xref: /freebsd/bin/chmod/chmod.c (revision 19fae0f66023a97a9b464b3beeeabb2081f575b3)
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 __FBSDID("$FreeBSD$");
45 
46 #include <sys/param.h>
47 #include <sys/stat.h>
48 
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <fts.h>
53 #include <limits.h>
54 #include <signal.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 static volatile sig_atomic_t siginfo;
61 
62 static void usage(void) __dead2;
63 static int may_have_nfs4acl(const FTSENT *ent, int hflag);
64 
65 static void
66 siginfo_handler(int sig __unused)
67 {
68 
69 	siginfo = 1;
70 }
71 
72 int
73 main(int argc, char *argv[])
74 {
75 	FTS *ftsp;
76 	FTSENT *p;
77 	mode_t *set;
78 	int Hflag, Lflag, Rflag, ch, fflag, fts_options, hflag, rval;
79 	int vflag;
80 	char *mode;
81 	mode_t newmode;
82 
83 	set = NULL;
84 	Hflag = Lflag = Rflag = fflag = hflag = vflag = 0;
85 	while ((ch = getopt(argc, argv, "HLPRXfghorstuvwx")) != -1)
86 		switch (ch) {
87 		case 'H':
88 			Hflag = 1;
89 			Lflag = 0;
90 			break;
91 		case 'L':
92 			Lflag = 1;
93 			Hflag = 0;
94 			break;
95 		case 'P':
96 			Hflag = Lflag = 0;
97 			break;
98 		case 'R':
99 			Rflag = 1;
100 			break;
101 		case 'f':
102 			fflag = 1;
103 			break;
104 		case 'h':
105 			/*
106 			 * In System V the -h option causes chmod to change
107 			 * the mode of the symbolic link. 4.4BSD's symbolic
108 			 * links didn't have modes, so it was an undocumented
109 			 * noop.  In FreeBSD 3.0, lchmod(2) is introduced and
110 			 * this option does real work.
111 			 */
112 			hflag = 1;
113 			break;
114 		/*
115 		 * XXX
116 		 * "-[rwx]" are valid mode commands.  If they are the entire
117 		 * argument, getopt has moved past them, so decrement optind.
118 		 * Regardless, we're done argument processing.
119 		 */
120 		case 'g': case 'o': case 'r': case 's':
121 		case 't': case 'u': case 'w': case 'X': case 'x':
122 			if (argv[optind - 1][0] == '-' &&
123 			    argv[optind - 1][1] == ch &&
124 			    argv[optind - 1][2] == '\0')
125 				--optind;
126 			goto done;
127 		case 'v':
128 			vflag++;
129 			break;
130 		case '?':
131 		default:
132 			usage();
133 		}
134 done:	argv += optind;
135 	argc -= optind;
136 
137 	if (argc < 2)
138 		usage();
139 
140 	(void)signal(SIGINFO, siginfo_handler);
141 
142 	if (Rflag) {
143 		if (hflag)
144 			errx(1, "the -R and -h options may not be "
145 			    "specified together.");
146 		if (Lflag) {
147 			fts_options = FTS_LOGICAL;
148 		} else {
149 			fts_options = FTS_PHYSICAL;
150 
151 			if (Hflag) {
152 				fts_options |= FTS_COMFOLLOW;
153 			}
154 		}
155 	} else if (hflag) {
156 		fts_options = FTS_PHYSICAL;
157 	} else {
158 		fts_options = FTS_LOGICAL;
159 	}
160 
161 	mode = *argv;
162 	if ((set = setmode(mode)) == NULL)
163 		errx(1, "invalid file mode: %s", mode);
164 
165 	if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
166 		err(1, "fts_open");
167 	for (rval = 0; errno = 0, (p = fts_read(ftsp)) != NULL;) {
168 		int atflag;
169 
170 		if ((fts_options & FTS_LOGICAL) ||
171 		    ((fts_options & FTS_COMFOLLOW) &&
172 		    p->fts_level == FTS_ROOTLEVEL))
173 			atflag = 0;
174 		else
175 			atflag = AT_SYMLINK_NOFOLLOW;
176 
177 		switch (p->fts_info) {
178 		case FTS_D:
179 			if (!Rflag)
180 				fts_set(ftsp, p, FTS_SKIP);
181 			break;
182 		case FTS_DNR:			/* Warn, chmod. */
183 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
184 			rval = 1;
185 			break;
186 		case FTS_DP:			/* Already changed at FTS_D. */
187 			continue;
188 		case FTS_ERR:			/* Warn, continue. */
189 		case FTS_NS:
190 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
191 			rval = 1;
192 			continue;
193 		default:
194 			break;
195 		}
196 		newmode = getmode(set, p->fts_statp->st_mode);
197 		/*
198 		 * With NFSv4 ACLs, it is possible that applying a mode
199 		 * identical to the one computed from an ACL will change
200 		 * that ACL.
201 		 */
202 		if (may_have_nfs4acl(p, hflag) == 0 &&
203 		    (newmode & ALLPERMS) == (p->fts_statp->st_mode & ALLPERMS))
204 				continue;
205 		if (fchmodat(AT_FDCWD, p->fts_accpath, newmode, atflag) == -1
206 		    && !fflag) {
207 			warn("%s", p->fts_path);
208 			rval = 1;
209 		} else if (vflag || siginfo) {
210 			(void)printf("%s", p->fts_path);
211 
212 			if (vflag > 1 || siginfo) {
213 				char m1[12], m2[12];
214 
215 				strmode(p->fts_statp->st_mode, m1);
216 				strmode((p->fts_statp->st_mode &
217 				    S_IFMT) | newmode, m2);
218 				(void)printf(": 0%o [%s] -> 0%o [%s]",
219 				    p->fts_statp->st_mode, m1,
220 				    (p->fts_statp->st_mode & S_IFMT) |
221 				    newmode, m2);
222 			}
223 			(void)printf("\n");
224 			siginfo = 0;
225 		}
226 	}
227 	if (errno)
228 		err(1, "fts_read");
229 	exit(rval);
230 }
231 
232 static void
233 usage(void)
234 {
235 	(void)fprintf(stderr,
236 	    "usage: chmod [-fhv] [-R [-H | -L | -P]] mode file ...\n");
237 	exit(1);
238 }
239 
240 static int
241 may_have_nfs4acl(const FTSENT *ent, int hflag)
242 {
243 	int ret;
244 	static dev_t previous_dev = NODEV;
245 	static int supports_acls = -1;
246 
247 	if (previous_dev != ent->fts_statp->st_dev) {
248 		previous_dev = ent->fts_statp->st_dev;
249 		supports_acls = 0;
250 
251 		if (hflag)
252 			ret = lpathconf(ent->fts_accpath, _PC_ACL_NFS4);
253 		else
254 			ret = pathconf(ent->fts_accpath, _PC_ACL_NFS4);
255 		if (ret > 0)
256 			supports_acls = 1;
257 		else if (ret < 0 && errno != EINVAL)
258 			warn("%s", ent->fts_path);
259 	}
260 
261 	return (supports_acls);
262 }
263