lock.c revision 99709 
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
47#endif /* not lint */
48#include <sys/cdefs.h>
49__FBSDID("$FreeBSD: head/usr.bin/lock/lock.c 99709 2002-07-10 04:05:33Z dd $");
50
51/*
52 * Lock a terminal up until the given key is entered or the given
53 * 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 <syslog.h>
71#include <unistd.h>
72#include <varargs.h>
73
74#define	TIMEOUT	15
75
76void quit(int);
77void bye(int);
78void hi(int);
79static void usage(void);
80
81struct timeval	timeout;
82struct timeval	zerotime;
83struct sgttyb	tty, ntty;
84long	nexttime;			/* keep the timeout time */
85int            no_timeout;                     /* lock terminal forever */
86
87/*ARGSUSED*/
88int
89main(argc, argv)
90	int argc;
91	char **argv;
92{
93	struct passwd *pw;
94	struct timeval timval;
95	time_t timval_sec;
96	struct itimerval ntimer, otimer;
97	struct tm *timp;
98	int ch, failures, sectimeout, usemine;
99	char *ap, *mypw, *ttynam, *tzn;
100	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
101
102	openlog("lock", LOG_ODELAY, LOG_AUTH);
103
104	sectimeout = TIMEOUT;
105	mypw = NULL;
106	usemine = 0;
107	no_timeout = 0;
108	while ((ch = getopt(argc, argv, "npt:")) != -1)
109		switch((char)ch) {
110		case 't':
111			if ((sectimeout = atoi(optarg)) <= 0)
112				errx(1, "illegal timeout value");
113			break;
114		case 'p':
115			usemine = 1;
116			if (!(pw = getpwuid(getuid())))
117				errx(1, "unknown uid %d", getuid());
118			mypw = strdup(pw->pw_passwd);
119			break;
120		case 'n':
121			no_timeout = 1;
122			break;
123		case '?':
124		default:
125			usage();
126		}
127	timeout.tv_sec = sectimeout * 60;
128
129	setuid(getuid());		/* discard privs */
130
131	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
132		exit(1);
133	gethostname(hostname, sizeof(hostname));
134	if (!(ttynam = ttyname(0)))
135		errx(1, "not a terminal?");
136	if (gettimeofday(&timval, (struct timezone *)NULL))
137		err(1, "gettimeofday");
138	nexttime = timval.tv_sec + (sectimeout * 60);
139	timval_sec = timval.tv_sec;
140	timp = localtime(&timval_sec);
141	ap = asctime(timp);
142	tzn = timp->tm_zone;
143
144	(void)signal(SIGINT, quit);
145	(void)signal(SIGQUIT, quit);
146	ntty = tty; ntty.sg_flags &= ~ECHO;
147	(void)ioctl(0, TIOCSETP, &ntty);
148
149	if (!mypw) {
150		/* get key and check again */
151		(void)printf("Key: ");
152		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
153			quit(0);
154		(void)printf("\nAgain: ");
155		/*
156		 * Don't need EOF test here, if we get EOF, then s1 != s
157		 * and the right things will happen.
158		 */
159		(void)fgets(s1, sizeof(s1), stdin);
160		(void)putchar('\n');
161		if (strcmp(s1, s)) {
162			(void)printf("\07lock: passwords didn't match.\n");
163			ioctl(0, TIOCSETP, &tty);
164			exit(1);
165		}
166		s[0] = '\0';
167		mypw = s1;
168	}
169
170	/* set signal handlers */
171	(void)signal(SIGINT, hi);
172	(void)signal(SIGQUIT, hi);
173	(void)signal(SIGTSTP, hi);
174	(void)signal(SIGALRM, bye);
175
176	ntimer.it_interval = zerotime;
177	ntimer.it_value = timeout;
178	if (!no_timeout)
179		setitimer(ITIMER_REAL, &ntimer, &otimer);
180
181	/* header info */
182	if (no_timeout) {
183(void)printf("lock: %s on %s. no timeout\ntime now is %.20s%s%s",
184	    ttynam, hostname, ap, tzn, ap + 19);
185	} else {
186(void)printf("lock: %s on %s. timeout in %d minutes\ntime now is %.20s%s%s",
187	    ttynam, hostname, sectimeout, ap, tzn, ap + 19);
188	}
189	failures = 0;
190
191	for (;;) {
192		(void)printf("Key: ");
193		if (!fgets(s, sizeof(s), stdin)) {
194			clearerr(stdin);
195			hi(0);
196			continue;
197		}
198		if (usemine) {
199			s[strlen(s) - 1] = '\0';
200			if (!strcmp(mypw, crypt(s, mypw)))
201				break;
202		}
203		else if (!strcmp(s, s1))
204			break;
205		(void)printf("\07\n");
206	    	failures++;
207		if (getuid() == 0)
208	    	    syslog(LOG_NOTICE, "%d ROOT UNLOCK FAILURE%s (%s on %s)",
209			failures, failures > 1 ? "S": "", ttynam, hostname);
210		if (ioctl(0, TIOCGETP, &ntty))
211			exit(1);
212		sleep(1);		/* to discourage guessing */
213	}
214	if (getuid() == 0)
215		syslog(LOG_NOTICE, "ROOT UNLOCK ON hostname %s port %s",
216		    hostname, ttynam);
217	quit(0);
218	return(0); /* not reached */
219}
220
221
222static void
223usage()
224{
225	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
226	exit(1);
227}
228
229void
230hi(int signo __unused)
231{
232	struct timeval timval;
233
234	if (!gettimeofday(&timval, (struct timezone *)NULL)) {
235		(void)printf("lock: type in the unlock key. ");
236		if (no_timeout) {
237			(void)putchar('\n');
238		} else {
239			(void)printf("timeout in %ld:%ld minutes\n",
240			    (nexttime - timval.tv_sec) / 60,
241			    (nexttime - timval.tv_sec) % 60);
242		}
243	}
244}
245
246void
247quit(int signo __unused)
248{
249	(void)putchar('\n');
250	(void)ioctl(0, TIOCSETP, &tty);
251	exit(0);
252}
253
254void
255bye(int signo __unused)
256{
257	if (!no_timeout) {
258		(void)ioctl(0, TIOCSETP, &tty);
259		(void)printf("lock: timeout\n");
260		exit(1);
261	}
262}
263