xref: /freebsd/bin/chmod/chmod.c (revision 1843dfb05ed80149f5a412180af882e3cb8f451b)
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 #ifndef lint
40 static char sccsid[] = "@(#)chmod.c	8.8 (Berkeley) 4/1/94";
41 #endif /* not lint */
42 #endif
43 #include <sys/cdefs.h>
44 #include <sys/param.h>
45 #include <sys/stat.h>
46 
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <fts.h>
51 #include <limits.h>
52 #include <signal.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 
58 static volatile sig_atomic_t siginfo;
59 
60 static void usage(void) __dead2;
61 static int may_have_nfs4acl(const FTSENT *ent, int hflag);
62 
63 static void
64 siginfo_handler(int sig __unused)
65 {
66 
67 	siginfo = 1;
68 }
69 
70 int
71 main(int argc, char *argv[])
72 {
73 	FTS *ftsp;
74 	FTSENT *p;
75 	mode_t *set;
76 	int Hflag, Lflag, Rflag, ch, fflag, fts_options, hflag, rval;
77 	int vflag;
78 	char *mode;
79 	mode_t newmode;
80 
81 	set = NULL;
82 	Hflag = Lflag = Rflag = fflag = hflag = vflag = 0;
83 	while ((ch = getopt(argc, argv, "HLPRXfghorstuvwx")) != -1)
84 		switch (ch) {
85 		case 'H':
86 			Hflag = 1;
87 			Lflag = 0;
88 			break;
89 		case 'L':
90 			Lflag = 1;
91 			Hflag = 0;
92 			break;
93 		case 'P':
94 			Hflag = Lflag = 0;
95 			break;
96 		case 'R':
97 			Rflag = 1;
98 			break;
99 		case 'f':
100 			fflag = 1;
101 			break;
102 		case 'h':
103 			/*
104 			 * In System V the -h option causes chmod to change
105 			 * the mode of the symbolic link. 4.4BSD's symbolic
106 			 * links didn't have modes, so it was an undocumented
107 			 * noop.  In FreeBSD 3.0, lchmod(2) is introduced and
108 			 * this option does real work.
109 			 */
110 			hflag = 1;
111 			break;
112 		/*
113 		 * XXX
114 		 * "-[rwx]" are valid mode commands.  If they are the entire
115 		 * argument, getopt has moved past them, so decrement optind.
116 		 * Regardless, we're done argument processing.
117 		 */
118 		case 'g': case 'o': case 'r': case 's':
119 		case 't': case 'u': case 'w': case 'X': case 'x':
120 			if (argv[optind - 1][0] == '-' &&
121 			    argv[optind - 1][1] == ch &&
122 			    argv[optind - 1][2] == '\0')
123 				--optind;
124 			goto done;
125 		case 'v':
126 			vflag++;
127 			break;
128 		case '?':
129 		default:
130 			usage();
131 		}
132 done:	argv += optind;
133 	argc -= optind;
134 
135 	if (argc < 2)
136 		usage();
137 
138 	(void)signal(SIGINFO, siginfo_handler);
139 
140 	if (Rflag) {
141 		if (hflag)
142 			errx(1, "the -R and -h options may not be "
143 			    "specified together.");
144 		if (Lflag) {
145 			fts_options = FTS_LOGICAL;
146 		} else {
147 			fts_options = FTS_PHYSICAL;
148 
149 			if (Hflag) {
150 				fts_options |= FTS_COMFOLLOW;
151 			}
152 		}
153 	} else if (hflag) {
154 		fts_options = FTS_PHYSICAL;
155 	} else {
156 		fts_options = FTS_LOGICAL;
157 	}
158 
159 	mode = *argv;
160 	if ((set = setmode(mode)) == NULL)
161 		errx(1, "invalid file mode: %s", mode);
162 
163 	if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
164 		err(1, "fts_open");
165 	for (rval = 0; errno = 0, (p = fts_read(ftsp)) != NULL;) {
166 		int atflag;
167 
168 		if ((fts_options & FTS_LOGICAL) ||
169 		    ((fts_options & FTS_COMFOLLOW) &&
170 		    p->fts_level == FTS_ROOTLEVEL))
171 			atflag = 0;
172 		else
173 			atflag = AT_SYMLINK_NOFOLLOW;
174 
175 		switch (p->fts_info) {
176 		case FTS_D:
177 			if (!Rflag)
178 				fts_set(ftsp, p, FTS_SKIP);
179 			break;
180 		case FTS_DNR:			/* Warn, chmod. */
181 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
182 			rval = 1;
183 			break;
184 		case FTS_DP:			/* Already changed at FTS_D. */
185 			continue;
186 		case FTS_ERR:			/* Warn, continue. */
187 		case FTS_NS:
188 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
189 			rval = 1;
190 			continue;
191 		default:
192 			break;
193 		}
194 		newmode = getmode(set, p->fts_statp->st_mode);
195 		/*
196 		 * With NFSv4 ACLs, it is possible that applying a mode
197 		 * identical to the one computed from an ACL will change
198 		 * that ACL.
199 		 */
200 		if (may_have_nfs4acl(p, hflag) == 0 &&
201 		    (newmode & ALLPERMS) == (p->fts_statp->st_mode & ALLPERMS))
202 				continue;
203 		if (fchmodat(AT_FDCWD, p->fts_accpath, newmode, atflag) == -1
204 		    && !fflag) {
205 			warn("%s", p->fts_path);
206 			rval = 1;
207 		} else if (vflag || siginfo) {
208 			(void)printf("%s", p->fts_path);
209 
210 			if (vflag > 1 || siginfo) {
211 				char m1[12], m2[12];
212 
213 				strmode(p->fts_statp->st_mode, m1);
214 				strmode((p->fts_statp->st_mode &
215 				    S_IFMT) | newmode, m2);
216 				(void)printf(": 0%o [%s] -> 0%o [%s]",
217 				    p->fts_statp->st_mode, m1,
218 				    (p->fts_statp->st_mode & S_IFMT) |
219 				    newmode, m2);
220 			}
221 			(void)printf("\n");
222 			siginfo = 0;
223 		}
224 	}
225 	if (errno)
226 		err(1, "fts_read");
227 	exit(rval);
228 }
229 
230 static void
231 usage(void)
232 {
233 	(void)fprintf(stderr,
234 	    "usage: chmod [-fhv] [-R [-H | -L | -P]] mode file ...\n");
235 	exit(1);
236 }
237 
238 static int
239 may_have_nfs4acl(const FTSENT *ent, int hflag)
240 {
241 	int ret;
242 	static dev_t previous_dev = NODEV;
243 	static int supports_acls = -1;
244 
245 	if (previous_dev != ent->fts_statp->st_dev) {
246 		previous_dev = ent->fts_statp->st_dev;
247 		supports_acls = 0;
248 
249 		if (hflag)
250 			ret = lpathconf(ent->fts_accpath, _PC_ACL_NFS4);
251 		else
252 			ret = pathconf(ent->fts_accpath, _PC_ACL_NFS4);
253 		if (ret > 0)
254 			supports_acls = 1;
255 		else if (ret < 0 && errno != EINVAL)
256 			warn("%s", ent->fts_path);
257 	}
258 
259 	return (supports_acls);
260 }
261