xref: /freebsd/sbin/ipfw/nat64clat.c (revision 5e3190f700637fcfc1a52daeaa4a031fdd2557c7) 
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/cdefs.h>
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 
34 #include "ipfw2.h"
35 
36 #include <ctype.h>
37 #include <err.h>
38 #include <errno.h>
39 #include <inttypes.h>
40 #include <netdb.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <sysexits.h>
45 
46 #include <net/if.h>
47 #include <netinet/in.h>
48 #include <netinet/ip_fw.h>
49 #include <netinet6/ip_fw_nat64.h>
50 #include <arpa/inet.h>
51 
52 typedef int (nat64clat_cb_t)(ipfw_nat64clat_cfg *i, const char *name,
53     uint8_t set);
54 static int nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set,
55     int sort);
56 
57 static void nat64clat_create(const char *name, uint8_t set, int ac, char **av);
58 static void nat64clat_config(const char *name, uint8_t set, int ac, char **av);
59 static void nat64clat_destroy(const char *name, uint8_t set);
60 static void nat64clat_stats(const char *name, uint8_t set);
61 static void nat64clat_reset_stats(const char *name, uint8_t set);
62 static int nat64clat_show_cb(ipfw_nat64clat_cfg *cfg, const char *name,
63     uint8_t set);
64 static int nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name,
65     uint8_t set);
66 
67 static struct _s_x nat64cmds[] = {
68       { "create",	TOK_CREATE },
69       { "config",	TOK_CONFIG },
70       { "destroy",	TOK_DESTROY },
71       { "list",		TOK_LIST },
72       { "show",		TOK_LIST },
73       { "stats",	TOK_STATS },
74       { NULL, 0 }
75 };
76 
77 static struct _s_x nat64statscmds[] = {
78       { "reset",	TOK_RESET },
79       { NULL, 0 }
80 };
81 
82 /*
83  * This one handles all nat64clat-related commands
84  *	ipfw [set N] nat64clat NAME {create | config} ...
85  *	ipfw [set N] nat64clat NAME stats [reset]
86  *	ipfw [set N] nat64clat {NAME | all} destroy
87  *	ipfw [set N] nat64clat {NAME | all} {list | show}
88  */
89 #define	nat64clat_check_name	table_check_name
90 void
91 ipfw_nat64clat_handler(int ac, char *av[])
92 {
93 	const char *name;
94 	int tcmd;
95 	uint8_t set;
96 
97 	if (g_co.use_set != 0)
98 		set = g_co.use_set - 1;
99 	else
100 		set = 0;
101 	ac--; av++;
102 
103 	NEED1("nat64clat needs instance name");
104 	name = *av;
105 	if (nat64clat_check_name(name) != 0) {
106 		if (strcmp(name, "all") == 0)
107 			name = NULL;
108 		else
109 			errx(EX_USAGE, "nat64clat instance name %s is invalid",
110 			    name);
111 	}
112 	ac--; av++;
113 	NEED1("nat64clat needs command");
114 
115 	tcmd = get_token(nat64cmds, *av, "nat64clat command");
116 	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
117 		errx(EX_USAGE, "nat64clat instance name required");
118 	switch (tcmd) {
119 	case TOK_CREATE:
120 		ac--; av++;
121 		nat64clat_create(name, set, ac, av);
122 		break;
123 	case TOK_CONFIG:
124 		ac--; av++;
125 		nat64clat_config(name, set, ac, av);
126 		break;
127 	case TOK_LIST:
128 		nat64clat_foreach(nat64clat_show_cb, name, set, 1);
129 		break;
130 	case TOK_DESTROY:
131 		if (name == NULL)
132 			nat64clat_foreach(nat64clat_destroy_cb, NULL, set, 0);
133 		else
134 			nat64clat_destroy(name, set);
135 		break;
136 	case TOK_STATS:
137 		ac--; av++;
138 		if (ac == 0) {
139 			nat64clat_stats(name, set);
140 			break;
141 		}
142 		tcmd = get_token(nat64statscmds, *av, "stats command");
143 		if (tcmd == TOK_RESET)
144 			nat64clat_reset_stats(name, set);
145 	}
146 }
147 
148 
149 static void
150 nat64clat_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
151 {
152 
153 	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
154 	ntlv->head.length = sizeof(ipfw_obj_ntlv);
155 	ntlv->idx = 1;
156 	ntlv->set = set;
157 	strlcpy(ntlv->name, name, sizeof(ntlv->name));
158 }
159 
160 static struct _s_x nat64newcmds[] = {
161       { "plat_prefix",	TOK_PLAT_PREFIX },
162       { "clat_prefix",	TOK_CLAT_PREFIX },
163       { "log",		TOK_LOG },
164       { "-log",		TOK_LOGOFF },
165       { "allow_private", TOK_PRIVATE },
166       { "-allow_private", TOK_PRIVATEOFF },
167       { NULL, 0 }
168 };
169 
170 /*
171  * Creates new nat64clat instance
172  * ipfw nat64clat <NAME> create clat_prefix <prefix> plat_prefix <prefix>
173  * Request: [ ipfw_obj_lheader ipfw_nat64clat_cfg ]
174  */
175 #define	NAT64CLAT_HAS_CLAT_PREFIX	0x01
176 #define	NAT64CLAT_HAS_PLAT_PREFIX	0x02
177 static void
178 nat64clat_create(const char *name, uint8_t set, int ac, char *av[])
179 {
180 	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nat64clat_cfg)];
181 	ipfw_nat64clat_cfg *cfg;
182 	ipfw_obj_lheader *olh;
183 	int tcmd, flags;
184 	char *p;
185 	struct in6_addr prefix;
186 	uint8_t plen;
187 
188 	memset(buf, 0, sizeof(buf));
189 	olh = (ipfw_obj_lheader *)buf;
190 	cfg = (ipfw_nat64clat_cfg *)(olh + 1);
191 
192 	/* Some reasonable defaults */
193 	inet_pton(AF_INET6, "64:ff9b::", &cfg->plat_prefix);
194 	cfg->plat_plen = 96;
195 	cfg->set = set;
196 	flags = NAT64CLAT_HAS_PLAT_PREFIX;
197 	while (ac > 0) {
198 		tcmd = get_token(nat64newcmds, *av, "option");
199 		ac--; av++;
200 
201 		switch (tcmd) {
202 		case TOK_PLAT_PREFIX:
203 		case TOK_CLAT_PREFIX:
204 			if (tcmd == TOK_PLAT_PREFIX) {
205 				NEED1("IPv6 plat_prefix required");
206 			} else {
207 				NEED1("IPv6 clat_prefix required");
208 			}
209 
210 			if ((p = strchr(*av, '/')) != NULL)
211 				*p++ = '\0';
212 			if (inet_pton(AF_INET6, *av, &prefix) != 1)
213 				errx(EX_USAGE,
214 				    "Bad prefix: %s", *av);
215 			plen = strtol(p, NULL, 10);
216 			if (ipfw_check_nat64prefix(&prefix, plen) != 0)
217 				errx(EX_USAGE,
218 				    "Bad prefix length: %s", p);
219 			if (tcmd == TOK_PLAT_PREFIX) {
220 				flags |= NAT64CLAT_HAS_PLAT_PREFIX;
221 				cfg->plat_prefix = prefix;
222 				cfg->plat_plen = plen;
223 			} else {
224 				flags |= NAT64CLAT_HAS_CLAT_PREFIX;
225 				cfg->clat_prefix = prefix;
226 				cfg->clat_plen = plen;
227 			}
228 			ac--; av++;
229 			break;
230 		case TOK_LOG:
231 			cfg->flags |= NAT64_LOG;
232 			break;
233 		case TOK_LOGOFF:
234 			cfg->flags &= ~NAT64_LOG;
235 			break;
236 		case TOK_PRIVATE:
237 			cfg->flags |= NAT64_ALLOW_PRIVATE;
238 			break;
239 		case TOK_PRIVATEOFF:
240 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
241 			break;
242 		}
243 	}
244 
245 	/* Check validness */
246 	if ((flags & NAT64CLAT_HAS_PLAT_PREFIX) != NAT64CLAT_HAS_PLAT_PREFIX)
247 		errx(EX_USAGE, "plat_prefix required");
248 	if ((flags & NAT64CLAT_HAS_CLAT_PREFIX) != NAT64CLAT_HAS_CLAT_PREFIX)
249 		errx(EX_USAGE, "clat_prefix required");
250 
251 	olh->count = 1;
252 	olh->objsize = sizeof(*cfg);
253 	olh->size = sizeof(buf);
254 	strlcpy(cfg->name, name, sizeof(cfg->name));
255 	if (do_set3(IP_FW_NAT64CLAT_CREATE, &olh->opheader, sizeof(buf)) != 0)
256 		err(EX_OSERR, "nat64clat instance creation failed");
257 }
258 
259 /*
260  * Configures existing nat64clat instance
261  * ipfw nat64clat <NAME> config <options>
262  * Request: [ ipfw_obj_header ipfw_nat64clat_cfg ]
263  */
264 static void
265 nat64clat_config(const char *name, uint8_t set, int ac, char **av)
266 {
267 	char buf[sizeof(ipfw_obj_header) + sizeof(ipfw_nat64clat_cfg)];
268 	ipfw_nat64clat_cfg *cfg;
269 	ipfw_obj_header *oh;
270 	char *opt;
271 	char *p;
272 	size_t sz;
273 	int tcmd;
274 	struct in6_addr prefix;
275 	uint8_t plen;
276 
277 	if (ac == 0)
278 		errx(EX_USAGE, "config options required");
279 	memset(&buf, 0, sizeof(buf));
280 	oh = (ipfw_obj_header *)buf;
281 	cfg = (ipfw_nat64clat_cfg *)(oh + 1);
282 	sz = sizeof(buf);
283 
284 	nat64clat_fill_ntlv(&oh->ntlv, name, set);
285 	if (do_get3(IP_FW_NAT64CLAT_CONFIG, &oh->opheader, &sz) != 0)
286 		err(EX_OSERR, "failed to get config for instance %s", name);
287 
288 	while (ac > 0) {
289 		tcmd = get_token(nat64newcmds, *av, "option");
290 		opt = *av;
291 		ac--; av++;
292 
293 		switch (tcmd) {
294 		case TOK_PLAT_PREFIX:
295 		case TOK_CLAT_PREFIX:
296 			if (tcmd == TOK_PLAT_PREFIX) {
297 				NEED1("IPv6 plat_prefix required");
298 			} else {
299 				NEED1("IPv6 clat_prefix required");
300 			}
301 
302 			if ((p = strchr(*av, '/')) != NULL)
303 				*p++ = '\0';
304 			else
305 				errx(EX_USAGE,
306 				    "Prefix length required: %s", *av);
307 			if (inet_pton(AF_INET6, *av, &prefix) != 1)
308 				errx(EX_USAGE,
309 				    "Bad prefix: %s", *av);
310 			plen = strtol(p, NULL, 10);
311 			if (ipfw_check_nat64prefix(&prefix, plen) != 0)
312 				errx(EX_USAGE,
313 				    "Bad prefix length: %s", p);
314 			if (tcmd == TOK_PLAT_PREFIX) {
315 				cfg->plat_prefix = prefix;
316 				cfg->plat_plen = plen;
317 			} else {
318 				cfg->clat_prefix = prefix;
319 				cfg->clat_plen = plen;
320 			}
321 			ac--; av++;
322 			break;
323 		case TOK_LOG:
324 			cfg->flags |= NAT64_LOG;
325 			break;
326 		case TOK_LOGOFF:
327 			cfg->flags &= ~NAT64_LOG;
328 			break;
329 		case TOK_PRIVATE:
330 			cfg->flags |= NAT64_ALLOW_PRIVATE;
331 			break;
332 		case TOK_PRIVATEOFF:
333 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
334 			break;
335 		default:
336 			errx(EX_USAGE, "Can't change %s option", opt);
337 		}
338 	}
339 
340 	if (do_set3(IP_FW_NAT64CLAT_CONFIG, &oh->opheader, sizeof(buf)) != 0)
341 		err(EX_OSERR, "nat64clat instance configuration failed");
342 }
343 
344 /*
345  * Destroys nat64clat instance.
346  * Request: [ ipfw_obj_header ]
347  */
348 static void
349 nat64clat_destroy(const char *name, uint8_t set)
350 {
351 	ipfw_obj_header oh;
352 
353 	memset(&oh, 0, sizeof(oh));
354 	nat64clat_fill_ntlv(&oh.ntlv, name, set);
355 	if (do_set3(IP_FW_NAT64CLAT_DESTROY, &oh.opheader, sizeof(oh)) != 0)
356 		err(EX_OSERR, "failed to destroy nat instance %s", name);
357 }
358 
359 /*
360  * Get nat64clat instance statistics.
361  * Request: [ ipfw_obj_header ]
362  * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ] ]
363  */
364 static int
365 nat64clat_get_stats(const char *name, uint8_t set,
366     struct ipfw_nat64clat_stats *stats)
367 {
368 	ipfw_obj_header *oh;
369 	ipfw_obj_ctlv *oc;
370 	size_t sz;
371 
372 	sz = sizeof(*oh) + sizeof(*oc) + sizeof(*stats);
373 	oh = calloc(1, sz);
374 	nat64clat_fill_ntlv(&oh->ntlv, name, set);
375 	if (do_get3(IP_FW_NAT64CLAT_STATS, &oh->opheader, &sz) == 0) {
376 		oc = (ipfw_obj_ctlv *)(oh + 1);
377 		memcpy(stats, oc + 1, sizeof(*stats));
378 		free(oh);
379 		return (0);
380 	}
381 	free(oh);
382 	return (-1);
383 }
384 
385 static void
386 nat64clat_stats(const char *name, uint8_t set)
387 {
388 	struct ipfw_nat64clat_stats stats;
389 
390 	if (nat64clat_get_stats(name, set, &stats) != 0)
391 		err(EX_OSERR, "Error retrieving stats");
392 
393 	if (g_co.use_set != 0 || set != 0)
394 		printf("set %u ", set);
395 	printf("nat64clat %s\n", name);
396 
397 	printf("\t%ju packets translated from IPv6 to IPv4\n",
398 	    (uintmax_t)stats.opcnt64);
399 	printf("\t%ju packets translated from IPv4 to IPv6\n",
400 	    (uintmax_t)stats.opcnt46);
401 	printf("\t%ju IPv6 fragments created\n",
402 	    (uintmax_t)stats.ofrags);
403 	printf("\t%ju IPv4 fragments received\n",
404 	    (uintmax_t)stats.ifrags);
405 	printf("\t%ju output packets dropped due to no bufs, etc.\n",
406 	    (uintmax_t)stats.oerrors);
407 	printf("\t%ju output packets discarded due to no IPv4 route\n",
408 	    (uintmax_t)stats.noroute4);
409 	printf("\t%ju output packets discarded due to no IPv6 route\n",
410 	    (uintmax_t)stats.noroute6);
411 	printf("\t%ju packets discarded due to unsupported protocol\n",
412 	    (uintmax_t)stats.noproto);
413 	printf("\t%ju packets discarded due to memory allocation problems\n",
414 	    (uintmax_t)stats.nomem);
415 	printf("\t%ju packets discarded due to some errors\n",
416 	    (uintmax_t)stats.dropped);
417 }
418 
419 /*
420  * Reset nat64clat instance statistics specified by @oh->ntlv.
421  * Request: [ ipfw_obj_header ]
422  */
423 static void
424 nat64clat_reset_stats(const char *name, uint8_t set)
425 {
426 	ipfw_obj_header oh;
427 
428 	memset(&oh, 0, sizeof(oh));
429 	nat64clat_fill_ntlv(&oh.ntlv, name, set);
430 	if (do_set3(IP_FW_NAT64CLAT_RESET_STATS, &oh.opheader, sizeof(oh)) != 0)
431 		err(EX_OSERR, "failed to reset stats for instance %s", name);
432 }
433 
434 static int
435 nat64clat_show_cb(ipfw_nat64clat_cfg *cfg, const char *name, uint8_t set)
436 {
437 	char plat_buf[INET6_ADDRSTRLEN], clat_buf[INET6_ADDRSTRLEN];
438 
439 	if (name != NULL && strcmp(cfg->name, name) != 0)
440 		return (ESRCH);
441 
442 	if (g_co.use_set != 0 && cfg->set != set)
443 		return (ESRCH);
444 
445 	if (g_co.use_set != 0 || cfg->set != 0)
446 		printf("set %u ", cfg->set);
447 
448 	inet_ntop(AF_INET6, &cfg->clat_prefix, clat_buf, sizeof(clat_buf));
449 	inet_ntop(AF_INET6, &cfg->plat_prefix, plat_buf, sizeof(plat_buf));
450 	printf("nat64clat %s clat_prefix %s/%u plat_prefix %s/%u",
451 	    cfg->name, clat_buf, cfg->clat_plen, plat_buf, cfg->plat_plen);
452 	if (cfg->flags & NAT64_LOG)
453 		printf(" log");
454 	if (cfg->flags & NAT64_ALLOW_PRIVATE)
455 		printf(" allow_private");
456 	printf("\n");
457 	return (0);
458 }
459 
460 static int
461 nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name __unused,
462     uint8_t set)
463 {
464 
465 	if (g_co.use_set != 0 && cfg->set != set)
466 		return (ESRCH);
467 
468 	nat64clat_destroy(cfg->name, cfg->set);
469 	return (0);
470 }
471 
472 
473 /*
474  * Compare nat64clat instances names.
475  * Honor number comparison.
476  */
477 static int
478 nat64name_cmp(const void *a, const void *b)
479 {
480 	const ipfw_nat64clat_cfg *ca, *cb;
481 
482 	ca = (const ipfw_nat64clat_cfg *)a;
483 	cb = (const ipfw_nat64clat_cfg *)b;
484 
485 	if (ca->set > cb->set)
486 		return (1);
487 	else if (ca->set < cb->set)
488 		return (-1);
489 	return (stringnum_cmp(ca->name, cb->name));
490 }
491 
492 /*
493  * Retrieves nat64clat instance list from kernel,
494  * optionally sorts it and calls requested function for each instance.
495  *
496  * Request: [ ipfw_obj_lheader ]
497  * Reply: [ ipfw_obj_lheader ipfw_nat64clat_cfg x N ]
498  */
499 static int
500 nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set, int sort)
501 {
502 	ipfw_obj_lheader *olh;
503 	ipfw_nat64clat_cfg *cfg;
504 	size_t sz;
505 	uint32_t i;
506 
507 	/* Start with reasonable default */
508 	sz = sizeof(*olh) + 16 * sizeof(*cfg);
509 	for (;;) {
510 		if ((olh = calloc(1, sz)) == NULL)
511 			return (ENOMEM);
512 
513 		olh->size = sz;
514 		if (do_get3(IP_FW_NAT64CLAT_LIST, &olh->opheader, &sz) != 0) {
515 			sz = olh->size;
516 			free(olh);
517 			if (errno != ENOMEM)
518 				return (errno);
519 			continue;
520 		}
521 
522 		if (sort != 0)
523 			qsort(olh + 1, olh->count, olh->objsize,
524 			    nat64name_cmp);
525 
526 		cfg = (ipfw_nat64clat_cfg *)(olh + 1);
527 		for (i = 0; i < olh->count; i++) {
528 			(void)f(cfg, name, set); /* Ignore errors for now */
529 			cfg = (ipfw_nat64clat_cfg *)((caddr_t)cfg +
530 			    olh->objsize);
531 		}
532 		free(olh);
533 		break;
534 	}
535 	return (0);
536 }
537 
538