iptables: remove CHAOS and TARPIT patches
SVN-Revision: 14447
This commit is contained in:
		@@ -20,7 +20,7 @@ endif
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ifeq ($(CONFIG_LINUX_2_6),y)
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  PKG_VERSION:=1.4.1.1
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  PKG_RELEASE:=1
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  PKG_RELEASE:=2
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  PKG_MD5SUM:=723fa88d8a0915e184f99e03e9bf06cb
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endif
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@@ -1,393 +0,0 @@
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Index: iptables-1.4.0/extensions/.CHAOS-testx
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/.CHAOS-testx
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@@ -0,0 +1,3 @@
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+#! /bin/sh
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+
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+[ -f "$KERNEL_DIR/include/linux/netfilter/xt_CHAOS.h" ] && echo "CHAOS"
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Index: iptables-1.4.0/extensions/libxt_CHAOS.c
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/libxt_CHAOS.c
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@@ -0,0 +1,114 @@
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+/*
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+ *	CHAOS target for iptables
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+ *	Copyright © CC Computer Consultants GmbH, 2006 - 2007
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+ *	Contact: Jan Engelhardt <jengelh@computergmbh.de>
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+ *
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+ *	This program is free software; you can redistribute it and/or modify
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+ *	it under the terms of the GNU General Public License; either version
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+ *	2 or 3 as published by the Free Software Foundation.
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+ */
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+#include <getopt.h>
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+#include <stdbool.h>
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+#include <stdio.h>
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+#include <string.h>
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+
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+#include <xtables.h>
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+#include <linux/netfilter/x_tables.h>
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+#include <linux/netfilter/xt_CHAOS.h>
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+
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+enum {
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+	F_DELUDE = 1 << 0,
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+	F_TARPIT = 1 << 1,
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+};
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+
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+static const struct option chaos_tg_opts[] = {
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+	{.name = "delude", .has_arg = false, .val = 'd'},
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+	{.name = "tarpit", .has_arg = false, .val = 't'},
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+	{},
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+};
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+
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+static void chaos_tg_help(void)
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+{
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+	printf(
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+		"CHAOS target v%s options:\n"
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+		"  --delude     Enable DELUDE processing for TCP\n"
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+		"  --tarpit     Enable TARPIT processing for TCP\n",
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+		XTABLES_VERSION);
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+	return;
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+}
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+
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+static int chaos_tg_parse(int c, char **argv, int invert, unsigned int *flags,
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+    const void *entry, struct xt_entry_target **target)
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+{
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+	struct xt_chaos_target_info *info = (void *)((*target)->data);
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+	switch (c) {
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+		case 'd':
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+			info->variant = XTCHAOS_DELUDE;
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+			*flags |= F_DELUDE;
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+			return true;
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+		case 't':
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+			info->variant = XTCHAOS_TARPIT;
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+			*flags |= F_TARPIT;
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+			return true;
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+	}
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+	return false;
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+}
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+
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+static void chaos_tg_check(unsigned int flags)
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+{
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+	if ((flags & (F_DELUDE | F_TARPIT)) == (F_DELUDE | F_TARPIT))
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+		/* If flags == 0x03, both were specified, which should not be. */
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+		exit_error(PARAMETER_PROBLEM,
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+		           "CHAOS: only one of --tarpit or --delude "
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+		           "may be specified");
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+	return;
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+}
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+
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+static void chaos_tg_print(const void *ip,
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+    const struct xt_entry_target *target, int numeric)
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+{
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+	const struct xt_chaos_target_info *info = (const void *)target->data;
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+	switch (info->variant) {
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+		case XTCHAOS_DELUDE:
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+			printf("DELUDE ");
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+			break;
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+		case XTCHAOS_TARPIT:
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+			printf("TARPIT ");
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+			break;
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+	}
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+	return;
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+}
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+
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+static void chaos_tg_save(const void *ip, const struct xt_entry_target *target)
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+{
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+	const struct xt_chaos_target_info *info = (const void *)target->data;
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+	switch (info->variant) {
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+		case XTCHAOS_DELUDE:
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+			printf("--delude ");
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+			break;
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+		case XTCHAOS_TARPIT:
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+			printf("--tarpit ");
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+			break;
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+	}
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+	return;
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+}
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+
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+static struct xtables_target chaos_tg_reg = {
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+	.version       = XTABLES_VERSION,
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+	.name          = "CHAOS",
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+	.family        = AF_INET,
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+	.size          = XT_ALIGN(sizeof(struct xt_chaos_target_info)),
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+	.userspacesize = XT_ALIGN(sizeof(struct xt_chaos_target_info)),
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+	.help          = chaos_tg_help,
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+	.parse         = chaos_tg_parse,
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+	.final_check   = chaos_tg_check,
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+	.print         = chaos_tg_print,
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+	.save          = chaos_tg_save,
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+	.extra_opts    = chaos_tg_opts,
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+};
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+
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+void _init(void)
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+{
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+	xtables_register_target(&chaos_tg_reg);
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+	return;
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+}
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Index: iptables-1.4.0/extensions/libxt_CHAOS.man
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/libxt_CHAOS.man
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@@ -0,0 +1,18 @@
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+Causes confusion on the other end by doing odd things with incoming packets.
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+CHAOS will randomly reply (or not) with one of its configurable subtargets:
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+.TP
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+\fB--delude\fR
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+Use the REJECT and DELUDE targets as a base to do a sudden or deferred
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+connection reset, fooling some network scanners to return non-deterministic
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+(randomly open/closed) results, and in case it is deemed open, it is actually
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+closed/filtered.
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+.TP
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+\fB--tarpit\fR
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+Use the REJECT and TARPIT target as a base to hold the connection until it
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+times out. This consumes conntrack entries when connection tracking is loaded
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+(which usually is on most machines), and routers inbetween you and the Internet
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+may fail to do their connection tracking if they have to handle more
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+connections than they can.
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+.PP
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+The randomness factor of not replying vs. replying can be set during load-time
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+of the xt_CHAOS module or during runtime in /sys/modules/xt_CHAOS/parameters.
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Index: iptables-1.4.0/extensions/.DELUDE-testx
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/.DELUDE-testx
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@@ -0,0 +1,3 @@
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+#! /bin/sh
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+
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+[ -f "$KERNEL_DIR/net/netfilter/xt_DELUDE.c" ] && echo "DELUDE"
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Index: iptables-1.4.0/extensions/libxt_DELUDE.c
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/libxt_DELUDE.c
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@@ -0,0 +1,49 @@
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+/*
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+ *	DELUDE target for iptables
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+ *	Copyright © CC Computer Consultants GmbH, 2006 - 2007
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+ *	Contact: Jan Engelhardt <jengelh@computergmbh.de>
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+ *
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+ *	This program is free software; you can redistribute it and/or modify
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+ *	it under the terms of the GNU General Public License; either version
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+ *	2 or 3 as published by the Free Software Foundation.
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+ */
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+#include <getopt.h>
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+#include <stdio.h>
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+#include <string.h>
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+
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+#include <xtables.h>
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+#include <linux/netfilter/x_tables.h>
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+
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+static void delude_tg_help(void)
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+{
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+	printf("DELUDE takes no options\n");
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+	return;
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+}
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+
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+static int delude_tg_parse(int c, char **argv, int invert, unsigned int *flags,
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+    const void *entry, struct xt_entry_target **target)
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+{
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+	return 0;
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+}
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+
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+static void delude_tg_check(unsigned int flags)
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+{
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+	return;
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+}
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+
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+static struct xtables_target delude_tg_reg = {
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+	.version       = XTABLES_VERSION,
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+	.name          = "DELUDE",
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+	.family        = AF_INET,
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+	.size          = XT_ALIGN(0),
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+	.userspacesize = XT_ALIGN(0),
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+	.help          = delude_tg_help,
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+	.parse         = delude_tg_parse,
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+	.final_check   = delude_tg_check,
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+};
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+
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+void _init(void)
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+{
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+	xtables_register_target(&delude_tg_reg);
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+	return;
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+}
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Index: iptables-1.4.0/extensions/libxt_DELUDE.man
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/libxt_DELUDE.man
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@@ -0,0 +1,4 @@
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+The DELUDE target will reply to a SYN packet with SYN-ACK, and to all other
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+packets with an RST. This will terminate the connection much like REJECT, but
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+network scanners doing TCP half-open discovery can be spoofed to make them
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+belive the port is open rather than closed/filtered.
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Index: iptables-1.4.0/extensions/.portscan-testx
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/.portscan-testx
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@@ -0,0 +1,3 @@
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+#! /bin/sh
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+
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+[ -f "$KERNEL_DIR/include/linux/netfilter/xt_portscan.h" ] && echo "portscan"
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Index: iptables-1.4.0/extensions/libxt_portscan.c
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===================================================================
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--- /dev/null
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+++ iptables-1.4.0/extensions/libxt_portscan.c
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@@ -0,0 +1,127 @@
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+/*
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+ *	portscan match for iptables
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+ *	Copyright © CC Computer Consultants GmbH, 2006 - 2007
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+ *	Contact: Jan Engelhardt <jengelh@computergmbh.de>
 | 
			
		||||
+ *
 | 
			
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+ *	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 <stdbool.h>
 | 
			
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+#include <stdio.h>
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+#include <string.h>
 | 
			
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+#include <stdlib.h>
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+#include <getopt.h>
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+
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+#include <xtables.h>
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+#include <iptables.h>
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+#include <linux/netfilter/x_tables.h>
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+#include <linux/netfilter/xt_portscan.h>
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+
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+static const struct option portscan_mt_opts[] = {
 | 
			
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+	{.name = "stealth", .has_arg = false, .val = 'x'},
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+	{.name = "synscan", .has_arg = false, .val = 's'},
 | 
			
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+	{.name = "cnscan",  .has_arg = false, .val = 'c'},
 | 
			
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+	{.name = "grscan",  .has_arg = false, .val = 'g'},
 | 
			
		||||
+	{},
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		||||
+};
 | 
			
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+
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+static void portscan_mt_help(void)
 | 
			
		||||
+{
 | 
			
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+	printf(
 | 
			
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+		"portscan match v%s options:\n"
 | 
			
		||||
+		"(Combining them will make them match by OR-logic)\n"
 | 
			
		||||
+		"  --stealth    Match TCP Stealth packets\n"
 | 
			
		||||
+		"  --synscan    Match TCP SYN scans\n"
 | 
			
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+		"  --cnscan     Match TCP Connect scans\n"
 | 
			
		||||
+		"  --grscan     Match Banner Grabbing scans\n",
 | 
			
		||||
+		XTABLES_VERSION);
 | 
			
		||||
+	return;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static int portscan_mt_parse(int c, char **argv, int invert,
 | 
			
		||||
+    unsigned int *flags, const void *entry, struct xt_entry_match **match)
 | 
			
		||||
+{
 | 
			
		||||
+	struct xt_portscan_match_info *info = (void *)((*match)->data);
 | 
			
		||||
+
 | 
			
		||||
+	switch (c) {
 | 
			
		||||
+		case 'c':
 | 
			
		||||
+			info->match_cn = true;
 | 
			
		||||
+			return true;
 | 
			
		||||
+		case 'g':
 | 
			
		||||
+			info->match_gr = true;
 | 
			
		||||
+			return true;
 | 
			
		||||
+		case 's':
 | 
			
		||||
+			info->match_syn = true;
 | 
			
		||||
+			return true;
 | 
			
		||||
+		case 'x':
 | 
			
		||||
+			info->match_stealth = true;
 | 
			
		||||
+			return true;
 | 
			
		||||
+	}
 | 
			
		||||
+	return false;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void portscan_mt_check(unsigned int flags)
 | 
			
		||||
+{
 | 
			
		||||
+	return;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void portscan_mt_print(const void *ip,
 | 
			
		||||
+    const struct xt_entry_match *match, int numeric)
 | 
			
		||||
+{
 | 
			
		||||
+	const struct xt_portscan_match_info *info = (const void *)(match->data);
 | 
			
		||||
+	const char *s = "";
 | 
			
		||||
+
 | 
			
		||||
+	printf("portscan ");
 | 
			
		||||
+	if (info->match_stealth) {
 | 
			
		||||
+		printf("STEALTH");
 | 
			
		||||
+		s = ",";
 | 
			
		||||
+	}
 | 
			
		||||
+	if (info->match_syn) {
 | 
			
		||||
+		printf("%sSYNSCAN", s);
 | 
			
		||||
+		s = ",";
 | 
			
		||||
+	}
 | 
			
		||||
+	if (info->match_cn) {
 | 
			
		||||
+		printf("%sCNSCAN", s);
 | 
			
		||||
+		s = ",";
 | 
			
		||||
+	}
 | 
			
		||||
+	if (info->match_gr)
 | 
			
		||||
+		printf("%sGRSCAN", s);
 | 
			
		||||
+	printf(" ");
 | 
			
		||||
+	return;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void portscan_mt_save(const void *ip, const struct xt_entry_match *match)
 | 
			
		||||
+{
 | 
			
		||||
+	const struct xt_portscan_match_info *info = (const void *)(match->data);
 | 
			
		||||
+
 | 
			
		||||
+	if (info->match_stealth)
 | 
			
		||||
+		printf("--stealth ");
 | 
			
		||||
+	if (info->match_syn)
 | 
			
		||||
+		printf("--synscan ");
 | 
			
		||||
+	if (info->match_cn)
 | 
			
		||||
+		printf("--cnscan ");
 | 
			
		||||
+	if (info->match_gr)
 | 
			
		||||
+		printf("--grscan ");
 | 
			
		||||
+	return;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static struct xtables_match portscan_mt_reg = {
 | 
			
		||||
+	.version       = XTABLES_VERSION,
 | 
			
		||||
+	.name          = "portscan",
 | 
			
		||||
+	.family        = AF_INET,
 | 
			
		||||
+	.size          = XT_ALIGN(sizeof(struct xt_portscan_match_info)),
 | 
			
		||||
+	.userspacesize = XT_ALIGN(sizeof(struct xt_portscan_match_info)),
 | 
			
		||||
+	.help          = portscan_mt_help,
 | 
			
		||||
+	.parse         = portscan_mt_parse,
 | 
			
		||||
+	.final_check   = portscan_mt_check,
 | 
			
		||||
+	.print         = portscan_mt_print,
 | 
			
		||||
+	.save          = portscan_mt_save,
 | 
			
		||||
+	.extra_opts    = portscan_mt_opts,
 | 
			
		||||
+};
 | 
			
		||||
+
 | 
			
		||||
+void _init(void)
 | 
			
		||||
+{
 | 
			
		||||
+	xtables_register_match(&portscan_mt_reg);
 | 
			
		||||
+	return;
 | 
			
		||||
+}
 | 
			
		||||
Index: iptables-1.4.0/extensions/libxt_portscan.man
 | 
			
		||||
===================================================================
 | 
			
		||||
--- /dev/null
 | 
			
		||||
+++ iptables-1.4.0/extensions/libxt_portscan.man
 | 
			
		||||
@@ -0,0 +1,27 @@
 | 
			
		||||
+Detects simple port scan attemps based upon the packet's contents. (This is
 | 
			
		||||
+different from other implementations, which also try to match the rate of new
 | 
			
		||||
+connections.) Note that an attempt is only discovered after it has been carried
 | 
			
		||||
+out, but this information can be used in conjunction with other rules to block
 | 
			
		||||
+the remote host's future connections. So this match module will match on the
 | 
			
		||||
+(probably) last packet the remote side will send to your machine.
 | 
			
		||||
+.TP
 | 
			
		||||
+\fB--stealth\fR
 | 
			
		||||
+Match if the packet did not belong to any known TCP connection
 | 
			
		||||
+(Stealth/FIN/XMAS/NULL scan).
 | 
			
		||||
+.TP
 | 
			
		||||
+\fB--synscan\fR
 | 
			
		||||
+Match if the connection was a TCP half-open discovery (SYN scan), i.e. the
 | 
			
		||||
+connection was torn down after the 2nd packet in the 3-way handshake.
 | 
			
		||||
+.TP
 | 
			
		||||
+\fB--cnscan\fR
 | 
			
		||||
+Match if the connection was a TCP full open discovery (connect scan), i.e. the
 | 
			
		||||
+connection was torn down after completion of the 3-way handshake.
 | 
			
		||||
+.TP
 | 
			
		||||
+\fB--grscan\fR
 | 
			
		||||
+Match if data in the connection only flew in the direction of the remote side,
 | 
			
		||||
+e.g. if the connection was terminated after a locally running daemon sent its
 | 
			
		||||
+identification. (e.g. openssh)
 | 
			
		||||
+.PP
 | 
			
		||||
+NOTE: Some clients (Windows XP for example) may do what looks like a SYN scan,
 | 
			
		||||
+so be advised to carefully use xt_portscan in conjunction with blocking rules,
 | 
			
		||||
+as it may lock out your very own internal network.
 | 
			
		||||
@@ -1,106 +0,0 @@
 | 
			
		||||
Index: iptables-1.4.0/extensions/libxt_TARPIT.c
 | 
			
		||||
===================================================================
 | 
			
		||||
--- /dev/null
 | 
			
		||||
+++ iptables-1.4.0/extensions/libxt_TARPIT.c
 | 
			
		||||
@@ -0,0 +1,55 @@
 | 
			
		||||
+/* Shared library add-on to iptables to add TARPIT target support */
 | 
			
		||||
+#include <stdio.h>
 | 
			
		||||
+#include <getopt.h>
 | 
			
		||||
+
 | 
			
		||||
+#include <xtables.h>
 | 
			
		||||
+#include <linux/netfilter/x_tables.h>
 | 
			
		||||
+
 | 
			
		||||
+static void TARPIT_help(void)
 | 
			
		||||
+{
 | 
			
		||||
+	fputs(
 | 
			
		||||
+"TARPIT takes no options\n"
 | 
			
		||||
+"\n", stdout);
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static struct option TARPIT_opts[] = {
 | 
			
		||||
+	{ 0 }
 | 
			
		||||
+};
 | 
			
		||||
+
 | 
			
		||||
+static int TARPIT_parse(int c, char **argv, int invert, unsigned int *flags,
 | 
			
		||||
+			const void *entry, struct xt_entry_target **target)
 | 
			
		||||
+{
 | 
			
		||||
+	return 0;
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void TARPIT_final_check(unsigned int flags)
 | 
			
		||||
+{
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void TARPIT_print(const void *ip, const struct xt_entry_target *target,
 | 
			
		||||
+			int numeric)
 | 
			
		||||
+{
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static void TARPIT_save(const void *ip, const struct xt_entry_target *target)
 | 
			
		||||
+{
 | 
			
		||||
+}
 | 
			
		||||
+
 | 
			
		||||
+static struct xtables_target tarpit_target = {
 | 
			
		||||
+	.family		= AF_INET,
 | 
			
		||||
+	.name		= "TARPIT",
 | 
			
		||||
+	.version	= XTABLES_VERSION,
 | 
			
		||||
+	.size		= XT_ALIGN(0),
 | 
			
		||||
+	.userspacesize	= XT_ALIGN(0),
 | 
			
		||||
+	.help		= TARPIT_help,
 | 
			
		||||
+	.parse		= TARPIT_parse,
 | 
			
		||||
+	.final_check	= TARPIT_final_check,
 | 
			
		||||
+	.print		= TARPIT_print,
 | 
			
		||||
+	.save		= TARPIT_save,
 | 
			
		||||
+	.extra_opts	= TARPIT_opts
 | 
			
		||||
+};
 | 
			
		||||
+
 | 
			
		||||
+void _init(void)
 | 
			
		||||
+{
 | 
			
		||||
+	xtables_register_target(&tarpit_target);
 | 
			
		||||
+}
 | 
			
		||||
Index: iptables-1.4.0/extensions/libxt_TARPIT.man
 | 
			
		||||
===================================================================
 | 
			
		||||
--- /dev/null
 | 
			
		||||
+++ iptables-1.4.0/extensions/libxt_TARPIT.man
 | 
			
		||||
@@ -0,0 +1,34 @@
 | 
			
		||||
+Captures and holds incoming TCP connections using no local
 | 
			
		||||
+per-connection resources. Connections are accepted, but immediately
 | 
			
		||||
+switched to the persist state (0 byte window), in which the remote
 | 
			
		||||
+side stops sending data and asks to continue every 60-240 seconds.
 | 
			
		||||
+Attempts to close the connection are ignored, forcing the remote side
 | 
			
		||||
+to time out the connection in 12-24 minutes.
 | 
			
		||||
+
 | 
			
		||||
+This offers similar functionality to LaBrea
 | 
			
		||||
+<http://www.hackbusters.net/LaBrea/> but doesn't require dedicated
 | 
			
		||||
+hardware or IPs. Any TCP port that you would normally DROP or REJECT
 | 
			
		||||
+can instead become a tarpit.
 | 
			
		||||
+
 | 
			
		||||
+To tarpit connections to TCP port 80 destined for the current machine:
 | 
			
		||||
+.IP
 | 
			
		||||
+iptables -A INPUT -p tcp -m tcp --dport 80 -j TARPIT
 | 
			
		||||
+.P
 | 
			
		||||
+To significantly slow down Code Red/Nimda-style scans of unused address
 | 
			
		||||
+space, forward unused ip addresses to a Linux box not acting as a router
 | 
			
		||||
+(e.g. "ip route 10.0.0.0 255.0.0.0 ip.of.linux.box" on a Cisco), enable IP
 | 
			
		||||
+forwarding on the Linux box, and add:
 | 
			
		||||
+.IP
 | 
			
		||||
+iptables -A FORWARD -p tcp -j TARPIT
 | 
			
		||||
+.IP
 | 
			
		||||
+iptables -A FORWARD -j DROP
 | 
			
		||||
+.TP
 | 
			
		||||
+NOTE:
 | 
			
		||||
+If you use the conntrack module while you are using TARPIT, you should
 | 
			
		||||
+also use the NOTRACK target, or the kernel will unnecessarily allocate
 | 
			
		||||
+resources for each TARPITted connection. To TARPIT incoming
 | 
			
		||||
+connections to the standard IRC port while using conntrack, you could:
 | 
			
		||||
+.IP
 | 
			
		||||
+iptables -t raw -A PREROUTING -p tcp --dport 6667 -j NOTRACK
 | 
			
		||||
+.IP
 | 
			
		||||
+iptables -A INPUT -p tcp --dport 6667 -j TARPIT
 | 
			
		||||
Index: iptables-1.4.0/extensions/.TARPIT-testx
 | 
			
		||||
===================================================================
 | 
			
		||||
--- /dev/null
 | 
			
		||||
+++ iptables-1.4.0/extensions/.TARPIT-testx
 | 
			
		||||
@@ -0,0 +1,2 @@
 | 
			
		||||
+#! /bin/sh
 | 
			
		||||
+[ -f "$KERNEL_DIR/net/netfilter/xt_TARPIT.c" ] && echo "TARPIT"
 | 
			
		||||
		Reference in New Issue
	
	Block a user