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Pascal (Lazarus/Delphi)

Get the Server Certificate from a TLS Connection

See more Socket/SSL/TLS Examples

Demonstrates Socket.GetServerCert, which copies the certificate presented by the remote TLS server into a Cert object for inspection.

Background. The method returns false when the socket is not connected, is not using TLS, or no server certificate is available. Inspecting the certificate lets an application validate the server's identity.

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;
  bTls: Boolean;
  maxWaitMs: Integer;
  cert: TCert;

begin
  success := False;

  socket := TSocket.Create;

  //  Connect to the server using TLS.
  bTls := True;
  maxWaitMs := 5000;
  success := socket.Connect('example.com',5000,bTls,maxWaitMs);
  if (success = False) then
    begin
      WriteLn(socket.LastErrorText);
      Exit;
    end;

  //  Copy the certificate presented by the remote TLS server, then inspect it.  This can be used to
  //  validate the server's identity.
  cert := TCert.Create;
  success := socket.GetServerCert(cert);
  if (success = False) then
    begin
      WriteLn(socket.LastErrorText);
      Exit;
    end;
  WriteLn('Server certificate subject: ' + cert.SubjectCN);
  WriteLn('Issued by: ' + cert.IssuerCN);


  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.