summaryrefslogtreecommitdiffstats
path: root/extensions/libct_proto_sctp.c
blob: 5e96dc1055fb9e6264f2d8c2d5a3d96eef0daaab (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
/*
 * (C) 2005 by Harald Welte <laforge@netfilter.org>
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 */
#include <stdio.h>
#include <getopt.h>
#include <stdlib.h>
#include <string.h>
#include <netinet/in.h> /* For htons */
#include "conntrack.h"
#include <libnetfilter_conntrack/libnetfilter_conntrack.h>

static struct option opts[] = {
	{"orig-port-src", 1, 0, '1'},
	{"orig-port-dst", 1, 0, '2'},
	{"reply-port-src", 1, 0, '3'},
	{"reply-port-dst", 1, 0, '4'},
	{"state", 1, 0, '7'},
	{0, 0, 0, 0}
};

enum sctp_param_flags {
	ORIG_SPORT_BIT = 0,
	ORIG_SPORT = (1 << ORIG_SPORT_BIT),

	ORIG_DPORT_BIT = 1,
	ORIG_DPORT = (1 << ORIG_DPORT_BIT),

	REPL_SPORT_BIT = 2,
	REPL_SPORT = (1 << REPL_SPORT_BIT),

	REPL_DPORT_BIT = 3,
	REPL_DPORT = (1 << REPL_DPORT_BIT),

	STATE_BIT = 4,
	STATE = (1 << STATE_BIT)
};

static const char *states[] = {
	"NONE",
	"CLOSED",
	"COOKIE_WAIT",
	"COOKIE_ECHOED",
	"ESTABLISHED",
	"SHUTDOWN_SENT",
	"SHUTDOWN_RECV",
	"SHUTDOWN_ACK_SENT",
};

void help()
{
	fprintf(stdout, "--orig-port-src        original source port\n");
	fprintf(stdout, "--orig-port-dst        original destination port\n");
	fprintf(stdout, "--reply-port-src       reply source port\n");
	fprintf(stdout, "--reply-port-dst       reply destination port\n");
	fprintf(stdout, "--state                SCTP state, fe. ESTABLISHED\n");
}

int parse_options(char c, char *argv[], 
		  struct nfct_tuple *orig,
		  struct nfct_tuple *reply,
		  struct nfct_tuple *mask,
		  union nfct_protoinfo *proto,
		  unsigned int *flags)
{
	switch(c) {
		case '1':
			if (optarg) {
				orig->l4src.sctp.port = htons(atoi(optarg));
				*flags |= ORIG_SPORT;
			}
			break;
		case '2':
			if (optarg) {
				orig->l4dst.sctp.port = htons(atoi(optarg));
				*flags |= ORIG_DPORT;
			}
			break;
		case '3':
			if (optarg) {
				reply->l4src.sctp.port = htons(atoi(optarg));
				*flags |= REPL_SPORT;
			}
			break;
		case '4':
			if (optarg) {
				reply->l4dst.sctp.port = htons(atoi(optarg));
				*flags |= REPL_DPORT;
			}
			break;
		case '5':
			if (optarg) {
				int i;
				for (i=0; i<10; i++) {
					if (strcmp(optarg, states[i]) == 0) {
						/* FIXME: Add state to
						 * nfct_protoinfo
						proto->sctp.state = i; */
						break;
					}
				}
				if (i == 10) {
					printf("doh?\n");
					return 0;
				}
			}
			break;
	}
	return 1;
}

int final_check(unsigned int flags,
		struct nfct_tuple *orig,
		struct nfct_tuple *reply)
{
	if ((flags & (ORIG_SPORT|ORIG_DPORT)) 
	    && !(flags & (REPL_SPORT|REPL_DPORT))) {
		reply->l4src.sctp.port = orig->l4dst.sctp.port;
		reply->l4dst.sctp.port = orig->l4src.sctp.port;
		return 1;
	} else if (!(flags & (ORIG_SPORT|ORIG_DPORT))
	            && (flags & (REPL_SPORT|REPL_DPORT))) {
		orig->l4src.sctp.port = reply->l4dst.sctp.port;
		orig->l4dst.sctp.port = reply->l4src.sctp.port;
		return 1;
	}
	if ((flags & (ORIG_SPORT|ORIG_DPORT)) 
	    && ((flags & (REPL_SPORT|REPL_DPORT))))
		return 1;

	return 0;
}

static struct ctproto_handler sctp = {
	.name 			= "sctp",
	.protonum		= IPPROTO_SCTP,
	.parse_opts		= parse_options,
	.final_check		= final_check,
	.help			= help,
	.opts			= opts,
	.version		= LIBCT_VERSION,
};

void __attribute__ ((constructor)) init(void);
void __attribute__ ((destructor)) fini(void);

void init(void)
{
	register_proto(&sctp);
}

void fini(void)
{
	unregister_proto(&sctp);
}