xref: /freebsd/sbin/ipfw/nat64clat.c (revision 2e3f49888ec8851bafb22011533217487764fdb0) 
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Yandex LLC
5  * Copyright (c) 2019 Andrey V. Elsukov <ae@FreeBSD.org>
6  * Copyright (c) 2019 Boris N. Lytochkin <lytboris@gmail.com>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 
33 #include "ipfw2.h"
34 
35 #include <ctype.h>
36 #include <err.h>
37 #include <errno.h>
38 #include <inttypes.h>
39 #include <netdb.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <sysexits.h>
44 
45 #include <net/if.h>
46 #include <netinet/in.h>
47 #include <netinet/ip_fw.h>
48 #include <netinet6/ip_fw_nat64.h>
49 #include <arpa/inet.h>
50 
51 typedef int (nat64clat_cb_t)(ipfw_nat64clat_cfg *i, const char *name,
52     uint8_t set);
53 static int nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set,
54     int sort);
55 
56 static void nat64clat_create(const char *name, uint8_t set, int ac, char **av);
57 static void nat64clat_config(const char *name, uint8_t set, int ac, char **av);
58 static void nat64clat_destroy(const char *name, uint8_t set);
59 static void nat64clat_stats(const char *name, uint8_t set);
60 static void nat64clat_reset_stats(const char *name, uint8_t set);
61 static int nat64clat_show_cb(ipfw_nat64clat_cfg *cfg, const char *name,
62     uint8_t set);
63 static int nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name,
64     uint8_t set);
65 
66 static struct _s_x nat64cmds[] = {
67       { "create",	TOK_CREATE },
68       { "config",	TOK_CONFIG },
69       { "destroy",	TOK_DESTROY },
70       { "list",		TOK_LIST },
71       { "show",		TOK_LIST },
72       { "stats",	TOK_STATS },
73       { NULL, 0 }
74 };
75 
76 static struct _s_x nat64statscmds[] = {
77       { "reset",	TOK_RESET },
78       { NULL, 0 }
79 };
80 
81 /*
82  * This one handles all nat64clat-related commands
83  *	ipfw [set N] nat64clat NAME {create | config} ...
84  *	ipfw [set N] nat64clat NAME stats [reset]
85  *	ipfw [set N] nat64clat {NAME | all} destroy
86  *	ipfw [set N] nat64clat {NAME | all} {list | show}
87  */
88 #define	nat64clat_check_name	table_check_name
89 void
90 ipfw_nat64clat_handler(int ac, char *av[])
91 {
92 	const char *name;
93 	int tcmd;
94 	uint8_t set;
95 
96 	if (g_co.use_set != 0)
97 		set = g_co.use_set - 1;
98 	else
99 		set = 0;
100 	ac--; av++;
101 
102 	NEED1("nat64clat needs instance name");
103 	name = *av;
104 	if (nat64clat_check_name(name) != 0) {
105 		if (strcmp(name, "all") == 0)
106 			name = NULL;
107 		else
108 			errx(EX_USAGE, "nat64clat instance name %s is invalid",
109 			    name);
110 	}
111 	ac--; av++;
112 	NEED1("nat64clat needs command");
113 
114 	tcmd = get_token(nat64cmds, *av, "nat64clat command");
115 	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
116 		errx(EX_USAGE, "nat64clat instance name required");
117 	switch (tcmd) {
118 	case TOK_CREATE:
119 		ac--; av++;
120 		nat64clat_create(name, set, ac, av);
121 		break;
122 	case TOK_CONFIG:
123 		ac--; av++;
124 		nat64clat_config(name, set, ac, av);
125 		break;
126 	case TOK_LIST:
127 		nat64clat_foreach(nat64clat_show_cb, name, set, 1);
128 		break;
129 	case TOK_DESTROY:
130 		if (name == NULL)
131 			nat64clat_foreach(nat64clat_destroy_cb, NULL, set, 0);
132 		else
133 			nat64clat_destroy(name, set);
134 		break;
135 	case TOK_STATS:
136 		ac--; av++;
137 		if (ac == 0) {
138 			nat64clat_stats(name, set);
139 			break;
140 		}
141 		tcmd = get_token(nat64statscmds, *av, "stats command");
142 		if (tcmd == TOK_RESET)
143 			nat64clat_reset_stats(name, set);
144 	}
145 }
146 
147 
148 static void
149 nat64clat_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
150 {
151 
152 	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
153 	ntlv->head.length = sizeof(ipfw_obj_ntlv);
154 	ntlv->idx = 1;
155 	ntlv->set = set;
156 	strlcpy(ntlv->name, name, sizeof(ntlv->name));
157 }
158 
159 static struct _s_x nat64newcmds[] = {
160       { "plat_prefix",	TOK_PLAT_PREFIX },
161       { "clat_prefix",	TOK_CLAT_PREFIX },
162       { "log",		TOK_LOG },
163       { "-log",		TOK_LOGOFF },
164       { "allow_private", TOK_PRIVATE },
165       { "-allow_private", TOK_PRIVATEOFF },
166       { NULL, 0 }
167 };
168 
169 /*
170  * Creates new nat64clat instance
171  * ipfw nat64clat <NAME> create clat_prefix <prefix> plat_prefix <prefix>
172  * Request: [ ipfw_obj_lheader ipfw_nat64clat_cfg ]
173  */
174 #define	NAT64CLAT_HAS_CLAT_PREFIX	0x01
175 #define	NAT64CLAT_HAS_PLAT_PREFIX	0x02
176 static void
177 nat64clat_create(const char *name, uint8_t set, int ac, char *av[])
178 {
179 	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nat64clat_cfg)];
180 	ipfw_nat64clat_cfg *cfg;
181 	ipfw_obj_lheader *olh;
182 	int tcmd, flags;
183 	char *p;
184 	struct in6_addr prefix;
185 	uint8_t plen;
186 
187 	memset(buf, 0, sizeof(buf));
188 	olh = (ipfw_obj_lheader *)buf;
189 	cfg = (ipfw_nat64clat_cfg *)(olh + 1);
190 
191 	/* Some reasonable defaults */
192 	inet_pton(AF_INET6, "64:ff9b::", &cfg->plat_prefix);
193 	cfg->plat_plen = 96;
194 	cfg->set = set;
195 	flags = NAT64CLAT_HAS_PLAT_PREFIX;
196 	while (ac > 0) {
197 		tcmd = get_token(nat64newcmds, *av, "option");
198 		ac--; av++;
199 
200 		switch (tcmd) {
201 		case TOK_PLAT_PREFIX:
202 		case TOK_CLAT_PREFIX:
203 			if (tcmd == TOK_PLAT_PREFIX) {
204 				NEED1("IPv6 plat_prefix required");
205 			} else {
206 				NEED1("IPv6 clat_prefix required");
207 			}
208 
209 			if ((p = strchr(*av, '/')) != NULL)
210 				*p++ = '\0';
211 			if (inet_pton(AF_INET6, *av, &prefix) != 1)
212 				errx(EX_USAGE,
213 				    "Bad prefix: %s", *av);
214 			plen = strtol(p, NULL, 10);
215 			if (ipfw_check_nat64prefix(&prefix, plen) != 0)
216 				errx(EX_USAGE,
217 				    "Bad prefix length: %s", p);
218 			if (tcmd == TOK_PLAT_PREFIX) {
219 				flags |= NAT64CLAT_HAS_PLAT_PREFIX;
220 				cfg->plat_prefix = prefix;
221 				cfg->plat_plen = plen;
222 			} else {
223 				flags |= NAT64CLAT_HAS_CLAT_PREFIX;
224 				cfg->clat_prefix = prefix;
225 				cfg->clat_plen = plen;
226 			}
227 			ac--; av++;
228 			break;
229 		case TOK_LOG:
230 			cfg->flags |= NAT64_LOG;
231 			break;
232 		case TOK_LOGOFF:
233 			cfg->flags &= ~NAT64_LOG;
234 			break;
235 		case TOK_PRIVATE:
236 			cfg->flags |= NAT64_ALLOW_PRIVATE;
237 			break;
238 		case TOK_PRIVATEOFF:
239 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
240 			break;
241 		}
242 	}
243 
244 	/* Check validness */
245 	if ((flags & NAT64CLAT_HAS_PLAT_PREFIX) != NAT64CLAT_HAS_PLAT_PREFIX)
246 		errx(EX_USAGE, "plat_prefix required");
247 	if ((flags & NAT64CLAT_HAS_CLAT_PREFIX) != NAT64CLAT_HAS_CLAT_PREFIX)
248 		errx(EX_USAGE, "clat_prefix required");
249 
250 	olh->count = 1;
251 	olh->objsize = sizeof(*cfg);
252 	olh->size = sizeof(buf);
253 	strlcpy(cfg->name, name, sizeof(cfg->name));
254 	if (do_set3(IP_FW_NAT64CLAT_CREATE, &olh->opheader, sizeof(buf)) != 0)
255 		err(EX_OSERR, "nat64clat instance creation failed");
256 }
257 
258 /*
259  * Configures existing nat64clat instance
260  * ipfw nat64clat <NAME> config <options>
261  * Request: [ ipfw_obj_header ipfw_nat64clat_cfg ]
262  */
263 static void
264 nat64clat_config(const char *name, uint8_t set, int ac, char **av)
265 {
266 	char buf[sizeof(ipfw_obj_header) + sizeof(ipfw_nat64clat_cfg)];
267 	ipfw_nat64clat_cfg *cfg;
268 	ipfw_obj_header *oh;
269 	char *opt;
270 	char *p;
271 	size_t sz;
272 	int tcmd;
273 	struct in6_addr prefix;
274 	uint8_t plen;
275 
276 	if (ac == 0)
277 		errx(EX_USAGE, "config options required");
278 	memset(&buf, 0, sizeof(buf));
279 	oh = (ipfw_obj_header *)buf;
280 	cfg = (ipfw_nat64clat_cfg *)(oh + 1);
281 	sz = sizeof(buf);
282 
283 	nat64clat_fill_ntlv(&oh->ntlv, name, set);
284 	if (do_get3(IP_FW_NAT64CLAT_CONFIG, &oh->opheader, &sz) != 0)
285 		err(EX_OSERR, "failed to get config for instance %s", name);
286 
287 	while (ac > 0) {
288 		tcmd = get_token(nat64newcmds, *av, "option");
289 		opt = *av;
290 		ac--; av++;
291 
292 		switch (tcmd) {
293 		case TOK_PLAT_PREFIX:
294 		case TOK_CLAT_PREFIX:
295 			if (tcmd == TOK_PLAT_PREFIX) {
296 				NEED1("IPv6 plat_prefix required");
297 			} else {
298 				NEED1("IPv6 clat_prefix required");
299 			}
300 
301 			if ((p = strchr(*av, '/')) != NULL)
302 				*p++ = '\0';
303 			else
304 				errx(EX_USAGE,
305 				    "Prefix length required: %s", *av);
306 			if (inet_pton(AF_INET6, *av, &prefix) != 1)
307 				errx(EX_USAGE,
308 				    "Bad prefix: %s", *av);
309 			plen = strtol(p, NULL, 10);
310 			if (ipfw_check_nat64prefix(&prefix, plen) != 0)
311 				errx(EX_USAGE,
312 				    "Bad prefix length: %s", p);
313 			if (tcmd == TOK_PLAT_PREFIX) {
314 				cfg->plat_prefix = prefix;
315 				cfg->plat_plen = plen;
316 			} else {
317 				cfg->clat_prefix = prefix;
318 				cfg->clat_plen = plen;
319 			}
320 			ac--; av++;
321 			break;
322 		case TOK_LOG:
323 			cfg->flags |= NAT64_LOG;
324 			break;
325 		case TOK_LOGOFF:
326 			cfg->flags &= ~NAT64_LOG;
327 			break;
328 		case TOK_PRIVATE:
329 			cfg->flags |= NAT64_ALLOW_PRIVATE;
330 			break;
331 		case TOK_PRIVATEOFF:
332 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
333 			break;
334 		default:
335 			errx(EX_USAGE, "Can't change %s option", opt);
336 		}
337 	}
338 
339 	if (do_set3(IP_FW_NAT64CLAT_CONFIG, &oh->opheader, sizeof(buf)) != 0)
340 		err(EX_OSERR, "nat64clat instance configuration failed");
341 }
342 
343 /*
344  * Destroys nat64clat instance.
345  * Request: [ ipfw_obj_header ]
346  */
347 static void
348 nat64clat_destroy(const char *name, uint8_t set)
349 {
350 	ipfw_obj_header oh;
351 
352 	memset(&oh, 0, sizeof(oh));
353 	nat64clat_fill_ntlv(&oh.ntlv, name, set);
354 	if (do_set3(IP_FW_NAT64CLAT_DESTROY, &oh.opheader, sizeof(oh)) != 0)
355 		err(EX_OSERR, "failed to destroy nat instance %s", name);
356 }
357 
358 /*
359  * Get nat64clat instance statistics.
360  * Request: [ ipfw_obj_header ]
361  * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ] ]
362  */
363 static int
364 nat64clat_get_stats(const char *name, uint8_t set,
365     struct ipfw_nat64clat_stats *stats)
366 {
367 	ipfw_obj_header *oh;
368 	ipfw_obj_ctlv *oc;
369 	size_t sz;
370 
371 	sz = sizeof(*oh) + sizeof(*oc) + sizeof(*stats);
372 	oh = calloc(1, sz);
373 	nat64clat_fill_ntlv(&oh->ntlv, name, set);
374 	if (do_get3(IP_FW_NAT64CLAT_STATS, &oh->opheader, &sz) == 0) {
375 		oc = (ipfw_obj_ctlv *)(oh + 1);
376 		memcpy(stats, oc + 1, sizeof(*stats));
377 		free(oh);
378 		return (0);
379 	}
380 	free(oh);
381 	return (-1);
382 }
383 
384 static void
385 nat64clat_stats(const char *name, uint8_t set)
386 {
387 	struct ipfw_nat64clat_stats stats;
388 
389 	if (nat64clat_get_stats(name, set, &stats) != 0)
390 		err(EX_OSERR, "Error retrieving stats");
391 
392 	if (g_co.use_set != 0 || set != 0)
393 		printf("set %u ", set);
394 	printf("nat64clat %s\n", name);
395 
396 	printf("\t%ju packets translated from IPv6 to IPv4\n",
397 	    (uintmax_t)stats.opcnt64);
398 	printf("\t%ju packets translated from IPv4 to IPv6\n",
399 	    (uintmax_t)stats.opcnt46);
400 	printf("\t%ju IPv6 fragments created\n",
401 	    (uintmax_t)stats.ofrags);
402 	printf("\t%ju IPv4 fragments received\n",
403 	    (uintmax_t)stats.ifrags);
404 	printf("\t%ju output packets dropped due to no bufs, etc.\n",
405 	    (uintmax_t)stats.oerrors);
406 	printf("\t%ju output packets discarded due to no IPv4 route\n",
407 	    (uintmax_t)stats.noroute4);
408 	printf("\t%ju output packets discarded due to no IPv6 route\n",
409 	    (uintmax_t)stats.noroute6);
410 	printf("\t%ju packets discarded due to unsupported protocol\n",
411 	    (uintmax_t)stats.noproto);
412 	printf("\t%ju packets discarded due to memory allocation problems\n",
413 	    (uintmax_t)stats.nomem);
414 	printf("\t%ju packets discarded due to some errors\n",
415 	    (uintmax_t)stats.dropped);
416 }
417 
418 /*
419  * Reset nat64clat instance statistics specified by @oh->ntlv.
420  * Request: [ ipfw_obj_header ]
421  */
422 static void
423 nat64clat_reset_stats(const char *name, uint8_t set)
424 {
425 	ipfw_obj_header oh;
426 
427 	memset(&oh, 0, sizeof(oh));
428 	nat64clat_fill_ntlv(&oh.ntlv, name, set);
429 	if (do_set3(IP_FW_NAT64CLAT_RESET_STATS, &oh.opheader, sizeof(oh)) != 0)
430 		err(EX_OSERR, "failed to reset stats for instance %s", name);
431 }
432 
433 static int
434 nat64clat_show_cb(ipfw_nat64clat_cfg *cfg, const char *name, uint8_t set)
435 {
436 	char plat_buf[INET6_ADDRSTRLEN], clat_buf[INET6_ADDRSTRLEN];
437 
438 	if (name != NULL && strcmp(cfg->name, name) != 0)
439 		return (ESRCH);
440 
441 	if (g_co.use_set != 0 && cfg->set != set)
442 		return (ESRCH);
443 
444 	if (g_co.use_set != 0 || cfg->set != 0)
445 		printf("set %u ", cfg->set);
446 
447 	inet_ntop(AF_INET6, &cfg->clat_prefix, clat_buf, sizeof(clat_buf));
448 	inet_ntop(AF_INET6, &cfg->plat_prefix, plat_buf, sizeof(plat_buf));
449 	printf("nat64clat %s clat_prefix %s/%u plat_prefix %s/%u",
450 	    cfg->name, clat_buf, cfg->clat_plen, plat_buf, cfg->plat_plen);
451 	if (cfg->flags & NAT64_LOG)
452 		printf(" log");
453 	if (cfg->flags & NAT64_ALLOW_PRIVATE)
454 		printf(" allow_private");
455 	printf("\n");
456 	return (0);
457 }
458 
459 static int
460 nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name __unused,
461     uint8_t set)
462 {
463 
464 	if (g_co.use_set != 0 && cfg->set != set)
465 		return (ESRCH);
466 
467 	nat64clat_destroy(cfg->name, cfg->set);
468 	return (0);
469 }
470 
471 
472 /*
473  * Compare nat64clat instances names.
474  * Honor number comparison.
475  */
476 static int
477 nat64name_cmp(const void *a, const void *b)
478 {
479 	const ipfw_nat64clat_cfg *ca, *cb;
480 
481 	ca = (const ipfw_nat64clat_cfg *)a;
482 	cb = (const ipfw_nat64clat_cfg *)b;
483 
484 	if (ca->set > cb->set)
485 		return (1);
486 	else if (ca->set < cb->set)
487 		return (-1);
488 	return (stringnum_cmp(ca->name, cb->name));
489 }
490 
491 /*
492  * Retrieves nat64clat instance list from kernel,
493  * optionally sorts it and calls requested function for each instance.
494  *
495  * Request: [ ipfw_obj_lheader ]
496  * Reply: [ ipfw_obj_lheader ipfw_nat64clat_cfg x N ]
497  */
498 static int
499 nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set, int sort)
500 {
501 	ipfw_obj_lheader *olh;
502 	ipfw_nat64clat_cfg *cfg;
503 	size_t sz;
504 	uint32_t i;
505 
506 	/* Start with reasonable default */
507 	sz = sizeof(*olh) + 16 * sizeof(*cfg);
508 	for (;;) {
509 		if ((olh = calloc(1, sz)) == NULL)
510 			return (ENOMEM);
511 
512 		olh->size = sz;
513 		if (do_get3(IP_FW_NAT64CLAT_LIST, &olh->opheader, &sz) != 0) {
514 			sz = olh->size;
515 			free(olh);
516 			if (errno != ENOMEM)
517 				return (errno);
518 			continue;
519 		}
520 
521 		if (sort != 0)
522 			qsort(olh + 1, olh->count, olh->objsize,
523 			    nat64name_cmp);
524 
525 		cfg = (ipfw_nat64clat_cfg *)(olh + 1);
526 		for (i = 0; i < olh->count; i++) {
527 			(void)f(cfg, name, set); /* Ignore errors for now */
528 			cfg = (ipfw_nat64clat_cfg *)((caddr_t)cfg +
529 			    olh->objsize);
530 		}
531 		free(olh);
532 		break;
533 	}
534 	return (0);
535 }
536 
537