git.distorted.org.uk Git - u/mdw/putty/blob - windows/winnoise.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     DWORD pid;
  23     char winpath[MAX_PATH + 3];
  24
  25     GetWindowsDirectory(winpath, sizeof(winpath));
  26     strcat(winpath, "\\*");
  27     srch = FindFirstFile(winpath, &finddata);
  28     if (srch != INVALID_HANDLE_VALUE) {
  29         do {
  30             func(&finddata, sizeof(finddata));
  31         } while (FindNextFile(srch, &finddata));
  32         FindClose(srch);
  33     }
  34
  35     pid = GetCurrentProcessId();
  36     func(&pid, sizeof(pid));
  37
  38     read_random_seed(func);
  39     /* Update the seed immediately, in case another instance uses it. */
  40     random_save_seed();
  41 }
  42
  43 void random_save_seed(void)
  44 {
  45     int len;
  46     void *data;
  47
  48     if (random_active) {
  49         random_get_savedata(&data, &len);
  50         write_random_seed(data, len);
  51         sfree(data);
  52     }
  53 }
  54
  55 /*
  56  * This function is called every time the random pool needs
  57  * stirring, and will acquire the system time in all available
  58  * forms.
  59  */
  60 void noise_get_light(void (*func) (void *, int))
  61 {
  62     SYSTEMTIME systime;
  63     DWORD adjust[2];
  64     BOOL rubbish;
  65
  66     GetSystemTime(&systime);
  67     func(&systime, sizeof(systime));
  68
  69     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  70     func(&adjust, sizeof(adjust));
  71 }
  72
  73 /*
  74  * This function is called on a timer, and it will monitor
  75  * frequently changing quantities such as the state of physical and
  76  * virtual memory, the state of the process's message queue, which
  77  * window is in the foreground, which owns the clipboard, etc.
  78  */
  79 void noise_regular(void)
  80 {
  81     HWND w;
  82     DWORD z;
  83     POINT pt;
  84     MEMORYSTATUS memstat;
  85     FILETIME times[4];
  86
  87     w = GetForegroundWindow();
  88     random_add_noise(&w, sizeof(w));
  89     w = GetCapture();
  90     random_add_noise(&w, sizeof(w));
  91     w = GetClipboardOwner();
  92     random_add_noise(&w, sizeof(w));
  93     z = GetQueueStatus(QS_ALLEVENTS);
  94     random_add_noise(&z, sizeof(z));
  95
  96     GetCursorPos(&pt);
  97     random_add_noise(&pt, sizeof(pt));
  98
  99     GlobalMemoryStatus(&memstat);
 100     random_add_noise(&memstat, sizeof(memstat));
 101
 102     GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
 103                    times + 3);
 104     random_add_noise(&times, sizeof(times));
 105     GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
 106                     times + 3);
 107     random_add_noise(&times, sizeof(times));
 108 }
 109
 110 /*
 111  * This function is called on every keypress or mouse move, and
 112  * will add the current Windows time and performance monitor
 113  * counter to the noise pool. It gets the scan code or mouse
 114  * position passed in.
 115  */
 116 void noise_ultralight(unsigned long data)
 117 {
 118     DWORD wintime;
 119     LARGE_INTEGER perftime;
 120
 121     random_add_noise(&data, sizeof(DWORD));
 122
 123     wintime = GetTickCount();
 124     random_add_noise(&wintime, sizeof(DWORD));
 125
 126     if (QueryPerformanceCounter(&perftime))
 127         random_add_noise(&perftime, sizeof(perftime));
 128 }