ext-cryptopp/iterhash.h
2005-07-12 04:23:32 +00:00

109 lines
3.6 KiB
C++

#ifndef CRYPTOPP_ITERHASH_H
#define CRYPTOPP_ITERHASH_H
#include "cryptlib.h"
#include "secblock.h"
#include "misc.h"
#include "simple.h"
NAMESPACE_BEGIN(CryptoPP)
//! exception thrown when trying to hash more data than is allowed by a hash function
class CRYPTOPP_DLL HashInputTooLong : public InvalidDataFormat
{
public:
explicit HashInputTooLong(const std::string &alg)
: InvalidDataFormat("IteratedHashBase: input data exceeds maximum allowed by hash function " + alg) {}
};
//! _
template <class T, class BASE>
class CRYPTOPP_NO_VTABLE IteratedHashBase : public BASE
{
public:
typedef T HashWordType;
IteratedHashBase() : m_countLo(0), m_countHi(0) {}
unsigned int BlockSize() const {return (unsigned int)m_data.size() * sizeof(T);}
unsigned int OptimalBlockSize() const {return BlockSize();}
unsigned int OptimalDataAlignment() const {return sizeof(T);}
void Update(const byte *input, size_t length);
byte * CreateUpdateSpace(size_t &size);
void Restart();
void TruncatedFinal(byte *digest, size_t size);
protected:
void SetBlockSize(unsigned int blockSize) {m_data.resize(blockSize / sizeof(HashWordType));}
void SetStateSize(unsigned int stateSize) {m_digest.resize(stateSize / sizeof(HashWordType));}
T GetBitCountHi() const {return (m_countLo >> (8*sizeof(T)-3)) + (m_countHi << 3);}
T GetBitCountLo() const {return m_countLo << 3;}
void PadLastBlock(unsigned int lastBlockSize, byte padFirst=0x80);
virtual void Init() =0;
virtual ByteOrder GetByteOrder() const =0;
virtual void HashEndianCorrectedBlock(const HashWordType *data) =0;
virtual size_t HashMultipleBlocks(const T *input, size_t length);
void HashBlock(const HashWordType *input) {HashMultipleBlocks(input, BlockSize());}
SecBlock<T> m_data; // Data buffer
SecBlock<T> m_digest; // Message digest
private:
T m_countLo, m_countHi;
};
#ifdef WORD64_AVAILABLE
CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word64, HashTransformation>;
CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word64, MessageAuthenticationCode>;
#endif
CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word32, HashTransformation>;
CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word32, MessageAuthenticationCode>;
//! _
template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, class T_Base = HashTransformation>
class CRYPTOPP_NO_VTABLE IteratedHash : public IteratedHashBase<T_HashWordType, T_Base>
{
public:
typedef T_Endianness ByteOrderClass;
typedef T_HashWordType HashWordType;
enum {BLOCKSIZE = T_BlockSize};
CRYPTOPP_COMPILE_ASSERT((BLOCKSIZE & (BLOCKSIZE - 1)) == 0); // blockSize is a power of 2
ByteOrder GetByteOrder() const {return T_Endianness::ToEnum();}
inline static void CorrectEndianess(HashWordType *out, const HashWordType *in, size_t byteCount)
{
ConditionalByteReverse(T_Endianness::ToEnum(), out, in, byteCount);
}
protected:
IteratedHash() {this->SetBlockSize(T_BlockSize);}
};
//! _
template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, unsigned int T_StateSize, class T_Transform, unsigned int T_DigestSize = T_StateSize>
class CRYPTOPP_NO_VTABLE IteratedHashWithStaticTransform
: public ClonableImpl<T_Transform, AlgorithmImpl<IteratedHash<T_HashWordType, T_Endianness, T_BlockSize>, T_Transform> >
{
public:
enum {DIGESTSIZE = T_DigestSize};
unsigned int DigestSize() const {return DIGESTSIZE;};
protected:
IteratedHashWithStaticTransform()
{
this->SetStateSize(T_StateSize);
Init();
}
void HashEndianCorrectedBlock(const T_HashWordType *data) {T_Transform::Transform(this->m_digest, data);}
void Init() {T_Transform::InitState(this->m_digest);}
};
NAMESPACE_END
#endif