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 #ifndef AUTO_WINSOCK
   8 #ifdef WINSOCK_TWO
   9 #include <winsock2.h>
  10 #else
  11 #include <winsock.h>
  12 #endif
  13 #endif
  14 #include <stdio.h>
  15
  16 #include "putty.h"
  17 #include "ssh.h"
  18 #include "storage.h"
  19
  20 /*
  21  * GetSystemPowerStatus function.
  22  */
  23 typedef BOOL (WINAPI *gsps_t)(LPSYSTEM_POWER_STATUS);
  24 static gsps_t gsps;
  25
  26 /*
  27  * This function is called once, at PuTTY startup, and will do some
  28  * seriously silly things like listing directories and getting disk
  29  * free space and a process snapshot.
  30  */
  31
  32 void noise_get_heavy(void (*func) (void *, int)) {
  33     HANDLE srch;
  34     WIN32_FIND_DATA finddata;
  35     char winpath[MAX_PATH+3];
  36     HMODULE mod;
  37
  38     GetWindowsDirectory(winpath, sizeof(winpath));
  39     strcat(winpath, "\\*");
  40     srch = FindFirstFile(winpath, &finddata);
  41     if (srch != INVALID_HANDLE_VALUE) {
  42         do {
  43             func(&finddata, sizeof(finddata));
  44         } while (FindNextFile(srch, &finddata));
  45         FindClose(srch);
  46     }
  47
  48     read_random_seed(func);
  49
  50     gsps = NULL;
  51     mod = GetModuleHandle("KERNEL32");
  52     if (mod) {
  53         gsps = (gsps_t)GetProcAddress(mod, "GetSystemPowerStatus");
  54     }
  55 }
  56
  57 void random_save_seed(void) {
  58     int len;
  59     void *data;
  60
  61     random_get_savedata(&data, &len);
  62     write_random_seed(data, len);
  63 }
  64
  65 /*
  66  * This function is called every time the random pool needs
  67  * stirring, and will acquire the system time in all available
  68  * forms and the battery status.
  69  */
  70 void noise_get_light(void (*func) (void *, int)) {
  71     SYSTEMTIME systime;
  72     DWORD adjust[2];
  73     BOOL rubbish;
  74     SYSTEM_POWER_STATUS pwrstat;
  75
  76     GetSystemTime(&systime);
  77     func(&systime, sizeof(systime));
  78
  79     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
  80     func(&adjust, sizeof(adjust));
  81
  82     /*
  83      * Call GetSystemPowerStatus if present.
  84      */
  85     if (gsps) {
  86         if (gsps(&pwrstat))
  87             func(&pwrstat, sizeof(pwrstat));
  88     }
  89 }
  90
  91 /*
  92  * This function is called on every keypress or mouse move, and
  93  * will add the current Windows time and performance monitor
  94  * counter to the noise pool. It gets the scan code or mouse
  95  * position passed in.
  96  */
  97 void noise_ultralight(DWORD data) {
  98     DWORD wintime;
  99     LARGE_INTEGER perftime;
 100
 101     random_add_noise(&data, sizeof(DWORD));
 102
 103     wintime = GetTickCount();
 104     random_add_noise(&wintime, sizeof(DWORD));
 105
 106     if (QueryPerformanceCounter(&perftime))
 107         random_add_noise(&perftime, sizeof(perftime));
 108 }