Botan::Entropy_Source Class Reference

#include <entropy_src.h>

Inheritance diagram for Botan::Entropy_Source:

Public Member Functions
	Entropy_Source ()=default
	Entropy_Source (const Entropy_Source &other)=delete
	Entropy_Source (Entropy_Source &&other)=delete
virtual std::string	name () const =0
Entropy_Source &	operator= (const Entropy_Source &other)=delete
Entropy_Source &	operator= (Entropy_Source &&other)=delete
virtual size_t	poll (RandomNumberGenerator &rng)=0
virtual	~Entropy_Source ()=default

Static Public Member Functions
static std::unique_ptr< Entropy_Source >	create (std::string_view type)

Detailed Description

Abstract interface to a source of entropy

Definition at line 25 of file entropy_src.h.

Constructor & Destructor Documentation

Entropy_Source() [1/3]

Botan::Entropy_Source::Entropy_Source ( )

default

Default constructor

Referenced by Entropy_Source(), Entropy_Source(), operator=(), and operator=().

Entropy_Source() [2/3]

Botan::Entropy_Source::Entropy_Source ( const Entropy_Source & other )

delete

References Entropy_Source().

Entropy_Source() [3/3]

Botan::Entropy_Source::Entropy_Source ( Entropy_Source && other )

delete

References Entropy_Source().

~Entropy_Source()

virtual Botan::Entropy_Source::~Entropy_Source ( )

virtualdefault

Member Function Documentation

create()

std::unique_ptr< Entropy_Source > Botan::Entropy_Source::create ( std::string_view type )

static

Return a new entropy source of a particular type, or null Each entropy source may require substantial resources (eg, a file handle or socket instance), so try to share them among multiple RNGs, or just use the preconfigured global list accessed by Entropy_Sources::global_sources()

Definition at line 111 of file entropy_srcs.cpp.

                                                                        {
#if defined(BOTAN_HAS_SYSTEM_RNG)
   if(name == "system_rng") {
      return std::make_unique<System_RNG_EntropySource>();
   }
#endif
 
#if defined(BOTAN_HAS_PROCESSOR_RNG)
   if(name == "hwrng") {
      if(Processor_RNG::available()) {
         return std::make_unique<Processor_RNG_EntropySource>();
      }
   }
#endif
 
#if defined(BOTAN_HAS_ENTROPY_SRC_RDSEED)
   if(name == "rdseed") {
      return std::make_unique<Intel_Rdseed>();
   }
#endif
 
#if defined(BOTAN_HAS_ENTROPY_SRC_GETENTROPY)
   if(name == "getentropy") {
      return std::make_unique<Getentropy>();
   }
#endif
 
#if defined(BOTAN_HAS_ENTROPY_SRC_WIN32)
   if(name == "system_stats") {
      return std::make_unique<Win32_EntropySource>();
   }
#endif
 
#if defined(BOTAN_HAS_JITTER_RNG)
   if(name == "jitter_rng") {
      return std::make_unique<Jitter_RNG_EntropySource>();
   }
#endif
 
   BOTAN_UNUSED(name);
   return nullptr;
}

References Botan::Processor_RNG::available(), BOTAN_UNUSED, and name().

Referenced by Botan::Entropy_Sources::Entropy_Sources().

name()

virtual std::string Botan::Entropy_Source::name ( ) const

pure virtual

Return a free-form string identifying this entropy source

Implemented in Botan::Getentropy, Botan::Intel_Rdseed, and Botan::Win32_EntropySource.

Referenced by create().

operator=() [1/2]

Entropy_Source & Botan::Entropy_Source::operator= ( const Entropy_Source & other )

delete

References Entropy_Source().

operator=() [2/2]

Entropy_Source & Botan::Entropy_Source::operator= ( Entropy_Source && other )

delete

References Entropy_Source().

poll()

virtual size_t Botan::Entropy_Source::poll ( RandomNumberGenerator & rng )

pure virtual

Perform an entropy gathering poll

Parameters

Random Number Generators

will be provided with entropy via calls to add_entropy

Returns

conservative estimate of actual entropy added to rng during poll

Any implementation of this function should be thread safe; it may be called concurrently in multiple threads if multiple stateful RNGs reseed across different threads.

TODO(Botan4) make this member function const

Implemented in Botan::Getentropy, Botan::Intel_Rdseed, and Botan::Win32_EntropySource.

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

• src/lib/entropy/entropy_src.h
• src/lib/entropy/entropy_srcs.cpp