/// <summary>
/// Filters all received packets from PacketList
/// </summary>
private void FilterAllPackets()
{
// To filter all packets, we must refresh the whole list
FilteredPacketList.Clear();
lock (PacketList)
{
foreach (IPPacket packet in PacketList)
{
lock (FilteredPacketList)
{
AddToFilteredList(packet);
}
}
}
// This condition here avoids threading problem:
// If a new packet is captured just before FilterAllPackets() is called,
// this removes all newPackets that arrived before this function call.
while (FilteredPacketList.Count > 2)
{
uint firstPacketID = filteredPacketList[0].PacketID;
uint lastPacketID = filteredPacketList[filteredPacketList.Count - 2].PacketID;
if (firstPacketID > lastPacketID)
{
filteredPacketList.RemoveAt(0);
continue;
}
break;
}
}
private void ClearPacketListExecute()
{
PacketList.Clear();
FilteredPacketList.Clear();
StatsHandler.ResetStats();
if (monitor != null)
{
StatsHandler.StopWatch.Start();
}
ClearSelectedPacketData();
IsClearEnabled = false;
}
/// <summary>
/// Decides whether newPacket should be added to FilteredPacketList or not
/// </summary>
/// <param name="newPacket">Packet to be processed and added to FilteredPacketList if it satisfies filter conditions</param>
private void AddToFilteredList(IPPacket newPacket)
{
// If the filterString is empty, just add newPacket to the FilterPacketList
if (string.IsNullOrEmpty(filter))
{
FilteredPacketList.Add(newPacket);
return;
}
// If none of the substrings uses the proper syntax, ignore it and add packet
// as if there was no filter at all.
if (protocolList.Count == 0 && protocolListToExclude.Count == 0 && srcIPList.Count == 0 &&
destIPList.Count == 0 && srcPortList.Count == 0 && destPortList.Count == 0 &&
higherLengthList.Count == 0 && lowerLengthList.Count == 0)
{
FilteredPacketList.Add(newPacket);
return;
}
// These are rules a newPacket must satisfy to be added in the FilteredPacketList.
// By default all rules are true, so in case one of the condition list is empty
// a newPacket could be added to FilteredList. Otherwise it is set to false once it
// enters foreach loop where it must satisfy the conditon to be set to true
bool IncludeProtocolRule = true;
bool ExcludeProtocolRule = false;
bool SrcIPRule = true;
bool DstIPRule = true;
bool SrcPortRule = true;
bool DestPortRule = true;
bool LowerLengthRule = true;
bool HigherLengthRule = true;
// Checking empty protocolList would change the default value of IncludeProtocolRule to false
if (protocolList.Count != 0)
{
IncludeProtocolRule = ApplyProtocolRule(newPacket, protocolList);
}
if (protocolListToExclude.Count != 0)
{
ExcludeProtocolRule = ApplyProtocolRule(newPacket, protocolListToExclude);
}
foreach (string ip in srcIPList)
{
SrcIPRule = false;
if (ip == newPacket.IPHeader[0].SourceIPAddress.ToString())
{
SrcIPRule = true;
break;
}
}
foreach (string ip in destIPList)
{
DstIPRule = false;
if (ip == newPacket.IPHeader[0].DestinationIPAddress.ToString())
{
DstIPRule = true;
break;
}
}
foreach (string port in srcPortList)
{
SrcPortRule = false;
if (newPacket.TCPPacket.Count > 0 &&
port == newPacket.TCPPacket[0].TCPHeader[0].SourcePort.ToString())
{
SrcPortRule = true;
break;
}
else if (newPacket.UDPPacket.Count > 0 &&
port == newPacket.UDPPacket[0].UDPHeader[0].SourcePort.ToString())
{
SrcPortRule = true;
break;
}
}
foreach (string port in destPortList)
{
DestPortRule = false;
if (newPacket.TCPPacket.Count > 0 &&
port == newPacket.TCPPacket[0].TCPHeader[0].DestinationPort.ToString())
{
DestPortRule = true;
break;
}
else if (newPacket.UDPPacket.Count > 0 &&
port == newPacket.UDPPacket[0].UDPHeader[0].DestinationPort.ToString())
{
DestPortRule = true;
break;
}
}
ushort packetLength = newPacket.IPHeader[0].TotalLength;
foreach (string LowerLength in lowerLengthList)
{
LowerLengthRule = false;
ushort lowerLenght = ushort.Parse(LowerLength);
if (lowerLenght > packetLength)
{
LowerLengthRule = true;
break;
}
}
foreach (string HigherLength in higherLengthList)
{
HigherLengthRule = false;
ushort higherLenght = ushort.Parse(HigherLength);
if (higherLenght < packetLength)
{
HigherLengthRule = true;
break;
}
}
// If newPacket satisfies all the filter rules, add it to filteredPacketList
if (IncludeProtocolRule == true && ExcludeProtocolRule == false && SrcIPRule == true &&
DstIPRule == true && SrcPortRule == true && DestPortRule == true &&
LowerLengthRule == true && HigherLengthRule == true)
{
FilteredPacketList.Add(newPacket);
}
}
