desx.cpp

Go to the documentation of this file.

/*
* DES
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
 
#include <botan/desx.h>
#include <botan/internal/xor_buf.h>
 
namespace Botan {
 
/*
* DESX Encryption
*/
void DESX::encrypt_n(const byte in[], byte out[], size_t blocks) const
   {
   for(size_t i = 0; i != blocks; ++i)
      {
      xor_buf(out, in, &K1[0], BLOCK_SIZE);
      des.encrypt(out);
      xor_buf(out, &K2[0], BLOCK_SIZE);
 
      in += BLOCK_SIZE;
      out += BLOCK_SIZE;
      }
   }
 
/*
* DESX Decryption
*/
void DESX::decrypt_n(const byte in[], byte out[], size_t blocks) const
   {
   for(size_t i = 0; i != blocks; ++i)
      {
      xor_buf(out, in, &K2[0], BLOCK_SIZE);
      des.decrypt(out);
      xor_buf(out, &K1[0], BLOCK_SIZE);
 
      in += BLOCK_SIZE;
      out += BLOCK_SIZE;
      }
   }
 
/*
* DESX Key Schedule
*/
void DESX::key_schedule(const byte key[], size_t)
   {
   K1.copy(key, 8);
   des.set_key(key + 8, 8);
   K2.copy(key + 16, 8);
   }
 
}