IETF XChaCha20Poly1305 cipher base implementation. More...

#include <chachapoly.h>

Inheritance diagram for XChaCha20Poly1305_Base:

Public Member Functions
std::string	AlgorithmName () const
	Provides the name of this algorithm.

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 n) const
	Returns a valid key length for the algorithm.

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

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

IV_Requirement	IVRequirement () const
	Minimal requirement for secure IVs.

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

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

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

unsigned int	DigestSize () const
	Provides the digest size of the hash.

lword	MaxHeaderLength () const
	Provides the maximum length of AAD that can be input.

lword	MaxMessageLength () const
	Provides the maximum length of encrypted data.

lword	MaxFooterLength () const
	Provides the maximum length of AAD.

virtual void	EncryptAndAuthenticate (byte ciphertext, byte mac, size_t macSize, const byte iv, int ivLength, const byte aad, size_t aadLength, const byte *message, size_t messageLength)
	Encrypts and calculates a MAC in one call.

virtual bool	DecryptAndVerify (byte message, const byte mac, size_t macSize, const byte iv, int ivLength, const byte aad, size_t aadLength, const byte *ciphertext, size_t ciphertextLength)
	Decrypts and verifies a MAC in one call.

Public Member Functions inherited from AuthenticatedSymmetricCipherBase
bool	IsRandomAccess () const
	Determines whether the cipher supports random access.

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

void	SetKey (const byte *userKey, size_t keylength, const NameValuePairs &params)
	Sets or reset the key of this object.

void	Restart ()
	Restart the hash.

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

void	Update (const byte *input, size_t length)
	Updates a hash with additional input.

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

void	TruncatedFinal (byte *mac, size_t macSize)
	Computes the hash of the current message.

Public Member Functions inherited from AuthenticatedSymmetricCipher
virtual bool	NeedsPrespecifiedDataLengths () const
	Determines if data lengths must be specified prior to inputting data.

void	SpecifyDataLengths (lword headerLength, lword messageLength, lword footerLength=0)
	Prescribes the data lengths.

Public Member Functions inherited from SimpleKeyingInterface
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 void	GetNextIV (RandomNumberGenerator &rng, byte *iv)
	Retrieves a secure IV for the next message.

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

virtual byte *	CreateUpdateSpace (size_t &size)
	Request space which can be written into by the caller.

virtual void	Final (byte *digest)
	Computes the hash of the current message.

unsigned int	TagSize () const
	Provides the tag size of the hash.

virtual unsigned int	BlockSize () const
	Provides the block size of the compression function.

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

virtual void	CalculateDigest (byte digest, const byte input, size_t length)
	Updates the hash with additional input and computes the hash of the current message.

virtual bool	Verify (const byte *digest)
	Verifies the hash of the current message.

virtual bool	VerifyDigest (const byte digest, const byte input, size_t length)
	Updates the hash with additional input and verifies the hash of the current message.

virtual void	CalculateTruncatedDigest (byte digest, size_t digestSize, const byte input, size_t length)
	Updates the hash with additional input and computes the hash of the current message.

virtual bool	TruncatedVerify (const byte *digest, size_t digestLength)
	Verifies the hash of the current message.

virtual bool	VerifyTruncatedDigest (const byte digest, size_t digestLength, const byte input, size_t length)
	Updates the hash with additional input and verifies the hash of the current message.

Public Member Functions inherited from Algorithm
	Algorithm (bool checkSelfTestStatus=true)
	Interface for all crypto algorithms.

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

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

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

Static Public Member Functions
static const char *	StaticAlgorithmName ()

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

IETF XChaCha20Poly1305 cipher base implementation.

Base implementation of the AuthenticatedSymmetricCipher interface

Since: Crypto++ 8.1

Definition at line 177 of file chachapoly.h.

Constructor & Destructor Documentation

◆ ~XChaCha20Poly1305_Base()

virtual XChaCha20Poly1305_Base::~XChaCha20Poly1305_Base ( )

inlinevirtual

Definition at line 183 of file chachapoly.h.

Member Function Documentation

◆ StaticAlgorithmName()

static const char * XChaCha20Poly1305_Base::StaticAlgorithmName ( )

inlinestatic

Definition at line 180 of file chachapoly.h.

◆ AlgorithmName()

std::string XChaCha20Poly1305_Base::AlgorithmName ( ) const

inlinevirtual

Provides the name of this algorithm.

Returns: the standard algorithm name

The standard algorithm name can be a name like AES or AES/GCM. Some algorithms do not have standard names yet. For example, there is no standard algorithm name for Shoup's ECIES.

Reimplemented from AuthenticatedSymmetricCipher.

Definition at line 186 of file chachapoly.h.

◆ AlgorithmProvider()

std::string XChaCha20Poly1305_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.

Since: Crypto++ 8.0

Reimplemented from AuthenticatedSymmetricCipher.

Definition at line 188 of file chachapoly.h.

◆ MinKeyLength()

size_t XChaCha20Poly1305_Base::MinKeyLength ( ) const

inlinevirtual

Returns smallest valid key length.

Returns: the minimum key length, in bytes

Implements SimpleKeyingInterface.

Definition at line 190 of file chachapoly.h.

◆ MaxKeyLength()

size_t XChaCha20Poly1305_Base::MaxKeyLength ( ) const

inlinevirtual

Returns largest valid key length.

Returns: the maximum key length, in bytes

Implements SimpleKeyingInterface.

Definition at line 192 of file chachapoly.h.

◆ DefaultKeyLength()

size_t XChaCha20Poly1305_Base::DefaultKeyLength ( ) const

inlinevirtual

Returns default key length.

Returns: the default key length, in bytes

Implements SimpleKeyingInterface.

Definition at line 194 of file chachapoly.h.

◆ GetValidKeyLength()

size_t XChaCha20Poly1305_Base::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.

Definition at line 196 of file chachapoly.h.

◆ IsValidKeyLength()

bool XChaCha20Poly1305_Base::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.

Definition at line 198 of file chachapoly.h.

◆ OptimalDataAlignment()

unsigned int XChaCha20Poly1305_Base::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 HashTransformation.

Definition at line 200 of file chachapoly.h.

◆ IVRequirement()

IV_Requirement XChaCha20Poly1305_Base::IVRequirement ( ) const

inlinevirtual

Minimal requirement for secure IVs.

Returns: the secure IV requirement of the algorithm

Implements SimpleKeyingInterface.

Definition at line 202 of file chachapoly.h.

◆ IVSize()

unsigned int XChaCha20Poly1305_Base::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 204 of file chachapoly.h.

◆ MinIVLength()

unsigned int XChaCha20Poly1305_Base::MinIVLength ( ) const

inlinevirtual

Provides the minimum size of an IV.

Returns: minimal length of IVs accepted by this object, in bytes

Exceptions

NotImplemented() if the object does not support resynchronization

Reimplemented from SimpleKeyingInterface.

Definition at line 206 of file chachapoly.h.

◆ MaxIVLength()

unsigned int XChaCha20Poly1305_Base::MaxIVLength ( ) const

inlinevirtual

Provides the maximum size of an IV.

Returns: maximal length of IVs accepted by this object, in bytes

Exceptions

NotImplemented() if the object does not support resynchronization

Reimplemented from SimpleKeyingInterface.

Definition at line 208 of file chachapoly.h.

◆ DigestSize()

unsigned int XChaCha20Poly1305_Base::DigestSize ( ) const

inlinevirtual

Provides the digest size of the hash.

Returns: the digest size of the hash.

Implements HashTransformation.

Definition at line 210 of file chachapoly.h.

◆ MaxHeaderLength()

lword XChaCha20Poly1305_Base::MaxHeaderLength ( ) const

inlinevirtual

Provides the maximum length of AAD that can be input.

Returns: the maximum length of AAD that can be input before the encrypted data

Implements AuthenticatedSymmetricCipher.

Definition at line 212 of file chachapoly.h.

◆ MaxMessageLength()

lword XChaCha20Poly1305_Base::MaxMessageLength ( ) const

inlinevirtual

Provides the maximum length of encrypted data.

Returns: the maximum length of encrypted data

Implements AuthenticatedSymmetricCipher.

Definition at line 214 of file chachapoly.h.

◆ MaxFooterLength()

lword XChaCha20Poly1305_Base::MaxFooterLength ( ) const

inlinevirtual

Provides the maximum length of AAD.

Returns: the maximum length of AAD that can be input after the encrypted data

Reimplemented from AuthenticatedSymmetricCipher.

Definition at line 216 of file chachapoly.h.

◆ EncryptAndAuthenticate()

void XChaCha20Poly1305_Base::EncryptAndAuthenticate	(	byte *	ciphertext,
		byte *	mac,
		size_t	macSize,
		const byte *	iv,
		int	ivLength,
		const byte *	aad,
		size_t	aadLength,
		const byte *	message,
		size_t	messageLength )

virtual

Encrypts and calculates a MAC in one call.

Parameters

ciphertext	the encryption buffer
mac	the mac buffer
macSize	the size of the MAC buffer, in bytes
iv	the iv buffer
ivLength	the size of the IV buffer, in bytes
aad	the AAD buffer
aadLength	the size of the AAD buffer, in bytes
message	the message buffer
messageLength	the size of the messagetext buffer, in bytes

EncryptAndAuthenticate() encrypts and generates the MAC in one call. The function truncates the MAC if macSize < TagSize().

Reimplemented from AuthenticatedSymmetricCipher.

Definition at line 195 of file chachapoly.cpp.

◆ DecryptAndVerify()

bool XChaCha20Poly1305_Base::DecryptAndVerify	(	byte *	message,
		const byte *	mac,
		size_t	macSize,
		const byte *	iv,
		int	ivLength,
		const byte *	aad,
		size_t	aadLength,
		const byte *	ciphertext,
		size_t	ciphertextLength )

virtual

Decrypts and verifies a MAC in one call.

Parameters

message	the decryption buffer
mac	the mac buffer
macSize	the size of the MAC buffer, in bytes
iv	the iv buffer
ivLength	the size of the IV buffer, in bytes
aad	the AAD buffer
aadLength	the size of the AAD buffer, in bytes
ciphertext	the cipher buffer
ciphertextLength	the size of the ciphertext buffer, in bytes

Returns: true if the MAC is valid and the decoding succeeded, false otherwise

DecryptAndVerify() decrypts and verifies the MAC in one call. message is a decryption buffer and should be at least as large as the ciphertext buffer.

The function returns true iff MAC is valid. DecryptAndVerify() assumes the MAC is truncated if macLength < TagSize().

Reimplemented from AuthenticatedSymmetricCipher.

Definition at line 203 of file chachapoly.cpp.

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

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ~XChaCha20Poly1305_Base()

Member Function Documentation

◆ StaticAlgorithmName()

◆ AlgorithmName()

◆ AlgorithmProvider()

◆ MinKeyLength()

◆ MaxKeyLength()

◆ DefaultKeyLength()

◆ GetValidKeyLength()

◆ IsValidKeyLength()

◆ OptimalDataAlignment()

◆ IVRequirement()

◆ IVSize()

◆ MinIVLength()

◆ MaxIVLength()

◆ DigestSize()

◆ MaxHeaderLength()

◆ MaxMessageLength()

◆ MaxFooterLength()

◆ EncryptAndAuthenticate()

◆ DecryptAndVerify()