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
|
// tea.cpp - modified by Wei Dai from code in the original paper
#include "pch.h"
#include "tea.h"
#include "misc.h"
NAMESPACE_BEGIN(CryptoPP)
static const word32 DELTA = 0x9e3779b9;
typedef BlockGetAndPut<word32, BigEndian> Block;
void TEA::Base::UncheckedSetKey(const byte *userKey, unsigned int length, const NameValuePairs ¶ms)
{
AssertValidKeyLength(length);
GetUserKey(BIG_ENDIAN_ORDER, m_k.begin(), 4, userKey, KEYLENGTH);
m_limit = GetRoundsAndThrowIfInvalid(params, this) * DELTA;
}
void TEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word32 y, z;
Block::Get(inBlock)(y)(z);
word32 sum = 0;
while (sum != m_limit)
{
sum += DELTA;
y += (z << 4) + m_k[0] ^ z + sum ^ (z >> 5) + m_k[1];
z += (y << 4) + m_k[2] ^ y + sum ^ (y >> 5) + m_k[3];
}
Block::Put(xorBlock, outBlock)(y)(z);
}
void TEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word32 y, z;
Block::Get(inBlock)(y)(z);
word32 sum = m_limit;
while (sum != 0)
{
z -= (y << 4) + m_k[2] ^ y + sum ^ (y >> 5) + m_k[3];
y -= (z << 4) + m_k[0] ^ z + sum ^ (z >> 5) + m_k[1];
sum -= DELTA;
}
Block::Put(xorBlock, outBlock)(y)(z);
}
void XTEA::Base::UncheckedSetKey(const byte *userKey, unsigned int length, const NameValuePairs ¶ms)
{
AssertValidKeyLength(length);
GetUserKey(BIG_ENDIAN_ORDER, m_k.begin(), 4, userKey, KEYLENGTH);
m_limit = GetRoundsAndThrowIfInvalid(params, this) * DELTA;
}
void XTEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word32 y, z;
Block::Get(inBlock)(y)(z);
#ifdef __SUNPRO_CC
// workaround needed on Sun Studio 12u1 Sun C++ 5.10 SunOS_i386 128229-02 2009/09/21
size_t sum = 0;
while ((sum&0xffffffff) != m_limit)
#else
word32 sum = 0;
while (sum != m_limit)
#endif
{
y += (z<<4 ^ z>>5) + z ^ sum + m_k[sum&3];
sum += DELTA;
z += (y<<4 ^ y>>5) + y ^ sum + m_k[sum>>11 & 3];
}
Block::Put(xorBlock, outBlock)(y)(z);
}
void XTEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
word32 y, z;
Block::Get(inBlock)(y)(z);
#ifdef __SUNPRO_CC
// workaround needed on Sun Studio 12u1 Sun C++ 5.10 SunOS_i386 128229-02 2009/09/21
size_t sum = m_limit;
while ((sum&0xffffffff) != 0)
#else
word32 sum = m_limit;
while (sum != 0)
#endif
{
z -= (y<<4 ^ y>>5) + y ^ sum + m_k[sum>>11 & 3];
sum -= DELTA;
y -= (z<<4 ^ z>>5) + z ^ sum + m_k[sum&3];
}
Block::Put(xorBlock, outBlock)(y)(z);
}
#define MX (z>>5^y<<2)+(y>>3^z<<4)^(sum^y)+(m_k[p&3^e]^z)
void BTEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
unsigned int n = m_blockSize / 4;
word32 *v = (word32*)outBlock;
ConditionalByteReverse(BIG_ENDIAN_ORDER, v, (const word32*)inBlock, m_blockSize);
word32 y = v[0], z = v[n-1], e;
word32 p, q = 6+52/n;
word32 sum = 0;
while (q-- > 0)
{
sum += DELTA;
e = sum>>2 & 3;
for (p = 0; p < n-1; p++)
{
y = v[p+1];
z = v[p] += MX;
}
y = v[0];
z = v[n-1] += MX;
}
ConditionalByteReverse(BIG_ENDIAN_ORDER, v, v, m_blockSize);
}
void BTEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
unsigned int n = m_blockSize / 4;
word32 *v = (word32*)outBlock;
ConditionalByteReverse(BIG_ENDIAN_ORDER, v, (const word32*)inBlock, m_blockSize);
word32 y = v[0], z = v[n-1], e;
word32 p, q = 6+52/n;
word32 sum = q * DELTA;
while (sum != 0)
{
e = sum>>2 & 3;
for (p = n-1; p > 0; p--)
{
z = v[p-1];
y = v[p] -= MX;
}
z = v[n-1];
y = v[0] -= MX;
sum -= DELTA;
}
ConditionalByteReverse(BIG_ENDIAN_ORDER, v, v, m_blockSize);
}
NAMESPACE_END
|
