1/* Shared library add-on to xtables for CHECKSUM
2 *
3 * (C) 2002 by Harald Welte <laforge@gnumonks.org>
4 * (C) 2010 by Red Hat, Inc
5 * Author: Michael S. Tsirkin <mst@redhat.com>
6 *
7 * This program is distributed under the terms of GNU GPL v2, 1991
8 *
9 * libxt_CHECKSUM.c borrowed some bits from libipt_ECN.c
10 */
11#include <stdio.h>
12#include <xtables.h>
13#include <linux/netfilter/xt_CHECKSUM.h>
14
15enum {
16	O_CHECKSUM_FILL = 0,
17};
18
19static void CHECKSUM_help(void)
20{
21	printf(
22"CHECKSUM target options\n"
23"  --checksum-fill			Fill in packet checksum.\n");
24}
25
26static const struct xt_option_entry CHECKSUM_opts[] = {
27	{.name = "checksum-fill", .id = O_CHECKSUM_FILL,
28	 .flags = XTOPT_MAND, .type = XTTYPE_NONE},
29	XTOPT_TABLEEND,
30};
31
32static void CHECKSUM_parse(struct xt_option_call *cb)
33{
34	struct xt_CHECKSUM_info *einfo = cb->data;
35
36	xtables_option_parse(cb);
37	einfo->operation = XT_CHECKSUM_OP_FILL;
38}
39
40static void CHECKSUM_print(const void *ip, const struct xt_entry_target *target,
41                      int numeric)
42{
43	const struct xt_CHECKSUM_info *einfo =
44		(const struct xt_CHECKSUM_info *)target->data;
45
46	printf(" CHECKSUM");
47
48	if (einfo->operation & XT_CHECKSUM_OP_FILL)
49		printf(" fill");
50}
51
52static void CHECKSUM_save(const void *ip, const struct xt_entry_target *target)
53{
54	const struct xt_CHECKSUM_info *einfo =
55		(const struct xt_CHECKSUM_info *)target->data;
56
57	if (einfo->operation & XT_CHECKSUM_OP_FILL)
58		printf(" --checksum-fill");
59}
60
61static struct xtables_target checksum_tg_reg = {
62	.name		= "CHECKSUM",
63	.version	= XTABLES_VERSION,
64	.family		= NFPROTO_UNSPEC,
65	.size		= XT_ALIGN(sizeof(struct xt_CHECKSUM_info)),
66	.userspacesize	= XT_ALIGN(sizeof(struct xt_CHECKSUM_info)),
67	.help		= CHECKSUM_help,
68	.print		= CHECKSUM_print,
69	.save		= CHECKSUM_save,
70	.x6_parse	= CHECKSUM_parse,
71	.x6_options	= CHECKSUM_opts,
72};
73
74void _init(void)
75{
76	xtables_register_target(&checksum_tg_reg);
77}
78