ext-cryptopp/gf2_32.h
2016-10-18 20:21:47 -04:00

74 lines
1.5 KiB
C++

// gf2_32.h - written and placed in the public domain by Wei Dai
//! \file gf2_32.h
//! \brief Classes and functions for schemes over GF(2^32)
#ifndef CRYPTOPP_GF2_32_H
#define CRYPTOPP_GF2_32_H
#include "cryptlib.h"
#include "secblock.h"
#include "misc.h"
NAMESPACE_BEGIN(CryptoPP)
//! \brief GF(2^32) with polynomial basis
class GF2_32
{
public:
typedef word32 Element;
typedef int RandomizationParameter;
GF2_32(word32 modulus=0x0000008D) : m_modulus(modulus) {}
Element RandomElement(RandomNumberGenerator &rng, int ignored = 0) const
{CRYPTOPP_UNUSED(ignored); return rng.GenerateWord32();}
bool Equal(Element a, Element b) const
{return a==b;}
Element Identity() const
{return 0;}
Element Add(Element a, Element b) const
{return a^b;}
Element& Accumulate(Element &a, Element b) const
{return a^=b;}
Element Inverse(Element a) const
{return a;}
Element Subtract(Element a, Element b) const
{return a^b;}
Element& Reduce(Element &a, Element b) const
{return a^=b;}
Element Double(Element a) const
{CRYPTOPP_UNUSED(a); return 0;}
Element MultiplicativeIdentity() const
{return 1;}
Element Multiply(Element a, Element b) const;
Element Square(Element a) const
{return Multiply(a, a);}
bool IsUnit(Element a) const
{return a != 0;}
Element MultiplicativeInverse(Element a) const;
Element Divide(Element a, Element b) const
{return Multiply(a, MultiplicativeInverse(b));}
private:
word32 m_modulus;
};
NAMESPACE_END
#endif