00001
00002
00003
00004 #include "pch.h"
00005 #include "3way.h"
00006 #include "misc.h"
00007
00008 NAMESPACE_BEGIN(CryptoPP)
00009
00010 void ThreeWay_TestInstantiations()
00011 {
00012 ThreeWay::Encryption x1;
00013 ThreeWay::Decryption x2;
00014 }
00015
00016 static const word32 START_E = 0x0b0b;
00017 static const word32 START_D = 0xb1b1;
00018 static const word32 RC_MODULUS = 0x11011;
00019
00020 static inline word32 reverseBits(word32 a)
00021 {
00022 a = ((a & 0xAAAAAAAA) >> 1) | ((a & 0x55555555) << 1);
00023 a = ((a & 0xCCCCCCCC) >> 2) | ((a & 0x33333333) << 2);
00024 return ((a & 0xF0F0F0F0) >> 4) | ((a & 0x0F0F0F0F) << 4);
00025 }
00026
00027 #define mu(a0, a1, a2) \
00028 { \
00029 a1 = reverseBits(a1); \
00030 word32 t = reverseBits(a0); \
00031 a0 = reverseBits(a2); \
00032 a2 = t; \
00033 }
00034
00035 #define pi_gamma_pi(a0, a1, a2) \
00036 { \
00037 word32 b0, b2; \
00038 b2 = rotlFixed(a2, 1U); \
00039 b0 = rotlFixed(a0, 22U); \
00040 a0 = rotlFixed(b0 ^ (a1|(~b2)), 1U); \
00041 a2 = rotlFixed(b2 ^ (b0|(~a1)), 22U);\
00042 a1 ^= (b2|(~b0)); \
00043 }
00044
00045
00046 #define theta(a0, a1, a2) \
00047 { \
00048 word32 b0, b1, c; \
00049 c = a0 ^ a1 ^ a2; \
00050 c = rotlFixed(c, 16U) ^ rotlFixed(c, 8U); \
00051 b0 = (a0 << 24) ^ (a2 >> 8) ^ (a1 << 8) ^ (a0 >> 24); \
00052 b1 = (a1 << 24) ^ (a0 >> 8) ^ (a2 << 8) ^ (a1 >> 24); \
00053 a0 ^= c ^ b0; \
00054 a1 ^= c ^ b1; \
00055 a2 ^= c ^ (b0 >> 16) ^ (b1 << 16); \
00056 }
00057
00058 #define rho(a0, a1, a2) \
00059 { \
00060 theta(a0, a1, a2); \
00061 pi_gamma_pi(a0, a1, a2); \
00062 }
00063
00064 void ThreeWay::Base::UncheckedSetKey(CipherDir dir, const byte *uk, unsigned int length, unsigned int r)
00065 {
00066 AssertValidKeyLength(length);
00067 AssertValidRounds(r);
00068
00069 m_rounds = r;
00070
00071 for (unsigned int i=0; i<3; i++)
00072 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);
00073
00074 if (dir == DECRYPTION)
00075 {
00076 theta(m_k[0], m_k[1], m_k[2]);
00077 mu(m_k[0], m_k[1], m_k[2]);
00078 m_k[0] = ByteReverse(m_k[0]);
00079 m_k[1] = ByteReverse(m_k[1]);
00080 m_k[2] = ByteReverse(m_k[2]);
00081 }
00082 }
00083
00084 void ThreeWay::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
00085 {
00086 typedef BlockGetAndPut<word32, BigEndian> Block;
00087
00088 word32 a0, a1, a2;
00089 Block::Get(inBlock)(a0)(a1)(a2);
00090
00091 word32 rc = START_E;
00092
00093 for(unsigned i=0; i<m_rounds; i++)
00094 {
00095 a0 ^= m_k[0] ^ (rc<<16);
00096 a1 ^= m_k[1];
00097 a2 ^= m_k[2] ^ rc;
00098 rho(a0, a1, a2);
00099
00100 rc <<= 1;
00101 if (rc&0x10000) rc ^= 0x11011;
00102 }
00103 a0 ^= m_k[0] ^ (rc<<16);
00104 a1 ^= m_k[1];
00105 a2 ^= m_k[2] ^ rc;
00106 theta(a0, a1, a2);
00107
00108 Block::Put(xorBlock, outBlock)(a0)(a1)(a2);
00109 }
00110
00111 void ThreeWay::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
00112 {
00113 typedef BlockGetAndPut<word32, LittleEndian> Block;
00114
00115 word32 a0, a1, a2;
00116 Block::Get(inBlock)(a0)(a1)(a2);
00117
00118 word32 rc = START_D;
00119
00120 mu(a0, a1, a2);
00121 for(unsigned i=0; i<m_rounds; i++)
00122 {
00123 a0 ^= m_k[0] ^ (rc<<16);
00124 a1 ^= m_k[1];
00125 a2 ^= m_k[2] ^ rc;
00126 rho(a0, a1, a2);
00127
00128 rc <<= 1;
00129 if (rc&0x10000) rc ^= 0x11011;
00130 }
00131 a0 ^= m_k[0] ^ (rc<<16);
00132 a1 ^= m_k[1];
00133 a2 ^= m_k[2] ^ rc;
00134 theta(a0, a1, a2);
00135 mu(a0, a1, a2);
00136
00137 Block::Put(xorBlock, outBlock)(a0)(a1)(a2);
00138 }
00139
00140 NAMESPACE_END