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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -*-
*
* Copyright (C) 2005-2006 William Jon McCann <mccann@jhu.edu>
*
* 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.
*
* Authors: William Jon McCann <mccann@jhu.edu>
*
*/
#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <termios.h>
#include <glib/gi18n.h>
#include <gtk/gtk.h>
#include "gs-auth.h"
#include "setuid.h"
/* Initializations that potentially take place as a priveleged user:
If the executable is setuid root, then these initializations
are run as root, before discarding privileges.
*/
static gboolean
privileged_initialization (void)
{
gboolean ret;
char *nolock_reason;
char *orig_uid;
char *uid_message;
#ifndef NO_LOCKING
/* before hack_uid () for proper permissions */
gs_auth_priv_init ();
#endif /* NO_LOCKING */
ret = hack_uid (&nolock_reason,
&orig_uid,
&uid_message);
if (nolock_reason)
{
g_warning ("Locking disabled: %s", nolock_reason);
}
if (uid_message && gs_auth_get_verbose ())
{
g_print ("Modified UID: %s", uid_message);
}
g_free (nolock_reason);
g_free (orig_uid);
g_free (uid_message);
return ret;
}
/* Figure out what locking mechanisms are supported.
*/
static gboolean
lock_initialization (char **nolock_reason)
{
if (nolock_reason)
{
*nolock_reason = NULL;
}
#ifdef NO_LOCKING
if (nolock_reason)
{
*nolock_reason = g_strdup ("not compiled with locking support");
}
return FALSE;
#else /* !NO_LOCKING */
/* Finish initializing locking, now that we're out of privileged code. */
if (! gs_auth_init ())
{
if (nolock_reason)
{
*nolock_reason = g_strdup ("error getting password");
}
return FALSE;
}
/* If locking is currently enabled, but the environment indicates that
we have been launched as MDM's "Background" program, then disable
locking just in case.
*/
if (getenv ("RUNNING_UNDER_MDM"))
{
if (nolock_reason)
{
*nolock_reason = g_strdup ("running under MDM");
}
return FALSE;
}
/* If the server is XDarwin (MacOS X) then disable locking.
(X grabs only affect X programs, so you can use Command-Tab
to bring any other Mac program to the front, e.g., Terminal.)
*/
{
gboolean macos = FALSE;
#ifdef __APPLE__
/* Disable locking if *running* on Apple hardware, since we have no
reliable way to determine whether the server is running on MacOS.
Hopefully __APPLE__ means "MacOS" and not "Linux on Mac hardware"
but I'm not really sure about that.
*/
macos = TRUE;
#endif
if (macos)
{
if (nolock_reason)
{
*nolock_reason = g_strdup ("Cannot lock securely on MacOS X");
}
return FALSE;
}
}
#endif /* NO_LOCKING */
return TRUE;
}
static char *
request_password (const char *prompt)
{
char buf [255];
char *pass;
char *password;
struct termios ts0;
struct termios ts1;
tcgetattr (fileno (stdin), &ts0);
ts1 = ts0;
ts1.c_lflag &= ~ECHO;
printf ("%s", prompt);
if (tcsetattr (fileno (stdin), TCSAFLUSH, &ts1) != 0)
{
fprintf (stderr, "Could not set terminal attributes\n");
exit (1);
}
pass = fgets (buf, sizeof (buf) - 1, stdin);
tcsetattr (fileno (stdin), TCSANOW, &ts0);
if (!pass || !*pass)
{
exit (0);
}
if (pass [strlen (pass) - 1] == '\n')
{
pass [strlen (pass) - 1] = 0;
}
password = g_strdup (pass);
memset (pass, '\b', strlen (pass));
return password;
}
static gboolean
auth_message_handler (GSAuthMessageStyle style,
const char *msg,
char **response,
gpointer data)
{
gboolean ret;
g_message ("Got message style %d: '%s'", style, msg);
ret = TRUE;
switch (style)
{
case GS_AUTH_MESSAGE_PROMPT_ECHO_ON:
break;
case GS_AUTH_MESSAGE_PROMPT_ECHO_OFF:
{
char *password;
password = request_password (msg);
*response = password;
}
break;
case GS_AUTH_MESSAGE_ERROR_MSG:
break;
case GS_AUTH_MESSAGE_TEXT_INFO:
break;
default:
g_assert_not_reached ();
}
return ret;
}
int
main (int argc,
char **argv)
{
GError *error = NULL;
gboolean verbose = TRUE;
char *nolock_reason = NULL;
#ifdef ENABLE_NLS
bindtextdomain (GETTEXT_PACKAGE, MATELOCALEDIR);
# ifdef HAVE_BIND_TEXTDOMAIN_CODESET
bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
# endif
textdomain (GETTEXT_PACKAGE);
#endif
if (! g_thread_supported ())
{
g_thread_init (NULL);
}
gs_auth_set_verbose (verbose);
if (! privileged_initialization ())
{
exit (1);
}
if (! gtk_init_with_args (&argc, &argv, NULL, NULL, NULL, &error))
{
fprintf (stderr, "%s", error->message);
g_error_free (error);
exit (1);
}
if (! lock_initialization (&nolock_reason))
{
if (nolock_reason)
{
g_warning ("Screen locking disabled: %s", nolock_reason);
g_free (nolock_reason);
}
exit (1);
}
again:
error = NULL;
if (gs_auth_verify_user (g_get_user_name (), g_getenv ("DISPLAY"), auth_message_handler, NULL, &error))
{
printf ("Correct!\n");
}
else
{
if (error != NULL)
{
fprintf (stderr, "ERROR: %s\n", error->message);
g_error_free (error);
}
printf ("Incorrect\n");
goto again;
}
return 0;
}
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