Windows firewall rule for XP

Question

How to programmatically add an application or port to Windows Firewall on Windows XP?

Answer 1

Try this code extracted from our open source SQlite3UI.pas unit:

function GetXPFirewall(var fwMgr, profile: OleVariant): boolean;
begin
  Result := (Win32Platform=VER_PLATFORM_WIN32_NT) and
    (Win32MajorVersion>5) or ((Win32MajorVersion=5) and (Win32MinorVersion>0));
  if result then // need Windows XP at least
  try 
    fwMgr := CreateOleObject('HNetCfg.FwMgr');
    profile := fwMgr.LocalPolicy.CurrentProfile;
  except
    on E: Exception do
      result := false;
  end;
end;

const
  NET_FW_PROFILE_DOMAIN = 0;
  NET_FW_PROFILE_STANDARD = 1;
  NET_FW_IP_VERSION_ANY = 2;
  NET_FW_IP_PROTOCOL_UDP = 17;
  NET_FW_IP_PROTOCOL_TCP = 6;
  NET_FW_SCOPE_ALL = 0;
  NET_FW_SCOPE_LOCAL_SUBNET = 1;

procedure AddApplicationToXPFirewall(const EntryName, ApplicationPathAndExe: string);
var fwMgr, profile, app: OleVariant;
begin
  if GetXPFirewall(fwMgr,profile) then
  try
    if profile.FirewallEnabled then begin
      app := CreateOLEObject('HNetCfg.FwAuthorizedApplication');
      try
        app.ProcessImageFileName := ApplicationPathAndExe;
        app.Name := EntryName;
        app.Scope := NET_FW_SCOPE_ALL;
        app.IpVersion := NET_FW_IP_VERSION_ANY;
        app.Enabled :=true;
        profile.AuthorizedApplications.Add(app);
      finally
        app := varNull;
      end;
    end;
  finally
    profile := varNull;
    fwMgr := varNull;
  end;
end;

procedure AddPortToXPFirewall(const EntryName: string; PortNumber: cardinal);
var fwMgr, profile, port: OleVariant;
begin
  if GetXPFirewall(fwMgr,profile) then
  try
    if profile.FirewallEnabled then begin
      port := CreateOLEObject('HNetCfg.FWOpenPort');
      port.Name := EntryName;
      port.Protocol := NET_FW_IP_PROTOCOL_TCP;
      port.Port := PortNumber;
      port.Scope := NET_FW_SCOPE_ALL;
      port.Enabled := true;
      profile.GloballyOpenPorts.Add(port);
    end;
  finally
    port := varNull;
    profile := varNull;
    fwMgr := varNull;
  end;
end;

It will allow you to add an application or a port to the XP firewall. Should work from Delphi 6 up to XE.