libip6t_mh.c revision bf97128c7262f17a02fec41cdae75b472ba77f88 
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 <stdio.h>
15#include <netdb.h>
16#include <string.h>
17#include <stdlib.h>
18#include <getopt.h>
19#include <xtables.h>
20#include <linux/netfilter_ipv6/ip6t_mh.h>
21
22struct mh_name {
23	const char *name;
24	u_int8_t type;
25};
26
27static const struct mh_name mh_names[] = {
28	{ "binding-refresh-request", 0, },
29	/* Alias */ { "brr", 0, },
30	{ "home-test-init", 1, },
31	/* Alias */ { "hoti", 1, },
32	{ "careof-test-init", 2, },
33	/* Alias */ { "coti", 2, },
34	{ "home-test", 3, },
35	/* Alias */ { "hot", 3, },
36	{ "careof-test", 4, },
37	/* Alias */ { "cot", 4, },
38	{ "binding-update", 5, },
39	/* Alias */ { "bu", 5, },
40	{ "binding-acknowledgement", 6, },
41	/* Alias */ { "ba", 6, },
42	{ "binding-error", 7, },
43	/* Alias */ { "be", 7, },
44};
45
46static void print_types_all(void)
47{
48	unsigned int i;
49	printf("Valid MH types:");
50
51	for (i = 0; i < ARRAY_SIZE(mh_names); ++i) {
52		if (i && mh_names[i].type == mh_names[i-1].type)
53			printf(" (%s)", mh_names[i].name);
54		else
55			printf("\n%s", mh_names[i].name);
56	}
57	printf("\n");
58}
59
60static void mh_help(void)
61{
62	printf(
63"mh match options:\n"
64"[!] --mh-type type[:type]	match mh type\n");
65	print_types_all();
66}
67
68static void mh_init(struct xt_entry_match *m)
69{
70	struct ip6t_mh *mhinfo = (struct ip6t_mh *)m->data;
71
72	mhinfo->types[1] = 0xFF;
73}
74
75static unsigned int name_to_type(const char *name)
76{
77	int namelen = strlen(name);
78	static const unsigned int limit = ARRAY_SIZE(mh_names);
79	unsigned int match = limit;
80	unsigned int i;
81
82	for (i = 0; i < limit; i++) {
83		if (strncasecmp(mh_names[i].name, name, namelen) == 0) {
84			int len = strlen(mh_names[i].name);
85			if (match == limit || len == namelen)
86				match = i;
87		}
88	}
89
90	if (match != limit) {
91		return mh_names[match].type;
92	} else {
93		unsigned int number;
94
95		if (!xtables_strtoui(name, NULL, &number, 0, UINT8_MAX))
96			xtables_error(PARAMETER_PROBLEM,
97				   "Invalid MH type `%s'\n", name);
98		return number;
99	}
100}
101
102static void parse_mh_types(const char *mhtype, u_int8_t *types)
103{
104	char *buffer;
105	char *cp;
106
107	buffer = strdup(mhtype);
108	if ((cp = strchr(buffer, ':')) == NULL)
109		types[0] = types[1] = name_to_type(buffer);
110	else {
111		*cp = '\0';
112		cp++;
113
114		types[0] = buffer[0] ? name_to_type(buffer) : 0;
115		types[1] = cp[0] ? name_to_type(cp) : 0xFF;
116
117		if (types[0] > types[1])
118			xtables_error(PARAMETER_PROBLEM,
119				   "Invalid MH type range (min > max)");
120	}
121	free(buffer);
122}
123
124#define MH_TYPES 0x01
125
126static int mh_parse(int c, char **argv, int invert, unsigned int *flags,
127                    const void *entry, struct xt_entry_match **match)
128{
129	struct ip6t_mh *mhinfo = (struct ip6t_mh *)(*match)->data;
130
131	switch (c) {
132	case '1':
133		if (*flags & MH_TYPES)
134			xtables_error(PARAMETER_PROBLEM,
135				   "Only one `--mh-type' allowed");
136		xtables_check_inverse(optarg, &invert, &optind, 0, argv);
137		parse_mh_types(argv[optind-1], mhinfo->types);
138		if (invert)
139			mhinfo->invflags |= IP6T_MH_INV_TYPE;
140		*flags |= MH_TYPES;
141		break;
142
143	default:
144		return 0;
145	}
146
147	return 1;
148}
149
150static const char *type_to_name(u_int8_t type)
151{
152	unsigned int i;
153
154	for (i = 0; i < ARRAY_SIZE(mh_names); ++i)
155		if (mh_names[i].type == type)
156			return mh_names[i].name;
157
158	return NULL;
159}
160
161static void print_type(u_int8_t type, int numeric)
162{
163	const char *name;
164	if (numeric || !(name = type_to_name(type)))
165		printf("%u", type);
166	else
167		printf("%s", name);
168}
169
170static void print_types(u_int8_t min, u_int8_t max, int invert, int numeric)
171{
172	const char *inv = invert ? "!" : "";
173
174	if (min != 0 || max != 0xFF || invert) {
175		if (min == max) {
176			printf("%s", inv);
177			print_type(min, numeric);
178		} else {
179			printf("%s", inv);
180			print_type(min, numeric);
181			printf(":");
182			print_type(max, numeric);
183		}
184		printf(" ");
185	}
186}
187
188static void mh_print(const void *ip, const struct xt_entry_match *match,
189                     int numeric)
190{
191	const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
192
193	printf("mh ");
194	print_types(mhinfo->types[0], mhinfo->types[1],
195		    mhinfo->invflags & IP6T_MH_INV_TYPE,
196		    numeric);
197	if (mhinfo->invflags & ~IP6T_MH_INV_MASK)
198		printf("Unknown invflags: 0x%X ",
199		       mhinfo->invflags & ~IP6T_MH_INV_MASK);
200}
201
202static void mh_save(const void *ip, const struct xt_entry_match *match)
203{
204	const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
205
206	if (mhinfo->types[0] == 0 && mhinfo->types[1] == 0xFF)
207		return;
208
209	if (mhinfo->invflags & IP6T_MH_INV_TYPE)
210		printf("! ");
211
212	if (mhinfo->types[0] != mhinfo->types[1])
213		printf("--mh-type %u:%u ", mhinfo->types[0], mhinfo->types[1]);
214	else
215		printf("--mh-type %u ", mhinfo->types[0]);
216}
217
218static const struct option mh_opts[] = {
219	{ "mh-type", 1, NULL, '1' },
220	{ .name = NULL }
221};
222
223static struct xtables_match mh_mt6_reg = {
224	.name		= "mh",
225	.version	= XTABLES_VERSION,
226	.family		= NFPROTO_IPV6,
227	.size		= XT_ALIGN(sizeof(struct ip6t_mh)),
228	.userspacesize	= XT_ALIGN(sizeof(struct ip6t_mh)),
229	.help		= mh_help,
230	.init		= mh_init,
231	.parse		= mh_parse,
232	.print		= mh_print,
233	.save		= mh_save,
234	.extra_opts	= mh_opts,
235};
236
237void _init(void)
238{
239	xtables_register_match(&mh_mt6_reg);
240}
241