Botan  2.15.0
Crypto and TLS for C++11
Public Member Functions | Static Public Member Functions | List of all members
Botan::Win32_EntropySource Class Referencefinal

#include <es_win32.h>

Inheritance diagram for Botan::Win32_EntropySource:
Botan::Entropy_Source

Public Member Functions

std::string name () const override
 
size_t poll (RandomNumberGenerator &rng) override
 

Static Public Member Functions

static std::unique_ptr< Entropy_Sourcecreate (const std::string &type)
 

Detailed Description

Win32 Entropy Source

Definition at line 18 of file es_win32.h.

Member Function Documentation

◆ create()

std::unique_ptr< Entropy_Source > Botan::Entropy_Source::create ( const std::string &  type)
staticinherited

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 107 of file entropy_srcs.cpp.

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

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

108  {
109 #if defined(BOTAN_HAS_SYSTEM_RNG)
110  if(name == "system_rng" || name == "win32_cryptoapi")
111  {
112  return std::unique_ptr<Entropy_Source>(new System_RNG_EntropySource);
113  }
114 #endif
115 
116 #if defined(BOTAN_HAS_PROCESSOR_RNG)
117  if(name == "hwrng" || name == "rdrand" || name == "p9_darn")
118  {
120  {
121  return std::unique_ptr<Entropy_Source>(new Processor_RNG_EntropySource);
122  }
123  }
124 #endif
125 
126 #if defined(BOTAN_HAS_ENTROPY_SRC_RDSEED)
127  if(name == "rdseed")
128  {
129  return std::unique_ptr<Entropy_Source>(new Intel_Rdseed);
130  }
131 #endif
132 
133 #if defined(BOTAN_HAS_ENTROPY_SRC_GETENTROPY)
134  if(name == "getentropy")
135  {
136  return std::unique_ptr<Entropy_Source>(new Getentropy);
137  }
138 #endif
139 
140 #if defined(BOTAN_HAS_ENTROPY_SRC_DEV_RANDOM)
141  if(name == "dev_random")
142  {
143  return std::unique_ptr<Entropy_Source>(new Device_EntropySource(BOTAN_SYSTEM_RNG_POLL_DEVICES));
144  }
145 #endif
146 
147 #if defined(BOTAN_HAS_ENTROPY_SRC_PROC_WALKER)
148  if(name == "proc_walk" && OS::running_in_privileged_state() == false)
149  {
150  const std::string root_dir = BOTAN_ENTROPY_PROC_FS_PATH;
151  if(!root_dir.empty())
152  return std::unique_ptr<Entropy_Source>(new ProcWalking_EntropySource(root_dir));
153  }
154 #endif
155 
156 #if defined(BOTAN_HAS_ENTROPY_SRC_WIN32)
157  if(name == "system_stats")
158  {
159  return std::unique_ptr<Entropy_Source>(new Win32_EntropySource);
160  }
161 #endif
162 
164  return std::unique_ptr<Entropy_Source>();
165  }
virtual std::string name() const =0
bool running_in_privileged_state()
Definition: os_utils.cpp:143
#define BOTAN_UNUSED(...)
Definition: assert.h:142
static bool available()

◆ name()

std::string Botan::Win32_EntropySource::name ( ) const
inlineoverridevirtual
Returns
name identifying this entropy source

Implements Botan::Entropy_Source.

Definition at line 21 of file es_win32.h.

21 { return "system_stats"; }

◆ poll()

size_t Botan::Win32_EntropySource::poll ( RandomNumberGenerator rng)
overridevirtual

Perform an entropy gathering poll

Parameters
rngwill be provided with entropy via calls to add_entropy
Returns
conservative estimate of actual entropy added to rng during poll

Implements Botan::Entropy_Source.

Definition at line 15 of file es_win32.cpp.

References Botan::RandomNumberGenerator::add_entropy_T().

16  {
17  rng.add_entropy_T(::GetTickCount());
18  rng.add_entropy_T(::GetMessagePos());
19  rng.add_entropy_T(::GetMessageTime());
20  rng.add_entropy_T(::GetInputState());
21 
22  rng.add_entropy_T(::GetCurrentProcessId());
23  rng.add_entropy_T(::GetCurrentThreadId());
24 
25  SYSTEM_INFO sys_info;
26  ::GetSystemInfo(&sys_info);
27  rng.add_entropy_T(sys_info);
28 
29  MEMORYSTATUSEX mem_info;
30  ::GlobalMemoryStatusEx(&mem_info);
31  rng.add_entropy_T(mem_info);
32 
33  POINT point;
34  ::GetCursorPos(&point);
35  rng.add_entropy_T(point);
36 
37  ::GetCaretPos(&point);
38  rng.add_entropy_T(point);
39 
40  /*
41  Potential other sources to investigate
42 
43  GetProductInfo
44  GetComputerNameExA
45  GetSystemFirmwareTable
46  GetVersionExA
47  GetProcessorSystemCycleTime
48  GetProcessHandleCount(GetCurrentProcess())
49  GetThreadTimes(GetCurrentThread())
50  QueryThreadCycleTime
51  QueryIdleProcessorCycleTime
52  QueryUnbiasedInterruptTime
53  */
54 
55  // We assume all of the above is basically junk
56  return 0;
57  }

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