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 1.301 2021/02/23 00:51:11 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
54
55 #define EATAB {while (isascii(CAST(unsigned char, *l)) && \
56 isspace(CAST(unsigned char, *l))) ++l;}
57 #define LOWCASE(l) (isupper(CAST(unsigned char, l)) ? \
58 tolower(CAST(unsigned char, l)) : (l))
59 /*
60 * Work around a bug in headers on Digital Unix.
61 * At least confirmed for: OSF1 V4.0 878
62 */
63 #if defined(__osf__) && defined(__DECC)
64 #ifdef MAP_FAILED
65 #undef MAP_FAILED
66 #endif
67 #endif
68
69 #ifndef MAP_FAILED
70 #define MAP_FAILED (void *) -1
71 #endif
72
73 #ifndef MAP_FILE
74 #define MAP_FILE 0
75 #endif
76
77 #define ALLOC_CHUNK CAST(size_t, 10)
78 #define ALLOC_INCR CAST(size_t, 200)
79
80 #define MAP_TYPE_USER 0
81 #define MAP_TYPE_MALLOC 1
82 #define MAP_TYPE_MMAP 2
83
84 struct magic_entry {
85 struct magic *mp;
86 uint32_t cont_count;
87 uint32_t max_count;
88 };
89
90 struct magic_entry_set {
91 struct magic_entry *me;
92 uint32_t count;
93 uint32_t max;
94 };
95
96 struct magic_map {
97 void *p;
98 size_t len;
99 int type;
100 struct magic *magic[MAGIC_SETS];
101 uint32_t nmagic[MAGIC_SETS];
102 };
103
104 int file_formats[FILE_NAMES_SIZE];
105 const size_t file_nformats = FILE_NAMES_SIZE;
106 const char *file_names[FILE_NAMES_SIZE];
107 const size_t file_nnames = FILE_NAMES_SIZE;
108
109 private int getvalue(struct magic_set *ms, struct magic *, const char **, int);
110 private int hextoint(int);
111 private const char *getstr(struct magic_set *, struct magic *, const char *,
112 int);
113 private int parse(struct magic_set *, struct magic_entry *, const char *,
114 size_t, int);
115 private void eatsize(const char **);
116 private int apprentice_1(struct magic_set *, const char *, int);
117 private size_t apprentice_magic_strength(const struct magic *);
118 private int apprentice_sort(const void *, const void *);
119 private void apprentice_list(struct mlist *, int );
120 private struct magic_map *apprentice_load(struct magic_set *,
121 const char *, int);
122 private struct mlist *mlist_alloc(void);
123 private void mlist_free_all(struct magic_set *);
124 private void mlist_free(struct mlist *);
125 private void byteswap(struct magic *, uint32_t);
126 private void bs1(struct magic *);
127 private uint16_t swap2(uint16_t);
128 private uint32_t swap4(uint32_t);
129 private uint64_t swap8(uint64_t);
130 private char *mkdbname(struct magic_set *, const char *, int);
131 private struct magic_map *apprentice_buf(struct magic_set *, struct magic *,
132 size_t);
133 private struct magic_map *apprentice_map(struct magic_set *, const char *);
134 private int check_buffer(struct magic_set *, struct magic_map *, const char *);
135 private void apprentice_unmap(struct magic_map *);
136 private int apprentice_compile(struct magic_set *, struct magic_map *,
137 const char *);
138 private int check_format_type(const char *, int, const char **);
139 private int check_format(struct magic_set *, struct magic *);
140 private int get_op(char);
141 private int parse_mime(struct magic_set *, struct magic_entry *, const char *,
142 size_t);
143 private int parse_strength(struct magic_set *, struct magic_entry *,
144 const char *, size_t);
145 private int parse_apple(struct magic_set *, struct magic_entry *, const char *,
146 size_t);
147 private int parse_ext(struct magic_set *, struct magic_entry *, const char *,
148 size_t);
149
150
151 private size_t magicsize = sizeof(struct magic);
152
153 private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
154
155 private struct {
156 const char *name;
157 size_t len;
158 int (*fun)(struct magic_set *, struct magic_entry *, const char *,
159 size_t);
160 } bang[] = {
161 #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
162 DECLARE_FIELD(mime),
163 DECLARE_FIELD(apple),
164 DECLARE_FIELD(ext),
165 DECLARE_FIELD(strength),
166 #undef DECLARE_FIELD
167 { NULL, 0, NULL }
168 };
169
170 #ifdef COMPILE_ONLY
171
172 int main(int, char *[]);
173
174 int
main(int argc,char * argv[])175 main(int argc, char *argv[])
176 {
177 int ret;
178 struct magic_set *ms;
179 char *progname;
180
181 if ((progname = strrchr(argv[0], '/')) != NULL)
182 progname++;
183 else
184 progname = argv[0];
185
186 if (argc != 2) {
187 (void)fprintf(stderr, "Usage: %s file\n", progname);
188 return 1;
189 }
190
191 if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
192 (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
193 return 1;
194 }
195 ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
196 if (ret == 1)
197 (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
198 magic_close(ms);
199 return ret;
200 }
201 #endif /* COMPILE_ONLY */
202
203 struct type_tbl_s {
204 const char name[16];
205 const size_t len;
206 const int type;
207 const int format;
208 };
209
210 /*
211 * XXX - the actual Single UNIX Specification says that "long" means "long",
212 * as in the C data type, but we treat it as meaning "4-byte integer".
213 * Given that the OS X version of file 5.04 did the same, I guess that passes
214 * the actual test; having "long" be dependent on how big a "long" is on
215 * the machine running "file" is silly.
216 */
217 static const struct type_tbl_s type_tbl[] = {
218 # define XX(s) s, (sizeof(s) - 1)
219 # define XX_NULL "", 0
220 { XX("invalid"), FILE_INVALID, FILE_FMT_NONE },
221 { XX("byte"), FILE_BYTE, FILE_FMT_NUM },
222 { XX("short"), FILE_SHORT, FILE_FMT_NUM },
223 { XX("default"), FILE_DEFAULT, FILE_FMT_NONE },
224 { XX("long"), FILE_LONG, FILE_FMT_NUM },
225 { XX("string"), FILE_STRING, FILE_FMT_STR },
226 { XX("date"), FILE_DATE, FILE_FMT_STR },
227 { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM },
228 { XX("belong"), FILE_BELONG, FILE_FMT_NUM },
229 { XX("bedate"), FILE_BEDATE, FILE_FMT_STR },
230 { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM },
231 { XX("lelong"), FILE_LELONG, FILE_FMT_NUM },
232 { XX("ledate"), FILE_LEDATE, FILE_FMT_STR },
233 { XX("pstring"), FILE_PSTRING, FILE_FMT_STR },
234 { XX("ldate"), FILE_LDATE, FILE_FMT_STR },
235 { XX("beldate"), FILE_BELDATE, FILE_FMT_STR },
236 { XX("leldate"), FILE_LELDATE, FILE_FMT_STR },
237 { XX("regex"), FILE_REGEX, FILE_FMT_STR },
238 { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR },
239 { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR },
240 { XX("search"), FILE_SEARCH, FILE_FMT_STR },
241 { XX("medate"), FILE_MEDATE, FILE_FMT_STR },
242 { XX("meldate"), FILE_MELDATE, FILE_FMT_STR },
243 { XX("melong"), FILE_MELONG, FILE_FMT_NUM },
244 { XX("quad"), FILE_QUAD, FILE_FMT_QUAD },
245 { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD },
246 { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD },
247 { XX("qdate"), FILE_QDATE, FILE_FMT_STR },
248 { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR },
249 { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR },
250 { XX("qldate"), FILE_QLDATE, FILE_FMT_STR },
251 { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR },
252 { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR },
253 { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT },
254 { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT },
255 { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT },
256 { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE },
257 { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE },
258 { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE },
259 { XX("leid3"), FILE_LEID3, FILE_FMT_NUM },
260 { XX("beid3"), FILE_BEID3, FILE_FMT_NUM },
261 { XX("indirect"), FILE_INDIRECT, FILE_FMT_NUM },
262 { XX("qwdate"), FILE_QWDATE, FILE_FMT_STR },
263 { XX("leqwdate"), FILE_LEQWDATE, FILE_FMT_STR },
264 { XX("beqwdate"), FILE_BEQWDATE, FILE_FMT_STR },
265 { XX("name"), FILE_NAME, FILE_FMT_NONE },
266 { XX("use"), FILE_USE, FILE_FMT_NONE },
267 { XX("clear"), FILE_CLEAR, FILE_FMT_NONE },
268 { XX("der"), FILE_DER, FILE_FMT_STR },
269 { XX("guid"), FILE_GUID, FILE_FMT_STR },
270 { XX("offset"), FILE_OFFSET, FILE_FMT_QUAD },
271 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
272 };
273
274 /*
275 * These are not types, and cannot be preceded by "u" to make them
276 * unsigned.
277 */
278 static const struct type_tbl_s special_tbl[] = {
279 { XX("der"), FILE_DER, FILE_FMT_STR },
280 { XX("name"), FILE_NAME, FILE_FMT_STR },
281 { XX("use"), FILE_USE, FILE_FMT_STR },
282 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
283 };
284 # undef XX
285 # undef XX_NULL
286
287 private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)288 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
289 {
290 const struct type_tbl_s *p;
291
292 for (p = tbl; p->len; p++) {
293 if (strncmp(l, p->name, p->len) == 0) {
294 if (t)
295 *t = l + p->len;
296 break;
297 }
298 }
299 return p->type;
300 }
301
302 private off_t
maxoff_t(void)303 maxoff_t(void) {
304 if (/*CONSTCOND*/sizeof(off_t) == sizeof(int))
305 return CAST(off_t, INT_MAX);
306 if (/*CONSTCOND*/sizeof(off_t) == sizeof(long))
307 return CAST(off_t, LONG_MAX);
308 return 0x7fffffff;
309 }
310
311 private int
get_standard_integer_type(const char * l,const char ** t)312 get_standard_integer_type(const char *l, const char **t)
313 {
314 int type;
315
316 if (isalpha(CAST(unsigned char, l[1]))) {
317 switch (l[1]) {
318 case 'C':
319 /* "dC" and "uC" */
320 type = FILE_BYTE;
321 break;
322 case 'S':
323 /* "dS" and "uS" */
324 type = FILE_SHORT;
325 break;
326 case 'I':
327 case 'L':
328 /*
329 * "dI", "dL", "uI", and "uL".
330 *
331 * XXX - the actual Single UNIX Specification says
332 * that "L" means "long", as in the C data type,
333 * but we treat it as meaning "4-byte integer".
334 * Given that the OS X version of file 5.04 did
335 * the same, I guess that passes the actual SUS
336 * validation suite; having "dL" be dependent on
337 * how big a "long" is on the machine running
338 * "file" is silly.
339 */
340 type = FILE_LONG;
341 break;
342 case 'Q':
343 /* "dQ" and "uQ" */
344 type = FILE_QUAD;
345 break;
346 default:
347 /* "d{anything else}", "u{anything else}" */
348 return FILE_INVALID;
349 }
350 l += 2;
351 } else if (isdigit(CAST(unsigned char, l[1]))) {
352 /*
353 * "d{num}" and "u{num}"; we only support {num} values
354 * of 1, 2, 4, and 8 - the Single UNIX Specification
355 * doesn't say anything about whether arbitrary
356 * values should be supported, but both the Solaris 10
357 * and OS X Mountain Lion versions of file passed the
358 * Single UNIX Specification validation suite, and
359 * neither of them support values bigger than 8 or
360 * non-power-of-2 values.
361 */
362 if (isdigit(CAST(unsigned char, l[2]))) {
363 /* Multi-digit, so > 9 */
364 return FILE_INVALID;
365 }
366 switch (l[1]) {
367 case '1':
368 type = FILE_BYTE;
369 break;
370 case '2':
371 type = FILE_SHORT;
372 break;
373 case '4':
374 type = FILE_LONG;
375 break;
376 case '8':
377 type = FILE_QUAD;
378 break;
379 default:
380 /* XXX - what about 3, 5, 6, or 7? */
381 return FILE_INVALID;
382 }
383 l += 2;
384 } else {
385 /*
386 * "d" or "u" by itself.
387 */
388 type = FILE_LONG;
389 ++l;
390 }
391 if (t)
392 *t = l;
393 return type;
394 }
395
396 private void
init_file_tables(void)397 init_file_tables(void)
398 {
399 static int done = 0;
400 const struct type_tbl_s *p;
401
402 if (done)
403 return;
404 done++;
405
406 for (p = type_tbl; p->len; p++) {
407 assert(p->type < FILE_NAMES_SIZE);
408 file_names[p->type] = p->name;
409 file_formats[p->type] = p->format;
410 }
411 assert(p - type_tbl == FILE_NAMES_SIZE);
412 }
413
414 private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)415 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
416 {
417 struct mlist *ml;
418
419 mlp->map = NULL;
420 if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
421 return -1;
422
423 ml->map = idx == 0 ? map : NULL;
424 ml->magic = map->magic[idx];
425 ml->nmagic = map->nmagic[idx];
426
427 mlp->prev->next = ml;
428 ml->prev = mlp->prev;
429 ml->next = mlp;
430 mlp->prev = ml;
431 return 0;
432 }
433
434 /*
435 * Handle one file or directory.
436 */
437 private int
apprentice_1(struct magic_set * ms,const char * fn,int action)438 apprentice_1(struct magic_set *ms, const char *fn, int action)
439 {
440 struct magic_map *map;
441 #ifndef COMPILE_ONLY
442 struct mlist *ml;
443 size_t i;
444 #endif
445
446 if (magicsize != FILE_MAGICSIZE) {
447 file_error(ms, 0, "magic element size %lu != %lu",
448 CAST(unsigned long, sizeof(*map->magic[0])),
449 CAST(unsigned long, FILE_MAGICSIZE));
450 return -1;
451 }
452
453 if (action == FILE_COMPILE) {
454 map = apprentice_load(ms, fn, action);
455 if (map == NULL)
456 return -1;
457 return apprentice_compile(ms, map, fn);
458 }
459
460 #ifndef COMPILE_ONLY
461 map = apprentice_map(ms, fn);
462 if (map == NULL) {
463 if (ms->flags & MAGIC_CHECK)
464 file_magwarn(ms, "using regular magic file `%s'", fn);
465 map = apprentice_load(ms, fn, action);
466 if (map == NULL)
467 return -1;
468 }
469
470 for (i = 0; i < MAGIC_SETS; i++) {
471 if (add_mlist(ms->mlist[i], map, i) == -1) {
472 /* failed to add to any list, free explicitly */
473 if (i == 0)
474 apprentice_unmap(map);
475 else
476 mlist_free_all(ms);
477 file_oomem(ms, sizeof(*ml));
478 return -1;
479 }
480 }
481
482 if (action == FILE_LIST) {
483 for (i = 0; i < MAGIC_SETS; i++) {
484 printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
485 i);
486 apprentice_list(ms->mlist[i], BINTEST);
487 printf("Text patterns:\n");
488 apprentice_list(ms->mlist[i], TEXTTEST);
489 }
490 }
491 return 0;
492 #else
493 return 0;
494 #endif /* COMPILE_ONLY */
495 }
496
497 protected void
file_ms_free(struct magic_set * ms)498 file_ms_free(struct magic_set *ms)
499 {
500 size_t i;
501 if (ms == NULL)
502 return;
503 for (i = 0; i < MAGIC_SETS; i++)
504 mlist_free(ms->mlist[i]);
505 free(ms->o.pbuf);
506 free(ms->o.buf);
507 free(ms->c.li);
508 free(ms);
509 }
510
511 protected struct magic_set *
file_ms_alloc(int flags)512 file_ms_alloc(int flags)
513 {
514 struct magic_set *ms;
515 size_t i, len;
516
517 if ((ms = CAST(struct magic_set *, calloc(CAST(size_t, 1u),
518 sizeof(struct magic_set)))) == NULL)
519 return NULL;
520
521 if (magic_setflags(ms, flags) == -1) {
522 errno = EINVAL;
523 goto free;
524 }
525
526 ms->o.buf = ms->o.pbuf = NULL;
527 ms->o.blen = 0;
528 len = (ms->c.len = 10) * sizeof(*ms->c.li);
529
530 if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
531 goto free;
532
533 ms->event_flags = 0;
534 ms->error = -1;
535 for (i = 0; i < MAGIC_SETS; i++)
536 ms->mlist[i] = NULL;
537 ms->file = "unknown";
538 ms->line = 0;
539 ms->indir_max = FILE_INDIR_MAX;
540 ms->name_max = FILE_NAME_MAX;
541 ms->elf_shnum_max = FILE_ELF_SHNUM_MAX;
542 ms->elf_phnum_max = FILE_ELF_PHNUM_MAX;
543 ms->elf_notes_max = FILE_ELF_NOTES_MAX;
544 ms->regex_max = FILE_REGEX_MAX;
545 ms->bytes_max = FILE_BYTES_MAX;
546 ms->encoding_max = FILE_ENCODING_MAX;
547 return ms;
548 free:
549 free(ms);
550 return NULL;
551 }
552
553 private void
apprentice_unmap(struct magic_map * map)554 apprentice_unmap(struct magic_map *map)
555 {
556 size_t i;
557 if (map == NULL)
558 return;
559
560 switch (map->type) {
561 case MAP_TYPE_USER:
562 break;
563 case MAP_TYPE_MALLOC:
564 for (i = 0; i < MAGIC_SETS; i++) {
565 void *b = map->magic[i];
566 void *p = map->p;
567 if (CAST(char *, b) >= CAST(char *, p) &&
568 CAST(char *, b) <= CAST(char *, p) + map->len)
569 continue;
570 free(map->magic[i]);
571 }
572 free(map->p);
573 break;
574 #ifdef QUICK
575 case MAP_TYPE_MMAP:
576 if (map->p && map->p != MAP_FAILED)
577 (void)munmap(map->p, map->len);
578 break;
579 #endif
580 default:
581 abort();
582 }
583 free(map);
584 }
585
586 private struct mlist *
mlist_alloc(void)587 mlist_alloc(void)
588 {
589 struct mlist *mlist;
590 if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
591 return NULL;
592 }
593 mlist->next = mlist->prev = mlist;
594 return mlist;
595 }
596
597 private void
mlist_free_all(struct magic_set * ms)598 mlist_free_all(struct magic_set *ms)
599 {
600 size_t i;
601
602 for (i = 0; i < MAGIC_SETS; i++) {
603 mlist_free(ms->mlist[i]);
604 ms->mlist[i] = NULL;
605 }
606 }
607
608 private void
mlist_free_one(struct mlist * ml)609 mlist_free_one(struct mlist *ml)
610 {
611 if (ml->map)
612 apprentice_unmap(CAST(struct magic_map *, ml->map));
613 free(ml);
614 }
615
616 private void
mlist_free(struct mlist * mlist)617 mlist_free(struct mlist *mlist)
618 {
619 struct mlist *ml, *next;
620
621 if (mlist == NULL)
622 return;
623
624 for (ml = mlist->next; ml != mlist;) {
625 next = ml->next;
626 mlist_free_one(ml);
627 ml = next;
628 }
629 mlist_free_one(mlist);
630 }
631
632 #ifndef COMPILE_ONLY
633 /* void **bufs: an array of compiled magic files */
634 protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)635 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
636 size_t *sizes, size_t nbufs)
637 {
638 size_t i, j;
639 struct mlist *ml;
640 struct magic_map *map;
641
642 if (nbufs == 0)
643 return -1;
644
645 (void)file_reset(ms, 0);
646
647 init_file_tables();
648
649 for (i = 0; i < MAGIC_SETS; i++) {
650 mlist_free(ms->mlist[i]);
651 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
652 file_oomem(ms, sizeof(*ms->mlist[i]));
653 goto fail;
654 }
655 }
656
657 for (i = 0; i < nbufs; i++) {
658 map = apprentice_buf(ms, bufs[i], sizes[i]);
659 if (map == NULL)
660 goto fail;
661
662 for (j = 0; j < MAGIC_SETS; j++) {
663 if (add_mlist(ms->mlist[j], map, j) == -1) {
664 file_oomem(ms, sizeof(*ml));
665 goto fail;
666 }
667 }
668 }
669
670 return 0;
671 fail:
672 mlist_free_all(ms);
673 return -1;
674 }
675 #endif
676
677 /* const char *fn: list of magic files and directories */
678 protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)679 file_apprentice(struct magic_set *ms, const char *fn, int action)
680 {
681 char *p, *mfn;
682 int fileerr, errs = -1;
683 size_t i, j;
684
685 (void)file_reset(ms, 0);
686
687 if ((fn = magic_getpath(fn, action)) == NULL)
688 return -1;
689
690 init_file_tables();
691
692 if ((mfn = strdup(fn)) == NULL) {
693 file_oomem(ms, strlen(fn));
694 return -1;
695 }
696
697 for (i = 0; i < MAGIC_SETS; i++) {
698 mlist_free(ms->mlist[i]);
699 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
700 file_oomem(ms, sizeof(*ms->mlist[i]));
701 for (j = 0; j < i; j++) {
702 mlist_free(ms->mlist[j]);
703 ms->mlist[j] = NULL;
704 }
705 free(mfn);
706 return -1;
707 }
708 }
709 fn = mfn;
710
711 while (fn) {
712 p = strchr(fn, PATHSEP);
713 if (p)
714 *p++ = '\0';
715 if (*fn == '\0')
716 break;
717 fileerr = apprentice_1(ms, fn, action);
718 errs = MAX(errs, fileerr);
719 fn = p;
720 }
721
722 free(mfn);
723
724 if (errs == -1) {
725 for (i = 0; i < MAGIC_SETS; i++) {
726 mlist_free(ms->mlist[i]);
727 ms->mlist[i] = NULL;
728 }
729 file_error(ms, 0, "could not find any valid magic files!");
730 return -1;
731 }
732
733 #if 0
734 /*
735 * Always leave the database loaded
736 */
737 if (action == FILE_LOAD)
738 return 0;
739
740 for (i = 0; i < MAGIC_SETS; i++) {
741 mlist_free(ms->mlist[i]);
742 ms->mlist[i] = NULL;
743 }
744 #endif
745
746 switch (action) {
747 case FILE_LOAD:
748 case FILE_COMPILE:
749 case FILE_CHECK:
750 case FILE_LIST:
751 return 0;
752 default:
753 file_error(ms, 0, "Invalid action %d", action);
754 return -1;
755 }
756 }
757
758 /*
759 * Compute the real length of a magic expression, for the purposes
760 * of determining how "strong" a magic expression is (approximating
761 * how specific its matches are):
762 * - magic characters count 0 unless escaped.
763 * - [] expressions count 1
764 * - {} expressions count 0
765 * - regular characters or escaped magic characters count 1
766 * - 0 length expressions count as one
767 */
768 private size_t
nonmagic(const char * str)769 nonmagic(const char *str)
770 {
771 const char *p;
772 size_t rv = 0;
773
774 for (p = str; *p; p++)
775 switch (*p) {
776 case '\\': /* Escaped anything counts 1 */
777 if (!*++p)
778 p--;
779 rv++;
780 continue;
781 case '?': /* Magic characters count 0 */
782 case '*':
783 case '.':
784 case '+':
785 case '^':
786 case '$':
787 continue;
788 case '[': /* Bracketed expressions count 1 the ']' */
789 while (*p && *p != ']')
790 p++;
791 p--;
792 continue;
793 case '{': /* Braced expressions count 0 */
794 while (*p && *p != '}')
795 p++;
796 if (!*p)
797 p--;
798 continue;
799 default: /* Anything else counts 1 */
800 rv++;
801 continue;
802 }
803
804 return rv == 0 ? 1 : rv; /* Return at least 1 */
805 }
806
807
808 private size_t
typesize(int type)809 typesize(int type)
810 {
811 switch (type) {
812 case FILE_BYTE:
813 return 1;
814
815 case FILE_SHORT:
816 case FILE_LESHORT:
817 case FILE_BESHORT:
818 return 2;
819
820 case FILE_LONG:
821 case FILE_LELONG:
822 case FILE_BELONG:
823 case FILE_MELONG:
824 return 4;
825
826 case FILE_DATE:
827 case FILE_LEDATE:
828 case FILE_BEDATE:
829 case FILE_MEDATE:
830 case FILE_LDATE:
831 case FILE_LELDATE:
832 case FILE_BELDATE:
833 case FILE_MELDATE:
834 case FILE_FLOAT:
835 case FILE_BEFLOAT:
836 case FILE_LEFLOAT:
837 return 4;
838
839 case FILE_QUAD:
840 case FILE_BEQUAD:
841 case FILE_LEQUAD:
842 case FILE_QDATE:
843 case FILE_LEQDATE:
844 case FILE_BEQDATE:
845 case FILE_QLDATE:
846 case FILE_LEQLDATE:
847 case FILE_BEQLDATE:
848 case FILE_QWDATE:
849 case FILE_LEQWDATE:
850 case FILE_BEQWDATE:
851 case FILE_DOUBLE:
852 case FILE_BEDOUBLE:
853 case FILE_LEDOUBLE:
854 case FILE_OFFSET:
855 return 8;
856
857 case FILE_GUID:
858 return 16;
859
860 default:
861 return FILE_BADSIZE;
862 }
863 }
864
865 /*
866 * Get weight of this magic entry, for sorting purposes.
867 */
868 private size_t
apprentice_magic_strength(const struct magic * m)869 apprentice_magic_strength(const struct magic *m)
870 {
871 #define MULT 10U
872 size_t ts, v;
873 ssize_t val = 2 * MULT; /* baseline strength */
874
875 switch (m->type) {
876 case FILE_DEFAULT: /* make sure this sorts last */
877 if (m->factor_op != FILE_FACTOR_OP_NONE)
878 abort();
879 return 0;
880
881 case FILE_BYTE:
882 case FILE_SHORT:
883 case FILE_LESHORT:
884 case FILE_BESHORT:
885 case FILE_LONG:
886 case FILE_LELONG:
887 case FILE_BELONG:
888 case FILE_MELONG:
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_QUAD:
901 case FILE_BEQUAD:
902 case FILE_LEQUAD:
903 case FILE_QDATE:
904 case FILE_LEQDATE:
905 case FILE_BEQDATE:
906 case FILE_QLDATE:
907 case FILE_LEQLDATE:
908 case FILE_BEQLDATE:
909 case FILE_QWDATE:
910 case FILE_LEQWDATE:
911 case FILE_BEQWDATE:
912 case FILE_DOUBLE:
913 case FILE_BEDOUBLE:
914 case FILE_LEDOUBLE:
915 case FILE_GUID:
916 case FILE_OFFSET:
917 ts = typesize(m->type);
918 if (ts == FILE_BADSIZE)
919 abort();
920 val += ts * MULT;
921 break;
922
923 case FILE_PSTRING:
924 case FILE_STRING:
925 val += m->vallen * MULT;
926 break;
927
928 case FILE_BESTRING16:
929 case FILE_LESTRING16:
930 val += m->vallen * MULT / 2;
931 break;
932
933 case FILE_SEARCH:
934 if (m->vallen == 0)
935 break;
936 val += m->vallen * MAX(MULT / m->vallen, 1);
937 break;
938
939 case FILE_REGEX:
940 v = nonmagic(m->value.s);
941 val += v * MAX(MULT / v, 1);
942 break;
943
944 case FILE_INDIRECT:
945 case FILE_NAME:
946 case FILE_USE:
947 break;
948
949 case FILE_DER:
950 val += MULT;
951 break;
952
953 default:
954 (void)fprintf(stderr, "Bad type %d\n", m->type);
955 abort();
956 }
957
958 switch (m->reln) {
959 case 'x': /* matches anything penalize */
960 case '!': /* matches almost anything penalize */
961 val = 0;
962 break;
963
964 case '=': /* Exact match, prefer */
965 val += MULT;
966 break;
967
968 case '>':
969 case '<': /* comparison match reduce strength */
970 val -= 2 * MULT;
971 break;
972
973 case '^':
974 case '&': /* masking bits, we could count them too */
975 val -= MULT;
976 break;
977
978 default:
979 (void)fprintf(stderr, "Bad relation %c\n", m->reln);
980 abort();
981 }
982
983 switch (m->factor_op) {
984 case FILE_FACTOR_OP_NONE:
985 break;
986 case FILE_FACTOR_OP_PLUS:
987 val += m->factor;
988 break;
989 case FILE_FACTOR_OP_MINUS:
990 val -= m->factor;
991 break;
992 case FILE_FACTOR_OP_TIMES:
993 val *= m->factor;
994 break;
995 case FILE_FACTOR_OP_DIV:
996 val /= m->factor;
997 break;
998 default:
999 abort();
1000 }
1001
1002 if (val <= 0) /* ensure we only return 0 for FILE_DEFAULT */
1003 val = 1;
1004
1005 /*
1006 * Magic entries with no description get a bonus because they depend
1007 * on subsequent magic entries to print something.
1008 */
1009 if (m->desc[0] == '\0')
1010 val++;
1011 return val;
1012 }
1013
1014 /*
1015 * Sort callback for sorting entries by "strength" (basically length)
1016 */
1017 private int
apprentice_sort(const void * a,const void * b)1018 apprentice_sort(const void *a, const void *b)
1019 {
1020 const struct magic_entry *ma = CAST(const struct magic_entry *, a);
1021 const struct magic_entry *mb = CAST(const struct magic_entry *, b);
1022 size_t sa = apprentice_magic_strength(ma->mp);
1023 size_t sb = apprentice_magic_strength(mb->mp);
1024 if (sa == sb)
1025 return 0;
1026 else if (sa > sb)
1027 return -1;
1028 else
1029 return 1;
1030 }
1031
1032 /*
1033 * Shows sorted patterns list in the order which is used for the matching
1034 */
1035 private void
apprentice_list(struct mlist * mlist,int mode)1036 apprentice_list(struct mlist *mlist, int mode)
1037 {
1038 uint32_t magindex = 0;
1039 struct mlist *ml;
1040 for (ml = mlist->next; ml != mlist; ml = ml->next) {
1041 for (magindex = 0; magindex < ml->nmagic; magindex++) {
1042 struct magic *m = &ml->magic[magindex];
1043 if ((m->flag & mode) != mode) {
1044 /* Skip sub-tests */
1045 while (magindex + 1 < ml->nmagic &&
1046 ml->magic[magindex + 1].cont_level != 0)
1047 ++magindex;
1048 continue; /* Skip to next top-level test*/
1049 }
1050
1051 /*
1052 * Try to iterate over the tree until we find item with
1053 * description/mimetype.
1054 */
1055 while (magindex + 1 < ml->nmagic &&
1056 ml->magic[magindex + 1].cont_level != 0 &&
1057 *ml->magic[magindex].desc == '\0' &&
1058 *ml->magic[magindex].mimetype == '\0')
1059 magindex++;
1060
1061 printf("Strength = %3" SIZE_T_FORMAT "u@%u: %s [%s]\n",
1062 apprentice_magic_strength(m),
1063 ml->magic[magindex].lineno,
1064 ml->magic[magindex].desc,
1065 ml->magic[magindex].mimetype);
1066 }
1067 }
1068 }
1069
1070 private void
set_test_type(struct magic * mstart,struct magic * m)1071 set_test_type(struct magic *mstart, struct magic *m)
1072 {
1073 switch (m->type) {
1074 case FILE_BYTE:
1075 case FILE_SHORT:
1076 case FILE_LONG:
1077 case FILE_DATE:
1078 case FILE_BESHORT:
1079 case FILE_BELONG:
1080 case FILE_BEDATE:
1081 case FILE_LESHORT:
1082 case FILE_LELONG:
1083 case FILE_LEDATE:
1084 case FILE_LDATE:
1085 case FILE_BELDATE:
1086 case FILE_LELDATE:
1087 case FILE_MEDATE:
1088 case FILE_MELDATE:
1089 case FILE_MELONG:
1090 case FILE_QUAD:
1091 case FILE_LEQUAD:
1092 case FILE_BEQUAD:
1093 case FILE_QDATE:
1094 case FILE_LEQDATE:
1095 case FILE_BEQDATE:
1096 case FILE_QLDATE:
1097 case FILE_LEQLDATE:
1098 case FILE_BEQLDATE:
1099 case FILE_QWDATE:
1100 case FILE_LEQWDATE:
1101 case FILE_BEQWDATE:
1102 case FILE_FLOAT:
1103 case FILE_BEFLOAT:
1104 case FILE_LEFLOAT:
1105 case FILE_DOUBLE:
1106 case FILE_BEDOUBLE:
1107 case FILE_LEDOUBLE:
1108 case FILE_DER:
1109 case FILE_GUID:
1110 case FILE_OFFSET:
1111 mstart->flag |= BINTEST;
1112 break;
1113 case FILE_STRING:
1114 case FILE_PSTRING:
1115 case FILE_BESTRING16:
1116 case FILE_LESTRING16:
1117 /* Allow text overrides */
1118 if (mstart->str_flags & STRING_TEXTTEST)
1119 mstart->flag |= TEXTTEST;
1120 else
1121 mstart->flag |= BINTEST;
1122 break;
1123 case FILE_REGEX:
1124 case FILE_SEARCH:
1125 /* Check for override */
1126 if (mstart->str_flags & STRING_BINTEST)
1127 mstart->flag |= BINTEST;
1128 if (mstart->str_flags & STRING_TEXTTEST)
1129 mstart->flag |= TEXTTEST;
1130
1131 if (mstart->flag & (TEXTTEST|BINTEST))
1132 break;
1133
1134 /* binary test if pattern is not text */
1135 if (file_looks_utf8(m->value.us, CAST(size_t, m->vallen), NULL,
1136 NULL) <= 0)
1137 mstart->flag |= BINTEST;
1138 else
1139 mstart->flag |= TEXTTEST;
1140 break;
1141 case FILE_DEFAULT:
1142 /* can't deduce anything; we shouldn't see this at the
1143 top level anyway */
1144 break;
1145 case FILE_INVALID:
1146 default:
1147 /* invalid search type, but no need to complain here */
1148 break;
1149 }
1150 }
1151
1152 private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1153 addentry(struct magic_set *ms, struct magic_entry *me,
1154 struct magic_entry_set *mset)
1155 {
1156 size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1157 if (mset[i].count == mset[i].max) {
1158 struct magic_entry *mp;
1159
1160 mset[i].max += ALLOC_INCR;
1161 if ((mp = CAST(struct magic_entry *,
1162 realloc(mset[i].me, sizeof(*mp) * mset[i].max))) ==
1163 NULL) {
1164 file_oomem(ms, sizeof(*mp) * mset[i].max);
1165 return -1;
1166 }
1167 (void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1168 ALLOC_INCR);
1169 mset[i].me = mp;
1170 }
1171 mset[i].me[mset[i].count++] = *me;
1172 memset(me, 0, sizeof(*me));
1173 return 0;
1174 }
1175
1176 /*
1177 * Load and parse one file.
1178 */
1179 private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1180 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1181 struct magic_entry_set *mset)
1182 {
1183 size_t lineno = 0, llen = 0;
1184 char *line = NULL;
1185 ssize_t len;
1186 struct magic_entry me;
1187
1188 FILE *f = fopen(ms->file = fn, "r");
1189 if (f == NULL) {
1190 if (errno != ENOENT)
1191 file_error(ms, errno, "cannot read magic file `%s'",
1192 fn);
1193 (*errs)++;
1194 return;
1195 }
1196
1197 memset(&me, 0, sizeof(me));
1198 /* read and parse this file */
1199 for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1200 ms->line++) {
1201 if (len == 0) /* null line, garbage, etc */
1202 continue;
1203 if (line[len - 1] == '\n') {
1204 lineno++;
1205 line[len - 1] = '\0'; /* delete newline */
1206 }
1207 switch (line[0]) {
1208 case '\0': /* empty, do not parse */
1209 case '#': /* comment, do not parse */
1210 continue;
1211 case '!':
1212 if (line[1] == ':') {
1213 size_t i;
1214
1215 for (i = 0; bang[i].name != NULL; i++) {
1216 if (CAST(size_t, len - 2) > bang[i].len &&
1217 memcmp(bang[i].name, line + 2,
1218 bang[i].len) == 0)
1219 break;
1220 }
1221 if (bang[i].name == NULL) {
1222 file_error(ms, 0,
1223 "Unknown !: entry `%s'", line);
1224 (*errs)++;
1225 continue;
1226 }
1227 if (me.mp == NULL) {
1228 file_error(ms, 0,
1229 "No current entry for :!%s type",
1230 bang[i].name);
1231 (*errs)++;
1232 continue;
1233 }
1234 if ((*bang[i].fun)(ms, &me,
1235 line + bang[i].len + 2,
1236 len - bang[i].len - 2) != 0) {
1237 (*errs)++;
1238 continue;
1239 }
1240 continue;
1241 }
1242 /*FALLTHROUGH*/
1243 default:
1244 again:
1245 switch (parse(ms, &me, line, lineno, action)) {
1246 case 0:
1247 continue;
1248 case 1:
1249 (void)addentry(ms, &me, mset);
1250 goto again;
1251 default:
1252 (*errs)++;
1253 break;
1254 }
1255 }
1256 }
1257 if (me.mp)
1258 (void)addentry(ms, &me, mset);
1259 free(line);
1260 (void)fclose(f);
1261 }
1262
1263 /*
1264 * parse a file or directory of files
1265 * const char *fn: name of magic file or directory
1266 */
1267 private int
cmpstrp(const void * p1,const void * p2)1268 cmpstrp(const void *p1, const void *p2)
1269 {
1270 return strcmp(*RCAST(char *const *, p1), *RCAST(char *const *, p2));
1271 }
1272
1273
1274 private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1275 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1276 uint32_t starttest)
1277 {
1278 static const char text[] = "text";
1279 static const char binary[] = "binary";
1280 static const size_t len = sizeof(text);
1281
1282 uint32_t i = starttest;
1283
1284 do {
1285 set_test_type(me[starttest].mp, me[i].mp);
1286 if ((ms->flags & MAGIC_DEBUG) == 0)
1287 continue;
1288 (void)fprintf(stderr, "%s%s%s: %s\n",
1289 me[i].mp->mimetype,
1290 me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1291 me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1292 me[i].mp->flag & BINTEST ? binary : text);
1293 if (me[i].mp->flag & BINTEST) {
1294 char *p = strstr(me[i].mp->desc, text);
1295 if (p && (p == me[i].mp->desc ||
1296 isspace(CAST(unsigned char, p[-1]))) &&
1297 (p + len - me[i].mp->desc == MAXstring
1298 || (p[len] == '\0' ||
1299 isspace(CAST(unsigned char, p[len])))))
1300 (void)fprintf(stderr, "*** Possible "
1301 "binary test for text type\n");
1302 }
1303 } while (++i < nme && me[i].mp->cont_level != 0);
1304 return i;
1305 }
1306
1307 private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1308 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1309 {
1310 uint32_t i;
1311 for (i = 0; i < nme; i++) {
1312 if (me[i].mp->cont_level == 0 &&
1313 me[i].mp->type == FILE_DEFAULT) {
1314 while (++i < nme)
1315 if (me[i].mp->cont_level == 0)
1316 break;
1317 if (i != nme) {
1318 /* XXX - Ugh! */
1319 ms->line = me[i].mp->lineno;
1320 file_magwarn(ms,
1321 "level 0 \"default\" did not sort last");
1322 }
1323 return;
1324 }
1325 }
1326 }
1327
1328 private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1329 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1330 struct magic **ma, uint32_t *nma)
1331 {
1332 uint32_t i, mentrycount = 0;
1333 size_t slen;
1334
1335 for (i = 0; i < nme; i++)
1336 mentrycount += me[i].cont_count;
1337
1338 slen = sizeof(**ma) * mentrycount;
1339 if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1340 file_oomem(ms, slen);
1341 return -1;
1342 }
1343
1344 mentrycount = 0;
1345 for (i = 0; i < nme; i++) {
1346 (void)memcpy(*ma + mentrycount, me[i].mp,
1347 me[i].cont_count * sizeof(**ma));
1348 mentrycount += me[i].cont_count;
1349 }
1350 *nma = mentrycount;
1351 return 0;
1352 }
1353
1354 private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1355 magic_entry_free(struct magic_entry *me, uint32_t nme)
1356 {
1357 uint32_t i;
1358 if (me == NULL)
1359 return;
1360 for (i = 0; i < nme; i++)
1361 free(me[i].mp);
1362 free(me);
1363 }
1364
1365 private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1366 apprentice_load(struct magic_set *ms, const char *fn, int action)
1367 {
1368 int errs = 0;
1369 uint32_t i, j;
1370 size_t files = 0, maxfiles = 0;
1371 char **filearr = NULL, *mfn;
1372 struct stat st;
1373 struct magic_map *map;
1374 struct magic_entry_set mset[MAGIC_SETS];
1375 DIR *dir;
1376 struct dirent *d;
1377
1378 memset(mset, 0, sizeof(mset));
1379 ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */
1380
1381
1382 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1383 {
1384 file_oomem(ms, sizeof(*map));
1385 return NULL;
1386 }
1387 map->type = MAP_TYPE_MALLOC;
1388
1389 /* print silly verbose header for USG compat. */
1390 if (action == FILE_CHECK)
1391 (void)fprintf(stderr, "%s\n", usg_hdr);
1392
1393 /* load directory or file */
1394 if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1395 dir = opendir(fn);
1396 if (!dir) {
1397 errs++;
1398 goto out;
1399 }
1400 while ((d = readdir(dir)) != NULL) {
1401 if (d->d_name[0] == '.')
1402 continue;
1403 if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1404 file_oomem(ms,
1405 strlen(fn) + strlen(d->d_name) + 2);
1406 errs++;
1407 closedir(dir);
1408 goto out;
1409 }
1410 if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1411 free(mfn);
1412 continue;
1413 }
1414 if (files >= maxfiles) {
1415 size_t mlen;
1416 char **nfilearr;
1417 maxfiles = (maxfiles + 1) * 2;
1418 mlen = maxfiles * sizeof(*filearr);
1419 if ((nfilearr = CAST(char **,
1420 realloc(filearr, mlen))) == NULL) {
1421 file_oomem(ms, mlen);
1422 free(mfn);
1423 closedir(dir);
1424 errs++;
1425 goto out;
1426 }
1427 filearr = nfilearr;
1428 }
1429 filearr[files++] = mfn;
1430 }
1431 closedir(dir);
1432 if (filearr) {
1433 qsort(filearr, files, sizeof(*filearr), cmpstrp);
1434 for (i = 0; i < files; i++) {
1435 load_1(ms, action, filearr[i], &errs, mset);
1436 free(filearr[i]);
1437 }
1438 free(filearr);
1439 filearr = NULL;
1440 }
1441 } else
1442 load_1(ms, action, fn, &errs, mset);
1443 if (errs)
1444 goto out;
1445
1446 for (j = 0; j < MAGIC_SETS; j++) {
1447 /* Set types of tests */
1448 for (i = 0; i < mset[j].count; ) {
1449 if (mset[j].me[i].mp->cont_level != 0) {
1450 i++;
1451 continue;
1452 }
1453 i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1454 }
1455 if (mset[j].me)
1456 qsort(mset[j].me, mset[j].count, sizeof(*mset[j].me),
1457 apprentice_sort);
1458
1459 /*
1460 * Make sure that any level 0 "default" line is last
1461 * (if one exists).
1462 */
1463 set_last_default(ms, mset[j].me, mset[j].count);
1464
1465 /* coalesce per file arrays into a single one, if needed */
1466 if (mset[j].count == 0)
1467 continue;
1468
1469 if (coalesce_entries(ms, mset[j].me, mset[j].count,
1470 &map->magic[j], &map->nmagic[j]) == -1) {
1471 errs++;
1472 goto out;
1473 }
1474 }
1475
1476 out:
1477 free(filearr);
1478 for (j = 0; j < MAGIC_SETS; j++)
1479 magic_entry_free(mset[j].me, mset[j].count);
1480
1481 if (errs) {
1482 apprentice_unmap(map);
1483 return NULL;
1484 }
1485 return map;
1486 }
1487
1488 /*
1489 * extend the sign bit if the comparison is to be signed
1490 */
1491 protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1492 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1493 {
1494 if (!(m->flag & UNSIGNED)) {
1495 switch(m->type) {
1496 /*
1497 * Do not remove the casts below. They are
1498 * vital. When later compared with the data,
1499 * the sign extension must have happened.
1500 */
1501 case FILE_BYTE:
1502 v = CAST(signed char, v);
1503 break;
1504 case FILE_SHORT:
1505 case FILE_BESHORT:
1506 case FILE_LESHORT:
1507 v = CAST(short, v);
1508 break;
1509 case FILE_DATE:
1510 case FILE_BEDATE:
1511 case FILE_LEDATE:
1512 case FILE_MEDATE:
1513 case FILE_LDATE:
1514 case FILE_BELDATE:
1515 case FILE_LELDATE:
1516 case FILE_MELDATE:
1517 case FILE_LONG:
1518 case FILE_BELONG:
1519 case FILE_LELONG:
1520 case FILE_MELONG:
1521 case FILE_FLOAT:
1522 case FILE_BEFLOAT:
1523 case FILE_LEFLOAT:
1524 v = CAST(int32_t, v);
1525 break;
1526 case FILE_QUAD:
1527 case FILE_BEQUAD:
1528 case FILE_LEQUAD:
1529 case FILE_QDATE:
1530 case FILE_QLDATE:
1531 case FILE_QWDATE:
1532 case FILE_BEQDATE:
1533 case FILE_BEQLDATE:
1534 case FILE_BEQWDATE:
1535 case FILE_LEQDATE:
1536 case FILE_LEQLDATE:
1537 case FILE_LEQWDATE:
1538 case FILE_DOUBLE:
1539 case FILE_BEDOUBLE:
1540 case FILE_LEDOUBLE:
1541 case FILE_OFFSET:
1542 v = CAST(int64_t, v);
1543 break;
1544 case FILE_STRING:
1545 case FILE_PSTRING:
1546 case FILE_BESTRING16:
1547 case FILE_LESTRING16:
1548 case FILE_REGEX:
1549 case FILE_SEARCH:
1550 case FILE_DEFAULT:
1551 case FILE_INDIRECT:
1552 case FILE_NAME:
1553 case FILE_USE:
1554 case FILE_CLEAR:
1555 case FILE_DER:
1556 case FILE_GUID:
1557 break;
1558 default:
1559 if (ms->flags & MAGIC_CHECK)
1560 file_magwarn(ms, "cannot happen: m->type=%d\n",
1561 m->type);
1562 return FILE_BADSIZE;
1563 }
1564 }
1565 return v;
1566 }
1567
1568 private int
string_modifier_check(struct magic_set * ms,struct magic * m)1569 string_modifier_check(struct magic_set *ms, struct magic *m)
1570 {
1571 if ((ms->flags & MAGIC_CHECK) == 0)
1572 return 0;
1573
1574 if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1575 (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1576 file_magwarn(ms,
1577 "'/BHhLl' modifiers are only allowed for pascal strings\n");
1578 return -1;
1579 }
1580 switch (m->type) {
1581 case FILE_BESTRING16:
1582 case FILE_LESTRING16:
1583 if (m->str_flags != 0) {
1584 file_magwarn(ms,
1585 "no modifiers allowed for 16-bit strings\n");
1586 return -1;
1587 }
1588 break;
1589 case FILE_STRING:
1590 case FILE_PSTRING:
1591 if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1592 file_magwarn(ms,
1593 "'/%c' only allowed on regex and search\n",
1594 CHAR_REGEX_OFFSET_START);
1595 return -1;
1596 }
1597 break;
1598 case FILE_SEARCH:
1599 if (m->str_range == 0) {
1600 file_magwarn(ms,
1601 "missing range; defaulting to %d\n",
1602 STRING_DEFAULT_RANGE);
1603 m->str_range = STRING_DEFAULT_RANGE;
1604 return -1;
1605 }
1606 break;
1607 case FILE_REGEX:
1608 if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1609 file_magwarn(ms, "'/%c' not allowed on regex\n",
1610 CHAR_COMPACT_WHITESPACE);
1611 return -1;
1612 }
1613 if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1614 file_magwarn(ms, "'/%c' not allowed on regex\n",
1615 CHAR_COMPACT_OPTIONAL_WHITESPACE);
1616 return -1;
1617 }
1618 break;
1619 default:
1620 file_magwarn(ms, "coding error: m->type=%d\n",
1621 m->type);
1622 return -1;
1623 }
1624 return 0;
1625 }
1626
1627 private int
get_op(char c)1628 get_op(char c)
1629 {
1630 switch (c) {
1631 case '&':
1632 return FILE_OPAND;
1633 case '|':
1634 return FILE_OPOR;
1635 case '^':
1636 return FILE_OPXOR;
1637 case '+':
1638 return FILE_OPADD;
1639 case '-':
1640 return FILE_OPMINUS;
1641 case '*':
1642 return FILE_OPMULTIPLY;
1643 case '/':
1644 return FILE_OPDIVIDE;
1645 case '%':
1646 return FILE_OPMODULO;
1647 default:
1648 return -1;
1649 }
1650 }
1651
1652 #ifdef ENABLE_CONDITIONALS
1653 private int
get_cond(const char * l,const char ** t)1654 get_cond(const char *l, const char **t)
1655 {
1656 static const struct cond_tbl_s {
1657 char name[8];
1658 size_t len;
1659 int cond;
1660 } cond_tbl[] = {
1661 { "if", 2, COND_IF },
1662 { "elif", 4, COND_ELIF },
1663 { "else", 4, COND_ELSE },
1664 { "", 0, COND_NONE },
1665 };
1666 const struct cond_tbl_s *p;
1667
1668 for (p = cond_tbl; p->len; p++) {
1669 if (strncmp(l, p->name, p->len) == 0 &&
1670 isspace(CAST(unsigned char, l[p->len]))) {
1671 if (t)
1672 *t = l + p->len;
1673 break;
1674 }
1675 }
1676 return p->cond;
1677 }
1678
1679 private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1680 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1681 {
1682 int last_cond;
1683 last_cond = ms->c.li[cont_level].last_cond;
1684
1685 switch (cond) {
1686 case COND_IF:
1687 if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1688 if (ms->flags & MAGIC_CHECK)
1689 file_magwarn(ms, "syntax error: `if'");
1690 return -1;
1691 }
1692 last_cond = COND_IF;
1693 break;
1694
1695 case COND_ELIF:
1696 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1697 if (ms->flags & MAGIC_CHECK)
1698 file_magwarn(ms, "syntax error: `elif'");
1699 return -1;
1700 }
1701 last_cond = COND_ELIF;
1702 break;
1703
1704 case COND_ELSE:
1705 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1706 if (ms->flags & MAGIC_CHECK)
1707 file_magwarn(ms, "syntax error: `else'");
1708 return -1;
1709 }
1710 last_cond = COND_NONE;
1711 break;
1712
1713 case COND_NONE:
1714 last_cond = COND_NONE;
1715 break;
1716 }
1717
1718 ms->c.li[cont_level].last_cond = last_cond;
1719 return 0;
1720 }
1721 #endif /* ENABLE_CONDITIONALS */
1722
1723 private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1724 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1725 {
1726 const char *l = *lp;
1727
1728 while (!isspace(CAST(unsigned char, *++l)))
1729 switch (*l) {
1730 case CHAR_INDIRECT_RELATIVE:
1731 m->str_flags |= INDIRECT_RELATIVE;
1732 break;
1733 default:
1734 if (ms->flags & MAGIC_CHECK)
1735 file_magwarn(ms, "indirect modifier `%c' "
1736 "invalid", *l);
1737 *lp = l;
1738 return -1;
1739 }
1740 *lp = l;
1741 return 0;
1742 }
1743
1744 private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1745 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1746 int op)
1747 {
1748 const char *l = *lp;
1749 char *t;
1750 uint64_t val;
1751
1752 ++l;
1753 m->mask_op |= op;
1754 val = CAST(uint64_t, strtoull(l, &t, 0));
1755 l = t;
1756 m->num_mask = file_signextend(ms, m, val);
1757 eatsize(&l);
1758 *lp = l;
1759 }
1760
1761 private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1762 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1763 {
1764 const char *l = *lp;
1765 char *t;
1766 int have_range = 0;
1767
1768 while (!isspace(CAST(unsigned char, *++l))) {
1769 switch (*l) {
1770 case '0': case '1': case '2':
1771 case '3': case '4': case '5':
1772 case '6': case '7': case '8':
1773 case '9':
1774 if (have_range && (ms->flags & MAGIC_CHECK))
1775 file_magwarn(ms, "multiple ranges");
1776 have_range = 1;
1777 m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1778 if (m->str_range == 0)
1779 file_magwarn(ms, "zero range");
1780 l = t - 1;
1781 break;
1782 case CHAR_COMPACT_WHITESPACE:
1783 m->str_flags |= STRING_COMPACT_WHITESPACE;
1784 break;
1785 case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1786 m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1787 break;
1788 case CHAR_IGNORE_LOWERCASE:
1789 m->str_flags |= STRING_IGNORE_LOWERCASE;
1790 break;
1791 case CHAR_IGNORE_UPPERCASE:
1792 m->str_flags |= STRING_IGNORE_UPPERCASE;
1793 break;
1794 case CHAR_REGEX_OFFSET_START:
1795 m->str_flags |= REGEX_OFFSET_START;
1796 break;
1797 case CHAR_BINTEST:
1798 m->str_flags |= STRING_BINTEST;
1799 break;
1800 case CHAR_TEXTTEST:
1801 m->str_flags |= STRING_TEXTTEST;
1802 break;
1803 case CHAR_TRIM:
1804 m->str_flags |= STRING_TRIM;
1805 break;
1806 case CHAR_PSTRING_1_LE:
1807 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1808 if (m->type != FILE_PSTRING)
1809 goto bad;
1810 SET_LENGTH(PSTRING_1_LE);
1811 break;
1812 case CHAR_PSTRING_2_BE:
1813 if (m->type != FILE_PSTRING)
1814 goto bad;
1815 SET_LENGTH(PSTRING_2_BE);
1816 break;
1817 case CHAR_PSTRING_2_LE:
1818 if (m->type != FILE_PSTRING)
1819 goto bad;
1820 SET_LENGTH(PSTRING_2_LE);
1821 break;
1822 case CHAR_PSTRING_4_BE:
1823 if (m->type != FILE_PSTRING)
1824 goto bad;
1825 SET_LENGTH(PSTRING_4_BE);
1826 break;
1827 case CHAR_PSTRING_4_LE:
1828 switch (m->type) {
1829 case FILE_PSTRING:
1830 case FILE_REGEX:
1831 break;
1832 default:
1833 goto bad;
1834 }
1835 SET_LENGTH(PSTRING_4_LE);
1836 break;
1837 case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
1838 if (m->type != FILE_PSTRING)
1839 goto bad;
1840 m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
1841 break;
1842 default:
1843 bad:
1844 if (ms->flags & MAGIC_CHECK)
1845 file_magwarn(ms, "string modifier `%c' "
1846 "invalid", *l);
1847 goto out;
1848 }
1849 /* allow multiple '/' for readability */
1850 if (l[1] == '/' && !isspace(CAST(unsigned char, l[2])))
1851 l++;
1852 }
1853 if (string_modifier_check(ms, m) == -1)
1854 goto out;
1855 *lp = l;
1856 return 0;
1857 out:
1858 *lp = l;
1859 return -1;
1860 }
1861
1862 /*
1863 * parse one line from magic file, put into magic[index++] if valid
1864 */
1865 private int
parse(struct magic_set * ms,struct magic_entry * me,const char * line,size_t lineno,int action)1866 parse(struct magic_set *ms, struct magic_entry *me, const char *line,
1867 size_t lineno, int action)
1868 {
1869 #ifdef ENABLE_CONDITIONALS
1870 static uint32_t last_cont_level = 0;
1871 #endif
1872 size_t i;
1873 struct magic *m;
1874 const char *l = line;
1875 char *t;
1876 int op;
1877 uint32_t cont_level;
1878 int32_t diff;
1879
1880 cont_level = 0;
1881
1882 /*
1883 * Parse the offset.
1884 */
1885 while (*l == '>') {
1886 ++l; /* step over */
1887 cont_level++;
1888 }
1889 #ifdef ENABLE_CONDITIONALS
1890 if (cont_level == 0 || cont_level > last_cont_level)
1891 if (file_check_mem(ms, cont_level) == -1)
1892 return -1;
1893 last_cont_level = cont_level;
1894 #endif
1895 if (cont_level != 0) {
1896 if (me->mp == NULL) {
1897 file_magerror(ms, "No current entry for continuation");
1898 return -1;
1899 }
1900 if (me->cont_count == 0) {
1901 file_magerror(ms, "Continuations present with 0 count");
1902 return -1;
1903 }
1904 m = &me->mp[me->cont_count - 1];
1905 diff = CAST(int32_t, cont_level) - CAST(int32_t, m->cont_level);
1906 if (diff > 1)
1907 file_magwarn(ms, "New continuation level %u is more "
1908 "than one larger than current level %u", cont_level,
1909 m->cont_level);
1910 if (me->cont_count == me->max_count) {
1911 struct magic *nm;
1912 size_t cnt = me->max_count + ALLOC_CHUNK;
1913 if ((nm = CAST(struct magic *, realloc(me->mp,
1914 sizeof(*nm) * cnt))) == NULL) {
1915 file_oomem(ms, sizeof(*nm) * cnt);
1916 return -1;
1917 }
1918 me->mp = nm;
1919 me->max_count = CAST(uint32_t, cnt);
1920 }
1921 m = &me->mp[me->cont_count++];
1922 (void)memset(m, 0, sizeof(*m));
1923 m->cont_level = cont_level;
1924 } else {
1925 static const size_t len = sizeof(*m) * ALLOC_CHUNK;
1926 if (me->mp != NULL)
1927 return 1;
1928 if ((m = CAST(struct magic *, malloc(len))) == NULL) {
1929 file_oomem(ms, len);
1930 return -1;
1931 }
1932 me->mp = m;
1933 me->max_count = ALLOC_CHUNK;
1934 (void)memset(m, 0, sizeof(*m));
1935 m->factor_op = FILE_FACTOR_OP_NONE;
1936 m->cont_level = 0;
1937 me->cont_count = 1;
1938 }
1939 m->lineno = CAST(uint32_t, lineno);
1940
1941 if (*l == '&') { /* m->cont_level == 0 checked below. */
1942 ++l; /* step over */
1943 m->flag |= OFFADD;
1944 }
1945 if (*l == '(') {
1946 ++l; /* step over */
1947 m->flag |= INDIR;
1948 if (m->flag & OFFADD)
1949 m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
1950
1951 if (*l == '&') { /* m->cont_level == 0 checked below */
1952 ++l; /* step over */
1953 m->flag |= OFFADD;
1954 }
1955 }
1956 /* Indirect offsets are not valid at level 0. */
1957 if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) {
1958 if (ms->flags & MAGIC_CHECK)
1959 file_magwarn(ms, "relative offset at level 0");
1960 return -1;
1961 }
1962
1963 /* get offset, then skip over it */
1964 if (*l == '-') {
1965 ++l; /* step over */
1966 m->flag |= OFFNEGATIVE;
1967 }
1968 m->offset = CAST(int32_t, strtol(l, &t, 0));
1969 if (l == t) {
1970 if (ms->flags & MAGIC_CHECK)
1971 file_magwarn(ms, "offset `%s' invalid", l);
1972 return -1;
1973 }
1974
1975 l = t;
1976
1977 if (m->flag & INDIR) {
1978 m->in_type = FILE_LONG;
1979 m->in_offset = 0;
1980 m->in_op = 0;
1981 /*
1982 * read [.,lbs][+-]nnnnn)
1983 */
1984 if (*l == '.' || *l == ',') {
1985 if (*l == ',')
1986 m->in_op |= FILE_OPSIGNED;
1987 l++;
1988 switch (*l) {
1989 case 'l':
1990 m->in_type = FILE_LELONG;
1991 break;
1992 case 'L':
1993 m->in_type = FILE_BELONG;
1994 break;
1995 case 'm':
1996 m->in_type = FILE_MELONG;
1997 break;
1998 case 'h':
1999 case 's':
2000 m->in_type = FILE_LESHORT;
2001 break;
2002 case 'H':
2003 case 'S':
2004 m->in_type = FILE_BESHORT;
2005 break;
2006 case 'c':
2007 case 'b':
2008 case 'C':
2009 case 'B':
2010 m->in_type = FILE_BYTE;
2011 break;
2012 case 'e':
2013 case 'f':
2014 case 'g':
2015 m->in_type = FILE_LEDOUBLE;
2016 break;
2017 case 'E':
2018 case 'F':
2019 case 'G':
2020 m->in_type = FILE_BEDOUBLE;
2021 break;
2022 case 'i':
2023 m->in_type = FILE_LEID3;
2024 break;
2025 case 'I':
2026 m->in_type = FILE_BEID3;
2027 break;
2028 case 'q':
2029 m->in_type = FILE_LEQUAD;
2030 break;
2031 case 'Q':
2032 m->in_type = FILE_BEQUAD;
2033 break;
2034 default:
2035 if (ms->flags & MAGIC_CHECK)
2036 file_magwarn(ms,
2037 "indirect offset type `%c' invalid",
2038 *l);
2039 return -1;
2040 }
2041 l++;
2042 }
2043
2044 if (*l == '~') {
2045 m->in_op |= FILE_OPINVERSE;
2046 l++;
2047 }
2048 if ((op = get_op(*l)) != -1) {
2049 m->in_op |= op;
2050 l++;
2051 }
2052 if (*l == '(') {
2053 m->in_op |= FILE_OPINDIRECT;
2054 l++;
2055 }
2056 if (isdigit(CAST(unsigned char, *l)) || *l == '-') {
2057 m->in_offset = CAST(int32_t, strtol(l, &t, 0));
2058 if (l == t) {
2059 if (ms->flags & MAGIC_CHECK)
2060 file_magwarn(ms,
2061 "in_offset `%s' invalid", l);
2062 return -1;
2063 }
2064 l = t;
2065 }
2066 if (*l++ != ')' ||
2067 ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) {
2068 if (ms->flags & MAGIC_CHECK)
2069 file_magwarn(ms,
2070 "missing ')' in indirect offset");
2071 return -1;
2072 }
2073 }
2074 EATAB;
2075
2076 #ifdef ENABLE_CONDITIONALS
2077 m->cond = get_cond(l, &l);
2078 if (check_cond(ms, m->cond, cont_level) == -1)
2079 return -1;
2080
2081 EATAB;
2082 #endif
2083
2084 /*
2085 * Parse the type.
2086 */
2087 if (*l == 'u') {
2088 /*
2089 * Try it as a keyword type prefixed by "u"; match what
2090 * follows the "u". If that fails, try it as an SUS
2091 * integer type.
2092 */
2093 m->type = get_type(type_tbl, l + 1, &l);
2094 if (m->type == FILE_INVALID) {
2095 /*
2096 * Not a keyword type; parse it as an SUS type,
2097 * 'u' possibly followed by a number or C/S/L.
2098 */
2099 m->type = get_standard_integer_type(l, &l);
2100 }
2101 /* It's unsigned. */
2102 if (m->type != FILE_INVALID)
2103 m->flag |= UNSIGNED;
2104 } else {
2105 /*
2106 * Try it as a keyword type. If that fails, try it as
2107 * an SUS integer type if it begins with "d" or as an
2108 * SUS string type if it begins with "s". In any case,
2109 * it's not unsigned.
2110 */
2111 m->type = get_type(type_tbl, l, &l);
2112 if (m->type == FILE_INVALID) {
2113 /*
2114 * Not a keyword type; parse it as an SUS type,
2115 * either 'd' possibly followed by a number or
2116 * C/S/L, or just 's'.
2117 */
2118 if (*l == 'd')
2119 m->type = get_standard_integer_type(l, &l);
2120 else if (*l == 's'
2121 && !isalpha(CAST(unsigned char, l[1]))) {
2122 m->type = FILE_STRING;
2123 ++l;
2124 }
2125 }
2126 }
2127
2128 if (m->type == FILE_INVALID) {
2129 /* Not found - try it as a special keyword. */
2130 m->type = get_type(special_tbl, l, &l);
2131 }
2132
2133 if (m->type == FILE_INVALID) {
2134 if (ms->flags & MAGIC_CHECK)
2135 file_magwarn(ms, "type `%s' invalid", l);
2136 return -1;
2137 }
2138
2139 if (m->type == FILE_NAME && cont_level != 0) {
2140 if (ms->flags & MAGIC_CHECK)
2141 file_magwarn(ms, "`name%s' entries can only be "
2142 "declared at top level", l);
2143 return -1;
2144 }
2145
2146 /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2147 /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2148
2149 m->mask_op = 0;
2150 if (*l == '~') {
2151 if (!IS_STRING(m->type))
2152 m->mask_op |= FILE_OPINVERSE;
2153 else if (ms->flags & MAGIC_CHECK)
2154 file_magwarn(ms, "'~' invalid for string types");
2155 ++l;
2156 }
2157 m->str_range = 0;
2158 m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2159 if ((op = get_op(*l)) != -1) {
2160 if (IS_STRING(m->type)) {
2161 int r;
2162
2163 if (op != FILE_OPDIVIDE) {
2164 if (ms->flags & MAGIC_CHECK)
2165 file_magwarn(ms,
2166 "invalid string/indirect op: "
2167 "`%c'", *t);
2168 return -1;
2169 }
2170
2171 if (m->type == FILE_INDIRECT)
2172 r = parse_indirect_modifier(ms, m, &l);
2173 else
2174 r = parse_string_modifier(ms, m, &l);
2175 if (r == -1)
2176 return -1;
2177 } else
2178 parse_op_modifier(ms, m, &l, op);
2179 }
2180
2181 /*
2182 * We used to set mask to all 1's here, instead let's just not do
2183 * anything if mask = 0 (unless you have a better idea)
2184 */
2185 EATAB;
2186
2187 switch (*l) {
2188 case '>':
2189 case '<':
2190 m->reln = *l;
2191 ++l;
2192 if (*l == '=') {
2193 if (ms->flags & MAGIC_CHECK) {
2194 file_magwarn(ms, "%c= not supported",
2195 m->reln);
2196 return -1;
2197 }
2198 ++l;
2199 }
2200 break;
2201 /* Old-style anding: "0 byte &0x80 dynamically linked" */
2202 case '&':
2203 case '^':
2204 case '=':
2205 m->reln = *l;
2206 ++l;
2207 if (*l == '=') {
2208 /* HP compat: ignore &= etc. */
2209 ++l;
2210 }
2211 break;
2212 case '!':
2213 m->reln = *l;
2214 ++l;
2215 break;
2216 default:
2217 m->reln = '='; /* the default relation */
2218 if (*l == 'x' && ((isascii(CAST(unsigned char, l[1])) &&
2219 isspace(CAST(unsigned char, l[1]))) || !l[1])) {
2220 m->reln = *l;
2221 ++l;
2222 }
2223 break;
2224 }
2225 /*
2226 * Grab the value part, except for an 'x' reln.
2227 */
2228 if (m->reln != 'x' && getvalue(ms, m, &l, action))
2229 return -1;
2230
2231 /*
2232 * TODO finish this macro and start using it!
2233 * #define offsetcheck {if (offset > ms->bytes_max -1)
2234 * magwarn("offset too big"); }
2235 */
2236
2237 /*
2238 * Now get last part - the description
2239 */
2240 EATAB;
2241 if (l[0] == '\b') {
2242 ++l;
2243 m->flag |= NOSPACE;
2244 } else if ((l[0] == '\\') && (l[1] == 'b')) {
2245 ++l;
2246 ++l;
2247 m->flag |= NOSPACE;
2248 }
2249 for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); )
2250 continue;
2251 if (i == sizeof(m->desc)) {
2252 m->desc[sizeof(m->desc) - 1] = '\0';
2253 if (ms->flags & MAGIC_CHECK)
2254 file_magwarn(ms, "description `%s' truncated", m->desc);
2255 }
2256
2257 /*
2258 * We only do this check while compiling, or if any of the magic
2259 * files were not compiled.
2260 */
2261 if (ms->flags & MAGIC_CHECK) {
2262 if (check_format(ms, m) == -1)
2263 return -1;
2264 }
2265 #ifndef COMPILE_ONLY
2266 if (action == FILE_CHECK) {
2267 file_mdump(m);
2268 }
2269 #endif
2270 m->mimetype[0] = '\0'; /* initialise MIME type to none */
2271 return 0;
2272 }
2273
2274 /*
2275 * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2276 * if valid
2277 */
2278 private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2279 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line,
2280 size_t len __attribute__((__unused__)))
2281 {
2282 const char *l = line;
2283 char *el;
2284 unsigned long factor;
2285 struct magic *m = &me->mp[0];
2286
2287 if (m->factor_op != FILE_FACTOR_OP_NONE) {
2288 file_magwarn(ms,
2289 "Current entry already has a strength type: %c %d",
2290 m->factor_op, m->factor);
2291 return -1;
2292 }
2293 if (m->type == FILE_NAME) {
2294 file_magwarn(ms, "%s: Strength setting is not supported in "
2295 "\"name\" magic entries", m->value.s);
2296 return -1;
2297 }
2298 EATAB;
2299 switch (*l) {
2300 case FILE_FACTOR_OP_NONE:
2301 case FILE_FACTOR_OP_PLUS:
2302 case FILE_FACTOR_OP_MINUS:
2303 case FILE_FACTOR_OP_TIMES:
2304 case FILE_FACTOR_OP_DIV:
2305 m->factor_op = *l++;
2306 break;
2307 default:
2308 file_magwarn(ms, "Unknown factor op `%c'", *l);
2309 return -1;
2310 }
2311 EATAB;
2312 factor = strtoul(l, &el, 0);
2313 if (factor > 255) {
2314 file_magwarn(ms, "Too large factor `%lu'", factor);
2315 goto out;
2316 }
2317 if (*el && !isspace(CAST(unsigned char, *el))) {
2318 file_magwarn(ms, "Bad factor `%s'", l);
2319 goto out;
2320 }
2321 m->factor = CAST(uint8_t, factor);
2322 if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2323 file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2324 m->factor_op, m->factor);
2325 goto out;
2326 }
2327 return 0;
2328 out:
2329 m->factor_op = FILE_FACTOR_OP_NONE;
2330 m->factor = 0;
2331 return -1;
2332 }
2333
2334 private int
goodchar(unsigned char x,const char * extra)2335 goodchar(unsigned char x, const char *extra)
2336 {
2337 return (isascii(x) && isalnum(x)) || strchr(extra, x);
2338 }
2339
2340 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)2341 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2342 size_t llen, off_t off, size_t len, const char *name, const char *extra,
2343 int nt)
2344 {
2345 size_t i;
2346 const char *l = line;
2347 struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2348 char *buf = CAST(char *, CAST(void *, m)) + off;
2349
2350 if (buf[0] != '\0') {
2351 len = nt ? strlen(buf) : len;
2352 file_magwarn(ms, "Current entry already has a %s type "
2353 "`%.*s', new type `%s'", name, CAST(int, len), buf, l);
2354 return -1;
2355 }
2356
2357 if (*m->desc == '\0') {
2358 file_magwarn(ms, "Current entry does not yet have a "
2359 "description for adding a %s type", name);
2360 return -1;
2361 }
2362
2363 EATAB;
2364 for (i = 0; *l && i < llen && i < len && goodchar(*l, extra);
2365 buf[i++] = *l++)
2366 continue;
2367
2368 if (i == len && *l) {
2369 if (nt)
2370 buf[len - 1] = '\0';
2371 if (ms->flags & MAGIC_CHECK)
2372 file_magwarn(ms, "%s type `%s' truncated %"
2373 SIZE_T_FORMAT "u", name, line, i);
2374 } else {
2375 if (!isspace(CAST(unsigned char, *l)) && !goodchar(*l, extra))
2376 file_magwarn(ms, "%s type `%s' has bad char '%c'",
2377 name, line, *l);
2378 if (nt)
2379 buf[i] = '\0';
2380 }
2381
2382 if (i > 0)
2383 return 0;
2384
2385 file_magerror(ms, "Bad magic entry '%s'", line);
2386 return -1;
2387 }
2388
2389 /*
2390 * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2391 * magic[index - 1]
2392 */
2393 private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2394 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line,
2395 size_t len)
2396 {
2397 struct magic *m = &me->mp[0];
2398
2399 return parse_extra(ms, me, line, len,
2400 CAST(off_t, offsetof(struct magic, apple)),
2401 sizeof(m->apple), "APPLE", "!+-./?", 0);
2402 }
2403
2404 /*
2405 * Parse a comma-separated list of extensions
2406 */
2407 private int
parse_ext(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2408 parse_ext(struct magic_set *ms, struct magic_entry *me, const char *line,
2409 size_t len)
2410 {
2411 struct magic *m = &me->mp[0];
2412
2413 return parse_extra(ms, me, line, len,
2414 CAST(off_t, offsetof(struct magic, ext)),
2415 sizeof(m->ext), "EXTENSION", ",!+-/@?_$", 0);
2416 }
2417
2418 /*
2419 * parse a MIME annotation line from magic file, put into magic[index - 1]
2420 * if valid
2421 */
2422 private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line,size_t len)2423 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line,
2424 size_t len)
2425 {
2426 struct magic *m = &me->mp[0];
2427
2428 return parse_extra(ms, me, line, len,
2429 CAST(off_t, offsetof(struct magic, mimetype)),
2430 sizeof(m->mimetype), "MIME", "+-/.$?:{}", 1);
2431 }
2432
2433 private int
check_format_type(const char * ptr,int type,const char ** estr)2434 check_format_type(const char *ptr, int type, const char **estr)
2435 {
2436 int quad = 0, h;
2437 size_t len, cnt;
2438 if (*ptr == '\0') {
2439 /* Missing format string; bad */
2440 *estr = "missing format spec";
2441 return -1;
2442 }
2443
2444 switch (file_formats[type]) {
2445 case FILE_FMT_QUAD:
2446 quad = 1;
2447 /*FALLTHROUGH*/
2448 case FILE_FMT_NUM:
2449 if (quad == 0) {
2450 switch (type) {
2451 case FILE_BYTE:
2452 h = 2;
2453 break;
2454 case FILE_SHORT:
2455 case FILE_BESHORT:
2456 case FILE_LESHORT:
2457 h = 1;
2458 break;
2459 case FILE_LONG:
2460 case FILE_BELONG:
2461 case FILE_LELONG:
2462 case FILE_MELONG:
2463 case FILE_LEID3:
2464 case FILE_BEID3:
2465 case FILE_INDIRECT:
2466 h = 0;
2467 break;
2468 default:
2469 abort();
2470 }
2471 } else
2472 h = 0;
2473 if (*ptr == '-')
2474 ptr++;
2475 if (*ptr == '.')
2476 ptr++;
2477 if (*ptr == '#')
2478 ptr++;
2479 #define CHECKLEN() do { \
2480 for (len = cnt = 0; isdigit(CAST(unsigned char, *ptr)); ptr++, cnt++) \
2481 len = len * 10 + (*ptr - '0'); \
2482 if (cnt > 5 || len > 1024) \
2483 goto toolong; \
2484 } while (/*CONSTCOND*/0)
2485
2486 CHECKLEN();
2487 if (*ptr == '.')
2488 ptr++;
2489 CHECKLEN();
2490 if (quad) {
2491 if (*ptr++ != 'l')
2492 goto invalid;
2493 if (*ptr++ != 'l')
2494 goto invalid;
2495 }
2496
2497 switch (*ptr++) {
2498 #ifdef STRICT_FORMAT /* "long" formats are int formats for us */
2499 /* so don't accept the 'l' modifier */
2500 case 'l':
2501 switch (*ptr++) {
2502 case 'i':
2503 case 'd':
2504 case 'u':
2505 case 'o':
2506 case 'x':
2507 case 'X':
2508 if (h == 0)
2509 return 0;
2510 /*FALLTHROUGH*/
2511 default:
2512 goto invalid;
2513 }
2514
2515 /*
2516 * Don't accept h and hh modifiers. They make writing
2517 * magic entries more complicated, for very little benefit
2518 */
2519 case 'h':
2520 if (h-- <= 0)
2521 goto invalid;
2522 switch (*ptr++) {
2523 case 'h':
2524 if (h-- <= 0)
2525 goto invalid;
2526 switch (*ptr++) {
2527 case 'i':
2528 case 'd':
2529 case 'u':
2530 case 'o':
2531 case 'x':
2532 case 'X':
2533 return 0;
2534 default:
2535 goto invalid;
2536 }
2537 case 'i':
2538 case 'd':
2539 case 'u':
2540 case 'o':
2541 case 'x':
2542 case 'X':
2543 if (h == 0)
2544 return 0;
2545 /*FALLTHROUGH*/
2546 default:
2547 goto invalid;
2548 }
2549 #endif
2550 case 'c':
2551 if (h == 2)
2552 return 0;
2553 goto invalid;
2554 case 'i':
2555 case 'd':
2556 case 'u':
2557 case 'o':
2558 case 'x':
2559 case 'X':
2560 #ifdef STRICT_FORMAT
2561 if (h == 0)
2562 return 0;
2563 /*FALLTHROUGH*/
2564 #else
2565 return 0;
2566 #endif
2567 default:
2568 goto invalid;
2569 }
2570
2571 case FILE_FMT_FLOAT:
2572 case FILE_FMT_DOUBLE:
2573 if (*ptr == '-')
2574 ptr++;
2575 if (*ptr == '.')
2576 ptr++;
2577 CHECKLEN();
2578 if (*ptr == '.')
2579 ptr++;
2580 CHECKLEN();
2581 switch (*ptr++) {
2582 case 'e':
2583 case 'E':
2584 case 'f':
2585 case 'F':
2586 case 'g':
2587 case 'G':
2588 return 0;
2589
2590 default:
2591 goto invalid;
2592 }
2593
2594
2595 case FILE_FMT_STR:
2596 if (*ptr == '-')
2597 ptr++;
2598 while (isdigit(CAST(unsigned char, *ptr)))
2599 ptr++;
2600 if (*ptr == '.') {
2601 ptr++;
2602 while (isdigit(CAST(unsigned char , *ptr)))
2603 ptr++;
2604 }
2605
2606 switch (*ptr++) {
2607 case 's':
2608 return 0;
2609 default:
2610 goto invalid;
2611 }
2612
2613 default:
2614 /* internal error */
2615 abort();
2616 }
2617 invalid:
2618 *estr = "not valid";
2619 toolong:
2620 *estr = "too long";
2621 return -1;
2622 }
2623
2624 /*
2625 * Check that the optional printf format in description matches
2626 * the type of the magic.
2627 */
2628 private int
check_format(struct magic_set * ms,struct magic * m)2629 check_format(struct magic_set *ms, struct magic *m)
2630 {
2631 char *ptr;
2632 const char *estr;
2633
2634 for (ptr = m->desc; *ptr; ptr++)
2635 if (*ptr == '%')
2636 break;
2637 if (*ptr == '\0') {
2638 /* No format string; ok */
2639 return 1;
2640 }
2641
2642 assert(file_nformats == file_nnames);
2643
2644 if (m->type >= file_nformats) {
2645 file_magwarn(ms, "Internal error inconsistency between "
2646 "m->type and format strings");
2647 return -1;
2648 }
2649 if (file_formats[m->type] == FILE_FMT_NONE) {
2650 file_magwarn(ms, "No format string for `%s' with description "
2651 "`%s'", m->desc, file_names[m->type]);
2652 return -1;
2653 }
2654
2655 ptr++;
2656 if (check_format_type(ptr, m->type, &estr) == -1) {
2657 /*
2658 * TODO: this error message is unhelpful if the format
2659 * string is not one character long
2660 */
2661 file_magwarn(ms, "Printf format is %s for type "
2662 "`%s' in description `%s'", estr,
2663 file_names[m->type], m->desc);
2664 return -1;
2665 }
2666
2667 for (; *ptr; ptr++) {
2668 if (*ptr == '%') {
2669 file_magwarn(ms,
2670 "Too many format strings (should have at most one) "
2671 "for `%s' with description `%s'",
2672 file_names[m->type], m->desc);
2673 return -1;
2674 }
2675 }
2676 return 0;
2677 }
2678
2679 /*
2680 * Read a numeric value from a pointer, into the value union of a magic
2681 * pointer, according to the magic type. Update the string pointer to point
2682 * just after the number read. Return 0 for success, non-zero for failure.
2683 */
2684 private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2685 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2686 {
2687 char *ep;
2688 uint64_t ull;
2689
2690 switch (m->type) {
2691 case FILE_BESTRING16:
2692 case FILE_LESTRING16:
2693 case FILE_STRING:
2694 case FILE_PSTRING:
2695 case FILE_REGEX:
2696 case FILE_SEARCH:
2697 case FILE_NAME:
2698 case FILE_USE:
2699 case FILE_DER:
2700 *p = getstr(ms, m, *p, action == FILE_COMPILE);
2701 if (*p == NULL) {
2702 if (ms->flags & MAGIC_CHECK)
2703 file_magwarn(ms, "cannot get string from `%s'",
2704 m->value.s);
2705 return -1;
2706 }
2707 if (m->type == FILE_REGEX) {
2708 file_regex_t rx;
2709 int rc = file_regcomp(&rx, m->value.s, REG_EXTENDED);
2710 if (rc) {
2711 if (ms->flags & MAGIC_CHECK)
2712 file_regerror(&rx, rc, ms);
2713 }
2714 file_regfree(&rx);
2715 return rc ? -1 : 0;
2716 }
2717 return 0;
2718 default:
2719 if (m->reln == 'x')
2720 return 0;
2721 break;
2722 }
2723
2724 switch (m->type) {
2725 case FILE_FLOAT:
2726 case FILE_BEFLOAT:
2727 case FILE_LEFLOAT:
2728 errno = 0;
2729 #ifdef HAVE_STRTOF
2730 m->value.f = strtof(*p, &ep);
2731 #else
2732 m->value.f = (float)strtod(*p, &ep);
2733 #endif
2734 if (errno == 0)
2735 *p = ep;
2736 return 0;
2737 case FILE_DOUBLE:
2738 case FILE_BEDOUBLE:
2739 case FILE_LEDOUBLE:
2740 errno = 0;
2741 m->value.d = strtod(*p, &ep);
2742 if (errno == 0)
2743 *p = ep;
2744 return 0;
2745 case FILE_GUID:
2746 if (file_parse_guid(*p, m->value.guid) == -1)
2747 return -1;
2748 *p += FILE_GUID_SIZE - 1;
2749 return 0;
2750 default:
2751 errno = 0;
2752 ull = CAST(uint64_t, strtoull(*p, &ep, 0));
2753 m->value.q = file_signextend(ms, m, ull);
2754 if (*p == ep) {
2755 file_magwarn(ms, "Unparsable number `%s'", *p);
2756 } else {
2757 size_t ts = typesize(m->type);
2758 uint64_t x;
2759 const char *q;
2760
2761 if (ts == FILE_BADSIZE) {
2762 file_magwarn(ms,
2763 "Expected numeric type got `%s'",
2764 type_tbl[m->type].name);
2765 }
2766 for (q = *p; isspace(CAST(unsigned char, *q)); q++)
2767 continue;
2768 if (*q == '-')
2769 ull = -CAST(int64_t, ull);
2770 switch (ts) {
2771 case 1:
2772 x = CAST(uint64_t, ull & ~0xffULL);
2773 break;
2774 case 2:
2775 x = CAST(uint64_t, ull & ~0xffffULL);
2776 break;
2777 case 4:
2778 x = CAST(uint64_t, ull & ~0xffffffffULL);
2779 break;
2780 case 8:
2781 x = 0;
2782 break;
2783 default:
2784 abort();
2785 }
2786 if (x) {
2787 file_magwarn(ms, "Overflow for numeric"
2788 " type `%s' value %#" PRIx64,
2789 type_tbl[m->type].name, ull);
2790 }
2791 }
2792 if (errno == 0) {
2793 *p = ep;
2794 eatsize(p);
2795 }
2796 return 0;
2797 }
2798 }
2799
2800 /*
2801 * Convert a string containing C character escapes. Stop at an unescaped
2802 * space or tab.
2803 * Copy the converted version to "m->value.s", and the length in m->vallen.
2804 * Return updated scan pointer as function result. Warn if set.
2805 */
2806 private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)2807 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
2808 {
2809 const char *origs = s;
2810 char *p = m->value.s;
2811 size_t plen = sizeof(m->value.s);
2812 char *origp = p;
2813 char *pmax = p + plen - 1;
2814 int c;
2815 int val;
2816
2817 while ((c = *s++) != '\0') {
2818 if (isspace(CAST(unsigned char, c)))
2819 break;
2820 if (p >= pmax) {
2821 file_error(ms, 0, "string too long: `%s'", origs);
2822 return NULL;
2823 }
2824 if (c == '\\') {
2825 switch(c = *s++) {
2826
2827 case '\0':
2828 if (warn)
2829 file_magwarn(ms, "incomplete escape");
2830 s--;
2831 goto out;
2832
2833 case '\t':
2834 if (warn) {
2835 file_magwarn(ms,
2836 "escaped tab found, use \\t instead");
2837 warn = 0; /* already did */
2838 }
2839 /*FALLTHROUGH*/
2840 default:
2841 if (warn) {
2842 if (isprint(CAST(unsigned char, c))) {
2843 /* Allow escaping of
2844 * ``relations'' */
2845 if (strchr("<>&^=!", c) == NULL
2846 && (m->type != FILE_REGEX ||
2847 strchr("[]().*?^$|{}", c)
2848 == NULL)) {
2849 file_magwarn(ms, "no "
2850 "need to escape "
2851 "`%c'", c);
2852 }
2853 } else {
2854 file_magwarn(ms,
2855 "unknown escape sequence: "
2856 "\\%03o", c);
2857 }
2858 }
2859 /*FALLTHROUGH*/
2860 /* space, perhaps force people to use \040? */
2861 case ' ':
2862 #if 0
2863 /*
2864 * Other things people escape, but shouldn't need to,
2865 * so we disallow them
2866 */
2867 case '\'':
2868 case '"':
2869 case '?':
2870 #endif
2871 /* Relations */
2872 case '>':
2873 case '<':
2874 case '&':
2875 case '^':
2876 case '=':
2877 case '!':
2878 /* and baskslash itself */
2879 case '\\':
2880 *p++ = CAST(char, c);
2881 break;
2882
2883 case 'a':
2884 *p++ = '\a';
2885 break;
2886
2887 case 'b':
2888 *p++ = '\b';
2889 break;
2890
2891 case 'f':
2892 *p++ = '\f';
2893 break;
2894
2895 case 'n':
2896 *p++ = '\n';
2897 break;
2898
2899 case 'r':
2900 *p++ = '\r';
2901 break;
2902
2903 case 't':
2904 *p++ = '\t';
2905 break;
2906
2907 case 'v':
2908 *p++ = '\v';
2909 break;
2910
2911 /* \ and up to 3 octal digits */
2912 case '0':
2913 case '1':
2914 case '2':
2915 case '3':
2916 case '4':
2917 case '5':
2918 case '6':
2919 case '7':
2920 val = c - '0';
2921 c = *s++; /* try for 2 */
2922 if (c >= '0' && c <= '7') {
2923 val = (val << 3) | (c - '0');
2924 c = *s++; /* try for 3 */
2925 if (c >= '0' && c <= '7')
2926 val = (val << 3) | (c-'0');
2927 else
2928 --s;
2929 }
2930 else
2931 --s;
2932 *p++ = CAST(char, val);
2933 break;
2934
2935 /* \x and up to 2 hex digits */
2936 case 'x':
2937 val = 'x'; /* Default if no digits */
2938 c = hextoint(*s++); /* Get next char */
2939 if (c >= 0) {
2940 val = c;
2941 c = hextoint(*s++);
2942 if (c >= 0)
2943 val = (val << 4) + c;
2944 else
2945 --s;
2946 } else
2947 --s;
2948 *p++ = CAST(char, val);
2949 break;
2950 }
2951 } else
2952 *p++ = CAST(char, c);
2953 }
2954 --s;
2955 out:
2956 *p = '\0';
2957 m->vallen = CAST(unsigned char, (p - origp));
2958 if (m->type == FILE_PSTRING) {
2959 size_t l = file_pstring_length_size(ms, m);
2960 if (l == FILE_BADSIZE)
2961 return NULL;
2962 m->vallen += CAST(unsigned char, l);
2963 }
2964 return s;
2965 }
2966
2967
2968 /* Single hex char to int; -1 if not a hex char. */
2969 private int
hextoint(int c)2970 hextoint(int c)
2971 {
2972 if (!isascii(CAST(unsigned char, c)))
2973 return -1;
2974 if (isdigit(CAST(unsigned char, c)))
2975 return c - '0';
2976 if ((c >= 'a') && (c <= 'f'))
2977 return c + 10 - 'a';
2978 if (( c>= 'A') && (c <= 'F'))
2979 return c + 10 - 'A';
2980 return -1;
2981 }
2982
2983
2984 /*
2985 * Print a string containing C character escapes.
2986 */
2987 protected void
file_showstr(FILE * fp,const char * s,size_t len)2988 file_showstr(FILE *fp, const char *s, size_t len)
2989 {
2990 char c;
2991
2992 for (;;) {
2993 if (len == FILE_BADSIZE) {
2994 c = *s++;
2995 if (c == '\0')
2996 break;
2997 }
2998 else {
2999 if (len-- == 0)
3000 break;
3001 c = *s++;
3002 }
3003 if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */
3004 (void) fputc(c, fp);
3005 else {
3006 (void) fputc('\\', fp);
3007 switch (c) {
3008 case '\a':
3009 (void) fputc('a', fp);
3010 break;
3011
3012 case '\b':
3013 (void) fputc('b', fp);
3014 break;
3015
3016 case '\f':
3017 (void) fputc('f', fp);
3018 break;
3019
3020 case '\n':
3021 (void) fputc('n', fp);
3022 break;
3023
3024 case '\r':
3025 (void) fputc('r', fp);
3026 break;
3027
3028 case '\t':
3029 (void) fputc('t', fp);
3030 break;
3031
3032 case '\v':
3033 (void) fputc('v', fp);
3034 break;
3035
3036 default:
3037 (void) fprintf(fp, "%.3o", c & 0377);
3038 break;
3039 }
3040 }
3041 }
3042 }
3043
3044 /*
3045 * eatsize(): Eat the size spec from a number [eg. 10UL]
3046 */
3047 private void
eatsize(const char ** p)3048 eatsize(const char **p)
3049 {
3050 const char *l = *p;
3051
3052 if (LOWCASE(*l) == 'u')
3053 l++;
3054
3055 switch (LOWCASE(*l)) {
3056 case 'l': /* long */
3057 case 's': /* short */
3058 case 'h': /* short */
3059 case 'b': /* char/byte */
3060 case 'c': /* char/byte */
3061 l++;
3062 /*FALLTHROUGH*/
3063 default:
3064 break;
3065 }
3066
3067 *p = l;
3068 }
3069
3070 /*
3071 * handle a buffer containing a compiled file.
3072 */
3073 private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)3074 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
3075 {
3076 struct magic_map *map;
3077
3078 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3079 file_oomem(ms, sizeof(*map));
3080 return NULL;
3081 }
3082 map->len = len;
3083 map->p = buf;
3084 map->type = MAP_TYPE_USER;
3085 if (check_buffer(ms, map, "buffer") != 0) {
3086 apprentice_unmap(map);
3087 return NULL;
3088 }
3089 return map;
3090 }
3091
3092 /*
3093 * handle a compiled file.
3094 */
3095
3096 private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)3097 apprentice_map(struct magic_set *ms, const char *fn)
3098 {
3099 int fd;
3100 struct stat st;
3101 char *dbname = NULL;
3102 struct magic_map *map;
3103 struct magic_map *rv = NULL;
3104
3105 fd = -1;
3106 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3107 file_oomem(ms, sizeof(*map));
3108 goto error;
3109 }
3110 map->type = MAP_TYPE_USER; /* unspecified */
3111
3112 dbname = mkdbname(ms, fn, 0);
3113 if (dbname == NULL)
3114 goto error;
3115
3116 if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
3117 goto error;
3118
3119 if (fstat(fd, &st) == -1) {
3120 file_error(ms, errno, "cannot stat `%s'", dbname);
3121 goto error;
3122 }
3123 if (st.st_size < 8 || st.st_size > maxoff_t()) {
3124 file_error(ms, 0, "file `%s' is too %s", dbname,
3125 st.st_size < 8 ? "small" : "large");
3126 goto error;
3127 }
3128
3129 map->len = CAST(size_t, st.st_size);
3130 #ifdef QUICK
3131 map->type = MAP_TYPE_MMAP;
3132 if ((map->p = mmap(0, CAST(size_t, st.st_size), PROT_READ|PROT_WRITE,
3133 MAP_PRIVATE|MAP_FILE, fd, CAST(off_t, 0))) == MAP_FAILED) {
3134 file_error(ms, errno, "cannot map `%s'", dbname);
3135 goto error;
3136 }
3137 #else
3138 map->type = MAP_TYPE_MALLOC;
3139 if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
3140 file_oomem(ms, map->len);
3141 goto error;
3142 }
3143 if (read(fd, map->p, map->len) != (ssize_t)map->len) {
3144 file_badread(ms);
3145 goto error;
3146 }
3147 #endif
3148 (void)close(fd);
3149 fd = -1;
3150
3151 if (check_buffer(ms, map, dbname) != 0) {
3152 goto error;
3153 }
3154 #ifdef QUICK
3155 if (mprotect(map->p, CAST(size_t, st.st_size), PROT_READ) == -1) {
3156 file_error(ms, errno, "cannot mprotect `%s'", dbname);
3157 goto error;
3158 }
3159 #endif
3160
3161 free(dbname);
3162 return map;
3163
3164 error:
3165 if (fd != -1)
3166 (void)close(fd);
3167 apprentice_unmap(map);
3168 free(dbname);
3169 return rv;
3170 }
3171
3172 private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)3173 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
3174 {
3175 uint32_t *ptr;
3176 uint32_t entries, nentries;
3177 uint32_t version;
3178 int i, needsbyteswap;
3179
3180 ptr = CAST(uint32_t *, map->p);
3181 if (*ptr != MAGICNO) {
3182 if (swap4(*ptr) != MAGICNO) {
3183 file_error(ms, 0, "bad magic in `%s'", dbname);
3184 return -1;
3185 }
3186 needsbyteswap = 1;
3187 } else
3188 needsbyteswap = 0;
3189 if (needsbyteswap)
3190 version = swap4(ptr[1]);
3191 else
3192 version = ptr[1];
3193 if (version != VERSIONNO) {
3194 file_error(ms, 0, "File %s supports only version %d magic "
3195 "files. `%s' is version %d", VERSION,
3196 VERSIONNO, dbname, version);
3197 return -1;
3198 }
3199 entries = CAST(uint32_t, map->len / sizeof(struct magic));
3200 if ((entries * sizeof(struct magic)) != map->len) {
3201 file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
3202 "a multiple of %" SIZE_T_FORMAT "u",
3203 dbname, map->len, sizeof(struct magic));
3204 return -1;
3205 }
3206 map->magic[0] = CAST(struct magic *, map->p) + 1;
3207 nentries = 0;
3208 for (i = 0; i < MAGIC_SETS; i++) {
3209 if (needsbyteswap)
3210 map->nmagic[i] = swap4(ptr[i + 2]);
3211 else
3212 map->nmagic[i] = ptr[i + 2];
3213 if (i != MAGIC_SETS - 1)
3214 map->magic[i + 1] = map->magic[i] + map->nmagic[i];
3215 nentries += map->nmagic[i];
3216 }
3217 if (entries != nentries + 1) {
3218 file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
3219 dbname, entries, nentries + 1);
3220 return -1;
3221 }
3222 if (needsbyteswap)
3223 for (i = 0; i < MAGIC_SETS; i++)
3224 byteswap(map->magic[i], map->nmagic[i]);
3225 return 0;
3226 }
3227
3228 /*
3229 * handle an mmaped file.
3230 */
3231 private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)3232 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
3233 {
3234 static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
3235 static const size_t m = sizeof(**map->magic);
3236 int fd = -1;
3237 size_t len;
3238 char *dbname;
3239 int rv = -1;
3240 uint32_t i;
3241 union {
3242 struct magic m;
3243 uint32_t h[2 + MAGIC_SETS];
3244 } hdr;
3245
3246 dbname = mkdbname(ms, fn, 1);
3247
3248 if (dbname == NULL)
3249 goto out;
3250
3251 if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
3252 {
3253 file_error(ms, errno, "cannot open `%s'", dbname);
3254 goto out;
3255 }
3256 memset(&hdr, 0, sizeof(hdr));
3257 hdr.h[0] = MAGICNO;
3258 hdr.h[1] = VERSIONNO;
3259 memcpy(hdr.h + 2, map->nmagic, nm);
3260
3261 if (write(fd, &hdr, sizeof(hdr)) != CAST(ssize_t, sizeof(hdr))) {
3262 file_error(ms, errno, "error writing `%s'", dbname);
3263 goto out2;
3264 }
3265
3266 for (i = 0; i < MAGIC_SETS; i++) {
3267 len = m * map->nmagic[i];
3268 if (write(fd, map->magic[i], len) != CAST(ssize_t, len)) {
3269 file_error(ms, errno, "error writing `%s'", dbname);
3270 goto out2;
3271 }
3272 }
3273
3274 rv = 0;
3275 out2:
3276 if (fd != -1)
3277 (void)close(fd);
3278 out:
3279 apprentice_unmap(map);
3280 free(dbname);
3281 return rv;
3282 }
3283
3284 private const char ext[] = ".mgc";
3285 /*
3286 * make a dbname
3287 */
3288 private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3289 mkdbname(struct magic_set *ms, const char *fn, int strip)
3290 {
3291 const char *p, *q;
3292 char *buf;
3293
3294 if (strip) {
3295 if ((p = strrchr(fn, '/')) != NULL)
3296 fn = ++p;
3297 }
3298
3299 for (q = fn; *q; q++)
3300 continue;
3301 /* Look for .mgc */
3302 for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3303 if (*p != *q)
3304 break;
3305
3306 /* Did not find .mgc, restore q */
3307 if (p >= ext)
3308 while (*q)
3309 q++;
3310
3311 q++;
3312 /* Compatibility with old code that looked in .mime */
3313 if (ms->flags & MAGIC_MIME) {
3314 if (asprintf(&buf, "%.*s.mime%s", CAST(int, q - fn), fn, ext)
3315 < 0)
3316 return NULL;
3317 if (access(buf, R_OK) != -1) {
3318 ms->flags &= MAGIC_MIME_TYPE;
3319 return buf;
3320 }
3321 free(buf);
3322 }
3323 if (asprintf(&buf, "%.*s%s", CAST(int, q - fn), fn, ext) < 0)
3324 return NULL;
3325
3326 /* Compatibility with old code that looked in .mime */
3327 if (strstr(fn, ".mime") != NULL)
3328 ms->flags &= MAGIC_MIME_TYPE;
3329 return buf;
3330 }
3331
3332 /*
3333 * Byteswap an mmap'ed file if needed
3334 */
3335 private void
byteswap(struct magic * magic,uint32_t nmagic)3336 byteswap(struct magic *magic, uint32_t nmagic)
3337 {
3338 uint32_t i;
3339 for (i = 0; i < nmagic; i++)
3340 bs1(&magic[i]);
3341 }
3342
3343 /*
3344 * swap a short
3345 */
3346 private uint16_t
swap2(uint16_t sv)3347 swap2(uint16_t sv)
3348 {
3349 uint16_t rv;
3350 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3351 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3352 d[0] = s[1];
3353 d[1] = s[0];
3354 return rv;
3355 }
3356
3357 /*
3358 * swap an int
3359 */
3360 private uint32_t
swap4(uint32_t sv)3361 swap4(uint32_t sv)
3362 {
3363 uint32_t rv;
3364 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3365 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3366 d[0] = s[3];
3367 d[1] = s[2];
3368 d[2] = s[1];
3369 d[3] = s[0];
3370 return rv;
3371 }
3372
3373 /*
3374 * swap a quad
3375 */
3376 private uint64_t
swap8(uint64_t sv)3377 swap8(uint64_t sv)
3378 {
3379 uint64_t rv;
3380 uint8_t *s = RCAST(uint8_t *, RCAST(void *, &sv));
3381 uint8_t *d = RCAST(uint8_t *, RCAST(void *, &rv));
3382 #if 0
3383 d[0] = s[3];
3384 d[1] = s[2];
3385 d[2] = s[1];
3386 d[3] = s[0];
3387 d[4] = s[7];
3388 d[5] = s[6];
3389 d[6] = s[5];
3390 d[7] = s[4];
3391 #else
3392 d[0] = s[7];
3393 d[1] = s[6];
3394 d[2] = s[5];
3395 d[3] = s[4];
3396 d[4] = s[3];
3397 d[5] = s[2];
3398 d[6] = s[1];
3399 d[7] = s[0];
3400 #endif
3401 return rv;
3402 }
3403
3404 /*
3405 * byteswap a single magic entry
3406 */
3407 private void
bs1(struct magic * m)3408 bs1(struct magic *m)
3409 {
3410 m->cont_level = swap2(m->cont_level);
3411 m->offset = swap4(CAST(uint32_t, m->offset));
3412 m->in_offset = swap4(CAST(uint32_t, m->in_offset));
3413 m->lineno = swap4(CAST(uint32_t, m->lineno));
3414 if (IS_STRING(m->type)) {
3415 m->str_range = swap4(m->str_range);
3416 m->str_flags = swap4(m->str_flags);
3417 }
3418 else {
3419 m->value.q = swap8(m->value.q);
3420 m->num_mask = swap8(m->num_mask);
3421 }
3422 }
3423
3424 protected size_t
file_pstring_length_size(struct magic_set * ms,const struct magic * m)3425 file_pstring_length_size(struct magic_set *ms, const struct magic *m)
3426 {
3427 switch (m->str_flags & PSTRING_LEN) {
3428 case PSTRING_1_LE:
3429 return 1;
3430 case PSTRING_2_LE:
3431 case PSTRING_2_BE:
3432 return 2;
3433 case PSTRING_4_LE:
3434 case PSTRING_4_BE:
3435 return 4;
3436 default:
3437 file_error(ms, 0, "corrupt magic file "
3438 "(bad pascal string length %d)",
3439 m->str_flags & PSTRING_LEN);
3440 return FILE_BADSIZE;
3441 }
3442 }
3443 protected size_t
file_pstring_get_length(struct magic_set * ms,const struct magic * m,const char * ss)3444 file_pstring_get_length(struct magic_set *ms, const struct magic *m,
3445 const char *ss)
3446 {
3447 size_t len = 0;
3448 const unsigned char *s = RCAST(const unsigned char *, ss);
3449 unsigned int s3, s2, s1, s0;
3450
3451 switch (m->str_flags & PSTRING_LEN) {
3452 case PSTRING_1_LE:
3453 len = *s;
3454 break;
3455 case PSTRING_2_LE:
3456 s0 = s[0];
3457 s1 = s[1];
3458 len = (s1 << 8) | s0;
3459 break;
3460 case PSTRING_2_BE:
3461 s0 = s[0];
3462 s1 = s[1];
3463 len = (s0 << 8) | s1;
3464 break;
3465 case PSTRING_4_LE:
3466 s0 = s[0];
3467 s1 = s[1];
3468 s2 = s[2];
3469 s3 = s[3];
3470 len = (s3 << 24) | (s2 << 16) | (s1 << 8) | s0;
3471 break;
3472 case PSTRING_4_BE:
3473 s0 = s[0];
3474 s1 = s[1];
3475 s2 = s[2];
3476 s3 = s[3];
3477 len = (s0 << 24) | (s1 << 16) | (s2 << 8) | s3;
3478 break;
3479 default:
3480 file_error(ms, 0, "corrupt magic file "
3481 "(bad pascal string length %d)",
3482 m->str_flags & PSTRING_LEN);
3483 return FILE_BADSIZE;
3484 }
3485
3486 if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF) {
3487 size_t l = file_pstring_length_size(ms, m);
3488 if (l == FILE_BADSIZE)
3489 return l;
3490 len -= l;
3491 }
3492
3493 return len;
3494 }
3495
3496 protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3497 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3498 {
3499 uint32_t i, j;
3500 struct mlist *mlist, *ml;
3501
3502 mlist = ms->mlist[1];
3503
3504 for (ml = mlist->next; ml != mlist; ml = ml->next) {
3505 struct magic *ma = ml->magic;
3506 uint32_t nma = ml->nmagic;
3507 for (i = 0; i < nma; i++) {
3508 if (ma[i].type != FILE_NAME)
3509 continue;
3510 if (strcmp(ma[i].value.s, name) == 0) {
3511 v->magic = &ma[i];
3512 for (j = i + 1; j < nma; j++)
3513 if (ma[j].cont_level == 0)
3514 break;
3515 v->nmagic = j - i;
3516 return 0;
3517 }
3518 }
3519 }
3520 return -1;
3521 }
3522