Botan 2.19.2
Crypto and TLS for C&
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.

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 }
#define BOTAN_UNUSED(...)
Definition: assert.h:142
virtual std::string name() const =0
static bool available()
bool running_in_privileged_state()
Definition: os_utils.cpp:143

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().

◆ 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.

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 }

References Botan::RandomNumberGenerator::add_entropy_T().


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