1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/*
* WiderWake
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
#include <botan/wid_wake.h>
#include <botan/loadstor.h>
#include <botan/internal/xor_buf.h>
namespace Botan {
/*
* Combine cipher stream with message
*/
void WiderWake_41_BE::cipher(const byte in[], byte out[], size_t length)
{
while(length >= buffer.size() - position)
{
xor_buf(out, in, &buffer[position], buffer.size() - position);
length -= (buffer.size() - position);
in += (buffer.size() - position);
out += (buffer.size() - position);
generate(buffer.size());
}
xor_buf(out, in, &buffer[position], length);
position += length;
}
/*
* Generate cipher stream
*/
void WiderWake_41_BE::generate(size_t length)
{
u32bit R0 = state[0], R1 = state[1],
R2 = state[2], R3 = state[3],
R4 = state[4];
for(size_t i = 0; i != length; i += 8)
{
u32bit R0a;
store_be(R3, &buffer[i]);
R0a = R4 + R3; R3 += R2; R2 += R1; R1 += R0;
R0a = (R0a >> 8) ^ T[(R0a & 0xFF)];
R1 = (R1 >> 8) ^ T[(R1 & 0xFF)];
R2 = (R2 >> 8) ^ T[(R2 & 0xFF)];
R3 = (R3 >> 8) ^ T[(R3 & 0xFF)];
R4 = R0; R0 = R0a;
store_be(R3, &buffer[i + 4]);
R0a = R4 + R3; R3 += R2; R2 += R1; R1 += R0;
R0a = (R0a >> 8) ^ T[(R0a & 0xFF)];
R1 = (R1 >> 8) ^ T[(R1 & 0xFF)];
R2 = (R2 >> 8) ^ T[(R2 & 0xFF)];
R3 = (R3 >> 8) ^ T[(R3 & 0xFF)];
R4 = R0; R0 = R0a;
}
state[0] = R0;
state[1] = R1;
state[2] = R2;
state[3] = R3;
state[4] = R4;
position = 0;
}
/*
* WiderWake Key Schedule
*/
void WiderWake_41_BE::key_schedule(const byte key[], u32bit)
{
for(size_t i = 0; i != 4; ++i)
t_key[i] = load_be<u32bit>(key, i);
static const u32bit MAGIC[8] = {
0x726A8F3B, 0xE69A3B5C, 0xD3C71FE5, 0xAB3C73D2,
0x4D3A8EB3, 0x0396D6E8, 0x3D4C2F7A, 0x9EE27CF3 };
for(size_t i = 0; i != 4; ++i)
T[i] = t_key[i];
for(size_t i = 4; i != 256; ++i)
{
u32bit X = T[i-1] + T[i-4];
T[i] = (X >> 3) ^ MAGIC[X % 8];
}
for(size_t i = 0; i != 23; ++i)
T[i] += T[i+89];
u32bit X = T[33];
u32bit Z = (T[59] | 0x01000001) & 0xFF7FFFFF;
for(size_t i = 0; i != 256; ++i)
{
X = (X & 0xFF7FFFFF) + Z;
T[i] = (T[i] & 0x00FFFFFF) ^ X;
}
X = (T[X & 0xFF] ^ X) & 0xFF;
Z = T[0];
T[0] = T[X];
for(size_t i = 1; i != 256; ++i)
{
T[X] = T[i];
X = (T[i ^ X] ^ X) & 0xFF;
T[i] = T[X];
}
T[X] = Z;
position = 0;
const byte ZEROS[8] = { 0 };
set_iv(ZEROS, sizeof(ZEROS));
}
/*
* Resynchronization
*/
void WiderWake_41_BE::set_iv(const byte iv[], size_t length)
{
if(!valid_iv_length(length))
throw Invalid_IV_Length(name(), length);
for(size_t i = 0; i != 4; ++i)
state[i] = t_key[i];
state[4] = load_be<u32bit>(iv, 0);
state[0] ^= state[4];
state[2] ^= load_be<u32bit>(iv, 1);
generate(8*4);
generate(buffer.size());
}
/*
* Clear memory of sensitive data
*/
void WiderWake_41_BE::clear()
{
position = 0;
zeroise(t_key);
zeroise(state);
zeroise(T);
zeroise(buffer);
}
}
|
