dst_destroy(struct dst_entry *);
  80 static void             ip6_dst_ifdown(struct dst_entry *,
  81                                        struct net_device *dev, int how);
  82 static int               ip6_dst_gc(struct dst_ops *ops);
  83
  84 static int              ip6_pkt_discard(struct sk_buff *skb);
  85 static int              ip6_pkt_discard_out(struct sk_buff *skb);
  86 static void             ip6_link_failure(struct sk_buff *skb);
  87 static void             ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
  88
  89 #ifdef CONFIG_IPV6_ROUTE_INFO
  90 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
  91                                            struct in6_addr *gwaddr, int ifindex,
  92                                            unsigned pref);
  93 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
  94                                            struct in6_addr *gwaddr, int ifindex);
  95 #endif
  96
  97 static struct dst_ops ip6_dst_ops = {
  98         .family                 =       AF_INET6,
  99         .protocol               =       __constant_htons(ETH_P_IPV6),
 100         .gc                     =       ip6_dst_gc,
 101         .gc_thresh              =       1024,
 102         .check                  =       ip6_dst_check,
 103         .destroy                =       ip6_dst_destroy,
 104         .ifdown                 =       ip6_dst_ifdown,
 105         .negative_advice        =       ip6_negative_advice,
 106         .link_failure           =       ip6_link_failure,
 107         .update_pmtu            =       ip6_rt_update_pmtu,
 108         .local_out              =       ip6_local_out,
 109         .entry_size             =       sizeof(struct rt6_info),
 110         .entries                =       ATOMIC_INIT(0),
 111 };
 112
 113 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
 114 {
 115 }
 116
 117 static struct dst_ops ip6_dst_blackhole_ops = {
 118         .family                 =       AF_INET6,
 119         .protocol               =       __constant_htons(ETH_P_IPV6),
 120         .destroy                =       ip6_dst_destroy,
 121         .check                  =       ip6_dst_check,
 122         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 123         .entry_size             =       sizeof(struct rt6_info),
 124         .entries                =       ATOMIC_INIT(0),
 125 };
 126
 127 struct rt6_info ip6_null_entry = {
 128         .u = {
 129                 .dst = {
 130                         .__refcnt       = ATOMIC_INIT(1),
 131                         .__use          = 1,
 132                         .obsolete       = -1,
 133                         .error          = -ENETUNREACH,
 134                         .metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
 135                         .input          = ip6_pkt_discard,
 136                         .output         = ip6_pkt_discard_out,
 137                         .ops            = &ip6_dst_ops,
 138                         .path           = (struct dst_entry*)&ip6_null_entry,
 139                 }
 140         },
 141         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 142         .rt6i_metric    = ~(u32) 0,
 143         .rt6i_ref       = ATOMIC_INIT(1),
 144 };
 145
 146 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 147
 148 static int ip6_pkt_prohibit(struct sk_buff *skb);
 149 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
 150
 151 struct rt6_info ip6_prohibit_entry = {
 152         .u = {
 153                 .dst = {
 154                         .__refcnt       = ATOMIC_INIT(1),
 155                         .__use          = 1,
 156                         .obsolete       = -1,
 157                         .error          = -EACCES,
 158                         .metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
 159                         .input          = ip6_pkt_prohibit,
 160                         .output         = ip6_pkt_prohibit_out,
 161                         .ops            = &ip6_dst_ops,
 162                         .path           = (struct dst_entry*)&ip6_prohibit_entry,
 163                 }
 164         },
 165         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 166         .rt6i_metric    = ~(u32) 0,
 167         .rt6i_ref       = ATOMIC_INIT(1),
 168 };
 169
 170 struct rt6_info ip6_blk_hole_entry = {
 171         .u = {
 172                 .dst = {
 173                         .__refcnt       = ATOMIC_INIT(1),
 174                         .__use          = 1,
 175                         .obsolete       = -1,
 176                         .error          = -EINVAL,
 177                         .metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
 178                         .input          = dst_discard,
 179                         .output         = dst_discard,
 180                         .ops            = &ip6_dst_ops,
 181                         .path           = (struct dst_entry*)&ip6_blk_hole_entry,
 182                 }
 183         },
 184         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 185         .rt6i_metric    = ~(u32) 0,
 186         .rt6i_ref       = ATOMIC_INIT(1),
 187 };
 188
 189 #endif
 190
 191 /* allocate dst with ip6_dst_ops */
 192 static __inline__ struct rt6_info *ip6_dst_alloc(void)
 193 {
 194         return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
 195 }
 196
 197 static void ip6_dst_destroy(struct dst_entry *dst)
 198 {
 199         struct rt6_info *rt = (struct rt6_info *)dst;
 200         struct inet6_dev *idev = rt->rt6i_idev;
 201
 202         if (idev != NULL) {
 203                 rt->rt6i_idev = NULL;
 204                 in6_dev_put(idev);
 205         }
 206 }
 207
 208 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 209                            int how)
 210 {
 211         struct rt6_info *rt = (struct rt6_info *)dst;
 212         struct inet6_dev *idev = rt->rt6i_idev;
 213         struct net_device *loopback_dev =
 214                 dev->nd_net->loopback_dev;
 215
 216         if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
 217                 struct inet6_dev *loopback_idev =
 218                         in6_dev_get(loopback_dev);
 219                 if (loopback_idev != NULL) {
 220                         rt->rt6i_idev = loopback_idev;
 221                         in6_dev_put(idev);
 222                 }
 223         }
 224 }
 225
 226 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
 227 {
 228         return (rt->rt6i_flags & RTF_EXPIRES &&
 229                 time_after(jiffies, rt->rt6i_expires));
 230 }
 231
 232 static inline int rt6_need_strict(struct in6_addr *daddr)
 233 {
 234         return (ipv6_addr_type(daddr) &
 235                 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
 236 }
 237
 238 /*
 239  *      Route lookup. Any table->tb6_lock is implied.
 240  */
 241
 242 static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
 243                                                     int oif,
 244                                                     int strict)
 245 {
 246         struct rt6_info *local = NULL;
 247         struct rt6_info *sprt;
 248
 249         if (oif) {
 250                 for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
 251                         struct net_device *dev = sprt->rt6i_dev;
 252                         if (dev->ifindex == oif)
 253                                 return sprt;
 254                         if (dev->flags & IFF_LOOPBACK) {
 255                                 if (sprt->rt6i_idev == NULL ||
 256                                     sprt->rt6i_idev->dev->ifindex != oif) {
 257                                         if (strict && oif)
 258                                                 continue;
 259                                         if (local && (!oif ||
 260                                                       local->rt6i_idev->dev->ifindex == oif))
 261                                                 continue;
 262                                 }
 263                                 local = sprt;
 264                         }
 265                 }
 266
 267                 if (local)
 268                         return local;
 269
 270                 if (strict)
 271                         return &ip6_null_entry;
 272         }
 273         return rt;
 274 }
 275
 276 #ifdef CONFIG_IPV6_ROUTER_PREF
 277 static void rt6_probe(struct rt6_info *rt)
 278 {
 279         struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
 280         /*
 281          * Okay, this does not seem to be appropriate
 282          * for now, however, we need to check if it
 283          * is really so; aka Router Reachability Probing.
 284          *
 285          * Router Reachability Probe MUST be rate-limited
 286          * to no more than one per minute.
 287          */
 288         if (!neigh || (neigh->nud_state & NUD_VALID))
 289                 return;
 290         read_lock_bh(&neigh->lock);
 291         if (!(neigh->nud_state & NUD_VALID) &&
 292             time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
 293                 struct in6_addr mcaddr;
 294                 struct in6_addr *target;
 295
 296                 neigh->updated = jiffies;
 297                 read_unlock_bh(&neigh->lock);
 298
 299                 target = (struct in6_addr *)&neigh->primary_key;
 300                 addrconf_addr_solict_mult(target, &mcaddr);
 301                 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
 302         } else
 303                 read_unlock_bh(&neigh->lock);
 304 }
 305 #else
 306 static inline void rt6_probe(struct rt6_info *rt)
 307 {
 308         return;
 309 }
 310 #endif
 311
 312 /*
 313  * Default Router Selection (RFC 2461 6.3.6)
 314  */
 315 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 316 {
 317         struct net_device *dev = rt->rt6i_dev;
 318         if (!oif || dev->ifindex == oif)
 319                 return 2;
 320         if ((dev->flags & IFF_LOOPBACK) &&
 321             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 322                 return 1;
 323         return 0;
 324 }
 325
 326 static inline int rt6_check_neigh(struct rt6_info *rt)
 327 {
 328         struct neighbour *neigh = rt->rt6i_nexthop;
 329         int m;
 330         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 331             !(rt->rt6i_flags & RTF_GATEWAY))
 332                 m = 1;
 333         else if (neigh) {
 334                 read_lock_bh(&neigh->lock);
 335                 if (neigh->nud_state & NUD_VALID)
 336                         m = 2;
 337 #ifdef CONFIG_IPV6_ROUTER_PREF
 338                 else if (neigh->nud_state & NUD_FAILED)
 339                         m = 0;
 340 #endif
 341                 else
 342                         m = 1;
 343                 read_unlock_bh(&neigh->lock);
 344         } else
 345                 m = 0;
 346         return m;
 347 }
 348
 349 static int rt6_score_route(struct rt6_info *rt, int oif,
 350                            int strict)
 351 {
 352         int m, n;
 353
 354         m = rt6_check_dev(rt, oif);
 355         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 356                 return -1;
 357 #ifdef CONFIG_IPV6_ROUTER_PREF
 358         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 359 #endif
 360         n = rt6_check_neigh(rt);
 361         if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
 362                 return -1;
 363         return m;
 364 }
 365
 366 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 367                                    int *mpri, struct rt6_info *match)
 368 {
 369         int m;
 370
 371         if (rt6_check_expired(rt))
 372                 goto out;
 373
 374         m = rt6_score_route(rt, oif, strict);
 375         if (m < 0)
 376                 goto out;
 377
 378         if (m > *mpri) {
 379                 if (strict & RT6_LOOKUP_F_REACHABLE)
 380                         rt6_probe(match);
 381                 *mpri = m;
 382                 match = rt;
 383         } else if (strict & RT6_LOOKUP_F_REACHABLE) {
 384                 rt6_probe(rt);
 385         }
 386
 387 out:
 388         return match;
 389 }
 390
 391 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 392                                      struct rt6_info *rr_head,
 393                                      u32 metric, int oif, int strict)
 394 {
 395         struct rt6_info *rt, *match;
 396         int mpri = -1;
 397
 398         match = NULL;
 399         for (rt = rr_head; rt && rt->rt6i_metric == metric;
 400              rt = rt->u.dst.rt6_next)
 401                 match = find_match(rt, oif, strict, &mpri, match);
 402         for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
 403              rt = rt->u.dst.rt6_next)
 404                 match = find_match(rt, oif, strict, &mpri, match);
 405
 406         return match;
 407 }
 408
 409 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 410 {
 411         struct rt6_info *match, *rt0;
 412
 413         RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
 414                   __FUNCTION__, fn->leaf, oif);
 415
 416         rt0 = fn->rr_ptr;
 417         if (!rt0)
 418                 fn->rr_ptr = rt0 = fn->leaf;
 419
 420         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
 421
 422         if (!match &&
 423             (strict & RT6_LOOKUP_F_REACHABLE)) {
 424                 struct rt6_info *next = rt0->u.dst.rt6_next;
 425
 426                 /* no entries matched; do round-robin */
 427                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 428                         next = fn->leaf;
 429
 430                 if (next != rt0)
 431                         fn->rr_ptr = next;
 432         }
 433
 434         RT6_TRACE("%s() => %p\n",
 435                   __FUNCTION__, match);
 436
 437         return (match ? match : &ip6_null_entry);
 438 }
 439
 440 #ifdef CONFIG_IPV6_ROUTE_INFO
 441 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 442                   struct in6_addr *gwaddr)
 443 {
 444         struct route_info *rinfo = (struct route_info *) opt;
 445         struct in6_addr prefix_buf, *prefix;
 446         unsigned int pref;
 447         u32 lifetime;
 448         struct rt6_info *rt;
 449
 450         if (len < sizeof(struct route_info)) {
 451                 return -EINVAL;
 452         }
 453
 454         /* Sanity check for prefix_len and length */
 455         if (rinfo->length > 3) {
 456                 return -EINVAL;
 457         } else if (rinfo->prefix_len > 128) {
 458                 return -EINVAL;
 459         } else if (rinfo->prefix_len > 64) {
 460                 if (rinfo->length < 2) {
 461                         return -EINVAL;
 462                 }
 463         } else if (rinfo->prefix_len > 0) {
 464                 if (rinfo->length < 1) {
 465                         return -EINVAL;
 466                 }
 467         }
 468
 469         pref = rinfo->route_pref;
 470         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 471                 pref = ICMPV6_ROUTER_PREF_MEDIUM;
 472
 473         lifetime = ntohl(rinfo->lifetime);
 474         if (lifetime == 0xffffffff) {
 475                 /* infinity */
 476         } else if (lifetime > 0x7fffffff/HZ) {
 477                 /* Avoid arithmetic overflow */
 478                 lifetime = 0x7fffffff/HZ - 1;
 479         }
 480
 481         if (rinfo->length == 3)
 482                 prefix = (struct in6_addr *)rinfo->prefix;
 483         else {
 484                 /* this function is safe */
 485                 ipv6_addr_prefix(&prefix_buf,
 486                                  (struct in6_addr *)rinfo->prefix,
 487                                  rinfo->prefix_len);
 488                 prefix = &prefix_buf;
 489         }
 490
 491         rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
 492
 493         if (rt && !lifetime) {
 494                 ip6_del_rt(rt);
 495                 rt = NULL;
 496         }
 497
 498         if (!rt && lifetime)
 499                 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 500                                         pref);
 501         else if (rt)
 502                 rt->rt6i_flags = RTF_ROUTEINFO |
 503                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 504
 505         if (rt) {
 506                 if (lifetime == 0xffffffff) {
 507                         rt->rt6i_flags &= ~RTF_EXPIRES;
 508                 } else {
 509                         rt->rt6i_expires = jiffies + HZ * lifetime;
 510                         rt->rt6i_flags |= RTF_EXPIRES;
 511                 }
 512                 dst_release(&rt->u.dst);
 513         }
 514         return 0;
 515 }
 516 #endif
 517
 518 #define BACKTRACK(saddr) \
 519 do { \
 520         if (rt == &ip6_null_entry) { \
 521                 struct fib6_node *pn; \
 522                 while (1) { \
 523                         if (fn->fn_flags & RTN_TL_ROOT) \
 524                                 goto out; \
 525                         pn = fn->parent; \
 526                         if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
 527                                 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
 528                         else \
 529                                 fn = pn; \
 530                         if (fn->fn_flags & RTN_RTINFO) \
 531                                 goto restart; \
 532                 } \
 533         } \
 534 } while(0)
 535
 536 static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
 537                                              struct flowi *fl, int flags)
 538 {
 539         struct fib6_node *fn;
 540         struct rt6_info *rt;
 541
 542         read_lock_bh(&table->tb6_lock);
 543         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
 544 restart:
 545         rt = fn->leaf;
 546         rt = rt6_device_match(rt, fl->oif, flags);
 547         BACKTRACK(&fl->fl6_src);
 548 out:
 549         dst_use(&rt->u.dst, jiffies);
 550         read_unlock_bh(&table->tb6_lock);
 551         return rt;
 552
 553 }
 554
 555 struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
 556                             int oif, int strict)
 557 {
 558         struct flowi fl = {
 559                 .oif = oif,
 560                 .nl_u = {
 561                         .ip6_u = {
 562                                 .daddr = *daddr,
 563                         },
 564                 },
 565         };
 566         struct dst_entry *dst;
 567         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 568
 569         if (saddr) {
 570                 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
 571                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 572         }
 573
 574         dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
 575         if (dst->error == 0)
 576                 return (struct rt6_info *) dst;
 577
 578         dst_release(dst);
 579
 580         return NULL;
 581 }
 582
 583 EXPORT_SYMBOL(rt6_lookup);
 584
 585 /* ip6_ins_rt is called with FREE table->tb6_lock.
 586    It takes new route entry, the addition fails by any reason the
 587    route is freed. In any case, if caller does not hold it, it may
 588    be destroyed.
 589  */
 590
 591 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
 592 {
 593         int err;
 594         struct fib6_table *table;
 595
 596         table = rt->rt6i_table;
 597         write_lock_bh(&table->tb6_lock);
 598         err = fib6_add(&table->tb6_root, rt, info);
 599         write_unlock_bh(&table->tb6_lock);
 600
 601         return err;
 602 }
 603
 604 int ip6_ins_rt(struct rt6_info *rt)
 605 {
 606         struct nl_info info = {
 607                 .nl_net = &init_net,
 608         };
 609         return __ip6_ins_rt(rt, &info);
 610 }
 611
 612 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
 613                                       struct in6_addr *saddr)
 614 {
 615         struct rt6_info *rt;
 616
 617         /*
 618          *      Clone the route.
 619          */
 620
 621         rt = ip6_rt_copy(ort);
 622
 623         if (rt) {
 624                 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
 625                         if (rt->rt6i_dst.plen != 128 &&
 626                             ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
 627                                 rt->rt6i_flags |= RTF_ANYCAST;
 628                         ipv6_addr_copy(&rt->rt6i_gateway, daddr);
 629                 }
 630
 631                 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
 632                 rt->rt6i_dst.plen = 128;
 633                 rt->rt6i_flags |= RTF_CACHE;
 634                 rt->u.dst.flags |= DST_HOST;
 635
 636 #ifdef CONFIG_IPV6_SUBTREES
 637                 if (rt->rt6i_src.plen && saddr) {
 638                         ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
 639                         rt->rt6i_src.plen = 128;
 640                 }
 641 #endif
 642
 643                 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
 644
 645         }
 646
 647         return rt;
 648 }
 649
 650 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
 651 {
 652         struct rt6_info *rt = ip6_rt_copy(ort);
 653         if (rt) {
 654                 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
 655                 rt->rt6i_dst.plen = 128;
 656                 rt->rt6i_flags |= RTF_CACHE;
 657                 rt->u.dst.flags |= DST_HOST;
 658                 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
 659         }
 660         return rt;
 661 }
 662
 663 static struct rt6_info *ip6_pol_route(struct fib6_table *table, int oif,
 664                                             struct flowi *fl, int flags)
 665 {
 666         struct fib6_node *fn;
 667         struct rt6_info *rt, *nrt;
 668         int strict = 0;
 669         int attempts = 3;
 670         int err;
 671         int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
 672
 673         strict |= flags & RT6_LOOKUP_F_IFACE;
 674
 675 relookup:
 676         read_lock_bh(&table->tb6_lock);
 677
 678 restart_2:
 679         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
 680
 681 restart:
 682         rt = rt6_select(fn, oif, strict | reachable);
 683         BACKTRACK(&fl->fl6_src);
 684         if (rt == &ip6_null_entry ||
 685             rt->rt6i_flags & RTF_CACHE)
 686                 goto out;
 687
 688         dst_hold(&rt->u.dst);
 689         read_unlock_bh(&table->tb6_lock);
 690
 691         if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
 692                 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
 693         else {
 694 #if CLONE_OFFLINK_ROUTE
 695                 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
 696 #else
 697                 goto out2;
 698 #endif
 699         }
 700
 701         dst_release(&rt->u.dst);
 702         rt = nrt ? : &ip6_null_entry;
 703
 704         dst_hold(&rt->u.dst);
 705         if (nrt) {
 706                 err = ip6_ins_rt(nrt);
 707                 if (!err)
 708                         goto out2;
 709         }
 710
 711         if (--attempts <= 0)
 712                 goto out2;
 713
 714         /*
 715          * Race condition! In the gap, when table->tb6_lock was
 716          * released someone could insert this route.  Relookup.
 717          */
 718         dst_release(&rt->u.dst);
 719         goto relookup;
 720
 721 out:
 722         if (reachable) {
 723                 reachable = 0;
 724                 goto restart_2;
 725         }
 726         dst_hold(&rt->u.dst);
 727         read_unlock_bh(&table->tb6_lock);
 728 out2:
 729         rt->u.dst.lastuse = jiffies;
 730         rt->u.dst.__use++;
 731
 732         return rt;
 733 }
 734
 735 static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
 736                                             struct flowi *fl, int flags)
 737 {
 738         return ip6_pol_route(table, fl->iif, fl, flags);
 739 }
 740
 741 void ip6_route_input(struct sk_buff *skb)
 742 {
 743         struct ipv6hdr *iph = ipv6_hdr(skb);
 744         int flags = RT6_LOOKUP_F_HAS_SADDR;
 745         struct flowi fl = {
 746                 .iif = skb->dev->ifindex,
 747                 .nl_u = {
 748                         .ip6_u = {
 749                                 .daddr = iph->daddr,
 750                                 .saddr = iph->saddr,
 751                                 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
 752                         },
 753                 },
 754                 .mark = skb->mark,
 755                 .proto = iph->nexthdr,
 756         };
 757
 758         if (rt6_need_strict(&iph->daddr))
 759                 flags |= RT6_LOOKUP_F_IFACE;
 760
 761         skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
 762 }
 763
 764 static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
 765                                              struct flowi *fl, int flags)
 766 {
 767         return ip6_pol_route(table, fl->oif, fl, flags);
 768 }
 769
 770 struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
 771 {
 772         int flags = 0;
 773
 774         if (rt6_need_strict(&fl->fl6_dst))
 775                 flags |= RT6_LOOKUP_F_IFACE;
 776
 777         if (!ipv6_addr_any(&fl->fl6_src))
 778                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 779
 780         return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
 781 }
 782
 783 EXPORT_SYMBOL(ip6_route_output);
 784
 785 int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
 786 {
 787         struct rt6_info *ort = (struct rt6_info *) *dstp;
 788         struct rt6_info *rt = (struct rt6_info *)
 789                 dst_alloc(&ip6_dst_blackhole_ops);
 790         struct dst_entry *new = NULL;
 791
 792         if (rt) {
 793                 new = &rt->u.dst;
 794
 795                 atomic_set(&new->__refcnt, 1);
 796                 new->__use = 1;
 797                 new->input = dst_discard;
 798                 new->output = dst_discard;
 799
 800                 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
 801                 new->dev = ort->u.dst.dev;
 802                 if (new->dev)
 803                         dev_hold(new->dev);
 804                 rt->rt6i_idev = ort->rt6i_idev;
 805                 if (rt->rt6i_idev)
 806                         in6_dev_hold(rt->rt6i_idev);
 807                 rt->rt6i_expires = 0;
 808
 809                 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
 810                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
 811                 rt->rt6i_metric = 0;
 812
 813                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
 814 #ifdef CONFIG_IPV6_SUBTREES
 815                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
 816 #endif
 817
 818                 dst_free(new);
 819         }
 820
 821         dst_release(*dstp);
 822         *dstp = new;
 823         return (new ? 0 : -ENOMEM);
 824 }
 825 EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
 826
 827 /*
 828  *      Destination cache support functions
 829  */
 830
 831 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
 832 {
 833         struct rt6_info *rt;
 834
 835         rt = (struct rt6_info *) dst;
 836
 837         if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
 838                 return dst;
 839
 840         return NULL;
 841 }
 842
 843 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
 844 {
 845         struct rt6_info *rt = (struct rt6_info *) dst;
 846
 847         if (rt) {
 848                 if (rt->rt6i_flags & RTF_CACHE)
 849                         ip6_del_rt(rt);
 850                 else
 851                         dst_release(dst);
 852         }
 853         return NULL;
 854 }
 855
 856 static void ip6_link_failure(struct sk_buff *skb)
 857 {
 858         struct rt6_info *rt;
 859
 860         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
 861
 862         rt = (struct rt6_info *) skb->dst;
 863         if (rt) {
 864                 if (rt->rt6i_flags&RTF_CACHE) {
 865                         dst_set_expires(&rt->u.dst, 0);
 866                         rt->rt6i_flags |= RTF_EXPIRES;
 867                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
 868                         rt->rt6i_node->fn_sernum = -1;
 869         }
 870 }
 871
 872 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
 873 {
 874         struct rt6_info *rt6 = (struct rt6_info*)dst;
 875
 876         if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
 877                 rt6->rt6i_flags |= RTF_MODIFIED;
 878                 if (mtu < IPV6_MIN_MTU) {
 879                         mtu = IPV6_MIN_MTU;
 880                         dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
 881                 }
 882                 dst->metrics[RTAX_MTU-1] = mtu;
 883                 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
 884         }
 885 }
 886
 887 static int ipv6_get_mtu(struct net_device *dev);
 888
 889 static inline unsigned int ipv6_advmss(unsigned int mtu)
 890 {
 891         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
 892
 893         if (mtu < init_net.ipv6.sysctl.ip6_rt_min_advmss)
 894                 mtu = init_net.ipv6.sysctl.ip6_rt_min_advmss;
 895
 896         /*
 897          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
 898          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
 899          * IPV6_MAXPLEN is also valid and means: "any MSS,
 900          * rely only on pmtu discovery"
 901          */
 902         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
 903                 mtu = IPV6_MAXPLEN;
 904         return mtu;
 905 }
 906
 907 static struct dst_entry *ndisc_dst_gc_list;
 908 static DEFINE_SPINLOCK(ndisc_lock);
 909
 910 struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
 911                                   struct neighbour *neigh,
 912                                   struct in6_addr *addr,
 913                                   int (*output)(struct sk_buff *))
 914 {
 915         struct rt6_info *rt;
 916         struct inet6_dev *idev = in6_dev_get(dev);
 917
 918         if (unlikely(idev == NULL))
 919                 return NULL;
 920
 921         rt = ip6_dst_alloc();
 922         if (unlikely(rt == NULL)) {
 923                 in6_dev_put(idev);
 924                 goto out;
 925         }
 926
 927         dev_hold(dev);
 928         if (neigh)
 929                 neigh_hold(neigh);
 930         else
 931                 neigh = ndisc_get_neigh(dev, addr);
 932
 933         rt->rt6i_dev      = dev;
 934         rt->rt6i_idev     = idev;
 935         rt->rt6i_nexthop  = neigh;
 936         atomic_set(&rt->u.dst.__refcnt, 1);
 937         rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
 938         rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
 939         rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
 940         rt->u.dst.output  = output;
 941
 942 #if 0   /* there's no chance to use these for ndisc */
 943         rt->u.dst.flags   = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
 944                                 ? DST_HOST
 945                                 : 0;
 946         ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
 947         rt->rt6i_dst.plen = 128;
 948 #endif
 949
 950         spin_lock_bh(&ndisc_lock);
 951         rt->u.dst.next = ndisc_dst_gc_list;
 952         ndisc_dst_gc_list = &rt->u.dst;
 953         spin_unlock_bh(&ndisc_lock);
 954
 955         fib6_force_start_gc();
 956
 957 out:
 958         return &rt->u.dst;
 959 }
 960
 961 int ndisc_dst_gc(int *more)
 962 {
 963         struct dst_entry *dst, *next, **pprev;
 964         int freed;
 965
 966         next = NULL;
 967         freed = 0;
 968
 969         spin_lock_bh(&ndisc_lock);
 970         pprev = &ndisc_dst_gc_list;
 971
 972         while ((dst = *pprev) != NULL) {
 973                 if (!atomic_read(&dst->__refcnt)) {
 974                         *pprev = dst->next;
 975                         dst_free(dst);
 976                         freed++;
 977                 } else {
 978                         pprev = &dst->next;
 979                         (*more)++;
 980                 }
 981         }
 982
 983         spin_unlock_bh(&ndisc_lock);
 984
 985         return freed;
 986 }
 987
 988 static int ip6_dst_gc(struct dst_ops *ops)
 989 {
 990         static unsigned expire = 30*HZ;
 991         static unsigned long last_gc;
 992         unsigned long now = jiffies;
 993
 994         if (time_after(last_gc + init_net.ipv6.sysctl.ip6_rt_gc_min_interval, now) &&
 995             atomic_read(&ip6_dst_ops.entries) <= init_net.ipv6.sysctl.ip6_rt_max_size)
 996                 goto out;
 997
 998         expire++;
 999         fib6_run_gc(expire);
1000         last_gc = now;
1001         if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
1002                 expire = init_net.ipv6.sysctl.ip6_rt_gc_timeout>>1;
1003
1004 out:
1005         expire -= expire>>init_net.ipv6.sysctl.ip6_rt_gc_elasticity;
1006         return (atomic_read(&ip6_dst_ops.entries) > init_net.ipv6.sysctl.ip6_rt_max_size);
1007 }
1008
1009 /* Clean host part of a prefix. Not necessary in radix tree,
1010    but results in cleaner routing tables.
1011
1012    Remove it only when all the things will work!
1013  */
1014
1015 static int ipv6_get_mtu(struct net_device *dev)
1016 {
1017         int mtu = IPV6_MIN_MTU;
1018         struct inet6_dev *idev;
1019
1020         idev = in6_dev_get(dev);
1021         if (idev) {
1022                 mtu = idev->cnf.mtu6;
1023                 in6_dev_put(idev);
1024         }
1025         return mtu;
1026 }
1027
1028 int ipv6_get_hoplimit(struct net_device *dev)
1029 {
1030         int hoplimit = ipv6_devconf.hop_limit;
1031         struct inet6_dev *idev;
1032
1033         idev = in6_dev_get(dev);
1034         if (idev) {
1035                 hoplimit = idev->cnf.hop_limit;
1036                 in6_dev_put(idev);
1037         }
1038         return hoplimit;
1039 }
1040
1041 /*
1042  *
1043  */
1044
1045 int ip6_route_add(struct fib6_config *cfg)
1046 {
1047         int err;
1048         struct rt6_info *rt = NULL;
1049         struct net_device *dev = NULL;
1050         struct inet6_dev *idev = NULL;
1051         struct fib6_table *table;
1052         int addr_type;
1053
1054         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1055                 return -EINVAL;
1056 #ifndef CONFIG_IPV6_SUBTREES
1057         if (cfg->fc_src_len)
1058                 return -EINVAL;
1059 #endif
1060         if (cfg->fc_ifindex) {
1061                 err = -ENODEV;
1062                 dev = dev_get_by_index(&init_net, cfg->fc_ifindex);
1063                 if (!dev)
1064                         goto out;
1065                 idev = in6_dev_get(dev);
1066                 if (!idev)
1067                         goto out;
1068         }
1069
1070         if (cfg->fc_metric == 0)
1071                 cfg->fc_metric = IP6_RT_PRIO_USER;
1072
1073         table = fib6_new_table(cfg->fc_table);
1074         if (table == NULL) {
1075                 err = -ENOBUFS;
1076                 goto out;
1077         }
1078
1079         rt = ip6_dst_alloc();
1080
1081         if (rt == NULL) {
1082                 err = -ENOMEM;
1083                 goto out;
1084         }
1085
1086         rt->u.dst.obsolete = -1;
1087         rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1088
1089         if (cfg->fc_protocol == RTPROT_UNSPEC)
1090                 cfg->fc_protocol = RTPROT_BOOT;
1091         rt->rt6i_protocol = cfg->fc_protocol;
1092
1093         addr_type = ipv6_addr_type(&cfg->fc_dst);
1094
1095         if (addr_type & IPV6_ADDR_MULTICAST)
1096                 rt->u.dst.input = ip6_mc_input;
1097         else
1098                 rt->u.dst.input = ip6_forward;
1099
1100         rt->u.dst.output = ip6_output;
1101
1102         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1103         rt->rt6i_dst.plen = cfg->fc_dst_len;
1104         if (rt->rt6i_dst.plen == 128)
1105                rt->u.dst.flags = DST_HOST;
1106
1107 #ifdef CONFIG_IPV6_SUBTREES
1108         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1109         rt->rt6i_src.plen = cfg->fc_src_len;
1110 #endif
1111
1112         rt->rt6i_metric = cfg->fc_metric;
1113
1114         /* We cannot add true routes via loopback here,
1115            they would result in kernel looping; promote them to reject routes
1116          */
1117         if ((cfg->fc_flags & RTF_REJECT) ||
1118             (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1119                 /* hold loopback dev/idev if we haven't done so. */
1120                 if (dev != init_net.loopback_dev) {
1121                         if (dev) {
1122                                 dev_put(dev);
1123                                 in6_dev_put(idev);
1124                         }
1125                         dev = init_net.loopback_dev;
1126                         dev_hold(dev);
1127                         idev = in6_dev_get(dev);
1128                         if (!idev) {
1129                                 err = -ENODEV;
1130                                 goto out;
1131                         }
1132                 }
1133                 rt->u.dst.output = ip6_pkt_discard_out;
1134                 rt->u.dst.input = ip6_pkt_discard;
1135                 rt->u.dst.error = -ENETUNREACH;
1136                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1137                 goto install_route;
1138         }
1139
1140         if (cfg->fc_flags & RTF_GATEWAY) {
1141                 struct in6_addr *gw_addr;
1142                 int gwa_type;
1143
1144                 gw_addr = &cfg->fc_gateway;
1145                 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1146                 gwa_type = ipv6_addr_type(gw_addr);
1147
1148                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1149                         struct rt6_info *grt;
1150
1151                         /* IPv6 strictly inhibits using not link-local
1152                            addresses as nexthop address.
1153                            Otherwise, router will not able to send redirects.
1154                            It is very good, but in some (rare!) circumstances
1155                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1156                            some exceptions. --ANK
1157                          */
1158                         err = -EINVAL;
1159                         if (!(gwa_type&IPV6_ADDR_UNICAST))
1160                                 goto out;
1161
1162                         grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1163
1164                         err = -EHOSTUNREACH;
1165                         if (grt == NULL)
1166                                 goto out;
1167                         if (dev) {
1168                                 if (dev != grt->rt6i_dev) {
1169                                         dst_release(&grt->u.dst);
1170                                         goto out;
1171                                 }
1172                         } else {
1173                                 dev = grt->rt6i_dev;
1174                                 idev = grt->rt6i_idev;
1175                                 dev_hold(dev);
1176                                 in6_dev_hold(grt->rt6i_idev);
1177                         }
1178                         if (!(grt->rt6i_flags&RTF_GATEWAY))
1179                                 err = 0;
1180                         dst_release(&grt->u.dst);
1181
1182                         if (err)
1183                                 goto out;
1184                 }
1185                 err = -EINVAL;
1186                 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1187                         goto out;
1188         }
1189
1190         err = -ENODEV;
1191         if (dev == NULL)
1192                 goto out;
1193
1194         if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1195                 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1196                 if (IS_ERR(rt->rt6i_nexthop)) {
1197                         err = PTR_ERR(rt->rt6i_nexthop);
1198                         rt->rt6i_nexthop = NULL;
1199                         goto out;
1200                 }
1201         }
1202
1203         rt->rt6i_flags = cfg->fc_flags;
1204
1205 install_route:
1206         if (cfg->fc_mx) {
1207                 struct nlattr *nla;
1208                 int remaining;
1209
1210                 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1211                         int type = nla_type(nla);
1212
1213                         if (type) {
1214                                 if (type > RTAX_MAX) {
1215                                         err = -EINVAL;
1216                                         goto out;
1217                                 }
1218
1219                                 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1220                         }
1221                 }
1222         }
1223
1224         if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1225                 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1226         if (!rt->u.dst.metrics[RTAX_MTU-1])
1227                 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1228         if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1229                 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1230         rt->u.dst.dev = dev;
1231         rt->rt6i_idev = idev;
1232         rt->rt6i_table = table;
1233         return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1234
1235 out:
1236         if (dev)
1237                 dev_put(dev);
1238         if (idev)
1239                 in6_dev_put(idev);
1240         if (rt)
1241                 dst_free(&rt->u.dst);
1242         return err;
1243 }
1244
1245 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1246 {
1247         int err;
1248         struct fib6_table *table;
1249
1250         if (rt == &ip6_null_entry)
1251                 return -ENOENT;
1252
1253         table = rt->rt6i_table;
1254         write_lock_bh(&table->tb6_lock);
1255
1256         err = fib6_del(rt, info);
1257         dst_release(&rt->u.dst);
1258
1259         write_unlock_bh(&table->tb6_lock);
1260
1261         return err;
1262 }
1263
1264 int ip6_del_rt(struct rt6_info *rt)
1265 {
1266         struct nl_info info = {
1267                 .nl_net = &init_net,
1268         };
1269         return __ip6_del_rt(rt, &info);
1270 }
1271
1272 static int ip6_route_del(struct fib6_config *cfg)
1273 {
1274         struct fib6_table *table;
1275         struct fib6_node *fn;
1276         struct rt6_info *rt;
1277         int err = -ESRCH;
1278
1279         table = fib6_get_table(cfg->fc_table);
1280         if (table == NULL)
1281                 return err;
1282
1283         read_lock_bh(&table->tb6_lock);
1284
1285         fn = fib6_locate(&table->tb6_root,
1286                          &cfg->fc_dst, cfg->fc_dst_len,
1287                          &cfg->fc_src, cfg->fc_src_len);
1288
1289         if (fn) {
1290                 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1291                         if (cfg->fc_ifindex &&
1292                             (rt->rt6i_dev == NULL ||
1293                              rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1294                                 continue;
1295                         if (cfg->fc_flags & RTF_GATEWAY &&
1296                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1297                                 continue;
1298                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1299                                 continue;
1300                         dst_hold(&rt->u.dst);
1301                         read_unlock_bh(&table->tb6_lock);
1302
1303                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1304                 }
1305         }
1306         read_unlock_bh(&table->tb6_lock);
1307
1308         return err;
1309 }
1310
1311 /*
1312  *      Handle redirects
1313  */
1314 struct ip6rd_flowi {
1315         struct flowi fl;
1316         struct in6_addr gateway;
1317 };
1318
1319 static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
1320                                              struct flowi *fl,
1321                                              int flags)
1322 {
1323         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1324         struct rt6_info *rt;
1325         struct fib6_node *fn;
1326
1327         /*
1328          * Get the "current" route for this destination and
1329          * check if the redirect has come from approriate router.
1330          *
1331          * RFC 2461 specifies that redirects should only be
1332          * accepted if they come from the nexthop to the target.
1333          * Due to the way the routes are chosen, this notion
1334          * is a bit fuzzy and one might need to check all possible
1335          * routes.
1336          */
1337
1338         read_lock_bh(&table->tb6_lock);
1339         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1340 restart:
1341         for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1342                 /*
1343                  * Current route is on-link; redirect is always invalid.
1344                  *
1345                  * Seems, previous statement is not true. It could
1346                  * be node, which looks for us as on-link (f.e. proxy ndisc)
1347                  * But then router serving it might decide, that we should
1348                  * know truth 8)8) --ANK (980726).
1349                  */
1350                 if (rt6_check_expired(rt))
1351                         continue;
1352                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1353                         continue;
1354                 if (fl->oif != rt->rt6i_dev->ifindex)
1355                         continue;
1356                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1357                         continue;
1358                 break;
1359         }
1360
1361         if (!rt)
1362                 rt = &ip6_null_entry;
1363         BACKTRACK(&fl->fl6_src);
1364 out:
1365         dst_hold(&rt->u.dst);
1366
1367         read_unlock_bh(&table->tb6_lock);
1368
1369         return rt;
1370 };
1371
1372 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1373                                            struct in6_addr *src,
1374                                            struct in6_addr *gateway,
1375                                            struct net_device *dev)
1376 {
1377         int flags = RT6_LOOKUP_F_HAS_SADDR;
1378         struct ip6rd_flowi rdfl = {
1379                 .fl = {
1380                         .oif = dev->ifindex,
1381                         .nl_u = {
1382                                 .ip6_u = {
1383                                         .daddr = *dest,
1384                                         .saddr = *src,
1385                                 },
1386                         },
1387                 },
1388                 .gateway = *gateway,
1389         };
1390
1391         if (rt6_need_strict(dest))
1392                 flags |= RT6_LOOKUP_F_IFACE;
1393
1394         return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
1395 }
1396
1397 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1398                   struct in6_addr *saddr,
1399                   struct neighbour *neigh, u8 *lladdr, int on_link)
1400 {
1401         struct rt6_info *rt, *nrt = NULL;
1402         struct netevent_redirect netevent;
1403
1404         rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1405
1406         if (rt == &ip6_null_entry) {
1407                 if (net_ratelimit())
1408                         printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1409                                "for redirect target\n");
1410                 goto out;
1411         }
1412
1413         /*
1414          *      We have finally decided to accept it.
1415          */
1416
1417         neigh_update(neigh, lladdr, NUD_STALE,
1418                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
1419                      NEIGH_UPDATE_F_OVERRIDE|
1420                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1421                                      NEIGH_UPDATE_F_ISROUTER))
1422                      );
1423
1424         /*
1425          * Redirect received -> path was valid.
1426          * Look, redirects are sent only in response to data packets,
1427          * so that this nexthop apparently is reachable. --ANK
1428          */
1429         dst_confirm(&rt->u.dst);
1430
1431         /* Duplicate redirect: silently ignore. */
1432         if (neigh == rt->u.dst.neighbour)
1433                 goto out;
1434
1435         nrt = ip6_rt_copy(rt);
1436         if (nrt == NULL)
1437                 goto out;
1438
1439         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1440         if (on_link)
1441                 nrt->rt6i_flags &= ~RTF_GATEWAY;
1442
1443         ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1444         nrt->rt6i_dst.plen = 128;
1445         nrt->u.dst.flags |= DST_HOST;
1446
1447         ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1448         nrt->rt6i_nexthop = neigh_clone(neigh);
1449         /* Reset pmtu, it may be better */
1450         nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1451         nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1452
1453         if (ip6_ins_rt(nrt))
1454                 goto out;
1455
1456         netevent.old = &rt->u.dst;
1457         netevent.new = &nrt->u.dst;
1458         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1459
1460         if (rt->rt6i_flags&RTF_CACHE) {
1461                 ip6_del_rt(rt);
1462                 return;
1463         }
1464
1465 out:
1466         dst_release(&rt->u.dst);
1467         return;
1468 }
1469
1470 /*
1471  *      Handle ICMP "packet too big" messages
1472  *      i.e. Path MTU discovery
1473  */
1474
1475 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1476                         struct net_device *dev, u32 pmtu)
1477 {
1478         struct rt6_info *rt, *nrt;
1479         int allfrag = 0;
1480
1481         rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1482         if (rt == NULL)
1483                 return;
1484
1485         if (pmtu >= dst_mtu(&rt->u.dst))
1486                 goto out;
1487
1488         if (pmtu < IPV6_MIN_MTU) {
1489                 /*
1490                  * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1491                  * MTU (1280) and a fragment header should always be included
1492                  * after a node receiving Too Big message reporting PMTU is
1493                  * less than the IPv6 Minimum Link MTU.
1494                  */
1495                 pmtu = IPV6_MIN_MTU;
1496                 allfrag = 1;
1497         }
1498
1499         /* New mtu received -> path was valid.
1500            They are sent only in response to data packets,
1501            so that this nexthop apparently is reachable. --ANK
1502          */
1503         dst_confirm(&rt->u.dst);
1504
1505         /* Host route. If it is static, it would be better
1506            not to override it, but add new one, so that
1507            when cache entry will expire old pmtu
1508            would return automatically.
1509          */
1510         if (rt->rt6i_flags & RTF_CACHE) {
1511                 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1512                 if (allfrag)
1513                         rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1514                 dst_set_expires(&rt->u.dst, init_net.ipv6.sysctl.ip6_rt_mtu_expires);
1515                 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1516                 goto out;
1517         }
1518
1519         /* Network route.
1520            Two cases are possible:
1521            1. It is connected route. Action: COW
1522            2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1523          */
1524         if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1525                 nrt = rt6_alloc_cow(rt, daddr, saddr);
1526         else
1527                 nrt = rt6_alloc_clone(rt, daddr);
1528
1529         if (nrt) {
1530                 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1531                 if (allfrag)
1532                         nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1533
1534                 /* According to RFC 1981, detecting PMTU increase shouldn't be
1535                  * happened within 5 mins, the recommended timer is 10 mins.
1536                  * Here this route expiration time is set to ip6_rt_mtu_expires
1537                  * which is 10 mins. After 10 mins the decreased pmtu is expired
1538                  * and detecting PMTU increase will be automatically happened.
1539                  */
1540                 dst_set_expires(&nrt->u.dst, init_net.ipv6.sysctl.ip6_rt_mtu_expires);
1541                 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1542
1543                 ip6_ins_rt(nrt);
1544         }
1545 out:
1546         dst_release(&rt->u.dst);
1547 }
1548
1549 /*
1550  *      Misc support functions
1551  */
1552
1553 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1554 {
1555         struct rt6_info *rt = ip6_dst_alloc();
1556
1557         if (rt) {
1558                 rt->u.dst.input = ort->u.dst.input;
1559                 rt->u.dst.output = ort->u.dst.output;
1560
1561                 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1562                 rt->u.dst.error = ort->u.dst.error;
1563                 rt->u.dst.dev = ort->u.dst.dev;
1564                 if (rt->u.dst.dev)
1565                         dev_hold(rt->u.dst.dev);
1566                 rt->rt6i_idev = ort->rt6i_idev;
1567                 if (rt->rt6i_idev)
1568                         in6_dev_hold(rt->rt6i_idev);
1569                 rt->u.dst.lastuse = jiffies;
1570                 rt->rt6i_expires = 0;
1571
1572                 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1573                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1574                 rt->rt6i_metric = 0;
1575
1576                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1577 #ifdef CONFIG_IPV6_SUBTREES
1578                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1579 #endif
1580                 rt->rt6i_table = ort->rt6i_table;
1581         }
1582         return rt;
1583 }
1584
1585 #ifdef CONFIG_IPV6_ROUTE_INFO
1586 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1587                                            struct in6_addr *gwaddr, int ifindex)
1588 {
1589         struct fib6_node *fn;
1590         struct rt6_info *rt = NULL;
1591         struct fib6_table *table;
1592
1593         table = fib6_get_table(RT6_TABLE_INFO);
1594         if (table == NULL)
1595                 return NULL;
1596
1597         write_lock_bh(&table->tb6_lock);
1598         fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1599         if (!fn)
1600                 goto out;
1601
1602         for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1603                 if (rt->rt6i_dev->ifindex != ifindex)
1604                         continue;
1605                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1606                         continue;
1607                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1608                         continue;
1609                 dst_hold(&rt->u.dst);
1610                 break;
1611         }
1612 out:
1613         write_unlock_bh(&table->tb6_lock);
1614         return rt;
1615 }
1616
1617 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1618                                            struct in6_addr *gwaddr, int ifindex,
1619                                            unsigned pref)
1620 {
1621         struct fib6_config cfg = {
1622                 .fc_table       = RT6_TABLE_INFO,
1623                 .fc_metric      = IP6_RT_PRIO_USER,
1624                 .fc_ifindex     = ifindex,
1625                 .fc_dst_len     = prefixlen,
1626                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1627                                   RTF_UP | RTF_PREF(pref),
1628         };
1629
1630         ipv6_addr_copy(&cfg.fc_dst, prefix);
1631         ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1632
1633         /* We should treat it as a default route if prefix length is 0. */
1634         if (!prefixlen)
1635                 cfg.fc_flags |= RTF_DEFAULT;
1636
1637         ip6_route_add(&cfg);
1638
1639         return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1640 }
1641 #endif
1642
1643 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1644 {
1645         struct rt6_info *rt;
1646         struct fib6_table *table;
1647
1648         table = fib6_get_table(RT6_TABLE_DFLT);
1649         if (table == NULL)
1650                 return NULL;
1651
1652         write_lock_bh(&table->tb6_lock);
1653         for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
1654                 if (dev == rt->rt6i_dev &&
1655                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1656                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
1657                         break;
1658         }
1659         if (rt)
1660                 dst_hold(&rt->u.dst);
1661         write_unlock_bh(&table->tb6_lock);
1662         return rt;
1663 }
1664
1665 EXPORT_SYMBOL(rt6_get_dflt_router);
1666
1667 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1668                                      struct net_device *dev,
1669                                      unsigned int pref)
1670 {
1671         struct fib6_config cfg = {
1672                 .fc_table       = RT6_TABLE_DFLT,
1673                 .fc_metric      = IP6_RT_PRIO_USER,
1674                 .fc_ifindex     = dev->ifindex,
1675                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1676                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1677         };
1678
1679         ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1680
1681         ip6_route_add(&cfg);
1682
1683         return rt6_get_dflt_router(gwaddr, dev);
1684 }
1685
1686 void rt6_purge_dflt_routers(void)
1687 {
1688         struct rt6_info *rt;
1689         struct fib6_table *table;
1690
1691         /* NOTE: Keep consistent with rt6_get_dflt_router */
1692         table = fib6_get_table(RT6_TABLE_DFLT);
1693         if (table == NULL)
1694                 return;
1695
1696 restart:
1697         read_lock_bh(&table->tb6_lock);
1698         for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
1699                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1700                         dst_hold(&rt->u.dst);
1701                         read_unlock_bh(&table->tb6_lock);
1702                         ip6_del_rt(rt);
1703                         goto restart;
1704                 }
1705         }
1706         read_unlock_bh(&table->tb6_lock);
1707 }
1708
1709 static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1710                                  struct fib6_config *cfg)
1711 {
1712         memset(cfg, 0, sizeof(*cfg));
1713
1714         cfg->fc_table = RT6_TABLE_MAIN;
1715         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1716         cfg->fc_metric = rtmsg->rtmsg_metric;
1717         cfg->fc_expires = rtmsg->rtmsg_info;
1718         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1719         cfg->fc_src_len = rtmsg->rtmsg_src_len;
1720         cfg->fc_flags = rtmsg->rtmsg_flags;
1721
1722         ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1723         ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1724         ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1725 }
1726
1727 int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1728 {
1729         struct fib6_config cfg;
1730         struct in6_rtmsg rtmsg;
1731         int err;
1732
1733         switch(cmd) {
1734         case SIOCADDRT:         /* Add a route */
1735         case SIOCDELRT:         /* Delete a route */
1736                 if (!capable(CAP_NET_ADMIN))
1737                         return -EPERM;
1738                 err = copy_from_user(&rtmsg, arg,
1739                                      sizeof(struct in6_rtmsg));
1740                 if (err)
1741                         return -EFAULT;
1742
1743                 rtmsg_to_fib6_config(&rtmsg, &cfg);
1744
1745                 rtnl_lock();
1746                 switch (cmd) {
1747                 case SIOCADDRT:
1748                         err = ip6_route_add(&cfg);
1749                         break;
1750                 case SIOCDELRT:
1751                         err = ip6_route_del(&cfg);
1752                         break;
1753                 default:
1754                         err = -EINVAL;
1755                 }
1756                 rtnl_unlock();
1757
1758                 return err;
1759         }
1760
1761         return -EINVAL;
1762 }
1763
1764 /*
1765  *      Drop the packet on the floor
1766  */
1767
1768 static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes)
1769 {
1770         int type;
1771         switch (ipstats_mib_noroutes) {
1772         case IPSTATS_MIB_INNOROUTES:
1773                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1774                 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) {
1775                         IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
1776                         break;
1777                 }
1778                 /* FALLTHROUGH */
1779         case IPSTATS_MIB_OUTNOROUTES:
1780                 IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes);
1781                 break;
1782         }
1783         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1784         kfree_skb(skb);
1785         return 0;
1786 }
1787
1788 static int ip6_pkt_discard(struct sk_buff *skb)
1789 {
1790         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1791 }
1792
1793 static int ip6_pkt_discard_out(struct sk_buff *skb)
1794 {
1795         skb->dev = skb->dst->dev;
1796         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1797 }
1798
1799 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1800
1801 static int ip6_pkt_prohibit(struct sk_buff *skb)
1802 {
1803         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1804 }
1805
1806 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1807 {
1808         skb->dev = skb->dst->dev;
1809         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1810 }
1811
1812 #endif
1813
1814 /*
1815  *      Allocate a dst for local (unicast / anycast) address.
1816  */
1817
1818 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1819                                     const struct in6_addr *addr,
1820                                     int anycast)
1821 {
1822         struct rt6_info *rt = ip6_dst_alloc();
1823
1824         if (rt == NULL)
1825                 return ERR_PTR(-ENOMEM);
1826
1827         dev_hold(init_net.loopback_dev);
1828         in6_dev_hold(idev);
1829
1830         rt->u.dst.flags = DST_HOST;
1831         rt->u.dst.input = ip6_input;
1832         rt->u.dst.output = ip6_output;
1833         rt->rt6i_dev = init_net.loopback_dev;
1834         rt->rt6i_idev = idev;
1835         rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1836         rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1837         rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1838         rt->u.dst.obsolete = -1;
1839
1840         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1841         if (anycast)
1842                 rt->rt6i_flags |= RTF_ANYCAST;
1843         else
1844                 rt->rt6i_flags |= RTF_LOCAL;
1845         rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1846         if (rt->rt6i_nexthop == NULL) {
1847                 dst_free(&rt->u.dst);
1848                 return ERR_PTR(-ENOMEM);
1849         }
1850
1851         ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1852         rt->rt6i_dst.plen = 128;
1853         rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1854
1855         atomic_set(&rt->u.dst.__refcnt, 1);
1856
1857         return rt;
1858 }
1859
1860 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1861 {
1862         if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1863             rt != &ip6_null_entry) {
1864                 RT6_TRACE("deleted by ifdown %p\n", rt);
1865                 return -1;
1866         }
1867         return 0;
1868 }
1869
1870 void rt6_ifdown(struct net_device *dev)
1871 {
1872         fib6_clean_all(fib6_ifdown, 0, dev);
1873 }
1874
1875 struct rt6_mtu_change_arg
1876 {
1877         struct net_device *dev;
1878         unsigned mtu;
1879 };
1880
1881 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1882 {
1883         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1884         struct inet6_dev *idev;
1885
1886         /* In IPv6 pmtu discovery is not optional,
1887            so that RTAX_MTU lock cannot disable it.
1888            We still use this lock to block changes
1889            caused by addrconf/ndisc.
1890         */
1891
1892         idev = __in6_dev_get(arg->dev);
1893         if (idev == NULL)
1894                 return 0;
1895
1896         /* For administrative MTU increase, there is no way to discover
1897            IPv6 PMTU increase, so PMTU increase should be updated here.
1898            Since RFC 1981 doesn't include administrative MTU increase
1899            update PMTU increase is a MUST. (i.e. jumbo frame)
1900          */
1901         /*
1902            If new MTU is less than route PMTU, this new MTU will be the
1903            lowest MTU in the path, update the route PMTU to reflect PMTU
1904            decreases; if new MTU is greater than route PMTU, and the
1905            old MTU is the lowest MTU in the path, update the route PMTU
1906            to reflect the increase. In this case if the other nodes' MTU
1907            also have the lowest MTU, TOO BIG MESSAGE will be lead to
1908            PMTU discouvery.
1909          */
1910         if (rt->rt6i_dev == arg->dev &&
1911             !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1912             (dst_mtu(&rt->u.dst) >= arg->mtu ||
1913              (dst_mtu(&rt->u.dst) < arg->mtu &&
1914               dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) {
1915                 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1916                 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
1917         }
1918         return 0;
1919 }
1920
1921 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1922 {
1923         struct rt6_mtu_change_arg arg = {
1924                 .dev = dev,
1925                 .mtu = mtu,
1926         };
1927
1928         fib6_clean_all(rt6_mtu_change_route, 0, &arg);
1929 }
1930
1931 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
1932         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
1933         [RTA_OIF]               = { .type = NLA_U32 },
1934         [RTA_IIF]               = { .type = NLA_U32 },
1935         [RTA_PRIORITY]          = { .type = NLA_U32 },
1936         [RTA_METRICS]           = { .type = NLA_NESTED },
1937 };
1938
1939 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1940                               struct fib6_config *cfg)
1941 {
1942         struct rtmsg *rtm;
1943         struct nlattr *tb[RTA_MAX+1];
1944         int err;
1945
1946         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
1947         if (err < 0)
1948                 goto errout;
1949
1950         err = -EINVAL;
1951         rtm = nlmsg_data(nlh);
1952         memset(cfg, 0, sizeof(*cfg));
1953
1954         cfg->fc_table = rtm->rtm_table;
1955         cfg->fc_dst_len = rtm->rtm_dst_len;
1956         cfg->fc_src_len = rtm->rtm_src_len;
1957         cfg->fc_flags = RTF_UP;
1958         cfg->fc_protocol = rtm->rtm_protocol;
1959
1960         if (rtm->rtm_type == RTN_UNREACHABLE)
1961                 cfg->fc_flags |= RTF_REJECT;
1962
1963         cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
1964         cfg->fc_nlinfo.nlh = nlh;
1965         cfg->fc_nlinfo.nl_net = skb->sk->sk_net;
1966
1967         if (tb[RTA_GATEWAY]) {
1968                 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
1969                 cfg->fc_flags |= RTF_GATEWAY;
1970         }
1971
1972         if (tb[RTA_DST]) {
1973                 int plen = (rtm->rtm_dst_len + 7) >> 3;
1974
1975                 if (nla_len(tb[RTA_DST]) < plen)
1976                         goto errout;
1977
1978                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
1979         }
1980
1981         if (tb[RTA_SRC]) {
1982                 int plen = (rtm->rtm_src_len + 7) >> 3;
1983
1984                 if (nla_len(tb[RTA_SRC]) < plen)
1985                         goto errout;
1986
1987                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
1988         }
1989
1990         if (tb[RTA_OIF])
1991                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
1992
1993         if (tb[RTA_PRIORITY])
1994                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
1995
1996         if (tb[RTA_METRICS]) {
1997                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
1998                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
1999         }
2000
2001         if (tb[RTA_TABLE])
2002                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2003
2004         err = 0;
2005 errout:
2006         return err;
2007 }
2008
2009 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2010 {
2011         struct net *net = skb->sk->sk_net;
2012         struct fib6_config cfg;
2013         int err;
2014
2015         if (net != &init_net)
2016                 return -EINVAL;
2017
2018         err = rtm_to_fib6_config(skb, nlh, &cfg);
2019         if (err < 0)
2020                 return err;
2021
2022         return ip6_route_del(&cfg);
2023 }
2024
2025 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2026 {
2027         struct net *net = skb->sk->sk_net;
2028         struct fib6_config cfg;
2029         int err;
2030
2031         if (net != &init_net)
2032                 return -EINVAL;
2033
2034         err = rtm_to_fib6_config(skb, nlh, &cfg);
2035         if (err < 0)
2036                 return err;
2037
2038         return ip6_route_add(&cfg);
2039 }
2040
2041 static inline size_t rt6_nlmsg_size(void)
2042 {
2043         return NLMSG_ALIGN(sizeof(struct rtmsg))
2044                + nla_total_size(16) /* RTA_SRC */
2045                + nla_total_size(16) /* RTA_DST */
2046                + nla_total_size(16) /* RTA_GATEWAY */
2047                + nla_total_size(16) /* RTA_PREFSRC */
2048                + nla_total_size(4) /* RTA_TABLE */
2049                + nla_total_size(4) /* RTA_IIF */
2050                + nla_total_size(4) /* RTA_OIF */
2051                + nla_total_size(4) /* RTA_PRIORITY */
2052                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2053                + nla_total_size(sizeof(struct rta_cacheinfo));
2054 }
2055
2056 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2057                          struct in6_addr *dst, struct in6_addr *src,
2058                          int iif, int type, u32 pid, u32 seq,
2059                          int prefix, unsigned int flags)
2060 {
2061         struct rtmsg *rtm;
2062         struct nlmsghdr *nlh;
2063         long expires;
2064         u32 table;
2065
2066         if (prefix) {   /* user wants prefix routes only */
2067                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2068                         /* success since this is not a prefix route */
2069                         return 1;
2070                 }
2071         }
2072
2073         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2074         if (nlh == NULL)
2075                 return -EMSGSIZE;
2076
2077         rtm = nlmsg_data(nlh);
2078         rtm->rtm_family = AF_INET6;
2079         rtm->rtm_dst_len = rt->rt6i_dst.plen;
2080         rtm->rtm_src_len = rt->rt6i_src.plen;
2081         rtm->rtm_tos = 0;
2082         if (rt->rt6i_table)
2083                 table = rt->rt6i_table->tb6_id;
2084         else
2085                 table = RT6_TABLE_UNSPEC;
2086         rtm->rtm_table = table;
2087         NLA_PUT_U32(skb, RTA_TABLE, table);
2088         if (rt->rt6i_flags&RTF_REJECT)
2089                 rtm->rtm_type = RTN_UNREACHABLE;
2090         else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2091                 rtm->rtm_type = RTN_LOCAL;
2092         else
2093                 rtm->rtm_type = RTN_UNICAST;
2094         rtm->rtm_flags = 0;
2095         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2096         rtm->rtm_protocol = rt->rt6i_protocol;
2097         if (rt->rt6i_flags&RTF_DYNAMIC)
2098                 rtm->rtm_protocol = RTPROT_REDIRECT;
2099         else if (rt->rt6i_flags & RTF_ADDRCONF)
2100                 rtm->rtm_protocol = RTPROT_KERNEL;
2101         else if (rt->rt6i_flags&RTF_DEFAULT)
2102                 rtm->rtm_protocol = RTPROT_RA;
2103
2104         if (rt->rt6i_flags&RTF_CACHE)
2105                 rtm->rtm_flags |= RTM_F_CLONED;
2106
2107         if (dst) {
2108                 NLA_PUT(skb, RTA_DST, 16, dst);
2109                 rtm->rtm_dst_len = 128;
2110         } else if (rtm->rtm_dst_len)
2111                 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2112 #ifdef CONFIG_IPV6_SUBTREES
2113         if (src) {
2114                 NLA_PUT(skb, RTA_SRC, 16, src);
2115                 rtm->rtm_src_len = 128;
2116         } else if (rtm->rtm_src_len)
2117                 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2118 #endif
2119         if (iif)
2120                 NLA_PUT_U32(skb, RTA_IIF, iif);
2121         else if (dst) {
2122                 struct in6_addr saddr_buf;
2123                 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2124                         NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2125         }
2126
2127         if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2128                 goto nla_put_failure;
2129
2130         if (rt->u.dst.neighbour)
2131                 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2132
2133         if (rt->u.dst.dev)
2134                 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2135
2136         NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2137
2138         expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
2139         if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2140                                expires, rt->u.dst.error) < 0)
2141                 goto nla_put_failure;
2142
2143         return nlmsg_end(skb, nlh);
2144
2145 nla_put_failure:
2146         nlmsg_cancel(skb, nlh);
2147         return -EMSGSIZE;
2148 }
2149
2150 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2151 {
2152         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2153         int prefix;
2154
2155         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2156                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2157                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2158         } else
2159                 prefix = 0;
2160
2161         return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2162                      NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2163                      prefix, NLM_F_MULTI);
2164 }
2165
2166 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2167 {
2168         struct net *net = in_skb->sk->sk_net;
2169         struct nlattr *tb[RTA_MAX+1];
2170         struct rt6_info *rt;
2171         struct sk_buff *skb;
2172         struct rtmsg *rtm;
2173         struct flowi fl;
2174         int err, iif = 0;
2175
2176         if (net != &init_net)
2177                 return -EINVAL;
2178
2179         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2180         if (err < 0)
2181                 goto errout;
2182
2183         err = -EINVAL;
2184         memset(&fl, 0, sizeof(fl));
2185
2186         if (tb[RTA_SRC]) {
2187                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2188                         goto errout;
2189
2190                 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2191         }
2192
2193         if (tb[RTA_DST]) {
2194                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2195                         goto errout;
2196
2197                 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2198         }
2199
2200         if (tb[RTA_IIF])
2201                 iif = nla_get_u32(tb[RTA_IIF]);
2202
2203         if (tb[RTA_OIF])
2204                 fl.oif = nla_get_u32(tb[RTA_OIF]);
2205
2206         if (iif) {
2207                 struct net_device *dev;
2208                 dev = __dev_get_by_index(&init_net, iif);
2209                 if (!dev) {
2210                         err = -ENODEV;
2211                         goto errout;
2212                 }
2213         }
2214
2215         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2216         if (skb == NULL) {
2217                 err = -ENOBUFS;
2218                 goto errout;
2219         }
2220
2221         /* Reserve room for dummy headers, this skb can pass
2222            through good chunk of routing engine.
2223          */
2224         skb_reset_mac_header(skb);
2225         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2226
2227         rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2228         skb->dst = &rt->u.dst;
2229
2230         err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2231                             RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2232                             nlh->nlmsg_seq, 0, 0);
2233         if (err < 0) {
2234                 kfree_skb(skb);
2235                 goto errout;
2236         }
2237
2238         err = rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
2239 errout:
2240         return err;
2241 }
2242
2243 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2244 {
2245         struct sk_buff *skb;
2246         u32 seq;
2247         int err;
2248
2249         err = -ENOBUFS;
2250         seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2251
2252         skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2253         if (skb == NULL)
2254                 goto errout;
2255
2256         err = rt6_fill_node(skb, rt, NULL, NULL, 0,
2257                                 event, info->pid, seq, 0, 0);
2258         if (err < 0) {
2259                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2260                 WARN_ON(err == -EMSGSIZE);
2261                 kfree_skb(skb);
2262                 goto errout;
2263         }
2264         err = rtnl_notify(skb, &init_net, info->pid,
2265                                 RTNLGRP_IPV6_ROUTE, info->nlh, gfp_any());
2266 errout:
2267         if (err < 0)
2268                 rtnl_set_sk_err(&init_net, RTNLGRP_IPV6_ROUTE, err);
2269 }
2270
2271 /*
2272  *      /proc
2273  */
2274
2275 #ifdef CONFIG_PROC_FS
2276
2277 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2278
2279 struct rt6_proc_arg
2280 {
2281         char *buffer;
2282         int offset;
2283         int length;
2284         int skip;
2285         int len;
2286 };
2287
2288 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2289 {
2290         struct seq_file *m = p_arg;
2291
2292         seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_dst.addr),
2293                    rt->rt6i_dst.plen);
2294
2295 #ifdef CONFIG_IPV6_SUBTREES
2296         seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_src.addr),
2297                    rt->rt6i_src.plen);
2298 #else
2299         seq_puts(m, "00000000000000000000000000000000 00 ");
2300 #endif
2301
2302         if (rt->rt6i_nexthop) {
2303                 seq_printf(m, NIP6_SEQFMT,
2304                            NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
2305         } else {
2306                 seq_puts(m, "00000000000000000000000000000000");
2307         }
2308         seq_printf(m, " %08x %08x %08x %08x %8s\n",
2309                    rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2310                    rt->u.dst.__use, rt->rt6i_flags,
2311                    rt->rt6i_dev ? rt->rt6i_dev->name : "");
2312         return 0;
2313 }
2314
2315 static int ipv6_route_show(struct seq_file *m, void *v)
2316 {
2317         fib6_clean_all(rt6_info_route, 0, m);
2318         return 0;
2319 }
2320
2321 static int ipv6_route_open(struct inode *inode, struct file *file)
2322 {
2323         return single_open(file, ipv6_route_show, NULL);
2324 }
2325
2326 static const struct file_operations ipv6_route_proc_fops = {
2327         .owner          = THIS_MODULE,
2328         .open           = ipv6_route_open,
2329         .read           = seq_read,
2330         .llseek         = seq_lseek,
2331         .release        = single_release,
2332 };
2333
2334 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2335 {
2336         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2337                       rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2338                       rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2339                       rt6_stats.fib_rt_cache,
2340                       atomic_read(&ip6_dst_ops.entries),
2341                       rt6_stats.fib_discarded_routes);
2342
2343         return 0;
2344 }
2345
2346 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2347 {
2348         return single_open(file, rt6_stats_seq_show, NULL);
2349 }
2350
2351 static const struct file_operations rt6_stats_seq_fops = {
2352         .owner   = THIS_MODULE,
2353         .open    = rt6_stats_seq_open,
2354         .read    = seq_read,
2355         .llseek  = seq_lseek,
2356         .release = single_release,
2357 };
2358
2359 static int ipv6_route_proc_init(struct net *net)
2360 {
2361         int ret = -ENOMEM;
2362         if (!proc_net_fops_create(net, "ipv6_route",
2363                                   0, &ipv6_route_proc_fops))
2364                 goto out;
2365
2366         if (!proc_net_fops_create(net, "rt6_stats",
2367                                   S_IRUGO, &rt6_stats_seq_fops))
2368                 goto out_ipv6_route;
2369
2370         ret = 0;
2371 out:
2372         return ret;
2373 out_ipv6_route:
2374         proc_net_remove(net, "ipv6_route");
2375         goto out;
2376 }
2377
2378 static void ipv6_route_proc_fini(struct net *net)
2379 {
2380         proc_net_remove(net, "ipv6_route");
2381         proc_net_remove(net, "rt6_stats");
2382 }
2383 #else
2384 static inline int ipv6_route_proc_init(struct net *net)
2385 {
2386         return 0;
2387 }
2388 static inline void ipv6_route_proc_fini(struct net *net)
2389 {
2390         return ;
2391 }
2392 #endif  /* CONFIG_PROC_FS */
2393
2394 #ifdef CONFIG_SYSCTL
2395
2396 static
2397 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2398                               void __user *buffer, size_t *lenp, loff_t *ppos)
2399 {
2400         int delay = init_net.ipv6.sysctl.flush_delay;
2401         if (write) {
2402                 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2403                 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay);
2404                 return 0;
2405         } else
2406                 return -EINVAL;
2407 }
2408
2409 ctl_table ipv6_route_table_template[] = {
2410         {
2411                 .procname       =       "flush",
2412                 .data           =       &init_net.ipv6.sysctl.flush_delay,
2413                 .maxlen         =       sizeof(int),
2414                 .mode           =       0200,
2415                 .proc_handler   =       &ipv6_sysctl_rtcache_flush
2416         },
2417         {
2418                 .ctl_name       =       NET_IPV6_ROUTE_GC_THRESH,
2419                 .procname       =       "gc_thresh",
2420                 .data           =       &ip6_dst_ops.gc_thresh,
2421                 .maxlen         =       sizeof(int),
2422                 .mode           =       0644,
2423                 .proc_handler   =       &proc_dointvec,
2424         },
2425         {
2426                 .ctl_name       =       NET_IPV6_ROUTE_MAX_SIZE,
2427                 .procname       =       "max_size",
2428                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
2429                 .maxlen         =       sizeof(int),
2430                 .mode           =       0644,
2431                 .proc_handler   =       &proc_dointvec,
2432         },
2433         {
2434                 .ctl_name       =       NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2435                 .procname       =       "gc_min_interval",
2436                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2437                 .maxlen         =       sizeof(int),
2438                 .mode           =       0644,
2439                 .proc_handler   =       &proc_dointvec_jiffies,
2440                 .strategy       =       &sysctl_jiffies,
2441         },
2442         {
2443                 .ctl_name       =       NET_IPV6_ROUTE_GC_TIMEOUT,
2444                 .procname       =       "gc_timeout",
2445                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2446                 .maxlen         =       sizeof(int),
2447                 .mode           =       0644,
2448                 .proc_handler   =       &proc_dointvec_jiffies,
2449                 .strategy       =       &sysctl_jiffies,
2450         },
2451         {
2452                 .ctl_name       =       NET_IPV6_ROUTE_GC_INTERVAL,
2453                 .procname       =       "gc_interval",
2454                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2455                 .maxlen         =       sizeof(int),
2456                 .mode           =       0644,
2457                 .proc_handler   =       &proc_dointvec_jiffies,
2458                 .strategy       =       &sysctl_jiffies,
2459         },
2460         {
2461                 .ctl_name       =       NET_IPV6_ROUTE_GC_ELASTICITY,
2462                 .procname       =       "gc_elasticity",
2463                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2464                 .maxlen         =       sizeof(int),
2465                 .mode           =       0644,
2466                 .proc_handler   =       &proc_dointvec_jiffies,
2467                 .strategy       =       &sysctl_jiffies,
2468         },
2469         {
2470                 .ctl_name       =       NET_IPV6_ROUTE_MTU_EXPIRES,
2471                 .procname       =       "mtu_expires",
2472                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2473                 .maxlen         =       sizeof(int),
2474                 .mode           =       0644,
2475                 .proc_handler   =       &proc_dointvec_jiffies,
2476                 .strategy       =       &sysctl_jiffies,
2477         },
2478         {
2479                 .ctl_name       =       NET_IPV6_ROUTE_MIN_ADVMSS,
2480                 .procname       =       "min_adv_mss",
2481                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2482                 .maxlen         =       sizeof(int),
2483                 .mode           =       0644,
2484                 .proc_handler   =       &proc_dointvec_jiffies,
2485                 .strategy       =       &sysctl_jiffies,
2486         },
2487         {
2488                 .ctl_name       =       NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2489                 .procname       =       "gc_min_interval_ms",
2490                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2491                 .maxlen         =       sizeof(int),
2492                 .mode           =       0644,
2493                 .proc_handler   =       &proc_dointvec_ms_jiffies,
2494                 .strategy       =       &sysctl_ms_jiffies,
2495         },
2496         { .ctl_name = 0 }
2497 };
2498
2499 struct ctl_table *ipv6_route_sysctl_init(struct net *net)
2500 {
2501         struct ctl_table *table;
2502
2503         table = kmemdup(ipv6_route_table_template,
2504                         sizeof(ipv6_route_table_template),
2505                         GFP_KERNEL);
2506         return table;
2507 }
2508 #endif
2509
2510 int __init ip6_route_init(void)
2511 {
2512         int ret;
2513
2514         ip6_dst_ops.kmem_cachep =
2515                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2516                                   SLAB_HWCACHE_ALIGN, NULL);
2517         if (!ip6_dst_ops.kmem_cachep)
2518                 return -ENOMEM;
2519
2520         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops.kmem_cachep;
2521
2522         ret = fib6_init();
2523         if (ret)
2524                 goto out_kmem_cache;
2525
2526         ret = ipv6_route_proc_init(&init_net);
2527         if (ret)
2528                 goto out_fib6_init;
2529
2530         ret = xfrm6_init();
2531         if (ret)
2532                 goto out_proc_init;
2533
2534         ret = fib6_rules_init();
2535         if (ret)
2536                 goto xfrm6_init;
2537
2538         ret = -ENOBUFS;
2539         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
2540             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
2541             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
2542                 goto fib6_rules_init;
2543
2544         ret = 0;
2545 out:
2546         return ret;
2547
2548 fib6_rules_init:
2549         fib6_rules_cleanup();
2550 xfrm6_init:
2551         xfrm6_fini();
2552 out_proc_init:
2553         ipv6_route_proc_fini(&init_net);
2554 out_fib6_init:
2555         rt6_ifdown(NULL);
2556         fib6_gc_cleanup();
2557 out_kmem_cache:
2558         kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
2559         goto out;
2560 }
2561
2562 void ip6_route_cleanup(void)
2563 {
2564         fib6_rules_cleanup();
2565         ipv6_route_proc_fini(&init_net);
2566         xfrm6_fini();
2567         rt6_ifdown(NULL);
2568         fib6_gc_cleanup();
2569         kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
2570 }