Crypto++  5.6.3
Free C++ class library of cryptographic schemes
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

std::string AlgorithmName () const
 Provides the name of this algorithm. More...
 
 RDRAND (unsigned int retries=8)
 Construct a RDRAND generator. More...
 
unsigned int GetRetries () const
 Retrieve the number of retries used by the generator. More...
 
void SetRetries (unsigned int retries)
 Set the number of retries used by the 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...
 
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...
 
virtual ClonableClone () const
 Copies this object. More...
 

Detailed Description

Hardware generated random numbers using RDRAND instruction.

See also
MaurerRandomnessTest() for random bit generators

Definition at line 37 of file rdrand.h.

Constructor & Destructor Documentation

RDRAND::RDRAND ( unsigned int  retries = 8)
inline

Construct a RDRAND generator.

Parameters
retriesthe number of retries for failed calls to the hardware

RDRAND() constructs a generator with a maximum number of retires for failed generation attempts.

Definition at line 46 of file rdrand.h.

Member Function Documentation

std::string RDRAND::AlgorithmName ( ) const
inlinevirtual

Provides the name of this algorithm.

Returns
the standard algorithm name

The standard algorithm name can be a name like AES or AES/GCM. Some algorithms do not have standard names yet. For example, there is no standard algorithm name for Shoup's ECIES.

Note
AlgorithmName is not universally implemented yet

Reimplemented from Algorithm.

Definition at line 40 of file rdrand.h.

unsigned int RDRAND::GetRetries ( ) const
inline

Retrieve the number of retries used by the generator.

Returns
the number of times GenerateBlock() will attempt to recover from a failed generation

Definition at line 52 of file rdrand.h.

void RDRAND::SetRetries ( unsigned int  retries)
inline

Set the number of retries used by the generator.

Parameters
retriesnumber of times GenerateBlock() will attempt to recover from a failed generation

Definition at line 59 of file rdrand.h.

References GenerateBlock().

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

Generate random array of bytes.

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

Reimplemented from RandomNumberGenerator.

Definition at line 70 of file rdrand.h.

References DiscardBytes().

Referenced by SetRetries(), and RDSEED::SetRetries().

virtual void RDRAND::DiscardBytes ( size_t  n)
inlinevirtual

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 84 of file rdrand.h.

Referenced by GenerateBlock(), and RDSEED::GenerateBlock().

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 94 of file rdrand.h.

virtual bool RandomNumberGenerator::CanIncorporateEntropy ( ) const
inlinevirtualinherited

Determines if a generator can accept additional entropy.

Returns
true if IncorporateEntropy() is implemented

Reimplemented in ClassNullRNG, AutoSeededX917RNG< BLOCK_CIPHER >, and RandomPool.

Definition at line 1104 of file cryptlib.h.

Referenced by DL_SignerBase< SCHEME_OPTIONS::Element >::SignAndRestart().

byte RandomNumberGenerator::GenerateByte ( )
virtualinherited

Generate new random byte and return it.

Returns
a random 8-bit byte

Default implementation calls GenerateBlock() with one byte.

All generated values are uniformly distributed over the range specified within the the contraints of a particular generator.

Reimplemented in ClassNullRNG, and PublicBlumBlumShub.

Definition at line 294 of file cryptlib.cpp.

unsigned int RandomNumberGenerator::GenerateBit ( )
virtualinherited

Generate new random bit and return it.

Returns
a random bit

The default implementation calls GenerateByte() and return its lowest bit.

All generated values are uniformly distributed over the range specified within the the contraints of a particular generator.

Reimplemented in ClassNullRNG, and PublicBlumBlumShub.

Definition at line 289 of file cryptlib.cpp.

Referenced by TestDataNameValuePairs::GetVoidValue().

word32 RandomNumberGenerator::GenerateWord32 ( word32  min = 0,
word32  max = 0xffffffffUL 
)
virtualinherited

Generate a random 32 bit word in the range min to max, inclusive.

Parameters
minthe lower bound of the range
maxthe upper bound of the range
Returns
a random 32-bit word

The default implementation calls Crop() on the difference between max and min, and then returns the result added to min.

All generated values are uniformly distributed over the range specified within the the contraints of a particular generator.

Reimplemented in ClassNullRNG, and MersenneTwister< K, M, N, F, S >.

Definition at line 301 of file cryptlib.cpp.

References BitPrecision(), and Crop().

Referenced by MaurerProvablePrime(), PKCS_EncryptionPaddingScheme::MaxUnpaddedLength(), MihailescuProvablePrime(), and FilterTester::Put2().

void RandomNumberGenerator::GenerateIntoBufferedTransformation ( BufferedTransformation target,
const std::string &  channel,
lword  length 
)
virtualinherited

Generate random bytes into a BufferedTransformation.

Parameters
targetthe BufferedTransformation object which receives the bytes
channelthe channel on which the bytes should be pumped
lengththe number of bytes to generate

The default implementation calls GenerateBlock() and pumps the result into the DEFAULT_CHANNEL of the target.

All generated values are uniformly distributed over the range specified within the the contraints of a particular generator.

Note
A derived generator must override either GenerateBlock() or GenerateIntoBufferedTransformation(). They can override both, or have one call the other.

Reimplemented in ClassNullRNG, AutoSeededX917RNG< BLOCK_CIPHER >, X917RNG, and RandomPool.

Definition at line 347 of file cryptlib.cpp.

References BufferedTransformation::ChannelPut(), SecBlock< T, A >::size(), and UnsignedMin().

template<class IT >
void RandomNumberGenerator::Shuffle ( IT  begin,
IT  end 
)
inlineinherited

Randomly shuffle the specified array.

Parameters
beginan iterator to the first element in the array
endan iterator beyond the last element in the array

The resulting permutation is uniformly distributed.

Definition at line 1159 of file cryptlib.h.

References GetByte(), and NullRNG().

virtual Clonable* Clonable::Clone ( ) const
inlinevirtualinherited

Copies this object.

Returns
a copy of this object
Exceptions
NotImplemented
Note
this is not implemented by most classes
See also
NotCopyable

Definition at line 464 of file cryptlib.h.


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