public bool CheckIfMatched(ref SecurityEvent securityEvent, ref Rule rule)
{
string padding = Assistant.GetPadding();
// Check <if_sid> element => scan dependencies and matchList
if (rule.ifSID != 0)
{
logger.Trace("{0}Check <if_sid>{1}</if_sid>", padding, rule.ifSID);
if (!matchList.ContainsKey(rule.ifSID))
{
return(false);
}
if (matchList[rule.ifSID] == 0)
{
return(false);
}
}
// Check <same_source_ip> element
if (!rule.sourceIP.Equals(""))
{
logger.Trace(padding + " Check <same_source_ip/>");
if (!securityEvent.srcIP.Equals(rule.sourceIP))
{
return(false);
}
}
// Check <match> element
if (!rule.match.Equals(""))
{
logger.Trace("{0}Check <match>{1}</match>", padding, rule.match);
// Process logical OR
bool check = false;
string[] parts = rule.match.Split(new Char[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
foreach (string part in parts)
{
if (securityEvent.message.IndexOf(part, StringComparison.OrdinalIgnoreCase) >= 0)
{
check = true;
break;
}
}
if (!check)
{
return(false);
}
}
// Check <if_matched_sid> element
if (rule.ifMatchedSID != 0)
{
logger.Trace("{0}Check <if_matched_sid>{1}</if_matched_sid>", padding, rule.ifMatchedSID);
if (matchList.ContainsKey(rule.ifMatchedSID))
{
if (matchList[rule.ifMatchedSID] == 0)
{
return(false);
}
// Scan FireQueue
if (!fireDictionary.ContainsKey(rule.ifMatchedSID))
{
return(false);
}
if (fireDictionary[rule.ifMatchedSID].CheckIfMatched(securityEvent, rule))
{
logger.Trace("{0} Rule {1} QueueDictionary.CheckIfMatched == TRUE", padding, rule.ifMatchedSID);
}
else
{
logger.Trace("{0} Rule {1} QueueDictionary.CheckIfMatched == FALSE", padding, rule.ifMatchedSID);
return(false);
}
}
}
// Rule matched
return(true);
}