add XOR patch by Tim Vandermeersch
diff --git a/extensions/.XOR-test b/extensions/.XOR-test
new file mode 100755
index 0000000..92707da
--- /dev/null
+++ b/extensions/.XOR-test
@@ -0,0 +1,2 @@
+#! /bin/sh
+[ -f $KERNEL_DIR/net/ipv4/netfilter/ipt_XOR.c ] && echo XOR
diff --git a/extensions/libipt_XOR.c b/extensions/libipt_XOR.c
new file mode 100644
index 0000000..3b05a30
--- /dev/null
+++ b/extensions/libipt_XOR.c
@@ -0,0 +1,112 @@
+/* Shared library add-on to iptables for the XOR target
+ * (C) 2000 by Tim Vandermeersch <Tim.Vandermeersch@pandora.be>
+ * Based on libipt_TTL.c
+ *
+ * Version 1.0
+ *
+ * This program is distributed under the terms of GNU GPL
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <iptables.h>
+
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_XOR.h>
+
+#define IPT_KEY_SET 1
+#define IPT_BLOCKSIZE_SET 2
+
+static void init(struct ipt_entry_target *t, unsigned int *nfcache)
+{
+}
+
+static void help(void)
+{
+ printf(
+ "XOR target v%s options\n"
+ " --key string Set key to \"string\"\n"
+ " --block-size Set block size\n",
+ IPTABLES_VERSION);
+}
+
+static int parse(int c, char **argv, int invert, unsigned int *flags,
+ const struct ipt_entry *entry,
+ struct ipt_entry_target **target)
+{
+ struct ipt_XOR_info *info = (struct ipt_XOR_info *) (*target)->data;
+
+ if (!optarg)
+ exit_error(PARAMETER_PROBLEM, "XOR: too few arguments");
+
+ if (check_inverse(optarg, &invert, NULL, 0))
+ exit_error(PARAMETER_PROBLEM, "XOR: unexpected '!'");
+
+ switch (c) {
+ case '1':
+ strncpy(info->key, optarg, 30);
+ *flags |= IPT_KEY_SET;
+ break;
+ case '2':
+ info->block_size = atoi(optarg);
+ *flags |= IPT_BLOCKSIZE_SET;
+ break;
+ default:
+ return 0;
+ }
+
+ return 1;
+}
+
+static void final_check(unsigned int flags)
+{
+ if (!(flags & IPT_KEY_SET))
+ exit_error(PARAMETER_PROBLEM, "XOR: You must specify a key");
+ if (!(flags & IPT_BLOCKSIZE_SET))
+ exit_error(PARAMETER_PROBLEM, "XOR: You must specify a block-size");
+}
+
+static void save (const struct ipt_ip *ip,
+ const struct ipt_entry_target *target)
+{
+ const struct ipt_XOR_info *info = (struct ipt_XOR_info *) target->data;
+
+ printf("--key %s ", info->key);
+ printf("--block-size %u ", info->block_size);
+}
+
+static void print (const struct ipt_ip *ip,
+ const struct ipt_entry_target *target, int numeric)
+{
+ const struct ipt_XOR_info *info = (struct ipt_XOR_info *) target->data;
+
+ printf("key: %s ", info->key);
+ printf("block-size: %u ", info->block_size);
+}
+
+static struct option opts[] = {
+ { "key", 1, 0, '1' },
+ { "block-size", 1, 0, '2' },
+ { 0 }
+};
+
+static struct iptables_target XOR = { NULL,
+ "XOR",
+ IPTABLES_VERSION,
+ IPT_ALIGN(sizeof(struct ipt_XOR_info)),
+ IPT_ALIGN(sizeof(struct ipt_XOR_info)),
+ &help,
+ &init,
+ &parse,
+ &final_check,
+ &print,
+ &save,
+ opts
+};
+
+void _init(void)
+{
+ register_target(&XOR);
+}