Delphi ActiveX

Combine Timestamp Reply and Content File into a TimeStampData

See more ASN.1 Examples

Demonstrates how to combine a timestamp reply (RFC 3161) with a data file (any type of file) to create a TimeStampData structure (RFC 5544). Delphi ActiveX

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
bdTsr: TChilkatBinData;
asnTsr: TChilkatAsn;
xmlTsr: TChilkatXml;
bdContent: TChilkatBinData;
xml: TChilkatXml;
xContext: IChilkatXml;
tsd: TChilkatAsn;
tsdBase64: WideString;

begin
success := 0;

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

// Also see this example:
// Send a TimeStamp Request to a TimeStamp Authority and get the Response

// Load a timestamp reply file
bdTsr := TChilkatBinData.Create(Self);
success := bdTsr.LoadFile('qa_data/tsd/sample.tsr');
if (success <> 1) then
  begin
    Memo1.Lines.Add('Failed to load timestamp reply file.');
    Exit;
  end;

// Load the tsr into an ASN.1 object.
asnTsr := TChilkatAsn.Create(Self);
success := asnTsr.LoadEncoded(bdTsr.GetEncoded('base64'),'base64');
if (success <> 1) then
  begin
    Memo1.Lines.Add(asnTsr.LastErrorText);
    Exit;
  end;

// Get the timestamp reply as XML.
xmlTsr := TChilkatXml.Create(Self);
xmlTsr.LoadXml(asnTsr.AsnToXml());

// The timestamp reply XML begins like this:
// We'll want to remove the 1st "sequence" subtree.

//     <?xml version="1.0" encoding="utf-8"?>
//     <sequence>
//         <sequence>       <---- Remove this sub-tree.
//             <int>00</int>
//             <sequence>
//                 <utf8>Operation Okay</utf8>
//             </sequence>
//         </sequence>
//         <sequence>   
//             <oid>1.2.840.113549.1.7.2</oid>
//             <contextSpecific tag="0" constructed="1">
//             ...

// Remove the 1st sub-tree..
xmlTsr.RemoveChildByIndex(0);

// In this example, the data file we're combining with the timestamp into a timestampData is a .p7m.
// However, it can be any type of file (text or binary), it doesn't matter..
bdContent := TChilkatBinData.Create(Self);
success := bdContent.LoadFile('qa_data/tsd/sample.p7m');
if (success <> 1) then
  begin
    Memo1.Lines.Add('Failed to load content file.');
    Exit;
  end;

// Begin building the TimeStampData.  
// We'll build as XML and then convert to ASN.1
xml := TChilkatXml.Create(Self);
xml.Tag := 'sequence';
xml.UpdateChildContent('oid','1.2.840.113549.1.9.16.1.31');
xml.UpdateAttrAt('contextSpecific',1,'tag','0');
xml.UpdateAttrAt('contextSpecific',1,'constructed','1');
xml.UpdateChildContent('contextSpecific|sequence|int','01');
xml.UpdateChildContent('contextSpecific|sequence|octets',bdContent.GetEncoded('base64'));
xml.UpdateAttrAt('contextSpecific|sequence|contextSpecific',1,'tag','0');
xml.UpdateAttrAt('contextSpecific|sequence|contextSpecific',1,'constructed','1');

xContext := xml.GetChildWithTag('contextSpecific|sequence|contextSpecific');
xContext.AddChildTree(xmlTsr.ControlInterface);

// Convert the XML to ASN.1
tsd := TChilkatAsn.Create(Self);
tsd.LoadAsnXml(xml.GetXml());

// Write the timestamped data to a file.
success := tsd.WriteBinaryDer('qa_output/sample.tsd');

// Alternatively, get the tsd ASN.1 as base64..
tsdBase64 := tsd.GetEncodedDer('base64_mime');
Memo1.Lines.Add(tsdBase64);
end;