/**
  * @see AbstractPublicKey::verify($message, $signature)
  */
 public function verify($message, $signature)
 {
     return $this->rsa->verify($message, $signature);
 }
 /**
  * @see AbstractSecretKey::sign($message)
  */
 public function sign($message)
 {
     return $this->rsa->sign($message);
 }