libip6t_mh.c revision 73866357e4a7a0fdc1b293bf8863fee2bd56da9e 
1/* Shared library add-on to ip6tables to add mobility header support. */
2/*
3 * Copyright (C)2006 USAGI/WIDE Project
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Author:
10 *	Masahide NAKAMURA @USAGI <masahide.nakamura.cz@hitachi.com>
11 *
12 * Based on libip6t_{icmpv6,udp}.c
13 */
14#include <stdbool.h>
15#include <stdio.h>
16#include <netdb.h>
17#include <string.h>
18#include <stdlib.h>
19#include <getopt.h>
20#include <xtables.h>
21#include <linux/netfilter_ipv6/ip6t_mh.h>
22
23struct mh_name {
24	const char *name;
25	uint8_t type;
26};
27
28static const struct mh_name mh_names[] = {
29	{ "binding-refresh-request", 0, },
30	/* Alias */ { "brr", 0, },
31	{ "home-test-init", 1, },
32	/* Alias */ { "hoti", 1, },
33	{ "careof-test-init", 2, },
34	/* Alias */ { "coti", 2, },
35	{ "home-test", 3, },
36	/* Alias */ { "hot", 3, },
37	{ "careof-test", 4, },
38	/* Alias */ { "cot", 4, },
39	{ "binding-update", 5, },
40	/* Alias */ { "bu", 5, },
41	{ "binding-acknowledgement", 6, },
42	/* Alias */ { "ba", 6, },
43	{ "binding-error", 7, },
44	/* Alias */ { "be", 7, },
45};
46
47static void print_types_all(void)
48{
49	unsigned int i;
50	printf("Valid MH types:");
51
52	for (i = 0; i < ARRAY_SIZE(mh_names); ++i) {
53		if (i && mh_names[i].type == mh_names[i-1].type)
54			printf(" (%s)", mh_names[i].name);
55		else
56			printf("\n%s", mh_names[i].name);
57	}
58	printf("\n");
59}
60
61static void mh_help(void)
62{
63	printf(
64"mh match options:\n"
65"[!] --mh-type type[:type]	match mh type\n");
66	print_types_all();
67}
68
69static void mh_init(struct xt_entry_match *m)
70{
71	struct ip6t_mh *mhinfo = (struct ip6t_mh *)m->data;
72
73	mhinfo->types[1] = 0xFF;
74}
75
76static unsigned int name_to_type(const char *name)
77{
78	int namelen = strlen(name);
79	static const unsigned int limit = ARRAY_SIZE(mh_names);
80	unsigned int match = limit;
81	unsigned int i;
82
83	for (i = 0; i < limit; i++) {
84		if (strncasecmp(mh_names[i].name, name, namelen) == 0) {
85			int len = strlen(mh_names[i].name);
86			if (match == limit || len == namelen)
87				match = i;
88		}
89	}
90
91	if (match != limit) {
92		return mh_names[match].type;
93	} else {
94		unsigned int number;
95
96		if (!xtables_strtoui(name, NULL, &number, 0, UINT8_MAX))
97			xtables_error(PARAMETER_PROBLEM,
98				   "Invalid MH type `%s'\n", name);
99		return number;
100	}
101}
102
103static void parse_mh_types(const char *mhtype, uint8_t *types)
104{
105	char *buffer;
106	char *cp;
107
108	buffer = strdup(mhtype);
109	if ((cp = strchr(buffer, ':')) == NULL)
110		types[0] = types[1] = name_to_type(buffer);
111	else {
112		*cp = '\0';
113		cp++;
114
115		types[0] = buffer[0] ? name_to_type(buffer) : 0;
116		types[1] = cp[0] ? name_to_type(cp) : 0xFF;
117
118		if (types[0] > types[1])
119			xtables_error(PARAMETER_PROBLEM,
120				   "Invalid MH type range (min > max)");
121	}
122	free(buffer);
123}
124
125#define MH_TYPES 0x01
126
127static int mh_parse(int c, char **argv, int invert, unsigned int *flags,
128                    const void *entry, struct xt_entry_match **match)
129{
130	struct ip6t_mh *mhinfo = (struct ip6t_mh *)(*match)->data;
131
132	switch (c) {
133	case '1':
134		if (*flags & MH_TYPES)
135			xtables_error(PARAMETER_PROBLEM,
136				   "Only one `--mh-type' allowed");
137		xtables_check_inverse(optarg, &invert, &optind, 0, argv);
138		parse_mh_types(optarg, mhinfo->types);
139		if (invert)
140			mhinfo->invflags |= IP6T_MH_INV_TYPE;
141		*flags |= MH_TYPES;
142		break;
143	}
144
145	return 1;
146}
147
148static const char *type_to_name(uint8_t type)
149{
150	unsigned int i;
151
152	for (i = 0; i < ARRAY_SIZE(mh_names); ++i)
153		if (mh_names[i].type == type)
154			return mh_names[i].name;
155
156	return NULL;
157}
158
159static void print_type(uint8_t type, int numeric)
160{
161	const char *name;
162	if (numeric || !(name = type_to_name(type)))
163		printf("%u", type);
164	else
165		printf("%s", name);
166}
167
168static void print_types(uint8_t min, uint8_t max, int invert, int numeric)
169{
170	const char *inv = invert ? "!" : "";
171
172	if (min != 0 || max != 0xFF || invert) {
173		printf(" ");
174		if (min == max) {
175			printf("%s", inv);
176			print_type(min, numeric);
177		} else {
178			printf("%s", inv);
179			print_type(min, numeric);
180			printf(":");
181			print_type(max, numeric);
182		}
183	}
184}
185
186static void mh_print(const void *ip, const struct xt_entry_match *match,
187                     int numeric)
188{
189	const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
190
191	printf(" mh");
192	print_types(mhinfo->types[0], mhinfo->types[1],
193		    mhinfo->invflags & IP6T_MH_INV_TYPE,
194		    numeric);
195	if (mhinfo->invflags & ~IP6T_MH_INV_MASK)
196		printf(" Unknown invflags: 0x%X",
197		       mhinfo->invflags & ~IP6T_MH_INV_MASK);
198}
199
200static void mh_save(const void *ip, const struct xt_entry_match *match)
201{
202	const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
203
204	if (mhinfo->types[0] == 0 && mhinfo->types[1] == 0xFF)
205		return;
206
207	if (mhinfo->invflags & IP6T_MH_INV_TYPE)
208		printf(" !");
209
210	if (mhinfo->types[0] != mhinfo->types[1])
211		printf(" --mh-type %u:%u", mhinfo->types[0], mhinfo->types[1]);
212	else
213		printf(" --mh-type %u", mhinfo->types[0]);
214}
215
216static const struct option mh_opts[] = {
217	{.name = "mh-type", .has_arg = true, .val = '1'},
218	XT_GETOPT_TABLEEND,
219};
220
221static struct xtables_match mh_mt6_reg = {
222	.name		= "mh",
223	.version	= XTABLES_VERSION,
224	.family		= NFPROTO_IPV6,
225	.size		= XT_ALIGN(sizeof(struct ip6t_mh)),
226	.userspacesize	= XT_ALIGN(sizeof(struct ip6t_mh)),
227	.help		= mh_help,
228	.init		= mh_init,
229	.parse		= mh_parse,
230	.print		= mh_print,
231	.save		= mh_save,
232	.extra_opts	= mh_opts,
233};
234
235void _init(void)
236{
237	xtables_register_match(&mh_mt6_reg);
238}
239