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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
// seal.cpp - originally written and placed in the public domain by Wei Dai
// updated to SEAL 3.0 by Leonard Janke
#include "pch.h"
#include "seal.h"
#include "cpu.h"
#include "sha.h"
#include "misc.h"
#include "secblock.h"
NAMESPACE_BEGIN(CryptoPP)
#if defined(CRYPTOPP_DEBUG) && !defined(CRYPTOPP_DOXYGEN_PROCESSING)
void SEAL_TestInstantiations()
{
SEAL<>::Encryption x;
}
#endif
struct SEAL_Gamma
{
SEAL_Gamma(const byte *key)
: H(5), Z(5), D(16), lastIndex(0xffffffff)
{
GetUserKey(BIG_ENDIAN_ORDER, H.begin(), 5, key, 20);
memset(D, 0, 64);
}
word32 Apply(word32 i);
SecBlock<word32> H, Z, D;
word32 lastIndex;
};
word32 SEAL_Gamma::Apply(word32 i)
{
word32 shaIndex = i/5;
if (shaIndex != lastIndex)
{
memcpy(Z, H, 20);
D[0] = shaIndex;
SHA1::Transform(Z, D);
lastIndex = shaIndex;
}
return Z[i%5];
}
template <class B>
void SEAL_Policy<B>::CipherSetKey(const NameValuePairs ¶ms, const byte *key, size_t length)
{
CRYPTOPP_UNUSED(length);
m_insideCounter = m_outsideCounter = m_startCount = 0;
unsigned int L = params.GetIntValueWithDefault("NumberOfOutputBitsPerPositionIndex", 32*1024);
m_iterationsPerCount = L / 8192;
SEAL_Gamma gamma(key);
unsigned int i;
for (i=0; i<512; i++)
m_T[i] = gamma.Apply(i);
for (i=0; i<256; i++)
m_S[i] = gamma.Apply(0x1000+i);
m_R.New(4*(L/8192));
for (i=0; i<m_R.size(); i++)
m_R[i] = gamma.Apply(0x2000+i);
}
template <class B>
void SEAL_Policy<B>::CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length)
{
CRYPTOPP_UNUSED(keystreamBuffer), CRYPTOPP_UNUSED(IV), CRYPTOPP_UNUSED(length);
CRYPTOPP_ASSERT(length==4);
m_outsideCounter = IV ? GetWord<word32>(false, BIG_ENDIAN_ORDER, IV) : 0;
m_startCount = m_outsideCounter;
m_insideCounter = 0;
}
template <class B>
void SEAL_Policy<B>::SeekToIteration(lword iterationCount)
{
m_outsideCounter = m_startCount + (unsigned int)(iterationCount / m_iterationsPerCount);
m_insideCounter = (unsigned int)(iterationCount % m_iterationsPerCount);
}
template <class B>
void SEAL_Policy<B>::OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount)
{
word32 a, b, c, d, n1, n2, n3, n4;
unsigned int p, q;
CRYPTOPP_ASSERT(IsAlignedOn(m_T.begin(),GetAlignmentOf<word32>()));
for (size_t iteration = 0; iteration < iterationCount; ++iteration)
{
#define Ttab(x) *(word32 *)(void*)((byte *)m_T.begin()+x)
a = m_outsideCounter ^ m_R[4*m_insideCounter];
b = rotrConstant<8>(m_outsideCounter) ^ m_R[4*m_insideCounter+1];
c = rotrConstant<16>(m_outsideCounter) ^ m_R[4 * m_insideCounter + 2];
d = rotrConstant<24>(m_outsideCounter) ^ m_R[4 * m_insideCounter + 3];
for (unsigned int j=0; j<2; j++)
{
p = a & 0x7fc;
b += Ttab(p);
a = rotrConstant<9>(a);
p = b & 0x7fc;
c += Ttab(p);
b = rotrConstant<9>(b);
p = c & 0x7fc;
d += Ttab(p);
c = rotrConstant<9>(c);
p = d & 0x7fc;
a += Ttab(p);
d = rotrConstant<9>(d);
}
n1 = d, n2 = b, n3 = a, n4 = c;
p = a & 0x7fc;
b += Ttab(p);
a = rotrConstant<9>(a);
p = b & 0x7fc;
c += Ttab(p);
b = rotrConstant<9>(b);
p = c & 0x7fc;
d += Ttab(p);
c = rotrConstant<9>(c);
p = d & 0x7fc;
a += Ttab(p);
d = rotrConstant<9>(d);
// generate 8192 bits
for (unsigned int i=0; i<64; i++)
{
p = a & 0x7fc;
a = rotrConstant<9>(a);
b += Ttab(p);
b ^= a;
q = b & 0x7fc;
b = rotrConstant<9>(b);
c ^= Ttab(q);
c += b;
p = (p+c) & 0x7fc;
c = rotrConstant<9>(c);
d += Ttab(p);
d ^= c;
q = (q+d) & 0x7fc;
d = rotrConstant<9>(d);
a ^= Ttab(q);
a += d;
p = (p+a) & 0x7fc;
b ^= Ttab(p);
a = rotrConstant<9>(a);
q = (q+b) & 0x7fc;
c += Ttab(q);
b = rotrConstant<9>(b);
p = (p+c) & 0x7fc;
d ^= Ttab(p);
c = rotrConstant<9>(c);
q = (q+d) & 0x7fc;
d = rotrConstant<9>(d);
a += Ttab(q);
#define SEAL_OUTPUT(x) \
CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 0, b + m_S[4*i+0]);\
CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 1, c ^ m_S[4*i+1]);\
CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 2, d + m_S[4*i+2]);\
CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 3, a ^ m_S[4*i+3]);
CRYPTOPP_KEYSTREAM_OUTPUT_SWITCH(SEAL_OUTPUT, 4*4);
if (i & 1)
{
a += n3;
b += n4;
c ^= n3;
d ^= n4;
}
else
{
a += n1;
b += n2;
c ^= n1;
d ^= n2;
}
}
if (++m_insideCounter == m_iterationsPerCount)
{
++m_outsideCounter;
m_insideCounter = 0;
}
}
a = b = c = d = n1 = n2 = n3 = n4 = 0;
p = q = 0;
}
template class SEAL_Policy<BigEndian>;
template class SEAL_Policy<LittleEndian>;
NAMESPACE_END
|
