target/linux/generic-2.6/patches-2.6.22/170-netfilter_chaostables.patch

   1 diff -urN linux-2.6.21.1.old/include/linux/netfilter/oot_conntrack.h linux-2.6.21.1.dev/include/linux/netfilter/oot_conntrack.h
   2 --- linux-2.6.21.1.old/include/linux/netfilter/oot_conntrack.h  1970-01-01 01:00:00.000000000 +0100
   3 +++ linux-2.6.21.1.dev/include/linux/netfilter/oot_conntrack.h  2007-05-26 20:40:10.922195992 +0200
   4 @@ -0,0 +1,5 @@
   5 +#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
   6 +#      include <linux/netfilter_ipv4/ip_conntrack.h>
   7 +#else /* linux-2.6.20+ */
   8 +#      include <net/netfilter/nf_nat_rule.h>
   9 +#endif
  10 diff -urN linux-2.6.21.1.old/include/linux/netfilter/oot_trans.h linux-2.6.21.1.dev/include/linux/netfilter/oot_trans.h
  11 --- linux-2.6.21.1.old/include/linux/netfilter/oot_trans.h      1970-01-01 01:00:00.000000000 +0100
  12 +++ linux-2.6.21.1.dev/include/linux/netfilter/oot_trans.h      2007-05-26 20:40:10.940193256 +0200
  13 @@ -0,0 +1,14 @@
  14 +/* Out of tree workarounds */
  15 +#include <linux/version.h>
  16 +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
  17 +#      define HAVE_MATCHINFOSIZE 1
  18 +#      define HAVE_TARGUSERINFO 1
  19 +#      define HAVE_TARGINFOSIZE 1
  20 +#endif
  21 +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
  22 +#      define nfmark mark
  23 +#endif
  24 +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 21)
  25 +#      define tcp_v4_check(tcph, tcph_sz, s, d, csp) \
  26 +               tcp_v4_check((tcph_sz), (s), (d), (csp))
  27 +#endif
  28 diff -urN linux-2.6.21.1.old/include/linux/netfilter/xt_CHAOS.h linux-2.6.21.1.dev/include/linux/netfilter/xt_CHAOS.h
  29 --- linux-2.6.21.1.old/include/linux/netfilter/xt_CHAOS.h       1970-01-01 01:00:00.000000000 +0100
  30 +++ linux-2.6.21.1.dev/include/linux/netfilter/xt_CHAOS.h       2007-05-26 20:40:10.940193256 +0200
  31 @@ -0,0 +1,14 @@
  32 +#ifndef _LINUX_XT_CHAOS_H
  33 +#define _LINUX_XT_CHAOS_H 1
  34 +
  35 +enum xt_chaos_variant {
  36 +       XTCHAOS_NORMAL,
  37 +       XTCHAOS_TARPIT,
  38 +       XTCHAOS_DELUDE,
  39 +};
  40 +
  41 +struct xt_chaos_info {
  42 +       enum xt_chaos_variant variant;
  43 +};
  44 +
  45 +#endif /* _LINUX_XT_CHAOS_H */
  46 diff -urN linux-2.6.21.1.old/include/linux/netfilter/xt_portscan.h linux-2.6.21.1.dev/include/linux/netfilter/xt_portscan.h
  47 --- linux-2.6.21.1.old/include/linux/netfilter/xt_portscan.h    1970-01-01 01:00:00.000000000 +0100
  48 +++ linux-2.6.21.1.dev/include/linux/netfilter/xt_portscan.h    2007-05-26 20:40:10.940193256 +0200
  49 @@ -0,0 +1,8 @@
  50 +#ifndef _LINUX_XT_PORTSCAN_H
  51 +#define _LINUX_XT_PORTSCAN_H 1
  52 +
  53 +struct xt_portscan_info {
  54 +       unsigned int match_stealth, match_syn, match_cn, match_gr;
  55 +};
  56 +
  57 +#endif /* _LINUX_XT_PORTSCAN_H */
  58 diff -urN linux-2.6.21.1.old/net/netfilter/find_match.c linux-2.6.21.1.dev/net/netfilter/find_match.c
  59 --- linux-2.6.21.1.old/net/netfilter/find_match.c       1970-01-01 01:00:00.000000000 +0100
  60 +++ linux-2.6.21.1.dev/net/netfilter/find_match.c       2007-05-26 20:40:10.970188696 +0200
  61 @@ -0,0 +1,39 @@
  62 +/*
  63 +    xt_request_find_match
  64 +    by Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
  65 +
  66 +    Based upon linux-2.6.18.5/net/netfilter/x_tables.c:
  67 +    Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
  68 +    This program is free software; you can redistribute it and/or modify
  69 +    it under the terms of the GNU General Public License version 2 as
  70 +    published by the Free Software Foundation.
  71 +*/
  72 +#include <linux/err.h>
  73 +#include <linux/netfilter_arp.h>
  74 +#include <linux/socket.h>
  75 +#include <linux/netfilter/x_tables.h>
  76 +
  77 +/*
  78 + * Yeah this code is sub-optimal, but the function is missing in
  79 + * mainline so far. -jengelh
  80 + */
  81 +static struct xt_match *xt_request_find_match_lo(int af, const char *name,
  82 +    u8 revision)
  83 +{
  84 +       static const char *const xt_prefix[] = {
  85 +               [AF_INET]  = "ip",
  86 +               [AF_INET6] = "ip6",
  87 +               [NF_ARP]   = "arp",
  88 +       };
  89 +       struct xt_match *match;
  90 +
  91 +       match = try_then_request_module(xt_find_match(af, name, revision),
  92 +               "%st_%s", xt_prefix[af], name);
  93 +       if(IS_ERR(match) || match == NULL)
  94 +               return NULL;
  95 +
  96 +       return match;
  97 +}
  98 +
  99 +/* In case it goes into mainline, let this out-of-tree package compile */
 100 +#define xt_request_find_match xt_request_find_match_lo
 101 diff -urN linux-2.6.21.1.old/net/netfilter/Kconfig linux-2.6.21.1.dev/net/netfilter/Kconfig
 102 --- linux-2.6.21.1.old/net/netfilter/Kconfig    2007-04-27 23:49:26.000000000 +0200
 103 +++ linux-2.6.21.1.dev/net/netfilter/Kconfig    2007-05-26 20:40:11.003183680 +0200
 104 @@ -255,6 +255,14 @@
 105
 106  # alphabetically ordered list of targets
 107
 108 +config NETFILTER_XT_TARGET_CHAOS
 109 +       tristate '"CHAOS" target support'
 110 +       depends on NETFILTER_XTABLES
 111 +       help
 112 +         This option adds a `CHAOS' target.
 113 +
 114 +         To compile it as a module, choose M here.  If unsure, say N.
 115 +
 116  config NETFILTER_XT_TARGET_CLASSIFY
 117         tristate '"CLASSIFY" target support'
 118         depends on NETFILTER_XTABLES
 119 @@ -282,6 +290,14 @@
 120           <file:Documentation/kbuild/modules.txt>.  The module will be called
 121           ipt_CONNMARK.ko.  If unsure, say `N'.
 122
 123 +config NETFILTER_XT_TARGET_DELUDE
 124 +       tristate '"DELUDE" target support'
 125 +       depends on NETFILTER_XTABLES
 126 +       help
 127 +         This option adds a `DELUDE' target.
 128 +
 129 +         To compile it as a module, choose M here.  If unsure, say N.
 130 +
 131  config NETFILTER_XT_TARGET_DSCP
 132         tristate '"DSCP" target support'
 133         depends on NETFILTER_XTABLES
 134 @@ -526,6 +542,14 @@
 135
 136           To compile it as a module, choose M here.  If unsure, say N.
 137
 138 +config NETFILTER_XT_MATCH_PORTSCAN
 139 +       tristate '"portscan" match support'
 140 +       depends on NETFILTER_XTABLES
 141 +       help
 142 +         This option adds a 'portscan' match support.
 143 +
 144 +         To compile it as a module, choose M here.  If unsure, say N.
 145 +
 146  config NETFILTER_XT_MATCH_MULTIPORT
 147         tristate "Multiple port match support"
 148         depends on NETFILTER_XTABLES
 149 diff -urN linux-2.6.21.1.old/net/netfilter/Makefile linux-2.6.21.1.dev/net/netfilter/Makefile
 150 --- linux-2.6.21.1.old/net/netfilter/Makefile   2007-04-27 23:49:26.000000000 +0200
 151 +++ linux-2.6.21.1.dev/net/netfilter/Makefile   2007-05-26 20:40:11.003183680 +0200
 152 @@ -37,8 +37,10 @@
 153  obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o
 154
 155  # targets
 156 +obj-$(CONFIG_NETFILTER_XT_TARGET_CHAOS) += xt_CHAOS.o
 157  obj-$(CONFIG_NETFILTER_XT_TARGET_CLASSIFY) += xt_CLASSIFY.o
 158  obj-$(CONFIG_NETFILTER_XT_TARGET_CONNMARK) += xt_CONNMARK.o
 159 +obj-$(CONFIG_NETFILTER_XT_TARGET_DELUDE) += xt_DELUDE.o
 160  obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
 161  obj-$(CONFIG_NETFILTER_XT_TARGET_MARK) += xt_MARK.o
 162  obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
 163 @@ -63,6 +65,7 @@
 164  obj-$(CONFIG_NETFILTER_XT_MATCH_MARK) += xt_mark.o
 165  obj-$(CONFIG_NETFILTER_XT_MATCH_MULTIPORT) += xt_multiport.o
 166  obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o
 167 +obj-$(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) += xt_portscan.o
 168  obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o
 169  obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA) += xt_quota.o
 170  obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
 171 diff -urN linux-2.6.21.1.old/net/netfilter/xt_CHAOS.c linux-2.6.21.1.dev/net/netfilter/xt_CHAOS.c
 172 --- linux-2.6.21.1.old/net/netfilter/xt_CHAOS.c 1970-01-01 01:00:00.000000000 +0100
 173 +++ linux-2.6.21.1.dev/net/netfilter/xt_CHAOS.c 2007-05-26 20:40:11.004183528 +0200
 174 @@ -0,0 +1,204 @@
 175 +/*
 176 +       CHAOS target for netfilter
 177 +
 178 +       Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
 179 +       This program is free software; you can redistribute it and/or modify
 180 +       it under the terms of the GNU General Public License version 2 as
 181 +       published by the Free Software Foundation.
 182 +*/
 183 +#include <linux/icmp.h>
 184 +#include <linux/in.h>
 185 +#include <linux/ip.h>
 186 +#include <linux/module.h>
 187 +#include <linux/skbuff.h>
 188 +#include <linux/stat.h>
 189 +#include <linux/netfilter/x_tables.h>
 190 +#include <linux/netfilter/xt_tcpudp.h>
 191 +#include <linux/netfilter_ipv4/ipt_REJECT.h>
 192 +#include <net/ip.h>
 193 +#include <linux/netfilter/xt_CHAOS.h>
 194 +#include "find_match.c"
 195 +#include <linux/netfilter/oot_trans.h>
 196 +#define PFX KBUILD_MODNAME ": "
 197 +
 198 +/* Module parameters */
 199 +static unsigned int reject_percentage = ~0U * .01;
 200 +static unsigned int delude_percentage = ~0U * .0101;
 201 +module_param(reject_percentage, uint, S_IRUGO | S_IWUSR);
 202 +module_param(delude_percentage, uint, S_IRUGO | S_IWUSR);
 203 +
 204 +/* References to other matches/targets */
 205 +static struct xt_match *xm_tcp;
 206 +static struct xt_target *xt_delude, *xt_reject, *xt_tarpit;
 207 +
 208 +static int have_delude, have_tarpit;
 209 +
 210 +/* Static data for other matches/targets */
 211 +static const struct ipt_reject_info reject_params = {
 212 +       .with = ICMP_HOST_UNREACH,
 213 +};
 214 +
 215 +static const struct xt_tcp tcp_params = {
 216 +       .spts = {0, ~0},
 217 +       .dpts = {0, ~0},
 218 +};
 219 +
 220 +/* CHAOS functions */
 221 +static void xt_chaos_total(const struct xt_chaos_info *info,
 222 +    struct sk_buff **pskb, const struct net_device *in,
 223 +    const struct net_device *out, unsigned int hooknum)
 224 +{
 225 +       const int protoff = ip_hdrlen(*pskb);
 226 +       const int offset  = ntohs(ip_hdr(*pskb)->frag_off) & IP_OFFSET;
 227 +       const struct xt_target *destiny;
 228 +       int hotdrop = 0, ret;
 229 +
 230 +       ret = xm_tcp->match(*pskb, in, out, xm_tcp, &tcp_params,
 231 +                           offset, protoff, &hotdrop);
 232 +       if(!ret || hotdrop || (unsigned int)net_random() > delude_percentage)
 233 +               return;
 234 +
 235 +       destiny = (info->variant == XTCHAOS_TARPIT) ? xt_tarpit : xt_delude;
 236 +#ifdef HAVE_TARGUSERINFO
 237 +       destiny->target(pskb, in, out, hooknum, destiny, NULL, NULL);
 238 +#else
 239 +       destiny->target(pskb, in, out, hooknum, destiny, NULL);
 240 +#endif
 241 +       return;
 242 +}
 243 +
 244 +static unsigned int xt_chaos_target(struct sk_buff **pskb,
 245 +    const struct net_device *in, const struct net_device *out,
 246 +    unsigned int hooknum, const struct xt_target *target, const void *targinfo
 247 +#ifdef HAVE_TARGUSERINFO
 248 +    ,
 249 +    void *userinfo
 250 +#endif
 251 +    )
 252 +{
 253 +       /* Equivalent to:
 254 +        * -A chaos -m statistic --mode random --probability \
 255 +        *         $reject_percentage -j REJECT --reject-with host-unreach;
 256 +        * -A chaos -p tcp -m statistic --mode random --probability \
 257 +        *         $delude_percentage -j DELUDE;
 258 +        * -A chaos -j DROP;
 259 +        */
 260 +       const struct xt_chaos_info *info = targinfo;
 261 +
 262 +       if((unsigned int)net_random() <= reject_percentage)
 263 +#ifdef HAVE_TARGUSERINFO
 264 +               return xt_reject->target(pskb, in, out, hooknum, target,
 265 +                      &reject_params, userinfo);
 266 +#else
 267 +               return xt_reject->target(pskb, in, out, hooknum, target,
 268 +                      &reject_params);
 269 +#endif
 270 +
 271 +       /* TARPIT/DELUDE may not be called from the OUTPUT chain */
 272 +       if(ip_hdr(*pskb)->protocol == IPPROTO_TCP &&
 273 +         info->variant != XTCHAOS_NORMAL && hooknum != NF_IP_LOCAL_OUT)
 274 +               xt_chaos_total(info, pskb, in, out, hooknum);
 275 +
 276 +       return NF_DROP;
 277 +}
 278 +
 279 +static int xt_chaos_checkentry(const char *tablename, const void *entry,
 280 +    const struct xt_target *target, void *targinfo,
 281 +#ifdef HAVE_TARGINFOSIZE
 282 +    unsigned int targinfosize,
 283 +#endif
 284 +    unsigned int hook_mask)
 285 +{
 286 +       const struct xt_chaos_info *info = targinfo;
 287 +       if(info->variant == XTCHAOS_DELUDE && !have_delude) {
 288 +               printk(KERN_WARNING PFX "Error: Cannot use --delude when "
 289 +                      "DELUDE module not available\n");
 290 +               return 0;
 291 +       }
 292 +       if(info->variant == XTCHAOS_TARPIT && !have_tarpit) {
 293 +               printk(KERN_WARNING PFX "Error: Cannot use --tarpit when "
 294 +                      "TARPIT module not available\n");
 295 +               return 0;
 296 +       }
 297 +       return 1;
 298 +}
 299 +
 300 +static struct xt_target xt_chaos_info = {
 301 +       .name       = "CHAOS",
 302 +       .target     = xt_chaos_target,
 303 +       .checkentry = xt_chaos_checkentry,
 304 +       .table      = "filter",
 305 +       .targetsize = sizeof(struct xt_chaos_info),
 306 +       .hooks      = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) |
 307 +                     (1 << NF_IP_LOCAL_OUT),
 308 +       .family     = AF_INET,
 309 +       .me         = THIS_MODULE,
 310 +};
 311 +
 312 +static int __init xt_chaos_init(void)
 313 +{
 314 +       int ret = -EINVAL;
 315 +
 316 +       xm_tcp = xt_request_find_match(AF_INET, "tcp", 0);
 317 +       if(xm_tcp == NULL) {
 318 +               printk(KERN_WARNING PFX "Error: Could not find or load "
 319 +                      "\"tcp\" match\n");
 320 +               return -EINVAL;
 321 +       }
 322 +
 323 +       xt_reject = xt_request_find_target(AF_INET, "REJECT", 0);
 324 +       if(xt_reject == NULL) {
 325 +               printk(KERN_WARNING PFX "Error: Could not find or load "
 326 +                      "\"REJECT\" target\n");
 327 +               goto out2;
 328 +       }
 329 +
 330 +       xt_tarpit   = xt_request_find_target(AF_INET, "TARPIT", 0);
 331 +       have_tarpit = xt_tarpit != NULL;
 332 +       if(!have_tarpit)
 333 +               printk(KERN_WARNING PFX "Warning: Could not find or load "
 334 +                      "\"TARPIT\" target\n");
 335 +
 336 +       xt_delude   = xt_request_find_target(AF_INET, "DELUDE", 0);
 337 +       have_delude = xt_delude != NULL;
 338 +       if(!have_delude)
 339 +               printk(KERN_WARNING PFX "Warning: Could not find or load "
 340 +                      "\"DELUDE\" target\n");
 341 +
 342 +       if((ret = xt_register_target(&xt_chaos_info)) != 0) {
 343 +               printk(KERN_WARNING PFX "xt_register_target returned "
 344 +                      "error %d\n", ret);
 345 +               goto out3;
 346 +       }
 347 +
 348 +       return 0;
 349 +
 350 + out3:
 351 +       if(have_delude)
 352 +               module_put(xt_delude->me);
 353 +       if(have_tarpit)
 354 +               module_put(xt_tarpit->me);
 355 +       module_put(xt_reject->me);
 356 + out2:
 357 +       module_put(xm_tcp->me);
 358 +       return ret;
 359 +}
 360 +
 361 +static void __exit xt_chaos_exit(void)
 362 +{
 363 +       xt_unregister_target(&xt_chaos_info);
 364 +       module_put(xm_tcp->me);
 365 +       module_put(xt_reject->me);
 366 +       if(have_delude)
 367 +               module_put(xt_delude->me);
 368 +       if(have_tarpit)
 369 +               module_put(xt_tarpit->me);
 370 +       return;
 371 +}
 372 +
 373 +module_init(xt_chaos_init);
 374 +module_exit(xt_chaos_exit);
 375 +MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
 376 +MODULE_DESCRIPTION("netfilter CHAOS target");
 377 +MODULE_LICENSE("GPL");
 378 +MODULE_ALIAS("ipt_CHAOS");
 379 diff -urN linux-2.6.21.1.old/net/netfilter/xt_DELUDE.c linux-2.6.21.1.dev/net/netfilter/xt_DELUDE.c
 380 --- linux-2.6.21.1.old/net/netfilter/xt_DELUDE.c        1970-01-01 01:00:00.000000000 +0100
 381 +++ linux-2.6.21.1.dev/net/netfilter/xt_DELUDE.c        2007-05-26 20:40:11.004183528 +0200
 382 @@ -0,0 +1,288 @@
 383 +/*
 384 +       DELUDE target
 385 +       Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2007
 386 +
 387 +       Based upon linux-2.6.18.5/net/ipv4/netfilter/ipt_REJECT.c:
 388 +       (C) 1999-2001 Paul `Rusty' Russell
 389 +       (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
 390 +
 391 +       xt_DELUDE acts like REJECT, but does reply with SYN-ACK on SYN.
 392 +
 393 +       This program is free software; you can redistribute it and/or modify
 394 +       it under the terms of the GNU General Public License version 2 as
 395 +       published by the Free Software Foundation.
 396 +*/
 397 +#include <linux/module.h>
 398 +#include <linux/skbuff.h>
 399 +#include <linux/ip.h>
 400 +#include <linux/random.h>
 401 +#include <linux/tcp.h>
 402 +#include <linux/udp.h>
 403 +#include <linux/icmp.h>
 404 +#include <net/icmp.h>
 405 +#include <net/ip.h>
 406 +#include <net/tcp.h>
 407 +#include <net/route.h>
 408 +#include <net/dst.h>
 409 +#include <linux/netfilter_ipv4/ip_tables.h>
 410 +#ifdef CONFIG_BRIDGE_NETFILTER
 411 +#      include <linux/netfilter_bridge.h>
 412 +#endif
 413 +#include <linux/netfilter/oot_trans.h>
 414 +#define PFX KBUILD_MODNAME ": "
 415 +
 416 +static inline struct rtable *route_reverse(struct sk_buff *skb,
 417 +                                          struct tcphdr *tcph, int hook)
 418 +{
 419 +       struct iphdr *iph = ip_hdr(skb);
 420 +       struct dst_entry *odst;
 421 +       struct flowi fl = {};
 422 +       struct rtable *rt;
 423 +
 424 +       /* We don't require ip forwarding to be enabled to be able to
 425 +        * send a RST reply for bridged traffic. */
 426 +       if (hook != NF_IP_FORWARD
 427 +#ifdef CONFIG_BRIDGE_NETFILTER
 428 +           || (skb->nf_bridge && skb->nf_bridge->mask & BRNF_BRIDGED)
 429 +#endif
 430 +          ) {
 431 +               fl.nl_u.ip4_u.daddr = iph->saddr;
 432 +               if (hook == NF_IP_LOCAL_IN)
 433 +                       fl.nl_u.ip4_u.saddr = iph->daddr;
 434 +               fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
 435 +
 436 +               if (ip_route_output_key(&rt, &fl) != 0)
 437 +                       return NULL;
 438 +       } else {
 439 +               /* non-local src, find valid iif to satisfy
 440 +                * rp-filter when calling ip_route_input. */
 441 +               fl.nl_u.ip4_u.daddr = iph->daddr;
 442 +               if (ip_route_output_key(&rt, &fl) != 0)
 443 +                       return NULL;
 444 +
 445 +               odst = skb->dst;
 446 +               if (ip_route_input(skb, iph->saddr, iph->daddr,
 447 +                                  RT_TOS(iph->tos), rt->u.dst.dev) != 0) {
 448 +                       dst_release(&rt->u.dst);
 449 +                       return NULL;
 450 +               }
 451 +               dst_release(&rt->u.dst);
 452 +               rt = (struct rtable *)skb->dst;
 453 +               skb->dst = odst;
 454 +
 455 +               fl.nl_u.ip4_u.daddr = iph->saddr;
 456 +               fl.nl_u.ip4_u.saddr = iph->daddr;
 457 +               fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
 458 +       }
 459 +
 460 +       if (rt->u.dst.error) {
 461 +               dst_release(&rt->u.dst);
 462 +               return NULL;
 463 +       }
 464 +
 465 +       fl.proto = IPPROTO_TCP;
 466 +       fl.fl_ip_sport = tcph->dest;
 467 +       fl.fl_ip_dport = tcph->source;
 468 +
 469 +       xfrm_lookup((struct dst_entry **)&rt, &fl, NULL, 0);
 470 +
 471 +       return rt;
 472 +}
 473 +
 474 +static void send_reset(struct sk_buff *oldskb, int hook)
 475 +{
 476 +       struct sk_buff *nskb;
 477 +       struct iphdr *iph = ip_hdr(oldskb);
 478 +       struct tcphdr _otcph, *oth, *tcph;
 479 +       __be16 tmp_port;
 480 +       __be32 tmp_addr;
 481 +       int needs_ack;
 482 +       unsigned int addr_type;
 483 +
 484 +       /* IP header checks: fragment. */
 485 +       if (iph->frag_off & htons(IP_OFFSET))
 486 +               return;
 487 +
 488 +       oth = skb_header_pointer(oldskb, ip_hdrlen(oldskb),
 489 +                                sizeof(_otcph), &_otcph);
 490 +       if (oth == NULL)
 491 +               return;
 492 +
 493 +       /* No RST for RST. */
 494 +       if (oth->rst)
 495 +               return;
 496 +
 497 +       /* Check checksum */
 498 +       if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), IPPROTO_TCP))
 499 +               return;
 500 +
 501 +       /* We need a linear, writeable skb.  We also need to expand
 502 +          headroom in case hh_len of incoming interface < hh_len of
 503 +          outgoing interface */
 504 +       nskb = skb_copy_expand(oldskb, LL_MAX_HEADER, skb_tailroom(oldskb),
 505 +                              GFP_ATOMIC);
 506 +       if (!nskb)
 507 +               return;
 508 +
 509 +       /* This packet will not be the same as the other: clear nf fields */
 510 +       nf_reset(nskb);
 511 +       nskb->nfmark = 0;
 512 +       skb_init_secmark(nskb);
 513 +
 514 +       skb_shinfo(nskb)->gso_size = 0;
 515 +       skb_shinfo(nskb)->gso_segs = 0;
 516 +       skb_shinfo(nskb)->gso_type = 0;
 517 +
 518 +       tcph = tcp_hdr(nskb);
 519 +
 520 +       /* Swap source and dest */
 521 +       tmp_addr = ip_hdr(nskb)->saddr;
 522 +       ip_hdr(nskb)->saddr = ip_hdr(nskb)->daddr;
 523 +       ip_hdr(nskb)->daddr = tmp_addr;
 524 +       tmp_port = tcph->source;
 525 +       tcph->source = tcph->dest;
 526 +       tcph->dest = tmp_port;
 527 +
 528 +       /* Truncate to length (no data) */
 529 +       tcph->doff = sizeof(struct tcphdr)/4;
 530 +       skb_trim(nskb, ip_hdrlen(nskb) + sizeof(struct tcphdr));
 531 +       ip_hdr(nskb)->tot_len = htons(nskb->len);
 532 +
 533 +       if(oth->syn && !oth->ack && !oth->rst && !oth->fin) {
 534 +               /* DELUDE essential part */
 535 +               tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin +
 536 +                               oldskb->len - ip_hdrlen(oldskb) -
 537 +                               (oth->doff << 2));
 538 +               tcph->seq     = htonl(secure_tcp_sequence_number(
 539 +                               ip_hdr(nskb)->saddr, ip_hdr(nskb)->daddr,
 540 +                               tcph->source, tcph->dest));
 541 +               tcph->ack     = 1;
 542 +       } else {
 543 +               if(!tcph->ack) {
 544 +                       needs_ack = 1;
 545 +                       tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin
 546 +                                             + oldskb->len - ip_hdrlen(oldskb)
 547 +                                             - (oth->doff<<2));
 548 +                       tcph->seq = 0;
 549 +               } else {
 550 +                       needs_ack = 0;
 551 +                       tcph->seq = oth->ack_seq;
 552 +                       tcph->ack_seq = 0;
 553 +               }
 554 +
 555 +               /* Reset flags */
 556 +               ((u_int8_t *)tcph)[13] = 0;
 557 +               tcph->rst = 1;
 558 +               tcph->ack = needs_ack;
 559 +       }
 560 +
 561 +
 562 +       tcph->window = 0;
 563 +       tcph->urg_ptr = 0;
 564 +
 565 +       /* Adjust TCP checksum */
 566 +       tcph->check = 0;
 567 +       tcph->check = tcp_v4_check(tcph, sizeof(struct tcphdr),
 568 +                                  ip_hdr(nskb)->saddr,
 569 +                                  ip_hdr(nskb)->daddr,
 570 +                                  csum_partial((char *)tcph,
 571 +                                               sizeof(struct tcphdr), 0));
 572 +
 573 +       /* Set DF, id = 0 */
 574 +       ip_hdr(nskb)->frag_off = htons(IP_DF);
 575 +       ip_hdr(nskb)->id = 0;
 576 +
 577 +       addr_type = RTN_UNSPEC;
 578 +       if (hook != NF_IP_FORWARD
 579 +#ifdef CONFIG_BRIDGE_NETFILTER
 580 +           || (nskb->nf_bridge && nskb->nf_bridge->mask & BRNF_BRIDGED)
 581 +#endif
 582 +          )
 583 +               addr_type = RTN_LOCAL;
 584 +
 585 +       if (ip_route_me_harder(&nskb, addr_type))
 586 +               goto free_nskb;
 587 +
 588 +       nskb->ip_summed = CHECKSUM_NONE;
 589 +
 590 +       /* Adjust IP TTL */
 591 +       ip_hdr(nskb)->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
 592 +
 593 +       /* Adjust IP checksum */
 594 +       ip_hdr(nskb)->check = 0;
 595 +       ip_hdr(nskb)->check = ip_fast_csum((unsigned char *)ip_hdr(nskb),
 596 +                                          ip_hdr(nskb)->ihl);
 597 +
 598 +       /* "Never happens" */
 599 +       if (nskb->len > dst_mtu(nskb->dst))
 600 +               goto free_nskb;
 601 +
 602 +       nf_ct_attach(nskb, oldskb);
 603 +
 604 +       NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
 605 +               dst_output);
 606 +       return;
 607 +
 608 + free_nskb:
 609 +       kfree_skb(nskb);
 610 +}
 611 +
 612 +static unsigned int xt_delude_target(struct sk_buff **pskb,
 613 +    const struct net_device *in, const struct net_device *out,
 614 +    unsigned int hooknum, const struct xt_target *target, const void *targinfo
 615 +#ifdef HAVE_TARGUSERINFO
 616 +    ,
 617 +    void *userinfo
 618 +#endif
 619 +    )
 620 +{
 621 +       /* WARNING: This code causes reentry within iptables.
 622 +          This means that the iptables jump stack is now crap.  We
 623 +          must return an absolute verdict. --RR */
 624 +       send_reset(*pskb, hooknum);
 625 +       return NF_DROP;
 626 +}
 627 +
 628 +static int xt_delude_check(const char *tablename, const void *e_void,
 629 +    const struct xt_target *target, void *targinfo,
 630 +#ifdef HAVE_TARGINFOSIZE
 631 +    unsigned int targinfosize,
 632 +#endif
 633 +    unsigned int hook_mask)
 634 +{
 635 +       if(hook_mask & ~((1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD))) {
 636 +               printk(KERN_WARNING PFX "DELUDE may not be used in chains "
 637 +                      "other than INPUT and FORWARD\n");
 638 +               return 0;
 639 +       }
 640 +       return 1;
 641 +}
 642 +
 643 +static struct xt_target xt_delude_info = {
 644 +       .name       = "DELUDE",
 645 +       .target     = xt_delude_target,
 646 +       .checkentry = xt_delude_check,
 647 +       .table      = "filter",
 648 +       .hooks      = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) |
 649 +                     (1 << NF_IP_LOCAL_OUT),
 650 +       .proto      = IPPROTO_TCP,
 651 +       .family     = AF_INET,
 652 +       .me         = THIS_MODULE,
 653 +};
 654 +
 655 +static int __init xt_delude_init(void)
 656 +{
 657 +       return xt_register_target(&xt_delude_info);
 658 +}
 659 +
 660 +static void __exit xt_delude_exit(void)
 661 +{
 662 +       xt_unregister_target(&xt_delude_info);
 663 +}
 664 +
 665 +module_init(xt_delude_init);
 666 +module_exit(xt_delude_exit);
 667 +MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
 668 +MODULE_DESCRIPTION("netfilter DELUDE target");
 669 +MODULE_LICENSE("GPL");
 670 +MODULE_ALIAS("ipt_DELUDE");
 671 diff -urN linux-2.6.21.1.old/net/netfilter/xt_portscan.c linux-2.6.21.1.dev/net/netfilter/xt_portscan.c
 672 --- linux-2.6.21.1.old/net/netfilter/xt_portscan.c      1970-01-01 01:00:00.000000000 +0100
 673 +++ linux-2.6.21.1.dev/net/netfilter/xt_portscan.c      2007-05-26 20:40:11.004183528 +0200
 674 @@ -0,0 +1,272 @@
 675 +/*
 676 +       portscan match for netfilter
 677 +
 678 +       Written by Jan Engelhardt, 2006 - 2007
 679 +       This program is free software; you can redistribute it and/or modify
 680 +       it under the terms of the GNU General Public License version 2 as
 681 +       published by the Free Software Foundation.
 682 +*/
 683 +#include <linux/in.h>
 684 +#include <linux/ip.h>
 685 +#include <linux/module.h>
 686 +#include <linux/moduleparam.h>
 687 +#include <linux/skbuff.h>
 688 +#include <linux/stat.h>
 689 +#include <linux/tcp.h>
 690 +#include <linux/types.h>
 691 +#include <linux/version.h>
 692 +#include <linux/netfilter/x_tables.h>
 693 +#include <linux/netfilter/xt_tcpudp.h>
 694 +#include <linux/netfilter/oot_conntrack.h>
 695 +#include <linux/netfilter/xt_portscan.h>
 696 +#include <linux/netfilter/oot_trans.h>
 697 +#define PFX KBUILD_MODNAME ": "
 698 +
 699 +enum {
 700 +       TCP_FLAGS_ALL3 = TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_SYN,
 701 +       TCP_FLAGS_ALL4 = TCP_FLAGS_ALL3 | TCP_FLAG_ACK,
 702 +       TCP_FLAGS_ALL6 = TCP_FLAGS_ALL4 | TCP_FLAG_PSH | TCP_FLAG_URG,
 703 +};
 704 +
 705 +/* Module parameters */
 706 +static unsigned int
 707 +       connmark_mask = ~0,
 708 +       packet_mask   = ~0,
 709 +       mark_seen     = 0x9,
 710 +       mark_synrcv   = 0x1,
 711 +       mark_closed   = 0x2,
 712 +       mark_synscan  = 0x3,
 713 +       mark_estab1   = 0x4,
 714 +       mark_estab2   = 0x5,
 715 +       mark_cnscan   = 0x6,
 716 +       mark_grscan   = 0x7,
 717 +       mark_valid    = 0x8;
 718 +
 719 +module_param(connmark_mask, uint, S_IRUGO | S_IWUSR);
 720 +module_param(packet_mask,   uint, S_IRUGO | S_IWUSR);
 721 +module_param(mark_seen,     uint, S_IRUGO | S_IWUSR);
 722 +module_param(mark_synrcv,   uint, S_IRUGO | S_IWUSR);
 723 +module_param(mark_closed,   uint, S_IRUGO | S_IWUSR);
 724 +module_param(mark_synscan,  uint, S_IRUGO | S_IWUSR);
 725 +module_param(mark_estab1,   uint, S_IRUGO | S_IWUSR);
 726 +module_param(mark_estab2,   uint, S_IRUGO | S_IWUSR);
 727 +module_param(mark_cnscan,   uint, S_IRUGO | S_IWUSR);
 728 +module_param(mark_grscan,   uint, S_IRUGO | S_IWUSR);
 729 +module_param(mark_valid,    uint, S_IRUGO | S_IWUSR);
 730 +MODULE_PARM_DESC(connmark_mask, "only set specified bits in connection mark");
 731 +MODULE_PARM_DESC(packet_mask,   "only set specified bits in packet mark");
 732 +MODULE_PARM_DESC(mark_seen,     "nfmark value for packet-seen state");
 733 +MODULE_PARM_DESC(mark_synrcv,   "connmark value for SYN Received state");
 734 +MODULE_PARM_DESC(mark_closed,   "connmark value for closed state");
 735 +MODULE_PARM_DESC(mark_synscan,  "connmark value for SYN Scan state");
 736 +MODULE_PARM_DESC(mark_estab1,   "connmark value for Established-1 state");
 737 +MODULE_PARM_DESC(mark_estab2,   "connmark value for Established-2 state");
 738 +MODULE_PARM_DESC(mark_cnscan,   "connmark value for Connect Scan state");
 739 +MODULE_PARM_DESC(mark_grscan,   "connmark value for Grab Scan state");
 740 +MODULE_PARM_DESC(mark_valid,    "connmark value for Valid state");
 741 +
 742 +/* TCP flag functions */
 743 +static inline int tflg_ack4(const struct tcphdr *th)
 744 +{
 745 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_ACK;
 746 +}
 747 +
 748 +static inline int tflg_ack6(const struct tcphdr *th)
 749 +{
 750 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL6) == TCP_FLAG_ACK;
 751 +}
 752 +
 753 +static inline int tflg_fin(const struct tcphdr *th)
 754 +{
 755 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_FIN;
 756 +}
 757 +
 758 +static inline int tflg_rst(const struct tcphdr *th)
 759 +{
 760 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_RST;
 761 +}
 762 +
 763 +static inline int tflg_rstack(const struct tcphdr *th)
 764 +{
 765 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
 766 +              (TCP_FLAG_ACK | TCP_FLAG_RST);
 767 +}
 768 +
 769 +static inline int tflg_syn(const struct tcphdr *th)
 770 +{
 771 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_SYN;
 772 +}
 773 +
 774 +static inline int tflg_synack(const struct tcphdr *th)
 775 +{
 776 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
 777 +              (TCP_FLAG_SYN | TCP_FLAG_ACK);
 778 +}
 779 +
 780 +/* portscan functions */
 781 +static inline int xt_portscan_stealth(const struct tcphdr *th)
 782 +{
 783 +       /*
 784 +        * "Connection refused" replies to our own probes must not be matched.
 785 +        */
 786 +       if(tflg_rstack(th))
 787 +               return 0;
 788 +
 789 +       if(tflg_rst(th) && printk_ratelimit()) {
 790 +               printk(KERN_WARNING PFX "Warning: Pure RST received\n");
 791 +               return 0;
 792 +       }
 793 +
 794 +       /*
 795 +        * -p tcp ! --syn -m conntrack --ctstate INVALID: Looking for non-start
 796 +        * packets that are not associated with any connection -- this will
 797 +        * match most scan types (NULL, XMAS, FIN) and ridiculous flag
 798 +        * combinations (SYN-RST, SYN-FIN, SYN-FIN-RST, FIN-RST, etc.).
 799 +        */
 800 +       return !tflg_syn(th);
 801 +}
 802 +
 803 +static inline int xt_portscan_full(int mark, enum ip_conntrack_info ctstate,
 804 +    int loopback, const struct tcphdr *tcph, int payload_len)
 805 +{
 806 +       if(mark == mark_estab2) {
 807 +               /*
 808 +                * -m connmark --mark $ESTAB2
 809 +                */
 810 +               if(tflg_ack4(tcph) && payload_len == 0)
 811 +                       return mark; /* keep mark */
 812 +               else if(tflg_rst(tcph) || tflg_fin(tcph))
 813 +                       return mark_grscan;
 814 +               else
 815 +                       return mark_valid;
 816 +       } else if(mark == mark_estab1) {
 817 +               /*
 818 +                * -m connmark --mark $ESTAB1
 819 +                */
 820 +               if(tflg_rst(tcph) || tflg_fin(tcph))
 821 +                       return mark_cnscan;
 822 +               else if(!loopback && tflg_ack4(tcph) && payload_len == 0)
 823 +                       return mark_estab2;
 824 +               else
 825 +                       return mark_valid;
 826 +       } else if(mark == mark_synrcv) {
 827 +               /*
 828 +                * -m connmark --mark $SYN
 829 +                */
 830 +               if(loopback && tflg_synack(tcph))
 831 +                       return mark; /* keep mark */
 832 +               else if(loopback && tflg_rstack(tcph))
 833 +                       return mark_closed;
 834 +               else if(tflg_ack6(tcph))
 835 +                       return mark_estab1;
 836 +               else
 837 +                       return mark_synscan;
 838 +       } else if(ctstate == IP_CT_NEW && tflg_syn(tcph)) {
 839 +               /*
 840 +                * -p tcp --syn --ctstate NEW
 841 +                */
 842 +               return mark_synrcv;
 843 +       }
 844 +       return mark;
 845 +}
 846 +
 847 +static int xt_portscan_match(const struct sk_buff *skb,
 848 +    const struct net_device *in, const struct net_device *out,
 849 +    const struct xt_match *match, const void *matchinfo, int offset,
 850 +    unsigned int protoff, int *hotdrop)
 851 +{
 852 +       const struct xt_portscan_info *info = matchinfo;
 853 +       enum ip_conntrack_info ctstate;
 854 +       struct nf_conn *ctdata;
 855 +       const struct tcphdr *tcph;
 856 +       struct tcphdr tcph_buf;
 857 +
 858 +       tcph = skb_header_pointer(skb, protoff, sizeof(tcph_buf), &tcph_buf);
 859 +       if(tcph == NULL)
 860 +               return 0;
 861 +
 862 +       /* Check for invalid packets: -m conntrack --ctstate INVALID */
 863 +       if((ctdata = nf_ct_get(skb, &ctstate)) == NULL) {
 864 +               if(info->match_stealth)
 865 +                       return xt_portscan_stealth(tcph);
 866 +               /*
 867 +                * If @ctdata is NULL, we cannot match the other scan
 868 +                * types, return.
 869 +                */
 870 +               return 0;
 871 +       }
 872 +
 873 +       /*
 874 +        * If -m portscan was previously applied to this packet, the rules we
 875 +        * simulate must not be run through again. And for speedup, do not call
 876 +        * it either when the connection is already VALID.
 877 +        */
 878 +       if((ctdata->mark & connmark_mask) == mark_valid ||
 879 +         (skb->nfmark & packet_mask) != mark_seen)
 880 +       {
 881 +               unsigned int n;
 882 +               n = xt_portscan_full(ctdata->mark & connmark_mask, ctstate,
 883 +                   in == &loopback_dev, tcph,
 884 +                   skb->len - protoff - 4 * tcph->doff);
 885 +
 886 +               ctdata->mark = (ctdata->mark & ~connmark_mask) | n;
 887 +               ((struct sk_buff *)skb)->nfmark =
 888 +                       (skb->nfmark & ~packet_mask) | mark_seen;
 889 +       }
 890 +
 891 +       return (info->match_syn && ctdata->mark == mark_synscan) ||
 892 +              (info->match_cn && ctdata->mark == mark_cnscan) ||
 893 +              (info->match_gr && ctdata->mark == mark_grscan);
 894 +}
 895 +
 896 +static int xt_portscan_checkentry(const char *tablename, const void *entry,
 897 +    const struct xt_match *match, void *matchinfo,
 898 +#ifdef HAVE_MATCHINFOSIZE
 899 +    unsigned int matchinfosize,
 900 +#endif
 901 +    unsigned int hook_mask)
 902 +{
 903 +       const struct xt_portscan_info *info = matchinfo;
 904 +#ifdef HAVE_MATCHINFOSIZE
 905 +       if(matchinfosize != XT_ALIGN(sizeof(struct xt_portscan_info))) {
 906 +               printk(KERN_WARNING PFX "matchinfosize %u != %Zu\n",
 907 +                      matchinfosize,
 908 +                      XT_ALIGN(sizeof(struct xt_portscan_info)));
 909 +               return 0;
 910 +       }
 911 +#endif
 912 +       if((info->match_stealth & ~1) || (info->match_syn & ~1) ||
 913 +         (info->match_cn & ~1) || (info->match_gr & ~1)) {
 914 +               printk(KERN_WARNING PFX "Invalid flags\n");
 915 +               return 0;
 916 +       }
 917 +       return 1;
 918 +}
 919 +
 920 +static struct xt_match xt_portscan = {
 921 +       .name       = "portscan",
 922 +       .match      = xt_portscan_match,
 923 +       .checkentry = xt_portscan_checkentry,
 924 +       .matchsize  = sizeof(struct xt_portscan_info),
 925 +       .proto      = IPPROTO_TCP,
 926 +       .family     = AF_INET,
 927 +       .me         = THIS_MODULE,
 928 +};
 929 +
 930 +static int __init xt_portscan_init(void)
 931 +{
 932 +       return xt_register_match(&xt_portscan);
 933 +}
 934 +
 935 +static void __exit xt_portscan_exit(void)
 936 +{
 937 +       xt_unregister_match(&xt_portscan);
 938 +       return;
 939 +}
 940 +
 941 +module_init(xt_portscan_init);
 942 +module_exit(xt_portscan_exit);
 943 +MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
 944 +MODULE_DESCRIPTION("netfilter portscan match module");
 945 +MODULE_LICENSE("GPL");
 946 +MODULE_ALIAS("ipt_portscan");
 947 diff -urN linux-2.6.22-rc3.old/drivers/char/random.c linux-2.6.22-rc3.dev/drivers/char/random.c
 948 --- linux-2.6.22-rc3.old/drivers/char/random.c  2007-05-26 03:55:14.000000000 +0100
 949 +++ linux-2.6.22-rc3.dev/drivers/char/random.c  2007-05-29 11:21:53.000000000 +0100
 950 @@ -1557,6 +1557,8 @@
 951         return seq;
 952  }
 953
 954 +EXPORT_SYMBOL(secure_tcp_sequence_number);
 955 +
 956  /* Generate secure starting point for ephemeral IPV4 transport port search */
 957  u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
 958  {