if ( !DEFAULT_CHECKSUMS.containsKey( checksum.getChecksumType() ) )
{
throw new KerberosException( ErrorType.KDC_ERR_SUMTYPE_NOSUPP );
}
ChecksumType checksumType = checksum.getChecksumType();
ChecksumEngine digester = getEngine( checksumType );
Checksum newChecksum = new Checksum( checksumType, digester.calculateChecksum( bytes, key, usage ) );
if ( !newChecksum.equals( checksum ) )
{