Android™

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.

Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    boolean 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.)
    CkCert cert = new CkCert();
    success = cert.LoadFromFile("qa_data/rsaes-oaep/cert.pem");
    if (success != true) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    CkEmail email = new CkEmail();

    //  Create a simple email.
    email.put_Subject("Sample RSAES-OAEP Encrypted Email");
    email.put_Body("Sample RSAES-OAEP Encrypted Email");
    email.put_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.put_Pkcs7CryptAlg("aes");
    //  If AES-256 is desired, set the following property to 256.
    email.put_Pkcs7KeyLength(128);
    email.put_OaepPadding(true);
    //  Other choices for the OAEP hash algorithm are "sha1", "sha384", and "sha512"
    email.put_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.put_SendEncrypted(true);

    //  The mailman object will do the RSAES-OAEP encryption when sending.
    CkMailMan mailman = new CkMailMan();

    //  Set the SMTP settings for your email account on your mail server.
    mailman.put_SmtpUsername("SMTP_LOGIN");
    mailman.put_SmtpPassword("SMTP_PASSWORD");
    mailman.put_SmtpHost("MY_SMTP_DOMAIN_OR_IP");
    mailman.put_SmtpPort(587);
    mailman.put_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) {
        Log.i(TAG, mailman.lastErrorText());
        return;
        }

    success = mailman.CloseSmtpConnection();
    if (success != true) {
        Log.i(TAG, "Connection to SMTP server not closed cleanly.");
        }

    Log.i(TAG, "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=

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}