IteratedHashBase< T, BASE > Class Template Reference

Iterated hash base class. More...

#include <iterhash.h>

Inheritance diagram for IteratedHashBase< T, BASE >:

Public Types
typedef T	HashWordType

Public Member Functions
	IteratedHashBase ()
	Construct an IteratedHashBase. More...
unsigned int	OptimalBlockSize () const
	Provides the input block size most efficient for this cipher. More...
unsigned int	OptimalDataAlignment () const
	Provides input and output data alignment for optimal performance. More...
void	Update (const byte *input, size_t length)
	Updates a hash with additional input. More...
byte *	CreateUpdateSpace (size_t &size)
	Requests space which can be written into by the caller. More...
void	Restart ()
	Restart the hash. More...
void	TruncatedFinal (byte *digest, size_t digestSize)
	Computes the hash of the current message. More...
virtual std::string	AlgorithmProvider () const
	Retrieve the provider of this algorithm. More...

Detailed Description

template<class T, class BASE>
class IteratedHashBase< T, BASE >

Iterated hash base class.

Template Parameters

T	Hash word type
BASE	HashTransformation derived class

IteratedHashBase provides an interface for block-based iterated hashes

See also

HashTransformation, MessageAuthenticationCode

Definition at line 38 of file iterhash.h.

Member Typedef Documentation

HashWordType

template<class T , class BASE >

typedef T IteratedHashBase< T, BASE >::HashWordType

Definition at line 41 of file iterhash.h.

Constructor & Destructor Documentation

~IteratedHashBase()

template<class T , class BASE >

virtual IteratedHashBase< T, BASE >::~IteratedHashBase ( )

inlinevirtual

Definition at line 43 of file iterhash.h.

IteratedHashBase()

template<class T , class BASE >

IteratedHashBase< T, BASE >::IteratedHashBase ( )

inline

Construct an IteratedHashBase.

Definition at line 46 of file iterhash.h.

Member Function Documentation

OptimalBlockSize()

template<class T , class BASE >

unsigned int IteratedHashBase< T, BASE >::OptimalBlockSize ( ) const

inline

Provides the input block size most efficient for this cipher.

Returns

The input block size that is most efficient for the cipher

The base class implementation returns MandatoryBlockSize().

Note

Optimal input length is n * OptimalBlockSize() - GetOptimalBlockSizeUsed() for any n > 0.

Definition at line 53 of file iterhash.h.

OptimalDataAlignment()

template<class T , class BASE >

unsigned int IteratedHashBase< T, BASE >::OptimalDataAlignment ( ) const

inline

Provides input and output data alignment for optimal performance.

Returns

the input data alignment that provides optimal performance

OptimalDataAlignment returns the natural alignment of the hash word.

Definition at line 58 of file iterhash.h.

Update()

template<class T , class BASE >

void IteratedHashBase< T, BASE >::Update	(	const byte *	input,
		size_t	length
	)

Updates a hash with additional input.

Parameters

input	the additional input as a buffer
length	the size of the buffer, in bytes

Definition at line 13 of file iterhash.cpp.

CreateUpdateSpace()

template<class T , class BASE >

byte * IteratedHashBase< T, BASE >::CreateUpdateSpace

(

size_t &

size

)

Requests space which can be written into by the caller.

Parameters

size	the requested size of the buffer

The purpose of this method is to help avoid extra memory allocations.

size is an IN and 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.

The base class implementation sets size to 0 and returns NULL.

Note

Some objects, like ArraySink, cannot create a space because its fixed.

Definition at line 85 of file iterhash.cpp.

Restart()

template<class T , class BASE >

void IteratedHashBase< T, BASE >::Restart

Restart the hash.

Discards the current state, and restart for a new message

Definition at line 159 of file iterhash.cpp.

TruncatedFinal()

template<class T , class BASE >

void IteratedHashBase< T, BASE >::TruncatedFinal	(	byte *	digest,
		size_t	digestSize
	)

Computes the hash of the current message.

Parameters

digest	a pointer to the buffer to receive the hash
digestSize	the size of the truncated digest, in bytes

TruncatedFinal() calls Final() and then copies digestSize bytes to digest. The hash is restarted the hash for the next message.

Reimplemented in Weak::PanamaHash< LittleEndian >.

Definition at line 165 of file iterhash.cpp.

AlgorithmProvider()

template<class T , class BASE >

virtual std::string IteratedHashBase< T, BASE >::AlgorithmProvider ( ) const

inlinevirtual

Retrieve the provider of this algorithm.

Returns

the algorithm provider

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.

Reimplemented in Weak::PanamaHash< B >, Weak::PanamaHash< LittleEndian >, SHA1, SHA256, SHA224, SHA512, SHA384, Tiger, VMAC_Base, and Whirlpool.

Definition at line 94 of file iterhash.h.

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The documentation for this class was generated from the following files:

• iterhash.h
• iterhash.cpp