private static unsafe int EstimateBufferSize(AddressFamily addressFamily, TCP_TABLE_CLASS tableClass)
{
var size = 0;
var status = IPHlpApi.GetExtendedTcpTable(null, ref size, false, addressFamily, tableClass, 0);
if (status != (int)ErrorCodes.ERROR_INSUFFICIENT_BUFFER)
{
Win32ExceptionUtility.Throw(status);
}
return(size);
}
private unsafe HashSet <string> BuildCache()
{
var size = 1024;
lock (sync)
{
while (true)
{
var buffer = resizeableBuffer.Get(ref size, false);
fixed(byte *b = buffer)
{
var result = IPHlpApi.GetAdaptersAddresses(
AddressFamily.AF_UNSPEC,
GetAdaptersAddressesFlags.GAA_FLAG_INCLUDE_WINS_INFO |
GetAdaptersAddressesFlags.GAA_FLAG_INCLUDE_GATEWAYS |
GetAdaptersAddressesFlags.GAA_FLAG_INCLUDE_ALL_INTERFACES,
IntPtr.Zero,
b,
ref size);
if (result == (int)ErrorCodes.ERROR_BUFFER_OVERFLOW)
{
continue;
}
if (result == (int)ErrorCodes.ERROR_NO_DATA)
{
return(new HashSet <string>(StringComparer.OrdinalIgnoreCase));
}
if (result != (int)ErrorCodes.ERROR_SUCCESS)
{
Win32ExceptionUtility.Throw(result);
}
var upInterfaces = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
for (var ptr = (IP_ADAPTER_ADDRESSES *)b; ptr != null; ptr = ptr->Next)
{
UnsafeHelper.CheckBounds(b, size, ptr, sizeof(IP_ADAPTER_ADDRESSES));
if (ptr->OperStatus == OperationalStatus.Up && ptr->IfType != NetworkInterfaceType.Loopback)
{
upInterfaces.Add(GetAdapterIdentity(new string(ptr->Description)));
}
}
return(upInterfaces);
}
}
}
}
private static unsafe void GetTcpTableWithPid(AddressFamily addressFamily, ResizeableBuffer resizeableBuffer)
{
var size = EstimateBufferSize(addressFamily, TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL);
var buffer = resizeableBuffer.Get(ref size);
while (true)
{
fixed(byte *b = buffer)
{
var result = IPHlpApi.GetExtendedTcpTable(b, ref size, false, addressFamily,
TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL, 0);
if (result == (int)ErrorCodes.ERROR_INSUFFICIENT_BUFFER)
{
buffer = resizeableBuffer.Get(ref size);
continue;
}
if (result != 0)
{
Win32ExceptionUtility.Throw(result);
}
var itemSize = addressFamily == AddressFamily.AF_INET
? sizeof(MIB_TCPROW_OWNER_PID)
: sizeof(MIB_TCP6ROW_OWNER_PID);
var itemCount = *(int *)b;
if (itemCount * itemSize + 4 > buffer.Length)
{
throw new InvalidOperationException($"Buffer overflow check failed. ItemCount: {itemCount}, ItemSize: {itemSize}, BufferSize: {buffer.Length}");
}
return;
}
}
}
public unsafe void GetExtendedTcpTableTest()
{
IntPtr tcpTablePtr = IntPtr.Zero;
int tcpTableLength = 0;
if (IPHlpApi.GetExtendedTcpTable(tcpTablePtr, ref tcpTableLength, bOrder: true, AddressFamily.InterNetwork, IPHlpApi.TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL, 0) == Win32ErrorCode.ERROR_INSUFFICIENT_BUFFER)
{
try
{
tcpTablePtr = Marshal.AllocHGlobal(tcpTableLength);
if (IPHlpApi.GetExtendedTcpTable(tcpTablePtr, ref tcpTableLength, bOrder: true, AddressFamily.InterNetwork, IPHlpApi.TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL, 0) == Win32ErrorCode.ERROR_SUCCESS)
{
IPHlpApi.MIB_TCPTABLE_OWNER_PID *tcpTable = (IPHlpApi.MIB_TCPTABLE_OWNER_PID *)tcpTablePtr;
var tableSize = sizeof(IPHlpApi.MIB_TCPTABLE_OWNER_PID);
IPHlpApi.MIB_TCPROW_OWNER_PID *tcpRow = (IPHlpApi.MIB_TCPROW_OWNER_PID *)(tcpTablePtr + tableSize);
for (int i = 0; i < tcpTable->dwNumEntries; ++i)
{
Assert.InRange(tcpRow->LocalPort, 0, 65535);
Assert.True(Enum.IsDefined(typeof(TcpState), tcpRow->dwState));
tcpRow++;
}
}
}
finally
{
if (tcpTablePtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(tcpTablePtr);
}
}
}
}