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  * GetSystemPowerStatus function.
  14  */
  15 typedef BOOL(WINAPI * gsps_t) (LPSYSTEM_POWER_STATUS);
  16 static gsps_t gsps;
  17
  18 /*
  19  * This function is called once, at PuTTY startup, and will do some
  20  * seriously silly things like listing directories and getting disk
  21  * free space and a process snapshot.
  22  */
  23
  24 void noise_get_heavy(void (*func) (void *, int))
  25 {
  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     /* Update the seed immediately, in case another instance uses it. */
  43     random_save_seed();
  44
  45     gsps = NULL;
  46     mod = GetModuleHandle("KERNEL32");
  47     if (mod) {
  48         gsps = (gsps_t) GetProcAddress(mod, "GetSystemPowerStatus");
  49     }
  50 }
  51
  52 void random_save_seed(void)
  53 {
  54     int len;
  55     void *data;
  56
  57     if (random_active) {
  58         random_get_savedata(&data, &len);
  59         write_random_seed(data, len);
  60         sfree(data);
  61     }
  62 }
  63
  64 /*
  65  * This function is called every time the random pool needs
  66  * stirring, and will acquire the system time in all available
  67  * forms and the battery status.
  68  */
  69 void noise_get_light(void (*func) (void *, int))
  70 {
  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 a timer, and it will monitor
  93  * frequently changing quantities such as the state of physical and
  94  * virtual memory, the state of the process's message queue, which
  95  * window is in the foreground, which owns the clipboard, etc.
  96  */
  97 void noise_regular(void)
  98 {
  99     HWND w;
 100     DWORD z;
 101     POINT pt;
 102     MEMORYSTATUS memstat;
 103     FILETIME times[4];
 104
 105     w = GetForegroundWindow();
 106     random_add_noise(&w, sizeof(w));
 107     w = GetCapture();
 108     random_add_noise(&w, sizeof(w));
 109     w = GetClipboardOwner();
 110     random_add_noise(&w, sizeof(w));
 111     z = GetQueueStatus(QS_ALLEVENTS);
 112     random_add_noise(&z, sizeof(z));
 113
 114     GetCursorPos(&pt);
 115     random_add_noise(&pt, sizeof(pt));
 116
 117     GlobalMemoryStatus(&memstat);
 118     random_add_noise(&memstat, sizeof(memstat));
 119
 120     GetThreadTimes(GetCurrentThread(), times, times + 1, times + 2,
 121                    times + 3);
 122     random_add_noise(&times, sizeof(times));
 123     GetProcessTimes(GetCurrentProcess(), times, times + 1, times + 2,
 124                     times + 3);
 125     random_add_noise(&times, sizeof(times));
 126 }
 127
 128 /*
 129  * This function is called on every keypress or mouse move, and
 130  * will add the current Windows time and performance monitor
 131  * counter to the noise pool. It gets the scan code or mouse
 132  * position passed in.
 133  */
 134 void noise_ultralight(unsigned long data)
 135 {
 136     DWORD wintime;
 137     LARGE_INTEGER perftime;
 138
 139     random_add_noise(&data, sizeof(DWORD));
 140
 141     wintime = GetTickCount();
 142     random_add_noise(&wintime, sizeof(DWORD));
 143
 144     if (QueryPerformanceCounter(&perftime))
 145         random_add_noise(&perftime, sizeof(perftime));
 146 }