1 files changed, 77 insertions, 0 deletions
diff --git a/extensions/libxt_CHECKSUM.c b/extensions/libxt_CHECKSUM.c
new file mode 100644
index 0000000..df9f9b3
--- /dev/null
+++ b/extensions/libxt_CHECKSUM.c
@@ -0,0 +1,77 @@
+/* Shared library add-on to xtables for CHECKSUM
+ *
+ * (C) 2002 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010 by Red Hat, Inc
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *
+ * This program is distributed under the terms of GNU GPL v2, 1991
+ *
+ * libxt_CHECKSUM.c borrowed some bits from libipt_ECN.c
+ */
+#include <stdio.h>
+#include <xtables.h>
+#include <linux/netfilter/xt_CHECKSUM.h>
+
+enum {
+	O_CHECKSUM_FILL = 0,
+};
+
+static void CHECKSUM_help(void)
+{
+	printf(
+"CHECKSUM target options\n"
+"  --checksum-fill			Fill in packet checksum.\n");
+}
+
+static const struct xt_option_entry CHECKSUM_opts[] = {
+	{.name = "checksum-fill", .id = O_CHECKSUM_FILL,
+	 .flags = XTOPT_MAND, .type = XTTYPE_NONE},
+	XTOPT_TABLEEND,
+};
+
+static void CHECKSUM_parse(struct xt_option_call *cb)
+{
+	struct xt_CHECKSUM_info *einfo = cb->data;
+
+	xtables_option_parse(cb);
+	einfo->operation = XT_CHECKSUM_OP_FILL;
+}
+
+static void CHECKSUM_print(const void *ip, const struct xt_entry_target *target,
+                      int numeric)
+{
+	const struct xt_CHECKSUM_info *einfo =
+		(const struct xt_CHECKSUM_info *)target->data;
+
+	printf(" CHECKSUM");
+
+	if (einfo->operation & XT_CHECKSUM_OP_FILL)
+		printf(" fill");
+}
+
+static void CHECKSUM_save(const void *ip, const struct xt_entry_target *target)
+{
+	const struct xt_CHECKSUM_info *einfo =
+		(const struct xt_CHECKSUM_info *)target->data;
+
+	if (einfo->operation & XT_CHECKSUM_OP_FILL)
+		printf(" --checksum-fill");
+}
+
+static struct xtables_target checksum_tg_reg = {
+	.name		= "CHECKSUM",
+	.version	= XTABLES_VERSION,
+	.family		= NFPROTO_UNSPEC,
+	.size		= XT_ALIGN(sizeof(struct xt_CHECKSUM_info)),
+	.userspacesize	= XT_ALIGN(sizeof(struct xt_CHECKSUM_info)),
+	.help		= CHECKSUM_help,
+	.print		= CHECKSUM_print,
+	.save		= CHECKSUM_save,
+	.x6_parse	= CHECKSUM_parse,
+	.x6_options	= CHECKSUM_opts,
+};
+
+void _init(void)
+{
+	xtables_register_target(&checksum_tg_reg);
+}