lock.c revision 50477 
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
38static 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
45static char sccsid[] = "@(#)lock.c	8.1 (Berkeley) 6/6/93";
46#endif
47static const char rcsid[] =
48  "$FreeBSD: head/usr.bin/lock/lock.c 50477 1999-08-28 01:08:13Z peter $";
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
74void quit(), bye(), hi();
75static void usage __P((void));
76
77struct timeval	timeout;
78struct timeval	zerotime;
79struct sgttyb	tty, ntty;
80long	nexttime;			/* keep the timeout time */
81int            no_timeout;                     /* lock terminal forever */
82
83/*ARGSUSED*/
84int
85main(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
208static void
209usage()
210{
211	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
212	exit(1);
213}
214
215void
216hi()
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
232void
233quit()
234{
235	(void)putchar('\n');
236	(void)ioctl(0, TIOCSETP, &tty);
237	exit(0);
238}
239
240void
241bye()
242{
243       if (!no_timeout) {
244               (void)ioctl(0, TIOCSETP, &tty);
245               (void)printf("lock: timeout\n");
246               exit(1);
247       }
248}
249