/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1980, 1987, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Bob Toxen.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1987, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)lock.c 8.1 (Berkeley) 6/6/93";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Lock a terminal up until the given key is entered or the given
* interval times out.
*
* Timeout interval is by default TIMEOUT, it can be changed with
* an argument of the form -time where time is in minutes
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/signal.h>
#include <sys/consio.h>
#include <err.h>
#include <ctype.h>
#include <errno.h>
#include <paths.h>
#include <pwd.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#include <security/pam_appl.h>
#include <security/openpam.h> /* for openpam_ttyconv() */
#define TIMEOUT 15
static void quit(int);
static void bye(int);
static void hi(int);
static void usage(void);
static struct timeval timeout;
static struct timeval zerotime;
static struct termios tty, ntty;
static long nexttime; /* keep the timeout time */
static int no_timeout; /* lock terminal forever */
static int vtyunlock; /* Unlock flag and code. */
/*ARGSUSED*/
int
main(int argc, char **argv)
{
static const struct pam_conv pamc = { &openpam_ttyconv, NULL };
pam_handle_t *pamh;
struct passwd *pw;
struct itimerval ntimer, otimer;
struct tm *timp;
time_t timval;
int ch, failures, pam_err, sectimeout, usemine, vtylock;
char *ap, *ttynam, *tzn;
char hostname[MAXHOSTNAMELEN], s[BUFSIZ], s1[BUFSIZ];
openlog("lock", 0, LOG_AUTH);
pam_err = PAM_SYSTEM_ERR; /* pacify GCC */
sectimeout = TIMEOUT;
pamh = NULL;
pw = NULL;
usemine = 0;
no_timeout = 0;
vtylock = 0;
while ((ch = getopt(argc, argv, "npt:v")) != -1)
switch((char)ch) {
case 't':
if ((sectimeout = atoi(optarg)) <= 0)
errx(1, "illegal timeout value");
break;
case 'p':
usemine = 1;
if (!(pw = getpwuid(getuid())))
errx(1, "unknown uid %d", getuid());
break;
case 'n':
no_timeout = 1;
break;
case 'v':
vtylock = 1;
break;
case '?':
default:
usage();
}
timeout.tv_sec = sectimeout * 60;
if (!usemine) { /* -p with PAM or S/key needs privs */
/* discard privs */
if (setuid(getuid()) != 0)
errx(1, "setuid failed");
}
if (tcgetattr(0, &tty)) /* get information for header */
exit(1);
gethostname(hostname, sizeof(hostname));
if (!(ttynam = ttyname(0)))
errx(1, "not a terminal?");
if (strncmp(ttynam, _PATH_DEV, strlen(_PATH_DEV)) == 0)
ttynam += strlen(_PATH_DEV);
timval = time(NULL);
nexttime = timval + (sectimeout * 60);
timp = localtime(&timval);
ap = asctime(timp);
tzn = timp->tm_zone;
(void)signal(SIGINT, quit);
(void)signal(SIGQUIT, quit);
ntty = tty; ntty.c_lflag &= ~ECHO;
(void)tcsetattr(0, TCSADRAIN|TCSASOFT, &ntty);
if (usemine) {
pam_err = pam_start("lock", pw->pw_name, &pamc, &pamh);
if (pam_err != PAM_SUCCESS)
err(1, "pam_start: %s", pam_strerror(NULL, pam_err));
} else {
/* get key and check again */
(void)printf("Key: ");
if (!fgets(s, sizeof(s), stdin) || *s == '\n')
quit(0);
(void)printf("\nAgain: ");
/*
* Don't need EOF test here, if we get EOF, then s1 != s
* and the right things will happen.
*/
(void)fgets(s1, sizeof(s1), stdin);
(void)putchar('\n');
if (strcmp(s1, s)) {
(void)printf("\07lock: passwords didn't match.\n");
(void)tcsetattr(0, TCSADRAIN|TCSASOFT, &tty);
exit(1);
}
s[0] = '\0';
}
/* set signal handlers */
(void)signal(SIGINT, hi);
(void)signal(SIGQUIT, hi);
(void)signal(SIGTSTP, hi);
(void)signal(SIGALRM, bye);
ntimer.it_interval = zerotime;
ntimer.it_value = timeout;
if (!no_timeout)
setitimer(ITIMER_REAL, &ntimer, &otimer);
if (vtylock) {
/*
* If this failed, we want to err out; warn isn't good
* enough, since we don't want the user to think that
* everything is nice and locked because they got a
* "Key:" prompt.
*/
if (ioctl(0, VT_LOCKSWITCH, &vtylock) == -1) {
(void)tcsetattr(0, TCSADRAIN|TCSASOFT, &tty);
err(1, "locking vty");
}
vtyunlock = 0x2;
}
/* header info */
if (pw != NULL)
(void)printf("lock: %s using %s on %s.", pw->pw_name,
ttynam, hostname);
else
(void)printf("lock: %s on %s.", ttynam, hostname);
if (no_timeout)
(void)printf(" no timeout.");
else
(void)printf(" timeout in %d minute%s.", sectimeout,
sectimeout != 1 ? "s" : "");
if (vtylock)
(void)printf(" vty locked.");
(void)printf("\ntime now is %.20s%s%s", ap, tzn, ap + 19);
failures = 0;
for (;;) {
if (usemine) {
pam_err = pam_authenticate(pamh, 0);
if (pam_err == PAM_SUCCESS)
break;
if (pam_err != PAM_AUTH_ERR &&
pam_err != PAM_USER_UNKNOWN &&
pam_err != PAM_MAXTRIES) {
syslog(LOG_ERR, "pam_authenticate: %s",
pam_strerror(pamh, pam_err));
}
goto tryagain;
}
(void)printf("Key: ");
if (!fgets(s, sizeof(s), stdin)) {
clearerr(stdin);
hi(0);
goto tryagain;
}
if (!strcmp(s, s1))
break;
(void)printf("\07\n");
failures++;
if (getuid() == 0)
syslog(LOG_NOTICE, "%d ROOT UNLOCK FAILURE%s (%s on %s)",
failures, failures > 1 ? "S": "", ttynam, hostname);
tryagain:
if (tcgetattr(0, &ntty) && (errno != EINTR))
exit(1);
sleep(1); /* to discourage guessing */
}
if (getuid() == 0)
syslog(LOG_NOTICE, "ROOT UNLOCK ON hostname %s port %s",
hostname, ttynam);
if (usemine)
(void)pam_end(pamh, pam_err);
quit(0);
return(0); /* not reached */
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: lock [-npv] [-t timeout]\n");
exit(1);
}
static void
hi(int signo __unused)
{
time_t timval;
timval = time(NULL);
(void)printf("lock: type in the unlock key. ");
if (no_timeout) {
(void)putchar('\n');
} else {
(void)printf("timeout in %jd:%jd minutes\n",
(intmax_t)(nexttime - timval) / 60,
(intmax_t)(nexttime - timval) % 60);
}
}
static void
quit(int signo __unused)
{
(void)putchar('\n');
(void)tcsetattr(0, TCSADRAIN|TCSASOFT, &tty);
if (vtyunlock)
(void)ioctl(0, VT_LOCKSWITCH, &vtyunlock);
exit(0);
}
static void
bye(int signo __unused)
{
if (!no_timeout) {
(void)tcsetattr(0, TCSADRAIN|TCSASOFT, &tty);
if (vtyunlock)
(void)ioctl(0, VT_LOCKSWITCH, &vtyunlock);
(void)printf("lock: timeout\n");
exit(1);
}
}
