busybox/loginutils/vlock.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 <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;
	struct passwd *pw;

	pw = xgetpwuid(getuid());
	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_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_TCSANOW(&oterm);
	fflush_stdout_and_exit(EXIT_SUCCESS);
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3			* vlock implementation for busybox
4			*
5			* Copyright (C) 2000 by spoon <spoon@ix.netcom.com>
6			* Written by spoon <spon@ix.netcom.com>
7			*
8			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9			*/
10
11			/* Shoutz to Michael K. Johnson <johnsonm@redhat.com>, author of the
12			* original vlock. I snagged a bunch of his code to write this
13			* minimalistic vlock.
14			*/
15			/* Fixed by Erik Andersen to do passwords the tinylogin way...
16			* It now works with md5, sha1, etc passwords. */
17
18			#include <sys/vt.h>
19	niro	816	#include "libbb.h"
20	niro	532
21	niro	816	static void release_vt(int signo UNUSED_PARAM)
22	niro	532	{
23	niro	816	/* If -a, param is 0, which means:
24			* "no, kernel, we don't allow console switch away from us!" */
25			ioctl(STDIN_FILENO, VT_RELDISP, (unsigned long) !option_mask32);
26	niro	532	}
27
28	niro	816	static void acquire_vt(int signo UNUSED_PARAM)
29	niro	532	{
30	niro	816	/* ACK to kernel that switch to console is successful */
31			ioctl(STDIN_FILENO, VT_RELDISP, VT_ACKACQ);
32	niro	532	}
33
34	niro	816	int vlock_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
35			int vlock_main(int argc UNUSED_PARAM, char **argv)
36	niro	532	{
37			struct vt_mode vtm;
38			struct termios term;
39	niro	816	struct termios oterm;
40			struct vt_mode ovtm;
41			struct passwd *pw;
42	niro	532
43	niro	984	pw = xgetpwuid(getuid());
44	niro	816	opt_complementary = "=0"; /* no params! */
45			getopt32(argv, "a");
46	niro	532
47	niro	816	/* Ignore some signals so that we don't get killed by them */
48			bb_signals(0
49			+ (1 << SIGTSTP)
50			+ (1 << SIGTTIN)
51			+ (1 << SIGTTOU)
52			+ (1 << SIGHUP )
53			+ (1 << SIGCHLD) /* paranoia :) */
54			+ (1 << SIGQUIT)
55			+ (1 << SIGINT )
56			, SIG_IGN);
57	niro	532
58	niro	816	/* We will use SIGUSRx for console switch control: */
59			/* 1: set handlers */
60			signal_SA_RESTART_empty_mask(SIGUSR1, release_vt);
61			signal_SA_RESTART_empty_mask(SIGUSR2, acquire_vt);
62			/* 2: unmask them */
63			sig_unblock(SIGUSR1);
64			sig_unblock(SIGUSR2);
65	niro	532
66	niro	816	/* Revert stdin/out to our controlling tty
67			* (or die if we have none) */
68			xmove_fd(xopen(CURRENT_TTY, O_RDWR), STDIN_FILENO);
69			xdup2(STDIN_FILENO, STDOUT_FILENO);
70	niro	532
71	niro	816	xioctl(STDIN_FILENO, VT_GETMODE, &vtm);
72	niro	532	ovtm = vtm;
73	niro	816	/* "console switches are controlled by us, not kernel!" */
74	niro	532	vtm.mode = VT_PROCESS;
75			vtm.relsig = SIGUSR1;
76			vtm.acqsig = SIGUSR2;
77	niro	816	ioctl(STDIN_FILENO, VT_SETMODE, &vtm);
78	niro	532
79			tcgetattr(STDIN_FILENO, &oterm);
80			term = oterm;
81			term.c_iflag &= ~BRKINT;
82			term.c_iflag \|= IGNBRK;
83			term.c_lflag &= ~ISIG;
84			term.c_lflag &= ~(ECHO \| ECHOCTL);
85	niro	816	tcsetattr_stdin_TCSANOW(&term);
86	niro	532
87			do {
88	niro	816	printf("Virtual console%s locked by %s.\n",
89			option_mask32 /o_lock_all/ ? "s" : "",
90			pw->pw_name);
91	niro	532	if (correct_password(pw)) {
92			break;
93			}
94			bb_do_delay(FAIL_DELAY);
95			puts("Password incorrect");
96			} while (1);
97	niro	816
98			ioctl(STDIN_FILENO, VT_SETMODE, &ovtm);
99			tcsetattr_stdin_TCSANOW(&oterm);
100			fflush_stdout_and_exit(EXIT_SUCCESS);
101	niro	532	}