seal.h

Go to the documentation of this file.

// seal.h - originally written and placed in the public domain by Wei Dai
 
 
#ifndef CRYPTOPP_SEAL_H
#define CRYPTOPP_SEAL_H
 
#include "strciphr.h"
#include "secblock.h"
 
NAMESPACE_BEGIN(CryptoPP)
 
 
template <class B = BigEndian>
struct SEAL_Info : public FixedKeyLength<20, SimpleKeyingInterface::INTERNALLY_GENERATED_IV, 4>
{
        CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return B::ToEnum() == LITTLE_ENDIAN_ORDER ? "SEAL-3.0-LE" : "SEAL-3.0-BE";}
};
 
template <class B = BigEndian>
class CRYPTOPP_NO_VTABLE SEAL_Policy : public AdditiveCipherConcretePolicy<word32, 256>, public SEAL_Info<B>
{
protected:
        void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length);
        void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount);
        void CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length);
        bool CipherIsRandomAccess() const {return true;}
        void SeekToIteration(lword iterationCount);
 
private:
        FixedSizeSecBlock<word32, 512> m_T;
        FixedSizeSecBlock<word32, 256> m_S;
        SecBlock<word32> m_R;
 
        word32 m_startCount, m_iterationsPerCount;
        word32 m_outsideCounter, m_insideCounter;
};
 
template <class B = BigEndian>
struct SEAL : public SEAL_Info<B>, public SymmetricCipherDocumentation
{
        typedef SymmetricCipherFinal<ConcretePolicyHolder<SEAL_Policy<B>, AdditiveCipherTemplate<> >, SEAL_Info<B> > Encryption;
        typedef Encryption Decryption;
};
 
NAMESPACE_END
 
#endif