/// <summary>
/// Gets the first <see cref="System.Net.NetworkInformation.NetworkInterface"/> which has the given address bound.
/// </summary>
/// <param name="localAddress">The address which should be bound to the interface.</param>
/// <returns>The <see cref="System.Net.NetworkInformation.NetworkInterface"/> associated with the address or the default if none were found.</returns>
public static System.Net.NetworkInformation.NetworkInterface GetNetworkInterface(System.Net.IPAddress localAddress)
{
if (localAddress == null)
{
throw new System.ArgumentNullException();
}
bool isMulticast = IPAddressExtensions.IsMulticast(localAddress);
//Iterate all NetworkInterfaves
foreach (System.Net.NetworkInformation.NetworkInterface networkInterface in System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces())
{
//Only look for interfaces which are UP
if (networkInterface.OperationalStatus != System.Net.NetworkInformation.OperationalStatus.Up)
{
continue;
}
if (isMulticast)
{
if (false == networkInterface.SupportsMulticast)
{
continue;
}
//Check for the Multicast Address to be bound on the networkInterface
foreach (System.Net.NetworkInformation.MulticastIPAddressInformation ip in networkInterface.GetIPProperties().MulticastAddresses)
{
//If equal return
if (System.Net.IPAddress.Equals(localAddress, ip.Address))
{
return(networkInterface);
}
}
}
else
{
//Check for the Unicast Address to be bound on the networkInterface
foreach (System.Net.NetworkInformation.UnicastIPAddressInformation ip in networkInterface.GetIPProperties().UnicastAddresses)
{
//If equal return
if (System.Net.IPAddress.Equals(localAddress, ip.Address))
{
return(networkInterface);
}
}
//Check for the Anycast Address to be bound on the networkInterface
//if(s.AddressFamily == System.Net.Sockets.AddressFamily.InterNetworkV6) foreach (System.Net.NetworkInformation.UnicastIPAddressInformation ip in networkInterface.GetIPProperties().AnycastAddresses)
//{
// if (System.Net.IPAddress.Equals(localEndPoint.Address, ip.Address))
// {
// return networkInterface;
// }
//}
}
}
return(default(System.Net.NetworkInformation.NetworkInterface));
}
public static bool IsMulticast(this System.Net.IPAddress ipAddress)
{
if (ipAddress == null)
{
return(false);
}
byte[] addressBytes;
switch (ipAddress.AddressFamily)
{
case System.Net.Sockets.AddressFamily.InterNetwork:
{
#if UNSAFE
unsafe
{
//Read bits as a byte
byte prop = (byte)(long *)ipAddress.Address;
//Return the result of the evaluation
return(prop >= 224 && prop <= 239);
}
#elif NATIVE
byte highIP = System.Runtime.InteropServices.Marshal.ReadByte(ipAddress.Address, 0);
return(highIP >= 224 && highIP <= 239);
#else
byte highIP = (byte)(ipAddress.Address & byte.MaxValue); // ipAddress.GetAddressBytes()[0];
return(highIP >= 224 && highIP <= 239);
#endif
}
case System.Net.Sockets.AddressFamily.InterNetworkV6:
{
//Check for a ipv6 multicast address
if (ipAddress.IsIPv6Multicast)
{
return(true);
}
//could use out overload and check in place or pass out to MapToIpv4...
//Check if mapped to v6 from v4 and unmap
if (IPAddressExtensions.IsIPv4MappedToIPv6(ipAddress, out addressBytes)) //(ipAddress.IsIPv4MappedToIPv6)
{
ipAddress = IPAddressExtensions.MapToIPv4(addressBytes); //ipAddress.MapToIPv4();
//handle as v4
goto case System.Net.Sockets.AddressFamily.InterNetwork;
}
return(false);
}
default: return(false);
}
}