2007-05-26 22:41:42 +03:00
|
|
|
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
|
|
|
|
--- linux-2.6.21.1.old/include/linux/netfilter/oot_conntrack.h 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/include/linux/netfilter/oot_conntrack.h 2007-05-26 20:40:10.922195992 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,5 @@
|
|
|
|
+#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
|
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|
|
+# include <linux/netfilter_ipv4/ip_conntrack.h>
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|
|
|
+#else /* linux-2.6.20+ */
|
|
|
|
+# include <net/netfilter/nf_nat_rule.h>
|
|
|
|
+#endif
|
2007-05-26 22:41:42 +03:00
|
|
|
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
|
|
|
|
--- linux-2.6.21.1.old/include/linux/netfilter/oot_trans.h 1970-01-01 01:00:00.000000000 +0100
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|
|
|
+++ linux-2.6.21.1.dev/include/linux/netfilter/oot_trans.h 2007-05-26 20:40:10.940193256 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,14 @@
|
|
|
|
+/* Out of tree workarounds */
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|
|
|
+#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)
|
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|
|
+# define nfmark mark
|
|
|
|
+#endif
|
|
|
|
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 21)
|
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|
|
+# define tcp_v4_check(tcph, tcph_sz, s, d, csp) \
|
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|
|
+ tcp_v4_check((tcph_sz), (s), (d), (csp))
|
|
|
|
+#endif
|
2007-05-26 22:41:42 +03:00
|
|
|
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
|
|
|
|
--- linux-2.6.21.1.old/include/linux/netfilter/xt_CHAOS.h 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/include/linux/netfilter/xt_CHAOS.h 2007-05-26 20:40:10.940193256 +0200
|
2007-01-23 01:55:22 +02:00
|
|
|
@@ -0,0 +1,14 @@
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|
|
+#ifndef _LINUX_XT_CHAOS_H
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|
|
+#define _LINUX_XT_CHAOS_H 1
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|
+
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|
|
+enum xt_chaos_variant {
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|
|
+ XTCHAOS_NORMAL,
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|
|
+ XTCHAOS_TARPIT,
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|
|
+ XTCHAOS_DELUDE,
|
|
|
|
+};
|
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|
|
+
|
|
|
|
+struct xt_chaos_info {
|
|
|
|
+ enum xt_chaos_variant variant;
|
|
|
|
+};
|
|
|
|
+
|
|
|
|
+#endif /* _LINUX_XT_CHAOS_H */
|
2007-05-26 22:41:42 +03:00
|
|
|
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
|
|
|
|
--- linux-2.6.21.1.old/include/linux/netfilter/xt_portscan.h 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/include/linux/netfilter/xt_portscan.h 2007-05-26 20:40:10.940193256 +0200
|
2007-01-23 01:55:22 +02:00
|
|
|
@@ -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 */
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/find_match.c linux-2.6.21.1.dev/net/netfilter/find_match.c
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/find_match.c 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/find_match.c 2007-05-26 20:40:10.970188696 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,39 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
+/*
|
|
|
|
+ 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
|
|
|
|
+ */
|
2007-05-23 22:48:34 +03:00
|
|
|
+static struct xt_match *xt_request_find_match_lo(int af, const char *name,
|
2007-01-23 01:55:22 +02:00
|
|
|
+ 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;
|
|
|
|
+}
|
2007-05-23 22:48:34 +03:00
|
|
|
+
|
|
|
|
+/* In case it goes into mainline, let this out-of-tree package compile */
|
|
|
|
+#define xt_request_find_match xt_request_find_match_lo
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/Kconfig linux-2.6.21.1.dev/net/netfilter/Kconfig
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/Kconfig 2007-04-27 23:49:26.000000000 +0200
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/Kconfig 2007-05-26 20:40:11.003183680 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -287,6 +287,14 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
|
|
|
|
# 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
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -315,6 +323,14 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
<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
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -563,6 +579,14 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
|
|
|
|
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
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/Makefile linux-2.6.21.1.dev/net/netfilter/Makefile
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/Makefile 2007-04-27 23:49:26.000000000 +0200
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/Makefile 2007-05-26 20:40:11.003183680 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -37,8 +37,10 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
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
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -63,6 +65,7 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
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
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/xt_CHAOS.c linux-2.6.21.1.dev/net/netfilter/xt_CHAOS.c
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/xt_CHAOS.c 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/xt_CHAOS.c 2007-05-26 20:40:11.004183528 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,204 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
+/*
|
2007-05-23 22:48:34 +03:00
|
|
|
+ CHAOS target for netfilter
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
|
|
|
|
+ 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.
|
2007-01-23 01:55:22 +02:00
|
|
|
+*/
|
|
|
|
+#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"
|
2007-05-23 22:48:34 +03:00
|
|
|
+#include <linux/netfilter/oot_trans.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#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;
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+static int have_delude, have_tarpit;
|
|
|
|
+
|
2007-01-23 01:55:22 +02:00
|
|
|
+/* 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;
|
2007-05-23 22:48:34 +03:00
|
|
|
+ * -A chaos -p tcp -m statistic --mode random --probability \
|
2007-01-23 01:55:22 +02:00
|
|
|
+ * $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;
|
|
|
|
+}
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+static int xt_chaos_checkentry(const char *tablename, const void *entry,
|
|
|
|
+ const struct xt_target *target, void *targinfo,
|
|
|
|
+#ifdef HAVE_TARGINFOSIZE
|
|
|
|
+ unsigned int targinfosize,
|
|
|
|
+#endif
|
|
|
|
+ unsigned int hook_mask)
|
|
|
|
+{
|
|
|
|
+ const struct xt_chaos_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 0;
|
|
|
|
+ }
|
|
|
|
+ if(info->variant == XTCHAOS_TARPIT && !have_tarpit) {
|
|
|
|
+ printk(KERN_WARNING PFX "Error: Cannot use --tarpit when "
|
|
|
|
+ "TARPIT module not available\n");
|
|
|
|
+ return 0;
|
|
|
|
+ }
|
|
|
|
+ return 1;
|
|
|
|
+}
|
|
|
|
+
|
2007-01-23 01:55:22 +02:00
|
|
|
+static struct xt_target xt_chaos_info = {
|
|
|
|
+ .name = "CHAOS",
|
|
|
|
+ .target = xt_chaos_target,
|
2007-05-23 22:48:34 +03:00
|
|
|
+ .checkentry = xt_chaos_checkentry,
|
2007-01-23 01:55:22 +02:00
|
|
|
+ .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) {
|
2007-05-23 22:48:34 +03:00
|
|
|
+ printk(KERN_WARNING PFX "Error: Could not find or load "
|
|
|
|
+ "\"tcp\" match\n");
|
2007-01-23 01:55:22 +02:00
|
|
|
+ return -EINVAL;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ xt_reject = xt_request_find_target(AF_INET, "REJECT", 0);
|
|
|
|
+ if(xt_reject == NULL) {
|
2007-05-23 22:48:34 +03:00
|
|
|
+ printk(KERN_WARNING PFX "Error: Could not find or load "
|
|
|
|
+ "\"REJECT\" target\n");
|
2007-01-23 01:55:22 +02:00
|
|
|
+ goto out2;
|
|
|
|
+ }
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ 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");
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ 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");
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
|
|
|
+ if((ret = xt_register_target(&xt_chaos_info)) != 0) {
|
|
|
|
+ printk(KERN_WARNING PFX "xt_register_target returned "
|
|
|
|
+ "error %d\n", ret);
|
2007-05-23 22:48:34 +03:00
|
|
|
+ goto out3;
|
2007-01-23 01:55:22 +02:00
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ return 0;
|
|
|
|
+
|
|
|
|
+ out3:
|
2007-05-23 22:48:34 +03:00
|
|
|
+ if(have_delude)
|
|
|
|
+ module_put(xt_delude->me);
|
|
|
|
+ if(have_tarpit)
|
|
|
|
+ module_put(xt_tarpit->me);
|
2007-01-23 01:55:22 +02:00
|
|
|
+ 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);
|
2007-05-23 22:48:34 +03:00
|
|
|
+ if(have_delude)
|
|
|
|
+ module_put(xt_delude->me);
|
|
|
|
+ if(have_tarpit)
|
|
|
|
+ module_put(xt_tarpit->me);
|
2007-01-23 01:55:22 +02:00
|
|
|
+ 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");
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/xt_DELUDE.c linux-2.6.21.1.dev/net/netfilter/xt_DELUDE.c
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/xt_DELUDE.c 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/xt_DELUDE.c 2007-05-26 20:40:11.004183528 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,288 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
+/*
|
2007-05-23 22:48:34 +03:00
|
|
|
+ DELUDE target
|
|
|
|
+ Copyright © Jan Engelhardt <jengelh [at] gmx de>, 2007
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ 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>
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ xt_DELUDE acts like REJECT, but does reply with SYN-ACK on SYN.
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ 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.
|
|
|
|
+*/
|
2007-01-23 01:55:22 +02:00
|
|
|
+#include <linux/module.h>
|
|
|
|
+#include <linux/skbuff.h>
|
|
|
|
+#include <linux/ip.h>
|
2007-05-23 22:48:34 +03:00
|
|
|
+#include <linux/random.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#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
|
2007-05-23 22:48:34 +03:00
|
|
|
+# include <linux/netfilter_bridge.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#endif
|
2007-05-23 22:48:34 +03:00
|
|
|
+#include <linux/netfilter/oot_trans.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#define PFX KBUILD_MODNAME ": "
|
|
|
|
+
|
|
|
|
+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;
|
2007-05-23 22:48:34 +03:00
|
|
|
+ __be16 tmp_port;
|
|
|
|
+ __be32 tmp_addr;
|
|
|
|
+ int needs_ack;
|
|
|
|
+ unsigned int addr_type;
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
|
|
|
+ /* 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)
|
2007-05-23 22:48:34 +03:00
|
|
|
+ return;
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ /* No RST for RST. */
|
|
|
|
+ if (oth->rst)
|
2007-01-23 01:55:22 +02:00
|
|
|
+ return;
|
|
|
|
+
|
|
|
|
+ /* Check checksum */
|
|
|
|
+ if (nf_ip_checksum(oldskb, hook, iph->ihl * 4, 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 */
|
2007-05-23 22:48:34 +03:00
|
|
|
+ nskb = skb_copy_expand(oldskb, LL_MAX_HEADER, skb_tailroom(oldskb),
|
2007-01-23 01:55:22 +02:00
|
|
|
+ GFP_ATOMIC);
|
2007-05-23 22:48:34 +03:00
|
|
|
+ if (!nskb)
|
2007-01-23 01:55:22 +02:00
|
|
|
+ return;
|
|
|
|
+
|
|
|
|
+ /* This packet will not be the same as the other: clear nf fields */
|
|
|
|
+ nf_reset(nskb);
|
|
|
|
+ nskb->nfmark = 0;
|
|
|
|
+ skb_init_secmark(nskb);
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ skb_shinfo(nskb)->gso_size = 0;
|
|
|
|
+ skb_shinfo(nskb)->gso_segs = 0;
|
|
|
|
+ skb_shinfo(nskb)->gso_type = 0;
|
|
|
|
+
|
2007-01-23 01:55:22 +02:00
|
|
|
+ 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);
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ 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 - oldskb->nh.iph->ihl * 4 -
|
|
|
|
+ (oth->doff << 2));
|
|
|
|
+ tcph->seq = htonl(secure_tcp_sequence_number(
|
|
|
|
+ nskb->nh.iph->saddr, nskb->nh.iph->daddr,
|
|
|
|
+ tcph->source, tcph->dest));
|
|
|
|
+ tcph->ack = 1;
|
|
|
|
+ } else {
|
|
|
|
+ if(!tcph->ack) {
|
|
|
|
+ needs_ack = 1;
|
|
|
|
+ tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin
|
|
|
|
+ + oldskb->len - oldskb->nh.iph->ihl*4
|
|
|
|
+ - (oth->doff<<2));
|
|
|
|
+ tcph->seq = 0;
|
|
|
|
+ } else {
|
|
|
|
+ needs_ack = 0;
|
|
|
|
+ tcph->seq = oth->ack_seq;
|
|
|
|
+ tcph->ack_seq = 0;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /* Reset flags */
|
|
|
|
+ ((u_int8_t *)tcph)[13] = 0;
|
|
|
|
+ tcph->rst = 1;
|
|
|
|
+ tcph->ack = needs_ack;
|
|
|
|
+ }
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
|
|
|
+
|
|
|
|
+ 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));
|
|
|
|
+
|
|
|
|
+ /* Set DF, id = 0 */
|
|
|
|
+ nskb->nh.iph->frag_off = htons(IP_DF);
|
|
|
|
+ nskb->nh.iph->id = 0;
|
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ addr_type = RTN_UNSPEC;
|
|
|
|
+ if (hook != NF_IP_FORWARD
|
|
|
|
+#ifdef CONFIG_BRIDGE_NETFILTER
|
|
|
|
+ || (nskb->nf_bridge && nskb->nf_bridge->mask & BRNF_BRIDGED)
|
|
|
|
+#endif
|
|
|
|
+ )
|
|
|
|
+ addr_type = RTN_LOCAL;
|
|
|
|
+
|
|
|
|
+ if (ip_route_me_harder(&nskb, addr_type))
|
|
|
|
+ goto free_nskb;
|
|
|
|
+
|
|
|
|
+ nskb->ip_summed = CHECKSUM_NONE;
|
|
|
|
+
|
|
|
|
+ /* Adjust IP TTL */
|
|
|
|
+ nskb->nh.iph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
|
|
|
|
+
|
2007-01-23 01:55:22 +02:00
|
|
|
+ /* 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);
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+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_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
|
|
|
|
+MODULE_DESCRIPTION("netfilter DELUDE target");
|
2007-05-23 22:48:34 +03:00
|
|
|
+MODULE_LICENSE("GPL");
|
|
|
|
+MODULE_ALIAS("ipt_DELUDE");
|
2007-05-26 22:41:42 +03:00
|
|
|
diff -urN linux-2.6.21.1.old/net/netfilter/xt_portscan.c linux-2.6.21.1.dev/net/netfilter/xt_portscan.c
|
|
|
|
--- linux-2.6.21.1.old/net/netfilter/xt_portscan.c 1970-01-01 01:00:00.000000000 +0100
|
|
|
|
+++ linux-2.6.21.1.dev/net/netfilter/xt_portscan.c 2007-05-26 20:40:11.004183528 +0200
|
2007-05-23 22:48:34 +03:00
|
|
|
@@ -0,0 +1,272 @@
|
2007-01-23 01:55:22 +02:00
|
|
|
+/*
|
2007-05-23 22:48:34 +03:00
|
|
|
+ portscan match for netfilter
|
2007-01-23 01:55:22 +02:00
|
|
|
+
|
2007-05-23 22:48:34 +03:00
|
|
|
+ Written by Jan Engelhardt, 2006 - 2007
|
|
|
|
+ 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.
|
2007-01-23 01:55:22 +02:00
|
|
|
+*/
|
|
|
|
+#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>
|
2007-05-23 22:48:34 +03:00
|
|
|
+#include <linux/netfilter/oot_conntrack.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#include <linux/netfilter/xt_portscan.h>
|
2007-05-23 22:48:34 +03:00
|
|
|
+#include <linux/netfilter/oot_trans.h>
|
2007-01-23 01:55:22 +02:00
|
|
|
+#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 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");
|