putty/noise.c

102 строки
2.3 KiB
C

/*
* Noise generation for PuTTY's cryptographic random number
* generator.
*/
#include <windows.h>
#include <stdio.h>
#include "putty.h"
#include "ssh.h"
#include "storage.h"
/*
* GetSystemPowerStatus function.
*/
typedef BOOL (WINAPI *gsps_t)(LPSYSTEM_POWER_STATUS);
static gsps_t gsps;
/*
* This function is called once, at PuTTY startup, and will do some
* seriously silly things like listing directories and getting disk
* free space and a process snapshot.
*/
void noise_get_heavy(void (*func) (void *, int)) {
HANDLE srch;
WIN32_FIND_DATA finddata;
char winpath[MAX_PATH+3];
HMODULE mod;
GetWindowsDirectory(winpath, sizeof(winpath));
strcat(winpath, "\\*");
srch = FindFirstFile(winpath, &finddata);
if (srch != INVALID_HANDLE_VALUE) {
do {
func(&finddata, sizeof(finddata));
} while (FindNextFile(srch, &finddata));
FindClose(srch);
}
read_random_seed(func);
gsps = NULL;
mod = GetModuleHandle("KERNEL32");
if (mod) {
gsps = (gsps_t)GetProcAddress(mod, "GetSystemPowerStatus");
}
}
void random_save_seed(void) {
int len;
void *data;
random_get_savedata(&data, &len);
write_random_seed(data, len);
}
/*
* This function is called every time the random pool needs
* stirring, and will acquire the system time in all available
* forms and the battery status.
*/
void noise_get_light(void (*func) (void *, int)) {
SYSTEMTIME systime;
DWORD adjust[2];
BOOL rubbish;
SYSTEM_POWER_STATUS pwrstat;
GetSystemTime(&systime);
func(&systime, sizeof(systime));
GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
func(&adjust, sizeof(adjust));
/*
* Call GetSystemPowerStatus if present.
*/
if (gsps) {
if (gsps(&pwrstat))
func(&pwrstat, sizeof(pwrstat));
}
}
/*
* This function is called on every keypress or mouse move, and
* will add the current Windows time and performance monitor
* counter to the noise pool. It gets the scan code or mouse
* position passed in.
*/
void noise_ultralight(DWORD data) {
DWORD wintime;
LARGE_INTEGER perftime;
random_add_noise(&data, sizeof(DWORD));
wintime = GetTickCount();
random_add_noise(&wintime, sizeof(DWORD));
if (QueryPerformanceCounter(&perftime))
random_add_noise(&perftime, sizeof(perftime));
}