git.distorted.org.uk Git - u/mdw/putty/blob - noise.c

   1 /*
   2  * Noise generation for PuTTY's cryptographic random number
   3  * generator.
   4  */
   5
   6 #include <stdio.h>
   7
   8 #include "putty.h"
   9 #include "ssh.h"
  10 #include "storage.h"
  11
  12 /*
  13  * This function is called once, at PuTTY startup, and will do some
  14  * seriously silly things like listing directories and getting disk
  15  * free space and a process snapshot.
  16  */
  17
  18 void noise_get_heavy(void (*func) (void *, int))
  19 {
  20     HANDLE srch;
  21     WIN32_FIND_DATA finddata;
  22     char winpath[MAX_PATH + 3];
  23
  24     GetWindowsDirectory(winpath, sizeof(winpath));
  25     strcat(winpath, "\\*");
  26     srch = FindFirstFile(winpath, &finddata);
  27     if (srch != INVALID_HANDLE_VALUE) {
  28         do {
  29             func(&finddata, sizeof(finddata));
  30         } while (FindNextFile(srch, &finddata));
  31         FindClose(srch);
  32     }
  33
  34     read_random_seed(func);
  35     /* Update the seed immediately, in case another instance uses it. */
  36     random_save_seed();
  37 }
  38
  39 void random_save_seed(void)
  40 {
  41     int len;
  42     void *data;
  43
  44     if (random_active) {
  45         random_get_savedata(&data, &len);
  46         write_random_seed(data, len);
  47         sfree(data);
  48     }
  49 }
  50
  51 /*
  52  * This function is called every time the random pool needs
  53  * stirring, and will acquire the system time in all available
  54  * forms and the battery status.
  55  */
  56 void noise_get_light(void (*func) (void *, int))
  57 {
  58     SYSTEMTIME systime;
  59     DWORD adjust[2];
  60     BOOL rubbish;
  61
  62     GetSystemTime(&systime);
  63     func(&systime, sizeof(systime));
  64
  65     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  66     func(&adjust, sizeof(adjust));
  67 }
  68
  69 /*
  70  * This function is called on a timer, and it will monitor
  71  * frequently changing quantities such as the state of physical and
  72  * virtual memory, the state of the process's message queue, which
  73  * window is in the foreground, which owns the clipboard, etc.
  74  */
  75 void noise_regular(void)
  76 {
  77     HWND w;
  78     DWORD z;
  79     POINT pt;
  80     MEMORYSTATUS memstat;
  81     FILETIME times[4];
  82
  83     w = GetForegroundWindow();
  84     random_add_noise(&w, sizeof(w));
  85     w = GetCapture();
  86     random_add_noise(&w, sizeof(w));
  87     w = GetClipboardOwner();
  88     random_add_noise(&w, sizeof(w));
  89     z = GetQueueStatus(QS_ALLEVENTS);
  90     random_add_noise(&z, sizeof(z));
  91
  92     GetCursorPos(&pt);
  93     random_add_noise(&pt, sizeof(pt));
  94
  95     GlobalMemoryStatus(&memstat);
  96     random_add_noise(&memstat, sizeof(memstat));
  97
  98     GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
  99                    times + 3);
 100     random_add_noise(&times, sizeof(times));
 101     GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
 102                     times + 3);
 103     random_add_noise(&times, sizeof(times));
 104 }
 105
 106 /*
 107  * This function is called on every keypress or mouse move, and
 108  * will add the current Windows time and performance monitor
 109  * counter to the noise pool. It gets the scan code or mouse
 110  * position passed in.
 111  */
 112 void noise_ultralight(unsigned long data)
 113 {
 114     DWORD wintime;
 115     LARGE_INTEGER perftime;
 116
 117     random_add_noise(&data, sizeof(DWORD));
 118
 119     wintime = GetTickCount();
 120     random_add_noise(&wintime, sizeof(DWORD));
 121
 122     if (QueryPerformanceCounter(&perftime))
 123         random_add_noise(&perftime, sizeof(perftime));
 124 }