summaryrefslogtreecommitdiffstats
path: root/src/nfct.c
blob: 533d75d3133bdbd635193d79a965268388f2f1e5 (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
180
181
182
183
184
185
186
187
188
189
190
191
/*
 * (C) 2012 by Pablo Neira Ayuso <pablo@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.
 *
 * This code has been sponsored by Vyatta Inc. <http://www.vyatta.com>
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <time.h>
#include <netinet/in.h>
#include <errno.h>

#include <libmnl/libmnl.h>

#include "linux_list.h"
#include "nfct.h"

static int nfct_cmd_version(int argc, char *argv[]);
static int nfct_cmd_help(int argc, char *argv[]);

static void usage(char *argv[])
{
	fprintf(stderr, "Usage: %s subsystem command [parameters]...\n",
		argv[0]);
}

void nfct_perror(const char *msg)
{
	if (errno == 0) {
		fprintf(stderr, "nfct v%s: %s\n", VERSION, msg);
	} else {
		fprintf(stderr, "nfct v%s: %s: %s\n",
			VERSION, msg, strerror(errno));
	}
}

static LIST_HEAD(nfct_extension_list);

void nfct_extension_register(struct nfct_extension *ext)
{
	list_add(&ext->head, &nfct_extension_list);
}

static struct nfct_extension *nfct_extension_lookup(int type)
{
	struct nfct_extension *ext;

	list_for_each_entry(ext, &nfct_extension_list, head) {
		if (ext->type == type)
			return ext;
	}
	return NULL;
}

int main(int argc, char *argv[])
{
	int subsys = NFCT_SUBSYS_NONE, ret = 0;
	struct nfct_extension *ext;
	struct mnl_socket *nl;

	if (argc < 2) {
		usage(argv);
		exit(EXIT_FAILURE);
	}
	if (strncmp(argv[1], "timeout", strlen(argv[1])) == 0) {
		subsys = NFCT_SUBSYS_TIMEOUT;
	} else if (strncmp(argv[1], "helper", strlen(argv[1])) == 0) {
		subsys = NFCT_SUBSYS_HELPER;
	} else if (strncmp(argv[1], "version", strlen(argv[1])) == 0)
		subsys = NFCT_SUBSYS_VERSION;
	else if (strncmp(argv[1], "help", strlen(argv[1])) == 0)
		subsys = NFCT_SUBSYS_HELP;
	else {
		fprintf(stderr, "nfct v%s: Unknown subsystem: %s\n",
			VERSION, argv[1]);
		usage(argv);
		exit(EXIT_FAILURE);
	}

	switch(subsys) {
	case NFCT_SUBSYS_VERSION:
		ret = nfct_cmd_version(argc, argv);
		break;
	case NFCT_SUBSYS_HELP:
		ret = nfct_cmd_help(argc, argv);
		break;
	default:
		ext = nfct_extension_lookup(subsys);
		if (ext == NULL) {
			fprintf(stderr, "nfct v%s: subsystem %s not supported\n",
				VERSION, argv[1]);
			return EXIT_FAILURE;
		}

		nl = nfct_mnl_open();
		if (nl == NULL) {
			nfct_perror("cannot open netlink");
			return -1;
		}

		ret = ext->parse_params(nl, argc, argv);
		mnl_socket_close(nl);
		break;
	}
	return ret < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}

static const char version_msg[] =
	"nfct v%s: utility for the Netfilter's Connection Tracking System\n"
	"Copyright (C) 2012 Pablo Neira Ayuso <pablo@netfilter.org>\n"
	"This program comes with ABSOLUTELY NO WARRANTY.\n"
	"This is free software, and you are welcome to redistribute it under "
	"certain \nconditions; see LICENSE file distributed in this package "
	"for details.\n";

static int nfct_cmd_version(int argc, char *argv[])
{
	printf(version_msg, VERSION);
	return 0;
}

static const char help_msg[] =
	"nfct v%s: utility for the Netfilter's Connection Tracking System\n"
	"Usage: %s command [parameters]...\n\n"
	"Subsystem:\n"
	"  helper\t\tAllows to configure user-space helper\n"
	"  timeout\t\tAllows definition of fine-grain timeout policies\n"
	"  version\t\tDisplay version and disclaimer\n"
	"  help\t\t\tDisplay this help message\n"
	"Commands:\n"
	"  list [reset]\t\tList the accounting object table (and reset)\n"
	"  add object-name\tAdd new accounting object to table\n"
	"  delete object-name\tDelete existing accounting object\n"
	"  get object-name\tGet existing accounting object\n"
	"  flush\t\t\tFlush accounting object table\n";

static int nfct_cmd_help(int argc, char *argv[])
{
	printf(help_msg, VERSION, argv[0]);
	return 0;
}

int nfct_mnl_talk(struct mnl_socket *nl, struct nlmsghdr *nlh,
		  uint32_t seq, uint32_t portid,
		  int (*cb)(const struct nlmsghdr *nlh, void *data),
		  void *data)
{
	int ret;
	char buf[MNL_SOCKET_BUFFER_SIZE];

	if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0)
		return -1;

	ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
	while (ret > 0) {
		ret = mnl_cb_run(buf, ret, seq, portid, cb, data);
		if (ret <= 0)
			break;

		ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
	}
	if (ret == -1)
		return -1;

	return 0;
}

struct mnl_socket *nfct_mnl_open(void)
{
	struct mnl_socket *nl;

	nl = mnl_socket_open(NETLINK_NETFILTER);
	if (nl == NULL)
		return NULL;

	if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0)
		return NULL;

	return nl;
}