xref: /freebsd/sbin/ipfw/nat64stl.c (revision b11efc1eb69ff1e1cf7f2578f4db0b8ad18b6471)
1 /*-
2  * Copyright (c) 2015-2016 Yandex LLC
3  * Copyright (c) 2015-2016 Andrey V. Elsukov <ae@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
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 (nat64stl_cb_t)(ipfw_nat64stl_cfg *i, const char *name,
53     uint8_t set);
54 static int nat64stl_foreach(nat64stl_cb_t *f, const char *name, uint8_t set,
55     int sort);
56 
57 static void nat64stl_create(const char *name, uint8_t set, int ac, char **av);
58 static void nat64stl_config(const char *name, uint8_t set, int ac, char **av);
59 static void nat64stl_destroy(const char *name, uint8_t set);
60 static void nat64stl_stats(const char *name, uint8_t set);
61 static void nat64stl_reset_stats(const char *name, uint8_t set);
62 static int nat64stl_show_cb(ipfw_nat64stl_cfg *cfg, const char *name,
63     uint8_t set);
64 static int nat64stl_destroy_cb(ipfw_nat64stl_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 #define	IPV6_ADDR_INT32_WKPFX	htonl(0x64ff9b)
78 #define	IN6_IS_ADDR_WKPFX(a)					\
79     ((a)->__u6_addr.__u6_addr32[0] == IPV6_ADDR_INT32_WKPFX &&	\
80 	(a)->__u6_addr.__u6_addr32[1] == 0 &&			\
81 	(a)->__u6_addr.__u6_addr32[2] == 0)
82 int
83 ipfw_check_nat64prefix(const struct in6_addr *prefix, int length)
84 {
85 
86 	switch (length) {
87 	case 32:
88 	case 40:
89 	case 48:
90 	case 56:
91 	case 64:
92 		/* Well-known prefix has 96 prefix length */
93 		if (IN6_IS_ADDR_WKPFX(prefix))
94 			return (EINVAL);
95 		/* FALLTHROUGH */
96 	case 96:
97 		/* Bits 64 to 71 must be set to zero */
98 		if (prefix->__u6_addr.__u6_addr8[8] != 0)
99 			return (EINVAL);
100 		/* XXX: looks incorrect */
101 		if (IN6_IS_ADDR_MULTICAST(prefix) ||
102 		    IN6_IS_ADDR_UNSPECIFIED(prefix) ||
103 		    IN6_IS_ADDR_LOOPBACK(prefix))
104 			return (EINVAL);
105 		return (0);
106 	}
107 	return (EINVAL);
108 }
109 
110 static struct _s_x nat64statscmds[] = {
111       { "reset",	TOK_RESET },
112       { NULL, 0 }
113 };
114 
115 /*
116  * This one handles all nat64stl-related commands
117  *	ipfw [set N] nat64stl NAME {create | config} ...
118  *	ipfw [set N] nat64stl NAME stats [reset]
119  *	ipfw [set N] nat64stl {NAME | all} destroy
120  *	ipfw [set N] nat64stl {NAME | all} {list | show}
121  */
122 #define	nat64stl_check_name	table_check_name
123 void
124 ipfw_nat64stl_handler(int ac, char *av[])
125 {
126 	const char *name;
127 	int tcmd;
128 	uint8_t set;
129 
130 	if (co.use_set != 0)
131 		set = co.use_set - 1;
132 	else
133 		set = 0;
134 	ac--; av++;
135 
136 	NEED1("nat64stl needs instance name");
137 	name = *av;
138 	if (nat64stl_check_name(name) != 0) {
139 		if (strcmp(name, "all") == 0)
140 			name = NULL;
141 		else
142 			errx(EX_USAGE, "nat64stl instance name %s is invalid",
143 			    name);
144 	}
145 	ac--; av++;
146 	NEED1("nat64stl needs command");
147 
148 	tcmd = get_token(nat64cmds, *av, "nat64stl command");
149 	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
150 		errx(EX_USAGE, "nat64stl instance name required");
151 	switch (tcmd) {
152 	case TOK_CREATE:
153 		ac--; av++;
154 		nat64stl_create(name, set, ac, av);
155 		break;
156 	case TOK_CONFIG:
157 		ac--; av++;
158 		nat64stl_config(name, set, ac, av);
159 		break;
160 	case TOK_LIST:
161 		nat64stl_foreach(nat64stl_show_cb, name, set, 1);
162 		break;
163 	case TOK_DESTROY:
164 		if (name == NULL)
165 			nat64stl_foreach(nat64stl_destroy_cb, NULL, set, 0);
166 		else
167 			nat64stl_destroy(name, set);
168 		break;
169 	case TOK_STATS:
170 		ac--; av++;
171 		if (ac == 0) {
172 			nat64stl_stats(name, set);
173 			break;
174 		}
175 		tcmd = get_token(nat64statscmds, *av, "stats command");
176 		if (tcmd == TOK_RESET)
177 			nat64stl_reset_stats(name, set);
178 	}
179 }
180 
181 
182 static void
183 nat64stl_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
184 {
185 
186 	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
187 	ntlv->head.length = sizeof(ipfw_obj_ntlv);
188 	ntlv->idx = 1;
189 	ntlv->set = set;
190 	strlcpy(ntlv->name, name, sizeof(ntlv->name));
191 }
192 
193 static struct _s_x nat64newcmds[] = {
194       { "table4",	TOK_TABLE4 },
195       { "table6",	TOK_TABLE6 },
196       { "prefix6",	TOK_PREFIX6 },
197       { "log",		TOK_LOG },
198       { "-log",		TOK_LOGOFF },
199       { "allow_private", TOK_PRIVATE },
200       { "-allow_private", TOK_PRIVATEOFF },
201       { NULL, 0 }
202 };
203 
204 /*
205  * Creates new nat64stl instance
206  * ipfw nat64stl <NAME> create table4 <name> table6 <name> [ prefix6 <prefix>]
207  * Request: [ ipfw_obj_lheader ipfw_nat64stl_cfg ]
208  */
209 #define	NAT64STL_HAS_TABLE4	0x01
210 #define	NAT64STL_HAS_TABLE6	0x02
211 #define	NAT64STL_HAS_PREFIX6	0x04
212 static void
213 nat64stl_create(const char *name, uint8_t set, int ac, char *av[])
214 {
215 	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nat64stl_cfg)];
216 	ipfw_nat64stl_cfg *cfg;
217 	ipfw_obj_lheader *olh;
218 	int tcmd, flags;
219 	char *p;
220 
221 	memset(buf, 0, sizeof(buf));
222 	olh = (ipfw_obj_lheader *)buf;
223 	cfg = (ipfw_nat64stl_cfg *)(olh + 1);
224 
225 	/* Some reasonable defaults */
226 	inet_pton(AF_INET6, "64:ff9b::", &cfg->prefix6);
227 	cfg->plen6 = 96;
228 	cfg->set = set;
229 	flags = NAT64STL_HAS_PREFIX6;
230 	while (ac > 0) {
231 		tcmd = get_token(nat64newcmds, *av, "option");
232 		ac--; av++;
233 
234 		switch (tcmd) {
235 		case TOK_TABLE4:
236 			NEED1("table name required");
237 			table_fill_ntlv(&cfg->ntlv4, *av, set, 4);
238 			flags |= NAT64STL_HAS_TABLE4;
239 			ac--; av++;
240 			break;
241 		case TOK_TABLE6:
242 			NEED1("table name required");
243 			table_fill_ntlv(&cfg->ntlv6, *av, set, 6);
244 			flags |= NAT64STL_HAS_TABLE6;
245 			ac--; av++;
246 			break;
247 		case TOK_PREFIX6:
248 			NEED1("IPv6 prefix6 required");
249 			if ((p = strchr(*av, '/')) != NULL)
250 				*p++ = '\0';
251 			if (inet_pton(AF_INET6, *av, &cfg->prefix6) != 1)
252 				errx(EX_USAGE,
253 				    "Bad prefix: %s", *av);
254 			cfg->plen6 = strtol(p, NULL, 10);
255 			if (ipfw_check_nat64prefix(&cfg->prefix6,
256 			    cfg->plen6) != 0)
257 				errx(EX_USAGE,
258 				    "Bad prefix length: %s", p);
259 			flags |= NAT64STL_HAS_PREFIX6;
260 			ac--; av++;
261 			break;
262 		case TOK_LOG:
263 			cfg->flags |= NAT64_LOG;
264 			break;
265 		case TOK_LOGOFF:
266 			cfg->flags &= ~NAT64_LOG;
267 			break;
268 		case TOK_PRIVATE:
269 			cfg->flags |= NAT64_ALLOW_PRIVATE;
270 			break;
271 		case TOK_PRIVATEOFF:
272 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
273 			break;
274 		}
275 	}
276 
277 	/* Check validness */
278 	if ((flags & NAT64STL_HAS_TABLE4) != NAT64STL_HAS_TABLE4)
279 		errx(EX_USAGE, "table4 required");
280 	if ((flags & NAT64STL_HAS_TABLE6) != NAT64STL_HAS_TABLE6)
281 		errx(EX_USAGE, "table6 required");
282 	if ((flags & NAT64STL_HAS_PREFIX6) != NAT64STL_HAS_PREFIX6)
283 		errx(EX_USAGE, "prefix6 required");
284 
285 	olh->count = 1;
286 	olh->objsize = sizeof(*cfg);
287 	olh->size = sizeof(buf);
288 	strlcpy(cfg->name, name, sizeof(cfg->name));
289 	if (do_set3(IP_FW_NAT64STL_CREATE, &olh->opheader, sizeof(buf)) != 0)
290 		err(EX_OSERR, "nat64stl instance creation failed");
291 }
292 
293 /*
294  * Configures existing nat64stl instance
295  * ipfw nat64stl <NAME> config <options>
296  * Request: [ ipfw_obj_header ipfw_nat64stl_cfg ]
297  */
298 static void
299 nat64stl_config(const char *name, uint8_t set, int ac, char **av)
300 {
301 	char buf[sizeof(ipfw_obj_header) + sizeof(ipfw_nat64stl_cfg)];
302 	ipfw_nat64stl_cfg *cfg;
303 	ipfw_obj_header *oh;
304 	char *opt;
305 	size_t sz;
306 	int tcmd;
307 
308 	if (ac == 0)
309 		errx(EX_USAGE, "config options required");
310 	memset(&buf, 0, sizeof(buf));
311 	oh = (ipfw_obj_header *)buf;
312 	cfg = (ipfw_nat64stl_cfg *)(oh + 1);
313 	sz = sizeof(buf);
314 
315 	nat64stl_fill_ntlv(&oh->ntlv, name, set);
316 	if (do_get3(IP_FW_NAT64STL_CONFIG, &oh->opheader, &sz) != 0)
317 		err(EX_OSERR, "failed to get config for instance %s", name);
318 
319 	while (ac > 0) {
320 		tcmd = get_token(nat64newcmds, *av, "option");
321 		opt = *av;
322 		ac--; av++;
323 
324 		switch (tcmd) {
325 #if 0
326 		case TOK_TABLE4:
327 			NEED1("table name required");
328 			table_fill_ntlv(&cfg->ntlv4, *av, set, 4);
329 			ac--; av++;
330 			break;
331 		case TOK_TABLE6:
332 			NEED1("table name required");
333 			table_fill_ntlv(&cfg->ntlv6, *av, set, 6);
334 			ac--; av++;
335 			break;
336 #endif
337 		case TOK_LOG:
338 			cfg->flags |= NAT64_LOG;
339 			break;
340 		case TOK_LOGOFF:
341 			cfg->flags &= ~NAT64_LOG;
342 			break;
343 		case TOK_PRIVATE:
344 			cfg->flags |= NAT64_ALLOW_PRIVATE;
345 			break;
346 		case TOK_PRIVATEOFF:
347 			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
348 			break;
349 		default:
350 			errx(EX_USAGE, "Can't change %s option", opt);
351 		}
352 	}
353 
354 	if (do_set3(IP_FW_NAT64STL_CONFIG, &oh->opheader, sizeof(buf)) != 0)
355 		err(EX_OSERR, "nat64stl instance configuration failed");
356 }
357 
358 /*
359  * Destroys nat64stl instance.
360  * Request: [ ipfw_obj_header ]
361  */
362 static void
363 nat64stl_destroy(const char *name, uint8_t set)
364 {
365 	ipfw_obj_header oh;
366 
367 	memset(&oh, 0, sizeof(oh));
368 	nat64stl_fill_ntlv(&oh.ntlv, name, set);
369 	if (do_set3(IP_FW_NAT64STL_DESTROY, &oh.opheader, sizeof(oh)) != 0)
370 		err(EX_OSERR, "failed to destroy nat instance %s", name);
371 }
372 
373 /*
374  * Get nat64stl instance statistics.
375  * Request: [ ipfw_obj_header ]
376  * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ] ]
377  */
378 static int
379 nat64stl_get_stats(const char *name, uint8_t set,
380     struct ipfw_nat64stl_stats *stats)
381 {
382 	ipfw_obj_header *oh;
383 	ipfw_obj_ctlv *oc;
384 	size_t sz;
385 
386 	sz = sizeof(*oh) + sizeof(*oc) + sizeof(*stats);
387 	oh = calloc(1, sz);
388 	nat64stl_fill_ntlv(&oh->ntlv, name, set);
389 	if (do_get3(IP_FW_NAT64STL_STATS, &oh->opheader, &sz) == 0) {
390 		oc = (ipfw_obj_ctlv *)(oh + 1);
391 		memcpy(stats, oc + 1, sizeof(*stats));
392 		free(oh);
393 		return (0);
394 	}
395 	free(oh);
396 	return (-1);
397 }
398 
399 static void
400 nat64stl_stats(const char *name, uint8_t set)
401 {
402 	struct ipfw_nat64stl_stats stats;
403 
404 	if (nat64stl_get_stats(name, set, &stats) != 0)
405 		err(EX_OSERR, "Error retrieving stats");
406 
407 	if (co.use_set != 0 || set != 0)
408 		printf("set %u ", set);
409 	printf("nat64stl %s\n", name);
410 
411 	printf("\t%ju packets translated from IPv6 to IPv4\n",
412 	    (uintmax_t)stats.opcnt64);
413 	printf("\t%ju packets translated from IPv4 to IPv6\n",
414 	    (uintmax_t)stats.opcnt46);
415 	printf("\t%ju IPv6 fragments created\n",
416 	    (uintmax_t)stats.ofrags);
417 	printf("\t%ju IPv4 fragments received\n",
418 	    (uintmax_t)stats.ifrags);
419 	printf("\t%ju output packets dropped due to no bufs, etc.\n",
420 	    (uintmax_t)stats.oerrors);
421 	printf("\t%ju output packets discarded due to no IPv4 route\n",
422 	    (uintmax_t)stats.noroute4);
423 	printf("\t%ju output packets discarded due to no IPv6 route\n",
424 	    (uintmax_t)stats.noroute6);
425 	printf("\t%ju packets discarded due to unsupported protocol\n",
426 	    (uintmax_t)stats.noproto);
427 	printf("\t%ju packets discarded due to memory allocation problems\n",
428 	    (uintmax_t)stats.nomem);
429 	printf("\t%ju packets discarded due to some errors\n",
430 	    (uintmax_t)stats.dropped);
431 }
432 
433 /*
434  * Reset nat64stl instance statistics specified by @oh->ntlv.
435  * Request: [ ipfw_obj_header ]
436  */
437 static void
438 nat64stl_reset_stats(const char *name, uint8_t set)
439 {
440 	ipfw_obj_header oh;
441 
442 	memset(&oh, 0, sizeof(oh));
443 	nat64stl_fill_ntlv(&oh.ntlv, name, set);
444 	if (do_set3(IP_FW_NAT64STL_RESET_STATS, &oh.opheader, sizeof(oh)) != 0)
445 		err(EX_OSERR, "failed to reset stats for instance %s", name);
446 }
447 
448 static int
449 nat64stl_show_cb(ipfw_nat64stl_cfg *cfg, const char *name, uint8_t set)
450 {
451 	char abuf[INET6_ADDRSTRLEN];
452 
453 	if (name != NULL && strcmp(cfg->name, name) != 0)
454 		return (ESRCH);
455 
456 	if (co.use_set != 0 && cfg->set != set)
457 		return (ESRCH);
458 
459 	if (co.use_set != 0 || cfg->set != 0)
460 		printf("set %u ", cfg->set);
461 
462 	printf("nat64stl %s table4 %s table6 %s",
463 	    cfg->name, cfg->ntlv4.name, cfg->ntlv6.name);
464 	inet_ntop(AF_INET6, &cfg->prefix6, abuf, sizeof(abuf));
465 	printf(" prefix6 %s/%u", abuf, cfg->plen6);
466 	if (cfg->flags & NAT64_LOG)
467 		printf(" log");
468 	if (cfg->flags & NAT64_ALLOW_PRIVATE)
469 		printf(" allow_private");
470 	printf("\n");
471 	return (0);
472 }
473 
474 static int
475 nat64stl_destroy_cb(ipfw_nat64stl_cfg *cfg, const char *name, uint8_t set)
476 {
477 
478 	if (co.use_set != 0 && cfg->set != set)
479 		return (ESRCH);
480 
481 	nat64stl_destroy(cfg->name, cfg->set);
482 	return (0);
483 }
484 
485 
486 /*
487  * Compare nat64stl instances names.
488  * Honor number comparison.
489  */
490 static int
491 nat64name_cmp(const void *a, const void *b)
492 {
493 	ipfw_nat64stl_cfg *ca, *cb;
494 
495 	ca = (ipfw_nat64stl_cfg *)a;
496 	cb = (ipfw_nat64stl_cfg *)b;
497 
498 	if (ca->set > cb->set)
499 		return (1);
500 	else if (ca->set < cb->set)
501 		return (-1);
502 	return (stringnum_cmp(ca->name, cb->name));
503 }
504 
505 /*
506  * Retrieves nat64stl instance list from kernel,
507  * optionally sorts it and calls requested function for each instance.
508  *
509  * Request: [ ipfw_obj_lheader ]
510  * Reply: [ ipfw_obj_lheader ipfw_nat64stl_cfg x N ]
511  */
512 static int
513 nat64stl_foreach(nat64stl_cb_t *f, const char *name, uint8_t set, int sort)
514 {
515 	ipfw_obj_lheader *olh;
516 	ipfw_nat64stl_cfg *cfg;
517 	size_t sz;
518 	int i, error;
519 
520 	/* Start with reasonable default */
521 	sz = sizeof(*olh) + 16 * sizeof(*cfg);
522 	for (;;) {
523 		if ((olh = calloc(1, sz)) == NULL)
524 			return (ENOMEM);
525 
526 		olh->size = sz;
527 		if (do_get3(IP_FW_NAT64STL_LIST, &olh->opheader, &sz) != 0) {
528 			sz = olh->size;
529 			free(olh);
530 			if (errno != ENOMEM)
531 				return (errno);
532 			continue;
533 		}
534 
535 		if (sort != 0)
536 			qsort(olh + 1, olh->count, olh->objsize,
537 			    nat64name_cmp);
538 
539 		cfg = (ipfw_nat64stl_cfg *)(olh + 1);
540 		for (i = 0; i < olh->count; i++) {
541 			error = f(cfg, name, set); /* Ignore errors for now */
542 			cfg = (ipfw_nat64stl_cfg *)((caddr_t)cfg +
543 			    olh->objsize);
544 		}
545 		free(olh);
546 		break;
547 	}
548 	return (0);
549 }
550 
551