File: 3way.cpp

package info (click to toggle)
libcrypto%2B%2B 5.6.1-6%2Bdeb7u2
  • links: PTS
  • area: main
  • in suites: wheezy
  • size: 5,572 kB
  • sloc: cpp: 55,888; asm: 3,521; makefile: 402
file content (139 lines) | stat: -rw-r--r-- 3,326 bytes parent folder | download | duplicates (6)
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
// 3way.cpp - modifed by Wei Dai from Joan Daemen's 3way.c
// The original code and all modifications are in the public domain.

#include "pch.h"
#include "3way.h"
#include "misc.h"

NAMESPACE_BEGIN(CryptoPP)

void ThreeWay_TestInstantiations()
{
	ThreeWay::Encryption x1;
	ThreeWay::Decryption x2;
}

static const word32 START_E = 0x0b0b; // round constant of first encryption round
static const word32 START_D = 0xb1b1; // round constant of first decryption round
static const word32 RC_MODULUS = 0x11011;

static inline word32 reverseBits(word32 a)
{
	a = ((a & 0xAAAAAAAA) >> 1) | ((a & 0x55555555) << 1);
	a = ((a & 0xCCCCCCCC) >> 2) | ((a & 0x33333333) << 2);
	return ((a & 0xF0F0F0F0) >> 4) | ((a & 0x0F0F0F0F) << 4);
}

#define mu(a0, a1, a2)				\
{									\
	a1 = reverseBits(a1);			\
	word32 t = reverseBits(a0);		\
	a0 = reverseBits(a2);			\
	a2 = t;							\
}

#define pi_gamma_pi(a0, a1, a2)		\
{									\
	word32 b0, b2;					\
	b2 = rotlFixed(a2, 1U);				\
	b0 = rotlFixed(a0, 22U);				\
	a0 = rotlFixed(b0 ^ (a1|(~b2)), 1U);	\
	a2 = rotlFixed(b2 ^ (b0|(~a1)), 22U);\
	a1 ^= (b2|(~b0));				\
}

// thanks to Paulo Barreto for this optimized theta()
#define theta(a0, a1, a2)									\
{ 															\
	word32 b0, b1, c; 										\
	c = a0 ^ a1 ^ a2; 										\
	c = rotlFixed(c, 16U) ^ rotlFixed(c, 8U);				\
	b0 = (a0 << 24) ^ (a2 >> 8) ^ (a1 << 8) ^ (a0 >> 24); 	\
	b1 = (a1 << 24) ^ (a0 >> 8) ^ (a2 << 8) ^ (a1 >> 24); 	\
	a0 ^= c ^ b0; 											\
	a1 ^= c ^ b1; 											\
	a2 ^= c ^ (b0 >> 16) ^ (b1 << 16); 						\
}															

#define rho(a0, a1, a2)			\
{								\
	theta(a0, a1, a2);			\
	pi_gamma_pi(a0, a1, a2);	\
}											

void ThreeWay::Base::UncheckedSetKey(const byte *uk, unsigned int length, const NameValuePairs &params)
{
	AssertValidKeyLength(length);

	m_rounds = GetRoundsAndThrowIfInvalid(params, this);

	for (unsigned int i=0; i<3; i++)
		m_k[i] = (word32)uk[4*i+3] | ((word32)uk[4*i+2]<<8) | ((word32)uk[4*i+1]<<16) | ((word32)uk[4*i]<<24);

	if (!IsForwardTransformation())
	{
		theta(m_k[0], m_k[1], m_k[2]);
		mu(m_k[0], m_k[1], m_k[2]);
		m_k[0] = ByteReverse(m_k[0]);
		m_k[1] = ByteReverse(m_k[1]);
		m_k[2] = ByteReverse(m_k[2]);
	}
}

void ThreeWay::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	typedef BlockGetAndPut<word32, BigEndian> Block;

	word32 a0, a1, a2;
	Block::Get(inBlock)(a0)(a1)(a2);

	word32 rc = START_E;

	for(unsigned i=0; i<m_rounds; i++)
	{
		a0 ^= m_k[0] ^ (rc<<16);
		a1 ^= m_k[1];
		a2 ^= m_k[2] ^ rc;
		rho(a0, a1, a2);

		rc <<= 1;
		if (rc&0x10000) rc ^= 0x11011;
	}
	a0 ^= m_k[0] ^ (rc<<16);
	a1 ^= m_k[1];
	a2 ^= m_k[2] ^ rc;
	theta(a0, a1, a2);

	Block::Put(xorBlock, outBlock)(a0)(a1)(a2);
}

void ThreeWay::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	typedef BlockGetAndPut<word32, LittleEndian> Block;

	word32 a0, a1, a2;
	Block::Get(inBlock)(a0)(a1)(a2);

	word32 rc = START_D;

	mu(a0, a1, a2);
	for(unsigned i=0; i<m_rounds; i++)
	{
		a0 ^= m_k[0] ^ (rc<<16);
		a1 ^= m_k[1];
		a2 ^= m_k[2] ^ rc;
		rho(a0, a1, a2);

		rc <<= 1;
		if (rc&0x10000) rc ^= 0x11011;
	}
	a0 ^= m_k[0] ^ (rc<<16);
	a1 ^= m_k[1];
	a2 ^= m_k[2] ^ rc;
	theta(a0, a1, a2);
	mu(a0, a1, a2);

	Block::Put(xorBlock, outBlock)(a0)(a1)(a2);
}

NAMESPACE_END