blob: 80913f542a4e19c257e9bb6de705e8b2c7713676
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Mini chmod implementation for busybox |
4 | * |
5 | * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
6 | * |
7 | * Reworked by (C) 2002 Vladimir Oleynik <dzo@simtreas.ru> |
8 | * to correctly parse '-rwxgoa' |
9 | * |
10 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
11 | */ |
12 | //config:config CHMOD |
13 | //config: bool "chmod" |
14 | //config: default y |
15 | //config: help |
16 | //config: chmod is used to change the access permission of files. |
17 | |
18 | //applet:IF_CHMOD(APPLET_NOEXEC(chmod, chmod, BB_DIR_BIN, BB_SUID_DROP, chmod)) |
19 | |
20 | //kbuild:lib-$(CONFIG_CHMOD) += chmod.o |
21 | |
22 | /* BB_AUDIT SUSv3 compliant */ |
23 | /* BB_AUDIT GNU defects - unsupported long options. */ |
24 | /* http://www.opengroup.org/onlinepubs/007904975/utilities/chmod.html */ |
25 | |
26 | //usage:#define chmod_trivial_usage |
27 | //usage: "[-R"IF_DESKTOP("cvf")"] MODE[,MODE]... FILE..." |
28 | //usage:#define chmod_full_usage "\n\n" |
29 | //usage: "Each MODE is one or more of the letters ugoa, one of the\n" |
30 | //usage: "symbols +-= and one or more of the letters rwxst\n" |
31 | //usage: "\n -R Recurse" |
32 | //usage: IF_DESKTOP( |
33 | //usage: "\n -c List changed files" |
34 | //usage: "\n -v List all files" |
35 | //usage: "\n -f Hide errors" |
36 | //usage: ) |
37 | //usage: |
38 | //usage:#define chmod_example_usage |
39 | //usage: "$ ls -l /tmp/foo\n" |
40 | //usage: "-rw-rw-r-- 1 root root 0 Apr 12 18:25 /tmp/foo\n" |
41 | //usage: "$ chmod u+x /tmp/foo\n" |
42 | //usage: "$ ls -l /tmp/foo\n" |
43 | //usage: "-rwxrw-r-- 1 root root 0 Apr 12 18:25 /tmp/foo*\n" |
44 | //usage: "$ chmod 444 /tmp/foo\n" |
45 | //usage: "$ ls -l /tmp/foo\n" |
46 | //usage: "-r--r--r-- 1 root root 0 Apr 12 18:25 /tmp/foo\n" |
47 | |
48 | #include "libbb.h" |
49 | |
50 | /* This is a NOEXEC applet. Be very careful! */ |
51 | |
52 | |
53 | #define OPT_RECURSE (option_mask32 & 1) |
54 | #define OPT_VERBOSE (IF_DESKTOP(option_mask32 & 2) IF_NOT_DESKTOP(0)) |
55 | #define OPT_CHANGED (IF_DESKTOP(option_mask32 & 4) IF_NOT_DESKTOP(0)) |
56 | #define OPT_QUIET (IF_DESKTOP(option_mask32 & 8) IF_NOT_DESKTOP(0)) |
57 | #define OPT_STR "R" IF_DESKTOP("vcf") |
58 | |
59 | /* coreutils: |
60 | * chmod never changes the permissions of symbolic links; the chmod |
61 | * system call cannot change their permissions. This is not a problem |
62 | * since the permissions of symbolic links are never used. |
63 | * However, for each symbolic link listed on the command line, chmod changes |
64 | * the permissions of the pointed-to file. In contrast, chmod ignores |
65 | * symbolic links encountered during recursive directory traversals. |
66 | */ |
67 | |
68 | static int FAST_FUNC fileAction(const char *fileName, struct stat *statbuf, void* param, int depth) |
69 | { |
70 | mode_t newmode; |
71 | |
72 | /* match coreutils behavior */ |
73 | if (depth == 0) { |
74 | /* statbuf holds lstat result, but we need stat (follow link) */ |
75 | if (stat(fileName, statbuf)) |
76 | goto err; |
77 | } else { /* depth > 0: skip links */ |
78 | if (S_ISLNK(statbuf->st_mode)) |
79 | return TRUE; |
80 | } |
81 | |
82 | newmode = bb_parse_mode((char *)param, statbuf->st_mode); |
83 | if (newmode == (mode_t)-1) |
84 | bb_error_msg_and_die("invalid mode '%s'", (char *)param); |
85 | |
86 | if (chmod(fileName, newmode) == 0) { |
87 | if (OPT_VERBOSE |
88 | || (OPT_CHANGED && statbuf->st_mode != newmode) |
89 | ) { |
90 | printf("mode of '%s' changed to %04o (%s)\n", fileName, |
91 | newmode & 07777, bb_mode_string(newmode)+1); |
92 | } |
93 | return TRUE; |
94 | } |
95 | err: |
96 | if (!OPT_QUIET) |
97 | bb_simple_perror_msg(fileName); |
98 | return FALSE; |
99 | } |
100 | |
101 | int chmod_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
102 | int chmod_main(int argc UNUSED_PARAM, char **argv) |
103 | { |
104 | int retval = EXIT_SUCCESS; |
105 | char *arg, **argp; |
106 | char *smode; |
107 | |
108 | /* Convert first encountered -r into ar, -w into aw etc |
109 | * so that getopt would not eat it */ |
110 | argp = argv; |
111 | while ((arg = *++argp)) { |
112 | /* Mode spec must be the first arg (sans -R etc) */ |
113 | /* (protect against mishandling e.g. "chmod 644 -r") */ |
114 | if (arg[0] != '-') { |
115 | arg = NULL; |
116 | break; |
117 | } |
118 | /* An option. Not a -- or valid option? */ |
119 | if (arg[1] && !strchr("-"OPT_STR, arg[1])) { |
120 | arg[0] = 'a'; |
121 | break; |
122 | } |
123 | } |
124 | |
125 | /* Parse options */ |
126 | opt_complementary = "-2"; |
127 | getopt32(argv, ("-"OPT_STR) + 1); /* Reuse string */ |
128 | argv += optind; |
129 | |
130 | /* Restore option-like mode if needed */ |
131 | if (arg) arg[0] = '-'; |
132 | |
133 | /* Ok, ready to do the deed now */ |
134 | smode = *argv++; |
135 | do { |
136 | if (!recursive_action(*argv, |
137 | OPT_RECURSE, // recurse |
138 | fileAction, // file action |
139 | fileAction, // dir action |
140 | smode, // user data |
141 | 0) // depth |
142 | ) { |
143 | retval = EXIT_FAILURE; |
144 | } |
145 | } while (*++argv); |
146 | |
147 | return retval; |
148 | } |
149 | |
150 | /* |
151 | Security: chmod is too important and too subtle. |
152 | This is a test script (busybox chmod versus coreutils). |
153 | Run it in empty directory. |
154 | |
155 | #!/bin/sh |
156 | t1="/tmp/busybox chmod" |
157 | t2="/usr/bin/chmod" |
158 | create() { |
159 | rm -rf $1; mkdir $1 |
160 | ( |
161 | cd $1 || exit 1 |
162 | mkdir dir |
163 | >up |
164 | >file |
165 | >dir/file |
166 | ln -s dir linkdir |
167 | ln -s file linkfile |
168 | ln -s ../up dir/up |
169 | ) |
170 | } |
171 | tst() { |
172 | (cd test1; $t1 $1) |
173 | (cd test2; $t2 $1) |
174 | (cd test1; ls -lR) >out1 |
175 | (cd test2; ls -lR) >out2 |
176 | echo "chmod $1" >out.diff |
177 | if ! diff -u out1 out2 >>out.diff; then exit 1; fi |
178 | rm out.diff |
179 | } |
180 | echo "If script produced 'out.diff' file, then at least one testcase failed" |
181 | create test1; create test2 |
182 | tst "a+w file" |
183 | tst "a-w dir" |
184 | tst "a+w linkfile" |
185 | tst "a-w linkdir" |
186 | tst "-R a+w file" |
187 | tst "-R a-w dir" |
188 | tst "-R a+w linkfile" |
189 | tst "-R a-w linkdir" |
190 | tst "a-r,a+x linkfile" |
191 | */ |
192 |