libxt_dscp.c revision c5e85736c207f211d82d2878a5781f512327dfce 
1/* Shared library add-on to iptables for DSCP
2 *
3 * (C) 2002 by Harald Welte <laforge@gnumonks.org>
4 *
5 * This program is distributed under the terms of GNU GPL v2, 1991
6 *
7 * libipt_dscp.c borrowed heavily from libipt_tos.c
8 *
9 * --class support added by Iain Barnes
10 *
11 * For a list of DSCP codepoints see
12 * http://www.iana.org/assignments/dscp-registry
13 *
14 */
15#include <stdio.h>
16#include <string.h>
17#include <stdlib.h>
18#include <getopt.h>
19
20#include <xtables.h>
21#include <linux/netfilter/x_tables.h>
22#include <linux/netfilter/xt_dscp.h>
23
24/* This is evil, but it's my code - HW*/
25#include "dscp_helper.c"
26
27static void dscp_help(void)
28{
29	printf(
30"dscp match options\n"
31"[!] --dscp value		Match DSCP codepoint with numerical value\n"
32"  		                This value can be in decimal (ex: 32)\n"
33"               		or in hex (ex: 0x20)\n"
34"[!] --dscp-class name		Match the DiffServ class. This value may\n"
35"				be any of the BE,EF, AFxx or CSx classes\n"
36"\n"
37"				These two options are mutually exclusive !\n");
38}
39
40static const struct option dscp_opts[] = {
41	{ "dscp", 1, NULL, 'F' },
42	{ "dscp-class", 1, NULL, 'G' },
43	{ .name = NULL }
44};
45
46static void
47parse_dscp(const char *s, struct xt_dscp_info *dinfo)
48{
49	unsigned int dscp;
50
51	if (!xtables_strtoui(s, NULL, &dscp, 0, UINT8_MAX))
52		xtables_error(PARAMETER_PROBLEM,
53			   "Invalid dscp `%s'\n", s);
54
55	if (dscp > XT_DSCP_MAX)
56		xtables_error(PARAMETER_PROBLEM,
57			   "DSCP `%d` out of range\n", dscp);
58
59	dinfo->dscp = dscp;
60}
61
62
63static void
64parse_class(const char *s, struct xt_dscp_info *dinfo)
65{
66	unsigned int dscp = class_to_dscp(s);
67
68	/* Assign the value */
69	dinfo->dscp = dscp;
70}
71
72
73static int
74dscp_parse(int c, char **argv, int invert, unsigned int *flags,
75           const void *entry, struct xt_entry_match **match)
76{
77	struct xt_dscp_info *dinfo
78		= (struct xt_dscp_info *)(*match)->data;
79
80	switch (c) {
81	case 'F':
82		if (*flags)
83			xtables_error(PARAMETER_PROBLEM,
84			           "DSCP match: Only use --dscp ONCE!");
85		xtables_check_inverse(optarg, &invert, &optind, 0);
86		parse_dscp(argv[optind-1], dinfo);
87		if (invert)
88			dinfo->invert = 1;
89		*flags = 1;
90		break;
91
92	case 'G':
93		if (*flags)
94			xtables_error(PARAMETER_PROBLEM,
95					"DSCP match: Only use --dscp-class ONCE!");
96		xtables_check_inverse(optarg, &invert, &optind, 0);
97		parse_class(argv[optind - 1], dinfo);
98		if (invert)
99			dinfo->invert = 1;
100		*flags = 1;
101		break;
102
103	default:
104		return 0;
105	}
106
107	return 1;
108}
109
110static void dscp_check(unsigned int flags)
111{
112	if (!flags)
113		xtables_error(PARAMETER_PROBLEM,
114		           "DSCP match: Parameter --dscp is required");
115}
116
117static void
118dscp_print(const void *ip, const struct xt_entry_match *match, int numeric)
119{
120	const struct xt_dscp_info *dinfo =
121		(const struct xt_dscp_info *)match->data;
122	printf("DSCP match %s0x%02x", dinfo->invert ? "!" : "", dinfo->dscp);
123}
124
125static void dscp_save(const void *ip, const struct xt_entry_match *match)
126{
127	const struct xt_dscp_info *dinfo =
128		(const struct xt_dscp_info *)match->data;
129
130	printf("%s--dscp 0x%02x ", dinfo->invert ? "! " : "", dinfo->dscp);
131}
132
133static struct xtables_match dscp_match = {
134	.family		= NFPROTO_UNSPEC,
135	.name 		= "dscp",
136	.version 	= XTABLES_VERSION,
137	.size 		= XT_ALIGN(sizeof(struct xt_dscp_info)),
138	.userspacesize	= XT_ALIGN(sizeof(struct xt_dscp_info)),
139	.help		= dscp_help,
140	.parse		= dscp_parse,
141	.final_check	= dscp_check,
142	.print		= dscp_print,
143	.save		= dscp_save,
144	.extra_opts	= dscp_opts,
145};
146
147void _init(void)
148{
149	xtables_register_match(&dscp_match);
150}
151