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
virtual size_t	poll (RandomNumberGenerator &rng)=0
virtual	~Entropy_Source ()=default

Static Public Member Functions
static std::unique_ptr< Entropy_Source >	create (const std::string &type)

Detailed Description

Abstract interface to a source of entropy

Definition at line 25 of file entropy_src.h.

Constructor & Destructor Documentation

Botan::Entropy_Source::Entropy_Source ( )

default

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

delete

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

delete

virtual Botan::Entropy_Source::~Entropy_Source ( )

virtualdefault

Member Function Documentation

std::unique_ptr< Entropy_Source > Botan::Entropy_Source::create ( const std::string &  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 67 of file entropy_srcs.cpp.

References BOTAN_UNUSED, and Botan::OS::running_in_privileged_state().

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

   {
#if defined(BOTAN_HAS_SYSTEM_RNG)
   if(name == "system_rng" || name == "win32_cryptoapi")
      {
      return std::unique_ptr<Entropy_Source>(new System_RNG_EntropySource);
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_RDRAND)
   if(name == "rdrand")
      {
      return std::unique_ptr<Entropy_Source>(new Intel_Rdrand);
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_RDSEED)
   if(name == "rdseed")
      {
      return std::unique_ptr<Entropy_Source>(new Intel_Rdseed);
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_DARN)
   if(name == "p9_darn")
      {
      return std::unique_ptr<Entropy_Source>(new POWER9_DARN);
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_GETENTROPY)
   if(name == "getentropy")
      {
      return std::unique_ptr<Entropy_Source>(new Getentropy);
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_DEV_RANDOM)
   if(name == "dev_random")
      {
      return std::unique_ptr<Entropy_Source>(new Device_EntropySource(BOTAN_SYSTEM_RNG_POLL_DEVICES));
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_PROC_WALKER)
   if(name == "proc_walk" && OS::running_in_privileged_state() == false)
      {
      const std::string root_dir = BOTAN_ENTROPY_PROC_FS_PATH;
      if(!root_dir.empty())
         return std::unique_ptr<Entropy_Source>(new ProcWalking_EntropySource(root_dir));
      }
#endif

#if defined(BOTAN_HAS_ENTROPY_SRC_WIN32)
   if(name == "system_stats")
      {
      return std::unique_ptr<Entropy_Source>(new Win32_EntropySource);
      }
#endif

   BOTAN_UNUSED(name);
   return std::unique_ptr<Entropy_Source>();
   }

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

pure virtual

Returns

name identifying this entropy source

Implemented in Botan::ProcWalking_EntropySource, Botan::Device_EntropySource, Botan::Getentropy, Botan::Intel_Rdrand, Botan::Intel_Rdseed, Botan::Win32_EntropySource, and Botan::POWER9_DARN.

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

delete

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

pure virtual

Perform an entropy gathering poll

Parameters

rng	will be provided with entropy via calls to add_entropy

Returns

conservative estimate of actual entropy added to rng during poll

Implemented in Botan::ProcWalking_EntropySource, Botan::Device_EntropySource, Botan::Getentropy, Botan::Intel_Rdrand, Botan::Intel_Rdseed, Botan::Win32_EntropySource, and Botan::POWER9_DARN.

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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