net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #include <linux/capability.h>
  28 #include <linux/errno.h>
  29 #include <linux/types.h>
  30 #include <linux/times.h>
  31 #include <linux/socket.h>
  32 #include <linux/sockios.h>
  33 #include <linux/net.h>
  34 #include <linux/route.h>
  35 #include <linux/netdevice.h>
  36 #include <linux/in6.h>
  37 #include <linux/mroute6.h>
  38 #include <linux/init.h>
  39 #include <linux/if_arp.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/seq_file.h>
  42 #include <linux/nsproxy.h>
  43 #include <linux/slab.h>
  44 #include <net/net_namespace.h>
  45 #include <net/snmp.h>
  46 #include <net/ipv6.h>
  47 #include <net/ip6_fib.h>
  48 #include <net/ip6_route.h>
  49 #include <net/ndisc.h>
  50 #include <net/addrconf.h>
  51 #include <net/tcp.h>
  52 #include <linux/rtnetlink.h>
  53 #include <net/dst.h>
  54 #include <net/xfrm.h>
  55 #include <net/netevent.h>
  56 #include <net/netlink.h>
  57
  58 #include <asm/uaccess.h>
  59
  60 #ifdef CONFIG_SYSCTL
  61 #include <linux/sysctl.h>
  62 #endif
  63
  64 /* Set to 3 to get tracing. */
  65 #define RT6_DEBUG 2
  66
  67 #if RT6_DEBUG >= 3
  68 #define RDBG(x) printk x
  69 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
  70 #else
  71 #define RDBG(x)
  72 #define RT6_TRACE(x...) do { ; } while (0)
  73 #endif
  74
  75 #define CLONE_OFFLINK_ROUTE 0
  76
  77 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
  78 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  79 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  80 static void             ip6_dst_destroy(struct dst_entry *);
  81 static void             ip6_dst_ifdown(struct dst_entry *,
  82                                        struct net_device *dev, int how);
  83 static int               ip6_dst_gc(struct dst_ops *ops);
  84
  85 static int              ip6_pkt_discard(struct sk_buff *skb);
  86 static int              ip6_pkt_discard_out(struct sk_buff *skb);
  87 static void             ip6_link_failure(struct sk_buff *skb);
  88 static void             ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
  89
  90 #ifdef CONFIG_IPV6_ROUTE_INFO
  91 static struct rt6_info *rt6_add_route_info(struct net *net,
  92                                            struct in6_addr *prefix, int prefixlen,
  93                                            struct in6_addr *gwaddr, int ifindex,
  94                                            unsigned pref);
  95 static struct rt6_info *rt6_get_route_info(struct net *net,
  96                                            struct in6_addr *prefix, int prefixlen,
  97                                            struct in6_addr *gwaddr, int ifindex);
  98 #endif
  99
 100 static struct dst_ops ip6_dst_ops_template = {
 101         .family                 =       AF_INET6,
 102         .protocol               =       cpu_to_be16(ETH_P_IPV6),
 103         .gc                     =       ip6_dst_gc,
 104         .gc_thresh              =       1024,
 105         .check                  =       ip6_dst_check,
 106         .destroy                =       ip6_dst_destroy,
 107         .ifdown                 =       ip6_dst_ifdown,
 108         .negative_advice        =       ip6_negative_advice,
 109         .link_failure           =       ip6_link_failure,
 110         .update_pmtu            =       ip6_rt_update_pmtu,
 111         .local_out              =       __ip6_local_out,
 112         .entries                =       ATOMIC_INIT(0),
 113 };
 114
 115 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
 116 {
 117 }
 118
 119 static struct dst_ops ip6_dst_blackhole_ops = {
 120         .family                 =       AF_INET6,
 121         .protocol               =       cpu_to_be16(ETH_P_IPV6),
 122         .destroy                =       ip6_dst_destroy,
 123         .check                  =       ip6_dst_check,
 124         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 125         .entries                =       ATOMIC_INIT(0),
 126 };
 127
 128 static struct rt6_info ip6_null_entry_template = {
 129         .u = {
 130                 .dst = {
 131                         .__refcnt       = ATOMIC_INIT(1),
 132                         .__use          = 1,
 133                         .obsolete       = -1,
 134                         .error          = -ENETUNREACH,
 135                         .metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
 136                         .input          = ip6_pkt_discard,
 137                         .output         = ip6_pkt_discard_out,
 138                 }
 139         },
 140         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 141         .rt6i_protocol  = RTPROT_KERNEL,
 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 static struct rt6_info ip6_prohibit_entry_template = {
 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                 }
 162         },
 163         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 164         .rt6i_protocol  = RTPROT_KERNEL,
 165         .rt6i_metric    = ~(u32) 0,
 166         .rt6i_ref       = ATOMIC_INIT(1),
 167 };
 168
 169 static struct rt6_info ip6_blk_hole_entry_template = {
 170         .u = {
 171                 .dst = {
 172                         .__refcnt       = ATOMIC_INIT(1),
 173                         .__use          = 1,
 174                         .obsolete       = -1,
 175                         .error          = -EINVAL,
 176                         .metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
 177                         .input          = dst_discard,
 178                         .output         = dst_discard,
 179                 }
 180         },
 181         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 182         .rt6i_protocol  = RTPROT_KERNEL,
 183         .rt6i_metric    = ~(u32) 0,
 184         .rt6i_ref       = ATOMIC_INIT(1),
 185 };
 186
 187 #endif
 188
 189 /* allocate dst with ip6_dst_ops */
 190 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops)
 191 {
 192         return (struct rt6_info *)dst_alloc(ops);
 193 }
 194
 195 static void ip6_dst_destroy(struct dst_entry *dst)
 196 {
 197         struct rt6_info *rt = (struct rt6_info *)dst;
 198         struct inet6_dev *idev = rt->rt6i_idev;
 199
 200         if (idev != NULL) {
 201                 rt->rt6i_idev = NULL;
 202                 in6_dev_put(idev);
 203         }
 204 }
 205
 206 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 207                            int how)
 208 {
 209         struct rt6_info *rt = (struct rt6_info *)dst;
 210         struct inet6_dev *idev = rt->rt6i_idev;
 211         struct net_device *loopback_dev =
 212                 dev_net(dev)->loopback_dev;
 213
 214         if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
 215                 struct inet6_dev *loopback_idev =
 216                         in6_dev_get(loopback_dev);
 217                 if (loopback_idev != NULL) {
 218                         rt->rt6i_idev = loopback_idev;
 219                         in6_dev_put(idev);
 220                 }
 221         }
 222 }
 223
 224 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
 225 {
 226         return (rt->rt6i_flags & RTF_EXPIRES &&
 227                 time_after(jiffies, rt->rt6i_expires));
 228 }
 229
 230 static inline int rt6_need_strict(struct in6_addr *daddr)
 231 {
 232         return (ipv6_addr_type(daddr) &
 233                 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK));
 234 }
 235
 236 /*
 237  *      Route lookup. Any table->tb6_lock is implied.
 238  */
 239
 240 static inline struct rt6_info *rt6_device_match(struct net *net,
 241                                                     struct rt6_info *rt,
 242                                                     struct in6_addr *saddr,
 243                                                     int oif,
 244                                                     int flags)
 245 {
 246         struct rt6_info *local = NULL;
 247         struct rt6_info *sprt;
 248
 249         if (!oif && ipv6_addr_any(saddr))
 250                 goto out;
 251
 252         for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
 253                 struct net_device *dev = sprt->rt6i_dev;
 254
 255                 if (oif) {
 256                         if (dev->ifindex == oif)
 257                                 return sprt;
 258                         if (dev->flags & IFF_LOOPBACK) {
 259                                 if (sprt->rt6i_idev == NULL ||
 260                                     sprt->rt6i_idev->dev->ifindex != oif) {
 261                                         if (flags & RT6_LOOKUP_F_IFACE && oif)
 262                                                 continue;
 263                                         if (local && (!oif ||
 264                                                       local->rt6i_idev->dev->ifindex == oif))
 265                                                 continue;
 266                                 }
 267                                 local = sprt;
 268                         }
 269                 } else {
 270                         if (ipv6_chk_addr(net, saddr, dev,
 271                                           flags & RT6_LOOKUP_F_IFACE))
 272                                 return sprt;
 273                 }
 274         }
 275
 276         if (oif) {
 277                 if (local)
 278                         return local;
 279
 280                 if (flags & RT6_LOOKUP_F_IFACE)
 281                         return net->ipv6.ip6_null_entry;
 282         }
 283 out:
 284         return rt;
 285 }
 286
 287 #ifdef CONFIG_IPV6_ROUTER_PREF
 288 static void rt6_probe(struct rt6_info *rt)
 289 {
 290         struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
 291         /*
 292          * Okay, this does not seem to be appropriate
 293          * for now, however, we need to check if it
 294          * is really so; aka Router Reachability Probing.
 295          *
 296          * Router Reachability Probe MUST be rate-limited
 297          * to no more than one per minute.
 298          */
 299         if (!neigh || (neigh->nud_state & NUD_VALID))
 300                 return;
 301         read_lock_bh(&neigh->lock);
 302         if (!(neigh->nud_state & NUD_VALID) &&
 303             time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
 304                 struct in6_addr mcaddr;
 305                 struct in6_addr *target;
 306
 307                 neigh->updated = jiffies;
 308                 read_unlock_bh(&neigh->lock);
 309
 310                 target = (struct in6_addr *)&neigh->primary_key;
 311                 addrconf_addr_solict_mult(target, &mcaddr);
 312                 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
 313         } else
 314                 read_unlock_bh(&neigh->lock);
 315 }
 316 #else
 317 static inline void rt6_probe(struct rt6_info *rt)
 318 {
 319 }
 320 #endif
 321
 322 /*
 323  * Default Router Selection (RFC 2461 6.3.6)
 324  */
 325 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 326 {
 327         struct net_device *dev = rt->rt6i_dev;
 328         if (!oif || dev->ifindex == oif)
 329                 return 2;
 330         if ((dev->flags & IFF_LOOPBACK) &&
 331             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 332                 return 1;
 333         return 0;
 334 }
 335
 336 static inline int rt6_check_neigh(struct rt6_info *rt)
 337 {
 338         struct neighbour *neigh = rt->rt6i_nexthop;
 339         int m;
 340         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 341             !(rt->rt6i_flags & RTF_GATEWAY))
 342                 m = 1;
 343         else if (neigh) {
 344                 read_lock_bh(&neigh->lock);
 345                 if (neigh->nud_state & NUD_VALID)
 346                         m = 2;
 347 #ifdef CONFIG_IPV6_ROUTER_PREF
 348                 else if (neigh->nud_state & NUD_FAILED)
 349                         m = 0;
 350 #endif
 351                 else
 352                         m = 1;
 353                 read_unlock_bh(&neigh->lock);
 354         } else
 355                 m = 0;
 356         return m;
 357 }
 358
 359 static int rt6_score_route(struct rt6_info *rt, int oif,
 360                            int strict)
 361 {
 362         int m, n;
 363
 364         m = rt6_check_dev(rt, oif);
 365         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 366                 return -1;
 367 #ifdef CONFIG_IPV6_ROUTER_PREF
 368         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 369 #endif
 370         n = rt6_check_neigh(rt);
 371         if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
 372                 return -1;
 373         return m;
 374 }
 375
 376 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 377                                    int *mpri, struct rt6_info *match)
 378 {
 379         int m;
 380
 381         if (rt6_check_expired(rt))
 382                 goto out;
 383
 384         m = rt6_score_route(rt, oif, strict);
 385         if (m < 0)
 386                 goto out;
 387
 388         if (m > *mpri) {
 389                 if (strict & RT6_LOOKUP_F_REACHABLE)
 390                         rt6_probe(match);
 391                 *mpri = m;
 392                 match = rt;
 393         } else if (strict & RT6_LOOKUP_F_REACHABLE) {
 394                 rt6_probe(rt);
 395         }
 396
 397 out:
 398         return match;
 399 }
 400
 401 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 402                                      struct rt6_info *rr_head,
 403                                      u32 metric, int oif, int strict)
 404 {
 405         struct rt6_info *rt, *match;
 406         int mpri = -1;
 407
 408         match = NULL;
 409         for (rt = rr_head; rt && rt->rt6i_metric == metric;
 410              rt = rt->u.dst.rt6_next)
 411                 match = find_match(rt, oif, strict, &mpri, match);
 412         for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
 413              rt = rt->u.dst.rt6_next)
 414                 match = find_match(rt, oif, strict, &mpri, match);
 415
 416         return match;
 417 }
 418
 419 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 420 {
 421         struct rt6_info *match, *rt0;
 422         struct net *net;
 423
 424         RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
 425                   __func__, fn->leaf, oif);
 426
 427         rt0 = fn->rr_ptr;
 428         if (!rt0)
 429                 fn->rr_ptr = rt0 = fn->leaf;
 430
 431         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
 432
 433         if (!match &&
 434             (strict & RT6_LOOKUP_F_REACHABLE)) {
 435                 struct rt6_info *next = rt0->u.dst.rt6_next;
 436
 437                 /* no entries matched; do round-robin */
 438                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 439                         next = fn->leaf;
 440
 441                 if (next != rt0)
 442                         fn->rr_ptr = next;
 443         }
 444
 445         RT6_TRACE("%s() => %p\n",
 446                   __func__, match);
 447
 448         net = dev_net(rt0->rt6i_dev);
 449         return (match ? match : net->ipv6.ip6_null_entry);
 450 }
 451
 452 #ifdef CONFIG_IPV6_ROUTE_INFO
 453 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 454                   struct in6_addr *gwaddr)
 455 {
 456         struct net *net = dev_net(dev);
 457         struct route_info *rinfo = (struct route_info *) opt;
 458         struct in6_addr prefix_buf, *prefix;
 459         unsigned int pref;
 460         unsigned long lifetime;
 461         struct rt6_info *rt;
 462
 463         if (len < sizeof(struct route_info)) {
 464                 return -EINVAL;
 465         }
 466
 467         /* Sanity check for prefix_len and length */
 468         if (rinfo->length > 3) {
 469                 return -EINVAL;
 470         } else if (rinfo->prefix_len > 128) {
 471                 return -EINVAL;
 472         } else if (rinfo->prefix_len > 64) {
 473                 if (rinfo->length < 2) {
 474                         return -EINVAL;
 475                 }
 476         } else if (rinfo->prefix_len > 0) {
 477                 if (rinfo->length < 1) {
 478                         return -EINVAL;
 479                 }
 480         }
 481
 482         pref = rinfo->route_pref;
 483         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 484                 return -EINVAL;
 485
 486         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 487
 488         if (rinfo->length == 3)
 489                 prefix = (struct in6_addr *)rinfo->prefix;
 490         else {
 491                 /* this function is safe */
 492                 ipv6_addr_prefix(&prefix_buf,
 493                                  (struct in6_addr *)rinfo->prefix,
 494                                  rinfo->prefix_len);
 495                 prefix = &prefix_buf;
 496         }
 497
 498         rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
 499                                 dev->ifindex);
 500
 501         if (rt && !lifetime) {
 502                 ip6_del_rt(rt);
 503                 rt = NULL;
 504         }
 505
 506         if (!rt && lifetime)
 507                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 508                                         pref);
 509         else if (rt)
 510                 rt->rt6i_flags = RTF_ROUTEINFO |
 511                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 512
 513         if (rt) {
 514                 if (!addrconf_finite_timeout(lifetime)) {
 515                         rt->rt6i_flags &= ~RTF_EXPIRES;
 516                 } else {
 517                         rt->rt6i_expires = jiffies + HZ * lifetime;
 518                         rt->rt6i_flags |= RTF_EXPIRES;
 519                 }
 520                 dst_release(&rt->u.dst);
 521         }
 522         return 0;
 523 }
 524 #endif
 525
 526 #define BACKTRACK(__net, saddr)                 \
 527 do { \
 528         if (rt == __net->ipv6.ip6_null_entry) { \
 529                 struct fib6_node *pn; \
 530                 while (1) { \
 531                         if (fn->fn_flags & RTN_TL_ROOT) \
 532                                 goto out; \
 533                         pn = fn->parent; \
 534                         if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
 535                                 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
 536                         else \
 537                                 fn = pn; \
 538                         if (fn->fn_flags & RTN_RTINFO) \
 539                                 goto restart; \
 540                 } \
 541         } \
 542 } while(0)
 543
 544 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 545                                              struct fib6_table *table,
 546                                              struct flowi *fl, int flags)
 547 {
 548         struct fib6_node *fn;
 549         struct rt6_info *rt;
 550
 551         read_lock_bh(&table->tb6_lock);
 552         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
 553 restart:
 554         rt = fn->leaf;
 555         rt = rt6_device_match(net, rt, &fl->fl6_src, fl->oif, flags);
 556         BACKTRACK(net, &fl->fl6_src);
 557 out:
 558         dst_use(&rt->u.dst, jiffies);
 559         read_unlock_bh(&table->tb6_lock);
 560         return rt;
 561
 562 }
 563
 564 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 565                             const struct in6_addr *saddr, int oif, int strict)
 566 {
 567         struct flowi fl = {
 568                 .oif = oif,
 569                 .nl_u = {
 570                         .ip6_u = {
 571                                 .daddr = *daddr,
 572                         },
 573                 },
 574         };
 575         struct dst_entry *dst;
 576         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 577
 578         if (saddr) {
 579                 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
 580                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 581         }
 582
 583         dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_lookup);
 584         if (dst->error == 0)
 585                 return (struct rt6_info *) dst;
 586
 587         dst_release(dst);
 588
 589         return NULL;
 590 }
 591
 592 EXPORT_SYMBOL(rt6_lookup);
 593
 594 /* ip6_ins_rt is called with FREE table->tb6_lock.
 595    It takes new route entry, the addition fails by any reason the
 596    route is freed. In any case, if caller does not hold it, it may
 597    be destroyed.
 598  */
 599
 600 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
 601 {
 602         int err;
 603         struct fib6_table *table;
 604
 605         table = rt->rt6i_table;
 606         write_lock_bh(&table->tb6_lock);
 607         err = fib6_add(&table->tb6_root, rt, info);
 608         write_unlock_bh(&table->tb6_lock);
 609
 610         return err;
 611 }
 612
 613 int ip6_ins_rt(struct rt6_info *rt)
 614 {
 615         struct nl_info info = {
 616                 .nl_net = dev_net(rt->rt6i_dev),
 617         };
 618         return __ip6_ins_rt(rt, &info);
 619 }
 620
 621 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
 622                                       struct in6_addr *saddr)
 623 {
 624         struct rt6_info *rt;
 625
 626         /*
 627          *      Clone the route.
 628          */
 629
 630         rt = ip6_rt_copy(ort);
 631
 632         if (rt) {
 633                 struct neighbour *neigh;
 634                 int attempts = !in_softirq();
 635
 636                 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
 637                         if (rt->rt6i_dst.plen != 128 &&
 638                             ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
 639                                 rt->rt6i_flags |= RTF_ANYCAST;
 640                         ipv6_addr_copy(&rt->rt6i_gateway, daddr);
 641                 }
 642
 643                 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
 644                 rt->rt6i_dst.plen = 128;
 645                 rt->rt6i_flags |= RTF_CACHE;
 646                 rt->u.dst.flags |= DST_HOST;
 647
 648 #ifdef CONFIG_IPV6_SUBTREES
 649                 if (rt->rt6i_src.plen && saddr) {
 650                         ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
 651                         rt->rt6i_src.plen = 128;
 652                 }
 653 #endif
 654
 655         retry:
 656                 neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
 657                 if (IS_ERR(neigh)) {
 658                         struct net *net = dev_net(rt->rt6i_dev);
 659                         int saved_rt_min_interval =
 660                                 net->ipv6.sysctl.ip6_rt_gc_min_interval;
 661                         int saved_rt_elasticity =
 662                                 net->ipv6.sysctl.ip6_rt_gc_elasticity;
 663
 664                         if (attempts-- > 0) {
 665                                 net->ipv6.sysctl.ip6_rt_gc_elasticity = 1;
 666                                 net->ipv6.sysctl.ip6_rt_gc_min_interval = 0;
 667
 668                                 ip6_dst_gc(&net->ipv6.ip6_dst_ops);
 669
 670                                 net->ipv6.sysctl.ip6_rt_gc_elasticity =
 671                                         saved_rt_elasticity;
 672                                 net->ipv6.sysctl.ip6_rt_gc_min_interval =
 673                                         saved_rt_min_interval;
 674                                 goto retry;
 675                         }
 676
 677                         if (net_ratelimit())
 678                                 printk(KERN_WARNING
 679                                        "Neighbour table overflow.\n");
 680                         dst_free(&rt->u.dst);
 681                         return NULL;
 682                 }
 683                 rt->rt6i_nexthop = neigh;
 684
 685         }
 686
 687         return rt;
 688 }
 689
 690 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
 691 {
 692         struct rt6_info *rt = ip6_rt_copy(ort);
 693         if (rt) {
 694                 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
 695                 rt->rt6i_dst.plen = 128;
 696                 rt->rt6i_flags |= RTF_CACHE;
 697                 rt->u.dst.flags |= DST_HOST;
 698                 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
 699         }
 700         return rt;
 701 }
 702
 703 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
 704                                       struct flowi *fl, int flags)
 705 {
 706         struct fib6_node *fn;
 707         struct rt6_info *rt, *nrt;
 708         int strict = 0;
 709         int attempts = 3;
 710         int err;
 711         int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
 712
 713         strict |= flags & RT6_LOOKUP_F_IFACE;
 714
 715 relookup:
 716         read_lock_bh(&table->tb6_lock);
 717
 718 restart_2:
 719         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
 720
 721 restart:
 722         rt = rt6_select(fn, oif, strict | reachable);
 723
 724         BACKTRACK(net, &fl->fl6_src);
 725         if (rt == net->ipv6.ip6_null_entry ||
 726             rt->rt6i_flags & RTF_CACHE)
 727                 goto out;
 728
 729         dst_hold(&rt->u.dst);
 730         read_unlock_bh(&table->tb6_lock);
 731
 732         if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
 733                 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
 734         else {
 735 #if CLONE_OFFLINK_ROUTE
 736                 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
 737 #else
 738                 goto out2;
 739 #endif
 740         }
 741
 742         dst_release(&rt->u.dst);
 743         rt = nrt ? : net->ipv6.ip6_null_entry;
 744
 745         dst_hold(&rt->u.dst);
 746         if (nrt) {
 747                 err = ip6_ins_rt(nrt);
 748                 if (!err)
 749                         goto out2;
 750         }
 751
 752         if (--attempts <= 0)
 753                 goto out2;
 754
 755         /*
 756          * Race condition! In the gap, when table->tb6_lock was
 757          * released someone could insert this route.  Relookup.
 758          */
 759         dst_release(&rt->u.dst);
 760         goto relookup;
 761
 762 out:
 763         if (reachable) {
 764                 reachable = 0;
 765                 goto restart_2;
 766         }
 767         dst_hold(&rt->u.dst);
 768         read_unlock_bh(&table->tb6_lock);
 769 out2:
 770         rt->u.dst.lastuse = jiffies;
 771         rt->u.dst.__use++;
 772
 773         return rt;
 774 }
 775
 776 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
 777                                             struct flowi *fl, int flags)
 778 {
 779         return ip6_pol_route(net, table, fl->iif, fl, flags);
 780 }
 781
 782 void ip6_route_input(struct sk_buff *skb)
 783 {
 784         struct ipv6hdr *iph = ipv6_hdr(skb);
 785         struct net *net = dev_net(skb->dev);
 786         int flags = RT6_LOOKUP_F_HAS_SADDR;
 787         struct flowi fl = {
 788                 .iif = skb->dev->ifindex,
 789                 .nl_u = {
 790                         .ip6_u = {
 791                                 .daddr = iph->daddr,
 792                                 .saddr = iph->saddr,
 793                                 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
 794                         },
 795                 },
 796                 .mark = skb->mark,
 797                 .proto = iph->nexthdr,
 798         };
 799
 800         if (rt6_need_strict(&iph->daddr) && skb->dev->type != ARPHRD_PIMREG)
 801                 flags |= RT6_LOOKUP_F_IFACE;
 802
 803         skb_dst_set(skb, fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input));
 804 }
 805
 806 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
 807                                              struct flowi *fl, int flags)
 808 {
 809         return ip6_pol_route(net, table, fl->oif, fl, flags);
 810 }
 811
 812 struct dst_entry * ip6_route_output(struct net *net, struct sock *sk,
 813                                     struct flowi *fl)
 814 {
 815         int flags = 0;
 816
 817         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl->fl6_dst))
 818                 flags |= RT6_LOOKUP_F_IFACE;
 819
 820         if (!ipv6_addr_any(&fl->fl6_src))
 821                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 822         else if (sk)
 823                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
 824
 825         return fib6_rule_lookup(net, fl, flags, ip6_pol_route_output);
 826 }
 827
 828 EXPORT_SYMBOL(ip6_route_output);
 829
 830 int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
 831 {
 832         struct rt6_info *ort = (struct rt6_info *) *dstp;
 833         struct rt6_info *rt = (struct rt6_info *)
 834                 dst_alloc(&ip6_dst_blackhole_ops);
 835         struct dst_entry *new = NULL;
 836
 837         if (rt) {
 838                 new = &rt->u.dst;
 839
 840                 atomic_set(&new->__refcnt, 1);
 841                 new->__use = 1;
 842                 new->input = dst_discard;
 843                 new->output = dst_discard;
 844
 845                 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
 846                 new->dev = ort->u.dst.dev;
 847                 if (new->dev)
 848                         dev_hold(new->dev);
 849                 rt->rt6i_idev = ort->rt6i_idev;
 850                 if (rt->rt6i_idev)
 851                         in6_dev_hold(rt->rt6i_idev);
 852                 rt->rt6i_expires = 0;
 853
 854                 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
 855                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
 856                 rt->rt6i_metric = 0;
 857
 858                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
 859 #ifdef CONFIG_IPV6_SUBTREES
 860                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
 861 #endif
 862
 863                 dst_free(new);
 864         }
 865
 866         dst_release(*dstp);
 867         *dstp = new;
 868         return (new ? 0 : -ENOMEM);
 869 }
 870 EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
 871
 872 /*
 873  *      Destination cache support functions
 874  */
 875
 876 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
 877 {
 878         struct rt6_info *rt;
 879
 880         rt = (struct rt6_info *) dst;
 881
 882         if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
 883                 return dst;
 884
 885         return NULL;
 886 }
 887
 888 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
 889 {
 890         struct rt6_info *rt = (struct rt6_info *) dst;
 891
 892         if (rt) {
 893                 if (rt->rt6i_flags & RTF_CACHE) {
 894                         if (rt6_check_expired(rt)) {
 895                                 ip6_del_rt(rt);
 896                                 dst = NULL;
 897                         }
 898                 } else {
 899                         dst_release(dst);
 900                         dst = NULL;
 901                 }
 902         }
 903         return dst;
 904 }
 905
 906 static void ip6_link_failure(struct sk_buff *skb)
 907 {
 908         struct rt6_info *rt;
 909
 910         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
 911
 912         rt = (struct rt6_info *) skb_dst(skb);
 913         if (rt) {
 914                 if (rt->rt6i_flags&RTF_CACHE) {
 915                         dst_set_expires(&rt->u.dst, 0);
 916                         rt->rt6i_flags |= RTF_EXPIRES;
 917                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
 918                         rt->rt6i_node->fn_sernum = -1;
 919         }
 920 }
 921
 922 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
 923 {
 924         struct rt6_info *rt6 = (struct rt6_info*)dst;
 925
 926         if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
 927                 rt6->rt6i_flags |= RTF_MODIFIED;
 928                 if (mtu < IPV6_MIN_MTU) {
 929                         mtu = IPV6_MIN_MTU;
 930                         dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
 931                 }
 932                 dst->metrics[RTAX_MTU-1] = mtu;
 933                 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
 934         }
 935 }
 936
 937 static int ipv6_get_mtu(struct net_device *dev);
 938
 939 static inline unsigned int ipv6_advmss(struct net *net, unsigned int mtu)
 940 {
 941         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
 942
 943         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
 944                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
 945
 946         /*
 947          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
 948          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
 949          * IPV6_MAXPLEN is also valid and means: "any MSS,
 950          * rely only on pmtu discovery"
 951          */
 952         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
 953                 mtu = IPV6_MAXPLEN;
 954         return mtu;
 955 }
 956
 957 static struct dst_entry *icmp6_dst_gc_list;
 958 static DEFINE_SPINLOCK(icmp6_dst_lock);
 959
 960 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
 961                                   struct neighbour *neigh,
 962                                   const struct in6_addr *addr)
 963 {
 964         struct rt6_info *rt;
 965         struct inet6_dev *idev = in6_dev_get(dev);
 966         struct net *net = dev_net(dev);
 967
 968         if (unlikely(idev == NULL))
 969                 return NULL;
 970
 971         rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
 972         if (unlikely(rt == NULL)) {
 973                 in6_dev_put(idev);
 974                 goto out;
 975         }
 976
 977         dev_hold(dev);
 978         if (neigh)
 979                 neigh_hold(neigh);
 980         else {
 981                 neigh = ndisc_get_neigh(dev, addr);
 982                 if (IS_ERR(neigh))
 983                         neigh = NULL;
 984         }
 985
 986         rt->rt6i_dev      = dev;
 987         rt->rt6i_idev     = idev;
 988         rt->rt6i_nexthop  = neigh;
 989         atomic_set(&rt->u.dst.__refcnt, 1);
 990         rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
 991         rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
 992         rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
 993         rt->u.dst.output  = ip6_output;
 994
 995 #if 0   /* there's no chance to use these for ndisc */
 996         rt->u.dst.flags   = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
 997                                 ? DST_HOST
 998                                 : 0;
 999         ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1000         rt->rt6i_dst.plen = 128;
1001 #endif
1002
1003         spin_lock_bh(&icmp6_dst_lock);
1004         rt->u.dst.next = icmp6_dst_gc_list;
1005         icmp6_dst_gc_list = &rt->u.dst;
1006         spin_unlock_bh(&icmp6_dst_lock);
1007
1008         fib6_force_start_gc(net);
1009
1010 out:
1011         return &rt->u.dst;
1012 }
1013
1014 int icmp6_dst_gc(void)
1015 {
1016         struct dst_entry *dst, *next, **pprev;
1017         int more = 0;
1018
1019         next = NULL;
1020
1021         spin_lock_bh(&icmp6_dst_lock);
1022         pprev = &icmp6_dst_gc_list;
1023
1024         while ((dst = *pprev) != NULL) {
1025                 if (!atomic_read(&dst->__refcnt)) {
1026                         *pprev = dst->next;
1027                         dst_free(dst);
1028                 } else {
1029                         pprev = &dst->next;
1030                         ++more;
1031                 }
1032         }
1033
1034         spin_unlock_bh(&icmp6_dst_lock);
1035
1036         return more;
1037 }
1038
1039 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1040                             void *arg)
1041 {
1042         struct dst_entry *dst, **pprev;
1043
1044         spin_lock_bh(&icmp6_dst_lock);
1045         pprev = &icmp6_dst_gc_list;
1046         while ((dst = *pprev) != NULL) {
1047                 struct rt6_info *rt = (struct rt6_info *) dst;
1048                 if (func(rt, arg)) {
1049                         *pprev = dst->next;
1050                         dst_free(dst);
1051                 } else {
1052                         pprev = &dst->next;
1053                 }
1054         }
1055         spin_unlock_bh(&icmp6_dst_lock);
1056 }
1057
1058 static int ip6_dst_gc(struct dst_ops *ops)
1059 {
1060         unsigned long now = jiffies;
1061         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1062         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1063         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1064         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1065         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1066         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1067
1068         if (time_after(rt_last_gc + rt_min_interval, now) &&
1069             atomic_read(&ops->entries) <= rt_max_size)
1070                 goto out;
1071
1072         net->ipv6.ip6_rt_gc_expire++;
1073         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
1074         net->ipv6.ip6_rt_last_gc = now;
1075         if (atomic_read(&ops->entries) < ops->gc_thresh)
1076                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1077 out:
1078         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1079         return (atomic_read(&ops->entries) > rt_max_size);
1080 }
1081
1082 /* Clean host part of a prefix. Not necessary in radix tree,
1083    but results in cleaner routing tables.
1084
1085    Remove it only when all the things will work!
1086  */
1087
1088 static int ipv6_get_mtu(struct net_device *dev)
1089 {
1090         int mtu = IPV6_MIN_MTU;
1091         struct inet6_dev *idev;
1092
1093         idev = in6_dev_get(dev);
1094         if (idev) {
1095                 mtu = idev->cnf.mtu6;
1096                 in6_dev_put(idev);
1097         }
1098         return mtu;
1099 }
1100
1101 int ip6_dst_hoplimit(struct dst_entry *dst)
1102 {
1103         int hoplimit = dst_metric(dst, RTAX_HOPLIMIT);
1104         if (hoplimit < 0) {
1105                 struct net_device *dev = dst->dev;
1106                 struct inet6_dev *idev = in6_dev_get(dev);
1107                 if (idev) {
1108                         hoplimit = idev->cnf.hop_limit;
1109                         in6_dev_put(idev);
1110                 } else
1111                         hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1112         }
1113         return hoplimit;
1114 }
1115
1116 /*
1117  *
1118  */
1119
1120 int ip6_route_add(struct fib6_config *cfg)
1121 {
1122         int err;
1123         struct net *net = cfg->fc_nlinfo.nl_net;
1124         struct rt6_info *rt = NULL;
1125         struct net_device *dev = NULL;
1126         struct inet6_dev *idev = NULL;
1127         struct fib6_table *table;
1128         int addr_type;
1129
1130         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1131                 return -EINVAL;
1132 #ifndef CONFIG_IPV6_SUBTREES
1133         if (cfg->fc_src_len)
1134                 return -EINVAL;
1135 #endif
1136         if (cfg->fc_ifindex) {
1137                 err = -ENODEV;
1138                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1139                 if (!dev)
1140                         goto out;
1141                 idev = in6_dev_get(dev);
1142                 if (!idev)
1143                         goto out;
1144         }
1145
1146         if (cfg->fc_metric == 0)
1147                 cfg->fc_metric = IP6_RT_PRIO_USER;
1148
1149         table = fib6_new_table(net, cfg->fc_table);
1150         if (table == NULL) {
1151                 err = -ENOBUFS;
1152                 goto out;
1153         }
1154
1155         rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1156
1157         if (rt == NULL) {
1158                 err = -ENOMEM;
1159                 goto out;
1160         }
1161
1162         rt->u.dst.obsolete = -1;
1163         rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ?
1164                                 jiffies + clock_t_to_jiffies(cfg->fc_expires) :
1165                                 0;
1166
1167         if (cfg->fc_protocol == RTPROT_UNSPEC)
1168                 cfg->fc_protocol = RTPROT_BOOT;
1169         rt->rt6i_protocol = cfg->fc_protocol;
1170
1171         addr_type = ipv6_addr_type(&cfg->fc_dst);
1172
1173         if (addr_type & IPV6_ADDR_MULTICAST)
1174                 rt->u.dst.input = ip6_mc_input;
1175         else
1176                 rt->u.dst.input = ip6_forward;
1177
1178         rt->u.dst.output = ip6_output;
1179
1180         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1181         rt->rt6i_dst.plen = cfg->fc_dst_len;
1182         if (rt->rt6i_dst.plen == 128)
1183                rt->u.dst.flags = DST_HOST;
1184
1185 #ifdef CONFIG_IPV6_SUBTREES
1186         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1187         rt->rt6i_src.plen = cfg->fc_src_len;
1188 #endif
1189
1190         rt->rt6i_metric = cfg->fc_metric;
1191
1192         /* We cannot add true routes via loopback here,
1193            they would result in kernel looping; promote them to reject routes
1194          */
1195         if ((cfg->fc_flags & RTF_REJECT) ||
1196             (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1197                 /* hold loopback dev/idev if we haven't done so. */
1198                 if (dev != net->loopback_dev) {
1199                         if (dev) {
1200                                 dev_put(dev);
1201                                 in6_dev_put(idev);
1202                         }
1203                         dev = net->loopback_dev;
1204                         dev_hold(dev);
1205                         idev = in6_dev_get(dev);
1206                         if (!idev) {
1207                                 err = -ENODEV;
1208                                 goto out;
1209                         }
1210                 }
1211                 rt->u.dst.output = ip6_pkt_discard_out;
1212                 rt->u.dst.input = ip6_pkt_discard;
1213                 rt->u.dst.error = -ENETUNREACH;
1214                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1215                 goto install_route;
1216         }
1217
1218         if (cfg->fc_flags & RTF_GATEWAY) {
1219                 struct in6_addr *gw_addr;
1220                 int gwa_type;
1221
1222                 gw_addr = &cfg->fc_gateway;
1223                 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1224                 gwa_type = ipv6_addr_type(gw_addr);
1225
1226                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1227                         struct rt6_info *grt;
1228
1229                         /* IPv6 strictly inhibits using not link-local
1230                            addresses as nexthop address.
1231                            Otherwise, router will not able to send redirects.
1232                            It is very good, but in some (rare!) circumstances
1233                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1234                            some exceptions. --ANK
1235                          */
1236                         err = -EINVAL;
1237                         if (!(gwa_type&IPV6_ADDR_UNICAST))
1238                                 goto out;
1239
1240                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1241
1242                         err = -EHOSTUNREACH;
1243                         if (grt == NULL)
1244                                 goto out;
1245                         if (dev) {
1246                                 if (dev != grt->rt6i_dev) {
1247                                         dst_release(&grt->u.dst);
1248                                         goto out;
1249                                 }
1250                         } else {
1251                                 dev = grt->rt6i_dev;
1252                                 idev = grt->rt6i_idev;
1253                                 dev_hold(dev);
1254                                 in6_dev_hold(grt->rt6i_idev);
1255                         }
1256                         if (!(grt->rt6i_flags&RTF_GATEWAY))
1257                                 err = 0;
1258                         dst_release(&grt->u.dst);
1259
1260                         if (err)
1261                                 goto out;
1262                 }
1263                 err = -EINVAL;
1264                 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1265                         goto out;
1266         }
1267
1268         err = -ENODEV;
1269         if (dev == NULL)
1270                 goto out;
1271
1272         if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1273                 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1274                 if (IS_ERR(rt->rt6i_nexthop)) {
1275                         err = PTR_ERR(rt->rt6i_nexthop);
1276                         rt->rt6i_nexthop = NULL;
1277                         goto out;
1278                 }
1279         }
1280
1281         rt->rt6i_flags = cfg->fc_flags;
1282
1283 install_route:
1284         if (cfg->fc_mx) {
1285                 struct nlattr *nla;
1286                 int remaining;
1287
1288                 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1289                         int type = nla_type(nla);
1290
1291                         if (type) {
1292                                 if (type > RTAX_MAX) {
1293                                         err = -EINVAL;
1294                                         goto out;
1295                                 }
1296
1297                                 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1298                         }
1299                 }
1300         }
1301
1302         if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0)
1303                 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1304         if (!dst_mtu(&rt->u.dst))
1305                 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1306         if (!dst_metric(&rt->u.dst, RTAX_ADVMSS))
1307                 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
1308         rt->u.dst.dev = dev;
1309         rt->rt6i_idev = idev;
1310         rt->rt6i_table = table;
1311
1312         cfg->fc_nlinfo.nl_net = dev_net(dev);
1313
1314         return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1315
1316 out:
1317         if (dev)
1318                 dev_put(dev);
1319         if (idev)
1320                 in6_dev_put(idev);
1321         if (rt)
1322                 dst_free(&rt->u.dst);
1323         return err;
1324 }
1325
1326 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1327 {
1328         int err;
1329         struct fib6_table *table;
1330         struct net *net = dev_net(rt->rt6i_dev);
1331
1332         if (rt == net->ipv6.ip6_null_entry)
1333                 return -ENOENT;
1334
1335         table = rt->rt6i_table;
1336         write_lock_bh(&table->tb6_lock);
1337
1338         err = fib6_del(rt, info);
1339         dst_release(&rt->u.dst);
1340
1341         write_unlock_bh(&table->tb6_lock);
1342
1343         return err;
1344 }
1345
1346 int ip6_del_rt(struct rt6_info *rt)
1347 {
1348         struct nl_info info = {
1349                 .nl_net = dev_net(rt->rt6i_dev),
1350         };
1351         return __ip6_del_rt(rt, &info);
1352 }
1353
1354 static int ip6_route_del(struct fib6_config *cfg)
1355 {
1356         struct fib6_table *table;
1357         struct fib6_node *fn;
1358         struct rt6_info *rt;
1359         int err = -ESRCH;
1360
1361         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1362         if (table == NULL)
1363                 return err;
1364
1365         read_lock_bh(&table->tb6_lock);
1366
1367         fn = fib6_locate(&table->tb6_root,
1368                          &cfg->fc_dst, cfg->fc_dst_len,
1369                          &cfg->fc_src, cfg->fc_src_len);
1370
1371         if (fn) {
1372                 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1373                         if (cfg->fc_ifindex &&
1374                             (rt->rt6i_dev == NULL ||
1375                              rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1376                                 continue;
1377                         if (cfg->fc_flags & RTF_GATEWAY &&
1378                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1379                                 continue;
1380                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1381                                 continue;
1382                         dst_hold(&rt->u.dst);
1383                         read_unlock_bh(&table->tb6_lock);
1384
1385                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1386                 }
1387         }
1388         read_unlock_bh(&table->tb6_lock);
1389
1390         return err;
1391 }
1392
1393 /*
1394  *      Handle redirects
1395  */
1396 struct ip6rd_flowi {
1397         struct flowi fl;
1398         struct in6_addr gateway;
1399 };
1400
1401 static struct rt6_info *__ip6_route_redirect(struct net *net,
1402                                              struct fib6_table *table,
1403                                              struct flowi *fl,
1404                                              int flags)
1405 {
1406         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1407         struct rt6_info *rt;
1408         struct fib6_node *fn;
1409
1410         /*
1411          * Get the "current" route for this destination and
1412          * check if the redirect has come from approriate router.
1413          *
1414          * RFC 2461 specifies that redirects should only be
1415          * accepted if they come from the nexthop to the target.
1416          * Due to the way the routes are chosen, this notion
1417          * is a bit fuzzy and one might need to check all possible
1418          * routes.
1419          */
1420
1421         read_lock_bh(&table->tb6_lock);
1422         fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1423 restart:
1424         for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1425                 /*
1426                  * Current route is on-link; redirect is always invalid.
1427                  *
1428                  * Seems, previous statement is not true. It could
1429                  * be node, which looks for us as on-link (f.e. proxy ndisc)
1430                  * But then router serving it might decide, that we should
1431                  * know truth 8)8) --ANK (980726).
1432                  */
1433                 if (rt6_check_expired(rt))
1434                         continue;
1435                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1436                         continue;
1437                 if (fl->oif != rt->rt6i_dev->ifindex)
1438                         continue;
1439                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1440                         continue;
1441                 break;
1442         }
1443
1444         if (!rt)
1445                 rt = net->ipv6.ip6_null_entry;
1446         BACKTRACK(net, &fl->fl6_src);
1447 out:
1448         dst_hold(&rt->u.dst);
1449
1450         read_unlock_bh(&table->tb6_lock);
1451
1452         return rt;
1453 };
1454
1455 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1456                                            struct in6_addr *src,
1457                                            struct in6_addr *gateway,
1458                                            struct net_device *dev)
1459 {
1460         int flags = RT6_LOOKUP_F_HAS_SADDR;
1461         struct net *net = dev_net(dev);
1462         struct ip6rd_flowi rdfl = {
1463                 .fl = {
1464                         .oif = dev->ifindex,
1465                         .nl_u = {
1466                                 .ip6_u = {
1467                                         .daddr = *dest,
1468                                         .saddr = *src,
1469                                 },
1470                         },
1471                 },
1472         };
1473
1474         ipv6_addr_copy(&rdfl.gateway, gateway);
1475
1476         if (rt6_need_strict(dest))
1477                 flags |= RT6_LOOKUP_F_IFACE;
1478
1479         return (struct rt6_info *)fib6_rule_lookup(net, (struct flowi *)&rdfl,
1480                                                    flags, __ip6_route_redirect);
1481 }
1482
1483 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1484                   struct in6_addr *saddr,
1485                   struct neighbour *neigh, u8 *lladdr, int on_link)
1486 {
1487         struct rt6_info *rt, *nrt = NULL;
1488         struct netevent_redirect netevent;
1489         struct net *net = dev_net(neigh->dev);
1490
1491         rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1492
1493         if (rt == net->ipv6.ip6_null_entry) {
1494                 if (net_ratelimit())
1495                         printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1496                                "for redirect target\n");
1497                 goto out;
1498         }
1499
1500         /*
1501          *      We have finally decided to accept it.
1502          */
1503
1504         neigh_update(neigh, lladdr, NUD_STALE,
1505                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
1506                      NEIGH_UPDATE_F_OVERRIDE|
1507                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1508                                      NEIGH_UPDATE_F_ISROUTER))
1509                      );
1510
1511         /*
1512          * Redirect received -> path was valid.
1513          * Look, redirects are sent only in response to data packets,
1514          * so that this nexthop apparently is reachable. --ANK
1515          */
1516         dst_confirm(&rt->u.dst);
1517
1518         /* Duplicate redirect: silently ignore. */
1519         if (neigh == rt->u.dst.neighbour)
1520                 goto out;
1521
1522         nrt = ip6_rt_copy(rt);
1523         if (nrt == NULL)
1524                 goto out;
1525
1526         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1527         if (on_link)
1528                 nrt->rt6i_flags &= ~RTF_GATEWAY;
1529
1530         ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1531         nrt->rt6i_dst.plen = 128;
1532         nrt->u.dst.flags |= DST_HOST;
1533
1534         ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1535         nrt->rt6i_nexthop = neigh_clone(neigh);
1536         /* Reset pmtu, it may be better */
1537         nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1538         nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dev_net(neigh->dev),
1539                                                         dst_mtu(&nrt->u.dst));
1540
1541         if (ip6_ins_rt(nrt))
1542                 goto out;
1543
1544         netevent.old = &rt->u.dst;
1545         netevent.new = &nrt->u.dst;
1546         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1547
1548         if (rt->rt6i_flags&RTF_CACHE) {
1549                 ip6_del_rt(rt);
1550                 return;
1551         }
1552
1553 out:
1554         dst_release(&rt->u.dst);
1555 }
1556
1557 /*
1558  *      Handle ICMP "packet too big" messages
1559  *      i.e. Path MTU discovery
1560  */
1561
1562 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1563                         struct net_device *dev, u32 pmtu)
1564 {
1565         struct rt6_info *rt, *nrt;
1566         struct net *net = dev_net(dev);
1567         int allfrag = 0;
1568
1569         rt = rt6_lookup(net, daddr, saddr, dev->ifindex, 0);
1570         if (rt == NULL)
1571                 return;
1572
1573         if (pmtu >= dst_mtu(&rt->u.dst))
1574                 goto out;
1575
1576         if (pmtu < IPV6_MIN_MTU) {
1577                 /*
1578                  * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1579                  * MTU (1280) and a fragment header should always be included
1580                  * after a node receiving Too Big message reporting PMTU is
1581                  * less than the IPv6 Minimum Link MTU.
1582                  */
1583                 pmtu = IPV6_MIN_MTU;
1584                 allfrag = 1;
1585         }
1586
1587         /* New mtu received -> path was valid.
1588            They are sent only in response to data packets,
1589            so that this nexthop apparently is reachable. --ANK
1590          */
1591         dst_confirm(&rt->u.dst);
1592
1593         /* Host route. If it is static, it would be better
1594            not to override it, but add new one, so that
1595            when cache entry will expire old pmtu
1596            would return automatically.
1597          */
1598         if (rt->rt6i_flags & RTF_CACHE) {
1599                 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1600                 if (allfrag)
1601                         rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1602                 dst_set_expires(&rt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1603                 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1604                 goto out;
1605         }
1606
1607         /* Network route.
1608            Two cases are possible:
1609            1. It is connected route. Action: COW
1610            2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1611          */
1612         if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1613                 nrt = rt6_alloc_cow(rt, daddr, saddr);
1614         else
1615                 nrt = rt6_alloc_clone(rt, daddr);
1616
1617         if (nrt) {
1618                 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1619                 if (allfrag)
1620                         nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1621
1622                 /* According to RFC 1981, detecting PMTU increase shouldn't be
1623                  * happened within 5 mins, the recommended timer is 10 mins.
1624                  * Here this route expiration time is set to ip6_rt_mtu_expires
1625                  * which is 10 mins. After 10 mins the decreased pmtu is expired
1626                  * and detecting PMTU increase will be automatically happened.
1627                  */
1628                 dst_set_expires(&nrt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1629                 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1630
1631                 ip6_ins_rt(nrt);
1632         }
1633 out:
1634         dst_release(&rt->u.dst);
1635 }
1636
1637 /*
1638  *      Misc support functions
1639  */
1640
1641 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1642 {
1643         struct net *net = dev_net(ort->rt6i_dev);
1644         struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1645
1646         if (rt) {
1647                 rt->u.dst.input = ort->u.dst.input;
1648                 rt->u.dst.output = ort->u.dst.output;
1649
1650                 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1651                 rt->u.dst.error = ort->u.dst.error;
1652                 rt->u.dst.dev = ort->u.dst.dev;
1653                 if (rt->u.dst.dev)
1654                         dev_hold(rt->u.dst.dev);
1655                 rt->rt6i_idev = ort->rt6i_idev;
1656                 if (rt->rt6i_idev)
1657                         in6_dev_hold(rt->rt6i_idev);
1658                 rt->u.dst.lastuse = jiffies;
1659                 rt->rt6i_expires = 0;
1660
1661                 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1662                 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1663                 rt->rt6i_metric = 0;
1664
1665                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1666 #ifdef CONFIG_IPV6_SUBTREES
1667                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1668 #endif
1669                 rt->rt6i_table = ort->rt6i_table;
1670         }
1671         return rt;
1672 }
1673
1674 #ifdef CONFIG_IPV6_ROUTE_INFO
1675 static struct rt6_info *rt6_get_route_info(struct net *net,
1676                                            struct in6_addr *prefix, int prefixlen,
1677                                            struct in6_addr *gwaddr, int ifindex)
1678 {
1679         struct fib6_node *fn;
1680         struct rt6_info *rt = NULL;
1681         struct fib6_table *table;
1682
1683         table = fib6_get_table(net, RT6_TABLE_INFO);
1684         if (table == NULL)
1685                 return NULL;
1686
1687         write_lock_bh(&table->tb6_lock);
1688         fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1689         if (!fn)
1690                 goto out;
1691
1692         for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1693                 if (rt->rt6i_dev->ifindex != ifindex)
1694                         continue;
1695                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1696                         continue;
1697                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1698                         continue;
1699                 dst_hold(&rt->u.dst);
1700                 break;
1701         }
1702 out:
1703         write_unlock_bh(&table->tb6_lock);
1704         return rt;
1705 }
1706
1707 static struct rt6_info *rt6_add_route_info(struct net *net,
1708                                            struct in6_addr *prefix, int prefixlen,
1709                                            struct in6_addr *gwaddr, int ifindex,
1710                                            unsigned pref)
1711 {
1712         struct fib6_config cfg = {
1713                 .fc_table       = RT6_TABLE_INFO,
1714                 .fc_metric      = IP6_RT_PRIO_USER,
1715                 .fc_ifindex     = ifindex,
1716                 .fc_dst_len     = prefixlen,
1717                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1718                                   RTF_UP | RTF_PREF(pref),
1719                 .fc_nlinfo.pid = 0,
1720                 .fc_nlinfo.nlh = NULL,
1721                 .fc_nlinfo.nl_net = net,
1722         };
1723
1724         ipv6_addr_copy(&cfg.fc_dst, prefix);
1725         ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1726
1727         /* We should treat it as a default route if prefix length is 0. */
1728         if (!prefixlen)
1729                 cfg.fc_flags |= RTF_DEFAULT;
1730
1731         ip6_route_add(&cfg);
1732
1733         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1734 }
1735 #endif
1736
1737 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1738 {
1739         struct rt6_info *rt;
1740         struct fib6_table *table;
1741
1742         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1743         if (table == NULL)
1744                 return NULL;
1745
1746         write_lock_bh(&table->tb6_lock);
1747         for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
1748                 if (dev == rt->rt6i_dev &&
1749                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1750                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
1751                         break;
1752         }
1753         if (rt)
1754                 dst_hold(&rt->u.dst);
1755         write_unlock_bh(&table->tb6_lock);
1756         return rt;
1757 }
1758
1759 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1760                                      struct net_device *dev,
1761                                      unsigned int pref)
1762 {
1763         struct fib6_config cfg = {
1764                 .fc_table       = RT6_TABLE_DFLT,
1765                 .fc_metric      = IP6_RT_PRIO_USER,
1766                 .fc_ifindex     = dev->ifindex,
1767                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1768                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1769                 .fc_nlinfo.pid = 0,
1770                 .fc_nlinfo.nlh = NULL,
1771                 .fc_nlinfo.nl_net = dev_net(dev),
1772         };
1773
1774         ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1775
1776         ip6_route_add(&cfg);
1777
1778         return rt6_get_dflt_router(gwaddr, dev);
1779 }
1780
1781 void rt6_purge_dflt_routers(struct net *net)
1782 {
1783         struct rt6_info *rt;
1784         struct fib6_table *table;
1785
1786         /* NOTE: Keep consistent with rt6_get_dflt_router */
1787         table = fib6_get_table(net, RT6_TABLE_DFLT);
1788         if (table == NULL)
1789                 return;
1790
1791 restart:
1792         read_lock_bh(&table->tb6_lock);
1793         for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
1794                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1795                         dst_hold(&rt->u.dst);
1796                         read_unlock_bh(&table->tb6_lock);
1797                         ip6_del_rt(rt);
1798                         goto restart;
1799                 }
1800         }
1801         read_unlock_bh(&table->tb6_lock);
1802 }
1803
1804 static void rtmsg_to_fib6_config(struct net *net,
1805                                  struct in6_rtmsg *rtmsg,
1806                                  struct fib6_config *cfg)
1807 {
1808         memset(cfg, 0, sizeof(*cfg));
1809
1810         cfg->fc_table = RT6_TABLE_MAIN;
1811         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1812         cfg->fc_metric = rtmsg->rtmsg_metric;
1813         cfg->fc_expires = rtmsg->rtmsg_info;
1814         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1815         cfg->fc_src_len = rtmsg->rtmsg_src_len;
1816         cfg->fc_flags = rtmsg->rtmsg_flags;
1817
1818         cfg->fc_nlinfo.nl_net = net;
1819
1820         ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1821         ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1822         ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1823 }
1824
1825 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
1826 {
1827         struct fib6_config cfg;
1828         struct in6_rtmsg rtmsg;
1829         int err;
1830
1831         switch(cmd) {
1832         case SIOCADDRT:         /* Add a route */
1833         case SIOCDELRT:         /* Delete a route */
1834                 if (!capable(CAP_NET_ADMIN))
1835                         return -EPERM;
1836                 err = copy_from_user(&rtmsg, arg,
1837                                      sizeof(struct in6_rtmsg));
1838                 if (err)
1839                         return -EFAULT;
1840
1841                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1842
1843                 rtnl_lock();
1844                 switch (cmd) {
1845                 case SIOCADDRT:
1846                         err = ip6_route_add(&cfg);
1847                         break;
1848                 case SIOCDELRT:
1849                         err = ip6_route_del(&cfg);
1850                         break;
1851                 default:
1852                         err = -EINVAL;
1853                 }
1854                 rtnl_unlock();
1855
1856                 return err;
1857         }
1858
1859         return -EINVAL;
1860 }
1861
1862 /*
1863  *      Drop the packet on the floor
1864  */
1865
1866 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
1867 {
1868         int type;
1869         struct dst_entry *dst = skb_dst(skb);
1870         switch (ipstats_mib_noroutes) {
1871         case IPSTATS_MIB_INNOROUTES:
1872                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1873                 if (type == IPV6_ADDR_ANY) {
1874                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
1875                                       IPSTATS_MIB_INADDRERRORS);
1876                         break;
1877                 }
1878                 /* FALLTHROUGH */
1879         case IPSTATS_MIB_OUTNOROUTES:
1880                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
1881                               ipstats_mib_noroutes);
1882                 break;
1883         }
1884         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
1885         kfree_skb(skb);
1886         return 0;
1887 }
1888
1889 static int ip6_pkt_discard(struct sk_buff *skb)
1890 {
1891         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1892 }
1893
1894 static int ip6_pkt_discard_out(struct sk_buff *skb)
1895 {
1896         skb->dev = skb_dst(skb)->dev;
1897         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1898 }
1899
1900 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1901
1902 static int ip6_pkt_prohibit(struct sk_buff *skb)
1903 {
1904         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1905 }
1906
1907 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1908 {
1909         skb->dev = skb_dst(skb)->dev;
1910         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1911 }
1912
1913 #endif
1914
1915 /*
1916  *      Allocate a dst for local (unicast / anycast) address.
1917  */
1918
1919 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1920                                     const struct in6_addr *addr,
1921                                     int anycast)
1922 {
1923         struct net *net = dev_net(idev->dev);
1924         struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1925         struct neighbour *neigh;
1926
1927         if (rt == NULL)
1928                 return ERR_PTR(-ENOMEM);
1929
1930         dev_hold(net->loopback_dev);
1931         in6_dev_hold(idev);
1932
1933         rt->u.dst.flags = DST_HOST;
1934         rt->u.dst.input = ip6_input;
1935         rt->u.dst.output = ip6_output;
1936         rt->rt6i_dev = net->loopback_dev;
1937         rt->rt6i_idev = idev;
1938         rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1939         rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
1940         rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1941         rt->u.dst.obsolete = -1;
1942
1943         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1944         if (anycast)
1945                 rt->rt6i_flags |= RTF_ANYCAST;
1946         else
1947                 rt->rt6i_flags |= RTF_LOCAL;
1948         neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1949         if (IS_ERR(neigh)) {
1950                 dst_free(&rt->u.dst);
1951
1952                 /* We are casting this because that is the return
1953                  * value type.  But an errno encoded pointer is the
1954                  * same regardless of the underlying pointer type,
1955                  * and that's what we are returning.  So this is OK.
1956                  */
1957                 return (struct rt6_info *) neigh;
1958         }
1959         rt->rt6i_nexthop = neigh;
1960
1961         ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1962         rt->rt6i_dst.plen = 128;
1963         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
1964
1965         atomic_set(&rt->u.dst.__refcnt, 1);
1966
1967         return rt;
1968 }
1969
1970 struct arg_dev_net {
1971         struct net_device *dev;
1972         struct net *net;
1973 };
1974
1975 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1976 {
1977         struct net_device *dev = ((struct arg_dev_net *)arg)->dev;
1978         struct net *net = ((struct arg_dev_net *)arg)->net;
1979
1980         if (((void *)rt->rt6i_dev == dev || dev == NULL) &&
1981             rt != net->ipv6.ip6_null_entry) {
1982                 RT6_TRACE("deleted by ifdown %p\n", rt);
1983                 return -1;
1984         }
1985         return 0;
1986 }
1987
1988 void rt6_ifdown(struct net *net, struct net_device *dev)
1989 {
1990         struct arg_dev_net adn = {
1991                 .dev = dev,
1992                 .net = net,
1993         };
1994
1995         fib6_clean_all(net, fib6_ifdown, 0, &adn);
1996         icmp6_clean_all(fib6_ifdown, &adn);
1997 }
1998
1999 struct rt6_mtu_change_arg
2000 {
2001         struct net_device *dev;
2002         unsigned mtu;
2003 };
2004
2005 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2006 {
2007         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2008         struct inet6_dev *idev;
2009         struct net *net = dev_net(arg->dev);
2010
2011         /* In IPv6 pmtu discovery is not optional,
2012            so that RTAX_MTU lock cannot disable it.
2013            We still use this lock to block changes
2014            caused by addrconf/ndisc.
2015         */
2016
2017         idev = __in6_dev_get(arg->dev);
2018         if (idev == NULL)
2019                 return 0;
2020
2021         /* For administrative MTU increase, there is no way to discover
2022            IPv6 PMTU increase, so PMTU increase should be updated here.
2023            Since RFC 1981 doesn't include administrative MTU increase
2024            update PMTU increase is a MUST. (i.e. jumbo frame)
2025          */
2026         /*
2027            If new MTU is less than route PMTU, this new MTU will be the
2028            lowest MTU in the path, update the route PMTU to reflect PMTU
2029            decreases; if new MTU is greater than route PMTU, and the
2030            old MTU is the lowest MTU in the path, update the route PMTU
2031            to reflect the increase. In this case if the other nodes' MTU
2032            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2033            PMTU discouvery.
2034          */
2035         if (rt->rt6i_dev == arg->dev &&
2036             !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
2037             (dst_mtu(&rt->u.dst) >= arg->mtu ||
2038              (dst_mtu(&rt->u.dst) < arg->mtu &&
2039               dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) {
2040                 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
2041                 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, arg->mtu);
2042         }
2043         return 0;
2044 }
2045
2046 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
2047 {
2048         struct rt6_mtu_change_arg arg = {
2049                 .dev = dev,
2050                 .mtu = mtu,
2051         };
2052
2053         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
2054 }
2055
2056 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2057         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2058         [RTA_OIF]               = { .type = NLA_U32 },
2059         [RTA_IIF]               = { .type = NLA_U32 },
2060         [RTA_PRIORITY]          = { .type = NLA_U32 },
2061         [RTA_METRICS]           = { .type = NLA_NESTED },
2062 };
2063
2064 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2065                               struct fib6_config *cfg)
2066 {
2067         struct rtmsg *rtm;
2068         struct nlattr *tb[RTA_MAX+1];
2069         int err;
2070
2071         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2072         if (err < 0)
2073                 goto errout;
2074
2075         err = -EINVAL;
2076         rtm = nlmsg_data(nlh);
2077         memset(cfg, 0, sizeof(*cfg));
2078
2079         cfg->fc_table = rtm->rtm_table;
2080         cfg->fc_dst_len = rtm->rtm_dst_len;
2081         cfg->fc_src_len = rtm->rtm_src_len;
2082         cfg->fc_flags = RTF_UP;
2083         cfg->fc_protocol = rtm->rtm_protocol;
2084
2085         if (rtm->rtm_type == RTN_UNREACHABLE)
2086                 cfg->fc_flags |= RTF_REJECT;
2087
2088         cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2089         cfg->fc_nlinfo.nlh = nlh;
2090         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2091
2092         if (tb[RTA_GATEWAY]) {
2093                 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2094                 cfg->fc_flags |= RTF_GATEWAY;
2095         }
2096
2097         if (tb[RTA_DST]) {
2098                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2099
2100                 if (nla_len(tb[RTA_DST]) < plen)
2101                         goto errout;
2102
2103                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2104         }
2105
2106         if (tb[RTA_SRC]) {
2107                 int plen = (rtm->rtm_src_len + 7) >> 3;
2108
2109                 if (nla_len(tb[RTA_SRC]) < plen)
2110                         goto errout;
2111
2112                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2113         }
2114
2115         if (tb[RTA_OIF])
2116                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2117
2118         if (tb[RTA_PRIORITY])
2119                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2120
2121         if (tb[RTA_METRICS]) {
2122                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2123                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2124         }
2125
2126         if (tb[RTA_TABLE])
2127                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2128
2129         err = 0;
2130 errout:
2131         return err;
2132 }
2133
2134 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2135 {
2136         struct fib6_config cfg;
2137         int err;
2138
2139         err = rtm_to_fib6_config(skb, nlh, &cfg);
2140         if (err < 0)
2141                 return err;
2142
2143         return ip6_route_del(&cfg);
2144 }
2145
2146 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2147 {
2148         struct fib6_config cfg;
2149         int err;
2150
2151         err = rtm_to_fib6_config(skb, nlh, &cfg);
2152         if (err < 0)
2153                 return err;
2154
2155         return ip6_route_add(&cfg);
2156 }
2157
2158 static inline size_t rt6_nlmsg_size(void)
2159 {
2160         return NLMSG_ALIGN(sizeof(struct rtmsg))
2161                + nla_total_size(16) /* RTA_SRC */
2162                + nla_total_size(16) /* RTA_DST */
2163                + nla_total_size(16) /* RTA_GATEWAY */
2164                + nla_total_size(16) /* RTA_PREFSRC */
2165                + nla_total_size(4) /* RTA_TABLE */
2166                + nla_total_size(4) /* RTA_IIF */
2167                + nla_total_size(4) /* RTA_OIF */
2168                + nla_total_size(4) /* RTA_PRIORITY */
2169                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2170                + nla_total_size(sizeof(struct rta_cacheinfo));
2171 }
2172
2173 static int rt6_fill_node(struct net *net,
2174                          struct sk_buff *skb, struct rt6_info *rt,
2175                          struct in6_addr *dst, struct in6_addr *src,
2176                          int iif, int type, u32 pid, u32 seq,
2177                          int prefix, int nowait, unsigned int flags)
2178 {
2179         struct rtmsg *rtm;
2180         struct nlmsghdr *nlh;
2181         long expires;
2182         u32 table;
2183
2184         if (prefix) {   /* user wants prefix routes only */
2185                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2186                         /* success since this is not a prefix route */
2187                         return 1;
2188                 }
2189         }
2190
2191         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2192         if (nlh == NULL)
2193                 return -EMSGSIZE;
2194
2195         rtm = nlmsg_data(nlh);
2196         rtm->rtm_family = AF_INET6;
2197         rtm->rtm_dst_len = rt->rt6i_dst.plen;
2198         rtm->rtm_src_len = rt->rt6i_src.plen;
2199         rtm->rtm_tos = 0;
2200         if (rt->rt6i_table)
2201                 table = rt->rt6i_table->tb6_id;
2202         else
2203                 table = RT6_TABLE_UNSPEC;
2204         rtm->rtm_table = table;
2205         NLA_PUT_U32(skb, RTA_TABLE, table);
2206         if (rt->rt6i_flags&RTF_REJECT)
2207                 rtm->rtm_type = RTN_UNREACHABLE;
2208         else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2209                 rtm->rtm_type = RTN_LOCAL;
2210         else
2211                 rtm->rtm_type = RTN_UNICAST;
2212         rtm->rtm_flags = 0;
2213         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2214         rtm->rtm_protocol = rt->rt6i_protocol;
2215         if (rt->rt6i_flags&RTF_DYNAMIC)
2216                 rtm->rtm_protocol = RTPROT_REDIRECT;
2217         else if (rt->rt6i_flags & RTF_ADDRCONF)
2218                 rtm->rtm_protocol = RTPROT_KERNEL;
2219         else if (rt->rt6i_flags&RTF_DEFAULT)
2220                 rtm->rtm_protocol = RTPROT_RA;
2221
2222         if (rt->rt6i_flags&RTF_CACHE)
2223                 rtm->rtm_flags |= RTM_F_CLONED;
2224
2225         if (dst) {
2226                 NLA_PUT(skb, RTA_DST, 16, dst);
2227                 rtm->rtm_dst_len = 128;
2228         } else if (rtm->rtm_dst_len)
2229                 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2230 #ifdef CONFIG_IPV6_SUBTREES
2231         if (src) {
2232                 NLA_PUT(skb, RTA_SRC, 16, src);
2233                 rtm->rtm_src_len = 128;
2234         } else if (rtm->rtm_src_len)
2235                 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2236 #endif
2237         if (iif) {
2238 #ifdef CONFIG_IPV6_MROUTE
2239                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2240                         int err = ip6mr_get_route(net, skb, rtm, nowait);
2241                         if (err <= 0) {
2242                                 if (!nowait) {
2243                                         if (err == 0)
2244                                                 return 0;
2245                                         goto nla_put_failure;
2246                                 } else {
2247                                         if (err == -EMSGSIZE)
2248                                                 goto nla_put_failure;
2249                                 }
2250                         }
2251                 } else
2252 #endif
2253                         NLA_PUT_U32(skb, RTA_IIF, iif);
2254         } else if (dst) {
2255                 struct inet6_dev *idev = ip6_dst_idev(&rt->u.dst);
2256                 struct in6_addr saddr_buf;
2257                 if (ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2258                                        dst, 0, &saddr_buf) == 0)
2259                         NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2260         }
2261
2262         if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2263                 goto nla_put_failure;
2264
2265         if (rt->u.dst.neighbour)
2266                 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2267
2268         if (rt->u.dst.dev)
2269                 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2270
2271         NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2272
2273         if (!(rt->rt6i_flags & RTF_EXPIRES))
2274                 expires = 0;
2275         else if (rt->rt6i_expires - jiffies < INT_MAX)
2276                 expires = rt->rt6i_expires - jiffies;
2277         else
2278                 expires = INT_MAX;
2279
2280         if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2281                                expires, rt->u.dst.error) < 0)
2282                 goto nla_put_failure;
2283
2284         return nlmsg_end(skb, nlh);
2285
2286 nla_put_failure:
2287         nlmsg_cancel(skb, nlh);
2288         return -EMSGSIZE;
2289 }
2290
2291 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2292 {
2293         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2294         int prefix;
2295
2296         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2297                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2298                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2299         } else
2300                 prefix = 0;
2301
2302         return rt6_fill_node(arg->net,
2303                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2304                      NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2305                      prefix, 0, NLM_F_MULTI);
2306 }
2307
2308 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2309 {
2310         struct net *net = sock_net(in_skb->sk);
2311         struct nlattr *tb[RTA_MAX+1];
2312         struct rt6_info *rt;
2313         struct sk_buff *skb;
2314         struct rtmsg *rtm;
2315         struct flowi fl;
2316         int err, iif = 0;
2317
2318         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2319         if (err < 0)
2320                 goto errout;
2321
2322         err = -EINVAL;
2323         memset(&fl, 0, sizeof(fl));
2324
2325         if (tb[RTA_SRC]) {
2326                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2327                         goto errout;
2328
2329                 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2330         }
2331
2332         if (tb[RTA_DST]) {
2333                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2334                         goto errout;
2335
2336                 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2337         }
2338
2339         if (tb[RTA_IIF])
2340                 iif = nla_get_u32(tb[RTA_IIF]);
2341
2342         if (tb[RTA_OIF])
2343                 fl.oif = nla_get_u32(tb[RTA_OIF]);
2344
2345         if (iif) {
2346                 struct net_device *dev;
2347                 dev = __dev_get_by_index(net, iif);
2348                 if (!dev) {
2349                         err = -ENODEV;
2350                         goto errout;
2351                 }
2352         }
2353
2354         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2355         if (skb == NULL) {
2356                 err = -ENOBUFS;
2357                 goto errout;
2358         }
2359
2360         /* Reserve room for dummy headers, this skb can pass
2361            through good chunk of routing engine.
2362          */
2363         skb_reset_mac_header(skb);
2364         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2365
2366         rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl);
2367         skb_dst_set(skb, &rt->u.dst);
2368
2369         err = rt6_fill_node(net, skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2370                             RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2371                             nlh->nlmsg_seq, 0, 0, 0);
2372         if (err < 0) {
2373                 kfree_skb(skb);
2374                 goto errout;
2375         }
2376
2377         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2378 errout:
2379         return err;
2380 }
2381
2382 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2383 {
2384         struct sk_buff *skb;
2385         struct net *net = info->nl_net;
2386         u32 seq;
2387         int err;
2388
2389         err = -ENOBUFS;
2390         seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2391
2392         skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2393         if (skb == NULL)
2394                 goto errout;
2395
2396         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2397                                 event, info->pid, seq, 0, 0, 0);
2398         if (err < 0) {
2399                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2400                 WARN_ON(err == -EMSGSIZE);
2401                 kfree_skb(skb);
2402                 goto errout;
2403         }
2404         rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
2405                     info->nlh, gfp_any());
2406         return;
2407 errout:
2408         if (err < 0)
2409                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2410 }
2411
2412 static int ip6_route_dev_notify(struct notifier_block *this,
2413                                 unsigned long event, void *data)
2414 {
2415         struct net_device *dev = (struct net_device *)data;
2416         struct net *net = dev_net(dev);
2417
2418         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2419                 net->ipv6.ip6_null_entry->u.dst.dev = dev;
2420                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2421 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2422                 net->ipv6.ip6_prohibit_entry->u.dst.dev = dev;
2423                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2424                 net->ipv6.ip6_blk_hole_entry->u.dst.dev = dev;
2425                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2426 #endif
2427         }
2428
2429         return NOTIFY_OK;
2430 }
2431
2432 /*
2433  *      /proc
2434  */
2435
2436 #ifdef CONFIG_PROC_FS
2437
2438 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2439
2440 struct rt6_proc_arg
2441 {
2442         char *buffer;
2443         int offset;
2444         int length;
2445         int skip;
2446         int len;
2447 };
2448
2449 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2450 {
2451         struct seq_file *m = p_arg;
2452
2453         seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
2454
2455 #ifdef CONFIG_IPV6_SUBTREES
2456         seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
2457 #else
2458         seq_puts(m, "00000000000000000000000000000000 00 ");
2459 #endif
2460
2461         if (rt->rt6i_nexthop) {
2462                 seq_printf(m, "%pi6", rt->rt6i_nexthop->primary_key);
2463         } else {
2464                 seq_puts(m, "00000000000000000000000000000000");
2465         }
2466         seq_printf(m, " %08x %08x %08x %08x %8s\n",
2467                    rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2468                    rt->u.dst.__use, rt->rt6i_flags,
2469                    rt->rt6i_dev ? rt->rt6i_dev->name : "");
2470         return 0;
2471 }
2472
2473 static int ipv6_route_show(struct seq_file *m, void *v)
2474 {
2475         struct net *net = (struct net *)m->private;
2476         fib6_clean_all(net, rt6_info_route, 0, m);
2477         return 0;
2478 }
2479
2480 static int ipv6_route_open(struct inode *inode, struct file *file)
2481 {
2482         return single_open_net(inode, file, ipv6_route_show);
2483 }
2484
2485 static const struct file_operations ipv6_route_proc_fops = {
2486         .owner          = THIS_MODULE,
2487         .open           = ipv6_route_open,
2488         .read           = seq_read,
2489         .llseek         = seq_lseek,
2490         .release        = single_release_net,
2491 };
2492
2493 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2494 {
2495         struct net *net = (struct net *)seq->private;
2496         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2497                    net->ipv6.rt6_stats->fib_nodes,
2498                    net->ipv6.rt6_stats->fib_route_nodes,
2499                    net->ipv6.rt6_stats->fib_rt_alloc,
2500                    net->ipv6.rt6_stats->fib_rt_entries,
2501                    net->ipv6.rt6_stats->fib_rt_cache,
2502                    atomic_read(&net->ipv6.ip6_dst_ops.entries),
2503                    net->ipv6.rt6_stats->fib_discarded_routes);
2504
2505         return 0;
2506 }
2507
2508 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2509 {
2510         return single_open_net(inode, file, rt6_stats_seq_show);
2511 }
2512
2513 static const struct file_operations rt6_stats_seq_fops = {
2514         .owner   = THIS_MODULE,
2515         .open    = rt6_stats_seq_open,
2516         .read    = seq_read,
2517         .llseek  = seq_lseek,
2518         .release = single_release_net,
2519 };
2520 #endif  /* CONFIG_PROC_FS */
2521
2522 #ifdef CONFIG_SYSCTL
2523
2524 static
2525 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
2526                               void __user *buffer, size_t *lenp, loff_t *ppos)
2527 {
2528         struct net *net = current->nsproxy->net_ns;
2529         int delay = net->ipv6.sysctl.flush_delay;
2530         if (write) {
2531                 proc_dointvec(ctl, write, buffer, lenp, ppos);
2532                 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
2533                 return 0;
2534         } else
2535                 return -EINVAL;
2536 }
2537
2538 ctl_table ipv6_route_table_template[] = {
2539         {
2540                 .procname       =       "flush",
2541                 .data           =       &init_net.ipv6.sysctl.flush_delay,
2542                 .maxlen         =       sizeof(int),
2543                 .mode           =       0200,
2544                 .proc_handler   =       ipv6_sysctl_rtcache_flush
2545         },
2546         {
2547                 .procname       =       "gc_thresh",
2548                 .data           =       &ip6_dst_ops_template.gc_thresh,
2549                 .maxlen         =       sizeof(int),
2550                 .mode           =       0644,
2551                 .proc_handler   =       proc_dointvec,
2552         },
2553         {
2554                 .procname       =       "max_size",
2555                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
2556                 .maxlen         =       sizeof(int),
2557                 .mode           =       0644,
2558                 .proc_handler   =       proc_dointvec,
2559         },
2560         {
2561                 .procname       =       "gc_min_interval",
2562                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2563                 .maxlen         =       sizeof(int),
2564                 .mode           =       0644,
2565                 .proc_handler   =       proc_dointvec_jiffies,
2566         },
2567         {
2568                 .procname       =       "gc_timeout",
2569                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2570                 .maxlen         =       sizeof(int),
2571                 .mode           =       0644,
2572                 .proc_handler   =       proc_dointvec_jiffies,
2573         },
2574         {
2575                 .procname       =       "gc_interval",
2576                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2577                 .maxlen         =       sizeof(int),
2578                 .mode           =       0644,
2579                 .proc_handler   =       proc_dointvec_jiffies,
2580         },
2581         {
2582                 .procname       =       "gc_elasticity",
2583                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2584                 .maxlen         =       sizeof(int),
2585                 .mode           =       0644,
2586                 .proc_handler   =       proc_dointvec_jiffies,
2587         },
2588         {
2589                 .procname       =       "mtu_expires",
2590                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2591                 .maxlen         =       sizeof(int),
2592                 .mode           =       0644,
2593                 .proc_handler   =       proc_dointvec_jiffies,
2594         },
2595         {
2596                 .procname       =       "min_adv_mss",
2597                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2598                 .maxlen         =       sizeof(int),
2599                 .mode           =       0644,
2600                 .proc_handler   =       proc_dointvec_jiffies,
2601         },
2602         {
2603                 .procname       =       "gc_min_interval_ms",
2604                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2605                 .maxlen         =       sizeof(int),
2606                 .mode           =       0644,
2607                 .proc_handler   =       proc_dointvec_ms_jiffies,
2608         },
2609         { }
2610 };
2611
2612 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2613 {
2614         struct ctl_table *table;
2615
2616         table = kmemdup(ipv6_route_table_template,
2617                         sizeof(ipv6_route_table_template),
2618                         GFP_KERNEL);
2619
2620         if (table) {
2621                 table[0].data = &net->ipv6.sysctl.flush_delay;
2622                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2623                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2624                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2625                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2626                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2627                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2628                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2629                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2630                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2631         }
2632
2633         return table;
2634 }
2635 #endif
2636
2637 static int __net_init ip6_route_net_init(struct net *net)
2638 {
2639         int ret = -ENOMEM;
2640
2641         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
2642                sizeof(net->ipv6.ip6_dst_ops));
2643
2644         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
2645                                            sizeof(*net->ipv6.ip6_null_entry),
2646                                            GFP_KERNEL);
2647         if (!net->ipv6.ip6_null_entry)
2648                 goto out_ip6_dst_ops;
2649         net->ipv6.ip6_null_entry->u.dst.path =
2650                 (struct dst_entry *)net->ipv6.ip6_null_entry;
2651         net->ipv6.ip6_null_entry->u.dst.ops = &net->ipv6.ip6_dst_ops;
2652
2653 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2654         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
2655                                                sizeof(*net->ipv6.ip6_prohibit_entry),
2656                                                GFP_KERNEL);
2657         if (!net->ipv6.ip6_prohibit_entry)
2658                 goto out_ip6_null_entry;
2659         net->ipv6.ip6_prohibit_entry->u.dst.path =
2660                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2661         net->ipv6.ip6_prohibit_entry->u.dst.ops = &net->ipv6.ip6_dst_ops;
2662
2663         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
2664                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
2665                                                GFP_KERNEL);
2666         if (!net->ipv6.ip6_blk_hole_entry)
2667                 goto out_ip6_prohibit_entry;
2668         net->ipv6.ip6_blk_hole_entry->u.dst.path =
2669                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2670         net->ipv6.ip6_blk_hole_entry->u.dst.ops = &net->ipv6.ip6_dst_ops;
2671 #endif
2672
2673         net->ipv6.sysctl.flush_delay = 0;
2674         net->ipv6.sysctl.ip6_rt_max_size = 4096;
2675         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
2676         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
2677         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
2678         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
2679         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
2680         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
2681
2682 #ifdef CONFIG_PROC_FS
2683         proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
2684         proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2685 #endif
2686         net->ipv6.ip6_rt_gc_expire = 30*HZ;
2687
2688         ret = 0;
2689 out:
2690         return ret;
2691
2692 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2693 out_ip6_prohibit_entry:
2694         kfree(net->ipv6.ip6_prohibit_entry);
2695 out_ip6_null_entry:
2696         kfree(net->ipv6.ip6_null_entry);
2697 #endif
2698 out_ip6_dst_ops:
2699         goto out;
2700 }
2701
2702 static void __net_exit ip6_route_net_exit(struct net *net)
2703 {
2704 #ifdef CONFIG_PROC_FS
2705         proc_net_remove(net, "ipv6_route");
2706         proc_net_remove(net, "rt6_stats");
2707 #endif
2708         kfree(net->ipv6.ip6_null_entry);
2709 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2710         kfree(net->ipv6.ip6_prohibit_entry);
2711         kfree(net->ipv6.ip6_blk_hole_entry);
2712 #endif
2713 }
2714
2715 static struct pernet_operations ip6_route_net_ops = {
2716         .init = ip6_route_net_init,
2717         .exit = ip6_route_net_exit,
2718 };
2719
2720 static struct notifier_block ip6_route_dev_notifier = {
2721         .notifier_call = ip6_route_dev_notify,
2722         .priority = 0,
2723 };
2724
2725 int __init ip6_route_init(void)
2726 {
2727         int ret;
2728
2729         ret = -ENOMEM;
2730         ip6_dst_ops_template.kmem_cachep =
2731                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2732                                   SLAB_HWCACHE_ALIGN, NULL);
2733         if (!ip6_dst_ops_template.kmem_cachep)
2734                 goto out;
2735
2736         ret = register_pernet_subsys(&ip6_route_net_ops);
2737         if (ret)
2738                 goto out_kmem_cache;
2739
2740         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
2741
2742         /* Registering of the loopback is done before this portion of code,
2743          * the loopback reference in rt6_info will not be taken, do it
2744          * manually for init_net */
2745         init_net.ipv6.ip6_null_entry->u.dst.dev = init_net.loopback_dev;
2746         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2747   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2748         init_net.ipv6.ip6_prohibit_entry->u.dst.dev = init_net.loopback_dev;
2749         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2750         init_net.ipv6.ip6_blk_hole_entry->u.dst.dev = init_net.loopback_dev;
2751         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2752   #endif
2753         ret = fib6_init();
2754         if (ret)
2755                 goto out_register_subsys;
2756
2757         ret = xfrm6_init();
2758         if (ret)
2759                 goto out_fib6_init;
2760
2761         ret = fib6_rules_init();
2762         if (ret)
2763                 goto xfrm6_init;
2764
2765         ret = -ENOBUFS;
2766         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
2767             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
2768             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
2769                 goto fib6_rules_init;
2770
2771         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
2772         if (ret)
2773                 goto fib6_rules_init;
2774
2775 out:
2776         return ret;
2777
2778 fib6_rules_init:
2779         fib6_rules_cleanup();
2780 xfrm6_init:
2781         xfrm6_fini();
2782 out_fib6_init:
2783         fib6_gc_cleanup();
2784 out_register_subsys:
2785         unregister_pernet_subsys(&ip6_route_net_ops);
2786 out_kmem_cache:
2787         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2788         goto out;
2789 }
2790
2791 void ip6_route_cleanup(void)
2792 {
2793         unregister_netdevice_notifier(&ip6_route_dev_notifier);
2794         fib6_rules_cleanup();
2795         xfrm6_fini();
2796         fib6_gc_cleanup();
2797         unregister_pernet_subsys(&ip6_route_net_ops);
2798         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2799 }