1/* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
2 *                         Patrick Schaaf <bof@bof.de>
3 *                         Martin Josefsson <gandalf@wlug.westbo.se>
4 * Copyright (C) 2003-2004 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11/* Shared library add-on to iptables to add IP set mangling target. */
12#include <stdio.h>
13#include <netdb.h>
14#include <string.h>
15#include <stdlib.h>
16#include <getopt.h>
17#include <ctype.h>
18
19#include <iptables.h>
20#include <linux/netfilter_ipv4/ip_tables.h>
21#include <linux/netfilter_ipv4/ip_set.h>
22#include <linux/netfilter_ipv4/ipt_set.h>
23#include "libipt_set.h"
24
25/* Function which prints out usage message. */
26static void help(void)
27{
28	printf("SET v%s options:\n"
29	       " --add-set name flags\n"
30	       " --del-set name flags\n"
31	       "		add/del src/dst IP/port from/to named sets,\n"
32	       "		where flags are the comma separated list of\n"
33	       "		'src' and 'dst'.\n"
34	       "\n", IPTABLES_VERSION);
35}
36
37static struct option opts[] = {
38	{"add-set",   1, 0, '1'},
39	{"del-set",   1, 0, '2'},
40	{0}
41};
42
43/* Initialize the target. */
44static void init(struct ipt_entry_target *target, unsigned int *nfcache)
45{
46	struct ipt_set_info_target *info =
47	    (struct ipt_set_info_target *) target->data;
48
49	memset(info, 0, sizeof(struct ipt_set_info_target));
50	info->add_set.index =
51	info->del_set.index = IP_SET_INVALID_ID;
52
53}
54
55static void
56parse_target(char **argv, int invert, unsigned int *flags,
57             struct ipt_set_info *info, const char *what)
58{
59	if (info->flags[0])
60		exit_error(PARAMETER_PROBLEM,
61			   "--%s can be specified only once", what);
62
63	if (check_inverse(optarg, &invert, NULL, 0))
64		exit_error(PARAMETER_PROBLEM,
65			   "Unexpected `!' after --%s", what);
66
67	if (!argv[optind]
68	    || argv[optind][0] == '-' || argv[optind][0] == '!')
69		exit_error(PARAMETER_PROBLEM,
70			   "--%s requires two args.", what);
71
72	if (strlen(argv[optind-1]) > IP_SET_MAXNAMELEN - 1)
73		exit_error(PARAMETER_PROBLEM,
74			   "setname `%s' too long, max %d characters.",
75			   argv[optind-1], IP_SET_MAXNAMELEN - 1);
76
77	get_set_byname(argv[optind - 1], info);
78	parse_bindings(argv[optind], info);
79	optind++;
80
81	*flags = 1;
82}
83
84/* Function which parses command options; returns true if it
85   ate an option */
86static int
87parse(int c, char **argv, int invert, unsigned int *flags,
88      const struct ipt_entry *entry, struct ipt_entry_target **target)
89{
90	struct ipt_set_info_target *myinfo =
91	    (struct ipt_set_info_target *) (*target)->data;
92
93	switch (c) {
94	case '1':		/* --add-set <set> <flags> */
95		parse_target(argv, invert, flags,
96			     &myinfo->add_set, "add-set");
97		break;
98	case '2':		/* --del-set <set>[:<flags>] <flags> */
99		parse_target(argv, invert, flags,
100			     &myinfo->del_set, "del-set");
101		break;
102
103	default:
104		return 0;
105	}
106	return 1;
107}
108
109/* Final check; must specify at least one. */
110static void final_check(unsigned int flags)
111{
112	if (!flags)
113		exit_error(PARAMETER_PROBLEM,
114			   "You must specify either `--add-set' or `--del-set'");
115}
116
117static void
118print_target(const char *prefix, const struct ipt_set_info *info)
119{
120	int i;
121	char setname[IP_SET_MAXNAMELEN];
122
123	if (info->index == IP_SET_INVALID_ID)
124		return;
125	get_set_byid(setname, info->index);
126	printf("%s %s", prefix, setname);
127	for (i = 0; i < IP_SET_MAX_BINDINGS; i++) {
128		if (!info->flags[i])
129			break;
130		printf("%s%s",
131		       i == 0 ? " " : ",",
132		       info->flags[i] & IPSET_SRC ? "src" : "dst");
133	}
134	printf(" ");
135}
136
137/* Prints out the targinfo. */
138static void
139print(const struct ipt_ip *ip,
140      const struct ipt_entry_target *target, int numeric)
141{
142	struct ipt_set_info_target *info =
143	    (struct ipt_set_info_target *) target->data;
144
145	print_target("add-set", &info->add_set);
146	print_target("del-set", &info->del_set);
147}
148
149/* Saves the union ipt_targinfo in parsable form to stdout. */
150static void
151save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
152{
153	struct ipt_set_info_target *info =
154	    (struct ipt_set_info_target *) target->data;
155
156	print_target("--add-set", &info->add_set);
157	print_target("--del-set", &info->del_set);
158}
159
160static
161struct iptables_target ipt_set_target
162= {
163	.name		= "SET",
164	.version	= IPTABLES_VERSION,
165	.size		= IPT_ALIGN(sizeof(struct ipt_set_info_target)),
166	.userspacesize	= IPT_ALIGN(sizeof(struct ipt_set_info_target)),
167	.help		= &help,
168	.init		= &init,
169	.parse		= &parse,
170	.final_check	= &final_check,
171	.print		= &print,
172	.save		= &save,
173	.extra_opts	= opts
174};
175
176void _init(void)
177{
178	register_target(&ipt_set_target);
179}
180