xref: /netbsd-src/external/bsd/file/dist/src/file.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: file.c,v 1.13 2019/05/22 17:26:05 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 1.181 2019/03/28 20:54:03 christos Exp $")
39 #else
40 __RCSID("$NetBSD: file.c,v 1.13 2019/05/22 17:26:05 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 	{ "json",	MAGIC_NO_CHECK_JSON },
138 	{ "text",	MAGIC_NO_CHECK_TEXT },	/* synonym for ascii */
139 	{ "tokens",	MAGIC_NO_CHECK_TOKENS }, /* OBSOLETE: ignored for backwards compatibility */
140 };
141 
142 private struct {
143 	const char *name;
144 	int tag;
145 	size_t value;
146 	int set;
147 } pm[] = {
148 	{ "indir",	MAGIC_PARAM_INDIR_MAX, 0, 0 },
149 	{ "name",	MAGIC_PARAM_NAME_MAX, 0, 0 },
150 	{ "elf_phnum",	MAGIC_PARAM_ELF_PHNUM_MAX, 0, 0 },
151 	{ "elf_shnum",	MAGIC_PARAM_ELF_SHNUM_MAX, 0, 0 },
152 	{ "elf_notes",	MAGIC_PARAM_ELF_NOTES_MAX, 0, 0 },
153 	{ "regex",	MAGIC_PARAM_REGEX_MAX, 0, 0 },
154 	{ "bytes",	MAGIC_PARAM_BYTES_MAX, 0, 0 },
155 };
156 
157 private int posixly;
158 
159 #ifdef __dead
160 __dead
161 #endif
162 private void usage(void);
163 private void docprint(const char *, int);
164 #ifdef __dead
165 __dead
166 #endif
167 private void help(void);
168 
169 private int unwrap(struct magic_set *, const char *);
170 private int process(struct magic_set *ms, const char *, int);
171 private struct magic_set *load(const char *, int);
172 private void setparam(const char *);
173 private void applyparam(magic_t);
174 
175 
176 /*
177  * main - parse arguments and handle options
178  */
179 int
180 main(int argc, char *argv[])
181 {
182 	int c;
183 	size_t i;
184 	int action = 0, didsomefiles = 0, errflg = 0;
185 	int flags = 0, e = 0;
186 #ifdef HAVE_LIBSECCOMP
187 	int sandbox = 1;
188 #endif
189 	struct magic_set *magic = NULL;
190 	int longindex;
191 	const char *magicfile = NULL;		/* where the magic is	*/
192 	char *progname;
193 
194 	/* makes islower etc work for other langs */
195 	(void)setlocale(LC_CTYPE, "");
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 < __arraycount(nv); i++)
252 				if (strcmp(nv[i].name, optarg) == 0)
253 					break;
254 
255 			if (i == __arraycount(nv))
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 = CAST(size_t, optind); j < CAST(size_t, argc);
408 		    j++) {
409 			nw = file_mbswidth(argv[j]);
410 			if (nw > wid)
411 				wid = nw;
412 		}
413 		/*
414 		 * If bflag is only set twice, set it depending on
415 		 * number of files [this is undocumented, and subject to change]
416 		 */
417 		if (bflag == 2) {
418 			bflag = optind >= argc - 1;
419 		}
420 		for (; optind < argc; optind++)
421 			e |= process(magic, argv[optind], wid);
422 	}
423 
424 out:
425 	if (magic)
426 		magic_close(magic);
427 	return e;
428 }
429 
430 private void
431 applyparam(magic_t magic)
432 {
433 	size_t i;
434 
435 	for (i = 0; i < __arraycount(pm); i++) {
436 		if (!pm[i].set)
437 			continue;
438 		if (magic_setparam(magic, pm[i].tag, &pm[i].value) == -1)
439 			file_err(EXIT_FAILURE, "Can't set %s", pm[i].name);
440 	}
441 }
442 
443 private void
444 setparam(const char *p)
445 {
446 	size_t i;
447 	char *s;
448 
449 	if ((s = strchr(p, '=')) == NULL)
450 		goto badparm;
451 
452 	for (i = 0; i < __arraycount(pm); i++) {
453 		if (strncmp(p, pm[i].name, s - p) != 0)
454 			continue;
455 		pm[i].value = atoi(s + 1);
456 		pm[i].set = 1;
457 		return;
458 	}
459 badparm:
460 	file_errx(EXIT_FAILURE, "Unknown param %s", p);
461 }
462 
463 private struct magic_set *
464 /*ARGSUSED*/
465 load(const char *magicfile, int flags)
466 {
467 	struct magic_set *magic = magic_open(flags);
468 	const char *e;
469 
470 	if (magic == NULL) {
471 		file_warn("Can't create magic");
472 		return NULL;
473 	}
474 	if (magic_load(magic, magicfile) == -1) {
475 		file_warn("%s", magic_error(magic));
476 		magic_close(magic);
477 		return NULL;
478 	}
479 	if ((e = magic_error(magic)) != NULL)
480 		file_warn("%s", e);
481 	return magic;
482 }
483 
484 /*
485  * unwrap -- read a file of filenames, do each one.
486  */
487 private int
488 unwrap(struct magic_set *ms, const char *fn)
489 {
490 	FILE *f;
491 	ssize_t len;
492 	char *line = NULL;
493 	size_t llen = 0;
494 	int wid = 0, cwid;
495 	int e = 0;
496 
497 	if (strcmp("-", fn) == 0) {
498 		f = stdin;
499 		wid = 1;
500 	} else {
501 		if ((f = fopen(fn, "r")) == NULL) {
502 			file_warn("Cannot open `%s'", fn);
503 			return 1;
504 		}
505 
506 		while ((len = getline(&line, &llen, f)) > 0) {
507 			if (line[len - 1] == '\n')
508 				line[len - 1] = '\0';
509 			cwid = file_mbswidth(line);
510 			if (cwid > wid)
511 				wid = cwid;
512 		}
513 
514 		rewind(f);
515 	}
516 
517 	while ((len = getline(&line, &llen, f)) > 0) {
518 		if (line[len - 1] == '\n')
519 			line[len - 1] = '\0';
520 		e |= process(ms, line, wid);
521 		if(nobuffer)
522 			(void)fflush(stdout);
523 	}
524 
525 	free(line);
526 	(void)fclose(f);
527 	return e;
528 }
529 
530 /*
531  * Called for each input file on the command line (or in a list of files)
532  */
533 private int
534 process(struct magic_set *ms, const char *inname, int wid)
535 {
536 	const char *type, c = nulsep > 1 ? '\0' : '\n';
537 	int std_in = strcmp(inname, "-") == 0;
538 
539 	if (wid > 0 && !bflag) {
540 		(void)printf("%s", std_in ? "/dev/stdin" : inname);
541 		if (nulsep)
542 			(void)putc('\0', stdout);
543 		if (nulsep < 2) {
544 			(void)printf("%s", separator);
545 			(void)printf("%*s ", CAST(int, nopad ? 0
546 			    : (wid - file_mbswidth(inname))), "");
547 		}
548 	}
549 
550 	type = magic_file(ms, std_in ? NULL : inname);
551 
552 	if (type == NULL) {
553 		(void)printf("ERROR: %s%c", magic_error(ms), c);
554 		return 1;
555 	} else {
556 		(void)printf("%s%c", type, c);
557 		return 0;
558 	}
559 }
560 
561 protected size_t
562 file_mbswidth(const char *s)
563 {
564 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
565 	size_t bytesconsumed, old_n, n, width = 0;
566 	mbstate_t state;
567 	wchar_t nextchar;
568 	(void)memset(&state, 0, sizeof(mbstate_t));
569 	old_n = n = strlen(s);
570 
571 	while (n > 0) {
572 		bytesconsumed = mbrtowc(&nextchar, s, n, &state);
573 		if (bytesconsumed == CAST(size_t, -1) ||
574 		    bytesconsumed == CAST(size_t, -2)) {
575 			/* Something went wrong, return something reasonable */
576 			return old_n;
577 		}
578 		if (s[0] == '\n') {
579 			/*
580 			 * do what strlen() would do, so that caller
581 			 * is always right
582 			 */
583 			width++;
584 		} else {
585 			int w = wcwidth(nextchar);
586 			if (w > 0)
587 				width += w;
588 		}
589 
590 		s += bytesconsumed, n -= bytesconsumed;
591 	}
592 	return width;
593 #else
594 	return strlen(s);
595 #endif
596 }
597 
598 private void
599 usage(void)
600 {
601 	const char *pn = file_getprogname();
602 	(void)fprintf(stderr, USAGE, pn, pn, pn);
603 	exit(EXIT_FAILURE);
604 }
605 
606 private void
607 defprint(int def)
608 {
609 	if (!def)
610 		return;
611 	if (((def & 1) && posixly) || ((def & 2) && !posixly))
612 		fprintf(stdout, " (default)");
613 	fputc('\n', stdout);
614 }
615 
616 private void
617 docprint(const char *opts, int def)
618 {
619 	size_t i;
620 	int comma;
621 	char *sp, *p;
622 
623 	p = strstr(opts, "%o");
624 	if (p == NULL) {
625 		fprintf(stdout, "%s", opts);
626 		defprint(def);
627 		return;
628 	}
629 
630 	for (sp = p - 1; sp > opts && *sp == ' '; sp--)
631 		continue;
632 
633 	fprintf(stdout, "%.*s", CAST(int, p - opts), opts);
634 
635 	comma = 0;
636 	for (i = 0; i < __arraycount(nv); i++) {
637 		fprintf(stdout, "%s%s", comma++ ? ", " : "", nv[i].name);
638 		if (i && i % 5 == 0 && i != __arraycount(nv) - 1) {
639 			fprintf(stdout, ",\n%*s", CAST(int, p - sp - 1), "");
640 			comma = 0;
641 		}
642 	}
643 
644 	fprintf(stdout, "%s", opts + (p - opts) + 2);
645 }
646 
647 private void
648 help(void)
649 {
650 	(void)fputs(
651 "Usage: file [OPTION...] [FILE...]\n"
652 "Determine type of FILEs.\n"
653 "\n", stdout);
654 #define OPT(shortname, longname, opt, def, doc)      \
655 	fprintf(stdout, "  -%c, --" longname, shortname), \
656 	docprint(doc, def);
657 #define OPT_LONGONLY(longname, opt, def, doc, id)        \
658 	fprintf(stdout, "      --" longname),	\
659 	docprint(doc, def);
660 #include "file_opts.h"
661 #undef OPT
662 #undef OPT_LONGONLY
663 	fprintf(stdout, "\nReport bugs to https://bugs.astron.com/\n");
664 	exit(EXIT_SUCCESS);
665 }
666 
667 private const char *file_progname;
668 
669 protected void
670 file_setprogname(const char *progname)
671 {
672 	file_progname = progname;
673 }
674 
675 protected const char *
676 file_getprogname(void)
677 {
678 	return file_progname;
679 }
680 
681 protected void
682 file_err(int e, const char *fmt, ...)
683 {
684 	va_list ap;
685 	int se = errno;
686 
687 	va_start(ap, fmt);
688 	fprintf(stderr, "%s: ", file_progname);
689 	vfprintf(stderr, fmt, ap);
690 	va_end(ap);
691 	fprintf(stderr, " (%s)\n", strerror(se));
692 	exit(e);
693 }
694 
695 protected void
696 file_errx(int e, const char *fmt, ...)
697 {
698 	va_list ap;
699 
700 	va_start(ap, fmt);
701 	fprintf(stderr, "%s: ", file_progname);
702 	vfprintf(stderr, fmt, ap);
703 	va_end(ap);
704 	fprintf(stderr, "\n");
705 	exit(e);
706 }
707 
708 protected void
709 file_warn(const char *fmt, ...)
710 {
711 	va_list ap;
712 	int se = errno;
713 
714 	va_start(ap, fmt);
715 	fprintf(stderr, "%s: ", file_progname);
716 	vfprintf(stderr, fmt, ap);
717 	va_end(ap);
718 	fprintf(stderr, " (%s)\n", strerror(se));
719 	errno = se;
720 }
721 
722 protected void
723 file_warnx(const char *fmt, ...)
724 {
725 	va_list ap;
726 	int se = errno;
727 
728 	va_start(ap, fmt);
729 	fprintf(stderr, "%s: ", file_progname);
730 	vfprintf(stderr, fmt, ap);
731 	va_end(ap);
732 	fprintf(stderr, "\n");
733 	errno = se;
734 }
735