2 * Noise generation for PuTTY's cryptographic random number
12 static char seedpath
[2*MAX_PATH
+10] = "\0";
15 * Find the random seed file path and store it in `seedpath'.
17 static void get_seedpath(void) {
21 size
= sizeof(seedpath
);
23 if (RegOpenKey(HKEY_CURRENT_USER
, PUTTY_REG_POS
, &rkey
)==ERROR_SUCCESS
) {
24 int ret
= RegQueryValueEx(rkey
, "RandSeedFile",
25 0, &type
, seedpath
, &size
);
26 if (ret
!= ERROR_SUCCESS
|| type
!= REG_SZ
)
35 len
= GetEnvironmentVariable("HOMEDRIVE", seedpath
, sizeof(seedpath
));
36 ret
= GetEnvironmentVariable("HOMEPATH", seedpath
+len
,
37 sizeof(seedpath
)-len
);
38 if (ret
== 0) { /* probably win95; store in \WINDOWS */
39 GetWindowsDirectory(seedpath
, sizeof(seedpath
));
40 len
= strlen(seedpath
);
43 strcpy(seedpath
+len
, "\\PUTTY.RND");
48 * This function is called once, at PuTTY startup, and will do some
49 * seriously silly things like listing directories and getting disk
50 * free space and a process snapshot.
53 void noise_get_heavy(void (*func
) (void *, int)) {
56 WIN32_FIND_DATA finddata
;
57 char winpath
[MAX_PATH
+3];
59 GetWindowsDirectory(winpath
, sizeof(winpath
));
60 strcat(winpath
, "\\*");
61 srch
= FindFirstFile(winpath
, &finddata
);
62 if (srch
!= INVALID_HANDLE_VALUE
) {
64 func(&finddata
, sizeof(finddata
));
65 } while (FindNextFile(srch
, &finddata
));
72 seedf
= CreateFile(seedpath
, GENERIC_READ
,
73 FILE_SHARE_READ
| FILE_SHARE_WRITE
,
74 NULL
, OPEN_EXISTING
, 0, NULL
);
76 if (seedf
!= INVALID_HANDLE_VALUE
) {
81 if (ReadFile(seedf
, buf
, sizeof(buf
), &len
, NULL
) && len
)
90 void random_save_seed(void) {
96 seedf
= CreateFile(seedpath
, GENERIC_WRITE
, 0,
97 NULL
, CREATE_ALWAYS
, FILE_ATTRIBUTE_NORMAL
, NULL
);
99 if (seedf
!= INVALID_HANDLE_VALUE
) {
104 random_get_savedata(&data
, &len
);
105 WriteFile(seedf
, data
, len
, &lenwritten
, NULL
);
111 * This function is called every time the random pool needs
112 * stirring, and will acquire the system time in all available
113 * forms and the battery status.
115 void noise_get_light(void (*func
) (void *, int)) {
119 SYSTEM_POWER_STATUS pwrstat
;
121 GetSystemTime(&systime
);
122 func(&systime
, sizeof(systime
));
124 GetSystemTimeAdjustment(&adjust
[0], &adjust
[1], &rubbish
);
125 func(&adjust
, sizeof(adjust
));
127 #ifndef WIN32S_COMPAT
128 if (GetSystemPowerStatus(&pwrstat
))
129 func(&pwrstat
, sizeof(pwrstat
));
134 * This function is called on every keypress or mouse move, and
135 * will add the current Windows time and performance monitor
136 * counter to the noise pool. It gets the scan code or mouse
137 * position passed in.
139 void noise_ultralight(DWORD data
) {
141 LARGE_INTEGER perftime
;
143 random_add_noise(&data
, sizeof(DWORD
));
145 wintime
= GetTickCount();
146 random_add_noise(&wintime
, sizeof(DWORD
));
148 if (QueryPerformanceCounter(&perftime
))
149 random_add_noise(&perftime
, sizeof(perftime
));