summaryrefslogtreecommitdiffstats
path: root/extensions/libxt_dscp.c
blob: 6aed4990cc0dfaf45df211e5c191b20789e1d37b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* Shared library add-on to iptables for DSCP
 *
 * (C) 2002 by Harald Welte <laforge@gnumonks.org>
 *
 * This program is distributed under the terms of GNU GPL v2, 1991
 *
 * libipt_dscp.c borrowed heavily from libipt_tos.c
 *
 * --class support added by Iain Barnes
 * 
 * For a list of DSCP codepoints see 
 * http://www.iana.org/assignments/dscp-registry
 *
 */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>

#include <xtables.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_dscp.h>

/* This is evil, but it's my code - HW*/
#include "dscp_helper.c"

static void dscp_help(void)
{
	printf(
"dscp match options\n"
"[!] --dscp value		Match DSCP codepoint with numerical value\n"
"  		                This value can be in decimal (ex: 32)\n"
"               		or in hex (ex: 0x20)\n"
"[!] --dscp-class name		Match the DiffServ class. This value may\n"
"				be any of the BE,EF, AFxx or CSx classes\n"
"\n"
"				These two options are mutually exclusive !\n");
}

static const struct option dscp_opts[] = {
	{ "dscp", 1, NULL, 'F' },
	{ "dscp-class", 1, NULL, 'G' },
	{ .name = NULL }
};

static void
parse_dscp(const char *s, struct xt_dscp_info *dinfo)
{
	unsigned int dscp;
       
	if (string_to_number(s, 0, 255, &dscp) == -1)
		exit_error(PARAMETER_PROBLEM,
			   "Invalid dscp `%s'\n", s);

	if (dscp > XT_DSCP_MAX)
		exit_error(PARAMETER_PROBLEM,
			   "DSCP `%d` out of range\n", dscp);

    	dinfo->dscp = (u_int8_t )dscp;
    	return;
}


static void
parse_class(const char *s, struct xt_dscp_info *dinfo)
{
	unsigned int dscp = class_to_dscp(s);

	/* Assign the value */
	dinfo->dscp = (u_int8_t)dscp;
}


static int
dscp_parse(int c, char **argv, int invert, unsigned int *flags,
           const void *entry, struct xt_entry_match **match)
{
	struct xt_dscp_info *dinfo
		= (struct xt_dscp_info *)(*match)->data;

	switch (c) {
	case 'F':
		if (*flags)
			exit_error(PARAMETER_PROBLEM,
			           "DSCP match: Only use --dscp ONCE!");
		check_inverse(optarg, &invert, &optind, 0);
		parse_dscp(argv[optind-1], dinfo);
		if (invert)
			dinfo->invert = 1;
		*flags = 1;
		break;

	case 'G':
		if (*flags)
			exit_error(PARAMETER_PROBLEM,
					"DSCP match: Only use --dscp-class ONCE!");
		check_inverse(optarg, &invert, &optind, 0);
		parse_class(argv[optind - 1], dinfo);
		if (invert)
			dinfo->invert = 1;
		*flags = 1;
		break;

	default:
		return 0;
	}

	return 1;
}

static void dscp_check(unsigned int flags)
{
	if (!flags)
		exit_error(PARAMETER_PROBLEM,
		           "DSCP match: Parameter --dscp is required");
}

static void
print_dscp(u_int8_t dscp, int invert, int numeric)
{
	if (invert)
		fputc('!', stdout);

 	printf("0x%02x ", dscp);
}

/* Prints out the matchinfo. */
static void
dscp_print(const void *ip, const struct xt_entry_match *match, int numeric)
{
	const struct xt_dscp_info *dinfo =
		(const struct xt_dscp_info *)match->data;
	printf("DSCP match ");
	print_dscp(dinfo->dscp, dinfo->invert, numeric);
}

/* Saves the union ipt_matchinfo in parsable form to stdout. */
static void dscp_save(const void *ip, const struct xt_entry_match *match)
{
	const struct xt_dscp_info *dinfo =
		(const struct xt_dscp_info *)match->data;

	printf("--dscp ");
	print_dscp(dinfo->dscp, dinfo->invert, 1);
}

static struct xtables_match dscp_match = {
	.family		= AF_INET,
	.name 		= "dscp",
	.version 	= XTABLES_VERSION,
	.size 		= XT_ALIGN(sizeof(struct xt_dscp_info)),
	.userspacesize	= XT_ALIGN(sizeof(struct xt_dscp_info)),
	.help		= dscp_help,
	.parse		= dscp_parse,
	.final_check	= dscp_check,
	.print		= dscp_print,
	.save		= dscp_save,
	.extra_opts	= dscp_opts,
};

static struct xtables_match dscp_match6 = {
	.family		= AF_INET6,
	.name 		= "dscp",
	.version 	= XTABLES_VERSION,
	.size 		= XT_ALIGN(sizeof(struct xt_dscp_info)),
	.userspacesize	= XT_ALIGN(sizeof(struct xt_dscp_info)),
	.help		= dscp_help,
	.parse		= dscp_parse,
	.final_check	= dscp_check,
	.print		= dscp_print,
	.save		= dscp_save,
	.extra_opts	= dscp_opts,
};

void _init(void)
{
	xtables_register_match(&dscp_match);
	xtables_register_match(&dscp_match6);
}