xref: /freebsd/sbin/ipfw/nat64stl.c (revision 6e4f4927ef8d86b2ef80ad3634ed4f19a886b7f4)
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 static int nat64stl_check_prefix(struct in6_addr *prefix, int length);
53 typedef int (nat64stl_cb_t)(ipfw_nat64stl_cfg *i, const char *name,
54     uint8_t set);
55 static int nat64stl_foreach(nat64stl_cb_t *f, const char *name, uint8_t set,
56     int sort);
57 
58 static void nat64stl_create(const char *name, uint8_t set, int ac, char **av);
59 static void nat64stl_config(const char *name, uint8_t set, int ac, char **av);
60 static void nat64stl_destroy(const char *name, uint8_t set);
61 static void nat64stl_stats(const char *name, uint8_t set);
62 static void nat64stl_reset_stats(const char *name, uint8_t set);
63 static int nat64stl_show_cb(ipfw_nat64stl_cfg *cfg, const char *name,
64     uint8_t set);
65 static int nat64stl_destroy_cb(ipfw_nat64stl_cfg *cfg, const char *name,
66     uint8_t set);
67 
68 static struct _s_x nat64cmds[] = {
69       { "create",	TOK_CREATE },
70       { "config",	TOK_CONFIG },
71       { "destroy",	TOK_DESTROY },
72       { "list",		TOK_LIST },
73       { "show",		TOK_LIST },
74       { "stats",	TOK_STATS },
75       { NULL, 0 }
76 };
77 
78 #define	IPV6_ADDR_INT32_WKPFX	htonl(0x64ff9b)
79 #define	IN6_IS_ADDR_WKPFX(a)					\
80     ((a)->__u6_addr.__u6_addr32[0] == IPV6_ADDR_INT32_WKPFX &&	\
81 	(a)->__u6_addr.__u6_addr32[1] == 0 &&			\
82 	(a)->__u6_addr.__u6_addr32[2] == 0)
83 static int
84 nat64stl_check_prefix(struct in6_addr *prefix, int length)
85 {
86 
87 	if (IN6_IS_ADDR_WKPFX(prefix) && length == 96)
88 		return (0);
89 #if 0
90 	switch (length) {
91 	case 32:
92 	case 40:
93 	case 48:
94 	case 56:
95 	case 64:
96 		/* Well-known prefix has 96 prefix length */
97 		if (IN6_IS_ADDR_WKPFX(prefix))
98 			return (1);
99 		/* FALLTHROUGH */
100 	case 96:
101 		/* Bits 64 to 71 must be set to zero */
102 		if (prefix->__u6_addr.__u6_addr8[8] != 0)
103 			return (1);
104 		/* XXX: looks incorrect */
105 		if (IN6_IS_ADDR_MULTICAST(prefix) ||
106 		    IN6_IS_ADDR_UNSPECIFIED(prefix) ||
107 		    IN6_IS_ADDR_LOOPBACK(prefix))
108 			return (1);
109 		return (0);
110 	}
111 #endif
112 	return (1);
113 }
114 
115 static struct _s_x nat64statscmds[] = {
116       { "reset",	TOK_RESET },
117       { NULL, 0 }
118 };
119 
120 /*
121  * This one handles all nat64stl-related commands
122  *	ipfw [set N] nat64stl NAME {create | config} ...
123  *	ipfw [set N] nat64stl NAME stats [reset]
124  *	ipfw [set N] nat64stl {NAME | all} destroy
125  *	ipfw [set N] nat64stl {NAME | all} {list | show}
126  */
127 #define	nat64stl_check_name	table_check_name
128 void
129 ipfw_nat64stl_handler(int ac, char *av[])
130 {
131 	const char *name;
132 	int tcmd;
133 	uint8_t set;
134 
135 	if (co.use_set != 0)
136 		set = co.use_set - 1;
137 	else
138 		set = 0;
139 	ac--; av++;
140 
141 	NEED1("nat64stl needs instance name");
142 	name = *av;
143 	if (nat64stl_check_name(name) != 0) {
144 		if (strcmp(name, "all") == 0)
145 			name = NULL;
146 		else
147 			errx(EX_USAGE, "nat64stl instance name %s is invalid",
148 			    name);
149 	}
150 	ac--; av++;
151 	NEED1("nat64stl needs command");
152 
153 	tcmd = get_token(nat64cmds, *av, "nat64stl command");
154 	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
155 		errx(EX_USAGE, "nat64stl instance name required");
156 	switch (tcmd) {
157 	case TOK_CREATE:
158 		ac--; av++;
159 		nat64stl_create(name, set, ac, av);
160 		break;
161 	case TOK_CONFIG:
162 		ac--; av++;
163 		nat64stl_config(name, set, ac, av);
164 		break;
165 	case TOK_LIST:
166 		nat64stl_foreach(nat64stl_show_cb, name, set, 1);
167 		break;
168 	case TOK_DESTROY:
169 		if (name == NULL)
170 			nat64stl_foreach(nat64stl_destroy_cb, NULL, set, 0);
171 		else
172 			nat64stl_destroy(name, set);
173 		break;
174 	case TOK_STATS:
175 		ac--; av++;
176 		if (ac == 0) {
177 			nat64stl_stats(name, set);
178 			break;
179 		}
180 		tcmd = get_token(nat64statscmds, *av, "stats command");
181 		if (tcmd == TOK_RESET)
182 			nat64stl_reset_stats(name, set);
183 	}
184 }
185 
186 
187 static void
188 nat64stl_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
189 {
190 
191 	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
192 	ntlv->head.length = sizeof(ipfw_obj_ntlv);
193 	ntlv->idx = 1;
194 	ntlv->set = set;
195 	strlcpy(ntlv->name, name, sizeof(ntlv->name));
196 }
197 
198 static struct _s_x nat64newcmds[] = {
199       { "table4",	TOK_TABLE4 },
200       { "table6",	TOK_TABLE6 },
201       { "prefix6",	TOK_PREFIX6 },
202       { "log",		TOK_LOG },
203       { "-log",		TOK_LOGOFF },
204       { NULL, 0 }
205 };
206 
207 /*
208  * Creates new nat64stl instance
209  * ipfw nat64stl <NAME> create table4 <name> table6 <name> [ prefix6 <prefix>]
210  * Request: [ ipfw_obj_lheader ipfw_nat64stl_cfg ]
211  */
212 #define	NAT64STL_HAS_TABLE4	0x01
213 #define	NAT64STL_HAS_TABLE6	0x02
214 #define	NAT64STL_HAS_PREFIX6	0x04
215 static void
216 nat64stl_create(const char *name, uint8_t set, int ac, char *av[])
217 {
218 	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nat64stl_cfg)];
219 	ipfw_nat64stl_cfg *cfg;
220 	ipfw_obj_lheader *olh;
221 	int tcmd, flags;
222 	char *p;
223 
224 	memset(buf, 0, sizeof(buf));
225 	olh = (ipfw_obj_lheader *)buf;
226 	cfg = (ipfw_nat64stl_cfg *)(olh + 1);
227 
228 	/* Some reasonable defaults */
229 	inet_pton(AF_INET6, "64:ff9b::", &cfg->prefix6);
230 	cfg->plen6 = 96;
231 	cfg->set = set;
232 	flags = NAT64STL_HAS_PREFIX6;
233 	while (ac > 0) {
234 		tcmd = get_token(nat64newcmds, *av, "option");
235 		ac--; av++;
236 
237 		switch (tcmd) {
238 		case TOK_TABLE4:
239 			NEED1("table name required");
240 			table_fill_ntlv(&cfg->ntlv4, *av, set, 4);
241 			flags |= NAT64STL_HAS_TABLE4;
242 			ac--; av++;
243 			break;
244 		case TOK_TABLE6:
245 			NEED1("table name required");
246 			table_fill_ntlv(&cfg->ntlv6, *av, set, 6);
247 			flags |= NAT64STL_HAS_TABLE6;
248 			ac--; av++;
249 			break;
250 		case TOK_PREFIX6:
251 			NEED1("IPv6 prefix6 required");
252 			if ((p = strchr(*av, '/')) != NULL)
253 				*p++ = '\0';
254 			if (inet_pton(AF_INET6, *av, &cfg->prefix6) != 1)
255 				errx(EX_USAGE,
256 				    "Bad prefix: %s", *av);
257 			cfg->plen6 = strtol(p, NULL, 10);
258 			if (nat64stl_check_prefix(&cfg->prefix6,
259 			    cfg->plen6) != 0)
260 				errx(EX_USAGE,
261 				    "Bad prefix length: %s", p);
262 			flags |= NAT64STL_HAS_PREFIX6;
263 			ac--; av++;
264 			break;
265 		case TOK_LOG:
266 			cfg->flags |= NAT64_LOG;
267 			break;
268 		case TOK_LOGOFF:
269 			cfg->flags &= ~NAT64_LOG;
270 			break;
271 		}
272 	}
273 
274 	/* Check validness */
275 	if ((flags & NAT64STL_HAS_TABLE4) != NAT64STL_HAS_TABLE4)
276 		errx(EX_USAGE, "table4 required");
277 	if ((flags & NAT64STL_HAS_TABLE6) != NAT64STL_HAS_TABLE6)
278 		errx(EX_USAGE, "table6 required");
279 	if ((flags & NAT64STL_HAS_PREFIX6) != NAT64STL_HAS_PREFIX6)
280 		errx(EX_USAGE, "prefix6 required");
281 
282 	olh->count = 1;
283 	olh->objsize = sizeof(*cfg);
284 	olh->size = sizeof(buf);
285 	strlcpy(cfg->name, name, sizeof(cfg->name));
286 	if (do_set3(IP_FW_NAT64STL_CREATE, &olh->opheader, sizeof(buf)) != 0)
287 		err(EX_OSERR, "nat64stl instance creation failed");
288 }
289 
290 /*
291  * Configures existing nat64stl instance
292  * ipfw nat64stl <NAME> config <options>
293  * Request: [ ipfw_obj_header ipfw_nat64stl_cfg ]
294  */
295 static void
296 nat64stl_config(const char *name, uint8_t set, int ac, char **av)
297 {
298 	char buf[sizeof(ipfw_obj_header) + sizeof(ipfw_nat64stl_cfg)];
299 	ipfw_nat64stl_cfg *cfg;
300 	ipfw_obj_header *oh;
301 	char *opt;
302 	size_t sz;
303 	int tcmd;
304 
305 	if (ac == 0)
306 		errx(EX_USAGE, "config options required");
307 	memset(&buf, 0, sizeof(buf));
308 	oh = (ipfw_obj_header *)buf;
309 	cfg = (ipfw_nat64stl_cfg *)(oh + 1);
310 	sz = sizeof(buf);
311 
312 	nat64stl_fill_ntlv(&oh->ntlv, name, set);
313 	if (do_get3(IP_FW_NAT64STL_CONFIG, &oh->opheader, &sz) != 0)
314 		err(EX_OSERR, "failed to get config for instance %s", name);
315 
316 	while (ac > 0) {
317 		tcmd = get_token(nat64newcmds, *av, "option");
318 		opt = *av;
319 		ac--; av++;
320 
321 		switch (tcmd) {
322 #if 0
323 		case TOK_TABLE4:
324 			NEED1("table name required");
325 			table_fill_ntlv(&cfg->ntlv4, *av, set, 4);
326 			ac--; av++;
327 			break;
328 		case TOK_TABLE6:
329 			NEED1("table name required");
330 			table_fill_ntlv(&cfg->ntlv6, *av, set, 6);
331 			ac--; av++;
332 			break;
333 #endif
334 		case TOK_LOG:
335 			cfg->flags |= NAT64_LOG;
336 			break;
337 		case TOK_LOGOFF:
338 			cfg->flags &= ~NAT64_LOG;
339 			break;
340 		default:
341 			errx(EX_USAGE, "Can't change %s option", opt);
342 		}
343 	}
344 
345 	if (do_set3(IP_FW_NAT64STL_CONFIG, &oh->opheader, sizeof(buf)) != 0)
346 		err(EX_OSERR, "nat64stl instance configuration failed");
347 }
348 
349 /*
350  * Destroys nat64stl instance.
351  * Request: [ ipfw_obj_header ]
352  */
353 static void
354 nat64stl_destroy(const char *name, uint8_t set)
355 {
356 	ipfw_obj_header oh;
357 
358 	memset(&oh, 0, sizeof(oh));
359 	nat64stl_fill_ntlv(&oh.ntlv, name, set);
360 	if (do_set3(IP_FW_NAT64STL_DESTROY, &oh.opheader, sizeof(oh)) != 0)
361 		err(EX_OSERR, "failed to destroy nat instance %s", name);
362 }
363 
364 /*
365  * Get nat64stl instance statistics.
366  * Request: [ ipfw_obj_header ]
367  * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ] ]
368  */
369 static int
370 nat64stl_get_stats(const char *name, uint8_t set,
371     struct ipfw_nat64stl_stats *stats)
372 {
373 	ipfw_obj_header *oh;
374 	ipfw_obj_ctlv *oc;
375 	size_t sz;
376 
377 	sz = sizeof(*oh) + sizeof(*oc) + sizeof(*stats);
378 	oh = calloc(1, sz);
379 	nat64stl_fill_ntlv(&oh->ntlv, name, set);
380 	if (do_get3(IP_FW_NAT64STL_STATS, &oh->opheader, &sz) == 0) {
381 		oc = (ipfw_obj_ctlv *)(oh + 1);
382 		memcpy(stats, oc + 1, sizeof(*stats));
383 		free(oh);
384 		return (0);
385 	}
386 	free(oh);
387 	return (-1);
388 }
389 
390 static void
391 nat64stl_stats(const char *name, uint8_t set)
392 {
393 	struct ipfw_nat64stl_stats stats;
394 
395 	if (nat64stl_get_stats(name, set, &stats) != 0)
396 		err(EX_OSERR, "Error retrieving stats");
397 
398 	if (co.use_set != 0 || set != 0)
399 		printf("set %u ", set);
400 	printf("nat64stl %s\n", name);
401 
402 	printf("\t%ju packets translated from IPv6 to IPv4\n",
403 	    (uintmax_t)stats.opcnt64);
404 	printf("\t%ju packets translated from IPv4 to IPv6\n",
405 	    (uintmax_t)stats.opcnt46);
406 	printf("\t%ju IPv6 fragments created\n",
407 	    (uintmax_t)stats.ofrags);
408 	printf("\t%ju IPv4 fragments received\n",
409 	    (uintmax_t)stats.ifrags);
410 	printf("\t%ju output packets dropped due to no bufs, etc.\n",
411 	    (uintmax_t)stats.oerrors);
412 	printf("\t%ju output packets discarded due to no IPv4 route\n",
413 	    (uintmax_t)stats.noroute4);
414 	printf("\t%ju output packets discarded due to no IPv6 route\n",
415 	    (uintmax_t)stats.noroute6);
416 	printf("\t%ju packets discarded due to unsupported protocol\n",
417 	    (uintmax_t)stats.noproto);
418 	printf("\t%ju packets discarded due to memory allocation problems\n",
419 	    (uintmax_t)stats.nomem);
420 	printf("\t%ju packets discarded due to some errors\n",
421 	    (uintmax_t)stats.dropped);
422 }
423 
424 /*
425  * Reset nat64stl instance statistics specified by @oh->ntlv.
426  * Request: [ ipfw_obj_header ]
427  */
428 static void
429 nat64stl_reset_stats(const char *name, uint8_t set)
430 {
431 	ipfw_obj_header oh;
432 
433 	memset(&oh, 0, sizeof(oh));
434 	nat64stl_fill_ntlv(&oh.ntlv, name, set);
435 	if (do_set3(IP_FW_NAT64STL_RESET_STATS, &oh.opheader, sizeof(oh)) != 0)
436 		err(EX_OSERR, "failed to reset stats for instance %s", name);
437 }
438 
439 static int
440 nat64stl_show_cb(ipfw_nat64stl_cfg *cfg, const char *name, uint8_t set)
441 {
442 
443 	if (name != NULL && strcmp(cfg->name, name) != 0)
444 		return (ESRCH);
445 
446 	if (co.use_set != 0 && cfg->set != set)
447 		return (ESRCH);
448 
449 	if (co.use_set != 0 || cfg->set != 0)
450 		printf("set %u ", cfg->set);
451 	printf("nat64stl %s table4 %s table6 %s",
452 	    cfg->name, cfg->ntlv4.name, cfg->ntlv6.name);
453 	if (cfg->flags & NAT64_LOG)
454 		printf(" log");
455 	printf("\n");
456 	return (0);
457 }
458 
459 static int
460 nat64stl_destroy_cb(ipfw_nat64stl_cfg *cfg, const char *name, uint8_t set)
461 {
462 
463 	if (co.use_set != 0 && cfg->set != set)
464 		return (ESRCH);
465 
466 	nat64stl_destroy(cfg->name, cfg->set);
467 	return (0);
468 }
469 
470 
471 /*
472  * Compare nat64stl instances names.
473  * Honor number comparison.
474  */
475 static int
476 nat64name_cmp(const void *a, const void *b)
477 {
478 	ipfw_nat64stl_cfg *ca, *cb;
479 
480 	ca = (ipfw_nat64stl_cfg *)a;
481 	cb = (ipfw_nat64stl_cfg *)b;
482 
483 	if (ca->set > cb->set)
484 		return (1);
485 	else if (ca->set < cb->set)
486 		return (-1);
487 	return (stringnum_cmp(ca->name, cb->name));
488 }
489 
490 /*
491  * Retrieves nat64stl instance list from kernel,
492  * optionally sorts it and calls requested function for each instance.
493  *
494  * Request: [ ipfw_obj_lheader ]
495  * Reply: [ ipfw_obj_lheader ipfw_nat64stl_cfg x N ]
496  */
497 static int
498 nat64stl_foreach(nat64stl_cb_t *f, const char *name, uint8_t set, int sort)
499 {
500 	ipfw_obj_lheader *olh;
501 	ipfw_nat64stl_cfg *cfg;
502 	size_t sz;
503 	int i, error;
504 
505 	/* Start with reasonable default */
506 	sz = sizeof(*olh) + 16 * sizeof(*cfg);
507 	for (;;) {
508 		if ((olh = calloc(1, sz)) == NULL)
509 			return (ENOMEM);
510 
511 		olh->size = sz;
512 		if (do_get3(IP_FW_NAT64STL_LIST, &olh->opheader, &sz) != 0) {
513 			sz = olh->size;
514 			free(olh);
515 			if (errno != ENOMEM)
516 				return (errno);
517 			continue;
518 		}
519 
520 		if (sort != 0)
521 			qsort(olh + 1, olh->count, olh->objsize,
522 			    nat64name_cmp);
523 
524 		cfg = (ipfw_nat64stl_cfg *)(olh + 1);
525 		for (i = 0; i < olh->count; i++) {
526 			error = f(cfg, name, set); /* Ignore errors for now */
527 			cfg = (ipfw_nat64stl_cfg *)((caddr_t)cfg +
528 			    olh->objsize);
529 		}
530 		free(olh);
531 		break;
532 	}
533 	return (0);
534 }
535 
536