simeck.cpp
// simeck.cpp - written and placed in the public domain by Gangqiang Yang and Jeffrey Walton.
// Based on "The Simeck Family of Lightweight Block Ciphers" by Gangqiang Yang,
// Bo Zhu, Valentin Suder, Mark D. Aagaard, and Guang Gong
#include "pch.h"
#include "config.h"
#include "simeck.h"
#include "misc.h"
#include "cpu.h"
ANONYMOUS_NAMESPACE_BEGIN
using CryptoPP::rotlConstant;
using CryptoPP::rotrConstant;
/// \brief SIMECK encryption round
/// \tparam T word type
/// \param key the key for the round or iteration
/// \param left the first value
/// \param right the second value
/// \details SIMECK_Encryption serves as the key schedule, encryption and
/// decryption functions.
template <class T>
inline void SIMECK_Encryption(const T key, T& left, T& right)
{
const T temp = left;
left = (left & rotlConstant<5>(left)) ^ rotlConstant<1>(left) ^ right ^ key;
right = temp;
}
ANONYMOUS_NAMESPACE_END
NAMESPACE_BEGIN(CryptoPP)
std::string SIMECK32::Base::AlgorithmProvider() const
{
return "C++";
}
void SIMECK32::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)
{
CRYPTOPP_UNUSED(params);
CRYPTOPP_UNUSED(keyLength);
GetBlock<word16, BigEndian> kblock(userKey);
kblock(m_t[3])(m_t[2])(m_t[1])(m_t[0]);
word16 constant = 0xFFFC;
word32 sequence = 0x9A42BB1F;
for (unsigned int i = 0; i < ROUNDS; ++i)
{
m_rk[i] = m_t[0];
constant &= 0xFFFC;
constant |= sequence & 1;
sequence >>= 1;
SIMECK_Encryption(static_cast<word16>(constant), m_t[1], m_t[0]);
// rotate the LFSR of m_t
m_t[4] = m_t[1];
m_t[1] = m_t[2];
m_t[2] = m_t[3];
m_t[3] = m_t[4];
}
}
void SIMECK32::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Do not cast the buffer. It will SIGBUS on some ARM and SPARC.
GetBlock<word16, BigEndian> iblock(inBlock);
iblock(m_t[1])(m_t[0]);
for (int idx = 0; idx < ROUNDS; ++idx)
SIMECK_Encryption(m_rk[idx], m_t[1], m_t[0]);
PutBlock<word16, BigEndian> oblock(xorBlock, outBlock);
oblock(m_t[1])(m_t[0]);
}
void SIMECK32::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Do not cast the buffer. It will SIGBUS on some ARM and SPARC.
GetBlock<word16, BigEndian> iblock(inBlock);
iblock(m_t[0])(m_t[1]);
for (int idx = ROUNDS - 1; idx >= 0; --idx)
SIMECK_Encryption(m_rk[idx], m_t[1], m_t[0]);
PutBlock<word16, BigEndian> oblock(xorBlock, outBlock);
oblock(m_t[0])(m_t[1]);
}
std::string SIMECK64::Base::AlgorithmProvider() const
{
return "C++";
}
void SIMECK64::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)
{
CRYPTOPP_UNUSED(params);
CRYPTOPP_UNUSED(keyLength);
GetBlock<word32, BigEndian> kblock(userKey);
kblock(m_t[3])(m_t[2])(m_t[1])(m_t[0]);
word64 constant = W64LIT(0xFFFFFFFC);
word64 sequence = W64LIT(0x938BCA3083F);
for (unsigned int i = 0; i < ROUNDS; ++i)
{
m_rk[i] = m_t[0];
constant &= W64LIT(0xFFFFFFFC);
constant |= sequence & 1;
sequence >>= 1;
SIMECK_Encryption(static_cast<word32>(constant), m_t[1], m_t[0]);
// rotate the LFSR of m_t
m_t[4] = m_t[1];
m_t[1] = m_t[2];
m_t[2] = m_t[3];
m_t[3] = m_t[4];
}
}
void SIMECK64::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Do not cast the buffer. It will SIGBUS on some ARM and SPARC.
GetBlock<word32, BigEndian> iblock(inBlock);
iblock(m_t[1])(m_t[0]);
for (int idx = 0; idx < ROUNDS; ++idx)
SIMECK_Encryption(m_rk[idx], m_t[1], m_t[0]);
PutBlock<word32, BigEndian> oblock(xorBlock, outBlock);
oblock(m_t[1])(m_t[0]);
}
void SIMECK64::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Do not cast the buffer. It will SIGBUS on some ARM and SPARC.
GetBlock<word32, BigEndian> iblock(inBlock);
iblock(m_t[0])(m_t[1]);
for (int idx = ROUNDS - 1; idx >= 0; --idx)
SIMECK_Encryption(m_rk[idx], m_t[1], m_t[0]);
PutBlock<word32, BigEndian> oblock(xorBlock, outBlock);
oblock(m_t[0])(m_t[1]);
}
NAMESPACE_END
FixedRounds< 32 >::ROUNDS
static const int ROUNDS
Definition seckey.h:56
config.h
Library configuration file.
W64LIT
#define W64LIT(x)
Declare an unsigned word64.
Definition config_int.h:129
word32
unsigned int word32
32-bit unsigned datatype
Definition config_int.h:72
word16
unsigned short word16
16-bit unsigned datatype
Definition config_int.h:69
word64
unsigned long long word64
64-bit unsigned datatype
Definition config_int.h:101
cpu.h
Functions for CPU features and intrinsics.
misc.h
Utility functions for the Crypto++ library.
rotlConstant
T rotlConstant(T x)
Performs a left rotate.
Definition misc.h:1757
CryptoPP
Crypto++ library namespace.
pch.h
Precompiled header file.
simeck.h
Classes for the SIMECK block cipher.