xref: /PHP-7.4/ext/fileinfo/libmagic/fsmagic.c (revision 622b10f0)
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 1.80 2019/04/23 18:59:27 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 HAVE_SYS_SYSMACROS_H
50 # include <sys/sysmacros.h>
51 #endif
52 #ifdef MAJOR_IN_SYSMACROS
53 # define HAVE_MAJOR
54 #endif
55 #if defined(major) && !defined(HAVE_MAJOR)
56 /* Might be defined in sys/types.h.  */
57 # define HAVE_MAJOR
58 #endif
59 #ifdef WIN32
60 # define WIN32_LEAN_AND_MEAN
61 # include <windows.h>
62 #endif
63 
64 #ifndef HAVE_MAJOR
65 # define major(dev)  (((dev) >> 8) & 0xff)
66 # define minor(dev)  ((dev) & 0xff)
67 #endif
68 #undef HAVE_MAJOR
69 
70 #ifdef PHP_WIN32
71 
72 # undef S_IFIFO
73 #endif
74 private int
handle_mime(struct magic_set * ms,int mime,const char * str)75 handle_mime(struct magic_set *ms, int mime, const char *str)
76 {
77 	if ((mime & MAGIC_MIME_TYPE)) {
78 		if (file_printf(ms, "inode/%s", str) == -1)
79 			return -1;
80 		if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms,
81 		    "; charset=") == -1)
82 			return -1;
83 	}
84 	if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, "binary") == -1)
85 		return -1;
86 	return 0;
87 }
88 
89 protected int
file_fsmagic(struct magic_set * ms,const char * fn,zend_stat_t * sb)90 file_fsmagic(struct magic_set *ms, const char *fn, zend_stat_t *sb)
91 {
92 	int ret, did = 0;
93 	int mime = ms->flags & MAGIC_MIME;
94 	int silent = ms->flags & (MAGIC_APPLE|MAGIC_EXTENSION);
95 
96 	if (fn == NULL)
97 		return 0;
98 
99 #define COMMA	(did++ ? ", " : "")
100 	ret = php_sys_stat(fn, sb);
101 
102 	if (ret) {
103 		if (ms->flags & MAGIC_ERROR) {
104 			file_error(ms, errno, "cannot stat `%s'", fn);
105 			return -1;
106 		}
107 		if (file_printf(ms, "cannot open `%s' (%s)",
108 		    fn, strerror(errno)) == -1)
109 			return -1;
110 		return 0;
111 	}
112 
113 	ret = 1;
114 	if (!mime && !silent) {
115 #ifdef S_ISUID
116 		if (sb->st_mode & S_ISUID)
117 			if (file_printf(ms, "%ssetuid", COMMA) == -1)
118 				return -1;
119 #endif
120 #ifdef S_ISGID
121 		if (sb->st_mode & S_ISGID)
122 			if (file_printf(ms, "%ssetgid", COMMA) == -1)
123 				return -1;
124 #endif
125 #ifdef S_ISVTX
126 		if (sb->st_mode & S_ISVTX)
127 			if (file_printf(ms, "%ssticky", COMMA) == -1)
128 				return -1;
129 #endif
130 	}
131 
132 	switch (sb->st_mode & S_IFMT) {
133 #ifndef PHP_WIN32
134 # ifdef S_IFCHR
135 		case S_IFCHR:
136 			/*
137 			 * If -s has been specified, treat character special files
138 			 * like ordinary files.  Otherwise, just report that they
139 			 * are block special files and go on to the next file.
140 			 */
141 			if ((ms->flags & MAGIC_DEVICES) != 0) {
142 				ret = 0;
143 				break;
144 			}
145 			if (mime) {
146 				if (handle_mime(ms, mime, "chardevice") == -1)
147 					return -1;
148 			} else {
149 #  ifdef HAVE_STAT_ST_RDEV
150 #   ifdef dv_unit
151 			if (file_printf(ms, "%scharacter special (%d/%d/%d)",
152 			    COMMA, major(sb->st_rdev), dv_unit(sb->st_rdev),
153 					dv_subunit(sb->st_rdev)) == -1)
154 				return -1;
155 # else
156 			if (file_printf(ms, "%scharacter special (%ld/%ld)",
157 			    COMMA, (long)major(sb->st_rdev),
158 			    (long)minor(sb->st_rdev)) == -1)
159 				return -1;
160 # endif
161 #else
162 			if (file_printf(ms, "%scharacter special", COMMA) == -1)
163 				return -1;
164 #endif
165 	}
166 			return 1;
167 # endif
168 #endif
169 
170 #ifdef	S_IFIFO
171 	case S_IFIFO:
172 		if((ms->flags & MAGIC_DEVICES) != 0)
173 			break;
174 		if (mime) {
175 			if (handle_mime(ms, mime, "fifo") == -1)
176 				return -1;
177 		} else if (silent) {
178 		} else if (file_printf(ms, "%sfifo (named pipe)", COMMA) == -1)
179 			return -1;
180 		break;
181 #endif
182 #ifdef	S_IFDOOR
183 	case S_IFDOOR:
184 		if (mime) {
185 			if (handle_mime(ms, mime, "door") == -1)
186 				return -1;
187 		} else if (silent) {
188 		} else if (file_printf(ms, "%sdoor", COMMA) == -1)
189 			return -1;
190 		break;
191 #endif
192 #ifdef	S_IFLNK
193 	case S_IFLNK:
194 		/* stat is used, if it made here then the link is broken */
195 			if (ms->flags & MAGIC_ERROR) {
196 			    file_error(ms, errno, "unreadable symlink `%s'", fn);
197 			    return -1;
198 			}
199 	return 1;
200 #endif
201 
202 #ifdef	S_IFSOCK
203 #ifndef __COHERENT__
204 	case S_IFSOCK:
205 		if (mime) {
206 			if (handle_mime(ms, mime, "socket") == -1)
207 				return -1;
208 		} else if (silent) {
209 		} else if (file_printf(ms, "%ssocket", COMMA) == -1)
210 			return -1;
211 		break;
212 #endif
213 #endif
214 	case S_IFREG:
215 		/*
216 		 * regular file, check next possibility
217 		 *
218 		 * If stat() tells us the file has zero length, report here that
219 		 * the file is empty, so we can skip all the work of opening and
220 		 * reading the file.
221 		 * But if the -s option has been given, we skip this
222 		 * optimization, since on some systems, stat() reports zero
223 		 * size for raw disk partitions. (If the block special device
224 		 * really has zero length, the fact that it is empty will be
225 		 * detected and reported correctly when we read the file.)
226 		 */
227 		if ((ms->flags & MAGIC_DEVICES) == 0 && sb->st_size == 0) {
228 			if (mime) {
229 				if (handle_mime(ms, mime, "x-empty") == -1)
230 					return -1;
231 			} else if (silent) {
232 			} else if (file_printf(ms, "%sempty", COMMA) == -1)
233 				return -1;
234 			break;
235 		}
236 		ret = 0;
237 		break;
238 
239 	default:
240 		file_error(ms, 0, "invalid mode 0%o", sb->st_mode);
241 		return -1;
242 		/*NOTREACHED*/
243 	}
244 
245 	if (!silent && !mime && did && ret == 0) {
246 	    if (file_printf(ms, " ") == -1)
247 		    return -1;
248 	}
249 	return ret;
250 }
251