// main routine
public override PacketMainReturn interiorMain(ref Packet in_packet)
{
// if the packet is ICMPv4
if (in_packet.GetHighestLayer() == Protocol.ICMP)
{
ICMPPacket packet = (ICMPPacket)in_packet;
// check if the packet is allowed and deny all is false
if (isAllowed(packet.Type.ToString(), packet.Code.ToString(), 4) &&
!data.DenyIPv4)
{
return null;
}
// else, log and drop it
else
{
PacketMainReturn pmr;
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop;
if (data.Log)
{
pmr.returnType |= PacketMainReturnType.Log;
pmr.logMessage = "ICMP from " + packet.SourceIP.ToString() + " for " +
packet.DestIP.ToString() + " was dropped.";
}
return pmr;
}
}
// if the packet is ICMPv6
if (in_packet.GetHighestLayer() == Protocol.ICMPv6)
{
ICMPv6Packet packet = (ICMPv6Packet)in_packet;
if ((isAllowed(packet.Type.ToString(), packet.Code.ToString(), 6) &&
!data.DenyIPv6) && isDeniedNDP(packet))
{
return null;
}
else
{
PacketMainReturn pmr;
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop;
if (data.Log)
{
pmr.returnType |= PacketMainReturnType.Log;
pmr.logMessage = "ICMPv6 from " + packet.SourceIP.ToString() + " for " +
packet.DestIP.ToString() + " was dropped.";
}
return pmr;
}
}
return null;
}
public override PacketMainReturn interiorMain(ref Packet in_packet)
{
// let the packet through
PacketMainReturn pmr = new PacketMainReturn(MODULE_NAME);
pmr.returnType = PacketMainReturnType.Allow;
try
{
// get a usable form of the packet
Protocol highestLayer = in_packet.GetHighestLayer();
string type = "";
bool outbound = false;
uint length = 0;
string ip = "";
switch (highestLayer)
{
case Protocol.TCP:
TCPPacket tcpPacket = (TCPPacket)in_packet;
type = TCP;
outbound = tcpPacket.Outbound;
length = tcpPacket.Length();
ip = outbound ? tcpPacket.DestIP.ToString() : tcpPacket.SourceIP.ToString();
break;
case Protocol.UDP:
UDPPacket udpPacket = (UDPPacket)in_packet;
type = UDP;
length = udpPacket.Length();
ip = outbound ? udpPacket.DestIP.ToString() : udpPacket.SourceIP.ToString();
break;
case Protocol.ARP:
ARPPacket arpPacket = (ARPPacket)in_packet;
type = ARP;
outbound = arpPacket.Outbound;
length = arpPacket.Length();
ip = outbound ? arpPacket.ATargetIP.ToString() : arpPacket.ASenderIP.ToString();
break;
case Protocol.DHCP:
// no packet structure for this type
break;
case Protocol.DNS:
DNSPacket dnsPacket = (DNSPacket)in_packet;
type = DNS;
outbound = dnsPacket.Outbound;
length = dnsPacket.Length();
ip = outbound ? dnsPacket.DestIP.ToString() : dnsPacket.SourceIP.ToString();
break;
case Protocol.EEth:
EETHPacket eethPacket = (EETHPacket)in_packet;
type = EETH;
outbound = eethPacket.Outbound;
length = eethPacket.Length();
ip = NO_IP;
break;
case Protocol.Ethernet:
EthPacket ethPacket = (EthPacket)in_packet;
type = ETHERNET;
outbound = ethPacket.Outbound;
length = ethPacket.Length();
ip = NO_IP;
break;
case Protocol.ICMP:
ICMPPacket icmpPacket = (ICMPPacket)in_packet;
type = ICMP;
outbound = icmpPacket.Outbound;
length = icmpPacket.Length();
ip = ip = outbound ? icmpPacket.DestIP.ToString() : icmpPacket.SourceIP.ToString();
break;
case Protocol.ICMPv6:
ICMPv6Packet icmpv6Packet = (ICMPv6Packet)in_packet;
type = ICMPV6;
outbound = icmpv6Packet.Outbound;
length = icmpv6Packet.Length();
ip = outbound ? icmpv6Packet.DestIP.ToString() : icmpv6Packet.SourceIP.ToString();
break;
case Protocol.IP:
IPPacket ipPacket = (IPPacket)in_packet;
type = IP;
outbound = ipPacket.Outbound;
length = ipPacket.Length();
ip = outbound ? ipPacket.DestIP.ToString() : ipPacket.SourceIP.ToString();
break;
case Protocol.SNMP:
// no packet structure available for this type
break;
default:
break;
}
if (type != "")
{
bufferStatement("insert into connection_log values (" + (outbound ? DIRECTION_OUTBOUND : DIRECTION_INBOUND) + "," +
DateTime.Now.Ticks + ",'" + ip + "'," + length + ",'" + type + "')"); // using Length here...
// should TotalLength be used instead?
}
}
catch (Exception e)
{
PassThru.LogCenter.Instance.Push(MODULE_NAME, e.Message);
}
return pmr;
}
public override PacketMainReturn interiorMain(ref Packet in_packet)
{
if (in_packet.GetHighestLayer() == Protocol.ARP)
{
ARPPacket arpp = (ARPPacket)in_packet;
if (arpp.isRequest && arpp.Outbound)
{
int ip = arpp.ATargetIP.GetHashCode();
if (!requestedIPs.Contains(ip))
requestedIPs.Add(ip);
}
else if (!arpp.Outbound)
{
int ip = arpp.ASenderIP.GetHashCode();
if (!arpp.isRequest)
{
if (requestedIPs.Contains(ip))
{
lock (padlock)
{
if (data.arpCache.ContainsKey(arpp.ASenderIP))
{
if (!Compare(data.arpCache[arpp.ASenderIP], arpp.ASenderMac))
{
PacketMainReturn pmr = new PacketMainReturn(this);
if (data.RectifyAttacks)
pmr.returnType = PacketMainReturnType.Edited;
else
pmr.returnType = PacketMainReturnType.Drop;
if (data.LogAttacks)
pmr.returnType |= PacketMainReturnType.Log | PacketMainReturnType.Popup;
switch (LanguageConfig.GetCurrentLanguage())
{
case LanguageConfig.Language.NONE:
case LanguageConfig.Language.ENGLISH:
pmr.logMessage = "ARP Response from " + new PhysicalAddress(arpp.ASenderMac).ToString() + " for " + arpp.ASenderIP.ToString() + " does not match the ARP cache.";
break;
case LanguageConfig.Language.CHINESE:
pmr.logMessage = new PhysicalAddress(arpp.ASenderMac).ToString() + "为" + arpp.ASenderIP.ToString() + "的ARP响应不匹配的ARP缓存。";
break;
case LanguageConfig.Language.GERMAN:
pmr.logMessage = "ARP Response von " + new PhysicalAddress(arpp.ASenderMac).ToString() + " für " + arpp.ASenderIP.ToString() + " nicht mit dem ARP-Cache.";
break;
case LanguageConfig.Language.RUSSIAN:
pmr.logMessage = "ARP-ответ от " + new PhysicalAddress(arpp.ASenderMac).ToString() + " для " + arpp.ASenderIP.ToString() + " не соответствует кэш ARP.";
break;
case LanguageConfig.Language.SPANISH:
pmr.logMessage = "Respuesta de ARP de " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " no coincide con la caché ARP.";
break;
case LanguageConfig.Language.PORTUGUESE:
pmr.logMessage = "Resposta da ARP " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " não coincide com o cache ARP.";
break;
}
if (data.RectifyAttacks)
{
arpp.ATargetIP = arpp.ASenderIP;
arpp.ATargetMac = data.arpCache[arpp.ATargetIP];
arpp.ASenderMac = adapter.InterfaceInformation.GetPhysicalAddress().GetAddressBytes();
arpp.FromMac = arpp.ASenderMac;
arpp.ToMac = arpp.ATargetMac;
foreach (UnicastIPAddressInformation ipv4 in adapter.InterfaceInformation.GetIPProperties().UnicastAddresses)
{
if (ipv4.Address.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
{
arpp.ASenderIP = ipv4.Address;
break;
}
}
arpp.Outbound = true;
in_packet = arpp;
}
return pmr;
}
else
{
requestedIPs.Remove(ip);
}
}
else
{
data.arpCache[arpp.ASenderIP] = arpp.ASenderMac;
if (UpdatedArpCache != null)
UpdatedArpCache();
requestedIPs.Remove(ip);
}
}
}
else
{
lock (padlock)
{
if (data.arpCache.ContainsKey(arpp.ASenderIP))
{
if (!Compare(data.arpCache[arpp.ASenderIP], arpp.ASenderMac))
{
PacketMainReturn pmra = new PacketMainReturn(this);
if (data.RectifyAttacks)
pmra.returnType = PacketMainReturnType.Edited;
else
pmra.returnType = PacketMainReturnType.Drop | PacketMainReturnType.Popup;
switch (LanguageConfig.GetCurrentLanguage())
{
case LanguageConfig.Language.NONE:
case LanguageConfig.Language.ENGLISH:
pmra.logMessage = "ARP Response from " + new PhysicalAddress(arpp.ASenderMac).ToString() + " for " + arpp.ASenderIP.ToString() + " does not match the ARP cache.";
break;
case LanguageConfig.Language.CHINESE:
pmra.logMessage = new PhysicalAddress(arpp.ASenderMac).ToString() + "为" + arpp.ASenderIP.ToString() + "的ARP响应不匹配的ARP缓存。";
break;
case LanguageConfig.Language.GERMAN:
pmra.logMessage = "ARP Response von " + new PhysicalAddress(arpp.ASenderMac).ToString() + " für " + arpp.ASenderIP.ToString() + " nicht mit dem ARP-Cache.";
break;
case LanguageConfig.Language.RUSSIAN:
pmra.logMessage = "ARP-ответ от " + new PhysicalAddress(arpp.ASenderMac).ToString() + " для " + arpp.ASenderIP.ToString() + " не соответствует кэш ARP.";
break;
case LanguageConfig.Language.SPANISH:
pmra.logMessage = "Respuesta de ARP de " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " no coincide con la caché ARP.";
break;
case LanguageConfig.Language.PORTUGUESE:
pmra.logMessage = "Resposta da ARP " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " não coincide com o cache ARP.";
break;
}
if (data.RectifyAttacks)
{
arpp.ATargetIP = arpp.ASenderIP;
arpp.ATargetMac = data.arpCache[arpp.ATargetIP];
arpp.ASenderMac = adapter.InterfaceInformation.GetPhysicalAddress().GetAddressBytes();
arpp.FromMac = arpp.ASenderMac;
arpp.ToMac = arpp.ATargetMac;
foreach (UnicastIPAddressInformation ipv4 in adapter.InterfaceInformation.GetIPProperties().UnicastAddresses)
{
if (ipv4.Address.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
{
arpp.ASenderIP = ipv4.Address;
break;
}
}
arpp.Outbound = true;
in_packet = arpp;
}
return pmra;
}
}
}
PacketMainReturn pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop;
if (data.LogUnsolic)
pmr.returnType |= PacketMainReturnType.Log;
switch (LanguageConfig.GetCurrentLanguage())
{
case LanguageConfig.Language.NONE:
case LanguageConfig.Language.ENGLISH:
pmr.logMessage = "Unsolicited ARP Response from " + new PhysicalAddress(arpp.ASenderMac).ToString() + " for " + arpp.ASenderIP.ToString();
break;
case LanguageConfig.Language.CHINESE:
pmr.logMessage = "未经请求的ARP应答为" + arpp.ASenderIP.ToString() + "从" + new PhysicalAddress(arpp.ASenderMac).ToString();
break;
case LanguageConfig.Language.GERMAN:
pmr.logMessage = "Initiativbewerbung ARP Response von " + new PhysicalAddress(arpp.ASenderMac).ToString() + " für " + arpp.ASenderIP.ToString();
break;
case LanguageConfig.Language.RUSSIAN:
pmr.logMessage = "Незапрошенные ответ ARP от " + new PhysicalAddress(arpp.ASenderMac).ToString() + " для " + arpp.ASenderIP.ToString();
break;
case LanguageConfig.Language.SPANISH:
pmr.logMessage = "Respuesta ARP no solicitados de " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString();
break;
case LanguageConfig.Language.PORTUGUESE:
pmr.logMessage = "Resposta ARP não solicitadas a partir de " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString();
break;
}
return pmr;
}
}
else
{
lock (padlock)
{
if (data.arpCache.ContainsKey(arpp.ASenderIP))
{
if (!Compare(data.arpCache[arpp.ASenderIP], arpp.ASenderMac))
{
PacketMainReturn pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop;
if (data.LogAttacks)
pmr.returnType |= PacketMainReturnType.Log | PacketMainReturnType.Popup;
switch (LanguageConfig.GetCurrentLanguage())
{
case LanguageConfig.Language.NONE:
case LanguageConfig.Language.ENGLISH:
pmr.logMessage = "ARP Response from " + new PhysicalAddress(arpp.ASenderMac).ToString() + " for " + arpp.ASenderIP.ToString() + " does not match the ARP cache.";
break;
case LanguageConfig.Language.CHINESE:
pmr.logMessage = new PhysicalAddress(arpp.ASenderMac).ToString() + "为" + arpp.ASenderIP.ToString() + "的ARP响应不匹配的ARP缓存。";
break;
case LanguageConfig.Language.GERMAN:
pmr.logMessage = "ARP Response von " + new PhysicalAddress(arpp.ASenderMac).ToString() + " für " + arpp.ASenderIP.ToString() + " nicht mit dem ARP-Cache.";
break;
case LanguageConfig.Language.RUSSIAN:
pmr.logMessage = "ARP-ответ от " + new PhysicalAddress(arpp.ASenderMac).ToString() + " для " + arpp.ASenderIP.ToString() + " не соответствует кэш ARP.";
break;
case LanguageConfig.Language.SPANISH:
pmr.logMessage = "Respuesta de ARP de " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " no coincide con la caché ARP.";
break;
case LanguageConfig.Language.PORTUGUESE:
pmr.logMessage = "Resposta da ARP " + new PhysicalAddress(arpp.ASenderMac).ToString() + " para " + arpp.ASenderIP.ToString() + " não coincide com o cache ARP.";
break;
}
return pmr;
}
}
}
}
return null;
}
return null;
}
return null;
}
// main routine
public override PacketMainReturn interiorMain(ref Packet in_packet)
{
PacketMainReturn pmr;
// check it the packet is, or contains, IP
if (in_packet.ContainsLayer(Protocol.IP))
{
// create a temp IPPacket obj and
// check the IP address
IPPacket temp = (IPPacket)in_packet;
if (!(isIPAllowed(temp.SourceIP)))
{
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop;
return pmr;
}
}
// simple sanity check to dump the ipcache if it gets too large.
// this does not effect the blockcache of banned IPs
if ((ipcache.Count) > 200)
ipcache.Clear();
// TCP incoming packets
if (in_packet.GetHighestLayer() == Protocol.TCP)
{
TCPPacket packet = ((TCPPacket)in_packet);
packet.PacketTime = DateTime.UtcNow;
// if it's inbound and the SYN flag is set
if (!packet.Outbound && packet.SYN && !packet.ACK)
{
// first packet init
if (TCPprevious_packet == null)
TCPprevious_packet = packet;
// if the IP hasn't been logged yet
if (!(ipcache.ContainsKey(packet.SourceIP)))
ipcache.Add(packet.SourceIP, 1);
// if the ipcache contains the ip
else if (ipcache.ContainsKey(packet.SourceIP))
{
// increment the packet count if they're coming in fast
if ((packet.PacketTime - TCPprevious_packet.PacketTime).TotalMilliseconds <= data.dos_threshold)
ipcache[packet.SourceIP] = (ipcache[packet.SourceIP]) + 1;
else ipcache[packet.SourceIP] = 1;
// check if this packet = previous, if the packet count is > 50,
// and if the time between sent packets is less than the threshhold
if (packet.SourceIP.Equals(TCPprevious_packet.SourceIP) &&
((ipcache[packet.SourceIP]) > 50) &&
(packet.PacketTime - TCPprevious_packet.PacketTime).TotalMilliseconds <= data.dos_threshold)
{
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop | PacketMainReturnType.Log | PacketMainReturnType.Popup;
pmr.logMessage = "DoS attempt detected from IP " + packet.SourceIP + " (likely spoofed). "
+ " Packets from this IP will be dropped. You can unblock this IP from the module interface.";
data.BlockCache.Add(new BlockedIP(packet.SourceIP, DateTime.UtcNow, "DoS Attempt"));
return pmr;
}
}
TCPprevious_packet = packet;
}
}
// fraggle attack mitigation
if (in_packet.GetHighestLayer() == Protocol.UDP)
{
UDPPacket packet = ((UDPPacket)in_packet);
packet.PacketTime = DateTime.UtcNow;
// if it's inbound
if (!(packet.Outbound))
{
// add IP to cache or increment packet count
if (!(ipcache.ContainsKey(packet.SourceIP)))
ipcache.Add(packet.SourceIP, 1);
else
ipcache[packet.SourceIP] = (ipcache[packet.SourceIP]) + 1;
// if the packet header is empty, headed towards port (7,13,19,17), and count > 50,
// then it's probably a fraggle attack
if (packet.isEmpty() && packet.DestPort.Equals(7) || packet.DestPort.Equals(13) ||
packet.DestPort.Equals(19) || packet.DestPort.Equals(17) &&
(ipcache[packet.SourceIP]) > 50)
{
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop | PacketMainReturnType.Log | PacketMainReturnType.Popup;
pmr.logMessage = "Potential fraggle attack from " + packet.SourceIP + " (likely spoofed). "
+ " Packets from this IP will be dropped. You can unblock this IP from the module interface.";
data.BlockCache.Add(new BlockedIP(packet.SourceIP, DateTime.UtcNow, "Fraggle Attempt"));
return pmr;
}
}
}
// smurf attack mitigation
if (in_packet.GetHighestLayer() == Protocol.ICMP)
{
ICMPPacket packet = ((ICMPPacket)in_packet);
packet.PacketTime = DateTime.UtcNow;
if (!(packet.Outbound))
{
// init the previous packet
if (ICMPprevious_packet == null)
ICMPprevious_packet = packet;
// add IP to cache or increment packet count
if (!(ipcache.ContainsKey(packet.SourceIP)))
ipcache.Add(packet.SourceIP, 1);
// if the packet is >= threshold after the previous and it's the same packet, clear up the cache
else if ((packet.PacketTime.Millisecond - ICMPprevious_packet.PacketTime.Millisecond) >= data.dos_threshold &&
packet.Equals(ICMPprevious_packet))
ipcache[packet.SourceIP] = 1;
// if the packet is coming in quickly, add it to the packet count
else if ((packet.PacketTime.Millisecond - ICMPprevious_packet.PacketTime.Millisecond) <= data.dos_threshold)
ipcache[packet.SourceIP] = (ipcache[packet.SourceIP]) + 1;
// if the packet is an echo reply and the IP source
// is the same as localhost and the time between packets is <= threshhold and
// there are over 50 accumulated packets, it's probably a smurf attack
if (packet.Type.ToString().Equals("0") &&
packet.Code.ToString().Equals("0") &&
packet.SourceIP.Equals(getLocalIP()) &&
(packet.PacketTime.Millisecond - ICMPprevious_packet.PacketTime.Millisecond) <= data.dos_threshold &&
ipcache[packet.SourceIP] > 50)
{
pmr = new PacketMainReturn(this);
pmr.returnType = PacketMainReturnType.Drop | PacketMainReturnType.Log | PacketMainReturnType.Popup;
pmr.logMessage = "Potential Smurf attack from " + packet.SourceIP + " (likely spoofed). "
+ " Packets from this IP will be dropped. You can unblock this IP from the module interface.";
data.BlockCache.Add(new BlockedIP(packet.SourceIP, DateTime.UtcNow, "Smurf Attempt"));
return pmr;
}
ICMPprevious_packet = packet;
}
}
return null;
}