xref: /freebsd/sbin/ipfw/nptv6.c (revision 3a9fd8242b35884921dfc4e886f284a75870a536)
1  /*-
2   * Copyright (c) 2016 Yandex LLC
3   * Copyright (c) 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/param.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 <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_nptv6.h>
49  #include <arpa/inet.h>
50  
51  
52  typedef int (nptv6_cb_t)(ipfw_nptv6_cfg *i, const char *name, uint8_t set);
53  static int nptv6_foreach(nptv6_cb_t *f, const char *name, uint8_t set,
54      int sort);
55  
56  static void nptv6_create(const char *name, uint8_t set, int ac, char **av);
57  static void nptv6_destroy(const char *name, uint8_t set);
58  static void nptv6_stats(const char *name, uint8_t set);
59  static void nptv6_reset_stats(const char *name, uint8_t set);
60  static int nptv6_show_cb(ipfw_nptv6_cfg *cfg, const char *name, uint8_t set);
61  static int nptv6_destroy_cb(ipfw_nptv6_cfg *cfg, const char *name, uint8_t set);
62  
63  static struct _s_x nptv6cmds[] = {
64        { "create",	TOK_CREATE },
65        { "destroy",	TOK_DESTROY },
66        { "list",		TOK_LIST },
67        { "show",		TOK_LIST },
68        { "stats",	TOK_STATS },
69        { NULL, 0 }
70  };
71  
72  static struct _s_x nptv6statscmds[] = {
73        { "reset",	TOK_RESET },
74        { NULL, 0 }
75  };
76  
77  /*
78   * This one handles all NPTv6-related commands
79   *	ipfw [set N] nptv6 NAME {create | config} ...
80   *	ipfw [set N] nptv6 NAME stats [reset]
81   *	ipfw [set N] nptv6 {NAME | all} destroy
82   *	ipfw [set N] nptv6 {NAME | all} {list | show}
83   */
84  #define	nptv6_check_name	table_check_name
85  void
86  ipfw_nptv6_handler(int ac, char *av[])
87  {
88  	const char *name;
89  	int tcmd;
90  	uint8_t set;
91  
92  	if (g_co.use_set != 0)
93  		set = g_co.use_set - 1;
94  	else
95  		set = 0;
96  	ac--; av++;
97  
98  	NEED1("nptv6 needs instance name");
99  	name = *av;
100  	if (nptv6_check_name(name) != 0) {
101  		if (strcmp(name, "all") == 0) {
102  			name = NULL;
103  		} else
104  			errx(EX_USAGE, "nptv6 instance name %s is invalid",
105  			    name);
106  	}
107  	ac--; av++;
108  	NEED1("nptv6 needs command");
109  
110  	tcmd = get_token(nptv6cmds, *av, "nptv6 command");
111  	if (name == NULL && tcmd != TOK_DESTROY && tcmd != TOK_LIST)
112  		errx(EX_USAGE, "nptv6 instance name required");
113  	switch (tcmd) {
114  	case TOK_CREATE:
115  		ac--; av++;
116  		nptv6_create(name, set, ac, av);
117  		break;
118  	case TOK_LIST:
119  		nptv6_foreach(nptv6_show_cb, name, set, 1);
120  		break;
121  	case TOK_DESTROY:
122  		if (name == NULL)
123  			nptv6_foreach(nptv6_destroy_cb, NULL, set, 0);
124  		else
125  			nptv6_destroy(name, set);
126  		break;
127  	case TOK_STATS:
128  		ac--; av++;
129  		if (ac == 0) {
130  			nptv6_stats(name, set);
131  			break;
132  		}
133  		tcmd = get_token(nptv6statscmds, *av, "stats command");
134  		if (tcmd == TOK_RESET)
135  			nptv6_reset_stats(name, set);
136  	}
137  }
138  
139  
140  static void
141  nptv6_fill_ntlv(ipfw_obj_ntlv *ntlv, const char *name, uint8_t set)
142  {
143  
144  	ntlv->head.type = IPFW_TLV_EACTION_NAME(1); /* it doesn't matter */
145  	ntlv->head.length = sizeof(ipfw_obj_ntlv);
146  	ntlv->idx = 1;
147  	ntlv->set = set;
148  	strlcpy(ntlv->name, name, sizeof(ntlv->name));
149  }
150  
151  static struct _s_x nptv6newcmds[] = {
152        { "int_prefix",	TOK_INTPREFIX },
153        { "ext_prefix",	TOK_EXTPREFIX },
154        { "prefixlen",	TOK_PREFIXLEN },
155        { "ext_if",	TOK_EXTIF },
156        { NULL, 0 }
157  };
158  
159  
160  static void
161  nptv6_parse_prefix(const char *arg, struct in6_addr *prefix, int *len)
162  {
163  	char *p, *l;
164  
165  	p = strdup(arg);
166  	if (p == NULL)
167  		err(EX_OSERR, NULL);
168  	if ((l = strchr(p, '/')) != NULL)
169  		*l++ = '\0';
170  	if (inet_pton(AF_INET6, p, prefix) != 1)
171  		errx(EX_USAGE, "Bad prefix: %s", p);
172  	if (l != NULL) {
173  		*len = (int)strtol(l, &l, 10);
174  		if (*l != '\0' || *len <= 0 || *len > 64)
175  			errx(EX_USAGE, "Bad prefix length: %s", arg);
176  	} else
177  		*len = 0;
178  	free(p);
179  }
180  /*
181   * Creates new nptv6 instance
182   * ipfw nptv6 <NAME> create int_prefix <prefix> ext_prefix <prefix>
183   * Request: [ ipfw_obj_lheader ipfw_nptv6_cfg ]
184   */
185  #define	NPTV6_HAS_INTPREFIX	0x01
186  #define	NPTV6_HAS_EXTPREFIX	0x02
187  #define	NPTV6_HAS_PREFIXLEN	0x04
188  static void
189  nptv6_create(const char *name, uint8_t set, int ac, char *av[])
190  {
191  	char buf[sizeof(ipfw_obj_lheader) + sizeof(ipfw_nptv6_cfg)];
192  	struct in6_addr mask;
193  	ipfw_nptv6_cfg *cfg;
194  	ipfw_obj_lheader *olh;
195  	int tcmd, flags, plen;
196  	char *p;
197  
198  	plen = 0;
199  	memset(buf, 0, sizeof(buf));
200  	olh = (ipfw_obj_lheader *)buf;
201  	cfg = (ipfw_nptv6_cfg *)(olh + 1);
202  	cfg->set = set;
203  	flags = 0;
204  	while (ac > 0) {
205  		tcmd = get_token(nptv6newcmds, *av, "option");
206  		ac--; av++;
207  
208  		switch (tcmd) {
209  		case TOK_INTPREFIX:
210  			NEED1("IPv6 prefix required");
211  			nptv6_parse_prefix(*av, &cfg->internal, &plen);
212  			flags |= NPTV6_HAS_INTPREFIX;
213  			if (plen > 0)
214  				goto check_prefix;
215  			ac--; av++;
216  			break;
217  		case TOK_EXTPREFIX:
218  			if (flags & NPTV6_HAS_EXTPREFIX)
219  				errx(EX_USAGE,
220  				    "Only one ext_prefix or ext_if allowed");
221  			NEED1("IPv6 prefix required");
222  			nptv6_parse_prefix(*av, &cfg->external, &plen);
223  			flags |= NPTV6_HAS_EXTPREFIX;
224  			if (plen > 0)
225  				goto check_prefix;
226  			ac--; av++;
227  			break;
228  		case TOK_EXTIF:
229  			if (flags & NPTV6_HAS_EXTPREFIX)
230  				errx(EX_USAGE,
231  				    "Only one ext_prefix or ext_if allowed");
232  			NEED1("Interface name required");
233  			if (strlen(*av) >= sizeof(cfg->if_name))
234  				errx(EX_USAGE, "Invalid interface name");
235  			flags |= NPTV6_HAS_EXTPREFIX;
236  			cfg->flags |= NPTV6_DYNAMIC_PREFIX;
237  			strncpy(cfg->if_name, *av, sizeof(cfg->if_name));
238  			ac--; av++;
239  			break;
240  		case TOK_PREFIXLEN:
241  			NEED1("IPv6 prefix length required");
242  			plen = strtol(*av, &p, 10);
243  check_prefix:
244  			if (*p != '\0' || plen < 8 || plen > 64)
245  				errx(EX_USAGE, "wrong prefix length: %s", *av);
246  			/* RFC 6296 Sec. 3.1 */
247  			if (cfg->plen > 0 && cfg->plen != plen) {
248  				warnx("Prefix length mismatch (%d vs %d).  "
249  				    "It was extended up to %d",
250  				    cfg->plen, plen, MAX(plen, cfg->plen));
251  				plen = MAX(plen, cfg->plen);
252  			}
253  			cfg->plen = plen;
254  			flags |= NPTV6_HAS_PREFIXLEN;
255  			ac--; av++;
256  			break;
257  		}
258  	}
259  
260  	/* Check validness */
261  	if ((flags & NPTV6_HAS_INTPREFIX) != NPTV6_HAS_INTPREFIX)
262  		errx(EX_USAGE, "int_prefix required");
263  	if ((flags & NPTV6_HAS_EXTPREFIX) != NPTV6_HAS_EXTPREFIX)
264  		errx(EX_USAGE, "ext_prefix or ext_if required");
265  	if ((flags & NPTV6_HAS_PREFIXLEN) != NPTV6_HAS_PREFIXLEN)
266  		errx(EX_USAGE, "prefixlen required");
267  
268  	n2mask(&mask, cfg->plen);
269  	APPLY_MASK(&cfg->internal, &mask);
270  	if ((cfg->flags & NPTV6_DYNAMIC_PREFIX) == 0)
271  		APPLY_MASK(&cfg->external, &mask);
272  
273  	olh->count = 1;
274  	olh->objsize = sizeof(*cfg);
275  	olh->size = sizeof(buf);
276  	strlcpy(cfg->name, name, sizeof(cfg->name));
277  	if (do_set3(IP_FW_NPTV6_CREATE, &olh->opheader, sizeof(buf)) != 0)
278  		err(EX_OSERR, "nptv6 instance creation failed");
279  }
280  
281  /*
282   * Destroys NPTv6 instance.
283   * Request: [ ipfw_obj_header ]
284   */
285  static void
286  nptv6_destroy(const char *name, uint8_t set)
287  {
288  	ipfw_obj_header oh;
289  
290  	memset(&oh, 0, sizeof(oh));
291  	nptv6_fill_ntlv(&oh.ntlv, name, set);
292  	if (do_set3(IP_FW_NPTV6_DESTROY, &oh.opheader, sizeof(oh)) != 0)
293  		err(EX_OSERR, "failed to destroy nat instance %s", name);
294  }
295  
296  /*
297   * Get NPTv6 instance statistics.
298   * Request: [ ipfw_obj_header ]
299   * Reply: [ ipfw_obj_header ipfw_obj_ctlv [ uint64_t x N ] ]
300   */
301  static int
302  nptv6_get_stats(const char *name, uint8_t set, struct ipfw_nptv6_stats *stats)
303  {
304  	ipfw_obj_header *oh;
305  	ipfw_obj_ctlv *oc;
306  	size_t sz;
307  
308  	sz = sizeof(*oh) + sizeof(*oc) + sizeof(*stats);
309  	oh = calloc(1, sz);
310  	nptv6_fill_ntlv(&oh->ntlv, name, set);
311  	if (do_get3(IP_FW_NPTV6_STATS, &oh->opheader, &sz) == 0) {
312  		oc = (ipfw_obj_ctlv *)(oh + 1);
313  		memcpy(stats, oc + 1, sizeof(*stats));
314  		free(oh);
315  		return (0);
316  	}
317  	free(oh);
318  	return (-1);
319  }
320  
321  static void
322  nptv6_stats(const char *name, uint8_t set)
323  {
324  	struct ipfw_nptv6_stats stats;
325  
326  	if (nptv6_get_stats(name, set, &stats) != 0)
327  		err(EX_OSERR, "Error retrieving stats");
328  
329  	if (g_co.use_set != 0 || set != 0)
330  		printf("set %u ", set);
331  	printf("nptv6 %s\n", name);
332  	printf("\t%ju packets translated (internal to external)\n",
333  	    (uintmax_t)stats.in2ex);
334  	printf("\t%ju packets translated (external to internal)\n",
335  	    (uintmax_t)stats.ex2in);
336  	printf("\t%ju packets dropped due to some error\n",
337  	    (uintmax_t)stats.dropped);
338  }
339  
340  /*
341   * Reset NPTv6 instance statistics specified by @oh->ntlv.
342   * Request: [ ipfw_obj_header ]
343   */
344  static void
345  nptv6_reset_stats(const char *name, uint8_t set)
346  {
347  	ipfw_obj_header oh;
348  
349  	memset(&oh, 0, sizeof(oh));
350  	nptv6_fill_ntlv(&oh.ntlv, name, set);
351  	if (do_set3(IP_FW_NPTV6_RESET_STATS, &oh.opheader, sizeof(oh)) != 0)
352  		err(EX_OSERR, "failed to reset stats for instance %s", name);
353  }
354  
355  static int
356  nptv6_show_cb(ipfw_nptv6_cfg *cfg, const char *name, uint8_t set)
357  {
358  	char abuf[INET6_ADDRSTRLEN];
359  
360  	if (name != NULL && strcmp(cfg->name, name) != 0)
361  		return (ESRCH);
362  
363  	if (g_co.use_set != 0 && cfg->set != set)
364  		return (ESRCH);
365  
366  	if (g_co.use_set != 0 || cfg->set != 0)
367  		printf("set %u ", cfg->set);
368  	inet_ntop(AF_INET6, &cfg->internal, abuf, sizeof(abuf));
369  	printf("nptv6 %s int_prefix %s ", cfg->name, abuf);
370  	if (cfg->flags & NPTV6_DYNAMIC_PREFIX)
371  		printf("ext_if %s ", cfg->if_name);
372  	else {
373  		inet_ntop(AF_INET6, &cfg->external, abuf, sizeof(abuf));
374  		printf("ext_prefix %s ", abuf);
375  	}
376  	printf("prefixlen %u\n", cfg->plen);
377  	return (0);
378  }
379  
380  static int
381  nptv6_destroy_cb(ipfw_nptv6_cfg *cfg, const char *name __unused, uint8_t set)
382  {
383  
384  	if (g_co.use_set != 0 && cfg->set != set)
385  		return (ESRCH);
386  
387  	nptv6_destroy(cfg->name, cfg->set);
388  	return (0);
389  }
390  
391  
392  /*
393   * Compare NPTv6 instances names.
394   * Honor number comparison.
395   */
396  static int
397  nptv6name_cmp(const void *a, const void *b)
398  {
399  	const ipfw_nptv6_cfg *ca, *cb;
400  
401  	ca = (const ipfw_nptv6_cfg *)a;
402  	cb = (const ipfw_nptv6_cfg *)b;
403  
404  	if (ca->set > cb->set)
405  		return (1);
406  	else if (ca->set < cb->set)
407  		return (-1);
408  	return (stringnum_cmp(ca->name, cb->name));
409  }
410  
411  /*
412   * Retrieves NPTv6 instance list from kernel,
413   * Request: [ ipfw_obj_lheader ]
414   * Reply: [ ipfw_obj_lheader ipfw_nptv6_cfg x N ]
415   */
416  static int
417  nptv6_foreach(nptv6_cb_t *f, const char *name, uint8_t set, int sort)
418  {
419  	ipfw_obj_lheader *olh;
420  	ipfw_nptv6_cfg *cfg;
421  	size_t sz;
422  	uint32_t i;
423  	int error;
424  
425  	/* Start with reasonable default */
426  	sz = sizeof(*olh) + 16 * sizeof(*cfg);
427  	for (;;) {
428  		if ((olh = calloc(1, sz)) == NULL)
429  			return (ENOMEM);
430  
431  		olh->size = sz;
432  		if (do_get3(IP_FW_NPTV6_LIST, &olh->opheader, &sz) != 0) {
433  			sz = olh->size;
434  			free(olh);
435  			if (errno != ENOMEM)
436  				return (errno);
437  			continue;
438  		}
439  
440  		if (sort != 0)
441  			qsort(olh + 1, olh->count, olh->objsize, nptv6name_cmp);
442  
443  		cfg = (ipfw_nptv6_cfg *)(olh + 1);
444  		for (i = 0; i < olh->count; i++) {
445  			error = f(cfg, name, set);
446  			cfg = (ipfw_nptv6_cfg *)((caddr_t)cfg + olh->objsize);
447  		}
448  		free(olh);
449  		break;
450  	}
451  	return (0);
452  }
453  
454