xref: /freebsd/lib/libutil/pw_util.c (revision 0640d357f29fb1c0daaaffadd0416c5981413afd)
1 /*-
2  * Copyright (c) 1990, 1993, 1994
3  *	The Regents of the University of California.  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 #if 0
36 static const char sccsid[] = "@(#)pw_util.c	8.3 (Berkeley) 4/2/94";
37 #endif
38 static const char rcsid[] =
39 	"$Id: pw_util.c,v 1.10 1998/10/13 14:52:33 des Exp $";
40 #endif /* not lint */
41 
42 /*
43  * This file is used by all the "password" programs; vipw(8), chpass(1),
44  * and passwd(1).
45  */
46 
47 #include <sys/param.h>
48 #include <sys/errno.h>
49 #include <sys/time.h>
50 #include <sys/resource.h>
51 #include <sys/stat.h>
52 #include <sys/wait.h>
53 
54 #include <err.h>
55 #include <fcntl.h>
56 #include <paths.h>
57 #include <pwd.h>
58 #include <signal.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 
64 #include "pw_util.h"
65 
66 extern char *tempname;
67 static pid_t editpid = -1;
68 static int lockfd;
69 
70 void
71 pw_cont(sig)
72 	int sig;
73 {
74 
75 	if (editpid != -1)
76 		kill(editpid, sig);
77 }
78 
79 void
80 pw_init()
81 {
82 	struct rlimit rlim;
83 
84 	/* Unlimited resource limits. */
85 	rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
86 	(void)setrlimit(RLIMIT_CPU, &rlim);
87 	(void)setrlimit(RLIMIT_FSIZE, &rlim);
88 	(void)setrlimit(RLIMIT_STACK, &rlim);
89 	(void)setrlimit(RLIMIT_DATA, &rlim);
90 	(void)setrlimit(RLIMIT_RSS, &rlim);
91 
92 	/* Don't drop core (not really necessary, but GP's). */
93 	rlim.rlim_cur = rlim.rlim_max = 0;
94 	(void)setrlimit(RLIMIT_CORE, &rlim);
95 
96 	/* Turn off signals. */
97 	(void)signal(SIGALRM, SIG_IGN);
98 	(void)signal(SIGHUP, SIG_IGN);
99 	(void)signal(SIGINT, SIG_IGN);
100 	(void)signal(SIGPIPE, SIG_IGN);
101 	(void)signal(SIGQUIT, SIG_IGN);
102 	(void)signal(SIGTERM, SIG_IGN);
103 	(void)signal(SIGCONT, pw_cont);
104 
105 	/* Create with exact permissions. */
106 	(void)umask(0);
107 }
108 
109 int
110 pw_lock()
111 {
112 	/*
113 	 * If the master password file doesn't exist, the system is hosed.
114 	 * Might as well try to build one.  Set the close-on-exec bit so
115 	 * that users can't get at the encrypted passwords while editing.
116 	 * Open should allow flock'ing the file; see 4.4BSD.	XXX
117 	 */
118 	lockfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
119 	if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
120 		err(1, "%s", _PATH_MASTERPASSWD);
121 	if (flock(lockfd, LOCK_EX|LOCK_NB))
122 		errx(1, "the password db file is busy");
123 	return (lockfd);
124 }
125 
126 int
127 pw_tmp()
128 {
129 	static char path[MAXPATHLEN] = _PATH_MASTERPASSWD;
130 	int fd;
131 	char *p;
132 
133 	if ((p = strrchr(path, '/')))
134 		++p;
135 	else
136 		p = path;
137 	strcpy(p, "pw.XXXXXX");
138 	if ((fd = mkstemp(path)) == -1)
139 		err(1, "%s", path);
140 	tempname = path;
141 	return (fd);
142 }
143 
144 int
145 pw_mkdb(username)
146 char *username;
147 {
148 	int pstat;
149 	pid_t pid;
150 
151 	(void)fflush(stderr);
152 	if (!(pid = fork())) {
153 		if(!username) {
154 			warnx("rebuilding the database...");
155 			execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", tempname, NULL);
156 		} else {
157 			warnx("updating the database...");
158 			execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", "-u",
159 					username, tempname, NULL);
160 		}
161 		pw_error(_PATH_PWD_MKDB, 1, 1);
162 	}
163 	pid = waitpid(pid, &pstat, 0);
164 	if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
165 		return (0);
166 	warnx("done");
167 	return (1);
168 }
169 
170 void
171 pw_edit(notsetuid)
172 	int notsetuid;
173 {
174 	int pstat;
175 	char *p, *editor;
176 
177 	if (!(editor = getenv("EDITOR")))
178 		editor = _PATH_VI;
179 	if ((p = strrchr(editor, '/')))
180 		++p;
181 	else
182 		p = editor;
183 
184 	if (!(editpid = fork())) {
185 		if (notsetuid) {
186 			(void)setgid(getgid());
187 			(void)setuid(getuid());
188 		}
189 		errno = 0;
190 		execlp(editor, p, tempname, NULL);
191 		_exit(errno);
192 	}
193 	for (;;) {
194 		editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
195 		errno = WEXITSTATUS(pstat);
196 		if (editpid == -1)
197 			pw_error(editor, 1, 1);
198 		else if (WIFSTOPPED(pstat))
199 			raise(WSTOPSIG(pstat));
200 		else if (WIFEXITED(pstat) && errno == 0)
201 			break;
202 		else
203 			pw_error(editor, 1, 1);
204 	}
205 	editpid = -1;
206 }
207 
208 void
209 pw_prompt()
210 {
211 	int c, first;
212 
213 	(void)printf("re-edit the password file? [y]: ");
214 	(void)fflush(stdout);
215 	first = c = getchar();
216 	while (c != '\n' && c != EOF)
217 		c = getchar();
218 	if (first == 'n')
219 		pw_error(NULL, 0, 0);
220 }
221 
222 void
223 pw_error(name, err, eval)
224 	char *name;
225 	int err, eval;
226 {
227 #ifdef YP
228 	extern int _use_yp;
229 #endif /* YP */
230 	if (err)
231 		warn(name);
232 #ifdef YP
233 	if (_use_yp)
234 		warnx("NIS information unchanged");
235 	else
236 #endif /* YP */
237 	warnx("%s: unchanged", _PATH_MASTERPASSWD);
238 	(void)unlink(tempname);
239 	exit(eval);
240 }
241