summaryrefslogtreecommitdiffstats
path: root/src/libnftables.c
blob: dc6a5fdf3264032af9172a93181a9982faf64c0f (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
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
/*
 * Copyright (c) 2017 Eric Leblond <eric@regit.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <nftables/nftables.h>
#include <erec.h>
#include <mnl.h>
#include <parser.h>
#include <utils.h>
#include <iface.h>

#include <errno.h>
#include <stdlib.h>
#include <string.h>

static int nft_netlink(struct nft_ctx *nft,
		       struct parser_state *state, struct list_head *msgs,
		       struct mnl_socket *nf_sock)
{
	uint32_t batch_seqnum, seqnum = 0;
	struct nftnl_batch *batch;
	struct netlink_ctx ctx;
	struct cmd *cmd;
	struct mnl_err *err, *tmp;
	LIST_HEAD(err_list);
	bool batch_supported = netlink_batch_supported(nf_sock, &seqnum);
	int ret = 0;

	batch = mnl_batch_init();

	batch_seqnum = mnl_batch_begin(batch, mnl_seqnum_alloc(&seqnum));
	list_for_each_entry(cmd, &state->cmds, list) {
		memset(&ctx, 0, sizeof(ctx));
		ctx.msgs = msgs;
		ctx.seqnum = cmd->seqnum = mnl_seqnum_alloc(&seqnum);
		ctx.batch = batch;
		ctx.batch_supported = batch_supported;
		ctx.octx = &nft->output;
		ctx.nf_sock = nf_sock;
		ctx.cache = &nft->cache;
		ctx.debug_mask = nft->debug_mask;
		init_list_head(&ctx.list);
		ret = do_command(&ctx, cmd);
		if (ret < 0)
			goto out;
	}
	if (!nft->check)
		mnl_batch_end(batch, mnl_seqnum_alloc(&seqnum));

	if (!mnl_batch_ready(batch))
		goto out;

	ret = netlink_batch_send(&ctx, &err_list);

	list_for_each_entry_safe(err, tmp, &err_list, head) {
		list_for_each_entry(cmd, &state->cmds, list) {
			if (err->seqnum == cmd->seqnum ||
			    err->seqnum == batch_seqnum) {
				netlink_io_error(&ctx, &cmd->location,
						 "Could not process rule: %s",
						 strerror(err->err));
				errno = err->err;
				if (err->seqnum == cmd->seqnum) {
					mnl_err_list_free(err);
					break;
				}
			}
		}
	}
out:
	mnl_batch_reset(batch);
	return ret;
}

static int nft_run(struct nft_ctx *nft, struct mnl_socket *nf_sock,
		   void *scanner, struct parser_state *state,
		   struct list_head *msgs)
{
	struct cmd *cmd, *next;
	int ret;

	ret = nft_parse(nft, scanner, state);
	if (ret != 0 || state->nerrs > 0) {
		ret = -1;
		goto err1;
	}

	list_for_each_entry(cmd, &state->cmds, list)
		nft_cmd_expand(cmd);

	ret = nft_netlink(nft, state, msgs, nf_sock);
err1:
	list_for_each_entry_safe(cmd, next, &state->cmds, list) {
		list_del(&cmd->list);
		cmd_free(cmd);
	}

	return ret;
}

static void nft_init(void)
{
	mark_table_init();
	realm_table_rt_init();
	devgroup_table_init();
	realm_table_meta_init();
	ct_label_table_init();
	gmp_init();
#ifdef HAVE_LIBXTABLES
	xt_init();
#endif
}

static void nft_exit(void)
{
	ct_label_table_exit();
	realm_table_rt_exit();
	devgroup_table_exit();
	realm_table_meta_exit();
	mark_table_exit();
}

int nft_ctx_add_include_path(struct nft_ctx *ctx, const char *path)
{
	char **tmp;
	int pcount = ctx->num_include_paths;

	tmp = realloc(ctx->include_paths, (pcount + 1) * sizeof(char *));
	if (!tmp)
		return -1;

	ctx->include_paths = tmp;

	if (asprintf(&ctx->include_paths[pcount], "%s", path) < 0)
		return -1;

	ctx->num_include_paths++;
	return 0;
}

void nft_ctx_clear_include_paths(struct nft_ctx *ctx)
{
	while (ctx->num_include_paths)
		xfree(ctx->include_paths[--ctx->num_include_paths]);

	xfree(ctx->include_paths);
	ctx->include_paths = NULL;
}

static void nft_ctx_netlink_init(struct nft_ctx *ctx)
{
	ctx->nf_sock = netlink_open_sock();
}

struct nft_ctx *nft_ctx_new(uint32_t flags)
{
	struct nft_ctx *ctx;

	nft_init();
	ctx = xzalloc(sizeof(struct nft_ctx));

	nft_ctx_add_include_path(ctx, DEFAULT_INCLUDE_PATH);
	ctx->parser_max_errors	= 10;
	init_list_head(&ctx->cache.list);
	ctx->flags = flags;

	if (flags == NFT_CTX_DEFAULT)
		nft_ctx_netlink_init(ctx);

	return ctx;
}

void nft_ctx_free(struct nft_ctx *ctx)
{
	if (ctx->nf_sock)
		netlink_close_sock(ctx->nf_sock);

	iface_cache_release();
	cache_release(&ctx->cache);
	nft_ctx_clear_include_paths(ctx);
	xfree(ctx);
	nft_exit();
}

FILE *nft_ctx_set_output(struct nft_ctx *ctx, FILE *fp)
{
	FILE *old = ctx->output.output_fp;

	ctx->output.output_fp = fp;

	return old;
}

bool nft_ctx_get_dry_run(struct nft_ctx *ctx)
{
	return ctx->check;
}

void nft_ctx_set_dry_run(struct nft_ctx *ctx, bool dry)
{
	ctx->check = dry;
}

enum nft_numeric_level nft_ctx_output_get_numeric(struct nft_ctx *ctx)
{
	return ctx->output.numeric;
}

void nft_ctx_output_set_numeric(struct nft_ctx *ctx,
				enum nft_numeric_level level)
{
	ctx->output.numeric = level;
}

bool nft_ctx_output_get_stateless(struct nft_ctx *ctx)
{
	return ctx->output.stateless;
}

void nft_ctx_output_set_stateless(struct nft_ctx *ctx, bool val)
{
	ctx->output.stateless = val;
}

bool nft_ctx_output_get_ip2name(struct nft_ctx *ctx)
{
	return ctx->output.ip2name;
}

void nft_ctx_output_set_ip2name(struct nft_ctx *ctx, bool val)
{
	ctx->output.ip2name = val;
}

unsigned int nft_ctx_output_get_debug(struct nft_ctx *ctx)
{
	return ctx->debug_mask;
}
void nft_ctx_output_set_debug(struct nft_ctx *ctx, unsigned int mask)
{
	ctx->debug_mask = mask;
}

bool nft_ctx_output_get_handle(struct nft_ctx *ctx)
{
	return ctx->output.handle;
}

void nft_ctx_output_set_handle(struct nft_ctx *ctx, bool val)
{
	ctx->output.handle = val;
}

bool nft_ctx_output_get_echo(struct nft_ctx *ctx)
{
	return ctx->output.echo;
}

void nft_ctx_output_set_echo(struct nft_ctx *ctx, bool val)
{
	ctx->output.echo = val;
}

static const struct input_descriptor indesc_cmdline = {
	.type	= INDESC_BUFFER,
	.name	= "<cmdline>",
};

int nft_run_cmd_from_buffer(struct nft_ctx *nft, char *buf, size_t buflen)
{
	int rc = NFT_EXIT_SUCCESS;
	struct parser_state state;
	LIST_HEAD(msgs);
	void *scanner;
	FILE *fp;

	parser_init(nft->nf_sock, &nft->cache, &state,
		    &msgs, nft->debug_mask, &nft->output);
	scanner = scanner_init(&state);
	scanner_push_buffer(scanner, &indesc_cmdline, buf);

	if (nft_run(nft, nft->nf_sock, scanner, &state, &msgs) != 0)
		rc = NFT_EXIT_FAILURE;

	fp = nft_ctx_set_output(nft, stderr);
	erec_print_list(&nft->output, &msgs, nft->debug_mask);
	nft_ctx_set_output(nft, fp);
	scanner_destroy(scanner);
	iface_cache_release();

	return rc;
}

int nft_run_cmd_from_filename(struct nft_ctx *nft, const char *filename)
{
	struct parser_state state;
	LIST_HEAD(msgs);
	void *scanner;
	int rc;
	FILE *fp;

	rc = cache_update(nft->nf_sock, &nft->cache, CMD_INVALID, &msgs,
			  nft->debug_mask, &nft->output);
	if (rc < 0)
		return NFT_EXIT_FAILURE;

	parser_init(nft->nf_sock, &nft->cache, &state,
		    &msgs, nft->debug_mask, &nft->output);
	scanner = scanner_init(&state);
	if (scanner_read_file(scanner, filename, &internal_location) < 0) {
		rc = NFT_EXIT_FAILURE;
		goto err;
	}

	if (nft_run(nft, nft->nf_sock, scanner, &state, &msgs) != 0)
		rc = NFT_EXIT_FAILURE;
err:
	fp = nft_ctx_set_output(nft, stderr);
	erec_print_list(&nft->output, &msgs, nft->debug_mask);
	nft_ctx_set_output(nft, fp);
	scanner_destroy(scanner);
	iface_cache_release();

	return rc;
}

int nft_print(struct output_ctx *octx, const char *fmt, ...)
{
	int ret;
	va_list arg;

	if (!octx->output_fp)
		return -1;

	va_start(arg, fmt);
	ret = vfprintf(octx->output_fp, fmt, arg);
	va_end(arg);
	fflush(octx->output_fp);

	return ret;
}

int nft_gmp_print(struct output_ctx *octx, const char *fmt, ...)
{
	int ret;
	va_list arg;

	if (!octx->output_fp)
		return -1;

	va_start(arg, fmt);
	ret = gmp_vfprintf(octx->output_fp, fmt, arg);
	va_end(arg);
	fflush(octx->output_fp);

	return ret;
}