ext-cryptopp/speck.cpp

323 lines
9.3 KiB
C++

// speck.h - written and placed in the public domain by Jeffrey Walton
#include "pch.h"
#include "config.h"
#include "speck.h"
#include "misc.h"
ANONYMOUS_NAMESPACE_BEGIN
using CryptoPP::word32;
using CryptoPP::word64;
using CryptoPP::rotlFixed;
using CryptoPP::rotrFixed;
//! \brief Forward round transformation
//! \tparam W word type
//! \details TF83() is the forward round transformation using a=8 and b=3 rotations.
//! The initial test implementation provided template parameters, but they were
//! removed because SPECK32 using a=7 and b=2 was not on the road map. The
//! additional template parameters also made calling SPECK_Encrypt and SPECK_Decrypt
//! kind of messy.
template <class W>
inline void TF83(W& x, W& y, const W& k)
{
x = rotrFixed(x, 8);
x += y; x ^= k;
y = rotlFixed(y, 3);
y ^= x;
}
//! \brief Reverse round transformation
//! \tparam W word type
//! \details TR83() is the reverse round transformation using a=8 and b=3 rotations.
//! The initial test implementation provided template parameters, but they were
//! removed because SPECK32 using a=7 and b=2 was not on the road map. The
//! additional template parameters also made calling SPECK_Encrypt and SPECK_Decrypt
//! kind of messy.
template <class W>
inline void TR83(W& x, W& y, const W& k)
{
y^=x;
y=rotrFixed(y,3);
x^=k; x-=y;
x=rotlFixed(x,8);
}
//! \brief Forward transformation
//! \tparam W word type
//! \tparam R number of rounds
//! \param c output array
//! \param p input array
//! \param k subkey array
template <class W, unsigned int R>
inline void SPECK_Encrypt(W c[2], const W p[2], const W k[R])
{
c[0]=p[0]; c[1]=p[1];
// Don't unroll this loop. Things slow down.
for (size_t i=0; static_cast<int>(i)<R; ++i)
TF83(c[0], c[1], k[i]);
}
//! \brief Reverse transformation
//! \tparam W word type
//! \tparam R number of rounds
//! \param p output array
//! \param c input array
//! \param k subkey array
template <class W, unsigned int R>
inline void SPECK_Decrypt(W p[2], const W c[2], const W k[R])
{
p[0]=c[0]; p[1]=c[1];
// Don't unroll this loop. Things slow down.
for (size_t i=R-1; static_cast<int>(i)>=0; --i)
TR83(p[0], p[1], k[i]);
}
//! \brief Subkey generation function
//! \details Used when the user key consists of 2 words
//! \tparam W word type
//! \tparam R number of rounds
//! \param key empty subkey array
//! \param k user key array
template <class W, unsigned int R>
inline void SPECK_ExpandKey_2W(W key[R], const W k[2])
{
CRYPTOPP_ASSERT(R==32);
W i=0, B=k[0], A=k[1];
while(i<R-1)
{
key[i]=A; TF83(B, A, i);
i++;
}
key[R-1]=A;
}
//! \brief Subkey generation function
//! \details Used when the user key consists of 3 words
//! \tparam W word type
//! \tparam R number of rounds
//! \param key empty subkey array
//! \param k user key array
template <class W, unsigned int R>
inline void SPECK_ExpandKey_3W(W key[R], const W k[3])
{
CRYPTOPP_ASSERT(R==33 || R==26);
W i=0, C=k[0], B=k[1], A=k[2];
unsigned int blocks = R/2;
while(blocks--)
{
key[i+0]=A; TF83(B, A, i+0);
key[i+1]=A; TF83(C, A, i+1);
i+=2;
}
// The constexpr residue should allow the optimizer to remove unneeded statements
if(R%2 == 1)
{
key[R-1]=A;
}
}
//! \brief Subkey generation function
//! \details Used when the user key consists of 4 words
//! \tparam W word type
//! \tparam R number of rounds
//! \param key empty subkey array
//! \param k user key array
template <class W, unsigned int R>
inline void SPECK_ExpandKey_4W(W key[R], const W k[4])
{
CRYPTOPP_ASSERT(R==34 || R==27);
W i=0, D=k[0], C=k[1], B=k[2], A=k[3];
unsigned int blocks = R/3;
while(blocks--)
{
key[i+0]=A; TF83(B, A, i+0);
key[i+1]=A; TF83(C, A, i+1);
key[i+2]=A; TF83(D, A, i+2);
i+=3;
}
// The constexpr residue should allow the optimizer to remove unneeded statements
if(R%3 == 1)
{
key[R-1]=A;
}
else if(R%3 == 2)
{
key[R-2]=A; TF83(B, A, W(R-2));
key[R-1]=A;
}
}
ANONYMOUS_NAMESPACE_END
///////////////////////////////////////////////////////////
NAMESPACE_BEGIN(CryptoPP)
void SPECK64::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)
{
CRYPTOPP_ASSERT(keyLength == 12 || keyLength == 16);
CRYPTOPP_UNUSED(params);
// Building the key schedule table requires {3,4} words workspace.
// Encrypting and decrypting requires 4 words workspace.
m_kwords = keyLength/sizeof(word32);
m_wspace.New(STDMAX(m_kwords,4U));
GetUserKey(BIG_ENDIAN_ORDER, m_wspace.begin(), m_kwords, userKey, keyLength);
switch (m_kwords)
{
case 3:
m_rkey.New(26);
SPECK_ExpandKey_3W<word32, 26>(m_rkey, m_wspace);
break;
case 4:
m_rkey.New(27);
SPECK_ExpandKey_4W<word32, 27>(m_rkey, m_wspace);
break;
default:
CRYPTOPP_ASSERT(0);;
}
}
void SPECK64::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef GetBlock<word32, BigEndian, false> InBlock;
InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);
switch (m_kwords)
{
case 3:
SPECK_Encrypt<word32, 26>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 4:
SPECK_Encrypt<word32, 27>(m_wspace+2, m_wspace+0, m_rkey);
break;
default:
CRYPTOPP_ASSERT(0);;
}
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef PutBlock<word32, BigEndian, false> OutBlock;
OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);
}
void SPECK64::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef GetBlock<word32, BigEndian, false> InBlock;
InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);
switch (m_kwords)
{
case 3:
SPECK_Decrypt<word32, 26>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 4:
SPECK_Decrypt<word32, 27>(m_wspace+2, m_wspace+0, m_rkey);
break;
default:
CRYPTOPP_ASSERT(0);;
}
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef PutBlock<word32, BigEndian, false> OutBlock;
OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);
}
///////////////////////////////////////////////////////////
void SPECK128::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)
{
CRYPTOPP_ASSERT(keyLength == 16 || keyLength == 24 || keyLength == 32);
CRYPTOPP_UNUSED(params);
// Building the key schedule table requires {2,3,4} words workspace.
// Encrypting and decrypting requires 4 words workspace.
m_kwords = keyLength/sizeof(word64);
m_wspace.New(STDMAX(m_kwords,4U));
GetUserKey(BIG_ENDIAN_ORDER, m_wspace.begin(), m_kwords, userKey, keyLength);
switch (m_kwords)
{
case 2:
m_rkey.New(32);
SPECK_ExpandKey_2W<word64, 32>(m_rkey, m_wspace);
break;
case 3:
m_rkey.New(33);
SPECK_ExpandKey_3W<word64, 33>(m_rkey, m_wspace);
break;
case 4:
m_rkey.New(34);
SPECK_ExpandKey_4W<word64, 34>(m_rkey, m_wspace);
break;
default:
CRYPTOPP_ASSERT(0);;
}
}
void SPECK128::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef GetBlock<word64, BigEndian, false> InBlock;
InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);
switch (m_kwords)
{
case 2:
SPECK_Encrypt<word64, 32>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 3:
SPECK_Encrypt<word64, 33>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 4:
SPECK_Encrypt<word64, 34>(m_wspace+2, m_wspace+0, m_rkey);
break;
default:
CRYPTOPP_ASSERT(0);;
}
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef PutBlock<word64, BigEndian, false> OutBlock;
OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);
}
void SPECK128::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef GetBlock<word64, BigEndian, false> InBlock;
InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);
switch (m_kwords)
{
case 2:
SPECK_Decrypt<word64, 32>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 3:
SPECK_Decrypt<word64, 33>(m_wspace+2, m_wspace+0, m_rkey);
break;
case 4:
SPECK_Decrypt<word64, 34>(m_wspace+2, m_wspace+0, m_rkey);
break;
default:
CRYPTOPP_ASSERT(0);;
}
// Reverse bytes on LittleEndian; align pointer on BigEndian
typedef PutBlock<word64, BigEndian, false> OutBlock;
OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);
}
NAMESPACE_END