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/*
* checktoken.c
*
* An example program for CERBERUS.
* ( https://osdn.jp/projects/tomoyo/document/winf2005-en.pdf )
*
* Copyright (C) 2005-2011 NTT DATA CORPORATION
*
* Version: 2.6.0 2019/03/05
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License v2 as published by the
* Free Software Foundation.
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <pwd.h>
#include <time.h>
static const char *get_shell(void)
{
static char *shell = NULL;
if (!shell) {
struct passwd *pw = getpwuid(getuid());
shell = pw ? pw->pw_shell : "/bin/sh";
}
return shell;
}
int main(int argc, char *argv[])
{
static char buffer[1024];
static char seed[40];
int i;
int trial;
const char *shell = get_shell();
srand(time(NULL) / 30);
memset(seed, 0, sizeof(seed));
for (i = 0; i < sizeof(seed) - 1; i++)
seed[i] = (rand() % 64) + 33;
for (trial = 0; trial < 3; trial++) {
char *dp;
char *ret_ignored;
memset(buffer, 0, sizeof(buffer));
printf("Password: ");
ret_ignored = fgets(buffer, sizeof(buffer) - 1, stdin);
dp = strchr(buffer, '\n');
if (dp)
*dp = '\0';
if (!strcmp(buffer, seed)) {
if (shell)
execlp(shell, shell, NULL);
}
sleep(3);
}
printf("Authentication Failure\n");
return 0;
}
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