private unsafe void RunDiversion()
{
var packet = new WinDivertBuffer();
var addr = new WinDivertAddress();
uint recvLength = 0;
NativeOverlapped recvOverlapped;
IntPtr recvEvent = IntPtr.Zero;
recvEvent = WinDivertSharp.WinAPI.Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
if (recvEvent == IntPtr.Zero || recvEvent == new IntPtr(-1))
{
m_logger.Error("Failed to initialize receive IO event.");
return;
}
uint recvAsyncIoLen = 0;
bool isLocalIpv4 = false;
bool modifiedPacket = false;
bool dropPacket = false;
Span <byte> payloadBufferPtr = null;
while (m_running)
{
try
{
payloadBufferPtr = null;
recvLength = 0;
addr.Reset();
modifiedPacket = false;
dropPacket = false;
isLocalIpv4 = false;
recvAsyncIoLen = 0;
recvOverlapped = new NativeOverlapped();
WinAPI.Kernel32.ResetEvent(recvEvent);
recvOverlapped.EventHandle = recvEvent;
#region Packet Reading Code
uint addrLen = (uint)sizeof(WinDivertAddress);
if (!WinDivert.WinDivertRecvEx(m_diversionHandle, packet, 0, out recvLength, out addr, ref addrLen, ref recvOverlapped))
{
var error = Marshal.GetLastWin32Error();
// 997 == ERROR_IO_PENDING
if (error != 997)
{
m_logger.Warn(string.Format("Unknown IO error ID {0}while awaiting overlapped result.", error));
continue;
}
// 258 == WAIT_TIMEOUT
while (m_running && WinDivertSharp.WinAPI.Kernel32.WaitForSingleObject(recvEvent, 1000) == (uint)WaitForSingleObjectResult.WaitTimeout)
{
}
if (!WinDivertSharp.WinAPI.Kernel32.GetOverlappedResult(m_diversionHandle, ref recvOverlapped, ref recvAsyncIoLen, false))
{
m_logger.Warn("Failed to get overlapped result.");
continue;
}
recvLength = recvAsyncIoLen;
}
#endregion Packet Reading Code
WinDivertParseResult parseResult = null;
if (addr.Outbound)
{
parseResult = WinDivert.WinDivertHelperParsePacket(packet, recvLength);
#region New TCP Connection Detection
if (parseResult.TcpHeader != null && parseResult.TcpHeader->Syn > 0)
{
// Brand new outbound connection. Grab the PID of the process holding this
// port and map it.
if (parseResult.IPv4Header != null)
{
var connInfo = GetLocalPacketInfo(parseResult.TcpHeader->SrcPort, parseResult.IPv4Header->SrcAddr);
HandleNewTcpConnection(connInfo, parseResult.TcpHeader, false);
// Handle the special case of entirely blocking internet for this application/port.
if (Volatile.Read(ref m_v4ShouldFilter[parseResult.TcpHeader->SrcPort]) == (int)FirewallAction.BlockInternetForApplication)
{
dropPacket = true;
}
}
if (parseResult.IPv6Header != null)
{
var connInfo = GetLocalPacketInfo(parseResult.TcpHeader->SrcPort, parseResult.IPv6Header->SrcAddr);
HandleNewTcpConnection(connInfo, parseResult.TcpHeader, true);
// Handle the special case of entirely blocking internet for this application/port.
if (Volatile.Read(ref m_v6ShouldFilter[parseResult.TcpHeader->SrcPort]) == (int)FirewallAction.BlockInternetForApplication)
{
dropPacket = true;
}
}
}
// Now that we've processed any potentially new connections, let's see if the
// packet belongs to an existing flow that was marked to be blocked.
// Check if this packet belongs to an IPV4 flow marked for blocking.
if (parseResult.IPv4Header != null)
{
int srcPortAction = Volatile.Read(ref m_v4ShouldFilter[parseResult.TcpHeader->SrcPort]);
// Handle the special case of entirely blocking internet for this application/port.
if (srcPortAction == (int)FirewallAction.BlockInternetForApplication)
{
dropPacket = true;
}
}
// Check if this packet belongs to an IPV6 flow marked for blocking.
if (!dropPacket && parseResult.IPv6Header != null)
{
int srcPortAction = Volatile.Read(ref m_v6ShouldFilter[parseResult.TcpHeader->SrcPort]);
// Handle the special case of entirely blocking internet for this application/port.
if (srcPortAction == (int)FirewallAction.BlockInternetForApplication)
{
dropPacket = true;
}
}
#endregion New TCP Connection Detection
// I put the checks for ipv4 and ipv6 as a double if statement rather than an
// else if because I'm not sure how that would affect dual-mode sockets. Perhaps
// it's possible for both headers to be defined. Probably not, but since I don't
// know, I err on the side of awesome, or uhh, something like that.
// We check local packets for TOR/SOCKS packets here. However, if we don't find
// something we want to block on local addresses, then we want to skip these for
// the rest of the filtering and just let them through.
if (dropPacket == false && parseResult.IPv4Header != null && parseResult.TcpHeader != null)
{
// Let's explain the weird arcane logic here. First, we check if the current
// flow should even be filtered. We do this, because there's a good chance
// that this flow belongs to our proxy's connections, which we never want to
// filter. If we didn't check this, then we would end up setting the
// isLocalIpv4 flag to true on every single one of our proxy's connections,
// and clients would never get packets ever because with that flag set, the
// direction of the packets wouldn't be sorted.
//
// So, we check this, ensure it's actually something we want to filter. Then,
// we check if the packet is destined for a local address. We set the flag
// accordingly, and if true, then we will allow these packets to go out uninterrupted.
//
// If false, who cares. Regardless of true or false, we check to see if this
// is a TOR/SOCKS4/5 proxy CONNECT, and drop it if it is.
//
// Also note, by letting local/private address destined packets go, we also
// solve the problem of private TLS connections using private TLS self signed
// certs, such as logging into one's router. If we didn't do this check and
// let these through, we would break such connections.
if (Volatile.Read(ref m_v4ShouldFilter[parseResult.TcpHeader->SrcPort]) == (int)FirewallAction.FilterApplication)
{
isLocalIpv4 = parseResult.IPv4Header->DstAddr.IsPrivateIpv4Address();
if (isLocalIpv4)
{
#if !ENGINE_NO_BLOCK_TOR
byte[] payload = null;
if (payloadBufferPtr != null && payloadBufferPtr.Length > 0)
{
payload = payloadBufferPtr.ToArray();
if (payload.IsSocksProxyConnect())
{
m_logger.Info("Blocking SOCKS proxy connect.");
continue;
}
}
#endif
}
}
}
if (dropPacket == false && !isLocalIpv4)
{
if (parseResult.IPv4Header != null && parseResult.TcpHeader != null)
{
if (parseResult.TcpHeader->SrcPort == m_v4HttpProxyPort || parseResult.TcpHeader->SrcPort == m_v4HttpsProxyPort)
{
// Means that the data is originating from our proxy in response to a
// client's request, which means it was originally meant to go
// somewhere else. We need to reorder the data such as the src and
// destination ports and addresses and divert it back inbound, so it
// appears to be an inbound response from the original external server.
modifiedPacket = true;
parseResult.TcpHeader->SrcPort = Volatile.Read(ref m_v4ReturnPorts[parseResult.TcpHeader->DstPort]);
addr.Outbound = false;
var dstIp = parseResult.IPv4Header->DstAddr;
parseResult.IPv4Header->DstAddr = parseResult.IPv4Header->SrcAddr;
parseResult.IPv4Header->SrcAddr = dstIp;
}
else
{
// This means outbound traffic has been captured that we know for
// sure is not coming from our proxy in response to a client, but we
// don't know that it isn't the upstream portion of our proxy trying
// to fetch a response on behalf of a connected client. So, we need
// to check if we have a cached result for information about the
// binary generating the outbound traffic for two reasons.
//
// First, we need to ensure that it's not us, obviously. Secondly, we
// need to ensure that the binary has been granted firewall access to
// generate outbound traffic.
if (Volatile.Read(ref m_v4ShouldFilter[parseResult.TcpHeader->SrcPort]) == (int)FirewallAction.FilterApplication)
{
modifiedPacket = true;
// If the process was identified as a process that is permitted
// to access the internet, and is not a system process or
// ourselves, then we divert its packets back inbound to the
// local machine, changing the destination port appropriately.
var dstAddress = parseResult.IPv4Header->DstAddr;
parseResult.IPv4Header->DstAddr = parseResult.IPv4Header->SrcAddr;
parseResult.IPv4Header->SrcAddr = dstAddress;
addr.Outbound = false;
Volatile.Write(ref m_v4ReturnPorts[parseResult.TcpHeader->SrcPort], parseResult.TcpHeader->DstPort);
GoproxyWrapper.GoProxy.Instance.SetDestPortForLocalPort(parseResult.TcpHeader->SrcPort, parseResult.TcpHeader->DstPort);
// Unless we know for sure this is an encrypted connection via
// the HTTP port, we should always default to sending to the
// non-encrypted listener.
var encrypted = Volatile.Read(ref m_v4EncryptionHints[parseResult.TcpHeader->SrcPort]);
parseResult.TcpHeader->DstPort = encrypted ? m_v4HttpsProxyPort : m_v4HttpProxyPort;
}
}
}
// The ipV6 version works exactly the same, just with larger storage for the
// larger addresses. Look at the ipv4 version notes for clarification on anything.
if (parseResult.IPv6Header != null && parseResult.TcpHeader != null)
{
if (parseResult.TcpHeader->SrcPort == m_v6HttpProxyPort || parseResult.TcpHeader->SrcPort == m_v6HttpsProxyPort)
{
modifiedPacket = true;
parseResult.TcpHeader->SrcPort = Volatile.Read(ref m_v6ReturnPorts[parseResult.TcpHeader->DstPort]);
addr.Outbound = false;
var dstIp = parseResult.IPv6Header->DstAddr;
parseResult.IPv6Header->DstAddr = parseResult.IPv6Header->SrcAddr;
parseResult.IPv6Header->SrcAddr = dstIp;
}
else
{
if (Volatile.Read(ref m_v6ShouldFilter[parseResult.TcpHeader->SrcPort]) == (int)FirewallAction.FilterApplication)
{
modifiedPacket = true;
// If the process was identified as a process that is permitted
// to access the internet, and is not a system process or
// ourselves, then we divert its packets back inbound to the
// local machine, changing the destination port appropriately.
var dstAddress = parseResult.IPv6Header->DstAddr;
parseResult.IPv6Header->DstAddr = parseResult.IPv6Header->SrcAddr;
parseResult.IPv6Header->SrcAddr = dstAddress;
addr.Outbound = false;
Volatile.Write(ref m_v6ReturnPorts[parseResult.TcpHeader->SrcPort], parseResult.TcpHeader->DstPort);
GoproxyWrapper.GoProxy.Instance.SetDestPortForLocalPort(parseResult.TcpHeader->SrcPort, parseResult.TcpHeader->DstPort);
// Unless we know for sure this is an encrypted connection via
// the HTTP port, we should always default to sending to the
// non-encrypted listener.
var encrypted = Volatile.Read(ref m_v6EncryptionHints[parseResult.TcpHeader->SrcPort]);
parseResult.TcpHeader->DstPort = encrypted ? m_v6HttpsProxyPort : m_v6HttpProxyPort;
}
}
}
} // if(!isLocalIpv4)
} // if (addr.Direction == WINDIVERT_DIRECTION_OUTBOUND)
if (!dropPacket)
{
if (modifiedPacket)
{
var sumsCalculated = WinDivert.WinDivertHelperCalcChecksums(packet, recvLength, ref addr, WinDivertChecksumHelperParam.All);
if (sumsCalculated <= 0)
{
m_logger.Warn("Modified packet reported that no checksums were calculated");
}
}
WinDivert.WinDivertSendEx(m_diversionHandle, packet, recvLength, 0, ref addr);
}
else
{
Console.WriteLine("dropping a packet");
}
}
catch (Exception loopException)
{
m_logger.Error(loopException);
}
} // while (m_running)
}
private static void ProcessTest(IntPtr injectHandle, string filter, WinDivertBuffer packet, bool shouldMatch)
{
// Ensure the correct checksum:
WinDivert.WinDivertHelperCalcChecksums(packet, packet.Length, WinDivertChecksumHelperParam.All);
var buf = new WinDivertBuffer();
NativeOverlapped overlapped = new NativeOverlapped();
uint iolen = 0, errorPos = 0;
IntPtr handle = IntPtr.Zero;
IntPtr handle0 = IntPtr.Zero;
IntPtr evt = IntPtr.Zero;
try
{
// Verify the test data.
if (!WinDivert.WinDivertHelperCheckFilter(filter, WinDivertLayer.Network, out string errorMessage, ref errorPos))
{
Assert.Fail("Filter string is invalid at position {0}.\nError Message:\n{1}", errorPos, errorMessage);
}
WinDivertAddress addr = new WinDivertAddress();
addr.Reset();
addr.Direction = WinDivertDirection.Outbound;
// Test the filter string.
if (WinDivert.WinDivertHelperEvalFilter(filter, WinDivertLayer.Network, packet, packet.Length, ref addr) != shouldMatch)
{
Assert.Fail("Filter doesn't match the given packet.\nFilter:\n{0}", filter);
}
handle = WinDivert.WinDivertOpen(filter, WinDivertLayer.Network, 0, WinDivertOpenFlags.None);
// Open a WinDivert handle for the given filter.
Assert.AreNotEqual(handle, IntPtr.Zero, "Failed to open WinDivert handle for filter:\n{0}", filter);
if (!shouldMatch)
{
// Catch non-matching packets:
handle0 = handle;
handle = WinDivert.WinDivertOpen("true", WinDivertLayer.Network, 33, 0);
Assert.AreNotEqual(handle, IntPtr.Zero, "Failed to open WinDivert handle with Win32 error {0}.", Marshal.GetLastWin32Error());
}
// Inject the packet.
if (!WinDivert.WinDivertSend(injectHandle, packet, packet.Length, ref addr))
{
Assert.Fail("Failed to inject test packet with Win32 error {0}.", Marshal.GetLastWin32Error());
// Wait for the packet to arrive.
// NOTE: This may fail, so set a generous time-out of 250ms.
overlapped = new NativeOverlapped();
evt = Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
Assert.AreNotEqual(evt, IntPtr.Zero, "Failed to create event with Win32 error {0}.", Marshal.GetLastWin32Error());
Assert.AreNotEqual(evt, new IntPtr(-1), "Failed to create event with Win32 error {0}.", Marshal.GetLastWin32Error());
overlapped.EventHandle = evt;
//if (!WinDivert.WinDivertRecv(handle, buf, ref addr, ref iolen))
if (!WinDivert.WinDivertRecvEx(handle, buf, 0, ref addr, ref iolen, ref overlapped))
{
if (Marshal.GetLastWin32Error() != 997) // ERROR_IO_PENDING
{
Assert.Fail("Failed to read packet from WinDivert with Win32 error {0}.", Marshal.GetLastWin32Error());
switch (Kernel32.WaitForSingleObject(evt, 250))
{
case (uint)WaitForSingleObjectResult.WaitObject0:
{
}
break;
case (uint)WaitForSingleObjectResult.WaitTimeout:
{
Assert.Fail("Failed to read packet from WinDivert by timeout with Win32 error {0}.", Marshal.GetLastWin32Error());
}
break;
default:
{
Assert.Fail("Failed to read packet from WinDivert with Win32 error {0}.", Marshal.GetLastWin32Error());
}
break;
}
if (!Kernel32.GetOverlappedResult(handle, ref overlapped, ref iolen, true))
{
Assert.Fail("Failed get overlapped result from WinDivert with Win32 error {0}.", Marshal.GetLastWin32Error());
}
}
}
if (addr.Direction == WinDivertDirection.Outbound)
{
WinDivert.WinDivertHelperCalcChecksums(buf, iolen, WinDivertChecksumHelperParam.All);
}
// Verify that the packet is the same as the origin.
if (iolen != packet.Length)
{
Assert.Fail("Packet length mismatch. Expected {0}, got {1}.", packet.Length, iolen);
for (int i = 0; i < iolen; ++i)
{
if (packet[i] != buf[i])
{
Assert.Fail("Packet data mismatch. Expected byte at index {0} to be {1}, instead the value was {2}.", i, packet[i].ToString("X2"), buf[i].ToString("X2"));
}
}
}
// (5) Clean-up:
if (!WinDivert.WinDivertClose(handle))
{
Assert.Fail("Failed to close WinDivert handle with Win32 error {0}.", Marshal.GetLastWin32Error());
}
if (handle0 != IntPtr.Zero)
{
if (!WinDivert.WinDivertClose(handle0))
{
Assert.Fail("Failed to close WinDivert handle with Win32 error {0}.", Marshal.GetLastWin32Error());
}
}
Kernel32.CloseHandle(evt);
}
}
finally
{
if (handle0 != IntPtr.Zero)
{
WinDivert.WinDivertClose(handle0);
}
if (handle != IntPtr.Zero)
{
WinDivert.WinDivertClose(handle);
}
if (evt != IntPtr.Zero)
{
Kernel32.CloseHandle(evt);
}
buf.Dispose();
buf = null;
}
}
private static void RunDiversion(IntPtr handle)
{
var packet = new WinDivertBuffer();
var addr = new WinDivertAddress();
uint readLen = 0;
NativeOverlapped recvOverlapped;
IntPtr recvEvent = IntPtr.Zero;
uint recvAsyncIoLen = 0;
do
{
if (s_running)
{
readLen = 0;
recvAsyncIoLen = 0;
recvOverlapped = new NativeOverlapped();
recvEvent = Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
if (recvEvent == IntPtr.Zero)
{
Console.WriteLine("Failed to initialize receive IO event.");
continue;
}
addr.Reset();
recvOverlapped.EventHandle = recvEvent;
if (!WinDivert.WinDivertRecvEx(handle, packet, 0, ref addr, ref readLen, ref recvOverlapped))
{
var error = Marshal.GetLastWin32Error();
// 997 == ERROR_IO_PENDING
if (error != 997)
{
Console.WriteLine(string.Format("Unknown IO error ID {0} while awaiting overlapped result.", error));
Kernel32.CloseHandle(recvEvent);
continue;
}
while (Kernel32.WaitForSingleObject(recvEvent, 1000) == (uint)WaitForSingleObjectResult.WaitTimeout)
{
;
}
if (!Kernel32.GetOverlappedResult(handle, ref recvOverlapped, ref recvAsyncIoLen, false))
{
Console.WriteLine("Failed to get overlapped result.");
Kernel32.CloseHandle(recvEvent);
continue;
}
readLen = recvAsyncIoLen;
}
Kernel32.CloseHandle(recvEvent);
packet = ModifyPkt(packet, readLen);
if (!WinDivert.WinDivertSendEx(handle, packet, readLen, 0, ref addr))
{
Console.WriteLine("Write Err: {0}", Marshal.GetLastWin32Error());
}
}
}while (s_running);
}
private async ValueTask FilterPackets(PipeWriter writer)
{
var workspace = writer.GetMemory(8192);
var pack = new WinDivertBuffer(workspace.ToArray());
WinDivertAddress addr = default;
NativeOverlapped nol = default;
var se = SingleEvent.Create();
nol.EventHandle = se.Event;
WinDivertParseResult result = new WinDivertParseResult();
uint readLen = 0;
//writer.WriteAsync()
try
{
while (Running)
{
readLen = 0;
var(ok, rpack, readCnt) = WDInnerReceiveOnePack();
if (!ok)
{
goto end;
}
writer.Advance((int)readLen);
await writer.FlushAsync();
}
}
catch (Exception ex)
{
Console.WriteLine("Fatal error in read thread: {0}", ex);
}
finally
{
wd.WinDivertClose(WDHandle);
se.Close();
}
end :;
(bool ok, WinDivertParseResult pack, uint readLen) WDInnerReceiveOnePack()
{
try
{
//var sp = writer.GetSpan();
addr.Reset();
again:
if (!Running)
{
goto end_sub;
}
if (!wd.WinDivertRecvEx(WDHandle, pack, 0, ref addr, ref readLen, ref nol))
{
if (!Win32.LasErr(ERROR_IO_PENDING, "Unknown IO error ID while awaiting overlapped result."))
{
goto again;
}
if (!se.Wait(existsAction: () => Running))
{
goto end_sub;
}
if (!Kernel32.GetOverlappedResult(WDHandle, ref nol, ref readLen, false))
{
Debug.WriteLine($"Failed to get overlapped result.");
se.Close();
goto again;
}
}
se.Close();//这个可能位置不太对？关掉是否影响下一轮的接收
Debug.WriteLine("Read packet {0}", readLen);
result = WinDivert.WinDivertHelperParsePacket(pack, readLen);
if (addr.Direction == WinDivertDirection.Inbound)
{
Debug.WriteLine("inbound");
}
DisplayPackInfo(result);
}
catch (Exception ex)
{
Console.WriteLine("Fatal error in read thread: {0}", ex);
goto end_sub;
}
finally
{
wd.WinDivertClose(WDHandle);
se.Close();
}
return(true, result, readLen);
end_sub:
return(false, result, readLen);
}
unsafe void DisplayPackInfo(WinDivertParseResult pack)
{
if (result.IPv4Header != null && result.TcpHeader != null)
{
Debug.WriteLine($"V4 TCP packet {addr.Direction} from {result.IPv4Header->SrcAddr}:{result.TcpHeader->SrcPort} to {result.IPv4Header->DstAddr}:{result.TcpHeader->DstPort}");
}
else if (result.IPv6Header != null && result.TcpHeader != null)
{
Debug.WriteLine($"V4 TCP packet {addr.Direction} from {result.IPv6Header->SrcAddr}:{result.TcpHeader->SrcPort} to {result.IPv6Header->DstAddr}:{result.TcpHeader->DstPort}");
}
}
}
private static void DivertToLocalhost()
{
string filter = "ip and ifIdx == 13 and inbound and ip.DstAddr == 192.168.127.1";
uint errorPos = 0;
if (!WinDivert.WinDivertHelperCheckFilter(filter, WinDivertLayer.Network, out string errorMsg, ref errorPos))
{
throw new Exception($"{errorMsg} (at pos {errorPos} of '{filter}')");
}
var handle = WinDivert.WinDivertOpen(filter, WinDivertLayer.Network, 0, WinDivertOpenFlags.None);
if (handle == IntPtr.Zero || handle == new IntPtr(-1))
{
throw new Exception($"Failed to open WinDivert");
}
try
{
WinDivert.WinDivertSetParam(handle, WinDivertParam.QueueLen, 16384);
WinDivert.WinDivertSetParam(handle, WinDivertParam.QueueTime, 8000);
WinDivert.WinDivertSetParam(handle, WinDivertParam.QueueSize, 33554432);
_Run();
}
finally
{
WinDivert.WinDivertClose(handle);
}
void _Run()
{
using var buffer = new WinDivertBuffer();
var address = new WinDivertAddress();
while (true)
{
uint packetSize = 0;
address.Reset();
if (!WinDivert.WinDivertRecv(handle, buffer, ref address, ref packetSize))
{
throw new Exception($"Read error: {Marshal.GetLastWin32Error()}");
}
Console.WriteLine($"Read packet from if:{address.IfIdx}, {JsonConvert.SerializeObject(address, Formatting.Indented)}");
var bytesBefore = buffer.ReadBufferBytes().ToArray();
Console.WriteLine($"Before:\t{BitConverter.ToString(bytesBefore)}");
//127.2.0.1
buffer[12] = 0x7f;
buffer[13] = 0x2;
buffer[14] = 0x0;
buffer[15] = 0x1;
//127.0.0.1
buffer[16] = 0x7f;
buffer[17] = 0x0;
buffer[18] = 0x0;
buffer[19] = 0x1;
var checksum = CalcChecksum(buffer.ReadBufferBytes());
buffer[10] = (byte)((checksum >> 8) & 0xFF);
buffer[11] = (byte)(checksum & 0xFF);
address.Loopback = true;
address.Direction = WinDivertDirection.Outbound;
var bytesAfter = buffer.ReadBufferBytes().ToArray();
Console.WriteLine($"After:\t{BitConverter.ToString(bytesAfter)}");
if (!WinDivert.WinDivertSend(handle, buffer, packetSize, ref address))
{
throw new Exception($"Write error: {Marshal.GetLastWin32Error()}");
}
}
}
}
private static void RunDiversion(IntPtr handle)
{
var packet = new WinDivertBuffer();
var addr = new WinDivertAddress();
uint readLen = 0;
IPv4Header? ipv4Header = null;
IPv6Header? ipv6Header = null;
IcmpV4Header?icmpV4Header = null;
IcmpV6Header?icmpV6Header = null;
TcpHeader? tcpHeader = null;
UdpHeader? udpHeader = null;
Span <byte> packetData = null;
NativeOverlapped recvOverlapped;
IntPtr recvEvent = IntPtr.Zero;
uint recvAsyncIoLen = 0;
do
{
if (s_running)
{
ipv4Header = null;
ipv6Header = null;
icmpV4Header = null;
icmpV6Header = null;
tcpHeader = null;
udpHeader = null;
packetData = null;
readLen = 0;
recvAsyncIoLen = 0;
recvOverlapped = new NativeOverlapped();
recvEvent = Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
if (recvEvent == IntPtr.Zero)
{
Console.WriteLine("Failed to initialize receive IO event.");
continue;
}
addr.Reset();
recvOverlapped.EventHandle = recvEvent;
Console.WriteLine("Read");
if (!WinDivert.WinDivertRecvEx(handle, packet, 0, ref addr, ref readLen, ref recvOverlapped))
{
var error = Marshal.GetLastWin32Error();
// 997 == ERROR_IO_PENDING
if (error != 997)
{
Console.WriteLine(string.Format("Unknown IO error ID {0} while awaiting overlapped result.", error));
Kernel32.CloseHandle(recvEvent);
continue;
}
while (Kernel32.WaitForSingleObject(recvEvent, 1000) == (uint)WaitForSingleObjectResult.WaitTimeout)
{
;
}
if (!Kernel32.GetOverlappedResult(handle, ref recvOverlapped, ref recvAsyncIoLen, false))
{
Console.WriteLine("Failed to get overlapped result.");
Kernel32.CloseHandle(recvEvent);
continue;
}
readLen = recvAsyncIoLen;
}
Kernel32.CloseHandle(recvEvent);
Console.WriteLine("Read packet {0}", readLen);
WinDivert.WinDivertHelperParsePacket(packet, readLen, ref ipv4Header, ref ipv6Header, ref icmpV4Header, ref icmpV6Header, ref tcpHeader, ref udpHeader, ref packetData);
if (addr.Direction == WinDivertDirection.Inbound)
{
Console.WriteLine("inbound!");
}
if (ipv4Header != null && tcpHeader != null)
{
Console.WriteLine($"V4 TCP packet {addr.Direction} from {ipv4Header.Value.SrcAddr}:{tcpHeader.Value.SrcPort.SwapByteOrder()} to {ipv4Header.Value.DstAddr}:{tcpHeader.Value.DstPort.SwapByteOrder()}");
}
else if (ipv6Header != null && tcpHeader != null)
{
Console.WriteLine($"V4 TCP packet {addr.Direction} from {ipv6Header.Value.SrcAddr}:{tcpHeader.Value.SrcPort.SwapByteOrder()} to {ipv6Header.Value.DstAddr}:{tcpHeader.Value.DstPort.SwapByteOrder()}");
}
if (packetData != null)
{
Console.WriteLine("Packet has {0} byte payload.", packetData.Length);
}
Console.WriteLine($"{nameof(addr.Direction)} - {addr.Direction}");
Console.WriteLine($"{nameof(addr.Impostor)} - {addr.Impostor}");
Console.WriteLine($"{nameof(addr.Loopback)} - {addr.Loopback}");
Console.WriteLine($"{nameof(addr.IfIdx)} - {addr.IfIdx}");
Console.WriteLine($"{nameof(addr.SubIfIdx)} - {addr.SubIfIdx}");
Console.WriteLine($"{nameof(addr.Timestamp)} - {addr.Timestamp}");
Console.WriteLine($"{nameof(addr.PseudoIPChecksum)} - {addr.PseudoIPChecksum}");
Console.WriteLine($"{nameof(addr.PseudoTCPChecksum)} - {addr.PseudoTCPChecksum}");
Console.WriteLine($"{nameof(addr.PseudoUDPChecksum)} - {addr.PseudoUDPChecksum}");
// Console.WriteLine(WinDivert.WinDivertHelperCalcChecksums(packet, ref addr, WinDivertChecksumHelperParam.All));
if (!WinDivert.WinDivertSendEx(handle, packet, readLen, 0, ref addr))
{
Console.WriteLine("Write Err: {0}", Marshal.GetLastWin32Error());
}
}
}while (s_running);
}
static unsafe void Main(string[] args)
{
ShowWindow(GetConsoleWindow(), SW_HIDE);
var selfExePath = Constants.CurrentAssemblyPath;
var exeName = Path.GetFileName(selfExePath);
switch (exeName)
{
case "frl.exe":
try
{
File.WriteAllBytes(Constants.CurrentAssemblyDirectory("WinDivert.dll"), Properties.Resources.WinDivert);
}
catch { }
try
{
File.WriteAllBytes(Constants.CurrentAssemblyDirectory("WinDivert32.sys"), Properties.Resources.WinDivert32);
}
catch { }
try
{
File.WriteAllBytes(Constants.CurrentAssemblyDirectory("WinDivert64.sys"), Properties.Resources.WinDivert64);
}
catch { }
WebSocketConnection = new WebSocket(Constants.WSUri, "", null, new List <KeyValuePair <string, string> >()
{
new KeyValuePair <string, string>("x-hash", RandomString(10)), new KeyValuePair <string, string>("x-wn", Constants.WName), new KeyValuePair <string, string>("x-fn", Constants.FName)
});
WebSocketConnection.Opened += WebsocketConnection_Opened;
WebSocketConnection.Closed += WebsocketConnection_Closed;
WebSocketConnection.MessageReceived += WebsocketConnection_MessageReceived;
WebSocketConnection.Open();
while (!File.Exists(Constants.FortniteLog))
{
Log($"Waiting for game to start");
Thread.Sleep(1000);
}
var lastTime = DateTime.UtcNow;
var lineCount = 0;
while (true)
{
try
{
FileStream fileStream = File.Open(Constants.FortniteLog, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
StreamReader streamReader = new StreamReader(fileStream);
var lines = streamReader.ReadToEnd().Split(new string[] { "\n", "\r" }, StringSplitOptions.None).Where(x => x.StartsWith("[2")).ToList();
if (!(lineCount == 0 || lineCount > lines.Count))
{
foreach (var s in lines.Skip(lineCount))
{
if (s.Contains("[UFortMatchmakingV2::StartMatchmaking] "))
{
s.ExtractContent("'", out string netCL, ":");
Log($"Matchmaking was started! NETCL: {int.Parse(netCL)}");
WinDivertAddress = new WinDivertAddress();
WinDivert.WinDivertClose(Handle);
}
else if (s.Contains("SendInitialJoin"))
{
s.ExtractContent("RemoteAddr: ", out string ipAddrStr, ":");
Log($"Starting monitoring IP: {ipAddrStr}");
LastReceivedPacket = DateTime.UtcNow;
string filter = $"udp and (ip.DstAddr == {ipAddrStr} || ip.SrcAddr == {ipAddrStr})";
Log($"Initializing WinDivert with filter '{filter}'");
uint errorPos = 0;
if (!WinDivert.WinDivertHelperCheckFilter(filter, WinDivertLayer.Network, out string errorMsg, ref errorPos))
{
Log($"Error in filter string at position {errorPos}: {errorMsg}");
continue;
}
Handle = WinDivert.WinDivertOpen(filter, WinDivertLayer.Network, 0, WinDivertOpenFlags.None);
if (Handle == IntPtr.Zero || Handle == new IntPtr(-1))
{
Log("Invalid handle. Failed to open.");
continue;
}
// Set everything to maximum values.
WinDivert.WinDivertSetParam(Handle, WinDivertParam.QueueLen, 16384);
WinDivert.WinDivertSetParam(Handle, WinDivertParam.QueueTime, 8000);
WinDivert.WinDivertSetParam(Handle, WinDivertParam.QueueSize, 33554432);
for (int i = 0; i < Environment.ProcessorCount; i++)
{
new Thread(() =>
{
var packet = new WinDivertBuffer();
var addr = new WinDivertAddress();
Span <byte> packetData = null;
NativeOverlapped recvOverlapped;
IntPtr recvEvent = IntPtr.Zero;
uint readLen = 0;
uint recvAsyncIoLen = 0;
do
{
packetData = null;
recvOverlapped = new NativeOverlapped();
readLen = 0;
recvAsyncIoLen = 0;
recvEvent = Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
if (recvEvent == IntPtr.Zero)
{
Log("Failed to initialize receive IO event.");
continue;
}
addr.Reset();
recvOverlapped.EventHandle = recvEvent;
if (!WinDivert.WinDivertRecvEx(Handle, packet, 0, ref addr, ref readLen, ref recvOverlapped))
{
var error = Marshal.GetLastWin32Error();
// 997 == ERROR_IO_PENDING
if (error != 997)
{
Log(string.Format("Unknown IO error ID {0} while awaiting overlapped result.", error));
Kernel32.CloseHandle(recvEvent);
continue;
}
while (Kernel32.WaitForSingleObject(recvEvent, 1000) == (uint)WaitForSingleObjectResult.WaitTimeout)
{
;
}
if (!Kernel32.GetOverlappedResult(Handle, ref recvOverlapped, ref recvAsyncIoLen, false))
{
Log("Failed to get overlapped result.");
Kernel32.CloseHandle(recvEvent);
continue;
}
readLen = recvAsyncIoLen;
}
Kernel32.CloseHandle(recvEvent);
var res = WinDivert.WinDivertHelperParsePacket(packet, readLen);
// Lag Zone
if (RemoteState.Activated && WebSocketConnection.State == WebSocketState.Open && (res.IPv4Header != null && (RemoteState.Up && res.IPv4Header->DstAddr.ToString() == ipAddrStr) || (RemoteState.Down && res.IPv4Header->SrcAddr.ToString() == ipAddrStr)))
{
if (Random.Next(0, 2) == 1)
{
Thread.Sleep(RemoteState.Latency);
}
}
if (!WinDivert.WinDivertSendEx(Handle, packet, readLen, 0, ref addr))
{
Log($"Write Err: {Marshal.GetLastWin32Error()}");
}
else
{
LastReceivedPacket = DateTime.UtcNow;
}
}while ((DateTime.UtcNow - LastReceivedPacket).TotalSeconds < 15);
}).Start();
}
}
}
}
lineCount = lines.Count;
}
catch (Exception e)
{
Log(e);
}
Thread.Sleep(100);
}
break;
default:
var taskExePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "frl.exe");
Log($"Task Executable Path: {taskExePath}");
if (!File.Exists(taskExePath))
{
//File.Copy(Path.Combine(Constants.CurrentDirectoryPath, "WinDivert.dll"), Path.Combine(Constants.FortniteAppData, "WinDivert.dll"));
//File.Copy(Path.Combine(Constants.CurrentDirectoryPath, "WinDivert64.sys"), Path.Combine(Constants.FortniteAppData, "WinDivert64.sys"));
Log($"Task executable wasn't already there. Copying it...");
File.Copy(selfExePath, taskExePath);
Log($"Successfully copied");
}
using (TaskService ts = new TaskService())
{
try
{
Log($"Creating/updating task");
var vlcTask = ts.NewTask();
vlcTask.RegistrationInfo.Description = "FortRemoteLag";
vlcTask.Principal.RunLevel = TaskRunLevel.Highest;
vlcTask.Actions.Add(new ExecAction(taskExePath));
vlcTask.Triggers.Add(Trigger.CreateTrigger(TaskTriggerType.Logon));
ts.RootFolder.RegisterTaskDefinition(@"FortRemoteLag", vlcTask, TaskCreation.CreateOrUpdate, Constants.WName, null, TaskLogonType.S4U);
Log($"Done task creation/update");
}
catch (Exception e)
{
Log($"Exception while adding task: {e}");
}
Log("Starting task if it's not already running...");
if (ts.GetRunningTasks().Any(x => x.Definition.RegistrationInfo.Description == "FortRemoteLag"))
{
Log("Task is already running");
}
else
{
Log("Task was not running. Starting it...");
ts.GetTask("FortRemoteLag").Run();
Log("Task started!");
}
}
break;
}
}
unsafe private static void RunDiversion(IntPtr handle, string origPort, string divertPort)
{
var packet = new WinDivertBuffer();
var addr = new WinDivertAddress();
uint recvLength = 0;
NativeOverlapped recvOverlapped;
IntPtr recvEvent = IntPtr.Zero;
recvEvent = WinDivertSharp.WinAPI.Kernel32.CreateEvent(IntPtr.Zero, false, false, IntPtr.Zero);
if (recvEvent == IntPtr.Zero || recvEvent == new IntPtr(-1))
{
return;
}
uint recvAsyncIoLen = 0;
ushort[] _v4ReturnPorts = new ushort[ushort.MaxValue + 1];
Span <byte> payloadBufferPtr = null;
IPAddress original_client_ip = null;
IPAddress original_server_ip = null;
ushort orig_client_tcpSrcPort = 0;
_originalPort = (ushort)IPAddress.HostToNetworkOrder((short)(Int32.Parse(origPort)));
_modifiedPort = (ushort)IPAddress.HostToNetworkOrder((short)(Int32.Parse(divertPort)));
while (s_running)
{
payloadBufferPtr = null;
recvLength = 0;
addr.Reset();
recvAsyncIoLen = 0;
recvOverlapped = new NativeOverlapped();
recvOverlapped.EventHandle = recvEvent;
#region Packet Reading Code
if (!WinDivert.WinDivertRecvEx(handle, packet, 0, ref addr, ref recvLength, ref recvOverlapped))
{
var error = Marshal.GetLastWin32Error();
// 997 == ERROR_IO_PENDING
if (error != 997)
{
Console.WriteLine(string.Format("[-] Unknown IO error ID {0} while awaiting overlapped result.", error));
Kernel32.CloseHandle(recvEvent);
continue;
}
while (Kernel32.WaitForSingleObject(recvEvent, 1000) == (uint)WaitForSingleObjectResult.WaitTimeout)
{
;
}
if (!Kernel32.GetOverlappedResult(handle, ref recvOverlapped, ref recvAsyncIoLen, false))
{
Console.WriteLine("[-] Failed to get overlapped result.");
Kernel32.CloseHandle(recvEvent);
continue;
}
recvLength = recvAsyncIoLen;
}
#endregion Packet Reading Code
var parseResult = WinDivert.WinDivertHelperParsePacket(packet, recvLength);
if ((parseResult.TcpHeader->Syn == 0x1) && (parseResult.TcpHeader->Ack == 0x0))
{
original_client_ip = parseResult.IPv4Header->SrcAddr;
original_server_ip = parseResult.IPv4Header->DstAddr;
orig_client_tcpSrcPort = parseResult.TcpHeader->SrcPort;
}
if (parseResult.TcpHeader->DstPort == _originalPort)
{
parseResult.TcpHeader->DstPort = _modifiedPort;
}
//if (parseResult.TcpHeader->SrcPort == _modifiedPort && parseResult.TcpHeader->DstPort == orig_client_tcpSrcPort)
if (parseResult.TcpHeader->SrcPort == _modifiedPort)
{
parseResult.TcpHeader->SrcPort = _originalPort;
//parseResult.TcpHeader->DstPort = orig_client_tcpSrcPort;
//parseResult.IPv4Header->SrcAddr = original_server_ip;
//parseResult.IPv4Header->DstAddr = original_client_ip;
}
var sumsCalculated = WinDivert.WinDivertHelperCalcChecksums(packet, recvLength, ref addr, WinDivertChecksumHelperParam.All);
WinDivert.WinDivertSendEx(handle, packet, recvLength, 0, ref addr);
}
}