1 /*
2 * Copyright (c) Christos Zoulas 2003.
3 * All Rights Reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice immediately at the beginning of the file, without modification,
10 * this list of conditions, and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
19 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include "file.h"
29
30 #ifndef lint
31 FILE_RCSID("@(#)$File: magic.c,v 1.91 2014/12/16 23:18:40 christos Exp $")
32 #endif /* lint */
33
34 #include "magic.h"
35
36 #include <stdlib.h>
37 #ifdef PHP_WIN32
38 #include "win32/unistd.h"
39 #else
40 #include <unistd.h>
41 #endif
42 #include <string.h>
43 #ifdef PHP_WIN32
44 # include "config.w32.h"
45 #else
46 # include "php_config.h"
47 #endif
48
49 #ifdef PHP_WIN32
50 #include <shlwapi.h>
51 #endif
52
53 #include <limits.h> /* for PIPE_BUF */
54
55 #if defined(HAVE_UTIMES)
56 # include <sys/time.h>
57 #elif defined(HAVE_UTIME)
58 # if defined(HAVE_SYS_UTIME_H)
59 # include <sys/utime.h>
60 # elif defined(HAVE_UTIME_H)
61 # include <utime.h>
62 # endif
63 #endif
64
65 #ifdef HAVE_UNISTD_H
66 #include <unistd.h> /* for read() */
67 #endif
68
69 #ifndef PIPE_BUF
70 /* Get the PIPE_BUF from pathconf */
71 #ifdef _PC_PIPE_BUF
72 #define PIPE_BUF pathconf(".", _PC_PIPE_BUF)
73 #else
74 #define PIPE_BUF 512
75 #endif
76 #endif
77
78 #ifdef PHP_WIN32
79 # undef S_IFLNK
80 # undef S_IFIFO
81 #endif
82
83 private void close_and_restore(const struct magic_set *, const char *, int,
84 const zend_stat_t *);
85 private int unreadable_info(struct magic_set *, mode_t, const char *);
86 #if 0
87 private const char* get_default_magic(void);
88 #endif
89 private const char *file_or_stream(struct magic_set *, const char *, php_stream *);
90
91 #ifndef STDIN_FILENO
92 #define STDIN_FILENO 0
93 #endif
94
95 /* XXX this functionality is excluded in php, enable it in apprentice.c:340 */
96 #if 0
97 private const char *
98 get_default_magic(void)
99 {
100 static const char hmagic[] = "/.magic/magic.mgc";
101 static char *default_magic;
102 char *home, *hmagicpath;
103
104 #ifndef PHP_WIN32
105 struct stat st;
106
107 if (default_magic) {
108 free(default_magic);
109 default_magic = NULL;
110 }
111 if ((home = getenv("HOME")) == NULL)
112 return MAGIC;
113
114 if (asprintf(&hmagicpath, "%s/.magic.mgc", home) < 0)
115 return MAGIC;
116 if (stat(hmagicpath, &st) == -1) {
117 free(hmagicpath);
118 if (asprintf(&hmagicpath, "%s/.magic", home) < 0)
119 return MAGIC;
120 if (stat(hmagicpath, &st) == -1)
121 goto out;
122 if (S_ISDIR(st.st_mode)) {
123 free(hmagicpath);
124 if (asprintf(&hmagicpath, "%s/%s", home, hmagic) < 0)
125 return MAGIC;
126 if (access(hmagicpath, R_OK) == -1)
127 goto out;
128 }
129 }
130
131 if (asprintf(&default_magic, "%s:%s", hmagicpath, MAGIC) < 0)
132 goto out;
133 free(hmagicpath);
134 return default_magic;
135 out:
136 default_magic = NULL;
137 free(hmagicpath);
138 return MAGIC;
139 #else
140 char *hmagicp = hmagicpath;
141 char *tmppath = NULL;
142 LPTSTR dllpath;
143
144 #define APPENDPATH() \
145 do { \
146 if (tmppath && access(tmppath, R_OK) != -1) { \
147 if (hmagicpath == NULL) \
148 hmagicpath = tmppath; \
149 else { \
150 if (asprintf(&hmagicp, "%s%c%s", hmagicpath, \
151 PATHSEP, tmppath) >= 0) { \
152 free(hmagicpath); \
153 hmagicpath = hmagicp; \
154 } \
155 free(tmppath); \
156 } \
157 tmppath = NULL; \
158 } \
159 } while (/*CONSTCOND*/0)
160
161 if (default_magic) {
162 free(default_magic);
163 default_magic = NULL;
164 }
165
166 /* First, try to get user-specific magic file */
167 if ((home = getenv("LOCALAPPDATA")) == NULL) {
168 if ((home = getenv("USERPROFILE")) != NULL)
169 if (asprintf(&tmppath,
170 "%s/Local Settings/Application Data%s", home,
171 hmagic) < 0)
172 tmppath = NULL;
173 } else {
174 if (asprintf(&tmppath, "%s%s", home, hmagic) < 0)
175 tmppath = NULL;
176 }
177
178 APPENDPATH();
179
180 /* Second, try to get a magic file from Common Files */
181 if ((home = getenv("COMMONPROGRAMFILES")) != NULL) {
182 if (asprintf(&tmppath, "%s%s", home, hmagic) >= 0)
183 APPENDPATH();
184 }
185
186 /* Third, try to get magic file relative to dll location */
187 dllpath = malloc(sizeof(*dllpath) * (MAX_PATH + 1));
188 dllpath[MAX_PATH] = 0; /* just in case long path gets truncated and not null terminated */
189 if (GetModuleFileNameA(NULL, dllpath, MAX_PATH)){
190 PathRemoveFileSpecA(dllpath);
191 if (strlen(dllpath) > 3 &&
192 stricmp(&dllpath[strlen(dllpath) - 3], "bin") == 0) {
193 if (asprintf(&tmppath,
194 "%s/../share/misc/magic.mgc", dllpath) >= 0)
195 APPENDPATH();
196 } else {
197 if (asprintf(&tmppath,
198 "%s/share/misc/magic.mgc", dllpath) >= 0)
199 APPENDPATH();
200 else if (asprintf(&tmppath,
201 "%s/magic.mgc", dllpath) >= 0)
202 APPENDPATH();
203 }
204 }
205
206 /* Don't put MAGIC constant - it likely points to a file within MSys
207 tree */
208 default_magic = hmagicpath;
209 return default_magic;
210 #endif
211 }
212
213 public const char *
214 magic_getpath(const char *magicfile, int action)
215 {
216 if (magicfile != NULL)
217 return magicfile;
218
219 magicfile = getenv("MAGIC");
220 if (magicfile != NULL)
221 return magicfile;
222
223 return action == FILE_LOAD ? get_default_magic() : MAGIC;
224 }
225 #endif
226
227 public struct magic_set *
magic_open(int flags)228 magic_open(int flags)
229 {
230 return file_ms_alloc(flags);
231 }
232
233 private int
unreadable_info(struct magic_set * ms,mode_t md,const char * file)234 unreadable_info(struct magic_set *ms, mode_t md, const char *file)
235 {
236 if (file) {
237 /* We cannot open it, but we were able to stat it. */
238 if (access(file, W_OK) == 0)
239 if (file_printf(ms, "writable, ") == -1)
240 return -1;
241 if (access(file, X_OK) == 0)
242 if (file_printf(ms, "executable, ") == -1)
243 return -1;
244 }
245 if (S_ISREG(md))
246 if (file_printf(ms, "regular file, ") == -1)
247 return -1;
248 if (file_printf(ms, "no read permission") == -1)
249 return -1;
250 return 0;
251 }
252
253 public void
magic_close(struct magic_set * ms)254 magic_close(struct magic_set *ms)
255 {
256 if (ms == NULL)
257 return;
258 file_ms_free(ms);
259 }
260
261 /*
262 * load a magic file
263 */
264 public int
magic_load(struct magic_set * ms,const char * magicfile)265 magic_load(struct magic_set *ms, const char *magicfile)
266 {
267 if (ms == NULL)
268 return -1;
269 return file_apprentice(ms, magicfile, FILE_LOAD);
270 }
271
272 public int
magic_compile(struct magic_set * ms,const char * magicfile)273 magic_compile(struct magic_set *ms, const char *magicfile)
274 {
275 if (ms == NULL)
276 return -1;
277 return file_apprentice(ms, magicfile, FILE_COMPILE);
278 }
279
280
281 public int
magic_list(struct magic_set * ms,const char * magicfile)282 magic_list(struct magic_set *ms, const char *magicfile)
283 {
284 if (ms == NULL)
285 return -1;
286 return file_apprentice(ms, magicfile, FILE_LIST);
287 }
288
289 private void
close_and_restore(const struct magic_set * ms,const char * name,int fd,const zend_stat_t * sb)290 close_and_restore(const struct magic_set *ms, const char *name, int fd,
291 const zend_stat_t *sb)
292 {
293
294 if ((ms->flags & MAGIC_PRESERVE_ATIME) != 0) {
295 /*
296 * Try to restore access, modification times if read it.
297 * This is really *bad* because it will modify the status
298 * time of the file... And of course this will affect
299 * backup programs
300 */
301 #ifdef HAVE_UTIMES
302 struct timeval utsbuf[2];
303 (void)memset(utsbuf, 0, sizeof(utsbuf));
304 utsbuf[0].tv_sec = sb->st_atime;
305 utsbuf[1].tv_sec = sb->st_mtime;
306
307 (void) utimes(name, utsbuf); /* don't care if loses */
308 #elif defined(HAVE_UTIME_H) || defined(HAVE_SYS_UTIME_H)
309 struct utimbuf utbuf;
310
311 (void)memset(&utbuf, 0, sizeof(utbuf));
312 utbuf.actime = sb->st_atime;
313 utbuf.modtime = sb->st_mtime;
314 (void) utime(name, &utbuf); /* don't care if loses */
315 #endif
316 }
317 }
318
319
320 /*
321 * find type of descriptor
322 */
323 public const char *
magic_descriptor(struct magic_set * ms,int fd)324 magic_descriptor(struct magic_set *ms, int fd)
325 {
326 if (ms == NULL)
327 return NULL;
328 return file_or_stream(ms, NULL, NULL);
329 }
330
331 /*
332 * find type of named file
333 */
334 public const char *
magic_file(struct magic_set * ms,const char * inname)335 magic_file(struct magic_set *ms, const char *inname)
336 {
337 if (ms == NULL)
338 return NULL;
339 return file_or_stream(ms, inname, NULL);
340 }
341
342 public const char *
magic_stream(struct magic_set * ms,php_stream * stream)343 magic_stream(struct magic_set *ms, php_stream *stream)
344 {
345 if (ms == NULL)
346 return NULL;
347 return file_or_stream(ms, NULL, stream);
348 }
349
350 private const char *
file_or_stream(struct magic_set * ms,const char * inname,php_stream * stream)351 file_or_stream(struct magic_set *ms, const char *inname, php_stream *stream)
352 {
353 int rv = -1;
354 unsigned char *buf;
355 zend_stat_t sb;
356 ssize_t nbytes = 0; /* number of bytes read from a datafile */
357 int no_in_stream = 0;
358
359 if (!inname && !stream) {
360 return NULL;
361 }
362
363 /*
364 * one extra for terminating '\0', and
365 * some overlapping space for matches near EOF
366 */
367 #define SLOP (1 + sizeof(union VALUETYPE))
368 buf = emalloc(HOWMANY + SLOP);
369
370 if (file_reset(ms) == -1)
371 goto done;
372
373 switch (file_fsmagic(ms, inname, &sb, stream)) {
374 case -1: /* error */
375 goto done;
376 case 0: /* nothing found */
377 break;
378 default: /* matched it and printed type */
379 rv = 0;
380 goto done;
381 }
382
383 errno = 0;
384
385 if (!stream && inname) {
386 no_in_stream = 1;
387 stream = php_stream_open_wrapper((char *)inname, "rb", REPORT_ERRORS, NULL);
388 }
389
390 if (!stream) {
391 if (unreadable_info(ms, sb.st_mode, inname) == -1)
392 goto done;
393 rv = 0;
394 goto done;
395 }
396
397 #ifdef O_NONBLOCK
398 /* we should be already be in non blocking mode for network socket */
399 #endif
400
401 /*
402 * try looking at the first HOWMANY bytes
403 */
404 if ((nbytes = php_stream_read(stream, (char *)buf, HOWMANY)) < 0) {
405 file_error(ms, errno, "cannot read `%s'", inname);
406 goto done;
407 }
408
409 (void)memset(buf + nbytes, 0, SLOP); /* NUL terminate */
410 if (file_buffer(ms, stream, inname, buf, (size_t)nbytes) == -1)
411 goto done;
412 rv = 0;
413 done:
414 efree(buf);
415
416 if (no_in_stream && stream) {
417 php_stream_close(stream);
418 }
419
420 close_and_restore(ms, inname, 0, &sb);
421 return rv == 0 ? file_getbuffer(ms) : NULL;
422 }
423
424
425 public const char *
magic_buffer(struct magic_set * ms,const void * buf,size_t nb)426 magic_buffer(struct magic_set *ms, const void *buf, size_t nb)
427 {
428 if (ms == NULL)
429 return NULL;
430 if (file_reset(ms) == -1)
431 return NULL;
432 /*
433 * The main work is done here!
434 * We have the file name and/or the data buffer to be identified.
435 */
436 if (file_buffer(ms, NULL, NULL, buf, nb) == -1) {
437 return NULL;
438 }
439 return file_getbuffer(ms);
440 }
441
442 public const char *
magic_error(struct magic_set * ms)443 magic_error(struct magic_set *ms)
444 {
445 if (ms == NULL)
446 return "Magic database is not open";
447 return (ms->event_flags & EVENT_HAD_ERR) ? ms->o.buf : NULL;
448 }
449
450 public int
magic_errno(struct magic_set * ms)451 magic_errno(struct magic_set *ms)
452 {
453 if (ms == NULL)
454 return EINVAL;
455 return (ms->event_flags & EVENT_HAD_ERR) ? ms->error : 0;
456 }
457
458 public int
magic_setflags(struct magic_set * ms,int flags)459 magic_setflags(struct magic_set *ms, int flags)
460 {
461 if (ms == NULL)
462 return -1;
463 #if !defined(HAVE_UTIME) && !defined(HAVE_UTIMES)
464 if (flags & MAGIC_PRESERVE_ATIME)
465 return -1;
466 #endif
467 ms->flags = flags;
468 return 0;
469 }
470
471 public int
magic_version(void)472 magic_version(void)
473 {
474 return MAGIC_VERSION;
475 }
476
477 public int
magic_setparam(struct magic_set * ms,int param,const void * val)478 magic_setparam(struct magic_set *ms, int param, const void *val)
479 {
480 switch (param) {
481 case MAGIC_PARAM_INDIR_MAX:
482 ms->indir_max = (uint16_t)*(const size_t *)val;
483 return 0;
484 case MAGIC_PARAM_NAME_MAX:
485 ms->name_max = (uint16_t)*(const size_t *)val;
486 return 0;
487 case MAGIC_PARAM_ELF_PHNUM_MAX:
488 ms->elf_phnum_max = (uint16_t)*(const size_t *)val;
489 return 0;
490 case MAGIC_PARAM_ELF_SHNUM_MAX:
491 ms->elf_shnum_max = (uint16_t)*(const size_t *)val;
492 return 0;
493 case MAGIC_PARAM_ELF_NOTES_MAX:
494 ms->elf_notes_max = (uint16_t)*(const size_t *)val;
495 return 0;
496 default:
497 errno = EINVAL;
498 return -1;
499 }
500 }
501
502 public int
magic_getparam(struct magic_set * ms,int param,void * val)503 magic_getparam(struct magic_set *ms, int param, void *val)
504 {
505 switch (param) {
506 case MAGIC_PARAM_INDIR_MAX:
507 *(size_t *)val = ms->indir_max;
508 return 0;
509 case MAGIC_PARAM_NAME_MAX:
510 *(size_t *)val = ms->name_max;
511 return 0;
512 case MAGIC_PARAM_ELF_PHNUM_MAX:
513 *(size_t *)val = ms->elf_phnum_max;
514 return 0;
515 case MAGIC_PARAM_ELF_SHNUM_MAX:
516 *(size_t *)val = ms->elf_shnum_max;
517 return 0;
518 case MAGIC_PARAM_ELF_NOTES_MAX:
519 *(size_t *)val = ms->elf_notes_max;
520 return 0;
521 default:
522 errno = EINVAL;
523 return -1;
524 }
525 }
526
