lock.c revision 1590 
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 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
44static 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
67void quit(), bye(), hi();
68
69struct timeval	timeout;
70struct timeval	zerotime;
71struct sgttyb	tty, ntty;
72long	nexttime;			/* keep the timeout time */
73
74/*ARGSUSED*/
75main(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
199void
200hi()
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
209void
210quit()
211{
212	(void)putchar('\n');
213	(void)ioctl(0, TIOCSETP, &tty);
214	exit(0);
215}
216
217void
218bye()
219{
220	(void)ioctl(0, TIOCSETP, &tty);
221	(void)printf("lock: timeout\n");
222	exit(1);
223}
224