Botan  2.12.1
Crypto and TLS for C++11
lion.h
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1 /*
2 * Lion
3 * (C) 1999-2007,2014 Jack Lloyd
4 *
5 * Botan is released under the Simplified BSD License (see license.txt)
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 
16 
17 namespace Botan {
18 
19 /**
20 * Lion is a block cipher construction designed by Ross Anderson and
21 * Eli Biham, described in "Two Practical and Provably Secure Block
22 * Ciphers: BEAR and LION". It has a variable block size and is
23 * designed to encrypt very large blocks (up to a megabyte)
24 
25 * https://www.cl.cam.ac.uk/~rja14/Papers/bear-lion.pdf
26 */
28  {
29  public:
30  void encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override;
31  void decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override;
32 
33  size_t block_size() const override { return m_block_size; }
34 
36  {
37  return Key_Length_Specification(2, 2*m_hash->output_length(), 2);
38  }
39 
40  void clear() override;
41  std::string name() const override;
42  BlockCipher* clone() const override;
43 
44  /**
45  * @param hash the hash to use internally
46  * @param cipher the stream cipher to use internally
47  * @param block_size the size of the block to use
48  */
50  StreamCipher* cipher,
51  size_t block_size);
52  private:
53  void key_schedule(const uint8_t[], size_t) override;
54 
55  size_t left_size() const { return m_hash->output_length(); }
56  size_t right_size() const { return m_block_size - left_size(); }
57 
58  const size_t m_block_size;
59  std::unique_ptr<HashFunction> m_hash;
60  std::unique_ptr<StreamCipher> m_cipher;
61  secure_vector<uint8_t> m_key1, m_key2;
62  };
63 
64 }
65 
66 #endif
Key_Length_Specification key_spec() const override
Definition: lion.h:35
virtual void decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const =0
int(* final)(unsigned char *, CTX *)
#define BOTAN_PUBLIC_API(maj, min)
Definition: compiler.h:31
virtual BlockCipher * clone() const =0
size_t block_size() const override
Definition: lion.h:33
virtual std::string name() const =0
virtual void clear()=0
Definition: alg_id.cpp:13
virtual void encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const =0
#define BOTAN_FUTURE_INTERNAL_HEADER(hdr)
Definition: compiler.h:139
MechanismType hash