/*
 Copyright (c) 2007-2008 TrueCrypt Foundation. All rights reserved.

 Governed by the TrueCrypt License 2.5 the full text of which is contained
 in the file License.txt included in TrueCrypt binary and source code
 distribution packages.
*/

#include <atlcomcli.h>
#include <atlconv.h>
#include <comutil.h>
#include <windows.h>
#include "BaseCom.h"
#include "BootEncryption.h"
#include "Dlgcode.h"
#include "Registry.h"

using namespace TrueCrypt;

HRESULT CreateElevatedComObject (HWND hwnd, REFGUID guid, REFIID iid, void **ppv)
{
    WCHAR monikerName[1024];
    WCHAR clsid[1024];
    BIND_OPTS3 bo;

    StringFromGUID2 (guid, clsid, sizeof (clsid) / 2);
	swprintf_s (monikerName, sizeof (monikerName) / 2, L"Elevation:Administrator!new:%s", clsid);

    memset (&bo, 0, sizeof (bo));
    bo.cbStruct = sizeof (bo);
    bo.hwnd = hwnd;
    bo.dwClassContext = CLSCTX_LOCAL_SERVER;

	// Prevent the GUI from being half-rendered when the UAC prompt "freezes" it
	MSG paintMsg;
	int MsgCounter = 5000;	// Avoid endless processing of paint messages
	while (PeekMessage (&paintMsg, hwnd, 0, 0, PM_REMOVE | PM_QS_PAINT) != 0 && --MsgCounter > 0)
	{
		DispatchMessage (&paintMsg);
	}

    return CoGetObject (monikerName, &bo, iid, ppv);
}


BOOL ComGetInstanceBase (HWND hWnd, REFCLSID clsid, REFIID iid, void **tcServer)
{
	BOOL r;

	if (IsUacSupported ())
		r = CreateElevatedComObject (hWnd, clsid, iid, tcServer) == S_OK;
	else
		r = CoCreateInstance (clsid, NULL, CLSCTX_LOCAL_SERVER, iid, tcServer) == S_OK;

	if (!r)
		Error ("UAC_INIT_ERROR");

	return r;
}


DWORD BaseCom::CallDriver (DWORD ioctl, BSTR input, BSTR *output)
{
	try
	{
		BootEncryption bootEnc (NULL);
		bootEnc.CallDriver (ioctl,
			(BYTE *) input, !(BYTE *) input ? 0 : ((DWORD *) ((BYTE *) input))[-1],
			(BYTE *) *output, !(BYTE *) *output ? 0 : ((DWORD *) ((BYTE *) *output))[-1]);
	}
	catch (SystemException &)
	{
		return GetLastError();
	}
	catch (Exception &e)
	{
		e.Show (NULL);
		return ERROR_EXCEPTION_IN_SERVICE;
	}
	catch (...)
	{
		return ERROR_EXCEPTION_IN_SERVICE;
	}

	return ERROR_SUCCESS;
}


BOOL BaseCom::IsPagingFileActive ()
{
	return ::IsPagingFileActive();
}


DWORD BaseCom::ReadWriteFile (BOOL write, BOOL device, BSTR filePath, BSTR *bufferBstr, unsigned __int64 offset, unsigned __int32 size, DWORD *sizeDone)
{
	USES_CONVERSION;

	try
	{
		auto_ptr <File> file (device ? new Device (string (CW2A (filePath)), !write) : new File (string (CW2A (filePath)), !write));
		file->SeekAt (offset);

		if (write)
		{
			file->Write ((BYTE *) *bufferBstr, size);
			*sizeDone = size;
		}
		else
		{
			*sizeDone = file->Read ((BYTE *) *bufferBstr, size);
		}
	}
	catch (SystemException &)
	{
		return GetLastError();
	}
	catch (Exception &e)
	{
		e.Show (NULL);
		return ERROR_EXCEPTION_IN_SERVICE;
	}
	catch (...)
	{
		return ERROR_EXCEPTION_IN_SERVICE;
	}

	return ERROR_SUCCESS;
}


DWORD BaseCom::RegisterFilterDriver (BOOL registerDriver, BOOL volumeClass)
{
	try
	{
		BootEncryption bootEnc (NULL);
		bootEnc.RegisterFilterDriver (registerDriver ? true : false, volumeClass ? true : false);
	}
	catch (SystemException &)
	{
		return GetLastError();
	}
	catch (Exception &e)
	{
		e.Show (NULL);
		return ERROR_EXCEPTION_IN_SERVICE;
	}
	catch (...)
	{
		return ERROR_EXCEPTION_IN_SERVICE;
	}

	return ERROR_SUCCESS;
}


DWORD BaseCom::SetDriverServiceStartType (DWORD startType)
{
	try
	{
		BootEncryption bootEnc (NULL);
		bootEnc.SetDriverServiceStartType (startType);
	}
	catch (SystemException &)
	{
		return GetLastError();
	}
	catch (Exception &e)
	{
		e.Show (NULL);
		return ERROR_EXCEPTION_IN_SERVICE;
	}
	catch (...)
	{
		return ERROR_EXCEPTION_IN_SERVICE;
	}

	return ERROR_SUCCESS;
}


DWORD BaseCom::WriteLocalMachineRegistryDwordValue (BSTR keyPath, BSTR valueName, DWORD value)
{
	USES_CONVERSION;
	if (!::WriteLocalMachineRegistryDword (CW2A (keyPath), CW2A (valueName), value))
		return GetLastError();

	return ERROR_SUCCESS;
}