Crypto++  5.6.5
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 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...
 
- 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...
 
- 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...
 

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 267 of file strciphr.h.

Member Function Documentation

template<class S >
void AdditiveCipherTemplate< S >::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 the contraints of a particular generator.

Reimplemented from RandomNumberGenerator.

Definition at line 29 of file strciphr.cpp.

template<class S >
void AdditiveCipherTemplate< S >::ProcessData ( byte *  outString,
const byte *  inString,
size_t  length 
)

Apply keystream to data.

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

Definition at line 67 of file strciphr.cpp.

template<class S >
void AdditiveCipherTemplate< S >::Resynchronize ( const byte *  iv,
int  length = -1 
)

Resynchronize the cipher.

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

Definition at line 126 of file strciphr.cpp.

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 303 of file strciphr.h.

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 309 of file strciphr.h.

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 314 of file strciphr.h.

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 318 of file strciphr.h.

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 322 of file strciphr.h.

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 327 of file strciphr.h.

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

Seeks to a random position in the stream.

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

Definition at line 135 of file strciphr.cpp.


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