xref: /PHP-7.1/ext/fileinfo/libmagic/fsmagic.c (revision d5558138)
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  * fsmagic - magic based on filesystem info - directory, special files, etc.
30  */
31 
32 #include "file.h"
33 
34 #ifndef	lint
35 FILE_RCSID("@(#)$File: fsmagic.c,v 1.74 2014/10/13 20:21:49 christos Exp $")
36 #endif	/* lint */
37 
38 #include "magic.h"
39 #include <string.h>
40 #ifdef HAVE_UNISTD_H
41 #include <unistd.h>
42 #endif
43 #include <stdlib.h>
44 /* Since major is a function on SVR4, we cannot use `ifndef major'.  */
45 #ifdef MAJOR_IN_MKDEV
46 # include <sys/mkdev.h>
47 # define HAVE_MAJOR
48 #endif
49 #ifdef MAJOR_IN_SYSMACROS
50 # include <sys/sysmacros.h>
51 # define HAVE_MAJOR
52 #endif
53 #ifdef major			/* Might be defined in sys/types.h.  */
54 # define HAVE_MAJOR
55 #endif
56 #ifdef WIN32
57 # define WIN32_LEAN_AND_MEAN
58 # include <windows.h>
59 #endif
60 
61 #ifndef HAVE_MAJOR
62 # define major(dev)  (((dev) >> 8) & 0xff)
63 # define minor(dev)  ((dev) & 0xff)
64 #endif
65 #undef HAVE_MAJOR
66 
67 #ifdef PHP_WIN32
68 
69 # undef S_IFIFO
70 #endif
71 
72 
73 #ifndef S_ISDIR
74 #define S_ISDIR(mode) ((mode) & _S_IFDIR)
75 #endif
76 
77 #ifndef S_ISREG
78 #define S_ISREG(mode) ((mode) & _S_IFREG)
79 #endif
80 
81 private int
handle_mime(struct magic_set * ms,int mime,const char * str)82 handle_mime(struct magic_set *ms, int mime, const char *str)
83 {
84 	if ((mime & MAGIC_MIME_TYPE)) {
85 		if (file_printf(ms, "inode/%s", str) == -1)
86 			return -1;
87 		if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms,
88 		    "; charset=") == -1)
89 			return -1;
90 	}
91 	if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, "binary") == -1)
92 		return -1;
93 	return 0;
94 }
95 
96 protected int
file_fsmagic(struct magic_set * ms,const char * fn,zend_stat_t * sb,php_stream * stream)97 file_fsmagic(struct magic_set *ms, const char *fn, zend_stat_t *sb, php_stream *stream)
98 {
99 	int ret, did = 0;
100 	int mime = ms->flags & MAGIC_MIME;
101 
102 	if (ms->flags & MAGIC_APPLE)
103 		return 0;
104 
105 	if (fn == NULL && !stream) {
106 		return 0;
107 	}
108 
109 #define COMMA	(did++ ? ", " : "")
110 
111 	if (stream) {
112 		php_stream_statbuf ssb;
113 		if (php_stream_stat(stream, &ssb) < 0) {
114 			if (ms->flags & MAGIC_ERROR) {
115 				file_error(ms, errno, "cannot stat `%s'", fn);
116 				return -1;
117 			}
118 			return 0;
119 		}
120 		memcpy(sb, &ssb.sb, sizeof(struct stat));
121 	} else {
122 		if (php_sys_stat(fn, sb) != 0) {
123 			if (ms->flags & MAGIC_ERROR) {
124 				file_error(ms, errno, "cannot stat `%s'", fn);
125 				return -1;
126 			}
127 			return 0;
128 		}
129 	}
130 
131 	ret = 1;
132 	if (!mime) {
133 #ifdef S_ISUID
134 		if (sb->st_mode & S_ISUID)
135 			if (file_printf(ms, "%ssetuid", COMMA) == -1)
136 				return -1;
137 #endif
138 #ifdef S_ISGID
139 		if (sb->st_mode & S_ISGID)
140 			if (file_printf(ms, "%ssetgid", COMMA) == -1)
141 				return -1;
142 #endif
143 #ifdef S_ISVTX
144 		if (sb->st_mode & S_ISVTX)
145 			if (file_printf(ms, "%ssticky", COMMA) == -1)
146 				return -1;
147 #endif
148 	}
149 
150 	switch (sb->st_mode & S_IFMT) {
151 #ifndef PHP_WIN32
152 # ifdef S_IFCHR
153 		case S_IFCHR:
154 			/*
155 			 * If -s has been specified, treat character special files
156 			 * like ordinary files.  Otherwise, just report that they
157 			 * are block special files and go on to the next file.
158 			 */
159 			if ((ms->flags & MAGIC_DEVICES) != 0) {
160 				ret = 0;
161 				break;
162 			}
163 			if (mime) {
164 				if (handle_mime(ms, mime, "chardevice") == -1)
165 					return -1;
166 			} else {
167 #  ifdef HAVE_STAT_ST_RDEV
168 #   ifdef dv_unit
169 			if (file_printf(ms, "%scharacter special (%d/%d/%d)",
170 			    COMMA, major(sb->st_rdev), dv_unit(sb->st_rdev),
171 					dv_subunit(sb->st_rdev)) == -1)
172 				return -1;
173 # else
174 			if (file_printf(ms, "%scharacter special (%ld/%ld)",
175 			    COMMA, (long)major(sb->st_rdev),
176 			    (long)minor(sb->st_rdev)) == -1)
177 				return -1;
178 # endif
179 #else
180 			if (file_printf(ms, "%scharacter special", COMMA) == -1)
181 				return -1;
182 #endif
183 	}
184 			return 1;
185 # endif
186 #endif
187 
188 #ifdef	S_IFIFO
189 	case S_IFIFO:
190 		if((ms->flags & MAGIC_DEVICES) != 0)
191 			break;
192 		if (mime) {
193 			if (handle_mime(ms, mime, "fifo") == -1)
194 				return -1;
195 		} else if (file_printf(ms, "%sfifo (named pipe)", COMMA) == -1)
196 			return -1;
197 		break;
198 #endif
199 #ifdef	S_IFDOOR
200 	case S_IFDOOR:
201 		if (mime) {
202 			if (handle_mime(ms, mime, "door") == -1)
203 				return -1;
204 		} else if (file_printf(ms, "%sdoor", COMMA) == -1)
205 			return -1;
206 		break;
207 #endif
208 #ifdef	S_IFLNK
209 	case S_IFLNK:
210 		/* stat is used, if it made here then the link is broken */
211 			if (ms->flags & MAGIC_ERROR) {
212 			    file_error(ms, errno, "unreadable symlink `%s'", fn);
213 			    return -1;
214 			}
215 	return 1;
216 #endif
217 
218 #ifdef	S_IFSOCK
219 #ifndef __COHERENT__
220 	case S_IFSOCK:
221 		if (mime) {
222 			if (handle_mime(ms, mime, "socket") == -1)
223 				return -1;
224 		} else if (file_printf(ms, "%ssocket", COMMA) == -1)
225 			return -1;
226 		break;
227 #endif
228 #endif
229 	case S_IFREG:
230 		/*
231 		 * regular file, check next possibility
232 		 *
233 		 * If stat() tells us the file has zero length, report here that
234 		 * the file is empty, so we can skip all the work of opening and
235 		 * reading the file.
236 		 * But if the -s option has been given, we skip this
237 		 * optimization, since on some systems, stat() reports zero
238 		 * size for raw disk partitions. (If the block special device
239 		 * really has zero length, the fact that it is empty will be
240 		 * detected and reported correctly when we read the file.)
241 	 */
242 	if ((ms->flags & MAGIC_DEVICES) == 0 && sb->st_size == 0) {
243 		if (mime) {
244 			if (handle_mime(ms, mime, "x-empty") == -1)
245 				return -1;
246 			} else if (file_printf(ms, "%sempty", COMMA) == -1)
247 			return -1;
248 			break;
249 	}
250 		ret = 0;
251 		break;
252 
253 	default:
254 		file_error(ms, 0, "invalid mode 0%o", sb->st_mode);
255 		return -1;
256 		/*NOTREACHED*/
257 	}
258 
259 	return ret;
260 }
261