(Delphi ActiveX) Find Certificate by Email Address

See more Cert Store Examples

In an X.509 certificate, an email address can typically be located in two places:

1. RFC822 Name (Subject Alternative Name extension) -
   • The certificate may include an email address in the Subject Alternative Name (SAN) extension under the RFC822 Name field. This is a modern and preferred method because it allows for flexibility and alignment with security best practices.
   • To find it, Chilkat inspects the SAN extension in the certificate details.
2. Subject (Common Name or Email Address attribute) -
   • Older certificates may store the email address directly in the Subject field, typically under the Email Address attribute ("emailAddress") or, less commonly, the Common Name (CN).
   • This method is less preferred in modern standards but can still be encountered in legacy implementations. Chilkat also searches here for the email address.

Note: Requires Chilkat v10.1.2 or later.

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

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
certStore: TChilkatCertStore;
readOnly: Integer;
success: Integer;
json: TChilkatJsonObject;
email_address: WideString;
cert: TChilkatCert;

begin
certStore := TChilkatCertStore.Create(Self);

// This opens the Current User certificate store on Windows,
// On MacOS and iOS it opens the default Keychain.
readOnly := 0;
success := certStore.OpenCurrentUserStore(readOnly);
if (success = 0) then
  begin
    Memo1.Lines.Add(certStore.LastErrorText);
    Exit;
  end;

// Find the certificate having the specified email address in either the RFC822 Name or in the Subject.
json := TChilkatJsonObject.Create(Self);
email_address := 'joe@example.com';
json.UpdateString('email',email_address);

cert := TChilkatCert.Create(Self);
success := certStore.FindCert(json.ControlInterface,cert.ControlInterface);
if (success = 1) then
  begin
    // Show the full distinguished name of the certificate.
    Memo1.Lines.Add('Found: ' + cert.SubjectDN);
  end
else
  begin
    Memo1.Lines.Add('Not found.');
  end;
end;