Question

I am using Delphi to remotely read and write the registry of a remote machine. This works when my account on my machine has admin access to the remote machine.

However, I’d like to be able to specify a username / pwd when connecting to read the registry so I can connect with alternate credentials.

With the file-system I called the following (with the username and password) and was able to establish a connection to the remote system and perform filesystem related functions. However, this does not appear to work with the registry.

var
  netResource       : TNetResource;
begin

  FillChar(netResource, SizeOf(netResource), 0);
  netResource.dwScope := RESOURCE_GLOBALNET;
  netResource.dwType := RESOURCETYPE_DISK;
  netResource.dwDisplayType := RESOURCEDISPLAYTYPE_SHARE;
  netResource.dwUsage := RESOURCEUSAGE_CONNECTABLE;
  netResource.lpRemoteName := PChar('\\192.168.1.105\IPC$');

  WNetAddConnection2(netResource, PChar(password), PChar(username), 0);
end;

…

And here is the example of the function I’d like to be able to call, but specify the credentials with access to the remote machine:

procedure TForm1.SetWallpaperKey() ;
var
   reg:TRegistry;
begin
   reg:=TRegistry.Create;

   with reg do begin
    try
     if RegistryConnect('192.168.1.105') then
       if OpenKey('\Control Panel\desktop', False) then begin
       //change wallpaper and tile it
        reg.WriteString ('Wallpaper','c:\windows\CIRCLES.bmp') ;
        reg.WriteString ('TileWallpaper','1') ;
        //disable screen saver//('0'=disable, '1'=enable)
        reg.WriteString('ScreenSaveActive','0') ;
       end
    finally
      reg.Free;
    end;
   end;
end;

Answer 1

Mick , i can’t resist give you a WMI solution for you problem 😉 , the wmi have a class called StdRegProv which allow you to access the registry in local and remote machines. A key point is the namespace where the class is located, that depends of the version of windows installed in the remote machine. so for Windows Server 2003, Windows XP, Windows 2000, Windows NT 4.0, and Windows Me/98/95 the StdRegProv class is available in the root\default namespace and for others versions like windows Vista/7 the namespace is root\CIMV2.

Now to configure the credentials to access the registry, you must set these values in the SWbemLocator.ConnectServer method in this way :

FSWbemLocator.ConnectServer(Server, 'root\default', User, Pass);

Another impor point is which this class just exposes methods to access the registry not properties, so you cannot use a wmi query, instead you must execute wmi methods.

check the next samples to see how it works.

checking if you have permissions over a key

uses
  Windows,
  SysUtils,
  ActiveX,
  ComObj;

// The CheckAccess method verifies that the user possesses the specified
// permissions. The method returns a uint32 which is 0 if successful or some other
// value if any other error occurred.

procedure  Invoke_StdRegProv_CheckAccess;
const
  Server = '192.168.52.128';
  User   = 'Administrator';
  Pass   = 'password';
var
  FSWbemLocator   : OLEVariant;
  FWMIService     : OLEVariant;
  FWbemObjectSet  : OLEVariant;
  FInParams       : OLEVariant;
  FOutParams      : OLEVariant;
begin
  FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
  //http://msdn.microsoft.com/en-us/library/aa393664%28v=vs.85%29.aspx
  //StdRegProv is preinstalled in the WMI namespaces root\default and root\cimv2.
  //Windows Server 2003, Windows XP, Windows 2000, Windows NT 4.0, and Windows Me/98/95:  StdRegProv is available only in root\default namespace.
  FWMIService   := FSWbemLocator.ConnectServer(Server, 'root\default', User, Pass);
  //For Windows Vista or Windows 7 you must use the  root\CIMV2 namespace
  //FWMIService   := FSWbemLocator.ConnectServer(Server, 'root\CIMV2', User, Pass);
  FWbemObjectSet:= FWMIService.Get('StdRegProv');
  FInParams     := FWbemObjectSet.Methods_.Item('CheckAccess').InParameters.SpawnInstance_();
  FInParams.hDefKey:=HKEY_LOCAL_MACHINE;
  FInParams.sSubKeyName:='SYSTEM\CurrentControlSet';
  FInParams.uRequired:=KEY_QUERY_VALUE;

  FOutParams    := FWMIService.ExecMethod('StdRegProv', 'CheckAccess', FInParams);
  Writeln(Format('bGranted              %s',[FOutParams.bGranted]));
  Writeln(Format('ReturnValue           %s',[FOutParams.ReturnValue]));
end;

reading a string value

// The GetStringValue method returns the data value for a named value whose data 
// type is REG_SZ. 
procedure  Invoke_StdRegProv_GetStringValue;
const
  Server = '192.168.52.128';
  User   = 'Administrator';
  Pass   = 'password';
var
  FSWbemLocator   : OLEVariant;
  FWMIService     : OLEVariant;
  FWbemObjectSet  : OLEVariant;
  FInParams       : OLEVariant;
  FOutParams      : OLEVariant;
begin
  FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
  //http://msdn.microsoft.com/en-us/library/aa393664%28v=vs.85%29.aspx
  //StdRegProv is preinstalled in the WMI namespaces root\default and root\cimv2.
  //Windows Server 2003, Windows XP, Windows 2000, Windows NT 4.0, and Windows Me/98/95:  StdRegProv is available only in root\default namespace.
  FWMIService   := FSWbemLocator.ConnectServer(Server, 'root\default', User, Pass);
  //For Windows Vista or Windows 7 you must use the  root\CIMV2 namespace
  //FWMIService   := FSWbemLocator.ConnectServer(Server, 'root\CIMV2', User, Pass);
  FWbemObjectSet:= FWMIService.Get('StdRegProv');
  FInParams     := FWbemObjectSet.Methods_.Item('GetStringValue').InParameters.SpawnInstance_();
  FInParams.hDefKey:=HKEY_LOCAL_MACHINE;
  FInParams.sSubKeyName:='SOFTWARE\Borland\Delphi\5.0';
  FInParams.sValueName:='App';

  FOutParams    := FWMIService.ExecMethod('StdRegProv', 'GetStringValue', FInParams);
  Writeln(Format('sValue                %s',[FOutParams.sValue]));
  Writeln(Format('ReturnValue           %s',[FOutParams.ReturnValue]));
end;

writing a string value

// The SetStringValue method sets the data value for a named value whose data type 
// is REG_SZ.
procedure  Invoke_StdRegProv_SetStringValue;
const
  Server = '192.168.52.128';
  User   = 'Administrator';
  Pass   = 'password';
var
  FSWbemLocator   : OLEVariant;
  FWMIService     : OLEVariant;
  FWbemObjectSet  : OLEVariant;
  FInParams       : OLEVariant;
  FOutParams      : OLEVariant;
begin
  FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
  FWMIService   := FSWbemLocator.ConnectServer(Server, 'root\default', User, Pass);
  FWbemObjectSet:= FWMIService.Get('StdRegProv');
  FInParams     := FWbemObjectSet.Methods_.Item('SetStringValue').InParameters.SpawnInstance_();
  FInParams.hDefKey:=HKEY_LOCAL_MACHINE;
  FInParams.sSubKeyName:='SOFTWARE\Borland\Delphi\5.0';
  FInParams.sValueName:='Dummy';
  FInParams.sValue:='ADummyValue';

  FOutParams    := FWMIService.ExecMethod('StdRegProv', 'SetStringValue', FInParams);
  Writeln(Format('ReturnValue           %s',[FOutParams.ReturnValue]));
end;

For more options you must check the documentation about this class.

I hope this help you.