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

Base class for feedback based stream ciphers with SymmetricCipher interface. More...

+ Inheritance diagram for CFB_CipherTemplate< BASE >:

Public Types

typedef BASE::PolicyInterface PolicyInterface
 

Public Member Functions

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 IsRandomAccess () const
 Flag indicating random access. More...
 
bool IsSelfInverting () const
 Determines if the cipher is self inverting. More...
 
std::string AlgorithmProvider () const
 Retrieve the provider of this algorithm. More...
 

Detailed Description

template<class BASE>
class CFB_CipherTemplate< BASE >

Base class for feedback based stream ciphers with SymmetricCipher interface.

Template Parameters
BASEAbstractPolicyHolder base class

Definition at line 562 of file strciphr.h.

Member Function Documentation

◆ ProcessData()

template<class BASE >
void CFB_CipherTemplate< BASE >::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 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);

◆ Resynchronize()

template<class BASE >
void CFB_CipherTemplate< BASE >::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

◆ OptimalBlockSize()

template<class BASE >
unsigned int CFB_CipherTemplate< 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 592 of file strciphr.h.

◆ GetOptimalNextBlockSize()

template<class BASE >
unsigned int CFB_CipherTemplate< 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 598 of file strciphr.h.

◆ OptimalDataAlignment()

template<class BASE >
unsigned int CFB_CipherTemplate< 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 603 of file strciphr.h.

◆ IsRandomAccess()

template<class BASE >
bool CFB_CipherTemplate< BASE >::IsRandomAccess ( ) const
inline

Flag indicating random access.

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

Definition at line 608 of file strciphr.h.

◆ IsSelfInverting()

template<class BASE >
bool CFB_CipherTemplate< 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 612 of file strciphr.h.

◆ AlgorithmProvider()

template<class BASE >
std::string CFB_CipherTemplate< BASE >::AlgorithmProvider ( ) const
inline

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.

Definition at line 628 of file strciphr.h.


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