xref: /freebsd/contrib/file/src/apprentice.c (revision 898496ee)
1 /*
2  * Copyright (c) Ian F. Darwin 1986-1995.
3  * Software written by Ian F. Darwin and others;
4  * maintained 1995-present by Christos Zoulas and others.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice immediately at the beginning of the file, without modification,
11  *    this list of conditions, and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 /*
29  * apprentice - make one pass through /etc/magic, learning its secrets.
30  */
31 
32 #include "file.h"
33 
34 #ifndef	lint
35 FILE_RCSID("@(#)$File: apprentice.c,v 1.342 2023/07/17 14:38:35 christos Exp $")
36 #endif	/* lint */
37 
38 #include "magic.h"
39 #include <stdlib.h>
40 #ifdef HAVE_UNISTD_H
41 #include <unistd.h>
42 #endif
43 #include <stddef.h>
44 #include <string.h>
45 #include <assert.h>
46 #include <ctype.h>
47 #include <fcntl.h>
48 #ifdef QUICK
49 #include <sys/mman.h>
50 #endif
51 #include <dirent.h>
52 #include <limits.h>
53 #ifdef HAVE_BYTESWAP_H
54 #include <byteswap.h>
55 #endif
56 #ifdef HAVE_SYS_BSWAP_H
57 #include <sys/bswap.h>
58 #endif
59 
60 
61 #define	EATAB {while (isascii(CAST(unsigned char, *l)) && \
62 		      isspace(CAST(unsigned char, *l)))  ++l;}
63 #define LOWCASE(l) (isupper(CAST(unsigned char, l)) ? \
64 			tolower(CAST(unsigned char, l)) : (l))
65 /*
66  * Work around a bug in headers on Digital Unix.
67  * At least confirmed for: OSF1 V4.0 878
68  */
69 #if defined(__osf__) && defined(__DECC)
70 #ifdef MAP_FAILED
71 #undef MAP_FAILED
72 #endif
73 #endif
74 
75 #ifndef MAP_FAILED
76 #define MAP_FAILED (void *) -1
77 #endif
78 
79 #ifndef MAP_FILE
80 #define MAP_FILE 0
81 #endif
82 
83 #define ALLOC_CHUNK	CAST(size_t, 10)
84 #define ALLOC_INCR	CAST(size_t, 200)
85 
86 #define MAP_TYPE_USER	0
87 #define MAP_TYPE_MALLOC	1
88 #define MAP_TYPE_MMAP	2
89 
90 struct magic_entry {
91 	struct magic *mp;
92 	uint32_t cont_count;
93 	uint32_t max_count;
94 };
95 
96 struct magic_entry_set {
97 	struct magic_entry *me;
98 	uint32_t count;
99 	uint32_t max;
100 };
101 
102 struct magic_map {
103 	void *p;
104 	size_t len;
105 	int type;
106 	struct magic *magic[MAGIC_SETS];
107 	uint32_t nmagic[MAGIC_SETS];
108 };
109 
110 int file_formats[FILE_NAMES_SIZE];
111 const size_t file_nformats = FILE_NAMES_SIZE;
112 const char *file_names[FILE_NAMES_SIZE];
113 const size_t file_nnames = FILE_NAMES_SIZE;
114 
115 file_private int getvalue(struct magic_set *ms, struct magic *, const char **, int);
116 file_private int hextoint(int);
117 file_private const char *getstr(struct magic_set *, struct magic *, const char *,
118     int);
119 file_private int parse(struct magic_set *, struct magic_entry *, const char *,
120     size_t, int);
121 file_private void eatsize(const char **);
122 file_private int apprentice_1(struct magic_set *, const char *, int);
123 file_private ssize_t apprentice_magic_strength_1(const struct magic *);
124 file_private int apprentice_sort(const void *, const void *);
125 file_private void apprentice_list(struct mlist *, int );
126 file_private struct magic_map *apprentice_load(struct magic_set *,
127     const char *, int);
128 file_private struct mlist *mlist_alloc(void);
129 file_private void mlist_free_all(struct magic_set *);
130 file_private void mlist_free(struct mlist *);
131 file_private void byteswap(struct magic *, uint32_t);
132 file_private void bs1(struct magic *);
133 
134 #if defined(HAVE_BYTESWAP_H)
135 #define swap2(x)	bswap_16(x)
136 #define swap4(x)	bswap_32(x)
137 #define swap8(x)	bswap_64(x)
138 #elif defined(HAVE_SYS_BSWAP_H)
139 #define swap2(x)	bswap16(x)
140 #define swap4(x)	bswap32(x)
141 #define swap8(x)	bswap64(x)
142 #else
143 file_private uint16_t swap2(uint16_t);
144 file_private uint32_t swap4(uint32_t);
145 file_private uint64_t swap8(uint64_t);
146 #endif
147 
148 file_private char *mkdbname(struct magic_set *, const char *, int);
149 file_private struct magic_map *apprentice_buf(struct magic_set *, struct magic *,
150     size_t);
151 file_private struct magic_map *apprentice_map(struct magic_set *, const char *);
152 file_private int check_buffer(struct magic_set *, struct magic_map *, const char *);
153 file_private void apprentice_unmap(struct magic_map *);
154 file_private int apprentice_compile(struct magic_set *, struct magic_map *,
155     const char *);
156 file_private int check_format_type(const char *, int, const char **);
157 file_private int check_format(struct magic_set *, struct magic *);
158 file_private int get_op(char);
159 file_private int parse_mime(struct magic_set *, struct magic_entry *, const char *,
160     size_t);
161 file_private int parse_strength(struct magic_set *, struct magic_entry *,
162     const char *, size_t);
163 file_private int parse_apple(struct magic_set *, struct magic_entry *, const char *,
164     size_t);
165 file_private int parse_ext(struct magic_set *, struct magic_entry *, const char *,
166     size_t);
167 
168 
169 file_private size_t magicsize = sizeof(struct magic);
170 
171 file_private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
172 
173 file_private struct {
174 	const char *name;
175 	size_t len;
176 	int (*fun)(struct magic_set *, struct magic_entry *, const char *,
177 	    size_t);
178 } bang[] = {
179 #define	DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
180 	DECLARE_FIELD(mime),
181 	DECLARE_FIELD(apple),
182 	DECLARE_FIELD(ext),
183 	DECLARE_FIELD(strength),
184 #undef	DECLARE_FIELD
185 	{ NULL, 0, NULL }
186 };
187 
188 #ifdef COMPILE_ONLY
189 
190 int main(int, char *[]);
191 
192 int
main(int argc,char * argv[])193 main(int argc, char *argv[])
194 {
195 	int ret;
196 	struct magic_set *ms;
197 	char *progname;
198 
199 	if ((progname = strrchr(argv[0], '/')) != NULL)
200 		progname++;
201 	else
202 		progname = argv[0];
203 
204 	if (argc != 2) {
205 		(void)fprintf(stderr, "Usage: %s file\n", progname);
206 		return 1;
207 	}
208 
209 	if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
210 		(void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
211 		return 1;
212 	}
213 	ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
214 	if (ret == 1)
215 		(void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
216 	magic_close(ms);
217 	return ret;
218 }
219 #endif /* COMPILE_ONLY */
220 
221 struct type_tbl_s {
222 	const char name[16];
223 	const size_t len;
224 	const int type;
225 	const int format;
226 };
227 
228 /*
229  * XXX - the actual Single UNIX Specification says that "long" means "long",
230  * as in the C data type, but we treat it as meaning "4-byte integer".
231  * Given that the OS X version of file 5.04 did the same, I guess that passes
232  * the actual test; having "long" be dependent on how big a "long" is on
233  * the machine running "file" is silly.
234  */
235 static const struct type_tbl_s type_tbl[] = {
236 # define XX(s)		s, (sizeof(s) - 1)
237 # define XX_NULL	"", 0
238 	{ XX("invalid"),	FILE_INVALID,		FILE_FMT_NONE },
239 	{ XX("byte"),		FILE_BYTE,		FILE_FMT_NUM },
240 	{ XX("short"),		FILE_SHORT,		FILE_FMT_NUM },
241 	{ XX("default"),	FILE_DEFAULT,		FILE_FMT_NONE },
242 	{ XX("long"),		FILE_LONG,		FILE_FMT_NUM },
243 	{ XX("string"),		FILE_STRING,		FILE_FMT_STR },
244 	{ XX("date"),		FILE_DATE,		FILE_FMT_STR },
245 	{ XX("beshort"),	FILE_BESHORT,		FILE_FMT_NUM },
246 	{ XX("belong"),		FILE_BELONG,		FILE_FMT_NUM },
247 	{ XX("bedate"),		FILE_BEDATE,		FILE_FMT_STR },
248 	{ XX("leshort"),	FILE_LESHORT,		FILE_FMT_NUM },
249 	{ XX("lelong"),		FILE_LELONG,		FILE_FMT_NUM },
250 	{ XX("ledate"),		FILE_LEDATE,		FILE_FMT_STR },
251 	{ XX("pstring"),	FILE_PSTRING,		FILE_FMT_STR },
252 	{ XX("ldate"),		FILE_LDATE,		FILE_FMT_STR },
253 	{ XX("beldate"),	FILE_BELDATE,		FILE_FMT_STR },
254 	{ XX("leldate"),	FILE_LELDATE,		FILE_FMT_STR },
255 	{ XX("regex"),		FILE_REGEX,		FILE_FMT_STR },
256 	{ XX("bestring16"),	FILE_BESTRING16,	FILE_FMT_STR },
257 	{ XX("lestring16"),	FILE_LESTRING16,	FILE_FMT_STR },
258 	{ XX("search"),		FILE_SEARCH,		FILE_FMT_STR },
259 	{ XX("medate"),		FILE_MEDATE,		FILE_FMT_STR },
260 	{ XX("meldate"),	FILE_MELDATE,		FILE_FMT_STR },
261 	{ XX("melong"),		FILE_MELONG,		FILE_FMT_NUM },
262 	{ XX("quad"),		FILE_QUAD,		FILE_FMT_QUAD },
263 	{ XX("lequad"),		FILE_LEQUAD,		FILE_FMT_QUAD },
264 	{ XX("bequad"),		FILE_BEQUAD,		FILE_FMT_QUAD },
265 	{ XX("qdate"),		FILE_QDATE,		FILE_FMT_STR },
266 	{ XX("leqdate"),	FILE_LEQDATE,		FILE_FMT_STR },
267 	{ XX("beqdate"),	FILE_BEQDATE,		FILE_FMT_STR },
268 	{ XX("qldate"),		FILE_QLDATE,		FILE_FMT_STR },
269 	{ XX("leqldate"),	FILE_LEQLDATE,		FILE_FMT_STR },
270 	{ XX("beqldate"),	FILE_BEQLDATE,		FILE_FMT_STR },
271 	{ XX("float"),		FILE_FLOAT,		FILE_FMT_FLOAT },
272 	{ XX("befloat"),	FILE_BEFLOAT,		FILE_FMT_FLOAT },
273 	{ XX("lefloat"),	FILE_LEFLOAT,		FILE_FMT_FLOAT },
274 	{ XX("double"),		FILE_DOUBLE,		FILE_FMT_DOUBLE },
275 	{ XX("bedouble"),	FILE_BEDOUBLE,		FILE_FMT_DOUBLE },
276 	{ XX("ledouble"),	FILE_LEDOUBLE,		FILE_FMT_DOUBLE },
277 	{ XX("leid3"),		FILE_LEID3,		FILE_FMT_NUM },
278 	{ XX("beid3"),		FILE_BEID3,		FILE_FMT_NUM },
279 	{ XX("indirect"),	FILE_INDIRECT,		FILE_FMT_NUM },
280 	{ XX("qwdate"),		FILE_QWDATE,		FILE_FMT_STR },
281 	{ XX("leqwdate"),	FILE_LEQWDATE,		FILE_FMT_STR },
282 	{ XX("beqwdate"),	FILE_BEQWDATE,		FILE_FMT_STR },
283 	{ XX("name"),		FILE_NAME,		FILE_FMT_NONE },
284 	{ XX("use"),		FILE_USE,		FILE_FMT_NONE },
285 	{ XX("clear"),		FILE_CLEAR,		FILE_FMT_NONE },
286 	{ XX("der"),		FILE_DER,		FILE_FMT_STR },
287 	{ XX("guid"),		FILE_GUID,		FILE_FMT_STR },
288 	{ XX("offset"),		FILE_OFFSET,		FILE_FMT_QUAD },
289 	{ XX("bevarint"),	FILE_BEVARINT,		FILE_FMT_STR },
290 	{ XX("levarint"),	FILE_LEVARINT,		FILE_FMT_STR },
291 	{ XX("msdosdate"),	FILE_MSDOSDATE,		FILE_FMT_STR },
292 	{ XX("lemsdosdate"),	FILE_LEMSDOSDATE,	FILE_FMT_STR },
293 	{ XX("bemsdosdate"),	FILE_BEMSDOSDATE,	FILE_FMT_STR },
294 	{ XX("msdostime"),	FILE_MSDOSTIME,		FILE_FMT_STR },
295 	{ XX("lemsdostime"),	FILE_LEMSDOSTIME,	FILE_FMT_STR },
296 	{ XX("bemsdostime"),	FILE_BEMSDOSTIME,	FILE_FMT_STR },
297 	{ XX("octal"),		FILE_OCTAL,		FILE_FMT_STR },
298 	{ XX_NULL,		FILE_INVALID,		FILE_FMT_NONE },
299 };
300 
301 /*
302  * These are not types, and cannot be preceded by "u" to make them
303  * unsigned.
304  */
305 static const struct type_tbl_s special_tbl[] = {
306 	{ XX("der"),		FILE_DER,		FILE_FMT_STR },
307 	{ XX("name"),		FILE_NAME,		FILE_FMT_STR },
308 	{ XX("use"),		FILE_USE,		FILE_FMT_STR },
309 	{ XX("octal"),		FILE_OCTAL,		FILE_FMT_STR },
310 	{ XX_NULL,		FILE_INVALID,		FILE_FMT_NONE },
311 };
312 # undef XX
313 # undef XX_NULL
314 
315 file_private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)316 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
317 {
318 	const struct type_tbl_s *p;
319 
320 	for (p = tbl; p->len; p++) {
321 		if (strncmp(l, p->name, p->len) == 0) {
322 			if (t)
323 				*t = l + p->len;
324 			break;
325 		}
326 	}
327 	return p->type;
328 }
329 
330 file_private off_t
maxoff_t(void)331 maxoff_t(void) {
332 	if (/*CONSTCOND*/sizeof(off_t) == sizeof(int))
333 		return CAST(off_t, INT_MAX);
334 	if (/*CONSTCOND*/sizeof(off_t) == sizeof(long))
335 		return CAST(off_t, LONG_MAX);
336 	return 0x7fffffff;
337 }
338 
339 file_private int
get_standard_integer_type(const char * l,const char ** t)340 get_standard_integer_type(const char *l, const char **t)
341 {
342 	int type;
343 
344 	if (isalpha(CAST(unsigned char, l[1]))) {
345 		switch (l[1]) {
346 		case 'C':
347 			/* "dC" and "uC" */
348 			type = FILE_BYTE;
349 			break;
350 		case 'S':
351 			/* "dS" and "uS" */
352 			type = FILE_SHORT;
353 			break;
354 		case 'I':
355 		case 'L':
356 			/*
357 			 * "dI", "dL", "uI", and "uL".
358 			 *
359 			 * XXX - the actual Single UNIX Specification says
360 			 * that "L" means "long", as in the C data type,
361 			 * but we treat it as meaning "4-byte integer".
362 			 * Given that the OS X version of file 5.04 did
363 			 * the same, I guess that passes the actual SUS
364 			 * validation suite; having "dL" be dependent on
365 			 * how big a "long" is on the machine running
366 			 * "file" is silly.
367 			 */
368 			type = FILE_LONG;
369 			break;
370 		case 'Q':
371 			/* "dQ" and "uQ" */
372 			type = FILE_QUAD;
373 			break;
374 		default:
375 			/* "d{anything else}", "u{anything else}" */
376 			return FILE_INVALID;
377 		}
378 		l += 2;
379 	} else if (isdigit(CAST(unsigned char, l[1]))) {
380 		/*
381 		 * "d{num}" and "u{num}"; we only support {num} values
382 		 * of 1, 2, 4, and 8 - the Single UNIX Specification
383 		 * doesn't say anything about whether arbitrary
384 		 * values should be supported, but both the Solaris 10
385 		 * and OS X Mountain Lion versions of file passed the
386 		 * Single UNIX Specification validation suite, and
387 		 * neither of them support values bigger than 8 or
388 		 * non-power-of-2 values.
389 		 */
390 		if (isdigit(CAST(unsigned char, l[2]))) {
391 			/* Multi-digit, so > 9 */
392 			return FILE_INVALID;
393 		}
394 		switch (l[1]) {
395 		case '1':
396 			type = FILE_BYTE;
397 			break;
398 		case '2':
399 			type = FILE_SHORT;
400 			break;
401 		case '4':
402 			type = FILE_LONG;
403 			break;
404 		case '8':
405 			type = FILE_QUAD;
406 			break;
407 		default:
408 			/* XXX - what about 3, 5, 6, or 7? */
409 			return FILE_INVALID;
410 		}
411 		l += 2;
412 	} else {
413 		/*
414 		 * "d" or "u" by itself.
415 		 */
416 		type = FILE_LONG;
417 		++l;
418 	}
419 	if (t)
420 		*t = l;
421 	return type;
422 }
423 
424 file_private void
init_file_tables(void)425 init_file_tables(void)
426 {
427 	static int done = 0;
428 	const struct type_tbl_s *p;
429 
430 	if (done)
431 		return;
432 	done++;
433 
434 	for (p = type_tbl; p->len; p++) {
435 		assert(p->type < FILE_NAMES_SIZE);
436 		file_names[p->type] = p->name;
437 		file_formats[p->type] = p->format;
438 	}
439 	assert(p - type_tbl == FILE_NAMES_SIZE);
440 }
441 
442 file_private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)443 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
444 {
445 	struct mlist *ml;
446 
447 	mlp->map = NULL;
448 	if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
449 		return -1;
450 
451 	ml->map = idx == 0 ? map : NULL;
452 	ml->magic = map->magic[idx];
453 	ml->nmagic = map->nmagic[idx];
454 	if (ml->nmagic) {
455 		ml->magic_rxcomp = CAST(file_regex_t **,
456 		    calloc(ml->nmagic, sizeof(*ml->magic_rxcomp)));
457 		if (ml->magic_rxcomp == NULL) {
458 			free(ml);
459 			return -1;
460 		}
461 	} else
462 		ml->magic_rxcomp = NULL;
463 	mlp->prev->next = ml;
464 	ml->prev = mlp->prev;
465 	ml->next = mlp;
466 	mlp->prev = ml;
467 	return 0;
468 }
469 
470 /*
471  * Handle one file or directory.
472  */
473 file_private int
apprentice_1(struct magic_set * ms,const char * fn,int action)474 apprentice_1(struct magic_set *ms, const char *fn, int action)
475 {
476 	struct magic_map *map;
477 #ifndef COMPILE_ONLY
478 	size_t i;
479 #endif
480 
481 	if (magicsize != FILE_MAGICSIZE) {
482 		file_error(ms, 0, "magic element size %lu != %lu",
483 		    CAST(unsigned long, sizeof(*map->magic[0])),
484 		    CAST(unsigned long, FILE_MAGICSIZE));
485 		return -1;
486 	}
487 
488 	if (action == FILE_COMPILE) {
489 		map = apprentice_load(ms, fn, action);
490 		if (map == NULL)
491 			return -1;
492 		return apprentice_compile(ms, map, fn);
493 	}
494 
495 #ifndef COMPILE_ONLY
496 	map = apprentice_map(ms, fn);
497 	if (map == NULL) {
498 		if (ms->flags & MAGIC_CHECK)
499 			file_magwarn(NULL, "using regular magic file `%s'", fn);
500 		map = apprentice_load(ms, fn, action);
501 		if (map == NULL)
502 			return -1;
503 	}
504 
505 	for (i = 0; i < MAGIC_SETS; i++) {
506 		if (add_mlist(ms->mlist[i], map, i) == -1) {
507 			/* failed to add to any list, free explicitly */
508 			if (i == 0)
509 				apprentice_unmap(map);
510 			else
511 				mlist_free_all(ms);
512 			file_oomem(ms, sizeof(*ms->mlist[0]));
513 			return -1;
514 		}
515 	}
516 
517 	if (action == FILE_LIST) {
518 		for (i = 0; i < MAGIC_SETS; i++) {
519 			printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
520 			    i);
521 			apprentice_list(ms->mlist[i], BINTEST);
522 			printf("Text patterns:\n");
523 			apprentice_list(ms->mlist[i], TEXTTEST);
524 		}
525 	}
526 	return 0;
527 #else
528 	return 0;
529 #endif /* COMPILE_ONLY */
530 }
531 
532 file_protected void
file_ms_free(struct magic_set * ms)533 file_ms_free(struct magic_set *ms)
534 {
535 	size_t i;
536 	if (ms == NULL)
537 		return;
538 	for (i = 0; i < MAGIC_SETS; i++)
539 		mlist_free(ms->mlist[i]);
540 	free(ms->o.pbuf);
541 	free(ms->o.buf);
542 	free(ms->c.li);
543 #ifdef USE_C_LOCALE
544 	freelocale(ms->c_lc_ctype);
545 #endif
546 	free(ms);
547 }
548 
549 file_protected struct magic_set *
file_ms_alloc(int flags)550 file_ms_alloc(int flags)
551 {
552 	struct magic_set *ms;
553 	size_t i, len;
554 
555 	if ((ms = CAST(struct magic_set *, calloc(CAST(size_t, 1u),
556 	    sizeof(*ms)))) == NULL)
557 		return NULL;
558 
559 	if (magic_setflags(ms, flags) == -1) {
560 		errno = EINVAL;
561 		goto free;
562 	}
563 
564 	ms->o.buf = ms->o.pbuf = NULL;
565 	ms->o.blen = 0;
566 	len = (ms->c.len = 10) * sizeof(*ms->c.li);
567 
568 	if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
569 		goto free;
570 
571 	ms->event_flags = 0;
572 	ms->error = -1;
573 	for (i = 0; i < MAGIC_SETS; i++)
574 		ms->mlist[i] = NULL;
575 	ms->file = "unknown";
576 	ms->line = 0;
577 	ms->indir_max = FILE_INDIR_MAX;
578 	ms->name_max = FILE_NAME_MAX;
579 	ms->elf_shnum_max = FILE_ELF_SHNUM_MAX;
580 	ms->elf_shsize_max = FILE_ELF_SHSIZE_MAX;
581 	ms->elf_phnum_max = FILE_ELF_PHNUM_MAX;
582 	ms->elf_notes_max = FILE_ELF_NOTES_MAX;
583 	ms->regex_max = FILE_REGEX_MAX;
584 	ms->bytes_max = FILE_BYTES_MAX;
585 	ms->encoding_max = FILE_ENCODING_MAX;
586 #ifdef USE_C_LOCALE
587 	ms->c_lc_ctype = newlocale(LC_CTYPE_MASK, "C", 0);
588 	assert(ms->c_lc_ctype != NULL);
589 #endif
590 	return ms;
591 free:
592 	free(ms);
593 	return NULL;
594 }
595 
596 file_private void
apprentice_unmap(struct magic_map * map)597 apprentice_unmap(struct magic_map *map)
598 {
599 	size_t i;
600 	char *p;
601 	if (map == NULL)
602 		return;
603 
604 	switch (map->type) {
605 	case MAP_TYPE_USER:
606 		break;
607 	case MAP_TYPE_MALLOC:
608 		p = CAST(char *, map->p);
609 		for (i = 0; i < MAGIC_SETS; i++) {
610 			char *b = RCAST(char *, map->magic[i]);
611 			if (p != NULL && b >= p && b <= p + map->len)
612 				continue;
613 			free(b);
614 		}
615 		free(p);
616 		break;
617 #ifdef QUICK
618 	case MAP_TYPE_MMAP:
619 		if (map->p && map->p != MAP_FAILED)
620 			(void)munmap(map->p, map->len);
621 		break;
622 #endif
623 	default:
624 		fprintf(stderr, "Bad map type %d", map->type);
625 		abort();
626 	}
627 	free(map);
628 }
629 
630 file_private struct mlist *
mlist_alloc(void)631 mlist_alloc(void)
632 {
633 	struct mlist *mlist;
634 	if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
635 		return NULL;
636 	}
637 	mlist->next = mlist->prev = mlist;
638 	return mlist;
639 }
640 
641 file_private void
mlist_free_all(struct magic_set * ms)642 mlist_free_all(struct magic_set *ms)
643 {
644 	size_t i;
645 
646 	for (i = 0; i < MAGIC_SETS; i++) {
647 		mlist_free(ms->mlist[i]);
648 		ms->mlist[i] = NULL;
649 	}
650 }
651 
652 file_private void
mlist_free_one(struct mlist * ml)653 mlist_free_one(struct mlist *ml)
654 {
655 	size_t i;
656 
657 	if (ml->map)
658 		apprentice_unmap(CAST(struct magic_map *, ml->map));
659 
660 	for (i = 0; i < ml->nmagic; ++i) {
661 		if (ml->magic_rxcomp[i]) {
662 			file_regfree(ml->magic_rxcomp[i]);
663 			free(ml->magic_rxcomp[i]);
664 			ml->magic_rxcomp[i] = NULL;
665 		}
666 	}
667 	free(ml->magic_rxcomp);
668 	ml->magic_rxcomp = NULL;
669 	free(ml);
670 }
671 
672 file_private void
mlist_free(struct mlist * mlist)673 mlist_free(struct mlist *mlist)
674 {
675 	struct mlist *ml, *next;
676 
677 	if (mlist == NULL)
678 		return;
679 
680 	for (ml = mlist->next; ml != mlist;) {
681 		next = ml->next;
682 		mlist_free_one(ml);
683 		ml = next;
684 	}
685 	mlist_free_one(mlist);
686 }
687 
688 #ifndef COMPILE_ONLY
689 /* void **bufs: an array of compiled magic files */
690 file_protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)691 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
692     size_t *sizes, size_t nbufs)
693 {
694 	size_t i, j;
695 	struct magic_map *map;
696 
697 	if (nbufs == 0)
698 		return -1;
699 
700 	(void)file_reset(ms, 0);
701 
702 	init_file_tables();
703 
704 	for (i = 0; i < MAGIC_SETS; i++) {
705 		mlist_free(ms->mlist[i]);
706 		if ((ms->mlist[i] = mlist_alloc()) == NULL) {
707 			file_oomem(ms, sizeof(*ms->mlist[0]));
708 			goto fail;
709 		}
710 	}
711 
712 	for (i = 0; i < nbufs; i++) {
713 		map = apprentice_buf(ms, bufs[i], sizes[i]);
714 		if (map == NULL)
715 			goto fail;
716 
717 		for (j = 0; j < MAGIC_SETS; j++) {
718 			if (add_mlist(ms->mlist[j], map, j) == -1) {
719 				file_oomem(ms, sizeof(*ms->mlist[0]));
720 				goto fail;
721 			}
722 		}
723 	}
724 
725 	return 0;
726 fail:
727 	mlist_free_all(ms);
728 	return -1;
729 }
730 #endif
731 
732 /* const char *fn: list of magic files and directories */
733 file_protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)734 file_apprentice(struct magic_set *ms, const char *fn, int action)
735 {
736 	char *p, *mfn;
737 	int fileerr, errs = -1;
738 	size_t i, j;
739 
740 	(void)file_reset(ms, 0);
741 
742 	if ((fn = magic_getpath(fn, action)) == NULL)
743 		return -1;
744 
745 	init_file_tables();
746 
747 	if ((mfn = strdup(fn)) == NULL) {
748 		file_oomem(ms, strlen(fn));
749 		return -1;
750 	}
751 
752 	for (i = 0; i < MAGIC_SETS; i++) {
753 		mlist_free(ms->mlist[i]);
754 		if ((ms->mlist[i] = mlist_alloc()) == NULL) {
755 			file_oomem(ms, sizeof(*ms->mlist[0]));
756 			for (j = 0; j < i; j++) {
757 				mlist_free(ms->mlist[j]);
758 				ms->mlist[j] = NULL;
759 			}
760 			free(mfn);
761 			return -1;
762 		}
763 	}
764 	fn = mfn;
765 
766 	while (fn) {
767 		p = CCAST(char *, strchr(fn, PATHSEP));
768 		if (p)
769 			*p++ = '\0';
770 		if (*fn == '\0')
771 			break;
772 		fileerr = apprentice_1(ms, fn, action);
773 		errs = MAX(errs, fileerr);
774 		fn = p;
775 	}
776 
777 	free(mfn);
778 
779 	if (errs == -1) {
780 		for (i = 0; i < MAGIC_SETS; i++) {
781 			mlist_free(ms->mlist[i]);
782 			ms->mlist[i] = NULL;
783 		}
784 		file_error(ms, 0, "could not find any valid magic files!");
785 		return -1;
786 	}
787 
788 #if 0
789 	/*
790 	 * Always leave the database loaded
791 	 */
792 	if (action == FILE_LOAD)
793 		return 0;
794 
795 	for (i = 0; i < MAGIC_SETS; i++) {
796 		mlist_free(ms->mlist[i]);
797 		ms->mlist[i] = NULL;
798 	}
799 #endif
800 
801 	switch (action) {
802 	case FILE_LOAD:
803 	case FILE_COMPILE:
804 	case FILE_CHECK:
805 	case FILE_LIST:
806 		return 0;
807 	default:
808 		file_error(ms, 0, "Invalid action %d", action);
809 		return -1;
810 	}
811 }
812 
813 /*
814  * Compute the real length of a magic expression, for the purposes
815  * of determining how "strong" a magic expression is (approximating
816  * how specific its matches are):
817  *	- magic characters count 0 unless escaped.
818  *	- [] expressions count 1
819  *	- {} expressions count 0
820  *	- regular characters or escaped magic characters count 1
821  *	- 0 length expressions count as one
822  */
823 file_private size_t
nonmagic(const char * str)824 nonmagic(const char *str)
825 {
826 	const char *p;
827 	size_t rv = 0;
828 
829 	for (p = str; *p; p++)
830 		switch (*p) {
831 		case '\\':	/* Escaped anything counts 1 */
832 			if (!*++p)
833 				p--;
834 			rv++;
835 			continue;
836 		case '?':	/* Magic characters count 0 */
837 		case '*':
838 		case '.':
839 		case '+':
840 		case '^':
841 		case '$':
842 			continue;
843 		case '[':	/* Bracketed expressions count 1 the ']' */
844 			while (*p && *p != ']')
845 				p++;
846 			p--;
847 			continue;
848 		case '{':	/* Braced expressions count 0 */
849 			while (*p && *p != '}')
850 				p++;
851 			if (!*p)
852 				p--;
853 			continue;
854 		default:	/* Anything else counts 1 */
855 			rv++;
856 			continue;
857 		}
858 
859 	return rv == 0 ? 1 : rv;	/* Return at least 1 */
860 }
861 
862 
863 file_private size_t
typesize(int type)864 typesize(int type)
865 {
866 	switch (type) {
867 	case FILE_BYTE:
868 		return 1;
869 
870 	case FILE_SHORT:
871 	case FILE_LESHORT:
872 	case FILE_BESHORT:
873 	case FILE_MSDOSDATE:
874 	case FILE_BEMSDOSDATE:
875 	case FILE_LEMSDOSDATE:
876 	case FILE_MSDOSTIME:
877 	case FILE_BEMSDOSTIME:
878 	case FILE_LEMSDOSTIME:
879 		return 2;
880 
881 	case FILE_LONG:
882 	case FILE_LELONG:
883 	case FILE_BELONG:
884 	case FILE_MELONG:
885 		return 4;
886 
887 	case FILE_DATE:
888 	case FILE_LEDATE:
889 	case FILE_BEDATE:
890 	case FILE_MEDATE:
891 	case FILE_LDATE:
892 	case FILE_LELDATE:
893 	case FILE_BELDATE:
894 	case FILE_MELDATE:
895 	case FILE_FLOAT:
896 	case FILE_BEFLOAT:
897 	case FILE_LEFLOAT:
898 	case FILE_BEID3:
899 	case FILE_LEID3:
900 		return 4;
901 
902 	case FILE_QUAD:
903 	case FILE_BEQUAD:
904 	case FILE_LEQUAD:
905 	case FILE_QDATE:
906 	case FILE_LEQDATE:
907 	case FILE_BEQDATE:
908 	case FILE_QLDATE:
909 	case FILE_LEQLDATE:
910 	case FILE_BEQLDATE:
911 	case FILE_QWDATE:
912 	case FILE_LEQWDATE:
913 	case FILE_BEQWDATE:
914 	case FILE_DOUBLE:
915 	case FILE_BEDOUBLE:
916 	case FILE_LEDOUBLE:
917 	case FILE_OFFSET:
918 	case FILE_BEVARINT:
919 	case FILE_LEVARINT:
920 		return 8;
921 
922 	case FILE_GUID:
923 		return 16;
924 
925 	default:
926 		return FILE_BADSIZE;
927 	}
928 }
929 
930 /*
931  * Get weight of this magic entry, for sorting purposes.
932  */
933 file_private ssize_t
apprentice_magic_strength_1(const struct magic * m)934 apprentice_magic_strength_1(const struct magic *m)
935 {
936 #define MULT 10U
937 	size_t ts, v;
938 	ssize_t val = 2 * MULT;	/* baseline strength */
939 
940 	switch (m->type) {
941 	case FILE_DEFAULT:	/* make sure this sorts last */
942 		if (m->factor_op != FILE_FACTOR_OP_NONE) {
943 			file_magwarn(NULL, "Usupported factor_op in default %d",
944 			    m->factor_op);
945 		}
946 		return 0;
947 
948 	case FILE_BYTE:
949 	case FILE_SHORT:
950 	case FILE_LESHORT:
951 	case FILE_BESHORT:
952 	case FILE_LONG:
953 	case FILE_LELONG:
954 	case FILE_BELONG:
955 	case FILE_MELONG:
956 	case FILE_DATE:
957 	case FILE_LEDATE:
958 	case FILE_BEDATE:
959 	case FILE_MEDATE:
960 	case FILE_LDATE:
961 	case FILE_LELDATE:
962 	case FILE_BELDATE:
963 	case FILE_MELDATE:
964 	case FILE_FLOAT:
965 	case FILE_BEFLOAT:
966 	case FILE_LEFLOAT:
967 	case FILE_QUAD:
968 	case FILE_BEQUAD:
969 	case FILE_LEQUAD:
970 	case FILE_QDATE:
971 	case FILE_LEQDATE:
972 	case FILE_BEQDATE:
973 	case FILE_QLDATE:
974 	case FILE_LEQLDATE:
975 	case FILE_BEQLDATE:
976 	case FILE_QWDATE:
977 	case FILE_LEQWDATE:
978 	case FILE_BEQWDATE:
979 	case FILE_DOUBLE:
980 	case FILE_BEDOUBLE:
981 	case FILE_LEDOUBLE:
982 	case FILE_BEVARINT:
983 	case FILE_LEVARINT:
984 	case FILE_GUID:
985 	case FILE_BEID3:
986 	case FILE_LEID3:
987 	case FILE_OFFSET:
988 	case FILE_MSDOSDATE:
989 	case FILE_BEMSDOSDATE:
990 	case FILE_LEMSDOSDATE:
991 	case FILE_MSDOSTIME:
992 	case FILE_BEMSDOSTIME:
993 	case FILE_LEMSDOSTIME:
994 		ts = typesize(m->type);
995 		if (ts == FILE_BADSIZE) {
996 			(void)fprintf(stderr, "Bad size for type %d\n",
997 			    m->type);
998 			abort();
999 		}
1000 		val += ts * MULT;
1001 		break;
1002 
1003 	case FILE_PSTRING:
1004 	case FILE_STRING:
1005 	case FILE_OCTAL:
1006 		val += m->vallen * MULT;
1007 		break;
1008 
1009 	case FILE_BESTRING16:
1010 	case FILE_LESTRING16:
1011 		val += m->vallen * MULT / 2;
1012 		break;
1013 
1014 	case FILE_SEARCH:
1015 		if (m->vallen == 0)
1016 			break;
1017 		val += m->vallen * MAX(MULT / m->vallen, 1);
1018 		break;
1019 
1020 	case FILE_REGEX:
1021 		v = nonmagic(m->value.s);
1022 		val += v * MAX(MULT / v, 1);
1023 		break;
1024 
1025 	case FILE_INDIRECT:
1026 	case FILE_NAME:
1027 	case FILE_USE:
1028 	case FILE_CLEAR:
1029 		break;
1030 
1031 	case FILE_DER:
1032 		val += MULT;
1033 		break;
1034 
1035 	default:
1036 		(void)fprintf(stderr, "Bad type %d\n", m->type);
1037 		abort();
1038 	}
1039 
1040 	switch (m->reln) {
1041 	case 'x':	/* matches anything penalize */
1042 	case '!':       /* matches almost anything penalize */
1043 		val = 0;
1044 		break;
1045 
1046 	case '=':	/* Exact match, prefer */
1047 		val += MULT;
1048 		break;
1049 
1050 	case '>':
1051 	case '<':	/* comparison match reduce strength */
1052 		val -= 2 * MULT;
1053 		break;
1054 
1055 	case '^':
1056 	case '&':	/* masking bits, we could count them too */
1057 		val -= MULT;
1058 		break;
1059 
1060 	default:
1061 		(void)fprintf(stderr, "Bad relation %c\n", m->reln);
1062 		abort();
1063 	}
1064 
1065 	return val;
1066 }
1067 
1068 
1069 /*ARGSUSED*/
1070 file_protected size_t
file_magic_strength(const struct magic * m,size_t nmagic)1071 file_magic_strength(const struct magic *m,
1072     size_t nmagic __attribute__((__unused__)))
1073 {
1074 	ssize_t val = apprentice_magic_strength_1(m);
1075 
1076 #ifdef notyet
1077 	if (m->desc[0] == '\0') {
1078 		size_t i;
1079 		/*
1080 		 * Magic entries with no description get their continuations
1081 		 * added
1082 		 */
1083 		for (i = 1; m[i].cont_level != 0 && i < MIN(nmagic, 3); i++) {
1084 			ssize_t v = apprentice_magic_strength_1(&m[i]) >>
1085 			    (i + 1);
1086 			val += v;
1087 			if (m[i].desc[0] != '\0')
1088 				break;
1089 		}
1090 	}
1091 #endif
1092 
1093 	switch (m->factor_op) {
1094 	case FILE_FACTOR_OP_NONE:
1095 		break;
1096 	case FILE_FACTOR_OP_PLUS:
1097 		val += m->factor;
1098 		break;
1099 	case FILE_FACTOR_OP_MINUS:
1100 		val -= m->factor;
1101 		break;
1102 	case FILE_FACTOR_OP_TIMES:
1103 		val *= m->factor;
1104 		break;
1105 	case FILE_FACTOR_OP_DIV:
1106 		val /= m->factor;
1107 		break;
1108 	default:
1109 		(void)fprintf(stderr, "Bad factor_op %u\n", m->factor_op);
1110 		abort();
1111 	}
1112 
1113 	if (val <= 0)	/* ensure we only return 0 for FILE_DEFAULT */
1114 		val = 1;
1115 
1116 #ifndef notyet
1117 	/*
1118 	 * Magic entries with no description get a bonus because they depend
1119 	 * on subsequent magic entries to print something.
1120 	 */
1121 	if (m->desc[0] == '\0')
1122 		val++;
1123 #endif
1124 
1125 	return val;
1126 }
1127 
1128 /*
1129  * Sort callback for sorting entries by "strength" (basically length)
1130  */
1131 file_private int
apprentice_sort(const void * a,const void * b)1132 apprentice_sort(const void *a, const void *b)
1133 {
1134 	const struct magic_entry *ma = CAST(const struct magic_entry *, a);
1135 	const struct magic_entry *mb = CAST(const struct magic_entry *, b);
1136 	size_t sa = file_magic_strength(ma->mp, ma->cont_count);
1137 	size_t sb = file_magic_strength(mb->mp, mb->cont_count);
1138 	if (sa == sb)
1139 		return 0;
1140 	else if (sa > sb)
1141 		return -1;
1142 	else
1143 		return 1;
1144 }
1145 
1146 /*
1147  * Shows sorted patterns list in the order which is used for the matching
1148  */
1149 file_private void
apprentice_list(struct mlist * mlist,int mode)1150 apprentice_list(struct mlist *mlist, int mode)
1151 {
1152 	uint32_t magindex, descindex, mimeindex, lineindex;
1153 	struct mlist *ml;
1154 	for (ml = mlist->next; ml != mlist; ml = ml->next) {
1155 		for (magindex = 0; magindex < ml->nmagic; magindex++) {
1156 			struct magic *m = &ml->magic[magindex];
1157 			if ((m->flag & mode) != mode) {
1158 				/* Skip sub-tests */
1159 				while (magindex + 1 < ml->nmagic &&
1160 				       ml->magic[magindex + 1].cont_level != 0)
1161 					++magindex;
1162 				continue; /* Skip to next top-level test*/
1163 			}
1164 
1165 			/*
1166 			 * Try to iterate over the tree until we find item with
1167 			 * description/mimetype.
1168 			 */
1169 			lineindex = descindex = mimeindex = magindex;
1170 			for (; magindex + 1 < ml->nmagic &&
1171 			   ml->magic[magindex + 1].cont_level != 0;
1172 			   magindex++) {
1173 				uint32_t mi = magindex + 1;
1174 				if (*ml->magic[descindex].desc == '\0'
1175 				    && *ml->magic[mi].desc)
1176 					descindex = mi;
1177 				if (*ml->magic[mimeindex].mimetype == '\0'
1178 				    && *ml->magic[mi].mimetype)
1179 					mimeindex = mi;
1180 			}
1181 
1182 			printf("Strength = %3" SIZE_T_FORMAT "u@%u: %s [%s]\n",
1183 			    file_magic_strength(m, ml->nmagic - magindex),
1184 			    ml->magic[lineindex].lineno,
1185 			    ml->magic[descindex].desc,
1186 			    ml->magic[mimeindex].mimetype);
1187 		}
1188 	}
1189 }
1190 
1191 file_private void
set_test_type(struct magic * mstart,struct magic * m)1192 set_test_type(struct magic *mstart, struct magic *m)
1193 {
1194 	switch (m->type) {
1195 	case FILE_BYTE:
1196 	case FILE_SHORT:
1197 	case FILE_LONG:
1198 	case FILE_DATE:
1199 	case FILE_BESHORT:
1200 	case FILE_BELONG:
1201 	case FILE_BEDATE:
1202 	case FILE_LESHORT:
1203 	case FILE_LELONG:
1204 	case FILE_LEDATE:
1205 	case FILE_LDATE:
1206 	case FILE_BELDATE:
1207 	case FILE_LELDATE:
1208 	case FILE_MEDATE:
1209 	case FILE_MELDATE:
1210 	case FILE_MELONG:
1211 	case FILE_QUAD:
1212 	case FILE_LEQUAD:
1213 	case FILE_BEQUAD:
1214 	case FILE_QDATE:
1215 	case FILE_LEQDATE:
1216 	case FILE_BEQDATE:
1217 	case FILE_QLDATE:
1218 	case FILE_LEQLDATE:
1219 	case FILE_BEQLDATE:
1220 	case FILE_QWDATE:
1221 	case FILE_LEQWDATE:
1222 	case FILE_BEQWDATE:
1223 	case FILE_FLOAT:
1224 	case FILE_BEFLOAT:
1225 	case FILE_LEFLOAT:
1226 	case FILE_DOUBLE:
1227 	case FILE_BEDOUBLE:
1228 	case FILE_LEDOUBLE:
1229 	case FILE_BEVARINT:
1230 	case FILE_LEVARINT:
1231 	case FILE_DER:
1232 	case FILE_GUID:
1233 	case FILE_OFFSET:
1234 	case FILE_MSDOSDATE:
1235 	case FILE_BEMSDOSDATE:
1236 	case FILE_LEMSDOSDATE:
1237 	case FILE_MSDOSTIME:
1238 	case FILE_BEMSDOSTIME:
1239 	case FILE_LEMSDOSTIME:
1240 	case FILE_OCTAL:
1241 		mstart->flag |= BINTEST;
1242 		break;
1243 	case FILE_STRING:
1244 	case FILE_PSTRING:
1245 	case FILE_BESTRING16:
1246 	case FILE_LESTRING16:
1247 		/* Allow text overrides */
1248 		if (mstart->str_flags & STRING_TEXTTEST)
1249 			mstart->flag |= TEXTTEST;
1250 		else
1251 			mstart->flag |= BINTEST;
1252 		break;
1253 	case FILE_REGEX:
1254 	case FILE_SEARCH:
1255 		/* Check for override */
1256 		if (mstart->str_flags & STRING_BINTEST)
1257 			mstart->flag |= BINTEST;
1258 		if (mstart->str_flags & STRING_TEXTTEST)
1259 			mstart->flag |= TEXTTEST;
1260 
1261 		if (mstart->flag & (TEXTTEST|BINTEST))
1262 			break;
1263 
1264 		/* binary test if pattern is not text */
1265 		if (file_looks_utf8(m->value.us, CAST(size_t, m->vallen), NULL,
1266 		    NULL) <= 0)
1267 			mstart->flag |= BINTEST;
1268 		else
1269 			mstart->flag |= TEXTTEST;
1270 		break;
1271 	case FILE_DEFAULT:
1272 		/* can't deduce anything; we shouldn't see this at the
1273 		   top level anyway */
1274 		break;
1275 	case FILE_INVALID:
1276 	default:
1277 		/* invalid search type, but no need to complain here */
1278 		break;
1279 	}
1280 }
1281 
1282 file_private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1283 addentry(struct magic_set *ms, struct magic_entry *me,
1284    struct magic_entry_set *mset)
1285 {
1286 	size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1287 	if (mset[i].me == NULL || mset[i].count == mset[i].max) {
1288 		struct magic_entry *mp;
1289 
1290 		size_t incr = mset[i].max + ALLOC_INCR;
1291 		if ((mp = CAST(struct magic_entry *,
1292 		    realloc(mset[i].me, sizeof(*mp) * incr))) ==
1293 		    NULL) {
1294 			file_oomem(ms, sizeof(*mp) * incr);
1295 			return -1;
1296 		}
1297 		(void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1298 		    ALLOC_INCR);
1299 		mset[i].me = mp;
1300 		mset[i].max = CAST(uint32_t, incr);
1301 		assert(mset[i].max == incr);
1302 	}
1303 	mset[i].me[mset[i].count++] = *me;
1304 	memset(me, 0, sizeof(*me));
1305 	return 0;
1306 }
1307 
1308 /*
1309  * Load and parse one file.
1310  */
1311 file_private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1312 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1313    struct magic_entry_set *mset)
1314 {
1315 	size_t lineno = 0, llen = 0;
1316 	char *line = NULL;
1317 	ssize_t len;
1318 	struct magic_entry me;
1319 
1320 	FILE *f = fopen(ms->file = fn, "r");
1321 	if (f == NULL) {
1322 		if (errno != ENOENT)
1323 			file_error(ms, errno, "cannot read magic file `%s'",
1324 				   fn);
1325 		(*errs)++;
1326 		return;
1327 	}
1328 
1329 	memset(&me, 0, sizeof(me));
1330 	/* read and parse this file */
1331 	for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1332 	    ms->line++) {
1333 		if (len == 0) /* null line, garbage, etc */
1334 			continue;
1335 		if (line[len - 1] == '\n') {
1336 			lineno++;
1337 			line[len - 1] = '\0'; /* delete newline */
1338 		}
1339 		switch (line[0]) {
1340 		case '\0':	/* empty, do not parse */
1341 		case '#':	/* comment, do not parse */
1342 			continue;
1343 		case '!':
1344 			if (line[1] == ':') {
1345 				size_t i;
1346 
1347 				for (i = 0; bang[i].name != NULL; i++) {
1348 					if (CAST(size_t, len - 2) > bang[i].len &&
1349 					    memcmp(bang[i].name, line + 2,
1350 					    bang[i].len) == 0)
1351 						break;
1352 				}
1353 				if (bang[i].name == NULL) {
1354 					file_error(ms, 0,
1355 					    "Unknown !: entry `%s'", line);
1356 					(*errs)++;
1357 					continue;
1358 				}
1359 				if (me.mp == NULL) {
1360 					file_error(ms, 0,
1361 					    "No current entry for :!%s type",
1362 						bang[i].name);
1363 					(*errs)++;
1364 					continue;
1365 				}
1366 				if ((*bang[i].fun)(ms, &me,
1367 				    line + bang[i].len + 2,
1368 				    len - bang[i].len - 2) != 0) {
1369 					(*errs)++;
1370 					continue;
1371 				}
1372 				continue;
1373 			}
1374 			/*FALLTHROUGH*/
1375 		default:
1376 		again:
1377 			switch (parse(ms, &me, line, lineno, action)) {
1378 			case 0:
1379 				continue;
1380 			case 1:
1381 				(void)addentry(ms, &me, mset);
1382 				goto again;
1383 			default:
1384 				(*errs)++;
1385 				break;
1386 			}
1387 		}
1388 	}
1389 	if (me.mp)
1390 		(void)addentry(ms, &me, mset);
1391 	free(line);
1392 	(void)fclose(f);
1393 }
1394 
1395 /*
1396  * parse a file or directory of files
1397  * const char *fn: name of magic file or directory
1398  */
1399 file_private int
cmpstrp(const void * p1,const void * p2)1400 cmpstrp(const void *p1, const void *p2)
1401 {
1402         return strcmp(*RCAST(char *const *, p1), *RCAST(char *const *, p2));
1403 }
1404 
1405 
1406 file_private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1407 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1408     uint32_t starttest)
1409 {
1410 	static const char text[] = "text";
1411 	static const char binary[] = "binary";
1412 	static const size_t len = sizeof(text);
1413 
1414 	uint32_t i = starttest;
1415 
1416 	do {
1417 		set_test_type(me[starttest].mp, me[i].mp);
1418 		if ((ms->flags & MAGIC_DEBUG) == 0)
1419 			continue;
1420 		(void)fprintf(stderr, "%s%s%s: %s\n",
1421 		    me[i].mp->mimetype,
1422 		    me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1423 		    me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1424 		    me[i].mp->flag & BINTEST ? binary : text);
1425 		if (me[i].mp->flag & BINTEST) {
1426 			char *p = strstr(me[i].mp->desc, text);
1427 			if (p && (p == me[i].mp->desc ||
1428 			    isspace(CAST(unsigned char, p[-1]))) &&
1429 			    (p + len - me[i].mp->desc == MAXstring
1430 			    || (p[len] == '\0' ||
1431 			    isspace(CAST(unsigned char, p[len])))))
1432 				(void)fprintf(stderr, "*** Possible "
1433 				    "binary test for text type\n");
1434 		}
1435 	} while (++i < nme && me[i].mp->cont_level != 0);
1436 	return i;
1437 }
1438 
1439 file_private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1440 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1441 {
1442 	uint32_t i;
1443 	for (i = 0; i < nme; i++) {
1444 		if (me[i].mp->cont_level == 0 &&
1445 		    me[i].mp->type == FILE_DEFAULT) {
1446 			while (++i < nme)
1447 				if (me[i].mp->cont_level == 0)
1448 					break;
1449 			if (i != nme) {
1450 				/* XXX - Ugh! */
1451 				ms->line = me[i].mp->lineno;
1452 				file_magwarn(ms,
1453 				    "level 0 \"default\" did not sort last");
1454 			}
1455 			return;
1456 		}
1457 	}
1458 }
1459 
1460 file_private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1461 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1462     struct magic **ma, uint32_t *nma)
1463 {
1464 	uint32_t i, mentrycount = 0;
1465 	size_t slen;
1466 
1467 	for (i = 0; i < nme; i++)
1468 		mentrycount += me[i].cont_count;
1469 
1470 	if (mentrycount == 0) {
1471 		*ma = NULL;
1472 		*nma = 0;
1473 		return 0;
1474 	}
1475 
1476 	slen = sizeof(**ma) * mentrycount;
1477 	if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1478 		file_oomem(ms, slen);
1479 		return -1;
1480 	}
1481 
1482 	mentrycount = 0;
1483 	for (i = 0; i < nme; i++) {
1484 		(void)memcpy(*ma + mentrycount, me[i].mp,
1485 		    me[i].cont_count * sizeof(**ma));
1486 		mentrycount += me[i].cont_count;
1487 	}
1488 	*nma = mentrycount;
1489 	return 0;
1490 }
1491 
1492 file_private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1493 magic_entry_free(struct magic_entry *me, uint32_t nme)
1494 {
1495 	uint32_t i;
1496 	if (me == NULL)
1497 		return;
1498 	for (i = 0; i < nme; i++)
1499 		free(me[i].mp);
1500 	free(me);
1501 }
1502 
1503 file_private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1504 apprentice_load(struct magic_set *ms, const char *fn, int action)
1505 {
1506 	int errs = 0;
1507 	uint32_t i, j;
1508 	size_t files = 0, maxfiles = 0;
1509 	char **filearr = NULL, *mfn;
1510 	struct stat st;
1511 	struct magic_map *map;
1512 	struct magic_entry_set mset[MAGIC_SETS];
1513 	DIR *dir;
1514 	struct dirent *d;
1515 
1516 	memset(mset, 0, sizeof(mset));
1517 	ms->flags |= MAGIC_CHECK;	/* Enable checks for parsed files */
1518 
1519 
1520 	if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1521 	{
1522 		file_oomem(ms, sizeof(*map));
1523 		return NULL;
1524 	}
1525 	map->type = MAP_TYPE_MALLOC;
1526 
1527 	/* print silly verbose header for USG compat. */
1528 	if (action == FILE_CHECK)
1529 		(void)fprintf(stderr, "%s\n", usg_hdr);
1530 
1531 	/* load directory or file */
1532 	if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1533 		dir = opendir(fn);
1534 		if (!dir) {
1535 			errs++;
1536 			goto out;
1537 		}
1538 		while ((d = readdir(dir)) != NULL) {
1539 			if (d->d_name[0] == '.')
1540 				continue;
1541 			if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1542 				file_oomem(ms,
1543 				    strlen(fn) + strlen(d->d_name) + 2);
1544 				errs++;
1545 				closedir(dir);
1546 				goto out;
1547 			}
1548 			if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1549 				free(mfn);
1550 				continue;
1551 			}
1552 			if (files >= maxfiles) {
1553 				size_t mlen;
1554 				char **nfilearr;
1555 				maxfiles = (maxfiles + 1) * 2;
1556 				mlen = maxfiles * sizeof(*filearr);
1557 				if ((nfilearr = CAST(char **,
1558 				    realloc(filearr, mlen))) == NULL) {
1559 					file_oomem(ms, mlen);
1560 					free(mfn);
1561 					closedir(dir);
1562 					errs++;
1563 					goto out;
1564 				}
1565 				filearr = nfilearr;
1566 			}
1567 			filearr[files++] = mfn;
1568 		}
1569 		closedir(dir);
1570 		if (filearr) {
1571 			qsort(filearr, files, sizeof(*filearr), cmpstrp);
1572 			for (i = 0; i < files; i++) {
1573 				load_1(ms, action, filearr[i], &errs, mset);
1574 				free(filearr[i]);
1575 			}
1576 			free(filearr);
1577 			filearr = NULL;
1578 		}
1579 	} else
1580 		load_1(ms, action, fn, &errs, mset);
1581 	if (errs)
1582 		goto out;
1583 
1584 	for (j = 0; j < MAGIC_SETS; j++) {
1585 		/* Set types of tests */
1586 		for (i = 0; i < mset[j].count; ) {
1587 			if (mset[j].me[i].mp->cont_level != 0) {
1588 				i++;
1589 				continue;
1590 			}
1591 			i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1592 		}
1593 		if (mset[j].me)
1594 			qsort(mset[j].me, mset[j].count, sizeof(*mset[0].me),
1595 			    apprentice_sort);
1596 
1597 		/*
1598 		 * Make sure that any level 0 "default" line is last
1599 		 * (if one exists).
1600 		 */
1601 		set_last_default(ms, mset[j].me, mset[j].count);
1602 
1603 		/* coalesce per file arrays into a single one, if needed */
1604 		if (mset[j].count == 0)
1605 			continue;
1606 
1607 		if (coalesce_entries(ms, mset[j].me, mset[j].count,
1608 		    &map->magic[j], &map->nmagic[j]) == -1) {
1609 			errs++;
1610 			goto out;
1611 		}
1612 	}
1613 
1614 out:
1615 	free(filearr);
1616 	for (j = 0; j < MAGIC_SETS; j++)
1617 		magic_entry_free(mset[j].me, mset[j].count);
1618 
1619 	if (errs) {
1620 		apprentice_unmap(map);
1621 		return NULL;
1622 	}
1623 	return map;
1624 }
1625 
1626 /*
1627  * extend the sign bit if the comparison is to be signed
1628  */
1629 file_protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1630 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1631 {
1632 	if (!(m->flag & UNSIGNED)) {
1633 		switch(m->type) {
1634 		/*
1635 		 * Do not remove the casts below.  They are
1636 		 * vital.  When later compared with the data,
1637 		 * the sign extension must have happened.
1638 		 */
1639 		case FILE_BYTE:
1640 			v = CAST(signed char,  v);
1641 			break;
1642 		case FILE_SHORT:
1643 		case FILE_BESHORT:
1644 		case FILE_LESHORT:
1645 			v = CAST(short, v);
1646 			break;
1647 		case FILE_DATE:
1648 		case FILE_BEDATE:
1649 		case FILE_LEDATE:
1650 		case FILE_MEDATE:
1651 		case FILE_LDATE:
1652 		case FILE_BELDATE:
1653 		case FILE_LELDATE:
1654 		case FILE_MELDATE:
1655 		case FILE_LONG:
1656 		case FILE_BELONG:
1657 		case FILE_LELONG:
1658 		case FILE_MELONG:
1659 		case FILE_FLOAT:
1660 		case FILE_BEFLOAT:
1661 		case FILE_LEFLOAT:
1662 		case FILE_MSDOSDATE:
1663 		case FILE_BEMSDOSDATE:
1664 		case FILE_LEMSDOSDATE:
1665 		case FILE_MSDOSTIME:
1666 		case FILE_BEMSDOSTIME:
1667 		case FILE_LEMSDOSTIME:
1668 			v = CAST(int32_t, v);
1669 			break;
1670 		case FILE_QUAD:
1671 		case FILE_BEQUAD:
1672 		case FILE_LEQUAD:
1673 		case FILE_QDATE:
1674 		case FILE_QLDATE:
1675 		case FILE_QWDATE:
1676 		case FILE_BEQDATE:
1677 		case FILE_BEQLDATE:
1678 		case FILE_BEQWDATE:
1679 		case FILE_LEQDATE:
1680 		case FILE_LEQLDATE:
1681 		case FILE_LEQWDATE:
1682 		case FILE_DOUBLE:
1683 		case FILE_BEDOUBLE:
1684 		case FILE_LEDOUBLE:
1685 		case FILE_OFFSET:
1686 		case FILE_BEVARINT:
1687 		case FILE_LEVARINT:
1688 			v = CAST(int64_t, v);
1689 			break;
1690 		case FILE_STRING:
1691 		case FILE_PSTRING:
1692 		case FILE_BESTRING16:
1693 		case FILE_LESTRING16:
1694 		case FILE_REGEX:
1695 		case FILE_SEARCH:
1696 		case FILE_DEFAULT:
1697 		case FILE_INDIRECT:
1698 		case FILE_NAME:
1699 		case FILE_USE:
1700 		case FILE_CLEAR:
1701 		case FILE_DER:
1702 		case FILE_GUID:
1703 		case FILE_OCTAL:
1704 			break;
1705 		default:
1706 			if (ms->flags & MAGIC_CHECK)
1707 			    file_magwarn(ms, "cannot happen: m->type=%d\n",
1708 				    m->type);
1709 			return FILE_BADSIZE;
1710 		}
1711 	}
1712 	return v;
1713 }
1714 
1715 file_private int
string_modifier_check(struct magic_set * ms,struct magic * m)1716 string_modifier_check(struct magic_set *ms, struct magic *m)
1717 {
1718 	if ((ms->flags & MAGIC_CHECK) == 0)
1719 		return 0;
1720 
1721 	if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1722 	    (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1723 		file_magwarn(ms,
1724 		    "'/BHhLl' modifiers are only allowed for pascal strings\n");
1725 		return -1;
1726 	}
1727 	switch (m->type) {
1728 	case FILE_BESTRING16:
1729 	case FILE_LESTRING16:
1730 		if (m->str_flags != 0) {
1731 			file_magwarn(ms,
1732 			    "no modifiers allowed for 16-bit strings\n");
1733 			return -1;
1734 		}
1735 		break;
1736 	case FILE_STRING:
1737 	case FILE_PSTRING:
1738 		if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1739 			file_magwarn(ms,
1740 			    "'/%c' only allowed on regex and search\n",
1741 			    CHAR_REGEX_OFFSET_START);
1742 			return -1;
1743 		}
1744 		break;
1745 	case FILE_SEARCH:
1746 		if (m->str_range == 0) {
1747 			file_magwarn(ms,
1748 			    "missing range; defaulting to %d\n",
1749                             STRING_DEFAULT_RANGE);
1750 			m->str_range = STRING_DEFAULT_RANGE;
1751 			return -1;
1752 		}
1753 		break;
1754 	case FILE_REGEX:
1755 		if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1756 			file_magwarn(ms, "'/%c' not allowed on regex\n",
1757 			    CHAR_COMPACT_WHITESPACE);
1758 			return -1;
1759 		}
1760 		if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1761 			file_magwarn(ms, "'/%c' not allowed on regex\n",
1762 			    CHAR_COMPACT_OPTIONAL_WHITESPACE);
1763 			return -1;
1764 		}
1765 		break;
1766 	default:
1767 		file_magwarn(ms, "coding error: m->type=%d\n",
1768 		    m->type);
1769 		return -1;
1770 	}
1771 	return 0;
1772 }
1773 
1774 file_private int
get_op(char c)1775 get_op(char c)
1776 {
1777 	switch (c) {
1778 	case '&':
1779 		return FILE_OPAND;
1780 	case '|':
1781 		return FILE_OPOR;
1782 	case '^':
1783 		return FILE_OPXOR;
1784 	case '+':
1785 		return FILE_OPADD;
1786 	case '-':
1787 		return FILE_OPMINUS;
1788 	case '*':
1789 		return FILE_OPMULTIPLY;
1790 	case '/':
1791 		return FILE_OPDIVIDE;
1792 	case '%':
1793 		return FILE_OPMODULO;
1794 	default:
1795 		return -1;
1796 	}
1797 }
1798 
1799 #ifdef ENABLE_CONDITIONALS
1800 file_private int
get_cond(const char * l,const char ** t)1801 get_cond(const char *l, const char **t)
1802 {
1803 	static const struct cond_tbl_s {
1804 		char name[8];
1805 		size_t len;
1806 		int cond;
1807 	} cond_tbl[] = {
1808 		{ "if",		2,	COND_IF },
1809 		{ "elif",	4,	COND_ELIF },
1810 		{ "else",	4,	COND_ELSE },
1811 		{ "",		0,	COND_NONE },
1812 	};
1813 	const struct cond_tbl_s *p;
1814 
1815 	for (p = cond_tbl; p->len; p++) {
1816 		if (strncmp(l, p->name, p->len) == 0 &&
1817 		    isspace(CAST(unsigned char, l[p->len]))) {
1818 			if (t)
1819 				*t = l + p->len;
1820 			break;
1821 		}
1822 	}
1823 	return p->cond;
1824 }
1825 
1826 file_private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1827 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1828 {
1829 	int last_cond;
1830 	last_cond = ms->c.li[cont_level].last_cond;
1831 
1832 	switch (cond) {
1833 	case COND_IF:
1834 		if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1835 			if (ms->flags & MAGIC_CHECK)
1836 				file_magwarn(ms, "syntax error: `if'");
1837 			return -1;
1838 		}
1839 		last_cond = COND_IF;
1840 		break;
1841 
1842 	case COND_ELIF:
1843 		if (last_cond != COND_IF && last_cond != COND_ELIF) {
1844 			if (ms->flags & MAGIC_CHECK)
1845 				file_magwarn(ms, "syntax error: `elif'");
1846 			return -1;
1847 		}
1848 		last_cond = COND_ELIF;
1849 		break;
1850 
1851 	case COND_ELSE:
1852 		if (last_cond != COND_IF && last_cond != COND_ELIF) {
1853 			if (ms->flags & MAGIC_CHECK)
1854 				file_magwarn(ms, "syntax error: `else'");
1855 			return -1;
1856 		}
1857 		last_cond = COND_NONE;
1858 		break;
1859 
1860 	case COND_NONE:
1861 		last_cond = COND_NONE;
1862 		break;
1863 	}
1864 
1865 	ms->c.li[cont_level].last_cond = last_cond;
1866 	return 0;
1867 }
1868 #endif /* ENABLE_CONDITIONALS */
1869 
1870 file_private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1871 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1872 {
1873 	const char *l = *lp;
1874 
1875 	while (!isspace(CAST(unsigned char, *++l)))
1876 		switch (*l) {
1877 		case CHAR_INDIRECT_RELATIVE:
1878 			m->str_flags |= INDIRECT_RELATIVE;
1879 			break;
1880 		default:
1881 			if (ms->flags & MAGIC_CHECK)
1882 				file_magwarn(ms, "indirect modifier `%c' "
1883 					"invalid", *l);
1884 			*lp = l;
1885 			return -1;
1886 		}
1887 	*lp = l;
1888 	return 0;
1889 }
1890 
1891 file_private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1892 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1893     int op)
1894 {
1895 	const char *l = *lp;
1896 	char *t;
1897 	uint64_t val;
1898 
1899 	++l;
1900 	m->mask_op |= op;
1901 	val = CAST(uint64_t, strtoull(l, &t, 0));
1902 	l = t;
1903 	m->num_mask = file_signextend(ms, m, val);
1904 	eatsize(&l);
1905 	*lp = l;
1906 }
1907 
1908 file_private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1909 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1910 {
1911 	const char *l = *lp;
1912 	char *t;
1913 	int have_range = 0;
1914 
1915 	while (!isspace(CAST(unsigned char, *++l))) {
1916 		switch (*l) {
1917 		case '0':  case '1':  case '2':
1918 		case '3':  case '4':  case '5':
1919 		case '6':  case '7':  case '8':
1920 		case '9':
1921 			if (have_range && (ms->flags & MAGIC_CHECK))
1922 				file_magwarn(ms, "multiple ranges");
1923 			have_range = 1;
1924 			m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1925 			if (m->str_range == 0)
1926 				file_magwarn(ms, "zero range");
1927 			l = t - 1;
1928 			break;
1929 		case CHAR_COMPACT_WHITESPACE:
1930 			m->str_flags |= STRING_COMPACT_WHITESPACE;
1931 			break;
1932 		case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1933 			m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1934 			break;
1935 		case CHAR_IGNORE_LOWERCASE:
1936 			m->str_flags |= STRING_IGNORE_LOWERCASE;
1937 			break;
1938 		case CHAR_IGNORE_UPPERCASE:
1939 			m->str_flags |= STRING_IGNORE_UPPERCASE;
1940 			break;
1941 		case CHAR_REGEX_OFFSET_START:
1942 			m->str_flags |= REGEX_OFFSET_START;
1943 			break;
1944 		case CHAR_BINTEST:
1945 			m->str_flags |= STRING_BINTEST;
1946 			break;
1947 		case CHAR_TEXTTEST:
1948 			m->str_flags |= STRING_TEXTTEST;
1949 			break;
1950 		case CHAR_TRIM:
1951 			m->str_flags |= STRING_TRIM;
1952 			break;
1953 		case CHAR_FULL_WORD:
1954 			m->str_flags |= STRING_FULL_WORD;
1955 			break;
1956 		case CHAR_PSTRING_1_LE:
1957 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1958 			if (m->type != FILE_PSTRING)
1959 				goto bad;
1960 			SET_LENGTH(PSTRING_1_LE);
1961 			break;
1962 		case CHAR_PSTRING_2_BE:
1963 			if (m->type != FILE_PSTRING)
1964 				goto bad;
1965 			SET_LENGTH(PSTRING_2_BE);
1966 			break;
1967 		case CHAR_PSTRING_2_LE:
1968 			if (m->type != FILE_PSTRING)
1969 				goto bad;
1970 			SET_LENGTH(PSTRING_2_LE);
1971 			break;
1972 		case CHAR_PSTRING_4_BE:
1973 			if (m->type != FILE_PSTRING)
1974 				goto bad;
1975 			SET_LENGTH(PSTRING_4_BE);
1976 			break;
1977 		case CHAR_PSTRING_4_LE:
1978 			switch (m->type) {
1979 			case FILE_PSTRING:
1980 			case FILE_REGEX:
1981 				break;
1982 			default:
1983 				goto bad;
1984 			}
1985 			SET_LENGTH(PSTRING_4_LE);
1986 			break;
1987 		case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
1988 			if (m->type != FILE_PSTRING)
1989 				goto bad;
1990 			m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
1991 			break;
1992 		default:
1993 		bad:
1994 			if (ms->flags & MAGIC_CHECK)
1995 				file_magwarn(ms, "string modifier `%c' "
1996 					"invalid", *l);
1997 			goto out;
1998 		}
1999 		/* allow multiple '/' for readability */
2000 		if (l[1] == '/' && !isspace(CAST(unsigned char, l[2])))
2001 			l++;
2002 	}
2003 	if (string_modifier_check(ms, m) == -1)
2004 		goto out;
2005 	*lp = l;
2006 	return 0;
2007 out:
2008 	*lp = l;
2009 	return -1;
2010 }
2011 
2012 /*
2013  * parse one line from magic file, put into magic[index++] if valid
2014  */
2015 file_private int
parse(struct magic_set * ms,struct magic_entry * me,const char * line,size_t lineno,int action)2016 parse(struct magic_set *ms, struct magic_entry *me, const char *line,
2017     size_t lineno, int action)
2018 {
2019 #ifdef ENABLE_CONDITIONALS
2020 	static uint32_t last_cont_level = 0;
2021 #endif
2022 	size_t i;
2023 	struct magic *m;
2024 	const char *l = line;
2025 	char *t;
2026 	int op;
2027 	uint32_t cont_level;
2028 	int32_t diff;
2029 
2030 	cont_level = 0;
2031 
2032 	/*
2033 	 * Parse the offset.
2034 	 */
2035 	while (*l == '>') {
2036 		++l;		/* step over */
2037 		cont_level++;
2038 	}
2039 #ifdef ENABLE_CONDITIONALS
2040 	if (cont_level == 0 || cont_level > last_cont_level)
2041 		if (file_check_mem(ms, cont_level) == -1)
2042 			return -1;
2043 	last_cont_level = cont_level;
2044 #endif
2045 	if (cont_level != 0) {
2046 		if (me->mp == NULL) {
2047 			file_magerror(ms, "No current entry for continuation");
2048 			return -1;
2049 		}
2050 		if (me->cont_count == 0) {
2051 			file_magerror(ms, "Continuations present with 0 count");
2052 			return -1;
2053 		}
2054 		m = &me->mp[me->cont_count - 1];
2055 		diff = CAST(int32_t, cont_level) - CAST(int32_t, m->cont_level);
2056 		if (diff > 1)
2057 			file_magwarn(ms, "New continuation level %u is more "
2058 			    "than one larger than current level %u", cont_level,
2059 			    m->cont_level);
2060 		if (me->cont_count == me->max_count) {
2061 			struct magic *nm;
2062 			size_t cnt = me->max_count + ALLOC_CHUNK;
2063 			if ((nm = CAST(struct magic *, realloc(me->mp,
2064 			    sizeof(*nm) * cnt))) == NULL) {
2065 				file_oomem(ms, sizeof(*nm) * cnt);
2066 				return -1;
2067 			}
2068 			me->mp = nm;
2069 			me->max_count = CAST(uint32_t, cnt);
2070 		}
2071 		m = &me->mp[me->cont_count++];
2072 		(void)memset(m, 0, sizeof(*m));
2073 		m->cont_level = cont_level;
2074 	} else {
2075 		static const size_t len = sizeof(*m) * ALLOC_CHUNK;
2076 		if (me->mp != NULL)
2077 			return 1;
2078 		if ((m = CAST(struct magic *, malloc(len))) == NULL) {
2079 			file_oomem(ms, len);
2080 			return -1;
2081 		}
2082 		me->mp = m;
2083 		me->max_count = ALLOC_CHUNK;
2084 		(void)memset(m, 0, sizeof(*m));
2085 		m->factor_op = FILE_FACTOR_OP_NONE;
2086 		m->cont_level = 0;
2087 		me->cont_count = 1;
2088 	}
2089 	m->lineno = CAST(uint32_t, lineno);
2090 
2091 	if (*l == '&') {  /* m->cont_level == 0 checked below. */
2092                 ++l;            /* step over */
2093                 m->flag |= OFFADD;
2094         }
2095 	if (*l == '(') {
2096 		++l;		/* step over */
2097 		m->flag |= INDIR;
2098 		if (m->flag & OFFADD)
2099 			m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
2100 
2101 		if (*l == '&') {  /* m->cont_level == 0 checked below */
2102 			++l;            /* step over */
2103 			m->flag |= OFFADD;
2104 		}
2105 	}
2106 	/* Indirect offsets are not valid at level 0. */
2107 	if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) {
2108 		if (ms->flags & MAGIC_CHECK)
2109 			file_magwarn(ms, "relative offset at level 0");
2110 		return -1;
2111 	}
2112 
2113 	/* get offset, then skip over it */
2114 	if (*l == '-') {
2115 		++l;            /* step over */
2116 		m->flag |= OFFNEGATIVE;
2117 	}
2118 	m->offset = CAST(int32_t, strtol(l, &t, 0));
2119         if (l == t) {
2120 		if (ms->flags & MAGIC_CHECK)
2121 			file_magwarn(ms, "offset `%s' invalid", l);
2122 		return -1;
2123 	}
2124 
2125         l = t;
2126 
2127 	if (m->flag & INDIR) {
2128 		m->in_type = FILE_LONG;
2129 		m->in_offset = 0;
2130 		m->in_op = 0;
2131 		/*
2132 		 * read [.,lbs][+-]nnnnn)
2133 		 */
2134 		if (*l == '.' || *l == ',') {
2135 			if (*l == ',')
2136 				m->in_op |= FILE_OPSIGNED;
2137 			l++;
2138 			switch (*l) {
2139 			case 'l':
2140 				m->in_type = FILE_LELONG;
2141 				break;
2142 			case 'L':
2143 				m->in_type = FILE_BELONG;
2144 				break;
2145 			case 'm':
2146 				m->in_type = FILE_MELONG;
2147 				break;
2148 			case 'h':
2149 			case 's':
2150 				m->in_type = FILE_LESHORT;
2151 				break;
2152 			case 'H':
2153 			case 'S':
2154 				m->in_type = FILE_BESHORT;
2155 				break;
2156 			case 'c':
2157 			case 'b':
2158 			case 'C':
2159 			case 'B':
2160 				m->in_type = FILE_BYTE;
2161 				break;
2162 			case 'e':
2163 			case 'f':
2164 			case 'g':
2165 				m->in_type = FILE_LEDOUBLE;
2166 				break;
2167 			case 'E':
2168 			case 'F':
2169 			case 'G':
2170 				m->in_type = FILE_BEDOUBLE;
2171 				break;
2172 			case 'i':
2173 				m->in_type = FILE_LEID3;
2174 				break;
2175 			case 'I':
2176 				m->in_type = FILE_BEID3;
2177 				break;
2178 			case 'o':
2179 				m->in_type = FILE_OCTAL;
2180 				break;
2181 			case 'q':
2182 				m->in_type = FILE_LEQUAD;
2183 				break;
2184 			case 'Q':
2185 				m->in_type = FILE_BEQUAD;
2186 				break;
2187 			default:
2188 				if (ms->flags & MAGIC_CHECK)
2189 					file_magwarn(ms,
2190 					    "indirect offset type `%c' invalid",
2191 					    *l);
2192 				return -1;
2193 			}
2194 			l++;
2195 		}
2196 
2197 		if (*l == '~') {
2198 			m->in_op |= FILE_OPINVERSE;
2199 			l++;
2200 		}
2201 		if ((op = get_op(*l)) != -1) {
2202 			m->in_op |= op;
2203 			l++;
2204 		}
2205 		if (*l == '(') {
2206 			m->in_op |= FILE_OPINDIRECT;
2207 			l++;
2208 		}
2209 		if (isdigit(CAST(unsigned char, *l)) || *l == '-') {
2210 			m->in_offset = CAST(int32_t, strtol(l, &t, 0));
2211 			if (l == t) {
2212 				if (ms->flags & MAGIC_CHECK)
2213 					file_magwarn(ms,
2214 					    "in_offset `%s' invalid", l);
2215 				return -1;
2216 			}
2217 			l = t;
2218 		}
2219 		if (*l++ != ')' ||
2220 		    ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) {
2221 			if (ms->flags & MAGIC_CHECK)
2222 				file_magwarn(ms,
2223 				    "missing ')' in indirect offset");
2224 			return -1;
2225 		}
2226 	}
2227 	EATAB;
2228 
2229 #ifdef ENABLE_CONDITIONALS
2230 	m->cond = get_cond(l, &l);
2231 	if (check_cond(ms, m->cond, cont_level) == -1)
2232 		return -1;
2233 
2234 	EATAB;
2235 #endif
2236 
2237 	/*
2238 	 * Parse the type.
2239 	 */
2240 	if (*l == 'u') {
2241 		/*
2242 		 * Try it as a keyword type prefixed by "u"; match what
2243 		 * follows the "u".  If that fails, try it as an SUS
2244 		 * integer type.
2245 		 */
2246 		m->type = get_type(type_tbl, l + 1, &l);
2247 		if (m->type == FILE_INVALID) {
2248 			/*
2249 			 * Not a keyword type; parse it as an SUS type,
2250 			 * 'u' possibly followed by a number or C/S/L.
2251 			 */
2252 			m->type = get_standard_integer_type(l, &l);
2253 		}
2254 		/* It's unsigned. */
2255 		if (m->type != FILE_INVALID)
2256 			m->flag |= UNSIGNED;
2257 	} else {
2258 		/*
2259 		 * Try it as a keyword type.  If that fails, try it as
2260 		 * an SUS integer type if it begins with "d" or as an
2261 		 * SUS string type if it begins with "s".  In any case,
2262 		 * it's not unsigned.
2263 		 */
2264 		m->type = get_type(type_tbl, l, &l);
2265 		if (m->type == FILE_INVALID) {
2266 			/*
2267 			 * Not a keyword type; parse it as an SUS type,
2268 			 * either 'd' possibly followed by a number or
2269 			 * C/S/L, or just 's'.
2270 			 */
2271 			if (*l == 'd')
2272 				m->type = get_standard_integer_type(l, &l);
2273 			else if (*l == 's'
2274 			    && !isalpha(CAST(unsigned char, l[1]))) {
2275 				m->type = FILE_STRING;
2276 				++l;
2277 			}
2278 		}
2279 	}
2280 
2281 	if (m->type == FILE_INVALID) {
2282 		/* Not found - try it as a special keyword. */
2283 		m->type = get_type(special_tbl, l, &l);
2284 	}
2285 
2286 	if (m->type == FILE_INVALID) {
2287 		if (ms->flags & MAGIC_CHECK)
2288 			file_magwarn(ms, "type `%s' invalid", l);
2289 		return -1;
2290 	}
2291 
2292 	if (m->type == FILE_NAME && cont_level != 0) {
2293 		if (ms->flags & MAGIC_CHECK)
2294 			file_magwarn(ms, "`name%s' entries can only be "
2295 			    "declared at top level", l);
2296 		return -1;
2297 	}
2298 
2299 	/* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2300 	/* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2301 
2302 	m->mask_op = 0;
2303 	if (*l == '~') {
2304 		if (!IS_STRING(m->type))
2305 			m->mask_op |= FILE_OPINVERSE;
2306 		else if (ms->flags & MAGIC_CHECK)
2307 			file_magwarn(ms, "'~' invalid for string types");
2308 		++l;
2309 	}
2310 	m->str_range = 0;
2311 	m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2312 	if ((op = get_op(*l)) != -1) {
2313 		if (IS_STRING(m->type)) {
2314 			int r;
2315 
2316 			if (op != FILE_OPDIVIDE) {
2317 				if (ms->flags & MAGIC_CHECK)
2318 					file_magwarn(ms,
2319 					    "invalid string/indirect op: "
2320 					    "`%c'", *t);
2321 				return -1;
2322 			}
2323 
2324 			if (m->type == FILE_INDIRECT)
2325 				r = parse_indirect_modifier(ms, m, &l);
2326 			else
2327 				r = parse_string_modifier(ms, m, &l);
2328 			if (r == -1)
2329 				return -1;
2330 		} else
2331 			parse_op_modifier(ms, m, &l, op);
2332 	}
2333 
2334 	/*
2335 	 * We used to set mask to all 1's here, instead let's just not do
2336 	 * anything if mask = 0 (unless you have a better idea)
2337 	 */
2338 	EATAB;
2339 
2340 	switch (*l) {
2341 	case '>':
2342 	case '<':
2343   		m->reln = *l;
2344   		++l;
2345 		if (*l == '=') {
2346 			if (ms->flags & MAGIC_CHECK) {
2347 				file_magwarn(ms, "%c= not supported",
2348 				    m->reln);
2349 				return -1;
2350 			}
2351 		   ++l;
2352 		}
2353 		break;
2354 	/* Old-style anding: "0 byte &0x80 dynamically linked" */
2355 	case '&':
2356 	case '^':
2357 	case '=':
2358   		m->reln = *l;
2359   		++l;
2360 		if (*l == '=') {
2361 		   /* HP compat: ignore &= etc. */
2362 		   ++l;
2363 		}
2364 		break;
2365 	case '!':
2366 		m->reln = *l;
2367 		++l;
2368 		break;
2369 	default:
2370   		m->reln = '=';	/* the default relation */
2371 		if (*l == 'x' && ((isascii(CAST(unsigned char, l[1])) &&
2372 		    isspace(CAST(unsigned char, l[1]))) || !l[1])) {
2373 			m->reln = *l;
2374 			++l;
2375 		}
2376 		break;
2377 	}
2378 	/*
2379 	 * Grab the value part, except for an 'x' reln.
2380 	 */
2381 	if (m->reln != 'x' && getvalue(ms, m, &l, action))
2382 		return -1;
2383 
2384 	/*
2385 	 * TODO finish this macro and start using it!
2386 	 * #define offsetcheck {if (offset > ms->bytes_max -1)
2387 	 *	magwarn("offset too big"); }
2388 	 */
2389 
2390 	/*
2391 	 * Now get last part - the description
2392 	 */
2393 	EATAB;
2394 	if (l[0] == '\b') {
2395 		++l;
2396 		m->flag |= NOSPACE;
2397 	} else if ((l[0] == '\\') && (l[1] == 'b')) {
2398 		++l;
2399 		++l;
2400 		m->flag |= NOSPACE;
2401 	}
2402 	for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); )
2403 		continue;
2404 	if (i == sizeof(m->desc)) {
2405 		m->desc[sizeof(m->desc) - 1] = '\0';
2406 		if (ms->flags & MAGIC_CHECK)
2407 			file_magwarn(ms, "description `%s' truncated", m->desc);
2408 	}
2409 
2410         /*
2411 	 * We only do this check while compiling, or if any of the magic
2412 	 * files were not compiled.
2413          */
2414         if (ms->flags & MAGIC_CHECK) {
2415 		if (check_format(ms, m) == -1)
2416 			return -1;
2417 	}
2418 #ifndef COMPILE_ONLY
2419 	if (action == FILE_CHECK) {
2420 		file_mdump(m);
2421 	}
2422 #endif
2423 	m->mimetype[0] = '\0';		/* initialise MIME type to none */
2424 	return 0;
2425 }
2426 
2427 /*
2428  * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2429  * if valid
2430  */
2431 /*ARGSUSED*/
2432 file_private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2433 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line,
2434     size_t len __attribute__((__unused__)))
2435 {
2436 	const char *l = line;
2437 	char *el;
2438 	unsigned long factor;
2439 	char sbuf[512];
2440 	struct magic *m = &me->mp[0];
2441 
2442 	if (m->factor_op != FILE_FACTOR_OP_NONE) {
2443 		file_magwarn(ms,
2444 		    "Current entry already has a strength type: %c %d",
2445 		    m->factor_op, m->factor);
2446 		return -1;
2447 	}
2448 	if (m->type == FILE_NAME) {
2449 		file_magwarn(ms, "%s: Strength setting is not supported in "
2450 		    "\"name\" magic entries",
2451 		    file_printable(ms, sbuf, sizeof(sbuf), m->value.s,
2452 		    sizeof(m->value.s)));
2453 		return -1;
2454 	}
2455 	EATAB;
2456 	switch (*l) {
2457 	case FILE_FACTOR_OP_NONE:
2458 		break;
2459 	case FILE_FACTOR_OP_PLUS:
2460 	case FILE_FACTOR_OP_MINUS:
2461 	case FILE_FACTOR_OP_TIMES:
2462 	case FILE_FACTOR_OP_DIV:
2463 		m->factor_op = *l++;
2464 		break;
2465 	default:
2466 		file_magwarn(ms, "Unknown factor op `%c'", *l);
2467 		return -1;
2468 	}
2469 	EATAB;
2470 	factor = strtoul(l, &el, 0);
2471 	if (factor > 255) {
2472 		file_magwarn(ms, "Too large factor `%lu'", factor);
2473 		goto out;
2474 	}
2475 	if (*el && !isspace(CAST(unsigned char, *el))) {
2476 		file_magwarn(ms, "Bad factor `%s'", l);
2477 		goto out;
2478 	}
2479 	m->factor = CAST(uint8_t, factor);
2480 	if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2481 		file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2482 		    m->factor_op, m->factor);
2483 		goto out;
2484 	}
2485 	return 0;
2486 out:
2487 	m->factor_op = FILE_FACTOR_OP_NONE;
2488 	m->factor = 0;
2489 	return -1;
2490 }
2491 
2492 file_private int
goodchar(unsigned char x,const char * extra)2493 goodchar(unsigned char x, const char *extra)
2494 {
2495 	return (isascii(x) && isalnum(x)) || strchr(extra, x);
2496 }
2497 
2498 file_private int
parse_extra(struct magic_set * ms,struct magic_entry * me,const char * line,size_t llen,off_t off,size_t len,const char * name,const char * extra,int nt)2499 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2500     size_t llen, off_t off, size_t len, const char *name, const char *extra,
2501     int nt)
2502 {
2503 	size_t i;
2504 	const char *l = line;
2505 	struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2506 	char *buf = CAST(char *, CAST(void *, m)) + off;
2507 
2508 	if (buf[0] != '\0') {
2509 		len = nt ? strlen(buf) : len;
2510 		file_magwarn(ms, "Current entry already has a %s type "
2511 		    "`%.*s', new type `%s'", name, CAST(int, len), buf, l);
2512 		return -1;
2513 	}
2514 
2515 	if (*m->desc == '\0') {
2516 		file_magwarn(ms, "Current entry does not yet have a "
2517 		    "description for adding a %s type", name);
2518 		return -1;
2519 	}
2520 
2521 	EATAB;
2522 	for (i = 0; *l && i < llen && i < len && goodchar(*l, extra);
2523 	    buf[i++] = *l++)
2524 		continue;
2525 
2526 	if (i == len && *l) {
2527 		if (nt)
2528 			buf[len - 1] = '\0';
2529 		if (ms->flags & MAGIC_CHECK)
2530 			file_magwarn(ms, "%s type `%s' truncated %"
2531 			    SIZE_T_FORMAT "u", name, line, i);
2532 	} else {
2533 		if (!isspace(CAST(unsigned char, *l)) && !goodchar(*l, extra))
2534 			file_magwarn(ms, "%s type `%s' has bad char '%c'",
2535 			    name, line, *l);
2536 		if (nt)
2537 			buf[i] = '\0';
2538 	}
2539 
2540 	if (i > 0)
2541 		return 0;
2542 
2543 	file_magerror(ms, "Bad magic entry '%s'", line);
2544 	return -1;
2545 }
2546 
2547 /*
2548  * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2549  * magic[index - 1]
2550  */
2551 file_private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2552 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line,
2553     size_t len)
2554 {
2555 	return parse_extra(ms, me, line, len,
2556 	    CAST(off_t, offsetof(struct magic, apple)),
2557 	    sizeof(me->mp[0].apple), "APPLE", "!+-./?", 0);
2558 }
2559 
2560 /*
2561  * Parse a comma-separated list of extensions
2562  */
2563 file_private int
parse_ext(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2564 parse_ext(struct magic_set *ms, struct magic_entry *me, const char *line,
2565     size_t len)
2566 {
2567 	return parse_extra(ms, me, line, len,
2568 	    CAST(off_t, offsetof(struct magic, ext)),
2569 	    sizeof(me->mp[0].ext), "EXTENSION", ",!+-/@?_$&~", 0);
2570 	    /* & for b&w */
2571 	    /* ~ for journal~ */
2572 }
2573 
2574 /*
2575  * parse a MIME annotation line from magic file, put into magic[index - 1]
2576  * if valid
2577  */
2578 file_private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2579 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line,
2580     size_t len)
2581 {
2582 	return parse_extra(ms, me, line, len,
2583 	    CAST(off_t, offsetof(struct magic, mimetype)),
2584 	    sizeof(me->mp[0].mimetype), "MIME", "+-/.$?:{}", 1);
2585 }
2586 
2587 file_private int
check_format_type(const char * ptr,int type,const char ** estr)2588 check_format_type(const char *ptr, int type, const char **estr)
2589 {
2590 	int quad = 0, h;
2591 	size_t len, cnt;
2592 	if (*ptr == '\0') {
2593 		/* Missing format string; bad */
2594 		*estr = "missing format spec";
2595 		return -1;
2596 	}
2597 
2598 	switch (file_formats[type]) {
2599 	case FILE_FMT_QUAD:
2600 		quad = 1;
2601 		/*FALLTHROUGH*/
2602 	case FILE_FMT_NUM:
2603 		if (quad == 0) {
2604 			switch (type) {
2605 			case FILE_BYTE:
2606 				h = 2;
2607 				break;
2608 			case FILE_SHORT:
2609 			case FILE_BESHORT:
2610 			case FILE_LESHORT:
2611 				h = 1;
2612 				break;
2613 			case FILE_LONG:
2614 			case FILE_BELONG:
2615 			case FILE_LELONG:
2616 			case FILE_MELONG:
2617 			case FILE_LEID3:
2618 			case FILE_BEID3:
2619 			case FILE_INDIRECT:
2620 				h = 0;
2621 				break;
2622 			default:
2623 				fprintf(stderr, "Bad number format %d", type);
2624 				abort();
2625 			}
2626 		} else
2627 			h = 0;
2628 		while (*ptr && strchr("-.#", *ptr) != NULL)
2629 			ptr++;
2630 #define CHECKLEN() do { \
2631 	for (len = cnt = 0; isdigit(CAST(unsigned char, *ptr)); ptr++, cnt++) \
2632 		len = len * 10 + (*ptr - '0'); \
2633 	if (cnt > 5 || len > 1024) \
2634 		goto toolong; \
2635 } while (/*CONSTCOND*/0)
2636 
2637 		CHECKLEN();
2638 		if (*ptr == '.')
2639 			ptr++;
2640 		CHECKLEN();
2641 		if (quad) {
2642 			if (*ptr++ != 'l')
2643 				goto invalid;
2644 			if (*ptr++ != 'l')
2645 				goto invalid;
2646 		}
2647 
2648 		switch (*ptr++) {
2649 #ifdef STRICT_FORMAT 	/* "long" formats are int formats for us */
2650 		/* so don't accept the 'l' modifier */
2651 		case 'l':
2652 			switch (*ptr++) {
2653 			case 'i':
2654 			case 'd':
2655 			case 'u':
2656 			case 'o':
2657 			case 'x':
2658 			case 'X':
2659 				if (h == 0)
2660 					return 0;
2661 				/*FALLTHROUGH*/
2662 			default:
2663 				goto invalid;
2664 			}
2665 
2666 		/*
2667 		 * Don't accept h and hh modifiers. They make writing
2668 		 * magic entries more complicated, for very little benefit
2669 		 */
2670 		case 'h':
2671 			if (h-- <= 0)
2672 				goto invalid;
2673 			switch (*ptr++) {
2674 			case 'h':
2675 				if (h-- <= 0)
2676 					goto invalid;
2677 				switch (*ptr++) {
2678 				case 'i':
2679 				case 'd':
2680 				case 'u':
2681 				case 'o':
2682 				case 'x':
2683 				case 'X':
2684 					return 0;
2685 				default:
2686 					goto invalid;
2687 				}
2688 			case 'i':
2689 			case 'd':
2690 			case 'u':
2691 			case 'o':
2692 			case 'x':
2693 			case 'X':
2694 				if (h == 0)
2695 					return 0;
2696 				/*FALLTHROUGH*/
2697 			default:
2698 				goto invalid;
2699 			}
2700 #endif
2701 		case 'c':
2702 			if (h == 2)
2703 				return 0;
2704 			goto invalid;
2705 		case 'i':
2706 		case 'd':
2707 		case 'u':
2708 		case 'o':
2709 		case 'x':
2710 		case 'X':
2711 #ifdef STRICT_FORMAT
2712 			if (h == 0)
2713 				return 0;
2714 			/*FALLTHROUGH*/
2715 #else
2716 			return 0;
2717 #endif
2718 		default:
2719 			goto invalid;
2720 		}
2721 
2722 	case FILE_FMT_FLOAT:
2723 	case FILE_FMT_DOUBLE:
2724 		if (*ptr == '-')
2725 			ptr++;
2726 		if (*ptr == '.')
2727 			ptr++;
2728 		CHECKLEN();
2729 		if (*ptr == '.')
2730 			ptr++;
2731 		CHECKLEN();
2732 		switch (*ptr++) {
2733 		case 'e':
2734 		case 'E':
2735 		case 'f':
2736 		case 'F':
2737 		case 'g':
2738 		case 'G':
2739 			return 0;
2740 
2741 		default:
2742 			goto invalid;
2743 		}
2744 
2745 
2746 	case FILE_FMT_STR:
2747 		if (*ptr == '-')
2748 			ptr++;
2749 		while (isdigit(CAST(unsigned char, *ptr)))
2750 			ptr++;
2751 		if (*ptr == '.') {
2752 			ptr++;
2753 			while (isdigit(CAST(unsigned char , *ptr)))
2754 				ptr++;
2755 		}
2756 
2757 		switch (*ptr++) {
2758 		case 's':
2759 			return 0;
2760 		default:
2761 			goto invalid;
2762 		}
2763 
2764 	default:
2765 		/* internal error */
2766 		fprintf(stderr, "Bad file format %d", type);
2767 		abort();
2768 	}
2769 invalid:
2770 	*estr = "not valid";
2771 	return -1;
2772 toolong:
2773 	*estr = "too long";
2774 	return -1;
2775 }
2776 
2777 /*
2778  * Check that the optional printf format in description matches
2779  * the type of the magic.
2780  */
2781 file_private int
check_format(struct magic_set * ms,struct magic * m)2782 check_format(struct magic_set *ms, struct magic *m)
2783 {
2784 	char *ptr;
2785 	const char *estr;
2786 
2787 	for (ptr = m->desc; *ptr; ptr++)
2788 		if (*ptr == '%')
2789 			break;
2790 	if (*ptr == '\0') {
2791 		/* No format string; ok */
2792 		return 1;
2793 	}
2794 
2795 	assert(file_nformats == file_nnames);
2796 
2797 	if (m->type >= file_nformats) {
2798 		file_magwarn(ms, "Internal error inconsistency between "
2799 		    "m->type and format strings");
2800 		return -1;
2801 	}
2802 	if (file_formats[m->type] == FILE_FMT_NONE) {
2803 		file_magwarn(ms, "No format string for `%s' with description "
2804 		    "`%s'", m->desc, file_names[m->type]);
2805 		return -1;
2806 	}
2807 
2808 	ptr++;
2809 	if (check_format_type(ptr, m->type, &estr) == -1) {
2810 		/*
2811 		 * TODO: this error message is unhelpful if the format
2812 		 * string is not one character long
2813 		 */
2814 		file_magwarn(ms, "Printf format is %s for type "
2815 		    "`%s' in description `%s'", estr,
2816 		    file_names[m->type], m->desc);
2817 		return -1;
2818 	}
2819 
2820 	for (; *ptr; ptr++) {
2821 		if (*ptr == '%') {
2822 			file_magwarn(ms,
2823 			    "Too many format strings (should have at most one) "
2824 			    "for `%s' with description `%s'",
2825 			    file_names[m->type], m->desc);
2826 			return -1;
2827 		}
2828 	}
2829 	return 0;
2830 }
2831 
2832 /*
2833  * Read a numeric value from a pointer, into the value union of a magic
2834  * pointer, according to the magic type.  Update the string pointer to point
2835  * just after the number read.  Return 0 for success, non-zero for failure.
2836  */
2837 file_private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2838 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2839 {
2840 	char *ep;
2841 	uint64_t ull;
2842 	int y;
2843 
2844 	switch (m->type) {
2845 	case FILE_BESTRING16:
2846 	case FILE_LESTRING16:
2847 	case FILE_STRING:
2848 	case FILE_PSTRING:
2849 	case FILE_REGEX:
2850 	case FILE_SEARCH:
2851 	case FILE_NAME:
2852 	case FILE_USE:
2853 	case FILE_DER:
2854 	case FILE_OCTAL:
2855 		*p = getstr(ms, m, *p, action == FILE_COMPILE);
2856 		if (*p == NULL) {
2857 			if (ms->flags & MAGIC_CHECK)
2858 				file_magwarn(ms, "cannot get string from `%s'",
2859 				    m->value.s);
2860 			return -1;
2861 		}
2862 		if (m->type == FILE_REGEX) {
2863 			file_regex_t rx;
2864 			int rc =
2865 			    file_regcomp(ms, &rx, m->value.s, REG_EXTENDED);
2866 			if (rc == 0) {
2867 				file_regfree(&rx);
2868 			}
2869 			return rc ? -1 : 0;
2870 		}
2871 		return 0;
2872 	default:
2873 		if (m->reln == 'x')
2874 			return 0;
2875 		break;
2876 	}
2877 
2878 	switch (m->type) {
2879 	case FILE_FLOAT:
2880 	case FILE_BEFLOAT:
2881 	case FILE_LEFLOAT:
2882 		errno = 0;
2883 #ifdef HAVE_STRTOF
2884 		m->value.f = strtof(*p, &ep);
2885 #else
2886 		m->value.f = (float)strtod(*p, &ep);
2887 #endif
2888 		if (errno == 0)
2889 			*p = ep;
2890 		return 0;
2891 	case FILE_DOUBLE:
2892 	case FILE_BEDOUBLE:
2893 	case FILE_LEDOUBLE:
2894 		errno = 0;
2895 		m->value.d = strtod(*p, &ep);
2896 		if (errno == 0)
2897 			*p = ep;
2898 		return 0;
2899 	case FILE_GUID:
2900 		if (file_parse_guid(*p, m->value.guid) == -1)
2901 			return -1;
2902 		*p += FILE_GUID_SIZE - 1;
2903 		return 0;
2904 	default:
2905 		errno = 0;
2906 		ull = CAST(uint64_t, strtoull(*p, &ep, 0));
2907 		m->value.q = file_signextend(ms, m, ull);
2908 		if (*p == ep) {
2909 			file_magwarn(ms, "Unparsable number `%s'", *p);
2910 			return -1;
2911 		} else {
2912 			size_t ts = typesize(m->type);
2913 			uint64_t x;
2914 			const char *q;
2915 
2916 			if (ts == FILE_BADSIZE) {
2917 				file_magwarn(ms,
2918 				    "Expected numeric type got `%s'",
2919 				    type_tbl[m->type].name);
2920 				return -1;
2921 			}
2922 			for (q = *p; isspace(CAST(unsigned char, *q)); q++)
2923 				continue;
2924 			if (*q == '-' && ull != UINT64_MAX)
2925 				ull = -CAST(int64_t, ull);
2926 			switch (ts) {
2927 			case 1:
2928 				x = CAST(uint64_t, ull & ~0xffULL);
2929 				y = (x & ~0xffULL) != ~0xffULL;
2930 				break;
2931 			case 2:
2932 				x = CAST(uint64_t, ull & ~0xffffULL);
2933 				y = (x & ~0xffffULL) != ~0xffffULL;
2934 				break;
2935 			case 4:
2936 				x = CAST(uint64_t, ull & ~0xffffffffULL);
2937 				y = (x & ~0xffffffffULL) != ~0xffffffffULL;
2938 				break;
2939 			case 8:
2940 				x = 0;
2941 				y = 0;
2942 				break;
2943 			default:
2944 				fprintf(stderr, "Bad width %zu", ts);
2945 				abort();
2946 			}
2947 			if (x && y) {
2948 				file_magwarn(ms, "Overflow for numeric"
2949 				    " type `%s' value %#" PRIx64,
2950 				    type_tbl[m->type].name, ull);
2951 				return -1;
2952 			}
2953 		}
2954 		if (errno == 0) {
2955 			*p = ep;
2956 			eatsize(p);
2957 		}
2958 		return 0;
2959 	}
2960 }
2961 
2962 /*
2963  * Convert a string containing C character escapes.  Stop at an unescaped
2964  * space or tab.
2965  * Copy the converted version to "m->value.s", and the length in m->vallen.
2966  * Return updated scan pointer as function result. Warn if set.
2967  */
2968 file_private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)2969 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
2970 {
2971 	const char *origs = s;
2972 	char	*p = m->value.s;
2973 	size_t  plen = sizeof(m->value.s);
2974 	char 	*origp = p;
2975 	char	*pmax = p + plen - 1;
2976 	int	c;
2977 	int	val;
2978 	size_t	bracket_nesting = 0;
2979 
2980 	while ((c = *s++) != '\0') {
2981 		if (isspace(CAST(unsigned char, c)))
2982 			break;
2983 		if (p >= pmax) {
2984 			file_error(ms, 0, "string too long: `%s'", origs);
2985 			return NULL;
2986 		}
2987 		if (c != '\\') {
2988 		    if (c == '[') {
2989 			    bracket_nesting++;
2990 		    }
2991 		    if (c == ']' && bracket_nesting > 0) {
2992 			    bracket_nesting--;
2993 		    }
2994 		    *p++ = CAST(char, c);
2995 		    continue;
2996 		}
2997 		switch(c = *s++) {
2998 
2999 		case '\0':
3000 			if (warn)
3001 				file_magwarn(ms, "incomplete escape");
3002 			s--;
3003 			goto out;
3004 		case '.':
3005 			if (m->type == FILE_REGEX &&
3006 			    bracket_nesting == 0 && warn) {
3007 				file_magwarn(ms, "escaped dot ('.') found, "
3008 				    "use \\\\. instead");
3009 			}
3010 			warn = 0; /* already did */
3011 			/*FALLTHROUGH*/
3012 		case '\t':
3013 			if (warn) {
3014 				file_magwarn(ms,
3015 				    "escaped tab found, use \\\\t instead");
3016 				warn = 0;	/* already did */
3017 			}
3018 			/*FALLTHROUGH*/
3019 		default:
3020 			if (warn) {
3021 				if (isprint(CAST(unsigned char, c))) {
3022 					/* Allow escaping of
3023 					 * ``relations'' */
3024 					if (strchr("<>&^=!", c) == NULL
3025 					    && (m->type != FILE_REGEX ||
3026 					    strchr("[]().*?^$|{}", c)
3027 					    == NULL)) {
3028 						file_magwarn(ms, "no "
3029 						    "need to escape "
3030 						    "`%c'", c);
3031 					}
3032 				} else {
3033 					file_magwarn(ms,
3034 					    "unknown escape sequence: "
3035 					    "\\%03o", c);
3036 				}
3037 			}
3038 			/*FALLTHROUGH*/
3039 		/* space, perhaps force people to use \040? */
3040 		case ' ':
3041 #if 0
3042 		/*
3043 		 * Other things people escape, but shouldn't need to,
3044 		 * so we disallow them
3045 		 */
3046 		case '\'':
3047 		case '"':
3048 		case '?':
3049 #endif
3050 		/* Relations */
3051 		case '>':
3052 		case '<':
3053 		case '&':
3054 		case '^':
3055 		case '=':
3056 		case '!':
3057 		/* and backslash itself */
3058 		case '\\':
3059 			*p++ = CAST(char, c);
3060 			break;
3061 
3062 		case 'a':
3063 			*p++ = '\a';
3064 			break;
3065 
3066 		case 'b':
3067 			*p++ = '\b';
3068 			break;
3069 
3070 		case 'f':
3071 			*p++ = '\f';
3072 			break;
3073 
3074 		case 'n':
3075 			*p++ = '\n';
3076 			break;
3077 
3078 		case 'r':
3079 			*p++ = '\r';
3080 			break;
3081 
3082 		case 't':
3083 			*p++ = '\t';
3084 			break;
3085 
3086 		case 'v':
3087 			*p++ = '\v';
3088 			break;
3089 
3090 		/* \ and up to 3 octal digits */
3091 		case '0':
3092 		case '1':
3093 		case '2':
3094 		case '3':
3095 		case '4':
3096 		case '5':
3097 		case '6':
3098 		case '7':
3099 			val = c - '0';
3100 			c = *s++;  /* try for 2 */
3101 			if (c >= '0' && c <= '7') {
3102 				val = (val << 3) | (c - '0');
3103 				c = *s++;  /* try for 3 */
3104 				if (c >= '0' && c <= '7')
3105 					val = (val << 3) | (c-'0');
3106 				else
3107 					--s;
3108 			}
3109 			else
3110 				--s;
3111 			*p++ = CAST(char, val);
3112 			break;
3113 
3114 		/* \x and up to 2 hex digits */
3115 		case 'x':
3116 			val = 'x';	/* Default if no digits */
3117 			c = hextoint(*s++);	/* Get next char */
3118 			if (c >= 0) {
3119 				val = c;
3120 				c = hextoint(*s++);
3121 				if (c >= 0)
3122 					val = (val << 4) + c;
3123 				else
3124 					--s;
3125 			} else
3126 				--s;
3127 			*p++ = CAST(char, val);
3128 			break;
3129 		}
3130 	}
3131 	--s;
3132 out:
3133 	*p = '\0';
3134 	m->vallen = CAST(unsigned char, (p - origp));
3135 	if (m->type == FILE_PSTRING) {
3136 		size_t l =  file_pstring_length_size(ms, m);
3137 		if (l == FILE_BADSIZE)
3138 			return NULL;
3139 		m->vallen += CAST(unsigned char, l);
3140 	}
3141 	return s;
3142 }
3143 
3144 
3145 /* Single hex char to int; -1 if not a hex char. */
3146 file_private int
hextoint(int c)3147 hextoint(int c)
3148 {
3149 	if (!isascii(CAST(unsigned char, c)))
3150 		return -1;
3151 	if (isdigit(CAST(unsigned char, c)))
3152 		return c - '0';
3153 	if ((c >= 'a') && (c <= 'f'))
3154 		return c + 10 - 'a';
3155 	if (( c>= 'A') && (c <= 'F'))
3156 		return c + 10 - 'A';
3157 	return -1;
3158 }
3159 
3160 
3161 /*
3162  * Print a string containing C character escapes.
3163  */
3164 file_protected void
file_showstr(FILE * fp,const char * s,size_t len)3165 file_showstr(FILE *fp, const char *s, size_t len)
3166 {
3167 	char	c;
3168 
3169 	for (;;) {
3170 		if (len == FILE_BADSIZE) {
3171 			c = *s++;
3172 			if (c == '\0')
3173 				break;
3174 		}
3175 		else  {
3176 			if (len-- == 0)
3177 				break;
3178 			c = *s++;
3179 		}
3180 		if (c >= 040 && c <= 0176)	/* TODO isprint && !iscntrl */
3181 			(void) fputc(c, fp);
3182 		else {
3183 			(void) fputc('\\', fp);
3184 			switch (c) {
3185 			case '\a':
3186 				(void) fputc('a', fp);
3187 				break;
3188 
3189 			case '\b':
3190 				(void) fputc('b', fp);
3191 				break;
3192 
3193 			case '\f':
3194 				(void) fputc('f', fp);
3195 				break;
3196 
3197 			case '\n':
3198 				(void) fputc('n', fp);
3199 				break;
3200 
3201 			case '\r':
3202 				(void) fputc('r', fp);
3203 				break;
3204 
3205 			case '\t':
3206 				(void) fputc('t', fp);
3207 				break;
3208 
3209 			case '\v':
3210 				(void) fputc('v', fp);
3211 				break;
3212 
3213 			default:
3214 				(void) fprintf(fp, "%.3o", c & 0377);
3215 				break;
3216 			}
3217 		}
3218 	}
3219 }
3220 
3221 /*
3222  * eatsize(): Eat the size spec from a number [eg. 10UL]
3223  */
3224 file_private void
eatsize(const char ** p)3225 eatsize(const char **p)
3226 {
3227 	const char *l = *p;
3228 
3229 	if (LOWCASE(*l) == 'u')
3230 		l++;
3231 
3232 	switch (LOWCASE(*l)) {
3233 	case 'l':    /* long */
3234 	case 's':    /* short */
3235 	case 'h':    /* short */
3236 	case 'b':    /* char/byte */
3237 	case 'c':    /* char/byte */
3238 		l++;
3239 		/*FALLTHROUGH*/
3240 	default:
3241 		break;
3242 	}
3243 
3244 	*p = l;
3245 }
3246 
3247 /*
3248  * handle a buffer containing a compiled file.
3249  */
3250 file_private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)3251 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
3252 {
3253 	struct magic_map *map;
3254 
3255 	if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3256 		file_oomem(ms, sizeof(*map));
3257 		return NULL;
3258 	}
3259 	map->len = len;
3260 	map->p = buf;
3261 	map->type = MAP_TYPE_USER;
3262 	if (check_buffer(ms, map, "buffer") != 0) {
3263 		apprentice_unmap(map);
3264 		return NULL;
3265 	}
3266 	return map;
3267 }
3268 
3269 /*
3270  * handle a compiled file.
3271  */
3272 
3273 file_private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)3274 apprentice_map(struct magic_set *ms, const char *fn)
3275 {
3276 	int fd;
3277 	struct stat st;
3278 	char *dbname = NULL;
3279 	struct magic_map *map;
3280 	struct magic_map *rv = NULL;
3281 
3282 	fd = -1;
3283 	if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3284 		file_oomem(ms, sizeof(*map));
3285 		goto error;
3286 	}
3287 	map->type = MAP_TYPE_USER;	/* unspecified */
3288 
3289 	dbname = mkdbname(ms, fn, 0);
3290 	if (dbname == NULL)
3291 		goto error;
3292 
3293 	if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
3294 		goto error;
3295 
3296 	if (fstat(fd, &st) == -1) {
3297 		file_error(ms, errno, "cannot stat `%s'", dbname);
3298 		goto error;
3299 	}
3300 	if (st.st_size < 8 || st.st_size > maxoff_t()) {
3301 		file_error(ms, 0, "file `%s' is too %s", dbname,
3302 		    st.st_size < 8 ? "small" : "large");
3303 		goto error;
3304 	}
3305 
3306 	map->len = CAST(size_t, st.st_size);
3307 #ifdef QUICK
3308 	map->type = MAP_TYPE_MMAP;
3309 	if ((map->p = mmap(0, CAST(size_t, st.st_size), PROT_READ|PROT_WRITE,
3310 	    MAP_PRIVATE|MAP_FILE, fd, CAST(off_t, 0))) == MAP_FAILED) {
3311 		file_error(ms, errno, "cannot map `%s'", dbname);
3312 		goto error;
3313 	}
3314 #else
3315 	map->type = MAP_TYPE_MALLOC;
3316 	if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
3317 		file_oomem(ms, map->len);
3318 		goto error;
3319 	}
3320 	if (read(fd, map->p, map->len) != (ssize_t)map->len) {
3321 		file_badread(ms);
3322 		goto error;
3323 	}
3324 #endif
3325 	(void)close(fd);
3326 	fd = -1;
3327 
3328 	if (check_buffer(ms, map, dbname) != 0) {
3329 		goto error;
3330 	}
3331 #ifdef QUICK
3332 	if (mprotect(map->p, CAST(size_t, st.st_size), PROT_READ) == -1) {
3333 		file_error(ms, errno, "cannot mprotect `%s'", dbname);
3334 		goto error;
3335 	}
3336 #endif
3337 
3338 	free(dbname);
3339 	return map;
3340 
3341 error:
3342 	if (fd != -1)
3343 		(void)close(fd);
3344 	apprentice_unmap(map);
3345 	free(dbname);
3346 	return rv;
3347 }
3348 
3349 file_private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)3350 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
3351 {
3352 	uint32_t *ptr;
3353 	uint32_t entries, nentries;
3354 	uint32_t version;
3355 	int i, needsbyteswap;
3356 
3357 	ptr = CAST(uint32_t *, map->p);
3358 	if (*ptr != MAGICNO) {
3359 		if (swap4(*ptr) != MAGICNO) {
3360 			file_error(ms, 0, "bad magic in `%s'", dbname);
3361 			return -1;
3362 		}
3363 		needsbyteswap = 1;
3364 	} else
3365 		needsbyteswap = 0;
3366 	if (needsbyteswap)
3367 		version = swap4(ptr[1]);
3368 	else
3369 		version = ptr[1];
3370 	if (version != VERSIONNO) {
3371 		file_error(ms, 0, "File %s supports only version %d magic "
3372 		    "files. `%s' is version %d", VERSION,
3373 		    VERSIONNO, dbname, version);
3374 		return -1;
3375 	}
3376 	entries = CAST(uint32_t, map->len / sizeof(struct magic));
3377 	if ((entries * sizeof(struct magic)) != map->len) {
3378 		file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
3379 		    "a multiple of %" SIZE_T_FORMAT "u",
3380 		    dbname, map->len, sizeof(struct magic));
3381 		return -1;
3382 	}
3383 	map->magic[0] = CAST(struct magic *, map->p) + 1;
3384 	nentries = 0;
3385 	for (i = 0; i < MAGIC_SETS; i++) {
3386 		if (needsbyteswap)
3387 			map->nmagic[i] = swap4(ptr[i + 2]);
3388 		else
3389 			map->nmagic[i] = ptr[i + 2];
3390 		if (i != MAGIC_SETS - 1)
3391 			map->magic[i + 1] = map->magic[i] + map->nmagic[i];
3392 		nentries += map->nmagic[i];
3393 	}
3394 	if (entries != nentries + 1) {
3395 		file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
3396 		    dbname, entries, nentries + 1);
3397 		return -1;
3398 	}
3399 	if (needsbyteswap)
3400 		for (i = 0; i < MAGIC_SETS; i++)
3401 			byteswap(map->magic[i], map->nmagic[i]);
3402 	return 0;
3403 }
3404 
3405 /*
3406  * handle an mmaped file.
3407  */
3408 file_private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)3409 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
3410 {
3411 	static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
3412 	static const size_t m = sizeof(**map->magic);
3413 	int fd = -1;
3414 	size_t len;
3415 	char *dbname;
3416 	int rv = -1;
3417 	uint32_t i;
3418 	union {
3419 		struct magic m;
3420 		uint32_t h[2 + MAGIC_SETS];
3421 	} hdr;
3422 
3423 	dbname = mkdbname(ms, fn, 1);
3424 
3425 	if (dbname == NULL)
3426 		goto out;
3427 
3428 	if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
3429 	{
3430 		file_error(ms, errno, "cannot open `%s'", dbname);
3431 		goto out;
3432 	}
3433 	memset(&hdr, 0, sizeof(hdr));
3434 	hdr.h[0] = MAGICNO;
3435 	hdr.h[1] = VERSIONNO;
3436 	memcpy(hdr.h + 2, map->nmagic, nm);
3437 
3438 	if (write(fd, &hdr, sizeof(hdr)) != CAST(ssize_t, sizeof(hdr))) {
3439 		file_error(ms, errno, "error writing `%s'", dbname);
3440 		goto out2;
3441 	}
3442 
3443 	for (i = 0; i < MAGIC_SETS; i++) {
3444 		len = m * map->nmagic[i];
3445 		if (write(fd, map->magic[i], len) != CAST(ssize_t, len)) {
3446 			file_error(ms, errno, "error writing `%s'", dbname);
3447 			goto out2;
3448 		}
3449 	}
3450 
3451 	rv = 0;
3452 out2:
3453 	if (fd != -1)
3454 		(void)close(fd);
3455 out:
3456 	apprentice_unmap(map);
3457 	free(dbname);
3458 	return rv;
3459 }
3460 
3461 file_private const char ext[] = ".mgc";
3462 /*
3463  * make a dbname
3464  */
3465 file_private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3466 mkdbname(struct magic_set *ms, const char *fn, int strip)
3467 {
3468 	const char *p, *q;
3469 	char *buf;
3470 
3471 	if (strip) {
3472 		if ((p = strrchr(fn, '/')) != NULL)
3473 			fn = ++p;
3474 	}
3475 
3476 	for (q = fn; *q; q++)
3477 		continue;
3478 	/* Look for .mgc */
3479 	for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3480 		if (*p != *q)
3481 			break;
3482 
3483 	/* Did not find .mgc, restore q */
3484 	if (p >= ext)
3485 		while (*q)
3486 			q++;
3487 
3488 	q++;
3489 	/* Compatibility with old code that looked in .mime */
3490 	if (ms->flags & MAGIC_MIME) {
3491 		if (asprintf(&buf, "%.*s.mime%s", CAST(int, q - fn), fn, ext)
3492 		    < 0)
3493 			return NULL;
3494 		if (access(buf, R_OK) != -1) {
3495 			ms->flags &= MAGIC_MIME_TYPE;
3496 			return buf;
3497 		}
3498 		free(buf);
3499 	}
3500 	if (asprintf(&buf, "%.*s%s", CAST(int, q - fn), fn, ext) < 0)
3501 		return NULL;
3502 
3503 	/* Compatibility with old code that looked in .mime */
3504 	if (strstr(fn, ".mime") != NULL)
3505 		ms->flags &= MAGIC_MIME_TYPE;
3506 	return buf;
3507 }
3508 
3509 /*
3510  * Byteswap an mmap'ed file if needed
3511  */
3512 file_private void
byteswap(struct magic * magic,uint32_t nmagic)3513 byteswap(struct magic *magic, uint32_t nmagic)
3514 {
3515 	uint32_t i;
3516 	for (i = 0; i < nmagic; i++)
3517 		bs1(&magic[i]);
3518 }
3519 
3520 #if !defined(HAVE_BYTESWAP_H) && !defined(HAVE_SYS_BSWAP_H)
3521 /*
3522  * swap a short
3523  */
3524 file_private uint16_t
swap2(uint16_t sv)3525 swap2(uint16_t sv)
3526 {
3527 	uint16_t rv;
3528 	uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3529 	uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3530 	d[0] = s[1];
3531 	d[1] = s[0];
3532 	return rv;
3533 }
3534 
3535 /*
3536  * swap an int
3537  */
3538 file_private uint32_t
swap4(uint32_t sv)3539 swap4(uint32_t sv)
3540 {
3541 	uint32_t rv;
3542 	uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3543 	uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3544 	d[0] = s[3];
3545 	d[1] = s[2];
3546 	d[2] = s[1];
3547 	d[3] = s[0];
3548 	return rv;
3549 }
3550 
3551 /*
3552  * swap a quad
3553  */
3554 file_private uint64_t
swap8(uint64_t sv)3555 swap8(uint64_t sv)
3556 {
3557 	uint64_t rv;
3558 	uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3559 	uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3560 # if 0
3561 	d[0] = s[3];
3562 	d[1] = s[2];
3563 	d[2] = s[1];
3564 	d[3] = s[0];
3565 	d[4] = s[7];
3566 	d[5] = s[6];
3567 	d[6] = s[5];
3568 	d[7] = s[4];
3569 # else
3570 	d[0] = s[7];
3571 	d[1] = s[6];
3572 	d[2] = s[5];
3573 	d[3] = s[4];
3574 	d[4] = s[3];
3575 	d[5] = s[2];
3576 	d[6] = s[1];
3577 	d[7] = s[0];
3578 # endif
3579 	return rv;
3580 }
3581 #endif
3582 
3583 file_protected uintmax_t
file_varint2uintmax_t(const unsigned char * us,int t,size_t * l)3584 file_varint2uintmax_t(const unsigned char *us, int t, size_t *l)
3585 {
3586         uintmax_t x = 0;
3587         const unsigned char *c;
3588         if (t == FILE_LEVARINT) {
3589                 for (c = us; *c; c++) {
3590                         if ((*c & 0x80) == 0)
3591                                 break;
3592                 }
3593 		if (l)
3594 			*l = c - us + 1;
3595                 for (; c >= us; c--) {
3596                         x |= *c & 0x7f;
3597                         x <<= 7;
3598                 }
3599         } else {
3600                 for (c = us; *c; c++) {
3601 			x |= *c & 0x7f;
3602 			if ((*c & 0x80) == 0)
3603 				break;
3604 			x <<= 7;
3605                 }
3606 		if (l)
3607 			*l = c - us + 1;
3608         }
3609 	return x;
3610 }
3611 
3612 
3613 /*
3614  * byteswap a single magic entry
3615  */
3616 file_private void
bs1(struct magic * m)3617 bs1(struct magic *m)
3618 {
3619 	m->cont_level = swap2(m->cont_level);
3620 	m->offset = swap4(CAST(uint32_t, m->offset));
3621 	m->in_offset = swap4(CAST(uint32_t, m->in_offset));
3622 	m->lineno = swap4(CAST(uint32_t, m->lineno));
3623 	if (IS_STRING(m->type)) {
3624 		m->str_range = swap4(m->str_range);
3625 		m->str_flags = swap4(m->str_flags);
3626 	}
3627 	else {
3628 		m->value.q = swap8(m->value.q);
3629 		m->num_mask = swap8(m->num_mask);
3630 	}
3631 }
3632 
3633 file_protected size_t
file_pstring_length_size(struct magic_set * ms,const struct magic * m)3634 file_pstring_length_size(struct magic_set *ms, const struct magic *m)
3635 {
3636 	switch (m->str_flags & PSTRING_LEN) {
3637 	case PSTRING_1_LE:
3638 		return 1;
3639 	case PSTRING_2_LE:
3640 	case PSTRING_2_BE:
3641 		return 2;
3642 	case PSTRING_4_LE:
3643 	case PSTRING_4_BE:
3644 		return 4;
3645 	default:
3646 		file_error(ms, 0, "corrupt magic file "
3647 		    "(bad pascal string length %d)",
3648 		    m->str_flags & PSTRING_LEN);
3649 		return FILE_BADSIZE;
3650 	}
3651 }
3652 file_protected size_t
file_pstring_get_length(struct magic_set * ms,const struct magic * m,const char * ss)3653 file_pstring_get_length(struct magic_set *ms, const struct magic *m,
3654     const char *ss)
3655 {
3656 	size_t len = 0;
3657 	const unsigned char *s = RCAST(const unsigned char *, ss);
3658 	unsigned int s3, s2, s1, s0;
3659 
3660 	switch (m->str_flags & PSTRING_LEN) {
3661 	case PSTRING_1_LE:
3662 		len = *s;
3663 		break;
3664 	case PSTRING_2_LE:
3665 		s0 = s[0];
3666 		s1 = s[1];
3667 		len = (s1 << 8) | s0;
3668 		break;
3669 	case PSTRING_2_BE:
3670 		s0 = s[0];
3671 		s1 = s[1];
3672 		len = (s0 << 8) | s1;
3673 		break;
3674 	case PSTRING_4_LE:
3675 		s0 = s[0];
3676 		s1 = s[1];
3677 		s2 = s[2];
3678 		s3 = s[3];
3679 		len = (s3 << 24) | (s2 << 16) | (s1 << 8) | s0;
3680 		break;
3681 	case PSTRING_4_BE:
3682 		s0 = s[0];
3683 		s1 = s[1];
3684 		s2 = s[2];
3685 		s3 = s[3];
3686 		len = (s0 << 24) | (s1 << 16) | (s2 << 8) | s3;
3687 		break;
3688 	default:
3689 		file_error(ms, 0, "corrupt magic file "
3690 		    "(bad pascal string length %d)",
3691 		    m->str_flags & PSTRING_LEN);
3692 		return FILE_BADSIZE;
3693 	}
3694 
3695 	if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF) {
3696 		size_t l = file_pstring_length_size(ms, m);
3697 		if (l == FILE_BADSIZE)
3698 			return l;
3699 		len -= l;
3700 	}
3701 
3702 	return len;
3703 }
3704 
3705 file_protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3706 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3707 {
3708 	uint32_t i, j;
3709 	struct mlist *mlist, *ml;
3710 
3711 	mlist = ms->mlist[1];
3712 
3713 	for (ml = mlist->next; ml != mlist; ml = ml->next) {
3714 		struct magic *ma = ml->magic;
3715 		for (i = 0; i < ml->nmagic; i++) {
3716 			if (ma[i].type != FILE_NAME)
3717 				continue;
3718 			if (strcmp(ma[i].value.s, name) == 0) {
3719 				v->magic = &ma[i];
3720 				v->magic_rxcomp = &(ml->magic_rxcomp[i]);
3721 				for (j = i + 1; j < ml->nmagic; j++)
3722 				    if (ma[j].cont_level == 0)
3723 					    break;
3724 				v->nmagic = j - i;
3725 				return 0;
3726 			}
3727 		}
3728 	}
3729 	return -1;
3730 }
3731