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Node.js

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

See more Private Key Examples

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 Node.js Downloads

Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

    //  Load a private key to export.
    var privKey = new chilkat.PrivateKey();
    success = privKey.LoadPemFile("qa_data/private.pem");
    if (success == false) {
        console.log(privKey.LastErrorText);
        return;
    }

    //  The key password is not hard-coded in a real application; obtain it from an interactive
    //  prompt, environment variable, or a secrets vault.
    var 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.
    success = privKey.SavePkcs8EncryptedFile(password,"qa_output/private_pkcs8_enc.der");
    if (success == false) {
        console.log(privKey.LastErrorText);
        return;
    }

    console.log("Saved (encrypted).");

}

chilkatExample();