(Android™) Export a Certificate's Private Key to Various Formats

Loads a digital certificate and private key from a PFX file (also known as PKCS#12) and exports the private key to various formats: (1) PKCS8 Encrypted, (2) PKCS8 Encrypted PEM, (3) PKCS8 unencrypted, (4) PKCS8 PEM unencrypted, (5) RSA DER unencrypted, (6) RSA PEM unencrypted, (7) XML.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// 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);

    CkCert cert = new CkCert();

    // Load from the PFX file
    String pfxFilename = "/Users/chilkat/testData/pfx/chilkat_ssl_pwd_is_test.pfx";
    String pfxPassword = "test";

    // A PFX typically contains certificates in the chain of authentication.
    // The Chilkat cert object will choose the certificate w/
    // private key farthest from the root authority cert.
    // To access all the certificates in a PFX, use the 
    // Chilkat certificate store object instead.
    boolean success = cert.LoadPfxFile(pfxFilename,pfxPassword);
    if (success != true) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    // Get the private key...
    CkPrivateKey privKey;
    privKey = cert.ExportPrivateKey();
    if (cert.get_LastMethodSuccess() == false) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    // Export to various formats:

    String password = "secret";
    String path;

    // PKCS8 Encrypted DER
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.der";
    success = privKey.SavePkcs8EncryptedFile(password,path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    // PKCS8 Encrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.pem";
    success = privKey.SavePkcs8EncryptedPemFile(password,path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    // PKCS8 Unencrypted DER
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.der";
    success = privKey.SavePkcs8File(path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    // PKCS8 Unencrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.pem";
    success = privKey.SavePkcs8PemFile(path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    //  RSA DER (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.der";
    success = privKey.SavePkcs1File(path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    // RSA PEM (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.pem";
    success = privKey.SavePemFile(path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    // XML (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat.xml";
    success = privKey.SaveXmlFile(path);
    if (success != true) {
        Log.i(TAG, privKey.lastErrorText());

        return;
        }

    Log.i(TAG, "Private key exported to all formats.");

  }

  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."
  }
}