protected static int CalculateRecordMac(KeyParameter macKey, byte[] additionalData, byte[] buf, int off, int len, byte[] outMac)
{
_mac.Reset();
_mac.Init(macKey);
UpdateRecordMacText(_mac, additionalData, 0, additionalData.Length);
UpdateRecordMacText(_mac, buf, off, len);
UpdateRecordMacLength(_mac, additionalData.Length);
UpdateRecordMacLength(_mac, len);
return(MacUtilities.DoFinalOut(_mac, outMac));
}