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/*
* Lion
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
#ifndef BOTAN_LION_H__
#define BOTAN_LION_H__
#include <botan/block_cipher.h>
#include <botan/stream_cipher.h>
#include <botan/hash.h>
namespace Botan {
/**
* Lion is a block cipher construction designed by Ross Anderson and
* Eli Biham, described in "Two Practical and Provably Secure Block
* Ciphers: BEAR and LION". It has a variable block size and is
* designed to encrypt very large blocks (up to a megabyte)
* http://www.cl.cam.ac.uk/~rja14/Papers/bear-lion.pdf
*/
class BOTAN_DLL Lion : public BlockCipher
{
public:
void encrypt_n(const byte in[], byte out[], size_t blocks) const;
void decrypt_n(const byte in[], byte out[], size_t blocks) const;
size_t block_size() const { return BLOCK_SIZE; }
Key_Length_Specification key_spec() const
{
return Key_Length_Specification(2, 2*hash->output_length(), 2);
}
void clear();
std::string name() const;
BlockCipher* clone() const;
/**
* @param hash the hash to use internally
* @param cipher the stream cipher to use internally
* @param block_size the size of the block to use
*/
Lion(HashFunction* hash,
StreamCipher* cipher,
size_t block_size);
Lion(const Lion&) = delete;
Lion& operator=(const Lion&) = delete;
~Lion() { delete hash; delete cipher; }
private:
void key_schedule(const byte[], size_t);
const size_t BLOCK_SIZE, LEFT_SIZE, RIGHT_SIZE;
HashFunction* hash;
StreamCipher* cipher;
secure_vector<byte> key1, key2;
};
}
#endif
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