Keccak message digest base class. More...

#include <keccak.h>

Inheritance diagram for Keccak:

Public Member Functions
unsigned int	DigestSize () const
	Provides the digest size of the hash.

unsigned int	OptimalDataAlignment () const
	Provides input and output data alignment for optimal performance.

void	Update (const byte *input, size_t length)
	Updates a hash with additional input.

void	Restart ()
	Restart the hash.

void	TruncatedFinal (byte *hash, size_t size)
	Computes the hash of the current message.

Public Member Functions inherited from HashTransformation
HashTransformation &	Ref ()
	Provides a reference to this object.

virtual byte *	CreateUpdateSpace (size_t &size)
	Request space which can be written into by the caller.

virtual void	Final (byte *digest)
	Computes the hash of the current message.

unsigned int	TagSize () const
	Provides the tag size of the hash.

virtual unsigned int	BlockSize () const
	Provides the block size of the compression function.

virtual unsigned int	OptimalBlockSize () const
	Provides the input block size most efficient for this hash.

virtual void	CalculateDigest (byte digest, const byte input, size_t length)
	Updates the hash with additional input and computes the hash of the current message.

virtual bool	Verify (const byte *digest)
	Verifies the hash of the current message.

virtual bool	VerifyDigest (const byte digest, const byte input, size_t length)
	Updates the hash with additional input and verifies the hash of the current message.

virtual void	CalculateTruncatedDigest (byte digest, size_t digestSize, const byte input, size_t length)
	Updates the hash with additional input and computes the hash of the current message.

virtual bool	TruncatedVerify (const byte *digest, size_t digestLength)
	Verifies the hash of the current message.

virtual bool	VerifyTruncatedDigest (const byte digest, size_t digestLength, const byte input, size_t length)
	Updates the hash with additional input and verifies the hash of the current message.

Public Member Functions inherited from Algorithm
	Algorithm (bool checkSelfTestStatus=true)
	Interface for all crypto algorithms.

virtual std::string	AlgorithmName () const
	Provides the name of this algorithm.

virtual std::string	AlgorithmProvider () const
	Retrieve the provider of this algorithm.

Public Member Functions inherited from Clonable
virtual Clonable *	Clone () const
	Copies this object.

Detailed Description

Keccak message digest base class.

The Crypto++ Keccak implementation uses F1600 with XOF d=0x01. FIPS 202 conformance (XOF d=0x06) is available in SHA3 classes.

Keccak is the base class for Keccak_224, Keccak_256, Keccak_384 and Keccak_512. Library users should instantiate a derived class, and only use Keccak as a base class reference or pointer.

Keccak will likely change in the future to accommodate extensibility of the round function and the XOF functions.

Perform the following to specify a different digest size. The class will use F1600, XOF d=0x01, and a new value for r() (which will be 200-2*24 = 152).

  Keccack_192 : public Keccack
  {
    public:
      CRYPTOPP_CONSTANT(DIGESTSIZE = 24);
      Keccack_192() : Keccack(DIGESTSIZE) {}
  };

See also: SHA3, Keccak_224, Keccak_256, Keccak_384 and Keccak_512.

Since: Crypto++ 5.6.4

Definition at line 40 of file keccak.h.

Member Function Documentation

◆ DigestSize()

unsigned int Keccak::DigestSize ( ) const

inlinevirtual

Provides the digest size of the hash.

Returns: the digest size of the hash.

Implements HashTransformation.

Definition at line 54 of file keccak.h.

◆ OptimalDataAlignment()

unsigned int Keccak::OptimalDataAlignment ( ) const

inlinevirtual

Provides input and output data alignment for optimal performance.

Returns: the input data alignment that provides optimal performance

See also: GetAlignment() and OptimalBlockSize()

Reimplemented from HashTransformation.

Definition at line 55 of file keccak.h.

◆ Update()

void Keccak::Update	(	const byte *	input,
		size_t	length
	)

virtual

Updates a hash with additional input.

Parameters

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

Implements HashTransformation.

Definition at line 28 of file keccak.cpp.

◆ Restart()

void Keccak::Restart ( )

virtual

Restart the hash.

Discards the current state, and restart for a new message

Reimplemented from HashTransformation.

Definition at line 49 of file keccak.cpp.

◆ TruncatedFinal()

void Keccak::TruncatedFinal	(	byte *	digest,
		size_t	digestSize
	)

virtual

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.

Precondition: COUNTOF(digest) <= DigestSize() or COUNTOF(digest) <= HASH::DIGESTSIZE ensures the output byte buffer is a valid size.

Implements HashTransformation.

Definition at line 55 of file keccak.cpp.

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

Public Member Functions

Detailed Description

Member Function Documentation

◆ DigestSize()

◆ OptimalDataAlignment()

◆ Update()

◆ Restart()

◆ TruncatedFinal()