StreamTransformation Class Reference

#include <cryptlib.h>

Inheritance diagram for StreamTransformation:

Algorithm Clonable PublicBlumBlumShub SymmetricCipher BlumBlumShub ARC4_Base CipherModeBase MARC4_Base SimpleKeyingInterfaceImpl< ARC4_Base, ARC4_Base > BlockOrientedCipherModeBase ModePolicyCommonTemplate< POLICY_INTERFACE > ModePolicyCommonTemplate< AdditiveCipherAbstractPolicy > ModePolicyCommonTemplate< CFB_CipherAbstractPolicy > SimpleKeyingInterfaceImpl< MARC4_Base, MARC4_Base > AlgorithmImpl< SimpleKeyingInterfaceImpl< ARC4_Base, ARC4_Base >, ARC4_Base > CBC_ModeBase ECB_OneWay CTR_ModePolicy OFB_ModePolicy CFB_ModePolicy AlgorithmImpl< SimpleKeyingInterfaceImpl< MARC4_Base, MARC4_Base >, MARC4_Base > SymmetricCipherFinal< ARC4_Base > CBC_Decryption CBC_Encryption SymmetricCipherFinal< MARC4_Base > ARC4 CBC_CTS_Decryption CBC_CTS_Encryption MARC4 List of all members.

Detailed Description

interface for the data processing part of stream ciphers

Definition at line 460 of file cryptlib.h.

Public Member Functions

StreamTransformationRef ()
 return a reference to this object,
virtual unsigned int MandatoryBlockSize () const
 returns block size, if input must be processed in blocks, otherwise 1
virtual unsigned int OptimalBlockSize () const
 returns the input block size that is most efficient for this cipher
virtual unsigned int GetOptimalBlockSizeUsed () const
 returns how much of the current block is used up
virtual unsigned int OptimalDataAlignment () const
 returns how input should be aligned for optimal performance
virtual void ProcessData (byte *outString, const byte *inString, size_t length)=0
 encrypt or decrypt an array of bytes of specified length
virtual void ProcessLastBlock (byte *outString, const byte *inString, size_t length)
 for ciphers where the last block of data is special, encrypt or decrypt the last block of data
virtual unsigned int MinLastBlockSize () const
 returns the minimum size of the last block, 0 indicating the last block is not special
void ProcessString (byte *inoutString, size_t length)
 same as ProcessData(inoutString, inoutString, length)
void ProcessString (byte *outString, const byte *inString, size_t length)
 same as ProcessData(outString, inString, length)
byte ProcessByte (byte input)
 implemented as {ProcessData(&input, &input, 1); return input;}
virtual bool IsRandomAccess () const=0
 returns whether this cipher supports random access
virtual void Seek (lword n)
 for random access ciphers, seek to an absolute position
virtual bool IsSelfInverting () const=0
 returns whether this transformation is self-inverting (e.g. xor with a keystream)
virtual bool IsForwardTransformation () const=0
 returns whether this is an encryption object
virtual std::string AlgorithmName () const
 returns name of this algorithm, not universally implemented yet
virtual ClonableClone () const
 this is not implemented by most classes yet


Member Function Documentation

StreamTransformation& StreamTransformation::Ref (  )  [inline]

return a reference to this object,

This function is useful for passing a temporary StreamTransformation object to a function that takes a non-const reference.

Definition at line 466 of file cryptlib.h.

virtual unsigned int StreamTransformation::OptimalBlockSize (  )  const [inline, virtual]

returns the input block size that is most efficient for this cipher

Note:
optimal input length is n * OptimalBlockSize() - GetOptimalBlockSizeUsed() for any n > 0

Reimplemented in ECB_OneWay.

Definition at line 473 of file cryptlib.h.

Referenced by StreamTransformationFilter::FirstPut().

virtual void StreamTransformation::ProcessData ( byte *  outString,
const byte *  inString,
size_t  length 
) [pure virtual]

encrypt or decrypt an array of bytes of specified length

Note:
either inString == outString, or they don't overlap

Implemented in ARC4_Base, PublicBlumBlumShub, and BlockOrientedCipherModeBase.

Referenced by StreamTransformationFilter::LastPut(), and ProcessLastBlock().

void StreamTransformation::ProcessLastBlock ( byte *  outString,
const byte *  inString,
size_t  length 
) [virtual]

for ciphers where the last block of data is special, encrypt or decrypt the last block of data

For now the only use of this function is for CBC-CTS mode.

Reimplemented in CBC_CTS_Encryption, and CBC_CTS_Decryption.

Definition at line 107 of file cryptlib.cpp.

References MandatoryBlockSize(), MinLastBlockSize(), and ProcessData().

Referenced by StreamTransformationFilter::LastPut().


The documentation for this class was generated from the following files:
Generated on Sat Dec 23 02:07:35 2006 for Crypto++ by  doxygen 1.5.1-p1