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     SYSTEM_POWER_STATUS pwrstat;
  62
  63     GetSystemTime(&systime);
  64     func(&systime, sizeof(systime));
  65
  66     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  67     func(&adjust, sizeof(adjust));
  68 }
  69
  70 /*
  71  * This function is called on a timer, and it will monitor
  72  * frequently changing quantities such as the state of physical and
  73  * virtual memory, the state of the process's message queue, which
  74  * window is in the foreground, which owns the clipboard, etc.
  75  */
  76 void noise_regular(void)
  77 {
  78     HWND w;
  79     DWORD z;
  80     POINT pt;
  81     MEMORYSTATUS memstat;
  82     FILETIME times[4];
  83
  84     w = GetForegroundWindow();
  85     random_add_noise(&w, sizeof(w));
  86     w = GetCapture();
  87     random_add_noise(&w, sizeof(w));
  88     w = GetClipboardOwner();
  89     random_add_noise(&w, sizeof(w));
  90     z = GetQueueStatus(QS_ALLEVENTS);
  91     random_add_noise(&z, sizeof(z));
  92
  93     GetCursorPos(&pt);
  94     random_add_noise(&pt, sizeof(pt));
  95
  96     GlobalMemoryStatus(&memstat);
  97     random_add_noise(&memstat, sizeof(memstat));
  98
  99     GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
 100                    times + 3);
 101     random_add_noise(&times, sizeof(times));
 102     GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
 103                     times + 3);
 104     random_add_noise(&times, sizeof(times));
 105 }
 106
 107 /*
 108  * This function is called on every keypress or mouse move, and
 109  * will add the current Windows time and performance monitor
 110  * counter to the noise pool. It gets the scan code or mouse
 111  * position passed in.
 112  */
 113 void noise_ultralight(unsigned long data)
 114 {
 115     DWORD wintime;
 116     LARGE_INTEGER perftime;
 117
 118     random_add_noise(&data, sizeof(DWORD));
 119
 120     wintime = GetTickCount();
 121     random_add_noise(&wintime, sizeof(DWORD));
 122
 123     if (QueryPerformanceCounter(&perftime))
 124         random_add_noise(&perftime, sizeof(perftime));
 125 }