deb-mbse/mbsebbs/encrypt.c

/*****************************************************************************
 *
 * $Id$
 * Purpose ...............: MBSE BBS Shadow Password Suite
 * Original Source .......: Shadow Password Suite
 * Original Copyright ....: Julianne Frances Haugh and others.
 *
 *****************************************************************************
 * Copyright (C) 1997-2001
 *   
 * Michiel Broek		FIDO:		2:280/2802
 * Beekmansbos 10
 * 1971 BV IJmuiden
 * the Netherlands
 *
 * This file is part of MBSE BBS.
 *
 * This BBS 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, or (at your option) any
 * later version.
 *
 * MBSE BBS 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 MBSE BBS; see the file COPYING.  If not, write to the Free
 * Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *****************************************************************************/

/*
 * Copyright 1990 - 1993, Julianne Frances Haugh
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of Julianne F. Haugh nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "../config.h"
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#ifdef	_XOPEN_CRYPT
#include <crypt.h>
#endif
#include "encrypt.h"

#ifdef MD5_CRYPT
extern	char	*md5_crypt();
#endif


char *pw_encrypt(const char *clear, const char *salt)
{
	static	char	cipher[128];
	char	*cp;
#ifdef SW_CRYPT
	static	int	count;
#endif

#ifdef MD5_CRYPT
	/*
	 * If the salt string from the password file or from crypt_make_salt()
	 * begins with the magic string, use the new algorithm.
	 */
	if (strncmp(salt, "$1$", 3) == 0)
		return md5_crypt(clear, salt);
#endif

#ifdef	SW_CRYPT
	/*
	 * Copy over the salt.  It is always the first two
	 * characters of the string.
	 */

	cipher[0] = salt[0];
	cipher[1] = salt[1];
	cipher[2] = '\0';

	/*
	 * Loop up to ten times on the cleartext password.
	 * This is because the input limit for passwords is
	 * 80 characters.
	 *
	 * The initial salt is that provided by the user, or the
	 * one generated above.  The subsequent salts are gotten
	 * from the first two characters of the previous encrypted
	 * block of characters.
	 */

	for (count = 0;count < 10;count++) {
		cp = crypt (clear, salt);
		if (!cp) {
			perror("crypt");
			exit(1);
		}
		if (strlen(cp) != 13)
			return cp;
		strcat (cipher, cp + 2);
		salt = cipher + 11 * count + 2;

		if (strlen (clear) > 8)
			clear += 8;
		else
			break;
	}
#else
	cp = crypt (clear, salt);
	if (!cp) {
                /*
                 * Single Unix Spec: crypt() may return a null pointer,
                 * and set errno to indicate an error.  The caller doesn't
                 * expect us to return NULL, so...
                 */
                perror("crypt");
                exit(1);
        }
	if (strlen(cp) != 13)
		return cp;  /* nonstandard crypt() in libc, better bail out */
	strcpy (cipher, cp);

#ifdef	DOUBLESIZE
	if (strlen (clear) > 8) {
		cp = crypt (clear + 8, salt);
		if (!cp) {
		    perror("crypt");
		    exit(1);
		}
		strcat (cipher, cp + 2);
	}
#endif	/* DOUBLESIZE */
#endif	/* SW_CRYPT */
	return cipher;
}