/** {@inheritDoc} */
 @Override
 public StatusCode validateCertificate(Cert c) {
   for (Cert certs : trustedCertificates) if (certs.equals(c)) return null;
   for (PublicKey key : trustedPublicKeys) {
     try {
       c.getCertificate().verify(key);
       return null;
     } catch (GeneralSecurityException e) {
       continue;
     }
   }
   return new StatusCode(StatusCodes.Bad_SecurityChecksFailed);
 }