code: function decrypt(message) {
    if (this.secure && this.cipher && this.secret) {
      if (this.secret === 'secret') {
        console.warn('PLEASE change default secret password!');
      }
      debug('%s decrypt message with %s', this.name, this.cipher);
      var decipher = crypto.createDecipher(this.cipher, this.secret);
      return Buffer.concat([decipher.update(message), decipher.final()]);
    }
    return message;
  }
docs: Decrypt a message
  @param {Buffer} message The encrypted message
  @return {Buffer} The decrypted buffer
  @ignore