seal.h
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// seal.h - written and placed in the public domain by Wei Dai
//! \file seal.h
//! \brief Classes for SEAL stream cipher
#ifndef CRYPTOPP_SEAL_H
#define CRYPTOPP_SEAL_H
#include "strciphr.h"
#include "secblock.h"
NAMESPACE_BEGIN(CryptoPP)
//! \class SEAL_Info
//! \brief SEAL stream cipher information
//! \tparam B Endianess of the stream cipher
template <class B = BigEndian>
struct SEAL_Info : public FixedKeyLength<20, SimpleKeyingInterface::INTERNALLY_GENERATED_IV, 4>
{
CRYPTOPP_CONSTEXPR static const char *StaticAlgorithmName() {return B::ToEnum() == LITTLE_ENDIAN_ORDER ? "SEAL-3.0-LE" : "SEAL-3.0-BE";}
};
//! \class SEAL_Policy
//! \brief SEAL stream cipher operation
//! \tparam B Endianess of the stream cipher
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;
};
//! \class SEAL
//! \brief SEAL stream cipher
//! \tparam B Endianess of the stream cipher
//! \sa <a href="http://www.weidai.com/scan-mirror/cs.html#SEAL-3.0-BE">SEAL</a>
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
SEAL_Policy
SEAL stream cipher operation.
Definition: seal.h:27
FixedKeyLength
Inherited by keyed algorithms with fixed key length.
Definition: seckey.h:128
AdditiveCipherConcretePolicy
Base class for additive stream ciphers.
Definition: strciphr.h:188
SecBlock< word32 >
LITTLE_ENDIAN_ORDER
byte order is little-endian
Definition: cryptlib.h:125
secblock.h
Classes and functions for secure memory allocations.
SEAL_Info
SEAL stream cipher information.
Definition: seal.h:18
FixedSizeSecBlock< word32, 512 >
SEAL
SEAL stream cipher.
Definition: seal.h:50
Name::IV
const char * IV()
ConstByteArrayParameter, also accepts const byte * for backwards compatibility.
Definition: argnames.h:21
strciphr.h
Classes for implementing stream ciphers.
SymmetricCipherDocumentation
Provides Encryption and Decryption typedefs used by derived classes to implement a symmetric cipher...
Definition: seckey.h:439
KeystreamOperation
KeystreamOperation
Keystream operation flags.
Definition: strciphr.h:92
CryptoPP
Crypto++ library namespace.
SymmetricCipherFinal
SymmetricCipher implementation.
Definition: strciphr.h:582
AdditiveCipherTemplate
Base class for additive stream ciphers with SymmetricCipher interface.
Definition: strciphr.h:269
NameValuePairs
Interface for retrieving values given their names.
Definition: cryptlib.h:277