Botan  2.7.0
Crypto and TLS for C++11
lion.cpp
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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 #include <botan/lion.h>
9 #include <botan/exceptn.h>
10 
11 namespace Botan {
12 
13 /*
14 * Lion Encryption
15 */
16 void Lion::encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const
17  {
18  verify_key_set(m_key1.empty() == false);
19 
20  const size_t LEFT_SIZE = left_size();
21  const size_t RIGHT_SIZE = right_size();
22 
23  secure_vector<uint8_t> buffer_vec(LEFT_SIZE);
24  uint8_t* buffer = buffer_vec.data();
25 
26  for(size_t i = 0; i != blocks; ++i)
27  {
28  xor_buf(buffer, in, m_key1.data(), LEFT_SIZE);
29  m_cipher->set_key(buffer, LEFT_SIZE);
30  m_cipher->cipher(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
31 
32  m_hash->update(out + LEFT_SIZE, RIGHT_SIZE);
33  m_hash->final(buffer);
34  xor_buf(out, in, buffer, LEFT_SIZE);
35 
36  xor_buf(buffer, out, m_key2.data(), LEFT_SIZE);
37  m_cipher->set_key(buffer, LEFT_SIZE);
38  m_cipher->cipher1(out + LEFT_SIZE, RIGHT_SIZE);
39 
40  in += m_block_size;
41  out += m_block_size;
42  }
43  }
44 
45 /*
46 * Lion Decryption
47 */
48 void Lion::decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const
49  {
50  verify_key_set(m_key1.empty() == false);
51 
52  const size_t LEFT_SIZE = left_size();
53  const size_t RIGHT_SIZE = right_size();
54 
55  secure_vector<uint8_t> buffer_vec(LEFT_SIZE);
56  uint8_t* buffer = buffer_vec.data();
57 
58  for(size_t i = 0; i != blocks; ++i)
59  {
60  xor_buf(buffer, in, m_key2.data(), LEFT_SIZE);
61  m_cipher->set_key(buffer, LEFT_SIZE);
62  m_cipher->cipher(in + LEFT_SIZE, out + LEFT_SIZE, RIGHT_SIZE);
63 
64  m_hash->update(out + LEFT_SIZE, RIGHT_SIZE);
65  m_hash->final(buffer);
66  xor_buf(out, in, buffer, LEFT_SIZE);
67 
68  xor_buf(buffer, out, m_key1.data(), LEFT_SIZE);
69  m_cipher->set_key(buffer, LEFT_SIZE);
70  m_cipher->cipher1(out + LEFT_SIZE, RIGHT_SIZE);
71 
72  in += m_block_size;
73  out += m_block_size;
74  }
75  }
76 
77 /*
78 * Lion Key Schedule
79 */
80 void Lion::key_schedule(const uint8_t key[], size_t length)
81  {
82  clear();
83 
84  const size_t half = length / 2;
85 
86  m_key1.resize(left_size());
87  m_key2.resize(left_size());
88  clear_mem(m_key1.data(), m_key1.size());
89  clear_mem(m_key2.data(), m_key2.size());
90  copy_mem(m_key1.data(), key, half);
91  copy_mem(m_key2.data(), key + half, half);
92  }
93 
94 /*
95 * Return the name of this type
96 */
97 std::string Lion::name() const
98  {
99  return "Lion(" + m_hash->name() + "," +
100  m_cipher->name() + "," +
101  std::to_string(block_size()) + ")";
102  }
103 
104 /*
105 * Return a clone of this object
106 */
108  {
109  return new Lion(m_hash->clone(), m_cipher->clone(), block_size());
110  }
111 
112 /*
113 * Clear memory of sensitive data
114 */
116  {
117  zap(m_key1);
118  zap(m_key2);
119  m_hash->clear();
120  m_cipher->clear();
121  }
122 
123 /*
124 * Lion Constructor
125 */
126 Lion::Lion(HashFunction* hash, StreamCipher* cipher, size_t bs) :
127  m_block_size(std::max<size_t>(2*hash->output_length() + 1, bs)),
128  m_hash(hash),
129  m_cipher(cipher)
130  {
131  if(2*left_size() + 1 > m_block_size)
132  throw Invalid_Argument(name() + ": Chosen block size is too small");
133 
134  if(!m_cipher->valid_keylength(left_size()))
135  throw Invalid_Argument(name() + ": This stream/hash combo is invalid");
136  }
137 
138 }
BlockCipher * clone() const override
Definition: lion.cpp:107
void encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override
Definition: lion.cpp:16
void clear() override
Definition: lion.cpp:115
void verify_key_set(bool cond) const
Definition: sym_algo.h:89
void zap(std::vector< T, Alloc > &vec)
Definition: secmem.h:193
void clear_mem(T *ptr, size_t n)
Definition: mem_ops.h:97
Definition: bigint.h:796
std::string to_string(const BER_Object &obj)
Definition: asn1_obj.cpp:210
size_t block_size() const override
Definition: lion.h:31
void xor_buf(uint8_t out[], const uint8_t in[], size_t length)
Definition: mem_ops.h:174
void copy_mem(T *out, const T *in, size_t n)
Definition: mem_ops.h:108
Definition: alg_id.cpp:13
std::vector< T, secure_allocator< T > > secure_vector
Definition: secmem.h:88
void decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const override
Definition: lion.cpp:48
Lion(HashFunction *hash, StreamCipher *cipher, size_t block_size)
Definition: lion.cpp:126
MechanismType hash
std::string name() const override
Definition: lion.cpp:97