xref: /freebsd/sbin/ipf/ipnat/ipnat.c (revision e0c4386e) 
1 
2 /*
3  * Copyright (C) 2012 by Darren Reed.
4  *
5  * See the IPFILTER.LICENCE file for details on licencing.
6  *
7  * Added redirect stuff and a variety of bug fixes. (mcn@EnGarde.com)
8  */
9 #include <stdio.h>
10 #include <string.h>
11 #include <fcntl.h>
12 #include <errno.h>
13 #include <sys/types.h>
14 #if !defined(__SVR4)
15 #include <strings.h>
16 #else
17 #include <sys/byteorder.h>
18 #endif
19 #include <sys/time.h>
20 #include <sys/param.h>
21 #include <stdlib.h>
22 #include <unistd.h>
23 #include <stddef.h>
24 #include <sys/file.h>
25 #define _KERNEL
26 #include <sys/uio.h>
27 #undef _KERNEL
28 #include <sys/socket.h>
29 #include <sys/ioctl.h>
30 #if defined(sun) && defined(__SVR4)
31 # include <sys/ioccom.h>
32 # include <sys/sysmacros.h>
33 #endif
34 #include <netinet/in.h>
35 #include <netinet/in_systm.h>
36 #include <netinet/ip.h>
37 #include <netinet/tcp.h>
38 #include <net/if.h>
39 #include <netdb.h>
40 #include <arpa/nameser.h>
41 #include <arpa/inet.h>
42 #include <resolv.h>
43 #include <ctype.h>
44 # include <nlist.h>
45 #include "ipf.h"
46 #include "netinet/ipl.h"
47 #include "kmem.h"
48 
49 
50 # define	STRERROR(x)	strerror(x)
51 
52 
53 
54 #if	SOLARIS
55 #define	bzero(a,b)	memset(a,0,b)
56 #endif
57 int	use_inet6 = 0;
58 
59 extern	char	*optarg;
60 
61 void	dostats(int, natstat_t *, int, int, int *);
62 void	dotable(natstat_t *, int, int, int, char *);
63 void	flushtable(int, int, int *);
64 void	usage(char *);
65 int	main(int, char*[]);
66 void	showhostmap(natstat_t *nsp);
67 void	natstat_dead(natstat_t *, char *);
68 void	dostats_live(int, natstat_t *, int, int *);
69 void	showhostmap_dead(natstat_t *);
70 void	showhostmap_live(int, natstat_t *);
71 void	dostats_dead(natstat_t *, int, int *);
72 int	nat_matcharray(nat_t *, int *);
73 
74 int		opts;
75 int		nohdrfields = 0;
76 wordtab_t	*nat_fields = NULL;
77 
78 void
79 usage(char *name)
80 {
81 	fprintf(stderr, "Usage: %s [-CFhlnrRsv] [-f filename]\n", name);
82 	exit(1);
83 }
84 
85 
86 int
87 main(int argc, char *argv[])
88 {
89 	int fd, c, mode, *natfilter;
90 	char *file, *core, *kernel;
91 	natstat_t ns, *nsp;
92 	ipfobj_t obj;
93 
94 	fd = -1;
95 	opts = 0;
96 	nsp = &ns;
97 	file = NULL;
98 	core = NULL;
99 	kernel = NULL;
100 	mode = O_RDWR;
101 	natfilter = NULL;
102 
103 	assigndefined(getenv("IPNAT_PREDEFINED"));
104 
105 	while ((c = getopt(argc, argv, "CdFf:hlm:M:N:nO:prRsv")) != -1)
106 		switch (c)
107 		{
108 		case 'C' :
109 			opts |= OPT_CLEAR;
110 			break;
111 		case 'd' :
112 			opts |= OPT_DEBUG;
113 			break;
114 		case 'f' :
115 			file = optarg;
116 			break;
117 		case 'F' :
118 			opts |= OPT_FLUSH;
119 			break;
120 		case 'h' :
121 			opts |=OPT_HITS;
122 			break;
123 		case 'l' :
124 			opts |= OPT_LIST;
125 			mode = O_RDONLY;
126 			break;
127 		case 'm' :
128 			natfilter = parseipfexpr(optarg, NULL);
129 			break;
130 		case 'M' :
131 			core = optarg;
132 			break;
133 		case 'N' :
134 			kernel = optarg;
135 			break;
136 		case 'n' :
137 			opts |= OPT_DONOTHING|OPT_DONTOPEN;
138 			mode = O_RDONLY;
139 			break;
140 		case 'O' :
141 			nat_fields = parsefields(natfields, optarg);
142 			break;
143 		case 'p' :
144 			opts |= OPT_PURGE;
145 			break;
146 		case 'R' :
147 			opts |= OPT_NORESOLVE;
148 			break;
149 		case 'r' :
150 			opts |= OPT_REMOVE;
151 			break;
152 		case 's' :
153 			opts |= OPT_STAT;
154 			mode = O_RDONLY;
155 			break;
156 		case 'v' :
157 			opts |= OPT_VERBOSE;
158 			break;
159 		default :
160 			usage(argv[0]);
161 		}
162 
163 	if (((opts & OPT_PURGE) != 0) && ((opts & OPT_REMOVE) == 0)) {
164 		(void) fprintf(stderr, "%s: -p must be used with -r\n",
165 			       argv[0]);
166 		exit(1);
167 	}
168 
169 	initparse();
170 
171 	if ((kernel != NULL) || (core != NULL)) {
172 		(void) setgid(getgid());
173 		(void) setuid(getuid());
174 	}
175 
176 	if (!(opts & OPT_DONOTHING)) {
177 		if (((fd = open(IPNAT_NAME, mode)) == -1) &&
178 		    ((fd = open(IPNAT_NAME, O_RDONLY)) == -1)) {
179 			(void) fprintf(stderr, "%s: open: %s\n", IPNAT_NAME,
180 				STRERROR(errno));
181 			exit(1);
182 		}
183 	}
184 
185 	bzero((char *)&ns, sizeof(ns));
186 
187 	if ((opts & OPT_DONOTHING) == 0) {
188 		if (checkrev(IPL_NAME) == -1) {
189 			fprintf(stderr, "User/kernel version check failed\n");
190 			exit(1);
191 		}
192 	}
193 
194 	if (!(opts & OPT_DONOTHING) && (kernel == NULL) && (core == NULL)) {
195 		bzero((char *)&obj, sizeof(obj));
196 		obj.ipfo_rev = IPFILTER_VERSION;
197 		obj.ipfo_type = IPFOBJ_NATSTAT;
198 		obj.ipfo_size = sizeof(*nsp);
199 		obj.ipfo_ptr = (void *)nsp;
200 		if (ioctl(fd, SIOCGNATS, &obj) == -1) {
201 			ipferror(fd, "ioctl(SIOCGNATS)");
202 			exit(1);
203 		}
204 		(void) setgid(getgid());
205 		(void) setuid(getuid());
206 	} else if ((kernel != NULL) || (core != NULL)) {
207 		if (openkmem(kernel, core) == -1)
208 			exit(1);
209 
210 		natstat_dead(nsp, kernel);
211 		if (opts & (OPT_LIST|OPT_STAT))
212 			dostats(fd, nsp, opts, 0, natfilter);
213 		exit(0);
214 	}
215 
216 	if (opts & (OPT_FLUSH|OPT_CLEAR))
217 		flushtable(fd, opts, natfilter);
218 	if (file) {
219 		return (ipnat_parsefile(fd, ipnat_addrule, ioctl, file));
220 	}
221 	if (opts & (OPT_LIST|OPT_STAT))
222 		dostats(fd, nsp, opts, 1, natfilter);
223 	return (0);
224 }
225 
226 
227 /*
228  * Read NAT statistic information in using a symbol table and memory file
229  * rather than doing ioctl's.
230  */
231 void
232 natstat_dead(natstat_t *nsp, char *kernel)
233 {
234 	struct nlist nat_nlist[10] = {
235 		{ "nat_table" },		/* 0 */
236 		{ "nat_list" },
237 		{ "maptable" },
238 		{ "ipf_nattable_sz" },
239 		{ "ipf_natrules_sz" },
240 		{ "ipf_rdrrules_sz" },		/* 5 */
241 		{ "ipf_hostmap_sz" },
242 		{ "nat_instances" },
243 		{ NULL }
244 	};
245 	void *tables[2];
246 
247 	if (nlist(kernel, nat_nlist) == -1) {
248 		fprintf(stderr, "nlist error\n");
249 		return;
250 	}
251 
252 	/*
253 	 * Normally the ioctl copies all of these values into the structure
254 	 * for us, before returning it to userland, so here we must copy each
255 	 * one in individually.
256 	 */
257 	kmemcpy((char *)&tables, nat_nlist[0].n_value, sizeof(tables));
258 	nsp->ns_side[0].ns_table = tables[0];
259 	nsp->ns_side[1].ns_table = tables[1];
260 
261 	kmemcpy((char *)&nsp->ns_list, nat_nlist[1].n_value,
262 		sizeof(nsp->ns_list));
263 	kmemcpy((char *)&nsp->ns_maptable, nat_nlist[2].n_value,
264 		sizeof(nsp->ns_maptable));
265 	kmemcpy((char *)&nsp->ns_nattab_sz, nat_nlist[3].n_value,
266 		sizeof(nsp->ns_nattab_sz));
267 	kmemcpy((char *)&nsp->ns_rultab_sz, nat_nlist[4].n_value,
268 		sizeof(nsp->ns_rultab_sz));
269 	kmemcpy((char *)&nsp->ns_rdrtab_sz, nat_nlist[5].n_value,
270 		sizeof(nsp->ns_rdrtab_sz));
271 	kmemcpy((char *)&nsp->ns_hostmap_sz, nat_nlist[6].n_value,
272 		sizeof(nsp->ns_hostmap_sz));
273 	kmemcpy((char *)&nsp->ns_instances, nat_nlist[7].n_value,
274 		sizeof(nsp->ns_instances));
275 }
276 
277 
278 /*
279  * Issue an ioctl to flush either the NAT rules table or the active mapping
280  * table or both.
281  */
282 void
283 flushtable(int fd, int opts, int *match)
284 {
285 	int n = 0;
286 
287 	if (opts & OPT_FLUSH) {
288 		n = 0;
289 		if (!(opts & OPT_DONOTHING)) {
290 			if (match != NULL) {
291 				ipfobj_t obj;
292 
293 				obj.ipfo_rev = IPFILTER_VERSION;
294 				obj.ipfo_size = match[0] * sizeof(int);
295 				obj.ipfo_type = IPFOBJ_IPFEXPR;
296 				obj.ipfo_ptr = match;
297 				if (ioctl(fd, SIOCMATCHFLUSH, &obj) == -1) {
298 					ipferror(fd, "ioctl(SIOCMATCHFLUSH)");
299 					n = -1;
300 				} else {
301 					n = obj.ipfo_retval;
302 				}
303 			} else if (ioctl(fd, SIOCIPFFL, &n) == -1) {
304 				ipferror(fd, "ioctl(SIOCIPFFL)");
305 				n = -1;
306 			}
307 		}
308 		if (n >= 0)
309 			printf("%d entries flushed from NAT table\n", n);
310 	}
311 
312 	if (opts & OPT_CLEAR) {
313 		n = 1;
314 		if (!(opts & OPT_DONOTHING) && ioctl(fd, SIOCIPFFL, &n) == -1)
315 			ipferror(fd, "ioctl(SIOCCNATL)");
316 		else
317 			printf("%d entries flushed from NAT list\n", n);
318 	}
319 }
320 
321 
322 /*
323  * Display NAT statistics.
324  */
325 void
326 dostats_dead(natstat_t *nsp, int opts, int *filter)
327 {
328 	nat_t *np, nat;
329 	ipnat_t	ipn;
330 	int i;
331 
332 	if (nat_fields == NULL) {
333 		printf("List of active MAP/Redirect filters:\n");
334 		while (nsp->ns_list) {
335 			if (kmemcpy((char *)&ipn, (long)nsp->ns_list,
336 				    sizeof(ipn))) {
337 				perror("kmemcpy");
338 				break;
339 			}
340 			if (opts & OPT_HITS)
341 				printf("%lu ", ipn.in_hits);
342 			printnat(&ipn, opts & (OPT_DEBUG|OPT_VERBOSE));
343 			nsp->ns_list = ipn.in_next;
344 		}
345 	}
346 
347 	if (nat_fields == NULL) {
348 		printf("\nList of active sessions:\n");
349 
350 	} else if (nohdrfields == 0) {
351 		for (i = 0; nat_fields[i].w_value != 0; i++) {
352 			printfieldhdr(natfields, nat_fields + i);
353 			if (nat_fields[i + 1].w_value != 0)
354 				printf("\t");
355 		}
356 		printf("\n");
357 	}
358 
359 	for (np = nsp->ns_instances; np; np = nat.nat_next) {
360 		if (kmemcpy((char *)&nat, (long)np, sizeof(nat)))
361 			break;
362 		if ((filter != NULL) && (nat_matcharray(&nat, filter) == 0))
363 			continue;
364 		if (nat_fields != NULL) {
365 			for (i = 0; nat_fields[i].w_value != 0; i++) {
366 				printnatfield(&nat, nat_fields[i].w_value);
367 				if (nat_fields[i + 1].w_value != 0)
368 					printf("\t");
369 			}
370 			printf("\n");
371 		} else {
372 			printactivenat(&nat, opts, nsp->ns_ticks);
373 			if (nat.nat_aps) {
374 				int proto;
375 
376 				if (nat.nat_dir & NAT_OUTBOUND)
377 					proto = nat.nat_pr[1];
378 				else
379 					proto = nat.nat_pr[0];
380 				printaps(nat.nat_aps, opts, proto);
381 			}
382 		}
383 	}
384 
385 	if (opts & OPT_VERBOSE)
386 		showhostmap_dead(nsp);
387 }
388 
389 
390 void
391 dotable(natstat_t *nsp, int fd, int alive, int which, char *side)
392 {
393 	int sz, i, used, maxlen, minlen, totallen;
394 	ipftable_t table;
395 	u_int *buckets;
396 	ipfobj_t obj;
397 
398 	sz = sizeof(*buckets) * nsp->ns_nattab_sz;
399 	buckets = (u_int *)malloc(sz);
400 	if (buckets == NULL) {
401 		fprintf(stderr,
402 			"cannot allocate memory (%d) for buckets\n", sz);
403 		return;
404 	}
405 
406 	obj.ipfo_rev = IPFILTER_VERSION;
407 	obj.ipfo_type = IPFOBJ_GTABLE;
408 	obj.ipfo_size = sizeof(table);
409 	obj.ipfo_ptr = &table;
410 
411 	if (which == 0) {
412 		table.ita_type = IPFTABLE_BUCKETS_NATIN;
413 	} else if (which == 1) {
414 		table.ita_type = IPFTABLE_BUCKETS_NATOUT;
415 	}
416 	table.ita_table = buckets;
417 
418 	if (alive) {
419 		if (ioctl(fd, SIOCGTABL, &obj) != 0) {
420 			ipferror(fd, "SIOCFTABL");
421 			free(buckets);
422 			return;
423 		}
424 	} else {
425 		if (kmemcpy((char *)buckets, (u_long)nsp->ns_nattab_sz, sz)) {
426 			free(buckets);
427 			return;
428 		}
429 	}
430 
431 	minlen = nsp->ns_side[which].ns_inuse;
432 	totallen = 0;
433 	maxlen = 0;
434 	used = 0;
435 
436 	for (i = 0; i < nsp->ns_nattab_sz; i++) {
437 		if (buckets[i] > maxlen)
438 			maxlen = buckets[i];
439 		if (buckets[i] < minlen)
440 			minlen = buckets[i];
441 		if (buckets[i] != 0)
442 			used++;
443 		totallen += buckets[i];
444 	}
445 
446 	printf("%d%%\thash efficiency %s\n",
447 	       totallen ? used * 100 / totallen : 0, side);
448 	printf("%2.2f%%\tbucket usage %s\n",
449 	       ((float)used / nsp->ns_nattab_sz) * 100.0, side);
450 	printf("%d\tminimal length %s\n", minlen, side);
451 	printf("%d\tmaximal length %s\n", maxlen, side);
452 	printf("%.3f\taverage length %s\n",
453 	       used ? ((float)totallen / used) : 0.0, side);
454 
455 	free(buckets);
456 }
457 
458 
459 void
460 dostats(int fd, natstat_t *nsp, int opts, int alive, int *filter)
461 {
462 	/*
463 	 * Show statistics ?
464 	 */
465 	if (opts & OPT_STAT) {
466 		printnatside("in", &nsp->ns_side[0]);
467 		dotable(nsp, fd, alive, 0, "in");
468 
469 		printnatside("out", &nsp->ns_side[1]);
470 		dotable(nsp, fd, alive, 1, "out");
471 
472 		printf("%lu\tlog successes\n", nsp->ns_side[0].ns_log);
473 		printf("%lu\tlog failures\n", nsp->ns_side[1].ns_log);
474 		printf("%lu\tadded in\n%lu\tadded out\n",
475 			nsp->ns_side[0].ns_added,
476 			nsp->ns_side[1].ns_added);
477 		printf("%u\tactive\n", nsp->ns_active);
478 		printf("%lu\ttransparent adds\n", nsp->ns_addtrpnt);
479 		printf("%lu\tdivert build\n", nsp->ns_divert_build);
480 		printf("%lu\texpired\n", nsp->ns_expire);
481 		printf("%lu\tflush all\n", nsp->ns_flush_all);
482 		printf("%lu\tflush closing\n", nsp->ns_flush_closing);
483 		printf("%lu\tflush queue\n", nsp->ns_flush_queue);
484 		printf("%lu\tflush state\n", nsp->ns_flush_state);
485 		printf("%lu\tflush timeout\n", nsp->ns_flush_timeout);
486 		printf("%lu\thostmap new\n", nsp->ns_hm_new);
487 		printf("%lu\thostmap fails\n", nsp->ns_hm_newfail);
488 		printf("%lu\thostmap add\n", nsp->ns_hm_addref);
489 		printf("%lu\thostmap NULL rule\n", nsp->ns_hm_nullnp);
490 		printf("%lu\tlog ok\n", nsp->ns_log_ok);
491 		printf("%lu\tlog fail\n", nsp->ns_log_fail);
492 		printf("%u\torphan count\n", nsp->ns_orphans);
493 		printf("%u\trule count\n", nsp->ns_rules);
494 		printf("%u\tmap rules\n", nsp->ns_rules_map);
495 		printf("%u\trdr rules\n", nsp->ns_rules_rdr);
496 		printf("%u\twilds\n", nsp->ns_wilds);
497 		if (opts & OPT_VERBOSE)
498 			printf("list %p\n", nsp->ns_list);
499 	}
500 
501 	if (opts & OPT_LIST) {
502 		if (alive)
503 			dostats_live(fd, nsp, opts, filter);
504 		else
505 			dostats_dead(nsp, opts, filter);
506 	}
507 }
508 
509 
510 /*
511  * Display NAT statistics.
512  */
513 void
514 dostats_live(int fd, natstat_t *nsp, int opts, int *filter)
515 {
516 	ipfgeniter_t iter;
517 	char buffer[2000];
518 	ipfobj_t obj;
519 	ipnat_t	*ipn;
520 	nat_t nat;
521 	int i;
522 
523 	bzero((char *)&obj, sizeof(obj));
524 	obj.ipfo_rev = IPFILTER_VERSION;
525 	obj.ipfo_type = IPFOBJ_GENITER;
526 	obj.ipfo_size = sizeof(iter);
527 	obj.ipfo_ptr = &iter;
528 
529 	iter.igi_type = IPFGENITER_IPNAT;
530 	iter.igi_nitems = 1;
531 	iter.igi_data = buffer;
532 	ipn = (ipnat_t *)buffer;
533 
534 	/*
535 	 * Show list of NAT rules and NAT sessions ?
536 	 */
537 	if (nat_fields == NULL) {
538 		printf("List of active MAP/Redirect filters:\n");
539 		while (nsp->ns_list) {
540 			if (ioctl(fd, SIOCGENITER, &obj) == -1)
541 				break;
542 			if (opts & OPT_HITS)
543 				printf("%lu ", ipn->in_hits);
544 			printnat(ipn, opts & (OPT_DEBUG|OPT_VERBOSE));
545 			nsp->ns_list = ipn->in_next;
546 		}
547 	}
548 
549 	if (nat_fields == NULL) {
550 		printf("\nList of active sessions:\n");
551 
552 	} else if (nohdrfields == 0) {
553 		for (i = 0; nat_fields[i].w_value != 0; i++) {
554 			printfieldhdr(natfields, nat_fields + i);
555 			if (nat_fields[i + 1].w_value != 0)
556 				printf("\t");
557 		}
558 		printf("\n");
559 	}
560 
561 	i = IPFGENITER_IPNAT;
562 	(void) ioctl(fd,SIOCIPFDELTOK, &i);
563 
564 
565 	iter.igi_type = IPFGENITER_NAT;
566 	iter.igi_nitems = 1;
567 	iter.igi_data = &nat;
568 
569 	while (nsp->ns_instances != NULL) {
570 		if (ioctl(fd, SIOCGENITER, &obj) == -1)
571 			break;
572 		if ((filter != NULL) && (nat_matcharray(&nat, filter) == 0))
573 			continue;
574 		if (nat_fields != NULL) {
575 			for (i = 0; nat_fields[i].w_value != 0; i++) {
576 				printnatfield(&nat, nat_fields[i].w_value);
577 				if (nat_fields[i + 1].w_value != 0)
578 					printf("\t");
579 			}
580 			printf("\n");
581 		} else {
582 			printactivenat(&nat, opts, nsp->ns_ticks);
583 			if (nat.nat_aps) {
584 				int proto;
585 
586 				if (nat.nat_dir & NAT_OUTBOUND)
587 					proto = nat.nat_pr[1];
588 				else
589 					proto = nat.nat_pr[0];
590 				printaps(nat.nat_aps, opts, proto);
591 			}
592 		}
593 		nsp->ns_instances = nat.nat_next;
594 	}
595 
596 	if (opts & OPT_VERBOSE)
597 		showhostmap_live(fd, nsp);
598 
599 	i = IPFGENITER_NAT;
600 	(void) ioctl(fd,SIOCIPFDELTOK, &i);
601 }
602 
603 
604 /*
605  * Display the active host mapping table.
606  */
607 void
608 showhostmap_dead(natstat_t *nsp)
609 {
610 	hostmap_t hm, *hmp, **maptable;
611 	u_int hv;
612 
613 	printf("\nList of active host mappings:\n");
614 
615 	maptable = (hostmap_t **)malloc(sizeof(hostmap_t *) *
616 					nsp->ns_hostmap_sz);
617 	if (kmemcpy((char *)maptable, (u_long)nsp->ns_maptable,
618 		    sizeof(hostmap_t *) * nsp->ns_hostmap_sz)) {
619 		perror("kmemcpy (maptable)");
620 		return;
621 	}
622 
623 	for (hv = 0; hv < nsp->ns_hostmap_sz; hv++) {
624 		hmp = maptable[hv];
625 
626 		while (hmp) {
627 			if (kmemcpy((char *)&hm, (u_long)hmp, sizeof(hm))) {
628 				perror("kmemcpy (hostmap)");
629 				return;
630 			}
631 
632 			printhostmap(&hm, hv);
633 			hmp = hm.hm_next;
634 		}
635 	}
636 	free(maptable);
637 }
638 
639 
640 /*
641  * Display the active host mapping table.
642  */
643 void
644 showhostmap_live(int fd, natstat_t *nsp)
645 {
646 	ipfgeniter_t iter;
647 	hostmap_t hm;
648 	ipfobj_t obj;
649 	int i;
650 
651 	bzero((char *)&obj, sizeof(obj));
652 	obj.ipfo_rev = IPFILTER_VERSION;
653 	obj.ipfo_type = IPFOBJ_GENITER;
654 	obj.ipfo_size = sizeof(iter);
655 	obj.ipfo_ptr = &iter;
656 
657 	iter.igi_type = IPFGENITER_HOSTMAP;
658 	iter.igi_nitems = 1;
659 	iter.igi_data = &hm;
660 
661 	printf("\nList of active host mappings:\n");
662 
663 	while (nsp->ns_maplist != NULL) {
664 		if (ioctl(fd, SIOCGENITER, &obj) == -1)
665 			break;
666 		printhostmap(&hm, hm.hm_hv);
667 		nsp->ns_maplist = hm.hm_next;
668 	}
669 
670 	i = IPFGENITER_HOSTMAP;
671 	(void) ioctl(fd,SIOCIPFDELTOK, &i);
672 }
673 
674 
675 int
676 nat_matcharray(nat_t *nat, int *array)
677 {
678 	int i, n, *x, rv, p;
679 	ipfexp_t *e;
680 
681 	rv = 0;
682 	n = array[0];
683 	x = array + 1;
684 
685 	for (; n > 0; x += 3 + x[3], rv = 0) {
686 		e = (ipfexp_t *)x;
687 		if (e->ipfe_cmd == IPF_EXP_END)
688 			break;
689 		n -= e->ipfe_size;
690 
691 		p = e->ipfe_cmd >> 16;
692 		if ((p != 0) && (p != nat->nat_pr[1]))
693 			break;
694 
695 		switch (e->ipfe_cmd)
696 		{
697 		case IPF_EXP_IP_PR :
698 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
699 				rv |= (nat->nat_pr[1] == e->ipfe_arg0[i]);
700 			}
701 			break;
702 
703 		case IPF_EXP_IP_SRCADDR :
704 			if (nat->nat_v[0] != 4)
705 				break;
706 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
707 				rv |= ((nat->nat_osrcaddr &
708 					e->ipfe_arg0[i * 2 + 1]) ==
709 				       e->ipfe_arg0[i * 2]) ||
710 				      ((nat->nat_nsrcaddr &
711 					e->ipfe_arg0[i * 2 + 1]) ==
712 				       e->ipfe_arg0[i * 2]);
713 			}
714 			break;
715 
716 		case IPF_EXP_IP_DSTADDR :
717 			if (nat->nat_v[0] != 4)
718 				break;
719 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
720 				rv |= ((nat->nat_odstaddr &
721 					e->ipfe_arg0[i * 2 + 1]) ==
722 				       e->ipfe_arg0[i * 2]) ||
723 				      ((nat->nat_ndstaddr &
724 					e->ipfe_arg0[i * 2 + 1]) ==
725 				       e->ipfe_arg0[i * 2]);
726 			}
727 			break;
728 
729 		case IPF_EXP_IP_ADDR :
730 			if (nat->nat_v[0] != 4)
731 				break;
732 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
733 				rv |= ((nat->nat_osrcaddr &
734 					e->ipfe_arg0[i * 2 + 1]) ==
735 				       e->ipfe_arg0[i * 2]) ||
736 				      ((nat->nat_nsrcaddr &
737 					e->ipfe_arg0[i * 2 + 1]) ==
738 				       e->ipfe_arg0[i * 2]) ||
739 				     ((nat->nat_odstaddr &
740 					e->ipfe_arg0[i * 2 + 1]) ==
741 				       e->ipfe_arg0[i * 2]) ||
742 				     ((nat->nat_ndstaddr &
743 					e->ipfe_arg0[i * 2 + 1]) ==
744 				       e->ipfe_arg0[i * 2]);
745 			}
746 			break;
747 
748 #ifdef USE_INET6
749 		case IPF_EXP_IP6_SRCADDR :
750 			if (nat->nat_v[0] != 6)
751 				break;
752 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
753 				rv |= IP6_MASKEQ(&nat->nat_osrc6,
754 						 &e->ipfe_arg0[i * 8 + 4],
755 						 &e->ipfe_arg0[i * 8]) ||
756 				      IP6_MASKEQ(&nat->nat_nsrc6,
757 						 &e->ipfe_arg0[i * 8 + 4],
758 						 &e->ipfe_arg0[i * 8]);
759 			}
760 			break;
761 
762 		case IPF_EXP_IP6_DSTADDR :
763 			if (nat->nat_v[0] != 6)
764 				break;
765 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
766 				rv |= IP6_MASKEQ(&nat->nat_odst6,
767 						 &e->ipfe_arg0[i * 8 + 4],
768 						 &e->ipfe_arg0[i * 8]) ||
769 				      IP6_MASKEQ(&nat->nat_ndst6,
770 						 &e->ipfe_arg0[i * 8 + 4],
771 						 &e->ipfe_arg0[i * 8]);
772 			}
773 			break;
774 
775 		case IPF_EXP_IP6_ADDR :
776 			if (nat->nat_v[0] != 6)
777 				break;
778 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
779 				rv |= IP6_MASKEQ(&nat->nat_osrc6,
780 						 &e->ipfe_arg0[i * 8 + 4],
781 						 &e->ipfe_arg0[i * 8]) ||
782 				      IP6_MASKEQ(&nat->nat_nsrc6,
783 						 &e->ipfe_arg0[i * 8 + 4],
784 						 &e->ipfe_arg0[i * 8]) ||
785 				      IP6_MASKEQ(&nat->nat_odst6,
786 						 &e->ipfe_arg0[i * 8 + 4],
787 						 &e->ipfe_arg0[i * 8]) ||
788 				      IP6_MASKEQ(&nat->nat_ndst6,
789 						 &e->ipfe_arg0[i * 8 + 4],
790 						 &e->ipfe_arg0[i * 8]);
791 			}
792 			break;
793 #endif
794 
795 		case IPF_EXP_UDP_PORT :
796 		case IPF_EXP_TCP_PORT :
797 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
798 				rv |= (nat->nat_osport == e->ipfe_arg0[i]) ||
799 				      (nat->nat_nsport == e->ipfe_arg0[i]) ||
800 				      (nat->nat_odport == e->ipfe_arg0[i]) ||
801 				      (nat->nat_ndport == e->ipfe_arg0[i]);
802 			}
803 			break;
804 
805 		case IPF_EXP_UDP_SPORT :
806 		case IPF_EXP_TCP_SPORT :
807 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
808 				rv |= (nat->nat_osport == e->ipfe_arg0[i]) ||
809 				      (nat->nat_nsport == e->ipfe_arg0[i]);
810 			}
811 			break;
812 
813 		case IPF_EXP_UDP_DPORT :
814 		case IPF_EXP_TCP_DPORT :
815 			for (i = 0; !rv && i < e->ipfe_narg; i++) {
816 				rv |= (nat->nat_odport == e->ipfe_arg0[i]) ||
817 				      (nat->nat_ndport == e->ipfe_arg0[i]);
818 			}
819 			break;
820 		}
821 		rv ^= e->ipfe_not;
822 
823 		if (rv == 0)
824 			break;
825 	}
826 
827 	return (rv);
828 }
829