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/* vi: set sw=4 ts=4: */
/*
* vlock implementation for busybox
*
* Copyright (C) 2000 by spoon <spoon@ix.netcom.com>
* Written by spoon <spon@ix.netcom.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/* Shoutz to Michael K. Johnson <johnsonm@redhat.com>, author of the
* original vlock. I snagged a bunch of his code to write this
* minimalistic vlock.
*/
/* Fixed by Erik Andersen to do passwords the tinylogin way...
* It now works with md5, sha1, etc passwords. */
#include <stdio.h>
#include <stdlib.h>
#include <sys/vt.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <termios.h>
#include "busybox.h"
static struct passwd *pw;
static struct vt_mode ovtm;
static struct termios oterm;
static int vfd;
static int o_lock_all = 0;
#ifdef CONFIG_FEATURE_SHADOWPASSWDS
static struct spwd *spw;
/* getspuid - get a shadow entry by uid */
static struct spwd *getspuid(uid_t uid)
{
struct spwd *sp;
struct passwd *mypw;
if ((mypw = getpwuid(getuid())) == NULL) {
return (NULL);
}
setspent();
while ((sp = getspent()) != NULL) {
if (strcmp(mypw->pw_name, sp->sp_namp) == 0)
break;
}
endspent();
return (sp);
}
#endif
static void release_vt(int signo)
{
if (!o_lock_all)
ioctl(vfd, VT_RELDISP, 1);
else
ioctl(vfd, VT_RELDISP, 0);
}
static void acquire_vt(int signo)
{
ioctl(vfd, VT_RELDISP, VT_ACKACQ);
}
static void restore_terminal(void)
{
ioctl(vfd, VT_SETMODE, &ovtm);
tcsetattr(STDIN_FILENO, TCSANOW, &oterm);
}
extern int vlock_main(int argc, char **argv)
{
sigset_t sig;
struct sigaction sa;
struct vt_mode vtm;
int times = 0;
struct termios term;
if (argc > 2) {
bb_show_usage();
}
if (argc == 2) {
if (strncmp(argv[1], "-a", 2)) {
bb_show_usage();
} else {
o_lock_all = 1;
}
}
if ((pw = getpwuid(getuid())) == NULL) {
bb_error_msg_and_die("no password for uid %d\n", getuid());
}
#ifdef CONFIG_FEATURE_SHADOWPASSWDS
if ((strcmp(pw->pw_passwd, "x") == 0)
|| (strcmp(pw->pw_passwd, "*") == 0)) {
if ((spw = getspuid(getuid())) == NULL) {
bb_error_msg_and_die("could not read shadow password for uid %d: %s\n",
getuid(), strerror(errno));
}
if (spw->sp_pwdp) {
pw->pw_passwd = spw->sp_pwdp;
}
}
#endif /* CONFIG_FEATURE_SHADOWPASSWDS */
if (pw->pw_passwd[0] == '!' || pw->pw_passwd[0] == '*') {
bb_error_msg_and_die("Account disabled for uid %d\n", getuid());
}
/* we no longer need root privs */
setuid(getuid());
setgid(getgid());
if ((vfd = open("/dev/tty", O_RDWR)) < 0) {
bb_error_msg_and_die("/dev/tty");
};
if (ioctl(vfd, VT_GETMODE, &vtm) < 0) {
bb_error_msg_and_die("/dev/tty");
};
/* mask a bunch of signals */
sigprocmask(SIG_SETMASK, NULL, &sig);
sigdelset(&sig, SIGUSR1);
sigdelset(&sig, SIGUSR2);
sigaddset(&sig, SIGTSTP);
sigaddset(&sig, SIGTTIN);
sigaddset(&sig, SIGTTOU);
sigaddset(&sig, SIGHUP);
sigaddset(&sig, SIGCHLD);
sigaddset(&sig, SIGQUIT);
sigaddset(&sig, SIGINT);
sigemptyset(&(sa.sa_mask));
sa.sa_flags = SA_RESTART;
sa.sa_handler = release_vt;
sigaction(SIGUSR1, &sa, NULL);
sa.sa_handler = acquire_vt;
sigaction(SIGUSR2, &sa, NULL);
/* need to handle some signals so that we don't get killed by them */
sa.sa_handler = SIG_IGN;
sigaction(SIGHUP, &sa, NULL);
sigaction(SIGQUIT, &sa, NULL);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGTSTP, &sa, NULL);
ovtm = vtm;
vtm.mode = VT_PROCESS;
vtm.relsig = SIGUSR1;
vtm.acqsig = SIGUSR2;
ioctl(vfd, VT_SETMODE, &vtm);
tcgetattr(STDIN_FILENO, &oterm);
term = oterm;
term.c_iflag &= ~BRKINT;
term.c_iflag |= IGNBRK;
term.c_lflag &= ~ISIG;
term.c_lflag &= ~(ECHO | ECHOCTL);
tcsetattr(STDIN_FILENO, TCSANOW, &term);
do {
char *pass, *crypt_pass;
char prompt[100];
if (o_lock_all) {
printf("All Virtual Consoles locked.\n");
} else {
printf("This Virtual Console locked.\n");
}
fflush(stdout);
snprintf(prompt, 100, "%s's password: ", pw->pw_name);
if ((pass = bb_askpass(0, prompt)) == NULL) {
restore_terminal();
bb_perror_msg_and_die("password");
}
crypt_pass = pw_encrypt(pass, pw->pw_passwd);
if (strncmp(crypt_pass, pw->pw_passwd, sizeof(crypt_pass)) == 0) {
memset(pass, 0, strlen(pass));
memset(crypt_pass, 0, strlen(crypt_pass));
restore_terminal();
return 0;
}
memset(pass, 0, strlen(pass));
memset(crypt_pass, 0, strlen(crypt_pass));
if (isatty(STDIN_FILENO) == 0) {
restore_terminal();
bb_perror_msg_and_die("isatty");
}
sleep(++times);
printf("Password incorrect.\n");
if (times >= 3) {
sleep(15);
times = 2;
}
} while (1);
}
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/
|
