1 /* $OpenBSD: lock.c,v 1.41 2017/09/06 21:02:31 tb 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 is entered, until the root 38 * password is entered, or the given interval times out. 39 * 40 * Timeout interval is by default TIMEOUT, it can be changed with 41 * an argument of the form -time where time is in minutes 42 */ 43 44 #include <sys/stat.h> 45 #include <sys/time.h> 46 #include <signal.h> 47 48 #include <ctype.h> 49 #include <err.h> 50 #include <pwd.h> 51 #include <readpassphrase.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <termios.h> 56 #include <unistd.h> 57 #include <limits.h> 58 59 #include <login_cap.h> 60 #include <bsd_auth.h> 61 62 #define TIMEOUT 15 63 64 void bye(int); 65 void hi(int); 66 67 int no_timeout; /* lock terminal forever */ 68 69 int 70 main(int argc, char *argv[]) 71 { 72 char hostname[HOST_NAME_MAX+1], s[BUFSIZ], s1[BUFSIZ], date[256]; 73 char hash[_PASSWORD_LEN]; 74 char *p, *style, *nstyle, *ttynam; 75 struct itimerval ntimer, otimer; 76 struct timeval timeout; 77 int ch, sectimeout, usemine, cnt, tries = 10, backoff = 3; 78 const char *errstr; 79 struct passwd *pw; 80 struct tm *timp; 81 time_t curtime; 82 login_cap_t *lc; 83 84 sectimeout = TIMEOUT; 85 style = NULL; 86 usemine = 0; 87 no_timeout = 0; 88 memset(&timeout, 0, sizeof(timeout)); 89 90 if (pledge("stdio rpath wpath getpw tty proc exec", NULL) == -1) 91 err(1, "pledge"); 92 93 if (!(pw = getpwuid(getuid()))) 94 errx(1, "unknown uid %u.", getuid()); 95 96 lc = login_getclass(pw->pw_class); 97 if (lc != NULL) { 98 /* 99 * We allow "login-tries" attempts to login but start 100 * slowing down after "login-backoff" attempts. 101 */ 102 tries = login_getcapnum(lc, "login-tries", 10, 10); 103 backoff = login_getcapnum(lc, "login-backoff", 3, 3); 104 } 105 106 while ((ch = getopt(argc, argv, "a:npt:")) != -1) { 107 switch (ch) { 108 case 'a': 109 if (lc) { 110 style = login_getstyle(lc, optarg, "auth-lock"); 111 if (style == NULL) 112 errx(1, 113 "invalid authentication style: %s", 114 optarg); 115 } 116 usemine = 1; 117 break; 118 case 't': 119 sectimeout = strtonum(optarg, 1, INT_MAX, &errstr); 120 if (errstr) 121 errx(1, "timeout %s: %s", errstr, optarg); 122 break; 123 case 'p': 124 usemine = 1; 125 break; 126 case 'n': 127 no_timeout = 1; 128 break; 129 default: 130 fprintf(stderr, 131 "usage: %s [-np] [-a style] [-t timeout]\n", 132 getprogname()); 133 exit(1); 134 } 135 } 136 timeout.tv_sec = sectimeout * 60; 137 138 gethostname(hostname, sizeof(hostname)); 139 if (usemine && lc == NULL) 140 errx(1, "login class not found"); 141 if (!(ttynam = ttyname(STDIN_FILENO))) 142 errx(1, "not a terminal?"); 143 curtime = time(NULL); 144 timp = localtime(&curtime); 145 strftime(date, sizeof(date), "%c", timp); 146 147 if (!usemine) { 148 /* get key and check again */ 149 if (!readpassphrase("Key: ", s, sizeof(s), RPP_ECHO_OFF) || 150 *s == '\0') 151 exit(0); 152 /* 153 * Don't need EOF test here, if we get EOF, then s1 != s 154 * and the right things will happen. 155 */ 156 readpassphrase("Again: ", s1, sizeof(s1), RPP_ECHO_OFF); 157 if (strcmp(s1, s)) { 158 warnx("\apasswords didn't match."); 159 exit(1); 160 } 161 crypt_newhash(s, "bcrypt", hash, sizeof(hash)); 162 explicit_bzero(s, sizeof(s)); 163 explicit_bzero(s1, sizeof(s1)); 164 } 165 166 /* set signal handlers */ 167 signal(SIGINT, hi); 168 signal(SIGQUIT, hi); 169 signal(SIGTSTP, hi); 170 signal(SIGALRM, bye); 171 172 memset(&ntimer, 0, sizeof(ntimer)); 173 ntimer.it_value = timeout; 174 if (!no_timeout) 175 setitimer(ITIMER_REAL, &ntimer, &otimer); 176 177 /* header info */ 178 if (no_timeout) { 179 fprintf(stderr, 180 "%s: %s on %s. no timeout\ntime now is %s\n", 181 getprogname(), ttynam, hostname, date); 182 } else { 183 fprintf(stderr, 184 "%s: %s on %s. timeout in %d minutes\ntime now is %s\n", 185 getprogname(), ttynam, hostname, sectimeout, date); 186 } 187 188 for (cnt = 0;;) { 189 if (!readpassphrase("Key: ", s, sizeof(s), RPP_ECHO_OFF)) 190 continue; 191 if (strlen(s) == 0) { 192 hi(0); 193 continue; 194 } 195 if (usemine) { 196 /* 197 * If user entered 's/key' or the style specified via 198 * the '-a' argument, auth_userokay() will prompt 199 * for a new password. Otherwise, use what we have. 200 */ 201 if ((strcmp(s, "s/key") == 0 && 202 (nstyle = login_getstyle(lc, "skey", "auth-lock"))) 203 || ((nstyle = style) && strcmp(s, nstyle) == 0)) 204 p = NULL; 205 else 206 p = s; 207 if (auth_userokay(pw->pw_name, nstyle, "auth-lock", 208 p)) { 209 explicit_bzero(s, sizeof(s)); 210 break; 211 } 212 } else if (crypt_checkpass(s, hash) == 0) { 213 explicit_bzero(s, sizeof(s)); 214 explicit_bzero(hash, sizeof(hash)); 215 break; 216 } 217 putc('\a', stderr); 218 cnt %= tries; 219 if (++cnt > backoff) { 220 sigset_t set, oset; 221 sigfillset(&set); 222 sigprocmask(SIG_BLOCK, &set, &oset); 223 sleep((u_int)((cnt - backoff) * tries / 2)); 224 sigprocmask(SIG_SETMASK, &oset, NULL); 225 } 226 } 227 228 exit(0); 229 } 230 231 void 232 hi(int signo) 233 { 234 struct itimerval left; 235 236 dprintf(STDERR_FILENO, "%s: type in the unlock key.", 237 getprogname()); 238 if (!no_timeout) { 239 getitimer(ITIMER_REAL, &left); 240 dprintf(STDERR_FILENO, " timeout in %lld:%02d minutes", 241 (long long)(left.it_value.tv_sec / 60), 242 (int)(left.it_value.tv_sec % 60)); 243 } 244 dprintf(STDERR_FILENO, "\n"); 245 } 246 247 void 248 bye(int signo) 249 { 250 251 if (!no_timeout) 252 warnx("timeout"); 253 _exit(1); 254 } 255