Crypto++  8.5
Free C++ class library of cryptographic schemes
Public Types | Public Member Functions | List of all members
AdditiveCipherTemplate< BASE > Class Template Reference

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

+ Inheritance diagram for AdditiveCipherTemplate< BASE >:

Public Types

typedef BASE::PolicyInterface PolicyInterface
 
- Public Types inherited from AbstractPolicyHolder< AdditiveCipherAbstractPolicy, SymmetricCipher >
typedef AdditiveCipherAbstractPolicy PolicyInterface
 
- 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...
 

Public Member Functions

void GenerateBlock (byte *output, size_t size)
 Generate random array of bytes. More...
 
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 IsSelfInverting () const
 Determines if the cipher is self inverting. More...
 
bool IsForwardTransformation () const
 Determines if the cipher is a forward transformation. More...
 
bool IsRandomAccess () const
 Flag indicating random access. More...
 
void Seek (lword position)
 Seeks to a random position in the stream. More...
 
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 GetNextIV (RandomNumberGenerator &rng, byte *iv)
 Retrieves a secure IV for the next message. 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 GetOptimalBlockSizeUsed () const
 Provides the number of bytes used in the current block when processing at optimal block size. 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...
 
- 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...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. More...
 
- Public Member Functions inherited from RandomNumberGenerator
virtual void IncorporateEntropy (const byte *input, size_t length)
 Update RNG state with additional unpredictable values. More...
 
virtual bool CanIncorporateEntropy () const
 Determines if a generator can accept additional entropy. More...
 
virtual byte GenerateByte ()
 Generate new random byte and return it. More...
 
virtual unsigned int GenerateBit ()
 Generate new random bit and return it. More...
 
virtual word32 GenerateWord32 (word32 min=0, word32 max=0xffffffffUL)
 Generate a random 32 bit word in the range min to max, inclusive. More...
 
virtual void GenerateIntoBufferedTransformation (BufferedTransformation &target, const std::string &channel, lword length)
 Generate random bytes into a BufferedTransformation. More...
 
virtual void DiscardBytes (size_t n)
 Generate and discard n bytes. More...
 
template<class IT >
void Shuffle (IT begin, IT end)
 Randomly shuffle the specified array. More...
 

Detailed Description

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

Base class for additive stream ciphers with SymmetricCipher interface.

Template Parameters
BASEAbstractPolicyHolder base class

Definition at line 297 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
outputthe byte buffer
sizethe 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 
)
virtual

Apply keystream to data.

Parameters
outStringa buffer to write the transformed data
inStringa buffer to read the data
lengththe 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);

Implements StreamTransformation.

◆ Resynchronize()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
void AdditiveCipherTemplate< BASE >::Resynchronize ( const byte iv,
int  length = -1 
)
virtual

Resynchronize the cipher.

Parameters
iva byte array used to resynchronize the cipher
lengththe size of the IV array

Reimplemented from SimpleKeyingInterface.

◆ OptimalBlockSize()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
unsigned int AdditiveCipherTemplate< BASE >::OptimalBlockSize ( ) const
inlinevirtual

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()

Reimplemented from StreamTransformation.

Definition at line 334 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 340 of file strciphr.h.

◆ OptimalDataAlignment()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
unsigned int AdditiveCipherTemplate< BASE >::OptimalDataAlignment ( ) const
inlinevirtual

Provides number of ideal data alignment.

Returns
the ideal data alignment, in bytes
See also
GetAlignment() and OptimalBlockSize()

Reimplemented from StreamTransformation.

Definition at line 345 of file strciphr.h.

◆ IsSelfInverting()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
bool AdditiveCipherTemplate< BASE >::IsSelfInverting ( ) const
inlinevirtual

Determines if the cipher is self inverting.

Returns
true if the stream cipher is self inverting, false otherwise

Implements StreamTransformation.

Definition at line 349 of file strciphr.h.

◆ IsForwardTransformation()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
bool AdditiveCipherTemplate< BASE >::IsForwardTransformation ( ) const
inlinevirtual

Determines if the cipher is a forward transformation.

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

Implements StreamTransformation.

Definition at line 353 of file strciphr.h.

◆ IsRandomAccess()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
bool AdditiveCipherTemplate< BASE >::IsRandomAccess ( ) const
inlinevirtual

Flag indicating random access.

Returns
true if the cipher is seekable, false otherwise
See also
Seek()

Implements StreamTransformation.

Definition at line 358 of file strciphr.h.

◆ Seek()

template<class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>>
void AdditiveCipherTemplate< BASE >::Seek ( lword  position)
virtual

Seeks to a random position in the stream.

Parameters
positionthe absolute position in the stream
See also
IsRandomAccess()

Reimplemented from StreamTransformation.

◆ 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 379 of file strciphr.h.


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