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 1.376 2026/05/09 22:44:32 christos Exp $")
36 #endif /* lint */
37
38 #include "magic.h"
39 #include "swap.h"
40 #include <stdlib.h>
41 #ifdef HAVE_UNISTD_H
42 #include <unistd.h>
43 #endif
44 #include <stddef.h>
45 #include <string.h>
46 #include <assert.h>
47 #include <ctype.h>
48 #include <fcntl.h>
49 #ifdef QUICK
50 #include <sys/mman.h>
51 #endif
52 #include <dirent.h>
53 #include <limits.h>
54
55
56 #define EATAB {while (*l && isascii(CAST(unsigned char, *l)) && \
57 isspace(CAST(unsigned char, *l))) ++l;}
58 #define LOWCASE(l) (isupper(CAST(unsigned char, l)) ? \
59 tolower(CAST(unsigned char, l)) : (l))
60 /*
61 * Work around a bug in headers on Digital Unix.
62 * At least confirmed for: OSF1 V4.0 878
63 */
64 #if defined(__osf__) && defined(__DECC)
65 #ifdef MAP_FAILED
66 #undef MAP_FAILED
67 #endif
68 #endif
69
70 #ifndef MAP_FAILED
71 #define MAP_FAILED (void *) -1
72 #endif
73
74 #ifndef MAP_FILE
75 #define MAP_FILE 0
76 #endif
77
78 #define ALLOC_CHUNK CAST(size_t, 10)
79 #define ALLOC_INCR CAST(size_t, 200)
80
81 #define MAP_TYPE_USER 0
82 #define MAP_TYPE_MALLOC 1
83 #define MAP_TYPE_MMAP 2
84
85 struct magic_entry {
86 struct magic *mp;
87 uint32_t cont_count;
88 uint32_t max_count;
89 };
90
91 struct magic_entry_set {
92 struct magic_entry *me;
93 uint32_t count;
94 uint32_t max;
95 };
96
97 struct magic_map {
98 void *p;
99 size_t len;
100 int type;
101 struct magic *magic[MAGIC_SETS];
102 uint32_t nmagic[MAGIC_SETS];
103 };
104
105 file_private int file_formats[FILE_NAMES_SIZE];
106 file_private const size_t file_nformats = FILE_NAMES_SIZE;
107 file_protected const char *file_names[FILE_NAMES_SIZE];
108 file_protected const size_t file_nnames = FILE_NAMES_SIZE;
109
110 file_private int getvalue(struct magic_set *ms, struct magic *, const char **, int);
111 file_private int hextoint(int);
112 file_private const char *getstr(struct magic_set *, struct magic *, const char *,
113 int);
114 file_private int parse(struct magic_set *, struct magic_entry *, const char *,
115 const char *, size_t, size_t, int);
116 file_private void eatsize(const char **);
117 file_private int apprentice_1(struct magic_set *, const char *, int);
118 file_private ssize_t apprentice_magic_strength_1(const struct magic *);
119 file_private int apprentice_sort(const void *, const void *);
120 file_private void apprentice_list(struct mlist *, int );
121 file_private struct magic_map *apprentice_load(struct magic_set *,
122 const char *, int);
123 file_private struct mlist *mlist_alloc(void);
124 file_private void mlist_free_all(struct magic_set *);
125 file_private void mlist_free(struct mlist *);
126 file_private void byteswap(struct magic *, uint32_t);
127 file_private void bs1(struct magic *);
128
129 file_private char *mkdbname(struct magic_set *, const char *, int);
130 file_private struct magic_map *apprentice_buf(struct magic_set *, struct magic *,
131 size_t);
132 file_private struct magic_map *apprentice_map(struct magic_set *, const char *);
133 file_private int check_buffer(struct magic_set *, struct magic_map *, const char *);
134 file_private void apprentice_unmap(struct magic_map *);
135 file_private int apprentice_compile(struct magic_set *, struct magic_map *,
136 const char *);
137 file_private int check_format_type(const char *, int, const char **);
138 file_private int check_format(struct magic_set *, struct magic *);
139 file_private int get_op(char);
140 file_private int parse_mime(struct magic_set *, struct magic_entry *, const char *,
141 size_t);
142 file_private int parse_strength(struct magic_set *, struct magic_entry *,
143 const char *, size_t);
144 file_private int parse_apple(struct magic_set *, struct magic_entry *, const char *,
145 size_t);
146 file_private int parse_ext(struct magic_set *, struct magic_entry *, const char *,
147 size_t);
148
149
150 file_private size_t magicsize = sizeof(struct magic);
151
152 file_private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
153
154 file_private struct {
155 const char *name;
156 size_t len;
157 int (*fun)(struct magic_set *, struct magic_entry *, const char *,
158 size_t);
159 } bang[] = {
160 #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
161 DECLARE_FIELD(mime),
162 DECLARE_FIELD(apple),
163 DECLARE_FIELD(ext),
164 DECLARE_FIELD(strength),
165 #undef DECLARE_FIELD
166 { NULL, 0, NULL }
167 };
168
169 #ifdef COMPILE_ONLY
170
171 int main(int, char *[]);
172
173 int
main(int argc,char * argv[])174 main(int argc, char *argv[])
175 {
176 int ret;
177 struct magic_set *ms;
178 char *progname;
179
180 if ((progname = strrchr(argv[0], '/')) != NULL)
181 progname++;
182 else
183 progname = argv[0];
184
185 if (argc != 2) {
186 (void)fprintf(stderr, "Usage: %s file\n", progname);
187 return 1;
188 }
189
190 if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
191 (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
192 return 1;
193 }
194 ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
195 if (ret == 1)
196 (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
197 magic_close(ms);
198 return ret;
199 }
200 #endif /* COMPILE_ONLY */
201
202 struct type_tbl_s {
203 const char name[16];
204 const size_t len;
205 const int type;
206 const int format;
207 };
208
209 /*
210 * XXX - the actual Single UNIX Specification says that "long" means "long",
211 * as in the C data type, but we treat it as meaning "4-byte integer".
212 * Given that the OS X version of file 5.04 did the same, I guess that passes
213 * the actual test; having "long" be dependent on how big a "long" is on
214 * the machine running "file" is silly.
215 */
216 static const struct type_tbl_s type_tbl[] = {
217 # define XX(s) s, (sizeof(s) - 1)
218 # define XX_NULL "", 0
219 { XX("invalid"), FILE_INVALID, FILE_FMT_NONE },
220 { XX("byte"), FILE_BYTE, FILE_FMT_NUM },
221 { XX("short"), FILE_SHORT, FILE_FMT_NUM },
222 { XX("default"), FILE_DEFAULT, FILE_FMT_NONE },
223 { XX("long"), FILE_LONG, FILE_FMT_NUM },
224 { XX("string"), FILE_STRING, FILE_FMT_STR },
225 { XX("date"), FILE_DATE, FILE_FMT_STR },
226 { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM },
227 { XX("belong"), FILE_BELONG, FILE_FMT_NUM },
228 { XX("bedate"), FILE_BEDATE, FILE_FMT_STR },
229 { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM },
230 { XX("lelong"), FILE_LELONG, FILE_FMT_NUM },
231 { XX("ledate"), FILE_LEDATE, FILE_FMT_STR },
232 { XX("pstring"), FILE_PSTRING, FILE_FMT_STR },
233 { XX("ldate"), FILE_LDATE, FILE_FMT_STR },
234 { XX("beldate"), FILE_BELDATE, FILE_FMT_STR },
235 { XX("leldate"), FILE_LELDATE, FILE_FMT_STR },
236 { XX("regex"), FILE_REGEX, FILE_FMT_STR },
237 { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR },
238 { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR },
239 { XX("search"), FILE_SEARCH, FILE_FMT_STR },
240 { XX("medate"), FILE_MEDATE, FILE_FMT_STR },
241 { XX("meldate"), FILE_MELDATE, FILE_FMT_STR },
242 { XX("melong"), FILE_MELONG, FILE_FMT_NUM },
243 { XX("quad"), FILE_QUAD, FILE_FMT_QUAD },
244 { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD },
245 { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD },
246 { XX("qdate"), FILE_QDATE, FILE_FMT_STR },
247 { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR },
248 { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR },
249 { XX("qldate"), FILE_QLDATE, FILE_FMT_STR },
250 { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR },
251 { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR },
252 { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT },
253 { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT },
254 { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT },
255 { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE },
256 { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE },
257 { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE },
258 { XX("leid3"), FILE_LEID3, FILE_FMT_NUM },
259 { XX("beid3"), FILE_BEID3, FILE_FMT_NUM },
260 { XX("indirect"), FILE_INDIRECT, FILE_FMT_NUM },
261 { XX("qwdate"), FILE_QWDATE, FILE_FMT_STR },
262 { XX("leqwdate"), FILE_LEQWDATE, FILE_FMT_STR },
263 { XX("beqwdate"), FILE_BEQWDATE, FILE_FMT_STR },
264 { XX("name"), FILE_NAME, FILE_FMT_NONE },
265 { XX("use"), FILE_USE, FILE_FMT_NONE },
266 { XX("clear"), FILE_CLEAR, FILE_FMT_NONE },
267 { XX("der"), FILE_DER, FILE_FMT_STR },
268 { XX("guid"), FILE_GUID, FILE_FMT_STR },
269 { XX("leguid"), FILE_LEGUID, FILE_FMT_STR },
270 { XX("beguid"), FILE_BEGUID, FILE_FMT_STR },
271 { XX("offset"), FILE_OFFSET, FILE_FMT_QUAD },
272 { XX("bevarint"), FILE_BEVARINT, FILE_FMT_STR },
273 { XX("levarint"), FILE_LEVARINT, FILE_FMT_STR },
274 { XX("msdosdate"), FILE_MSDOSDATE, FILE_FMT_STR },
275 { XX("lemsdosdate"), FILE_LEMSDOSDATE, FILE_FMT_STR },
276 { XX("bemsdosdate"), FILE_BEMSDOSDATE, FILE_FMT_STR },
277 { XX("msdostime"), FILE_MSDOSTIME, FILE_FMT_STR },
278 { XX("lemsdostime"), FILE_LEMSDOSTIME, FILE_FMT_STR },
279 { XX("bemsdostime"), FILE_BEMSDOSTIME, FILE_FMT_STR },
280 { XX("octal"), FILE_OCTAL, FILE_FMT_STR },
281 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
282 };
283
284 /*
285 * These are not types, and cannot be preceded by "u" to make them
286 * unsigned.
287 */
288 static const struct type_tbl_s special_tbl[] = {
289 { XX("der"), FILE_DER, FILE_FMT_STR },
290 { XX("name"), FILE_NAME, FILE_FMT_STR },
291 { XX("use"), FILE_USE, FILE_FMT_STR },
292 { XX("octal"), FILE_OCTAL, FILE_FMT_STR },
293 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
294 };
295 # undef XX
296 # undef XX_NULL
297
298 file_private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)299 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
300 {
301 const struct type_tbl_s *p;
302
303 for (p = tbl; p->len; p++) {
304 if (strncmp(l, p->name, p->len) == 0) {
305 if (t)
306 *t = l + p->len;
307 break;
308 }
309 }
310 return p->type;
311 }
312
313 file_private off_t
maxoff_t(void)314 maxoff_t(void) {
315 if (/*CONSTCOND*/sizeof(off_t) == sizeof(int))
316 return CAST(off_t, INT_MAX);
317 if (/*CONSTCOND*/sizeof(off_t) == sizeof(long))
318 return CAST(off_t, LONG_MAX);
319 return 0x7fffffff;
320 }
321
322 file_private int
get_standard_integer_type(const char * l,const char ** t)323 get_standard_integer_type(const char *l, const char **t)
324 {
325 int type;
326
327 if (l[0] == '\0')
328 return FILE_INVALID;
329 if (l[1] == '\0')
330 return FILE_INVALID;
331 else if (isalpha(CAST(unsigned char, l[1]))) {
332 switch (l[1]) {
333 case 'C':
334 /* "dC" and "uC" */
335 type = FILE_BYTE;
336 break;
337 case 'S':
338 /* "dS" and "uS" */
339 type = FILE_SHORT;
340 break;
341 case 'I':
342 case 'L':
343 /*
344 * "dI", "dL", "uI", and "uL".
345 *
346 * XXX - the actual Single UNIX Specification says
347 * that "L" means "long", as in the C data type,
348 * but we treat it as meaning "4-byte integer".
349 * Given that the OS X version of file 5.04 did
350 * the same, I guess that passes the actual SUS
351 * validation suite; having "dL" be dependent on
352 * how big a "long" is on the machine running
353 * "file" is silly.
354 */
355 type = FILE_LONG;
356 break;
357 case 'Q':
358 /* "dQ" and "uQ" */
359 type = FILE_QUAD;
360 break;
361 default:
362 /* "d{anything else}", "u{anything else}" */
363 return FILE_INVALID;
364 }
365 l += 2;
366 } else if (isdigit(CAST(unsigned char, l[1]))) {
367 /*
368 * "d{num}" and "u{num}"; we only support {num} values
369 * of 1, 2, 4, and 8 - the Single UNIX Specification
370 * doesn't say anything about whether arbitrary
371 * values should be supported, but both the Solaris 10
372 * and OS X Mountain Lion versions of file passed the
373 * Single UNIX Specification validation suite, and
374 * neither of them support values bigger than 8 or
375 * non-power-of-2 values.
376 */
377 if (isdigit(CAST(unsigned char, l[2]))) {
378 /* Multi-digit, so > 9 */
379 return FILE_INVALID;
380 }
381 switch (l[1]) {
382 case '1':
383 type = FILE_BYTE;
384 break;
385 case '2':
386 type = FILE_SHORT;
387 break;
388 case '4':
389 type = FILE_LONG;
390 break;
391 case '8':
392 type = FILE_QUAD;
393 break;
394 default:
395 /* XXX - what about 3, 5, 6, or 7? */
396 return FILE_INVALID;
397 }
398 l += 2;
399 } else {
400 /*
401 * "d" or "u" by itself.
402 */
403 type = FILE_LONG;
404 ++l;
405 }
406 if (t)
407 *t = l;
408 return type;
409 }
410
411 file_private void
init_file_tables(void)412 init_file_tables(void)
413 {
414 static int done = 0;
415 const struct type_tbl_s *p;
416
417 if (done)
418 return;
419 done++;
420
421 for (p = type_tbl; p->len; p++) {
422 assert(p->type < FILE_NAMES_SIZE);
423 file_names[p->type] = p->name;
424 file_formats[p->type] = p->format;
425 }
426 assert(p - type_tbl == FILE_NAMES_SIZE);
427 }
428
429 file_private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)430 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
431 {
432 struct mlist *ml;
433
434 mlp->map = NULL;
435 if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
436 return -1;
437
438 ml->map = idx == 0 ? map : NULL;
439 ml->magic = map->magic[idx];
440 ml->nmagic = map->nmagic[idx];
441 if (ml->nmagic) {
442 ml->magic_rxcomp = CAST(file_regex_t **,
443 calloc(ml->nmagic, sizeof(*ml->magic_rxcomp)));
444 if (ml->magic_rxcomp == NULL) {
445 free(ml);
446 return -1;
447 }
448 } else
449 ml->magic_rxcomp = NULL;
450 mlp->prev->next = ml;
451 ml->prev = mlp->prev;
452 ml->next = mlp;
453 mlp->prev = ml;
454 return 0;
455 }
456
457 /*
458 * Handle one file or directory.
459 */
460 file_private int
apprentice_1(struct magic_set * ms,const char * fn,int action)461 apprentice_1(struct magic_set *ms, const char *fn, int action)
462 {
463 struct magic_map *map;
464 #ifndef COMPILE_ONLY
465 size_t i;
466 #endif
467
468 if (magicsize != FILE_MAGICSIZE) {
469 file_error(ms, 0, "magic element size %lu != %lu",
470 CAST(unsigned long, sizeof(*map->magic[0])),
471 CAST(unsigned long, FILE_MAGICSIZE));
472 return -1;
473 }
474
475 if (action == FILE_COMPILE) {
476 map = apprentice_load(ms, fn, action);
477 if (map == NULL)
478 return -1;
479 return apprentice_compile(ms, map, fn);
480 }
481
482 #ifndef COMPILE_ONLY
483 map = apprentice_map(ms, fn);
484 if (map == NULL) {
485 if (ms->flags & MAGIC_CHECK)
486 file_magwarn(ms, "using regular magic file `%s'", fn);
487 map = apprentice_load(ms, fn, action);
488 if (map == NULL)
489 return -1;
490 }
491
492 for (i = 0; i < MAGIC_SETS; i++) {
493 if (add_mlist(ms->mlist[i], map, i) == -1) {
494 /* failed to add to any list, free explicitly */
495 if (i == 0)
496 apprentice_unmap(map);
497 else
498 mlist_free_all(ms);
499 file_oomem(ms, sizeof(*ms->mlist[0]));
500 return -1;
501 }
502 }
503
504 if (action == FILE_LIST) {
505 for (i = 0; i < MAGIC_SETS; i++) {
506 printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
507 i);
508 apprentice_list(ms->mlist[i], BINTEST);
509 printf("Text patterns:\n");
510 apprentice_list(ms->mlist[i], TEXTTEST);
511 }
512 }
513 return 0;
514 #else
515 return 0;
516 #endif /* COMPILE_ONLY */
517 }
518
519 file_protected void
file_ms_free(struct magic_set * ms)520 file_ms_free(struct magic_set *ms)
521 {
522 size_t i;
523 if (ms == NULL)
524 return;
525 for (i = 0; i < MAGIC_SETS; i++)
526 mlist_free(ms->mlist[i]);
527 free(ms->o.pbuf);
528 free(ms->o.buf);
529 free(ms->c.li);
530 free(ms->fnamebuf);
531 #ifdef USE_C_LOCALE
532 freelocale(ms->c_lc_ctype);
533 #endif
534 free(ms);
535 }
536
537 file_protected struct magic_set *
file_ms_alloc(int flags)538 file_ms_alloc(int flags)
539 {
540 struct magic_set *ms;
541 size_t i, len;
542
543 if ((ms = CAST(struct magic_set *, calloc(CAST(size_t, 1u),
544 sizeof(*ms)))) == NULL)
545 return NULL;
546
547 if (magic_setflags(ms, flags) == -1) {
548 errno = EINVAL;
549 goto free;
550 }
551
552 ms->o.buf = ms->o.pbuf = NULL;
553 ms->o.blen = 0;
554 len = (ms->c.len = 10) * sizeof(*ms->c.li);
555
556 if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
557 goto free;
558
559 ms->event_flags = 0;
560 ms->error = -1;
561 for (i = 0; i < MAGIC_SETS; i++)
562 ms->mlist[i] = NULL;
563 ms->fnamebuf = NULL;
564 ms->file = "unknown";
565 ms->line = 0;
566 ms->magwarn = 0;
567 ms->indir_max = FILE_INDIR_MAX;
568 ms->name_max = FILE_NAME_MAX;
569 ms->elf_shnum_max = FILE_ELF_SHNUM_MAX;
570 ms->elf_shsize_max = FILE_ELF_SHSIZE_MAX;
571 ms->elf_phnum_max = FILE_ELF_PHNUM_MAX;
572 ms->elf_notes_max = FILE_ELF_NOTES_MAX;
573 ms->regex_max = FILE_REGEX_MAX;
574 ms->bytes_max = FILE_BYTES_MAX;
575 ms->encoding_max = FILE_ENCODING_MAX;
576 ms->magwarn_max = FILE_MAGWARN_MAX;
577 #ifdef USE_C_LOCALE
578 ms->c_lc_ctype = newlocale(LC_CTYPE_MASK, "C", 0);
579 assert(ms->c_lc_ctype != NULL);
580 #endif
581 return ms;
582 free:
583 free(ms);
584 return NULL;
585 }
586
587 file_private void
apprentice_unmap(struct magic_map * map)588 apprentice_unmap(struct magic_map *map)
589 {
590 size_t i;
591 char *p;
592 if (map == NULL)
593 return;
594
595 switch (map->type) {
596 case MAP_TYPE_USER:
597 break;
598 case MAP_TYPE_MALLOC:
599 p = CAST(char *, map->p);
600 for (i = 0; i < MAGIC_SETS; i++) {
601 char *b = RCAST(char *, map->magic[i]);
602 if (p != NULL && b >= p && b <= p + map->len)
603 continue;
604 free(b);
605 }
606 free(p);
607 break;
608 #ifdef QUICK
609 case MAP_TYPE_MMAP:
610 if (map->p && map->p != MAP_FAILED)
611 (void)munmap(map->p, map->len);
612 break;
613 #endif
614 default:
615 fprintf(stderr, "Bad map type %d", map->type);
616 abort();
617 }
618 free(map);
619 }
620
621 file_private struct mlist *
mlist_alloc(void)622 mlist_alloc(void)
623 {
624 struct mlist *mlist;
625 if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
626 return NULL;
627 }
628 mlist->next = mlist->prev = mlist;
629 return mlist;
630 }
631
632 file_private void
mlist_free_all(struct magic_set * ms)633 mlist_free_all(struct magic_set *ms)
634 {
635 size_t i;
636
637 for (i = 0; i < MAGIC_SETS; i++) {
638 mlist_free(ms->mlist[i]);
639 ms->mlist[i] = NULL;
640 }
641 }
642
643 file_private void
mlist_free_one(struct mlist * ml)644 mlist_free_one(struct mlist *ml)
645 {
646 size_t i;
647
648 if (ml->map)
649 apprentice_unmap(CAST(struct magic_map *, ml->map));
650
651 for (i = 0; i < ml->nmagic; ++i) {
652 if (ml->magic_rxcomp[i]) {
653 file_regfree(ml->magic_rxcomp[i]);
654 free(ml->magic_rxcomp[i]);
655 ml->magic_rxcomp[i] = NULL;
656 }
657 }
658 free(ml->magic_rxcomp);
659 ml->magic_rxcomp = NULL;
660 free(ml);
661 }
662
663 file_private void
mlist_free(struct mlist * mlist)664 mlist_free(struct mlist *mlist)
665 {
666 struct mlist *ml, *next;
667
668 if (mlist == NULL)
669 return;
670
671 for (ml = mlist->next; ml != mlist;) {
672 next = ml->next;
673 mlist_free_one(ml);
674 ml = next;
675 }
676 mlist_free_one(mlist);
677 }
678
679 #ifndef COMPILE_ONLY
680 /* void **bufs: an array of compiled magic files */
681 file_protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)682 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
683 size_t *sizes, size_t nbufs)
684 {
685 size_t i, j;
686 struct magic_map *map;
687
688 if (nbufs == 0)
689 return -1;
690
691 (void)file_reset(ms, 0);
692
693 init_file_tables();
694
695 for (i = 0; i < MAGIC_SETS; i++) {
696 mlist_free(ms->mlist[i]);
697 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
698 file_oomem(ms, sizeof(*ms->mlist[0]));
699 goto fail;
700 }
701 }
702
703 for (i = 0; i < nbufs; i++) {
704 map = apprentice_buf(ms, bufs[i], sizes[i]);
705 if (map == NULL)
706 goto fail;
707
708 for (j = 0; j < MAGIC_SETS; j++) {
709 if (add_mlist(ms->mlist[j], map, j) == -1) {
710 file_oomem(ms, sizeof(*ms->mlist[0]));
711 goto fail;
712 }
713 }
714 }
715
716 return 0;
717 fail:
718 mlist_free_all(ms);
719 return -1;
720 }
721 #endif
722
723 /* const char *fn: list of magic files and directories */
724 file_protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)725 file_apprentice(struct magic_set *ms, const char *fn, int action)
726 {
727 char *p;
728 int fileerr, errs = -1;
729 size_t i, j;
730
731 (void)file_reset(ms, 0);
732
733 if ((fn = magic_getpath(fn, action)) == NULL)
734 return -1;
735
736 init_file_tables();
737
738 free(ms->fnamebuf);
739 ms->file = NULL;
740 if ((ms->fnamebuf = strdup(fn)) == NULL) {
741 file_oomem(ms, strlen(fn));
742 return -1;
743 }
744
745 for (i = 0; i < MAGIC_SETS; i++) {
746 mlist_free(ms->mlist[i]);
747 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
748 file_oomem(ms, sizeof(*ms->mlist[0]));
749 for (j = 0; j < i; j++) {
750 mlist_free(ms->mlist[j]);
751 ms->mlist[j] = NULL;
752 }
753 return -1;
754 }
755 }
756 fn = ms->fnamebuf;
757
758 while (fn) {
759 p = CCAST(char *, strchr(fn, PATHSEP));
760 if (p)
761 *p++ = '\0';
762 if (*fn == '\0')
763 break;
764 fileerr = apprentice_1(ms, fn, action);
765 errs = MAX(errs, fileerr);
766 fn = p;
767 }
768
769 if (errs == -1) {
770 for (i = 0; i < MAGIC_SETS; i++) {
771 mlist_free(ms->mlist[i]);
772 ms->mlist[i] = NULL;
773 }
774 file_error(ms, 0, "could not find any valid magic files!");
775 return -1;
776 }
777
778 #if 0
779 /*
780 * Always leave the database loaded
781 */
782 if (action == FILE_LOAD)
783 return 0;
784
785 for (i = 0; i < MAGIC_SETS; i++) {
786 mlist_free(ms->mlist[i]);
787 ms->mlist[i] = NULL;
788 }
789 #endif
790
791 switch (action) {
792 case FILE_LOAD:
793 case FILE_COMPILE:
794 case FILE_CHECK:
795 case FILE_LIST:
796 return 0;
797 default:
798 file_error(ms, 0, "Invalid action %d", action);
799 return -1;
800 }
801 }
802
803 /*
804 * Compute the real length of a magic expression, for the purposes
805 * of determining how "strong" a magic expression is (approximating
806 * how specific its matches are):
807 * - magic characters count 0 unless escaped.
808 * - [] expressions count 1
809 * - {} expressions count 0
810 * - regular characters or escaped magic characters count 1
811 * - 0 length expressions count as one
812 */
813 file_private size_t
nonmagic(const char * str)814 nonmagic(const char *str)
815 {
816 const char *p;
817 size_t rv = 0;
818
819 for (p = str; *p; p++)
820 switch (*p) {
821 case '\\': /* Escaped anything counts 1 */
822 if (!*++p)
823 p--;
824 rv++;
825 continue;
826 case '?': /* Magic characters count 0 */
827 case '*':
828 case '.':
829 case '+':
830 case '^':
831 case '$':
832 continue;
833 case '[': /* Bracketed expressions count 1 the ']' */
834 while (*p && *p != ']')
835 p++;
836 p--;
837 continue;
838 case '{': /* Braced expressions count 0 */
839 while (*p && *p != '}')
840 p++;
841 if (!*p)
842 p--;
843 continue;
844 default: /* Anything else counts 1 */
845 rv++;
846 continue;
847 }
848
849 return rv == 0 ? 1 : rv; /* Return at least 1 */
850 }
851
852
853 file_private size_t
typesize(int type)854 typesize(int type)
855 {
856 switch (type) {
857 case FILE_BYTE:
858 return 1;
859
860 case FILE_SHORT:
861 case FILE_LESHORT:
862 case FILE_BESHORT:
863 case FILE_MSDOSDATE:
864 case FILE_BEMSDOSDATE:
865 case FILE_LEMSDOSDATE:
866 case FILE_MSDOSTIME:
867 case FILE_BEMSDOSTIME:
868 case FILE_LEMSDOSTIME:
869 return 2;
870
871 case FILE_LONG:
872 case FILE_LELONG:
873 case FILE_BELONG:
874 case FILE_MELONG:
875 return 4;
876
877 case FILE_DATE:
878 case FILE_LEDATE:
879 case FILE_BEDATE:
880 case FILE_MEDATE:
881 case FILE_LDATE:
882 case FILE_LELDATE:
883 case FILE_BELDATE:
884 case FILE_MELDATE:
885 case FILE_FLOAT:
886 case FILE_BEFLOAT:
887 case FILE_LEFLOAT:
888 case FILE_BEID3:
889 case FILE_LEID3:
890 return 4;
891
892 case FILE_QUAD:
893 case FILE_BEQUAD:
894 case FILE_LEQUAD:
895 case FILE_QDATE:
896 case FILE_LEQDATE:
897 case FILE_BEQDATE:
898 case FILE_QLDATE:
899 case FILE_LEQLDATE:
900 case FILE_BEQLDATE:
901 case FILE_QWDATE:
902 case FILE_LEQWDATE:
903 case FILE_BEQWDATE:
904 case FILE_DOUBLE:
905 case FILE_BEDOUBLE:
906 case FILE_LEDOUBLE:
907 case FILE_OFFSET:
908 case FILE_BEVARINT:
909 case FILE_LEVARINT:
910 return 8;
911
912 case FILE_LEGUID:
913 case FILE_BEGUID:
914 case FILE_GUID:
915 return 16;
916
917 default:
918 return FILE_BADSIZE;
919 }
920 }
921
922 /*
923 * Get weight of this magic entry, for sorting purposes.
924 */
925 file_private ssize_t
apprentice_magic_strength_1(const struct magic * m)926 apprentice_magic_strength_1(const struct magic *m)
927 {
928 #define MULT 10U
929 size_t ts, v;
930 ssize_t val = 2 * MULT; /* baseline strength */
931
932 switch (m->type) {
933 case FILE_DEFAULT: /* make sure this sorts last */
934 if (m->factor_op != FILE_FACTOR_OP_NONE) {
935 file_magwarn1("Unsupported factor_op in default %d",
936 m->factor_op);
937 }
938 return 0;
939
940 case FILE_BYTE:
941 case FILE_SHORT:
942 case FILE_LESHORT:
943 case FILE_BESHORT:
944 case FILE_LONG:
945 case FILE_LELONG:
946 case FILE_BELONG:
947 case FILE_MELONG:
948 case FILE_DATE:
949 case FILE_LEDATE:
950 case FILE_BEDATE:
951 case FILE_MEDATE:
952 case FILE_LDATE:
953 case FILE_LELDATE:
954 case FILE_BELDATE:
955 case FILE_MELDATE:
956 case FILE_FLOAT:
957 case FILE_BEFLOAT:
958 case FILE_LEFLOAT:
959 case FILE_QUAD:
960 case FILE_BEQUAD:
961 case FILE_LEQUAD:
962 case FILE_QDATE:
963 case FILE_LEQDATE:
964 case FILE_BEQDATE:
965 case FILE_QLDATE:
966 case FILE_LEQLDATE:
967 case FILE_BEQLDATE:
968 case FILE_QWDATE:
969 case FILE_LEQWDATE:
970 case FILE_BEQWDATE:
971 case FILE_DOUBLE:
972 case FILE_BEDOUBLE:
973 case FILE_LEDOUBLE:
974 case FILE_BEVARINT:
975 case FILE_LEVARINT:
976 case FILE_GUID:
977 case FILE_LEGUID:
978 case FILE_BEGUID:
979 case FILE_BEID3:
980 case FILE_LEID3:
981 case FILE_OFFSET:
982 case FILE_MSDOSDATE:
983 case FILE_BEMSDOSDATE:
984 case FILE_LEMSDOSDATE:
985 case FILE_MSDOSTIME:
986 case FILE_BEMSDOSTIME:
987 case FILE_LEMSDOSTIME:
988 ts = typesize(m->type);
989 if (ts == FILE_BADSIZE) {
990 (void)fprintf(stderr, "Bad size for type %d\n",
991 m->type);
992 abort();
993 }
994 val += ts * MULT;
995 break;
996
997 case FILE_PSTRING:
998 case FILE_STRING:
999 case FILE_OCTAL:
1000 val += m->vallen * MULT;
1001 break;
1002
1003 case FILE_BESTRING16:
1004 case FILE_LESTRING16:
1005 val += m->vallen * MULT / 2;
1006 break;
1007
1008 case FILE_SEARCH:
1009 if (m->vallen == 0)
1010 break;
1011 val += m->vallen * MAX(MULT / m->vallen, 1);
1012 break;
1013
1014 case FILE_REGEX:
1015 v = nonmagic(m->value.s);
1016 val += v * MAX(MULT / v, 1);
1017 break;
1018
1019 case FILE_INDIRECT:
1020 case FILE_NAME:
1021 case FILE_USE:
1022 case FILE_CLEAR:
1023 break;
1024
1025 case FILE_DER:
1026 val += MULT;
1027 break;
1028
1029 default:
1030 (void)fprintf(stderr, "Bad type %d\n", m->type);
1031 abort();
1032 }
1033
1034 switch (m->reln) {
1035 case 'x': /* matches anything penalize */
1036 case '!': /* matches almost anything penalize */
1037 val = 0;
1038 break;
1039
1040 case '=': /* Exact match, prefer */
1041 val += MULT;
1042 break;
1043
1044 case '>':
1045 case '<': /* comparison match reduce strength */
1046 val -= 2 * MULT;
1047 break;
1048
1049 case '^':
1050 case '&': /* masking bits, we could count them too */
1051 val -= MULT;
1052 break;
1053
1054 default:
1055 (void)fprintf(stderr, "Bad relation %c\n", m->reln);
1056 abort();
1057 }
1058
1059 return val;
1060 }
1061
1062
1063 /*ARGSUSED*/
1064 file_protected size_t
file_magic_strength(const struct magic * m,size_t nmagic)1065 file_magic_strength(const struct magic *m,
1066 size_t nmagic __attribute__((__unused__)))
1067 {
1068 ssize_t val = apprentice_magic_strength_1(m);
1069
1070 #ifdef notyet
1071 if (m->desc[0] == '\0') {
1072 size_t i;
1073 /*
1074 * Magic entries with no description get their continuations
1075 * added
1076 */
1077 for (i = 1; m[i].cont_level != 0 && i < MIN(nmagic, 3); i++) {
1078 ssize_t v = apprentice_magic_strength_1(&m[i]) >>
1079 (i + 1);
1080 val += v;
1081 if (m[i].desc[0] != '\0')
1082 break;
1083 }
1084 }
1085 #endif
1086
1087 switch (m->factor_op) {
1088 case FILE_FACTOR_OP_NONE:
1089 break;
1090 case FILE_FACTOR_OP_PLUS:
1091 val += m->factor;
1092 break;
1093 case FILE_FACTOR_OP_MINUS:
1094 val -= m->factor;
1095 break;
1096 case FILE_FACTOR_OP_TIMES:
1097 val *= m->factor;
1098 break;
1099 case FILE_FACTOR_OP_DIV:
1100 val /= m->factor;
1101 break;
1102 default:
1103 (void)fprintf(stderr, "Bad factor_op %u\n", m->factor_op);
1104 abort();
1105 }
1106
1107 if (val <= 0) /* ensure we only return 0 for FILE_DEFAULT */
1108 val = 1;
1109
1110 #ifndef notyet
1111 /*
1112 * Magic entries with no description get a bonus because they depend
1113 * on subsequent magic entries to print something.
1114 */
1115 if (m->desc[0] == '\0')
1116 val++;
1117 #endif
1118
1119 return val;
1120 }
1121
1122 /*
1123 * Sort callback for sorting entries by "strength" (basically length)
1124 */
1125 file_private int
apprentice_sort(const void * a,const void * b)1126 apprentice_sort(const void *a, const void *b)
1127 {
1128 const struct magic_entry *ma = CAST(const struct magic_entry *, a);
1129 const struct magic_entry *mb = CAST(const struct magic_entry *, b);
1130 size_t sa = file_magic_strength(ma->mp, ma->cont_count);
1131 size_t sb = file_magic_strength(mb->mp, mb->cont_count);
1132 if (sa == sb) {
1133 struct magic mpa = *ma->mp;
1134 struct magic mpb = *mb->mp;
1135 mpa.lineno = mpb.lineno = 0;
1136 int x = memcmp(&mpa, &mpb, sizeof(mpa));
1137 if (x == 0) {
1138 // Don't warn for DER
1139 if (mpa.type == FILE_DER)
1140 return 0;
1141 file_magwarn1("Duplicate magic entry `%s'",
1142 ma->mp->desc);
1143 #ifndef COMPILE_ONLY
1144 file_mdump(ma->mp);
1145 file_mdump(mb->mp);
1146 #endif
1147 return 0;
1148 }
1149 return x > 0 ? -1 : 1;
1150 }
1151 return sa > sb ? -1 : 1;
1152 }
1153
1154 /*
1155 * Shows sorted patterns list in the order which is used for the matching
1156 */
1157 file_private void
apprentice_list(struct mlist * mlist,int mode)1158 apprentice_list(struct mlist *mlist, int mode)
1159 {
1160 uint32_t magindex, descindex, mimeindex, lineindex;
1161 struct mlist *ml;
1162 for (ml = mlist->next; ml != mlist; ml = ml->next) {
1163 for (magindex = 0; magindex < ml->nmagic; magindex++) {
1164 struct magic *m = &ml->magic[magindex];
1165 if ((m->flag & mode) != mode) {
1166 /* Skip sub-tests */
1167 while (magindex + 1 < ml->nmagic &&
1168 ml->magic[magindex + 1].cont_level != 0)
1169 ++magindex;
1170 continue; /* Skip to next top-level test*/
1171 }
1172
1173 /*
1174 * Try to iterate over the tree until we find item with
1175 * description/mimetype.
1176 */
1177 lineindex = descindex = mimeindex = magindex;
1178 for (; magindex + 1 < ml->nmagic &&
1179 ml->magic[magindex + 1].cont_level != 0;
1180 magindex++) {
1181 uint32_t mi = magindex + 1;
1182 if (*ml->magic[descindex].desc == '\0'
1183 && *ml->magic[mi].desc)
1184 descindex = mi;
1185 if (*ml->magic[mimeindex].mimetype == '\0'
1186 && *ml->magic[mi].mimetype)
1187 mimeindex = mi;
1188 }
1189
1190 printf("Strength = %3" SIZE_T_FORMAT "u@%u: %s [%s]\n",
1191 file_magic_strength(m, ml->nmagic - magindex),
1192 ml->magic[lineindex].lineno,
1193 ml->magic[descindex].desc,
1194 ml->magic[mimeindex].mimetype);
1195 }
1196 }
1197 }
1198
1199 file_private void
set_test_type(struct magic * mstart,struct magic * m)1200 set_test_type(struct magic *mstart, struct magic *m)
1201 {
1202 switch (m->type) {
1203 case FILE_BYTE:
1204 case FILE_SHORT:
1205 case FILE_LONG:
1206 case FILE_DATE:
1207 case FILE_BESHORT:
1208 case FILE_BELONG:
1209 case FILE_BEDATE:
1210 case FILE_LESHORT:
1211 case FILE_LELONG:
1212 case FILE_LEDATE:
1213 case FILE_LDATE:
1214 case FILE_BELDATE:
1215 case FILE_LELDATE:
1216 case FILE_MEDATE:
1217 case FILE_MELDATE:
1218 case FILE_MELONG:
1219 case FILE_QUAD:
1220 case FILE_LEQUAD:
1221 case FILE_BEQUAD:
1222 case FILE_QDATE:
1223 case FILE_LEQDATE:
1224 case FILE_BEQDATE:
1225 case FILE_QLDATE:
1226 case FILE_LEQLDATE:
1227 case FILE_BEQLDATE:
1228 case FILE_QWDATE:
1229 case FILE_LEQWDATE:
1230 case FILE_BEQWDATE:
1231 case FILE_FLOAT:
1232 case FILE_BEFLOAT:
1233 case FILE_LEFLOAT:
1234 case FILE_DOUBLE:
1235 case FILE_BEDOUBLE:
1236 case FILE_LEDOUBLE:
1237 case FILE_BEVARINT:
1238 case FILE_LEVARINT:
1239 case FILE_DER:
1240 case FILE_GUID:
1241 case FILE_LEGUID:
1242 case FILE_BEGUID:
1243 case FILE_OFFSET:
1244 case FILE_MSDOSDATE:
1245 case FILE_BEMSDOSDATE:
1246 case FILE_LEMSDOSDATE:
1247 case FILE_MSDOSTIME:
1248 case FILE_BEMSDOSTIME:
1249 case FILE_LEMSDOSTIME:
1250 case FILE_OCTAL:
1251 mstart->flag |= BINTEST;
1252 break;
1253 case FILE_STRING:
1254 case FILE_PSTRING:
1255 case FILE_BESTRING16:
1256 case FILE_LESTRING16:
1257 case FILE_REGEX:
1258 case FILE_SEARCH:
1259 /* Check for override */
1260 if (mstart->str_flags & STRING_BINTEST)
1261 mstart->flag |= BINTEST;
1262 if (mstart->str_flags & STRING_TEXTTEST)
1263 mstart->flag |= TEXTTEST;
1264
1265 if (mstart->flag & (TEXTTEST|BINTEST))
1266 break;
1267
1268 /*
1269 * XXX: Compatibility: For string types assume binary match
1270 * in reality it is better in the long term to change all
1271 * the magic to be string/b where appropriate
1272 */
1273 if (m->type != FILE_REGEX && m->type != FILE_SEARCH) {
1274 mstart->flag |= BINTEST;
1275 break;
1276 }
1277
1278 /* binary test if pattern is not text */
1279 if (file_looks_utf8(m->value.us, CAST(size_t, m->vallen), NULL,
1280 NULL) <= 0)
1281 mstart->flag |= BINTEST;
1282 else
1283 mstart->flag |= TEXTTEST;
1284 break;
1285 case FILE_DEFAULT:
1286 /* can't deduce anything; we shouldn't see this at the
1287 top level anyway */
1288 break;
1289 case FILE_INVALID:
1290 default:
1291 /* invalid search type, but no need to complain here */
1292 break;
1293 }
1294 }
1295
1296 file_private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1297 addentry(struct magic_set *ms, struct magic_entry *me,
1298 struct magic_entry_set *mset)
1299 {
1300 size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1301 if (mset[i].me == NULL || mset[i].count == mset[i].max) {
1302 struct magic_entry *mp;
1303
1304 size_t incr = mset[i].max + ALLOC_INCR;
1305 if ((mp = CAST(struct magic_entry *,
1306 realloc(mset[i].me, sizeof(*mp) * incr))) ==
1307 NULL) {
1308 file_oomem(ms, sizeof(*mp) * incr);
1309 return -1;
1310 }
1311 (void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1312 ALLOC_INCR);
1313 mset[i].me = mp;
1314 mset[i].max = CAST(uint32_t, incr);
1315 assert(mset[i].max == incr);
1316 }
1317 mset[i].me[mset[i].count++] = *me;
1318 memset(me, 0, sizeof(*me));
1319 return 0;
1320 }
1321
1322 /*
1323 * Load and parse one file.
1324 */
1325 file_private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1326 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1327 struct magic_entry_set *mset)
1328 {
1329 size_t lineno = 0, llen = 0;
1330 char *line = NULL;
1331 ssize_t len;
1332 struct magic_entry me;
1333
1334 FILE *f = fopen(ms->file = fn, "r");
1335 if (f == NULL) {
1336 if (errno != ENOENT)
1337 file_error(ms, errno, "cannot read magic file `%s'",
1338 fn);
1339 (*errs)++;
1340 return;
1341 }
1342
1343 memset(&me, 0, sizeof(me));
1344 /* read and parse this file */
1345 for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1346 ms->line++) {
1347 if (ms->magwarn >= ms->magwarn_max)
1348 break;
1349 if (len == 0) /* null line, garbage, etc */
1350 continue;
1351 if (line[len - 1] == '\n') {
1352 lineno++;
1353 line[len - 1] = '\0'; /* delete newline */
1354 }
1355 switch (line[0]) {
1356 case '\0': /* empty, do not parse */
1357 case '#': /* comment, do not parse */
1358 continue;
1359 case '!':
1360 if (line[1] == ':') {
1361 size_t i;
1362
1363 for (i = 0; bang[i].name != NULL; i++) {
1364 if (CAST(size_t, len - 2) > bang[i].len &&
1365 memcmp(bang[i].name, line + 2,
1366 bang[i].len) == 0)
1367 break;
1368 }
1369 if (bang[i].name == NULL) {
1370 file_error(ms, 0,
1371 "Unknown !: entry `%s'", line);
1372 (*errs)++;
1373 continue;
1374 }
1375 if (me.mp == NULL) {
1376 file_error(ms, 0,
1377 "No current entry for :!%s type",
1378 bang[i].name);
1379 (*errs)++;
1380 continue;
1381 }
1382 if ((*bang[i].fun)(ms, &me,
1383 line + bang[i].len + 2,
1384 len - bang[i].len - 2) != 0) {
1385 (*errs)++;
1386 continue;
1387 }
1388 continue;
1389 }
1390 /*FALLTHROUGH*/
1391 default:
1392 again:
1393 switch (parse(ms, &me, fn, line, llen, lineno, action)) {
1394 case 0:
1395 continue;
1396 case 1:
1397 (void)addentry(ms, &me, mset);
1398 goto again;
1399 default:
1400 (*errs)++;
1401 break;
1402 }
1403 }
1404 }
1405 if (me.mp)
1406 (void)addentry(ms, &me, mset);
1407 free(line);
1408 (void)fclose(f);
1409 }
1410
1411 /*
1412 * parse a file or directory of files
1413 * const char *fn: name of magic file or directory
1414 */
1415 file_private int
cmpstrp(const void * p1,const void * p2)1416 cmpstrp(const void *p1, const void *p2)
1417 {
1418 return strcmp(*RCAST(char *const *, p1), *RCAST(char *const *, p2));
1419 }
1420
1421
1422 file_private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1423 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1424 uint32_t starttest)
1425 {
1426 static const char text[] = "text";
1427 static const char binary[] = "binary";
1428 static const size_t len = sizeof(text);
1429
1430 uint32_t i = starttest;
1431
1432 do {
1433 set_test_type(me[starttest].mp, me[i].mp);
1434 if ((ms->flags & MAGIC_DEBUG) == 0)
1435 continue;
1436 (void)fprintf(stderr, "%s%s%s: %s\n",
1437 me[i].mp->mimetype,
1438 me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1439 me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1440 me[i].mp->flag & BINTEST ? binary : text);
1441 if (me[i].mp->flag & BINTEST) {
1442 char *p = strstr(me[i].mp->desc, text);
1443 if (p && (p == me[i].mp->desc ||
1444 isspace(CAST(unsigned char, p[-1]))) &&
1445 (p + len - me[i].mp->desc == MAXstring
1446 || (p[len] == '\0' ||
1447 isspace(CAST(unsigned char, p[len])))))
1448 (void)fprintf(stderr, "*** Possible "
1449 "binary test for text type\n");
1450 }
1451 } while (++i < nme && me[i].mp->cont_level != 0);
1452 return i;
1453 }
1454
1455 file_private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1456 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1457 {
1458 uint32_t i;
1459 for (i = 0; i < nme; i++) {
1460 if (me[i].mp->cont_level == 0 &&
1461 me[i].mp->type == FILE_DEFAULT) {
1462 while (++i < nme)
1463 if (me[i].mp->cont_level == 0)
1464 break;
1465 if (i != nme) {
1466 /* XXX - Ugh! */
1467 ms->line = me[i].mp->lineno;
1468 file_magwarn(ms,
1469 "level 0 \"default\" did not sort last");
1470 }
1471 return;
1472 }
1473 }
1474 }
1475
1476 file_private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1477 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1478 struct magic **ma, uint32_t *nma)
1479 {
1480 uint32_t i;
1481 size_t mentrycount = 0;
1482 size_t slen;
1483
1484 for (i = 0; i < nme; i++)
1485 mentrycount += me[i].cont_count;
1486
1487 if (mentrycount > UINT32_MAX / sizeof(**ma)) {
1488 file_error(ms, 0, "too many magic entries (%zu)", mentrycount);
1489 return -1;
1490 }
1491
1492 if (mentrycount == 0) {
1493 *ma = NULL;
1494 *nma = 0;
1495 return 0;
1496 }
1497
1498 slen = sizeof(**ma) * mentrycount;
1499 if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1500 file_oomem(ms, slen);
1501 return -1;
1502 }
1503
1504 mentrycount = 0;
1505 for (i = 0; i < nme; i++) {
1506 (void)memcpy(*ma + mentrycount, me[i].mp,
1507 me[i].cont_count * sizeof(**ma));
1508 mentrycount += me[i].cont_count;
1509 }
1510 *nma = mentrycount;
1511 return 0;
1512 }
1513
1514 file_private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1515 magic_entry_free(struct magic_entry *me, uint32_t nme)
1516 {
1517 uint32_t i;
1518 if (me == NULL)
1519 return;
1520 for (i = 0; i < nme; i++)
1521 free(me[i].mp);
1522 free(me);
1523 }
1524
1525 file_private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1526 apprentice_load(struct magic_set *ms, const char *fn, int action)
1527 {
1528 int errs = 0;
1529 uint32_t i, j;
1530 size_t files = 0, maxfiles = 0;
1531 char **filearr = NULL, *mfn;
1532 struct stat st;
1533 struct magic_map *map;
1534 struct magic_entry_set mset[MAGIC_SETS];
1535 DIR *dir;
1536 struct dirent *d;
1537
1538 memset(mset, 0, sizeof(mset));
1539 ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */
1540
1541
1542 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1543 {
1544 file_oomem(ms, sizeof(*map));
1545 return NULL;
1546 }
1547 map->type = MAP_TYPE_MALLOC;
1548
1549 /* print silly verbose header for USG compat. */
1550 if (action == FILE_CHECK)
1551 (void)fprintf(stderr, "%s\n", usg_hdr);
1552
1553 /* load directory or file */
1554 if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1555 dir = opendir(fn);
1556 if (!dir) {
1557 errs++;
1558 goto out;
1559 }
1560 while ((d = readdir(dir)) != NULL) {
1561 if (d->d_name[0] == '.')
1562 continue;
1563 if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1564 file_oomem(ms,
1565 strlen(fn) + strlen(d->d_name) + 2);
1566 errs++;
1567 closedir(dir);
1568 goto out;
1569 }
1570 if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1571 free(mfn);
1572 continue;
1573 }
1574 if (files >= maxfiles) {
1575 size_t mlen;
1576 char **nfilearr;
1577 maxfiles = (maxfiles + 1) * 2;
1578 mlen = maxfiles * sizeof(*filearr);
1579 if ((nfilearr = CAST(char **,
1580 realloc(filearr, mlen))) == NULL) {
1581 file_oomem(ms, mlen);
1582 free(mfn);
1583 closedir(dir);
1584 errs++;
1585 goto out;
1586 }
1587 filearr = nfilearr;
1588 }
1589 filearr[files++] = mfn;
1590 }
1591 closedir(dir);
1592 if (filearr) {
1593 qsort(filearr, files, sizeof(*filearr), cmpstrp);
1594 for (i = 0; i < files; i++) {
1595 load_1(ms, action, filearr[i], &errs, mset);
1596 free(filearr[i]);
1597 }
1598 free(filearr);
1599 filearr = NULL;
1600 }
1601 } else
1602 load_1(ms, action, fn, &errs, mset);
1603 if (errs)
1604 goto out;
1605
1606 for (j = 0; j < MAGIC_SETS; j++) {
1607 /* Set types of tests */
1608 for (i = 0; i < mset[j].count; ) {
1609 if (mset[j].me[i].mp->cont_level != 0) {
1610 i++;
1611 continue;
1612 }
1613 i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1614 }
1615 if (mset[j].me)
1616 qsort(mset[j].me, mset[j].count, sizeof(*mset[0].me),
1617 apprentice_sort);
1618
1619 /*
1620 * Make sure that any level 0 "default" line is last
1621 * (if one exists).
1622 */
1623 set_last_default(ms, mset[j].me, mset[j].count);
1624
1625 /* coalesce per file arrays into a single one, if needed */
1626 if (mset[j].count == 0)
1627 continue;
1628
1629 if (coalesce_entries(ms, mset[j].me, mset[j].count,
1630 &map->magic[j], &map->nmagic[j]) == -1) {
1631 errs++;
1632 goto out;
1633 }
1634 }
1635
1636 out:
1637 free(filearr);
1638 for (j = 0; j < MAGIC_SETS; j++)
1639 magic_entry_free(mset[j].me, mset[j].count);
1640
1641 if (errs) {
1642 apprentice_unmap(map);
1643 return NULL;
1644 }
1645 return map;
1646 }
1647
1648 /*
1649 * extend the sign bit if the comparison is to be signed
1650 */
1651 file_protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1652 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1653 {
1654 if (!(m->flag & UNSIGNED)) {
1655 switch(m->type) {
1656 /*
1657 * Do not remove the casts below. They are
1658 * vital. When later compared with the data,
1659 * the sign extension must have happened.
1660 */
1661 case FILE_BYTE:
1662 v = CAST(signed char, v);
1663 break;
1664 case FILE_SHORT:
1665 case FILE_BESHORT:
1666 case FILE_LESHORT:
1667 v = CAST(short, v);
1668 break;
1669 case FILE_DATE:
1670 case FILE_BEDATE:
1671 case FILE_LEDATE:
1672 case FILE_MEDATE:
1673 case FILE_LDATE:
1674 case FILE_BELDATE:
1675 case FILE_LELDATE:
1676 case FILE_MELDATE:
1677 case FILE_LONG:
1678 case FILE_BELONG:
1679 case FILE_LELONG:
1680 case FILE_MELONG:
1681 case FILE_FLOAT:
1682 case FILE_BEFLOAT:
1683 case FILE_LEFLOAT:
1684 case FILE_MSDOSDATE:
1685 case FILE_BEMSDOSDATE:
1686 case FILE_LEMSDOSDATE:
1687 case FILE_MSDOSTIME:
1688 case FILE_BEMSDOSTIME:
1689 case FILE_LEMSDOSTIME:
1690 v = CAST(int32_t, v);
1691 break;
1692 case FILE_QUAD:
1693 case FILE_BEQUAD:
1694 case FILE_LEQUAD:
1695 case FILE_QDATE:
1696 case FILE_QLDATE:
1697 case FILE_QWDATE:
1698 case FILE_BEQDATE:
1699 case FILE_BEQLDATE:
1700 case FILE_BEQWDATE:
1701 case FILE_LEQDATE:
1702 case FILE_LEQLDATE:
1703 case FILE_LEQWDATE:
1704 case FILE_DOUBLE:
1705 case FILE_BEDOUBLE:
1706 case FILE_LEDOUBLE:
1707 case FILE_OFFSET:
1708 case FILE_BEVARINT:
1709 case FILE_LEVARINT:
1710 v = CAST(int64_t, v);
1711 break;
1712 case FILE_STRING:
1713 case FILE_PSTRING:
1714 case FILE_BESTRING16:
1715 case FILE_LESTRING16:
1716 case FILE_REGEX:
1717 case FILE_SEARCH:
1718 case FILE_DEFAULT:
1719 case FILE_INDIRECT:
1720 case FILE_NAME:
1721 case FILE_USE:
1722 case FILE_CLEAR:
1723 case FILE_DER:
1724 case FILE_GUID:
1725 case FILE_LEGUID:
1726 case FILE_BEGUID:
1727 case FILE_OCTAL:
1728 break;
1729 default:
1730 if (ms->flags & MAGIC_CHECK)
1731 file_magwarn(ms, "cannot happen: m->type=%d\n",
1732 m->type);
1733 return FILE_BADSIZE;
1734 }
1735 }
1736 return v;
1737 }
1738
1739 file_private int
string_modifier_check(struct magic_set * ms,struct magic * m)1740 string_modifier_check(struct magic_set *ms, struct magic *m)
1741 {
1742 if ((ms->flags & MAGIC_CHECK) == 0)
1743 return 0;
1744
1745 if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1746 (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1747 file_magwarn(ms,
1748 "'/BHhLl' modifiers are only allowed for pascal strings\n");
1749 return -1;
1750 }
1751 switch (m->type) {
1752 case FILE_BESTRING16:
1753 case FILE_LESTRING16:
1754 if (m->str_flags != 0) {
1755 file_magwarn(ms,
1756 "no modifiers allowed for 16-bit strings\n");
1757 return -1;
1758 }
1759 break;
1760 case FILE_STRING:
1761 case FILE_PSTRING:
1762 if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1763 file_magwarn(ms,
1764 "'/%c' only allowed on regex and search\n",
1765 CHAR_REGEX_OFFSET_START);
1766 return -1;
1767 }
1768 break;
1769 case FILE_SEARCH:
1770 if (m->str_range == 0) {
1771 file_magwarn(ms,
1772 "missing range; defaulting to %d\n",
1773 STRING_DEFAULT_RANGE);
1774 m->str_range = STRING_DEFAULT_RANGE;
1775 return -1;
1776 }
1777 break;
1778 case FILE_REGEX:
1779 if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1780 file_magwarn(ms, "'/%c' not allowed on regex\n",
1781 CHAR_COMPACT_WHITESPACE);
1782 return -1;
1783 }
1784 if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1785 file_magwarn(ms, "'/%c' not allowed on regex\n",
1786 CHAR_COMPACT_OPTIONAL_WHITESPACE);
1787 return -1;
1788 }
1789 break;
1790 default:
1791 file_magwarn(ms, "coding error: m->type=%d\n",
1792 m->type);
1793 return -1;
1794 }
1795 return 0;
1796 }
1797
1798 file_private int
get_op(char c)1799 get_op(char c)
1800 {
1801 switch (c) {
1802 case '&':
1803 return FILE_OPAND;
1804 case '|':
1805 return FILE_OPOR;
1806 case '^':
1807 return FILE_OPXOR;
1808 case '+':
1809 return FILE_OPADD;
1810 case '-':
1811 return FILE_OPMINUS;
1812 case '*':
1813 return FILE_OPMULTIPLY;
1814 case '/':
1815 return FILE_OPDIVIDE;
1816 case '%':
1817 return FILE_OPMODULO;
1818 default:
1819 return -1;
1820 }
1821 }
1822
1823 #ifdef ENABLE_CONDITIONALS
1824 file_private int
get_cond(const char * l,const char ** t)1825 get_cond(const char *l, const char **t)
1826 {
1827 static const struct cond_tbl_s {
1828 char name[8];
1829 size_t len;
1830 int cond;
1831 } cond_tbl[] = {
1832 { "if", 2, COND_IF },
1833 { "elif", 4, COND_ELIF },
1834 { "else", 4, COND_ELSE },
1835 { "", 0, COND_NONE },
1836 };
1837 const struct cond_tbl_s *p;
1838
1839 for (p = cond_tbl; p->len; p++) {
1840 if (strncmp(l, p->name, p->len) == 0 &&
1841 isspace(CAST(unsigned char, l[p->len]))) {
1842 if (t)
1843 *t = l + p->len;
1844 break;
1845 }
1846 }
1847 return p->cond;
1848 }
1849
1850 file_private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1851 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1852 {
1853 int last_cond;
1854 last_cond = ms->c.li[cont_level].last_cond;
1855
1856 switch (cond) {
1857 case COND_IF:
1858 if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1859 if (ms->flags & MAGIC_CHECK)
1860 file_magwarn(ms, "syntax error: `if'");
1861 return -1;
1862 }
1863 last_cond = COND_IF;
1864 break;
1865
1866 case COND_ELIF:
1867 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1868 if (ms->flags & MAGIC_CHECK)
1869 file_magwarn(ms, "syntax error: `elif'");
1870 return -1;
1871 }
1872 last_cond = COND_ELIF;
1873 break;
1874
1875 case COND_ELSE:
1876 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1877 if (ms->flags & MAGIC_CHECK)
1878 file_magwarn(ms, "syntax error: `else'");
1879 return -1;
1880 }
1881 last_cond = COND_NONE;
1882 break;
1883
1884 case COND_NONE:
1885 last_cond = COND_NONE;
1886 break;
1887 }
1888
1889 ms->c.li[cont_level].last_cond = last_cond;
1890 return 0;
1891 }
1892 #endif /* ENABLE_CONDITIONALS */
1893
1894 file_private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1895 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1896 {
1897 const char *l = *lp;
1898
1899 while (!isspace(CAST(unsigned char, *++l)))
1900 switch (*l) {
1901 case CHAR_INDIRECT_RELATIVE:
1902 m->str_flags |= INDIRECT_RELATIVE;
1903 break;
1904 default:
1905 if (ms->flags & MAGIC_CHECK)
1906 file_magwarn(ms, "indirect modifier `%c' "
1907 "invalid", *l);
1908 *lp = l;
1909 return -1;
1910 }
1911 *lp = l;
1912 return 0;
1913 }
1914
1915 file_private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1916 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1917 int op)
1918 {
1919 const char *l = *lp;
1920 char *t;
1921 uint64_t val;
1922
1923 ++l;
1924 m->mask_op |= op;
1925 val = CAST(uint64_t, strtoull(l, &t, 0));
1926 l = t;
1927 m->num_mask = file_signextend(ms, m, val);
1928 eatsize(&l);
1929 *lp = l;
1930 }
1931
1932 file_private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1933 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1934 {
1935 const char *l = *lp;
1936 char *t;
1937 int have_range = 0;
1938
1939 while (!isspace(CAST(unsigned char, *++l))) {
1940 switch (*l) {
1941 case '0': case '1': case '2':
1942 case '3': case '4': case '5':
1943 case '6': case '7': case '8':
1944 case '9':
1945 if (have_range && (ms->flags & MAGIC_CHECK))
1946 file_magwarn(ms, "multiple ranges");
1947 have_range = 1;
1948 m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1949 if (m->str_range == 0)
1950 file_magwarn(ms, "zero range");
1951 l = t - 1;
1952 break;
1953 case CHAR_COMPACT_WHITESPACE:
1954 m->str_flags |= STRING_COMPACT_WHITESPACE;
1955 break;
1956 case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1957 m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1958 break;
1959 case CHAR_IGNORE_LOWERCASE:
1960 m->str_flags |= STRING_IGNORE_LOWERCASE;
1961 break;
1962 case CHAR_IGNORE_UPPERCASE:
1963 m->str_flags |= STRING_IGNORE_UPPERCASE;
1964 break;
1965 case CHAR_REGEX_OFFSET_START:
1966 m->str_flags |= REGEX_OFFSET_START;
1967 break;
1968 case CHAR_BINTEST:
1969 m->str_flags |= STRING_BINTEST;
1970 break;
1971 case CHAR_TEXTTEST:
1972 m->str_flags |= STRING_TEXTTEST;
1973 break;
1974 case CHAR_TRIM:
1975 m->str_flags |= STRING_TRIM;
1976 break;
1977 case CHAR_FULL_WORD:
1978 m->str_flags |= STRING_FULL_WORD;
1979 break;
1980 case CHAR_PSTRING_1_LE:
1981 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1982 if (m->type != FILE_PSTRING)
1983 goto bad;
1984 SET_LENGTH(PSTRING_1_LE);
1985 break;
1986 case CHAR_PSTRING_2_BE:
1987 if (m->type != FILE_PSTRING)
1988 goto bad;
1989 SET_LENGTH(PSTRING_2_BE);
1990 break;
1991 case CHAR_PSTRING_2_LE:
1992 if (m->type != FILE_PSTRING)
1993 goto bad;
1994 SET_LENGTH(PSTRING_2_LE);
1995 break;
1996 case CHAR_PSTRING_4_BE:
1997 if (m->type != FILE_PSTRING)
1998 goto bad;
1999 SET_LENGTH(PSTRING_4_BE);
2000 break;
2001 case CHAR_PSTRING_4_LE:
2002 switch (m->type) {
2003 case FILE_PSTRING:
2004 case FILE_REGEX:
2005 break;
2006 default:
2007 goto bad;
2008 }
2009 SET_LENGTH(PSTRING_4_LE);
2010 break;
2011 case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
2012 if (m->type != FILE_PSTRING)
2013 goto bad;
2014 m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
2015 break;
2016 default:
2017 bad:
2018 if (ms->flags & MAGIC_CHECK)
2019 file_magwarn(ms, "string modifier `%c' "
2020 "invalid", *l);
2021 goto out;
2022 }
2023 /* allow multiple '/' for readability */
2024 if (l[1] == '/' && !isspace(CAST(unsigned char, l[2])))
2025 l++;
2026 }
2027 if (string_modifier_check(ms, m) == -1)
2028 goto out;
2029 *lp = l;
2030 return 0;
2031 out:
2032 *lp = l;
2033 return -1;
2034 }
2035
2036 /*
2037 * parse one line from magic file, put into magic[index++] if valid
2038 */
2039 file_private int
parse(struct magic_set * ms,struct magic_entry * me,const char * file,const char * line,size_t llen,size_t lineno,int action)2040 parse(struct magic_set *ms, struct magic_entry *me, const char *file,
2041 const char *line, size_t llen, size_t lineno, int action)
2042 {
2043 #ifdef ENABLE_CONDITIONALS
2044 static uint32_t last_cont_level = 0;
2045 #endif
2046 size_t i;
2047 struct magic *m;
2048 const char *l = line, *el = line + llen;
2049 char *t;
2050 int op;
2051 uint32_t cont_level;
2052 int32_t diff;
2053
2054 cont_level = 0;
2055
2056 /*
2057 * Parse the offset.
2058 */
2059 while (*l == '>') {
2060 if (l >= el)
2061 return -1;
2062 ++l; /* step over */
2063 cont_level++;
2064 }
2065 #ifdef ENABLE_CONDITIONALS
2066 if (cont_level == 0 || cont_level > last_cont_level)
2067 if (file_check_mem(ms, cont_level) == -1)
2068 return -1;
2069 last_cont_level = cont_level;
2070 #endif
2071 if (cont_level != 0) {
2072 if (me->mp == NULL) {
2073 file_magerror(ms, "No current entry for continuation");
2074 return -1;
2075 }
2076 if (me->cont_count == 0) {
2077 file_magerror(ms, "Continuations present with 0 count");
2078 return -1;
2079 }
2080 m = &me->mp[me->cont_count - 1];
2081 diff = CAST(int32_t, cont_level) - CAST(int32_t, m->cont_level);
2082 if (diff > 1)
2083 file_magwarn(ms, "New continuation level %u is more "
2084 "than one larger than current level %u", cont_level,
2085 m->cont_level);
2086 if (me->cont_count == me->max_count) {
2087 struct magic *nm;
2088 size_t cnt = me->max_count + ALLOC_CHUNK;
2089 if ((nm = CAST(struct magic *, realloc(me->mp,
2090 sizeof(*nm) * cnt))) == NULL) {
2091 file_oomem(ms, sizeof(*nm) * cnt);
2092 return -1;
2093 }
2094 me->mp = nm;
2095 me->max_count = CAST(uint32_t, cnt);
2096 }
2097 m = &me->mp[me->cont_count++];
2098 (void)memset(m, 0, sizeof(*m));
2099 m->cont_level = cont_level;
2100 } else {
2101 static const size_t len = sizeof(*m) * ALLOC_CHUNK;
2102 if (me->mp != NULL)
2103 return 1;
2104 if ((m = CAST(struct magic *, malloc(len))) == NULL) {
2105 file_oomem(ms, len);
2106 return -1;
2107 }
2108 me->mp = m;
2109 me->max_count = ALLOC_CHUNK;
2110 (void)memset(m, 0, sizeof(*m));
2111 m->factor_op = FILE_FACTOR_OP_NONE;
2112 m->cont_level = 0;
2113 me->cont_count = 1;
2114 }
2115 m->lineno = CAST(uint32_t, lineno);
2116
2117 if (*l == '&') { /* m->cont_level == 0 checked below. */
2118 ++l; /* step over */
2119 m->flag |= OFFADD;
2120 }
2121 if (*l == '(') {
2122 ++l; /* step over */
2123 m->flag |= INDIR;
2124 if (m->flag & OFFADD)
2125 m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
2126
2127 if (*l == '&') { /* m->cont_level == 0 checked below */
2128 ++l; /* step over */
2129 m->flag |= OFFADD;
2130 }
2131 }
2132 /* Indirect offsets are not valid at level 0. */
2133 if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) {
2134 if (ms->flags & MAGIC_CHECK)
2135 file_magwarn(ms, "relative offset at level 0");
2136 return -1;
2137 }
2138
2139 /* get offset, then skip over it */
2140 if (*l == '-' || *l == '+') {
2141 ++l; /* step over */
2142 m->flag |= l[-1] == '-' ? OFFNEGATIVE : OFFPOSITIVE;
2143 }
2144 m->offset = CAST(int32_t, strtol(l, &t, 0));
2145 if (l == t) {
2146 if (ms->flags & MAGIC_CHECK)
2147 file_magwarn(ms, "offset `%s' invalid", l);
2148 return -1;
2149 }
2150
2151 l = t;
2152
2153 if (m->flag & INDIR) {
2154 m->in_type = FILE_LONG;
2155 m->in_offset = 0;
2156 m->in_op = 0;
2157 /*
2158 * read [.,lbs][+-]nnnnn)
2159 */
2160 if (*l == '.' || *l == ',') {
2161 if (*l == ',')
2162 m->in_op |= FILE_OPSIGNED;
2163 l++;
2164 switch (*l) {
2165 case 'l':
2166 m->in_type = FILE_LELONG;
2167 break;
2168 case 'L':
2169 m->in_type = FILE_BELONG;
2170 break;
2171 case 'm':
2172 m->in_type = FILE_MELONG;
2173 break;
2174 case 'h':
2175 case 's':
2176 m->in_type = FILE_LESHORT;
2177 break;
2178 case 'H':
2179 case 'S':
2180 m->in_type = FILE_BESHORT;
2181 break;
2182 case 'c':
2183 case 'b':
2184 case 'C':
2185 case 'B':
2186 m->in_type = FILE_BYTE;
2187 break;
2188 case 'e':
2189 case 'f':
2190 case 'g':
2191 m->in_type = FILE_LEDOUBLE;
2192 break;
2193 case 'E':
2194 case 'F':
2195 case 'G':
2196 m->in_type = FILE_BEDOUBLE;
2197 break;
2198 case 'i':
2199 m->in_type = FILE_LEID3;
2200 break;
2201 case 'I':
2202 m->in_type = FILE_BEID3;
2203 break;
2204 case 'o':
2205 m->in_type = FILE_OCTAL;
2206 break;
2207 case 'q':
2208 m->in_type = FILE_LEQUAD;
2209 break;
2210 case 'Q':
2211 m->in_type = FILE_BEQUAD;
2212 break;
2213 default:
2214 if (ms->flags & MAGIC_CHECK)
2215 file_magwarn(ms,
2216 "indirect offset type `%c' invalid",
2217 *l);
2218 return -1;
2219 }
2220 l++;
2221 }
2222
2223 if (*l == '~') {
2224 m->in_op |= FILE_OPINVERSE;
2225 l++;
2226 }
2227 if ((op = get_op(*l)) != -1) {
2228 m->in_op |= op;
2229 l++;
2230 }
2231 if (*l == '(') {
2232 m->in_op |= FILE_OPINDIRECT;
2233 l++;
2234 }
2235 if (isdigit(CAST(unsigned char, *l)) || *l == '-') {
2236 m->in_offset = CAST(int32_t, strtol(l, &t, 0));
2237 if (l == t) {
2238 if (ms->flags & MAGIC_CHECK)
2239 file_magwarn(ms,
2240 "in_offset `%s' invalid", l);
2241 return -1;
2242 }
2243 l = t;
2244 }
2245 if (*l++ != ')' ||
2246 ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) {
2247 if (ms->flags & MAGIC_CHECK)
2248 file_magwarn(ms,
2249 "missing ')' in indirect offset");
2250 return -1;
2251 }
2252 }
2253 EATAB;
2254
2255 #ifdef ENABLE_CONDITIONALS
2256 m->cond = get_cond(l, &l);
2257 if (check_cond(ms, m->cond, cont_level) == -1)
2258 return -1;
2259
2260 EATAB;
2261 #endif
2262
2263 /*
2264 * Parse the type.
2265 */
2266 if (*l == 'u') {
2267 /*
2268 * Try it as a keyword type prefixed by "u"; match what
2269 * follows the "u". If that fails, try it as an SUS
2270 * integer type.
2271 */
2272 m->type = get_type(type_tbl, l + 1, &l);
2273 if (m->type == FILE_INVALID) {
2274 /*
2275 * Not a keyword type; parse it as an SUS type,
2276 * 'u' possibly followed by a number or C/S/L.
2277 */
2278 m->type = get_standard_integer_type(l, &l);
2279 }
2280 /* It's unsigned. */
2281 if (m->type != FILE_INVALID)
2282 m->flag |= UNSIGNED;
2283 } else {
2284 /*
2285 * Try it as a keyword type. If that fails, try it as
2286 * an SUS integer type if it begins with "d" or as an
2287 * SUS string type if it begins with "s". In any case,
2288 * it's not unsigned.
2289 */
2290 m->type = get_type(type_tbl, l, &l);
2291 if (m->type == FILE_INVALID) {
2292 /*
2293 * Not a keyword type; parse it as an SUS type,
2294 * either 'd' possibly followed by a number or
2295 * C/S/L, or just 's'.
2296 */
2297 if (*l == 'd')
2298 m->type = get_standard_integer_type(l, &l);
2299 else if (*l == 's'
2300 && !isalpha(CAST(unsigned char, l[1]))) {
2301 m->type = FILE_STRING;
2302 ++l;
2303 }
2304 }
2305 }
2306
2307 if (m->type == FILE_INVALID) {
2308 /* Not found - try it as a special keyword. */
2309 m->type = get_type(special_tbl, l, &l);
2310 }
2311
2312 if (m->type == FILE_INVALID) {
2313 if (ms->flags & MAGIC_CHECK)
2314 file_magwarn(ms, "type `%s' invalid", l);
2315 return -1;
2316 }
2317
2318 if (m->type == FILE_NAME && cont_level != 0) {
2319 if (ms->flags & MAGIC_CHECK)
2320 file_magwarn(ms, "`name%s' entries can only be "
2321 "declared at top level", l);
2322 return -1;
2323 }
2324
2325 /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2326 /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2327
2328 m->mask_op = 0;
2329 if (*l == '~') {
2330 if (!IS_STRING(m->type))
2331 m->mask_op |= FILE_OPINVERSE;
2332 else if (ms->flags & MAGIC_CHECK)
2333 file_magwarn(ms, "'~' invalid for string types");
2334 ++l;
2335 }
2336 m->str_range = 0;
2337 m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2338 if ((op = get_op(*l)) != -1) {
2339 if (IS_STRING(m->type)) {
2340 int r;
2341
2342 if (op != FILE_OPDIVIDE) {
2343 if (ms->flags & MAGIC_CHECK)
2344 file_magwarn(ms,
2345 "invalid string/indirect op: "
2346 "`%c'", *t);
2347 return -1;
2348 }
2349
2350 if (m->type == FILE_INDIRECT)
2351 r = parse_indirect_modifier(ms, m, &l);
2352 else
2353 r = parse_string_modifier(ms, m, &l);
2354 if (r == -1)
2355 return -1;
2356 } else
2357 parse_op_modifier(ms, m, &l, op);
2358 }
2359
2360 /*
2361 * We used to set mask to all 1's here, instead let's just not do
2362 * anything if mask = 0 (unless you have a better idea)
2363 */
2364 EATAB;
2365
2366 switch (*l) {
2367 case '>':
2368 case '<':
2369 m->reln = *l;
2370 ++l;
2371 if (*l == '=') {
2372 if (ms->flags & MAGIC_CHECK) {
2373 file_magwarn(ms, "%c= not supported",
2374 m->reln);
2375 return -1;
2376 }
2377 ++l;
2378 }
2379 break;
2380 /* Old-style anding: "0 byte &0x80 dynamically linked" */
2381 case '&':
2382 case '^':
2383 case '=':
2384 m->reln = *l;
2385 ++l;
2386 if (*l == '=') {
2387 /* HP compat: ignore &= etc. */
2388 ++l;
2389 }
2390 break;
2391 case '!':
2392 m->reln = *l;
2393 ++l;
2394 break;
2395 default:
2396 m->reln = '='; /* the default relation */
2397 if (*l == 'x' && ((isascii(CAST(unsigned char, l[1])) &&
2398 isspace(CAST(unsigned char, l[1]))) || !l[1])) {
2399 m->reln = *l;
2400 ++l;
2401 }
2402 break;
2403 }
2404
2405
2406 /*
2407 * Grab the value part, except for an 'x' reln.
2408 */
2409 if (m->reln != 'x') {
2410 if (*l == '\0') {
2411 file_magwarn(ms, "incomplete magic `%s'", line);
2412 return -1;
2413 }
2414 if (getvalue(ms, m, &l, action))
2415 return -1;
2416 }
2417
2418 /*
2419 * TODO finish this macro and start using it!
2420 * #define offsetcheck {if (offset > ms->bytes_max -1)
2421 * magwarn("offset too big"); }
2422 */
2423
2424 /*
2425 * Now get last part - the description
2426 */
2427 EATAB;
2428 if (l[0] == '\b') {
2429 ++l;
2430 m->flag |= NOSPACE;
2431 } else if ((l[0] == '\\') && (l[1] == 'b')) {
2432 ++l;
2433 ++l;
2434 m->flag |= NOSPACE;
2435 }
2436 for (i = 0; i < sizeof(m->desc) && (m->desc[i++] = *l++) != '\0';)
2437 continue;
2438 if (m->desc[0] == '\0') {
2439 // Tuck in the filename for debugging.
2440 strlcpy(m->desc + 1, file, sizeof(m->desc) - 1);
2441 }
2442 if (i == sizeof(m->desc)) {
2443 m->desc[sizeof(m->desc) - 1] = '\0';
2444 if (ms->flags & MAGIC_CHECK)
2445 file_magwarn(ms, "description `%s' truncated", m->desc);
2446 }
2447
2448 /*
2449 * We only do this check while compiling, or if any of the magic
2450 * files were not compiled.
2451 */
2452 if (ms->flags & MAGIC_CHECK) {
2453 if (check_format(ms, m) == -1)
2454 return -1;
2455 }
2456 #ifndef COMPILE_ONLY
2457 if (action == FILE_CHECK) {
2458 file_mdump(m);
2459 }
2460 #endif
2461 m->mimetype[0] = '\0'; /* initialise MIME type to none */
2462 return 0;
2463 }
2464
2465 /*
2466 * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2467 * if valid
2468 */
2469 /*ARGSUSED*/
2470 file_private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2471 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line,
2472 size_t len __attribute__((__unused__)))
2473 {
2474 const char *l = line;
2475 char *el;
2476 unsigned long factor;
2477 char sbuf[512];
2478 struct magic *m = &me->mp[0];
2479
2480 if (m->factor_op != FILE_FACTOR_OP_NONE) {
2481 file_magwarn(ms,
2482 "Current entry already has a strength type: %c %d",
2483 m->factor_op, m->factor);
2484 return -1;
2485 }
2486 if (m->type == FILE_NAME) {
2487 file_magwarn(ms, "%s: Strength setting is not supported in "
2488 "\"name\" magic entries",
2489 file_printable(ms, sbuf, sizeof(sbuf), m->value.s,
2490 sizeof(m->value.s)));
2491 return -1;
2492 }
2493 EATAB;
2494 switch (*l) {
2495 case FILE_FACTOR_OP_NONE:
2496 break;
2497 case FILE_FACTOR_OP_PLUS:
2498 case FILE_FACTOR_OP_MINUS:
2499 case FILE_FACTOR_OP_TIMES:
2500 case FILE_FACTOR_OP_DIV:
2501 m->factor_op = *l++;
2502 break;
2503 default:
2504 file_magwarn(ms, "Unknown factor op `%c'", *l);
2505 return -1;
2506 }
2507 EATAB;
2508 factor = strtoul(l, &el, 0);
2509 if (factor > 255) {
2510 file_magwarn(ms, "Too large factor `%lu'", factor);
2511 goto out;
2512 }
2513 if (*el && !isspace(CAST(unsigned char, *el))) {
2514 file_magwarn(ms, "Bad factor `%s'", l);
2515 goto out;
2516 }
2517 m->factor = CAST(uint8_t, factor);
2518 if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2519 file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2520 m->factor_op, m->factor);
2521 goto out;
2522 }
2523 return 0;
2524 out:
2525 m->factor_op = FILE_FACTOR_OP_NONE;
2526 m->factor = 0;
2527 return -1;
2528 }
2529
2530 file_private int
goodchar(unsigned char x,const char * extra)2531 goodchar(unsigned char x, const char *extra)
2532 {
2533 return (isascii(x) && isalnum(x)) || strchr(extra, x);
2534 }
2535
2536 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)2537 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2538 size_t llen, off_t off, size_t len, const char *name, const char *extra,
2539 int nt)
2540 {
2541 size_t i;
2542 const char *l = line;
2543 struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2544 char *buf = CAST(char *, CAST(void *, m)) + off;
2545
2546 if (buf[0] != '\0') {
2547 len = nt ? strlen(buf) : len;
2548 file_magwarn(ms, "Current entry already has a %s type "
2549 "`%.*s', new type `%s'", name, CAST(int, len), buf, l);
2550 return -1;
2551 }
2552
2553 if (*m->desc == '\0') {
2554 file_magwarn(ms, "Current entry does not yet have a "
2555 "description for adding a %s type", name);
2556 return -1;
2557 }
2558
2559 EATAB;
2560 for (i = 0; *l && i < llen && i < len && goodchar(*l, extra);
2561 buf[i++] = *l++)
2562 continue;
2563
2564 if (i == len && *l) {
2565 if (nt)
2566 buf[len - 1] = '\0';
2567 if (ms->flags & MAGIC_CHECK)
2568 file_magwarn(ms, "%s type `%s' truncated %"
2569 SIZE_T_FORMAT "u", name, line, i);
2570 } else {
2571 if (!isspace(CAST(unsigned char, *l)) && !goodchar(*l, extra))
2572 file_magwarn(ms, "%s type `%s' has bad char '%c'",
2573 name, line, *l);
2574 if (nt)
2575 buf[i] = '\0';
2576 }
2577
2578 if (i > 0)
2579 return 0;
2580
2581 file_magerror(ms, "Bad magic entry '%s'", line);
2582 return -1;
2583 }
2584
2585 /*
2586 * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2587 * magic[index - 1]
2588 */
2589 file_private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2590 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line,
2591 size_t len)
2592 {
2593 return parse_extra(ms, me, line, len,
2594 CAST(off_t, offsetof(struct magic, apple)),
2595 sizeof(me->mp[me->cont_count - 1].apple), "APPLE", "!+-./?", 0);
2596 }
2597
2598 /*
2599 * Parse a comma-separated list of extensions
2600 */
2601 file_private int
parse_ext(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2602 parse_ext(struct magic_set *ms, struct magic_entry *me, const char *line,
2603 size_t len)
2604 {
2605 return parse_extra(ms, me, line, len,
2606 CAST(off_t, offsetof(struct magic, ext)),
2607 sizeof(me->mp[me->cont_count - 1].ext), "EXTENSION", ",!+-/@?_$&~.",
2608 0);
2609 /* & for b&w */
2610 /* ~ for journal~ */
2611 }
2612
2613 /*
2614 * parse a MIME annotation line from magic file, put into magic[index - 1]
2615 * if valid
2616 */
2617 file_private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2618 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line,
2619 size_t len)
2620 {
2621 return parse_extra(ms, me, line, len,
2622 CAST(off_t, offsetof(struct magic, mimetype)),
2623 sizeof(me->mp[me->cont_count - 1].mimetype), "MIME", "+-/.$?:{};=",
2624 1);
2625 }
2626
2627 file_private int
check_format_type(const char * ptr,int type,const char ** estr)2628 check_format_type(const char *ptr, int type, const char **estr)
2629 {
2630 int quad = 0, h;
2631 size_t len, cnt;
2632 if (*ptr == '\0') {
2633 /* Missing format string; bad */
2634 *estr = "missing format spec";
2635 return -1;
2636 }
2637
2638 switch (file_formats[type]) {
2639 case FILE_FMT_QUAD:
2640 quad = 1;
2641 /*FALLTHROUGH*/
2642 case FILE_FMT_NUM:
2643 if (quad == 0) {
2644 switch (type) {
2645 case FILE_BYTE:
2646 h = 2;
2647 break;
2648 case FILE_SHORT:
2649 case FILE_BESHORT:
2650 case FILE_LESHORT:
2651 h = 1;
2652 break;
2653 case FILE_LONG:
2654 case FILE_BELONG:
2655 case FILE_LELONG:
2656 case FILE_MELONG:
2657 case FILE_LEID3:
2658 case FILE_BEID3:
2659 case FILE_INDIRECT:
2660 h = 0;
2661 break;
2662 default:
2663 fprintf(stderr, "Bad number format %d", type);
2664 abort();
2665 }
2666 } else
2667 h = 0;
2668 while (*ptr && strchr("+-.#", *ptr) != NULL)
2669 ptr++;
2670 #define CHECKLEN() do { \
2671 for (len = cnt = 0; isdigit(CAST(unsigned char, *ptr)); ptr++, cnt++) \
2672 len = len * 10 + (*ptr - '0'); \
2673 if (cnt > 5 || len > 1024) \
2674 goto toolong; \
2675 } while (/*CONSTCOND*/0)
2676
2677 CHECKLEN();
2678 if (*ptr == '.')
2679 ptr++;
2680 CHECKLEN();
2681 if (quad) {
2682 if (*ptr++ != 'l')
2683 goto invalid;
2684 if (*ptr++ != 'l')
2685 goto invalid;
2686 }
2687
2688 switch (*ptr++) {
2689 #ifdef STRICT_FORMAT /* "long" formats are int formats for us */
2690 /* so don't accept the 'l' modifier */
2691 case 'l':
2692 switch (*ptr++) {
2693 case 'i':
2694 case 'd':
2695 case 'u':
2696 case 'o':
2697 case 'x':
2698 case 'X':
2699 if (h == 0)
2700 return 0;
2701 /*FALLTHROUGH*/
2702 default:
2703 goto invalid;
2704 }
2705
2706 /*
2707 * Don't accept h and hh modifiers. They make writing
2708 * magic entries more complicated, for very little benefit
2709 */
2710 case 'h':
2711 if (h-- <= 0)
2712 goto invalid;
2713 switch (*ptr++) {
2714 case 'h':
2715 if (h-- <= 0)
2716 goto invalid;
2717 switch (*ptr++) {
2718 case 'i':
2719 case 'd':
2720 case 'u':
2721 case 'o':
2722 case 'x':
2723 case 'X':
2724 return 0;
2725 default:
2726 goto invalid;
2727 }
2728 case 'i':
2729 case 'd':
2730 case 'u':
2731 case 'o':
2732 case 'x':
2733 case 'X':
2734 if (h == 0)
2735 return 0;
2736 /*FALLTHROUGH*/
2737 default:
2738 goto invalid;
2739 }
2740 #endif
2741 case 'c':
2742 if (h == 2)
2743 return 0;
2744 goto invalid;
2745 case 'i':
2746 case 'd':
2747 case 'u':
2748 case 'o':
2749 case 'x':
2750 case 'X':
2751 #ifdef STRICT_FORMAT
2752 if (h == 0)
2753 return 0;
2754 /*FALLTHROUGH*/
2755 #else
2756 return 0;
2757 #endif
2758 default:
2759 goto invalid;
2760 }
2761
2762 case FILE_FMT_FLOAT:
2763 case FILE_FMT_DOUBLE:
2764 if (*ptr == '-')
2765 ptr++;
2766 if (*ptr == '.')
2767 ptr++;
2768 CHECKLEN();
2769 if (*ptr == '.')
2770 ptr++;
2771 CHECKLEN();
2772 switch (*ptr++) {
2773 case 'e':
2774 case 'E':
2775 case 'f':
2776 case 'F':
2777 case 'g':
2778 case 'G':
2779 return 0;
2780
2781 default:
2782 goto invalid;
2783 }
2784
2785
2786 case FILE_FMT_STR:
2787 if (*ptr == '-')
2788 ptr++;
2789 while (isdigit(CAST(unsigned char, *ptr)))
2790 ptr++;
2791 if (*ptr == '.') {
2792 ptr++;
2793 while (isdigit(CAST(unsigned char , *ptr)))
2794 ptr++;
2795 }
2796
2797 switch (*ptr++) {
2798 case 's':
2799 return 0;
2800 default:
2801 goto invalid;
2802 }
2803
2804 default:
2805 /* internal error */
2806 fprintf(stderr, "Bad file format %d", type);
2807 abort();
2808 }
2809 invalid:
2810 *estr = "not valid";
2811 return -1;
2812 toolong:
2813 *estr = "too long";
2814 return -1;
2815 }
2816
2817 /*
2818 * Check that the optional printf format in description matches
2819 * the type of the magic.
2820 */
2821 file_private int
check_format(struct magic_set * ms,struct magic * m)2822 check_format(struct magic_set *ms, struct magic *m)
2823 {
2824 char *ptr;
2825 const char *estr;
2826
2827 for (ptr = m->desc; *ptr; ptr++)
2828 if (*ptr == '%')
2829 break;
2830 if (*ptr == '\0') {
2831 /* No format string; ok */
2832 return 1;
2833 }
2834
2835 assert(file_nformats == file_nnames);
2836
2837 if (m->type >= file_nformats) {
2838 file_magwarn(ms, "Internal error inconsistency between "
2839 "m->type and format strings");
2840 return -1;
2841 }
2842 if (file_formats[m->type] == FILE_FMT_NONE) {
2843 file_magwarn(ms, "No format string for `%s' with description "
2844 "`%s'", m->desc, file_names[m->type]);
2845 return -1;
2846 }
2847
2848 ptr++;
2849 if (check_format_type(ptr, m->type, &estr) == -1) {
2850 /*
2851 * TODO: this error message is unhelpful if the format
2852 * string is not one character long
2853 */
2854 file_magwarn(ms, "Printf format is %s for type "
2855 "`%s' in description `%s'", estr,
2856 file_names[m->type], m->desc);
2857 return -1;
2858 }
2859
2860 for (; *ptr; ptr++) {
2861 if (*ptr == '%') {
2862 file_magwarn(ms,
2863 "Too many format strings (should have at most one) "
2864 "for `%s' with description `%s'",
2865 file_names[m->type], m->desc);
2866 return -1;
2867 }
2868 }
2869 return 0;
2870 }
2871
2872 /*
2873 * Read a numeric value from a pointer, into the value union of a magic
2874 * pointer, according to the magic type. Update the string pointer to point
2875 * just after the number read. Return 0 for success, non-zero for failure.
2876 */
2877 file_no_overflow file_private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2878 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2879 {
2880 char *ep;
2881 uint64_t ull;
2882 int y;
2883
2884 switch (m->type) {
2885 case FILE_BESTRING16:
2886 case FILE_LESTRING16:
2887 case FILE_STRING:
2888 case FILE_PSTRING:
2889 case FILE_REGEX:
2890 case FILE_SEARCH:
2891 case FILE_NAME:
2892 case FILE_USE:
2893 case FILE_DER:
2894 case FILE_OCTAL:
2895 *p = getstr(ms, m, *p, action == FILE_COMPILE);
2896 if (*p == NULL) {
2897 if (ms->flags & MAGIC_CHECK)
2898 file_magwarn(ms, "cannot get string from `%s'",
2899 m->value.s);
2900 return -1;
2901 }
2902 if (m->type == FILE_REGEX) {
2903 file_regex_t rx;
2904 int rc = file_regcomp(ms, &rx, m->value.s,
2905 REG_EXTENDED | REGEX_ICASE(m));
2906 if (rc == 0) {
2907 file_regfree(&rx);
2908 }
2909 return rc ? -1 : 0;
2910 }
2911 return 0;
2912 default:
2913 if (m->reln == 'x')
2914 return 0;
2915 break;
2916 }
2917
2918 switch (m->type) {
2919 case FILE_FLOAT:
2920 case FILE_BEFLOAT:
2921 case FILE_LEFLOAT:
2922 errno = 0;
2923 #ifdef HAVE_STRTOF
2924 m->value.f = strtof(*p, &ep);
2925 #else
2926 m->value.f = (float)strtod(*p, &ep);
2927 #endif
2928 if (errno == 0)
2929 *p = ep;
2930 return 0;
2931 case FILE_DOUBLE:
2932 case FILE_BEDOUBLE:
2933 case FILE_LEDOUBLE:
2934 errno = 0;
2935 m->value.d = strtod(*p, &ep);
2936 if (errno == 0)
2937 *p = ep;
2938 return 0;
2939 case FILE_BEGUID:
2940 case FILE_LEGUID:
2941 case FILE_GUID:
2942 if (file_parse_guid(*p, m->value.guid) == -1) {
2943 file_magwarn(ms, "Error parsing guid `%s'", *p);
2944 return -1;
2945 }
2946 *p += FILE_GUID_SIZE - 1;
2947 return 0;
2948 default:
2949 errno = 0;
2950 ull = CAST(uint64_t, strtoull(*p, &ep, 0));
2951 m->value.q = file_signextend(ms, m, ull);
2952 if (*p == ep) {
2953 file_magwarn(ms, "Unparsable number `%s'", *p);
2954 return -1;
2955 } else {
2956 size_t ts = typesize(m->type);
2957 uint64_t x;
2958 const char *q;
2959
2960 if (ts == FILE_BADSIZE) {
2961 file_magwarn(ms,
2962 "Expected numeric type got `%s'",
2963 type_tbl[m->type].name);
2964 return -1;
2965 }
2966 for (q = *p; isspace(CAST(unsigned char, *q)); q++)
2967 continue;
2968 if (*q == '-' && ull != UINT64_MAX)
2969 ull = -CAST(int64_t, ull);
2970 switch (ts) {
2971 case 1:
2972 x = CAST(uint64_t, ull & ~0xffULL);
2973 y = (x & ~0xffULL) != ~0xffULL;
2974 break;
2975 case 2:
2976 x = CAST(uint64_t, ull & ~0xffffULL);
2977 y = (x & ~0xffffULL) != ~0xffffULL;
2978 break;
2979 case 4:
2980 x = CAST(uint64_t, ull & ~0xffffffffULL);
2981 y = (x & ~0xffffffffULL) != ~0xffffffffULL;
2982 break;
2983 case 8:
2984 x = 0;
2985 y = 0;
2986 break;
2987 default:
2988 fprintf(stderr, "Bad width %zu", ts);
2989 abort();
2990 }
2991 if (x && y) {
2992 file_magwarn(ms, "Overflow for numeric"
2993 " type `%s' value %#" PRIx64,
2994 type_tbl[m->type].name, ull);
2995 return -1;
2996 }
2997 }
2998 if (errno == 0) {
2999 *p = ep;
3000 eatsize(p);
3001 }
3002 return 0;
3003 }
3004 }
3005
3006 /*
3007 * Convert a string containing C character escapes. Stop at an unescaped
3008 * space or tab.
3009 * Copy the converted version to "m->value.s", and the length in m->vallen.
3010 * Return updated scan pointer as function result. Warn if set.
3011 */
3012 file_private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)3013 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
3014 {
3015 const char *origs = s;
3016 char *p = m->value.s;
3017 size_t plen = sizeof(m->value.s);
3018 char *origp = p;
3019 char *pmax = p + plen - 1;
3020 int c;
3021 int val;
3022 size_t bracket_nesting = 0;
3023
3024 while ((c = *s++) != '\0') {
3025 if (isspace(CAST(unsigned char, c)))
3026 break;
3027 if (p >= pmax) {
3028 file_error(ms, 0, "string too long: `%s'", origs);
3029 return NULL;
3030 }
3031 if (c != '\\') {
3032 if (c == '[') {
3033 bracket_nesting++;
3034 }
3035 if (c == ']' && bracket_nesting > 0) {
3036 bracket_nesting--;
3037 }
3038 *p++ = CAST(char, c);
3039 continue;
3040 }
3041 switch(c = *s++) {
3042
3043 case '\0':
3044 if (warn)
3045 file_magwarn(ms, "incomplete escape");
3046 s--;
3047 goto out;
3048 case '.':
3049 if (m->type == FILE_REGEX &&
3050 bracket_nesting == 0 && warn) {
3051 file_magwarn(ms, "escaped dot ('.') found, "
3052 "use \\\\. instead");
3053 }
3054 warn = 0; /* already did */
3055 /*FALLTHROUGH*/
3056 case '\t':
3057 if (warn) {
3058 file_magwarn(ms,
3059 "escaped tab found, use \\\\t instead");
3060 warn = 0; /* already did */
3061 }
3062 /*FALLTHROUGH*/
3063 default:
3064 if (warn) {
3065 if (isprint(CAST(unsigned char, c))) {
3066 /* Allow escaping of
3067 * ``relations'' */
3068 if (strchr("<>&^=!", c) == NULL
3069 && (m->type != FILE_REGEX ||
3070 strchr("[]().*?^$|{}", c)
3071 == NULL)) {
3072 file_magwarn(ms, "no "
3073 "need to escape "
3074 "`%c'", c);
3075 }
3076 } else {
3077 file_magwarn(ms,
3078 "unknown escape sequence: "
3079 "\\%03o", c);
3080 }
3081 }
3082 /*FALLTHROUGH*/
3083 /* space, perhaps force people to use \040? */
3084 case ' ':
3085 #if 0
3086 /*
3087 * Other things people escape, but shouldn't need to,
3088 * so we disallow them
3089 */
3090 case '\'':
3091 case '"':
3092 case '?':
3093 #endif
3094 /* Relations */
3095 case '>':
3096 case '<':
3097 case '&':
3098 case '^':
3099 case '=':
3100 case '!':
3101 /* and backslash itself */
3102 case '\\':
3103 *p++ = CAST(char, c);
3104 break;
3105
3106 case 'a':
3107 *p++ = '\a';
3108 break;
3109
3110 case 'b':
3111 *p++ = '\b';
3112 break;
3113
3114 case 'f':
3115 *p++ = '\f';
3116 break;
3117
3118 case 'n':
3119 *p++ = '\n';
3120 break;
3121
3122 case 'r':
3123 *p++ = '\r';
3124 break;
3125
3126 case 't':
3127 *p++ = '\t';
3128 break;
3129
3130 case 'v':
3131 *p++ = '\v';
3132 break;
3133
3134 /* \ and up to 3 octal digits */
3135 case '0':
3136 case '1':
3137 case '2':
3138 case '3':
3139 case '4':
3140 case '5':
3141 case '6':
3142 case '7':
3143 val = c - '0';
3144 c = *s++; /* try for 2 */
3145 if (c >= '0' && c <= '7') {
3146 val = (val << 3) | (c - '0');
3147 c = *s++; /* try for 3 */
3148 if (c >= '0' && c <= '7')
3149 val = (val << 3) | (c-'0');
3150 else
3151 --s;
3152 }
3153 else
3154 --s;
3155 *p++ = CAST(char, val);
3156 break;
3157
3158 /* \x and up to 2 hex digits */
3159 case 'x':
3160 val = 'x'; /* Default if no digits */
3161 c = hextoint(*s++); /* Get next char */
3162 if (c >= 0) {
3163 val = c;
3164 c = hextoint(*s++);
3165 if (c >= 0)
3166 val = (val << 4) + c;
3167 else
3168 --s;
3169 } else
3170 --s;
3171 *p++ = CAST(char, val);
3172 break;
3173 }
3174 }
3175 --s;
3176 out:
3177 *p = '\0';
3178 if (CAST(size_t, (p - origp)) > sizeof(m->value.s))
3179 return NULL;
3180 m->vallen = CAST(unsigned char, (p - origp));
3181 if (m->type == FILE_PSTRING) {
3182 size_t l = file_pstring_length_size(ms, m);
3183 if (l == FILE_BADSIZE)
3184 return NULL;
3185 if (m->vallen + l > sizeof(m->value.s))
3186 return NULL;
3187 m->vallen += CAST(unsigned char, l);
3188 }
3189 return s;
3190 }
3191
3192
3193 /* Single hex char to int; -1 if not a hex char. */
3194 file_private int
hextoint(int c)3195 hextoint(int c)
3196 {
3197 if (!isascii(CAST(unsigned char, c)))
3198 return -1;
3199 if (isdigit(CAST(unsigned char, c)))
3200 return c - '0';
3201 if ((c >= 'a') && (c <= 'f'))
3202 return c + 10 - 'a';
3203 if (( c>= 'A') && (c <= 'F'))
3204 return c + 10 - 'A';
3205 return -1;
3206 }
3207
3208
3209 /*
3210 * Print a string containing C character escapes.
3211 */
3212 file_protected void
file_showstr(FILE * fp,const char * s,size_t len)3213 file_showstr(FILE *fp, const char *s, size_t len)
3214 {
3215 char c;
3216
3217 for (;;) {
3218 if (len == FILE_BADSIZE) {
3219 c = *s++;
3220 if (c == '\0')
3221 break;
3222 }
3223 else {
3224 if (len-- == 0)
3225 break;
3226 c = *s++;
3227 }
3228 if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */
3229 (void) fputc(c, fp);
3230 else {
3231 (void) fputc('\\', fp);
3232 switch (c) {
3233 case '\a':
3234 (void) fputc('a', fp);
3235 break;
3236
3237 case '\b':
3238 (void) fputc('b', fp);
3239 break;
3240
3241 case '\f':
3242 (void) fputc('f', fp);
3243 break;
3244
3245 case '\n':
3246 (void) fputc('n', fp);
3247 break;
3248
3249 case '\r':
3250 (void) fputc('r', fp);
3251 break;
3252
3253 case '\t':
3254 (void) fputc('t', fp);
3255 break;
3256
3257 case '\v':
3258 (void) fputc('v', fp);
3259 break;
3260
3261 default:
3262 (void) fprintf(fp, "%.3o", c & 0377);
3263 break;
3264 }
3265 }
3266 }
3267 }
3268
3269 /*
3270 * eatsize(): Eat the size spec from a number [eg. 10UL]
3271 */
3272 file_private void
eatsize(const char ** p)3273 eatsize(const char **p)
3274 {
3275 const char *l = *p;
3276
3277 if (LOWCASE(*l) == 'u')
3278 l++;
3279
3280 switch (LOWCASE(*l)) {
3281 case 'l': /* long */
3282 case 's': /* short */
3283 case 'h': /* short */
3284 case 'b': /* char/byte */
3285 case 'c': /* char/byte */
3286 l++;
3287 /*FALLTHROUGH*/
3288 default:
3289 break;
3290 }
3291
3292 *p = l;
3293 }
3294
3295 /*
3296 * handle a buffer containing a compiled file.
3297 */
3298 file_private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)3299 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
3300 {
3301 struct magic_map *map;
3302
3303 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3304 file_oomem(ms, sizeof(*map));
3305 return NULL;
3306 }
3307 map->len = len;
3308 map->p = buf;
3309 map->type = MAP_TYPE_USER;
3310 if (check_buffer(ms, map, "buffer") != 0) {
3311 apprentice_unmap(map);
3312 return NULL;
3313 }
3314 return map;
3315 }
3316
3317 /*
3318 * handle a compiled file.
3319 */
3320
3321 file_private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)3322 apprentice_map(struct magic_set *ms, const char *fn)
3323 {
3324 int fd;
3325 struct stat st;
3326 char *dbname = NULL;
3327 struct magic_map *map;
3328 struct magic_map *rv = NULL;
3329
3330 fd = -1;
3331 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3332 file_oomem(ms, sizeof(*map));
3333 goto error;
3334 }
3335 map->type = MAP_TYPE_USER; /* unspecified */
3336
3337 dbname = mkdbname(ms, fn, 0);
3338 if (dbname == NULL)
3339 goto error;
3340
3341 if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
3342 goto error;
3343
3344 if (fstat(fd, &st) == -1) {
3345 file_error(ms, errno, "cannot stat `%s'", dbname);
3346 goto error;
3347 }
3348 if (st.st_size < 8 || st.st_size > maxoff_t()) {
3349 file_error(ms, 0, "file `%s' is too %s", dbname,
3350 st.st_size < 8 ? "small" : "large");
3351 goto error;
3352 }
3353
3354 map->len = CAST(size_t, st.st_size);
3355 #ifdef QUICK
3356 map->type = MAP_TYPE_MMAP;
3357 if ((map->p = mmap(0, CAST(size_t, st.st_size), PROT_READ|PROT_WRITE,
3358 MAP_PRIVATE|MAP_FILE, fd, CAST(off_t, 0))) == MAP_FAILED) {
3359 file_error(ms, errno, "cannot map `%s'", dbname);
3360 goto error;
3361 }
3362 #else
3363 map->type = MAP_TYPE_MALLOC;
3364 if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
3365 file_oomem(ms, map->len);
3366 goto error;
3367 }
3368 if (read(fd, map->p, map->len) != (ssize_t)map->len) {
3369 file_badread(ms);
3370 goto error;
3371 }
3372 #endif
3373 (void)close(fd);
3374 fd = -1;
3375
3376 if (check_buffer(ms, map, dbname) != 0) {
3377 goto error;
3378 }
3379 #ifdef QUICK
3380 if (mprotect(map->p, CAST(size_t, st.st_size), PROT_READ) == -1) {
3381 file_error(ms, errno, "cannot mprotect `%s'", dbname);
3382 goto error;
3383 }
3384 #endif
3385
3386 free(dbname);
3387 return map;
3388
3389 error:
3390 if (fd != -1)
3391 (void)close(fd);
3392 apprentice_unmap(map);
3393 free(dbname);
3394 return rv;
3395 }
3396
3397 file_private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)3398 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
3399 {
3400 uint32_t *ptr;
3401 uint32_t entries, nentries;
3402 uint32_t version;
3403 int i, needsbyteswap;
3404
3405 entries = CAST(uint32_t, map->len / sizeof(struct magic));
3406 if (entries < MAGIC_SETS) {
3407 file_error(ms, 0, "Too few magic entries %u in `%s'",
3408 entries, dbname);
3409 return -1;
3410 }
3411 if ((entries * sizeof(struct magic)) != map->len) {
3412 file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
3413 "a multiple of %" SIZE_T_FORMAT "u",
3414 dbname, map->len, sizeof(struct magic));
3415 return -1;
3416 }
3417
3418 ptr = CAST(uint32_t *, map->p);
3419 if (*ptr != MAGICNO) {
3420 if (file_swap4(*ptr) != MAGICNO) {
3421 file_error(ms, 0, "bad magic in `%s'", dbname);
3422 return -1;
3423 }
3424 needsbyteswap = 1;
3425 } else
3426 needsbyteswap = 0;
3427 if (needsbyteswap)
3428 version = file_swap4(ptr[1]);
3429 else
3430 version = ptr[1];
3431 if (version != VERSIONNO) {
3432 file_error(ms, 0, "File %s supports only version %d magic "
3433 "files. `%s' is version %d", VERSION,
3434 VERSIONNO, dbname, version);
3435 return -1;
3436 }
3437 map->magic[0] = CAST(struct magic *, map->p) + 1;
3438 nentries = 0;
3439 for (i = 0; i < MAGIC_SETS; i++) {
3440 if (needsbyteswap)
3441 map->nmagic[i] = file_swap4(ptr[i + 2]);
3442 else
3443 map->nmagic[i] = ptr[i + 2];
3444 if (map->nmagic[i] > entries) {
3445 file_error(ms, 0, "nmagic[%u] too large in `%s'", i,
3446 dbname);
3447 return -1;
3448 }
3449 if (i != MAGIC_SETS - 1)
3450 map->magic[i + 1] = map->magic[i] + map->nmagic[i];
3451 nentries += map->nmagic[i];
3452 }
3453 if (entries != nentries + 1) {
3454 file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
3455 dbname, entries, nentries + 1);
3456 return -1;
3457 }
3458 if (needsbyteswap)
3459 for (i = 0; i < MAGIC_SETS; i++)
3460 byteswap(map->magic[i], map->nmagic[i]);
3461 return 0;
3462 }
3463
3464 /*
3465 * handle an mmaped file.
3466 */
3467 file_private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)3468 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
3469 {
3470 static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
3471 static const size_t m = sizeof(**map->magic);
3472 int fd = -1;
3473 size_t len;
3474 char *dbname;
3475 int rv = -1;
3476 uint32_t i;
3477 union {
3478 struct magic m;
3479 uint32_t h[2 + MAGIC_SETS];
3480 } hdr;
3481
3482 dbname = mkdbname(ms, fn, 1);
3483
3484 if (dbname == NULL)
3485 goto out;
3486
3487 if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
3488 {
3489 file_error(ms, errno, "cannot open `%s'", dbname);
3490 goto out;
3491 }
3492 memset(&hdr, 0, sizeof(hdr));
3493 hdr.h[0] = MAGICNO;
3494 hdr.h[1] = VERSIONNO;
3495 memcpy(hdr.h + 2, map->nmagic, nm);
3496
3497 if (write(fd, &hdr, sizeof(hdr)) != CAST(ssize_t, sizeof(hdr))) {
3498 file_error(ms, errno, "error writing `%s'", dbname);
3499 goto out2;
3500 }
3501
3502 for (i = 0; i < MAGIC_SETS; i++) {
3503 len = m * map->nmagic[i];
3504 if (write(fd, map->magic[i], len) != CAST(ssize_t, len)) {
3505 file_error(ms, errno, "error writing `%s'", dbname);
3506 goto out2;
3507 }
3508 }
3509
3510 rv = 0;
3511 out2:
3512 if (fd != -1)
3513 (void)close(fd);
3514 out:
3515 apprentice_unmap(map);
3516 free(dbname);
3517 return rv;
3518 }
3519
3520 file_private const char ext[] = ".mgc";
3521 /*
3522 * make a dbname
3523 */
3524 file_private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3525 mkdbname(struct magic_set *ms, const char *fn, int strip)
3526 {
3527 const char *p, *q;
3528 char *buf;
3529
3530 if (strip) {
3531 if ((p = strrchr(fn, '/')) != NULL)
3532 fn = ++p;
3533 }
3534
3535 for (q = fn; *q; q++)
3536 continue;
3537 /* Look for .mgc */
3538 for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3539 if (*p != *q)
3540 break;
3541
3542 /* Did not find .mgc, restore q */
3543 if (p >= ext)
3544 for (q = fn; *q; q++)
3545 continue;
3546
3547 q++;
3548 /* Compatibility with old code that looked in .mime */
3549 if (ms->flags & MAGIC_MIME) {
3550 if (asprintf(&buf, "%.*s.mime%s", CAST(int, q - fn), fn, ext)
3551 < 0)
3552 return NULL;
3553 if (access(buf, R_OK) != -1) {
3554 ms->flags &= MAGIC_MIME_TYPE;
3555 return buf;
3556 }
3557 free(buf);
3558 }
3559 if (asprintf(&buf, "%.*s%s", CAST(int, q - fn), fn, ext) < 0)
3560 return NULL;
3561
3562 /* Compatibility with old code that looked in .mime */
3563 if (strstr(fn, ".mime") != NULL)
3564 ms->flags &= MAGIC_MIME_TYPE;
3565 return buf;
3566 }
3567
3568 /*
3569 * Byteswap an mmap'ed file if needed
3570 */
3571 file_private void
byteswap(struct magic * magic,uint32_t nmagic)3572 byteswap(struct magic *magic, uint32_t nmagic)
3573 {
3574 uint32_t i;
3575 for (i = 0; i < nmagic; i++)
3576 bs1(&magic[i]);
3577 }
3578
3579 file_protected uintmax_t
file_varint2uintmax_t(const unsigned char * us,int t,size_t * l)3580 file_varint2uintmax_t(const unsigned char *us, int t, size_t *l)
3581 {
3582 uintmax_t x = 0;
3583 const unsigned char *c;
3584 if (t == FILE_LEVARINT) {
3585 for (c = us; *c; c++) {
3586 if ((*c & 0x80) == 0)
3587 break;
3588 }
3589 if (l)
3590 *l = c - us + 1;
3591 for (; c >= us; c--) {
3592 x |= *c & 0x7f;
3593 x <<= 7;
3594 }
3595 } else {
3596 for (c = us; *c; c++) {
3597 x |= *c & 0x7f;
3598 if ((*c & 0x80) == 0)
3599 break;
3600 x <<= 7;
3601 }
3602 if (l)
3603 *l = c - us + 1;
3604 }
3605 return x;
3606 }
3607
3608
3609 /*
3610 * byteswap a single magic entry
3611 */
3612 file_private void
bs1(struct magic * m)3613 bs1(struct magic *m)
3614 {
3615 m->flag = file_swap2(m->flag);
3616 m->offset = file_swap4(CAST(uint32_t, m->offset));
3617 m->in_offset = file_swap4(CAST(uint32_t, m->in_offset));
3618 m->lineno = file_swap4(CAST(uint32_t, m->lineno));
3619 if (IS_STRING(m->type)) {
3620 m->str_range = file_swap4(m->str_range);
3621 m->str_flags = file_swap4(m->str_flags);
3622 } else {
3623 m->value.q = file_swap8(m->value.q);
3624 m->num_mask = file_swap8(m->num_mask);
3625 }
3626 }
3627
3628 file_protected size_t
file_pstring_length_size(struct magic_set * ms,const struct magic * m)3629 file_pstring_length_size(struct magic_set *ms, const struct magic *m)
3630 {
3631 switch (m->str_flags & PSTRING_LEN) {
3632 case PSTRING_1_LE:
3633 return 1;
3634 case PSTRING_2_LE:
3635 case PSTRING_2_BE:
3636 return 2;
3637 case PSTRING_4_LE:
3638 case PSTRING_4_BE:
3639 return 4;
3640 default:
3641 file_error(ms, 0, "corrupt magic file "
3642 "(bad pascal string length %d)",
3643 m->str_flags & PSTRING_LEN);
3644 return FILE_BADSIZE;
3645 }
3646 }
3647
3648 file_protected size_t
file_pstring_get_length(struct magic_set * ms,const struct magic * m,const char * ss)3649 file_pstring_get_length(struct magic_set *ms, const struct magic *m,
3650 const char *ss)
3651 {
3652 size_t len = 0;
3653 const unsigned char *s = RCAST(const unsigned char *, ss);
3654 unsigned int s3, s2, s1, s0;
3655
3656 switch (m->str_flags & PSTRING_LEN) {
3657 case PSTRING_1_LE:
3658 len = *s;
3659 break;
3660 case PSTRING_2_LE:
3661 s0 = s[0];
3662 s1 = s[1];
3663 len = (s1 << 8) | s0;
3664 break;
3665 case PSTRING_2_BE:
3666 s0 = s[0];
3667 s1 = s[1];
3668 len = (s0 << 8) | s1;
3669 break;
3670 case PSTRING_4_LE:
3671 s0 = s[0];
3672 s1 = s[1];
3673 s2 = s[2];
3674 s3 = s[3];
3675 len = (s3 << 24) | (s2 << 16) | (s1 << 8) | s0;
3676 break;
3677 case PSTRING_4_BE:
3678 s0 = s[0];
3679 s1 = s[1];
3680 s2 = s[2];
3681 s3 = s[3];
3682 len = (s0 << 24) | (s1 << 16) | (s2 << 8) | s3;
3683 break;
3684 default:
3685 file_error(ms, 0, "corrupt magic file "
3686 "(bad pascal string length %d)",
3687 m->str_flags & PSTRING_LEN);
3688 return FILE_BADSIZE;
3689 }
3690
3691 if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF) {
3692 size_t l = file_pstring_length_size(ms, m);
3693 if (l == FILE_BADSIZE)
3694 return l;
3695 len -= l;
3696 }
3697
3698 return len;
3699 }
3700
3701 file_protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3702 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3703 {
3704 uint32_t i, j;
3705 struct mlist *mlist, *ml;
3706
3707 mlist = ms->mlist[1];
3708
3709 for (ml = mlist->next; ml != mlist; ml = ml->next) {
3710 struct magic *ma = ml->magic;
3711 for (i = 0; i < ml->nmagic; i++) {
3712 if (ma[i].type != FILE_NAME)
3713 continue;
3714 if (strcmp(ma[i].value.s, name) == 0) {
3715 v->magic = &ma[i];
3716 v->magic_rxcomp = &(ml->magic_rxcomp[i]);
3717 for (j = i + 1; j < ml->nmagic; j++)
3718 if (ma[j].cont_level == 0)
3719 break;
3720 v->nmagic = j - i;
3721 return 0;
3722 }
3723 }
3724 }
3725 return -1;
3726 }
3727