hush/loginutils/vlock.c

121 lines
2.6 KiB
C

/* 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 "busybox.h"
#include <sys/vt.h>
static struct passwd *pw;
static struct vt_mode ovtm;
static struct termios oterm;
static int vfd;
static unsigned long o_lock_all;
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);
}
int vlock_main(int argc, char **argv)
{
sigset_t sig;
struct sigaction sa;
struct vt_mode vtm;
struct termios term;
if (argc > 2) {
bb_show_usage();
}
o_lock_all = getopt32(argc, argv, "a");
if((pw = getpwuid(getuid())) == NULL) {
bb_error_msg_and_die("unknown uid %d", getuid());
}
vfd = xopen(CURRENT_TTY, O_RDWR);
if (ioctl(vfd, VT_GETMODE, &vtm) < 0) {
bb_perror_msg_and_die("VT_GETMODE");
}
/* 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 {
printf("Virtual Console%s locked by %s.\n", (o_lock_all) ? "s" : "", pw->pw_name);
if (correct_password(pw)) {
break;
}
bb_do_delay(FAIL_DELAY);
puts("Password incorrect");
} while (1);
restore_terminal();
return 0;
}