Dart

Export an Encrypted PKCS #8 Private Key as PEM

Demonstrates the Chilkat PrivateKey.GetPkcs8EncryptedPem method, which exports the key as password-protected PKCS #8 PEM (-----BEGIN ENCRYPTED PRIVATE KEY-----). The only argument is the password; the cipher is selected by the Pkcs8EncryptAlg property.

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 safe way to export a key for storage or transfer — the private material is encrypted under a passphrase, so a leaked file is not immediately usable. It is the format to reach for whenever a key leaves your process. Control the encryption cipher with Pkcs8EncryptAlg, and source the password securely rather than hard-coding it.

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Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // Load a private key to export.
  final privKey = CkPrivateKey();
  try {
    privKey.loadPemFile('qa_data/private.pem');
  } on ChilkatException catch (e) {
    print(e.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.
  final password = 'myKeyPassword';

  // Export as password-protected PKCS #8 PEM ("-----BEGIN ENCRYPTED PRIVATE KEY-----").  The
  // encryption cipher is selected by the Pkcs8EncryptAlg property.
  final String pem;
  try {
    pem = privKey.getPkcs8EncryptedPem(password);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print(pem);
}