xref: /aosp_15_r20/external/iptables/extensions/libxt_helper.c (revision a71a954618bbadd4a345637e5edcf36eec826889)
1*a71a9546SAutomerger Merge Worker #include <stdio.h>
2*a71a9546SAutomerger Merge Worker #include <xtables.h>
3*a71a9546SAutomerger Merge Worker #include <linux/netfilter/xt_helper.h>
4*a71a9546SAutomerger Merge Worker 
5*a71a9546SAutomerger Merge Worker enum {
6*a71a9546SAutomerger Merge Worker 	O_HELPER = 0,
7*a71a9546SAutomerger Merge Worker };
8*a71a9546SAutomerger Merge Worker 
helper_help(void)9*a71a9546SAutomerger Merge Worker static void helper_help(void)
10*a71a9546SAutomerger Merge Worker {
11*a71a9546SAutomerger Merge Worker 	printf(
12*a71a9546SAutomerger Merge Worker "helper match options:\n"
13*a71a9546SAutomerger Merge Worker "[!] --helper string        Match helper identified by string\n");
14*a71a9546SAutomerger Merge Worker }
15*a71a9546SAutomerger Merge Worker 
16*a71a9546SAutomerger Merge Worker static const struct xt_option_entry helper_opts[] = {
17*a71a9546SAutomerger Merge Worker 	{.name = "helper", .id = O_HELPER, .type = XTTYPE_STRING,
18*a71a9546SAutomerger Merge Worker 	 .flags = XTOPT_MAND | XTOPT_INVERT | XTOPT_PUT,
19*a71a9546SAutomerger Merge Worker 	 XTOPT_POINTER(struct xt_helper_info, name)},
20*a71a9546SAutomerger Merge Worker 	XTOPT_TABLEEND,
21*a71a9546SAutomerger Merge Worker };
22*a71a9546SAutomerger Merge Worker 
helper_parse(struct xt_option_call * cb)23*a71a9546SAutomerger Merge Worker static void helper_parse(struct xt_option_call *cb)
24*a71a9546SAutomerger Merge Worker {
25*a71a9546SAutomerger Merge Worker 	struct xt_helper_info *info = cb->data;
26*a71a9546SAutomerger Merge Worker 
27*a71a9546SAutomerger Merge Worker 	xtables_option_parse(cb);
28*a71a9546SAutomerger Merge Worker 	if (cb->invert)
29*a71a9546SAutomerger Merge Worker 		info->invert = 1;
30*a71a9546SAutomerger Merge Worker }
31*a71a9546SAutomerger Merge Worker 
32*a71a9546SAutomerger Merge Worker static void
helper_print(const void * ip,const struct xt_entry_match * match,int numeric)33*a71a9546SAutomerger Merge Worker helper_print(const void *ip, const struct xt_entry_match *match, int numeric)
34*a71a9546SAutomerger Merge Worker {
35*a71a9546SAutomerger Merge Worker 	const struct xt_helper_info *info = (const void *)match->data;
36*a71a9546SAutomerger Merge Worker 
37*a71a9546SAutomerger Merge Worker 	printf(" helper match %s\"%s\"", info->invert ? "! " : "", info->name);
38*a71a9546SAutomerger Merge Worker }
39*a71a9546SAutomerger Merge Worker 
helper_save(const void * ip,const struct xt_entry_match * match)40*a71a9546SAutomerger Merge Worker static void helper_save(const void *ip, const struct xt_entry_match *match)
41*a71a9546SAutomerger Merge Worker {
42*a71a9546SAutomerger Merge Worker 	const struct xt_helper_info *info = (const void *)match->data;
43*a71a9546SAutomerger Merge Worker 
44*a71a9546SAutomerger Merge Worker 	printf("%s --helper", info->invert ? " !" : "");
45*a71a9546SAutomerger Merge Worker 	xtables_save_string(info->name);
46*a71a9546SAutomerger Merge Worker }
47*a71a9546SAutomerger Merge Worker 
helper_xlate(struct xt_xlate * xl,const struct xt_xlate_mt_params * params)48*a71a9546SAutomerger Merge Worker static int helper_xlate(struct xt_xlate *xl,
49*a71a9546SAutomerger Merge Worker 			const struct xt_xlate_mt_params *params)
50*a71a9546SAutomerger Merge Worker {
51*a71a9546SAutomerger Merge Worker 	const struct xt_helper_info *info = (const void *)params->match->data;
52*a71a9546SAutomerger Merge Worker 
53*a71a9546SAutomerger Merge Worker 	xt_xlate_add(xl, "ct helper%s \"%s\"",
54*a71a9546SAutomerger Merge Worker 		     info->invert ? " !=" : "", info->name);
55*a71a9546SAutomerger Merge Worker 
56*a71a9546SAutomerger Merge Worker 	return 1;
57*a71a9546SAutomerger Merge Worker }
58*a71a9546SAutomerger Merge Worker 
59*a71a9546SAutomerger Merge Worker static struct xtables_match helper_match = {
60*a71a9546SAutomerger Merge Worker 	.family		= NFPROTO_UNSPEC,
61*a71a9546SAutomerger Merge Worker 	.name		= "helper",
62*a71a9546SAutomerger Merge Worker 	.version	= XTABLES_VERSION,
63*a71a9546SAutomerger Merge Worker 	.size		= XT_ALIGN(sizeof(struct xt_helper_info)),
64*a71a9546SAutomerger Merge Worker 	.help		= helper_help,
65*a71a9546SAutomerger Merge Worker 	.print		= helper_print,
66*a71a9546SAutomerger Merge Worker 	.save		= helper_save,
67*a71a9546SAutomerger Merge Worker 	.x6_parse	= helper_parse,
68*a71a9546SAutomerger Merge Worker 	.x6_options	= helper_opts,
69*a71a9546SAutomerger Merge Worker 	.xlate		= helper_xlate,
70*a71a9546SAutomerger Merge Worker };
71*a71a9546SAutomerger Merge Worker 
_init(void)72*a71a9546SAutomerger Merge Worker void _init(void)
73*a71a9546SAutomerger Merge Worker {
74*a71a9546SAutomerger Merge Worker 	xtables_register_match(&helper_match);
75*a71a9546SAutomerger Merge Worker }
76