Pascal (Lazarus/Delphi)

Socket TLS Mutual Authentication (Client-Side Certificate)

See more Socket/SSL/TLS Examples

This example demonstrates how to provide a client-side certificate, also known as "two-way authentication" or "mutual authentication" for servers that require a client certificate. 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.Socket;

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

procedure RunDemo;
var
  success: Boolean;
  sock: TSocket;
  bTls: Boolean;
  port: Integer;
  maxWaitMs: Integer;

begin
  success := False;

  //  This example assumes the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  sock := TSocket.Create;

  //  Set the certificate to be used for mutual TLS authentication
  //  (i.e. sets the client-side certificate for two-way TLS authentication)
  success := sock.SetSslClientCertPfx('/home/bob/pfxFiles/myClientSideCertWithPrivateKey.pfx','pfxPassword');
  if (success <> True) then
    begin
      WriteLn(sock.LastErrorText);
      Exit;
    end;

  //  Note: The certificate used for the client-side of TLS mutual authentication
  //  must have the associated private key available. (.pfx/.p12 files typically store both
  //  the certificate and associated private key.)

  //  Establish the connection using the socket object (with client certificate authentication).
  bTls := True;
  port := 443;
  maxWaitMs := 5000;
  success := sock.Connect('www.example.com',port,bTls,maxWaitMs);
  if (success <> True) then
    begin
      WriteLn('Connect Failure Error Code: ' + sock.ConnectFailReason);
      WriteLn(sock.LastErrorText);
      Exit;
    end;

  //  At this point, the Socket object is connected and authenticated using the client-side cert

  //  ...
  //  ...


  sock.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.