iterhash.h
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// iterhash.h - originally written and placed in the public domain by Wei Dai
/// \file iterhash.h
/// \brief Base classes for iterated hashes
#ifndef CRYPTOPP_ITERHASH_H
#define CRYPTOPP_ITERHASH_H
#include "cryptlib.h"
#include "secblock.h"
#include "misc.h"
#include "simple.h"
#if CRYPTOPP_MSC_VERSION
# pragma warning(push)
# pragma warning(disable: 4231 4275)
# if (CRYPTOPP_MSC_VERSION >= 1400)
# pragma warning(disable: 6011 6386 28193)
# endif
#endif
NAMESPACE_BEGIN(CryptoPP)
/// \brief 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) {}
};
/// \brief Iterated hash base class
/// \tparam T Hash word type
/// \tparam BASE HashTransformation derived class
/// \details IteratedHashBase provides an interface for block-based iterated hashes
/// \sa HashTransformation, MessageAuthenticationCode
template <class T, class BASE>
class CRYPTOPP_NO_VTABLE IteratedHashBase : public BASE
{
public:
typedef T HashWordType;
virtual ~IteratedHashBase() {}
/// \brief Construct an IteratedHashBase
IteratedHashBase() : m_countLo(0), m_countHi(0) {}
/// \brief Provides the input block size most efficient for this cipher.
/// \return The input block size that is most efficient for the cipher
/// \details The base class implementation returns MandatoryBlockSize().
/// \note Optimal input length is
/// <tt>n * OptimalBlockSize() - GetOptimalBlockSizeUsed()</tt> for any <tt>n > 0</tt>.
unsigned int OptimalBlockSize() const {return this->BlockSize();}
/// \brief Provides input and output data alignment for optimal performance.
/// \return the input data alignment that provides optimal performance
/// \details OptimalDataAlignment returns the natural alignment of the hash word.
unsigned int OptimalDataAlignment() const {return GetAlignmentOf<T>();}
/// \brief Updates a hash with additional input
/// \param input the additional input as a buffer
/// \param length the size of the buffer, in bytes
void Update(const byte *input, size_t length);
/// \brief Requests space which can be written into by the caller
/// \param size the requested size of the buffer
/// \details The purpose of this method is to help avoid extra memory allocations.
/// \details size is an \a IN and \a OUT parameter and used as a hint. When the call is made,
/// size is the requested size of the buffer. When the call returns, size is the size of
/// the array returned to the caller.
/// \details The base class implementation sets size to 0 and returns NULL.
/// \note Some objects, like ArraySink, cannot create a space because its fixed.
byte * CreateUpdateSpace(size_t &size);
/// \brief Restart the hash
/// \details Discards the current state, and restart for a new message
void Restart();
/// \brief Computes the hash of the current message
/// \param digest a pointer to the buffer to receive the hash
/// \param digestSize the size of the truncated digest, in bytes
/// \details TruncatedFinal() calls Final() and then copies digestSize bytes to digest.
/// The hash is restarted the hash for the next message.
void TruncatedFinal(byte *digest, size_t digestSize);
/// \brief Retrieve the provider of this algorithm
/// \return the algorithm provider
/// \details The algorithm provider can be a name like "C++", "SSE", "NEON", "AESNI",
/// "ARMv8" and "Power8". C++ is standard C++ code. Other labels, like SSE,
/// usually indicate a specialized implementation using instructions from a higher
/// instruction set architecture (ISA). Future labels may include external hardware
/// like a hardware security module (HSM).
/// \note Provider is not universally implemented yet.
virtual std::string AlgorithmProvider() const { return "C++"; }
protected:
inline T GetBitCountHi() const
{return (m_countLo >> (8*sizeof(T)-3)) + (m_countHi << 3);}
inline 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, this->BlockSize());}
virtual T* DataBuf() =0;
virtual T* StateBuf() =0;
private:
T m_countLo, m_countHi;
};
/// \brief Iterated hash base class
/// \tparam T_HashWordType Hash word type
/// \tparam T_Endianness Endianness type of hash
/// \tparam T_BlockSize Block size of the hash
/// \tparam T_Base HashTransformation derived class
/// \details IteratedHash provides a default implementation for block-based iterated hashes
/// \sa HashTransformation, 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;
CRYPTOPP_CONSTANT(BLOCKSIZE = T_BlockSize);
// BCB2006 workaround: can't use BLOCKSIZE here
CRYPTOPP_COMPILE_ASSERT((T_BlockSize & (T_BlockSize - 1)) == 0); // blockSize is a power of 2
virtual ~IteratedHash() {}
/// \brief Provides the block size of the hash
/// \return the block size of the hash, in bytes
/// \details BlockSize() returns <tt>T_BlockSize</tt>.
unsigned int BlockSize() const {return T_BlockSize;}
/// \brief Provides the byte order of the hash
/// \return the byte order of the hash as an enumeration
/// \details GetByteOrder() returns <tt>T_Endianness::ToEnum()</tt>.
/// \sa ByteOrder()
ByteOrder GetByteOrder() const {return T_Endianness::ToEnum();}
/// \brief Adjusts the byte ordering of the hash
/// \param out the output buffer
/// \param in the input buffer
/// \param byteCount the size of the buffers, in bytes
/// \details CorrectEndianess() calls ConditionalByteReverse() using <tt>T_Endianness</tt>.
inline void CorrectEndianess(HashWordType *out, const HashWordType *in, size_t byteCount)
{
CRYPTOPP_ASSERT(in != NULLPTR);
CRYPTOPP_ASSERT(out != NULLPTR);
CRYPTOPP_ASSERT(IsAligned<T_HashWordType>(in));
CRYPTOPP_ASSERT(IsAligned<T_HashWordType>(out));
ConditionalByteReverse(T_Endianness::ToEnum(), out, in, byteCount);
}
protected:
enum { Blocks = T_BlockSize/sizeof(T_HashWordType) };
T_HashWordType* DataBuf() {return this->m_data;}
FixedSizeSecBlock<T_HashWordType, Blocks> m_data;
};
/// \brief Iterated hash with a static transformation function
/// \tparam T_HashWordType Hash word type
/// \tparam T_Endianness Endianness type of hash
/// \tparam T_BlockSize Block size of the hash
/// \tparam T_StateSize Internal state size of the hash
/// \tparam T_Transform HashTransformation derived class
/// \tparam T_DigestSize Digest size of the hash
/// \tparam T_StateAligned Flag indicating if state is 16-byte aligned
/// \sa HashTransformation, MessageAuthenticationCode
template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, unsigned int T_StateSize, class T_Transform, unsigned int T_DigestSize = 0, bool T_StateAligned = false>
class CRYPTOPP_NO_VTABLE IteratedHashWithStaticTransform
: public ClonableImpl<T_Transform, AlgorithmImpl<IteratedHash<T_HashWordType, T_Endianness, T_BlockSize>, T_Transform> >
{
public:
CRYPTOPP_CONSTANT(DIGESTSIZE = T_DigestSize ? T_DigestSize : T_StateSize);
virtual ~IteratedHashWithStaticTransform() {}
/// \brief Provides the digest size of the hash
/// \return the digest size of the hash, in bytes
/// \details DigestSize() returns <tt>DIGESTSIZE</tt>.
unsigned int DigestSize() const {return DIGESTSIZE;}
protected:
// https://github.com/weidai11/cryptopp/issues/147#issuecomment-766231864
IteratedHashWithStaticTransform() {IteratedHashWithStaticTransform::Init();}
void HashEndianCorrectedBlock(const T_HashWordType *data) {T_Transform::Transform(this->m_state, data);}
void Init() {T_Transform::InitState(this->m_state);}
enum { Blocks = T_BlockSize/sizeof(T_HashWordType) };
T_HashWordType* StateBuf() {return this->m_state;}
FixedSizeAlignedSecBlock<T_HashWordType, Blocks, T_StateAligned> m_state;
};
#if !defined(__GNUC__) && !defined(__clang__)
CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word64, HashTransformation>;
CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word64, MessageAuthenticationCode>;
CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word32, HashTransformation>;
CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word32, MessageAuthenticationCode>;
#endif
NAMESPACE_END
#if CRYPTOPP_MSC_VERSION
# pragma warning(pop)
#endif
#endif
ClonableImpl
Base class for identifying algorithm.
Definition simple.h:26
FixedSizeAlignedSecBlock
Fixed size stack-based SecBlock with 16-byte alignment.
Definition secblock.h:1259
FixedSizeSecBlock
Fixed size stack-based SecBlock.
Definition secblock.h:1246
HashInputTooLong
Exception thrown when trying to hash more data than is allowed by a hash function.
Definition iterhash.h:26
InvalidDataFormat
Input data was received that did not conform to expected format.
Definition cryptlib.h:218
IteratedHashBase
Iterated hash base class.
Definition iterhash.h:39
IteratedHashBase::OptimalDataAlignment
unsigned int OptimalDataAlignment() const
Provides input and output data alignment for optimal performance.
Definition iterhash.h:58
IteratedHashBase::AlgorithmProvider
virtual std::string AlgorithmProvider() const
Retrieve the provider of this algorithm.
Definition iterhash.h:94
IteratedHashBase::IteratedHashBase
IteratedHashBase()
Construct an IteratedHashBase.
Definition iterhash.h:46
IteratedHashBase::OptimalBlockSize
unsigned int OptimalBlockSize() const
Provides the input block size most efficient for this cipher.
Definition iterhash.h:53
IteratedHash
Iterated hash base class.
Definition iterhash.h:127
IteratedHash::GetByteOrder
ByteOrder GetByteOrder() const
Provides the byte order of the hash.
Definition iterhash.h:147
IteratedHash::CorrectEndianess
void CorrectEndianess(HashWordType *out, const HashWordType *in, size_t byteCount)
Adjusts the byte ordering of the hash.
Definition iterhash.h:154
IteratedHash::BlockSize
unsigned int BlockSize() const
Provides the block size of the hash.
Definition iterhash.h:141
IteratedHashWithStaticTransform
Iterated hash with a static transformation function.
Definition iterhash.h:182
IteratedHashWithStaticTransform::DigestSize
unsigned int DigestSize() const
Provides the digest size of the hash.
Definition iterhash.h:191
CRYPTOPP_STATIC_TEMPLATE_CLASS
#define CRYPTOPP_STATIC_TEMPLATE_CLASS
Instantiate templates in a dynamic library.
Definition config_dll.h:92
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.
ByteOrder
ByteOrder
Provides the byte ordering.
Definition cryptlib.h:148
misc.h
Utility functions for the Crypto++ library.
CRYPTOPP_COMPILE_ASSERT
#define CRYPTOPP_COMPILE_ASSERT(expr)
Compile time assertion.
Definition misc.h:153
ConditionalByteReverse
T ConditionalByteReverse(ByteOrder order, T value)
Reverses bytes in a value depending upon endianness.
Definition misc.h:2417
CryptoPP
Crypto++ library namespace.
Name::BlockSize
const char * BlockSize()
int, in bytes
Definition argnames.h:27
secblock.h
Classes and functions for secure memory allocations.
simple.h
Classes providing basic library services.
CRYPTOPP_ASSERT
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition trap.h:68