/// <summary>绑定</summary>
/// <param name="request"></param>
/// <param name="session"></param>
/// <returns></returns>
protected void OnBind(StunMessage request, ISocketSession session)
{
var rs = new StunMessage
{
Type = StunMessageType.BindingResponse,
TransactionID = request.TransactionID.ReadBytes(),
MappedAddress = session.Remote.EndPoint
};
//rs.SourceAddress = session.GetRelativeEndPoint(remote.Address);
if (Public != null)
{
if (session.Local.IsTcp)
{
rs.SourceAddress = Public[session.Port + 100000];
}
else
{
rs.SourceAddress = Public[session.Port];
}
}
// 找另一个
ISocketSession session2 = null;
var anotherPort = 0;
for (var i = 0; i < Servers.Count; i++)
{
var server = Servers[i];
if (server.Local.Type == session.Local.Type && server.Local.Port != session.Local.Port)
{
anotherPort = server.Port;
if (server.Local.IsTcp)
{
break;
}
else
{
session2 = (server as UdpServer).CreateSession(session.Remote.EndPoint);
if (session2 != null)
{
break;
}
}
}
}
//rs.ChangedAddress = Partner ?? session2.GetRelativeEndPoint(remote.Address);
if (Public != null)
{
if (session.Local.IsTcp)
{
rs.ChangedAddress = Partner ?? Public[anotherPort + 100000];
}
else
{
rs.ChangedAddress = Partner ?? Public[anotherPort];
}
}
var name = Name;
if (name == GetType().Name)
{
name = GetType().FullName;
}
rs.ServerName = String.Format("{0} v{1}", name, AssemblyX.Create(Assembly.GetExecutingAssembly()).CompileVersion);
// 换成另一个
if (request.ChangePort)
{
session = session2;
}
session.Send(rs.ToArray());
}
/// <summary>查询</summary>
/// <param name="request"></param>
/// <param name="remoteEndPoint"></param>
/// <returns></returns>
public StunMessage Query(StunMessage request, IPEndPoint remoteEndPoint)
{
EnsureSocket();
return(Query(Socket, request, remoteEndPoint));
}
/// <summary>接收到数据时</summary>
/// <param name="session"></param>
/// <param name="pk"></param>
protected override void OnReceive(INetSession session, Packet pk)
{
if (pk.Total > 0)
{
var remote = session.Remote;
//if (remote == null && session != null) remote = session.RemoteEndPoint;
var request = StunMessage.Read(pk.GetStream());
WriteLog("{0} {1} {2}{3}", request.Type, remote, request.ChangeIP ? " ChangeIP" : "", request.ChangePort ? " ChangePort" : "");
// 如果是兄弟服务器发过来的，修正响应地址
switch (request.Type)
{
case StunMessageType.BindingRequest:
//case StunMessageType.BindingResponse:
request.Type = StunMessageType.BindingRequest;
if (request.ResponseAddress != null)
{
remote.EndPoint = request.ResponseAddress;
}
break;
case StunMessageType.SharedSecretRequest:
//case StunMessageType.SharedSecretResponse:
request.Type = StunMessageType.SharedSecretRequest;
if (request.ResponseAddress != null)
{
remote.EndPoint = request.ResponseAddress;
}
break;
default:
break;
}
// 是否需要发给伙伴
if (request.ChangeIP)
{
//if (Partner != null && !Partner.Equals(session.Host.LocalEndPoint.GetRelativeEndPoint(Partner.Address)))
//{
// // 发给伙伴
// request.ChangeIP = false;
// // 记住对方的地址
// request.ResponseAddress = remote.EndPoint;
// //session.Send(request.GetStream(), Partner);
// var us = session.Host as UdpServer;
// if (us != null)
// {
// //us.CreateSession(Partner).Send(request.GetStream());
// us.Send(request.GetStream(), Partner);
// }
// return;
//}
// 如果没有伙伴地址，采用不同端口代替
request.ChangePort = true;
}
// 开始分流处理
switch (request.Type)
{
case StunMessageType.BindingRequest:
//case StunMessageType.BindingResponse:
OnBind(request, session.Session);
break;
case StunMessageType.SharedSecretRequest:
break;
default:
break;
}
}
}
///// <summary>在指定服务器上执行查询</summary>
///// <param name="host"></param>
///// <param name="port"></param>
///// <returns></returns>
//public StunResult QueryWithServer(String host, Int32 port = 3478)
//{
// try
// {
// return QueryWithServer(NetHelper.ParseAddress(host), port);
// }
// catch { return null; }
//}
/// <summary>在指定服务器上执行查询</summary>
/// <param name="address"></param>
/// <param name="port"></param>
/// <returns></returns>
public StunResult QueryWithServer(IPAddress address, Int32 port)
{
EnsureSocket();
var client = Socket as ISocketClient;
var remote = new IPEndPoint(address, port);
// Test I
// 测试网络是否畅通
var msg = new StunMessage();
msg.Type = StunMessageType.BindingRequest;
var rs = Query(client, msg, remote);
// UDP blocked.
if (rs == null)
{
return(new StunResult(StunNetType.Blocked, null));
}
WriteLog("服务器：{0}", rs.ServerName);
WriteLog("映射地址：{0}", rs.MappedAddress);
WriteLog("源地址：{0}", rs.SourceAddress);
WriteLog("新地址：{0}", rs.ChangedAddress);
var remote2 = rs.ChangedAddress;
// Test II
// 要求改变IP和端口
msg.ChangeIP = true;
msg.ChangePort = true;
msg.ResetTransactionID();
// 如果本地地址就是映射地址，表示没有NAT。这里的本地地址应该有问题，永远都会是0.0.0.0
//if (client.LocalEndPoint.Equals(test1response.MappedAddress))
var pub = rs.MappedAddress;
if (pub != null && client.Local.Port == pub.Port && pub.Address.IsLocal())
{
// 要求STUN服务器从另一个地址和端口向当前映射端口发送消息。如果收到，表明是完全开放网络；如果没收到，可能是防火墙阻止了。
rs = Query(client, msg, remote);
// Open Internet.
if (rs != null)
{
return(new StunResult(StunNetType.OpenInternet, pub));
}
// Symmetric UDP firewall.
return(new StunResult(StunNetType.SymmetricUdpFirewall, pub));
}
else
{
rs = Query(client, msg, remote);
if (rs != null && pub == null)
{
pub = rs.MappedAddress;
}
// Full cone NAT.
if (rs != null)
{
return(new StunResult(StunNetType.FullCone, pub));
}
// Test II
msg.ChangeIP = false;
msg.ChangePort = false;
msg.ResetTransactionID();
// 如果是Tcp，这里需要准备第二个重用的Socket
if (client.Local.IsTcp)
{
EnsureSocket2();
client = Socket2 as ISocketClient;
}
rs = Query(client, msg, remote2);
// 如果第二服务器没响应，重试
if (rs == null)
{
rs = Query(client, msg, remote2);
}
if (rs != null && pub == null)
{
pub = rs.MappedAddress;
}
if (rs == null)
{
return(new StunResult(StunNetType.Blocked, pub));
}
// 两次映射地址不一样，对称网络
if (!rs.MappedAddress.Equals(pub))
{
return(new StunResult(StunNetType.Symmetric, pub));
}
// Test III
msg.ChangeIP = false;
msg.ChangePort = true;
msg.ResetTransactionID();
rs = Query(client, msg, remote2);
if (rs != null && pub == null)
{
pub = rs.MappedAddress;
}
// 受限
if (rs != null)
{
return(new StunResult(StunNetType.AddressRestrictedCone, pub));
}
// 端口受限
return(new StunResult(StunNetType.PortRestrictedCone, pub));
}
}
