target/linux/generic-2.6/patches/108-netfilter_route.patch

   1 diff -u'rNF^function' linux-2.6.16.7/include/linux/netfilter_ipv4/ipt_ROUTE.h linux-2.6.16.7-ROUTE/include/linux/netfilter_ipv4/ipt_ROUTE.h
   2 --- linux-2.6.16.7/include/linux/netfilter_ipv4/ipt_ROUTE.h     1970-01-01 01:00:00.000000000 +0100
   3 +++ linux-2.6.16.7-ROUTE/include/linux/netfilter_ipv4/ipt_ROUTE.h       2006-06-14 16:40:49.000000000 +0200
   4 @@ -0,0 +1,23 @@
   5 +/* Header file for iptables ipt_ROUTE target
   6 + *
   7 + * (C) 2002 by Cédric de Launois <delaunois@info.ucl.ac.be>
   8 + *
   9 + * This software is distributed under GNU GPL v2, 1991
  10 + */
  11 +#ifndef _IPT_ROUTE_H_target
  12 +#define _IPT_ROUTE_H_target
  13 +
  14 +#define IPT_ROUTE_IFNAMSIZ 16
  15 +
  16 +struct ipt_route_target_info {
  17 +       char      oif[IPT_ROUTE_IFNAMSIZ];      /* Output Interface Name */
  18 +       char      iif[IPT_ROUTE_IFNAMSIZ];      /* Input Interface Name  */
  19 +       u_int32_t gw;                           /* IP address of gateway */
  20 +       u_int8_t  flags;
  21 +};
  22 +
  23 +/* Values for "flags" field */
  24 +#define IPT_ROUTE_CONTINUE        0x01
  25 +#define IPT_ROUTE_TEE             0x02
  26 +
  27 +#endif /*_IPT_ROUTE_H_target*/
  28 diff -u'rNF^function' linux-2.6.16.7/include/linux/netfilter_ipv6/ip6t_ROUTE.h linux-2.6.16.7-ROUTE/include/linux/netfilter_ipv6/ip6t_ROUTE.h
  29 --- linux-2.6.16.7/include/linux/netfilter_ipv6/ip6t_ROUTE.h    1970-01-01 01:00:00.000000000 +0100
  30 +++ linux-2.6.16.7-ROUTE/include/linux/netfilter_ipv6/ip6t_ROUTE.h      2006-06-14 16:41:08.000000000 +0200
  31 @@ -0,0 +1,23 @@
  32 +/* Header file for iptables ip6t_ROUTE target
  33 + *
  34 + * (C) 2003 by Cédric de Launois <delaunois@info.ucl.ac.be>
  35 + *
  36 + * This software is distributed under GNU GPL v2, 1991
  37 + */
  38 +#ifndef _IPT_ROUTE_H_target
  39 +#define _IPT_ROUTE_H_target
  40 +
  41 +#define IP6T_ROUTE_IFNAMSIZ 16
  42 +
  43 +struct ip6t_route_target_info {
  44 +       char      oif[IP6T_ROUTE_IFNAMSIZ];     /* Output Interface Name */
  45 +       char      iif[IP6T_ROUTE_IFNAMSIZ];     /* Input Interface Name  */
  46 +       u_int32_t gw[4];                        /* IPv6 address of gateway */
  47 +       u_int8_t  flags;
  48 +};
  49 +
  50 +/* Values for "flags" field */
  51 +#define IP6T_ROUTE_CONTINUE        0x01
  52 +#define IP6T_ROUTE_TEE             0x02
  53 +
  54 +#endif /*_IP6T_ROUTE_H_target*/
  55 diff -u'rNF^function' linux-2.6.16.7/net/ipv4/netfilter/Kconfig linux-2.6.16.7-ROUTE/net/ipv4/netfilter/Kconfig
  56 --- linux-2.6.16.7/net/ipv4/netfilter/Kconfig   2006-06-14 16:05:44.000000000 +0200
  57 +++ linux-2.6.16.7-ROUTE/net/ipv4/netfilter/Kconfig     2006-06-14 16:46:40.000000000 +0200
  58 @@ -491,6 +491,23 @@
  59
  60           To compile it as a module, choose M here.  If unsure, say N.
  61
  62 +config IP_NF_TARGET_ROUTE
  63 +        tristate  'ROUTE target support'
  64 +        depends on IP_NF_MANGLE
  65 +        help
  66 +          This option adds a `ROUTE' target, which enables you to setup unusual
  67 +          routes. For example, the ROUTE lets you route a received packet through
  68 +          an interface or towards a host, even if the regular destination of the
  69 +          packet is the router itself. The ROUTE target is also able to change the
  70 +          incoming interface of a packet.
  71 +
  72 +          The target can be or not a final target. It has to be used inside the
  73 +          mangle table.
  74 +
  75 +          If you want to compile it as a module, say M here and read
  76 +          Documentation/modules.txt.  The module will be called ipt_ROUTE.o.
  77 +          If unsure, say `N'.
  78 +
  79  config IP_NF_TARGET_NETMAP
  80         tristate "NETMAP target support"
  81         depends on IP_NF_NAT
  82 diff -u'rNF^function' linux-2.6.16.7/net/ipv4/netfilter/Makefile linux-2.6.16.7-ROUTE/net/ipv4/netfilter/Makefile
  83 --- linux-2.6.16.7/net/ipv4/netfilter/Makefile  2006-06-14 16:05:44.000000000 +0200
  84 +++ linux-2.6.16.7-ROUTE/net/ipv4/netfilter/Makefile    2006-06-14 16:44:02.000000000 +0200
  85 @@ -74,6 +74,7 @@
  86  obj-$(CONFIG_IP_NF_TARGET_IMQ) += ipt_IMQ.o
  87  obj-$(CONFIG_IP_NF_TARGET_MASQUERADE) += ipt_MASQUERADE.o
  88  obj-$(CONFIG_IP_NF_TARGET_REDIRECT) += ipt_REDIRECT.o
  89 +obj-$(CONFIG_IP_NF_TARGET_ROUTE) += ipt_ROUTE.o
  90  obj-$(CONFIG_IP_NF_TARGET_NETMAP) += ipt_NETMAP.o
  91  obj-$(CONFIG_IP_NF_TARGET_SAME) += ipt_SAME.o
  92  obj-$(CONFIG_IP_NF_NAT_SNMP_BASIC) += ip_nat_snmp_basic.o
  93 diff -u'rNF^function' linux-2.6.16.7/net/ipv4/netfilter/ipt_ROUTE.c linux-2.6.16.7-ROUTE/net/ipv4/netfilter/ipt_ROUTE.c
  94 --- linux-2.6.16.7/net/ipv4/netfilter/ipt_ROUTE.c       1970-01-01 01:00:00.000000000 +0100
  95 +++ linux-2.6.16.7-ROUTE/net/ipv4/netfilter/ipt_ROUTE.c 2006-06-14 16:42:23.000000000 +0200
  96 @@ -0,0 +1,461 @@
  97 +/*
  98 + * This implements the ROUTE target, which enables you to setup unusual
  99 + * routes not supported by the standard kernel routing table.
 100 + *
 101 + * Copyright (C) 2002 Cedric de Launois <delaunois@info.ucl.ac.be>
 102 + *
 103 + * v 1.11 2004/11/23
 104 + *
 105 + * This software is distributed under GNU GPL v2, 1991
 106 + */
 107 +
 108 +#include <linux/module.h>
 109 +#include <linux/skbuff.h>
 110 +#include <linux/ip.h>
 111 +#include <linux/netfilter_ipv4/ip_tables.h>
 112 +#include <linux/netfilter_ipv4/ip_conntrack.h>
 113 +#include <linux/netfilter_ipv4/ipt_ROUTE.h>
 114 +#include <linux/netdevice.h>
 115 +#include <linux/route.h>
 116 +#include <linux/if_arp.h>
 117 +#include <net/ip.h>
 118 +#include <net/route.h>
 119 +#include <net/icmp.h>
 120 +#include <net/checksum.h>
 121 +
 122 +#if 0
 123 +#define DEBUGP printk
 124 +#else
 125 +#define DEBUGP(format, args...)
 126 +#endif
 127 +
 128 +MODULE_LICENSE("GPL");
 129 +MODULE_AUTHOR("Cedric de Launois <delaunois@info.ucl.ac.be>");
 130 +MODULE_DESCRIPTION("iptables ROUTE target module");
 131 +
 132 +/* Try to route the packet according to the routing keys specified in
 133 + * route_info. Keys are :
 134 + *  - ifindex :
 135 + *      0 if no oif preferred,
 136 + *      otherwise set to the index of the desired oif
 137 + *  - route_info->gw :
 138 + *      0 if no gateway specified,
 139 + *      otherwise set to the next host to which the pkt must be routed
 140 + * If success, skb->dev is the output device to which the packet must
 141 + * be sent and skb->dst is not NULL
 142 + *
 143 + * RETURN: -1 if an error occured
 144 + *          1 if the packet was succesfully routed to the
 145 + *            destination desired
 146 + *          0 if the kernel routing table could not route the packet
 147 + *            according to the keys specified
 148 + */
 149 +static int route(struct sk_buff *skb,
 150 +                unsigned int ifindex,
 151 +                const struct ipt_route_target_info *route_info)
 152 +{
 153 +       int err;
 154 +       struct rtable *rt;
 155 +       struct iphdr *iph = skb->nh.iph;
 156 +       struct flowi fl = {
 157 +               .oif = ifindex,
 158 +               .nl_u = {
 159 +                       .ip4_u = {
 160 +                               .daddr = iph->daddr,
 161 +                               .saddr = 0,
 162 +                               .tos = RT_TOS(iph->tos),
 163 +                               .scope = RT_SCOPE_UNIVERSE,
 164 +                       }
 165 +               }
 166 +       };
 167 +
 168 +       /* The destination address may be overloaded by the target */
 169 +       if (route_info->gw)
 170 +               fl.fl4_dst = route_info->gw;
 171 +
 172 +       /* Trying to route the packet using the standard routing table. */
 173 +       if ((err = ip_route_output_key(&rt, &fl))) {
 174 +               if (net_ratelimit())
 175 +                       DEBUGP("ipt_ROUTE: couldn't route pkt (err: %i)",err);
 176 +               return -1;
 177 +       }
 178 +
 179 +       /* Drop old route. */
 180 +       dst_release(skb->dst);
 181 +       skb->dst = NULL;
 182 +
 183 +       /* Success if no oif specified or if the oif correspond to the
 184 +        * one desired */
 185 +       if (!ifindex || rt->u.dst.dev->ifindex == ifindex) {
 186 +               skb->dst = &rt->u.dst;
 187 +               skb->dev = skb->dst->dev;
 188 +               skb->protocol = htons(ETH_P_IP);
 189 +               return 1;
 190 +       }
 191 +
 192 +       /* The interface selected by the routing table is not the one
 193 +        * specified by the user. This may happen because the dst address
 194 +        * is one of our own addresses.
 195 +        */
 196 +       if (net_ratelimit())
 197 +               DEBUGP("ipt_ROUTE: failed to route as desired gw=%u.%u.%u.%u oif=%i (got oif=%i)\n",
 198 +                      NIPQUAD(route_info->gw), ifindex, rt->u.dst.dev->ifindex);
 199 +
 200 +       return 0;
 201 +}
 202 +
 203 +
 204 +/* Stolen from ip_finish_output2
 205 + * PRE : skb->dev is set to the device we are leaving by
 206 + *       skb->dst is not NULL
 207 + * POST: the packet is sent with the link layer header pushed
 208 + *       the packet is destroyed
 209 + */
 210 +static void ip_direct_send(struct sk_buff *skb)
 211 +{
 212 +       struct dst_entry *dst = skb->dst;
 213 +       struct hh_cache *hh = dst->hh;
 214 +       struct net_device *dev = dst->dev;
 215 +       int hh_len = LL_RESERVED_SPACE(dev);
 216 +
 217 +       /* Be paranoid, rather than too clever. */
 218 +       if (unlikely(skb_headroom(skb) < hh_len && dev->hard_header)) {
 219 +               struct sk_buff *skb2;
 220 +
 221 +               skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
 222 +               if (skb2 == NULL) {
 223 +                       kfree_skb(skb);
 224 +                       return;
 225 +               }
 226 +               if (skb->sk)
 227 +                       skb_set_owner_w(skb2, skb->sk);
 228 +               kfree_skb(skb);
 229 +               skb = skb2;
 230 +       }
 231 +
 232 +       if (hh) {
 233 +               int hh_alen;
 234 +
 235 +               read_lock_bh(&hh->hh_lock);
 236 +               hh_alen = HH_DATA_ALIGN(hh->hh_len);
 237 +               memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
 238 +               read_unlock_bh(&hh->hh_lock);
 239 +               skb_push(skb, hh->hh_len);
 240 +               hh->hh_output(skb);
 241 +       } else if (dst->neighbour)
 242 +               dst->neighbour->output(skb);
 243 +       else {
 244 +               if (net_ratelimit())
 245 +                       DEBUGP(KERN_DEBUG "ipt_ROUTE: no hdr & no neighbour cache!\n");
 246 +               kfree_skb(skb);
 247 +       }
 248 +}
 249 +
 250 +
 251 +/* PRE : skb->dev is set to the device we are leaving by
 252 + * POST: - the packet is directly sent to the skb->dev device, without
 253 + *         pushing the link layer header.
 254 + *       - the packet is destroyed
 255 + */
 256 +static inline int dev_direct_send(struct sk_buff *skb)
 257 +{
 258 +       return dev_queue_xmit(skb);
 259 +}
 260 +
 261 +
 262 +static unsigned int route_oif(const struct ipt_route_target_info *route_info,
 263 +                             struct sk_buff *skb)
 264 +{
 265 +       unsigned int ifindex = 0;
 266 +       struct net_device *dev_out = NULL;
 267 +
 268 +       /* The user set the interface name to use.
 269 +        * Getting the current interface index.
 270 +        */
 271 +       if ((dev_out = dev_get_by_name(route_info->oif))) {
 272 +               ifindex = dev_out->ifindex;
 273 +       } else {
 274 +               /* Unknown interface name : packet dropped */
 275 +               if (net_ratelimit())
 276 +                       DEBUGP("ipt_ROUTE: oif interface %s not found\n", route_info->oif);
 277 +               return NF_DROP;
 278 +       }
 279 +
 280 +       /* Trying the standard way of routing packets */
 281 +       switch (route(skb, ifindex, route_info)) {
 282 +       case 1:
 283 +               dev_put(dev_out);
 284 +               if (route_info->flags & IPT_ROUTE_CONTINUE)
 285 +                       return IPT_CONTINUE;
 286 +
 287 +               ip_direct_send(skb);
 288 +               return NF_STOLEN;
 289 +
 290 +       case 0:
 291 +               /* Failed to send to oif. Trying the hard way */
 292 +               if (route_info->flags & IPT_ROUTE_CONTINUE)
 293 +                       return NF_DROP;
 294 +
 295 +               if (net_ratelimit())
 296 +                       DEBUGP("ipt_ROUTE: forcing the use of %i\n",
 297 +                              ifindex);
 298 +
 299 +               /* We have to force the use of an interface.
 300 +                * This interface must be a tunnel interface since
 301 +                * otherwise we can't guess the hw address for
 302 +                * the packet. For a tunnel interface, no hw address
 303 +                * is needed.
 304 +                */
 305 +               if ((dev_out->type != ARPHRD_TUNNEL)
 306 +                   && (dev_out->type != ARPHRD_IPGRE)) {
 307 +                       if (net_ratelimit())
 308 +                               DEBUGP("ipt_ROUTE: can't guess the hw addr !\n");
 309 +                       dev_put(dev_out);
 310 +                       return NF_DROP;
 311 +               }
 312 +
 313 +               /* Send the packet. This will also free skb
 314 +                * Do not go through the POST_ROUTING hook because
 315 +                * skb->dst is not set and because it will probably
 316 +                * get confused by the destination IP address.
 317 +                */
 318 +               skb->dev = dev_out;
 319 +               dev_direct_send(skb);
 320 +               dev_put(dev_out);
 321 +               return NF_STOLEN;
 322 +
 323 +       default:
 324 +               /* Unexpected error */
 325 +               dev_put(dev_out);
 326 +               return NF_DROP;
 327 +       }
 328 +}
 329 +
 330 +
 331 +static unsigned int route_iif(const struct ipt_route_target_info *route_info,
 332 +                             struct sk_buff *skb)
 333 +{
 334 +       struct net_device *dev_in = NULL;
 335 +
 336 +       /* Getting the current interface index. */
 337 +       if (!(dev_in = dev_get_by_name(route_info->iif))) {
 338 +               if (net_ratelimit())
 339 +                       DEBUGP("ipt_ROUTE: iif interface %s not found\n", route_info->iif);
 340 +               return NF_DROP;
 341 +       }
 342 +
 343 +       skb->dev = dev_in;
 344 +       dst_release(skb->dst);
 345 +       skb->dst = NULL;
 346 +
 347 +       netif_rx(skb);
 348 +       dev_put(dev_in);
 349 +       return NF_STOLEN;
 350 +}
 351 +
 352 +
 353 +static unsigned int route_gw(const struct ipt_route_target_info *route_info,
 354 +                            struct sk_buff *skb)
 355 +{
 356 +       if (route(skb, 0, route_info)!=1)
 357 +               return NF_DROP;
 358 +
 359 +       if (route_info->flags & IPT_ROUTE_CONTINUE)
 360 +               return IPT_CONTINUE;
 361 +
 362 +       ip_direct_send(skb);
 363 +       return NF_STOLEN;
 364 +}
 365 +
 366 +
 367 +/* To detect and deter routed packet loopback when using the --tee option,
 368 + * we take a page out of the raw.patch book: on the copied skb, we set up
 369 + * a fake ->nfct entry, pointing to the local &route_tee_track. We skip
 370 + * routing packets when we see they already have that ->nfct.
 371 + */
 372 +
 373 +static struct ip_conntrack route_tee_track;
 374 +
 375 +static unsigned int ipt_route_target(struct sk_buff **pskb,
 376 +                                    const struct net_device *in,
 377 +                                    const struct net_device *out,
 378 +                                    unsigned int hooknum,
 379 +                                    const void *targinfo,
 380 +                                    void *userinfo)
 381 +{
 382 +       const struct ipt_route_target_info *route_info = targinfo;
 383 +       struct sk_buff *skb = *pskb;
 384 +       unsigned int res;
 385 +
 386 +       if (skb->nfct == &route_tee_track.ct_general) {
 387 +               /* Loopback - a packet we already routed, is to be
 388 +                * routed another time. Avoid that, now.
 389 +                */
 390 +               if (net_ratelimit())
 391 +                       DEBUGP(KERN_DEBUG "ipt_ROUTE: loopback - DROP!\n");
 392 +               return NF_DROP;
 393 +       }
 394 +
 395 +       /* If we are at PREROUTING or INPUT hook
 396 +        * the TTL isn't decreased by the IP stack
 397 +        */
 398 +       if (hooknum == NF_IP_PRE_ROUTING ||
 399 +           hooknum == NF_IP_LOCAL_IN) {
 400 +
 401 +               struct iphdr *iph = skb->nh.iph;
 402 +
 403 +               if (iph->ttl <= 1) {
 404 +                       struct rtable *rt;
 405 +                       struct flowi fl = {
 406 +                               .oif = 0,
 407 +                               .nl_u = {
 408 +                                       .ip4_u = {
 409 +                                               .daddr = iph->daddr,
 410 +                                               .saddr = iph->saddr,
 411 +                                               .tos = RT_TOS(iph->tos),
 412 +                                               .scope = ((iph->tos & RTO_ONLINK) ?
 413 +                                                         RT_SCOPE_LINK :
 414 +                                                         RT_SCOPE_UNIVERSE)
 415 +                                       }
 416 +                               }
 417 +                       };
 418 +
 419 +                       if (ip_route_output_key(&rt, &fl)) {
 420 +                               return NF_DROP;
 421 +                       }
 422 +
 423 +                       if (skb->dev == rt->u.dst.dev) {
 424 +                               /* Drop old route. */
 425 +                               dst_release(skb->dst);
 426 +                               skb->dst = &rt->u.dst;
 427 +
 428 +                               /* this will traverse normal stack, and
 429 +                                * thus call conntrack on the icmp packet */
 430 +                               icmp_send(skb, ICMP_TIME_EXCEEDED,
 431 +                                         ICMP_EXC_TTL, 0);
 432 +                       }
 433 +
 434 +                       return NF_DROP;
 435 +               }
 436 +
 437 +               /*
 438 +                * If we are at INPUT the checksum must be recalculated since
 439 +                * the length could change as the result of a defragmentation.
 440 +                */
 441 +               if(hooknum == NF_IP_LOCAL_IN) {
 442 +                       iph->ttl = iph->ttl - 1;
 443 +                       iph->check = 0;
 444 +                       iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
 445 +               } else {
 446 +                       ip_decrease_ttl(iph);
 447 +               }
 448 +       }
 449 +
 450 +       if ((route_info->flags & IPT_ROUTE_TEE)) {
 451 +               /*
 452 +                * Copy the *pskb, and route the copy. Will later return
 453 +                * IPT_CONTINUE for the original skb, which should continue
 454 +                * on its way as if nothing happened. The copy should be
 455 +                * independantly delivered to the ROUTE --gw.
 456 +                */
 457 +               skb = skb_copy(*pskb, GFP_ATOMIC);
 458 +               if (!skb) {
 459 +                       if (net_ratelimit())
 460 +                               DEBUGP(KERN_DEBUG "ipt_ROUTE: copy failed!\n");
 461 +                       return IPT_CONTINUE;
 462 +               }
 463 +       }
 464 +
 465 +       /* Tell conntrack to forget this packet since it may get confused
 466 +        * when a packet is leaving with dst address == our address.
 467 +        * Good idea ? Dunno. Need advice.
 468 +        *
 469 +        * NEW: mark the skb with our &route_tee_track, so we avoid looping
 470 +        * on any already routed packet.
 471 +        */
 472 +       if (!(route_info->flags & IPT_ROUTE_CONTINUE)) {
 473 +               nf_conntrack_put(skb->nfct);
 474 +               skb->nfct = &route_tee_track.ct_general;
 475 +               skb->nfctinfo = IP_CT_NEW;
 476 +               nf_conntrack_get(skb->nfct);
 477 +       }
 478 +
 479 +       if (route_info->oif[0] != '\0') {
 480 +               res = route_oif(route_info, skb);
 481 +       } else if (route_info->iif[0] != '\0') {
 482 +               res = route_iif(route_info, skb);
 483 +       } else if (route_info->gw) {
 484 +               res = route_gw(route_info, skb);
 485 +       } else {
 486 +               if (net_ratelimit())
 487 +                       DEBUGP(KERN_DEBUG "ipt_ROUTE: no parameter !\n");
 488 +               res = IPT_CONTINUE;
 489 +       }
 490 +
 491 +       if ((route_info->flags & IPT_ROUTE_TEE))
 492 +               res = IPT_CONTINUE;
 493 +
 494 +       return res;
 495 +}
 496 +
 497 +
 498 +static int ipt_route_checkentry(const char *tablename,
 499 +                               const void *e,
 500 +                               void *targinfo,
 501 +                               unsigned int targinfosize,
 502 +                               unsigned int hook_mask)
 503 +{
 504 +       if (strcmp(tablename, "mangle") != 0) {
 505 +               printk("ipt_ROUTE: bad table `%s', use the `mangle' table.\n",
 506 +                      tablename);
 507 +               return 0;
 508 +       }
 509 +
 510 +       if (hook_mask & ~(  (1 << NF_IP_PRE_ROUTING)
 511 +                           | (1 << NF_IP_LOCAL_IN)
 512 +                           | (1 << NF_IP_FORWARD)
 513 +                           | (1 << NF_IP_LOCAL_OUT)
 514 +                           | (1 << NF_IP_POST_ROUTING))) {
 515 +               printk("ipt_ROUTE: bad hook\n");
 516 +               return 0;
 517 +       }
 518 +
 519 +       if (targinfosize != IPT_ALIGN(sizeof(struct ipt_route_target_info))) {
 520 +               printk(KERN_WARNING "ipt_ROUTE: targinfosize %u != %Zu\n",
 521 +                      targinfosize,
 522 +                      IPT_ALIGN(sizeof(struct ipt_route_target_info)));
 523 +               return 0;
 524 +       }
 525 +
 526 +       return 1;
 527 +}
 528 +
 529 +
 530 +static struct ipt_target ipt_route_reg = {
 531 +       .name = "ROUTE",
 532 +       .target = ipt_route_target,
 533 +       .checkentry = ipt_route_checkentry,
 534 +       .me = THIS_MODULE,
 535 +};
 536 +
 537 +static int __init init(void)
 538 +{
 539 +       /* Set up fake conntrack (stolen from raw.patch):
 540 +           - to never be deleted, not in any hashes */
 541 +       atomic_set(&route_tee_track.ct_general.use, 1);
 542 +       /*  - and look it like as a confirmed connection */
 543 +       set_bit(IPS_CONFIRMED_BIT, &route_tee_track.status);
 544 +       /* Initialize fake conntrack so that NAT will skip it */
 545 +       route_tee_track.status |= IPS_NAT_DONE_MASK;
 546 +
 547 +       return ipt_register_target(&ipt_route_reg);
 548 +}
 549 +
 550 +
 551 +static void __exit fini(void)
 552 +{
 553 +       ipt_unregister_target(&ipt_route_reg);
 554 +}
 555 +
 556 +module_init(init);
 557 +module_exit(fini);
 558 diff -u'rNF^function' linux-2.6.16.7/net/ipv6/ipv6_syms.c linux-2.6.16.7-ROUTE/net/ipv6/ipv6_syms.c
 559 --- linux-2.6.16.7/net/ipv6/ipv6_syms.c 2006-04-17 23:53:25.000000000 +0200
 560 +++ linux-2.6.16.7-ROUTE/net/ipv6/ipv6_syms.c   2006-06-14 17:02:32.000000000 +0200
 561 @@ -12,6 +12,7 @@
 562  EXPORT_SYMBOL(icmpv6_statistics);
 563  EXPORT_SYMBOL(icmpv6_err_convert);
 564  EXPORT_SYMBOL(ndisc_mc_map);
 565 +EXPORT_SYMBOL(nd_tbl);
 566  EXPORT_SYMBOL(register_inet6addr_notifier);
 567  EXPORT_SYMBOL(unregister_inet6addr_notifier);
 568  EXPORT_SYMBOL(ip6_route_output);
 569 diff -u'rNF^function' linux-2.6.16.7/net/ipv6/netfilter/Kconfig linux-2.6.16.7-ROUTE/net/ipv6/netfilter/Kconfig
 570 --- linux-2.6.16.7/net/ipv6/netfilter/Kconfig   2006-06-14 16:05:44.000000000 +0200
 571 +++ linux-2.6.16.7-ROUTE/net/ipv6/netfilter/Kconfig     2006-06-14 16:45:45.000000000 +0200
 572 @@ -182,6 +182,19 @@
 573
 574           To compile it as a module, choose M here.  If unsure, say N.
 575
 576 +config IP6_NF_TARGET_ROUTE
 577 +        tristate '    ROUTE target support'
 578 +        depends on IP6_NF_MANGLE
 579 +        help
 580 +          This option adds a `ROUTE' target, which enables you to setup unusual
 581 +          routes. The ROUTE target is also able to change the incoming interface
 582 +          of a packet.
 583 +
 584 +          The target can be or not a final target. It has to be used inside the
 585 +          mangle table.
 586 +
 587 +          Not working as a module.
 588 +
 589  config IP6_NF_MANGLE
 590         tristate "Packet mangling"
 591         depends on IP6_NF_IPTABLES
 592 diff -u'rNF^function' linux-2.6.16.7/net/ipv6/netfilter/Makefile linux-2.6.16.7-ROUTE/net/ipv6/netfilter/Makefile
 593 --- linux-2.6.16.7/net/ipv6/netfilter/Makefile  2006-06-14 16:05:44.000000000 +0200
 594 +++ linux-2.6.16.7-ROUTE/net/ipv6/netfilter/Makefile    2006-06-14 16:45:00.000000000 +0200
 595 @@ -22,6 +22,7 @@
 596  obj-$(CONFIG_IP6_NF_RAW) += ip6table_raw.o
 597  obj-$(CONFIG_IP6_NF_MATCH_HL) += ip6t_hl.o
 598  obj-$(CONFIG_IP6_NF_TARGET_REJECT) += ip6t_REJECT.o
 599 +obj-$(CONFIG_IP6_NF_TARGET_ROUTE) += ip6t_ROUTE.o
 600
 601  # objects for l3 independent conntrack
 602  nf_conntrack_ipv6-objs  :=  nf_conntrack_l3proto_ipv6.o nf_conntrack_proto_icmpv6.o nf_conntrack_reasm.o
 603 diff -u'rNF^function' linux-2.6.16.7/net/ipv6/netfilter/ip6t_ROUTE.c linux-2.6.16.7-ROUTE/net/ipv6/netfilter/ip6t_ROUTE.c
 604 --- linux-2.6.16.7/net/ipv6/netfilter/ip6t_ROUTE.c      1970-01-01 01:00:00.000000000 +0100
 605 +++ linux-2.6.16.7-ROUTE/net/ipv6/netfilter/ip6t_ROUTE.c        2006-06-14 16:42:44.000000000 +0200
 606 @@ -0,0 +1,308 @@
 607 +/*
 608 + * This implements the ROUTE v6 target, which enables you to setup unusual
 609 + * routes not supported by the standard kernel routing table.
 610 + *
 611 + * Copyright (C) 2003 Cedric de Launois <delaunois@info.ucl.ac.be>
 612 + *
 613 + * v 1.1 2004/11/23
 614 + *
 615 + * This software is distributed under GNU GPL v2, 1991
 616 + */
 617 +
 618 +#include <linux/module.h>
 619 +#include <linux/skbuff.h>
 620 +#include <linux/ipv6.h>
 621 +#include <linux/netfilter_ipv6/ip6_tables.h>
 622 +#include <linux/netfilter_ipv6/ip6t_ROUTE.h>
 623 +#include <linux/netdevice.h>
 624 +#include <net/ipv6.h>
 625 +#include <net/ndisc.h>
 626 +#include <net/ip6_route.h>
 627 +#include <linux/icmpv6.h>
 628 +
 629 +#if 1
 630 +#define DEBUGP printk
 631 +#else
 632 +#define DEBUGP(format, args...)
 633 +#endif
 634 +
 635 +#define NIP6(addr) \
 636 +       ntohs((addr).s6_addr16[0]), \
 637 +       ntohs((addr).s6_addr16[1]), \
 638 +       ntohs((addr).s6_addr16[2]), \
 639 +       ntohs((addr).s6_addr16[3]), \
 640 +       ntohs((addr).s6_addr16[4]), \
 641 +       ntohs((addr).s6_addr16[5]), \
 642 +       ntohs((addr).s6_addr16[6]), \
 643 +       ntohs((addr).s6_addr16[7])
 644 +
 645 +/* Route the packet according to the routing keys specified in
 646 + * route_info. Keys are :
 647 + *  - ifindex :
 648 + *      0 if no oif preferred,
 649 + *      otherwise set to the index of the desired oif
 650 + *  - route_info->gw :
 651 + *      0 if no gateway specified,
 652 + *      otherwise set to the next host to which the pkt must be routed
 653 + * If success, skb->dev is the output device to which the packet must
 654 + * be sent and skb->dst is not NULL
 655 + *
 656 + * RETURN:  1 if the packet was succesfully routed to the
 657 + *            destination desired
 658 + *          0 if the kernel routing table could not route the packet
 659 + *            according to the keys specified
 660 + */
 661 +static int
 662 +route6(struct sk_buff *skb,
 663 +       unsigned int ifindex,
 664 +       const struct ip6t_route_target_info *route_info)
 665 +{
 666 +       struct rt6_info *rt = NULL;
 667 +       struct ipv6hdr *ipv6h = skb->nh.ipv6h;
 668 +       struct in6_addr *gw = (struct in6_addr*)&route_info->gw;
 669 +
 670 +       DEBUGP("ip6t_ROUTE: called with: ");
 671 +       DEBUGP("DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(ipv6h->daddr));
 672 +       DEBUGP("GATEWAY=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(*gw));
 673 +       DEBUGP("OUT=%s\n", route_info->oif);
 674 +
 675 +       if (ipv6_addr_any(gw))
 676 +               rt = rt6_lookup(&ipv6h->daddr, &ipv6h->saddr, ifindex, 1);
 677 +       else
 678 +               rt = rt6_lookup(gw, &ipv6h->saddr, ifindex, 1);
 679 +
 680 +       if (!rt)
 681 +               goto no_route;
 682 +
 683 +       DEBUGP("ip6t_ROUTE: routing gives: ");
 684 +       DEBUGP("DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(rt->rt6i_dst.addr));
 685 +       DEBUGP("GATEWAY=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(rt->rt6i_gateway));
 686 +       DEBUGP("OUT=%s\n", rt->rt6i_dev->name);
 687 +
 688 +       if (ifindex && rt->rt6i_dev->ifindex!=ifindex)
 689 +               goto wrong_route;
 690 +
 691 +       if (!rt->rt6i_nexthop) {
 692 +               DEBUGP("ip6t_ROUTE: discovering neighbour\n");
 693 +               rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_dst.addr);
 694 +       }
 695 +
 696 +       /* Drop old route. */
 697 +       dst_release(skb->dst);
 698 +       skb->dst = &rt->u.dst;
 699 +       skb->dev = rt->rt6i_dev;
 700 +       return 1;
 701 +
 702 + wrong_route:
 703 +       dst_release(&rt->u.dst);
 704 + no_route:
 705 +       if (!net_ratelimit())
 706 +               return 0;
 707 +
 708 +       printk("ip6t_ROUTE: no explicit route found ");
 709 +       if (ifindex)
 710 +               printk("via interface %s ", route_info->oif);
 711 +       if (!ipv6_addr_any(gw))
 712 +               printk("via gateway %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x", NIP6(*gw));
 713 +       printk("\n");
 714 +       return 0;
 715 +}
 716 +
 717 +
 718 +/* Stolen from ip6_output_finish
 719 + * PRE : skb->dev is set to the device we are leaving by
 720 + *       skb->dst is not NULL
 721 + * POST: the packet is sent with the link layer header pushed
 722 + *       the packet is destroyed
 723 + */
 724 +static void ip_direct_send(struct sk_buff *skb)
 725 +{
 726 +       struct dst_entry *dst = skb->dst;
 727 +       struct hh_cache *hh = dst->hh;
 728 +
 729 +       if (hh) {
 730 +               read_lock_bh(&hh->hh_lock);
 731 +               memcpy(skb->data - 16, hh->hh_data, 16);
 732 +               read_unlock_bh(&hh->hh_lock);
 733 +               skb_push(skb, hh->hh_len);
 734 +               hh->hh_output(skb);
 735 +       } else if (dst->neighbour)
 736 +               dst->neighbour->output(skb);
 737 +       else {
 738 +               if (net_ratelimit())
 739 +                       DEBUGP(KERN_DEBUG "ip6t_ROUTE: no hdr & no neighbour cache!\n");
 740 +               kfree_skb(skb);
 741 +       }
 742 +}
 743 +
 744 +
 745 +static unsigned int
 746 +route6_oif(const struct ip6t_route_target_info *route_info,
 747 +          struct sk_buff *skb)
 748 +{
 749 +       unsigned int ifindex = 0;
 750 +       struct net_device *dev_out = NULL;
 751 +
 752 +       /* The user set the interface name to use.
 753 +        * Getting the current interface index.
 754 +        */
 755 +       if ((dev_out = dev_get_by_name(route_info->oif))) {
 756 +               ifindex = dev_out->ifindex;
 757 +       } else {
 758 +               /* Unknown interface name : packet dropped */
 759 +               if (net_ratelimit())
 760 +                       DEBUGP("ip6t_ROUTE: oif interface %s not found\n", route_info->oif);
 761 +
 762 +               if (route_info->flags & IP6T_ROUTE_CONTINUE)
 763 +                       return IP6T_CONTINUE;
 764 +               else
 765 +                       return NF_DROP;
 766 +       }
 767 +
 768 +       /* Trying the standard way of routing packets */
 769 +       if (route6(skb, ifindex, route_info)) {
 770 +               dev_put(dev_out);
 771 +               if (route_info->flags & IP6T_ROUTE_CONTINUE)
 772 +                       return IP6T_CONTINUE;
 773 +
 774 +               ip_direct_send(skb);
 775 +               return NF_STOLEN;
 776 +       } else
 777 +               return NF_DROP;
 778 +}
 779 +
 780 +
 781 +static unsigned int
 782 +route6_gw(const struct ip6t_route_target_info *route_info,
 783 +         struct sk_buff *skb)
 784 +{
 785 +       if (route6(skb, 0, route_info)) {
 786 +               if (route_info->flags & IP6T_ROUTE_CONTINUE)
 787 +                       return IP6T_CONTINUE;
 788 +
 789 +               ip_direct_send(skb);
 790 +               return NF_STOLEN;
 791 +       } else
 792 +               return NF_DROP;
 793 +}
 794 +
 795 +
 796 +static unsigned int
 797 +ip6t_route_target(struct sk_buff **pskb,
 798 +                 const struct net_device *in,
 799 +                 const struct net_device *out,
 800 +                 unsigned int hooknum,
 801 +                 const void *targinfo,
 802 +                 void *userinfo)
 803 +{
 804 +       const struct ip6t_route_target_info *route_info = targinfo;
 805 +       struct sk_buff *skb = *pskb;
 806 +       struct in6_addr *gw = (struct in6_addr*)&route_info->gw;
 807 +       unsigned int res;
 808 +
 809 +       if (route_info->flags & IP6T_ROUTE_CONTINUE)
 810 +               goto do_it;
 811 +
 812 +       /* If we are at PREROUTING or INPUT hook
 813 +        * the TTL isn't decreased by the IP stack
 814 +        */
 815 +       if (hooknum == NF_IP6_PRE_ROUTING ||
 816 +           hooknum == NF_IP6_LOCAL_IN) {
 817 +
 818 +               struct ipv6hdr *ipv6h = skb->nh.ipv6h;
 819 +
 820 +               if (ipv6h->hop_limit <= 1) {
 821 +                       /* Force OUTPUT device used as source address */
 822 +                       skb->dev = skb->dst->dev;
 823 +
 824 +                       icmpv6_send(skb, ICMPV6_TIME_EXCEED,
 825 +                                   ICMPV6_EXC_HOPLIMIT, 0, skb->dev);
 826 +
 827 +                       return NF_DROP;
 828 +               }
 829 +
 830 +               ipv6h->hop_limit--;
 831 +       }
 832 +
 833 +       if ((route_info->flags & IP6T_ROUTE_TEE)) {
 834 +               /*
 835 +                * Copy the *pskb, and route the copy. Will later return
 836 +                * IP6T_CONTINUE for the original skb, which should continue
 837 +                * on its way as if nothing happened. The copy should be
 838 +                * independantly delivered to the ROUTE --gw.
 839 +                */
 840 +               skb = skb_copy(*pskb, GFP_ATOMIC);
 841 +               if (!skb) {
 842 +                       if (net_ratelimit())
 843 +                               DEBUGP(KERN_DEBUG "ip6t_ROUTE: copy failed!\n");
 844 +                       return IP6T_CONTINUE;
 845 +               }
 846 +       }
 847 +
 848 +do_it:
 849 +       if (route_info->oif[0]) {
 850 +               res = route6_oif(route_info, skb);
 851 +       } else if (!ipv6_addr_any(gw)) {
 852 +               res = route6_gw(route_info, skb);
 853 +       } else {
 854 +               if (net_ratelimit())
 855 +                       DEBUGP(KERN_DEBUG "ip6t_ROUTE: no parameter !\n");
 856 +               res = IP6T_CONTINUE;
 857 +       }
 858 +
 859 +       if ((route_info->flags & IP6T_ROUTE_TEE))
 860 +               res = IP6T_CONTINUE;
 861 +
 862 +       return res;
 863 +}
 864 +
 865 +
 866 +static int
 867 +ip6t_route_checkentry(const char *tablename,
 868 +                     const struct ip6t_entry *e,
 869 +                     void *targinfo,
 870 +                     unsigned int targinfosize,
 871 +                     unsigned int hook_mask)
 872 +{
 873 +       if (strcmp(tablename, "mangle") != 0) {
 874 +               printk("ip6t_ROUTE: can only be called from \"mangle\" table.\n");
 875 +               return 0;
 876 +       }
 877 +
 878 +       if (targinfosize != IP6T_ALIGN(sizeof(struct ip6t_route_target_info))) {
 879 +               printk(KERN_WARNING "ip6t_ROUTE: targinfosize %u != %Zu\n",
 880 +                      targinfosize,
 881 +                      IP6T_ALIGN(sizeof(struct ip6t_route_target_info)));
 882 +               return 0;
 883 +       }
 884 +
 885 +       return 1;
 886 +}
 887 +
 888 +
 889 +static struct ip6t_target ip6t_route_reg = {
 890 +       .name       = "ROUTE",
 891 +       .target     = ip6t_route_target,
 892 +       .checkentry = ip6t_route_checkentry,
 893 +       .me         = THIS_MODULE
 894 +};
 895 +
 896 +
 897 +static int __init init(void)
 898 +{
 899 +       printk(KERN_DEBUG "registering ipv6 ROUTE target\n");
 900 +       if (ip6t_register_target(&ip6t_route_reg))
 901 +               return -EINVAL;
 902 +
 903 +       return 0;
 904 +}
 905 +
 906 +
 907 +static void __exit fini(void)
 908 +{
 909 +       ip6t_unregister_target(&ip6t_route_reg);
 910 +}
 911 +
 912 +module_init(init);
 913 +module_exit(fini);
 914 +MODULE_LICENSE("GPL");