Crypto++  5.6.4
Free C++ class library of cryptographic schemes
Public Member Functions | List of all members
StreamTransformation Class Referenceabstract

Interface for the data processing portion of stream ciphers. More...

+ Inheritance diagram for StreamTransformation:

Public Member Functions

StreamTransformationRef ()
 Provides a reference to this object. More...
 
virtual unsigned int MandatoryBlockSize () const
 Provides the mandatory block size of the cipher. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this cipher. More...
 
virtual unsigned int GetOptimalBlockSizeUsed () const
 Provides the number of bytes used in the current block when processing at optimal block size. More...
 
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance. More...
 
virtual void ProcessData (byte *outString, const byte *inString, size_t length)=0
 Encrypt or decrypt an array of bytes. More...
 
virtual void ProcessLastBlock (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt the last block of data. More...
 
virtual unsigned int MinLastBlockSize () const
 Provides the size of the last block. More...
 
void ProcessString (byte *inoutString, size_t length)
 Encrypt or decrypt a string of bytes. More...
 
void ProcessString (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt a string of bytes. More...
 
byte ProcessByte (byte input)
 Encrypt or decrypt a byte. More...
 
virtual bool IsRandomAccess () const =0
 Determines whether the cipher supports random access. More...
 
virtual void Seek (lword pos)
 Seek to an absolute position. More...
 
virtual bool IsSelfInverting () const =0
 Determines whether the cipher is self-inverting. More...
 
virtual bool IsForwardTransformation () const =0
 Determines if the cipher is being operated in its forward direction. More...
 
- Public Member Functions inherited from Algorithm
 Algorithm (bool checkSelfTestStatus=true)
 Interface for all crypto algorithms. More...
 
virtual std::string AlgorithmName () const
 Provides the name of this algorithm. More...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. More...
 

Detailed Description

Interface for the data processing portion of stream ciphers.

See also
StreamTransformationFilter()

Definition at line 822 of file cryptlib.h.

Member Function Documentation

StreamTransformation& StreamTransformation::Ref ( )
inline

Provides a reference to this object.

Returns
A reference to this object

Useful for passing a temporary object to a function that takes a non-const reference

Definition at line 832 of file cryptlib.h.

virtual unsigned int StreamTransformation::MandatoryBlockSize ( ) const
inlinevirtual

Provides the mandatory block size of the cipher.

Returns
The block size of the cipher if input must be processed in blocks, 1 otherwise

Reimplemented in BlockOrientedCipherModeBase.

Definition at line 836 of file cryptlib.h.

virtual unsigned int StreamTransformation::OptimalBlockSize ( ) const
inlinevirtual

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.

Reimplemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, and ECB_OneWay.

Definition at line 843 of file cryptlib.h.

virtual unsigned int StreamTransformation::GetOptimalBlockSizeUsed ( ) const
inlinevirtual

Provides the number of bytes used in the current block when processing at optimal block size.

Returns
the number of bytes used in the current block when processing at the optimal block size

Definition at line 847 of file cryptlib.h.

unsigned int StreamTransformation::OptimalDataAlignment ( ) const
virtual

Provides input and output data alignment for optimal performance.

Returns
the input data alignment that provides optimal performance

Reimplemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, CipherModeBase, GCM_Base, CCM_Base, and EAX_Base.

Definition at line 234 of file cryptlib.cpp.

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

Encrypt or decrypt an array of bytes.

Parameters
outStringthe output byte buffer
inStringthe input byte buffer
lengththe size of the input and output byte buffers, in bytes

Either inString == outString, or they must not overlap.

Implemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, CBC_Decryption, CBC_Encryption, ECB_OneWay, AuthenticatedSymmetricCipherBase, Weak::ARC4_Base, and PublicBlumBlumShub.

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

Encrypt or decrypt the last block of data.

Parameters
outStringthe output byte buffer
inStringthe input byte buffer
lengththe size of the input and output byte buffers, in bytes ProcessLastBlock is used when the last block of data is special. Currently the only use of this function is CBC-CTS mode.

Reimplemented in CBC_CTS_Decryption, and CBC_CTS_Encryption.

Definition at line 244 of file cryptlib.cpp.

virtual unsigned int StreamTransformation::MinLastBlockSize ( ) const
inlinevirtual

Provides the size of the last block.

Returns
the minimum size of the last block

MinLastBlockSize() returns the minimum size of the last block. 0 indicates the last block is not special.

Reimplemented in CBC_CTS_Decryption, CBC_CTS_Encryption, and CBC_ModeBase.

Definition at line 872 of file cryptlib.h.

void StreamTransformation::ProcessString ( byte *  inoutString,
size_t  length 
)
inline

Encrypt or decrypt a string of bytes.

Parameters
inoutStringthe string to process
lengththe size of the inoutString, in bytes

Internally, the base class implementation calls ProcessData().

Definition at line 878 of file cryptlib.h.

void StreamTransformation::ProcessString ( byte *  outString,
const byte *  inString,
size_t  length 
)
inline

Encrypt or decrypt a string of bytes.

Parameters
outStringthe output string to process
inStringthe input string to process
lengththe size of the input and output strings, in bytes

Internally, the base class implementation calls ProcessData().

Definition at line 886 of file cryptlib.h.

byte StreamTransformation::ProcessByte ( byte  input)
inline

Encrypt or decrypt a byte.

Parameters
inputthe input byte to process

Internally, the base class implementation calls ProcessData() with a size of 1.

Definition at line 892 of file cryptlib.h.

virtual bool StreamTransformation::IsRandomAccess ( ) const
pure virtual

Determines whether the cipher supports random access.

Returns
true if the cipher supports random access, false otherwise

Implemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, BlockOrientedCipherModeBase, BlumBlumShub, Weak::ARC4_Base, and AuthenticatedSymmetricCipherBase.

virtual void StreamTransformation::Seek ( lword  pos)
inlinevirtual

Seek to an absolute position.

Parameters
posposition to seek
Exceptions
NotImplemented

The base class implementation throws NotImplemented. The function asserts IsRandomAccess() in debug builds.

Reimplemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, and BlumBlumShub.

Definition at line 904 of file cryptlib.h.

virtual bool StreamTransformation::IsSelfInverting ( ) const
pure virtual

Determines whether the cipher is self-inverting.

Returns
true if the cipher is self-inverting, false otherwise

IsSelfInverting determines whether this transformation is self-inverting (e.g. xor with a keystream).

Implemented in AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > >, BlockOrientedCipherModeBase, Weak::ARC4_Base, PublicBlumBlumShub, and AuthenticatedSymmetricCipherBase.

virtual bool StreamTransformation::IsForwardTransformation ( ) const
pure virtual

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