Crypto++  5.6.5
Free C++ class library of cryptographic schemes
Public Member Functions | Static Public Member Functions | List of all members
RDRAND Class Reference

Hardware generated random numbers using RDRAND instruction. More...

+ Inheritance diagram for RDRAND:

Public Member Functions

 RDRAND ()
 Construct a RDRAND generator. More...
 
virtual void GenerateBlock (byte *output, size_t size)
 Generate random array of bytes. More...
 
virtual void DiscardBytes (size_t n)
 Generate and discard n bytes. More...
 
virtual void IncorporateEntropy (const byte *input, size_t length)
 Update RNG state with additional unpredictable values. More...
 
- Public Member Functions inherited from RandomNumberGenerator
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...
 
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...
 

Static Public Member Functions

static const char * StaticAlgorithmName ()
 

Detailed Description

Hardware generated random numbers using RDRAND instruction.

See also
MaurerRandomnessTest() for random bit generators
Since
Crypto++ 5.6.3

Definition at line 49 of file rdrand.h.

Constructor & Destructor Documentation

◆ RDRAND()

RDRAND::RDRAND ( )
inline

Construct a RDRAND generator.

According to DJ of Intel, the Intel RDRAND circuit does not underflow. If it did hypothetically underflow, then it would return 0 for the random value. AMD's RDRAND implementation appears to provide the same behavior except the values are not generated consistent with FIPS 140.

Definition at line 61 of file rdrand.h.

Member Function Documentation

◆ GenerateBlock()

void RDRAND::GenerateBlock ( byte *  output,
size_t  size 
)
virtual

Generate random array of bytes.

Parameters
outputthe byte buffer
sizethe length of the buffer, in bytes

Reimplemented from RandomNumberGenerator.

Definition at line 203 of file rdrand.cpp.

◆ DiscardBytes()

void RDRAND::DiscardBytes ( size_t  n)
virtual

Generate and discard n bytes.

Parameters
nthe number of bytes to generate and discard

the RDSEED generator discards words, not bytes. If n is not a multiple of a machine word, then it is rounded up to that size.

Reimplemented from RandomNumberGenerator.

Definition at line 250 of file rdrand.cpp.

◆ IncorporateEntropy()

virtual void RDRAND::IncorporateEntropy ( const byte *  input,
size_t  length 
)
inlinevirtual

Update RNG state with additional unpredictable values.

Parameters
inputunused
lengthunused

The operation is a nop for this generator.

Reimplemented from RandomNumberGenerator.

Definition at line 79 of file rdrand.h.


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