Botan  1.10.9
lion.h
Go to the documentation of this file.
1 /*
2 * Lion
3 * (C) 1999-2007 Jack Lloyd
4 *
5 * Distributed under the terms of the Botan license
6 */
7 
8 #ifndef BOTAN_LION_H__
9 #define BOTAN_LION_H__
10 
11 #include <botan/block_cipher.h>
12 #include <botan/stream_cipher.h>
13 #include <botan/hash.h>
14 
15 namespace Botan {
16 
17 /**
18 * Lion is a block cipher construction designed by Ross Anderson and
19 * Eli Biham, described in "Two Practical and Provably Secure Block
20 * Ciphers: BEAR and LION". It has a variable block size and is
21 * designed to encrypt very large blocks (up to a megabyte)
22 
23 * http://www.cl.cam.ac.uk/~rja14/Papers/bear-lion.pdf
24 */
25 class BOTAN_DLL Lion : public BlockCipher
26  {
27  public:
28  void encrypt_n(const byte in[], byte out[], size_t blocks) const;
29  void decrypt_n(const byte in[], byte out[], size_t blocks) const;
30 
31  size_t block_size() const { return BLOCK_SIZE; }
32 
34  {
35  return Key_Length_Specification(2, 2*hash->output_length(), 2);
36  }
37 
38  void clear();
39  std::string name() const;
40  BlockCipher* clone() const;
41 
42  /**
43  * @param hash the hash to use internally
44  * @param cipher the stream cipher to use internally
45  * @param block_size the size of the block to use
46  */
47  Lion(HashFunction* hash,
48  StreamCipher* cipher,
49  size_t block_size);
50 
51  ~Lion() { delete hash; delete cipher; }
52  private:
53  void key_schedule(const byte[], size_t);
54 
55  const size_t BLOCK_SIZE, LEFT_SIZE, RIGHT_SIZE;
56 
57  HashFunction* hash;
58  StreamCipher* cipher;
59  SecureVector<byte> key1, key2;
60  };
61 
62 }
63 
64 #endif
Key_Length_Specification key_spec() const
Definition: lion.h:33
size_t block_size
Definition: ossl_md.cpp:41
unsigned char byte
Definition: types.h:22
~Lion()
Definition: lion.h:51
size_t block_size() const
Definition: lion.h:31