xref: /freebsd/lib/libutil/pw_util.c (revision 8e6b01171e30297084bb0b4457c4183c2746aacc)
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 static char sccsid[] = "@(#)pw_util.c	8.3 (Berkeley) 4/2/94";
36 #endif /* not lint */
37 
38 /*
39  * This file is used by all the "password" programs; vipw(8), chpass(1),
40  * and passwd(1).
41  */
42 
43 #include <sys/param.h>
44 #include <sys/time.h>
45 #include <sys/resource.h>
46 #include <sys/stat.h>
47 #include <sys/wait.h>
48 
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <paths.h>
53 #include <pwd.h>
54 #include <signal.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 #include "pw_util.h"
61 
62 extern char *tempname;
63 static pid_t editpid = -1;
64 static int lockfd;
65 
66 void
67 pw_cont(sig)
68 	int sig;
69 {
70 
71 	if (editpid != -1)
72 		kill(editpid, sig);
73 }
74 
75 void
76 pw_init()
77 {
78 	struct rlimit rlim;
79 
80 	/* Unlimited resource limits. */
81 	rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
82 	(void)setrlimit(RLIMIT_CPU, &rlim);
83 	(void)setrlimit(RLIMIT_FSIZE, &rlim);
84 	(void)setrlimit(RLIMIT_STACK, &rlim);
85 	(void)setrlimit(RLIMIT_DATA, &rlim);
86 	(void)setrlimit(RLIMIT_RSS, &rlim);
87 
88 	/* Don't drop core (not really necessary, but GP's). */
89 	rlim.rlim_cur = rlim.rlim_max = 0;
90 	(void)setrlimit(RLIMIT_CORE, &rlim);
91 
92 	/* Turn off signals. */
93 	(void)signal(SIGALRM, SIG_IGN);
94 	(void)signal(SIGHUP, SIG_IGN);
95 	(void)signal(SIGINT, SIG_IGN);
96 	(void)signal(SIGPIPE, SIG_IGN);
97 	(void)signal(SIGQUIT, SIG_IGN);
98 	(void)signal(SIGTERM, SIG_IGN);
99 	(void)signal(SIGCONT, pw_cont);
100 
101 	/* Create with exact permissions. */
102 	(void)umask(0);
103 }
104 
105 int
106 pw_lock()
107 {
108 	/*
109 	 * If the master password file doesn't exist, the system is hosed.
110 	 * Might as well try to build one.  Set the close-on-exec bit so
111 	 * that users can't get at the encrypted passwords while editing.
112 	 * Open should allow flock'ing the file; see 4.4BSD.	XXX
113 	 */
114 	lockfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
115 	if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
116 		err(1, "%s", _PATH_MASTERPASSWD);
117 	if (flock(lockfd, LOCK_EX|LOCK_NB))
118 		errx(1, "the password db file is busy");
119 	return (lockfd);
120 }
121 
122 int
123 pw_tmp()
124 {
125 	static char path[MAXPATHLEN] = _PATH_MASTERPASSWD;
126 	int fd;
127 	char *p;
128 
129 	if (p = strrchr(path, '/'))
130 		++p;
131 	else
132 		p = path;
133 	strcpy(p, "pw.XXXXXX");
134 	if ((fd = mkstemp(path)) == -1)
135 		err(1, "%s", path);
136 	tempname = path;
137 	return (fd);
138 }
139 
140 int
141 pw_mkdb()
142 {
143 	int pstat;
144 	pid_t pid;
145 
146 	warnx("rebuilding the database...");
147 	(void)fflush(stderr);
148 	if (!(pid = vfork())) {
149 		execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", tempname, NULL);
150 		pw_error(_PATH_PWD_MKDB, 1, 1);
151 	}
152 	pid = waitpid(pid, &pstat, 0);
153 	if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
154 		return (0);
155 	warnx("done");
156 	return (1);
157 }
158 
159 void
160 pw_edit(notsetuid)
161 	int notsetuid;
162 {
163 	int pstat;
164 	char *p, *editor;
165 
166 	if (!(editor = getenv("EDITOR")))
167 		editor = _PATH_VI;
168 	if (p = strrchr(editor, '/'))
169 		++p;
170 	else
171 		p = editor;
172 
173 	if (!(editpid = vfork())) {
174 		if (notsetuid) {
175 			(void)setgid(getgid());
176 			(void)setuid(getuid());
177 		}
178 		execlp(editor, p, tempname, NULL);
179 		_exit(1);
180 	}
181 	for (;;) {
182 		editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
183 		if (editpid == -1)
184 			pw_error(editor, 1, 1);
185 		else if (WIFSTOPPED(pstat))
186 			raise(WSTOPSIG(pstat));
187 		else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0)
188 			break;
189 		else
190 			pw_error(editor, 1, 1);
191 	}
192 	editpid = -1;
193 }
194 
195 void
196 pw_prompt()
197 {
198 	int c;
199 
200 	(void)printf("re-edit the password file? [y]: ");
201 	(void)fflush(stdout);
202 	c = getchar();
203 	if (c != EOF && c != '\n')
204 		while (getchar() != '\n');
205 	if (c == 'n')
206 		pw_error(NULL, 0, 0);
207 }
208 
209 void
210 pw_error(name, err, eval)
211 	char *name;
212 	int err, eval;
213 {
214 #ifdef YP
215 	extern int _use_yp;
216 #endif /* YP */
217 	if (err)
218 		warn(name);
219 #ifdef YP
220 	if (_use_yp)
221 		warnx("NIS information unchanged");
222 	else
223 #endif /* YP */
224 	warnx("%s: unchanged", _PATH_MASTERPASSWD);
225 	(void)unlink(tempname);
226 	exit(eval);
227 }
228