Java

Save a Private Key as an Encrypted PKCS #8 DER File

Demonstrates the Chilkat PrivateKey.SavePkcs8EncryptedFile method, which saves the key as password-protected PKCS #8 DER. The first argument is the password and the second is the destination path. The cipher is selected by Pkcs8EncryptAlg.

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: This is the recommended way to persist a key to disk: the binary .der is encrypted under a passphrase, so a stolen file is useless without it. Reach for it whenever a key is stored or shipped. Choose the encryption cipher with Pkcs8EncryptAlg and source the password securely.

Chilkat Java Downloads

Download Chilkat for Java

Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.PrivateKey;

public class ChilkatExample {

    public static void main(String[] args) {
        // Load a private key to export.
        PrivateKey privKey = new PrivateKey();
        try {
            privKey.loadPemFile("qa_data/private.pem");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // The key password is not hard-coded in a real application; obtain it from an interactive
        // prompt, environment variable, or a secrets vault.
        String password = "myKeyPassword";

        // Save as password-protected PKCS #8 DER.  The 1st argument is the password and the 2nd is the
        // destination path.  The cipher is selected by the Pkcs8EncryptAlg property.
        try {
            privKey.savePkcs8EncryptedFile(password, "qa_output/private_pkcs8_enc.der");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Saved (encrypted).");
    }
}