xref: /freebsd/usr.bin/lock/lock.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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 const 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 #if 0
45 static char sccsid[] = "@(#)lock.c	8.1 (Berkeley) 6/6/93";
46 #endif
47 static const char rcsid[] =
48 	"$Id: lock.c,v 1.4 1997/07/21 12:09:34 charnier Exp $";
49 #endif /* not lint */
50 
51 /*
52  * Lock a terminal up until the given key is entered, until the root
53  * password is entered, or the given interval times out.
54  *
55  * Timeout interval is by default TIMEOUT, it can be changed with
56  * an argument of the form -time where time is in minutes
57  */
58 
59 #include <sys/param.h>
60 #include <sys/stat.h>
61 #include <sys/time.h>
62 #include <sys/signal.h>
63 #include <err.h>
64 #include <ctype.h>
65 #include <pwd.h>
66 #include <sgtty.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <string.h>
70 #include <unistd.h>
71 
72 #define	TIMEOUT	15
73 
74 void quit(), bye(), hi();
75 static void usage __P((void));
76 
77 struct timeval	timeout;
78 struct timeval	zerotime;
79 struct sgttyb	tty, ntty;
80 long	nexttime;			/* keep the timeout time */
81 int            no_timeout;                     /* lock terminal forever */
82 
83 /*ARGSUSED*/
84 int
85 main(argc, argv)
86 	int argc;
87 	char **argv;
88 {
89 	struct passwd *pw;
90 	struct timeval timval;
91 	time_t timval_sec;
92 	struct itimerval ntimer, otimer;
93 	struct tm *timp;
94 	int ch, sectimeout, usemine;
95 	char *ap, *mypw, *ttynam, *tzn;
96 	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
97 	char *crypt(), *ttyname();
98 
99 	sectimeout = TIMEOUT;
100 	mypw = NULL;
101 	usemine = 0;
102        no_timeout = 0;
103        while ((ch = getopt(argc, argv, "npt:")) != -1)
104 		switch((char)ch) {
105 		case 't':
106 			if ((sectimeout = atoi(optarg)) <= 0)
107 				errx(1, "illegal timeout value");
108 			break;
109 		case 'p':
110 			usemine = 1;
111 			if (!(pw = getpwuid(getuid())))
112 				errx(1, "unknown uid %d", getuid());
113 			mypw = strdup(pw->pw_passwd);
114 			break;
115                case 'n':
116                        no_timeout = 1;
117                        break;
118 		case '?':
119 		default:
120 			usage();
121 	}
122 	timeout.tv_sec = sectimeout * 60;
123 
124 	setuid(getuid());		/* discard privs */
125 
126 	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
127 		exit(1);
128 	gethostname(hostname, sizeof(hostname));
129 	if (!(ttynam = ttyname(0)))
130 		errx(1, "not a terminal?");
131 	if (gettimeofday(&timval, (struct timezone *)NULL))
132 		err(1, "gettimeofday");
133 	nexttime = timval.tv_sec + (sectimeout * 60);
134 	timval_sec = timval.tv_sec;
135 	timp = localtime(&timval_sec);
136 	ap = asctime(timp);
137 	tzn = timp->tm_zone;
138 
139 	(void)signal(SIGINT, quit);
140 	(void)signal(SIGQUIT, quit);
141 	ntty = tty; ntty.sg_flags &= ~ECHO;
142 	(void)ioctl(0, TIOCSETP, &ntty);
143 
144 	if (!mypw) {
145 		/* get key and check again */
146 		(void)printf("Key: ");
147 		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
148 			quit();
149 		(void)printf("\nAgain: ");
150 		/*
151 		 * Don't need EOF test here, if we get EOF, then s1 != s
152 		 * and the right things will happen.
153 		 */
154 		(void)fgets(s1, sizeof(s1), stdin);
155 		(void)putchar('\n');
156 		if (strcmp(s1, s)) {
157 			(void)printf("\07lock: passwords didn't match.\n");
158 			ioctl(0, TIOCSETP, &tty);
159 			exit(1);
160 		}
161 		s[0] = '\0';
162 		mypw = s1;
163 	}
164 
165 	/* set signal handlers */
166 	(void)signal(SIGINT, hi);
167 	(void)signal(SIGQUIT, hi);
168 	(void)signal(SIGTSTP, hi);
169 	(void)signal(SIGALRM, bye);
170 
171 	ntimer.it_interval = zerotime;
172 	ntimer.it_value = timeout;
173        if (!no_timeout)
174                setitimer(ITIMER_REAL, &ntimer, &otimer);
175 
176 	/* header info */
177        if (no_timeout) {
178 (void)printf("lock: %s on %s. no timeout\ntime now is %.20s%s%s",
179            ttynam, hostname, ap, tzn, ap + 19);
180        } else {
181 (void)printf("lock: %s on %s. timeout in %d minutes\ntime now is %.20s%s%s",
182 	    ttynam, hostname, sectimeout, ap, tzn, ap + 19);
183        }
184 
185 	for (;;) {
186 		(void)printf("Key: ");
187 		if (!fgets(s, sizeof(s), stdin)) {
188 			clearerr(stdin);
189 			hi();
190 			continue;
191 		}
192 		if (usemine) {
193 			s[strlen(s) - 1] = '\0';
194 			if (!strcmp(mypw, crypt(s, mypw)))
195 				break;
196 		}
197 		else if (!strcmp(s, s1))
198 			break;
199 		(void)printf("\07\n");
200 		if (ioctl(0, TIOCGETP, &ntty))
201 			exit(1);
202 	}
203 	quit();
204 	return(0); /* not reached */
205 }
206 
207 
208 static void
209 usage()
210 {
211 	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
212 	exit(1);
213 }
214 
215 void
216 hi()
217 {
218 	struct timeval timval;
219 
220        if (!gettimeofday(&timval, (struct timezone *)NULL)) {
221                (void)printf("lock: type in the unlock key. ");
222                if (no_timeout) {
223                        (void)putchar('\n');
224                } else {
225                        (void)printf("timeout in %ld:%ld minutes\n",
226                                (nexttime - timval.tv_sec) / 60,
227                                (nexttime - timval.tv_sec) % 60);
228                }
229        }
230 }
231 
232 void
233 quit()
234 {
235 	(void)putchar('\n');
236 	(void)ioctl(0, TIOCSETP, &tty);
237 	exit(0);
238 }
239 
240 void
241 bye()
242 {
243        if (!no_timeout) {
244                (void)ioctl(0, TIOCSETP, &tty);
245                (void)printf("lock: timeout\n");
246                exit(1);
247        }
248 }
249