xref: /netbsd-src/usr.bin/chpass/chpass.c (revision d0fed6c87ddc40a8bffa6f99e7433ddfc864dd83)
1 /*	$NetBSD: chpass.c,v 1.11 1997/01/05 10:06:40 cjs Exp $	*/
2 
3 /*-
4  * Copyright (c) 1988, 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1988, 1993, 1994\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)chpass.c	8.4 (Berkeley) 4/2/94";
45 #else
46 static char rcsid[] = "$NetBSD: chpass.c,v 1.11 1997/01/05 10:06:40 cjs Exp $";
47 #endif
48 #endif /* not lint */
49 
50 #include <sys/param.h>
51 #include <sys/stat.h>
52 #include <sys/time.h>
53 #include <sys/resource.h>
54 
55 #include <ctype.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <pwd.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <unistd.h>
64 #include <util.h>
65 
66 #include "chpass.h"
67 #include "pathnames.h"
68 
69 extern	char *__progname;		/* from crt0.o */
70 
71 char *tempname;
72 uid_t uid;
73 int use_yp;
74 int yflag;
75 
76 void	(*Pw_error) __P((const char *, int, int));
77 
78 #ifdef	YP
79 extern struct passwd *ypgetpwnam(), *ypgetpwuid();
80 extern	int _yp_check __P((char **));	/* buried deep inside libc */
81 #endif
82 
83 void	baduser __P((void));
84 void	usage __P((void));
85 
86 int
87 main(argc, argv)
88 	int argc;
89 	char **argv;
90 {
91 	enum { NEWSH, LOADENTRY, EDITENTRY } op;
92 	struct passwd *pw, lpw;
93 	int ch, pfd, tfd, dfd;
94 	char *arg, *username = NULL, tempname[] = "/etc/pw.XXXXXX";
95 
96 #ifdef	YP
97 	use_yp = _yp_check(NULL);
98 #endif
99 
100 	op = EDITENTRY;
101 	while ((ch = getopt(argc, argv, "a:s:ly")) != EOF)
102 		switch(ch) {
103 		case 'a':
104 			op = LOADENTRY;
105 			arg = optarg;
106 			break;
107 		case 's':
108 			op = NEWSH;
109 			arg = optarg;
110 			break;
111 		case 'l':
112 			use_yp = 0;
113 			break;
114 		case 'y':
115 #ifdef	YP
116 			if (!use_yp)
117 				errx(1, "YP not in use.");
118 			yflag = 1;
119 #else
120 			errx(1, "YP support not compiled in.");
121 #endif
122 			break;
123 		default:
124 			usage();
125 		}
126 	argc -= optind;
127 	argv += optind;
128 
129 	uid = getuid();
130 	switch (argc) {
131 	case 0:
132 		/* nothing */
133 		break;
134 
135 	case 1:
136 		username = argv[0];
137 		break;
138 
139 	default:
140 		usage();
141 	}
142 
143 #ifdef YP
144 	/*
145 	 * We need to determine if we _really_ want to use YP.
146 	 * If we defaulted to YP (i.e. were not given the -y flag),
147 	 * and the master is not running rpc.yppasswdd, we check
148 	 * to see if the user exists in the local passwd database.
149 	 * If so, we use it, otherwise we error out.
150 	 */
151 	if (use_yp && yflag == 0) {
152 		if (check_yppasswdd()) {
153 			/*
154 			 * We weren't able to contact rpc.yppasswdd.
155 			 * Check to see if we're in the local
156 			 * password database.  If we are, use it.
157 			 */
158 			if (username != NULL)
159 				pw = getpwnam(username);
160 			else
161 				pw = getpwuid(uid);
162 			if (pw != NULL)
163 				use_yp = 0;
164 			else {
165 				errx(1, "master YP server not running yppasswd daemon.\n\t%s\n",
166 				    "Can't change password.");
167 			}
168 		}
169 	}
170 #endif
171 
172 #ifdef YP
173 	if (use_yp)
174 		Pw_error = yppw_error;
175 	else
176 #endif
177 		Pw_error = pw_error;
178 
179 #ifdef	YP
180 	if (op == LOADENTRY && use_yp)
181 		errx(1, "cannot load entry using YP.\n\tUse the -l flag to load local.");
182 #endif
183 
184 	if (op == EDITENTRY || op == NEWSH) {
185 		if (username != NULL) {
186 #ifdef YP
187 			if (use_yp)
188 				pw = ypgetpwnam(username);
189 			else
190 #endif /* YP */
191 				pw = getpwnam(username);
192 			if (pw == NULL)
193 				errx(1, "unknown user: %s", username);
194 			if (uid && uid != pw->pw_uid)
195 				baduser();
196 		} else {
197 #ifdef YP
198 			if (use_yp)
199 				pw = ypgetpwuid(uid);
200 			else
201 #endif /* YP */
202 				pw = getpwuid(uid);
203 			if (pw == NULL)
204 				errx(1, "unknown user: uid %u\n", uid);
205 		}
206 	}
207 
208 	if (op == NEWSH) {
209 		/* protect p_shell -- it thinks NULL is /bin/sh */
210 		if (!arg[0])
211 			usage();
212 		if (p_shell(arg, pw, (ENTRY *)NULL))
213 				(*Pw_error)((char *)NULL, 0, 1);
214 	}
215 
216 	if (op == LOADENTRY) {
217 		if (uid)
218 			baduser();
219 		pw = &lpw;
220 		if (!pw_scan(arg, pw, (int *)NULL))
221 			exit(1);
222 	}
223 
224 	if (!use_yp) {
225 		/*
226 		 * Get the passwd lock file and open the passwd file for
227 		 * reading.
228 		 */
229 		pw_init();
230 		tfd = pw_lock(0);
231 		if (tfd < 0)
232 			errx(1, "the passwd file is busy.");
233 		pfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
234 		if (pfd < 0)
235 			pw_error(_PATH_MASTERPASSWD, 1, 1);
236 	}
237 
238 	/* Edit the user passwd information if requested. */
239 	if (op == EDITENTRY) {
240 		dfd = mkstemp(tempname);
241 		if (dfd < 0) {
242 				(*Pw_error)(tempname, 1, 1);
243 		}
244 		display(tempname, dfd, pw);
245 		edit(tempname, pw);
246 		(void)unlink(tempname);
247 	}
248 
249 #ifdef	YP
250 	if (use_yp) {
251 		if (pw_yp(pw, uid))
252 			yppw_error((char *)NULL, 0, 1);
253 		else
254 			exit(0);
255 	}
256 	else
257 #endif	/* YP */
258 
259 	/* Copy the passwd file to the lock file, updating pw. */
260 	pw_copy(pfd, tfd, pw);
261 
262 	/* Now finish the passwd file update. */
263 	if (pw_mkdb() < 0)
264 		pw_error((char *)NULL, 0, 1);
265 
266 	exit(0);
267 }
268 
269 void
270 baduser()
271 {
272 
273 	errx(1, "%s", strerror(EACCES));
274 }
275 
276 void
277 usage()
278 {
279 
280 #ifdef	YP
281 	(void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [-l]%s [user]\n", use_yp?" [-y]":"");
282 #else
283 	(void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [user]\n");
284 #endif
285 	exit(1);
286 }
287