public static void initPrivateKey(Properties props) throws Exception {

    String privateKeyFilePath = props.getProperty(PRIVATE_KEY_FILE_PROP);
    privateKeyAlias = "";
    privateKeyEncrypt = null;
    if (privateKeyFilePath != null && privateKeyFilePath.length() > 0) {
      KeyStore ks = KeyStore.getInstance("PKCS12");
      privateKeyAlias = props.getProperty(PRIVATE_KEY_ALIAS_PROP);
      if (privateKeyAlias == null) {
        privateKeyAlias = "";
      }
      String keyStorePass = props.getProperty(PRIVATE_KEY_PASSWD_PROP);
      char[] passPhrase = (keyStorePass != null ? keyStorePass.toCharArray() : null);
      FileInputStream privateKeyFile = new FileInputStream(privateKeyFilePath);
      try {
        ks.load(privateKeyFile, passPhrase);
      } finally {
        privateKeyFile.close();
      }
      Key key = ks.getKey(privateKeyAlias, passPhrase);
      Certificate keyCert = ks.getCertificate(privateKeyAlias);
      if (key instanceof PrivateKey && keyCert instanceof X509Certificate) {
        privateKeyEncrypt = (PrivateKey) key;
        privateKeySignAlgo = ((X509Certificate) keyCert).getSigAlgName();
        privateKeySubject = ((X509Certificate) keyCert).getSubjectDN().getName();
      }
    }
  }
Load the private key of the server. This method is not thread safe.
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/EncryptorImpl.java