Botan  2.1.0
Crypto and TLS for C++11
es_win32.cpp
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1 /*
2 * Win32 EntropySource
3 * (C) 1999-2009,2016 Jack Lloyd
4 *
5 * Botan is released under the Simplified BSD License (see license.txt)
6 */
7 
8 #include <botan/internal/es_win32.h>
9 #define NOMINMAX 1
10 #include <windows.h>
11 #include <tlhelp32.h>
12 
13 namespace Botan {
14 
15 /**
16 * Win32 poll using stats functions including Tooltip32
17 */
19  {
20  /*
21  First query a bunch of basic statistical stuff
22  */
23  rng.add_entropy_T(::GetTickCount());
24  rng.add_entropy_T(::GetMessagePos());
25  rng.add_entropy_T(::GetMessageTime());
26  rng.add_entropy_T(::GetInputState());
27 
28  rng.add_entropy_T(::GetCurrentProcessId());
29  rng.add_entropy_T(::GetCurrentThreadId());
30 
31  SYSTEM_INFO sys_info;
32  ::GetSystemInfo(&sys_info);
33  rng.add_entropy_T(sys_info);
34 
35  MEMORYSTATUSEX mem_info;
36  ::GlobalMemoryStatusEx(&mem_info);
37  rng.add_entropy_T(mem_info);
38 
39  POINT point;
40  ::GetCursorPos(&point);
41  rng.add_entropy_T(point);
42 
43  ::GetCaretPos(&point);
44  rng.add_entropy_T(point);
45 
46  /*
47  Now use the Tooltip library to iterate through various objects on
48  the system, including processes, threads, and heap objects.
49  */
50 
51  HANDLE snapshot = ::CreateToolhelp32Snapshot(TH32CS_SNAPALL, 0);
52  size_t bits = 0;
53 
54 #define TOOLHELP32_ITER(DATA_TYPE, FUNC_FIRST, FUNC_NEXT) \
55  if(bits < 256) \
56  { \
57  DATA_TYPE info; \
58  info.dwSize = sizeof(DATA_TYPE); \
59  if(FUNC_FIRST(snapshot, &info)) \
60  { \
61  do \
62  { \
63  rng.add_entropy_T(info); \
64  bits += 4; \
65  } while(FUNC_NEXT(snapshot, &info)); \
66  } \
67  }
68 
69  TOOLHELP32_ITER(MODULEENTRY32, ::Module32First, ::Module32Next);
70  TOOLHELP32_ITER(PROCESSENTRY32, ::Process32First, ::Process32Next);
71  TOOLHELP32_ITER(THREADENTRY32, ::Thread32First, ::Thread32Next);
72 
73 #undef TOOLHELP32_ITER
74 
75  if(bits <= 256)
76  {
77  HEAPLIST32 heap_list;
78  heap_list.dwSize = sizeof(HEAPLIST32);
79 
80  if(::Heap32ListFirst(snapshot, &heap_list))
81  {
82  do
83  {
84  rng.add_entropy_T(heap_list);
85 
86  HEAPENTRY32 heap_entry;
87  heap_entry.dwSize = sizeof(HEAPENTRY32);
88  if(::Heap32First(&heap_entry,
89  heap_list.th32ProcessID,
90  heap_list.th32HeapID))
91  {
92  do
93  {
94  rng.add_entropy_T(heap_entry);
95  bits += 4;
96  } while(::Heap32Next(&heap_entry));
97  }
98 
99  if(bits >= 256)
100  break;
101 
102  } while(::Heap32ListNext(snapshot, &heap_list));
103  }
104  }
105 
106  ::CloseHandle(snapshot);
107 
108  return bits;
109  }
110 
111 }
void add_entropy_T(const T &t)
Definition: rng.h:60
size_t poll(RandomNumberGenerator &rng) override
Definition: es_win32.cpp:18
Definition: alg_id.cpp:13
#define TOOLHELP32_ITER(DATA_TYPE, FUNC_FIRST, FUNC_NEXT)