DES.h

/*
    DES.h - Library for DES and 3DES encryption and decryption
    Ported to the Arduino platform 2013 by Tim Riemann
   
    Original version taken from the AVR-Crypto-Lib
    (http://www.das-labor.org/wiki/AVR-Crypto-Lib)
    Copyright (C) 2006-2010  Daniel Otte (daniel.otte@rub.de)

    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 3 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, see <http://www.gnu.org/licenses/>.
*/
#ifndef DES_h
#define DES_h

#include "DES_config.h"

/* the FIPS 46-3 (1999-10-25) name for triple DES is triple data encryption algorithm so TDEA.
 * Also we only implement the three key mode  */

#define tdea_enc tdes_enc
#define tdea_dec tdes_dec

class DES
{
    public:
        void encrypt(void* out, const void* in, const void* key);
        
        void decrypt(void* out, const void* in, const uint8_t* key);
        
        void tripleEncrypt(void* out, void* in, const void* key);

        void tripleDecrypt(void* out, void* in, const uint8_t* key);
        
        DES();
        
        void init(const void* m_key,unsigned long long int IVCl);
        
        void init(const void* m_key);
        
        void change_key(const void* m_key);
        
        void set_IV(unsigned long long int IVCl);
        
        void get_IV(byte *out);
        
        unsigned long long int get_IV_int();
        
        void iv_inc();
        
        byte* get_key();
        
        int get_size();
        
         void set_size(int sizel);
        
        void calc_size_n_pad(int p_size);
        
        void padPlaintext(void* in,byte* out);
        
        bool CheckPad(byte* in,int size);
        
        void tdesCbcEncipher(byte* in,byte* out);
        
        void tdesCbcDecipher(byte* in,byte* out);
        
        void printArray(byte output[],bool p_pad = true);
        
        void printArray(byte output[],int sizel);
        
        void do_3des_encrypt(byte *plain,int size_p,byte *cipher,const void *key, bool inc = false);
    
    void do_3des_decrypt(byte *cipher,int size_c,byte *plain,const void *key, unsigned long long int ivl);
        #if defined(DES_LINUX)

            double millis();
        #endif
    private:
        void permute(const uint8_t *ptable, const uint8_t *in, uint8_t *out);
        
        void changeendian32(uint32_t * a);
        
        inline void shiftkey(uint8_t *key);
        
        inline void shiftkey_inv(uint8_t *key);
        
        inline uint64_t splitin6bitwords(uint64_t a);
        
        inline uint8_t substitute(uint8_t a, uint8_t * sbp);
        
        uint32_t des_f(uint32_t r, uint8_t* kr);
        byte key[24];
        unsigned long long int IVC;
        byte iv[8];
        int pad;
        int size;
        #if defined(DES_LINUX)
            timeval tv;
        #endif
            
        byte arr_pad[7];
};

#endif