xref: /freebsd/sbin/ipfw/main.c (revision 66df505066f51e6d8411b966765d828817f88971)
1 /*-
2  * Copyright (c) 2002-2003,2010 Luigi Rizzo
3  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
4  * Copyright (c) 1994 Ugen J.S.Antsilevich
5  *
6  * Idea and grammar partially left from:
7  * Copyright (c) 1993 Daniel Boulet
8  *
9  * Redistribution and use in source forms, with and without modification,
10  * are permitted provided that this entire comment appears intact.
11  *
12  * Redistribution in binary form may occur without any restrictions.
13  * Obviously, it would be nice if you gave credit where credit is due
14  * but requiring it would be too onerous.
15  *
16  * This software is provided ``AS IS'' without any warranties of any kind.
17  *
18  * Command line interface for IP firewall facility
19  *
20  * $FreeBSD$
21  */
22 
23 #include <sys/wait.h>
24 #include <ctype.h>
25 #include <err.h>
26 #include <errno.h>
27 #include <signal.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <sysexits.h>
32 #include <unistd.h>
33 
34 #include "ipfw2.h"
35 
36 static void
37 help(void)
38 {
39 	if (is_ipfw()) {
40 		fprintf(stderr,
41 "ipfw syntax summary (but please do read the ipfw(8) manpage):\n\n"
42 "\tipfw [-abcdefhnNqStTv] <command>\n\n"
43 "where <command> is one of the following:\n\n"
44 "add [num] [set N] [prob x] RULE-BODY\n"
45 "{pipe|queue} N config PIPE-BODY\n"
46 "[pipe|queue] {zero|delete|show} [N{,N}]\n"
47 "nat N config {ip IPADDR|if IFNAME|log|deny_in|same_ports|unreg_only|unreg_cgn|\n"
48 "		reset|reverse|proxy_only|redirect_addr linkspec|\n"
49 "		redirect_port linkspec|redirect_proto linkspec|\n"
50 "		port_range lower-upper}\n"
51 "set [disable N... enable N...] | move [rule] X to Y | swap X Y | show\n"
52 "set N {show|list|zero|resetlog|delete} [N{,N}] | flush\n"
53 "table N {add ip[/bits] [value] | delete ip[/bits] | flush | list}\n"
54 "table all {flush | list}\n"
55 "\n"
56 "RULE-BODY:	check-state [PARAMS] | ACTION [PARAMS] ADDR [OPTION_LIST]\n"
57 "ACTION:	check-state | allow | count | deny | unreach{,6} CODE |\n"
58 "               skipto N | {divert|tee} PORT | forward ADDR |\n"
59 "               pipe N | queue N | nat N | setfib FIB | reass\n"
60 "PARAMS: 	[log [logamount LOGLIMIT]] [altq QUEUE_NAME]\n"
61 "ADDR:		[ MAC dst src ether_type ] \n"
62 "		[ ip from IPADDR [ PORT ] to IPADDR [ PORTLIST ] ]\n"
63 "		[ ipv6|ip6 from IP6ADDR [ PORT ] to IP6ADDR [ PORTLIST ] ]\n"
64 "IPADDR:	[not] { any | me | ip/bits{x,y,z} | table(t[,v]) | IPLIST }\n"
65 "IP6ADDR:	[not] { any | me | me6 | ip6/bits | IP6LIST }\n"
66 "IP6LIST:	{ ip6 | ip6/bits }[,IP6LIST]\n"
67 "IPLIST:	{ ip | ip/bits | ip:mask }[,IPLIST]\n"
68 "OPTION_LIST:	OPTION [OPTION_LIST]\n"
69 "OPTION:	bridged | diverted | diverted-loopback | diverted-output |\n"
70 "	{dst-ip|src-ip} IPADDR | {dst-ip6|src-ip6|dst-ipv6|src-ipv6} IP6ADDR |\n"
71 "	{dst-port|src-port} LIST |\n"
72 "	estab | frag | {gid|uid} N | icmptypes LIST | in | out | ipid LIST |\n"
73 "	iplen LIST | ipoptions SPEC | ipprecedence | ipsec | iptos SPEC |\n"
74 "	ipttl LIST | ipversion VER | keep-state | layer2 | limit ... |\n"
75 "	icmp6types LIST | ext6hdr LIST | flow-id N[,N] | fib FIB |\n"
76 "	mac ... | mac-type LIST | proto LIST | {recv|xmit|via} {IF|IPADDR} |\n"
77 "	setup | {tcpack|tcpseq|tcpwin} NN | tcpflags SPEC | tcpoptions SPEC |\n"
78 "	tcpdatalen LIST | verrevpath | versrcreach | antispoof\n"
79 );
80 	} else {
81 		fprintf(stderr,
82 "dnctl syntax summary (but please do read the dnctl(8) manpage):\n\n"
83 "\tdnctl [-hnsv] <command>\n\n"
84 "where <command> is one of the following:\n\n"
85 "[pipe|queue|sched] N config PIPE-BODY\n"
86 "[pipe|queue|sched] {delete|list|show} [N{,N}]\n"
87 "\n"
88 );
89 	}
90 
91 	exit(0);
92 }
93 
94 /*
95  * Called with the arguments, including program name because getopt
96  * wants it to be present.
97  * Returns 0 if successful, 1 if empty command, errx() in case of errors.
98  * First thing we do is process parameters creating an argv[] array
99  * which includes the program name and a NULL entry at the end.
100  * If we are called with a single string, we split it on whitespace.
101  * Also, arguments with a trailing ',' are joined to the next one.
102  * The pointers (av[]) and data are in a single chunk of memory.
103  * av[0] points to the original program name, all other entries
104  * point into the allocated chunk.
105  */
106 static int
107 ipfw_main(int oldac, char **oldav)
108 {
109 	int ch, ac;
110 	const char *errstr;
111 	char **av, **save_av;
112 	int do_acct = 0;		/* Show packet/byte count */
113 	int try_next = 0;		/* set if pipe cmd not found */
114 	int av_size;			/* compute the av size */
115 	char *av_p;			/* used to build the av list */
116 
117 #define WHITESP		" \t\f\v\n\r"
118 	if (oldac < 2)
119 		return 1;	/* need at least one argument */
120 
121 	if (oldac == 2) {
122 		/*
123 		 * If we are called with one argument, try to split it into
124 		 * words for subsequent parsing. Spaces after a ',' are
125 		 * removed by copying the string in-place.
126 		 */
127 		char *arg = oldav[1];	/* The string is the first arg. */
128 		int l = strlen(arg);
129 		int copy = 0;		/* 1 if we need to copy, 0 otherwise */
130 		int i, j;
131 
132 		for (i = j = 0; i < l; i++) {
133 			if (arg[i] == '#')	/* comment marker */
134 				break;
135 			if (copy) {
136 				arg[j++] = arg[i];
137 				copy = !strchr("," WHITESP, arg[i]);
138 			} else {
139 				copy = !strchr(WHITESP, arg[i]);
140 				if (copy)
141 					arg[j++] = arg[i];
142 			}
143 		}
144 		if (!copy && j > 0)	/* last char was a 'blank', remove it */
145 			j--;
146 		l = j;			/* the new argument length */
147 		arg[j++] = '\0';
148 		if (l == 0)		/* empty string! */
149 			return 1;
150 
151 		/*
152 		 * First, count number of arguments. Because of the previous
153 		 * processing, this is just the number of blanks plus 1.
154 		 */
155 		for (i = 0, ac = 1; i < l; i++)
156 			if (strchr(WHITESP, arg[i]) != NULL)
157 				ac++;
158 
159 		/*
160 		 * Allocate the argument list structure as a single block
161 		 * of memory, containing pointers and the argument
162 		 * strings. We include one entry for the program name
163 		 * because getopt expects it, and a NULL at the end
164 		 * to simplify further parsing.
165 		 */
166 		ac++;		/* add 1 for the program name */
167 		av_size = (ac+1) * sizeof(char *) + l + 1;
168 		av = safe_calloc(av_size, 1);
169 
170 		/*
171 		 * Init the argument pointer to the end of the array
172 		 * and copy arguments from arg[] to av[]. For each one,
173 		 * j is the initial character, i is the one past the end.
174 		 */
175 		av_p = (char *)&av[ac+1];
176 		for (ac = 1, i = j = 0; i < l; i++) {
177 			if (strchr(WHITESP, arg[i]) != NULL || i == l-1) {
178 				if (i == l-1)
179 					i++;
180 				bcopy(arg+j, av_p, i-j);
181 				av[ac] = av_p;
182 				av_p += i-j;	/* the length of the string */
183 				*av_p++ = '\0';
184 				ac++;
185 				j = i + 1;
186 			}
187 		}
188 	} else {
189 		/*
190 		 * If an argument ends with ',' join with the next one.
191 		 */
192 		int first, i, l=0;
193 
194 		/*
195 		 * Allocate the argument list structure as a single block
196 		 * of memory, containing both pointers and the argument
197 		 * strings. We include some space for the program name
198 		 * because getopt expects it.
199 		 * We add an extra pointer to the end of the array,
200 		 * to make simpler further parsing.
201 		 */
202 		for (i=0; i<oldac; i++)
203 			l += strlen(oldav[i]);
204 
205 		av_size = (oldac+1) * sizeof(char *) + l + oldac;
206 		av = safe_calloc(av_size, 1);
207 
208 		/*
209 		 * Init the argument pointer to the end of the array
210 		 * and copy arguments from arg[] to av[]
211 		 */
212 		av_p = (char *)&av[oldac+1];
213 		for (first = i = ac = 1, l = 0; i < oldac; i++) {
214 			char *arg = oldav[i];
215 			int k = strlen(arg);
216 
217 			l += k;
218 			if (arg[k-1] != ',' || i == oldac-1) {
219 				/* Time to copy. */
220 				av[ac] = av_p;
221 				for (l=0; first <= i; first++) {
222 					strcat(av_p, oldav[first]);
223 					av_p += strlen(oldav[first]);
224 				}
225 				*av_p++ = '\0';
226 				ac++;
227 				l = 0;
228 				first = i+1;
229 			}
230 		}
231 	}
232 
233 	/*
234 	 * set the progname pointer to the original string
235 	 * and terminate the array with null
236 	 */
237 	av[0] = oldav[0];
238 	av[ac] = NULL;
239 
240 	/* Set the force flag for non-interactive processes */
241 	if (!g_co.do_force)
242 		g_co.do_force = !isatty(STDIN_FILENO);
243 
244 #ifdef EMULATE_SYSCTL /* sysctl emulation */
245 	if (is_ipfw() && ac >= 2 &&
246 	    !strcmp(av[1], "sysctl")) {
247 		char *s;
248 		int i;
249 
250 		if (ac != 3) {
251 			printf(	"sysctl emulation usage:\n"
252 				"	ipfw sysctl name[=value]\n"
253 				"	ipfw sysctl -a\n");
254 			return 0;
255 		}
256 		s = strchr(av[2], '=');
257 		if (s == NULL) {
258 			s = !strcmp(av[2], "-a") ? NULL : av[2];
259 			sysctlbyname(s, NULL, NULL, NULL, 0);
260 		} else {	/* ipfw sysctl x.y.z=value */
261 			/* assume an INT value, will extend later */
262 			if (s[1] == '\0') {
263 				printf("ipfw sysctl: missing value\n\n");
264 				return 0;
265 			}
266 			*s = '\0';
267 			i = strtol(s+1, NULL, 0);
268 			sysctlbyname(av[2], NULL, NULL, &i, sizeof(int));
269 		}
270 		return 0;
271 	}
272 #endif
273 
274 	/* Save arguments for final freeing of memory. */
275 	save_av = av;
276 
277 	optind = optreset = 1;	/* restart getopt() */
278 	if (is_ipfw()) {
279 		while ((ch = getopt(ac, av, "abcdDefhinNp:qs:STtv")) != -1)
280 			switch (ch) {
281 			case 'a':
282 				do_acct = 1;
283 				break;
284 
285 			case 'b':
286 				g_co.comment_only = 1;
287 				g_co.do_compact = 1;
288 				break;
289 
290 			case 'c':
291 				g_co.do_compact = 1;
292 				break;
293 
294 			case 'd':
295 				g_co.do_dynamic = 1;
296 				break;
297 
298 			case 'D':
299 				g_co.do_dynamic = 2;
300 				break;
301 
302 			case 'e':
303 				/* nop for compatibility */
304 				break;
305 
306 			case 'f':
307 				g_co.do_force = 1;
308 				break;
309 
310 			case 'h': /* help */
311 				free(save_av);
312 				help();
313 				break;	/* NOTREACHED */
314 
315 			case 'i':
316 				g_co.do_value_as_ip = 1;
317 				break;
318 
319 			case 'n':
320 				g_co.test_only = 1;
321 				break;
322 
323 			case 'N':
324 				g_co.do_resolv = 1;
325 				break;
326 
327 			case 'p':
328 				errx(EX_USAGE, "An absolute pathname must be used "
329 				    "with -p option.");
330 				/* NOTREACHED */
331 
332 			case 'q':
333 				g_co.do_quiet = 1;
334 				break;
335 
336 			case 's': /* sort */
337 				g_co.do_sort = atoi(optarg);
338 				break;
339 
340 			case 'S':
341 				g_co.show_sets = 1;
342 				break;
343 
344 			case 't':
345 				g_co.do_time = TIMESTAMP_STRING;
346 				break;
347 
348 			case 'T':
349 				g_co.do_time = TIMESTAMP_NUMERIC;
350 				break;
351 
352 			case 'v': /* verbose */
353 				g_co.verbose = 1;
354 				break;
355 
356 			default:
357 				free(save_av);
358 				return 1;
359 			}
360 	} else {
361 		while ((ch = getopt(ac, av, "hns:v")) != -1)
362 			switch (ch) {
363 
364 			case 'h': /* help */
365 				free(save_av);
366 				help();
367 				break;	/* NOTREACHED */
368 
369 			case 'n':
370 				g_co.test_only = 1;
371 				break;
372 
373 			case 's': /* sort */
374 				g_co.do_sort = atoi(optarg);
375 				break;
376 
377 			case 'v': /* verbose */
378 				g_co.verbose = 1;
379 				break;
380 
381 			default:
382 				free(save_av);
383 				return 1;
384 			}
385 
386 	}
387 
388 	ac -= optind;
389 	av += optind;
390 	NEED1("bad arguments, for usage summary ``ipfw''");
391 
392 	/*
393 	 * An undocumented behaviour of ipfw1 was to allow rule numbers first,
394 	 * e.g. "100 add allow ..." instead of "add 100 allow ...".
395 	 * In case, swap first and second argument to get the normal form.
396 	 */
397 	if (ac > 1 && isdigit(*av[0])) {
398 		char *p = av[0];
399 
400 		av[0] = av[1];
401 		av[1] = p;
402 	}
403 
404 	/*
405 	 * Optional: pipe, queue or nat.
406 	 */
407 	g_co.do_nat = 0;
408 	g_co.do_pipe = 0;
409 	g_co.use_set = 0;
410 	if (is_ipfw() && !strncmp(*av, "nat", strlen(*av)))
411 		g_co.do_nat = 1;
412 	else if (!strncmp(*av, "pipe", strlen(*av)))
413 		g_co.do_pipe = 1;
414 	else if (_substrcmp(*av, "queue") == 0)
415 		g_co.do_pipe = 2;
416 	else if (_substrcmp(*av, "flowset") == 0)
417 		g_co.do_pipe = 2;
418 	else if (_substrcmp(*av, "sched") == 0)
419 		g_co.do_pipe = 3;
420 	else if (is_ipfw() && !strncmp(*av, "set", strlen(*av))) {
421 		if (ac > 1 && isdigit(av[1][0])) {
422 			g_co.use_set = strtonum(av[1], 0, resvd_set_number,
423 					&errstr);
424 			if (errstr)
425 				errx(EX_DATAERR,
426 				    "invalid set number %s\n", av[1]);
427 			ac -= 2; av += 2; g_co.use_set++;
428 		}
429 	}
430 
431 	if (g_co.do_pipe || g_co.do_nat) {
432 		ac--;
433 		av++;
434 	}
435 	NEED1("missing command");
436 
437 	/*
438 	 * For pipes, queues and nats we normally say 'nat|pipe NN config'
439 	 * but the code is easier to parse as 'nat|pipe config NN'
440 	 * so we swap the two arguments.
441 	 */
442 	if ((g_co.do_pipe || g_co.do_nat) && ac > 1 && isdigit(*av[0])) {
443 		char *p = av[0];
444 
445 		av[0] = av[1];
446 		av[1] = p;
447 	}
448 
449 	if (! is_ipfw() && g_co.do_pipe == 0) {
450 		help();
451 	}
452 
453 	if (g_co.use_set == 0) {
454 		if (is_ipfw() && _substrcmp(*av, "add") == 0)
455 			ipfw_add(av);
456 		else if (g_co.do_nat && _substrcmp(*av, "show") == 0)
457  			ipfw_show_nat(ac, av);
458 		else if (g_co.do_pipe && _substrcmp(*av, "config") == 0)
459 			ipfw_config_pipe(ac, av);
460 		else if (g_co.do_nat && _substrcmp(*av, "config") == 0)
461  			ipfw_config_nat(ac, av);
462 		else if (is_ipfw() && _substrcmp(*av, "set") == 0)
463 			ipfw_sets_handler(av);
464 		else if (is_ipfw() && _substrcmp(*av, "table") == 0)
465 			ipfw_table_handler(ac, av);
466 		else if (is_ipfw() && _substrcmp(*av, "enable") == 0)
467 			ipfw_sysctl_handler(av, 1);
468 		else if (is_ipfw() && _substrcmp(*av, "disable") == 0)
469 			ipfw_sysctl_handler(av, 0);
470 		else
471 			try_next = 1;
472 	}
473 
474 	if (g_co.use_set || try_next) {
475 		if (_substrcmp(*av, "delete") == 0)
476 			ipfw_delete(av);
477 		else if (is_ipfw() && !strncmp(*av, "nat64clat", strlen(*av)))
478 			ipfw_nat64clat_handler(ac, av);
479 		else if (is_ipfw() && !strncmp(*av, "nat64stl", strlen(*av)))
480 			ipfw_nat64stl_handler(ac, av);
481 		else if (is_ipfw() && !strncmp(*av, "nat64lsn", strlen(*av)))
482 			ipfw_nat64lsn_handler(ac, av);
483 		else if (is_ipfw() && !strncmp(*av, "nptv6", strlen(*av)))
484 			ipfw_nptv6_handler(ac, av);
485 		else if (_substrcmp(*av, "flush") == 0)
486 			ipfw_flush(g_co.do_force);
487 		else if (is_ipfw() && _substrcmp(*av, "zero") == 0)
488 			ipfw_zero(ac, av, 0 /* IP_FW_ZERO */);
489 		else if (is_ipfw() && _substrcmp(*av, "resetlog") == 0)
490 			ipfw_zero(ac, av, 1 /* IP_FW_RESETLOG */);
491 		else if (_substrcmp(*av, "print") == 0 ||
492 			 _substrcmp(*av, "list") == 0)
493 			ipfw_list(ac, av, do_acct);
494 		else if (_substrcmp(*av, "show") == 0)
495 			ipfw_list(ac, av, 1 /* show counters */);
496 		else if (is_ipfw() && _substrcmp(*av, "table") == 0)
497 			ipfw_table_handler(ac, av);
498 		else if (is_ipfw() && _substrcmp(*av, "internal") == 0)
499 			ipfw_internal_handler(ac, av);
500 		else
501 			errx(EX_USAGE, "bad command `%s'", *av);
502 	}
503 
504 	/* Free memory allocated in the argument parsing. */
505 	free(save_av);
506 	return 0;
507 }
508 
509 
510 static void
511 ipfw_readfile(int ac, char *av[])
512 {
513 #define MAX_ARGS	32
514 	char buf[4096];
515 	char *progname = av[0];		/* original program name */
516 	const char *cmd = NULL;		/* preprocessor name, if any */
517 	const char *filename = av[ac-1]; /* file to read */
518 	int	c, lineno=0;
519 	FILE	*f = NULL;
520 	pid_t	preproc = 0;
521 
522 	while ((c = getopt(ac, av, "cfNnp:qS")) != -1) {
523 		switch(c) {
524 		case 'c':
525 			g_co.do_compact = 1;
526 			break;
527 
528 		case 'f':
529 			g_co.do_force = 1;
530 			break;
531 
532 		case 'N':
533 			g_co.do_resolv = 1;
534 			break;
535 
536 		case 'n':
537 			g_co.test_only = 1;
538 			break;
539 
540 		case 'p':
541 			/*
542 			 * ipfw -p cmd [args] filename
543 			 *
544 			 * We are done with getopt(). All arguments
545 			 * except the filename go to the preprocessor,
546 			 * so we need to do the following:
547 			 * - check that a filename is actually present;
548 			 * - advance av by optind-1 to skip arguments
549 			 *   already processed;
550 			 * - decrease ac by optind, to remove the args
551 			 *   already processed and the final filename;
552 			 * - set the last entry in av[] to NULL so
553 			 *   popen() can detect the end of the array;
554 			 * - set optind=ac to let getopt() terminate.
555 			 */
556 			if (optind == ac)
557 				errx(EX_USAGE, "no filename argument");
558 			cmd = optarg;
559 			av[ac-1] = NULL;
560 			av += optind - 1;
561 			ac -= optind;
562 			optind = ac;
563 			break;
564 
565 		case 'q':
566 			g_co.do_quiet = 1;
567 			break;
568 
569 		case 'S':
570 			g_co.show_sets = 1;
571 			break;
572 
573 		default:
574 			errx(EX_USAGE, "bad arguments, for usage"
575 			     " summary ``ipfw''");
576 		}
577 
578 	}
579 
580 	if (cmd == NULL && ac != optind + 1)
581 		errx(EX_USAGE, "extraneous filename arguments %s", av[ac-1]);
582 
583 	if ((f = fopen(filename, "r")) == NULL)
584 		err(EX_UNAVAILABLE, "fopen: %s", filename);
585 
586 	if (cmd != NULL) {			/* pipe through preprocessor */
587 		int pipedes[2];
588 
589 		if (pipe(pipedes) == -1)
590 			err(EX_OSERR, "cannot create pipe");
591 
592 		preproc = fork();
593 		if (preproc == -1)
594 			err(EX_OSERR, "cannot fork");
595 
596 		if (preproc == 0) {
597 			/*
598 			 * Child, will run the preprocessor with the
599 			 * file on stdin and the pipe on stdout.
600 			 */
601 			if (dup2(fileno(f), 0) == -1
602 			    || dup2(pipedes[1], 1) == -1)
603 				err(EX_OSERR, "dup2()");
604 			fclose(f);
605 			close(pipedes[1]);
606 			close(pipedes[0]);
607 			execvp(cmd, av);
608 			err(EX_OSERR, "execvp(%s) failed", cmd);
609 		} else { /* parent, will reopen f as the pipe */
610 			fclose(f);
611 			close(pipedes[1]);
612 			if ((f = fdopen(pipedes[0], "r")) == NULL) {
613 				int savederrno = errno;
614 
615 				(void)kill(preproc, SIGTERM);
616 				errno = savederrno;
617 				err(EX_OSERR, "fdopen()");
618 			}
619 		}
620 	}
621 
622 	while (fgets(buf, sizeof(buf), f)) {		/* read commands */
623 		char linename[20];
624 		char *args[2];
625 
626 		lineno++;
627 		snprintf(linename, sizeof(linename), "Line %d", lineno);
628 		setprogname(linename); /* XXX */
629 		args[0] = progname;
630 		args[1] = buf;
631 		ipfw_main(2, args);
632 	}
633 	fclose(f);
634 	if (cmd != NULL) {
635 		int status;
636 
637 		if (waitpid(preproc, &status, 0) == -1)
638 			errx(EX_OSERR, "waitpid()");
639 		if (WIFEXITED(status) && WEXITSTATUS(status) != EX_OK)
640 			errx(EX_UNAVAILABLE,
641 			    "preprocessor exited with status %d",
642 			    WEXITSTATUS(status));
643 		else if (WIFSIGNALED(status))
644 			errx(EX_UNAVAILABLE,
645 			    "preprocessor exited with signal %d",
646 			    WTERMSIG(status));
647 	}
648 }
649 
650 int
651 main(int ac, char *av[])
652 {
653 #if defined(_WIN32) && defined(TCC)
654 	{
655 		WSADATA wsaData;
656 		int ret=0;
657 		unsigned short wVersionRequested = MAKEWORD(2, 2);
658 		ret = WSAStartup(wVersionRequested, &wsaData);
659 		if (ret != 0) {
660 			/* Tell the user that we could not find a usable */
661 			/* Winsock DLL.				  */
662 			printf("WSAStartup failed with error: %d\n", ret);
663 			return 1;
664 		}
665 	}
666 #endif
667 
668 	if (strcmp(av[0], "dnctl") == 0)
669 		g_co.prog = cmdline_prog_dnctl;
670 	else
671 		g_co.prog = cmdline_prog_ipfw;
672 
673 	/*
674 	 * If the last argument is an absolute pathname, interpret it
675 	 * as a file to be preprocessed.
676 	 */
677 
678 	if (ac > 1 && av[ac - 1][0] == '/') {
679 		if (! is_ipfw())
680 			errx(EX_USAGE, "usage: dnctl [options]\n"
681 			    "do \"dnctl -h\" for details");
682 
683 		if (access(av[ac - 1], R_OK) == 0)
684 			ipfw_readfile(ac, av);
685 		else
686 			err(EX_USAGE, "pathname: %s", av[ac - 1]);
687 	} else {
688 		if (ipfw_main(ac, av)) {
689 			errx(EX_USAGE,
690 			    "usage: %s [options]\n"
691 			    "do \"%s -h\" or \"man %s\" for details", av[0],
692 			    av[0], av[0]);
693 		}
694 	}
695 	return EX_OK;
696 }
697