Initial checkin: beta 0.43

[originally from svn r11]

noise.c

@@ -0,0 +1,148 @@
+/*
+ * Noise generation for PuTTY's cryptographic random number
+ * generator.
+ */
+
+#include <windows.h>
+#include <stdio.h>
+
+#include "putty.h"
+#include "ssh.h"
+
+static char seedpath[2*MAX_PATH+10] = "\0";
+
+/*
+ * Find the random seed file path and store it in `seedpath'.
+ */
+static void get_seedpath(void) {
+    HKEY rkey;
+    DWORD type, size;
+
+    size = sizeof(seedpath);
+
+    if (RegOpenKey(HKEY_CURRENT_USER, PUTTY_REG_POS, &rkey)==ERROR_SUCCESS) {
+	int ret = RegQueryValueEx(rkey, "RandSeedFile",
+				  0, &type, seedpath, &size);
+	if (ret != ERROR_SUCCESS || type != REG_SZ)
+	    seedpath[0] = '\0';
+	RegCloseKey(rkey);
+    } else
+	seedpath[0] = '\0';
+
+    if (!seedpath[0]) {
+	int len, ret;
+
+	len = GetEnvironmentVariable("HOMEDRIVE", seedpath, sizeof(seedpath));
+	ret = GetEnvironmentVariable("HOMEPATH", seedpath+len,
+				      sizeof(seedpath)-len);
+	if (ret == 0) {		       /* probably win95; store in \WINDOWS */
+	    GetWindowsDirectory(seedpath, sizeof(seedpath));
+	    len = strlen(seedpath);
+	} else
+	    len += ret;
+	strcpy(seedpath+len, "\\PUTTY.RND");
+    }
+}
+
+/*
+ * 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;
+    HANDLE seedf;
+    WIN32_FIND_DATA finddata;
+    char winpath[MAX_PATH+3];
+
+    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);
+    }
+
+    if (!seedpath[0])
+	get_seedpath();
+
+    seedf = CreateFile(seedpath, GENERIC_READ,
+		       FILE_SHARE_READ | FILE_SHARE_WRITE,
+		       NULL, OPEN_EXISTING, 0, NULL);
+
+    if (seedf) {
+	while (1) {
+	    char buf[1024];
+	    DWORD len;
+
+	    if (ReadFile(seedf, buf, sizeof(buf), &len, NULL) && len)
+		func(buf, len);
+	    else
+		break;
+	}
+	CloseHandle(seedf);
+    }
+}
+
+void random_save_seed(void) {
+    HANDLE seedf;
+
+    if (!seedpath[0])
+	get_seedpath();
+
+    seedf = CreateFile(seedpath, GENERIC_WRITE, 0,
+		       NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+
+    if (seedf) {
+	int len;
+	DWORD lenwritten;
+	void *data;
+
+	random_get_savedata(&data, &len);
+	WriteFile(seedf, data, len, &lenwritten, NULL);
+	CloseHandle(seedf);
+    }
+}
+
+/*
+ * 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));
+
+    if (GetSystemPowerStatus(&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));
+}