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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>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* 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 <sys/vt.h>
#include "libbb.h"
static void release_vt(int signo UNUSED_PARAM)
{
/* If -a, param is 0, which means:
* "no, kernel, we don't allow console switch away from us!" */
ioctl(STDIN_FILENO, VT_RELDISP, (unsigned long) !option_mask32);
}
static void acquire_vt(int signo UNUSED_PARAM)
{
/* ACK to kernel that switch to console is successful */
ioctl(STDIN_FILENO, VT_RELDISP, VT_ACKACQ);
}
int vlock_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int vlock_main(int argc UNUSED_PARAM, char **argv)
{
struct vt_mode vtm;
struct termios term;
struct termios oterm;
struct vt_mode ovtm;
uid_t uid;
struct passwd *pw;
uid = getuid();
pw = getpwuid(uid);
if (pw == NULL)
bb_error_msg_and_die("unknown uid %d", (int)uid);
opt_complementary = "=0"; /* no params! */
getopt32(argv, "a");
/* Ignore some signals so that we don't get killed by them */
bb_signals(0
+ (1 << SIGTSTP)
+ (1 << SIGTTIN)
+ (1 << SIGTTOU)
+ (1 << SIGHUP )
+ (1 << SIGCHLD) /* paranoia :) */
+ (1 << SIGQUIT)
+ (1 << SIGINT )
, SIG_IGN);
/* We will use SIGUSRx for console switch control: */
/* 1: set handlers */
signal_SA_RESTART_empty_mask(SIGUSR1, release_vt);
signal_SA_RESTART_empty_mask(SIGUSR2, acquire_vt);
/* 2: unmask them */
sig_unblock(SIGUSR1);
sig_unblock(SIGUSR2);
/* Revert stdin/out to our controlling tty
* (or die if we have none) */
xmove_fd(xopen(CURRENT_TTY, O_RDWR), STDIN_FILENO);
xdup2(STDIN_FILENO, STDOUT_FILENO);
xioctl(STDIN_FILENO, VT_GETMODE, &vtm);
ovtm = vtm;
/* "console switches are controlled by us, not kernel!" */
vtm.mode = VT_PROCESS;
vtm.relsig = SIGUSR1;
vtm.acqsig = SIGUSR2;
ioctl(STDIN_FILENO, 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 {
printf("Virtual console%s locked by %s.\n",
option_mask32 /*o_lock_all*/ ? "s" : "",
pw->pw_name);
if (correct_password(pw)) {
break;
}
bb_do_delay(FAIL_DELAY);
puts("Password incorrect");
} while (1);
ioctl(STDIN_FILENO, VT_SETMODE, &ovtm);
tcsetattr(STDIN_FILENO, TCSANOW, &oterm);
fflush_stdout_and_exit(EXIT_SUCCESS);
}
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