/// <summary>
/// Parses an IP packet from the specified buffer at the given index, filtering according to the specified filters.
/// </summary>
/// <param name="buffer">The buffer.</param>
/// <param name="index">The index.</param>
/// <param name="length">The length.</param>
/// <param name="filters">The list of filters.</param>
/// <param name="packet">The IP packet or <b>null</b>.</param>
/// <returns><b>True</b> if th packet was parsed, <b>false</b> otherwise.</returns>
public static bool ParseFilter(byte[] buffer, ref int index, int length, FilterIp[] filters, out ProtoPacketIp packet)
{
// Set the packet to null.
packet = null;
// Validate the packet.
if (buffer[index] >> 4 != ProtoPacketIp.version) return false;
// Validate the length.
if ((ushort)((buffer[index + 2] << 8) | buffer[index + 3]) != length - index) return false;
// Set the protocol.
byte protocol = buffer[index + 9];
// Parse the source address.
IPAddress sourceAddress = new IPAddress(new byte[] { buffer[index + 12], buffer[index + 13], buffer[index + 14], buffer[index + 15] });
// Parse the destination address.
IPAddress destinationAddress = new IPAddress(new byte[] { buffer[index + 16], buffer[index + 17], buffer[index + 18], buffer[index + 19] });
// Try and match the filters.
bool match = false;
for (int idx = 0; (idx < filters.Length) && (!match); idx++)
{
match = match || filters[idx].Matches(sourceAddress, destinationAddress, protocol);
}
if (!match)
return false;
// Parse the packet.
packet = ProtoPacketIp.Parse(buffer, ref index, length);
// Return true.
return true;
}
/// <summary>
/// Creates a new payload packet instance.
/// </summary>
/// <param name="protocol">The protocol.</param>
public ProtoPacketIpPayload(ProtoPacketIp.Protocols protocol)
{
this.Protocol = protocol;
}
/// <summary>
/// Runs the traceroute using ICMP version 4.
/// </summary>
/// <param name="localEndPoint">The local end point.</param>
/// <param name="remoteEndPoint">The remote end point.</param>
/// <param name="socket">The sending socket.</param>
/// <param name="cancel">The cancellation token.</param>
/// <param name="result">The result.</param>
private void RunIcmpv4(IPEndPoint localEndPoint, IPEndPoint remoteEndPoint, Socket socket, CancellationToken cancel, MultipathTracerouteResult result)
{
// Set the packet processing delegate.
lock (this.syncProcess)
{
this.processPacket = this.ProcessPacketIcmp;
}
// The data payload.
byte[] data = new byte[this.settings.DataLength];
for (int index = 2; index < data.Length; index++)
{
data[index] = (byte)((index - 2) & 0xFF);
}
// Create an ICMP echo request packet.
ProtoPacketIcmpEchoRequest packetIcmpEchoRequest = new ProtoPacketIcmpEchoRequest(0, 0, data);
// Create an IP traceroute option.
//ProtoPacketIpOptionTraceroute packetIpOptionTraceroute = new ProtoPacketIpOptionTraceroute(0, 0, 0, localEndPoint.Address);
// Create an IP record route option.
//ProtoPacketIpOptionRecordRoute packetIpOptionRecordRoute = new ProtoPacketIpOptionRecordRoute(ProtoPacketIpOptionRecordRoute.maxSize);
// Create an IP version 4 packet.
ProtoPacketIp packetIp = new ProtoPacketIp(localEndPoint.Address, remoteEndPoint.Address, packetIcmpEchoRequest);
// Begin the ICMP measurements.
result.Callback(MultipathTracerouteState.StateType.BeginAlgorithm, MultipathAlgorithm.Icmp);
// For each attempt.
for (byte attempt = 0; attempt < settings.AttemptsPerFlow; attempt++)
{
// For each flow.
for (byte flow = 0; flow < result.Flows.Length; flow++)
{
// Call the start flow handler.
result.Callback(MultipathTracerouteState.StateType.BeginFlow, flow);
// Set the ICMP packet identifier.
packetIcmpEchoRequest.Identifier = result.Flows[flow].IcmpId;
for (byte retry = 0; (retry < this.settings.MaximumRetries) && (!result.IsIcmpDataComplete(flow, attempt)); retry++)
{
// If the retry is greater than zero, wait a random time.
if (retry > 0)
{
// Wait before beginning the next attempt.
Thread.Sleep(this.settings.RetryDelay);
}
// For each time-to-live.
for (byte ttl = this.settings.MinimumHops; ttl <= this.settings.MaximumHops; ttl++)
{
// If the response was received for this flow, TTL and attempt, skip.
if (result.IsIcmpDataResponseReceived(flow, ttl, attempt))
continue;
// Call the begin time-to-live.
result.Callback(MultipathTracerouteState.StateType.BeginTtl, ttl);
// Set the packet TTL.
packetIp.TimeToLive = ttl;
// Set the ICMP packet sequence number.
packetIcmpEchoRequest.Sequence = (ushort)((ttl << 8) | attempt);
// Compute the ICMP data to set the checksum.
int checksumDiff = (ushort)(~result.Flows[flow].IcmpChecksum & 0xFFFF) + ProtoPacket.ChecksumOneComplement16Bit(data, 2, data.Length - 2,
(ushort)((packetIcmpEchoRequest.Type << 8) | packetIcmpEchoRequest.Code),
packetIcmpEchoRequest.Identifier,
packetIcmpEchoRequest.Sequence);
checksumDiff = ((checksumDiff >> 16) + (checksumDiff & 0xFFFF)) & 0xFFFF;
// Set the data checksum difference.
data[0] = (byte)(checksumDiff >> 8);
data[1] = (byte)(checksumDiff & 0xFF);
// Write the packet to the buffer.
packetIp.Write(bufferSend, 0);
try
{
// Send a packet.
socket.SendTo(bufferSend, (int)packetIp.Length, SocketFlags.None, remoteEndPoint);
// Add the request.
MultipathTracerouteResult.RequestState state = result.AddRequest(MultipathTracerouteResult.RequestType.Icmp, flow, ttl, attempt, TimeSpan.FromMilliseconds(this.settings.HopTimeout));
// Set the data.
result.IcmpDataRequestSent(flow, ttl, attempt, state.Timestamp);
}
catch { }
// Call the end time-to-live.
result.Callback(MultipathTracerouteState.StateType.EndTtl, ttl);
}
}
// Call the end flow handler.
result.Callback(MultipathTracerouteState.StateType.EndFlow, flow);
// Wait before beginning the next attempt.
Thread.Sleep(this.settings.AttemptDelay);
}
}
// Wait for the result to complete.
result.Wait.WaitOne();
// Process the result statistics.
result.ProcessStatistics(MultipathTracerouteResult.ResultAlgorithm.Icmp);
// End the ICMP measurements.
result.Callback(MultipathTracerouteState.StateType.EndAlgorithm, MultipathAlgorithm.Icmp);
// Clear the packet processing delegate.
lock (this.syncProcess)
{
this.processPacket = null;
}
}
/// <summary>
/// Runs the traceroute using UDP over IP version 4.
/// </summary>
/// <param name="localEndPoint">The local end point.</param>
/// <param name="remoteEndPoint">The remote end point.</param>
/// <param name="socket">The sending socket.</param>
/// <param name="cancel">The cancellation token.</param>
/// <param name="result">The result.</param>
/// <param name="algorithm">The multipath algorithm.</param>
private void RunUdpv4(IPEndPoint localEndPoint, IPEndPoint remoteEndPoint, Socket socket, CancellationToken cancel, MultipathTracerouteResult result, MultipathAlgorithm algorithm)
{
// The request type.
MultipathTracerouteResult.RequestType requestType = MultipathTracerouteResult.RequestType.None;
if ((this.settings.Algorithm & MultipathAlgorithm.UdpType & MultipathAlgorithm.UdpIdentification) != 0)
{
// Set the request type.
requestType = requestType | MultipathTracerouteResult.RequestType.UdpIdentification;
}
if ((this.settings.Algorithm & MultipathAlgorithm.UdpType & MultipathAlgorithm.UdpChecksum) != 0)
{
// Set the request type.
requestType = requestType | MultipathTracerouteResult.RequestType.UdpChecksum;
}
if ((this.settings.Algorithm & MultipathAlgorithm.UdpTest) != 0)
{
// Set the request type.
requestType = MultipathTracerouteResult.RequestType.UdpBoth;
}
// Set the packet processing delegate
lock (this.syncProcess)
{
if ((requestType & MultipathTracerouteResult.RequestType.UdpIdentification) != 0)
this.processPacket = this.ProcessPacketUdpIdentification;
else
this.processPacket = this.ProcessPacketUdpChecksum;
}
// The data payload.
byte[] data = new byte[this.settings.DataLength];
for (int index = 2; index < data.Length; index++)
{
data[index] = (byte)((index - 2) & 0xFF);
}
// Create an UDP packet.
ProtoPacketUdp packetUdp = new ProtoPacketUdp(0, 0, data);
// Create an IP version 4 packet.
ProtoPacketIp packetIp = new ProtoPacketIp(localEndPoint.Address, remoteEndPoint.Address, packetUdp);
packetIp.DifferentiatedServices = 0x80;
// Begin the UDP measurements.
result.Callback(MultipathTracerouteState.StateType.BeginAlgorithm, algorithm);
// For each attempt.
for (byte attempt = 0; attempt < settings.AttemptsPerFlow; attempt++)
{
// For each flow.
for (byte flow = 0; flow < result.Flows.Length; flow++)
{
// Call the start flow handler.
result.Callback(MultipathTracerouteState.StateType.BeginFlow, flow);
// Set the UDP packet source port.
packetUdp.SourcePort = result.Flows[flow].UdpSourcePort;
// Set the UDP packet destination port.
packetUdp.DestinationPort = result.Flows[flow].UdpDestinationPort;
for (byte retry = 0; (retry < this.settings.MaximumRetries) && (!result.IsUdpDataComplete(flow, attempt)); retry++)
{
// If the retry is greater than zero, wait a random time.
if (retry > 0)
{
// Wait before beginning the next attempt.
Thread.Sleep(this.settings.RetryDelay);
}
// For each time-to-live.
for (byte ttl = this.settings.MinimumHops; ttl <= this.settings.MaximumHops; ttl++)
{
// If the response was received for this flow, TTL and attempt, skip.
if (result.IsUdpDataResponseReceived(flow, ttl, attempt))
continue;
// Call the begin time-to-live.
result.Callback(MultipathTracerouteState.StateType.BeginTtl, ttl);
// Set the packet TTL.
packetIp.TimeToLive = ttl;
if ((requestType & MultipathTracerouteResult.RequestType.UdpIdentification) != 0)
{
// Set the packet identification.
packetIp.Identification = (ushort)((ttl << 8) | attempt);
}
if ((requestType & MultipathTracerouteResult.RequestType.UdpChecksum) != 0)
{
// Compute the UDP data to set the checksum.
ushort checksum = (ushort)((ttl << 8) | attempt);
int checksumDiff = (ushort)(~checksum & 0xFFFF) + ProtoPacket.ChecksumOneComplement16Bit(data, 2, data.Length - 2,
packetUdp.SourcePort,
packetUdp.DestinationPort,
packetUdp.Length,
(ushort)((packetIp.SourceAddressBytes[0] << 8) | packetIp.SourceAddressBytes[1]),
(ushort)((packetIp.SourceAddressBytes[2] << 8) | packetIp.SourceAddressBytes[3]),
(ushort)((packetIp.DestinationAddressBytes[0] << 8) | packetIp.DestinationAddressBytes[1]),
(ushort)((packetIp.DestinationAddressBytes[2] << 8) | packetIp.DestinationAddressBytes[3]),
packetIp.Protocol,
packetUdp.Length);
checksumDiff = ((checksumDiff >> 16) + (checksumDiff & 0xFFFF)) & 0xFFFF;
// Set the data checksum difference.
data[0] = (byte)(checksumDiff >> 8);
data[1] = (byte)(checksumDiff & 0xFF);
}
// Write the packet to the buffer.
packetIp.Write(bufferSend, 0);
try
{
// Send a packet.
socket.SendTo(bufferSend, (int)packetIp.Length, SocketFlags.None, remoteEndPoint);
// Add the request.
MultipathTracerouteResult.RequestState state = result.AddRequest(MultipathTracerouteResult.RequestType.Udp, flow, ttl, attempt, TimeSpan.FromMilliseconds(this.settings.HopTimeout));
// Set the data.
result.UdpDataRequestSent(flow, ttl, attempt, state.Timestamp);
}
catch { }
// Call the end time-to-live.
result.Callback(MultipathTracerouteState.StateType.EndTtl, ttl);
}
}
// Call the end flow handler.
result.Callback(MultipathTracerouteState.StateType.EndFlow, flow);
// Wait before beginning the next attempt.
Thread.Sleep(this.settings.AttemptDelay);
}
}
// Wait for the result to complete.
result.Wait.WaitOne();
// Process the result statistics.
result.ProcessStatistics(MultipathTracerouteResult.ResultAlgorithm.Udp);
// End the UDP measurements.
result.Callback(MultipathTracerouteState.StateType.EndAlgorithm, algorithm);
// Clear the packet processing delegate.
lock (this.syncProcess)
{
this.processPacket = null;
}
}
/// <summary>
/// Processes a received packet for a UDP request using the checksum field.
/// </summary>
/// <param name="ip">The IP packet.</param>
/// <param name="length">The data length.</param>
/// <param name="result">The result.</param>
private void ProcessPacketUdpChecksum(ProtoPacketIp ip, int length, MultipathTracerouteResult result)
{
}
/// <summary>
/// Processes a received packet for a UDP request using the identification field.
/// </summary>
/// <param name="ip">The IP packet.</param>
/// <param name="length">The data length.</param>
/// <param name="result">The result.</param>
private void ProcessPacketUdpIdentification(ProtoPacketIp ip, int length, MultipathTracerouteResult result)
{
ProtoPacketIcmp icmp;
// If the packet payload is ICMP.
if ((icmp = ip.Payload as ProtoPacketIcmp) != null)
{
if (icmp.Type == (byte)ProtoPacketIcmp.IcmpType.TimeExceeded)
{
// If the packet type is ICMP time exceeded.
ProtoPacketIcmpTimeExceeded icmpTimeExceeded = icmp as ProtoPacketIcmpTimeExceeded;
// Use the last bytes of the UDP ports to find the flow.
ushort flowId = (ushort)((icmpTimeExceeded.IpPayload[1] << 8) | icmpTimeExceeded.IpPayload[3]);
byte flow;
if (result.TryGetUdpFlow(flowId, out flow))
{
// Get the time-to-live.
byte ttl = (byte)(icmpTimeExceeded.IpHeader.Identification >> 8);
// Get the attempt.
byte attempt = (byte)(icmpTimeExceeded.IpHeader.Identification & 0xF);
// Add the result.
result.UdpDataResponseReceived(flow, ttl, attempt, MultipathTracerouteData.ResponseType.TimeExceeded, DateTime.Now, ip);
// Remove the corresponding request.
result.RemoveRequest(MultipathTracerouteResult.RequestType.Udp, flow, ttl, attempt);
}
}
else if (icmp.Type == (byte)ProtoPacketIcmp.IcmpType.DestinationUnreachable)
{
// If the packet type is ICMP destination unreachable.
ProtoPacketIcmpDestinationUnreachable icmpDestinationUnreachable = icmp as ProtoPacketIcmpDestinationUnreachable;
// Check the message is a port unreachable.
if (icmpDestinationUnreachable.Code == (byte)ProtoPacketIcmpDestinationUnreachable.DestinationUnreachableCode.PortUnreachable)
{
// Use the last bytes of the UDP ports to find the flow.
ushort flowId = (ushort)((icmpDestinationUnreachable.IpPayload[1] << 8) | icmpDestinationUnreachable.IpPayload[3]);
byte flow;
if (result.TryGetUdpFlow(flowId, out flow))
{
// Get the time-to-live.
byte ttl = (byte)(icmpDestinationUnreachable.IpHeader.Identification >> 8);
// Get the attempt.
byte attempt = (byte)(icmpDestinationUnreachable.IpHeader.Identification & 0xF);
// Add the result.
result.UdpDataResponseReceived(flow, ttl, attempt, MultipathTracerouteData.ResponseType.DestinationUnreachable, DateTime.Now, ip);
// Remove the corresponding request.
result.RemoveRequest(MultipathTracerouteResult.RequestType.Udp, flow, ttl, attempt);
}
}
}
}
}
///// <summary>
///// Processes a received packet.
///// </summary>
///// <param name="buffer">The data buffer.</param>
///// <param name="length">The data length.</param>
///// <param name="result">The result.</param>
//private void ProcessPacket(byte[] buffer, int length, MultipathTracerouteResult result)
//{
// // Set the buffer index.
// int index = 0;
// // The packets.
// ProtoPacketIp ip;
// // Try and parse the packet using the specified filter.
// if (ProtoPacketIp.ParseFilter(buffer, ref index, length, result.PacketFilters, out ip))
// {
// // Call the callback methods.
// result.Callback(MultipathTracerouteState.StateType.PacketCapture, ip);
// // Process the packet for the current protocol.
// lock (this.syncProcess)
// {
// if (null != this.processPacket) this.processPacket(ip, length, result);
// }
// }
//}
/// <summary>
/// Processes a received packet for an ICMP request.
/// </summary>
/// <param name="ip">The IP packet.</param>
/// <param name="length">The data length.</param>
/// <param name="result">The result.</param>
private void ProcessPacketIcmp(ProtoPacketIp ip, int length, MultipathTracerouteResult result)
{
ProtoPacketIcmp icmp;
// If the packet payload is ICMP.
if ((icmp = ip.Payload as ProtoPacketIcmp) != null)
{
if (icmp.Type == (byte)ProtoPacketIcmp.IcmpType.EchoReply)
{
// If the packet type is ICMP echo reply.
ProtoPacketIcmpEchoReply icmpEchoReply = icmp as ProtoPacketIcmpEchoReply;
// Use the reply identifier to find the flow.
byte flow;
if (result.TryGetIcmpFlow(icmpEchoReply.Identifier, out flow))
{
// Get the time-to-live.
byte ttl = (byte)(icmpEchoReply.Sequence >> 8);
// Get the attempt.
byte attempt = (byte)(icmpEchoReply.Sequence & 0xFF);
// Add the result.
result.IcmpDataResponseReceived(flow, ttl, attempt, MultipathTracerouteData.ResponseType.EchoReply, DateTime.Now, ip);
// Remove the corresponding request.
result.RemoveRequest(MultipathTracerouteResult.RequestType.Icmp, flow, ttl, attempt);
}
}
else if (icmp.Type == (byte)ProtoPacketIcmp.IcmpType.TimeExceeded)
{
// If the packet type is ICMP time exceeded.
ProtoPacketIcmpTimeExceeded icmpTimeExceeded = icmp as ProtoPacketIcmpTimeExceeded;
// Use the ICMP request identifier to find the flow.
ushort flowId = (ushort)((icmpTimeExceeded.IpPayload[4] << 8) | icmpTimeExceeded.IpPayload[5]);
byte flow;
if (result.TryGetIcmpFlow(flowId, out flow))
{
// Get the time-to-live.
byte ttl = icmpTimeExceeded.IpPayload[6];
// Get the attempt.
byte attempt = icmpTimeExceeded.IpPayload[7];
// Add the result.
result.IcmpDataResponseReceived(flow, ttl, attempt, MultipathTracerouteData.ResponseType.TimeExceeded, DateTime.Now, ip);
// Remove the corresponding request.
result.RemoveRequest(MultipathTracerouteResult.RequestType.Icmp, flow, ttl, attempt);
}
}
}
}
///// <summary>
///// Requests a receiving buffer. The method blocks until a buffer is available or until the cancellation is requested.
///// </summary>
///// <param name="cancel">The cancellation token.</param>
///// <returns>The buffer index.</returns>
//private int RequestBuffer(CancellationToken cancel)
//{
// // The buffer index.
// int bufferIndex = -1;
// do
// {
// // Wait for a buffer to become available.
// this.bufferWait.WaitOne();
// lock (this.syncBuffer)
// {
// // If the buffer queue is not empty.
// if (this.bufferQueue.Count > 0)
// {
// // Get the first buffer index.
// bufferIndex = this.bufferQueue.Dequeue();
// // If the queue is empty, reset the buffer wait handle.
// if (this.bufferQueue.Count == 0) this.bufferWait.Reset();
// }
// }
// }
// while ((bufferIndex == -1) && (!cancel.IsCancellationRequested));
// // Return the buffer index.
// return bufferIndex;
//}
///// <summary>
///// Releases the specified buffer.
///// </summary>
///// <param name="bufferIndex">The buffer index.</param>
//private void ReleaseBuffer(int bufferIndex)
//{
// // Release the buffer.
// lock (this.syncBuffer)
// {
// // If the buffer queue is empty, set the buffer wait handle.
// if (this.bufferQueue.Count == 0) this.bufferWait.Set();
// // Add the buffer index to the queue.
// this.bufferQueue.Enqueue(bufferIndex);
// }
//}
///// <summary>
///// Receives a packet from the specified socket.
///// </summary>
///// <param name="socket">The socket.</param>
///// <param name="cancel">The cancellation token.</param>
///// <param name="result">The result.</param>
//private void ReceivePacket(Socket socket, CancellationToken cancel, MultipathTracerouteResult result)
//{
// // The remote end-point.
// EndPoint endPoint = new IPEndPoint(IPAddress.Any, 0);
// // Request a buffer.
// int bufferIndex = this.RequestBuffer(cancel);
// // If the operation was canceled, return.
// if (cancel.IsCancellationRequested) return;
// // Synchronization object.
// object localSync = new object();
// // Buffer flag.
// bool bufferFlag = true;
// try
// {
// // Begin receiving a packet.
// socket.BeginReceiveFrom(this.bufferRecv[bufferIndex], 0, this.bufferRecv[bufferIndex].Length, SocketFlags.None, ref endPoint, (IAsyncResult asyncResult) =>
// {
// lock (localSync)
// {
// try
// {
// // End receiving a packet.
// int length = socket.EndReceiveFrom(asyncResult, ref endPoint);
// // Process the packet.
// this.ProcessPacket(this.bufferRecv[bufferIndex], length, result);
// }
// catch (ObjectDisposedException) { }
// catch (Exception exception)
// {
// // Ignore all errors for received packets.
// result.Callback(MultipathTracerouteState.StateType.PacketError, exception);
// }
// finally
// {
// // If the buffer flag is set.
// if (bufferFlag)
// {
// // Release the buffer.
// this.ReleaseBuffer(bufferIndex);
// // Begin receiving the next packet.
// this.ReceivePacket(socket, cancel, result);
// // Set the flag to false.
// bufferFlag = false;
// }
// }
// }
// }, null);
// }
// catch (ObjectDisposedException) { }
// catch (Exception)
// {
// lock (localSync)
// {
// // If the buffer flag is set.
// if (bufferFlag)
// {
// // Release the buffer.
// this.ReleaseBuffer(bufferIndex);
// // Begin receiving the next packet.
// this.ReceivePacket(socket, cancel, result);
// // Set the flag to false.
// bufferFlag = false;
// }
// }
// }
//}
public void PacketReceiveSuccess(PacketCaptureHandler handler, byte[] buffer, int length, ProtoPacketIp ip)
{
MultipathTracerouteCaptureHandler tracerouteHandler = handler as MultipathTracerouteCaptureHandler;
// Call the callback methods.
tracerouteHandler.Result.Callback(MultipathTracerouteState.StateType.PacketCapture, ip);
// Process the packet for the current protocol.
lock (this.syncProcess)
{
if (null != this.processPacket) this.processPacket(ip, length, tracerouteHandler.Result);
}
}
public bool Matches(ProtoPacketIp ip)
{
// Try and match the filters.
bool match = false;
for (int idx = 0; (idx < filters.Length) && (!match); idx++)
{
match = match || filters[idx].Matches(ip);
}
return match;
}
public void Success(byte[] buffer, int length, ProtoPacketIp ip)
{
this.success(this, buffer, length, ip);
}
public bool Parse(byte[] buffer, ref int index, int length, out ProtoPacketIp ip)
{
return ProtoPacketIp.ParseFilter(buffer, ref index, length, this.filters, out ip);
}