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Pascal (Lazarus/Delphi)

Set a TLS Client Certificate from a Cert Object

See more Socket/SSL/TLS Examples

Demonstrates Socket.SetSslClientCert, which configures a certificate as the client certificate for subsequent TLS connections. The certificate must have access to its private key.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

Background. Configure the client certificate before connecting. Use client certificates only when the server requests or requires client-certificate authentication (mutual TLS).

Chilkat Pascal (Lazarus/Delphi) Downloads

Pascal (Lazarus/Delphi)
program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Cert,
  Chilkat.Socket;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  socket: TSocket;
  pfxPassword: string;
  cert: TCert;
  bTls: Boolean;
  maxWaitMs: Integer;

begin
  success := False;

  socket := TSocket.Create;

  //  The file path is relative to the application's current working directory.  An absolute path
  //  may also be used.  Supply the path appropriate to your own environment.
  //  The PFX password should come from a secure source rather than being hard-coded.
  pfxPassword := 'myPfxPassword';
  cert := TCert.Create;
  success := cert.LoadPfxFile('qa_data/client.pfx',pfxPassword);
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  //  Configure the client certificate before connecting.  Use this only when the server requests or
  //  requires client-certificate authentication (mutual TLS).
  success := socket.SetSslClientCert(cert);
  if (success = False) then
    begin
      WriteLn(socket.LastErrorText);
      Exit;
    end;

  bTls := True;
  maxWaitMs := 5000;
  success := socket.Connect('example.com',5000,bTls,maxWaitMs);
  if (success = False) then
    begin
      WriteLn(socket.LastErrorText);
      Exit;
    end;
  WriteLn('Connected with mutual TLS.');


  socket.Free;
  cert.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.