Mega Code Archive
Returns true if the IPEndPoint supplied is on the same subnet as this host
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/* Copyright (c) 2010 Michael Lidgren
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom
the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Text;
using System.Text.RegularExpressions;
namespace Lidgren.Network
{
/// <summary>
/// Utility methods
/// </summary>
public static class NetUtility
{
/// <summary>
/// Returns true if the IPEndPoint supplied is on the same subnet as this host
/// </summary>
public static bool IsLocal(IPEndPoint endpoint)
{
if (endpoint == null)
return false;
return IsLocal(endpoint.Address);
}
/// <summary>
/// Returns true if the IPAddress supplied is on the same subnet as this host
/// </summary>
public static bool IsLocal(IPAddress remote)
{
IPAddress mask;
IPAddress local = GetMyAddress(out mask);
if (mask == null)
return false;
uint maskBits = BitConverter.ToUInt32(mask.GetAddressBytes(), 0);
uint remoteBits = BitConverter.ToUInt32(remote.GetAddressBytes(), 0);
uint localBits = BitConverter.ToUInt32(local.GetAddressBytes(), 0);
// compare network portions
return ((remoteBits & maskBits) == (localBits & maskBits));
}
/// <summary>
/// Gets my local IP address (not necessarily external) and subnet mask
/// </summary>
public static IPAddress GetMyAddress(out IPAddress mask)
{
NetworkInterface ni = GetNetworkInterface();
if (ni == null)
{
mask = null;
return null;
}
IPInterfaceProperties properties = ni.GetIPProperties();
foreach (UnicastIPAddressInformation unicastAddress in properties.UnicastAddresses)
{
if (unicastAddress != null && unicastAddress.Address != null && unicastAddress.Address.AddressFamily == AddressFamily.InterNetwork)
{
mask = unicastAddress.IPv4Mask;
return unicastAddress.Address;
}
}
mask = null;
return null;
}
private static NetworkInterface GetNetworkInterface()
{
IPGlobalProperties computerProperties = IPGlobalProperties.GetIPGlobalProperties();
if (computerProperties == null)
return null;
NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();
if (nics == null || nics.Length < 1)
return null;
NetworkInterface best = null;
foreach (NetworkInterface adapter in nics)
{
if (adapter.NetworkInterfaceType == NetworkInterfaceType.Loopback || adapter.NetworkInterfaceType == NetworkInterfaceType.Unknown)
continue;
if (!adapter.Supports(NetworkInterfaceComponent.IPv4))
continue;
if (best == null)
best = adapter;
if (adapter.OperationalStatus != OperationalStatus.Up)
continue;
// A computer could have several adapters (more than one network card)
// here but just return the first one for now...
return adapter;
}
return best;
}
}
}
]]>