(Delphi DLL) Get Certificate User Principal Name (UPN)

See more Certificates Examples

Demonstrates how to get a certificate's UPN from the SAN (Subject Alternative Name). Most certificates do not have a UPN. This example only applies to those certificates that have a User Principal Name.

Note: This example requires Chilkat v9.5.0.90 or greater due to fixes made in getting the UPN from the SAN.

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, Cert, Xml;

...

procedure TForm1.Button1Click(Sender: TObject);
var
cert: HCkCert;
success: Boolean;
xml: HCkXml;
upn: PWideChar;

begin
cert := CkCert_Create();

success := CkCert_LoadFromFile(cert,'qa_data/certs/sample.cer');
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

xml := CkXml_Create();
CkXml_LoadXml(xml,CkCert__subjectAlternativeName(cert));
Memo1.Lines.Add(CkXml__getXml(xml));

// A certificate with a User Principal Name in the SAN might have this:

// <SubjectAltName>
//     <rfc822Name>joe@example.com</rfc822Name>
//     <name type="oid" oid="1.3.6.1.4.1.311.20.2.3">joe@example.com</name>
// </SubjectAltName>

// The OID 1.3.6.1.4.1.311.20.2.3 is for the User Principal Name.
upn := CkXml__chilkatPath(xml,'/A/name,oid,1.3.6.1.4.1.311.20.2.3|*');
if (CkXml_getLastMethodSuccess(xml) = False) then
  begin
    Memo1.Lines.Add('No user principle name.');
  end
else
  begin
    Memo1.Lines.Add('User Principle Name = ' + upn);
  end;

CkCert_Dispose(cert);
CkXml_Dispose(xml);

end;