Pascal (Lazarus/Delphi)

Send Encrypted Email using RSAES-OAEP with AES-128 CBC and SHA256

See more SMTP Examples

Demonstrates how to send encrypted email using RSAES-OAEP with SHA256 and AES-128 content encryption.

Note: This example requires Chilkat v9.5.0.67 or greater.

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;
  cert: TCert;
  email: TEmail;
  mailman: TMailMan;

begin
  success := False;

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

  //  Load an RSA-based certificate.
  //  (Encrypting an email only requires the public key.  Decrypting an email requires the private key.)
  cert := TCert.Create;
  success := cert.LoadFromFile('qa_data/rsaes-oaep/cert.pem');
  if (success <> True) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  email := TEmail.Create;

  //  Create a simple email.
  email.Subject := 'Sample RSAES-OAEP Encrypted Email';
  email.Body := 'Sample RSAES-OAEP Encrypted Email';
  email.From := 'support@chilkatsoft.com';

  //  Add a recipient.
  //  (The email is encrypted using the recipient's certificate.
  //  If sending to multiple recipients, then the AddEncryptCert method would
  //  need to be called once for each recipient's certificate.)
  email.AddTo('Chilkat GMail','chilkat.support@gmail.com');

  //  Set the email object properties to indicate the desired encryption.
  email.Pkcs7CryptAlg := 'aes';
  //  If AES-256 is desired, set the following property to 256.
  email.Pkcs7KeyLength := 128;
  email.OaepPadding := True;
  //  Other choices for the OAEP hash algorithm are "sha1", "sha384", and "sha512"
  email.OaepHash := 'sha256';

  //  Provide the certificate to be used for encryption
  email.AddEncryptCert(cert);

  //  Don't forget to indicate that the email should be encrypted when sent..
  email.SendEncrypted := True;

  //  The mailman object will do the RSAES-OAEP encryption when sending.
  mailman := TMailMan.Create;

  //  Set the SMTP settings for your email account on your mail server.
  mailman.SmtpUsername := 'SMTP_LOGIN';
  mailman.SmtpPassword := 'SMTP_PASSWORD';
  mailman.SmtpHost := 'MY_SMTP_DOMAIN_OR_IP';
  mailman.SmtpPort := 587;
  mailman.StartTLS := True;

  //  Send the email.  The mailman will encrypt the email as directed by the 
  //  property settings of the email object.
  success := mailman.SendEmail(email);
  if (success <> True) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  success := mailman.CloseSmtpConnection();
  if (success <> True) then
    begin
      WriteLn('Connection to SMTP server not closed cleanly.');
    end;

  WriteLn('Mail Sent!');

  //  -----------------------------------------------------------
  //  This is an example of an RSAES-OAEP encrypted email
  //  -----------------------------------------------------------

  //  MIME-Version: 1.0
  //  Date: Thu, 27 Apr 2017 08:43:32 -0500
  //  Message-ID: <772DC039F0259C474BAC60240EA2BA2272402308@CHILKAT13>
  //  Content-Type: application/pkcs7-mime; name="smime.p7m"; smime-type="enveloped-data"
  //  Content-Transfer-Encoding: base64
  //  X-Priority: 3 (Normal)
  //  Subject: Sample RSAES-OAEP Encrypted Email
  //  From: support@chilkatsoft.com
  //  To: "Chilkat GMail" <chilkat.support@gmail.com>
  //  Content-Disposition: attachment; filename="smime.p7m"
  //  
  //  MIICWQYJKoZIhvcNAQcDoIICSjCCAkYCAQAxggGgMIIBnAIBADB1MGgxCzAJBgNVBAYTAlVTMQsw
  //  CQYDVQQIDAJJTDEQMA4GA1UEBwwHV2hlYXRvbjEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQ
  //  dHkgTHRkMRcwFQYDVQQDDA5DaGlsa2F0V2lkZ2V0cwIJAMRwugDmvniwMBwGCSqGSIb3DQEBBzAP
  //  oA0wCwYJYIZIAWUDBAIBBIIBABr0E1dKJjK0FAYRz/NCtJmBeB0nUxgcuBnhGPI/UeyGub3cCo+K
  //  G5F4/iVTBJqVvYIF5+fvBnyTginwv7OiUiFWLyihiFC3NIyZJO22+XMHpNatCffTPZk10WswkTgk
  //  G3ApnRvGQAaldnFD0Hs8drPU4vBvY9QsjT7YDGa6u2NMX+sr1ewEZArqU0mNfJ6RsEYd5FQbFEVF
  //  qLmnz8Dt+yhoJlUtfUd8TXIeqHRJ7RxKOTSzlBZaAdTv2QX4oL9IcAgZeTg5iw+yRPkSAwWyg+I/
  //  7fybLsUpRGDHTGUU+AvHvP0kYKa1mkvccBVEC/+4hEyhpS1tWIR5ByY6vM76Z+8wgZwGCSqGSIb3
  //  DQEHATAdBglghkgBZQMEAQIEEKqD0YDHX1NsVDaV32UczpeAcLteQyRPTV4hATjwcPiVelPfeWNs
  //  xZKRGaEBqLM8+Y+V4ciCFoOlgJuOcP4m1PTHyilfzd+SCsKz5l1C7+sfPf36n2aacX6IWga59Bz5
  //  QbWrOHDUT7O5PnGwKVgQFw3Cj4GrdPGWKcoqxB0HuKnj3WA=


  cert.Free;
  email.Free;
  mailman.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.