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 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 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 243 bye(int signo) 244 { 245 246 if (!no_timeout) 247 warnx("timeout"); 248 _exit(1); 249 } 250 251 void 252 usage(void) 253 { 254 fprintf(stderr, "usage: %s [-np] [-a style] [-t timeout]\n", 255 getprogname()); 256 exit(1); 257 } 258