xref: /freebsd/usr.bin/lock/lock.c (revision daf1cffce2e07931f27c6c6998652e90df6ba87e)
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
38 static 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
45 static char sccsid[] = "@(#)lock.c	8.1 (Berkeley) 6/6/93";
46 #endif
47 static const char rcsid[] =
48   "$FreeBSD$";
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 <syslog.h>
71 #include <unistd.h>
72 #include <varargs.h>
73 
74 #define	TIMEOUT	15
75 
76 void quit(), bye(), hi();
77 static void usage __P((void));
78 
79 struct timeval	timeout;
80 struct timeval	zerotime;
81 struct sgttyb	tty, ntty;
82 long	nexttime;			/* keep the timeout time */
83 int            no_timeout;                     /* lock terminal forever */
84 
85 /*ARGSUSED*/
86 int
87 main(argc, argv)
88 	int argc;
89 	char **argv;
90 {
91 	struct passwd *pw;
92 	struct timeval timval;
93 	time_t timval_sec;
94 	struct itimerval ntimer, otimer;
95 	struct tm *timp;
96 	int ch, failures, sectimeout, usemine;
97 	char *ap, *mypw, *ttynam, *tzn;
98 	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
99 	char *crypt(), *ttyname();
100 
101 	openlog("lock", LOG_ODELAY, LOG_AUTH);
102 
103 	sectimeout = TIMEOUT;
104 	mypw = NULL;
105 	usemine = 0;
106        no_timeout = 0;
107        while ((ch = getopt(argc, argv, "npt:")) != -1)
108 		switch((char)ch) {
109 		case 't':
110 			if ((sectimeout = atoi(optarg)) <= 0)
111 				errx(1, "illegal timeout value");
112 			break;
113 		case 'p':
114 			usemine = 1;
115 			if (!(pw = getpwuid(getuid())))
116 				errx(1, "unknown uid %d", getuid());
117 			mypw = strdup(pw->pw_passwd);
118 			break;
119                case 'n':
120                        no_timeout = 1;
121                        break;
122 		case '?':
123 		default:
124 			usage();
125 	}
126 	timeout.tv_sec = sectimeout * 60;
127 
128 	setuid(getuid());		/* discard privs */
129 
130 	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
131 		exit(1);
132 	gethostname(hostname, sizeof(hostname));
133 	if (!(ttynam = ttyname(0)))
134 		errx(1, "not a terminal?");
135 	if (gettimeofday(&timval, (struct timezone *)NULL))
136 		err(1, "gettimeofday");
137 	nexttime = timval.tv_sec + (sectimeout * 60);
138 	timval_sec = timval.tv_sec;
139 	timp = localtime(&timval_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] = '\0';
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        failures = 0;
189 
190 	for (;;) {
191 		(void)printf("Key: ");
192 		if (!fgets(s, sizeof(s), stdin)) {
193 			clearerr(stdin);
194 			hi();
195 			continue;
196 		}
197 		if (usemine) {
198 			s[strlen(s) - 1] = '\0';
199 			if (!strcmp(mypw, crypt(s, mypw)))
200 				break;
201 		}
202 		else if (!strcmp(s, s1))
203 			break;
204 		(void)printf("\07\n");
205 	    	failures++;
206 		if (getuid() == 0)
207 	    	    syslog(LOG_NOTICE, "%d ROOT UNLOCK FAILURE%s (%s on %s)",
208 			failures, failures > 1 ? "S": "", ttynam, hostname);
209 		if (ioctl(0, TIOCGETP, &ntty))
210 			exit(1);
211 		sleep(1);		/* to discourage guessing */
212 	}
213 	if (getuid() == 0)
214 	    syslog(LOG_NOTICE, "ROOT UNLOCK ON hostname %s port %s",
215 		   hostname, ttynam);
216 	quit();
217 	return(0); /* not reached */
218 }
219 
220 
221 static void
222 usage()
223 {
224 	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
225 	exit(1);
226 }
227 
228 void
229 hi()
230 {
231 	struct timeval timval;
232 
233        if (!gettimeofday(&timval, (struct timezone *)NULL)) {
234                (void)printf("lock: type in the unlock key. ");
235                if (no_timeout) {
236                        (void)putchar('\n');
237                } else {
238                        (void)printf("timeout in %ld:%ld minutes\n",
239                                (nexttime - timval.tv_sec) / 60,
240                                (nexttime - timval.tv_sec) % 60);
241                }
242        }
243 }
244 
245 void
246 quit()
247 {
248 	(void)putchar('\n');
249 	(void)ioctl(0, TIOCSETP, &tty);
250 	exit(0);
251 }
252 
253 void
254 bye()
255 {
256        if (!no_timeout) {
257                (void)ioctl(0, TIOCSETP, &tty);
258                (void)printf("lock: timeout\n");
259                exit(1);
260        }
261 }
262