shark.cpp
// shark.cpp - originally 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"
#if CRYPTOPP_GCC_DIAGNOSTIC_AVAILABLE
# pragma GCC diagnostic ignored "-Wmissing-braces"
#endif
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 &params)
{
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]);
}
#if (CRYPTOPP_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]);
#if (CRYPTOPP_LITTLE_ENDIAN)
m_roundKeys[0] = ByteReverse(m_roundKeys[0]);
m_roundKeys[m_rounds] = ByteReverse(m_roundKeys[m_rounds]);
#endif
}
void SHARK::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
CRYPTOPP_ASSERT(IsAlignedOn(inBlock,GetAlignmentOf<word64>()));
word64 tmp = *(word64 *)(void *)inBlock ^ m_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)]
^ m_roundKeys[1];
for(unsigned int i=2; i<m_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)]
^ m_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)]);
CRYPTOPP_ASSERT(IsAlignedOn(outBlock,GetAlignmentOf<word64>()));
*(word64 *)(void *)outBlock ^= m_roundKeys[m_rounds];
}
void SHARK::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
CRYPTOPP_ASSERT(IsAlignedOn(inBlock,GetAlignmentOf<word64>()));
word64 tmp = *(word64 *)(void *)inBlock ^ m_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)]
^ m_roundKeys[1];
for(unsigned int i=2; i<m_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)]
^ m_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)]);
CRYPTOPP_ASSERT(IsAlignedOn(outBlock,GetAlignmentOf<word64>()));
*(word64 *)(void *)outBlock ^= m_roundKeys[m_rounds];
}
NAMESPACE_END
BlockCipherFinal< ENCRYPTION, Enc >
CipherModeFinalTemplate_ExternalCipher
Definition: modes.h:410
GF256
GF(256) with polynomial basis.
Definition: gf256.h:16
NameValuePairs
Interface for retrieving values given their names.
Definition: cryptlib.h:322
PutBlock
Access a block of memory.
Definition: misc.h:2570
word64
unsigned long long word64
64-bit unsigned datatype
Definition: config_int.h:91
ByteOrder
ByteOrder
Provides the byte ordering.
Definition: cryptlib.h:143
BIG_ENDIAN_ORDER
@ BIG_ENDIAN_ORDER
byte order is big-endian
Definition: cryptlib.h:147
gf256.h
Classes and functions for schemes over GF(256)
misc.h
Utility functions for the Crypto++ library.
ByteReverse
byte ByteReverse(byte value)
Reverses bytes in a 8-bit value.
Definition: misc.h:2021
IsAlignedOn
bool IsAlignedOn(const void *ptr, unsigned int alignment)
Determines whether ptr is aligned to a minimum value.
Definition: misc.h:1226
ConditionalByteReverse
T ConditionalByteReverse(ByteOrder order, T value)
Reverses bytes in a value depending upon endianness.
Definition: misc.h:2187
GetByte
unsigned int GetByte(ByteOrder order, T value, unsigned int index)
Gets a byte from a value.
Definition: misc.h:2009
GetNativeByteOrder
ByteOrder GetNativeByteOrder()
Returns NativeByteOrder as an enumerated ByteOrder value.
Definition: misc.h:1263
modes.h
Classes for block cipher modes of operation.
CryptoPP
Crypto++ library namespace.
Name::IV
const char * IV()
ConstByteArrayParameter, also accepts const byte * for backwards compatibility.
Definition: argnames.h:21
pch.h
Precompiled header file.
swap
void swap(::SecBlock< T, A > &a, ::SecBlock< T, A > &b)
Swap two SecBlocks.
Definition: secblock.h:1289
shark.h
Classes for the SHARK block cipher.
CRYPTOPP_ASSERT
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:68