CnC_Remastered_Collection/REDALERT/BLOWFISH.H
PG-SteveT 03416d24e1 Initial Source Code commit
Initial commit of original Tiberian Dawn and Red Alert source code converted to build as DLLs, and compatible with the release version of Command & Conquer Remastered.
2020-05-27 12:16:20 -07:00

115 lines
4.7 KiB
C++

//
// Copyright 2020 Electronic Arts Inc.
//
// TiberianDawn.DLL and RedAlert.dll and corresponding source code 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 3 of the License, or (at your option) any later version.
// TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed
// in the hope that it will be useful, but with permitted additional restrictions
// under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT
// distributed with this program. You should have received a copy of the
// GNU General Public License along with permitted additional restrictions
// with this program. If not, see https://github.com/electronicarts/CnC_Remastered_Collection
/* $Header: /CounterStrike/BLOWFISH.H 1 3/03/97 10:24a Joe_bostic $ */
/***********************************************************************************************
*** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S ***
***********************************************************************************************
* *
* Project Name : Command & Conquer *
* *
* File Name : BLOWFISH.H *
* *
* Programmer : Joe L. Bostic *
* *
* Start Date : 04/14/96 *
* *
* Last Update : April 14, 1996 [JLB] *
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#ifndef BLOWFISH_H
#define BLOWFISH_H
#include <limits.h>
/*
** The "bool" integral type was defined by the C++ committee in
** November of '94. Until the compiler supports this, use the following
** definition.
*/
#ifndef __BORLANDC__
#ifndef TRUE_FALSE_DEFINED
#define TRUE_FALSE_DEFINED
enum {false=0,true=1};
typedef int bool;
#endif
#endif
/*
** This engine will process data blocks by encryption and decryption.
** The "Blowfish" algorithm is in the public domain. It uses
** a Feistal network (similar to IDEA). It has no known
** weaknesses, but is still relatively new. Blowfish is particularly strong
** against brute force attacks. It is also quite strong against linear and
** differential cryptanalysis. Its weakness is that it takes a relatively
** long time to set up with a new key (1/100th of a second on a P6-200).
** The time to set up a key is equivalent to encrypting 4240 bytes.
*/
class BlowfishEngine {
public:
BlowfishEngine(void) : IsKeyed(false) {}
~BlowfishEngine(void);
void Submit_Key(void const * key, int length);
int Encrypt(void const * plaintext, int length, void * cyphertext);
int Decrypt(void const * cyphertext, int length, void * plaintext);
/*
** This is the maximum key length supported.
*/
enum {MAX_KEY_LENGTH=56};
private:
bool IsKeyed;
void Sub_Key_Encrypt(unsigned long & left, unsigned long & right);
void Process_Block(void const * plaintext, void * cyphertext, unsigned long const * ptable);
void Initialize_Tables(void);
enum {
ROUNDS = 16, // Feistal round count (16 is standard).
BYTES_PER_BLOCK=8 // The number of bytes in each cypher block (don't change).
};
/*
** Initialization data for sub keys. The initial values are constant and
** filled with a number generated from pi. Thus they are not random but
** they don't hold a weak pattern either.
*/
static unsigned long const P_Init[(int)ROUNDS+2];
static unsigned long const S_Init[4][UCHAR_MAX+1];
/*
** Permutation tables for encryption and decryption.
*/
unsigned long P_Encrypt[(int)ROUNDS+2];
unsigned long P_Decrypt[(int)ROUNDS+2];
/*
** S-Box tables (four).
*/
unsigned long bf_S[4][UCHAR_MAX+1];
};
#endif