lock.c revision 27575 
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	"$Id$";
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	struct itimerval ntimer, otimer;
92	struct tm *timp;
93	int ch, sectimeout, usemine;
94	char *ap, *mypw, *ttynam, *tzn;
95	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
96	char *crypt(), *ttyname();
97
98	sectimeout = TIMEOUT;
99	mypw = NULL;
100	usemine = 0;
101       no_timeout = 0;
102       while ((ch = getopt(argc, argv, "npt:")) != -1)
103		switch((char)ch) {
104		case 't':
105			if ((sectimeout = atoi(optarg)) <= 0)
106				errx(1, "illegal timeout value");
107			break;
108		case 'p':
109			usemine = 1;
110			if (!(pw = getpwuid(getuid())))
111				errx(1, "unknown uid %d", getuid());
112			mypw = strdup(pw->pw_passwd);
113			break;
114               case 'n':
115                       no_timeout = 1;
116                       break;
117		case '?':
118		default:
119			usage();
120	}
121	timeout.tv_sec = sectimeout * 60;
122
123	setuid(getuid());		/* discard privs */
124
125	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
126		exit(1);
127	gethostname(hostname, sizeof(hostname));
128	if (!(ttynam = ttyname(0)))
129		errx(1, "not a terminal?");
130	if (gettimeofday(&timval, (struct timezone *)NULL))
131		err(1, "gettimeofday");
132	nexttime = timval.tv_sec + (sectimeout * 60);
133	timp = localtime(&timval.tv_sec);
134	ap = asctime(timp);
135	tzn = timp->tm_zone;
136
137	(void)signal(SIGINT, quit);
138	(void)signal(SIGQUIT, quit);
139	ntty = tty; ntty.sg_flags &= ~ECHO;
140	(void)ioctl(0, TIOCSETP, &ntty);
141
142	if (!mypw) {
143		/* get key and check again */
144		(void)printf("Key: ");
145		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
146			quit();
147		(void)printf("\nAgain: ");
148		/*
149		 * Don't need EOF test here, if we get EOF, then s1 != s
150		 * and the right things will happen.
151		 */
152		(void)fgets(s1, sizeof(s1), stdin);
153		(void)putchar('\n');
154		if (strcmp(s1, s)) {
155			(void)printf("\07lock: passwords didn't match.\n");
156			ioctl(0, TIOCSETP, &tty);
157			exit(1);
158		}
159		s[0] = '\0';
160		mypw = s1;
161	}
162
163	/* set signal handlers */
164	(void)signal(SIGINT, hi);
165	(void)signal(SIGQUIT, hi);
166	(void)signal(SIGTSTP, hi);
167	(void)signal(SIGALRM, bye);
168
169	ntimer.it_interval = zerotime;
170	ntimer.it_value = timeout;
171       if (!no_timeout)
172               setitimer(ITIMER_REAL, &ntimer, &otimer);
173
174	/* header info */
175       if (no_timeout) {
176(void)printf("lock: %s on %s. no timeout\ntime now is %.20s%s%s",
177           ttynam, hostname, ap, tzn, ap + 19);
178       } else {
179(void)printf("lock: %s on %s. timeout in %d minutes\ntime now is %.20s%s%s",
180	    ttynam, hostname, sectimeout, ap, tzn, ap + 19);
181       }
182
183	for (;;) {
184		(void)printf("Key: ");
185		if (!fgets(s, sizeof(s), stdin)) {
186			clearerr(stdin);
187			hi();
188			continue;
189		}
190		if (usemine) {
191			s[strlen(s) - 1] = '\0';
192			if (!strcmp(mypw, crypt(s, mypw)))
193				break;
194		}
195		else if (!strcmp(s, s1))
196			break;
197		(void)printf("\07\n");
198		if (ioctl(0, TIOCGETP, &ntty))
199			exit(1);
200	}
201	quit();
202	return(0); /* not reached */
203}
204
205
206static void
207usage()
208{
209	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
210	exit(1);
211}
212
213void
214hi()
215{
216	struct timeval timval;
217
218       if (!gettimeofday(&timval, (struct timezone *)NULL)) {
219               (void)printf("lock: type in the unlock key. ");
220               if (no_timeout) {
221                       (void)putchar('\n');
222               } else {
223                       (void)printf("timeout in %ld:%ld minutes\n",
224                               (nexttime - timval.tv_sec) / 60,
225                               (nexttime - timval.tv_sec) % 60);
226               }
227       }
228}
229
230void
231quit()
232{
233	(void)putchar('\n');
234	(void)ioctl(0, TIOCSETP, &tty);
235	exit(0);
236}
237
238void
239bye()
240{
241       if (!no_timeout) {
242               (void)ioctl(0, TIOCSETP, &tty);
243               (void)printf("lock: timeout\n");
244               exit(1);
245       }
246}
247