Improved entropy gathering.

[u/mdw/putty] / noise.c

diff --git a/noise.c b/noise.c
index 88b13a9..c5966a7 100644 (file)
--- a/noise.c
+++ b/noise.c
@@ -11,6 +11,12 @@
 #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.
@@ -20,6 +26,7 @@ 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, "\\*");
@@ -32,6 +39,12 @@ void noise_get_heavy(void (*func) (void *, int)) {
     }
 
     read_random_seed(func);
+
+    gsps = NULL;
+    mod = GetModuleHandle("KERNEL32");
+    if (mod) {
+        gsps = (gsps_t)GetProcAddress(mod, "GetSystemPowerStatus");
+    }
 }
 
 void random_save_seed(void) {
@@ -59,10 +72,41 @@ void noise_get_light(void (*func) (void *, int)) {
     GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish);
     func(&adjust, sizeof(adjust));
 
-#ifndef WIN32S_COMPAT
-    if (GetSystemPowerStatus(&pwrstat))
-       func(&pwrstat, sizeof(pwrstat));
-#endif
+    /*
+     * Call GetSystemPowerStatus if present.
+     */
+    if (gsps) {
+        if (gsps(&pwrstat))
+            func(&pwrstat, sizeof(pwrstat));
+    }
+}
+
+/*
+ * This function is called on a timer, and it will monitor
+ * frequently changing quantities such as the state of physical and
+ * virtual memory, the state of the process's message queue, which
+ * window is in the foreground, which owns the clipboard, etc.
+ */
+void noise_regular(void) {
+    HWND w;
+    DWORD z;
+    POINT pt;
+    MEMORYSTATUS memstat;
+    FILETIME times[4];
+
+    w = GetForegroundWindow(); random_add_noise(&w, sizeof(w));
+    w = GetCapture(); random_add_noise(&w, sizeof(w));
+    w = GetClipboardOwner(); random_add_noise(&w, sizeof(w));
+    z = GetQueueStatus(QS_ALLEVENTS); random_add_noise(&z, sizeof(z));
+
+    GetCursorPos(&pt); random_add_noise(&pt, sizeof(pt));
+
+    GlobalMemoryStatus(&memstat); random_add_noise(&memstat, sizeof(memstat));
+
+    GetThreadTimes(GetCurrentThread(), times, times+1, times+2, times+3);
+    random_add_noise(&times, sizeof(times));
+    GetProcessTimes(GetCurrentProcess(), times, times+1, times+2, times+3);
+    random_add_noise(&times, sizeof(times));
 }
 
 /*