--- /dev/null
+Index: linux-2.6.24/include/linux/netfilter/oot_conntrack.h
+===================================================================
+--- /dev/null
++++ linux-2.6.24/include/linux/netfilter/oot_conntrack.h
+@@ -0,0 +1,5 @@
++#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
+Index: linux-2.6.24/include/linux/netfilter/oot_trans.h
+===================================================================
+--- /dev/null
++++ linux-2.6.24/include/linux/netfilter/oot_trans.h
+@@ -0,0 +1,14 @@
++/* Out of tree workarounds */
++#include <linux/version.h>
++#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
++# define HAVE_MATCHINFOSIZE 1
++# define HAVE_TARGUSERINFO 1
++# define HAVE_TARGINFOSIZE 1
++#endif
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
++# define nfmark mark
++#endif
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 21)
++# define tcp_v4_check(tcph, tcph_sz, s, d, csp) \
++ tcp_v4_check((tcph_sz), (s), (d), (csp))
++#endif
+Index: linux-2.6.24/include/linux/netfilter/xt_CHAOS.h
+===================================================================
+--- /dev/null
++++ linux-2.6.24/include/linux/netfilter/xt_CHAOS.h
+@@ -0,0 +1,14 @@
++#ifndef _LINUX_NETFILTER_XT_CHAOS_H
++#define _LINUX_NETFILTER_XT_CHAOS_H 1
++
++enum xt_chaos_target_variant {
++ XTCHAOS_NORMAL,
++ XTCHAOS_TARPIT,
++ XTCHAOS_DELUDE,
++};
++
++struct xt_chaos_target_info {
++ uint8_t variant;
++};
++
++#endif /* _LINUX_NETFILTER_XT_CHAOS_H */
+Index: linux-2.6.24/include/linux/netfilter/xt_portscan.h
+===================================================================
+--- /dev/null
++++ linux-2.6.24/include/linux/netfilter/xt_portscan.h
+@@ -0,0 +1,8 @@
++#ifndef _LINUX_NETFILTER_XT_PORTSCAN_H
++#define _LINUX_NETFILTER_XT_PORTSCAN_H 1
++
++struct xt_portscan_match_info {
++ uint8_t match_stealth, match_syn, match_cn, match_gr;
++};
++
++#endif /* _LINUX_NETFILTER_XT_PORTSCAN_H */
+Index: linux-2.6.24/net/netfilter/find_match.c
+===================================================================
+--- /dev/null
++++ linux-2.6.24/net/netfilter/find_match.c
+@@ -0,0 +1,39 @@
++/*
++ 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_lo(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;
++}
++
++/* In case it goes into mainline, let this out-of-tree package compile */
++#define xt_request_find_match xt_request_find_match_lo
+Index: linux-2.6.24/net/netfilter/Kconfig
+===================================================================
+--- linux-2.6.24.orig/net/netfilter/Kconfig
++++ linux-2.6.24/net/netfilter/Kconfig
+@@ -265,6 +265,14 @@ config NETFILTER_XTABLES
+
+ # 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
+@@ -292,6 +300,14 @@ config NETFILTER_XT_TARGET_CONNMARK
+ <file:Documentation/kbuild/modules.txt>. The module will be called
+ ipt_CONNMARK.ko. 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
+@@ -556,6 +572,14 @@ config NETFILTER_XT_MATCH_POLICY
+
+ 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
+Index: linux-2.6.24/net/netfilter/Makefile
+===================================================================
+--- linux-2.6.24.orig/net/netfilter/Makefile
++++ linux-2.6.24/net/netfilter/Makefile
+@@ -49,6 +49,8 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_NOTRACK
+ obj-$(CONFIG_NETFILTER_XT_TARGET_SECMARK) += xt_SECMARK.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o
+ obj-$(CONFIG_NETFILTER_XT_TARGET_TRACE) += xt_TRACE.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_CHAOS) += xt_CHAOS.o
++obj-$(CONFIG_NETFILTER_XT_TARGET_DELUDE) += xt_DELUDE.o
+
+ # matches
+ obj-$(CONFIG_NETFILTER_XT_MATCH_COMMENT) += xt_comment.o
+@@ -79,3 +81,4 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_STRING)
+ obj-$(CONFIG_NETFILTER_XT_MATCH_TCPMSS) += xt_tcpmss.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_TIME) += xt_time.o
+ obj-$(CONFIG_NETFILTER_XT_MATCH_U32) += xt_u32.o
++obj-$(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) += xt_portscan.o
+Index: linux-2.6.24/net/netfilter/xt_CHAOS.c
+===================================================================
+--- /dev/null
++++ linux-2.6.24/net/netfilter/xt_CHAOS.c
+@@ -0,0 +1,200 @@
++/*
++ * CHAOS target for netfilter
++ * Copyright © CC Computer Consultants GmbH, 2006 - 2007
++ * Contact: Jan Engelhardt <jengelh@computergmbh.de>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License; either version
++ * 2 or 3 as published by the Free Software Foundation.
++ */
++#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>
++#if defined(_LOCAL)
++# include "xt_CHAOS.h"
++# include "find_match.c"
++#elif defined(CONFIG_NETFILTER_XT_TARGET_CHAOS) || \
++ defined(CONFIG_NETFILTER_XT_TARGET_CHAOS_MODULE)
++# include <linux/netfilter/xt_CHAOS.h>
++# include "find_match.c"
++#else
++# include "xt_CHAOS.h"
++# include "find_match.c"
++#endif
++#define PFX KBUILD_MODNAME ": "
++
++/* 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 int have_delude, have_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_target_info *info,
++ struct sk_buff *skb, const struct net_device *in,
++ const struct net_device *out, unsigned int hooknum)
++{
++ const struct iphdr *iph = ip_hdr(skb);
++ const int protoff = 4 * iph->ihl;
++ const int offset = ntohs(iph->frag_off) & IP_OFFSET;
++ const struct xt_target *destiny;
++ bool hotdrop = false, ret;
++
++ ret = xm_tcp->match(skb, 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;
++ destiny->target(skb, in, out, hooknum, destiny, NULL);
++ return;
++}
++
++static unsigned int chaos_tg(struct sk_buff *skb,
++ const struct net_device *in, const struct net_device *out,
++ unsigned int hooknum, const struct xt_target *target, const void *targinfo)
++{
++ /*
++ * Equivalent to:
++ * -A chaos -m statistic --mode random --probability \
++ * $reject_percentage -j REJECT --reject-with host-unreach;
++ * -A chaos -p tcp -m statistic --mode random --probability \
++ * $delude_percentage -j DELUDE;
++ * -A chaos -j DROP;
++ */
++ const struct xt_chaos_target_info *info = targinfo;
++ const struct iphdr *iph = ip_hdr(skb);
++
++ if ((unsigned int)net_random() <= reject_percentage)
++ return xt_reject->target(skb, in, out, hooknum, target,
++ &reject_params);
++
++ /* TARPIT/DELUDE may not be called from the OUTPUT chain */
++ if (iph->protocol == IPPROTO_TCP &&
++ info->variant != XTCHAOS_NORMAL && hooknum != NF_IP_LOCAL_OUT)
++ xt_chaos_total(info, skb, in, out, hooknum);
++
++ return NF_DROP;
++}
++
++static bool chaos_tg_check(const char *tablename, const void *entry,
++ const struct xt_target *target, void *targinfo, unsigned int hook_mask)
++{
++ const struct xt_chaos_target_info *info = targinfo;
++
++ if (info->variant == XTCHAOS_DELUDE && !have_delude) {
++ printk(KERN_WARNING PFX "Error: Cannot use --delude when "
++ "DELUDE module not available\n");
++ return false;
++ }
++ if (info->variant == XTCHAOS_TARPIT && !have_tarpit) {
++ printk(KERN_WARNING PFX "Error: Cannot use --tarpit when "
++ "TARPIT module not available\n");
++ return false;
++ }
++
++ return true;
++}
++
++static struct xt_target chaos_tg_reg = {
++ .name = "CHAOS",
++ .family = AF_INET,
++ .table = "filter",
++ .hooks = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) |
++ (1 << NF_IP_LOCAL_OUT),
++ .checkentry = chaos_tg_check,
++ .target = chaos_tg,
++ .targetsize = sizeof(struct xt_chaos_target_info),
++ .me = THIS_MODULE,
++};
++
++static int __init chaos_tg_init(void)
++{
++ int ret = -EINVAL;
++
++ xm_tcp = xt_request_find_match(AF_INET, "tcp", 0);
++ if (xm_tcp == NULL) {
++ printk(KERN_WARNING PFX "Error: Could not find or load "
++ "\"tcp\" match\n");
++ return -EINVAL;
++ }
++
++ xt_reject = xt_request_find_target(AF_INET, "REJECT", 0);
++ if (xt_reject == NULL) {
++ printk(KERN_WARNING PFX "Error: Could not find or load "
++ "\"REJECT\" target\n");
++ goto out2;
++ }
++
++ xt_tarpit = xt_request_find_target(AF_INET, "TARPIT", 0);
++ have_tarpit = xt_tarpit != NULL;
++ if (!have_tarpit)
++ printk(KERN_WARNING PFX "Warning: Could not find or load "
++ "\"TARPIT\" target\n");
++
++ xt_delude = xt_request_find_target(AF_INET, "DELUDE", 0);
++ have_delude = xt_delude != NULL;
++ if (!have_delude)
++ printk(KERN_WARNING PFX "Warning: Could not find or load "
++ "\"DELUDE\" target\n");
++
++ if ((ret = xt_register_target(&chaos_tg_reg)) != 0) {
++ printk(KERN_WARNING PFX "xt_register_target returned "
++ "error %d\n", ret);
++ goto out3;
++ }
++
++ return 0;
++
++ out3:
++ if (have_delude)
++ module_put(xt_delude->me);
++ if (have_tarpit)
++ module_put(xt_tarpit->me);
++ module_put(xt_reject->me);
++ out2:
++ module_put(xm_tcp->me);
++ return ret;
++}
++
++static void __exit chaos_tg_exit(void)
++{
++ xt_unregister_target(&chaos_tg_reg);
++ module_put(xm_tcp->me);
++ module_put(xt_reject->me);
++ if (have_delude)
++ module_put(xt_delude->me);
++ if (have_tarpit)
++ module_put(xt_tarpit->me);
++ return;
++}
++
++module_init(chaos_tg_init);
++module_exit(chaos_tg_exit);
++MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
++MODULE_DESCRIPTION("netfilter \"CHAOS\" target");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_CHAOS");
+Index: linux-2.6.24/net/netfilter/xt_DELUDE.c
+===================================================================
+--- /dev/null
++++ linux-2.6.24/net/netfilter/xt_DELUDE.c
+@@ -0,0 +1,197 @@
++/*
++ * DELUDE target
++ * Copyright © CC Computer Consultants GmbH, 2007
++ * Contact: Jan Engelhardt <jengelh@computergmbh.de>
++ *
++ * 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>
++ *
++ * xt_DELUDE acts like REJECT, but does reply with SYN-ACK on SYN.
++ *
++ * 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/netfilter/x_tables.h>
++#ifdef CONFIG_BRIDGE_NETFILTER
++# include <linux/netfilter_bridge.h>
++#endif
++#include <net/tcp.h>
++#define PFX KBUILD_MODNAME ": "
++
++static void delude_send_reset(struct sk_buff *oldskb, unsigned int hook)
++{
++ struct tcphdr _otcph, *oth, *tcph;
++ unsigned int addr_type;
++ struct sk_buff *nskb;
++ u_int16_t tmp_port;
++ u_int32_t tmp_addr;
++ struct iphdr *niph;
++ bool needs_ack;
++
++ /* IP header checks: fragment. */
++ if (ip_hdr(oldskb)->frag_off & htons(IP_OFFSET))
++ return;
++
++ oth = skb_header_pointer(oldskb, ip_hdrlen(oldskb),
++ sizeof(_otcph), &_otcph);
++ if (oth == NULL)
++ return;
++
++ /* No RST for RST. */
++ if (oth->rst)
++ return;
++
++ /* Check checksum */
++ if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), IPPROTO_TCP))
++ return;
++
++ /* 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, LL_MAX_HEADER, skb_tailroom(oldskb),
++ GFP_ATOMIC);
++ if (!nskb)
++ return;
++
++ /* This packet will not be the same as the other: clear nf fields */
++ nf_reset(nskb);
++ nskb->mark = 0;
++ skb_init_secmark(nskb);
++
++ skb_shinfo(nskb)->gso_size = 0;
++ skb_shinfo(nskb)->gso_segs = 0;
++ skb_shinfo(nskb)->gso_type = 0;
++
++ tcph = (struct tcphdr *)(skb_network_header(nskb) + ip_hdrlen(nskb));
++
++ /* Swap source and dest */
++ niph = ip_hdr(nskb);
++ tmp_addr = niph->saddr;
++ niph->saddr = niph->daddr;
++ niph->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, ip_hdrlen(nskb) + sizeof(struct tcphdr));
++ niph->tot_len = htons(nskb->len);
++
++ if (oth->syn && !oth->ack && !oth->rst && !oth->fin) {
++ /* DELUDE essential part */
++ tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin +
++ oldskb->len - ip_hdrlen(oldskb) -
++ (oth->doff << 2));
++ tcph->seq = false;
++ tcph->ack = true;
++ } else {
++ if (!tcph->ack) {
++ needs_ack = true;
++ tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn +
++ oth->fin + oldskb->len -
++ ip_hdrlen(oldskb) - (oth->doff<<2));
++ tcph->seq = false;
++ } else {
++ needs_ack = false;
++ tcph->seq = oth->ack_seq;
++ tcph->ack_seq = false;
++ }
++
++ /* Reset flags */
++ ((u_int8_t *)tcph)[13] = 0;
++ tcph->rst = true;
++ tcph->ack = needs_ack;
++ }
++
++ tcph->window = 0;
++ tcph->urg_ptr = 0;
++
++ /* Adjust TCP checksum */
++ tcph->check = 0;
++ tcph->check = tcp_v4_check(sizeof(struct tcphdr), niph->saddr,
++ niph->daddr, csum_partial((char *)tcph,
++ sizeof(struct tcphdr), 0));
++
++ /* Set DF, id = 0 */
++ niph->frag_off = htons(IP_DF);
++ niph->id = 0;
++
++ addr_type = RTN_UNSPEC;
++#ifdef CONFIG_BRIDGE_NETFILTER
++ if (hook != NF_IP_FORWARD || (nskb->nf_bridge != NULL &&
++ nskb->nf_bridge->mask & BRNF_BRIDGED))
++#else
++ if (hook != NF_IP_FORWARD)
++#endif
++ addr_type = RTN_LOCAL;
++
++ if (ip_route_me_harder(nskb, addr_type))
++ goto free_nskb;
++
++ nskb->ip_summed = CHECKSUM_NONE;
++
++ /* Adjust IP TTL */
++ niph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
++
++ /* Adjust IP checksum */
++ niph->check = 0;
++ niph->check = ip_fast_csum(skb_network_header(nskb), niph->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);
++}
++
++static unsigned int delude_tg(struct sk_buff *skb,
++ const struct net_device *in, const struct net_device *out,
++ unsigned int hooknum, const struct xt_target *target, const void *targinfo)
++{
++ /* WARNING: This code causes reentry within iptables.
++ This means that the iptables jump stack is now crap. We
++ must return an absolute verdict. --RR */
++ delude_send_reset(skb, hooknum);
++ return NF_DROP;
++}
++
++static struct xt_target delude_tg_reg = {
++ .name = "DELUDE",
++ .family = AF_INET,
++ .table = "filter",
++ .hooks = (1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD),
++ .target = delude_tg,
++ .proto = IPPROTO_TCP,
++ .me = THIS_MODULE,
++};
++
++static int __init delude_tg_init(void)
++{
++ return xt_register_target(&delude_tg_reg);
++}
++
++static void __exit delude_tg_exit(void)
++{
++ xt_unregister_target(&delude_tg_reg);
++}
++
++module_init(delude_tg_init);
++module_exit(delude_tg_exit);
++MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
++MODULE_DESCRIPTION("netfilter \"DELUDE\" target");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_DELUDE");
+Index: linux-2.6.24/net/netfilter/xt_portscan.c
+===================================================================
+--- /dev/null
++++ linux-2.6.24/net/netfilter/xt_portscan.c
+@@ -0,0 +1,269 @@
++/*
++ * portscan match for netfilter
++ * Copyright © CC Computer Consultants GmbH, 2006 - 2007
++ * Contact: Jan Engelhardt <jengelh@computergmbh.de>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License; either version
++ * 2 or 3 as published by the Free Software Foundation.
++ */
++#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>
++#include <net/netfilter/nf_nat_rule.h>
++#if defined(_LOCAL)
++# include "xt_portscan.h"
++#elif defined(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) || \
++ defined(CONFIG_NETFILTER_XT_MATCH_PORTSCAN_MODULE)
++# include <linux/netfilter/xt_portscan.h>
++#else
++# include "xt_portscan.h"
++#endif
++#define PFX KBUILD_MODNAME ": "
++
++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 bool tflg_ack4(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_ACK;
++}
++
++static inline bool tflg_ack6(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL6) == TCP_FLAG_ACK;
++}
++
++static inline bool tflg_fin(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_FIN;
++}
++
++static inline bool tflg_rst(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_RST;
++}
++
++static inline bool tflg_rstack(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
++ (TCP_FLAG_ACK | TCP_FLAG_RST);
++}
++
++static inline bool tflg_syn(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_SYN;
++}
++
++static inline bool tflg_synack(const struct tcphdr *th)
++{
++ return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
++ (TCP_FLAG_SYN | TCP_FLAG_ACK);
++}
++
++/* portscan functions */
++static inline bool portscan_mt_stealth(const struct tcphdr *th)
++{
++ /*
++ * "Connection refused" replies to our own probes must not be matched.
++ */
++ if (tflg_rstack(th))
++ return false;
++
++ if (tflg_rst(th) && printk_ratelimit()) {
++ printk(KERN_WARNING PFX "Warning: Pure RST received\n");
++ return false;
++ }
++
++ /*
++ * -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 unsigned int portscan_mt_full(int mark,
++ enum ip_conntrack_info ctstate, bool loopback, const struct tcphdr *tcph,
++ unsigned 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 bool portscan_mt(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, bool *hotdrop)
++{
++ const struct xt_portscan_match_info *info = matchinfo;
++ enum ip_conntrack_info ctstate;
++ const struct tcphdr *tcph;
++ struct nf_conn *ctdata;
++ struct tcphdr tcph_buf;
++
++ tcph = skb_header_pointer(skb, protoff, sizeof(tcph_buf), &tcph_buf);
++ if (tcph == NULL)
++ return false;
++
++ /* Check for invalid packets: -m conntrack --ctstate INVALID */
++ if ((ctdata = nf_ct_get(skb, &ctstate)) == NULL) {
++ if (info->match_stealth)
++ return portscan_mt_stealth(tcph);
++ /*
++ * If @ctdata is NULL, we cannot match the other scan
++ * types, return.
++ */
++ return false;
++ }
++
++ /*
++ * 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->mark & packet_mask) != mark_seen) {
++ unsigned int n;
++
++ n = portscan_mt_full(ctdata->mark & connmark_mask, ctstate,
++ (in->flags & IFF_LOOPBACK) == IFF_LOOPBACK, tcph,
++ skb->len - protoff - 4 * tcph->doff);
++
++ ctdata->mark = (ctdata->mark & ~connmark_mask) | n;
++ ((struct sk_buff *)skb)->mark =
++ (skb->mark & ~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 bool portscan_mt_check(const char *tablename, const void *entry,
++ const struct xt_match *match, void *matchinfo, unsigned int hook_mask)
++{
++ const struct xt_portscan_match_info *info = matchinfo;
++
++ 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 false;
++ }
++ return true;
++}
++
++static struct xt_match portscan_mt_reg __read_mostly = {
++ .name = "portscan",
++ .family = AF_INET,
++ .match = portscan_mt,
++ .checkentry = portscan_mt_check,
++ .matchsize = sizeof(struct xt_portscan_match_info),
++ .proto = IPPROTO_TCP,
++ .me = THIS_MODULE,
++};
++
++static int __init portscan_mt_init(void)
++{
++ return xt_register_match(&portscan_mt_reg);
++}
++
++static void __exit portscan_mt_exit(void)
++{
++ xt_unregister_match(&portscan_mt_reg);
++ return;
++}
++
++module_init(portscan_mt_init);
++module_exit(portscan_mt_exit);
++MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
++MODULE_DESCRIPTION("netfilter \"portscan\" match");
++MODULE_LICENSE("GPL");
++MODULE_ALIAS("ipt_portscan");
+Index: linux-2.6.24/drivers/char/random.c
+===================================================================
+--- linux-2.6.24.orig/drivers/char/random.c
++++ linux-2.6.24/drivers/char/random.c
+@@ -1564,6 +1564,8 @@ __u32 secure_tcp_sequence_number(__be32
+ return seq;
+ }
+
++EXPORT_SYMBOL(secure_tcp_sequence_number);
++
+ /* Generate secure starting point for ephemeral IPV4 transport port search */
+ u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
+ {
projects / openwrt / svn-archive / archive.git / blobdiff