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 1.326 2022/09/13 18:46:07 christos Exp $")
36 #endif /* lint */
37
38 #include "magic.h"
39 #include <stdlib.h>
40 #ifdef HAVE_UNISTD_H
41 #include <unistd.h>
42 #endif
43 #include <stddef.h>
44 #include <string.h>
45 #include <assert.h>
46 #include <ctype.h>
47 #include <fcntl.h>
48 #ifdef QUICK
49 #include <sys/mman.h>
50 #endif
51 #include <dirent.h>
52 #include <limits.h>
53 #ifdef HAVE_BYTESWAP_H
54 #include <byteswap.h>
55 #endif
56 #ifdef HAVE_SYS_BSWAP_H
57 #include <sys/bswap.h>
58 #endif
59
60
61 #define EATAB {while (isascii(CAST(unsigned char, *l)) && \
62 isspace(CAST(unsigned char, *l))) ++l;}
63 #define LOWCASE(l) (isupper(CAST(unsigned char, l)) ? \
64 tolower(CAST(unsigned char, l)) : (l))
65 /*
66 * Work around a bug in headers on Digital Unix.
67 * At least confirmed for: OSF1 V4.0 878
68 */
69 #if defined(__osf__) && defined(__DECC)
70 #ifdef MAP_FAILED
71 #undef MAP_FAILED
72 #endif
73 #endif
74
75 #ifndef MAP_FAILED
76 #define MAP_FAILED (void *) -1
77 #endif
78
79 #ifndef MAP_FILE
80 #define MAP_FILE 0
81 #endif
82
83 #define ALLOC_CHUNK CAST(size_t, 10)
84 #define ALLOC_INCR CAST(size_t, 200)
85
86 #define MAP_TYPE_USER 0
87 #define MAP_TYPE_MALLOC 1
88 #define MAP_TYPE_MMAP 2
89
90 struct magic_entry {
91 struct magic *mp;
92 uint32_t cont_count;
93 uint32_t max_count;
94 };
95
96 struct magic_entry_set {
97 struct magic_entry *me;
98 uint32_t count;
99 uint32_t max;
100 };
101
102 struct magic_map {
103 void *p;
104 size_t len;
105 int type;
106 struct magic *magic[MAGIC_SETS];
107 uint32_t nmagic[MAGIC_SETS];
108 };
109
110 int file_formats[FILE_NAMES_SIZE];
111 const size_t file_nformats = FILE_NAMES_SIZE;
112 const char *file_names[FILE_NAMES_SIZE];
113 const size_t file_nnames = FILE_NAMES_SIZE;
114
115 private int getvalue(struct magic_set *ms, struct magic *, const char **, int);
116 private int hextoint(int);
117 private const char *getstr(struct magic_set *, struct magic *, const char *,
118 int);
119 private int parse(struct magic_set *, struct magic_entry *, const char *,
120 size_t, int);
121 private void eatsize(const char **);
122 private int apprentice_1(struct magic_set *, const char *, int);
123 private ssize_t apprentice_magic_strength_1(const struct magic *);
124 private size_t apprentice_magic_strength(const struct magic *, size_t);
125 private int apprentice_sort(const void *, const void *);
126 private void apprentice_list(struct mlist *, int );
127 private struct magic_map *apprentice_load(struct magic_set *,
128 const char *, int);
129 private struct mlist *mlist_alloc(void);
130 private void mlist_free_all(struct magic_set *);
131 private void mlist_free(struct mlist *);
132 private void byteswap(struct magic *, uint32_t);
133 private void bs1(struct magic *);
134
135 #if defined(HAVE_BYTESWAP_H)
136 #define swap2(x) bswap_16(x)
137 #define swap4(x) bswap_32(x)
138 #define swap8(x) bswap_64(x)
139 #elif defined(HAVE_SYS_BSWAP_H)
140 #define swap2(x) bswap16(x)
141 #define swap4(x) bswap32(x)
142 #define swap8(x) bswap64(x)
143 #else
144 private uint16_t swap2(uint16_t);
145 private uint32_t swap4(uint32_t);
146 private uint64_t swap8(uint64_t);
147 #endif
148
149 private char *mkdbname(struct magic_set *, const char *, int);
150 private struct magic_map *apprentice_buf(struct magic_set *, struct magic *,
151 size_t);
152 private struct magic_map *apprentice_map(struct magic_set *, const char *);
153 private int check_buffer(struct magic_set *, struct magic_map *, const char *);
154 private void apprentice_unmap(struct magic_map *);
155 private int apprentice_compile(struct magic_set *, struct magic_map *,
156 const char *);
157 private int check_format_type(const char *, int, const char **);
158 private int check_format(struct magic_set *, struct magic *);
159 private int get_op(char);
160 private int parse_mime(struct magic_set *, struct magic_entry *, const char *,
161 size_t);
162 private int parse_strength(struct magic_set *, struct magic_entry *,
163 const char *, size_t);
164 private int parse_apple(struct magic_set *, struct magic_entry *, const char *,
165 size_t);
166 private int parse_ext(struct magic_set *, struct magic_entry *, const char *,
167 size_t);
168
169
170 private size_t magicsize = sizeof(struct magic);
171
172 private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
173
174 private struct {
175 const char *name;
176 size_t len;
177 int (*fun)(struct magic_set *, struct magic_entry *, const char *,
178 size_t);
179 } bang[] = {
180 #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
181 DECLARE_FIELD(mime),
182 DECLARE_FIELD(apple),
183 DECLARE_FIELD(ext),
184 DECLARE_FIELD(strength),
185 #undef DECLARE_FIELD
186 { NULL, 0, NULL }
187 };
188
189 #ifdef COMPILE_ONLY
190
191 int main(int, char *[]);
192
193 int
main(int argc,char * argv[])194 main(int argc, char *argv[])
195 {
196 int ret;
197 struct magic_set *ms;
198 char *progname;
199
200 if ((progname = strrchr(argv[0], '/')) != NULL)
201 progname++;
202 else
203 progname = argv[0];
204
205 if (argc != 2) {
206 (void)fprintf(stderr, "Usage: %s file\n", progname);
207 return 1;
208 }
209
210 if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
211 (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
212 return 1;
213 }
214 ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
215 if (ret == 1)
216 (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
217 magic_close(ms);
218 return ret;
219 }
220 #endif /* COMPILE_ONLY */
221
222 struct type_tbl_s {
223 const char name[16];
224 const size_t len;
225 const int type;
226 const int format;
227 };
228
229 /*
230 * XXX - the actual Single UNIX Specification says that "long" means "long",
231 * as in the C data type, but we treat it as meaning "4-byte integer".
232 * Given that the OS X version of file 5.04 did the same, I guess that passes
233 * the actual test; having "long" be dependent on how big a "long" is on
234 * the machine running "file" is silly.
235 */
236 static const struct type_tbl_s type_tbl[] = {
237 # define XX(s) s, (sizeof(s) - 1)
238 # define XX_NULL "", 0
239 { XX("invalid"), FILE_INVALID, FILE_FMT_NONE },
240 { XX("byte"), FILE_BYTE, FILE_FMT_NUM },
241 { XX("short"), FILE_SHORT, FILE_FMT_NUM },
242 { XX("default"), FILE_DEFAULT, FILE_FMT_NONE },
243 { XX("long"), FILE_LONG, FILE_FMT_NUM },
244 { XX("string"), FILE_STRING, FILE_FMT_STR },
245 { XX("date"), FILE_DATE, FILE_FMT_STR },
246 { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM },
247 { XX("belong"), FILE_BELONG, FILE_FMT_NUM },
248 { XX("bedate"), FILE_BEDATE, FILE_FMT_STR },
249 { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM },
250 { XX("lelong"), FILE_LELONG, FILE_FMT_NUM },
251 { XX("ledate"), FILE_LEDATE, FILE_FMT_STR },
252 { XX("pstring"), FILE_PSTRING, FILE_FMT_STR },
253 { XX("ldate"), FILE_LDATE, FILE_FMT_STR },
254 { XX("beldate"), FILE_BELDATE, FILE_FMT_STR },
255 { XX("leldate"), FILE_LELDATE, FILE_FMT_STR },
256 { XX("regex"), FILE_REGEX, FILE_FMT_STR },
257 { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR },
258 { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR },
259 { XX("search"), FILE_SEARCH, FILE_FMT_STR },
260 { XX("medate"), FILE_MEDATE, FILE_FMT_STR },
261 { XX("meldate"), FILE_MELDATE, FILE_FMT_STR },
262 { XX("melong"), FILE_MELONG, FILE_FMT_NUM },
263 { XX("quad"), FILE_QUAD, FILE_FMT_QUAD },
264 { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD },
265 { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD },
266 { XX("qdate"), FILE_QDATE, FILE_FMT_STR },
267 { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR },
268 { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR },
269 { XX("qldate"), FILE_QLDATE, FILE_FMT_STR },
270 { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR },
271 { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR },
272 { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT },
273 { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT },
274 { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT },
275 { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE },
276 { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE },
277 { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE },
278 { XX("leid3"), FILE_LEID3, FILE_FMT_NUM },
279 { XX("beid3"), FILE_BEID3, FILE_FMT_NUM },
280 { XX("indirect"), FILE_INDIRECT, FILE_FMT_NUM },
281 { XX("qwdate"), FILE_QWDATE, FILE_FMT_STR },
282 { XX("leqwdate"), FILE_LEQWDATE, FILE_FMT_STR },
283 { XX("beqwdate"), FILE_BEQWDATE, FILE_FMT_STR },
284 { XX("name"), FILE_NAME, FILE_FMT_NONE },
285 { XX("use"), FILE_USE, FILE_FMT_NONE },
286 { XX("clear"), FILE_CLEAR, FILE_FMT_NONE },
287 { XX("der"), FILE_DER, FILE_FMT_STR },
288 { XX("guid"), FILE_GUID, FILE_FMT_STR },
289 { XX("offset"), FILE_OFFSET, FILE_FMT_QUAD },
290 { XX("bevarint"), FILE_BEVARINT, FILE_FMT_STR },
291 { XX("levarint"), FILE_LEVARINT, FILE_FMT_STR },
292 { XX("msdosdate"), FILE_MSDOSDATE, FILE_FMT_STR },
293 { XX("lemsdosdate"), FILE_LEMSDOSDATE, FILE_FMT_STR },
294 { XX("bemsdosdate"), FILE_BEMSDOSDATE, FILE_FMT_STR },
295 { XX("msdostime"), FILE_MSDOSTIME, FILE_FMT_STR },
296 { XX("lemsdostime"), FILE_LEMSDOSTIME, FILE_FMT_STR },
297 { XX("bemsdostime"), FILE_BEMSDOSTIME, FILE_FMT_STR },
298 { XX("octal"), FILE_OCTAL, FILE_FMT_STR },
299 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
300 };
301
302 /*
303 * These are not types, and cannot be preceded by "u" to make them
304 * unsigned.
305 */
306 static const struct type_tbl_s special_tbl[] = {
307 { XX("der"), FILE_DER, FILE_FMT_STR },
308 { XX("name"), FILE_NAME, FILE_FMT_STR },
309 { XX("use"), FILE_USE, FILE_FMT_STR },
310 { XX("octal"), FILE_OCTAL, FILE_FMT_STR },
311 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
312 };
313 # undef XX
314 # undef XX_NULL
315
316 private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)317 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
318 {
319 const struct type_tbl_s *p;
320
321 for (p = tbl; p->len; p++) {
322 if (strncmp(l, p->name, p->len) == 0) {
323 if (t)
324 *t = l + p->len;
325 break;
326 }
327 }
328 return p->type;
329 }
330
331 private off_t
maxoff_t(void)332 maxoff_t(void) {
333 if (/*CONSTCOND*/sizeof(off_t) == sizeof(int))
334 return CAST(off_t, INT_MAX);
335 if (/*CONSTCOND*/sizeof(off_t) == sizeof(long))
336 return CAST(off_t, LONG_MAX);
337 return 0x7fffffff;
338 }
339
340 private int
get_standard_integer_type(const char * l,const char ** t)341 get_standard_integer_type(const char *l, const char **t)
342 {
343 int type;
344
345 if (isalpha(CAST(unsigned char, l[1]))) {
346 switch (l[1]) {
347 case 'C':
348 /* "dC" and "uC" */
349 type = FILE_BYTE;
350 break;
351 case 'S':
352 /* "dS" and "uS" */
353 type = FILE_SHORT;
354 break;
355 case 'I':
356 case 'L':
357 /*
358 * "dI", "dL", "uI", and "uL".
359 *
360 * XXX - the actual Single UNIX Specification says
361 * that "L" means "long", as in the C data type,
362 * but we treat it as meaning "4-byte integer".
363 * Given that the OS X version of file 5.04 did
364 * the same, I guess that passes the actual SUS
365 * validation suite; having "dL" be dependent on
366 * how big a "long" is on the machine running
367 * "file" is silly.
368 */
369 type = FILE_LONG;
370 break;
371 case 'Q':
372 /* "dQ" and "uQ" */
373 type = FILE_QUAD;
374 break;
375 default:
376 /* "d{anything else}", "u{anything else}" */
377 return FILE_INVALID;
378 }
379 l += 2;
380 } else if (isdigit(CAST(unsigned char, l[1]))) {
381 /*
382 * "d{num}" and "u{num}"; we only support {num} values
383 * of 1, 2, 4, and 8 - the Single UNIX Specification
384 * doesn't say anything about whether arbitrary
385 * values should be supported, but both the Solaris 10
386 * and OS X Mountain Lion versions of file passed the
387 * Single UNIX Specification validation suite, and
388 * neither of them support values bigger than 8 or
389 * non-power-of-2 values.
390 */
391 if (isdigit(CAST(unsigned char, l[2]))) {
392 /* Multi-digit, so > 9 */
393 return FILE_INVALID;
394 }
395 switch (l[1]) {
396 case '1':
397 type = FILE_BYTE;
398 break;
399 case '2':
400 type = FILE_SHORT;
401 break;
402 case '4':
403 type = FILE_LONG;
404 break;
405 case '8':
406 type = FILE_QUAD;
407 break;
408 default:
409 /* XXX - what about 3, 5, 6, or 7? */
410 return FILE_INVALID;
411 }
412 l += 2;
413 } else {
414 /*
415 * "d" or "u" by itself.
416 */
417 type = FILE_LONG;
418 ++l;
419 }
420 if (t)
421 *t = l;
422 return type;
423 }
424
425 private void
init_file_tables(void)426 init_file_tables(void)
427 {
428 static int done = 0;
429 const struct type_tbl_s *p;
430
431 if (done)
432 return;
433 done++;
434
435 for (p = type_tbl; p->len; p++) {
436 assert(p->type < FILE_NAMES_SIZE);
437 file_names[p->type] = p->name;
438 file_formats[p->type] = p->format;
439 }
440 assert(p - type_tbl == FILE_NAMES_SIZE);
441 }
442
443 private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)444 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
445 {
446 struct mlist *ml;
447
448 mlp->map = NULL;
449 if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
450 return -1;
451
452 ml->map = idx == 0 ? map : NULL;
453 ml->magic = map->magic[idx];
454 ml->nmagic = map->nmagic[idx];
455 if (ml->nmagic) {
456 ml->magic_rxcomp = CAST(file_regex_t **,
457 calloc(ml->nmagic, sizeof(*ml->magic_rxcomp)));
458 if (ml->magic_rxcomp == NULL) {
459 free(ml);
460 return -1;
461 }
462 } else
463 ml->magic_rxcomp = NULL;
464 mlp->prev->next = ml;
465 ml->prev = mlp->prev;
466 ml->next = mlp;
467 mlp->prev = ml;
468 return 0;
469 }
470
471 /*
472 * Handle one file or directory.
473 */
474 private int
apprentice_1(struct magic_set * ms,const char * fn,int action)475 apprentice_1(struct magic_set *ms, const char *fn, int action)
476 {
477 struct magic_map *map;
478 #ifndef COMPILE_ONLY
479 struct mlist *ml;
480 size_t i;
481 #endif
482
483 if (magicsize != FILE_MAGICSIZE) {
484 file_error(ms, 0, "magic element size %lu != %lu",
485 CAST(unsigned long, sizeof(*map->magic[0])),
486 CAST(unsigned long, FILE_MAGICSIZE));
487 return -1;
488 }
489
490 if (action == FILE_COMPILE) {
491 map = apprentice_load(ms, fn, action);
492 if (map == NULL)
493 return -1;
494 return apprentice_compile(ms, map, fn);
495 }
496
497 #ifndef COMPILE_ONLY
498 map = apprentice_map(ms, fn);
499 if (map == NULL) {
500 if (ms->flags & MAGIC_CHECK)
501 file_magwarn(ms, "using regular magic file `%s'", fn);
502 map = apprentice_load(ms, fn, action);
503 if (map == NULL)
504 return -1;
505 }
506
507 for (i = 0; i < MAGIC_SETS; i++) {
508 if (add_mlist(ms->mlist[i], map, i) == -1) {
509 /* failed to add to any list, free explicitly */
510 if (i == 0)
511 apprentice_unmap(map);
512 else
513 mlist_free_all(ms);
514 file_oomem(ms, sizeof(*ml));
515 return -1;
516 }
517 }
518
519 if (action == FILE_LIST) {
520 for (i = 0; i < MAGIC_SETS; i++) {
521 printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
522 i);
523 apprentice_list(ms->mlist[i], BINTEST);
524 printf("Text patterns:\n");
525 apprentice_list(ms->mlist[i], TEXTTEST);
526 }
527 }
528 return 0;
529 #else
530 return 0;
531 #endif /* COMPILE_ONLY */
532 }
533
534 protected void
file_ms_free(struct magic_set * ms)535 file_ms_free(struct magic_set *ms)
536 {
537 size_t i;
538 if (ms == NULL)
539 return;
540 for (i = 0; i < MAGIC_SETS; i++)
541 mlist_free(ms->mlist[i]);
542 free(ms->o.pbuf);
543 free(ms->o.buf);
544 free(ms->c.li);
545 #ifdef USE_C_LOCALE
546 freelocale(ms->c_lc_ctype);
547 #endif
548 free(ms);
549 }
550
551 protected struct magic_set *
file_ms_alloc(int flags)552 file_ms_alloc(int flags)
553 {
554 struct magic_set *ms;
555 size_t i, len;
556
557 if ((ms = CAST(struct magic_set *, calloc(CAST(size_t, 1u),
558 sizeof(struct magic_set)))) == NULL)
559 return NULL;
560
561 if (magic_setflags(ms, flags) == -1) {
562 errno = EINVAL;
563 goto free;
564 }
565
566 ms->o.buf = ms->o.pbuf = NULL;
567 ms->o.blen = 0;
568 len = (ms->c.len = 10) * sizeof(*ms->c.li);
569
570 if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
571 goto free;
572
573 ms->event_flags = 0;
574 ms->error = -1;
575 for (i = 0; i < MAGIC_SETS; i++)
576 ms->mlist[i] = NULL;
577 ms->file = "unknown";
578 ms->line = 0;
579 ms->indir_max = FILE_INDIR_MAX;
580 ms->name_max = FILE_NAME_MAX;
581 ms->elf_shnum_max = FILE_ELF_SHNUM_MAX;
582 ms->elf_phnum_max = FILE_ELF_PHNUM_MAX;
583 ms->elf_notes_max = FILE_ELF_NOTES_MAX;
584 ms->regex_max = FILE_REGEX_MAX;
585 ms->bytes_max = FILE_BYTES_MAX;
586 ms->encoding_max = FILE_ENCODING_MAX;
587 #ifdef USE_C_LOCALE
588 ms->c_lc_ctype = newlocale(LC_CTYPE_MASK, "C", 0);
589 assert(ms->c_lc_ctype != NULL);
590 #endif
591 return ms;
592 free:
593 free(ms);
594 return NULL;
595 }
596
597 private void
apprentice_unmap(struct magic_map * map)598 apprentice_unmap(struct magic_map *map)
599 {
600 size_t i;
601 char *p;
602 if (map == NULL)
603 return;
604
605 switch (map->type) {
606 case MAP_TYPE_USER:
607 break;
608 case MAP_TYPE_MALLOC:
609 p = CAST(char *, map->p);
610 for (i = 0; i < MAGIC_SETS; i++) {
611 char *b = RCAST(char *, map->magic[i]);
612 if (p != NULL && b >= p && b <= p + map->len)
613 continue;
614 free(b);
615 }
616 free(p);
617 break;
618 #ifdef QUICK
619 case MAP_TYPE_MMAP:
620 if (map->p && map->p != MAP_FAILED)
621 (void)munmap(map->p, map->len);
622 break;
623 #endif
624 default:
625 fprintf(stderr, "Bad map type %d", map->type);
626 abort();
627 }
628 free(map);
629 }
630
631 private struct mlist *
mlist_alloc(void)632 mlist_alloc(void)
633 {
634 struct mlist *mlist;
635 if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
636 return NULL;
637 }
638 mlist->next = mlist->prev = mlist;
639 return mlist;
640 }
641
642 private void
mlist_free_all(struct magic_set * ms)643 mlist_free_all(struct magic_set *ms)
644 {
645 size_t i;
646
647 for (i = 0; i < MAGIC_SETS; i++) {
648 mlist_free(ms->mlist[i]);
649 ms->mlist[i] = NULL;
650 }
651 }
652
653 private void
mlist_free_one(struct mlist * ml)654 mlist_free_one(struct mlist *ml)
655 {
656 size_t i;
657
658 if (ml->map)
659 apprentice_unmap(CAST(struct magic_map *, ml->map));
660
661 for (i = 0; i < ml->nmagic; ++i) {
662 if (ml->magic_rxcomp[i]) {
663 file_regfree(ml->magic_rxcomp[i]);
664 free(ml->magic_rxcomp[i]);
665 ml->magic_rxcomp[i] = NULL;
666 }
667 }
668 free(ml->magic_rxcomp);
669 ml->magic_rxcomp = NULL;
670 free(ml);
671 }
672
673 private void
mlist_free(struct mlist * mlist)674 mlist_free(struct mlist *mlist)
675 {
676 struct mlist *ml, *next;
677
678 if (mlist == NULL)
679 return;
680
681 for (ml = mlist->next; ml != mlist;) {
682 next = ml->next;
683 mlist_free_one(ml);
684 ml = next;
685 }
686 mlist_free_one(mlist);
687 }
688
689 #ifndef COMPILE_ONLY
690 /* void **bufs: an array of compiled magic files */
691 protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)692 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
693 size_t *sizes, size_t nbufs)
694 {
695 size_t i, j;
696 struct mlist *ml;
697 struct magic_map *map;
698
699 if (nbufs == 0)
700 return -1;
701
702 (void)file_reset(ms, 0);
703
704 init_file_tables();
705
706 for (i = 0; i < MAGIC_SETS; i++) {
707 mlist_free(ms->mlist[i]);
708 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
709 file_oomem(ms, sizeof(*ms->mlist[i]));
710 goto fail;
711 }
712 }
713
714 for (i = 0; i < nbufs; i++) {
715 map = apprentice_buf(ms, bufs[i], sizes[i]);
716 if (map == NULL)
717 goto fail;
718
719 for (j = 0; j < MAGIC_SETS; j++) {
720 if (add_mlist(ms->mlist[j], map, j) == -1) {
721 file_oomem(ms, sizeof(*ml));
722 goto fail;
723 }
724 }
725 }
726
727 return 0;
728 fail:
729 mlist_free_all(ms);
730 return -1;
731 }
732 #endif
733
734 /* const char *fn: list of magic files and directories */
735 protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)736 file_apprentice(struct magic_set *ms, const char *fn, int action)
737 {
738 char *p, *mfn;
739 int fileerr, errs = -1;
740 size_t i, j;
741
742 (void)file_reset(ms, 0);
743
744 if ((fn = magic_getpath(fn, action)) == NULL)
745 return -1;
746
747 init_file_tables();
748
749 if ((mfn = strdup(fn)) == NULL) {
750 file_oomem(ms, strlen(fn));
751 return -1;
752 }
753
754 for (i = 0; i < MAGIC_SETS; i++) {
755 mlist_free(ms->mlist[i]);
756 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
757 file_oomem(ms, sizeof(*ms->mlist[i]));
758 for (j = 0; j < i; j++) {
759 mlist_free(ms->mlist[j]);
760 ms->mlist[j] = NULL;
761 }
762 free(mfn);
763 return -1;
764 }
765 }
766 fn = mfn;
767
768 while (fn) {
769 p = CCAST(char *, strchr(fn, PATHSEP));
770 if (p)
771 *p++ = '\0';
772 if (*fn == '\0')
773 break;
774 fileerr = apprentice_1(ms, fn, action);
775 errs = MAX(errs, fileerr);
776 fn = p;
777 }
778
779 free(mfn);
780
781 if (errs == -1) {
782 for (i = 0; i < MAGIC_SETS; i++) {
783 mlist_free(ms->mlist[i]);
784 ms->mlist[i] = NULL;
785 }
786 file_error(ms, 0, "could not find any valid magic files!");
787 return -1;
788 }
789
790 #if 0
791 /*
792 * Always leave the database loaded
793 */
794 if (action == FILE_LOAD)
795 return 0;
796
797 for (i = 0; i < MAGIC_SETS; i++) {
798 mlist_free(ms->mlist[i]);
799 ms->mlist[i] = NULL;
800 }
801 #endif
802
803 switch (action) {
804 case FILE_LOAD:
805 case FILE_COMPILE:
806 case FILE_CHECK:
807 case FILE_LIST:
808 return 0;
809 default:
810 file_error(ms, 0, "Invalid action %d", action);
811 return -1;
812 }
813 }
814
815 /*
816 * Compute the real length of a magic expression, for the purposes
817 * of determining how "strong" a magic expression is (approximating
818 * how specific its matches are):
819 * - magic characters count 0 unless escaped.
820 * - [] expressions count 1
821 * - {} expressions count 0
822 * - regular characters or escaped magic characters count 1
823 * - 0 length expressions count as one
824 */
825 private size_t
nonmagic(const char * str)826 nonmagic(const char *str)
827 {
828 const char *p;
829 size_t rv = 0;
830
831 for (p = str; *p; p++)
832 switch (*p) {
833 case '\\': /* Escaped anything counts 1 */
834 if (!*++p)
835 p--;
836 rv++;
837 continue;
838 case '?': /* Magic characters count 0 */
839 case '*':
840 case '.':
841 case '+':
842 case '^':
843 case '$':
844 continue;
845 case '[': /* Bracketed expressions count 1 the ']' */
846 while (*p && *p != ']')
847 p++;
848 p--;
849 continue;
850 case '{': /* Braced expressions count 0 */
851 while (*p && *p != '}')
852 p++;
853 if (!*p)
854 p--;
855 continue;
856 default: /* Anything else counts 1 */
857 rv++;
858 continue;
859 }
860
861 return rv == 0 ? 1 : rv; /* Return at least 1 */
862 }
863
864
865 private size_t
typesize(int type)866 typesize(int type)
867 {
868 switch (type) {
869 case FILE_BYTE:
870 return 1;
871
872 case FILE_SHORT:
873 case FILE_LESHORT:
874 case FILE_BESHORT:
875 case FILE_MSDOSDATE:
876 case FILE_BEMSDOSDATE:
877 case FILE_LEMSDOSDATE:
878 case FILE_MSDOSTIME:
879 case FILE_BEMSDOSTIME:
880 case FILE_LEMSDOSTIME:
881 return 2;
882
883 case FILE_LONG:
884 case FILE_LELONG:
885 case FILE_BELONG:
886 case FILE_MELONG:
887 return 4;
888
889 case FILE_DATE:
890 case FILE_LEDATE:
891 case FILE_BEDATE:
892 case FILE_MEDATE:
893 case FILE_LDATE:
894 case FILE_LELDATE:
895 case FILE_BELDATE:
896 case FILE_MELDATE:
897 case FILE_FLOAT:
898 case FILE_BEFLOAT:
899 case FILE_LEFLOAT:
900 case FILE_BEID3:
901 case FILE_LEID3:
902 return 4;
903
904 case FILE_QUAD:
905 case FILE_BEQUAD:
906 case FILE_LEQUAD:
907 case FILE_QDATE:
908 case FILE_LEQDATE:
909 case FILE_BEQDATE:
910 case FILE_QLDATE:
911 case FILE_LEQLDATE:
912 case FILE_BEQLDATE:
913 case FILE_QWDATE:
914 case FILE_LEQWDATE:
915 case FILE_BEQWDATE:
916 case FILE_DOUBLE:
917 case FILE_BEDOUBLE:
918 case FILE_LEDOUBLE:
919 case FILE_OFFSET:
920 case FILE_BEVARINT:
921 case FILE_LEVARINT:
922 return 8;
923
924 case FILE_GUID:
925 return 16;
926
927 default:
928 return FILE_BADSIZE;
929 }
930 }
931
932 /*
933 * Get weight of this magic entry, for sorting purposes.
934 */
935 private ssize_t
apprentice_magic_strength_1(const struct magic * m)936 apprentice_magic_strength_1(const struct magic *m)
937 {
938 #define MULT 10U
939 size_t ts, v;
940 ssize_t val = 2 * MULT; /* baseline strength */
941
942 switch (m->type) {
943 case FILE_DEFAULT: /* make sure this sorts last */
944 if (m->factor_op != FILE_FACTOR_OP_NONE) {
945 fprintf(stderr, "Bad factor_op %d", m->factor_op);
946 abort();
947 }
948 return 0;
949
950 case FILE_BYTE:
951 case FILE_SHORT:
952 case FILE_LESHORT:
953 case FILE_BESHORT:
954 case FILE_LONG:
955 case FILE_LELONG:
956 case FILE_BELONG:
957 case FILE_MELONG:
958 case FILE_DATE:
959 case FILE_LEDATE:
960 case FILE_BEDATE:
961 case FILE_MEDATE:
962 case FILE_LDATE:
963 case FILE_LELDATE:
964 case FILE_BELDATE:
965 case FILE_MELDATE:
966 case FILE_FLOAT:
967 case FILE_BEFLOAT:
968 case FILE_LEFLOAT:
969 case FILE_QUAD:
970 case FILE_BEQUAD:
971 case FILE_LEQUAD:
972 case FILE_QDATE:
973 case FILE_LEQDATE:
974 case FILE_BEQDATE:
975 case FILE_QLDATE:
976 case FILE_LEQLDATE:
977 case FILE_BEQLDATE:
978 case FILE_QWDATE:
979 case FILE_LEQWDATE:
980 case FILE_BEQWDATE:
981 case FILE_DOUBLE:
982 case FILE_BEDOUBLE:
983 case FILE_LEDOUBLE:
984 case FILE_BEVARINT:
985 case FILE_LEVARINT:
986 case FILE_GUID:
987 case FILE_BEID3:
988 case FILE_LEID3:
989 case FILE_OFFSET:
990 case FILE_MSDOSDATE:
991 case FILE_BEMSDOSDATE:
992 case FILE_LEMSDOSDATE:
993 case FILE_MSDOSTIME:
994 case FILE_BEMSDOSTIME:
995 case FILE_LEMSDOSTIME:
996 ts = typesize(m->type);
997 if (ts == FILE_BADSIZE) {
998 (void)fprintf(stderr, "Bad size for type %d\n",
999 m->type);
1000 abort();
1001 }
1002 val += ts * MULT;
1003 break;
1004
1005 case FILE_PSTRING:
1006 case FILE_STRING:
1007 case FILE_OCTAL:
1008 val += m->vallen * MULT;
1009 break;
1010
1011 case FILE_BESTRING16:
1012 case FILE_LESTRING16:
1013 val += m->vallen * MULT / 2;
1014 break;
1015
1016 case FILE_SEARCH:
1017 if (m->vallen == 0)
1018 break;
1019 val += m->vallen * MAX(MULT / m->vallen, 1);
1020 break;
1021
1022 case FILE_REGEX:
1023 v = nonmagic(m->value.s);
1024 val += v * MAX(MULT / v, 1);
1025 break;
1026
1027 case FILE_INDIRECT:
1028 case FILE_NAME:
1029 case FILE_USE:
1030 case FILE_CLEAR:
1031 break;
1032
1033 case FILE_DER:
1034 val += MULT;
1035 break;
1036
1037 default:
1038 (void)fprintf(stderr, "Bad type %d\n", m->type);
1039 abort();
1040 }
1041
1042 switch (m->reln) {
1043 case 'x': /* matches anything penalize */
1044 case '!': /* matches almost anything penalize */
1045 val = 0;
1046 break;
1047
1048 case '=': /* Exact match, prefer */
1049 val += MULT;
1050 break;
1051
1052 case '>':
1053 case '<': /* comparison match reduce strength */
1054 val -= 2 * MULT;
1055 break;
1056
1057 case '^':
1058 case '&': /* masking bits, we could count them too */
1059 val -= MULT;
1060 break;
1061
1062 default:
1063 (void)fprintf(stderr, "Bad relation %c\n", m->reln);
1064 abort();
1065 }
1066
1067 return val;
1068 }
1069
1070
1071 /*ARGSUSED*/
1072 private size_t
apprentice_magic_strength(const struct magic * m,size_t nmagic)1073 apprentice_magic_strength(const struct magic *m,
1074 size_t nmagic __attribute__((__unused__)))
1075 {
1076 ssize_t val = apprentice_magic_strength_1(m);
1077
1078 #ifdef notyet
1079 if (m->desc[0] == '\0') {
1080 size_t i;
1081 /*
1082 * Magic entries with no description get their continuations
1083 * added
1084 */
1085 for (i = 1; m[i].cont_level != 0 && i < MIN(nmagic, 3); i++) {
1086 ssize_t v = apprentice_magic_strength_1(&m[i]) >>
1087 (i + 1);
1088 val += v;
1089 if (m[i].desc[0] != '\0')
1090 break;
1091 }
1092 }
1093 #endif
1094
1095 switch (m->factor_op) {
1096 case FILE_FACTOR_OP_NONE:
1097 break;
1098 case FILE_FACTOR_OP_PLUS:
1099 val += m->factor;
1100 break;
1101 case FILE_FACTOR_OP_MINUS:
1102 val -= m->factor;
1103 break;
1104 case FILE_FACTOR_OP_TIMES:
1105 val *= m->factor;
1106 break;
1107 case FILE_FACTOR_OP_DIV:
1108 val /= m->factor;
1109 break;
1110 default:
1111 (void)fprintf(stderr, "Bad factor_op %u\n", m->factor_op);
1112 abort();
1113 }
1114
1115 if (val <= 0) /* ensure we only return 0 for FILE_DEFAULT */
1116 val = 1;
1117
1118 #ifndef notyet
1119 /*
1120 * Magic entries with no description get a bonus because they depend
1121 * on subsequent magic entries to print something.
1122 */
1123 if (m->desc[0] == '\0')
1124 val++;
1125 #endif
1126
1127 return val;
1128 }
1129
1130 /*
1131 * Sort callback for sorting entries by "strength" (basically length)
1132 */
1133 private int
apprentice_sort(const void * a,const void * b)1134 apprentice_sort(const void *a, const void *b)
1135 {
1136 const struct magic_entry *ma = CAST(const struct magic_entry *, a);
1137 const struct magic_entry *mb = CAST(const struct magic_entry *, b);
1138 size_t sa = apprentice_magic_strength(ma->mp, ma->cont_count);
1139 size_t sb = apprentice_magic_strength(mb->mp, mb->cont_count);
1140 if (sa == sb)
1141 return 0;
1142 else if (sa > sb)
1143 return -1;
1144 else
1145 return 1;
1146 }
1147
1148 /*
1149 * Shows sorted patterns list in the order which is used for the matching
1150 */
1151 private void
apprentice_list(struct mlist * mlist,int mode)1152 apprentice_list(struct mlist *mlist, int mode)
1153 {
1154 uint32_t magindex, descindex, mimeindex, lineindex;
1155 struct mlist *ml;
1156 for (ml = mlist->next; ml != mlist; ml = ml->next) {
1157 for (magindex = 0; magindex < ml->nmagic; magindex++) {
1158 struct magic *m = &ml->magic[magindex];
1159 if ((m->flag & mode) != mode) {
1160 /* Skip sub-tests */
1161 while (magindex + 1 < ml->nmagic &&
1162 ml->magic[magindex + 1].cont_level != 0)
1163 ++magindex;
1164 continue; /* Skip to next top-level test*/
1165 }
1166
1167 /*
1168 * Try to iterate over the tree until we find item with
1169 * description/mimetype.
1170 */
1171 lineindex = descindex = mimeindex = magindex;
1172 for (magindex++; magindex < ml->nmagic &&
1173 ml->magic[magindex].cont_level != 0; magindex++) {
1174 if (*ml->magic[descindex].desc == '\0'
1175 && *ml->magic[magindex].desc)
1176 descindex = magindex;
1177 if (*ml->magic[mimeindex].mimetype == '\0'
1178 && *ml->magic[magindex].mimetype)
1179 mimeindex = magindex;
1180 }
1181
1182 printf("Strength = %3" SIZE_T_FORMAT "u@%u: %s [%s]\n",
1183 apprentice_magic_strength(m, ml->nmagic - magindex),
1184 ml->magic[lineindex].lineno,
1185 ml->magic[descindex].desc,
1186 ml->magic[mimeindex].mimetype);
1187 }
1188 }
1189 }
1190
1191 private void
set_test_type(struct magic * mstart,struct magic * m)1192 set_test_type(struct magic *mstart, struct magic *m)
1193 {
1194 switch (m->type) {
1195 case FILE_BYTE:
1196 case FILE_SHORT:
1197 case FILE_LONG:
1198 case FILE_DATE:
1199 case FILE_BESHORT:
1200 case FILE_BELONG:
1201 case FILE_BEDATE:
1202 case FILE_LESHORT:
1203 case FILE_LELONG:
1204 case FILE_LEDATE:
1205 case FILE_LDATE:
1206 case FILE_BELDATE:
1207 case FILE_LELDATE:
1208 case FILE_MEDATE:
1209 case FILE_MELDATE:
1210 case FILE_MELONG:
1211 case FILE_QUAD:
1212 case FILE_LEQUAD:
1213 case FILE_BEQUAD:
1214 case FILE_QDATE:
1215 case FILE_LEQDATE:
1216 case FILE_BEQDATE:
1217 case FILE_QLDATE:
1218 case FILE_LEQLDATE:
1219 case FILE_BEQLDATE:
1220 case FILE_QWDATE:
1221 case FILE_LEQWDATE:
1222 case FILE_BEQWDATE:
1223 case FILE_FLOAT:
1224 case FILE_BEFLOAT:
1225 case FILE_LEFLOAT:
1226 case FILE_DOUBLE:
1227 case FILE_BEDOUBLE:
1228 case FILE_LEDOUBLE:
1229 case FILE_BEVARINT:
1230 case FILE_LEVARINT:
1231 case FILE_DER:
1232 case FILE_GUID:
1233 case FILE_OFFSET:
1234 case FILE_MSDOSDATE:
1235 case FILE_BEMSDOSDATE:
1236 case FILE_LEMSDOSDATE:
1237 case FILE_MSDOSTIME:
1238 case FILE_BEMSDOSTIME:
1239 case FILE_LEMSDOSTIME:
1240 case FILE_OCTAL:
1241 mstart->flag |= BINTEST;
1242 break;
1243 case FILE_STRING:
1244 case FILE_PSTRING:
1245 case FILE_BESTRING16:
1246 case FILE_LESTRING16:
1247 /* Allow text overrides */
1248 if (mstart->str_flags & STRING_TEXTTEST)
1249 mstart->flag |= TEXTTEST;
1250 else
1251 mstart->flag |= BINTEST;
1252 break;
1253 case FILE_REGEX:
1254 case FILE_SEARCH:
1255 /* Check for override */
1256 if (mstart->str_flags & STRING_BINTEST)
1257 mstart->flag |= BINTEST;
1258 if (mstart->str_flags & STRING_TEXTTEST)
1259 mstart->flag |= TEXTTEST;
1260
1261 if (mstart->flag & (TEXTTEST|BINTEST))
1262 break;
1263
1264 /* binary test if pattern is not text */
1265 if (file_looks_utf8(m->value.us, CAST(size_t, m->vallen), NULL,
1266 NULL) <= 0)
1267 mstart->flag |= BINTEST;
1268 else
1269 mstart->flag |= TEXTTEST;
1270 break;
1271 case FILE_DEFAULT:
1272 /* can't deduce anything; we shouldn't see this at the
1273 top level anyway */
1274 break;
1275 case FILE_INVALID:
1276 default:
1277 /* invalid search type, but no need to complain here */
1278 break;
1279 }
1280 }
1281
1282 private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1283 addentry(struct magic_set *ms, struct magic_entry *me,
1284 struct magic_entry_set *mset)
1285 {
1286 size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1287 if (mset[i].me == NULL || mset[i].count == mset[i].max) {
1288 struct magic_entry *mp;
1289
1290 size_t incr = mset[i].max + ALLOC_INCR;
1291 if ((mp = CAST(struct magic_entry *,
1292 realloc(mset[i].me, sizeof(*mp) * incr))) ==
1293 NULL) {
1294 file_oomem(ms, sizeof(*mp) * incr);
1295 return -1;
1296 }
1297 (void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1298 ALLOC_INCR);
1299 mset[i].me = mp;
1300 mset[i].max = CAST(uint32_t, incr);
1301 assert(mset[i].max == incr);
1302 }
1303 mset[i].me[mset[i].count++] = *me;
1304 memset(me, 0, sizeof(*me));
1305 return 0;
1306 }
1307
1308 /*
1309 * Load and parse one file.
1310 */
1311 private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1312 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1313 struct magic_entry_set *mset)
1314 {
1315 size_t lineno = 0, llen = 0;
1316 char *line = NULL;
1317 ssize_t len;
1318 struct magic_entry me;
1319
1320 FILE *f = fopen(ms->file = fn, "r");
1321 if (f == NULL) {
1322 if (errno != ENOENT)
1323 file_error(ms, errno, "cannot read magic file `%s'",
1324 fn);
1325 (*errs)++;
1326 return;
1327 }
1328
1329 memset(&me, 0, sizeof(me));
1330 /* read and parse this file */
1331 for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1332 ms->line++) {
1333 if (len == 0) /* null line, garbage, etc */
1334 continue;
1335 if (line[len - 1] == '\n') {
1336 lineno++;
1337 line[len - 1] = '\0'; /* delete newline */
1338 }
1339 switch (line[0]) {
1340 case '\0': /* empty, do not parse */
1341 case '#': /* comment, do not parse */
1342 continue;
1343 case '!':
1344 if (line[1] == ':') {
1345 size_t i;
1346
1347 for (i = 0; bang[i].name != NULL; i++) {
1348 if (CAST(size_t, len - 2) > bang[i].len &&
1349 memcmp(bang[i].name, line + 2,
1350 bang[i].len) == 0)
1351 break;
1352 }
1353 if (bang[i].name == NULL) {
1354 file_error(ms, 0,
1355 "Unknown !: entry `%s'", line);
1356 (*errs)++;
1357 continue;
1358 }
1359 if (me.mp == NULL) {
1360 file_error(ms, 0,
1361 "No current entry for :!%s type",
1362 bang[i].name);
1363 (*errs)++;
1364 continue;
1365 }
1366 if ((*bang[i].fun)(ms, &me,
1367 line + bang[i].len + 2,
1368 len - bang[i].len - 2) != 0) {
1369 (*errs)++;
1370 continue;
1371 }
1372 continue;
1373 }
1374 /*FALLTHROUGH*/
1375 default:
1376 again:
1377 switch (parse(ms, &me, line, lineno, action)) {
1378 case 0:
1379 continue;
1380 case 1:
1381 (void)addentry(ms, &me, mset);
1382 goto again;
1383 default:
1384 (*errs)++;
1385 break;
1386 }
1387 }
1388 }
1389 if (me.mp)
1390 (void)addentry(ms, &me, mset);
1391 free(line);
1392 (void)fclose(f);
1393 }
1394
1395 /*
1396 * parse a file or directory of files
1397 * const char *fn: name of magic file or directory
1398 */
1399 private int
cmpstrp(const void * p1,const void * p2)1400 cmpstrp(const void *p1, const void *p2)
1401 {
1402 return strcmp(*RCAST(char *const *, p1), *RCAST(char *const *, p2));
1403 }
1404
1405
1406 private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1407 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1408 uint32_t starttest)
1409 {
1410 static const char text[] = "text";
1411 static const char binary[] = "binary";
1412 static const size_t len = sizeof(text);
1413
1414 uint32_t i = starttest;
1415
1416 do {
1417 set_test_type(me[starttest].mp, me[i].mp);
1418 if ((ms->flags & MAGIC_DEBUG) == 0)
1419 continue;
1420 (void)fprintf(stderr, "%s%s%s: %s\n",
1421 me[i].mp->mimetype,
1422 me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1423 me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1424 me[i].mp->flag & BINTEST ? binary : text);
1425 if (me[i].mp->flag & BINTEST) {
1426 char *p = strstr(me[i].mp->desc, text);
1427 if (p && (p == me[i].mp->desc ||
1428 isspace(CAST(unsigned char, p[-1]))) &&
1429 (p + len - me[i].mp->desc == MAXstring
1430 || (p[len] == '\0' ||
1431 isspace(CAST(unsigned char, p[len])))))
1432 (void)fprintf(stderr, "*** Possible "
1433 "binary test for text type\n");
1434 }
1435 } while (++i < nme && me[i].mp->cont_level != 0);
1436 return i;
1437 }
1438
1439 private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1440 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1441 {
1442 uint32_t i;
1443 for (i = 0; i < nme; i++) {
1444 if (me[i].mp->cont_level == 0 &&
1445 me[i].mp->type == FILE_DEFAULT) {
1446 while (++i < nme)
1447 if (me[i].mp->cont_level == 0)
1448 break;
1449 if (i != nme) {
1450 /* XXX - Ugh! */
1451 ms->line = me[i].mp->lineno;
1452 file_magwarn(ms,
1453 "level 0 \"default\" did not sort last");
1454 }
1455 return;
1456 }
1457 }
1458 }
1459
1460 private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1461 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1462 struct magic **ma, uint32_t *nma)
1463 {
1464 uint32_t i, mentrycount = 0;
1465 size_t slen;
1466
1467 for (i = 0; i < nme; i++)
1468 mentrycount += me[i].cont_count;
1469
1470 if (mentrycount == 0) {
1471 *ma = NULL;
1472 *nma = 0;
1473 return 0;
1474 }
1475
1476 slen = sizeof(**ma) * mentrycount;
1477 if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1478 file_oomem(ms, slen);
1479 return -1;
1480 }
1481
1482 mentrycount = 0;
1483 for (i = 0; i < nme; i++) {
1484 (void)memcpy(*ma + mentrycount, me[i].mp,
1485 me[i].cont_count * sizeof(**ma));
1486 mentrycount += me[i].cont_count;
1487 }
1488 *nma = mentrycount;
1489 return 0;
1490 }
1491
1492 private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1493 magic_entry_free(struct magic_entry *me, uint32_t nme)
1494 {
1495 uint32_t i;
1496 if (me == NULL)
1497 return;
1498 for (i = 0; i < nme; i++)
1499 free(me[i].mp);
1500 free(me);
1501 }
1502
1503 private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1504 apprentice_load(struct magic_set *ms, const char *fn, int action)
1505 {
1506 int errs = 0;
1507 uint32_t i, j;
1508 size_t files = 0, maxfiles = 0;
1509 char **filearr = NULL, *mfn;
1510 struct stat st;
1511 struct magic_map *map;
1512 struct magic_entry_set mset[MAGIC_SETS];
1513 DIR *dir;
1514 struct dirent *d;
1515
1516 memset(mset, 0, sizeof(mset));
1517 ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */
1518
1519
1520 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1521 {
1522 file_oomem(ms, sizeof(*map));
1523 return NULL;
1524 }
1525 map->type = MAP_TYPE_MALLOC;
1526
1527 /* print silly verbose header for USG compat. */
1528 if (action == FILE_CHECK)
1529 (void)fprintf(stderr, "%s\n", usg_hdr);
1530
1531 /* load directory or file */
1532 if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1533 dir = opendir(fn);
1534 if (!dir) {
1535 errs++;
1536 goto out;
1537 }
1538 while ((d = readdir(dir)) != NULL) {
1539 if (d->d_name[0] == '.')
1540 continue;
1541 if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1542 file_oomem(ms,
1543 strlen(fn) + strlen(d->d_name) + 2);
1544 errs++;
1545 closedir(dir);
1546 goto out;
1547 }
1548 if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1549 free(mfn);
1550 continue;
1551 }
1552 if (files >= maxfiles) {
1553 size_t mlen;
1554 char **nfilearr;
1555 maxfiles = (maxfiles + 1) * 2;
1556 mlen = maxfiles * sizeof(*filearr);
1557 if ((nfilearr = CAST(char **,
1558 realloc(filearr, mlen))) == NULL) {
1559 file_oomem(ms, mlen);
1560 free(mfn);
1561 closedir(dir);
1562 errs++;
1563 goto out;
1564 }
1565 filearr = nfilearr;
1566 }
1567 filearr[files++] = mfn;
1568 }
1569 closedir(dir);
1570 if (filearr) {
1571 qsort(filearr, files, sizeof(*filearr), cmpstrp);
1572 for (i = 0; i < files; i++) {
1573 load_1(ms, action, filearr[i], &errs, mset);
1574 free(filearr[i]);
1575 }
1576 free(filearr);
1577 filearr = NULL;
1578 }
1579 } else
1580 load_1(ms, action, fn, &errs, mset);
1581 if (errs)
1582 goto out;
1583
1584 for (j = 0; j < MAGIC_SETS; j++) {
1585 /* Set types of tests */
1586 for (i = 0; i < mset[j].count; ) {
1587 if (mset[j].me[i].mp->cont_level != 0) {
1588 i++;
1589 continue;
1590 }
1591 i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1592 }
1593 if (mset[j].me)
1594 qsort(mset[j].me, mset[j].count, sizeof(*mset[j].me),
1595 apprentice_sort);
1596
1597 /*
1598 * Make sure that any level 0 "default" line is last
1599 * (if one exists).
1600 */
1601 set_last_default(ms, mset[j].me, mset[j].count);
1602
1603 /* coalesce per file arrays into a single one, if needed */
1604 if (mset[j].count == 0)
1605 continue;
1606
1607 if (coalesce_entries(ms, mset[j].me, mset[j].count,
1608 &map->magic[j], &map->nmagic[j]) == -1) {
1609 errs++;
1610 goto out;
1611 }
1612 }
1613
1614 out:
1615 free(filearr);
1616 for (j = 0; j < MAGIC_SETS; j++)
1617 magic_entry_free(mset[j].me, mset[j].count);
1618
1619 if (errs) {
1620 apprentice_unmap(map);
1621 return NULL;
1622 }
1623 return map;
1624 }
1625
1626 /*
1627 * extend the sign bit if the comparison is to be signed
1628 */
1629 protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1630 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1631 {
1632 if (!(m->flag & UNSIGNED)) {
1633 switch(m->type) {
1634 /*
1635 * Do not remove the casts below. They are
1636 * vital. When later compared with the data,
1637 * the sign extension must have happened.
1638 */
1639 case FILE_BYTE:
1640 v = CAST(signed char, v);
1641 break;
1642 case FILE_SHORT:
1643 case FILE_BESHORT:
1644 case FILE_LESHORT:
1645 v = CAST(short, v);
1646 break;
1647 case FILE_DATE:
1648 case FILE_BEDATE:
1649 case FILE_LEDATE:
1650 case FILE_MEDATE:
1651 case FILE_LDATE:
1652 case FILE_BELDATE:
1653 case FILE_LELDATE:
1654 case FILE_MELDATE:
1655 case FILE_LONG:
1656 case FILE_BELONG:
1657 case FILE_LELONG:
1658 case FILE_MELONG:
1659 case FILE_FLOAT:
1660 case FILE_BEFLOAT:
1661 case FILE_LEFLOAT:
1662 case FILE_MSDOSDATE:
1663 case FILE_BEMSDOSDATE:
1664 case FILE_LEMSDOSDATE:
1665 case FILE_MSDOSTIME:
1666 case FILE_BEMSDOSTIME:
1667 case FILE_LEMSDOSTIME:
1668 v = CAST(int32_t, v);
1669 break;
1670 case FILE_QUAD:
1671 case FILE_BEQUAD:
1672 case FILE_LEQUAD:
1673 case FILE_QDATE:
1674 case FILE_QLDATE:
1675 case FILE_QWDATE:
1676 case FILE_BEQDATE:
1677 case FILE_BEQLDATE:
1678 case FILE_BEQWDATE:
1679 case FILE_LEQDATE:
1680 case FILE_LEQLDATE:
1681 case FILE_LEQWDATE:
1682 case FILE_DOUBLE:
1683 case FILE_BEDOUBLE:
1684 case FILE_LEDOUBLE:
1685 case FILE_OFFSET:
1686 case FILE_BEVARINT:
1687 case FILE_LEVARINT:
1688 v = CAST(int64_t, v);
1689 break;
1690 case FILE_STRING:
1691 case FILE_PSTRING:
1692 case FILE_BESTRING16:
1693 case FILE_LESTRING16:
1694 case FILE_REGEX:
1695 case FILE_SEARCH:
1696 case FILE_DEFAULT:
1697 case FILE_INDIRECT:
1698 case FILE_NAME:
1699 case FILE_USE:
1700 case FILE_CLEAR:
1701 case FILE_DER:
1702 case FILE_GUID:
1703 case FILE_OCTAL:
1704 break;
1705 default:
1706 if (ms->flags & MAGIC_CHECK)
1707 file_magwarn(ms, "cannot happen: m->type=%d\n",
1708 m->type);
1709 return FILE_BADSIZE;
1710 }
1711 }
1712 return v;
1713 }
1714
1715 private int
string_modifier_check(struct magic_set * ms,struct magic * m)1716 string_modifier_check(struct magic_set *ms, struct magic *m)
1717 {
1718 if ((ms->flags & MAGIC_CHECK) == 0)
1719 return 0;
1720
1721 if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1722 (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1723 file_magwarn(ms,
1724 "'/BHhLl' modifiers are only allowed for pascal strings\n");
1725 return -1;
1726 }
1727 switch (m->type) {
1728 case FILE_BESTRING16:
1729 case FILE_LESTRING16:
1730 if (m->str_flags != 0) {
1731 file_magwarn(ms,
1732 "no modifiers allowed for 16-bit strings\n");
1733 return -1;
1734 }
1735 break;
1736 case FILE_STRING:
1737 case FILE_PSTRING:
1738 if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1739 file_magwarn(ms,
1740 "'/%c' only allowed on regex and search\n",
1741 CHAR_REGEX_OFFSET_START);
1742 return -1;
1743 }
1744 break;
1745 case FILE_SEARCH:
1746 if (m->str_range == 0) {
1747 file_magwarn(ms,
1748 "missing range; defaulting to %d\n",
1749 STRING_DEFAULT_RANGE);
1750 m->str_range = STRING_DEFAULT_RANGE;
1751 return -1;
1752 }
1753 break;
1754 case FILE_REGEX:
1755 if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1756 file_magwarn(ms, "'/%c' not allowed on regex\n",
1757 CHAR_COMPACT_WHITESPACE);
1758 return -1;
1759 }
1760 if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1761 file_magwarn(ms, "'/%c' not allowed on regex\n",
1762 CHAR_COMPACT_OPTIONAL_WHITESPACE);
1763 return -1;
1764 }
1765 break;
1766 default:
1767 file_magwarn(ms, "coding error: m->type=%d\n",
1768 m->type);
1769 return -1;
1770 }
1771 return 0;
1772 }
1773
1774 private int
get_op(char c)1775 get_op(char c)
1776 {
1777 switch (c) {
1778 case '&':
1779 return FILE_OPAND;
1780 case '|':
1781 return FILE_OPOR;
1782 case '^':
1783 return FILE_OPXOR;
1784 case '+':
1785 return FILE_OPADD;
1786 case '-':
1787 return FILE_OPMINUS;
1788 case '*':
1789 return FILE_OPMULTIPLY;
1790 case '/':
1791 return FILE_OPDIVIDE;
1792 case '%':
1793 return FILE_OPMODULO;
1794 default:
1795 return -1;
1796 }
1797 }
1798
1799 #ifdef ENABLE_CONDITIONALS
1800 private int
get_cond(const char * l,const char ** t)1801 get_cond(const char *l, const char **t)
1802 {
1803 static const struct cond_tbl_s {
1804 char name[8];
1805 size_t len;
1806 int cond;
1807 } cond_tbl[] = {
1808 { "if", 2, COND_IF },
1809 { "elif", 4, COND_ELIF },
1810 { "else", 4, COND_ELSE },
1811 { "", 0, COND_NONE },
1812 };
1813 const struct cond_tbl_s *p;
1814
1815 for (p = cond_tbl; p->len; p++) {
1816 if (strncmp(l, p->name, p->len) == 0 &&
1817 isspace(CAST(unsigned char, l[p->len]))) {
1818 if (t)
1819 *t = l + p->len;
1820 break;
1821 }
1822 }
1823 return p->cond;
1824 }
1825
1826 private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1827 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1828 {
1829 int last_cond;
1830 last_cond = ms->c.li[cont_level].last_cond;
1831
1832 switch (cond) {
1833 case COND_IF:
1834 if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1835 if (ms->flags & MAGIC_CHECK)
1836 file_magwarn(ms, "syntax error: `if'");
1837 return -1;
1838 }
1839 last_cond = COND_IF;
1840 break;
1841
1842 case COND_ELIF:
1843 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1844 if (ms->flags & MAGIC_CHECK)
1845 file_magwarn(ms, "syntax error: `elif'");
1846 return -1;
1847 }
1848 last_cond = COND_ELIF;
1849 break;
1850
1851 case COND_ELSE:
1852 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1853 if (ms->flags & MAGIC_CHECK)
1854 file_magwarn(ms, "syntax error: `else'");
1855 return -1;
1856 }
1857 last_cond = COND_NONE;
1858 break;
1859
1860 case COND_NONE:
1861 last_cond = COND_NONE;
1862 break;
1863 }
1864
1865 ms->c.li[cont_level].last_cond = last_cond;
1866 return 0;
1867 }
1868 #endif /* ENABLE_CONDITIONALS */
1869
1870 private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1871 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1872 {
1873 const char *l = *lp;
1874
1875 while (!isspace(CAST(unsigned char, *++l)))
1876 switch (*l) {
1877 case CHAR_INDIRECT_RELATIVE:
1878 m->str_flags |= INDIRECT_RELATIVE;
1879 break;
1880 default:
1881 if (ms->flags & MAGIC_CHECK)
1882 file_magwarn(ms, "indirect modifier `%c' "
1883 "invalid", *l);
1884 *lp = l;
1885 return -1;
1886 }
1887 *lp = l;
1888 return 0;
1889 }
1890
1891 private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1892 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1893 int op)
1894 {
1895 const char *l = *lp;
1896 char *t;
1897 uint64_t val;
1898
1899 ++l;
1900 m->mask_op |= op;
1901 val = CAST(uint64_t, strtoull(l, &t, 0));
1902 l = t;
1903 m->num_mask = file_signextend(ms, m, val);
1904 eatsize(&l);
1905 *lp = l;
1906 }
1907
1908 private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1909 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1910 {
1911 const char *l = *lp;
1912 char *t;
1913 int have_range = 0;
1914
1915 while (!isspace(CAST(unsigned char, *++l))) {
1916 switch (*l) {
1917 case '0': case '1': case '2':
1918 case '3': case '4': case '5':
1919 case '6': case '7': case '8':
1920 case '9':
1921 if (have_range && (ms->flags & MAGIC_CHECK))
1922 file_magwarn(ms, "multiple ranges");
1923 have_range = 1;
1924 m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1925 if (m->str_range == 0)
1926 file_magwarn(ms, "zero range");
1927 l = t - 1;
1928 break;
1929 case CHAR_COMPACT_WHITESPACE:
1930 m->str_flags |= STRING_COMPACT_WHITESPACE;
1931 break;
1932 case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1933 m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1934 break;
1935 case CHAR_IGNORE_LOWERCASE:
1936 m->str_flags |= STRING_IGNORE_LOWERCASE;
1937 break;
1938 case CHAR_IGNORE_UPPERCASE:
1939 m->str_flags |= STRING_IGNORE_UPPERCASE;
1940 break;
1941 case CHAR_REGEX_OFFSET_START:
1942 m->str_flags |= REGEX_OFFSET_START;
1943 break;
1944 case CHAR_BINTEST:
1945 m->str_flags |= STRING_BINTEST;
1946 break;
1947 case CHAR_TEXTTEST:
1948 m->str_flags |= STRING_TEXTTEST;
1949 break;
1950 case CHAR_TRIM:
1951 m->str_flags |= STRING_TRIM;
1952 break;
1953 case CHAR_FULL_WORD:
1954 m->str_flags |= STRING_FULL_WORD;
1955 break;
1956 case CHAR_PSTRING_1_LE:
1957 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1958 if (m->type != FILE_PSTRING)
1959 goto bad;
1960 SET_LENGTH(PSTRING_1_LE);
1961 break;
1962 case CHAR_PSTRING_2_BE:
1963 if (m->type != FILE_PSTRING)
1964 goto bad;
1965 SET_LENGTH(PSTRING_2_BE);
1966 break;
1967 case CHAR_PSTRING_2_LE:
1968 if (m->type != FILE_PSTRING)
1969 goto bad;
1970 SET_LENGTH(PSTRING_2_LE);
1971 break;
1972 case CHAR_PSTRING_4_BE:
1973 if (m->type != FILE_PSTRING)
1974 goto bad;
1975 SET_LENGTH(PSTRING_4_BE);
1976 break;
1977 case CHAR_PSTRING_4_LE:
1978 switch (m->type) {
1979 case FILE_PSTRING:
1980 case FILE_REGEX:
1981 break;
1982 default:
1983 goto bad;
1984 }
1985 SET_LENGTH(PSTRING_4_LE);
1986 break;
1987 case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
1988 if (m->type != FILE_PSTRING)
1989 goto bad;
1990 m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
1991 break;
1992 default:
1993 bad:
1994 if (ms->flags & MAGIC_CHECK)
1995 file_magwarn(ms, "string modifier `%c' "
1996 "invalid", *l);
1997 goto out;
1998 }
1999 /* allow multiple '/' for readability */
2000 if (l[1] == '/' && !isspace(CAST(unsigned char, l[2])))
2001 l++;
2002 }
2003 if (string_modifier_check(ms, m) == -1)
2004 goto out;
2005 *lp = l;
2006 return 0;
2007 out:
2008 *lp = l;
2009 return -1;
2010 }
2011
2012 /*
2013 * parse one line from magic file, put into magic[index++] if valid
2014 */
2015 private int
parse(struct magic_set * ms,struct magic_entry * me,const char * line,size_t lineno,int action)2016 parse(struct magic_set *ms, struct magic_entry *me, const char *line,
2017 size_t lineno, int action)
2018 {
2019 #ifdef ENABLE_CONDITIONALS
2020 static uint32_t last_cont_level = 0;
2021 #endif
2022 size_t i;
2023 struct magic *m;
2024 const char *l = line;
2025 char *t;
2026 int op;
2027 uint32_t cont_level;
2028 int32_t diff;
2029
2030 cont_level = 0;
2031
2032 /*
2033 * Parse the offset.
2034 */
2035 while (*l == '>') {
2036 ++l; /* step over */
2037 cont_level++;
2038 }
2039 #ifdef ENABLE_CONDITIONALS
2040 if (cont_level == 0 || cont_level > last_cont_level)
2041 if (file_check_mem(ms, cont_level) == -1)
2042 return -1;
2043 last_cont_level = cont_level;
2044 #endif
2045 if (cont_level != 0) {
2046 if (me->mp == NULL) {
2047 file_magerror(ms, "No current entry for continuation");
2048 return -1;
2049 }
2050 if (me->cont_count == 0) {
2051 file_magerror(ms, "Continuations present with 0 count");
2052 return -1;
2053 }
2054 m = &me->mp[me->cont_count - 1];
2055 diff = CAST(int32_t, cont_level) - CAST(int32_t, m->cont_level);
2056 if (diff > 1)
2057 file_magwarn(ms, "New continuation level %u is more "
2058 "than one larger than current level %u", cont_level,
2059 m->cont_level);
2060 if (me->cont_count == me->max_count) {
2061 struct magic *nm;
2062 size_t cnt = me->max_count + ALLOC_CHUNK;
2063 if ((nm = CAST(struct magic *, realloc(me->mp,
2064 sizeof(*nm) * cnt))) == NULL) {
2065 file_oomem(ms, sizeof(*nm) * cnt);
2066 return -1;
2067 }
2068 me->mp = nm;
2069 me->max_count = CAST(uint32_t, cnt);
2070 }
2071 m = &me->mp[me->cont_count++];
2072 (void)memset(m, 0, sizeof(*m));
2073 m->cont_level = cont_level;
2074 } else {
2075 static const size_t len = sizeof(*m) * ALLOC_CHUNK;
2076 if (me->mp != NULL)
2077 return 1;
2078 if ((m = CAST(struct magic *, malloc(len))) == NULL) {
2079 file_oomem(ms, len);
2080 return -1;
2081 }
2082 me->mp = m;
2083 me->max_count = ALLOC_CHUNK;
2084 (void)memset(m, 0, sizeof(*m));
2085 m->factor_op = FILE_FACTOR_OP_NONE;
2086 m->cont_level = 0;
2087 me->cont_count = 1;
2088 }
2089 m->lineno = CAST(uint32_t, lineno);
2090
2091 if (*l == '&') { /* m->cont_level == 0 checked below. */
2092 ++l; /* step over */
2093 m->flag |= OFFADD;
2094 }
2095 if (*l == '(') {
2096 ++l; /* step over */
2097 m->flag |= INDIR;
2098 if (m->flag & OFFADD)
2099 m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
2100
2101 if (*l == '&') { /* m->cont_level == 0 checked below */
2102 ++l; /* step over */
2103 m->flag |= OFFADD;
2104 }
2105 }
2106 /* Indirect offsets are not valid at level 0. */
2107 if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) {
2108 if (ms->flags & MAGIC_CHECK)
2109 file_magwarn(ms, "relative offset at level 0");
2110 return -1;
2111 }
2112
2113 /* get offset, then skip over it */
2114 if (*l == '-') {
2115 ++l; /* step over */
2116 m->flag |= OFFNEGATIVE;
2117 }
2118 m->offset = CAST(int32_t, strtol(l, &t, 0));
2119 if (l == t) {
2120 if (ms->flags & MAGIC_CHECK)
2121 file_magwarn(ms, "offset `%s' invalid", l);
2122 return -1;
2123 }
2124
2125 l = t;
2126
2127 if (m->flag & INDIR) {
2128 m->in_type = FILE_LONG;
2129 m->in_offset = 0;
2130 m->in_op = 0;
2131 /*
2132 * read [.,lbs][+-]nnnnn)
2133 */
2134 if (*l == '.' || *l == ',') {
2135 if (*l == ',')
2136 m->in_op |= FILE_OPSIGNED;
2137 l++;
2138 switch (*l) {
2139 case 'l':
2140 m->in_type = FILE_LELONG;
2141 break;
2142 case 'L':
2143 m->in_type = FILE_BELONG;
2144 break;
2145 case 'm':
2146 m->in_type = FILE_MELONG;
2147 break;
2148 case 'h':
2149 case 's':
2150 m->in_type = FILE_LESHORT;
2151 break;
2152 case 'H':
2153 case 'S':
2154 m->in_type = FILE_BESHORT;
2155 break;
2156 case 'c':
2157 case 'b':
2158 case 'C':
2159 case 'B':
2160 m->in_type = FILE_BYTE;
2161 break;
2162 case 'e':
2163 case 'f':
2164 case 'g':
2165 m->in_type = FILE_LEDOUBLE;
2166 break;
2167 case 'E':
2168 case 'F':
2169 case 'G':
2170 m->in_type = FILE_BEDOUBLE;
2171 break;
2172 case 'i':
2173 m->in_type = FILE_LEID3;
2174 break;
2175 case 'I':
2176 m->in_type = FILE_BEID3;
2177 break;
2178 case 'o':
2179 m->in_type = FILE_OCTAL;
2180 break;
2181 case 'q':
2182 m->in_type = FILE_LEQUAD;
2183 break;
2184 case 'Q':
2185 m->in_type = FILE_BEQUAD;
2186 break;
2187 default:
2188 if (ms->flags & MAGIC_CHECK)
2189 file_magwarn(ms,
2190 "indirect offset type `%c' invalid",
2191 *l);
2192 return -1;
2193 }
2194 l++;
2195 }
2196
2197 if (*l == '~') {
2198 m->in_op |= FILE_OPINVERSE;
2199 l++;
2200 }
2201 if ((op = get_op(*l)) != -1) {
2202 m->in_op |= op;
2203 l++;
2204 }
2205 if (*l == '(') {
2206 m->in_op |= FILE_OPINDIRECT;
2207 l++;
2208 }
2209 if (isdigit(CAST(unsigned char, *l)) || *l == '-') {
2210 m->in_offset = CAST(int32_t, strtol(l, &t, 0));
2211 if (l == t) {
2212 if (ms->flags & MAGIC_CHECK)
2213 file_magwarn(ms,
2214 "in_offset `%s' invalid", l);
2215 return -1;
2216 }
2217 l = t;
2218 }
2219 if (*l++ != ')' ||
2220 ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) {
2221 if (ms->flags & MAGIC_CHECK)
2222 file_magwarn(ms,
2223 "missing ')' in indirect offset");
2224 return -1;
2225 }
2226 }
2227 EATAB;
2228
2229 #ifdef ENABLE_CONDITIONALS
2230 m->cond = get_cond(l, &l);
2231 if (check_cond(ms, m->cond, cont_level) == -1)
2232 return -1;
2233
2234 EATAB;
2235 #endif
2236
2237 /*
2238 * Parse the type.
2239 */
2240 if (*l == 'u') {
2241 /*
2242 * Try it as a keyword type prefixed by "u"; match what
2243 * follows the "u". If that fails, try it as an SUS
2244 * integer type.
2245 */
2246 m->type = get_type(type_tbl, l + 1, &l);
2247 if (m->type == FILE_INVALID) {
2248 /*
2249 * Not a keyword type; parse it as an SUS type,
2250 * 'u' possibly followed by a number or C/S/L.
2251 */
2252 m->type = get_standard_integer_type(l, &l);
2253 }
2254 /* It's unsigned. */
2255 if (m->type != FILE_INVALID)
2256 m->flag |= UNSIGNED;
2257 } else {
2258 /*
2259 * Try it as a keyword type. If that fails, try it as
2260 * an SUS integer type if it begins with "d" or as an
2261 * SUS string type if it begins with "s". In any case,
2262 * it's not unsigned.
2263 */
2264 m->type = get_type(type_tbl, l, &l);
2265 if (m->type == FILE_INVALID) {
2266 /*
2267 * Not a keyword type; parse it as an SUS type,
2268 * either 'd' possibly followed by a number or
2269 * C/S/L, or just 's'.
2270 */
2271 if (*l == 'd')
2272 m->type = get_standard_integer_type(l, &l);
2273 else if (*l == 's'
2274 && !isalpha(CAST(unsigned char, l[1]))) {
2275 m->type = FILE_STRING;
2276 ++l;
2277 }
2278 }
2279 }
2280
2281 if (m->type == FILE_INVALID) {
2282 /* Not found - try it as a special keyword. */
2283 m->type = get_type(special_tbl, l, &l);
2284 }
2285
2286 if (m->type == FILE_INVALID) {
2287 if (ms->flags & MAGIC_CHECK)
2288 file_magwarn(ms, "type `%s' invalid", l);
2289 return -1;
2290 }
2291
2292 if (m->type == FILE_NAME && cont_level != 0) {
2293 if (ms->flags & MAGIC_CHECK)
2294 file_magwarn(ms, "`name%s' entries can only be "
2295 "declared at top level", l);
2296 return -1;
2297 }
2298
2299 /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2300 /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2301
2302 m->mask_op = 0;
2303 if (*l == '~') {
2304 if (!IS_STRING(m->type))
2305 m->mask_op |= FILE_OPINVERSE;
2306 else if (ms->flags & MAGIC_CHECK)
2307 file_magwarn(ms, "'~' invalid for string types");
2308 ++l;
2309 }
2310 m->str_range = 0;
2311 m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2312 if ((op = get_op(*l)) != -1) {
2313 if (IS_STRING(m->type)) {
2314 int r;
2315
2316 if (op != FILE_OPDIVIDE) {
2317 if (ms->flags & MAGIC_CHECK)
2318 file_magwarn(ms,
2319 "invalid string/indirect op: "
2320 "`%c'", *t);
2321 return -1;
2322 }
2323
2324 if (m->type == FILE_INDIRECT)
2325 r = parse_indirect_modifier(ms, m, &l);
2326 else
2327 r = parse_string_modifier(ms, m, &l);
2328 if (r == -1)
2329 return -1;
2330 } else
2331 parse_op_modifier(ms, m, &l, op);
2332 }
2333
2334 /*
2335 * We used to set mask to all 1's here, instead let's just not do
2336 * anything if mask = 0 (unless you have a better idea)
2337 */
2338 EATAB;
2339
2340 switch (*l) {
2341 case '>':
2342 case '<':
2343 m->reln = *l;
2344 ++l;
2345 if (*l == '=') {
2346 if (ms->flags & MAGIC_CHECK) {
2347 file_magwarn(ms, "%c= not supported",
2348 m->reln);
2349 return -1;
2350 }
2351 ++l;
2352 }
2353 break;
2354 /* Old-style anding: "0 byte &0x80 dynamically linked" */
2355 case '&':
2356 case '^':
2357 case '=':
2358 m->reln = *l;
2359 ++l;
2360 if (*l == '=') {
2361 /* HP compat: ignore &= etc. */
2362 ++l;
2363 }
2364 break;
2365 case '!':
2366 m->reln = *l;
2367 ++l;
2368 break;
2369 default:
2370 m->reln = '='; /* the default relation */
2371 if (*l == 'x' && ((isascii(CAST(unsigned char, l[1])) &&
2372 isspace(CAST(unsigned char, l[1]))) || !l[1])) {
2373 m->reln = *l;
2374 ++l;
2375 }
2376 break;
2377 }
2378 /*
2379 * Grab the value part, except for an 'x' reln.
2380 */
2381 if (m->reln != 'x' && getvalue(ms, m, &l, action))
2382 return -1;
2383
2384 /*
2385 * TODO finish this macro and start using it!
2386 * #define offsetcheck {if (offset > ms->bytes_max -1)
2387 * magwarn("offset too big"); }
2388 */
2389
2390 /*
2391 * Now get last part - the description
2392 */
2393 EATAB;
2394 if (l[0] == '\b') {
2395 ++l;
2396 m->flag |= NOSPACE;
2397 } else if ((l[0] == '\\') && (l[1] == 'b')) {
2398 ++l;
2399 ++l;
2400 m->flag |= NOSPACE;
2401 }
2402 for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); )
2403 continue;
2404 if (i == sizeof(m->desc)) {
2405 m->desc[sizeof(m->desc) - 1] = '\0';
2406 if (ms->flags & MAGIC_CHECK)
2407 file_magwarn(ms, "description `%s' truncated", m->desc);
2408 }
2409
2410 /*
2411 * We only do this check while compiling, or if any of the magic
2412 * files were not compiled.
2413 */
2414 if (ms->flags & MAGIC_CHECK) {
2415 if (check_format(ms, m) == -1)
2416 return -1;
2417 }
2418 #ifndef COMPILE_ONLY
2419 if (action == FILE_CHECK) {
2420 file_mdump(m);
2421 }
2422 #endif
2423 m->mimetype[0] = '\0'; /* initialise MIME type to none */
2424 return 0;
2425 }
2426
2427 /*
2428 * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2429 * if valid
2430 */
2431 /*ARGSUSED*/
2432 private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2433 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line,
2434 size_t len __attribute__((__unused__)))
2435 {
2436 const char *l = line;
2437 char *el;
2438 unsigned long factor;
2439 struct magic *m = &me->mp[0];
2440
2441 if (m->factor_op != FILE_FACTOR_OP_NONE) {
2442 file_magwarn(ms,
2443 "Current entry already has a strength type: %c %d",
2444 m->factor_op, m->factor);
2445 return -1;
2446 }
2447 if (m->type == FILE_NAME) {
2448 file_magwarn(ms, "%s: Strength setting is not supported in "
2449 "\"name\" magic entries", m->value.s);
2450 return -1;
2451 }
2452 EATAB;
2453 switch (*l) {
2454 case FILE_FACTOR_OP_NONE:
2455 case FILE_FACTOR_OP_PLUS:
2456 case FILE_FACTOR_OP_MINUS:
2457 case FILE_FACTOR_OP_TIMES:
2458 case FILE_FACTOR_OP_DIV:
2459 m->factor_op = *l++;
2460 break;
2461 default:
2462 file_magwarn(ms, "Unknown factor op `%c'", *l);
2463 return -1;
2464 }
2465 EATAB;
2466 factor = strtoul(l, &el, 0);
2467 if (factor > 255) {
2468 file_magwarn(ms, "Too large factor `%lu'", factor);
2469 goto out;
2470 }
2471 if (*el && !isspace(CAST(unsigned char, *el))) {
2472 file_magwarn(ms, "Bad factor `%s'", l);
2473 goto out;
2474 }
2475 m->factor = CAST(uint8_t, factor);
2476 if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2477 file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2478 m->factor_op, m->factor);
2479 goto out;
2480 }
2481 return 0;
2482 out:
2483 m->factor_op = FILE_FACTOR_OP_NONE;
2484 m->factor = 0;
2485 return -1;
2486 }
2487
2488 private int
goodchar(unsigned char x,const char * extra)2489 goodchar(unsigned char x, const char *extra)
2490 {
2491 return (isascii(x) && isalnum(x)) || strchr(extra, x);
2492 }
2493
2494 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)2495 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2496 size_t llen, off_t off, size_t len, const char *name, const char *extra,
2497 int nt)
2498 {
2499 size_t i;
2500 const char *l = line;
2501 struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2502 char *buf = CAST(char *, CAST(void *, m)) + off;
2503
2504 if (buf[0] != '\0') {
2505 len = nt ? strlen(buf) : len;
2506 file_magwarn(ms, "Current entry already has a %s type "
2507 "`%.*s', new type `%s'", name, CAST(int, len), buf, l);
2508 return -1;
2509 }
2510
2511 if (*m->desc == '\0') {
2512 file_magwarn(ms, "Current entry does not yet have a "
2513 "description for adding a %s type", name);
2514 return -1;
2515 }
2516
2517 EATAB;
2518 for (i = 0; *l && i < llen && i < len && goodchar(*l, extra);
2519 buf[i++] = *l++)
2520 continue;
2521
2522 if (i == len && *l) {
2523 if (nt)
2524 buf[len - 1] = '\0';
2525 if (ms->flags & MAGIC_CHECK)
2526 file_magwarn(ms, "%s type `%s' truncated %"
2527 SIZE_T_FORMAT "u", name, line, i);
2528 } else {
2529 if (!isspace(CAST(unsigned char, *l)) && !goodchar(*l, extra))
2530 file_magwarn(ms, "%s type `%s' has bad char '%c'",
2531 name, line, *l);
2532 if (nt)
2533 buf[i] = '\0';
2534 }
2535
2536 if (i > 0)
2537 return 0;
2538
2539 file_magerror(ms, "Bad magic entry '%s'", line);
2540 return -1;
2541 }
2542
2543 /*
2544 * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2545 * magic[index - 1]
2546 */
2547 private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2548 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line,
2549 size_t len)
2550 {
2551 return parse_extra(ms, me, line, len,
2552 CAST(off_t, offsetof(struct magic, apple)),
2553 sizeof(me->mp[0].apple), "APPLE", "!+-./?", 0);
2554 }
2555
2556 /*
2557 * Parse a comma-separated list of extensions
2558 */
2559 private int
parse_ext(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2560 parse_ext(struct magic_set *ms, struct magic_entry *me, const char *line,
2561 size_t len)
2562 {
2563 return parse_extra(ms, me, line, len,
2564 CAST(off_t, offsetof(struct magic, ext)),
2565 sizeof(me->mp[0].ext), "EXTENSION", ",!+-/@?_$&", 0); /* & for b&w */
2566 }
2567
2568 /*
2569 * parse a MIME annotation line from magic file, put into magic[index - 1]
2570 * if valid
2571 */
2572 private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2573 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line,
2574 size_t len)
2575 {
2576 return parse_extra(ms, me, line, len,
2577 CAST(off_t, offsetof(struct magic, mimetype)),
2578 sizeof(me->mp[0].mimetype), "MIME", "+-/.$?:{}", 1);
2579 }
2580
2581 private int
check_format_type(const char * ptr,int type,const char ** estr)2582 check_format_type(const char *ptr, int type, const char **estr)
2583 {
2584 int quad = 0, h;
2585 size_t len, cnt;
2586 if (*ptr == '\0') {
2587 /* Missing format string; bad */
2588 *estr = "missing format spec";
2589 return -1;
2590 }
2591
2592 switch (file_formats[type]) {
2593 case FILE_FMT_QUAD:
2594 quad = 1;
2595 /*FALLTHROUGH*/
2596 case FILE_FMT_NUM:
2597 if (quad == 0) {
2598 switch (type) {
2599 case FILE_BYTE:
2600 h = 2;
2601 break;
2602 case FILE_SHORT:
2603 case FILE_BESHORT:
2604 case FILE_LESHORT:
2605 h = 1;
2606 break;
2607 case FILE_LONG:
2608 case FILE_BELONG:
2609 case FILE_LELONG:
2610 case FILE_MELONG:
2611 case FILE_LEID3:
2612 case FILE_BEID3:
2613 case FILE_INDIRECT:
2614 h = 0;
2615 break;
2616 default:
2617 fprintf(stderr, "Bad number format %d", type);
2618 abort();
2619 }
2620 } else
2621 h = 0;
2622 while (*ptr && strchr("-.#", *ptr) != NULL)
2623 ptr++;
2624 #define CHECKLEN() do { \
2625 for (len = cnt = 0; isdigit(CAST(unsigned char, *ptr)); ptr++, cnt++) \
2626 len = len * 10 + (*ptr - '0'); \
2627 if (cnt > 5 || len > 1024) \
2628 goto toolong; \
2629 } while (/*CONSTCOND*/0)
2630
2631 CHECKLEN();
2632 if (*ptr == '.')
2633 ptr++;
2634 CHECKLEN();
2635 if (quad) {
2636 if (*ptr++ != 'l')
2637 goto invalid;
2638 if (*ptr++ != 'l')
2639 goto invalid;
2640 }
2641
2642 switch (*ptr++) {
2643 #ifdef STRICT_FORMAT /* "long" formats are int formats for us */
2644 /* so don't accept the 'l' modifier */
2645 case 'l':
2646 switch (*ptr++) {
2647 case 'i':
2648 case 'd':
2649 case 'u':
2650 case 'o':
2651 case 'x':
2652 case 'X':
2653 if (h == 0)
2654 return 0;
2655 /*FALLTHROUGH*/
2656 default:
2657 goto invalid;
2658 }
2659
2660 /*
2661 * Don't accept h and hh modifiers. They make writing
2662 * magic entries more complicated, for very little benefit
2663 */
2664 case 'h':
2665 if (h-- <= 0)
2666 goto invalid;
2667 switch (*ptr++) {
2668 case 'h':
2669 if (h-- <= 0)
2670 goto invalid;
2671 switch (*ptr++) {
2672 case 'i':
2673 case 'd':
2674 case 'u':
2675 case 'o':
2676 case 'x':
2677 case 'X':
2678 return 0;
2679 default:
2680 goto invalid;
2681 }
2682 case 'i':
2683 case 'd':
2684 case 'u':
2685 case 'o':
2686 case 'x':
2687 case 'X':
2688 if (h == 0)
2689 return 0;
2690 /*FALLTHROUGH*/
2691 default:
2692 goto invalid;
2693 }
2694 #endif
2695 case 'c':
2696 if (h == 2)
2697 return 0;
2698 goto invalid;
2699 case 'i':
2700 case 'd':
2701 case 'u':
2702 case 'o':
2703 case 'x':
2704 case 'X':
2705 #ifdef STRICT_FORMAT
2706 if (h == 0)
2707 return 0;
2708 /*FALLTHROUGH*/
2709 #else
2710 return 0;
2711 #endif
2712 default:
2713 goto invalid;
2714 }
2715
2716 case FILE_FMT_FLOAT:
2717 case FILE_FMT_DOUBLE:
2718 if (*ptr == '-')
2719 ptr++;
2720 if (*ptr == '.')
2721 ptr++;
2722 CHECKLEN();
2723 if (*ptr == '.')
2724 ptr++;
2725 CHECKLEN();
2726 switch (*ptr++) {
2727 case 'e':
2728 case 'E':
2729 case 'f':
2730 case 'F':
2731 case 'g':
2732 case 'G':
2733 return 0;
2734
2735 default:
2736 goto invalid;
2737 }
2738
2739
2740 case FILE_FMT_STR:
2741 if (*ptr == '-')
2742 ptr++;
2743 while (isdigit(CAST(unsigned char, *ptr)))
2744 ptr++;
2745 if (*ptr == '.') {
2746 ptr++;
2747 while (isdigit(CAST(unsigned char , *ptr)))
2748 ptr++;
2749 }
2750
2751 switch (*ptr++) {
2752 case 's':
2753 return 0;
2754 default:
2755 goto invalid;
2756 }
2757
2758 default:
2759 /* internal error */
2760 fprintf(stderr, "Bad file format %d", type);
2761 abort();
2762 }
2763 invalid:
2764 *estr = "not valid";
2765 toolong:
2766 *estr = "too long";
2767 return -1;
2768 }
2769
2770 /*
2771 * Check that the optional printf format in description matches
2772 * the type of the magic.
2773 */
2774 private int
check_format(struct magic_set * ms,struct magic * m)2775 check_format(struct magic_set *ms, struct magic *m)
2776 {
2777 char *ptr;
2778 const char *estr;
2779
2780 for (ptr = m->desc; *ptr; ptr++)
2781 if (*ptr == '%')
2782 break;
2783 if (*ptr == '\0') {
2784 /* No format string; ok */
2785 return 1;
2786 }
2787
2788 assert(file_nformats == file_nnames);
2789
2790 if (m->type >= file_nformats) {
2791 file_magwarn(ms, "Internal error inconsistency between "
2792 "m->type and format strings");
2793 return -1;
2794 }
2795 if (file_formats[m->type] == FILE_FMT_NONE) {
2796 file_magwarn(ms, "No format string for `%s' with description "
2797 "`%s'", m->desc, file_names[m->type]);
2798 return -1;
2799 }
2800
2801 ptr++;
2802 if (check_format_type(ptr, m->type, &estr) == -1) {
2803 /*
2804 * TODO: this error message is unhelpful if the format
2805 * string is not one character long
2806 */
2807 file_magwarn(ms, "Printf format is %s for type "
2808 "`%s' in description `%s'", estr,
2809 file_names[m->type], m->desc);
2810 return -1;
2811 }
2812
2813 for (; *ptr; ptr++) {
2814 if (*ptr == '%') {
2815 file_magwarn(ms,
2816 "Too many format strings (should have at most one) "
2817 "for `%s' with description `%s'",
2818 file_names[m->type], m->desc);
2819 return -1;
2820 }
2821 }
2822 return 0;
2823 }
2824
2825 /*
2826 * Read a numeric value from a pointer, into the value union of a magic
2827 * pointer, according to the magic type. Update the string pointer to point
2828 * just after the number read. Return 0 for success, non-zero for failure.
2829 */
2830 private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2831 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2832 {
2833 char *ep;
2834 uint64_t ull;
2835
2836 switch (m->type) {
2837 case FILE_BESTRING16:
2838 case FILE_LESTRING16:
2839 case FILE_STRING:
2840 case FILE_PSTRING:
2841 case FILE_REGEX:
2842 case FILE_SEARCH:
2843 case FILE_NAME:
2844 case FILE_USE:
2845 case FILE_DER:
2846 case FILE_OCTAL:
2847 *p = getstr(ms, m, *p, action == FILE_COMPILE);
2848 if (*p == NULL) {
2849 if (ms->flags & MAGIC_CHECK)
2850 file_magwarn(ms, "cannot get string from `%s'",
2851 m->value.s);
2852 return -1;
2853 }
2854 if (m->type == FILE_REGEX) {
2855 file_regex_t rx;
2856 int rc = file_regcomp(ms, &rx, m->value.s,
2857 REG_EXTENDED);
2858 if (rc == 0) {
2859 file_regfree(&rx);
2860 }
2861 return rc ? -1 : 0;
2862 }
2863 return 0;
2864 default:
2865 if (m->reln == 'x')
2866 return 0;
2867 break;
2868 }
2869
2870 switch (m->type) {
2871 case FILE_FLOAT:
2872 case FILE_BEFLOAT:
2873 case FILE_LEFLOAT:
2874 errno = 0;
2875 #ifdef HAVE_STRTOF
2876 m->value.f = strtof(*p, &ep);
2877 #else
2878 m->value.f = (float)strtod(*p, &ep);
2879 #endif
2880 if (errno == 0)
2881 *p = ep;
2882 return 0;
2883 case FILE_DOUBLE:
2884 case FILE_BEDOUBLE:
2885 case FILE_LEDOUBLE:
2886 errno = 0;
2887 m->value.d = strtod(*p, &ep);
2888 if (errno == 0)
2889 *p = ep;
2890 return 0;
2891 case FILE_GUID:
2892 if (file_parse_guid(*p, m->value.guid) == -1)
2893 return -1;
2894 *p += FILE_GUID_SIZE - 1;
2895 return 0;
2896 default:
2897 errno = 0;
2898 ull = CAST(uint64_t, strtoull(*p, &ep, 0));
2899 m->value.q = file_signextend(ms, m, ull);
2900 if (*p == ep) {
2901 file_magwarn(ms, "Unparsable number `%s'", *p);
2902 } else {
2903 size_t ts = typesize(m->type);
2904 uint64_t x;
2905 const char *q;
2906
2907 if (ts == FILE_BADSIZE) {
2908 file_magwarn(ms,
2909 "Expected numeric type got `%s'",
2910 type_tbl[m->type].name);
2911 }
2912 for (q = *p; isspace(CAST(unsigned char, *q)); q++)
2913 continue;
2914 if (*q == '-')
2915 ull = -CAST(int64_t, ull);
2916 switch (ts) {
2917 case 1:
2918 x = CAST(uint64_t, ull & ~0xffULL);
2919 break;
2920 case 2:
2921 x = CAST(uint64_t, ull & ~0xffffULL);
2922 break;
2923 case 4:
2924 x = CAST(uint64_t, ull & ~0xffffffffULL);
2925 break;
2926 case 8:
2927 x = 0;
2928 break;
2929 default:
2930 fprintf(stderr, "Bad width %zu", ts);
2931 abort();
2932 }
2933 if (x) {
2934 file_magwarn(ms, "Overflow for numeric"
2935 " type `%s' value %#" PRIx64,
2936 type_tbl[m->type].name, ull);
2937 }
2938 }
2939 if (errno == 0) {
2940 *p = ep;
2941 eatsize(p);
2942 }
2943 return 0;
2944 }
2945 }
2946
2947 /*
2948 * Convert a string containing C character escapes. Stop at an unescaped
2949 * space or tab.
2950 * Copy the converted version to "m->value.s", and the length in m->vallen.
2951 * Return updated scan pointer as function result. Warn if set.
2952 */
2953 private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)2954 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
2955 {
2956 const char *origs = s;
2957 char *p = m->value.s;
2958 size_t plen = sizeof(m->value.s);
2959 char *origp = p;
2960 char *pmax = p + plen - 1;
2961 int c;
2962 int val;
2963 size_t bracket_nesting = 0;
2964
2965 while ((c = *s++) != '\0') {
2966 if (isspace(CAST(unsigned char, c)))
2967 break;
2968 if (p >= pmax) {
2969 file_error(ms, 0, "string too long: `%s'", origs);
2970 return NULL;
2971 }
2972 if (c != '\\') {
2973 if (c == '[') {
2974 bracket_nesting++;
2975 }
2976 if (c == ']' && bracket_nesting > 0) {
2977 bracket_nesting--;
2978 }
2979 *p++ = CAST(char, c);
2980 continue;
2981 }
2982 switch(c = *s++) {
2983
2984 case '\0':
2985 if (warn)
2986 file_magwarn(ms, "incomplete escape");
2987 s--;
2988 goto out;
2989 case '.':
2990 if (m->type == FILE_REGEX &&
2991 bracket_nesting == 0 && warn) {
2992 file_magwarn(ms, "escaped dot ('.') found, "
2993 "use \\\\. instead");
2994 }
2995 warn = 0; /* already did */
2996 /*FALLTHROUGH*/
2997 case '\t':
2998 if (warn) {
2999 file_magwarn(ms,
3000 "escaped tab found, use \\\\t instead");
3001 warn = 0; /* already did */
3002 }
3003 /*FALLTHROUGH*/
3004 default:
3005 if (warn) {
3006 if (isprint(CAST(unsigned char, c))) {
3007 /* Allow escaping of
3008 * ``relations'' */
3009 if (strchr("<>&^=!", c) == NULL
3010 && (m->type != FILE_REGEX ||
3011 strchr("[]().*?^$|{}", c)
3012 == NULL)) {
3013 file_magwarn(ms, "no "
3014 "need to escape "
3015 "`%c'", c);
3016 }
3017 } else {
3018 file_magwarn(ms,
3019 "unknown escape sequence: "
3020 "\\%03o", c);
3021 }
3022 }
3023 /*FALLTHROUGH*/
3024 /* space, perhaps force people to use \040? */
3025 case ' ':
3026 #if 0
3027 /*
3028 * Other things people escape, but shouldn't need to,
3029 * so we disallow them
3030 */
3031 case '\'':
3032 case '"':
3033 case '?':
3034 #endif
3035 /* Relations */
3036 case '>':
3037 case '<':
3038 case '&':
3039 case '^':
3040 case '=':
3041 case '!':
3042 /* and backslash itself */
3043 case '\\':
3044 *p++ = CAST(char, c);
3045 break;
3046
3047 case 'a':
3048 *p++ = '\a';
3049 break;
3050
3051 case 'b':
3052 *p++ = '\b';
3053 break;
3054
3055 case 'f':
3056 *p++ = '\f';
3057 break;
3058
3059 case 'n':
3060 *p++ = '\n';
3061 break;
3062
3063 case 'r':
3064 *p++ = '\r';
3065 break;
3066
3067 case 't':
3068 *p++ = '\t';
3069 break;
3070
3071 case 'v':
3072 *p++ = '\v';
3073 break;
3074
3075 /* \ and up to 3 octal digits */
3076 case '0':
3077 case '1':
3078 case '2':
3079 case '3':
3080 case '4':
3081 case '5':
3082 case '6':
3083 case '7':
3084 val = c - '0';
3085 c = *s++; /* try for 2 */
3086 if (c >= '0' && c <= '7') {
3087 val = (val << 3) | (c - '0');
3088 c = *s++; /* try for 3 */
3089 if (c >= '0' && c <= '7')
3090 val = (val << 3) | (c-'0');
3091 else
3092 --s;
3093 }
3094 else
3095 --s;
3096 *p++ = CAST(char, val);
3097 break;
3098
3099 /* \x and up to 2 hex digits */
3100 case 'x':
3101 val = 'x'; /* Default if no digits */
3102 c = hextoint(*s++); /* Get next char */
3103 if (c >= 0) {
3104 val = c;
3105 c = hextoint(*s++);
3106 if (c >= 0)
3107 val = (val << 4) + c;
3108 else
3109 --s;
3110 } else
3111 --s;
3112 *p++ = CAST(char, val);
3113 break;
3114 }
3115 }
3116 --s;
3117 out:
3118 *p = '\0';
3119 m->vallen = CAST(unsigned char, (p - origp));
3120 if (m->type == FILE_PSTRING) {
3121 size_t l = file_pstring_length_size(ms, m);
3122 if (l == FILE_BADSIZE)
3123 return NULL;
3124 m->vallen += CAST(unsigned char, l);
3125 }
3126 return s;
3127 }
3128
3129
3130 /* Single hex char to int; -1 if not a hex char. */
3131 private int
hextoint(int c)3132 hextoint(int c)
3133 {
3134 if (!isascii(CAST(unsigned char, c)))
3135 return -1;
3136 if (isdigit(CAST(unsigned char, c)))
3137 return c - '0';
3138 if ((c >= 'a') && (c <= 'f'))
3139 return c + 10 - 'a';
3140 if (( c>= 'A') && (c <= 'F'))
3141 return c + 10 - 'A';
3142 return -1;
3143 }
3144
3145
3146 /*
3147 * Print a string containing C character escapes.
3148 */
3149 protected void
file_showstr(FILE * fp,const char * s,size_t len)3150 file_showstr(FILE *fp, const char *s, size_t len)
3151 {
3152 char c;
3153
3154 for (;;) {
3155 if (len == FILE_BADSIZE) {
3156 c = *s++;
3157 if (c == '\0')
3158 break;
3159 }
3160 else {
3161 if (len-- == 0)
3162 break;
3163 c = *s++;
3164 }
3165 if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */
3166 (void) fputc(c, fp);
3167 else {
3168 (void) fputc('\\', fp);
3169 switch (c) {
3170 case '\a':
3171 (void) fputc('a', fp);
3172 break;
3173
3174 case '\b':
3175 (void) fputc('b', fp);
3176 break;
3177
3178 case '\f':
3179 (void) fputc('f', fp);
3180 break;
3181
3182 case '\n':
3183 (void) fputc('n', fp);
3184 break;
3185
3186 case '\r':
3187 (void) fputc('r', fp);
3188 break;
3189
3190 case '\t':
3191 (void) fputc('t', fp);
3192 break;
3193
3194 case '\v':
3195 (void) fputc('v', fp);
3196 break;
3197
3198 default:
3199 (void) fprintf(fp, "%.3o", c & 0377);
3200 break;
3201 }
3202 }
3203 }
3204 }
3205
3206 /*
3207 * eatsize(): Eat the size spec from a number [eg. 10UL]
3208 */
3209 private void
eatsize(const char ** p)3210 eatsize(const char **p)
3211 {
3212 const char *l = *p;
3213
3214 if (LOWCASE(*l) == 'u')
3215 l++;
3216
3217 switch (LOWCASE(*l)) {
3218 case 'l': /* long */
3219 case 's': /* short */
3220 case 'h': /* short */
3221 case 'b': /* char/byte */
3222 case 'c': /* char/byte */
3223 l++;
3224 /*FALLTHROUGH*/
3225 default:
3226 break;
3227 }
3228
3229 *p = l;
3230 }
3231
3232 /*
3233 * handle a buffer containing a compiled file.
3234 */
3235 private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)3236 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
3237 {
3238 struct magic_map *map;
3239
3240 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3241 file_oomem(ms, sizeof(*map));
3242 return NULL;
3243 }
3244 map->len = len;
3245 map->p = buf;
3246 map->type = MAP_TYPE_USER;
3247 if (check_buffer(ms, map, "buffer") != 0) {
3248 apprentice_unmap(map);
3249 return NULL;
3250 }
3251 return map;
3252 }
3253
3254 /*
3255 * handle a compiled file.
3256 */
3257
3258 private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)3259 apprentice_map(struct magic_set *ms, const char *fn)
3260 {
3261 int fd;
3262 struct stat st;
3263 char *dbname = NULL;
3264 struct magic_map *map;
3265 struct magic_map *rv = NULL;
3266
3267 fd = -1;
3268 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3269 file_oomem(ms, sizeof(*map));
3270 goto error;
3271 }
3272 map->type = MAP_TYPE_USER; /* unspecified */
3273
3274 dbname = mkdbname(ms, fn, 0);
3275 if (dbname == NULL)
3276 goto error;
3277
3278 if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
3279 goto error;
3280
3281 if (fstat(fd, &st) == -1) {
3282 file_error(ms, errno, "cannot stat `%s'", dbname);
3283 goto error;
3284 }
3285 if (st.st_size < 8 || st.st_size > maxoff_t()) {
3286 file_error(ms, 0, "file `%s' is too %s", dbname,
3287 st.st_size < 8 ? "small" : "large");
3288 goto error;
3289 }
3290
3291 map->len = CAST(size_t, st.st_size);
3292 #ifdef QUICK
3293 map->type = MAP_TYPE_MMAP;
3294 if ((map->p = mmap(0, CAST(size_t, st.st_size), PROT_READ|PROT_WRITE,
3295 MAP_PRIVATE|MAP_FILE, fd, CAST(off_t, 0))) == MAP_FAILED) {
3296 file_error(ms, errno, "cannot map `%s'", dbname);
3297 goto error;
3298 }
3299 #else
3300 map->type = MAP_TYPE_MALLOC;
3301 if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
3302 file_oomem(ms, map->len);
3303 goto error;
3304 }
3305 if (read(fd, map->p, map->len) != (ssize_t)map->len) {
3306 file_badread(ms);
3307 goto error;
3308 }
3309 #endif
3310 (void)close(fd);
3311 fd = -1;
3312
3313 if (check_buffer(ms, map, dbname) != 0) {
3314 goto error;
3315 }
3316 #ifdef QUICK
3317 if (mprotect(map->p, CAST(size_t, st.st_size), PROT_READ) == -1) {
3318 file_error(ms, errno, "cannot mprotect `%s'", dbname);
3319 goto error;
3320 }
3321 #endif
3322
3323 free(dbname);
3324 return map;
3325
3326 error:
3327 if (fd != -1)
3328 (void)close(fd);
3329 apprentice_unmap(map);
3330 free(dbname);
3331 return rv;
3332 }
3333
3334 private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)3335 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
3336 {
3337 uint32_t *ptr;
3338 uint32_t entries, nentries;
3339 uint32_t version;
3340 int i, needsbyteswap;
3341
3342 ptr = CAST(uint32_t *, map->p);
3343 if (*ptr != MAGICNO) {
3344 if (swap4(*ptr) != MAGICNO) {
3345 file_error(ms, 0, "bad magic in `%s'", dbname);
3346 return -1;
3347 }
3348 needsbyteswap = 1;
3349 } else
3350 needsbyteswap = 0;
3351 if (needsbyteswap)
3352 version = swap4(ptr[1]);
3353 else
3354 version = ptr[1];
3355 if (version != VERSIONNO) {
3356 file_error(ms, 0, "File %s supports only version %d magic "
3357 "files. `%s' is version %d", VERSION,
3358 VERSIONNO, dbname, version);
3359 return -1;
3360 }
3361 entries = CAST(uint32_t, map->len / sizeof(struct magic));
3362 if ((entries * sizeof(struct magic)) != map->len) {
3363 file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
3364 "a multiple of %" SIZE_T_FORMAT "u",
3365 dbname, map->len, sizeof(struct magic));
3366 return -1;
3367 }
3368 map->magic[0] = CAST(struct magic *, map->p) + 1;
3369 nentries = 0;
3370 for (i = 0; i < MAGIC_SETS; i++) {
3371 if (needsbyteswap)
3372 map->nmagic[i] = swap4(ptr[i + 2]);
3373 else
3374 map->nmagic[i] = ptr[i + 2];
3375 if (i != MAGIC_SETS - 1)
3376 map->magic[i + 1] = map->magic[i] + map->nmagic[i];
3377 nentries += map->nmagic[i];
3378 }
3379 if (entries != nentries + 1) {
3380 file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
3381 dbname, entries, nentries + 1);
3382 return -1;
3383 }
3384 if (needsbyteswap)
3385 for (i = 0; i < MAGIC_SETS; i++)
3386 byteswap(map->magic[i], map->nmagic[i]);
3387 return 0;
3388 }
3389
3390 /*
3391 * handle an mmaped file.
3392 */
3393 private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)3394 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
3395 {
3396 static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
3397 static const size_t m = sizeof(**map->magic);
3398 int fd = -1;
3399 size_t len;
3400 char *dbname;
3401 int rv = -1;
3402 uint32_t i;
3403 union {
3404 struct magic m;
3405 uint32_t h[2 + MAGIC_SETS];
3406 } hdr;
3407
3408 dbname = mkdbname(ms, fn, 1);
3409
3410 if (dbname == NULL)
3411 goto out;
3412
3413 if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
3414 {
3415 file_error(ms, errno, "cannot open `%s'", dbname);
3416 goto out;
3417 }
3418 memset(&hdr, 0, sizeof(hdr));
3419 hdr.h[0] = MAGICNO;
3420 hdr.h[1] = VERSIONNO;
3421 memcpy(hdr.h + 2, map->nmagic, nm);
3422
3423 if (write(fd, &hdr, sizeof(hdr)) != CAST(ssize_t, sizeof(hdr))) {
3424 file_error(ms, errno, "error writing `%s'", dbname);
3425 goto out2;
3426 }
3427
3428 for (i = 0; i < MAGIC_SETS; i++) {
3429 len = m * map->nmagic[i];
3430 if (write(fd, map->magic[i], len) != CAST(ssize_t, len)) {
3431 file_error(ms, errno, "error writing `%s'", dbname);
3432 goto out2;
3433 }
3434 }
3435
3436 rv = 0;
3437 out2:
3438 if (fd != -1)
3439 (void)close(fd);
3440 out:
3441 apprentice_unmap(map);
3442 free(dbname);
3443 return rv;
3444 }
3445
3446 private const char ext[] = ".mgc";
3447 /*
3448 * make a dbname
3449 */
3450 private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3451 mkdbname(struct magic_set *ms, const char *fn, int strip)
3452 {
3453 const char *p, *q;
3454 char *buf;
3455
3456 if (strip) {
3457 if ((p = strrchr(fn, '/')) != NULL)
3458 fn = ++p;
3459 }
3460
3461 for (q = fn; *q; q++)
3462 continue;
3463 /* Look for .mgc */
3464 for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3465 if (*p != *q)
3466 break;
3467
3468 /* Did not find .mgc, restore q */
3469 if (p >= ext)
3470 while (*q)
3471 q++;
3472
3473 q++;
3474 /* Compatibility with old code that looked in .mime */
3475 if (ms->flags & MAGIC_MIME) {
3476 if (asprintf(&buf, "%.*s.mime%s", CAST(int, q - fn), fn, ext)
3477 < 0)
3478 return NULL;
3479 if (access(buf, R_OK) != -1) {
3480 ms->flags &= MAGIC_MIME_TYPE;
3481 return buf;
3482 }
3483 free(buf);
3484 }
3485 if (asprintf(&buf, "%.*s%s", CAST(int, q - fn), fn, ext) < 0)
3486 return NULL;
3487
3488 /* Compatibility with old code that looked in .mime */
3489 if (strstr(fn, ".mime") != NULL)
3490 ms->flags &= MAGIC_MIME_TYPE;
3491 return buf;
3492 }
3493
3494 /*
3495 * Byteswap an mmap'ed file if needed
3496 */
3497 private void
byteswap(struct magic * magic,uint32_t nmagic)3498 byteswap(struct magic *magic, uint32_t nmagic)
3499 {
3500 uint32_t i;
3501 for (i = 0; i < nmagic; i++)
3502 bs1(&magic[i]);
3503 }
3504
3505 #if !defined(HAVE_BYTESWAP_H) && !defined(HAVE_SYS_BSWAP_H)
3506 /*
3507 * swap a short
3508 */
3509 private uint16_t
swap2(uint16_t sv)3510 swap2(uint16_t sv)
3511 {
3512 uint16_t rv;
3513 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3514 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3515 d[0] = s[1];
3516 d[1] = s[0];
3517 return rv;
3518 }
3519
3520 /*
3521 * swap an int
3522 */
3523 private uint32_t
swap4(uint32_t sv)3524 swap4(uint32_t sv)
3525 {
3526 uint32_t rv;
3527 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3528 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3529 d[0] = s[3];
3530 d[1] = s[2];
3531 d[2] = s[1];
3532 d[3] = s[0];
3533 return rv;
3534 }
3535
3536 /*
3537 * swap a quad
3538 */
3539 private uint64_t
swap8(uint64_t sv)3540 swap8(uint64_t sv)
3541 {
3542 uint64_t rv;
3543 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3544 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3545 # if 0
3546 d[0] = s[3];
3547 d[1] = s[2];
3548 d[2] = s[1];
3549 d[3] = s[0];
3550 d[4] = s[7];
3551 d[5] = s[6];
3552 d[6] = s[5];
3553 d[7] = s[4];
3554 # else
3555 d[0] = s[7];
3556 d[1] = s[6];
3557 d[2] = s[5];
3558 d[3] = s[4];
3559 d[4] = s[3];
3560 d[5] = s[2];
3561 d[6] = s[1];
3562 d[7] = s[0];
3563 # endif
3564 return rv;
3565 }
3566 #endif
3567
3568 protected uintmax_t
file_varint2uintmax_t(const unsigned char * us,int t,size_t * l)3569 file_varint2uintmax_t(const unsigned char *us, int t, size_t *l)
3570 {
3571 uintmax_t x = 0;
3572 const unsigned char *c;
3573 if (t == FILE_LEVARINT) {
3574 for (c = us; *c; c++) {
3575 if ((*c & 0x80) == 0)
3576 break;
3577 }
3578 if (l)
3579 *l = c - us + 1;
3580 for (; c >= us; c--) {
3581 x |= *c & 0x7f;
3582 x <<= 7;
3583 }
3584 } else {
3585 for (c = us; *c; c++) {
3586 x |= *c & 0x7f;
3587 if ((*c & 0x80) == 0)
3588 break;
3589 x <<= 7;
3590 }
3591 if (l)
3592 *l = c - us + 1;
3593 }
3594 return x;
3595 }
3596
3597
3598 /*
3599 * byteswap a single magic entry
3600 */
3601 private void
bs1(struct magic * m)3602 bs1(struct magic *m)
3603 {
3604 m->cont_level = swap2(m->cont_level);
3605 m->offset = swap4(CAST(uint32_t, m->offset));
3606 m->in_offset = swap4(CAST(uint32_t, m->in_offset));
3607 m->lineno = swap4(CAST(uint32_t, m->lineno));
3608 if (IS_STRING(m->type)) {
3609 m->str_range = swap4(m->str_range);
3610 m->str_flags = swap4(m->str_flags);
3611 }
3612 else {
3613 m->value.q = swap8(m->value.q);
3614 m->num_mask = swap8(m->num_mask);
3615 }
3616 }
3617
3618 protected size_t
file_pstring_length_size(struct magic_set * ms,const struct magic * m)3619 file_pstring_length_size(struct magic_set *ms, const struct magic *m)
3620 {
3621 switch (m->str_flags & PSTRING_LEN) {
3622 case PSTRING_1_LE:
3623 return 1;
3624 case PSTRING_2_LE:
3625 case PSTRING_2_BE:
3626 return 2;
3627 case PSTRING_4_LE:
3628 case PSTRING_4_BE:
3629 return 4;
3630 default:
3631 file_error(ms, 0, "corrupt magic file "
3632 "(bad pascal string length %d)",
3633 m->str_flags & PSTRING_LEN);
3634 return FILE_BADSIZE;
3635 }
3636 }
3637 protected size_t
file_pstring_get_length(struct magic_set * ms,const struct magic * m,const char * ss)3638 file_pstring_get_length(struct magic_set *ms, const struct magic *m,
3639 const char *ss)
3640 {
3641 size_t len = 0;
3642 const unsigned char *s = RCAST(const unsigned char *, ss);
3643 unsigned int s3, s2, s1, s0;
3644
3645 switch (m->str_flags & PSTRING_LEN) {
3646 case PSTRING_1_LE:
3647 len = *s;
3648 break;
3649 case PSTRING_2_LE:
3650 s0 = s[0];
3651 s1 = s[1];
3652 len = (s1 << 8) | s0;
3653 break;
3654 case PSTRING_2_BE:
3655 s0 = s[0];
3656 s1 = s[1];
3657 len = (s0 << 8) | s1;
3658 break;
3659 case PSTRING_4_LE:
3660 s0 = s[0];
3661 s1 = s[1];
3662 s2 = s[2];
3663 s3 = s[3];
3664 len = (s3 << 24) | (s2 << 16) | (s1 << 8) | s0;
3665 break;
3666 case PSTRING_4_BE:
3667 s0 = s[0];
3668 s1 = s[1];
3669 s2 = s[2];
3670 s3 = s[3];
3671 len = (s0 << 24) | (s1 << 16) | (s2 << 8) | s3;
3672 break;
3673 default:
3674 file_error(ms, 0, "corrupt magic file "
3675 "(bad pascal string length %d)",
3676 m->str_flags & PSTRING_LEN);
3677 return FILE_BADSIZE;
3678 }
3679
3680 if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF) {
3681 size_t l = file_pstring_length_size(ms, m);
3682 if (l == FILE_BADSIZE)
3683 return l;
3684 len -= l;
3685 }
3686
3687 return len;
3688 }
3689
3690 protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3691 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3692 {
3693 uint32_t i, j;
3694 struct mlist *mlist, *ml;
3695
3696 mlist = ms->mlist[1];
3697
3698 for (ml = mlist->next; ml != mlist; ml = ml->next) {
3699 struct magic *ma = ml->magic;
3700 for (i = 0; i < ml->nmagic; i++) {
3701 if (ma[i].type != FILE_NAME)
3702 continue;
3703 if (strcmp(ma[i].value.s, name) == 0) {
3704 v->magic = &ma[i];
3705 v->magic_rxcomp = &(ml->magic_rxcomp[i]);
3706 for (j = i + 1; j < ml->nmagic; j++)
3707 if (ma[j].cont_level == 0)
3708 break;
3709 v->nmagic = j - i;
3710 return 0;
3711 }
3712 }
3713 }
3714 return -1;
3715 }
3716