xref: /netbsd-src/sbin/chown/chown.c (revision b7424e7c5d8f503c3538bedf3fdd9504ff73907f)
1 /*	$NetBSD: chown.c,v 1.12 2023/05/04 18:34:55 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993, 1994, 2003
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 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994, 2003\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)chown.c	8.8 (Berkeley) 4/4/94";
41 #else
42 __RCSID("$NetBSD: chown.c,v 1.12 2023/05/04 18:34:55 christos Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #include <sys/types.h>
47 #include <sys/stat.h>
48 
49 #include <ctype.h>
50 #include <dirent.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <locale.h>
54 #include <fts.h>
55 #include <grp.h>
56 #include <pwd.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61 #include <getopt.h>
62 
63 static void	a_gid(const char *);
64 static void	a_uid(const char *);
65 static id_t	id(const char *, const char *);
66 __dead static void	usage(void);
67 
68 static uid_t uid;
69 static gid_t gid;
70 static int ischown;
71 static const char *myname;
72 
73 struct option chown_longopts[] = {
74 	{ "reference",		required_argument,	0,
75 						1 },
76 	{ NULL,			0,			0,
77 						0 },
78 };
79 
80 int
main(int argc,char ** argv)81 main(int argc, char **argv)
82 {
83 	FTS *ftsp;
84 	FTSENT *p;
85 	int Hflag, Lflag, Rflag, ch, fflag, fts_options, hflag, rval, vflag, dflag;
86 	char *cp, *reference;
87 	int (*change_owner)(const char *, uid_t, gid_t);
88 
89 	setprogname(*argv);
90 
91 	(void)setlocale(LC_ALL, "");
92 
93 	myname = getprogname();
94 	ischown = (myname[2] == 'o');
95 	reference = NULL;
96 
97 	Hflag = Lflag = Rflag = fflag = hflag = vflag = dflag = 0;
98 	while ((ch = getopt_long(argc, argv, "HLPRdfhv",
99 	    chown_longopts, NULL)) != -1)
100 		switch (ch) {
101 		case 1:
102 			reference = optarg;
103 			break;
104 		case 'd':
105 			dflag = 1;
106 			break;
107 		case 'H':
108 			Hflag = 1;
109 			Lflag = 0;
110 			break;
111 		case 'L':
112 			Lflag = 1;
113 			Hflag = 0;
114 			break;
115 		case 'P':
116 			Hflag = Lflag = 0;
117 			break;
118 		case 'R':
119 			Rflag = 1;
120 			break;
121 		case 'f':
122 			fflag = 1;
123 			break;
124 		case 'h':
125 			/*
126 			 * In System V the -h option causes chown/chgrp to
127 			 * change the owner/group of the symbolic link.
128 			 * 4.4BSD's symbolic links didn't have owners/groups,
129 			 * so it was an undocumented noop.
130 			 * In NetBSD 1.3, lchown(2) is introduced.
131 			 */
132 			hflag = 1;
133 			break;
134 		case 'v':
135 			vflag = 1;
136 			break;
137 		case '?':
138 		default:
139 			usage();
140 		}
141 	argv += optind;
142 	argc -= optind;
143 
144 	if (argc == 0 || (argc == 1 && reference == NULL))
145 		usage();
146 
147 	fts_options = FTS_PHYSICAL;
148 	if (Rflag) {
149 		if (Hflag)
150 			fts_options |= FTS_COMFOLLOW;
151 		if (Lflag) {
152 			if (hflag)
153 				errx(EXIT_FAILURE,
154 				    "the -L and -h options "
155 				    "may not be specified together.");
156 			fts_options &= ~FTS_PHYSICAL;
157 			fts_options |= FTS_LOGICAL;
158 		}
159 	} else if (!hflag)
160 		fts_options |= FTS_COMFOLLOW;
161 
162 	uid = (uid_t)-1;
163 	gid = (gid_t)-1;
164 	if (reference == NULL) {
165 		if (ischown) {
166 			if ((cp = strchr(*argv, ':')) != NULL) {
167 				*cp++ = '\0';
168 				a_gid(cp);
169 			}
170 #ifdef SUPPORT_DOT
171 			else if ((cp = strrchr(*argv, '.')) != NULL) {
172 				if (uid_from_user(*argv, &uid) == -1) {
173 					*cp++ = '\0';
174 					a_gid(cp);
175 				}
176 			}
177 #endif
178 			a_uid(*argv);
179 		} else
180 			a_gid(*argv);
181 		argv++;
182 	} else {
183 		struct stat st;
184 
185 		if (stat(reference, &st) == -1)
186 			err(EXIT_FAILURE, "Cannot stat `%s'", reference);
187 		if (ischown)
188 			uid = st.st_uid;
189 		gid = st.st_gid;
190 	}
191 
192 	if ((ftsp = fts_open(argv, fts_options, NULL)) == NULL)
193 		err(EXIT_FAILURE, "fts_open");
194 
195 	for (rval = EXIT_SUCCESS; (p = fts_read(ftsp)) != NULL;) {
196 		change_owner = chown;
197 		switch (p->fts_info) {
198 		case FTS_D:
199 			if (!Rflag)		/* Change it at FTS_DP. */
200 				fts_set(ftsp, p, FTS_SKIP);
201 			continue;
202 		case FTS_DNR:			/* Warn, chown, continue. */
203 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
204 			rval = EXIT_FAILURE;
205 			break;
206 		case FTS_ERR:			/* Warn, continue. */
207 		case FTS_NS:
208 			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
209 			rval = EXIT_FAILURE;
210 			continue;
211 		case FTS_SL:			/* Ignore unless -h. */
212 			/*
213 			 * All symlinks we found while doing a physical
214 			 * walk end up here.
215 			 */
216 			if (!hflag)
217 				continue;
218 			/*
219 			 * Note that if we follow a symlink, fts_info is
220 			 * not FTS_SL but FTS_F or whatever.  And we should
221 			 * use lchown only for FTS_SL and should use chown
222 			 * for others.
223 			 */
224 			change_owner = lchown;
225 			break;
226 		case FTS_SLNONE:		/* Ignore. */
227 			/*
228 			 * The only symlinks that end up here are ones that
229 			 * don't point to anything.  Note that if we are
230 			 * doing a physical walk, we never reach here unless
231 			 * we asked to follow explicitly.
232 			 */
233 			continue;
234 		default:
235 			break;
236 		}
237 
238 		/*
239 		 * If dflag was set, and the owner and group are already
240 		 * set to the right values and the set-user-id and
241 		 * set-group-id bits are both already clear, skip any
242 		 * attempt to update.
243 		 */
244 		if (dflag &&
245 		    (uid == (uid_t)-1 || p->fts_statp->st_uid == uid) &&
246 		    (gid == (gid_t)-1 || p->fts_statp->st_gid == gid) &&
247 		    (p->fts_statp->st_mode & 07000) == 0)
248 			continue;
249 
250 		if ((*change_owner)(p->fts_accpath, uid, gid) && !fflag) {
251 			warn("%s", p->fts_path);
252 			rval = EXIT_FAILURE;
253 		} else {
254 			if (vflag)
255 				printf("%s\n", p->fts_path);
256 		}
257 	}
258 	if (errno)
259 		err(EXIT_FAILURE, "fts_read");
260 	exit(rval);
261 	/* NOTREACHED */
262 }
263 
264 static void
a_gid(const char * s)265 a_gid(const char *s)
266 {
267 	struct group *gr;
268 
269 	if (*s == '\0')			/* Argument was "uid[:.]". */
270 		return;
271 	gr = *s == '#' ? NULL : getgrnam(s);
272 	if (gr == NULL)
273 		gid = id(s, "group");
274 	else
275 		gid = gr->gr_gid;
276 	return;
277 }
278 
279 static void
a_uid(const char * s)280 a_uid(const char *s)
281 {
282 	if (*s == '\0')			/* Argument was "[:.]gid". */
283 		return;
284 	if (*s == '#' || uid_from_user(s, &uid) == -1) {
285 		uid = id(s, "user");
286 	}
287 	return;
288 }
289 
290 static id_t
id(const char * name,const char * type)291 id(const char *name, const char *type)
292 {
293 	id_t val;
294 	char *ep;
295 
296 	errno = 0;
297 	if (*name == '#')
298 		name++;
299 	val = (id_t)strtoul(name, &ep, 10);
300 	if (errno)
301 		err(EXIT_FAILURE, "%s", name);
302 	if (*ep != '\0')
303 		errx(EXIT_FAILURE, "%s: invalid %s name", name, type);
304 	return (val);
305 }
306 
307 static void
usage(void)308 usage(void)
309 {
310 
311 	(void)fprintf(stderr,
312 	    "Usage: %s [-R [-H | -L | -P]] [-dfhv] %s file ...\n"
313 	    "\t%s [-R [-H | -L | -P]] [-dfhv] --reference=rfile file ...\n",
314 	    myname, ischown ? "owner:group|owner|:group" : "group",
315 	    myname);
316 	exit(EXIT_FAILURE);
317 }
318