Blame view

Socket/cryptopp/shark.cpp 4.17 KB
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
// shark.cpp - written and placed in the public domain by Wei Dai

#include "pch.h"
#include "shark.h"
#include "misc.h"
#include "modes.h"
#include "gf256.h"

NAMESPACE_BEGIN(CryptoPP)

static word64 SHARKTransform(word64 a)
{
	static const byte iG[8][8] = {
		0xe7, 0x30, 0x90, 0x85, 0xd0, 0x4b, 0x91, 0x41, 
		0x53, 0x95, 0x9b, 0xa5, 0x96, 0xbc, 0xa1, 0x68, 
		0x02, 0x45, 0xf7, 0x65, 0x5c, 0x1f, 0xb6, 0x52, 
		0xa2, 0xca, 0x22, 0x94, 0x44, 0x63, 0x2a, 0xa2, 
		0xfc, 0x67, 0x8e, 0x10, 0x29, 0x75, 0x85, 0x71, 
		0x24, 0x45, 0xa2, 0xcf, 0x2f, 0x22, 0xc1, 0x0e, 
		0xa1, 0xf1, 0x71, 0x40, 0x91, 0x27, 0x18, 0xa5, 
		0x56, 0xf4, 0xaf, 0x32, 0xd2, 0xa4, 0xdc, 0x71, 
	};

	word64 result=0;
	GF256 gf256(0xf5);
	for (unsigned int i=0; i<8; i++)
		for(unsigned int j=0; j<8; j++) 
			result ^= word64(gf256.Multiply(iG[i][j], GF256::Element(a>>(56-8*j)))) << (56-8*i);
	return result;
}

void SHARK::Base::UncheckedSetKey(const byte *key, unsigned int keyLen, const NameValuePairs &params)
{
	AssertValidKeyLength(keyLen);

	m_rounds = GetRoundsAndThrowIfInvalid(params, this);
	m_roundKeys.New(m_rounds+1);

	// concatenate key enought times to fill a
	for (unsigned int i=0; i<(m_rounds+1)*8; i++)
		((byte *)m_roundKeys.begin())[i] = key[i%keyLen];

	SHARK::Encryption e;
	e.InitForKeySetup();
	byte IV[8] = {0,0,0,0,0,0,0,0};
	CFB_Mode_ExternalCipher::Encryption cfb(e, IV);

	cfb.ProcessString((byte *)m_roundKeys.begin(), (m_rounds+1)*8);

	ConditionalByteReverse(BIG_ENDIAN_ORDER, m_roundKeys.begin(), m_roundKeys.begin(), (m_rounds+1)*8);

	m_roundKeys[m_rounds] = SHARKTransform(m_roundKeys[m_rounds]);

	if (!IsForwardTransformation())
	{
		unsigned int i;

		// transform encryption round keys into decryption round keys
		for (i=0; i<m_rounds/2; i++)
			std::swap(m_roundKeys[i], m_roundKeys[m_rounds-i]);

		for (i=1; i<m_rounds; i++)
			m_roundKeys[i] = SHARKTransform(m_roundKeys[i]);
	}

#ifdef IS_LITTLE_ENDIAN
	m_roundKeys[0] = ByteReverse(m_roundKeys[0]);
	m_roundKeys[m_rounds] = ByteReverse(m_roundKeys[m_rounds]);
#endif
}

// construct an SHARK_Enc object with fixed round keys, to be used to initialize actual round keys
void SHARK::Enc::InitForKeySetup()
{
	m_rounds = DEFAULT_ROUNDS;
	m_roundKeys.New(DEFAULT_ROUNDS+1);

	for (unsigned int i=0; i<DEFAULT_ROUNDS; i++)
		m_roundKeys[i] = cbox[0][i];

	m_roundKeys[DEFAULT_ROUNDS] = SHARKTransform(cbox[0][DEFAULT_ROUNDS]);

#ifdef IS_LITTLE_ENDIAN
	m_roundKeys[0] = ByteReverse(m_roundKeys[0]);
	m_roundKeys[m_rounds] = ByteReverse(m_roundKeys[m_rounds]);
#endif
}

typedef word64 ArrayOf256Word64s[256];

template <const byte *sbox, const ArrayOf256Word64s *cbox>
struct SharkProcessAndXorBlock{		// VC60 workaround: problem with template functions
inline SharkProcessAndXorBlock(const word64 *roundKeys, unsigned int rounds, const byte *inBlock, const byte *xorBlock, byte *outBlock)
{
	word64 tmp = *(word64 *)inBlock ^ roundKeys[0];

	ByteOrder order = GetNativeByteOrder();
	tmp = cbox[0][GetByte(order, tmp, 0)] ^ cbox[1][GetByte(order, tmp, 1)] 
		^ cbox[2][GetByte(order, tmp, 2)] ^ cbox[3][GetByte(order, tmp, 3)] 
		^ cbox[4][GetByte(order, tmp, 4)] ^ cbox[5][GetByte(order, tmp, 5)] 
		^ cbox[6][GetByte(order, tmp, 6)] ^ cbox[7][GetByte(order, tmp, 7)]
		^ roundKeys[1];

	for(unsigned int i=2; i<rounds; i++) 
	{
		tmp = cbox[0][GETBYTE(tmp, 7)] ^ cbox[1][GETBYTE(tmp, 6)] 
			^ cbox[2][GETBYTE(tmp, 5)] ^ cbox[3][GETBYTE(tmp, 4)] 
			^ cbox[4][GETBYTE(tmp, 3)] ^ cbox[5][GETBYTE(tmp, 2)] 
			^ cbox[6][GETBYTE(tmp, 1)] ^ cbox[7][GETBYTE(tmp, 0)]
			^ roundKeys[i];
	}

	PutBlock<byte, BigEndian>(xorBlock, outBlock)
		(sbox[GETBYTE(tmp, 7)])
		(sbox[GETBYTE(tmp, 6)])
		(sbox[GETBYTE(tmp, 5)])
		(sbox[GETBYTE(tmp, 4)])
		(sbox[GETBYTE(tmp, 3)])
		(sbox[GETBYTE(tmp, 2)])
		(sbox[GETBYTE(tmp, 1)])
		(sbox[GETBYTE(tmp, 0)]);

	*(word64 *)outBlock ^= roundKeys[rounds];
}};

void SHARK::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	SharkProcessAndXorBlock<sbox, cbox>(m_roundKeys, m_rounds, inBlock, xorBlock, outBlock);
}

void SHARK::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	SharkProcessAndXorBlock<sbox, cbox>(m_roundKeys, m_rounds, inBlock, xorBlock, outBlock);
}

NAMESPACE_END