xref: /freebsd/usr.bin/lock/lock.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
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 #endif /* not lint */
48 #include <sys/cdefs.h>
49 __FBSDID("$FreeBSD$");
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 <sys/consio.h>
64 #include <err.h>
65 #include <ctype.h>
66 #include <pwd.h>
67 #include <sgtty.h>
68 #include <stdio.h>
69 #include <stdlib.h>
70 #include <string.h>
71 #include <syslog.h>
72 #include <unistd.h>
73 #include <varargs.h>
74 
75 #define	TIMEOUT	15
76 
77 void quit(int);
78 void bye(int);
79 void hi(int);
80 static void usage(void);
81 
82 struct timeval	timeout;
83 struct timeval	zerotime;
84 struct sgttyb	tty, ntty;
85 long	nexttime;			/* keep the timeout time */
86 int            no_timeout;                     /* lock terminal forever */
87 int	vtyunlock;			/* Unlock flag and code. */
88 
89 /*ARGSUSED*/
90 int
91 main(argc, argv)
92 	int argc;
93 	char **argv;
94 {
95 	struct passwd *pw;
96 	struct timeval timval;
97 	time_t timval_sec;
98 	struct itimerval ntimer, otimer;
99 	struct tm *timp;
100 	int ch, failures, sectimeout, usemine, vtylock;
101 	char *ap, *mypw, *ttynam, *tzn;
102 	char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
103 
104 	openlog("lock", LOG_ODELAY, LOG_AUTH);
105 
106 	sectimeout = TIMEOUT;
107 	mypw = NULL;
108 	usemine = 0;
109 	no_timeout = 0;
110 	vtylock = 0;
111 	while ((ch = getopt(argc, argv, "npt:v")) != -1)
112 		switch((char)ch) {
113 		case 't':
114 			if ((sectimeout = atoi(optarg)) <= 0)
115 				errx(1, "illegal timeout value");
116 			break;
117 		case 'p':
118 			usemine = 1;
119 			if (!(pw = getpwuid(getuid())))
120 				errx(1, "unknown uid %d", getuid());
121 			mypw = strdup(pw->pw_passwd);
122 			break;
123 		case 'n':
124 			no_timeout = 1;
125 			break;
126 		case 'v':
127 			vtylock = 1;
128 			break;
129 		case '?':
130 		default:
131 			usage();
132 		}
133 	timeout.tv_sec = sectimeout * 60;
134 
135 	setuid(getuid());		/* discard privs */
136 
137 	if (ioctl(0, TIOCGETP, &tty))	/* get information for header */
138 		exit(1);
139 	gethostname(hostname, sizeof(hostname));
140 	if (!(ttynam = ttyname(0)))
141 		errx(1, "not a terminal?");
142 	if (gettimeofday(&timval, (struct timezone *)NULL))
143 		err(1, "gettimeofday");
144 	nexttime = timval.tv_sec + (sectimeout * 60);
145 	timval_sec = timval.tv_sec;
146 	timp = localtime(&timval_sec);
147 	ap = asctime(timp);
148 	tzn = timp->tm_zone;
149 
150 	(void)signal(SIGINT, quit);
151 	(void)signal(SIGQUIT, quit);
152 	ntty = tty; ntty.sg_flags &= ~ECHO;
153 	(void)ioctl(0, TIOCSETP, &ntty);
154 
155 	if (!mypw) {
156 		/* get key and check again */
157 		(void)printf("Key: ");
158 		if (!fgets(s, sizeof(s), stdin) || *s == '\n')
159 			quit(0);
160 		(void)printf("\nAgain: ");
161 		/*
162 		 * Don't need EOF test here, if we get EOF, then s1 != s
163 		 * and the right things will happen.
164 		 */
165 		(void)fgets(s1, sizeof(s1), stdin);
166 		(void)putchar('\n');
167 		if (strcmp(s1, s)) {
168 			(void)printf("\07lock: passwords didn't match.\n");
169 			ioctl(0, TIOCSETP, &tty);
170 			exit(1);
171 		}
172 		s[0] = '\0';
173 		mypw = s1;
174 	}
175 
176 	/* set signal handlers */
177 	(void)signal(SIGINT, hi);
178 	(void)signal(SIGQUIT, hi);
179 	(void)signal(SIGTSTP, hi);
180 	(void)signal(SIGALRM, bye);
181 
182 	ntimer.it_interval = zerotime;
183 	ntimer.it_value = timeout;
184 	if (!no_timeout)
185 		setitimer(ITIMER_REAL, &ntimer, &otimer);
186 	if (vtylock) {
187 		/*
188 		 * If this failed, we want to err out; warn isn't good
189 		 * enough, since we don't want the user to think that
190 		 * everything is nice and locked because they got a
191 		 * "Key:" prompt.
192 		 */
193 		if (ioctl(0, VT_LOCKSWITCH, &vtylock) == -1) {
194 			(void)ioctl(0, TIOCSETP, &tty);
195 			err(1, "locking vty");
196 		}
197 		vtyunlock = 0x2;
198 	}
199 
200 	/* header info */
201 	(void)printf("lock: %s on %s.", ttynam, hostname);
202 	if (no_timeout)
203 		(void)printf(" no timeout.");
204 	else
205 		(void)printf(" timeout in %d minute%s.", sectimeout,
206 		    sectimeout != 1 ? "s" : "");
207 	if (vtylock)
208 		(void)printf(" vty locked.");
209 	(void)printf("\ntime now is %.20s%s%s", ap, tzn, ap + 19);
210 
211 	failures = 0;
212 
213 	for (;;) {
214 		(void)printf("Key: ");
215 		if (!fgets(s, sizeof(s), stdin)) {
216 			clearerr(stdin);
217 			hi(0);
218 			continue;
219 		}
220 		if (usemine) {
221 			s[strlen(s) - 1] = '\0';
222 			if (!strcmp(mypw, crypt(s, mypw)))
223 				break;
224 		}
225 		else if (!strcmp(s, s1))
226 			break;
227 		(void)printf("\07\n");
228 	    	failures++;
229 		if (getuid() == 0)
230 	    	    syslog(LOG_NOTICE, "%d ROOT UNLOCK FAILURE%s (%s on %s)",
231 			failures, failures > 1 ? "S": "", ttynam, hostname);
232 		if (ioctl(0, TIOCGETP, &ntty))
233 			exit(1);
234 		sleep(1);		/* to discourage guessing */
235 	}
236 	if (getuid() == 0)
237 		syslog(LOG_NOTICE, "ROOT UNLOCK ON hostname %s port %s",
238 		    hostname, ttynam);
239 	quit(0);
240 	return(0); /* not reached */
241 }
242 
243 
244 static void
245 usage()
246 {
247 	(void)fprintf(stderr, "usage: lock [-npv] [-t timeout]\n");
248 	exit(1);
249 }
250 
251 void
252 hi(int signo __unused)
253 {
254 	struct timeval timval;
255 
256 	if (!gettimeofday(&timval, (struct timezone *)NULL)) {
257 		(void)printf("lock: type in the unlock key. ");
258 		if (no_timeout) {
259 			(void)putchar('\n');
260 		} else {
261 			(void)printf("timeout in %ld:%ld minutes\n",
262 			    (nexttime - timval.tv_sec) / 60,
263 			    (nexttime - timval.tv_sec) % 60);
264 		}
265 	}
266 }
267 
268 void
269 quit(int signo __unused)
270 {
271 	(void)putchar('\n');
272 	(void)ioctl(0, TIOCSETP, &tty);
273 	if (vtyunlock)
274 		(void)ioctl(0, VT_LOCKSWITCH, &vtyunlock);
275 	exit(0);
276 }
277 
278 void
279 bye(int signo __unused)
280 {
281 	if (!no_timeout) {
282 		(void)ioctl(0, TIOCSETP, &tty);
283 		if (vtyunlock)
284 			(void)ioctl(0, VT_LOCKSWITCH, &vtyunlock);
285 		(void)printf("lock: timeout\n");
286 		exit(1);
287 	}
288 }
289