xref: /freebsd-13-stable/sbin/ipfw/main.c (revision 17da660ad5b3b9cd90e164dd4dbb9beaa7203054)
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 
21 #include <sys/wait.h>
22 #include <ctype.h>
23 #include <err.h>
24 #include <errno.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sysexits.h>
30 #include <unistd.h>
31 
32 #include "ipfw2.h"
33 
34 static void
help(void)35 help(void)
36 {
37 	if (is_ipfw()) {
38 		fprintf(stderr,
39 "ipfw syntax summary (but please do read the ipfw(8) manpage):\n\n"
40 "\tipfw [-abcdefhnNqStTv] <command>\n\n"
41 "where <command> is one of the following:\n\n"
42 "add [num] [set N] [prob x] RULE-BODY\n"
43 "{pipe|queue} N config PIPE-BODY\n"
44 "[pipe|queue] {zero|delete|show} [N{,N}]\n"
45 "nat N config {ip IPADDR|if IFNAME|log|deny_in|same_ports|unreg_only|unreg_cgn|\n"
46 "		reset|reverse|proxy_only|redirect_addr linkspec|\n"
47 "		redirect_port linkspec|redirect_proto linkspec|\n"
48 "		port_range lower-upper}\n"
49 "set [disable N... enable N...] | move [rule] X to Y | swap X Y | show\n"
50 "set N {show|list|zero|resetlog|delete} [N{,N}] | flush\n"
51 "table N {add ip[/bits] [value] | delete ip[/bits] | flush | list}\n"
52 "table all {flush | list}\n"
53 "\n"
54 "RULE-BODY:	check-state [PARAMS] | ACTION [PARAMS] ADDR [OPTION_LIST]\n"
55 "ACTION:	check-state | allow | count | deny | unreach{,6} CODE |\n"
56 "               skipto N | {divert|tee} PORT | forward ADDR |\n"
57 "               pipe N | queue N | nat N | setfib FIB | reass\n"
58 "PARAMS: 	[log [logamount LOGLIMIT]] [altq QUEUE_NAME]\n"
59 "ADDR:		[ MAC dst src ether_type ] \n"
60 "		[ ip from IPADDR [ PORT ] to IPADDR [ PORTLIST ] ]\n"
61 "		[ ipv6|ip6 from IP6ADDR [ PORT ] to IP6ADDR [ PORTLIST ] ]\n"
62 "IPADDR:	[not] { any | me | ip/bits{x,y,z} | table(t[,v]) | IPLIST }\n"
63 "IP6ADDR:	[not] { any | me | me6 | ip6/bits | IP6LIST }\n"
64 "IP6LIST:	{ ip6 | ip6/bits }[,IP6LIST]\n"
65 "IPLIST:	{ ip | ip/bits | ip:mask }[,IPLIST]\n"
66 "OPTION_LIST:	OPTION [OPTION_LIST]\n"
67 "OPTION:	bridged | diverted | diverted-loopback | diverted-output |\n"
68 "	{dst-ip|src-ip} IPADDR | {dst-ip6|src-ip6|dst-ipv6|src-ipv6} IP6ADDR |\n"
69 "	{dst-port|src-port} LIST |\n"
70 "	estab | frag | {gid|uid} N | icmptypes LIST | in | out | ipid LIST |\n"
71 "	iplen LIST | ipoptions SPEC | ipprecedence | ipsec | iptos SPEC |\n"
72 "	ipttl LIST | ipversion VER | keep-state | layer2 | limit ... |\n"
73 "	icmp6types LIST | ext6hdr LIST | flow-id N[,N] | fib FIB |\n"
74 "	mac ... | mac-type LIST | proto LIST | {recv|xmit|via} {IF|IPADDR} |\n"
75 "	setup | {tcpack|tcpseq|tcpwin} NN | tcpflags SPEC | tcpoptions SPEC |\n"
76 "	tcpdatalen LIST | verrevpath | versrcreach | antispoof\n"
77 );
78 	} else {
79 		fprintf(stderr,
80 "dnctl syntax summary (but please do read the dnctl(8) manpage):\n\n"
81 "\tdnctl [-hnsv] <command>\n\n"
82 "where <command> is one of the following:\n\n"
83 "[pipe|queue|sched] N config PIPE-BODY\n"
84 "[pipe|queue|sched] {delete|list|show} [N{,N}]\n"
85 "\n"
86 );
87 	}
88 
89 	exit(0);
90 }
91 
92 /*
93  * Called with the arguments, including program name because getopt
94  * wants it to be present.
95  * Returns 0 if successful, 1 if empty command, errx() in case of errors.
96  * First thing we do is process parameters creating an argv[] array
97  * which includes the program name and a NULL entry at the end.
98  * If we are called with a single string, we split it on whitespace.
99  * Also, arguments with a trailing ',' are joined to the next one.
100  * The pointers (av[]) and data are in a single chunk of memory.
101  * av[0] points to the original program name, all other entries
102  * point into the allocated chunk.
103  */
104 static int
ipfw_main(int oldac,char ** oldav)105 ipfw_main(int oldac, char **oldav)
106 {
107 	int ch, ac;
108 	const char *errstr;
109 	char **av, **save_av;
110 	int do_acct = 0;		/* Show packet/byte count */
111 	int try_next = 0;		/* set if pipe cmd not found */
112 	int av_size;			/* compute the av size */
113 	char *av_p;			/* used to build the av list */
114 
115 #define WHITESP		" \t\f\v\n\r"
116 	if (oldac < 2)
117 		return 1;	/* need at least one argument */
118 
119 	if (oldac == 2) {
120 		/*
121 		 * If we are called with one argument, try to split it into
122 		 * words for subsequent parsing. Spaces after a ',' are
123 		 * removed by copying the string in-place.
124 		 */
125 		char *arg = oldav[1];	/* The string is the first arg. */
126 		int l = strlen(arg);
127 		int copy = 0;		/* 1 if we need to copy, 0 otherwise */
128 		int i, j;
129 
130 		for (i = j = 0; i < l; i++) {
131 			if (arg[i] == '#')	/* comment marker */
132 				break;
133 			if (copy) {
134 				arg[j++] = arg[i];
135 				copy = !strchr("," WHITESP, arg[i]);
136 			} else {
137 				copy = !strchr(WHITESP, arg[i]);
138 				if (copy)
139 					arg[j++] = arg[i];
140 			}
141 		}
142 		if (!copy && j > 0)	/* last char was a 'blank', remove it */
143 			j--;
144 		l = j;			/* the new argument length */
145 		arg[j++] = '\0';
146 		if (l == 0)		/* empty string! */
147 			return 1;
148 
149 		/*
150 		 * First, count number of arguments. Because of the previous
151 		 * processing, this is just the number of blanks plus 1.
152 		 */
153 		for (i = 0, ac = 1; i < l; i++)
154 			if (strchr(WHITESP, arg[i]) != NULL)
155 				ac++;
156 
157 		/*
158 		 * Allocate the argument list structure as a single block
159 		 * of memory, containing pointers and the argument
160 		 * strings. We include one entry for the program name
161 		 * because getopt expects it, and a NULL at the end
162 		 * to simplify further parsing.
163 		 */
164 		ac++;		/* add 1 for the program name */
165 		av_size = (ac+1) * sizeof(char *) + l + 1;
166 		av = safe_calloc(av_size, 1);
167 
168 		/*
169 		 * Init the argument pointer to the end of the array
170 		 * and copy arguments from arg[] to av[]. For each one,
171 		 * j is the initial character, i is the one past the end.
172 		 */
173 		av_p = (char *)&av[ac+1];
174 		for (ac = 1, i = j = 0; i < l; i++) {
175 			if (strchr(WHITESP, arg[i]) != NULL || i == l-1) {
176 				if (i == l-1)
177 					i++;
178 				bcopy(arg+j, av_p, i-j);
179 				av[ac] = av_p;
180 				av_p += i-j;	/* the length of the string */
181 				*av_p++ = '\0';
182 				ac++;
183 				j = i + 1;
184 			}
185 		}
186 	} else {
187 		/*
188 		 * If an argument ends with ',' join with the next one.
189 		 */
190 		int first, i, l=0;
191 
192 		/*
193 		 * Allocate the argument list structure as a single block
194 		 * of memory, containing both pointers and the argument
195 		 * strings. We include some space for the program name
196 		 * because getopt expects it.
197 		 * We add an extra pointer to the end of the array,
198 		 * to make simpler further parsing.
199 		 */
200 		for (i=0; i<oldac; i++)
201 			l += strlen(oldav[i]);
202 
203 		av_size = (oldac+1) * sizeof(char *) + l + oldac;
204 		av = safe_calloc(av_size, 1);
205 
206 		/*
207 		 * Init the argument pointer to the end of the array
208 		 * and copy arguments from arg[] to av[]
209 		 */
210 		av_p = (char *)&av[oldac+1];
211 		for (first = i = ac = 1, l = 0; i < oldac; i++) {
212 			char *arg = oldav[i];
213 			int k = strlen(arg);
214 
215 			l += k;
216 			if (arg[k-1] != ',' || i == oldac-1) {
217 				/* Time to copy. */
218 				av[ac] = av_p;
219 				for (l=0; first <= i; first++) {
220 					strcat(av_p, oldav[first]);
221 					av_p += strlen(oldav[first]);
222 				}
223 				*av_p++ = '\0';
224 				ac++;
225 				l = 0;
226 				first = i+1;
227 			}
228 		}
229 	}
230 
231 	/*
232 	 * set the progname pointer to the original string
233 	 * and terminate the array with null
234 	 */
235 	av[0] = oldav[0];
236 	av[ac] = NULL;
237 
238 	/* Set the force flag for non-interactive processes */
239 	if (!g_co.do_force)
240 		g_co.do_force = !isatty(STDIN_FILENO);
241 
242 #ifdef EMULATE_SYSCTL /* sysctl emulation */
243 	if (is_ipfw() && ac >= 2 &&
244 	    !strcmp(av[1], "sysctl")) {
245 		char *s;
246 		int i;
247 
248 		if (ac != 3) {
249 			printf(	"sysctl emulation usage:\n"
250 				"	ipfw sysctl name[=value]\n"
251 				"	ipfw sysctl -a\n");
252 			return 0;
253 		}
254 		s = strchr(av[2], '=');
255 		if (s == NULL) {
256 			s = !strcmp(av[2], "-a") ? NULL : av[2];
257 			sysctlbyname(s, NULL, NULL, NULL, 0);
258 		} else {	/* ipfw sysctl x.y.z=value */
259 			/* assume an INT value, will extend later */
260 			if (s[1] == '\0') {
261 				printf("ipfw sysctl: missing value\n\n");
262 				return 0;
263 			}
264 			*s = '\0';
265 			i = strtol(s+1, NULL, 0);
266 			sysctlbyname(av[2], NULL, NULL, &i, sizeof(int));
267 		}
268 		return 0;
269 	}
270 #endif
271 
272 	/* Save arguments for final freeing of memory. */
273 	save_av = av;
274 
275 	optind = optreset = 1;	/* restart getopt() */
276 	if (is_ipfw()) {
277 		while ((ch = getopt(ac, av, "abcdDefhinNp:qs:STtv")) != -1)
278 			switch (ch) {
279 			case 'a':
280 				do_acct = 1;
281 				break;
282 
283 			case 'b':
284 				g_co.comment_only = 1;
285 				g_co.do_compact = 1;
286 				break;
287 
288 			case 'c':
289 				g_co.do_compact = 1;
290 				break;
291 
292 			case 'd':
293 				g_co.do_dynamic = 1;
294 				break;
295 
296 			case 'D':
297 				g_co.do_dynamic = 2;
298 				break;
299 
300 			case 'e':
301 				/* nop for compatibility */
302 				break;
303 
304 			case 'f':
305 				g_co.do_force = 1;
306 				break;
307 
308 			case 'h': /* help */
309 				free(save_av);
310 				help();
311 				break;	/* NOTREACHED */
312 
313 			case 'i':
314 				g_co.do_value_as_ip = 1;
315 				break;
316 
317 			case 'n':
318 				g_co.test_only = 1;
319 				break;
320 
321 			case 'N':
322 				g_co.do_resolv = 1;
323 				break;
324 
325 			case 'p':
326 				errx(EX_USAGE, "An absolute pathname must be used "
327 				    "with -p option.");
328 				/* NOTREACHED */
329 
330 			case 'q':
331 				g_co.do_quiet = 1;
332 				break;
333 
334 			case 's': /* sort */
335 				g_co.do_sort = atoi(optarg);
336 				break;
337 
338 			case 'S':
339 				g_co.show_sets = 1;
340 				break;
341 
342 			case 't':
343 				g_co.do_time = TIMESTAMP_STRING;
344 				break;
345 
346 			case 'T':
347 				g_co.do_time = TIMESTAMP_NUMERIC;
348 				break;
349 
350 			case 'v': /* verbose */
351 				g_co.verbose = 1;
352 				break;
353 
354 			default:
355 				free(save_av);
356 				return 1;
357 			}
358 	} else {
359 		while ((ch = getopt(ac, av, "hns:v")) != -1)
360 			switch (ch) {
361 
362 			case 'h': /* help */
363 				free(save_av);
364 				help();
365 				break;	/* NOTREACHED */
366 
367 			case 'n':
368 				g_co.test_only = 1;
369 				break;
370 
371 			case 's': /* sort */
372 				g_co.do_sort = atoi(optarg);
373 				break;
374 
375 			case 'v': /* verbose */
376 				g_co.verbose = 1;
377 				break;
378 
379 			default:
380 				free(save_av);
381 				return 1;
382 			}
383 
384 	}
385 
386 	ac -= optind;
387 	av += optind;
388 	NEED1("bad arguments, for usage summary ``ipfw''");
389 
390 	/*
391 	 * An undocumented behaviour of ipfw1 was to allow rule numbers first,
392 	 * e.g. "100 add allow ..." instead of "add 100 allow ...".
393 	 * In case, swap first and second argument to get the normal form.
394 	 */
395 	if (ac > 1 && isdigit(*av[0])) {
396 		char *p = av[0];
397 
398 		av[0] = av[1];
399 		av[1] = p;
400 	}
401 
402 	/*
403 	 * Optional: pipe, queue or nat.
404 	 */
405 	g_co.do_nat = 0;
406 	g_co.do_pipe = 0;
407 	g_co.use_set = 0;
408 	if (is_ipfw() && !strncmp(*av, "nat", strlen(*av)))
409 		g_co.do_nat = 1;
410 	else if (!strncmp(*av, "pipe", strlen(*av)))
411 		g_co.do_pipe = 1;
412 	else if (_substrcmp(*av, "queue") == 0)
413 		g_co.do_pipe = 2;
414 	else if (_substrcmp(*av, "flowset") == 0)
415 		g_co.do_pipe = 2;
416 	else if (_substrcmp(*av, "sched") == 0)
417 		g_co.do_pipe = 3;
418 	else if (is_ipfw() && !strncmp(*av, "set", strlen(*av))) {
419 		if (ac > 1 && isdigit(av[1][0])) {
420 			g_co.use_set = strtonum(av[1], 0, resvd_set_number,
421 					&errstr);
422 			if (errstr)
423 				errx(EX_DATAERR,
424 				    "invalid set number %s\n", av[1]);
425 			ac -= 2; av += 2; g_co.use_set++;
426 		}
427 	}
428 
429 	if (g_co.do_pipe || g_co.do_nat) {
430 		ac--;
431 		av++;
432 	}
433 	NEED1("missing command");
434 
435 	/*
436 	 * For pipes, queues and nats we normally say 'nat|pipe NN config'
437 	 * but the code is easier to parse as 'nat|pipe config NN'
438 	 * so we swap the two arguments.
439 	 */
440 	if ((g_co.do_pipe || g_co.do_nat) && ac > 1 && isdigit(*av[0])) {
441 		char *p = av[0];
442 
443 		av[0] = av[1];
444 		av[1] = p;
445 	}
446 
447 	if (! is_ipfw() && g_co.do_pipe == 0) {
448 		help();
449 	}
450 
451 	if (g_co.use_set == 0) {
452 		if (is_ipfw() && _substrcmp(*av, "add") == 0)
453 			ipfw_add(av);
454 		else if (g_co.do_nat && _substrcmp(*av, "show") == 0)
455  			ipfw_show_nat(ac, av);
456 		else if (g_co.do_pipe && _substrcmp(*av, "config") == 0)
457 			ipfw_config_pipe(ac, av);
458 		else if (g_co.do_nat && _substrcmp(*av, "config") == 0)
459  			ipfw_config_nat(ac, av);
460 		else if (is_ipfw() && _substrcmp(*av, "set") == 0)
461 			ipfw_sets_handler(av);
462 		else if (is_ipfw() && _substrcmp(*av, "table") == 0)
463 			ipfw_table_handler(ac, av);
464 		else if (is_ipfw() && _substrcmp(*av, "enable") == 0)
465 			ipfw_sysctl_handler(av, 1);
466 		else if (is_ipfw() && _substrcmp(*av, "disable") == 0)
467 			ipfw_sysctl_handler(av, 0);
468 		else
469 			try_next = 1;
470 	}
471 
472 	if (g_co.use_set || try_next) {
473 		if (_substrcmp(*av, "delete") == 0)
474 			ipfw_delete(av);
475 		else if (is_ipfw() && !strncmp(*av, "nat64clat", strlen(*av)))
476 			ipfw_nat64clat_handler(ac, av);
477 		else if (is_ipfw() && !strncmp(*av, "nat64stl", strlen(*av)))
478 			ipfw_nat64stl_handler(ac, av);
479 		else if (is_ipfw() && !strncmp(*av, "nat64lsn", strlen(*av)))
480 			ipfw_nat64lsn_handler(ac, av);
481 		else if (is_ipfw() && !strncmp(*av, "nptv6", strlen(*av)))
482 			ipfw_nptv6_handler(ac, av);
483 		else if (_substrcmp(*av, "flush") == 0)
484 			ipfw_flush(g_co.do_force);
485 		else if (is_ipfw() && _substrcmp(*av, "zero") == 0)
486 			ipfw_zero(ac, av, 0 /* IP_FW_ZERO */);
487 		else if (is_ipfw() && _substrcmp(*av, "resetlog") == 0)
488 			ipfw_zero(ac, av, 1 /* IP_FW_RESETLOG */);
489 		else if (_substrcmp(*av, "print") == 0 ||
490 			 _substrcmp(*av, "list") == 0)
491 			ipfw_list(ac, av, do_acct);
492 		else if (_substrcmp(*av, "show") == 0)
493 			ipfw_list(ac, av, 1 /* show counters */);
494 		else if (is_ipfw() && _substrcmp(*av, "table") == 0)
495 			ipfw_table_handler(ac, av);
496 		else if (is_ipfw() && _substrcmp(*av, "internal") == 0)
497 			ipfw_internal_handler(ac, av);
498 		else
499 			errx(EX_USAGE, "bad command `%s'", *av);
500 	}
501 
502 	/* Free memory allocated in the argument parsing. */
503 	free(save_av);
504 	return 0;
505 }
506 
507 
508 static void
ipfw_readfile(int ac,char * av[])509 ipfw_readfile(int ac, char *av[])
510 {
511 #define MAX_ARGS	32
512 	char buf[4096];
513 	char *progname = av[0];		/* original program name */
514 	const char *cmd = NULL;		/* preprocessor name, if any */
515 	const char *filename = av[ac-1]; /* file to read */
516 	int	c, lineno=0;
517 	FILE	*f = NULL;
518 	pid_t	preproc = 0;
519 
520 	while ((c = getopt(ac, av, "cfNnp:qS")) != -1) {
521 		switch(c) {
522 		case 'c':
523 			g_co.do_compact = 1;
524 			break;
525 
526 		case 'f':
527 			g_co.do_force = 1;
528 			break;
529 
530 		case 'N':
531 			g_co.do_resolv = 1;
532 			break;
533 
534 		case 'n':
535 			g_co.test_only = 1;
536 			break;
537 
538 		case 'p':
539 			/*
540 			 * ipfw -p cmd [args] filename
541 			 *
542 			 * We are done with getopt(). All arguments
543 			 * except the filename go to the preprocessor,
544 			 * so we need to do the following:
545 			 * - check that a filename is actually present;
546 			 * - advance av by optind-1 to skip arguments
547 			 *   already processed;
548 			 * - decrease ac by optind, to remove the args
549 			 *   already processed and the final filename;
550 			 * - set the last entry in av[] to NULL so
551 			 *   popen() can detect the end of the array;
552 			 * - set optind=ac to let getopt() terminate.
553 			 */
554 			if (optind == ac)
555 				errx(EX_USAGE, "no filename argument");
556 			cmd = optarg;
557 			av[ac-1] = NULL;
558 			av += optind - 1;
559 			ac -= optind;
560 			optind = ac;
561 			break;
562 
563 		case 'q':
564 			g_co.do_quiet = 1;
565 			break;
566 
567 		case 'S':
568 			g_co.show_sets = 1;
569 			break;
570 
571 		default:
572 			errx(EX_USAGE, "bad arguments, for usage"
573 			     " summary ``ipfw''");
574 		}
575 
576 	}
577 
578 	if (cmd == NULL && ac != optind + 1)
579 		errx(EX_USAGE, "extraneous filename arguments %s", av[ac-1]);
580 
581 	if ((f = fopen(filename, "r")) == NULL)
582 		err(EX_UNAVAILABLE, "fopen: %s", filename);
583 
584 	if (cmd != NULL) {			/* pipe through preprocessor */
585 		int pipedes[2];
586 
587 		if (pipe(pipedes) == -1)
588 			err(EX_OSERR, "cannot create pipe");
589 
590 		preproc = fork();
591 		if (preproc == -1)
592 			err(EX_OSERR, "cannot fork");
593 
594 		if (preproc == 0) {
595 			/*
596 			 * Child, will run the preprocessor with the
597 			 * file on stdin and the pipe on stdout.
598 			 */
599 			if (dup2(fileno(f), 0) == -1
600 			    || dup2(pipedes[1], 1) == -1)
601 				err(EX_OSERR, "dup2()");
602 			fclose(f);
603 			close(pipedes[1]);
604 			close(pipedes[0]);
605 			execvp(cmd, av);
606 			err(EX_OSERR, "execvp(%s) failed", cmd);
607 		} else { /* parent, will reopen f as the pipe */
608 			fclose(f);
609 			close(pipedes[1]);
610 			if ((f = fdopen(pipedes[0], "r")) == NULL) {
611 				int savederrno = errno;
612 
613 				(void)kill(preproc, SIGTERM);
614 				errno = savederrno;
615 				err(EX_OSERR, "fdopen()");
616 			}
617 		}
618 	}
619 
620 	while (fgets(buf, sizeof(buf), f)) {		/* read commands */
621 		char linename[20];
622 		char *args[2];
623 
624 		lineno++;
625 		snprintf(linename, sizeof(linename), "Line %d", lineno);
626 		setprogname(linename); /* XXX */
627 		args[0] = progname;
628 		args[1] = buf;
629 		ipfw_main(2, args);
630 	}
631 	fclose(f);
632 	if (cmd != NULL) {
633 		int status;
634 
635 		if (waitpid(preproc, &status, 0) == -1)
636 			errx(EX_OSERR, "waitpid()");
637 		if (WIFEXITED(status) && WEXITSTATUS(status) != EX_OK)
638 			errx(EX_UNAVAILABLE,
639 			    "preprocessor exited with status %d",
640 			    WEXITSTATUS(status));
641 		else if (WIFSIGNALED(status))
642 			errx(EX_UNAVAILABLE,
643 			    "preprocessor exited with signal %d",
644 			    WTERMSIG(status));
645 	}
646 }
647 
648 int
main(int ac,char * av[])649 main(int ac, char *av[])
650 {
651 #if defined(_WIN32) && defined(TCC)
652 	{
653 		WSADATA wsaData;
654 		int ret=0;
655 		unsigned short wVersionRequested = MAKEWORD(2, 2);
656 		ret = WSAStartup(wVersionRequested, &wsaData);
657 		if (ret != 0) {
658 			/* Tell the user that we could not find a usable */
659 			/* Winsock DLL.				  */
660 			printf("WSAStartup failed with error: %d\n", ret);
661 			return 1;
662 		}
663 	}
664 #endif
665 
666 	if (strcmp(av[0], "dnctl") == 0)
667 		g_co.prog = cmdline_prog_dnctl;
668 	else
669 		g_co.prog = cmdline_prog_ipfw;
670 
671 	/*
672 	 * If the last argument is an absolute pathname, interpret it
673 	 * as a file to be preprocessed.
674 	 */
675 
676 	if (ac > 1 && av[ac - 1][0] == '/') {
677 		if (! is_ipfw())
678 			errx(EX_USAGE, "usage: dnctl [options]\n"
679 			    "do \"dnctl -h\" for details");
680 
681 		if (access(av[ac - 1], R_OK) == 0)
682 			ipfw_readfile(ac, av);
683 		else
684 			err(EX_USAGE, "pathname: %s", av[ac - 1]);
685 	} else {
686 		if (ipfw_main(ac, av)) {
687 			errx(EX_USAGE,
688 			    "usage: %s [options]\n"
689 			    "do \"%s -h\" or \"man %s\" for details", av[0],
690 			    av[0], av[0]);
691 		}
692 	}
693 	return EX_OK;
694 }
695