xref: /freebsd/usr.bin/lock/lock.c (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
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(int);
77 void bye(int);
78 void hi(int);
79 static void usage(void);
80 
81 struct timeval	timeout;
82 struct timeval	zerotime;
83 struct sgttyb	tty, ntty;
84 long	nexttime;			/* keep the timeout time */
85 int            no_timeout;                     /* lock terminal forever */
86 
87 /*ARGSUSED*/
88 int
89 main(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 
222 static void
223 usage()
224 {
225 	(void)fprintf(stderr, "usage: lock [-n] [-p] [-t timeout]\n");
226 	exit(1);
227 }
228 
229 void
230 hi(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 
246 void
247 quit(int signo __unused)
248 {
249 	(void)putchar('\n');
250 	(void)ioctl(0, TIOCSETP, &tty);
251 	exit(0);
252 }
253 
254 void
255 bye(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