Crypto++ 8.7
Free C++ class library of cryptographic schemes
Public Member Functions | List of all members
AuthenticatedSymmetricCipherBase Class Referenceabstract

Base class for authenticated encryption modes of operation. More...

#include <authenc.h>

+ Inheritance diagram for AuthenticatedSymmetricCipherBase:

Public Member Functions

bool IsRandomAccess () const
 Determines whether the cipher supports random access. More...
 
bool IsSelfInverting () const
 Determines whether the cipher is self-inverting. More...
 
void SetKey (const byte *userKey, size_t keylength, const NameValuePairs &params)
 Sets or reset the key of this object. More...
 
void Restart ()
 Restart the hash. More...
 
void Resynchronize (const byte *iv, int length=-1)
 Resynchronize with an IV. More...
 
void Update (const byte *input, size_t length)
 Updates a hash with additional input. More...
 
void ProcessData (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt an array of bytes. More...
 
void TruncatedFinal (byte *mac, size_t macSize)
 Computes the hash of the current message. More...
 
- Public Member Functions inherited from AuthenticatedSymmetricCipher
virtual lword MaxHeaderLength () const =0
 Provides the maximum length of AAD that can be input. More...
 
virtual lword MaxMessageLength () const =0
 Provides the maximum length of encrypted data. More...
 
virtual lword MaxFooterLength () const
 Provides the maximum length of AAD. More...
 
virtual bool NeedsPrespecifiedDataLengths () const
 Determines if data lengths must be specified prior to inputting data. More...
 
void SpecifyDataLengths (lword headerLength, lword messageLength, lword footerLength=0)
 Prescribes the data lengths. More...
 
virtual void EncryptAndAuthenticate (byte *ciphertext, byte *mac, size_t macSize, const byte *iv, int ivLength, const byte *header, size_t headerLength, const byte *message, size_t messageLength)
 Encrypts and calculates a MAC in one call. More...
 
virtual bool DecryptAndVerify (byte *message, const byte *mac, size_t macSize, const byte *iv, int ivLength, const byte *header, size_t headerLength, const byte *ciphertext, size_t ciphertextLength)
 Decrypts and verifies a MAC in one call. More...
 
virtual std::string AlgorithmName () const
 Provides the name of this algorithm. More...
 
virtual std::string AlgorithmProvider () const
 Retrieve the provider of this algorithm. More...
 
- Public Member Functions inherited from SimpleKeyingInterface
virtual size_t MinKeyLength () const =0
 Returns smallest valid key length. More...
 
virtual size_t MaxKeyLength () const =0
 Returns largest valid key length. More...
 
virtual size_t DefaultKeyLength () const =0
 Returns default key length. More...
 
virtual size_t GetValidKeyLength (size_t keylength) const =0
 Returns a valid key length for the algorithm. More...
 
virtual bool IsValidKeyLength (size_t keylength) const
 Returns whether keylength is a valid key length. More...
 
virtual void SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
 Sets or reset the key of this object. More...
 
void SetKeyWithRounds (const byte *key, size_t length, int rounds)
 Sets or reset the key of this object. More...
 
void SetKeyWithIV (const byte *key, size_t length, const byte *iv, size_t ivLength)
 Sets or reset the key of this object. More...
 
void SetKeyWithIV (const byte *key, size_t length, const byte *iv)
 Sets or reset the key of this object. More...
 
virtual IV_Requirement IVRequirement () const =0
 Minimal requirement for secure IVs. More...
 
bool IsResynchronizable () const
 Determines if the object can be resynchronized. More...
 
bool CanUseRandomIVs () const
 Determines if the object can use random IVs. More...
 
bool CanUsePredictableIVs () const
 Determines if the object can use random but possibly predictable IVs. More...
 
bool CanUseStructuredIVs () const
 Determines if the object can use structured IVs. More...
 
virtual unsigned int IVSize () const
 Returns length of the IV accepted by this object. More...
 
unsigned int DefaultIVLength () const
 Provides the default size of an IV. More...
 
virtual unsigned int MinIVLength () const
 Provides the minimum size of an IV. More...
 
virtual unsigned int MaxIVLength () const
 Provides the maximum size of an IV. More...
 
virtual void Resynchronize (const byte *iv, int ivLength=-1)
 Resynchronize with an IV. More...
 
virtual void GetNextIV (RandomNumberGenerator &rng, byte *iv)
 Retrieves a secure IV for the next message. More...
 
- Public Member Functions inherited from HashTransformation
HashTransformationRef ()
 Provides a reference to this object. More...
 
virtual void Update (const byte *input, size_t length)=0
 Updates a hash with additional input. More...
 
virtual byteCreateUpdateSpace (size_t &size)
 Request space which can be written into by the caller. More...
 
virtual void Final (byte *digest)
 Computes the hash of the current message. More...
 
virtual void Restart ()
 Restart the hash. More...
 
virtual unsigned int DigestSize () const =0
 Provides the digest size of the hash. More...
 
unsigned int TagSize () const
 Provides the tag size of the hash. More...
 
virtual unsigned int BlockSize () const
 Provides the block size of the compression function. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this hash. More...
 
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance. More...
 
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. More...
 
virtual bool Verify (const byte *digest)
 Verifies the hash of the current message. More...
 
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. More...
 
virtual void TruncatedFinal (byte *digest, size_t digestSize)=0
 Computes the hash of the current message. More...
 
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. More...
 
virtual bool TruncatedVerify (const byte *digest, size_t digestLength)
 Verifies the hash of the current message. More...
 
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. 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...
 
virtual std::string AlgorithmProvider () const
 Retrieve the provider of this algorithm. More...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. More...
 
- Public Member Functions inherited from StreamTransformation
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 size_t ProcessLastBlock (byte *outString, size_t outLength, const byte *inString, size_t inLength)
 Encrypt or decrypt the last block of data. More...
 
virtual unsigned int MinLastBlockSize () const
 Provides the size of the last block. More...
 
virtual bool IsLastBlockSpecial () const
 Determines if the last block receives special processing. 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...
 

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

Base class for authenticated encryption modes of operation.

AuthenticatedSymmetricCipherBase() serves as a base implementation for one direction (encryption or decryption) of a stream cipher or block cipher mode with authentication.

Crypto++ provides four authenticated encryption modes of operation - CCM, EAX, GCM and OCB mode. All modes derive from AuthenticatedSymmetricCipherBase() and the motivation for the API, like calling AAD a "header", can be found in Bellare, Rogaway and Wagner's The EAX Mode of Operation. The EAX paper suggested a basic API to help standardize AEAD schemes in software and promote adoption of the modes.

See also
Authenticated Encryption on the Crypto++ wiki.
Since
Crypto++ 5.6.0

Definition at line 40 of file authenc.h.

Constructor & Destructor Documentation

◆ AuthenticatedSymmetricCipherBase()

AuthenticatedSymmetricCipherBase::AuthenticatedSymmetricCipherBase ( )
inline

Definition at line 43 of file authenc.h.

Member Function Documentation

◆ IsRandomAccess()

bool AuthenticatedSymmetricCipherBase::IsRandomAccess ( ) const
inlinevirtual

Determines whether the cipher supports random access.

Returns
true if the cipher supports random access, false otherwise

Implements StreamTransformation.

Definition at line 47 of file authenc.h.

◆ IsSelfInverting()

bool AuthenticatedSymmetricCipherBase::IsSelfInverting ( ) const
inlinevirtual

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).

Implements StreamTransformation.

Definition at line 48 of file authenc.h.

◆ SetKey()

void AuthenticatedSymmetricCipherBase::SetKey ( const byte key,
size_t  length,
const NameValuePairs params 
)
virtual

Sets or reset the key of this object.

Parameters
keythe key to use when keying the object
lengththe size of the key, in bytes
paramsadditional initialization parameters to configure this object

Reimplemented from SimpleKeyingInterface.

◆ Restart()

void AuthenticatedSymmetricCipherBase::Restart ( )
inlinevirtual

Restart the hash.

Discards the current state, and restart for a new message

Reimplemented from HashTransformation.

Definition at line 51 of file authenc.h.

◆ Resynchronize()

void AuthenticatedSymmetricCipherBase::Resynchronize ( const byte iv,
int  ivLength = -1 
)
virtual

Resynchronize with an IV.

Parameters
ivthe initialization vector
ivLengththe size of the initialization vector, in bytes

Resynchronize() resynchronizes with an IV provided by the caller. ivLength=-1 means use IVSize().

Exceptions
NotImplemented()if the object does not support resynchronization

Reimplemented from SimpleKeyingInterface.

◆ Update()

void AuthenticatedSymmetricCipherBase::Update ( const byte input,
size_t  length 
)
virtual

Updates a hash with additional input.

Parameters
inputthe additional input as a buffer
lengththe size of the buffer, in bytes

Implements HashTransformation.

◆ ProcessData()

void AuthenticatedSymmetricCipherBase::ProcessData ( byte outString,
const byte inString,
size_t  length 
)
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

ProcessData is called with a string of bytes whose size depends on MandatoryBlockSize. Either inString == outString, or they must not overlap.

See also
ProcessData, ProcessLastBlock, MandatoryBlockSize, MinLastBlockSize, BlockPaddingSchemeDef, IsLastBlockSpecial

Implements StreamTransformation.

◆ TruncatedFinal()

void AuthenticatedSymmetricCipherBase::TruncatedFinal ( byte digest,
size_t  digestSize 
)
virtual

Computes the hash of the current message.

Parameters
digesta pointer to the buffer to receive the hash
digestSizethe size of the truncated digest, in bytes

TruncatedFinal() calls Final() and then copies digestSize bytes to digest. The hash is restarted the hash for the next message.

Precondition
COUNTOF(digest) <= DigestSize() or COUNTOF(digest) <= HASH::DIGESTSIZE ensures the output byte buffer is a valid size.

Implements HashTransformation.


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