lock.c revision 18295 
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 */
73int            no_timeout;                     /* lock terminal forever */
74
75/*ARGSUSED*/
76main(argc, argv)
77	int argc;
78	char **argv;
79{
80	extern char *optarg;
81	extern int errno, optind;
82	struct passwd *pw;
83	struct timeval timval;
84	struct itimerval ntimer, otimer;
85	struct tm *timp;
86	int ch, sectimeout, usemine;
87	char *ap, *mypw, *ttynam, *tzn;
88	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
89	char *crypt(), *ttyname();
90
91	sectimeout = TIMEOUT;
92	mypw = NULL;
93	usemine = 0;
94       no_timeout = 0;
95       while ((ch = getopt(argc, argv, "npt:")) != EOF)
96		switch((char)ch) {
97		case 't':
98			if ((sectimeout = atoi(optarg)) <= 0) {
99				(void)fprintf(stderr,
100				    "lock: illegal timeout value.\n");
101				exit(1);
102			}
103			break;
104		case 'p':
105			usemine = 1;
106			if (!(pw = getpwuid(getuid()))) {
107				(void)fprintf(stderr,
108				    "lock: unknown uid %d.\n", getuid());
109				exit(1);
110			}
111			mypw = strdup(pw->pw_passwd);
112			break;
113               case 'n':
114                       no_timeout = 1;
115                       break;
116		case '?':
117		default:
118			(void)fprintf(stderr,
119                           "usage: lock [-n] [-p] [-t timeout]\n");
120			exit(1);
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		(void)printf("lock: not a terminal?\n");
131		exit(1);
132	}
133	if (gettimeofday(&timval, (struct timezone *)NULL)) {
134		(void)fprintf(stderr,
135		    "lock: gettimeofday: %s\n", strerror(errno));
136		exit(1);
137	}
138	nexttime = timval.tv_sec + (sectimeout * 60);
139	timp = localtime(&timval.tv_sec);
140	ap = asctime(timp);
141	tzn = timp->tm_zone;
142
143	(void)signal(SIGINT, quit);
144	(void)signal(SIGQUIT, quit);
145	ntty = tty; ntty.sg_flags &= ~ECHO;
146	(void)ioctl(0, TIOCSETP, &ntty);
147
148	if (!mypw) {
149		/* get key and check again */
150		(void)printf("Key: ");
151		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
152			quit();
153		(void)printf("\nAgain: ");
154		/*
155		 * Don't need EOF test here, if we get EOF, then s1 != s
156		 * and the right things will happen.
157		 */
158		(void)fgets(s1, sizeof(s1), stdin);
159		(void)putchar('\n');
160		if (strcmp(s1, s)) {
161			(void)printf("\07lock: passwords didn't match.\n");
162			ioctl(0, TIOCSETP, &tty);
163			exit(1);
164		}
165		s[0] = NULL;
166		mypw = s1;
167	}
168
169	/* set signal handlers */
170	(void)signal(SIGINT, hi);
171	(void)signal(SIGQUIT, hi);
172	(void)signal(SIGTSTP, hi);
173	(void)signal(SIGALRM, bye);
174
175	ntimer.it_interval = zerotime;
176	ntimer.it_value = timeout;
177       if (!no_timeout)
178               setitimer(ITIMER_REAL, &ntimer, &otimer);
179
180	/* header info */
181       if (no_timeout) {
182(void)printf("lock: %s on %s. no timeout\ntime now is %.20s%s%s",
183           ttynam, hostname, ap, tzn, ap + 19);
184       } else {
185(void)printf("lock: %s on %s. timeout in %d minutes\ntime now is %.20s%s%s",
186	    ttynam, hostname, sectimeout, ap, tzn, ap + 19);
187       }
188
189	for (;;) {
190		(void)printf("Key: ");
191		if (!fgets(s, sizeof(s), stdin)) {
192			clearerr(stdin);
193			hi();
194			continue;
195		}
196		if (usemine) {
197			s[strlen(s) - 1] = '\0';
198			if (!strcmp(mypw, crypt(s, mypw)))
199				break;
200		}
201		else if (!strcmp(s, s1))
202			break;
203		(void)printf("\07\n");
204		if (ioctl(0, TIOCGETP, &ntty))
205			exit(1);
206	}
207	quit();
208}
209
210void
211hi()
212{
213	struct timeval timval;
214
215       if (!gettimeofday(&timval, (struct timezone *)NULL)) {
216               (void)printf("lock: type in the unlock key. ");
217               if (no_timeout) {
218                       (void)putchar('\n');
219               } else {
220                       (void)printf("timeout in %ld:%ld minutes\n",
221                               (nexttime - timval.tv_sec) / 60,
222                               (nexttime - timval.tv_sec) % 60);
223               }
224       }
225}
226
227void
228quit()
229{
230	(void)putchar('\n');
231	(void)ioctl(0, TIOCSETP, &tty);
232	exit(0);
233}
234
235void
236bye()
237{
238       if (!no_timeout) {
239               (void)ioctl(0, TIOCSETP, &tty);
240               (void)printf("lock: timeout\n");
241               exit(1);
242       }
243}
244