chpass.c revision 1.4.2.2 1 /*-
2 * Copyright (c) 1988 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #ifndef lint
35 char copyright[] =
36 "@(#) Copyright (c) 1988 The Regents of the University of California.\n\
37 All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)chpass.c 5.17 (Berkeley) 3/3/91";*/
42 static char rcsid[] = "$Id: chpass.c,v 1.4.2.2 1994/08/17 19:54:40 deraadt Exp $";
43 #endif /* not lint */
44
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/signal.h>
48 #include <sys/time.h>
49 #include <sys/resource.h>
50 #include <fcntl.h>
51 #include <pwd.h>
52 #include <errno.h>
53 #include <stdio.h>
54 #include <ctype.h>
55 #include <string.h>
56 #include "chpass.h"
57 #include "pathnames.h"
58
59 char *progname = "chpass";
60 char *tempname;
61 uid_t uid;
62
63 #ifdef YP
64 int use_yp;
65 int force_yp = 0;
66 extern struct passwd *ypgetpwnam(), *ypgetpwuid();
67 #endif
68
69 main(argc, argv)
70 int argc;
71 char **argv;
72 {
73 extern int optind;
74 extern char *optarg;
75 register enum { NEWSH, LOADENTRY, EDITENTRY } op;
76 register struct passwd *pw;
77 struct passwd lpw;
78 int ch, pfd, tfd;
79 char *arg;
80
81 #ifdef YP
82 use_yp = _yp_check(NULL);
83 #endif
84
85 op = EDITENTRY;
86 while ((ch = getopt(argc, argv, "a:s:ly")) != EOF)
87 switch(ch) {
88 case 'a':
89 op = LOADENTRY;
90 arg = optarg;
91 break;
92 case 's':
93 op = NEWSH;
94 arg = optarg;
95 break;
96 #ifdef YP
97 case 'l':
98 use_yp = 0;
99 break;
100 case 'y':
101 if (!use_yp) {
102 fprintf(stderr, "chpass: YP not in use.\n");
103 usage();
104 exit(1);
105 }
106 force_yp = 1;
107 break;
108 #endif
109 case '?':
110 default:
111 usage();
112 }
113 argc -= optind;
114 argv += optind;
115
116 #ifdef YP
117 if (op == LOADENTRY && use_yp) {
118 (void)fprintf(stderr, "chpass: cannot load entry using NIS.\n\tUse the -l flag to load local.\n");
119 exit(1);
120 }
121 #endif
122 uid = getuid();
123
124 if (op == EDITENTRY || op == NEWSH)
125 switch(argc) {
126 case 0:
127 pw = getpwuid(uid);
128 #ifdef YP
129 if (pw && !force_yp)
130 use_yp = 0;
131 else if (use_yp)
132 pw = ypgetpwuid(uid);
133 #endif /* YP */
134 if (!pw) {
135 (void)fprintf(stderr,
136 "chpass: unknown user: uid %u\n", uid);
137 exit(1);
138 }
139 break;
140 case 1:
141 pw = getpwnam(*argv);
142 #ifdef YP
143 if (pw && !force_yp)
144 use_yp = 0;
145 else if (use_yp)
146 pw = ypgetpwnam(*argv);
147 #endif /* YP */
148 if (!pw) {
149 (void)fprintf(stderr,
150 "chpass: unknown user %s.\n", *argv);
151 exit(1);
152 }
153 if (uid && uid != pw->pw_uid)
154 baduser();
155 break;
156 default:
157 usage();
158 }
159
160 if (op == NEWSH) {
161 /* protect p_shell -- it thinks NULL is /bin/sh */
162 if (!arg[0])
163 usage();
164 if (p_shell(arg, pw, (ENTRY *)NULL))
165 pw_error((char *)NULL, 0, 1);
166 }
167
168 if (op == LOADENTRY) {
169 if (uid)
170 baduser();
171 pw = &lpw;
172 if (!pw_scan(arg, pw))
173 exit(1);
174 }
175
176 /*
177 * The temporary file/file descriptor usage is a little tricky here.
178 * 1: We start off with two fd's, one for the master password
179 * file (used to lock everything), and one for a temporary file.
180 * 2: Display() gets an fp for the temporary file, and copies the
181 * user's information into it. It then gives the temporary file
182 * to the user and closes the fp, closing the underlying fd.
183 * 3: The user edits the temporary file some number of times.
184 * 4: Verify() gets an fp for the temporary file, and verifies the
185 * contents. It can't use an fp derived from the step #2 fd,
186 * because the user's editor may have created a new instance of
187 * the file. Once the file is verified, its contents are stored
188 * in a password structure. The verify routine closes the fp,
189 * closing the underlying fd.
190 * 5: Delete the temporary file.
191 * 6: Get a new temporary file/fd. Pw_copy() gets an fp for it
192 * file and copies the master password file into it, replacing
193 * the user record with a new one. We can't use the first
194 * temporary file for this because it was owned by the user.
195 * Pw_copy() closes its fp, flushing the data and closing the
196 * underlying file descriptor. We can't close the master
197 * password fp, or we'd lose the lock.
198 * 7: Call pw_mkdb() (which renames the temporary file) and exit.
199 * The exit closes the master passwd fp/fd.
200 */
201 pw_init();
202 pfd = pw_lock();
203 tfd = pw_tmp();
204
205 if (op == EDITENTRY) {
206 display(tfd, pw);
207 edit(pw);
208 (void)unlink(tempname);
209 tfd = pw_tmp();
210 }
211
212 #ifdef YP
213 if (use_yp) {
214 (void)unlink(tempname);
215 if (pw_yp(pw, uid))
216 pw_error((char *)NULL, 0, 1);
217 else
218 exit(0);
219 }
220 else
221 #endif /* YP */
222 pw_copy(pfd, tfd, pw);
223
224 if (!pw_mkdb())
225 pw_error((char *)NULL, 0, 1);
226
227 exit(0);
228 }
229
230 baduser()
231 {
232 (void)fprintf(stderr, "chpass: %s\n", strerror(EACCES));
233 exit(1);
234 }
235
236 usage()
237 {
238 #ifdef YP
239 (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [-l]%s [user]\n", use_yp?" [-y]":"");
240 #else
241 (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [user]\n");
242 #endif
243 exit(1);
244 }
245