Android™

Set the DKIM Signing Private Key

Demonstrates the Chilkat Dkim.SetDkimPrivateKey method, which supplies the RSA private key used by DkimSign. The only argument is a PrivateKey object. The source key may be destroyed after this returns, and the configured key can be reused for multiple signatures.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: DKIM proves a message really came from its domain by signing it with a private key that only the domain owner holds; recipients verify with the matching public key published in the domain's DNS. This method loads that private half into the Dkim object once, so a mail server can sign every outgoing message without re-reading the key each time. Because the key is the domain's signing secret, it should be protected like any other private key and never committed to source.

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// 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;

    //  Demonstrates the Dkim.SetDkimPrivateKey method, which supplies the RSA private key used by
    //  DkimSign.  The only argument is a PrivateKey object.

    CkDkim dkim = new CkDkim();

    //  Load the RSA private key that corresponds to the public key published in the domain's DNS.
    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadPemFile("qa_data/dkim_private.pem");
    if (success == false) {
        Log.i(TAG, privKey.lastErrorText());
        return;
        }

    //  Copy the key into the Dkim object.  The PrivateKey object may be destroyed afterward, and the
    //  configured key can be reused for multiple signatures.
    success = dkim.SetDkimPrivateKey(privKey);
    if (success == false) {
        Log.i(TAG, dkim.lastErrorText());
        return;
        }

    Log.i(TAG, "DKIM private key configured.");

  }

  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."
  }
}