1// 3way.cpp - modifed by Wei Dai from Joan Daemen's 3way.c 2// The original code and all modifications are in the public domain. 3 4#include "pch.h" 5#include "3way.h" 6#include "misc.h" 7 8NAMESPACE_BEGIN(CryptoPP) 9 10void ThreeWay_TestInstantiations() 11{ 12 ThreeWay::Encryption x1; 13 ThreeWay::Decryption x2; 14} 15 16static const word32 START_E = 0x0b0b; // round constant of first encryption round 17static const word32 START_D = 0xb1b1; // round constant of first decryption round 18static const word32 RC_MODULUS = 0x11011; 19 20static inline word32 reverseBits(word32 a) 21{ 22 a = ((a & 0xAAAAAAAA) >> 1) | ((a & 0x55555555) << 1); 23 a = ((a & 0xCCCCCCCC) >> 2) | ((a & 0x33333333) << 2); 24 return ((a & 0xF0F0F0F0) >> 4) | ((a & 0x0F0F0F0F) << 4); 25} 26 27#define mu(a0, a1, a2) \ 28{ \ 29 a1 = reverseBits(a1); \ 30 word32 t = reverseBits(a0); \ 31 a0 = reverseBits(a2); \ 32 a2 = t; \ 33} 34 35#define pi_gamma_pi(a0, a1, a2) \ 36{ \ 37 word32 b0, b2; \ 38 b2 = rotlFixed(a2, 1U); \ 39 b0 = rotlFixed(a0, 22U); \ 40 a0 = rotlFixed(b0 ^ (a1|(~b2)), 1U); \ 41 a2 = rotlFixed(b2 ^ (b0|(~a1)), 22U);\ 42 a1 ^= (b2|(~b0)); \ 43} 44 45// thanks to Paulo Barreto for this optimized theta() 46#define theta(a0, a1, a2) \ 47{ \ 48 word32 b0, b1, c; \ 49 c = a0 ^ a1 ^ a2; \ 50 c = rotlFixed(c, 16U) ^ rotlFixed(c, 8U); \ 51 b0 = (a0 << 24) ^ (a2 >> 8) ^ (a1 << 8) ^ (a0 >> 24); \ 52 b1 = (a1 << 24) ^ (a0 >> 8) ^ (a2 << 8) ^ (a1 >> 24); \ 53 a0 ^= c ^ b0; \ 54 a1 ^= c ^ b1; \ 55 a2 ^= c ^ (b0 >> 16) ^ (b1 << 16); \ 56} 57 58#define rho(a0, a1, a2) \ 59{ \ 60 theta(a0, a1, a2); \ 61 pi_gamma_pi(a0, a1, a2); \ 62} 63 64void ThreeWay::Base::UncheckedSetKey(const byte *uk, unsigned int length, const NameValuePairs ¶ms) 65{ 66 AssertValidKeyLength(length); 67 68 m_rounds = GetRoundsAndThrowIfInvalid(params, this); 69 70 for (unsigned int i=0; i<3; i++) 71 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); 72 73 if (!IsForwardTransformation()) 74 { 75 theta(m_k[0], m_k[1], m_k[2]); 76 mu(m_k[0], m_k[1], m_k[2]); 77 m_k[0] = ByteReverse(m_k[0]); 78 m_k[1] = ByteReverse(m_k[1]); 79 m_k[2] = ByteReverse(m_k[2]); 80 } 81} 82 83void ThreeWay::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const 84{ 85 typedef BlockGetAndPut<word32, BigEndian> Block; 86 87 word32 a0, a1, a2; 88 Block::Get(inBlock)(a0)(a1)(a2); 89 90 word32 rc = START_E; 91 92 for(unsigned i=0; i<m_rounds; i++) 93 { 94 a0 ^= m_k[0] ^ (rc<<16); 95 a1 ^= m_k[1]; 96 a2 ^= m_k[2] ^ rc; 97 rho(a0, a1, a2); 98 99 rc <<= 1; 100 if (rc&0x10000) rc ^= 0x11011; 101 } 102 a0 ^= m_k[0] ^ (rc<<16); 103 a1 ^= m_k[1]; 104 a2 ^= m_k[2] ^ rc; 105 theta(a0, a1, a2); 106 107 Block::Put(xorBlock, outBlock)(a0)(a1)(a2); 108} 109 110void ThreeWay::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const 111{ 112 typedef BlockGetAndPut<word32, LittleEndian> Block; 113 114 word32 a0, a1, a2; 115 Block::Get(inBlock)(a0)(a1)(a2); 116 117 word32 rc = START_D; 118 119 mu(a0, a1, a2); 120 for(unsigned i=0; i<m_rounds; i++) 121 { 122 a0 ^= m_k[0] ^ (rc<<16); 123 a1 ^= m_k[1]; 124 a2 ^= m_k[2] ^ rc; 125 rho(a0, a1, a2); 126 127 rc <<= 1; 128 if (rc&0x10000) rc ^= 0x11011; 129 } 130 a0 ^= m_k[0] ^ (rc<<16); 131 a1 ^= m_k[1]; 132 a2 ^= m_k[2] ^ rc; 133 theta(a0, a1, a2); 134 mu(a0, a1, a2); 135 136 Block::Put(xorBlock, outBlock)(a0)(a1)(a2); 137} 138 139NAMESPACE_END 140