xref: /freebsd/usr.bin/lock/lock.c (revision 17ee9d00bc1ae1e598c38f25826f861e4bc6c3ce)
1 /*
2  * Copyright (c) 1980, 1987, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Bob Toxen.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static char copyright[] =
39 "@(#) Copyright (c) 1980, 1987, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 static char sccsid[] = "@(#)lock.c	8.1 (Berkeley) 6/6/93";
45 #endif /* not lint */
46 
47 /*
48  * Lock a terminal up until the given key is entered, until the root
49  * password is entered, or the given interval times out.
50  *
51  * Timeout interval is by default TIMEOUT, it can be changed with
52  * an argument of the form -time where time is in minutes
53  */
54 
55 #include <sys/param.h>
56 #include <sys/stat.h>
57 #include <sys/time.h>
58 #include <sys/signal.h>
59 #include <sgtty.h>
60 #include <pwd.h>
61 #include <stdio.h>
62 #include <ctype.h>
63 #include <string.h>
64 
65 #define	TIMEOUT	15
66 
67 void quit(), bye(), hi();
68 
69 struct timeval	timeout;
70 struct timeval	zerotime;
71 struct sgttyb	tty, ntty;
72 long	nexttime;			/* keep the timeout time */
73 
74 /*ARGSUSED*/
75 main(argc, argv)
76 	int argc;
77 	char **argv;
78 {
79 	extern char *optarg;
80 	extern int errno, optind;
81 	struct passwd *pw;
82 	struct timeval timval;
83 	struct itimerval ntimer, otimer;
84 	struct tm *timp;
85 	int ch, sectimeout, usemine;
86 	char *ap, *mypw, *ttynam, *tzn;
87 	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
88 	char *crypt(), *ttyname();
89 
90 	sectimeout = TIMEOUT;
91 	mypw = NULL;
92 	usemine = 0;
93 	while ((ch = getopt(argc, argv, "pt:")) != EOF)
94 		switch((char)ch) {
95 		case 't':
96 			if ((sectimeout = atoi(optarg)) <= 0) {
97 				(void)fprintf(stderr,
98 				    "lock: illegal timeout value.\n");
99 				exit(1);
100 			}
101 			break;
102 		case 'p':
103 			usemine = 1;
104 			if (!(pw = getpwuid(getuid()))) {
105 				(void)fprintf(stderr,
106 				    "lock: unknown uid %d.\n", getuid());
107 				exit(1);
108 			}
109 			mypw = strdup(pw->pw_passwd);
110 			break;
111 		case '?':
112 		default:
113 			(void)fprintf(stderr,
114 			    "usage: lock [-p] [-t timeout]\n");
115 			exit(1);
116 	}
117 	timeout.tv_sec = sectimeout * 60;
118 
119 	setuid(getuid());		/* discard privs */
120 
121 	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
122 		exit(1);
123 	gethostname(hostname, sizeof(hostname));
124 	if (!(ttynam = ttyname(0))) {
125 		(void)printf("lock: not a terminal?\n");
126 		exit(1);
127 	}
128 	if (gettimeofday(&timval, (struct timezone *)NULL)) {
129 		(void)fprintf(stderr,
130 		    "lock: gettimeofday: %s\n", strerror(errno));
131 		exit(1);
132 	}
133 	nexttime = timval.tv_sec + (sectimeout * 60);
134 	timp = localtime(&timval.tv_sec);
135 	ap = asctime(timp);
136 	tzn = timp->tm_zone;
137 
138 	(void)signal(SIGINT, quit);
139 	(void)signal(SIGQUIT, quit);
140 	ntty = tty; ntty.sg_flags &= ~ECHO;
141 	(void)ioctl(0, TIOCSETP, &ntty);
142 
143 	if (!mypw) {
144 		/* get key and check again */
145 		(void)printf("Key: ");
146 		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
147 			quit();
148 		(void)printf("\nAgain: ");
149 		/*
150 		 * Don't need EOF test here, if we get EOF, then s1 != s
151 		 * and the right things will happen.
152 		 */
153 		(void)fgets(s1, sizeof(s1), stdin);
154 		(void)putchar('\n');
155 		if (strcmp(s1, s)) {
156 			(void)printf("\07lock: passwords didn't match.\n");
157 			ioctl(0, TIOCSETP, &tty);
158 			exit(1);
159 		}
160 		s[0] = NULL;
161 		mypw = s1;
162 	}
163 
164 	/* set signal handlers */
165 	(void)signal(SIGINT, hi);
166 	(void)signal(SIGQUIT, hi);
167 	(void)signal(SIGTSTP, hi);
168 	(void)signal(SIGALRM, bye);
169 
170 	ntimer.it_interval = zerotime;
171 	ntimer.it_value = timeout;
172 	setitimer(ITIMER_REAL, &ntimer, &otimer);
173 
174 	/* header info */
175 (void)printf("lock: %s on %s. timeout in %d minutes\ntime now is %.20s%s%s",
176 	    ttynam, hostname, sectimeout, ap, tzn, ap + 19);
177 
178 	for (;;) {
179 		(void)printf("Key: ");
180 		if (!fgets(s, sizeof(s), stdin)) {
181 			clearerr(stdin);
182 			hi();
183 			continue;
184 		}
185 		if (usemine) {
186 			s[strlen(s) - 1] = '\0';
187 			if (!strcmp(mypw, crypt(s, mypw)))
188 				break;
189 		}
190 		else if (!strcmp(s, s1))
191 			break;
192 		(void)printf("\07\n");
193 		if (ioctl(0, TIOCGETP, &ntty))
194 			exit(1);
195 	}
196 	quit();
197 }
198 
199 void
200 hi()
201 {
202 	struct timeval timval;
203 
204 	if (!gettimeofday(&timval, (struct timezone *)NULL))
205 (void)printf("lock: type in the unlock key. timeout in %ld:%ld minutes\n",
206 	    (nexttime - timval.tv_sec) / 60, (nexttime - timval.tv_sec) % 60);
207 }
208 
209 void
210 quit()
211 {
212 	(void)putchar('\n');
213 	(void)ioctl(0, TIOCSETP, &tty);
214 	exit(0);
215 }
216 
217 void
218 bye()
219 {
220 	(void)ioctl(0, TIOCSETP, &tty);
221 	(void)printf("lock: timeout\n");
222 	exit(1);
223 }
224