(Delphi DLL) Load .crl, Convert to XML, Get Revoked Serial Numbers and Dates

Load a binary .crl file (Certificate Revocation List), converts to XML, and then gets the revoked certificate serial numbers and revocation dates.

Note: This example requires Chilkat v9.5.0.77 or greater.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Xml, Asn, BinData, CkDateTime;

...

procedure TForm1.Button1Click(Sender: TObject);
var
bdCrl: HCkBinData;
success: Boolean;
asn: HCkAsn;
xml: HCkXml;
i: Integer;
count_i: Integer;
tagPath: PWideChar;
j: Integer;
count_j: Integer;
k: Integer;
count_k: Integer;
revokedCertSerialHex: PWideChar;
dateRevoked: PWideChar;
dt: HCkDateTime;

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

// Load a binary .crl file.
bdCrl := CkBinData_Create();
success := CkBinData_LoadFile(bdCrl,'qa_data/crl/ca1.crl');
if (success <> True) then
  begin
    Memo1.Lines.Add('Failed to load CRL file.');
    Exit;
  end;

asn := CkAsn_Create();
success := CkAsn_LoadBd(asn,bdCrl);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkAsn__lastErrorText(asn));
    Exit;
  end;

// Convert ASN.1 to XML and load into xml and re-emit for pretty printing..
xml := CkXml_Create();
CkXml_LoadXml(xml,CkAsn__asnToXml(asn));
success := CkXml_SaveXml(xml,'qa_output/crl.xml');

// Use this online tool to generate parsing code from CRL XML: 
// Generate Parsing Code from XML

// Here's code to parse the XML.  This code was generated by the above tool,
// and then we modified it by removing unneeded code and changing some names

dt := CkDateTime_Create();

i := 0;
count_i := CkXml_NumChildrenHavingTag(xml,'sequence');
while i < count_i do
  begin
    CkXml_putI(xml,i);

    j := 0;
    count_j := CkXml_NumChildrenHavingTag(xml,'sequence[i]|sequence');
    while j < count_j do
      begin
        CkXml_putJ(xml,j);

        k := 0;
        count_k := CkXml_NumChildrenHavingTag(xml,'sequence[i]|sequence[j]|sequence');
        while k < count_k do
          begin
            CkXml_putK(xml,k);

            // Get the revoked certificate's serial number in uppercase hex.
            revokedCertSerialHex := CkXml__getChildContent(xml,'sequence[i]|sequence[j]|sequence[k]|int');
            Memo1.Lines.Add('serial number: ' + revokedCertSerialHex);

            // Get the date/time revoked.  It will be a string formatted as "YYMMDDhhmmssZ", such as "181023093028Z"
            dateRevoked := CkXml__getChildContent(xml,'sequence[i]|sequence[j]|sequence[k]|utctime');

            // Starting in Chilkat v9.5.0.77, date/time strings formatted as YYMMDDhhmmssZ can be parsed as follows:
            CkDateTime_SetFromTimestamp(dt,dateRevoked);
            Memo1.Lines.Add('date revoked: ' + CkDateTime__getAsRfc822(dt,False));

            k := k + 1;
          end;

        j := j + 1;
      end;

    i := i + 1;
  end;

CkBinData_Dispose(bdCrl);
CkAsn_Dispose(asn);
CkXml_Dispose(xml);
CkDateTime_Dispose(dt);

end;