add XOR patch by Tim Vandermeersch

diff --git a/extensions/.XOR-test b/extensions/.XOR-test
new file mode 100755 (executable)
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 (file)
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);
+}