CFB_CipherTemplate< BASE > Class Template Reference

Base class for feedback based stream ciphers with SymmetricCipher interface. More...

#include <strciphr.h>

Inheritance diagram for CFB_CipherTemplate< BASE >:

Collaboration diagram for CFB_CipherTemplate< BASE >:

Public Types
typedef BASE::PolicyInterface	PolicyInterface

Public Member Functions
void	ProcessData (byte *outString, const byte *inString, size_t length)
	Apply keystream to data. More...
void	Resynchronize (const byte *iv, int length=-1)
	Resynchronize the cipher. More...
unsigned int	OptimalBlockSize () const
	Provides number of ideal bytes to process. More...
unsigned int	GetOptimalNextBlockSize () const
	Provides number of ideal bytes to process. More...
unsigned int	OptimalDataAlignment () const
	Provides number of ideal data alignment. More...
bool	IsRandomAccess () const
	Flag indicating random access. More...
bool	IsSelfInverting () const
	Determines if the cipher is self inverting. More...

Protected Member Functions
virtual void	CombineMessageAndShiftRegister (byte *output, byte *reg, const byte *message, size_t length)=0
void	UncheckedSetKey (const byte *key, unsigned int length, const NameValuePairs &params)

Protected Attributes
size_t	m_leftOver

Detailed Description

template<class BASE>
class CFB_CipherTemplate< BASE >

Base class for feedback based stream ciphers with SymmetricCipher interface.

Template Parameters

BASE	AbstractPolicyHolder base class

Definition at line 489 of file strciphr.h.

Member Typedef Documentation

template<class BASE >

typedef BASE::PolicyInterface CFB_CipherTemplate< BASE >::PolicyInterface

Definition at line 538 of file strciphr.h.

Member Function Documentation

template<class BASE >

virtual void CFB_CipherTemplate< BASE >::CombineMessageAndShiftRegister ( byte *  output, byte *  reg, const byte *  message, size_t  length  )

protectedpure virtual

Implemented in CFB_DecryptionTemplate< BASE >, and CFB_EncryptionTemplate< BASE >.

template<class BASE >

unsigned int CFB_CipherTemplate< BASE >::GetOptimalNextBlockSize ( ) const

inline

Provides number of ideal bytes to process.

Returns

the ideal number of bytes to process

Internally, the default implementation returns remaining unprocessed bytes

See also

GetBytesPerIteration() and OptimalBlockSize()

Definition at line 522 of file strciphr.h.

template<class BASE >

bool CFB_CipherTemplate< BASE >::IsRandomAccess ( ) const

inline

Flag indicating random access.

Returns

true if the cipher is seekable, false otherwise

See also

Seek()

Definition at line 532 of file strciphr.h.

template<class BASE >

bool CFB_CipherTemplate< BASE >::IsSelfInverting ( ) const

inline

Determines if the cipher is self inverting.

Returns

true if the stream cipher is self inverting, false otherwise

Definition at line 536 of file strciphr.h.

template<class BASE >

unsigned int CFB_CipherTemplate< BASE >::OptimalBlockSize ( ) const

inline

Provides number of ideal bytes to process.

Returns

the ideal number of bytes to process

Internally, the default implementation returns GetBytesPerIteration()

See also

GetBytesPerIteration() and GetOptimalNextBlockSize()

Definition at line 516 of file strciphr.h.

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template<class BASE >

unsigned int CFB_CipherTemplate< BASE >::OptimalDataAlignment ( ) const

inline

Provides number of ideal data alignment.

Returns

the ideal data alignment, in bytes

See also

GetAlignment() and OptimalBlockSize()

Definition at line 527 of file strciphr.h.

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template<class BASE >

void CFB_CipherTemplate< BASE >::ProcessData	(	byte *	outString,
		const byte *	inString,
		size_t	length
	)

Apply keystream to data.

Parameters

outString	a buffer to write the transformed data
inString	a buffer to read the data
length	the size fo the buffers, in bytes

This is the primary method to operate a stream cipher. For example:

    size_t size = 30;
    byte plain[size] = "Do or do not; there is no try";
    byte cipher[size];
    ...
    ChaCha20 chacha(key, keySize);
    chacha.ProcessData(cipher, plain, size);

Definition at line 177 of file strciphr.cpp.

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template<class BASE >

void CFB_CipherTemplate< BASE >::Resynchronize	(	const byte *	iv,
		int	length = -1
	)

Resynchronize the cipher.

Parameters

iv	a byte array used to resynchronize the cipher
length	the size of the IV array

Definition at line 169 of file strciphr.cpp.

template<class BASE >

void CFB_CipherTemplate< BASE >::UncheckedSetKey ( const byte *  key, unsigned int  length, const NameValuePairs &  params  )

protected

Definition at line 153 of file strciphr.cpp.

Member Data Documentation

template<class BASE >

size_t CFB_CipherTemplate< BASE >::m_leftOver

protected

Definition at line 545 of file strciphr.h.

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

• src/cryptopp/strciphr.h
• src/cryptopp/strciphr.cpp