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 1.229 2015/01/01 17:07:34 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 #ifdef HAVE_STDDEF_H
44 #include <stddef.h>
45 #endif
46 #include <string.h>
47 #include <assert.h>
48 #include <ctype.h>
49 #include <fcntl.h>
50 #ifdef QUICK
51 #include <sys/mman.h>
52 #endif
53 #include <dirent.h>
54 #if defined(HAVE_LIMITS_H)
55 #include <limits.h>
56 #endif
57
58 #ifndef SSIZE_MAX
59 #define MAXMAGIC_SIZE ((ssize_t)0x7fffffff)
60 #else
61 #define MAXMAGIC_SIZE SSIZE_MAX
62 #endif
63
64 #define EATAB {while (isascii((unsigned char) *l) && \
65 isspace((unsigned char) *l)) ++l;}
66 #define LOWCASE(l) (isupper((unsigned char) (l)) ? \
67 tolower((unsigned char) (l)) : (l))
68 /*
69 * Work around a bug in headers on Digital Unix.
70 * At least confirmed for: OSF1 V4.0 878
71 */
72 #if defined(__osf__) && defined(__DECC)
73 #ifdef MAP_FAILED
74 #undef MAP_FAILED
75 #endif
76 #endif
77
78 #ifndef MAP_FAILED
79 #define MAP_FAILED (void *) -1
80 #endif
81
82 #ifndef MAP_FILE
83 #define MAP_FILE 0
84 #endif
85
86 #define ALLOC_CHUNK (size_t)10
87 #define ALLOC_INCR (size_t)200
88
89 #define MAP_TYPE_MMAP 0
90 #define MAP_TYPE_MALLOC 1
91 #define MAP_TYPE_USER 2
92
93 struct magic_entry {
94 struct magic *mp;
95 uint32_t cont_count;
96 uint32_t max_count;
97 };
98
99 struct magic_entry_set {
100 struct magic_entry *me;
101 uint32_t count;
102 uint32_t max;
103 };
104
105 struct magic_map {
106 void *p;
107 size_t len;
108 int type;
109 struct magic *magic[MAGIC_SETS];
110 uint32_t nmagic[MAGIC_SETS];
111 };
112
113 int file_formats[FILE_NAMES_SIZE];
114 const size_t file_nformats = FILE_NAMES_SIZE;
115 const char *file_names[FILE_NAMES_SIZE];
116 const size_t file_nnames = FILE_NAMES_SIZE;
117
118 private int getvalue(struct magic_set *ms, struct magic *, const char **, int);
119 private int hextoint(int);
120 private const char *getstr(struct magic_set *, struct magic *, const char *,
121 int);
122 private int parse(struct magic_set *, struct magic_entry *, const char *,
123 size_t, int);
124 private void eatsize(const char **);
125 private int apprentice_1(struct magic_set *, const char *, int);
126 private size_t apprentice_magic_strength(const struct magic *);
127 private int apprentice_sort(const void *, const void *);
128 private void apprentice_list(struct mlist *, int );
129 private struct magic_map *apprentice_load(struct magic_set *,
130 const char *, int);
131 private struct mlist *mlist_alloc(void);
132 private void mlist_free(struct mlist *);
133 private void byteswap(struct magic *, uint32_t);
134 private void bs1(struct magic *);
135 private uint16_t swap2(uint16_t);
136 private uint32_t swap4(uint32_t);
137 private uint64_t swap8(uint64_t);
138 private char *mkdbname(struct magic_set *, const char *, int);
139 private struct magic_map *apprentice_buf(struct magic_set *, struct magic *,
140 size_t);
141 private struct magic_map *apprentice_map(struct magic_set *, const char *);
142 private int check_buffer(struct magic_set *, struct magic_map *, const char *);
143 private void apprentice_unmap(struct magic_map *);
144 private int apprentice_compile(struct magic_set *, struct magic_map *,
145 const char *);
146 private int check_format_type(const char *, int);
147 private int check_format(struct magic_set *, struct magic *);
148 private int get_op(char);
149 private int parse_mime(struct magic_set *, struct magic_entry *, const char *);
150 private int parse_strength(struct magic_set *, struct magic_entry *, const char *);
151 private int parse_apple(struct magic_set *, struct magic_entry *, const char *);
152
153
154 private size_t magicsize = sizeof(struct magic);
155
156 private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
157
158 private struct {
159 const char *name;
160 size_t len;
161 int (*fun)(struct magic_set *, struct magic_entry *, const char *);
162 } bang[] = {
163 #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
164 DECLARE_FIELD(mime),
165 DECLARE_FIELD(apple),
166 DECLARE_FIELD(strength),
167 #undef DECLARE_FIELD
168 { NULL, 0, NULL }
169 };
170
171 #ifdef COMPILE_ONLY
172
173 int main(int, char *[]);
174
175 int
main(int argc,char * argv[])176 main(int argc, char *argv[])
177 {
178 int ret;
179 struct magic_set *ms;
180 char *progname;
181
182 if ((progname = strrchr(argv[0], '/')) != NULL)
183 progname++;
184 else
185 progname = argv[0];
186
187 if (argc != 2) {
188 (void)fprintf(stderr, "Usage: %s file\n", progname);
189 return 1;
190 }
191
192 if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
193 (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
194 return 1;
195 }
196 ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
197 if (ret == 1)
198 (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
199 magic_close(ms);
200 return ret;
201 }
202 #endif /* COMPILE_ONLY */
203
204 struct type_tbl_s {
205 const char name[16];
206 const size_t len;
207 const int type;
208 const int format;
209 };
210
211 /*
212 * XXX - the actual Single UNIX Specification says that "long" means "long",
213 * as in the C data type, but we treat it as meaning "4-byte integer".
214 * Given that the OS X version of file 5.04 did the same, I guess that passes
215 * the actual test; having "long" be dependent on how big a "long" is on
216 * the machine running "file" is silly.
217 */
218 static const struct type_tbl_s type_tbl[] = {
219 # define XX(s) s, (sizeof(s) - 1)
220 # define XX_NULL "", 0
221 { XX("invalid"), FILE_INVALID, FILE_FMT_NONE },
222 { XX("byte"), FILE_BYTE, FILE_FMT_NUM },
223 { XX("short"), FILE_SHORT, FILE_FMT_NUM },
224 { XX("default"), FILE_DEFAULT, FILE_FMT_NONE },
225 { XX("long"), FILE_LONG, FILE_FMT_NUM },
226 { XX("string"), FILE_STRING, FILE_FMT_STR },
227 { XX("date"), FILE_DATE, FILE_FMT_STR },
228 { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM },
229 { XX("belong"), FILE_BELONG, FILE_FMT_NUM },
230 { XX("bedate"), FILE_BEDATE, FILE_FMT_STR },
231 { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM },
232 { XX("lelong"), FILE_LELONG, FILE_FMT_NUM },
233 { XX("ledate"), FILE_LEDATE, FILE_FMT_STR },
234 { XX("pstring"), FILE_PSTRING, FILE_FMT_STR },
235 { XX("ldate"), FILE_LDATE, FILE_FMT_STR },
236 { XX("beldate"), FILE_BELDATE, FILE_FMT_STR },
237 { XX("leldate"), FILE_LELDATE, FILE_FMT_STR },
238 { XX("regex"), FILE_REGEX, FILE_FMT_STR },
239 { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR },
240 { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR },
241 { XX("search"), FILE_SEARCH, FILE_FMT_STR },
242 { XX("medate"), FILE_MEDATE, FILE_FMT_STR },
243 { XX("meldate"), FILE_MELDATE, FILE_FMT_STR },
244 { XX("melong"), FILE_MELONG, FILE_FMT_NUM },
245 { XX("quad"), FILE_QUAD, FILE_FMT_QUAD },
246 { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD },
247 { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD },
248 { XX("qdate"), FILE_QDATE, FILE_FMT_STR },
249 { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR },
250 { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR },
251 { XX("qldate"), FILE_QLDATE, FILE_FMT_STR },
252 { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR },
253 { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR },
254 { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT },
255 { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT },
256 { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT },
257 { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE },
258 { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE },
259 { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE },
260 { XX("leid3"), FILE_LEID3, FILE_FMT_NUM },
261 { XX("beid3"), FILE_BEID3, FILE_FMT_NUM },
262 { XX("indirect"), FILE_INDIRECT, FILE_FMT_NUM },
263 { XX("qwdate"), FILE_QWDATE, FILE_FMT_STR },
264 { XX("leqwdate"), FILE_LEQWDATE, FILE_FMT_STR },
265 { XX("beqwdate"), FILE_BEQWDATE, FILE_FMT_STR },
266 { XX("name"), FILE_NAME, FILE_FMT_NONE },
267 { XX("use"), FILE_USE, FILE_FMT_NONE },
268 { XX("clear"), FILE_CLEAR, FILE_FMT_NONE },
269 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
270 };
271
272 /*
273 * These are not types, and cannot be preceded by "u" to make them
274 * unsigned.
275 */
276 static const struct type_tbl_s special_tbl[] = {
277 { XX("name"), FILE_NAME, FILE_FMT_STR },
278 { XX("use"), FILE_USE, FILE_FMT_STR },
279 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
280 };
281 # undef XX
282 # undef XX_NULL
283
284 private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)285 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
286 {
287 const struct type_tbl_s *p;
288
289 for (p = tbl; p->len; p++) {
290 if (strncmp(l, p->name, p->len) == 0) {
291 if (t)
292 *t = l + p->len;
293 break;
294 }
295 }
296 return p->type;
297 }
298
299 private int
get_standard_integer_type(const char * l,const char ** t)300 get_standard_integer_type(const char *l, const char **t)
301 {
302 int type;
303
304 if (isalpha((unsigned char)l[1])) {
305 switch (l[1]) {
306 case 'C':
307 /* "dC" and "uC" */
308 type = FILE_BYTE;
309 break;
310 case 'S':
311 /* "dS" and "uS" */
312 type = FILE_SHORT;
313 break;
314 case 'I':
315 case 'L':
316 /*
317 * "dI", "dL", "uI", and "uL".
318 *
319 * XXX - the actual Single UNIX Specification says
320 * that "L" means "long", as in the C data type,
321 * but we treat it as meaning "4-byte integer".
322 * Given that the OS X version of file 5.04 did
323 * the same, I guess that passes the actual SUS
324 * validation suite; having "dL" be dependent on
325 * how big a "long" is on the machine running
326 * "file" is silly.
327 */
328 type = FILE_LONG;
329 break;
330 case 'Q':
331 /* "dQ" and "uQ" */
332 type = FILE_QUAD;
333 break;
334 default:
335 /* "d{anything else}", "u{anything else}" */
336 return FILE_INVALID;
337 }
338 l += 2;
339 } else if (isdigit((unsigned char)l[1])) {
340 /*
341 * "d{num}" and "u{num}"; we only support {num} values
342 * of 1, 2, 4, and 8 - the Single UNIX Specification
343 * doesn't say anything about whether arbitrary
344 * values should be supported, but both the Solaris 10
345 * and OS X Mountain Lion versions of file passed the
346 * Single UNIX Specification validation suite, and
347 * neither of them support values bigger than 8 or
348 * non-power-of-2 values.
349 */
350 if (isdigit((unsigned char)l[2])) {
351 /* Multi-digit, so > 9 */
352 return FILE_INVALID;
353 }
354 switch (l[1]) {
355 case '1':
356 type = FILE_BYTE;
357 break;
358 case '2':
359 type = FILE_SHORT;
360 break;
361 case '4':
362 type = FILE_LONG;
363 break;
364 case '8':
365 type = FILE_QUAD;
366 break;
367 default:
368 /* XXX - what about 3, 5, 6, or 7? */
369 return FILE_INVALID;
370 }
371 l += 2;
372 } else {
373 /*
374 * "d" or "u" by itself.
375 */
376 type = FILE_LONG;
377 ++l;
378 }
379 if (t)
380 *t = l;
381 return type;
382 }
383
384 private void
init_file_tables(void)385 init_file_tables(void)
386 {
387 static int done = 0;
388 const struct type_tbl_s *p;
389
390 if (done)
391 return;
392 done++;
393
394 for (p = type_tbl; p->len; p++) {
395 assert(p->type < FILE_NAMES_SIZE);
396 file_names[p->type] = p->name;
397 file_formats[p->type] = p->format;
398 }
399 assert(p - type_tbl == FILE_NAMES_SIZE);
400 }
401
402 private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)403 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
404 {
405 struct mlist *ml;
406
407 mlp->map = idx == 0 ? map : NULL;
408 if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
409 return -1;
410
411 ml->map = NULL;
412 ml->magic = map->magic[idx];
413 ml->nmagic = map->nmagic[idx];
414
415 mlp->prev->next = ml;
416 ml->prev = mlp->prev;
417 ml->next = mlp;
418 mlp->prev = ml;
419 return 0;
420 }
421
422 /*
423 * Handle one file or directory.
424 */
425 private int
apprentice_1(struct magic_set * ms,const char * fn,int action)426 apprentice_1(struct magic_set *ms, const char *fn, int action)
427 {
428 struct magic_map *map;
429 #ifndef COMPILE_ONLY
430 struct mlist *ml;
431 size_t i;
432 #endif
433
434 if (magicsize != FILE_MAGICSIZE) {
435 file_error(ms, 0, "magic element size %lu != %lu",
436 (unsigned long)sizeof(*map->magic[0]),
437 (unsigned long)FILE_MAGICSIZE);
438 return -1;
439 }
440
441 if (action == FILE_COMPILE) {
442 map = apprentice_load(ms, fn, action);
443 if (map == NULL)
444 return -1;
445 return apprentice_compile(ms, map, fn);
446 }
447
448 #ifndef COMPILE_ONLY
449 map = apprentice_map(ms, fn);
450 if (map == NULL) {
451 if (ms->flags & MAGIC_CHECK)
452 file_magwarn(ms, "using regular magic file `%s'", fn);
453 map = apprentice_load(ms, fn, action);
454 if (map == NULL)
455 return -1;
456 }
457
458 for (i = 0; i < MAGIC_SETS; i++) {
459 if (add_mlist(ms->mlist[i], map, i) == -1) {
460 file_oomem(ms, sizeof(*ml));
461 goto fail;
462 }
463 }
464
465 if (action == FILE_LIST) {
466 for (i = 0; i < MAGIC_SETS; i++) {
467 printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
468 i);
469 apprentice_list(ms->mlist[i], BINTEST);
470 printf("Text patterns:\n");
471 apprentice_list(ms->mlist[i], TEXTTEST);
472 }
473 }
474 return 0;
475 fail:
476 for (i = 0; i < MAGIC_SETS; i++) {
477 mlist_free(ms->mlist[i]);
478 ms->mlist[i] = NULL;
479 }
480 return -1;
481 #else
482 return 0;
483 #endif /* COMPILE_ONLY */
484 }
485
486 protected void
file_ms_free(struct magic_set * ms)487 file_ms_free(struct magic_set *ms)
488 {
489 size_t i;
490 if (ms == NULL)
491 return;
492 for (i = 0; i < MAGIC_SETS; i++)
493 mlist_free(ms->mlist[i]);
494 free(ms->o.pbuf);
495 free(ms->o.buf);
496 free(ms->c.li);
497 free(ms);
498 }
499
500 protected struct magic_set *
file_ms_alloc(int flags)501 file_ms_alloc(int flags)
502 {
503 struct magic_set *ms;
504 size_t i, len;
505
506 if ((ms = CAST(struct magic_set *, calloc((size_t)1,
507 sizeof(struct magic_set)))) == NULL)
508 return NULL;
509
510 if (magic_setflags(ms, flags) == -1) {
511 errno = EINVAL;
512 goto free;
513 }
514
515 ms->o.buf = ms->o.pbuf = NULL;
516 len = (ms->c.len = 10) * sizeof(*ms->c.li);
517
518 if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
519 goto free;
520
521 ms->event_flags = 0;
522 ms->error = -1;
523 for (i = 0; i < MAGIC_SETS; i++)
524 ms->mlist[i] = NULL;
525 ms->file = "unknown";
526 ms->line = 0;
527 ms->indir_max = FILE_INDIR_MAX;
528 ms->name_max = FILE_NAME_MAX;
529 ms->elf_shnum_max = FILE_ELF_SHNUM_MAX;
530 ms->elf_phnum_max = FILE_ELF_PHNUM_MAX;
531 ms->elf_notes_max = FILE_ELF_NOTES_MAX;
532 return ms;
533 free:
534 free(ms);
535 return NULL;
536 }
537
538 private void
apprentice_unmap(struct magic_map * map)539 apprentice_unmap(struct magic_map *map)
540 {
541 if (map == NULL)
542 return;
543
544 switch (map->type) {
545 #ifdef QUICK
546 case MAP_TYPE_MMAP:
547 if (map->p)
548 (void)munmap(map->p, map->len);
549 break;
550 #endif
551 case MAP_TYPE_MALLOC:
552 free(map->p);
553 break;
554 case MAP_TYPE_USER:
555 break;
556 default:
557 abort();
558 }
559 free(map);
560 }
561
562 private struct mlist *
mlist_alloc(void)563 mlist_alloc(void)
564 {
565 struct mlist *mlist;
566 if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
567 return NULL;
568 }
569 mlist->next = mlist->prev = mlist;
570 return mlist;
571 }
572
573 private void
mlist_free(struct mlist * mlist)574 mlist_free(struct mlist *mlist)
575 {
576 struct mlist *ml, *next;
577
578 if (mlist == NULL)
579 return;
580
581 ml = mlist->next;
582 for (ml = mlist->next; (next = ml->next) != NULL; ml = next) {
583 if (ml->map)
584 apprentice_unmap(ml->map);
585 free(ml);
586 if (ml == mlist)
587 break;
588 }
589 }
590
591 #ifndef COMPILE_ONLY
592 /* void **bufs: an array of compiled magic files */
593 protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)594 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
595 size_t *sizes, size_t nbufs)
596 {
597 size_t i, j;
598 struct mlist *ml;
599 struct magic_map *map;
600
601 if (nbufs == 0)
602 return -1;
603
604 if (ms->mlist[0] != NULL)
605 file_reset(ms);
606
607 init_file_tables();
608
609 for (i = 0; i < MAGIC_SETS; i++) {
610 mlist_free(ms->mlist[i]);
611 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
612 file_oomem(ms, sizeof(*ms->mlist[i]));
613 goto fail;
614 }
615 }
616
617 for (i = 0; i < nbufs; i++) {
618 map = apprentice_buf(ms, bufs[i], sizes[i]);
619 if (map == NULL)
620 goto fail;
621
622 for (j = 0; j < MAGIC_SETS; j++) {
623 if (add_mlist(ms->mlist[j], map, j) == -1) {
624 file_oomem(ms, sizeof(*ml));
625 goto fail;
626 }
627 }
628 }
629
630 return 0;
631 fail:
632 for (i = 0; i < MAGIC_SETS; i++) {
633 mlist_free(ms->mlist[i]);
634 ms->mlist[i] = NULL;
635 }
636 return -1;
637 }
638 #endif
639
640 /* const char *fn: list of magic files and directories */
641 protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)642 file_apprentice(struct magic_set *ms, const char *fn, int action)
643 {
644 char *p, *mfn;
645 int file_err, errs = -1;
646 size_t i;
647
648 if (ms->mlist[0] != NULL)
649 file_reset(ms);
650
651 if ((fn = magic_getpath(fn, action)) == NULL)
652 return -1;
653
654 init_file_tables();
655
656 if ((mfn = strdup(fn)) == NULL) {
657 file_oomem(ms, strlen(fn));
658 return -1;
659 }
660
661 for (i = 0; i < MAGIC_SETS; i++) {
662 mlist_free(ms->mlist[i]);
663 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
664 file_oomem(ms, sizeof(*ms->mlist[i]));
665 while (i-- > 0) {
666 mlist_free(ms->mlist[i]);
667 ms->mlist[i] = NULL;
668 }
669 free(mfn);
670 return -1;
671 }
672 }
673 fn = mfn;
674
675 while (fn) {
676 p = strchr(fn, PATHSEP);
677 if (p)
678 *p++ = '\0';
679 if (*fn == '\0')
680 break;
681 file_err = apprentice_1(ms, fn, action);
682 errs = MAX(errs, file_err);
683 fn = p;
684 }
685
686 free(mfn);
687
688 if (errs == -1) {
689 for (i = 0; i < MAGIC_SETS; i++) {
690 mlist_free(ms->mlist[i]);
691 ms->mlist[i] = NULL;
692 }
693 file_error(ms, 0, "could not find any valid magic files!");
694 return -1;
695 }
696
697 #if 0
698 /*
699 * Always leave the database loaded
700 */
701 if (action == FILE_LOAD)
702 return 0;
703
704 for (i = 0; i < MAGIC_SETS; i++) {
705 mlist_free(ms->mlist[i]);
706 ms->mlist[i] = NULL;
707 }
708 #endif
709
710 switch (action) {
711 case FILE_LOAD:
712 case FILE_COMPILE:
713 case FILE_CHECK:
714 case FILE_LIST:
715 return 0;
716 default:
717 file_error(ms, 0, "Invalid action %d", action);
718 return -1;
719 }
720 }
721
722 /*
723 * Compute the real length of a magic expression, for the purposes
724 * of determining how "strong" a magic expression is (approximating
725 * how specific its matches are):
726 * - magic characters count 0 unless escaped.
727 * - [] expressions count 1
728 * - {} expressions count 0
729 * - regular characters or escaped magic characters count 1
730 * - 0 length expressions count as one
731 */
732 private size_t
nonmagic(const char * str)733 nonmagic(const char *str)
734 {
735 const char *p;
736 size_t rv = 0;
737
738 for (p = str; *p; p++)
739 switch (*p) {
740 case '\\': /* Escaped anything counts 1 */
741 if (!*++p)
742 p--;
743 rv++;
744 continue;
745 case '?': /* Magic characters count 0 */
746 case '*':
747 case '.':
748 case '+':
749 case '^':
750 case '$':
751 continue;
752 case '[': /* Bracketed expressions count 1 the ']' */
753 while (*p && *p != ']')
754 p++;
755 p--;
756 continue;
757 case '{': /* Braced expressions count 0 */
758 while (*p && *p != '}')
759 p++;
760 if (!*p)
761 p--;
762 continue;
763 default: /* Anything else counts 1 */
764 rv++;
765 continue;
766 }
767
768 return rv == 0 ? 1 : rv; /* Return at least 1 */
769 }
770
771 /*
772 * Get weight of this magic entry, for sorting purposes.
773 */
774 private size_t
apprentice_magic_strength(const struct magic * m)775 apprentice_magic_strength(const struct magic *m)
776 {
777 #define MULT 10
778 size_t v, val = 2 * MULT; /* baseline strength */
779
780 switch (m->type) {
781 case FILE_DEFAULT: /* make sure this sorts last */
782 if (m->factor_op != FILE_FACTOR_OP_NONE)
783 abort();
784 return 0;
785
786 case FILE_BYTE:
787 val += 1 * MULT;
788 break;
789
790 case FILE_SHORT:
791 case FILE_LESHORT:
792 case FILE_BESHORT:
793 val += 2 * MULT;
794 break;
795
796 case FILE_LONG:
797 case FILE_LELONG:
798 case FILE_BELONG:
799 case FILE_MELONG:
800 val += 4 * MULT;
801 break;
802
803 case FILE_PSTRING:
804 case FILE_STRING:
805 val += m->vallen * MULT;
806 break;
807
808 case FILE_BESTRING16:
809 case FILE_LESTRING16:
810 val += m->vallen * MULT / 2;
811 break;
812
813 case FILE_SEARCH:
814 val += m->vallen * MAX(MULT / m->vallen, 1);
815 break;
816
817 case FILE_REGEX:
818 v = nonmagic(m->value.s);
819 val += v * MAX(MULT / v, 1);
820 break;
821
822 case FILE_DATE:
823 case FILE_LEDATE:
824 case FILE_BEDATE:
825 case FILE_MEDATE:
826 case FILE_LDATE:
827 case FILE_LELDATE:
828 case FILE_BELDATE:
829 case FILE_MELDATE:
830 case FILE_FLOAT:
831 case FILE_BEFLOAT:
832 case FILE_LEFLOAT:
833 val += 4 * MULT;
834 break;
835
836 case FILE_QUAD:
837 case FILE_BEQUAD:
838 case FILE_LEQUAD:
839 case FILE_QDATE:
840 case FILE_LEQDATE:
841 case FILE_BEQDATE:
842 case FILE_QLDATE:
843 case FILE_LEQLDATE:
844 case FILE_BEQLDATE:
845 case FILE_QWDATE:
846 case FILE_LEQWDATE:
847 case FILE_BEQWDATE:
848 case FILE_DOUBLE:
849 case FILE_BEDOUBLE:
850 case FILE_LEDOUBLE:
851 val += 8 * MULT;
852 break;
853
854 case FILE_INDIRECT:
855 case FILE_NAME:
856 case FILE_USE:
857 break;
858
859 default:
860 (void)fprintf(stderr, "Bad type %d\n", m->type);
861 abort();
862 }
863
864 switch (m->reln) {
865 case 'x': /* matches anything penalize */
866 case '!': /* matches almost anything penalize */
867 val = 0;
868 break;
869
870 case '=': /* Exact match, prefer */
871 val += MULT;
872 break;
873
874 case '>':
875 case '<': /* comparison match reduce strength */
876 val -= 2 * MULT;
877 break;
878
879 case '^':
880 case '&': /* masking bits, we could count them too */
881 val -= MULT;
882 break;
883
884 default:
885 (void)fprintf(stderr, "Bad relation %c\n", m->reln);
886 abort();
887 }
888
889 if (val == 0) /* ensure we only return 0 for FILE_DEFAULT */
890 val = 1;
891
892 switch (m->factor_op) {
893 case FILE_FACTOR_OP_NONE:
894 break;
895 case FILE_FACTOR_OP_PLUS:
896 val += m->factor;
897 break;
898 case FILE_FACTOR_OP_MINUS:
899 val -= m->factor;
900 break;
901 case FILE_FACTOR_OP_TIMES:
902 val *= m->factor;
903 break;
904 case FILE_FACTOR_OP_DIV:
905 val /= m->factor;
906 break;
907 default:
908 abort();
909 }
910
911 /*
912 * Magic entries with no description get a bonus because they depend
913 * on subsequent magic entries to print something.
914 */
915 if (m->desc[0] == '\0')
916 val++;
917 return val;
918 }
919
920 /*
921 * Sort callback for sorting entries by "strength" (basically length)
922 */
923 private int
apprentice_sort(const void * a,const void * b)924 apprentice_sort(const void *a, const void *b)
925 {
926 const struct magic_entry *ma = CAST(const struct magic_entry *, a);
927 const struct magic_entry *mb = CAST(const struct magic_entry *, b);
928 size_t sa = apprentice_magic_strength(ma->mp);
929 size_t sb = apprentice_magic_strength(mb->mp);
930 if (sa == sb)
931 return 0;
932 else if (sa > sb)
933 return -1;
934 else
935 return 1;
936 }
937
938 /*
939 * Shows sorted patterns list in the order which is used for the matching
940 */
941 private void
apprentice_list(struct mlist * mlist,int mode)942 apprentice_list(struct mlist *mlist, int mode)
943 {
944 uint32_t magindex = 0;
945 struct mlist *ml;
946 for (ml = mlist->next; ml != mlist; ml = ml->next) {
947 for (magindex = 0; magindex < ml->nmagic; magindex++) {
948 struct magic *m = &ml->magic[magindex];
949 if ((m->flag & mode) != mode) {
950 /* Skip sub-tests */
951 while (magindex + 1 < ml->nmagic &&
952 ml->magic[magindex + 1].cont_level != 0)
953 ++magindex;
954 continue; /* Skip to next top-level test*/
955 }
956
957 /*
958 * Try to iterate over the tree until we find item with
959 * description/mimetype.
960 */
961 while (magindex + 1 < ml->nmagic &&
962 ml->magic[magindex + 1].cont_level != 0 &&
963 *ml->magic[magindex].desc == '\0' &&
964 *ml->magic[magindex].mimetype == '\0')
965 magindex++;
966
967 printf("Strength = %3" SIZE_T_FORMAT "u : %s [%s]\n",
968 apprentice_magic_strength(m),
969 ml->magic[magindex].desc,
970 ml->magic[magindex].mimetype);
971 }
972 }
973 }
974
975 private void
set_test_type(struct magic * mstart,struct magic * m)976 set_test_type(struct magic *mstart, struct magic *m)
977 {
978 switch (m->type) {
979 case FILE_BYTE:
980 case FILE_SHORT:
981 case FILE_LONG:
982 case FILE_DATE:
983 case FILE_BESHORT:
984 case FILE_BELONG:
985 case FILE_BEDATE:
986 case FILE_LESHORT:
987 case FILE_LELONG:
988 case FILE_LEDATE:
989 case FILE_LDATE:
990 case FILE_BELDATE:
991 case FILE_LELDATE:
992 case FILE_MEDATE:
993 case FILE_MELDATE:
994 case FILE_MELONG:
995 case FILE_QUAD:
996 case FILE_LEQUAD:
997 case FILE_BEQUAD:
998 case FILE_QDATE:
999 case FILE_LEQDATE:
1000 case FILE_BEQDATE:
1001 case FILE_QLDATE:
1002 case FILE_LEQLDATE:
1003 case FILE_BEQLDATE:
1004 case FILE_QWDATE:
1005 case FILE_LEQWDATE:
1006 case FILE_BEQWDATE:
1007 case FILE_FLOAT:
1008 case FILE_BEFLOAT:
1009 case FILE_LEFLOAT:
1010 case FILE_DOUBLE:
1011 case FILE_BEDOUBLE:
1012 case FILE_LEDOUBLE:
1013 mstart->flag |= BINTEST;
1014 break;
1015 case FILE_STRING:
1016 case FILE_PSTRING:
1017 case FILE_BESTRING16:
1018 case FILE_LESTRING16:
1019 /* Allow text overrides */
1020 if (mstart->str_flags & STRING_TEXTTEST)
1021 mstart->flag |= TEXTTEST;
1022 else
1023 mstart->flag |= BINTEST;
1024 break;
1025 case FILE_REGEX:
1026 case FILE_SEARCH:
1027 /* Check for override */
1028 if (mstart->str_flags & STRING_BINTEST)
1029 mstart->flag |= BINTEST;
1030 if (mstart->str_flags & STRING_TEXTTEST)
1031 mstart->flag |= TEXTTEST;
1032
1033 if (mstart->flag & (TEXTTEST|BINTEST))
1034 break;
1035
1036 /* binary test if pattern is not text */
1037 if (file_looks_utf8(m->value.us, (size_t)m->vallen, NULL,
1038 NULL) <= 0)
1039 mstart->flag |= BINTEST;
1040 else
1041 mstart->flag |= TEXTTEST;
1042 break;
1043 case FILE_DEFAULT:
1044 /* can't deduce anything; we shouldn't see this at the
1045 top level anyway */
1046 break;
1047 case FILE_INVALID:
1048 default:
1049 /* invalid search type, but no need to complain here */
1050 break;
1051 }
1052 }
1053
1054 private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1055 addentry(struct magic_set *ms, struct magic_entry *me,
1056 struct magic_entry_set *mset)
1057 {
1058 size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1059 if (mset[i].count == mset[i].max) {
1060 struct magic_entry *mp;
1061
1062 mset[i].max += ALLOC_INCR;
1063 if ((mp = CAST(struct magic_entry *,
1064 realloc(mset[i].me, sizeof(*mp) * mset[i].max))) ==
1065 NULL) {
1066 file_oomem(ms, sizeof(*mp) * mset[i].max);
1067 return -1;
1068 }
1069 (void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1070 ALLOC_INCR);
1071 mset[i].me = mp;
1072 }
1073 mset[i].me[mset[i].count++] = *me;
1074 memset(me, 0, sizeof(*me));
1075 return 0;
1076 }
1077
1078 /*
1079 * Load and parse one file.
1080 */
1081 private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1082 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1083 struct magic_entry_set *mset)
1084 {
1085 size_t lineno = 0, llen = 0;
1086 char *line = NULL;
1087 ssize_t len;
1088 struct magic_entry me;
1089
1090 FILE *f = fopen(ms->file = fn, "r");
1091 if (f == NULL) {
1092 if (errno != ENOENT)
1093 file_error(ms, errno, "cannot read magic file `%s'",
1094 fn);
1095 (*errs)++;
1096 return;
1097 }
1098
1099 memset(&me, 0, sizeof(me));
1100 /* read and parse this file */
1101 for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1102 ms->line++) {
1103 if (len == 0) /* null line, garbage, etc */
1104 continue;
1105 if (line[len - 1] == '\n') {
1106 lineno++;
1107 line[len - 1] = '\0'; /* delete newline */
1108 }
1109 switch (line[0]) {
1110 case '\0': /* empty, do not parse */
1111 case '#': /* comment, do not parse */
1112 continue;
1113 case '!':
1114 if (line[1] == ':') {
1115 size_t i;
1116
1117 for (i = 0; bang[i].name != NULL; i++) {
1118 if ((size_t)(len - 2) > bang[i].len &&
1119 memcmp(bang[i].name, line + 2,
1120 bang[i].len) == 0)
1121 break;
1122 }
1123 if (bang[i].name == NULL) {
1124 file_error(ms, 0,
1125 "Unknown !: entry `%s'", line);
1126 (*errs)++;
1127 continue;
1128 }
1129 if (me.mp == NULL) {
1130 file_error(ms, 0,
1131 "No current entry for :!%s type",
1132 bang[i].name);
1133 (*errs)++;
1134 continue;
1135 }
1136 if ((*bang[i].fun)(ms, &me,
1137 line + bang[i].len + 2) != 0) {
1138 (*errs)++;
1139 continue;
1140 }
1141 continue;
1142 }
1143 /*FALLTHROUGH*/
1144 default:
1145 again:
1146 switch (parse(ms, &me, line, lineno, action)) {
1147 case 0:
1148 continue;
1149 case 1:
1150 (void)addentry(ms, &me, mset);
1151 goto again;
1152 default:
1153 (*errs)++;
1154 break;
1155 }
1156 }
1157 }
1158 if (me.mp)
1159 (void)addentry(ms, &me, mset);
1160 free(line);
1161 (void)fclose(f);
1162 }
1163
1164 /*
1165 * parse a file or directory of files
1166 * const char *fn: name of magic file or directory
1167 */
1168 private int
cmpstrp(const void * p1,const void * p2)1169 cmpstrp(const void *p1, const void *p2)
1170 {
1171 return strcmp(*(char *const *)p1, *(char *const *)p2);
1172 }
1173
1174
1175 private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1176 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1177 uint32_t starttest)
1178 {
1179 static const char text[] = "text";
1180 static const char binary[] = "binary";
1181 static const size_t len = sizeof(text);
1182
1183 uint32_t i = starttest;
1184
1185 do {
1186 set_test_type(me[starttest].mp, me[i].mp);
1187 if ((ms->flags & MAGIC_DEBUG) == 0)
1188 continue;
1189 (void)fprintf(stderr, "%s%s%s: %s\n",
1190 me[i].mp->mimetype,
1191 me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1192 me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1193 me[i].mp->flag & BINTEST ? binary : text);
1194 if (me[i].mp->flag & BINTEST) {
1195 char *p = strstr(me[i].mp->desc, text);
1196 if (p && (p == me[i].mp->desc ||
1197 isspace((unsigned char)p[-1])) &&
1198 (p + len - me[i].mp->desc == MAXstring
1199 || (p[len] == '\0' ||
1200 isspace((unsigned char)p[len]))))
1201 (void)fprintf(stderr, "*** Possible "
1202 "binary test for text type\n");
1203 }
1204 } while (++i < nme && me[i].mp->cont_level != 0);
1205 return i;
1206 }
1207
1208 private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1209 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1210 {
1211 uint32_t i;
1212 for (i = 0; i < nme; i++) {
1213 if (me[i].mp->cont_level == 0 &&
1214 me[i].mp->type == FILE_DEFAULT) {
1215 while (++i < nme)
1216 if (me[i].mp->cont_level == 0)
1217 break;
1218 if (i != nme) {
1219 /* XXX - Ugh! */
1220 ms->line = me[i].mp->lineno;
1221 file_magwarn(ms,
1222 "level 0 \"default\" did not sort last");
1223 }
1224 return;
1225 }
1226 }
1227 }
1228
1229 private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1230 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1231 struct magic **ma, uint32_t *nma)
1232 {
1233 uint32_t i, mentrycount = 0;
1234 size_t slen;
1235
1236 for (i = 0; i < nme; i++)
1237 mentrycount += me[i].cont_count;
1238
1239 slen = sizeof(**ma) * mentrycount;
1240 if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1241 file_oomem(ms, slen);
1242 return -1;
1243 }
1244
1245 mentrycount = 0;
1246 for (i = 0; i < nme; i++) {
1247 (void)memcpy(*ma + mentrycount, me[i].mp,
1248 me[i].cont_count * sizeof(**ma));
1249 mentrycount += me[i].cont_count;
1250 }
1251 *nma = mentrycount;
1252 return 0;
1253 }
1254
1255 private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1256 magic_entry_free(struct magic_entry *me, uint32_t nme)
1257 {
1258 uint32_t i;
1259 if (me == NULL)
1260 return;
1261 for (i = 0; i < nme; i++)
1262 free(me[i].mp);
1263 free(me);
1264 }
1265
1266 private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1267 apprentice_load(struct magic_set *ms, const char *fn, int action)
1268 {
1269 int errs = 0;
1270 uint32_t i, j;
1271 size_t files = 0, maxfiles = 0;
1272 char **filearr = NULL, *mfn;
1273 struct stat st;
1274 struct magic_map *map;
1275 struct magic_entry_set mset[MAGIC_SETS];
1276 DIR *dir;
1277 struct dirent *d;
1278
1279 memset(mset, 0, sizeof(mset));
1280 ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */
1281
1282
1283 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1284 {
1285 file_oomem(ms, sizeof(*map));
1286 return NULL;
1287 }
1288
1289 /* print silly verbose header for USG compat. */
1290 if (action == FILE_CHECK)
1291 (void)fprintf(stderr, "%s\n", usg_hdr);
1292
1293 /* load directory or file */
1294 if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1295 dir = opendir(fn);
1296 if (!dir) {
1297 errs++;
1298 goto out;
1299 }
1300 while ((d = readdir(dir)) != NULL) {
1301 if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1302 file_oomem(ms,
1303 strlen(fn) + strlen(d->d_name) + 2);
1304 errs++;
1305 closedir(dir);
1306 goto out;
1307 }
1308 if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1309 free(mfn);
1310 continue;
1311 }
1312 if (files >= maxfiles) {
1313 size_t mlen;
1314 maxfiles = (maxfiles + 1) * 2;
1315 mlen = maxfiles * sizeof(*filearr);
1316 if ((filearr = CAST(char **,
1317 realloc(filearr, mlen))) == NULL) {
1318 file_oomem(ms, mlen);
1319 free(mfn);
1320 closedir(dir);
1321 errs++;
1322 goto out;
1323 }
1324 }
1325 filearr[files++] = mfn;
1326 }
1327 closedir(dir);
1328 qsort(filearr, files, sizeof(*filearr), cmpstrp);
1329 for (i = 0; i < files; i++) {
1330 load_1(ms, action, filearr[i], &errs, mset);
1331 free(filearr[i]);
1332 }
1333 free(filearr);
1334 } else
1335 load_1(ms, action, fn, &errs, mset);
1336 if (errs)
1337 goto out;
1338
1339 for (j = 0; j < MAGIC_SETS; j++) {
1340 /* Set types of tests */
1341 for (i = 0; i < mset[j].count; ) {
1342 if (mset[j].me[i].mp->cont_level != 0) {
1343 i++;
1344 continue;
1345 }
1346 i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1347 }
1348 qsort(mset[j].me, mset[j].count, sizeof(*mset[j].me),
1349 apprentice_sort);
1350
1351 /*
1352 * Make sure that any level 0 "default" line is last
1353 * (if one exists).
1354 */
1355 set_last_default(ms, mset[j].me, mset[j].count);
1356
1357 /* coalesce per file arrays into a single one */
1358 if (coalesce_entries(ms, mset[j].me, mset[j].count,
1359 &map->magic[j], &map->nmagic[j]) == -1) {
1360 errs++;
1361 goto out;
1362 }
1363 }
1364
1365 out:
1366 for (j = 0; j < MAGIC_SETS; j++)
1367 magic_entry_free(mset[j].me, mset[j].count);
1368
1369 if (errs) {
1370 apprentice_unmap(map);
1371 return NULL;
1372 }
1373 return map;
1374 }
1375
1376 /*
1377 * extend the sign bit if the comparison is to be signed
1378 */
1379 protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1380 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1381 {
1382 if (!(m->flag & UNSIGNED)) {
1383 switch(m->type) {
1384 /*
1385 * Do not remove the casts below. They are
1386 * vital. When later compared with the data,
1387 * the sign extension must have happened.
1388 */
1389 case FILE_BYTE:
1390 v = (signed char) v;
1391 break;
1392 case FILE_SHORT:
1393 case FILE_BESHORT:
1394 case FILE_LESHORT:
1395 v = (short) v;
1396 break;
1397 case FILE_DATE:
1398 case FILE_BEDATE:
1399 case FILE_LEDATE:
1400 case FILE_MEDATE:
1401 case FILE_LDATE:
1402 case FILE_BELDATE:
1403 case FILE_LELDATE:
1404 case FILE_MELDATE:
1405 case FILE_LONG:
1406 case FILE_BELONG:
1407 case FILE_LELONG:
1408 case FILE_MELONG:
1409 case FILE_FLOAT:
1410 case FILE_BEFLOAT:
1411 case FILE_LEFLOAT:
1412 v = (int32_t) v;
1413 break;
1414 case FILE_QUAD:
1415 case FILE_BEQUAD:
1416 case FILE_LEQUAD:
1417 case FILE_QDATE:
1418 case FILE_QLDATE:
1419 case FILE_QWDATE:
1420 case FILE_BEQDATE:
1421 case FILE_BEQLDATE:
1422 case FILE_BEQWDATE:
1423 case FILE_LEQDATE:
1424 case FILE_LEQLDATE:
1425 case FILE_LEQWDATE:
1426 case FILE_DOUBLE:
1427 case FILE_BEDOUBLE:
1428 case FILE_LEDOUBLE:
1429 v = (int64_t) v;
1430 break;
1431 case FILE_STRING:
1432 case FILE_PSTRING:
1433 case FILE_BESTRING16:
1434 case FILE_LESTRING16:
1435 case FILE_REGEX:
1436 case FILE_SEARCH:
1437 case FILE_DEFAULT:
1438 case FILE_INDIRECT:
1439 case FILE_NAME:
1440 case FILE_USE:
1441 case FILE_CLEAR:
1442 break;
1443 default:
1444 if (ms->flags & MAGIC_CHECK)
1445 file_magwarn(ms, "cannot happen: m->type=%d\n",
1446 m->type);
1447 return ~0U;
1448 }
1449 }
1450 return v;
1451 }
1452
1453 private int
string_modifier_check(struct magic_set * ms,struct magic * m)1454 string_modifier_check(struct magic_set *ms, struct magic *m)
1455 {
1456 if ((ms->flags & MAGIC_CHECK) == 0)
1457 return 0;
1458
1459 if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1460 (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1461 file_magwarn(ms,
1462 "'/BHhLl' modifiers are only allowed for pascal strings\n");
1463 return -1;
1464 }
1465 switch (m->type) {
1466 case FILE_BESTRING16:
1467 case FILE_LESTRING16:
1468 if (m->str_flags != 0) {
1469 file_magwarn(ms,
1470 "no modifiers allowed for 16-bit strings\n");
1471 return -1;
1472 }
1473 break;
1474 case FILE_STRING:
1475 case FILE_PSTRING:
1476 if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1477 file_magwarn(ms,
1478 "'/%c' only allowed on regex and search\n",
1479 CHAR_REGEX_OFFSET_START);
1480 return -1;
1481 }
1482 break;
1483 case FILE_SEARCH:
1484 if (m->str_range == 0) {
1485 file_magwarn(ms,
1486 "missing range; defaulting to %d\n",
1487 STRING_DEFAULT_RANGE);
1488 m->str_range = STRING_DEFAULT_RANGE;
1489 return -1;
1490 }
1491 break;
1492 case FILE_REGEX:
1493 if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1494 file_magwarn(ms, "'/%c' not allowed on regex\n",
1495 CHAR_COMPACT_WHITESPACE);
1496 return -1;
1497 }
1498 if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1499 file_magwarn(ms, "'/%c' not allowed on regex\n",
1500 CHAR_COMPACT_OPTIONAL_WHITESPACE);
1501 return -1;
1502 }
1503 break;
1504 default:
1505 file_magwarn(ms, "coding error: m->type=%d\n",
1506 m->type);
1507 return -1;
1508 }
1509 return 0;
1510 }
1511
1512 private int
get_op(char c)1513 get_op(char c)
1514 {
1515 switch (c) {
1516 case '&':
1517 return FILE_OPAND;
1518 case '|':
1519 return FILE_OPOR;
1520 case '^':
1521 return FILE_OPXOR;
1522 case '+':
1523 return FILE_OPADD;
1524 case '-':
1525 return FILE_OPMINUS;
1526 case '*':
1527 return FILE_OPMULTIPLY;
1528 case '/':
1529 return FILE_OPDIVIDE;
1530 case '%':
1531 return FILE_OPMODULO;
1532 default:
1533 return -1;
1534 }
1535 }
1536
1537 #ifdef ENABLE_CONDITIONALS
1538 private int
get_cond(const char * l,const char ** t)1539 get_cond(const char *l, const char **t)
1540 {
1541 static const struct cond_tbl_s {
1542 char name[8];
1543 size_t len;
1544 int cond;
1545 } cond_tbl[] = {
1546 { "if", 2, COND_IF },
1547 { "elif", 4, COND_ELIF },
1548 { "else", 4, COND_ELSE },
1549 { "", 0, COND_NONE },
1550 };
1551 const struct cond_tbl_s *p;
1552
1553 for (p = cond_tbl; p->len; p++) {
1554 if (strncmp(l, p->name, p->len) == 0 &&
1555 isspace((unsigned char)l[p->len])) {
1556 if (t)
1557 *t = l + p->len;
1558 break;
1559 }
1560 }
1561 return p->cond;
1562 }
1563
1564 private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1565 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1566 {
1567 int last_cond;
1568 last_cond = ms->c.li[cont_level].last_cond;
1569
1570 switch (cond) {
1571 case COND_IF:
1572 if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1573 if (ms->flags & MAGIC_CHECK)
1574 file_magwarn(ms, "syntax error: `if'");
1575 return -1;
1576 }
1577 last_cond = COND_IF;
1578 break;
1579
1580 case COND_ELIF:
1581 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1582 if (ms->flags & MAGIC_CHECK)
1583 file_magwarn(ms, "syntax error: `elif'");
1584 return -1;
1585 }
1586 last_cond = COND_ELIF;
1587 break;
1588
1589 case COND_ELSE:
1590 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1591 if (ms->flags & MAGIC_CHECK)
1592 file_magwarn(ms, "syntax error: `else'");
1593 return -1;
1594 }
1595 last_cond = COND_NONE;
1596 break;
1597
1598 case COND_NONE:
1599 last_cond = COND_NONE;
1600 break;
1601 }
1602
1603 ms->c.li[cont_level].last_cond = last_cond;
1604 return 0;
1605 }
1606 #endif /* ENABLE_CONDITIONALS */
1607
1608 private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1609 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1610 {
1611 const char *l = *lp;
1612
1613 while (!isspace((unsigned char)*++l))
1614 switch (*l) {
1615 case CHAR_INDIRECT_RELATIVE:
1616 m->str_flags |= INDIRECT_RELATIVE;
1617 break;
1618 default:
1619 if (ms->flags & MAGIC_CHECK)
1620 file_magwarn(ms, "indirect modifier `%c' "
1621 "invalid", *l);
1622 *lp = l;
1623 return -1;
1624 }
1625 *lp = l;
1626 return 0;
1627 }
1628
1629 private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1630 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1631 int op)
1632 {
1633 const char *l = *lp;
1634 char *t;
1635 uint64_t val;
1636
1637 ++l;
1638 m->mask_op |= op;
1639 val = (uint64_t)strtoull(l, &t, 0);
1640 l = t;
1641 m->num_mask = file_signextend(ms, m, val);
1642 eatsize(&l);
1643 *lp = l;
1644 }
1645
1646 private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1647 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1648 {
1649 const char *l = *lp;
1650 char *t;
1651 int have_range = 0;
1652
1653 while (!isspace((unsigned char)*++l)) {
1654 switch (*l) {
1655 case '0': case '1': case '2':
1656 case '3': case '4': case '5':
1657 case '6': case '7': case '8':
1658 case '9':
1659 if (have_range && (ms->flags & MAGIC_CHECK))
1660 file_magwarn(ms, "multiple ranges");
1661 have_range = 1;
1662 m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1663 if (m->str_range == 0)
1664 file_magwarn(ms, "zero range");
1665 l = t - 1;
1666 break;
1667 case CHAR_COMPACT_WHITESPACE:
1668 m->str_flags |= STRING_COMPACT_WHITESPACE;
1669 break;
1670 case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1671 m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1672 break;
1673 case CHAR_IGNORE_LOWERCASE:
1674 m->str_flags |= STRING_IGNORE_LOWERCASE;
1675 break;
1676 case CHAR_IGNORE_UPPERCASE:
1677 m->str_flags |= STRING_IGNORE_UPPERCASE;
1678 break;
1679 case CHAR_REGEX_OFFSET_START:
1680 m->str_flags |= REGEX_OFFSET_START;
1681 break;
1682 case CHAR_BINTEST:
1683 m->str_flags |= STRING_BINTEST;
1684 break;
1685 case CHAR_TEXTTEST:
1686 m->str_flags |= STRING_TEXTTEST;
1687 break;
1688 case CHAR_TRIM:
1689 m->str_flags |= STRING_TRIM;
1690 break;
1691 case CHAR_PSTRING_1_LE:
1692 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1693 if (m->type != FILE_PSTRING)
1694 goto bad;
1695 SET_LENGTH(PSTRING_1_LE);
1696 break;
1697 case CHAR_PSTRING_2_BE:
1698 if (m->type != FILE_PSTRING)
1699 goto bad;
1700 SET_LENGTH(PSTRING_2_BE);
1701 break;
1702 case CHAR_PSTRING_2_LE:
1703 if (m->type != FILE_PSTRING)
1704 goto bad;
1705 SET_LENGTH(PSTRING_2_LE);
1706 break;
1707 case CHAR_PSTRING_4_BE:
1708 if (m->type != FILE_PSTRING)
1709 goto bad;
1710 SET_LENGTH(PSTRING_4_BE);
1711 break;
1712 case CHAR_PSTRING_4_LE:
1713 switch (m->type) {
1714 case FILE_PSTRING:
1715 case FILE_REGEX:
1716 break;
1717 default:
1718 goto bad;
1719 }
1720 SET_LENGTH(PSTRING_4_LE);
1721 break;
1722 case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
1723 if (m->type != FILE_PSTRING)
1724 goto bad;
1725 m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
1726 break;
1727 default:
1728 bad:
1729 if (ms->flags & MAGIC_CHECK)
1730 file_magwarn(ms, "string modifier `%c' "
1731 "invalid", *l);
1732 goto out;
1733 }
1734 /* allow multiple '/' for readability */
1735 if (l[1] == '/' && !isspace((unsigned char)l[2]))
1736 l++;
1737 }
1738 if (string_modifier_check(ms, m) == -1)
1739 goto out;
1740 *lp = l;
1741 return 0;
1742 out:
1743 *lp = l;
1744 return -1;
1745 }
1746
1747 /*
1748 * parse one line from magic file, put into magic[index++] if valid
1749 */
1750 private int
parse(struct magic_set * ms,struct magic_entry * me,const char * line,size_t lineno,int action)1751 parse(struct magic_set *ms, struct magic_entry *me, const char *line,
1752 size_t lineno, int action)
1753 {
1754 #ifdef ENABLE_CONDITIONALS
1755 static uint32_t last_cont_level = 0;
1756 #endif
1757 size_t i;
1758 struct magic *m;
1759 const char *l = line;
1760 char *t;
1761 int op;
1762 uint32_t cont_level;
1763 int32_t diff;
1764
1765 cont_level = 0;
1766
1767 /*
1768 * Parse the offset.
1769 */
1770 while (*l == '>') {
1771 ++l; /* step over */
1772 cont_level++;
1773 }
1774 #ifdef ENABLE_CONDITIONALS
1775 if (cont_level == 0 || cont_level > last_cont_level)
1776 if (file_check_mem(ms, cont_level) == -1)
1777 return -1;
1778 last_cont_level = cont_level;
1779 #endif
1780 if (cont_level != 0) {
1781 if (me->mp == NULL) {
1782 file_magerror(ms, "No current entry for continuation");
1783 return -1;
1784 }
1785 if (me->cont_count == 0) {
1786 file_magerror(ms, "Continuations present with 0 count");
1787 return -1;
1788 }
1789 m = &me->mp[me->cont_count - 1];
1790 diff = (int32_t)cont_level - (int32_t)m->cont_level;
1791 if (diff > 1)
1792 file_magwarn(ms, "New continuation level %u is more "
1793 "than one larger than current level %u", cont_level,
1794 m->cont_level);
1795 if (me->cont_count == me->max_count) {
1796 struct magic *nm;
1797 size_t cnt = me->max_count + ALLOC_CHUNK;
1798 if ((nm = CAST(struct magic *, realloc(me->mp,
1799 sizeof(*nm) * cnt))) == NULL) {
1800 file_oomem(ms, sizeof(*nm) * cnt);
1801 return -1;
1802 }
1803 me->mp = m = nm;
1804 me->max_count = CAST(uint32_t, cnt);
1805 }
1806 m = &me->mp[me->cont_count++];
1807 (void)memset(m, 0, sizeof(*m));
1808 m->cont_level = cont_level;
1809 } else {
1810 static const size_t len = sizeof(*m) * ALLOC_CHUNK;
1811 if (me->mp != NULL)
1812 return 1;
1813 if ((m = CAST(struct magic *, malloc(len))) == NULL) {
1814 file_oomem(ms, len);
1815 return -1;
1816 }
1817 me->mp = m;
1818 me->max_count = ALLOC_CHUNK;
1819 (void)memset(m, 0, sizeof(*m));
1820 m->factor_op = FILE_FACTOR_OP_NONE;
1821 m->cont_level = 0;
1822 me->cont_count = 1;
1823 }
1824 m->lineno = CAST(uint32_t, lineno);
1825
1826 if (*l == '&') { /* m->cont_level == 0 checked below. */
1827 ++l; /* step over */
1828 m->flag |= OFFADD;
1829 }
1830 if (*l == '(') {
1831 ++l; /* step over */
1832 m->flag |= INDIR;
1833 if (m->flag & OFFADD)
1834 m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
1835
1836 if (*l == '&') { /* m->cont_level == 0 checked below */
1837 ++l; /* step over */
1838 m->flag |= OFFADD;
1839 }
1840 }
1841 /* Indirect offsets are not valid at level 0. */
1842 if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD)))
1843 if (ms->flags & MAGIC_CHECK)
1844 file_magwarn(ms, "relative offset at level 0");
1845
1846 /* get offset, then skip over it */
1847 m->offset = (uint32_t)strtoul(l, &t, 0);
1848 if (l == t)
1849 if (ms->flags & MAGIC_CHECK)
1850 file_magwarn(ms, "offset `%s' invalid", l);
1851 l = t;
1852
1853 if (m->flag & INDIR) {
1854 m->in_type = FILE_LONG;
1855 m->in_offset = 0;
1856 /*
1857 * read [.lbs][+-]nnnnn)
1858 */
1859 if (*l == '.') {
1860 l++;
1861 switch (*l) {
1862 case 'l':
1863 m->in_type = FILE_LELONG;
1864 break;
1865 case 'L':
1866 m->in_type = FILE_BELONG;
1867 break;
1868 case 'm':
1869 m->in_type = FILE_MELONG;
1870 break;
1871 case 'h':
1872 case 's':
1873 m->in_type = FILE_LESHORT;
1874 break;
1875 case 'H':
1876 case 'S':
1877 m->in_type = FILE_BESHORT;
1878 break;
1879 case 'c':
1880 case 'b':
1881 case 'C':
1882 case 'B':
1883 m->in_type = FILE_BYTE;
1884 break;
1885 case 'e':
1886 case 'f':
1887 case 'g':
1888 m->in_type = FILE_LEDOUBLE;
1889 break;
1890 case 'E':
1891 case 'F':
1892 case 'G':
1893 m->in_type = FILE_BEDOUBLE;
1894 break;
1895 case 'i':
1896 m->in_type = FILE_LEID3;
1897 break;
1898 case 'I':
1899 m->in_type = FILE_BEID3;
1900 break;
1901 default:
1902 if (ms->flags & MAGIC_CHECK)
1903 file_magwarn(ms,
1904 "indirect offset type `%c' invalid",
1905 *l);
1906 break;
1907 }
1908 l++;
1909 }
1910
1911 m->in_op = 0;
1912 if (*l == '~') {
1913 m->in_op |= FILE_OPINVERSE;
1914 l++;
1915 }
1916 if ((op = get_op(*l)) != -1) {
1917 m->in_op |= op;
1918 l++;
1919 }
1920 if (*l == '(') {
1921 m->in_op |= FILE_OPINDIRECT;
1922 l++;
1923 }
1924 if (isdigit((unsigned char)*l) || *l == '-') {
1925 m->in_offset = (int32_t)strtol(l, &t, 0);
1926 if (l == t)
1927 if (ms->flags & MAGIC_CHECK)
1928 file_magwarn(ms,
1929 "in_offset `%s' invalid", l);
1930 l = t;
1931 }
1932 if (*l++ != ')' ||
1933 ((m->in_op & FILE_OPINDIRECT) && *l++ != ')'))
1934 if (ms->flags & MAGIC_CHECK)
1935 file_magwarn(ms,
1936 "missing ')' in indirect offset");
1937 }
1938 EATAB;
1939
1940 #ifdef ENABLE_CONDITIONALS
1941 m->cond = get_cond(l, &l);
1942 if (check_cond(ms, m->cond, cont_level) == -1)
1943 return -1;
1944
1945 EATAB;
1946 #endif
1947
1948 /*
1949 * Parse the type.
1950 */
1951 if (*l == 'u') {
1952 /*
1953 * Try it as a keyword type prefixed by "u"; match what
1954 * follows the "u". If that fails, try it as an SUS
1955 * integer type.
1956 */
1957 m->type = get_type(type_tbl, l + 1, &l);
1958 if (m->type == FILE_INVALID) {
1959 /*
1960 * Not a keyword type; parse it as an SUS type,
1961 * 'u' possibly followed by a number or C/S/L.
1962 */
1963 m->type = get_standard_integer_type(l, &l);
1964 }
1965 /* It's unsigned. */
1966 if (m->type != FILE_INVALID)
1967 m->flag |= UNSIGNED;
1968 } else {
1969 /*
1970 * Try it as a keyword type. If that fails, try it as
1971 * an SUS integer type if it begins with "d" or as an
1972 * SUS string type if it begins with "s". In any case,
1973 * it's not unsigned.
1974 */
1975 m->type = get_type(type_tbl, l, &l);
1976 if (m->type == FILE_INVALID) {
1977 /*
1978 * Not a keyword type; parse it as an SUS type,
1979 * either 'd' possibly followed by a number or
1980 * C/S/L, or just 's'.
1981 */
1982 if (*l == 'd')
1983 m->type = get_standard_integer_type(l, &l);
1984 else if (*l == 's' && !isalpha((unsigned char)l[1])) {
1985 m->type = FILE_STRING;
1986 ++l;
1987 }
1988 }
1989 }
1990
1991 if (m->type == FILE_INVALID) {
1992 /* Not found - try it as a special keyword. */
1993 m->type = get_type(special_tbl, l, &l);
1994 }
1995
1996 if (m->type == FILE_INVALID) {
1997 if (ms->flags & MAGIC_CHECK)
1998 file_magwarn(ms, "type `%s' invalid", l);
1999 return -1;
2000 }
2001
2002 /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2003 /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2004
2005 m->mask_op = 0;
2006 if (*l == '~') {
2007 if (!IS_STRING(m->type))
2008 m->mask_op |= FILE_OPINVERSE;
2009 else if (ms->flags & MAGIC_CHECK)
2010 file_magwarn(ms, "'~' invalid for string types");
2011 ++l;
2012 }
2013 m->str_range = 0;
2014 m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2015 if ((op = get_op(*l)) != -1) {
2016 if (IS_STRING(m->type)) {
2017 int r;
2018
2019 if (op != FILE_OPDIVIDE) {
2020 if (ms->flags & MAGIC_CHECK)
2021 file_magwarn(ms,
2022 "invalid string/indirect op: "
2023 "`%c'", *t);
2024 return -1;
2025 }
2026
2027 if (m->type == FILE_INDIRECT)
2028 r = parse_indirect_modifier(ms, m, &l);
2029 else
2030 r = parse_string_modifier(ms, m, &l);
2031 if (r == -1)
2032 return -1;
2033 } else
2034 parse_op_modifier(ms, m, &l, op);
2035 }
2036
2037 /*
2038 * We used to set mask to all 1's here, instead let's just not do
2039 * anything if mask = 0 (unless you have a better idea)
2040 */
2041 EATAB;
2042
2043 switch (*l) {
2044 case '>':
2045 case '<':
2046 m->reln = *l;
2047 ++l;
2048 if (*l == '=') {
2049 if (ms->flags & MAGIC_CHECK) {
2050 file_magwarn(ms, "%c= not supported",
2051 m->reln);
2052 return -1;
2053 }
2054 ++l;
2055 }
2056 break;
2057 /* Old-style anding: "0 byte &0x80 dynamically linked" */
2058 case '&':
2059 case '^':
2060 case '=':
2061 m->reln = *l;
2062 ++l;
2063 if (*l == '=') {
2064 /* HP compat: ignore &= etc. */
2065 ++l;
2066 }
2067 break;
2068 case '!':
2069 m->reln = *l;
2070 ++l;
2071 break;
2072 default:
2073 m->reln = '='; /* the default relation */
2074 if (*l == 'x' && ((isascii((unsigned char)l[1]) &&
2075 isspace((unsigned char)l[1])) || !l[1])) {
2076 m->reln = *l;
2077 ++l;
2078 }
2079 break;
2080 }
2081 /*
2082 * Grab the value part, except for an 'x' reln.
2083 */
2084 if (m->reln != 'x' && getvalue(ms, m, &l, action))
2085 return -1;
2086
2087 /*
2088 * TODO finish this macro and start using it!
2089 * #define offsetcheck {if (offset > HOWMANY-1)
2090 * magwarn("offset too big"); }
2091 */
2092
2093 /*
2094 * Now get last part - the description
2095 */
2096 EATAB;
2097 if (l[0] == '\b') {
2098 ++l;
2099 m->flag |= NOSPACE;
2100 } else if ((l[0] == '\\') && (l[1] == 'b')) {
2101 ++l;
2102 ++l;
2103 m->flag |= NOSPACE;
2104 }
2105 for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); )
2106 continue;
2107 if (i == sizeof(m->desc)) {
2108 m->desc[sizeof(m->desc) - 1] = '\0';
2109 if (ms->flags & MAGIC_CHECK)
2110 file_magwarn(ms, "description `%s' truncated", m->desc);
2111 }
2112
2113 /*
2114 * We only do this check while compiling, or if any of the magic
2115 * files were not compiled.
2116 */
2117 if (ms->flags & MAGIC_CHECK) {
2118 if (check_format(ms, m) == -1)
2119 return -1;
2120 }
2121 #ifndef COMPILE_ONLY
2122 if (action == FILE_CHECK) {
2123 file_mdump(m);
2124 }
2125 #endif
2126 m->mimetype[0] = '\0'; /* initialise MIME type to none */
2127 return 0;
2128 }
2129
2130 /*
2131 * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2132 * if valid
2133 */
2134 private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line)2135 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line)
2136 {
2137 const char *l = line;
2138 char *el;
2139 unsigned long factor;
2140 struct magic *m = &me->mp[0];
2141
2142 if (m->factor_op != FILE_FACTOR_OP_NONE) {
2143 file_magwarn(ms,
2144 "Current entry already has a strength type: %c %d",
2145 m->factor_op, m->factor);
2146 return -1;
2147 }
2148 if (m->type == FILE_NAME) {
2149 file_magwarn(ms, "%s: Strength setting is not supported in "
2150 "\"name\" magic entries", m->value.s);
2151 return -1;
2152 }
2153 EATAB;
2154 switch (*l) {
2155 case FILE_FACTOR_OP_NONE:
2156 case FILE_FACTOR_OP_PLUS:
2157 case FILE_FACTOR_OP_MINUS:
2158 case FILE_FACTOR_OP_TIMES:
2159 case FILE_FACTOR_OP_DIV:
2160 m->factor_op = *l++;
2161 break;
2162 default:
2163 file_magwarn(ms, "Unknown factor op `%c'", *l);
2164 return -1;
2165 }
2166 EATAB;
2167 factor = strtoul(l, &el, 0);
2168 if (factor > 255) {
2169 file_magwarn(ms, "Too large factor `%lu'", factor);
2170 goto out;
2171 }
2172 if (*el && !isspace((unsigned char)*el)) {
2173 file_magwarn(ms, "Bad factor `%s'", l);
2174 goto out;
2175 }
2176 m->factor = (uint8_t)factor;
2177 if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2178 file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2179 m->factor_op, m->factor);
2180 goto out;
2181 }
2182 return 0;
2183 out:
2184 m->factor_op = FILE_FACTOR_OP_NONE;
2185 m->factor = 0;
2186 return -1;
2187 }
2188
2189 private int
goodchar(unsigned char x,const char * extra)2190 goodchar(unsigned char x, const char *extra)
2191 {
2192 return (isascii(x) && isalnum(x)) || strchr(extra, x);
2193 }
2194
2195 private int
parse_extra(struct magic_set * ms,struct magic_entry * me,const char * line,off_t off,size_t len,const char * name,const char * extra,int nt)2196 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2197 off_t off, size_t len, const char *name, const char *extra, int nt)
2198 {
2199 size_t i;
2200 const char *l = line;
2201 struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2202 char *buf = (char *)m + off;
2203
2204 if (buf[0] != '\0') {
2205 len = nt ? strlen(buf) : len;
2206 file_magwarn(ms, "Current entry already has a %s type "
2207 "`%.*s', new type `%s'", name, (int)len, buf, l);
2208 return -1;
2209 }
2210
2211 if (*m->desc == '\0') {
2212 file_magwarn(ms, "Current entry does not yet have a "
2213 "description for adding a %s type", name);
2214 return -1;
2215 }
2216
2217 EATAB;
2218 for (i = 0; *l && i < len && goodchar(*l, extra); buf[i++] = *l++)
2219 continue;
2220
2221 if (i == len && *l) {
2222 if (nt)
2223 buf[len - 1] = '\0';
2224 if (ms->flags & MAGIC_CHECK)
2225 file_magwarn(ms, "%s type `%s' truncated %"
2226 SIZE_T_FORMAT "u", name, line, i);
2227 } else {
2228 if (!isspace((unsigned char)*l) && !goodchar(*l, extra))
2229 file_magwarn(ms, "%s type `%s' has bad char '%c'",
2230 name, line, *l);
2231 if (nt)
2232 buf[i] = '\0';
2233 }
2234
2235 if (i > 0)
2236 return 0;
2237
2238 file_magerror(ms, "Bad magic entry '%s'", line);
2239 return -1;
2240 }
2241
2242 /*
2243 * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2244 * magic[index - 1]
2245 */
2246 private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line)2247 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line)
2248 {
2249 struct magic *m = &me->mp[0];
2250
2251 return parse_extra(ms, me, line, offsetof(struct magic, apple),
2252 sizeof(m->apple), "APPLE", "!+-./", 0);
2253 }
2254
2255 /*
2256 * parse a MIME annotation line from magic file, put into magic[index - 1]
2257 * if valid
2258 */
2259 private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line)2260 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line)
2261 {
2262 struct magic *m = &me->mp[0];
2263
2264 return parse_extra(ms, me, line, offsetof(struct magic, mimetype),
2265 sizeof(m->mimetype), "MIME", "+-/.", 1);
2266 }
2267
2268 private int
check_format_type(const char * ptr,int type)2269 check_format_type(const char *ptr, int type)
2270 {
2271 int quad = 0, h;
2272 if (*ptr == '\0') {
2273 /* Missing format string; bad */
2274 return -1;
2275 }
2276
2277 switch (file_formats[type]) {
2278 case FILE_FMT_QUAD:
2279 quad = 1;
2280 /*FALLTHROUGH*/
2281 case FILE_FMT_NUM:
2282 if (quad == 0) {
2283 switch (type) {
2284 case FILE_BYTE:
2285 h = 2;
2286 break;
2287 case FILE_SHORT:
2288 case FILE_BESHORT:
2289 case FILE_LESHORT:
2290 h = 1;
2291 break;
2292 case FILE_LONG:
2293 case FILE_BELONG:
2294 case FILE_LELONG:
2295 case FILE_MELONG:
2296 case FILE_LEID3:
2297 case FILE_BEID3:
2298 case FILE_INDIRECT:
2299 h = 0;
2300 break;
2301 default:
2302 abort();
2303 }
2304 } else
2305 h = 0;
2306 if (*ptr == '-')
2307 ptr++;
2308 if (*ptr == '.')
2309 ptr++;
2310 while (isdigit((unsigned char)*ptr)) ptr++;
2311 if (*ptr == '.')
2312 ptr++;
2313 while (isdigit((unsigned char)*ptr)) ptr++;
2314 if (quad) {
2315 if (*ptr++ != 'l')
2316 return -1;
2317 if (*ptr++ != 'l')
2318 return -1;
2319 }
2320
2321 switch (*ptr++) {
2322 #ifdef STRICT_FORMAT /* "long" formats are int formats for us */
2323 /* so don't accept the 'l' modifier */
2324 case 'l':
2325 switch (*ptr++) {
2326 case 'i':
2327 case 'd':
2328 case 'u':
2329 case 'o':
2330 case 'x':
2331 case 'X':
2332 return h != 0 ? -1 : 0;
2333 default:
2334 return -1;
2335 }
2336
2337 /*
2338 * Don't accept h and hh modifiers. They make writing
2339 * magic entries more complicated, for very little benefit
2340 */
2341 case 'h':
2342 if (h-- <= 0)
2343 return -1;
2344 switch (*ptr++) {
2345 case 'h':
2346 if (h-- <= 0)
2347 return -1;
2348 switch (*ptr++) {
2349 case 'i':
2350 case 'd':
2351 case 'u':
2352 case 'o':
2353 case 'x':
2354 case 'X':
2355 return 0;
2356 default:
2357 return -1;
2358 }
2359 case 'i':
2360 case 'd':
2361 case 'u':
2362 case 'o':
2363 case 'x':
2364 case 'X':
2365 return h != 0 ? -1 : 0;
2366 default:
2367 return -1;
2368 }
2369 #endif
2370 case 'c':
2371 return h != 2 ? -1 : 0;
2372 case 'i':
2373 case 'd':
2374 case 'u':
2375 case 'o':
2376 case 'x':
2377 case 'X':
2378 #ifdef STRICT_FORMAT
2379 return h != 0 ? -1 : 0;
2380 #else
2381 return 0;
2382 #endif
2383 default:
2384 return -1;
2385 }
2386
2387 case FILE_FMT_FLOAT:
2388 case FILE_FMT_DOUBLE:
2389 if (*ptr == '-')
2390 ptr++;
2391 if (*ptr == '.')
2392 ptr++;
2393 while (isdigit((unsigned char)*ptr)) ptr++;
2394 if (*ptr == '.')
2395 ptr++;
2396 while (isdigit((unsigned char)*ptr)) ptr++;
2397
2398 switch (*ptr++) {
2399 case 'e':
2400 case 'E':
2401 case 'f':
2402 case 'F':
2403 case 'g':
2404 case 'G':
2405 return 0;
2406
2407 default:
2408 return -1;
2409 }
2410
2411
2412 case FILE_FMT_STR:
2413 if (*ptr == '-')
2414 ptr++;
2415 while (isdigit((unsigned char )*ptr))
2416 ptr++;
2417 if (*ptr == '.') {
2418 ptr++;
2419 while (isdigit((unsigned char )*ptr))
2420 ptr++;
2421 }
2422
2423 switch (*ptr++) {
2424 case 's':
2425 return 0;
2426 default:
2427 return -1;
2428 }
2429
2430 default:
2431 /* internal error */
2432 abort();
2433 }
2434 /*NOTREACHED*/
2435 return -1;
2436 }
2437
2438 /*
2439 * Check that the optional printf format in description matches
2440 * the type of the magic.
2441 */
2442 private int
check_format(struct magic_set * ms,struct magic * m)2443 check_format(struct magic_set *ms, struct magic *m)
2444 {
2445 char *ptr;
2446
2447 for (ptr = m->desc; *ptr; ptr++)
2448 if (*ptr == '%')
2449 break;
2450 if (*ptr == '\0') {
2451 /* No format string; ok */
2452 return 1;
2453 }
2454
2455 assert(file_nformats == file_nnames);
2456
2457 if (m->type >= file_nformats) {
2458 file_magwarn(ms, "Internal error inconsistency between "
2459 "m->type and format strings");
2460 return -1;
2461 }
2462 if (file_formats[m->type] == FILE_FMT_NONE) {
2463 file_magwarn(ms, "No format string for `%s' with description "
2464 "`%s'", m->desc, file_names[m->type]);
2465 return -1;
2466 }
2467
2468 ptr++;
2469 if (check_format_type(ptr, m->type) == -1) {
2470 /*
2471 * TODO: this error message is unhelpful if the format
2472 * string is not one character long
2473 */
2474 file_magwarn(ms, "Printf format `%c' is not valid for type "
2475 "`%s' in description `%s'", *ptr ? *ptr : '?',
2476 file_names[m->type], m->desc);
2477 return -1;
2478 }
2479
2480 for (; *ptr; ptr++) {
2481 if (*ptr == '%') {
2482 file_magwarn(ms,
2483 "Too many format strings (should have at most one) "
2484 "for `%s' with description `%s'",
2485 file_names[m->type], m->desc);
2486 return -1;
2487 }
2488 }
2489 return 0;
2490 }
2491
2492 /*
2493 * Read a numeric value from a pointer, into the value union of a magic
2494 * pointer, according to the magic type. Update the string pointer to point
2495 * just after the number read. Return 0 for success, non-zero for failure.
2496 */
2497 private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2498 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2499 {
2500 switch (m->type) {
2501 case FILE_BESTRING16:
2502 case FILE_LESTRING16:
2503 case FILE_STRING:
2504 case FILE_PSTRING:
2505 case FILE_REGEX:
2506 case FILE_SEARCH:
2507 case FILE_NAME:
2508 case FILE_USE:
2509 *p = getstr(ms, m, *p, action == FILE_COMPILE);
2510 if (*p == NULL) {
2511 if (ms->flags & MAGIC_CHECK)
2512 file_magwarn(ms, "cannot get string from `%s'",
2513 m->value.s);
2514 return -1;
2515 }
2516 if (m->type == FILE_REGEX) {
2517 file_regex_t rx;
2518 int rc = file_regcomp(&rx, m->value.s, REG_EXTENDED);
2519 if (rc) {
2520 if (ms->flags & MAGIC_CHECK)
2521 file_regerror(&rx, rc, ms);
2522 }
2523 file_regfree(&rx);
2524 return rc ? -1 : 0;
2525 }
2526 return 0;
2527 case FILE_FLOAT:
2528 case FILE_BEFLOAT:
2529 case FILE_LEFLOAT:
2530 if (m->reln != 'x') {
2531 char *ep;
2532 #ifdef HAVE_STRTOF
2533 m->value.f = strtof(*p, &ep);
2534 #else
2535 m->value.f = (float)strtod(*p, &ep);
2536 #endif
2537 *p = ep;
2538 }
2539 return 0;
2540 case FILE_DOUBLE:
2541 case FILE_BEDOUBLE:
2542 case FILE_LEDOUBLE:
2543 if (m->reln != 'x') {
2544 char *ep;
2545 m->value.d = strtod(*p, &ep);
2546 *p = ep;
2547 }
2548 return 0;
2549 default:
2550 if (m->reln != 'x') {
2551 char *ep;
2552 m->value.q = file_signextend(ms, m,
2553 (uint64_t)strtoull(*p, &ep, 0));
2554 *p = ep;
2555 eatsize(p);
2556 }
2557 return 0;
2558 }
2559 }
2560
2561 /*
2562 * Convert a string containing C character escapes. Stop at an unescaped
2563 * space or tab.
2564 * Copy the converted version to "m->value.s", and the length in m->vallen.
2565 * Return updated scan pointer as function result. Warn if set.
2566 */
2567 private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)2568 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
2569 {
2570 const char *origs = s;
2571 char *p = m->value.s;
2572 size_t plen = sizeof(m->value.s);
2573 char *origp = p;
2574 char *pmax = p + plen - 1;
2575 int c;
2576 int val;
2577
2578 while ((c = *s++) != '\0') {
2579 if (isspace((unsigned char) c))
2580 break;
2581 if (p >= pmax) {
2582 file_error(ms, 0, "string too long: `%s'", origs);
2583 return NULL;
2584 }
2585 if (c == '\\') {
2586 switch(c = *s++) {
2587
2588 case '\0':
2589 if (warn)
2590 file_magwarn(ms, "incomplete escape");
2591 goto out;
2592
2593 case '\t':
2594 if (warn) {
2595 file_magwarn(ms,
2596 "escaped tab found, use \\t instead");
2597 warn = 0; /* already did */
2598 }
2599 /*FALLTHROUGH*/
2600 default:
2601 if (warn) {
2602 if (isprint((unsigned char)c)) {
2603 /* Allow escaping of
2604 * ``relations'' */
2605 if (strchr("<>&^=!", c) == NULL
2606 && (m->type != FILE_REGEX ||
2607 strchr("[]().*?^$|{}", c)
2608 == NULL)) {
2609 file_magwarn(ms, "no "
2610 "need to escape "
2611 "`%c'", c);
2612 }
2613 } else {
2614 file_magwarn(ms,
2615 "unknown escape sequence: "
2616 "\\%03o", c);
2617 }
2618 }
2619 /*FALLTHROUGH*/
2620 /* space, perhaps force people to use \040? */
2621 case ' ':
2622 #if 0
2623 /*
2624 * Other things people escape, but shouldn't need to,
2625 * so we disallow them
2626 */
2627 case '\'':
2628 case '"':
2629 case '?':
2630 #endif
2631 /* Relations */
2632 case '>':
2633 case '<':
2634 case '&':
2635 case '^':
2636 case '=':
2637 case '!':
2638 /* and baskslash itself */
2639 case '\\':
2640 *p++ = (char) c;
2641 break;
2642
2643 case 'a':
2644 *p++ = '\a';
2645 break;
2646
2647 case 'b':
2648 *p++ = '\b';
2649 break;
2650
2651 case 'f':
2652 *p++ = '\f';
2653 break;
2654
2655 case 'n':
2656 *p++ = '\n';
2657 break;
2658
2659 case 'r':
2660 *p++ = '\r';
2661 break;
2662
2663 case 't':
2664 *p++ = '\t';
2665 break;
2666
2667 case 'v':
2668 *p++ = '\v';
2669 break;
2670
2671 /* \ and up to 3 octal digits */
2672 case '0':
2673 case '1':
2674 case '2':
2675 case '3':
2676 case '4':
2677 case '5':
2678 case '6':
2679 case '7':
2680 val = c - '0';
2681 c = *s++; /* try for 2 */
2682 if (c >= '0' && c <= '7') {
2683 val = (val << 3) | (c - '0');
2684 c = *s++; /* try for 3 */
2685 if (c >= '0' && c <= '7')
2686 val = (val << 3) | (c-'0');
2687 else
2688 --s;
2689 }
2690 else
2691 --s;
2692 *p++ = (char)val;
2693 break;
2694
2695 /* \x and up to 2 hex digits */
2696 case 'x':
2697 val = 'x'; /* Default if no digits */
2698 c = hextoint(*s++); /* Get next char */
2699 if (c >= 0) {
2700 val = c;
2701 c = hextoint(*s++);
2702 if (c >= 0)
2703 val = (val << 4) + c;
2704 else
2705 --s;
2706 } else
2707 --s;
2708 *p++ = (char)val;
2709 break;
2710 }
2711 } else
2712 *p++ = (char)c;
2713 }
2714 out:
2715 *p = '\0';
2716 m->vallen = CAST(unsigned char, (p - origp));
2717 if (m->type == FILE_PSTRING)
2718 m->vallen += (unsigned char)file_pstring_length_size(m);
2719 return s;
2720 }
2721
2722
2723 /* Single hex char to int; -1 if not a hex char. */
2724 private int
hextoint(int c)2725 hextoint(int c)
2726 {
2727 if (!isascii((unsigned char) c))
2728 return -1;
2729 if (isdigit((unsigned char) c))
2730 return c - '0';
2731 if ((c >= 'a') && (c <= 'f'))
2732 return c + 10 - 'a';
2733 if (( c>= 'A') && (c <= 'F'))
2734 return c + 10 - 'A';
2735 return -1;
2736 }
2737
2738
2739 /*
2740 * Print a string containing C character escapes.
2741 */
2742 protected void
file_showstr(FILE * fp,const char * s,size_t len)2743 file_showstr(FILE *fp, const char *s, size_t len)
2744 {
2745 char c;
2746
2747 for (;;) {
2748 if (len == ~0U) {
2749 c = *s++;
2750 if (c == '\0')
2751 break;
2752 }
2753 else {
2754 if (len-- == 0)
2755 break;
2756 c = *s++;
2757 }
2758 if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */
2759 (void) fputc(c, fp);
2760 else {
2761 (void) fputc('\\', fp);
2762 switch (c) {
2763 case '\a':
2764 (void) fputc('a', fp);
2765 break;
2766
2767 case '\b':
2768 (void) fputc('b', fp);
2769 break;
2770
2771 case '\f':
2772 (void) fputc('f', fp);
2773 break;
2774
2775 case '\n':
2776 (void) fputc('n', fp);
2777 break;
2778
2779 case '\r':
2780 (void) fputc('r', fp);
2781 break;
2782
2783 case '\t':
2784 (void) fputc('t', fp);
2785 break;
2786
2787 case '\v':
2788 (void) fputc('v', fp);
2789 break;
2790
2791 default:
2792 (void) fprintf(fp, "%.3o", c & 0377);
2793 break;
2794 }
2795 }
2796 }
2797 }
2798
2799 /*
2800 * eatsize(): Eat the size spec from a number [eg. 10UL]
2801 */
2802 private void
eatsize(const char ** p)2803 eatsize(const char **p)
2804 {
2805 const char *l = *p;
2806
2807 if (LOWCASE(*l) == 'u')
2808 l++;
2809
2810 switch (LOWCASE(*l)) {
2811 case 'l': /* long */
2812 case 's': /* short */
2813 case 'h': /* short */
2814 case 'b': /* char/byte */
2815 case 'c': /* char/byte */
2816 l++;
2817 /*FALLTHROUGH*/
2818 default:
2819 break;
2820 }
2821
2822 *p = l;
2823 }
2824
2825 /*
2826 * handle a buffer containing a compiled file.
2827 */
2828 private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)2829 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
2830 {
2831 struct magic_map *map;
2832
2833 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
2834 file_oomem(ms, sizeof(*map));
2835 return NULL;
2836 }
2837 map->len = len;
2838 map->p = buf;
2839 map->type = MAP_TYPE_USER;
2840 if (check_buffer(ms, map, "buffer") != 0) {
2841 apprentice_unmap(map);
2842 return NULL;
2843 }
2844 return map;
2845 }
2846
2847 /*
2848 * handle a compiled file.
2849 */
2850
2851 private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)2852 apprentice_map(struct magic_set *ms, const char *fn)
2853 {
2854 int fd;
2855 struct stat st;
2856 char *dbname = NULL;
2857 struct magic_map *map;
2858
2859 fd = -1;
2860 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
2861 file_oomem(ms, sizeof(*map));
2862 goto error;
2863 }
2864
2865 dbname = mkdbname(ms, fn, 0);
2866 if (dbname == NULL)
2867 goto error;
2868
2869 if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
2870 goto error;
2871
2872 if (fstat(fd, &st) == -1) {
2873 file_error(ms, errno, "cannot stat `%s'", dbname);
2874 goto error;
2875 }
2876 if (st.st_size < 8 || st.st_size > MAXMAGIC_SIZE) {
2877 file_error(ms, 0, "file `%s' is too %s", dbname,
2878 st.st_size < 8 ? "small" : "large");
2879 goto error;
2880 }
2881
2882 map->len = (size_t)st.st_size;
2883 #ifdef QUICK
2884 if ((map->p = mmap(0, (size_t)st.st_size, PROT_READ|PROT_WRITE,
2885 MAP_PRIVATE|MAP_FILE, fd, (off_t)0)) == MAP_FAILED) {
2886 file_error(ms, errno, "cannot map `%s'", dbname);
2887 goto error;
2888 }
2889 map->type = MAP_TYPE_MMAP;
2890 #else
2891 if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
2892 file_oomem(ms, map->len);
2893 goto error;
2894 }
2895 if (read(fd, map->p, map->len) != (ssize_t)map->len) {
2896 file_badread(ms);
2897 goto error;
2898 }
2899 map->type = MAP_TYPE_MALLOC;
2900 #define RET 1
2901 #endif
2902 (void)close(fd);
2903 fd = -1;
2904
2905 if (check_buffer(ms, map, dbname) != 0)
2906 goto error;
2907
2908 free(dbname);
2909 return map;
2910
2911 error:
2912 if (fd != -1)
2913 (void)close(fd);
2914 apprentice_unmap(map);
2915 free(dbname);
2916 return NULL;
2917 }
2918
2919 private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)2920 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
2921 {
2922 uint32_t *ptr;
2923 uint32_t entries, nentries;
2924 uint32_t version;
2925 int i, needsbyteswap;
2926
2927 ptr = CAST(uint32_t *, map->p);
2928 if (*ptr != MAGICNO) {
2929 if (swap4(*ptr) != MAGICNO) {
2930 file_error(ms, 0, "bad magic in `%s'", dbname);
2931 return -1;
2932 }
2933 needsbyteswap = 1;
2934 } else
2935 needsbyteswap = 0;
2936 if (needsbyteswap)
2937 version = swap4(ptr[1]);
2938 else
2939 version = ptr[1];
2940 if (version != VERSIONNO) {
2941 file_error(ms, 0, "File %s supports only version %d magic "
2942 "files. `%s' is version %d", VERSION,
2943 VERSIONNO, dbname, version);
2944 return -1;
2945 }
2946 entries = (uint32_t)(map->len / sizeof(struct magic));
2947 if ((entries * sizeof(struct magic)) != map->len) {
2948 file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
2949 "a multiple of %" SIZE_T_FORMAT "u",
2950 dbname, map->len, sizeof(struct magic));
2951 return -1;
2952 }
2953 map->magic[0] = CAST(struct magic *, map->p) + 1;
2954 nentries = 0;
2955 for (i = 0; i < MAGIC_SETS; i++) {
2956 if (needsbyteswap)
2957 map->nmagic[i] = swap4(ptr[i + 2]);
2958 else
2959 map->nmagic[i] = ptr[i + 2];
2960 if (i != MAGIC_SETS - 1)
2961 map->magic[i + 1] = map->magic[i] + map->nmagic[i];
2962 nentries += map->nmagic[i];
2963 }
2964 if (entries != nentries + 1) {
2965 file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
2966 dbname, entries, nentries + 1);
2967 return -1;
2968 }
2969 if (needsbyteswap)
2970 for (i = 0; i < MAGIC_SETS; i++)
2971 byteswap(map->magic[i], map->nmagic[i]);
2972 return 0;
2973 }
2974
2975 /*
2976 * handle an mmaped file.
2977 */
2978 private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)2979 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
2980 {
2981 static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
2982 static const size_t m = sizeof(**map->magic);
2983 int fd = -1;
2984 size_t len;
2985 char *dbname;
2986 int rv = -1;
2987 uint32_t i;
2988 union {
2989 struct magic m;
2990 uint32_t h[2 + MAGIC_SETS];
2991 } hdr;
2992
2993 dbname = mkdbname(ms, fn, 1);
2994
2995 if (dbname == NULL)
2996 goto out;
2997
2998 if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
2999 {
3000 file_error(ms, errno, "cannot open `%s'", dbname);
3001 goto out;
3002 }
3003 memset(&hdr, 0, sizeof(hdr));
3004 hdr.h[0] = MAGICNO;
3005 hdr.h[1] = VERSIONNO;
3006 memcpy(hdr.h + 2, map->nmagic, nm);
3007
3008 if (write(fd, &hdr, sizeof(hdr)) != (ssize_t)sizeof(hdr)) {
3009 file_error(ms, errno, "error writing `%s'", dbname);
3010 goto out;
3011 }
3012
3013 for (i = 0; i < MAGIC_SETS; i++) {
3014 len = m * map->nmagic[i];
3015 if (write(fd, map->magic[i], len) != (ssize_t)len) {
3016 file_error(ms, errno, "error writing `%s'", dbname);
3017 goto out;
3018 }
3019 }
3020
3021 if (fd != -1)
3022 (void)close(fd);
3023 rv = 0;
3024 out:
3025 free(dbname);
3026 return rv;
3027 }
3028
3029 private const char ext[] = ".mgc";
3030 /*
3031 * make a dbname
3032 */
3033 private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3034 mkdbname(struct magic_set *ms, const char *fn, int strip)
3035 {
3036 const char *p, *q;
3037 char *buf;
3038
3039 if (strip) {
3040 if ((p = strrchr(fn, '/')) != NULL)
3041 fn = ++p;
3042 }
3043
3044 for (q = fn; *q; q++)
3045 continue;
3046 /* Look for .mgc */
3047 for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3048 if (*p != *q)
3049 break;
3050
3051 /* Did not find .mgc, restore q */
3052 if (p >= ext)
3053 while (*q)
3054 q++;
3055
3056 q++;
3057 /* Compatibility with old code that looked in .mime */
3058 if (ms->flags & MAGIC_MIME) {
3059 if (asprintf(&buf, "%.*s.mime%s", (int)(q - fn), fn, ext) < 0)
3060 return NULL;
3061 if (access(buf, R_OK) != -1) {
3062 ms->flags &= MAGIC_MIME_TYPE;
3063 return buf;
3064 }
3065 free(buf);
3066 }
3067 if (asprintf(&buf, "%.*s%s", (int)(q - fn), fn, ext) < 0)
3068 return NULL;
3069
3070 /* Compatibility with old code that looked in .mime */
3071 if (strstr(p, ".mime") != NULL)
3072 ms->flags &= MAGIC_MIME_TYPE;
3073 return buf;
3074 }
3075
3076 /*
3077 * Byteswap an mmap'ed file if needed
3078 */
3079 private void
byteswap(struct magic * magic,uint32_t nmagic)3080 byteswap(struct magic *magic, uint32_t nmagic)
3081 {
3082 uint32_t i;
3083 for (i = 0; i < nmagic; i++)
3084 bs1(&magic[i]);
3085 }
3086
3087 /*
3088 * swap a short
3089 */
3090 private uint16_t
swap2(uint16_t sv)3091 swap2(uint16_t sv)
3092 {
3093 uint16_t rv;
3094 uint8_t *s = (uint8_t *)(void *)&sv;
3095 uint8_t *d = (uint8_t *)(void *)&rv;
3096 d[0] = s[1];
3097 d[1] = s[0];
3098 return rv;
3099 }
3100
3101 /*
3102 * swap an int
3103 */
3104 private uint32_t
swap4(uint32_t sv)3105 swap4(uint32_t sv)
3106 {
3107 uint32_t rv;
3108 uint8_t *s = (uint8_t *)(void *)&sv;
3109 uint8_t *d = (uint8_t *)(void *)&rv;
3110 d[0] = s[3];
3111 d[1] = s[2];
3112 d[2] = s[1];
3113 d[3] = s[0];
3114 return rv;
3115 }
3116
3117 /*
3118 * swap a quad
3119 */
3120 private uint64_t
swap8(uint64_t sv)3121 swap8(uint64_t sv)
3122 {
3123 uint64_t rv;
3124 uint8_t *s = (uint8_t *)(void *)&sv;
3125 uint8_t *d = (uint8_t *)(void *)&rv;
3126 #if 0
3127 d[0] = s[3];
3128 d[1] = s[2];
3129 d[2] = s[1];
3130 d[3] = s[0];
3131 d[4] = s[7];
3132 d[5] = s[6];
3133 d[6] = s[5];
3134 d[7] = s[4];
3135 #else
3136 d[0] = s[7];
3137 d[1] = s[6];
3138 d[2] = s[5];
3139 d[3] = s[4];
3140 d[4] = s[3];
3141 d[5] = s[2];
3142 d[6] = s[1];
3143 d[7] = s[0];
3144 #endif
3145 return rv;
3146 }
3147
3148 /*
3149 * byteswap a single magic entry
3150 */
3151 private void
bs1(struct magic * m)3152 bs1(struct magic *m)
3153 {
3154 m->cont_level = swap2(m->cont_level);
3155 m->offset = swap4((uint32_t)m->offset);
3156 m->in_offset = swap4((uint32_t)m->in_offset);
3157 m->lineno = swap4((uint32_t)m->lineno);
3158 if (IS_STRING(m->type)) {
3159 m->str_range = swap4(m->str_range);
3160 m->str_flags = swap4(m->str_flags);
3161 }
3162 else {
3163 m->value.q = swap8(m->value.q);
3164 m->num_mask = swap8(m->num_mask);
3165 }
3166 }
3167
3168 protected size_t
file_pstring_length_size(const struct magic * m)3169 file_pstring_length_size(const struct magic *m)
3170 {
3171 switch (m->str_flags & PSTRING_LEN) {
3172 case PSTRING_1_LE:
3173 return 1;
3174 case PSTRING_2_LE:
3175 case PSTRING_2_BE:
3176 return 2;
3177 case PSTRING_4_LE:
3178 case PSTRING_4_BE:
3179 return 4;
3180 default:
3181 abort(); /* Impossible */
3182 return 1;
3183 }
3184 }
3185 protected size_t
file_pstring_get_length(const struct magic * m,const char * s)3186 file_pstring_get_length(const struct magic *m, const char *s)
3187 {
3188 size_t len = 0;
3189
3190 switch (m->str_flags & PSTRING_LEN) {
3191 case PSTRING_1_LE:
3192 len = *s;
3193 break;
3194 case PSTRING_2_LE:
3195 len = (s[1] << 8) | s[0];
3196 break;
3197 case PSTRING_2_BE:
3198 len = (s[0] << 8) | s[1];
3199 break;
3200 case PSTRING_4_LE:
3201 len = (s[3] << 24) | (s[2] << 16) | (s[1] << 8) | s[0];
3202 break;
3203 case PSTRING_4_BE:
3204 len = (s[0] << 24) | (s[1] << 16) | (s[2] << 8) | s[3];
3205 break;
3206 default:
3207 abort(); /* Impossible */
3208 }
3209
3210 if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF)
3211 len -= file_pstring_length_size(m);
3212
3213 return len;
3214 }
3215
3216 protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3217 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3218 {
3219 uint32_t i, j;
3220 struct mlist *mlist, *ml;
3221
3222 mlist = ms->mlist[1];
3223
3224 for (ml = mlist->next; ml != mlist; ml = ml->next) {
3225 struct magic *ma = ml->magic;
3226 uint32_t nma = ml->nmagic;
3227 for (i = 0; i < nma; i++) {
3228 if (ma[i].type != FILE_NAME)
3229 continue;
3230 if (strcmp(ma[i].value.s, name) == 0) {
3231 v->magic = &ma[i];
3232 for (j = i + 1; j < nma; j++)
3233 if (ma[j].cont_level == 0)
3234 break;
3235 v->nmagic = j - i;
3236 return 0;
3237 }
3238 }
3239 }
3240 return -1;
3241 }
3242