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 */
encrypt_n(const uint8_t in[],uint8_t out[],size_t blocks) const16 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 */
decrypt_n(const uint8_t in[],uint8_t out[],size_t blocks) const48 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 */
key_schedule(const uint8_t key[],size_t length)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 */
name() const97 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 */
clone() const107 BlockCipher* Lion::clone() const
108 {
109 return new Lion(m_hash->clone(), m_cipher->clone(), block_size());
110 }
111
112 /*
113 * Clear memory of sensitive data
114 */
clear()115 void Lion::clear()
116 {
117 zap(m_key1);
118 zap(m_key2);
119 m_hash->clear();
120 m_cipher->clear();
121 }
122
123 /*
124 * Lion Constructor
125 */
Lion(HashFunction * hash,StreamCipher * cipher,size_t bs)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 }
139