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// 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(CipherDir dir, const byte *uk, unsigned int length, unsigned int r) 
{ 
	AssertValidKeyLength(length); 
	AssertValidRounds(r); 
 
	m_rounds = r; 
 
	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 (dir == DECRYPTION) 
	{ 
		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 Block; 
 
	word32 a0, a1, a2; 
	Block::Get(inBlock)(a0)(a1)(a2); 
 
	word32 rc = START_E; 
 
	for(unsigned i=0; i Block; 
 
	word32 a0, a1, a2; 
	Block::Get(inBlock)(a0)(a1)(a2); 
 
	word32 rc = START_D; 
 
	mu(a0, a1, a2); 
	for(unsigned i=0; i