Problem - Kevin Tafuro

*pHwnd = 0;
return TRUE;
}
BOOL SpcGatherKeyboardEntropy(HINSTANCE hInstance, HWND hWndParent,
BYTE *pbOutput, DWORD cbOutput) {
MSG msg;
BOOL bResult = FALSE;
BYTE bLastScanCode = 0, *pbHashData = 0;
HWND hwndDlg;
DWORD cbHashData, dwByteCount = sizeof(DWORD), dwLastTime = 0;
double dEntropy = 0.0;
HCRYPTHASH hHash = 0;
HCRYPTPROV hProvider = 0;
SPC_KEYPRESS KeyPress;
if (!CryptAcquireContext(&hProvider, 0, MS_DEF_PROV, PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT)) goto done;
if (!CryptCreateHash(hProvider, CALG_SHA1, 0, 0, &hHash)) goto done;
if (!CryptGetHashParam(hHash, HP_HASHSIZE, (BYTE *)&cbHashData, &dwByteCount,
0)) goto done;
if (cbOutput > cbHashData) goto done;
if (!(pbHashData = (BYTE *)LocalAlloc(LMEM_FIXED, cbHashData))) goto done;
hwndDlg = CreateDialog(hInstance, MAKEINTRESOURCE(SPC_KEYBOARD_DLGID),
hWndParent, KeyboardEntropyProc);
if (hwndDlg) {
if (hWndParent) EnableWindow(hWndParent, FALSE);
SetWindowLong(hwndDlg, DWL_USER, (LONG)&hwndDlg);
SendDlgItemMessage(hwndDlg, SPC_PROGRESS_BARID, PBM_SETRANGE32, 0,
cbOutput * 8);
while (hwndDlg && GetMessage(&msg, 0, 0, 0) > 0) {
if ((msg.message = = WM_KEYDOWN || msg.message = = WM_KEYUP) &&
dEntropy < cbOutput * 8) {
KeyPress.bScanCode = ((msg.lParam >> 16) & 0x0000000F);
KeyPress.dwTickCount = GetTickCount( );
CryptHashData(hHash, (BYTE *)&KeyPress, sizeof(KeyPress), 0);
if (msg.message = = WM_KEYUP || (bLastScanCode != KeyPress.bScanCode &&
KeyPress.dwTickCount - dwLastTime > 100)) {
bLastScanCode = KeyPress.bScanCode;
dwLastTime = KeyPress.dwTickCount;
dEntropy += SPC_ENTROPY_PER_SAMPLE;
SendDlgItemMessage(hwndDlg, SPC_PROGRESS_BARID, PBM_SETPOS,
(WPARAM)dEntropy, 0);
if (dEntropy >= cbOutput * 8) {
EnableWindow(GetDlgItem(hwndDlg, IDOK), TRUE);
SetFocus(GetDlgItem(hwndDlg, IDOK));
MessageBeep(0xFFFFFFFF);
}
}
continue;
}
if (!IsDialogMessage(hwndDlg, &msg)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
636 | Chapter 11: Random Numbers
This is the Title of the Book, eMatter Edition
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