NetBSD/usr.bin/lock/lock.c

317 lines
8.1 KiB
C

/* $NetBSD: lock.c,v 1.23 2004/03/17 17:54:25 christos Exp $ */
/*
* 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__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
__RCSID("$NetBSD: lock.c,v 1.23 2004/03/17 17:54:25 christos Exp $");
#endif /* not lint */
/*
* Lock a terminal up until the given key is entered, until the root
* password 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/time.h>
#include <signal.h>
#include <ctype.h>
#include <err.h>
#include <pwd.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#ifdef SKEY
#include <skey.h>
#endif
#define TIMEOUT 15
int main __P((int, char **));
static void bye(int) __attribute__((__noreturn__));
static void hi(int);
static void quit(int) __attribute__((__noreturn__));
#ifdef SKEY
static int skey_auth(const char *);
#endif
static struct timeval timeout;
static struct timeval zerotime;
static struct termios tty, ntty;
static int notimeout; /* no timeout at all */
static long nexttime; /* keep the timeout time */
int
main(int argc, char **argv)
{
struct passwd *pw;
struct timeval timval;
struct itimerval ntimer, otimer;
struct tm *timp;
time_t curtime;
int ch, usemine;
long sectimeout;
char *ap, *mypw, *ttynam;
const char *tzn;
uid_t uid = getuid();
char hostname[MAXHOSTNAMELEN + 1], s[BUFSIZ], s1[BUFSIZ];
if ((pw = getpwuid(getuid())) == NULL)
errx(1, "unknown uid %lu.", (u_long)uid);
if (setuid(uid) == -1) /* discard privs */
err(1, "setuid failed");
notimeout = 0;
sectimeout = TIMEOUT;
mypw = NULL;
usemine = 0;
while ((ch = getopt(argc, argv, "npt:")) != -1)
switch ((char)ch) {
case 'n':
notimeout = 1;
break;
case 't':
if (((sectimeout = strtol(optarg, &ap, 0)) == LONG_MAX
|| sectimeout == LONG_MIN)
&& errno == ERANGE)
err(1, "illegal timeout value: %s", optarg);
if (optarg == ap || *ap || sectimeout <= 0)
errx(1, "illegal timeout value: %s", optarg);
if (sectimeout >= INT_MAX / 60)
errx(1, "too large timeout value: %ld",
sectimeout);
break;
case 'p':
usemine = 1;
mypw = strdup(pw->pw_passwd);
if (!mypw)
err(1, "strdup");
break;
case '?':
default:
(void)fprintf(stderr,
"Usage: %s [-p] [-t timeout]\n", getprogname());
exit(1);
}
timeout.tv_sec = (int)sectimeout * 60;
if (tcgetattr(STDIN_FILENO, &tty) < 0) /* get information for header */
err(1, "tcgetattr failed");
gethostname(hostname, sizeof(hostname));
hostname[sizeof(hostname) - 1] = '\0';
if (!(ttynam = ttyname(STDIN_FILENO)))
err(1, "ttyname failed");
if (gettimeofday(&timval, NULL) == -1)
err(1, "gettimeofday failed");
curtime = timval.tv_sec;
nexttime = timval.tv_sec + ((int)sectimeout * 60);
timp = localtime(&curtime);
ap = asctime(timp);
#ifdef __SVR4
tzn = tzname[0];
#else
tzn = timp->tm_zone;
#endif
if (signal(SIGINT, quit) == SIG_ERR)
err(1, "signal failed");
if (signal(SIGQUIT, quit) == SIG_ERR)
err(1, "signal failed");
ntty = tty; ntty.c_lflag &= ~ECHO;
if (tcsetattr(STDIN_FILENO, TCSADRAIN, &ntty) == -1)
err(1, "tcsetattr");
if (!mypw) {
/* 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("\alock: passwords didn't match.\n");
(void)tcsetattr(STDIN_FILENO, TCSADRAIN, &tty);
exit(1);
}
s[0] = '\0';
mypw = s1;
}
/* set signal handlers */
if (signal(SIGINT, hi) == SIG_ERR)
err(1, "signal failed");
if (signal(SIGQUIT, hi) == SIG_ERR)
err(1, "signal failed");
if (signal(SIGTSTP, hi) == SIG_ERR)
err(1, "signal failed");
if (notimeout) {
if (signal(SIGALRM, hi) == SIG_ERR)
err(1, "signal failed");
(void)printf("lock: %s on %s. no timeout.\n"
"time now is %.20s%s%s",
ttynam, hostname, ap, tzn, ap + 19);
}
else {
if (signal(SIGALRM, bye) == SIG_ERR)
err(1, "signal failed");
ntimer.it_interval = zerotime;
ntimer.it_value = timeout;
if (setitimer(ITIMER_REAL, &ntimer, &otimer) == -1)
err(1, "setitimer failed");
/* header info */
(void)printf("lock: %s on %s. timeout in %ld minutes\n"
"time now is %.20s%s%s",
ttynam, hostname, sectimeout, ap, tzn, ap + 19);
}
for (;;) {
(void)printf("Key: ");
if (!fgets(s, sizeof(s), stdin)) {
clearerr(stdin);
hi(0);
goto tryagain;
}
if (usemine) {
s[strlen(s) - 1] = '\0';
#ifdef SKEY
if (strcasecmp(s, "s/key") == 0) {
if (skey_auth(pw->pw_name))
break;
}
#endif
if (!strcmp(mypw, crypt(s, mypw)))
break;
}
else if (!strcmp(s, s1))
break;
(void)printf("\a\n");
tryagain:
if (tcsetattr(STDIN_FILENO, TCSADRAIN, &ntty) == -1
&& errno != EINTR)
err(1, "tcsetattr failed");
}
quit(0);
/* NOTREACHED */
return 0;
}
#ifdef SKEY
/*
* We can't use libskey's skey_authenticate() since it
* handles signals in a way that's inappropriate
* for our needs. Instead we roll our own.
*/
static int
skey_auth(const char *user)
{
char s[128];
const char *ask;
int ret = 0;
if (!skey_haskey(user) && (ask = skey_keyinfo(user))) {
(void)printf("\n[%s]\nResponse: ", ask);
if (!fgets(s, sizeof(s), stdin) || *s == '\n')
clearerr(stdin);
else {
s[strlen(s) - 1] = '\0';
if (skey_passcheck(user, s) != -1)
ret = 1;
}
} else
(void)printf("Sorry, you have no s/key.\n");
return ret;
}
#endif
static void
hi(dummy)
int dummy;
{
struct timeval timval;
if (notimeout)
(void)printf("lock: type in the unlock key.\n");
else {
if (gettimeofday(&timval, NULL) == -1)
err(1, "gettimeofday failed");
(void)printf("lock: type in the unlock key. "
"timeout in %ld:%ld minutes\n",
(nexttime - timval.tv_sec) / 60,
(nexttime - timval.tv_sec) % 60);
}
}
static void
quit(int dummy)
{
(void)putchar('\n');
(void)tcsetattr(STDIN_FILENO, TCSADRAIN, &tty);
exit(0);
}
static void
bye(int dummy)
{
(void)tcsetattr(STDIN_FILENO, TCSADRAIN, &tty);
(void)printf("lock: timeout\n");
exit(1);
}