xref: /netbsd-src/external/bsd/file/dist/src/file.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: file.c,v 1.11 2018/04/18 01:18:16 christos Exp $	*/
2 
3 /*
4  * Copyright (c) Ian F. Darwin 1986-1995.
5  * Software written by Ian F. Darwin and others;
6  * maintained 1995-present by Christos Zoulas and others.
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  * 1. Redistributions of source code must retain the above copyright
12  *    notice immediately at the beginning of the file, without modification,
13  *    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 AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
22  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 /*
31  * file - find type of a file or files - main program.
32  */
33 
34 #include "file.h"
35 
36 #ifndef	lint
37 #if 0
38 FILE_RCSID("@(#)$File: file.c,v 1.175 2018/03/02 16:11:37 christos Exp $")
39 #else
40 __RCSID("$NetBSD: file.c,v 1.11 2018/04/18 01:18:16 christos Exp $");
41 #endif
42 #endif	/* lint */
43 
44 #include "magic.h"
45 
46 #include <stdlib.h>
47 #include <unistd.h>
48 #include <string.h>
49 #ifdef RESTORE_TIME
50 # if (__COHERENT__ >= 0x420)
51 #  include <sys/utime.h>
52 # else
53 #  ifdef USE_UTIMES
54 #   include <sys/time.h>
55 #  else
56 #   include <utime.h>
57 #  endif
58 # endif
59 #endif
60 #ifdef HAVE_UNISTD_H
61 #include <unistd.h>	/* for read() */
62 #endif
63 #ifdef HAVE_WCHAR_H
64 #include <wchar.h>
65 #endif
66 
67 #if defined(HAVE_GETOPT_H) && defined(HAVE_STRUCT_OPTION)
68 # include <getopt.h>
69 # ifndef HAVE_GETOPT_LONG
70 int getopt_long(int, char * const *, const char *,
71     const struct option *, int *);
72 # endif
73 # else
74 #  include "mygetopt.h"
75 #endif
76 
77 #ifdef S_IFLNK
78 # define IFLNK_h "h"
79 # define IFLNK_L "L"
80 #else
81 # define IFLNK_h ""
82 # define IFLNK_L ""
83 #endif
84 
85 #ifdef HAVE_LIBSECCOMP
86 # define SECCOMP_S "S"
87 #else
88 # define SECCOMP_S ""
89 #endif
90 
91 #define FILE_FLAGS	"bcCdE" IFLNK_h "ik" IFLNK_L "lNnprs" SECCOMP_S "vzZ0"
92 #define OPTSTRING	"bcCde:Ef:F:hiklLm:nNpP:rsSvzZ0"
93 
94 # define USAGE  \
95     "Usage: %s [-" FILE_FLAGS "] [--apple] [--extension] [--mime-encoding]\n" \
96     "            [--mime-type] [-e <testname>] [-F <separator>] " \
97     " [-f <namefile>]\n" \
98     "            [-m <magicfiles>] [-P <parameter=value>] <file> ...\n" \
99     "       %s -C [-m <magicfiles>]\n" \
100     "       %s [--help]\n"
101 
102 private int 		/* Global command-line options 		*/
103 	bflag = 0,	/* brief output format	 		*/
104 	nopad = 0,	/* Don't pad output			*/
105 	nobuffer = 0,   /* Do not buffer stdout 		*/
106 	nulsep = 0;	/* Append '\0' to the separator		*/
107 
108 private const char *separator = ":";	/* Default field separator	*/
109 private const struct option long_options[] = {
110 #define OPT_HELP		1
111 #define OPT_APPLE		2
112 #define OPT_EXTENSIONS		3
113 #define OPT_MIME_TYPE		4
114 #define OPT_MIME_ENCODING	5
115 #define OPT(shortname, longname, opt, def, doc)      \
116     {longname, opt, NULL, shortname},
117 #define OPT_LONGONLY(longname, opt, def, doc, id)        \
118     {longname, opt, NULL, id},
119 #include "file_opts.h"
120 #undef OPT
121 #undef OPT_LONGONLY
122     {0, 0, NULL, 0}
123     };
124 
125 private const struct {
126 	const char *name;
127 	int value;
128 } nv[] = {
129 	{ "apptype",	MAGIC_NO_CHECK_APPTYPE },
130 	{ "ascii",	MAGIC_NO_CHECK_ASCII },
131 	{ "cdf",	MAGIC_NO_CHECK_CDF },
132 	{ "compress",	MAGIC_NO_CHECK_COMPRESS },
133 	{ "elf",	MAGIC_NO_CHECK_ELF },
134 	{ "encoding",	MAGIC_NO_CHECK_ENCODING },
135 	{ "soft",	MAGIC_NO_CHECK_SOFT },
136 	{ "tar",	MAGIC_NO_CHECK_TAR },
137 	{ "text",	MAGIC_NO_CHECK_TEXT },	/* synonym for ascii */
138 	{ "tokens",	MAGIC_NO_CHECK_TOKENS }, /* OBSOLETE: ignored for backwards compatibility */
139 };
140 
141 private struct {
142 	const char *name;
143 	int tag;
144 	size_t value;
145 } pm[] = {
146 	{ "indir",	MAGIC_PARAM_INDIR_MAX, 0 },
147 	{ "name",	MAGIC_PARAM_NAME_MAX, 0 },
148 	{ "elf_phnum",	MAGIC_PARAM_ELF_PHNUM_MAX, 0 },
149 	{ "elf_shnum",	MAGIC_PARAM_ELF_SHNUM_MAX, 0 },
150 	{ "elf_notes",	MAGIC_PARAM_ELF_NOTES_MAX, 0 },
151 	{ "regex",	MAGIC_PARAM_REGEX_MAX, 0 },
152 	{ "bytes",	MAGIC_PARAM_BYTES_MAX, 0 },
153 };
154 
155 private int posixly;
156 
157 #ifdef __dead
158 __dead
159 #endif
160 private void usage(void);
161 private void docprint(const char *, int);
162 #ifdef __dead
163 __dead
164 #endif
165 private void help(void);
166 
167 private int unwrap(struct magic_set *, const char *);
168 private int process(struct magic_set *ms, const char *, int);
169 private struct magic_set *load(const char *, int);
170 private void setparam(const char *);
171 private void applyparam(magic_t);
172 
173 
174 /*
175  * main - parse arguments and handle options
176  */
177 int
178 main(int argc, char *argv[])
179 {
180 	int c;
181 	size_t i;
182 	int action = 0, didsomefiles = 0, errflg = 0;
183 	int flags = 0, e = 0;
184 #ifdef HAVE_LIBSECCOMP
185 	int sandbox = 1;
186 #endif
187 	struct magic_set *magic = NULL;
188 	int longindex;
189 	const char *magicfile = NULL;		/* where the magic is	*/
190 	char *progname;
191 
192 	/* makes islower etc work for other langs */
193 #ifdef HAVE_SETLOCALE
194 	(void)setlocale(LC_CTYPE, "");
195 #endif
196 
197 #ifdef __EMX__
198 	/* sh-like wildcard expansion! Shouldn't hurt at least ... */
199 	_wildcard(&argc, &argv);
200 #endif
201 
202 	if ((progname = strrchr(argv[0], '/')) != NULL)
203 		progname++;
204 	else
205 		progname = argv[0];
206 
207 	file_setprogname(progname);
208 
209 
210 #ifdef S_IFLNK
211 	posixly = getenv("POSIXLY_CORRECT") != NULL;
212 	flags |=  posixly ? MAGIC_SYMLINK : 0;
213 #endif
214 	while ((c = getopt_long(argc, argv, OPTSTRING, long_options,
215 	    &longindex)) != -1)
216 		switch (c) {
217 		case OPT_HELP:
218 			help();
219 			break;
220 		case OPT_APPLE:
221 			flags |= MAGIC_APPLE;
222 			break;
223 		case OPT_EXTENSIONS:
224 			flags |= MAGIC_EXTENSION;
225 			break;
226 		case OPT_MIME_TYPE:
227 			flags |= MAGIC_MIME_TYPE;
228 			break;
229 		case OPT_MIME_ENCODING:
230 			flags |= MAGIC_MIME_ENCODING;
231 			break;
232 		case '0':
233 			nulsep++;
234 			break;
235 		case 'b':
236 			bflag++;
237 			break;
238 		case 'c':
239 			action = FILE_CHECK;
240 			break;
241 		case 'C':
242 			action = FILE_COMPILE;
243 			break;
244 		case 'd':
245 			flags |= MAGIC_DEBUG|MAGIC_CHECK;
246 			break;
247 		case 'E':
248 			flags |= MAGIC_ERROR;
249 			break;
250 		case 'e':
251 			for (i = 0; i < sizeof(nv) / sizeof(nv[0]); i++)
252 				if (strcmp(nv[i].name, optarg) == 0)
253 					break;
254 
255 			if (i == sizeof(nv) / sizeof(nv[0]))
256 				errflg++;
257 			else
258 				flags |= nv[i].value;
259 			break;
260 
261 		case 'f':
262 			if(action)
263 				usage();
264 			if (magic == NULL)
265 				if ((magic = load(magicfile, flags)) == NULL)
266 					return 1;
267 			applyparam(magic);
268 			e |= unwrap(magic, optarg);
269 			++didsomefiles;
270 			break;
271 		case 'F':
272 			separator = optarg;
273 			break;
274 		case 'i':
275 			flags |= MAGIC_MIME;
276 			break;
277 		case 'k':
278 			flags |= MAGIC_CONTINUE;
279 			break;
280 		case 'l':
281 			action = FILE_LIST;
282 			break;
283 		case 'm':
284 			magicfile = optarg;
285 			break;
286 		case 'n':
287 			++nobuffer;
288 			break;
289 		case 'N':
290 			++nopad;
291 			break;
292 #if defined(HAVE_UTIME) || defined(HAVE_UTIMES)
293 		case 'p':
294 			flags |= MAGIC_PRESERVE_ATIME;
295 			break;
296 #endif
297 		case 'P':
298 			setparam(optarg);
299 			break;
300 		case 'r':
301 			flags |= MAGIC_RAW;
302 			break;
303 		case 's':
304 			flags |= MAGIC_DEVICES;
305 			break;
306 #ifdef HAVE_LIBSECCOMP
307 		case 'S':
308 			sandbox = 0;
309 			break;
310 #endif
311 		case 'v':
312 			if (magicfile == NULL)
313 				magicfile = magic_getpath(magicfile, action);
314 			(void)fprintf(stdout, "%s-%s\n", file_getprogname(),
315 			    VERSION);
316 			(void)fprintf(stdout, "magic file from %s\n",
317 			    magicfile);
318 			return 0;
319 		case 'z':
320 			flags |= MAGIC_COMPRESS;
321 			break;
322 
323 		case 'Z':
324 			flags |= MAGIC_COMPRESS|MAGIC_COMPRESS_TRANSP;
325 			break;
326 #ifdef S_IFLNK
327 		case 'L':
328 			flags |= MAGIC_SYMLINK;
329 			break;
330 		case 'h':
331 			flags &= ~MAGIC_SYMLINK;
332 			break;
333 #endif
334 		case '?':
335 		default:
336 			errflg++;
337 			break;
338 		}
339 
340 	if (errflg) {
341 		usage();
342 	}
343 	if (e)
344 		return e;
345 
346 #ifdef HAVE_LIBSECCOMP
347 #if 0
348 	if (sandbox && enable_sandbox_basic() == -1)
349 #else
350 	if (sandbox && enable_sandbox_full() == -1)
351 #endif
352 		file_err(EXIT_FAILURE, "SECCOMP initialisation failed");
353 #endif /* HAVE_LIBSECCOMP */
354 
355 	if (MAGIC_VERSION != magic_version())
356 		file_warnx("Compiled magic version [%d] "
357 		    "does not match with shared library magic version [%d]\n",
358 		    MAGIC_VERSION, magic_version());
359 
360 	switch(action) {
361 	case FILE_CHECK:
362 	case FILE_COMPILE:
363 	case FILE_LIST:
364 		/*
365 		 * Don't try to check/compile ~/.magic unless we explicitly
366 		 * ask for it.
367 		 */
368 		magic = magic_open(flags|MAGIC_CHECK);
369 		if (magic == NULL) {
370 			file_warn("Can't create magic");
371 			return 1;
372 		}
373 
374 
375 		switch(action) {
376 		case FILE_CHECK:
377 			c = magic_check(magic, magicfile);
378 			break;
379 		case FILE_COMPILE:
380 			c = magic_compile(magic, magicfile);
381 			break;
382 		case FILE_LIST:
383 			c = magic_list(magic, magicfile);
384 			break;
385 		default:
386 			abort();
387 		}
388 		if (c == -1) {
389 			file_warnx("%s", magic_error(magic));
390 			e = 1;
391 			goto out;
392 		}
393 		goto out;
394 	default:
395 		if (magic == NULL)
396 			if ((magic = load(magicfile, flags)) == NULL)
397 				return 1;
398 		applyparam(magic);
399 	}
400 
401 	if (optind == argc) {
402 		if (!didsomefiles)
403 			usage();
404 	}
405 	else {
406 		size_t j, wid, nw;
407 		for (wid = 0, j = (size_t)optind; j < (size_t)argc; j++) {
408 			nw = file_mbswidth(argv[j]);
409 			if (nw > wid)
410 				wid = nw;
411 		}
412 		/*
413 		 * If bflag is only set twice, set it depending on
414 		 * number of files [this is undocumented, and subject to change]
415 		 */
416 		if (bflag == 2) {
417 			bflag = optind >= argc - 1;
418 		}
419 		for (; optind < argc; optind++)
420 			e |= process(magic, argv[optind], wid);
421 	}
422 
423 out:
424 	if (magic)
425 		magic_close(magic);
426 	return e;
427 }
428 
429 private void
430 applyparam(magic_t magic)
431 {
432 	size_t i;
433 
434 	for (i = 0; i < __arraycount(pm); i++) {
435 		if (pm[i].value == 0)
436 			continue;
437 		if (magic_setparam(magic, pm[i].tag, &pm[i].value) == -1)
438 			file_err(EXIT_FAILURE, "Can't set %s", pm[i].name);
439 	}
440 }
441 
442 private void
443 setparam(const char *p)
444 {
445 	size_t i;
446 	char *s;
447 
448 	if ((s = strchr(p, '=')) == NULL)
449 		goto badparm;
450 
451 	for (i = 0; i < __arraycount(pm); i++) {
452 		if (strncmp(p, pm[i].name, s - p) != 0)
453 			continue;
454 		pm[i].value = atoi(s + 1);
455 		return;
456 	}
457 badparm:
458 	file_errx(EXIT_FAILURE, "Unknown param %s", p);
459 }
460 
461 private struct magic_set *
462 /*ARGSUSED*/
463 load(const char *magicfile, int flags)
464 {
465 	struct magic_set *magic = magic_open(flags);
466 	const char *e;
467 
468 	if (magic == NULL) {
469 		file_warn("Can't create magic");
470 		return NULL;
471 	}
472 	if (magic_load(magic, magicfile) == -1) {
473 		file_warn("%s", magic_error(magic));
474 		magic_close(magic);
475 		return NULL;
476 	}
477 	if ((e = magic_error(magic)) != NULL)
478 		file_warn("%s", e);
479 	return magic;
480 }
481 
482 /*
483  * unwrap -- read a file of filenames, do each one.
484  */
485 private int
486 unwrap(struct magic_set *ms, const char *fn)
487 {
488 	FILE *f;
489 	ssize_t len;
490 	char *line = NULL;
491 	size_t llen = 0;
492 	int wid = 0, cwid;
493 	int e = 0;
494 
495 	if (strcmp("-", fn) == 0) {
496 		f = stdin;
497 		wid = 1;
498 	} else {
499 		if ((f = fopen(fn, "r")) == NULL) {
500 			file_warn("Cannot open `%s'", fn);
501 			return 1;
502 		}
503 
504 		while ((len = getline(&line, &llen, f)) > 0) {
505 			if (line[len - 1] == '\n')
506 				line[len - 1] = '\0';
507 			cwid = file_mbswidth(line);
508 			if (cwid > wid)
509 				wid = cwid;
510 		}
511 
512 		rewind(f);
513 	}
514 
515 	while ((len = getline(&line, &llen, f)) > 0) {
516 		if (line[len - 1] == '\n')
517 			line[len - 1] = '\0';
518 		e |= process(ms, line, wid);
519 		if(nobuffer)
520 			(void)fflush(stdout);
521 	}
522 
523 	free(line);
524 	(void)fclose(f);
525 	return e;
526 }
527 
528 /*
529  * Called for each input file on the command line (or in a list of files)
530  */
531 private int
532 process(struct magic_set *ms, const char *inname, int wid)
533 {
534 	const char *type, c = nulsep > 1 ? '\0' : '\n';
535 	int std_in = strcmp(inname, "-") == 0;
536 
537 	if (wid > 0 && !bflag) {
538 		(void)printf("%s", std_in ? "/dev/stdin" : inname);
539 		if (nulsep)
540 			(void)putc('\0', stdout);
541 		if (nulsep < 2) {
542 			(void)printf("%s", separator);
543 			(void)printf("%*s ",
544 			    (int) (nopad ? 0 : (wid - file_mbswidth(inname))),
545 			    "");
546 		}
547 	}
548 
549 	type = magic_file(ms, std_in ? NULL : inname);
550 
551 	if (type == NULL) {
552 		(void)printf("ERROR: %s%c", magic_error(ms), c);
553 		return 1;
554 	} else {
555 		(void)printf("%s%c", type, c);
556 		return 0;
557 	}
558 }
559 
560 protected size_t
561 file_mbswidth(const char *s)
562 {
563 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
564 	size_t bytesconsumed, old_n, n, width = 0;
565 	mbstate_t state;
566 	wchar_t nextchar;
567 	(void)memset(&state, 0, sizeof(mbstate_t));
568 	old_n = n = strlen(s);
569 
570 	while (n > 0) {
571 		bytesconsumed = mbrtowc(&nextchar, s, n, &state);
572 		if (bytesconsumed == (size_t)(-1) ||
573 		    bytesconsumed == (size_t)(-2)) {
574 			/* Something went wrong, return something reasonable */
575 			return old_n;
576 		}
577 		if (s[0] == '\n') {
578 			/*
579 			 * do what strlen() would do, so that caller
580 			 * is always right
581 			 */
582 			width++;
583 		} else {
584 			int w = wcwidth(nextchar);
585 			if (w > 0)
586 				width += w;
587 		}
588 
589 		s += bytesconsumed, n -= bytesconsumed;
590 	}
591 	return width;
592 #else
593 	return strlen(s);
594 #endif
595 }
596 
597 private void
598 usage(void)
599 {
600 	const char *pn = file_getprogname();
601 	(void)fprintf(stderr, USAGE, pn, pn, pn);
602 	exit(EXIT_FAILURE);
603 }
604 
605 private void
606 defprint(int def)
607 {
608 	if (!def)
609 		return;
610 	if (((def & 1) && posixly) || ((def & 2) && !posixly))
611 		fprintf(stdout, " (default)");
612 	fputc('\n', stdout);
613 }
614 
615 private void
616 docprint(const char *opts, int def)
617 {
618 	size_t i;
619 	int comma;
620 	char *sp, *p;
621 
622 	p = strstr(opts, "%o");
623 	if (p == NULL) {
624 		fprintf(stdout, "%s", opts);
625 		defprint(def);
626 		return;
627 	}
628 
629 	for (sp = p - 1; sp > opts && *sp == ' '; sp--)
630 		continue;
631 
632 	fprintf(stdout, "%.*s", (int)(p - opts), opts);
633 
634 	comma = 0;
635 	for (i = 0; i < __arraycount(nv); i++) {
636 		fprintf(stdout, "%s%s", comma++ ? ", " : "", nv[i].name);
637 		if (i && i % 5 == 0) {
638 			fprintf(stdout, ",\n%*s", (int)(p - sp - 1), "");
639 			comma = 0;
640 		}
641 	}
642 
643 	fprintf(stdout, "%s", opts + (p - opts) + 2);
644 }
645 
646 private void
647 help(void)
648 {
649 	(void)fputs(
650 "Usage: file [OPTION...] [FILE...]\n"
651 "Determine type of FILEs.\n"
652 "\n", stdout);
653 #define OPT(shortname, longname, opt, def, doc)      \
654 	fprintf(stdout, "  -%c, --" longname, shortname), \
655 	docprint(doc, def);
656 #define OPT_LONGONLY(longname, opt, def, doc, id)        \
657 	fprintf(stdout, "      --" longname),	\
658 	docprint(doc, def);
659 #include "file_opts.h"
660 #undef OPT
661 #undef OPT_LONGONLY
662 	fprintf(stdout, "\nReport bugs to http://bugs.gw.com/\n");
663 	exit(EXIT_SUCCESS);
664 }
665 
666 private const char *file_progname;
667 
668 protected void
669 file_setprogname(const char *progname)
670 {
671 	file_progname = progname;
672 }
673 
674 protected const char *
675 file_getprogname(void)
676 {
677 	return file_progname;
678 }
679 
680 protected void
681 file_err(int e, const char *fmt, ...)
682 {
683 	va_list ap;
684 	int se = errno;
685 
686 	va_start(ap, fmt);
687 	fprintf(stderr, "%s: ", file_progname);
688 	vfprintf(stderr, fmt, ap);
689 	va_end(ap);
690 	fprintf(stderr, " (%s)\n", strerror(se));
691 	exit(e);
692 }
693 
694 protected void
695 file_errx(int e, const char *fmt, ...)
696 {
697 	va_list ap;
698 
699 	va_start(ap, fmt);
700 	fprintf(stderr, "%s: ", file_progname);
701 	vfprintf(stderr, fmt, ap);
702 	va_end(ap);
703 	fprintf(stderr, "\n");
704 	exit(e);
705 }
706 
707 protected void
708 file_warn(const char *fmt, ...)
709 {
710 	va_list ap;
711 	int se = errno;
712 
713 	va_start(ap, fmt);
714 	fprintf(stderr, "%s: ", file_progname);
715 	vfprintf(stderr, fmt, ap);
716 	va_end(ap);
717 	fprintf(stderr, " (%s)\n", strerror(se));
718 	errno = se;
719 }
720 
721 protected void
722 file_warnx(const char *fmt, ...)
723 {
724 	va_list ap;
725 	int se = errno;
726 
727 	va_start(ap, fmt);
728 	fprintf(stderr, "%s: ", file_progname);
729 	vfprintf(stderr, fmt, ap);
730 	va_end(ap);
731 	fprintf(stderr, "\n");
732 	errno = se;
733 }
734