(Delphi ActiveX) Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

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
mailman: TChilkatMailMan;
email: TChilkatEmail;
success: Integer;
certStore: TChilkatCertStore;
cert: IChilkatCert;
cert2: TChilkatCert;

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

// The mailman object is used for sending and receiving email.
mailman := TChilkatMailMan.Create(Self);

// Set the SMTP server.
mailman.SmtpHost := 'smtp.mymailserver.com';

// Create a new email object
email := TChilkatEmail.Create(Self);

email.Subject := 'This email is signed';
email.Body := 'This is a digitally signed mail';
email.From := 'Chilkat Admin <admin@chilkatsoft.com>';
success := email.AddTo('Chilkat Support','support@chilkatsoft.com');

// Indicate that the email should be sent signed.
email.SendSigned := 1;

// Load a PFX file into a certificate store object.
// Then locate the certificate matching the  sender's email address,
// and use it for signing.
// (a PFX file may contain more than one certificate.)
certStore := TChilkatCertStore.Create(Self);
// The 1st argument is the path of the PFX file, the 2nd arg is the 
// PFX file's password:
success := certStore.LoadPfxFile('/pfx_files/chilkatsoft_secret.pfx','secret');
if (success <> 1) then
  begin
    Memo1.Lines.Add(certStore.LastErrorText);
    Exit;
  end;

cert := certStore.FindCertBySubjectE('admin@chilkatsoft.com');
if (certStore.LastMethodSuccess = 0) then
  begin
    Memo1.Lines.Add(certStore.LastErrorText);
    Exit;
  end;

// Alternatively, if a PFX file is known to contain a single certificate,
// you may load it directly into a Chilkat certificate object.
// This snippet of source code shows how:
cert2 := TChilkatCert.Create(Self);
// The 1st argument is the filename, the 2nd arg is the 
// PFX file's password:
success := cert2.LoadPfxFile('/pfx_files/chilkatsoft_secret.pfx','secret');
if (success <> 1) then
  begin
    Memo1.Lines.Add(cert2.LastErrorText);

    Exit;
  end;

// This example will use the cert from the certStore...
success := email.SetSigningCert(cert);

// Signed email can be sent in two different ways.  
// In a multipart/signed email, the signature is attached as a separate MIME part.
// In an opaque email (signedData) the content of the email is encapsulated within the signature
// and the email is sent as "application/pkcs7-mime". 
// Either should be fine, but some receiving systems might require one or the other..
mailman.OpaqueSigning := 0;

// Send a signed email.
success := mailman.SendEmail(email.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
  end
else
  begin
    // The LastErrorText property provides information
    // even when successful.
    Memo1.Lines.Add(mailman.LastErrorText);
    Memo1.Lines.Add('Mail Sent!');
  end;
end;