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 {
  27     HANDLE srch;
  28     WIN32_FIND_DATA finddata;
  29     char winpath[MAX_PATH + 3];
  30     HMODULE mod;
  31
  32     GetWindowsDirectory(winpath, sizeof(winpath));
  33     strcat(winpath, "\\*");
  34     srch = FindFirstFile(winpath, &finddata);
  35     if (srch != INVALID_HANDLE_VALUE) {
  36         do {
  37             func(&finddata, sizeof(finddata));
  38         } while (FindNextFile(srch, &finddata));
  39         FindClose(srch);
  40     }
  41
  42     read_random_seed(func);
  43
  44     gsps = NULL;
  45     mod = GetModuleHandle("KERNEL32");
  46     if (mod) {
  47         gsps = (gsps_t) GetProcAddress(mod, "GetSystemPowerStatus");
  48     }
  49 }
  50
  51 void random_save_seed(void)
  52 {
  53     int len;
  54     void *data;
  55
  56     if (random_active) {
  57         random_get_savedata(&data, &len);
  58         write_random_seed(data, len);
  59     }
  60 }
  61
  62 /*
  63  * This function is called every time the random pool needs
  64  * stirring, and will acquire the system time in all available
  65  * forms and the battery status.
  66  */
  67 void noise_get_light(void (*func) (void *, int))
  68 {
  69     SYSTEMTIME systime;
  70     DWORD adjust[2];
  71     BOOL rubbish;
  72     SYSTEM_POWER_STATUS pwrstat;
  73
  74     GetSystemTime(&systime);
  75     func(&systime, sizeof(systime));
  76
  77     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  78     func(&adjust, sizeof(adjust));
  79
  80     /*
  81      * Call GetSystemPowerStatus if present.
  82      */
  83     if (gsps) {
  84         if (gsps(&pwrstat))
  85             func(&pwrstat, sizeof(pwrstat));
  86     }
  87 }
  88
  89 /*
  90  * This function is called on a timer, and it will monitor
  91  * frequently changing quantities such as the state of physical and
  92  * virtual memory, the state of the process's message queue, which
  93  * window is in the foreground, which owns the clipboard, etc.
  94  */
  95 void noise_regular(void)
  96 {
  97     HWND w;
  98     DWORD z;
  99     POINT pt;
 100     MEMORYSTATUS memstat;
 101     FILETIME times[4];
 102
 103     w = GetForegroundWindow();
 104     random_add_noise(&w, sizeof(w));
 105     w = GetCapture();
 106     random_add_noise(&w, sizeof(w));
 107     w = GetClipboardOwner();
 108     random_add_noise(&w, sizeof(w));
 109     z = GetQueueStatus(QS_ALLEVENTS);
 110     random_add_noise(&z, sizeof(z));
 111
 112     GetCursorPos(&pt);
 113     random_add_noise(&pt, sizeof(pt));
 114
 115     GlobalMemoryStatus(&memstat);
 116     random_add_noise(&memstat, sizeof(memstat));
 117
 118     GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
 119                    times + 3);
 120     random_add_noise(&times, sizeof(times));
 121     GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
 122                     times + 3);
 123     random_add_noise(&times, sizeof(times));
 124 }
 125
 126 /*
 127  * This function is called on every keypress or mouse move, and
 128  * will add the current Windows time and performance monitor
 129  * counter to the noise pool. It gets the scan code or mouse
 130  * position passed in.
 131  */
 132 void noise_ultralight(unsigned long data)
 133 {
 134     DWORD wintime;
 135     LARGE_INTEGER perftime;
 136
 137     random_add_noise(&data, sizeof(DWORD));
 138
 139     wintime = GetTickCount();
 140     random_add_noise(&wintime, sizeof(DWORD));
 141
 142     if (QueryPerformanceCounter(&perftime))
 143         random_add_noise(&perftime, sizeof(perftime));
 144 }