Pascal (Lazarus/Delphi)

Verify XML Digital Signature

See more XML Digital Signatures Examples

Verifies XML signatures in an XML file. 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.XmlDSig,
  Chilkat.StringBuilder;

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

procedure RunDemo;
var
  success: Boolean;
  sbXml: TStringBuilder;
  dsig: TXmlDSig;
  i: Integer;
  bVerifyReferenceDigests: Boolean;
  bVerified: Boolean;

begin
  success := False;

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

  sbXml := TStringBuilder.Create;
  success := sbXml.LoadFile('qa_data/xml_dsig_verify/csioz_sample.xml','utf-8');
  if (success <> True) then
    begin
      WriteLn('Failed to load XML file.');
      Exit;
    end;

  dsig := TXmlDSig.Create;

  //  First load the XML containing the signatures to be verified.
  success := dsig.LoadSignatureSb(sbXml);
  if (success <> True) then
    begin
      WriteLn(dsig.LastErrorText);
      Exit;
    end;

  //  It's possible that an XML document can contain multiple signatures.
  //  Each can be verified as follows:
  i := 0;
  while i < dsig.NumSignatures do
    begin
      //  Select the Nth signature by setting the Selector property.
      dsig.Selector := i;

      //  The bVerifyReferenceDigests argument determines if we want
      //  to also verify each reference digest.  If set to False,
      //  then only the SignedInfo part of the Signature is verified.
      bVerifyReferenceDigests := True;
      bVerified := dsig.VerifySignature(bVerifyReferenceDigests);
      WriteLn('Signature ' + i + 1 + ' verified = ' + bVerified);

      i := i + 1;
    end;



  sbXml.Free;
  dsig.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.