Pascal (Lazarus/Delphi)

Send Encrypted Email with a Selected Algorithm (AES, 3DES, etc.)

Sends an encrypted email using the recipient's digital certificate from a .cer file, and chooses 3DES for the encryption algorithm. (It is also possible to send AES encrypted email w/ 128-bit, 192-bit, or 256-bit encryption simply by setting the Pkcs7CryptAlg and Pkcs7KeyLength properties.) Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.MailMan,
  Chilkat.Cert,
  Chilkat.Email;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  mailman: TMailMan;
  cert: TCert;
  email: TEmail;

begin
  success := False;

  //  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 := TMailMan.Create;

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

  //  Load the .cer file into a certificate object.
  //  When sending S/MIME encrypted email, it is the recipient's
  //  certificate that is used for encryption.  Only the public key
  //  is needed to encrypt.  The recipient is the only
  //  one possessing the private key, and therefore is the only
  //  one able to decrypt.
  cert := TCert.Create;
  success := cert.LoadFromFile('cknotes.cer');
  if (success <> True) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  //  Create a new email object
  email := TEmail.Create;

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

  //  Indicate that the email is to be sent encrypted.
  email.SendEncrypted := True;

  //  Specify the certificate to be used for encryption.
  success := email.SetEncryptCert(cert);

  //  If desired, specify the encryption algorithm to be used.
  //  The Pkcs7CryptAlg property can be set to "aes", "des", "3des", or "rc2"
  email.Pkcs7CryptAlg := '3des';

  //  If desired, set the key length (in bits) for the encryption algorithm:
  //  The possible values allowed depend on the Pkcs7CryptAlg property. 
  //  For "aes", the key length may be 128, 192, or 256. 
  //  For "3des" the key length must be 192. 
  //  For "des" the key length must be 40. 
  //  For "rc2" the key length can be 40, 56, 64, or 128.
  email.Pkcs7KeyLength := 192;

  success := mailman.SendEmail(email);
  if (success <> True) then
    begin
      WriteLn(mailman.LastErrorText);
    end
  else
    begin
      WriteLn('Mail Sent!');
    end;


  mailman.Free;
  cert.Free;
  email.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.