Android™

Send aes-gcm authEnvelopedData Encrypted Email

See more SMTP Examples

Note: This example requires Chilkat v10.0.0 or later

Demonstrates how to send encrypted email using 128-bit AES in GCM mode.

"AES-GCM" (Advanced Encryption Standard - Galois/Counter Mode) is a cryptographic algorithm that provides both encryption and integrity protection (authentication). When used in the context of email security with "authEnvelopedData", it often refers to a method of securely sending encrypted and authenticated email content.

Here’s a brief breakdown:

• AES-GCM: Combines symmetric encryption (AES) with authentication, ensuring both the confidentiality and integrity of the message. It generates an authentication tag to detect any unauthorized changes.
• authEnvelopedData: Refers to a type of structure used in secure email protocols (like S/MIME) to package encrypted content. It contains the encrypted data and associated encrypted session keys.
• Email Security: When applied to emails, AES-GCM ensures the email content is encrypted (confidential) and also tamper-resistant (authenticated), with the encryption keys typically shared securely using asymmetric encryption (e.g., public key infrastructure, or PKI).

In short, AES-GCM with "authEnvelopedData" provides a way to encrypt and authenticate emails, making them confidential and resistant to tampering.

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.

    // The mailman object is used for sending and receiving email.
    CkMailMan mailman = new CkMailMan();

    mailman.put_SmtpHost("smtp.example.com");

    mailman.put_SmtpUsername("my_smtp_login");
    mailman.put_SmtpPassword("my_smtp_password");

    // The typical SMTP ports are 465 for implicit SSL/TLS or 587 for explicit SSL/TLS
    mailman.put_SmtpPort(465);
    mailman.put_SmtpSsl(true);

    // Use the recipient's certificate for encryption.
    CkCert cert = new CkCert();
    success = cert.LoadFromFile("c:/someDir/recipient_cert.cer");
    if (success != true) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    CkEmail email = new CkEmail();

    email.put_Subject("This email is encrypted");
    email.put_Body("This is AES-GCM encrypted mail");
    email.put_From("Mary <mary@example1.com>");
    success = email.AddTo("Joe","joe@example.com");

    // Specify that AES-GCM w/ authEnvelopedData is to be used. 
    // Also specify other params..
    email.put_Pkcs7CryptAlg("aes-gcm");
    email.put_Pkcs7KeyLength(128);
    email.put_OaepPadding(true);
    email.put_OaepHash("sha256");
    email.put_OaepMgfHash("sha256");

    // Indicate the email is to be sent encrypted.
    email.put_SendEncrypted(true);

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

    success = mailman.SendEmail(email);
    if (success != true) {
        Log.i(TAG, mailman.lastErrorText());
        }
    else {
        Log.i(TAG, "Mail Sent!");
        }


  }

  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."
  }
}