--- /dev/null
+diff -ruN linux-2.6.19.1.orig/include/linux/netfilter/xt_CHAOS.h linux-2.6.19.1/include/linux/netfilter/xt_CHAOS.h
+--- linux-2.6.19.1.orig/include/linux/netfilter/xt_CHAOS.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/include/linux/netfilter/xt_CHAOS.h 2007-01-11 13:28:07.656144799 +0100
+@@ -0,0 +1,14 @@
++#ifndef _LINUX_XT_CHAOS_H
++#define _LINUX_XT_CHAOS_H 1
++
++enum xt_chaos_variant {
++ XTCHAOS_NORMAL,
++ XTCHAOS_TARPIT,
++ XTCHAOS_DELUDE,
++};
++
++struct xt_chaos_info {
++ enum xt_chaos_variant variant;
++};
++
++#endif /* _LINUX_XT_CHAOS_H */
+diff -ruN linux-2.6.19.1.orig/include/linux/netfilter/xt_portscan.h linux-2.6.19.1/include/linux/netfilter/xt_portscan.h
+--- linux-2.6.19.1.orig/include/linux/netfilter/xt_portscan.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/include/linux/netfilter/xt_portscan.h 2007-01-11 13:28:07.656144799 +0100
+@@ -0,0 +1,8 @@
++#ifndef _LINUX_XT_PORTSCAN_H
++#define _LINUX_XT_PORTSCAN_H 1
++
++struct xt_portscan_info {
++ unsigned int match_stealth, match_syn, match_cn, match_gr;
++};
++
++#endif /* _LINUX_XT_PORTSCAN_H */
+diff -ruN linux-2.6.19.1.orig/net/netfilter/find_match.c linux-2.6.19.1/net/netfilter/find_match.c
+--- linux-2.6.19.1.orig/net/netfilter/find_match.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/net/netfilter/find_match.c 2007-01-11 13:28:12.191994379 +0100
+@@ -0,0 +1,37 @@
++/*
++ xt_request_find_match
++ by Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
++
++ Based upon linux-2.6.18.5/net/netfilter/x_tables.c:
++ Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
++ This program is free software; you can redistribute it and/or modify
++ it under the terms of the GNU General Public License version 2 as
++ published by the Free Software Foundation.
++*/
++
++#include <linux/err.h>
++#include <linux/netfilter_arp.h>
++#include <linux/socket.h>
++#include <linux/netfilter/x_tables.h>
++
++/*
++ * Yeah this code is sub-optimal, but the function is missing in
++ * mainline so far. -jengelh
++ */
++static struct xt_match *xt_request_find_match(int af, const char *name,
++ u8 revision)
++{
++ static const char *const xt_prefix[] = {
++ [AF_INET] = "ip",
++ [AF_INET6] = "ip6",
++ [NF_ARP] = "arp",
++ };
++ struct xt_match *match;
++
++ match = try_then_request_module(xt_find_match(af, name, revision),
++ "%st_%s", xt_prefix[af], name);
++ if(IS_ERR(match) || match == NULL)
++ return NULL;
++
++ return match;
++}
+diff -ruN linux-2.6.19.1.orig/net/netfilter/Kconfig linux-2.6.19.1/net/netfilter/Kconfig
+--- linux-2.6.19.1.orig/net/netfilter/Kconfig 2007-01-11 13:27:24.445577700 +0100
++++ linux-2.6.19.1/net/netfilter/Kconfig 2007-01-11 13:28:09.092097179 +0100
+@@ -122,6 +122,14 @@
+
+ # alphabetically ordered list of targets
+
++config NETFILTER_XT_TARGET_CHAOS
++ tristate '"CHAOS" target support'
++ depends on NETFILTER_XTABLES
++ help
++ This option adds a `CHAOS' target.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_TARGET_CLASSIFY
+ tristate '"CLASSIFY" target support'
+ depends on NETFILTER_XTABLES
+@@ -148,6 +156,14 @@
+ <file:Documentation/modules.txt>. The module will be called
+ ipt_CONNMARK.o. If unsure, say `N'.
+
++config NETFILTER_XT_TARGET_DELUDE
++ tristate '"DELUDE" target support'
++ depends on NETFILTER_XTABLES
++ help
++ This option adds a `DELUDE' target.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_TARGET_DSCP
+ tristate '"DSCP" target support'
+ depends on NETFILTER_XTABLES
+@@ -355,6 +371,14 @@
+
+ To compile it as a module, choose M here. If unsure, say N.
+
++config NETFILTER_XT_MATCH_PORTSCAN
++ tristate '"portscan" match support'
++ depends on NETFILTER_XTABLES
++ help
++ This option adds a 'portscan' match support.
++
++ To compile it as a module, choose M here. If unsure, say N.
++
+ config NETFILTER_XT_MATCH_MULTIPORT
+ tristate "Multiple port match support"
+ depends on NETFILTER_XTABLES
+diff -ruN linux-2.6.19.1.orig/net/netfilter/Makefile linux-2.6.19.1/net/netfilter/Makefile
+--- linux-2.6.19.1.orig/net/netfilter/Makefile 2007-01-11 13:27:24.445577700 +0100
++++ linux-2.6.19.1/net/netfilter/Makefile 2007-01-11 13:28:07.656144799 +0100
+@@ -23,8 +23,10 @@
+ obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o
+
+ # targets
++obj-$(CONFIG_NETFILTER_XT_TARGET_CHAOS) += xt_CHAOS.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_CLASSIFY) += xt_CLASSIFY.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_CONNMARK) += xt_CONNMARK.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_DELUDE) += xt_DELUDE.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_MARK) += xt_MARK.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
+@@ -47,6 +49,7 @@
+ obj-$(CONFIG_NETFILTER_XT_MATCH_MARK) += xt_mark.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_MULTIPORT) += xt_multiport.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o
++obj-$(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) += xt_portscan.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA) += xt_quota.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
+diff -ruN linux-2.6.19.1.orig/net/netfilter/xt_CHAOS.c linux-2.6.19.1/net/netfilter/xt_CHAOS.c
+--- linux-2.6.19.1.orig/net/netfilter/xt_CHAOS.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/net/netfilter/xt_CHAOS.c 2007-01-11 13:28:14.407920893 +0100
+@@ -0,0 +1,180 @@
++/*
++ CHAOS target for netfilter
++
++ Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
++ released under the terms of the GNU General Public
++ License version 2.x and only versions 2.x.
++*/
++#include <linux/icmp.h>
++#include <linux/in.h>
++#include <linux/ip.h>
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/stat.h>
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_tcpudp.h>
++#include <linux/netfilter_ipv4/ipt_REJECT.h>
++#include <net/ip.h>
++#include <linux/netfilter/xt_CHAOS.h>
++#include "find_match.c"
++#define PFX KBUILD_MODNAME ": "
++
++/* Out of tree workarounds */
++#include <linux/version.h>
++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
++# define HAVE_TARGUSERINFO 1
++#endif
++
++/* Module parameters */
++static unsigned int reject_percentage = ~0U * .01;
++static unsigned int delude_percentage = ~0U * .0101;
++module_param(reject_percentage, uint, S_IRUGO | S_IWUSR);
++module_param(delude_percentage, uint, S_IRUGO | S_IWUSR);
++
++/* References to other matches/targets */
++static struct xt_match *xm_tcp;
++static struct xt_target *xt_delude, *xt_reject, *xt_tarpit;
++
++/* Static data for other matches/targets */
++static const struct ipt_reject_info reject_params = {
++ .with = ICMP_HOST_UNREACH,
++};
++
++static const struct xt_tcp tcp_params = {
++ .spts = {0, ~0},
++ .dpts = {0, ~0},
++};
++
++/* CHAOS functions */
++static void xt_chaos_total(const struct xt_chaos_info *info,
++ struct sk_buff **pskb, const struct net_device *in,
++ const struct net_device *out, unsigned int hooknum)
++{
++ const int protoff = 4 * (*pskb)->nh.iph->ihl;
++ const int offset = ntohs((*pskb)->nh.iph->frag_off) & IP_OFFSET;
++ const struct xt_target *destiny;
++ int hotdrop = 0, ret;
++
++ ret = xm_tcp->match(*pskb, in, out, xm_tcp, &tcp_params,
++ offset, protoff, &hotdrop);
++ if(!ret || hotdrop || (unsigned int)net_random() > delude_percentage)
++ return;
++
++ destiny = (info->variant == XTCHAOS_TARPIT) ? xt_tarpit : xt_delude;
++#ifdef HAVE_TARGUSERINFO
++ destiny->target(pskb, in, out, hooknum, destiny, NULL, NULL);
++#else
++ destiny->target(pskb, in, out, hooknum, destiny, NULL);
++#endif
++ return;
++}
++
++static unsigned int xt_chaos_target(struct sk_buff **pskb,
++ const struct net_device *in, const struct net_device *out,
++ unsigned int hooknum, const struct xt_target *target, const void *targinfo
++#ifdef HAVE_TARGUSERINFO
++ ,
++ void *userinfo
++#endif
++ )
++{
++ /* Equivalent to:
++ * -A chaos -m statistic --mode random --probability \
++ * $reject_percentage -j REJECT --reject-with host-unreach;
++ * -A chaos -m statistic --mode random --probability \
++ * $delude_percentage -j DELUDE;
++ * -A chaos -j DROP;
++ */
++ const struct xt_chaos_info *info = targinfo;
++
++ if((unsigned int)net_random() <= reject_percentage)
++#ifdef HAVE_TARGUSERINFO
++ return xt_reject->target(pskb, in, out, hooknum, target,
++ &reject_params, userinfo);
++#else
++ return xt_reject->target(pskb, in, out, hooknum, target,
++ &reject_params);
++#endif
++
++ /* TARPIT/DELUDE may not be called from the OUTPUT chain */
++ if((*pskb)->nh.iph->protocol == IPPROTO_TCP &&
++ info->variant != XTCHAOS_NORMAL && hooknum != NF_IP_LOCAL_OUT)
++ xt_chaos_total(info, pskb, in, out, hooknum);
++
++ return NF_DROP;
++}
++
++static struct xt_target xt_chaos_info = {
++ .name = "CHAOS",
++ .target = xt_chaos_target,
++ .table = "filter",
++ .targetsize = sizeof(struct xt_chaos_info),
++ .hooks = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) |
++ (1 << NF_IP_LOCAL_OUT),
++ .family = AF_INET,
++ .me = THIS_MODULE,
++};
++
++static int __init xt_chaos_init(void)
++{
++ int ret = -EINVAL;
++
++ xm_tcp = xt_request_find_match(AF_INET, "tcp", 0);
++ if(xm_tcp == NULL) {
++ printk(KERN_WARNING PFX "Could not find \"tcp\" match\n");
++ return -EINVAL;
++ }
++
++ xt_reject = xt_request_find_target(AF_INET, "REJECT", 0);
++ if(xt_reject == NULL) {
++ printk(KERN_WARNING PFX "Could not find \"REJECT\" target\n");
++ goto out2;
++ }
++
++ xt_tarpit = xt_request_find_target(AF_INET, "TARPIT", 0);
++ if(xt_tarpit == NULL) {
++ printk(KERN_WARNING PFX "Could not find \"TARPIT\" target\n");
++ goto out3;
++ }
++
++ xt_delude = xt_request_find_target(AF_INET, "DELUDE", 0);
++ if(xt_delude == NULL) {
++ printk(KERN_WARNING PFX "Could not find \"DELUDE\" target\n");
++ goto out4;
++ }
++
++ if((ret = xt_register_target(&xt_chaos_info)) != 0) {
++ printk(KERN_WARNING PFX "xt_register_target returned "
++ "error %d\n", ret);
++ goto out5;
++ }
++
++ return 0;
++
++ out5:
++ module_put(xt_delude->me);
++ out4:
++ module_put(xt_tarpit->me);
++ out3:
++ module_put(xt_reject->me);
++ out2:
++ module_put(xm_tcp->me);
++ return ret;
++}
++
++static void __exit xt_chaos_exit(void)
++{
++ xt_unregister_target(&xt_chaos_info);
++ module_put(xm_tcp->me);
++ module_put(xt_reject->me);
++ module_put(xt_delude->me);
++ module_put(xt_tarpit->me);
++ return;
++}
++
++module_init(xt_chaos_init);
++module_exit(xt_chaos_exit);
++MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
++MODULE_DESCRIPTION("netfilter CHAOS target");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_CHAOS");
+diff -ruN linux-2.6.19.1.orig/net/netfilter/xt_DELUDE.c linux-2.6.19.1/net/netfilter/xt_DELUDE.c
+--- linux-2.6.19.1.orig/net/netfilter/xt_DELUDE.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/net/netfilter/xt_DELUDE.c 2007-01-11 13:28:07.656144799 +0100
+@@ -0,0 +1,265 @@
++/*
++ DELUDE target
++ Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2007
++
++ Based upon linux-2.6.18.5/net/ipv4/netfilter/ipt_REJECT.c:
++ (C) 1999-2001 Paul `Rusty' Russell
++ (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
++
++ This program is free software; you can redistribute it and/or modify
++ it under the terms of the GNU General Public License version 2 as
++ published by the Free Software Foundation.
++*/
++
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/ip.h>
++#include <linux/tcp.h>
++#include <linux/udp.h>
++#include <linux/icmp.h>
++#include <net/icmp.h>
++#include <net/ip.h>
++#include <net/tcp.h>
++#include <net/route.h>
++#include <net/dst.h>
++#include <linux/netfilter_ipv4/ip_tables.h>
++#ifdef CONFIG_BRIDGE_NETFILTER
++#include <linux/netfilter_bridge.h>
++#endif
++#define PFX KBUILD_MODNAME ": "
++
++/* Out of tree workarounds */
++#include <linux/version.h>
++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
++# define HAVE_TARGINFOSIZE 1
++# define HAVE_TARGUSERINFO 1
++#endif
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
++# define nfmark mark
++#endif
++
++static inline struct rtable *route_reverse(struct sk_buff *skb,
++ struct tcphdr *tcph, int hook)
++{
++ struct iphdr *iph = skb->nh.iph;
++ struct dst_entry *odst;
++ struct flowi fl = {};
++ struct rtable *rt;
++
++ /* We don't require ip forwarding to be enabled to be able to
++ * send a RST reply for bridged traffic. */
++ if (hook != NF_IP_FORWARD
++#ifdef CONFIG_BRIDGE_NETFILTER
++ || (skb->nf_bridge && skb->nf_bridge->mask & BRNF_BRIDGED)
++#endif
++ ) {
++ fl.nl_u.ip4_u.daddr = iph->saddr;
++ if (hook == NF_IP_LOCAL_IN)
++ fl.nl_u.ip4_u.saddr = iph->daddr;
++ fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
++
++ if (ip_route_output_key(&rt, &fl) != 0)
++ return NULL;
++ } else {
++ /* non-local src, find valid iif to satisfy
++ * rp-filter when calling ip_route_input. */
++ fl.nl_u.ip4_u.daddr = iph->daddr;
++ if (ip_route_output_key(&rt, &fl) != 0)
++ return NULL;
++
++ odst = skb->dst;
++ if (ip_route_input(skb, iph->saddr, iph->daddr,
++ RT_TOS(iph->tos), rt->u.dst.dev) != 0) {
++ dst_release(&rt->u.dst);
++ return NULL;
++ }
++ dst_release(&rt->u.dst);
++ rt = (struct rtable *)skb->dst;
++ skb->dst = odst;
++
++ fl.nl_u.ip4_u.daddr = iph->saddr;
++ fl.nl_u.ip4_u.saddr = iph->daddr;
++ fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
++ }
++
++ if (rt->u.dst.error) {
++ dst_release(&rt->u.dst);
++ return NULL;
++ }
++
++ fl.proto = IPPROTO_TCP;
++ fl.fl_ip_sport = tcph->dest;
++ fl.fl_ip_dport = tcph->source;
++
++ xfrm_lookup((struct dst_entry **)&rt, &fl, NULL, 0);
++
++ return rt;
++}
++
++static void send_reset(struct sk_buff *oldskb, int hook)
++{
++ struct sk_buff *nskb;
++ struct iphdr *iph = oldskb->nh.iph;
++ struct tcphdr _otcph, *oth, *tcph;
++ struct rtable *rt;
++ u_int16_t tmp_port;
++ u_int32_t tmp_addr;
++ int hh_len;
++
++ /* IP header checks: fragment. */
++ if (oldskb->nh.iph->frag_off & htons(IP_OFFSET))
++ return;
++
++ oth = skb_header_pointer(oldskb, oldskb->nh.iph->ihl * 4,
++ sizeof(_otcph), &_otcph);
++ if (oth == NULL)
++ return;
++
++ /* DELUDE only answers SYN. */
++ if(!oth->syn || oth->ack || oth->fin || oth->rst)
++ return;
++
++ /* Check checksum */
++ if (nf_ip_checksum(oldskb, hook, iph->ihl * 4, IPPROTO_TCP))
++ return;
++
++ if ((rt = route_reverse(oldskb, oth, hook)) == NULL)
++ return;
++
++ hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
++
++ /* We need a linear, writeable skb. We also need to expand
++ headroom in case hh_len of incoming interface < hh_len of
++ outgoing interface */
++ nskb = skb_copy_expand(oldskb, hh_len, skb_tailroom(oldskb),
++ GFP_ATOMIC);
++ if (!nskb) {
++ dst_release(&rt->u.dst);
++ return;
++ }
++
++ dst_release(nskb->dst);
++ nskb->dst = &rt->u.dst;
++
++ /* This packet will not be the same as the other: clear nf fields */
++ nf_reset(nskb);
++ nskb->nfmark = 0;
++ skb_init_secmark(nskb);
++
++ tcph = (struct tcphdr *)((u_int32_t*)nskb->nh.iph + nskb->nh.iph->ihl);
++
++ /* Swap source and dest */
++ tmp_addr = nskb->nh.iph->saddr;
++ nskb->nh.iph->saddr = nskb->nh.iph->daddr;
++ nskb->nh.iph->daddr = tmp_addr;
++ tmp_port = tcph->source;
++ tcph->source = tcph->dest;
++ tcph->dest = tmp_port;
++
++ /* Truncate to length (no data) */
++ tcph->doff = sizeof(struct tcphdr)/4;
++ skb_trim(nskb, nskb->nh.iph->ihl*4 + sizeof(struct tcphdr));
++ nskb->nh.iph->tot_len = htons(nskb->len);
++
++ tcph->seq = oth->ack_seq;
++ tcph->ack_seq = 0;
++
++ /* Reset flags */
++ ((u_int8_t *)tcph)[13] = 0;
++ tcph->syn = tcph->ack = 1;
++
++ tcph->window = 0;
++ tcph->urg_ptr = 0;
++
++ /* Adjust TCP checksum */
++ tcph->check = 0;
++ tcph->check = tcp_v4_check(tcph, sizeof(struct tcphdr),
++ nskb->nh.iph->saddr,
++ nskb->nh.iph->daddr,
++ csum_partial((char *)tcph,
++ sizeof(struct tcphdr), 0));
++
++ /* Adjust IP TTL, DF */
++ nskb->nh.iph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
++ /* Set DF, id = 0 */
++ nskb->nh.iph->frag_off = htons(IP_DF);
++ nskb->nh.iph->id = 0;
++
++ /* Adjust IP checksum */
++ nskb->nh.iph->check = 0;
++ nskb->nh.iph->check = ip_fast_csum((unsigned char *)nskb->nh.iph,
++ nskb->nh.iph->ihl);
++
++ /* "Never happens" */
++ if (nskb->len > dst_mtu(nskb->dst))
++ goto free_nskb;
++
++ nf_ct_attach(nskb, oldskb);
++
++ NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
++ dst_output);
++ return;
++
++ free_nskb:
++ kfree_skb(nskb);
++ return;
++}
++
++static unsigned int xt_delude_target(struct sk_buff **pskb,
++ const struct net_device *in, const struct net_device *out,
++ unsigned int hooknum, const struct xt_target *target, const void *targinfo
++#ifdef HAVE_TARGUSERINFO
++ ,
++ void *userinfo
++#endif
++ )
++{
++ /* WARNING: This code causes reentry within iptables.
++ This means that the iptables jump stack is now crap. We
++ must return an absolute verdict. --RR */
++ send_reset(*pskb, hooknum);
++ return NF_DROP;
++}
++
++static int xt_delude_check(const char *tablename, const void *e_void,
++ const struct xt_target *target, void *targinfo,
++#ifdef HAVE_TARGINFOSIZE
++ unsigned int targinfosize,
++#endif
++ unsigned int hook_mask)
++{
++ if(hook_mask & ~((1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD))) {
++ printk(KERN_WARNING PFX "DELUDE may not be used in chains "
++ "other than INPUT and FORWARD\n");
++ return 0;
++ }
++ return 1;
++}
++
++static struct xt_target xt_delude_info = {
++ .name = "DELUDE",
++ .target = xt_delude_target,
++ .checkentry = xt_delude_check,
++ .table = "filter",
++ .hooks = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) |
++ (1 << NF_IP_LOCAL_OUT),
++ .proto = IPPROTO_TCP,
++ .family = AF_INET,
++ .me = THIS_MODULE,
++};
++
++static int __init xt_delude_init(void)
++{
++ return xt_register_target(&xt_delude_info);
++}
++
++static void __exit xt_delude_exit(void)
++{
++ xt_unregister_target(&xt_delude_info);
++}
++
++module_init(xt_delude_init);
++module_exit(xt_delude_exit);
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
++MODULE_DESCRIPTION("netfilter DELUDE target");
+diff -ruN linux-2.6.19.1.orig/net/netfilter/xt_portscan.c linux-2.6.19.1/net/netfilter/xt_portscan.c
+--- linux-2.6.19.1.orig/net/netfilter/xt_portscan.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.19.1/net/netfilter/xt_portscan.c 2007-01-11 13:28:14.407920893 +0100
+@@ -0,0 +1,282 @@
++/*
++ portscan match for netfilter
++
++ Written by Jan Engelhardt, 2006 - 2007
++ released under the terms of the GNU General Public
++ License version 2.x and only versions 2.x.
++*/
++#include <linux/in.h>
++#include <linux/ip.h>
++#include <linux/module.h>
++#include <linux/moduleparam.h>
++#include <linux/skbuff.h>
++#include <linux/stat.h>
++#include <linux/tcp.h>
++#include <linux/types.h>
++#include <linux/version.h>
++#include <linux/netfilter/x_tables.h>
++#include <linux/netfilter/xt_tcpudp.h>
++#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
++# include <linux/netfilter_ipv4/ip_conntrack.h>
++#else /* linux-2.6.20+ */
++# include <net/netfilter/nf_nat_rule.h>
++#endif
++#include <linux/netfilter/xt_portscan.h>
++#define PFX KBUILD_MODNAME ": "
++
++/* Out of tree workarounds */
++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
++# define HAVE_MATCHINFOSIZE 1
++#endif
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
++# define nfmark mark
++#endif
++
++enum {
++ TCP_FLAGS_ALL3 = TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_SYN,
++ TCP_FLAGS_ALL4 = TCP_FLAGS_ALL3 | TCP_FLAG_ACK,
++ TCP_FLAGS_ALL6 = TCP_FLAGS_ALL4 | TCP_FLAG_PSH | TCP_FLAG_URG,
++};
++
++/* Module parameters */
++static unsigned int
++ connmark_mask = ~0,
++ packet_mask = ~0,
++ mark_seen = 0x9,
++ mark_synrcv = 0x1,
++ mark_closed = 0x2,
++ mark_synscan = 0x3,
++ mark_estab1 = 0x4,
++ mark_estab2 = 0x5,
++ mark_cnscan = 0x6,
++ mark_grscan = 0x7,
++ mark_valid = 0x8;
++
++module_param(connmark_mask, uint, S_IRUGO | S_IWUSR);
++module_param(packet_mask, uint, S_IRUGO | S_IWUSR);
++module_param(mark_seen, uint, S_IRUGO | S_IWUSR);
++module_param(mark_synrcv, uint, S_IRUGO | S_IWUSR);
++module_param(mark_closed, uint, S_IRUGO | S_IWUSR);
++module_param(mark_synscan, uint, S_IRUGO | S_IWUSR);
++module_param(mark_estab1, uint, S_IRUGO | S_IWUSR);
++module_param(mark_estab2, uint, S_IRUGO | S_IWUSR);
++module_param(mark_cnscan, uint, S_IRUGO | S_IWUSR);
++module_param(mark_grscan, uint, S_IRUGO | S_IWUSR);
++module_param(mark_valid, uint, S_IRUGO | S_IWUSR);
++MODULE_PARM_DESC(connmark_mask, "only set specified bits in connection mark");
++MODULE_PARM_DESC(packet_mask, "only set specified bits in packet mark");
++MODULE_PARM_DESC(mark_seen, "nfmark value for packet-seen state");
++MODULE_PARM_DESC(mark_synrcv, "connmark value for SYN Received state");
++MODULE_PARM_DESC(mark_closed, "connmark value for closed state");
++MODULE_PARM_DESC(mark_synscan, "connmark value for SYN Scan state");
++MODULE_PARM_DESC(mark_estab1, "connmark value for Established-1 state");
++MODULE_PARM_DESC(mark_estab2, "connmark value for Established-2 state");
++MODULE_PARM_DESC(mark_cnscan, "connmark value for Connect Scan state");
++MODULE_PARM_DESC(mark_grscan, "connmark value for Grab Scan state");
++MODULE_PARM_DESC(mark_valid, "connmark value for Valid state");
++
++/* TCP flag functions */
++static inline int tflg_ack4(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_ACK;
++}
++
++static inline int tflg_ack6(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL6) == TCP_FLAG_ACK;
++}
++
++static inline int tflg_fin(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_FIN;
++}
++
++static inline int tflg_rst(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_RST;
++}
++
++static inline int tflg_rstack(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
++ (TCP_FLAG_ACK | TCP_FLAG_RST);
++}
++
++static inline int tflg_syn(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_SYN;
++}
++
++static inline int tflg_synack(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
++ (TCP_FLAG_SYN | TCP_FLAG_ACK);
++}
++
++/* portscan functions */
++static inline int xt_portscan_stealth(const struct tcphdr *th)
++{
++ /*
++ * "Connection refused" replies to our own probes must not be matched.
++ */
++ if(tflg_rstack(th))
++ return 0;
++
++ if(tflg_rst(th) && printk_ratelimit()) {
++ printk(KERN_WARNING PFX "Warning: Pure RST received\n");
++ return 0;
++ }
++
++ /*
++ * -p tcp ! --syn -m conntrack --ctstate INVALID: Looking for non-start
++ * packets that are not associated with any connection -- this will
++ * match most scan types (NULL, XMAS, FIN) and ridiculous flag
++ * combinations (SYN-RST, SYN-FIN, SYN-FIN-RST, FIN-RST, etc.).
++ */
++ return !tflg_syn(th);
++}
++
++static inline int xt_portscan_full(int mark, enum ip_conntrack_info ctstate,
++ int loopback, const struct tcphdr *tcph, int payload_len)
++{
++ if(mark == mark_estab2) {
++ /*
++ * -m connmark --mark $ESTAB2
++ */
++ if(tflg_ack4(tcph) && payload_len == 0)
++ return mark; /* keep mark */
++ else if(tflg_rst(tcph) || tflg_fin(tcph))
++ return mark_grscan;
++ else
++ return mark_valid;
++ } else if(mark == mark_estab1) {
++ /*
++ * -m connmark --mark $ESTAB1
++ */
++ if(tflg_rst(tcph) || tflg_fin(tcph))
++ return mark_cnscan;
++ else if(!loopback && tflg_ack4(tcph) && payload_len == 0)
++ return mark_estab2;
++ else
++ return mark_valid;
++ } else if(mark == mark_synrcv) {
++ /*
++ * -m connmark --mark $SYN
++ */
++ if(loopback && tflg_synack(tcph))
++ return mark; /* keep mark */
++ else if(loopback && tflg_rstack(tcph))
++ return mark_closed;
++ else if(tflg_ack6(tcph))
++ return mark_estab1;
++ else
++ return mark_synscan;
++ } else if(ctstate == IP_CT_NEW && tflg_syn(tcph)) {
++ /*
++ * -p tcp --syn --ctstate NEW
++ */
++ return mark_synrcv;
++ }
++ return mark;
++}
++
++static int xt_portscan_match(const struct sk_buff *skb,
++ const struct net_device *in, const struct net_device *out,
++ const struct xt_match *match, const void *matchinfo, int offset,
++ unsigned int protoff, int *hotdrop)
++{
++ const struct xt_portscan_info *info = matchinfo;
++ enum ip_conntrack_info ctstate;
++ struct ip_conntrack *ctdata;
++ const struct tcphdr *tcph;
++ struct tcphdr tcph_buf;
++
++ tcph = skb_header_pointer(skb, protoff, sizeof(tcph_buf), &tcph_buf);
++ if(tcph == NULL)
++ return 0;
++
++ /* Check for invalid packets: -m conntrack --ctstate INVALID */
++ if((ctdata = ip_conntrack_get(skb, &ctstate)) == NULL) {
++ if(info->match_stealth)
++ return xt_portscan_stealth(tcph);
++ /*
++ * If @ctdata is NULL, we cannot match the other scan
++ * types, return.
++ */
++ return 0;
++ }
++
++ /*
++ * If -m portscan was previously applied to this packet, the rules we
++ * simulate must not be run through again. And for speedup, do not call
++ * it either when the connection is already VALID.
++ */
++ if((ctdata->mark & connmark_mask) == mark_valid ||
++ (skb->nfmark & packet_mask) != mark_seen)
++ {
++ unsigned int n;
++ n = xt_portscan_full(ctdata->mark & connmark_mask, ctstate,
++ in == &loopback_dev, tcph,
++ skb->len - protoff - 4 * tcph->doff);
++
++ ctdata->mark = (ctdata->mark & ~connmark_mask) | n;
++ ((struct sk_buff *)skb)->nfmark =
++ (skb->nfmark & ~packet_mask) | mark_seen;
++ }
++
++ return (info->match_syn && ctdata->mark == mark_synscan) ||
++ (info->match_cn && ctdata->mark == mark_cnscan) ||
++ (info->match_gr && ctdata->mark == mark_grscan);
++}
++
++static int xt_portscan_checkentry(const char *tablename, const void *entry,
++ const struct xt_match *match, void *matchinfo,
++#ifdef HAVE_MATCHINFOSIZE
++ unsigned int matchinfosize,
++#endif
++ unsigned int hook_mask)
++{
++ const struct xt_portscan_info *info = matchinfo;
++#ifdef HAVE_MATCHINFOSIZE
++ if(matchinfosize != XT_ALIGN(sizeof(struct xt_portscan_info))) {
++ printk(KERN_WARNING PFX "matchinfosize %u != %Zu\n",
++ matchinfosize,
++ XT_ALIGN(sizeof(struct xt_portscan_info)));
++ return 0;
++ }
++#endif
++ if((info->match_stealth & ~1) || (info->match_syn & ~1) ||
++ (info->match_cn & ~1) || (info->match_gr & ~1)) {
++ printk(KERN_WARNING PFX "Invalid flags\n");
++ return 0;
++ }
++ return 1;
++}
++
++static struct xt_match xt_portscan = {
++ .name = "portscan",
++ .match = xt_portscan_match,
++ .checkentry = xt_portscan_checkentry,
++ .matchsize = sizeof(struct xt_portscan_info),
++ .proto = IPPROTO_TCP,
++ .family = AF_INET,
++ .me = THIS_MODULE,
++};
++
++static int __init xt_portscan_init(void)
++{
++ return xt_register_match(&xt_portscan);
++}
++
++static void __exit xt_portscan_exit(void)
++{
++ xt_unregister_match(&xt_portscan);
++ return;
++}
++
++module_init(xt_portscan_init);
++module_exit(xt_portscan_exit);
++MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
++MODULE_DESCRIPTION("netfilter portscan match module");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_portscan");
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