summaryrefslogtreecommitdiffstats
path: root/iptables/xtables-save.c
blob: 5a82cac5dd7c0158fa9dd2a690c046d422d5d4a3 (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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
/* Code to save the xtables state, in human readable-form. */
/* (C) 1999 by Paul 'Rusty' Russell <rusty@rustcorp.com.au> and
 * (C) 2000-2002 by Harald Welte <laforge@gnumonks.org>
 * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * This code is distributed under the terms of GNU GPL v2
 *
 */
#include "config.h"
#include <getopt.h>
#include <errno.h>
#include <libgen.h>
#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <netdb.h>
#include <unistd.h>
#include "libiptc/libiptc.h"
#include "iptables.h"
#include "xtables-multi.h"
#include "nft.h"
#include "nft-cache.h"

#include <libnftnl/chain.h>

#ifndef NO_SHARED_LIBS
#include <dlfcn.h>
#endif

#define prog_name xtables_globals.program_name
#define prog_vers xtables_globals.program_version

static const char *ipt_save_optstring = "bcdt:M:f:V";
static const struct option ipt_save_options[] = {
	{.name = "counters", .has_arg = false, .val = 'c'},
	{.name = "version",  .has_arg = false, .val = 'V'},
	{.name = "dump",     .has_arg = false, .val = 'd'},
	{.name = "table",    .has_arg = true,  .val = 't'},
	{.name = "modprobe", .has_arg = true,  .val = 'M'},
	{.name = "file",     .has_arg = true,  .val = 'f'},
	{NULL},
};

static const char *arp_save_optstring = "cM:V";
static const struct option arp_save_options[] = {
	{.name = "counters", .has_arg = false, .val = 'c'},
	{.name = "version",  .has_arg = false, .val = 'V'},
	{.name = "modprobe", .has_arg = true,  .val = 'M'},
	{NULL},
};

static const char *ebt_save_optstring = "ct:M:V";
static const struct option ebt_save_options[] = {
	{.name = "counters", .has_arg = false, .val = 'c'},
	{.name = "version",  .has_arg = false, .val = 'V'},
	{.name = "table",    .has_arg = true,  .val = 't'},
	{.name = "modprobe", .has_arg = true,  .val = 'M'},
	{NULL},
};

struct do_output_data {
	unsigned int format;
	bool commit;
};

static int
__do_output(struct nft_handle *h, const char *tablename, void *data)
{
	struct do_output_data *d = data;
	time_t now;

	if (!nft_table_builtin_find(h, tablename))
		return 0;

	if (!nft_is_table_compatible(h, tablename, NULL)) {
		printf("# Table `%s' is incompatible, use 'nft' tool.\n",
		       tablename);
		return 0;
	} else if (nft_is_table_tainted(h, tablename)) {
		printf("# Table `%s' contains incompatible base-chains, use 'nft' tool to list them.\n",
		       tablename);
	}

	now = time(NULL);
	printf("# Generated by %s v%s on %s", prog_name,
	       prog_vers, ctime(&now));

	printf("*%s\n", tablename);
	/* Dump out chain names first,
	 * thereby preventing dependency conflicts */
	nft_cache_sort_chains(h, tablename);
	nft_chain_foreach(h, tablename, nft_chain_save, h);
	nft_rule_save(h, tablename, d->format);
	if (d->commit)
		printf("COMMIT\n");

	now = time(NULL);
	printf("# Completed on %s", ctime(&now));
	return 0;
}

static int
do_output(struct nft_handle *h, const char *tablename, struct do_output_data *d)
{
	int ret;

	if (!tablename) {
		ret = nft_for_each_table(h, __do_output, d);
		nft_check_xt_legacy(h->family, true);
		return !!ret;
	}

	if (!nft_table_find(h, tablename) &&
	    !nft_table_builtin_find(h, tablename)) {
		fprintf(stderr, "Table `%s' does not exist\n", tablename);
		return 1;
	}

	ret = __do_output(h, tablename, d);
	nft_check_xt_legacy(h->family, true);
	return ret;
}

/* Format:
 * :Chain name POLICY packets bytes
 * rule
 */
static int
xtables_save_main(int family, int argc, char *argv[],
		  const char *optstring, const struct option *longopts)
{
	const char *tablename = NULL;
	struct do_output_data d = {
		.format = FMT_NOCOUNTS,
	};
	struct nft_handle h;
	bool dump = false;
	FILE *file = NULL;
	int ret, c;

	xtables_globals.program_name = basename(*argv);;
	c = xtables_init_all(&xtables_globals, family);
	if (c < 0) {
		fprintf(stderr, "%s/%s Failed to initialize xtables\n",
				xtables_globals.program_name,
				xtables_globals.program_version);
		exit(1);
	}

	while ((c = getopt_long(argc, argv, optstring, longopts, NULL)) != -1) {
		switch (c) {
		case 'b':
			fprintf(stderr, "-b/--binary option is not implemented\n");
			break;
		case 'c':
			d.format &= ~FMT_NOCOUNTS;
			break;

		case 't':
			/* Select specific table. */
			tablename = optarg;
			break;
		case 'M':
			xtables_modprobe_program = optarg;
			break;
		case 'f':
			file = fopen(optarg, "w");
			if (file == NULL) {
				fprintf(stderr, "Failed to open file, error: %s\n",
					strerror(errno));
				exit(1);
			}
			ret = dup2(fileno(file), STDOUT_FILENO);
			if (ret == -1) {
				fprintf(stderr, "Failed to redirect stdout, error: %s\n",
					strerror(errno));
				exit(1);
			}
			fclose(file);
			break;
		case 'd':
			dump = true;
			break;
		case 'V':
			printf("%s v%s\n", prog_name, prog_vers);
			exit(0);
		default:
			fprintf(stderr,
				"Look at manual page `%s.8' for more information.\n",
				prog_name);
			exit(1);
		}
	}

	if (optind < argc) {
		fprintf(stderr, "Unknown arguments found on commandline\n");
		exit(1);
	}

	init_extensions();
	switch (family) {
	case NFPROTO_IPV4:
		init_extensions4();
		d.commit = true;
		break;
	case NFPROTO_IPV6:
		init_extensions6();
		d.commit = true;
		break;
	case NFPROTO_ARP:
		init_extensionsa();
		break;
	case NFPROTO_BRIDGE: {
		const char *ctr = getenv("EBTABLES_SAVE_COUNTER");

		if (!(d.format & FMT_NOCOUNTS)) {
			d.format |= FMT_EBT_SAVE;
		} else if (ctr && !strcmp(ctr, "yes")) {
			d.format &= ~FMT_NOCOUNTS;
			d.format |= FMT_C_COUNTS | FMT_EBT_SAVE;
		}
		init_extensionsb();
		break;
	}
	default:
		fprintf(stderr, "Unknown family %d\n", family);
		return 1;
	}

	if (nft_init(&h, family) < 0) {
		fprintf(stderr, "%s/%s Failed to initialize nft: %s\n",
				xtables_globals.program_name,
				xtables_globals.program_version,
				strerror(errno));
		exit(EXIT_FAILURE);
	}

	nft_cache_level_set(&h, NFT_CL_RULES, NULL);
	nft_cache_build(&h);
	nft_xt_fake_builtin_chains(&h, tablename, NULL);

	ret = do_output(&h, tablename, &d);
	nft_fini(&h);
	xtables_fini();
	if (dump)
		exit(0);

	return ret;
}

int xtables_ip4_save_main(int argc, char *argv[])
{
	return xtables_save_main(NFPROTO_IPV4, argc, argv,
				 ipt_save_optstring, ipt_save_options);
}

int xtables_ip6_save_main(int argc, char *argv[])
{
	return xtables_save_main(NFPROTO_IPV6, argc, argv,
				 ipt_save_optstring, ipt_save_options);
}

int xtables_eb_save_main(int argc, char *argv[])
{
	return xtables_save_main(NFPROTO_BRIDGE, argc, argv,
				 ebt_save_optstring, ebt_save_options);
}

int xtables_arp_save_main(int argc, char *argv[])
{
	return xtables_save_main(NFPROTO_ARP, argc, argv,
				 arp_save_optstring, arp_save_options);
}