nat64clat.c revision 346212 
1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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__FBSDID("$FreeBSD: stable/11/sbin/ipfw/nat64clat.c 346212 2019-04-14 12:39:09Z ae $");
32
33#include <sys/types.h>
34#include <sys/socket.h>
35
36#include "ipfw2.h"
37
38#include <ctype.h>
39#include <err.h>
40#include <errno.h>
41#include <inttypes.h>
42#include <netdb.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <sysexits.h>
47
48#include <net/if.h>
49#include <netinet/in.h>
50#include <netinet/ip_fw.h>
51#include <netinet6/ip_fw_nat64.h>
52#include <arpa/inet.h>
53
54typedef int (nat64clat_cb_t)(ipfw_nat64clat_cfg *i, const char *name,
55    uint8_t set);
56static int nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set,
57    int sort);
58
59static void nat64clat_create(const char *name, uint8_t set, int ac, char **av);
60static void nat64clat_config(const char *name, uint8_t set, int ac, char **av);
61static void nat64clat_destroy(const char *name, uint8_t set);
62static void nat64clat_stats(const char *name, uint8_t set);
63static void nat64clat_reset_stats(const char *name, uint8_t set);
64static int nat64clat_show_cb(ipfw_nat64clat_cfg *cfg, const char *name,
65    uint8_t set);
66static int nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name,
67    uint8_t set);
68
69static struct _s_x nat64cmds[] = {
70      { "create",	TOK_CREATE },
71      { "config",	TOK_CONFIG },
72      { "destroy",	TOK_DESTROY },
73      { "list",		TOK_LIST },
74      { "show",		TOK_LIST },
75      { "stats",	TOK_STATS },
76      { NULL, 0 }
77};
78
79static struct _s_x nat64statscmds[] = {
80      { "reset",	TOK_RESET },
81      { NULL, 0 }
82};
83
84/*
85 * This one handles all nat64clat-related commands
86 *	ipfw [set N] nat64clat NAME {create | config} ...
87 *	ipfw [set N] nat64clat NAME stats [reset]
88 *	ipfw [set N] nat64clat {NAME | all} destroy
89 *	ipfw [set N] nat64clat {NAME | all} {list | show}
90 */
91#define	nat64clat_check_name	table_check_name
92void
93ipfw_nat64clat_handler(int ac, char *av[])
94{
95	const char *name;
96	int tcmd;
97	uint8_t set;
98
99	if (co.use_set != 0)
100		set = co.use_set - 1;
101	else
102		set = 0;
103	ac--; av++;
104
105	NEED1("nat64clat needs instance name");
106	name = *av;
107	if (nat64clat_check_name(name) != 0) {
108		if (strcmp(name, "all") == 0)
109			name = NULL;
110		else
111			errx(EX_USAGE, "nat64clat instance name %s is invalid",
112			    name);
113	}
114	ac--; av++;
115	NEED1("nat64clat needs command");
116
117	tcmd = get_token(nat64cmds, *av, "nat64clat command");
118	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
119		errx(EX_USAGE, "nat64clat instance name required");
120	switch (tcmd) {
121	case TOK_CREATE:
122		ac--; av++;
123		nat64clat_create(name, set, ac, av);
124		break;
125	case TOK_CONFIG:
126		ac--; av++;
127		nat64clat_config(name, set, ac, av);
128		break;
129	case TOK_LIST:
130		nat64clat_foreach(nat64clat_show_cb, name, set, 1);
131		break;
132	case TOK_DESTROY:
133		if (name == NULL)
134			nat64clat_foreach(nat64clat_destroy_cb, NULL, set, 0);
135		else
136			nat64clat_destroy(name, set);
137		break;
138	case TOK_STATS:
139		ac--; av++;
140		if (ac == 0) {
141			nat64clat_stats(name, set);
142			break;
143		}
144		tcmd = get_token(nat64statscmds, *av, "stats command");
145		if (tcmd == TOK_RESET)
146			nat64clat_reset_stats(name, set);
147	}
148}
149
150
151static void
152nat64clat_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
153{
154
155	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
156	ntlv->head.length = sizeof(ipfw_obj_ntlv);
157	ntlv->idx = 1;
158	ntlv->set = set;
159	strlcpy(ntlv->name, name, sizeof(ntlv->name));
160}
161
162static struct _s_x nat64newcmds[] = {
163      { "plat_prefix",	TOK_PLAT_PREFIX },
164      { "clat_prefix",	TOK_CLAT_PREFIX },
165      { "log",		TOK_LOG },
166      { "-log",		TOK_LOGOFF },
167      { "allow_private", TOK_PRIVATE },
168      { "-allow_private", TOK_PRIVATEOFF },
169      { NULL, 0 }
170};
171
172/*
173 * Creates new nat64clat instance
174 * ipfw nat64clat <NAME> create clat_prefix <prefix> plat_prefix <prefix>
175 * Request: [ ipfw_obj_lheader ipfw_nat64clat_cfg ]
176 */
177#define	NAT64CLAT_HAS_CLAT_PREFIX	0x01
178#define	NAT64CLAT_HAS_PLAT_PREFIX	0x02
179static void
180nat64clat_create(const char *name, uint8_t set, int ac, char *av[])
181{
182	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nat64clat_cfg)];
183	ipfw_nat64clat_cfg *cfg;
184	ipfw_obj_lheader *olh;
185	int tcmd, flags;
186	char *p;
187	struct in6_addr prefix;
188	uint8_t plen;
189
190	memset(buf, 0, sizeof(buf));
191	olh = (ipfw_obj_lheader *)buf;
192	cfg = (ipfw_nat64clat_cfg *)(olh + 1);
193
194	/* Some reasonable defaults */
195	inet_pton(AF_INET6, "64:ff9b::", &cfg->plat_prefix);
196	cfg->plat_plen = 96;
197	cfg->set = set;
198	flags = NAT64CLAT_HAS_PLAT_PREFIX;
199	while (ac > 0) {
200		tcmd = get_token(nat64newcmds, *av, "option");
201		ac--; av++;
202
203		switch (tcmd) {
204		case TOK_PLAT_PREFIX:
205		case TOK_CLAT_PREFIX:
206			if (tcmd == TOK_PLAT_PREFIX) {
207				NEED1("IPv6 plat_prefix required");
208			} else {
209				NEED1("IPv6 clat_prefix required");
210			}
211
212			if ((p = strchr(*av, '/')) != NULL)
213				*p++ = '\0';
214			if (inet_pton(AF_INET6, *av, &prefix) != 1)
215				errx(EX_USAGE,
216				    "Bad prefix: %s", *av);
217			plen = strtol(p, NULL, 10);
218			if (ipfw_check_nat64prefix(&prefix, plen) != 0)
219				errx(EX_USAGE,
220				    "Bad prefix length: %s", p);
221			if (tcmd == TOK_PLAT_PREFIX) {
222				flags |= NAT64CLAT_HAS_PLAT_PREFIX;
223				cfg->plat_prefix = prefix;
224				cfg->plat_plen = plen;
225			} else {
226				flags |= NAT64CLAT_HAS_CLAT_PREFIX;
227				cfg->clat_prefix = prefix;
228				cfg->clat_plen = plen;
229			}
230			ac--; av++;
231			break;
232		case TOK_LOG:
233			cfg->flags |= NAT64_LOG;
234			break;
235		case TOK_LOGOFF:
236			cfg->flags &= ~NAT64_LOG;
237			break;
238		case TOK_PRIVATE:
239			cfg->flags |= NAT64_ALLOW_PRIVATE;
240			break;
241		case TOK_PRIVATEOFF:
242			cfg->flags &= ~NAT64_ALLOW_PRIVATE;
243			break;
244		}
245	}
246
247	/* Check validness */
248	if ((flags & NAT64CLAT_HAS_PLAT_PREFIX) != NAT64CLAT_HAS_PLAT_PREFIX)
249		errx(EX_USAGE, "plat_prefix required");
250	if ((flags & NAT64CLAT_HAS_CLAT_PREFIX) != NAT64CLAT_HAS_CLAT_PREFIX)
251		errx(EX_USAGE, "clat_prefix required");
252
253	olh->count = 1;
254	olh->objsize = sizeof(*cfg);
255	olh->size = sizeof(buf);
256	strlcpy(cfg->name, name, sizeof(cfg->name));
257	if (do_set3(IP_FW_NAT64CLAT_CREATE, &olh->opheader, sizeof(buf)) != 0)
258		err(EX_OSERR, "nat64clat instance creation failed");
259}
260
261/*
262 * Configures existing nat64clat instance
263 * ipfw nat64clat <NAME> config <options>
264 * Request: [ ipfw_obj_header ipfw_nat64clat_cfg ]
265 */
266static void
267nat64clat_config(const char *name, uint8_t set, int ac, char **av)
268{
269	char buf[sizeof(ipfw_obj_header) + sizeof(ipfw_nat64clat_cfg)];
270	ipfw_nat64clat_cfg *cfg;
271	ipfw_obj_header *oh;
272	char *opt;
273	char *p;
274	size_t sz;
275	int tcmd;
276	struct in6_addr prefix;
277	uint8_t plen;
278
279	if (ac == 0)
280		errx(EX_USAGE, "config options required");
281	memset(&buf, 0, sizeof(buf));
282	oh = (ipfw_obj_header *)buf;
283	cfg = (ipfw_nat64clat_cfg *)(oh + 1);
284	sz = sizeof(buf);
285
286	nat64clat_fill_ntlv(&oh->ntlv, name, set);
287	if (do_get3(IP_FW_NAT64CLAT_CONFIG, &oh->opheader, &sz) != 0)
288		err(EX_OSERR, "failed to get config for instance %s", name);
289
290	while (ac > 0) {
291		tcmd = get_token(nat64newcmds, *av, "option");
292		opt = *av;
293		ac--; av++;
294
295		switch (tcmd) {
296		case TOK_PLAT_PREFIX:
297		case TOK_CLAT_PREFIX:
298			if (tcmd == TOK_PLAT_PREFIX) {
299				NEED1("IPv6 plat_prefix required");
300			} else {
301				NEED1("IPv6 clat_prefix required");
302			}
303
304			if ((p = strchr(*av, '/')) != NULL)
305				*p++ = '\0';
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 */
347static void
348nat64clat_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 */
363static int
364nat64clat_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
384static void
385nat64clat_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 (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 */
422static void
423nat64clat_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
433static int
434nat64clat_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 (co.use_set != 0 && cfg->set != set)
442		return (ESRCH);
443
444	if (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
459static int
460nat64clat_destroy_cb(ipfw_nat64clat_cfg *cfg, const char *name, uint8_t set)
461{
462
463	if (co.use_set != 0 && cfg->set != set)
464		return (ESRCH);
465
466	nat64clat_destroy(cfg->name, cfg->set);
467	return (0);
468}
469
470
471/*
472 * Compare nat64clat instances names.
473 * Honor number comparison.
474 */
475static int
476nat64name_cmp(const void *a, const void *b)
477{
478	ipfw_nat64clat_cfg *ca, *cb;
479
480	ca = (ipfw_nat64clat_cfg *)a;
481	cb = (ipfw_nat64clat_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 nat64clat 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_nat64clat_cfg x N ]
496 */
497static int
498nat64clat_foreach(nat64clat_cb_t *f, const char *name, uint8_t set, int sort)
499{
500	ipfw_obj_lheader *olh;
501	ipfw_nat64clat_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_NAT64CLAT_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_nat64clat_cfg *)(olh + 1);
525		for (i = 0; i < olh->count; i++) {
526			error = f(cfg, name, set); /* Ignore errors for now */
527			cfg = (ipfw_nat64clat_cfg *)((caddr_t)cfg +
528			    olh->objsize);
529		}
530		free(olh);
531		break;
532	}
533	return (0);
534}
535
536