Base class for additive stream ciphers with SymmetricCipher interface. More...

#include <strciphr.h>

Inheritance diagram for AdditiveCipherTemplate< BASE >:

Public Types
typedef BASE::PolicyInterface	PolicyInterface

Public Types inherited from AbstractPolicyHolder< POLICY_INTERFACE, BASE >
typedef POLICY_INTERFACE	PolicyInterface

Public Member Functions
void	GenerateBlock (byte *output, size_t size)
	Generate random array of bytes.

void	ProcessData (byte outString, const byte inString, size_t length)
	Apply keystream to data.

void	Resynchronize (const byte *iv, int length=-1)
	Resynchronize the cipher.

unsigned int	OptimalBlockSize () const
	Provides number of ideal bytes to process.

unsigned int	GetOptimalNextBlockSize () const
	Provides number of ideal bytes to process.

unsigned int	OptimalDataAlignment () const
	Provides number of ideal data alignment.

bool	IsSelfInverting () const
	Determines if the cipher is self inverting.

bool	IsForwardTransformation () const
	Determines if the cipher is a forward transformation.

bool	IsRandomAccess () const
	Flag indicating random access.

void	Seek (lword position)
	Seeks to a random position in the stream.

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

Public Member Functions inherited from RandomNumberGenerator
virtual void	IncorporateEntropy (const byte *input, size_t length)
	Update RNG state with additional unpredictable values.

virtual bool	CanIncorporateEntropy () const
	Determines if a generator can accept additional entropy.

virtual byte	GenerateByte ()
	Generate new random byte and return it.

virtual unsigned int	GenerateBit ()
	Generate new random bit and return it.

virtual word32	GenerateWord32 (word32 min=0, word32 max=0xffffffffUL)
	Generate a random 32 bit word in the range min to max, inclusive.

virtual void	GenerateIntoBufferedTransformation (BufferedTransformation &target, const std::string &channel, lword length)
	Generate random bytes into a BufferedTransformation.

virtual void	DiscardBytes (size_t n)
	Generate and discard n bytes.

template<class IT >
void	Shuffle (IT begin, IT end)
	Randomly shuffle the specified array.

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.

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

Detailed Description

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
class AdditiveCipherTemplate< BASE >

Base class for additive stream ciphers with SymmetricCipher interface.

Template Parameters

BASE	AbstractPolicyHolder base class

Definition at line 297 of file strciphr.h.

Member Typedef Documentation

◆ PolicyInterface

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

typedef BASE::PolicyInterface AdditiveCipherTemplate< BASE >::PolicyInterface

Definition at line 387 of file strciphr.h.

Constructor & Destructor Documentation

◆ ~AdditiveCipherTemplate()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

virtual AdditiveCipherTemplate< BASE >::~AdditiveCipherTemplate ( )

inlinevirtual

Definition at line 300 of file strciphr.h.

◆ AdditiveCipherTemplate()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

AdditiveCipherTemplate< BASE >::AdditiveCipherTemplate ( )

inline

Definition at line 301 of file strciphr.h.

Member Function Documentation

◆ GenerateBlock()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

void AdditiveCipherTemplate< BASE >::GenerateBlock	(	byte *	output,
		size_t	size )

virtual

Generate random array of bytes.

Parameters

output	the byte buffer
size	the length of the buffer, in bytes

All generated values are uniformly distributed over the range specified within the constraints of a particular generator.

Reimplemented from RandomNumberGenerator.

◆ ProcessData()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

void AdditiveCipherTemplate< 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 of 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);

You should use distinct buffers for inString and outString. If the buffers are the same, then the data will be copied to an internal buffer to avoid GCC alias violations. The internal copy will impact performance.

See also: Issue 1088, 36% loss of performance with AES, Issue 1010, HIGHT cipher troubles with FileSource

◆ Resynchronize()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

void AdditiveCipherTemplate< 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

◆ OptimalBlockSize()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

unsigned int AdditiveCipherTemplate< 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 340 of file strciphr.h.

◆ GetOptimalNextBlockSize()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

unsigned int AdditiveCipherTemplate< 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 346 of file strciphr.h.

◆ OptimalDataAlignment()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

unsigned int AdditiveCipherTemplate< 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 351 of file strciphr.h.

◆ IsSelfInverting()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

bool AdditiveCipherTemplate< 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 355 of file strciphr.h.

◆ IsForwardTransformation()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

bool AdditiveCipherTemplate< BASE >::IsForwardTransformation ( ) const

inline

Determines if the cipher is a forward transformation.

Returns: true if the stream cipher is a forward transformation, false otherwise

Definition at line 359 of file strciphr.h.

◆ IsRandomAccess()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

bool AdditiveCipherTemplate< BASE >::IsRandomAccess ( ) const

inline

Flag indicating random access.

Returns: true if the cipher is seekable, false otherwise

See also: Seek()

Definition at line 364 of file strciphr.h.

◆ Seek()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

void AdditiveCipherTemplate< BASE >::Seek ( lword position )

Seeks to a random position in the stream.

Parameters

position the absolute position in the stream

See also: IsRandomAccess()

◆ AlgorithmProvider()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>

std::string AdditiveCipherTemplate< BASE >::AlgorithmProvider ( ) const

inlinevirtual

Retrieve the provider of this algorithm.

Returns: the algorithm provider

The algorithm provider can be a name like "C++", "SSE", "NEON", "AESNI", "ARMv8" and "Power8". C++ is standard C++ code. Other labels, like SSE, usually indicate a specialized implementation using instructions from a higher instruction set architecture (ISA). Future labels may include external hardware like a hardware security module (HSM).

Generally speaking Wei Dai's original IA-32 ASM code falls under "SSE2". Labels like "SSSE3" and "SSE4.1" follow after Wei's code and use intrinsics instead of ASM.

Algorithms which combine different instructions or ISAs provide the dominant one. For example on x86 AES/GCM returns "AESNI" rather than "CLMUL" or "AES+SSE4.1" or "AES+CLMUL" or "AES+SSE4.1+CLMUL".

Note: Provider is not universally implemented yet.

Reimplemented from Algorithm.

Definition at line 385 of file strciphr.h.

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

strciphr.h

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ PolicyInterface

Constructor & Destructor Documentation

◆ ~AdditiveCipherTemplate()

◆ AdditiveCipherTemplate()

Member Function Documentation

◆ GenerateBlock()

◆ ProcessData()

◆ Resynchronize()

◆ OptimalBlockSize()

◆ GetOptimalNextBlockSize()

◆ OptimalDataAlignment()

◆ IsSelfInverting()

◆ IsForwardTransformation()

◆ IsRandomAccess()

◆ Seek()

◆ AlgorithmProvider()