emsa2.h
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// emsa2.h - originally written and placed in the public domain by Wei Dai
/// \file emsa2.h
/// \brief Classes and functions for various padding schemes used in public key algorithms
#ifndef CRYPTOPP_EMSA2_H
#define CRYPTOPP_EMSA2_H
#include "cryptlib.h"
#include "pubkey.h"
#include "hashfwd.h"
#include "misc.h"
#ifdef CRYPTOPP_IS_DLL
# include "sha.h"
#endif
NAMESPACE_BEGIN(CryptoPP)
/// \brief EMSA2 hash identifier
/// \tparam H HashTransformation derived class
/// \since Crypto++ 5.0
template <class H> class EMSA2HashId
{
public:
static const byte id;
};
/// \brief EMSA2 padding method
/// \tparam BASE Message encoding method
/// \since Crypto++ 5.0
template <class BASE>
class EMSA2HashIdLookup : public BASE
{
public:
struct HashIdentifierLookup
{
template <class H> struct HashIdentifierLookup2
{
static HashIdentifier Lookup()
{
return HashIdentifier(&EMSA2HashId<H>::id, 1);
}
};
};
};
// EMSA2HashId can be instantiated with the following classes.
// SHA1, SHA224, SHA256, SHA384, SHA512, RIPEMD128, RIPEMD160, Whirlpool
#ifdef CRYPTOPP_IS_DLL
CRYPTOPP_DLL_TEMPLATE_CLASS EMSA2HashId<SHA1>;
CRYPTOPP_DLL_TEMPLATE_CLASS EMSA2HashId<SHA224>;
CRYPTOPP_DLL_TEMPLATE_CLASS EMSA2HashId<SHA256>;
CRYPTOPP_DLL_TEMPLATE_CLASS EMSA2HashId<SHA384>;
CRYPTOPP_DLL_TEMPLATE_CLASS EMSA2HashId<SHA512>;
#endif
// https://github.com/weidai11/cryptopp/issues/300 and
// https://github.com/weidai11/cryptopp/issues/533
#if defined(__clang__)
template<> const byte EMSA2HashId<SHA1>::id;
template<> const byte EMSA2HashId<SHA224>::id;
template<> const byte EMSA2HashId<SHA256>::id;
template<> const byte EMSA2HashId<SHA384>::id;
template<> const byte EMSA2HashId<SHA512>::id;
#endif
/// \brief EMSA2 padding method
/// \since Crypto++ 5.0
class CRYPTOPP_DLL EMSA2Pad : public EMSA2HashIdLookup<PK_DeterministicSignatureMessageEncodingMethod>
{
public:
CRYPTOPP_STATIC_CONSTEXPR const char* CRYPTOPP_API StaticAlgorithmName() {return "EMSA2";}
size_t MinRepresentativeBitLength(size_t hashIdentifierLength, size_t digestLength) const
{CRYPTOPP_UNUSED(hashIdentifierLength); return 8*digestLength + 31;}
void ComputeMessageRepresentative(RandomNumberGenerator &rng,
const byte *recoverableMessage, size_t recoverableMessageLength,
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const;
};
// EMSA2, for use with RWSS and RSA_ISO
// Only the following hash functions are supported by this signature standard:
// \dontinclude emsa2.h
// \skip EMSA2HashId can be instantiated
// \until end of list
/// \brief EMSA2/P1363 padding method
/// \details Use with RWSS and RSA_ISO
/// \since Crypto++ 5.0
struct P1363_EMSA2 : public SignatureStandard
{
typedef EMSA2Pad SignatureMessageEncodingMethod;
};
NAMESPACE_END
#endif
EMSA2HashId
EMSA2 hash identifier.
Definition emsa2.h:24
EMSA2HashIdLookup
EMSA2 padding method.
Definition emsa2.h:34
EMSA2Pad
EMSA2 padding method.
Definition emsa2.h:72
HashTransformation
Interface for hash functions and data processing part of MACs.
Definition cryptlib.h:1118
RandomNumberGenerator
Interface for random number generators.
Definition cryptlib.h:1440
CRYPTOPP_API
#define CRYPTOPP_API
Win32 calling convention.
Definition config_dll.h:119
CRYPTOPP_DLL_TEMPLATE_CLASS
#define CRYPTOPP_DLL_TEMPLATE_CLASS
Instantiate templates in a dynamic library.
Definition config_dll.h:72
cryptlib.h
Abstract base classes that provide a uniform interface to this library.
hashfwd.h
Forward declarations for hash functions used in signature encoding methods.
misc.h
Utility functions for the Crypto++ library.
CryptoPP
Crypto++ library namespace.
pubkey.h
This file contains helper classes/functions for implementing public key algorithms.
sha.h
Classes for SHA-1 and SHA-2 family of message digests.
EMSA2HashIdLookup::HashIdentifierLookup::HashIdentifierLookup2
Definition emsa2.h:39
EMSA2HashIdLookup::HashIdentifierLookup
Definition emsa2.h:37
P1363_EMSA2
EMSA2/P1363 padding method.
Definition emsa2.h:95
SignatureStandard
Base class for public key signature standard classes.
Definition pubkey.h:2279