1 /* $OpenBSD: lock.c,v 1.46 2019/07/24 20:23:09 schwarze Exp $ */
2 /* $NetBSD: lock.c,v 1.8 1996/05/07 18:32:31 jtc Exp $ */
3
4 /*
5 * Copyright (c) 1980, 1987, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Bob Toxen.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 /*
37 * Lock a terminal up until the given key or user password is entered,
38 * or the given interval times out.
39 */
40
41 #include <sys/stat.h>
42 #include <sys/time.h>
43 #include <signal.h>
44
45 #include <ctype.h>
46 #include <err.h>
47 #include <pwd.h>
48 #include <readpassphrase.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <termios.h>
53 #include <unistd.h>
54 #include <limits.h>
55
56 #include <login_cap.h>
57 #include <bsd_auth.h>
58
59 void bye(int);
60 void hi(int);
61 void usage(void);
62
63 int no_timeout = 0; /* lock terminal forever */
64
65 int
main(int argc,char * argv[])66 main(int argc, char *argv[])
67 {
68 char hostname[HOST_NAME_MAX+1], s[BUFSIZ], s1[BUFSIZ], date[256];
69 char hash[_PASSWORD_LEN];
70 char *p, *style, *nstyle, *ttynam;
71 struct itimerval ntimer, otimer;
72 struct timeval timeout;
73 int ch, sectimeout, usemine, cnt, tries = 10, backoff = 3;
74 const char *errstr;
75 struct passwd *pw;
76 struct tm *timp;
77 time_t curtime;
78 login_cap_t *lc;
79
80 sectimeout = 0;
81 style = NULL;
82 usemine = 0;
83 memset(&timeout, 0, sizeof(timeout));
84
85 if (pledge("stdio rpath wpath getpw tty proc exec", NULL) == -1)
86 err(1, "pledge");
87
88 if (!(pw = getpwuid(getuid())))
89 errx(1, "unknown uid %u.", getuid());
90
91 lc = login_getclass(pw->pw_class);
92 if (lc != NULL) {
93 /*
94 * We allow "login-tries" attempts to login but start
95 * slowing down after "login-backoff" attempts.
96 */
97 tries = login_getcapnum(lc, "login-tries", 10, 10);
98 backoff = login_getcapnum(lc, "login-backoff", 3, 3);
99 }
100
101 while ((ch = getopt(argc, argv, "a:npt:")) != -1) {
102 switch (ch) {
103 case 'a':
104 if (lc) {
105 style = login_getstyle(lc, optarg, "auth-lock");
106 if (style == NULL)
107 errx(1,
108 "invalid authentication style: %s",
109 optarg);
110 }
111 usemine = 1;
112 break;
113 case 't':
114 sectimeout = strtonum(optarg, 1, INT_MAX, &errstr);
115 if (errstr)
116 errx(1, "timeout %s: %s", errstr, optarg);
117 break;
118 case 'p':
119 usemine = 1;
120 break;
121 case 'n':
122 no_timeout = 1;
123 break;
124 default:
125 usage();
126 }
127 }
128 if (sectimeout == 0)
129 no_timeout = 1;
130
131 gethostname(hostname, sizeof(hostname));
132 if (usemine && lc == NULL)
133 errx(1, "login class not found");
134 if (!(ttynam = ttyname(STDIN_FILENO)))
135 errx(1, "not a terminal?");
136 curtime = time(NULL);
137 timp = localtime(&curtime);
138 strftime(date, sizeof(date), "%c", timp);
139
140 if (!usemine) {
141 /* get key and check again */
142 if (!readpassphrase("Key: ", s, sizeof(s), RPP_ECHO_OFF) ||
143 *s == '\0')
144 exit(0);
145 /*
146 * Don't need EOF test here, if we get EOF, then s1 != s
147 * and the right things will happen.
148 */
149 readpassphrase("Again: ", s1, sizeof(s1), RPP_ECHO_OFF);
150 if (strcmp(s1, s)) {
151 warnx("\apasswords didn't match.");
152 exit(1);
153 }
154 crypt_newhash(s, "bcrypt", hash, sizeof(hash));
155 explicit_bzero(s, sizeof(s));
156 explicit_bzero(s1, sizeof(s1));
157 }
158
159 /* set signal handlers */
160 signal(SIGINT, hi);
161 signal(SIGQUIT, hi);
162 signal(SIGTSTP, hi);
163 signal(SIGALRM, bye);
164
165 if (!no_timeout) {
166 timeout.tv_sec = (time_t)sectimeout * 60;
167 memset(&ntimer, 0, sizeof(ntimer));
168 ntimer.it_value = timeout;
169 setitimer(ITIMER_REAL, &ntimer, &otimer);
170 }
171
172 /* header info */
173 if (no_timeout) {
174 fprintf(stderr,
175 "%s: %s on %s. no timeout\ntime now is %s\n",
176 getprogname(), ttynam, hostname, date);
177 } else {
178 fprintf(stderr,
179 "%s: %s on %s. timeout in %d minutes\ntime now is %s\n",
180 getprogname(), ttynam, hostname, sectimeout, date);
181 }
182
183 for (cnt = 0;;) {
184 if (!readpassphrase("Key: ", s, sizeof(s), RPP_ECHO_OFF))
185 continue;
186 if (strlen(s) == 0) {
187 hi(0);
188 continue;
189 }
190 if (usemine) {
191 /*
192 * If user entered 's/key' or the style specified via
193 * the '-a' argument, auth_userokay() will prompt
194 * for a new password. Otherwise, use what we have.
195 */
196 if ((strcmp(s, "s/key") == 0 &&
197 (nstyle = login_getstyle(lc, "skey", "auth-lock")))
198 || ((nstyle = style) && strcmp(s, nstyle) == 0))
199 p = NULL;
200 else
201 p = s;
202 if (auth_userokay(pw->pw_name, nstyle, "auth-lock",
203 p)) {
204 explicit_bzero(s, sizeof(s));
205 break;
206 }
207 } else if (crypt_checkpass(s, hash) == 0) {
208 explicit_bzero(s, sizeof(s));
209 explicit_bzero(hash, sizeof(hash));
210 break;
211 }
212 putc('\a', stderr);
213 cnt %= tries;
214 if (++cnt > backoff) {
215 sigset_t set, oset;
216 sigfillset(&set);
217 sigprocmask(SIG_BLOCK, &set, &oset);
218 sleep((u_int)((cnt - backoff) * tries / 2));
219 sigprocmask(SIG_SETMASK, &oset, NULL);
220 }
221 }
222
223 exit(0);
224 }
225
226 void
hi(int signo)227 hi(int signo)
228 {
229 struct itimerval left;
230
231 dprintf(STDERR_FILENO, "%s: type in the unlock key.",
232 getprogname());
233 if (!no_timeout) {
234 getitimer(ITIMER_REAL, &left);
235 dprintf(STDERR_FILENO, " timeout in %lld:%02d minutes",
236 (long long)(left.it_value.tv_sec / 60),
237 (int)(left.it_value.tv_sec % 60));
238 }
239 dprintf(STDERR_FILENO, "\n");
240 }
241
242 void
bye(int signo)243 bye(int signo)
244 {
245
246 if (!no_timeout)
247 warnx("timeout");
248 _exit(1);
249 }
250
251 void
usage(void)252 usage(void)
253 {
254 fprintf(stderr, "usage: %s [-np] [-a style] [-t timeout]\n",
255 getprogname());
256 exit(1);
257 }
258