diff options
Diffstat (limited to 'CryptoPP/shark.cpp')
| -rw-r--r-- | CryptoPP/shark.cpp | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/CryptoPP/shark.cpp b/CryptoPP/shark.cpp new file mode 100644 index 000000000..361147e23 --- /dev/null +++ b/CryptoPP/shark.cpp @@ -0,0 +1,136 @@ +// 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 ¶ms) +{ + 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 |