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 1.100 2016/07/18 11:43:05 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 #include "config.h"
44
45 #ifdef PHP_WIN32
46 #include <shlwapi.h>
47 #endif
48
49 #include <limits.h> /* for PIPE_BUF */
50
51 #if defined(HAVE_UTIMES)
52 # include <sys/time.h>
53 #elif defined(HAVE_UTIME)
54 # if defined(HAVE_SYS_UTIME_H)
55 # include <sys/utime.h>
56 # elif defined(HAVE_UTIME_H)
57 # include <utime.h>
58 # endif
59 #endif
60
61 #ifdef HAVE_UNISTD_H
62 #include <unistd.h> /* for read() */
63 #endif
64
65 #ifndef PIPE_BUF
66 /* Get the PIPE_BUF from pathconf */
67 #ifdef _PC_PIPE_BUF
68 #define PIPE_BUF pathconf(".", _PC_PIPE_BUF)
69 #else
70 #define PIPE_BUF 512
71 #endif
72 #endif
73
74 #ifdef PHP_WIN32
75 # undef S_IFLNK
76 # undef S_IFIFO
77 #endif
78
79 private void close_and_restore(const struct magic_set *, const char *, int,
80 const zend_stat_t *);
81 private int unreadable_info(struct magic_set *, mode_t, const char *);
82 #if 0
83 private const char* get_default_magic(void);
84 #endif
85 private const char *file_or_stream(struct magic_set *, const char *, php_stream *);
86
87 #ifndef STDIN_FILENO
88 #define STDIN_FILENO 0
89 #endif
90
91 public struct magic_set *
magic_open(int flags)92 magic_open(int flags)
93 {
94 return file_ms_alloc(flags);
95 }
96
97 private int
unreadable_info(struct magic_set * ms,mode_t md,const char * file)98 unreadable_info(struct magic_set *ms, mode_t md, const char *file)
99 {
100 if (file) {
101 /* We cannot open it, but we were able to stat it. */
102 if (access(file, W_OK) == 0)
103 if (file_printf(ms, "writable, ") == -1)
104 return -1;
105 if (access(file, X_OK) == 0)
106 if (file_printf(ms, "executable, ") == -1)
107 return -1;
108 }
109 if (S_ISREG(md))
110 if (file_printf(ms, "regular file, ") == -1)
111 return -1;
112 if (file_printf(ms, "no read permission") == -1)
113 return -1;
114 return 0;
115 }
116
117 public void
magic_close(struct magic_set * ms)118 magic_close(struct magic_set *ms)
119 {
120 if (ms == NULL)
121 return;
122 file_ms_free(ms);
123 }
124
125 /*
126 * load a magic file
127 */
128 public int
magic_load(struct magic_set * ms,const char * magicfile)129 magic_load(struct magic_set *ms, const char *magicfile)
130 {
131 if (ms == NULL)
132 return -1;
133 return file_apprentice(ms, magicfile, FILE_LOAD);
134 }
135
136 public int
magic_compile(struct magic_set * ms,const char * magicfile)137 magic_compile(struct magic_set *ms, const char *magicfile)
138 {
139 if (ms == NULL)
140 return -1;
141 return file_apprentice(ms, magicfile, FILE_COMPILE);
142 }
143
144
145 public int
magic_list(struct magic_set * ms,const char * magicfile)146 magic_list(struct magic_set *ms, const char *magicfile)
147 {
148 if (ms == NULL)
149 return -1;
150 return file_apprentice(ms, magicfile, FILE_LIST);
151 }
152
153 private void
close_and_restore(const struct magic_set * ms,const char * name,int fd,const zend_stat_t * sb)154 close_and_restore(const struct magic_set *ms, const char *name, int fd,
155 const zend_stat_t *sb)
156 {
157
158 if ((ms->flags & MAGIC_PRESERVE_ATIME) != 0) {
159 /*
160 * Try to restore access, modification times if read it.
161 * This is really *bad* because it will modify the status
162 * time of the file... And of course this will affect
163 * backup programs
164 */
165 #ifdef HAVE_UTIMES
166 struct timeval utsbuf[2];
167 (void)memset(utsbuf, 0, sizeof(utsbuf));
168 utsbuf[0].tv_sec = sb->st_atime;
169 utsbuf[1].tv_sec = sb->st_mtime;
170
171 (void) utimes(name, utsbuf); /* don't care if loses */
172 #elif defined(HAVE_UTIME_H) || defined(HAVE_SYS_UTIME_H)
173 struct utimbuf utbuf;
174
175 (void)memset(&utbuf, 0, sizeof(utbuf));
176 utbuf.actime = sb->st_atime;
177 utbuf.modtime = sb->st_mtime;
178 (void) utime(name, &utbuf); /* don't care if loses */
179 #endif
180 }
181 }
182
183
184 /*
185 * find type of descriptor
186 */
187 public const char *
magic_descriptor(struct magic_set * ms,int fd)188 magic_descriptor(struct magic_set *ms, int fd)
189 {
190 if (ms == NULL)
191 return NULL;
192 return file_or_stream(ms, NULL, NULL);
193 }
194
195 /*
196 * find type of named file
197 */
198 public const char *
magic_file(struct magic_set * ms,const char * inname)199 magic_file(struct magic_set *ms, const char *inname)
200 {
201 if (ms == NULL)
202 return NULL;
203 return file_or_stream(ms, inname, NULL);
204 }
205
206 public const char *
magic_stream(struct magic_set * ms,php_stream * stream)207 magic_stream(struct magic_set *ms, php_stream *stream)
208 {
209 if (ms == NULL)
210 return NULL;
211 return file_or_stream(ms, NULL, stream);
212 }
213
214 private const char *
file_or_stream(struct magic_set * ms,const char * inname,php_stream * stream)215 file_or_stream(struct magic_set *ms, const char *inname, php_stream *stream)
216 {
217 int rv = -1;
218 unsigned char *buf;
219 zend_stat_t sb;
220 ssize_t nbytes = 0; /* number of bytes read from a datafile */
221 int no_in_stream = 0;
222
223 if (file_reset(ms) == -1)
224 goto out;
225
226 if (!inname && !stream) {
227 return NULL;
228 }
229
230 /*
231 * one extra for terminating '\0', and
232 * some overlapping space for matches near EOF
233 */
234 #define SLOP (1 + sizeof(union VALUETYPE))
235 if ((buf = CAST(unsigned char *, emalloc(ms->bytes_max + SLOP))) == NULL)
236 return NULL;
237
238 switch (file_fsmagic(ms, inname, &sb, stream)) {
239 case -1: /* error */
240 goto done;
241 case 0: /* nothing found */
242 break;
243 default: /* matched it and printed type */
244 rv = 0;
245 goto done;
246 }
247
248 errno = 0;
249
250 if (!stream && inname) {
251 no_in_stream = 1;
252 stream = php_stream_open_wrapper((char *)inname, "rb", REPORT_ERRORS, NULL);
253 }
254
255 if (!stream) {
256 if (unreadable_info(ms, sb.st_mode, inname) == -1)
257 goto done;
258 rv = 0;
259 goto done;
260 }
261
262 #ifdef O_NONBLOCK
263 /* we should be already be in non blocking mode for network socket */
264 #endif
265
266 /*
267 * try looking at the first ms->bytes_max bytes
268 */
269 if ((nbytes = php_stream_read(stream, (char *)buf, ms->bytes_max - nbytes)) < 0) {
270 file_error(ms, errno, "cannot read `%s'", inname);
271 goto done;
272 }
273
274 (void)memset(buf + nbytes, 0, SLOP); /* NUL terminate */
275 if (file_buffer(ms, stream, inname, buf, (size_t)nbytes) == -1)
276 goto done;
277 rv = 0;
278 done:
279 efree(buf);
280
281 if (no_in_stream && stream) {
282 php_stream_close(stream);
283 }
284 out:
285 return rv == 0 ? file_getbuffer(ms) : NULL;
286 }
287
288
289 public const char *
magic_buffer(struct magic_set * ms,const void * buf,size_t nb)290 magic_buffer(struct magic_set *ms, const void *buf, size_t nb)
291 {
292 if (ms == NULL)
293 return NULL;
294 if (file_reset(ms) == -1)
295 return NULL;
296 /*
297 * The main work is done here!
298 * We have the file name and/or the data buffer to be identified.
299 */
300 if (file_buffer(ms, NULL, NULL, buf, nb) == -1) {
301 return NULL;
302 }
303 return file_getbuffer(ms);
304 }
305
306 public const char *
magic_error(struct magic_set * ms)307 magic_error(struct magic_set *ms)
308 {
309 if (ms == NULL)
310 return "Magic database is not open";
311 return (ms->event_flags & EVENT_HAD_ERR) ? ms->o.buf : NULL;
312 }
313
314 public int
magic_errno(struct magic_set * ms)315 magic_errno(struct magic_set *ms)
316 {
317 if (ms == NULL)
318 return EINVAL;
319 return (ms->event_flags & EVENT_HAD_ERR) ? ms->error : 0;
320 }
321
322 public int
magic_setflags(struct magic_set * ms,int flags)323 magic_setflags(struct magic_set *ms, int flags)
324 {
325 if (ms == NULL)
326 return -1;
327 #if !defined(HAVE_UTIME) && !defined(HAVE_UTIMES)
328 if (flags & MAGIC_PRESERVE_ATIME)
329 return -1;
330 #endif
331 ms->flags = flags;
332 return 0;
333 }
334
335 public int
magic_version(void)336 magic_version(void)
337 {
338 return MAGIC_VERSION;
339 }
340
341 public int
magic_setparam(struct magic_set * ms,int param,const void * val)342 magic_setparam(struct magic_set *ms, int param, const void *val)
343 {
344 switch (param) {
345 case MAGIC_PARAM_INDIR_MAX:
346 ms->indir_max = (uint16_t)*(const size_t *)val;
347 return 0;
348 case MAGIC_PARAM_NAME_MAX:
349 ms->name_max = (uint16_t)*(const size_t *)val;
350 return 0;
351 case MAGIC_PARAM_ELF_PHNUM_MAX:
352 ms->elf_phnum_max = (uint16_t)*(const size_t *)val;
353 return 0;
354 case MAGIC_PARAM_ELF_SHNUM_MAX:
355 ms->elf_shnum_max = (uint16_t)*(const size_t *)val;
356 return 0;
357 case MAGIC_PARAM_ELF_NOTES_MAX:
358 ms->elf_notes_max = (uint16_t)*(const size_t *)val;
359 return 0;
360 case MAGIC_PARAM_REGEX_MAX:
361 ms->elf_notes_max = (uint16_t)*(const size_t *)val;
362 return 0;
363 case MAGIC_PARAM_BYTES_MAX:
364 ms->bytes_max = *(const size_t *)val;
365 return 0;
366 default:
367 errno = EINVAL;
368 return -1;
369 }
370 }
371
372 public int
magic_getparam(struct magic_set * ms,int param,void * val)373 magic_getparam(struct magic_set *ms, int param, void *val)
374 {
375 switch (param) {
376 case MAGIC_PARAM_INDIR_MAX:
377 *(size_t *)val = ms->indir_max;
378 return 0;
379 case MAGIC_PARAM_NAME_MAX:
380 *(size_t *)val = ms->name_max;
381 return 0;
382 case MAGIC_PARAM_ELF_PHNUM_MAX:
383 *(size_t *)val = ms->elf_phnum_max;
384 return 0;
385 case MAGIC_PARAM_ELF_SHNUM_MAX:
386 *(size_t *)val = ms->elf_shnum_max;
387 return 0;
388 case MAGIC_PARAM_ELF_NOTES_MAX:
389 *(size_t *)val = ms->elf_notes_max;
390 return 0;
391 case MAGIC_PARAM_REGEX_MAX:
392 *(size_t *)val = ms->regex_max;
393 return 0;
394 case MAGIC_PARAM_BYTES_MAX:
395 *(size_t *)val = ms->bytes_max;
396 return 0;
397 default:
398 errno = EINVAL;
399 return -1;
400 }
401 }
402
