Crypto++  5.6.5
Free C++ class library of cryptographic schemes
Public Member Functions | Static Public Member Functions | List of all members
Keccak Class Reference

Keccak message digest base class. More...

+ Inheritance diagram for Keccak:

Public Member Functions

 Keccak (unsigned int digestSize)
 Construct a Keccak. More...
 
unsigned int DigestSize () const
 Provides the digest size of the hash. More...
 
std::string AlgorithmName () const
 Provides the name of this algorithm. 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...
 
void Restart ()
 Restart the hash. More...
 
void TruncatedFinal (byte *hash, size_t size)
 Computes the hash of the current message. More...
 
- Public Member Functions inherited from HashTransformation
HashTransformationRef ()
 Provides a reference to this object. More...
 
virtual byte * CreateUpdateSpace (size_t &size)
 Request space which can be written into by the caller. More...
 
virtual void Final (byte *digest)
 Computes the hash of the current message. More...
 
unsigned int TagSize () const
 Provides the tag size of the hash. More...
 
virtual unsigned int BlockSize () const
 Provides the block size of the compression function. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this hash. More...
 
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. More...
 
virtual bool Verify (const byte *digest)
 Verifies the hash of the current message. More...
 
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. More...
 
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. More...
 
virtual bool TruncatedVerify (const byte *digest, size_t digestLength)
 Verifies the hash of the current message. More...
 
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. More...
 
- Public Member Functions inherited from Algorithm
 Algorithm (bool checkSelfTestStatus=true)
 Interface for all crypto algorithms. More...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. More...
 

Static Public Member Functions

static const char * StaticAlgorithmName ()
 

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 vaue 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 41 of file keccak.h.

Constructor & Destructor Documentation

◆ Keccak()

Keccak::Keccak ( unsigned int  digestSize)
inline

Construct a Keccak.

Parameters
digestSizethe digest size, in bytes

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.

Since
Crypto++ 5.6.4

Definition at line 50 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 51 of file keccak.h.

◆ AlgorithmName()

std::string Keccak::AlgorithmName ( ) const
inlinevirtual

Provides the name of this algorithm.

Returns
the standard algorithm name

The standard algorithm name can be a name like AES or AES/GCM. Some algorithms do not have standard names yet. For example, there is no standard algorithm name for Shoup's ECIES.

Note
AlgorithmName is not universally implemented yet

Reimplemented from Algorithm.

Definition at line 52 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

Reimplemented from HashTransformation.

Definition at line 54 of file keccak.h.

◆ Update()

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

Updates a hash with additional input.

Parameters
inputthe additional input as a buffer
lengththe size of the buffer, in bytes

Implements HashTransformation.

Definition at line 252 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 273 of file keccak.cpp.

◆ TruncatedFinal()

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

Computes the hash of the current message.

Parameters
digesta pointer to the buffer to receive the hash
digestSizethe size of the truncated digest, in bytes

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

Implements HashTransformation.

Definition at line 279 of file keccak.cpp.


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