Delphi ActiveX

Load .eml and Decrypt (smime.p7m)

Loads an encrypted email from a .eml file and decrypts using certificate w/ private key found in a .p12 (or .pfx) file.

The Content-Type and Content-Disposition email headers of the email to be decrypted look similar to this:

Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data;
	name="smime.p7m"
Content-Disposition: attachment; filename="smime.p7m"

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;
email: TChilkatEmail;

begin
success := 0;

email := TChilkatEmail.Create(Self);

// Add a PFX (or .p12) to be used for decryption
success := email.AddPfxSourceFile('myCert.p12','passwordForP12');
if (success <> 1) then
  begin
    Memo1.Lines.Add(email.LastErrorText);
    Exit;
  end;

// Loading the .eml automatically decrypts.
success := email.LoadEml('encrypted.eml');
if (success <> 1) then
  begin
    Memo1.Lines.Add(email.LastErrorText);
    Exit;
  end;

// The email now exists as it was prior to encryption.
// Your app may access the email's subject, body, attachments,
// etc. using the Chilkat Email API...

// Save the decrypted email:
success := email.SaveEml('decrypted.eml');
if (success <> 1) then
  begin
    Memo1.Lines.Add(email.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Success.');
end;