/*

* Block Cipher Cascade

* (C) 2010 Jack Lloyd

*

* Botan is released under the Simplified BSD License (see license.txt)

*/

#ifndef BOTAN_CASCADE_H_

#define BOTAN_CASCADE_H_

#include <botan/block_cipher.h>

namespace Botan {

/**

* Block Cipher Cascade

*/

class Cascade_Cipher final : public BlockCipher

   {

   public:

      void encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override;

      void decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override;

      size_t block_size() const override { return m_block_size; }

      Key_Length_Specification key_spec() const override

         {

         return Key_Length_Specification(m_cipher1->maximum_keylength() +

                                         m_cipher2->maximum_keylength());

         }

      void clear() override;

      std::string name() const override;

      std::unique_ptr<BlockCipher> new_object() const override;

      /**

      * Create a cascade of two block ciphers

      * @param cipher1 the first cipher

      * @param cipher2 the second cipher

      */

      Cascade_Cipher(std::unique_ptr<BlockCipher> cipher1,

                     std::unique_ptr<BlockCipher> cipher2);

      Cascade_Cipher(const Cascade_Cipher&) = delete;

      Cascade_Cipher& operator=(const Cascade_Cipher&) = delete;

   private:

      void key_schedule(const uint8_t[], size_t) override;

      std::unique_ptr<BlockCipher> m_cipher1, m_cipher2;

      size_t m_block_size;

   };

}

#endif