jellyfin/Emby.Common.Implementations/Net/SocketFactory.cs
2016-11-04 04:31:05 -04:00

114 lines
5.9 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Threading.Tasks;
using MediaBrowser.Model.Net;
namespace Emby.Common.Implementations.Net
{
public class SocketFactory : ISocketFactory
{
// THIS IS A LINKED FILE - SHARED AMONGST MULTIPLE PLATFORMS
// Be careful to check any changes compile and work for all platform projects it is shared in.
// Not entirely happy with this. Would have liked to have done something more generic/reusable,
// but that wasn't really the point so kept to YAGNI principal for now, even if the
// interfaces are a bit ugly, specific and make assumptions.
/// <summary>
/// Used by RSSDP components to create implementations of the <see cref="IUdpSocket"/> interface, to perform platform agnostic socket communications.
/// </summary>
private IPAddress _LocalIP;
/// <summary>
/// Default constructor.
/// </summary>
/// <param name="localIP">A string containing the IP address of the local network adapter to bind sockets to. Null or empty string will use <see cref="IPAddress.Any"/>.</param>
public SocketFactory(string localIP)
{
if (String.IsNullOrEmpty(localIP))
_LocalIP = IPAddress.Any;
else
_LocalIP = IPAddress.Parse(localIP);
}
#region ISocketFactory Members
/// <summary>
/// Creates a new UDP socket that is a member of the SSDP multicast local admin group and binds it to the specified local port.
/// </summary>
/// <param name="localPort">An integer specifying the local port to bind the socket to.</param>
/// <returns>An implementation of the <see cref="IUdpSocket"/> interface used by RSSDP components to perform socket operations.</returns>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Justification = "The purpose of this method is to create and returns a disposable result, it is up to the caller to dispose it when they are done with it.")]
public IUdpSocket CreateUdpSocket(int localPort)
{
if (localPort < 0) throw new ArgumentException("localPort cannot be less than zero.", "localPort");
var retVal = new Socket(System.Net.Sockets.AddressFamily.InterNetwork, System.Net.Sockets.SocketType.Dgram, System.Net.Sockets.ProtocolType.Udp);
try
{
retVal.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
retVal.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.MulticastTimeToLive, 4);
retVal.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(IPAddress.Parse("239.255.255.250"), _LocalIP));
return new UdpSocket(retVal, localPort, _LocalIP.ToString());
}
catch
{
if (retVal != null)
retVal.Dispose();
throw;
}
}
/// <summary>
/// Creates a new UDP socket that is a member of the specified multicast IP address, and binds it to the specified local port.
/// </summary>
/// <param name="ipAddress">The multicast IP address to make the socket a member of.</param>
/// <param name="multicastTimeToLive">The multicast time to live value for the socket.</param>
/// <param name="localPort">The number of the local port to bind to.</param>
/// <returns></returns>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "ip"), System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Justification = "The purpose of this method is to create and returns a disposable result, it is up to the caller to dispose it when they are done with it.")]
public IUdpSocket CreateUdpMulticastSocket(string ipAddress, int multicastTimeToLive, int localPort)
{
if (ipAddress == null) throw new ArgumentNullException("ipAddress");
if (ipAddress.Length == 0) throw new ArgumentException("ipAddress cannot be an empty string.", "ipAddress");
if (multicastTimeToLive <= 0) throw new ArgumentException("multicastTimeToLive cannot be zero or less.", "multicastTimeToLive");
if (localPort < 0) throw new ArgumentException("localPort cannot be less than zero.", "localPort");
var retVal = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
try
{
#if NETSTANDARD1_3
// The ExclusiveAddressUse socket option is a Windows-specific option that, when set to "true," tells Windows not to allow another socket to use the same local address as this socket
// See https://github.com/dotnet/corefx/pull/11509 for more details
if (System.Runtime.InteropServices.RuntimeInformation.IsOSPlatform(System.Runtime.InteropServices.OSPlatform.Windows))
{
retVal.ExclusiveAddressUse = false;
}
#else
retVal.ExclusiveAddressUse = false;
#endif
retVal.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
retVal.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.MulticastTimeToLive, multicastTimeToLive);
retVal.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(IPAddress.Parse(ipAddress), _LocalIP));
retVal.MulticastLoopback = true;
return new UdpSocket(retVal, localPort, _LocalIP.ToString());
}
catch
{
if (retVal != null)
retVal.Dispose();
throw;
}
}
#endregion
}
}