kernel-routes.patch

   1 diff -urp v2.6.27/linux/include/linux/rtnetlink.h linux/include/linux/rtnetlink.h
   2 --- v2.6.27/linux/include/linux/rtnetlink.h     2008-10-11 12:46:15.000000000 +0300
   3 +++ linux/include/linux/rtnetlink.h     2008-10-11 13:50:41.000000000 +0300
   4 @@ -304,6 +304,8 @@ struct rtnexthop
   5  #define RTNH_F_DEAD            1       /* Nexthop is dead (used by multipath)  */
   6  #define RTNH_F_PERVASIVE       2       /* Do recursive gateway lookup  */
   7  #define RTNH_F_ONLINK          4       /* Gateway is forced on link    */
   8 +#define RTNH_F_SUSPECT         8       /* We don't know the real state */
   9 +#define RTNH_F_BADSTATE                (RTNH_F_DEAD | RTNH_F_SUSPECT)
  10
  11  /* Macros to handle hexthops */
  12
  13 diff -urp v2.6.27/linux/include/net/flow.h linux/include/net/flow.h
  14 --- v2.6.27/linux/include/net/flow.h    2008-10-11 12:46:15.000000000 +0300
  15 +++ linux/include/net/flow.h    2008-10-11 13:51:37.000000000 +0300
  16 @@ -19,6 +19,8 @@ struct flowi {
  17                 struct {
  18                         __be32                  daddr;
  19                         __be32                  saddr;
  20 +                       __be32                  lsrc;
  21 +                       __be32                  gw;
  22                         __u8                    tos;
  23                         __u8                    scope;
  24                 } ip4_u;
  25 @@ -43,6 +45,8 @@ struct flowi {
  26  #define fl6_flowlabel  nl_u.ip6_u.flowlabel
  27  #define fl4_dst                nl_u.ip4_u.daddr
  28  #define fl4_src                nl_u.ip4_u.saddr
  29 +#define fl4_lsrc       nl_u.ip4_u.lsrc
  30 +#define fl4_gw         nl_u.ip4_u.gw
  31  #define fl4_tos                nl_u.ip4_u.tos
  32  #define fl4_scope      nl_u.ip4_u.scope
  33
  34 diff -urp v2.6.27/linux/include/net/ip_fib.h linux/include/net/ip_fib.h
  35 --- v2.6.27/linux/include/net/ip_fib.h  2008-04-17 09:58:08.000000000 +0300
  36 +++ linux/include/net/ip_fib.h  2008-10-11 13:50:41.000000000 +0300
  37 @@ -207,6 +207,8 @@ extern int fib_lookup(struct net *n, str
  38  extern struct fib_table *fib_new_table(struct net *net, u32 id);
  39  extern struct fib_table *fib_get_table(struct net *net, u32 id);
  40
  41 +extern int fib_result_table(struct fib_result *res);
  42 +
  43  #endif /* CONFIG_IP_MULTIPLE_TABLES */
  44
  45  /* Exported by fib_frontend.c */
  46 @@ -276,4 +278,6 @@ static inline void fib_proc_exit(struct
  47  }
  48  #endif
  49
  50 +extern rwlock_t fib_nhflags_lock;
  51 +
  52  #endif  /* _NET_FIB_H */
  53 diff -urp v2.6.27/linux/include/net/netfilter/nf_nat.h linux/include/net/netfilter/nf_nat.h
  54 --- v2.6.27/linux/include/net/netfilter/nf_nat.h        2008-04-17 09:58:08.000000000 +0300
  55 +++ linux/include/net/netfilter/nf_nat.h        2008-10-11 13:51:37.000000000 +0300
  56 @@ -77,6 +77,13 @@ struct nf_conn_nat
  57  #endif
  58  };
  59
  60 +/* Call input routing for SNAT-ed traffic */
  61 +extern unsigned int ip_nat_route_input(unsigned int hooknum,
  62 +                                      struct sk_buff *skb,
  63 +                                      const struct net_device *in,
  64 +                                      const struct net_device *out,
  65 +                                      int (*okfn)(struct sk_buff *));
  66 +
  67  /* Set up the info structure to map into this range. */
  68  extern unsigned int nf_nat_setup_info(struct nf_conn *ct,
  69                                       const struct nf_nat_range *range,
  70 diff -urp v2.6.27/linux/include/net/route.h linux/include/net/route.h
  71 --- v2.6.27/linux/include/net/route.h   2008-10-11 12:46:15.000000000 +0300
  72 +++ linux/include/net/route.h   2008-10-11 13:51:37.000000000 +0300
  73 @@ -116,6 +116,7 @@ extern int          __ip_route_output_key(struct
  74  extern int             ip_route_output_key(struct net *, struct rtable **, struct flowi *flp);
  75  extern int             ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk, int flags);
  76  extern int             ip_route_input(struct sk_buff*, __be32 dst, __be32 src, u8 tos, struct net_device *devin);
  77 +extern int             ip_route_input_lookup(struct sk_buff*, __be32 dst, __be32 src, u8 tos, struct net_device *devin, __be32 lsrc);
  78  extern unsigned short  ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev);
  79  extern void            ip_rt_send_redirect(struct sk_buff *skb);
  80
  81 diff -urp v2.6.27/linux/net/bridge/br_netfilter.c linux/net/bridge/br_netfilter.c
  82 --- v2.6.27/linux/net/bridge/br_netfilter.c     2008-10-11 12:46:16.000000000 +0300
  83 +++ linux/net/bridge/br_netfilter.c     2008-10-11 13:51:37.000000000 +0300
  84 @@ -328,6 +328,10 @@ static int br_nf_pre_routing_finish(stru
  85         struct nf_bridge_info *nf_bridge = skb->nf_bridge;
  86         int err;
  87
  88 +       /* Old skb->dst is not expected, it is lost in all cases */
  89 +       dst_release(skb->dst);
  90 +       skb->dst = NULL;
  91 +
  92         if (nf_bridge->mask & BRNF_PKT_TYPE) {
  93                 skb->pkt_type = PACKET_OTHERHOST;
  94                 nf_bridge->mask ^= BRNF_PKT_TYPE;
  95 diff -urp v2.6.27/linux/net/ipv4/fib_frontend.c linux/net/ipv4/fib_frontend.c
  96 --- v2.6.27/linux/net/ipv4/fib_frontend.c       2008-10-11 12:46:16.000000000 +0300
  97 +++ linux/net/ipv4/fib_frontend.c       2008-10-11 13:50:41.000000000 +0300
  98 @@ -47,6 +47,8 @@
  99
 100  #ifndef CONFIG_IP_MULTIPLE_TABLES
 101
 102 +#define FIB_RES_TABLE(r) (RT_TABLE_MAIN)
 103 +
 104  static int __net_init fib4_rules_init(struct net *net)
 105  {
 106         struct fib_table *local_table, *main_table;
 107 @@ -71,6 +73,8 @@ fail:
 108  }
 109  #else
 110
 111 +#define FIB_RES_TABLE(r) (fib_result_table(r))
 112 +
 113  struct fib_table *fib_new_table(struct net *net, u32 id)
 114  {
 115         struct fib_table *tb;
 116 @@ -125,7 +129,8 @@ void fib_select_default(struct net *net,
 117         table = res->r->table;
 118  #endif
 119         tb = fib_get_table(net, table);
 120 -       if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 121 +       if ((FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) ||
 122 +           FIB_RES_NH(*res).nh_scope == RT_SCOPE_HOST)
 123                 tb->tb_select_default(tb, flp, res);
 124  }
 125
 126 @@ -239,6 +244,9 @@ int fib_validate_source(__be32 src, __be
 127                                         .tos = tos } },
 128                             .iif = oif };
 129         struct fib_result res;
 130 +       int table;
 131 +       unsigned char prefixlen;
 132 +       unsigned char scope;
 133         int no_addr, rpf;
 134         int ret;
 135         struct net *net;
 136 @@ -262,31 +270,35 @@ int fib_validate_source(__be32 src, __be
 137                 goto e_inval_res;
 138         *spec_dst = FIB_RES_PREFSRC(res);
 139         fib_combine_itag(itag, &res);
 140 -#ifdef CONFIG_IP_ROUTE_MULTIPATH
 141 -       if (FIB_RES_DEV(res) == dev || res.fi->fib_nhs > 1)
 142 -#else
 143         if (FIB_RES_DEV(res) == dev)
 144 -#endif
 145         {
 146                 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
 147                 fib_res_put(&res);
 148                 return ret;
 149         }
 150 +       table = FIB_RES_TABLE(&res);
 151 +       prefixlen = res.prefixlen;
 152 +       scope = res.scope;
 153         fib_res_put(&res);
 154         if (no_addr)
 155                 goto last_resort;
 156 -       if (rpf)
 157 -               goto e_inval;
 158         fl.oif = dev->ifindex;
 159
 160         ret = 0;
 161         if (fib_lookup(net, &fl, &res) == 0) {
 162 -               if (res.type == RTN_UNICAST) {
 163 +               if (res.type == RTN_UNICAST &&
 164 +                   ((table == FIB_RES_TABLE(&res) &&
 165 +                     res.prefixlen >= prefixlen && res.scope >= scope) ||
 166 +                    !rpf)) {
 167                         *spec_dst = FIB_RES_PREFSRC(res);
 168                         ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
 169 +                       fib_res_put(&res);
 170 +                       return ret;
 171                 }
 172                 fib_res_put(&res);
 173         }
 174 +       if (rpf)
 175 +               goto e_inval;
 176         return ret;
 177
 178  last_resort:
 179 @@ -909,9 +921,7 @@ static int fib_inetaddr_event(struct not
 180         switch (event) {
 181         case NETDEV_UP:
 182                 fib_add_ifaddr(ifa);
 183 -#ifdef CONFIG_IP_ROUTE_MULTIPATH
 184                 fib_sync_up(dev);
 185 -#endif
 186                 rt_cache_flush(dev_net(dev), -1);
 187                 break;
 188         case NETDEV_DOWN:
 189 @@ -947,9 +957,7 @@ static int fib_netdev_event(struct notif
 190                 for_ifa(in_dev) {
 191                         fib_add_ifaddr(ifa);
 192                 } endfor_ifa(in_dev);
 193 -#ifdef CONFIG_IP_ROUTE_MULTIPATH
 194                 fib_sync_up(dev);
 195 -#endif
 196                 rt_cache_flush(dev_net(dev), -1);
 197                 break;
 198         case NETDEV_DOWN:
 199 diff -urp v2.6.27/linux/net/ipv4/fib_hash.c linux/net/ipv4/fib_hash.c
 200 --- v2.6.27/linux/net/ipv4/fib_hash.c   2008-10-11 12:46:16.000000000 +0300
 201 +++ linux/net/ipv4/fib_hash.c   2008-10-11 13:50:41.000000000 +0300
 202 @@ -278,25 +278,35 @@ out:
 203  static void
 204  fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
 205  {
 206 -       int order, last_idx;
 207 +       int order, last_idx, last_dflt, last_nhsel;
 208 +       struct fib_alias *first_fa = NULL;
 209 +       struct hlist_head *head;
 210         struct hlist_node *node;
 211         struct fib_node *f;
 212         struct fib_info *fi = NULL;
 213         struct fib_info *last_resort;
 214         struct fn_hash *t = (struct fn_hash*)tb->tb_data;
 215 -       struct fn_zone *fz = t->fn_zones[0];
 216 +       struct fn_zone *fz = t->fn_zones[res->prefixlen];
 217 +       __be32 k;
 218
 219         if (fz == NULL)
 220                 return;
 221
 222 +       k = fz_key(flp->fl4_dst, fz);
 223 +       last_dflt = -2;
 224 +       last_nhsel = 0;
 225         last_idx = -1;
 226         last_resort = NULL;
 227         order = -1;
 228
 229         read_lock(&fib_hash_lock);
 230 -       hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) {
 231 +       head = &fz->fz_hash[fn_hash(k, fz)];
 232 +       hlist_for_each_entry(f, node, head, fn_hash) {
 233                 struct fib_alias *fa;
 234
 235 +               if (f->fn_key != k)
 236 +                       continue;
 237 +
 238                 list_for_each_entry(fa, &f->fn_alias, fa_list) {
 239                         struct fib_info *next_fi = fa->fa_info;
 240
 241 @@ -304,42 +314,56 @@ fn_hash_select_default(struct fib_table
 242                             fa->fa_type != RTN_UNICAST)
 243                                 continue;
 244
 245 +                       if (fa->fa_tos &&
 246 +                           fa->fa_tos != flp->fl4_tos)
 247 +                               continue;
 248                         if (next_fi->fib_priority > res->fi->fib_priority)
 249                                 break;
 250 -                       if (!next_fi->fib_nh[0].nh_gw ||
 251 -                           next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
 252 -                               continue;
 253                         fa->fa_state |= FA_S_ACCESSED;
 254
 255 -                       if (fi == NULL) {
 256 -                               if (next_fi != res->fi)
 257 -                                       break;
 258 -                       } else if (!fib_detect_death(fi, order, &last_resort,
 259 -                                               &last_idx, tb->tb_default)) {
 260 +                       if (!first_fa) {
 261 +                               last_dflt = fa->fa_last_dflt;
 262 +                               first_fa = fa;
 263 +                       }
 264 +                       if (fi && !fib_detect_death(fi, order, &last_resort,
 265 +                               &last_idx, &last_dflt, &last_nhsel, flp)) {
 266                                 fib_result_assign(res, fi);
 267 -                               tb->tb_default = order;
 268 +                               first_fa->fa_last_dflt = order;
 269                                 goto out;
 270                         }
 271                         fi = next_fi;
 272                         order++;
 273                 }
 274 +               break;
 275         }
 276
 277         if (order <= 0 || fi == NULL) {
 278 -               tb->tb_default = -1;
 279 +               if (fi && fi->fib_nhs > 1 &&
 280 +                   fib_detect_death(fi, order, &last_resort, &last_idx,
 281 +                       &last_dflt, &last_nhsel, flp) &&
 282 +                   last_resort == fi) {
 283 +                       read_lock_bh(&fib_nhflags_lock);
 284 +                       fi->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
 285 +                       read_unlock_bh(&fib_nhflags_lock);
 286 +               }
 287 +               if (first_fa) first_fa->fa_last_dflt = -1;
 288                 goto out;
 289         }
 290
 291         if (!fib_detect_death(fi, order, &last_resort, &last_idx,
 292 -                               tb->tb_default)) {
 293 +                             &last_dflt, &last_nhsel, flp)) {
 294                 fib_result_assign(res, fi);
 295 -               tb->tb_default = order;
 296 +               first_fa->fa_last_dflt = order;
 297                 goto out;
 298         }
 299
 300 -       if (last_idx >= 0)
 301 +       if (last_idx >= 0) {
 302                 fib_result_assign(res, last_resort);
 303 -       tb->tb_default = last_idx;
 304 +               read_lock_bh(&fib_nhflags_lock);
 305 +               last_resort->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
 306 +               read_unlock_bh(&fib_nhflags_lock);
 307 +               first_fa->fa_last_dflt = last_idx;
 308 +       }
 309  out:
 310         read_unlock(&fib_hash_lock);
 311  }
 312 @@ -463,6 +487,7 @@ static int fn_hash_insert(struct fib_tab
 313                         write_lock_bh(&fib_hash_lock);
 314                         fi_drop = fa->fa_info;
 315                         fa->fa_info = fi;
 316 +                       fa->fa_last_dflt = -1;
 317                         fa->fa_type = cfg->fc_type;
 318                         fa->fa_scope = cfg->fc_scope;
 319                         state = fa->fa_state;
 320 @@ -517,6 +542,7 @@ static int fn_hash_insert(struct fib_tab
 321         new_fa->fa_type = cfg->fc_type;
 322         new_fa->fa_scope = cfg->fc_scope;
 323         new_fa->fa_state = 0;
 324 +       new_fa->fa_last_dflt = -1;
 325
 326         /*
 327          * Insert new entry to the list.
 328 diff -urp v2.6.27/linux/net/ipv4/fib_lookup.h linux/net/ipv4/fib_lookup.h
 329 --- v2.6.27/linux/net/ipv4/fib_lookup.h 2008-04-17 09:58:09.000000000 +0300
 330 +++ linux/net/ipv4/fib_lookup.h 2008-10-11 13:50:41.000000000 +0300
 331 @@ -8,6 +8,7 @@
 332  struct fib_alias {
 333         struct list_head        fa_list;
 334         struct fib_info         *fa_info;
 335 +       int                     fa_last_dflt;
 336         u8                      fa_tos;
 337         u8                      fa_type;
 338         u8                      fa_scope;
 339 @@ -38,7 +39,8 @@ extern struct fib_alias *fib_find_alias(
 340                                         u8 tos, u32 prio);
 341  extern int fib_detect_death(struct fib_info *fi, int order,
 342                             struct fib_info **last_resort,
 343 -                           int *last_idx, int dflt);
 344 +                           int *last_idx, int *dflt, int *last_nhsel,
 345 +                           const struct flowi *flp);
 346
 347  static inline void fib_result_assign(struct fib_result *res,
 348                                      struct fib_info *fi)
 349 diff -urp v2.6.27/linux/net/ipv4/fib_rules.c linux/net/ipv4/fib_rules.c
 350 --- v2.6.27/linux/net/ipv4/fib_rules.c  2008-10-11 12:46:16.000000000 +0300
 351 +++ linux/net/ipv4/fib_rules.c  2008-10-11 13:50:41.000000000 +0300
 352 @@ -54,6 +54,11 @@ u32 fib_rules_tclass(struct fib_result *
 353  }
 354  #endif
 355
 356 +int fib_result_table(struct fib_result *res)
 357 +{
 358 +       return res->r->table;
 359 +}
 360 +
 361  int fib_lookup(struct net *net, struct flowi *flp, struct fib_result *res)
 362  {
 363         struct fib_lookup_arg arg = {
 364 diff -urp v2.6.27/linux/net/ipv4/fib_semantics.c linux/net/ipv4/fib_semantics.c
 365 --- v2.6.27/linux/net/ipv4/fib_semantics.c      2008-10-11 12:46:16.000000000 +0300
 366 +++ linux/net/ipv4/fib_semantics.c      2008-10-11 13:51:37.000000000 +0300
 367 @@ -50,6 +50,7 @@ static struct hlist_head *fib_info_hash;
 368  static struct hlist_head *fib_info_laddrhash;
 369  static unsigned int fib_hash_size;
 370  static unsigned int fib_info_cnt;
 371 +rwlock_t fib_nhflags_lock = RW_LOCK_UNLOCKED;
 372
 373  #define DEVINDEX_HASHBITS 8
 374  #define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS)
 375 @@ -186,7 +187,7 @@ static __inline__ int nh_comp(const stru
 376  #ifdef CONFIG_NET_CLS_ROUTE
 377                     nh->nh_tclassid != onh->nh_tclassid ||
 378  #endif
 379 -                   ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
 380 +                   ((nh->nh_flags^onh->nh_flags)&~RTNH_F_BADSTATE))
 381                         return -1;
 382                 onh++;
 383         } endfor_nexthops(fi);
 384 @@ -237,7 +238,7 @@ static struct fib_info *fib_find_info(co
 385                     nfi->fib_priority == fi->fib_priority &&
 386                     memcmp(nfi->fib_metrics, fi->fib_metrics,
 387                            sizeof(fi->fib_metrics)) == 0 &&
 388 -                   ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
 389 +                   ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_BADSTATE) == 0 &&
 390                     (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
 391                         return fi;
 392         }
 393 @@ -348,26 +349,70 @@ struct fib_alias *fib_find_alias(struct
 394  }
 395
 396  int fib_detect_death(struct fib_info *fi, int order,
 397 -                    struct fib_info **last_resort, int *last_idx, int dflt)
 398 +                    struct fib_info **last_resort, int *last_idx, int *dflt,
 399 +                    int *last_nhsel, const struct flowi *flp)
 400  {
 401         struct neighbour *n;
 402 -       int state = NUD_NONE;
 403 +       int nhsel;
 404 +       int state;
 405 +       struct fib_nh * nh;
 406 +       __be32 dst;
 407 +       int flag, dead = 1;
 408 +
 409 +       /* change_nexthops(fi) { */
 410 +       for (nhsel = 0, nh = fi->fib_nh; nhsel < fi->fib_nhs; nh++, nhsel++) {
 411 +               if (flp->oif && flp->oif != nh->nh_oif)
 412 +                       continue;
 413 +               if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw && nh->nh_gw &&
 414 +                   nh->nh_scope == RT_SCOPE_LINK)
 415 +                       continue;
 416 +               if (nh->nh_flags & RTNH_F_DEAD)
 417 +                       continue;
 418
 419 -       n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev);
 420 -       if (n) {
 421 -               state = n->nud_state;
 422 -               neigh_release(n);
 423 -       }
 424 -       if (state==NUD_REACHABLE)
 425 -               return 0;
 426 -       if ((state&NUD_VALID) && order != dflt)
 427 -               return 0;
 428 -       if ((state&NUD_VALID) ||
 429 -           (*last_idx<0 && order > dflt)) {
 430 -               *last_resort = fi;
 431 -               *last_idx = order;
 432 +               flag = 0;
 433 +               if (nh->nh_dev->flags & IFF_NOARP) {
 434 +                       dead = 0;
 435 +                       goto setfl;
 436 +               }
 437 +
 438 +               dst = nh->nh_gw;
 439 +               if (!nh->nh_gw || nh->nh_scope != RT_SCOPE_LINK)
 440 +                       dst = flp->fl4_dst;
 441 +
 442 +               state = NUD_NONE;
 443 +               n = neigh_lookup(&arp_tbl, &dst, nh->nh_dev);
 444 +               if (n) {
 445 +                       state = n->nud_state;
 446 +                       neigh_release(n);
 447 +               }
 448 +               if (state==NUD_REACHABLE ||
 449 +                       ((state&NUD_VALID) && order != *dflt)) {
 450 +                       dead = 0;
 451 +                       goto setfl;
 452 +               }
 453 +               if (!(state&NUD_VALID))
 454 +                       flag = 1;
 455 +               if (!dead)
 456 +                       goto setfl;
 457 +               if ((state&NUD_VALID) ||
 458 +                   (*last_idx<0 && order >= *dflt)) {
 459 +                       *last_resort = fi;
 460 +                       *last_idx = order;
 461 +                       *last_nhsel = nhsel;
 462 +               }
 463 +
 464 +               setfl:
 465 +
 466 +               read_lock_bh(&fib_nhflags_lock);
 467 +               if (flag)
 468 +                       nh->nh_flags |= RTNH_F_SUSPECT;
 469 +               else
 470 +                       nh->nh_flags &= ~RTNH_F_SUSPECT;
 471 +               read_unlock_bh(&fib_nhflags_lock);
 472         }
 473 -       return 1;
 474 +       /* } endfor_nexthops(fi) */
 475 +
 476 +       return dead;
 477  }
 478
 479  #ifdef CONFIG_IP_ROUTE_MULTIPATH
 480 @@ -539,8 +584,11 @@ static int fib_check_nh(struct fib_confi
 481                                 return -EINVAL;
 482                         if ((dev = __dev_get_by_index(net, nh->nh_oif)) == NULL)
 483                                 return -ENODEV;
 484 -                       if (!(dev->flags&IFF_UP))
 485 -                               return -ENETDOWN;
 486 +                       if (!(dev->flags&IFF_UP)) {
 487 +                               if (fi->fib_protocol != RTPROT_STATIC)
 488 +                                       return -ENETDOWN;
 489 +                               nh->nh_flags |= RTNH_F_DEAD;
 490 +                       }
 491                         nh->nh_dev = dev;
 492                         dev_hold(dev);
 493                         nh->nh_scope = RT_SCOPE_LINK;
 494 @@ -560,24 +608,48 @@ static int fib_check_nh(struct fib_confi
 495                         /* It is not necessary, but requires a bit of thinking */
 496                         if (fl.fl4_scope < RT_SCOPE_LINK)
 497                                 fl.fl4_scope = RT_SCOPE_LINK;
 498 -                       if ((err = fib_lookup(net, &fl, &res)) != 0)
 499 -                               return err;
 500 +                       err = fib_lookup(net, &fl, &res);
 501                 }
 502 -               err = -EINVAL;
 503 -               if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
 504 -                       goto out;
 505 -               nh->nh_scope = res.scope;
 506 -               nh->nh_oif = FIB_RES_OIF(res);
 507 -               if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
 508 -                       goto out;
 509 -               dev_hold(nh->nh_dev);
 510 -               err = -ENETDOWN;
 511 -               if (!(nh->nh_dev->flags & IFF_UP))
 512 -                       goto out;
 513 -               err = 0;
 514 +               if (err) {
 515 +                       struct in_device *in_dev;
 516 +
 517 +                       if (err != -ENETUNREACH ||
 518 +                           fi->fib_protocol != RTPROT_STATIC)
 519 +                               return err;
 520 +
 521 +                       in_dev = inetdev_by_index(net, nh->nh_oif);
 522 +                       if (in_dev == NULL ||
 523 +                           in_dev->dev->flags & IFF_UP) {
 524 +                               if (in_dev)
 525 +                                       in_dev_put(in_dev);
 526 +                               return err;
 527 +                       }
 528 +                       nh->nh_flags |= RTNH_F_DEAD;
 529 +                       nh->nh_scope = RT_SCOPE_LINK;
 530 +                       nh->nh_dev = in_dev->dev;
 531 +                       dev_hold(nh->nh_dev);
 532 +                       in_dev_put(in_dev);
 533 +               } else {
 534 +                       err = -EINVAL;
 535 +                       if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
 536 +                               goto out;
 537 +                       nh->nh_scope = res.scope;
 538 +                       nh->nh_oif = FIB_RES_OIF(res);
 539 +                       if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
 540 +                               goto out;
 541 +                       dev_hold(nh->nh_dev);
 542 +                       if (!(nh->nh_dev->flags & IFF_UP)) {
 543 +                               if (fi->fib_protocol != RTPROT_STATIC) {
 544 +                                       err = -ENETDOWN;
 545 +                                       goto out;
 546 +                               }
 547 +                               nh->nh_flags |= RTNH_F_DEAD;
 548 +                       }
 549 +                       err = 0;
 550  out:
 551 -               fib_res_put(&res);
 552 -               return err;
 553 +                       fib_res_put(&res);
 554 +                       return err;
 555 +               }
 556         } else {
 557                 struct in_device *in_dev;
 558
 559 @@ -588,8 +660,11 @@ out:
 560                 if (in_dev == NULL)
 561                         return -ENODEV;
 562                 if (!(in_dev->dev->flags&IFF_UP)) {
 563 -                       in_dev_put(in_dev);
 564 -                       return -ENETDOWN;
 565 +                       if (fi->fib_protocol != RTPROT_STATIC) {
 566 +                               in_dev_put(in_dev);
 567 +                               return -ENETDOWN;
 568 +                       }
 569 +                       nh->nh_flags |= RTNH_F_DEAD;
 570                 }
 571                 nh->nh_dev = in_dev->dev;
 572                 dev_hold(nh->nh_dev);
 573 @@ -899,8 +974,12 @@ int fib_semantic_match(struct list_head
 574                                 for_nexthops(fi) {
 575                                         if (nh->nh_flags&RTNH_F_DEAD)
 576                                                 continue;
 577 -                                       if (!flp->oif || flp->oif == nh->nh_oif)
 578 -                                               break;
 579 +                                       if (flp->oif && flp->oif != nh->nh_oif)
 580 +                                               continue;
 581 +                                       if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
 582 +                                           nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
 583 +                                               continue;
 584 +                                       break;
 585                                 }
 586  #ifdef CONFIG_IP_ROUTE_MULTIPATH
 587                                 if (nhsel < fi->fib_nhs) {
 588 @@ -1080,18 +1159,29 @@ int fib_sync_down_dev(struct net_device
 589                 prev_fi = fi;
 590                 dead = 0;
 591                 change_nexthops(fi) {
 592 -                       if (nh->nh_flags&RTNH_F_DEAD)
 593 -                               dead++;
 594 -                       else if (nh->nh_dev == dev &&
 595 -                                       nh->nh_scope != scope) {
 596 -                               nh->nh_flags |= RTNH_F_DEAD;
 597 +                       if (nh->nh_flags&RTNH_F_DEAD) {
 598 +                               if (fi->fib_protocol!=RTPROT_STATIC ||
 599 +                                   nh->nh_dev == NULL ||
 600 +                                   __in_dev_get_rtnl(nh->nh_dev) == NULL ||
 601 +                                   nh->nh_dev->flags&IFF_UP)
 602 +                                       dead++;
 603 +                       } else if (nh->nh_dev == dev &&
 604 +                                  nh->nh_scope != scope) {
 605 +                               write_lock_bh(&fib_nhflags_lock);
 606  #ifdef CONFIG_IP_ROUTE_MULTIPATH
 607 -                               spin_lock_bh(&fib_multipath_lock);
 608 +                               spin_lock(&fib_multipath_lock);
 609 +                               nh->nh_flags |= RTNH_F_DEAD;
 610                                 fi->fib_power -= nh->nh_power;
 611                                 nh->nh_power = 0;
 612 -                               spin_unlock_bh(&fib_multipath_lock);
 613 +                               spin_unlock(&fib_multipath_lock);
 614 +#else
 615 +                               nh->nh_flags |= RTNH_F_DEAD;
 616  #endif
 617 -                               dead++;
 618 +                               write_unlock_bh(&fib_nhflags_lock);
 619 +                               if (fi->fib_protocol!=RTPROT_STATIC ||
 620 +                                   force ||
 621 +                                   __in_dev_get_rtnl(dev) == NULL)
 622 +                                       dead++;
 623                         }
 624  #ifdef CONFIG_IP_ROUTE_MULTIPATH
 625                         if (force > 1 && nh->nh_dev == dev) {
 626 @@ -1109,11 +1199,8 @@ int fib_sync_down_dev(struct net_device
 627         return ret;
 628  }
 629
 630 -#ifdef CONFIG_IP_ROUTE_MULTIPATH
 631 -
 632  /*
 633 -   Dead device goes up. We wake up dead nexthops.
 634 -   It takes sense only on multipath routes.
 635 +   Dead device goes up or new address is added. We wake up dead nexthops.
 636   */
 637
 638  int fib_sync_up(struct net_device *dev)
 639 @@ -1123,8 +1210,10 @@ int fib_sync_up(struct net_device *dev)
 640         struct hlist_head *head;
 641         struct hlist_node *node;
 642         struct fib_nh *nh;
 643 -       int ret;
 644 +       struct fib_result res;
 645 +       int ret, rep;
 646
 647 +repeat:
 648         if (!(dev->flags&IFF_UP))
 649                 return 0;
 650
 651 @@ -1132,6 +1221,7 @@ int fib_sync_up(struct net_device *dev)
 652         hash = fib_devindex_hashfn(dev->ifindex);
 653         head = &fib_info_devhash[hash];
 654         ret = 0;
 655 +       rep = 0;
 656
 657         hlist_for_each_entry(nh, node, head, nh_hash) {
 658                 struct fib_info *fi = nh->nh_parent;
 659 @@ -1144,19 +1234,39 @@ int fib_sync_up(struct net_device *dev)
 660                 prev_fi = fi;
 661                 alive = 0;
 662                 change_nexthops(fi) {
 663 -                       if (!(nh->nh_flags&RTNH_F_DEAD)) {
 664 -                               alive++;
 665 +                       if (!(nh->nh_flags&RTNH_F_DEAD))
 666                                 continue;
 667 -                       }
 668                         if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
 669                                 continue;
 670                         if (nh->nh_dev != dev || !__in_dev_get_rtnl(dev))
 671                                 continue;
 672 +                       if (nh->nh_gw && fi->fib_protocol == RTPROT_STATIC) {
 673 +                               struct flowi fl = {
 674 +                                       .nl_u = { .ip4_u =
 675 +                                                 { .daddr = nh->nh_gw,
 676 +                                                   .scope = nh->nh_scope } },
 677 +                                       .oif =  nh->nh_oif,
 678 +                               };
 679 +                               if (fib_lookup(dev_net(dev), &fl, &res) != 0)
 680 +                                       continue;
 681 +                               if (res.type != RTN_UNICAST &&
 682 +                                   res.type != RTN_LOCAL) {
 683 +                                       fib_res_put(&res);
 684 +                                       continue;
 685 +                               }
 686 +                               nh->nh_scope = res.scope;
 687 +                               fib_res_put(&res);
 688 +                               rep = 1;
 689 +                       }
 690                         alive++;
 691 +#ifdef CONFIG_IP_ROUTE_MULTIPATH
 692                         spin_lock_bh(&fib_multipath_lock);
 693                         nh->nh_power = 0;
 694 +#endif
 695                         nh->nh_flags &= ~RTNH_F_DEAD;
 696 +#ifdef CONFIG_IP_ROUTE_MULTIPATH
 697                         spin_unlock_bh(&fib_multipath_lock);
 698 +#endif
 699                 } endfor_nexthops(fi)
 700
 701                 if (alive > 0) {
 702 @@ -1164,10 +1274,14 @@ int fib_sync_up(struct net_device *dev)
 703                         ret++;
 704                 }
 705         }
 706 +       if (rep)
 707 +               goto repeat;
 708
 709         return ret;
 710  }
 711
 712 +#ifdef CONFIG_IP_ROUTE_MULTIPATH
 713 +
 714  /*
 715     The algorithm is suboptimal, but it provides really
 716     fair weighted route distribution.
 717 @@ -1176,24 +1290,45 @@ int fib_sync_up(struct net_device *dev)
 718  void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
 719  {
 720         struct fib_info *fi = res->fi;
 721 -       int w;
 722 +       int w, alive;
 723
 724         spin_lock_bh(&fib_multipath_lock);
 725 +       if (flp->oif) {
 726 +               int sel = -1;
 727 +               w = -1;
 728 +               change_nexthops(fi) {
 729 +                       if (flp->oif != nh->nh_oif)
 730 +                               continue;
 731 +                       if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
 732 +                           nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
 733 +                               continue;
 734 +                       if (!(nh->nh_flags&RTNH_F_BADSTATE)) {
 735 +                               if (nh->nh_power > w) {
 736 +                                       w = nh->nh_power;
 737 +                                       sel = nhsel;
 738 +                               }
 739 +                       }
 740 +               } endfor_nexthops(fi);
 741 +               if (sel >= 0) {
 742 +                       spin_unlock_bh(&fib_multipath_lock);
 743 +                       res->nh_sel = sel;
 744 +                       return;
 745 +               }
 746 +               goto last_resort;
 747 +       }
 748 +
 749 +repeat:
 750         if (fi->fib_power <= 0) {
 751                 int power = 0;
 752                 change_nexthops(fi) {
 753 -                       if (!(nh->nh_flags&RTNH_F_DEAD)) {
 754 +                       if (!(nh->nh_flags&RTNH_F_BADSTATE)) {
 755                                 power += nh->nh_weight;
 756                                 nh->nh_power = nh->nh_weight;
 757                         }
 758                 } endfor_nexthops(fi);
 759                 fi->fib_power = power;
 760 -               if (power <= 0) {
 761 -                       spin_unlock_bh(&fib_multipath_lock);
 762 -                       /* Race condition: route has just become dead. */
 763 -                       res->nh_sel = 0;
 764 -                       return;
 765 -               }
 766 +               if (power <= 0)
 767 +                       goto last_resort;
 768         }
 769
 770
 771 @@ -1203,20 +1338,40 @@ void fib_select_multipath(const struct f
 772
 773         w = jiffies % fi->fib_power;
 774
 775 +       alive = 0;
 776         change_nexthops(fi) {
 777 -               if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
 778 +               if (!(nh->nh_flags&RTNH_F_BADSTATE) && nh->nh_power) {
 779                         if ((w -= nh->nh_power) <= 0) {
 780                                 nh->nh_power--;
 781                                 fi->fib_power--;
 782 -                               res->nh_sel = nhsel;
 783                                 spin_unlock_bh(&fib_multipath_lock);
 784 +                               res->nh_sel = nhsel;
 785                                 return;
 786                         }
 787 +                       alive = 1;
 788 +               }
 789 +       } endfor_nexthops(fi);
 790 +       if (alive) {
 791 +               fi->fib_power = 0;
 792 +               goto repeat;
 793 +       }
 794 +
 795 +last_resort:
 796 +
 797 +       for_nexthops(fi) {
 798 +               if (!(nh->nh_flags&RTNH_F_DEAD)) {
 799 +                       if (flp->oif && flp->oif != nh->nh_oif)
 800 +                               continue;
 801 +                       if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
 802 +                           nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
 803 +                               continue;
 804 +                       spin_unlock_bh(&fib_multipath_lock);
 805 +                       res->nh_sel = nhsel;
 806 +                       return;
 807                 }
 808         } endfor_nexthops(fi);
 809
 810         /* Race condition: route has just become dead. */
 811 -       res->nh_sel = 0;
 812         spin_unlock_bh(&fib_multipath_lock);
 813  }
 814  #endif
 815 diff -urp v2.6.27/linux/net/ipv4/fib_trie.c linux/net/ipv4/fib_trie.c
 816 --- v2.6.27/linux/net/ipv4/fib_trie.c   2008-10-11 12:46:16.000000000 +0300
 817 +++ linux/net/ipv4/fib_trie.c   2008-10-11 13:50:41.000000000 +0300
 818 @@ -1261,6 +1261,7 @@ static int fn_trie_insert(struct fib_tab
 819                         fi_drop = fa->fa_info;
 820                         new_fa->fa_tos = fa->fa_tos;
 821                         new_fa->fa_info = fi;
 822 +                       new_fa->fa_last_dflt = -1;
 823                         new_fa->fa_type = cfg->fc_type;
 824                         new_fa->fa_scope = cfg->fc_scope;
 825                         state = fa->fa_state;
 826 @@ -1301,6 +1302,7 @@ static int fn_trie_insert(struct fib_tab
 827         new_fa->fa_type = cfg->fc_type;
 828         new_fa->fa_scope = cfg->fc_scope;
 829         new_fa->fa_state = 0;
 830 +       new_fa->fa_last_dflt = -1;
 831         /*
 832          * Insert new entry to the list.
 833          */
 834 @@ -1802,24 +1804,31 @@ static void fn_trie_select_default(struc
 835                                    struct fib_result *res)
 836  {
 837         struct trie *t = (struct trie *) tb->tb_data;
 838 -       int order, last_idx;
 839 +       int order, last_idx, last_dflt, last_nhsel;
 840 +       struct fib_alias *first_fa = NULL;
 841         struct fib_info *fi = NULL;
 842         struct fib_info *last_resort;
 843         struct fib_alias *fa = NULL;
 844         struct list_head *fa_head;
 845         struct leaf *l;
 846 +       u32 key, mask;
 847
 848 +       last_dflt = -2;
 849 +       last_nhsel = 0;
 850         last_idx = -1;
 851         last_resort = NULL;
 852         order = -1;
 853
 854 +       mask = inet_make_mask(res->prefixlen);
 855 +       key = ntohl(flp->fl4_dst & mask);
 856 +
 857         rcu_read_lock();
 858
 859 -       l = fib_find_node(t, 0);
 860 +       l = fib_find_node(t, key);
 861         if (!l)
 862                 goto out;
 863
 864 -       fa_head = get_fa_head(l, 0);
 865 +       fa_head = get_fa_head(l, res->prefixlen);
 866         if (!fa_head)
 867                 goto out;
 868
 869 @@ -1833,39 +1842,52 @@ static void fn_trie_select_default(struc
 870                     fa->fa_type != RTN_UNICAST)
 871                         continue;
 872
 873 +               if (fa->fa_tos &&
 874 +                   fa->fa_tos != flp->fl4_tos)
 875 +                       continue;
 876                 if (next_fi->fib_priority > res->fi->fib_priority)
 877                         break;
 878 -               if (!next_fi->fib_nh[0].nh_gw ||
 879 -                   next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
 880 -                       continue;
 881                 fa->fa_state |= FA_S_ACCESSED;
 882
 883 -               if (fi == NULL) {
 884 -                       if (next_fi != res->fi)
 885 -                               break;
 886 -               } else if (!fib_detect_death(fi, order, &last_resort,
 887 -                                            &last_idx, tb->tb_default)) {
 888 +               if (!first_fa) {
 889 +                       last_dflt = fa->fa_last_dflt;
 890 +                       first_fa = fa;
 891 +               }
 892 +               if (fi && !fib_detect_death(fi, order, &last_resort,
 893 +                   &last_idx, &last_dflt, &last_nhsel, flp)) {
 894                         fib_result_assign(res, fi);
 895 -                       tb->tb_default = order;
 896 +                       first_fa->fa_last_dflt = order;
 897                         goto out;
 898                 }
 899                 fi = next_fi;
 900                 order++;
 901         }
 902         if (order <= 0 || fi == NULL) {
 903 -               tb->tb_default = -1;
 904 +               if (fi && fi->fib_nhs > 1 &&
 905 +                   fib_detect_death(fi, order, &last_resort, &last_idx,
 906 +                                    &last_dflt, &last_nhsel, flp) &&
 907 +                   last_resort == fi) {
 908 +                       read_lock_bh(&fib_nhflags_lock);
 909 +                       fi->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
 910 +                       read_unlock_bh(&fib_nhflags_lock);
 911 +               }
 912 +               if (first_fa) first_fa->fa_last_dflt = -1;
 913                 goto out;
 914         }
 915
 916         if (!fib_detect_death(fi, order, &last_resort, &last_idx,
 917 -                               tb->tb_default)) {
 918 +                               &last_dflt, &last_nhsel, flp)) {
 919                 fib_result_assign(res, fi);
 920 -               tb->tb_default = order;
 921 +               first_fa->fa_last_dflt = order;
 922                 goto out;
 923         }
 924 -       if (last_idx >= 0)
 925 +       if (last_idx >= 0) {
 926                 fib_result_assign(res, last_resort);
 927 -       tb->tb_default = last_idx;
 928 +               read_lock_bh(&fib_nhflags_lock);
 929 +               last_resort->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
 930 +               read_unlock_bh(&fib_nhflags_lock);
 931 +               first_fa->fa_last_dflt = last_idx;
 932 +       }
 933  out:
 934         rcu_read_unlock();
 935  }
 936 diff -urp v2.6.27/linux/net/ipv4/netfilter/ipt_MASQUERADE.c linux/net/ipv4/netfilter/ipt_MASQUERADE.c
 937 --- v2.6.27/linux/net/ipv4/netfilter/ipt_MASQUERADE.c   2008-10-11 12:46:16.000000000 +0300
 938 +++ linux/net/ipv4/netfilter/ipt_MASQUERADE.c   2008-10-11 13:51:37.000000000 +0300
 939 @@ -59,7 +59,7 @@ masquerade_tg(struct sk_buff *skb, const
 940         enum ip_conntrack_info ctinfo;
 941         struct nf_nat_range newrange;
 942         const struct nf_nat_multi_range_compat *mr;
 943 -       const struct rtable *rt;
 944 +       struct rtable *rt;
 945         __be32 newsrc;
 946
 947         NF_CT_ASSERT(hooknum == NF_INET_POST_ROUTING);
 948 @@ -77,13 +77,28 @@ masquerade_tg(struct sk_buff *skb, const
 949                 return NF_ACCEPT;
 950
 951         mr = targinfo;
 952 -       rt = skb->rtable;
 953 -       newsrc = inet_select_addr(out, rt->rt_gateway, RT_SCOPE_UNIVERSE);
 954 -       if (!newsrc) {
 955 -               printk("MASQUERADE: %s ate my IP address\n", out->name);
 956 -               return NF_DROP;
 957 +
 958 +       {
 959 +               struct flowi fl = { .nl_u = { .ip4_u =
 960 +                                             { .daddr = ip_hdr(skb)->daddr,
 961 +                                               .tos = (RT_TOS(ip_hdr(skb)->tos) |
 962 +                                                       RTO_CONN),
 963 +                                               .gw = skb->rtable->rt_gateway,
 964 +                                             } },
 965 +                                   .mark = skb->mark,
 966 +                                   .oif = out->ifindex };
 967 +               if (ip_route_output_key(dev_net(out), &rt, &fl) != 0) {
 968 +                       /* Funky routing can do this. */
 969 +                       if (net_ratelimit())
 970 +                               printk("MASQUERADE:"
 971 +                                      " No route: Rusty's brain broke!\n");
 972 +                       return NF_DROP;
 973 +               }
 974         }
 975
 976 +       newsrc = rt->rt_src;
 977 +       ip_rt_put(rt);
 978 +
 979         write_lock_bh(&masq_lock);
 980         nat->masq_index = out->ifindex;
 981         write_unlock_bh(&masq_lock);
 982 diff -urp v2.6.27/linux/net/ipv4/netfilter/nf_nat_core.c linux/net/ipv4/netfilter/nf_nat_core.c
 983 --- v2.6.27/linux/net/ipv4/netfilter/nf_nat_core.c      2008-10-11 12:46:16.000000000 +0300
 984 +++ linux/net/ipv4/netfilter/nf_nat_core.c      2008-10-11 13:51:37.000000000 +0300
 985 @@ -583,6 +583,52 @@ static struct nf_ct_ext_type nat_extend
 986         .flags          = NF_CT_EXT_F_PREALLOC,
 987  };
 988
 989 +unsigned int
 990 +ip_nat_route_input(unsigned int hooknum,
 991 +               struct sk_buff *skb,
 992 +               const struct net_device *in,
 993 +               const struct net_device *out,
 994 +               int (*okfn)(struct sk_buff *))
 995 +{
 996 +       struct iphdr *iph;
 997 +       struct nf_conn *conn;
 998 +       enum ip_conntrack_info ctinfo;
 999 +       enum ip_conntrack_dir dir;
1000 +       unsigned long statusbit;
1001 +       __be32 saddr;
1002 +
1003 +       if (!(conn = nf_ct_get(skb, &ctinfo)))
1004 +               return NF_ACCEPT;
1005 +
1006 +       if (!(conn->status & IPS_NAT_DONE_MASK))
1007 +               return NF_ACCEPT;
1008 +       dir = CTINFO2DIR(ctinfo);
1009 +       statusbit = IPS_SRC_NAT;
1010 +       if (dir == IP_CT_DIR_REPLY)
1011 +               statusbit ^= IPS_NAT_MASK;
1012 +       if (!(conn->status & statusbit))
1013 +               return NF_ACCEPT;
1014 +
1015 +       if (skb->dst)
1016 +               return NF_ACCEPT;
1017 +
1018 +       if (skb->len < sizeof(struct iphdr))
1019 +               return NF_ACCEPT;
1020 +
1021 +       /* use daddr in other direction as masquerade address (lsrc) */
1022 +       iph = ip_hdr(skb);
1023 +       saddr = conn->tuplehash[!dir].tuple.dst.u3.ip;
1024 +       if (saddr == iph->saddr)
1025 +               return NF_ACCEPT;
1026 +
1027 +       if (ip_route_input_lookup(skb, iph->daddr, iph->saddr, iph->tos,
1028 +           skb->dev, saddr))
1029 +               return NF_DROP;
1030 +
1031 +       return NF_ACCEPT;
1032 +}
1033 +EXPORT_SYMBOL_GPL(ip_nat_route_input);
1034 +
1035  static int __init nf_nat_init(void)
1036  {
1037         size_t i;
1038 diff -urp v2.6.27/linux/net/ipv4/netfilter/nf_nat_standalone.c linux/net/ipv4/netfilter/nf_nat_standalone.c
1039 --- v2.6.27/linux/net/ipv4/netfilter/nf_nat_standalone.c        2008-07-14 09:58:50.000000000 +0300
1040 +++ linux/net/ipv4/netfilter/nf_nat_standalone.c        2008-10-11 13:51:37.000000000 +0300
1041 @@ -256,6 +256,14 @@ static struct nf_hook_ops nf_nat_ops[] _
1042                 .hooknum        = NF_INET_PRE_ROUTING,
1043                 .priority       = NF_IP_PRI_NAT_DST,
1044         },
1045 +       /* Before routing, route before mangling */
1046 +       {
1047 +               .hook           = ip_nat_route_input,
1048 +               .owner          = THIS_MODULE,
1049 +               .pf             = PF_INET,
1050 +               .hooknum        = NF_INET_PRE_ROUTING,
1051 +               .priority       = NF_IP_PRI_LAST-1,
1052 +       },
1053         /* After packet filtering, change source */
1054         {
1055                 .hook           = nf_nat_out,
1056 diff -urp v2.6.27/linux/net/ipv4/route.c linux/net/ipv4/route.c
1057 --- v2.6.27/linux/net/ipv4/route.c      2008-10-11 12:46:16.000000000 +0300
1058 +++ linux/net/ipv4/route.c      2008-10-11 13:51:37.000000000 +0300
1059 @@ -1276,6 +1276,7 @@ void ip_rt_redirect(__be32 old_gw, __be3
1060
1061                                 /* Gateway is different ... */
1062                                 rt->rt_gateway          = new_gw;
1063 +                               if (rt->fl.fl4_gw) rt->fl.fl4_gw = new_gw;
1064
1065                                 /* Redirect received -> path was valid */
1066                                 dst_confirm(&rth->u.dst);
1067 @@ -1725,6 +1726,7 @@ static int ip_route_input_mc(struct sk_b
1068         rth->fl.fl4_tos = tos;
1069         rth->fl.mark    = skb->mark;
1070         rth->fl.fl4_src = saddr;
1071 +       rth->fl.fl4_lsrc = 0;
1072         rth->rt_src     = saddr;
1073  #ifdef CONFIG_NET_CLS_ROUTE
1074         rth->u.dst.tclassid = itag;
1075 @@ -1735,6 +1737,7 @@ static int ip_route_input_mc(struct sk_b
1076         dev_hold(rth->u.dst.dev);
1077         rth->idev       = in_dev_get(rth->u.dst.dev);
1078         rth->fl.oif     = 0;
1079 +       rth->fl.fl4_gw  = 0;
1080         rth->rt_gateway = daddr;
1081         rth->rt_spec_dst= spec_dst;
1082         rth->rt_genid   = rt_genid(dev_net(dev));
1083 @@ -1800,7 +1803,7 @@ static int __mkroute_input(struct sk_buf
1084                            struct fib_result *res,
1085                            struct in_device *in_dev,
1086                            __be32 daddr, __be32 saddr, u32 tos,
1087 -                          struct rtable **result)
1088 +                          __be32 lsrc, struct rtable **result)
1089  {
1090
1091         struct rtable *rth;
1092 @@ -1834,6 +1837,7 @@ static int __mkroute_input(struct sk_buf
1093                 flags |= RTCF_DIRECTSRC;
1094
1095         if (out_dev == in_dev && err &&
1096 +           !lsrc &&
1097             (IN_DEV_SHARED_MEDIA(out_dev) ||
1098              inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1099                 flags |= RTCF_DOREDIRECT;
1100 @@ -1867,6 +1871,7 @@ static int __mkroute_input(struct sk_buf
1101         rth->fl.mark    = skb->mark;
1102         rth->fl.fl4_src = saddr;
1103         rth->rt_src     = saddr;
1104 +       rth->fl.fl4_lsrc        = lsrc;
1105         rth->rt_gateway = daddr;
1106         rth->rt_iif     =
1107                 rth->fl.iif     = in_dev->dev->ifindex;
1108 @@ -1874,6 +1879,7 @@ static int __mkroute_input(struct sk_buf
1109         dev_hold(rth->u.dst.dev);
1110         rth->idev       = in_dev_get(rth->u.dst.dev);
1111         rth->fl.oif     = 0;
1112 +       rth->fl.fl4_gw  = 0;
1113         rth->rt_spec_dst= spec_dst;
1114
1115         rth->u.dst.input = ip_forward;
1116 @@ -1894,21 +1900,23 @@ static int __mkroute_input(struct sk_buf
1117
1118  static int ip_mkroute_input(struct sk_buff *skb,
1119                             struct fib_result *res,
1120 +                           struct net *net,
1121                             const struct flowi *fl,
1122                             struct in_device *in_dev,
1123 -                           __be32 daddr, __be32 saddr, u32 tos)
1124 +                           __be32 daddr, __be32 saddr, u32 tos, __be32 lsrc)
1125  {
1126         struct rtable* rth = NULL;
1127         int err;
1128         unsigned hash;
1129
1130 +       fib_select_default(net, fl, res);
1131  #ifdef CONFIG_IP_ROUTE_MULTIPATH
1132 -       if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
1133 +       if (res->fi && res->fi->fib_nhs > 1)
1134                 fib_select_multipath(fl, res);
1135  #endif
1136
1137         /* create a routing cache entry */
1138 -       err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
1139 +       err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, lsrc, &rth);
1140         if (err)
1141                 return err;
1142
1143 @@ -1929,18 +1937,19 @@ static int ip_mkroute_input(struct sk_bu
1144   */
1145
1146  static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1147 -                              u8 tos, struct net_device *dev)
1148 +                              u8 tos, struct net_device *dev, __be32 lsrc)
1149  {
1150         struct fib_result res;
1151         struct in_device *in_dev = in_dev_get(dev);
1152         struct flowi fl = { .nl_u = { .ip4_u =
1153                                       { .daddr = daddr,
1154 -                                       .saddr = saddr,
1155 +                                       .saddr = lsrc? : saddr,
1156                                         .tos = tos,
1157                                         .scope = RT_SCOPE_UNIVERSE,
1158                                       } },
1159                             .mark = skb->mark,
1160 -                           .iif = dev->ifindex };
1161 +                           .iif = lsrc?
1162 +                               dev_net(dev)->loopback_dev->ifindex : dev->ifindex };
1163         unsigned        flags = 0;
1164         u32             itag = 0;
1165         struct rtable * rth;
1166 @@ -1976,6 +1985,12 @@ static int ip_route_input_slow(struct sk
1167             ipv4_is_loopback(daddr))
1168                 goto martian_destination;
1169
1170 +       if (lsrc) {
1171 +               if (ipv4_is_multicast(lsrc) || ipv4_is_lbcast(lsrc) ||
1172 +                   ipv4_is_zeronet(lsrc) || ipv4_is_loopback(lsrc))
1173 +                       goto e_inval;
1174 +       }
1175 +
1176         /*
1177          *      Now we are ready to route packet.
1178          */
1179 @@ -1985,6 +2000,8 @@ static int ip_route_input_slow(struct sk
1180                 goto no_route;
1181         }
1182         free_res = 1;
1183 +       fl.iif = dev->ifindex;
1184 +       fl.fl4_src = saddr;
1185
1186         RT_CACHE_STAT_INC(in_slow_tot);
1187
1188 @@ -2009,7 +2026,7 @@ static int ip_route_input_slow(struct sk
1189         if (res.type != RTN_UNICAST)
1190                 goto martian_destination;
1191
1192 -       err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
1193 +       err = ip_mkroute_input(skb, &res, net, &fl, in_dev, daddr, saddr, tos, lsrc);
1194  done:
1195         in_dev_put(in_dev);
1196         if (free_res)
1197 @@ -2019,6 +2036,8 @@ out:      return err;
1198  brd_input:
1199         if (skb->protocol != htons(ETH_P_IP))
1200                 goto e_inval;
1201 +       if (lsrc)
1202 +               goto e_inval;
1203
1204         if (ipv4_is_zeronet(saddr))
1205                 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
1206 @@ -2060,6 +2079,7 @@ local_input:
1207         rth->u.dst.dev  = net->loopback_dev;
1208         dev_hold(rth->u.dst.dev);
1209         rth->idev       = in_dev_get(rth->u.dst.dev);
1210 +       rth->fl.fl4_gw  = 0;
1211         rth->rt_gateway = daddr;
1212         rth->rt_spec_dst= spec_dst;
1213         rth->u.dst.input= ip_local_deliver;
1214 @@ -2111,8 +2131,9 @@ martian_source:
1215         goto e_inval;
1216  }
1217
1218 -int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1219 -                  u8 tos, struct net_device *dev)
1220 +static inline int
1221 +ip_route_input_cached(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1222 +                  u8 tos, struct net_device *dev, __be32 lsrc)
1223  {
1224         struct rtable * rth;
1225         unsigned        hash;
1226 @@ -2129,6 +2150,7 @@ int ip_route_input(struct sk_buff *skb,
1227                 if (((rth->fl.fl4_dst ^ daddr) |
1228                      (rth->fl.fl4_src ^ saddr) |
1229                      (rth->fl.iif ^ iif) |
1230 +                    (rth->fl.fl4_lsrc ^ lsrc) |
1231                      rth->fl.oif |
1232                      (rth->fl.fl4_tos ^ tos)) == 0 &&
1233                     rth->fl.mark == skb->mark &&
1234 @@ -2176,7 +2198,19 @@ int ip_route_input(struct sk_buff *skb,
1235                 rcu_read_unlock();
1236                 return -EINVAL;
1237         }
1238 -       return ip_route_input_slow(skb, daddr, saddr, tos, dev);
1239 +       return ip_route_input_slow(skb, daddr, saddr, tos, dev, lsrc);
1240 +}
1241 +
1242 +int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1243 +                  u8 tos, struct net_device *dev)
1244 +{
1245 +       return ip_route_input_cached(skb, daddr, saddr, tos, dev, 0);
1246 +}
1247 +
1248 +int ip_route_input_lookup(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1249 +                         u8 tos, struct net_device *dev, __be32 lsrc)
1250 +{
1251 +       return ip_route_input_cached(skb, daddr, saddr, tos, dev, lsrc);
1252  }
1253
1254  static int __mkroute_output(struct rtable **result,
1255 @@ -2248,6 +2282,7 @@ static int __mkroute_output(struct rtabl
1256         rth->fl.fl4_tos = tos;
1257         rth->fl.fl4_src = oldflp->fl4_src;
1258         rth->fl.oif     = oldflp->oif;
1259 +       rth->fl.fl4_gw  = oldflp->fl4_gw;
1260         rth->fl.mark    = oldflp->mark;
1261         rth->rt_dst     = fl->fl4_dst;
1262         rth->rt_src     = fl->fl4_src;
1263 @@ -2329,6 +2364,7 @@ static int ip_route_output_slow(struct n
1264         struct flowi fl = { .nl_u = { .ip4_u =
1265                                       { .daddr = oldflp->fl4_dst,
1266                                         .saddr = oldflp->fl4_src,
1267 +                                       .gw = oldflp->fl4_gw,
1268                                         .tos = tos & IPTOS_RT_MASK,
1269                                         .scope = ((tos & RTO_ONLINK) ?
1270                                                   RT_SCOPE_LINK :
1271 @@ -2434,6 +2470,7 @@ static int ip_route_output_slow(struct n
1272                 dev_out = net->loopback_dev;
1273                 dev_hold(dev_out);
1274                 fl.oif = net->loopback_dev->ifindex;
1275 +               fl.fl4_gw = 0;
1276                 res.type = RTN_LOCAL;
1277                 flags |= RTCF_LOCAL;
1278                 goto make_route;
1279 @@ -2441,7 +2478,7 @@ static int ip_route_output_slow(struct n
1280
1281         if (fib_lookup(net, &fl, &res)) {
1282                 res.fi = NULL;
1283 -               if (oldflp->oif) {
1284 +               if (oldflp->oif && dev_out->flags & IFF_UP) {
1285                         /* Apparently, routing tables are wrong. Assume,
1286                            that the destination is on link.
1287
1288 @@ -2481,6 +2518,7 @@ static int ip_route_output_slow(struct n
1289                 dev_out = net->loopback_dev;
1290                 dev_hold(dev_out);
1291                 fl.oif = dev_out->ifindex;
1292 +               fl.fl4_gw = 0;
1293                 if (res.fi)
1294                         fib_info_put(res.fi);
1295                 res.fi = NULL;
1296 @@ -2488,13 +2526,12 @@ static int ip_route_output_slow(struct n
1297                 goto make_route;
1298         }
1299
1300 +       if (res.type == RTN_UNICAST)
1301 +               fib_select_default(net, &fl, &res);
1302  #ifdef CONFIG_IP_ROUTE_MULTIPATH
1303 -       if (res.fi->fib_nhs > 1 && fl.oif == 0)
1304 +       if (res.fi->fib_nhs > 1)
1305                 fib_select_multipath(&fl, &res);
1306 -       else
1307  #endif
1308 -       if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
1309 -               fib_select_default(net, &fl, &res);
1310
1311         if (!fl.fl4_src)
1312                 fl.fl4_src = FIB_RES_PREFSRC(res);
1313 @@ -2532,6 +2569,7 @@ int __ip_route_output_key(struct net *ne
1314                     rth->fl.fl4_src == flp->fl4_src &&
1315                     rth->fl.iif == 0 &&
1316                     rth->fl.oif == flp->oif &&
1317 +                   rth->fl.fl4_gw == flp->fl4_gw &&
1318                     rth->fl.mark == flp->mark &&
1319                     !((rth->fl.fl4_tos ^ flp->fl4_tos) &
1320                             (IPTOS_RT_MASK | RTO_ONLINK)) &&
1321 @@ -3310,3 +3348,4 @@ void __init ip_static_sysctl_init(void)
1322  EXPORT_SYMBOL(__ip_select_ident);
1323  EXPORT_SYMBOL(ip_route_input);
1324  EXPORT_SYMBOL(ip_route_output_key);
1325 +EXPORT_SYMBOL(ip_route_input_lookup);