snes9xgx/source/smb/DES.h
dborth 65984b9102 [What Was New 004 - August 5, 2008]
- added: option to disable AA filtering 
         (snes graphics 'crisper', AA now default OFF)
- added: mapped zooming and turbo mode to classic controller
- added: preliminary usb support (loading)
- changed: sram and freezes now saved by filename, not internal romname. 
           If you have multiple versions of the same game, you can now have 
           srams and freezes for each version. A prompt to convert to the 
           new naming is provided for sram only.
- changed: by default, autoload/save sram and freeze enabled
2008-10-16 01:52:18 +00:00

180 lines
7.9 KiB
C

#ifndef AUTH_DES_H
#define AUTH_DES_H
/* ========================================================================== **
*
* DES.h
*
* Copyright:
* Copyright (C) 2003, 2004 by Christopher R. Hertel
*
* Email: crh@ubiqx.mn.org
*
* $Id: DES.h,v 0.5 2004/05/30 02:31:47 crh Exp $
*
* -------------------------------------------------------------------------- **
*
* Description:
*
* Implements DES encryption, but not decryption.
* DES is used to create LM password hashes and both LM and NTLM Responses.
*
* -------------------------------------------------------------------------- **
*
* License:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* -------------------------------------------------------------------------- **
*
* Notes:
*
* This implementation was created by studying many existing examples
* found in Open Source, in the public domain, and in various documentation.
* The SMB protocol makes minimal use of the DES function, so this is a
* minimal implementation. That which is not required has been removed.
*
* The SMB protocol uses the DES algorithm as a hash function, not an
* encryption function. The auth_DEShash() implemented here is a one-way
* function. The reverse is not implemented in this module. Also, there
* is no attempt at making this either fast or efficient. There is no
* need, as the auth)DEShash() function is used for generating the LM
* Response from a 7-byte key and an 8-byte challenge. It is not intended
* for use in encrypting large blocks of data or data streams.
*
* As stated above, this implementation is based on studying existing work
* in the public domain or under Open Source (specifically LGPL) license.
* The code, however, is written from scratch. Obviously, I make no claim
* with regard to those earlier works (except to claim that I am grateful
* to the previous implementors whose work I studied). See the list of
* references below for resources I used.
*
* References:
* I read through the libmcrypt code to see how they put the pieces
* together. See: http://mcrypt.hellug.gr/
* Libmcrypt is available under the terms of the LGPL.
*
* The libmcrypt implementation includes the following credits:
* written 12 Dec 1986 by Phil Karn, KA9Q; large sections adapted
* from the 1977 public-domain program by Jim Gillogly
* Modified for additional speed - 6 December 1988 Phil Karn
* Modified for parameterized key schedules - Jan 1991 Phil Karn
* modified in order to use the libmcrypt API by Nikos Mavroyanopoulos
* All modifications are placed under the license of libmcrypt.
*
* See also Phil Karn's privacy and security page:
* http://www.ka9q.net/privacy.html
*
* I relied heavily upon:
* Applied Cryptography, Second Edition:
* Protocols, Algorithms, and Source Code in C
* by Bruce Schneier. ISBN 0-471-11709-9, John Wiley & Sons, Inc., 1996
* Particularly Chapter 12.
*
* Here's one more DES resource, which I found quite helpful (aside from
* the Clinton jokes):
* http://www.aci.net/kalliste/des.htm
*
* Finally, the use of DES in SMB is covered in:
* Implementing CIFS - the Common Internet File System
* by your truly. ISBN 0-13-047116-X, Prentice Hall PTR., August 2003
* Section 15.3, in particular.
* (Online at: http://ubiqx.org/cifs/SMB.html#SMB.8.3)
*
* ========================================================================== **
*/
//#include "auth_common.h"
#include <stdio.h>
typedef unsigned char uchar;
typedef unsigned char uint8_t;
/* -------------------------------------------------------------------------- **
* Functions:
*/
uchar *auth_DESkey8to7( uchar *dst, const uchar *key );
/* ------------------------------------------------------------------------ **
* Compress an 8-byte DES key to its 7-byte form.
*
* Input: dst - Pointer to a memory location (minimum 7 bytes) to accept
* the compressed key.
* key - Pointer to an 8-byte DES key. See the notes below.
*
* Output: A pointer to the compressed key (same as <dst>) or NULL if
* either <src> or <dst> were NULL.
*
* Notes: There are no checks done to ensure that <dst> and <key> point
* to sufficient space. Please be carefull.
*
* The two pointers, <dst> and <key> may point to the same
* memory location. Internally, a temporary buffer is used and
* the results are copied back to <dst>.
*
* The DES algorithm uses 8 byte keys by definition. The first
* step in the algorithm, however, involves removing every eigth
* bit to produce a 56-bit key (seven bytes). SMB authentication
* skips this step and uses 7-byte keys. The <auth_DEShash()>
* algorithm in this module expects 7-byte keys. This function
* is used to convert an 8-byte DES key into a 7-byte SMB DES key.
*
* ------------------------------------------------------------------------ **
*/
uchar *auth_DEShash( uchar *dst, const uchar *key, const uchar *src );
/* ------------------------------------------------------------------------ **
* DES encryption of the input data using the input key.
*
* Input: dst - Destination buffer. It *must* be at least eight bytes
* in length, to receive the encrypted result.
* key - Encryption key. Exactly seven bytes will be used.
* If your key is shorter, ensure that you pad it to seven
* bytes.
* src - Source data to be encrypted. Exactly eight bytes will
* be used. If your source data is shorter, ensure that
* you pad it to eight bytes.
*
* Output: A pointer to the encrpyted data (same as <dst>).
*
* Notes: In SMB, the DES function is used as a hashing function rather
* than an encryption/decryption tool. When used for generating
* the LM hash the <src> input is the known value "KGS!@#$%" and
* the key is derived from the password entered by the user.
* When used to generate the LM or NTLM response, the <key> is
* derived from the LM or NTLM hash, and the challenge is used
* as the <src> input.
* See: http://ubiqx.org/cifs/SMB.html#SMB.8.3
*
* - This function is called "DEShash" rather than just "DES"
* because it is only used for creating LM hashes and the
* LM/NTLM responses. For all practical purposes, however, it
* is a full DES encryption implementation.
*
* - This DES implementation does not need to be fast, nor is a
* DES decryption function needed. The goal is to keep the
* code small, simple, and well documented.
*
* - The input values are copied and refiddled within the module
* and the result is not written to <dst> until the very last
* step, so it's okay if <dst> points to the same memory as
* <key> or <src>.
*
* ------------------------------------------------------------------------ **
*/
/* ========================================================================== */
#endif /* AUTH_DES_H */