xref: /freebsd/bin/chmod/chmod.c (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, 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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static char const copyright[] =
35 "@(#) Copyright (c) 1989, 1993, 1994\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #endif
40 #include <sys/cdefs.h>
41 #include <sys/param.h>
42 #include <sys/stat.h>
43 
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <fts.h>
48 #include <limits.h>
49 #include <signal.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 
55 static volatile sig_atomic_t siginfo;
56 
57 static void usage(void) __dead2;
58 static int may_have_nfs4acl(const FTSENT *ent, int hflag);
59 
60 static void
61 siginfo_handler(int sig __unused)
62 {
63 
64 	siginfo = 1;
65 }
66 
67 int
68 main(int argc, char *argv[])
69 {
70 	FTS *ftsp;
71 	FTSENT *p;
72 	mode_t *set;
73 	int Hflag, Lflag, Rflag, ch, fflag, fts_options, hflag, rval;
74 	int vflag;
75 	char *mode;
76 	mode_t newmode;
77 
78 	set = NULL;
79 	Hflag = Lflag = Rflag = fflag = hflag = vflag = 0;
80 	while ((ch = getopt(argc, argv, "HLPRXfghorstuvwx")) != -1)
81 		switch (ch) {
82 		case 'H':
83 			Hflag = 1;
84 			Lflag = 0;
85 			break;
86 		case 'L':
87 			Lflag = 1;
88 			Hflag = 0;
89 			break;
90 		case 'P':
91 			Hflag = Lflag = 0;
92 			break;
93 		case 'R':
94 			Rflag = 1;
95 			break;
96 		case 'f':
97 			fflag = 1;
98 			break;
99 		case 'h':
100 			/*
101 			 * In System V the -h option causes chmod to change
102 			 * the mode of the symbolic link. 4.4BSD's symbolic
103 			 * links didn't have modes, so it was an undocumented
104 			 * noop.  In FreeBSD 3.0, lchmod(2) is introduced and
105 			 * this option does real work.
106 			 */
107 			hflag = 1;
108 			break;
109 		/*
110 		 * XXX
111 		 * "-[rwx]" are valid mode commands.  If they are the entire
112 		 * argument, getopt has moved past them, so decrement optind.
113 		 * Regardless, we're done argument processing.
114 		 */
115 		case 'g': case 'o': case 'r': case 's':
116 		case 't': case 'u': case 'w': case 'X': case 'x':
117 			if (argv[optind - 1][0] == '-' &&
118 			    argv[optind - 1][1] == ch &&
119 			    argv[optind - 1][2] == '\0')
120 				--optind;
121 			goto done;
122 		case 'v':
123 			vflag++;
124 			break;
125 		case '?':
126 		default:
127 			usage();
128 		}
129 done:	argv += optind;
130 	argc -= optind;
131 
132 	if (argc < 2)
133 		usage();
134 
135 	(void)signal(SIGINFO, siginfo_handler);
136 
137 	if (Rflag) {
138 		if (hflag)
139 			errx(1, "the -R and -h options may not be "
140 			    "specified together.");
141 		if (Lflag) {
142 			fts_options = FTS_LOGICAL;
143 		} else {
144 			fts_options = FTS_PHYSICAL;
145 
146 			if (Hflag) {
147 				fts_options |= FTS_COMFOLLOW;
148 			}
149 		}
150 	} else if (hflag) {
151 		fts_options = FTS_PHYSICAL;
152 	} else {
153 		fts_options = FTS_LOGICAL;
154 	}
155 
156 	mode = *argv;
157 	if ((set = setmode(mode)) == NULL)
158 		errx(1, "invalid file mode: %s", mode);
159 
160 	if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
161 		err(1, "fts_open");
162 	for (rval = 0; errno = 0, (p = fts_read(ftsp)) != NULL;) {
163 		int atflag;
164 
165 		if ((fts_options & FTS_LOGICAL) ||
166 		    ((fts_options & FTS_COMFOLLOW) &&
167 		    p->fts_level == FTS_ROOTLEVEL))
168 			atflag = 0;
169 		else
170 			atflag = AT_SYMLINK_NOFOLLOW;
171 
172 		switch (p->fts_info) {
173 		case FTS_D:
174 			if (!Rflag)
175 				fts_set(ftsp, p, FTS_SKIP);
176 			break;
177 		case FTS_DNR:			/* Warn, chmod. */
178 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
179 			rval = 1;
180 			break;
181 		case FTS_DP:			/* Already changed at FTS_D. */
182 			continue;
183 		case FTS_ERR:			/* Warn, continue. */
184 		case FTS_NS:
185 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
186 			rval = 1;
187 			continue;
188 		default:
189 			break;
190 		}
191 		newmode = getmode(set, p->fts_statp->st_mode);
192 		/*
193 		 * With NFSv4 ACLs, it is possible that applying a mode
194 		 * identical to the one computed from an ACL will change
195 		 * that ACL.
196 		 */
197 		if (may_have_nfs4acl(p, hflag) == 0 &&
198 		    (newmode & ALLPERMS) == (p->fts_statp->st_mode & ALLPERMS))
199 				continue;
200 		if (fchmodat(AT_FDCWD, p->fts_accpath, newmode, atflag) == -1
201 		    && !fflag) {
202 			warn("%s", p->fts_path);
203 			rval = 1;
204 		} else if (vflag || siginfo) {
205 			(void)printf("%s", p->fts_path);
206 
207 			if (vflag > 1 || siginfo) {
208 				char m1[12], m2[12];
209 
210 				strmode(p->fts_statp->st_mode, m1);
211 				strmode((p->fts_statp->st_mode &
212 				    S_IFMT) | newmode, m2);
213 				(void)printf(": 0%o [%s] -> 0%o [%s]",
214 				    p->fts_statp->st_mode, m1,
215 				    (p->fts_statp->st_mode & S_IFMT) |
216 				    newmode, m2);
217 			}
218 			(void)printf("\n");
219 			siginfo = 0;
220 		}
221 	}
222 	if (errno)
223 		err(1, "fts_read");
224 	exit(rval);
225 }
226 
227 static void
228 usage(void)
229 {
230 	(void)fprintf(stderr,
231 	    "usage: chmod [-fhv] [-R [-H | -L | -P]] mode file ...\n");
232 	exit(1);
233 }
234 
235 static int
236 may_have_nfs4acl(const FTSENT *ent, int hflag)
237 {
238 	int ret;
239 	static dev_t previous_dev = NODEV;
240 	static int supports_acls = -1;
241 
242 	if (previous_dev != ent->fts_statp->st_dev) {
243 		previous_dev = ent->fts_statp->st_dev;
244 		supports_acls = 0;
245 
246 		if (hflag)
247 			ret = lpathconf(ent->fts_accpath, _PC_ACL_NFS4);
248 		else
249 			ret = pathconf(ent->fts_accpath, _PC_ACL_NFS4);
250 		if (ret > 0)
251 			supports_acls = 1;
252 		else if (ret < 0 && errno != EINVAL)
253 			warn("%s", ent->fts_path);
254 	}
255 
256 	return (supports_acls);
257 }
258