// --------------------------------------------------------------------------
// Module Name: UIHost.cpp
//
// Copyright (c) 1999-2000, Microsoft Corporation
//
// Class to handle the UI host for the logon process. This handles the IPC
// as well as the creation and monitoring of process death. The process is
// a restricted SYSTEM context process.
//
// History: 1999-09-14 vtan created
// 2000-02-01 vtan moved from Neptune to Whistler
// --------------------------------------------------------------------------
#include "StandardHeader.h"
#include "UIHost.h"
#include "RegistryResources.h"
#include "StatusCode.h"
#include "SystemSettings.h"
// --------------------------------------------------------------------------
// CUIHost::CUIHost
//
// Arguments: <none>
//
// Returns: <none>
//
// Purpose: Constructor for CUIHost. Determine UI host process. If none
// exists then indicate it.
//
// History: 1999-09-14 vtan created
// --------------------------------------------------------------------------
CUIHost::CUIHost (const TCHAR *pszCommandLine) :
CExternalProcess(),
_hwndArray(sizeof(HWND)),
_pBufferAddress(NULL)
{
ExpandCommandLine(pszCommandLine);
AdjustForDebugging();
}
// --------------------------------------------------------------------------
// CUIHost::~CUIHost
//
// Arguments: <none>
//
// Returns: <none>
//
// Purpose: Destructor for CUIHost.
//
// History: 1999-09-14 vtan created
// --------------------------------------------------------------------------
CUIHost::~CUIHost (void)
{
if (_pBufferAddress != NULL)
{
(BOOL)VirtualFreeEx(_hProcess, _pBufferAddress, 0, MEM_DECOMMIT);
_pBufferAddress = NULL;
}
}
// --------------------------------------------------------------------------
// CUIHost::WaitRequired
//
// Arguments: <none>
//
// Returns: bool
//
// Purpose: Returns whether a wait is required for the UI host. This is
// important when communication with the UI host is required or
// if the UI host is being debugged.
//
// History: 2000-10-05 vtan created
// --------------------------------------------------------------------------
bool CUIHost::WaitRequired (void) const
{
#ifdef DBG
return(IsBeingDebugged());
#else /* DBG */
return(false);
#endif /* DBG */
}
// --------------------------------------------------------------------------
// CUIHost::GetData
//
// Arguments: pUIHostProcessAddress = Address in the UI host.
// pLogonProcessAddress = Address in the logon process.
// iDataSize = Size of the data.
//
// Returns: NTSTATUS
//
// Purpose: Extracts the data from the UI host. This could be another
// process that we started or it could be in process if we
// failed to start the UI host. This function deals with it
// either way.
//
// History: 1999-08-24 vtan created
// 1999-09-14 vtan factored
// --------------------------------------------------------------------------
NTSTATUS CUIHost::GetData (const void *pUIHostProcessAddress, void *pLogonProcessAddress, int iDataSize) const
{
NTSTATUS status;
status = STATUS_SUCCESS;
if (_hProcess == NULL)
{
CopyMemory(pLogonProcessAddress, pUIHostProcessAddress, iDataSize);
}
else
{
if (ReadProcessMemory(_hProcess, pUIHostProcessAddress, pLogonProcessAddress, iDataSize, NULL) == FALSE)
{
status = CStatusCode::StatusCodeOfLastError();
}
}
return(status);
}
// --------------------------------------------------------------------------
// CUIHost::PutData
//
// Arguments: pUIHostProcessAddress = Address in the UI host.
// pLogonProcessAddress = Address in the logon process.
// iDataSize = Size of the data.
//
// Returns: NTSTATUS
//
// Purpose: Puts data into the UI host. This could be another process that
// we started or it could be in process if we failed to start the
// UI host. This function deals with it either way.
//
// History: 1999-08-24 vtan created
// 1999-09-14 vtan factored
// --------------------------------------------------------------------------
NTSTATUS CUIHost::PutData (void *pUIHostProcessAddress, const void *pLogonProcessAddress, int iDataSize) const
{
NTSTATUS status;
status = STATUS_SUCCESS;
if (_hProcess == NULL)
{
CopyMemory(pUIHostProcessAddress, pLogonProcessAddress, iDataSize);
}
else
{
if (WriteProcessMemory(_hProcess, pUIHostProcessAddress, const_cast<void*>(pLogonProcessAddress), iDataSize, NULL) == FALSE)
{
status = CStatusCode::StatusCodeOfLastError();
}
}
return(status);
}
// --------------------------------------------------------------------------
// CUIHost::Show
//
// Arguments: <none>
//
// Returns: NTSTATUS
//
// Purpose: Iterate the top level windows on this desktop and for any that
// correspond to the UI host - show them!
//
// History: 2000-03-08 vtan created
// --------------------------------------------------------------------------
NTSTATUS CUIHost::Show (void)
{
int i;
i = _hwndArray.GetCount();
if (i > 0)
{
for (--i; i >= 0; --i)
{
HWND hwnd;
if (NT_SUCCESS(_hwndArray.Get(&hwnd, i)) && (hwnd != NULL))
{
(BOOL)ShowWindow(hwnd, SW_SHOW);
}
TSTATUS(_hwndArray.Remove(i));
}
}
return(STATUS_SUCCESS);
}
// --------------------------------------------------------------------------
// CUIHost::Hide
//
// Arguments: <none>
//
// Returns: NTSTATUS
//
// Purpose: Iterate the top level windows on this desktop and for any that
// correspond to the UI host - hide them!
//
// History: 2000-03-08 vtan created
// --------------------------------------------------------------------------
NTSTATUS CUIHost::Hide (void)
{
NTSTATUS status;
status = STATUS_SUCCESS;
if (_hwndArray.GetCount() == 0)
{
if (EnumWindows(EnumWindowsProc, reinterpret_cast<LPARAM>(this)) == FALSE)
{
status = CStatusCode::StatusCodeOfLastError();
}
}
return(status);
}
// --------------------------------------------------------------------------
// CUIHost::IsHidden
//
// Arguments: <none>
//
// Returns: bool
//
// Purpose: Returns whether the UI host is currently hidden or not.
//
// History: 2000-07-05 vtan created
// --------------------------------------------------------------------------
bool CUIHost::IsHidden (void) const
{
return(_hwndArray.GetCount() != 0);
}
// --------------------------------------------------------------------------
// CUIHost::GetDataAddress
//
// Arguments: <none>
//
// Returns: void*
//
// Purpose: Returns the address of the buffer valid in the UI host process
// context.
//
// History: 2000-05-05 vtan created
// --------------------------------------------------------------------------
void* CUIHost::GetDataAddress (void) const
{
return(_pBufferAddress);
}
// --------------------------------------------------------------------------
// CUIHost::PutData
//
// Arguments: pvData = Pointer to data.
// dwDataSize = Size of data (in bytes).
//
// Returns: NTSTATUS
//
// Purpose: Writes the data to the UI host process at an allocated
// address. If the address has not been allocated then it's
// allocated and cached. It's released when this object goes
// out of scope.
//
// History: 2000-05-05 vtan created
// 2001-01-10 vtan changed to generic data placement
// --------------------------------------------------------------------------
NTSTATUS CUIHost::PutData (const void *pvData, DWORD dwDataSize)
{
NTSTATUS status;
if (_pBufferAddress == NULL)
{
_pBufferAddress = VirtualAllocEx(_hProcess,
0,
2048,
MEM_COMMIT,
PAGE_READWRITE);
}
if (_pBufferAddress != NULL)
{
ASSERTMSG(dwDataSize < 2048, "Impending kernel32!WriteProcessMemory failure in CUIHost::PutData");
if (WriteProcessMemory(_hProcess,
_pBufferAddress,
const_cast<void*>(pvData),
dwDataSize,
NULL) != FALSE)
{
status = STATUS_SUCCESS;
}
else
{
status = CStatusCode::StatusCodeOfLastError();
}
}
else
{
status = STATUS_NO_MEMORY;
}
return(status);
}
// --------------------------------------------------------------------------
// CUIHost::PutString
//
// Arguments: pszString = String to put into UI host process.
//
// Returns: NTSTATUS
//
// Purpose: Writes the string to the UI host process at an allocated
// address. If the address has not been allocated then it's
// allocated and cached. It's released when this object goes
// out of scope.
//
// History: 2000-05-05 vtan created
// --------------------------------------------------------------------------
NTSTATUS CUIHost::PutString (const WCHAR *pszString)
{
ASSERTMSG(lstrlenW(pszString) < 256, "Too many characters in string passed to CUIHost::PutString");
return(PutData(pszString, (lstrlenW(pszString) + sizeof('\0')) * sizeof(WCHAR)));
}
// --------------------------------------------------------------------------
// CUIHost::NotifyNoProcess
//
// Arguments: <none>
//
// Returns: NTSTATUS
//
// Purpose: Clears the string address associated with the process that
// has now died.
//
// History: 2001-01-09 vtan created
// --------------------------------------------------------------------------
void CUIHost::NotifyNoProcess (void)
{
_pBufferAddress = NULL;
}
// --------------------------------------------------------------------------
// CUIHost::ExpandCommandLine
//
// Arguments: pszCommandLine = Command line of UI host
//
// Returns: <none>
//
// Purpose: Find out which UI host we should use for the logon UI. This
// is specified in registry at the moment but should be a less
// accessible place to prevent tampering. An error is returned
// if no host is specified.
//
// History: 1999-08-24 vtan created
// 1999-09-14 vtan factored
// --------------------------------------------------------------------------
void CUIHost::ExpandCommandLine (const TCHAR *pszCommandLine)
{
if (ExpandEnvironmentStrings(pszCommandLine, _szCommandLine, ARRAYSIZE(_szCommandLine)) == 0)
{
lstrcpy(_szCommandLine, pszCommandLine);
}
}
// --------------------------------------------------------------------------
// CUIHost::EnumWindowsProc
//
// Arguments: hwnd = HWND from user32
// lParam = this object.
//
// Returns: BOOL
//
// Purpose: Determines if the given HWND in the iteration belongs to the
// UI host process.
//
// History: 2000-03-08 vtan created
// --------------------------------------------------------------------------
BOOL CALLBACK CUIHost::EnumWindowsProc (HWND hwnd, LPARAM lParam)
{
DWORD dwThreadID, dwProcessID;
CUIHost *pUIHost;
pUIHost = reinterpret_cast<CUIHost*>(lParam);
dwThreadID = GetWindowThreadProcessId(hwnd, &dwProcessID);
if ((dwProcessID == pUIHost->_dwProcessID) && IsWindowVisible(hwnd))
{
(NTSTATUS)pUIHost->_hwndArray.Add(&hwnd);
(BOOL)ShowWindow(hwnd, SW_HIDE);
}
return(TRUE);
}