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 1.272 2018/06/22 20:39:50 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_USER 0
90 #define MAP_TYPE_MALLOC 1
91 #define MAP_TYPE_MMAP 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, const char **);
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 private int parse_ext(struct magic_set *, struct magic_entry *, const char *);
153
154
155 private size_t magicsize = sizeof(struct magic);
156
157 private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc";
158
159 private struct {
160 const char *name;
161 size_t len;
162 int (*fun)(struct magic_set *, struct magic_entry *, const char *);
163 } bang[] = {
164 #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name }
165 DECLARE_FIELD(mime),
166 DECLARE_FIELD(apple),
167 DECLARE_FIELD(ext),
168 DECLARE_FIELD(strength),
169 #undef DECLARE_FIELD
170 { NULL, 0, NULL }
171 };
172
173 #ifdef COMPILE_ONLY
174
175 int main(int, char *[]);
176
177 int
main(int argc,char * argv[])178 main(int argc, char *argv[])
179 {
180 int ret;
181 struct magic_set *ms;
182 char *progname;
183
184 if ((progname = strrchr(argv[0], '/')) != NULL)
185 progname++;
186 else
187 progname = argv[0];
188
189 if (argc != 2) {
190 (void)fprintf(stderr, "Usage: %s file\n", progname);
191 return 1;
192 }
193
194 if ((ms = magic_open(MAGIC_CHECK)) == NULL) {
195 (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
196 return 1;
197 }
198 ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0;
199 if (ret == 1)
200 (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms));
201 magic_close(ms);
202 return ret;
203 }
204 #endif /* COMPILE_ONLY */
205
206 struct type_tbl_s {
207 const char name[16];
208 const size_t len;
209 const int type;
210 const int format;
211 };
212
213 /*
214 * XXX - the actual Single UNIX Specification says that "long" means "long",
215 * as in the C data type, but we treat it as meaning "4-byte integer".
216 * Given that the OS X version of file 5.04 did the same, I guess that passes
217 * the actual test; having "long" be dependent on how big a "long" is on
218 * the machine running "file" is silly.
219 */
220 static const struct type_tbl_s type_tbl[] = {
221 # define XX(s) s, (sizeof(s) - 1)
222 # define XX_NULL "", 0
223 { XX("invalid"), FILE_INVALID, FILE_FMT_NONE },
224 { XX("byte"), FILE_BYTE, FILE_FMT_NUM },
225 { XX("short"), FILE_SHORT, FILE_FMT_NUM },
226 { XX("default"), FILE_DEFAULT, FILE_FMT_NONE },
227 { XX("long"), FILE_LONG, FILE_FMT_NUM },
228 { XX("string"), FILE_STRING, FILE_FMT_STR },
229 { XX("date"), FILE_DATE, FILE_FMT_STR },
230 { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM },
231 { XX("belong"), FILE_BELONG, FILE_FMT_NUM },
232 { XX("bedate"), FILE_BEDATE, FILE_FMT_STR },
233 { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM },
234 { XX("lelong"), FILE_LELONG, FILE_FMT_NUM },
235 { XX("ledate"), FILE_LEDATE, FILE_FMT_STR },
236 { XX("pstring"), FILE_PSTRING, FILE_FMT_STR },
237 { XX("ldate"), FILE_LDATE, FILE_FMT_STR },
238 { XX("beldate"), FILE_BELDATE, FILE_FMT_STR },
239 { XX("leldate"), FILE_LELDATE, FILE_FMT_STR },
240 { XX("regex"), FILE_REGEX, FILE_FMT_STR },
241 { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR },
242 { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR },
243 { XX("search"), FILE_SEARCH, FILE_FMT_STR },
244 { XX("medate"), FILE_MEDATE, FILE_FMT_STR },
245 { XX("meldate"), FILE_MELDATE, FILE_FMT_STR },
246 { XX("melong"), FILE_MELONG, FILE_FMT_NUM },
247 { XX("quad"), FILE_QUAD, FILE_FMT_QUAD },
248 { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD },
249 { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD },
250 { XX("qdate"), FILE_QDATE, FILE_FMT_STR },
251 { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR },
252 { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR },
253 { XX("qldate"), FILE_QLDATE, FILE_FMT_STR },
254 { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR },
255 { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR },
256 { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT },
257 { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT },
258 { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT },
259 { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE },
260 { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE },
261 { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE },
262 { XX("leid3"), FILE_LEID3, FILE_FMT_NUM },
263 { XX("beid3"), FILE_BEID3, FILE_FMT_NUM },
264 { XX("indirect"), FILE_INDIRECT, FILE_FMT_NUM },
265 { XX("qwdate"), FILE_QWDATE, FILE_FMT_STR },
266 { XX("leqwdate"), FILE_LEQWDATE, FILE_FMT_STR },
267 { XX("beqwdate"), FILE_BEQWDATE, FILE_FMT_STR },
268 { XX("name"), FILE_NAME, FILE_FMT_NONE },
269 { XX("use"), FILE_USE, FILE_FMT_NONE },
270 { XX("clear"), FILE_CLEAR, FILE_FMT_NONE },
271 { XX("der"), FILE_DER, FILE_FMT_STR },
272 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
273 };
274
275 /*
276 * These are not types, and cannot be preceded by "u" to make them
277 * unsigned.
278 */
279 static const struct type_tbl_s special_tbl[] = {
280 { XX("der"), FILE_DER, FILE_FMT_STR },
281 { XX("name"), FILE_NAME, FILE_FMT_STR },
282 { XX("use"), FILE_USE, FILE_FMT_STR },
283 { XX_NULL, FILE_INVALID, FILE_FMT_NONE },
284 };
285 # undef XX
286 # undef XX_NULL
287
288 private int
get_type(const struct type_tbl_s * tbl,const char * l,const char ** t)289 get_type(const struct type_tbl_s *tbl, const char *l, const char **t)
290 {
291 const struct type_tbl_s *p;
292
293 for (p = tbl; p->len; p++) {
294 if (strncmp(l, p->name, p->len) == 0) {
295 if (t)
296 *t = l + p->len;
297 break;
298 }
299 }
300 return p->type;
301 }
302
303 private int
get_standard_integer_type(const char * l,const char ** t)304 get_standard_integer_type(const char *l, const char **t)
305 {
306 int type;
307
308 if (isalpha((unsigned char)l[1])) {
309 switch (l[1]) {
310 case 'C':
311 /* "dC" and "uC" */
312 type = FILE_BYTE;
313 break;
314 case 'S':
315 /* "dS" and "uS" */
316 type = FILE_SHORT;
317 break;
318 case 'I':
319 case 'L':
320 /*
321 * "dI", "dL", "uI", and "uL".
322 *
323 * XXX - the actual Single UNIX Specification says
324 * that "L" means "long", as in the C data type,
325 * but we treat it as meaning "4-byte integer".
326 * Given that the OS X version of file 5.04 did
327 * the same, I guess that passes the actual SUS
328 * validation suite; having "dL" be dependent on
329 * how big a "long" is on the machine running
330 * "file" is silly.
331 */
332 type = FILE_LONG;
333 break;
334 case 'Q':
335 /* "dQ" and "uQ" */
336 type = FILE_QUAD;
337 break;
338 default:
339 /* "d{anything else}", "u{anything else}" */
340 return FILE_INVALID;
341 }
342 l += 2;
343 } else if (isdigit((unsigned char)l[1])) {
344 /*
345 * "d{num}" and "u{num}"; we only support {num} values
346 * of 1, 2, 4, and 8 - the Single UNIX Specification
347 * doesn't say anything about whether arbitrary
348 * values should be supported, but both the Solaris 10
349 * and OS X Mountain Lion versions of file passed the
350 * Single UNIX Specification validation suite, and
351 * neither of them support values bigger than 8 or
352 * non-power-of-2 values.
353 */
354 if (isdigit((unsigned char)l[2])) {
355 /* Multi-digit, so > 9 */
356 return FILE_INVALID;
357 }
358 switch (l[1]) {
359 case '1':
360 type = FILE_BYTE;
361 break;
362 case '2':
363 type = FILE_SHORT;
364 break;
365 case '4':
366 type = FILE_LONG;
367 break;
368 case '8':
369 type = FILE_QUAD;
370 break;
371 default:
372 /* XXX - what about 3, 5, 6, or 7? */
373 return FILE_INVALID;
374 }
375 l += 2;
376 } else {
377 /*
378 * "d" or "u" by itself.
379 */
380 type = FILE_LONG;
381 ++l;
382 }
383 if (t)
384 *t = l;
385 return type;
386 }
387
388 private void
init_file_tables(void)389 init_file_tables(void)
390 {
391 static int done = 0;
392 const struct type_tbl_s *p;
393
394 if (done)
395 return;
396 done++;
397
398 for (p = type_tbl; p->len; p++) {
399 assert(p->type < FILE_NAMES_SIZE);
400 file_names[p->type] = p->name;
401 file_formats[p->type] = p->format;
402 }
403 assert(p - type_tbl == FILE_NAMES_SIZE);
404 }
405
406 private int
add_mlist(struct mlist * mlp,struct magic_map * map,size_t idx)407 add_mlist(struct mlist *mlp, struct magic_map *map, size_t idx)
408 {
409 struct mlist *ml;
410
411 mlp->map = NULL;
412 if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL)
413 return -1;
414
415 ml->map = idx == 0 ? map : NULL;
416 ml->magic = map->magic[idx];
417 ml->nmagic = map->nmagic[idx];
418
419 mlp->prev->next = ml;
420 ml->prev = mlp->prev;
421 ml->next = mlp;
422 mlp->prev = ml;
423 return 0;
424 }
425
426 /*
427 * Handle one file or directory.
428 */
429 private int
apprentice_1(struct magic_set * ms,const char * fn,int action)430 apprentice_1(struct magic_set *ms, const char *fn, int action)
431 {
432 struct magic_map *map;
433 #ifndef COMPILE_ONLY
434 struct mlist *ml;
435 size_t i;
436 #endif
437
438 if (magicsize != FILE_MAGICSIZE) {
439 file_error(ms, 0, "magic element size %lu != %lu",
440 (unsigned long)sizeof(*map->magic[0]),
441 (unsigned long)FILE_MAGICSIZE);
442 return -1;
443 }
444
445 if (action == FILE_COMPILE) {
446 map = apprentice_load(ms, fn, action);
447 if (map == NULL)
448 return -1;
449 return apprentice_compile(ms, map, fn);
450 }
451
452 #ifndef COMPILE_ONLY
453 map = apprentice_map(ms, fn);
454 if (map == (struct magic_map *)-1)
455 return -1;
456 if (map == NULL) {
457 if (ms->flags & MAGIC_CHECK)
458 file_magwarn(ms, "using regular magic file `%s'", fn);
459 map = apprentice_load(ms, fn, action);
460 if (map == NULL)
461 return -1;
462 }
463
464 for (i = 0; i < MAGIC_SETS; i++) {
465 if (add_mlist(ms->mlist[i], map, i) == -1) {
466 file_oomem(ms, sizeof(*ml));
467 return -1;
468 }
469 }
470
471 if (action == FILE_LIST) {
472 for (i = 0; i < MAGIC_SETS; i++) {
473 printf("Set %" SIZE_T_FORMAT "u:\nBinary patterns:\n",
474 i);
475 apprentice_list(ms->mlist[i], BINTEST);
476 printf("Text patterns:\n");
477 apprentice_list(ms->mlist[i], TEXTTEST);
478 }
479 }
480 return 0;
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 ms->regex_max = FILE_REGEX_MAX;
533 ms->bytes_max = FILE_BYTES_MAX;
534 return ms;
535 free:
536 free(ms);
537 return NULL;
538 }
539
540 private void
apprentice_unmap(struct magic_map * map)541 apprentice_unmap(struct magic_map *map)
542 {
543 size_t i;
544 if (map == NULL)
545 return;
546
547 switch (map->type) {
548 case MAP_TYPE_USER:
549 break;
550 case MAP_TYPE_MALLOC:
551 for (i = 0; i < MAGIC_SETS; i++) {
552 void *b = map->magic[i];
553 void *p = map->p;
554 if (CAST(char *, b) >= CAST(char *, p) &&
555 CAST(char *, b) <= CAST(char *, p) + map->len)
556 continue;
557 free(map->magic[i]);
558 }
559 free(map->p);
560 break;
561 #ifdef QUICK
562 case MAP_TYPE_MMAP:
563 if (map->p && map->p != MAP_FAILED)
564 (void)munmap(map->p, map->len);
565 break;
566 #endif
567 default:
568 abort();
569 }
570 free(map);
571 }
572
573 private struct mlist *
mlist_alloc(void)574 mlist_alloc(void)
575 {
576 struct mlist *mlist;
577 if ((mlist = CAST(struct mlist *, calloc(1, sizeof(*mlist)))) == NULL) {
578 return NULL;
579 }
580 mlist->next = mlist->prev = mlist;
581 return mlist;
582 }
583
584 private void
mlist_free(struct mlist * mlist)585 mlist_free(struct mlist *mlist)
586 {
587 struct mlist *ml, *next;
588
589 if (mlist == NULL)
590 return;
591
592 ml = mlist->next;
593 for (ml = mlist->next; (next = ml->next) != NULL; ml = next) {
594 if (ml->map)
595 apprentice_unmap(CAST(struct magic_map *, ml->map));
596 free(ml);
597 if (ml == mlist)
598 break;
599 }
600 }
601
602 #ifndef COMPILE_ONLY
603 /* void **bufs: an array of compiled magic files */
604 protected int
buffer_apprentice(struct magic_set * ms,struct magic ** bufs,size_t * sizes,size_t nbufs)605 buffer_apprentice(struct magic_set *ms, struct magic **bufs,
606 size_t *sizes, size_t nbufs)
607 {
608 size_t i, j;
609 struct mlist *ml;
610 struct magic_map *map;
611
612 if (nbufs == 0)
613 return -1;
614
615 (void)file_reset(ms, 0);
616
617 init_file_tables();
618
619 for (i = 0; i < MAGIC_SETS; i++) {
620 mlist_free(ms->mlist[i]);
621 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
622 file_oomem(ms, sizeof(*ms->mlist[i]));
623 goto fail;
624 }
625 }
626
627 for (i = 0; i < nbufs; i++) {
628 map = apprentice_buf(ms, bufs[i], sizes[i]);
629 if (map == NULL)
630 goto fail;
631
632 for (j = 0; j < MAGIC_SETS; j++) {
633 if (add_mlist(ms->mlist[j], map, j) == -1) {
634 file_oomem(ms, sizeof(*ml));
635 goto fail;
636 }
637 }
638 }
639
640 return 0;
641 fail:
642 for (i = 0; i < MAGIC_SETS; i++) {
643 mlist_free(ms->mlist[i]);
644 ms->mlist[i] = NULL;
645 }
646 return -1;
647 }
648 #endif
649
650 /* const char *fn: list of magic files and directories */
651 protected int
file_apprentice(struct magic_set * ms,const char * fn,int action)652 file_apprentice(struct magic_set *ms, const char *fn, int action)
653 {
654 char *p, *mfn;
655 int fileerr, errs = -1;
656 size_t i;
657
658 (void)file_reset(ms, 0);
659
660 if ((fn = magic_getpath(fn, action)) == NULL)
661 return -1;
662
663 init_file_tables();
664
665 if ((mfn = strdup(fn)) == NULL) {
666 file_oomem(ms, strlen(fn));
667 return -1;
668 }
669
670 for (i = 0; i < MAGIC_SETS; i++) {
671 mlist_free(ms->mlist[i]);
672 if ((ms->mlist[i] = mlist_alloc()) == NULL) {
673 file_oomem(ms, sizeof(*ms->mlist[i]));
674 while (i-- > 0) {
675 mlist_free(ms->mlist[i]);
676 ms->mlist[i] = NULL;
677 }
678 free(mfn);
679 return -1;
680 }
681 }
682 fn = mfn;
683
684 while (fn) {
685 p = strchr(fn, PATHSEP);
686 if (p)
687 *p++ = '\0';
688 if (*fn == '\0')
689 break;
690 fileerr = apprentice_1(ms, fn, action);
691 errs = MAX(errs, fileerr);
692 fn = p;
693 }
694
695 free(mfn);
696
697 if (errs == -1) {
698 for (i = 0; i < MAGIC_SETS; i++) {
699 mlist_free(ms->mlist[i]);
700 ms->mlist[i] = NULL;
701 }
702 file_error(ms, 0, "could not find any valid magic files!");
703 return -1;
704 }
705
706 #if 0
707 /*
708 * Always leave the database loaded
709 */
710 if (action == FILE_LOAD)
711 return 0;
712
713 for (i = 0; i < MAGIC_SETS; i++) {
714 mlist_free(ms->mlist[i]);
715 ms->mlist[i] = NULL;
716 }
717 #endif
718
719 switch (action) {
720 case FILE_LOAD:
721 case FILE_COMPILE:
722 case FILE_CHECK:
723 case FILE_LIST:
724 return 0;
725 default:
726 file_error(ms, 0, "Invalid action %d", action);
727 return -1;
728 }
729 }
730
731 /*
732 * Compute the real length of a magic expression, for the purposes
733 * of determining how "strong" a magic expression is (approximating
734 * how specific its matches are):
735 * - magic characters count 0 unless escaped.
736 * - [] expressions count 1
737 * - {} expressions count 0
738 * - regular characters or escaped magic characters count 1
739 * - 0 length expressions count as one
740 */
741 private size_t
nonmagic(const char * str)742 nonmagic(const char *str)
743 {
744 const char *p;
745 size_t rv = 0;
746
747 for (p = str; *p; p++)
748 switch (*p) {
749 case '\\': /* Escaped anything counts 1 */
750 if (!*++p)
751 p--;
752 rv++;
753 continue;
754 case '?': /* Magic characters count 0 */
755 case '*':
756 case '.':
757 case '+':
758 case '^':
759 case '$':
760 continue;
761 case '[': /* Bracketed expressions count 1 the ']' */
762 while (*p && *p != ']')
763 p++;
764 p--;
765 continue;
766 case '{': /* Braced expressions count 0 */
767 while (*p && *p != '}')
768 p++;
769 if (!*p)
770 p--;
771 continue;
772 default: /* Anything else counts 1 */
773 rv++;
774 continue;
775 }
776
777 return rv == 0 ? 1 : rv; /* Return at least 1 */
778 }
779
780
781 private size_t
typesize(int type)782 typesize(int type)
783 {
784 switch (type) {
785 case FILE_BYTE:
786 return 1;
787
788 case FILE_SHORT:
789 case FILE_LESHORT:
790 case FILE_BESHORT:
791 return 2;
792
793 case FILE_LONG:
794 case FILE_LELONG:
795 case FILE_BELONG:
796 case FILE_MELONG:
797 return 4;
798
799 case FILE_DATE:
800 case FILE_LEDATE:
801 case FILE_BEDATE:
802 case FILE_MEDATE:
803 case FILE_LDATE:
804 case FILE_LELDATE:
805 case FILE_BELDATE:
806 case FILE_MELDATE:
807 case FILE_FLOAT:
808 case FILE_BEFLOAT:
809 case FILE_LEFLOAT:
810 return 4;
811
812 case FILE_QUAD:
813 case FILE_BEQUAD:
814 case FILE_LEQUAD:
815 case FILE_QDATE:
816 case FILE_LEQDATE:
817 case FILE_BEQDATE:
818 case FILE_QLDATE:
819 case FILE_LEQLDATE:
820 case FILE_BEQLDATE:
821 case FILE_QWDATE:
822 case FILE_LEQWDATE:
823 case FILE_BEQWDATE:
824 case FILE_DOUBLE:
825 case FILE_BEDOUBLE:
826 case FILE_LEDOUBLE:
827 return 8;
828 default:
829 return (size_t)~0;
830 }
831 }
832
833 /*
834 * Get weight of this magic entry, for sorting purposes.
835 */
836 private size_t
apprentice_magic_strength(const struct magic * m)837 apprentice_magic_strength(const struct magic *m)
838 {
839 #define MULT 10
840 size_t ts, v, val = 2 * MULT; /* baseline strength */
841
842 switch (m->type) {
843 case FILE_DEFAULT: /* make sure this sorts last */
844 if (m->factor_op != FILE_FACTOR_OP_NONE)
845 abort();
846 return 0;
847
848 case FILE_BYTE:
849 case FILE_SHORT:
850 case FILE_LESHORT:
851 case FILE_BESHORT:
852 case FILE_LONG:
853 case FILE_LELONG:
854 case FILE_BELONG:
855 case FILE_MELONG:
856 case FILE_DATE:
857 case FILE_LEDATE:
858 case FILE_BEDATE:
859 case FILE_MEDATE:
860 case FILE_LDATE:
861 case FILE_LELDATE:
862 case FILE_BELDATE:
863 case FILE_MELDATE:
864 case FILE_FLOAT:
865 case FILE_BEFLOAT:
866 case FILE_LEFLOAT:
867 case FILE_QUAD:
868 case FILE_BEQUAD:
869 case FILE_LEQUAD:
870 case FILE_QDATE:
871 case FILE_LEQDATE:
872 case FILE_BEQDATE:
873 case FILE_QLDATE:
874 case FILE_LEQLDATE:
875 case FILE_BEQLDATE:
876 case FILE_QWDATE:
877 case FILE_LEQWDATE:
878 case FILE_BEQWDATE:
879 case FILE_DOUBLE:
880 case FILE_BEDOUBLE:
881 case FILE_LEDOUBLE:
882 ts = typesize(m->type);
883 if (ts == (size_t)~0)
884 abort();
885 val += ts * MULT;
886 break;
887
888 case FILE_PSTRING:
889 case FILE_STRING:
890 val += m->vallen * MULT;
891 break;
892
893 case FILE_BESTRING16:
894 case FILE_LESTRING16:
895 val += m->vallen * MULT / 2;
896 break;
897
898 case FILE_SEARCH:
899 val += m->vallen * MAX(MULT / m->vallen, 1);
900 break;
901
902 case FILE_REGEX:
903 v = nonmagic(m->value.s);
904 val += v * MAX(MULT / v, 1);
905 break;
906
907 case FILE_INDIRECT:
908 case FILE_NAME:
909 case FILE_USE:
910 break;
911
912 case FILE_DER:
913 val += MULT;
914 break;
915
916 default:
917 (void)fprintf(stderr, "Bad type %d\n", m->type);
918 abort();
919 }
920
921 switch (m->reln) {
922 case 'x': /* matches anything penalize */
923 case '!': /* matches almost anything penalize */
924 val = 0;
925 break;
926
927 case '=': /* Exact match, prefer */
928 val += MULT;
929 break;
930
931 case '>':
932 case '<': /* comparison match reduce strength */
933 val -= 2 * MULT;
934 break;
935
936 case '^':
937 case '&': /* masking bits, we could count them too */
938 val -= MULT;
939 break;
940
941 default:
942 (void)fprintf(stderr, "Bad relation %c\n", m->reln);
943 abort();
944 }
945
946 if (val == 0) /* ensure we only return 0 for FILE_DEFAULT */
947 val = 1;
948
949 switch (m->factor_op) {
950 case FILE_FACTOR_OP_NONE:
951 break;
952 case FILE_FACTOR_OP_PLUS:
953 val += m->factor;
954 break;
955 case FILE_FACTOR_OP_MINUS:
956 val -= m->factor;
957 break;
958 case FILE_FACTOR_OP_TIMES:
959 val *= m->factor;
960 break;
961 case FILE_FACTOR_OP_DIV:
962 val /= m->factor;
963 break;
964 default:
965 abort();
966 }
967
968 /*
969 * Magic entries with no description get a bonus because they depend
970 * on subsequent magic entries to print something.
971 */
972 if (m->desc[0] == '\0')
973 val++;
974 return val;
975 }
976
977 /*
978 * Sort callback for sorting entries by "strength" (basically length)
979 */
980 private int
apprentice_sort(const void * a,const void * b)981 apprentice_sort(const void *a, const void *b)
982 {
983 const struct magic_entry *ma = CAST(const struct magic_entry *, a);
984 const struct magic_entry *mb = CAST(const struct magic_entry *, b);
985 size_t sa = apprentice_magic_strength(ma->mp);
986 size_t sb = apprentice_magic_strength(mb->mp);
987 if (sa == sb)
988 return 0;
989 else if (sa > sb)
990 return -1;
991 else
992 return 1;
993 }
994
995 /*
996 * Shows sorted patterns list in the order which is used for the matching
997 */
998 private void
apprentice_list(struct mlist * mlist,int mode)999 apprentice_list(struct mlist *mlist, int mode)
1000 {
1001 uint32_t magindex = 0;
1002 struct mlist *ml;
1003 for (ml = mlist->next; ml != mlist; ml = ml->next) {
1004 for (magindex = 0; magindex < ml->nmagic; magindex++) {
1005 struct magic *m = &ml->magic[magindex];
1006 if ((m->flag & mode) != mode) {
1007 /* Skip sub-tests */
1008 while (magindex + 1 < ml->nmagic &&
1009 ml->magic[magindex + 1].cont_level != 0)
1010 ++magindex;
1011 continue; /* Skip to next top-level test*/
1012 }
1013
1014 /*
1015 * Try to iterate over the tree until we find item with
1016 * description/mimetype.
1017 */
1018 while (magindex + 1 < ml->nmagic &&
1019 ml->magic[magindex + 1].cont_level != 0 &&
1020 *ml->magic[magindex].desc == '\0' &&
1021 *ml->magic[magindex].mimetype == '\0')
1022 magindex++;
1023
1024 printf("Strength = %3" SIZE_T_FORMAT "u@%u: %s [%s]\n",
1025 apprentice_magic_strength(m),
1026 ml->magic[magindex].lineno,
1027 ml->magic[magindex].desc,
1028 ml->magic[magindex].mimetype);
1029 }
1030 }
1031 }
1032
1033 private void
set_test_type(struct magic * mstart,struct magic * m)1034 set_test_type(struct magic *mstart, struct magic *m)
1035 {
1036 switch (m->type) {
1037 case FILE_BYTE:
1038 case FILE_SHORT:
1039 case FILE_LONG:
1040 case FILE_DATE:
1041 case FILE_BESHORT:
1042 case FILE_BELONG:
1043 case FILE_BEDATE:
1044 case FILE_LESHORT:
1045 case FILE_LELONG:
1046 case FILE_LEDATE:
1047 case FILE_LDATE:
1048 case FILE_BELDATE:
1049 case FILE_LELDATE:
1050 case FILE_MEDATE:
1051 case FILE_MELDATE:
1052 case FILE_MELONG:
1053 case FILE_QUAD:
1054 case FILE_LEQUAD:
1055 case FILE_BEQUAD:
1056 case FILE_QDATE:
1057 case FILE_LEQDATE:
1058 case FILE_BEQDATE:
1059 case FILE_QLDATE:
1060 case FILE_LEQLDATE:
1061 case FILE_BEQLDATE:
1062 case FILE_QWDATE:
1063 case FILE_LEQWDATE:
1064 case FILE_BEQWDATE:
1065 case FILE_FLOAT:
1066 case FILE_BEFLOAT:
1067 case FILE_LEFLOAT:
1068 case FILE_DOUBLE:
1069 case FILE_BEDOUBLE:
1070 case FILE_LEDOUBLE:
1071 case FILE_DER:
1072 mstart->flag |= BINTEST;
1073 break;
1074 case FILE_STRING:
1075 case FILE_PSTRING:
1076 case FILE_BESTRING16:
1077 case FILE_LESTRING16:
1078 /* Allow text overrides */
1079 if (mstart->str_flags & STRING_TEXTTEST)
1080 mstart->flag |= TEXTTEST;
1081 else
1082 mstart->flag |= BINTEST;
1083 break;
1084 case FILE_REGEX:
1085 case FILE_SEARCH:
1086 /* Check for override */
1087 if (mstart->str_flags & STRING_BINTEST)
1088 mstart->flag |= BINTEST;
1089 if (mstart->str_flags & STRING_TEXTTEST)
1090 mstart->flag |= TEXTTEST;
1091
1092 if (mstart->flag & (TEXTTEST|BINTEST))
1093 break;
1094
1095 /* binary test if pattern is not text */
1096 if (file_looks_utf8(m->value.us, (size_t)m->vallen, NULL,
1097 NULL) <= 0)
1098 mstart->flag |= BINTEST;
1099 else
1100 mstart->flag |= TEXTTEST;
1101 break;
1102 case FILE_DEFAULT:
1103 /* can't deduce anything; we shouldn't see this at the
1104 top level anyway */
1105 break;
1106 case FILE_INVALID:
1107 default:
1108 /* invalid search type, but no need to complain here */
1109 break;
1110 }
1111 }
1112
1113 private int
addentry(struct magic_set * ms,struct magic_entry * me,struct magic_entry_set * mset)1114 addentry(struct magic_set *ms, struct magic_entry *me,
1115 struct magic_entry_set *mset)
1116 {
1117 size_t i = me->mp->type == FILE_NAME ? 1 : 0;
1118 if (mset[i].count == mset[i].max) {
1119 struct magic_entry *mp;
1120
1121 mset[i].max += ALLOC_INCR;
1122 if ((mp = CAST(struct magic_entry *,
1123 realloc(mset[i].me, sizeof(*mp) * mset[i].max))) ==
1124 NULL) {
1125 file_oomem(ms, sizeof(*mp) * mset[i].max);
1126 return -1;
1127 }
1128 (void)memset(&mp[mset[i].count], 0, sizeof(*mp) *
1129 ALLOC_INCR);
1130 mset[i].me = mp;
1131 }
1132 mset[i].me[mset[i].count++] = *me;
1133 memset(me, 0, sizeof(*me));
1134 return 0;
1135 }
1136
1137 /*
1138 * Load and parse one file.
1139 */
1140 private void
load_1(struct magic_set * ms,int action,const char * fn,int * errs,struct magic_entry_set * mset)1141 load_1(struct magic_set *ms, int action, const char *fn, int *errs,
1142 struct magic_entry_set *mset)
1143 {
1144 size_t lineno = 0, llen = 0;
1145 char *line = NULL;
1146 ssize_t len;
1147 struct magic_entry me;
1148
1149 FILE *f = fopen(ms->file = fn, "r");
1150 if (f == NULL) {
1151 if (errno != ENOENT)
1152 file_error(ms, errno, "cannot read magic file `%s'",
1153 fn);
1154 (*errs)++;
1155 return;
1156 }
1157
1158 memset(&me, 0, sizeof(me));
1159 /* read and parse this file */
1160 for (ms->line = 1; (len = getline(&line, &llen, f)) != -1;
1161 ms->line++) {
1162 if (len == 0) /* null line, garbage, etc */
1163 continue;
1164 if (line[len - 1] == '\n') {
1165 lineno++;
1166 line[len - 1] = '\0'; /* delete newline */
1167 }
1168 switch (line[0]) {
1169 case '\0': /* empty, do not parse */
1170 case '#': /* comment, do not parse */
1171 continue;
1172 case '!':
1173 if (line[1] == ':') {
1174 size_t i;
1175
1176 for (i = 0; bang[i].name != NULL; i++) {
1177 if ((size_t)(len - 2) > bang[i].len &&
1178 memcmp(bang[i].name, line + 2,
1179 bang[i].len) == 0)
1180 break;
1181 }
1182 if (bang[i].name == NULL) {
1183 file_error(ms, 0,
1184 "Unknown !: entry `%s'", line);
1185 (*errs)++;
1186 continue;
1187 }
1188 if (me.mp == NULL) {
1189 file_error(ms, 0,
1190 "No current entry for :!%s type",
1191 bang[i].name);
1192 (*errs)++;
1193 continue;
1194 }
1195 if ((*bang[i].fun)(ms, &me,
1196 line + bang[i].len + 2) != 0) {
1197 (*errs)++;
1198 continue;
1199 }
1200 continue;
1201 }
1202 /*FALLTHROUGH*/
1203 default:
1204 again:
1205 switch (parse(ms, &me, line, lineno, action)) {
1206 case 0:
1207 continue;
1208 case 1:
1209 (void)addentry(ms, &me, mset);
1210 goto again;
1211 default:
1212 (*errs)++;
1213 break;
1214 }
1215 }
1216 }
1217 if (me.mp)
1218 (void)addentry(ms, &me, mset);
1219 free(line);
1220 (void)fclose(f);
1221 }
1222
1223 /*
1224 * parse a file or directory of files
1225 * const char *fn: name of magic file or directory
1226 */
1227 private int
cmpstrp(const void * p1,const void * p2)1228 cmpstrp(const void *p1, const void *p2)
1229 {
1230 return strcmp(*(char *const *)p1, *(char *const *)p2);
1231 }
1232
1233
1234 private uint32_t
set_text_binary(struct magic_set * ms,struct magic_entry * me,uint32_t nme,uint32_t starttest)1235 set_text_binary(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1236 uint32_t starttest)
1237 {
1238 static const char text[] = "text";
1239 static const char binary[] = "binary";
1240 static const size_t len = sizeof(text);
1241
1242 uint32_t i = starttest;
1243
1244 do {
1245 set_test_type(me[starttest].mp, me[i].mp);
1246 if ((ms->flags & MAGIC_DEBUG) == 0)
1247 continue;
1248 (void)fprintf(stderr, "%s%s%s: %s\n",
1249 me[i].mp->mimetype,
1250 me[i].mp->mimetype[0] == '\0' ? "" : "; ",
1251 me[i].mp->desc[0] ? me[i].mp->desc : "(no description)",
1252 me[i].mp->flag & BINTEST ? binary : text);
1253 if (me[i].mp->flag & BINTEST) {
1254 char *p = strstr(me[i].mp->desc, text);
1255 if (p && (p == me[i].mp->desc ||
1256 isspace((unsigned char)p[-1])) &&
1257 (p + len - me[i].mp->desc == MAXstring
1258 || (p[len] == '\0' ||
1259 isspace((unsigned char)p[len]))))
1260 (void)fprintf(stderr, "*** Possible "
1261 "binary test for text type\n");
1262 }
1263 } while (++i < nme && me[i].mp->cont_level != 0);
1264 return i;
1265 }
1266
1267 private void
set_last_default(struct magic_set * ms,struct magic_entry * me,uint32_t nme)1268 set_last_default(struct magic_set *ms, struct magic_entry *me, uint32_t nme)
1269 {
1270 uint32_t i;
1271 for (i = 0; i < nme; i++) {
1272 if (me[i].mp->cont_level == 0 &&
1273 me[i].mp->type == FILE_DEFAULT) {
1274 while (++i < nme)
1275 if (me[i].mp->cont_level == 0)
1276 break;
1277 if (i != nme) {
1278 /* XXX - Ugh! */
1279 ms->line = me[i].mp->lineno;
1280 file_magwarn(ms,
1281 "level 0 \"default\" did not sort last");
1282 }
1283 return;
1284 }
1285 }
1286 }
1287
1288 private int
coalesce_entries(struct magic_set * ms,struct magic_entry * me,uint32_t nme,struct magic ** ma,uint32_t * nma)1289 coalesce_entries(struct magic_set *ms, struct magic_entry *me, uint32_t nme,
1290 struct magic **ma, uint32_t *nma)
1291 {
1292 uint32_t i, mentrycount = 0;
1293 size_t slen;
1294
1295 for (i = 0; i < nme; i++)
1296 mentrycount += me[i].cont_count;
1297
1298 slen = sizeof(**ma) * mentrycount;
1299 if ((*ma = CAST(struct magic *, malloc(slen))) == NULL) {
1300 file_oomem(ms, slen);
1301 return -1;
1302 }
1303
1304 mentrycount = 0;
1305 for (i = 0; i < nme; i++) {
1306 (void)memcpy(*ma + mentrycount, me[i].mp,
1307 me[i].cont_count * sizeof(**ma));
1308 mentrycount += me[i].cont_count;
1309 }
1310 *nma = mentrycount;
1311 return 0;
1312 }
1313
1314 private void
magic_entry_free(struct magic_entry * me,uint32_t nme)1315 magic_entry_free(struct magic_entry *me, uint32_t nme)
1316 {
1317 uint32_t i;
1318 if (me == NULL)
1319 return;
1320 for (i = 0; i < nme; i++)
1321 free(me[i].mp);
1322 free(me);
1323 }
1324
1325 private struct magic_map *
apprentice_load(struct magic_set * ms,const char * fn,int action)1326 apprentice_load(struct magic_set *ms, const char *fn, int action)
1327 {
1328 int errs = 0;
1329 uint32_t i, j;
1330 size_t files = 0, maxfiles = 0;
1331 char **filearr = NULL, *mfn;
1332 struct stat st;
1333 struct magic_map *map;
1334 struct magic_entry_set mset[MAGIC_SETS];
1335 DIR *dir;
1336 struct dirent *d;
1337
1338 memset(mset, 0, sizeof(mset));
1339 ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */
1340
1341
1342 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL)
1343 {
1344 file_oomem(ms, sizeof(*map));
1345 return NULL;
1346 }
1347 map->type = MAP_TYPE_MALLOC;
1348
1349 /* print silly verbose header for USG compat. */
1350 if (action == FILE_CHECK)
1351 (void)fprintf(stderr, "%s\n", usg_hdr);
1352
1353 /* load directory or file */
1354 if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) {
1355 dir = opendir(fn);
1356 if (!dir) {
1357 errs++;
1358 goto out;
1359 }
1360 while ((d = readdir(dir)) != NULL) {
1361 if (d->d_name[0] == '.')
1362 continue;
1363 if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) {
1364 file_oomem(ms,
1365 strlen(fn) + strlen(d->d_name) + 2);
1366 errs++;
1367 closedir(dir);
1368 goto out;
1369 }
1370 if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) {
1371 free(mfn);
1372 continue;
1373 }
1374 if (files >= maxfiles) {
1375 size_t mlen;
1376 maxfiles = (maxfiles + 1) * 2;
1377 mlen = maxfiles * sizeof(*filearr);
1378 if ((filearr = CAST(char **,
1379 realloc(filearr, mlen))) == NULL) {
1380 file_oomem(ms, mlen);
1381 free(mfn);
1382 closedir(dir);
1383 errs++;
1384 goto out;
1385 }
1386 }
1387 filearr[files++] = mfn;
1388 }
1389 closedir(dir);
1390 qsort(filearr, files, sizeof(*filearr), cmpstrp);
1391 for (i = 0; i < files; i++) {
1392 load_1(ms, action, filearr[i], &errs, mset);
1393 free(filearr[i]);
1394 }
1395 free(filearr);
1396 } else
1397 load_1(ms, action, fn, &errs, mset);
1398 if (errs)
1399 goto out;
1400
1401 for (j = 0; j < MAGIC_SETS; j++) {
1402 /* Set types of tests */
1403 for (i = 0; i < mset[j].count; ) {
1404 if (mset[j].me[i].mp->cont_level != 0) {
1405 i++;
1406 continue;
1407 }
1408 i = set_text_binary(ms, mset[j].me, mset[j].count, i);
1409 }
1410 if (mset[j].me)
1411 qsort(mset[j].me, mset[j].count, sizeof(*mset[j].me),
1412 apprentice_sort);
1413
1414 /*
1415 * Make sure that any level 0 "default" line is last
1416 * (if one exists).
1417 */
1418 set_last_default(ms, mset[j].me, mset[j].count);
1419
1420 /* coalesce per file arrays into a single one */
1421 if (coalesce_entries(ms, mset[j].me, mset[j].count,
1422 &map->magic[j], &map->nmagic[j]) == -1) {
1423 errs++;
1424 goto out;
1425 }
1426 }
1427
1428 out:
1429 for (j = 0; j < MAGIC_SETS; j++)
1430 magic_entry_free(mset[j].me, mset[j].count);
1431
1432 if (errs) {
1433 apprentice_unmap(map);
1434 return NULL;
1435 }
1436 return map;
1437 }
1438
1439 /*
1440 * extend the sign bit if the comparison is to be signed
1441 */
1442 protected uint64_t
file_signextend(struct magic_set * ms,struct magic * m,uint64_t v)1443 file_signextend(struct magic_set *ms, struct magic *m, uint64_t v)
1444 {
1445 if (!(m->flag & UNSIGNED)) {
1446 switch(m->type) {
1447 /*
1448 * Do not remove the casts below. They are
1449 * vital. When later compared with the data,
1450 * the sign extension must have happened.
1451 */
1452 case FILE_BYTE:
1453 v = (signed char) v;
1454 break;
1455 case FILE_SHORT:
1456 case FILE_BESHORT:
1457 case FILE_LESHORT:
1458 v = (short) v;
1459 break;
1460 case FILE_DATE:
1461 case FILE_BEDATE:
1462 case FILE_LEDATE:
1463 case FILE_MEDATE:
1464 case FILE_LDATE:
1465 case FILE_BELDATE:
1466 case FILE_LELDATE:
1467 case FILE_MELDATE:
1468 case FILE_LONG:
1469 case FILE_BELONG:
1470 case FILE_LELONG:
1471 case FILE_MELONG:
1472 case FILE_FLOAT:
1473 case FILE_BEFLOAT:
1474 case FILE_LEFLOAT:
1475 v = (int32_t) v;
1476 break;
1477 case FILE_QUAD:
1478 case FILE_BEQUAD:
1479 case FILE_LEQUAD:
1480 case FILE_QDATE:
1481 case FILE_QLDATE:
1482 case FILE_QWDATE:
1483 case FILE_BEQDATE:
1484 case FILE_BEQLDATE:
1485 case FILE_BEQWDATE:
1486 case FILE_LEQDATE:
1487 case FILE_LEQLDATE:
1488 case FILE_LEQWDATE:
1489 case FILE_DOUBLE:
1490 case FILE_BEDOUBLE:
1491 case FILE_LEDOUBLE:
1492 v = (int64_t) v;
1493 break;
1494 case FILE_STRING:
1495 case FILE_PSTRING:
1496 case FILE_BESTRING16:
1497 case FILE_LESTRING16:
1498 case FILE_REGEX:
1499 case FILE_SEARCH:
1500 case FILE_DEFAULT:
1501 case FILE_INDIRECT:
1502 case FILE_NAME:
1503 case FILE_USE:
1504 case FILE_CLEAR:
1505 case FILE_DER:
1506 break;
1507 default:
1508 if (ms->flags & MAGIC_CHECK)
1509 file_magwarn(ms, "cannot happen: m->type=%d\n",
1510 m->type);
1511 return ~0U;
1512 }
1513 }
1514 return v;
1515 }
1516
1517 private int
string_modifier_check(struct magic_set * ms,struct magic * m)1518 string_modifier_check(struct magic_set *ms, struct magic *m)
1519 {
1520 if ((ms->flags & MAGIC_CHECK) == 0)
1521 return 0;
1522
1523 if ((m->type != FILE_REGEX || (m->str_flags & REGEX_LINE_COUNT) == 0) &&
1524 (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0)) {
1525 file_magwarn(ms,
1526 "'/BHhLl' modifiers are only allowed for pascal strings\n");
1527 return -1;
1528 }
1529 switch (m->type) {
1530 case FILE_BESTRING16:
1531 case FILE_LESTRING16:
1532 if (m->str_flags != 0) {
1533 file_magwarn(ms,
1534 "no modifiers allowed for 16-bit strings\n");
1535 return -1;
1536 }
1537 break;
1538 case FILE_STRING:
1539 case FILE_PSTRING:
1540 if ((m->str_flags & REGEX_OFFSET_START) != 0) {
1541 file_magwarn(ms,
1542 "'/%c' only allowed on regex and search\n",
1543 CHAR_REGEX_OFFSET_START);
1544 return -1;
1545 }
1546 break;
1547 case FILE_SEARCH:
1548 if (m->str_range == 0) {
1549 file_magwarn(ms,
1550 "missing range; defaulting to %d\n",
1551 STRING_DEFAULT_RANGE);
1552 m->str_range = STRING_DEFAULT_RANGE;
1553 return -1;
1554 }
1555 break;
1556 case FILE_REGEX:
1557 if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) {
1558 file_magwarn(ms, "'/%c' not allowed on regex\n",
1559 CHAR_COMPACT_WHITESPACE);
1560 return -1;
1561 }
1562 if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) {
1563 file_magwarn(ms, "'/%c' not allowed on regex\n",
1564 CHAR_COMPACT_OPTIONAL_WHITESPACE);
1565 return -1;
1566 }
1567 break;
1568 default:
1569 file_magwarn(ms, "coding error: m->type=%d\n",
1570 m->type);
1571 return -1;
1572 }
1573 return 0;
1574 }
1575
1576 private int
get_op(char c)1577 get_op(char c)
1578 {
1579 switch (c) {
1580 case '&':
1581 return FILE_OPAND;
1582 case '|':
1583 return FILE_OPOR;
1584 case '^':
1585 return FILE_OPXOR;
1586 case '+':
1587 return FILE_OPADD;
1588 case '-':
1589 return FILE_OPMINUS;
1590 case '*':
1591 return FILE_OPMULTIPLY;
1592 case '/':
1593 return FILE_OPDIVIDE;
1594 case '%':
1595 return FILE_OPMODULO;
1596 default:
1597 return -1;
1598 }
1599 }
1600
1601 #ifdef ENABLE_CONDITIONALS
1602 private int
get_cond(const char * l,const char ** t)1603 get_cond(const char *l, const char **t)
1604 {
1605 static const struct cond_tbl_s {
1606 char name[8];
1607 size_t len;
1608 int cond;
1609 } cond_tbl[] = {
1610 { "if", 2, COND_IF },
1611 { "elif", 4, COND_ELIF },
1612 { "else", 4, COND_ELSE },
1613 { "", 0, COND_NONE },
1614 };
1615 const struct cond_tbl_s *p;
1616
1617 for (p = cond_tbl; p->len; p++) {
1618 if (strncmp(l, p->name, p->len) == 0 &&
1619 isspace((unsigned char)l[p->len])) {
1620 if (t)
1621 *t = l + p->len;
1622 break;
1623 }
1624 }
1625 return p->cond;
1626 }
1627
1628 private int
check_cond(struct magic_set * ms,int cond,uint32_t cont_level)1629 check_cond(struct magic_set *ms, int cond, uint32_t cont_level)
1630 {
1631 int last_cond;
1632 last_cond = ms->c.li[cont_level].last_cond;
1633
1634 switch (cond) {
1635 case COND_IF:
1636 if (last_cond != COND_NONE && last_cond != COND_ELIF) {
1637 if (ms->flags & MAGIC_CHECK)
1638 file_magwarn(ms, "syntax error: `if'");
1639 return -1;
1640 }
1641 last_cond = COND_IF;
1642 break;
1643
1644 case COND_ELIF:
1645 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1646 if (ms->flags & MAGIC_CHECK)
1647 file_magwarn(ms, "syntax error: `elif'");
1648 return -1;
1649 }
1650 last_cond = COND_ELIF;
1651 break;
1652
1653 case COND_ELSE:
1654 if (last_cond != COND_IF && last_cond != COND_ELIF) {
1655 if (ms->flags & MAGIC_CHECK)
1656 file_magwarn(ms, "syntax error: `else'");
1657 return -1;
1658 }
1659 last_cond = COND_NONE;
1660 break;
1661
1662 case COND_NONE:
1663 last_cond = COND_NONE;
1664 break;
1665 }
1666
1667 ms->c.li[cont_level].last_cond = last_cond;
1668 return 0;
1669 }
1670 #endif /* ENABLE_CONDITIONALS */
1671
1672 private int
parse_indirect_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1673 parse_indirect_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1674 {
1675 const char *l = *lp;
1676
1677 while (!isspace((unsigned char)*++l))
1678 switch (*l) {
1679 case CHAR_INDIRECT_RELATIVE:
1680 m->str_flags |= INDIRECT_RELATIVE;
1681 break;
1682 default:
1683 if (ms->flags & MAGIC_CHECK)
1684 file_magwarn(ms, "indirect modifier `%c' "
1685 "invalid", *l);
1686 *lp = l;
1687 return -1;
1688 }
1689 *lp = l;
1690 return 0;
1691 }
1692
1693 private void
parse_op_modifier(struct magic_set * ms,struct magic * m,const char ** lp,int op)1694 parse_op_modifier(struct magic_set *ms, struct magic *m, const char **lp,
1695 int op)
1696 {
1697 const char *l = *lp;
1698 char *t;
1699 uint64_t val;
1700
1701 ++l;
1702 m->mask_op |= op;
1703 val = (uint64_t)strtoull(l, &t, 0);
1704 l = t;
1705 m->num_mask = file_signextend(ms, m, val);
1706 eatsize(&l);
1707 *lp = l;
1708 }
1709
1710 private int
parse_string_modifier(struct magic_set * ms,struct magic * m,const char ** lp)1711 parse_string_modifier(struct magic_set *ms, struct magic *m, const char **lp)
1712 {
1713 const char *l = *lp;
1714 char *t;
1715 int have_range = 0;
1716
1717 while (!isspace((unsigned char)*++l)) {
1718 switch (*l) {
1719 case '0': case '1': case '2':
1720 case '3': case '4': case '5':
1721 case '6': case '7': case '8':
1722 case '9':
1723 if (have_range && (ms->flags & MAGIC_CHECK))
1724 file_magwarn(ms, "multiple ranges");
1725 have_range = 1;
1726 m->str_range = CAST(uint32_t, strtoul(l, &t, 0));
1727 if (m->str_range == 0)
1728 file_magwarn(ms, "zero range");
1729 l = t - 1;
1730 break;
1731 case CHAR_COMPACT_WHITESPACE:
1732 m->str_flags |= STRING_COMPACT_WHITESPACE;
1733 break;
1734 case CHAR_COMPACT_OPTIONAL_WHITESPACE:
1735 m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE;
1736 break;
1737 case CHAR_IGNORE_LOWERCASE:
1738 m->str_flags |= STRING_IGNORE_LOWERCASE;
1739 break;
1740 case CHAR_IGNORE_UPPERCASE:
1741 m->str_flags |= STRING_IGNORE_UPPERCASE;
1742 break;
1743 case CHAR_REGEX_OFFSET_START:
1744 m->str_flags |= REGEX_OFFSET_START;
1745 break;
1746 case CHAR_BINTEST:
1747 m->str_flags |= STRING_BINTEST;
1748 break;
1749 case CHAR_TEXTTEST:
1750 m->str_flags |= STRING_TEXTTEST;
1751 break;
1752 case CHAR_TRIM:
1753 m->str_flags |= STRING_TRIM;
1754 break;
1755 case CHAR_PSTRING_1_LE:
1756 #define SET_LENGTH(a) m->str_flags = (m->str_flags & ~PSTRING_LEN) | (a)
1757 if (m->type != FILE_PSTRING)
1758 goto bad;
1759 SET_LENGTH(PSTRING_1_LE);
1760 break;
1761 case CHAR_PSTRING_2_BE:
1762 if (m->type != FILE_PSTRING)
1763 goto bad;
1764 SET_LENGTH(PSTRING_2_BE);
1765 break;
1766 case CHAR_PSTRING_2_LE:
1767 if (m->type != FILE_PSTRING)
1768 goto bad;
1769 SET_LENGTH(PSTRING_2_LE);
1770 break;
1771 case CHAR_PSTRING_4_BE:
1772 if (m->type != FILE_PSTRING)
1773 goto bad;
1774 SET_LENGTH(PSTRING_4_BE);
1775 break;
1776 case CHAR_PSTRING_4_LE:
1777 switch (m->type) {
1778 case FILE_PSTRING:
1779 case FILE_REGEX:
1780 break;
1781 default:
1782 goto bad;
1783 }
1784 SET_LENGTH(PSTRING_4_LE);
1785 break;
1786 case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF:
1787 if (m->type != FILE_PSTRING)
1788 goto bad;
1789 m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF;
1790 break;
1791 default:
1792 bad:
1793 if (ms->flags & MAGIC_CHECK)
1794 file_magwarn(ms, "string modifier `%c' "
1795 "invalid", *l);
1796 goto out;
1797 }
1798 /* allow multiple '/' for readability */
1799 if (l[1] == '/' && !isspace((unsigned char)l[2]))
1800 l++;
1801 }
1802 if (string_modifier_check(ms, m) == -1)
1803 goto out;
1804 *lp = l;
1805 return 0;
1806 out:
1807 *lp = l;
1808 return -1;
1809 }
1810
1811 /*
1812 * parse one line from magic file, put into magic[index++] if valid
1813 */
1814 private int
parse(struct magic_set * ms,struct magic_entry * me,const char * line,size_t lineno,int action)1815 parse(struct magic_set *ms, struct magic_entry *me, const char *line,
1816 size_t lineno, int action)
1817 {
1818 #ifdef ENABLE_CONDITIONALS
1819 static uint32_t last_cont_level = 0;
1820 #endif
1821 size_t i;
1822 struct magic *m;
1823 const char *l = line;
1824 char *t;
1825 int op;
1826 uint32_t cont_level;
1827 int32_t diff;
1828
1829 cont_level = 0;
1830
1831 /*
1832 * Parse the offset.
1833 */
1834 while (*l == '>') {
1835 ++l; /* step over */
1836 cont_level++;
1837 }
1838 #ifdef ENABLE_CONDITIONALS
1839 if (cont_level == 0 || cont_level > last_cont_level)
1840 if (file_check_mem(ms, cont_level) == -1)
1841 return -1;
1842 last_cont_level = cont_level;
1843 #endif
1844 if (cont_level != 0) {
1845 if (me->mp == NULL) {
1846 file_magerror(ms, "No current entry for continuation");
1847 return -1;
1848 }
1849 if (me->cont_count == 0) {
1850 file_magerror(ms, "Continuations present with 0 count");
1851 return -1;
1852 }
1853 m = &me->mp[me->cont_count - 1];
1854 diff = (int32_t)cont_level - (int32_t)m->cont_level;
1855 if (diff > 1)
1856 file_magwarn(ms, "New continuation level %u is more "
1857 "than one larger than current level %u", cont_level,
1858 m->cont_level);
1859 if (me->cont_count == me->max_count) {
1860 struct magic *nm;
1861 size_t cnt = me->max_count + ALLOC_CHUNK;
1862 if ((nm = CAST(struct magic *, realloc(me->mp,
1863 sizeof(*nm) * cnt))) == NULL) {
1864 file_oomem(ms, sizeof(*nm) * cnt);
1865 return -1;
1866 }
1867 me->mp = m = nm;
1868 me->max_count = CAST(uint32_t, cnt);
1869 }
1870 m = &me->mp[me->cont_count++];
1871 (void)memset(m, 0, sizeof(*m));
1872 m->cont_level = cont_level;
1873 } else {
1874 static const size_t len = sizeof(*m) * ALLOC_CHUNK;
1875 if (me->mp != NULL)
1876 return 1;
1877 if ((m = CAST(struct magic *, malloc(len))) == NULL) {
1878 file_oomem(ms, len);
1879 return -1;
1880 }
1881 me->mp = m;
1882 me->max_count = ALLOC_CHUNK;
1883 (void)memset(m, 0, sizeof(*m));
1884 m->factor_op = FILE_FACTOR_OP_NONE;
1885 m->cont_level = 0;
1886 me->cont_count = 1;
1887 }
1888 m->lineno = CAST(uint32_t, lineno);
1889
1890 if (*l == '&') { /* m->cont_level == 0 checked below. */
1891 ++l; /* step over */
1892 m->flag |= OFFADD;
1893 }
1894 if (*l == '(') {
1895 ++l; /* step over */
1896 m->flag |= INDIR;
1897 if (m->flag & OFFADD)
1898 m->flag = (m->flag & ~OFFADD) | INDIROFFADD;
1899
1900 if (*l == '&') { /* m->cont_level == 0 checked below */
1901 ++l; /* step over */
1902 m->flag |= OFFADD;
1903 }
1904 }
1905 /* Indirect offsets are not valid at level 0. */
1906 if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) {
1907 if (ms->flags & MAGIC_CHECK)
1908 file_magwarn(ms, "relative offset at level 0");
1909 return -1;
1910 }
1911
1912 /* get offset, then skip over it */
1913 m->offset = (int32_t)strtol(l, &t, 0);
1914 if (l == t) {
1915 if (ms->flags & MAGIC_CHECK)
1916 file_magwarn(ms, "offset `%s' invalid", l);
1917 return -1;
1918 }
1919 #if 0
1920 if (m->offset < 0 && cont_level != 0 &&
1921 (m->flag & (OFFADD | INDIROFFADD)) == 0) {
1922 if (ms->flags & MAGIC_CHECK) {
1923 file_magwarn(ms,
1924 "negative direct offset `%s' at level %u",
1925 l, cont_level);
1926 }
1927 return -1;
1928 }
1929 #endif
1930 l = t;
1931
1932 if (m->flag & INDIR) {
1933 m->in_type = FILE_LONG;
1934 m->in_offset = 0;
1935 m->in_op = 0;
1936 /*
1937 * read [.,lbs][+-]nnnnn)
1938 */
1939 if (*l == '.' || *l == ',') {
1940 if (*l == ',')
1941 m->in_op |= FILE_OPSIGNED;
1942 l++;
1943 switch (*l) {
1944 case 'l':
1945 m->in_type = FILE_LELONG;
1946 break;
1947 case 'L':
1948 m->in_type = FILE_BELONG;
1949 break;
1950 case 'm':
1951 m->in_type = FILE_MELONG;
1952 break;
1953 case 'h':
1954 case 's':
1955 m->in_type = FILE_LESHORT;
1956 break;
1957 case 'H':
1958 case 'S':
1959 m->in_type = FILE_BESHORT;
1960 break;
1961 case 'c':
1962 case 'b':
1963 case 'C':
1964 case 'B':
1965 m->in_type = FILE_BYTE;
1966 break;
1967 case 'e':
1968 case 'f':
1969 case 'g':
1970 m->in_type = FILE_LEDOUBLE;
1971 break;
1972 case 'E':
1973 case 'F':
1974 case 'G':
1975 m->in_type = FILE_BEDOUBLE;
1976 break;
1977 case 'i':
1978 m->in_type = FILE_LEID3;
1979 break;
1980 case 'I':
1981 m->in_type = FILE_BEID3;
1982 break;
1983 case 'q':
1984 m->in_type = FILE_LEQUAD;
1985 break;
1986 case 'Q':
1987 m->in_type = FILE_BEQUAD;
1988 break;
1989 default:
1990 if (ms->flags & MAGIC_CHECK)
1991 file_magwarn(ms,
1992 "indirect offset type `%c' invalid",
1993 *l);
1994 return -1;
1995 }
1996 l++;
1997 }
1998
1999 if (*l == '~') {
2000 m->in_op |= FILE_OPINVERSE;
2001 l++;
2002 }
2003 if ((op = get_op(*l)) != -1) {
2004 m->in_op |= op;
2005 l++;
2006 }
2007 if (*l == '(') {
2008 m->in_op |= FILE_OPINDIRECT;
2009 l++;
2010 }
2011 if (isdigit((unsigned char)*l) || *l == '-') {
2012 m->in_offset = (int32_t)strtol(l, &t, 0);
2013 if (l == t) {
2014 if (ms->flags & MAGIC_CHECK)
2015 file_magwarn(ms,
2016 "in_offset `%s' invalid", l);
2017 return -1;
2018 }
2019 l = t;
2020 }
2021 if (*l++ != ')' ||
2022 ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) {
2023 if (ms->flags & MAGIC_CHECK)
2024 file_magwarn(ms,
2025 "missing ')' in indirect offset");
2026 return -1;
2027 }
2028 }
2029 EATAB;
2030
2031 #ifdef ENABLE_CONDITIONALS
2032 m->cond = get_cond(l, &l);
2033 if (check_cond(ms, m->cond, cont_level) == -1)
2034 return -1;
2035
2036 EATAB;
2037 #endif
2038
2039 /*
2040 * Parse the type.
2041 */
2042 if (*l == 'u') {
2043 /*
2044 * Try it as a keyword type prefixed by "u"; match what
2045 * follows the "u". If that fails, try it as an SUS
2046 * integer type.
2047 */
2048 m->type = get_type(type_tbl, l + 1, &l);
2049 if (m->type == FILE_INVALID) {
2050 /*
2051 * Not a keyword type; parse it as an SUS type,
2052 * 'u' possibly followed by a number or C/S/L.
2053 */
2054 m->type = get_standard_integer_type(l, &l);
2055 }
2056 /* It's unsigned. */
2057 if (m->type != FILE_INVALID)
2058 m->flag |= UNSIGNED;
2059 } else {
2060 /*
2061 * Try it as a keyword type. If that fails, try it as
2062 * an SUS integer type if it begins with "d" or as an
2063 * SUS string type if it begins with "s". In any case,
2064 * it's not unsigned.
2065 */
2066 m->type = get_type(type_tbl, l, &l);
2067 if (m->type == FILE_INVALID) {
2068 /*
2069 * Not a keyword type; parse it as an SUS type,
2070 * either 'd' possibly followed by a number or
2071 * C/S/L, or just 's'.
2072 */
2073 if (*l == 'd')
2074 m->type = get_standard_integer_type(l, &l);
2075 else if (*l == 's' && !isalpha((unsigned char)l[1])) {
2076 m->type = FILE_STRING;
2077 ++l;
2078 }
2079 }
2080 }
2081
2082 if (m->type == FILE_INVALID) {
2083 /* Not found - try it as a special keyword. */
2084 m->type = get_type(special_tbl, l, &l);
2085 }
2086
2087 if (m->type == FILE_INVALID) {
2088 if (ms->flags & MAGIC_CHECK)
2089 file_magwarn(ms, "type `%s' invalid", l);
2090 return -1;
2091 }
2092
2093 /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */
2094 /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */
2095
2096 m->mask_op = 0;
2097 if (*l == '~') {
2098 if (!IS_STRING(m->type))
2099 m->mask_op |= FILE_OPINVERSE;
2100 else if (ms->flags & MAGIC_CHECK)
2101 file_magwarn(ms, "'~' invalid for string types");
2102 ++l;
2103 }
2104 m->str_range = 0;
2105 m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0;
2106 if ((op = get_op(*l)) != -1) {
2107 if (IS_STRING(m->type)) {
2108 int r;
2109
2110 if (op != FILE_OPDIVIDE) {
2111 if (ms->flags & MAGIC_CHECK)
2112 file_magwarn(ms,
2113 "invalid string/indirect op: "
2114 "`%c'", *t);
2115 return -1;
2116 }
2117
2118 if (m->type == FILE_INDIRECT)
2119 r = parse_indirect_modifier(ms, m, &l);
2120 else
2121 r = parse_string_modifier(ms, m, &l);
2122 if (r == -1)
2123 return -1;
2124 } else
2125 parse_op_modifier(ms, m, &l, op);
2126 }
2127
2128 /*
2129 * We used to set mask to all 1's here, instead let's just not do
2130 * anything if mask = 0 (unless you have a better idea)
2131 */
2132 EATAB;
2133
2134 switch (*l) {
2135 case '>':
2136 case '<':
2137 m->reln = *l;
2138 ++l;
2139 if (*l == '=') {
2140 if (ms->flags & MAGIC_CHECK) {
2141 file_magwarn(ms, "%c= not supported",
2142 m->reln);
2143 return -1;
2144 }
2145 ++l;
2146 }
2147 break;
2148 /* Old-style anding: "0 byte &0x80 dynamically linked" */
2149 case '&':
2150 case '^':
2151 case '=':
2152 m->reln = *l;
2153 ++l;
2154 if (*l == '=') {
2155 /* HP compat: ignore &= etc. */
2156 ++l;
2157 }
2158 break;
2159 case '!':
2160 m->reln = *l;
2161 ++l;
2162 break;
2163 default:
2164 m->reln = '='; /* the default relation */
2165 if (*l == 'x' && ((isascii((unsigned char)l[1]) &&
2166 isspace((unsigned char)l[1])) || !l[1])) {
2167 m->reln = *l;
2168 ++l;
2169 }
2170 break;
2171 }
2172 /*
2173 * Grab the value part, except for an 'x' reln.
2174 */
2175 if (m->reln != 'x' && getvalue(ms, m, &l, action))
2176 return -1;
2177
2178 /*
2179 * TODO finish this macro and start using it!
2180 * #define offsetcheck {if (offset > ms->bytes_max -1)
2181 * magwarn("offset too big"); }
2182 */
2183
2184 /*
2185 * Now get last part - the description
2186 */
2187 EATAB;
2188 if (l[0] == '\b') {
2189 ++l;
2190 m->flag |= NOSPACE;
2191 } else if ((l[0] == '\\') && (l[1] == 'b')) {
2192 ++l;
2193 ++l;
2194 m->flag |= NOSPACE;
2195 }
2196 for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); )
2197 continue;
2198 if (i == sizeof(m->desc)) {
2199 m->desc[sizeof(m->desc) - 1] = '\0';
2200 if (ms->flags & MAGIC_CHECK)
2201 file_magwarn(ms, "description `%s' truncated", m->desc);
2202 }
2203
2204 /*
2205 * We only do this check while compiling, or if any of the magic
2206 * files were not compiled.
2207 */
2208 if (ms->flags & MAGIC_CHECK) {
2209 if (check_format(ms, m) == -1)
2210 return -1;
2211 }
2212 #ifndef COMPILE_ONLY
2213 if (action == FILE_CHECK) {
2214 file_mdump(m);
2215 }
2216 #endif
2217 m->mimetype[0] = '\0'; /* initialise MIME type to none */
2218 return 0;
2219 }
2220
2221 /*
2222 * parse a STRENGTH annotation line from magic file, put into magic[index - 1]
2223 * if valid
2224 */
2225 private int
parse_strength(struct magic_set * ms,struct magic_entry * me,const char * line)2226 parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line)
2227 {
2228 const char *l = line;
2229 char *el;
2230 unsigned long factor;
2231 struct magic *m = &me->mp[0];
2232
2233 if (m->factor_op != FILE_FACTOR_OP_NONE) {
2234 file_magwarn(ms,
2235 "Current entry already has a strength type: %c %d",
2236 m->factor_op, m->factor);
2237 return -1;
2238 }
2239 if (m->type == FILE_NAME) {
2240 file_magwarn(ms, "%s: Strength setting is not supported in "
2241 "\"name\" magic entries", m->value.s);
2242 return -1;
2243 }
2244 EATAB;
2245 switch (*l) {
2246 case FILE_FACTOR_OP_NONE:
2247 case FILE_FACTOR_OP_PLUS:
2248 case FILE_FACTOR_OP_MINUS:
2249 case FILE_FACTOR_OP_TIMES:
2250 case FILE_FACTOR_OP_DIV:
2251 m->factor_op = *l++;
2252 break;
2253 default:
2254 file_magwarn(ms, "Unknown factor op `%c'", *l);
2255 return -1;
2256 }
2257 EATAB;
2258 factor = strtoul(l, &el, 0);
2259 if (factor > 255) {
2260 file_magwarn(ms, "Too large factor `%lu'", factor);
2261 goto out;
2262 }
2263 if (*el && !isspace((unsigned char)*el)) {
2264 file_magwarn(ms, "Bad factor `%s'", l);
2265 goto out;
2266 }
2267 m->factor = (uint8_t)factor;
2268 if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) {
2269 file_magwarn(ms, "Cannot have factor op `%c' and factor %u",
2270 m->factor_op, m->factor);
2271 goto out;
2272 }
2273 return 0;
2274 out:
2275 m->factor_op = FILE_FACTOR_OP_NONE;
2276 m->factor = 0;
2277 return -1;
2278 }
2279
2280 private int
goodchar(unsigned char x,const char * extra)2281 goodchar(unsigned char x, const char *extra)
2282 {
2283 return (isascii(x) && isalnum(x)) || strchr(extra, x);
2284 }
2285
2286 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)2287 parse_extra(struct magic_set *ms, struct magic_entry *me, const char *line,
2288 off_t off, size_t len, const char *name, const char *extra, int nt)
2289 {
2290 size_t i;
2291 const char *l = line;
2292 struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1];
2293 char *buf = CAST(char *, CAST(void *, m)) + off;
2294
2295 if (buf[0] != '\0') {
2296 len = nt ? strlen(buf) : len;
2297 file_magwarn(ms, "Current entry already has a %s type "
2298 "`%.*s', new type `%s'", name, (int)len, buf, l);
2299 return -1;
2300 }
2301
2302 if (*m->desc == '\0') {
2303 file_magwarn(ms, "Current entry does not yet have a "
2304 "description for adding a %s type", name);
2305 return -1;
2306 }
2307
2308 EATAB;
2309 for (i = 0; *l && i < len && goodchar(*l, extra); buf[i++] = *l++)
2310 continue;
2311
2312 if (i == len && *l) {
2313 if (nt)
2314 buf[len - 1] = '\0';
2315 if (ms->flags & MAGIC_CHECK)
2316 file_magwarn(ms, "%s type `%s' truncated %"
2317 SIZE_T_FORMAT "u", name, line, i);
2318 } else {
2319 if (!isspace((unsigned char)*l) && !goodchar(*l, extra))
2320 file_magwarn(ms, "%s type `%s' has bad char '%c'",
2321 name, line, *l);
2322 if (nt)
2323 buf[i] = '\0';
2324 }
2325
2326 if (i > 0)
2327 return 0;
2328
2329 file_magerror(ms, "Bad magic entry '%s'", line);
2330 return -1;
2331 }
2332
2333 /*
2334 * Parse an Apple CREATOR/TYPE annotation from magic file and put it into
2335 * magic[index - 1]
2336 */
2337 private int
parse_apple(struct magic_set * ms,struct magic_entry * me,const char * line)2338 parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line)
2339 {
2340 struct magic *m = &me->mp[0];
2341
2342 return parse_extra(ms, me, line,
2343 CAST(off_t, offsetof(struct magic, apple)),
2344 sizeof(m->apple), "APPLE", "!+-./?", 0);
2345 }
2346
2347 /*
2348 * Parse a comma-separated list of extensions
2349 */
2350 private int
parse_ext(struct magic_set * ms,struct magic_entry * me,const char * line)2351 parse_ext(struct magic_set *ms, struct magic_entry *me, const char *line)
2352 {
2353 struct magic *m = &me->mp[0];
2354
2355 return parse_extra(ms, me, line,
2356 CAST(off_t, offsetof(struct magic, ext)),
2357 sizeof(m->ext), "EXTENSION", ",!+-/@?_$", 0);
2358 }
2359
2360 /*
2361 * parse a MIME annotation line from magic file, put into magic[index - 1]
2362 * if valid
2363 */
2364 private int
parse_mime(struct magic_set * ms,struct magic_entry * me,const char * line)2365 parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line)
2366 {
2367 struct magic *m = &me->mp[0];
2368
2369 return parse_extra(ms, me, line,
2370 CAST(off_t, offsetof(struct magic, mimetype)),
2371 sizeof(m->mimetype), "MIME", "+-/.$?:{}", 1);
2372 }
2373
2374 private int
check_format_type(const char * ptr,int type,const char ** estr)2375 check_format_type(const char *ptr, int type, const char **estr)
2376 {
2377 int quad = 0, h;
2378 size_t len, cnt;
2379 if (*ptr == '\0') {
2380 /* Missing format string; bad */
2381 *estr = "missing format spec";
2382 return -1;
2383 }
2384
2385 switch (file_formats[type]) {
2386 case FILE_FMT_QUAD:
2387 quad = 1;
2388 /*FALLTHROUGH*/
2389 case FILE_FMT_NUM:
2390 if (quad == 0) {
2391 switch (type) {
2392 case FILE_BYTE:
2393 h = 2;
2394 break;
2395 case FILE_SHORT:
2396 case FILE_BESHORT:
2397 case FILE_LESHORT:
2398 h = 1;
2399 break;
2400 case FILE_LONG:
2401 case FILE_BELONG:
2402 case FILE_LELONG:
2403 case FILE_MELONG:
2404 case FILE_LEID3:
2405 case FILE_BEID3:
2406 case FILE_INDIRECT:
2407 h = 0;
2408 break;
2409 default:
2410 abort();
2411 }
2412 } else
2413 h = 0;
2414 if (*ptr == '-')
2415 ptr++;
2416 if (*ptr == '.')
2417 ptr++;
2418 if (*ptr == '#')
2419 ptr++;
2420 #define CHECKLEN() do { \
2421 for (len = cnt = 0; isdigit((unsigned char)*ptr); ptr++, cnt++) \
2422 len = len * 10 + (*ptr - '0'); \
2423 if (cnt > 5 || len > 1024) \
2424 goto toolong; \
2425 } while (/*CONSTCOND*/0)
2426
2427 CHECKLEN();
2428 if (*ptr == '.')
2429 ptr++;
2430 CHECKLEN();
2431 if (quad) {
2432 if (*ptr++ != 'l')
2433 goto invalid;
2434 if (*ptr++ != 'l')
2435 goto invalid;
2436 }
2437
2438 switch (*ptr++) {
2439 #ifdef STRICT_FORMAT /* "long" formats are int formats for us */
2440 /* so don't accept the 'l' modifier */
2441 case 'l':
2442 switch (*ptr++) {
2443 case 'i':
2444 case 'd':
2445 case 'u':
2446 case 'o':
2447 case 'x':
2448 case 'X':
2449 if (h == 0)
2450 return 0;
2451 /*FALLTHROUGH*/
2452 default:
2453 goto invalid;
2454 }
2455
2456 /*
2457 * Don't accept h and hh modifiers. They make writing
2458 * magic entries more complicated, for very little benefit
2459 */
2460 case 'h':
2461 if (h-- <= 0)
2462 goto invalid;
2463 switch (*ptr++) {
2464 case 'h':
2465 if (h-- <= 0)
2466 goto invalid;
2467 switch (*ptr++) {
2468 case 'i':
2469 case 'd':
2470 case 'u':
2471 case 'o':
2472 case 'x':
2473 case 'X':
2474 return 0;
2475 default:
2476 goto invalid;
2477 }
2478 case 'i':
2479 case 'd':
2480 case 'u':
2481 case 'o':
2482 case 'x':
2483 case 'X':
2484 if (h == 0)
2485 return 0;
2486 /*FALLTHROUGH*/
2487 default:
2488 goto invalid;
2489 }
2490 #endif
2491 case 'c':
2492 if (h == 2)
2493 return 0;
2494 goto invalid;
2495 case 'i':
2496 case 'd':
2497 case 'u':
2498 case 'o':
2499 case 'x':
2500 case 'X':
2501 #ifdef STRICT_FORMAT
2502 if (h == 0)
2503 return 0;
2504 /*FALLTHROUGH*/
2505 #else
2506 return 0;
2507 #endif
2508 default:
2509 goto invalid;
2510 }
2511
2512 case FILE_FMT_FLOAT:
2513 case FILE_FMT_DOUBLE:
2514 if (*ptr == '-')
2515 ptr++;
2516 if (*ptr == '.')
2517 ptr++;
2518 CHECKLEN();
2519 if (*ptr == '.')
2520 ptr++;
2521 CHECKLEN();
2522 switch (*ptr++) {
2523 case 'e':
2524 case 'E':
2525 case 'f':
2526 case 'F':
2527 case 'g':
2528 case 'G':
2529 return 0;
2530
2531 default:
2532 goto invalid;
2533 }
2534
2535
2536 case FILE_FMT_STR:
2537 if (*ptr == '-')
2538 ptr++;
2539 while (isdigit((unsigned char )*ptr))
2540 ptr++;
2541 if (*ptr == '.') {
2542 ptr++;
2543 while (isdigit((unsigned char )*ptr))
2544 ptr++;
2545 }
2546
2547 switch (*ptr++) {
2548 case 's':
2549 return 0;
2550 default:
2551 goto invalid;
2552 }
2553
2554 default:
2555 /* internal error */
2556 abort();
2557 }
2558 invalid:
2559 *estr = "not valid";
2560 toolong:
2561 *estr = "too long";
2562 return -1;
2563 }
2564
2565 /*
2566 * Check that the optional printf format in description matches
2567 * the type of the magic.
2568 */
2569 private int
check_format(struct magic_set * ms,struct magic * m)2570 check_format(struct magic_set *ms, struct magic *m)
2571 {
2572 char *ptr;
2573 const char *estr;
2574
2575 for (ptr = m->desc; *ptr; ptr++)
2576 if (*ptr == '%')
2577 break;
2578 if (*ptr == '\0') {
2579 /* No format string; ok */
2580 return 1;
2581 }
2582
2583 assert(file_nformats == file_nnames);
2584
2585 if (m->type >= file_nformats) {
2586 file_magwarn(ms, "Internal error inconsistency between "
2587 "m->type and format strings");
2588 return -1;
2589 }
2590 if (file_formats[m->type] == FILE_FMT_NONE) {
2591 file_magwarn(ms, "No format string for `%s' with description "
2592 "`%s'", m->desc, file_names[m->type]);
2593 return -1;
2594 }
2595
2596 ptr++;
2597 if (check_format_type(ptr, m->type, &estr) == -1) {
2598 /*
2599 * TODO: this error message is unhelpful if the format
2600 * string is not one character long
2601 */
2602 file_magwarn(ms, "Printf format is %s for type "
2603 "`%s' in description `%s'", estr,
2604 file_names[m->type], m->desc);
2605 return -1;
2606 }
2607
2608 for (; *ptr; ptr++) {
2609 if (*ptr == '%') {
2610 file_magwarn(ms,
2611 "Too many format strings (should have at most one) "
2612 "for `%s' with description `%s'",
2613 file_names[m->type], m->desc);
2614 return -1;
2615 }
2616 }
2617 return 0;
2618 }
2619
2620 /*
2621 * Read a numeric value from a pointer, into the value union of a magic
2622 * pointer, according to the magic type. Update the string pointer to point
2623 * just after the number read. Return 0 for success, non-zero for failure.
2624 */
2625 private int
getvalue(struct magic_set * ms,struct magic * m,const char ** p,int action)2626 getvalue(struct magic_set *ms, struct magic *m, const char **p, int action)
2627 {
2628 char *ep;
2629 uint64_t ull;
2630
2631 switch (m->type) {
2632 case FILE_BESTRING16:
2633 case FILE_LESTRING16:
2634 case FILE_STRING:
2635 case FILE_PSTRING:
2636 case FILE_REGEX:
2637 case FILE_SEARCH:
2638 case FILE_NAME:
2639 case FILE_USE:
2640 case FILE_DER:
2641 *p = getstr(ms, m, *p, action == FILE_COMPILE);
2642 if (*p == NULL) {
2643 if (ms->flags & MAGIC_CHECK)
2644 file_magwarn(ms, "cannot get string from `%s'",
2645 m->value.s);
2646 return -1;
2647 }
2648 if (m->type == FILE_REGEX) {
2649 file_regex_t rx;
2650 int rc = file_regcomp(&rx, m->value.s, REG_EXTENDED);
2651 if (rc) {
2652 if (ms->flags & MAGIC_CHECK)
2653 file_regerror(&rx, rc, ms);
2654 }
2655 file_regfree(&rx);
2656 return rc ? -1 : 0;
2657 }
2658 return 0;
2659 default:
2660 if (m->reln == 'x')
2661 return 0;
2662 break;
2663 }
2664
2665 switch (m->type) {
2666 case FILE_FLOAT:
2667 case FILE_BEFLOAT:
2668 case FILE_LEFLOAT:
2669 errno = 0;
2670 #ifdef HAVE_STRTOF
2671 m->value.f = strtof(*p, &ep);
2672 #else
2673 m->value.f = (float)strtod(*p, &ep);
2674 #endif
2675 if (errno == 0)
2676 *p = ep;
2677 return 0;
2678 case FILE_DOUBLE:
2679 case FILE_BEDOUBLE:
2680 case FILE_LEDOUBLE:
2681 errno = 0;
2682 m->value.d = strtod(*p, &ep);
2683 if (errno == 0)
2684 *p = ep;
2685 return 0;
2686 default:
2687 errno = 0;
2688 ull = (uint64_t)strtoull(*p, &ep, 0);
2689 m->value.q = file_signextend(ms, m, ull);
2690 if (*p == ep) {
2691 file_magwarn(ms, "Unparseable number `%s'", *p);
2692 } else {
2693 size_t ts = typesize(m->type);
2694 uint64_t x;
2695 const char *q;
2696
2697 if (ts == (size_t)~0) {
2698 file_magwarn(ms,
2699 "Expected numeric type got `%s'",
2700 type_tbl[m->type].name);
2701 }
2702 for (q = *p; isspace((unsigned char)*q); q++)
2703 continue;
2704 if (*q == '-')
2705 ull = -(int64_t)ull;
2706 switch (ts) {
2707 case 1:
2708 x = (uint64_t)(ull & ~0xffULL);
2709 break;
2710 case 2:
2711 x = (uint64_t)(ull & ~0xffffULL);
2712 break;
2713 case 4:
2714 x = (uint64_t)(ull & ~0xffffffffULL);
2715 break;
2716 case 8:
2717 x = 0;
2718 break;
2719 default:
2720 abort();
2721 }
2722 if (x) {
2723 file_magwarn(ms, "Overflow for numeric"
2724 " type `%s' value %#" PRIx64,
2725 type_tbl[m->type].name, ull);
2726 }
2727 }
2728 if (errno == 0) {
2729 *p = ep;
2730 eatsize(p);
2731 }
2732 return 0;
2733 }
2734 }
2735
2736 /*
2737 * Convert a string containing C character escapes. Stop at an unescaped
2738 * space or tab.
2739 * Copy the converted version to "m->value.s", and the length in m->vallen.
2740 * Return updated scan pointer as function result. Warn if set.
2741 */
2742 private const char *
getstr(struct magic_set * ms,struct magic * m,const char * s,int warn)2743 getstr(struct magic_set *ms, struct magic *m, const char *s, int warn)
2744 {
2745 const char *origs = s;
2746 char *p = m->value.s;
2747 size_t plen = sizeof(m->value.s);
2748 char *origp = p;
2749 char *pmax = p + plen - 1;
2750 int c;
2751 int val;
2752
2753 while ((c = *s++) != '\0') {
2754 if (isspace((unsigned char) c))
2755 break;
2756 if (p >= pmax) {
2757 file_error(ms, 0, "string too long: `%s'", origs);
2758 return NULL;
2759 }
2760 if (c == '\\') {
2761 switch(c = *s++) {
2762
2763 case '\0':
2764 if (warn)
2765 file_magwarn(ms, "incomplete escape");
2766 s--;
2767 goto out;
2768
2769 case '\t':
2770 if (warn) {
2771 file_magwarn(ms,
2772 "escaped tab found, use \\t instead");
2773 warn = 0; /* already did */
2774 }
2775 /*FALLTHROUGH*/
2776 default:
2777 if (warn) {
2778 if (isprint((unsigned char)c)) {
2779 /* Allow escaping of
2780 * ``relations'' */
2781 if (strchr("<>&^=!", c) == NULL
2782 && (m->type != FILE_REGEX ||
2783 strchr("[]().*?^$|{}", c)
2784 == NULL)) {
2785 file_magwarn(ms, "no "
2786 "need to escape "
2787 "`%c'", c);
2788 }
2789 } else {
2790 file_magwarn(ms,
2791 "unknown escape sequence: "
2792 "\\%03o", c);
2793 }
2794 }
2795 /*FALLTHROUGH*/
2796 /* space, perhaps force people to use \040? */
2797 case ' ':
2798 #if 0
2799 /*
2800 * Other things people escape, but shouldn't need to,
2801 * so we disallow them
2802 */
2803 case '\'':
2804 case '"':
2805 case '?':
2806 #endif
2807 /* Relations */
2808 case '>':
2809 case '<':
2810 case '&':
2811 case '^':
2812 case '=':
2813 case '!':
2814 /* and baskslash itself */
2815 case '\\':
2816 *p++ = (char) c;
2817 break;
2818
2819 case 'a':
2820 *p++ = '\a';
2821 break;
2822
2823 case 'b':
2824 *p++ = '\b';
2825 break;
2826
2827 case 'f':
2828 *p++ = '\f';
2829 break;
2830
2831 case 'n':
2832 *p++ = '\n';
2833 break;
2834
2835 case 'r':
2836 *p++ = '\r';
2837 break;
2838
2839 case 't':
2840 *p++ = '\t';
2841 break;
2842
2843 case 'v':
2844 *p++ = '\v';
2845 break;
2846
2847 /* \ and up to 3 octal digits */
2848 case '0':
2849 case '1':
2850 case '2':
2851 case '3':
2852 case '4':
2853 case '5':
2854 case '6':
2855 case '7':
2856 val = c - '0';
2857 c = *s++; /* try for 2 */
2858 if (c >= '0' && c <= '7') {
2859 val = (val << 3) | (c - '0');
2860 c = *s++; /* try for 3 */
2861 if (c >= '0' && c <= '7')
2862 val = (val << 3) | (c-'0');
2863 else
2864 --s;
2865 }
2866 else
2867 --s;
2868 *p++ = (char)val;
2869 break;
2870
2871 /* \x and up to 2 hex digits */
2872 case 'x':
2873 val = 'x'; /* Default if no digits */
2874 c = hextoint(*s++); /* Get next char */
2875 if (c >= 0) {
2876 val = c;
2877 c = hextoint(*s++);
2878 if (c >= 0)
2879 val = (val << 4) + c;
2880 else
2881 --s;
2882 } else
2883 --s;
2884 *p++ = (char)val;
2885 break;
2886 }
2887 } else
2888 *p++ = (char)c;
2889 }
2890 --s;
2891 out:
2892 *p = '\0';
2893 m->vallen = CAST(unsigned char, (p - origp));
2894 if (m->type == FILE_PSTRING)
2895 m->vallen += (unsigned char)file_pstring_length_size(m);
2896 return s;
2897 }
2898
2899
2900 /* Single hex char to int; -1 if not a hex char. */
2901 private int
hextoint(int c)2902 hextoint(int c)
2903 {
2904 if (!isascii((unsigned char) c))
2905 return -1;
2906 if (isdigit((unsigned char) c))
2907 return c - '0';
2908 if ((c >= 'a') && (c <= 'f'))
2909 return c + 10 - 'a';
2910 if (( c>= 'A') && (c <= 'F'))
2911 return c + 10 - 'A';
2912 return -1;
2913 }
2914
2915
2916 /*
2917 * Print a string containing C character escapes.
2918 */
2919 protected void
file_showstr(FILE * fp,const char * s,size_t len)2920 file_showstr(FILE *fp, const char *s, size_t len)
2921 {
2922 char c;
2923
2924 for (;;) {
2925 if (len == ~0U) {
2926 c = *s++;
2927 if (c == '\0')
2928 break;
2929 }
2930 else {
2931 if (len-- == 0)
2932 break;
2933 c = *s++;
2934 }
2935 if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */
2936 (void) fputc(c, fp);
2937 else {
2938 (void) fputc('\\', fp);
2939 switch (c) {
2940 case '\a':
2941 (void) fputc('a', fp);
2942 break;
2943
2944 case '\b':
2945 (void) fputc('b', fp);
2946 break;
2947
2948 case '\f':
2949 (void) fputc('f', fp);
2950 break;
2951
2952 case '\n':
2953 (void) fputc('n', fp);
2954 break;
2955
2956 case '\r':
2957 (void) fputc('r', fp);
2958 break;
2959
2960 case '\t':
2961 (void) fputc('t', fp);
2962 break;
2963
2964 case '\v':
2965 (void) fputc('v', fp);
2966 break;
2967
2968 default:
2969 (void) fprintf(fp, "%.3o", c & 0377);
2970 break;
2971 }
2972 }
2973 }
2974 }
2975
2976 /*
2977 * eatsize(): Eat the size spec from a number [eg. 10UL]
2978 */
2979 private void
eatsize(const char ** p)2980 eatsize(const char **p)
2981 {
2982 const char *l = *p;
2983
2984 if (LOWCASE(*l) == 'u')
2985 l++;
2986
2987 switch (LOWCASE(*l)) {
2988 case 'l': /* long */
2989 case 's': /* short */
2990 case 'h': /* short */
2991 case 'b': /* char/byte */
2992 case 'c': /* char/byte */
2993 l++;
2994 /*FALLTHROUGH*/
2995 default:
2996 break;
2997 }
2998
2999 *p = l;
3000 }
3001
3002 /*
3003 * handle a buffer containing a compiled file.
3004 */
3005 private struct magic_map *
apprentice_buf(struct magic_set * ms,struct magic * buf,size_t len)3006 apprentice_buf(struct magic_set *ms, struct magic *buf, size_t len)
3007 {
3008 struct magic_map *map;
3009
3010 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3011 file_oomem(ms, sizeof(*map));
3012 return NULL;
3013 }
3014 map->len = len;
3015 map->p = buf;
3016 map->type = MAP_TYPE_USER;
3017 if (check_buffer(ms, map, "buffer") != 0) {
3018 apprentice_unmap(map);
3019 return NULL;
3020 }
3021 return map;
3022 }
3023
3024 /*
3025 * handle a compiled file.
3026 */
3027
3028 private struct magic_map *
apprentice_map(struct magic_set * ms,const char * fn)3029 apprentice_map(struct magic_set *ms, const char *fn)
3030 {
3031 int fd;
3032 struct stat st;
3033 char *dbname = NULL;
3034 struct magic_map *map;
3035 struct magic_map *rv = NULL;
3036
3037 fd = -1;
3038 if ((map = CAST(struct magic_map *, calloc(1, sizeof(*map)))) == NULL) {
3039 file_oomem(ms, sizeof(*map));
3040 goto error;
3041 }
3042 map->type = MAP_TYPE_USER; /* unspecified */
3043
3044 dbname = mkdbname(ms, fn, 0);
3045 if (dbname == NULL)
3046 goto error;
3047
3048 if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1)
3049 goto error;
3050
3051 if (fstat(fd, &st) == -1) {
3052 file_error(ms, errno, "cannot stat `%s'", dbname);
3053 goto error;
3054 }
3055 if (st.st_size < 8 || st.st_size > MAXMAGIC_SIZE) {
3056 file_error(ms, 0, "file `%s' is too %s", dbname,
3057 st.st_size < 8 ? "small" : "large");
3058 goto error;
3059 }
3060
3061 map->len = (size_t)st.st_size;
3062 #ifdef QUICK
3063 map->type = MAP_TYPE_MMAP;
3064 if ((map->p = mmap(0, (size_t)st.st_size, PROT_READ|PROT_WRITE,
3065 MAP_PRIVATE|MAP_FILE, fd, (off_t)0)) == MAP_FAILED) {
3066 file_error(ms, errno, "cannot map `%s'", dbname);
3067 goto error;
3068 }
3069 #else
3070 map->type = MAP_TYPE_MALLOC;
3071 if ((map->p = CAST(void *, malloc(map->len))) == NULL) {
3072 file_oomem(ms, map->len);
3073 goto error;
3074 }
3075 if (read(fd, map->p, map->len) != (ssize_t)map->len) {
3076 file_badread(ms);
3077 goto error;
3078 }
3079 #define RET 1
3080 #endif
3081 (void)close(fd);
3082 fd = -1;
3083
3084 if (check_buffer(ms, map, dbname) != 0) {
3085 rv = (struct magic_map *)-1;
3086 goto error;
3087 }
3088 #ifdef QUICK
3089 if (mprotect(map->p, (size_t)st.st_size, PROT_READ) == -1) {
3090 file_error(ms, errno, "cannot mprotect `%s'", dbname);
3091 goto error;
3092 }
3093 #endif
3094
3095 free(dbname);
3096 return map;
3097
3098 error:
3099 if (fd != -1)
3100 (void)close(fd);
3101 apprentice_unmap(map);
3102 free(dbname);
3103 return rv;
3104 }
3105
3106 private int
check_buffer(struct magic_set * ms,struct magic_map * map,const char * dbname)3107 check_buffer(struct magic_set *ms, struct magic_map *map, const char *dbname)
3108 {
3109 uint32_t *ptr;
3110 uint32_t entries, nentries;
3111 uint32_t version;
3112 int i, needsbyteswap;
3113
3114 ptr = CAST(uint32_t *, map->p);
3115 if (*ptr != MAGICNO) {
3116 if (swap4(*ptr) != MAGICNO) {
3117 file_error(ms, 0, "bad magic in `%s'", dbname);
3118 return -1;
3119 }
3120 needsbyteswap = 1;
3121 } else
3122 needsbyteswap = 0;
3123 if (needsbyteswap)
3124 version = swap4(ptr[1]);
3125 else
3126 version = ptr[1];
3127 if (version != VERSIONNO) {
3128 file_error(ms, 0, "File %s supports only version %d magic "
3129 "files. `%s' is version %d", VERSION,
3130 VERSIONNO, dbname, version);
3131 return -1;
3132 }
3133 entries = (uint32_t)(map->len / sizeof(struct magic));
3134 if ((entries * sizeof(struct magic)) != map->len) {
3135 file_error(ms, 0, "Size of `%s' %" SIZE_T_FORMAT "u is not "
3136 "a multiple of %" SIZE_T_FORMAT "u",
3137 dbname, map->len, sizeof(struct magic));
3138 return -1;
3139 }
3140 map->magic[0] = CAST(struct magic *, map->p) + 1;
3141 nentries = 0;
3142 for (i = 0; i < MAGIC_SETS; i++) {
3143 if (needsbyteswap)
3144 map->nmagic[i] = swap4(ptr[i + 2]);
3145 else
3146 map->nmagic[i] = ptr[i + 2];
3147 if (i != MAGIC_SETS - 1)
3148 map->magic[i + 1] = map->magic[i] + map->nmagic[i];
3149 nentries += map->nmagic[i];
3150 }
3151 if (entries != nentries + 1) {
3152 file_error(ms, 0, "Inconsistent entries in `%s' %u != %u",
3153 dbname, entries, nentries + 1);
3154 return -1;
3155 }
3156 if (needsbyteswap)
3157 for (i = 0; i < MAGIC_SETS; i++)
3158 byteswap(map->magic[i], map->nmagic[i]);
3159 return 0;
3160 }
3161
3162 /*
3163 * handle an mmaped file.
3164 */
3165 private int
apprentice_compile(struct magic_set * ms,struct magic_map * map,const char * fn)3166 apprentice_compile(struct magic_set *ms, struct magic_map *map, const char *fn)
3167 {
3168 static const size_t nm = sizeof(*map->nmagic) * MAGIC_SETS;
3169 static const size_t m = sizeof(**map->magic);
3170 int fd = -1;
3171 size_t len;
3172 char *dbname;
3173 int rv = -1;
3174 uint32_t i;
3175 union {
3176 struct magic m;
3177 uint32_t h[2 + MAGIC_SETS];
3178 } hdr;
3179
3180 dbname = mkdbname(ms, fn, 1);
3181
3182 if (dbname == NULL)
3183 goto out;
3184
3185 if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1)
3186 {
3187 file_error(ms, errno, "cannot open `%s'", dbname);
3188 goto out;
3189 }
3190 memset(&hdr, 0, sizeof(hdr));
3191 hdr.h[0] = MAGICNO;
3192 hdr.h[1] = VERSIONNO;
3193 memcpy(hdr.h + 2, map->nmagic, nm);
3194
3195 if (write(fd, &hdr, sizeof(hdr)) != (ssize_t)sizeof(hdr)) {
3196 file_error(ms, errno, "error writing `%s'", dbname);
3197 goto out2;
3198 }
3199
3200 for (i = 0; i < MAGIC_SETS; i++) {
3201 len = m * map->nmagic[i];
3202 if (write(fd, map->magic[i], len) != (ssize_t)len) {
3203 file_error(ms, errno, "error writing `%s'", dbname);
3204 goto out2;
3205 }
3206 }
3207
3208 rv = 0;
3209 out2:
3210 if (fd != -1)
3211 (void)close(fd);
3212 out:
3213 apprentice_unmap(map);
3214 free(dbname);
3215 return rv;
3216 }
3217
3218 private const char ext[] = ".mgc";
3219 /*
3220 * make a dbname
3221 */
3222 private char *
mkdbname(struct magic_set * ms,const char * fn,int strip)3223 mkdbname(struct magic_set *ms, const char *fn, int strip)
3224 {
3225 const char *p, *q;
3226 char *buf;
3227
3228 if (strip) {
3229 if ((p = strrchr(fn, '/')) != NULL)
3230 fn = ++p;
3231 }
3232
3233 for (q = fn; *q; q++)
3234 continue;
3235 /* Look for .mgc */
3236 for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--)
3237 if (*p != *q)
3238 break;
3239
3240 /* Did not find .mgc, restore q */
3241 if (p >= ext)
3242 while (*q)
3243 q++;
3244
3245 q++;
3246 /* Compatibility with old code that looked in .mime */
3247 if (ms->flags & MAGIC_MIME) {
3248 if (asprintf(&buf, "%.*s.mime%s", (int)(q - fn), fn, ext) < 0)
3249 return NULL;
3250 if (access(buf, R_OK) != -1) {
3251 ms->flags &= MAGIC_MIME_TYPE;
3252 return buf;
3253 }
3254 free(buf);
3255 }
3256 if (asprintf(&buf, "%.*s%s", (int)(q - fn), fn, ext) < 0)
3257 return NULL;
3258
3259 /* Compatibility with old code that looked in .mime */
3260 if (strstr(fn, ".mime") != NULL)
3261 ms->flags &= MAGIC_MIME_TYPE;
3262 return buf;
3263 }
3264
3265 /*
3266 * Byteswap an mmap'ed file if needed
3267 */
3268 private void
byteswap(struct magic * magic,uint32_t nmagic)3269 byteswap(struct magic *magic, uint32_t nmagic)
3270 {
3271 uint32_t i;
3272 for (i = 0; i < nmagic; i++)
3273 bs1(&magic[i]);
3274 }
3275
3276 /*
3277 * swap a short
3278 */
3279 private uint16_t
swap2(uint16_t sv)3280 swap2(uint16_t sv)
3281 {
3282 uint16_t rv;
3283 uint8_t *s = (uint8_t *)(void *)&sv;
3284 uint8_t *d = (uint8_t *)(void *)&rv;
3285 d[0] = s[1];
3286 d[1] = s[0];
3287 return rv;
3288 }
3289
3290 /*
3291 * swap an int
3292 */
3293 private uint32_t
swap4(uint32_t sv)3294 swap4(uint32_t sv)
3295 {
3296 uint32_t rv;
3297 uint8_t *s = (uint8_t *)(void *)&sv;
3298 uint8_t *d = (uint8_t *)(void *)&rv;
3299 d[0] = s[3];
3300 d[1] = s[2];
3301 d[2] = s[1];
3302 d[3] = s[0];
3303 return rv;
3304 }
3305
3306 /*
3307 * swap a quad
3308 */
3309 private uint64_t
swap8(uint64_t sv)3310 swap8(uint64_t sv)
3311 {
3312 uint64_t rv;
3313 uint8_t *s = (uint8_t *)(void *)&sv;
3314 uint8_t *d = (uint8_t *)(void *)&rv;
3315 #if 0
3316 d[0] = s[3];
3317 d[1] = s[2];
3318 d[2] = s[1];
3319 d[3] = s[0];
3320 d[4] = s[7];
3321 d[5] = s[6];
3322 d[6] = s[5];
3323 d[7] = s[4];
3324 #else
3325 d[0] = s[7];
3326 d[1] = s[6];
3327 d[2] = s[5];
3328 d[3] = s[4];
3329 d[4] = s[3];
3330 d[5] = s[2];
3331 d[6] = s[1];
3332 d[7] = s[0];
3333 #endif
3334 return rv;
3335 }
3336
3337 /*
3338 * byteswap a single magic entry
3339 */
3340 private void
bs1(struct magic * m)3341 bs1(struct magic *m)
3342 {
3343 m->cont_level = swap2(m->cont_level);
3344 m->offset = swap4((uint32_t)m->offset);
3345 m->in_offset = swap4((uint32_t)m->in_offset);
3346 m->lineno = swap4((uint32_t)m->lineno);
3347 if (IS_STRING(m->type)) {
3348 m->str_range = swap4(m->str_range);
3349 m->str_flags = swap4(m->str_flags);
3350 }
3351 else {
3352 m->value.q = swap8(m->value.q);
3353 m->num_mask = swap8(m->num_mask);
3354 }
3355 }
3356
3357 protected size_t
file_pstring_length_size(const struct magic * m)3358 file_pstring_length_size(const struct magic *m)
3359 {
3360 switch (m->str_flags & PSTRING_LEN) {
3361 case PSTRING_1_LE:
3362 return 1;
3363 case PSTRING_2_LE:
3364 case PSTRING_2_BE:
3365 return 2;
3366 case PSTRING_4_LE:
3367 case PSTRING_4_BE:
3368 return 4;
3369 default:
3370 abort(); /* Impossible */
3371 return 1;
3372 }
3373 }
3374 protected size_t
file_pstring_get_length(const struct magic * m,const char * ss)3375 file_pstring_get_length(const struct magic *m, const char *ss)
3376 {
3377 size_t len = 0;
3378 const unsigned char *s = (const unsigned char *)ss;
3379 unsigned int s3, s2, s1, s0;
3380
3381 switch (m->str_flags & PSTRING_LEN) {
3382 case PSTRING_1_LE:
3383 len = *s;
3384 break;
3385 case PSTRING_2_LE:
3386 s0 = s[0];
3387 s1 = s[1];
3388 len = (s1 << 8) | s0;
3389 break;
3390 case PSTRING_2_BE:
3391 s0 = s[0];
3392 s1 = s[1];
3393 len = (s0 << 8) | s1;
3394 break;
3395 case PSTRING_4_LE:
3396 s0 = s[0];
3397 s1 = s[1];
3398 s2 = s[2];
3399 s3 = s[3];
3400 len = (s3 << 24) | (s2 << 16) | (s1 << 8) | s0;
3401 break;
3402 case PSTRING_4_BE:
3403 s0 = s[0];
3404 s1 = s[1];
3405 s2 = s[2];
3406 s3 = s[3];
3407 len = (s0 << 24) | (s1 << 16) | (s2 << 8) | s3;
3408 break;
3409 default:
3410 abort(); /* Impossible */
3411 }
3412
3413 if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF)
3414 len -= file_pstring_length_size(m);
3415
3416 return len;
3417 }
3418
3419 protected int
file_magicfind(struct magic_set * ms,const char * name,struct mlist * v)3420 file_magicfind(struct magic_set *ms, const char *name, struct mlist *v)
3421 {
3422 uint32_t i, j;
3423 struct mlist *mlist, *ml;
3424
3425 mlist = ms->mlist[1];
3426
3427 for (ml = mlist->next; ml != mlist; ml = ml->next) {
3428 struct magic *ma = ml->magic;
3429 uint32_t nma = ml->nmagic;
3430 for (i = 0; i < nma; i++) {
3431 if (ma[i].type != FILE_NAME)
3432 continue;
3433 if (strcmp(ma[i].value.s, name) == 0) {
3434 v->magic = &ma[i];
3435 for (j = i + 1; j < nma; j++)
3436 if (ma[j].cont_level == 0)
3437 break;
3438 v->nmagic = j - i;
3439 return 0;
3440 }
3441 }
3442 }
3443 return -1;
3444 }
3445