private static WinDivertAddress GetAddress(ReadOnlySpan <byte> p) { var version = p[0] >> 4; ReadOnlySpan <byte> srcBytes; ReadOnlySpan <byte> dstytes; if (version == 4) { srcBytes = p.Slice(IPv4Fields.SourcePosition, IPv4Fields.AddressLength); dstytes = p.Slice(IPv4Fields.DestinationPosition, IPv4Fields.AddressLength); } else { srcBytes = p.Slice(IPv6Fields.SourceAddressPosition, IPv6Fields.AddressLength); dstytes = p.Slice(IPv6Fields.DestinationAddressPosition, IPv6Fields.AddressLength); } var src = new IPAddress(srcBytes.ToArray()); var dst = new IPAddress(dstytes.ToArray()); WinDivertAddress addr = default; addr.IfIdx = (uint)IpHelper.GetBestInterfaceIndex(dst); if (IpHelper.IsOutbound((int)addr.IfIdx, src, dst)) { addr.Flags |= WinDivertPacketFlags.Outbound; } return(addr); }
/// <summary> /// </summary> /// <param name="p"></param> /// <param name="header"></param> public void SendPacket(ReadOnlySpan <byte> p, ICaptureHeader captureHeader) { ThrowIfNotOpen(); bool res; WinDivertAddress addr = default; if (!(captureHeader is WinDivertHeader)) { addr = GetAddress(p); } else { var header = captureHeader as WinDivertHeader; addr.IfIdx = header.InterfaceIndex; addr.SubIfIdx = header.SubInterfaceIndex; addr.Flags = header.Flags; } unsafe { fixed(byte *p_packet = p) { res = WinDivertNative.WinDivertSend(Handle, new IntPtr(p_packet), (uint)p.Length, out var pSendLen, ref addr); } } if (!res) { ThrowLastWin32Error("Can't send packet"); } }
public void SendPacket(RawCapture p) { if (p is WinDivertCapture packet) { WinDivertAddress address = default; address.IfIdx = packet.InterfaceIndex; address.SubIfIdx = packet.SubInterfaceIndex; address.Flags = packet.Flags; SendPacket(new ReadOnlySpan <byte>(p.Data), address); return; } SendPacket(new ReadOnlySpan <byte>(p.Data)); }
public PacketRecord(WinDivertAddress addr, ReadOnlyMemory <byte> data) { var timestamp = new PosixTimeval(BootTime + TimeSpan.FromTicks(addr.Timestamp)); Header = new WinDivertHeader(timestamp) { InterfaceIndex = addr.IfIdx, SubInterfaceIndex = addr.SubIfIdx, Flags = addr.Flags }; ; Data = data; }
public void SendPacket(Packet p, int size) { if (p is WinDivertPacket packet) { WinDivertAddress address = default; address.IfIdx = packet.InterfaceIndex; address.SubIfIdx = packet.SubInterfaceIndex; address.Flags = packet.Flags; SendPacket(new ReadOnlySpan <byte>(p.Bytes, 0, size), address); return; } SendPacket(new ReadOnlySpan <byte>(p.Bytes, 0, size)); }
private void SendPacket(ReadOnlySpan <byte> p, WinDivertAddress addr) { ThrowIfNotOpen(); bool res; unsafe { fixed(byte *p_packet = p) { res = WinDivertNative.WinDivertSend(Handle, new IntPtr(p_packet), (uint)p.Length, out var pSendLen, ref addr); } } if (!res) { ThrowLastWin32Error("Can't send packet"); } }
internal static extern bool WinDivertRecv(IntPtr handle, IntPtr pPacket, uint packetLen, out uint readLen, out WinDivertAddress pAddr);
/// <summary> /// Packet data is only valid until the next call /// </summary> /// <param name="packets"></param> /// <returns>Status of the operation</returns> private GetPacketStatus GetNextPackets(List <PacketRecord> packets, int maxBatchSize) { ThrowIfNotOpen(); while (true) { bool ret; var addressSize = Marshal.SizeOf <WinDivertAddress>(); var addressesByteSize = maxBatchSize * addressSize; var addresses = new WinDivertAddress[maxBatchSize]; var packetsData = new Memory <byte>(Buffer); ret = WinDivertNative.WinDivertRecvEx( Handle, ref MemoryMarshal.GetReference(packetsData.Span), packetsData.Length, out int readLen, 0, addresses, ref addressesByteSize, IntPtr.Zero ); if (!ret) { var err = Marshal.GetLastWin32Error(); if (err == ERROR_INSUFFICIENT_BUFFER) { // Increase buffer size Buffer = new byte[Buffer.Length * 2]; continue; } if (err == ERROR_NO_DATA) { return((GetPacketStatus)(-err)); } ThrowWin32Error("Recv failed", err); } // Take only as many bytes as were written by the driver packetsData = packetsData.Slice(0, readLen); var addressesCount = addressesByteSize / addressSize; for (int i = 0; i < addressesCount - 1; i++) { // We know how many packets we have, but not where they start/end in the buffer // Helper function that's originally used for parsing, // but we only need it to know the size of the current packet var retval = WinDivertNative.WinDivertHelperParsePacket( ref MemoryMarshal.GetReference(packetsData.Span), packetsData.Length, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, out var pNextLen ); if (!retval) { return(GetPacketStatus.Error); } var packetLength = packetsData.Length - pNextLen; packets.Add(new PacketRecord(addresses[i], packetsData.Slice(0, packetLength))); // Move packetsData to the next packet packetsData = packetsData.Slice(packetLength); } // Avoid parsing the packet if it's the last packet or the only packet packets.Add(new PacketRecord(addresses[addressesCount - 1], packetsData)); return(GetPacketStatus.PacketRead); } }
internal static extern bool WinDivertSend(IntPtr handle, IntPtr pPacket, uint packetLen, out uint pSendLen, ref WinDivertAddress pAddr);