Block cipher mode of operation information. More...

#include <modes.h>

Inheritance diagram for CipherModeBase:

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

size_t	MinKeyLength () const
	Returns smallest valid key length.

size_t	MaxKeyLength () const
	Returns largest valid key length.

size_t	DefaultKeyLength () const
	Returns default key length.

size_t	GetValidKeyLength (size_t keylength) const
	Returns a valid key length for the algorithm.

bool	IsValidKeyLength (size_t keylength) const
	Returns whether keylength is a valid key length.

unsigned int	OptimalDataAlignment () const
	Provides input and output data alignment for optimal performance.

unsigned int	IVSize () const
	Returns length of the IV accepted by this object.

virtual IV_Requirement	IVRequirement () const =0
	Minimal requirement for secure IVs.

void	SetCipher (BlockCipher &cipher)
	Set external block cipher.

void	SetCipherWithIV (BlockCipher &cipher, const byte *iv, int feedbackSize=0)
	Set external block cipher and IV.

Public Member Functions inherited from SimpleKeyingInterface
virtual void	SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
	Sets or reset the key of this object.

void	SetKeyWithRounds (const byte *key, size_t length, int rounds)
	Sets or reset the key of this object.

void	SetKeyWithIV (const byte key, size_t length, const byte iv, size_t ivLength)
	Sets or reset the key of this object.

void	SetKeyWithIV (const byte key, size_t length, const byte iv)
	Sets or reset the key of this object.

bool	IsResynchronizable () const
	Determines if the object can be resynchronized.

bool	CanUseRandomIVs () const
	Determines if the object can use random IVs.

bool	CanUsePredictableIVs () const
	Determines if the object can use random but possibly predictable IVs.

bool	CanUseStructuredIVs () const
	Determines if the object can use structured IVs.

unsigned int	DefaultIVLength () const
	Provides the default size of an IV.

virtual unsigned int	MinIVLength () const
	Provides the minimum size of an IV.

virtual unsigned int	MaxIVLength () const
	Provides the maximum size of an IV.

virtual void	Resynchronize (const byte *iv, int ivLength=-1)
	Resynchronize with an IV.

virtual void	GetNextIV (RandomNumberGenerator &rng, byte *iv)
	Retrieves a secure IV for the next message.

Public Member Functions inherited from StreamTransformation
StreamTransformation &	Ref ()
	Provides a reference to this object.

virtual unsigned int	MandatoryBlockSize () const
	Provides the mandatory block size of the cipher.

virtual unsigned int	OptimalBlockSize () const
	Provides the input block size most efficient for this cipher.

virtual unsigned int	GetOptimalBlockSizeUsed () const
	Provides the number of bytes used in the current block when processing at optimal block size.

virtual void	ProcessData (byte outString, const byte inString, size_t length)=0
	Encrypt or decrypt an array of bytes.

virtual size_t	ProcessLastBlock (byte outString, size_t outLength, const byte inString, size_t inLength)
	Encrypt or decrypt the last block of data.

virtual unsigned int	MinLastBlockSize () const
	Provides the size of the last block.

virtual bool	IsLastBlockSpecial () const
	Determines if the last block receives special processing.

void	ProcessString (byte *inoutString, size_t length)
	Encrypt or decrypt a string of bytes.

void	ProcessString (byte outString, const byte inString, size_t length)
	Encrypt or decrypt a string of bytes.

byte	ProcessByte (byte input)
	Encrypt or decrypt a byte.

virtual bool	IsRandomAccess () const =0
	Determines whether the cipher supports random access.

virtual void	Seek (lword pos)
	Seek to an absolute position.

virtual bool	IsSelfInverting () const =0
	Determines whether the cipher is self-inverting.

virtual bool	IsForwardTransformation () const =0
	Determines if the cipher is being operated in its forward direction.

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.

Additional Inherited Members
Public Types inherited from SimpleKeyingInterface
enum	IV_Requirement { UNIQUE_IV = 0 , RANDOM_IV , UNPREDICTABLE_RANDOM_IV , INTERNALLY_GENERATED_IV , NOT_RESYNCHRONIZABLE }
	Secure IVs requirements as enumerated values. More...

Detailed Description

Block cipher mode of operation information.

Definition at line 49 of file modes.h.

Constructor & Destructor Documentation

◆ ~CipherModeBase()

virtual CipherModeBase::~CipherModeBase ( )

inlinevirtual

Definition at line 52 of file modes.h.

Member Function Documentation

◆ AlgorithmProvider()

std::string CipherModeBase::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.

Since: Crypto++ 8.0

Reimplemented from Algorithm.

Reimplemented in XTS_ModeBase.

Definition at line 55 of file modes.h.

◆ MinKeyLength()

size_t CipherModeBase::MinKeyLength ( ) const

inlinevirtual

Returns smallest valid key length.

Returns: the minimum key length, in bytes

Implements SimpleKeyingInterface.

Reimplemented in XTS_ModeBase.

Definition at line 61 of file modes.h.

◆ MaxKeyLength()

size_t CipherModeBase::MaxKeyLength ( ) const

inlinevirtual

Returns largest valid key length.

Returns: the maximum key length, in bytes

Implements SimpleKeyingInterface.

Reimplemented in XTS_ModeBase.

Definition at line 65 of file modes.h.

◆ DefaultKeyLength()

size_t CipherModeBase::DefaultKeyLength ( ) const

inlinevirtual

Returns default key length.

Returns: the default key length, in bytes

Implements SimpleKeyingInterface.

Reimplemented in XTS_ModeBase.

Definition at line 69 of file modes.h.

◆ GetValidKeyLength()

size_t CipherModeBase::GetValidKeyLength ( size_t keylength ) const

inlinevirtual

Returns a valid key length for the algorithm.

Parameters

keylength the size of the key, in bytes

Returns: the valid key length, in bytes

keylength is provided in bytes, not bits. If keylength is less than MIN_KEYLENGTH, then the function returns MIN_KEYLENGTH. If keylength is greater than MAX_KEYLENGTH, then the function returns MAX_KEYLENGTH. if If keylength is a multiple of KEYLENGTH_MULTIPLE, then keylength is returned. Otherwise, the function returns a lower multiple of KEYLENGTH_MULTIPLE.

Implements SimpleKeyingInterface.

Reimplemented in XTS_ModeBase.

Definition at line 79 of file modes.h.

◆ IsValidKeyLength()

bool CipherModeBase::IsValidKeyLength ( size_t keylength ) const

inlinevirtual

Returns whether keylength is a valid key length.

Parameters

keylength the requested keylength

Returns: true if keylength is valid, false otherwise

Internally the function calls GetValidKeyLength()

Reimplemented from SimpleKeyingInterface.

Reimplemented in XTS_ModeBase.

Definition at line 85 of file modes.h.

◆ OptimalDataAlignment()

unsigned int CipherModeBase::OptimalDataAlignment ( ) const

inlinevirtual

Provides input and output data alignment for optimal performance.

Returns: the input data alignment that provides optimal performance

See also: GetAlignment() and OptimalBlockSize()

Reimplemented from StreamTransformation.

Reimplemented in XTS_ModeBase.

Definition at line 90 of file modes.h.

◆ IVSize()

unsigned int CipherModeBase::IVSize ( ) const

inlinevirtual

Returns length of the IV accepted by this object.

Returns: the size of an IV, in bytes

Exceptions

NotImplemented() if the object does not support resynchronization

The default implementation throws NotImplemented

Reimplemented from SimpleKeyingInterface.

Definition at line 96 of file modes.h.

◆ IVRequirement()

virtual IV_Requirement CipherModeBase::IVRequirement ( ) const

pure virtual

Minimal requirement for secure IVs.

Returns: the secure IV requirement of the algorithm

Implements SimpleKeyingInterface.

Implemented in CFB_ModePolicy, OFB_ModePolicy, CTR_ModePolicy, ECB_OneWay, CBC_ModeBase, and XTS_ModeBase.

◆ SetCipher()

void CipherModeBase::SetCipher ( BlockCipher & cipher )

inline

Set external block cipher.

Parameters

cipher An external block cipher

The cipher should be keyed.

Definition at line 105 of file modes.h.

◆ SetCipherWithIV()

void CipherModeBase::SetCipherWithIV	(	BlockCipher &	cipher,
		const byte *	iv,
		int	feedbackSize = 0 )

inline

Set external block cipher and IV.

Parameters

cipher	An external block cipher
iv	a byte array used to resynchronize the cipher
feedbackSize	the feedback size, in bytes

The cipher should be keyed.

Definition at line 117 of file modes.h.

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

modes.h

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ~CipherModeBase()

Member Function Documentation

◆ AlgorithmProvider()

◆ MinKeyLength()

◆ MaxKeyLength()

◆ DefaultKeyLength()

◆ GetValidKeyLength()

◆ IsValidKeyLength()

◆ OptimalDataAlignment()

◆ IVSize()

◆ IVRequirement()

◆ SetCipher()

◆ SetCipherWithIV()