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 <windows.h>
   7 #include <stdio.h>
   8
   9 #include "putty.h"
  10 #include "ssh.h"
  11 #include "storage.h"
  12
  13 /*
  14  * GetSystemPowerStatus function.
  15  */
  16 typedef BOOL (WINAPI *gsps_t)(LPSYSTEM_POWER_STATUS);
  17 static gsps_t gsps;
  18
  19 /*
  20  * This function is called once, at PuTTY startup, and will do some
  21  * seriously silly things like listing directories and getting disk
  22  * free space and a process snapshot.
  23  */
  24
  25 void noise_get_heavy(void (*func) (void *, int)) {
  26     HANDLE srch;
  27     WIN32_FIND_DATA finddata;
  28     char winpath[MAX_PATH+3];
  29     HMODULE mod;
  30
  31     GetWindowsDirectory(winpath, sizeof(winpath));
  32     strcat(winpath, "\\*");
  33     srch = FindFirstFile(winpath, &finddata);
  34     if (srch != INVALID_HANDLE_VALUE) {
  35         do {
  36             func(&finddata, sizeof(finddata));
  37         } while (FindNextFile(srch, &finddata));
  38         FindClose(srch);
  39     }
  40
  41     read_random_seed(func);
  42
  43     gsps = NULL;
  44     mod = GetModuleHandle("KERNEL32");
  45     if (mod) {
  46         gsps = (gsps_t)GetProcAddress(mod, "GetSystemPowerStatus");
  47     }
  48 }
  49
  50 void random_save_seed(void) {
  51     int len;
  52     void *data;
  53
  54     random_get_savedata(&data, &len);
  55     write_random_seed(data, len);
  56 }
  57
  58 /*
  59  * This function is called every time the random pool needs
  60  * stirring, and will acquire the system time in all available
  61  * forms and the battery status.
  62  */
  63 void noise_get_light(void (*func) (void *, int)) {
  64     SYSTEMTIME systime;
  65     DWORD adjust[2];
  66     BOOL rubbish;
  67     SYSTEM_POWER_STATUS pwrstat;
  68
  69     GetSystemTime(&systime);
  70     func(&systime, sizeof(systime));
  71
  72     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  73     func(&adjust, sizeof(adjust));
  74
  75     /*
  76      * Call GetSystemPowerStatus if present.
  77      */
  78     if (gsps) {
  79         if (gsps(&pwrstat))
  80             func(&pwrstat, sizeof(pwrstat));
  81     }
  82 }
  83
  84 /*
  85  * This function is called on a timer, and it will monitor
  86  * frequently changing quantities such as the state of physical and
  87  * virtual memory, the state of the process's message queue, which
  88  * window is in the foreground, which owns the clipboard, etc.
  89  */
  90 void noise_regular(void) {
  91     HWND w;
  92     DWORD z;
  93     POINT pt;
  94     MEMORYSTATUS memstat;
  95     FILETIME times[4];
  96
  97     w = GetForegroundWindow(); random_add_noise(&w, sizeof(w));
  98     w = GetCapture(); random_add_noise(&w, sizeof(w));
  99     w = GetClipboardOwner(); random_add_noise(&w, sizeof(w));
 100     z = GetQueueStatus(QS_ALLEVENTS); random_add_noise(&z, sizeof(z));
 101
 102     GetCursorPos(&pt); random_add_noise(&pt, sizeof(pt));
 103
 104     GlobalMemoryStatus(&memstat); random_add_noise(&memstat, sizeof(memstat));
 105
 106     GetThreadTimes(GetCurrentThread(), times, times+1, times+2, times+3);
 107     random_add_noise(&times, sizeof(times));
 108     GetProcessTimes(GetCurrentProcess(), times, times+1, times+2, times+3);
 109     random_add_noise(&times, sizeof(times));
 110 }
 111
 112 /*
 113  * This function is called on every keypress or mouse move, and
 114  * will add the current Windows time and performance monitor
 115  * counter to the noise pool. It gets the scan code or mouse
 116  * position passed in.
 117  */
 118 void noise_ultralight(DWORD data) {
 119     DWORD wintime;
 120     LARGE_INTEGER perftime;
 121
 122     random_add_noise(&data, sizeof(DWORD));
 123
 124     wintime = GetTickCount();
 125     random_add_noise(&wintime, sizeof(DWORD));
 126
 127     if (QueryPerformanceCounter(&perftime))
 128         random_add_noise(&perftime, sizeof(perftime));
 129 }